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Sample records for surrounding epidermal cells

  1. Surface position, not signaling from surrounding maternal tissues, specifies aleurone epidermal cell fate in maize.

    Science.gov (United States)

    Gruis, Darren Fred; Guo, Hena; Selinger, David; Tian, Qing; Olsen, Odd-Arne

    2006-07-01

    Maize (Zea mays) endosperm consists of an epidermal-like surface layer of aleurone cells, an underlying body of starchy endosperm cells, and a basal layer of transfer cells. To determine whether surrounding maternal tissues perform a role in specifying endosperm cell fates, a maize endosperm organ culture technique was established whereby the developing endosperm is completely removed from surrounding maternal tissues. Using cell type-specific fluorescence markers, we show that aleurone cell fate specification occurs exclusively in response to surface position and does not require specific, continued maternal signal input. The starchy endosperm and aleurone cell fates are freely interchangeable throughout the lifespan of the endosperm, with internalized aleurone cells converting to starchy endosperm cells and with starchy endosperm cells that become positioned at the surface converting to aleurone cells. In contrast to aleurone and starchy endosperm cells, transfer cells fail to develop in in vitro-grown endosperm, supporting earlier indications that maternal tissue interaction is required to fully differentiate this cell type. Several parameters confirm that the maize endosperm organ cultures described herein retain the main developmental features of in planta endosperm, including fidelity of aleurone mutant phenotypes, temporal and spatial control of cell type-specific fluorescent markers, specificity of cell type transcripts, and control of mitotic cell divisions.

  2. Niche interactions in epidermal stem cells

    Institute of Scientific and Technical Information of China (English)

    Hye-Ryung Choi; Sang-Young Byun; Soon-Hyo Kwon; Kyoung-Chan Park

    2015-01-01

    Within the epidermis and dermis of the skin, cellssecrete and are surrounded by the extracellular matrix(ECM), which provides structural and biochemicalsupport. The ECM of the epidermis is the basementmembrane, and collagen and other dermal componentsconstitute the ECM of the dermis. There is significantvariation in the composition of the ECM of the epidermisand dermis, which can affect "cell to cell" and "cellto ECM" interactions. These interactions, in turn, caninfluence biological responses, aging, and woundhealing; abnormal ECM signaling likely contributes toskin diseases. Thus, strategies for manipulating cell-ECM interactions are critical for treating wounds and avariety of skin diseases. Many of these strategies focuson epidermal stem cells, which reside in a unique nichein which the ECM is the most important component;interactions between the ECM and epidermal stemcells play a major role in regulating stem cell fate. Asthey constitute a major portion of the ECM, it is likelythat integrins and type Ⅳ collagens are important instem cell regulation and maintenance. In this review,we highlight recent research-including our previouswork-exploring the role that the ECM and its associatedcomponents play in shaping the epidermal stem cellniche.

  3. Targeting epidermal Langerhans cells by epidermal powder immunization

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Immune reactions to foreign or self-antigens lead to protective immunity and, sometimes, immune disorders such as allergies and autoimmune diseases. Antigen presenting cells (APC) including epidermal Langerhans cells (LCs) play an important role in the course and outcome of the immune reactions. Epidermal powder immunization (EPI) is a technology that offers a tool to manipulate the LCs and the potential to harness the immune reactions towards prevention and treatment of infectious diseases and immune disorders.

  4. Mechanotransduction in epidermal Merkel cells.

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    Nakatani, Masashi; Maksimovic, Srdjan; Baba, Yoshichika; Lumpkin, Ellen A

    2015-01-01

    The cellular and molecular basis of vertebrate touch reception remains least understood among the traditional five senses. Somatosensory afferents that innervate the skin encode distinct tactile qualities, such as flutter, slip, and pressure. Gentle touch is thought to be transduced by somatosensory afferents whose tactile end organs selectively filter mechanical stimuli. These tactile end organs comprise afferent terminals in association with non-neuronal cell types such as Merkel cells, keratinocytes, and Schwann cells. An open question is whether these non-neuronal cells serve primarily as passive mechanical filters or whether they actively participate in mechanosensory transduction. This question has been most extensively studied in Merkel cells, which are epidermal cells that complex with sensory afferents in regions of high tactile acuity such as fingertips, whisker follicles, and touch domes. Merkel cell-neurite complexes mediate slowly adapting type I (SAI) responses, which encode sustained pressure and represent object features with high fidelity. How Merkel cells contribute to unique SAI firing patterns has been debated for decades; however, three recent studies in rodent models provide some direct answers. First, whole-cell recordings demonstrate that Merkel cells are touch-sensitive cells with fast, mechanically activated currents that require Piezo2. Second, optogenetics and intact recordings show that Merkel cells mediate sustained SAI firing. Finally, loss-of-function studies in transgenic mouse models reveal that SAI afferents are also touch sensitive. Together, these studies identify molecular mechanisms of mechanotransduction in Merkel cells, reveal unexpected functions for these cells in touch, and support a revised, two-receptor site model of mechanosensory transduction.

  5. Epidermal cell death in frogs with chytridiomycosis

    Science.gov (United States)

    Roberts, Alexandra A.; Skerratt, Lee F.; Berger, Lee

    2017-01-01

    Background Amphibians are declining at an alarming rate, and one of the major causes of decline is the infectious disease chytridiomycosis. Parasitic fungal sporangia occur within epidermal cells causing epidermal disruption, but these changes have not been well characterised. Apoptosis (planned cell death) can be a damaging response to the host but may alternatively be a mechanism of pathogen removal for some intracellular infections. Methods In this study we experimentally infected two endangered amphibian species Pseudophryne corroboree and Litoria verreauxii alpina with the causal agent of chytridiomycosis. We quantified cell death in the epidermis through two assays: terminal transferase-mediated dUTP nick end-labelling (TUNEL) and caspase 3/7. Results Cell death was positively associated with infection load and morbidity of clinically infected animals. In infected amphibians, TUNEL positive cells were concentrated in epidermal layers, correlating to the localisation of infection within the skin. Caspase activity was stable and low in early infection, where pathogen loads were light but increasing. In animals that recovered from infection, caspase activity gradually returned to normal as the infection cleared. Whereas, in amphibians that did not recover, caspase activity increased dramatically when infection loads peaked. Discussion Increased cell death may be a pathology of the fungal parasite, likely contributing to loss of skin homeostatic functions, but it is also possible that apoptosis suppression may be used initially by the pathogen to help establish infection. Further research should explore the specific mechanisms of cell death and more specifically apoptosis regulation during fungal infection. PMID:28168107

  6. Squamous cell carcinoma arising in a multiple verrucous epidermal nevus*

    Science.gov (United States)

    Yarak, Samira; Machado, Taila Yuri Siqueira; Ogawa, Marilia Marufuji; Almeida, Mirian Luzia da Silva; Enokihara, Milvia Maria Simões e Silva; Porro, Adriana Maria

    2016-01-01

    Verrucous epidermal nevi are hamartomatous lesions of the epidermis that, unlike other epidermal nevi (such as sebaceous nevus or nevus comedonicus), are rarely associated with malignant neoplasms. The majority of squamous cell carcinoma develop in linear or multiple epidermal nevus and rarely in solitary epidermal nevus. In general, the prognosis is favorable. We report a case of well-differentiated invasive squamous cell carcinoma arising from a multiple verrucous epidermal nevus. Although there is no consensus on prophylactic removal of epidermal nevus, its removal and biopsy should be considered if changes occur. PMID:28300931

  7. Epidermal cell density is autoregulated via a secretory peptide, EPIDERMAL PATTERNING FACTOR 2 in Arabidopsis leaves.

    Science.gov (United States)

    Hara, Kenta; Yokoo, Toshiya; Kajita, Ryoko; Onishi, Takaaki; Yahata, Saiko; Peterson, Kylee M; Torii, Keiko U; Kakimoto, Tatsuo

    2009-06-01

    Regulation of the number of cells is critical for development of multicellular organisms. During plant epidermal development, a protodermal cell first makes a fate decision of whether or not to be the meristemoid mother cell (MMC), which undergoes asymmetric cell division forming a meristemoid and its sister cell. The MMC-derived lineage produces all stomatal guard cells and a large proportion of non-guard cells. We demonstrate that a small secretory peptide, EPIDERMAL PATTERING FACTOR 2 (EPF2), is produced by the MMC and its early descendants, and negatively regulates the density of guard and non-guard epidermal cells. Our results suggest that EPF2 inhibits cells from adopting the MMC fate in a non-cell-autonomous manner, thus limiting the number of MMCs. This feedback loop is critical for regulation of epidermal cell density. The amino acid sequence of EPF2 resembles that of EPF1, which is known to control stomatal positioning. Over-expression of EPF1 also inhibits stomatal development, but EPF1 can act only on a later developmental process than EPF2. Overexpression and promoter swapping experiments suggested that the protein functions of EPF1 and EPF2, rather than the expression patterns of the genes, are responsible for the specific functions. Although targets of EPF1 and EPF2 are different, both EPF1 and EPF2 require common putative receptor components TOO MANY MOUTHS (TMM), ERECTA (ER), ERECTA LIKE 1 (ERL1) and ERL2 in order to function.

  8. Specification of Epidermal Cell Fate in Plant Shoots

    Directory of Open Access Journals (Sweden)

    Shinobu eTakada

    2014-02-01

    Full Text Available Land plants have evolved a single layer of epidermal cells, which are characterized by mostly anticlinal cell division patterns, formation of a waterproof coat called cuticle, and unique cell types such as stomatal guard cells and trichomes. The shoot epidermis plays important roles not only to protect plants from dehydration and pathogens but also to ensure their proper organogenesis and growth control. Extensive molecular genetic studies in Arabidopsis and maize have identified a number of genes that are required for epidermal cell differentiation. However, the mechanism that specifies shoot epidermal cell fate during plant organogenesis remains largely unknown. Particularly, little is known regarding positional information that should restrict epidermal cell fate to the outermost cell layer of the developing organs. Recent studies suggested that certain members of the HD-ZIP class IV homeobox genes are possible master regulators of shoot epidermal cell fate. Here, we summarize the roles of the regulatory genes that are involved in epidermal cell fate specification and discuss the possible mechanisms that limit the expression and/or activity of the master transcriptional regulators to the outermost cell layer in plant shoots.

  9. Autologous epidermal cell suspension: A promising treatment for chronic wounds.

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    Zhao, Hongliang; Chen, Yan; Zhang, Cuiping; Fu, Xiaobing

    2016-02-01

    Chronic wounds have become an increasing medical and economic problem of aging societies because they are difficult to manage. Skin grafting is an important treatment method for chronic wounds, which are refractory to conservative therapy. The technique involving epidermal cell suspensions was invented to enable the possibility of treating larger wounds with only a small piece of donor skin. Both uncultured and cultured autologous epidermal cell suspensions can be prepared and survive permanently on the wound bed. A systematic search was conducted of EMBASE, Cochrane Library, PubMed and web of science by using Boolean search terms, from the establishment of the database until May 31, 2014. The bibliographies of all retrieved articles in English were searched. The search terms were: (epithelial cell suspension OR keratinocyte suspension) and chronic and wound. From the included, 6 studies are descriptive interventions and discussed the use of autologous keratinocyte suspension to treat 61 patients' chronic wound. The various methods of preparation of epidermal cell suspension are described. The advantages and shortcomings of different carriers for epidermal cell suspensions are also summarised. Both uncultured and cultured autologous epidermal cell suspensions have been used to treat chronic wounds. Although the limitations of these studies include the small number of patient populations with chronic wounds and many important problems that remain to be solved, autologous epidermal cell suspension is a promising treatment for chronic wounds. Copyright © 2015 Tissue Viability Society. Published by Elsevier Ltd. All rights reserved.

  10. ATML1 promotes epidermal cell differentiation in Arabidopsis shoots.

    Science.gov (United States)

    Takada, Shinobu; Takada, Nozomi; Yoshida, Ayaka

    2013-05-01

    Molecular mechanisms that generate distinct tissue layers in plant shoots are not well understood. ATML1, an Arabidopsis homeobox gene, is expressed in the outermost cell layer, beginning at an early stage of development. The promoters of many epidermis-specific genes, including ATML1, contain an ATML1-binding site called an L1 box, suggesting that ATML1 regulates epidermal cell fate. Here, we show that overexpression of ATML1 was sufficient to activate the expression of epidermal genes and to induce epidermis-related traits such as the formation of stomatal guard cells and trichome-like cells in non-epidermal seedling tissues. Detailed observation of the division planes of these ectopic stomatal cells suggested that a near-surface position, as well as epidermal cell identity, were required for regular anticlinal cell division, as seen in wild-type epidermis. Moreover, analyses of a loss-of-function mutant and overexpressors implied that differentiation of epidermal cells was associated with repression of mesophyll cell fate. Collectively, our studies contribute new information about the molecular basis of cell fate determination in different layers of plant aerial organs.

  11. Epidermal cells are the primary phagocytes in the fragmentation and clearance of degenerating dendrites in Drosophila.

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    Han, Chun; Song, Yuanquan; Xiao, Hui; Wang, Denan; Franc, Nathalie C; Jan, Lily Yeh; Jan, Yuh-Nung

    2014-02-05

    During developmental remodeling, neurites destined for pruning often degenerate on-site. Physical injury also induces degeneration of neurites distal to the injury site. Prompt clearance of degenerating neurites is important for maintaining tissue homeostasis and preventing inflammatory responses. Here we show that in both dendrite pruning and dendrite injury of Drosophila sensory neurons, epidermal cells rather than hemocytes are the primary phagocytes in clearing degenerating dendrites. Epidermal cells act via Draper-mediated recognition to facilitate dendrite degeneration and to engulf and degrade degenerating dendrites. Using multiple dendritic membrane markers to trace phagocytosis, we show that two members of the CD36 family, croquemort (crq) and debris buster (dsb), act at distinct stages of phagosome maturation for dendrite clearance. Our finding reveals the physiological importance of coordination between neurons and their surrounding epidermis, for both dendrite fragmentation and clearance.

  12. The circadian molecular clock creates epidermal stem cell heterogeneity.

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    Janich, Peggy; Pascual, Gloria; Merlos-Suárez, Anna; Batlle, Eduard; Ripperger, Jürgen; Albrecht, Urs; Cheng, Hai-Ying M; Obrietan, Karl; Di Croce, Luciano; Benitah, Salvador Aznar

    2011-11-09

    Murine epidermal stem cells undergo alternate cycles of dormancy and activation, fuelling tissue renewal. However, only a subset of stem cells becomes active during each round of morphogenesis, indicating that stem cells coexist in heterogeneous responsive states. Using a circadian-clock reporter-mouse model, here we show that the dormant hair-follicle stem cell niche contains coexisting populations of cells at opposite phases of the clock, which are differentially predisposed to respond to homeostatic cues. The core clock protein Bmal1 modulates the expression of stem cell regulatory genes in an oscillatory manner, to create populations that are either predisposed, or less prone, to activation. Disrupting this clock equilibrium, through deletion of Bmal1 (also known as Arntl) or Per1/2, resulted in a progressive accumulation or depletion of dormant stem cells, respectively. Stem cell arrhythmia also led to premature epidermal ageing, and a reduction in the development of squamous tumours. Our results indicate that the circadian clock fine-tunes the temporal behaviour of epidermal stem cells, and that its perturbation affects homeostasis and the predisposition to tumorigenesis.

  13. Leaf Epidermal Cells: A Trap for Lipophilic Xenobiotics

    Institute of Scientific and Technical Information of China (English)

    Zhiqian Liu

    2006-01-01

    Plant surfaces are covered by a layer of cuticle, which functions as a natural barrier to protect plants from mechanical damage, desiccation, and microbial invasion. Results presented in this report show that the epicuticular wax and the cuticle of plant leaves also play an important role in resisting xenobiotic invasion.Although the epicuticular wax is impermeableto hydrophilic xenobiotics, the cuticle not only restricts the penetration of hydrophilic compounds into leaf cells, but also traps lipophilic ones. The role of the epidermal cells of plant leaves in resisting xenobiotic invasion has been neglected until now. The present study shows, for the first time, that the epidermal cells may reduce or retard the transport of lipophilic xenobiotics into the internal tissues through vacuolar sequestration. Although the guard cells appear to be an easy point of entry for xenobiotics, only a very small proportion of xenobiotics present on the leaf surface actually moves into leaf tissues via the guard cells.

  14. Epidermal growth factor induces changes of interaction between epidermal growth factor receptor and actin in intact cells

    Institute of Scientific and Technical Information of China (English)

    Wei Song; Haixing Xuan; Qishui Lin

    2008-01-01

    The epidermal growth factor receptor (EGFR) is a cyto-skeleton-binding protein. Although purified EGFR can interact with actins in vitro and normally at least 10% of EGFR exist in the insoluble cytoskeleton fraction of A431 cells, interaction of cytosolic EGFR with actin can only be visualized by fluorescence resonance energy transfer when epidermal growth factor presents in the cell medium. Results indicate that the correct orientation between EGFR and actin is important in the signal transduction process.

  15. Micromorphology and development of the epicuticular structure on the epidermal cell of ginseng leaves

    Directory of Open Access Journals (Sweden)

    Kyounghwan Lee

    2015-04-01

    Conclusion: The outwardly projected cuticle and epidermal cell wall (i.e., an epicuticular wrinkle acts as a major barrier to block out sunlight in ginseng leaves. The small vesicles in the peripheral region of epidermal cells may suppress the cuticle and parts of epidermal wall, push it upward, and consequently contribute to the formation of the epicuticular structure.

  16. Squamous cell carcinoma arising from an epidermal cyst in the thumb

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    Akio Sakamoto

    2015-01-01

    Discussion and conclusion: The clinical symptoms of squamous cell carcinoma arising from an epidermal cyst can mimic those of an infected epidermal cyst. The current report facilitates awareness of such disease.

  17. EGFR-ras-raf signaling in epidermal stem cells: roles in hair follicle development, regeneration, tissue remodeling and epidermal cancers.

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    Doma, Eszter; Rupp, Christian; Baccarini, Manuela

    2013-09-25

    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.

  18. Heterogeneity and plasticity of epidermal stem cells

    DEFF Research Database (Denmark)

    Schepeler, Troels; Page, Mahalia E; Jensen, Kim Bak

    2014-01-01

    facilitate this task. In this Review, we discuss stem cell behaviour during normal tissue homeostasis, regeneration and disease within the pilosebaceous unit, an integral structure of the epidermis that is responsible for hair growth and lubrication of the epithelium. We provide an up-to-date view...

  19. Kinetics of cell division in epidermal maintenance

    CERN Document Server

    Klein, Allon M; Jones, Philip H; Simons, Benjamin D

    2007-01-01

    The rules governing cell division and differentiation are central to understanding the mechanisms of development, aging and cancer. By utilising inducible genetic labelling, recent studies have shown that the clonal population in transgenic mouse epidermis can be tracked in vivo. Drawing on these results, we explain how clonal fate data may be used to infer the rules of cell division and differentiation underlying the maintenance of adult murine tail-skin. We show that the rates of cell division and differentiation may be evaluated by considering the long-time and short-time clone fate data, and that the data is consistent with cells dividing independently rather than synchronously. Motivated by these findings, we consider a mechanism for cancer onset based closely on the model for normal adult skin. By analysing the expected changes to clonal fate in cancer emerging from a simple two-stage mutation, we propose that clonal fate data may provide a novel method for studying the earliest stages of the disease.

  20. Squamous cell carcinoma arising from an epidermal cyst in the thumb

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    Sakamoto, Akio; Shiba, Eisuke; Hisaoka, Masanori

    2015-01-01

    Introduction Squamous cell carcinoma arising from an epidermal cyst is rare, and the most frequently affected region is the head and neck. Presentation of case A 41-year-old man noticed swelling and a small ulceration in the thumb pulp. A lesion with a 2-cm diameter was simply resected based on a diagnosis of infected epidermal cyst. Pathological diagnosis of the resected material was squamous cell carcinoma arising from an epidermal cyst. Consequent amputation was performed. Discussion and conclusion The clinical symptoms of squamous cell carcinoma arising from an epidermal cyst can mimic those of an infected epidermal cyst. The current report facilitates awareness of such disease. PMID:25912006

  1. Putative epidermal stem cell convert into corneal epithelium-like cell under corneal tissue in vitro

    Institute of Scientific and Technical Information of China (English)

    GAO Nan; CUI GuangHui; WANG ZhiChong; HUANG Bing; GE Jian; LU Rong; ZHANG KeFei; FAN ZhiGang; LU Li; PENG Zhan

    2007-01-01

    Rhesus putative epidermal stem cells are being investigated for their potential use in regenerative corneal epithelium-like cells, which may provide a practical source of autologous seed cells for the construction of bioengineered corneas. The goal of this study was to investigate the potential of epidermal stem cells for trans-differentiation into corneal epithelium-like cells. Rhesus putative epidermal stem cells were isolated by type IV collagen attachment method. Flow cytometry analysis, immunohistology and RT-PCR were conducted to identify the expression of specific markers (β1, α6 integrin, K15, K1/K10, K3/K12 and CD71) on the isolated rapid attaching cells. The isolated cells were cocultured with human corneal limbal stroma and corneal epithelial cells. After coculture, the expression of the same specific markers was evaluated in order to identify expression difference caused by the coculture conditions. K3/K12 expression was analyzed in coculture cells on day 2, 4, 6, 8 and 10. Putative epidermal stem cells in conditioned culture media were used as control. Putative epidermal stem cells were predominant in rapid attaching cells by type IV collagen attachment isolation. Before being cocultured, the rhesus putative epidermal stem cells expressed K15, α6 and β1 integrin, but no CD71, K1/K10 and K3/K12. After coculture, these cells expressed K3/K12 (a marker of corneal epithelial cells), K15 and β 1 integrin, but no K1/K10. Cells being not coculture converted into terminally differentiated cells expressing K1/K10. These results indicate that rhesus putative epidermal stem cells can trans-differentiate into corneal epithelium-like cells and, therefore, may have potential therapeutic application as autologous seed cells for the construction of bioengineered corneas.

  2. Putative epidermal stem cell convert into corneal epithelium-like cell under corneal tissue in vitro

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Rhesus putative epidermal stem cells are being investigated for their potential use in regenerative corneal epithelium-like cells, which may provide a practical source of autologous seed cells for the construction of bioengineered corneas. The goal of this study was to investigate the potential of epi-dermal stem cells for trans-differentiation into corneal epithelium-like cells. Rhesus putative epidermal stem cells were isolated by type IV collagen attachment method. Flow cytometry analysis, immuno-histology and RT-PCR were conducted to identify the expression of specific markers (β1, α6 integrin, K15, K1/K10, K3/K12 and CD71) on the isolated rapid attaching cells. The isolated cells were cocultured with human corneal limbal stroma and corneal epithelial cells. After coculture, the expression of the same specific markers was evaluated in order to identify expression difference caused by the coculture conditions. K3/K12 expression was analyzed in coculture cells on day 2, 4, 6, 8 and 10. Putative epi-dermal stem cells in conditioned culture media were used as control. Putative epidermal stem cells were predominant in rapid attaching cells by type IV collagen attachment isolation. Before being co-cultured, the rhesus putative epidermal stem cells expressed K15, α6 and β1 integrin, but no CD71, K1/K10 and K3/K12. After coculture, these cells expressed K3/K12 (a marker of corneal epithelial cells), K15 and β 1 integrin, but no K1/K10. Cells being not coculture converted into terminally differentiated cells expressing K1/K10. These results indicate that rhesus putative epidermal stem cells can trans-differentiate into corneal epithelium-like cells and, therefore, may have potential therapeutic application as autologous seed cells for the construction of bioengineered corneas.

  3. Ex vivo differentiation of multipotent adult progenitor cells to skin epidermal cells

    Institute of Scientific and Technical Information of China (English)

    Ji Kaihong; Xiong Jun; Fan Lixing; Hu Kaimeng; Liu Houqi

    2009-01-01

    Objective: By establishing the indirect contact co-culture system, we studied the in vitro condition for MAPCs differentiating into epidermal cells and the transformation of MAPCs into epidermal cell phenotype. Methods: Cell culture insert membrane was used for substitute basal membrane and MAPCs, fibroblast cells (FCs) and mixture of MAPCs and epidermal cells and FCs were separately implanted into 2 sides of it. PKH26 was used to label cloned MAPCs; type Ⅳ collagen rapid adhering method was used to isolate and culture the skin epidermal cells from 1-day-old SD rat. Results: Part of the MAPCs transformed into cells expressing keratin in the presence of peripheral epithelia and FCs. Type Ⅳ collagen rapid adhering method successfully selected rats' epidermal stem cells. The mixture of the 2 kinds of cells or indirect culture might promote the differentiation through mesenchymal factors secreted by dermis FC. Conclusion: We were the first to have established the in vitro model of MAPCs differentiation into epidermal cells, in which MAPCs were transformed into epithelium-like cells.

  4. Streptococcus induces circulating CLA(+) memory T-cell-dependent epidermal cell activation in psoriasis.

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    Ferran, Marta; Galván, Ana B; Rincón, Catalina; Romeu, Ester R; Sacrista, Marc; Barboza, Erika; Giménez-Arnau, Ana; Celada, Antonio; Pujol, Ramon M; Santamaria-Babí, Luis F

    2013-04-01

    Streptococcal throat infection is associated with a specific variant of psoriasis and with HLA-Cw6 expression. In this study, activation of circulating psoriatic cutaneous lymphocyte-associated antigen (CLA)(+) memory T cells cultured together with epidermal cells occurred only when streptococcal throat extracts were added. This triggered the production of Th1, Th17, and Th22 cytokines, as well as epidermal cell mediators (CXCL8, CXCL9, CXCL10, and CXCL11). Streptococcal extracts (SEs) did not induce any activation with either CLA(-) cells or memory T cells cultured together with epidermal cells from healthy subjects. Intradermal injection of activated culture supernatants into mouse skin induced epidermal hyperplasia. SEs also induced activation when we used epidermal cells from nonlesional skin of psoriatic patients with CLA(+) memory T cells. Significant correlations were found between SE induced upregulation of mRNA expression for ifn-γ, il-17, il-22, ip-10, and serum level of antistreptolysin O in psoriatic patients. This study demonstrates the direct involvement of streptococcal infection in pathological mechanisms of psoriasis, such as IL-17 production and epidermal cell activation.

  5. Epidermal stem cells - role in normal, wounded and pathological psoriatic and cancer skin

    DEFF Research Database (Denmark)

    Kamstrup, M.; Faurschou, A.; Gniadecki, R.

    2008-01-01

    in the basal layer of the interfollicular epidermis and in the bulge region of the hair follicle play a critical role for normal tissue maintenance. In wound healing, multipotent epidermal stem cells contribute to re-epithelization. It is possible that defects in growth control of either epidermal stem cells......In this review we focus on epidermal stem cells in the normal regeneration of the skin as well as in wounded and psoriatic skin. Furthermore, we discuss current data supporting the idea of cancer stem cells in the pathogenesis of skin carcinoma and malignant melanoma. Epidermal stem cells present...

  6. Cell and molecular biology of epidermal growth factor receptor.

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    Ceresa, Brian P; Peterson, Joanne L

    2014-01-01

    The epidermal growth factor receptor (EGFR) has been one of the most intensely studied cell surface receptors due to its well-established roles in developmental biology, tissue homeostasis, and cancer biology. The EGFR has been critical for creating paradigms for numerous aspects of cell biology, such as ligand binding, signal transduction, and membrane trafficking. Despite this history of discovery, there is a continual stream of evidence that only the surface has been scratched. New ways of receptor regulation continue to be identified, each of which is a potential molecular target for manipulating EGFR signaling and the resultant changes in cell and tissue biology. This chapter is an update on EGFR-mediated signaling, and describes some recent developments in the regulation of receptor biology.

  7. Programmed Cell Death Progresses Differentially in Epidermal and Mesophyll Cells of Lily Petals.

    Directory of Open Access Journals (Sweden)

    Hiroko Mochizuki-Kawai

    Full Text Available In the petals of some species of flowers, programmed cell death (PCD begins earlier in mesophyll cells than in epidermal cells. However, PCD progression in each cell type has not been characterized in detail. We separately constructed a time course of biochemical signs and expression patterns of PCD-associated genes in epidermal and mesophyll cells in Lilium cv. Yelloween petals. Before visible signs of senescence could be observed, we found signs of PCD, including DNA degradation and decreased protein content in mesophyll cells only. In these cells, the total proteinase activity increased on the day after anthesis. Within 3 days after anthesis, the protein content decreased by 61.8%, and 22.8% of mesophyll cells was lost. A second peak of proteinase activity was observed on day 6, and the number of mesophyll cells decreased again from days 4 to 7. These biochemical and morphological results suggest that PCD progressed in steps during flower life in the mesophyll cells. PCD began in epidermal cells on day 5, in temporal synchrony with the time course of visible senescence. In the mesophyll cells, the KDEL-tailed cysteine proteinase (LoCYP and S1/P1 nuclease (LoNUC genes were upregulated before petal wilting, earlier than in epidermal cells. In contrast, relative to that in the mesophyll cells, the expression of the SAG12 cysteine proteinase homolog (LoSAG12 drastically increased in epidermal cells in the final stage of senescence. These results suggest that multiple PCD-associated genes differentially contribute to the time lag of PCD progression between epidermal and mesophyll cells of lily petals.

  8. Growth activity of epidermal cells from different parts of human body

    Institute of Scientific and Technical Information of China (English)

    CHAI Jia-ke; SHENG Zhi-yong; MA Zhong-feng; YANG Hong-ming; LIU Qiang; Liang Li-ming

    2007-01-01

    Background Most epidermal cells used in skin tissue engineering are obtained from the skins of fetuses or prepuces,which can not be widely used in culturing and transplanting autologous epidermis for patients with extensive burn wounds. To solve the problem, in this study, we cultured epidermal cells from different parts of human body in vitro, and detected their growth activity.Methods Normal epidermal cells obtained from the prepuce, scalp, and axilla of male patients, were cultured and passaged. Their growth characteristics including adherent rate and growth activity were compared. Data were analyzed by homogeneity test of variance.Results In primary culture, the growth of epidermal cells from the prepuce was significantly faster than that of the epidermal cells from the scalp and axilla. In the cells obtained from the prepuce, 80% confluence was achieved on day 12, while on day 16 and day 20 in the cells from the scalp and axilla, respectively. However, no significant difference was detected in their growth and proliferation in the second passage.Conclusions Although the growth of epidermal cells obtained from the scalp and axilla is slower than that from the prepuce in primary culture, stable cell line can be established and used in preparation of auto-epidermal grafts for patients with extensive burn wounds. Therefore, the scalp and axillary skin should be considered as important sources of epidermal cells other than the prepuce.

  9. Growth activity of epidermal cells from different parts of human body.

    Science.gov (United States)

    Chai, Jia-ke; Sheng, Zhi-yong; Ma, Zhong-feng; Yang, Hong-ming; Liu, Qiang; Liang, Li-ming

    2007-08-20

    Most epidermal cells used in skin tissue engineering are obtained from the skins of fetuses or prepuces, which can not be widely used in culturing and transplanting autologous epidermis for patients with extensive burn wounds. To solve the problem, in this study, we cultured epidermal cells from different parts of human body in vitro, and detected their growth activity. Normal epidermal cells obtained from the prepuce, scalp, and axilla of male patients, were cultured and passaged. Their growth characteristics including adherent rate and growth activity were compared. Data were analyzed by homogeneity test of variance. In primary culture, the growth of epidermal cells from the prepuce was significantly faster than that of the epidermal cells from the scalp and axilla. In the cells obtained from the prepuce, 80% confluence was achieved on day 12, while on day 16 and day 20 in the cells from the scalp and axilla, respectively. However, no significant difference was detected in their growth and proliferation in the second passage. Although the growth of epidermal cells obtained from the scalp and axilla is slower than that from the prepuce in primary culture, stable cell line can be established and used in preparation of auto-epidermal grafts for patients with extensive burn wounds. Therefore, the scalp and axillary skin should be considered as important sources of epidermal cells other than the prepuce.

  10. Epidermal development in mammals: key regulators, signals from beneath, and stem cells.

    Science.gov (United States)

    Liu, Shuang; Zhang, Huishan; Duan, Enkui

    2013-05-24

    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.

  11. Amnioserosa cell constriction but not epidermal actin cable tension autonomously drives dorsal closure.

    Science.gov (United States)

    Pasakarnis, Laurynas; Frei, Erich; Caussinus, Emmanuel; Affolter, Markus; Brunner, Damian

    2016-11-01

    Tissue morphogenesis requires coordination of multiple force-producing components. During dorsal closure in fly embryogenesis, an epidermis opening closes. A tensioned epidermal actin/MyosinII cable, which surrounds the opening, produces a force that is thought to combine with another MyosinII force mediating apical constriction of the amnioserosa cells that fill the opening. A model proposing that each force could autonomously drive dorsal closure was recently challenged by a model in which the two forces combine in a ratchet mechanism. Acute force elimination via selective MyosinII depletion in one or the other tissue shows that the amnioserosa tissue autonomously drives dorsal closure while the actin/MyosinII cable cannot. These findings exclude both previous models, although a contribution of the ratchet mechanism at dorsal closure onset remains likely. This shifts the current view of dorsal closure being a combinatorial force-component system to a single tissue-driven closure event.

  12. Langerhans Cells Facilitate UVB-induced Epidermal Carcinogenesis

    Science.gov (United States)

    Lewis, Julia M.; Bürgler, Christina D.; Freudzon, Marianna; Golubets, Kseniya; Gibson, Juliet F.; Filler, Renata B.; Girardi, Michael

    2015-01-01

    Ultraviolet B (UVB) light is considered the major environmental inducer of human keratinocyte DNA mutations, including within the tumor-suppressor gene p53, and chronic exposure is associated with cutaneous squamous cell carcinoma (SCC) formation. Langerhans cells (LC) comprise a dendritic network within the suprabasilar epidermis, yet the role of LC in UVB-induced carcinogenesis is largely unknown. Herein, we show that LC-intact epidermis develops UVB-induced tumors more readily than LC-deficient epidermis. While levels of epidermal cyclopyrimidine dimers (CPD) following acute UVB exposure are equivalent in the presence or absence of LC, chronic UVB-induced p53 mutant clonal islands expand more readily in association with LC which remain largely intact and are preferentially found in proximity to the expanding mutant keratinocyte populations. The observed LC facilitation of mutant p53 clonal expansion is completely αβ and γδ T-cell independent, and is associated with increased intraepidermal expression of interleukin (IL)-22 and the presence of group 3 innate lymphoid cells (ILC3). These data demonstrate that LC play a key role in UVB-induced cutaneous carcinogenesis, and suggest that LC locally stimulate keratinocyte proliferation and innate immune cells that provoke tumor outgrowth. PMID:26053049

  13. Identification of a population of epidermal squamous cell carcinoma cells with enhanced potential for tumor formation.

    Directory of Open Access Journals (Sweden)

    Gautam Adhikary

    Full Text Available Epidermal squamous cell carcinoma is among the most common cancers in humans. These tumors are comprised of phenotypically diverse populations of cells that display varying potential for proliferation and differentiation. An important goal is identifying cells from this population that drive tumor formation. To enrich for tumor-forming cells, cancer cells were grown as spheroids in non-attached conditions. We show that spheroid-selected cells form faster growing and larger tumors in immune-compromised mice as compared to non-selected cells. Moreover, spheroid-selected cells gave rise to tumors following injection of as few as one hundred cells, suggesting these cells have enhanced tumor-forming potential. Cells isolated from spheroid-selected tumors retain an enhanced ability to grow as spheroids when grown in non-attached culture conditions. Thus, these tumor-forming cells retain their phenotype following in vivo passage as tumors. Detailed analysis reveals that spheroid-selected cultures are highly enriched for expression of epidermal stem cell and embryonic stem cell markers, including aldehyde dehydrogenase 1, keratin 15, CD200, keratin 19, Oct4, Bmi-1, Ezh2 and trimethylated histone H3. These studies indicate that a subpopulation of cells that possess stem cell-like properties and express stem cell markers can be derived from human epidermal cancer cells and that these cells display enhanced ability to drive tumor formation.

  14. Rapid and dynamic subcellular reorganization following mechanical stimulation of Arabidopsis epidermal cells mimics responses to fungal and oomycete attack

    Directory of Open Access Journals (Sweden)

    Takemoto Daigo

    2008-06-01

    Full Text Available Abstract Background Plant cells respond to the presence of potential fungal or oomycete pathogens by mounting a basal defence response that involves aggregation of cytoplasm, reorganization of cytoskeletal, endomembrane and other cell components and development of cell wall appositions beneath the infection site. This response is induced by non-adapted, avirulent and virulent pathogens alike, and in the majority of cases achieves penetration resistance against the microorganism on the plant surface. To explore the nature of signals that trigger this subcellular response and to determine the timing of its induction, we have monitored the reorganization of GFP-tagged actin, microtubules, endoplasmic reticulum (ER and peroxisomes in Arabidopsis plants – after touching the epidermal surface with a microneedle. Results Within 3 to 5 minutes of touching the surface of Arabidopsis cotyledon epidermal cells with fine glass or tungsten needles, actin microfilaments, ER and peroxisomes began to accumulate beneath the point of contact with the needle. Formation of a dense patch of actin was followed by focusing of actin cables on the site of contact. Touching the cell surface induced localized depolymerization of microtubules to form a microtubule-depleted zone surrounding a dense patch of GFP-tubulin beneath the needle tip. The concentration of actin, GFP-tubulin, ER and peroxisomes remained focused on the contact site as the needle moved across the cell surface and quickly dispersed when the needle was removed. Conclusion Our results show that plant cells can detect the gentle pressure of a microneedle on the epidermal cell surface and respond by reorganizing subcellular components in a manner similar to that induced during attack by potential fungal or oomycete pathogens. The results of our study indicate that during plant-pathogen interactions, the basal defence response may be induced by the plant's perception of the physical force exerted by the

  15. Shavenbaby couples patterning to epidermal cell shape control.

    Directory of Open Access Journals (Sweden)

    Hélène Chanut-Delalande

    2006-09-01

    Full Text Available It is well established that developmental programs act during embryogenesis to determine animal morphogenesis. How these developmental cues produce specific cell shape during morphogenesis, however, has remained elusive. We addressed this question by studying the morphological differentiation of the Drosophila epidermis, governed by a well-known circuit of regulators leading to a stereotyped pattern of smooth cells and cells forming actin-rich extensions (trichomes. It was shown that the transcription factor Shavenbaby plays a pivotal role in the formation of trichomes and underlies all examined cases of the evolutionary diversification of their pattern. To gain insight into the mechanisms of morphological differentiation, we sought to identify shavenbaby's downstream targets. We show here that Shavenbaby controls epidermal cell shape, through the transcriptional activation of different classes of cellular effectors, directly contributing to the organization of actin filaments, regulation of the extracellular matrix, and modification of the cuticle. Individual inactivation of shavenbaby's targets produces distinct trichome defects and only their simultaneous inactivation prevent trichome formation. Our data show that shavenbaby governs an evolutionarily conserved developmental module consisting of a set of genes collectively responsible for trichome formation, shedding new light on molecular mechanisms acting during morphogenesis and the way they can influence evolution of animal forms.

  16. Epidermal Growth Factor Receptor Cell Survival Signaling Requires Phosphatidylcholine Biosynthesis

    Directory of Open Access Journals (Sweden)

    Matt Crook

    2016-11-01

    Full Text Available Identification of pro-cell survival signaling pathways has implications for cancer, cardiovascular, and neurodegenerative disease. We show that the Caenorhabditis elegans epidermal growth factor receptor LET-23 (LET-23 EGFR has a prosurvival function in counteracting excitotoxicity, and we identify novel molecular players required for this prosurvival signaling. uv1 sensory cells in the C. elegans uterus undergo excitotoxic death in response to activation of the OSM-9/OCR-4 TRPV channel by the endogenous agonist nicotinamide. Activation of LET-23 EGFR can effectively prevent this excitotoxic death. We investigate the roles of signaling pathways known to act downstream of LET-23 EGFR in C. elegans and find that the LET-60 Ras/MAPK pathway, but not the IP3 receptor pathway, is required for efficient LET-23 EGFR activity in its prosurvival function. However, activation of LET-60 Ras/MAPK pathway does not appear to be sufficient to fully mimic LET-23 EGFR activity. We screen for genes that are required for EGFR prosurvival function and uncover a role for phosphatidylcholine biosynthetic enzymes in EGFR prosurvival function. Finally, we show that exogenous application of phosphatidylcholine is sufficient to prevent some deaths in this excitotoxicity model. Our work implicates regulation of lipid synthesis downstream of EGFR in cell survival and death decisions.

  17. Epidermal Patterning Genes Impose Non-cell Autonomous Cell Size Determination and have Additional Roles in Root Meristem Size Control

    Institute of Scientific and Technical Information of China (English)

    Christian L?fke; Kai Dünser; Jürgen Kleine-Vehn

    2013-01-01

    The regulation of cellular growth is of vital importance for embryonic and postembryonic patterning. Growth regulation in the epidermis has importance for organ growth rates in roots and shoots, proposing epidermal cells as an interesting model for cellular growth regulation. Here we assessed whether the root epidermis is a suitable model system to address cell size determination. In Arabidopsis thaliana L., root epidermal cells are regularly spaced in neighbouring tricho-(root hair) and atrichoblast (non-hair) cells, showing already distinct cell size regulation in the root meristem. We determined cell sizes in the root meristem and at the onset of cellular elongation, revealing that not only division rates but also cellular shape is distinct in tricho-and atrichoblasts. Intriguingly, epidermal-patterning mutants, failing to define differential vacuolization in neighbouring epidermal cell files, also display non-differential growth. Using these epidermal-patterning mutants, we show that polarized growth behaviour of epidermal tricho-and atrichoblast is interdependent, suggesting non-cell autonomous signals to integrate tissue expansion. Besides the interweaved cell-type-dependent growth mechanism, we reveal an additional role for epidermal patterning genes in root meristem size and organ growth regulation. We conclude that epidermal cells represent a suitable model system to study cell size determination and interdependent tissue growth.

  18. Basal cell carcinoma arising on a verrucous epidermal nevus: a case report.

    Science.gov (United States)

    Viana, Analia; Aguinaga, Felipe; Marinho, Flauberto; Rodrigues, Rosangela; Cuzzi, Tullia; Ramos-E-Silva, Marcia

    2015-01-01

    We report a case of basal cell carcinoma that appeared from an epidermal verrucous nevus in a 61-year-old patient. The onset of basal cell carcinoma in sebaceous nevi, basal cell nevi and dysplastic nevi is relatively common, but it is rarely associated with epidermal verrucous nevi. There is no consensus on whether the two lesions have a common cellular origin or whether they merely represent a collision of two distinct tumors. Since this association - as with other malignant tumors - is rare, there is no need for prophylactic removal of epidermal verrucous nevi.

  19. Regulation of epidermal Langerhans cell migration by lactoferrin.

    Science.gov (United States)

    Cumberbatch, M; Dearman, R J; Uribe-Luna, S; Headon, D R; Ward, P P; Conneely, O M; Kimber, I

    2000-05-01

    Lactoferrin (LF) is a member of the transferrin family of iron-binding glycoproteins to which several anti-inflammatory functions have been ascribed. LF has been shown to down-regulate expression of the pro-inflammatory cytokine tumour necrosis factor-alpha (TNF-alpha), although the possibility has been raised that the activity of LF in this regard was indirect and secondary to its ability to bind to and inactivate the bacterial lipopolysaccharide (LPS) used to induce cytokine production. However, the identification of putative membrane receptors for LF raises the possibility that the interaction of LF with its receptor may be one important route through which this protein exerts anti-inflammatory activity. In the present investigations the biological properties of LF have been examined in a model of cutaneous immune function where the allergen-induced migration of epidermal Langerhans cells (LC) from the skin and their subsequent accumulation as dendritic cells (DC) in skin-draining lymph nodes are known to be dependent upon the de novo synthesis of TNF-alpha, but independent of exogenous LPS. Consistent with the protein having direct anti-inflammatory properties, it was found that the intradermal injection of recombinant murine LF (either iron-saturated or iron-depleted LF) inhibited significantly allergen (oxazolone) -induced LC migration and DC accumulation. That these inhibitory effects were secondary to the inhibition of local TNF-alpha synthesis was suggested by the findings that first, LF was unable to inhibit LC migration induced by intradermal injection of TNF-alpha itself, and second, that migration stimulated by local administration of another epidermal cytokine, interleukin 1beta, which is also dependent upon TNF-alpha production, was impaired significantly by prior treatment with LF. Finally, immunohistochemical analyses demonstrated the presence of LF in skin, associated primarily with keratinocytes. Collectively these data support the possession by

  20. Transplantation of autologous noncultured epidermal cell suspension in treatment of patients with stable vitiligo

    Institute of Scientific and Technical Information of China (English)

    XU Ai-e; WEI Xiao-dong; CHENG Dong-qing; ZHOU He-fen; QIAN Guo-pei

    2005-01-01

    @@ Treatment of vitiligo by transplantation of noncultured melanocytes containing keratino-cytes has been successful since 1992,1 We report the encouraging results of autologous epidermal cell suspension in the treatment of 24 patients with stable vitiligo since 1998.

  1. Fatty acid metabolism studies of human epidermal cell cultures.

    Science.gov (United States)

    Marcelo, C L; Dunham, W R

    1993-12-01

    Adult human epidermal keratinocytes grow rapidly in medium that is essential fatty acid (EFA)-deficient. In this medium they exhibit decreased amounts of the fatty acids, 18:2, 20:3, 20:4, and contain increased amounts of monounsaturated fatty acids. [14C]- and [3H]acetate and radiolabeled fatty acids, 16:0, 18:2, and 20:4 were used to study the fatty acid metabolism of these cells. Label from acetate appeared in 14- to 20-carbon fatty acids, both saturated and monounsaturated. No label was seen in the essential fatty acid 18:2, 18:3, and 20:4. Radiolabel from [9, 10-3H]palmitic acid (16:0) was detected in 16:0, 16:1, 18:0, and 18:1. [14C]linoleic acid (18:2) was converted to 18:3, 20:2, 20:3, and 20:4, demonstrating delta 6 and delta 5 desaturase activity in keratinocytes. Label from acetate, 16:0, or 18:2 was found mostly in the cellular phospholipids while only one third of the label from [14C]arachidonic was found in the phospholipids. [14C]acetate and [14C]18:2 time course data were used to construct a model of the metabolism of these reactants, using coupled, first-order differential equations. The data show that EFA-deficient keratinocytes metabolize fatty acids using pathways previously found in liver; they suggest the positioning of 18:2 desaturase and 18:3 elongase near the plasma membrane; they indicate that for the synthesis of nonessential fatty acids the formation of 18:0 from 16:0 is the rate-determining step; and they show that the conversion of 18:2 to 20:3 is rapid. These experiments demonstrate a method to study lipid enzyme kinetics in living cells.

  2. Regenerative and reparative effects of human chorion-derived stem cell conditioned medium on photo-aged epidermal cells.

    Science.gov (United States)

    Li, Qiankun; Chen, Yan; Ma, Kui; Zhao, Along; Zhang, Cuiping; Fu, Xiaobing

    2016-01-01

    Epidermal cells are an important regenerative source for skin wound healing. Aged epidermal cells have a low ability to renew themselves and repair skin injury. Ultraviolet (UV) radiation, particularly UVB, can cause photo-aging of the skin by suppressing the viability of human epidermal cells. A chorion-derived stem cell conditioned medium (CDSC-CNM) is thought to have regenerative properties. This study aimed to determine the regenerative effects of CDSC-CNM on UVB-induced photo-aged epidermal cells. Epidermal cells were passaged four times and irradiated with quantitative UVB, and non-irradiated cells served as a control group. Cells were then treated with different concentrations of CDSC-CNM. Compared to the non-irradiated group, the proliferation rates and migration rates of UVB-induced photo-aged epidermal cells significantly decreased (p cells significantly improved their viability, and their ROS generation and DNA damage decreased. The secretory factors in CDSC-CNM, including epidermal growth factor (EGF), transforming growth factor-β (TGF-β), interleukin (IL)-6, and IL-8 and the related signaling pathway protein levels, increased compared to the control medium (CM). The potential regenerative and reparative effects of CDSC-CNM indicate that it may be a candidate material for the treatment of prematurely aged skin. The functions of the secretory factors and the mechanisms of CDSC-CNM therapy deserve further attention.

  3. The dermis contains langerin+ dendritic cells that develop and function independently of epidermal Langerhans cells.

    Science.gov (United States)

    Poulin, Lionel Franz; Henri, Sandrine; de Bovis, Béatrice; Devilard, Elisabeth; Kissenpfennig, Adrien; Malissen, Bernard

    2007-12-24

    Langerhans cells (LCs) constitute a subset of dendritic cells (DCs) that express the lectin langerin and that reside in their immature state in epidermis. Paradoxically, in mice permitting diphtheria toxin (DT)-mediated ablation of LCs, epidermal LCs reappeared with kinetics that lagged behind that of their putative progeny found in lymph nodes (LNs). Using bone marrow (BM) chimeras, we showed that a major fraction of the langerin(+), skin-derived DCs found in LNs originates from a developmental pathway that is independent from that of epidermal LCs. This pathway, the existence of which was unexpected, originates in the dermis and gives rise to langerin(+) dermal DCs (DDCs) that should not be confused with epidermal LCs en route to LNs. It explains that after DT treatment, some langerin(+), skin-derived DCs reappear in LNs long before LC-derived DCs. Using CD45 expression and BrdU-labeling kinetics, both LCs and langerin(+) DDCs were found to coexist in wild-type mice. Moreover, DT-mediated ablation of epidermal LCs opened otherwise filled niches and permitted repopulation of adult noninflammatory epidermis with BM-derived LCs. Our results stress that the langerin(+) DC network is more complex than originally thought and have implications for the development of transcutaneous vaccines and the improvement of humanized mouse models.

  4. Evolution of the clonogenic potential of human epidermal stem/progenitor cells with age

    Directory of Open Access Journals (Sweden)

    Zobiri O

    2012-02-01

    Full Text Available Olivia Zobiri, Nathalie Deshayes, Michelle Rathman-JosserandDepartment of Biological Research, L'Oréal Advanced Research, Clichy Cedex, FranceAbstract: A number of clinical observations have indicated that the regenerative potential and overall function of the epidermis is modified with age. The epidermis becomes thinner, repairs itself less efficiently after wounding, and presents modified barrier function recovery. In addition, the dermal papillae flatten out with increasing age, suggesting a modification in the interaction between epidermal and dermal compartments. As the epidermal regenerative capacity is dependent upon stem and progenitor cell function, it is naturally of interest to identify and understand age-related changes in these particular keratinocyte populations. Previous studies have indicated that the number of stem cells does not decrease with age in mouse models but little solid evidence is currently available concerning human skin. The objective of this study was to evaluate the clonogenic potential of keratinocyte populations isolated from the epidermis of over 50 human donors ranging from 18 to 71 years old. The data indicate that the number of epidermal cells presenting high regenerative potential does not dramatically decline with age in human skin. The authors believe that changes in the microenvironment controlling epidermal basal cell activity are more likely to explain the differences in epidermal function observed with increasing age.Keywords: skin, epidermal stem cells, aging, colony-forming efficiency test

  5. In situ visualization of intracellular morphology of epidermal cells using stimulated Raman scattering microscopy

    Science.gov (United States)

    Egawa, Mariko; Tokunaga, Kyoya; Hosoi, Junichi; Iwanaga, Shinya; Ozeki, Yasuyuki

    2016-08-01

    Visualization of epidermal cells is important because the differentiation patterns of keratinocytes (KCs) are considered to be related to the functions and condition of skin. Optical microscopy has been widely used to investigate epidermal cells, but its applicability is still limited because of the need for sample fixation and staining. Here, we report our staining-free observation of epidermal cells in both tissue and culture by stimulated Raman scattering (SRS) microscopy that provides molecular vibrational contrast. SRS allowed us to observe a variety of cellular morphologies in skin tissue, including ladder-like structures in the spinous layer, enucleation of KCs in the granular layer, and three-dimensional cell column structures in the stratum corneum. We noticed that some cells in the spinous layer had a brighter signal in the cytoplasm than KCs. To examine the relevance of the observation of epidermal layers, we also observed cultured epidermal cells, including KCs at various differentiation stages, melanocytes, and Langerhans cell-like cells. Their SRS images also demonstrated various morphologies, suggesting that the morphological differences observed in tissue corresponded to the cell lineage. These results indicate the possible application of SRS microscopy to dermatological investigation of cell lineages and types in the epidermis by cellular-level analysis.

  6. Ultrastructure of the Epidermal Cell Wall and Cuticle of Tomato Fruit (Solanum lycopersicum L.) during Development.

    Science.gov (United States)

    Segado, Patricia; Domínguez, Eva; Heredia, Antonio

    2016-02-01

    The epidermis plays a pivotal role in plant development and interaction with the environment. However, it is still poorly understood, especially its outer epidermal wall: a singular wall covered by a cuticle. Changes in the cuticle and cell wall structures are important to fully understand their functions. In this work, an ultrastructure and immunocytochemical approach was taken to identify changes in the cuticle and the main components of the epidermal cell wall during tomato fruit development. A thin and uniform procuticle was already present before fruit set. During cell division, the inner side of the procuticle showed a globular structure with vesicle-like particles in the cell wall close to the cuticle. Transition between cell division and elongation was accompanied by a dramatic increase in cuticle thickness, which represented more than half of the outer epidermal wall, and the lamellate arrangement of the non-cutinized cell wall. Changes in this non-cutinized outer wall during development showed specific features not shared with other cell walls. The coordinated nature of the changes observed in the cuticle and the epidermal cell wall indicate a deep interaction between these two supramolecular structures. Hence, the cuticle should be interpreted within the context of the outer epidermal wall. © 2016 American Society of Plant Biologists. All Rights Reserved.

  7. From diffuse growth to planar polarity in Arabidopsis root epidermal cells

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    Daria eBalcerowicz

    2015-12-01

    Full Text Available Plant roots fulfill important functions as they serve in water and nutrient uptake, provide anchorage of the plant body in the soil and in some species form the site of symbiotic interactions with soil-living biota. Root hairs, tubular-shaped outgrowths of specific epidermal cells, significantly increase the root's surface area and aid in these processes. In this review we focus on the molecular mechanisms that determine the hair and non-hair cell fate of epidermal cells and that define the site on the epidermal cell where the root hair will be initiated (= planar polarity determination. In the model plant Arabidopsis, trichoblast and atrichoblast cell fate results from intra- and intercellular position-dependent signaling and from complex feedback loops that ultimately regulate GL2 expressing and non-expressing cells. When epidermal cells reach the end of the root expansion zone, root hair promoting transcription factors dictate the establishment of polarity within epidermal cells followed by the selection of the root hair initiation site at the more basal part of the trichoblast. Molecular players in the abovementioned processes as well as the role of phytohormones are discussed, and open areas for future experiments are identified.

  8. Differential gene expression in individual papilla-resistant and powdery mildew-infected barley epidermal cells

    DEFF Research Database (Denmark)

    Gjetting, T.; Carver, Timothy L. W.; Skøt, Leif

    2004-01-01

    Resistance and susceptibility in barley to the powdery mildew fungus (Blumeria graminis f. sp. hordei) is determined at the single-cell level. Even in genetically compatible interactions, attacked plant epidermal cells defend themselves against attempted fungal penetration by localized responses...... leading to papilla deposition and reinforcement of their cell wall. This conveys a race-nonspecific form of resistance. However, this defense is not complete, and a proportion of penetration attempts succeed in infection. The resultant mixture of infected and uninfected leaf cells makes it impossible...... to relate powdery mildew-induced gene expression in whole leaves or even dissected epidermal tissues to resistance or susceptibility. A method for generating transcript profiles from individual barley epidermal cells was established and proven useful for analyzing resistant and successfully infected cells...

  9. In situ localization of epidermal stem cells using a novel multi epitope ligand cartography approach.

    Science.gov (United States)

    Ruetze, Martin; Gallinat, Stefan; Wenck, Horst; Deppert, Wolfgang; Knott, Anja

    2010-06-01

    Precise knowledge of the frequency and localization of epidermal stem cells within skin tissue would further our understanding of their role in maintaining skin homeostasis. As a novel approach we used the recently developed method of multi epitope ligand cartography, applying a set of described putative epidermal stem cell markers. Bioinformatic evaluation of the data led to the identification of several discrete basal keratinocyte populations, but none of them displayed the complete stem cell marker set. The distribution of the keratinocyte populations within the tissue was remarkably heterogeneous, but determination of distance relationships revealed a population of quiescent cells highly expressing p63 and the integrins alpha(6)/beta(1) that represent origins of a gradual differentiation lineage. This population comprises about 6% of all basal cells, shows a scattered distribution pattern and could also be found in keratinocyte holoclone colonies. The data suggest that this population identifies interfollicular epidermal stem cells.

  10. Reduced trisialoganglioside synthesis in chemically but not mos-transformed mouse epidermal cells

    Energy Technology Data Exchange (ETDEWEB)

    Srinivas, L.; Colburn, N.H.

    1984-04-01

    A specific decrease in the net de novo synthesis ((1-14C)-glucosamine incorporation) of cell surface trisialoganglioside (GT) occurs in preneoplastic mouse JB6 epidermal cells in response to tumor-promoting phorbol esters, mezerein, or epidermal growth factor, all of which promote neoplastic transformation in JB6 cells, but not in response to the bladder promoter sodium cyclamate, a nonpromoter in JB6 cells. The ganglioside showing elevated synthesis after mezerein or epidermal growth factor exposure is monosialoganglioside 1, whereas disialoganglioside 1b synthesis is elevated after phorbol ester exposure. Primary mouse epidermal cells and putatively initiated epidermal cell lines selected for their resistance to induction of terminal differentiation by high calcium are resistant to promotion of anchorage-independent transformation by 2-week exposure to 12-O-tetradecanoylphorbol-13-acetate. In both cell types, little or no decrease in GT synthesis occurs in response to short-term 12-O-tetradecanoylphorbol-13-acetate exposure, thus extending further our previous observation that this GT response is restricted to promotable cells. A decreased synthesis of GT also occurs consistently in cell lines transformed by 12-O-tetradecanoylphorbol-13-acetate or N-methyl-N-nitro-nitrosoguanidine as compared with their nontransformed counterparts but not in cell lines transformed by a cloned integrated murine sarcoma provirus containing the oncogenic sequence v-mos. Thus, reduced cell surface GT synthesis may be important both in the induction and in the maintenance of the chemically transformed but not viral oncogene mos-transformed phenotype in mouse epidermal cells.

  11. Homologs of SCAR/WAVE complex components are required for epidermal cell morphogenesis in rice.

    Science.gov (United States)

    Zhou, Wenqi; Wang, Yuchuan; Wu, Zhongliang; Luo, Liang; Liu, Ping; Yan, Longfeng; Hou, Suiwen

    2016-07-01

    Filamentous actins (F-actins) play a vital role in epidermal cell morphogenesis. However, a limited number of studies have examined actin-dependent leaf epidermal cell morphogenesis events in rice. In this study, two recessive mutants were isolated: less pronounced lobe epidermal cell2-1 (lpl2-1) and lpl3-1, whose leaf and stem epidermis developed a smooth surface, with fewer serrated pavement cell (PC) lobes, and decreased papillae. The lpl2-1 also exhibited irregular stomata patterns, reduced plant height, and short panicles and roots. Molecular genetic studies demonstrated that LPL2 and LPL3 encode the PIROGI/Specifically Rac1-associated protein 1 (PIR/SRA1)-like and NCK-associated protein 1 (NAP1)-like proteins, respectively, two components of the suppressor of cAMP receptor/Wiskott-Aldrich syndrome protein-family verprolin-homologous protein (SCAR/WAVE) regulatory complex involved in actin nucleation and function. Epidermal cells exhibited abnormal arrangement of F-actins in both lpl2 and lpl3 expanding leaves. Moreover, the distorted trichomes of Arabidopsis pir could be partially restored by an overexpression of LPL2 A yeast two-hybrid assay revealed that LPL2 can directly interact with LPL3 in vitro Collectively, the results indicate that LPL2 and LPL3 are two functionally conserved homologs of the SCAR/WAVE complex components, and that they play an important role in controlling epidermal cell morphogenesis in rice by organising F-actin.

  12. THE EFFECT OF MEBT/MEBO ON EPIDERMAL REGENERATIVE STEM CELLS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective: To investigate the mechanism of the effect of Moist Exposed Burn Therapy (MEBT) and Moist Exposed Burn Ointment (MEBO) on the spontaneous repair and healing of superficial third degree burn wound involving fatty layer. Method: A series of skin tissue samples were taken from deep burn wounds of 2 cases. Immunocytochemistry method, biotin avidin DCS system, and indirect immunofluorescence technique were applied. Mouse anti human keratin type 19 monoclonal antibody was used to detect regenerative epidermal stem cells in wound tissues. Results: Epidermal regenerative stem cells emerged at 24 hours post burn, and the number of epidermal regenerative stem cell increased on day 4 post burn. On days 7 and 14 post burn, the number of epidermal stem cells increased to the peak level. On days 21 and 28 post burn, it decreased and disappeared gradually as burn wound progressed to healing. Conclusion: MEBT/MEBO has the effect of promoting the activation and proliferation of epidermal regenerative stem cells in the residual viable tissue of superficial full thickness burn wound, and these stem cells play an unique role in spontaneous wound healing of deep burn.

  13. Epidermal Th22 and Tc17 Cells Form a Localized Disease Memory in Clinically Healed Psoriasis

    Science.gov (United States)

    Cheuk, Stanley; Wikén, Maria; Blomqvist, Lennart; Nylén, Susanne; Talme, Toomas; Ståhle, Mona

    2014-01-01

    Psoriasis is a common and chronic inflammatory skin disease in which T cells play a key role. Effective treatment heals the skin without scarring, but typically psoriasis recurs in previously affected areas. A pathogenic memory within the skin has been proposed, but the nature of such site-specific disease memory is unknown. Tissue-resident memory T (TRM) cells have been ascribed a role in immunity after resolved viral skin infections. Because of their localization in the epidermal compartment of the skin, TRM may contribute to tissue pathology during psoriasis. In this study, we investigated whether resolved psoriasis lesions contain TRM cells with the ability to maintain and potentially drive recurrent disease. Three common and effective therapies, narrowband-UVB treatment and long-term biologic treatment systemically inhibiting TNF-α or IL-12/23 signaling were studied. Epidermal T cells were highly activated in psoriasis and a high proportion of CD8 T cells expressed TRM markers. In resolved psoriasis, a population of cutaneous lymphocyte–associated Ag, CCR6, CD103, and IL-23R expressing epidermal CD8 T cells was highly enriched. Epidermal CD8 T cells expressing the TRM marker CD103 responded to ex vivo stimulation with IL-17A production and epidermal CD4 T cells responded with IL-22 production after as long as 6 y of TNF-α inhibition. Our data suggest that epidermal TRM cells are retained in resolved psoriasis and that these cells are capable of producing cytokines with a critical role in psoriasis pathogenesis. We provide a potential mechanism for a site-specific T cell–driven disease memory in psoriasis. PMID:24610014

  14. Abscisic acid induces ectopic outgrowth in epidermal cells through cortical microtubule reorganization in Arabidopsis thaliana

    Science.gov (United States)

    Takatani, Shogo; Hirayama, Takashi; Hashimoto, Takashi; Takahashi, Taku; Motose, Hiroyasu

    2015-01-01

    Abscisic acid (ABA) regulates seed maturation, germination and various stress responses in plants. The roles of ABA in cellular growth and morphogenesis, however, remain to be explored. Here, we report that ABA induces the ectopic outgrowth of epidermal cells in Arabidopsis thaliana. Seedlings of A. thaliana germinated and grown in the presence of ABA developed ectopic protrusions in the epidermal cells of hypocotyls, petioles and cotyledons. One protrusion was formed in the middle of each epidermal cell. In the hypocotyl epidermis, two types of cell files are arranged alternately into non-stoma cell files and stoma cell files, ectopic protrusions being restricted to the non-stoma cell files. This suggests the presence of a difference in the degree of sensitivity to ABA or in the capacity of cells to form protrusions between the two cell files. The ectopic outgrowth was suppressed in ABA insensitive mutants, whereas it was enhanced in ABA hypersensitive mutants. Interestingly, ABA-induced ectopic outgrowth was also suppressed in mutants in which microtubule organization was compromised. Furthermore, cortical microtubules were disorganized and depolymerized by the ABA treatment. These results suggest that ABA signaling induces ectopic outgrowth in epidermal cells through microtubule reorganization. PMID:26068445

  15. Evolution of the clonogenic potential of human epidermal stem/progenitor cells with age.

    Science.gov (United States)

    Zobiri, Olivia; Deshayes, Nathalie; Rathman-Josserand, Michelle

    2012-01-01

    A number of clinical observations have indicated that the regenerative potential and overall function of the epidermis is modified with age. The epidermis becomes thinner, repairs itself less efficiently after wounding, and presents modified barrier function recovery. In addition, the dermal papillae fatten out with increasing age, suggesting a modification in the interaction between epidermal and dermal compartments. As the epidermal regenerative capacity is dependent upon stem and progenitor cell function, it is naturally of interest to identify and understand age-related changes in these particular keratinocyte populations. Previous studies have indicated that the number of stem cells does not decrease with age in mouse models but little solid evidence is currently available concerning human skin. The objective of this study was to evaluate the clonogenic potential of keratinocyte populations isolated from the epidermis of over 50 human donors ranging from 18 to 71 years old. The data indicate that the number of epidermal cells presenting high regenerative potential does not dramatically decline with age in human skin. The authors believe that changes in the microenvironment controlling epidermal basal cell activity are more likely to explain the differences in epidermal function observed with increasing age.

  16. p63 and Brg1 control developmentally regulated higher-order chromatin remodelling at the epidermal differentiation complex locus in epidermal progenitor cells

    Science.gov (United States)

    Mardaryev, Andrei N.; Gdula, Michal R.; Yarker, Joanne L.; Emelianov, Vladimir N.; Poterlowicz, Krzysztof; Sharov, Andrey A.; Sharova, Tatyana Y.; Scarpa, Julie A.; Chambon, Pierre; Botchkarev, Vladimir A.; Fessing, Michael Y.

    2014-01-01

    Chromatin structural states and their remodelling, including higher-order chromatin folding and three-dimensional (3D) genome organisation, play an important role in the control of gene expression. The role of 3D genome organisation in the control and execution of lineage-specific transcription programmes during the development and differentiation of multipotent stem cells into specialised cell types remains poorly understood. Here, we show that substantial remodelling of the higher-order chromatin structure of the epidermal differentiation complex (EDC), a keratinocyte lineage-specific gene locus on mouse chromosome 3, occurs during epidermal morphogenesis. During epidermal development, the locus relocates away from the nuclear periphery towards the nuclear interior into a compartment enriched in SC35-positive nuclear speckles. Relocation of the EDC locus occurs prior to the full activation of EDC genes involved in controlling terminal keratinocyte differentiation and is a lineage-specific, developmentally regulated event controlled by transcription factor p63, a master regulator of epidermal development. We also show that, in epidermal progenitor cells, p63 directly regulates the expression of the ATP-dependent chromatin remodeller Brg1, which binds to distinct domains within the EDC and is required for relocation of the EDC towards the nuclear interior. Furthermore, Brg1 also regulates gene expression within the EDC locus during epidermal morphogenesis. Thus, p63 and its direct target Brg1 play an essential role in remodelling the higher-order chromatin structure of the EDC and in the specific positioning of this locus within the landscape of the 3D nuclear space, as required for the efficient expression of EDC genes in epidermal progenitor cells during skin development. PMID:24346698

  17. Fatal Metastatic Cutaneous Squamous Cell Carcinoma Evolving from a Localized Verrucous Epidermal Nevus

    Directory of Open Access Journals (Sweden)

    Hassan Riad

    2013-10-01

    Full Text Available A malignant transformation is known to occur in many nevi such as a sebaceous nevus or a basal cell nevus, but a verrucous epidermal nevus has only rarely been associated with neoplastic changes. Keratoacanthoma, multifocal papillary apocrine adenoma, multiple malignant eccrine poroma, basal cell carcinoma and cutaneous squamous cell carcinoma (CSCC have all been reported to develop from a verrucous epidermal nevus. CSCC has also been reported to arise from other nevoid lesions like a nevus comedonicus, porokeratosis, a sebaceous nevus, an oral sponge nevus and an ichthyosiform nevus with CHILD syndrome. Here we report a case of progressive poorly differentiated CSCC arising from a localized verrucous epidermal nevus, which caused both spinal cord and brain metastasis.

  18. A stem cell proliferation burst forms new layers of P63 expressing suprabasal cells during zebrafish postembryonic epidermal development

    Directory of Open Access Journals (Sweden)

    Aida Guzman

    2013-09-01

    Organ growth during development is a highly regulated process with both temporal and spatial constraints. Epidermal stratification is essential for skin growth and development. Although the zebrafish has been well studied, it is not known when and how epidermal stratification occurs. This is because beyond the first five days of development our knowledge is currently limited. We found that epidermal stratification in zebrafish begins when the larvae reach a standard length (SL of 6 mm at approximately 25 days of age. Over the next four days (from a SL of 6 to 9 mm, epidermis thickness increases almost four-fold. This represents a sudden increase in organ size, since for the previous 20 days of development, the epidermis has been only two layers thick. This pattern is different from that observed in mammals that undergo continuous stratification from E14.5–E18.5. To study how stem cell proliferation gives rise to the new epidermal layers, we used a combination of markers: one for cell proliferation (proliferating cell nuclear-antigen PCNA and one for epidermal stem cells (P63 transcription factor. We identified, throughout the stratification process, two different waves of cell division. Initially, the most basal epidermal cells divided and generated a subset of suprabasal cells (possibly transient-amplifying cells; within the next several days, the basal cells stopped dividing, and the suprabasal cells began proliferation, giving rise to most of the cell types in the new layers. This part of the process is similar to what has been recently found during epidermal stratification in mammals.

  19. [Effects of transfection of human epidermal growth factor gene with adenovirus vector on biological characteristics of human epidermal cells].

    Science.gov (United States)

    Yin, Kai; Ma, Li; Shen, Chuan'an; Shang, Yuru; Li, Dawei; Li, Longzhu; Zhao, Dongxu; Cheng, Wenfeng

    2016-05-01

    To investigate the suitable transfection condition of human epidermal cells (hECs) with human epidermal growth factor (EGF) gene by adenovirus vector (Ad-hEGF) and its effects on the biological characteristics of hECs. hECs were isolated from deprecated human fresh prepuce tissue of circumcision by enzyme digestion method and then sub-cultured. hECs of the third passage were used in the following experiments. (1) Cells were divided into non-transfection group and 5, 20, 50, 100, 150, and 200 fold transfection groups according to the random number table (the same grouping method below), with 3 wells in each group. Cells in non-transfection group were not transfected with Ad-hEGF gene, while cells in the latter six groups were transfected with Ad-hEGF gene in multiplicities of infection (MOI) of 5, 20, 50, 100, 150, and 200 respectively. The morphology of the cells was observed with inverted phase contrast microscope, and expression of green fluorescent protein of the cells was observed with inverted fluorescence microscope at transfection hour (TH) 24, 48, and 72. (2) Another three batches of cells were collected, grouped, and treated as above, respectively. Then the transfection rate of Ad-hEGF gene was detected by flow cytometer (n=3), the mass concentration of EGF in culture supernatant of cells was detected by enzyme-linked immunosorbent assay (n=6), and the proliferation activity of cells was detected by cell counting kit 8 (CCK8) and microplate reader (n=6) at TH 24, 48, and 72, respectively. (3) Cells were collected and divided into non-transfection group and transfection group, with 6 wells in each group. Cells in non-transfection group were cultured with culture supernatant of cells without transfection, while cells in transfection group were cultured with culture supernatant of cells which were transfected with Ad-hEGF gene in the optimum MOI (50). CCK8 and microplate reader were used to measure the biological activity of EGF secreted by cells on culture

  20. Interfollicular epidermal stem cells self-renew via autocrine Wnt signaling.

    Science.gov (United States)

    Lim, Xinhong; Tan, Si Hui; Koh, Winston Lian Chye; Chau, Rosanna Man Wah; Yan, Kelley S; Kuo, Calvin J; van Amerongen, Renée; Klein, Allon Moshe; Nusse, Roel

    2013-12-06

    The skin is a classical example of a tissue maintained by stem cells. However, the identity of the stem cells that maintain the interfollicular epidermis and the source of the signals that control their activity remain unclear. Using mouse lineage tracing and quantitative clonal analyses, we showed that the Wnt target gene Axin2 marks interfollicular epidermal stem cells. These Axin2-expressing cells constitute the majority of the basal epidermal layer, compete neutrally, and require Wnt/β-catenin signaling to proliferate. The same cells contribute robustly to wound healing, with no requirement for a quiescent stem cell subpopulation. By means of double-labeling RNA in situ hybridization in mice, we showed that the Axin2-expressing cells themselves produce Wnt signals as well as long-range secreted Wnt inhibitors, suggesting an autocrine mechanism of stem cell self-renewal.

  1. Calcium-calmodulin signalling is involved in light-induced acidification by epidermal leaf cells of pea, Pisum sativum L.

    NARCIS (Netherlands)

    Elzenga, JTM; Staal, M; Prins, HBA

    1997-01-01

    Pathways of signal transduction of red and blue light-dependent acidification by leaf epidermal cells were studied using epidermal strips of the Argenteum mutant of Pisum sativum. In these preparations the contribution of guard cells to the acidification is minimal. The hydroxypyridine nifedipine, a

  2. Wdr1-mediated cell shape dynamics and cortical tension are essential for epidermal planar cell polarity.

    Science.gov (United States)

    Luxenburg, Chen; Heller, Evan; Pasolli, H Amalia; Chai, Sophia; Nikolova, Maria; Stokes, Nicole; Fuchs, Elaine

    2015-05-01

    During mouse development, core planar cell polarity (PCP) proteins become polarized in the epidermal plane to guide angling/morphogenesis of hair follicles. How PCP is established is poorly understood. Here, we identify a key role for Wdr1 (also known as Aip1), an F-actin-binding protein that enhances cofilin/destrin-mediated F-actin disassembly. We show that cofilin and destrin function redundantly in developing epidermis, but their combined depletion perturbs cell adhesion, cytokinesis, apicobasal polarity and PCP. Although Wdr1 depletion accentuates single-loss-of-cofilin/destrin phenotypes, alone it resembles core PCP mutations. Seeking a mechanism, we find that Wdr1 and cofilin/destrin-mediated actomyosin remodelling are essential for generating or maintaining cortical tension within the developing epidermal sheet and driving the cell shape and planar orientation changes that accompany establishment of PCP in mammalian epidermis. Our findings suggest intriguing evolutionary parallels but mechanistic modifications to the distal wing hinge-mediated mechanical forces that drive cell shape change and orient PCP in the Drosophila wing disc.

  3. Epidermal cells help coordinate leukocyte migration during inflammation through fatty acid-fuelled matrix metalloproteinase production.

    Science.gov (United States)

    Hall, Christopher J; Boyle, Rachel H; Sun, Xueying; Wicker, Sophie M; Misa, June P; Krissansen, Geoffrey W; Print, Cristin G; Crosier, Kathryn E; Crosier, Philip S

    2014-05-23

    In addition to satisfying the metabolic demands of cells, mitochondrial metabolism helps regulate immune cell function. To date, such cell-intrinsic metabolic-immunologic cross-talk has only been described operating in cells of the immune system. Here we show that epidermal cells utilize fatty acid β-oxidation to fuel their contribution to the immune response during cutaneous inflammation. By live imaging metabolic and immunological processes within intact zebrafish embryos during cutaneous inflammation, we uncover a mechanism where elevated β-oxidation-fuelled mitochondria-derived reactive oxygen species within epidermal cells helps guide matrix metalloproteinase-driven leukocyte recruitment. This mechanism requires the activity of a zebrafish homologue of the mammalian mitochondrial enzyme, Immunoresponsive gene 1. This study describes the first example of metabolic reprogramming operating within a non-immune cell type to help control its contribution to the immune response. Targeting of this metabolic-immunologic interface within keratinocytes may prove useful in treating inflammatory dermatoses.

  4. Human epidermal Langerhans cells express the high affinity receptor for immunoglobulin E (Fc epsilon RI)

    OpenAIRE

    1992-01-01

    It has been suggested that epidermal Langerhans cells (LC) bearing immunoglobulin E (IgE) may be involved in the genesis of atopic disease. The identity of the IgE receptor(s) on LC remained unclear, although it represents a crucial point in understanding cellular events linked to the binding of allergens to LC via IgE. In this report, we demonstrate that epidermal LC express the high affinity receptor for the Fc fragment of IgE (Fc epsilon RI) which has, so far, only been described on mast c...

  5. A Theoretical Model of Jigsaw-Puzzle Pattern Formation by Plant Leaf Epidermal Cells.

    Science.gov (United States)

    Higaki, Takumi; Kutsuna, Natsumaro; Akita, Kae; Takigawa-Imamura, Hisako; Yoshimura, Kenji; Miura, Takashi

    2016-04-01

    Plant leaf epidermal cells exhibit a jigsaw puzzle-like pattern that is generated by interdigitation of the cell wall during leaf development. The contribution of two ROP GTPases, ROP2 and ROP6, to the cytoskeletal dynamics that regulate epidermal cell wall interdigitation has already been examined; however, how interactions between these molecules result in pattern formation remains to be elucidated. Here, we propose a simple interface equation model that incorporates both the cell wall remodeling activity of ROP GTPases and the diffusible signaling molecules by which they are regulated. This model successfully reproduces pattern formation observed in vivo, and explains the counterintuitive experimental results of decreased cellulose production and increased thickness. Our model also reproduces the dynamics of three-way cell wall junctions. Therefore, this model provides a possible mechanism for cell wall interdigitation formation in vivo.

  6. Amplification of epidermal growth factor receptor gene in renal cell carcinoma

    DEFF Research Database (Denmark)

    Harper, Peter; El-Hariry, Iman; Powles, Thomas;

    2010-01-01

    Expression of epidermal growth factor receptor (EGFR) may be of prognostic value in renal cell cancer (RCC). Gene amplification of EGFR was investigated in a cohort of 315 patients with advanced RCC from a previously reported randomised study. Using fluorescent in situ hybridisation, only 2...

  7. Changes in epidermal growth factor receptor expression during chemotherapy in non-small cell lung cancer

    DEFF Research Database (Denmark)

    Jakobsen, Jan Nyrop; Santoni-Rugiu, Eric; Sørensen, Jens Benn

    2014-01-01

    BACKGROUND: Antibodies targeting epidermal growth factor receptor (EGFR), such as cetuximab, may potentially improve outcome in non-small cell lung cancer (NSCLC) patients with high EGFR expression. The EGFR expression may be heterogeneously distributed within tumors, and small biopsies may thus...

  8. Short communication: Initial evidence supporting existence of potential rumen epidermal stem and progenitor cells.

    Science.gov (United States)

    Yohe, T T; Tucker, H L M; Parsons, C L M; Geiger, A J; Akers, R M; Daniels, K M

    2016-09-01

    The bovine rumen epidermis is a keratinized multilayered tissue that experiences persistent cell turnover. Because of this constant cell turnover, epidermal stem cells and their slightly more differentiated daughter cells, epidermal progenitor cells, must exist in the stratum basale of rumen epidermis. To date, these 2 epidermal cell populations and any unique cellular markers they may possess remain completely uncharacterized in the bovine rumen. An important first step in this new research area is the demonstration of the relative abundance and existence of markers for these cells in rumen tissue. A related second step is to document rumen epidermal proliferative responses to an extrinsic signal such as nutrient concentration within the rumen. The objectives of this experiment were to evaluate the extrinsic effect of diet on (1) gene expression of 6 potential rumen epidermal stem or progenitor cell markers and (2) rumen epidermal cell proliferation within the stratum basale. Twelve preweaned Holstein heifers were fed either a restricted diet (R) or an enhanced diet (EH). Animals on R received a milk replacer (MR) diet fed at 0.44kg of powder dry matter (DM)/d (20.9% crude protein, 29.8% fat, DM basis) and EH received MR at 1.08kg of powder dry matter/d (28.9% crude protein, 26.2% fat, DM basis). All calves had access to a 20% crude protein starter and were weaned during wk 7 of the experiment. Lifetime DM intake was 0.73kg of DM/calf per day for R (5.88 Mcal of net energy/calf per day) and 1.26kg of DM/calf per day for EH (10.68 Mcal of net energy/calf per day). Twenty-four hours before slaughter heifers received an intravenous dose of 5-bromo-2'-deoxyuridine to label proliferating cells. Heifers were slaughtered at 8 wk of age, and rumen samples from the ventral sac region were obtained and stored in RNA preservative and processed for routine histology. Quantitative real-time reverse transcriptase PCR was used to analyze relative abundance of genes. Candidate

  9. The effect of ruby laser light on cellular proliferation of epidermal cells.

    Science.gov (United States)

    Liew, S H; Grobbelaar, A O; Gault, D T; Green, C J; Linge, C

    1999-11-01

    In ruby laser-assisted hair removal, microscopic damage is often seen in the basal epidermal cells, where melanosomes are concentrated. It is not known whether this treatment leads to cellular hyperproliferation. It was the aim of this study to investigate this. Ten white patients were treated with the Chromos 694-nm Depilation Ruby Laser, and biopsies taken before and after treatments to assess the presence of cell hyperproliferation, which normally accompanies epidermal damage, with immunohistochemical staining of keratin 16 and Ki67. No evidence of cell hyperproliferation was seen in all specimens examined after ruby laser irradiation. The authors conclude that despite the possible microscopic damages seen in the basal epidermis after laser hair removal, there is no evidence of cellular hyperproliferation. This is in contrast to ultraviolet-irradiated cell damage, in which increased basal cell turnover is seen.

  10. Epidermal Cells Expressing Putative Cell Markers in Nonglabrous Skin Existing in Direct Proximity with the Distal End of the Arrector Pili Muscle

    Directory of Open Access Journals (Sweden)

    N. Torkamani

    2016-01-01

    Full Text Available Inconsistent with the view that epidermal stem cells reside randomly spread along the basal layer of the epidermal rete ridges, we found that epidermal cells expressing stem cell markers in nonglabrous skin exist in direct connection with the distal end of the arrector pili muscle. The epidermal cells that express stem cell markers consist of a subpopulation of basal keratinocytes located in a niche at the lowermost portion of the rete ridges at the distal arrector pili muscle attachment site. Keratinocytes in the epidermal stem cell niche express K15, MCSP, and α6 integrin. α5 integrin marks the distal end of the APM colocalized with basal keratinocytes expressing stem cell markers located in a well-protected and nourished environment at the lowermost point of the epidermis; these cells are hypothesized to participate directly in epidermal renewal and homeostasis and also indirectly in wound healing through communication with the hair follicle bulge epithelial stem cell population through the APM. Our findings, plus a reevaluation of the literature, support the hierarchical model of interfollicular epidermal stem cell units of Fitzpatrick. This new view provides insights into epidermal control and the possible involvement of epidermal stem cells in nonmelanoma skin carcinogenesis.

  11. Single cell-type comparative metabolomics of epidermal bladder cells from the halophyte Mesembryanthemum crystallinum.

    Directory of Open Access Journals (Sweden)

    Bronwyn Jane Barkla

    2015-06-01

    Full Text Available One of the remarkable adaptive features of the halophyte and facultative CAM plant Mesembryathemum crystallinum are the specialized modified trichomes called epidermal bladder cells (EBC which cover the leaves, stems, and peduncle of the plant. They are present from an early developmental stage but upon salt stress rapidly expand due to the accumulation of water and sodium. This particular plant feature makes it an attractive system for single cell type studies, with recent proteomics and transcriptomics studies of the EBC establishing that these cells are metabolically active and have roles other than sodium sequestration. To continue our investigation into the function of these unusual cells we carried out a comprehensive global analysis of the metabolites present in the EBC extract by gas chromatography Time-of-Flight mass spectrometry (GC-TOF and identified 194 known and 722 total molecular features. Statistical analysis of the metabolic changes between control and salt-treated samples was used to identify 352 significantly differing metabolites (268 after correction for FDR. Principal components analysis provided an unbiased evaluation of the data variance structure. Biochemical pathway enrichment analysis suggested significant perturbations in 13 biochemical pathways as defined in KEGG. More than 50% of the metabolites that show significant changes in the EBC, can be classified as compatible solutes and include sugars, sugar alcohols, protein and non-protein amino acids, and organic acids, highlighting the need to maintain osmotic homeostasis to balance the accumulation of Na and Cl ions. Overall, the comparison of metabolic changes in salt treated relative to control samples suggest large alterations in Mesembryanthemum crystallinum epidermal bladder cells.

  12. Neuropilin 1 expression correlates with differentiation status of epidermal cells and cutaneous squamous cell carcinomas.

    Science.gov (United States)

    Shahrabi-Farahani, Shokoufeh; Wang, Lili; Zwaans, Bernadette M M; Santana, Jeans M; Shimizu, Akio; Takashima, Seiji; Kreuter, Michael; Coultas, Leigh; D'Amore, Patricia A; Arbeit, Jeffrey M; Akslen, Lars A; Bielenberg, Diane R

    2014-07-01

    Neuropilins (NRPs) are cell surface receptors for vascular endothelial growth factor (VEGF) and SEMA3 (class 3 semaphorin) family members. The role of NRPs in neurons and endothelial cells has been investigated, but the expression and role of NRPs in epithelial cells is much less clear. Herein, the expression and localization of NRP1 was investigated in human and mouse skin and squamous cell carcinomas (SCCs). Results indicated that NRP1 mRNA and protein was expressed in the suprabasal epithelial layers of the skin sections. NRP1 staining did not overlap with that of keratin 14 (K14) or proliferating cell nuclear antigen, but did co-localize with staining for keratin 1, indicating that differentiated keratinocytes express NRP1. Similar to the expression of NRP1, VEGF-A was expressed in suprabasal epithelial cells, whereas Nrp2 and VEGFR2 were not detectable in the epidermis. The expression of NRP1 correlated with a high degree of differentiation in human SCC specimens, human SCC xenografts, and mouse K14-HPV16 transgenic SCC. UVB irradiation of mouse skin induced Nrp1 upregulation. In vitro, Nrp1 was upregulated in primary keratinocytes in response to differentiating media or epidermal growth factor-family growth factors. In conclusion, the expression of NRP1 is regulated in the skin and is selectively produced in differentiated epithelial cells. NRP1 may function as a reservoir to sequester VEGF ligand within the epithelial compartment, thereby modulating its bioactivity.

  13. Expression of the epidermal growth factor receptor in human small cell lung cancer cell lines

    DEFF Research Database (Denmark)

    Damstrup, L; Rygaard, K; Spang-Thomsen, M;

    1992-01-01

    Epidermal growth factor (EGF) receptor expression was evaluated in a panel of 21 small cell lung cancer cell lines with radioreceptor assay, affinity labeling, and Northern blotting. We found high-affinity receptors to be expressed in 10 cell lines. Scatchard analysis of the binding data...... demonstrated that the cells bound between 3 and 52 fmol/mg protein with a KD ranging from 0.5 x 10(-10) to 2.7 x 10(-10) M. EGF binding to the receptor was confirmed by affinity-labeling EGF to the EGF receptor. The cross-linked complex had a M(r) of 170,000-180,000. Northern blotting showed the expression...... of EGF receptor mRNA in all 10 cell lines that were found to be EGF receptor-positive and in one cell line that was found to be EGF receptor-negative in the radioreceptor assay and affinity labeling. Our results provide, for the first time, evidence that a large proportion of a broad panel of small cell...

  14. Pro-MMP-9 upregulation in HT1080 cells expressing CD9 is regulated by epidermal growth factor receptor.

    Science.gov (United States)

    Herr, Michael J; Mabry, Scott E; Jameson, Jessica F; Jennings, Lisa K

    2013-12-06

    Degradation of the surrounding extracellular matrix (ECM) by matrix metalloproteinases (MMPs) drives invasion and metastasis of cancer cells. We previously demonstrated that tetraspanin CD9 expression upregulates pro-MMP-9 expression and release and promotes cellular invasion in a human fibrosarcoma cell line (HT1080). These events were dependent upon the highly functional second extracellular loop of CD9. We report here that the epidermal growth factor receptor (EGFR) tyrosine kinase expression and activity are involved in the CD9-mediated increase in pro-MMP-9 release and cellular invasion. Pro-MMP-9 expression was significantly decreased in a dose-dependent manner using first a broad spectrum receptor tyrosine kinase inhibitor and multiple specific EGFR inhibitors in CD9-HT1080 cells. Furthermore, gefitinib treatment of CD9-HT1080 cells reduced invasion through matrigel. EGFR knockdown using short interfering RNA resulted in decreased pro-MMP-9 expression and release into the media and subsequent cellular invasion without affecting CD9 expression or localization. Conclusively, this study points to EGFR as a key mediator between CD9-mediated pro-MMP-9 release and cellular invasion of HT1080 cells. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Cell fate determination in the Caenorhabditis elegans epidermal lineages

    NARCIS (Netherlands)

    Soete, G.A.J.

    2007-01-01

    The starting point for this work was to use the hypodermal seam of C. elegans as a model system to study cell fate determination. Even though the seam is a relatively simple developmental system, the mechanisms that control cell fate determination in the seam lineages are connected in a highly compl

  16. Cell fate determination in the Caenorhabditis elegans epidermal lineages

    NARCIS (Netherlands)

    Soete, G.A.J.

    2007-01-01

    The starting point for this work was to use the hypodermal seam of C. elegans as a model system to study cell fate determination. Even though the seam is a relatively simple developmental system, the mechanisms that control cell fate determination in the seam lineages are connected in a highly compl

  17. Isolation and In Vitro Characterization of Epidermal Stem Cells

    DEFF Research Database (Denmark)

    Moestrup, Kasper S; Andersen, Marianne Stemann; Jensen, Kim Bak

    2017-01-01

    Colony-forming assays represent prospective methods, where cells isolated from enzymatically dissociated tissues or from tissue cultures are assessed for their proliferative capacity in vitro. Complex tissues such as the epithelial component of the skin (the epidermis) are characterized by a subs...... skin sorted by surface antigens associated with adult stem cell characteristics.......Colony-forming assays represent prospective methods, where cells isolated from enzymatically dissociated tissues or from tissue cultures are assessed for their proliferative capacity in vitro. Complex tissues such as the epithelial component of the skin (the epidermis) are characterized...... by a substantial cellular heterogeneity. Analysis of bulk populations of cells by colony-forming assays can consequently be convoluted by a number of factors that are not controlled for in population wide studies. It is therefore advantageous to refine in vitro growth assays by sub-fractionation of cells using...

  18. Optimal Therapeutic Strategy for Non-small Cell Lung Cancer with Mutated Epidermal Growth Factor Receptor

    Directory of Open Access Journals (Sweden)

    Zhong SHI

    2015-02-01

    Full Text Available Although epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs have been widely used in non-small cell lung cancer (NSCLC patients, it is still controversial about how to combine EGFR-TKI with chemotherapy and other targeted drugs. We have made a summary on the current therapeutic models of EGFR-TKI combined with chemotherapy/bevacizumab in this review and aimed to find the optimal therapeutic strategy for NSCLC patients with EGFR mutation.

  19. Outcome of burns treated with autologous cultured proliferating epidermal cells: a prospective randomized multicenter intrapatient comparative trial

    NARCIS (Netherlands)

    Gardien, K.L.M.; Marck, R.E.; Bloemen, M.C.T.; Waaijman, T.; Gibbs, S.; Uhlrich, M.M.W.; Middelkoop, E.

    2016-01-01

    Standard treatment for large burns is transplantation with meshed split skin autografts (SSGs). A disadvantage of this treatment is that healing is accompanied by scar formation. Application of autologous epidermal cells (keratinocytes and melanocytes) may be a suitable therapeutic alternative,

  20. Substance P combined with epidermal stem cells promotes wound healing and nerve regeneration in diabetes mellitus

    Institute of Scientific and Technical Information of China (English)

    Fei-bin Zhu; Xiang-jing Fang; De-wu Liu; Ying Shao; Hong-yan Zhang; Yan Peng; Qing-ling Zhong; Yong-tie Li; De-ming Liu

    2016-01-01

    Exogenous substance P accelerates wound healing in diabetes, but the mechanism remains poorly understood. Here, we established a rat model by intraperitoneally injecting streptozotocin. Four wounds (1.8 cm diameter) were drilled using a self-made punch onto the back, bilateral to the vertebral column, and then treated using amniotic membrane with epidermal stem cells and/or substance P around and in the middle of the wounds. With the combined treatment the wound-healing rate was 100% at 14 days. With prolonged time, type I col-lagen content gradually increased, yet type III collagen content gradually diminished. Abundant protein gene product 9.5- and substance P-immunoreactive nerve ifbers regenerated. Partial nerve ifber endings extended to the epidermis. The therapeutic effects of combined substance P and epidermal stem cells were better than with amniotic membrane and either factor alone. Our results suggest that the com-bination of substance P and epidermal stem cells effectively contributes to nerve regeneration and wound healing in diabetic rats.

  1. Epidermal stem cells and skin tissue engineering in hairfollicle regeneration

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    The reconstitution of a fully organized and functionalhair follicle from dissociated cells propagated underdefined tissue culture conditions is a challenge stillpending in tissue engineering. The loss of hair folliclescaused by injuries or pathologies such as alopecia notonly affects the patients' psychological well-being, butalso endangers certain inherent functions of the skin. Itis then of great interest to find different strategies aimingto regenerate or neogenerate the hair follicle underconditions proper of an adult individual. Based uponcurrent knowledge on the epithelial and dermal cells andtheir interactions during the embryonic hair generationand adult hair cycling, many researchers have tried toobtain mature hair follicles using different strategies andapproaches depending on the causes of hair loss. Thisreview summarizes current advances in the differentexperimental strategies to regenerate or neogenerate hairfollicles, with emphasis on those involving neogenesisof hair follicles in adult individuals using isolated cellsand tissue engineering. Most of these experiments wereperformed using rodent cells, particularly from embryonicor newborn origin. However, no successful strategy togenerate human hair follicles from adult cells has yetbeen reported. This review identifies several issues thatshould be considered to achieve this objective. Perhapsthe most important challenge is to provide threedimensionalculture conditionsmimicking the structure ofliving tissue. Improving culture conditions that allow theexpansion of specific cells while protecting their inductiveproperties, as well as methods for selecting populationsof epithelial stem cells, should give us the necessary toolsto overcome the difficulties that constrain human hairfollicle neogenesis. An analysis of patent trends showsthat the number of patent applications aimed at hairfollicle regeneration and neogenesis has been increasingduring the last decade. This field is attractive not only

  2. Th22 cells represent a distinct human T cell subset involved in epidermal immunity and remodeling.

    Science.gov (United States)

    Eyerich, Stefanie; Eyerich, Kilian; Pennino, Davide; Carbone, Teresa; Nasorri, Francesca; Pallotta, Sabatino; Cianfarani, Francesca; Odorisio, Teresa; Traidl-Hoffmann, Claudia; Behrendt, Heidrun; Durham, Stephen R; Schmidt-Weber, Carsten B; Cavani, Andrea

    2009-12-01

    Th subsets are defined according to their production of lineage-indicating cytokines and functions. In this study, we have identified a subset of human Th cells that infiltrates the epidermis in individuals with inflammatory skin disorders and is characterized by the secretion of IL-22 and TNF-alpha, but not IFN-gamma, IL-4, or IL-17. In analogy to the Th17 subset, cells with this cytokine profile have been named the Th22 subset. Th22 clones derived from patients with psoriasis were stable in culture and exhibited a transcriptome profile clearly separate from those of Th1, Th2, and Th17 cells; it included genes encoding proteins involved in tissue remodeling, such as FGFs, and chemokines involved in angiogenesis and fibrosis. Primary human keratinocytes exposed to Th22 supernatants expressed a transcriptome response profile that included genes involved in innate immune pathways and the induction and modulation of adaptive immunity. These proinflammatory Th22 responses were synergistically dependent on IL-22 and TNF-alpha. Furthermore, Th22 supernatants enhanced wound healing in an in vitro injury model, which was exclusively dependent on IL-22. In conclusion, the human Th22 subset may represent a separate T cell subset with a distinct identity with respect to gene expression and function, present within the epidermal layer in inflammatory skin diseases. Future strategies directed against the Th22 subset may be of value in chronic inflammatory skin disorders.

  3. Transient expression of P-type ATPases in tobacco epidermal cells

    DEFF Research Database (Denmark)

    Pedas, Lisbeth Rosager; Palmgren, Michael Broberg; Lopez Marques, Rosa Laura

    2016-01-01

    Transient expression in tobacco cells is a convenient method for several purposes such as analysis of protein-protein interactions and the subcellular localization of plant proteins. A suspension of Agrobacterium tumefaciens cells carrying the plasmid of interest is injected into the intracellular...... for example protein-protein interaction studies. In this chapter, we describe the procedure to transiently express P-type ATPases in tobacco epidermal cells, with focus on subcellular localization of the protein complexes formed by P4-ATPases and their β-subunits....

  4. Correlation between Grade in Transitional Cell Carcinoma (TCC and Expression of Epidermal Growth Factor Receptor (EGFR

    Directory of Open Access Journals (Sweden)

    MR Jallali Nadoushan

    2007-08-01

    Full Text Available Background: The present study was undertaken to investigate the correlation of Epidermal Growth Factor Receptor (EGFR expression with grade of Transitional Cell Carcinoma (TCC. Methods: Tumor samples of 75 patients from Mostafa Khomaini Hospital with Transitional Cell Carcinoma of the bladder were analyzed by immunohistochemistry for expression of EGFR. In this context, we assigned the bladder tumors a grade accord¬ing WHO classification. Results analyzed for possible correlation with the expression status of the Epidermal Growth Factor Receptor (EGFR. Results: This cross-sectional study showed that all grades of Transitional Cell Carcinoma expressed EGFR, and 14 cases were LMP (18.9% which 10 cases among them had negative cells according EGFR point of view(71.4% and 4 cases had re¬ported positive (28.6%. Thirty five cases were low grade (46.7% which 18 cases among them had reported negative cells (51.4% and 17 cases had positive cells (48.6%. Twenty six cases were high grade (34.7% that 9 cases among them had reported negative cells (34.6%. Seventeen cases had positive cells (65.4%. Mann-Witney test showed relation between grade and expression of EGFR (P<0.05. Conclusions: This study showed that expression of EGFR is correlated with grade of tumor.

  5. Model system for plant cell biology: GFP imaging in living onion epidermal cells

    Science.gov (United States)

    Scott, A.; Wyatt, S.; Tsou, P. L.; Robertson, D.; Allen, N. S.

    1999-01-01

    The ability to visualize organelle localization and dynamics is very useful in studying cellular physiological events. Until recently, this has been accomplished using a variety of staining methods. However, staining can give inaccurate information due to nonspecific staining, diffusion of the stain or through toxic effects. The ability to target green fluorescent protein (GFP) to various organelles allows for specific labeling of organelles in vivo. The disadvantages of GFP thus far have been the time and money involved in developing stable transformants or maintaining cell cultures for transient expression. In this paper, we present a rapid transient expression system using onion epidermal peels. We have localized GFP to various cellular compartments (including the cell wall) to illustrate the utility of this method and to visualize dynamics of these compartments. The onion epidermis has large, living, transparent cells in a monolayer, making them ideal for visualizing GFP. This method is easy and inexpensive, and it allows for testing of new GFP fusion proteins in a living tissue to determine deleterious effects and the ability to express before stable transformants are attempted.

  6. Model system for plant cell biology: GFP imaging in living onion epidermal cells

    Science.gov (United States)

    Scott, A.; Wyatt, S.; Tsou, P. L.; Robertson, D.; Allen, N. S.

    1999-01-01

    The ability to visualize organelle localization and dynamics is very useful in studying cellular physiological events. Until recently, this has been accomplished using a variety of staining methods. However, staining can give inaccurate information due to nonspecific staining, diffusion of the stain or through toxic effects. The ability to target green fluorescent protein (GFP) to various organelles allows for specific labeling of organelles in vivo. The disadvantages of GFP thus far have been the time and money involved in developing stable transformants or maintaining cell cultures for transient expression. In this paper, we present a rapid transient expression system using onion epidermal peels. We have localized GFP to various cellular compartments (including the cell wall) to illustrate the utility of this method and to visualize dynamics of these compartments. The onion epidermis has large, living, transparent cells in a monolayer, making them ideal for visualizing GFP. This method is easy and inexpensive, and it allows for testing of new GFP fusion proteins in a living tissue to determine deleterious effects and the ability to express before stable transformants are attempted.

  7. Relationship between the number of cells surrounding oocytes and energy states of oocytes.

    Science.gov (United States)

    Munakata, Yasuhisa; Ichinose, Tomoya; Ogawa, Kaori; Itami, Nobuhiko; Tasaki, Hidetaka; Shirasuna, Koumei; Kuwayama, Takehito; Iwata, Hisataka

    2016-10-15

    Lipid content, ATP content, and histone acetylation are thought to reflect the energy state of cells. In addition, the energy state closely associates with growth and developmental ability of oocytes. Oocyte growth is accompanied by active proliferation of the surrounding granulosa cells (GCs), and GCs play a key role in the provision of energy substrates to the oocytes. In the present study, we first examined the relationship among the average number of GCs per follicle, the average number of cumulus cells (CCs) per oocyte, and the average lipid content in oocytes that developed in vivo within individual donor gilts. Second, we validated the relationship between the number of cells surrounding oocytes and the energy states of oocytes by using an IVC system of oocyte granulosa cell complexes (OGCs) derived from early antral follicles. We collected cumulus cells and oocyte complexes (COCs) from antral follicles (3-5 mm in diameter) and found that average lipid content in oocytes significantly correlated with the average number of both GCs/follicle and CCs/oocyte (P cell number of OGCs, as well as the lipid content, ATP content, and acetylation level of H4K12 in oocytes grown in vitro. In addition, glucose consumption by OGCs was calculated from the sample media collected at Days 13 and 14. The lipid content of oocytes grown in vitro, significantly correlated with the number of cells surrounding the oocytes (P number of cells surrounding the oocytes (P number of cells surrounding the oocytes, and glucose uptake by OGCs is crucial for lipid content and ATP content, and H4K12 acetylation in oocytes.

  8. Enrichment of putative human epidermal stem cells based on cell size and collagen type IV adhesiveness

    Institute of Scientific and Technical Information of China (English)

    Juxue Li; Enkui Duan; Chenglin Miao; Weixiang Guo; Liwei Jia; Jiaxi Zhou; Baohua Ma; Sha Peng; Shuang Liu; Yujing Cao

    2008-01-01

    The enrichment and identification of human epidermal stem cells (EpSCs) are of paramount importance for both basic research and clinical application. Although several approaches for the enrichment of EpSCs have been established, enriching a pure population of viable EpSCs is still a challenging task. An improved approach is worth developing to enhance the purity and viability of EpSCs. Here we report that cell size combined with collagen type IV adhesiveness can be used in an improved approach to enrich pure and viable human EpSCs. We separated the rapidly adherent keratinocytes into three populations that range in size from 5-7 μm (population A), to 7-9 μm (population B), to >9 μm (population C) in diameter, and found that human putative EpSCs could be further enriched in population A with the smallest size. Among the three populations, population A displayed the highest density of βl-integrin receptor, contained the highest percentage of cells in G0/G1 phase, showed the highest nucleus to cytoplasm ratio, and possessed the highest colony formation efficiency (CFE). When injected into murine blastocysts, these cells participated in multi-tissue formation. More significantly, compared with a previous approach that sorted putative EpSCs according to pl-integrin antibody staining, the viability of the EpSCs enriched by the improved approach was significantly enhanced. Our results provide a putative strategy for the enrichment of human EpSCs, and encourage further study into the role of cell size in stem cell biology.

  9. Communication is key: Reducing DEK1 activity reveals a link between cell-cell contacts and epidermal cell differentiation status.

    Science.gov (United States)

    Galletti, Roberta; Ingram, Gwyneth C

    2015-01-01

    Plant epidermis development requires not only the initial acquisition of tissue identity, but also the ability to differentiate specific cell types over time and to maintain these differentiated states throughout the plant life. To set-up and maintain differentiation, plants activate specific transcriptional programs. Interfering with these programs can prevent differentiation and/or force differentiated cells to lose their identity and re-enter a proliferative state. We have recently shown that the Arabidopsis Defective Kernel 1 (DEK1) protein is required both for the differentiation of epidermal cells and for the maintenance of their fully differentiated state. Defects in DEK1 activity lead to a deregulation of the expression of epidermis-specific differentiation-promoting HD-ZIP IV transcription factors. Here we propose a working model in which DEK1, by maintaining cell-cell contacts, and thus communication between neighboring cells, influences HD-ZIP IV gene expression and epidermis differentiation.

  10. Expression of an Exogenous Growth Hormone Gene by Transplantable Human Epidermal Cells

    Science.gov (United States)

    Morgan, Jeffrey R.; Barrandon, Yann; Green, Howard; Mulligan, Richard C.

    1987-09-01

    Retrovirus-mediated gene transfer was used to introduce a recombinant human growth hormone gene into cultured human keratinocytes. The transduced keratinocytes secreted biologically active growth hormone into the culture medium. When grafted as an epithelial sheet onto athymic mice, these cultured keratinocytes reconstituted an epidermis that was similar in appearance to that resulting from normal cells, but from which human growth hormone could be extracted. Transduced epidermal cells may prove to be a general vehicle for the delivery of gene products by means of grafting.

  11. Colchicine inhibits epidermal growth factor degradation in 3T3 cells.

    OpenAIRE

    Brown, K. D.; Friedkin, M; Rozengurt, E

    1980-01-01

    Colchicine (2 microM) did not affect the initial rate of association of 125I-labeled epidermal growth factor (125I-EGF) to Swiss 3T3 cells but continued incubation (up to 24 hr) led to an increase in cell-associated radioactivity. The effect is also produced by Colcemid, vinblastine, and podophyllotoxin but not by lumicolchicine. Disruption of microtubules with colchicine does not alter the rate of "down regulation" of EGF receptors, suggesting the binding and internalization of the factor pr...

  12. Electric fields guide migration of epidermal stem cells and promote skin wound healing.

    Science.gov (United States)

    Li, Li; Gu, Wei; Du, Juan; Reid, Brian; Deng, Xianjian; Liu, Zhidai; Zong, Zhaowen; Wang, Haiyan; Yao, Bo; Yang, Ce; Yan, Jun; Zeng, Ling; Chalmers, Laura; Zhao, Min; Jiang, Jianxin

    2012-01-01

    Migration of epidermal stem cells (EpSCs) into wounds may play an important role in wound healing. Endogenous electric fields (EFs) arise naturally at wounds. Consistent with previous reports, we measured outward electric currents at rat skin wounds using vibrating probes. Topical use of prostaglandin E2 significantly promoted wound healing. However, it is not known whether EpSCs respond to EFs. We first isolated and characterized EpSCs from rat skin. We then demonstrated that EpSCs isolated from the epidermis migrated directionally toward the cathode in EFs of 50-400 mV/mm. The directedness values increased in a dose- and time-dependent fashion. The migration speed of EpSCs was significantly increased in EFs. EFs induced asymmetric polymerization of intracellular F-actin and activation of the extracellular signal-regulated kinase 1/2 and phosphatidylinositol-3-kinase (PI3K)/protein kinase B pathways. Inhibition of epidermal growth factor receptor, extracellular signal-regulated kinase 1/2, or PI3K significantly inhibited the cathodal distribution of F-actin and the electrotactic response of EpSCs. These data for the first time show that EpSCs possess obvious electrotaxis, in which the epidermal growth factor receptor-mitogen activated protein kinase-PI3K pathways are involved. These data thus suggest a novel aspect of electric signaling in wound healing-to stimulate and guide migration of EpSCs and to regulate wound healing.

  13. EXPRESSION OF EPIDERMAL GROWTH FACTOR RECEPTOR IN DIFFERENT SALIVARY ADENOID CYSTIC CARCINOMA CELL LINES

    Institute of Scientific and Technical Information of China (English)

    MA Jie; ZONG Zhi-hong; WANG Zhao-yuan

    2005-01-01

    Objective: To investigate the expression of epidermal growth factor receptor, a receptor tyrosine protein kinase, in the subcellular fractions of human salivary adenoid cystic carcinoma cell lines SACC-83 and SACC-LM. Methods: Low metastatic and high metastatic cells of the adenoid cystic carcinoma, SACC-83 and SACC-LM, were cultured. Their subcellular fractions were extracted. The expression of epidermal growth factor receptor was detected with Western blot method, and the results of protein expression were quantitatively analyzed by FluorChem V2.0 software. Results: The results of Western blot analysis indicated that, EGFR expression on the membrane of SACC-83 cells was significantly higher than that of SACC-LM cells, but its expression in cytoplasm was significantly less in the former than the later (P<0.01). In SACC-83 cell line, EGFR was over-expressed in membrane (P<0.01), but in SACC-LM cell line, EGFR was over-expressed in cytoplasm (P<0.01). Conclusion: The results suggest that the obtaining of metastasis ability is related to the high expression of EGFR protein in cytoplasm, so the molecular targeting therapy to EGFR may be an ideal treatment for the invasion and metastasis of salivary adenoid cystic carcinoma.

  14. A sensitive electrochemiluminescence cytosensor for quantitative evaluation of epidermal growth factor receptor expressed on cell surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Yanjuan; Zhang, Shaolian; Wen, Qingqing; Huang, Hongxing; Yang, Peihui, E-mail: typh@jnu.edu.cn

    2015-06-30

    Highlights: • EGF-cytosensor was used for evaluating EGFR expression level on cell surfaces. • CdSQDs and EGF were coated on magnetic beads (MBs) for ECL-probe. • Good sensitivity was achieved due to the signal amplification of ECL-probe. - Abstract: A sensitive electrochemiluminescence (ECL) strategy for evaluating the epidermal growth factor receptor (EGFR) expression level on cell surfaces was designed by integrating the specific recognition of EGFR expressed on MCF-7 cell surfaces with an epidermal growth factor (EGF)-funtionalized CdS quantum dots (CdSQDs)-capped magnetic bead (MB) probe. The high sensitivity of ECL probe of EGF-funtionalized CdSQD-capped-MB was used for competitive recognition with EGFR expressed on cell surfaces with recombinant EGFR protein. The changes of ECL intensity depended on both the cell number and the expression level of EGFR receptor on cell surfaces. A wide linear response to cells ranging from 80 to 4 × 10{sup 6} cells mL{sup −1} with a detection limit of 40 cells mL{sup −1} was obtained. The EGF-cytosensor was used to evaluate EGFR expression levels on MCF-7 cells, and the average number of EGFR receptor on single MCF-7 cells was 1.35 × 10{sup 5} with the relative standard deviation of 4.3%. This strategy was further used for in-situ and real-time evaluating EGFR receptor expressed on cell surfaces in response to drugs stimulation at different concentration and incubation time. The proposed method provided potential applications in the detection of receptors on cancer cells and anticancer drugs screening.

  15. Whole organ, venation and epidermal cell morphological variations are correlated in the leaves of Arabidopsis mutants.

    Science.gov (United States)

    Pérez-Pérez, José Manuel; Rubio-Díaz, Silvia; Dhondt, Stijn; Hernández-Romero, Diana; Sánchez-Soriano, Joaquín; Beemster, Gerrit T S; Ponce, María Rosa; Micol, José Luis

    2011-12-01

    Despite the large number of genes known to affect leaf shape or size, we still have a relatively poor understanding of how leaf morphology is established. For example, little is known about how cell division and cell expansion are controlled and coordinated within a growing leaf to eventually develop into a laminar organ of a definite size. To obtain a global perspective of the cellular basis of variations in leaf morphology at the organ, tissue and cell levels, we studied a collection of 111 non-allelic mutants with abnormally shaped and/or sized leaves, which broadly represent the mutational variations in Arabidopsis thaliana leaf morphology not associated with lethality. We used image-processing techniques on these mutants to quantify morphological parameters running the gamut from the palisade mesophyll and epidermal cells to the venation, whole leaf and rosette levels. We found positive correlations between epidermal cell size and leaf area, which is consistent with long-standing Avery's hypothesis that the epidermis drives leaf growth. In addition, venation parameters were positively correlated with leaf area, suggesting that leaf growth and vein patterning share some genetic controls. Positional cloning of the genes affected by the studied mutations will eventually establish functional links between genotypes, molecular functions, cellular parameters and leaf phenotypes.

  16. Epidermal cell differentiation in cotton mediated by the homeodomain leucine zipper gene, GhHD-1.

    Science.gov (United States)

    Walford, Sally-Ann; Wu, Yingru; Llewellyn, Danny J; Dennis, Elizabeth S

    2012-08-01

    Gossypium hirsutum L. (cotton) fibres are specialized trichomes a few centimetres in length that grow from the seed coat. Few genes directly involved in the differentiation of these epidermal cells have been identified. These include GhMYB25-like and GhMYB25, two related MYB transcription factors that regulate fibre cell initiation and expansion. We have also identified a putative homeodomain leucine zipper (HD-ZIP) transcription factor, GhHD-1, expressed in trichomes and early fibres that might play a role in cotton fibre initiation. Here, we characterize GhHD-1 homoeologues from tetraploid G. hirsutum and show, using reporter constructs and quantitative real-time PCR (qRT-PCR), that they are expressed predominantly in epidermal tissues during early fibre development, and in other tissues bearing epidermal trichomes. Silencing of GhHD-1 reduced trichome formation and delayed the timing of fibre initiation. Constitutive overexpression of GhHD-1 increased the number of fibres initiating on the seed, but did not affect leaf trichomes. Expression of GhHD-1 in cotton silenced for different fibre MYBs suggest that in ovules it acts downstream of GhMYB25-like, but is unaffected in GhMYB25- or GhMYB109-silenced plants. Microarray analysis of silencing and overexpression lines of GhHD-1 indicated that it potentially regulates the levels of ethylene and reactive oxidation species (ROS) through a WRKY transcription factor and calcium-signalling pathway genes to activate downstream genes necessary for cell expansion and elongation. © 2012 CSIRO. The Plant Journal © 2012 Blackwell Publishing Ltd.

  17. Presence of Mycobacterium leprae in epidermal cells of lepromatous skin and its significance

    Directory of Open Access Journals (Sweden)

    Satapathy Jasmita

    2005-01-01

    Full Text Available A 49-year-old man with lepromatous leprosy treated with dapsone monotherapy for 12 years (1967 to 1979 reported in the hospital in 2003, with relapsed disease. A slit skin smear showed a bacteriological index of 4+. Biopsies from skin lesions before and after anti-leprosy therapy showed features of lepromatous leprosy. Both biopsies showed unusual features of bacillary clumps in epidermal cells demonstrating clearly that dissemination of M. leprae can take place even through unbroken skin. The presence of lepra bacilli in clumps in the epidermis is an indicator that the skin is a potential route of transmission of the disease.

  18. Immunoreactive transforming growth factor alpha and epidermal growth factor in oral squamous cell carcinomas

    DEFF Research Database (Denmark)

    Therkildsen, M H; Poulsen, Steen Seier; Bretlau, P

    1993-01-01

    , the cells above the basal cell layer were positive for both TGF-alpha and EGF. The same staining pattern was observed in oral mucosa obtained from healthy persons. In moderately to well differentiated carcinomas, the immunoreactivity was mainly confined to the cytologically more differentiated cells, thus......Forty oral squamous cell carcinomas have been investigated immunohistochemically for the presence of transforming growth factor alpha (TGF-alpha) and epidermal growth factor (EGF). The same cases were recently characterized for the expression of EGF-receptors. TGF-alpha was detected...... with a monoclonal mouse antibody and EGF with polyclonal rabbit antiserum. Thirty-five of the tumours were positive for TGF-alpha and 26 of the tumours for EGF. None of the poorly differentiated tumours was positive for EGF, but they all were for TGF-alpha. In sections including normal differentiated oral mucosa...

  19. Role of DNA endoreduplication, lipotubuloids, and gibberellic acid in epidermal cell growth during fruit development of Ornithogalum umbellatum.

    Science.gov (United States)

    Kwiatkowska, Maria; Poplonska, Katarzyna; Kazmierczak, Andrzej; Stepinski, Dariusz; Rogala, Katarzyna; Polewczyk, Katarzyna

    2007-01-01

    Cytophotometry of individual nuclei was used to examine the level of endoreduplication in epidermal cells from the upper and lower parts of the ovary during Ornithogalum umbellatum flower and fruit development. An increase in DNA content from 2-4C to 2-8C in both parts of the ovary was observed, while the epidermal cell surface area grew about 6-fold and 15-fold in the lower and upper parts of the ovary, respectively. However, the correlation between mean epidermal cell size and ploidy was distinct during epidermis growth. Lipotubuloids became bigger in the upper than in the lower part during ovary and fruit development. In addition, more dynamic growth of the epidermal cells of the upper than of the lower part of the ovary was connected to the higher content of gibberellic acid. A hypothesis has been put forward that the role of DNA endoreduplication in epidermal cell growth was modulated by the function of lipotubuloids and the gradient of gibberellin.

  20. RNA interference mediated JAM-A gene silencing promotes human epidermal stem cell proliferation.

    Science.gov (United States)

    Zhou, Tong; Wu, Minjuan; Guo, Xiaocan; Liu, Houqi

    2015-04-01

    The objective of the study was to explore the influence of junctional adhesion molecule A (JAM-A) gene decoration on proliferation and differentiation of human epidermal stem cells (hEpSCs). JAM-A gene and JAM-A interference gene lentivirus eukaryotic expression vectors were established. The recombinant lentivirus was introduced into hEpSCs to observe and detect viral transfection by fluorescence microscopy and Western blot, respectively. After confirmation of successful introduction of the target gene, cell growth curves were mapped out by cytometry to detect cell proliferation in different groups. The expression of hEpSCs labeled molecules was detected by immunofluorescence, and cell safety was detected by teratoma test in all groups. (1) Fluorescence microscopy showed that in the JAM-A over-expression (JAM-A(ov) EpSCs) group, the green fluorescence was mainly distributed in the cell membrane; in the JAM-A interference (JAM-A(kd) EpSCs) group and blank vector (GFP EpSCs) group, all cell bodies were luminous. Western blot showed that JAM-A protein was up-regulated in JAM-A(ov) EpSCs and down-regulated in JAM-A(kd) EpSCs. (2) Growth curves showed that hEpSCs entered the quick-growing phase 4 days after inoculation and reached the platform phase at day 7. JAM-A(ov) EpSCs proliferated more slowly than GFP EpSCs, while JAM-A(kd) EpSCs proliferated significantly faster than GFP EpSCs. (3) Immunofluorescence showed that the expression of transient amplification epidermal marker keratin 14, hEpSCs marker keratin I9 and β-integrin was down-regulated in JAM-A(kd) EpSCs group as compared to that in the GFP EpSCs group, and the expression of epidermal terminal differentiation marker K10 was negative in the JAM-A(kd) EpSCs group. There was no significant difference in the expression of specific molecules between JAM-A(ov) EpSCs and hEpSCs. (4) The result of teratoma test was negative in all groups. The proliferative ability of hEpSCs was increased markedly after down

  1. Epidermal growth-factor-induced transcript isoform variation drives mammary cell migration.

    Directory of Open Access Journals (Sweden)

    Wolfgang J Köstler

    Full Text Available Signal-induced transcript isoform variation (TIV includes alternative promoter usage as well as alternative splicing and alternative polyadenylation of mRNA. To assess the phenotypic relevance of signal-induced TIV, we employed exon arrays and breast epithelial cells, which migrate in response to the epidermal growth factor (EGF. We show that EGF rapidly--within one hour--induces widespread TIV in a significant fraction of the transcriptome. Importantly, TIV characterizes many genes that display no differential expression upon stimulus. In addition, similar EGF-dependent changes are shared by a panel of mammary cell lines. A functional screen, which utilized isoform-specific siRNA oligonucleotides, indicated that several isoforms play essential, non-redundant roles in EGF-induced mammary cell migration. Taken together, our findings highlight the importance of TIV in the rapid evolvement of a phenotypic response to extracellular signals.

  2. Preparation of epidermal growth factor (EGF) conjugated iron oxide nanoparticles and their internalization into colon cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Creixell, Mar [Department of Chemical Engineering, University of Puerto Rico, Mayagueez Campus, P.O. Box 9000, Mayagueez, PR 00681 (Puerto Rico); Department of Electronics, Faculty of Physics, University of Barcelona, Av. Diagonal 647, 08028 Barcelona (Spain); Herrera, Adriana P.; Ayala, Vanessa; Latorre-Esteves, Magda [Department of Chemical Engineering, University of Puerto Rico, Mayagueez Campus, P.O. Box 9000, Mayagueez, PR 00681 (Puerto Rico); Perez-Torres, Marianela [Department of Pharmaceutical Sciences, University of Puerto Rico-Medical Sciences Campus, PO Box 365067, San Juan, PR 00936 (Puerto Rico); Torres-Lugo, Madeline [Department of Chemical Engineering, University of Puerto Rico, Mayagueez Campus, P.O. Box 9000, Mayagueez, PR 00681 (Puerto Rico); Rinaldi, Carlos, E-mail: carlos.rinaldi@upr.ed [Department of Chemical Engineering, University of Puerto Rico, Mayagueez Campus, P.O. Box 9000, Mayagueez, PR 00681 (Puerto Rico)

    2010-08-15

    Epidermal growth factor (EGF) was conjugated with carboxymethyldextran (CMDx) coated iron oxide magnetic nanoparticles using carbodiimide chemistry to obtain magnetic nanoparticles that target the epidermal growth factor receptor (EGFR). Epidermal growth factor modified magnetic nanoparticles were colloidally stable when suspended in biological buffers such as PBS and cell culture media. Both targeted and non-targeted nanoparticles were incubated with CaCo-2 cancer cells, known to overexpress EGFR. Nanoparticle localization within the cell was visualized by confocal laser scanning microscopy and light microscopy using Prussian blue stain. Results showed that targeted magnetic nanoparticles were rapidly accumulated in both flask-shaped small vesicles and large circular endocytic structures. Internalization patterns suggest that both clathrin-dependent and clathrin-independent receptors mediated endocytosis mechanisms are responsible for nanoparticle internalization.

  3. Preparation of epidermal growth factor (EGF) conjugated iron oxide nanoparticles and their internalization into colon cancer cells

    Science.gov (United States)

    Creixell, Mar; Herrera, Adriana P.; Ayala, Vanessa; Latorre-Esteves, Magda; Pérez-Torres, Marianela; Torres-Lugo, Madeline; Rinaldi, Carlos

    2010-08-01

    Epidermal growth factor (EGF) was conjugated with carboxymethyldextran (CMDx) coated iron oxide magnetic nanoparticles using carbodiimide chemistry to obtain magnetic nanoparticles that target the epidermal growth factor receptor (EGFR). Epidermal growth factor modified magnetic nanoparticles were colloidally stable when suspended in biological buffers such as PBS and cell culture media. Both targeted and non-targeted nanoparticles were incubated with CaCo-2 cancer cells, known to overexpress EGFR. Nanoparticle localization within the cell was visualized by confocal laser scanning microscopy and light microscopy using Prussian blue stain. Results showed that targeted magnetic nanoparticles were rapidly accumulated in both flask-shaped small vesicles and large circular endocytic structures. Internalization patterns suggest that both clathrin-dependent and clathrin-independent receptors mediated endocytosis mechanisms are responsible for nanoparticle internalization.

  4. Epidermal cell proliferation and terminal differentiation in skin organ culture after topical exposure to sodium dodecyl sulphate

    NARCIS (Netherlands)

    Sandt, J.J.M. van de; Bos, T.A.; Rutten, A.A.J.J.L.

    1995-01-01

    Epidermal cell proliferation and differentiation were investigated in vitro after exposure to the anionic surfactant sodium dodecyl sulfate (SDS). Human skin organ cultures were exposed topically to various concentrations of SDS for 22 h, after which the irritant was removed. Cell proliferation was

  5. Pathways for epidermal cell differentiation via the homeobox gene GLABRA2: update on the roles of the classic regulator.

    Science.gov (United States)

    Lin, Qing; Qing, Lin; Aoyama, Takashi

    2012-10-01

    Recent plant development studies have identified regulatory pathways for epidermal cell differentiation in Arabidopsis thaliana. Interestingly, some of such pathways contain transcriptional networks with a common structure in which the homeobox gene GLABLA2 (GL2) is downstream of the transactivation complex consisting of MYB, bHLH, and WD40 proteins. Here, we review the role of GL2 as an output device of the conserved network, and update the knowledge of epidermal cell differentiation pathways downstream of GL2. Despite the consistent position of GL2 within the network, its role in epidermal tissues varies; in the root epidermis, GL2 promotes non-hair cell differentiation after cell pattern formation, whereas in the leaf epidermis, it is likely to be involved in both pattern formation and differentiation of trichomes. GL2 expression levels act as quantitative factors for initiation of cell differentiation in the root and leaf epidermis; the quantity of hairless cells in non-root hair cell files is reduced by gl2 mutations in a semi-dominant manner, and entopically additive expression of GL2 and a heterozygous gl2 mutation increase and decrease the number of trichomes, respectively. Although few direct target genes have been identified, evidence from genetic and expression analyses suggests that GL2 directly regulates genes with various hierarchies in epidermal cell differentiation pathways. © 2012 Institute of Botany, Chinese Academy of Sciences.

  6. Pathways for Epidermal Cell Differentiation via the Homeobox Gene GLABRA2: Update on the Roles of the Classic Regulator

    Institute of Scientific and Technical Information of China (English)

    Lin Qing; Takashi Aoyama

    2012-01-01

    Recent plant development studies have identified regulatory pathways for epidermal cell differentiation in Arabidopsis thaliana.Interestingly,some of such pathways contain transcriptional networks with a common structure in which the homeobox gene GLABLA2 (GL2) is downstream of the transactivation complex consisting of MYB,bHLH,and WD40 proteins.Here,we review the role of GL2 as an output device of the conserved network,and update the knowledge of epidermal cell differentiation pathways downstream of GL2.Despite the consistent position of GL2 within the network,its role in epidermal tissues varies; in the root epidermis,GL2 promotes non-hair cell differentiation after cell pattern formation,whereas in the leaf epidermis,it is likely to be involved in both pattern formation and differentiation of trichomes.GL2 expression levels act as quantitative factors for initiation of cell differentiation in the root and leaf epidermis; the quantity of hairless cells in non-root hair cell files is reduced by g/2 mutations in a semi-dominant manner,and entopically additive expression of GL2 and a heterozygous g/2 mutation increase and decrease the number of trichomes,respectively.Although few direct target genes have been identified,evidence from genetic and expression analyses suggests that GL2 directly regulates genes with various hierarchies in epidermal cell differentiation pathways.

  7. Structure and function of the interphotoreceptor matrix surrounding retinal photoreceptor cells.

    Science.gov (United States)

    Ishikawa, Makoto; Sawada, Yu; Yoshitomi, Takeshi

    2015-04-01

    The interphotoreceptor matrix (IPM) is a highly organized structure with interconnected domains surrounding cone and rod photoreceptor cells and extends throughout the subretinal space. Based on known roles of the extracellular matrix in other tissues, the IPM is thought to have several prominent functions including serving as a receptor for growth factors, regulating retinoid transport, participating in cytoskeletal organization in surrounding cells, and regulation of oxygen and nutrient transport. In addition, a number of studies suggest that the IPM also may play a significant role in the etiology of retinal degenerative disorders. In this review, we describe the present knowledge concerning the structure and function of the IPM under physiological and pathological conditions. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Tissue-engineered dermo-epidermal skin grafts prevascularized with adipose-derived cells.

    Science.gov (United States)

    Klar, Agnieszka S; Güven, Sinan; Biedermann, Thomas; Luginbühl, Joachim; Böttcher-Haberzeth, Sophie; Meuli-Simmen, Claudia; Meuli, Martin; Martin, Ivan; Scherberich, Arnaud; Reichmann, Ernst

    2014-06-01

    The major problem in skin grafting is that tissue-engineered skin grafts after their transplantation are initially entirely dependent on diffusion. Since this process is slow and inefficient, nutrients, growth factors, and oxygen will insufficiently be supplied and the regenerating graft will undergo a physiological crisis, resulting in scar-like dermal structures and shrinkage. The tissue-engineering of a vascular network in human dermo-epidermal skin substitutes (DESS) is a promising approach to overcome this limitation. Here we report, for the first time, on the use of the adipose stromal vascular fraction (SVF)-derived endothelial cell population to tissue-engineer DESS containing a highly efficient capillary plexus. To develop vascular networks in vitro, we employed optimized 3D fibrin or collagen type I hydrogel systems. Upon transplantation onto immune-deficient rats, these pre-formed vascular networks anastomosed to the recipient's vasculature within only four days. As a consequence, the neo-epidermis efficiently established tissue homeostasis, the dermis underwent almost no contraction, and showed sustained epidermal coverage in vivo. Overall, the here described rapid and efficient perfusion of SVF-based skin grafts opens new perspectives for the treatment of hitherto unmet clinical needs in burn/plastic surgery and dermatology. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. De novo epidermal regeneration using human eccrine sweat gland cells: higher competence of secretory over absorptive cells.

    Science.gov (United States)

    Pontiggia, Luca; Biedermann, Thomas; Böttcher-Haberzeth, Sophie; Oliveira, Carol; Braziulis, Erik; Klar, Agnieszka S; Meuli-Simmen, Claudia; Meuli, Martin; Reichmann, Ernst

    2014-06-01

    In our previous work, we showed that human sweat gland-derived epithelial cells represent an alternative source of keratinocytes to grow a near normal autologous epidermis. The role of subtypes of sweat gland cells in epidermal regeneration and maintenance remained unclear. In this study, we compare the regenerative potential of both secretory and absorptive sweat gland cell subpopulations. We demonstrate the superiority of secretory over absorptive cells in forming a new epidermis on two levels: first, the proliferative and colony-forming efficiencies in vitro are significantly higher for secretory cells (SCs), and second, SCs show a higher frequency of successful epidermis formation as well as an increase in the thickness of the formed epidermis in the in vitro and in vivo functional analyses using a 3D dermo-epidermal skin model. However, the ability of forming functional skin substitutes is not limited to SCs, which supports the hypothesis that multiple subtypes of sweat gland epithelial cells hold regenerative properties, while the existence and exact localization of a keratinocyte stem cell population in the human eccrine sweat gland remain elusive.

  10. Inhibition of epidermal growth factor receptor expression by RNA interference in A549 cells

    Institute of Scientific and Technical Information of China (English)

    MinZHANG; XinZHANG; Chun-xueBAI; JieCHEN; MinQWEI

    2004-01-01

    AIM: To investigate the biological features of A549 cells in which epidermal growth factor (EGF) receptors expression were suppressed by RNA interference (RNAi). METHODS: A549 cells were transfected using short small interfering RNAs (siRNAs) formulated with Lipofectamine 2000. The EGF receptor numbers were determined by Western blotting and flowcytometry. The antiproliferative effects of sequence specific double stranded RNA (dsRNA) were assessed using cell count, colony assay and scratch assay. The chemosensitivity of transfected cells to cisplatin was measured by MTT. RESULTS: Sequence specific dsRNA-EGFR down-regulated EGF receptor expression dramatically. Compared with the control group, dsRNA-EGFR reduced the cell number by 85.0 %, decreased the colonies by 63.3 %, inhibited the migration by 87.2 %, and increased the sensitivity of A549 to cisplatin by four-fold. CONCLUSION: Sequence specific dsRNA-EGFR were capable of suppressing EGF receptor expression, hence significantly inhibiting cellular proliferation and motility, and enhancing chemosensitivity of A549 cells to cisplatin. The successful application of dsRNA-EGFR for inhibition of proliferation in EGF receptor overexpressing cells can help extend the list of available therapeutic modalities in the treatment of non-small-cell lung carcinoma (NSCLC).

  11. Human eccrine sweat gland cells turn into melanin-uptaking keratinocytes in dermo-epidermal skin substitutes.

    Science.gov (United States)

    Böttcher-Haberzeth, Sophie; Biedermann, Thomas; Pontiggia, Luca; Braziulis, Erik; Schiestl, Clemens; Hendriks, Bart; Eichhoff, Ossia M; Widmer, Daniel S; Meuli-Simmen, Claudia; Meuli, Martin; Reichmann, Ernst

    2013-02-01

    Recently, Biedermann et al. (2010) have demonstrated that human eccrine sweat gland cells can develop a multilayered epidermis. The question still remains whether these cells can fulfill exclusive and very specific functional properties of epidermal keratinocytes, such as the incorporation of melanin, a feature absent in sweat gland cells. We added human melanocytes to eccrine sweat gland cells to let them develop into an epidermal analog in vivo. The interaction between melanocytes and sweat gland-derived keratinocytes was investigated. The following results were gained: (1) macroscopically, a pigmentation of the substitutes was seen 2-3 weeks after transplantation; (2) we confirmed the development of a multilayered, stratified epidermis with melanocytes distributed evenly throughout the basal layer; (3) melanocytic dendrites projected to suprabasal layers; and (4) melanin was observed to be integrated into former eccrine sweat gland cells. These skin substitutes were similar or equal to skin substitutes cultured from human epidermal keratinocytes. The only differences observed were a delay in pigmentation and less melanin uptake. These data suggest that eccrine sweat gland cells can form a functional epidermal melanin unit, thereby providing striking evidence that they can assume one of the most characteristic keratinocyte properties.

  12. Ultraviolet B light-induced apoptosis in human keratinocytes enriched with epidermal stem cells and normal keratinocytes

    Institute of Scientific and Technical Information of China (English)

    MEI Xue-ling; LIAN Shi

    2011-01-01

    Background The stem-cell compartment is the primary target for the accumulation of oncogenic mutations.Overexposure to solar ultraviolet radiation is responsible for the development and progression of >90% of skin cancers.Ultraviolet B (UVB) light-induced keratinocyte apoptosis is a strong preventive mechanism against carcinogenesis. The aim of this study was to isolate keratinocytes enriched with putative human epidermal stem cells and to investigate their apoptotic induction by UVB.Methods Keratinocytes enriched with putative human epidermal stem cells were isolated by adherence to collagen Ⅳ and the expressions of β1-integrin and p63 were investigated. Keratinocytes enriched with putative human epidermal stem cells and normal keratinocytes were irradiated with UVB at 0-80 mJ/cm2. The apoptotic response was investigated with phase-contrast microscopy, Hoechst 33342 staining, flow cytometry of annexin V/PI, and procaspase-3 Western blotting.Results Keratinocyte enriched with stem cells expressed high levels of p63 protein and β1-integrin and low level of pan-keratin (C11). In comparison to non-irradiated cells, significant apoptosis of keratinocyte enriched with stem cells was found with 40 and 80 mJ/cm2 UVB. However, significant apoptosis of normal keratinocytes was only found for 80 mJ/cm2 UVB.Conclusions Human epidermal stem cells can undergo apoptosis in response to UVB radiation and are more susceptible than other keratinocytes. The method could be used in vitro studies of human epidermal stem cells.

  13. Impact of mechanical stretch on the cell behaviors of bone and surrounding tissues

    Directory of Open Access Journals (Sweden)

    Hye-Sun Yu

    2016-02-01

    Full Text Available Mechanical loading is recognized to play an important role in regulating the behaviors of cells in bone and surrounding tissues in vivo. Many in vitro studies have been conducted to determine the effects of mechanical loading on individual cell types of the tissues. In this review, we focus specifically on the use of the Flexercell system as a tool for studying cellular responses to mechanical stretch. We assess the literature describing the impact of mechanical stretch on different cell types from bone, muscle, tendon, ligament, and cartilage, describing individual cell phenotype responses. In addition, we review evidence regarding the mechanotransduction pathways that are activated to potentiate these phenotype responses in different cell populations.

  14. The search for truth and freedom: ethical issues surrounding human cloning and stem cell research.

    Science.gov (United States)

    Bruce, Alex

    2002-02-01

    The reality of cloning and stem cell research has provoked wonder, fear and anger. These developments have the potential fundamentally to alter humanity. But how well informed is the range of views being expressed? Is progress being threatened by understandable but uninformed fears? Or are scientists rushing toward an ethical abyss, so concerned with what they can do that they never stop to ask what they should do? This article identifies some of the fears and hopes surrounding cloning and stem cell research. It aims to provoke ethical debate in evaluating such research.

  15. DEVELOPMENT OF PRIMARY CELL CULTURE FROM TAIL EPIDERMAL TISSUE OF KOI CARP (Cyprinus carpio koi

    Directory of Open Access Journals (Sweden)

    Lila Gardenia

    2014-06-01

    Full Text Available Primary cell culture from tail epidermal tissue of koi carp (Cyprinus carpio koi was developed. Cells were grown in Leibovits-15 medium supplemented with 20% fetal bovine serum and antibiotics (Penicillin/Streptomycin and Kanamycin. Cell growth was observed in a range of incubation temperature (17oC±2oC, 22oC±2oC, 27oC±2oC, and 32oC±2oC in order to determine the optimum temperature. The cells were able to grow at a range of temperature between 17oC to 32oC with optimal growth at 22oC. Primary cells infected with koi herpes virus produced typical cytopathic effects characterized by severe vacuolation and deformation of nuclei, which is consistent with those of previous reports. Artificial injection experiment by using supernatant koi herpes virus SKBM-1 isolate revealed that it could cause 90% mortality in infected fish within two weeks. PCR test with Sph I-5 specific primers carried out with DNA template from supernatant virus, pellet cell, and gills of infected fish showed positive results in all samples (molecular weight of DNA target 290 bp. The cells were found to be susceptible to koi herpes virus and can be used for virus propagation.

  16. Epidermal Growth Factor Receptor Mutation Enhances Expression of Cadherin-5 in Lung Cancer Cells.

    Science.gov (United States)

    Hung, Ming-Szu; Chen, I-Chuan; Lung, Jr-Hau; Lin, Paul-Yann; Li, Ya-Chin; Tsai, Ying-Huang

    2016-01-01

    Epidermal growth factor receptor (EGFR) activation has been shown to play a critical role in tumor angiogenesis. In this study, we investigate the correlation between EGFR mutations and cadherin-5 (CDH5), which is an angiogenic factor, in lung cancer cells. Increased expression CDH5 is observed in lung cancer cells with EGFR mutations. Stable lung cancer cell lines expressing mutant (exon 19 deletion E746-A750, and exon 21 missense mutation L858R) and wild type EGFR genes are established. A significantly higher expression of CDH5 is observed in exon 19 deletion stable lung cancer cells and mouse xenografts. Further studies show that expression of CDH5 is decreased after the inhibition of EGFR and downstream Akt pathways in lung cancer cells with EGFR mutation. In addition, mutant EGFR genes potentiates angiogenesis in lung cancer cells, which is inhibited by CDH5 siRNA, and potentiates migration and invasion in lung cancer cells. Our study shows that mutant EGFR genes are associated with overexpression of CDH5 through increased phosphorylation of EGFR and downstream Akt pathways. Our result may provide an insight into the association of mutant EGFR and CDH5 expression in lung cancer and aid further development of target therapy for NSCLC in the future.

  17. Epidermal Langerhans cells rapidly capture and present antigens from C-type lectin-targeting antibodies deposited in the dermis.

    Science.gov (United States)

    Flacher, Vincent; Tripp, Christoph H; Stoitzner, Patrizia; Haid, Bernhard; Ebner, Susanne; Del Frari, Barbara; Koch, Franz; Park, Chae Gyu; Steinman, Ralph M; Idoyaga, Juliana; Romani, Nikolaus

    2010-03-01

    Antigen-presenting cells can capture antigens that are deposited in the skin, including vaccines given subcutaneously. These include different dendritic cells (DCs) such as epidermal Langerhans cells (LCs), dermal DCs, and dermal langerin+ DCs. To evaluate access of dermal antigens to skin DCs, we used mAb to two C-type lectin endocytic receptors, DEC-205/CD205 and langerin/CD207. When applied to murine and human skin explant cultures, these mAbs were efficiently taken up by epidermal LCs. In addition, anti-DEC-205 targeted langerin+ CD103+ and langerin- CD103- mouse dermal DCs. Unexpectedly, intradermal injection of either mAb, but not isotype control, resulted in strong and rapid labeling of LCs in situ, implying that large molecules can diffuse through the basement membrane into the epidermis. Epidermal LCs targeted in vivo by ovalbumin-coupled anti-DEC-205 potently presented antigen to CD4+ and CD8+ T cells in vitro. However, to our surprise, LCs targeted through langerin were unable to trigger T-cell proliferation. Thus, epidermal LCs have a major function in uptake of lectin-binding antibodies under standard vaccination conditions.

  18. Human epidermal neural crest stem cells as candidates for cell-based therapies, disease modeling, and drug discovery.

    Science.gov (United States)

    Sieber-Blum, Maya

    2014-09-01

    In this review article I explore the suitability of human epidermal neural crest stem cells (hEPI-NCSC) for translational medicine. hEPI-NCSC are multipotent somatic stem cells that are derived from the embryonic neural crest. hEPI-NCSC are located in the bulge of hair follicles where they persist postnatally and into adulthood. Because of their location in the hairy skin and their migratory behavior, hEPI-NCSC can be easily isolated as a highly pure population of stem cells without the need for purification. Furthermore they can be expanded ex vivo into millions of stem cells, they do not form tumors in vivo, and they can undergo directed differentiation into crest and noncrest-derived cell types of clinical relevance. Taken together, these characteristics make hEPI-NCSC attractive candidates for cell-based therapies, drug discovery, and disease modeling. © 2014 Wiley Periodicals, Inc.

  19. Parabens and Human Epidermal Growth Factor Receptor Ligand Cross-Talk in Breast Cancer Cells.

    Science.gov (United States)

    Pan, Shawn; Yuan, Chaoshen; Tagmount, Abderrahmane; Rudel, Ruthann A; Ackerman, Janet M; Yaswen, Paul; Vulpe, Chris D; Leitman, Dale C

    2016-05-01

    Xenoestrogens are synthetic compounds that mimic endogenous estrogens by binding to and activating estrogen receptors. Exposure to estrogens and to some xenoestrogens has been associated with cell proliferation and an increased risk of breast cancer. Despite evidence of estrogenicity, parabens are among the most widely used xenoestrogens in cosmetics and personal-care products and are generally considered safe. However, previous cell-based studies with parabens do not take into account the signaling cross-talk between estrogen receptor α (ERα) and the human epidermal growth factor receptor (HER) family. We investigated the hypothesis that the potency of parabens can be increased with HER ligands, such as heregulin (HRG). The effects of HER ligands on paraben activation of c-Myc expression and cell proliferation were determined by real-time polymerase chain reaction, Western blots, flow cytometry, and chromatin immunoprecipitation assays in ERα- and HER2-positive human BT-474 breast cancer cells. Butylparaben (BP) and HRG produced a synergistic increase in c-Myc mRNA and protein levels in BT-474 cells. Estrogen receptor antagonists blocked the synergistic increase in c-Myc protein levels. The combination of BP and HRG also stimulated proliferation of BT-474 cells compared with the effects of BP alone. HRG decreased the dose required for BP-mediated stimulation of c-Myc mRNA expression and cell proliferation. HRG caused the phosphorylation of serine 167 in ERα. BP and HRG produced a synergistic increase in ERα recruitment to the c-Myc gene. Our results show that HER ligands enhanced the potency of BP to stimulate oncogene expression and breast cancer cell proliferation in vitro via ERα, suggesting that parabens might be active at exposure levels not previously considered toxicologically relevant from studies testing their effects in isolation. Pan S, Yuan C, Tagmount A, Rudel RA, Ackerman JM, Yaswen P, Vulpe CD, Leitman DC. 2016. Parabens and human epidermal

  20. Parabens and Human Epidermal Growth Factor Receptor Ligand Cross-Talk in Breast Cancer Cells

    Science.gov (United States)

    Pan, Shawn; Yuan, Chaoshen; Tagmount, Abderrahmane; Rudel, Ruthann A.; Ackerman, Janet M.; Yaswen, Paul; Vulpe, Chris D.; Leitman, Dale C.

    2015-01-01

    Background: Xenoestrogens are synthetic compounds that mimic endogenous estrogens by binding to and activating estrogen receptors. Exposure to estrogens and to some xenoestrogens has been associated with cell proliferation and an increased risk of breast cancer. Despite evidence of estrogenicity, parabens are among the most widely used xenoestrogens in cosmetics and personal-care products and are generally considered safe. However, previous cell-based studies with parabens do not take into account the signaling cross-talk between estrogen receptor α (ERα) and the human epidermal growth factor receptor (HER) family. Objectives: We investigated the hypothesis that the potency of parabens can be increased with HER ligands, such as heregulin (HRG). Methods: The effects of HER ligands on paraben activation of c-Myc expression and cell proliferation were determined by real-time polymerase chain reaction, Western blots, flow cytometry, and chromatin immunoprecipitation assays in ERα- and HER2-positive human BT-474 breast cancer cells. Results: Butylparaben (BP) and HRG produced a synergistic increase in c-Myc mRNA and protein levels in BT-474 cells. Estrogen receptor antagonists blocked the synergistic increase in c-Myc protein levels. The combination of BP and HRG also stimulated proliferation of BT-474 cells compared with the effects of BP alone. HRG decreased the dose required for BP-mediated stimulation of c-Myc mRNA expression and cell proliferation. HRG caused the phosphorylation of serine 167 in ERα. BP and HRG produced a synergistic increase in ERα recruitment to the c-Myc gene. Conclusion: Our results show that HER ligands enhanced the potency of BP to stimulate oncogene expression and breast cancer cell proliferation in vitro via ERα, suggesting that parabens might be active at exposure levels not previously considered toxicologically relevant from studies testing their effects in isolation. Citation: Pan S, Yuan C, Tagmount A, Rudel RA, Ackerman JM

  1. HAM56 and CD68 antigen presenting cells surrounding a sarcoidal granulomatous tattoo

    Directory of Open Access Journals (Sweden)

    Ana Maria Abreu Velez

    2011-01-01

    Full Text Available Context : Tattoos are produced by introducing colorants of various compositions into the skin, either accidentally or for cosmetic purposes. Case Report: A 62-year-old male presented with a cosmetic tattoo and requested a total excision of the lesion. Dermatopathologic analysis of the excised tissue with hematoxylin and eosin examination, as well as immunohistochemistry was performed. H&E staining demonstrated classic histologic features of a tattoo. Utilizing immunohistochemistry, dermal histiocytic antigen presenting cells stained with HAM56 and CD68 antibodies; the staining was present surrounding the tattoo pigment. Conclusions : We identified two macrophage markers (HAM56 and CD68 surrounding dermal tattoo pigment. A minimal dermal inflammatory immune was noted to the tattoo pigment. Moreover, the immune response and/or tolerance to tattoos is not well characterized. We suggest that tattoo materials and techniques could be utilized in therapeutic delivery for diseases such recessive dystrophic epidermolysis bullosa, potentially preventing immune rejection of gene therapy agents.

  2. Effect of Salinity on the Composition, Number and Size of Epidermal Cells along the Mature Blade of Wheat Leaves

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Salinity inhibits leaf growth in association with changes in cell size. The objective of this study was to determine the spatial distributions of the composition, number and dimensions of epidermal cells in the mature blades of leaf four of wheat seedlings under saline conditions. Plants were grown in loamy soil either with or without 120 mmol/L NaCl in a growth chamber, and harvested after leaf four was fully developed. The results of the spatial distribution analyses of width along the blade showed that salinity not only reduced the width of the leaf blade, but that it also altered the distribution pattern of blade width along the leaf axis. The reduction in the final size of the leaf blade was associated with a reduction in the total number of epidermal cells and in their widths and lengths. This study also revealed the spatial effects of salinity on the blade and epidermal cell dimensions along the leaf axis. In particular, salinity inhibited the total cell number for interstomatal, sister and elongated cells, implying that cell division in wheat leaves is inhibited by salinity. However, the lengths of interstomatal cells were not affected by salinity (unlike those for the sister and elongated cells), suggesting the relative contributions of cell length and numbers to the reduction in the final length of the blade under salinity is dependent on cell type.

  3. The epidermal cell structure of the secondary pollen presenter in Vangueria infausta (Rubiaceae: Vanguerieae) suggests a functional association with protruding onci in pollen grains.

    Science.gov (United States)

    Tilney, Patricia M; van Wyk, Abraham E; van der Merwe, Chris F

    2014-01-01

    Secondary pollen presentation is a well-known phenomenon in the Rubiaceae with particularly conspicuous pollen presenters occurring in the tribe Vanguerieae. These knob-like structures are formed by a modification of the upper portion of the style and stigma, together known as the stylar head complex. In the flower bud and shortly before anthesis, the anthers surrounding the stylar head complex dehisce and release pollen grains which adhere to the pollen presenter. The epidermal cells of the pollen presenter facing the anthers are radially elongated with a characteristic wall thickening encircling the anticlinal walls of each cell towards the distal end. These cells were studied in the pollen presenter of Vangueria infausta using electron and light microscopy in conjunction with histochemical tests and immunohistochemical methods. Other prominent thickenings of the cell wall were also observed on the distal and proximal walls. All these thickenings were found to be rich in pectin and possibly xyloglucan. The terms "thickenings of Igersheim" and "bands of Igersheim" are proposed to refer, respectively, to these wall structures in general and those encircling the anticlinal walls of each cell near the distal end. The epidermal cells have an intricate ultrastructure with an abundance of organelles, including smooth and rough endoplasmic reticulum, Golgi apparatus, mitochondria and secretory vesicles. This indicates that these cells are likely to have an active physiological role. The pollen grains possess prominent protruding onci and observations were made on their structure and development. Walls of the protruding onci are also rich in pectin. Pectins are hydrophilic and known to be involved in the dehydration and rehydration of pollen grains. We hypothesise that the thickenings of Igersheim, as well as the protruding onci of the pollen grains, are functionally associated and part of the adaptive syndrome of secondary pollen presentation, at least in the Vanguerieae.

  4. In vivo UVB irradiation induces clustering of Fas (CD95) on human epidermal cells

    DEFF Research Database (Denmark)

    Bang, Bo; Gniadecki, Robert; Larsen, Jørgen K

    2003-01-01

    a single dose of UVB irradiation. Normal healthy individuals were irradiated with three minimal erythema doses (MED) of UVB on forearm or buttock skin. Suction blisters from unirradiated and irradiated skin were raised, and Fas, FasL, and apoptosis of epidermal cells quantified by flow cytometry....... Clustering of Fas was from skin biopsied. Soluble FasL in suction blister fluid was quantified by ELISA. Flow cytometric analysis demonstrated increased expression intensity of Fas after irradiation, with 1.6-,2.2- and 2.7-fold increased median expression at 24, 48 and 72 h after irradiation, respectively (n...... of soluble FasL in suction blister fluid from UVB-irradiated skin did not differ from those in unirradiated skin (n=5). Confocal laser scanning microscopy showed a rapid clustering of Fas within 30 min after irradiation. A simultaneous clustering of the adapter signalling protein FADD suggested that Fas...

  5. Epidermal Growth Factor Receptor Mutations and Radiotherapy 
in Non-small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Xing ZHONG

    2013-03-01

    Full Text Available Radiotherapy plays a pivotal role in the treatment for lung cancer. Epidermal growth factor receptor (EGFR mutation in non-small cell lung cancer (NSCLC which predicts tyrosine kinase inhibitor (TKI treatment response may also has effect on radiation response. NSCLC harboring kinase-domain mutations in EGFR exhibits enhanced radio-sensitivity due to dramatically diminished capacity to resolve radiation-induced DSBs (DNA double-strand breaks associating with the inefficiency of EGFR nuclear translocation. Recently, several preliminary clinical studies show certain efficacy of concurrent EGFR tyrosine kinase inhibitors and radiotherapy. However its further response in EGFR-mutated NSCLC is unclear. The correlation between EGFR mutation genotype and the radiotherapy response and clinical outcome is worthy of further study.

  6. IL-4 Downregulates IL-1β and IL-6 and Induces GATA3 in Psoriatic Epidermal Cells: Route of Action of a Th2 Cytokine.

    Science.gov (United States)

    Onderdijk, Armanda J; Baerveldt, Ewout M; Kurek, Dorota; Kant, Marius; Florencia, Edwin F; Debets, Reno; Prens, Errol P

    2015-08-15

    Clinical improvement of psoriasis induced by IL-4 treatment has been ascribed to changes in dermal inflammatory cells, such as activation of Th2 cells and tolerization of dendritic cells by suppressing IL-23 production. The pathologic epidermal alterations in psoriatic lesional skin include increased epidermal expression of IL-1β, IL-6, S100A7, and human β-defensin 2 (hBD2) and a downregulated expression of the epidermal transcription factor GATA3. Effects of IL-4 on the epidermal compartment of psoriasis lesions were not previously investigated. Therefore, we investigated whether IL-4 directly affects abovementioned psoriatic markers in the epidermal compartment. We cultured freshly isolated psoriatic epidermal cells, whole psoriatic and healthy skin biopsies, human keratinocytes and Langerhans cells with IL-4. The secretion of IL-1β and IL-6 by psoriatic epidermal cells was inhibited by IL-4 via transcriptional and posttranscriptional mechanisms, respectively. In normal skin, IL-4 inhibited IL-1β- and IL-17A-induced hBD2 expression in vitro. In addition, IL-4 reduced the protein expression of hBD2 in psoriatic skin biopsies and induced phospho-STAT6 protein. Epidermal GATA3 mRNA and protein were significantly upregulated by IL-4 in epidermal cells and keratinocytes. Our data argue that IL-4 improves psoriasis not only via modification/induction of Th2 cells and type II dendritic cells, but also via direct inhibition of inflammatory cytokines in resident IL-4R-expressing epidermal cells and thereby alters the psoriatic skin phenotype toward a healthy skin phenotype.

  7. Long-Term Stability and Safety of Transgenic Cultured Epidermal Stem Cells in Gene Therapy of Junctional Epidermolysis Bullosa

    Directory of Open Access Journals (Sweden)

    Laura De Rosa

    2014-01-01

    Full Text Available We report a long-term follow-up (6.5 years of a phase I/II clinical trial envisaging the use of autologous genetically modified cultured epidermal stem cells for gene therapy of junctional epidermolysis bullosa, a devastating genetic skin disease. The critical goals of the trial were to evaluate the safety and long-term persistence of genetically modified epidermis. A normal epidermal-dermal junction was restored and the regenerated transgenic epidermis was found to be fully functional and virtually indistinguishable from a normal control. The epidermis was sustained by a discrete number of long-lasting, self-renewing transgenic epidermal stem cells that maintained the memory of the donor site, whereas the vast majority of transduced transit-amplifying progenitors were lost within the first few months after grafting. These data pave the way for the safe use of epidermal stem cells in combined cell and gene therapy for genetic skin diseases.

  8. Epidermal growth factor and ras regulate gene expression in GH4 pituitary cells by separate, antagonistic signal transduction pathways

    Energy Technology Data Exchange (ETDEWEB)

    Pickett, C.A.; Gutierrez-Hartmann, A. [Univ. of Colorado Health Sciences Center, Denver, CO (United States)

    1995-12-01

    This report discusses the role of the epidermal growth factor (EGF) in promoting activation of the rat prolactin promoter in neuroendocrine cells via a Ras-independent mechanism. It also discusses the role of phosphotransferases in mediating EGF response. 32 refs., 8 figs., 1 tab.

  9. Outcome of burns treated with autologous cultured proliferating epidermal cells: a prospective randomized multicenter intrapatient comparative trial

    NARCIS (Netherlands)

    Gardien, K.L.M.; Marck, R.E.; Bloemen, M.C.T.; Waaijman, T.; Gibbs, S.; Uhlrich, M.M.W.; Middelkoop, E.

    2016-01-01

    Standard treatment for large burns is transplantation with meshed split skin autografts (SSGs). A disadvantage of this treatment is that healing is accompanied by scar formation. Application of autologous epidermal cells (keratinocytes and melanocytes) may be a suitable therapeutic alternative, sinc

  10. Epidermal growth factor promotes proliferation of dermal papilla cells via Notch signaling pathway.

    Science.gov (United States)

    Zhang, Haihua; Nan, Weixiao; Wang, Shiyong; Zhang, Tietao; Si, Huazhe; Wang, Datao; Yang, Fuhe; Li, Guangyu

    2016-08-01

    The effect of epidermal growth factor (EGF) on the development and growth of hair follicle is controversial. In the present study, 2-20 ng/ml EGF promoted the growth of mink hair follicles in vitro, whereas 200 ng/ml EGF inhibited follicle growth. Further, dermal papilla (DP) cells, a group of mesenchymal cells that govern hair follicle development and growth, were isolated and cultured in vitro. Treatment with or forced expression of EGF accelerated proliferation and induced G1/S transition in DP cells. Moreover, EGF upregulated the expression of DP mesenchymal genes, such as alkaline phosphatase (ALP) and insulin-like growth factor (IGF-1), as well as the Notch pathway molecules including Notch1, Jagged1, Hes1 and Hes5. In addition, inhibition of Notch signaling pathway by DAPT significantly reduced the basal and EGF-enhanced proliferation rate, and also suppressed cell cycle progression. We also show that the expression of several follicle-regulatory genes, such as Survivin and Msx2, were upregulated by EGF, and was inhibited by DAPT. In summary, our study demonstrates that the concentration of EGF is critical for the switch between hair follicle growth and inhibition, and EGF promotes DP cell proliferation via Notch signaling pathway.

  11. Dissection of Arabidopsis ADP-RIBOSYLATION FACTOR 1 Function in Epidermal Cell PolarityW⃞

    Science.gov (United States)

    Xu, Jian; Scheres, Ben

    2005-01-01

    Vesicle trafficking is essential for the generation of asymmetries, which are central to multicellular development. Core components of the vesicle transport machinery, such as ADP-ribosylation factor (ARF) GTPases, have been studied primarily at the single-cell level. Here, we analyze developmental functions of the ARF1 subclass of the Arabidopsis thaliana multigene ARF family. Six virtually identical ARF1 genes are ubiquitously expressed, and single loss-of-function mutants in these genes reveal no obvious developmental phenotypes. Fluorescence colocalization studies reveal that ARF1 is localized to the Golgi apparatus and endocytic organelles in both onion (Allium cepa) and Arabidopsis cells. Apical-basal polarity of epidermal cells, reflected by the position of root hair outgrowth, is affected when ARF1 mutants are expressed at early stages of cell differentiation but after they exit mitosis. Genetic interactions during root hair tip growth and localization suggest that the ROP2 protein is a target of ARF1 action, but its localization is slowly affected upon ARF1 manipulation when compared with that of Golgi and endocytic markers. Localization of a second potential target of ARF1 action, PIN2, is also affected with slow kinetics. Although extreme redundancy precludes conventional genetic dissection of ARF1 functions, our approach separates different ARF1 downstream networks involved in local and specific aspects of cell polarity. PMID:15659621

  12. Effects of epidermal growth factor on glycolysis in A431 cells.

    Science.gov (United States)

    Baulida, J; Onetti, R; Bassols, A

    1992-03-31

    A431 cells were treated with epidermal growth factor (EGF) to study the mechanism by which this factor accelerates the glycolytic flux. After EGF treatment, fructose-2,6-bisphosphate (Fru-2,6-P2) levels rose up to 2-fold. This change correlated with an increase in phosphofructokinase-2 activity, which was not due to a change in the transcription or translation of the enzyme, neither in the amount of enzyme. PK-C does not appear to be involved in the signalling mechanism since EGF was equally potent in PK-C depleted cells than in control cells. The increase in Fru-2,6-P2 levels was lower and more transient in cells treated with EGF in a calcium-free medium than in the presence of the cation, and it was restored by the addition of calcium to the medium. These results suggest a possible role for calcium-mediated pathways in the control of Fru-2,6-P2 levels in A431 cells.

  13. Constitutively activated barley ROPs modulate epidermal cell size, defense reactions and interactions with fungal leaf pathogens.

    Science.gov (United States)

    Pathuri, Indira Priyadarshini; Zellerhoff, Nina; Schaffrath, Ulrich; Hensel, Götz; Kumlehn, Jochen; Kogel, Karl-Heinz; Eichmann, Ruth; Hückelhoven, Ralph

    2008-12-01

    RHO-like monomeric G-proteins of plants (ROPs, also called RACs), are involved in plant development and interaction with the environment. The barley (Hordeum vulgare) ROP protein HvRACB has been shown to be required for entry of the biotrophic powdery mildew fungus Blumeria graminis f.sp. hordei (Bgh) into living host cells. To get a deeper insight into evolutionarily conserved functions of ROPs in cell polarity and pathogen responses, we stably expressed constitutively activated (CA) mutant variants of different barley ROPs (HvRACB, HvRAC1, HvRAC3) in barley. CA HvROPs induced epidermal cell expansion and/or abolished polarity in tip growing root hairs. All three CA HvROPs enhanced susceptibility of barley to penetration by Bgh whereas only CA HvRAC1 supported whole cell H(2)O(2) production in non-penetrated cells. Despite increasing penetration by Bgh, CA HvRAC1 promoted callose deposition at sites of fungal attack and resistance to penetration by Magnaporthe oryzae. The data show an involvement of ROPs in polar growth processes of the monocot barley and in responses to fungal pathogens with different life style.

  14. Trafficking through COPII stabilises cell polarity and drives secretion during Drosophila epidermal differentiation.

    Directory of Open Access Journals (Sweden)

    Michaela Norum

    Full Text Available BACKGROUND: The differentiation of an extracellular matrix (ECM at the apical side of epithelial cells implies massive polarised secretion and membrane trafficking. An epithelial cell is hence engaged in coordinating secretion and cell polarity for a correct and efficient ECM formation. PRINCIPAL FINDINGS: We are studying the molecular mechanisms that Drosophila tracheal and epidermal cells deploy to form their specific apical ECM during differentiation. In this work we demonstrate that the two genetically identified factors haunted and ghost are essential for polarity maintenance, membrane topology as well as for secretion of the tracheal luminal matrix and the cuticle. We show that they code for the Drosophila COPII vesicle-coating components Sec23 and Sec24, respectively, that organise vesicle transport from the ER to the Golgi apparatus. CONCLUSION: Taken together, epithelial differentiation during Drosophila embryogenesis is a concerted action of ECM formation, plasma membrane remodelling and maintenance of cell polarity that all three rely mainly, if not absolutely, on the canonical secretory pathway from the ER over the Golgi apparatus to the plasma membrane. Our results indicate that COPII vesicles constitute a central hub for these processes.

  15. Trafficking through COPII Stabilises Cell Polarity and Drives Secretion during Drosophila Epidermal Differentiation

    Science.gov (United States)

    Norum, Michaela; Tång, Erika; Chavoshi, Tina; Schwarz, Heinz; Linke, Dirk; Uv, Anne; Moussian, Bernard

    2010-01-01

    Background The differentiation of an extracellular matrix (ECM) at the apical side of epithelial cells implies massive polarised secretion and membrane trafficking. An epithelial cell is hence engaged in coordinating secretion and cell polarity for a correct and efficient ECM formation. Principal Findings We are studying the molecular mechanisms that Drosophila tracheal and epidermal cells deploy to form their specific apical ECM during differentiation. In this work we demonstrate that the two genetically identified factors haunted and ghost are essential for polarity maintenance, membrane topology as well as for secretion of the tracheal luminal matrix and the cuticle. We show that they code for the Drosophila COPII vesicle-coating components Sec23 and Sec24, respectively, that organise vesicle transport from the ER to the Golgi apparatus. Conclusion Taken together, epithelial differentiation during Drosophila embryogenesis is a concerted action of ECM formation, plasma membrane remodelling and maintenance of cell polarity that all three rely mainly, if not absolutely, on the canonical secretory pathway from the ER over the Golgi apparatus to the plasma membrane. Our results indicate that COPII vesicles constitute a central hub for these processes. PMID:20520821

  16. Epoc-1: a POU-domain gene expressed in murine epidermal basal cells and thymic stromal cells.

    Science.gov (United States)

    Yukawa, K; Yasui, T; Yamamoto, A; Shiku, H; Kishimoto, T; Kikutani, H

    1993-11-15

    POU-domain transcription factors are known as developmental regulators which control organ development and cell phenotypes. In order to clarify the roles of POU-domain transcription factors in cell differentiation, we cloned a novel POU family gene, Epoc-1, from a murine thymus cDNA library. The amino acid (aa) sequence of the POU-specific domain of Epoc-1 is almost identical to those of Oct-1 and Oct-2. However, within the POU-homeodomain, 13 out of 60 aa differ between Epoc-1 and Oct-2. Recombinant Epoc-1 products were found to bind specifically to the octamer sequence. Epoc-1 was found to be expressed in skin, thymus, stomach and testis. In situ hybridization experiments and RNase protection assays indicated that Epoc-1 is expressed in the epidermal basal cells of the skin, which contain stem cells unipotent for keratinocyte differentiation and in thymic stromal elements. These results suggest that Epoc-1 might be one of the developmental regulators which controls epidermal development and thymic organogenesis.

  17. Human amniotic fluid derived cells can competently substitute dermal fibroblasts in a tissue-engineered dermo-epidermal skin analog

    OpenAIRE

    2013-01-01

    PURPOSE: Human amniotic fluid comprises cells with high differentiation capacity, thus representing a potential cell source for skin tissue engineering. In this experimental study, we investigated the ability of human amniotic fluid derived cells to substitute dermal fibroblasts and support epidermis formation and stratification in a humanized animal model. METHODS: Dermo-epidermal skin grafts with either amniocytes or with fibroblasts in the dermis were compared in a rat model. Full-thicknes...

  18. 1)Jarid2 regulates mouse epidermal stem cell activation and differentiation ; 2)Tumor heterogeneity and metastasis-initiation in human squamous cell carcinoma

    OpenAIRE

    Mejetta, Stefania

    2013-01-01

    Jarid2 is required for the genomic recruitment of the polycomb repressive complex-2 (PRC2) in embryonic stem cells. However, its specific role during late development and adult tissues remains largely uncharacterized. In this first part of my thesis, we show that deletion of Jarid2 in mouse epidermis reduces the proliferation and potentiates the differentiation of postnatal epidermal progenitors, without affecting epidermal development. In neonatal epidermis, Jarid2 deficien...

  19. The Antiaging Properties of Andrographis paniculata by Activation Epidermal Cell Stemness

    Directory of Open Access Journals (Sweden)

    Jiyoung You

    2015-09-01

    Full Text Available Andrographis paniculata (A. paniculata, Chuanxinlian, a medicinal herb with an extremely bitter taste that is native to China and other parts of Southeast Asia, possesses immense therapeutic value; however, its therapeutic properties have rarely been applied in the field of skin care. In this study, we investigated the effect of an A. paniculata extract (APE on human epidermal stem cells (EpSCs, and confirmed its anti-aging effect through in vitro, ex vivo, and in vivo study. An MTT assay was used to determine cell proliferation. A flow cytometric analysis, with propidium iodide, was used to evaluate the cell cycle. The expression of integrin β1 (CD29, the stem cell marker, was detected with antibodies, using flow cytometry in vitro, and immunohistochemical assays in ex vivo. Type 1 collagen and VEGF (vascular endothelial growth factor were measured using an enzyme-linked immunosorbent assay (ELISA. During the clinical study, skin hydration, elasticity, wrinkling, sagging, and dermal density were evaluated before treatment and at four and eight weeks after the treatment with the test product (containing the APE on the face. The proliferation of the EpSCs, treated with the APE, increased significantly. In the cell cycle analysis, the APE increased the G2/M and S stages in a dose-dependent manner. The expression of integrin β1, which is related to epidermal progenitor cell expansion, was up-regulated in the APE-treated EpSCs and skin explants. In addition, the production of VEGF in the EpSCs increased significantly in response to the APE treatment. Consistent with these results, the VEGF and APE-treated EpSCs conditioned medium enhanced the Type 1 collagen production in normal human fibroblasts (NHFs. In the clinical study, the APE improved skin hydration, dermal density, wrinkling, and sagging significantly. Our findings revealed that the APE promotes a proliferation of EpSCs, through the up-regulation of the integrin β1 and VEGF expression

  20. The Histochemical Characterization of the Glycoconjugates in the Epidermal Mucous Cells of the Red Californian Earthworm, Eisenia foetida

    Directory of Open Access Journals (Sweden)

    Kenan Çinar

    2014-01-01

    Full Text Available The aim of this study was to characterize the nature and regional distribution of the glycoconjugates secreted by epidermal mucous cells in Eisenia foetida (Annelida. Specimens were divided into six regions from anterior to posterior. The histochemistry was carried out by using standard histochemical methods. Histochemical staining properties of glycoconjugates in epidermal mucous cells were determined regionally. The epidermis of all regions contained strong to stronger PAS (+ cells in various degrees. The epidermis of the first, fourth, fifth, and sixth regions had strong to stronger AB pH 2.5 (+ cells. On the contrary, all regions contained weak to moderate AB pH 0.5 and AB pH 1.0 (+ cells. Most of mucous cells in epidermis of the first region contained both PAS (+ and AB (+ mucosubstances. All regions included weaker to weak AF (+ cells. All regions featured KOH/PAS (+ cells, with a slight reduction in reaction intensity in the epidermis of the last three regions. In this context, the different staining patterns observed in epidermal mucous cells hinted at their functional roles with respect to production of mucus with different physical properties. This study provided comprehensive information about the regional distribution patterns of the glycoconjugates and an opportunity to compare their distributional patterns in other annelids.

  1. A single epidermal stem cell strategy for safe ex vivo gene therapy.

    Science.gov (United States)

    Droz-Georget Lathion, Stéphanie; Rochat, Ariane; Knott, Graham; Recchia, Alessandra; Martinet, Danielle; Benmohammed, Sara; Grasset, Nicolas; Zaffalon, Andrea; Besuchet Schmutz, Nathalie; Savioz-Dayer, Emmanuelle; Beckmann, Jacques Samuel; Rougemont, Jacques; Mavilio, Fulvio; Barrandon, Yann

    2015-02-27

    There is a widespread agreement from patient and professional organisations alike that the safety of stem cell therapeutics is of paramount importance, particularly for ex vivo autologous gene therapy. Yet current technology makes it difficult to thoroughly evaluate the behaviour of genetically corrected stem cells before they are transplanted. To address this, we have developed a strategy that permits transplantation of a clonal population of genetically corrected autologous stem cells that meet stringent selection criteria and the principle of precaution. As a proof of concept, we have stably transduced epidermal stem cells (holoclones) obtained from a patient suffering from recessive dystrophic epidermolysis bullosa. Holoclones were infected with self-inactivating retroviruses bearing a COL7A1 cDNA and cloned before the progeny of individual stem cells were characterised using a number of criteria. Clonal analysis revealed a great deal of heterogeneity among transduced stem cells in their capacity to produce functional type VII collagen (COLVII). Selected transduced stem cells transplanted onto immunodeficient mice regenerated a non-blistering epidermis for months and produced a functional COLVII. Safety was assessed by determining the sites of proviral integration, rearrangements and hit genes and by whole-genome sequencing. The progeny of the selected stem cells also had a diploid karyotype, was not tumorigenic and did not disseminate after long-term transplantation onto immunodeficient mice. In conclusion, a clonal strategy is a powerful and efficient means of by-passing the heterogeneity of a transduced stem cell population. It guarantees a safe and homogenous medicinal product, fulfilling the principle of precaution and the requirements of regulatory affairs. Furthermore, a clonal strategy makes it possible to envision exciting gene-editing technologies like zinc finger nucleases, TALENs and homologous recombination for next-generation gene therapy.

  2. Effects of epidermal growth factor receptor kinase inhibition on radiation response in canine osteosarcoma cells.

    Science.gov (United States)

    Mantovani, Fernanda B; Morrison, Jodi A; Mutsaers, Anthony J

    2016-05-31

    Radiation therapy is a palliative treatment modality for canine osteosarcoma, with transient improvement in analgesia observed in many cases. However there is room for improvement in outcome for these patients. It is possible that the addition of sensitizing agents may increase tumor response to radiation therapy and prolong quality of life. Epidermal growth factor receptor (EGFR) expression has been documented in canine osteosarcoma and higher EGFR levels have been correlated to a worse prognosis. However, effects of EGFR inhibition on radiation responsiveness in canine osteosarcoma have not been previously characterized. This study examined the effects of the small molecule EGFR inhibitor erlotinib on canine osteosarcoma radiation responses, target and downstream protein expression in vitro. Additionally, to assess the potential impact of treatment on tumor angiogenesis, vascular endothelial growth factor (VEGF) levels in conditioned media were measured. Erlotinib as a single agent reduced clonogenic survival in two canine osteosarcoma cell lines and enhanced the impact of radiation in one out of three cell lines investigated. In cell viability assays, erlotinib enhanced radiation effects and demonstrated single agent effects. Erlotinib did not alter total levels of EGFR, nor inhibit downstream protein kinase B (PKB/Akt) activation. On the contrary, erlotinib treatment increased phosphorylated Akt in these osteosarcoma cell lines. VEGF levels in conditioned media increased after erlotinib treatment as a single agent and in combination with radiation in two out of three cell lines investigated. However, VEGF levels decreased with erlotinib treatment in the third cell line. Erlotinib treatment promoted modest enhancement of radiation effects in canine osteosarcoma cells, and possessed activity as a single agent in some cell lines, indicating a potential role for EGFR inhibition in the treatment of a subset of osteosarcoma patients. The relative radioresistance of

  3. Involvement of C2H2 zinc finger proteins in the regulation of epidermal cell fate determination in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    An Yan; Minjie Wu; Yongqin Zhao; Aidong Zhang; Bohan Liu; John Schiefelbein; Yinbo Gan

    2014-01-01

    Cell fate determination is a basic developmental process during the growth of multicellular organisms. Trichomes and root hairs of Arabidopsis are both readily accessible structures originating from the epidermal cells of the aerial tissues and roots respectively, and they serve as excellent models for understanding the molecular mecha-nisms controlling cell fate determination and cell morphogen-esis. The regulation of trichome and root hair formation is a complex program that consists of the integration of hormonal signals with a large number of transcriptional factors, including MYB and bHLH transcriptional factors. Studies during recent years have uncovered an important role of C2H2 type zinc finger proteins in the regulation of epidermal cell fate determination. Here in this minireview we briefly summarize the involvement of C2H2 zinc finger proteins in the control of trichome and root hair formation in Arabidopsis.

  4. Sphingosine-1-phosphate mediates epidermal growth factor-induced muscle satellite cell activation

    Energy Technology Data Exchange (ETDEWEB)

    Nagata, Yosuke, E-mail: cynagata@mail.ecc.u-tokyo.ac.jp; Ohashi, Kazuya; Wada, Eiji; Yuasa, Yuki; Shiozuka, Masataka; Nonomura, Yoshiaki; Matsuda, Ryoichi

    2014-08-01

    Skeletal muscle can regenerate repeatedly due to the presence of resident stem cells, called satellite cells. Because satellite cells are usually quiescent, they must be activated before participating in muscle regeneration in response to stimuli such as injury, overloading, and stretch. Although satellite cell activation is a crucial step in muscle regeneration, little is known of the molecular mechanisms controlling this process. Recent work showed that the bioactive lipid sphingosine-1-phosphate (S1P) plays crucial roles in the activation, proliferation, and differentiation of muscle satellite cells. We investigated the role of growth factors in S1P-mediated satellite cell activation. We found that epidermal growth factor (EGF) in combination with insulin induced proliferation of quiescent undifferentiated mouse myoblast C2C12 cells, which are also known as reserve cells, in serum-free conditions. Sphingosine kinase activity increased when reserve cells were stimulated with EGF. Treatment of reserve cells with the D-erythro-N,N-dimethylsphingosine, Sphingosine Kinase Inhibitor, or siRNA duplexes specific for sphingosine kinase 1, suppressed EGF-induced C2C12 activation. We also present the evidence showing the S1P receptor S1P2 is involved in EGF-induced reserve cell activation. Moreover, we demonstrated a combination of insulin and EGF promoted activation of satellite cells on single myofibers in a manner dependent on SPHK and S1P2. Taken together, our observations show that EGF-induced satellite cell activation is mediated by S1P and its receptor. - Highlights: • EGF in combination with insulin induces proliferation of quiescent C2C12 cells. • Sphingosine kinase activity increases when reserve cells are stimulated with EGF. • EGF-induced activation of reserve cells is dependent on sphingosine kinase and ERK. • The S1P receptor S1P2 is involved in EGF-induced reserve cell activation. • EGF-induced reserve cell activation is mediated by S1P and its

  5. Synergistic action of auxin and ethylene on root elongation inhibition is caused by a reduction of epidermal cell length.

    Science.gov (United States)

    Alarcón, M Victoria; Lloret, Pedro G; Salguero, Julio

    2014-01-01

    Auxin and ethylene have been largely reported to reduce root elongation in maize primary root. However the effects of auxin are greater than those caused by ethylene. Although auxin stimulates ethylene biosynthesis through the specific increase of ACC synthase, the auxin inhibitory effect on root elongation is not mediated by the auxin-induced increase of ethylene production. Recently it has been demonstrated that root inhibition by the application of the synthetic auxin NAA (1-naphtalenacetic acid) is increased if combined with the ethylene precursor ACC (1-aminocyclopropane-1-carboxilic acid) when both compounds are applied at very low concentrations.   Root elongation is basically the result of two processes: a) cell divisions in the meristem where meristematic cells continuously generate new cells and b) subsequently polarized growth by elongation along the root axis as cells leave the meristem and enter the root elongation zone. Our results indicate that exogenous auxin reduced both root elongation and epidermal cell length. In a different way, ethylene at very low concentrations only inhibited root elongation without affecting significantly epidermal cell length. However, these concentrations of ethylene increased the inhibitory effect of auxin on root elongation and cell length. Consequently the results support the hypothesis that ethylene acts synergistically with auxin in the regulation of root elongation and that inhibition by both hormones is due, at least partially, to the reduction of cell length in the epidermal layer.

  6. Alpha1beta1 integrin is crucial for accumulation of epidermal T cells and the development of psoriasis.

    Science.gov (United States)

    Conrad, Curdin; Boyman, Onur; Tonel, Giulia; Tun-Kyi, Adrian; Laggner, Ute; de Fougerolles, Antonin; Kotelianski, Victor; Gardner, Humphrey; Nestle, Frank O

    2007-07-01

    Psoriasis is a common T cell-mediated autoimmune inflammatory disease. We show that blocking the interaction of alpha1beta1 integrin (VLA-1) with collagen prevented accumulation of epidermal T cells and immunopathology of psoriasis. Alpha1beta1 integrin, a major collagen-binding surface receptor, was exclusively expressed by epidermal but not dermal T cells. Alpha1beta1-positive T cells showed characteristic surface markers of effector memory cells and contained high levels of interferon-gamma but not interleukin-4. Blockade of alpha1beta1 inhibited migration of T cells into the epidermis in a clinically relevant xenotransplantation model. This was paralleled by a complete inhibition of psoriasis development, comparable to that caused by tumor necrosis factor-alpha blockers. These results define a crucial role for alpha1beta1 in controlling the accumulation of epidermal type 1 polarized effector memory T cells in a common human immunopathology and provide the basis for new strategies in psoriasis treatment focusing on T cell-extracellular matrix interactions.

  7. Distribution and number of epidermal growth factor receptors in skin is related to epithelial cell growth

    DEFF Research Database (Denmark)

    Green, M R; Basketter, D A; Couchman, J R

    1983-01-01

    Epidermal growth factor (EGF), a low-molecular-weight polypeptide (G. Carpenter and S. Cohen, 1979, Annu. Rev. Biochem. 48, 193-216), stimulates the proliferation and keratinisation of cultured embryonic epidermis (S. Cohen, 1965, Dev. Biol. 12, 394-407) and promotes epidermal growth, thickening,...

  8. Effect of epidermal growth factor on the migration of neural stem cells

    Institute of Scientific and Technical Information of China (English)

    Faliang Duan; Guoping Yang; Junwu Wei; Jinglei Wu

    2006-01-01

    BACKGROUND:Recently,researches on neural stem cells(NSCs)are focus on differentiation and migration of stem cells.How to regulate and control differentiation and migration of NSCs based on human wills is still a hot topic.OBJECTIVE:To investigate the effct of epidermal growth factor (EGF) on the migration and proliferation of NSCs and analyze duration of the effect.DESIGN:Contrast study based on cells.SETFING:Department of Neurological Surgery,the First Hospital of Wuhan.MATERIALS:Healthy SD rats aged 13-14 embryonic days.EGF(Sigma Company).METHODS:The experiment was carried out in the Animal Laboratory of Experimental Center Affiliated to the First Hospital of Wuhan from October 2004 to July 2006.NSCs selected from embryonic striatum of rats with 13-14 embryonic days were cultured;7 days later,suspended neural sphere was used to make simple cell suspension and cultured once more.Then,DMEM-F12+20 μg/L EGF was added into culture medium;14 days latar.the rats were divided into experimental group and control group.Rats in the experimental group were cultured with the same medium mentioned above;however, rats in the control group were cultured with only DMEM-F12.Migration of cells was observed under microscope every day.MAIN OUTCOME MEASURES:NSCs migration in both experimental group and control group.RESULTS:Cell spheres in primary culture were NSCs.In addition,14 days later,proliferation of stem cells were observed remarkably in EGF culture.and size of cell sphere was about that of 100 cells.In exparimental group.proliferation of cell sphere was slow down on the 14th culture day,and apophysis was erupted to neighbor cell sphere.Moreover,NSCs migrated from big cell sphere to small cell sphere during 14-17 culture days.and then,cell migration was disappeared at 17 days after culture.In control group.cell migration was not observed.CONCLUSION:EGF can induce proliferation and migration of NSCs during a special time(14-17 days).However,NSCs do not immigrate over the

  9. Analysis of epidermal growth factor signaling in nasal mucosa epithelial cell proliferation involved in chronic rhinosinusitis

    Institute of Scientific and Technical Information of China (English)

    Li Yunchuan; Li Lijuan; Wang Tong; Zang Hongrui; An Yunsong; Li Lifeng; Zhang Junyi

    2014-01-01

    Background Aberrant epithelial repair has been observed in chronic rhinosinusitis (CRS) patients; however,the mechanism of epithelial cell repair regulation is unclear.Epidermal growth factor (EGF) plays an important role in regulating epithelial cell repair in lower airway and may be a critical factor in the remodeling processes of CRS.The objective of our research is to evaluate the differences between CRS and normal subjects and between chronic rhinosinusitis without nasal polys (CRSsNP) and chronic rhinosinusitis with nasal polys (CRSwNP) in the regulation of EGF pathways and the regulating proliferative position of classic Ras/Raf/MEK/ERK pathways.Methods We evaluated the proliferation rates of ethmoidal mucosal cells before and after stimulation with EGF,epidermal growth factor receptor (EGFR) kinase inhibitor AG1478,and extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor PD98059 using MTT assays.We also analyzed the sinonasal epithelial cells collected from control subjects and patients with CRS subtypes CRSsNP and CRSwNP for the expression of ERK1/2,phosphorylated ERK1/2,P21,P15,and P27 using western blotting analyses.Results The proliferation rates of sinonasal epithelial cells before and after EGF stimulation were lower in CRS patients than in the controls.AG1478 or PD98059 inhibitor treatment of control epithelial cells did not result in a significant difference in proliferation.Although,AG1478 and PD98059 inhibited the proliferation of CRS cells,the degree of proliferation inhibition was markedly different in CRSsNP.AG 1478 suppressed the proliferation of CRSwNP epithelial cells,whereas PD98059 had no effect.The ratio of ERK1/2 phosphorylation in CRS cells was lower than that of the control cells.Cyclin-dependent kinase inhibitors were highly expressed in CRS cells compared with that of control cells.ERK1/2 and P27 showed differential expression in CRSsNP and CRSwNP.Conclusions Differences existed in EGF pathways in CRS patients and normal

  10. Effect of glucocorticoid on epidermal growth factor receptor in human salivary gland adenocarcinoma cell line HSG.

    Science.gov (United States)

    Kyakumoto, S; Kurokawa, R; Ota, M

    1990-07-12

    Human salivary gland adenocarcinoma (HSG) cells treated with 10(-6) M triamcinolone acetonide for 48 h exhibited a 1.7- to 2.0-fold increase in [125I]human epidermal growth factor (hEGF) binding capacity as compared with untreated HSG cells. Scatchard analysis of [125I]EGF binding data revealed that the number of binding sites was 83,700 (+/- 29,200) receptors/cell in untreated cells and 160,500 (+/- 35,500) receptors/cell in treated cells. No substantial change in receptor affinity was detected. The dissociation constant of the EGF receptor was 0.78 (+/- 0.26).10(-9) M for untreated cells, whereas it was 0.93 (+/- 0.31).10(-9)M for treated cells. The triamcinolone acetonide-induced increase in [125I]EGF binding capacity was dose-dependent between 10(-9) and 10(-6)M, and maximal binding was observed at 10(-6)M. EGF receptors on HSG cells were affinity-labeled with [125I]EGF by use of the cross-linking reagent disuccinimidyl suberate (DSS). The cross-linked [125I]EGF was 3-4% of the total [125I]EGF bound to HSG cells. The affinity-labeled EGF receptor was detected as a specific 170 kDa band in the autoradiograph after SDS-polyacrylamide gel electrophoresis (SDS-PAGE). Densitometric analysis revealed that triamcinolone acetonide amplified the intensity of this band 2.0-fold over that of the band of untreated cells. EGF receptor synthesis was also measured by immunoprecipitation of [3H]leucine-labeled EGF receptor protein with anti-hEGF receptor monoclonal antibody. Receptor synthesis was increased 1.7- to 1.8-fold when HSG cells were treated with 10(-8)-10(-6)M triamcinolone acetonide for 48 h. When the immunoprecipitated, [35S]methionine-pulse-labeled EGF receptor was analyzed by SDS-PAGE and fluorography, the newly synthesized EGF receptor was detected at the position of 170 kDa; and treatment of HSG cells with triamcinolone acetonide resulted in a 2.0-fold amplification of this 170 kDa band. There was no significant difference in turnover rate of EGF receptor

  11. Eosinophil peroxidase signals via epidermal growth factor-2 to induce cell proliferation.

    LENUS (Irish Health Repository)

    Walsh, Marie-Therese

    2011-11-01

    Eosinophils exert many of their inflammatory effects in allergic disorders through the degranulation and release of intracellular mediators, including a set of cationic granule proteins that include eosinophil peroxidase. Studies suggest that eosinophils are involved in remodeling. In previous studies, we showed that eosinophil granule proteins activate mitogen-activated protein kinase signaling. In this study, we investigated the receptor mediating eosinophil peroxidase-induced signaling and downstream effects. Human cholinergic neuroblastoma IMR32 and murine melanoma B16.F10 cultures, real-time polymerase chain reaction, immunoprecipitations, and Western blotting were used in the study. We showed that eosinophil peroxidase caused a sustained increase in both the expression of epidermal growth factor-2 (HER2) and its phosphorylation at tyrosine 1248, with the consequent activation of extracellular-regulated kinase 1\\/2. This, in turn, promoted a focal adhesion kinase-dependent egress of the cyclin-dependent kinase inhibitor p27(kip) from the nucleus to the cytoplasm. Eosinophil peroxidase induced a HER2-dependent up-regulation of cell proliferation, indicated by an up-regulation of the nuclear proliferation marker Ki67. This study identifies HER2 as a novel mediator of eosinophil peroxidase signaling. The results show that eosinophil peroxidase, at noncytotoxic levels, can drive cell-cycle progression and proliferation, and contribute to tissue remodeling and cell turnover in airway disease. Because eosinophils are a feature of many cancers, these findings also suggest a role for eosinophils in tumorigenesis.

  12. Effects of Arsenic on Cell Proliferation and Its Related Gene Expression in Human Epidermal Keratinocyte

    Institute of Scientific and Technical Information of China (English)

    顾军; 毕新岭; 米庆胜; 文军慧

    2002-01-01

    Objective:To study the effects of low concentration of arsenic (As2O3) on DNA synthesisand related transcription factor gene E2F1 expression in keratinocyte. Methods: Human epidermal kerati-nocyte (cell line HaCaT) cultured in vitro was used. After treatment with various concentrations of arse-nic, DNA synthesis and E2F1 expression in HaCaT cells were detected by using 3 H-TdR method and RT-PCR. Results: Arsenic caused a modest increase of keratinocyte DNA synthesis when the concentrationreached the range within 0.5-16 nmol/L, but the amount of incorporated 3 H-TdR decreased and returnedto baseline level when the concentration of arsenic increased to over 16 nmol/L. RT-PCR analysis showedthe level of E2F1 mRNA was elevated in HaCaT cells with the increase of DNA synthesis. Conclusion:Ar-senic of a certain concentration could increase DNA synthesis and enhance E2F1 expression in HaCaT cellline, which might be one of the pathological mechanisms of skin disease related to arsenic.

  13. Temporal Evolution of the Plasma Sheath Surrounding Solar Cells in Low Earth Orbit

    Science.gov (United States)

    Willis, Emily M.; Pour, Maria Z. A.

    2017-01-01

    High voltage solar array interactions with the space environment can have a significant impact on array performance and spacecraft charging. Over the past 10 years, data from the International Space Station has allowed for detailed observations of these interactions over long periods of time. Some of the surprising observations have been floating potential transients, which were not expected and are not reproduced by existing models. In order to understand the underlying processes producing these transients, the temporal evolution of the plasma sheath surrounding the solar cells in low Earth orbit is being investigated. This study includes lumped element modeling and particle-in-cell simulation methods. This presentation will focus on recent results from the on-going investigations.

  14. Modulation of JB6 Mouse Epidermal Cell Transformation Response by the Prostaglandin F2 Alpha Receptor

    Energy Technology Data Exchange (ETDEWEB)

    Weber, Thomas J.; Markillie, Lye MENG.; Chrisler, William B.; Vielhauer, George A.; Regan, John W.

    2002-12-01

    Prostaglandin F2a (PGF2a) has been associated with the modulation of clonal selection processes in the mouse skin model of carcinogenesis. We have investigated whether JB6 mouse epidermal cells express a functional PGF2a receptor (FP) coupled to the regulation of anchorage-dependent and -independent growth. Treatment of JB6 cells with a FP receptor ligand (fluprostenol) potently (pM-nM) increased anchorage-dependent and -independent growth, as determined by a battery of in vitro assays. Treatment of JB6 cells with PGF2a and fluprostenol increased inositol phospholipid accumulation and extracellular signal regulated kinase (ERK) activity, consistent with FP receptor-related signaling. FP receptor mRNA was detected by reverse transcription-polymerase chain reaction and a radiolabel binding assay determined the average specific [3H]PGF2a binding to be 8.25 + 0.95 fmol/mg protein. Treatment of cells with fluprostenol as a single exposure resulted in a significant increase in anchorage-dependent and -independent growth in media containing low (0.1-0.5%), but not high (5%) concentrations of fetal bovine serum (FBS). In contrast, treatment of cells with fluprostenol at two day intervals resulted in a more robust growth response under anchorage-dependent conditions only in media containing low FBS concentrations; and under anchorage-independent conditions only in media containing high FBS concentrations. ERK activation and colony size were increased by cotreatment of JB6 cells with EGF and fluprostenol to a greater extent than either treatment alone, while the cotreatment effect on colony number appeared to be simply additive. In summary, FBS concentration and signal oscillation exert pronounced effects on the biological response to a FP receptor agonist. The data raise the possibility that the FP receptor may independently contribute to clonal selection processes, but may play a more important role as a response modifier.

  15. Extended C termini of CPC-LIKE MYB proteins confer functional diversity in Arabidopsis epidermal cell differentiation.

    Science.gov (United States)

    Tominaga-Wada, Rumi; Wada, Takuji

    2017-07-01

    The CAPRICE (CPC) gene encodes a R3-type MYB transcription factor that promotes differentiation of root hair cells in Arabidopsis thaliana Here, we have compared the functions of five CPC-homologous genes for epidermal cell differentiation using CPC promoter-driven transgenic plants. Our results show that TRIPTYCHON (TRY) and ENHANCER OF TRY AND CPC2 (ETC2) were less effective in root hair cell differentiation and were unstable in root epidermal cells when compared with CPC, ETC1 or CPC LIKE MYB3 (CPL3). The deletion of the extended C-terminal domain of TRY and ETC2 enhanced protein stability and conferred the ability to induce root hair cell differentiation on them. Treatment with MG132, a proteasome inhibitor, also led to the accumulation of TRY, indicating that TRY proteolysis is mediated by the proteasome-dependent pathway. Our results indicate that the CPC family includes relatively stable (CPC, ETC1 and CPL3) and unstable (TRY and ETC2) proteins that might be degraded by the proteasome. Our findings provide new insights into the regulatory mechanism of CPC family proteins that mediate root hair cell differentiation and should be useful in understanding epidermal development. © 2017. Published by The Company of Biologists Ltd.

  16. Bizonoplast, a unique chloroplast in the epidermal cells of microphylls in the shade plant Selaginella erythropus (Selaginellaceae).

    Science.gov (United States)

    Sheue, Chiou-Rong; Sarafis, Vassilios; Kiew, Ruth; Liu, Ho-Yih; Salino, Alexandre; Kuo-Huang, Ling-Long; Yang, Yuen-Po; Tsai, Chi-Chu; Lin, Chun-Hung; Yong, Jean W H; Ku, Maurice S B

    2007-12-01

    Study of the unique leaf anatomy and chloroplast structure in shade-adapted plants will aid our understanding of how plants use light efficiently in low light environments. Unusual chloroplasts in terms of size and thylakoid membrane stacking have been described previously in several deep-shade plants. In this study, a single giant cup-shaped chloroplast, termed a bizonoplast, was found in the abaxial epidermal cells of the dorsal microphylls and the adaxial epidermal cells of the ventral microphylls in the deep-shade spike moss Selaginella erythropus. Bizonoplasts are dimorphic in ultrastructure: the upper zone is occupied by numerous layers of 2-4 stacked thylakoid membranes while the lower zone contains both unstacked stromal thylakoids and thylakoid lamellae stacked in normal grana structure oriented in different directions. In contrast, other cell types in the microphylls contain chloroplasts with typical structure. This unique chloroplast has not been reported from any other species. The enlargement of epidermal cells into funnel-shaped, photosynthetic cells coupled with specific localization of a large bizonoplast in the lower part of the cells and differential modification in ultrastructure within the chloroplast may allow the plant to better adapt to low light. Further experiments are required to determine whether this shade-adapted organism derives any evolutionary or ecophysiological fitness from these unique chloroplasts.

  17. Preparation of Epidermal Peels and Guard Cell Protoplasts for Cellular, Electrophysiological, and -Omics Assays of Guard Cell Function.

    Science.gov (United States)

    Zhu, Mengmeng; Jeon, Byeong Wook; Geng, Sisi; Yu, Yunqing; Balmant, Kelly; Chen, Sixue; Assmann, Sarah M

    2016-01-01

    Bioassays are commonly used to study stomatal phenotypes. There are multiple options in the choice of plant materials and species used for observation of stomatal and guard cell responses in vivo. Here, detailed procedures for bioassays of stomatal responses to abscisic acid (ABA) in Arabidopsis thaliana are described, including ABA promotion of stomatal closure, ABA inhibition of stomatal opening, and ABA promotion of reaction oxygen species (ROS) production in guard cells. We also include an example of a stomatal bioassay for the guard cell CO2 response using guard cell-enriched epidermal peels from Brassica napus. Highly pure preparations of guard cell protoplasts can be produced, which are also suitable for studies on guard cell signaling, as well as for studies on guard cell ion transport. Small-scale and large-scale guard cell protoplast preparations are commonly used for electrophysiological and -omics studies, respectively. We provide a procedure for small-scale guard cell protoplasting from A. thaliana. Additionally, a general protocol for large-scale preparation of guard cell protoplasts, with specifications for three different species, A. thaliana, B. napus, and Vicia faba is also provided.

  18. IgG and IgA with Potential Microbial-Binding Activity Are Expressed by Normal Human Skin Epidermal Cells

    Directory of Open Access Journals (Sweden)

    Dongyang Jiang

    2015-01-01

    Full Text Available The innate immune system of the skin is thought to depend largely on a multi-layered mechanical barrier supplemented by epidermis-derived antimicrobial peptides. To date, there are no reports of antimicrobial antibody secretion by the epidermis. In this study, we report the expression of functional immunoglobulin G (IgG and immunoglobulin A (IgA, previously thought to be only produced by B cells, in normal human epidermal cells and the human keratinocyte line HaCaT. While B cells express a fully diverse Ig, epidermal cell-expressed IgG or IgA showed one or two conservative VHDJH rearrangements in each individual. These unique VDJ rearrangements in epidermal cells were found neither in the B cell-derived Ig VDJ databases published by others nor in our positive controls. IgG and IgA from epidermal cells of the same individual had different VDJ rearrangement patterns. IgG was found primarily in prickle cells, and IgA was mainly detected in basal cells. Both epidermal cell-derived IgG and IgA showed potential antibody activity by binding pathogens like Staphylococcus aureus, the most common pathogenic skin bacteria, but the microbial-binding profile was different. Our data indicates that normal human epidermal cells spontaneously express IgG and IgA, and we speculate that these Igs participate in skin innate immunity.

  19. Transient silencing of CHALCONE SYNTHASE during fruit ripening modifies tomato epidermal cells and cuticle properties.

    Science.gov (United States)

    España, Laura; Heredia-Guerrero, José A; Reina-Pinto, José J; Fernández-Muñoz, Rafael; Heredia, Antonio; Domínguez, Eva

    2014-11-01

    Tomato (Solanum lycopersicum) fruit ripening is accompanied by an increase in CHALCONE SYNTHASE (CHS) activity and flavonoid biosynthesis. Flavonoids accumulate in the cuticle, giving its characteristic orange color that contributes to the eventual red color of the ripe fruit. Using virus-induced gene silencing in fruits, we have down-regulated the expression of SlCHS during ripening and compared the cuticles derived from silenced and nonsilenced regions. Silenced regions showed a pink color due to the lack of flavonoids incorporated to the cuticle. This change in color was accompanied by several other changes in the cuticle and epidermis. The epidermal cells displayed a decreased tangential cell width; a decrease in the amount of cuticle and its main components, cutin and polysaccharides, was also observed. Flavonoids dramatically altered the cuticle biomechanical properties by stiffening the elastic and viscoelastic phase and by reducing the ability of the cuticle to deform. There seemed to be a negative relation between SlCHS expression and wax accumulation during ripening that could be related to the decreased cuticle permeability to water observed in the regions silencing SlCHS. A reduction in the overall number of ester linkages present in the cutin matrix was also dependent on the presence of flavonoids.

  20. Dysregulation of epidermal growth factor receptor in actinic keratosis and squamous cell carcinoma.

    Science.gov (United States)

    Joseph, Shannon R; Endo-Munoz, Liliana; Gaffney, Daniel C; Saunders, Nicholas A; Simpson, Fiona

    2015-01-01

    The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase. Its correct function is required for normal skin development and homeostasis, while dysregulation of EGFR signalling results in cellular hyper-proliferation and defects in differentiation, leading to impaired wound healing, the development of psoriasis-like lesions, structural and functional defects of hair follicles and tumourigenesis. Actinic keratosis, which is also known as solar keratosis, develops in sun-exposed areas of the skin. These are often called 'premalignant lesions' and are said to represent early squamous cell carcinoma (SCC) in situ, although debate over their classification continues. Anti-EGFR therapies have been approved for the treatment of several malignancies and are undergoing trials for others [1], including advanced cutaneous squamous cell carcinoma (CSCC). However, a number of questions remain regarding the treatment of CSCC with anti-EGFR inhibitors. A lower number of CSCC tumours are EGFR positive in comparison to other types of tumours, such as head and neck SCC (HNSCC), and it has been suggested that patients should be selected on the basis of high tumour EGFR expression. However, there are reports of patients with tumours showing no EGFR-positive staining responding to anti-EGFR therapy. EGFR is an oncogenic driver in many tumours. Does it drive the transformation of actinic keratosis to a tumourigenic phenotype? Many such questions remain, and here, we discuss the role of EGFR in SCC and its functions during the different stages of skin cancer development. © 2015 S. Karger AG, Basel.

  1. Microenvironmental stiffness enhances glioma cell proliferation by stimulating epidermal growth factor receptor signaling.

    Directory of Open Access Journals (Sweden)

    Vaibhavi Umesh

    Full Text Available The aggressive and rapidly lethal brain tumor glioblastoma (GBM is associated with profound tissue stiffening and genomic lesions in key members of the epidermal growth factor receptor (EGFR pathway. Previous studies from our laboratory have shown that increasing microenvironmental stiffness in culture can strongly enhance glioma cell behaviors relevant to tumor progression, including proliferation, yet it has remained unclear whether stiffness and EGFR regulate proliferation through common or independent signaling mechanisms. Here we test the hypothesis that microenvironmental stiffness regulates cell cycle progression and proliferation in GBM tumor cells by altering EGFR-dependent signaling. We began by performing an unbiased reverse phase protein array screen, which revealed that stiffness modulates expression and phosphorylation of a broad range of signals relevant to proliferation, including members of the EGFR pathway. We subsequently found that culturing human GBM tumor cells on progressively stiffer culture substrates both dramatically increases proliferation and facilitates passage through the G1/S checkpoint of the cell cycle, consistent with an EGFR-dependent process. Western Blots showed that increasing microenvironmental stiffness enhances the expression and phosphorylation of EGFR and its downstream effector Akt. Pharmacological loss-of-function studies revealed that the stiffness-sensitivity of proliferation is strongly blunted by inhibition of EGFR, Akt, or PI3 kinase. Finally, we observed that stiffness strongly regulates EGFR clustering, with phosphorylated EGFR condensing into vinculin-positive focal adhesions on stiff substrates and dispersing as microenvironmental stiffness falls to physiological levels. Our findings collectively support a model in which tissue stiffening promotes GBM proliferation by spatially and biochemically amplifying EGFR signaling.

  2. Mediated exodus of L-dopa from human epidermal Langerhans cells.

    Science.gov (United States)

    Falck, B; Bendsoe, N; Ronquist, G

    2004-03-01

    L-3,4-dihydroxyphenylalanine (L-dopa) is not metabolized within human epidermal Langerhans cells (LC); yet they can take up substantial amounts of this amino acid which subsequently can be released into the extracellular space. We recently reported that human epidermal energy metabolism is predominantly anaerobic and that the influx mechanism is a unidirectional L-dopa/proton counter-transport system and now we describe conditions for the mediated transport of L-dopa out of the LC. It is demonstrated that certain amino acids and one dipeptide can effectively trigger the efflux of L-dopa taken up by the LC.Thus, alpha-methyl-dopa (alpha-m-dopa), D-dopa and the dipeptide, met-ala at the outside of the plasma membrane stimulated the efflux of L-dopa from L-dopa loaded LC. Similar effects were achieved by a variety of other amino acids in the extracellular fluid while some other amino acids were inactive. The time required for 50% D-methionine-induced exodus of L-dopa from L-dopa loaded LC was in the range of 5-7 min and a complete exodus of L-dopa was attained at about 20 min of incubation. This dislocation of L-dopa to the extracellular fluid is interpreted as an expression of trans-stimulation. In the case of alpha-m-dopa, D-dopa and met-ala, which admittedly were not able to penetrate the plasma membrane of LC, the concept of trans-stimulation was given a new purport, since none of them were able to participate in an exchange reaction. Finally, it could be concluded that L-dopa escaped by a route different from the one responsible for L-dopa uptake in LC.Thus, while the influx of L-dopa supports extrusion of protons deriving from anaerobic glycolysis in the LC, L-dopa efflux can provide the cells with useful amino acids in an energy-saving way, altogether a remarkable biological process. From this follows that L-dopa has a biological function of its own, besides being a precursor in the catecholamine and pigment syntheses.

  3. The influence of stromal cells on the pigmentation of tissue-engineered dermo-epidermal skin grafts.

    Science.gov (United States)

    Biedermann, Thomas; Böttcher-Haberzeth, Sophie; Klar, Agnieszka S; Widmer, Daniel S; Pontiggia, Luca; Weber, Andreas D; Weber, Daniel M; Schiestl, Clemens; Meuli, Martin; Reichmann, Ernst

    2015-03-01

    It has been shown in vitro that melanocyte proliferation and function in palmoplantar skin is regulated by mesenchymal factors derived from fibroblasts. In this study, we investigated in vivo the influence of mesenchymal-epithelial interactions in human tissue-engineered skin substitutes reconstructed from palmar- and nonpalmoplantar-derived fibroblasts. Tissue-engineered dermo-epidermal analogs based on collagen type I hydrogels were populated with either human palmar or nonpalmoplantar fibroblasts and seeded with human nonpalmoplantar-derived melanocytes and keratinocytes. These skin substitutes were transplanted onto full-thickness skin wounds of immunoincompetent rats. Four weeks after transplantation the development of skin color was measured and grafts were excised and analyzed with regard to epidermal characteristics, in particular melanocyte number and function. Skin substitutes containing palmar-derived fibroblasts in comparison to nonpalmoplantar-derived fibroblasts showed (a) a significantly lighter pigmentation; (b) a reduced amount of epidermal melanin granules; and (c) a distinct melanosome expression. However, the number of melanocytes in the basal layer remained similar in both transplantation groups. These findings demonstrate that human palmar fibroblasts regulate the function of melanocytes in human pigmented dermo-epidermal skin substitutes after transplantation, whereas the number of melanocytes remains constant. This underscores the influence of site-specific stromal cells and their importance when constructing skin substitutes for clinical application.

  4. Photodynamic injury of isolated crayfish neuron and surrounding glial cells: the role of p53

    Science.gov (United States)

    Sharifulina, S. A.; Uzdensky, A. B.

    2015-03-01

    The pro-apoptotic transcription factor p53 is involved in cell responses to injurious impacts. Using its inhibitor pifithrin- α and activators tenovin-1, RITA and WR-1065, we studied its potential participation in inactivation and death of isolated crayfish mechanoreceptor neuron and satellite glial cells induced by photodynamic treatment, a strong inducer of oxidative stress. In dark, p53 activation by tenovin-1 or WR-1065 shortened activity of isolated neurons. Tenovin-1 and WR-1065 induced apoptosis of glial cells, whereas pifithrin-α was anti-apoptotic. Therefore, p53 mediated glial apoptosis and suppression of neuronal activity after axotomy. Tenovin-1 but not other p53 modulators induced necrosis of axotomized neurons and surrounding glia, possibly, through p53-independent pathway. Under photodynamic treatment, p53 activators tenovin-1 and RITA enhanced glial apoptosis indicating the pro-apoptotic activity of p53. Photoinduced necrosis of neurons and glia was suppressed by tenovin-1 and, paradoxically, by pifithrin-α. Modulation of photoinduced changes in the neuronal activity and necrosis of neurons and glia was possibly p53-independent. The different effects of p53 modulators on neuronal and glial responses to axotomy and photodynamic impact were apparently associated with different signaling pathways in neurons and glial cells.

  5. RhoA promotes epidermal stem cell proliferation via PKN1-cyclin D1 signaling

    Science.gov (United States)

    Wang, Fan; Zhan, Rixing; Chen, Liang; Dai, Xia; Wang, Wenping; Guo, Rui; Li, Xiaoge; Li, Zhe; Wang, Liang; Huang, Shupeng; Shen, Jie

    2017-01-01

    Objective Epidermal stem cells (ESCs) play a critical role in wound healing, but the mechanism underlying ESC proliferation is not well defined. Here, we explore the effects of RhoA on ESC proliferation and the possible underlying mechanism. Methods Human ESCs were enriched by rapid adhesion to collagen IV. RhoA(+/+)(G14V), RhoA(-/-)(T19N) and pGFP control plasmids were transfected into human ESCs. The effect of RhoA on cell proliferation was detected by cell proliferation and DNA synthesis assays. Induction of PKN1 activity by RhoA was determined by immunoblot analysis, and the effects of PKN1 on RhoA in terms of inducing cell proliferation and cyclin D1 expression were detected using specific siRNA targeting PKN1. The effects of U-46619 (a RhoA agonist) and C3 transferase (a RhoA antagonist) on ESC proliferation were observed in vivo. Results RhoA had a positive effect on ESC proliferation, and PKN1 activity was up-regulated by the active RhoA mutant (G14V) and suppressed by RhoA T19N. Moreover, the ability of RhoA to promote ESC proliferation and DNA synthesis was interrupted by PKN1 siRNA. Additionally, cyclin D1 protein and mRNA expression levels were up-regulated by RhoA G14V, and these effects were inhibited by siRNA-mediated knock-down of PKN1. RhoA also promoted ESC proliferation via PKN in vivo. Conclusion This study shows that the effect of RhoA on ESC proliferation is mediated by activation of the PKN1-cyclin D1 pathway in vitro, suggesting that RhoA may serve as a new therapeutic target for wound healing. PMID:28222172

  6. Stringent control of cytoplasmic Ca2+ in guard cells of intact plants compared to their counterparts in epidermal strips or guard cell protoplasts.

    Science.gov (United States)

    Levchenko, V; Guinot, D R; Klein, M; Roelfsema, M R G; Hedrich, R; Dietrich, P

    2008-01-01

    Cytoplasmic calcium elevations, transients, and oscillations are thought to encode information that triggers a variety of physiological responses in plant cells. Yet Ca(2+) signals induced by a single stimulus vary, depending on the physiological state of the cell and experimental conditions. We compared Ca(2+) homeostasis and stimulus-induced Ca(2+) signals in guard cells of intact plants, epidermal strips, and isolated protoplasts. Single-cell ratiometric imaging with the Ca(2+)-sensitive dye Fura 2 was applied in combination with electrophysiological recordings. Guard cell protoplasts were loaded with Fura 2 via a patch pipette, revealing a cytoplasmic free Ca(2+) concentration of around 80 nM at -47 mV. Upon hyperpolarization of the plasma membrane to -107 mV, the Ca(2+) concentration increased to levels exceeding 400 nM. Intact guard cells were able to maintain much lower cytoplasmic free Ca(2+) concentrations at hyperpolarized potentials, the average concentration at -100 mV was 183 and 90 nM in epidermal strips and intact plants, respectively. Further hyperpolarization of the plasma membrane to -160 mV induced a sustained rise of the guard cell cytoplasmic Ca(2+) concentration, which slowly returned to the prestimulus level in intact plants but not in epidermal strips. Our results show that cytoplasmic Ca(2+) concentrations are stringently controlled in guard cells of intact plants but become increasingly more sensitive to changes in the plasma membrane potential in epidermal strips and isolated protoplasts.

  7. Comparative SAXS and DSC study on stratum corneum structural organization in an epidermal cell culture model (ROC)

    DEFF Research Database (Denmark)

    Kuntsche, Judith; Herre, Angela; Fahr, Alfred

    2013-01-01

    Cell cultured skin equivalents present an alternative for dermatological in vitro evaluations of drugs and excipients as they provide the advantage of availability, lower variability and higher assay robustness compared to native skin. For penetration/permeation studies, an adequate stratum corneum...... barrier similar to that of human stratum corneum is, however, a prerequisite. In this study, the stratum corneum lipid organization in an epidermal cell culture model based on rat epidermal keratinocytes (REK organotypic culture, ROC) was investigated by small-angle X-ray scattering (SAXS) in dependence...... of ROC SC obtained at different cultivation times (7, 14 and 21days at the air-liquid interface) was connected with an increase in structural order of the SC lipids in SAXS measurements: Already cultivation for 14days at the air-liquid interface resulted overall in a competent SC permeability barrier...

  8. Biological activity of the bryostatin analog Merle 23 on mouse epidermal cells and mouse skin.

    Science.gov (United States)

    Kelsey, Jessica S; Cataisson, Christophe; Chen, Jinqiu; Herrmann, Michelle A; Petersen, Mark E; Baumann, David O; McGowan, Kevin M; Yuspa, Stuart H; Keck, Gary E; Blumberg, Peter M

    2016-12-01

    Bryostatin 1, a complex macrocyclic lactone, is the subject of multiple clinical trials for cancer chemotherapy. Although bryostatin 1 biochemically functions like the classic mouse skin tumor promoter phorbol 12-myristate 13-acetate (PMA) to bind to and activate protein kinase C, paradoxically, it fails to induce many of the typical phorbol ester responses, including tumor promotion. Intense synthetic efforts are currently underway to develop simplified bryostatin analogs that preserve the critical functional features of bryostatin 1, including its lack of tumor promoting activity. The degree to which bryostatin analogs maintain the unique pattern of biological behavior of bryostatin 1 depends on the specific cellular system and the specific response. Merle 23 is a significantly simplified bryostatin analog that retains bryostatin like activity only to a limited extent. Here, we show that in mouse epidermal cells the activity of Merle 23 was either similar to bryostatin 1 or intermediate between bryostatin 1 and PMA, depending on the specific parameter examined. We then examined the hyperplastic and tumor promoting activity of Merle 23 on mouse skin. Merle 23 showed substantially reduced hyperplasia and was not tumor promoting at a dose comparable to that for PMA. These results suggest that there may be substantial flexibility in the design of bryostatin analogs that retain its lack of tumor promoting activity. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. Blue-light-induced rapid chloroplast de-anchoring in Vallisneria epidermal cells

    Institute of Scientific and Technical Information of China (English)

    Yuuki Sakai; Shin-Ichiro Inoue; Akiko Harada; Ken-Ichiro Shimazaki; Shingo Takagi

    2015-01-01

    In the outer periclinal cytoplasm of leaf epidermal cells of an aquatic angiosperm Vallisneria, blue light induces “chloroplast de‐anchoring”, a rapid decline in the resistance of chloroplasts against centrifugal force. Chloroplast deanchoring is known induced within 1 min of irradiation with high‐fluence‐rate blue light specifically, preceding the commencement of chloroplasts migration toward the anticlinal cytoplasm. However, its regulatory mechanism has remained elusive, although pharmacological analysis suggested that a calcium release from intracellular calcium stores is necessary for the response. In search of the responsible photoreceptors, immunoblotting analysis using antibodies against phototropins demonstrated that cross‐reactive polypeptides of 120‐kDa exist in the plasma‐membrane fraction prepared from the leaves. In vitro phosphorylation analysis revealed that 120‐kDa polypeptides were phosphorylated by exposure to blue light in a fluence‐dependent manner. The blue‐light‐induced phosphorylation activity was sensitive to a Ser/Thr kinase inhibitor, staurosporine, and unusually was retained at a high level for a long time in darkness. Furthermore, phototropin gene homologs (Vallisneria PHOTOTROPIN1 and PHOTOTROPIN2) expressed in leaves were isolated. We propose that calciumregulated chloroplast de‐anchoring, possibly mediated by phototropins, is an initial process of the blue‐light‐induced avoidance response of chloroplasts in Vallisneria.

  10. Resistance to Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors in Non-Small Cell Lung Cancer.

    Science.gov (United States)

    Hammerman, Peter S; Jänne, Pasi A; Johnson, Bruce E

    2009-12-15

    Gefitinib and erlotinib are ATP competitive inhibitors of the epidermal growth factor receptor (EGFR) tyrosine kinase and are approved around the world for the treatment of patients with non-small cell lung cancer (NSCLC). Somatic mutations in the EGFR are found in 10 to 40% of patients with NSCLC. Patients with sensitizing somatic mutations of EGFR treated with gefitinib or erlotinib have an initial clinical response of 60 to 80%, approximately twice as high as the responses associated with the administration of conventional platinum-based chemotherapy. However, the efficacy of EGFR tyrosine kinase inhibitors (TKI) is limited by either primary (de novo) or acquired resistance after therapy and investigations to define the mechanisms of resistance are active areas of ongoing preclinical and clinical studies. Primary resistance is typically caused by other somatic mutations in genes such as KRAS, which also have an impact on the EGFR signaling pathway or by mutations in the EGFR gene that are not associated with sensitivity to EGFR-TKIs. Two established mechanisms of acquired resistance are caused by additional mutations in the EGFR gene acquired during the course of treatment that change the protein-coding sequence or by amplification of another oncogene signaling pathway driven by the MET oncogene. This review focuses on characterized mechanisms of resistance to the EGFR TKIs and efforts to overcome the problem of resistance aimed at improving the therapy of patients with NSCLC. (Clin Cancer Res 2009;15(24):7502-9).

  11. Surface composition gradients of immobilized cell signaling molecules. Epidermal growth factor on gold

    Energy Technology Data Exchange (ETDEWEB)

    Wang Qian [Department of Chemistry and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL 61801 (United States); Bohn, Paul W. [Department of Chemistry and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL 61801 (United States)]. E-mail: bohn@scs.uiuc.edu

    2006-08-14

    Surface composition gradients of the signaling molecule, epidermal growth factor (EGF), have been prepared by an adaptation of the electrochemical gradient technique. EGF is covalently bound to the reactive component, 11-amino-l-undecanethiol (AUT), in a counterpropagating two-component gradient composed of AUT and poly(ethylene glycol) thiol (PEG) using carbodiimide coupling chemistry. Areas of the surface presenting -NH{sub 2} termination react with succinimidyl esters of solvent-accessible acidic amino acids in EGF, while non-specific protein adsorption is resisted in the PEG regions. The maximum surface coverage of EGF prepared in this manner was determined by surface plasmon resonance reflectometry (SPR) on spatially uniform films to be 20% < {gamma} {sub EGF} < 70% depending on the concentration of the EGF derivatization solution. EGF retains its biological activity with this immobilization process, as verified by culturing human umbilical vein endothelial cell (HUVEC) on an EGF-terminated surface for 24 h. PEG shows good resistance to EGF physical adsorption as demonstrated by both SPR and X-ray photoelectron spectroscopy (XPS). The N / C ratio of EGF gradients, which is characteristic of EGF adsorption, because only the protein contains N, while both protein and PEG contain C, was spatially mapped with XPS. The gradient composition distributions are sigmoidal with lateral distance, with the position of the gradient transition region being readily controlled by adjusting the applied potential window. EGF gradients with variable quantitative surface coverage profiles were generated by varying EGF and AUT concentrations.

  12. Regulation of epidermal cell interleukin-6 production by UV light and corticosteroids

    Energy Technology Data Exchange (ETDEWEB)

    Kirnbauer, R.; Koeck, A.N.; Neuner, P.; Foerster, E.K.; Krutmann, J.; Urbanski, A.; Schauer, E.; Ansel, J.C.; Schwarz, T.; Luger, T.A. (Univ. of Vienna (Austria))

    1991-04-01

    Epidermal cells (EC) are well known as a source of cytokines, including interleukin (IL)-6. In the present study, we investigated whether ultraviolet (UV) light and corticosteroids (CS) affect IL-6 production by normal (HNK) or malignant (KB) human keratinocytes. Supernatants derived from UVB (100 J/m2)- but not from UVA (100-1500 kJ/m2)-exposed EC (HNK and KB) contained significantly increased levels of IL-6 activity. This was also confirmed by Western blot analysis, resulting in specific bands at 23 kD and 27 kD. Northern blot analysis revealed an enhanced IL-6 mRNA expression after UVB exposure. Addition of hydrocortisone, prednisolone, or dexamethasone immediately after UVB irradiation significantly blocked UVB or IL-1-induced IL-6 mRNA expression and production by EC. The suppressive effect was observed at doses in the physiologic (10(-7)-10(-9) M) as well as pharmacologic (10(-5)-10(-7) M) range. In contrast, the nonactive steroid prednisone did not affect EC IL-6 mRNA expression. These findings indicate that increased IL-6 production by EC after UVB irradiation may mediate local and systemic inflammatory reactions following extensive sun exposure. Thus, the therapeutic effect of corticosteroids observed in various inflammatory diseases may be partly due to their downregulating capacity of IL-6 production.

  13. Detecting the epidermal growth factor receptors status in non-small cell lung cancer

    Institute of Scientific and Technical Information of China (English)

    MENG Xue; YU Jin-ming

    2011-01-01

    Non-small cell lung cancer is one of the leading causes of all cancer deaths,but despite years of research,it is still difficult to predict the response and clinical outcome of the disease.In recent years,new treatment strategies targeting the epidermal growth factor receptors (EGFR) have been developed.EGFR is one of the most frequently over expressed proteins in various cancers,including lung cancer,and signaling through this receptor has been known to cause tumor progression as well as resistance to different treatments.Therefore,EGFR has become an attractive target for various treatment strategies.However,it is important to note that not all patients with lung cancer are suitable for targeted treatment,and that patients should be selected for this treatment.Several studies have proven that the status of the EGFR can be both an indicator of suitability for treatment with,and predict the likelihood of response to EGFR targeted therapy.There are many standard techniques to be used for the detection of EGFR.This overview summarizes the ongoing and future investigations to determine the status of the EGFR.

  14. Specific epidermal growth factor receptor autophosphorylation sites promote mouse colon epithelial cell chemotaxis and restitution.

    Science.gov (United States)

    Yamaoka, Toshimitsu; Frey, Mark R; Dise, Rebecca S; Bernard, Jessica K; Polk, D Brent

    2011-08-01

    Upon ligand binding, epidermal growth factor (EGF) receptor (R) autophosphorylates on COOH-terminal tyrosines, generating docking sites for signaling partners that stimulate proliferation, restitution, and chemotaxis. Specificity for individual EGFR tyrosines in cellular responses has been hypothesized but not well documented. Here we tested the requirement for particular tyrosines, and associated downstream pathways, in mouse colon epithelial cell chemotactic migration. We compared these requirements to those for the phenotypically distinct restitution (wound healing) migration. Wild-type, Y992/1173F, Y1045F, Y1068F, and Y1086F EGFR constructs were expressed in EGFR(-/-) cells; EGF-induced chemotaxis or restitution were determined by Boyden chamber or modified scratch wound assay, respectively. Pharmacological inhibitors of p38, phospholipase C (PLC), Src, MEK, JNK/SAPK, phosphatidylinositol 3-kinase (PI 3-kinase), and protein kinase C (PKC) were used to block EGF-stimulated signaling. Pathway activation was determined by immunoblot analysis. Unlike wild-type EGFR, Y992/1173F and Y1086F EGFR did not stimulate colon epithelial cell chemotaxis toward EGF; Y1045F and Y1068F EGFR partially stimulated chemotaxis. Only wild-type EGFR promoted colonocyte restitution. Inhibition of p38, PLC, and Src, or Grb2 knockdown, blocked chemotaxis; JNK, PI 3-kinase, and PKC inhibitors or c-Cbl knockdown blocked restitution but not chemotaxis. All four EGFR mutants stimulated downstream signaling in response to EGF, but Y992/1173F EGFR was partially defective in PLCγ activation whereas both Y1068F and Y1086F EGFR failed to activate Src. We conclude that specific EGFR tyrosines play key roles in determining cellular responses to ligand. Chemotaxis and restitution, which have different migration phenotypes and physiological consequences, have overlapping but not identical EGFR signaling requirements.

  15. Maximum geometrical hindrance to diffusion in brain extracellular space surrounding uniformly spaced convex cells.

    Science.gov (United States)

    Tao, L; Nicholson, C

    2004-07-07

    Brain extracellular space (ECS) constitutes a porous medium in which diffusion is subject to hindrance, described by tortuosity, lambda = (D/D*)1/2, where D is the free diffusion coefficient and D* is the effective diffusion coefficient in brain. Experiments show that lambda is typically 1.6 in normal brain tissue although variations occur in specialized brain regions. In contrast, different theoretical models of cellular assemblies give ambiguous results: they either predict lambda-values similar to experimental data or indicate values of about 1.2. Here we constructed three different ECS geometries involving tens of thousands of cells and performed Monte Carlo simulation of 3-D diffusion. We conclude that the geometrical hindrance in the ECS surrounding uniformly spaced convex cells is independent of the cell shape and only depends on the volume fraction alpha (the ratio of the ECS volume to the whole tissue volume). This dependence can be described by the relation lambda = ((3-alpha)/2)1/2, indicating that the geometrical hindrance in such ECS cannot account for lambda > 1.225. Reasons for the discrepancy between the theoretical and experimental tortuosity values are discussed.

  16. Hair Follicle and Sebaceous Gland De Novo Regeneration With Cultured Epidermal Stem Cells and Skin-Derived Precursors.

    Science.gov (United States)

    Wang, Xiaoxiao; Wang, Xusheng; Liu, Jianjun; Cai, Ting; Guo, Ling; Wang, Shujuan; Wang, Jinmei; Cao, Yanpei; Ge, Jianfeng; Jiang, Yuyang; Tredget, Edward E; Cao, Mengjun; Wu, Yaojiong

    2016-12-01

    : Stem cell-based organ regeneration is purported to enable the replacement of impaired organs in the foreseeable future. Here, we demonstrated that a combination of cultured epidermal stem cells (Epi-SCs) derived from the epidermis and skin-derived precursors (SKPs) was capable of reconstituting functional hair follicles and sebaceous glands (SG). When Epi-SCs and SKPs were mixed in a hydrogel and implanted into an excisional wound in nude mice, the Epi-SCs formed de novo epidermis along with hair follicles, and SKPs contributed to dermal papilla in the neogenic hair follicles. Notably, a combination of culture-expanded Epi-SCs and SKPs derived from the adult human scalp were sufficient to generate hair follicles and hair. Bone morphogenetic protein 4, but not Wnts, sustained the expression of alkaline phosphatase in SKPs in vitro and the hair follicle-inductive property in vivo when SKPs were engrafted with neonatal epidermal cells into excisional wounds. In addition, Epi-SCs were capable of differentiating into sebocytes and formed de novo SGs, which excreted lipids as do normal SGs. Thus our results indicate that cultured Epi-SCs and SKPs are sufficient to generate de novo hair follicles and SGs, implying great potential to develop novel bioengineered skin substitutes with appendage genesis capacity. In postpartum humans, skin appendages lost in injury are not regenerated, despite the considerable achievement made in skin bioengineering. In this study, transplantation of a combination of culture-expanded epidermal stem cells and skin-derived progenitors from mice and adult humans led to de novo regeneration of functional hair follicles and sebaceous glands. The data provide transferable knowledge for the development of novel bioengineered skin substitutes with epidermal appendage regeneration capacity. ©AlphaMed Press.

  17. EGF receptor signaling blocks aryl hydrocarbon receptor-mediated transcription and cell differentiation in human epidermal keratinocytes

    OpenAIRE

    Sutter, Carrie Hayes; Yin, Hong; Li, Yunbo; Mammen, Jennifer S.; Bodreddigari, Sridevi; Stevens, Gaylene; Cole, Judith A; Sutter, Thomas R.

    2009-01-01

    Dioxin is an extremely potent carcinogen. In highly exposed people, the most commonly observed toxicity is chloracne, a pathological response of the skin. Most of the effects of dioxin are attributed to its activation of the aryl hydrocarbon receptor (AHR), a transcription factor that binds to the Ah receptor nuclear translocator (ARNT) to regulate the transcription of numerous genes, including CYP1A1 and CYP1B1. In cultures of normal human epidermal keratinocytes dioxin accelerates cell diff...

  18. siRNA epidermal growth factor receptor silencing in U251 glioma cells

    Institute of Scientific and Technical Information of China (English)

    Chunsheng Kang; Zhiyong Zhang; Zhifan Jia; Qiang Huang; Guangxiu Wang; Mingzhe Qiu; Peiyu Pu

    2008-01-01

    BACKGROUND: Dicer, a large multidomain ribonuclease, is responsible for processing double-stranded RNAs (dsRNAs) to 20-bp-long small interfering RNAs (siRNAs), which act as effectors during RNA interference (RNAi). OBJECTIVE: To observe the efficacy of siRNA cocktails generated by recombinant human Dicer on the down-regulation of epidermal growth factor receptor (EGFR) expression in human glioma cells. DESIGN, TIME AND SETTING: The following in vitro experiment was performed at the Department of Neurosurgery, Tianjin Medical University General Hospital and Laboratory of Neuro-Oncology, Tianjin Neurological Institute. MATERIALS: Mini-RNA isolation kit, human placenta complimentary DNA (cDNA) was produced by Tiangen Biotech (Beijing, China), human glioblastoma U251-MG cells were produced by the Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences. METHODS: A PCR product from the human EGFR, which corresponded to the tyrosine kinase domain of the 3'-end fragment, was used as the T7-promotor for in vitro transcription, siRNA cocktails were generated by in vitro dicing of double stranded RNA. A total of 500, 250 and 125 μg siRNA cocktails were transiently transfected into U251 glioma cells through the use of the GeneSilencer. MAIN OUTCOME MEASURE: Expression of EGFR was detected by real-time PCR. RESULTS: The total PCR product of the human EGFR, corresponding to the tyrosine kinase domain, is approximately 680 bp in length. The PCR transcriptants included GCC leader sequences and a T7 promoter sequence, with a fragment of EGFR cDNA at the center. The T7 promoter was prepared for in vitro transcription of dsRNA. After dicing for 24 hours, the 21-nt siRNA cocktails were verified by 4% agarose gel. The difference between threshold cycle of a sample assay and threshold cycle of the corresponding endogenous reference (△ Ct) among parental U251 cells and cells transfected with different doses of siRNA cocktails were determined to be 3.06, 7.35, and 10

  19. Aging affects epidermal Langerhans cell development and function and alters their miRNA gene expression profile.

    Science.gov (United States)

    Xu, Ying-Ping; Qi, Rui-Qun; Chen, Wenbin; Shi, Yuling; Cui, Zhi-Zhong; Gao, Xing-Hua; Chen, Hong-Duo; Zhou, Li; Mi, Qing-Sheng

    2012-11-01

    Immunosenescence is a result of progressive decline in immune system function with advancing age. Epidermal Langerhans cells (LCs), belonging to the dendritic cell (DC) family, act as sentinels to play key roles in the skin immune responses. However, it has not been fully elucidated how aging affects development and function of LCs. Here, we systemically analyzed LC development and function during the aging process in C57BL/6J mice, and performed global microRNA (miRNA) gene expression profiles in aged and young LCs. We found that the frequency and maturation of epidermal LCs were significantly reduced in aged mice starting at 12 months of age, while the Langerin expression and ability to phagocytose Dextran in aged LCs were increased compared to LCs from aged and young mice. Functionally, aged LCs were impaired in their capacity to induce OVA-specific CD4+ and CD8+ T cell proliferation. Furthermore, the expression of miRNAs in aged epidermal LCs showed a distinct profile compared to young LCs. Most interestingly, aging-regulated miRNAs potentially target TGF-β-dependent and non- TGF-β-dependent signal pathways related to LCs. Overall, our data suggests that aging affects LCs development and function, and that age-regulated miRNAs may contribute to the LC developmental and functional changes in aging.

  20. Interferon alpha2 recombinant and epidermal growth factor modulate proliferation and hypusine synthesis in human epidermoid cancer KB cells.

    Science.gov (United States)

    Caraglia, M; Passeggio, A; Beninati, S; Leardi, A; Nicolini, L; Improta, S; Pinto, A; Bianco, A R; Tagliaferri, P; Abbruzzese, A

    1997-06-15

    We previously found that interferon alpha2 recombinant (IFNalpha) increases the expression of epidermal growth factor receptor (EGF-R) in the human epidermoid cancer KB cell line. Here we report the effects of IFNalpha and epidermal growth factor (EGF) on KB cell cycle kinetics. IFNalpha (1000 i.u./ml) for 48 h decreased the S-phase fraction and diminished the expression of Ki67 and proliferating cell nuclear antigen on KB cells. Incubation of IFNalpha-treated KB cells with 10 nM EGF for 12 h reversed these effects. We then studied several biochemical markers of cell proliferation. Ornithine decarboxylase activity was decreased to about one-tenth by IFNalpha and partly restored by EGF. Hypusine is contained only in eukaryotic initiation factor 5A and its levels are correlated with cell proliferation. IFNalpha decreased hypusine synthesis by 75%; exposure of cells to EGF for 12 h restored hypusine synthesis almost completely. We also studied the effects of IFNalpha on the cytotoxicity of the recombinant toxin TP40, which inhibits elongation factor 2 through EGF-R binding and internalization. IFNalpha greatly enhanced the TP40-induced inhibition of protein synthesis in KB cells. In conclusion, IFNalpha, which affects protein synthesis machinery and increases EGF-R expression, enhances the tumoricidal activity of TP40 and hence could be useful in the setting of anti-cancer therapy.

  1. Distribution of natural killer cells and T-lymphocyte subsets in peripheral blood, gallbladder cancer and surrounding tissue

    Institute of Scientific and Technical Information of China (English)

    Gang Liu; Hong Ren; Xue-Jun Sun; Jing-Sen Shi

    2007-01-01

    BACKGROUND:The patient with malignant tumor always show immunologic function drawback and ingravescent with tumor development, especially in the aspect of cell-mediated immunity. This study was undertaken to deifne the relationship between the immune function of local cells and cancer development by investigating the distribution of natural killer (NK) cells and T-lymphocyte subsets in peripheral blood, the cancer tissue and the tissue surrounding gallbladder carcinoma. METHODS:The numbers of CD4+and CD8+T-lymphocytes and NK cells were measured by lfow cytometry in samples taken from gallbladder cancer tissue, the surrounding tissues and peripheral blood of 38 patients, and compared with the numbers in the peripheral blood and gallbladder tissue of 30 patients with cholecystitis as controls. RESULTS:The numbers of CD4+and CD8+T-cells and NK cells in gallbladder cancer tissues were signiifcantly higher than those in the surrounding tissue and gallbladder with gallstone. However, the ratio of CD4+/CD8+was lower in the cancer tissue than that in the surrounding tissue and tissue from gallbladders with gallstones. The distribution of CD4+ and CD8+ T-cells and NK cells in mucous membrane of cholecystitis gallbladder and that in the tissue surrounding gallbladder cancer were signiifcantly different. CONCLUSIONS:Disproportionate and imbalanced distri-bution of NK cells and subsets of T-lymphocytes occurs in the mucous membrane proper of gallbladder cancer and surrounding tissue. Although gallbladder cancer tissue has higher expressions of CD4+, CD8+and NK cells, the immune function is low or in an inhibited state. In gallbladder cancer immunization therapy, local cellular immunological function should be enhanced and the protective barrier improved.

  2. Effects of CS-1 on A431 cell proliferation, cell cycle, and epidermal growth factor receptor signal transduction

    Institute of Scientific and Technical Information of China (English)

    Haiyan Du; Bo Xu; Caixia Wu; Min Li; Fuxiang Ran; Shaoqing Cai; Jingrong Cui

    2012-01-01

    CS-1,a new alkaloid with a molecular formula of C21H20O8N2S,is extracted from traditional Chinese medicine.Previous studies have shown that CS-1 can inhibit the proliferation of several human carcinoma cells in vivo and in vitro.The aims of this study are to investigate the anti-tumor effect and mechanism of CS-1 in epidermal growth factor receptor (EGFR) signaling pathway in human A431 cell line.Through the sulforhodamine B assay,we found that CS-1 inhibited A431 cell proliferation in the concentration- and time-dependent manners.The inhibitory rate ranged from 14.5% to 87.8% after 24 h of incubation.High content screening (HCS) multiparameters cytotoxicity analysis showed that CS-1 at high concentration had slight cytotoxicity that resulted from the cell permeabilization and slight reduction in total mitochondrial mass,whereas no change in nucleus size/morphology and lysosomal mass-pH was found.The cytotoxicity of CS-1 was not a major reason for its antiproliferative effect.Cell cycle analysis indicated that CS-1 induced G1-phase arrest in A431 cells in a timedependent manner at high concentration (2.5 μM),and S-phase arrest at low concentration (0.625 μM).The HCS assay also showed that CS-1 could inhibit the EGFR internalization,extracellular-signal-regulated kinase (Erk)/ mitogen-activated protein kinase translocation to nucleus,the accumulation of phosphorylated protein kinase B (Akt),signal transducer and activator of transcription 3 (STAT3),and cyclin D1 in the nucleus.These results were confirmed by the western blot analysis.CS-1 might inhibit the epidermal growth factor binding to its receptor,resulting in the inhibition of the accumulation of phosphorylated Erk and Akt,and STAT3 in the nucleus,and affecting the transcription of cyclin D1 and cell cycle arrest in G1/S phase.

  3. Bioengineering of cultured epidermis from adult epidermal stem cells using Mebio gel sutable as autologous graft material

    Directory of Open Access Journals (Sweden)

    Lakshmana K Yerneni

    2007-01-01

    Full Text Available Closure of burn wound is the primary requirement in order to reduce morbidity and mortality that are otherwise very high due to non-availability of permanent wound covering materials. Sheets of cultured epidermis grown from autologous epidermal keratinocyte stem cells are accepted world over as one of the best wound covering materials. In a largely populated country like ours where burn casualties occur more frequently due to inadequate safety practices, there is a need for indigenous research inputs to develop such methodologies. The technique to culturing epidermal sheets in vitro involves the basic Reheinwald-Green method with our own beneficial inputs. The technique employs attenuated 3T3 cells as feeders for propagating keratinocyte stem cells that are isolated from the epidermis of an initial skin biopsy of about 5 cm2 from the patient. The cultures are then maintained in Dulbecco's modified Eagle's medium strengthened with Ham's F12 formula, bovine fetal serum and various specific growth-promoting agents and factors in culture flasks under standard culture conditions. The primary cultures thus established would be serially passaged to achieve the required expansion. Our major inputs are into the establishment of (1 an efficient differential trypsinization protocol to isolate large number epidermal keratinocytes from the skin biopsy, (2 a highly specific, unique and foolproof attenuation protocol for 3T3 cells and (3 a specialized and significant decontamination protocol. The fully formed epidermal sheet as verified by immuno-histochemical and light & electron microscopic studies, is lifted on to paraffin gauze by incubating in a neutral protease. The graft is then ready to be transported to the operating theatre for autologous application. We have a capability of growing cultured epidermal sheets sufficient enough to cover 40 per cent burn wound in 28 days. The preliminary small area clinical applications undertaken so far revealed

  4. Althaea rosea Cavanil and Plantago major L. suppress neoplastic cell transformation through the inhibition of epidermal growth factor receptor kinase.

    Science.gov (United States)

    Choi, Eun-Sun; Cho, Sung-Dae; Shin, Ji-Ae; Kwon, Ki Han; Cho, Nam-Pyo; Shim, Jung-Hyun

    2012-10-01

    For thousands of years in Asia, Althaea rosea Cavanil (ARC) and Plantago major L. (PML) have been used as powerful non-toxic therapeutic agents that inhibit inflammation. However, the anticancer mechanisms and molecular targets of ARC and PML are poorly understood, particularly in epidermal growth factor (EGF)-induced neoplastic cell transformation. The aim of this study was to evaluate the chemopreventive effects and mechanisms of the methanol extracts from ARC (MARC) and PML (MPML) in EGF-induced neoplastic cell transformation of JB6 P+ mouse epidermal cells using an MTS assay, anchorage-independent cell transformation assay and western blotting. Our results showed that MARC and MPML significantly suppressed neoplastic cell transformation by inhibiting the kinase activity of the EGF receptor (EGFR). The activation of EGFR by EGF was suppressed by MARC and MPML treatment in EGFR(+/+) cells, but not in EGFR(-/-) cells. In addition, MARC and MPML inhibited EGF-induced cell proliferation in EGFR-expressing murine embryonic fibroblasts (EGFR(+/+)). These results strongly indicate that EGFR targeting by MARC and MPML may be a good strategy for chemopreventive or chemotherapeutic applications.

  5. Degradation of Epidermal Growth Factor Receptor Mediates Dasatinib-Induced Apoptosis in Head and Neck Squamous Cell Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Yu-Chin Lin

    2012-06-01

    Full Text Available Epidermal growth factor receptor (EGFR is an important oncoprotein that promotes cell growth and proliferation. Dasatinib, a bcr-abl inhibitor, has been approved clinically for the treatment of chronic myeloid leukemia and demonstrated to be effective against solid tumors in vitro through Src inhibition. Here, we disclose that EGFR degradation mediated dasatinib-induced apoptosis in head and neck squamous cell carcinoma (HNSCC cells. HNSCC cells, including Ca9-22, FaDu, HSC3, SAS, SCC-25, and UMSCC1, were treated with dasatinib, and cell viability, apoptosis, and underlying signal transduction were evaluated. Dasatinib exhibited differential sensitivities against HNSCC cells. Growth inhibition and apoptosis were correlated with its inhibition on Akt, Erk, and Bcl-2, irrespective of Src inhibition. Accordingly, we found that down-regulation of EGFR was a determinant of dasatinib sensitivity. Lysosome inhibitor reversed dasatinib-induced EGFR down-regulation, and c-cbl activity was increased by dasatinib, indicating that dasatinib-induced EGFR down-regulation might be through c-cbl-mediated lysosome degradation. Increased EGFR activation by ligand administration rescued cells from dasatinib-induced apoptosis, whereas inhibition of EGFR enhanced its apoptotic effect. Estrogen receptor α (ERα was demonstrated to play a role in Bcl-2 expression, and dasatinib inhibited ERα at the pretranslational level. ERα was associated with EGFR in dasatinib-treated HNSCC cells. Furthermore, the xenograft model showed that dasatinib inhibited HSC3 tumor growth through in vivo down-regulation of EGFR and ERα. In conclusion, degradation of EGFR is a novel mechanism responsible for dasatinib-induced apoptosis in HNSCC cells.

  6. Langerhans cells are not required for epidermal V gamma 3 T cell homeostasis and function

    NARCIS (Netherlands)

    Taveirne, Sylvie; De Colvenaer, Veerle; Van Den Broeck, Tina; Van Ammel, Els; Bennett, Clare L.; Taghon, Tom; Vandekerckhove, Bart; Plum, Jean; Clausen, Bjorn E.; Kaplan, Daniel H.; Leclercq, Georges

    2011-01-01

    This study tested the hypothesis that V gamma 3 TCR-bearing T cells are influenced by LCs. V gamma 3 T cells and LCs are located in the epidermis of mice. V gamma 3 T cells represent the main T cell population in the skin epithelium and play a crucial role in maintaining the skin integrity, whereas

  7. Reconstruction of damaged cornea by autologous transplantation of epidermal adult stem cells.

    Science.gov (United States)

    Yang, Xueyi; Moldovan, Nicanor I; Zhao, Qingmei; Mi, Shengli; Zhou, Zhenhui; Chen, Dan; Gao, Zhimin; Tong, Dewen; Dou, Zhongying

    2008-06-05

    It is crucial for the treatment of severe ocular surface diseases such as Stevens-Johnson syndrome (SJS) and ocular cicatricial pemphigoid (OCP) to find strategies that avoid the risks of allograft rejection and immunosuppression. Here, we report a new strategy for reconstructing the damaged corneal surface in a goat model of total limbal stem cell deficiency (LSCD) by autologous transplantation of epidermal adult stem cells (EpiASC). EpiASC derived from adult goat ear skin by explant culture were purified by selecting single cell-derived clones. These EpiASC were cultivated on denuded human amniotic membrane (HAM) and transplanted onto goat eyes with total LSCD. The characteristics of both EpiASC and reconstructed corneal epithelium were identified by histology and immunohistochemistry. The clinical characteristic of reconstructed corneal surface was observed by digital camera. Ten LSCD goats (10 eyes) were treated with EpiASC transplantation, leading to the restoration of corneal transparency and improvement of postoperative visual acuity to varying degrees in 80.00% (8/10) of the experimental eyes. The corneal epithelium of control groups either with HAM transplantation only or without any transplantation showed irregular surfaces, diffuse vascularization, and pannus on the entire cornea. The reconstructed corneal epithelium (RCE) expressed CK3, CK12, and PAX-6 and had the function of secreting glycocalyx-like material (AB-PAS positive). During the follow-up period, all corneal surfaces remained transparent and there were no serious complications. We also observed that the REC expressed CK1/10 weakly at six months after operation but not at 12 months after operation, suggesting that the REC was derived from grafted EpiASC. Our results showed that EpiASC repaired the damaged cornea of goats with total LSCD and demonstrated that EpiASC can be induced to differentiate into corneal epithelial cell types in vivo, which at least in part correlated with down

  8. Epidermal growth factor receptor (EGFR-RAS signaling pathway in penile squamous cell carcinoma.

    Directory of Open Access Journals (Sweden)

    Hong-Feng Gou

    Full Text Available Penile Squamous Cell Carcinoma (SCC is a rare cancer with poor prognosis and limited response to conventional chemotherapy. The genetic and epigenetic alterations of Epidermal Growth Factor Receptor (EGFR-RAS-RAF signaling in penile SCC are unclear. This study aims to investigate four key members of this pathway in penile SCC. We examined the expression of EGFR and RAS-association domain family 1 A (RASSF1A as well as the mutation status of K-RAS and BRAF in 150 cases of penile SCC. EGFR and RASSF1A expression was evaluated by immunohistochemistry. KRAS mutations at codons 12 and 13, and the BRAF mutation at codon 600 were analyzed on DNA isolated from formalin fixed paraffin embedded tissues by direct genomic sequencing. EGFR expression was positive in all specimens, and its over-expression rate was 92%. RASSF1A expression rate was only 3.42%. Significant correlation was not found between the expression of EGFR or RASSF1A and tumor grade, pT stage or lymph node metastases. The detection of KRAS and BRAF mutations analysis was performed in 94 and 83 tumor tissues, respectively. We found KRAS mutation in only one sample and found no BRAF V600E point mutation. In summary, we found over-expression of EGFR in the majority cases of penile SCC, but only rare expression of RASSF1A, rare KRAS mutation, and no BRAF mutation in penile SCC. These data suggest that anti-EGFR agents may be potentially considered as therapeutic options in penile SCC.

  9. Cell Density-Dependent Upregulation of PDCD4 in Keratinocytes and Its Implications for Epidermal Homeostasis and Repair

    Directory of Open Access Journals (Sweden)

    Tao Wang

    2015-12-01

    Full Text Available Programmed cell death 4 (PDCD4 is one multi-functional tumor suppressor inhibiting neoplastic transformation and tumor invasion. The role of PDCD4 in tumorigenesis has attracted more attention and has been systematically elucidated in cutaneous tumors. However, the normal biological function of PDCD4 in skin is still unclear. In this study, for the first time, we find that tumor suppressor PDCD4 is uniquely induced in a cell density-dependent manner in keratinocytes. To determine the potential role of PDCD4 in keratinocyte cell biology, we show that knockdown of PDCD4 by siRNAs can promote cell proliferation in lower cell density and partially impair contact inhibition in confluent HaCaT cells, indicating that PDCD4 serves as an important regulator of keratinocytes proliferation and contact inhibition in vitro. Further, knockdown of PDCD4 can induce upregulation of cyclin D1, one key regulator of the cell cycle. Furthermore, the expression patterns of PDCD4 in normal skin, different hair cycles and the process of wound healing are described in detail in vivo, which suggest a steady-state regulatory role of PDCD4 in epidermal homeostasis and wound healing. These findings provide a novel molecular mechanism for keratinocytes’ biology and indicate that PDCD4 plays a role in epidermal homeostasis.

  10. GlyRα2, not GlyRα3, modulates the receptive field surround of OFF retinal ganglion cells.

    Science.gov (United States)

    Zhang, Chi; Nobles, Regina D; McCall, Maureen A

    2015-01-01

    Receptive fields (RFs) of most retinal ganglion cells (RGCs) consist of an excitatory center and suppressive surround. The RF center arises from the summation of excitatory bipolar cell glutamatergic inputs, whereas the surround arises from lateral inhibitory inputs. In the retina, both gamma amino butyric acid (GABA) and glycine are inhibitory neurotransmitters. A clear role for GABAergic inhibition modulating the RGC RF surround has been demonstrated across species. Glycinergic inhibition is more commonly associated with RF center modulation, although there is some evidence that it may contribute to the RF surround. The synaptic glycinergic chloride channels are formed by three homomeric β and two homomeric α subunits that can be glycine receptor (GlyR) α1, α2, α3, or α4. GlyRα composition is responsible for currents with distinct decay kinetics. Their expression within the inner plexiform laminae and neuronal subtypes also differ. We studied the role of GlyR subunit selective modulation of RGC RF surrounds, using mice lacking GlyRα2 (Glra2 -/-), GlyRα3 (Glra3 -/-), or both (Glra2/3 -/-). We chose this molecular genetic approach instead of pharmacological manipulation because there are no subunit selective antagonists and strychnine blocks all GlyRs. Comparisons of annulus-evoked responses among wild type (WT) and GlyRα knockouts (Glra2 -/-, Glra3 -/- and Glra2/3 -/-) show that GlyRα2 inhibition enhances RF surround suppression and post-stimulus excitation in only WT OFF RGCs. Similarities in the responses in Glra2 -/- and Glra2/3 -/- RGCs verify these conclusions. Based on previous and current data, we propose that GlyRα2-mediated input uses a crossover inhibitory circuit. Further, we suggest that GlyRα2 modulates the OFF RGC RF center and surround independently. In summary, our results define a selective GlyR subunit-specific control of RF surround suppression in OFF RGCs.

  11. Mammary phenotypic expression induced in epidermal cells by embryonic mammary mesenchyme.

    Science.gov (United States)

    Cunha, G R; Young, P; Christov, K; Guzman, R; Nandi, S; Talamantes, F; Thordarson, G

    1995-01-01

    The goal of this research was to establish methods for inducing mammary epithelial differentiation from nonmammary epithelium. For this purpose, mid-ventral or dorsal epidermis (skin epithelium; SKE) from 13-day rat or mouse embryos was associated with 13-day embryonic mouse mammary mesenchyme (mammary gland mesenchyme; MGM) (mouse MGM+rat or mouse SKE). The resultant MGM+SKE recombinants as well as controls (homotypic mouse mammary recombinants, homotypic mouse skin recombinants and mouse mammary mesenchyme by itself) were grafted under the renal capsule of syngeneic or athymic female nude mouse hosts. Most female hosts were induced to undergo lactogenesis by grafting an adult pituitary which elicited a state of hyperprolactinemia. Tissue recombinants of mouse MGM+rat or mouse SKE grown for 1 month in vivo formed a hair-bearing keratinized skin from which mammary ductal structures extended into the mesenchyme. The ducts were composed of columnar luminal epithelial cells as well as basal, actin-positive myoepithelial cells. When grown in pituitary-grafted hosts, the ductal epithelial cells expressed casein and alpha-lactalbumin as judged by immunocytochemistry. The expression of caseins in MGM+SKE recombinants was confirmed by Western blot. The epithelial cells in mouse MGM+rat SKE recombinants expressing milk proteins were shown to be rat cells while the surrounding connective tissue was composed of mouse cells based upon staining with Hoechst dye 33258. Using mammary-specific markers, these studies confirmed the earlier morphological studies of Propper and unequivocally demonstrated for the first time that embryonic mammary mesenchyme can induce morphological and functional mammary differentiation from nonmammary epithelium.

  12. RNA interference for epidermal growth factor receptor enhances the radiosensitivity of esophageal squamous cell carcinoma cell line Eca109.

    Science.gov (United States)

    Zhang, Heping; Li, Jiancheng; Cheng, Wenfang; Liu, D I; Chen, Cheng; Wang, Xiaoying; Lu, Xujing; Zhou, Xifa

    2015-09-01

    The present study investigated the effects of small interfering RNAs (siRNAs) specific to the epidermal growth factor receptor (EGFR) gene, on the radiosensitivity of esophageal squamous cell carcinoma cells. EGFR gene siRNAs (EGFR-siRNA) were introduced into esophageal cancer Eca109 cells using Lipofectamine® 2000. The EGFR messenger (m)RNA expression levels, EGFR protein expression and cell growth were assessed using reverse transcription-polymerase chain reaction analysis, western blot analysis and a Cell Counting Kit-8 (CCK-8), respectively. In addition, colony assays were used to determine the inhibitory effects of X-ray radiation on EGFR-silenced cells. EGFR mRNA and protein levels were reduced in the Eca109 cells transfected with EGFR-siRNA. The relative EGFR mRNA expression levels were reduced to 26.74, 9.52 and 4.61% in Eca109 cells transfected with EGFR-siRNA1, 2 and 3, respectively. These mRNA levels were significantly reduced compared with the those of the control group (42.44%; P34.14% in Eca109 cells transfected with EGFR-siRNA1, 2 and 3, respectively. These protein levels were significantly reduced compared with those of the control group (78.57%; P<0.0001). Transfection with siRNA1 resulted in the greatest reduction in EGFR protein expression, with an inhibition rate of 72.84%. This reduction in EGFR expression inhibited the proliferation of Eca109 cells, which was identified using the CCK-8 assay. The proliferation inhibition ratio was 28.2%. The cells treated with irradiation in addition to EGFR-siRNA, demonstrated reduced radiobiological parameters (D0, Dq and SF2) compared with those of cells treated with irradiation only, with a sensitization enhancing ratio of 1.5. In conclusion, suppression of EGFR expression may enhance the radiosensitivity of esophageal cancer Eca109 cells and therefore may represent a promising approach for future clinical practice.

  13. Shape-induced terminal differentiation of human epidermal stem cells requires p38 and is regulated by histone acetylation.

    Directory of Open Access Journals (Sweden)

    John T Connelly

    Full Text Available Engineered model substrates are powerful tools for examining interactions between stem cells and their microenvironment. Using this approach, we have previously shown that restricted cell adhesion promotes terminal differentiation of human epidermal stem cells via activation of serum response factor (SRF and transcription of AP-1 genes. Here we investigate the roles of p38 MAPK and histone acetylation. Inhibition of p38 activity impaired SRF transcriptional activity and shape-induced terminal differentiation of human keratinocytes. In addition, inhibiting p38 reduced histone H3 acetylation at the promoters of SRF target genes, FOS and JUNB. Although histone acetylation correlated with SRF transcriptional activity and target gene expression, treatment with the histone de-acetylase inhibitor, trichostatin A (TSA blocked terminal differentiation on micro-patterned substrates and in suspension. TSA treatment simultaneously maintained expression of LRIG1, TP63, and ITGB1. Therefore, global histone de-acetylation represses stem cell maintenance genes independent of SRF. Our studies establish a novel role for extrinsic physical cues in the regulation of chromatin remodeling, transcription, and differentiation of human epidermal stem cells.

  14. sAPP as a regulator of dendrite motility and melanin release in epidermal melanocytes and melanoma cells.

    Science.gov (United States)

    Quast, Thomas; Wehner, Sven; Kirfel, Gregor; Jaeger, Klaus; De Luca, Michele; Herzog, Volker

    2003-09-01

    Numerous factors including ultraviolet (UV) radiation and growth factors regulate the specific function of epidermal melanocytes. A recently discovered epidermal growth factor is sAPP, the soluble N-terminal ectodomain of the beta-amyloid precursor protein (APP). Using whole mount preparations of isolated human epidermis, we detected a small population of basal cells, which expressed exceptionally high levels of APP. These cells were identified as melanocytes, which, similar to keratinocytes and neuronal cells, expressed the three APP isoforms 695, 751, and 770. They differed in their expression pattern from that of neuronal cells by expressing only low levels of APP 695. Melanocytes and melanoma cells in vitro released, in addition to keratinocytes, large quantities of sAPP. Because of its growth factor function, we studied possible effects of sAPP on melanocytes. Recombinant sAPP strongly increased lamellipodia activity at dendritic tips, an effect that coincided with increased release of melanin particles. Our observations point to the possible use of APP as an immunocytochemical marker for melanocytes. They suggest that sAPP derived from keratinocytes and/or melanocytes belongs to a family of factors operating in the paracrine and/or autocrine regulation of melanocyte function.

  15. Characterization of a Putative Receptor Binding Surface on Skint-1, a Critical Determinant of Dendritic Epidermal T Cell Selection*

    Science.gov (United States)

    Salim, Mahboob; Knowles, Timothy J.; Hart, Rosie; Mohammed, Fiyaz; Woodward, Martin J.; Willcox, Carrie R.; Overduin, Michael; Hayday, Adrian C.; Willcox, Benjamin E.

    2016-01-01

    Dendritic epidermal T cells (DETC) form a skin-resident γδ T cell population that makes key contributions to cutaneous immune stress surveillance, including non-redundant contributions to protection from cutaneous carcinogens. How DETC become uniquely associated with the epidermis was in large part solved by the identification of Skint-1, the prototypic member of a novel B7-related multigene family. Expressed only by thymic epithelial cells and epidermal keratinocytes, Skint-1 drives specifically the development of DETC progenitors, making it the first clear candidate for a selecting ligand for non-MHC/CD1-restricted T cells. However, the molecular mechanisms underpinning Skint-1 activity are unresolved. Here, we provide evidence that DETC selection requires Skint-1 expression on the surface of thymic epithelial cells, and depends upon specific residues on the CDR3-like loop within the membrane-distal variable domain of Skint-1 (Skint-1 DV). Nuclear magnetic resonance of Skint-1 DV revealed a core tertiary structure conserved across the Skint family, but a highly distinct surface charge distribution, possibly explaining its unique function. Crucially, the CDR3-like loop formed an electrostatically distinct surface, featuring key charged and hydrophobic solvent-exposed residues, at the membrane-distal tip of DV. These results provide the first structural insights into the Skint family, identifying a putative receptor binding surface that directly implicates Skint-1 in receptor-ligand interactions crucial for DETC selection. PMID:26917727

  16. Induction of PD-L1 expression by epidermal growth factor receptor–mediated signaling in esophageal squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Zhang W

    2017-02-01

    Full Text Available Wencheng Zhang,1 Qingsong Pang,1 Cihui Yan,2 Qifeng Wang,3 Jingsong Yang,3 Shufei Yu,3 Xiao Liu,3 Zhiyong Yuan,1 Ping Wang,1 Zefen Xiao3 1Department of Radiation Oncology, 2Department of Immunology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin, People’s Republic of China; 3Department of Radiation Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, People’s Republic of China Purpose: The purpose of this study was to investigate the potential effect of activation of epidermal growth factor receptor (EGFR signaling pathway on the expression of programmed death-ligand 1 (PD-L1 in esophageal squamous cell carcinoma (ESCC cells with EGFR overexpression. Methods: Flow cytometry and Western blot methods were used to assess PD-L1 expression on ESCC cells when EGFR signaling pathway was activated by epidermal growth factor (EGF with or without EGFR-specific inhibitor AG-1478, and then EGFR signaling array was applied to analyze the potential signaling pathways involved. Results: This study found that PD-L1 expression increased significantly in an EGFR-dependent manner by the activation of EGFR signaling and decreased sharply when EGFR signaling was blocked. The upregulated expression of PD-L1 was not associated with EGFR-STAT3 signaling pathway, but may be affected by EGFR–PI3K–AKT, EGFR–Ras–Raf–Erk, and EGR–PLC-γ signaling pathways. Conclusion: The expression of PD-L1 can be regulated by EGFR signaling activation in ESCC, which indicates an important role for EGFR-mediated immune escape and potential molecular pathways for EGFR-targeted therapy and immunotherapy. Keywords: epidermal growth factor receptor, programmed death-ligand 1, esophageal squamous cell carcinoma, immune checkpoint

  17. Correlation of epidermal growth factor receptor overexpression with increased epidermal growth factor receptor gene copy number in esophageal squamous cell carcinomas

    Institute of Scientific and Technical Information of China (English)

    YANG Yan-li; XU Kan-lun; ZHOU Yan; GAO Xin; CHEN Li-rong

    2012-01-01

    Background Esophageal squamous cell carcinoma (ESCC) is one of the most frequent malignancies in China and epidermal growth factor receptor (EGFR) is widely distributed in human epithelial cell membrane.The aim of this study was to investigate the protein overexpression and gene copy number of EGFR in ESCC,and help to identify patients who may benefit from EGFR targeted therapies.Methods Immunohistochemistry (IHC) was performed to analyze the expression of EGFR in 105 cases of ESCC,16 cases of squamous epithelial atypical hyperplasia,and 11 cases of normal esophageal tissue.Fluorescence in situ hybridization (FISH) was performed to analyze the gene copy number in 80 cases of ESCC,eight cases of squamous epithelial atypical hyperplasia,and eight samples of normal esophageal tissue.Results The IHC-positive rates of EGFR in 105 cases of ESCC,16 cases of squamous epithelial atypical hyperplasia,and 11 normal esophageal tissues were 97% (102/105),44% (7/16),and 18% (2/11) respectively.The difference in the expression of EGFR among different esophageal tissue groups had statistically significance (P <0.05).Among the 105 cases of ESCC,overexpression of EGFR was found in 90 cases (86%),of which 55 cases scored 3+ for EGFR staining and 35 cases scored 2+.In ESCC,the expression of EGFR was significantly correlated with depth of invasion and TNM stage (P<0.05),but not with other parameters.The FISH-positive rates of EGFR in 80 cases of ESCC,the eight cases of squamous epithelial atypical hyperplasia,and eight samples of normal esophageal tissue were 31.3% (25/80),0 (0/8) and 0 (0/8) respectively.In ESCC,EGFR gene amplification was found in 17 (21%) cases,high polysomy in 8 (10%) cases,disomy in 34 cases,low trisomy in 17 cases,and high trisomy in four cases.EGFR FISH-positive was significantly correlated with depth of invasion and lymph node metastasis (P <0.05).EGFR FISH-positive was significantly associated with overexpression of EGFR.Conclusion Protein

  18. Topical grape seed proanthocyandin extract reduces sunburn cells and mutant p53 positive epidermal cell formation, and prevents depletion of Langerhans cells in an acute sunburn model.

    Science.gov (United States)

    Yuan, Xiao-Ying; Liu, Wei; Hao, Jian-Chun; Gu, Wei-Jie; Zhao, Yan-Shuang

    2012-01-01

    The purpose of this study was to investigate whether grape seed proanthocyanidin extract (GSPE) can provide photoprotection against ultraviolet (UV) irradiation. Study has shown that GSPE is a natural oxidant, and is used in many fields such as ischemia-reperfusion injury, chronic pancreatitis, and even cancer. However, the effect of GSPE on UV irradiation is as yet unknown. Cutaneous areas on the backs of normal volunteers were untreated or treated with GSPE solutions or vehicles 30 min before exposure to two minimal erythema doses (MED) of solar simulated radiation. Cutaneous areas at different sites were examined histologically for the number of sunburn cells, or immunohistochemically for Langerhans cells and mutant p53 epidermal cells. On histological and immunohistochemical examination, skin treated with GSPE before UV radiation showed fewer sunburn cells and mutant p53-positive epidermal cells and more Langerhans cells compared with skin treated with 2-MED UV radiation only (p<0.001, p<0.001, and p<0.01, respectively). GSPE may be a possible preventive agent for photoprotection.

  19. Mitochondrial tolerance to single and repeat exposure to simulated sunlight in human epidermal and dermal skin cells.

    Science.gov (United States)

    Kelly, J; Murphy, J E J

    2016-12-01

    Sunlight represents the primary threat to mitochondrial integrity in skin given the unique nature of the mitochondrial genome and its proximity to the electron transport chain. The accumulation of mitochondrial DNA (mtDNA) mutations is a key factor in many human pathologies and this is linked to key roles of mitochondrial function in terms of energy production and cell regulation. The main objective of this study was to evaluate solar radiation induced changes in mitochondrial integrity, function and dynamics in human skin cells using a Q-Sun solar simulator to deliver a close match to the intensity of summer sunlight. Spontaneously immortalised human skin epidermal keratinocytes (HaCaT) and Human Dermal Fibroblasts (HDFn) were divided into two groups. Group A were irradiated once and Group B twice 7days apart and evaluated using cell survival, viability and mitochondrial membrane potential (MMP) and mass at 1, 4 and 7days post one exposure for Group A and 1, 4, 7 and 14days post second exposure for Group B. Viability and survival of HaCaT and HDFn cells decreased after repeat exposure to Simulated Sunlight Irradiation (SSI) with no recovery. HDFn cells showed no loss in MMP after one or two exposures to SSI compared to HaCaT cells which showed a periodic loss of MMP after one exposure with a repeat exposure causing a dramatic decrease from which cells did not recover. Mitochondrial Mass in exposed HDFn cells was consistent with control after one or two exposures to SSI; however mitochondrial mass was significantly decreased in HaCaT cells. Data presented here suggests that mitochondria in epidermal cells are more sensitive to sunlight damage compared to mitochondria in dermal cells, despite their origin, confirming a skin layer specific sensitivity to sunlight, but not as expected. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Isolating subpopulations of human epidermal basal cells based on polyclonal serum against trypsin-resistant CSPG4 epitopes

    DEFF Research Database (Denmark)

    Gunnarsson, Anders Patrik Alexander; Christensen, Rikke; Prætorius, Jeppe

    2016-01-01

    unable to study these keratinocytes isolated directly from skin samples by flow cytometry. By choosing epitopes of CSPG4 relatively close to the cell membrane we were able to generate a polyclonal antibody that successfully detects CSPG4 on keratinocytes after trypsinization. Although CSPG4-positive......Chondroitin sulfate proteoglycan 4 (CSPG4) is highly expressed by human epidermal keratinocytes located at the tip of the dermal papilla where keratinocytes show characteristics of stem cells. However, since available antibodies to CSPG4 are directed against trypsin-sensitive epitopes we have been...... that CSPG4-positive basal cell keratinocytes are distinct from CSPG4-negative basal cell keratinocytes. Our study demonstrates that it is possible to generate antibodies against trypsin-resistant epitopes of CSPG4. Our study also documents a marked change in behaviour upon cell culturing and challenges...

  1. Papular Epidermal Nevus with Skyline Basal Cell Layer (PENS): Three New Cases and Review of the Literature.

    Science.gov (United States)

    Luna, Paula C; Pannizardi, Anabel A; Martin, Carolina I; Vigovich, Felix; Casas, José G; Larralde, Margarita

    2016-05-01

    Papular epidermal nevus with skyline basal cell layer (PENS) is a recently described type of epidermal nevus with characteristic histopathologic findings, mainly regular, rectangular acanthosis and a well-demarcated basal cell layer with clear palisading and separation between basal cell nuclei and the first row of Malpighian cell nuclei. Although the first reports described randomly distributed lesions appearing sporadically in otherwise healthy patients, cases of Blaschkoid distribution, lesions associated with extracutaneous manifestations, and familial cases have been reported. We performed a review of the clinical charts of all patients with histologic diagnosis of PENS in our hospital. We evaluated epidemiologic, clinical, and histologic features. We then reviewed the literature with a particular emphasis on the presence or absence of extra-cutaneous associations. Three patients with PENS are described. One had a single lesion, one had three lesions, and one, a patient with mild developmental delay, a curved penis, and hypospadias, had multiple lesions. The probability of having extracutaneous manifestations is 6.3 times as great in individuals with more than four lesions. Therefore these patients may need closer follow-up. © 2016 Wiley Periodicals, Inc.

  2. Dnmt3a and Dnmt3b Associate with Enhancers to Regulate Human Epidermal Stem Cell Homeostasis.

    Science.gov (United States)

    Rinaldi, Lorenzo; Datta, Debayan; Serrat, Judit; Morey, Lluis; Solanas, Guiomar; Avgustinova, Alexandra; Blanco, Enrique; Pons, José Ignacio; Matallanas, David; Von Kriegsheim, Alex; Di Croce, Luciano; Benitah, Salvador Aznar

    2016-10-06

    The genome-wide localization and function of endogenous Dnmt3a and Dnmt3b in adult stem cells are unknown. Here, we show that in human epidermal stem cells, the two proteins bind in a histone H3K36me3-dependent manner to the most active enhancers and are required to produce their associated enhancer RNAs. Both proteins prefer super-enhancers associated to genes that either define the ectodermal lineage or establish the stem cell and differentiated states. However, Dnmt3a and Dnmt3b differ in their mechanisms of enhancer regulation: Dnmt3a associates with p63 to maintain high levels of DNA hydroxymethylation at the center of enhancers in a Tet2-dependent manner, whereas Dnmt3b promotes DNA methylation along the body of the enhancer. Depletion of either protein inactivates their target enhancers and profoundly affects epidermal stem cell function. Altogether, we reveal novel functions for Dnmt3a and Dnmt3b at enhancers that could contribute to their roles in disease and tumorigenesis.

  3. Proton extrusion is an essential signalling component in the HR of epidermal single cells in the barley-powdery mildew interaction

    DEFF Research Database (Denmark)

    Zhou, F.S.; Andersen, C.H.; Burhenne, K.;

    2000-01-01

    between the epidermal cell and underlying mesophyll cells; (2) scavenger treatment reduces HR; (3) treatment of leaves with low-pH (3.5) citrate and succinate buffers causes more cells to undergo HR in the compatible interaction, while treatment with the same buffers at pH 5.5 reduces the number of HR...

  4. Papular Epidermal Nevus with “Skyline” Basal Cell Layer Syndrome – Natural Course: Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Carole Anouk Zahn

    2017-01-01

    Full Text Available Papular epidermal nevus with “skyline” basal cell layer (PENS is a very rare type of keratinocytic nevus and is associated with extracutaneous findings such as neurological symptoms in about 50% of the cases. Therefore, it is also referred to as PENS syndrome. Clinically visible hyperkeratotic papules and plaques already appear at birth or shortly thereafter, while neurological symptoms such as epilepsy and mental retardation manifest themselves during childhood. Genetics suggests gonadal mosaicism as a possible cause for the disease. Another hypothesis is that genetic mutation can occur in a mendelian trait or through a paradominant inheritance.

  5. Involvement of aquaporin-3 in epidermal growth factor receptor signaling via hydrogen peroxide transport in cancer cells.

    Science.gov (United States)

    Hara-Chikuma, Mariko; Watanabe, Sachiko; Satooka, Hiroki

    2016-03-18

    Aquaporin 3 (AQP3), a water/glycerol channel protein, is capable of transporting hydrogen peroxide (H2O2). Here, we show that AQP3-mediated intracellular H2O2 is involved in epidermal growth factor (EGF)-induced cell signaling and its dependent cell function in the EGF receptor (EGFR)-positive cancer cell lines A431 and H1666. AQP3 knockdown suppressed the transport into the cells of extracellular H2O2 produced in response to EGF in A431 and H1666 cells. EGF-induced Erk and Akt activation, which occurred through SHP2 and/or PTEN modulation, was impaired by AQP3 knockdown. Cell growth and migration induced by EGF stimulation were attenuated in AQP3 knockdown cells compared with those in control cells. Coincidentally, tumor growth of A431 cell xenografts in immunodeficient mice was decreased by AQP3 knockdown. Accordingly, a xenograft with AQP3 knockdown A431 cells significantly enhanced the survival of recipient mice compared with the transplantation with control cells. In addition, AQP3 associated with EGFR and NADPH oxidase 2, which we propose is linked to AQP3 producing a localized increase in intracellular H2O2 to function as a second messenger during EGFR cell signaling. Therefore, our findings suggest that AQP3 is required for EGF-EGFR cell signaling in cancer cells and is a therapeutic target for cancer progression.

  6. Induction of PD-L1 expression by epidermal growth factor receptor–mediated signaling in esophageal squamous cell carcinoma

    Science.gov (United States)

    Zhang, Wencheng; Pang, Qingsong; Yan, Cihui; Wang, Qifeng; Yang, Jingsong; Yu, Shufei; Liu, Xiao; Yuan, Zhiyong; Wang, Ping; Xiao, Zefen

    2017-01-01

    Purpose The purpose of this study was to investigate the potential effect of activation of epidermal growth factor receptor (EGFR) signaling pathway on the expression of programmed death-ligand 1 (PD-L1) in esophageal squamous cell carcinoma (ESCC) cells with EGFR overexpression. Methods Flow cytometry and Western blot methods were used to assess PD-L1 expression on ESCC cells when EGFR signaling pathway was activated by epidermal growth factor (EGF) with or without EGFR-specific inhibitor AG-1478, and then EGFR signaling array was applied to analyze the potential signaling pathways involved. Results This study found that PD-L1 expression increased significantly in an EGFR-dependent manner by the activation of EGFR signaling and decreased sharply when EGFR signaling was blocked. The upregulated expression of PD-L1 was not associated with EGFR-STAT3 signaling pathway, but may be affected by EGFR–PI3K–AKT, EGFR–Ras–Raf–Erk, and EGR–PLC-γ signaling pathways. Conclusion The expression of PD-L1 can be regulated by EGFR signaling activation in ESCC, which indicates an important role for EGFR-mediated immune escape and potential molecular pathways for EGFR-targeted therapy and immunotherapy.

  7. The cell signaling adaptor protein EPS-8 is essential for C. elegans epidermal elongation and interacts with the ankyrin repeat protein VAB-19.

    Directory of Open Access Journals (Sweden)

    Mei Ding

    Full Text Available The epidermal cells of the C. elegans embryo undergo coordinated cell shape changes that result in the morphogenetic process of elongation. The cytoskeletal ankyrin repeat protein VAB-19 is required for cell shape changes and localizes to cell-matrix attachment structures. The molecular functions of VAB-19 in this process are obscure, as no previous interactors for VAB-19 have been described.In screens for VAB-19 binding proteins we identified the signaling adaptor EPS-8. Within C. elegans epidermal cells, EPS-8 and VAB-19 colocalize at cell-matrix attachment structures. The central domain of EPS-8 is necessary and sufficient for its interaction with VAB-19. eps-8 null mutants, like vab-19 mutants, are defective in epidermal elongation and in epidermal-muscle attachment. The eps-8 locus encodes two isoforms, EPS-8A and EPS-8B, that appear to act redundantly in epidermal elongation. The function of EPS-8 in epidermal development involves its N-terminal PTB and central domains, and is independent of its C-terminal SH3 and actin-binding domains. VAB-19 appears to act earlier in the biogenesis of attachment structures and may recruit EPS-8 to these structures.EPS-8 and VAB-19 define a novel pathway acting at cell-matrix attachments to regulate epithelial cell shape. This is the first report of a role for EPS-8 proteins in cell-matrix attachments. The existence of EPS-8B-like isoforms in Drosophila suggests this function of EPS-8 proteins could be conserved among other organisms.

  8. Isolating subpopulations of human epidermal basal cells based on polyclonal serum against trypsin-resistant CSPG4 epitopes.

    Science.gov (United States)

    Gunnarsson, Anders Patrik; Christensen, Rikke; Praetorius, Jeppe; Jensen, Uffe Birk

    2017-01-15

    Chondroitin sulfate proteoglycan 4 (CSPG4) is highly expressed by human epidermal keratinocytes located at the tip of the dermal papilla where keratinocytes show characteristics of stem cells. However, since available antibodies to CSPG4 are directed against trypsin-sensitive epitopes we have been unable to study these keratinocytes isolated directly from skin samples by flow cytometry. By choosing epitopes of CSPG4 relatively close to the cell membrane we were able to generate a polyclonal antibody that successfully detects CSPG4 on keratinocytes after trypsinization. Although CSPG4-positive basal cells express higher levels of Itgβ1 the colony-forming efficiency is slightly lower than CSPG4-negative basal cells. Sorting the directly isolated keratinocytes based on Itgβ1 did not reveal differences in colony-forming efficiency between keratinocytes expressing high or low levels of Itgβ1. However, after the first passage Itgβ1 could be used to predict colony-forming efficiency whether the culture was established from CSPG4-positive or CSPG4-negative basal cell keratinocytes. Although we were unable to detect differences in the colony-forming assay, global gene expression profiling showed that CSPG4-positive basal cell keratinocytes are distinct from CSPG4-negative basal cell keratinocytes. Our study demonstrates that it is possible to generate antibodies against trypsin-resistant epitopes of CSPG4. Our study also documents a marked change in behaviour upon cell culturing and challenges the way we assess for stemness within the human epidermal basal layer.

  9. CPK3-phosphorylated RhoGDI1 is essential in the development of Arabidopsis seedlings and leaf epidermal cells

    Science.gov (United States)

    Wu, Yan

    2013-01-01

    The regulation of Rho of plants (ROP) in morphogenesis of leaf epidermal cells has been well studied, but the roles concerning regulators of ROPs such as RhoGDIs are poorly understood. This study reports that AtRhoGDI1 (GDI1) acts as a versatile regulator to modulate development of seedlings and leaf pavement cells. In mutant gdi1, leaf pavement cells showed shorter lobes in comparison with those in wild type. In GDI1-14 seedlings (GDI1-overexpression line) the growth of lobes in pavement cells was severely suppressed and the development of seedlings was altered. These results indicate that GDI1 plays an essential role in morphogenesis of epidermal pavement cells through modulating the ROP signalling pathways. The interaction between GDI1 and ROP2 or ROP6 was detected in the leaf pavement cells using FRET analysis. Dominant negative, not constitutively active, DN-rop6 could weaken the effect caused by overexpression of GDI1; because the pleiotropic phenotype of GDI1-14 plants was eliminated in the hybrid line GDI1-14 DN-rop6. GDI1 could be phosphorylated by CPK3. Three conserved Ser/Thr residues in GDI1 were determined as targeted amino acids for CPK3. Overexpression of GDI1(3D), not GDI1(3A), could rescue the abnormal growth phenotypes of gdi1-1 seedlings, demonstrating the impact of GDI1 phosphorylation in the development of Arabidopsis. In summary, these results suggest that GDI1 regulation in morphogenesis of seedlings and leaf pavement cells could be undergone through modulating the ROP signalling pathways and the phosphorylation of GDI1 by CPK3 was required for the developmental modulation in Arabidopsis. PMID:23846874

  10. Epidermal growth factor stimulates Rac activation through Src and phosphatidylinositol 3-kinase to promote colonic epithelial cell migration.

    Science.gov (United States)

    Dise, Rebecca S; Frey, Mark R; Whitehead, Robert H; Polk, D Brent

    2008-01-01

    Regulated intestinal epithelial cell migration plays a key role in wound healing and maintenance of a healthy gastrointestinal tract. Epidermal growth factor (EGF) stimulates cell migration and wound closure in intestinal epithelial cells through incompletely understood mechanisms. In this study we investigated the role of the small GTPase Rac in EGF-induced cell migration using an in vitro wound-healing assay. In mouse colonic epithelial (MCE) cell lines, EGF-stimulated wound closure was accompanied by a doubling of the number of cells containing lamellipodial extensions at the wound margin, increased Rac membrane translocation in cells at the wound margin, and rapid Rac activation. Either Rac1 small interfering (si)RNA or a Rac1 inhibitor completely blocked EGF-stimulated wound closure. Whereas EGF failed to activate Rac in colon cells from EGF receptor (EGFR) knockout mice, stable expression of wild-type EGFR restored EGF-stimulated Rac activation and migration. Pharmacological inhibition of either phosphatidylinositol 3-kinase (PI3K) or Src family kinases reduced EGF-stimulated Rac activation. Cotreatment of cells with both inhibitors completely blocked EGF-stimulated Rac activation and localization to the leading edge of cells and lamellipodial extension. Our results present a novel mechanism by which the PI3K and Src signaling cascades cooperate to activate Rac and promote intestinal epithelial cell migration downstream of EGFR.

  11. Protein kinase C is differentially regulated by thrombin, insulin, and epidermal growth factor in human mammary tumor cells

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, M.L.; Tellez-Inon, M.T. (Instituto de Ingenieria Genetica y Biologia Molecular, Buenos Aires (Argentina)); Medrano, E.E.; Cafferatta, E.G.A. (Instituto de Investigaciones Bioquimicas Fundacion Campomar, Buenos Aires (Argentina))

    1988-03-01

    The exposure of serum-deprived mammary tumor cells MCF-7 and T-47D to insulin, thrombin, and epidermal growth factor (EGF) resulted in dramatic modifications in the activity and in the translocation capacity of protein kinase C from cytosol to membrane fractions. Insulin induces a 600% activation of the enzyme after 5 h of exposure to the hormone in MCF-7 cells; thrombin either activates (200% in MCF-7) or down-regulates (in T-47D), and EGF exerts only a moderate effect. Thus, the growth factors studied modulate differentially the protein kinase C activity in human mammary tumor cells. The physiological significance of the results obtained are discussed in terms of the growth response elicited by insulin, thrombin, and EGF.

  12. Epidermal growth factor inhibits glycylsarcosine transport and hPepT1 expression in a human intestinal cell line

    DEFF Research Database (Denmark)

    Nielsen, C U; Amstrup, J; Steffansen, B

    2001-01-01

    (max) decreased from 2.61 +/- 0.4 to 1.06 +/- 0.1 nmol x cm(-2) x min(-1) (n = 3, P PepT1 mRNA (using glucose-6-phosphate dehydrogenase mRNA as control......The human intestinal cell line Caco-2 was used as a model system to study the effects of epidermal growth factor (EGF) on peptide transport. EGF decreased apical-to-basolateral fluxes of [(14)C]glycylsarcosine ([(14)C]Gly-Sar) up to 50.2 +/- 3.6% (n = 6) of control values. Kinetic analysis...... of the fluxes showed that maximal flux (V(max)) of transepithelial transport decreased from 3.00 +/- 0.17 nmol x cm(-2) x min(-1) in control cells to 0.50 +/- 0.07 nmol x cm(-2) x min(-1) in cells treated with 5 ng/ml EGF (n = 6, P

  13. The SKINT1-like gene is inactivated in hominoids but not in all primate species: implications for the origin of dendritic epidermal T cells.

    Directory of Open Access Journals (Sweden)

    Rania Hassan Mohamed

    Full Text Available Dendritic epidermal T cells, which express an invariant Vγ5Vδ1 T-cell receptor and account for 95% of all resident T cells in the mouse epidermis, play a critical role in skin immune surveillance. These γδ T cells are generated by positive selection in the fetal thymus, after which they migrate to the skin. The development of dendritic epidermal T cells is critically dependent on the Skint1 gene expressed specifically in keratinocytes and thymic epithelial cells, suggesting an indispensable role for Skint1 in the selection machinery for specific intraepithelial lymphocytes. Phylogenetically, rodents have functional SKINT1 molecules, but humans and chimpanzees have a SKINT1-like (SKINT1L gene with multiple inactivating mutations. In the present study, we analyzed SKINT1L sequences in representative primate species and found that all hominoid species have a common inactivating mutation, but that Old World monkeys such as olive baboons, green monkeys, cynomolgus macaques and rhesus macaques have apparently functional SKINT1L sequences, indicating that SKINT1L was inactivated in a common ancestor of hominoids. Interestingly, the epidermis of cynomolgus macaques contained a population of dendritic-shaped γδ T cells expressing a semi-invariant Vγ10/Vδ1 T-cell receptor. However, this population of macaque T cells differed from rodent dendritic epidermal T cells in that their Vγ10/Vδ1 T-cell receptors displayed junctional diversity and expression of Vγ10 was not epidermis-specific. Therefore, macaques do not appear to have rodent-type dendritic epidermal T cells despite having apparently functional SKINT1L. Comprehensive bioinformatics analysis indicates that SKINT1L emerged in an ancestor of placental mammals but was inactivated or lost multiple times in mammalian evolution and that Skint1 arose by gene duplication in a rodent lineage, suggesting that authentic dendritic epidermal T cells are presumably unique to rodents.

  14. Differential regulation of human Eag1 channel expression by serum and epidermal growth factor in lung and breast cancer cells

    Directory of Open Access Journals (Sweden)

    Acuña-Macías I

    2015-10-01

    Full Text Available Isabel Acuña-Macías,1 Eunice Vera,1 Alma Yolanda Vázquez-Sánchez,1 María Eugenia Mendoza-Garrido,2 Javier Camacho1 1Department of Pharmacology, 2Department of Physiology, Biophysics and Neurosciences, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Mexico City, Mexico Abstract: Oncogenic ether à-go-go-1 (Eag1 potassium channels are overexpressed in most primary human solid tumors. Low oxygen and nutrient/growth factor concentrations play critical roles in tumorigenesis. However, the mechanisms by which tumor cells survive and proliferate under growth factor-depleted conditions remain elusive. Here, we investigated whether serum-deprived conditions and epidermal growth factor (EGF regulate Eag1 expression in human lung and breast cancer cells. The human cancer cell lines A549 and MCF-7 (from the lungs and breast, respectively were obtained from the American Type Culture Collection and cultured following the manufacturer’s recommendations. Eag1 gene and protein expression were studied by real-time PCR and immunocytochemistry, respectively. Cell proliferation was evaluated using the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide assay, and ERK1/2 phosphorylation was investigated by Western blot. Serum-deprived conditions increased Eag1 mRNA and protein expression in both cell lines. This Eag1 upregulation was prevented by EGF and the ERK1/2 inhibitor U0126 in only lung cancer cells; vascular endothelial growth factor did not prevent Eag1 upregulation. Our results suggest that Eag1 may act as a survival and mitogenic factor under low-serum and nutrient conditions and may be a clinical target during the early stages of tumor development. Keywords: lung cancer, serum deprivation, ether à-go-go, potassium channels, EGF, epidermal growth factor, ERK 1/2

  15. Epidermal growth factor-receptor interaction in rat pheochromocytoma (PC12) and human epidermoid A431 cells: Biochemical and ultrastructural studies

    NARCIS (Netherlands)

    Laat, S.W. de; Boonstra, J.; Mummery, C.L.; Defize, L.; Leunissen, J.; Verkleij, A.J.

    1984-01-01

    Pheochromocytoma cells (clone PC12) have specific plasmamembrane receptors for both epidermal growth factor (EGF) and nerve growth factor (NGF). These growth factors have however, opposite biological effects in PC12 cells; EGF acts mitogenically, while NGF induces differentiation and causes arrest o

  16. Potent endogenous allelopathic compounds in Lepidium sativum seed exudate: effects on epidermal cell growth in Amaranthus caudatus seedlings.

    Science.gov (United States)

    Iqbal, Amjad; Fry, Stephen C

    2012-04-01

    Many plants exude allelochemicals--compounds that affect the growth of neighbouring plants. This study reports further studies of the reported effect of cress (Lepidium sativum) seed(ling) exudates on seedling growth in Amaranthus caudatus and Lactuca sativa. In the presence of live cress seedlings, both species grew longer hypocotyls and shorter roots than cress-free controls. The effects of cress seedlings were allelopathic and not due to competition for resources. Amaranthus seedlings grown in the presence of cress allelochemical(s) had longer, thinner hypocotyls and shorter, thicker roots--effects previously attributed to lepidimoide. The active principle was more abundant in cress seed exudate than in seedling (root) exudates. It was present in non-imbibed seeds and releasable from heat-killed seeds. Release from live seeds was biphasic, starting rapidly but then continuing gradually for 24 h. The active principle was generated by aseptic cress tissue and was not a microbial digestion product or seed-treatment chemical. Crude seed exudate affected hypocotyl and root growth at ~25 and ~450 μg ml(-1) respectively. The exudate slightly (28%) increased epidermal cell number along the length of the Amaranthus hypocotyl but increased total hypocotyl elongation by 129%; it resulted in a 26% smaller hypocotyl circumference but a 55% greater epidermal cell number counted round the circumference. Therefore, the effect of the allelochemical(s) on organ morphology was imposed primarily by regulation of cell expansion, not cell division. It is concluded that cress seeds exude endogenous substances, probably including lepidimoide, that principally regulate cell expansion in receiver plants.

  17. Comparing the epidermal growth factor interaction with four different cell lines: intriguing effects imply strong dependency of cellular context.

    Directory of Open Access Journals (Sweden)

    Hanna Björkelund

    Full Text Available The interaction of the epidermal growth factor (EGF with its receptor (EGFR is known to be complex, and the common over-expression of EGF receptor family members in a multitude of tumors makes it important to decipher this interaction and the following signaling pathways. We have investigated the affinity and kinetics of (125I-EGF binding to EGFR in four human tumor cell lines, each using four culturing conditions, in real time by use of LigandTracer®.Highly repeatable and precise measurements show that the overall apparent affinity of the (125I-EGF - EGFR interaction is greatly dependent on cell line at normal culturing conditions, ranging from K(D ≈ 200 pM on SKBR3 cells to K(D≈8 nM on A431 cells. The (125I-EGF - EGFR binding curves (irrespective of cell line have strong signs of multiple simultaneous interactions. Furthermore, for the cell lines A431 and SKOV3, gefitinib treatment increases the (125I-EGF - EGFR affinity, in particular when the cells are starved. The (125I-EGF - EGFR interaction on cell line U343 is sensitive to starvation while as on SKBR3 it is insensitive to gefitinib and starvation.The intriguing pattern of the binding characteristics proves that the cellular context is important when deciphering how EGF interacts with EGFR. From a general perspective, care is advisable when generalizing ligand-receptor interaction results across multiple cell-lines.

  18. Probiotics-pathogen interactions elicit differential regulation of cutaneous immune responses in epidermal cells of Atlantic cod Gadus morhua.

    Science.gov (United States)

    Lazado, Carlo C; Caipang, Christopher Marlowe A

    2014-01-01

    Little is known on the cutaneous immune responses during probiotics-pathogen interactions in fish. Thus, this study employed Atlantic cod primary epidermal (EP) cell cultures as a model to understand this interaction. The probiotics-pathogen interactions in the EP cell cultures were elucidated using Vibrio anguillarum 2133 (VA) as the pathogen and two host-derived bacteria (GP21 and GP12) as the probiotics. There was a regional size difference on the EP cells; i.e., EP cells from the dorsal region were significantly larger than the EP cells at the ventral side. VA significantly decreased viability of EP cells. In the presence of probiotics, this inhibition was mitigated. The probiotics reduced VA-induced cellular apoptosis and the probiotics-pathogen interactions influenced cellular myeloperoxidase activity during the latter stage of co-incubation. The probiotics-pathogen interactions triggered differential regulation of immune-related genes and the effects of the interaction were dependent on the region where the cells were isolated and the length of the co-incubation period. In most cases, the presence of probiotics alone showed no significant change on the mRNA level of immune genes in the EP cells but triggered immunostimulatory activity when incubated with VA. This study showed that the virulence of VA in EP cells could be modulated by host-derived probiotics and the immunomodulatory characteristics of the two candidate probionts advanced their immune-related probiotic potential.

  19. Altered growth, differentiation, and responsiveness to epidermal growth factor of human embryonic mesenchymal cells of palate by persistent rubella virus infection.

    OpenAIRE

    Yoneda, T.; Urade, M; Sakuda, M.; Miyazaki, T

    1986-01-01

    We previously demonstrated that human embryonic mesenchymal cells derived from the palate (HEMP cells) retain alkaline phosphatase (ALP) content and capacity for collagen synthesis after long-term culture, and their growth is markedly stimulated by epidermal growth factor (EGF). There was a dramatic decrease in ALP content and capacity to synthesize collagen in HEMP cells (HEMP-RV cells) persistently infected with rubella virus (RV). EGF increased ALP activity and decreased collagen synthesis...

  20. Inhibition of invasiveness and expression of epidermal growth factor receptor in human colorectal carcinoma cells induced by retinoic acid

    Institute of Scientific and Technical Information of China (English)

    SUNBAODONG; JINDANSONG

    1995-01-01

    Human amniotic basement membrane (HABM) model and agarose drop explant method were used to investigate the effects of retinoic acid(RA) on the invasive ness and adhesiveness to the basement membrane,and the migration of a highly invasive human colorectal cancer cell line CCL229.Results showed that 5×106 MRA markedly reduced the in vitro invasiveness and adhesiveness to the HABM,and the migration of the CCL229 cells.In addition,to elucidate the relation between expression of epidermal growth factor receptor(EGFR) and the invasiveness of the colorectal carcinoma cells,two well-differentiated,but with different invasiveness colorectal cancer cell lines were compared at mRNA level for expression of EGFR by using EGFR cDNA probe labeled with digoxigenin(DIG). Expression of EGFR was shown to be markedly higher in the highly invassive CCL229 cells than that in the low invasive CX-1 cells.Furthermore,expression of EGFR in RA treated CCL229 cells gradually decreased with time,the level being the lowest on day 6 of the RA treatment.

  1. The influence of Tribenoside on expression and deposition of epidermal laminins in HaCaT cells.

    Science.gov (United States)

    Kikkawa, Yamato; Takaki, Shu; Matsuda, Yuji; Okabe, Koichi; Taniguchi, Masakazu; Oomachi, Kengo; Samejima, Teruyuki; Katagiri, Fumihiko; Hozumi, Kentaro; Nomizu, Motoyoshi

    2010-01-01

    Tribenoside has been used clinically for hemorrhoidal disease associated with coagulation, inflammation, and wounds. However, the pharmacological mechanism of tribenoside activity has never been clear. In this study we examined whether tribenoside affected expression and deposition of laminins that are required for reconstruction of basement membranes (BMs) during wound healing in hemorrhoidal disease. HaCaT cells, which are derived from human epidermis, were treated in growth media supplemented with tribenoside. Reverse transcriptase-polymerase chain reaction (RT-PCR) using primers specific for laminin chains showed that HaCaT cells constitutively expressed laminin alpha3, alpha5, beta1, beta3, gamma1, and gamma2 chains. Tribenoside treatment of HaCaT cells did not induce expression of other laminin chains. We also quantified the expression of laminin chains in tribenoside-treated cells using real-time PCR. The expression level of laminin alpha3, beta1, beta3, gamma1, and gamma2 chains was not affected. In contrast, the expression of laminin alpha5 in the tribenoside-treated cells was four times higher than that of control cells. Immunocytochemistry also showed that tribenoside accelerated the focal deposition of laminin-332 (alpha3, beta3, gamma2). These results suggest that tribenoside interacts with epidermal cells and regulates the expression and localization of laminins to help reconstruct BMs in wound healing of hemorrhoids.

  2. A DTC niche plexus surrounds the germline stem cell pool in Caenorhabditis elegans.

    Science.gov (United States)

    Byrd, Dana T; Knobel, Karla; Affeldt, Katharyn; Crittenden, Sarah L; Kimble, Judith

    2014-01-01

    The mesenchymal distal tip cell (DTC) provides the niche for Caenorhabditis elegans germline stem cells (GSCs). The DTC has a complex cellular architecture: its cell body caps the distal gonadal end and contacts germ cells extensively, but it also includes multiple cellular processes that extend along the germline tube and intercalate between germ cells. Here we use the lag-2 DTC promoter to drive expression of myristoylated GFP, which highlights DTC membranes and permits a more detailed view of DTC architecture. We find that short processes intercalating between germ cells contact more germ cells than seen previously. We define this region of extensive niche contact with germ cells as the DTC plexus. The extent of the DTC plexus corresponds well with the previously determined extent of the GSC pool. Moreover, expression of a differentiation marker increases as germ cells move out of the plexus. Maintenance of this DTC plexus depends on the presence of undifferentiated germ cells, suggesting that germ cell state can influence niche architecture. The roles of this DTC architecture remain an open question. One idea is that the DTC plexus delivers Notch signaling to the cluster of germ cells comprising the GSC pool; another idea is that the plexus anchors GSCs at the distal end.

  3. Effects of NaCl and Ca2+on Membrane Potential of Epidermal Cells of Maize Roots

    Institute of Scientific and Technical Information of China (English)

    HUA Jia-min; WANG Xiao-li; ZHAI Fu-qin; YAN Feng; FENG Ke

    2008-01-01

    The effects of salt-stress on plants involve not only the water stress caused by low osmotic pressure,but also the toxicity of excess Na+.A large amount of Na+ entering cells would reduce K+ uptake,which leads to an imbalance of K:Na ratio in cells.One of the reasons for the reduced K+-uptake iS the closure of K+-channel which is controlled by membrane potential.Calcium is usually applied to improve the growth of plants on saline soils and shows positive influence in the integrality of cell membrane.This study applied glass microelectrode technique to monitoring the NaCl-induced changes of membrane potential of root epidermal cells of maize(Zea mays L.,Denghai 11)seedlings at NaCl concentrations of 0,8,20,50,100,200 mmol L-1,respectively.The effect of Ca2+ on the changes of membrane potential caused by NaCl Was also studied.The results showed that:NaCl caused cell membrane depolarization.The depolarization became greater and faster with increasing of NaCl concentration.Moreover,the extent of depolarization was positively correlated with NaCl concentration.The addition of calcium postponed the depolarization,and decreased the degree of depolarization caused by NaCl.High NaCl concentration leads to depolarization of maize root cell membrane,which can partly be counteracted by calcium.

  4. Role of iron in inactivation of epidermal growth factor receptor after asbestos treatment of human lung and pleural target cells.

    Science.gov (United States)

    Baldys, Aleksander; Aust, Ann E

    2005-05-01

    Although the mechanism by which asbestos causes cancer remains unknown, iron associated with asbestos is thought to play a role in the pathogenic effects of fibers. Here, we examined the effects of asbestos on the epidermal growth factor receptor (EGFR) in human lung epithelial (A549) cells, human pleural mesothelial (MET5A) cells, and normal human small airway epithelial (SAEC) cells. Treatment of A549, MET5A, and SAEC cells with asbestos caused a significant reduction of EGFR tyrosine phosphorylation. This was both time- (15 min to 24 h) and concentration-dependent (1.5, 3, and 6 mug/cm(2)) in A549 cells. Also, treatment with 6 mug/cm(2) crocidolite for 24 h diminished the phosphorylation levels of human EGFR 2 (HER2). Exposure of A549 cells to 6 mug/cm(2) crocidolite for 3-24 h resulted in no detectable Y1045 phosphorylation and no apparent degradation of the EGFR. Inhibition of fiber endocytosis resulted in a considerable inhibition of EGFR dephosphorylation. Removal of iron from asbestos by desferrioxamine B or phytic acid inhibited asbestos-induced decreases in EGFR phosphorylation. The effects of crocidolite, amosite, and chrysotile on the EGFR phosphorylation state appeared to be directly related to the amount of iron mobilized from these fibers. These results strongly suggest that iron plays an important role in asbestos-induced inactivation of EGFR.

  5. Third-Generation Tyrosine Kinase Inhibitors Targeting Epidermal Growth Factor Receptor Mutations in Non-Small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Tristan A. Barnes

    2017-05-01

    Full Text Available Sensitizing mutations in the epidermal growth factor receptor (EGFR predict response to EGFR tyrosine kinase inhibitors (TKIs and both first- and second-generation TKIs are available as first-line treatment options in patients with advanced EGFR-mutant non-small cell lung cancer. Eventual resistance develops with multiple mechanisms identifiable both upon repeat biopsy and in plasma circulating tumor DNA. The T790M gatekeeper mutation is responsible for almost 60% of cases. A number of third-generation TKIs are in clinical development, and osimertinib has been approved by the US Food and Drug Administration for the treatment of patients with EGFR T790M mutant lung cancer after failure of initial EGFR kinase therapy. Resistance mechanisms are being identified to these novel agents, and the treatment landscape of EGFR-mutant lung cancer continues to evolve. The sequence of EGFR TKIs may change in the future and combination therapies targeting resistance appear highly promising.

  6. Third-Generation Tyrosine Kinase Inhibitors Targeting Epidermal Growth Factor Receptor Mutations in Non-Small Cell Lung Cancer.

    Science.gov (United States)

    Barnes, Tristan A; O'Kane, Grainne M; Vincent, Mark David; Leighl, Natasha B

    2017-01-01

    Sensitizing mutations in the epidermal growth factor receptor (EGFR) predict response to EGFR tyrosine kinase inhibitors (TKIs) and both first- and second-generation TKIs are available as first-line treatment options in patients with advanced EGFR-mutant non-small cell lung cancer. Eventual resistance develops with multiple mechanisms identifiable both upon repeat biopsy and in plasma circulating tumor DNA. The T790M gatekeeper mutation is responsible for almost 60% of cases. A number of third-generation TKIs are in clinical development, and osimertinib has been approved by the US Food and Drug Administration for the treatment of patients with EGFR T790M mutant lung cancer after failure of initial EGFR kinase therapy. Resistance mechanisms are being identified to these novel agents, and the treatment landscape of EGFR-mutant lung cancer continues to evolve. The sequence of EGFR TKIs may change in the future and combination therapies targeting resistance appear highly promising.

  7. Effect of epidermal growth factor on follicle-stimulating hormone-induced proliferation of granulosa cells from chicken prehierarchical follicles

    Institute of Scientific and Technical Information of China (English)

    Jin-xing LIN; Yu-dong JIA; Cai-qiao ZHANG

    2011-01-01

    The development of ovarian follicular cells is controlled by multiple circulating and local hormones and factors,including follicle-stimulating hormone (FSH) and epidermal growth factor (EGF).In this study,the stagespecific effect of EGF on FSH-induced proliferation of granulosa cells was evaluated in the ovarian follicles of egg-laying chickens.Results showed that EGF and its receptor (EGFR) mRNAs displayed a high expression in granulosa cells from the prehierarchical follicles,including the large white follicle (LWF) and small yellow follicle (SYF),and thereafter the expression decreased markedly to the stage of the largest preovulatory follicle.SYF represents a turning point of EGF/EGFR mRNA expression during follicle selection.Subsequently the granulosa cells from SYF were cultured to reveal the mediation of EGF in FSH action.Cell proliferation was remarkably increased by treatment with either EGF or FSH (0.1-100 ng/ml).This result was confirmed by elevated proliferating cell nuclear antigen (PCNA) expression and decreased cell apoptosis.Furthermore,EGF-induced cell proliferation was accompanied by increased mRNA expressions of EGFR,FSH receptor,and the cell cycle-regulating genes (cyclins D1 and E1,cyclin-dependent kinases 2 and 6) as well as decreased expression of luteinizing hormone receptor mRNA.However,the EGF or FSH-elicited effect was reversed by simultaneous treatment with an EGFR inhibitor AG1478.In conclusion,EGF and EGFR expressions manifested stage-specific changes during follicular development and EGF mediated FSH-induced cell proliferation and retarded cell differentiation in the prehierarchical follicles.These expressions thus stimulated follicular growth before selection in the egg-laying chicken.

  8. Oligomerization of epidermal growth factor receptors (EGFR) on A431 cells studied by time-resolved fluorescence imaging microscopy: a stereochemical model for tyrosine kinase receptor activation

    NARCIS (Netherlands)

    Gadella, Th.W.J.; Jovin, T.M.

    1995-01-01

    The aggregation states of the epidermal growth factor receptor (EGFR) on single A431 human epidermoid carcinoma cells were assessed with two new techniques for determining fluorescence resonance en- ergy transfer: donor photobleaching fluorescence reso- nance energy transfer (pbFRET) microscopy and

  9. MATRIX METALLOPROTEINS (MMP)-MEDIATED PHOSPHORYLATION OF THE EPIDERMAL GROWTH FACTOR RECEPTOR (EGFR) IN HUMAN AIRWAY EPITHELIAL CELLS (HAEC) EXPOSED TO ZINC (ZN)

    Science.gov (United States)

    Matrix Metalloproteinase (MMP)-Mediated Phosphorylation of The Epidermal Growth Factor Receptor (EGFR) in Human Airway Epithelial Cells (HAEC) Exposed to Zinc (Zn)Weidong Wu, James M. Samet, Robert Silbajoris, Lisa A. Dailey, Lee M. Graves, and Philip A. BrombergCenter fo...

  10. Oligomerization of epidermal growth factor receptors (EGFR) on A431 cells studied by time-resolved fluorescence imaging microscopy: a stereochemical model for tyrosine kinase receptor activation

    NARCIS (Netherlands)

    Th.W.J. Gadella; T.M. Jovin

    1995-01-01

    The aggregation states of the epidermal growth factor receptor (EGFR) on single A431 human epidermoid carcinoma cells were assessed with two new techniques for determining fluorescence resonance en- ergy transfer: donor photobleaching fluorescence reso- nance energy transfer (pbFRET) microscopy and

  11. miR-134 inhibits non-small cell lung cancer growth by targeting the epidermal growth factor receptor.

    Science.gov (United States)

    Qin, Qin; Wei, Furong; Zhang, Jianbo; Wang, Xingwu; Li, Baosheng

    2016-10-01

    The epidermal growth factor receptor (EGFR) is frequently activated in a wide range of solid tumours and represents an important therapeutic target. MicroRNAs (miRNAs) have recently been recognized as a rational and potential modality for anti-EGFR therapies. However, more EGFR-targeting miRNAs need to be explored. In this study, we identified a novel EGFR-targeting miRNA, miRNA-134 (miR-134), in non-small-cell lung cancer (NSCLC) cell lines. Luciferase assays confirmed that EGFR is a direct target of miR-134. In addition, the overexpression of miR-134 inhibited EGFR-related signaling and suppressed NSCLC cells proliferation by inducing cell cycle arrest and/or apoptosis, suggesting that miR-134 functions as a tumour suppressor in NSCLC. Further mechanistic investigation including RNAi and rescue experiments suggested that the down-regulation of EGFR by miR-134 partially contributes to the antiproliferative role of miR-134. Last, in vivo experiments demonstrated that miR-134 suppressed tumour growth of A549 xenograft in nude mice. Taken together, our findings suggest that miR-134 inhibits non-small cell lung cancer growth by targeting the EGFR.

  12. CD147, CD44, and the epidermal growth factor receptor (EGFR) signaling pathway cooperate to regulate breast epithelial cell invasiveness.

    Science.gov (United States)

    Grass, G Daniel; Tolliver, Lauren B; Bratoeva, Momka; Toole, Bryan P

    2013-09-06

    The immunoglobulin superfamily glycoprotein CD147 (emmprin; basigin) is associated with an invasive phenotype in various types of cancers, including malignant breast cancer. We showed recently that up-regulation of CD147 in non-transformed, non-invasive breast epithelial cells is sufficient to induce an invasive phenotype characterized by membrane type-1 matrix metalloproteinase (MT1-MMP)-dependent invadopodia activity (Grass, G. D., Bratoeva, M., and Toole, B. P. (2012) Regulation of invadopodia formation and activity by CD147. J. Cell Sci. 125, 777-788). Here we found that CD147 induces breast epithelial cell invasiveness by promoting epidermal growth factor receptor (EGFR)-Ras-ERK signaling in a manner dependent on hyaluronan-CD44 interaction. Furthermore, CD147 promotes assembly of signaling complexes containing CD147, CD44, and EGFR in lipid raftlike domains. We also found that oncogenic Ras regulates CD147 expression, hyaluronan synthesis, and formation of CD147-CD44-EGFR complexes, thus forming a positive feedback loop that may amplify invasiveness. Last, we showed that malignant breast cancer cells are heterogeneous in their expression of surface-associated CD147 and that high levels of membrane CD147 correlate with cell surface EGFR and CD44 levels, activated EGFR and ERK1, and activated invadopodia. Future studies should evaluate CD147 as a potential therapeutic target and disease stratification marker in breast cancer.

  13. Calcium-dependent depletion zones in the cortical microtubule array coincide with sites of, but do not regulate, wall ingrowth papillae deposition in epidermal transfer cells

    OpenAIRE

    Zhang, Hui-Ming; Talbot, Mark J.; McCurdy, David W.; Patrick, John W.; Offler, Christina E.

    2015-01-01

    Trans-differentiation to a transfer-cell morphology is characterized by the localized deposition of wall ingrowth papillae that protrude into the cytosol. Whether the cortical microtubule array directs wall ingrowth papillae formation was investigated using a Vicia faba cotyledon culture system in which their adaxial epidermal cells were spontaneously induced to trans-differentiate to transfer cells. During deposition of wall ingrowth papillae, the aligned cortical microtubule arrays in precu...

  14. Titanium implant impairment and surrounding muscle cell death following neuro-myoelectrostimulation: An in vivo study.

    Science.gov (United States)

    Lecocq, Mathieu; Félix, Marie-Solenne; Linares, Jean-Marc; Chaves-Jacob, Julien; Decherchi, Patrick; Dousset, Erick

    2015-11-01

    Electrical currents have deleterious effects on biomedical metallic implants. However, following arthroplasty, neuro-myoelectrostimulation (NMES) is often used in patient rehabilitation. Such a rehabilitation technique could compromise patient recovery through deleterious effects on metallic alloys and biological tissues. The purpose of our study was to assess the effects of NMES on a Ti6Al4V implant placed in a rat tibial crest and the surrounding muscle tissues. This in vivo study allowed to bring to the fore the prosthesis behavior under mechanical and electromagnetic loads induced by NEMS stimulation. After 3 weeks, implant-to-bone adhesion significantly decreased in stimulated animals compared with nonstimulated animals. Surface mapping indicated titanium implant degradation after NMES. Furthermore, NMES alone did not induce muscle damage contrary to that found in implanted animals. The muscle damage rate was significantly higher in implanted and stimulated animals compared with implanted-only animals. It seems obvious that rehabilitation programs using the NMES technique could induce early deterioration of biomaterial employed for surgical implants. Clinicians should reconsider the use of NMES as a rehabilitation technique for patients with titanium prostheses.

  15. S100A7-downregulation inhibits epidermal growth factor-induced signaling in breast cancer cells and blocks osteoclast formation.

    Directory of Open Access Journals (Sweden)

    Vikram Paruchuri

    Full Text Available S100A7 is a small calcium binding protein, which has been shown to be differentially expressed in psoriatic skin lesions, as well as in squamous cell tumors of the skin, lung and breast. Although its expression has been correlated to HER+ high-grade tumors and to a high risk of progression, the molecular mechanisms of these S100A7-mediated tumorigenic effects are not well known. Here, we showed for the first time that epidermal growth factor (EGF induces S100A7 expression in both MCF-7 and MDA-MB-468 cell lines. We also observed a decrease in EGF-directed migration in shRNA-downregulated MDA-MB-468 cell lines. Furthermore, our signaling studies revealed that EGF induced simultaneous EGF receptor phosphorylation at Tyr1173 and HER2 phosphorylation at Tyr1248 in S100A7-downregulated cell lines as compared to the vector-transfected controls. In addition, reduced phosphorylation of Src at tyrosine 416 and p-SHP2 at tyrosine 542 was observed in these downregulated cell lines. Further studies revealed that S100A7-downregulated cells had reduced angiogenesis in vivo based on matrigel plug assays. Our results also showed decreased tumor-induced osteoclastic resorption in an intra-tibial bone injection model involving SCID mice. S100A7-downregulated cells had decreased osteoclast number and size as compared to the vector controls, and this decrease was associated with variations in IL-8 expression in in vitro cell cultures. This is a novel report on the role of S100A7 in EGF-induced signaling in breast cancer cells and in osteoclast formation.

  16. Epidermal growth factor mediates detachment from and invasion through collagen I and Matrigel in Capan-1 pancreatic cancer cells

    Directory of Open Access Journals (Sweden)

    Kuver Rahul

    2005-03-01

    Full Text Available Abstract Background Pancreatic adenocarcinoma is a highly invasive neoplasm. Epidermal growth factor (EGF and its receptor are over expressed in pancreatic cancer, and expression correlates with invasion and metastasis. We hypothesized that EGF receptor and integrin signalling pathways interact in mediating cellular adhesion and invasion in pancreatic cancer, and that invasiveness correlates temporally with detachment from extracellular matrix. Methods We tested this hypothesis by investigating the role of EGF in mediating adhesion to and invasion through collagen I and Matrigel in the metastatic pancreatic adenocarcinoma cell line Capan-1. Adhesion and invasion were measured using in vitro assays of fluorescently-labeled cells. Adhesion and invasion assays were also performed in the primary pancreatic adenocarcinoma cell line MIA PaCa-2. Results EGF inhibited adhesion to collagen I and Matrigel in Capan-1 cells. The loss of adhesion was reversed by AG825, an inhibitor of erbB2 receptor signalling and by wortmannin, a PI3K inhibitor, but not by the protein synthesis inhibitor cycloheximide. EGF stimulated invasion through collagen I and Matrigel at concentrations and time courses similar to those mediating detachment from these extracellular matrix components. Adhesion to collagen I was different in MIA PaCa-2 cells, with no significant change elicited following EGF treatment, whereas treatment with the EGF family member heregulin-alpha elicited a marked increase in adhesion. Invasion through Matrigel in response to EGF, however, was similar to that observed in Capan-1 cells. Conclusion An inverse relationship exists between adhesion and invasion capabilities in Capan-1 cells but not in MIA PaCa-2 cells. EGF receptor signalling involving the erbB2 and PI3K pathways plays a role in mediating these events in Capan-1 cells.

  17. Simultaneous blockade of the epidermal growth factor receptor/mammalian target of rapamycin pathway by epidermal growth factor receptor inhibitors and rapamycin results in reduced cell growth and survival in biliary tract cancer cells.

    Science.gov (United States)

    Herberger, Beata; Berger, Walter; Puhalla, Harald; Schmid, Katharina; Novak, Sabine; Brandstetter, Anita; Pirker, Christine; Gruenberger, Thomas; Filipits, Martin

    2009-06-01

    The prognosis of patients with biliary tract adenocarcinomas (BTA) is still poor due to lack of effective systemic treatment options. Knowledge of the molecular mechanisms involved in the pathogenesis of this disease is of importance for the development of new treatment strategies. We determined the expression of epidermal growth factor receptor (EGFR) and activated mammalian target of rapamycin (p-mTOR) in paraffin-embedded surgical specimens of BTA (n = 89) by immunohistochemistry. Overall survival was analyzed with Cox models adjusted for clinical and pathologic factors. Combined EGFR/p-mTOR expression was significantly associated with relapse-free survival [adjusted hazard ratio for relapse, 2.20; 95% confidence interval (95% CI), 1.45-3.33; P BTA cell lines was tested in short-term 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays and long-term colony formation assays. Simultaneous blockade of EGFR and mTOR in biliary tract cancer cell lines results in a synergistic inhibition of both phosphatidylinositol-3-kinase and mitogen-activated protein kinase pathways, leading to reduced cell growth and survival. These results suggest that combined targeted therapy with EGFR and mTOR inhibitors may potentially benefit patients with BTAs and should be further evaluated in clinical trials.

  18. Epidermal growth factor receptor intron-1 polymorphism predicts gefitinib outcome in advanced non-small cell lung cancer.

    Science.gov (United States)

    Tiseo, Marcello; Capelletti, Marzia; De Palma, Giuseppe; Franciosi, Vittorio; Cavazzoni, Andrea; Mozzoni, Paola; Alfieri, Roberta R; Goldoni, Matteo; Galetti, Maricla; Bortesi, Beatrice; Bozzetti, Cecilia; Loprevite, Maura; Boni, Luca; Camisa, Roberta; Rindi, Guido; Petronini, Pier Giorgio; Ardizzoni, Andrea

    2008-10-01

    Epidermal growth factor receptor (EGFR) gene intron 1 contains a polymorphic single sequence dinucleotide repeat (CA)n whose length has been found to inversely correlate with transcriptional activity. This study was designed to assess the role of (CA)n polymorphism in predicting the outcome of gefitinib treatment in advanced non-small cell lung cancer (NSCLC). Blood and tumor tissue from 58 patients with advanced NSCLC submitted to gefitinib were collected. EGFR intron 1 gene polymorphism, along with EGFR gene mutation, gene copy number and immunohistochemistry expression were determined. Moreover, a panel of lung cancer cell lines characterized for EGFR intron 1 polymorphism was also studied. EGFR intron 1 polymorphism showed a statistically significant correlation with the gefitinib response (response rate 25 versus 0%, for patients with a (CA)16 and with a (CA)else genotype, respectively; p = 0.044). Patients with a (CA)16 genotype had a longer survival compared with those with a (CA)else genotype (11.4 versus 4.8 months, respectively; p = 0.037). In addition, cell lines lacking the (CA)16 allele showed a statistically significant higher IC50 compared with cell lines bearing at least one (CA)16 allele (p = 0.003). This study supports a potential role of EGFR intron 1 polymorphism in predicting the outcome of gefitinib treatment in advanced NSCLC.

  19. Control of patterns of symmetric cell division in the epidermal and cortical tissues of the Arabidopsis root.

    Science.gov (United States)

    Zhang, Yanwen; Iakovidis, Michail; Costa, Silvia

    2016-03-15

    Controlled cell division is central to the growth and development of all multicellular organisms. Within the proliferating zone of the Arabidopsis root, regular symmetric divisions give rise to patterns of parallel files of cells, the genetic basis of which remains unclear. We found that genotypes impaired in the TONNEAU1a (TON1a) gene display misoriented symmetric divisions in the epidermis and have no division defects in the underlying cortical tissue. The TON1a gene encodes a microtubule-associated protein. We show that in the ton1a mutant, epidermal and cortical cells do not form narrow, ring-like preprophase bands (PPBs), which are plant-specific, cytoskeletal structures that predict the position of the division plane before mitosis. The results indicate that in the cortex but not in the epidermis, division plane positioning and patterning can proceed correctly in the absence of both a functional TON1a and PPB formation. Differences between tissues in how they respond to the signals that guide symmetric division orientation during patterning might provide the basis for organised organ growth in the absence of cell movements.

  20. Epidermal growth factor regulation in adult rat alveolar type II cells of amiloride-sensitive cation channels.

    Science.gov (United States)

    Kemp, P J; Borok, Z; Kim, K J; Lubman, R L; Danto, S I; Crandall, E D

    1999-12-01

    Using the patch-clamp technique, we studied the effects of epidermal growth factor (EGF) on whole cell and single channel currents in adult rat alveolar epithelial type II cells in primary culture in the presence or absence of EGF for 48 h. In symmetrical sodium isethionate solutions, EGF exposure caused a significant increase in the type II cell whole cell conductance. Amiloride (10 microM) produced approximately 20-30% inhibition of the whole cell conductance in both the presence and absence of EGF, such that EGF caused the magnitude of the amiloride-sensitive component to more than double. Northern analysis showed that alpha-, beta- and gamma-subunits of rat epithelial Na(+) channel (rENaC) steady-state mRNA levels were all significantly decreased by EGF. At the single channel level, all active inside-out patches demonstrated only 25-pS channels that were amiloride sensitive and relatively nonselective for cations (P(Na(+))/P(K(+)) approximately 1.0:0.48). Although the biophysical characteristics (conductance, open-state probability, and selectivity) of the channels from EGF-treated and untreated cells were essentially identical, channel density was increased by EGF; the modal channel per patch was increased from 1 to 2. These findings indicate that EGF increases expression of nonselective, amiloride-sensitive cation channels in adult alveolar epithelial type II cells. The contribution of rENaC to the total EGF-dependent cation current under these conditions is quantitatively less important than that of the nonselective cation channels in these cells.

  1. Characterization and radiosensitivity of fibroblasts derived from squamous cell carcinomas of the head and neck, and the surrounding oral mucosa

    Energy Technology Data Exchange (ETDEWEB)

    Stausboel-Groen, B.; Moeller Bentzen, S. [Danish Cancer Society, Aarhus (Denmark). Dept. of Experimental Clinical Oncology; Overgaard, J. [Danish Cancer Society, Aarhus (Denmark). Dept. of Experimental Clinical Oncology]|[Danish Cancer Society, Aarhus (Denmark). Dept. of Oncology

    1998-12-31

    Recently, extensive stromal fibroblast contamination has been reported in the modified Courtenay-Mills soft agar clonogenic assay for cellular in vitro radiosensitivity in tumour biopsies. The aim of the present study was to evaluate the hypothesis that an immunocytochemical analysis added to the modified Courtenay-Mills soft agar clonogenic assay provides a measure of both fibroblast and tumour cell radiosensitivity. Therefore, fibroblast derived from squamos cell carcinomas of the head and neck, and from the surrounding oral mucosa were compared for immunocytochemistry, DNA ploidy, plating efficiency and surviving fraction of cells after a radiation dose of 2 Gy. The results of our study suggest that the stromal fibroblast derived from tumour biopsies are representative of normal fibroblasts with respect to the characteristics examined using mucosal fibroblasts as normal controls. (orig.)

  2. A randomized trial comparing ReCell system of epidermal cells delivery versus classic skin grafts for the treatment of deep partial thickness burns.

    Science.gov (United States)

    Gravante, G; Di Fede, M C; Araco, A; Grimaldi, M; De Angelis, B; Arpino, A; Cervelli, V; Montone, A

    2007-12-01

    Our purpose was to directly compare results obtained with the ReCell system and the classic skin grafting for epidermal replacement in deep partial thickness burns. We recruited all patients with deep partial thickness burns admitted at the Burn Centre of S. Eugenio Hospital in Rome over 2 years. Enrollment was conducted with a controlled strategy--sampling chart--that allowed homogeneous groups (ReCell and skin grafting) for age, gender, type of burns and total burn surface area (TBSA). We evaluated as primary endpoints of the study the (i) time for complete epithelization (both treated area and biopsy site) and (ii) aesthetic and functional quality of the epithelization (color, joint contractures). Secondary endpoints were the assessment of infections, inflammations or any adverse effects of the ReCell procedure, particular medications assumed, postoperative pain. Eighty-two patients were analyzed in two homogeneous groups. All of them received adequate epidermal replacement, but skin grafting was faster than ReCell (pskin grafting but, harvesting minor areas, can open possible future applications in the management of large-burns patients.

  3. Cell wall accumulation of fluorescent proteins derived from a trans-Golgi cisternal membrane marker and paramural bodies in interdigitated Arabidopsis leaf epidermal cells.

    Science.gov (United States)

    Akita, Kae; Kobayashi, Megumi; Sato, Mayuko; Kutsuna, Natsumaro; Ueda, Takashi; Toyooka, Kiminori; Nagata, Noriko; Hasezawa, Seiichiro; Higaki, Takumi

    2017-01-01

    In most dicotyledonous plants, leaf epidermal pavement cells develop jigsaw puzzle-like shapes during cell expansion. The rapid growth and complicated cell shape of pavement cells is suggested to be achieved by targeted exocytosis that is coordinated with cytoskeletal rearrangement to provide plasma membrane and/or cell wall materials for lobe development during their morphogenesis. Therefore, visualization of membrane trafficking in leaf pavement cells should contribute an understanding of the mechanism of plant cell morphogenesis. To reveal membrane trafficking in pavement cells, we observed monomeric red fluorescent protein-tagged rat sialyl transferases, which are markers of trans-Golgi cisternal membranes, in the leaf epidermis of Arabidopsis thaliana. Quantitative fluorescence imaging techniques and immunoelectron microscopic observations revealed that accumulation of the red fluorescent protein occurred mostly in the curved regions of pavement cell borders and guard cell ends during leaf expansion. Transmission electron microscopy observations revealed that apoplastic vesicular membrane structures called paramural bodies were more frequent beneath the curved cell wall regions of interdigitated pavement cells and guard cell ends in young leaf epidermis. In addition, pharmacological studies showed that perturbations in membrane trafficking resulted in simple cell shapes. These results suggested possible heterogeneity of the curved regions of plasma membranes, implying a relationship with pavement cell morphogenesis.

  4. Role of protein kinase C and epidermal growth factor receptor signalling in growth stimulation by neurotensin in colon carcinoma cells

    Directory of Open Access Journals (Sweden)

    Dajani Olav

    2011-10-01

    Full Text Available Abstract Background Neurotensin has been found to promote colon carcinogenesis in rats and mice, and proliferation of human colon carcinoma cell lines, but the mechanisms involved are not clear. We have examined signalling pathways activated by neurotensin in colorectal and pancreatic carcinoma cells. Methods Colon carcinoma cell lines HCT116 and HT29 and pancreatic adenocarcinoma cell line Panc-1 were cultured and stimulated with neurotensin or epidermal growth factor (EGF. DNA synthesis was determined by incorporation of radiolabelled thymidine into DNA. Levels and phosphorylation of proteins in signalling pathways were assessed by Western blotting. Results Neurotensin stimulated the phosphorylation of both extracellular signal-regulated kinase (ERK and Akt in all three cell lines, but apparently did so through different pathways. In Panc-1 cells, neurotensin-induced phosphorylation of ERK, but not Akt, was dependent on protein kinase C (PKC, whereas an inhibitor of the β-isoform of phosphoinositide 3-kinase (PI3K, TGX221, abolished neurotensin-induced Akt phosphorylation in these cells, and there was no evidence of EGF receptor (EGFR transactivation. In HT29 cells, in contrast, the EGFR tyrosine kinase inhibitor gefitinib blocked neurotensin-stimulated phosphorylation of both ERK and Akt, indicating transactivation of EGFR, independently of PKC. In HCT116 cells, neurotensin induced both a PKC-dependent phosphorylation of ERK and a metalloproteinase-mediated transactivation of EGFR that was associated with a gefitinib-sensitive phosphorylation of the downstream adaptor protein Shc. The activation of Akt was also inhibited by gefitinib, but only partly, suggesting a mechanism in addition to EGFR transactivation. Inhibition of PKC blocked neurotensin-induced DNA synthesis in HCT116 cells. Conclusions While acting predominantly through PKC in Panc-1 cells and via EGFR transactivation in HT29 cells, neurotensin used both these pathways in HCT116

  5. Selective Amplification of the Genome Surrounding Key Placental Genes in Trophoblast Giant Cells.

    Science.gov (United States)

    Hannibal, Roberta L; Baker, Julie C

    2016-01-25

    While most cells maintain a diploid state, polyploid cells exist in many organisms and are particularly prevalent within the mammalian placenta [1], where they can generate more than 900 copies of the genome [2]. Polyploidy is thought to be an efficient method of increasing the content of the genome by avoiding the costly and slow process of cytokinesis [1, 3, 4]. Polyploidy can also affect gene regulation by amplifying a subset of genomic regions required for specific cellular function [1, 3, 4]. This mechanism is found in the fruit fly Drosophila melanogaster, where polyploid ovarian follicle cells amplify genomic regions containing chorion genes, which facilitate secretion of eggshell proteins [5]. Here, we report that genomic amplification also occurs in mammals at selective regions of the genome in parietal trophoblast giant cells (p-TGCs) of the mouse placenta. Using whole-genome sequencing (WGS) and digital droplet PCR (ddPCR) of mouse p-TGCs, we identified five amplified regions, each containing a gene family known to be involved in mammalian placentation: the prolactins (two clusters), serpins, cathepsins, and the natural killer (NK)/C-type lectin (CLEC) complex [6-12]. We report here the first description of amplification at selective genomic regions in mammals and present evidence that this is an important mode of genome regulation in placental TGCs.

  6. Delivery of epidermal neural crest stem cells (EPI-NCSC) to hippocamp in Alzheimer's disease rat model.

    Science.gov (United States)

    Esmaeilzade, Banafshe; Nobakht, Maliheh; Joghataei, Mohammad Taghi; Rahbar Roshandel, Nahid; Rasouli, Homa; Samadi Kuchaksaraei, Ali; Hosseini, Seyed Mohammad; Najafzade, Nowruz; Asalgoo, Sara; Hejazian, Leila Beygom; Moghani Ghoroghi, Fatima

    2012-01-01

    Alzheimer's disease (AD) is characterized by progressive neuronal loss in hippocamp. Epidermal neural crest stem cells (EPI-NCSC) can differentiate into neurons, astrocytes and oligodendrocytes. The purpose of this study was to evaluate the effects of transplanting EPI-NCSC into AD rat model. Two weeks after induction of AD by injection of Amyloid-β1-40 into CA1 area of rat hippocamp, Y-maze and single-trial passive avoidance tests were used to show deficit of learning and memory abilities. EPI-NCSC were obtained from the vibrissa hair follicle of rat, cultured and labeled with bromodeoxyuridine. When Alzheimer was proved by behavioral tests, EPI-NCSC was transplanted into CA3 area of hippocamp in AD rat model. The staining of EPI-NCSC markers (nestin and SOX10) was done in vitro. Double-labeling immunofluorescence was performed to study survival and differentiation of the grafted cells. We showed that transplanted EPI-NCSC survive and produce many neurons and a few glial cells, presenting glial fibrillary acidic protein. Total number of granule cells in hippocamp was estimated to be more in the AD rat model with transplanted cells as compared to AD control group. We observed that rats with hippocampal damage made more errors than control rats on the Y-maze, when reward locations were reversed. Transplanted cells were migrated to all areas of hippocamp and the total number of granule cell in treatment group was equal compared to control group. Transplantation of EPI-NCSC into hippocamp might differentiate into cholinergic neurons and could cure impairment of memory in AD rat model.

  7. Downregulation of Epidermal Growth Factor Receptor Expression Contributes to α-TEA's Proapoptotic Effects in Human Ovarian Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    Ming-Chieh Shun

    2010-01-01

    Full Text Available RRR-α-tocopherol derivative α-TEA (RRR-α-tocopherol ether-linked acetic acid analog has been shown to be a potent antitumor agent both in vivo and in vitro. In this study, we investigated the effects of α-TEA on the expression of epidermal growth factor receptor (EGFR family members, ErbB1, 2 and 3, and the role of ErbB 2 and 3 in α-TEA-induced apoptosis and suppression of Akt, FLIP and survivin in the cisplatin-sensitive (A2780S and -resistant (A2780/CP70R human ovarian cancer cell lines. Data show that α-TEA's ability to induced apoptosis was associated with reduced expression of ErbB1 (cisplatin-resistant cells, 2 and 3 (both cell types and reduced levels of the phosphorylated (active form of Akt; as well as, reduced levels of FLIP and survivin proteins in both cell types. Ectopic overexpression and siRNA knockdown studies showed that ErbB2, ErbB3, Akt, FLIP and survivin are involved in α-TEA-induce apoptosis and that α-TEA downregulates FLIP and survivin via suppression of pAkt, which is mediated by ErbB2 and ErB3. Thus, α-TEA is a potent pro-apoptotic agent for both cisplatin-sensitive and -resistant ovarian cancer cell lines in cell culture and it produces cell death, at least in part, by downregulation of members of the EGFR family.

  8. Role of epidermal γδ T-cell-derived interleukin 13 in the skin-whitening effect of Ginsenoside F1.

    Science.gov (United States)

    Han, Jiyeon; Lee, Eunkyung; Kim, EunJoo; Yeom, Myung Hun; Kwon, Ohsang; Yoon, Tae Hong; Lee, Tae Ryong; Kim, Kwangmi

    2014-11-01

    Ginsenoside F1 (GF1) is a metabolite of ginsenoside Rg1. Although GF1 has several benefits for skin physiology, the effect of GF1 on skin pigmentation has not been reported. We found that a cream containing 0.1% GF1 showed a significant whitening effect on artificially tanned human skin after 8 weeks of application. However, GF1 did not inhibit mRNA expression of tyrosinase or dopachrome tautomerase (DCT) in normal human epidermal melanocytes (NHEMs) or cocultured NHEMs/normal human epidermal keratinocytes. Interestingly, GF1 enhanced production of interleukin 13 (IL-13) from human epidermal γδ T cells. IL-13 significantly reduced the mRNA expression and protein amount of both tyrosinase and DCT and reduced melanin synthesis activities in NHEMs, resulting in visible brightening of NHEM pellet. These results suggest that enhancement of IL-13 production by GF1 from epidermal γδ T cells might play a role in the skin-whitening effect of GF1 via the suppression of tyrosinase and DCT.

  9. Role of 3'-5'-cyclic adenosine monophosphate on the epidermal growth factor dependent survival in mammary epithelial cells.

    Science.gov (United States)

    Grinman, Diego Y; Romorini, Leonardo; Presman, Diego M; Rocha-Viegas, Luciana; Coso, Omar A; Davio, Carlos; Pecci, Adali

    2016-01-01

    Epidermal growth factor (EGF) has been suggested to play a key role in the maintenance of epithelial cell survival during lactation. Previously, we demonstrated that EGF dependent activation of PI3K pathway prevents apoptosis in confluent murine HC11 cells cultured under low nutrient conditions. The EGF protective effect is associated with increased levels of the antiapoptotic protein Bcl-XL. Here, we identify the EGF-dependent mechanism involved in cell survival that converges in the regulation of bcl-X expression by activated CREB. EGF induces Bcl-XL expression through activation of a unique bcl-X promoter, the P1; being not only the PI3K/AKT signaling pathway but also the increase in cAMP levels and the concomitant PKA/CREB activation necessary for both bcl-XL upregulation and apoptosis avoidance. Results presented in this work suggest the existence of a novel connection between the EGF receptor and the adenylate cyclase that would have an impact in preventing apoptosis under low nutrient conditions.

  10. Blister fluid T lymphocytes during toxic epidermal necrolysis are functional cytotoxic cells which express human natural killer (NK) inhibitory receptors

    Science.gov (United States)

    Le Cleach, L; Delaire, S; Boumsell, L; Bagot, M; Bourgault-Villada, I; Bensussan, A; Roujeau, J C

    2000-01-01

    Toxic epidermal necrolysis (TEN) is a rare life-threatening adverse drug reaction characterized by a massive destruction of the epidermis. Immunohistological studies of skin biopsies of TEN showed infiltrates of predominantly CD8+ T lymphocytes even though other authors reported a prominent involvement of cells of the monocyte-macrophage lineage. The aim of this study was to characterize phenotypically and functionally the cells present in the cutaneous blister fluid of four patients with TEN. We first determined that lymphocytes were predominant in blister fluid obtained early, while monocytes/macrophages later became the most important population. We then showed that this lymphocyte population, mainly CD3+CD8+, corresponded to a peculiar cell subset as they expressed cutaneous leucocyte antigen, killer inhibitory receptors KIR/KAR and failed to express CD28 molecule. Functionally, we determined that blister T lymphocytes had a cytotoxic T lymphocyte (CTL)- and NK-like cytotoxicity. The role of this cytotoxic lymphocyte population present at the site of lesions during TEN remains to be understood. PMID:10606987

  11. Identification of bone morphogenetic protein 7 (BMP7) as an instructive factor for human epidermal Langerhans cell differentiation

    Science.gov (United States)

    Yasmin, Nighat; Bauer, Thomas; Modak, Madhura; Wagner, Karin; Schuster, Christopher; Köffel, Rene; Seyerl, Maria; Stöckl, Johannes; Elbe-Bürger, Adelheid; Graf, Daniel

    2013-01-01

    Human Langerhans cell (LC) precursors populate the epidermis early during prenatal development and thereafter undergo massive proliferation. The prototypic antiproliferative cytokine TGF-β1 is required for LC differentiation from human CD34+ hematopoietic progenitor cells and blood monocytes in vitro. Similarly, TGF-β1 deficiency results in LC loss in vivo. However, immunohistology studies revealed that human LC niches in early prenatal epidermis and adult basal (germinal) keratinocyte layers lack detectable TGF-β1. Here we demonstrated that these LC niches express high levels of bone morphogenetic protein 7 (BMP7) and that Bmp7-deficient mice exhibit substantially diminished LC numbers, with the remaining cells appearing less dendritic. BMP7 induces LC differentiation and proliferation by activating the BMP type-I receptor ALK3 in the absence of canonical TGF-β1–ALK5 signaling. Conversely, TGF-β1–induced in vitro LC differentiation is mediated via ALK3; however, co-induction of ALK5 diminished TGF-β1–driven LC generation. Therefore, selective ALK3 signaling by BMP7 promotes high LC yields. Within epidermis, BMP7 shows an inverse expression pattern relative to TGF-β1, the latter induced in suprabasal layers and up-regulated in outer layers. We observed that TGF-β1 inhibits microbial activation of BMP7-generated LCs. Therefore, TGF-β1 in suprabasal/outer epidermal layers might inhibit LC activation, resulting in LC network maintenance. PMID:24190429

  12. Identification of bone morphogenetic protein 7 (BMP7) as an instructive factor for human epidermal Langerhans cell differentiation.

    Science.gov (United States)

    Yasmin, Nighat; Bauer, Thomas; Modak, Madhura; Wagner, Karin; Schuster, Christopher; Köffel, Rene; Seyerl, Maria; Stöckl, Johannes; Elbe-Bürger, Adelheid; Graf, Daniel; Strobl, Herbert

    2013-11-18

    Human Langerhans cell (LC) precursors populate the epidermis early during prenatal development and thereafter undergo massive proliferation. The prototypic antiproliferative cytokine TGF-β1 is required for LC differentiation from human CD34(+) hematopoietic progenitor cells and blood monocytes in vitro. Similarly, TGF-β1 deficiency results in LC loss in vivo. However, immunohistology studies revealed that human LC niches in early prenatal epidermis and adult basal (germinal) keratinocyte layers lack detectable TGF-β1. Here we demonstrated that these LC niches express high levels of bone morphogenetic protein 7 (BMP7) and that Bmp7-deficient mice exhibit substantially diminished LC numbers, with the remaining cells appearing less dendritic. BMP7 induces LC differentiation and proliferation by activating the BMP type-I receptor ALK3 in the absence of canonical TGF-β1-ALK5 signaling. Conversely, TGF-β1-induced in vitro LC differentiation is mediated via ALK3; however, co-induction of ALK5 diminished TGF-β1-driven LC generation. Therefore, selective ALK3 signaling by BMP7 promotes high LC yields. Within epidermis, BMP7 shows an inverse expression pattern relative to TGF-β1, the latter induced in suprabasal layers and up-regulated in outer layers. We observed that TGF-β1 inhibits microbial activation of BMP7-generated LCs. Therefore, TGF-β1 in suprabasal/outer epidermal layers might inhibit LC activation, resulting in LC network maintenance.

  13. Macrophage migration inhibitory factor protects from nonmelanoma epidermal tumors by regulating the number of antigen-presenting cells in skin.

    Science.gov (United States)

    Brocks, Tania; Fedorchenko, Oleg; Schliermann, Nicola; Stein, Astrid; Moll, Ute M; Seegobin, Seth; Dewor, Manfred; Hallek, Michael; Marquardt, Yvonne; Fietkau, Katharina; Heise, Ruth; Huth, Sebastian; Pfister, Herbert; Bernhagen, Juergen; Bucala, Richard; Baron, Jens M; Fingerle-Rowson, Guenter

    2017-02-01

    The response of the skin to harmful environmental agents is shaped decisively by the status of the immune system. Keratinocytes constitutively express and secrete the chemokine-like mediator, macrophage migration inhibitory factor (MIF), more strongly than dermal fibroblasts, thereby creating a MIF gradient in skin. By using global and epidermis-restricted Mif-knockout (Mif(-/-) and K14-Cre(+/tg); Mif(fl/fl)) mice, we found that MIF both recruits and maintains antigen-presenting cells in the dermis/epidermis. The reduced presence of antigen-presenting cells in the absence of MIF was associated with accelerated and increased formation of nonmelanoma skin tumors during chemical carcinogenesis. Our results demonstrate that MIF is essential for maintaining innate immunity in skin. Loss of keratinocyte-derived MIF leads to a loss of control of epithelial skin tumor formation in chemical skin carcinogenesis, which highlights an unexpected tumor-suppressive activity of MIF in murine skin.-Brocks, T., Fedorchenko, O., Schliermann, N., Stein, A., Moll, U. M., Seegobin, S., Dewor, M., Hallek, M., Marquardt, Y., Fietkau, K., Heise, R., Huth, S., Pfister, H., Bernhagen, J., Bucala, R., Baron, J. M., Fingerle-Rowson, G. Macrophage migration inhibitory factor protects from nonmelanoma epidermal tumors by regulating the number of antigen-presenting cells in skin. © FASEB.

  14. Transformation and tumor promoter sensitive phosphoproteins in JB-6 mouse epidermal cells: one is also sensitive to heat stress.

    Science.gov (United States)

    Gindhart, T D; Stevens, L; Copley, M P

    1984-09-01

    JB-6 mouse epidermal cells undergo irreversible transformation when exposed to tumor-promoting agents such as 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Phosphoprotein changes related to transformation were sought in four tumor cell lines related to JB-6 cells. Two dimensional polyacrylamide gel electrophoresis showed altered abundances of five phosphoproteins in the tumor cell lines compared with five untransformed clones. The mol. wt. in Kilodaltons and isoelectric points in pH units were: 120/6.0, 80/4.5, 55/6.5, 37/5.0 and 23-25/4.5. In all four transformants pp80 was markedly decreased and the pp23-25 doublet increased. In two of the four transformants pp120 and pp55 were increased and pp37 decreased. Treatment of untransformed clones with TPA affected only one of the phosphoproteins altered in the transformants. Treatment of untransformed clones with TPA produced a 2-fold increase in pp80 after 5 h. pp80 returned to baseline levels by 24 h and changed little in the continuous presence of TPA for up to 96 h. The increase in pp80 with short term TPA treatment occurred in all of the untransformed clones but none of four transformants. Late preneoplastic (P+) JB-6 cells only require treatment with a tumor promoter to transform. Early preneoplastic (P-) JB-6 cells require prior transfection of DNA from late preneoplastic JB-6 cells to transform in response to tumor promoter treatment. Quantitative analysis of pp80 in early preneoplastic, late preneoplastic, and tumor cell lines showed an inverse relationship between the level of pp80 and degree of preneoplastic progression in these cells. pp80 represents approximately 2% of total cellular phosphoprotein in JB-6 cells, shows microheterogeneity of both mol. wt. and isoelectric point, occurs in the particulate fraction of cells and is readily solubilized by 1% Triton. pp80 is increased by heat stress and shares other properties with the recently described mammalian heat stress protein, hsp 80. pp80's decrease in

  15. Quantitative proteomic analysis reveals effects of epidermal growth factor receptor (EGFR) on invasion-promoting proteins secreted by glioblastoma cells.

    Science.gov (United States)

    Sangar, Vineet; Funk, Cory C; Kusebauch, Ulrike; Campbell, David S; Moritz, Robert L; Price, Nathan D

    2014-10-01

    Glioblastoma multiforme is a highly invasive and aggressive brain tumor with an invariably poor prognosis. The overexpression of epidermal growth factor receptor (EGFR) is a primary influencer of invasion and proliferation in tumor cells and the constitutively active EGFRvIII mutant, found in 30-65% of Glioblastoma multiforme, confers more aggressive invasion. To better understand how EGFR contributes to tumor aggressiveness, we investigated the effect of EGFR on the secreted levels of 65 rationally selected proteins involved in invasion. We employed selected reaction monitoring targeted mass spectrometry using stable isotope labeled internal peptide standards to quantity proteins in the secretome from five GBM (U87) isogenic cell lines in which EGFR, EGFRvIII, and/or PTEN were expressed. Our results show that cell lines with EGFR overexpression and constitutive EGFRvIII expression differ remarkably in the expression profiles for both secreted and intracellular signaling proteins, and alterations in EGFR signaling result in reproducible changes in concentrations of secreted proteins. Furthermore, the EGFRvIII-expressing mutant cell line secretes the majority of the selected invasion-promoting proteins at higher levels than other cell lines tested. Additionally, the intracellular and extracellular protein measurements indicate elevated oxidative stress in the EGFRvIII-expressing cell line. In conclusion, the results of our study demonstrate that EGFR signaling has a significant effect on the levels of secreted invasion-promoting proteins, likely contributing to the aggressiveness of Glioblastoma multiforme. Further characterization of these proteins may provide candidates for new therapeutic strategies and targets as well as biomarkers for this aggressive disease. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Mechanism of murine epidermal maintenance: Cell division and the Voter Model

    CERN Document Server

    Klein, Allon M; Jones, Philip H; Simons, Benjamin D

    2007-01-01

    This paper presents an interesting experimental example of voter-model statistics in biology. In recent work on mouse tail-skin, where proliferating cells are confined to a two-dimensional layer, we showed that cells proliferate and differentiate according to a simple stochastic model of cell division involving just one type of proliferating cell that may divide both symmetrically and asymmetrically. Curiously, these simple rules provide excellent predictions of the cell population dynamics without having to address their spatial distribution. Yet, if the spatial behaviour of cells is addressed by allowing cells to diffuse at random, one deduces that density fluctuations destroy tissue confluence, implying some hidden degree of spatial regulation in the physical system. To infer the mechanism of spatial regulation, we consider a two-dimensional model of cell fate that preserves the overall population dynamics. By identifying the resulting behaviour with a three-species variation of the "Voter" model, we predi...

  17. The Epidermal Growth Factor Receptor Responsive miR-125a Represses Mesenchymal Morphology in Ovarian Cancer Cells

    Directory of Open Access Journals (Sweden)

    Karen D. Cowden Dahl

    2009-11-01

    Full Text Available The epithelial-to-mesenchymal transition (EMT that occurs during embryonic development is recapitulated during tumor metastasis. Important regulators of this process include growth factors, transcription factors, and adhesion molecules. New evidence suggests that microRNA (miRNA activity contributes to metastatic progression and EMT; however, the mechanisms leading to altered miRNA expression during cancer progression remain poorly understood. Importantly, overexpression of the epidermal growth factor receptor (EGFR in ovarian cancer correlates with poor disease outcome and induces EMT in ovarian cancer cells. We report that EGFR signaling leads to transcriptional repression of the miRNA miR-125a through the ETS family transcription factor PEA3. Overexpression of miR-125a induces conversion of highly invasive ovarian cancer cells from a mesenchymal to an epithelial morphology, suggesting miR-125a is a negative regulator of EMT. We identify AT-rich interactive domain 3B (ARID3B as a target of miR-125a and demonstrate that ARID3B is overexpressed in human ovarian cancer. Repression of miR-125a through growth factor signaling represents a novel mechanism for regulating ovarian cancer invasive behavior.

  18. A p53-dependent response limits epidermal stem cell functionality and organismal size in mice with short telomeres.

    Directory of Open Access Journals (Sweden)

    Ignacio Flores

    Full Text Available Telomere maintenance is essential to ensure proper size and function of organs with a high turnover. In particular, a dwarf phenotype as well as phenotypes associated to premature loss of tissue regeneration, including the skin (hair loss, hair graying, decreased wound healing, are found in mice deficient for telomerase, the enzyme responsible for maintaining telomere length. Coincidental with the appearance of these phenotypes, p53 is found activated in several tissues from these mice, where is thought to trigger cellular senescence and/or apoptotic responses. Here, we show that p53 abrogation rescues both the small size phenotype and restitutes the functionality of epidermal stem cells (ESC of telomerase-deficient mice with dysfunctional telomeres. In particular, p53 ablation restores hair growth, skin renewal and wound healing responses upon mitogenic induction, as well as rescues ESCmobilization defects in vivo and defective ESC clonogenic activity in vitro. This recovery of ESC functions is accompanied by a downregulation of senescence markers and an increased proliferation in the skin and kidney of telomerase-deficient mice with critically short telomeres without changes in apoptosis rates. Together, these findings indicate the existence of a p53-dependent senescence response acting on stem/progenitor cells with dysfunctional telomeres that is actively limiting their contribution to tissue regeneration, thereby impinging on tissue fitness.

  19. Proliferative activity of epidermal basal cells after wounding. AgNOR counts compared with bromodeoxyuridine reactivity in rats.

    Science.gov (United States)

    Rebolledo Godoy, A P; Rebolledo Godoy, M; Meissner, C; Oehmichen, M

    2001-04-01

    Quantitative changes in nucleolus organizer regions (NORs) are known markers of proliferation that can be demonstrated by a specific silver staining technique on paraffin-embedded sections. Wounding of skin induces proliferation of basal epidermal cells at the wound margin. The degree of proliferation depends on the survival time and can be measured by morphometric assessment of argyrophilic NORs (AgNORs). Following incision wounding of the pinnae, rats were allowed to survive for different intervals (7 rats per interval) up to 120 hours. Before each sacrifice, biopsies were taken and incubated in a bromodeoxyuridine (BrdU) solution, embedded in paraffin, and stained with an antibody against BrdU. At the same time morphometric analysis of AgNOR counts was performed on sections made from the same material. BrdU incorporating nuclei were assessed by simple counting, whereas morphometric analysis of AgNOR counts was computer aided. Both methods revealed an increase in the number of proliferating cells, a plateau phase being reached after about 36 hours, followed by a decline after about 70 hours. Both methods thus allowed a reliable temporal classification of the skin injury according to survival time. The molecular background of the AgNOR changes in relation to the proliferation of cellular elements is discussed in detail.

  20. Epidermal Growth Factor Receptor Mutation in a Patient with Squamous Cell Carcinoma of the Lung: Who Should Be Tested

    Directory of Open Access Journals (Sweden)

    Michael Schwitter

    2013-05-01

    Full Text Available We report the case of a 64-year-old ex-smoker with metastatic poorly differentiated squamous cell carcinoma (SCC of the lung and an epidermal growth factor receptor (EGFR mutation in exon 21 (p.L858R who achieved prolonged clinical benefit from treatment with an EGFR tyrosine kinase inhibitor (TKI. The initial diagnosis of SCC of the lung obtained by bronchoscopic biopsy was based on immunohistochemical staining only with positivity for cytokeratin (CK 5/6 and p63 because morphological diagnosis was not possible. Patients with non-small cell lung cancer (NSCLC, not otherwise specified (NOS favouring SCC are usually not tested for the presence of EGFR mutations, and therefore may not receive EGFR TKI therapy. A bronchoscopic rebiopsy showed small nests of undifferentiated tumour cells with weak immunoreactivity of some tumour cells for CK5/6, p63 and no positivity of some tumour cells for thyroid transcription factor-1. These findings suggested a mixed squamous/glandular immunophenotype that has been missed at the initial biopsy. Our clinical case illustrates the problem of tumour heterogeneity encountered in small bronchoscopic biopsies and the difficulties of evaluating the histological subtype in poorly differentiated carcinomas. Initial bronchoscopy should be performed by an experienced pulmonologist who attempts to obtain sufficient material from different areas of the tumour. In the era of targeted therapy, a remote smoking history in a patient with NOS favouring SCC should also lead to EGFR mutation testing to allow highly effective therapy to be offered to mutation-positive patients.

  1. Transient gibberellin application promotes Arabidopsis thaliana hypocotyl cell elongation without maintaining transverse orientation of microtubules on the outer tangential wall of epidermal cells

    KAUST Repository

    Sauret-Güeto, Susanna

    2011-11-25

    The phytohormone gibberellin (GA) promotes plant growth by stimulating cellular expansion. Whilst it is known that GA acts by opposing the growth-repressing effects of DELLA proteins, it is not known how these events promote cellular expansion. Here we present a time-lapse analysis of the effects of a single pulse of GA on the growth of Arabidopsis hypocotyls. Our analyses permit kinetic resolution of the transient growth effects of GA on expanding cells. We show that pulsed application of GA to the relatively slowly growing cells of the unexpanded light-grown Arabidopsis hypocotyl results in a transient burst of anisotropic cellular growth. This burst, and the subsequent restoration of initial cellular elongation rates, occurred respectively following the degradation and subsequent reappearance of a GFP-tagged DELLA (GFP-RGA). In addition, we used a GFP-tagged α-tubulin 6 (GFP-TUA6) to visualise the behaviour of microtubules (MTs) on the outer tangential wall (OTW) of epidermal cells. In contrast to some current hypotheses concerning the effect of GA on MTs, we show that the GA-induced boost of hypocotyl cell elongation rate is not dependent upon the maintenance of transverse orientation of the OTW MTs. This confirms that transverse alignment of outer face MTs is not necessary to maintain rapid elongation rates of light-grown hypocotyls. Together with future studies on MT dynamics in other faces of epidermal cells and in cells deeper within the hypocotyl, our observations advance understanding of the mechanisms by which GA promotes plant cell and organ growth. © 2011 Blackwell Publishing Ltd.

  2. Optical characterization of epidermal cells and their relationship to DNA recovery from touch samples [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Cristina E. Stanciu

    2015-11-01

    Full Text Available The goal of this study was to investigate the relative contributions of different cellular and genetic components to biological samples created by touch or contact with a surface – one of the most challenging forms of forensic evidence. Touch samples were generated by having individuals hold an object for five minutes and analyzed for quantity of intact epidermal cells, extracellular DNA, and DNA from pelleted cell material after elution from the collection swab. Comparisons were made between samples where individuals had washed their hands immediately prior to handling and those where hand washing was not controlled. The vast majority (84-100% of DNA detected in these touch samples was extracellular and was uncorrelated to the number of epidermal cells detected. Although little to no extracellular or cell pellet-associated DNA was detected when individuals washed their hands prior to substrate handling, we found that a significant number of epidermal cells (between ~5x103 and ~1x105 could still be recovered from these samples, suggesting that other types of biological information may be present even when no amplifiable nuclear DNA is present. These results help to elucidate the biological context for touch samples and characterize factors that may contribute to patterns of transfer and persistence of genetic material in forensic evidence.

  3. DeltaNp63alpha-mediated induction of epidermal growth factor receptor promotes pancreatic cancer cell growth and chemoresistance.

    Directory of Open Access Journals (Sweden)

    Alexey V Danilov

    Full Text Available Pancreatic ductal adenocarcinoma (PDAC is highly resistant to current chemotherapy regimens, in part due to alterations in the p53 tumor suppressor pathway. p53 homolog p63 is a transcription factor essential for the development and differentiation of epithelial surfaces. However its function in cancer is controversial and its role in PDAC is not known. We discovered that ΔNp63α was the predominantly expressed p63 variant in pancreatic cancer cell lines. ΔNp63α protein and mRNA levels were high in T3M4, BxPC3 and COLO-357 pancreatic cancer cells and low in ASPC-1 and PANC-1 cells. Overexpression of ΔNp63α in PANC-1 cells and shRNA-mediated knockdown in T3M4 cells indicated that ΔNp63α promoted anchorage-dependent and -independent growth, motility and invasion, and enhanced resistance to cisplatin-induced apoptosis. Epidermal growth factor receptor (EGFR signaling pathways contribute to the biological aggressiveness of PDAC, and we found that the motogenic effects of ΔNp63α were augmented in presence of EGF. Ectopic expression of ΔNp63α resulted in upregulation of EGFR and β1-integrin in PANC-1 cells. Conversely, ΔNp63α knockdown had an opposite effect in T3M4 cells. ΔNp63α potentiated EGF-mediated activation of ERK, Akt and JNK signaling. Chromatin immunoprecipitation and functional reporter assays demonstrated that ΔNp63α activated EGFR transcription. 14-3-3σ transcription was also positively regulated by ΔNp63α and we have previously shown that 14-3-3σ contributes to chemoresistance in pancreatic cancer cell lines. Conversely, shRNA-mediated knockdown of 14-3-3σ led to abrogation of the ΔNp63α effects on cell proliferation and invasion. Thus, p53 homolog ΔNp63α enhances the oncogenic potential of pancreatic cancer cells through trans-activation of EGFR and 14-3-3σ.

  4. Vaccinia virus infection attenuates innate immune responses and antigen presentation by epidermal dendritic cells.

    Science.gov (United States)

    Deng, Liang; Dai, Peihong; Ding, Wanhong; Granstein, Richard D; Shuman, Stewart

    2006-10-01

    Langerhans cells (LCs) are antigen-presenting cells in the skin that play sentinel roles in host immune defense by secreting proinflammatory molecules and activating T cells. Here we studied the interaction of vaccinia virus with XS52 cells, a murine epidermis-derived dendritic cell line that serves as a surrogate model for LCs. We found that vaccinia virus productively infects XS52 cells, yet this infection displays an atypical response to anti-poxvirus agents. Whereas adenosine N1-oxide blocked virus production and viral protein synthesis during a synchronous infection, cytosine arabinoside had no effect at concentrations sufficient to prevent virus replication in BSC40 monkey kidney cells. Vaccinia virus infection of XS52 cells not only failed to elicit the production of various cytokines, including tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta), IL-6, IL-10, IL-12 p40, alpha interferon (IFN-alpha), and IFN-gamma, it actively inhibited the production of proinflammatory cytokines TNF-alpha and IL-6 by XS52 cells in response to exogenous lipopolysaccharide (LPS) or poly(I:C). Infection with a vaccinia virus mutant lacking the E3L gene resulted in TNF-alpha secretion in the absence of applied stimuli. Infection of XS52 cells or BSC40 cells with the DeltaE3L virus, but not wild-type vaccinia virus, triggered proteolytic decay of IkappaBalpha. These results suggest a novel role for the E3L protein as an antagonist of the NF-kappaB signaling pathway. DeltaE3L-infected XS52 cells secreted higher levels of TNF-alpha and IL-6 in response to LPS and poly(I:C) than did cells infected with the wild-type virus. XS52 cells were productively infected by a vaccinia virus mutant lacking the K1L gene. DeltaK1L-infected cells secreted higher levels of TNF-alpha and IL-6 in response to LPS than wild-type virus-infected cells. Vaccinia virus infection of primary LCs harvested from mouse epidermis was nonpermissive, although a viral reporter protein was

  5. 小鼠表皮干细胞的分离与培养%Isolation and Cultivation of Mouse Epidermal Stem Cells

    Institute of Scientific and Technical Information of China (English)

    王丽娟; 孙耀兰; 杨雪; 王友亮; 杨晓

    2011-01-01

    Objective: To isolate and culture the mouse epidermal stem cells and analyze its capability of clone formation for further studies.Methods: The neonate mice epidermal basal cells were digested by dispase and trypsin and then seeded directly and cultivated in culture flasks without any feeder cells.The epidermal stem cells were identified by K15 and α6-integrin staining and their clone formation abilities were evaluated when they were co-cultured with mouse embryonic fibrolasts feeder cells in a cell differentiation condition.Results: The clones of neonate mice epidermal stem cells were successfully formated after 2~3 day's cultivation characterized by low nucleo-cytoplasma ratio and tiny and round shape.Those cells could be specialized marked with K15 and α6-integrin after cell passage.Conclusion: The cultivation and passage of mouse epidermal stem cells can be achieved using this kind of method.%目的:探讨体外分离和培养小鼠表皮干细胞和分析表皮干细胞克隆形成能力的方法.方法:采用中性蛋白酶和胰酶消化新生小鼠表皮基底层细胞,将细胞直接接种在细胞瓶中,在无滋养层条件下培育;利用表皮干细胞标记物K15和α6整联蛋白进行免疫荧光鉴定;以小鼠胚胎成纤维细胞作为滋养层与成年小鼠角质细胞共培养,进而分析表皮干细胞的克隆形成能力.结果:新生小鼠表皮干细胞克隆在培养2~3 d后开始形成,细胞核质较小,细胞呈小而圆的形态特征;传代后的细胞可以被K15和α6整联蛋白特异性标记.结论:利用该方法能够实现对小鼠表皮干细胞的体外培养和传代.

  6. Differential regulation of epidermal growth factor receptor by hydrogen peroxide and flagellin in cultured lung alveolar epithelial cells.

    Science.gov (United States)

    Nishi, Hiroyuki; Maeda, Noriko; Izumi, Shunsuke; Higa-Nakamine, Sayomi; Toku, Seikichi; Kakinohana, Manabu; Sugahara, Kazuhiro; Yamamoto, Hideyuki

    2015-02-05

    In previous studies, we found that stimulation of Toll-like receptor 5 (TLR5) by flagellin induced the activation of mitogen-activated protein kinase (MAPK)-activated protein kinase-2 (MAPKAPK-2) through activation of the p38 MAPK pathway in cultured alveolar epithelial A549 cells. Our studies strongly suggested that MAPKAPK-2 phosphorylated epidermal growth factor receptor (EGFR) at Ser1047. It has been reported that phosphorylation of Ser1047 after treatment with tumor necrosis factor α (TNFα) induced the internalization of EGFR. In the present study, we first found that treatment of A549 cells with hydrogen peroxide induced the activation of MAPKAPK-2 and phosphorylation of EGFR at Ser1047 within 30 min. This was different from flagellin treatment because hydrogen peroxide treatment induced the phosphorylation of EGFR at Tyr1173 as well as Ser1047, indicating the activation of EGFR. We also found that KN93, an inhibitor of CaM kinase II, inhibited the hydrogen peroxide-induced phosphorylation of EGFR at Ser1047 through inhibition of the activation of the p38 MAPK pathway. Furthermore, we examined the internalization of EGFR by three different methods. Flow cytometry with an antibody against the extracellular domain of EGFR and biotinylation of cell surface proteins revealed that flagellin, but not hydrogen peroxide, decreased the amount of cell-surface EGFR. In addition, activation of extracellular signal-regulated kinase by EGF treatment was reduced by flagellin pre-treatment. These results strongly suggested that hydrogen peroxide activated the p38 MAPK pathway via activation of CaM kinase II and that flagellin and hydrogen peroxide regulate the functions of EGFR by different mechanisms.

  7. Antitumor activity of F90,an epidermal growth factor receptor tyrosine kinase inhibitor,on glioblastoma cell line SHG-44

    Institute of Scientific and Technical Information of China (English)

    LIU Fang-jun; GUI Song-bai; LI Chu-zhong; SUN Ze-lin; ZHANG Ya-zhuo

    2008-01-01

    Background Over-expression of epidermal growth factor receptor (EGFR) is thought to be related to cell proliferation,invasion,metastasis,resistance to chemoradiotherapy and poor prognosis of various human cancers.Forty percent to fifty percent of glioblastoma multiforme (GBM) possess deregulated EGFR,which may contribute to the aggressive and refractory course of GBM.Therefore,blockade of EGFR signal transduction may be a promising treatment strategy for GBM.Methods MIT assay,cell growth curve assay and tumor xenograft model were used to evaluate the antitumor activity of F90 against SHG-44 in vitro and in vivo.Western blot assay was applied to evaluate the expression of p-EGFR,p-ERK1,p-JNK,p-P38,Bcl2 and P53 proteins.Results F90 inhibited the cell proliferation in a dose-dependent manner in vitro.The growth of SHG-44 tumor xenografts was suppressed by F90 at a high dose level (100 mg.kg-1.d-1).Phosphorylation of EGFR and activated downstream signaling proteins,such as ERK1,JNK and P38,were found to be depressed after incubation with F90 for 48 hours in vitro.Down-regulated Bcl2 protein and up-regulated P53 protein were also observed.Conclueions The results demonstrate that F90 is effective in inhibiting the proliferation of SHG-44 cells in vitro and tumor growth in vivo,suggesting that F90 may be a new therapeutic option for treatment of GBM.

  8. The Effects of Epidermal Neural Crest Stem Cells on Local Inflammation Microenvironment in the Defected Sciatic Nerve of Rats

    Directory of Open Access Journals (Sweden)

    Yue Li

    2017-05-01

    Full Text Available Cell-based therapy is a promising strategy for the repair of peripheral nerve injuries (PNIs. epidermal neural crest stems cells (EPI-NCSCs are thought to be important donor cells for repairing PNI in different animal models. Following PNI, inflammatory response is important to regulate the repair process. However, the effects of EPI-NCSCs on regulation of local inflammation microenviroment have not been investigated extensively. In the present study, these effects were studied by using 10 mm defected sciatic nerve, which was bridged with 15 mm artificial nerve composed of EPI-NCSCs, extracellular matrix (ECM and poly (lactide-co-glycolide (PLGA. Then the expression of pro- and anti-inflammatory cytokines, polarization of macrophages, regulation of fibroblasts and shwann cells (SCs were assessed by western blot, immunohistochemistry, immunofluorescence staining at 1, 3, 7 and 21 days after bridging. The structure and the function of the bridged nerve were determined by observation under light microscope and by examination of right lateral foot retraction time (LFRT, sciatic function index (SFI, gastrocnemius wet weight and electrophysiology at 9 weeks. After bridging with EPI-NCSCs, the expression of anti-inflammatory cytokines (IL-4 and IL-13 was increased, but decreased for pro-inflammatory cytokines (IL-6 and TNF-α compared to the control bridging, which was consistent with increase of M2 macrophages and decrease of M1 macrophages at 7 days after transplantation. Likewise, myelin-formed SCs were significantly increased, but decreased for the activated fibroblasts in their number at 21 days. The recovery of structure and function of nerve bridged with EPI-NCSCs was significantly superior to that of DMEM. These results indicated that EPI-NCSCs could be able to regulate and provide more suitable inflammation microenvironment for the repair of defected sciatic nerve.

  9. Interfollicular epidermal stem cells self-renew via autocrine Wnt signaling

    NARCIS (Netherlands)

    Lim, X.; Tan, S.H.; Koh, W.L.C.; Chau, R.M.W.; Yan, K.S.; Kuo, C.J.; van Amerongen, R.; Klein, A.M.; Nusse, R.

    2013-01-01

    The skin is a classical example of a tissue maintained by stem cells. However, the identity of the stem cells that maintain the interfollicular epidermis and the source of the signals that control their activity remain unclear. Using mouse lineage tracing and quantitative clonal analyses, we showed

  10. Interfollicular epidermal stem cells self-renew via autocrine Wnt signaling

    NARCIS (Netherlands)

    Lim, X.; Tan, S.H.; Koh, W.L.C.; Chau, R.M.W.; Yan, K.S.; Kuo, C.J.; van Amerongen, R.; Klein, A.M.; Nusse, R.

    2013-01-01

    The skin is a classical example of a tissue maintained by stem cells. However, the identity of the stem cells that maintain the interfollicular epidermis and the source of the signals that control their activity remain unclear. Using mouse lineage tracing and quantitative clonal analyses, we showed

  11. T Cell-Independent Mechanisms Associated with Neutrophil Extracellular Trap Formation and Selective Autophagy in IL-17A-Mediated Epidermal Hyperplasia.

    Science.gov (United States)

    Suzuki, Erika; Maverakis, Emanual; Sarin, Ritu; Bouchareychas, Laura; Kuchroo, Vijay K; Nestle, Frank O; Adamopoulos, Iannis E

    2016-12-01

    IL-17A has been strongly associated with epidermal hyperplasia in many cutaneous disorders. However, because IL-17A is mainly produced by αβ and γδT cells in response to IL-23, the role of T cells and IL-23 has overshadowed any IL-17A-independent actions. In this article, we report that IL-17A gene transfer induces epidermal hyperplasia in Il23r(-/-)Rag1(-/-)- and Tcrδ-deficient mice, which can be prevented by neutrophil depletion. Moreover, adoptive transfer of CD11b(+)Gr-1(hi) cells, after IL-17A gene transfer, was sufficient to phenocopy the disease. We further show that the IL-17A-induced pathology was prevented in transgenic mice with impaired neutrophil extracellular trap formation and/or neutrophils with conditional deletion of the master regulator of selective autophagy, Wdfy3. Our data demonstrate a novel T cell-independent mechanism that is associated with neutrophil extracellular trap formation and selective autophagy in IL-17A-mediated epidermal hyperplasia. Copyright © 2016 by The American Association of Immunologists, Inc.

  12. Pattern of distribution of blood group antigens on human epidermal cells during maturation

    DEFF Research Database (Denmark)

    Dabelsteen, Erik; Buschard, Karsten; Hakomori, Sen-Itiroh

    1984-01-01

    The distribution in human epidermis of A, B, and H blood group antigens and of a precursor carbohydrate chain, N-acetyl-lactosamine, was examined using immunofluorescence staining techniques. The material included tissue from 10 blood group A, 4 blood group B, and 9 blood group O persons. Murine...... on the lower spinous cells whereas H antigen was seen predominantly on upper spinous cells or on the granular cells. Epithelia from blood group A or B persons demonstrated A or B antigens, respectively, but only if the tissue sections were trypsinized before staining. In such cases A or B antigens were found...... monoclonal antibodies were used to identify H antigen (type 2 chain) and N-acetyl-lactosamine. Human antisera were used to identify A and B antigens. In all groups N-acetyl-lactosamine and H antigen were found on the cell membranes of the spinous cell layer. N-acetyl-lactosamine was present mainly...

  13. Templated green synthesis of plasmonic silver nanoparticles in onion epidermal cells suitable for surface-enhanced Raman and hyper-Raman scattering

    DEFF Research Database (Denmark)

    Palanco, Marta Espina; Mogensen, Klaus Bo; Guehlke, Marina

    2016-01-01

    We report fast and simple green synthesis of plasmonic silver nanoparticles in the epidermal cells of onions after incubation with AgNO3 solution. The biological environment supports the generation of silver nanostructures in two ways. The plant tissue delivers reducing chemicals for the initial...... formation of small silver clusters and their following conversion to plasmonic particles. Additionally, the natural morphological structures of the onion layers, in particular the extracellular matrix provides a biological template for the growth of plasmonic nanostructures. This is indicated by red glowing...... images of extracellular spaces in dark field microscopy of onion layers a few hours after AgNO3 exposure due to the formation of silver nanoparticles. Silver nanostructures generated in the extracellular space of onion layers and within the epidermal cell walls can serve as enhancing plasmonic structures...

  14. Epidermal Growth Factor Receptor targeting in non-small cell lung cancer: revisiting different strategies against the same target.

    Science.gov (United States)

    Castañón, Eduardo; Martín, Patricia; Rolfo, Christian; Fusco, Juan P; Ceniceros, Lucía; Legaspi, Jairo; Santisteban, Marta; Gil-Bazo, Ignacio

    2014-01-01

    Epidermal Growth Factor Receptor (EGFR) tyrosine kinase inhibitors (TKIs) have changed the paradigm of treatment in non-small cell lung cancer (NSCLC). The molecular biology study of EGFR has led to clinical trials that select patients more accurately, regarding the presence of EGFR activating mutations. Nonetheless, a lack of response or a temporary condition of the response has been detected in patients on EGFR TKIs. This has urged to study potential resistance mechanisms underneath. The most important ones are the presence of secondary mutations in EGFR, such as T790M, or the overexpression of mesenchymal-epithelial transition factor (MET) that may explain why patients who initially respond to EGFR TKIs, may ultimately become refractory. Several approaches have been taken and new drugs both targeting EGFR resistance-mutation or MET are currently being developed. Here we review and update the EGFR biological pathway as well as the clinical data leading to approval of the EGFR TKIs currently in the market. New compounds under investigation targeting resistance mutations or dually targeting EGFR and other relevant receptors are also reviewed and discussed.

  15. Attenuation fluctuations and local dermal reflectivity are indicators of immune cell infiltrate and epidermal hyperplasia in skin inflammation

    Science.gov (United States)

    Phillips, Kevin G.; Wang, Yun; Choudhury, Niloy; Levitz, David; Swanzey, Emily; Lagowski, James; Kulesz-Martin, Molly; Jacques, Steven

    2012-02-01

    Psoriasis is a common inflammatory skin disease resulting from genetic and environmental alterations of cutaneous immune responses responsible for skin homeostasis. While numerous therapeutic targets involved in the immunopathogenesis of psoriasis have been identified, the in vivo dynamics of psoriasis remains under investigated. To elucidate the spatial-temporal morphological evolution of psoriasis we undertook in vivo time course focus-tracked optical coherence tomography (OCT) imaging to non-invasively document dermal alterations due to immune cell infiltration and epidermal hyperplasia in an Imiquimod (IMQ) induced model of psoriasis-like inflammation in DBA2/C57Bl6 hybrid mice. Quantitative appraisal of dermal architectural changes was achieved through a three parameter fit of OCT axial scans in the dermis of the form A(z) = ρ exp(-mu;z +ɛ(z)). Ensemble averaging of the fit parameters over 2000 axial scans per mouse in each treatment arm revealed that the local dermal reflectivity ρ, decreased significantly in response to 6 day IMQ treatment (p = 0.0001), as did the standard deviation of the attenuation fluctuation std(ɛ(z)), (p = 0.04), in comparison to cream controls and day 1 treatments. No significant changes were observed in the average dermal attenuation rate, μ. Our results suggest these label-free OCT-based metrics can be deployed to investigate new therapeutic targets in animal models as well as aid in clinical staging of psoriasis in conjunction with the psoriasis area and severity index.

  16. Epidermal growth factor receptor inhibitors in non-small cell lung cancer: current status and future perspectives

    Directory of Open Access Journals (Sweden)

    Mauro Zükin

    2012-04-01

    Full Text Available Two classes of epidermal growth factor receptor (EGFR inhibitors are currently available for clinical use: tyrosine-kinase inhibitors (TKIs and monoclonal antibodies. The introduction of pharmacological agents that are able to inhibit EGFR represents an important step in the management of patients with advanced non-small cell lung cancer (NSCLC, the leading cause of cancer death worldwide. The use of EGFR inhibitors has not only led to meaningful therapeutic gains for patients, but has also expanded our knowledge about the disease itself, as it is now recognized that activating mutations of EGFR play a pathogenetic role in NSCLC, especially in adenocarcinoma, patients who never smoked or former light smokers, females, and Asian individuals. Patients with NSCLC and one or more of these features are more likely to harbor tumors with EGFR mutations, and hence to respond to TKIs, than individuals without these features. Currently, TKIs are considered by many as the treatment of first choice in both the first- and second-line treatment of patients with clinical or molecular predictors of therapeutic benefit, and chemotherapy is a second option in these cases, especially when activating mutations of EGFR are present. Moreover, TKIs and anti-EGFR antibodies may be used in other settings, and their therapeutic role in NSCLC is clearly expanding. However, despite an initially successful treatment course, patients with advanced NSCLC eventually develop resistance to TKIs; and novel agents that hold promise for the future include irreversible EGFR inhibitors with activity against resistance-conferring EGFR mutations.

  17. Deep mutational scanning of an antibody against epidermal growth factor receptor using mammalian cell display and massively parallel pyrosequencing.

    Science.gov (United States)

    Forsyth, Charles M; Juan, Veronica; Akamatsu, Yoshiko; DuBridge, Robert B; Doan, Minhtam; Ivanov, Alexander V; Ma, Zhiyuan; Polakoff, Dixie; Razo, Jennifer; Wilson, Keith; Powers, David B

    2013-01-01

    We developed a method for deep mutational scanning of antibody complementarity-determining regions (CDRs) that can determine in parallel the effect of every possible single amino acid CDR substitution on antigen binding. The method uses libraries of full length IgGs containing more than 1000 CDR point mutations displayed on mammalian cells, sorted by flow cytometry into subpopulations based on antigen affinity and analyzed by massively parallel pyrosequencing. Higher, lower and neutral affinity mutations are identified by their enrichment or depletion in the FACS subpopulations. We applied this method to a humanized version of the anti-epidermal growth factor receptor antibody cetuximab, generated a near comprehensive data set for 1060 point mutations that recapitulates previously determined structural and mutational data for these CDRs and identified 67 point mutations that increase affinity. The large-scale, comprehensive sequence-function data sets generated by this method should have broad utility for engineering properties such as antibody affinity and specificity and may advance theoretical understanding of antibody-antigen recognition.

  18. Isolation of a sesquiterpene synthase expressing in specialized epithelial cells surrounding the secretory cavities in rough lemon (Citrus jambhiri).

    Science.gov (United States)

    Uji, Yuya; Ozawa, Rika; Shishido, Hodaka; Taniguchi, Shiduku; Takabayashi, Junji; Akimitsu, Kazuya; Gomi, Kenji

    2015-05-15

    Volatile terpenoids such as monoterpenes and sesquiterpenes play multiple roles in plant responses and are synthesized by terpene synthases (TPSs). We have previously isolated a partial TPS gene, RlemTPS4, that responds to microbial attack in rough lemon. In this study, we isolated a full length RlemTPS4 cDNA from rough lemon. RlemTPS4 localized in the cytosol. The recombinant RlemTPS4 protein was obtained using a prokaryotic expression system and GC-MS analysis of the terpenes produced by the RlemTPS4 enzymatic reaction determined that RlemTPS4 produces some sesquiterpenes such as δ-elemene. The RlemTPS4 gene was specifically expressed in specialized epithelial cells surrounding the oil secretory cavities in rough lemon leaf tissue.

  19. Mn-doped Zinc Sulphide nanocrystals for immunofluorescent labeling of epidermal growth factor receptors on cells and clinical tumor tissues

    Science.gov (United States)

    J, Aswathy; V, Seethalekshmy N.; R, Hiran K.; R, Bindhu M.; K, Manzoor; Nair, Shantikumar V.; Menon, Deepthy

    2014-11-01

    The field of molecular detection and targeted imaging has evolved considerably with the introduction of fluorescent semiconductor nanocrystals. Manganese-doped zinc sulphide nanocrystals (ZnS:Mn NCs), which are widely used in electroluminescent displays, have been explored for the first time for direct immunofluorescent (IF) labeling of clinical tumor tissues. ZnS:Mn NCs developed through a facile wet chemistry route were capped using amino acid cysteine, conjugated to streptavidin and thereafter coupled to biotinylated epidermal growth factor receptor (EGFR) antibody utilizing the streptavidin-biotin linkage. The overall conjugation yielded stable EGFR antibody conjugated ZnS:Mn NCs (EGFR ZnS:Mn NCs) with a hydrodynamic diameter of 65 ± 15 nm, and having an intense orange-red fluorescence emission at 598 nm. Specific labeling of EGF receptors on EGFR+ve A431 cells in a co-culture with EGFR-ve NIH3T3 cells was demonstrated using these nanoprobes. The primary antibody conjugated fluorescent NCs could also clearly delineate EGFR over-expressing cells on clinical tumor tissues processed by formalin fixation as well as cryopreservation with a specificity of 86% and accuracy of 88%, in comparison to immunohistochemistry. Tumor tissues labeled with EGFR ZnS:Mn NCs showed good fluorescence emission when imaged after storage even at 15 months. Thus, ZnS nanobioconjugates with dopant-dependent and stable fluorescence emission show promise as an efficient, target-specific fluorophore that would enable long term IF labeling of any antigen of interest on clinical tissues.

  20. PKM2 inhibitor shikonin suppresses TPA-induced mitochondrial malfunction and proliferation of skin epidermal JB6 cells.

    Science.gov (United States)

    Li, Wenjuan; Liu, Joan; Zhao, Yunfeng

    2014-05-01

    Chemoprevention has been a pivotal and effective strategy during the skin cancer treatment. Using human skin normal and tumor samples, we demonstrated that both the expression and activity levels of pyruvate kinase M2 (PKM2) were higher in skin tumor tissues than normal tissues, suggesting that PKM2, one of important metabolic enzyme, might serve as a target for skin cancer prevention and/or therapy. Shikonin, a small-molecule active chemical, has been studied as an anti-cancer drug candidate in human cancer models. However, the mechanism of action and the chemopreventive potential of shikonin are unclear. Herein, we used the skin epidermal JB6 P+ cells and demonstrated that shikonin suppressed the tumor promoter 12-O-tetradecanoylphorbol 13-acetate (TPA) induced neoplastic cell transformation and PKM2 activation in the early stage of carcinogenesis. Mitochondrial functions were inhibited by TPA treatment, as indicated by reduced mitochondrial membrane potential and mitochondrial respiration, which were restored by shikonin. We also examined the levels of lactate as a glycolysis marker, and shikonin suppressed its increase caused by tumor promoter treatment. Modulation of cell metabolism by shikonin was associated with G2-M phase accumulation, and Fra-1 (a major subunit of activator protein 1 in skin tumorigenesis) downregulation. In addition, we demonstrated that AMP-activated protein kinase (AMPK), an energy sensor, which is inactivated by TPA, shikonin could reverse AMPK activity. These results suggest that shikonin bears chemopreventive potential for human skin cancers in which PKM2 is upregulated, which might be mediated by inhibiting oncogenic activation, PKM2 activation, and mitochondrial dysfunction.

  1. Human epidermal keratinocyte cell response on integrin-specific artificial extracellular matrix proteins.

    Science.gov (United States)

    Tjin, Monica Suryana; Chua, Alvin Wen Choong; Ma, Dong Rui; Lee, Seng Teik; Fong, Eileen

    2014-08-01

    Cell-matrix interactions play critical roles in regulating cellular behavior in wound repair and regeneration of the human skin. In particular, human skin keratinocytes express several key integrins such as alpha5beta1, alpha3beta1, and alpha2beta1 for binding to the extracellular matrix (ECM) present in the basement membrane in uninjured skin. To mimic these key integrin-ECM interactions, artificial ECM (aECM) proteins containing functional domains derived from laminin 5, type IV collagen, fibronectin, and elastin are prepared. Human skin keratinocyte cell responses on the aECM proteins are specific to the cell-binding domain present in each construct. Keratinocyte attachment to the aECM protein substrates is also mediated by specific integrin-material interactions. In addition, the aECM proteins are able to support the proliferation of keratinocyte stem cells, demonstrating their promise for use in skin tissue engineering.

  2. Studies on Bluing Effect in the Petals of Red Rose VII. : Cytological Observation on the Epidermal Cells of Bluing Petals Incorporated into the Miscellaneous-type.

    OpenAIRE

    YASUDA, Hitoshi; YONEDA, AKIO

    1985-01-01

    The miscellaneous-type of bluing in rose petals (YASUDA and KIKUCHI, 1978) was re-examined using the following five cultivars: Cardinal de Richelieu, Blue Boy, Reine des Violettes, Shigyoku, and Samurai. The massive structures appearing in the epidermal cells of their petals showed striking similarity to the anthocyanophore-like structure in some rose petals which was reported by YASUDA in 1974b, 1976 and 1979 at three points: 1) staining features both with ruthenium red and safranine, 2) dev...

  3. Pleiotropic phenotypes of the sticky peel mutant provide new insight into the role of CUTIN DEFICIENT2 in epidermal cell function in tomato.

    Science.gov (United States)

    Nadakuduti, Satya Swathi; Pollard, Mike; Kosma, Dylan K; Allen, Charles; Ohlrogge, John B; Barry, Cornelius S

    2012-07-01

    Plant epidermal cells have evolved specialist functions associated with adaptation to stress. These include the synthesis and deposition of specialized metabolites such as waxes and cutin together with flavonoids and anthocyanins, which have important roles in providing a barrier to water loss and protection against UV radiation, respectively. Characterization of the sticky peel (pe) mutant of tomato (Solanum lycopersicum) revealed several phenotypes indicative of a defect in epidermal cell function, including reduced anthocyanin accumulation, a lower density of glandular trichomes, and an associated reduction in trichome-derived terpenes. In addition, pe mutant fruit are glossy and peels have increased elasticity due to a severe reduction in cutin biosynthesis and altered wax deposition. Leaves of the pe mutant are also cutin deficient and the epicuticular waxes contain a lower proportion of long-chain alkanes. Direct measurements of transpiration, together with chlorophyll-leaching assays, indicate increased cuticular permeability of pe leaves. Genetic mapping revealed that the pe locus represents a new allele of CUTIN DEFICIENT2 (CD2), a member of the class IV homeodomain-leucine zipper gene family, previously only associated with cutin deficiency in tomato fruit. CD2 is preferentially expressed in epidermal cells of tomato stems and is a homolog of Arabidopsis (Arabidopsis thaliana) ANTHOCYANINLESS2 (ANL2). Analysis of cuticle composition in leaves of anl2 revealed that cutin accumulates to approximately 60% of the levels observed in wild-type Arabidopsis. Together, these data provide new insight into the role of CD2 and ANL2 in regulating diverse metabolic pathways and in particular, those associated with epidermal cells.

  4. Fermented milk containing Lactobacillus GG alleviated DSS-induced colitis in mice and activated epidermal growth factor receptor and Akt signaling in intestinal epithelial cells

    Directory of Open Access Journals (Sweden)

    Kazutoyo Yoda

    2012-06-01

    Full Text Available Lactobacillus rhamnosus GG was assessed for its ability to alleviate DSS-induced colitis in mice and activate epidermal growth factor receptor and Akt signaling in intestinal epithelial cells. In this study mice were treated with DSS to induce colitis and they were given Lactobacillus GG fermented milk to assess the effect of probiotic on colitis. Lactobacillus GG fermented milk significantly reduced the colitis associated changes suggesting a protective effect against DSS induced colitis.

  5. Identification of Candidate Transcriptional Regulators of Epidermal Transfer Cell Development in Vicia faba Cotyledons

    OpenAIRE

    Arun-Chinnappa, Kiruba S.; McCurdy, David W.

    2016-01-01

    Transfer cells (TCs) are anatomically-specialized cells formed at apoplasmic-symplasmic bottlenecks in nutrient transport pathways in plants. TCs form invaginated wall ingrowths which provide a scaffold to amplify plasma membrane surface area and thus increase the density of nutrient transporters required to achieve enhanced nutrient flow across these bottlenecks. Despite their importance to nutrient transport in plants, little is known of the transcriptional regulation of wall ingrowth forma...

  6. Theca cells and theca-cell conditioned medium inhibit the progression of FSH-induced meiosis of bovine oocytes surrounded by cumulus cells connected to membrana granulosa.

    Science.gov (United States)

    van Tol, H T; Bevers, M M

    1998-11-01

    The effect of follicular cells and their conditioned media on the FSH-induced oocyte maturation of oocytes surrounded by cumulus cells connected to the membrana granulosa (COCGs) was investigated. COCGs and cumulus oocyte complexes (COCs) were cultured for 22 hr in M199 supplemented with 0.05 IU FSH/ml in either the presence of pieces of theca cell layer or in the presence of pieces of membrana granulosa. COCGs and COCs were also cultured for 22 hr in either theca-cell conditioned medium (CMt) or in granulosa cell conditioned medium (CMg), both supplemented with 0.05 IU FSH/ml. To investigate the importance of cell-cell contacts between granulosa cells and cumulus cells, oocytes were cultured as COCs in CMt, as COCs in CMt supplemented with pieces of membrana granulosa, or as COCGs in CMt. In all groups the medium was supplemented with 0.05 IU FSH/ml. After culture the nuclear status of the oocytes was assessed using orcein staining. Culture of COCGs in the presence of theca cells as well as in CMt resulted in a significantly decreased proportion of oocytes that had undergone germinal vesicle breakdown (GVBD) at the end of the culture period as compared to the control. Of the oocytes that resumed meiosis in the presence of theca cells or in CMt, the proportion of oocytes that progressed up to the MII stage was significantly reduced. This indicates the production of a meiosis-inhibiting factor by theca cells. Culture with COCs instead of COCGs resulted in comparable results although the effect was less pronounced. The significant effect on the progression of meiosis of oocytes cultured as COCGs or as COCs, obtained in the presence of granulosa cells or in CMg, was much weaker than the effect of theca cells or culture in CMt. Culture of COCs in CMt supplemented with layers of membrana granulosa and 0.05 IU FSH/ml, resulted in significantly less oocytes that resumed meiosis as compared to culture of COCs in CMt. Of the oocytes that showed GVBD, the proportion that

  7. Blockade of Hedgehog Signaling Synergistically Increases Sensitivity to Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors in Non-Small-Cell Lung Cancer Cell Lines.

    Directory of Open Access Journals (Sweden)

    Xiao-Yan Bai

    Full Text Available Aberrant activation of the hedgehog (Hh signaling pathway has been implicated in the epithelial-to-mesenchymal transition (EMT and cancer stem-like cell (CSC maintenance; both processes can result in tumor progression and treatment resistance in several types of human cancer. Hh cooperates with the epidermal growth factor receptor (EGFR signaling pathway in embryogenesis. We found that the Hh signaling pathway was silenced in EGFR-TKI-sensitive non-small-cell lung cancer (NSCLC cells, while it was inappropriately activated in EGFR-TKI-resistant NSCLC cells, accompanied by EMT induction and ABCG2 overexpression. Upregulation of Hh signaling through extrinsic SHH exposure downregulated E-cadherin expression and elevated Snail and ABCG2 expression, resulting in gefitinib tolerance (P < 0.001 in EGFR-TKI-sensitive cells. Blockade of the Hh signaling pathway using the SMO antagonist SANT-1 restored E-cadherin expression and downregulate Snail and ABCG2 in EGFR-TKI-resistant cells. A combination of SANT-1 and gefitinib markedly inhibited tumorigenesis and proliferation in EGFR-TKI-resistant cells (P < 0.001. These findings indicate that hyperactivity of Hh signaling resulted in EGFR-TKI resistance, by EMT introduction and ABCG2 upregulation, and blockade of Hh signaling synergistically increased sensitivity to EGFR-TKIs in primary and secondary resistant NSCLC cells. E-cadherin expression may be a potential biomarker of the suitability of the combined application of an Hh inhibitor and EGFR-TKIs in EGFR-TKI-resistant NSCLCs.

  8. Matriptase promotes inflammatory cell accumulation and progression of established epidermal tumors

    DEFF Research Database (Denmark)

    Sales, K U; Friis, S; Abusleme, L

    2015-01-01

    Deregulation of matriptase is a consistent feature of human epithelial cancers and correlates with poor disease outcome. We have previously shown that matriptase promotes multi-stage squamous cell carcinogenesis in transgenic mice through dual activation of pro-hepatocyte growth factor-cMet-Akt-m......Deregulation of matriptase is a consistent feature of human epithelial cancers and correlates with poor disease outcome. We have previously shown that matriptase promotes multi-stage squamous cell carcinogenesis in transgenic mice through dual activation of pro-hepatocyte growth factor...

  9. Bile acids induce hepatic stellate cell proliferation via activation of the epidermal growth factor receptor

    NARCIS (Netherlands)

    Svegliati-Baroni, G; Ridolfi, F; Hannivoort, R; Saccomanno, S; Homan, M; De Minicis, S; Jansen, PLM; Candelaresi, C; Benedetti, A; Moshage, H

    2005-01-01

    Background B Aims: Hepatic stellate cell (HSC) proliferation is a key event in the development of liver fibrosis. In many liver diseases, HSCs are exposed to inflammatory cytokines, reactive oxygen species, and bile acids. Although inflammatory cytokines and reactive oxygen species are known to prom

  10. Hypertrophic scar formation is associated with an increased number of epidermal Langerhans cells

    NARCIS (Netherlands)

    Niessen, FB; Schalkwijk, J; Vos, H; Timens, W

    The exact pathogenesis of hypertrophic scar and keloid formation is still unknown and a good therapy to prevent or treat these scars is lacking. Because immunological processes seem to be important in excessive scar formation, immunological cells and parameters were studied in a standardized breast

  11. Dissection of Arabidopsis ADP-Ribosylation Factor 1 function in epidermal cell polarity

    NARCIS (Netherlands)

    Xu, J.; Scheres, B.J.G.

    2005-01-01

    Vesicle trafficking is essential for the generation of asymmetries, which are central to multicellular development. Core components of the vesicle transport machinery, such as ADP-ribosylation factor (ARF) GTPases, have been studied primarily at the single-cell level. Here, we analyze developmental

  12. Dissection of Arabidopsis ADP-Ribosylation Factor 1 function in epidermal cell polarity

    NARCIS (Netherlands)

    Xu, J.; Scheres, B.J.G.

    2005-01-01

    Vesicle trafficking is essential for the generation of asymmetries, which are central to multicellular development. Core components of the vesicle transport machinery, such as ADP-ribosylation factor (ARF) GTPases, have been studied primarily at the single-cell level. Here, we analyze developmental

  13. Distribution and number of epidermal growth factor receptors in skin is related to epithelial cell growth

    DEFF Research Database (Denmark)

    Green, M R; Basketter, D A; Couchman, J R

    1983-01-01

    receptors are detected on the epithelial cells overlying the basement membranes of the epidermis, sebaceous gland, and regions of the hair follicle all of which have proliferative capacity. In marked contrast, tissues which have started to differentiate and lost their growth potential, carry either...... and temporal control of epithelial proliferation....

  14. Epidermal Growth Factor Receptor and K-RAS status in two cohorts of squamous cell carcinomas

    Directory of Open Access Journals (Sweden)

    Van Laethem Jean-Luc

    2010-05-01

    Full Text Available Abstract Background With the availability of effective anti-EGFR therapies for various solid malignancies, such as non-cell small lung cancer, colorectal cancer and squamous cell carcinoma of the head and neck, the knowledge of EGFR and K-RAS status becomes clinically important. The aim of this study was to analyse EGFR expression, EGFR gene copy number and EGFR and K-RAS mutations in two cohorts of squamous cell carcinomas, specifically anal canal and tonsil carcinomas. Methods Formalin fixed, paraffin-embedded tissues from anal and tonsil carcinoma were used. EGFR protein expression and EGFR gene copy number were analysed by means of immunohistochemistry and fluorescence in situ hybridisation. The somatic status of the EGFR gene was investigated by PCR using primers specific for exons 18 through 21. For the K-RAS gene, PCR was performed using exon 2 specific primers. Results EGFR immunoreactivity was present in 36/43 (83.7% of anal canal and in 20/24 (83.3% of tonsil squamous cell carcinomas. EGFR amplification was absent in anal canal tumours (0/23, but could be identified in 4 of 24 tonsil tumours. From 38 anal canal specimens, 26 specimens were successfully analysed for exon 18, 30 for exon 19, 34 for exon 20 and 30 for exon 21. No EGFR mutations were found in the investigated samples. Thirty samples were sequenced for K-RAS exon 2 and no mutation was identified. From 24 tonsil specimens, 22 were successfully analysed for exon 18 and all 24 specimens for exon 19, 20 and 21. No EGFR mutations were found. Twenty-two samples were sequenced for K-RAS exon 2 and one mutation c.53C > A was identified. Conclusion EGFR mutations were absent from squamous cell carcinoma of the anus and tonsils, but EGFR protein expression was detected in the majority of the cases. EGFR amplification was seen in tonsil but not in anal canal carcinomas. In our investigated panel, only one mutation in the K-RAS gene of a tonsil squamous cell carcinoma was identified

  15. Blockade of Ets-1 attenuates epidermal growth factor-dependent collagen loss in human carotid plaque smooth muscle cells.

    Science.gov (United States)

    Rao, Velidi H; Rai, Vikrant; Stoupa, Samantha; Agrawal, Devendra K

    2015-09-15

    Although degradation of extracellular matrix by matrix metalloproteinases (MMPs) is thought to be involved in symptomatic (S) carotid plaques in atherosclerosis, the mechanisms of MMP expression are poorly understood. Here, we demonstrate that collagen loss in vascular smooth vessel cells (VSMCs) isolated from S plaques was induced by epidermal growth factor (EGF) through the activation of p38-MAPK and JNK-MAPK pathways. Inhibitors of p38-MAPK and JNK-MAPK signaling pathways downregulated the expression of MMP-1 and MMP-9. In addition, we examined whether v-ets erythroblastosis virus E26 oncogene homologue 1 (Ets-1), an important regulator of different genes, is involved in destabilizing S plaques in patients with carotid stenosis. We demonstrate that EGF induces Ets-1 expression and decreases interstitial and basement membrane collagen in vascular smooth muscle cells (VSMCs) from patients with carotid stenosis. Increased expression of MMP-1 and -9 and decreased collagen mRNA transcripts were also found in Ets-1-overexpressed VSMCs. Transfection with both dominant-negative form of Ets-1 and small interfering RNA blocked EGF-induced MMP-1 and -9 expressions and increased the mRNA transcripts for collagen I (α1) and collagen III (α1) in S compared with asymptomatic (AS) carotid plaques. Inhibitors of p38-MAPK (SB202190) and JNK-MAPK (SP600125) signaling pathways decreased the expression of Ets-1, MMP-1, and MMP-9 and increased collagen type I and III expression in EGF-treated VSMCs. This study provides a mechanistic insight into the role of Ets-1 in the plaque destabilization in patients with carotid stenosis involving p38-MAPK and JNK signaling pathways. Copyright © 2015 the American Physiological Society.

  16. CCR6 is required for epidermal trafficking of γδ T cells in an IL-23-induced model of psoriasiform dermatitis

    Science.gov (United States)

    Mabuchi, Tomotaka; Singh, Tej Pratap; Takekoshi, Tomonori; Jia, Guang-fu; Wu, Xuesong; Kao, Mandy C.; Weiss, Ido; Farber, Joshua M.; Hwang, Sam T.

    2012-01-01

    A subset of CCR6+, γδ-low (GDL) T cells that express Th17 cytokines in mouse skin participates in IL-23-induced psoriasisform dermatitis. We use CCR6-deficient (KO) and wildtype (WT) mice to analyze skin trafficking patterns of GDL T cells and function-blocking mAbs to determine the role of CCR6 in IL-23-mediated dermatitis. Herein, CCL20 was highly upregulated in IL-23-injected WT mouse ear skin as early as 24 hours after initial treatment, and large numbers of CCR6+ cells were observed in the epidermis of IL-23-injected WT mice. Anti-CCL20 mAbs reduced psoriasiform dermatitis and blocked recruitment of GDL T cells to the epidermis. In CCR6 KO mice, GDL T cells failed to accumulate in the epidermis after IL-23 treatment, but total numbers of GDL T cells in the dermis of WT and CCR6 KO mice were equivalent. There was a ~70% reduction in the proportion of IL-22+ GDL T cells in the dermis of CCR6 KO mice (vs. WT mice), suggesting that effector function as well as epidermal recruitment of GDL T cells are impaired in CCR6-deficient mice. Thus, these data show CCR6 regulates epidermal trafficking of γδ T cell subsets in skin and suggest the potential of CCR6 as a therapeutic target for psoriasis. PMID:22895364

  17. Inhibition of the epidermal growth factor receptor in bladder cancer cells treated with the DNA-damaging drug etoposide markedly increases apoptosis

    DEFF Research Database (Denmark)

    Munk, Mathias; Memon, Ashfaque Ahmed; Nexo, Ebba

    2007-01-01

    OBJECTIVE: To investigate the effect of the epidermal growth factor receptor (EGFR) on the induction of apoptosis by the chemotherapeutic agent etoposide (VP16), and to examine the effect of combining VP16 with gefitinib to see if the cell-survival mechanism can be prevented. MATERIALS AND METHOD...... suggest that activation of the EGFR induced a cell-survival function when bladder cancer cells were treated with the DNA-damaging drug VP16, and that combined treatment with VP16 and the EGFR inhibitor gefitinib might improve the efficacy of treatment. Udgivelsesdato: 2007-Jan...

  18. Neural cell adhesion molecule-180-mediated homophilic binding induces epidermal growth factor receptor (EGFR) down-regulation and uncouples the inhibitory function of EGFR in neurite outgrowth

    DEFF Research Database (Denmark)

    Povlsen, Gro Klitgaard; Berezin, Vladimir; Bock, Elisabeth

    2008-01-01

    The neural cell adhesion molecule (NCAM) plays important roles in neuronal development, regeneration, and synaptic plasticity. NCAM homophilic binding mediates cell adhesion and induces intracellular signals, in which the fibroblast growth factor receptor plays a prominent role. Recent studies...... not require NCAM-mediated fibroblast growth factor receptor activation....... on axon guidance in Drosophila suggest that NCAM also regulates the epidermal growth factor receptor (EGFR) (Molecular and Cellular Neuroscience, 28, 2005, 141). A possible interaction between NCAM and EGFR in mammalian cells has not been investigated. The present study demonstrates for the first time...

  19. Assessment of cytotoxicity exerted by leaf extracts from plants of the genus Rhododendron towards epidermal keratinocytes and intestine epithelial cells.

    Science.gov (United States)

    Rezk, Ahmed; Al-Hashimi, Alaa; John, Warren; Schepker, Hartwig; Ullrich, Matthias S; Brix, Klaudia

    2015-10-15

    Rhododendron leaf extracts were previously found to exert antimicrobial activities against a range of Gram-positive bacteria. In this study, we investigated which of the extracts with these antimicrobial properties would be best suited for further exploitation. Specifically, the project aims to identify biologically active compounds that affect bacterial but not mammalian cells when applied in medical treatments such as lotions for ectopic application onto skin, or as orally administered drugs. Different concentrations of DMSO-dissolved remnants of crude methanol Rhododendron leaf extracts were incubated for 24 h with cultured epidermal keratinocytes (human HaCaT cell line) and epithelial cells of the intestinal mucosa (rat IEC6 cell line) and tested for their cytotoxic potential. In particular, the cytotoxic potencies of the compounds contained in antimicrobial Rhododendron leaf extracts were assessed by quantifying their effects on (i) plasma membrane integrity, (ii) cell viability and proliferation rates, (iii) cellular metabolism, (iv) cytoskeletal architecture, and (v) determining initiation of cell death pathways by morphological and biochemical means. Extracts of almost all Rhododendron species, when applied at 500 μg/mL, were potent in negatively affecting both keratinocytes and intestine epithelial cells, except material from R. hippophaeoides var. hippophaeoides. Extracts of R. minus and R. racemosum were non-toxic towards both mammalian cell types when used at 50 μg/mL, which was equivalent to their minimal inhibitory concentration against bacteria. At this concentration, leaf extracts from three other highly potent antimicrobial Rhododendron species proved non-cytotoxic against one or the other mammalian cell type: Extracts of R. ferrugineum were non-toxic towards IEC6 cells, and extracts of R. rubiginosum as well as R. concinnum did not affect HaCaT cells. In general, keratinocytes proved more resistant than intestine epithelial cells against the

  20. Malignant T cells secrete galectins and induce epidermal hyperproliferation and disorganized stratification in a skin model of cutaneous T-cell lymphoma.

    Science.gov (United States)

    Thode, Christenze; Woetmann, Anders; Wandall, Hans H; Carlsson, Michael C; Qvortrup, Klaus; Kauczok, Claudia S; Wobser, Marion; Printzlau, Andreas; Ødum, Niels; Dabelsteen, Sally

    2015-01-01

    Cutaneous T-cell lymphomas (CTCLs) are the most common primary skin lymphomas, which are characterized by an accumulation of malignant T cells in the skin. The early lesion resembles both clinically and histologically benign inflammatory disorders and also presents with hyperproliferative epidermis and T-cell infiltration. Despite considerable progress in understanding the molecular mechanisms involved in the malignant transformation of T cells, the causes of the morphological and histopathological features of the disease are largely unknown. We used an organotypic model of CTCL to show that malignant T cells through the secretion of galectin-1 and -3 stimulate vigorous growth of keratinocytes. In parallel, malignant T cells induce disorganized keratinocyte stratification, resembling the early hyperproliferative stage of CTCL. We also observed a loss of attachment between the epithelial and mesenchymal compartments. In addition, hyperproliferation was followed by a downregulation of differentiation markers, such as keratin 10 and involucrin, and a decrease in barrier formation. In conclusion, we provide evidence that malignant T cells orchestrate the histopathological epidermal changes seen in CTCL.

  1. Combined effects of lapatinib and bortezomib in human epidermal receptor 2 (HER2)-overexpressing breast cancer cells and activity of bortezomib against lapatinib-resistant breast cancer cells.

    Science.gov (United States)

    Ma, Chuandong; Niu, Xiuqing; Luo, Jianmin; Shao, Zhimin; Shen, Kunwei

    2010-10-01

    Lapatinib and bortezomib are highly active against breast cancer cells. Breast cancer patients who initially respond to lapatinib may eventually manifest acquired resistance to this treatment. Thus, the identification of novel agents that may prevent or delay the development of acquired resistance to lapatinib is critical. In the current study, we show that the combination of lapatinib and bortezomib results in a synergistic growth inhibition in human epidermal receptor 2 (HER2)-overexpressing breast cancer cells and that the combination enhances apoptosis of SK-BR-3 cells. Importantly, we found that the combination of lapatinib plus bortezomib more effectively blocked activation of the HER2 pathway in SK-BR-3 cells, compared with monotherapy. In addition, we established a model of acquired resistance to lapatinib by chronically challenging SK-BR-3 breast cancer cells with increasing concentrations of lapatinib. Here, we showed that bortezomib notably induced apoptosis of lapatinib-resistant SK-BR-3 pools and further inhibited HER2 signaling in the resistant cells. Taken together, the current data indicate a synergistic interaction between lapatinib and bortezomib in HER2-overexpressing breast cancer cells and provide the rationale for the clinical evaluation of these two noncross-resistant targeted therapies. The combination of lapatinib and bortezomib may be a potentially novel approach to prevent or delay the onset of acquired resistance to lapatinib in HER2-overxpressing/estrogen receptor (ER)-negative breast cancers.

  2. Temozolomide induces the production of epidermal growth factor to regulate MDR1 expression in glioblastoma cells.

    Science.gov (United States)

    Munoz, Jessian L; Rodriguez-Cruz, Vivian; Greco, Steven J; Nagula, Vipul; Scotto, Kathleen W; Rameshwar, Pranela

    2014-10-01

    Glioblastoma multiforme (GBM) commonly resists the frontline chemotherapy treatment temozolomide. The multidrug resistance gene (MDR1) and its protein, P-glycoprotein (P-gp), are associated with chemoresistance. This study investigated the mechanisms underlying MDR1-mediated resistance by GBM to temozolomide. P-gp trafficking was studied by flow cytometry and Western blot analysis. MDR1 expression was analyzed by real-time PCR and reporter gene assays. AP-1 interaction with MDR1 was studied by chromatin immunoprecipitation assay. EGF production was analyzed by ELISA, EGFR signaling was determined by Western blot analysis, and in vivo response to erlotinib and/or temozolomide was studied in nude mice. During the early phase of temozolomide treatment, intracellular P-gp was trafficked to the cell membrane, followed by conformational change into active P-gp. At the later phase, gene transcription of MDR1 was induced by temozolomide-mediated production of EGF. EGF activated ERK1/2-JNK-AP-1 cofactors (c-jun and c-fos). An inhibitor of EGFR kinase (erlotinib) given to nude mice with GBM prevented temozolomide-induced resistance. The results identified an essential role for activated EGFR in the resistance of GBM to temozolomide. Temozolomide resistance occurred through a biphasic response; first, by a conformational change in P-gp into the active form and, second, by releasing EGF, which caused autocrine stimulation of GBM cells to induce MDR1. Pharmacologic inhibition of EGFR kinase blunted the ability of GBM cells to resist temozolomide. These findings may explain reports on the common occurrence of mutant EGFR (EGFRvIII) and EGFR expansion in the resistance of GBM cells.

  3. In vivo UVB irradiation induces clustering of Fas (CD95) on human epidermal cells

    DEFF Research Database (Denmark)

    Bang, Bo; Gniadecki, Robert; Larsen, Jørgen K

    2003-01-01

    In vitro studies with human cell lines have demonstrated that the death receptor Fas plays a role in ultraviolet (UV)-induced apoptosis. The purpose of the present study was to investigate the relation between Fas expression and apoptosis as well as clustering of Fas in human epidermis after...... clustering has a functional significance. Our results ar in accordance with previous findings from in vitro studies, and suggest that Fas is activated in vivo in human epidermis after UVB exposure....

  4. Lipopolysaccharide (LPS-Induced Biliary Epithelial Cell NRas Activation Requires Epidermal Growth Factor Receptor (EGFR.

    Directory of Open Access Journals (Sweden)

    Christy E Trussoni

    Full Text Available Cholangiocytes (biliary epithelial cells actively participate in microbe-induced proinflammatory responses in the liver and contribute to inflammatory and infectious cholangiopathies. We previously demonstrated that cholangiocyte TLR-dependent NRas activation contributes to proinflammatory/ proliferative responses. We test the hypothesis that LPS-induced activation of NRas requires the EGFR. SV40-transformed human cholangiocytes (H69 cells, or low passage normal human cholangiocytes (NHC, were treated with LPS in the presence or absence of EGFR or ADAM metallopeptidase domain 17 (TACE inhibitors. Ras activation assays, quantitative RT-PCR, and proliferation assays were performed in cells cultured with or without inhibitors or an siRNA to Grb2. Immunofluorescence for phospho-EGFR was performed on LPS-treated mouse samples and specimens from patients with primary sclerosing cholangitis, primary biliary cirrhosis, hepatitis C, and normal livers. LPS-treatment induced an association between the TLR/MyD88 and EGFR/Grb2 signaling apparatus, NRas activation, and EGFR phosphorylation. NRas activation was sensitive to EGFR and TACE inhibitors and correlated with EGFR phosphorylation. The TACE inhibitor and Grb2 depletion prevented LPS-induced IL6 expression (p<0.05 and proliferation (p<0.01. Additionally, cholangiocytes from LPS-treated mouse livers and human primary sclerosing cholangitis (PSC livers exhibited increased phospho-EGFR (p<0.01. Moreover, LPS-induced mouse cholangiocyte proliferation was inhibited by concurrent treatment with the EGFR inhibitor, Erlotinib. Our results suggest that EGFR is essential for LPS-induced, TLR4/MyD88-mediated NRas activation and induction of a robust proinflammatory cholangiocyte response. These findings have implications not only for revealing the signaling potential of TLRs, but also implicate EGFR as an integral component of cholangiocyte TLR-induced proinflammatory processes.

  5. Lipopolysaccharide (LPS)-Induced Biliary Epithelial Cell NRas Activation Requires Epidermal Growth Factor Receptor (EGFR).

    Science.gov (United States)

    Trussoni, Christy E; Tabibian, James H; Splinter, Patrick L; O'Hara, Steven P

    2015-01-01

    Cholangiocytes (biliary epithelial cells) actively participate in microbe-induced proinflammatory responses in the liver and contribute to inflammatory and infectious cholangiopathies. We previously demonstrated that cholangiocyte TLR-dependent NRas activation contributes to proinflammatory/ proliferative responses. We test the hypothesis that LPS-induced activation of NRas requires the EGFR. SV40-transformed human cholangiocytes (H69 cells), or low passage normal human cholangiocytes (NHC), were treated with LPS in the presence or absence of EGFR or ADAM metallopeptidase domain 17 (TACE) inhibitors. Ras activation assays, quantitative RT-PCR, and proliferation assays were performed in cells cultured with or without inhibitors or an siRNA to Grb2. Immunofluorescence for phospho-EGFR was performed on LPS-treated mouse samples and specimens from patients with primary sclerosing cholangitis, primary biliary cirrhosis, hepatitis C, and normal livers. LPS-treatment induced an association between the TLR/MyD88 and EGFR/Grb2 signaling apparatus, NRas activation, and EGFR phosphorylation. NRas activation was sensitive to EGFR and TACE inhibitors and correlated with EGFR phosphorylation. The TACE inhibitor and Grb2 depletion prevented LPS-induced IL6 expression (pphospho-EGFR (p<0.01). Moreover, LPS-induced mouse cholangiocyte proliferation was inhibited by concurrent treatment with the EGFR inhibitor, Erlotinib. Our results suggest that EGFR is essential for LPS-induced, TLR4/MyD88-mediated NRas activation and induction of a robust proinflammatory cholangiocyte response. These findings have implications not only for revealing the signaling potential of TLRs, but also implicate EGFR as an integral component of cholangiocyte TLR-induced proinflammatory processes.

  6. Selective Killing Effects of Cold Atmospheric Pressure Plasma with NO Induced Dysfunction of Epidermal Growth Factor Receptor in Oral Squamous Cell Carcinoma.

    Directory of Open Access Journals (Sweden)

    Jung-Hwan Lee

    Full Text Available The aim of this study is to investigate the effects of cold atmospheric pressure plasma (CAP-induced radicals on the epidermal growth factor receptor (EGFR, which is overexpressed by oral squamous cell carcinoma, to determine the underlying mechanism of selective killing. CAP-induced highly reactive radicals were observed in both plasma plume and cell culture media. The selective killing effect was observed in oral squamous cell carcinoma compared with normal human gingival fibroblast. Degradation and dysfunction of EGFRs were observed only in the EGFR-overexpressing oral squamous cell carcinoma and not in the normal cell. Nitric oxide scavenger pretreatment in cell culture media before CAP treatment rescued above degradation and dysfunction of the EGFR as well as the killing effect in oral squamous cell carcinoma. CAP may be a promising cancer treatment method by inducing EGFR dysfunction in EGFR-overexpressing oral squamous cell carcinoma via nitric oxide radicals.

  7. Selective Killing Effects of Cold Atmospheric Pressure Plasma with NO Induced Dysfunction of Epidermal Growth Factor Receptor in Oral Squamous Cell Carcinoma.

    Science.gov (United States)

    Lee, Jung-Hwan; Om, Ji-Yeon; Kim, Yong-Hee; Kim, Kwang-Mahn; Choi, Eun-Ha; Kim, Kyoung-Nam

    2016-01-01

    The aim of this study is to investigate the effects of cold atmospheric pressure plasma (CAP)-induced radicals on the epidermal growth factor receptor (EGFR), which is overexpressed by oral squamous cell carcinoma, to determine the underlying mechanism of selective killing. CAP-induced highly reactive radicals were observed in both plasma plume and cell culture media. The selective killing effect was observed in oral squamous cell carcinoma compared with normal human gingival fibroblast. Degradation and dysfunction of EGFRs were observed only in the EGFR-overexpressing oral squamous cell carcinoma and not in the normal cell. Nitric oxide scavenger pretreatment in cell culture media before CAP treatment rescued above degradation and dysfunction of the EGFR as well as the killing effect in oral squamous cell carcinoma. CAP may be a promising cancer treatment method by inducing EGFR dysfunction in EGFR-overexpressing oral squamous cell carcinoma via nitric oxide radicals.

  8. [Effects of lentivirus-mediated epidermal growth factor-like domain 7 silencing on proliferation and invasion of human laryngeal carcinoma Hep-2 cells].

    Science.gov (United States)

    Li, Jingjia; Ye, Jin; Zhuang, Shimin; Wang, Tao; Wang, Zhiyuan; Chang, Lihong; Zhang, Gehua

    2014-08-01

    To explore the effects of epidermal growth factor-like domain 7 (EGFL7) gene silencing on the proliferation and invasion ablity of laryngeal carcinoma cells. A lentiviral vector expressing EGFL7 shRNA was constructed and transfected into human laryngeal carcinoma Hep-2 cells. The expressions of EGFL7 mRNA and protein were detected by Real-time PCR and Western blot, respectively. Cell proliferation was evaluated by CCK-8 assay, cell cycle and apoptosis were tested by flow cytometry, and cell invasion was detected by transwell invasion assay. The relative expression level s of EGFL7 mRNA and protein in EGFL7-SuRNA group were svgnificantly lower than control group (P Hep-2 cells. The proliferation of Hep-2 cells was significantly inhibited after transfection (P Hep-2 cells can be inhibited by siRNA mediated EGFL7 gene silencing.

  9. Objective Quantification of Immune Cell Infiltrates and Epidermal Proliferation in Psoriatic Skin

    DEFF Research Database (Denmark)

    Soendergaard, Christoffer; Nielsen, Ole H; Skak, Kresten;

    2015-01-01

    research. Published data of manual cell counts in psoriatic skin samples were in this study reevaluated using the digital image analysis (DIA) software. Whole slides immunohistochemically stained for CD3, CD4, CD8, CD45R0, and Ki-67 were scanned and quantitatively evaluated using simple threshold analysis......Digital pathology and image analysis have developed extensively during the last couple of years. Especially the advance in whole-slide scanning, software, and computer processing makes it possible to apply these methods in tissue-based research. Today this task is dominated by tedious manual...

  10. Multiple Mechanisms are Responsible for Transactivation of the Epidermal Growth Factor Receptor in Mammary Epithelial Cells

    Energy Technology Data Exchange (ETDEWEB)

    Rodland, Karin D.; Bollinger, Nikki; Ippolito, Danielle L.; Opresko, Lee; Coffey, Robert J.; Zangar, Richard C.; Wiley, H. S.

    2008-11-14

    REVIEW ENTIRE DOCUMENT AT: https://pnlweb.pnl.gov/projects/bsd/ERICA%20Manuscripts%20for%20Review/KD%20Rodland%20D7E80/HMEC_transactivation_ms01_15+Figs.pdf ABSTRACT: Using a single nontransformed strain of human mammary epithelial cells, we found that the ability of multiple growth factors and cytokines to induce ERK phosphorylation was dependent on EGFR activity. These included lysophosphatidic acid (LPA), uridine triphosphate, growth hormone, vascular endothelial growth factor, insulin-like growth factor-1 (IGF-1), and tumor necrosis factoralpha. In contrast, hepatocyte growth factor could stimulate ERK phosphorylation independent of EGFR activity...

  11. Dermal fibroblast expression of stromal cell-derived factor-1 (SDF-1) promotes epidermal keratinocyte proliferation in normal and diseased skin.

    Science.gov (United States)

    Quan, Chunji; Cho, Moon Kyun; Shao, Yuan; Mianecki, Laurel E; Liao, Eric; Perry, Daniel; Quan, Taihao

    2015-12-01

    Stromal cells provide a crucial microenvironment for overlying epithelium. Here we investigated the expression and function of a stromal cell-specific protein, stromal cell-derived factor-1 (SDF-1), in normal human skin and in the tissues of diseased skin. Immunohistology and laser capture microdissection (LCM)-coupled quantitative real-time RT-PCR revealed that SDF-1 is constitutively and predominantly expressed in dermal stromal cells in normal human skin in vivo. To our surprise, an extremely high level of SDF-1 transcription was observed in the dermis of normal human skin in vivo, evidenced by much higher mRNA expression level than type I collagen, the most abundant and highly expressed protein in human skin. SDF-1 was also upregulated in the tissues of many human skin disorders including psoriasis, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC). Double immunostaining for SDF-1 and HSP47 (heat shock protein 47), a marker of fibroblasts, revealed that fibroblasts were the major source of stroma-cell-derived SDF-1 in both normal and diseased skin. Functionally, SDF-1 activates the ERK (extracellular-signal-regulated kinases) pathway and functions as a mitogen to stimulate epidermal keratinocyte proliferation. Both overexpression of SDF-1 in dermal fibroblasts and treatment with rhSDF-1 to the skin equivalent cultures significantly increased the number of keratinocyte layers and epidermal thickness. Conversely, the stimulative function of SDF-1 on keratinocyte proliferation was nearly completely eliminated by interfering with CXCR4, a specific receptor of SDF-1, or by knock-down of SDF-1 in fibroblasts. Our data reveal that extremely high levels of SDF-1 provide a crucial microenvironment for epidermal keratinocyte proliferation in both physiologic and pathologic skin conditions.

  12. Differential requirement for CCR4 in the maintenance but not establishment of the invariant Vγ5(+ dendritic epidermal T-cell pool.

    Directory of Open Access Journals (Sweden)

    Kyoko Nakamura

    Full Text Available Thymocytes expressing the invariant Vγ5 γδT-cell receptor represent progenitors of dendritic epidermal T-cells (DETC that play an important immune surveillance role in the skin. In contrast to the bulk of αβT-cell development, Vγ5(+ DETC progenitor development occurs exclusively in fetal thymus. Whilst αβT-cell development is known to require chemokine receptor mediated migration through distinct thymus regions, culminating in medullary entry and thymic egress, the importance and control of intrathymic migration for DETC progenitors is unclear. We recently revealed a link between Vγ5(+ DETC progenitor development and medullary thymic epithelial cells expressing Aire, a known regulator of thymic chemokine expression, demonstrating that normal Vγ5(+ DETC progenitor development requires regulated intramedullary positioning. Here we investigate the role of chemokines and their receptors during intrathymic Vγ5(+ DETC progenitor development and establishment of the DETC pool in the skin. We report that thymic medullary accumulation of Vγ5(+ DETC progenitors is a G-protein coupled receptor dependent process. However, this process occurs independently of Aire's influences on intrathymic chemokines, and in the absence of CCR4 and CCR7 expression by DETC progenitors. In contrast, analysis of epidermal γδT-cells at neonatal and adult stages in CCR4(-/- mice reveals that reduced numbers of DETC in adult epidermis are not a consequence of diminished intrathymic embryonic development, nor deficiencies in initial epidermal seeding in the neonate. Collectively, our data reveal differences in the chemokine receptor requirements for intrathymic migration of αβ and invariant γδT-cells, and highlight a differential role for CCR4 in the maintenance, but not initial seeding, of DETC in the epidermis.

  13. In Vivo Quantification of Peroxisome Tethering to Chloroplasts in Tobacco Epidermal Cells Using Optical Tweezers.

    Science.gov (United States)

    Gao, Hongbo; Metz, Jeremy; Teanby, Nick A; Ward, Andy D; Botchway, Stanley W; Coles, Benjamin; Pollard, Mark R; Sparkes, Imogen

    2016-01-01

    Peroxisomes are highly motile organelles that display a range of motions within a short time frame. In static snapshots, they can be juxtaposed to chloroplasts, which has led to the hypothesis that they are physically interacting. Here, using optical tweezers, we tested the dynamic physical interaction in vivo. Using near-infrared optical tweezers combined with TIRF microscopy, we were able to trap peroxisomes and approximate the forces involved in chloroplast association in vivo in tobacco (Nicotiana tabacum) and observed weaker tethering to additional unknown structures within the cell. We show that chloroplasts and peroxisomes are physically tethered through peroxules, a poorly described structure in plant cells. We suggest that peroxules have a novel role in maintaining peroxisome-organelle interactions in the dynamic environment. This could be important for fatty acid mobilization and photorespiration through the interaction with oil bodies and chloroplasts, highlighting a fundamentally important role for organelle interactions for essential biochemistry and physiological processes. © 2016 American Society of Plant Biologists. All Rights Reserved.

  14. Dermatite solar felina associada a carcinoma epidermóide Felinesolar dermatitis associated to squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Alonso Gabriel Pereira Guedes

    1998-12-01

    Full Text Available A pele é um dos maiores sistemas do organismo animal, desempenhando importantes papéis e apresenta inúmeras alterações que, freqüentemente, levam os proprietários de animais domésticos a procurar os serviços veterinários. A dermatite solar felina é uma doença de natureza ambiental, que acomete gatos brancos ou aqueles que possuem áreas despigmentadas, principalmente nas orelhas e nariz. Esta doença, causada pela exposição da pele despigmentada à radiação ultravioleta, pode evoluir para carcinoma epidermóide nos casos de exposição por período prolongado. A lesão inicia-se com severo eritema da orelha, progredindo para descamação cutânea e formação de crostas marginais. O controle objetiva evitar o contado da pele despigmentada com a luz solar, principalmente nas horas mais quentes do dia. Para se atingir este objetivo, deve-se evitar que os animais entrem em contato com o sol, mantendo-os presos em horários estratégicos, utilizando filtros solares à base de creme ou ainda confeccionando tatuagens nas áreas despigmentadas. Após a instalação do carcinoma epidermóide, diferentes métodos terapêuticos são recomendados para o tratamento, dentre eles a cirurgia, com remoção total dos tecidos atingidos pela neoplasia, a radioterapia, a fotoquimioterapia, a hipertermia e a terapia com glicocorticóides.The skin constitutes one of the largest systems of the body, performing outstanding duties and being the site of numerous changes that induce the owners to come after the veterinary services. The feline solar dermatitis is an environmental disease that affects white cats or cats with white skin areas mainly on the nose and ears. This disease is caused by the skin exposition to ultra-violet (UV radiation and may envolve to a squamous cell carcinoma when a prolonged exposition period takes place. Initially, the lesions consists of severe erythema of the ear evolving to scaling and formation of a marginal crust

  15. Tyrosine kinase inhibitors for epidermal growth factor receptor gene mutation-positive non-small cell lung cancers: an update for recent advances in therapeutics.

    Science.gov (United States)

    Chung, Clement

    2016-06-01

    The presence of activating gene mutations in the epidermal growth factor receptor of non-small cell lung cancer patients is predictive (improved progression-free survival and improved response rate) when treated with small molecule tyrosine kinase inhibitors such as gefitinib, erlotinib and afatinib. The two most common mutations that account for greater than 85% of all EGFR gene mutations are in-frame deletions in exon 19 (LREA deletions) and substitution in exon 21 (L858R). Exon 18 mutations occur much less frequently at about 4% of all EGFR gene mutations. Together, exon 19 deletion and exon 21 L858R gene substitution are present in about 10% of Caucasian patients and 20-40% of Asian patients with non-small cell lung cancer. T790M gene mutation at exon 20 is associated with acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitors. Early studies showed that activating EGFR gene mutations are most common in patients with adenocarcinoma histology, women, never smokers and those of Asian ethnicity. A recent multi-center phase III trial suggested that frontline epidermal growth factor receptor tyrosine kinase inhibitor therapy with afatinib is associated with improved progression-free survival compared to chemotherapy regardless of race. Moreover, guidelines now suggest EGFR gene mutation testing should be conducted in all patients with lung adenocarcinoma or mixed lung cancers with an adenocarcinoma component, regardless of characteristics such as smoking status, gender or race. The success of targeted therapies in non-small cell lung cancer patients has changed the treatment paradigm in metastatic non-small cell lung cancer. However, despite a durable response of greater than a year, resistance to epidermal growth factor receptor tyrosine kinase inhibitors inevitably occurs. This mini-review describes the clinically relevant EGFR gene mutations and the efficacy/toxicity of small molecule epidermal growth factor receptor tyrosine kinase

  16. Epidermal growth factor-like domain 7 promotes migration and invasion of human trophoblast cells through activation of MAPK, PI3K and NOTCH signaling pathways.

    Science.gov (United States)

    Massimiani, M; Vecchione, L; Piccirilli, D; Spitalieri, P; Amati, F; Salvi, S; Ferrazzani, S; Stuhlmann, H; Campagnolo, L

    2015-05-01

    Epidermal growth factor-like domain 7 (Egfl7) is a gene that encodes a partially secreted protein and whose expression is largely restricted to the endothelia. We recently reported that EGFL7 is also expressed by trophoblast cells in mouse and human placentas. Here, we investigated the molecular pathways that are regulated by EGFL7 in trophoblast cells. Stable EGFL7 overexpression in a Jeg3 human choriocarcinoma cell line resulted in significantly increased cell migration and invasiveness, while cell proliferation was unaffected. Analysis of mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) pathways showed that EGFL7 promotes Jeg3 cell motility by activating both pathways. We show that EGFL7 activates the epidermal growth factor receptor (EGFR) in Jeg3 cells, resulting in downstream activation of extracellular regulated kinases (ERKs). In addition, we provide evidence that EGFL7-triggered migration of Jeg3 cells involves activation of NOTCH signaling. EGFL7 and NOTCH1 are co-expressed in Jeg3 cells, and blocking of NOTCH activation abrogates enhanced migration of Jeg3 cells overexpressing EGFL7. We also demonstrate that signaling through EGFR and NOTCH converged to mediate EGFL7 effects. Reduction of endogenous EGFL7 expression in Jeg3 cells significantly decreased cell migration. We further confirmed that EGFL7 stimulates cell migration by using primary human first trimester trophoblast (PTB) cells overexpressing EGFL7. In conclusion, our data suggest that in trophoblast cells, EGFL7 regulates cell migration and invasion by activating multiple signaling pathways. Our results provide a possible explanation for the correlation between reduced expression of EGFL7 and inadequate trophoblast invasion observed in placentopathies.

  17. IL-1β-Dependent Activation of Dendritic Epidermal T Cells in Contact Hypersensitivity

    DEFF Research Database (Denmark)

    Nielsen, Morten M; Lovato, Paola; Macleod, Amanda S

    2014-01-01

    in CHS. Thus, more IL-17-producing DETCs appear in the skin following exposure to DNFB in wild-type mice, and DNFB-induced ear swelling is reduced by ∼50% in TCRδ(-/-) mice compared with wild-type mice. In accordance, DNFB-induced ear swelling was reduced by ∼50% in IL-17(-/-) mice. We show that DNFB...... responses, as measured by decreased ear swelling, inhibition of local DETC activation, and a reduction in the number of IL-17(+) γδ T cells and DETCs in the draining lymph nodes. Taken together, we show that DETCs become activated and produce IL-17 in an IL-1β-dependent manner during CHS, suggesting a key...

  18. Topical retinoic acid changes the epidermal cell surface glycosylation pattern towards that of a mucosal epithelium

    DEFF Research Database (Denmark)

    Griffiths, C E; Dabelsteen, Erik; Voorhees, J J

    1996-01-01

    in the epidermis and in oral mucosal epithelium. Although type 1 chain structures were not demonstrated in any of the samples, the distribution of type 2 and 3 chain structures in RA-treated epidermis was altered towards that seen in a mucosal epithelium. T antigen, a mucin-type cell surface carbohydrate structure...... normally expressed throughout the epidermis, was only observed in the granular layer of RA-treated epidermis--a feature of mucosal epithelia. Ley, normally only seen in non-keratinized buccal epithelium, was strongly expressed in RA-treated epidermis. In contrast, the glycosylation pattern of the SLS......-treated epidermis was not significantly different from that observed after vehicle treatment. Thus, RA treatment converts normal stratified epithelium towards the phenotype of mucosal epithelium with a decrease in T antigen and a concomitant increase in Ley. These changes are not observed following treatment...

  19. MMP-1 and MMP-9 regulate epidermal growth factor-dependent collagen loss in human carotid plaque smooth muscle cells.

    Science.gov (United States)

    Rao, Velidi H; Kansal, Vikash; Stoupa, Samantha; Agrawal, Devendra K

    2014-02-01

    Mechanisms underlying the rupture of atherosclerotic plaque, a crucial factor in the development of myocardial infarction and stroke, are not well defined. Here, we examined the role of epidermal growth factor (EGF)-mediated matrix metalloproteinases (MMP) on the stability of interstitial collagens in vascular smooth muscle cells (VSMCs) isolated from carotid endarterectomy tissues of symptomatic and asymptomatic patients with carotid stenosis. VSMCs isolated from the carotid plaques of both asymptomatic and symptomatic patients were treated with EGF. The MMP-9 activity was quantified by gelatin zymography and the analysis of mRNA transcripts and protein for MMP-9, MMP-1, EGFR and collagen types I, Col I(α1) and collagen type III, Col III(α1) were analyzed by qPCR and immunofluorescence, respectively. The effect of EGF treatment to increase MMP-9 activity and mRNA transcripts for MMP-9, MMP-1, and EGFR and to decrease mRNA transcripts for Col I(α1) and Col III(α1) was threefold to fourfold greater in VSMCs isolated from the carotid plaques of symptomatic than asymptomatic patients. Inhibitors of EGFR (AG1478) and a small molecule inhibitor of MMP-9 decreased the MMP9 expression and upregulated Col I(α1) and Col III(α1) in EGF-treated VSMCs of both groups. Additionally, the magnitude in decreased MMP-9 mRNA and increased Col I(α1) and Col III(α1) due to knockdown of MMP-9 gene with siRNA in EGF-treated VSMCs was significantly greater in the symptomatic group than the asymptomatic group. Thus, a selective blockade of both EGFR and MMP-9 may be a novel strategy and a promising target for stabilizing vulnerable plaques in patients with carotid stenosis.

  20. Epigenetic modifications of triterpenoid ursolic acid in activating Nrf2 and blocking cellular transformation of mouse epidermal cells.

    Science.gov (United States)

    Kim, Hyuck; Ramirez, Christina N; Su, Zheng-Yuan; Kong, Ah-Ng Tony

    2016-07-01

    Ursolic acid (UA), a well-known natural triterpenoid found in abundance in blueberries, cranberries and apple peels, has been reported to possess many beneficial health effects. These effects include anticancer activity in various cancers, such as skin cancer. Skin cancer is the most common cancer in the world. Nuclear factor E2-related factor 2 (Nrf2) is a master regulator of antioxidative stress response with anticarcinogenic activity against UV- and chemical-induced tumor formation in the skin. Recent studies show that epigenetic modifications of Nrf2 play an important role in cancer prevention. However, the epigenetic impact of UA on Nrf2 signaling remains poorly understood in skin cancer. In this study, we investigated the epigenetic effects of UA on mouse epidermal JB6 P+ cells. UA inhibited cellular transformation by 12-O-tetradecanoylphorbol-13-acetate at a concentration at which the cytotoxicity was no more than 25%. Under this condition, UA induced the expression of the Nrf2-mediated detoxifying/antioxidant enzymes heme oxygenase-1, NAD(P)H:quinone oxidoreductase 1 and UDP-glucuronosyltransferase 1A1. DNA methylation analysis revealed that UA demethylated the first 15 CpG sites of the Nrf2 promoter region, which correlated with the reexpression of Nrf2. Furthermore, UA reduced the expression of epigenetic modifying enzymes, including the DNA methyltransferases DNMT1 and DNMT3a and the histone deacetylases (HDACs) HDAC1, HDAC2, HDAC3 and HDAC8 (Class I) and HDAC6 and HDAC7 (Class II), and HDAC activity. Taken together, these results suggest that the epigenetic effects of the triterpenoid UA could potentially contribute to its beneficial effects, including the prevention of skin cancer.

  1. Association between thyroid cancer and epidermal growth factor receptor mutation in female with nonsmall cell lung cancer

    Science.gov (United States)

    Kim, Seo Yun; Kim, Hye-Ryoun; Kim, Cheol Hyeon; Koh, Jae Soo; Baek, Hee Jong; Choi, Chang-Min; Song, Joon Seon; Lee, Jae Cheol; Na, Im II

    2017-01-01

    BACKGROUND: The aim of this study was to investigate the association between epidermal growth factor receptor (EGFR) mutation and thyroid cancer in female patients with nonsmall-cell lung cancer (NSCLC). METHODS: In a retrospective study, we examined 835 female patients who were diagnosed with NSCLC and underwent an EGFR mutation test between June 2003 and August 2013. The associations of EGFR mutation with thyroid cancer and a family history of thyroid cancer were evaluated using logistic regression models. RESULTS: EGFR mutation was found in 378 of 835 patients. In addition to adenocarcinoma (P cancer (5.8% versus 2.6%; P = 0.020), while showing a trend toward inverse association with a personal history of nonthyroid cancer (5.8% vs. 9.0%; P = 0.086). Likewise, the incidence of EGFR mutations was associated with a family history of thyroid cancer (2.9% vs. 0.9%; P = 0.028), while showing a trend toward inverse association with a family history of nonthyroid cancer (27.8% vs. 33.7%; P = 0.066). Multivariate logistic regression showed that the incidence of EGFR mutations was different in women with thyroid or nonthyroid cancer (P = 0.035) and in women with a family history of thyroid or nonthyroid cancer (P = 0.023). CONCLUSIONS: Our data suggest that thyroid cancer and a family history of thyroid cancer are associated with EGFR-mutated NSCLC in female patients. The differences in the incidence of thyroid cancer and a family history of thyroid cancer by EGFR mutational status provide new insight into pathogenesis of this genetic change.

  2. Epidermal growth factor receptor (EGFR mutations and expression in squamous cell carcinoma of the esophagus in central Asia

    Directory of Open Access Journals (Sweden)

    Abedi-Ardekani Behnoush

    2012-12-01

    Full Text Available Abstract Background Esophageal squamous cell carcinoma (ESCC shows geographic variations in incidence, with high incidences (>50/105 person-years in central Asia, including North Eastern Iran (Golestan and Northern India (Kashmir. In contrast to Western countries, smoking does not appear to be a significant risk factor for ESCC in central Asia. In lung adenocarcinoma, activating mutations in the gene encoding epidermal growth factor receptor (EGFR are frequent in tumors of never smokers of Asian origin, predicting therapeutic sensitivity to Egfr-targeting drugs. Methods In this study 152 cases of histologically confirmed ESCC from Iran (Tehran and Golestan Province and North India (Kashmir Valley have been analyzed for EGFR mutation by direct sequencing of exons 18–21. Egfr protein expression was evaluated by immunohistochemistry in 34 samples from Tehran and HER2 mutations were analyzed in 54 cases from Kashmir. Results A total of 14 (9.2% EGFR variations were detected, including seven variations in exons. Among those, four (2.6% were already documented in lung cancers, two were reported as polymorphisms and one was a potentially new activating mutation. All but one variation in introns were previously identified as polymorphisms. Over-expression of Egfr was detected in 22/34 (65% of tested cases whereas no HER2 mutation was found in 54 cases from Kashmir. Conclusion Overall, EGFR mutations appear to be a rare event in ESCC in high incidence areas of central Asia, although a very small proportion of cases may harbor mutations predicting sensitivity to anti-Egfr drugs.

  3. Retreatment with Epidermal Growth Factor Receptor Inhibitor After Initial Failure in Advanced Non-small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Tongtong AN

    2011-03-01

    Full Text Available Background and objective The epidermal growth factor receptor tyrosine kinase inhibitor (EGFRTKI shows favorable antitumor activity against chemorefractory non-small cell lung cancer (NSCLC. However, patients with advanced NSCLC have limited treatment options available if they are refractory to EGFR-TKI. To study the influence of the retreatment EGFR-TKI after failure of first-line TKI, we carried out this retrospective study. Methods Total 71 patients were analyzed who experienced treatment failure from their initial use of EGFR-TKI. After a period of time, they were retreated with TKI as tumor progression was observed. Results Of the 71 patients who received retreatment TKI, it was observed in 7% in partial response (PR, 36.6% in stable disease (SD, 56.3% in progressive disease (PD. Disease control rate (DCR was 43.7%. Twenty-six (36.6% patients were well controlled by retreatment with TKI monotherapy for not less than 3 months. Five (7.0% patients had partial response. Exon 21 mutation, PFS not less than 6 months during initial treatment TKI, and the interval not less than 3 months between initial treatment, and retreatment with TKI was associated with a good progression free survival based on univariate COX analysis (P=0.034; P=0.013; P=0.046. Conclusion It has been shown the possibility that retreatment with TKI might be useful when (1 Exon 21 has active mutation, (2 initial treatment shows a favorable PFS (≥ 6 months, and (3 there has been a period of time (≥3 months following the termination of the initial TKI treatment.

  4. UV-induced mutations in epidermal cells of mice defective in DNA polymerase η and/or ι.

    Science.gov (United States)

    Kanao, Rie; Yokoi, Masayuki; Ohkumo, Tsuyoshi; Sakurai, Yasutaka; Dotsu, Kantaro; Kura, Shinobu; Nakatsu, Yoshimichi; Tsuzuki, Teruhisa; Masutani, Chikahide; Hanaoka, Fumio

    2015-05-01

    Xeroderma pigmentosum variant (XP-V) is a human rare inherited recessive disease, predisposed to sunlight-induced skin cancer, which is caused by deficiency in DNA polymerase η (Polη). Polη catalyzes accurate translesion synthesis (TLS) past pyrimidine dimers, the most prominent UV-induced lesions. DNA polymerase ι (Polι) is a paralog of Polη that has been suggested to participate in TLS past UV-induced lesions, but its function in vivo remains uncertain. We have previously reported that Polη-deficient and Polη/Polι double-deficient mice showed increased susceptibility to UV-induced carcinogenesis. Here, we investigated UV-induced mutation frequencies and spectra in the epidermal cells of Polη- and/or Polι-deficient mice. While Polη-deficient mice showed significantly higher UV-induced mutation frequencies than wild-type mice, Polι deficiency did not influence the frequencies in the presence of Polη. Interestingly, the frequencies in Polη/Polι double-deficient mice were statistically lower than those in Polη-deficient mice, although they were still higher than those of wild-type mice. Sequence analysis revealed that most of the UV-induced mutations in Polη-deficient and Polη/Polι double-deficient mice were base substitutions at dipyrimidine sites. An increase in UV-induced mutations at both G:C and A:T pairs associated with Polη deficiency suggests that Polη contributes to accurate TLS past both thymine- and cytosine-containing dimers in vivo. A significant decrease in G:C to A:T transition in Polη/Polι double-deficient mice when compared with Polη-deficient mice suggests that Polι is involved in error-prone TLS past cytosine-containing dimers when Polη is inactivated.

  5. The cotton transcription factor TCP14 functions in auxin-mediated epidermal cell differentiation and elongation.

    Science.gov (United States)

    Wang, Miao-Ying; Zhao, Pi-Ming; Cheng, Huan-Qing; Han, Li-Bo; Wu, Xiao-Min; Gao, Peng; Wang, Hai-Yun; Yang, Chun-Lin; Zhong, Nai-Qin; Zuo, Jian-Ru; Xia, Gui-Xian

    2013-07-01

    Plant-specific TEOSINTE-BRANCHED1/CYCLOIDEA/PCF (TCP) transcription factors play crucial roles in development, but their functional mechanisms remain largely unknown. Here, we characterized the cellular functions of the class I TCP transcription factor GhTCP14 from upland cotton (Gossypium hirsutum). GhTCP14 is expressed predominantly in fiber cells, especially at the initiation and elongation stages of development, and its expression increased in response to exogenous auxin. Induced heterologous overexpression of GhTCP14 in Arabidopsis (Arabidopsis thaliana) enhanced initiation and elongation of trichomes and root hairs. In addition, root gravitropism was severely affected, similar to mutant of the auxin efflux carrier PIN-FORMED2 (PIN2) gene. Examination of auxin distribution in GhTCP14-expressing Arabidopsis by observation of auxin-responsive reporters revealed substantial alterations in auxin distribution in sepal trichomes and root cortical regions. Consistent with these changes, expression of the auxin uptake carrier AUXIN1 (AUX1) was up-regulated and PIN2 expression was down-regulated in the GhTCP14-expressing plants. The association of GhTCP14 with auxin responses was also evidenced by the enhanced expression of auxin response gene IAA3, a gene in the AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) family. Electrophoretic mobility shift assays showed that GhTCP14 bound the promoters of PIN2, IAA3, and AUX1, and transactivation assays indicated that GhTCP14 had transcription activation activity. Taken together, these results demonstrate that GhTCP14 is a dual-function transcription factor able to positively or negatively regulate expression of auxin response and transporter genes, thus potentially acting as a crucial regulator in auxin-mediated differentiation and elongation of cotton fiber cells.

  6. Streptococcus pyogenes-induced cutaneous lymphocyte antigen-positive T cell-dependent epidermal cell activation triggers TH17 responses in patients with guttate psoriasis.

    Science.gov (United States)

    Ruiz-Romeu, Ester; Ferran, Marta; Sagristà, Marc; Gómez, Julià; Giménez-Arnau, Ana; Herszenyi, Krisztina; Hóllo, Péter; Celada, Antonio; Pujol, Ramon; Santamaria-Babí, Luis F

    2016-08-01

    Guttate psoriasis (GP) is characterized by acute onset of small, rounded psoriatic lesions. Although this particular phenotype of psoriasis is usually associated with streptococcal throat infections and mainly occurs in HLA-Cw6(+) patients, the specific immunologic response to this innate stimulus that causes these skin lesions is poorly understood. This study aims to elucidate how key cellular elements of patients with GP respond to Streptococcus pyogenes and whether this initial immune response is favored by the genetic and environmental background of these patients. Circulating memory T cells and autologous epidermal cells from samples from either patients with GP (n = 14) or healthy control subjects (n = 6) were cocultured ex vivo in the presence of an S pyogenes extract. Levels of the psoriasis-associated cytokines IL-17A, IL-17F, IFN-γ, TNF-α, IL-6, and IL-8 were determined. The expression of several genes with increased (DEFB4, S100A7, LCN2, IL36G, IL8, CXCL9, CXCL10, and CXCL11) or decreased (FLG and LOR) transcripts in psoriatic lesions was examined in keratinocytes treated with coculture supernatants. When skin-homing effector memory cutaneous lymphocyte antigen-positive T cells were used in cocultures, a TH17-dominant response was observed, as reflected by the higher amounts of IL-17A and IL-17F than IFN-γ. Moreover, a higher TH17 response was observed in cells isolated from patients with flares associated with a streptococcal tonsillitis and with the HLA-Cw6 allele (cohort 1). In addition, in normal keratinocytes the supernatants from these cocultures induced an increase in IL-17-associated genes, such as DEFB4, S100A7, LCN2, IL36G, and IL8 but a decrease in FLG and LOR, thereby confirming the role of activated TH17 cells. This study reveals a dominant TH17 response of cutaneous lymphocyte antigen-positive T cells activated by epidermal cells and S pyogenes in patients with GP. Copyright © 2016 American Academy of Allergy, Asthma

  7. Isolation and Identification of Rat Epidermal Stem Cells%大鼠表皮干细胞的分离及鉴定

    Institute of Scientific and Technical Information of China (English)

    郭延敏

    2012-01-01

    Direct-tissue culturing was used to isolate and culture rat epidermal stem cells. Then, observe the appearance of the culturing cells, and the expression of CK15, P63 and α6-integrin in ESCs were detected by immunohistochemistry staining. By the way, the ESCs marked by α6-integrin were detected by flow cytometry CFCM). Meanwhile, the growth curve of epidermal stem cells was also detected. We could isolate, purify and culture rat epidermal stem cells successfully by direct-tissue culturing method and these cells grew well. Immuno-histochemistry staining showed that CK15, P63 and α6-integrin were strongly expressed in the cultured epidermal stem cells. According to the flow cytometry, the probability of Micky cells marked by 06-integrin was 80% , while the probability of unsticky cells marked by a6-integrin was only 2%.%在试验中采用组织块法分离培养大鼠表皮干细胞,观察所培养的细胞形态,免疫组织化学方法检测CK15、P63、α6-integrin表达情况并用α6-integrin标记表皮干细胞经流式细胞仪检测其标记率,同时对1~6代表皮干细胞在不同培养时间计数.结果表明,采用组织块法能分离得到大鼠表皮干细胞,且获得的细胞生长良好;干细胞标记物CK15、α6-integrin、P63呈阳性.经流式细胞仪检测得知,黏附细胞被α6-integrin标记的几率为80%,而未黏附细胞被α6-integrin标记的几率仅为2%,二者相差较大.

  8. Expression Levels of Some Antioxidant and Epidermal Growth Factor Receptor Genes in Patients with Early-Stage Non-Small Cell Lung Cancer

    Science.gov (United States)

    De Palma, Giuseppe; Mozzoni, Paola; Acampa, Olga; Internullo, Eveline; Carbognani, Paolo; Rusca, Michele; Goldoni, Matteo; Corradi, Massimo; Tiseo, Marcello; Apostoli, Pietro; Mutti, Antonio

    2010-01-01

    This study was aimed at: (i) investigating the expression profiles of some antioxidant and epidermal growth factor receptor genes in cancerous and unaffected tissues of patients undergoing lung resection for non-small cell lung cancer (NSCLC) (cross-sectional phase), (ii) evaluating if gene expression levels at the time of surgery may be associated to patients' survival (prospective phase). Antioxidant genes included heme oxygenase 1 (HO-1), superoxide dismutase-1 (SOD-1), and -2 (SOD-2), whereas epidermal growth factor receptor genes consisted of epidermal growth factor receptor (EGFR) and v-erb-b2 erythroblastic leukaemia viral oncogene homolog 2 (HER-2). Twenty-eight couples of lung biopsies were obtained and gene transcripts were quantified by Real Time RT-PCR. The average follow-up of patients lasted about 60 months. In the cancerous tissues, antioxidant genes were significantly hypo-expressed than in unaffected tissues. The HER-2 transcript levels prevailed in adenocarcinomas, whereas EGFR in squamocellular carcinomas. Patients overexpressing HER-2 in the cancerous tissues showed significantly lower 5-year survival than the others. PMID:20700416

  9. Expression levels of some antioxidant and epidermal growth factor receptor genes in patients with early-stage non-small cell lung cancer.

    Science.gov (United States)

    De Palma, Giuseppe; Mozzoni, Paola; Acampa, Olga; Internullo, Eveline; Carbognani, Paolo; Rusca, Michele; Goldoni, Matteo; Corradi, Massimo; Tiseo, Marcello; Apostoli, Pietro; Mutti, Antonio

    2010-01-01

    THIS STUDY WAS AIMED AT: (i) investigating the expression profiles of some antioxidant and epidermal growth factor receptor genes in cancerous and unaffected tissues of patients undergoing lung resection for non-small cell lung cancer (NSCLC) (cross-sectional phase), (ii) evaluating if gene expression levels at the time of surgery may be associated to patients' survival (prospective phase). Antioxidant genes included heme oxygenase 1 (HO-1), superoxide dismutase-1 (SOD-1), and -2 (SOD-2), whereas epidermal growth factor receptor genes consisted of epidermal growth factor receptor (EGFR) and v-erb-b2 erythroblastic leukaemia viral oncogene homolog 2 (HER-2). Twenty-eight couples of lung biopsies were obtained and gene transcripts were quantified by Real Time RT-PCR. The average follow-up of patients lasted about 60 months. In the cancerous tissues, antioxidant genes were significantly hypo-expressed than in unaffected tissues. The HER-2 transcript levels prevailed in adenocarcinomas, whereas EGFR in squamocellular carcinomas. Patients overexpressing HER-2 in the cancerous tissues showed significantly lower 5-year survival than the others.

  10. NASA-approved rotary bioreactor enhances proliferation of human epidermal stem cells and supports formation of 3D epidermis-like structure.

    Directory of Open Access Journals (Sweden)

    Xiao-hua Lei

    Full Text Available The skin is susceptible to different injuries and diseases. One major obstacle in skin tissue engineering is how to develop functional three-dimensional (3D substitute for damaged skin. Previous studies have proved a 3D dynamic simulated microgravity (SMG culture system as a "stimulatory" environment for the proliferation and differentiation of stem cells. Here, we employed the NASA-approved rotary bioreactor to investigate the proliferation and differentiation of human epidermal stem cells (hEpSCs. hEpSCs were isolated from children foreskins and enriched by collecting epidermal stem cell colonies. Cytodex-3 micro-carriers and hEpSCs were co-cultured in the rotary bioreactor and 6-well dish for 15 days. The result showed that hEpSCs cultured in rotary bioreactor exhibited enhanced proliferation and viability surpassing those cultured in static conditions. Additionally, immunostaining analysis confirmed higher percentage of ki67 positive cells in rotary bioreactor compared with the static culture. In contrast, comparing with static culture, cells in the rotary bioreactor displayed a low expression of involucrin at day 10. Histological analysis revealed that cells cultured in rotary bioreactor aggregated on the micro-carriers and formed multilayer 3D epidermis structures. In conclusion, our research suggests that NASA-approved rotary bioreactor can support the proliferation of hEpSCs and provide a strategy to form multilayer epidermis structure.

  11. micro RNA 172 (miR172) signals epidermal infection and is expressed in cells primed for bacterial invasion in Lotus japonicus roots and nodules.

    Science.gov (United States)

    Holt, Dennis B; Gupta, Vikas; Meyer, Dörte; Abel, Nikolaj B; Andersen, Stig U; Stougaard, Jens; Markmann, Katharina

    2015-10-01

    Legumes interact with rhizobial bacteria to form nitrogen-fixing root nodules. Host signalling following mutual recognition ensures a specific response, but is only partially understood. Focusing on the stage of epidermal infection with Mesorhizobium loti, we analysed endogenous small RNAs (sRNAs) of the model legume Lotus japonicus to investigate their involvement in host response regulation. We used Illumina sequencing to annotate the L. japonicus sRNA-ome and isolate infection-responsive sRNAs, followed by candidate-based functional characterization. Sequences from four libraries revealed 219 novel L. japonicus micro RNAs (miRNAs) from 114 newly assigned families, and 76 infection-responsive sRNAs. Unlike infection-associated coding genes such as NODULE INCEPTION (NIN), a micro RNA 172 (miR172) isoform showed strong accumulation in dependency of both Nodulation (Nod) factor and compatible rhizobia. The genetics of miR172 induction support the existence of distinct epidermal and cortical signalling events. MIR172a promoter activity followed a previously unseen pattern preceding infection thread progression in epidermal and cortical cells. Nodule-associated miR172a expression was infection-independent, representing the second of two genetically separable activity waves. The combined data provide a valuable resource for further study, and identify miR172 as an sRNA marking successful epidermal infection. We show that miR172 acts upstream of several APETALA2-type (AP2) transcription factors, and suggest that it has a role in fine-tuning AP2 levels during bacterial symbiosis. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  12. Cytotoxicity of HBD3 for dendritic cells, normal human epidermal keratinocytes, hTERT keratinocytes, and primary oral gingival epithelial keratinocytes in cell culture conditions.

    Science.gov (United States)

    Leelakanok, Nattawut; Fischer, Carol L; Bates, Amber M; Guthmiller, Janet M; Johnson, Georgia K; Salem, Aliasger K; Brogden, Kim A; Brogden, Nicole K

    2015-12-03

    Human β-defensin 3 (HBD3) is a prominent host defense peptide. In our recent work, we observed that HBD3 modulates pro-inflammatory agonist-induced chemokine and cytokine responses in human myeloid dendritic cells (DCs), often at 20.0 μM concentrations. Since HBD3 can be cytotoxic in some circumstances, it is necessary to assess its cytotoxicity for DCs, normal human epidermal keratinocytes (NHEKs), human telomerase reverse transcriptase (hTERT) keratinocytes, and primary oral gingival epithelial (GE) keratinocytes in different cell culture conditions. Cells, in serum free media with resazurin and in complete media with 10% fetal bovine serum and resazurin, were incubated with 5, 10, 20, and 40 μM HBD3. Cytotoxicity was determined by measuring metabolic conversion of resazurin to resorufin. The lethal dose 50 (LD50, mean μM±Std Err) values were determined from the median fluorescent intensities of test concentrations compared to live and killed cell controls. The LD50 value range of HBD3 was 18.2-35.9 μM in serum-free media for DCs, NHEKs, hTERT keratinocytes, and GE keratinocytes, and >40.0 μM in complete media. Thus, HBD3 was cytotoxic at higher concentrations, which must be considered in future studies of HBD3-modulated chemokine and cytokine responses in vitro. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Serum response factor controls transcriptional network regulating epidermal function and hair follicle morphogenesis.

    Science.gov (United States)

    Lin, Congxing; Hindes, Anna; Burns, Carole J; Koppel, Aaron C; Kiss, Alexi; Yin, Yan; Ma, Liang; Blumenberg, Miroslav; Khnykin, Denis; Jahnsen, Frode L; Crosby, Seth D; Ramanan, Narendrakumar; Efimova, Tatiana

    2013-03-01

    Serum response factor (SRF) is a transcription factor that regulates the expression of growth-related immediate-early, cytoskeletal, and muscle-specific genes to control growth, differentiation, and cytoskeletal integrity in different cell types. To investigate the role for SRF in epidermal development and homeostasis, we conditionally knocked out SRF in epidermal keratinocytes. We report that SRF deletion disrupted epidermal barrier function leading to early postnatal lethality. Mice lacking SRF in epidermis displayed morphogenetic defects, including an eye-open-at-birth phenotype and lack of whiskers. SRF-null skin exhibited abnormal morphology, hyperplasia, aberrant expression of differentiation markers and transcriptional regulators, anomalous actin organization, enhanced inflammation, and retarded hair follicle (HF) development. Transcriptional profiling experiments uncovered profound molecular changes in SRF-null E17.5 epidermis and revealed that many previously identified SRF target CArG box-containing genes were markedly upregulated in SRF-null epidermis, indicating that SRF may function to repress transcription of a subset of its target genes in epidermis. Remarkably, when transplanted onto nude mice, engrafted SRF-null skin lacked hair but displayed normal epidermal architecture with proper expression of differentiation markers, suggesting that although keratinocyte SRF is essential for HF development, a cross-talk between SRF-null keratinocytes and the surrounding microenvironment is likely responsible for the barrier-deficient mutant epidermal phenotype.

  14. In vitro invasion of small-cell lung cancer cell lines correlates with expression of epidermal growth factor receptor

    DEFF Research Database (Denmark)

    Damstrup, L; Rude Voldborg, B; Spang-Thomsen, M;

    1998-01-01

    analysis. In vitro invasion in a Boyden chamber assay was found in all EGFR-positive cell lines, whereas no invasion was detected in the EGFR-negative cell lines. Quantification of the in vitro invasion in 12 selected SCLC cell lines demonstrated that, in the EGFR-positive cell lines, between 5% and 16......-PCR). However, in vitro invasive SCLC cell lines could not be distinguished from non-invasive cell lines based on the expression pattern of these molecules. In six SCLC cell lines, in vitro invasion was also determined in the presence of the EGFR-neutralizing monoclonal antibody mAb528. The addition...... of this antibody resulted in a significant reduction of the in vitro invasion in three selected EGFR-positive cell lines. Our results show that only EGFR-positive SCLC cell lines had the in vitro invasive phenotype, and it is therefore suggested that the EGFR might play an important role for the invasion potential...

  15. ADP-ribosylation factor 1 controls the activation of the phosphatidylinositol 3-kinase pathway to regulate epidermal growth factor-dependent growth and migration of breast cancer cells.

    Science.gov (United States)

    Boulay, Pierre-Luc; Cotton, Mathieu; Melançon, Paul; Claing, Audrey

    2008-12-26

    Activation of intracellular signaling pathways by growth factors is one of the major causes of cancer development and progression. Recent studies have demonstrated that monomeric G proteins of the Ras family are key regulators of cell proliferation, migration, and invasion. Using an invasive breast cancer cell lines, we demonstrate that the ADP-ribosylation factor 1 (ARF1), a small GTPase classically associated with the Golgi, is an important regulator of the biological effects induced by epidermal growth factor. Here, we show that this ARF isoform is activated following epidermal growth factor stimulation and that, in MDA-MB-231 cells, ARF1 is found in dynamic plasma membrane ruffles. Inhibition of endogenous ARF1 expression results in the inhibition of breast cancer cell migration and proliferation. The underlying mechanism involves the activation of the phosphatidylinositol 3-kinase pathway. Our data demonstrate that depletion of ARF1 markedly impairs the recruitment of the phosphatidylinositol 3-kinase catalytic subunit (p110alpha) to the plasma membrane, and the association of the regulatory subunit (p85alpha) to the activated receptor. These results uncover a novel molecular mechanism by which ARF1 regulates breast cancer cell growth and invasion during cancer progression.

  16. Responses of epidermal cell turgor pressure and photosynthetic activity of leaves of the atmospheric epiphyte Tillandsia usneoides (Bromeliaceae) after exposure to high humidity.

    Science.gov (United States)

    Martin, Craig E; Rux, Guido; Herppich, Werner B

    2013-01-01

    It has been well-established that many epiphytic bromeliads of the atmospheric-type morphology, i.e., with leaf surfaces completely covered by large, overlapping, multicellular trichomes, are capable of absorbing water vapor from the atmosphere when air humidity increases. It is much less clear, however, whether this absorption of water vapor can hydrate the living cells of the leaves and, as a consequence, enhance physiological processes in such cells. The goal of this research was to determine if the absorption of atmospheric water vapor by the atmospheric epiphyte Tillandsia usneoides results in an increase in turgor pressure in leaf epidermal cells that subtend the large trichomes, and, by using chlorophyll fluorescence techniques, to determine if the absorption of atmospheric water vapor by leaves of this epiphyte results in increased photosynthetic activity. Results of measurements on living cells of attached leaves of this epiphytic bromeliad, using a pressure probe and of whole-shoot fluorescence imaging analyses clearly illustrated that the turgor pressure of leaf epidermal cells did not increase, and the photosynthetic activity of leaves did not increase, following exposure of the leaves to high humidity air. These results experimentally demonstrate, for the first time, that the absorption of water vapor following increases in atmospheric humidity in atmospheric epiphytic bromeliads is mostly likely a physical phenomenon resulting from hydration of non-living leaf structures, e.g., trichomes, and has no physiological significance for the plant's living tissues.

  17. GEP100/Arf6 is required for epidermal growth factor-induced ERK/Rac1 signaling and cell migration in human hepatoma HepG2 cells.

    Directory of Open Access Journals (Sweden)

    ZhenZhen Hu

    Full Text Available BACKGROUND: Epidermal growth factor (EGF signaling is implicated in the invasion and metastasis of hepatoma cells. However, the signaling pathways for EGF-induced motility of hepatoma cells remain undefined. METHODOLOGY/PRINCIPAL FINDINGS: We found that EGF dose-dependently stimulated the migration of human hepatoma cells HepG2, with the maximal effect at 10 ng/mL. Additionally, EGF increased Arf6 activity, and ectopic expression of Arf6 T27N, a dominant negative Arf6 mutant, largely abolish EGF-induced cell migration. Blocking GEP100 with GEP100 siRNA or GEP100-△PH, a pleckstrin homology (PH domain deletion mutant of GEP100, blocked EGF-induced Arf6 activity and cell migration. EGF also increased ERK and Rac1 activity. Ectopic expression GEP100 siRNA, GEP100-△PH, or Arf6-T27N suppressed EGF-induced ERK and Rac1 activity. Furthermore, blocking ERK signaling with its inhibitor U0126 remarkably inhibited both EGF-induced Rac1 activation as well as cell migration, and ectopic expression of inactive mutant form of Rac1 (Rac1-T17N also largely abolished EGF-induced cell migration. CONCLUSIONS/SIGNIFICANCE: Taken together, this study highlights the function of the PH domain of GEP100 and its regulated Arf6/ERK/Rac1 signaling cascade in EGF-induced hepatoma cell migration. These findings could provide a rationale for designing new therapy based on inhibition of hepatoma metastasis.

  18. Use of a collagen-elastin matrix as transport carrier system to transfer proliferating epidermal cells to human dermis in vitro.

    Science.gov (United States)

    Waaijman, Taco; Breetveld, Melanie; Ulrich, Magda; Middelkoop, Esther; Scheper, Rik J; Gibbs, Susan

    2010-01-01

    This in vitro study describes a novel cell culture, transport, and transfer protocol that may be highly suitable for delivering cultured proliferating keratinocytes and melanocytes to large open skin wounds (e.g., burns). We have taken into account previous limitations identified using other keratinocyte transfer techniques, such as regulatory issues, stability of keratinocytes during transport (single cell suspensions undergo terminal differentiation), ease of handling during application, and the degree of epidermal blistering resulting after transplantation (both related to transplanting keratinocyte sheets). Large numbers of proliferating epidermal cells (EC) (keratinocytes and melanocytes) were generated within 10-14 days and seeded onto a three-dimensional matrix composed of elastin and collagen types I, III, and V (Matriderm®), which enabled easy and stable transport of the EC for up to 24 h under ambient conditions. All culture conditions were in accordance with the regulations set by the Dutch Central Committee on Research Involving Human Subjects (CCMO). As an in vitro model system for clinical in vivo transfer, the EC were then transferred from Matriderm onto human acellular dermis during a period of 3 days. After transfer the EC maintained the ability to regenerate into a fully differentiated epidermis containing melanocytes on the human dermis. Proliferating keratinocytes were located in the basal layer and keratin-10 expression was located in differentiating suprabasal layers similar to that found in human epidermis. No blistering was observed (separation of the epidermis from the basement membrane). Keratin-6 expression was strongly upregulated in the regenerating epidermis similar to normal wound healing. In summary, we show that EC-Matriderm contains viable, metabolically active keratinocytes and melanocytes cultured in a manner that permits easy transportation and contains epidermal cells with the potential to form a pigmented reconstructed

  19. Epidermal Growth Factor Induces Proliferation of Hair Follicle-Derived Mesenchymal Stem Cells Through Epidermal Growth Factor Receptor-Mediated Activation of ERK and AKT Signaling Pathways Associated with Upregulation of Cyclin D1 and Downregulation of p16.

    Science.gov (United States)

    Bai, Tingting; Liu, Feilin; Zou, Fei; Zhao, Guifang; Jiang, Yixu; Liu, Li; Shi, Jiahong; Hao, Deshun; Zhang, Qi; Zheng, Tong; Zhang, Yingyao; Liu, Mingsheng; Li, Shilun; Qi, Liangchen; Liu, Jin Yu

    2017-01-15

    The maintenance of highly proliferative capacity and full differentiation potential is a necessary step in the initiation of stem cell-based regenerative medicine. Our recent study showed that epidermal growth factor (EGF) significantly enhanced hair follicle-derived mesenchymal stem cell (HF-MSC) proliferation while maintaining the multilineage differentiation potentials. However, the underlying mechanism remains unclear. Herein, we investigated the role of EGF in HF-MSC proliferation. HF-MSCs were isolated and cultured with or without EGF. Immunofluorescence staining, flow cytometry, cytochemistry, and western blotting were used to assess proliferation, cell signaling pathways related to the EGF receptor (EGFR), and cell cycle progression. HF-MSCs exhibited surface markers of mesenchymal stem cells and displayed trilineage differentiation potentials toward adipocytes, chondrocytes, and osteoblasts. EGF significantly increased HF-MSC proliferation as well as EGFR, ERK1/2, and AKT phosphorylation (p-EGFR, p-ERK1/2, and p-AKT) in a time- and dose-dependent manner, but not STAT3 phosphorylation. EGFR inhibitor (AG1478), PI3K-AKT inhibitor (LY294002), ERK inhibitor (U0126), and STAT3 inhibitor (STA-21) significantly blocked EGF-induced HF-MSC proliferation. Moreover, AG1478, LY294002, and U0126 significantly decreased p-EGFR, p-AKT, and p-ERK1/2 expression. EGF shifted HF-MSCs at the G1 phase to the S and G2 phase. Concomitantly, cyclinD1, phosphorylated Rb, and E2F1expression increased, while that of p16 decreased. In conclusion, EGF induces HF-MSC proliferation through the EGFR/ERK and AKT pathways, but not through STAT-3. The G1/S transition was stimulated by upregulation of cyclinD1 and inhibition of p16 expression.

  20. Non-small-cell lung cancer cells combat epidermal growth factor receptor tyrosine kinase inhibition through immediate adhesion-related responses

    Directory of Open Access Journals (Sweden)

    Wang HY

    2016-05-01

    Full Text Available Hsian-Yu Wang,1,2 Min-Kung Hsu,3,4 Kai-Hsuan Wang,1 Ching-Ping Tseng,2,4 Feng-Chi Chen,3,4 John T-A Hsu1,4 1Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes (NHRI, Zhunan, Miaoli County, 2Institute of Molecular Medicine and Bioengineering, National Chiao Tung University (NCTU, Hsinchu, 3Division of Biostatistics and Bioinformatics, Institute of Population Health Sciences, National Health Research Institutes (NHRI, Zhunan, Miaoli County, 4Department of Biological Science and Technology, National Chiao Tung University (NCTU, Hsinchu, Taiwan, Republic of China Background: Epidermal growth factor receptor (EGFR tyrosine kinase inhibitors (TKIs, such as gefitinib, erlotinib, and afatinib, have greatly improved treatment efficacy in non-small cell lung cancer (NSCLC patients with drug-sensitive EGFR mutations. However, in some TKI responders, the benefits of such targeted therapies are limited by the rapid development of resistance, and strategies to overcome this resistance are urgently needed. Studies of drug resistance in cancer cells typically involve long term in vitro induction to obtain stably acquired drug-resistant cells followed by elucidation of resistance mechanisms, but the immediate responses of cancer cells upon drug treatment have been ignored. The aim of this study was to investigate the immediate responses of NSCLC cells upon treatment with EGFR TKIs.Results: Both NSCLC cells, ie, PC9 and H1975, showed immediate enhanced adhesion-related responses as an apoptosis-countering mechanism upon first-time TKI treatment. By gene expression and pathway analysis, adhesion-related pathways were enriched in gefitinib-treated PC9 cells. Pathway inhibition by small-hairpin RNAs or small-molecule drugs revealed that within hours of EGFR TKI treatment, NSCLC cells used adhesion-related responses to combat the drugs. Importantly, we show here that the Src family inhibitor, dasatinib, dramatically inhibits

  1. Psoriatic architecture constructed by epidermal remodeling.

    Science.gov (United States)

    Iizuka, Hajime; Takahashi, Hidetoshi; Ishida-Yamamoto, Akemi

    2004-08-01

    Epidermal remodeling is the concept that epidermal architecture is determined by a simple self-organizing mechanism; epidermal hyperproliferation constructs typical psoriatic architecture. This is based on the assumption that the enlargements in both the two-dimensional proliferative compartment (basal cell layer) and three-dimensional whole epidermal volume coexist. During this process, the dermal papillae become markedly, but passively, expanded by enlargement of the proliferative compartment. This creates a considerable shrinkage force against the crowded basal cell layer, which is forced to lose adherence to the dermal extracellular matrix (ECM). This results in anoikis, a type of apoptosis characterized by cell detachment, and, consequently, a markedly diminished epidermal turnover time in psoriasis. The papillary shrinkage force also explains the fact that dermal papillary height does not exceed a certain limit. At the cessation of hyperproliferation a normalisation remodeling takes place toward normal tissue architecture. Thus the concept of epidermal remodeling explains the self-organizing mechanism of the architectural change in psoriasis, which is essentially a reversible disorder depending on epidermal hyperproliferation.

  2. A Barley ROP GTPase ACTIVATING PROTEIN Associates with Microtubules and Regulates Entry of the Barley Powdery Mildew Fungus into Leaf Epidermal Cells[C][W

    Science.gov (United States)

    Hoefle, Caroline; Huesmann, Christina; Schultheiss, Holger; Börnke, Frederik; Hensel, Götz; Kumlehn, Jochen; Hückelhoven, Ralph

    2011-01-01

    Little is known about the function of host factors involved in disease susceptibility. The barley (Hordeum vulgare) ROP (RHO of plants) G-protein RACB is required for full susceptibility of the leaf epidermis to invasion by the biotrophic fungus Blumeria graminis f. sp hordei. Stable transgenic knockdown of RACB reduced the ability of barley to accommodate haustoria of B. graminis in intact epidermal leaf cells and to form hairs on the root epidermis, suggesting that RACB is a common element of root hair outgrowth and ingrowth of haustoria in leaf epidermal cells. We further identified a barley MICROTUBULE-ASSOCIATED ROP-GTPASE ACTIVATING PROTEIN (MAGAP1) interacting with RACB in yeast and in planta. Fluorescent MAGAP1 decorated cortical microtubules and was recruited by activated RACB to the cell periphery. Under fungal attack, MAGAP1-labeled microtubules built a polarized network at sites of successful defense. By contrast, microtubules loosened where the fungus succeeded in penetration. Genetic evidence suggests a function of MAGAP1 in limiting susceptibility to penetration by B. graminis. Additionally, MAGAP1 influenced the polar organization of cortical microtubules. These results add to our understanding of how intact plant cells accommodate fungal infection structures and suggest that RACB and MAGAP1 might be antagonistic players in cytoskeleton organization for fungal entry. PMID:21685259

  3. The role of fetal epithelial tissues in the maturation/differentiation of bone marrow-derived precursors into dendritic epidermal T cells (DETC) of the mouse.

    Science.gov (United States)

    Stingl, G; Elbe, A; Paer, E; Kilgus, O; Strohal, R; Schreiber, S

    1991-01-01

    Our attempts to clarify the contribution of the thymic vs. the cutaneous microenvironment in the maturation of dendritic epidermal T cell (DETC) precursors into DETC gave diverse results. In one series of experiments, we found that i.v. injection of fetal thymocytes (containing a TCR V gamma 3-expressing subpopulation), but not of adult thymocytes (containing no TCR V gamma 3+ cells) results in the appearance of CD3/TCR V gamma 3+ dendritic epidermal cells (=DETC). In other experiments, we have obtained evidence that transplantation of day 16 fetal skin onto a Thy-1-disparate recipient results in the appearance of donor-type DETC. Our further observation that the transplanted skin contains CD45+/Thy-1+/CD3- lymphocytes, but no mature T cells, therefore implies that fetal skin can provide stimuli promoting the expression of CD3/TCR genes in immature (CD3-) DETC precursors. It remains to be seen whether both or only one of these maturational pathways are (is) followed under physiological conditions.

  4. Epidermal growth factor in the rat prostate

    DEFF Research Database (Denmark)

    Tørring, Niels; Jørgensen, P E; Poulsen, Steen Seier;

    1998-01-01

    Epidermal growth factor (EGF) induces proliferation in prostate epithelial and stromal cells in primary culture. This investigation was set up to characterize the time and spatial expression of EGF in the rat prostate.......Epidermal growth factor (EGF) induces proliferation in prostate epithelial and stromal cells in primary culture. This investigation was set up to characterize the time and spatial expression of EGF in the rat prostate....

  5. Changes in intensity of the regional Hadley cell in Indian Ocean and its impacts on surrounding regions

    Science.gov (United States)

    Freitas, Ana Carolina Vasques; Aímola, Luis; Ambrizzi, Tércio; de Oliveira, Cristiano Prestrelo

    2016-09-01

    The impacts of changes in the intensity of the regional Hadley Cell (HC) in the Indian Ocean (HCIO) on its surrounding regions are investigated during the period 1979-2013. A strengthening of the HCIO and the Indian monsoon (IM) is found during austral winter (JJA) and spring (SON) seasons. This is associated with the sea surface temperature (SST) anomalies in the Pacific and Indian Ocean. A La Niña signal started to form in JJA over the equatorial Pacific region, and in SON, it was completely developed. Significant positive SST anomalies are seen over the western Pacific and western Indian Ocean around 10°S in JJA, associated with positive temperature anomalies in the south of China, in the north of the Maritime Continent, and in the southeastern coast of Africa. In SON, they are observed over the western Pacific and eastern Indian Ocean around the equator, associated with positive temperature anomalies observed on a great part of the Maritime Continent and southeastern Atlantic Ocean. Positive rainfall anomalies are seen mainly over the south of India, south of China, Maritime Continent, and eastern coast of Australia. In SON, the connection monsoon-ENSO-Hadley is stronger, because of a series of positive feedbacks that reinforce the initial connection. SST gradients explain much of the variability in the intensity of the HCIO and, especially, of the IM. However, other factors also seem to come into play in determining the changes of the HCIO intensity, whereas the SST changes have a dominant influence on the IM.

  6. Epidermal growth factor receptor-related protein inhibits cell growth and induces apoptosis of BxPC3 pancreatic cancer cells.

    Science.gov (United States)

    Zhang, Yuxiang; Banerjee, Sanjeev; Wang, Zhi-wei; Marciniak, Dorota J; Majumdar, Adhip P N; Sarkar, Fazlul H

    2005-05-01

    Dysregulation of the epidermal growth factor receptor (EGFR) signaling network has been frequently reported in pancreatic cancer. Inhibition of EGFR was associated with antitumor effects in both in vitro and in vivo studies of pancreatic cancer. We have previously reported the isolation and characterization of an EGFR-related protein (ERRP), which seems to be a negative regulator of EGFR. In the present investigation, we tested our hypothesis whether recombinant ERRP could be an effective inhibitor of growth of BxPC3 pancreatic cancer cells. Cell growth and apoptosis were measured using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and apoptosis ELISA assay, respectively, in the presence and absence of recombinant ERRP in BxPC3 cells. To evaluate activation of EGFR and its downstream signaling events, levels of phospho-EGFR, phospho-AKT, and phospho-extracellular signal-regulated kinase (phospho-ERK) were determined by Western blot analysis. NF-kappaB activity was measured by electrophoretic mobility shift assay. Our data show, for the first time, that ERRP inhibits the growth of BxPC3 cells in a dose- and time-dependent manner. The EGF or transforming growth factor (TGF)-alpha-induced stimulation of cell growth and activation of EGFR was also inhibited by ERRP. These changes were accompanied by a concomitant attenuation of activation of mitogen-activated protein (MAP) kinases, AKT, and NF-kappaB. ERRP also induced apoptosis as evidenced by increased poly(ADP-ribose) polymerase cleavage and reduction in procaspase3. From these results, we conclude that ERRP is a potent inhibitor of growth of BxPC-3 pancreatic cancer cells, which could be due to attenuation of EGFR cellular signaling processes. We also suggest that ERRP could be a potential therapeutic agent for pancreatic cancer.

  7. Research Progress of Epidermal Growth Factor Receptor and Molecular-Targeted Therapy in Treatment of Non-Small Cell Lung Cancer

    Institute of Scientific and Technical Information of China (English)

    Li Xiaoyou; Feng Jifeng

    2014-01-01

    Molecular target therapy has become a new approach in the treatment of advanced non-small cell lung cancer (NSCLC). The sensitivity of lung cancer to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) has been found to be associated with gene mutationss in the tyrosine kinase domain of RGFR. However, not all EGFR gene mutationss are sensitive to EGFR-TKIs. The review was conducted to study the research progress of EGFR mutations and the sensitivity to EGFR-TKIs and the mechanism of resistance of molecular target therapy in NSCLC.

  8. Research Progress on Resistance Mechanisms of Epidermal Growth Factor Receptor 
Tyrosine Kinase Inhibitors in Non-small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Yuan LI

    2012-02-01

    Full Text Available With a greater understanding of tumor biology, novel molecular-targeted strategies that block cancer progression pathways have been evaluated as a new therapeutic approach for treating non-small cell lung cancer (NSCLC. Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs, such as gefitinib and erlotinib, show favorable response to EGFR mutant lung cancer in some populations of NSCLC patients. However, the efficacy of EGFR-TKIs is limited by either primary (de novo or acquired resistance after therapy. This review will focus on recently identified mechanisms of primary and acquired resistance to EGFR TKIs and strategies currently being employed to overcome resistance.

  9. Research Progress of Epidermal Growth Factor Receptor and Molecular-Targeted Therapy in Treatment of Non-Small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Xiaoyou Li

    2014-03-01

    Full Text Available Molecular target therapy has become a new approach in the treatment of advanced non-small cell lung cancer (NSCLC. The sensitivity of lung cancer to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs has been found to be associated with gene mutationss in the tyrosine kinase domain of RGFR. However, not all EGFR gene mutationss are sensitive to EGFR-TKIs. The review was conducted to study the research progress of EGFR mutations and the sensitivity to EGFR-TKIs and the mechanism of resistance of molecular target therapy in NSCLC.

  10. Verrucous epidermal nevus

    OpenAIRE

    Kim, Randie; Marmon, Shoshana; Kaplan, Jennifer; Kamino, Hideko; Pomeranz, Miriam Keltz

    2013-01-01

    A 64-year-old man presented with a three-year history of an enlarging, pruritic, linear, verrucous plaque on his left lower extremity. Histopathologic examination was consistent with a verrucous epidermal nevus, which is a benign epidermal hamartoma, most commonly observed in the pediatric population. Verrucous epidermal nevi are often refractory to treatment and have high rates of recurrences, causing them to be therapeutic challenges. We review the treatment modalities reported to be effect...

  11. Release of infectious cells from epidermal ulcers in Ichthyophonus sp.–infected Pacific Herring (Clupea pallasii): Evidence for multiple mechanisms of transmission

    Science.gov (United States)

    Hershberger, Paul K.; Gregg, Jacob L.; Kocan, R.M.

    2010-01-01

    A common clinical sign of ichthyophoniasis in herring and trout is “sandpaper” skin, a roughening of the epidermis characterized by the appearance of small papules, followed by ulceration and sloughing of the epithelium; early investigators hypothesized that these ulcers might be a means of transmitting the parasite, Ichthyophonus sp., without the necessity of ingesting an infected host. We examined the cells associated with the epidermal lesions and confirmed that they were viable Ichthyophonus sp. cells that were readily released from the skin into the mucous layer and ultimately into the aquatic environment. The released cells were infectious when injected into the body cavity of specific-pathogen-free herring. Our hypothesis is that different mechanisms of transmission occur in carnivorous and planktivorous hosts: Planktonic feeders become infected by ingestion of ulcer-derived cells, while carnivores become infected by ingestion of whole infected fish.

  12. Construction of Epidermal Growth Factor Receptor Peptide Magnetic Nanovesicles with Lipid Bilayers for Enhanced Capture of Liver Cancer Circulating Tumor Cells.

    Science.gov (United States)

    Ding, Jian; Wang, Kai; Tang, Wen-Jie; Li, Dan; Wei, You-Zhen; Lu, Ying; Li, Zong-Hai; Liang, Xiao-Fei

    2016-09-20

    Highly effective targeted tumor recognition via vectors is crucial for cancer detection. In contrast to antibodies and proteins, peptides are direct targeting ligands with a low molecular weight. In the present study, a peptide magnetic nanovector platform containing a lipid bilayer was designed using a peptide amphiphile (PA) as a skeleton material in a controlled manner without surface modification. Fluorescein isothiocyanate-labeled epidermal growth factor receptor (EGFR) peptide nanoparticles (NPs) could specifically bind to EGFR-positive liver tumor cells. EGFR peptide magnetic vesicles (EPMVs) could efficiently recognize and separate hepatoma carcinoma cells from cell solutions and treated blood samples (ratio of magnetic EPMVs versus anti-EpCAM NPs: 3.5 ± 0.29). Analysis of the circulating tumor cell (CTC) count in blood samples from 32 patients with liver cancer showed that EPMVs could be effectively applied for CTC capture. Thus, this nanoscale, targeted cargo-packaging technology may be useful for designing cancer diagnostic systems.

  13. Induced accessibility and inaccessibility to ¤Blumeria graminis¤ f.sp. ¤hordei¤ in barley epidermal cells attacked by a compatible isolate

    DEFF Research Database (Denmark)

    Lyngkjær, M.F.; Carver, T.L.W.

    1999-01-01

    inoculation, approximately 67% of penetration attempts successfully formed haustoria. However, in epidermal cells successfully penetrated by the inducer, almost all attacks by the challenger succeeded (> 90%). Thus, accessibility was induced in these cells. In some cases, accessibility was also induced....... The size of papillae formed in challenged cells could not account for induced inaccessibility. However, induced accessibility appeared to be associated with suppression of localized autofluorescent host cell responses to challenger attack, whereas inaccessibility was associated with increased frequency......First leaves of the barley line Riso-5678S were subjected to a double inoculation procedure ('inducer' followed by 'challenger') with conidia of a genetically compatible isolate of Blumeria graminis (DC.) Speer (Syn. Erysiphe graminis DC.). In control leaves, attacked by appressoria from a single...

  14. Cooperation of tyrosine kinase receptor TrkB and epidermal growth factor receptor signaling enhances migration and dispersal of lung tumor cells.

    Directory of Open Access Journals (Sweden)

    Rudolf Götz

    Full Text Available TrkB mediates the effects of brain-derived neurotrophic factor (BDNF in neuronal and nonnneuronal cells. Based on recent reports that TrkB can also be transactivated through epidermal growth-factor receptor (EGFR signaling and thus regulates migration of early neurons, we investigated the role of TrkB in migration of lung tumor cells. Early metastasis remains a major challenge in the clinical management of non-small cell lung cancer (NSCLC. TrkB receptor signaling is associated with metastasis and poor patient prognosis in NSCLC. Expression of this receptor in A549 cells and in another adenocarcinoma cell line, NCI-H441, promoted enhanced migratory capacity in wound healing assays in the presence of the TrkB ligand BDNF. Furthermore, TrkB expression in A549 cells potentiated the stimulatory effect of EGF in wound healing and in Boyden chamber migration experiments. Consistent with a potential loss of cell polarity upon TrkB expression, cell dispersal and de-clustering was induced in A549 cells independently of exogeneous BDNF. Morphological transformation involved extensive cytoskeletal changes, reduced E-cadherin expression and suppression of E-cadherin expression on the cell surface in TrkB expressing tumor cells. This function depended on MEK and Akt kinase activity but was independent of Src. These data indicate that TrkB expression in lung adenoma cells is an early step in tumor cell dissemination, and thus could represent a target for therapy development.

  15. Size-dependent effects of tungsten carbide-cobalt particles on oxygen radical production and activation of cell signaling pathways in murine epidermal cells.

    Science.gov (United States)

    Ding, M; Kisin, E R; Zhao, J; Bowman, L; Lu, Y; Jiang, B; Leonard, S; Vallyathan, V; Castranova, V; Murray, A R; Fadeel, B; Shvedova, A A

    2009-12-15

    Hard metal or cemented carbide consists of a mixture of tungsten carbide (WC) (85%) and metallic cobalt (Co) (5-15%). WC-Co is considered to be potentially carcinogenic to humans. However, no comparison of the adverse effects of nano-sized WC-Co particles is available to date. In the present study, we compared the ability of nano- and fine-sized WC-Co particles to form free radicals and propensity to activate the transcription factors, AP-1 and NF-kappaB, along with stimulation of mitogen-activated protein kinase (MAPK) signaling pathways in a mouse epidermal cell line (JB6 P(+)). Our results demonstrated that nano-WC-Co generated a higher level of hydroxyl radicals, induced greater oxidative stress, as evidenced by a decrease of GSH levels, and caused faster JB6 P(+) cell growth/proliferation than observed after exposure of cells to fine WC-Co. In addition, nano-WC-Co activated AP-1 and NF-kappaB more efficiently in JB6(+/+) cells as compared to fine WC-Co. Experiments using AP-1-luciferase reporter transgenic mice confirmed the activation of AP-1 by nano-WC-Co. Nano- and fine-sized WC-Co particles also stimulated MAPKs, including ERKs, p38, and JNKs with significantly higher potency of nano-WC-Co. Finally, co-incubation of the JB6(+/+) cells with N-acetyl-cysteine decreased AP-1 activation and phosphorylation of ERKs, p38 kinase, and JNKs, thus suggesting that oxidative stress is involved in WC-Co-induced toxicity and AP-1 activation.

  16. Expression of biomarkers (p53, transforming growth factor alpha, epidermal growth factor receptor, c-erbB-2/neu and the proliferative cell nuclear antigen) in oropharyngeal squamous cell carcinomas

    OpenAIRE

    1999-01-01

    Using immunohistochemistry, expression of p53, transforming growth factor-alpha (TGF-α), epidermal growth factor receptor (EGFR), c-erbB-2/neu and proliferating cell nuclear antigen (PCNA) was examined in 26 fresh frozen tissue specimens of oropharyngeal squamous cell carcinomas (SCCs). p53 gene mutations were examined by polymerase chain reaction (PCR)/DNA sequencing methods in 22 carcinomas. The findings were examined for correlations with patients’ clinicopathological parameters. Expressio...

  17. Novel Antioxidant Tripeptide "ACQ" Can Prevent UV-Induced Cell Death and Preserve the Number of Epidermal Stem Cells.

    Science.gov (United States)

    Choi, Hye-Ryung; Shin, Jung-Won; Na, Jung-Im; Nam, Kyung-Mi; Lee, Hyun-Sun; Park, Kyoung-Chan

    2015-01-01

    We found that tripeptide "ACQ: alanine-cysteine-glutamine" has significant DPPH scavenging activity compared to that of glutathione. Antioxidant effects of ACQ were tested in in vitro and in vivo models. When treated with H2O2, mock treated fibroblasts and keratinocytes showed strong staining by H2DCFA. But, ACQ showed good protective effects against hydrogen peroxide treatment. When mice were fed for 2 or 4 weeks, similar protective effects were observed. In the control group, epidermis was severely damaged by UV irradiation and apoptotic keratinocytes were observed. There were also numerous TUNEL positive cells. But in the ACQ group, epidermis became thicker and there was no sign of severe damage. Interestingly, the number of p63 cells was also higher in ACQ fed mice. To confirm the stem cell rescuing effects of ACQ, three-dimensional skin samples were constructed. Results showed that ACQ increased the expression of integrin α6 and the number of p63 positive cells. These findings showed that ACQ has good antioxidant activity and may increase stem cell activities by the regulation of integrin α6.

  18. Early radiographic response to epidermal growth factor receptor-tyrosine kinase inhibitor in non-small cell lung cancer patients with epidermal growth factor receptor mutations: A prospective study

    Directory of Open Access Journals (Sweden)

    John WC Chang

    2015-06-01

    Full Text Available Background: The time schedules for response evaluation of epidermal growth factor receptor-tyrosine kinase Inhibitor (EGFR-TKI in non-small cell lung cancer (NSCLC patients are still ill-defined. Methods: Stage IIIB/IV patients with histologically proven NSCLC were enrolled in this study if the tumor cells bore EGFR mutations other than T790M. Eligible patients were treated with either 250 mg of gefitinib or 150 mg of erlotinib once daily. The early response rate [computed tomography (CT scan on Day 14], definitive response rate determined on Day 56, progression-free survival (PFS, overall survival (OS, and toxicity profile were assessed prospectively. Results: Thirty-nine patients were enrolled in this study. A total of 29 patients (29/39, 74.4% achieved partial response (PR. Twenty-one patients (21/39, 53.8% had early radiological response on Day 14. The early radiological response rate in patients with PR was 72.4% (21/29. Only eight patients without a PR on early CT still ended with PR. Among the 29 patients with PR, the PFS (8.1 months and OS (18.3 months of the 21 patients with early CT response were shorter than those of the 8 patients without early CT response (11.9 and 24.0 months for PFS and OS, respectively. But the survival differences were statistically non-significant. Conclusions: A very high percentage (72.4%, 21/29 of NSCLC patients with EGFR mutations with PR demonstrates early radiological response to EGFR-TKIs, which would advocate early radiological examination for EGFR-TKI therapy in NSCLC patients.

  19. Genetics Home Reference: epidermal nevus

    Science.gov (United States)

    ... thicker and darker and develop a wart-like (verrucous) appearance. Often, keratinocytic epidermal nevi follow a pattern ... are also known as linear epidermal nevi or verrucous epidermal nevi, based on characteristics of their appearance. ...

  20. Multiple papillomavirus-associated epidermal hamartomas and squamous cell carcinomas in situ in a dog following chronic treatment with prednisone and cyclosporine.

    Science.gov (United States)

    Callan, Mary Beth; Preziosi, Diane; Mauldin, Elizabeth

    2005-10-01

    A 4-year-old, spayed female toy fox terrier developed multiple epidermal hamartomas and squamous cell carcinomas in situ following chronic immunosuppressive therapy with prednisone and cyclosporine for management of an immune-mediated nonregenerative anaemia. Immunohistochemical staining was positive for papillomavirus antigen within both benign (n = 19) and malignant (n = 8) cutaneous lesions that developed during a 3-year period of observation, with positive staining most often seen in keratinocytes in the granular cell layer. Treatment of the papillomavirus infection with interferon-alpha was discontinued after 2 weeks because of diarrhoea and a further increase in liver enzymes. The cutaneous lesions of this dog persisted and new lesions developed during the year following discontinuation of both cyclosporine and prednisone. This is the first reported case of papillomavirus-associated squamous cell carcinoma in situ developing in a dog following chronic administration of cyclosporine and prednisone.

  1. Usefulness of circulating free DNA for monitoring epidermal growth factor receptor mutations in advanced non-small cell lung cancer patients: a case report

    Science.gov (United States)

    Gonzalez-Cao, Maria; Ramirez, Santiago Viteri; Ariza, Nuria Jordana; Balada, Ariadna; Garzón, Mónica; Teixidó, Cristina; Karachaliou, Niki; Morales-Espinosa, Daniela; Molina-Vila, Miguel Ángel; Rosell, Rafael

    2016-01-01

    Genomic analysis of circulating tumor DNA (ctDNA) released from cancer cells into the bloodstream has been proposed as a useful method to capture dynamic changes during the course of the disease. In particular, the ability to monitor epidermal growth factor receptor (EGFR) mutation status in cell-free circulating DNA (cfDNA) isolated from advanced non-small cell lung cancer (NSCLC) patients EGFR can help to the correct management of the disease and overcome the challenges associated with tumor heterogeneity and insufficient biopsied material to perform key molecular diagnosis. Here, we report a case of long term monitorization of EGFR mutation status in cfDNA from peripheral blood in an NSCLC patient in, with excellent correlation with clinical evolution. PMID:27826535

  2. Lipid raft localization of epidermal growth factor receptor alters matrix metalloproteinase-1 expression in SiHa cells via the MAPK/ERK signaling pathway

    Science.gov (United States)

    Zhang, Zongfeng; Wang, Lina; Du, Juan; Li, Yuanbo; Yang, Huilun; Li, Chenxi; Li, Hui; Hu, Haiyang

    2016-01-01

    Matrix metalloproteinase-1 (MMP-1) has been identified as an important participant in tumor invasion, metastasis and angiogenesis. The purpose of the present study was to investigate the effects of epidermal growth factor receptor (EGFR) localization to lipid rafts on signaling pathways involved in the regulation of MMP-1 expression in SiHa cells, a cervical cancer cell line. EGFR activation by EGF specifically induced MMP-1 expression at both the messenger RNA and protein levels. Additionally, it was observed that EGFR localized to lipid rafts, and that the redistribution of EGFR induced by lipid raft disruption strengthened EGF-induced MMP-1 expression. MMP-1 induction was blocked by the mitogen-activated protein kinase (MAPK) kinase inhibitors PD98059 and U0126. Our results suggested that lipid rafts provide a platform to inhibit EGFR regulation of MMP-1 in SiHa cells through the MAPK/extracellular signal-regulated kinase signaling pathway.

  3. Templated green synthesis of plasmonic silver nanoparticles in onion epidermal cells suitable for surface-enhanced Raman and hyper-Raman scattering

    Directory of Open Access Journals (Sweden)

    Marta Espina Palanco

    2016-06-01

    Full Text Available We report fast and simple green synthesis of plasmonic silver nanoparticles in the epidermal cells of onions after incubation with AgNO3 solution. The biological environment supports the generation of silver nanostructures in two ways. The plant tissue delivers reducing chemicals for the initial formation of small silver clusters and their following conversion to plasmonic particles. Additionally, the natural morphological structures of the onion layers, in particular the extracellular matrix provides a biological template for the growth of plasmonic nanostructures. This is indicated by red glowing images of extracellular spaces in dark field microscopy of onion layers a few hours after AgNO3 exposure due to the formation of silver nanoparticles. Silver nanostructures generated in the extracellular space of onion layers and within the epidermal cell walls can serve as enhancing plasmonic structures for one- and two-photon-excited spectroscopy such as surface enhanced Raman scattering (SERS and surface enhanced hyper-Raman scattering (SEHRS. Our studies demonstrate a templated green preparation of enhancing plasmonic nanoparticles and suggest a new route to deliver silver nanoparticles as basic building blocks of plasmonic nanosensors to plants by the uptake of solutions of metal salts.

  4. Crinkly4 receptor-like kinase is required to maintain the interlocking of the palea and lemma, and fertility in rice, by promoting epidermal cell differentiation.

    Science.gov (United States)

    Pu, Cui-Xia; Ma, Yun; Wang, Jiao; Zhang, Yong-Cun; Jiao, Xue-Wen; Hu, Yu-Hong; Wang, Ling-Ling; Zhu, Zheng-Ge; Sun, Daye; Sun, Ying

    2012-06-01

    The palea and lemma are unique organs in grass plants that form a protective barrier around the floral organs and developing kernel. The interlocking of the palea and lemma is critical for maintaining fertility and seed yield in rice; however, the molecules that control the interlocking structure remain largely unknown. Here, we showed that when OsCR4 mRNA expression was knocked down in rice by RNA interference, the palea and lemma separated at later spikelet stages and gradually turned brown after heading, resulting in the severe interruption of pistil pollination and damage to the development of embryo and endosperm, with defects in aleurone. The irregular architecture of the palea and lemma was caused by tumour-like cell growth in the outer epidermis and wart-like cell masses in the inner epidermis. These abnormal cells showed discontinuous cuticles and uneven cell walls, leading to organ self-fusion that distorted the interlocking structures. Additionally, the faster leakage of chlorophyll, reduced silica content and elevated accumulation of anthocyanin in the palea and lemma indicated a lesion in the protective barrier, which also impaired seed quality. OsCR4 is an active receptor-like kinase associated with the membrane fraction. An analysis of promoter::GUS reporter plants showed that OsCR4 is specifically expressed in the epidermal cells of paleas and lemmas. Together, these results suggest that OsCR4 plays an essential role in maintaining the interlocking of the palea and lemma by promoting epidermal cell differentiation. © 2012 YING SUN. The Plant Journal © 2012 Blackwell Publishing Ltd.

  5. The response to epidermal growth factor of human maxillary tumor cells in terms of tumor growth, invasion and expression of proteinase inhibitors.

    Science.gov (United States)

    Mizoguchi, H; Komiyama, S; Matsui, K; Hamanaka, R; Ono, M; Kiue, A; Kobayashi, M; Shimizu, N; Welgus, H G; Kuwano, M

    1991-11-11

    Three cancer cell lines, IMC-2, IMC-3 and IMC-4, were established from a single tumor of a patient with maxillary cancer. We examined responses to epidermal growth factor (EGF) of these 3 cell lines with regard to cell growth and tumor invasion. The growth rate of IMC-2 in nude mice was markedly faster than that of the IMC-3 and IMC-4 cell lines. Assay for invasion through fibrin gels showed significantly enhanced invasive capacity of IMC-2 cells in response to EGF, but no change for IMC-3 and IMC-4 cells. We examined response to EGF of IMC-2 cells with regard to expression of a growth-related oncogene (c-fos), proteinases and their inhibitors. Expression of c-fos was transiently increased in IMC-2 cells at rates comparable to those seen in the 2 other lines in the presence of EGF. There was no apparent effect of EGF on the expression of urokinase-type plasminogen activator and 72-kDa type-IV collagenase in IMC-2 cells. In contrast, EGF specifically enhanced the expression of plasminogen activator inhibitor-I (PAI-I) and tissue inhibitor of metalloproteinases-I (TIMP-I) in IMC-2 cells. Our data suggest that proteinase inhibitors or other related factors may play an important role in tumor growth and invasion in response to EGF.

  6. Filaggrin and the great epidermal barrier grief.

    Science.gov (United States)

    McGrath, John A

    2008-05-01

    One of the principal functions of human skin is to form an effective mechanical barrier against the external environment. This involves the maturation and death of epidermal keratinocytes as well as the assembly of a complex network of differentially and spatially expressed proteins, glycoproteins and lipids into the keratinocyte cell membrane and surrounding extracellular space. In 2006, the key role of the granular cell layer protein filaggrin (filament-aggregating protein) in maintaining the skin barrier was determined with the identification of loss-of-function mutations in the profilaggrin gene (FLG). These mutations have been shown to be the cause of ichthyosis vulgaris and a major risk factor for the development of atopic dermatitis, asthma associated with atopic dermatitis as well as systemic allergies. Mutations in the FLG gene are extremely common, occurring in approximately 9% of individuals from European populations. The remarkable discovery of these widespread mutations is expected to have a major impact on the classification and management of many patients with ichthyosis and atopic disease. It is also hoped that the genetic discovery of FLG mutations will lead to the future development of more specific, non-immunosuppressive treatments capable of restoring effective skin barrier function and alleviating or preventing disease in susceptible individuals.

  7. Antacid Use and De Novo Brain Metastases in Patients with Epidermal Growth Factor Receptor-Mutant Non-Small Cell Lung Cancer Who Were Treated Using First-Line First-Generation Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors.

    Directory of Open Access Journals (Sweden)

    Yu-Mu Chen

    Full Text Available Antacid treatments decrease the serum concentrations of first-generation epidermal growth factor receptor (EGFR-tyrosine kinase inhibitors (TKIs, although it is unknown whether antacids affect clinical outcomes. As cerebrospinal fluid concentrations of TKIs are much lower than serum concentrations, we hypothesized that this drug-drug interaction might affect the prognosis of patients with de novo brain metastases.This retrospective study evaluated 269 patients with EGFR-mutant non-small cell lung cancer (NSCLC who had been diagnosed between December 2010 and December 2013, and had been treated using first-line first-generation EGFR-TKIs. Among these patients, we identified patients who concurrently used H2 receptor antagonists (H2RAs and proton pump inhibitors (PPIs as antacids. Patients who exhibited >30% overlap between the use of TKIs and antacids were considered antacid users.Fifty-seven patients (57/269, 21.2% were antacid users, and antacid use did not significantly affect progression-free survival (PFS; no antacids: 11.2 months, H2RAs: 9.4 months, PPIs: 6.7 months; p = 0.234. However, antacid use significantly reduced overall survival (OS; no antacids: 25.0 months, H2RAs: 15.5 months, PPIs: 11.3 months; p = 0.002. Antacid use did not affect PFS for various metastasis sites, although antacid users with de novo brain metastases exhibited significantly shorter OS, compared to non-users (11.8 vs. 16.3 months, respectively; p = 0.041. Antacid use did not significantly affect OS in patients with bone, liver, or pleural metastases.Antacid use reduced OS among patients with EGFR-mutant NSCLC who were treated using first-line first-generation EGFR-TKIs, and especially among patients with de novo brain metastases.

  8. Targeting the epidermal growth factor receptor in non-small cell lung cancer cells: the effect of combining RNA interference with tyrosine kinase inhibitors or cetuximab

    Directory of Open Access Journals (Sweden)

    Chen Gang

    2012-03-01

    Full Text Available Abstract Background The epidermal growth factor receptor (EGFR is a validated therapeutic target in non-small cell lung cancer (NSCLC. However, current single agent receptor targeting does not achieve a maximal therapeutic effect, and some mutations confer resistance to current available agents. In the current study we have examined, in different NSCLC cell lines, the combined effect of RNA interference targeting the EGFR mRNA, and inactivation of EGFR signaling using different receptor tyrosine kinase inhibitors (TKIs or a monoclonal antibody cetuximab. Methods NSCLC cells (cell lines HCC827, H292, H358, H1650, and H1975 were transfected with EGFR siRNA and/or treated with the TKIs gefitinib, erlotinib, and afatinib, and/or with the monoclonal antibody cetuximab. The reduction of EGFR mRNA expression was measured by real-time quantitative RT-PCR. The down-regulation of EGFR protein expression was measured by western blot, and the proliferation, viability, caspase3/7 activity, and apoptotic morphology were monitored by spectrophotometry, fluorimetry, and fluorescence microscopy. The combined effect of EGFR siRNA and different drugs was evaluated using a combination index. Results EGFR-specific siRNA strongly inhibited EGFR protein expression almost equally in all cell lines and inhibited cell growth and induced cell apoptosis in all NSCLC cell lines studied, albeit with a different magnitude. The effects on growth obtained with siRNA was strikingly different from the effects obtained with TKIs. The effects of siRNA probably correlate with the overall oncogenic significance of the receptor, which is only partly inhibited by the TKIs. The cells which showed weak response to TKIs, such as the H1975 cell line containing the T790M resistance mutation, were found to be responsive to siRNA knockdown of EGFR, as were cell lines with downstream TKI resistance mutations. The cell line HCC827, harboring an exon 19 deletion mutation, was more than 10-fold

  9. Toxic epidermal necrolysis related to AP (pemetrexed plus cisplatin) and gefitinib combination therapy in a patient with metastatic non-small cell lung cancer

    Institute of Scientific and Technical Information of China (English)

    Ji-Jie Huang; Shu-Xiang Ma; Xue Hou; Zhao Wang; Yin-Duo Zeng; Tao Qin; Xiao-Xiao Dinglin; Li-Kun Chen

    2015-01-01

    Toxic epidermal necrolysis (TEN) is a rare acute life-threatening mucocutaneous disorder that is mostly drug-related (80%-95%). It is clinical y characterized as a widespread sloughing of the skin and mucosa. AP regimen (pemetrexed plus cisplatin) has been the preferred first-line chemotherapy for metastatic non-squamous non-small cell lung cancer (NSCLC). Gefitinib, a small-molecule epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), has already been recommended as a first-line treatment in EGFR-mutant metastatic NSCLC. We report rare presentation of TEN involving adverse effects of AP and gefitinib combination treatment in a 42-year-old woman diagnosed with metastatic NSCLC harboring an EGFR mutation. On the 21st day after administration of the first cycle of AP regimen and the 8th day after the initiation of gefitinib treatment, she developed an acne-like rash, oral ulcer, and conjunctivitis, which later became blisters and ultimately denuded. The characteristic clinical courses were decisive for the diagnosis of TEN. Treatment with systemic steroids and immunoglobulin as well as supportive treatment led to an improvement of her general condition and a remarkable recovery.

  10. EGF–FGF{sub 2} stimulates the proliferation and improves the neuronal commitment of mouse epidermal neural crest stem cells (EPI-NCSCs)

    Energy Technology Data Exchange (ETDEWEB)

    Bressan, Raul Bardini; Melo, Fernanda Rosene; Almeida, Patricia Alves; Bittencourt, Denise Avani; Visoni, Silvia; Jeremias, Talita Silva [Departamento de Biologia Celular, Embriologia e Genética, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário – Trindade, 88040-900 Florianópolis SC (Brazil); Costa, Ana Paula; Leal, Rodrigo Bainy [Departamento de Bioquímica, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário – Trindade, 88040-900 Florianópolis SC (Brazil); Trentin, Andrea Gonçalves, E-mail: andrea.trentin@ufsc.br [Departamento de Biologia Celular, Embriologia e Genética, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Universitário – Trindade, 88040-900 Florianópolis SC (Brazil)

    2014-09-10

    Epidermal neural crest stem cells (EPI-NCSCs), which reside in the bulge of hair follicles, are attractive candidates for several applications in cell therapy, drug screening and tissue engineering. As suggested remnants of the embryonic neural crest (NC) in an adult location, EPI-NCSCs are able to generate a wide variety of cell types and are readily accessible by a minimally invasive procedure. Since the combination of epidermal growth factor (EGF) and fibroblast growth factor type 2 (FGF{sub 2}) is mitogenic and promotes the neuronal commitment of various stem cell populations, we examined its effects in the proliferation and neuronal potential of mouse EPI-NCSCs. By using a recognized culture protocol of bulge whiskers follicles, we were able to isolate a population of EPI-NCSCs, characterized by the migratory potential, cell morphology and expression of phenotypic markers of NC cells. EPI-NCSCs expressed neuronal, glial and smooth muscle markers and exhibited the NC-like fibroblastic morphology. The treatment with the combination EGF and FGF{sub 2}, however, increased their proliferation rate and promoted the acquisition of a neuronal-like morphology accompanied by reorganization of neural cytoskeletal proteins βIII-tubulin and nestin, as well as upregulation of the pan neuronal marker βIII-tubulin and down regulation of the undifferentiated NC, glial and smooth muscle cell markers. Moreover, the treatment enhanced the response of EPI-NCSCs to neurogenic stimulation, as evidenced by induction of GAP43, and increased expression of Mash-1 in neuron-like cell, both neuronal-specific proteins. Together, the results suggest that the combination of EGF–FGF2 stimulates the proliferation and improves the neuronal potential of EPI-NCSCs similarly to embryonic NC cells, ES cells and neural progenitor/stem cells of the central nervous system and highlights the advantage of using EGF–FGF{sub 2} in neuronal differentiation protocols. - Highlights: • EPI

  11. Tratamento hipofracionado de radioterapia em felinos portadores de carcinoma epidermóide facial Hypofractionated radiation therapy for the treatment of feline facial squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    S.C.S. Cunha

    2010-10-01

    Full Text Available Avaliou-se a eficácia do protocolo radioterápico hipofracionado no tratamento de felinos portadores de carcinoma epidermóide facial. Um protocolo hipofracionado de radioterapia foi aplicado em cinco gatos portadores de um ou mais carcinomas epidermóides faciais, em um total de 10 lesões neoplásicas, confirmadas por meio de análise histológica. Duas lesões foram classificadas como T1, quatro como T2, duas como T3 e duas como T4. Os animais foram submetidos a quatro frações radioterápicas de 7,6 a 10gy, com intervalo de uma semana entre elas, utilizando-se um acelerador linear com feixe de elétrons. O acompanhamento dos animais foi realizado semanalmente durante o tratamento e aos 30 e 60 dias após o término da radioterapia. Neste estudo, 40% das lesões resultaram em remissão completa, 40% em remissão parcial e 20% não apresentaram resposta ao tratamento. A taxa de resposta encontrada nessa pesquisa foi baixa, porém o protocolo de hipofracionamento radioterápico foi seguro para gatos com carcinoma epidermóide facial e resultou em efeitos colaterais leves/moderadosThe efficacy of hypofractionated radiation protocol for feline facial squamous cell carcinoma was evaluated. Hypofractionated radiation therapy was applied to five cats showing single or multiple facial squamous cell carcinomas, in a total of ten histologically confirmed neoplastic lesions. Of the lesions, two were staged as T1, four as T2, two as T3, and two as T4. The animals were submitted to four radiation fractions from 7.6 to 10 grays each, with one week intervals. The equipment was a linear accelerator with electrons beam. The cats were evaluated weekly during the treatment and 30 and 60 days after the end of the radiation therapy. In this study, 40% of the lesions had complete remission, 40% partial remission, and 20% did not respond to the treatment. Response rates were lower as compared to other protocols previously used. However, hypofractionated radiation

  12. Tissue kallikrein induces SH-SY5Y cell proliferation via epidermal growth factor receptor and extracellular signal-regulated kinase1/2 pathway

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Zhengyu [Department of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200040 (China); Department of Neurology, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 200437 (China); Yang, Qi; Cui, Mei; Liu, Yanping [Department of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200040 (China); Wang, Tao; Zhao, Hong [Department of Neurology, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 200437 (China); Dong, Qiang, E-mail: qiang_dong163@163.com [Department of Neurology, Huashan Hospital, State Key Laboratory of Medical Neurobiology, Fudan University, Shanghai 200040 (China)

    2014-03-28

    Highlights: • TK promotes EGFR phosphorylation in SH-SY5Y cells. • TK activates ERK1/2 and p38 phosphorylation in SH-SY5Y cells. • TK mediates SH-SY5Y cell proliferation via EGFR and ERK1/2 pathway. - Abstract: Tissue kallikrein (TK) is well known to take most of its biological functions through bradykinin receptors. In the present study, we found a novel signaling pathway mediated by TK through epidermal growth factor receptor (EGFR) in human SH-SY5Y cells. We discovered that TK facilitated the activation of EGFR, extracellular signal-regulated kinase (ERK) 1/2 and p38 cascade. Interestingly, not p38 but ERK1/2 phosphorylation was severely compromised in cells depleted of EGFR. Nevertheless, impairment of signaling of ERK1/2 seemed not to be restricted to EGFR phosphorylation. We also observed that TK stimulation could induce SH-SY5Y cell proliferation, which was reduced by EGFR down-regulation or ERK1/2 inhibitor. Overall, our findings provided convincing evidence that TK could mediate cell proliferation via EGFR and ERK1/2 pathway in vitro.

  13. Comparative SAXS and DSC study on stratum corneum structural organization in an epidermal cell culture model (ROC): impact of cultivation time.

    Science.gov (United States)

    Kuntsche, Judith; Herre, Angela; Fahr, Alfred; Funari, Sérgio S; Garidel, Patrick

    2013-12-18

    Cell cultured skin equivalents present an alternative for dermatological in vitro evaluations of drugs and excipients as they provide the advantage of availability, lower variability and higher assay robustness compared to native skin. For penetration/permeation studies, an adequate stratum corneum barrier similar to that of human stratum corneum is, however, a prerequisite. In this study, the stratum corneum lipid organization in an epidermal cell culture model based on rat epidermal keratinocytes (REK organotypic culture, ROC) was investigated by small-angle X-ray scattering (SAXS) in dependence on ROC cultivation time and in comparison to native human and rat stratum cornea. In addition, the thermal phase behavior was studied by differential scanning calorimetry (DSC) and barrier properties were checked by measurements of the permeability of tritiated water. The development of the barrier of ROC SC obtained at different cultivation times (7, 14 and 21 days at the air-liquid interface) was connected with an increase in structural order of the SC lipids in SAXS measurements: Already cultivation for 14 days at the air-liquid interface resulted overall in a competent SC permeability barrier and SC lipid organization. Cultivation for 21 days resulted in further minor changes in the structural organization of ROC SC. The SAXS patterns of ROC SC had overall large similarities with that of human SC and point to the presence of a long periodicity phase with a repeat distance of about 122Å, e.g. slightly smaller than that determined for human SC in the present study (127Å). Moreover, SAXS results also indicate the presence of covalently bound ceramides, which are crucial for a proper SC barrier, although the corresponding thermal transitions were not clearly detectable by DSC. Due to the competent SC barrier properties and high structural and organizational similarity to that of native human SC, ROC presents a promising alternative for in vitro studies, particularly as

  14. Multiple transcription factor codes activate epidermal wound-response genes in Drosophila.

    Science.gov (United States)

    Pearson, Joseph C; Juarez, Michelle T; Kim, Myungjin; Drivenes, Øyvind; McGinnis, William

    2009-02-17

    Wounds in Drosophila and mouse embryos induce similar genetic pathways to repair epidermal barriers. However, the transcription factors that transduce wound signals to repair epidermal barriers are largely unknown. We characterize the transcriptional regulatory enhancers of 4 genes-Ddc, ple, msn, and kkv-that are rapidly activated in epidermal cells surrounding wounds in late Drosophila embryos and early larvae. These epidermal wound enhancers all contain evolutionarily conserved sequences matching binding sites for JUN/FOS and GRH transcription factors, but vary widely in trans- and cis-requirements for these inputs and their binding sites. We propose that the combination of GRH and FOS is part of an ancient wound-response pathway still used in vertebrates and invertebrates, but that other mechanisms have evolved that result in similar transcriptional output. A common, but largely untested assumption of bioinformatic analyses of gene regulatory networks is that transcription units activated in the same spatial and temporal patterns will require the same cis-regulatory codes. Our results indicate that this is an overly simplistic view.

  15. Transcriptional profiling of epidermal differentiation.

    Science.gov (United States)

    Radoja, Nada; Gazel, Alix; Banno, Tomohiro; Yano, Shoichiro; Blumenberg, Miroslav

    2006-10-03

    In epidermal differentiation basal keratinocytes detach from the basement membrane, stop proliferating, and express a new set of structural proteins and enzymes, which results in an impermeable protein/lipid barrier that protects us. To define the transcriptional changes essential for this process, we purified large quantities of basal and suprabasal cells from human epidermis, using the expression of beta4 integrin as the discriminating factor. The expected expression differences in cytoskeletal, cell cycle, and adhesion genes confirmed the effective separation of the cell populations. Using DNA microarray chips, we comprehensively identify the differences in genes expressed in basal and differentiating layers of the epidermis, including the ECM components produced by the basal cells, the proteases in both the basal and suprabasal cells, and the lipid and steroid metabolism enzymes in suprabasal cells responsible for the permeability barrier. We identified the signaling pathways specific for the two populations and found two previously unknown paracrine and one juxtacrine signaling pathway operating between the basal and suprabasal cells. Furthermore, using specific expression signatures, we identified a new set of late differentiation markers and mapped their chromosomal loci, as well as a new set of melanocyte-specific markers. The data represent a quantum jump in understanding the mechanisms of epidermal differentiation.

  16. Toksisk epidermal nekrolyse

    DEFF Research Database (Denmark)

    Bygum, Anette; Andersen, Klaus Ejner

    2006-01-01

    Toxic epidermal necrolysis (TEN) is a rare, mostly drug-induced life-threatening mucocutaneous reaction with generalised symptoms and internal organ involvement. Current treatment strategy focuses on supportive intensive care with close collaboration among many specialties. Specific therapies...

  17. The proliferative effects of Pyropia yezoensis peptide on IEC-6 cells are mediated through the epidermal growth factor receptor signaling pathway.

    Science.gov (United States)

    Lee, Min-Kyeong; Kim, In-Hye; Choi, Youn-Hee; Choi, Jeong-Wook; Kim, Young-Min; Nam, Taek-Jeong

    2015-04-01

    For a number of years, seaweed has been used as a functional food in Asian countries, particularly in Korea, Japan and China. Pyropia yezoensis is a marine red alga that has potentially beneficial biological activities. In this study, we examined the mechanisms through which a Pyropia yezoensis peptide [PYP1 (1-20)] induces the proliferation of IEC-6 cells, a rat intestinal epithelial cell line, and the involvement of the epidermal growth factor receptor (EGFR) signaling pathway. First, cell viability assay revealed that PYP1 (1-20) induced cell proliferation in a concentration-dependent manner. Subsequently, we examined the mechanisms responsible for this induction of proliferation induced by PYP1 (1-20). EGFR is widely expressed in mammalian epithelial tissues, and the binding of this ligand affects a variety of cell physiological parameters, such as cell growth and proliferation. PYP1 (1-20) increased the expression of EGFR, Shc, growth factor receptor-bound protein 2 (Grb2) and son of sevenless (SOS). EGFR also induced the activation of the Ras signaling pathway through Raf, MEK and extracellular signal-regulated kinase (ERK) phosphorylation. In addition, cell cycle analysis revealed the expression of cell cycle-related proteins. The results demonstrated an increased number of cells in the G1 phase and an enhanced cell proliferation. In addition, the upregulation of cyclin D, cyclin E, Cdk2, Cdk4 and Cdk6 was observed accompanied by a decreased in p21 and p27 expression. These findings suggest that PYP1 (1-20) stimulates the proliferation of rat IEC-6 cells by activating the EGFR signaling pathway. Therefore, PYP1 (1-20) may be a potential source for the development of bio-functional foods which promotes the proliferation of intestinal epithelial cells.

  18. Involvement of cysteine-rich protein 61 in the epidermal growth factor-induced migration of human anaplastic thyroid cancer cells.

    Science.gov (United States)

    Chin, Li-Han; Hsu, Sung-Po; Zhong, Wen-Bin; Liang, Yu-Chih

    2016-05-01

    Anaplastic thyroid cancer (ATC) is among the most aggressive types of malignant cancer. Epidermal growth factor (EGF) plays a crucial role in the pathogenesis of ATC, and patients with thyroid carcinoma typically exhibit increased cysteine-rich protein 61 (Cyr61). In this study, we found that EGF treatment induced cell migration, stress fiber formation, Cyr61 mRNA and protein expressions, and Cyr61 protein secretion in ATC cells. The recombinant Cyr61 protein significantly induced cell migration; however, inhibition of Cyr61 activity by a Cyr61-specific antibody abrogated EGF-induced cell migration. EGF treatment also affected epithelial-to-mesenchymal transition (EMT)-related marker protein expression, as evidenced by an increase in vimentin and a decrease in E-cadherin expression. Inhibition of Cyr61 expression by Cyr61 siRNA decreased cell migration and reversed the EMT-related marker protein expression. EGF treatment increased the phosphorylation of the extracellular signal-regulated kinase (ERK) and cAMP response element-binding protein (CREB), and finally activated Cyr61 promoter plasmid activity. Our results suggest that Cyr61 is induced by EGF through the ERK/CREB signal pathway and that it plays a crucial role in the migration and invasion of ATC cells; moreover, Cyr61 might be a therapeutic target for metastatic ATC.

  19. Infiltration anesthetic lidocaine inhibits cancer cell invasion by modulating ectodomain shedding of heparin-binding epidermal growth factor-like growth factor (HB-EGF).

    Science.gov (United States)

    Mammoto, Tadanori; Higashiyama, Shigeki; Mukai, Mutsuko; Mammoto, Akiko; Ayaki, Masako; Mashimo, Takashi; Hayashi, Yukio; Kishi, Yoshihiko; Nakamura, Hiroyuki; Akedo, Hitoshi

    2002-09-01

    Although the mechanism is unknown, infiltration anesthetics are believed to have membrane-stabilizing action. We report here that such a most commonly used anesthetic, lidocaine, effectively inhibited the invasive ability of human cancer (HT1080, HOS, and RPMI-7951) cells at concentrations used in surgical operations (5-20 mM). Ectodomain shedding of heparin-binding epidermal growth factor-like growth factor (HB-EGF) from the cell surface plays an important role in invasion by HT1080 cells. Lidocaine reduced the invasion ability of these cells by partly inhibiting the shedding of HB-EGF from the cell surface and modulation of intracellular Ca2+ concentration contributed to this action. The anesthetic action of lidocaine (sodium channel blocking ability) did not contribute to this anti-invasive action. In addition, lidocaine (5-30 mM), infiltrated around the inoculation site, inhibited pulmonary metastases of murine osteosarcoma (LM 8) cells in vivo. These data point to previously unrecognized beneficial actions of lidocaine and suggest that lidocaine might be an ideal infiltration anesthetic for surgical cancer operations.

  20. New insights in the structure and biology of the high affinity receptor for IgE (Fc epsilon RI) on human epidermal Langerhans cells.

    Science.gov (United States)

    Bieber, T; Kraft, S; Jürgens, M; Strobel, I; Haberstok, J; Tomov, H; Regele, D; de la Salle, H; Wollenberg, A; Hanau, D

    1996-10-01

    The recent structural and functional analysis of the high affinity receptor for IgE (Fc epsilon RI) expressed on human epidermal Langerhans cells (LC) revealed new aspects of the biology of this structure. In contrast to basophils and mast cells where this receptor seems to be expressed constitutively at a constant level, the expression of Fc epsilon RI on LC varies on the donor and the inflammatory environment of the cells and lacks the classical beta-chain. This also implies functional differences most probably related to the expression level. Although the signalling pathway seems to be similar to that of basophils or mast cells, LC from individuals with atopic dermatitis are fully activated by receptor ligation while LC from normal individuals fail to exhibit calcium mobilization under the same conditions. Finally, LC from normal and atopic individuals use Fc epsilon RI to maximize antigen uptake via specific IgE and subsequent presentation to T cells. Thus, Fc epsilon RI expressed on LC differs in terms of structure and function from that expressed on effector cells of anaphylaxis.

  1. Eicosopentaneoic Acid and Other Free Fatty Acid Receptor Agonists Inhibit Lysophosphatidic Acid- and Epidermal Growth Factor-Induced Proliferation of Human Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Mandi M. Hopkins

    2016-01-01

    Full Text Available Many key actions of ω-3 (n-3 fatty acids have recently been shown to be mediated by two G protein-coupled receptors (GPCRs in the free fatty acid receptor (FFAR family, FFA1 (GPR40 and FFA4 (GPR120. n-3 Fatty acids inhibit proliferation of human breast cancer cells in culture and in animals. In the current study, the roles of FFA1 and FFA4 were investigated. In addition, the role of cross-talk between GPCRs activated by lysophosphatidic acid (LPA, and the tyrosine kinase receptor activated by epidermal growth factor (EGF, was examined. In MCF-7 and MDA-MB-231 human breast cancer cell lines, both LPA and EGF stimulated proliferation, Erk activation, Akt activation, and CCN1 induction. LPA antagonists blocked effects of LPA and EGF on proliferation in MCF-7 and MDA-MB-231, and on cell migration in MCF-7. The n-3 fatty acid eicosopentaneoic acid inhibited LPA- and EGF-induced proliferation in both cell lines. Two synthetic FFAR agonists, GW9508 and TUG-891, likewise inhibited LPA- and EGF-induced proliferation. The data suggest a major role for FFA1, which was expressed by both cell lines. The results indicate that n-3 fatty acids inhibit breast cancer cell proliferation via FFARs, and suggest a mechanism involving negative cross-talk between FFARS, LPA receptors, and EGF receptor.

  2. Epidermal growth factor potentiates in vitro metastatic behaviour of human prostate cancer PC-3M cells: involvement of voltage-gated sodium channel

    Directory of Open Access Journals (Sweden)

    Uysal-Onganer Pinar

    2007-11-01

    Full Text Available Abstract Background Although a high level of functional voltage-gated sodium channel (VGSC expression has been found in strongly metastatic human and rat prostate cancer (PCa cells, the mechanism(s responsible for the upregulation is unknown. The concentration of epidermal growth factor (EGF, a modulator of ion channels, in the body is highest in prostatic fluid. Thus, EGF could be involved in the VGSC upregulation in PCa. The effects of EGF on VGSC expression in the highly metastatic human PCa PC-3M cell line, which was shown previously to express both functional VGSCs and EGF receptors, were investigated. A quantitative approach, from gene level to cell behaviour, was used. mRNA levels were determined by real-time PCR. Protein expression was studied by Western blots and immunocytochemistry and digital image analysis. Functional assays involved measurements of transverse migration, endocytic membrane activity and Matrigel invasion. Results Exogenous EGF enhanced the cells' in vitro metastatic behaviours (migration, endocytosis and invasion. Endogenous EGF had a similar involvement. EGF increased VGSC Nav1.7 (predominant isoform in PCa mRNA and protein expressions. Co-application of the highly specific VGSC blocker tetrodotoxin (TTX suppressed the effect of EGF on all three metastatic cell behaviours studied. Conclusion 1 EGF has a major involvement in the upregulation of functional VGSC expression in human PCa PC-3M cells. (2 VGSC activity has a significant intermediary role in potentiating effect of EGF in human PCa.

  3. Cell-free synthesis of functional human epidermal growth factor receptor: Investigation of ligand-independent dimerization in Sf21 microsomal membranes using non-canonical amino acids

    Science.gov (United States)

    Quast, Robert B.; Ballion, Biljana; Stech, Marlitt; Sonnabend, Andrei; Varga, Balázs R.; Wüstenhagen, Doreen A.; Kele, Péter; Schiller, Stefan M.; Kubick, Stefan

    2016-01-01

    Cell-free protein synthesis systems represent versatile tools for the synthesis and modification of human membrane proteins. In particular, eukaryotic cell-free systems provide a promising platform for their structural and functional characterization. Here, we present the cell-free synthesis of functional human epidermal growth factor receptor and its vIII deletion mutant in a microsome-containing system derived from cultured Sf21 cells. We provide evidence for embedment of cell-free synthesized receptors into microsomal membranes and asparagine-linked glycosylation. Using the cricket paralysis virus internal ribosome entry site and a repetitive synthesis approach enrichment of receptors inside the microsomal fractions was facilitated thereby providing analytical amounts of functional protein. Receptor tyrosine kinase activation was demonstrated by monitoring receptor phosphorylation. Furthermore, an orthogonal cell-free translation system that provides the site-directed incorporation of p-azido-L-phenylalanine is characterized and applied to investigate receptor dimerization in the absence of a ligand by photo-affinity cross-linking. Finally, incorporated azides are used to generate stable covalently linked receptor dimers by strain-promoted cycloaddition using a novel linker system. PMID:27670253

  4. Dactylone inhibits epidermal growth factor-induced transformation and phenotype expression of human cancer cells and induces G1-S arrest and apoptosis.

    Science.gov (United States)

    Fedorov, Sergey N; Shubina, Larisa K; Bode, Ann M; Stonik, Valentin A; Dong, Zigang

    2007-06-15

    The marine natural chamigrane-type sesquiterpenoid, dactylone, is closely related to secondary metabolites of some edible species of red algae. In the present study, the effect of dactylone was tested on the mouse skin epidermal JB6 P+ Cl41 cell line and its stable transfectants as well as on several human tumor cell lines, including lung (H460), colon (HCT-116), and skin melanomas (SK-MEL-5 and SK-MEL-28). This natural product was effective at nontoxic doses as a cancer-preventive agent, which exerted its actions, at least in part, through the inhibition of cyclin D3 and Cdk4 expression and retinoblastoma tumor suppressor protein (Rb) phosphorylation. The inhibition of these cell cycle components was followed by cell cycle arrest at the G1-S transition with subsequent p53-independent apoptosis. Therefore, these data showed that application of dactylone and related compounds may lead to decreased malignant cell transformation and/or decreased tumor cell proliferation.

  5. Epidermal growth factor upregulates motility of Mat-LyLu rat prostate cancer cells partially via voltage-gated Na+ channel activity

    Science.gov (United States)

    Ding, Yanning; Brackenbury, William J.; Onganer, Pinar U.; Montano, Ximena; Porter, Louise M.; Bates, Lucy F.; Djamgoz, Mustafa B. A.

    2014-01-01

    The main aim of this investigation was to determine whether a functional relationship existed between epidermal growth factor (EGF) and voltage-gated sodium channel (VGSC) upregulation, both associated with strongly metastatic prostate cancer cells. Incubation with EGF for 24 h more than doubled VGSC current density. Similar treatment with EGF significantly and dose-dependently enhanced the cells’ migration through Transwell filters. Both the patch clamp recordings and the migration assay suggested that endogenous EGF played a similar role. Importantly, co-application of EGF and tetrodotoxin, a highly selective VGSC blocker, abolished 65% of the potentiating effect of EGF. It is suggested that a significant portion of the EGF-induced enhancement of migration occurred via VGSC activity. PMID:17960590

  6. The importance of molecular profiling in predicting response to epidermal growth factor receptor family inhibitors in non-small-cell lung cancer: focus on clinical trial results.

    Science.gov (United States)

    Tsao, Anne S; Papadimitrakopoulou, Vassiliki

    2013-07-01

    In recent years, the epidermal growth factor receptor (EGFR) family has become a key focus of non-small-cell lung cancer biology and targeted therapies, such as the reversible EGFR tyrosine kinase inhibitors erlotinib and gefitinib. Initially, response to these agents was associated with certain demographic and clinical characteristics; subsequently, it was discovered that these subgroups were more likely to harbor specific mutations in the EGFR gene that enhanced tumor response. However, the presence of these mutations does not equate to therapeutic success. Other aspects of EGFR family signaling, including other types of EGFR mutations, EGFR protein expression, EGFR gene amplification, mediators of downstream signaling, and other receptors with similar downstream pathways may all play a role in response or resistance to treatment. The identification of these and other molecular determinants is driving the development of novel therapies designed to achieve improved clinical outcomes in patients.

  7. Development of epidermal growth factor receptor tyrosine kinase inhibitors against EGFR T790M. Mutation in non small-cell lung carcinoma

    Directory of Open Access Journals (Sweden)

    Wang Yuli

    2016-01-01

    Full Text Available Individualized therapies targeting epidermal growth factor receptor (EGFR mutations show promises for the treatment of non small-cell lung carcinoma (NSCLC. However, disease progression almost invariably occurs 1 year after tyrosine kinase inhibitor (TKI treatment. The most prominent mechanism of acquired resistance involves the secondary EGFR mutation, namely EGFR T790M, which accounts for 50%–60% of resistant tumors. A large amount of studies have focused on the development of effective strategies to treat TKI-resistant EGFR T790M mutation in lung tumors. Novel generations of EGFR inhibitors are producing encouraging results in patients with acquired resistance against EGFR T790M mutation. This review will summarize the novel inhibitors, which might overcome resistance against EGFR T790M mutation.

  8. Genetic polymorphism in the epidermal growth factor receptor gene predicts outcome in advanced non-small cell lung cancer patients treated with erlotinib

    DEFF Research Database (Denmark)

    Winther-Larsen, Anne; Nissen, Peter H.; Jakobsen, Kristine Raaby;

    2015-01-01

    OBJECTIVES: Epidermal growth factor receptor (EGFR) mutations are important predictors of treatment response to tyrosine kinase inhibitors (TKIs) in patients with non-small cell lung cancer (NSCLC). However, some patients with mutations do not respond and some patients without mutations show...... with advanced NSCLC. Genotypes were correlated with clinical characteristics, toxicity and outcome. A multivariate analysis was performed using Cox proportional hazards model while adjusting for clinically relevant factors including EGFR mutation status. RESULTS: 181946CT or TT genotypes showed an association...... response. We therefore need additional biomarkers to improve the selection of these patients for treatment. A promising candidate could be germline genetic variations in the EGFR gene that can alter protein expression or function and may influence the response to TKIs. Thus, the aim of this study...

  9. Effect of epidermal growth factor on the labeling of the various RNA species and of nuclear proteins in primary rat astroglial cell cultures

    Energy Technology Data Exchange (ETDEWEB)

    Avola, R.; Condorelli, D.F.; Turpeenoja, L.; Ingrao, F.; Reale, S.; Ragusa, N.; Giuffrida Stella, A.M.

    1988-05-01

    This study investigated the effects of epidermal growth factor (EGF) on the labeling of various RNA species and of nuclear proteins in primary rat astroglial cell cultures. After 12 hours of EGF treatment in serum-free medium or chemically defined medium, significant increase in RNA labeling, and also in acid-soluble radioactivity and RNA content, was observed. The ratio RNA/DNA was significantly higher in EGF-treated cultures compared with controls. Ribosomal RNAs (28S and 18S), polyadenylated, and nonpolyadenylated RNAs showed a higher specific radioactivity in EGF-treated cultures. Among the nuclear proteins, the labeling of basic proteins was enhanced by EGF treatment, whereas that of total nuclear acidic protein (NHPs) was less modified, except for some NHPs separated by gel electrophoresis with a molecular weight (MW) approximately 95-83 and 44 kd, which were significantly more labeled in EGF-treated cultures.

  10. Toxic epidermal necrolysis.

    Science.gov (United States)

    Castelain, Florence; Humbert, Philippe

    2012-11-01

    Toxic epidermal necrolysis (TEN) is a severe mucocutaneous drug-induced syndrome that causes massive keratinocyte apoptosis and therefore hydro-electrolytic disorders and systemic infection. TEN approximately affects one to two cases per million per year. Mortality rate may reach thirty percent of cases. Thus, TEN constitutes a therapeutic emergency at diagnosis. Typically, clinical examination shows a mucocutaneous detachment involving more than thirty percent of body area. Definitive diagnosis is made on cutaneous biopsy with histological exam that shows the blister of necrotic keratinocytes. Main differential diagnosis are acute staphylococcus epidermis, acute generalized exanthematous pustulosis, linear IgA bullous dermatosis, paraneoplastic pemphigus, bullous fixed pigmented erythema, acute lupus erythematosus. In the early days, SCORTEN gives a good estimation and is now widely used as prognostic score. Drugs are generally considered as the main etiology of TEN but in some cases bacterial or viral infections could be involved. Physiopathology remains unclear even if recent advances have reported the possible implication of immune pathways based on activation of T and NK cells. Treatment of TEN requires to be instituted as soon as the diagnosis is made and the patient is preferentially referred to a specialized unit. Supportive care consist of covering areas of cutaneous detachment. No other therapy has demonstrated its efficiency, but high-dose intravenous immunoglobulin might improve the prognosis.

  11. Combined targeting of adenoviruses to integrins and epidermal growth factor receptors increases gene transfer into primary glioma cells and spheroids

    NARCIS (Netherlands)

    Grill, J; Van Beusechem, VW; Van de Valk, P; Dirven, CMF; Leonhart, A; Pherai, DS; Haisma, HJ; Pinedo, HM; Curiel, DT; Gerritsen, WR

    Adenoviral-mediated gene transfer is suboptimal in human glioma and limits in vivo gene therapy approaches. There is a need for targeted vectors able to enhance gene transfer into the tumor as well as to lower the viral load in the surrounding normal tissues. We evaluated primary human tumor samples

  12. ZEB1 Mediates Acquired Resistance to the Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitors in Non-Small Cell Lung Cancer.

    Directory of Open Access Journals (Sweden)

    Takeshi Yoshida

    Full Text Available Epithelial-mesenchymal transition (EMT is one mechanism of acquired resistance to inhibitors of the epidermal growth factor receptor-tyrosine kinases (EGFR-TKIs in non-small cell lung cancer (NSCLC. The precise mechanisms of EMT-related acquired resistance to EGFR-TKIs in NSCLC remain unclear. We generated erlotinib-resistant HCC4006 cells (HCC4006ER by chronic exposure of EGFR-mutant HCC4006 cells to increasing concentrations of erlotinib. HCC4006ER cells acquired an EMT phenotype and activation of the TGF-β/SMAD pathway, while lacking both T790M secondary EGFR mutation and MET gene amplification. We employed gene expression microarrays in HCC4006 and HCC4006ER cells to better understand the mechanism of acquired EGFR-TKI resistance with EMT. At the mRNA level, ZEB1 (TCF8, a known regulator of EMT, was >20-fold higher in HCC4006ER cells than in HCC4006 cells, and increased ZEB1 protein level was also detected. Furthermore, numerous ZEB1 responsive genes, such as CDH1 (E-cadherin, ST14, and vimentin, were coordinately regulated along with increased ZEB1 in HCC4006ER cells. We also identified ZEB1 overexpression and an EMT phenotype in several NSCLC cells and human NSCLC samples with acquired EGFR-TKI resistance. Short-interfering RNA against ZEB1 reversed the EMT phenotype and, importantly, restored erlotinib sensitivity in HCC4006ER cells. The level of micro-RNA-200c, which can negatively regulate ZEB1, was significantly reduced in HCC4006ER cells. Our results suggest that increased ZEB1 can drive EMT-related acquired resistance to EGFR-TKIs in NSCLC. Attempts should be made to explore targeting ZEB1 to resensitize TKI-resistant tumors.

  13. REST is up-regulated by epidermal growth factor in HeLa cells and inhibits apoptosis by influencing histone H3 acetylation.

    Science.gov (United States)

    Baiula, Monica; Carbonari, Gioia; Dattoli, Samantha D; Calienni, Maria; Bedini, Andrea; Spampinato, Santi

    2012-08-01

    REST (repressor element 1-silencing transcription factor) is a transcription factor that recruits histone deacetylases to silence gene transcription. REST appears to play a paradoxical role in cancer cells: it exhibits tumor suppressor activity or promotes tumorigenesis, depending upon the setting. The extracellular signaling molecules that control REST gene expression in cancer cells remain poorly understood. In this study, we report that REST expression in HeLa cells is elevated in cells exposed to epidermal growth factor or serum, whereas the rate of cell apoptosis is low. Apoptosis induced by serum withdrawal is significantly increased in HeLa cells treated with an antisense phosphorothioate oligodeoxynucleotide (AS ODN) capable of down-regulating REST expression, whereas in HeLa cells transfected with a REST expressing plasmid, REST overexpression reduces the marked apoptosis caused, in absence of serum, by exposure to an anti-Fas receptor antibody imitating the Fas ligand activity plus PD 98059, a blocker of extracellular signal-regulated kinase 1/2 activation. REST knockdown also reduces mRNA levels of the antiapoptotic protein Bcl-X(L) whereas in HeLa cells overexpressing REST, the reduction of Bcl-X(L) mRNA caused by the anti-Fas receptor antibody plus PD 98059 is significantly decreased. Finally, we report that acetylation of histone H3 is increased in HeLa cells exposed to AS ODN or anti-Fas receptor antibody, whereas it is reduced in cells transfected with the REST expressing plasmid. Our findings indicate that REST is a novel gene regulated by EGF in HeLa cells that potentially contributes to the modulation of apoptosis via epigenetic mechanisms.

  14. Modulation by epidermal growth factor of the basal 1,25(OH)2D3 receptor level and the heterologous up-regulation of the 1,25(OH)2D3 receptor in clonal osteoblast-like cells

    NARCIS (Netherlands)

    J.P.T.M. van Leeuwen (Hans); H.A.P. Pols (Huib); J.P. Schilte (J.); T.J. Visser (Theo); J.C. Birkenhäger (Jan)

    1991-01-01

    textabstractThe effects of epidermal growth factor (EGF) on basal 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) receptor level and on parathyroid hormone (PTH)-induced 1,25-(OH)2D3 (OH)2D3 receptor up-regulation were studied in the phenotypically osteoblastic cell line UMR 106. EGF in concentrations

  15. Epidermal growth factor receptor tyrosine kinase (EGFR-TK) mutation testing in adults with locally advanced or metastatic non-small cell lung cancer: A systematic review and cost-effectiveness analysis

    NARCIS (Netherlands)

    M. Westwood (Marie); M.A. Joore (Manuela); P. Whiting (Penny); T. van Asselt (Thea); B.L.T. Ramaekers (Bram); N. Armstrong (Nigel); K. Misso (Kate); J.L. Severens (Hans); J. Kleijnen (Jos)

    2014-01-01

    markdownabstract__Abstract__ Background: Non-small cell lung cancer (NSCLC) is the most common form of lung cancer. Some epidermal growth factor receptor tyrosine kinase (EGFR-TK) mutations make tumours responsive to treatment with EGFR-TK inhibitors (EGFR-TKIs) but less responsive to treatment wit

  16. Epidermal growth factor receptor tyrosine kinase (EGFR-TK) mutation testing in adults with locally advanced or metastatic non-small cell lung cancer : a systematic review and cost-effectiveness analysis

    NARCIS (Netherlands)

    Westwood, Marie; Joore, Manuela; Whiting, Penny; van Asselt, Thea; Ramaekers, Bram; Armstrong, Nigel; Misso, Kate; Severens, Johan; Kleijnen, Jos

    2014-01-01

    BACKGROUND: Non-small cell lung cancer (NSCLC) is the most common form of lung cancer. Some epidermal growth factor receptor tyrosine kinase (EGFR-TK) mutations make tumours responsive to treatment with EGFR-TK inhibitors (EGFR-TKIs) but less responsive to treatment with standard chemotherapy. Patie

  17. Epidermal growth factor receptor tyrosine kinase (EGFR-TK) mutation testing in adults with locally advanced or metastatic non-small cell lung cancer: A systematic review and cost-effectiveness analysis

    NARCIS (Netherlands)

    M. Westwood (Marie); M.A. Joore (Manuela); P. Whiting (Penny); T. van Asselt (Thea); B.L.T. Ramaekers (Bram); N. Armstrong (Nigel); K. Misso (Kate); J.L. Severens (Hans); J. Kleijnen (Jos)

    2014-01-01

    markdownabstract__Abstract__ Background: Non-small cell lung cancer (NSCLC) is the most common form of lung cancer. Some epidermal growth factor receptor tyrosine kinase (EGFR-TK) mutations make tumours responsive to treatment with EGFR-TK inhibitors (EGFR-TKIs) but less responsive to treatment wit

  18. ARF6 promotes the formation of Rac1 and WAVE-dependent ventral F-actin rosettes in breast cancer cells in response to epidermal growth factor.

    Directory of Open Access Journals (Sweden)

    Valentina Marchesin

    Full Text Available Coordination between actin cytoskeleton assembly and localized polarization of intracellular trafficking routes is crucial for cancer cell migration. ARF6 has been implicated in the endocytic recycling of surface receptors and membrane components and in actin cytoskeleton remodeling. Here we show that overexpression of an ARF6 fast-cycling mutant in MDA-MB-231 breast cancer-derived cells to mimick ARF6 hyperactivation observed in invasive breast tumors induced a striking rearrangement of the actin cytoskeleton at the ventral cell surface. This phenotype consisted in the formation of dynamic actin-based podosome rosette-like structures expanding outward as wave positive for F-actin and actin cytoskeleton regulatory components including cortactin, Arp2/3 and SCAR/WAVE complexes and upstream Rac1 regulator. Ventral rosette-like structures were similarly induced in MDA-MB-231 cells in response to epidermal growth factor (EGF stimulation and to Rac1 hyperactivation. In addition, interference with ARF6 expression attenuated activation and plasma membrane targeting of Rac1 in response to EGF treatment. Our data suggest a role for ARF6 in linking EGF-receptor signaling to Rac1 recruitment and activation at the plasma membrane to promote breast cancer cell directed migration.

  19. Exposure of JB-6 mouse epidermal cells to 12-O-tetradecanoyl-phorbol-13-acetate is not accompanied by a significant change in total DNA-cytosine methylation.

    Science.gov (United States)

    Bondy, G P; Denhardt, D T

    1983-12-01

    The extent of methylation of the cytosine bases in DNA is believed to be a major factor influencing gene expression in eukaryotic cells. We have asked whether the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) alters the amount of 5-methylcytosine in DNA. The amount and relative distribution of 5-methylcytosine in the DNA of two subclones of the JB-6 mouse epidermal cell line were determined respectively by high performance liquid chromatography and digestion with the restriction enzymes MspI and HpaII. Exposure to TPA for up to several cell generations had no detectable effect on the degree of DNA methylation (3.9% of the total cytosine) in the two JB-6 lines or Friend erythroleukemia cells. Reduced methylation was readily detected in DNA extracted from cells exposed to 5-azacytidine. The data suggest that tumor promotion (at least that induced by TPA) is likely not the consequence of a generalized elevation or reduction in the amount of 5-methyl-cytosine in the DNA.

  20. Activation of nonreceptor tyrosine kinase Bmx/Etk mediated by phosphoinositide 3-kinase, epidermal growth factor receptor, and ErbB3 in prostate cancer cells.

    Science.gov (United States)

    Jiang, Xinnong; Borgesi, Robert A; McKnight, Nicole C; Kaur, Ramneet; Carpenter, Christopher L; Balk, Steven P

    2007-11-09

    Pathways activated downstream of constitutively active phosphatidylinositol (PI) 3-kinase in PTEN-deficient prostate cancer (PCa) cells are possible therapeutic targets. We found that the nonreceptor Tec family tyrosine kinase Bmx/Etk was activated by tyrosine phosphorylation downstream of Src and PI 3-kinase in PTEN-deficient LNCaP and PC3 PCa cells and that Bmx down-regulation by short interfering RNA markedly inhibited LNCaP cell growth. Bmx also associated with ErbB3 in LNCaP cells, and heregulin-beta1 enhanced this interaction and further stimulated Bmx activity. Epidermal growth factor (EGF) similarly stimulated an interaction between Bmx and EGF receptor and rapidly increased Bmx kinase activity. Bmx stimulation in response to heregulin-beta1 and EGF was Src-dependent, and heregulin-beta1 stimulation of Bmx was also PI 3-kinase-dependent. In contrast, the rapid tyrosine phosphorylation and activation of Bmx in response to EGF was PI 3-kinase-independent. Taken together, these results demonstrate that Bmx is a critical downstream target of the constitutively active PI 3-kinase in PTEN-deficient PCa cells and further show that Bmx is recruited by the EGF receptor and ErbB3 and activated in response to their respective ligands. Therefore, Bmx may be a valuable therapeutic target in PCa and other epithelial malignancies in which PI 3-kinase or EGF receptor family pathways are activated.

  1. Epidermal melanin absorption in human skin

    Science.gov (United States)

    Norvang Nilsen, Lill T.; Fiskerstrand, Elisanne J.; Nelson, J. Stuart; Berns, Michael W.; Svaasand, Lars O.

    1996-01-01

    The principle of laser induced selective photothermolysis is to induced thermal damage to specific targets in such a manner that the temperature of the surrounding tissue is maintained below the threshold for thermal damage. The selectivity is obtained by selection of a proper wavelength and pulse duration. The technique is presently being used in the clinic for removal of port-wine stains. The presence of melanin in the epidermal layer can represent a limitation to the selectivity. Melanin absorption drops off significantly with increasing wavelength, but is significant in the entire wavelength region where the blood absorption is high. Treatment of port-wine stain in patients with high skin pigmentation may therefore give overheating of the epidermis, resulting in epidermal necrosis. Melanosomal heating is dependent on the energy and duration of the laser pulse. The heating mechanism for time scales less than typically 1 microsecond(s) corresponds to a transient local heating of the individual melanosomes. For larger time scales, heat diffusion out of the melanosomes become of increased importance, and the temperature distribution will reach a local steady state condition after typically 10 microsecond(s) . For even longer pulse duration, heat diffusing from neighboring melanosomes becomes important, and the temperature rise in a time scale from 100 - 500 microsecond(s) is dominated by this mechanism. The epidermal heating during the typical 450 microsecond(s) pulse used for therapy is thus dependent on the average epidermal melanin content rather than on the absorption coefficient of the individual melanosomes. This study will present in vivo measurements of the epidermal melanin absorption of human skin when exposed to short laser pulses (< 0.1 microsecond(s) ) from a Q-switched ruby laser and with long laser pulses (approximately 500 microsecond(s) ) from a free-running ruby laser or a long pulse length flashlamp pumped dye laser. The epidermal melanin

  2. Transcatheter arterial embolization combined with radiofrequency ablation activates CD8+ T-cell infiltration surrounding residual tumors in the rabbit VX2 liver tumors

    Directory of Open Access Journals (Sweden)

    Duan XH

    2016-05-01

    Full Text Available Xu-Hua Duan,1,2 Teng-Fei Li,2 Guo-Feng Zhou,1,* Xin-Wei Han,2,* Chuan-Sheng Zheng,1 Peng-fei Chen,2 Gan-Sheng Feng11Department of Interventional Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 2Department of Interventional Radiology, The First Affiliated Hospital, Zhengzhou University, Henan Province, Zhengzhou, People’s Republic of China*These authors contributed equally to this work Purpose: To evaluate the effect of transcatheter arterial embolization (TAE combined with radiofrequency ablation (RFA treatment (TAE + RFA on the expression of heat shock protein 70 (HSP70 in residual tumors and explore the relationship between the HSP70 and CD8+ T-cell infiltrate surrounding residual tumors in the rabbit VX2 liver tumor model.Materials and methods: Animals with VX2 liver tumors were randomized into four groups (control, TAE, RFA, and TAE + RFA with 15 rabbits in each group. Five rabbits in each group were sacrificed on days 1, 3, and 7 after treatment. HSP70 expression and infiltration of CD8+ T-cells in the liver and residual tumors surrounding the necrosis zone were detected by immunohistochemistry staining. The maximal diameters of tumor necrosis, numbers of metastases, and tumor growth rate were compared on day 7 after treatment.Results: TAE + RFA achieved larger maximal diameter of tumor necrosis, lower tumor growth rate, and fewer metastatic lesions, compared with other treatments on day 7. The number of CD8+ T-cells in the TAE + RFA group was significantly higher than in other groups on days 1, 3, and 7. There was a positive correlation between HSP70 expression level and infiltration of CD8+ T-cells surrounding the residual tumor on day 1 (r=0.9782, P=0.012, day 3 (r=0.93, P=0.021, and day 7 (r=0.8934, P=0.034.Conclusion: In the rabbit VX2 liver tumor model, TAE + RFA activated the highest number of CD8+ T-cells surrounding residual tumors. TAE + RFA appears to be a beneficial

  3. Involvement of the antioxidative property of morusin in blocking phorbol ester-induced malignant transformation of JB6 P(+) mouse epidermal cells.

    Science.gov (United States)

    Cheng, Pai-Shan; Hu, Chao-Chin; Wang, Chau-Jong; Lee, Yean-Jang; Chung, Wei-Chia; Tseng, Tsui-Hwa

    2017-02-25

    Chemoprevention has been acknowledged as an important and practical strategy for managing cancer. We have previously synthesized morusin, a prenylated flavonoid that exhibits anti-cancer progression activity. In the present study, we evaluated the anti-cancer promotion potential of morusin by using the mouse epidermal JB6 P(+) cell model. Extensive evidence shows that tumor promotion by phorbol esters is due to the stimulation of reactive oxygen species (ROS). Therefore, the effect of morusin on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ROS production was assessed. Noncytotoxic concentrations of morusin were found to dose-dependently reduce TPA-induced ROS production. Moreover, morusin inhibited TPA-induced activator protein-1 (AP-1) and nuclear factor-kappa B (NF-κB) activation, which can mediate cell proliferation and malignant transformation. Furthermore, morusin inhibited the TPA upregulation of cyclooxygenase 2 (COX-2), which may be regulated by AP-1 and NF-κB. In addition, noncytotoxic concentrations of morusin reduced the TPA-promoted cell growth of JB6 P(+) cells and inhibited TPA-induced malignant properties, such as cytoskeletal rearrangement and cell migration of JB6 P(+) cells. Similar to the effects of glutathione (GSH) pretreatment, morusin inhibited TPA-induced expression of N-cadeherin and vimentin, which are malignant cell surface proteins. Finally, morusin treatment dose-dependently suppressed the TPA-induced anchorage-independent cell transformation of JB6 P(+) cells. In conclusion, our results evidence that morusin possesses anti-cancer promotion potential because of its antioxidant property, which mediates multiple transformation-associated gene expression.

  4. Activation of H-Ras and Rac1 correlates with epidermal growth factor-induced invasion in Hs578T and MDA-MB-231 breast carcinoma cells.

    Science.gov (United States)

    Koh, Min-Soo; Moon, Aree

    2011-03-01

    There is considerable experimental evidence that hyperactive Ras proteins promote breast cancer growth and development including invasiveness, despite the low frequency of mutated forms of Ras in breast cancer. We have previously shown that H-Ras, but not N-Ras, induces an invasive phenotype mediated by small GTPase Rac1 in MCF10A human breast epithelial cells. Epidermal growth factor (EGF) plays an important role in aberrant growth and metastasis formation of many tumor types including breast cancer. The present study aims to investigate the correlation between EGF-induced invasiveness and Ras activation in four widely used breast cancer cell lines. Upon EGF stimulation, invasive abilities and H-Ras activation were significantly increased in Hs578T and MDA-MB-231 cell lines, but not in MDA-MB-453 and T47D cell lines. Using small interfering RNA (siRNA) to target H-Ras, we showed a crucial role of H-Ras in the invasive phenotype induced by EGF in Hs578T and MDA-MB-231 cells. Moreover, siRNA-knockdown of Rac1 significantly inhibited the EGF-induced invasiveness in these cells. Taken together, this study characterized human breast cancer cell lines with regard to the relationship between H-Ras activation and the invasive phenotype induced by EGF. Our data demonstrate that the activation of H-Ras and the downstream molecule Rac1 correlates with EGF-induced breast cancer cell invasion, providing important information on the regulation of malignant progression in mammary carcinoma cells.

  5. Impaired degradation followed by enhanced recycling of epidermal growth factor receptor caused by hypo-phosphorylation of tyrosine 1045 in RBE cells

    Directory of Open Access Journals (Sweden)

    Gui Anping

    2012-05-01

    Full Text Available Abstract Background Since cholangiocarcinoma has a poor prognosis, several epidermal growth factor receptor (EGFR-targeted therapies with antibody or small molecule inhibitor treatment have been proposed. However, their effect remains limited. The present study sought to understand the molecular genetic characteristics of cholangiocarcinoma related to EGFR, with emphasis on its degradation and recycling. Methods We evaluated EGFR expression and colocalization by immunoblotting and immunofluorescence, cell surface EGFR expression by fluorescence-activated cell sorting (FACS, and EGFR ubiquitination and protein binding by immunoprecipitation in the human cholangiocarcinoma RBE and immortalized cholangiocyte MMNK-1 cell lines. Monensin treatment and Rab11a depletion by siRNA were adopted for inhibition of EGFR recycling. Results Upon stimulation with EGF, ligand-induced EGFR degradation was impaired and the expression of phospho-tyrosine 1068 and phospho-p44/42 MAPK was sustained in RBE cells as compared with MMNK-1 cells. In RBE cells, the process of EGFR sorting for lysosomal degradation was blocked at the early endosome stage, and non-degradated EGFR was recycled to the cell surface. A disrupted association between EGFR and the E3 ubiquitin ligase c-Cbl, as well as hypo-phosphorylation of EGFR at tyrosine 1045 (Tyr1045, were also observed in RBE cells. Conclusion In RBE cells, up-regulation of EGFR Tyr1045 phosphorylation is a potentially useful molecular alteration in EGFR-targeted therapy. The combination of molecular-targeted therapy determined by the characteristics of individual EGFR phosphorylation events and EGFR recycling inhibition show promise in future treatments of cholangiocarcinoma.

  6. Epidermal growth factor-like domain-containing protein 7 (EGFL7 enhances EGF receptor-AKT signaling, epithelial-mesenchymal transition, and metastasis of gastric cancer cells.

    Directory of Open Access Journals (Sweden)

    Bai-Hua Luo

    Full Text Available Epidermal growth factor-like domain-containing protein 7 (EGFL7 is upregulated in human epithelial tumors and so is a potential biomarker for malignancy. Indeed, previous studies have shown that high EGFL7 expression promotes infiltration and metastasis of gastric carcinoma. The epithelial-mesenchymal transition (EMT initiates the metastatic cascade and endows cancer cells with invasive and migratory capacity; however, it is not known if EGFL7 promotes metastasis by triggering EMT. We found that EGFL7 was overexpressed in multiple human gastric cancer (GC cell lines and that overexpression promoted cell invasion and migration as revealed by scratch wound and transwell migration assays. Conversely, shRNA-mediated EGFL7 knockdown reduced invasion and migration. Furthermore, EGFL7-overexpressing cells grew into larger tumors and were more likely to metastasize to the liver compared to underexpressing CG cells following subcutaneous injection in mice. EGFL7 overexpression protected GC cell lines against anoikis, providing a plausible mechanism for this enhanced metastatic capacity. In excised human gastric tumors, expression of EGFL7 was positively correlated with expression levels of the mesenchymal marker vimentin and the EMT-associated transcription repressor Snail, and negatively correlated with expression of the epithelial cell marker E-cadherin. In GC cell lines, EGFL7 knockdown reversed morphological signs of EMT and decreased both vimentin and Snail expression. In addition, EGFL7 overexpression promoted EGF receptor (EGFR and protein kinase B (AKT phospho-activation, effects markedly suppressed by the EGFR tyrosine kinase inhibitor AG1478. Moreover, AG1478 also reduced the elevated invasive and migratory capacity of GC cell lines overexpressing EGFL7. Collectively, these results strongly suggest that EGFL7 promotes metastasis by activating EMT through an EGFR-AKT-Snail signaling pathway. Disruption of EGFL7-EGFR-AKT-Snail signaling may a

  7. Dual silencing of insulin-like growth factor-I receptor and epidermal growth factor receptor in colorectal cancer cells is associated with decreased proliferation and enhanced apoptosis.

    Science.gov (United States)

    Kaulfuss, Silke; Burfeind, Peter; Gaedcke, Jochen; Scharf, Jens-Gerd

    2009-04-01

    Overexpression and activation of tyrosine kinase receptors are common features of colorectal cancer. Using the human colorectal cancer cell lines DLD-1 and Caco-2, we evaluated the role of the insulin-like growth factor-I (IGF-I) receptor (IGF-IR) and epidermal growth factor receptor (EGFR) in cellular functions of these cells. We used the small interfering RNA (siRNA) technology to specifically down-regulate IGF-IR and EGFR expression. Knockdown of IGF-IR and EGFR resulted in inhibition of cell proliferation of DLD-1 and Caco-2 cells. An increased rate of apoptosis was associated with siRNA-mediated silencing of IGF-IR and EGFR as assessed by activation of caspase-3/caspase-7. The combined knockdown of both EGFR and IGF-IR decreased cell proliferation and induced cell apoptosis more effectively than did silencing of either receptor alone. Comparable effects on cell proliferation and apoptosis were observed after single and combinational treatment of cells by the IGF-IR tyrosine kinase inhibitor NVP-AEW541 and/or the EGFR tyrosine kinase inhibitor erlotinib. Combined IGF-IR and EGFR silencing by either siRNAs or tyrosine kinase inhibitors diminished the phosphorylation of downstream signaling pathways AKT and extracellular signal-regulated kinase (ERK)-1/2 more effectively than did the single receptor knockdown. Single IGF-IR knockdown inhibited IGF-I-dependent phosphorylation of AKT but had no effect on IGF-I- or EGF-dependent phosphorylation of ERK1/2, indicating a role of EGFR in ligand-dependent ERK1/2 phosphorylation. The present data show that inhibition of the IGF-IR transduction cascade augments the antipoliferative and proapoptotic effects of EGFR inhibition in colorectal cancer cells. A clinical application of combination therapy targeting both EGFR and IGF-IR could be a promising therapeutic strategy.

  8. Simultaneous screening of four epidermal growth factor receptor antagonists from Curcuma longa via cell membrane chromatography online coupled with HPLC-MS.

    Science.gov (United States)

    Sun, Meng; Ma, Wei-na; Guo, Ying; Hu, Zhi-gang; He, Lang-chong

    2013-07-01

    The epidermal growth factor receptors (EGFRs) are significant targets for screening active compounds. In this work, an analytical method was established for rapid screening, separation, and identification of EGFRs antagonists from Curcuma longa. Human embryonic kidney 293 cells with a steadily high expression of EGFRs were used to prepare the cell membrane stationary phase in a cell membrane chromatography model for screening active compounds. Separation and identification of the retention chromatographic peaks was achieved by HPLC-MS. The active sites, docking extents and inhibitory effects of the active compounds were also demonstrated. The screening result found that ar-turmerone, curcumin, demethoxycurcumin, and bisdemethoxycurcumin from Curcuma longa could be active components in a similar manner to gefitinib. Biological trials showed that all of four compounds can inhibit EGFRs protein secretion and cell growth in a dose-dependent manner, and downregulate the phosphorylation of EGFRs. This analytical method demonstrated fast and effective characteristics for screening, separation and identification of the active compounds from a complex system and should be useful for drug discovery with natural medicinal herbs. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Novel epidermal growth factor receptor pathway mediates release of human β-defensin 3 from Helicobacter pylori-infected gastric epithelial cells.

    Science.gov (United States)

    Muhammad, Jibran S; Zaidi, Syed F; Zhou, Yue; Sakurai, Hiroaki; Sugiyama, Toshiro

    2016-04-01

    Persistent Helicobacter pylori (H. pylori) infection in hostile gastric mucosa can result in gastric diseases. Helicobacter pylori induces to express antimicrobial peptides from gastric epithelial cells, especially human β-defensin 3 (hBD3), as an innate immune response, and this expression of hBD3 is mediated by epidermal growth factor receptor (EGFR) activation. In this study, we found that phosphorylation of a serine residue of EGFR via transforming growth factor β-activated kinase-1 (TAK1), and subsequent p38α activation is essential for H. pylori-induced hBD3 release from gastric epithelial cells. We showed that this pathway was dependent on H. pylori type IV secretion system and was independent of H. pylori-derived CagA or peptidoglycan. H. pylori infection induced phosphorylation of serine residue of EGFR, and this phosphorylation was followed by internalization of EGFR; consequently, hBD3 was released at an early phase of the infection. In the presence of TAK1 or p38α inhibitors, synthesis of hBD3 was completely inhibited. Similar results were observed in EGFR-, TAK1- or p38α-knockdown cells. However, NOD1 knockdown in gastric epithelial cells did not inhibit hBD3 induction. Our study has firstly demonstrated that this novel EGFR activating pathway functioned to induce hBD3 at an early phase of H. pylori infection.

  10. Gefitinib, an epidermal growth factor receptor blockade agent, shows additional or synergistic effects on the radiosensitivity of esophageal cancer cells in vitro.

    Directory of Open Access Journals (Sweden)

    Taira,Naruto

    2006-02-01

    Full Text Available

    Human esophageal cancers have been shown to express high levels of epidermal growth factor receptor (EGFR and a relationship between high EGFR expression and local advance, the number of lymph node metastases, life expectancy, and sensitivity to chemo-radiotherapy has been demonstrated. We examined the use of gefitinib, an orally active EGFR-selective tyrosine kinase inhibitor, as a new strategy for treatment of esophageal carcinoma. The effects of gefitinib were evaluated in monotherapy and in combination with radiotherapy in human esophageal carcinoma cell lines. Gefitinib produced a dose-dependent inhibition of cellular proliferation in all of the 8 esophageal carcinoma cell lines examined, with IC50 values ranging from 5.7 microM to 36.9 microM. In combination, gefitinib and radiotherapy showed a synergistic effect in 2 human esophageal carcinoma cell lines and an additive effect in 5 cell lines. Western blotting demonstrated that gefitinib blocked activation of the EGFR-extracellular signal-regulated kinase (Erk pathway and the EGFR-phosphoinositide-3 kinase (PI3K-Akt pathway after irradiation. These results suggest that further evaluation of EGFR blockade as a treatment for esophageal cancer should be performed, and that radiotherapy combined with EGFR blockade may enhance the response of esophageal carcinoma to therapy.

  11. Lysophosphatidic acid transactivates both c-Met and epidermal growth factor receptor, and induces cyclooxygenase-2 expression in human colon cancer LoVo cells

    Institute of Scientific and Technical Information of China (English)

    Dai Shida; Joji Kitayama; Hironori Yamaguchi; Hiroharu Yamashita; Ken Mori; Toshiaki Watanabe; Hirokazu Nagawa

    2005-01-01

    AIM: To examine whether lysophosphatidic acid (LPA)induces phosphorylation of c-Met and epidermal growth factor receptor (EGFR), both of which have been proposed as prognostic markers of colorectal cancer, and whether LPA induces cyclooxygenase-2 (COX-2) expression in human colon cancer cells.METHODS: Using a human colon cancer cell line, LoVo cells, we performed immunoprecipitation analysis,followed by Western blot analysis. We also examined whether LPA induced COX-2 expression, by Western blot analysis.RESULTS: Immunoprecipitation analysis revealed that 10 μmol/L LPA induced tyrosine phosphorylation of c-Met and EGFR in LoVo cells within a few minutes. We found that c-Met tyrosine phosphorylation induced by LPA was not attenuated by pertussis toxin or a matrix metalloproteinase inhibitor, in marked contrast to the results for EGFR. In addition, 0.2-40 μmol/L LPA induced COX-2 expression in a dose-dependent manner.CONCLUSION: Our results suggest that LPA acts upstream of various receptor tyrosine kinases (RTKs) and COX-2,and thus may act as a potent stimulator of colorectal cancer.

  12. Inhibition of chemomigration of a human prostatic carcinoma cell (TSU-pr1) line by inhibition of epidermal growth factor receptor function.

    Science.gov (United States)

    Zolfaghari, A; Djakiew, D

    1996-04-01

    Chemoattractants expressed at bony sites and pelvic lymph nodes are thought to promote the preferential metastasis of human prostate tumor cells to these organs. Epidermal growth factor (EGF) is a potent chemoattractant for several human metastatic prostate tumor cell lines, including the TSU-pr1 cell line, and EGF has been localized to the stroma of both bony sites and pelvic lymph nodes in humans. Hence, we investigated whether the TSU-pr1 cell line expresses a functional EGF receptor (EGFR), which when antagonized reduces EGF-mediated chemomigration of this cell line. In this context, the EGFR immunoprecipitated from cell lysates of TSU-pr1 cells comigrated with the EGFR from A431 cells at a molecular weight of 170 kD. Addition of human EGF (hEGF) to the TSU-pr1 cells for 5 min stimulated the dose-dependent biphasic phosphorylation of the EGFR, with maximal stimulation of EGFR phosphorylation occurring at 2 ng/ml hEGF. In addition, treatment of hEGF-stimulated (2 ng/ml) TSU-pr1 cells with 0.5 microgram/ml anti-hEGF monoclonal antibody or 100 nM staurosporine inhibited EGFR phosphorylation. Conversely, as negative controls, treatment of hEGF-stimulated (2 ng/ml) TSU-pr1 cells with K252a or dimethyl sulfoxide (DMSO) vehicle did not inhibit EGFR phosphorylation. TSU-pr1 cells were stimulated to migration in 4 hr across Boyden chambers in response to 10 ng/ml hEGF. Treatment of the TSU-pr1 cells with anti-hEGFR monoclonal antibody inhibited in a dose-dependent manner the chemomigration of the TSU-pr1 cells across Boyden chambers. Similarly, treatment of the TSU-pr1 cells with staurosporine inhibited in a dose-dependent manner the chemomigration of the TSU-pr1 cells across Boyden chambers. These results demonstrate that antagonists of hEGF-mediated hEGFR phosphorylation also antagonize chemomigration of the TSU-pr1 cells across Boyden chambers, suggesting that antagonists of the EGFR in prostate cancer may be useful in the treatment of metastatic disease.

  13. Epidermal nevus syndromes.

    Science.gov (United States)

    Asch, Sarah; Sugarman, Jeffrey L

    2015-01-01

    The term epidermal nevus syndrome (ENS) has been used to describe the association of epidermal hamartomas and extracutaneous abnormalities. Although many continue to use the term "ENS," it is now understood that this is not one disease, but rather a heterogeneous group with distinct genetic profiles defined by a common cutaneous phenotype: the presence of epidermal and adnexal hamartomas that are associated with other organ system involvement. One commonality is that epidermal nevi often follow the lines of Blaschko and it appears the more widespread the cutaneous manifestations, the greater the risk for extracutaneous manifestations. The majority of the extracutaneous manifestations involve the brain, eye, and skeletal systems. The CNS involvement is wide ranging and involves both clinical manifestations such as intellectual disability and seizures, as well as structural anomalies. Several subsets of ENS with characteristic features have been delineated including the nevus sebaceus syndrome, Proteus syndrome, CHILD syndrome, Becker's nevus syndrome, nevus comedonicus syndrome, and phakomatosis pigmentokeratotica. Advances in molecular biology have revealed that the manifestations of ENS are due to genomic mosaicism. It is likely that the varied clinical manifestations of ENS are due in great part to the functional effects of specific genetic defects. Optimal management of the patient with ENS involves an interdisciplinary approach given the potential for multisystem involvement. Of note, epidermal nevi have been associated with both benign and malignant neoplasms, and thus ongoing clinical follow-up is required.

  14. Epidermal nevus syndrome.

    Science.gov (United States)

    Laura, Flores-Sarnat

    2013-01-01

    Epidermal nevus syndrome (ENS) is an inclusive term for a heterogeneous group of congenital disorders characterized by the presence of epidermal nevi associated with systemic involvement. These disorders, as are all primary neurocutaneous syndromes, are neurocristopathies. The epidermal nevi that follow the lines of Blaschko and most systemic anomalies in skeletal, ocular, cardiovascular, endocrine, and orodental tissues, as well as lipomas, are due to defective neural crest. The most important and frequent anomaly in the brain in all forms of epidermal nevus syndromes (ENSs) is hemimegalencephaly (HME). This malformation often is not recognized, despite being the principal cause of neurological manifestations in ENSs. They consist mainly of epilepsy and developmental delay or intellectual disability. The onset of epilepsy in ENS usually is in early infancy, often as infantile spasms. Several syndromic forms have been delineated. I propose the term "Heide's syndrome" for those distinctive cases with the typical triad of hemifacial epidermal nevus, ipsilateral facial lipoma, and hemimegalencephaly. Most ENSs are sporadic. The mechanism is thought to be genetic mosaicism with a lethal autosomal dominant gene. Specific genetic mutations (PTEN, FGFR3, PIK3CA, and AKT1) have been documented in some patients. The large number of contributors for over more than a century and a half to the description of these disorders precludes the use of new author eponyms.

  15. Synergistic Induction of Cyclooxygenase-2 by Transforming Growth Factor-β1 and Epidermal Growth Factor Inhibits Apoptosis in Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Debabrata Saha

    1999-12-01

    Full Text Available Increased expression of cyclooxygenase-2 (COX-2 expression has been observed in several human tumor types and in selected animal and cell culture models of carcinogenesis, including lung cancer. Increased expression of COX-2 and production of prostaglandins appear to provide a survival advantage to transformed cells through the inhibition of apoptosis, increased attachment to extracellular matrix, increased invasiveness, the stimulation of angiogenesis. In the present studies, we found that transforming growth factor β1 (TGF-β1 and epidermal growth factor (EGF synergistically induced the expression of COX-2 and prostaglandin E2 (PGE2 production in mink lung epithelial (Mvi Lu cells. EGF, but not PDGF or IGF-1, was able to inhibit TGF-β1-induced apoptosis in Mvi Lu cells and this effect was blocked by NS-398, a selective inhibitor of COX-2 activity, suggesting a possible role for COX-2 in the anti-apoptosic effect of EGF receptor ligands. The combination of TGF-β1 and EGF also significantly induced COX-2 expression in rat intestinal epithelial (RIE-1 cells and completely prevented sodium butyrate (NaBu-induced apoptosis. The synergistic induction of COX-2 by TGF-β1 and EGF was not observed in R1B-L17 cells, a line derived from Mvi Lu cells that lacks the TGF-β type-I receptor. AG1478, a selective inhibitor of EGF receptor tyrosine kinase activity, completely suppressed the induction of COX-2 expression by either EGF or TGF-β1+EGF. Also, PD98059, a specific inhibitor of MEK/ERK pathway, SB203580, a specific inhibitor of p38 MAPK activity, significantly inhibited the induction of COX-2 in response to combined EGF and TGF-β1. These results suggest an important collaborative interaction of TGF-β1 and EGF signaling in the induction of COX-2 and prostaglandin production in Mv1Lu cells.

  16. Canine epidermal neural crest stem cells: characterization and potential as therapy candidate for a large animal model of spinal cord injury.

    Science.gov (United States)

    Gericota, Barbara; Anderson, Joseph S; Mitchell, Gaela; Borjesson, Dori L; Sturges, Beverly K; Nolta, Jan A; Sieber-Blum, Maya

    2014-03-01

    The discovery of multipotent neural crest-derived stem cells, named epidermal neural crest stem cells (EPI-NCSC), that persist postnatally in an easy-to-access location-the bulge of hair follicles-opens a spectrum of novel opportunities for patient-specific therapies. We present a detailed characterization of canine EPI-NCSC (cEPI-NCSC) from multiple dog breeds and protocols for their isolation and ex vivo expansion. Furthermore, we provide novel tools for research in canines, which currently are still scarce. In analogy to human and mouse EPI-NCSC, the neural crest origin of cEPI-NCSC is shown by their expression of the neural crest stem cell molecular signature and other neural crest-characteristic genes. Similar to human EPI-NCSC, cEPI-NCSC also expressed pluripotency genes. We demonstrated that cEPI-NCSC can generate all major neural crest derivatives. In vitro clonal analyses established multipotency and self-renewal ability of cEPI-NCSC, establishing cEPI-NCSC as multipotent somatic stem cells. A critical analysis of the literature on canine spinal cord injury (SCI) showed the need for novel treatments and suggested that cEPI-NCSC represent viable candidates for cell-based therapies in dog SCI, particularly for chondrodystrophic dogs. This notion is supported by the close ontological relationship between neural crest stem cells and spinal cord stem cells. Thus, cEPI-NCSC promise to offer not only a potential treatment for canines but also an attractive and realistic large animal model for human SCI. Taken together, we provide the groundwork for the development of a novel cell-based therapy for a condition with extremely poor prognosis and no available effective treatment.

  17. Role of inositol (1,4,5)trisphosphate in epidermal growth factor-induced Ca2+ signaling in A431 cells

    DEFF Research Database (Denmark)

    Hughes, A R; Bird, G S; Obie, J F;

    1991-01-01

    but significant Ca2+ signal after the addition of bradykinin. Experiments were designed to determine whether the Ca2+ response to epidermal growth factor after bradykinin results from mobilization of Ca2+ by an inositol 1,4,5-trisphosphate-independent mechanism. Epidermal growth factor stimulated additional...

  18. Human amniotic fluid derived cells can competently substitute dermal fibroblasts in a tissue-engineered dermo-epidermal skin analog

    NARCIS (Netherlands)

    Hartmann-Fritsch, Fabienne; Hosper, Nynke; Luginbuehl, Joachim; Biedermann, Thomas; Reichmann, Ernst; Meuli, Martin

    Human amniotic fluid comprises cells with high differentiation capacity, thus representing a potential cell source for skin tissue engineering. In this experimental study, we investigated the ability of human amniotic fluid derived cells to substitute dermal fibroblasts and support epidermis

  19. Epidermal Growth Factor Receptor Kinase Inhibitors Synergize with TCDD to Induce CYP1A1/1A2 in Human Breast Epithelial MCF10A Cells.

    Science.gov (United States)

    Joiakim, Aby; Mathieu, Patricia A; Shelp, Catherine; Boerner, Julie; Reiners, John J

    2016-05-01

    CYP1A1 and CYP1A2 are transcriptionally activated in the human normal breast epithelial cell line MCF10A following exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Shifting MCF10A cultures to medium deficient in serum and epidermal growth factor (EGF) caused rapid reductions in the activated (i.e., phosphorylated) forms of extracellular regulated kinases (ERKs) and the epidermal growth factor receptor (EGFR). Shifting to serum/EGF-deficient medium also enhanced TCDD-mediated induction of cytochrome P450 (CYP)1A1 Treatment of cells cultured in complete medium with the EGFR inhibitors gefitinib (Iressa), AG1478, and CI-1033 resulted in concentration-dependent reductions of active EGFR and ERKs, and increased CYP1A1 mRNA content ∼3- to 18-fold above basal level. EGFR inhibitors synergized with TCDD and resulted in transient CYP1A1 and CYP1A2 mRNA accumulations ∼8-fold greater (maximum at 5 hours) than that achieved with only TCDD. AG1478, gefitinib, and TCDD individually induced small increases (∼1.2- to 2.5-fold) in CYP1A1 protein content but did not cause additive or synergistic accumulations of CYP1A1 protein when used in combination. The mitogen-activated protein kinase kinase inhibitor PD184352 inhibited ERK and EGFR activation in a concentration-dependent fashion without causing CYP1A1 mRNA accumulation. However, cotreatment with PD184352 potentiated TCDD-mediated CYP1A1 induction. TCDD-mediated induction of CYP1A1 in MCF7-TET on-EGFR cells, a MCF7 variant in which EGFR expression can be controlled, was not affected by the activity status of EGFR or ERKs. Hence, EGFR signaling mutes both basal and ligand-induced expression of two aryl hydrocarbon receptor-responsive P450s in MCF10A cultures. However, these effects are cell context-dependent. Furthermore, CYP1A1 mRNA and protein abundance are not closely coupled in MCF10A cultures.

  20. Nimotuzumab enhances radiation sensitivity of NSCLC H292 cells in vitro by blocking epidermal growth factor receptor nuclear translocation and inhibiting radiation-induced DNA damage repair

    Directory of Open Access Journals (Sweden)

    Teng K

    2015-04-01

    Full Text Available Kai Teng,1,2,* Yong Zhang,1,* Xiaoyan Hu,1 Yihui Ding,1 Rui Gong,1 Li Liu1,* 1Department of Thoracic Oncology, Cancer Center of Wuhan Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, People’s Republic of China; 2Department of Radiation Oncology, Hainan Cancer Hospital, Haikou, Hainan, People’s Republic of China *These authors contributed equally to this work Background: The epidermal growth factor receptor (EGFR signaling pathway plays a significant role in radiation resistance. There is evidence that EGFR nuclear translocation is associated with DNA double-strand breaks (DSB repair. Nimotuzumab has shown the effect of radiosensitization in various cancer cells, but little is known about the relationship between nimotuzumab and EGFR nuclear translocation in non-small cell lung cancer (NSCLC cell lines. In this study, we selected two NSCLC cell lines, namely, H292 (with high EGFR expression and H1975 (with low EGFR expression and explored the mechanisms underlying radiation sensitivity.Methods: MTT assay, clonogenic survival assay, and flow cytometry were performed separately to test cell viability, radiation sensitivity, cell cycle distribution, and apoptosis. Protein γ-H2AX, DNA-PK/p-DNA-PK, and EGFR/p-EGFR expression were further compared both in the cytoplasm and the nucleus with the western blot.Results: Nimotuzumab reduced the viability of H292 cells and sensitized H292 cells to ionizing radiation. The radiation sensitivity enhancement ratio (SER was 1.304 and 1.092 for H292 and H1975 cells, respectively. H292 cells after nimotuzumab administration were arrested at the G0/G1 phase in response to radiation. Apoptosis was without statistical significance in both cell lines. γ-H2AX formation in the combination group (nimotuzumab and radiation increased both in the cytoplasm and the nucleus along with the decreased expression of nuclear EGFR/p-EGFR and p-DNA-PK in H292 cells (P<0.05 that

  1. Transforming growth factor-β1 induces EMT by the transactivation of epidermal growth factor signaling through HA/CD44 in lung and breast cancer cells.

    Science.gov (United States)

    Li, Lingmei; Qi, Lisha; Liang, Zhijie; Song, Wangzhao; Liu, Yanxue; Wang, Yalei; Sun, Baocun; Zhang, Bin; Cao, Wenfeng

    2015-07-01

    Epithelial-mesenchymal transition (EMT), a process closely related to tumor development, is regulated by a variety of signaling pathways and growth factors, such as transforming growth factor-β1 (TGF-β1) and epidermal growth factor (EGF). Hyaluronan (HA) has been shown to induce EMT through either TGF-β1 or EGF signaling and to be a regulator of the crosstalk between these two pathways in fibroblasts. In this study, in order to clarify whether HA has the same effect in tumor cells, we utilized the lung cancer cell line, A549, and the breast cancer cell line, MCF-7, and found that the effects of stimulation with TGF-β1 were more potent than those of EGF in regulating the expression of EMT-associated proteins and in enhancing cell migration and invasion. In addition, we observed that TGF-β1 activated EGF receptor (EGFR) and its downstream AKT and extracellular signal-regulated kinase (ERK) pathways. Furthermore, we found that TGF-β1 upregulated the expression of hyaluronan synthases (HAS1, HAS2 and HAS3) and promoted the expression of CD44, a cell surface receptor for HA, which interacts with EGFR, resulting in the activation of the downstream AKT and ERK pathways. Conversely, treatment with 4-methylumbelliferone (4-MU; an inhibitor of HAS) prior to stimulation with TGF-β1, inhibited the expression of CD44 and EGFR, abolished the interaction between CD44 and EGFR. Furthermore, the use of shRNA targeting CD44 impaired the expression of EGFR, deactivated the AKT and ERK pathways, reversed EMT and decreased the migration and invasion ability of cells. In conclusion, our data demonstrate that TGF-β1 induces EMT by the transactivation of EGF signaling through HA/CD44 in lung and breast cancer cells.

  2. Influence of epidermal growth factor (EGF) and hydrocortisone on the co-culture of mature adipocytes and endothelial cells for vascularized adipose tissue engineering.

    Science.gov (United States)

    Huber, Birgit; Czaja, Alina Maria; Kluger, Petra Juliane

    2016-05-01

    The composition of vascularized adipose tissue is still an ongoing challenge as no culture medium is available to supply adipocytes and endothelial cells appropriately. Endothelial cell medium is typically supplemented with epidermal growth factor (EGF) as well as hydrocortisone (HC). The effect of EGF on adipocytes is discussed controversially. Some studies say it inhibits adipocyte differentiation while others reported of improved adipocyte lipogenesis. HC is known to have lipolytic activities, which might result in mature adipocyte dedifferentiation. In this study, we evaluated the influence of EGF and HC on the co-culture of endothelial cells and mature adipocytes regarding their cell morphology and functionality. We showed in mono-culture that high levels of HC promoted dedifferentiation and proliferation of mature adipocytes, whereas EGF seemed to have no negative influence. Endothelial cells kept their typical cobblestone morphology and showed a proliferation rate comparable to the control independent of EGF and HC concentration. In co-culture, HC promoted dedifferentiation of mature adipocytes, which was shown by a higher glycerol release. EGF had no negative impact on adipocyte morphology. No negative impact on endothelial cell morphology and functionality could be seen with reduced EGF and HC supplementation in co-culture with mature adipocytes. Taken together, our results demonstrate that reduced levels of HC are needed for co-culturing mature adipocytes and endothelial cells. In co-culture, EGF had no influence on mature adipocytes. Therefore, for the composition of vascularized adipose tissue constructs, the media with low levels of HC and high or low levels of EGF can be used.

  3. Restoring apoptosis in pancreatic cancer cells by targeting the nuclear factor-kappaB signaling pathway with the anti-epidermal growth factor antibody IMC-C225.

    Science.gov (United States)

    Sclabas, Guido M; Fujioka, Shuichi; Schmidt, Christian; Fan, Zhen; Evans, Douglas B; Chiao, Paul J

    2003-01-01

    We have previously demonstrated that RelA is constitutively activated in the majority of human pancreatic cancers and plays an important role in tumorigenesis and metastasis. The antiapoptotic gene bcl-xl is a downstream target of RelA, and regulation of bcl-xl transcription is mediated directly by the nuclear factor kappaB (NF-kappaB) binding sites present in the upstream promoter element of the bcl-xl gene. In this study we investigated the effects of inhibition of epidermal growth factor receptor (EGFR) signaling pathway with the anti-EGFR monoclonal antibody IMC-C225 on constitutive NF-kappaB activation and regulation of apoptosis-related genes in human pancreatic cancer cells. We found that activation of EGFR can be blocked with the anti-EGFR antibody IMC-C225 in the human pancreatic cancer cell line MDA Panc-28, leading to a marked decrease in constitutive NF-kappaB DNA binding activity. Our data also suggest that downregulation of NF-kappaB DNA binding activity by IMC-C225 leads to a decrease in bcl-xl and bfl-1 expression. Therefore, targeting the NF-kappaB signaling pathway with an anti-EGFR antibody may be one strategy to restore apoptosis in human pancreatic cancer cells, thereby enhancing the effect of chemotherapy and radiation therapy.

  4. Oncogenic K-Ras Signals through Epidermal Growth Factor Receptor and Wild-Type H-Ras to Promote Radiation Survival in Pancreatic and Colorectal Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Keith A. Cengel

    2007-04-01

    Full Text Available Pancreatic and colorectal carcinomas frequently express oncogenic/mutant K-Ras that contributes to both tumorigenesis and clinically observed resistance to radiation treatment. We have previously shown that farnesyltransferase inhibitors (FTI radiosensitize many pancreatic and colorectal cancer cell lines that express oncogenic K-ras at doses that inhibit the prenylation and activation of H-Ras but not K-Ras. In the present study, we have examined the mechanism of FTI-mediated radiosensitization in cell lines that express oncogenic K-Ras and found that wild-type H-Ras is a contributor to radiation survival in tumor cells that express oncogenic K-Ras. In these experiments, inhibiting the expression of oncogenic K-Ras, wild-type H-Ras, or epidermal growth factor receptor (EGFR led to similar levels of radiosensitization as treatment with the FTI tipifarnib. Treatment with the EGFR inhibitor gefitinib led to similar levels of radiosensitization, and the combinations of tipifarnib or gefitinib plus inhibition of K-Ras, H-Ras, or EGFR expression did not provide additional radiosensitization compared with tipifarnib or gefitinib alone. Finally, supplementing culture medium with the EGFR ligand transforming growth factor o was able to reverse the radiosensitizing effect of inhibiting K-ras expression. Taken together, these findings suggest that EGFRactivated H-Ras signaling is initiated by oncogenic K-Ras to promote radiation survival in pancreatic and colorectal cancers.

  5. Oncogenic K-Ras Signals through Epidermal Growth Factor Receptor and Wild-Type H-Ras to Promote Radiation Survival in Pancreatic and Colorectal Carcinoma Cells1

    Science.gov (United States)

    Cengel, Keith A.; Voong, K. Rahn; Chandrasekaran, Sanjay; Maggiorella, Laurence; Brunner, Thomas B.; Stanbridge, Eric; Kao, Gary D.; McKenna, W. Gillies; Bernhard, Eric J.

    2007-01-01

    Pancreatic and colorectal carcinomas frequently express oncogenic/mutant K-Ras that contributes to both tumorigenesis and clinically observed resistance to radiation treatment. We have previously shown that farnesyltransferase inhibitors (FTI) radiosensitize many pancreatic and colorectal cancer cell lines that express oncogenic K-ras at doses that inhibit the prenylation and activation of H-Ras but not K-Ras. In the present study, we have examined the mechanism of FTI-mediated radiosensitization in cell lines that express oncogenic K-Ras and found that wild-type H-Ras is a contributor to radiation survival in tumor cells that express oncogenic K-Ras. In these experiments, inhibiting the expression of oncogenic K-Ras, wild-type H-Ras, or epidermal growth factor receptor (EGFR) led to similar levels of radiosensitization as treatment with the FTI tipifarnib. Treatment with the EGFR inhibitor gefitinib led to similar levels of radiosensitization, and the combinations of tipifarnib or gefitinib plus inhibition of K-Ras, H-Ras, or EGFR expression did not provide additional radiosensitization compared with tipifarnib or gefitinib alone. Finally, supplementing culture medium with the EGFR ligand transforming growth factor α was able to reverse the radiosensitizing effect of inhibiting K-ras expression. Taken together, these findings suggest that EGFR-activated H-Ras signaling is initiated by oncogenic K-Ras to promote radiation survival in pancreatic and colorectal cancers. PMID:17460778

  6. Oncogenic K-Ras signals through epidermal growth factor receptor and wild-type H-Ras to promote radiation survival in pancreatic and colorectal carcinoma cells.

    Science.gov (United States)

    Cengel, Keith A; Voong, K Rahn; Chandrasekaran, Sanjay; Maggiorella, Laurence; Brunner, Thomas B; Stanbridge, Eric; Kao, Gary D; McKenna, W Gillies; Bernhard, Eric J

    2007-04-01

    Pancreatic and colorectal carcinomas frequently express oncogenic/mutant K-Ras that contributes to both tumorigenesis and clinically observed resistance to radiation treatment. We have previously shown that farnesyltransferase inhibitors (FTI) radiosensitize many pancreatic and colorectal cancer cell lines that express oncogenic K-ras at doses that inhibit the prenylation and activation of H-Ras but not K-Ras. In the present study, we have examined the mechanism of FTI-mediated radiosensitization in cell lines that express oncogenic K-Ras and found that wild-type H-Ras is a contributor to radiation survival in tumor cells that express oncogenic K-Ras. In these experiments, inhibiting the expression of oncogenic K-Ras, wild-type H-Ras, or epidermal growth factor receptor (EGFR) led to similar levels of radiosensitization as treatment with the FTI tipifarnib. Treatment with the EGFR inhibitor gefitinib led to similar levels of radiosensitization, and the combinations of tipifarnib or gefitinib plus inhibition of K-Ras, H-Ras, or EGFR expression did not provide additional radiosensitization compared with tipifarnib or gefitinib alone. Finally, supplementing culture medium with the EGFR ligand transforming growth factor alpha was able to reverse the radiosensitizing effect of inhibiting K-ras expression. Taken together, these findings suggest that EGFR-activated H-Ras signaling is initiated by oncogenic K-Ras to promote radiation survival in pancreatic and colorectal cancers.

  7. Genetic analysis of Ras genes in epidermal development and tumorigenesis.

    Science.gov (United States)

    Drosten, Matthias; Lechuga, Carmen G; Barbacid, Mariano

    2013-01-01

    Proliferation and differentiation of epidermal keratinocytes are tightly controlled to ensure proper development and homeostasis of the epidermis. The Ras family of small GTPases has emerged as a central node in the coordination of cell proliferation in the epidermis. Recent genetic evidence from mouse models has revealed that the intensity of Ras signaling modulates the proliferative capacity of epidermal keratinocytes. Interfering with Ras signaling either by combined elimination of the 3 Ras genes from the basal layer of the epidermis or by overexpression of dominant-negative Ras isoforms caused epidermal thinning due to hypoproliferation of keratinocytes. In contrast, overexpression of oncogenic Ras mutants in different epidermal cell layers led to hyperproliferative phenotypes including the development of papillomas and squamous cell carcinomas. Here, we discuss the value of loss- and gain-of-function studies in mouse models to assess the role of Ras signaling in the control of epidermal proliferation.

  8. Genetic analysis of Ras genes in epidermal development and tumorigenesis

    Science.gov (United States)

    Drosten, Matthias; Lechuga, Carmen G; Barbacid, Mariano

    2013-01-01

    Proliferation and differentiation of epidermal keratinocytes are tightly controlled to ensure proper development and homeostasis of the epidermis. The Ras family of small GTPases has emerged as a central node in the coordination of cell proliferation in the epidermis. Recent genetic evidence from mouse models has revealed that the intensity of Ras signaling modulates the proliferative capacity of epidermal keratinocytes. Interfering with Ras signaling either by combined elimination of the 3 Ras genes from the basal layer of the epidermis or by overexpression of dominant-negative Ras isoforms caused epidermal thinning due to hypoproliferation of keratinocytes. In contrast, overexpression of oncogenic Ras mutants in different epidermal cell layers led to hyperproliferative phenotypes including the development of papillomas and squamous cell carcinomas. Here, we discuss the value of loss- and gain-of-function studies in mouse models to assess the role of Ras signaling in the control of epidermal proliferation. PMID:24150175

  9. Relationship between serum carcinoembryonic antigen level and epidermal growth factor receptor mutations with the influence on the prognosis of non-small-cell lung cancer patients

    Directory of Open Access Journals (Sweden)

    Cai ZX

    2016-06-01

    Full Text Available Zuxun Cai Department of Thoracic Surgery, Henan Provincial Chest Hospital, Zhengzhou City, People’s Republic of China Objective: To investigate the relationship between serum carcinoembryonic antigen (CEA level and epidermal growth factor receptor (EGFR gene mutations in non-small-cell lung cancer (NSCLC patients and to analyze the influence of CEA level on postoperative survival time in lung cancer patients. Methods: A total of 296 patients who were treated in Thoracic Surgery Department of Henan Provincial Chest Hospital from September 2011 to September 2013 were recruited. The level of tumor markers, such as CEA, was determined before the surgery, and EGFR gene mutations were detected after surgery. Thereby, the relationship between tumor makers, including CEA, and EGFR mutation and its influence on prognosis could be investigated. Results: Among 296 patients, the positive rate of EGFR gene mutation was 37.84% (112/296; the mutation occurred more frequently in nonsmokers, adenocarcinoma patients, women, and patients aged <60 years (P<0.05. Both tumor markers and chemosensitivity indicators were related to the profile of EGFR mutations. Elevated squamous cell carcinoma and Cyfra21-1 as well as positively expressed ERCC1 were more common in patients with wild-type EGFR (P<0.05, whereas increased CEA level was observed more frequently in patients with EGFR gene mutation (P=0.012. The positive rate of EGFR gene mutations was higher as the serum CEA level increased, that is, the positive rate in patients with serum CEA level <5, 5–20, and >20 µg/L was 39.81%, 45.32%, and 65.47%, respectively (P=0.004. Logistic regression analysis showed that CEA level was an independent factor in predicting EGFR gene mutations, and serum CEA level was also an independent factor in affecting the prognosis of NSCLC patients, as the overall 2-year survival rate was 73.86% in elevated CEA group and 86.43% in normal group (P<0.01. Conclusion: The prognosis of

  10. Epidermal growth factor and phorbol myristate acetate increase expression of the mRNA for cytosolic phospholipase A2 in glomerular mesangial cells.

    Science.gov (United States)

    Maxwell, A P; Goldberg, H J; Tay, A H; Li, Z G; Arbus, G S; Skorecki, K L

    1993-01-01

    We have previously shown that phospholipase A2 (PLA2) activity is rapidly activated by epidermal growth factor (EGF) and phorbol 12-myristate 13-acetate (PMA) in renal mesangial cells and other cell systems in a manner that suggests a covalent modification of the PLA2 enzyme(s). This PLA2 activity is cytosolic (cPLA2) and is distinct from secretory forms of PLA2, which are also stimulated in mesangial cells in response to cytokines and other agonists. However, longer-term regulation of cPLA2 in renal cells may also occur at the level of gene expression. Cultured rat mesangial cells were used as a model system to test the effects of EGF and PMA on the regulation of cPLA2 gene expression. EGF and PMA both produced sustained increases in cPLA2 mRNA levels, with a parallel increase in enzyme activity over time. Inhibition of protein synthesis by cycloheximide increased basal cPLA2 mRNA accumulation in serum-starved mesangial cells, and the combination of EGF and cycloheximide resulted in super-induction of cPLA2 gene expression compared with EGF alone. Actinomycin D treatment entirely abrogated the effect of EGF on cPLA2 mRNA accumulation. These findings suggest that regulation of cPLA2 is achieved by factors controlling gene transcription and possibly mRNA stability, in addition to previously characterized posttranslational modifications. Images Figure 1 Figure 2 PMID:8240289

  11. Epidermal growth factor receptor-targeted ultra-small superparamagnetic iron oxide particles for magnetic resonance molecular imaging of lung cancer cells in vitro

    Institute of Scientific and Technical Information of China (English)

    CHEN Chun-li; HU Guang-yuan; MEI Qi; QIU Hong; LONG Guo-xian; HU Guo-qing

    2012-01-01

    Background Magnetic resonance (MR) molecular imaging can detect abnormalities associated with disease at the level of cell and molecule.The epidermal growth factor receptor (EGFR) plays an important role in the development of lung cancer.This study aimed to explore new MR molecular imaging targeting of the EGFR on lung cancer cells.Methods We attached ultra-small superparamagnetic iron oxide (USPIO) particles to cetuximab (C225) anti-human IgG using the carbodiimide method.We made the molecular MR contrast agents C225-USPIO and IgG-USPIO,the latter as a control reagent,and determined concentrations according to the Fe content.Lung cancer A549 cells were cultured and immunocytochemistry (SP) was used to detect the expression of EGFR on cells.We detected the binding rate of C225-USPIO to A549 cells with immunofluorescence staining and flow cytometry.We cultured A549 cells with C225-USPIO at a Fe concentration of 50 μg/ml and assayed the binding of C225-USPIO after 1 hour with Prussian blue staining and transmission electron microscopy (TEM).We determined the effects on imaging of the contrast agent targeted to cells using a 4.7T MRi.We did scanning on the cells labeled with C225-USPIO,IgG-USPIO,and distilled water,respectively.The scanning sequences included axial T1W1,T2W1.Results Immunocytochemical detection of lung cancer A549 cells found them positive for EGFR expression.Immunofluorescence staining and flow cytometry after cultivation with different concentrations of C225-USPIO showed the binding rate higher than the control.Prussian blue staining and transmission electron microscopy revealed that in the C225-USPIO contrast agent group of cells the particle content of Fe in cytoplasmic vesicles or on surface was more than that in the control group.The 4.7T MR imaging (MRI) scan revealed the T2WI signal in the C225-USPIO group of cells decreased significantly more than in unlabeled cells,but there was no significant difference between the time gradients

  12. The Paired-box protein PAX-3 regulates the choice between lateral and ventral epidermal cell fates in C. elegans.

    Science.gov (United States)

    Thompson, Kenneth W; Joshi, Pradeep; Dymond, Jessica S; Gorrepati, Lakshmi; Smith, Harold E; Krause, Michael W; Eisenmann, David M

    2016-04-15

    The development of the single cell layer skin or hypodermis of Caenorhabditis elegans is an excellent model for understanding cell fate specification and differentiation. Early in C. elegans embryogenesis, six rows of hypodermal cells adopt dorsal, lateral or ventral fates that go on to display distinct behaviors during larval life. Several transcription factors are known that function in specifying these major hypodermal cell fates, but our knowledge of the specification of these cell types is sparse, particularly in the case of the ventral hypodermal cells, which become Vulval Precursor Cells and form the vulval opening in response to extracellular signals. Previously, the gene pvl-4 was identified in a screen for mutants with defects in vulval development. We found by whole genome sequencing that pvl-4 is the Paired-box gene pax-3, which encodes the sole PAX-3 transcription factor homolog in C. elegans. pax-3 mutants show embryonic and larval lethality, and body morphology abnormalities indicative of hypodermal cell defects. We report that pax-3 is expressed in ventral P cells and their descendants during embryogenesis and early larval stages, and that in pax-3 reduction-of-function animals the ventral P cells undergo a cell fate transformation and express several markers of the lateral seam cell fate. Furthermore, forced expression of pax-3 in the lateral hypodermal cells causes them to lose expression of seam cell markers. We propose that pax-3 functions in the ventral hypodermal cells to prevent these cells from adopting the lateral seam cell fate. pax-3 represents the first gene required for specification solely of the ventral hypodermal fate in C. elegans providing insights into cell type diversification. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Desmosomal Molecules In and Out of Adhering Junctions: Normal and Diseased States of Epidermal, Cardiac and Mesenchymally Derived Cells

    Directory of Open Access Journals (Sweden)

    Sebastian Pieperhoff

    2010-01-01

    Full Text Available Current cell biology textbooks mention only two kinds of cell-to-cell adhering junctions coated with the cytoplasmic plaques: the desmosomes (maculae adhaerentes, anchoring intermediate-sized filaments (IFs, and the actin microfilament-anchoring adherens junctions (AJs, including both punctate (puncta adhaerentia and elongate (fasciae adhaerentes structures. In addition, however, a series of other junction types has been identified and characterized which contain desmosomal molecules but do not fit the definition of desmosomes. Of these special cell-cell junctions containing desmosomal glycoproteins or proteins we review the composite junctions (areae compositae connecting the cardiomyocytes of mature mammalian hearts and their importance in relation to human arrhythmogenic cardiomyopathies. We also emphasize the various plakophilin-2-positive plaques in AJs (coniunctiones adhaerentes connecting proliferatively active mesenchymally-derived cells, including interstitial cells of the heart and several soft tissue tumor cell types. Moreover, desmoplakin has also been recognized as a constituent of the plaques of the complexus adhaerentes connecting certain lymphatic endothelial cells. Finally, we emphasize the occurrence of the desmosomal transmembrane glycoprotein, desmoglein Dsg2, out of the context of any junction as dispersed cell surface molecules in certain types of melanoma cells and melanocytes. This broadening of our knowledge on the diversity of AJ structures indicates that it may still be too premature to close the textbook chapters on cell-cell junctions.

  14. Intermittent hypoxia induces the proliferation of rat vascular smooth muscle cell with the increases in epidermal growth factor family and erbB2 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Kyotani, Yoji, E-mail: cd147@naramed-u.ac.jp [Department of Pharmacology, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Department of Pharmacy, Nara Medical University Hospital, Kashihara 634-8522 (Japan); Ota, Hiroyo [Second Department of Internal Medicine, Nara Medical University School of Medicine, Kashihara 634-8522 (Japan); Department of Biochemistry, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Itaya-Hironaka, Asako; Yamauchi, Akiyo; Sakuramoto-Tsuchida, Sumiyo [Department of Biochemistry, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Zhao, Jing; Ozawa, Kentaro; Nagayama, Kosuke; Ito, Satoyasu [Department of Pharmacology, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Takasawa, Shin [Department of Biochemistry, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan); Kimura, Hiroshi [Second Department of Internal Medicine, Nara Medical University School of Medicine, Kashihara 634-8522 (Japan); Uno, Masayuki [Department of Pharmacy, Nara Medical University Hospital, Kashihara 634-8522 (Japan); Yoshizumi, Masanori [Department of Pharmacology, Nara Medical University School of Medicine, Kashihara 634-8521 (Japan)

    2013-11-15

    Obstructive sleep apnea is characterized by intermittent hypoxia (IH), and associated with cardiovascular diseases, such as stroke and heart failure. These cardiovascular diseases have a relation to atherosclerosis marked by the proliferation of vascular smooth muscle cells (VSMCs). In this study, we investigated the influence of IH on cultured rat aortic smooth muscle cell (RASMC). The proliferation of RASMC was significantly increased by IH without changing the level of apoptosis. In order to see what induces RASMC proliferation, we investigated the influence of normoxia (N)-, IH- and sustained hypoxia (SH)-treated cell conditioned media on RASMC proliferation. IH-treated cell conditioned medium significantly increased RASMC proliferation compared with N-treated cell conditioned medium, but SH-treated cell conditioned medium did not. We next investigated the epidermal growth factor (EGF) family as autocrine growth factors. Among the EGF family, we found significant increases in mRNAs for epiregulin (ER), amphiregulin (AR) and neuregulin-1 (NRG1) in IH-treated cells and mature ER in IH-treated cell conditioned medium. We next investigated the changes in erbB family receptors that are receptors for ER, AR and NRG1, and found that erbB2 receptor mRNA and protein expressions were increased by IH, but not by SH. Phosphorylation of erbB2 receptor at Tyr-1248 that mediates intracellular signaling for several physiological effects including cell proliferation was increased by IH, but not by SH. In addition, inhibitor for erbB2 receptor suppressed IH-induced cell proliferation. These results provide the first demonstration that IH induces VSMC proliferation, and suggest that EGF family, such as ER, AR and NRG1, and erbB2 receptor could be involved in the IH-induced VSMC proliferation. - Highlights: ●In vitro system for intermittent hypoxia (IH) and sustained hypoxia (SH). ●IH, but not SH, induces the proliferation of rat vascular smooth muscle cell. ●Epiregulin m

  15. Epidermal growth factor activates telomerase activity by direct binding of Ets-2 to hTERT promoter in lung cancer cells.

    Science.gov (United States)

    Hsu, Chung-Ping; Lee, Li-Wen; Tang, Sheau-Chung; Hsin, I-Lun; Lin, Yu-Wen; Ko, Jiunn-Liang

    2015-07-01

    Growth signals are directly or indirectly involved in telomerase regulation. In this study, we investigated molecular mechanisms of the effect of EGF (epidermal growth factor) on regulating hTERT (human telomerase reverse transcriptase) expression. To elucidate specific transcription factors involved in EGF-stimulated hTERT transcription in A549 and H1299 lung cancer cells, transcription factors drives hTERT promoter activity, such as Myc, Mad, and Ets-2, was evaluated on luciferase reporter assay. The upregulation of hTERT promoter by Ets-2 and Myc were abolished by Mad. Using DAPA (DNA affinity precipitation assay), Ets-2 binding to SNP (T) was stronger than Ets-2 binding to SNP (C) at -245 bp upstream of the transcription start site within the core promoter of hTERT. Ets-2 silence by siRNA decreased hTERT expression at mRNA and protein levels. The regulation of hTERT promoter by EGF/Ets-2 was diminished via the EGFR kinase signal pathway-specific inhibitors AG1478 and Iressa. Inhibitors of Erk and Akt inhibited Ets-2-activated hTERT promoter activity. These data suggested that Ets-2, a genuine cancer-specific transcription factor, is actively involved in EGFR kinase-induced hTERT overexpression pathway in lung cancer cells. Blockage of this pathway may contribute to targeted gene therapy in lung cancer.

  16. Role of epidermal growth factor receptor transactivation in endothelin-1-induced enhanced expression of Gi protein and proliferation in A10 vascular smooth muscle cells.

    Science.gov (United States)

    Gomez Sandoval, Yessica-Haydee; Lévesque, Louis-Olivier; Li, Yuan; Anand-Srivastava, Madhu B

    2013-03-01

    We have recently shown that vasoactive peptides such as angiotensin II (Ang II) and endothelin-1 (ET-1) increase the expression of Gi proteins and the proliferation of A10 vascular smooth muscle cells (VSMC) through mitogen-activated protein (MAP) kinase-phosphoinositide (PI) 3-kinase pathways. This study was intended to examine the implication of epidermal growth factor receptor (EGFR) activation in ET-1-induced enhanced expression of Gi proteins and proliferation of A10 VSMC, and to further investigate the underlying mechanisms responsible for these increases. Cell proliferation was determined by [(3)H]thymidine incorporation and the expression of Gi proteins; extracellular signal-regulated kinases 1 and 2 (ERK1/2) and EGFR phosphorylation was determined by Western blotting. Treatment of A10 VSMC with ET-1 enhanced the expression of Gi proteins, which was attenuated by BQ123 and BQ788, antagonists of ET(A) and ET(B) receptor respectively. In addition, ET-1 enhanced the phosphorylation of EGFR in A10 VSMC, which was restored to the control levels by EGFR inhibitor and ETA and ETB receptor antagonists. Furthermore, ET-1 also augmented the proliferation and ERK1/2 phosphorylation of A10 VSMC, which were restored to the control levels by inhibition of EGFR. These data suggest that ET-1 transactivates EGFR, which, through MAP kinase signaling, may contribute to the enhanced expression of Gi proteins and thus increased proliferation of A10 VSMC.

  17. Analysis of Mutations in Epidermal Growth Factor Receptor Gene in Korean Patients with Non-small Cell Lung Cancer: Summary of a Nationwide Survey

    Directory of Open Access Journals (Sweden)

    Sang Hwa Lee

    2015-11-01

    Full Text Available Background: Analysis of mutations in the epidermal growth factor receptor gene (EGFR is important for predicting response to EGFR tyrosine kinase inhibitors. The overall rate of EGFR mutations in Korean patients is variable. To obtain comprehensive data on the status of EGFR mutations in Korean patients with lung cancer, the Cardiopulmonary Pathology Study Group of the Korean Society of Pathologists initiated a nationwide survey. Methods: We obtained 1,753 reports on EGFR mutations in patients with lung cancer from 15 hospitals between January and December 2009. We compared EGFR mutations with patient age, sex, history of smoking, histologic diagnosis, specimen type, procurement site, tumor cell dissection, and laboratory status. Results: The overall EGFR mutation rate was 34.3% in patients with non-small cell lung cancer (NSCLC and 43.3% in patients with adenocarcinoma. EGFR mutation rate was significantly higher in women, never smokers, patients with adenocarcinoma, and patients who had undergone excisional biopsy. EGFR mutation rates did not differ with respect to patient age or procurement site among patients with NSCLC. Conclusions EGFR mutation rates and statuses were similar to those in published data from other East Asian countries.

  18. Combination effects of epidermal growth factor and glial cell line-derived neurotrophic factor on the in vitro developmental potential of porcine oocytes

    DEFF Research Database (Denmark)

    Valleh, Mehdi Vafaye; Rasmussen, Mikkel Aabech; Hyttel, Poul

    2016-01-01

    of improving this issue, the single and combined effects of epidermal growth factor (EGF) and glial cell line-derived neurotrophic factor (GDNF) on oocyte developmental competence were investigated. Porcine cumulus–oocyte cell complexes (COCs) were matured in serum-free medium supplemented with EGF (0, 10...... or 50 ng/ml) and/or GDNF (0, 10 or 50 ng/ml) for 44 h, and subsequently subjected to fertilization and cultured for 7 days in vitro. The in vitro-formed blastocysts derived from selected growth factor groups (i.e. EGF = 50 ng/ml; GDNF = 50 ng/ml; EGF = 50 ng/ml + GDNF = 50 ng/ml) were also used for m......RNA expression analysis, or were subjected to Hoechst staining. The results showed that the addition of EGF and/or GDNF during oocyte maturation dose dependently enhanced oocyte developmental competence. Compared with the embryos obtained from control or single growth factor-treated oocytes, treatment...

  19. Impact of Cell-surface Antigen Expression on Target Engagement and Function of an Epidermal Growth Factor Receptor × c-MET Bispecific Antibody*

    Science.gov (United States)

    Jarantow, Stephen W.; Bushey, Barbara S.; Pardinas, Jose R.; Boakye, Ken; Lacy, Eilyn R.; Sanders, Renouard; Sepulveda, Manuel A.; Moores, Sheri L.; Chiu, Mark L.

    2015-01-01

    The efficacy of engaging multiple drug targets using bispecific antibodies (BsAbs) is affected by the relative cell-surface protein levels of the respective targets. In this work, the receptor density values were correlated to the in vitro activity of a BsAb (JNJ-61186372) targeting epidermal growth factor receptor (EGFR) and hepatocyte growth factor receptor (c-MET). Simultaneous binding of the BsAb to both receptors was confirmed in vitro. By using controlled Fab-arm exchange, a set of BsAbs targeting EGFR and c-MET was generated to establish an accurate receptor quantitation of a panel of lung and gastric cancer cell lines expressing heterogeneous levels of EGFR and c-MET. EGFR and c-MET receptor density levels were correlated to the respective gene expression levels as well as to the respective receptor phosphorylation inhibition values. We observed a bias in BsAb binding toward the more highly expressed of the two receptors, EGFR or c-MET, which resulted in the enhanced in vitro potency of JNJ-61186372 against the less highly expressed target. On the basis of these observations, we propose an avidity model of how JNJ-61186372 engages EGFR and c-MET with potentially broad implications for bispecific drug efficacy and design. PMID:26260789

  20. Impact of Cell-surface Antigen Expression on Target Engagement and Function of an Epidermal Growth Factor Receptor × c-MET Bispecific Antibody.

    Science.gov (United States)

    Jarantow, Stephen W; Bushey, Barbara S; Pardinas, Jose R; Boakye, Ken; Lacy, Eilyn R; Sanders, Renouard; Sepulveda, Manuel A; Moores, Sheri L; Chiu, Mark L

    2015-10-09

    The efficacy of engaging multiple drug targets using bispecific antibodies (BsAbs) is affected by the relative cell-surface protein levels of the respective targets. In this work, the receptor density values were correlated to the in vitro activity of a BsAb (JNJ-61186372) targeting epidermal growth factor receptor (EGFR) and hepatocyte growth factor receptor (c-MET). Simultaneous binding of the BsAb to both receptors was confirmed in vitro. By using controlled Fab-arm exchange, a set of BsAbs targeting EGFR and c-MET was generated to establish an accurate receptor quantitation of a panel of lung and gastric cancer cell lines expressing heterogeneous levels of EGFR and c-MET. EGFR and c-MET receptor density levels were correlated to the respective gene expression levels as well as to the respective receptor phosphorylation inhibition values. We observed a bias in BsAb binding toward the more highly expressed of the two receptors, EGFR or c-MET, which resulted in the enhanced in vitro potency of JNJ-61186372 against the less highly expressed target. On the basis of these observations, we propose an avidity model of how JNJ-61186372 engages EGFR and c-MET with potentially broad implications for bispecific drug efficacy and design.

  1. Efficient proliferation and maturation of fetal liver cells in three-dimensional culture by stimulation of oncostatin M, epidermal growth factor, and dimethyl sulfoxide.

    Science.gov (United States)

    Koyama, Toshie; Ehashi, Tomo; Ohshima, Norio; Miyoshi, Hirotoshi

    2009-05-01

    For the purpose of applying fetal liver cells (FLCs) as a cell source to tissue-engineered bioartificial livers, three-dimensional (3-D) cultures of FLCs using a porous polymer scaffold, as well as monolayer cultures as a control, were simultaneously performed. To achieve efficient growth and differentiation, the FLCs were cultured in the growth medium for the first 3 weeks and then cultured in the differentiation medium for 3 more weeks. In these cultures, stimulating factors (oncostatin M (OSM), epidermal growth factor (EGF), hepatocyte growth factor (HGF), or dimethyl sulfoxide (DMSO)) were added to the media, and their effects were examined. When the growth medium containing OSM and EGF was used, EGF stimulated the growth of FLCs synergistically with OSM. For the differentiation of FLCs into mature hepatocytes, DMSO added to the differentiation medium remarkably enhanced albumin secretion in the 3-D and monolayer cultures, although HGF was effective only in the monolayer culture. Microscopic observation proved that FLCs exhibited hepatocyte-like morphology only in the media containing DMSO. In conclusion, successive supply of the growth medium containing EGF and OSM and the differentiation medium containing DMSO efficiently induced the growth of the 3-D cultured FLCs and their differentiation into mature hepatocytes.

  2. Human amniotic fluid derived cells can competently substitute dermal fibroblasts in a tissue-engineered dermo-epidermal skin analog

    NARCIS (Netherlands)

    Hartmann-Fritsch, Fabienne; Hosper, Nynke; Luginbuehl, Joachim; Biedermann, Thomas; Reichmann, Ernst; Meuli, Martin

    2013-01-01

    Human amniotic fluid comprises cells with high differentiation capacity, thus representing a potential cell source for skin tissue engineering. In this experimental study, we investigated the ability of human amniotic fluid derived cells to substitute dermal fibroblasts and support epidermis formati

  3. Anti-epidermal growth factor receptor siRNA carried by chitosan-transacylated lipid nanocapsules increases sensitivity of glioblastoma cells to temozolomide

    Directory of Open Access Journals (Sweden)

    Messaoudi K

    2014-03-01

    Full Text Available Khaled Messaoudi,1 Patrick Saulnier,1 Kim Boesen,1 Jean-Pierre Benoit,1,2 Frederic Lagarce1,21L'Université Nantes Angers Le Mans, INSERM U1066, Micro et nanomédecines biomimétiques, Angers, France; 2Pharmacy Department, Angers University Hospital, Angers, FranceAbstract: Epidermal growth factor receptor (EGFR is a crucial protein that plays an important role in the maintenance and development of glioblastomas. The silencing or knockdown of EGFR is possible by administering a small interfering ribonucleic acid (siRNA. Lipid nanocapsules (LNCs covered by chitosan were developed in our laboratory by a transacylation process. The resulting nanocapsules have a positive zeta potential that enables electrostatic interactions with the negatively-charged siRNA. Prior to transfection, the cytotoxicity of the nanocapsules by (3-(4,5-dimethylthiazol-2-yl-5-(3-carboxymethoxyphenyl-2-(4-sulfophenyl-2H-tetrazolium (MTS test was performed on the U87MG cell line to determine non-toxic levels of the LNCs to avoid cell mortality. Treatment of the U87MG cells with the chitosan-transacylated LNCs/anti-EGFR siRNA complex resulted in a reduction of EGFR expression by 51.95%±6.03% (P≤0.05 after 96 hours of incubation. It also increased the cellular sensitivity to temozolomide in comparison to untreated cells with siRNA. The largest increase in mortality was 62.55%±3.55% (P<0.05. This successful knockdown provides proof for the concept of surface grafting of siRNA onto LNCs to modify cell sensitivity to temozolomide. The method could be implemented in future clinical models regarding the experimental treatment of glioblastoma cancer.Keywords: EGFR, glioblastoma, siRNA, lipid nanocapsules, chitosan, temozolomide

  4. Death ligand TRAIL, secreted by CD1a+ and CD14+ cells in blister fluids, is involved in killing keratinocytes in toxic epidermal necrolysis.

    Science.gov (United States)

    de Araujo, Elisabeth; Dessirier, Valérie; Laprée, Geneviève; Valeyrie-Allanore, Laurence; Ortonne, Nicolas; Stathopoulos, Efstathios N; Bagot, Martine; Bensussan, Armand; Mockenhaupt, Maja; Roujeau, Jean-Claude; Tsapis, Andreas

    2011-02-01

    Toxic epidermal necrolysis (TEN) is characterized by an acute detachment and destruction of keratinocytes, affecting large areas of the skin. It is often related to adverse drug reactions. Previous studies have shown that effector CD8+ T cells, which accumulate in the blister fluid, are functionally cytotoxic and act through a classical perforin/granzyme B pathway. It has recently been shown that these cytotoxic T cells also secrete granulysin peptide, which is lethal to keratinocytes. These cytotoxic T cells exert their killer activity against autologous keratinocytes in the presence of the drug. However, they are unlikely to be the only effectors of TEN. We therefore searched for soluble death factors in the blister fluids that might kill keratinocytes. We found that the amounts of interferon-γ, TRAIL and TNF-α proteins were significantly greater in TEN blister fluids than in all controls (normal sera, TEN sera, burns and Eosinophilic pustular folliculitis blister fluids) and TNF-like weak inducer of apoptosis (TWEAK) amounts are also greater in all controls except burns. We showed that these proteins acted in synergy to induce the death of keratinocytes in vitro. We also found that TRAIL and TWEAK were secreted by CD1a+ and CD14+ cells present in the blister fluids. Thus, in addition to MHC class I-restricted cytotoxic T lymphocytes (CTLs), which lyse keratinocytes, ligands secreted by non-lymphoid cells capable of inducing keratinocyte death in an MHC class I-independent manner, also seem to be present in the blister fluids of patients with TEN. © 2011 John Wiley & Sons A/S.

  5. Penile Epidermal Inclusion Cyst

    Directory of Open Access Journals (Sweden)

    M. El-Shazly

    2012-01-01

    Full Text Available We report a case of epidermal inclusion cyst in a 32-year-old male. This was a complication of circumcision that was neglected over years to form stones and urethrocutaneous fistula. Complete excision of the cyst and repair of the fistula were performed successfully. Histopathological examination confirmed our diagnosis.

  6. Effects of icotinib on early-stage non-small-cell lung cancer as neoadjuvant treatment with different epidermal growth factor receptor phenotypes

    Directory of Open Access Journals (Sweden)

    Wang T

    2016-03-01

    Full Text Available Tao Wang,1 Yang Liu,1 Bin Zhou,1 Zhi Wang,1 Naichao Liang,1 Yundong Zhang,1 Zhouhuan Dong,2 Jie Li2 1Department of Thoracic Surgery, 2Department of Pathology, People’s Liberation Army General Hospital, Beijing, People’s Republic of China Purpose: Epidermal growth factor receptor–tyrosine kinase inhibitors (EGFR–TKIs have demonstrated efficacy in treating advanced non-small-cell lung cancer (NSCLC. Preliminary findings suggested that EGFR–TKIs might also be beneficial in neoadjuvant therapy in treating NSCLC. Therefore, this study aimed to evaluate the efficacy and safety of neoadjuvant therapy with icotinib in patients with early-stage NSCLC.Patients and methods: We retrospectively reviewed the medical history of patients who were initially diagnosed with stage IA–IIIA NSCLC and were under icotinib administration before surgery between December 2011 and December 2014. Tumor assessment was conducted between the second and fourth week from initial icotinib treatment. The association between personal characteristics, smoking status, disease stage, EGFR mutation status, and clinical outcomes were investigated using multivariate logistic regression analysis.Results: A total of 67 patients with NSCLC were reviewed, and approximately half (38/67 of them were identified as having EGFR-mutant tumors. The overall response rate of all patients was 26.7% at 2–4 weeks’ assessment. Multivariate analysis showed that female sex (38.5% versus 10.7% in males, P=0.028 and EGFR mutation status (42.1% versus 6.9% in EGFR wild type, P=0.011 were independent predictive factors. The analysis also showed that the most common adverse effects were rash (43.3% and dry skin (34.4%, which were tolerable.Conclusion: Icotinib induced clinical response with minimal toxicity as neoadjuvant treatment in early NSCLC, especially in patients with common EGFR mutations. Further studies are warranted to confirm our findings. Keywords: non-small-cell lung cancer

  7. 中国28种卫矛属植物叶表皮细胞的电镜扫描观察%Observation of Leaf Epidermal Cells of 28 Species of Euonymus in China by Electron Microscope Scanning

    Institute of Scientific and Technical Information of China (English)

    郑彦超; 明晓; 涂蔷; 吴璇; 王若涵

    2012-01-01

    The leaf epidermal cells of 28 species of Euonymus in China were observed by scanning electron microscopy (SEM), and the observed objects contain cell boundary, shape of cells, pattern of anticlinal wall and cuticular membrane morphology. The results revealed that there were various types exist in the leaf epidermal cells of Euonymus. Adaxial and abaxial epidermal cells are different among 13 species such as E. vihumoides and E. chuii. The classical taxonomic treatment as five sections of Euonymus is not supported by this research. Affinilive species usually possess same type on the leaf epidermal cells. E. mengzeanus and E. hystrix were supported as independent specie.%使用扫描电子显微镜对中国28种卫矛属植物的叶表皮细胞进行观察,观察对象包括细胞界限、细胞形状、垂周壁样式、角质膜形态.结果表明,叶表皮细胞形态特征在属内存在多种类型,荚迷卫矛、隐刺卫矛等13种的叶上、下表皮细胞形态具有差别,不支持经典分类学中属下5个组的划分,亲缘关系相近的种通常具有同类型的叶表皮细胞形态特征,支持蒙自卫矛、刺猬卫矛作为独立的种存在.

  8. Ethical and policy issues surrounding the donation of cryopreserved and fresh embryos for human embryonic stem cell research.

    Science.gov (United States)

    Cohen, Cynthia B

    2009-06-01

    The use of human embryos in human embryonic stem cell (hESC) research raises significant ethical and policy issues associated with their donation. Recent research conducted in several countries assesses the percent of persons with cryopreserved and fresh supernumerary embryos willing to donate them for research, their reasons for considering this option, and the concerns they raise about its personal import. Such research provides new insights into rising ethical and policy questions associated with embryo donation for hESC research that should be addressed. In response to such questions, it is argued here that consent to the donation of supernumerary embryos for hESC research should be sought in two or three stages, depending on whether fresh or frozen embryos are at issue, in order to provide patients and their partners with sufficient time and information before they make a final decision. In addition, steps should be taken to support the voluntariness of their decisions by having personnel other than the treating reproductive specialist or stem cell investigators solicit their consent. Prospective embryo donors should also be given a choice about the uses to which hESCs derived from their donated embryos will be put in order to honor their ethical convictions and ensure that there are sufficient embryos for this research. The well-being and rights of those who donate embryos for this research require the sort of support and protection that can be provided by an ethical and policy framework that allows hESC investigations to move forward according to standards that are transparent and that resound with public values.

  9. [Beyond immunopathogenesis. Insulin resistance and "epidermal dysfunction"].

    Science.gov (United States)

    Boehncke, W-H; Boehncke, S; Buerger, C

    2012-03-01

    Insulin is a central player in the regulation of metabolic as well as non-metabolic cells: inefficient signal transduction (insulin resistance) not only represents the cornerstone in the pathogenesis of type 2 diabetes mellitus, but also drives atherosclerosis through inducing endothelial dysfunction. Last but not least epidermal homeostasis depends on insulin. We summarize the effects of insulin on proliferation and differentiation of human keratinocytes as well as the relevance of cytokine-induced insulin resistance for alterations in epidermal homeostasis characteristic for psoriasis. Kinases involved in both insulin- as well as cytokine-receptor signaling represent potential targets for innovative therapeutics. Such small molecules would primarily normalize "epidermal dysfunction", thus complementing the immunomodulatory strategies of today's biologics.

  10. Decreased expression of the plasminogen activator inhibitor type 1 is involved in degradation of extracellular matrix surrounding cervical cancer stem cells.

    Science.gov (United States)

    Sato, Masakazu; Kawana, Kei; Adachi, Katsuyuki; Fujimoto, Asaha; Yoshida, Mitsuyo; Nakamura, Hiroe; Nishida, Haruka; Inoue, Tomoko; Taguchi, Ayumi; Takahashi, Juri; Kojima, Satoko; Yamashita, Aki; Tomio, Kensuke; Nagamatsu, Takeshi; Wada-Hiraike, Osamu; Oda, Katsutoshi; Osuga, Yutaka; Fujii, Tomoyuki

    2016-02-01

    The plasminogen activator (PA) system consists of plasminogen activator inhibitor type 1 (PAI-1), urokinase-type plasminogen activator and its receptor (uPA and uPAR). PAI-1 inhibits the activation of uPA (which converts plasminogen to plasmin), and is involved in cancer invasion and metastasis, by remodeling the extracellular matrix (ECM) through regulating plasmin. Cancer stem cells (CSCs) are a small subset of cells within tumors, and are thought to be involved in tumor recurrence and metastasis. Considering these facts, we investigated the relationship between PAI-1 and cervical CSCs. We used ALDH1 as a marker of cervical CSCs. First, we demonstrated that culturing ALDH1-high cells and ALDH-low cells on collagen IV-coted plates increased their expression of active PAI-1 (ELISA), and these increases were suggested to be at mRNA expression levels (RT-qPCR). Secondly, we demonstrated PAI-1 was indeed involved in the ECM maintenance. With gelatin zymography assays, we found that ALDH1-high cells and ALDH-low cells expressed pro-matrix metalloproteinase-2 (pro-MMP-2) irrespective of their coatings. With gelatinase/collagenase assay kit, we confirmed that collagenase activity was increased when ALDH1-low cells were exposed to TM5275, a small molecule inhibitor of PAI-1. Putting the data together, we hypothesized that cancer cells adhered to basal membrane secrete abundant PAI-1, on the other hand, cancer cells (especially CSCs rather than non-CSCs) distant from basal membrane secrete less PAI-1, which makes the ECM surrounding CSCs more susceptible to degradation. Our study could be an explanation of conflicting reports, where some researchers found negative impacts of PAI-1 expression on clinical outcomes and others not, by considering the concept of CSCs.

  11. Fine structure of the epidermal Leydig cells in the axolotl Ambystoma mexicanum in relation to their function.

    Science.gov (United States)

    Jarial, M S

    1989-12-01

    The fine structure of the Leydig cells in the epidermis of the strictly aquatic adult axolotl Ambystoma mexicanum resembles that of similar cells in larval salamanders. The major finding of this study is that the mucous secretion of the Leydig cells is released into the intercellular spaces from which it is discharged through pores onto the surface of the epidermis where it forms a mucous layer to protect the skin.

  12. Assessment of epidermal growth factor receptor and K-ras mutation status in cytological stained smears of non-small cell lung cancer patients: correlation with clinical outcomes.

    Science.gov (United States)

    Lozano, Maria D; Zulueta, Javier J; Echeveste, Jose I; Gúrpide, Alfonso; Seijo, Luis M; Martín-Algarra, Salvador; Del Barrio, Anabel; Pio, Ruben; Idoate, Miguel Angel; Labiano, Tania; Perez-Gracia, Jose Luis

    2011-01-01

    Epidermal growth factor receptor (EGFR) and K-ras mutations guide treatment selection