Sample records for keratinocyte growth factor

  1. Keratinocyte growth factor

    Microsoft Academic Search

    Jeffrey S. Rubin; Donald P. Bottaro; Marcio Chedid; Toru Miki; Dina Ron; Hyae-Gyeong Cheon; William G. Taylor; Emma Fortney; Hiromi Sakata; Paul W. Finch; William J. LaRochelle

    1995-01-01

    Keratinocyte growth factor (KGF) is a member of the heparin-binding fibroblast growth factor family (FGF-7) with a distinctive pattern of target-cell specificity. Studies performed in cell culture suggested that KGF was mitogenically active only on epithelial cells, albeit from a variety of tissues. In contrast, KGF was produced solely by cells of mesenchymal origin, leading to the hypothesis that it

  2. Expression and Function of Nerve Growth Factor and Nerve Growth Factor Receptor on Cultured Keratinocytes

    Microsoft Academic Search

    Carlo Pincelli; Cinzia Sevignani; Rossella Manfredini; Alexis Grande; Fabrizio Fantini; Luisa Bracci-Laudiero; Luigi Aloe; Sergio Ferrari; Andrea Cossarizza; Alberto Giannetti

    1994-01-01

    Keratinocytes, a key cellular component both for homeostasis and pathophysiologic processes of the skin, secrete a number of cytokines and are stimulated by several growth factors. Nerve growth factor (NGF) is synthesized in the skin and basal keratinocytes express the low-affinity nerve growth factor receptor (NGF-R). We present evidence that normal human keratinocytes in culture express the low- and the

  3. Keratinocyte growth factor (KGF) is required for postnatal thymic regeneration

    Microsoft Academic Search

    Onder Alpdogan; Vanessa M. Hubbard; Odette M. Smith; Neel Patel; Sydney Lu; Gabrielle L. Goldberg; Daniel H. Gray; Jared Feinman; Adam A. Kochman; Jeffrey M. Eng; David Suh; Stephanie J. Muriglan; Richard L. Boyd

    2006-01-01

    Keratinocyte growth factor (KGF) is a member of the fibroblast growth factor family that mediates epithelial cell prolif- eration and differentiation in a variety of tissues, including the thymus. We stud- ied the role of KGF in T-cell development with KGF\\/ mice and demonstrated that thymic cellularity and the distribution of thymocyte subsets among KGF\\/, wild- type (WT), and KGF\\/

  4. The Roles of Growth Factors in Keratinocyte Migration

    PubMed Central

    Seeger, Mark A.; Paller, Amy S.

    2015-01-01

    Significance: The re-epithelialization of wounded skin requires the rapid and coordinated migration of keratinocytes (KC) into the wound bed. Almost immediately after wounding, cells present at or attracted to the wound site begin to secrete a complex milieu of growth factors. These growth factors exert mitogenic and motogenic effects on KCs, inducing the rapid proliferation and migration of KCs at the wound edge. Recent Advances: New roles for growth factors in KC biology are currently being discovered and investigated. This review will highlight the growth factors, particularly transforming growth factor-? (TGF-?), heparin-binding epidermal growth factor (HB-EGF), insulin-like growth factor 1 (IGF-1), fibroblast growth factor 7 (FGF-7), FGF-10, and hepatocyte growth factor (HGF), which have conclusively been shown to be the most motogenic for KCs. Critical Issues: The cellular and molecular heterogeneity of wounded tissue makes establishing direct relationships between specific growth factors and KC migration difficult in situ. The absence of this complexity in simplified in vitro experimental models of migration makes the clinical relevance of the results obtained from these in vitro studies ambiguous. Future Directions: Deciphering the relationship between growth factors and KC migration is critical for understanding the process of wound healing in normal and disease states. Insights into the basic science of the effects of growth factors on KC migration will hopefully lead to the development of new therapies to treat acute and chronic wounds. PMID:25945284

  5. Inhibitory Effects of Retinoids on Vascular Endothelial Growth Factor Production by Cultured Human Skin Keratinocytes

    Microsoft Academic Search

    S. Lachgar; M. Charvéron; Y. Gall; J. L. Bonafé

    1999-01-01

    Background: Vascular endothelial growth factor (VEGF), a potent angiogenic factor and vasodilator, is strongly expressed by epidermal keratinocytes in many angiogenesis-dependent skin disorders. Retinoids may modulate VEGF in skin and this may be related to an effect on rosacea. Aim: To investigate the effect of retinaldehyde on VEGF production by human keratinocytes. Methods: The effects of different concentrations of retinoids

  6. Intranuclear Localization of Insulin-Like Growth Factor Binding Protein3 (IGFBP-3) During Cell Division in Human Keratinocytes

    Microsoft Academic Search

    Christopher J. Wraight; Ingrid J. Liepe; Paul J. White; Alan R. Hibbs; George A. Werther

    1998-01-01

    Insulin-like growth factor-I (IGF-I) stimulation of basal keratinocytes is an essential component of normal epidermal homeostasis. In addition to the IGF receptor, basal keratinocytes synthesize insulin-like growth factor binding protein-3 (IGFBP-3). The HaCaT keratinocyte cell line, which has many characteristics of basal keratinocytes, synthesizes IGFBP-3 that in vitro reduces its IGF-I responsiveness. IGFBP-3 has attracted interest as a potential growth

  7. Basic fibroblast growth factor from human keratinocytes is a natural mitogen for melanocytes

    Microsoft Academic Search

    R. Halaban; R. Langdon; N. Birchall; C. Cuono; A. Baird; G. Scott; G. Moellmann; J. McGuire

    1988-01-01

    To survive and proliferate in pure culture, human melanocytes require basic fibroblast growth factor (bFGF) and cAMP. Without these factors, even in the presence of serum, the cells die. Melanocytes cultured in the presence of keratinocytes, however, sur- vive for weeks without added bFGF and cAMP. We show here that the growth factor for melanocytes pro- duced by human keratinocytes

  8. Keratinocyte growth factor is highly overexpressed in inflammatory bowel disease.

    PubMed Central

    Brauchle, M.; Madlener, M.; Wagner, A. D.; Angermeyer, K.; Lauer, U.; Hofschneider, P. H.; Gregor, M.; Werner, S.

    1996-01-01

    Recently we demonstrated an important function of keratinocyte growth factor (KGF) in wound re-epithelialization. As KGF is mitogenic for various epithelial cells, we speculated about a role of KGF in epithelial repair processes of other organs as seen in a variety of inflammatory diseases. Here we demonstrate a strikingly increased expression of KGF in surgical specimens from patients suffering from Crohn's disease and ulcerative colitis. The levels of KGF expression strongly correlated with the degree of inflammation as assessed by histological analysis of adjacent tissue and expression analysis of the pro-inflammatory cytokine interleukin-1 beta. The highest levels of KGF mRNA and protein were found in mesenchymal cells of the lamina propria, particularly in highly inflamed areas. As the KGF receptor is expressed in intestinal epithelial cells, KGF seems to act in a paracrine manner to stimulate proliferation of these cells. These data suggest a crucial role of KGF in epithelial repair after injury caused by inflammatory processes. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:8701991

  9. Insulin-like growth factor-I and UVB photoprotection in human keratinocytes.

    PubMed

    Fernandez, Tara Lyn; Van Lonkhuyzen, Derek R; Dawson, Rebecca A; Kimlin, Michael G; Upton, Zee

    2015-03-01

    Ultraviolet radiation (UVR), in particular the UVB spectrum, is a risk factor for skin cancer development. The generation and accumulation of UVB-induced genetic mutations are fundamental premalignant events. Keratinocyte interactions between other cutaneous cell populations and the surrounding microenvironment determine cell fate and acute photoresponses. In this study, the importance of the insulin-like growth factor (IGF) system, in particular the insulin-like growth factor-I (IGF-I), on influencing key processes in the keratinocyte acute photoresponse was investigated. Exogenous IGF-I and other growth factors present in dermal fibroblast-conditioned media (CM) were found to significantly enhance keratinocyte survival following UVB irradiation in vitro. This pretreatment was also shown to cause a shift in the expression levels of various DNA damage response proteins. Consequently, this was associated with accelerated rates of UVB-induced cyclobutane pyrimidine dimer removal in these samples. Finally, activation of the IGF system influenced cell cycle progression in UVB-irradiated keratinocytes. Taken together, these results highlight the importance of the IGF signalling network in initiating the repair of potentially mutagenic DNA damage in human keratinocytes. The dysregulation of these processes may therefore have significant implications in the aetiology of skin cancers and other cutaneous diseases. PMID:25607472

  10. Effects of growth factors on the proliferation of human keratinocytes and fibroblasts in vitro.

    PubMed

    Kim, D S; Korting, H C; Schäfer-Korting, M

    1998-01-01

    Growth/differentiation factor-5 (GDF-5) is a new member of the transforming growth factor-beta (TGF-beta) superfamily of multifunctional peptide growth factors that appear to mediate many key events in cell growth and development. The effects of GDF-5 and other growth factors (epidermal growth factor, EGF; TGF-beta 1) on the proliferation of human keratinocytes and fibroblasts compared with desoximetasone and calcipotriol have been investigated. The proliferation rate was determined by a hemocytometer, MTT assay and the incorporation of [3H]-thymidine. Moreover, cell cycle analyses were performed and the influence on interleukin-1 alpha (IL-1 alpha) production in keratinocytes was measured by enzyme-linked immunosorbent assay (ELISA) because of its pronounced proinflammatory effect. In keratinocytes, GDF-5 stimulated cell proliferation to a minor extent. The drug already proved to be effective at very low concentrations (0.1 ng/ml). Growth stimulatory effects with EGF have been observed only in keratinocyte basal medium (KBM), but not in keratinocyte growth medium (KGM). TGF-beta 1 markedly inhibited the proliferation of keratinocytes at concentrations > 1 ng/ml. Calcipotriol and desoximetasone also showed a dose-dependent cell growth inhibition in epidermal cell cultures. IL-1 alpha synthesis was greatly suppressed by calcipotriol 10(-8)-10(-6) M. EGF at 10 ng/ml, in contrast, strongly stimulated IL-1 alpha production. Neither GDF-5 nor TGF-beta 1 had a significant effect on IL-1 alpha production in keratinocyte monolayer cultures. In fibroblasts, GDF-5 induced very weak antiproliferative effects. Calcipotriol and desoximetasone also inhibited cell growth in fibroblast cultures whereas proliferation and DNA synthesis were strongly stimulated by 1 ng/ml EGF. There was, however, a contradiction between TGF-beta 1 results on fibroblasts. Whereas TGF-beta 1 increased proliferation in cell number determination and in the thymidine incorporation assay, MTT assays showed slight antiproliferative effects. Due to these controversial results, in addition cell cycle analysis was employed. TGF-beta 1 led to an increased S phase, which indicates a stimulation of cell division. The different results obtained with the MTT test suggest that TGF-beta 1 may stimulate cell division of fibroblasts not only by increasing the S phase, but also by shortening the G1 phase of the cell cycle. PMID:9476258

  11. Keratinocyte response to immobilized growth factors for enhanced dermal wound healing

    NASA Astrophysics Data System (ADS)

    Stefonek-Puccinelli, Tracy Jane

    Chronic wounds cost billions of dollars per year to treat and wound care is limited to ineffective and/or expensive options. Chronic wounds are characterized by a failure to reepithelialize, as well as deficiencies in growth factors, such as epidermal growth factor (EGF) and insulin-like growth factor-1 (IGF-1), normally present during wound healing. Our system described herein begins to tackle the problems associated with designing bioactive materials for chronic wound healing applications. We show that we can induce accelerated keratinocyte migration with photo-immobilized EGF and further control migration speed through the culture of cells on different types of gradient patterns of EGF. We also successfully immobilized IGF-1 while retaining its bioactivity, and further showed it induces directed keratinocyte migration, although not as potently as immobilized EGF. Potential synergy between co-immobilized IGF-1 and EGF was also investigated, although EGF continued to dominate the cellular response, and no significant increase in cell migration was achieved via the addition of IGF-1 to the system. To further understand cellular response to our immobilized growth factors, we investigated keratinocyte signaling and function in response to changes in EGF presentation. It was found that immobilized and soluble EGF can play different, yet complementary, roles in regulating keratinocyte function. Specifically, keratinocytes responded to immobilized EGF with high EGF receptor (EGFR) activation, accompanied by low proliferation and high migratory activity. In contrast, keratinocytes treated with soluble EGF displayed a highly proliferative, rather than migratory, phenotype. We then transitioned our photo-immobilization techniques to materials that may be more suitable as a wound dressing, such as silk fibroin films. Silk fibroin is a natural fiber with many desirable qualities for a biomaterial including high strength and elasticity, biocompatibility, a beta-keratin structure which closely mimics human keratin, and ease of fabrication and modification. These silk films can also provide topographical cues via simple cast molding of any feature on the micron scale. This system allowed simultaneous presentation of topographic cues, inhibitory and/or synergistic, with our chemotactic cues. Our preliminary data suggest keratinocytes remain viable on silk fibroin films, and that these films can be patterned with immobilized EGF to induce keratinocyte migration.

  12. Insulin-Like Growth Factor-I and Epidermal Growth Factor Regulate Insulin-Like Growth Factor Binding Protein3 (IGFBP-3) in the Human Keratinocyte Cell Line HaCaT

    Microsoft Academic Search

    Christopher J Wraight; George A Werther

    1995-01-01

    The human keratinocyte cell line HaCaT has a basal phenotype and secretes an insulin-like growth factor (IGF) binding protein, IGFBP-3, which modulates its IGF-I response. Keratinocytes are highly responsive to mitogenic stimulation by IGF-I and epidermal growth factor (EGF), but the effect of these growth factors on IGFBP secretion by keratinocytes is not known. We investigated the effects of IGF-I

  13. Altered expression of keratinocyte growth factor and its receptor in psoriasis.

    PubMed Central

    Finch, P. W.; Murphy, F.; Cardinale, I.; Krueger, J. G.

    1997-01-01

    One of the biological characteristics of psoriasis is excessive flaking of the skin. This is directly related to the marked hyperplasia of epidermal keratinocytes and to incomplete epidermal differentiation. Keratinocyte growth factor (KGF), a potent mitogen for human keratinocytes, is expressed by stromal cells. Alterations in the KGF signaling pathway might account for the epidermal hyperplasia associated with psoriasis. To test this hypothesis, we investigated the expression of KGF and its receptor (KGFR) in psoriasis tissue. KGF and KGFR mRNA levels were found to be frequently elevated in psoriatic skin specimens as compared with normal skin. Increased KGF transcript expression was localized to the dermal layer of the involved skin specimen using in situ hybridization. In contrast, KGFR transcript and protein expression was localized to the basal layer of keratinocytes in normal skin and to the basal and suprabasal layers of the psoriatic epidermis, coincident with the expanded proliferative keratinocyte pool. To identify molecules that might regulate KGFR expression we investigated the effects of various pharmacological agents and cytokines on KGFR synthesis by keratinocytes. Phorbol ester, interleukin-6, interferon-gamma, and ultraviolet B (UVB) treatment all led to substantial down-regulation of KGFR expression. The down-regulation of KGFR synthesis by UVB suggests a possible mechanism for the antiproliferative action of this agent in the treatment of psoriasis. Taken together, these results suggest that increased KGFR-mediated signaling in keratinocytes in the lesional epidermis might account in part for the epidermal hyperplasia in psoriasis. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 PMID:9403712

  14. Insulin-Like Growth Factors are Mitogenic for Human Keratinocytes and a Squamous Cell Carcinoma

    Microsoft Academic Search

    E. Kirk Neely; Vera B. Morhenn; Raymond L. Hintz; Darrell M. Wilson; Ron G. Rosenfeld

    1991-01-01

    Normal adult human keratinocytes in monolayer culture and SCL-1, a skin-derived squamous-cell carcinoma cell line, were investigated for the expression of receptors for insulin- like growth factors (IGF) and insulin. As demonstrated by affinity crosslinking, radiolabeled IGF-1, IGF-2, and insulin bound specifically to both cell types. Each cell expressed type I IGF receptors, with affinity for IGF-1 > IGF-2 >>

  15. Keratinocyte-Derived Vascular Permeability Factor (Vascular Endothelial Growth Factor) Is a Potent Mitogen for Dermal Microvascular Endothelial Cells

    Microsoft Academic Search

    Michael Detmar; Kiang-Teck Yeo; Janice A. Nagy; Livingston van de Water; Lawrence F. Brown; Brygida Berse; Brett M. Elicker; Stephen Ledbetter; Harold F. Dvorak

    1995-01-01

    Expression of vascular permeability factor\\/vascular endothelial growth factor (VPF\\/VEGF) is markedly increased in the epidermis of lesional psoriatic skin and in healing skin wounds. In this study, we characterized the effects of several cytokines and growth factors on the expression and secretion of VPF\\/VEGF mRNA and protein by cultured human epidermal keratinocytes, as well as the effect of VPF\\/VEGF on

  16. Fibroblast growth factor receptors 1 and 2 in keratinocytes control the epidermal barrier and cutaneous homeostasis

    PubMed Central

    Yang, Jingxuan; Meyer, Michael; Müller, Anna-Katharina; Böhm, Friederike; Grose, Richard; Dauwalder, Tina; Verrey, Francois; Kopf, Manfred; Partanen, Juha; Bloch, Wilhelm; Ornitz, David M.

    2010-01-01

    Fibroblast growth factors (FGFs) are master regulators of organogenesis and tissue homeostasis. In this study, we used different combinations of FGF receptor (FGFR)-deficient mice to unravel their functions in the skin. Loss of the IIIb splice variants of FGFR1 and FGFR2 in keratinocytes caused progressive loss of skin appendages, cutaneous inflammation, keratinocyte hyperproliferation, and acanthosis. We identified loss of FGF-induced expression of tight junction components with subsequent deficits in epidermal barrier function as the mechanism underlying the progressive inflammatory skin disease. The defective barrier causes activation of keratinocytes and epidermal ?? T cells, which produce interleukin-1 family member 8 and S100A8/A9 proteins. These cytokines initiate an inflammatory response and induce a double paracrine loop through production of keratinocyte mitogens by dermal cells. Our results identify essential roles for FGFs in the regulation of the epidermal barrier and in the prevention of cutaneous inflammation, and highlight the importance of stromal–epithelial interactions in skin homeostasis and disease. PMID:20308431

  17. Keratinocyte growth factor functions in epithelial induction during seminal vesicle development.

    PubMed Central

    Alarid, E T; Rubin, J S; Young, P; Chedid, M; Ron, D; Aaronson, S A; Cunha, G R

    1994-01-01

    Development of the seminal vesicle (SV) is elicited by androgens and is dependent on epithelial-mesenchymal interactions. Androgenic signal transmission from the androgen-receptor-positive mesenchyme to the epithelium has been postulated to involve paracrine factors. Keratinocyte growth factor (KGF), a member of the fibroblast growth factor family, is produced by stromal/mesenchymal cells and acts specifically on epithelial cells. The KGF transcript was detected by reverse transcription-polymerase chain reaction in newborn mouse SVs and by Northern blot analysis of RNA from cultured neonatal SV mesenchymal cells. Newborn SVs placed in organ culture undergo androgen-dependent growth and differentiation. Addition of a KGF-neutralizing monoclonal antibody to this system caused striking inhibition of both SV growth and branching morphogenesis. This inhibition was due to a decline in epithelial proliferation and differentiation, as the mesenchymal layer was not affected by anti-KGF treatment. When KGF (100 ng/ml) was substituted for testosterone in the culture medium, SV growth was approximately 50% that observed with an optimal dose of testosterone (10(-7) M). All of these findings suggest that KGF is present during a time of active SV morphogenesis and functions as an important mediator of androgen-dependent development. Images PMID:8302834

  18. Modulation of keratinocyte growth factor and its receptor in reepithelializing human skin

    PubMed Central

    1995-01-01

    We investigated the expression and distribution of keratinocyte growth factor (KGF) (FGF-7) and its receptor (KGFR) during reepithelialization of human skin. KGF mRNA levels increased rapidly by 8-10-fold and remained elevated for several days. In contrast, KGFR transcript levels decreased early but were significantly elevated by 8-9 d. A KGF- immunoglobulin G fusion protein (KGF-HFc), which specifically and sensitively detects the KGFR, localized the receptor to differentiating keratinocytes of control epidermis, but revealed a striking decrease in receptor protein expression during the intermediate period of reepithelization. Suramin, which blocked KGF binding and stripped already bound KGF from its receptor, failed to unmask KGFRs in tissue sections from the intermediate phase of wound repair. The absence of KGFR protein despite increased KGFR transcript levels implies functional receptor downregulation in the presence of increased KGF. This temporal modulation of KGF and KGFRs provides strong evidence for the functional involvement of KGF in human skin reepithelialization. PMID:7595207

  19. Ultraviolet irradiation induces keratinocyte proliferation and epidermal hyperplasia through the activation of the epidermal growth factor receptor

    Microsoft Academic Search

    Taghrid B. El-Abaseri; Sumanth Putta; Laura A. Hansen

    2006-01-01

    Chronic exposure to ultraviolet (UV) irradiation induces skin cancer, in part, through epigenetic mechanisms that result in the deregulation of cell proliferation. UV irradi- ation also rapidly activates the epidermal growth factor receptor (EGFR). Since EGFR activation is strongly mito- genic in many cell types including keratinocytes of the skin, we hypothesized that UV-induced cutaneous proliferation results from EGFR activation.

  20. Expression of keratinocyte growth factor and its receptor in human breast cancer.

    PubMed Central

    Bansal, G. S.; Cox, H. C.; Marsh, S.; Gomm, J. J.; Yiangou, C.; Luqmani, Y.; Coombes, R. C.; Johnston, C. L.

    1997-01-01

    The level of expression of keratinocyte growth factor (KGF) mRNA has been measured in human breast cell lines, purified populations of epithelial cells, myoepithelial cells and fibroblasts from reduction mammoplasty tissue and a panel of 42 breast cancers and 30 non-malignant human breast tissues using a semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) procedure. We found similar levels of KGF mRNA in malignant and non-malignant breast tissues. The study of the amount of KGF mRNA in breast cell lines and purified populations of cells revealed that fibroblasts are the predominant source of KGF with malignant and non-malignant epithelial cells containing very low levels of KGF mRNA. We have examined the distribution of fibroblast growth factor receptor (FGFR)-2-IIIb, which is a high-affinity receptor for KGF and find that it is present on malignant and non-malignant epithelial cells. The level of FGFR-2-IIIb present on breast cancer cell lines was sufficient for KGF stimulation of breast cancer cell proliferation. Other members of the fibroblast growth factor family have been either not expressed in the human breast (FGF3, FGF4) or have been found at much reduced levels in breast cancer (FGF1, FGF2) and this is the first member of the family to potentially influence the progression of breast cancer through stimulation of cell division. Images Figure 1 Figure 3 Figure 4 PMID:9184170

  1. A Keratinocyte Cell Line Synthesizes a Predominant Insulin-Like Growth Factor-Binding Protein (IGFBP-3) that Modulates Insulin-Like Growth Factor-I Action

    Microsoft Academic Search

    Christopher J. Wraight; Mari M. Murashita; Vincenzo C. Russo; George A. Werther

    1994-01-01

    Insulin-like growth factor-I (IGF-I) is an important regulator of epidermal proliferation and has been shown in vitro to be a powerful stimulator of keratinocyte growth. It is synthesized by fibroblasts in the dermis, along with several IGF-binding proteins (IGFBPs), which are known to modulate IGF-I responsiveness of virtually all tissues studied. Because it was not known how or in what

  2. Keratinocyte growth factor protects epidermis and hair follicles from cell death induced by UV irradiation, chemotherapeutic or cytotoxic agents.

    PubMed

    Braun, Susanne; Krampert, Monika; Bodó, Enikö; Kümin, Angelika; Born-Berclaz, Christiane; Paus, Ralf; Werner, Sabine

    2006-12-01

    Owing to its potent cytoprotective properties for epithelial cells, keratinocyte growth factor (KGF) is successfully used for the treatment of chemotherapy- and radiotherapy-induced oral mucositis in cancer patients. It is therefore of major interest to determine possible clinical applications of KGF in other organs and in different stress situations and to unravel common and organ-specific mechanisms of KGF action. Here we show that KGF protects human keratinocytes from the toxicity of xenobiotics with electrophilic and oxidative properties and reduces the cell death induced by UV irradiation. In contrast to other cell types, cytoprotection of keratinocytes by KGF is not a direct anti-apoptotic effect but requires de novo protein synthesis. The in vitro findings are clinically relevant because KGF protected keratinocytes in organ-cultured human scalp hair follicles from the toxicity of the xenobiotic menadione. Moreover, injection of KGF into murine back skin markedly reduced cell death in the epidermis after UVB irradiation. This activity is dependent on FGF receptor signaling because it was abrogated in transgenic mice expressing a dominant-negative FGF receptor mutant in keratinocytes. Taken together, our results encourage the use of KGF for skin protection from chemical and physical insults. PMID:17090603

  3. Regulation of the expression of stromelysin-2 by growth factors in keratinocytes: implications for normal and impaired wound healing.

    PubMed Central

    Madlener, M; Mauch, C; Conca, W; Brauchle, M; Parks, W C; Werner, S

    1996-01-01

    Keratinocyte growth factor (KGF) has been implicated in wound re-epithelialization and branching morphogenesis of several organs. To determine whether KGF induces these effects via induction of matrix metalloproteinase expression we have analysed the effect of KGF on the expression of stromelysin-2 in cultured HaCaT keratinocytes. Here we show a strong induction of stromelysin-2 mRNA within 5-8 h of stimulation of these cells with KGF. The degree of induction was similar to that achieved by treatment with epidermal growth factor or tumour necrosis factor alpha, whereas the stimulatory effect of transforming growth factor beta 1 was even stronger. To determine whether the induction of stromelysin-2 expression by growth factors and cytokines might be important for wound healing, we analysed the expression of this gene during the healing process of full-thickness excisional wounds in mice. Whereas stromelysin-2 mRNA could hardly be detected in unwounded skin, a biphasic induction was seen after injury and highest levels were found at days 1 and 5 after wounding. Hybridization in situ revealed the presence of stromelysin-2 mRNA in basal keratinocytes at the wound edge but not in the underlying mesenchymal tissue. During impaired wound healing as seen in glucocorticoid-treated mice, stromelysin-2 expression was significantly increased compared with untreated control mice. Taken together, these results suggest that correct regulation of this broad-spectrum metalloproteinase might be important for normal repair. PMID:8973581

  4. Effect of transforming growth factor-?1 on parathyroid hormone-related protein secretion and mRNA expression by normal human keratinocytes in vitro

    Microsoft Academic Search

    James R. Werkmeister; Eric A. G. Blomme; Michelle T. Weckmann; Andrea Gröne; Laurie K. McCauley; Andrew B. Wade; John O’Rourke; Charles C. Capen; Thomas J. Rosol

    1998-01-01

    Parathyroid hormone-related protein (PTHrP) is produced by a wide range of neoplastic and normal cells, including keratinocytes\\u000a where it may regulate growth and differentiation. Transforming growth factor-? (TGF-?) is a growth factor produced by many\\u000a cells, including keratinocytes where it regulates epidermal homeostasis. TGF-? has been reported to be cosecreted with PTHrP\\u000a in some neoplasms and to stimulate PTHrP production

  5. The protective effect of recombinant human keratinocyte growth factor on radiation-induced pulmonary toxicity in rats

    Microsoft Academic Search

    Liguang Chen; David M. Brizel; Zahid N. Rabbani; Thaddeus V. Samulski; Catherine L. Farrell; Nicole Larrier; Mitchell S. Anscher; Zeljko. Vujaskovic

    2004-01-01

    Purpose: Radiation-induced lung toxicity is a significant dose-limiting side effect of radiotherapy for thoracic tumors. Recombinant human keratinocyte growth factor (rHuKGF) has been shown to be a mitogen for type II pneumocytes. The purpose of this study was to determine whether rHuKGF prevents or ameliorates the severity of late lung damage from fractionated irradiation in a rat model. Methods and

  6. Secretion of keratinocyte growth factor by cultured human endometrial stromal cells is induced through a cyclic adenosine monophosphate-dependent pathway

    Microsoft Academic Search

    Kaei Nasu; Kazuyo Arima; Kayo Fujisawa; Masakazu Nishida; Kengo Kai; Isao Miyakawa

    2002-01-01

    Objective: To evaluate the effects of known modulators of endometrial function on the production of keratinocyte growth factor by endometrial stromal cells.Design: The effects of dibutyryl-cyclic adenosine monophosphate (db-cAMP), 12-O-tetradecanoylphorbol 13-acetate (TPA), ethinyl estradiol-17? (EE), and medroxyprogesterone acetate (MPA) on the secretion of keratinocyte growth factor by endometrial stromal cells were investigated.Setting: Research laboratory at a university medical school.Patient(s): Eleven

  7. Strengthening the Skin with Topical Delivery of Keratinocyte Growth Factor-1 Using a Novel DNA Plasmid

    PubMed Central

    Dou, Chunqing; Lay, Frank; Ansari, Amir Mehdi; Rees, Donald J; Ahmed, Ali Karim; Kovbasnjuk, Olga; Matsangos, Aerielle E.; Du, Junkai; Hosseini, Sayed Mohammad; Steenbergen, Charles; Fox-Talbot, Karen; Tabor, Aaron T.; Williams, James A; Liu, Lixin; Marti, Guy P; Harmon, John W

    2014-01-01

    Fragile skin, susceptible to decubitus ulcers and incidental trauma, is a problem particularly for the elderly and for those with spinal cord injury. Here, we present a simple approach to strengthen the skin by the topical delivery of keratinocyte growth factor-1 (KGF-1) DNA. In initial feasibility studies with the novel minimalized, antibiotic-free DNA expression vector, NTC8385-VA1, the reporter genes luciferase and enhanced green fluorescent protein were delivered. Transfection was documented when luciferase expression significantly increased after transfection. Microscopic imaging of enhanced green fluorescent protein–transfected skin showed green fluorescence in hair follicles, hair shafts, and dermal and superficial epithelial cells. With KGF-1 transfection, KGF-1 mRNA level and protein production were documented with quantitative reverse transcriptase–polymerase chain reaction and immunohistochemistry, respectively. Epithelial thickness of the transfected skin in the KGF group was significantly increased compared with the control vector group (26?±?2 versus 16?±?4 µm) at 48 hours (P = 0.045). Dermal thickness tended to be increased in the KGF group (255?±?36 versus 162?±?16 µm) at 120 hours (P = 0.057). Biomechanical assessment showed that the KGF-1–treated skin was significantly stronger than control vector–transfected skin. These findings indicate that topically delivered KGF-1 DNA plasmid can increase epithelial thickness and strength, demonstrating the potential of this approach to restore compromised skin. PMID:24434934

  8. Keratinocyte growth factor-2 is protective in lipopolysaccharide-induced acute lung injury in rats.

    PubMed

    Tong, Lin; Bi, Jing; Zhu, Xiaodan; Wang, Guifang; Liu, Jie; Rong, Linyi; Wang, Qin; Xu, Nuo; Zhong, Ming; Zhu, Duming; Song, Yuanlin; Bai, Chunxue

    2014-09-15

    Keratinocyte growth factor-2 (KGF-2) plays a key role in lung development, but its role in acute lung injury has not been well characterized. Lipopolysaccharide instillation caused acute lung injury, which significantly elevated lung wet-to-dry weight ratio, protein and neutrophils in bronchoalveolar lavage fluid (BALF), inhibited surfactant protein A and C expression in lung tissue, and increased pathological injury. Pretreatment with KGF-2 improved the above lung injury parameters, partially restored surfactant protein A and C expression, and KGF-2 given 2-3 days before LPS challenge showed maximum lung injury improvement. Pretreatment with KGF-2 also markedly reduced the levels of TNF-?, MIP-2, IL-1? and IL-6 in BALF and the levels of IL-1? and IL-6 in lung tissue. Histological analysis showed there was increased proliferation of alveolar type II epithelial cells in lung parenchyma, which reached maximal 2 days after KGF-2 instillation. Intratracheal administration of KGF-2 attenuates lung injury induced by LPS, suggesting KGF-2 may be potent in the intervention of acute lung injury. PMID:24973472

  9. Keratinocytes express cytokines and nerve growth factor in response to neuropeptide activation of the ERK1/2 and JNK MAPK transcription pathways.

    PubMed

    Shi, Xiaoyou; Wang, Liping; Clark, J David; Kingery, Wade S

    2013-09-10

    Sensory neurons innervating the skin can release neuropeptides that are believed to modulate cellular proliferation, wound healing, pigmentation, and keratinocyte innate immune responses. While the ability of neuropeptides to stimulate keratinocyte production of inflammatory mediators has been demonstrated, there is no information concerning the mechanisms by which neuropeptide activation of keratinocyte cell surface receptors ultimately leads to the up-regulation of mediator production. In this study we used a keratinocyte cell line to identify the presence of substance P (SP) and calcitonin gene-related peptide (CGRP) receptors on keratinocytes and examined the effects of SP and CGRP stimulation on keratinocyte neuropeptide signaling, cell proliferation, and interleukin-1? (IL-1?), interleukin-6 (IL-6), tumor necrosis factor ? (TNF-?), and nerve growth factor (NGF) expression. Neuropeptide stimulation caused an up-regulation of neuropeptide receptor expression in keratinocytes and a dramatic increase in keratinocyte secretion of SP and CGRP, suggesting possible autocrine or paracrine stimulatory effects and amplification of neuropeptide signaling. Both SP and CGRP concentration-dependently stimulated cellular proliferation and the expression and secretion of inflammatory cytokines and NGF in keratinocytes. SP also activated all 3 families of mitogen activated protein kinase (MAPK) and nuclear factor ?B (NF?B) in keratinocytes, while CGRP only activated p38 and extracellular signal related kinase1/2 (ERK1/2) MAPKs. Neuropeptide stimulated inflammatory mediatory production in keratinocytes was reversed by ERK1/2 and JNK inhibitors. The current study is the first to observe; 1) that CGRP stimulates keratinocyte expression of CGRP and its receptor complex, 2) that SP and CGRP stimulate IL-6 and TNF-? secretion in keratinocytes, 3) that SP activated all three MAPK families and the NF?B transcriptional signaling pathway in keratinocytes, and 4) that SP and CGRP stimulated inflammatory mediator production in keratinocytes is dependent on ERK1/2 and JNK activation. These studies provide evidence suggesting that disruption of ERK1/2 and JNK signaling may potentially be an effective therapy for inflammatory skin diseases and pain syndromes mediated by exaggerated sensory neuron-keratinocyte signaling. PMID:23958840

  10. Regulation of parathyroid hormone-related protein gene expression by epidermal growth factor-family ligands in primary human keratinocytes

    Microsoft Academic Search

    Yong-Mee Cho; Davina A Lewis; Peter F Koltz; Virgile Richard; Todd A Gocken; Thomas J Rosol; Raymond L Konger; Dan F Spandau; John Foley

    2004-01-01

    Cultured primary human keratinocytes were the first non-cancer-derived cell type reported to produce the humoral hypercalcemia factor, parathyroid hormone- related protein (PTHrP). Emerging evidence suggests that only a subset of keratinocytes produce high levels of PTHrP in vivo. We found that the PTHrP mRNA content of intact human skin was minimal, whereas transcripts were easily detectable in primary keratinocytes derived

  11. Inhibition of growth of normal and human papillomavirus-transformed keratinocytes in monolayer and organotypic cultures by interferon-gamma and tumor necrosis factor-alpha.

    PubMed Central

    Delvenne, P.; al-Saleh, W.; Gilles, C.; Thiry, A.; Boniver, J.

    1995-01-01

    The growth response of normal and human papillomavirus (HPV)-transformed cervical keratinocytes to interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha was investigated in monolayer and organotypic raft cultures. The proliferation rates of monolayer cultures were assessed by [3H]TdR incorporation and fluorimetric DNA titration. The growth of keratinocytes in organotypic cultures was estimated by their ability to stratify on collagen rafts and by immunohistochemistry for Ki67 antigen expression. IFN-gamma reduced the DNA synthesis of normal and HPV-transformed keratinocytes in monolayer cultures and exerted a marked growth inhibitory effect in organotypic raft cultures. In control raft cultures, normal keratinocytes produced an epithelial sheet of approximately 10 cells in thickness that closely resembled normal cervical epithelium and was characterized by sparse Ki67 antigen-positive cells whereas HPV-transformed keratinocytes produced up to 15 poorly differentiated epithelial layers that were reminiscent of high grade cervical lesions seen in vivo and exhibited a full thickness Ki67 antigen expression. When normal and HPV-transformed keratinocytes were maintained in the presence of IFN-gamma, the epithelial sheet was reduced to a few cells in thickness and the density of Ki67 antigen-positive cells was decreased. A more pronounced growth inhibitory effect in monolayer and organotypic cultures was observed when IFN-gamma was associated with tumor necrosis factor-alpha Tumor necrosis factor-alpha alone reduced the DNA synthesis of normal keratinocytes but was significantly less effective than IFN-gamma to inhibit the growth of HPV-transformed keratinocytes. These results suggest that similar responses in vivo to regulatory molecules may play a role in the development of HPV-related lesions. Images Figure 1 PMID:7887441

  12. Epidermal Growth Factor Receptor-dependent Control of Keratinocyte Survival and Bcl-xL Expression through a MEK-dependent Pathway

    Microsoft Academic Search

    Monika Jost; Teresa M. Huggett; Csaba Kari; Lawrence H. Boise; Ulrich Rodeck

    2001-01-01

    Previous work has shown that the epidermal growth factor receptor (EGFR) tyrosine kinase moiety provides protection to normal human keratinocytes against ap- optosis. This protection is, at least in part, due to EGFR- dependent expression of the antiapoptotic Bcl-2 family member, Bcl-xL. Here we focused on intracellular signal- ing pathways relevant to keratinocyte survival and\\/or Bcl-xL expression. By using pharmacological

  13. Effects of Keratinocyte Growth Factor on the Proliferation and Radiation Survival of Human Squamous Cell Carcinoma Cell Lines In Vitro and In Vivo

    Microsoft Academic Search

    Shoucheng Ning; Chaoxiang Shui; Waqqar B Khan; William Benson; David L Lacey; Susan J Knox

    1998-01-01

    Purpose: Keratinocyte growth factor (KGF) has potent mitogenic activity on normal epithelial cells and has been found to enhance intestinal crypt cell survival in irradiated mice and to prevent radiation and chemotherapy-induced mucositis in animal models. The purpose of the study reported here is to investigate the effect of recombinant human KGF on the proliferation and survival of human squamous

  14. Differential expression of heparin-binding EGF-like growth factor (HB-EGF) mRNA in normal human keratinocytes induced by a variety of natural and synthetic retinoids

    Microsoft Academic Search

    Kotaro Yoshimura; Gentaro Uchida; Mutsumi Okazaki; Yukie Kitano; Kiyonori Harii

    2003-01-01

    It was recently revealed that epidermal growth following topical treatment with all-trans retinoic acid (atRA) was at least partly induced by heparin-binding epidermal growth factor-like growth factor (HB-EGF) released from suprabasal keratinocytes. Since proliferation of keratinocytes appears to be one of the critical roles of atRA in depigmentation treatment and promotion of wound healing, HB-EGF is considered suitable for assessing

  15. Bronchoalveolar sublineage specification of pluripotent stem cells: effect of dexamethasone plus cAMP-elevating agents and keratinocyte growth factor.

    PubMed

    Katsirntaki, Katherina; Mauritz, Christina; Olmer, Ruth; Schmeckebier, Sabrina; Sgodda, Malte; Puppe, Verena; Eggenschwiler, Reto; Duerr, Julia; Schubert, Susanne C; Schmiedl, Andreas; Ochs, Matthias; Cantz, Tobias; Salwig, Isabelle; Szibor, Marten; Braun, Thomas; Rathert, Christian; Martens, Andreas; Mall, Marcus A; Martin, Ulrich

    2015-02-01

    Respiratory progenitors can be efficiently generated from pluripotent stem cells (PSCs). However, further targeted differentiation into bronchoalveolar sublineages is still in its infancy, and distinct specifying effects of key differentiation factors are not well explored. Focusing on airway epithelial Clara cell generation, we analyzed the effect of the glucocorticoid dexamethasone plus cAMP-elevating agents (DCI) on the differentiation of murine embryonic and induced pluripotent stem cells (iPSCs) into bronchoalveolar epithelial lineages, and whether keratinocyte growth factor (KGF) might further influence lineage decisions. We demonstrate that DCI strongly induce expression of the Clara cell marker Clara cell secretory protein (CCSP). While KGF synergistically supports the inducing effect of DCI on alveolar markers with increased expression of surfactant protein (SP)-C and SP-B, an inhibitory effect on CCSP expression was shown. In contrast, neither KGF nor DCI seem to have an inducing effect on ciliated cell markers. Furthermore, the use of iPSCs from transgenic mice with CCSP promoter-dependent lacZ expression or a knockin of a YFP reporter cassette in the CCSP locus enabled detection of derivatives with Clara cell typical features. Collectively, DCI was shown to support bronchoalveolar specification of mouse PSCs, in particular Clara-like cells, and KGF to inhibit bronchial epithelial differentiation. The targeted in vitro generation of Clara cells with their important function in airway protection and regeneration will enable the evaluation of innovative cellular therapies in animal models of lung diseases. PMID:25316003

  16. A protective role for keratinocyte growth factor in a murine model of chemotherapy and radiotherapy-induced mucositis

    SciTech Connect

    Borges, Luis [Departments of Hematology, Cancer Biology, and Pathology, Amgen Inc., Thousand Oaks, CA (United States)]. E-mail: borgesl@amgen.com; Rex, Karen L. [Departments of Hematology, Cancer Biology, and Pathology, Amgen Inc., Thousand Oaks, CA (United States); Chen, Jennifer N. [Departments of Hematology, Cancer Biology, and Pathology, Amgen Inc., Thousand Oaks, CA (United States); Wei, Ping [Departments of Hematology, Cancer Biology, and Pathology, Amgen Inc., Thousand Oaks, CA (United States); Kaufman, Stephen [Departments of Hematology, Cancer Biology, and Pathology, Amgen Inc., Thousand Oaks, CA (United States); Scully, Sheila [Departments of Hematology, Cancer Biology, and Pathology, Amgen Inc., Thousand Oaks, CA (United States); Pretorius, James K. [Departments of Hematology, Cancer Biology, and Pathology, Amgen Inc., Thousand Oaks, CA (United States); Farrell, Catherine L. [Departments of Hematology, Cancer Biology, and Pathology, Amgen Inc., Thousand Oaks, CA (United States)

    2006-09-01

    Purpose: To evaluate the activity of palifermin (rHuKGF) in a murine model of mucosal damage induced by a radiotherapy/chemotherapy (RT/CT) regimen mimicking treatment protocols used in head-and-neck cancer patients. Methods and Materials: A model of mucosal damage induced by RT/CT was established by injecting female BDF1 mice with cisplatin (10 mg/kg) on Day 1; 5-fluorouracil (40 mg/kg/day) on Days 1-4, and irradiation (5 Gy/day) to the head and neck on Days 1-5. Palifermin was administered subcutaneously on Days -2 to 0 (5 mg/kg/day) and on Day 5 (5 mg/kg). Evaluations included body weight, organ weight, keratinocyte growth factor receptor expression, epithelial thickness, and cellular proliferation. Results: Initiation of the radiochemotherapeutic regimen resulted in a reduction in body weight in control animals. Palifermin administration suppressed weight loss and resulted in increased organ weight (salivary glands and small intestine), epithelial thickness (esophagus and tongue), and cellular proliferation (tongue and salivary glands). Conclusions: Administration of palifermin before RT/CT promotes cell proliferation and increases in epithelial thickness in the oral mucosa, salivary glands, and digestive tract. Palifermin administration before and after RT/CT mitigates weight loss and a trophic effect on the intestinal mucosa and salivary glands, suggesting that palifermin use should be investigated further in the RT/CT settings, in which intestinal mucositis and salivary gland dysfunction are predominant side effects of cytotoxic therapy.

  17. Long-Term Maintenance of Limbal Epithelial Progenitor Cells Using Rho Kinase Inhibitor and Keratinocyte Growth Factor

    PubMed Central

    Miyashita, Hideyuki; Yokoo, Seiichi; Yoshida, Satoru; Kawakita, Tetsuya; Yamagami, Satoru; Tsubota, Kazuo

    2013-01-01

    Corneal epithelial stem cells are located in the limbus, the junction between the cornea and the conjunctiva. A limbal epithelium model in vitro would be useful for the study of epithelial stem cells, as well as improving the quality of cultivated epithelial sheets for the treatment of limbal stem cell deficiency. In this study, we succeeded in constructing a limbal epithelium-like structure that could be maintained for at least 5 months in vitro. We modified conventional medium by replacing epidermal growth factor with keratinocyte growth factor (KGF) and adding Y-27632, a rho kinase inhibitor. Using this medium, epithelial cells freshly isolated from human limbus were cocultured with human mesenchymal stem cell-derived feeder cells. Cells formed a stratified layer without air exposure, and both basal and suprabasal layers maintained their unique morphologies for up to 5 months. Basal layers expressed the progenitor marker p63 uniformly and K15 heterogeneously. Expressions of PAX6, K3, and K12 indicated that cell sheets underwent normal differentiation in the corneal epithelium lineage. Although medium was changed daily after day 7, cell debris was observed every day, suggesting that cell sheets underwent turnover. Furthermore, secondary colonies were observed from cells dissociated from 1-month and 3-month cultured sheets. In conclusion, human limbal epithelial cell sheet cultures with KGF and Y-27632 maintained stratification, high expression of both stem/progenitor markers and differentiation markers, and colony-forming cells long-term. This protocol may be useful as an in vitro limbal epithelial model for basic studies. PMID:23981725

  18. Estradiol Protects Dermal Hyaluronan/Versican Matrix during Photoaging by Release of Epidermal Growth Factor from Keratinocytes*

    PubMed Central

    Röck, Katharina; Meusch, Michael; Fuchs, Nikola; Tigges, Julia; Zipper, Petra; Fritsche, Ellen; Krutmann, Jean; Homey, Bernhard; Reifenberger, Julia; Fischer, Jens W.

    2012-01-01

    Hyaluronan (HA) and versican are key components of the dermis and are responsive to ultraviolet (UV)B-induced remodeling. The aim of this study was to explore the molecular mechanisms mediating the effects of estrogen (E2) on HA-rich extracellular matrix during photoaging. Hairless skh-1 mice were irradiated with UVB (three times, 1 minimal erythema dose (80 mJ/cm2), weekly) for 10 weeks, and endogenous sex hormone production was abrogated by ovariectomy. Subcutaneous substitution of E2 by means of controlled-release pellets caused a strong increase in the dermal HA content in both irradiated and nonirradiated skin. The increase in dermal HA correlated with induction of HA synthase HAS3 by E2. Expression of splice variant 2 of the HA-binding proteoglycan versican was also increased by E2. In search of candidate mediators of these effects, it was found that E2 strongly induced the expression of epidermal growth factor (EGF) in UVB-irradiated epidermis in vivo and in keratinocytes in vitro. EGF in turn up-regulated the expression of HAS3 and versican V2 in dermal fibroblasts. HAS3 knockdown by shRNA caused inhibition of fibroblast proliferation. Furthermore, HAS3 and versican V2 induction by E2 correlated positively with proliferation in vivo. In addition, the accumulation of inflammatory macrophages, expression of inducible cyclooxygenase 2, as well as proinflammatory monocyte chemotactic protein 1 were decreased in response to E2 in the dermis. Collectively, these data suggest that E2 treatment increases the amount of dermal HA and versican V2 via paracrine release of EGF, which may be implicated in the pro-proliferative and anti-inflammatory effects of E2 during photoaging. PMID:22493503

  19. Pharmacokinetics of topically applied recombinant human keratinocyte growth factor-2 in alkali-burned and intact rabbit eye.

    PubMed

    Cai, Jianqiu; Dou, Guifang; Zheng, Long; Yang, Ting; Jia, Xuechao; Tang, Lu; Huang, Yadong; Wu, Wencan; Li, Xiaokun; Wang, Xiaojie

    2015-07-01

    Keratinocyte growth factor-2 (KGF-2), an effective agent in the development of epithelial tissue and regeneration during corneal wound healing, is a potential therapeutic option to treat the corneal diseases with corneal epithelial defects. However the tissue distribution and pharmacokinetics of KGF-2 have not been explored yet in eye upon topical application. Using (125)I-labeled recombinant human KGF-2 ((125)I-rhKGF-2), tissue distribution of rhKGF-2 in alkali-burned and control rabbit eyes was studied. Our results revealed that (125)I-rhKGF-2 was distributed to all eye tissues examined. The highest radioactivity level was found in the cornea, followed by iris, sclera, ciliary body, lens, aqueous humor, vitreous body, and serum in a greatest to least order. The levels of (125)I-rhKGF-2 were higher in corneas of alkali-burned eyes than those in control eyes though without statistical significance. Calculated pharmacokinetic parameters of t1/2, Cmax, and Tmax of rhKGF-2 in the rabbit corneas were 3.4 h, 135.2 ng/ml, and 0.5 h, respectively. In iris, lens, aqueous humor, and tear, t1/2, Cmax, and Tmax values were 6.2, 6.5, 5.2, and 2.5 h; 23.2, 4.5, 24.1, and 29,498.9 ng/ml; and 1.0, 0.5, 0.5, and 1.0 h, respectively. Predominant and rapid accumulation of rhKGF-2 in corneas suggests that therapeutic doses of rhKGF-2 could be delivered by topical application for treatment of corneal diseases. PMID:25987499

  20. Highly efficient expression of functional recombinant human keratinocyte growth factor 1 and its protective effects on hepatocytes.

    PubMed

    Xue, Ping; Zhu, Xiaojing; Shi, Junqing; Fu, Hongqi; Zhang, Jian; Liu, Min; Jiang, Chao; Li, Xiaokun

    2014-05-01

    Three forms of recombinant human keratinocyte growth factor 1 (rhKGF1) with or without the native signal peptide or a 23-amino acid truncation were expressed in Spodoptera frugiperda 9 (Sf9) cells by designing with insect codon usage. Immunoblotting demonstrated that these rhKGF1 proteins were recognized by a human anti-KGF1 antibody. The multiplicity of infection and timing of harvest had a significant effect on protein yield, protein quality, and cytotoxicity. Our results indicated that the native signal peptide directed KGF1 secretion from insect cells, reaching a maximum at 60 h postinfection. Although secretion of rhKGF1194 was less efficient than that of rhKGF1163 and rhKGF1140, protein secretion is an attractive pathway for simple purification of biologically active rhKGF1 at a high yield. Moreover, the sizes of rhKGF1194 and rhKGF1163 were similar (20 kDa), suggesting that the signal peptide may be recognized and removed in Sf9 cells. A 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay was used to analyze the biological function of rhKGF1, indicating that the three forms of rhKGF1 had a similar mitogenic function in BaF3 cells. Furthermore, to elucidate the effect of rhKGF1 on cytoprotection of liver cells, we used KGF1 pretreatment of an acute liver injury model. The results indicated that rhKGF1 prevented necrosis and apoptosis of CCl4-treated HL7702 cells in vitro and in vivo. These results suggest that KGF1 may be a candidate therapeutic drug for acute liver injury. PMID:24463717

  1. Estradiol protects dermal hyaluronan/versican matrix during photoaging by release of epidermal growth factor from keratinocytes.

    PubMed

    Röck, Katharina; Meusch, Michael; Fuchs, Nikola; Tigges, Julia; Zipper, Petra; Fritsche, Ellen; Krutmann, Jean; Homey, Bernhard; Reifenberger, Julia; Fischer, Jens W

    2012-06-01

    Hyaluronan (HA) and versican are key components of the dermis and are responsive to ultraviolet (UV)B-induced remodeling. The aim of this study was to explore the molecular mechanisms mediating the effects of estrogen (E(2)) on HA-rich extracellular matrix during photoaging. Hairless skh-1 mice were irradiated with UVB (three times, 1 minimal erythema dose (80 mJ/cm(2)), weekly) for 10 weeks, and endogenous sex hormone production was abrogated by ovariectomy. Subcutaneous substitution of E(2) by means of controlled-release pellets caused a strong increase in the dermal HA content in both irradiated and nonirradiated skin. The increase in dermal HA correlated with induction of HA synthase HAS3 by E(2). Expression of splice variant 2 of the HA-binding proteoglycan versican was also increased by E(2). In search of candidate mediators of these effects, it was found that E(2) strongly induced the expression of epidermal growth factor (EGF) in UVB-irradiated epidermis in vivo and in keratinocytes in vitro. EGF in turn up-regulated the expression of HAS3 and versican V2 in dermal fibroblasts. HAS3 knockdown by shRNA caused inhibition of fibroblast proliferation. Furthermore, HAS3 and versican V2 induction by E(2) correlated positively with proliferation in vivo. In addition, the accumulation of inflammatory macrophages, expression of inducible cyclooxygenase 2, as well as proinflammatory monocyte chemotactic protein 1 were decreased in response to E(2) in the dermis. Collectively, these data suggest that E(2) treatment increases the amount of dermal HA and versican V2 via paracrine release of EGF, which may be implicated in the pro-proliferative and anti-inflammatory effects of E(2) during photoaging. PMID:22493503

  2. trans-3,4'-Dimethyl-3-hydroxyflavanone, a hair growth enhancing active component, decreases active transforming growth factor beta2 (TGF-beta2) through control of urokinase-type plasminogen activator (uPA) on the surface of keratinocytes.

    PubMed

    Sasajima, Michiyo; Moriwaki, Shigeru; Hotta, Mitsuyuki; Kitahara, Takashi; Takema, Yoshinori

    2008-03-01

    trans-3,4'-Dimethyl-3-hydroxyflavanone (t-flavanone) is a synthetic compound with hair growth enhancing activity that is effective against male pattern alopecia. t-Flavanone was designed as a derivative of astilbin, the active hair growth enhancing component of Hypericum perforatum extracts. This study was designed to elucidate the mechanism of hair growth enhancement by t-flavanone. We investigated the effects of t-flavanone on transforming growth factor beta (TGF-beta), a known catagen-inducing factor induced in hair papilla cells by male hormone. When t-flavanone was added to cocultures of human hair papilla cells and human keratinocytes, there was no change in the total level of TGF-beta2. However, levels of active TGF-beta2 were reduced, suggesting the involvement of t-flavanone in the activation pathway of TGF-beta2. In order to investigate the effects of t-flavanone on TGF-beta2 activation by human keratinocytes, we evaluated the level of active TGF-beta2 converted from the inactive form in t-flavanone-treated human keratinocytes. The amount of active TGF-beta2 was reduced compared with controls suggesting that t-flavanone suppresses the TGF-beta2 activation cascade in human keratinocytes. We then examined the activity of urokinase-type plasminogen activator (uPA), the rate-limiting enzyme in the TGF-beta2 activation cascade, in t-flavanone-treated human keratinocytes. We found that t-flavanone reduces uPA activity on the keratinocyte surface. t-Flavanone is a hair growth enhancing component that has a novel mechanism of action which suppresses TGF-beta2 activation, and thereby is expected to have therapeutic effects on other types of alopecia in addition to male pattern alopecia. PMID:18310908

  3. Keratinocyte-specific POU transcription factor hSkn-1a represses the growth of cervical cancer cell lines

    Microsoft Academic Search

    Yutaka Enomoto; Kikuko Enomoto; Tadaichi Kitamura; Tadahito Kanda

    2004-01-01

    The POU transcription factor human Skn-1a (hSkn-1a) specifically promotes the proliferation of keratinocytes and enhances their differentiation. We examined the effects of hSkn-1a on cervical cancer cell lines of epithelial origin, in which the differentiation program is interrupted. From HeLa\\/Tet-On, a clone that can be induced to make hSkn-1a by doxycycline (HeLa\\/hSkn-1a) was prepared and characterized. Shortly after the induction,

  4. Activated Protein C Enhances Human Keratinocyte Barrier Integrity via Sequential Activation of Epidermal Growth Factor Receptor and Tie2*

    PubMed Central

    Xue, Meilang; Chow, Shu-Oi; Dervish, Suat; Chan, Yee-Ka Agnes; Julovi, Sohel M.; Jackson, Christopher J.

    2011-01-01

    Keratinocytes play a critical role in maintaining epidermal barrier function. Activated protein C (APC), a natural anticoagulant with anti-inflammatory and endothelial barrier protective properties, significantly increased the barrier impedance of keratinocyte monolayers, measured by electric cell substrate impedance sensing and FITC-dextran flux. In response to APC, Tie2, a tyrosine kinase receptor, was rapidly activated within 30 min, and relocated to cell-cell contacts. APC also increased junction proteins zona occludens, claudin-1 and VE-cadherin. Inhibition of Tie2 by its peptide inhibitor or small interfering RNA abolished the barrier protective effect of APC. Interestingly, APC did not activate Tie2 through its major ligand, angiopoietin-1, but instead acted by binding to endothelial protein C receptor, cleaving protease-activated receptor-1 and transactivating EGF receptor. Furthermore, when activation of Akt, but not ERK, was inhibited, the barrier protective effect of APC on keratinocytes was abolished. Thus, APC activates Tie2, via a mechanism requiring, in sequential order, the receptors, endothelial protein C receptor, protease-activated receptor-1, and EGF receptor, which selectively enhances the PI3K/Akt signaling to enhance junctional complexes and reduce keratinocyte permeability. PMID:21173154

  5. Growth of normal oral keratinocytes and squamous cell carcinoma cells in a novel protein-free defined medium

    Microsoft Academic Search

    Nobuyuki Kamata; Kazuhiro Yokoyama; Ryoichi Fujimoto; Naohiro Ueda; Eiji Hayashi; Hiroaki Nakanishi; Masaru Nagayama

    1999-01-01

    Summary  A novel protein-free synthetic medium was developed for the culture of normal human oral keratinocytes. This medium, designated\\u000a PFM-7, supports the serial cultivation of primary or secondary normal oral keratinocytes in protein-free, chemically defined\\u000a conditions. Normal oral keratinocytes in PFM-7 exhibited nearly equal growth in mass culture without noticeable changes in\\u000a morphology, response to added growth factors, or gene expression

  6. Hepatocyte Growth Factor Activator Inhibitor Type 1 Maintains the Assembly of Keratin into Desmosomes in Keratinocytes by Regulating Protease-Activated Receptor 2-Dependent p38 Signaling.

    PubMed

    Kawaguchi, Makiko; Kanemaru, Ai; Sawaguchi, Akira; Yamamoto, Koji; Baba, Takashi; Lin, Chen-Yong; Johnson, Michael D; Fukushima, Tsuyoshi; Kataoka, Hiroaki

    2015-06-01

    Hepatocyte growth factor activator inhibitor type 1 (HAI-1; official symbol SPINT1) is a membrane-associated serine proteinase inhibitor abundantly expressed in epithelial tissues. Genetically engineered mouse models demonstrated that HAI-1 is critical for epidermal function, possibly through direct and indirect regulation of cell surface proteases, such as matriptase and prostasin. To obtain a better understanding of the role of HAI-1 in maintaining epidermal integrity, we performed ultrastructural analysis of Spint1-deleted mouse epidermis and organotypic culture of an HAI-1 knockdown (KD) human keratinocyte cell line, HaCaT. We found that the aggregation of tonofilaments to desmosomes was significantly reduced in HAI-1-deficient mouse epidermis with decreased desmosome number. Similar findings were observed in HAI-1 KD HaCaT organotypic cultures. Immunoblot and immunohistochemical analyses revealed that p38 mitogen-activated protein kinase was activated in response to HAI-1 insufficiency. Treatment of HAI-1 KD HaCaT cells with a p38 inhibitor abrogated the above-observed ultrastructural abnormalities. The activation of p38 induced by the loss of HAI-1 likely resulted from enhanced signaling of protease-activated receptor-2 (PAR-2), because its silencing abrogated the enhanced activation of p38. Consequently, treatment of HAI-1 KD HaCaT cells with a serine protease inhibitor, aprotinin, or PAR-2 antagonist alleviated the abnormal ultrastructural phenotype in organotypic culture. These results suggest that HAI-1 may have a critical role in maintaining normal keratinocyte morphology through regulation of PAR-2-dependent p38 mitogen-activated protein kinase signaling. PMID:25842366

  7. Keratinocyte Growth Factor Gene Electroporation into Skeletal Muscle as a Novel Gene Therapeutic Approach for Elastase-Induced Pulmonary Emphysema in Mice.

    PubMed

    Tobinaga, Shuichi; Matsumoto, Keitaro; Nagayasu, Takeshi; Furukawa, Katsuro; Abo, Takafumi; Yamasaki, Naoya; Tsuchiya, Tomoshi; Miyazaki, Takuro; Koji, Takehiko

    2015-06-29

    Pulmonary emphysema is a progressive disease with airspace destruction and an effective therapy is needed. Keratinocyte growth factor (KGF) promotes pulmonary epithelial proliferation and has the potential to induce lung regeneration. The aim of this study was to determine the possibility of using KGF gene therapy for treatment of a mouse emphysema model induced by porcine pancreatic elastase (PPE). Eight-week-old BALB/c male mice treated with intra-tracheal PPE administration were transfected with 80 ?g of a recombinant human KGF (rhKGF)-expressing FLAG-CMV14 plasmid (pKGF-FLAG gene), or with the pFLAG gene expressing plasmid as a control, into the quadriceps muscle by electroporation. In the lung, the expression of proliferating cell nuclear antigen (PCNA) was augmented, and surfactant protein A (SP-A) and KGF receptor (KGFR) were co-expressed in PCNA-positive cells. Moreover, endogenous KGF and KGFR gene expression increased significantly by pKGF-FLAG gene transfection. Arterial blood gas analysis revealed that the PaO2 level was not significantly reduced on day 14 after PPE instillation with pKGF-FLAG gene transfection compared to that of normal mice. These results indicated that KGF gene therapy with electroporation stimulated lung epithelial proliferation and protected depression of pulmonary function in a mouse emphysema model, suggesting a possible method of treating pulmonary emphysema. PMID:26160987

  8. Keratinocyte Growth Factor Gene Electroporation into Skeletal Muscle as a Novel Gene Therapeutic Approach for Elastase-Induced Pulmonary Emphysema in Mice

    PubMed Central

    Tobinaga, Shuichi; Matsumoto, Keitaro; Nagayasu, Takeshi; Furukawa, Katsuro; Abo, Takafumi; Yamasaki, Naoya; Tsuchiya, Tomoshi; Miyazaki, Takuro; Koji, Takehiko

    2015-01-01

    Pulmonary emphysema is a progressive disease with airspace destruction and an effective therapy is needed. Keratinocyte growth factor (KGF) promotes pulmonary epithelial proliferation and has the potential to induce lung regeneration. The aim of this study was to determine the possibility of using KGF gene therapy for treatment of a mouse emphysema model induced by porcine pancreatic elastase (PPE). Eight-week-old BALB/c male mice treated with intra-tracheal PPE administration were transfected with 80 ?g of a recombinant human KGF (rhKGF)-expressing FLAG-CMV14 plasmid (pKGF-FLAG gene), or with the pFLAG gene expressing plasmid as a control, into the quadriceps muscle by electroporation. In the lung, the expression of proliferating cell nuclear antigen (PCNA) was augmented, and surfactant protein A (SP-A) and KGF receptor (KGFR) were co-expressed in PCNA-positive cells. Moreover, endogenous KGF and KGFR gene expression increased significantly by pKGF-FLAG gene transfection. Arterial blood gas analysis revealed that the PaO2 level was not significantly reduced on day 14 after PPE instillation with pKGF-FLAG gene transfection compared to that of normal mice. These results indicated that KGF gene therapy with electroporation stimulated lung epithelial proliferation and protected depression of pulmonary function in a mouse emphysema model, suggesting a possible method of treating pulmonary emphysema.

  9. AMPK regulation of the growth of cultured human keratinocytes

    SciTech Connect

    Saha, Asish K. [Endocrinology, Diabetes and Nutrition, Department of Medicine, Boston University School of Medicine, Boston, MA (United States)]. E-mail: aksaha@bu.edu; Persons, Kelly [Endocrinology, Diabetes and Nutrition, Department of Medicine, Boston University School of Medicine, Boston, MA (United States); Safer, Joshua D. [Endocrinology, Diabetes and Nutrition, Department of Medicine, Boston University School of Medicine, Boston, MA (United States); Luo Zhijun [Endocrinology, Diabetes and Nutrition, Department of Medicine, Boston University School of Medicine, Boston, MA (United States); Holick, Michael F. [Endocrinology, Diabetes and Nutrition, Department of Medicine, Boston University School of Medicine, Boston, MA (United States); Ruderman, Neil B. [Endocrinology, Diabetes and Nutrition, Department of Medicine, Boston University School of Medicine, Boston, MA (United States)

    2006-10-20

    AMP kinase (AMPK) is a fuel sensing enzyme that responds to cellular energy depletion by increasing processes that generate ATP and inhibiting others that require ATP but are not acutely necessary for survival. In the present study, we examined the relationship between AMPK activation and the growth (proliferation) of cultured human keratinocytes and assessed whether the inhibition of keratinocyte growth by vitamin D involves AMPK activation. In addition, we explored whether the inhibition of keratinocyte proliferation as they approach confluence could be AMPK-related. Keratinocytes were incubated for 12 h with the AMPK activator, 5-aminoimidazole-4-carboxamide-1-{beta}-D-ribofuranoside (AICAR). At concentrations of 10{sup -4} and 10{sup -3} M, AICAR inhibited keratinocyte growth by 50% and 95%, respectively, based on measurements of thymidine incorporation into DNA. It also increased AMPK and acetyl CoA carboxylase phosphorylation (P-AMPK and P-ACC) and decreased the concentration of malonyl CoA confirming that AMPK activation had occurred. Incubation with the thiazolidinedione, troglitazone (10{sup -6} M) caused similar alterations in P-AMPK, P-ACC, and cell growth. In contrast, the well known inhibition of keratinocyte growth by 1,25-dihydroxyvitamin D{sub 3} (10{sup -7} and 10{sup -6} M) was not associated with changes in P-AMPK or P-ACC. Like most cells, the growth of keratinocytes diminished as they approached confluence. Thus, it was of note that we found a progressive increase in P-AMPK (1.5- to 2-fold, p < 0.05) as keratinocytes grown in control medium went from 25% to 100% confluence. In conclusion, the data are consistent with the hypothesis that activation of AMPK acts as a signal to diminish the proliferation of cultured keratinocytes as they approach confluence. They also suggest that AMPK activators, such as AICAR and troglitazone, inhibit keratinocyte growth and that the inhibition of cell growth by 1,25-dihydroxyvitamin D{sub 3} is AMPK-independent.

  10. Relationship Between Cell-Associated Matrix Metalloproteinase 9 and Psoriatic Keratinocyte Growth

    Microsoft Academic Search

    Nathalie Buisson-Legendre; Hervé Emonard; Philippe Bernard; William Hornebeck

    2000-01-01

    Primary cultures of psoriatic keratinocytes proliferated at a higher rate and produced lower amounts of matrix metalloproteinase 9 than normal keratinocytes cultured under similar conditions. Supplementation of psoriatic keratinocyte cell culture medium with batimastat or the use of a matrix metalloproteinase 9 blocking antibody further stimulated psoriatic keratinocyte growth. An increase in intracellular ceramide level enhanced matrix metalloproteinase 9 production

  11. Identification of Keratinocyte Growth Factor as a Target of microRNA-155 in Lung Fibroblasts: Implication in Epithelial-Mesenchymal Interactions

    PubMed Central

    Chevalier, Benoit; Puisségur, Marie-Pierre; Lebrigand, Kevin; Robbe-Sermesant, Karine; Bertero, Thomas; Lino Cardenas, Christian L.; Courcot, Elisabeth; Rios, Géraldine; Fourre, Sandra; Lo-Guidice, Jean-Marc; Marcet, Brice; Cardinaud, Bruno; Barbry, Pascal; Mari, Bernard

    2009-01-01

    Background Epithelial-mesenchymal interactions are critical in regulating many aspects of vertebrate embryo development, and for the maintenance of homeostatic equilibrium in adult tissues. The interactions between epithelium and mesenchyme are believed to be mediated by paracrine signals such as cytokines and extracellular matrix components secreted from fibroblasts that affect adjacent epithelia. In this study, we sought to identify the repertoire of microRNAs (miRNAs) in normal lung human fibroblasts and their potential regulation by the cytokines TNF-?, IL-1? and TGF-?. Methodology/Principal Findings MiR-155 was significantly induced by inflammatory cytokines TNF-? and IL-1? while it was down-regulated by TGF-?. Ectopic expression of miR-155 in human fibroblasts induced modulation of a large set of genes related to “cell to cell signalling”, “cell morphology” and “cellular movement”. This was consistent with an induction of caspase-3 activity and with an increase in cell migration in fibroblasts tranfected with miR-155. Using different miRNA bioinformatic target prediction tools, we found a specific enrichment for miR-155 predicted targets among the population of down-regulated transcripts. Among fibroblast-selective targets, one interesting hit was keratinocyte growth factor (KGF, FGF-7), a member of the fibroblast growth factor (FGF) family, which owns two potential binding sites for miR-155 in its 3?-UTR. Luciferase assays experimentally validated that miR-155 can efficiently target KGF 3?-UTR. Site-directed mutagenesis revealed that only one out of the 2 potential sites was truly functional. Functional in vitro assays experimentally validated that miR-155 can efficiently target KGF 3?-UTR. Furthermore, in vivo experiments using a mouse model of lung fibrosis showed that miR-155 expression level was correlated with the degree of lung fibrosis. Conclusions/Significance Our results strongly suggest a physiological function of miR-155 in lung fibroblasts. Altogether, this study implicates this miRNA in the regulation by mesenchymal cells of surrounding lung epithelium, making it a potential key player during tissue injury. PMID:19701459

  12. A PKC-?\\/Fyn-Dependent Pathway Leading to Keratinocyte Growth Arrest and Differentiation

    Microsoft Academic Search

    Sara Cabodi; Enzo Calautti; Claudio Talora; Toshio Kuroki; Paul L. Stein; G. Paolo Dotto

    2000-01-01

    Growth control of epithelial cells differs substantially from other cell types. Activation of Fyn, a Src kinase family member, is required for normal keratinocyte differentiation. We report that increased Fyn activity by itself suppresses growth of keratinocytes, but not dermal fibroblasts, through downmodulation of EGF receptor (EGFR) signaling. Protein kinase C-? has also been implicated in keratinocyte growth\\/differentiation control. We

  13. Dyskeratosis Congenita Dermal Fibroblasts are Defective in Supporting the Clonogenic Growth of Epidermal Keratinocytes

    PubMed Central

    Buckingham, Erin M.; Goldman, Frederick D.; Klingelhutz, Aloysius J.

    2012-01-01

    Telomere shortening is associated with cellular senescence and aging. Dyskeratosis congenita (DC) is a premature aging syndrome caused by mutations in genes for telomerase components or telomere proteins. DC patients have very short telomeres and exhibit aging-associated pathologies including epidermal abnormalities and bone marrow failure. Here, we show that DC skin fibroblasts are defective in their ability to support the clonogenic growth of epidermal keratinocytes. Conditioned media transfer experiments demonstrated that this defect was largely due to lack of a factor or factors secreted from the DC fibroblasts. Compared to early passage normal fibroblasts, DC fibroblasts express significantly lower transcript levels of several genes that code for secreted proteins, including Insulin-like Growth Factor 1 (IGF1) and Hepatocyte Growth Factor (HGF). Aged normal fibroblasts with short telomeres also had reduced levels of IGF1 and HGF, similar to early passage DC fibroblasts. Knockdown of IGF1 or HGF in normal fibroblasts caused a reduction in the capacity of conditioned media from these fibroblasts to support keratinocyte clonogenic growth. Surprisingly, reconstitution of telomerase in DC fibroblasts did not significantly increase transcript levels of IGF1 or HGF or substantially increase the ability of the fibroblasts to support keratinocyte growth, indicating that the gene expression defect is not readily reversible. Our results suggest that telomere shortening in dermal fibroblasts leads to reduction in expression of genes such as IGF1 and HGF and that this may cause a defect in supporting normal epidermal proliferation. PMID:23251848

  14. Induction of ?Np63 by the Newly Identified Keratinocyte-Specific Transforming Growth Factor ? Signaling Pathway with Smad2 and I?B Kinase ? in Squamous Cell Carcinoma12

    PubMed Central

    Fukunishi, Nahoko; Katoh, Iyoko; Tomimori, Yoshiya; Tsukinoki, Keiichi; Hata, Ryu-Ichiro; Nakao, Atsuhito; Ikawa, Yoji; Kurata, Shun-ichi

    2010-01-01

    The expression of p63 (TP63/p51) occurs in the basal cells of stratified epithelia and is strongly enhanced at the early stages of squamous cell carcinomas (SCCs) of the head and neck, skin, cervix, and others. We analyzed a promoter/enhancer region (2k?N) that drives the predominant expression of ?Np63 for sensitivity to Smad signaling pathways. Reporter assays in HepG2 cells showed a moderate activation of 2k?N by Smad2 and I?B kinase ? (IKK?), partners of the newly identified keratinocyte-specific transforming growth factor ? (TGF-?) signaling, but not by other Smad molecules. In A431 cells, 2k?N was activated by Smad2 and IKK?, for which a Smad binding element (SMD2) at -204 was essential. Binding of Smad2 to the chromosomal SMD2 site was detectable. The association of Smad2 with IKK? was evident in the nucleus of A431, accounting for the enhancement of ?Np63 expression by TGF-?. Moreover, both ?Np63 and IKK? were necessary to maintain the noninvasive phenotype of this cell line. FaDu, an invasive, Smad4-deficient SCC, also allowed 2k?N transactivation by transfected Smad2 in the presence of endogenous IKK?. Reflecting the lack of chromosomal SMD2-Smad2 association and the absence of nuclear IKK?, however, endogenous ?Np63 was not controlled by TGF-? or IKK? in FaDu. SCC tissue arrays showed nuclear accumulation of IKK? and p63 intensification in well-differentiated noninvasive lesions. This study indicates that p63 is a target gene of the proposed keratinocyte-specific TGF-? signal pathway for suppression of the malignant conversion of SCC. PMID:21170261

  15. BAG-1 enhances cell-cell adhesion, reduces proliferation and induces chaperone-independent suppression of hepatocyte growth factor-induced epidermal keratinocyte migration

    SciTech Connect

    Hinitt, C.A.M.; Wood, J.; Lee, S.S. [Oral and Dental Science, University of Bristol, Lower Maudlin Street, Bristol, BS1 2LY (United Kingdom)] [Oral and Dental Science, University of Bristol, Lower Maudlin Street, Bristol, BS1 2LY (United Kingdom); Williams, A.C. [Cellular and Molecular Medicine, University of Bristol, School of Medical Sciences, University Walk, Bristol, BS8 1TD (United Kingdom)] [Cellular and Molecular Medicine, University of Bristol, School of Medical Sciences, University Walk, Bristol, BS8 1TD (United Kingdom); Howarth, J.L.; Glover, C.P.; Uney, J.B. [The Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol, BS1 3NY (United Kingdom)] [The Henry Wellcome Laboratories for Integrative Neuroscience and Endocrinology, University of Bristol, Dorothy Hodgkin Building, Whitson Street, Bristol, BS1 3NY (United Kingdom); Hague, A., E-mail: a.hague@bristol.ac.uk [Oral and Dental Science, University of Bristol, Lower Maudlin Street, Bristol, BS1 2LY (United Kingdom)

    2010-08-01

    Cell motility is important in maintaining tissue homeostasis, facilitating epithelial wound repair and in tumour formation and progression. The aim of this study was to determine whether BAG-1 isoforms regulate epidermal cell migration in in vitro models of wound healing. In the human epidermal cell line HaCaT, endogenous BAG-1 is primarily nuclear and increases with confluence. Both transient and stable p36-Bag-1 overexpression resulted in increased cellular cohesion. Stable transfection of either of the three human BAG-1 isoforms p36-Bag-1 (BAG-1S), p46-Bag-1 (BAG-1M) and p50-Bag-1 (BAG-1L) inhibited growth and wound closure in serum-containing medium. However, in response to hepatocyte growth factor (HGF) in serum-free medium, BAG-1S/M reduced communal motility and colony scattering, but BAG-1L did not. In the presence of HGF, p36-Bag-1 transfectants retained proliferative response to HGF with no change in ERK1/2 activation. However, the cells retained E-cadherin localisation at cell-cell junctions and exhibited pronounced cortical actin. Point mutations in the BAG domain showed that BAG-1 inhibition of motility is independent of its function as a chaperone regulator. These findings are the first to suggest that BAG-1 plays a role in regulating cell-cell adhesion and suggest an important function in epidermal cohesion.

  16. Expression of paired-like homeodomain transcription factor 2c (PITX2c) in epidermal keratinocytes

    SciTech Connect

    Shi, Ge [Department of Dermatology, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of) [Department of Dermatology, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of); Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of); Department of Dermatology, The First Affiliated Hospital, Guangxi Traditional Chinese Medical University, Guangxi, Nanning, 530023 (China); Sohn, Kyung-Cheol; Choi, Tae-Young; Choi, Dae-Kyoung; Lee, Sang-Sin [Department of Dermatology, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of) [Department of Dermatology, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of); Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of); Ou, Bai-sheng [Department of Dermatology, The First Affiliated Hospital, Guangxi Traditional Chinese Medical University, Guangxi, Nanning, 530023 (China)] [Department of Dermatology, The First Affiliated Hospital, Guangxi Traditional Chinese Medical University, Guangxi, Nanning, 530023 (China); Kim, Sooil; Lee, Young Ho [Department of Anatomy, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of)] [Department of Anatomy, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of); Yoon, Tae-Jin [Department of Dermatology, School of Medicine, Gyeongsang National University, Jinju, 660-702 (Korea, Republic of) [Department of Dermatology, School of Medicine, Gyeongsang National University, Jinju, 660-702 (Korea, Republic of); Institute of Health Sciences, School of Medicine, Gyeongsang National University, Jinju, 660-702 (Korea, Republic of); Kim, Seong-Jin [Department of Dermatology, Chonnam National University Medical School, Gwangju, 501-757 (Korea, Republic of)] [Department of Dermatology, Chonnam National University Medical School, Gwangju, 501-757 (Korea, Republic of); Lee, Young; Seo, Young-Joon; Lee, Jeung-Hoon [Department of Dermatology, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of) [Department of Dermatology, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of); Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of); Kim, Chang Deok, E-mail: cdkimd@cnu.ac.kr [Department of Dermatology, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of); Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, 301-747 (Korea, Republic of)

    2010-11-15

    Paired-like homeodomain transcription factor 2 (PITX2) has been implicated as one of the genes responsible for Rieger syndrome. It has been also shown to play a central role during development. In this study, we investigated the functional role of PITX2 in keratinocyte differentiation. RT-PCR analysis showed that PITX2c isoform was predominantly expressed in a differentiation-dependent manner. Consistent with, immunohistochemical staining showed that PITX2 expression was increased in the upper layer of epidermis. When PITX2c was overexpressed in cultured keratinocytes by a recombinant adenovirus, the differentiation markers such as involucrin and loricrin were significantly increased at both mRNA and protein levels. In addition, PITX2c overexpression led to the decrease of cell growth, concomitantly with the upregulation of cell cycle-related genes p21. To investigate the effect of PITX2c in vivo, we microinjected PITX2c expression vector into zebrafish embryo. Interestingly, overexpression of PITX2c in zebrafish embryo led to the formation of horn-like structure and thickening of epidermis, together with the increase of keratin 8 (K8) expression. These results suggest that PITX2c has a role in proliferation and differentiation of epidermal keratinocytes.

  17. Essential role of an activator protein-2 (AP-2)/specificity protein 1 (Sp1) cluster in the UVB-mediated induction of the human vascular endothelial growth factor in HaCaT keratinocytes.

    PubMed Central

    Brenneisen, Peter; Blaudschun, Ralf; Gille, Jens; Schneider, Lars; Hinrichs, Ralf; Wlaschek, Meinhard; Eming, Sabine; Scharffetter-Kochanek, Karin

    2003-01-01

    Chronic sun exposure of the skin has long been postulated to enhance cutaneous angiogenesis, resulting in highly vascularized skin cancers. As the UVB component of sunlight is a major contributor to photocarcinogenesis, we aimed to explore the effects of UVB radiation on vascular endothelial growth factor (VEGF) gene expression, using the immortalized keratinocyte cell line HaCaT as a model for transformed premalignant epithelial cells. In the present paper, we studied the molecular mechanism of UVB-induced VEGF providing a major angiogenic activity in tumour progression and invasion. After 12-24 h of UVB irradiation, a 2.4- to 2.7-fold increase in endogenous VEGF protein level was measured, correlating with an up to 2.5-fold induction of promoter-based reporter gene constructs of VEGF. Furthermore, we identified a GC-rich UVB-responsive region between -87 and -65 bp of the VEGF promoter. In electrophoretic mobility-shift assays, this region binds Sp1-dependent protein complexes constitutively and an additional UVB-inducible protein complex distinct from Sp1 protein. The transcription factor AP-2 (activator protein-2) was detected as a component of the UVB-inducible protein complex. The critical role of the AP-2/Sp1 (specificity protein 1) cluster was supported by demonstration of a significant reduction of UVB-mediated promoter activity upon deletion of this recognition site. The specificity of this region for UVB irradiation was demonstrated using PMA, which increased VEGF activity in HaCaT cells after transient transfection of the deleted promoter construct. In conclusion, our data clarified regulatory mechanisms of UVB-dependent VEGF stimulation which may be critical for angiogenic processes in the skin. PMID:12358602

  18. Interferon Regulatory Factor 6 is necessary but not sufficient for keratinocyte differentiation

    PubMed Central

    Biggs, Leah C.; Rhea, Lindsey; Schutte, Brian C.; Dunnwald, Martine

    2011-01-01

    Regulation of epidermal proliferation and differentiation is critical for maintenance of cutaneous homeostasis. Interferon Regulatory Factor 6 (Irf6) deficient mice die perinatally and exhibit ectopic proliferation and defective epidermal differentiation. We sought to determine if these disruptions of epidermal function were cell autonomous and used embryonic Irf6?/? keratinocytes to understand the specific role of Irf6 in keratinocyte proliferation and differentiation. In absence of Irf6, keratinocytes exhibited a heterogeneous phenotype with the presence of large cells. Irf6?/? keratinocytes displayed increased colony forming efficiency compared to wildtype cells, suggesting that Irf6 represses long-term proliferation. Irf6 was present at low levels in wildtype keratinocytes in culture and upregulated after induction of differentiation in vitro, along with upregulation of markers of early differentiation. However, Irf6?/? keratinocytes did not express markers of terminal differentiation. Overexpression of Irf6 in wildtype keratinocytes was insufficient to induce expression of markers of differentiation under growing conditions. Together, these results indicated that Irf6 is necessary, but not sufficient for keratinocyte differentiation. Finally, using a transgenic mouse expressing Lac-Z under the regulation of an enhancer element 9.7kb upstream of the Irf6 start site, we demonstrated that this element contributes to the regulation of Irf6 in the epidermis and keratinocytes in culture. PMID:21918538

  19. S100A11, an Dual Mediator for Growth Regulation of Human Keratinocytes

    PubMed Central

    Sakaguchi, Masakiyo; Sonegawa, Hiroyuki; Murata, Hitoshi; Kitazoe, Midori; Futami, Jun-ichiro; Kataoka, Ken; Yamada, Hidenori

    2008-01-01

    We previously revealed a novel signal pathway involving S100A11 for inhibition of the growth of normal human keratinocytes (NHK) caused by high Ca++ or transforming growth factor ?. Exposure to either agent resulted in transfer of S100A11 to nuclei, where it induced p21WAF1. In contrast, S100A11 has been shown to be overexpressed in many human cancers. To address this apparent discrepancy, we analyzed possible new functions of S100A11, and we provide herein evidence that 1) S100A11 is actively secreted by NHK; 2) extracellular S100A11 acts on NHK to enhance the production of epidermal growth factor family proteins, resulting in growth stimulation; 3) receptor for advanced glycation end products, nuclear factor-?B, Akt, and cAMP response element-binding protein are involved in the S100A11-triggered signal transduction; and 4) production and secretion of S100A11 are markedly enhanced in human squamous cancer cells. These findings indicate that S100A11 plays a dual role in growth regulation of epithelial cells. PMID:17978094

  20. microRNA-31/factor-inhibiting hypoxia-inducible factor 1 nexus regulates keratinocyte differentiation.

    PubMed

    Peng, Han; Kaplan, Nihal; Hamanaka, Robert B; Katsnelson, Julia; Blatt, Hanz; Yang, Wending; Hao, Liangliang; Bryar, Paul J; Johnson, Randall S; Getsios, Spiro; Chandel, Navdeep S; Lavker, Robert M

    2012-08-28

    Notch plays a critical role in the transition from proliferation to differentiation in the epidermis and corneal epithelium. Furthermore, aberrant Notch signaling is a feature of diseases like psoriasis, eczema, nonmelanoma skin cancer, and melanoma where differentiation and proliferation are impaired. Whereas much is known about the downstream events following Notch signaling, factors responsible for negatively regulating Notch receptor signaling after ligand activation are incompletely understood. Notch can undergo hydroxylation by factor-inhibiting hypoxia-inducible factor 1 (FIH-1); however, the biological significance of this phenomenon is unclear. Here we show that FIH-1 expression is up-regulated in diseased epidermis and corneal epithelium. Elevating FIH-1 levels in primary human epidermal keratinocytes (HEKs) and human corneal epithelial keratinocytes (HCEKs) impairs differentiation in submerged cultures and in a "three-dimensional" organotypic raft model of human epidermis, in part, via a coordinate decrease in Notch signaling. Knockdown of FIH-1 enhances keratinocyte differentiation. Loss of FIH-1 in vivo increased Notch activity in the limbal epithelium, resulting in a more differentiated phenotype. microRNA-31 (miR-31) is an endogenous negative regulator of FIH-1 expression that results in keratinocyte differentiation, mediated by Notch activation. Ectopically expressing miR-31 in an undifferentiated corneal epithelial cell line promotes differentiation and recapitulates a corneal epithelium in a three-dimensional raft culture model. Our results define a previously unknown mechanism for keratinocyte fate decisions where Notch signaling potential is, in part, controlled through a miR-31/FIH-1 nexus. PMID:22891326

  1. The effect of different biologic and biosynthetic wound covers on keratinocyte growth, stratification and differentiation in vitro

    PubMed Central

    Mestak, Ondrej

    2014-01-01

    The purpose of this study was to compare, by means of in vitro cultivation technique, five marketed brands of wound covers used in the treatment of burns and other skin defects (Biobrane®, Suprathel®, Veloderm®, Xe-Derma®, and Xenoderm®) for their ability to stimulate the keratinocyte growth, stratification, and differentiation. In three independent experiments, human keratinocytes were grown on the tested covers in organotypic cultures by the 3T3 feeder layer technique. Vertical paraffin sections of the wound covers with keratinocytes were processed using hematoxylin–eosin staining and immunostaining for involucrin. Keratinocyte populations on the dressings were assessed for (1) number of keratinocyte strata (primary variable), (2) quantitative growth, (3) thickness of the keratinocyte layer, and (4) cell differentiation. The Xe-Derma wound cover provided the best support to keratinocyte proliferation and stratification, with the number of keratinocyte strata significantly (p?keratinocyte proliferation and stratification. The distinctive position of Xe-Derma may be related to its composition, where natural dermal fibers form a smooth surface, similar to the basement membrane. Furthermore, the results indicate that in vitro evaluation of effects on epithelial growth may accelerate the development of new bio-engineering-based wound covers. PMID:25383177

  2. The effect of different biologic and biosynthetic wound covers on keratinocyte growth, stratification and differentiation in vitro

    PubMed Central

    Mestak, Ondrej

    2014-01-01

    The purpose of this study was to compare, by means of in vitro cultivation technique, five marketed brands of wound covers used in the treatment of burns and other skin defects (Biobrane®, Suprathel®, Veloderm®, Xe-Derma®, and Xenoderm®) for their ability to stimulate the keratinocyte growth, stratification, and differentiation. In three independent experiments, human keratinocytes were grown on the tested covers in organotypic cultures by the 3T3 feeder layer technique. Vertical paraffin sections of the wound covers with keratinocytes were processed using hematoxylin–eosin staining and immunostaining for involucrin. Keratinocyte populations on the dressings were assessed for (1) number of keratinocyte strata (primary variable), (2) quantitative growth, (3) thickness of the keratinocyte layer, and (4) cell differentiation. The Xe-Derma wound cover provided the best support to keratinocyte proliferation and stratification, with the number of keratinocyte strata significantly (p?keratinocyte proliferation and stratification. The distinctive position of Xe-Derma may be related to its composition, where natural dermal fibers form a smooth surface, similar to the basement membrane. Furthermore, the results indicate that in vitro evaluation of effects on epithelial growth may accelerate the development of new bio-engineering-based wound covers.

  3. PKC? mediates TGF?-induced growth inhibition of human keratinocytes via phosphorylation of S100C/A11

    PubMed Central

    Sakaguchi, Masakiyo; Miyazaki, Masahiro; Sonegawa, Hiroyuki; Kashiwagi, Mariko; Ohba, Motoi; Kuroki, Toshio; Namba, Masayoshi; Huh, Nam-ho

    2004-01-01

    Growth regulation of epithelial cells is of major concern because most human cancers arise from them. We demonstrated previously a novel signal pathway involving S100C/A11 for high Ca2+-induced growth inhibition of normal human keratinocytes (Sakaguchi, M., M. Miyazaki, M. Takaishi, Y. Sakaguchi, E. Makino, N. Kataoka, H. Yamada, M. Namba, and N.H. Huh. 2003. J. Cell Biol. 163:825–835). This paper addresses a question whether transforming growth factor ? (TGF?) shares the pathway with high Ca2+. On exposure of the cells to TGF?1, S100C/A11 was phosphorylated, bound to nucleolin, and transferred to the nucleus, resulting in induction of p21WAF1/CIP1 and p15INK4B through activation of Sp1. Protein kinase C ? (PKC?) was shown to phosphorylate 10Thr of S100C/A11, which is a critical event for the signal transduction. The TGF?1-induced growth inhibition was almost completely mitigated when PKC? activity was blocked or when S100C/A11 was functionally sequestered. These results indicate that, in addition to the well-characterized Smad-mediated pathway, the PKC?–S100C/A11-mediated pathway is involved in and essential for the growth inhibition of normal human keratinocytes cells by TGF?1. PMID:15051732

  4. Clonal growth of human keratinocytes with small amounts of dialyzed serum

    Microsoft Academic Search

    Donna M. Peehl; Richard G. Ham

    1980-01-01

    Summary  A survey of commercially availabla media revealed that medium F-12 was superior to medium 199 for clonal growth of human epidermal\\u000a keratinocytes (HK) when supplemented with 10 ?g\\/ml hydrocortisone (HC) plus dialyzed fetal bovine serum protein (FBSP), rather\\u000a than the whole serum used in previous studies. Qualitative and quantitative adjustment of the medium composition for optimal\\u000a clonal growth with minimal

  5. Effects of 1,25-dihydroxyvitamin D3 and its 20-epi analogues (MC 1288, MC 1301, KH 1060), on clonal keratinocyte growth: evidence for differentiation of keratinocyte stem cells and analysis of the modulatory effects of cytokines

    PubMed Central

    Gniadecki, Robert

    1997-01-01

    Keratinocytes are functionally divided into stem cells, transit amplifying cells and terminally differentiated cells. In a hyperproliferative skin disease, psoriasis, increased mitotic activity of the stem cells is chiefly responsible for epidermal hyperplasia. The effects of 1,25dihydroxyvitamin D3 (1,25(OH)2D3) and potent vitamin D3 analogues (MC 1288: 20-epi-1,25(OH)2D3, MC 1301: 20-epi-24a-homo-26,27-dimethyl-1,25(OH)2D3, KH 1060: 20-epi-22-oxa-24a-homo-26,27-dimethyl-1,25(OH)2D3) on the stem cells were investigated.Stem cells were identified retrospectively as those giving rise to large keratinocyte colonies in culture (holoclones). 1,25(OH)2D3 (10?8–10?6?M) suppressed formation of holoclones by stimulating the progenitor cell differentiation into the phenotype expressing differentiation markers (keratins K1/K10 and involucrin).20-Epi vitamin D3 analogues were more potent than 1,25(OH)2D3 in inhibiting the clonal keratinocyte growth. This activity correlated with the ability to induce cell differentiation (KH 1060>MC 1301>MC 1288>1,25(OH)2D3).Cytokines modulated the effects of 1,25(OH)2D3 on clonal growth. One of the following cytokines (epidermal growth factor, transforming growth factor ?, interleukin-1?, interleukin-1?, interleukin-6, interleukin-8) was required for 1,25(OH)2D3 to suppress clonal growth and induce cell differentiation. In contrast, keratinocyte growth factor and insulin-like growth factor I attenuated the effects of 1,25(OH)2D3.In conclusion, 1,25(OH)2D3 and 20-epi vitamin D3 analogues suppress clonal growth by directly inducing the differentiation of progenitor cells. It is conceivable that stimulation of stem cells differentiation is a major mechanism of action of vitamin D3 compounds in psoriasis. Balance between different types of cytokines in psoriatic epidermis may be an important factor determining the clinical effect of vitamin D-based therapy. PMID:9134225

  6. Fish oil constituent docosahexa-enoic acid selectively inhibits growth of human papillomavirus immortalized keratinocytes

    Microsoft Academic Search

    DaZhi Chen; Karen Auborn

    The omega-3-fatty acids inhibit proliferation of breast cancer cells whereas omega-6-fatty acids stimulate growth. In this study, we examined effects of these fatty acids on human pre-cancerous cells. Cervical keratinocytes, immortalized with the oncogenic human papillomavirus (HPV) type 16, were treated with linoleic acid, an omega- 6-fatty acid, and the omega-3-fatty acids, eicosapentaenoic and docosahexaenoic acids. Using both cell counts

  7. Tumor Necrosis Factor ? and Ultraviolet Radiation Are Potent Regulators of Human Keratinocyte ICAM-1 Expression

    Microsoft Academic Search

    Jean Krutmann; Andreas Köck; Elisabeth Schauer; Frauke Parlow; Annelie Möller; Alexander Kapp; Elisabeth Förster; Erwin Schöpf; Thomas A. Luger

    1990-01-01

    Intercellular adhesion molecule-1 (ICAM-1) functions as a ligand of leukocyte function-associated antigen-1 (LFA-1), as well as a receptor for human picorna virus, and its regulation thus affects various immunologic and inflammatory reactions. The weak, constitutive ICAM-1 expression on human keratinocytes (KC) can be up-regulated by cytokines such as interferon-gamma (IFN?) and tumor necrosis factor alpha (TNF?). In order to further

  8. Tumor necrosis factor beta and ultraviolet radiation are potent regulators of human keratinocyte ICAM-1 expression

    SciTech Connect

    Krutmann, J.; Koeck, A.S.; Schauer, E.; Parlow, F.; Moeller, A.K.; Kapp, A.; Foerster, E.S.; Schoepf, E.L.; Luger, T.A. (Univ. of Freiburg (Germany, F.R.))

    1990-08-01

    Intercellular adhesion molecule-1 (ICAM-1) functions as a ligand of leukocyte function-associated antigen-1 (LFA-1), as well as a receptor for human picorna virus, and its regulation thus affects various immunologic and inflammatory reactions. The weak, constitutive ICAM-1 expression on human keratinocytes (KC) can be up-regulated by cytokines such as interferon-gamma (IFN gamma) and tumor necrosis factor alpha (TNF alpha). In order to further examine the regulation of KC ICAM-1 expression, normal human KC or epidermoid carcinoma cells (KB) were incubated with different cytokines and/or exposed to ultraviolet (UV) radiation. Subsequently, ICAM-1 expression was monitored cytofluorometrically using a monoclonal anti-ICAM-1 antibody. Stimulation of cells with recombinant human (rh) interleukin (IL) 1 alpha, rhIL-4, rhIL-5, rhIL-6, rh granulocyte/macrophage colony-stimulating factor (GM-CSF), rh interferon alpha (rhIFN alpha), and rh transforming growth factor beta (TGF beta) did not increase ICAM-1 surface expression. In contrast, rhTNF beta significantly up-regulated ICAM-1 expression in a time- and dose-dependent manner. Moreover, the combination of rhTNF beta with rhIFN gamma increased the percentage of ICAM-1-positive KC synergistically. This stimulatory effect of rhTNF beta was further confirmed by the demonstration that rhTNF beta was capable of markedly enhancing ICAM-1 mRNA expression in KC. Finally, exposure of KC in vitro to sublethal doses of UV radiation (0-100 J/m2) prior to cytokine (rhIFN tau, rhTNF alpha, rhTNF beta) stimulation inhibited ICAM-1 up-regulation in a dose-dependent fashion. These studies identify TNF beta and UV light as potent regulators of KC ICAM-1 expression, which may influence both attachment and detachment of leukocytes and possibly viruses to KC.

  9. 55-kd Tumor Necrosis Factor Receptor Is Expressed by Human Keratinocytes and Plays a Pivotal Role in Regulation of Human Keratinocyte ICAM-1 Expression

    Microsoft Academic Search

    Uwe Trefzer; Manfred Brockhaus; Hansruedi Loetscher; Frauke Parlow; Alexander Kapp; Erwin Schöpf; Jean Krutmann

    1991-01-01

    Tumor necrosis factor ? (TNF?) is a potent modulator of human keratinocyte intercellular adhesion molecule-1 (ICAM-1) expression. TNF? is known to exert its biologic effects by binding to specific cell-surface receptors. Two distinct TNF binding molecules, the 55-kd and the 75-kd TNF receptor (TNFR) recently have been found to be expressed by human cells. These two receptor types are independently

  10. Alteration and Significance of Heparin-Binding Epidermal-Growth-Factor-Like Growth Factor in Psoriatic Epidermis

    Microsoft Academic Search

    Yan Zheng; Zhenhui Peng; Yili Wang; Shengshun Tan; Yanping Xi; Guorong Wang

    2003-01-01

    Background: Heparin-binding epidermal-growth-factor-like growth factor (HB-EGF) has proved to be a mitogen of keratinocytes, which may be involved in the pathogenesis of inflammatory diseases, but its mechanism in psoriasis remains unknown. Objective: To investigate the alteration of HB-EGF in the epidermis of active psoriasis vulgaris. Methods: The expression of HB-EGF in normal skin tissues, uninvolved tissues and psoriatic lesions was

  11. The 55-kD tumor necrosis factor receptor on human keratinocytes is regulated by tumor necrosis factor-alpha and by ultraviolet B radiation.

    PubMed Central

    Trefzer, U; Brockhaus, M; Lötscher, H; Parlow, F; Budnik, A; Grewe, M; Christoph, H; Kapp, A; Schöpf, E; Luger, T A

    1993-01-01

    In previous studies we showed that cultured human keratinocytes expressed the 55-kD TNF receptor (TNFR) and that its expression the important for TNF alpha-mediated upregulation of intercellular adhesion molecule-1 (ICAM-1) expression on keratinocytes. Because factors that either reduce or enhance TNFR expression are likely to have a major impact on the biological effects of TNF alpha on keratinocytes, these studies were conducted to determine the factors that regulate its expression on keratinocytes. Using reverse transcriptase polymerase chain reaction, human keratinocytes were shown to lack 75-kD TNFR expression, indicating that TNF responsiveness of human keratinocytes critically depended on regulation of 55-kD TNFR expression. Human keratinocyte 55-kD TNFR surface and mRNA expression was found to be regulated in vitro by recombinant human (rh) TNF alpha. Stimulation of keratinocytes with rhTNF alpha initially decreased, but later increased, 55-kD TNFR surface expression. This biphasic modulation of 55-kD TNFR surface expression was associated with concomitant changes in 55-kD TNFR mRNA expression. Ultraviolet B (UVB) radiation, a well-known inducer of synthesis and secretion of TNF alpha by human keratinocytes, was found to mimic TNF alpha-induced modulation of 55-kD TNFR surface and mRNA expression via a TNF alpha-mediated autocrine regulatory mechanism. Production of soluble 55-kD TNFR by human keratinocytes remained unaffected by TNF alpha stimulation or UVB irradiation. These studies provide clear evidence that membrane expression of the human 55-kD TNFR may be regulated in human keratinocytes by the ligand itself: TNF alpha. Since in previous studies UVB irradiation transiently inhibited TNF alpha-induced human keratinocyte ICAM-1 expression, it is proposed that UVB radiation-induced biphasic modulation of human keratinocyte 55-kD TNFR expression may affect the capacity of these cells to respond to TNF alpha. Images PMID:8392091

  12. UV-A-induced decrease in nuclear factor-kappaB activity in human keratinocytes.

    PubMed Central

    Djavaheri-Mergny, M; Gras, M P; Mergny, J L; Dubertret, L

    1999-01-01

    Previous reports have demonstrated an increase in nuclear factor-kappaB (NF-kappaB) activity in response to UV radiation. These studies have essentially focused on the DNA-damaging fraction of solar UV radiation (UV-B and UV-C). In contrast, the effects of UV-A radiation (320-400 nm) on NF-kappaB are not well known. In this study, we present evidence that UV-A radiation induces a marked decrease in NF-kappaB DNA-binding activity in NCTC 2544 human keratinocytes. In addition, NCTC 2544 keratinocytes pretreated with UV-A fail to respond to NF-kappaB inducers. Moreover, UV-A radiation induces a decrease in NF-kappaB-driven luciferase reporter gene expression in NCTC 2544 keratinocytes. The expression of the gene encoding IkappaBalpha (IkappaB is the NF-kappaB inhibitor), which is closely associated with NF-kappaB activity, is also reduced (3-fold) upon UV-A treatment. Our results indicate that the UV-A-induced decrease in NF-kappaB DNA-binding activity is associated with a decrease in the levels of the p50 and p65 protein subunits. This is the first evidence that an oxidative stress, such as UV-A radiation, may induce a specific decrease in NF-kappaB activity in mammalian cells, probably through degradation of NF-kappaB protein subunits. These findings suggest that UV-A could modulate the NF-kappaB-dependent gene expression. PMID:10051429

  13. Differential Distribution of Fibroblast Growth Factor (FGF)-7 and FGF10 in l-Arginine-Induced Acute Pancreatitis

    Microsoft Academic Search

    Toshiyuki Ishiwata; Zenya Naito; Yue Ping Lu; Kiyoko Kawahara; Takenori Fujii; Yoko Kawamoto; Kiyoshi Teduka; Yuichi Sugisaki

    2002-01-01

    There generative process of the pancreas after acute pancreatitis (AP) is characterized by acinar and ductal cell proliferation with synthesis and transient deposition of extracellular matrices. Various growth factors were reported to be highly expressed in AP, but their regulation has not yet been clarified. Fibroblast growth factor (FGF)-7, also known as keratinocyte growth factor (KGF), and FGF-10 are members

  14. Intracellular free calcium and growth changes in single human keratinocytes in response to vitamin D and five 20-epi-analogues

    Microsoft Academic Search

    K. T. Jones; G. R. Sharpe

    1994-01-01

    Vitamin D, 1,25(OH)2D3, decreases proliferation and promotes differentiation of keratinocytes, and other keratinocyte differentiation stimuli have been associated with an early rise in intracellular free calcium, [Ca2+]i. We therefore investigated the effect of 1,25(OH)2D3, its precursor D3 and five 20-epi-analogues (EB1089, KH1060, KH1139, MC1288, MC1301) on growth and [Ca2+]i levels of normal human keratinocytes. Cells were cultured in medium MCDB153

  15. CORONETTE KERATINOCYTE COLONY FORMATION IS SUPPORTED BY EPIDERMAL-DERMAL CELL INTERACTIONS IN THE BOVINE CLAW

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Delineating factors that orchestrate keratinocyte growth and differentiation in the claw is pivotal to understanding the quality of hoof horn production in health and disease. The specific objectives of this investigation were to establish an in vitro culture system for bovine coronette keratinocyt...

  16. Recombinant growth factors

    Microsoft Academic Search

    Lawrence T. Goodnough; Kenneth C. Anderson

    1995-01-01

    Recombinant human growth factors are expected to have a significant impact on the use of allogeneic blood components. For example, subsequent to the approval of recombinant human erythropoietin, blood transfusions in renal dialysis patients declined substantially.1 Likewise, myeloid growth factors have reduced infections and hospital stay by promoting hematologic recovery after high dose ablative chemotherapy. The high costs of these

  17. Xyloglucan from Tropaeolum majus Seeds Induces Cellular Differentiation of Human Keratinocytes by Inhibition of EGFR Phosphorylation and Decreased Activity of Transcription Factor CREB.

    PubMed

    Zacharski, Dominika M; Brandt, Simone; Esch, Stefan; König, Simone; Mormann, Michael; Ulrich-Merzenich, Gudrun; Hensel, Andreas

    2015-07-13

    Xyloglucan XG (molecular weight 462 kDa, 1,4-/1,4,6-(pGlc) linked backbone, side chains of 1-pXyl, 1,2-pXyl, 1-p-Gal) was isolated from the seeds of Tropaeolum majus. XG (100 ?g/mL) induced terminal cellular differentiation of human keratinocytes, as demonstrated by immunofluorescence staining and Western blot using cytokeratin 10 and involucrin as marker proteins. Differentiation was also induced by XG-derived oligosaccharides (degree of polymerization 7-9). Quantitative real-time polymerase chain reaction (qPCR) revealed the induction of gene expression of typical differentiation markers (cytokeratin, filaggrin, involucrin, loricrin, transglutaminase) in a time-dependent manner. Whole human genome microarray indicated that most of upregulated genes were related to differentiation processes. Microarray findings on selected genes were subsequently confirmed by qPCR. For identification of the molecular target of xyloglucan PAGE of keratinocyte membrane preparations was performed, followed by blotting with fluorescein isothiocyanate-labeled XG. XG interacting proteins were characterized by MS. Peptide fragments of epidermal growth factor receptor (EGFR) and integrin ?4 were identified. Subsequent phospho-kinase array indicated that phosphorylation of EGFR and transcription factor cAMP response element-binding protein (CREB) was decreased in the XG-treated cells. Thus, the XG-induced differentiation of keratinocytes is proposed to be mediated by the inhibition of the phosphorylation of EGFR, leading to a dimished CREB activation, which is essential for the activation of cellular differentiation. PMID:26068019

  18. Regulation of IL-33 expression by IFN-? and tumor necrosis factor-? in normal human epidermal keratinocytes.

    PubMed

    Meephansan, Jitlada; Tsuda, Hidetoshi; Komine, Mayumi; Tominaga, Shin-Ichi; Ohtsuki, Mamitaro

    2012-11-01

    IL-33, a member of the IL-1 family, is implicated in type 2 T helper cell immune reactions and acts as an "alarmin" to induce activation of dendritic cells in response to external stimuli. We investigated the effect of inflammatory cytokines on IL-33 expression in normal human epidermal keratinocytes. IFN-? dose- and time-dependently induced IL-33 expression in protein and mRNA; this was dependent on extracellular signal-regulated kinase, p38, EGFR, and JAK phosphorylation. Combined IFN-? and tumor necrosis factor (TNF)-? treatment induced expression of a 20-kDa band corresponding to mature IL-33, which was abolished by the addition of a calpain inhibitor. The addition of the inhibitor to IFN-? and TNF-?-stimulated cells also induced strong expression of a 25-kDa band. Small interference (si) RNA for IL-33 abolished expression of the smaller bands and the 30-kDa IL-33 band, suggesting that these IL-33 forms were IL-33 transcription products. Recombinant IL-33 added in the medium induced IL-8 production, and RNA knockdown by siRNA enhanced IL-8 expression, suggesting its dual role as a cytokine and a nuclear factor. These results indicate that IL-33 has a role in inflammatory skin diseases, in which IFN-? and TNF-? are present in high levels. PMID:22673732

  19. RXR? ablation in epidermal keratinocytes enhances UV radiation induced DNA damage, apoptosis, and proliferation of keratinocytes and melanocytes

    PubMed Central

    Wang, Zhixing; Coleman, Daniel J.; Bajaj, Gaurav; Liang, Xiaobo; Ganguli-Indra, Gitali; Indra, Arup Kumar

    2011-01-01

    We show here that keratinocytic nuclear receptor Retinoid X Receptor ? (RXR?) regulates mouse keratinocyte and melanocyte homeostasis following acute ultraviolet radiation (UVR). Keratinocytic RXR? has a protective role on UVR-induced keratinocyte and melanocyte proliferation/differentiation, oxidative stress mediated DNA damage and cellular apoptosis. We discovered that keratinocytic RXR? in a cell autonomous manner regulate mitogenic growth responses in skin epidermis via secretion of hbEGF, GMCSF, IL1-? and COX2, and activation of MAPK pathways. We identified altered expression of several keratinocyte-derived mitogenic paracrine growth factors such as ET-1, HGF, ?–MSH, SCF and FGF2 in skin of mice lacking RXR? in epidermal keratinocytes (RXR?ep?/? mice), which in a non-cell autonomous manner modulated melanocyte proliferation and activation after UVR. RXR?ep?/? mouse represents a unique animal model where UVR induces melanocyte proliferation/activation in both epidermis and dermis. Considered together, our results suggest that RXR antagonists, together with inhibitors of cell proliferation can be effective to prevent solar UV radiation induced photo-carcinogenesis. PMID:20944655

  20. Keratinocyte-Releasable Stratifin Functions as a Potent Collagenase-Stimulating Factor in Fibroblasts

    Microsoft Academic Search

    Aziz Ghahary; Feridoun Karimi-Busheri; Yvonne Marcoux; Yunyaun Li; Edward E. Tredget; Ruhangiz Taghi Kilani; Liang Li; Jing Zheng; Ali Karami; Bernd O. Keller; Michael Weinfeld

    2004-01-01

    Termination of wound healing requires a fine balance between collagen deposition and its hydrolysis. To dissect the underlying control mechanisms for this process, we established a keratinocyte\\/fibroblast co-culture system and subsequently demonstrated more than a 10-fold increase in collagenase expression in fibroblasts co-cultured with keratinocytes relative to that of control cells. This finding was further confirmed in fibroblasts grown in

  1. Tanshinone IIA Inhibits Growth of Keratinocytes through Cell Cycle Arrest and Apoptosis: Underlying Treatment Mechanism of Psoriasis.

    PubMed

    Li, Fu-Lun; Xu, Rong; Zeng, Qing-Chun; Li, Xin; Chen, Jie; Wang, Yi-Fei; Fan, Bin; Geng, Lin; Li, Bin

    2012-01-01

    The aim of the present investigation was to elucidate the cellular mechanisms whereby Tanshinone IIA (Tan IIA) leads to cell cycle arrest and apoptosis in vitro in keratinocytes, the target cells in psoriasis. Tan IIA inhibited proliferation of mouse keratinocytes in a dose- and time-dependent manner and induced apoptosis, resulting in S phase arrest accompanied by down-regulation of pCdk2 and cyclin A protein expression. Furthermore, Tan IIA-induced apoptosis and mitochondrial membrane potential changes were also further demonstrated by DNA fragmentation, single-cell gel electrophoresis assay (SCGE), and flow cytometry methods. Apoptosis was partially blocked by the caspase-3 inhibitor Ac-DEVD-CHO. Mitochondrial regulation of apoptosis further downstream was investigated, showing changes in the mitochondrial membrane potential, cytochrome c release into the cytoplasm, and enhanced activation of cleaved caspase-3 and Poly ADP-ribose polymerase (PARP). There was also no translocation of apoptosis-inducing factor (AIF) from mitochondria to the nucleus in apoptotic keratinocytes, indicating Tan IIA-induced apoptosis occurs mainly through the caspase pathway. Our findings provide the molecular mechanisms by which Tan IIA can be used to treat psoriasis and support the traditional use of Salvia miltiorrhiza Bungee (Labiatae) for psoriasis and related skin diseases. PMID:22203883

  2. New microbial growth factor.

    PubMed Central

    Bok, S H; Casida, L E

    1977-01-01

    A screening procedure was used to isolate from soil a Penicillium sp., two bacterial isolates, and a Streptomyces sp. that produced a new microbial growth factor. This factor was an absolute growth requirement for three soil bacteria. The Penicillium sp. and one of the bacteria requiring the factor, an Arthrobacter sp., were selected for more extensive study concerning the production and characteristics of the growth factor. It did not seem to be related to the siderochromes. It was not present in soil extract, rumen fluid, or any other medium component tested. It appears to be a glycoprotein of high molecular weight, and it has high specific activity. When added to the diets for a meadow vole mammalian test system, it caused an increased consumption of diet without a concurrent increase in rate of weight gain. PMID:327929

  3. Growth factors in haemopoiesis.

    PubMed

    Jones, A L; Millar, J L

    1989-01-01

    Haemopoietic growth factors have for over two decades allowed experimentalists to grow haemopoietic bone marrow cells in vitro. With refinements in technique and the discovery of novel growth factors, all of the known haemopoietic lineages can now be grown in vitro. This has allowed a much greater understanding of the complex process of haemopoiesis from the haemopoietic stem cell to the mature, functioning end-cell. The in vivo action of these growth factors has been harder to investigate. Although recombinant technology has afforded us the much greater quantities necessary for in vivo work, problems remain with administration because of effects on other tissues. Interpretation of results is difficult because of the complex inter-relationships which exist between factors. Some of these have been defined in vitro and it appears likely that they also operate in vivo. Erythropoietin is a physiological regulator of erythropoiesis. It has been detected in vivo with levels responding appropriately to stress (i.e. elevated in anaemia) and, when administered in pharmacological doses, has been shown to correct anaemia. Granulocyte/macrophage colony-stimulating factor (GM-CSF) has been detected in vivo and may influence the production and function of granulocytes and macrophages, although how it is regulated is unknown. Granulocyte colony-stimulating factor (G-CSF) and macrophage colony-stimulating factor are ore lineage-specific. Interleukin 3 (IL-3), although it has not been detected in vivo, may act on a primitive marrow precursor by expanding the population and making these cells more susceptible to other growth factors, such as GM-CSF. Interleukin 1 (IL-1) has been detected in vivo, does not appear to have any isolated action on bone marrow (except possibly radioprotection) but probably acts synergistically with other growth factors, such as G-CSF. Interleukins 2, 4, 5 and 6 have not been detected in vivo. All have effects on B-cells. In addition IL-2 is an essential factor for the in vitro growth of T-cells and may have antitumour effects in vivo. IL-5 is an eosinophil growth factor in vitro. Megakaryocytopoiesis is also affected by humoral factors. Factors, alone or in combination, may be useful to restore functional granulopoiesis when used therapeutically. Some can be used as anticancer agents, although there may be a risk of induction of haematological malignancy. Increased understanding of their physiological roles will allow a more rational use. PMID:2645965

  4. Role of Growth Factors, Cytokines, and Their Receptors in the Pathogenesis of Psoriasis

    Microsoft Academic Search

    James G. Krueger; Jeffrey F. Krane; D. Martin Carter; Alice B. Gottlieb

    1990-01-01

    Psoriasis is characterized by epidermal hyperplasia, altered epidermal maturation, and local accumulation of acute and chronic inflammatory cells. Keratinocyte hyperplasia in psoriasis may be explained in part by overproduction of growth factors or cytokines which stimulate epidermal proliferation and by altered metabolism of growth-factor receptors in affected skin. Psoriatic epidermis displays overproduction of TGF-alpha and interleukin-6 (IL-6), factors produced by

  5. Protection against mucosal injury by growth factors and cytokines.

    PubMed

    Booth, D; Potten, C S

    2001-01-01

    This article provides an overview of published studies in which growth factors and cytokines were used to modify the sensitivity of intestinal stem cells to a dose of radiation. In these experiments, growth factors were used to manipulate the sensitivity of stem cells in the gastrointestinal tract to reduce the severity of gastrointestinal mucositis in cancer therapy patients. Transforming growth factor beta3, interleukin 11, and keratinocyte growth factor were used. All three agents, given according to appropriate protocols, can result in a threefold to fourfold increase in the number of intestinal stem cells that survive a dose of radiation therapy. This result was assessed by using the crypt microcolony assay of stem cell functional capacity. The changes in stem cell survival that were observed resulted in increased animal survival. This increased survival was taken as a surrogate for improvement in patient well-being. The severity of diarrhea, a marker of functional impairment, was concomitantly reduced. PMID:11694560

  6. Growth of keratinocytes on porous films of poly(3-hydroxybutyrate) and poly(4-hydroxybutyrate) blended with hyaluronic acid and chitosan.

    PubMed

    Peschel, Gundela; Dahse, Hans-Martin; Konrad, Anke; Wieland, Gerhard Dieter; Mueller, Peter-Juergen; Martin, David P; Roth, Martin

    2008-06-15

    The objective of this study was to develop novel absorbable films suitable for use as a tissue-engineering scaffold for keratinocytes as a therapy for replacement of damaged skin. Poly(4-hydroxybutyrate) (P(4HB)) and poly (3-hydroxybutyrate) (P(3HB)) were blended with small amounts of the polysaccharides hyaluronic acid (HA), chitosan (CH), pectin and alginic acid, and were solution cast to produce porous films. The resulting composites had favorable mechanical properties, and these films were compared with two commercially available implantable films made of poly(L-lactide-co-D,L-lactide) (PLA copolymer) and HA benzyl ester. Tensile testing demonstrated that a high level of flexibility of P(4HB) was retained in the P(4HB)-polysaccharide composite films, whereas the P(3HB) film and its polysaccharide composites were stiffer and more brittle. The proliferation kinetics of adherent HaCaT keratinocytes on the films was examined in vitro. The porous surface of the P(4HB) and P(3HB) films blended with HA or CH promoted the growth of keratinocytes significantly. The order of maximum cell numbers on these films was P(4HB)/HA > P(4HB)/CH > P(3HB)/HA > P(3HB)/CH > P(3HB)/pectin > P(3HB)/alginic acid. Scanning electron microscopy and confocal laser scanning microscopy revealed differences in cell growth. Cells formed clusters on P(3HB) and its composites, while the cells grew as a confluent layer on P(4HB) and its composites. HaCaT cells formed large numbers of filaments only on P(4HB) films, indicating the excellent biocompatibility of this material. For the nonporous PHB films, the proliferation rate of cells was found to increase with decreasing hydrophobicity in the order: P(4HB) > P(3HB)/P(4HB) blend > P(3HB). PMID:17937418

  7. Effect of Wnt3a on Keratinocytes Utilizing in Vitro and Bioinformatics Analysis

    PubMed Central

    Nam, Ju-Suk; Chakraborty, Chiranjib; Sharma, Ashish Ranjan; Her, Young; Bae, Kee-Jeong; Sharma, Garima; Doss, George Priya; Lee, Sang-Soo; Hong, Myung-Sun; Song, Dong-Keun

    2014-01-01

    Wingless-type (Wnt) signaling proteins participate in various cell developmental processes. A suppressive role of Wnt5a on keratinocyte growth has already been observed. However, the role of other Wnt proteins in proliferation and differentiation of keratinocytes remains unknown. Here, we investigated the effects of the Wnt ligand, Wnt3a, on proliferation and differentiation of keratinocytes. Keratinocytes from normal human skin were cultured and treated with recombinant Wnt3a alone or in combination with the inflammatory cytokine, tumor necrosis factor ? (TNF?). Furthermore, using bioinformatics, we analyzed the biochemical parameters, molecular evolution, and protein–protein interaction network for the Wnt family. Application of recombinant Wnt3a showed an anti-proliferative effect on keratinocytes in a dose-dependent manner. After treatment with TNF?, Wnt3a still demonstrated an anti-proliferative effect on human keratinocytes. Exogenous treatment of Wnt3a was unable to alter mRNA expression of differentiation markers of keratinocytes, whereas an altered expression was observed in TNF?-stimulated keratinocytes. In silico phylogenetic, biochemical, and protein–protein interaction analysis showed several close relationships among the family members of the Wnt family. Moreover, a close phylogenetic and biochemical similarity was observed between Wnt3a and Wnt5a. Finally, we proposed a hypothetical mechanism to illustrate how the Wnt3a protein may inhibit the process of proliferation in keratinocytes, which would be useful for future researchers. PMID:24686518

  8. Apoptosis is Initiated in Human Keratinocytes Exposed to Signalling Factors from Microbeam Irradiated Cells

    Microsoft Academic Search

    Fiona M. Lyng; Paula Maguire; A. Kilmurray; Carmel Mothersill; Chunlin Shao; Melvyn Folkard; Kevin M. Prise

    2006-01-01

    Purpose: There is now no doubt that bystander signalling from irradiated cells occurs and causes a variety of responses in cells not targeted by the ionising track. However, the mechanisms underlying these processes are unknown and the relevance to radiotherapy and risk assessment remains controversial. Previous research by our laboratory has shown bystander effects in a human keratinocyte cell line,

  9. Growth and differentiation of normal human melanocytes in a TPA-free, cholera toxin-free, low-serum medium and influence of keratinocytes

    Microsoft Academic Search

    P. Donatien; J. E. Surlève-Bazeille; A. J. Thody; A. TaÏeb

    1993-01-01

    Melanocyte cultures were obtained from a modification of the keratinocyte culture system MCDB153. Either promelanocytes or mature melanocytes were selected from epidermal cell primary cultures. Pure subcultures of actively dividing melanocytes of both types were grown in a low-serum medium totally deprived of TPA and cholera toxin called melanocyte growth medium (MGM). Early passaged cells from MGM primary cocultures were

  10. Protein Kinase C ? Increases Kruppel-like Factor 4 Protein, which Drives Involucrin Gene Transcription in Differentiating Keratinocytes*

    PubMed Central

    Chew, Yap Ching; Adhikary, Gautam; Xu, Wen; Wilson, Gerald M.; Eckert, Richard L.

    2013-01-01

    KLF4 is a member of the Kruppel-like factor family of transcriptional regulators. KLF4 has been shown to be required for normal terminal differentiation of keratinocytes, but the molecular mechanism whereby KLF4 regulates genes associated with the differentiation process has not been studied. In the present study, we explore the impact of KLF4 on expression of involucrin, a gene that is specifically expressed in differentiated keratinocytes. KLF4 overexpression and knockdown studies show that involucrin mRNA and protein level correlates directly with KLF4 level. Moreover, studies of mutant KLF4 proteins indicate that transcriptionally inactive forms do not increase involucrin expression. PKC? is a regulator of keratinocyte differentiation that increases expression of differentiation-associated target genes, including involucrin. Overexpression of KLF4 augments the PKC?-dependent increase in involucrin expression, whereas KLF4 knockdown attenuates this response. The KLF4 induction of human involucrin (hINV) promoter activity is mediated via KLF4 binding to a GC-rich element located in the hINV promoter distal regulatory region, a region of the promoter required for in vivo involucrin expression. Mutation of the GC-rich element, an adjacent AP1 factor binding site, or both sites severely attenuates the response. Moreover, loss of KLF4 in an epidermal equivalent model of differentiation results in loss of hINV expression. These studies suggest that KLF4 is part of a multiprotein complex that interacts that the hINV promoter distal regulatory region to drive differentiation-dependent hINV gene expression in epidermis. PMID:23599428

  11. Human Papillomavirus (HPV) Type 18 Induces Extended Growth in Primary Human Cervical, Tonsillar, or Foreskin Keratinocytes More Effectively than Other High-Risk Mucosal HPVs?

    PubMed Central

    Lace, Michael J.; Anson, James R.; Klingelhutz, Aloysius J.; Lee, John H.; Bossler, Aaron D.; Haugen, Thomas H.; Turek, Lubomir P.

    2009-01-01

    Mucosal high-risk (HR) human papillomaviruses (HPVs) that cause cervical and other anogenital cancers also are found in ?25% of head and neck carcinomas (HNCs), especially those arising in the oropharynx and the tonsils. While many HR HPV types are common in anogenital cancer, over 90% of HPV-positive HNCs harbor HPV type 16 (HPV-16). Using a quantitative colony-forming assay, we compared the ability of full-length mucosal HPV genomes, i.e., the low-risk HPV-11 and HR HPV-16, -18, and -31, to persist in and alter the growth of primary human keratinocytes from the foreskin, cervix, and tonsils. The HR HPV types led to the formation of growing keratinocyte colonies in culture independent of the site of epithelial origin. However, HPV-18 induced colony growth in all keratinocytes >4-fold more effectively than HPV-16 or HPV-31 and >20-fold more efficiently than HPV-11 or controls. HPV-11-transfected or control colonies failed to expand beyond 32 to 36 population doublings postexplantation. In contrast, individual HR HPV-transfected clones exhibited no apparent slowdown of growth or “crisis,” and many maintained HPV plasmid persistence beyond 60 population doublings. Keratinocyte clones harboring extrachromosomal HR HPV genomes had shorter population doubling times and formed dysplastic stratified epithelia in organotypic raft cultures, mirroring the pathological features of higher-grade intraepithelial lesions, yet did not exhibit chromosomal instability. We conclude that, in culture, the HR HPV type, rather than the site of epithelial origin of the cells, determines the efficacy of inducing continued growth of individual keratinocytes, with HPV-18 being the most aggressive mucosal HR HPV type tested. PMID:19740985

  12. Plant polyphenols differentially modulate inflammatory responses of human keratinocytes by interfering with activation of transcription factors NF{kappa}B and AhR and EGFR-ERK pathway

    SciTech Connect

    Potapovich, Alla I. [Tissue Engineering and Skin Pathophysiology Laboratory, Dermatology Research Institute (IDI IRCCS), Via Monti di Creta 104, Rome 00167 (Italy); Biology Department, Belarus State University, Skorina Prosp. 10, Minsk 220050 (Belarus); Lulli, Daniela; Fidanza, Paolo [Tissue Engineering and Skin Pathophysiology Laboratory, Dermatology Research Institute (IDI IRCCS), Via Monti di Creta 104, Rome 00167 (Italy); Kostyuk, Vladimir A. [Tissue Engineering and Skin Pathophysiology Laboratory, Dermatology Research Institute (IDI IRCCS), Via Monti di Creta 104, Rome 00167 (Italy); Biology Department, Belarus State University, Skorina Prosp. 10, Minsk 220050 (Belarus); De Luca, Chiara; Pastore, Saveria [Tissue Engineering and Skin Pathophysiology Laboratory, Dermatology Research Institute (IDI IRCCS), Via Monti di Creta 104, Rome 00167 (Italy); Korkina, Liudmila G., E-mail: l.korkina@idi.it [Tissue Engineering and Skin Pathophysiology Laboratory, Dermatology Research Institute (IDI IRCCS), Via Monti di Creta 104, Rome 00167 (Italy)

    2011-09-01

    Molecular mechanisms underlying modulation of inflammatory responses in primary human keratinocytes by plant polyphenols (PPs), namely the glycosylated phenylpropanoid verbascoside, the stilbenoid resveratrol and its glycoside polydatin, and the flavonoid quercetin and its glycoside rutin were evaluated. As non-lethal stimuli, the prototypic ligand for epidermal growth factor receptor (EGFR) transforming growth factor alpha (TGFalpha), the combination of tumor necrosis factor (TNFalpha) and interferon (IFNgamma) (T/I), UVA + UVB irradiation, and bacterial lipopolysaccharide (LPS) were used. We demonstrated differential modulation of inflammatory responses in keratinocytes at signal transduction, gene transcription, and protein synthesis levels as a function of PP chemical structure, the pro-inflammatory trigger used, and PP interaction with intracellular detoxifying systems. The PPs remarkably inhibited constitutive, LPS- and T/I-induced but not TGFalpha-induced ERK phosphorylation. They also suppressed NFkappaB activation by LPS and T/I. Verbascoside and quercetin invariably impaired EGFR phosphorylation and UV-associated aryl hydrocarbon receptor (AhR)-mediated signaling, while rutin, polydatin and resveratrol did not affect EGFR phosphorylation and further activated AhR machinery in UV-exposed keratinocytes. In general, PPs down-regulated gene expression of pro-inflammatory cytokines/enzymes, except significant up-regulation of IL-8 observed under stimulation with TGFalpha. Both spontaneous and T/I-induced release of IL-8 and IP-10 was suppressed, although 50 {mu}M resveratrol and polydatin up-regulated IL-8. At this concentration, resveratrol activated both gene expression and de novo synthesis of IL-8 and AhR-mediated mechanisms were involved. We conclude that PPs differentially modulate the inflammatory response of human keratinocytes through distinct signal transduction pathways, including AhR and EGFR. - Graphical abstract: Display Omitted Highlights: > Effects of plant polyphenols on inflammatory responses in human keratinocytes. > Inflammatory stimuli used: TGFalpha, TNFalpha+IFNgamma, UVA+UVB, and LPS. > Inflammatory pathways connected with NFB, ERK1/2, EGFR, and AhR were investigated. > Plant polyphenols, flavonoids, stilbenoids, and phenylpropanoids, were studied. > Modulation of inflammation depends on phenolic core structure and glycosylation.

  13. Functional Characterization of Cultured Keratinocytes after Acute Cutaneous Burn Injury

    PubMed Central

    Gauglitz, Gerd G.; Zedler, Siegfried; v. Spiegel, Felix; Fuhr, Jasmin; v. Donnersmarck, Guido Henkel; Faist, Eugen

    2012-01-01

    Background In addition to forming the epithelial barrier against the outside environment keratinocytes are immunologically active cells. In the treatment of severely burned skin, cryoconserved keratinocyte allografts gain in importance. It has been proposed that these allografts accelerate wound healing also due to the expression of a favourable - keratinocyte-derived - cytokine and growth factor milieu. Methods In this study the morphology and cytokine expression profile of keratinocytes from skin after acute burn injury was compared to non-burned skin. Skin samples were obtained from patients after severe burn injury and healthy controls. Cells were cultured and secretion of selected inflammatory mediators was quantified using Bioplex Immunoassays. Immunohistochemistry was performed to analyse further functional and morphologic parameters. Results Histology revealed increased terminal differentiation of keratinocytes (CK10, CK11) in allografts from non-burned skin compared to a higher portion of proliferative cells (CK5, vimentin) in acute burn injury. Increased levels of IL-1?, IL-2, IL-4, IL-10, IFN-? and TNF? could be detected in culture media of burn injury skin cultures. Both culture groups contained large amounts of IL-1RA. IL-6 and GM-CSF were increased during the first 15 days of culture of burned skin compared to control skin. Levels of VEGF, FGF-basic, TGF-ß und G-CSF were high in both but not significantly different. Cryoconservation led to a diminished mediator synthesis except for higher levels of intracellular IL-1? and IL-1ß. Conclusion Skin allografts from non-burned skin show a different secretion pattern of keratinocyte-derived cytokines and inflammatory mediators compared to keratinocytes after burn injury. As these secreted molecules exert auto- and paracrine effects and subsequently contribute to healing and barrier restoration after acute burn injury therapies affecting this specific cytokine/growth factor micromilieu could be beneficial in burned patients. PMID:22359539

  14. Asymmetric Migration of Human Keratinocytes under Mechanical Stretch and Cocultured Fibroblasts in a Wound Repair Model

    PubMed Central

    Lü, Dongyuan; Liu, Xiaofeng; Gao, Yuxin; Huo, Bo; Kang, Yingyong; Chen, Juan; Sun, Shujin; Chen, Li; Luo, Xiangdong; Long, Mian

    2013-01-01

    Keratinocyte migration during re-epithelization is crucial in wound healing under biochemical and biomechanical microenvironment. However, little is known about the underlying mechanisms whereby mechanical tension and cocultured fibroblasts or keratinocytes modulate the migration of keratinocytes or fibroblasts. Here we applied a tensile device together with a modified transwell assay to determine the lateral and transmembrane migration dynamics of human HaCaT keratinocytes or HF fibroblasts. A novel pattern of asymmetric migration was observed for keratinocytes when they were cocultured with non-contact fibroblasts, i.e., the accumulative distance of HaCaT cells was significantly higher when moving away from HF cells or migrating from down to up cross the membrane than that when moving close to HF cells or when migrating from up to down, whereas HF migration was symmetric. This asymmetric migration was mainly regulated by EGF derived from fibroblasts, but not transforming growth factor ? or ?1 production. Mechanical stretch subjected to fibroblasts fostered keratinocyte asymmetric migration by increasing EGF secretion, while no role of mechanical stretch was found for EGF secretion by keratinocytes. These results provided a new insight into understanding the regulating mechanisms of two- or three-dimensional migration of keratinocytes or fibroblasts along or across dermis and epidermis under biomechanical microenvironment. PMID:24086354

  15. Escape from Transforming Growth Factor beta Control and Oncogene Cooperation in Skin Tumor Development

    Microsoft Academic Search

    Caterina Missero; Santiago Ramon Y. Cajal; G. Paolo Dotto

    1991-01-01

    Control of tumor development by surrounding normal cells has been suggested by a number of in vitro studies. In vivo, tumorigenicity of ras-transformed primary keratinocytes can be suppressed by addition of normal dermal fibroblasts. Here, we report that dermal fibroblasts produce a diffusible inhibitory factor belonging to the transforming growth factor beta (TGF-beta) family and possibly corresponding to TGF-beta3. This

  16. Interleukin6 promotes human epidermal keratinocyte proliferation and keratin cytoskeleton reorganization in culture

    Microsoft Academic Search

    Miriam Hernández-Quintero; Walid Kuri-Harcuch; Arturo González Robles; Federico Castro-Muñozledo

    2006-01-01

    We have studied the effects of interleukin-6 (IL-6) on human epidermal keratinocytes by using serum-free culture conditions that allow the serial transfer, differentiation, and formation of well-organized multilayered epithelia. IL-6 at 2.5 ng\\/ml or higher concentrations promoted keratinocyte proliferation, with an ED50 of about 15 ng\\/ml and a maximum effect at 50 ng\\/ml. IL-6 was 10-fold less potent than epidermal growth factor (EGF)

  17. Hormones, growth factors and oncogenes

    SciTech Connect

    Pimentel, E.

    1987-01-01

    This book examines the hormones and peptide growth factors involved in the regulation of metabolism, growth and differentiation in metazoan organisms and proto-oncogene expression. It investigates protein products of some proto-oncogenes for involvement in the transductional and post-transductional and mechanisms of hormones and peptide growth factors.

  18. Activating transcription factor 3 (ATF3) expression is increased in erythema multiforme and is regulated by IFN-gamma in human keratinocytes.

    PubMed

    Pollack, Brian P; Sapkota, Bishu; Haun, Paul L

    2010-08-01

    Activating transcription factor 3 (ATF3) expression is increased in erythema multiforme and is regulated by IFN-gamma in human keratinocytes. Experimental Dermatology 2010; 19: e310-e313. Abstract: Activating transcription factor 3 (ATF3) is a member of the ATF/cyclic AMP responsive element-binding protein (CREB) family of transcription factors and is involved in the regulation of immune responses, apoptosis, DNA repair and oncogenesis. The epidermal expression of ATF3 in the setting of cutaneous inflammation has not been well characterized. To examine the expression of ATF3 in the setting of inflammatory skin disease, ATF3 protein expression was analysed by immunohistochemistry (IHC). We found diffuse epidermal ATF3 protein expression in skin biopsies of erythema multiforme (EM). Given the role of interferon (IFN)-gamma in erythema multiforme, we sought to examine the impact of IFN-gamma on ATF3 expression in human keratinocytes. IFN-gamma induced ATF3 mRNA and protein in primary human keratinocytes and HaCaT cells. Thus, epidermal ATF3 expression can be increased in the setting of inflammatory skin diseases and is regulated by IFN-gamma in human keratinocytes. PMID:20002170

  19. Wound Stimulation by Growth-Arrested Human Keratinocytes and Fibroblasts: HP802-247, a New-Generation Allogeneic Tissue Engineering Product

    Microsoft Academic Search

    René Goedkoop; Rodney Juliet; Percy Hou Kang You; Judit Daroczy; Kees-Peter de Roos; Raf Lijnen; Eric Rolland; Thomas Hunziker

    2010-01-01

    Background: HP802-247 is a new-generation, allogeneic tissue engineering product consisting of growth-arrested, human keratinocytes (K) and fibroblasts (F) delivered in a fibrin matrix by a spray device. Objective: To identify the preferred dose of HP802-247 based on cell concentration and K\\/F ratio. Methods: A multicenter, randomized, double-blind, placebo-controlled, explorative phase II study of 6 different doses of HP802-247 administered once

  20. Cox2 and ?-Catenin/T-cell Factor Signaling Intestinalize Human Esophageal Keratinocytes When Cultured under Organotypic Conditions12

    PubMed Central

    Kong, Jianping; Crissey, Mary Ann S; Stairs, Douglas B; Sepulveda, Antonia R; Lynch, John P

    2011-01-01

    The incidence of esophageal adenocarcinoma (EAC) is rising in the United States. An important risk factor for EAC is the presence of Barrett esophagus (BE). BE is the replacement of normal squamous esophageal epithelium with a specialized columnar epithelium in response to chronic acid and bile reflux. However, the emergence of BE from squamous keratinocytes has not yet been demonstrated. Our research has focused on this. Wnt and cyclooxygenase 2 (Cox2) are two pathways whose activation has been associated with BE and progression to EAC, but their role has not been tested experimentally. To explore their contribution, we engineered a human esophageal keratinocyte cell line to express either a dominant-active Wnt effector CatCLef or a Cox2 complementary DNA. In a two-dimensional culture environment, Cox2 expression increases cell proliferation and migration, but neither transgene induces known BE markers. In contrast, when these cells were placed into three-dimensional organotypic culture conditions, we observed more profound effects. CatCLef-expressing cells were more proliferative, developed a thicker epithelium, and upregulated Notch signaling and several BE markers including NHE2. Cox2 expression also increased cell proliferation and induced a thicker epithelium. More importantly, we observed cysts form within the epithelium, filled with intestinal mucins including Muc5B and Muc17. This suggests that Cox2 expression in a three-dimensional culture environment induces a lineage of mucin-secreting cells and supports an important causal role for Cox2 in BE pathogenesis. We conclude that in vitro modeling of BE pathogenesis can be improved by enhancing Wnt signaling and Cox2 activity and using three-dimensional organotypic culture conditions. PMID:21969813

  1. Fibroblast growth factor 23.

    PubMed

    Smith, Edward R; McMahon, Lawrence P; Holt, Stephen G

    2014-03-01

    There is growing interest in the role of fibroblast growth factor 23 (FGF23) in various diseases of disordered mineral metabolism. In chronic kidney disease (CKD), where biochemical evidence of mineral disturbances is especially common, FGF23 measurement has been advocated as an early and sensitive marker for CKD-related bone disease. In this setting, FGF23 analysis may also improve the discrimination of risk of adverse renal and cardiovascular outcomes and aid targeting of those patients that are likely to benefit from interventions. Nonetheless, while the physiological relevance of FGF23 in the control of mineral metabolism is now firmly established, relatively little attention has been paid to important preanalytical and analytical aspects of FGF23 measurement that may impact on its clinical utility. Here we review these issues and discuss the suitability of FGF23 testing strategies for routine clinical practice. The current 'state-of-the-art' enzyme-linked immunosorbent assay methods for FGF23 measurement show poor agreement due to differences in FGF23 fragment detection, antibody specificity and calibration. Such analytical variability does not permit direct comparison of FGF23 measurements made with different assays and is likely to at least in part account for some of the inconsistencies noted between observational studies. From a clinical perspective, the lack of concordance has implications for the development of standardized reference intervals and clinical decision limits. Finally, the inherent assay-dependent biological variability of plasma FGF23 concentration can further complicate the interpretation of results and the design of FGF23-based testing protocols. Currently, it would be premature to consider incorporating FGF23 measurements into standard testing repertoires. PMID:24269946

  2. Different Pathways Are Involved in Arsenic-Trioxide-Induced Cell Proliferation and Growth Inhibition in Human Keratinocytes

    Microsoft Academic Search

    X. Bi; J. Gu; Z. Guo; S. Tao; Y. Wang; L. Tang; J. Wu; Q. Mi

    2010-01-01

    Background: Arsenic is a carcinogen that is associated with an increased risk of human skin cancer. On the other hand, arsenic trioxide (As2O3) has potential anticancer activity against a wide range of carcinomas. The mechanisms involved in these two opposing processes remain unclear. Methods: We used normal human keratinocytes (NHK), the human keratinocyte HaCaT cell line and human epidermal carcinoma

  3. Kyolic® and Pycnogenol® increase human growth hormone secretion in genetically-engineered keratinocytes

    Microsoft Academic Search

    Amber R Buz'Zard; Qiaoling Peng; Benjamin H. S Lau

    2002-01-01

    The amount of human growth hormone (HGH) decreases significantly after the age of 30. This decrease has been implicated as one of the major causes in the signs of aging, such as thinning of the skin and bones, a decrease in lean muscle mass and an increase in adipose tissue. Supplementing the body's dwindling supply with recombinant human growth hormone

  4. Fibroblast growth factors in epithelial repair and cytoprotection.

    PubMed Central

    Braun, Susanne; auf dem Keller, Ulrich; Steiling, Heike; Werner, Sabine

    2004-01-01

    Growth factors are polypeptides that stimulate the division of certain cell types at low concentrations. Fibroblast growth factor (FGF) 7 (FGF-7) and its homologue FGF-10 act specifically on various types of epithelial cells including keratinocytes of the skin, intestinal epithelial cells and hepatocytes. In addition, FGF-7 and FGF-10 have been shown to be more than growth factors: they can protect epithelial cells from damaging effects induced, for example, by radiation and oxidative stress. Therefore, they are currently in clinical trials for the treatment of oral mucositis, a severe side-effect of cancer therapy characterized by painful inflammation and ulceration of the oral epithelium. To gain insight into the mechanisms of FGF-7/FGF-10 action in epithelial cells, we searched for genes that are regulated by these growth factors. Indeed, we identified genes that help us to explain the mechanisms that underlie the effects of FGF-7. Most interestingly, several genes were identified that are likely to mediate the cytoprotective effect of FGF-7 for epithelial cells in vitro and possibly also in injured and diseased tissues in vivo. PMID:15293802

  5. The Insulin-like Growth Factor 1 Receptor Is Expressed by Epithelial Cells with Proliferative Potential in Human Epidermis and Skin Appendages: Correlation of Increased Expression with Epidermal Hyperplasia

    Microsoft Academic Search

    Emmilia Hodak; Alice B. Gottlieb; Michele Anzilotti; James G. Krueger

    1996-01-01

    Ligand-mediated activation of the insulin-like growth factor 1 (IGF-1) receptor is critical for epidermal keratinocyte proliferation in vitro, and its expression in normal and psoriatic epidermis suggests that it might regulate keratinocyte proliferation in vivo. In this study, we used a monoclonal antibody (?-IR3) that binds to the ?-chain of this receptor to study its expression (1) in other epithelial

  6. Growth factors in ischemic stroke

    PubMed Central

    Lanfranconi, S; Locatelli, F; Corti, S; Candelise, L; Comi, G P; Baron, P L; Strazzer, S; Bresolin, N; Bersano, A

    2011-01-01

    Abstract Data from pre-clinical and clinical studies provide evidence that colony-stimulating factors (CSFs) and other growth factors (GFs) can improve stroke outcome by reducing stroke damage through their anti-apoptotic and anti-inflammatory effects, and by promoting angiogenesis and neurogenesis. This review provides a critical and up-to-date literature review on CSF use in stroke. We searched for experimental and clinical studies on haemopoietic GFs such as granulocyte CSF, erythropoietin, granulocyte-macrophage colony-stimulating factor, stem cell factor (SCF), vascular endothelial GF, stromal cell-derived factor-1? and SCF in ischemic stroke. We also considered studies on insulin-like growth factor-1 and neurotrophins. Despite promising results from animal models, the lack of data in human beings hampers efficacy assessments of GFs on stroke outcome. We provide a comprehensive and critical view of the present knowledge about GFs and stroke, and an overview of ongoing and future prospects. PMID:20015202

  7. Growth factors in synaptic function

    PubMed Central

    Poon, Vivian Y.; Choi, Sojoong; Park, Mikyoung

    2013-01-01

    Synapses are increasingly recognized as key structures that malfunction in disorders like schizophrenia, mental retardation, and neurodegenerative diseases. The importance and complexity of the synapse has fuelled research into the molecular mechanisms underlying synaptogenesis, synaptic transmission, and plasticity. In this regard, neurotrophic factors such as netrin, Wnt, transforming growth factor-? (TGF-?), tumor necrosis factor-? (TNF-?), and others have gained prominence for their ability to regulate synaptic function. Several of these factors were first implicated in neuroprotection, neuronal growth, and axon guidance. However, their roles in synaptic development and function have become increasingly clear, and the downstream signaling pathways employed by these factors have begun to be elucidated. In this review, we will address the role of these factors and their downstream effectors in synaptic function in vivo and in cultured neurons. PMID:24065916

  8. UV radiation and prostaglandin E2 up-regulate vascular endothelial growth factor (VEGF) in cultured human fibroblasts

    Microsoft Academic Search

    S. Trompezinski; I. Pernet; D. Schmitt; J. Viac

    2001-01-01

    Objective and Design: Exposure to UV radiation is responsible for skin erythema and inflammation. PGE2 is an important inflammatory mediator involved in this process and vascular endothelial growth factor (VEGF) is a potent vascular permeability factor mainly produced by epidermal keratinocytes. This study was aimed at determining whether UVB\\/A1 radiation and prostaglandin E2 (PGE2) could modulate the production of VEGF

  9. Role of p12(CDK2-AP1) in transforming growth factor-beta1-mediated growth suppression.

    PubMed

    Hu, Miaofen G; Hu, Guo-Fu; Kim, Yong; Tsuji, Takanori; McBride, Jim; Hinds, Philip; Wong, David T W

    2004-01-15

    p12(CDK2-AP1) (p12) is a growth suppressor isolated from normal keratinocytes. Ectopic expression of p12 in squamous carcinoma cells reversed the malignant phenotype of these cells, in part due an ability of p12 to bind to both DNA polymerase alpha/primase and to cyclin-dependent kinase 2 (CDK2), thereby inhibiting their activities. We report in this article that in normal epithelial cells, transforming growth factor beta1 (TGF-beta1) induces p12 expression transcriptionally, which, in turn, mediates the growth inhibitory activity of TGF-beta1. We created inducible p12 antisense HaCaT cell lines [ip12 (-) HaCaT] and showed that selective reduction of cellular p12 resulted in an increase in: (a) CDK2-associated kinase activity; (b) protein retinoblastoma (pRB) phosphorylation; and (c) [(3)H]thymidine incorporation, and partially reversed TGF-beta1-mediated inhibition of CDK2 kinase activity, pRB phosphorylation, and cell proliferation. Furthermore, we generated p12-deficient mouse oral keratinocytes (MOK(p12-/-)) and compared their growth characteristics and response to TGF-beta1 with that of wild-type mouse oral keratinocytes (MOK(WT)). Under normal culture conditions, the number of MOK(p12-/-) in S phase is 2-fold greater than that of MOK(WT). Concomitantly, fewer cells are in G(2) phase in MOK(p12-/-) than that in MOK(WT). Moreover, response to TGF-beta1-mediated growth suppression is compromised in MOK(p12-/-) cells. Mechanistic studies showed that MOK(p12-/-) have increased CDK2 activity and reduced sensitivity to inhibition by TGF-beta1. Collectively our data suggest that p12 plays a role in TGF-beta1-mediated growth suppression by modulating CDK2 activities and pRB phosphorylation. PMID:14744761

  10. Cyclic stretch induces upregulation of endothelin-1 with keratinocytes in vitro: Possible role in mechanical stress-induced hyperpigmentation

    SciTech Connect

    Kurita, Masakazu, E-mail: masakazukurita@gmail.com [Department of Plastic Surgery, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611 (Japan)] [Department of Plastic Surgery, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611 (Japan); Okazaki, Mutsumi [Department of Plastic and Reconstructive Surgery, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510 (Japan)] [Department of Plastic and Reconstructive Surgery, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510 (Japan); Fujino, Takashi [Department of Pathology, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611 (Japan)] [Department of Pathology, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611 (Japan); Takushima, Akihiko; Harii, Kiyonori [Department of Plastic Surgery, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611 (Japan)] [Department of Plastic Surgery, Kyorin University School of Medicine, 6-20-2 Shinkawa, Mitaka-shi, Tokyo 181-8611 (Japan)

    2011-05-27

    Highlights: {yields} Influence of cyclic stretch on melanogenetic paracrine cytokines was investigated. {yields} Keratinocyte-derived endothelin-1 was upregulated with cyclic stretch. {yields} Degree of upregulation increases dose-dependently. {yields} This upregulation possibly plays a role in the pathogenesis of pigmented disorders. -- Abstract: The aim of this study was to investigate the possible pathological relation between mechanical stress and hyperpigmentation. We did this by investigating the influence of cyclic stretch on the expression of keratinocyte- and fibroblast-derived melanogenetic paracrine cytokines in vitro. Using primary human keratinocytes and fibroblasts, alterations of mRNA expression of melanogenetic paracrine cytokines due to cyclic stretch were investigated using a real-time polymerase chain reaction (PCR). The cytokines included basic fibroblast growth factor (bFGF), stem cell factor (SCF), granulocyte/macrophage colony-stimulating factor, interleukin-1{alpha}, and endothelin-1 (ET-1) for keratinocytes and bFGF, SCF, and hepatocyte growth factor for fibroblasts. The dose dependence of keratinocyte-derived ET-1 upregulation was further investigated using real-time PCR and an enzyme-linked immunosorbent assay. We also investigated the effects of cyclic stretch on the proliferation and differentiation of keratinocytes. Among the melanogenetic paracrine cytokines investigated, keratinocyte-derived ET-1 was consistently upregulated in all four cell lines. The degree of upregulation increased with the degree of the length and frequency of the stretch; in contrast, cell number and differentiation markers showed no obvious alterations with cyclic stretch. Keratinocyte-derived ET-1 upregulation possibly plays a significant role in the pathogenesis of pigmented disorders, such as friction melanosis, caused by mechanical stress.

  11. Lysophosphatidic Acid Interacts with Transforming Growth Factor-? Signaling to Mediate Keratinocyte Growth Arrest and Chemotaxis

    Microsoft Academic Search

    Bettina Sauer; Rüdiger Vogler; Karsten Zimmermann; Makiko Fujii; Mario B. Anzano; Monika Schäfer-Korting; Anita B. Roberts; Burkhard Kleuser

    2004-01-01

    Lysophosphatidic acid (LPA, 1-acyl-glycerol-3-phosphate) plays an important role in diverse biological responses including cell proliferation, differentiation, survival, migration, and tumor cell invasion. The most prominent source of LPA is platelets from which it is released after thrombin activation and is assumed to be an essential function of this lysophospholipid in cutaneous wound closure. Therefore, we examined the role of LPA

  12. Production of interleukin-8 by human dermal fibroblasts and keratinocytes in response to interleukin-1 or tumour necrosis factor.

    PubMed Central

    Larsen, C G; Anderson, A O; Oppenheim, J J; Matsushima, K

    1989-01-01

    Cultured normal human fibroblasts were stimulated to produce neutrophil-activating protein/interleukin-8 (IL-8) in response to IL-1 alpha (0.1-1000 U/ml) or tumour necrosis factor (TNF) alpha (0.1-1000 U/ml). Induction of mRNA for IL-8 in fibroblasts was rapid (within 30 min) and maximal responses were obtained with either 100 U/ml IL-1 alpha or 100 U/ml TNF alpha. Expression of mRNA for IL-8 was accompanied by the production of high levels of neutrophil chemotactic activity. IL-1 alpha (1000 U/ml), but not TNF alpha, induced mRNA for IL-8 in cultured normal human keratinocytes. The relevance of production of IL-8 by these cell types was evaluated further by comparing the local inflammatory effects of IL-1 alpha, TNF alpha and IL-8. Intradermal injection of either recombinant IL-8, IL-1 alpha or TNF alpha lead to a similar in vivo effect, i.e. dose-dependent accumulation of lymphocytes and polymorphonuclear leucocytes at sites of injection. The in vivo attraction of neutrophils and lymphocytes to the site of injection by TNF or IL-1 (which is not chemotactic for neutrophils or lymphocytes in vitro), may be partly mediated by locally produced IL-8. Thus, IL-8 may be a vital participant in the cascade of interacting cytokines that is induced by tissue injury and immunologically induced inflammation. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:2478449

  13. Fetal fibroblasts and keratinocytes with immunosuppressive properties for allogeneic cell-based wound therapy.

    PubMed

    Zuliani, Thomas; Saiagh, Soraya; Knol, Anne-Chantal; Esbelin, Julie; Dréno, Brigitte

    2013-01-01

    Fetal skin heals rapidly without scar formation early in gestation, conferring to fetal skin cells a high and unique potential for tissue regeneration and scar management. In this study, we investigated the possibility of using fetal fibroblasts and keratinocytes to stimulate wound repair and regeneration for further allogeneic cell-based therapy development. From a single fetal skin sample, two clinical batches of keratinocytes and fibroblasts were manufactured and characterized. Tolerogenic properties of the fetal cells were investigated by allogeneic PBMC proliferation tests. In addition, the potential advantage of fibroblasts/keratinocytes co-application for wound healing stimulation has been examined in co-culture experiments with in vitro scratch assays and a multiplex cytokines array system. Based on keratin 14 and prolyl-4-hydroxylase expression analyses, purity of both clinical batches was found to be above 98% and neither melanocytes nor Langerhans cells could be detected. Both cell types demonstrated strong immunosuppressive properties as shown by the dramatic decrease in allogeneic PBMC proliferation when co-cultured with fibroblasts and/or keratinocytes. We further showed that the indoleamine 2,3 dioxygenase (IDO) activity is required for the immunoregulatory activity of fetal skin cells. Co-cultures experiments have also revealed that fibroblasts-keratinocytes interactions strongly enhanced fetal cells secretion of HGF, GM-CSF, IL-8 and to a lesser extent VEGF-A. Accordingly, in the in vitro scratch assays the fetal fibroblasts and keratinocytes co-culture accelerated the scratch closure compared to fibroblast or keratinocyte mono-cultures. In conclusion, our data suggest that the combination of fetal keratinocytes and fibroblasts could be of particular interest for the development of a new allogeneic skin substitute with immunomodulatory activity, acting as a reservoir for wound healing growth factors. PMID:23894651

  14. Internalization of Staphylococcus aureus by Human Keratinocytes

    PubMed Central

    Kintarak, Sompid; Whawell, Simon A.; Speight, Paul M.; Packer, Samantha; Nair, Sean P.

    2004-01-01

    Staphylococcus aureus is among the most important human pathogens and causes various superficial and systemic infections. The ability of S. aureus to be internalized by, and survive within, host cells, such as keratinocytes, may contribute to the development of persistent or chronic infections and may finally lead to deeper tissue infections or dissemination. To examine the mechanisms of internalization of S. aureus by keratinocytes, isogenic mutants lacking fibronectin-binding proteins (FnBPs), a recombinant protein consisting of the fibronectin-binding domain of S. aureus FnBPs, and an anti-?5?1 antibody were used in cocultures with immortalized keratinocytes and primary keratinocytes. We found that internalization of S. aureus by immortalized keratinocytes requires bacterial FnBPs and is mediated by the major fibronectin-binding integrin ?5?1. In contrast to internalization by immortalized keratinocytes, internalization of S. aureus by primary keratinocytes could occur through FnBP-dependent and -independent pathways. S. aureus clumping factor B (ClfB), which was recently determined to bind to epithelial cells, was not involved in the uptake of this bacterium by keratinocytes. The identification of an alternate uptake pathway, which is independent of S. aureus FnBPs and host cell ?5?1, has important implications for the design of therapies targeted to bacterial uptake by host cells. PMID:15385465

  15. Portulaca oleracea L. aids calcipotriol in reversing keratinocyte differentiation and skin barrier dysfunction in psoriasis through inhibition of the nuclear factor ?B signaling pathway

    PubMed Central

    ZHAO, HENGGUANG; LI, SHUANG; LUO, FULING; TAN, QIAN; LI, HUI; ZHOU, WEIKANG

    2015-01-01

    Psoriasis affects 2–4% of the population worldwide and its treatment is currently far from satisfactory. Calcipotriol and Portulaca oleracea have been reported to exhibit the capacity to inhibit inflammation in psoriatic patients and improve their clinical condition. However, the efficacy of a combination regimen of these two components remains unknown. The aim of the present study was to explore the therapeutic efficacy of P. oleracea extract combined with calcipotriol on plaque psoriasis and its potential mechanism. Eleven patients with plaque psoriasis were treated with humectant containing the active ingredients of P. oleracea extract, with or without 0.005% calcipotriol ointment in a right-left bilateral lesion self-control study. Differences were evaluated by investigation of the clinical efficacy, adverse effects, skin barrier function, histological structure, expression and proliferation of keratinocytes, differentiation markers (cytokeratin 10, filaggrin and loricrin), inflammatory factors [tumor necrosis factor (TNF)-? and interleukin (IL)-8], as well as the status of the nuclear factor ?B (NF-?B) pathway. The combination of P. oleracea and calcipotriol was revealed to decrease adverse effects, reduce transepidermal water loss, potently reverse keratinocyte differentiation dysfunction, and inhibit the expression of TNF-? and IL-8 and the phosphorylation of the NF-?B inhibitor I?B?. This treatment is therefore anticipated to be suitable for use as a novel adjuvant therapy for psoriatic patients. PMID:25574190

  16. Human papillomavirus causes an angiogenic switch in keratinocytes which is sufficient to alter endothelial cell behavior

    SciTech Connect

    Chen, W. [Department of Microbiology and Immunology and the Walther Oncology Center, Indiana University School of Medicine and the Walther Cancer Institute, Indianapolis, 635 Barnhill Drive, Indianapolis, IN 46202-5120 (United States); Li, F.; Mead, L.; White, H. [Department of Pediatrics, Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46202 (United States); Walker, J. [Department of Microbiology and Immunology and the Walther Oncology Center, Indiana University School of Medicine and the Walther Cancer Institute, Indianapolis, 635 Barnhill Drive, Indianapolis, IN 46202-5120 (United States); Ingram, D.A. [Department of Pediatrics, Herman B. Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN 46202 (United States); Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202 (United States); Roman, A. [Department of Microbiology and Immunology and the Walther Oncology Center, Indiana University School of Medicine and the Walther Cancer Institute, Indianapolis, 635 Barnhill Drive, Indianapolis, IN 46202-5120 (United States)], E-mail: aroman@iupui.edu

    2007-10-10

    One of the requirements for tumor growth is the ability to recruit a blood supply, a process known as angiogenesis. Angiogenesis begins early in the progression of cervical disease from mild to severe dysplasia and on to invasive cancer. We have previously reported that expression of human papillomavirus type 16 E6 and E7 (HPV16 E6E7) proteins in primary foreskin keratinocytes (HFKs) decreases expression of two inhibitors and increases expression of two angiogenic inducers [Toussaint-Smith, E., Donner, D.B., Roman, A., 2004. Expression of human papillomavirus type 16 E6 and E7 oncoproteins in primary foreskin keratinocytes is sufficient to alter the expression of angiogenic factors. Oncogene 23, 2988-2995]. Here we report that HPV-induced early changes in the keratinocyte phenotype are sufficient to alter endothelial cell behavior both in vitro and in vivo. Conditioned media from HPV16 E6E7 expressing HFKs as well as from human cervical keratinocytes containing the intact HPV16 were able to stimulate proliferation and migration of human microvascular endothelial cells. In addition, introduction of the conditioned media into immunocompetent mice using a Matrigel plug model resulted in a clear angiogenic response. These novel data support the hypothesis that HPV proteins contribute not only to the uncontrolled keratinocyte growth seen following HPV infection but also to the angiogenic response needed for tumor formation.

  17. Factors affecting growth factor activity in goat milk.

    PubMed

    Wu, F Y; Tsao, P H; Wang, D C; Lin, S; Wu, J S; Cheng, Y K

    2006-06-01

    Growth factors that are present in goat milk may be responsible for its beneficial effects on the digestive system as described in ancient Chinese medical texts. To develop a nutraceutical product rich in growth factors for promoting gastrointestinal health, it is essential to collect milk with consistently high growth factor activity. Therefore, we investigated the factors affecting growth factor activity in goat milk. Among the 5 breeds of dairy goats tested, milk from Nubian goats had the highest growth factor activity. Tight-junction leakage induced by a 24-h milking interval did not increase growth factor activity in the milk. Milk collected from pregnant does had a significantly higher growth factor activity than milk collected postpartum. Growth factor activity decreased during the first 8 wk of lactation, fluctuated thereafter, and then increased dramatically after natural mating. During wk 1 to 8, growth factor activity was inversely correlated with milk yield and week of lactation. No correlation was observed during wk 9 to 29. After natural mating of the goats, the growth factor activity in the milk correlated significantly with somatic cell count and conductivity (a measure of membrane permeability), and correlated inversely with milk yield. Based on the above data, goat milk with higher growth factor activity could be selectively collected from Nubian pregnant does. PMID:16702258

  18. Protein Kinase C (PKC) ? Suppresses Keratinocyte Proliferation by Increasing p21Cip1 Level by a KLF4 Transcription Factor-dependent Mechanism*

    PubMed Central

    Chew, Yap Ching; Adhikary, Gautam; Wilson, Gerald M.; Reece, E. Albert; Eckert, Richard L.

    2011-01-01

    PKC? increases keratinocyte differentiation and suppresses keratinocyte proliferation and survival. However, the mechanism of proliferation suppression is not well understood. The present studies show that PKC? overexpression increases p21Cip1 mRNA and protein level and promoter activity and that treatment with dominant-negative PKC?, PKC?-siRNA, or rottlerin inhibits promoter activation. Analysis of the p21Cip1 promoter upstream regulatory region reveals three DNA segments that mediate PKC?-dependent promoter activation. The PKC? response element most proximal to the transcription start site encodes six GC-rich DNA elements. Mutation of these sites results in a loss of PKC?-dependent promoter activation. Gel mobility supershift and chromatin immunoprecipitation reveal that these DNA elements bind the Kruppel-like transcription factor KLF4. PKC? increases KLF4 mRNA and protein level and KLF4 binding to the GC-rich elements in the p21Cip1 proximal promoter. In addition, KLF4-siRNA inhibits PKC?-dependent p21Cip1 promoter activity. PKC? increases KLF4 expression leading to enhanced KLF4 interaction with the GC-rich elements in the p21Cip1 promoter to activate transcription. PMID:21652709

  19. RIP2: A novel player in the regulation of keratinocyte proliferation and cutaneous wound repair?

    SciTech Connect

    Adams, Stephanie; Valchanova, Ralitsa S. [Charite-University Medicine Berlin, Institute of Physiology, Arnimallee 22, D-14195 Berlin (Germany)] [Charite-University Medicine Berlin, Institute of Physiology, Arnimallee 22, D-14195 Berlin (Germany); Munz, Barbara, E-mail: barbara.munz@charite.de [Charite-University Medicine Berlin, Institute of Physiology, Arnimallee 22, D-14195 Berlin (Germany)] [Charite-University Medicine Berlin, Institute of Physiology, Arnimallee 22, D-14195 Berlin (Germany)

    2010-03-10

    We could recently demonstrate an important role of receptor interacting protein 4 (RIP4) in the regulation of keratinocyte differentiation. Now, we analyzed a potential role of the RIP4 homolog RIP2 in keratinocytes. Specifically, we demonstrate here that rip2 expression is induced by scratch-wounding and after the induction of differentiation in these cells. Furthermore, serum growth factors and cytokines can induce rip2, with TNF-{alpha}-dependent induction being dependent on p38 MAPK. In addition, we demonstrate that scratch-induced upregulation of rip2 expression is completely blocked by the steroid dexamethasone. Since we also show that RIP2 is an important player in the regulation of keratinocyte proliferation, these data suggest that inhibition of rip2 upregulation after wounding might contribute to the reduced and delayed wound re-epithelialization phenotype seen in glucocorticoid-treated patients.

  20. Modulation of Ca2+ Levels in Keratinocytes by All-Trans Retinoic Acid

    Microsoft Academic Search

    James Varani; Dennis R. Inman; Douglas F. Gibbs; Suzanne E. G. Fligiel; John J. Voorhees

    1992-01-01

    Human epidermal keratinocytes, that have been growth-arrested by removal of epidermal growth factor from the culture medium, are stimulated to proliferate by all-trans retinoic acid (RA). The same treatment inhibits the onset of differentiated features and reduces cell-substrate adhesion. In the present study we show that the same treatment results in a decrease in total cell-associated Ca2+ as measured by

  1. Growth factors and antimicrobial factors of bovine colostrum

    Microsoft Academic Search

    R. Pakkanen; J. Aalto

    1997-01-01

    Colostrum is the first natural food produced by female mammals during the first 24–36h directly after giving birth. Chemically, colostrum is a very complex fluid rich in nutrients, antibodies and growth factors. In cows the antibodies provide passive immunity to the new born calf, whereas the growth factors especially stimulate the growth of the gut. The other antimicrobial components of

  2. Growth factor conjugation: strategies and applications.

    PubMed

    Hajimiri, Mirhamed; Shahverdi, Sheida; Kamalinia, Golnaz; Dinarvand, Rassoul

    2015-02-01

    Growth factors, first known for their essential role in the initiation of mitosis, are required for a variety of cellular processes and their localized delivery is considered as a rational approach in their therapeutic application to assure a safe and effective treatment while avoiding unwanted adverse effects. Noncovalent immobilization of growth factors as well as their covalent conjugation is amongst the most common strategies for localized delivery of growth factors. Today, immobilized and covalently conjugated growth factors are considered as a promising drug design and are widely used for protein reformulation and material design to cover the unwanted characteristics of growth factors as well as improving their functions. Selection of a suitable conjugation technique depends on the substrate chemistry and the availability of functional reactive groups in the structure of growth factor, the position of reactive groups in growth factor molecules and its relation with the receptor binding area, and the intention of creating either patterned or unpatterned conjugation. Various approaches for growth factor reformulation have been reported. This review provides an overview on chemical conjugation of growth factors and covers the relevant studies accomplished for bioconjugation of growth factors and their related application. PMID:24733811

  3. Adipose-derived stem cells and keratinocytes in a chronic wound cell culture model: the role of hydroxyectoine.

    PubMed

    Thamm, Oliver C; Theodorou, Panagiotis; Stuermer, Ewa; Zinser, Max J; Neugebauer, Edmund A; Fuchs, Paul C; Koenen, Paola

    2015-08-01

    Chronic wounds represent a major socio-economic problem in developed countries today. Wound healing is a complex biological process. It requires a well-orchestrated interaction of mediators, resident cells and infiltrating cells. In this context, mesenchymal stem cells and keratinocytes play a crucial role in tissue regeneration. In chronic wounds these processes are disturbed and cell viability is reduced. Hydroxyectoine (HyEc) is a membrane protecting osmolyte with protein and macromolecule stabilising properties. Adipose-derived stem cells (ASC) and keratinocytes were cultured with chronic wound fluid (CWF) and treated with HyEc. Proliferation was investigated using MTT test and migration was examined with transwell-migration assay and scratch assay. Gene expression changes of basic fibroblast growth factor (b-FGF), vascular endothelial growth factor (VEGF), matrix metalloproteinases-2 (MMP-2) and MMP-9 were analysed by quantitative real-time polymerase chain reaction (qRT-PCR). CWF significantly inhibited proliferation and migration of keratinocytes. Addition of HyEc did not affect these results. Proliferation capacity of ASC was not influenced by CWF whereas migration was significantly enhanced. HyEc significantly reduced ASC migration. Expression of b-FGF, VEGF, MMP-2 and MMP-9 in ASC, and b-FGF, VEGF and MMP-9 in keratinocytes was strongly induced by chronic wound fluid. HyEc enhanced CWF induced gene expression of VEGF in ASC and MMP-9 in keratinocytes. CWF negatively impaired keratinocyte function, which was not influenced by HyEc. ASC migration was stimulated by CWF, whereas HyEc significantly inhibited migration of ASC. CWF induced gene expression of VEGF in ASC and MMP-9 in keratinocytes was enhanced by HyEc, which might partly be explained by an RNA stabilising effect of HyEc. PMID:23841674

  4. Production of functional active human growth factors in insects used as living biofactories.

    PubMed

    Dudognon, Benoit; Romero-Santacreu, Lorena; Gómez-Sebastián, Silvia; Hidalgo, Ana B; López-Vidal, Javier; Bellido, María L; Muñoz, Eduardo; Escribano, José M

    2014-08-20

    Growth factors (GFs) are naturally signalling proteins, which bind to specific receptors on the cell surface. Numerous families of GFs have already been identified and remarkable progresses have been made in understanding the pathways that these proteins use to activate/regulate the complex signalling network involved in cell proliferation or wound healing processes. The bottleneck for a wider clinical and commercial application of these factors relay on their scalable cost-efficient production as bioactive molecules. The present work describes the capacity of Trichoplusia ni insect larvae used as living bioreactors in combination with the baculovirus vector expression system to produce three fully functional human GFs, the human epidermal growth factor (huEGF), the human fibroblast growth factor 2 (huFGF2) and the human keratinocyte growth factor 1 (huKGF1). The expression levels obtained per g of insect biomass were of 9.1, 2.6 and 3mg for huEGF, huFGF2 and huKGF1, respectively. Attempts to increase the productivity of the insect/baculovirus system we have used different modifications to optimize their production. Additionally, recombinant proteins were expressed fused to different tags to facilitate their purification. Interestingly, the expression of huKGF1 was significantly improved when expressed fused to the fragment crystallizable region (Fc) of the human antibody IgG. The insect-derived recombinant GFs were finally characterized in terms of biological activity in keratinocytes and fibroblasts. The present work opens the possibility of a cost-efficient and scalable production of these highly valuable molecules in a system that favours its wide use in therapeutic or cosmetic applications. PMID:24915129

  5. Smad7 Modulates Epidermal Growth Factor Receptor Turnover through Sequestration of c-Cbl.

    PubMed

    Ha Thi, Huyen Trang; Kim, Hye-Youn; Choi, Seo-Won; Kang, Jin-Muk; Kim, Seong-Jin; Hong, Suntaek

    2015-08-15

    Epidermal growth factor (EGF) regulates various cellular events, including proliferation, differentiation, migration, and tumorigenesis. For the maintenance of homeostasis, EGF signaling should be tightly regulated to prevent the aberrant activation. Smad7 has been known as inhibitory Smad that blocks the signal transduction of transforming growth factor ?. In the process of cell proliferation or transformation, Smad7 has been shown the opposite activities as a promoter or suppressor depending on cell types or microenvironments. We found that the overexpression of Smad7 in human HaCaT keratinocyte cells and mouse skin tissues elevated EGF receptor (EGFR) activity by impairing ligand-induced ubiquitination and degradation of activated receptor, which is induced by the E3 ubiquitin ligase c-Cbl. The C-terminal MH2 region but not MH1 region of Smad7 is critical for interaction with c-Cbl to inhibit the ubiquitination of EGFR. Interestingly, wild-type Smad7, but not Smad6 or mutant Smad7, destabilized the EGF-induced complex formation of c-Cbl and EGFR. These data suggest a novel role for Smad7 as a promoter for prolonging the EGFR signal in keratinocyte and skin tissue by reducing its ligand-induced ubiquitination and degradation. PMID:26055326

  6. Interleukin 1 binds to specific receptors on human keratinocytes and induces granulocyte macrophage colony-stimulating factor mRNA and protein. A potential autocrine role for interleukin 1 in epidermis.

    PubMed Central

    Kupper, T S; Lee, F; Birchall, N; Clark, S; Dower, S

    1988-01-01

    Cultured human keratinocytes have been shown to produce IL-1 alpha and beta mRNA and protein. IL-1 biological activity has been identified in normal human epidermis; in vitro, most biologically active IL-1 resides in a cell-associated compartment. The potential for autocrine effects of IL-1 on human keratinocytes was assessed by measurement of keratinocyte IL-1 receptors. Both high- and low-affinity cell surface receptors that bound recombinant (r) IL-1 alpha and beta with comparable affinities could be identified on cultured human keratinocytes, using 125I-labeled rIL-1. Chemical crosslinking experiments identified a cell surface molecule of roughly 72,500 Mr that bound 125I-labeled IL-1, similar to the molecular weight of previously described IL-1 receptors on fibroblasts, B cells, and T cells. To assess the biological consequences of keratinocyte IL-1 binding, granulocyte-macrophage colony-stimulating factor (GM-CSF) gene expression was measured. The addition of exogenous rIL-1 alpha led to a dose-dependent increase in the accumulation of GM-CSF mRNA, as measured by a sensitive and specific S1 nuclease assay. This increase in mRNA was reflected in a marked increase in GM-CSF biological activity as measured by proliferation of blast cells from chronic myelogenous leukemia patients. The biological activity was completely inhibitable by an antibody to human rGM-CSF. GM-CSF activates mature neutrophils and macrophages and appears to enhance the efficiency of Langerhans cell antigen presentation to T cells. Release of IL-1 from injured or activated keratinocytes may lead to enhanced epidermal GM-CSF gene expression via an autocrine mechanism, thus enhancing local host defense. Images PMID:2460504

  7. Dermal fibroblasts from venous ulcers are unresponsive to the action of transforming growth factor-? 1 1 Supported by grants from the National Institutes of Health (AR42936 and AG10998) and the Dermatology Foundation of Miami. 1

    Microsoft Academic Search

    Anthony Hasan; Hiroshi Murata; Anna Falabella; Sofia Ochoa; Linda Zhou; Evangelos Badiavas; Vincent Falanga

    1997-01-01

    Failure to reepithelialize is the major clinical problem in venous ulcers. It is not clear whether the problem resides with keratinocytes or with inadequate and improper formation of extracellular matrix. In this study, we characterized the biosynthetic activity and response to transforming growth factor-? 1 (TGF-?) of dermal fibroblast cultures isolated from biopsies of venous ulcers and from normal thigh

  8. Synthetic heparin-binding growth factor analogs

    DOEpatents

    Pena, Louis A.; Zamora, Paul; Lin, Xinhua; Glass, John D.

    2007-01-23

    The invention provides synthetic heparin-binding growth factor analogs having at least one peptide chain that binds a heparin-binding growth factor receptor, covalently bound to a hydrophobic linker, which is in turn covalently bound to a non-signaling peptide that includes a heparin-binding domain. The synthetic heparin-binding growth factor analogs are useful as soluble biologics or as surface coatings for medical devices.

  9. Growth factors, nutrient signaling, and cardiovascular aging

    PubMed Central

    Fontana, Luigi; Vinciguerra, Manlio; Longo, Valter D.

    2012-01-01

    Growth factors regulated by specific macronutrients have been shown to promote aging and accelerate mortality in the great majority of the organisms studied. In particular, the enzymes activated by growth hormone (GH), insulin and insulin-like growth factor 1 (IGF-I) in mammals and their orthologs in simple model organisms represent perhaps the best-understood proteins involved in the aging process. Dietary restriction (DR), which reduces the level of IGF-I and of other growth factors, has been associated with protection from diabetes, cancer, and cardiovascular diseases and deficiencies in GH signaling and IGF-I are strongly associated with protection from cancer and diabetes in both mice and humans, but their role in cardiac function and cardiovascular diseases is controversial. Here we review the link between growth factors, cardiac function and heart disease with focus on the cardioprotective and sensitizing effect of growth factors in both model organisms and humans. PMID:22499903

  10. Regulation of Growth Factor Receptors by Gangliosides

    NSDL National Science Digital Library

    Erik A. Miljan (Chicago; Children's Memorial Medical Center REV)

    2002-11-26

    Growth factor receptors are important in controlling many cellular functions, such as growth, differentiation, and disease. Growth factor receptors activate numerous signal transduction pathways within cells; however, how one growth factor receptor orchestrates multiple signal transduction pathways is not clear. This review focuses on a ubiquitous component of the plasma membrane, called "gangliosides," and how they modulate growth factor receptors at the cell membrane. Gangliosides are complex structures that consist of two parts--a lipid ceramide moiety and a carbohydrate head structure. Studies over the past two decades have demonstrated that different gangliosides can enhance or inhibit growth factor receptor activity. However, ganglioside modulation of growth factor receptors is more complex than simply stimulation or inhibition. We present and discuss three models of how gangliosides regulate growth factor receptors: (i) modulation of ligand binding, (ii) regulation of receptor dimerization, and (iii) regulation of receptor activation state and subcellular distribution. On the basis of these models, we speculate about the physiological consequences of ganglioside regulation of growth factor receptors.

  11. Roles for Growth Factors in Cancer Progression

    NSDL National Science Digital Library

    Esther Witsch (Weizmann Institute of Science)

    2010-04-01

    Under physiological conditions, cells receive fate-determining signals from their tissue surroundings, primarily in the form of polypeptide growth factors. Integration of these extracellular signals underlies tissue homeostasis. Although departure from homeostasis and tumor initiation are instigated by oncogenic mutations rather than by growth factors, the latter are the major regulators of all subsequent steps of tumor progression, namely clonal expansion, invasion across tissue barriers, angiogenesis, and colonization of distant niches. Here, we discuss the relevant growth factor families, their roles in tumor biology, as well as the respective downstream signaling pathways. Importantly, cancer-associated activating mutations that impinge on these pathways often relieve, in part, the reliance of tumors on growth factors. On the other hand, growth factors are frequently involved in evolvement of resistance to therapeutic regimens, which extends the roles for polypeptide factors to very late phases of tumor progression and offers opportunities for cancer therapy.

  12. Vascular endothelial growth factor, epidermal growth factor and fibroblast growth factor-4 and -10 stimulate trophoblast plasminogen activator system and metalloproteinase-9

    Microsoft Academic Search

    E. Y. Anteby; C. Greenfield; S. Natanson-Yaron; D. Goldman-Wohl; Y. Hamani; V. Khudyak; I. Ariel; S. Yagel

    2004-01-01

    Trophoblast invasion, accompanied by degradation of extracellular matrix, is crucial to normal pregnancy development, whereas shallow placental invasion and implantation likely plays a role in the subsequent development of pre-eclampsia. The growth factors vascular endothelial growth factor (VEGF), epidermal growth factor (EGF) and fibroblast growth factor (FGF) are placental growth factors that activate degradation of extracellular matrix. We determined the

  13. Hematopoietic growth factors in cancer treatment.

    PubMed

    Büchner, T

    1994-05-01

    The introduction of hematopoietic growth factors during the past five years has changed the scenery of antitumor treatment. Growth factors following high-dose chemotherapy or bone marrow transplantation have become established as part of many treatment protocols. The main benefits are earlier recovery of neutrophils resulting in fewer days with fever, antibiotics and hospitalization. Growth factors were found to reduce the treatment-related morbidity and to improve the practicability of therapeutic regimens. First studies on a prospective chemotherapy dose intensification supported by growth factors are underway. As a further effect of growth factors, an attempted enhancement of antitumor cytotoxicity by recruitment of tumor cells to chemosensitivity or by modulation of antitumor drug metabolism appears realistic based on first data on growth factor priming in AML. New ways to support high-intensity and myeloablative antitumor strategies are opened by the autologous transplantation of peripheral blood progenitor cells mobilized by growth factors and also by the use of new factors like SCF and the synergistic combination of growth factors as part of future strategies against malignant disorders. PMID:8075591

  14. Notch and TGF-? pathways cooperatively regulate receptor protein tyrosine phosphatase-? (PTPRK) gene expression in human primary keratinocytes.

    PubMed

    Xu, Yiru; Xue, Siliang; Zhou, Jin; Voorhees, John J; Fisher, Gary J

    2015-03-15

    Receptor protein tyrosine phosphatase-? (PTPRK) specifically and directly dephosphorylates epidermal growth factor receptor (EGFR), thereby limiting EGFR function in primary human keratinocytes. PTPRK expression is increased by the TGF-?/Smad3 pathway and cell-cell contact. Because the Notch receptor pathway is responsive to cell-cell contact and regulates keratinocyte growth and differentiation, we investigated the interplay between Notch and TGF-? pathways in regulation of PTPRK expression in human keratinocytes. Suppression of Notch signaling by ?-secretase inhibitors substantially reduced cell contact induction of PTPRK gene expression. In sparse keratinocyte cultures, addition of soluble Notch-activating ligand jagged one peptide (Jag1) induced PTPRK. Of interest, cell contact-induced expression of TGF-?1 and TGF-? receptor inhibitor SB431542 inhibited contact-induced expression of PTPRK. Furthermore, inhibition of Notch signaling, via knockdown of Notch1 or by ?-secretase inhibitors, significantly reduced TGF-?-induced PTPRK gene expression, indicating that Notch and TGF-? pathways function together to regulate PTPRK. Of importance, the combination of Jag1 plus TGF-? results in greater PTPRK expression and lower EGFR tyrosine phosphorylation than either ligand alone. These data indicate that Notch and TGF-? act in concert to stimulate induction of PTPRK, which suppresses EGFR activation in human keratinocytes. PMID:25609089

  15. Notch and TGF-? pathways cooperatively regulate receptor protein tyrosine phosphatase-? (PTPRK) gene expression in human primary keratinocytes

    PubMed Central

    Xu, Yiru; Xue, Siliang; Zhou, Jin; Voorhees, John J.; Fisher, Gary J.

    2015-01-01

    Receptor protein tyrosine phosphatase-? (PTPRK) specifically and directly dephosphorylates epidermal growth factor receptor (EGFR), thereby limiting EGFR function in primary human keratinocytes. PTPRK expression is increased by the TGF-?/Smad3 pathway and cell–cell contact. Because the Notch receptor pathway is responsive to cell–cell contact and regulates keratinocyte growth and differentiation, we investigated the interplay between Notch and TGF-? pathways in regulation of PTPRK expression in human keratinocytes. Suppression of Notch signaling by ?-secretase inhibitors substantially reduced cell contact induction of PTPRK gene expression. In sparse keratinocyte cultures, addition of soluble Notch-activating ligand jagged one peptide (Jag1) induced PTPRK. Of interest, cell contact–induced expression of TGF-?1 and TGF-? receptor inhibitor SB431542 inhibited contact-induced expression of PTPRK. Furthermore, inhibition of Notch signaling, via knockdown of Notch1 or by ?-secretase inhibitors, significantly reduced TGF-?–induced PTPRK gene expression, indicating that Notch and TGF-? pathways function together to regulate PTPRK. Of importance, the combination of Jag1 plus TGF-? results in greater PTPRK expression and lower EGFR tyrosine phosphorylation than either ligand alone. These data indicate that Notch and TGF-? act in concert to stimulate induction of PTPRK, which suppresses EGFR activation in human keratinocytes. PMID:25609089

  16. Release of growth factors after arthroscopic acromioplasty.

    PubMed

    Randelli, Pietro; Margheritini, Fabrizio; Cabitza, Paolo; Dogliotti, Giada; Corsi, Massimiliano M

    2009-01-01

    It has recently been postulated that a variety of growth factors may be released from cancellous bone after an acromioplasty. The aim of this study was to demonstrate the presence of growth factors in the subacromial space after acromioplasty. Between October 2006 and March 2007, 23 patients underwent arthroscopic acromioplasty. A sample of at least 3 ml of fluid from the shoulder was obtained 15 min after the end of the procedure. At the same time another sample of 3 ml of the patient's venous blood was obtained as a control. The concentrations of growth factors in the fluids collected were determined using enzyme-linked immunosorbent assay (ELISA). The growth factors assayed were platelet-derived growth factor-AB (PDGF-AB), basic fibroblast growth factor basic (bFGF) and transforming growth factor beta 1 (TGF-beta1). The concentrations of TGF-beta1 (p = 0.0001), PDGF-AB (p = 0.02), and bFGF (p < 0.0001) were significantly higher in the fluid from the subacromial space than in the blood sample. There are high concentrations of several growth factors in the subacromial space after acromioplasty. PMID:18974971

  17. Epidermal Growth Factor Receptor Immunohistochemistry

    PubMed Central

    Hirsch, Fred R.; Dziadziuszko, Rafal; Thatcher, Nick; Mann, Helen; Watkins, Claire; Parums, Dinah V.; Speake, Georgina; Holloway, Brian; Bunn, Paul A.; Franklin, Wilbur A.

    2012-01-01

    BACKGROUND The ISEL (Iressa Survival Evaluation in Lung Cancer) clinical trial evaluated the efficacy of gefitinib versus placebo in pretreated nonsmall-cell lung cancer patients. Two different antibodies, scoring systems, and cutoff points of epidermal growth factor receptor (EGFR) protein expression were compared to predict response and survival of enrolled patients. METHODS EGFR expression was assessed in tumor samples by immunohistochemistry using the Dako EGFR pharmDx kit (scoring percent of tumor cells with positive staining) and Zymed monoclonal antibody clone 31G7 (scoring staining index derived from proportion of positive cells times staining intensity). RESULTS Data for EGFR expression were available for 379 patients for Dako and 357 patients for Zymed antibody (22% and 21%, respectively, of trial population). Objective response rates in gefitinib-treated EGFR-positive patients defined with various cutpoints with Dako antibody varied between 8% and 12%, and with Zymed antibody between 10% and 13%. Lower cutoff points with Dako antibody provided the best discrimination between EGFR-positive and EGFR-negative patients for survival hazard ratios comparing gefitinib to placebo, with a significant treatment/cutoff point interaction for 10% cutoff point (P = .049). A similar but less apparent trend was noted for Zymed antibody, although the discrimination between hazard ratios was not significant for any cutoff point analyzed. CONCLUSIONS Assessment with the Dako PharmDx kit and percentage of cells with positive staining may provide more accurate prediction of differential effect on survival with gefitinib than assessment with Zymed antibody and staining index. Using higher cutpoints to define positivity does not improve test discrimination. PMID:18219661

  18. Characterization of growth factors in human cartilage.

    PubMed

    Bekoff, M C; Klagsbrun, M

    1982-01-01

    Growth factor activity has been identified in the chondrocytes and extracellular matrix (ECM) fractions of human costal cartilage. There was about five times more growth factor activity in the ECM than was found to be associated with the chondrocytes. The growth factor activity in chondrocytes was found to be associated with chromatin. Both the chromatin-associated growth factor (CAGF) activity and extracellular matrix growth factor (EMGF) activity were characterized for molecular weight, charge, and the effect of reduction by sulfhydryl reducing reagents. Biorex cation exchange chromatography showed that both CAGF and EMGF were cationic. CAGF and EMGF have molecular weights between 15,000 and 18,000 as determined by size exclusion chromatography on HPLC TSK 3000 columns equilibrated with guanidine-HCl and dithiothreitol. PMID:7169497

  19. Efficacy of palifermin (keratinocyte growth factor-1) in the amelioration of oral mucositis

    PubMed Central

    Sonis, Stephen T

    2010-01-01

    Purpose: Oral mucositis is a significant toxicity of cytotoxic chemo- and radiation-therapy used to treat cancer. Palifermin is the first pharmaceutical/biological agent approved for the intervention of oral mucositis. The major objective of this review is to evaluate the evidence supporting the use of palifermin. Methods: A literature search was performed using an appropriate keyword search in MEDLINE and PubMed databases. Results: Of 100 full papers and 4 abstracts identified, 12 papers and 3 abstracts were appropriate for analysis. Level 2 evidence supporting palifermin use in patients with hematologic malignancies being treated with autologous hematopoietic stem cell transplantation (HSCT) is clear. Level 2 evidence also exists for the use of palifermin in the prevention of oral mucositis in patients with solid tumors (colorectal cancer, head and neck cancer), but is incomplete. Level ? 3 data support the use of palifermin in allogeneic HSCT recipients and cycled chemotherapy. A single health economic study concluded that palifermin is essentially cost neutral in the autologous HSCT population. Conclusion: Data supporting the use of palifermin in autologous HSCT recipients with hematologic malignancies is clear. Some data exist demonstrating its efficacy in other oncologic indications. Additional studies are needed to broaden the potential applications of palifermin and to ascertain its economic, but not symptomatic, effectiveness. PMID:20694076

  20. Keratinocyte growth factor signalling: a mathematical model of dermalepidermal interaction in epidermal wound healing

    E-print Network

    Rohani, Pejman

    healing; Dermal±epidermal interaction; Travelling waves 1. Introduction Injury in mammalian skin initiates damaged, epidermal cell migration and proliferation occur in parallel with wound contraction and matrix mechanism is thought to best describe what occurs in mammalian skin, although ®rm evidence is lacking. Soon

  1. Growth Factors for the Treatment of Ischemic Brain Injury (Growth Factor Treatment)

    PubMed Central

    Larpthaveesarp, Amara; Ferriero, Donna M.; Gonzalez, Fernando F.

    2015-01-01

    In recent years, growth factor therapy has emerged as a potential treatment for ischemic brain injury. The efficacy of therapies that either directly introduce or stimulate local production of growth factors and their receptors in damaged brain tissue has been tested in a multitude of models for different Central Nervous System (CNS) diseases. These growth factors include erythropoietin (EPO), vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor (BDNF), and insulin-like growth factor (IGF-1), among others. Despite the promise shown in animal models, the particular growth factors that should be used to maximize both brain protection and repair, and the therapeutic critical period, are not well defined. We will review current pre-clinical and clinical evidence for growth factor therapies in treating different causes of brain injury, as well as issues to be addressed prior to application in humans. PMID:25942688

  2. Growth factors from genes to clinical application

    SciTech Connect

    Sara, V.R. (Dept. of Pathology, Karolinska Hospital, Stockholm (SE)); Hall, K.; Low, H. (Dept. of Endocrinology, Karolinska Hospital, Stockholm (SE))

    1990-01-01

    The last decade has witnessed an explosion in the identification of growth factors and their receptors. This has been greatly facilitated by recombinant DNA technology, which has provided the tools not only to identify these proteins at the gene level but also to produce recombinant proteins for evaluating their biological activities. With the help of such techniques, we are moving toward an understanding of the biosynthesis of growth factors and their receptors, structure-function relationships, as well as mechanisms for intracellular signal transmission. The possibility of modifying these factors has opened new fields of clinical application. In this paper, four major areas of growth factor research are presented: the characterization of growth factor genes and their protein products, growth factor receptors and signal transduction by the receptors to mediate biological action, the biological actions of the various growth factors, and the role of growth factors in health and disease and their possible clinical application. Some of the topics covered include: structure of the IGFs and their variants; isoforms of PDGF receptor types; tyrosine kinase activation; structure of G-proteins in biological membranes; possible therapeutic application of NGF in the treatment of Parkinson's and Alzheimer's diseases; PDGF's possible role in the development of several fibroproliferative diseases and its therapeutic application in wound healing; and the possible use of angiogenic inhibitors in tumor treatment.

  3. Expression of transforming growth factor-? and epidermal growth factor receptor in gastrointestinal stromal tumours

    Microsoft Academic Search

    Yun-Cai Cai; Zhong Jiang; Frank Vittimberga; Xiaowen Xu; Lou Savas; Bruce Woda; Mark Callery; Barbara Banner

    1999-01-01

    Activation of epidermal growth factor receptor (EGFR) is associated with cell growth and transformation. Both transforming\\u000a growth factor-? (TGF-?) and epidermal growth factor bind to and activate EGFR. We studied the expression of TGF-? and two\\u000a EGFRs (HER-1 and HER-2) in gastrointestinal stromal tumours (GISTs) of the stomach (n=9) and small intestine (n=6) using standard immunostaining techniques in paraffin-embedded sections.

  4. P2Y2 receptor inhibits EGF-induced MAPK pathway to stabilise keratinocyte hemidesmosomes.

    PubMed

    Faure, Emilie; Garrouste, Françoise; Parat, Fabrice; Monferran, Sylvie; Leloup, Ludovic; Pommier, Gilbert; Kovacic, Hervé; Lehmann, Maxime

    2012-09-15

    ?6?4 integrin is the main component of hemidesmosomes (HD) that stably anchor the epithelium to the underlying basement membrane. Epithelial cell migration requires HD remodelling, which can be promoted by epidermal growth factor (EGF). We previously showed that extracellular nucleotides inhibit growth factor-induced keratinocyte migration. Here, we investigate the effect of extracellular nucleotides on ?6?4 integrin localisation in HD during EGF-induced cell migration. Using a combination of pharmacological inhibition and gene silencing approaches, we found that UTP activates the P2Y2 purinergic receptor and G?q protein to inhibit EGF/ERK1/2-induced cell migration in keratinocytes. Using a keratinocyte cell line expressing an inducible form of the Raf kinase, we show that UTP inhibits the EGF-induced ERK1/2 pathway activation downstream of Raf. Moreover, we established that ERK1/2 activation by EGF leads to the mobilisation of ?6?4 integrin from HD. Importantly, activation of P2Y2R and G?q by UTP promotes HD formation and protects these structures from EGF-triggered dissolution as revealed by confocal analysis of the distribution of ?6?4 integrin, plectin, BPAG1, BPAG2 and CD151 in keratinocytes. Finally, we demonstrated that the activation of p90RSK, downstream of ERK1/2, is sufficient to promote EGF-mediated HD dismantling and that UTP does not stabilise HD in cells expressing an activated form of p90RSK. Our data underline an unexpected role of P2Y2R and G?q in the inhibition of the ERK1/2 signalling pathway and in the modulation of hemidesmosome dynamics and keratinocyte migration. PMID:22718344

  5. PAI-1 Mediates the TGF-?1+EGF-Induced “Scatter” Response in Transformed Human Keratinocytes

    PubMed Central

    Freytag, Jennifer; Wilkins-Port, Cynthia E.; Higgins, Craig E.; Higgins, Stephen P.; Samarakoon, Rohan; Higgins, Paul J.

    2013-01-01

    Cooperative interactions between growth factor signaling pathways are important elements in carcinoma progression. A model system combining transforming growth factor-?1 (TGF-?1) and EGF was developed to investigate mechanisms underlying induced epithelial-to-mesenchymal transition (EMT) in ras-transformed human (HaCaT II-4) keratinocytes. Dual stimulation with TGF-?1+EGF resulted in keratinocyte “plasticity” and pronounced colony dispersal. The most highly expressed transcript, identified by mRNA profiling, encoded plasminogen activator inhibitor-1 (PAI-1; SERPINE1). PAI-1 negatively regulates plasmin-dependent matrix degradation, preserving a stromal scaffold permissive for keratinocyte motility. Mitogen-activated extracellular kinase (MEK)/extracellular signal-regulated kinase (ERK) and p38 signaling were required for maximal PAI-1 upregulation and TGF-?1+EGF-stimulated cell locomotion, as pharmacologic disruption of MEK/p38 activity ablated both responses. Moreover, PAI-1 knockdown alone effectively inhibited TGF-?1+EGF-dependent cell scattering, indicating a functional role for this SERPIN in the dual-growth factor model of induced motility. Moreover, EGFR signaling blockade or EGFR knockdown attenuated TGF-?1-induced PAI-1 expression, implicating EGFR transactivation in TGF-?1-stimulated PAI-1 expression, and reduced colony dispersal in TGF-?1+EGF-treated cultures. Identification of such cooperative signaling networks and their effect on specific invasion-promoting target genes, such as PAI-1, may lead to the development of pathway-specific therapeutics that affect late-stage events in human tumor progression. PMID:20428185

  6. Growth factor involvement in tension-induced skeletal muscle growth

    NASA Technical Reports Server (NTRS)

    Vandenburgh, H. H.

    1987-01-01

    Muscle tissue culture techniques were developed to grow skeletal myofibers which differentiate into more adult-like myofibers. Mechanical simulation studies of these muscle cells in a newly developed mechanical cell simulator can now be performed to study growth processes in skeletal muscle. Conditions in the mechanical cell simulator were defined where mechanical activity can either prevent muscle wasting or stimulate muscle growth. The role of endogenous and exogenous growth factors in tension-induced muscle growth is being investigated under the defined conditions of tissue culture.

  7. Factor-binding element in the human c-myc promoter involved in transcriptional regulation by transforming growth factor. beta. 1 and by the retinoblastoma gene product

    SciTech Connect

    Pietenpol, J.A.; Stein, R.W.; Moses, H.L. (Vanderbilt Univ., Nashville, TN (United States)); Muenger, K.; Howley, P.M. (National Cancer Inst., Bethesda, MD (United States))

    1991-11-15

    Previous studies have shown that transforming growth factor {beta}1 (TGF-{beta}1) inhibition of keratinocyte proliferation involves suppression of c-myc transcription, and indirect evidence has suggested that the retinoblastoma gene product (pRB) may be involved in this process. In this study, transient expression of pRB in skin keratinocytes was shown to repress transcription of the human c-myc promoter region was required for regulation by both TGF-{beta}1 and pRB. These sequences, termed the TGF-{beta} control element (TCE), lie between positions {minus}86 and {minus}63 relative to the P1 transcription start site. Oligonucleotides containing the TCE bound to several nuclear factors in mobility-shift assays using extracts from cells with or without normal pRB. Binding of some factors was inhibited by TGF-{beta}1 treatment of TGF-{beta}-sensitive but not TGF-{beta}-insensitive cells. These data indicate that pRB can suppress c-myc transcription and growth inhibition.

  8. Cancer cells. 3: Growth factors and transformation

    SciTech Connect

    Feramisco, J.; Ozanne, B.; Stiles, C.

    1985-01-01

    This book contains over 50 papers. Some of the titles are: Structure of Human Epidermal Growth Factor and Expression of Normal and Variant mRNAs in Epdermoid Carcinoma Cells; Tyrosine Kinase Activity Associated with the v-erb-B Gene Product; Cloning and Characterization of Human Epidermal Growth Factor-Receptor Gene Sequences in A431 Carcinoma Cells; Anti-oncogenes and the Suppression of Tumor Formation; and Normal Human sis/PDGF-2 Gene Expression Induces Cellular Transformation.

  9. Growth Factors and Neuropathic Pain

    Microsoft Academic Search

    Michael H. Ossipov

    2011-01-01

    A treatment for neuropathic pain is an important unmet medical need because this pain often is refractory to many medical\\u000a interventions. An important element in the development of neuropathic pain is a dysfunction in the activity of peripheral\\u000a nerves. Because neurotrophic factors affect nerve development and maintenance, modulating the activity of these factors can\\u000a alter neuronal pathophysiology and produce a

  10. Vascular growth factors in neuropsychiatry

    PubMed Central

    Newton, Samuel S.; Fournier, Neil M.; Duman, Ronald S.

    2014-01-01

    Recent advances in understanding the cellular and molecular basis of psychiatric illnesses have shed light on the important role played by trophic factors in modulating functional parameters associated with disease causality and drug action. Disease mechanisms are now thought to involve multiple cell types, including neurons and endothelial cells. These functionally distinct but interactively coupled cell types engage in cellular cross talk via shared and common signaling molecules. Dysregulation in their cellular signaling pathways influences brain function and alters behavioral performance. Multifunctional trophic factors such as VEGF and EPO that possess both neurotrophic and angiogenic actions are of particular interest due to their ability to rescue structural and plasticity deficits in neurons and vasculature. Obtaining insight into the behavioral, cellular and molecular actions of multi-functional trophic factors has the potential to open new and transformative therapeutic approaches. PMID:23475069

  11. Biphasic Regulation of HMG-CoA Reductase Expression and Activity during Wound Healing and Its Functional Role in the Control of Keratinocyte Angiogenic and Proliferative Responses*

    PubMed Central

    Schiefelbein, Dana; Goren, Itamar; Fisslthaler, Beate; Schmidt, Helmut; Geisslinger, Gerd; Pfeilschifter, Josef; Frank, Stefan

    2008-01-01

    In this study, we determined the regulation and potential function of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase (HMGR) during skin repair in mice. Upon skin injury, healthy mice exhibited a biphasic increase in HMGR expression and activity with elevated levels at days 3 and 13 post-wounding. In situ hybridization revealed wound margin keratinocytes as a cellular source of HMGR expression. In vitro experiments using cultured HaCaT keratinocytes uncovered epidermal growth factor (EGF), transforming growth factor (TGF)-?, and insulin as potent co-inducers of HMGR activity and vascular endothelial growth factor (VEGF) in the cells. Insulin-, but not EGF-mediated VEGF protein expression was functionally connected to co-induced HMGR activity, as simvastatin restrictively interfered only with insulin-induced translation of VEGF mRNA by inhibition of eukaryotic initiation factor 4E-binding protein 1 (4E-BP1) phosphorylation. Functional ablation of insulin-induced sterol regulatory element-binding protein (SREBP)-2 by siRNA abolished HMGR expression and insulin-triggered VEGF protein release from keratinocytes. Simvastatin also blocked proliferation of cultured keratinocytes. The observed inhibitory effects of simvastatin on keratinocyte VEGF expression and proliferation could be reversed by mevalonate, the product of HMGR enzymatic activity. In accordance, simvastatin-mediated inhibition of HMGR activity in acutely regenerating tissue of wounded mice was paralleled by a marked loss of VEGF protein expression and disturbances of normal proliferation processes in wound margin keratinocytes during skin repair. PMID:18390541

  12. Vascular endothelial growth factor (VEGF) in endometriosis

    Microsoft Academic Search

    Jacques Donnez; Pierre Smoes; Stephane Gillerot; Francoise Casanas-Roux; Michelle Nisolle

    1998-01-01

    Angiogenesis is likely to be involved in the pathogenesis of endometriosis. According to the transplantation theory, when the exfoliated endometrium is attached to the periton- eal layer, the establishment of a new blood supply is essential for the survival of the endometrial implant and development of endometriosis. From the known angiogenic factors, vascular endothelial growth factor (VEGF) has emerged as

  13. Murine Oligodendroglial Cells Express Nerve Growth Factor

    Microsoft Academic Search

    Sujatha Byravan; Lyndon M. Foster; Tommy Phan; A. Neil Verity; Anthony T. Campagnoni

    1994-01-01

    The studies reported here present evidence for the expression of nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) by an oligodendroglial cell line and of NGF by oligodendrocytes in mouse primary culture. An immortalized oligodendroglial cell line (N19) expressing markers for immature oligodendrocytes stimulated PC12 cells to elaborate processes. Polymerase chain reaction analysis with degenerate primers indicated that the

  14. EGFR-driven up-regulation of decoy receptor 3 in keratinocytes contributes to the pathogenesis of psoriasis.

    PubMed

    Wu, Nan-Lin; Huang, Duen-Yi; Hsieh, Shie-Liang; Hsiao, Cheng-Hsiang; Lee, Te-An; Lin, Wan-Wan

    2013-10-01

    Decoy receptor 3 (DcR3) is a soluble receptor of Fas ligand (FasL), LIGHT (TNFSF14) and TNF-like molecule 1A (TL1A) and plays pleiotropic roles in many inflammatory and autoimmune disorders and malignant diseases. In cutaneous biology, DcR3 is expressed in primary human epidermal keratinocytes and is upregulated in skin lesions in psoriasis, which is characterized by chronic inflammation and angiogenesis. However, the regulatory mechanisms of DcR3 over-expression in skin lesions of psoriasis are unknown. Here, we demonstrate that DcR3 can be detected in both dermal blood vessels and epidermal layers of psoriatic skin lesions. Analysis of serum samples showed that DcR3 was elevated, but FasL was downregulated in psoriatic patients compared with normal individuals. Additional cell studies revealed a central role of epidermal growth factor receptor (EGFR) in controlling the basal expression of DcR3 in keratinocytes. Activation of EGFR by epidermal growth factor (EGF) and transforming growth factor (TGF)-? strikingly upregulated DcR3 production. TNF-??enhanced DcR3 expression in both keratinocytes and endothelial cells compared with various inflammatory cytokines involved in psoriasis. Additionally, TNF-?-enhanced DcR3 expression in keratinocytes was inhibited when EGFR was knocked down or EGFR inhibitor was used. The NF-?B pathway was critically involved in the molecular mechanisms underlying the action of EGFR and inflammatory cytokines. Collectively, the novel regulatory mechanisms of DcR3 expression in psoriasis, particularly in keratinocytes and endothelial cells, provides new insight into the pathogenesis of psoriasis and may also contribute to the understanding of other diseases that involve DcR3 overexpression. PMID:23707413

  15. Sgk3 links growth factor signaling to maintenance of progenitor cells in the hair follicle.

    PubMed

    Alonso, Laura; Okada, Hitoshi; Pasolli, Hilda Amalia; Wakeham, Andrew; You-Ten, Annick Itie; Mak, Tak W; Fuchs, Elaine

    2005-08-15

    Tyrosine kinase growth factor receptor signaling influences proliferation, survival, and apoptosis. Hair follicles undergo cycles of proliferation and apoptotic regression, offering an excellent paradigm to study how this transition is governed. Several factors are known to affect the hair cycle, but it remains a mystery whether Akt kinases that are downstream of growth factor signaling impact this equilibrium. We now show that an Akt relative, Sgk (serum and glucocorticoid responsive kinase) 3, plays a critical role in this process. Hair follicles of mice lacking Sgk3 fail to mature normally. Proliferation is reduced, apoptosis is increased, and follicles prematurely regress. Maintenance of the pool of transiently amplifying matrix cells is impaired. Intriguingly, loss of Sgk3 resembles the gain of function of epidermal growth factor signaling. Using cultured primary keratinocytes, we find that Sgk3 functions by negatively regulating phosphatidylinositol 3 kinase signaling. Our results reveal a novel and important function for Sgk3 in controlling life and death in the hair follicle. PMID:16103225

  16. Fracture induces keratinocyte activation, proliferation, and expression of pro-nociceptive inflammatory mediators.

    PubMed

    Li, Wen-Wu; Guo, Tian-Zhi; Li, Xiang-qi; Kingery, Wade S; Clark, J David

    2010-12-01

    Tibia fracture in rats results in chronic vascular and nociceptive changes in the injured limb resembling complex regional pain syndrome (CRPS) and up-regulates expression of interleukin 1? (IL-1?), interleukin IL-6 (IL-6), tumor necrosis factor-? (TNF-?), and nerve growth factor-? (NGF-?) in the hindpaw skin. When fractured rats are treated with cytokine or NGF inhibitors nociceptive sensitization is blocked. Because there is no leukocyte infiltration in the hindpaw skin we postulated that resident skin cells produce the inflammatory mediators causing nociceptive sensitization after fracture. To test this hypothesis rats underwent distal tibia fracture and hindlimb casting for 4 weeks, then the hindpaw skin was harvested and immunostained for keratin, cytokines and NGF. BrdU staining was used to evaluate cell proliferation. Hindpaw nociceptive thresholds, edema, and temperature were tested before and up to 96h after intraplantar injections of IL-6 and TNF-?. Tibia fracture caused keratinocyte activation, proliferation, and up-regulated IL-1?, IL-6, TNF-? and NGF-? protein expression in the hindpaw keratinocytes. Local injections of IL-6 and TNF-? induced hindpaw mechanical allodynia lasting for several days and modest increases in temperature and edema. These data indicate that activated keratinocytes proliferate and express IL-1?, IL-6, TNF-?, and NGF-? after fracture and that excess amounts of inflammatory mediators in the skin cause sustained nociceptive sensitization. This is the first study demonstrating in vivo keratinocyte expression of IL-6, TNF-? and NGF-? in a CRPS model and we postulate that the keratinocyte is the primary cellular source for the inflammatory signals mediating cutaneous nociceptive sensitization in early CRPS. PMID:20934254

  17. EFFECT OF ARSENICALS ON ULTRAVIOLET-RADIATION-INDUCED GROWTH ARREST AND RELATED SIGNALING EVENTS IN HUMAN KERATINOCYTES

    EPA Science Inventory

    The molecular mechanisms mediating arsenic-induced carcinogenesis are not well understood. The role of confounding factors such as ultraviolet radiation (UV), add another level of complexity to the study of arsenic carcinogenesis and the cancer risk assessment to humans. We hypot...

  18. Transforming growth factor-? regulates production of proteoglycans by mesangial cells

    Microsoft Academic Search

    Wayne A Border; Seiya Okuda; Lucia R Languino; Erkki Ruoslahti

    1990-01-01

    Transforming growth factor-? regulates production of proteoglycans by mesangial cells. Accumulation of glomerular extracellular matrix is a prominent feature of most forms of progressive glomerular disease. Since some growth factors may play a role in extracellular matrix production, we examined the effects of transforming growth factor-? (TGF-?), interleukin 1, platelet derived growth factor, and tumor necrosis factor on the production

  19. Placenta Growth Factor in Diabetic Wound Healing

    PubMed Central

    Cianfarani, Francesca; Zambruno, Giovanna; Brogelli, Laura; Sera, Francesco; Lacal, Pedro Miguel; Pesce, Maurizio; Capogrossi, Maurizio C.; Failla, Cristina Maria; Napolitano, Monica; Odorisio, Teresa

    2006-01-01

    Reduced microcirculation and diminished expression of growth factors contribute to wound healing impairment in diabetes. Placenta growth factor (PlGF), an angiogenic mediator promoting pathophysiological neovascularization, is expressed during cutaneous wound healing and improves wound closure by enhancing angiogenesis. By using streptozotocin-induced diabetic mice, we here demonstrate that PlGF induction is strongly reduced in diabetic wounds. Diabetic transgenic mice overexpressing PlGF in the skin displayed accelerated wound closure compared with diabetic wild-type littermates. Moreover, diabetic wound treatment with an adenovirus vector expressing the human PlGF gene (AdCMV.PlGF) significantly accelerated the healing process compared with wounds treated with a control vector. The analysis of treated wounds showed that PlGF gene transfer improved granulation tissue formation, maturation, and vascularization, as well as monocytes/macrophages local recruitment. Platelet-derived growth factor, fibroblast growth factor-2, and vascular endothelial growth factor mRNA levels were increased in AdCMV.PlGF-treated wounds, possibly enhancing PlGF-mediated effects. Finally, PlGF treatment stimulated cultured dermal fibroblast migration, pointing to a direct role of PlGF in accelerating granulation tissue maturation. In conclusion, our data indicate that reduced PlGF expression contributes to impaired wound healing in diabetes and that PlGF gene transfer to diabetic wounds exerts therapeutic activity by promoting different aspects of the repair process. PMID:17003476

  20. Growth factor delivery approaches in hydrogels.

    PubMed

    Silva, Amanda K Andriola; Richard, Cyrille; Bessodes, Michel; Scherman, Daniel; Merten, Otto-Wilhelm

    2009-01-12

    The controlled delivery of growth factors is a very challenging task because many different issues have to be addressed to develop the best suited system. A wide range of approaches have been employed for the controlled delivery of growth factors by hydrogels. Direct loading, electrostatic interaction, covalent binding, and the use of carriers are the main strategies presented in the literature. They are all detailed in the first part of this review. Recent work emphasizing biologically inspired strategies is also included. Also, both natural and synthetic materials are discussed. The second part comprises the methods to evaluate such delivery approaches. Both in vivo and in vitro techniques are presented. Improvements based on the discussed approaches may illustrate future paths toward the development of an ideal growth factor delivery system. PMID:19032110

  1. Organotypic Modeling of Human Keratinocyte Response 1 to Peroxisome Proliferators

    PubMed Central

    Zhang, Carmen; Gurevich, Igor; Aneskievich, Brian J.

    2013-01-01

    Peroxisome proliferators (PPs) are a diverse chemical group including hypolipidemic drugs and some fatty acids. Their stimulation of PP activated receptors (PPAR) and subsequent control of gene expression regulates metabolism and differentiation in many cells. PPs have multiple opportunities to target human epidermal keratinocytes because of delivery through dietary, clinical and/or topical exposure routes. PPAR knockout mice and PP treatment of mouse skin or human keratinocytes in monolayer culture have established some effects for PPs in cutaneous differentiation. However, incomplete epidermal maturation characteristic of monolayer keratinocytes and rodent-specific effects may limit our full understanding of human keratinocyte responses to PPs. To address these issues, we investigated PP influence on primary human keratinocytes in organotypic cultures that recapitulate biochemical markers of epidermis. We found the PPAR? agonists clofibrate, docasohexaenoic acid, and WY-14,643 produced mild to moderate keratinocyte hyperplasia, increased stratification, particularly of granular and cornified layers, and enhanced levels of the differentiation markers filaggrin, ABCA12, and phosphorylated HSP27. Several PP effects generated in the organotypic system however were distinct from those previously reported for rodent skin and human keratinocyte monolayer cultures suggesting the species and growth context of target cells can impact exposure outcomes. Given the utility of organotypic cultures to modeling the epidermis, studies in this system may bridge the gap between the rodent assays and clinical studies of human epidermal responses to PPs. PMID:22677707

  2. Growth factor parametrization in curved space

    SciTech Connect

    Gong Yungui; Ishak, Mustapha; Wang Anzhong [College of Mathematics and Physics, Chongqing University of Posts and Telecommunications, Chongqing 400065 (China) and Kavli Institute for Theoretical Physics China, CAS, Beijing 100190 (China); Department of Physics, University of Texas at Dallas, Richardson, Texas 75083 (United States); CASPER, Physics Department, Baylor University, Waco, Texas 76798 (United States)

    2009-07-15

    The growth rate of matter perturbation and the expansion rate of the Universe can be used to distinguish modified gravity and dark energy models in explaining cosmic acceleration. We explore here the inclusion of spatial curvature into the growth factor. We expand previous results using the approximation {omega}{sub m}{sup {gamma}} and then suggest a new form, f{sub a}={omega}{sub m}{sup {gamma}}+({gamma}-4/7){omega}{sub k}, as an approximation for the growth factor when the curvature {omega}{sub k} is not negligible, and where the growth index {gamma} is usually model dependent. The expression recovers the standard results for the curved and flat {lambda}CDM and Dvali-Gabadadze-Porrati models. Using the best fit values of {omega}{sub m0} and {omega}{sub k0} to the expansion/distance measurements from Type Ia SNe, baryon acoustic oscillation, WMAP5, and H(z) data, we fit the growth index parameter to current growth factor data and obtain {gamma}{sub {lambda}}({omega}{sub k}{ne}0)=0.65{sub -0.15}{sup +0.17} and {gamma}{sub DGP}({omega}{sub k}{ne}0)=0.53{sub -0.12}{sup +0.14}. For the {lambda}CDM model, the 1-{sigma} observational bounds are found consistent with theoretical value, unlike the case for the Dvali-Gabadadze-Porrati model. We also find that the current data we used is not enough to put significant constraints when the 3 parameters in f{sub a} are fit simultaneously. Importantly, we find that, in the presence of curvature, the analytical expression proposed for f{sub a} provides a better fit to the growth factor than other forms and should be useful for future high precision missions and studies.

  3. Differentiated Keratinocyte-Releasable Stratifin (14-3-3 Sigma) Stimulates MMP-1 Expression in Dermal Fibroblasts

    Microsoft Academic Search

    Aziz Ghahary; Yvonne Marcoux; Feridoun Karimi-Busheri; Yunyaun Li; Edward E. Tredget; Ruhangiz T. Kilani; Eugene Lam; Michael Weinfeld

    2005-01-01

    Through the use of a keratinocyte\\/fibroblast co-culture system, we have recently identified a potent keratinocyte-derived anti-fibrogenic factor (KDAF) for dermal fibroblasts. A sequential chromatography of the active fractions of keratinocyte-conditioned medium (KCM) and peptide mapping of the candidate proteins identified KDAF as being the keratinocyte-releasable 14-3-3 sigma (14-3-3?) protein, which is also known as stratifin. In this study, we hypothesize

  4. Growth factors in lung development and disease: friends or foe?

    Microsoft Academic Search

    Tushar J Desai; Wellington V Cardoso

    2002-01-01

    Growth factors mediate tissue interactions and regulate a variety of cellular functions that are critical for normal lung development and homeostasis. Besides their involvement in lung pattern formation, growth and cell differentiation during organogenesis, these factors have been also implicated in modulating injury-repair responses of the adult lung. Altered expression of growth factors, such as transforming growth factor ?1, vascular

  5. Platelet-derived growth factors and fibroblast growth factors are mitogens for rat Schwann cells

    Microsoft Academic Search

    John B. Davis; Paul Stroobant

    1990-01-01

    Rat sciatic nerve Schwann cells in culture respond to a limited range of mitogens, including glial growth factor, transforming growth factors beta-1 and beta-2 (TGF-fll, TGF-\\/~2), some cell mem- brane-associated factors, and to agents such as cholera toxin and forskolin which raise intracellular levels of cAME These responses require the presence of FCS, which exhibits little or no mitogenic activity

  6. Targeting the epidermal growth factor receptor

    Microsoft Academic Search

    B F El-Rayes; P M LoRusso

    2004-01-01

    The epidermal growth factor receptor (EGFR) is a member of the erbB family of tyrosine kinase receptors (RTK). The EGFR is involved in cell proliferation, metastasis and angiogenesis, and is expressed in a large proportion of epithelial tumours. The two main classes of EGFR inhibitors in clinical trials are the RTK inhibitors and the monoclonal antibodies. The clinical development of

  7. Cellular Signalling: Peptide Hormones and Growth Factors

    Microsoft Academic Search

    Barry I. Posner; Stephane A. Laporte

    2010-01-01

    Peptide hormones and growth factors initiate signalling by binding to and activating their cell surface receptors. The activated receptors interact with and modulate the activity of cell surface enzymes and adaptor proteins which entrain a series of reactions leading to metabolic and proliferative signals. Rapid internalization of ligand–receptor complexes into the endosomal system both prolongs and augments events initiated at

  8. PCB153 reduces telomerase activity and telomere length in immortalized human skin keratinocytes (HaCaT) but not in human foreskin keratinocytes (NFK)

    SciTech Connect

    Senthilkumar, P.K. [Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA (United States)] [Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA (United States); Robertson, L.W. [Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA (United States) [Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA (United States); Department of Occupational and Environmental Health, The University of Iowa, Iowa City, IA (United States); Ludewig, G., E-mail: Gabriele-ludewig@uiowa.edu [Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA (United States); Department of Occupational and Environmental Health, The University of Iowa, Iowa City, IA (United States)

    2012-02-15

    Polychlorinated biphenyls (PCBs), ubiquitous environmental pollutants, are characterized by long term-persistence in the environment, bioaccumulation, and biomagnification in the food chain. Exposure to PCBs may cause various diseases, affecting many cellular processes. Deregulation of the telomerase and the telomere complex leads to several biological disorders. We investigated the hypothesis that PCB153 modulates telomerase activity, telomeres and reactive oxygen species resulting in the deregulation of cell growth. Exponentially growing immortal human skin keratinocytes (HaCaT) and normal human foreskin keratinocytes (NFK) were incubated with PCB153 for 48 and 24 days, respectively, and telomerase activity, telomere length, superoxide level, cell growth, and cell cycle distribution were determined. In HaCaT cells exposure to PCB153 significantly reduced telomerase activity, telomere length, cell growth and increased intracellular superoxide levels from day 6 to day 48, suggesting that superoxide may be one of the factors regulating telomerase activity, telomere length and cell growth compared to untreated control cells. Results with NFK cells showed no shortening of telomere length but reduced cell growth and increased superoxide levels in PCB153-treated cells compared to untreated controls. As expected, basal levels of telomerase activity were almost undetectable, which made a quantitative comparison of treated and control groups impossible. The significant down regulation of telomerase activity and reduction of telomere length by PCB153 in HaCaT cells suggest that any cell type with significant telomerase activity, like stem cells, may be at risk of premature telomere shortening with potential adverse health effects for the affected organism. -- Highlights: ? Human immortal (HaCaT) and primary (NFK) keratinocytes were exposed to PCB153. ? PCB153 significantly reduced telomerase activity and telomere length in HaCaT. ? No effect on telomere length and telomerase activity was found in NFK. ? Increased intracellular superoxide levels and reduced cell growth was seen in both. ? PCB153 may damage telomerase expressing cells like stem cells.

  9. Activated keratinocytes in the epidermis of hypertrophic scars.

    PubMed Central

    Machesney, M.; Tidman, N.; Waseem, A.; Kirby, L.; Leigh, I.

    1998-01-01

    The etiology of hypertrophic scarring, a pathological end point of wound healing, is unknown. The scars most commonly occur when epithelialization has been delayed during, for example, the healing of deep dermal burn wounds. Hypertrophic scars are conventionally described as a dermal pathology in which the epidermis has only a passive role. In this study, the expression of keratin intermediate filament proteins and filaggrin has been investigated in the epidermis of hypertrophic scars and site-matched controls from the same patients. Hypertrophic scar epidermis was found to express the hyperproliferative keratins K6 and K16 in interfollicular epidermis in association with K17 and precocious expression of filaggrin. K16 mRNA was localized by in situ hybridization using a highly specific cRNA probe. In contrast to the immunohistochemical location of K16 protein, the K16 mRNA was found to be expressed in the basal cell layer of normal skin. In hypertrophic scars the mRNA distribution corroborated the abnormal K16 protein distribution. These results suggest the keratinocytes in hypertrophic scar epidermis have entered an alternative differentiation pathway and are expressing an activated phenotype. Activated keratinocytes are a feature of the early stages of wound healing producing growth factors that influence fibroblasts, endothelial cells, and the inflammatory response. We propose that cellular mechanisms in the pathogenesis of hypertrophic scarring are more complex than isolated dermal phenomena. The persistence of activated keratinocytes in hypertrophic scar epidermis implicates abnormal epidermal-mesenchymal interactions. Images Figure 1 Figure 3 PMID:9588880

  10. Transcriptional Profiling of Ectoderm Specification to Keratinocyte Fate in Human Embryonic Stem Cells

    PubMed Central

    Tadeu, Ana Mafalda Baptista; Lin, Samantha; Hou, Lin; Chung, Lisa; Zhong, Mei; Zhao, Hongyu; Horsley, Valerie

    2015-01-01

    In recent years, several studies have shed light into the processes that regulate epidermal specification and homeostasis. We previously showed that a broad-spectrum ?–secretase inhibitor DAPT promoted early keratinocyte specification in human embryonic stem cells triggered to undergo ectoderm specification. Here, we show that DAPT accelerates human embryonic stem cell differentiation and induces expression of the ectoderm protein AP2. Furthermore, we utilize RNA sequencing to identify several candidate regulators of ectoderm specification including those involved in epithelial and epidermal development in human embryonic stem cells. Genes associated with transcriptional regulation and growth factor activity are significantly enriched upon DAPT treatment during specification of human embryonic stem cells to the ectoderm lineage. The human ectoderm cell signature identified in this study contains several genes expressed in ectodermal and epithelial tissues. Importantly, these genes are also associated with skin disorders and ectodermal defects, providing a platform for understanding the biology of human epidermal keratinocyte development under diseased and homeostatic conditions. PMID:25849374

  11. Growth factors and antral follicular development in domestic ruminants

    Microsoft Academic Search

    D. Monniaux; P. Monget; N. Besnard; C. Huet; C. Pisselet

    1997-01-01

    Growth factors of endocrine and\\/or paracrine origin play determinant roles in antral follicular development. They modulate survival, proliferation and differentiation of follicular cells, acting in interaction with gonadotropins. It is thought that factors belonging to the families of the insulin-like growth factor (IGF-I and -II), epidermal growth factor (EGF and TGF-?) and fibroblast growth factor (FGF) can support growth of

  12. Reprogramming human adipose tissue stem cells using epidermal keratinocyte extracts

    PubMed Central

    XIE, FENG; TANG, XINJIE; ZHANG, QUN; DENG, CHENLIANG

    2015-01-01

    Human adipose tissue stem cells (ATSCs) can differentiate into various types of cell in response to lineage-specific induction factors. Reprogramming cells using nuclear and cytoplasmic extracts derived from another type of somatic cell is an effective method of producing specific types of differentiated cell. In the present study, the ability of reprogrammed ATSCs to acquire epidermal keratinocyte properties following transient exposure to epidermal keratinocyte extracts was demonstrated. Reversibly permeabilized ATSCs were incubated for 1 h in nuclear and cytoplasmic extracts from epidermal keratinocytes, resealed with CaCl2 and cultured. ATSC reprogramming is demonstrated by nuclear uptake of epidermal keratinocyte extracts. After one week of exposure to extracts, ATSCs underwent changes in cell morphology, cell-specific genes were activated, and epidermal keratinocyte markers including K19 and K1/K10 (markers of stem cells and terminally differentiated keratinocytes, respectively) were expressed. This study indicates that the reprogramming of ATSCs using nuclear and cytoplasmic extracts from epidermal keratinocytes is a viable option for the production of specific types of cell. PMID:25333210

  13. Altered (/sup 125/I)epidermal growth factor binding and receptor distribution in psoriasis

    SciTech Connect

    Nanney, L.B.; Stoscheck, C.M.; Magid, M.; King, L.E. Jr.

    1986-03-01

    Stimulation of growth and differentiation of human epidermis by epidermal growth factor (EGF) is mediated by its binding to specific receptors. Whether EGF receptors primarily mediate cell division or differentiation in hyperproliferative disease such as psoriasis vulgaris is unclear. To study the pathogenesis of psoriasis, 4-mm2 punch biopsy specimens of normal, uninvolved, and involved psoriatic skin were assayed for EGF receptors by autoradiographic, immunohistochemical, and biochemical methods. Using autoradiographic and immunohistochemical methods, basal keratinocytes were found to contain the greatest number of EGF binding sites and immunoreactive receptors as compared to the upper layers of the epidermis in both normal epidermis and psoriatic skin. No EGF receptor differences between normal and psoriatic epidermis were observed in this layer. In the upper layers of the epidermis, a 2-fold increase in EGF binding capacity was observed in psoriatic skin as compared with normal thin or thick skin. Biochemical methods indicated that (/sup 125/I)EGF binding was increased in psoriatic epidermis as compared with similar thickness normal epidermis when measured on a protein basis. Epidermal growth factor was shown to increase phosphorylation of the EGF receptor in skin. EGF receptors retained in the nonmitotic stratum spinosum and parakeratotic stratum corneum may reflect the incomplete, abnormal differentiation that occurs in active psoriatic lesions. Alternatively, retained EGF receptors may play a direct role in inhibiting cellular differentiation in the suprabasal layers.

  14. Insulin-like growth factor I during growth in bulls.

    PubMed

    Ronge, H; Blum, J

    1989-01-01

    In 10 bulls, changes in blood plasma concentrations of insulin-like growth factor I (IGF1) were studied during rearing and during the ensuing growth period. IGF1 continuously increased from 32 micrograms/l at the age of 15 d to 194 micrograms/l at the age of 307 d together with body weight. However, IGF1 was not related to daily rate of gain, which remained fairly constant during the growth period. An age-dependent increase was also observed for blood levels of insulin, thyroxine and triiodothyronine. The data suggest that insulin and thyroid hormones may be causally related to the age-dependent increase in IGF1 levels. PMID:2928598

  15. Nerve Growth Factor and Diabetic Neuropathy

    PubMed Central

    Vinik, Aaron

    2003-01-01

    Neuropathy is one of the most debilitating complications of both type 1 and type 2 diabetes, with estimates of prevalence between 50–90% depending on the means of detection. Diabetic neuropathies are heterogeneous and there is variable involvement of large myelinated fibers and small, thinly myelinated fibers. Many of the neuronal abnormalities in diabetes can be duplicated by experimental depletion of specific neurotrophic factors, their receptors or their binding proteins. In experimental models of diabetes there is a reduction in the availability of these growth factors, which may be a consequence of metabolic abnormalities, or may be independent of glycemic control. These neurotrophic factors are required for the maintenance of the neurons, the ability to resist apoptosis and regenerative capacity. The best studied of the neurotrophic factors is nerve growth factor (NGF) and the related members of the neurotrophin family of peptides. There is increasing evidence that there is a deficiency of NGF in diabetes, as well as the dependent neuropeptides substance P (SP) and calcitonin gene-related peptide (CGRP) that may also contribute to the clinical symptoms resulting from small fiber dysfunction. Similarly, NT3 appears to be important for large fiber and IGFs for autonomic neuropathy. Whether the observed growth factor deficiencies are due to decreased synthesis, or functional, e.g. an inability to bind to their receptor, and/or abnormalities in nerve transport and processing, remains to be established. Although early studies in humans on the role of neurotrophic factors as a therapy for diabetic neuropathy have been unsuccessful, newer agents and the possibilities uncovered by further studies should fuel clinical trials for several generations. It seems reasonable to anticipate that neurotrophic factor therapy, specifically targeted at different nerve fiber populations, might enter the therapeutic armamentarium. PMID:14668049

  16. Binding of epidermal growth factor and insulin-like growth factor I in human myometrium and leiomyomata

    SciTech Connect

    Tommola, P.; Pekonen, F.; Rutanen, E.M. (Minerva Institute for Medical Research, Kauniainen (Finland))

    1989-10-01

    Samples of uterine myometrium and leiomyoma from 11 women were analyzed for the presence of epidermal growth factor receptors and insulin-like growth factor I receptors. In addition, the content of soluble insulin-like growth factor binding protein (IGF-BP/PP12) was measured in the tissue cytosols. Cell membrane preparations of myoma tissue bound significantly more insulin-like growth factor I than did those of adjacent normal myometrium, whereas myoma tissue bound less epidermal growth factor than did the normal myometrium. The differences in both insulin-like growth factor I and epidermal growth factor binding were due to changes in receptor concentration rather than to alterations in receptor affinity. Neither myoma nor myometrial tissue contained detectable levels of insulin-like growth factor binding protein. The changes in epidermal growth factor and insulin-like growth factor I binding to the myometrium may play a role in the pathogenesis of uterine leiomyomata.

  17. Epidermal growth factor (EGF) receptor gene transcription

    SciTech Connect

    Kageyama, R.; Merlino, G.T.; Pastan, I.

    1988-05-05

    The authors have studied in vitro transcription of the human epidermal growth factor (EGF) receptor proto-oncogene using nuclear extracts of A431 human epidermoid carcinoma cells, which overproduce the EGF receptor. With the in vitro system we found that Sp1 and other trans-acting factors bound to the EGF receptor promoter regions and are required for maximal expression. Fractionation showed that a DEAE-Sepharose fraction (BA) contained a novel factor, which specifically stimulated EGF receptor transcription 5- to 10-fold. The molecular mass of the native form of the factor is about 270-kDa based on its migration on Sephacryl S-300. This factor may activate transcription of the proto-oncogene through a weak or indirect interaction with the DNA template.

  18. Effects of Hepatocyte Growth Factor, Transforming Growth Factor-?1 and Epidermal Growth Factor on Bovine Corneal Epithelial Cells under Epithelial–Keratocyte Interaction in Reconstruction Culture

    Microsoft Academic Search

    TOMOHISA NISHIMURA; SHUJI TODA; TAKUYA MITSUMOTO; SHINJI OONO; HAJIME SUGIHARA

    1998-01-01

    In the cornea, corneal epithelial cells are in close contact with keratocytes: the epithelial cells organize thickened lamellar structure on a layer of keratocytes embedded in extracellular matrix (ECM). Thus, growth factors are expected to critically regulate corneal component cells under epithelial–keratocyte interaction. The purpose of this study is to clarify effects of hepatocyte growth factor (HGF), transforming growth factor-?1

  19. Post-transcriptional Regulation of Keratinocyte Progenitor Cell Expansion, Differentiation and Hair Follicle Regression by miR-22

    PubMed Central

    Meng, Qingyong; Zhao, Yiqiang; Chen, Lei; Zhang, Hongquan; Xue, Lixiang; Zhang, Xiuqing; Lengner, Christopher; Yu, Zhengquan

    2015-01-01

    Hair follicles (HF) undergo precisely regulated recurrent cycles of growth, cessation, and rest. The transitions from anagen (growth), to catagen (regression), to telogen (rest) involve a physiological involution of the HF. This process is likely coordinated by a variety of mechanisms including apoptosis and loss of growth factor signaling. However, the precise molecular mechanisms underlying follicle involution after hair keratinocyte differentiation and hair shaft assembly remain poorly understood. Here we demonstrate that a highly conserved microRNA, miR-22 is markedly upregulated during catagen and peaks in telogen. Using gain- and loss-of-function approaches in vivo, we find that miR-22 overexpression leads to hair loss by promoting anagen-to-catagen transition of the HF, and that deletion of miR-22 delays entry to catagen and accelerates the transition from telogen to anagen. Ectopic activation of miR-22 results in hair loss due to the repression a hair keratinocyte differentiation program and keratinocyte progenitor expansion, as well as promotion of apoptosis. At the molecular level, we demonstrate that miR-22 directly represses numerous transcription factors upstream of phenotypic keratin genes, including Dlx3, Foxn1, and Hoxc13. We conclude that miR-22 is a critical post-transcriptional regulator of the hair cycle and may represent a novel target for therapeutic modulation of hair growth. PMID:26020521

  20. Basic fibroblast growth factor: an autocrine growth factor for epiphyseal growth plate chondrocytes.

    PubMed

    Luan, Y; Praul, C A; Gay, C V; Leach, R M

    1996-09-01

    Basic fibroblast growth factor (bFGF) is a permissive mitogen for cultured chondrocytes and has been localized in the specific zones of the epiphyseal growth plate. In this study, we demonstrate that bFGF present in cartilage originates from within the cellular constituents of this tissue. Utilizing reverse transcription coupled to the polymerase chain reaction (PCR), bFGF mRNA was found in extracts of cartilage tissue. Immunocytochemical studies revealed that bFGF was present intracellularly in freshly isolated proliferative chondrocytes and in the extracellular matrix (ECM) after 24 h of culture. Western blot analysis of protein extracts from isolated proliferative chondrocytes identified a bFGF immunoreactive species with a molecular weight of approximately 18 kDa. In situ hybridization confirmed the presence of bFGF mRNA in freshly isolated proliferative chondrocytes. The bFGF in the ECM seemed to be sequestered and not available for biological activity, since these cells still required exogenous bFGF for cell proliferation. This sequestered bFGF could be released to stimulate cell proliferation when cultures were treated with plasmin, a proteolytic enzyme. These data support the hypothesis that bFGF is synthesized by chondrocytes and functions as an autocrine/paracrine mitogen via its deposition into the ECM with subsequent release from the ECM of cartilage being a critical step in biological activity. In addition, the study provides further evidence that locally produced bFGF plays an important role in normal growth and development of cartilage tissue. PMID:8872608

  1. Keratinocyte Migration in the Developing Eyelid Requires LIMK2

    PubMed Central

    Rice, Dennis S.; Hansen, Gwenn M.; Liu, Feng; Crist, Mike J.; Newhouse, Matthew M.; Potter, David; Xu, Nianhua; Abuin, Alejandro; Vogel, Peter J.; Zambrowicz, Brian P.

    2012-01-01

    In vitro studies have identified LIMK2 as a key downstream effector of Rho GTPase-induced changes in cytoskeletal organization. LIMK2 is phosphorylated and activated by Rho associated coiled-coil kinases (ROCKs) in response to a variety of growth factors. The biochemical targets of LIMK2 belong to a family of actin binding proteins that are potent modulators of actin assembly and disassembly. Although numerous studies have suggested that LIMK2 regulates cell morphology and motility, evidence supportive of these functions in vivo has remained elusive. In this study, a knockout mouse was created that abolished LIMK2 biochemical activity resulting in a profound inhibition of epithelial sheet migration during eyelid development. In the absence of LIMK2, nascent eyelid keratinocytes differentiate and acquire a pre-migratory phenotype but the leading cells fail to nucleate filamentous actin and remain immobile causing an eyes open at birth (EOB) phenotype. The failed nucleation of actin was associated with significant reductions in phosphorylated cofilin, a major LIMK2 biochemical substrate and potent modulator of actin dynamics. These results demonstrate that LIMK2 activity is required for keratinocyte migration in the developing eyelid. PMID:23071748

  2. Fibroblast Growth Factor Receptor and Platelet-Derived Growth Factor Receptor Abnormalities in Eosinophilic Myeloproliferative Disorders

    Microsoft Academic Search

    Nicholas C. P. Cross; Andreas Reiter

    2008-01-01

    Rearrangements of the genes encoding the fibroblast growth factor receptor 1 (FGFR1) and platelet-derived growth factor receptors (PDGFR) ? or ? receptor tyrosine kinases are found in a rare but important subset of patients with atypical myeloproliferative disorders that are usually but not always associated with eosinophilia. Chromosomal translocations or other rearrangements at 8p11–12, 4q12 or 5q31–33 give rise to

  3. Cytokine induction in human epidermal keratinocytes exposed to contact irritants and its relation to chemical-induced inflammation in mouse skin.

    PubMed

    Wilmer, J L; Burleson, F G; Kayama, F; Kanno, J; Luster, M I

    1994-06-01

    In response to exogenous stimuli such as phorbol-12-myristate 13-acetate, ultraviolet B radiation, and lipopolysaccharide, human keratinocytes produce soluble mediators that are important in primary contact irritancy including cytokines that are associated with proinflammatory properties (interleukin-1 alpha [IL-1 alpha], tumor necrosis factor alpha), chemotaxis (IL-8), and growth activation (granulocyte/macrophage colony stimulating factor, IL-6, transforming growth factor alpha). We examined qualitative and quantitative changes in selected intracellular and secreted cytokines in human keratinocyte cultures in response to non-sensitizing contact irritants (croton oil, sodium lauryl sulfate, methyl salicylate, ethyl phenylpropiolate), sensitizing irritants (oxazolone, dinitrofluorobenzene), and ulcerative agents (phenol, benzalkonium chloride, chromium trioxide). The chemicals were also applied to mouse skin to assess whether the chemical-specific pattern of inflammation correlated with the in vitro production of keratinocyte-derived cytokines. Although all agents elicited neutrophils to the site of chemical application, time dependent and chemical-specific patterns of inflammation could be detected. Sodium lauryl sulfate, phenol, and croton oil induced increases in IL-8 production at non-cytotoxic concentrations in semi-confluent human keratinocyte cultures. Phenol and croton oil stimulated tumor necrosis factor alpha production, whereas croton oil was the only agent found to induce granulocyte/macrophage colony-stimulating factor production. Croton oil, phenol, benzalkonium chloride, and dinitrofluorobenzene induced the intracellular production of IL-1 alpha without a concomitant release into the medium. The release of cytokines occurred in parallel with a relative increase in cytokine-specific mRNA transcripts. Studies using neutralizing antibodies to tumor necrosis factor alpha and IL-1 alpha demonstrated that IL-8 induction by croton oil and phenol occurred directly rather than through autocrine circuits. These data suggest that a given pattern of cytokine production is chemical-specific and may predict the contribution of keratinocytes to skin inflammation. PMID:8006454

  4. The suppression of fibroblast growth factor 2/fibroblast growth factor 4-dependent tumour angiogenesis and growth by the anti-growth factor activity of dextran derivative (CMDB7).

    PubMed Central

    Bagheri-Yarmand, R.; Kourbali, Y.; Mabilat, C.; Morère, J. F.; Martin, A.; Lu, H.; Soria, C.; Jozefonvicz, J.; Crépin, M.

    1998-01-01

    Our previous studies showed that carboxymethyl benzylamide dextran (CMDB7) blocks basic fibroblast growth factor (FGF-2)-dependent cell proliferation of a human breast epithelial line (HBL100), suggesting its potential role as a potent antiangiogenic substance. The derived cell line (HH9), which was transformed with the hst/FGF4 gene, has been shown to be highly proliferative in vitro and to induce angiogenic tumours in nude mice. We show here that CMDB7 inhibits the mitogenic activities of the conditioned media from HBL 100 and HH9 cells in a dose-dependent manner. When HH9 cells were injected s.c. into nude mice, CMDB7 treatment (300 mg kg(-1) week(-1)) suppressed the tumour take and the tumour growth by about 50% and 80% respectively. Immunohistochemical analysis showed a highly significant decrease, by more than threefold, in the endothelial density of viable tumour regions, together with a significant increase in the necrosis area. This antiangiogenic activity of CMDB7 was further demonstrated by direct inhibition of calf pulmonary artery (CPAE) and human umbilical vein (HUVEC) endothelial cell proliferation and migration in vitro. In addition, we showed that CMDB7 inhibits specifically the mitogenic effects of the growth factors that bind to heparin such as FGF-2, FGF-4, platelet-derived growth factor (PDGF-BB) and transforming growth factor (TGF-beta1), but not those of epidermal growth factor (EGF) and insulin-like growth factor (IGF-1). These results demonstrate that CMDB7 inhibits FGF-2/FGF-4-dependent tumour growth and angiogenesis, most likely by disrupting the autocrine and paracrine effects of growth factors released from the tumour cells. Images Figure 4 PMID:9662260

  5. Integrin ?6?4 and TRPV1 channel coordinately regulate directional keratinocyte migration.

    PubMed

    Miyazaki, Ayako; Ohkubo, Tsuyako; Hatta, Mitsutoki; Ishikawa, Hiroyuki; Yamazaki, Jun

    2015-02-27

    The directional migration of epithelial cells is crucial for wound healing. Among integrins, a family of cell adhesion receptors, integrin ?4 has been assumed to be a promigratory factor, in addition to its role in stable adhesion. In turn, Ca(2+) signaling is also a key coordinator of migration. Keratinocytes reportedly express transient receptor potential vanilloid channels (TRPV1); however, the function of these channels as a regulator of intracellular Ca(2+) level in cell migration has remained uncharacterized. In the present study, we investigated the role of TRPV1 in directional migration related to integrin ?4 using a scratch wound assay on a confluent monolayer sheet of murine keratinocytes (Pam212 cells). Double immunofluorescence staining revealed the de novo expression of integrin ?4 and TRPV1 in migrating cells at the wound edge in response to scratch wounding, and both expression levels were almost matched. Epidermal growth factor (EGF) not only promoted keratinocyte migration, but also caused the further up-regulation of both integrin ?4 and TRPV1. In addition, the knockdown of the integrin ?4 or TRPV1 gene significantly impeded wound closure. The TRPV1 agonist capsaicin significantly promoted migration, while a selective TRPV1 antagonist inhibited it. The gene knockdown of TRPV1 inhibited the expression of the integrin ?4 gene and that of ?4 protein in migrating cells. These findings suggest that TRPV1 may stimulate directional migration directly by eliciting a Ca(2+) signal or indirectly via integrin ?4 expression. PMID:25637531

  6. Basic Fibroblastic Growth Factor as a Potential Meningeal Angiogenic Factor

    PubMed Central

    Olson, Jeffrey J.; Reisner, Andrew; Klemm, Joyce M.; Bakay, Roy A. E.

    1993-01-01

    Vascular supply plays a significant role in the management of skull base tumors. The diagnosis is aided by contrast-enhanced imaging and angiographic techniques, and embolization procedures are used to devascularize certain lesions. The degree of surgical technical difficulty is strongly influenced by the degree of tumor vascularity. Although the importance of this blood supply is clearly understood, the mechanism involved in developing a system of tumor-perfusing vessels is yet to be defined. The development of a vascular network, or angiogenesis, is an important event in allowing tumor proliferation to progress beyond small clusters of cells. Basic fibroblastic growth factor (bFGF) is an especially attractive candidate as an angiogenic growth factor because of its ability to stimulate processes that are characteristic of angiogenesis in vitro. Tumors that involve the meninges may have the ability to liberate normally stored bFGF, which may, in turn, induce new vessel formation for continued tumor proliferation. An immunohistochemical analysis of rodent and bovine meninges to study this phenomenon is described. The dura, arachnoid, and their associated vessels are shown clearly to contain this growth factor. Ultimately, an adjuvant therapy based on the inhibition of angiogenesis may provide a reasonable alternative to aggressive surgical approaches in skull base tumors that are incompletely resectable. ImagesFigure 1Figure 2 PMID:17170900

  7. Production of a novel fibroblast-populated platelet matrix cocultured with keratinocytes.

    PubMed

    Schuster, Kevin M; Martens, Matthew; Goldenberg, Marat; Tai, Chau; Strande, Louise; Hewitt, Charles W

    2007-07-01

    We have developed a new method for the production of a dermal matrix equivalent. Human platelets were used to dilute human fibroblasts. The platelet mix was placed in a cell culture well. Addition of 200 microL of a thrombin solution caused gel formation. Gels were overlaid with standard Iscove's growth medium supplemented with 10% fetal bovine serum, insulin, and N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid buffer. Medium was exchanged regularly. Keratinocytes were plated on top of selected gels and elevated to the air-liquid interface. The gels were harvested weekly, fixed, cut, and stained with hematoxylin and eosin stains and immunostains for collagens I, III, and IV and cytokeratins. Digital image analysis was used to quantitate collagen production. Growth factors, including transforming growth factor-beta (TGF-beta), platelet-derived growth factor, and vitamin C were added. Staining identified fibroblasts within the gels with a surrounding fibrous matrix. Immunostaining for cytokeratin identified keratinocytes on the gel surface. Immunostaining revealed the fibrous matrix to be composed of collagen I and III and some collagen IV. Digital image analysis demonstrated that greater TGF-beta concentration resulted in greater collagen production. These differences were statistically significant. With development of this construct, a viable dermal/epidermal replacement may be possible. TGF-beta enhances collagen production by fibroblasts in this matrix. PMID:17518711

  8. Synergistic effect of transforming growth factor beta and fibroblast growth factor on DNA synthesis in chick growth plate chondrocytes.

    PubMed

    Crabb, I D; O'Keefe, R J; Puzas, J E; Rosier, R N

    1990-11-01

    Transforming growth factor beta and fibroblast growth factor are mitogens for chick growth plate chondrocytes. TGF-beta stimulated a 3.5-fold increase, and FGF a 13.5-fold increase in the rate of thymidine incorporation after a 24 h exposure. TGF-beta and FGF were synergistic in chondrocytes, causing a 73-fold stimulation in thymidine incorporation compared with control. This synergistic response was not dependent upon the simultaneous presence of both mitogens. Sequential exposure of chondrocytes to TGF-beta and FGF in either order reproduced in large part the synergistic interaction observed when both growth factors were present simultaneously. The time required for induction of the subsequent synergistic response was brief and, in the case of TGF-beta, corresponded to the time required for [125I]TGF-beta receptor binding. EGF and PDGF were not mitogenic for chondrocytes, and neither of these factors enhanced the response of the cells to either TGF-beta or FGF. Finally, TGF-beta and FGF did not, either alone or in combination, elevate intracellular cAMP levels. These results emphasize the importance of examining growth factor effects in the context of other growth regulators. Furthermore, this specific and dramatic synergistic stimulation of thymidine incorporation may provide a useful tool in elucidating the mitogenic mechanism of the individual growth factors. PMID:2270774

  9. Keratinocyte Migration and a Hypothetical New Role for Extracellular Heat Shock Protein 90 Alpha in Orchestrating Skin Wound Healing

    PubMed Central

    Woodley, David T.; Wysong, Ashley; DeClerck, Brittany; Chen, Mei; Li, Wei

    2015-01-01

    Significance: The treatment and care of patients with skin wounds are a major healthcare expenditure. Burn wounds, iatrogenic surgical wounds, venous stasis dermatitis ulcers, diabetic lower limb ulcers, pressure ulcers, and skin wounds from peripheral neuropathies are largely treated with only supportive care. Despite a great deal of research into using growth factors as therapeutic agents, to date, the field has been disappointing. The only biologic agent that is Federal Drug Administration (FDA) approved for promoting skin wound healing is recombinant platelet-derived growth factor (PDGF-BB), but its modest efficacy and expense limit its use clinically. Recent Advances: Acute hypoxia induced by the clotting of dermal blood vessels during the wounding of skin is a major stress factor that leads to the re-programming of basal keratinocytes to initiate re-epithelialization. The laterally migrating keratinocytes secrete extracellular heat shock protein 90 alpha. Heat shock protein 90 alpha (hsp90?) engages low-density lipoprotein receptor-related protein-1 (LRP-1) cellular receptors and works as an autocrine factor to stimulate keratinocyte migration (re-epithelialization) and as a paracrine factor to stimulate the migration of dermal fibroblasts (fibroplasia) and microvascular endothelial cells (neo-vascularization). Hypoxia-triggered extracellular heat shock protein 90 alpha acts as the master regulator of initial skin wound healing. Critical Issues: It is not yet known how the engagement of hsp90? with the LRP-1 receptor leads to increased motility of keratinocytes, fibroblasts, or microvascular endothelial cells. Understanding the sequence of how an acute skin wound via hypoxic stress leads to cellular events that ultimately induce accelerated wound closure provides numerous targets for new wound-healing therapeutic agents. Future Directions: Developing data for an investigational new drug (IND) application to the FDA for a Phase I study using hsp90? in human skin wounds. Identifying the cellular signaling mechanisms by which hsp90? enhances skin cell migration, leading to accelerated wound closure. PMID:25945283

  10. Regulation of Transforming Growth Factor ? Expression in a Growth Factor-Independent Cell Line

    PubMed Central

    Howell, Gillian M.; Humphrey, Lisa E.; Ziober, Barry L.; Awwad, Rana; Periyasamy, Basker; Koterba, Alan; Li, Wenhui; Willson, James K. V.; Coleman, Kevin; Carboni, Joan; Lynch, Mark; Brattain, Michael G.

    1998-01-01

    Aberrant transcriptional regulation of transforming growth factor ? (TGF?) appears to be an important contributor to the malignant phenotype and the growth factor independence with which malignancy is frequently associated. However, little is known about the molecular mechanisms responsible for dysregulation of TGF? expression in the malignant phenotype. In this paper, we report on TGF? promoter regulation in the highly malignant growth factor-independent cell line HCT116. The HCT116 cell line expresses TGF? and the epidermal growth factor receptor (EGFR) but is not growth inhibited by antibodies to EGFR or TGF?. However, constitutive expression of TGF? antisense RNA in the HCT116 cell line resulted in the isolation of clones with markedly reduced TGF? mRNA and which were dependent on exogenous growth factors for proliferation. We hypothesized that if TGF? autocrine activation is the major stimulator of TGF? expression in this cell line, TGF? promoter activity should be reduced in the antisense TGF? clones in the absence of exogenous growth factor. This was the case. Moreover, transcriptional activation of the TGF? promoter was restored in an antisense-TGF?-mRNA-expressing clone which had reverted to a growth factor-independent phenotype. Using this model system, we were able to identify a 25-bp element within the TGF? promoter which conferred TGF? autoregulation to the TGF? promoter in the HCT116 cell line. In the TGF?-antisense-RNA-expressing clones, this element was activated by exogenous EGF. This 25-bp sequence contained no consensus sequences of known transcription factors so that the TGF? or EGF regulatory element within this 25-bp sequence represents a unique element. Further characterization of this 25-bp DNA sequence by deletion analysis revealed that regulation of TGF? promoter activity by this sequence is complex, as both repressors and activators bind in this region, but the overall expression of the activators is pivotal in determining the level of response to EGF or TGF? stimulation. The specific nuclear proteins binding to this region are also regulated in an autocrine-TGF?-dependent fashion and by exogenous EGF in EGF-deprived TGF? antisense clone 33. This regulation is identical to that seen in the growth factor-dependent cell line FET, which requires exogenous EGF for optimal growth. Moreover, the time response of the stimulation of trans-acting factor binding by EGF suggests that the effect is directly due to growth factor and not mediated by changes in growth state. We conclude that this element appears to represent the major positive regulator of TGF? expression in the growth factor-independent HCT116 cell line and may represent the major site of transcriptional dysregulation of TGF? promoter activity in the growth factor-independent phenotype. PMID:9418877

  11. Hepatocyte growth factor is a potent angiogenic factor which stimulates endothelial cell motility and growth

    Microsoft Academic Search

    F. Bussolino; M. E Di Renzo; M. Ziche; E. Bocchietto; M. Olivero; L. Naldini; G. Gaudino; L. Tamagnone; A. Coffer; P. M. Comoglio

    1992-01-01

    Hepatocyte Growth Factor (HGF, also known as Scatter Factor) is a powerful mitogen or motility factor in different cells, acting through the tyrosine kinase receptor encoded by the MET proto- oncogene. Endothelial cells express the MET gene and expose at the cell surface the mature protein (p190 MEt) made of a 50 kD (o0 subunit disulfide linked to a 145-kD

  12. The Role of Growth Factors in Experimental Autoimmune Encephalomyelitis

    Microsoft Academic Search

    Amy E. Lovett-Racke; Michael K. Racke

    This chapter reviews the research done on the role of growth factor in experimental autoimmune encephalomyelitis and demonstrates\\u000a the increasingly recognized therapeutic potential of growth factors in inflammatory demyelinating disease.

  13. A FoxO–Smad synexpression group in human keratinocytes

    PubMed Central

    Gomis, Roger R.; Alarcón, Claudio; He, Wei; Wang, Qiongqing; Seoane, Joan; Lash, Alex; Massagué, Joan

    2006-01-01

    Transforming growth factor ? (TGF-?) signals through activation of Smad transcription factors. Activated Smad proteins associate with different DNA-binding cofactors for the recognition and regulation of specific target genes. Members of the forkhead box O family (FoxO1, FoxO3, and FoxO4) play such a role in the induction of the cyclin-dependent kinase inhibitors p15Ink4b and p21Cip1. To delineate the organization of the TGF-? response in human keratinocytes, we defined the set of genes whose activation by TGF-? requires both FoxO and Smad functions. FoxO factors are shown to be essential for 11 of the 115 immediate gene activation responses to TGF-? in these cells. FoxO1, FoxO3, and FoxO4 act redundantly as mediators of these effects. Smad4, which functions as a partner of receptor-phosphorylated Smad2/3, is required for all of these responses. These results define a FoxO–Smad synexpression group or group of genes that are jointly induced by a common mechanism in response to TGF-?. In addition to p15INK4b and p21CIP1, these genes include mediators of stress responses (GADD45A, GADD45B, and IER1) and adaptive cell signaling responses (CTGF, JAG1, LEMD3, SGK, CDC42EP3, and OVOL1). Bioinformatic analysis of the promoter region of these genes reveals diverse configurations of Smad and FoxO binding elements, implying differences in the regulatory properties of this group of genes. Indeed, a subset of FoxO/Smad-dependent TGF-? gene responses additionally require the transcription factor CCAAT/enhancer-binding protein ?. The composition of the FoxO–Smad synexpression group suggests that stress reactions and adaptive functions accompany the cytostatic response of keratinocytes to TGF-?. PMID:16908841

  14. Cytokines and growth factors in atherogenesis.

    PubMed

    Clinton, S K; Libby, P

    1992-12-01

    The development of laboratory techniques for the culturing of vascular endothelial and smooth-muscle cells during the 1970s, followed by the rapid advances in molecular and cell biology during the 1980s, provided the foundation for the identification of growth factor and cytokine networks involved in maintenance of the normal vasculature as well as participating in diverse pathologic processes involving blood vessels. Vascular cells can produce and respond to a vast array of biochemical messengers that control cell replication, differentiation, and many specific cell functions. Investigators are beginning to explore the changes in the patterns of messengers exchanged between the vascular cells and infiltrating leukocytes during the initiation and progression of atherosclerosis. A variety of in vitro and in vivo studies have indicated that growth factors and cytokines that mediate the critical processes of inflammation and wound healing also play a central role in vascular disease. Indeed, many view atherosclerosis as the result of excessive or prolonged chronic inflammation and wound healing in response to diverse injurious stimuli to cells of the vessel wall. Vascular injury may result from many varied and interacting forces, including nutritional and metabolic abnormalities such as hyperlipidemias or elevated homocysteine, mechanical forces associated with hypertension, exogenous toxins including those found in cigarette smoke, abnormally glycated proteins associated with diabetes mellitus, oxidatively modified lipids or proteins, and, possibly, viral infections. Ultimately, a greater understanding of the activated cytokine and growth factor networks within the vascular wall following injury and during atherogenesis will allow clinical scientists to identify steps susceptible to therapeutic intervention using recombinant cytokines, antibodies, soluble receptors, or receptor antagonists. Other therapeutic strategies may involve the transfection of specific genes, which may inhibit atherosclerosis, into vascular cells at sites prone to lesion formation. PMID:1456874

  15. Hepatocyte growth factor in renal failure: Promise and reality

    Microsoft Academic Search

    Gustavo A Vargas; Andreas Hoeflich; Peter M Jehle

    2000-01-01

    Hepatocyte growth factor in renal failure: Promise and reality. Can science discover some secrets of Greek mythology? In the case of Prometheus, we can now suppose that his amazing hepatic regeneration was caused by a peptide growth factor called hepatocyte growth factor (HGF). Increasing evidence indicates that HGF acts as a multifunctional cytokine on different cell types. This review addresses

  16. Osteonecrosis of the femoral head: treatment with ancillary growth factors.

    PubMed

    Houdek, Matthew T; Wyles, Cody C; Sierra, Rafael J

    2015-09-01

    Osteonecrosis (ON) of the femoral head, also known as avascular necrosis (AVN) of the femoral head, is a progressive disease that predominantly affects younger patients. During early stage of ON, decompression of the femoral head has been commonly used to improve pain. The decompression has been augmented with nonvascularized or vascularized bone grafts, mesenchymal stems cells, and growth factors. The use of adjuvant growth factors to supplement the core decompression has mainly been limited to animal models in an attempt to regenerate the necrotic lesion of ON. Factors utilized include bone morphogenetic proteins, vascular endothelial growth factors, hepatocyte growth factors, fibroblast growth factors, granulocyte colony-stimulating factors, and stem cells factors. In animal models, the use of these factors has been shown to increase bone formation and angiogenesis. Although promising, the use of these growth factors and cell-based therapies clinically remains limited. PMID:25985987

  17. Exogenous addition of a C-xylopyranoside derivative stimulates keratinocyte dermatan sulfate synthesis and promotes migration.

    PubMed

    Muto, Jun; Naidu, Nandita Natasha; Yamasaki, Kenshi; Pineau, Nathalie; Breton, Lionel; Gallo, Richard L

    2011-01-01

    As C-Xyloside has been suggested to be an initiator of glycosaminoglycan (GAG) synthesis, and GAGs such as Dermatan sulfate (DS) are potent enhancers of fibroblast growth factor (FGF)--10 action, we investigated if a C-Xylopyranoside derivative, (C-?-D-xylopyranoside-2-hydroxy-propane, C-Xyloside), could promote DS production by cultured normal human keratinocytes, how this occurs and if C-Xyloside could also stimulate FGF-dependent cell migration and proliferation. C-Xyloside-treated keratinocytes greatly increased secretion of total sulfated GAGs. Majority of the induced GAG was chondroitin sulfate/dermatan sulfate (CS/DS) of which the major secreted GAG was DS. Cells lacking xylosyltransferase enzymatic activity demonstrated that C-Xyloside was able to stimulate GAG synthesis without addition to core proteins. Consistent with the observed increase in DS, keratinocytes treated with C-Xyloside showed enhanced migration in response to FGF-10 and secreted into their culture media GAGs that promoted FGF-10-dependent cellular proliferation. These results indicate that C-Xyloside may enhance epithelial repair by serving as an initiator of DS synthesis. PMID:21998662

  18. Effects of recombinant basic fibroblast growth factor, insulin-like growth factor-II and transforming growth factor- ? 1 on dog dental pulp cells in vivo

    Microsoft Academic Search

    D. Tziafas; A. Alvanou; S. Papadimitriou; J. Gasic; A. Komnenou

    1998-01-01

    The effects of recombinant basic fibroblast growth factor (bFGF), insulin-like growth factor (IGF)-II and transforming growth factor (TGF)-?1 on dental pulp cells were investigated by light and transmission electron microscopy after their implantation for 1 and 3 weeks at central sites of mechanically exposed pulps in dog molar and canine teeth. The implants were Millipore filters that have been soaked

  19. Shuttling of the autoantigen La between nucleus and cell surface after uv irradiation of human keratinocytes

    SciTech Connect

    Bachmann, M.; Chang, S.; Slor, H.; Kukulies, J.; Mueller, W.E. (Universitaet, Mainz (Germany, F.R.))

    1990-12-01

    During the past years we have established that the nuclear autoantigen La shuttles between the nucleus and the cytoplasm in tumor cells after inhibition of transcription or virus infection. We reinvestigated this shuttling using primary human keratinocytes from both healthy donors and patients with xeroderma pigmentosum. Ultraviolet irradiation resulted in both an inhibition of transcription and a translocation of La protein from the nucleus to the cytoplasm. After a prolonged inhibition of transcription La protein relocated into the nucleus and assembled with nuclear storage regions. The uv-induced shuttling included a translocation to the cell surface, where La protein colocalized with epidermal growth factor receptors.

  20. Sequential delivery of basic fibroblast growth factor and platelet-derived growth factor for angiogenesis.

    PubMed

    Tengood, Jillian E; Ridenour, Ryan; Brodsky, Ross; Russell, Alan J; Little, Steven R

    2011-05-01

    An externally regulated delivery model that permits temporal separation of multiple angiogenic factors was used for the delivery of basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF). While bFGF plays a significant role in the sprouting of new capillaries, PDGF plays a role in the recruitment of mural cells, which stabilize neovessels. However, these two factors have been shown to inhibit each other, when presented together. Using the externally regulated model, sequential delivery of bFGF and PDGF led to not only increased endothelial cell migration, but also endothelial cell and vascular pericyte colocalization. More importantly, this delivery strategy was able to induce red blood cell-filled neovessels, suggesting integration of angiogenesis with the existing vasculature. PMID:21142700

  1. Vascular endothelial growth-factor production is stimulated in response to growth-factors in human glioma-cells.

    PubMed

    Koochekpour, S; Merzak, A; Pilkington, G

    1995-11-01

    Neovascularization is essential for tumour growth and is mediated by physiological substances produced by tumours. Vascular endothelial growth factor (VEGF) is one such potent angiogenic factor. Human gliomas, the most important class of intrinsic brain tumours, express VEGF both in vivo and in vitro. Factors involved in the control of VEGF production by glioma cells are not well known. In this study, we investigated the role of basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), and platelet derived growth factors (PDGF) on VEGF production by four different glioma cell lines in vitro. With the exception of PDGF A/A and B/B in one cell line, all growth factors differentially stimulated VEGF production in all cell lines investigated. These data suggest that VEGF production in human glioma may be regulated by other growth factors which are also known to be expressed in such tumours. PMID:21597853

  2. Keratinocyte galvanotaxis in combined DC and AC electric fields supports an electromechanical transduction sensing mechanism.

    PubMed

    Hart, Francis X; Laird, Mhairi; Riding, Aimie; Pullar, Christine E

    2013-02-01

    Sedentary keratinocytes at the edge of a skin wound migrate into the wound, guided by the generation of an endogenous electric field (EF) generated by the collapse of the transepithelial potential. The center of the wound quickly becomes more negative than the surrounding tissue and remains the cathode of the endogenous EF until the wound is completely re-epithelialized. This endogenous guidance cue can be studied in vitro. When placed in a direct current (DC) EF of physiological strength, 100 V/m, keratinocytes migrate directionally toward the cathode in a process known as galvanotaxis. Although a number of membrane-bound (e.g., epidermal growth factor receptor (EGFR), integrins) and cytosolic proteins (cAMP, ERK, PI3K) are known to play a role in the downstream signaling mechanisms underpinning galvanotaxis, the initial sensing mechanism for this response is not understood. To investigate the EF sensor, we studied the migration of keratinocytes in a DC EF of 100 V/m, alternating current (AC) EFs of 40 V/m at either 1.6 or 160 Hz, and combinations of DC and AC EFs. In the AC EFs alone, keratinocytes migrated randomly. The 1.6 Hz AC EF combined with the DC EF suppressed the direction of migration but had no effect on speed. In contrast, the 160 Hz AC EF combined with the DC EF did not affect the direction of migration but increased the migration speed compared to the DC EF alone. These results can be understood in terms of an electromechanical transduction model, but not an electrodiffusion/osmosis or a voltage-gated channel model. PMID:22907479

  3. Biological Activity of a Growth Factor for Ovarian Cells

    PubMed Central

    Jones, Kenneth L.; Gospodarowicz, Denis

    1974-01-01

    The biological activity of a protein growth factor is described. This factor was isolated from bovine pituitary tissue, and its activity was tested on cells of rat ovarian origin. Activity was assayed as growth-promoting potential measured by cell counts and is concentrationdependent. Similar growth stimulation was not produced by several cyclic nucleotides tested, neither was there crossreactivity between this growth factor and a chemically similar one produced by rat liver cells. Images PMID:4372617

  4. Expression of Epidermal Growth Factor and Epidermal Growth Factor Receptor Immunoreactivity in the Asthmatic Human Airway

    Microsoft Academic Search

    MASARU AMISHIMA; MITSURU MUNAKATA; YASUYUKI NASUHARA; ATSUKO SATO; TORU TAKAHASHI; YUKIHIKO HOMMA; YOSHIKAZU KAWAKAMI

    1998-01-01

    Chronic airway inflammation, one of the pathophysiologic features of bronchial asthma, is suspected to be responsible for irreversible pathological changes of airways, called airway remodeling . To exam- ine the mechanisms of airway remodeling in asthma, we investigated the expression of epidermal growth factor (EGF) and its receptor immunohistochemically in asthmatic human airways. Airway specimens from seven patients with asthma

  5. Cholinergic Transactivation of the EGFR in HaCaT Keratinocytes Stimulates a Flotillin-1 Dependent MAPK-Mediated Transcriptional Response

    PubMed Central

    Kühne, Sina; Ockenga, Wymke; Banning, Antje; Tikkanen, Ritva

    2015-01-01

    Acetylcholine and its receptors regulate numerous cellular processes in keratinocytes and other non-neuronal cells. Muscarinic acetylcholine receptors are capable of transactivating the epidermal growth factor receptor (EGFR) and, downstream thereof, the mitogen-activated protein kinase (MAPK) cascade, which in turn regulates transcription of genes involved in cell proliferation and migration. We here show that cholinergic stimulation of human HaCaT keratinocytes results in increased transcription of matrix metalloproteinase MMP-3 as well as several ligands of the epidermal growth factor family. Since both metalloproteinases and the said ligands are involved in the transactivation of the EGFR, this transcriptional upregulation may provide a positive feed-forward loop for EGFR/MAPK activation. We here also show that the cholinergic EGFR and MAPK activation and the upregulation of MMP-3 and EGF-like ligands are dependent on the expression of flotillin-1 which we have previously shown to be a regulator of MAPK signaling. PMID:25803106

  6. Gene Expression of Growth Factors and Growth Factor Receptors for Potential Targeted Therapy of Canine Hepatocellular Carcinoma

    PubMed Central

    IIDA, Gentoku; ASANO, Kazushi; SEKI, Mamiko; SAKAI, Manabu; KUTARA, Kenji; ISHIGAKI, Kumiko; KAGAWA, Yumiko; YOSHIDA, Orie; TESHIMA, Kenji; EDAMURA, Kazuya; WATARI, Toshihiro

    2013-01-01

    ABSTRACT The purpose of this study was to evaluate the gene expression of growth factors and growth factor receptors of primary hepatic masses, including hepatocellular carcinoma (HCC) and nodular hyperplasia (NH), in dogs. Quantitative real-time reverse transcriptase-polymerase chain reaction was performed to measure the expression of 18 genes in 18 HCCs, 10 NHs, 11 surrounding non-cancerous liver tissues and 4 healthy control liver tissues. Platelet-derived growth factor-B (PDGF-B), transforming growth factor-?, epidermal growth factor receptor, epidermal growth factor and hepatocyte growth factor were found to be differentially expressed in HCC compared with NH and the surrounding non-cancerous and healthy control liver tissues. PDGF-B is suggested to have the potential to become a valuable ancillary target for the treatment of canine HCC. PMID:24189579

  7. Gene expression of growth factors and growth factor receptors for potential targeted therapy of canine hepatocellular carcinoma.

    PubMed

    Iida, Gentoku; Asano, Kazushi; Seki, Mamiko; Sakai, Manabu; Kutara, Kenji; Ishigaki, Kumiko; Kagawa, Yumiko; Yoshida, Orie; Teshima, Kenji; Edamura, Kazuya; Watari, Toshihiro

    2014-03-01

    The purpose of this study was to evaluate the gene expression of growth factors and growth factor receptors of primary hepatic masses, including hepatocellular carcinoma (HCC) and nodular hyperplasia (NH), in dogs. Quantitative real-time reverse transcriptase-polymerase chain reaction was performed to measure the expression of 18 genes in 18 HCCs, 10 NHs, 11 surrounding non-cancerous liver tissues and 4 healthy control liver tissues. Platelet-derived growth factor-B (PDGF-B), transforming growth factor-?, epidermal growth factor receptor, epidermal growth factor and hepatocyte growth factor were found to be differentially expressed in HCC compared with NH and the surrounding non-cancerous and healthy control liver tissues. PDGF-B is suggested to have the potential to become a valuable ancillary target for the treatment of canine HCC. PMID:24189579

  8. Toxicities of the thrombopoietic growth factors

    PubMed Central

    Cuker, Adam

    2010-01-01

    The thrombopoietic growth factors (TGFs) are a novel class of compounds for the treatment of chronic immune thrombocytopenia (ITP). The first of these agents to receive regulatory approval, romiplostim and eltrombopag, have demonstrated impressive efficacy and tolerability in randomized controlled trials and open-label extension studies of several years duration and stand poised to revolutionize the management of ITP. Nonetheless, critical questions regarding the safety of these agents, particularly after long-term administration, remain partially unanswered. The objective of this review is to describe the reported and potential toxicities of the TGFs including bone marrow fibrosis, thrombosis, rebound thrombocytopenia, hematologic malignancy, neutralizing antibody formation, hepatotoxicity, cataract formation, and common adverse events. The incidence and clinical implications of these toxicities as well as strategies for patient safety monitoring are examined. PMID:20620441

  9. Fibroblast growth factor 23 and bone mineralisation.

    PubMed

    Guo, Yu-Chen; Yuan, Quan

    2015-03-01

    Fibroblast growth factor 23 (FGF23) is a hormone that is mainly secreted by osteocytes and osteoblasts in bone. The critical role of FGF23 in mineral ion homeostasis was first identified in human genetic and acquired rachitic diseases and has been further characterised in animal models. Recent studies have revealed that the levels of FGF23 increase significantly at the very early stages of chronic kidney disease (CKD) and may play a critical role in mineral ion disorders and bone metabolism in these patients. Our recent publications have also shown that FGF23 and its cofactor, Klotho, may play an independent role in directly regulating bone mineralisation instead of producing a systematic effect. In this review, we will discuss the new role of FGF23 in bone mineralisation and the pathophysiology of CKD-related bone disorders. PMID:25655009

  10. Growth hormone, insulinlike growth factor-1, and insulinlike growth factor binding proteins 1 and 3 in chronic liver disease

    Microsoft Academic Search

    Anthony Donaghy; Richard Ross; Alexander Gimson; Sian Cwyfan Hughes; Jeffrey Holly; Roger Williams

    1995-01-01

    The liver is the major source of circulating insulinlike growth factor-I (IGF-I) and has been suggested as a major source of at least two of the major binding proteins that modify its bioavailability. We aimed to assess the direct effects of liver dysfunction on serum levels of IGF1 and its major binding proteins by measuring fasting levels of growth hormone,

  11. The Fibroblast Growth Factor signaling pathway

    PubMed Central

    Ornitz, David M; Itoh, Nobuyuki

    2015-01-01

    The signaling component of the mammalian Fibroblast Growth Factor (FGF) family is comprised of eighteen secreted proteins that interact with four signaling tyrosine kinase FGF receptors (FGFRs). Interaction of FGF ligands with their signaling receptors is regulated by protein or proteoglycan cofactors and by extracellular binding proteins. Activated FGFRs phosphorylate specific tyrosine residues that mediate interaction with cytosolic adaptor proteins and the RAS-MAPK, PI3K-AKT, PLC?, and STAT intracellular signaling pathways. Four structurally related intracellular non-signaling FGFs interact with and regulate the family of voltage gated sodium channels. Members of the FGF family function in the earliest stages of embryonic development and during organogenesis to maintain progenitor cells and mediate their growth, differentiation, survival, and patterning. FGFs also have roles in adult tissues where they mediate metabolic functions, tissue repair, and regeneration, often by reactivating developmental signaling pathways. Consistent with the presence of FGFs in almost all tissues and organs, aberrant activity of the pathway is associated with developmental defects that disrupt organogenesis, impair the response to injury, and result in metabolic disorders, and cancer. © 2015 Wiley Periodicals, Inc. PMID:25772309

  12. The Fibroblast Growth Factor signaling pathway.

    PubMed

    Ornitz, David M; Itoh, Nobuyuki

    2015-01-01

    The signaling component of the mammalian Fibroblast Growth Factor (FGF) family is comprised of eighteen secreted proteins that interact with four signaling tyrosine kinase FGF receptors (FGFRs). Interaction of FGF ligands with their signaling receptors is regulated by protein or proteoglycan cofactors and by extracellular binding proteins. Activated FGFRs phosphorylate specific tyrosine residues that mediate interaction with cytosolic adaptor proteins and the RAS-MAPK, PI3K-AKT, PLC?, and STAT intracellular signaling pathways. Four structurally related intracellular non-signaling FGFs interact with and regulate the family of voltage gated sodium channels. Members of the FGF family function in the earliest stages of embryonic development and during organogenesis to maintain progenitor cells and mediate their growth, differentiation, survival, and patterning. FGFs also have roles in adult tissues where they mediate metabolic functions, tissue repair, and regeneration, often by reactivating developmental signaling pathways. Consistent with the presence of FGFs in almost all tissues and organs, aberrant activity of the pathway is associated with developmental defects that disrupt organogenesis, impair the response to injury, and result in metabolic disorders, and cancer. For further resources related to this article, please visit the WIREs website. PMID:25772309

  13. Diindolylmethane alters gene expression in human keratinocytes in vitro.

    PubMed

    Carter, Timothy H; Liu, Kai; Ralph, Walter; Chen, DaZhi; Qi, Mei; Fan, Saijun; Yuan, Fang; Rosen, Eliot M; Auborn, Karen J

    2002-11-01

    Indole-3-carbinol (I3C) and its dimer 3,3'-diindolylmethane (DIM), obtained from dietary consumption of cruciferous vegetables, have multiple biochemical activities. Both compounds have been effective clinically in treating precancerous lesions of the cervix and laryngeal papillomas, pathologies with a human papillomavirus (HPV) component. Using cDNA microarrays, we examined early changes in gene expression after treatment with 100 micro mol/L DIM in C33A and CaSki cervical cancer cells and in an immortalized human epithelial cell line (HaCat), as well as in normal human foreskin keratinocytes (HFK). Multiple analyses were done after treating C33A cells for 6 h; other analyses included 4- and 12-h treatments of C33A and 6-h treatments of CaSki, HaCat and HFK cells. DIM consistently altered the expression of >100 genes at least twofold. Many of the stimulated genes encode transcription factors and proteins involved in signaling, stress response and growth. Results were comparable between transformed cells with and without integrated HPV sequences, and many of the same genes were induced in these cancer-derived cells and in noncancer cells. Eight genes encoding bZip proteins were among the most consistently and robustly induced, including the stress-associated immediate early gene GADD153 (>50 fold in C33A) and nuclear factor-interleukin 6 (NF-IL6), also known as c/EBPbeta, (>5 fold in C33A), which has been shown to reduce expression of HPV oncogenes. Induction of GADD153, NF-IL6 and ATF3 was confirmed by Western analysis. In functional analyses, DIM not only suppressed transcription of a luciferase gene driven by the HPV11 upstream regulatory region (URR) in C33A, CaSki, HaCat and HFK cells from >2-fold to 37-fold depending on the type of cells, but also reduced endogenous transcription of HPV16 oncogenes to undetectable levels in CaSki cells as determined by an RNase protection assay. Ectopic expression of GADD153 or NF-IL6 suppressed transcription in a dose-dependent manner driven by the HPV11 URR in C33A, CaSki, HaCat and HFK cells. These results identify unexpected ways in which dietary I3C and DIM invoke cellular responses and are consistent with a potential antiviral effect of DIM on keratinocytes, but they do not explain the differential sensitivity of transformed keratinocytes to apoptosis by DIM. PMID:12421845

  14. Transforming growth factor-? pathway activity in glioblastoma

    PubMed Central

    Tritschler, Isabel; Schroeder, Judith Johanna; Espinoza, Larisa; Rushing, Elisabeth Jane; Weller, Michael

    2015-01-01

    Transforming growth factor (TGF)-? is a central molecule maintaining the malignant phenotype of glioblastoma. Anti-TGF-? strategies are currently being explored in early clinical trials. Yet, there is little contemporary data on the differential expression of TGF-? isoforms at the mRNA and protein level or TGF-?/Smad pathway activity in glioblastomas in vivo. Here we studied 64 newly diagnosed and 16 recurrent glioblastomas for the expression of TGF-?1-3, platelet-derived growth factor (PDGF)-B, and plasminogen activator inhibitor (PAI)-1 mRNA by RT-PCR and for the levels of TGF-?1-3 protein, phosphorylated Smad2 (pSmad2), pSmad1/5/8 and PAI-1 by immunohistochemistry. Among the TGF-? isoforms, TGF-?1 mRNA was the most, whereas TGF-?3 mRNA was the least abundant. TGF-?1-3 mRNA expression was strongly correlated, as was the expression of TGF-?1-3 mRNA, and of the TGF-?1-3 target genes, PDGF-B and PAI-1. TGF-?2 and TGF-?3 protein levels correlated well, whereas the comparison of the other TGF-?isoforms did not. Positive correlation was also observed between TGF-?1 and pSmad1/5/8 and between pSmad2 and pSmad1/5/8. Survival analyses indicated that a group of patients with high expression levels of TGF-?2 mRNA or pSmad1/5/8 protein have inferior outcome. We thus provide potential biomarkers for patient stratification in clinical trials of anti-TGF-? therapies in glioblastoma. PMID:25849941

  15. Agent Based Modelling Helps in Understanding the Rules by Which Fibroblasts Support Keratinocyte Colony Formation

    PubMed Central

    Sun, Tao; McMinn, Phil; Holcombe, Mike; Smallwood, Rod; MacNeil, Sheila

    2008-01-01

    Background Autologous keratincoytes are routinely expanded using irradiated mouse fibroblasts and bovine serum for clinical use. With growing concerns about the safety of these xenobiotic materials, it is desirable to culture keratinocytes in media without animal derived products. An improved understanding of epithelial/mesenchymal interactions could assist in this. Methodology/Principal Findings A keratincyte/fibroblast o-culture model was developed by extending an agent-based keratinocyte colony formation model to include the response of keratinocytes to both fibroblasts and serum. The model was validated by comparison of the in virtuo and in vitro multicellular behaviour of keratinocytes and fibroblasts in single and co-culture in Greens medium. To test the robustness of the model, several properties of the fibroblasts were changed to investigate their influence on the multicellular morphogenesis of keratinocyes and fibroblasts. The model was then used to generate hypotheses to explore the interactions of both proliferative and growth arrested fibroblasts with keratinocytes. The key predictions arising from the model which were confirmed by in vitro experiments were that 1) the ratio of fibroblasts to keratinocytes would critically influence keratinocyte colony expansion, 2) this ratio needed to be optimum at the beginning of the co-culture, 3) proliferative fibroblasts would be more effective than irradiated cells in expanding keratinocytes and 4) in the presence of an adequate number of fibroblasts, keratinocyte expansion would be independent of serum. Conclusions A closely associated computational and biological approach is a powerful tool for understanding complex biological systems such as the interactions between keratinocytes and fibroblasts. The key outcome of this study is the finding that the early addition of a critical ratio of proliferative fibroblasts can give rapid keratinocyte expansion without the use of irradiated mouse fibroblasts and bovine serum. PMID:18461132

  16. Design of growth factor sequestering biomaterials.

    PubMed

    Belair, David G; Le, Ngoc Nhi; Murphy, William L

    2014-12-25

    Growth factors (GFs) are major regulatory proteins that can govern cell fate, migration, and organization. Numerous aspects of the cell milieu can modulate cell responses to GFs, and GF regulation is often achieved by the native extracellular matrix (ECM). For example, the ECM can sequester GFs and thereby control GF bioavailability. In addition, GFs can exert distinct effects depending on whether they are sequestered in solution, at two-dimensional interfaces, or within three-dimensional matrices. Understanding how the context of GF sequestering impacts cell function in the native ECM can instruct the design of soluble or insoluble GF sequestering moieties, which can then be used in a variety of bioengineering applications. This Feature Article provides an overview of the natural mechanisms of GF sequestering in the cell milieu, and reviews the recent bioengineering approaches that have sequestered GFs to modulate cell function. Results to date demonstrate that the cell response to GF sequestering depends on the affinity of the sequestering interaction, the spatial proximity of sequestering in relation to cells, the source of the GF (supplemented or endogenous), and the phase of the sequestering moiety (soluble or insoluble). We highlight the importance of context for the future design of biomaterials that can leverage endogenous molecules in the cell milieu and mitigate the need for supplemented factors. PMID:25182455

  17. Light and electron microscopic immunohistochemical observations of p75 nerve growth factor receptor-immunoreactive dermal nerves in prurigo nodularis

    Microsoft Academic Search

    Yong Liang; Jan A. Marcusson; Olle Johansson

    1999-01-01

    \\u000a Abstract Prurigo nodularis is an inflammatory skin disease characterized by neurohyperplasia. Neurotrophins and their receptors play\\u000a a critical role in nerve growth, differentiation, maturation and maintenance, including cutaneous nerve fiber growth and innervation.\\u000a They may also be responsible for events related to the growth and differentiation control of keratinocytes. To explore the\\u000a exact distribution of the p75 low-affinity nerve growth

  18. Human melanocytes mitigate keratinocyte-dependent contraction in an in vitro collagen contraction assay.

    PubMed

    Rakar, Jonathan; Krammer, Markus P; Kratz, Gunnar

    2015-08-01

    Scarring is an extensive problem in burn care, and treatment can be especially complicated in cases of hypertrophic scarring. Contraction is an important factor in scarring but the contribution of different cell types remains unclear. We have investigated the contractile behavior of keratinocytes, melanocytes and fibroblasts by using an in vitro collagen gel assay aimed at identifying a modulating role of melanocytes in keratinocyte-mediated contraction. Cells were seeded on a collagen type I gel substrate and the change in gel dimensions were measured over time. Hematoxylin & Eosin-staining and immunohistochemistry against pan-cytokeratin and microphthalmia-associated transcription factor showed that melanocytes integrated between keratinocytes and remained there throughout the experiments. Keratinocyte- and fibroblast-seeded gels contracted significantly over time, whereas melanocyte-seeded gels did not. Co-culture assays showed that melanocytes mitigate the keratinocyte-dependent contraction (significantly slower and 18-32% less). Fibroblasts augmented the contraction in most assays (approximately 6% more). Non-contact co-cultures showed some influence on the keratinocyte-dependent contraction. Results show that mechanisms attributable to melanocytes, but not fibroblasts, can mitigate keratinocyte contractile behavior. Contact-dependent mechanisms are stronger modulators than non-contact dependent mechanisms, but both modes carry significance to the contraction modulation of keratinocytes. Further investigations are required to determine the mechanisms involved and to determine the utility of melanocytes beyond hypopigmentation in improved clinical regimes of burn wounds and wound healing. PMID:25466959

  19. Fibroblast growth factor receptor substrate 2 participates in vascular endothelial growth factor-induced signaling

    Microsoft Academic Search

    Konstantin V. Stoletov; Kirsty E. Ratcliffe; Bruce I. Terman

    2002-01-01

    Vascular endothelial growth factor (VEGF) activates endothelial cells, in part, by interacting with the kinase insert domain-containing receptor (KDR) receptor tyrosine kinase. Although progress has been made in the identification of cell-signaling proteins that participate in the VEGF-induced response, questions remain concerning the molecular interactions that allow coupling of receptor activation with an increased cellular response. Evidence is provided in

  20. The role of vascular endothelial growth factors and fibroblast growth factors in angiogenesis during otitis media.

    PubMed

    Husseman, Jacob; Palacios, Sean D; Rivkin, Alexander Z; Oehl, Heinz; Ryan, Allen F

    2012-01-01

    The middle ear response to otitis media includes transformation and hyperplasia of the mucosal epithelium and subepithelial connective tissue. Significant neovascularization is also noted, which occurs both to support the hypertrophied mucosa and to mediate the increased trafficking of leukocytes. We investigated the role of two known potent angiogenic growth factor families, the fibroblast growth factors (FGFs) and vascular endothelial growth factors (VEGFs), in middle ear mucosal angiogenesis. DNA microarrays were used to evaluate the expression of FGFs and VEGFs, as well as their receptors and unique signaling proteins, in the middle ears of mice undergoing a complete course of acute bacterial otitis media. In addition, a member of each family was introduced to the middle ear submucosal compartment of the normal middle ears of guinea pigs, by a continuous-release osmotic minipump system over 1 week. During the course of bacterial otitis media, a significant regulation of a number of genes important for angiogenesis was identified. Histologic evaluation of middle ear mucosa following micropump infusion of both FGF1 and VEGF-A showed significant angiogenesis at the site of infusion in comparison to control saline infusion. These results support a role for FGFs and VEGFs in the neovascularization of the middle ear mucosa during otitis media, and offer a potential avenue for therapeutic intervention. PMID:22104377

  1. Oncogenic Human Papillomaviruses Activate the Tumor-Associated Lens Epithelial-Derived Growth Factor (LEDGF) Gene

    PubMed Central

    Leitz, Jenny; Reuschenbach, Miriam; Lohrey, Claudia; Honegger, Anja; Accardi, Rosita; Tommasino, Massimo; Llano, Manuel; von Knebel Doeberitz, Magnus; Hoppe-Seyler, Karin; Hoppe-Seyler, Felix

    2014-01-01

    The expression of the human papillomavirus (HPV) E6/E7 oncogenes is crucial for HPV-induced malignant cell transformation. The identification of cellular targets attacked by the HPV oncogenes is critical for our understanding of the molecular mechanisms of HPV-associated carcinogenesis and may open novel therapeutic opportunities. Here, we identify the Lens Epithelial-Derived Growth Factor (LEDGF) gene as a novel cellular target gene for the HPV oncogenes. Elevated LEDGF expression has been recently linked to human carcinogenesis and can protect tumor cells towards different forms of cellular stress. We show that intracellular LEDGF mRNA and protein levels in HPV-positive cancer cells are critically dependent on the maintenance of viral oncogene expression. Ectopic E6/E7 expression stimulates LEDGF transcription in primary keratinocytes, at least in part via activation of the LEDGF promoter. Repression of endogenous LEDGF expression by RNA interference results in an increased sensitivity of HPV-positive cancer cells towards genotoxic agents. Immunohistochemical analyses of cervical tissue specimens reveal a highly significant increase of LEDGF protein levels in HPV-positive lesions compared to histologically normal cervical epithelium. Taken together, these results indicate that the E6/E7-dependent maintenance of intracellular LEDGF expression is critical for protecting HPV-positive cancer cells against various forms of cellular stress, including DNA damage. This could support tumor cell survival and contribute to the therapeutic resistance of cervical cancers towards genotoxic treatment strategies in the clinic. PMID:24604027

  2. Slow release of ions from internalized silver nanoparticles modifies the epidermal growth factor signaling response.

    PubMed

    Comfort, Kristen K; Maurer, Elizabeth I; Hussain, Saber M

    2014-11-01

    Due to their distinctive physiochemical properties, including a robust antibacterial activity and plasmonic capability, hundreds of consumer and medical products contain colloidal silver nanoparticles (AgNPs). However, even at sub-toxic dosages, AgNPs are able to disrupt cell functionality, through a yet unknown mechanism. Moreover, internalized AgNPs have the potential to prolong this disruption, even after the removal of excess particles. In the present study, we evaluated the impact, mechanism of action, and continual effects of 50 nm AgNP exposure on epidermal growth factor (EGF) signal transduction within a human keratinocyte (HaCaT) cell line. After AgNP expose, EGF signaling was initially obstructed due to the dissolution of particles into silver ions. However, at longer durations, the internalized AgNPs increased EGF signaling activity. This latter behavior correlated to sustained HaCaT stress, believed to be maintained through the continual dissolution of internalized AgNPs. This study raises concerns that even after exposure ceases, the retained nanomaterials are capable of acting as a slow-release mechanism for metallic ions; continually stressing and modifying normal cellular functionality. PMID:25260222

  3. Hyaluronan minimizes effects of UV irradiation on human keratinocytes.

    PubMed

    Hašová, Martina; Crhák, Tomáš; Safránková, Barbora; Dvo?áková, Jana; Muthný, Tomáš; Velebný, Vladimír; Kubala, Lukáš

    2011-05-01

    Exposure to ultraviolet (UV) irradiation has detrimental effects on skin accompanied by the increased metabolism of hyaluronan (HA), a linear polysaccharide important for the normal physiological functions of skin. In this study, the modulation of human keratinocyte response to UVB irradiation by HA (970 kDa) was investigated. Immortalized human keratinocytes (HaCaT) were irradiated by a single dose of UVB and immediately treated with HA for 6 and 24 h. The irradiation induced a significant decrease in the gene expression of CD44 and toll-like receptor 2 6 h after irradiation. The expressions of other HA receptors, including toll-like receptor 4 and the receptor for HA-mediated motility, were not detected in either the control or UVB-irradiated or HA-treated HaCaT cells. UVB irradiation induced a significant decrease in the gene expression of HA synthase-2 and hyaluronidase-2 6 h after irradiation. The expressions of HA synthase-3 and hyaluronidase-3 were not significantly modulated by UV irradiation. Interestingly, HA treatment did not significantly modulate any of these effects. In contrast, HA significantly suppressed UVB-induced pro-inflammatory cytokine release including interleukin-6 and interleukin-8. Similarly, HA treatment reduced the UVB-mediated production of transforming growth factor ?1. HA treatment also significantly reduced the UV irradiation-mediated release of soluble CD44 into the media. Finally, HA partially, but significantly, suppressed the UVB-induced decrease in cell viability. Data indicate that HA had significant protective effects for HaCaT cells against UVB irradiation. PMID:21448660

  4. Vascular endothelial growth factor and ocular neovascularization.

    PubMed Central

    Miller, J. W.

    1997-01-01

    Okamoto et al have developed an extremely useful and interesting model of retinal and subretinal neovascularization. Using molecular techniques, they have developed a transgenic model driven by overexpression of VEGF, a growth factor demonstrated to play an important role in neovascularization in many ocular diseases. They have been able to demonstrate that VEGF overexpression is sufficient to cause intraretinal and subretinal neovascularization. The mouse model is relatively cheap and reliable, does not require any exogenous agent, and has many characteristics of clinical intraocular neovascularization. The new vessels develop in the outer retina and subretinal space and have a characteristic histological appearance. They leak fluorescein on angiography, demonstrating their similarity to human disease and allowing identification and grading of neovascularization in vivo. The model can be used to investigate molecular mechanisms of VEGF-dependent neovascularization, with applications beyond ocular eye disease. The model can also be used to study anti-angiogenic agents that have the potential to treat common blinding diseases such as age-related macular degeneration. Okamoto et al have made a substantial contribution to the angiogenesis field with this work, and one looks forward to future investigations. PMID:9212726

  5. Vascular Endothelial Growth Factor in Eye Disease

    PubMed Central

    Penn, J.S.; Madan, A.; Caldwell, R.B.; Bartoli, M.; Caldwell, R.W.; Hartnett, M.E.

    2012-01-01

    Collectively, angiogenic ocular conditions represent the leading cause of irreversible vision loss in developed countries. In the U.S., for example, retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration are the principal causes of blindness in the infant, working age and elderly populations, respectively. Evidence suggests that vascular endothelial growth factor (VEGF), a 40 kDa dimeric glycoprotein, promotes angiogenesis in each of these conditions, making it a highly significant therapeutic target. However, VEGF is pleiotropic, affecting a broad spectrum of endothelial, neuronal and glial behaviors, and confounding the validity of anti-VEGF strategies, particularly under chronic disease conditions. In fact, among other functions VEGF can influence cell proliferation, cell migration, proteolysis, cell survival and vessel permeability in a wide variety of biological contexts. This article will describe the roles played by VEGF in the pathogenesis of retinopathy of prematurity, diabetic retinopathy and age-related macular degeneration. The potential disadvantages of inhibiting VEGF will be discussed, as will the rationales for targeting other VEGF-related modulators of angiogenesis. PMID:18653375

  6. Role of nerve growth factor in pain.

    PubMed

    Mizumura, Kazue; Murase, Shiori

    2015-01-01

    Nerve growth factor (NGF) was first identified as a substance that is essential for the development of nociceptive primary neurons and later found to have a role in inflammatory hyperalgesia in adults. Involvement of NGF in conditions with no apparent inflammatory signs has also been demonstrated. In this review we look at the hyperalgesic effects of exogenously injected NGF into different tissues, both human and animal, with special emphasis on the time course of these effects. The roles of NGF in inflammatory and neuropathic conditions as well as cancer pain are then reviewed. The role of NGF in delayed onset muscle soreness is described in more detail than its other roles based on the authors' recent observations. Acute effects are considered to be peripherally mediated, and accordingly, sensitization of nociceptors by NGF to heat and mechanical stimulation has been reported. Changes in the conductive properties of axons have also been reported. The intracellular mechanisms so far proposed for heat sensitization are direct phosphorylation and membrane trafficking of TRPV1 by TrkA. Little investigation has been done on the mechanism of mechanical sensitization, and it is still unclear whether mechanisms similar to those for heat sensitization work in mechanical sensitization. Long-lasting sensitizing effects are mediated both by changed expression of neuropeptides and ion channels (Na channels, ASIC, TRPV1) in primary afferents and by spinal NMDA receptors. Therapeutic perspectives are briefly discussed at the end of the chapter. PMID:25846614

  7. Growth factor involvement in tension-induced skeletal muscle growth

    NASA Technical Reports Server (NTRS)

    Vandenburgh, Herman W.

    1987-01-01

    New muscle tissue culture techniques were developed to grow embryonic skeletal myofibers which are able to differentiate into more adultlike myofibers. Studies on mechanical simulation of cultured muscle cell growth will now be more directly applicable to mechanically-induced growth in adult muscle, and lead to better models for understanding muscle tissue atrophy caused by disuse in the microgravity of space.

  8. Nanosize effect on the hygroscopic growth factor of aerosol particles

    NASA Astrophysics Data System (ADS)

    Biskos, G.; Russell, L. M.; Buseck, P. R.; Martin, S. T.

    2006-04-01

    The hygroscopic growth factors of NaCl particles having dry mobility diameters of 6 to 60 nm were measured using a tandem nano-Differential Mobility Analyzer. The growth factors steadily decreased within detection limit for dry sizes below 40 nm. The decrease is quantitatively predicted by a model that includes the Kelvin effect and a size-dependent shape factor. This factor is not tuned to the data but rather is grounded in theoretical predictions from literature. Agreement in growth factors for particles generated by two independent methods (namely, vaporization-condensation and electrospray), as well as observations of prompt deliquescence, indicates the absence of significant chemical impurities.

  9. Activated extracellular signal-regulated kinases: association with epidermal growth factor receptor/transforming growth factor alpha expression in head and neck squamous carcinoma and inhibition by anti-epidermal growth factor receptor treatments.

    PubMed

    Albanell, J; Codony-Servat, J; Rojo, F; Del Campo, J M; Sauleda, S; Anido, J; Raspall, G; Giralt, J; Roselló, J; Nicholson, R I; Mendelsohn, J; Baselga, J

    2001-09-01

    The expression of the activated mitogen-activated kinases/extracellular signal-regulated kinases (ERKs) ERK1 and ERK2 was characterized in 101 humanhead and neck squamous carcinoma specimens. Activated ERK1/2were detected at different levels in the majority of these tumors, as assayed by immunostaining with an antibody specific for the dually phosphorylated and activated ERK1 and ERK2. ERK1/2 activation levels were higher in tumors with advanced regional lymph node metastasis (P = 0.048) and in relapsed tumors (P = 0.021). The expression of epidermal growth factor (EGF) receptor (P = 0.037), transforming growth factor alpha (TGF-alpha; P < 0.001), and HER2 (P = 0.066; positive trend) correlated with activation of ERK1/2. In a multivariate analysis, both TGF-alpha (P < 0.0001) and HER2 (P = 0.045) were independently correlated with ERK1/2 activation. In turn, activation of ERK1/2 was associated with a higher Ki-67 proliferative index (P = 0.002). In EGF receptor-dependent model cells (A431 and DiFi), a specific EGF receptor tyrosine kinase inhibitor ("Iressa"; ZD1839) and a chimeric anti-EGF receptor antibody ("Cetuximab"; C225) inhibited ERK 1/2 activation at concentrations that inhibited autocrine cell proliferation. In patients on treatment with C225, the activation of ERK1/2 in skin, an EGF receptor-dependent tissue, was lower compared with control skin. Parallel changes were seen in keratinocyte Ki67 proliferation indexes in skin from C225-treated patients. Taken together, these studies provide support for a role of activation of ERK1/2 in head and neck squamous carcinoma and a correlation with EGF receptor/TGF-alpha expression. The inhibition of ERK1/2 activation in vitro and in vivo by compounds targeting the EGF receptor points to the interest of ERK1/2 as potential surrogate markers of EGF-receptor signaling in clinical therapeutic studies. PMID:11522647

  10. Growth retardation in Down syndrome in relation to insulin-like growth factors and growth hormone.

    PubMed

    Annerén, G; Gustavson, K H; Sara, V R; Tuvemo, T

    1990-01-01

    Growth retardation is a cardinal characteristic of Down syndrome (DS). It is most pronounced from the age of 6 months, when growth starts to become growth hormone (GH) regulated. DS children have normal serum levels of GH. GH regulates the production of insulin-like growth factors (IGFs), which act as growth hormones. Therefore, the serum IGF pattern and the levels of their receptors were studied in fetuses with trisomy 21 and in patients with DS throughout life. Serum levels of IGF were determined by radioimmunoassays for insulin-like growth factors 1 and 2 (RIA-IGF-1 and RIA-IGF-2) showing normal serum RIA-IGF-2 levels throughout life. However, serum RIA-IGF-1 did not rise during childhood and remained at a low level throughout life. Determination of serum IGF by a radioreceptor assay (RRA-IGF), which detects both IGF-1 and IGF-2 as well as enhanced activity in the fetal circulation, showed a deficit in serum RRA-IGF in fetuses with trisomy 21, but at birth and throughout life elevated serum RRA-IGF levels. In spite of this, no differences were observed in fetal brain or liver binding sites for IGF-1, IGF-2, or insulin. Since in the RRA-IGF method IGF-1, IGF-2, and a fetal form of IGF-1 cross-react, it is possible that there is a delayed maturation with incomplete switching from production of the fetal form of IGF to production of the GH-regulated IGF-1 in DS. The deficit in IGF-1-like peptides might account for the growth retardation in DS. In order to study the effect of human growth hormone (hGH) therapy in DS, 5 growth-retarded children with DS were treated with hGH for 6 months. During this period the growth velocity doubled and the serum IGF-1 levels were restored to normal. Thus, DS children respond to hGH treatment. PMID:1963538

  11. Axonal regeneration by chronically injured supraspinal neurons can be enhanced by exposure to insulin-like growth factor, basic fibroblast growth factor or transforming growth factor beta.

    PubMed

    Houle, J D; Ye, J H; Kane, C J

    1996-01-01

    To test whether known growth factors could promote the regenerative reponse of chronically injured neurons, we exposed the injured adult rat spinal cord to insulin-like growth factor 1 (IGF-1), basic fibroblast growth factor (bFGF) or transforming growth factor beta 1 + 2 (TGF?s) 1 month after creation of a hemisection lesion. At 1 week later an autologous peripheral nerve graft was apposed to the rostral cavity wall and 1 month later Nuclear Yellow (NY) was used to retrogradely label neurons that had grown an axon into the graft. Neurons capable of axonal regeneration after a long term (5 weeks) injury were double labeled with True Blue (TB, provided at the time of hemisection lesion) and NY. Exposure to any of the three growth factors, compared to a PBS-treated control, resulted in a significant increase in the total number of regenerating supraspinal neurons, with the greatest increase after treatment with TGF?s. Treatment with TGF?s or bFGF led to a significant increase in the number of regenerating neurons in 6 out of 7 major regions (excluding the motor cortex) contributing to descending spinal pathways. Treatment with IGF-1 promoted significant regeneration only by reticular formation neurons. These results indicate that exposure to specific growth factors can enhance axonal regeneration by chronically injured neurons, thus overcoming one significant challenge to the repair of long standing structural damage to the spinal cord. © 1996 Elsevier Science Ireland Ltd. All rights reserved. PMID:21551521

  12. Molecular cloning and expression of human hepatocyte growth factor

    Microsoft Academic Search

    Toshikazu Nakamura; Tsutomu Nishizawa; Mitchio Hagiya; Tatsuya Seki; Manabu Shimonishi; Atsushi Sugimura; Kosuke Tashiro; Shin Shimizu

    1989-01-01

    HEPATOCYTE growth factor (HGF) is the most potent mitogen for mature parenchyma! hepatocytes in primary culture, and seems to be a hepatotrophic factor that acts as a trigger for liver regeneration after partial hepatectomy and liver injury. The partial purification and characterization of HGF have been reported1-4. We have demonstrated that pure HGF from rat platelets is a new growth

  13. Vascular endothelial growth factors and angiogenesis in eye disease

    Microsoft Academic Search

    A. N. Witmer; G. F. J. M. Vrensen; C. J. F Van Noorden; R. O. Schlingemann

    2003-01-01

    The vascular endothelial growth factor (VEGF) family of growth factors controls pathological angiogenesis and increased vascular permeability in important eye diseases such as diabetic retinopathy (DR) and age-related macular degeneration (AMD). The purpose of this review is to develop new insights into the cell biology of VEGFs and vascular cells in angiogenesis and vascular leakage in general, and to provide

  14. Redundancy of myostatin and growth\\/differentiation factor 11 function

    Microsoft Academic Search

    Alexandra C McPherron; Thanh V Huynh; Se-Jin Lee

    2009-01-01

    BACKGROUND: Myostatin (Mstn) and growth\\/differentiation factor 11 (Gdf11) are highly related transforming growth factor ? (TGF?) family members that play important roles in regulating embryonic development and adult tissue homeostasis. Despite their high degree of sequence identity, targeted mutations in these genes result in non-overlapping phenotypes affecting distinct biological processes. Loss of Mstn in mice causes a doubling of skeletal

  15. Growth factor engineering by degenerate homoduplex gene family recombination

    Microsoft Academic Search

    Lance P. Encell; William E. Levinson; Michael J. Crist; A. Katrina Loomis; Laura L. Licato; Joseph J. Arensdorf; Nicole Sica; Philip T. Pienkos; Daniel J. Monticello; Wayne M. Coco

    2002-01-01

    There is great interest in engineering human growth factors as potential therapeutic agonists and antagonists. We approached this goal with a synthetic DNA recombination method. We aligned a pool of “top-strand” oligonucleotides incorporating polymorphisms from mammalian genes encoding epidermal growth factor (EGF) using multiple polymorphic “scaffold” oligonucleotides. Top strands were then linked by gap filling and ligation. This approach avoided

  16. Fibroblast growth factor 19 entry into brain

    PubMed Central

    2013-01-01

    Background Fibroblast growth factor (FGF)-19, an endocrine FGF protein mainly produced by the ileum, stimulates metabolic activity and alleviates obesity. FGF19 modulates metabolism after either intravenous or intracerebroventricular injection, and its receptor FGFR4 is present in the hypothalamus. This led to the question whether blood-borne FGF19 crosses the blood-brain barrier (BBB) to exert its metabolic effects. Methods We determined the pharmacokinetics of FGF19 permeation from blood to brain in comparison with its distribution in peripheral organs. Multiple-time regression analysis after intravenous bolus injection, in-situ brain perfusion, and HPLC assays were performed. Results FGF19 was relatively stable in blood and in the brain compartment. Significant influx was seen in the presence of excess unlabeled FGF19 in blood. This coincided with a slower decline of 125I-FGF19 in blood which suggested there was decreased clearance or peripheral tissue uptake. In support of an altered pattern of peripheral processing of 125I-FGF19 by excess unlabeled FGF19, the high influx to liver was significantly attenuated, whereas the minimal renal uptake was linearly accelerated. In the present setting, we did not detect a saturable transport of FGF19 across the BBB, as the entry rate of 125I-FGF19 was not altered by excess unlabeled FGF19 or its mouse homologue FGF15 during in-situ brain perfusion. Conclusion FGF19 remained stable in the blood and brain compartments for up to 10 min. Its influx to the brain was non-linear, non-saturable, and affected by its blood concentration and distribution in peripheral organs. Liver showed a robust and specific uptake of FGF19 that could be inhibited by the presence of excess unlabeled FGF19, whereas kidney clearance was dose-dependent. PMID:24176017

  17. 20-Hydroxycholecalciferol, Product of Vitamin D3 Hydroxylation by P450scc, Decreases NF-?B Activity by Increasing I?B? Levels in Human Keratinocytes

    PubMed Central

    Janjetovic, Zorica; Zmijewski, Michal A.; Tuckey, Robert C.; DeLeon, Damon A.; Nguyen, Minh N.; Pfeffer, Lawrence M.; Slominski, Andrzej T.

    2009-01-01

    The side chain of vitamin D3 is hydroxylated in a sequential manner by cytochrome P450scc (CYP11A1) to form 20-hydroxycholecalciferol, which can induce growth arrest and differentiation of both primary and immortalized epidermal keratinocytes. Since nuclear factor-?B (NF-?B) plays a pivotal role in the regulation of cell proliferation, differentiation and apoptosis, we examined the capability of 20-hydroxycholecalciferol to modulate the activity of NF-?B, using 1,25-dihydroxycholecalciferol (calcitriol) as a positive control. 20-hydroxycholecalciferol inhibits the activation of NF?B DNA binding activity as well as NF-?B-driven reporter gene activity in keratinocytes. Also, 20-hydroxycholecalciferol induced significant increases in the mRNA and protein levels of the NF-?B inhibitor protein, I?B?, in a time dependent manner, while no changes in total NF-?B-p65 mRNA or protein levels were observed. Another measure of NF-?B activity, p65 translocation from the cytoplasm into the nucleus was also inhibited in extracts of 20-hydroxycholecalciferol treated keratinocytes. Increased I?B? was concomitantly observed in cytosolic extracts of 20-hydroxycholecalciferol treated keratinocytes, as determined by immunoblotting and immunofluorescent staining. In keratinocytes lacking vitamin D receptor (VDR), 20-hydroxycholecalciferol did not affect I?B? mRNA levels, indicating that it requires VDR for its action on NF-?B activity. Comparison of the effects of calcitrol, hormonally active form of vitamin D3, with 20-hydrocholecalciferol show that both agents have a similar potency in inhibiting NF-?B. Since NF-?B is a major transcription factor for the induction of inflammatory mediators, our findings indicate that 20-hydroxycholecalciferol may be an effective therapeutic agent for inflammatory and hyperproliferative skin diseases. PMID:19543524

  18. Extracellular matrix and growth factors in branching morphogenesis

    NASA Technical Reports Server (NTRS)

    Hardman, P.; Spooner, B. S.

    1993-01-01

    The unifying hypothesis of the NSCORT in gravitational biology postulates that the ECM and growth factors are key interrelated components of a macromolecular regulatory system. The ECM is known to be important in growth and branching morphogenesis of embryonic organs. Growth factors have been detected in the developing embryo, and often the pattern of localization is associated with areas undergoing epithelial-mesenchymal interactions. Causal relationships between these components may be of fundamental importance in control of branching morphogenesis.

  19. Human Epidermal Growth Factor: Isolation and Chemical and Biological Properties

    Microsoft Academic Search

    Stanley Cohen; Graham Carpenter

    1975-01-01

    A polypeptide hormone has been isolated from human urine, human epidermal growth factor. It was assayed by its ability to compete with 125I-labeled mouse-derived epidermal growth factor in binding to human foreskin fibroblasts. The biological effects of the human polypeptide are similar to those previously described for the mouse hormone. These include the stimulation of the growth in vitro of

  20. Importance of Transforming Growth Factor a\\/Epidermal Growth Factor Receptor Autocrine Growth Mechanism in an Ovarian Cancer Cell Line in Vivo

    Microsoft Academic Search

    Hirohisa Kurachi; Ken-ichiro Morishige; Kyoka Amemiya; Hiroshi Adachi; Kenji Hirota; Akira Miyake; Osamu Tanizawa; Yasuhiko Sakoyama

    1991-01-01

    We have elucidated the importance of a transforming growth factor (TGF) a and epidermal growth factor receptor autocrine mechanism on the growth of a human ovarian serous cystadenocarcinoma-derived cell line (SHIN-3) in vitro. In this study, westudied the biological significance of this autocrine mechanism in vivo using female athymic nude (nu\\/nu) mice. We measured the mouse plasma epidermal growth factor

  1. Factors contributing to posttraumatic growth: a proposed structural equation model.

    PubMed

    Cadell, Susan; Regehr, Cheryl; Hemsworth, David

    2003-07-01

    With the current shift to include positive outcomes of trauma, this research was designed to explore factors that allow growth to occur. Structural equation modeling was used to test a model for understanding posttraumatic growth. A sample (N = 174) of bereaved HIV/AIDS caregivers completed questionnaires. Spirituality, social support, and stressors were found to have a positive relationship with growth. Facilitation of posttraumatic growth is crucial to all helping professions. PMID:12921208

  2. Role of muscle-derived growth factors in bone formation

    PubMed Central

    Hamrick, Mark W.; McNeil, Paul L.; Patterson, Stella L.

    2013-01-01

    Muscle and bone anabolism and catabolism are tightly coupled during growth, development, and aging, yet the cellular and molecular mechanisms linking these two tissues are not well understood. Here we show that FGF-2 and IGF-1, two growth factors known to play a major role in regulating bone formation, are localized to muscle fibers along the muscle-bone interface of the mouse forelimb. Likewise, receptors for these growth factors are also abundant in periosteum adjacent to fleshy muscle attachments along the diaphysis of long bones. Growth factor levels were quantified from homogenized mouse forelimb muscles and IGF-1 was found to be the most abundant factor with FGF-2 also detected. Growth factor levels were also analyzed in conditioned medium from cultured myotubes, and IGF-1 and FGF-2 were again detected at significant levels. Mechanically wounding C2C12 myotubes increased the release of FGF-2 into conditioned medium, whereas IGF-1 was secreted at lower concentrations than FGF-2 following injury. Together these findings suggest that muscle is an important, local source of growth factors for bone tissue. Hence, the integrated growth and development of bone and muscle is likely to be regulated in part by paracrine mechanisms at the muscle-bone interface involving growth factor signaling. PMID:20190381

  3. A keratinocyte's course of life.

    PubMed

    Houben, E; De Paepe, K; Rogiers, V

    2007-01-01

    An adequate permeability barrier function of the mammalian epidermis is guaranteed by the characteristic architecture of the stratum corneum. This uppermost layer consists of a highly organized extracellular lipid compartment which is tightly joined to the corneocytes. The generation of the extracellular lipid compartment and the transformation of the keratinocytes into corneocytes are the main features of epidermal differentiation. However, equally important is the continuous renewal of the stratum corneum, which is insured by a careful balance between the replenishment of new keratinocytes from the proliferating basal layer, and the well-orchestrated loss of the most superficial cells after the so-called 'epidermal programmed cell death'. In this overview, the complete life of keratinocytes is described, from the proliferative organization to the process of desquamation. PMID:17191035

  4. Insulin-Like Growth Factor-Independent Effects of Growth Hormone on Growth Plate Chondrogenesis and Longitudinal Bone Growth.

    PubMed

    Wu, Shufang; Yang, Wei; De Luca, Francesco

    2015-07-01

    GH stimulates growth plate chondrogenesis and longitudinal bone growth directly at the growth plate. However, it is not clear yet whether these effects are entirely mediated by the local expression and action of IGF-1 and IGF-2. To determine whether GH has any IGF-independent growth-promoting effects, we generated (TamCart)Igf1r(flox/flox) mice. The systemic injection of tamoxifen in these mice postnatally resulted in the excision of the IGF-1 receptor (Igf1r) gene exclusively in the growth plate. (TamCart)Igf1r(flox/flox) tamoxifen-treated mice [knockout (KO) mice] and their Igf1r(flox/flox) control littermates (C mice) were injected for 4 weeks with GH. At the end of the 4-week period, the tibial growth and growth plate height of GH-treated KO mice were greater than those of untreated C or untreated KO mice. The systemic injection of GH increased the phosphorylation of Janus kinase 2 and signal transducer and activator of transcription 5B in the tibial growth plate of the C and KO mice. In addition, GH increased the mRNA expression of bone morphogenetic protein-2 and the mRNA expression and protein phosphorylation of nuclear factor-?B p65 in both C and KO mice. In cultured chondrocytes transfected with Igf1r small interfering RNA, the addition of GH in the culture medium significantly induced thymidine incorporation and collagen X mRNA expression. In conclusion, our findings demonstrate that GH can promote growth plate chondrogenesis and longitudinal bone growth directly at the growth plate, even when the local effects of IGF-1 and IGF-2 are prevented. Further studies are warranted to elucidate the intracellular molecular mechanisms mediating the IGF-independent, growth-promoting GH effects. PMID:25910049

  5. TERATOGENIC RESPONSES ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF)

    EPA Science Inventory

    TITLE: TERATOGENIC RESPONSES ARE MODULATED IN MICE LACKING EXPRESSION OF EPIDERMAL GROWTH FACTOR (EGF) AND TRANSFORMING GROWTH FACTOR-ALPHA (TGF). AUTHORS (ALL): Abbott, Barbara D.1; Best, Deborah S.1; Narotsky, Michael G.1. SPONSOR NAME: None INSTITUTIONS (ALL): 1. Repro Tox ...

  6. Hepatocyte Growth Factor Induces Gefitinib Resistance of Lung Adenocarcinoma with Epidermal Growth Factor Receptor-Activating Mutations

    Microsoft Academic Search

    Seiji Yano; Wei Wang; Kunio Matsumoto; Haruko Sakurama; Takahiro Nakamura; Hirokazu Ogino; Soji Kakiuchi; Masaki Hanibuchi; Yasuhiko Nishioka; Hisanori Uehara; Tetsuya Mitsudomi; Yasushi Yatabe; Toshikazu Nakamura; Saburo Sone

    Lung cancer with epidermal growth factor receptor (EGFR)- activating mutations responds favorably to the EGFR tyrosine kinase inhibitors gefitinib and erlotinib. However, 25% to 30% of patients with EGFR-activating mutations show intrinsic resistance, and the responders invariably acquire resistance to gefitinib. Here, we showed that hepatocyte growth factor (HGF), a ligand of MET oncoprotein, induces gefitinib resistance of lung adenocarcinoma

  7. Expression of vascular endothelial growth factor and basic fibroblast growth factor in extramammary Paget disease

    PubMed Central

    Xu, Xiaoyun; Shao, Ning; Qiao, Di; Wang, Zengjun; Song, Ningjing; Song, Ninghong

    2015-01-01

    Extramammary Paget’s disease (EMPD) is a special type of cancers. The etiology of the disease is still unclear. We aimed to study the expression differences of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in EMPD tissues and corresponding adjacent normal tissues. The mRNA expression was detected by RT-PCR and the protein expression was explored by immunohistochemistry. Higher immunostaining signal scores of bFGF and VEGF in EMPD tissues had been found (z = -3.827, P < 0.001, z = -3.729, P < 0.001, respectively). In addition, the mRNA expression of bFGF and VEGF was higher in EMPD tissues, which had been validated by RT-PCR (t = 5.771, P < 0.001, t = 3.304, P = 0.004, respectively). The VEGF and bFGF might be the key signaling proteins in angiogenesis of EMPD. How to block the VEGF and bFGF in EMPD and to destroy the blood supply of the tumor cells becomes the focus of our future research. PMID:26045818

  8. Oral keratinocyte responses to nickel-based dental casting alloys in vitro.

    PubMed

    Wylie, C M; Davenport, A J; Cooper, P R; Shelton, R M

    2010-09-01

    Adverse reactions of oral mucosa to nickel-based dental casting alloys are probably due to corrosion metal ion release. We exposed H400 oral keratinocytes to two Ni-based dental alloys (Matchmate and Dsign10) as well as NiCl( 2) (1-40 microg/mL Ni(2+)). Alloy derived Ni(2+) media concentrations were determined. Direct culture on both alloys resulted in inhibited growth with a greater effect observed for Dsign10 (higher ion release). Indirect exposure of cells to conditioned media from Dsign10 negatively affected cell numbers (approximately 64% of control by 6 days) and morphology while Matchmate-derived media did not. Exposure to increasing NiCl(2) negatively affected cell growth and morphology, and the Granulocyte-macrophage colony-stimulating factor (GM-CSF) transcript was significantly up-regulated in cells following direct and indirect exposure to Dsign10. NiCl(2) exposure up-regulated all cytokine transcripts at 1 day. At day 6, IL-1beta and IL-8 transcripts were suppressed while GM-CSF and IL-11 increased with Ni(2+) dose. Accumulation of Ni(2+) ions from alloys in oral tissues may affect keratinocyte viability and chronic inflammation. PMID:20008086

  9. Characteristic Cytokines Generated by Keratinocytes and Mononuclear Infiltrates in Oral Lichen Planus

    Microsoft Academic Search

    Tetsuya Yamamoto; Tokio Osaki

    1995-01-01

    Cytokine production was investigated in oral keratinocytes and tissue-infiltrated mononuclear cells (TIMC) obtained from patients with oral lichen planus (OLP). The numbers of cells producing interleukine (IL) -1?, IL-4, IL-6, granulocyte colony-stimulating factor, and tumor necrosis factor-? per 104 cells in keratinocytes from patients with OLP were determined by enzyme-linked immunospot assay. These levels were two to threefold greater than

  10. Comparison of the enzymatic and explant methods for the culture of keratinocytes isolated from human foreskin

    PubMed Central

    ORAZIZADEH, MAHMOUD; HASHEMITABAR, MAHMOUD; BAHRAMZADEH, SOMAYEH; DEHBASHI, FRESHTEH NEJAD; SAREMY, SADEGH

    2015-01-01

    Currently, culture and growth keratinocytes are important stages in achieving a reliable and reproducible skin tissue. In the present study, two different methods, enzymatic and explant methods, for keratinocytes isolation from human foreskin were compared. Foreskins were cut into 2–3 mm pieces and placed in trypsin at 4°C overnight for separation of the epidermis from the dermis. Subsequently, these samples were divided into two groups: i) Keratinocytes separated from the epidermis by trypsin and ii) by the explant method. These keratinocytes were divided into two groups: i) With no feeder layer and ii) onto a type I collagen scaffold. The cells were evaluated using immunocytochemistry and 4?,6-diamidine-2?-phenylindole dihydrochloride (DAPI) staining. In the enzymatic treatment, after 7–10 days no attached cells were found in the cell culture dishes. In the explant method, keratinocytes were separated after ~24 h, attached rapidly and formed big colonies into a collagen scaffold. In the absence of a feeder layer, small colonies were developed with rapid loss of proliferation within 2–3 days. Keratinocytes showed positive immunoreactivity for the pan-cytokeratin marker and keratinocytes' nuclei were clearly observed. This method could be applied and developed as a component of skin substitutes to treat burns and wounds and also in laboratory testing. PMID:26137227

  11. Induction of transforming growth factor beta 1 resistance by the E1A oncogene requires binding to a specific set of cellular proteins.

    PubMed Central

    Missero, C; Filvaroff, E; Dotto, G P

    1991-01-01

    Transforming growth factors beta (TGF-beta s) are potent inhibitors of epithelial cell growth in culture and might play a similar role in vivo. Several studies have suggested that acquisition of TGF-beta resistance is an important step in epithelial tumor development. Here, we show that resistance to TGF-beta 1 growth inhibition can be induced by transformation of keratinocytes with the E1A, but not the ras, oncogene. Mutational analysis revealed that these effects closely correlate with the ability of E1A proteins to bind to the retinoblastoma gene product (p105) as well as to three other cellular proteins (p60, p107, and p300). Only partial resistance to TGF-beta 1 growth inhibition was elicited by E1A mutants that bind to a subset of proteins, whereas complete resistance was induced by E1A mutants that bind to all four proteins together. Total protection against TGF-beta growth inhibition was also induced by concomitant introduction into cells of an E1A mutant binding to the p60/p105/p107 proteins and one binding to p300. In parallel with these effects, epidermal transglutaminase, a marker of keratinocyte differentiation, was induced by TGF-beta in control but not in E1A-transformed cells. TGF-beta 1 receptor levels were only partially down-modulated by an intact E1A gene and not significantly affected by the various truncated mutants. Thus, the ability of E1A to induce TGF-beta resistance depends on its ability to bind, and presumably inactivate, several cellular proteins that may be involved in transmission of the TGF-beta signal and seem to act downstream from its receptor(s). Images PMID:1673033

  12. Intestinal hormones and growth factors: Effects on the small intestine

    PubMed Central

    Drozdowski, Laurie; Thomson, Alan BR

    2009-01-01

    There are various hormones and growth factors which may modify the intestinal absorption of nutrients, and which might thereby be useful in a therapeutic setting, such as in persons with short bowel syndrome. In partI, we focus first on insulin-like growth factors, epidermal and transferring growth factors, thyroid hormones and glucocorticosteroids. Part II will detail the effects of glucagon-like peptide (GLP)-2 on intestinal absorption and adaptation, and the potential for an additive effect of GLP2 plus steroids. PMID:19152442

  13. Platelet-rich growth factor in oral and maxillofacial surgery

    PubMed Central

    Pal, Uma Shanker; Mohammad, Shadab; Singh, Rakesh K.; Das, Somdipto; Singh, Nimisha; Singh, Mayank

    2012-01-01

    Platelet-rich growth factor is an innovative regenerative therapy used to promote hard and soft tissue healing. It involves the application of autologous platelet-leukocyte-rich plasma containing growth factors and thrombin directly to the site of treatment. It is the intrinsic growth factors released by activated platelets which are concentrated in a topical gel formula. Clinically, it is an affordable treatment with potentially broad spectrum of applications in maxillofacial surgery especially in the treatment of complex or refractory wounds. The present article reviews its various applications not only in the specialization of oral and maxillofacial surgery but also in regenerative medicine. PMID:23833484

  14. Activation of Nrf2 in keratinocytes causes chloracne (MADISH)-like skin disease in mice

    PubMed Central

    Schäfer, Matthias; Willrodt, Ann-Helen; Kurinna, Svitlana; Link, Andrea S; Farwanah, Hany; Geusau, Alexandra; Gruber, Florian; Sorg, Olivier; Huebner, Aaron J; Roop, Dennis R; Sandhoff, Konrad; Saurat, Jean-Hilaire; Tschachler, Erwin; Schneider, Marlon R; Langbein, Lutz; Bloch, Wilhelm; Beer, Hans-Dietmar; Werner, Sabine

    2014-01-01

    The transcription factor Nrf2 is a key regulator of the cellular stress response, and pharmacological Nrf2 activation is a promising strategy for skin protection and cancer prevention. We show here that prolonged Nrf2 activation in keratinocytes causes sebaceous gland enlargement and seborrhea in mice due to upregulation of the growth factor epigen, which we identified as a novel Nrf2 target. This was accompanied by thickening and hyperkeratosis of hair follicle infundibula. These abnormalities caused dilatation of infundibula, hair loss, and cyst development upon aging. Upregulation of epigen, secretory leukocyte peptidase inhibitor (Slpi), and small proline-rich protein 2d (Sprr2d) in hair follicles was identified as the likely cause of infundibular acanthosis, hyperkeratosis, and cyst formation. These alterations were highly reminiscent to the phenotype of chloracne/“metabolizing acquired dioxin-induced skin hamartomas” (MADISH) patients. Indeed, SLPI, SPRR2, and epigen were strongly expressed in cysts of MADISH patients and upregulated by dioxin in human keratinocytes in an NRF2-dependent manner. These results identify novel Nrf2 activities in the pilosebaceous unit and point to a role of NRF2 in MADISH pathogenesis. PMID:24503019

  15. Investigation of human embryonic stem cell-derived keratinocytes as an in vitro research model for mechanical stress dynamic response.

    PubMed

    Cherbuin, Thibaud; Movahednia, Mohammad Mehdi; Toh, Wei Seong; Cao, Tong

    2015-06-01

    The epidermis is mainly composed of keratinocytes forming a protective barrier. It is perpetually subjected to mechanical stress and strain during development, homeostasis and disease. Perturbation of the normal strain with alteration of its biological response may lead to severe diseases such as psoriasis and epidermolysis bullosa. To date, most of the studies about skin response to mechanical stress used immortalized cell lines (i.e. HaCaT) or primary cells from donors, which suffer issues of limited physiological relevance and inter-donor variability. It is therefore necessary to develop a new human model for the study of normal skin physiology and response to mechanical stress. In this study, we investigated the use of keratinocytes derived from human embryonic stem cells (hESCs) as a reliable alternative model to HaCaT for study of the effects of mechanical tension. With comparison to HaCaT, hESC-derived keratinocytes (hESC-Kert) were exposed to up to 3 days of cyclic mechanical stress, and gene expression changes were analyzed. Dynamic expression of several key mechanical stress related-genes was studied at mRNA level using qPCR. The expression of matrix-metallopeptidase9 was studied at protein level using ELISA. The two cell types displayed similar gene expression kinetics for most of the genes including E-cadherin, catenin?1, connexin43, desmoglein1, endothelin1, integrin?6, interleukin?1, keratin1, 6, and 10, keratinocyte growth-factor-receptor and laminin?5. Unlike HaCaT, hESC-Kert displayed early gene and protein expression of matrix metallopeptidase 9 following mechanical stimulation, suggesting that these cells have remodeling capacity that resembles that of normal human skin. Our study confirmed the use of hESC-Kert as a good model for study of skin response to mechanical stress. PMID:25283762

  16. Original article Insulin-like growth factorI during growth in bulls

    E-print Network

    Paris-Sud XI, Université de

    Original article Insulin-like growth factorI during growth in bulls H. Ronge J. Blum Université de-4-1988, accepted 24-11-1988) Summary ― In 10 bulls, changes in blood plasma concentrations of insulin the growth period. An age-dependent increase was also observed for blood levels of insulin, thyroxine

  17. Autocrine Hepatocyte Growth Factor Provides a Local Mechanism for Promoting Axonal Growth

    Microsoft Academic Search

    Xiu-Ming Yang; Jean G. Toma; Shernaz X. Bamji; Daniel J. Belliveau; Judi Kohn; Morag Park; Freda D. Miller

    1998-01-01

    In this report, we describe a novel local mechanism necessary for optimal axonal growth that involves hepatocyte growth factor (HGF). Sympathetic neurons of the superior cervical ganglion coexpress bioactive HGF and its receptor, the Met tyrosine kinase, both in vivo and in vitro. Exogenous HGF selectively promotes the growth but not survival of cultured sympathetic neurons; the magnitude of this

  18. Growth factors and corneal endothelial cells: I. Stimulation of bovine corneal endothelial cell DNA synthesis by defined growth factors.

    PubMed

    Woost, P G; Jumblatt, M M; Eiferman, R A; Schultz, G S

    1992-01-01

    Peptide growth factors and other physiological growth modifiers were evaluated for their ability to stimulate DNA synthesis in early passage cultures of bovine corneal endothelial cells (BCEC). Increasing concentrations of newborn bovine serum (0.5-10%) causes a progressive increase in DNA synthesis, which approached a plateau at 10% serum. Supplementing medium with 10% serum from different lots of newborn bovine serum or fetal bovine serum stimulated significantly different levels of DNA synthesis by BCEC. Addition of epidermal growth factor (EGF) (2 nM) to medium containing 10% newborn or fetal bovine serum further increased DNA synthesis. Dose-response curves for EGF, transforming growth factor-alpha, basic fibroblast growth factor (bFGF), and insulin-like growth factor I showed that each significantly stimulated high levels of DNA synthesis (200-700% increase) compared with BCEC cultured in serum-free medium. Vaccinia growth factor, insulin, and transforming growth factor-beta each significantly stimulated lower levels of DNA synthesis (30-200% increase), whereas nerve growth factor, multiplication stimulating activity, and platelet-derived growth factor all failed to significantly stimulate DNA synthesis above the level of serum-free medium. Other physiological growth modifiers were tested for their effects on DNA synthesis of BCEC. Transferrin and low levels of 3',5'-cyclic monophosphate (cAMP) stimulated very low levels of DNA synthesis (50% increase) whereas linoleic acid, high levels of selenium, or cAMP each inhibited DNA synthesis 25-75% below the level of BCEC cultured in serum-free medium. A series of eight formulations containing various combinations of EGF, FGF, insulin, transferrin, selenium, linoleic acid, retinoic acid, cAMP, heparin, and endothelial cell growth factor were tested for their mitogenic action on BCEC cultures. A formulation containing EGF, insulin, transferrin, selenium, and linoleic acid (EGF + ITSL) stimulated the highest level of DNA synthesis of BCEC, which was approximately 25% higher than the increase stimulated by addition of 10% newborn bovine serum. The formulation consisting of EGF + ITSL was also evaluated as a supplement to corneal storage media. Addition of EGF + ITSL to three corneal storage media (McCarey-Kaufman, K-Sol, CSM) significantly stimulated increases in cell numbers of approximately 50% above the unsupplemented corneal storage media. These results demonstrate that BCEC respond selectively to different defined peptide growth factors and physiological growth modifiers, and suggest that supplementation of corneal storage media with a defined formulation (EGF + ITSL) may enhance corneal endothelial cell density. PMID:1559341

  19. DNA repair in cultured keratinocytes

    SciTech Connect

    Liu, S.C.; Parsons, S.; Hanawalt, P.C.

    1983-07-01

    Most of our understanding of DNA repair mechanisms in human cells has come from the study of these processes in cultured fibroblasts. The unique properties of keratinocytes and their pattern of terminal differentiation led us to a comparative examination of their DNA repair properties. The relative repair capabilities of the basal cells and the differentiated epidermal keratinocytes as well as possible correlations of DNA repair capacity with respect to age of the donor have been examined. In addition, since portions of human skin are chronically exposed to sunlight, the repair response to ultraviolet (UV) irradiation (254 nm) when the cells are conditioned by chronic low-level UV irradiation has been assessed. The comparative studies of DNA repair in keratinocytes from infant and aged donors have revealed no significant age-related differences for repair of UV-induced damage to DNA. Sublethal UV conditioning of cells from infant skin had no appreciable effect on either the repair or normal replication response to higher, challenge doses of UVL. However, such conditioning resulted in attenuated repair in keratinocytes from adult skin after UV doses above 25 J/m2. In addition, a surprising enhancement in replication was seen in conditioned cells from adult following challenge UV doses.

  20. Regulation of Transforming Growth Factor ?1, Platelet-Derived Growth Factor, and Basic Fibroblast Growth Factor by Silicone Gel Sheeting in Early-Stage Scarring

    PubMed Central

    Choi, Jaehoon; Lee, Eun Hee; Park, Sang Woo

    2015-01-01

    Background Hypertrophic scars and keloids are associated with abnormal levels of growth factors. Silicone gel sheets are effective in treating and preventing hypertrophic scars and keloids. There has been no report on the change in growth factors in the scar tissue following the use of silicone gel sheeting for scar prevention. A prospective controlled trial was performed to evaluate whether growth factors are altered by the application of a silicone gel sheet on a fresh surgical scar. Methods Four of seven enrolled patients completed the study. Transforming growth factor (TGF)-?1, platelet-derived growth factor (PDGF), and basic fibroblast growth factor (bFGF) were investigated immunohistochemically in biopsies taken from five scars at 4 months following surgery. Results In both the epidermis and the dermis, the expression of TGF-?1 (P=0.042 and P=0.042) and PDGF (P=0.043 and P=0.042) was significantly lower in the case of silicone gel sheet-treated scars than in the case of untreated scars. The expression of bFGF in the dermis was significantly higher in the case of silicone gel sheet-treated scars than in the case of untreated scars (P=0.042), but in the epidermis, the expression of bFGF showed no significant difference between the groups (P=0.655). Conclusions The levels of TGF-?1, PDGF, and bFGF are altered by the silicone gel sheet treatment, which might be one of the mechanisms of action in scar prevention. PMID:25606485

  1. Normal Growth and Development in the Absence of Hepatic Insulin-Like Growth Factor I

    Microsoft Academic Search

    Shoshana Yakar; Jun-Li Liu; Bethel Stannard; Andrew Butler; Domenici Accili; Brian Sauer; Derek Leroith

    1999-01-01

    The somatomedin hypothesis proposed that insulin-like growth factor I (IGF-I) was a hepatically derived circulating mediator of growth hormone and is a crucial factor for postnatal growth and development. To reassess this hypothesis, we have used the Cre\\/loxP recombination system to delete the igf1 gene exclusively in the liver. igf1 gene deletion in the liver abrogated expression of igf1 mRNA

  2. Targeting the insulin growth factor and the vascular endothelial growth factor pathways in ovarian cancer.

    PubMed

    Shao, Minghai; Hollar, Stacy; Chambliss, Daphne; Schmitt, Jordan; Emerson, Robert; Chelladurai, Bhadrani; Perkins, Susan; Ivan, Mircea; Matei, Daniela

    2012-07-01

    Antiangiogenic therapy is emerging as a highly promising strategy for the treatment of ovarian cancer, but the clinical benefits are usually transitory. The purpose of this study was to identify and target alternative angiogenic pathways that are upregulated in ovarian xenografts during treatment with bevacizumab. For this, angiogenesis-focused gene expression arrays were used to measure gene expression levels in SKOV3 and A2780 serous ovarian xenografts treated with bevacizumab or control. Reverse transcription-PCR was used for results validation. The insulin growth factor 1 (IGF-1) was found upregulated in tumor and stromal cells in the two ovarian xenograft models treated with bevacizumab. Cixutumumab was used to block IGF-1 signaling in vivo. Dual anti-VEGF and IGF blockade with bevacizumab and cixutumumab resulted in increased inhibition of tumor growth. Immunohistochemistry measured multivessel density, Akt activation, and cell proliferation, whereas terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay measured apoptosis in ovarian cancer xenografts. Bevacizumab and cixutumumab combination increased tumor cell apoptosis in vivo compared with therapy targeting either individual pathway. The combination blocked angiogenesis and cell proliferation but not more significantly than each antibody alone. In summary, IGF-1 activation represents an important mechanism of adaptive escape during anti-VEGF therapy in ovarian cancer. This study provides the rationale for designing bevacizumab-based combination regimens to enhance antitumor activity. PMID:22700681

  3. Targeting the Insulin Growth Factor and the Vascular Endothelial Growth Factor Pathways in Ovarian Cancer

    PubMed Central

    Shao, Minghai; Hollar, Stacy; Chambliss, Daphne; Schmitt, Jordan; Emerson, Robert; Chelladurai, Bhadrani; Perkins, Susan; Ivan, Mircea; Matei, Daniela

    2015-01-01

    Antiangiogenic therapy is emerging as a highly promising strategy for the treatment of ovarian cancer, but the clinical benefits are usually transitory. The purpose of this study was to identify and target alternative angiogenic pathways that are upregulated in ovarian xenografts during treatment with bevacizumab. For this, angiogenesis-focused gene expression arrays were used to measure gene expression levels in SKOV3 and A2780 serous ovarian xenografts treated with bevacizumab or control. Reverse transcription-PCR was used for results validation. The insulin growth factor 1 (IGF-1) was found upregulated in tumor and stromal cells in the two ovarian xenograft models treated with bevacizumab. Cixutumumab was used to block IGF-1 signaling in vivo. Dual anti-VEGF and IGF blockade with bevacizumab and cixutumumab resulted in increased inhibition of tumor growth. Immunohistochemistry measured multivessel density, Akt activation, and cell proliferation, whereas terminal deoxynucleotidyl transferase–mediated dUTP nick end labeling (TUNEL) assay measured apoptosis in ovarian cancer xenografts. Bevacizumab and cixutumumab combination increased tumor cell apoptosis in vivo compared with therapy targeting either individual pathway. The combination blocked angiogenesis and cell proliferation but not more significantly than each antibody alone. In summary, IGF-1 activation represents an important mechanism of adaptive escape during anti-VEGF therapy in ovarian cancer. This study provides the rationale for designing bevacizumab-based combination regimens to enhance antitumor activity. PMID:22700681

  4. Latent transforming growth factor binding protein 4 regulates transforming growth factor beta receptor stability.

    PubMed

    Su, Chi-Ting; Huang, Jenq-Wen; Chiang, Chih-Kang; Lawrence, Elizabeth C; Levine, Kara L; Dabovic, Branka; Jung, Christine; Davis, Elaine C; Madan-Khetarpal, Suneeta; Urban, Zsolt

    2015-07-15

    Mutations in the gene for the latent transforming growth factor beta binding protein 4 (LTBP4) cause autosomal recessive cutis laxa type 1C. To understand the molecular disease mechanisms of this disease, we investigated the impact of LTBP4 loss on transforming growth factor beta (TGF?) signaling. Despite elevated extracellular TGF? activity, downstream signaling molecules of the TGF? pathway, including pSMAD2 and pERK, were down-regulated in LTBP4 mutant human dermal fibroblasts. In addition, TGF? receptors 1 and 2 (TGFBR1 and TGFBR2) were reduced at the protein but not at the ribonucleic acid level. Treatment with exogenous TGF?1 led to an initially rapid increase in SMAD2 phosphorylation followed by a sustained depression of phosphorylation and receptor abundance. In mutant cells TGFBR1 was co-localized with lysosomes. Treatment with a TGFBR1 kinase inhibitor, endocytosis inhibitors or a lysosome inhibitor, normalized the levels of TGFBR1 and TGFBR2. Co-immunoprecipitation demonstrated a molecular interaction between LTBP4 and TGFBR2. Knockdown of LTBP4 reduced TGF? receptor abundance and signaling in normal cells and supplementation of recombinant LTBP4 enhanced these measures in mutant cells. In a mouse model of Ltbp4 deficiency, reduced TGF? signaling and receptor levels were normalized upon TGFBR1 kinase inhibitor treatment. Our results show that LTBP4 interacts with TGFBR2 and stabilizes TGF? receptors by preventing their endocytosis and lysosomal degradation in a ligand-dependent and receptor kinase activity-dependent manner. These findings identify LTBP4 as a key molecule required for the stability of the TGF? receptor complex, and a new mechanism by which the extracellular matrix regulates cytokine receptor signaling. PMID:25882708

  5. Experimental estimate of the diffusivity of Vascular Endothelial Growth Factor

    E-print Network

    Núñez, Daniel A

    2006-01-01

    The diffusivity of Vascular Endothelial Growth Factor (VEGF) is a number that is very important in determining the transport of VEGF. The transport of VEGF determines crucial processes such as angiogenesis and vasculogenesis. ...

  6. Epidermal growth factor receptor downregulation by small heterodimeric binding proteins

    E-print Network

    Hackel, Benjamin J.

    No single engineered protein has been shown previously to robustly downregulate epidermal growth factor receptor (EGFR), a validated cancer target. A panel of fibronectin-based domains was engineered to bind with picomolar ...

  7. The Generation of Insulin-Like Growth Factor1Sensitive Cells by Growth Hormone Action

    Microsoft Academic Search

    Kathleen M. Zezulak; Howard Green

    1986-01-01

    Insulin-like growth factor-1 (IGF-1), a mitogenic polypeptide, is usually considered the sole effector by means of which growth hormone increases tissue mass. However, growth hormone, but not IGF-1, directly promotes the differentiation of cultured preadipocytes to adipocytes. Adipocytes newly differentiated from precursor cells in response to growth hormone were shown to be much more sensitive to the mitogenic effect of

  8. Implications of vascular endothelial growth factor for postischemic neurovascular remodeling

    Microsoft Academic Search

    Dirk Matthias Hermann; Anil Zechariah

    2009-01-01

    Neurovascular remodeling has been recently recognized as a promising target for neurologic therapies. Hopes have emerged that, by stimulating vessel growth, it may be possible to stabilize brain perfusion, and at the same time promote neuronal survival, brain plasticity, and neurologic recovery. In this review, we outline the role of vascular endothelial growth factor (VEGF) in the ischemic brain, analyzing

  9. Molecular and biological properties of vascular endothelial growth factor

    Microsoft Academic Search

    Napoleone Ferrara

    1999-01-01

    Vascular endothelial growth factor (VEGF) is a fundamental regulator of normal and abnormal angiogenesis. Recent evidence indicates that VEGF is essential for embryonic vasculogenesis and angiogenesis. Furthermore, VEGF is required for the cyclical blood vessel proliferation in the female reproductive tract and for longitudinal bone growth and endochondral bone formation. Substantial experimental evidence also implicates VEGF in pathological angiogenesis. Anti-VEGF

  10. Vascular Endothelial Growth Factor is a Secreted Angiogenic Mitogen

    Microsoft Academic Search

    David W. Leung; George Cachianes; Wun-Jing Kuang; David V. Goeddel; Napoleone Ferrara

    1989-01-01

    Vascular endothelial growth factor (VEGF) was purified from media conditioned by bovine pituitary folliculostellate cells (FC). VEGF is a heparin-binding growth factor specific for vascular endothelial cells that is able to induce angiogenesis in vivo. Complementary DNA clones for bovine and human VEGF were isolated from cDNA libraries prepared from FC and HL60 leukemia cells, respectively. These cDNAs encode hydrophilic

  11. Epidermal Growth Factor System Regulates Mucin Production in Airways

    Microsoft Academic Search

    Kiyoshi Takeyama; Karim Dabbagh; Heung-Man Lee; Carlos Agusti; James A. Lausier; Iris F. Ueki; Kathleen M. Grattan; Jay A. Nadel

    1999-01-01

    Goblet-cell hyperplasia is a critical pathological feature in hypersecretory diseases of airways. However, the underlying mechanisms are unknown, and no effective therapy exists. Here we show that stimulation of epidermal growth factor receptors (EGF-R) by its ligands, EGF and transforming growth factor alpha (TGFalpha), causes MUC5AC expression in airway epithelial cells both in in vitro and in vivo. We found

  12. Connective Tissue Growth Factor and Cardiac Fibrosis after Myocardial Infarction

    Microsoft Academic Search

    Rachael G. Dean; Leanne C. Balding; Riccardo Candido; Wendy C. Burns; Zemin Cao; Stephen M. Twigg; Louise M. Burrell

    2005-01-01

    The temporal and spatial expression of transforming growth factor (TGF)-?1 and connective tissue growth factor (CTGF) was assessed in the left ventricle of a myocardial infarction (MI) model of injury with and without angiotensin-converting enzyme (ACE) inhibition. Coronary artery ligated rats were killed 1, 3, 7, 28, and 180 days after MI. TGF-?1, CTGF, and procollagen ?1(I) mRNA were localized

  13. Vascular Endothelial Growth Factor C Induces Angiogenesis in vivo

    Microsoft Academic Search

    Yihai Cao; Philip Linden; Jacob Farnebo; Renhai Cao; Anna Eriksson; Vijay Kumar; Jian-Hua Qi; Lena Claesson-Welsh; Kari Alitalo

    1998-01-01

    Vascular endothelial growth factor C (VEGF-C) recently has been described to be a relatively specific growth factor for the lymphatic vascular system. Here we report that ectopic application of recombinant VEGF-C also has potent angiogenic effects in vivo. VEGF-C is sufficiently potent to stimulate neovascularization from limbal vessels in the mouse cornea. Similar to VEGF, the angiogenic response of corneas

  14. Multilayered Inorganic Microparticles for Tunable Dual Growth Factor Delivery

    PubMed Central

    Yu, Xiaohua; Khalil, Andrew; Dang, Phuong Ngoc; Alsberg, Eben

    2014-01-01

    There is an increasing need to control the type, quantity, and timing of growth factors released during tissue healing. Sophisticated delivery systems offering the ability to deliver multiple growth factors with independently tunable kinetics are highly desirable. Here, a multilayered, mineral coated micro-particle (MCMs) platform that can serve as an adaptable dual growth factor delivery system is developed. Bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) are bound to the mineral coatings with high binding efficiencies of up to 80%. BMP-2 is firstly bound onto a 1st mineral coating layer; then VEGF is bound onto a 2nd mineral coating layer. The release of BMP-2 is sustained over a period of 50 days while the release of VEGF is a typical two-phase release with rapid release in the first 14 days and more sustained release for the following 36 days. Notably, the release behaviors of both growth factors can be independently tailored by changing the intrinsic properties of the mineral coatings. Furthermore, the release of BMP-2 can be tuned by changing the thickness of the 2nd layer. This injectable microparticle based delivery platform with tunable growth factor release has immense potential for applications in tissue engineering and regenerative medicine. PMID:25342948

  15. Effect of sericin on diabetic hippocampal growth hormone/insulin-like growth factor 1 axis.

    PubMed

    Chen, Zhihong; Yang, Songhe; He, Yaqiang; Song, Chengjun; Liu, Yongping

    2013-07-01

    Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus model was established by intraperitoneal injection of 25 mg/kg streptozotocin for 3 successive days, following which the rats were treated with sericin for 35 days. After treatment, the blood glucose levels of the diabetic rats decreased significantly, the growth hormone level in serum and its expression in the hippocampus decreased significantly, while the insulin-like growth factor-1 level in serum and insulin-like growth factor-1 and growth hormone receptor expression in the hippocampus increased significantly. The experimental findings indicate that sericin improves disorders of the growth hormone/insulin-like growth factor 1 axis to alleviate hippocampal damage in diabetic rats. PMID:25206472

  16. Effect of sericin on diabetic hippocampal growth hormone/insulin-like growth factor 1 axis

    PubMed Central

    Chen, Zhihong; Yang, Songhe; He, Yaqiang; Song, Chengjun; Liu, Yongping

    2013-01-01

    Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus model was established by intraperitoneal injection of 25 mg/kg streptozotocin for 3 successive days, following which the rats were treated with sericin for 35 days. After treatment, the blood glucose levels of the diabetic rats decreased significantly, the growth hormone level in serum and its expression in the hippocampus decreased significantly, while the insulin-like growth factor-1 level in serum and insulin-like growth factor-1 and growth hormone receptor expression in the hippocampus increased significantly. The experimental findings indicate that sericin improves disorders of the growth hormone/insulin-like growth factor 1 axis to alleviate hippocampal damage in diabetic rats. PMID:25206472

  17. Endothelin-1 is a transcriptional target of p53 in epidermal keratinocytes and regulates UV induced melanocyte homeostasis

    PubMed Central

    Hyter, Stephen; Coleman, Daniel J.; Ganguli-Indra, Gitali; Merrill, Gary F.; Ma, Steven; Yanagisawa, Masashi; Indra, Arup K.

    2013-01-01

    Summary Keratinocytes contribute to melanocyte activity by influencing their microenvironment, in part, through secretion of paracrine factors. Here we discovered that p53 directly regulates Edn1 expression in epidermal keratinocytes and controls UV-induced melanocyte homeostasis. Selective ablation of EDN1 in murine epidermis (EDN1ep?/?) does not alter melanocyte homeostasis in newborn skin but decreases dermal melanocytes in adult skin. Results showed that keratinocytic EDN1 in a non-cell autonomous manner controls melanocyte proliferation, migration, DNA damage and apoptosis after UVB irradiation. Expression of other keratinocyte derived paracrine factors did not compensate for the loss of EDN1. Topical treatment with EDN1 receptor (EDNRB) antagonist BQ788 abrogated UV induced melanocyte activation and recapitulated the phenotype seen in EDN1ep?/? mice. Altogether, present studies establish an essential role of EDN1 in epidermal keratinocytes to mediate UV induced melanocyte homeostasis in vivo. PMID:23279852

  18. Differential Effects of Transforming Growth Factor-Beta on the Synthesis of Connective Tissue Growth Factor and Vascular Endothelial Growth Factor by Peritoneal Mesothelial Cell

    Microsoft Academic Search

    Cheuk-Chun Szeto; Ka-Bik Lai; Kai-Ming Chow; Carol Yi-Ki Szeto; Teresa Yuk-Hwa Wong; Philip Kam-Tao Li

    2005-01-01

    Background: Previous studies found that transforming growth factor-? (TGF-?) plays a conflicting role in peritoneal fibrosis. We hypothesise that TGF-? acts on peritoneal mesothelial cells (PMC) via VEGF and CTGF as downstream mediators. Methods: The effect of TGF-? in primary culture of rat PMC was studied. VEGF and CTGF mRNA expression was examined by real time quantitative polymerase chain reaction

  19. Identification and Partial Purification of a Basic Fibroblast Growth Factor-Like Growth Factor Derived from Bovine Colostrum

    Microsoft Academic Search

    T. Hironaka; H. Ohishi; T. Masaki

    1997-01-01

    Bovine colostrum that had been collected up to 6 h postpartum was fractionated by ammonium sulfate precipitation, and various fractions were examined for basic fibroblast growth factor activity. Activity that stimulated cell growth was detected in the cream fraction, which was purified by isoelectric focusing and heparin affinity chromatography. Three peaks were eluted from the heparin affinity column at ap-

  20. 47 CFR 36.604 - Calculation of the rural growth factor.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Calculation of the rural growth factor. 36.604 Section 36.604... § 36.604 Calculation of the rural growth factor. (a) Until July 30, 2012, the Rural Growth Factor (RGF) is equal to...

  1. 47 CFR 36.604 - Calculation of the rural growth factor.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Calculation of the rural growth factor. 36.604 Section 36.604 Telecommunication...General § 36.604 Calculation of the rural growth factor. The Rural Growth Factor (RGF) is equal to the sum...

  2. 47 CFR 36.604 - Calculation of the rural growth factor.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Calculation of the rural growth factor. 36.604 Section 36.604... § 36.604 Calculation of the rural growth factor. (a) Until July 30, 2012, the Rural Growth Factor (RGF) is equal to...

  3. 47 CFR 36.604 - Calculation of the rural growth factor.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Calculation of the rural growth factor. 36.604 Section 36.604 Telecommunication...General § 36.604 Calculation of the rural growth factor. The Rural Growth Factor (RGF) is equal to the sum...

  4. The Effects of Insulin-Like Growth Factor-1 Gene Therapy and Cell Transplantation on Rat Acute Wound Model

    PubMed Central

    Talebpour Amiri, Fereshteh; Fadaei Fathabadi, Fatemeh; Mahmoudi Rad, Mahnaz; Piryae, Abbas; Ghasemi, Azar; Khalilian, Alireza; Yeganeh, Farshid; Mosaffa, Nariman

    2014-01-01

    Background: Wound healing is a complex process. Different types of skin cells, extracellular matrix and variety of growth factors are involved in wound healing. The use of recombinant growth factors in researches and production of skin substitutes are still a challenge. Objectives: Much research has been done on the effects of gene therapy and cell therapy on wound healing. In this experimental study, the effect of insulin-like growth factor (IGF-1) gene transfer in fibroblast cells was assessed on acute dermal wound healing. Materials and Methods: Fibroblasts were cultured and transfected with IGF-1. Lipofectamine 2000 was used as a reagent of transfection. Transgene expression levels were measured by the enzyme linked immunosorbent assay (ELISA). To study in vivo, rats (weighing 170-200 g) were randomly divided into three groups (five/group) and full-thickness wounds were created on the dorsum region. Suspensions of transfected fibroblast cells were injected into the wound and were compared with wounds treated with native fibroblast cells and normal saline. For the microscopic examination, biopsy was performed on day seven. Results: In vitro, the maximum expression of IGF1 (96.95 pg/mL) in transfected fibroblast cells was 24 hours after gene transfer. In vivo, it was clear that IGF-1 gene therapy caused an increase in the number of keratinocyte cells during the wound healing process (mean of group A vs. group B with P value = 0.01, mean of group A vs. group C with P value = 0.000). Granulation of tissue formation in the transfected fibroblast group was more organized when compared with the normal saline group and native fibroblast cells. Conclusions: This study indicated that the optimization of gene transfer increases the expression of IGF-1. High concentrations of IGF-1, in combination with cell therapy, have a significant effect on wound healing. PMID:25558384

  5. The role of vascular endothelial growth factor in pathological angiogenesis

    Microsoft Academic Search

    Napoleone Ferrara

    1995-01-01

    Vascular endothelial growth factor (VEGF) is a diffusible endothelial cell-specific mitogen and angiogenic factor that can also increase vascular permeability. By alternative splicing of mRNA, VEGF may exist as one of four different isoforms that have similar biological activities but differ markedly in targeting and bioavailability. The VEGF receptors are specifically expressed in the cell surface of vascular endothelial cells.

  6. Regulation of fibroblast growth factor-23 in chronic kidney disease

    Microsoft Academic Search

    Per-Anton Westerberg; Torbjorn Linde; Bjorn Wikstrom; Osten Ljunggren; Mats Stridsberg; Tobias E. Larsson

    2007-01-01

    Background. Fibroblast growth factor-23 (FGF23) is a circulating factor that regulates the renal reabsorption of inorganic phosphate (Pi) and is increased in chronic kidney disease (CKD). The aim of the current investigation was to study the regulation of FGF23 in CKD subjects with various degree of renal function. As such, we analysed the relationship between FGF23, Pi, calcium, parathyriod hormone

  7. Expression of Local Hepatocyte Growth Factor System in Vascular Tissues

    Microsoft Academic Search

    Y. Nakamura; R. Morishita; J. Higaki; I. Kida; M. Aoki; A. Moriguchi; K. Yamada; S. I. Hayashi; Y. Yo; K. Matsumoto; T. Nakamura; T. Ogihara

    1995-01-01

    Since endothelial cells (EC) are known to secrete various anti-proliferative and vasodilating factors, an agent that promotes seeding or regeneration of EC may have potential therapeutic value against vascular smooth muscle cell (VSMC) proliferation. For the above purpose, we have found that hepatocyte growth factor (HGF) fulfills such conditions. However, the local HGF system has not yet clarified. Therefore, we

  8. Isolation, cultivation and transfection of human keratinocytes.

    PubMed

    Zare, Sona; Zarei, Mohammad Ali; Ghadimi, Tayyeb; Fathi, Fardin; Jalili, Ali; Hakhamaneshi, Mohammad Saeed

    2014-04-01

    Human keratinocytes could be used in the repair of damaged skin, in tissue engineering applications, gene therapy and recently, the generation of iPS cells. We isolated human keratinocytes from foreskin and subsequently cultured them on fibronectin, collagen type I, gelatin and laminin-coated dishes that contained three different types of serum-free medium (epilife, KSM or CnT). We developed improved conditions for efficient transfection of these human keratinocytes by testing three common transfection methods and a GFP plasmid vector. The isolated cells showed typical keratinocyte morphology and expressed the epithelial cell specific antigen, cytokeratin 14. Collagen type 1, epilife medium and lipofectamin 2000 gave the best results for isolation and transfection of human keratinocytes. Our protocol can be used as a reproducible, simple and efficient method for isolation, cultivation and genetic manipulation of human keratinocytes, which may be useful in cell and gene therapy applications. PMID:24323435

  9. HPV16 E5 deregulates the autophagic process in human keratinocytes

    PubMed Central

    Belleudi, Francesca; Nanni, Monica; Raffa, Salvatore; Torrisi, Maria Rosaria

    2015-01-01

    Autophagy plays key roles during host defense against pathogens, but viruses have evolved strategies to block the process or to exploit it for replication and successful infection. The E5 oncoprotein of human papillomavirus type 16 (HPV16 E5) perturbs epithelial homeostasis down-regulating the expression of the keratinocyte growth factor receptor (KGFR/FGFR2b), whose signaling induces autophagy. Here we investigated the possible effects of 16E5 on autophagy in human keratinocytes expressing the viral protein. The 16E5 presence strongly inhibited the autophagic process, while forced expression and activation of KGFR counteracted this effect, demonstrating that the viral protein and the receptor exert opposite and interplaying roles not only on epithelial differentiation, but also in the control of autophagy. In W12 cells, silencing of the 16E5 gene in the context of the viral full length genome confirmed its role on autophagy inhibition. Finally, molecular approaches showed that the viral protein interferes with the transcriptional regulation of autophagy also through the impairment of p53 function, indicating that 16E5 uses parallel mechanisms for autophagy impairment. Overall our results further support the hypothesis that a transcriptional crosstalk among 16E5 and KGFR might be the crucial molecular driver of epithelial deregulation during early steps of HPV infection and transformation. PMID:25826082

  10. Growth Factor Regulation of Cell Cycle Progression in Mammary Epithelial Cells

    Microsoft Academic Search

    Malinda A. Stull; Anne M. Rowzee; Aimee V. Loladze; Teresa L. Wood

    2004-01-01

    Growth factors are among the critical positive and negative regulators of cell proliferation for normal mammary\\/breast epithelial cells and for breast cancer cells. The mechanisms by which specific growth factors regulate the cell cycle in mammary\\/breast epithelial cells is beginning to be understood for several growth factor families, including the epidermal growth factor, insulin-like growth factor, and transforming growth factor-beta

  11. Nerve Growth Factor Potentiates the Neurotoxicity of ? Amyloid

    NASA Astrophysics Data System (ADS)

    Yankner, Bruce A.; Caceres, Alfredo; Duffy, Lawrence K.

    1990-11-01

    The role of growth factors in the pathogenesis of Alzheimer disease is unknown. The ?-amyloid protein accumulates abnormally in the brain in Alzheimer disease and is neurotoxic to differentiated hippocampal neurons in culture. Nerve growth factor (NGF) increased the neurotoxic potency of a ?-amyloid polypeptide by a factor of ?100,000, which resulted in a reduction of the ?-amyloid neurotoxic EC50 from 0.1 ?M to 1 pM. This potentiating effect of NGF was reversed by a monoclonal antibody against NGF and was not observed for a variety of other neurotrophic growth factors. Exposure of hippocampal neurons to very low concentrations of ? amyloid alone resulted in a marked induction of immunoreactive NGF receptors. Addition of NGF with ? amyloid resulted in the appearance of neurodegenerative changes in NGF receptor-positive neurons. The early and profound degeneration of hippocampal and basal forebrain cholinergic neurons that occurs in Alzheimer disease may result from a neurotoxic interaction of ? amyloid with NGF.

  12. Inhibition of vascular endothelial growth factor-induced angiogenesis suppresses tumour growth in vivo

    NASA Astrophysics Data System (ADS)

    Kim, K. Jin; Li, Bing; Winer, Jane; Armanini, Mark; Gillett, Nancy; Phillips, Heidi S.; Ferrara, Napoleone

    1993-04-01

    THE development of new blood vessels (angiogenesis) is required for many physiological processes including embryogenesis, wound healing and corpus luteum formation1,2. Blood vessel neoformation is also important in the pathogenesis of many disorders1-5, particularly rapid growth and metastasis of solid tumours3-5. There are several potential mediators of tumour angiogenesis, including basic and acidic fibroblast growth factors, tumour necrosis factor-? and transforming factors-? and -? 1,2. But it is unclear whether any of these agents actually mediates angiogenesis and tumour growth in vivo. Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen and an angiogenesis inducer released by a variety of tumour cells and expressed in human tumours in situ. To test whether VEGF may be a tumour angiogenesis factor in vivo, we injected human rhabdomyosar-coma, glioblastoma multiforme or leiomyosarcoma cell lines into nude mice. We report here that treatment with a monoclonal antibody specific for VEGF inhibited the growth of the tumours, but had no effect on the growth rate of the tumour cells In vitro. The density of vessels was decreased in the antibody-treated tumours. These findings demonstrate that inhibition of the action of an angiogenic factor spontaneously produced by tumour cells may suppress tumour growth in vivo.

  13. Mammalian Transforming growth factor-bs: Smad signaling and physio-pathological roles

    E-print Network

    Paris-Sud XI, Université de

    1 Mammalian Transforming growth factor-bs: Smad signaling and physio- pathological roles Delphine receptors that activate transcription factors of the Smad family. 1. Introduction The Transforming Growth

  14. Anti-Vascular Endothelial Growth Factor Monoclonal Antibodies

    Microsoft Academic Search

    Ernest S. Han; Bradley J. Monk

    \\u000a As tumors grow and metastasize, they require the formation of new blood vessels or angiogenesis. This process is regulated\\u000a by a complex balance of pro- and antiangiogenic factors. One of these factors, vascular endothelial growth factor (VEGF),\\u000a has been extensively studied and found to be an important stimulatory signal that drives angiogenesis. VEGF belongs to a family\\u000a that consists of

  15. Activation of HER4 by heparin-binding EGF-like growth factor stimulates chemotaxis but not proliferation.

    PubMed Central

    Elenius, K; Paul, S; Allison, G; Sun, J; Klagsbrun, M

    1997-01-01

    Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a potent mitogen and chemotactic factor for fibroblasts, smooth muscle cells and keratinocytes. It is demonstrated that HB-EGF is not only a ligand for HER1, as previously reported, but for HER4 as well. HB-EGF binds to NIH 3T3 cells overexpressing either HER1 or HER4 alone, but not HER2 or HER3 alone. Binding to HER4 is independent of HER1. The ability of HB-EGF to bind to two different receptors is in contrast to EGF which binds to HER1, but not to HER4, and heregulin-beta1 which binds to HER4, but not to HER1. Besides binding, HB-EGF activates HER4. For example (i) it induces tyrosine phosphorylation of HER4 in cells overexpressing this receptor and of endogenous HER4 in MDA-MB-453 cells and astrocytes; (ii) it induces association of phosphatidylinositol 3-kinase (PI3-K) activity with HER4; and (iii) it is a potent chemotactic factor for cells overexpressing HER4. Chemotaxis is inhibited by wortmannin, a PI3-K inhibitor, suggesting a possible role for PI3-K in mediating HB-EGF-stimulated chemotaxis. On the other hand, HB-EGF is not a mitogen for cells expressing HER4, in contrast to its ability to stimulate both chemotaxis and proliferation in cells expressing HER1. It was concluded that HER4 is a newly described receptor for HB-EGF and that HB-EGF can activate two EGF receptor subtypes, HER1 and HER4, but with different biological responses. PMID:9135143

  16. Transport of biotin in human keratinocytes.

    PubMed

    Grafe, Franziska; Wohlrab, Wolfgang; Neubert, Reinhard H; Brandsch, Matthias

    2003-03-01

    Biotin is an essential micronutrient for normal cellular function, growth, and development. Biotin deficiency leads to pathologic, dermatologic, and neurocutaneous manifestations in skin and its appendages. Previous studies described the presence of specific biotin transport systems in the epithelia of the intestine, liver, kidney, and placenta, and in blood mononuclear cells. The aim of this study was to examine biotin transport into human keratinocytes. Uptake of [3H]biotin was measured both in the HaCaT cell line and in native keratinocytes in primary culture. Uptake of [3H]biotin (6 nM) in HaCaT cells was linear for up to 5 min of incubation. In the presence of an Na+ gradient total biotin uptake was 4- to 5-fold higher than in the absence of sodium ions. Biotin uptake was not altered by H+ and Cl- gradients. This transport system exhibited a Michaelis-Menten constant for biotin of 22.7+/-1.0 microM and a maximal velocity of 163.6+/-3.5 pmol per 5 min per mg protein. [3H]Biotin uptake (6 nM) was strongly inhibited by lipoic acid (oxidized form, Ki=4.6 microM; reduced form, Ki=11.4 microM), pantothenic acid (Ki=1.2 microM), and desthiobiotin (Ki=15.2 microM), but not by biocytin or biotin methyl ester. Measured at [3H]biotin concentrations of 0.1-10 nM we obtained kinetic evidence for the presence of a second transport component that is saturable at very low biotin concentrations (Kt=2.6+/-0.1 nM). Unlabeled lipoic acid and pantothenic acid (20 nM) did not inhibit the [3H]biotin uptake (1 nM). We conclude that human keratinocytes express the Na+-dependent multivitamin transporter with preference for pantothenate and a very high affinity transport component with specificity for biotin. PMID:12603856

  17. Constitution of fibrin-based niche for in vitro differentiation of adipose-derived mesenchymal stem cells to keratinocytes.

    PubMed

    Sivan, Unnikrishnan; Jayakumar, K; Krishnan, Lissy K

    2014-12-01

    Epithelialization of chronic cutaneous wound is troublesome and may require use of skin/cell substitutes. Adipose-derived mesenchymal stem cells (ADMSCs) have immense potential as autologous cell source for treating wounds; they can cross the germ layer boundary of differentiation and regenerate skin. When multipotent adult stem cells are considered for skin regeneration, lineage committed keratinocytes may be beneficial to prevent undesirable post-transplantation outcome. This study hypothesized that ADMSCs may be directed to epidermal lineage in vitro on a specifically designed biomimetic and biodegradable niche. Cells were seeded on the test niche constituted with fibrin, fibronectin, gelatin, hyaluronic acid, laminin V, platelet growth factor, and epidermal growth factor in the presence of cell-specific differentiation medium (DM). The ADMSCs grown on bare tissue culture polystyrene surface in DM is designated DM-control and those grown in basal medium (BM) is the BM-control. Lineage commitment was monitored with keratinocyte-specific markers such as cytokeratin 14, cytokeratin 5, cytokeratin 19, and integrin ?6 at the transcriptional/translational level. The in vitro designed biomimetic fibrin composite matrix may have potential application as cell transplantation vehicle. PMID:25469318

  18. Cytokine and Growth Factor Responses After Radiotherapy for Localized Ependymoma

    SciTech Connect

    Merchant, Thomas E. [Department of Radiological Sciences, St. Jude Children's Research Hospital, Memphis, TN (United States)], E-mail: thomas.merchant@stjude.org; Li Chenghong; Xiong Xiaoping [Department of Biostatistics, St. Jude Children's Research Hospital, Memphis, TN (United States); Gaber, M. Waleed [Department of Biomedical Engineering and Imaging, University of Tennessee Health Science Center, Memphis, TN (United States)

    2009-05-01

    Purpose: To determine the time course and clinical significance of cytokines and peptide growth factors in pediatric patients with ependymoma treated with postoperative radiotherapy (RT). Methods and Materials: We measured 15 cytokines and growth factors (fibroblast growth factor, epidermal growth factor, vascular endothelial growth factor [VEGF], interleukin [IL]-1{beta}, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, interferon-{gamma}, tumor necrosis factor-{alpha}, granulocyte-macrophage colony-stimulating factor, monocyte chemoattractant protein-1, and macrophage inflammatory protein-{alpha}) from 30 patients before RT and 2 and 24 h, weekly for 6 weeks, and at 3, 6, 9, and 12 months after the initiation of RT. Two longitudinal models for the trend of log-transformed measurements were fitted, one during treatment and one through 12 months. Results: During RT, log IL-8 declined at a rate of -0.10389/wk (p = 0.0068). The rate of decline was greater (p = 0.028) for patients with an infratentorial tumor location. The decline in IL-8 after RT was significant when stratified by infratentorial tumor location (p = 0.0345) and more than one surgical procedure (p = 0.0272). During RT, the decline in log VEGF was significant when stratified by the presence of a ventriculoperitoneal shunt. After RT, the log VEGF declined significantly at a rate of -0.06207/mo. The decline was significant for males (p = 0.0222), supratentorial tumors (p = 0.0158), one surgical procedure (p = 0.0222), no ventriculoperitoneal shunt (p = 0.0005), and the absence of treatment failure (p = 0.0028). Conclusion: The pro-inflammatory cytokine IL-8 declined significantly during RT and the decline differed according to tumor location. The angiogenesis factor VEGF declined significantly during the 12 months after RT. The decline was greater in males, those without a ventriculoperitoneal shunt, and in those with favorable disease factors, including one surgical procedure, supratentorial tumor location, and tumor control.

  19. Growth hormone, the insulin-like growth factor axis, insulin and cancer risk

    Microsoft Academic Search

    Indraneel Banerjee; Philip G. Murray; Andrew G. Renehan; Peter E. Clayton

    2010-01-01

    Growth hormone (GH), insulin-like growth factor (IGF)-I and insulin have potent growth-promoting and anabolic actions. Their potential involvement in tumor promotion and progression has been of concern for several decades. The evidence that GH, IGF-I and insulin can promote and contribute to cancer progression comes from various sources, including transgenic and knockout mouse models and animal and human cell lines

  20. Characterization of multipotent adult stem cells from the skin: transforming growth factor-? (TGF-?) facilitates cell growth

    Microsoft Academic Search

    Yoko Kawase; Yasuo Yanagi; Tsuyoshi Takato; Manabu Fujimoto; Hitoshi Okochi

    2004-01-01

    Recently, adult stem cells have been isolated from the skin and designated as skin-derived precursors (SKPs). These SKPs, cultured in vitro, can give rise to neurons, glia, smooth muscle cells, and adipocytes. In the current study, we confirmed the clonal expansion of SKPs using a sphere-forming culture system in a medium containing methylcellulose. Among the growth factors, only transforming growth

  1. Inhibition of vascular endothelial growth factor-induced angiogenesis suppresses tumour growth in vivo

    Microsoft Academic Search

    K. Jin Kim; Bing Li; Jane Winer; Mark Armanini; Nancy Gillett; Heidi S. Phillips; Napoleone Ferrara

    1993-01-01

    THE development of new blood vessels (angiogenesis) is required for many physiological processes including embryogenesis, wound healing and corpus luteum formation1,2. Blood vessel neoformation is also important in the pathogenesis of many disorders1-5, particularly rapid growth and metastasis of solid tumours3-5. There are several potential mediators of tumour angiogenesis, including basic and acidic fibroblast growth factors, tumour necrosis factor-alpha and

  2. Advances in pubertal growth and factors influencing it: Can we increase pubertal growth?

    PubMed Central

    Soliman, Ashraf; De Sanctis, Vincenzo; Elalaily, Rania; Bedair, Said

    2014-01-01

    Puberty is a period of development characterized by partially concurrent changes which includes growth acceleration, alteration in body composition and appearance of secondary sex characteristics. Puberty is characterized by an acceleration and then deceleration in skeletal growth. The initiation, duration and amount of growth vary considerably during the growth spurt. Pubertal growth and biological maturation are dynamic processes regulated by a variety of genetic and environmental factors. Changes in skeletal maturation and bone mineral accretion concomitant with the stage of pubertal development constitute essential components in the evaluation of growth during this pubertal period. Genetic, endocrine and nutritional factors and ethnicity contribute variably to the amount of growth gained during this important period of rapid changes. Many studies investigated the possibility of increasing pubertal growth to gain taller final adult height in adolescents with idiopathic short stature (ISS). The pattern of pubertal growth, its relation to sex maturity rating and factors affecting them has been addressed in this review. The results of different trials to increase final adult height of adolescents using different hormones have been summarized. These data enables Endocrinologists to give in-depth explanations to patients and families about the efficacy and clinical significance as well as the safety of using these therapies in the treatment of adolescents with ISS. PMID:25538878

  3. A high yield method for growing primary canine keratinocytes.

    PubMed

    Watson, Adrian; Baker, Claire; Bailey, Julie; Fray, Tim; Markwell, Peter

    2004-07-01

    From a small amount of starting material, a large quantity of canine keratinocytes can be generated for experimental purposes using a refined method of explant culture to initiate the growth of basal cells with a high proliferative potential. The dividing capacity of cultures was promoted by a system selecting clonogenic cells onto an i3T3 feeder layer in combination with carefully monitoring cell morphology and passaging to select out excessive numbers of differentiated keratinocytes. Levels of contaminating dermal fibroblasts, which if left unchecked will overgrow keratinocytes, were kept to a minimum by a combination of careful explant micro-dissection to remove dermis, eliminating explants with signs of fibroblast growth as well as using cholera toxin, EGF and i3T3 feeder layers. The advantage of the method described is that it does not rely on the provision of large quantities of starting material thereby reducing the need for repeated tissue sampling, and passage numbers of five or six can be routinely achieved. This technique can therefore be useful to experimenters who require a regular and reliable source of cells for their studies. PMID:15158212

  4. Local application of growth factors (insulin-like growth factor-1 and transforming growth factor-?1) from a biodegradable poly( d,l-lactide) coating of osteosynthetic implants accelerates fracture healing in rats

    Microsoft Academic Search

    G Schmidmaier; B Wildemann; H Bail; M Lucke; T Fuchs; A Stemberger; A Flyvbjerg; N. P Haas; M Raschke

    2001-01-01

    In vitro and in vivo studies have demonstrated an osteoinductive effect of growth factors such as insulin-like growth factor-1 (IGF-1) and transforming growth factor-?1 (TGF-?1). However, for therapeutic use in fracture treatment, questions remain with regard to the local application of these proteins. A controlled, local release of growth factors from a biodegradable polylactide coating of osteosynthetic implants may have

  5. The Retinoid-Related Orphan Receptor ROR? Promotes Keratinocyte Differentiation via FOXN1

    PubMed Central

    Dai, Jun; Brooks, Yang; Lefort, Karine; Getsios, Spiro; Dotto, G. Paolo

    2013-01-01

    ROR? is a retinoid-related orphan nuclear receptor that regulates inflammation, lipid metabolism, and cellular differentiation of several non-epithelial tissues. In spite of its high expression in skin epithelium, its functions in this tissue remain unclear. Using gain- and loss-of-function approaches to alter ROR? gene expression in human keratinocytes (HKCs), we have found that this transcription factor functions as a regulator of epidermal differentiation. Among the 4 ROR? isoforms, ROR?4 is prominently expressed by keratinocytes in a manner that increases with differentiation. In contrast, ROR? levels are significantly lower in skin squamous cell carcinoma tumors (SCCs) and cell lines. Increasing the levels of ROR?4 in HKCs enhanced the expression of structural proteins associated with early and late differentiation, as well as genes involved in lipid barrier formation. Gene silencing of ROR? impaired the ability of keratinocytes to differentiate in an in vivo epidermal cyst model. The pro-differentiation function of ROR? is mediated at least in part by FOXN1, a well-known pro-differentiation transcription factor that we establish as a novel direct target of ROR? in keratinocytes. Our results point to ROR? as a novel node in the keratinocyte differentiation network and further suggest that the identification of ROR? ligands may prove useful for treating skin disorders that are associated with abnormal keratinocyte differentiation, including cancer. PMID:23922987

  6. Exercise and Circulating Insulin-Like Growth Factor I

    Microsoft Academic Search

    Ulrika Berg; Peter Bang

    2004-01-01

    Determinations of serum concentrations of total insulin-like growth factor I (tIGF-I) are important in the diagnosis, monitoring of treatment and safety evaluation of patients with growth disorders and\\/or metabolic disease. It is well established that tIGF-I status varies over time. Changes in tIGF-I levels in relation to an acute bout of exercise or repeated bouts, known as training, are likely

  7. Importin ?–Mediated Nuclear Import of Fibroblast Growth Factor Receptor

    PubMed Central

    Reilly, John F.; Maher, Pamela A.

    2001-01-01

    Although growth factor receptors are generally thought to carry out their role in signal transduction at the cell surface, many of these transmembrane proteins translocate to the nucleus after ligand stimulation. Here, we show that the nuclear translocation of fibroblast growth factor receptor (FGFR)1 occurs via a mechanism distinct from classical nuclear import but dependent on importin ?, a component of multiple nuclear import pathways. Furthermore, we show that nuclear FGFR1 induces c-Jun and is involved in the regulation of cell proliferation. These data are the first description of a nuclear import pathway for transmembrane growth factor receptors and elucidate a novel signal transduction pathway from the cell surface to the nucleus. PMID:11257130

  8. Epidermal growth factor, from gene organization to bedside

    PubMed Central

    Zeng, Fenghua; Harris, Raymond C.

    2014-01-01

    In 1962, epidermal growth factor (EGF) was discovered by Dr. Stanley Cohen while studying nerve growth factor (NGF). It was soon recognized that EGF is the prototypical member of a family of peptide growth factors that activate the EGF receptors, and that the EGF/EGF receptor signaling pathway plays important roles in proliferation, differentiation and migration of a variety of cell types, especially in epithelial cells. After the basic characterization of EGF function in the first decade or so after its discovery, the studies related to EGF and its signaling pathway have extended to a broad range of investigations concerning its biological and pathophysiological roles in development and in human diseases. In this review, we briefly describe the gene organization and tissue distribution of EGF, with emphasis on its biological and pathological roles in human diseases. PMID:24513230

  9. Urinary transforming growth factors in neoplasia: separation of /sup 125/I-labeled transforming growth factor-alpha from epidermal growth factor in human urine

    SciTech Connect

    Stromberg, K.; Hudgins, W.R.

    1986-11-01

    Purified human epidermal growth factor (hEGF) from urine promotes anchorage-independent cell growth in soft agar medium. This growth is enhanced by transforming growth factor-beta (TGF-beta), and is specifically inhibited by hEGF antiserum. Transforming growth factors of the alpha type (TGF-alpha), potentially present in normal human urine or urine from tumor-bearing patients, also promote anchorage-independent cell growth and compete with EGF for membrane receptor binding. Consequently, TGF-alpha cannot be distinguished from urinary hEGF by these two functional assays. Therefore, a technique for separation of TGF-alpha and related peptides from urinary EGF based on biochemical characteristics would be useful. Radioiodination of characterized growth factors (mouse EGF (mEGF), hEGF, and rat TGF-alpha (rTGF-alpha)), which were then separately added to human urine, was used to evaluate a resolution scheme that separates TGF-alpha from the high level of background hEGF present in human urine. Methyl bonded microparticulate silica efficiently adsorbed the /sup 125/I-labeled mEGF, /sup 125/I-labeled hEGF, and /sup 125/I-labeled rTGF-alpha that were added to 24-h human urine samples. Fractional elution with acetonitrile (MeCN) of the adsorbed silica released approximately 70 to 80% of the /sup 125/I-labeled mEGF and /sup 125/I-labeled hEGF between 25 and 30% MeCN, and over 80% of the /sup 125/I-labeled rTGF-alpha between 15 and 25% MeCN, with retention after dialysis of less than 0.2 and 1.7% of the original urinary protein, respectively. A single-step enrichment of about 400-fold for mEGF and hEGF, and 50-fold for rTGF-alpha were achieved rapidly. /sup 125/I-labeled mEGF and /sup 125/I-labeled hEGF eluted later than would be predicted on the basis of their reported molecular weight of approximately 6000, whereas /sup 125/I-labeled rTGF-alpha eluted from Bio-Gel P-10 at an approximate molecular weight of 8000 to 9000.

  10. Signaling By Fibroblast Growth Factors: The Inside Story

    NSDL National Science Digital Library

    Mitchell Goldfarb (Mount Sinai School of Medicine; Department of Biochemistry and Molecular Biology REV)

    2001-10-30

    Polypeptide growth factors bind to the extracellular domains of cell surface receptors, triggering activation of receptor-intrinsic or receptor-associated protein kinases. Although this central thesis is widely accepted, one family of proteins, the fibroblast growth factors (FGFs), have for more than a decade attracted a research "counterculture" looking for direct FGF actions inside cells. Goldfarb discusses how the search for alternative signaling pathways is moving mainstream with the help of two recent publications reporting specific intracellular targets for FGF and FGF-like proteins.

  11. Transcription factor control of growth rate dependent genes in Saccharomyces cerevisiae: A three factor design

    PubMed Central

    Fazio, Alessandro; Jewett, Michael C; Daran-Lapujade, Pascale; Mustacchi, Roberta; Usaite, Renata; Pronk, Jack T; Workman, Christopher T; Nielsen, Jens

    2008-01-01

    Background Characterization of cellular growth is central to understanding living systems. Here, we applied a three-factor design to study the relationship between specific growth rate and genome-wide gene expression in 36 steady-state chemostat cultures of Saccharomyces cerevisiae. The three factors we considered were specific growth rate, nutrient limitation, and oxygen availability. Results We identified 268 growth rate dependent genes, independent of nutrient limitation and oxygen availability. The transcriptional response was used to identify key areas in metabolism around which mRNA expression changes are significantly associated. Among key metabolic pathways, this analysis revealed de novo synthesis of pyrimidine ribonucleotides and ATP producing and consuming reactions at fast cellular growth. By scoring the significance of overlap between growth rate dependent genes and known transcription factor target sets, transcription factors that coordinate balanced growth were also identified. Our analysis shows that Fhl1, Rap1, and Sfp1, regulating protein biosynthesis, have significantly enriched target sets for genes up-regulated with increasing growth rate. Cell cycle regulators, such as Ace2 and Swi6, and stress response regulators, such as Yap1, were also shown to have significantly enriched target sets. Conclusion Our work, which is the first genome-wide gene expression study to investigate specific growth rate and consider the impact of oxygen availability, provides a more conservative estimate of growth rate dependent genes than previously reported. We also provide a global view of how a small set of transcription factors, 13 in total, contribute to control of cellular growth rate. We anticipate that multi-factorial designs will play an increasing role in elucidating cellular regulation. PMID:18638364

  12. Connective tissue growth factor (CCN2) in blood vessels.

    PubMed

    Ponticos, Markella

    2013-03-01

    The CCN family comprise the products of six immediate-early response genes (Cyr61, Ctgf, Nov and Wisp1-3) and are multi-functional proteins, characterised by four discrete protein modules in which reside functional domains: an insulin-like growth factor binding protein-like module (IGFBP) but has low affinity for IGFBPs, a von Willebrand factor type C repeat module (VWC) which mediates integrin and growth factor binding, a thrombospondin type-1 repeat module (TSP-1), and a cysteine-knot-containing module (CT). These modules mediate a host of interactions such as growth factor binding, integrin recognition, and interaction(s) with heparin and proteoglycans (reviewed in Holbourn et al., 2008; Chen and Lau, 2009). The CCN family are involved in many normal and pathological cellular processes and have a plethora of functions including cell proliferation, angiogenesis, wound healing, and fibrogenesis, tumourigenesis. In addition, many roles have been described for CCN family members in the cardiovascular system (Table 1). The focus of this review is the role of connective tissue growth factor (CCN2, CTGF) in blood vessels and in vascular pathology. PMID:23380714

  13. Targeted Overexpression of Insulin-Like Growth Factor I to Osteoblasts of Transgenic Mice: Increased

    E-print Network

    Pike, J. Wesley

    intrauterine growth, whereas IGF-I is critical for both prenatal and postnatal growth and is the dominant IGFTargeted Overexpression of Insulin-Like Growth Factor I to Osteoblasts of Transgenic Mice-like growth factor I (IGF-I) is an important growth factor for bone, yet the mechanisms that mediate its

  14. The vascular endothelial growth factor (VEGF) family: angiogenic factors in health and disease

    Microsoft Academic Search

    David IR Holmes; Ian Zachary

    2005-01-01

    SUMMARY: Vascular endothelial growth factors (VEGFs) are a family of secreted polypeptides with a highly conserved receptor-binding cystine-knot structure similar to that of the platelet-derived growth factors. VEGF-A, the founding member of the family, is highly conserved between animals as evolutionarily distant as fish and mammals. In vertebrates, VEGFs act through a family of cognate receptor kinases in endothelial cells

  15. Effect of Growth Factors on Cell Proliferation and Epithelialization in Human Skin

    Microsoft Academic Search

    F. Y. Bhora; B. J. Dunkin; S. Batzri; H. M. Aly; B. L. Bass; A. N. Sidawy; J. W. Harmon

    1995-01-01

    The failure of chronic wounds to heal remains a major medical problem. Recent studies have suggested an important role for growth factors in promoting wound healing. We investigated the mitogenic effect of basic fibroblast growth factor (FGF), insulin-like growth factor-1 (IGF-1), and epidermal growth factor (EGF), comparing their effects with those of media alone (MEM) in a human skin explant

  16. Original article Effects of gas atmosphere, platelet-derived growth factor

    E-print Network

    Boyer, Edmond

    Original article Effects of gas atmosphere, platelet-derived growth factor and leukemia inhibitory is not equivalent to in vivo growth. Platelet-derived growth factor (PDGF), mouse (mLIF) or human (hLIF) leukemia

  17. Fibronectin and alpha5 integrin regulate keratinocyte cell cycling. A mechanism for increased fibronectin potentiation of T cell lymphokine-driven keratinocyte hyperproliferation in psoriasis.

    PubMed Central

    Bata-Csorgo, Z; Cooper, K D; Ting, K M; Voorhees, J J; Hammerberg, C

    1998-01-01

    In addition to being T lymphocyte-driven, psoriasis may be due in part to abnormal integrin expression. Normal-appearing (uninvolved) skin from psoriatic patients was examined to determine whether altered fibronectin or its receptor expression is detectable before development of psoriatic lesions. In contrast to skin from normal subjects, we detect by immunofluorescence the abnormal presence of plasma fibronectin in the basal cell layer of the epidermis of psoriatic uninvolved skin. Furthermore, increased fibronectin exposure superinduces the in vitro cell cycle induction and expansion of psoriatic nonlesional keratinocytes in response to a cocktail of T cell lymphokines. Fibronectin alone also appeared to increase cell cycle entry among uninvolved but not normal keratinocytes. Concordantly, the alpha5 integrin fibronectin receptor, but not alpha2 or alpha3, is overexpressed in the in vivo nonlesional psoriatic epidermis. The involvement of alpha5beta1 in the early outgrowth of clonogenic keratinocytes in the ex vivo culture was demonstrated by the ability of anti-alpha5 mAb to inhibit keratinocyte growth on fibronectin. Thus, the fibronectin receptor appears to be one of the components required for the development of the hyperresponsiveness of psoriatic keratinocytes to signals for proliferation provided by lymphokines produced by intralesional T lymphocytes in psoriasis. PMID:9525994

  18. Therapeutic potential of growth factors and their antagonists.

    PubMed Central

    Garner, A.

    1992-01-01

    This article describes studies with four peptides, epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha), gastrin-releasing peptide/bombesin (GRP), and gastrin. The mitogenic and anti-secretory activities of EGF/TGF alpha appear to be mediated by a single class of high-affinity membrane receptors but may involve different signal transducing mechanisms. Biological activity of EGF resides in the N-terminal 42 amino acid fragment with the C-terminal undecapeptide determining binding affinity. A parenteral depot formulation of an EGF-related peptide or a small molecule agonist of the EGF receptor could have utility in treating various ulcerative disorders of the gut. Although antagonism of EGF (and thus TGF alpha) receptors and/or transducing mechanisms is frequently cited as a potential therapeutic approach to hyperproliferative diseases, blocking the action of TGF alpha, GRP, or gastrin with neutralizing antibodies or receptor antagonists did not influence the growth of a wide range of solid tumors in nude mice. These findings suggest that, unless tumor growth displays absolute dependency on one particular mitogen, antagonism of a specific growth factor is unlikely to have great effect in cancer therapy. PMID:1341074

  19. Myeloid Differentiation Factor 88 Regulates Basal and UV-Induced Expressions of IL6 and MMP-1 in Human Epidermal Keratinocytes

    Microsoft Academic Search

    Youngae Lee; Hyunjung Kim; Sangmin Kim; Mi Hee Shin; Yeon Kyung Kim; Kyu Han Kim; Jin Ho Chung

    2009-01-01

    Myeloid differentiation factor 88 (MyD88) is known as an adaptor protein for the Toll-like receptor (TLR) family and participates in signal transduction by binding to the cytoplasmic Toll\\/IL-1 receptor (TIR) domains of activated TLR. In this study, we demonstrated that expression of MyD88 is increased in photoaged skin compared with intrinsic aged human skin of the same elderly individuals, and

  20. Regeneration in Spinal Neurons: Proteosynthesis Following Nerve Growth Factor Administration

    Microsoft Academic Search

    Donald Scott Jr.; Ernest Gutmann; Peter Horsky

    1966-01-01

    Incorporation of H3-leucine into dorsal root ganglion cells in rats was markedly increased over that of controls following section of sciatic and femoral nerves. Crush lesion of dorsal roots did not increase the H3-leucine uptake of these cells except in animals which had received nerve growth factor after the operation.

  1. REVIEW ARTICLE Fibroblast growth factor signaling in mammalian tooth

    E-print Network

    Klein, Ophir

    and odontoblasts, as well as in the development and homeostasis of the stem cell niche that fuels the continuously. Keywords Fibroblast growth factors Á Tooth development Á Adult stem cells Á Mouse Á Human Introduction by somatic stem cells that reside in the proximal portion of the incisor and give rise to the differentiated

  2. A micro sustained release system for epidermal growth factor

    Microsoft Academic Search

    Joanne B. Murray; Larry Brown; Robert S. Langer; Michael Klagsburn

    1983-01-01

    Summary A technique for ensuring the controlled release of microgram and smaller amounts of biologically active epidermal growth factor (EGF) from polymeric delivery systems is described. We show that albumin in milligram quantities can facilitate the sustained release of picogram amounts of EGF for at least 3 wk. The EGF-containing polymer matrix can be placed directly into cell culture and

  3. Epidermal growth factor receptor family in lung cancer and premalignancy

    Microsoft Academic Search

    Wilbur A Franklin; Robert Veve; Fred R Hirsch; Barbara A Helfrich; Paul A Bunn

    2002-01-01

    Lung cancer, like many other epithelial malignancies, is thought to be the outcome of genetic and epigenetic changes that result in a constellation of phenotypic abnormalities in bronchial epithelium. These include morphologic epithelial dysplasia, angiogenesis, increased proliferative rate, and changes in expression of cell surface proteins, particularly overexpression of epidermal growth factor receptor (EGFR) family proteins. The EFGR family is

  4. Nerve growth factor alleviates a painful peripheral neuropathy in rats

    Microsoft Academic Search

    K. Ren; D. A. Thomas; R. Dubner

    1995-01-01

    Nerve growth factor (NGF) reverses some effects of axotomy and prevents toxic neuropathy in adult rodents. We tested the effect of NGF on behavioral hyperalgesia resulting from a chronic constriction injury (CCI) of the sciatic nerve in the rat [5]. CCI rats exhibit thermal hyperalgesia as demonstrated by a reduction of paw withdrawal latency to a noxious thermal stimulus applied

  5. Vascular Endothelial Growth Factor Induces Endothelial Fenestrations In Vitro

    Microsoft Academic Search

    Sybille Esser; Karen Wolburg; Hartwig Wolburg; Georg Breier; Teymuras Kurzchalia; Werner Risau

    1998-01-01

    Vascular endothelial growth factor (VEGF) is an important regulator of vasculogenesis, angiogene- sis, and vascular permeability. In contrast to its tran- sient expression during the formation of new blood ves- sels, VEGF and its receptors are continuously and highly expressed in some adult tissues, such as the kid- ney glomerulus and choroid plexus. This suggests that VEGF produced by the

  6. Vascular endothelial growth factor (VEGF) and its receptors

    Microsoft Academic Search

    GERA NEUFELD; TZAFRA COHEN; STELA GENGRINOVITCH; ZOYA POLTORAK

    1999-01-01

    Vascular endothelial growth factor (VEGF) is a highly specific mitogen for vascular en- dothelial cells. Five VEGF isoforms are generated as a result of alternative splicing from a single VEGF gene. These isoforms differ in their molecular mass and in biological properties such as their ability to bind to cell-surface heparan-sulfate proteoglycans. The expression of VEGF is potentiated in response

  7. Total Chemical Synthesis of Biologically Active Vascular Endothelial Growth Factor

    SciTech Connect

    Mandal, Kalyaneswar; Kent, Stephen B.H. (UC)

    2011-09-15

    The 204-residue covalent-dimer vascular endothelial growth factor (VEGF, see picture) with full mitogenic activity was prepared from three unprotected peptide segments by one-pot native chemical ligations. The covalent structure of the synthetic VEGF was confirmed by precise mass measurement, and the three-dimensional structure of the synthetic protein was determined by high-resolution X-ray crystallography.

  8. Vascular endothelial growth factor - basic science and its clinical implications

    Microsoft Academic Search

    Peter Celec; Yoshikazu Yonemitsu

    2004-01-01

    Vascular endothelial growth factor (VEGF) is the most important signaling molecule involved in the regulation of the formation of new vessels. Results of recent studies have provided new insights into the molecular mechanisms of the VEGF signaling pathways. VEGF local or systemic application represents a new approach in the therapy of ischemic diseases, especially of the coronary artery disease. Inhibition

  9. Transforming growth factor-? in breast cancer: too much, too late

    Microsoft Academic Search

    Mary Helen Barcellos-Hoff; Rosemary J Akhurst

    2009-01-01

    The contribution of transforming growth factor (TGF)? to breast cancer has been studied from a myriad perspectives since seminal studies more than two decades ago. Although the action of TGF? as a canonical tumor suppressor in breast is without a doubt, there is compelling evidence that TGF? is frequently subverted in a malignant plexus that drives breast cancer. New knowledge

  10. Preferential tendon stem cell response to growth factor supplementation.

    PubMed

    Holladay, Carolyn; Abbah, Sunny-Akogwu; O'Dowd, Colm; Pandit, Abhay; Zeugolis, Dimitrios I

    2014-01-29

    Tendon injuries are increasingly prevalent around the world, accounting for more than 100 000 new clinical cases/year in the USA alone. Cell-based therapies have been proposed as a therapeutic strategy, with recent data advocating the use of tendon stem cells (TSCs) as a potential cell source with clinical relevance for tendon regeneration. However, their in vitro expansion is problematic, as they lose their multipotency and change their protein expression profile in culture. Herein, we ventured to assess the influence of insulin-like growth factor 1 (IGF-1), growth and differentiation factor-5 (GDF-5) and transforming growth factor-?1 (TGF?1) supplementation in TSC culture. IGF-1 preserved multipotency for up to 28?days. Upregulation of decorin and scleraxis expression was observed as compared to freshly isolated cells. GDF-5 treated cells exhibited reduced differentiation along adipogenic and chondrogenic pathways after 28?days, and decorin, scleraxis and collagen type I expression was increased. After 28?days, TGF?1 supplementation led to increased scleraxis, osteonectin and collagen type II expression. The varied responses to each growth factor may reflect their role in tendon repair, suggesting that: GDF-5 promotes the transition of tendon stem cells towards tenocytes; TGF?1 induces differentiation along several pathways, including a phenotype indicative of fibrocartilage or calcified tendon, common problems in tendon healing; and IGF-1 promotes proliferation and maintenance of TSC phenotypes, thereby creating a population sufficient to have a beneficial effect. Copyright © 2014 John Wiley & Sons, Ltd. PMID:24474722

  11. Genealogy, expression, and cellular function of transforming growth factor-?

    Microsoft Academic Search

    R. Govinden; K. D. Bhoola

    2003-01-01

    The transforming growth factor-? (TGF-?) gene superfamily expresses a large set of structurally and functionally related polypeptides. Three TGF-? isoforms are regulated by specific genes and have been identified in mammals (TGF-?1, -?2, and -?3). All three-protein isoforms are observed abundantly during development and display overlapping and distinct spatial and temporal patterns of expressions. Each isoform plays a distinct role,

  12. Vascular endothelial growth factor inhibition in uveitis: a systematic review

    Microsoft Academic Search

    Nishi Gulati; Farzin Forooghian; Ronni Lieberman; Douglas A Jabs

    2010-01-01

    Vascular endothelial growth factor (VEGF) plays an important role in the pathogenesis of uveitic complications such as cystoid macular oedema (CMO), choroidal neovasularisation (CNV) and retinal neovascularisation (RNV). The use of intravitreal anti-VEGF therapies, namely bevacizumab and ranibizumab, has recently been described in the treatment of these complications. Evidence describing the use of intravitreal anti-VEGF therapy for these complications consists

  13. Epidermal growth factor receptor mutations in lung cancer

    Microsoft Academic Search

    Sreenath V. Sharma; Daphne W. Bell; Jeffrey Settleman; Daniel A. Haber

    2007-01-01

    The development and clinical application of inhibitors that target the epidermal growth factor receptor (EGFR) provide important insights for new lung cancer therapies, as well as for the broader field of targeted cancer therapies. We review the results of genetic, biochemical and clinical studies focused on somatic mutations of EGFR that are associated with the phenomenon of oncogene addiction, describing

  14. Collagens in the liver extracellular matrix bind hepatocyte growth factor

    Microsoft Academic Search

    Detlef Schuppan; Monika Schmid; Rajan Somasundaram; Renate Ackermann; Martin Ruehl; Toshikazu Nakamura

    1998-01-01

    Background & Aims: Hepatocyte growth factor (HGF), a potent mitogen for hepatocytes, binds to heparan sulfate. Because immunoreactive HGF can be detected in the interstitial extracellular matrix (ECM), where little heparan sulfate is found, the aim of this study was to investigate binding of HGF to several collagens and noncollagenous ECM proteins in vitro. Methods:125I-labeled HGF was incubated with collagens

  15. Platelet-derived growth factor in chemotactic for fibroblasts

    Microsoft Academic Search

    HEIKKI SEPPA; GARY GROTENDORST; SILJA SEPPA; ELLIOTT SCHIFFMANN; GEORGE R. MARTIN

    1982-01-01

    Chemotaxis assays in modified Boyden chambers were used to detect fibroblast chemoat- tractants in materials released from early-stage inflammatory cells, namely, mast cells, platelets, and neutrophils . Strong attractant activity was found in substances released from platelets . This activity was accounted for mainly by the platelet-derived growth factor (PDGF), which is released from the platelets and which was active

  16. Polymeric Growth Factor Delivery Strategies for Tissue Engineering

    Microsoft Academic Search

    Ruth R. Chen; David J. Mooney

    2003-01-01

    Purpose. Tissue engineering seeks to replace and regrow damaged or diseased tissues and organs from either cells resident in the surrounding tissue or cells transplanted to the tissue site. The purpose of this review is to present the application of polymeric delivery systems for growth factor delivery in tissue engineering.

  17. Basic Fibroblast Growth Factor Induces Angiogenesis in vitro

    Microsoft Academic Search

    R. Montesano; J.-D. Vassalli; A. Baird; R. Guillemin; L. Orci

    1986-01-01

    Fibroblast growth factors (FGFs) are potent mitogens for vascular and capillary endothelial cells in vitro and can stimulate the formation of blood capillaries (angiogenesis) in vivo. A crucial event in this process is the invasion of the perivascular extracellular matrix by sprouting endothelial cells. Using a recently developed in vitro model of angiogenesis, we show here that highly purified basic

  18. Characterization and estrogen regulation of uterine growth factor activity

    SciTech Connect

    Beck, C.A.

    1988-01-01

    Acid extracts of rat, bovine and rabbit uterus stimulated glucose transport, measured by phosphorylation of 2-deoxyglucose and DNA synthesis, measured by {sup 3}H-thymidne incorporation, in uterine tumor cells and in primary cultures of rat uterine cells. The stimulation of glucose transport was of the same magnitude and followed the same time course as estradiol stimulation in vivo. Uteri from estradiol-treated rat uteri contained 4 times more glucose transport-stimulating activity as control uteri. DNA synthetic activity in rat uterine homogenates was elevated 3-fold within 18-24 h after estradiol injection. Gel filtration showed molecular weight heterogeneity with activity eluting between 10-30 kDA. Both activities were acid and heat stable, were reduced by trypsin but not by dextran-coated charcoal. The effect of purified growth factors on DNA synthesis in primary cultures of rat uterine cells was examined. Epidermal growth factor (EGF), basic fibroblasts growth factor (bFGF), and transforming growth factor-{beta} (TGF{beta}) had no effect on {sup 3}H-thymidine incorporation.

  19. Cannabinoids Inhibit the Vascular Endothelial Growth Factor Pathway in Gliomas

    Microsoft Academic Search

    Cristina Blazquez; Luis Gonzalez-Feria; Luis Alvarez; Amador Haro; M. Llanos Casanova; Manuel Guzman

    Cannabinoids inhibit tumor angiogenesis in mice, but the mechanism of their antiangiogenic action is still unknown. Because the vascular endo- thelial growth factor (VEGF) pathway plays a critical role in tumor angiogenesis, here we studied whether cannabinoids affect it. As a first approach, cDNA array analysis showed that cannabinoid administration to mice bearing s.c. gliomas lowered the expression of various

  20. Epidermal Growth Factor Reduces Hepatic Sequelae in Experimental Necrotizing Enterocolitis

    Microsoft Academic Search

    Melissa D. Halpern; Hana Holubec; Jessica A. Clark; Tara A. Saunders; Catherine S. Williams; Katerina Dvorak; Bohuslav Dvorak

    2006-01-01

    Background and Aim: Neonatal necrotizing enterocolitis (NEC) is the most common gastrointestinal disease of premature infants. We recently demonstrated that the gut\\/liver axis plays an important role in the pathophysiology of NEC through the release of inflammatory mediators into the intestinal lumen. We have also shown that supplementation of formula with epidermal growth factor (EGF) dramatically decreases ileal pathology associated

  1. ARTICLE IN PRESS Platelet-derived growth factor regulates oligodendrocyte

    E-print Network

    Richardson, William D.

    ARTICLE IN PRESS Platelet-derived growth factor regulates oligodendrocyte progenitor numbers such as multiple sclerosis, it will be important to understand the mechanisms that control oligodendrocyte­xxx sclerosis (MS) (Franklin, 2002; Ludwin, 1987). A major source of remyelinating oligodendrocytes is thought

  2. Adrenalectomy Decreases Nerve Growth Factor in Young Adult Rat Hippocampus

    Microsoft Academic Search

    Luigi Aloe

    1989-01-01

    The effect of adrenalectomy on the level of nerve growth factor (NGF) in the hippocampus and on the distribution of choline acetyltransferase immunoreactivity in forebrain cholinergic neurons of developing rats was studied. Biological and immunohistochemical determinations indicated that in 40-day-old rats, adrenalectomy reduced the NGF level in the hippocampus and the choline acetyltransferase immunoreactivity in the septal lateral bands. Furthermore,

  3. Mast Cells Synthesize, Store, and Release Nerve Growth Factor

    Microsoft Academic Search

    A. Leon; A. Buriani; R. dal Toso; M. Fabris; S. Romanello; L. Aloe; R. Levi-Montalcini

    1994-01-01

    Mast cells and nerve growth factor (NGF) have both been reported to be involved in neuroimmune interactions and tissue inflammation. In many peripheral tissues, mast cells interact with the innervating fibers. Changes in the behaviors of both of these elements occur after tissue injury\\/inflammation. As such conditions are typically associated with rapid mast cell activation and NGF accumulation in inflammatory

  4. Transforming growth factor ? as a therapeutic target in systemic sclerosis

    Microsoft Academic Search

    Boris Pasche; John Varga

    2009-01-01

    Transforming growth factor ? (TGF-?) is a pleiotropic cytokine with vital homeostatic functions. Aberrant TGF-? expression is implicated in the pathogenesis of fibrosis in systemic sclerosis (SSc); thus, TGF-? represents a molecular therapeutic target in this disease. Anti-TGF-? monoclonal antibody has been evaluated in a small trial of early SSc, with disappointing results. Antibodies against the ?v?6 integrin that prevent

  5. Expression of vascular endothelial growth factor in experimental choroidal neovascularization

    Microsoft Academic Search

    Tatsuro Ishibashi; Yasuaki Hata; Hiroshi Yoshikawa; Kazunori Nakagawa; Katsuo Sueishi; Hajime Inomata

    1997-01-01

    • Background: Although the choroidal neovascularization (CNV) is a common pathologic feature of a number of different eye diseases, its pathological mechanisms have not been fully elucidated. We investigated the expression of vascular endothelial growth factor (VEGF) in CNV using an experimental primate model. • Method: CNV was induced by intense laser photocoagulation in four monkey eyes. Single eyes were

  6. Vascular endothelial growth factor expression in choroidal neovascularization in rats

    Microsoft Academic Search

    Xianjin Yi; Nahoko Ogata; Masayuki Komada; Chikako Yamamoto; Kanji Takahashi; Koichiro Omori; Masanobu Uyama

    1997-01-01

    Background: The pathogenesis of choroidal neovascularization is largely unknown. We investigated vascular endothelial growth factor (VEGF) expression in laser-induced choroidal neovascularization (CNV) in rats.Methods: Intense krypton laser photocoagulation was applied to the posterior poles of the eyes of pigmented rats to induce CNV, which was confirmed by fluorescein angiography and histopathology. The eyeballs were enucleated 1, 3, 7, 14 and

  7. Vascular endothelial growth factor gene polymorphism and implantation failure

    Microsoft Academic Search

    Cammi Goodman; RS Jeyendran; CB Coulam

    2008-01-01

    Implantation failure is the most frequent cause of lack of pregnancy after IVF and embryo transfer. Successful implantation requires the invading blastocyst to stimulate its own blood supply through angiogenesis. Vascular endothelial growth factor (VEGF) is the best-characterized regulator of angiogenesis. Since one polymorphism of the VEGF gene, –1154 G\\/A, has been previously suggested to be associated with recurrent spontaneous

  8. Effects of growth factors and receptor blockade on gastrointestinal cancer

    Microsoft Academic Search

    R J Playford; H Wassan; S Ghosh

    2004-01-01

    The advent of recombinant peptide technology offers the potential to use one or several peptides to treat a variety of gastrointestinal conditions. However, although cell culture and animal models have shown proof of concept, we are still at a relatively early stage in translating their use to standard clinical practice. Similarly, peptide and non-peptide antagonists of growth factor receptors show

  9. Growth and Demographic Change: Do Environmental Factors Matter?

    Microsoft Academic Search

    Dimitrios Varvarigos; Intan Zanariah Zakaria

    2011-01-01

    We incorporate health-damaging pollution into a three period overlapping generations model in which life expectancy, fertility and economic growth are all endogenous. We show that environmental factors can cause significant changes to the economy’s demographics. In particular, the entrepreneurial choice of less polluting production processes, induced by environmental policy, can account for such demographic changes as higher longevity and lower

  10. Vascular endothelial growth factor increases neurogenesis after traumatic brain injury

    Microsoft Academic Search

    Orli Thau-Zuchman; Esther Shohami; Alexander G Alexandrovich; Ronen R Leker

    2010-01-01

    Activation of endogenous stem cells has been proposed as a novel form of therapy in a variety of neurologic disorders including traumatic brain injury (TBI). Vascular endothelial growth factor (VEGF) is expressed in the brain after TBI and serves as a potent activator of angiogenesis and neurogenesis. In this study, we infused exogenous VEGF into the lateral ventricles of mice

  11. Fatty acids modulate transforming growth factor-  activity and plasma clearance

    Microsoft Academic Search

    Thai-Yen Ling; Yen-Hua Huang; Ming-Chih Lai; Shuan Shian Huang; Jung San

    2003-01-01

    The activity and plasma clearance of transforming growth factor (TGF)-? are known to be regulated by activated ?2-macroglobulin (?2M*). This has been implicated in pathophysiological processes, but no small molecule compounds have been reported to modulate TGF-? activity by affecting the interaction of TGF-? and ?2M*. Here, we demonstrate that fatty acids are capable of inhibiting complex formation of TGF-?

  12. Modelling hematopoiesis mediated by growth factors: Delay equations describing periodic

    E-print Network

    Boyer, Edmond

    and reg- ulation of blood cells. It is based upon differentiation of stem cells under the action of growth factors. A mathematical approach of this process is proposed to carry out explanation on some blood diseases, characterized by oscillations in circulating blood cells. A system of three differential

  13. Controlled growth factor release from synthetic extracellular matrices

    NASA Astrophysics Data System (ADS)

    Lee, Kuen Yong; Peters, Martin C.; Anderson, Kenneth W.; Mooney, David J.

    2000-12-01

    Polymeric matrices can be used to grow new tissues and organs, and the delivery of growth factors from these matrices is one method to regenerate tissues. A problem with engineering tissues that exist in a mechanically dynamic environment, such as bone, muscle and blood vessels, is that most drug delivery systems have been designed to operate under static conditions. We thought that polymeric matrices, which release growth factors in response to mechanical signals, might provide a new approach to guide tissue formation in mechanically stressed environments. Critical design features for this type of system include the ability to undergo repeated deformation, and a reversible binding of the protein growth factors to polymeric matrices to allow for responses to repeated stimuli. Here we report a model delivery system that can respond to mechanical signalling and upregulate the release of a growth factor to promote blood vessel formation. This approach may find a number of applications, including regeneration and engineering of new tissues and more general drug-delivery applications.

  14. Growth factor delivery for oral and periodontal tissue engineering

    PubMed Central

    Kaigler, Darnell; Cirelli, Joni A; Giannobile, William V

    2008-01-01

    The treatment of oral and periodontal diseases and associated anomalies accounts for a significant proportion of the healthcare burden, with the manifestations of these conditions being functionally and psychologically debilitating. Growth factors are critical to the development, maturation, maintenance and repair of craniofacial tissues, as they establish an extracellular environment that is conducive to cell and tissue growth. Tissue-engineering principles aim to exploit these properties in the development of biomimetic materials that can provide an appropriate microenvironment for tissue development. These materials have been constructed into devices that can be used as vehicles for delivery of cells, growth factors and DNA. In this review, different mechanisms of drug delivery are addressed in the context of novel approaches to reconstruct and engineer oral- and tooth-supporting structures, namely the periodontium and alveolar bone. PMID:16948560

  15. Cell-Mediated Delivery of Fibroblast Growth Factor2 and Vascular Endothelial Growth Factor onto the Chick Chorioallantoic Membrane: Endothelial Fenestration and Angiogenesis

    Microsoft Academic Search

    Domenico Ribatti; Beatrice Nico; Lucia Morbidelli; Sandra Donnini; Marina Ziche; Angelo Vacca; Luisa Roncali; Marco Presta

    2001-01-01

    Fibroblast growth factor-2 (FGF2) and vascular endothelial growth factor (VEGF) exert their angiogenic activity by interacting with endothelial cells in a distinct manner. In this study, we investigated the morphological features of endothelial cells of the chick embryo chorioallantoic membrane (CAM) microvasculature after stimulation with FGF2 or VEGF. In order to provide a continuous delivery of the growth factor, we

  16. Expression of acidic fibroblast growth factor (aFGF) and fibroblast growth factor receptor 4 (FGFR4) in breast fibroadenomas

    PubMed Central

    Rosa, S; Sessa, F; Colombo, L; Tibiletti, M; Furlan, D; Capella, C

    2001-01-01

    Background/Aim—Fibroadenomas are benign tumours composed of both glandular and fibrous tissue. The mechanisms regulating the growth of these tumours and the relation between the stromal and epithelial cells are poorly understood. Acidic fibroblast growth factor (aFGF) is a well known fibroblast activator, which acts through four specific cell surface receptors, among which, fibroblast growth factor receptor 4 (FGFR4) is highly specific. The aim of this study was to evaluate the distribution of aFGF and FGFR4 in specific cell types of fibroadenomas to understand their possible role in the growth of these breast lesions. Methods—Formalin fixed and paraffin wax embedded tissues from 15 fibroadenomas and peritumoral normal breasts were investigated for the expression of aFGF and FGFR4 using immunohistochemistry. The presence of aFGF mRNA was also investigated using in situ hybridisation. Results— Immunoreactivity for aFGF and FGFR4 was seen in epithelial cells, but it was lacking in myoepithelial cells of both normal tissues and fibroadenomas. Strong FGFR4 immunoreactivity was found in stromal fibroblasts, which were also weakly positive for aFGF. aFGF mRNA was detected in epithelial cells and in some stromal fibroblasts. Conclusions—These results suggest a paracrine/autocrine modulation of epithelial and stromal cells of fibroadenomas through an aFGF–FGFR4 interaction. This interaction might regulate various cell functions and the growth of fibroadenomas. Key Words: acidic fibroblast growth factor • fibroblast growth factor receptor 4 • fibroadenoma • human breast PMID:11271786

  17. Structure of the receptor for platelet-derived growth factor helps define a family of closely related growth factor receptors

    Microsoft Academic Search

    Y. Yarden; J. A. Escobedo; W.-J. Kuang; T. L. Yang-Feng; T. O. Daniel; P. M. Tremble; E. Y. Chen; M. E. Ando; R. N. Harkins; U. Francke; V. A. Fried; A. Ullrich; L. T. Williams

    1986-01-01

    The primary structure of the receptor for platelet-derived growth factor (PDGF), determined by means of cloning a cDNA that encodes the murine pre-PDGF receptor, is closely related to that of the v-kit oncogene product and the receptor for macrophage colony stimulating factor (CSF-1). Common structural features include the presence of long sequences that interrupt the tyrosine-specific protein kinase domains of

  18. Modulation of NFAT-5, an outlying member of the NFAT family, in human keratinocytes and skin

    PubMed Central

    Al-Daraji, Wael I; Afolayan, John; Zelger, Bettina G; Abdellaoui, Adel; Zelger, Bernhard

    2009-01-01

    Background Cyclosporin A (CsA) and tacrolimus block T cell activation by inhibiting the phosphatase calcineurin and preventing translocation from the cytoplasm to the nucleus of the transcription factor Nuclear Factor of Activated T cells (NFAT). NFAT compose a family of transcription factors that are turned on during T cell activation. Aims To study the expression of NFAT-5 mRNA and protein in normal human keratinocytes and to investigate the cellular and subcellular pattern of expression of NFAT-5 in normal human skin and psoriasis, and analyze effects of different agonists and ultraviolet radiation on NFAT-5 in normal human skin. Methods Tissue cultures, Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR), Western analysis, immunostaining, confocal microscopy. Results Sequencing of RT-PCR products confirmed the identity of the product that showed 100 % homology with the predicted NFAT-5 sequence. anti-NFAT-5 mainly detected a single band in cultured keratinocytes and dermal fibroblasts using Western analysis. Immunohistochemistry showed that epidermal keratinocytes and dermal fibroblasts in normal human and psoriatic skin express NFAT-5. NFAT-5 showed predominantly nuclear localization in epidermal keratinocytes and dermal fibroblasts within five normal adult skin biopsies. Our data also suggest that UV irradiation reduces NFAT-5 nuclear localization within the epidermis. Unlike NFAT 1-4, NFAT-5/TonEBP was localized to both nucleus and cytoplasm of cultured keratinocytes. Cyclosporin A induces nuclear membrane translocation of NFAT-5 in cultured keratinocytes and raffinose (a hypertonicity inducing agent) induces more nuclear localization of NFAT-5 compared to untreated cells. In addition, differentiation-promoting agonists that induce sustained rise in intracellular calcium did not result in changes in NFAT-5 localization in cultured keratinocytes. Conclusion These studies provide the first observation of expression of NFAT-5/TonEBP mRNA protein in cultured keratinocytes and dermal fibroblasts and possible functional regulation in cultured keratinocytes. CsA and raffinose effects on NFAT-5/TonEBP in cultured keratinocytes suggest diverse intracellular signaling pathways for NFAT-5/TonEBP in these cells, and that NFAT-5/TonEBP might function to translate different extracellular stimuli into appropriate functional responses. PMID:19956430

  19. Overexpression of Vascular Permeability Factor\\/Vascular Endothelial Growth Factor and its Receptors in Psoriasis

    Microsoft Academic Search

    Michael Detmar; Lawrence F. Brown; Kevin P. Claffey; Kiang-Teck Yeo; Olivier Kocher; Robert W. Jackman; Brygida Berse; Harold F. Dvorak

    1994-01-01

    Summary Psoriatic skin is characterized by microvascular hyperpermeability and angioproliferation, but the mechanisms responsible are unknown. We report here that the hyperplastic epidermis of psoriatic skin expresses strikingly increased amounts of vascular permeability factor (VPF; vascular endothelial growth factor), a selective endothelial cell mitogen that enhances microvascular permeability. Moreover, two VPF receptors, kdr and fit-l, are overexpressed by papillary dermal

  20. The ? isoform of protein kinase C inhibits UV-induced activation of caspase-3 in normal human keratinocytes

    Microsoft Academic Search

    Miyoko Matsumura; Naoya Tanaka; Toshio Kuroki; Masamitsu Ichihashi; Motoi Ohba

    2003-01-01

    Protein kinase C (PKC) fulfills a central role in the decision of cell fate in keratinocytes. Both PKC? and PKC? induce growth inhibition and differentiation of normal human keratinocytes (NHK). Here we show that PKC? and PKC? play opposite roles in UVB-induced apoptosis in NHK. PKC? enhanced UVB-induced caspase-3 activity, while overexpression of PKC? reduced it. In keeping with these

  1. Expression of basic fibroblast growth factor is associated with poor outcome in non-Hodgkin's lymphoma.

    PubMed

    Pazgal, I; Zimra, Y; Tzabar, C; Okon, E; Rabizadeh, E; Shaklai, M; Bairey, O

    2002-06-01

    It is now clear that angiogenesis and angiogenesis factors are important in the pathogenesis of haematological malignancies. High pretreatment levels of serum basic fibroblast growth factor have been shown to be associated with poor prognosis in patients with non-Hodgkin's lymphoma. The aim of this study was to evaluate whether non-Hodgkin's lymphoma cells express basic fibroblast growth factor and/or its receptor (fibroblast growth factor receptor-1) and whether basic fibroblast growth factor expression correlates with basic fibroblast growth factor serum levels, intratumoral microvessel density, and patient outcome. We measured basic fibroblast growth factor by enzyme-linked immunosorbent assay in sera taken from 58 patients with non-Hodgkin's lymphoma before treatment and in 19 of them also after treatment. Pathological specimens at diagnosis were evaluated by immunohistochemistry staining using polyoclonal antibody against factor-VIII-related antigen, basic fibroblast growth factor and fibroblast growth factor receptor-1 to determine the expression of the microvessel count and basic fibroblast growth factor and fibroblast growth factor receptor-1. The lymphoma specimens demonstrated positive staining for basic fibroblast growth factor (in 23%) and fibroblast growth factor receptor-1 (in 58.5%). The patients who expressed basic fibroblast growth factor had a significantly worse progression-free and overall survival than those who did not (P=0.003 and P=0.03 respectively), while patients expressing fibroblast growth factor receptor-1 were less likely to achieve complete remission than those lacking the receptor (33% vs 65%, P=0.047). There was no correlation of basic fibroblast growth factor staining with either serum basic fibroblast growth factor levels or microvessel count. Basic fibroblast growth factor serum levels did not change significantly after treatment These results suggest that non-Hodgkin's lymphoma specimens express basic fibroblast growth factor and its receptor (fibroblast growth factor receptor-1) and this expression is associated with poor patient outcome. PMID:12087465

  2. Vascular Endothelial growth factor signaling in hypoxia and Inflammation

    PubMed Central

    Ramakrishnan, S.; Anand, Vidhu; Roy, Sabita

    2014-01-01

    Infection, cancer and cardiovascular diseases are the major causes for morbidity and mortality in the United States according to the Center for Disease Control. The underlying etiology that contributes to the severity of these diseases is either hypoxia induced inflammation or inflammation resulting in hypoxia. Therefore, molecular mechanisms that regulate hypoxia-induced adaptive responses in cells are important areas of investigation. Oxygen availability is sensed by molecular switches which regulate synthesis and secretion of growth factors and inflammatory mediators. As a consequence, tissue microenvironment is altered by reprogramming metabolic pathways, angiogenesis, vascular permeability, pH homeostasis to facilitate tissue remodeling. Hypoxia inducible factor (HIF) is the central mediator of hypoxic response. HIF regulates several hundred genes and vascular endothelial growth factor (VEGF) is one of the primary target genes. Understanding the regulation of HIF and its influence on inflammatory response offers unique opportunities for drug development to modulate inflammation and ischemia in pathological conditions. PMID:24610033

  3. Quantitation of growth factors in ossein-mineral-compound.

    PubMed

    Stepan, J J; Mohan, S; Jennings, J C; Wergedal, J E; Taylor, A K; Baylink, D J

    1991-01-01

    Study was undertaken to identify polypeptide factors in the commercially available ossein-mineral-compound and to see if they are present in a biologically relevant quantity. Using the guanidine-EDTA extraction, 35.7 +/- 0.1 mg proteins were obtained from 1 g of the ossein-mineral-compound. At concentration 1 micrograms/ml, guanidine-EDTA-extractable proteins stimulated the incorporation of thymidine into DNA by human bone cells to 581 +/- 122% (p less than 0.001) of that by bovine serum albumin-treated control cells, decreasing thereafter. Similarly, it stimulated the activity of alkaline phosphatase in the human bone cells. Growth factors IGF-I, IGF-II, and TGF-beta were identified in the ossein-mineral-compound. This leads to speculation regarding possible role of growth factors in explaining the beneficial effects of the compound in retarding bone loss in patients with osteoporosis. PMID:1653384

  4. Stimulation of body weight increase and epiphyseal cartilage growth by insulin like growth factor

    NASA Technical Reports Server (NTRS)

    Ellis, S.

    1981-01-01

    The ability of insulin-like growth factor (IGF) to induce growth in hypophysectomized immature rats was tested by continuous infusion of the partially purified factor at daily doses of 6, 21, and 46 mU for an 8-day period. A dose-dependent growth of the proximal epiphyseal cartilage of the tibia and an associated stimulation of the primary spongiosa were produced by these amounts of IGF. The two highest doses of IGF also resulted in dose-dependent increases of body weight. Gel permeation of the sera at neutrality showed that the large-molecular-weight IGF binding protein was not induced by the infusion of IGF, whereas it ws generated in the sera of hypophysectomized rats that were infused with daily doses of 86 mU of human growth hormone.

  5. Nerve growth factor and galantamine ameliorate early signs of neurodegeneration in anti-nerve growth factor mice

    Microsoft Academic Search

    Simona Capsoni; Sabina Giannotta; Antonino Cattaneo

    2002-01-01

    Phenotypic knockout of nerve growth factor (NGF) activity in transgenic anti-NGF mice (AD11 mice) results in a progressive neurodegenerative phenotype resembling Alzheimer's disease. In this article, we examine whether and how the progressive neurodegenerative phenotype of AD11 mice could be prevented or ameliorated by pharmacological treatments with NGF or the cholinergic agonist galantamine, at a relatively early phase of Alzheimer's

  6. Epidermal Growth Factor Receptor Activation by Epidermal Growth Factor Mediates Oxidant-Induced Goblet Cell Metaplasia in Human Airway Epithelium

    Microsoft Academic Search

    S. Marina Casalino-Matsuda; Maria E. Monzon; Rosanna M. Forteza

    2006-01-01

    Mucus overproduction in inflammatory and obstructive airway dis- eases is associated with goblet cell (GC) metaplasia in airways. Although the mechanisms involved in GC metaplasia and mucus hypersecretion are not completely understood, association with oxidative stress and epidermal growth factor receptor (EGFR) sig- naling has been reported. To explore the mechanisms involved in oxidative stress-induced GC metaplasia, cultures of differentiated

  7. Endothelial Cell Death and Decreased Expression of Vascular Endothelial Growth Factor and Vascular Endothelial Growth Factor Receptor 2 in Emphysema

    Microsoft Academic Search

    YASUNORI KASAHARA; RUBIN M. TUDER; CARLYNE D. COOL; DAVID A. LYNCH; SONIA C. FLORES; NORBERT F. VOELKEL

    2001-01-01

    Emphysema due to cigarette smoking is characterized by a loss of alveolar structures. We hypothesize that the disappearance of al- veoli involves apoptosis of septal endothelial cells and a decreased expression of lung vascular endothelial growth factor (VEGF) and its receptor 2 (VEGF R2). By terminal transferase dUTP nick end la- beling (TUNEL) in combination with immunohistochemistry, we found that

  8. Epidermal Homeostasis: The Role of the Growth Hormone and Insulin-Like Growth Factor Systems

    Microsoft Academic Search

    STEPHANIE R. EDMONDSON; SUSAN P. THUMIGER; GEORGE A. WERTHER; CHRISTOPHER J. WRAIGHT

    2003-01-01

    GH and IGF-I and -II were first identified by their endocrine activity. Specifically, IGF-I was found to mediate the linear growth-promoting actions of GH. It is now evident that these two growth factor systems also exert widespread activity throughout the body and that their actions are not always interconnected. The literature highlights the importance of the GH and IGF systems

  9. Aging and the growth hormone\\/insulin like growth factor-I axis

    Microsoft Academic Search

    Mark Sherlock; Andrew A. Toogood

    2007-01-01

    Growth hormone release and IGF-I synthesis decrease with increasing age. The regulation of the GH\\/IGF-I system is dependant\\u000a on the integrity of the hypothalamus, pituitary and liver. During aging there are several changes which contribute to the\\u000a decline in GH\\/IGF-I including changes in signal to the somatotrophs from growth hormone releasing hormone, somatostatin and\\u000a other factors such as body composition,

  10. Growth Factors Can Influence Cell Growth and Survival through Effects on Glucose Metabolism

    Microsoft Academic Search

    MATTHEW G. VANDER HEIDEN; DAVID R. PLAS; JEFFREY C. RATHMELL; CASEY J. FOX; MARIAN H. HARRIS; CRAIG B. THOMPSON

    2001-01-01

    Cells from multicellular organisms are dependent upon exogenous signals for survival, growth, and prolif- eration. The relationship among these three processes was examined using an interleukin-3 (IL-3)-dependent cell line. No fixed dose of IL-3 determined the threshold below which cells underwent apoptosis. Instead, increasing growth factor concentrations resulted in progressive shortening of the G1 phase of the cell cycle and

  11. The effects of growth factors on testicular germ cell apoptosis in the stallion

    E-print Network

    Donnelly, Casey Leanne

    2002-01-01

    /growth factors such as interleukin-1 alpha (IL-1 cr) and IL- 6, nerve growth factor beta (NGFP), epidermal growth factor (EGF), fibroblast growth factor alpha (FGFct), FGFP, insulin-like growth factor I (IGF-I), IGF-II, and fete calf serum (FCS) on germ cell... in maintaining spermatogenesis, and FGF influences cellular growth and differentiation in spermatogenesis. Insulin-like growth factor and NGF are both highly expressed in the testes. Mouse spermatocytes and early spermatids secrete and express NGF. Insulin...

  12. Comparison of transforming growth factor ? and a human tumour-derived suppressor factor

    Microsoft Academic Search

    Shaw S. Somers; Julian F. Dye; Pierre J. Guillou

    1991-01-01

    Summary Serum-free supernatants from the human melanoma cell line G361 contain a factor that can potently suppress the generation of tumouricidal lymphokine-activated killer (LAK) cells in response to interleukin-2. To characterise the suppressive factor of tumour origin we performed a number of physicochemical and functional comparisons with another immunosuppressive protein, transforming growth factor ß (TGFß). The bioactivity of tumour-derived suppressor

  13. Transforming growth factor (TGF)-. alpha. in human milk

    SciTech Connect

    Okada, Masaki; Wakai, Kae; Shizume, Kazuo (Research Institute for Growth Sciences, Tokyo (Japan)); Iwashita, Mitsutoshi (Tokyo Women's Medical College (Japan)); Ohmura, Eiji; Kamiya, Yoshinobu; Murakami, Hitomi; Onoda, Noritaka; Tsushima, Toshio

    1991-01-01

    Transforming growth factor (TGF)-{alpha} and epidermal growth factor (EGF) were measured in human milk by means of homologous radioimmunoassay. As previously reported, EGF concentration in the colostrum was approximately 200 ng/ml and decreased to 50 ng/ml by day 7 postpartum. The value of immunoreactive (IR)-TGF-{alpha} was 2.2-7.2 ng/ml, much lower than that of EGF. In contrast to EGF, the concentration of IR-TGF-{alpha} was fairly stable during the 7 postpartum days. There was no relationship between the concentrations of IR-TGF-{alpha} and IR-EGF, suggesting that the regulatory mechanism in the release of the two growth factors is different. On gel-chromatography using a Sephadex G-50 column, IR-EGF appeared in the fraction corresponding to that of authentic human EGF, while 70%-80% of the IR-TGF-{alpha} was eluted as a species with a molecular weight greater than that of authentic human TGF-{alpha}. Although the physiological role of TGF-{alpha} in milk is not known, it is possible that it is involved in the development of the mammary gland and/or the growth of newborn infants.

  14. The Role of p21 in Apoptosis, Proliferation, Cell Cycle Arrest, and Antioxidant Activity in UVB-Irradiated Human HaCaT Keratinocytes

    PubMed Central

    Chen, Aijun; Huang, Xin; Xue, Zhenan; Cao, Di; Huang, Kun; Chen, Jin; Pan, Yun; Gao, Yongliang

    2015-01-01

    Background Skin cancer is the most common cancer in the United States, and ultraviolet B (UVB) radiation-induced DNA damage is the major environmental factor underlying skin cancer development. p21, a p53-inducible protein, plays a key role in the cellular response to UVB-induced DNA damage. Material/Methods Through p21 silencing and overexpression, we investigated the role of p21 in apoptosis, proliferation, cell cycle arrest, and oxidative stress in UVB-irradiated HaCaT keratinocytes. Results We found that UVB exposure induced significant p21 downregulation (p<0.05) and was associated with significantly increased apoptosis, significantly decreased proliferation, and significantly increased G2 phase arrest (p<0.05) in UVB-irradiated HaCaT keratinocytes. p21 silencing significantly promoted apoptosis, significantly inhibited G2 phase arrest, and significantly inhibited proliferation (p<0.05), but after UVB irradiation, p21 silencing demonstrated a less significant pro-apoptotic effect and a more significant inhibition of G2 phase arrest (p<0.05), which was reflected in significantly higher proliferative activity (p<0.05). p21 overexpression acted in an anti-apoptotic manner in the absence of UVB-induced DNA damage but acted in a pro-apoptotic manner in the presence of UVB-induced DNA damage, displaying an “antagonistic duality” similar to other growth-promoting oncoproteins. p53 expression mirrored p21 expression, suggesting a regulatory feedback mechanism between p21 and p53 expression. p21 overexpression significantly downregulated glutathione peroxidase and superoxide dismutase antioxidant activity (p<0.05) while significantly upregulating hydrogen peroxide and malondialdehyde content (p<0.05), suggesting a role in decreasing antioxidant defense capabilities in UVB-irradiated HaCaT keratinocytes. Conclusions These findings reveal that p21 may play a key role in HaCaT keratinocytes’ response to UVB exposure. PMID:25925725

  15. Downregulation of TNIP1 Expression Leads to Increased Proliferation of Human Keratinocytes and Severer Psoriasis-Like Conditions in an Imiquimod-Induced Mouse Model of Dermatitis

    PubMed Central

    Chen, Yan; Yan, Heng; Song, Zhiqiang; Chen, Fangru; Wang, Huan; Niu, Jun; Shi, Xiaowei; Zhang, Dongmei; Zhang, Na; Zhai, Zhifang; Zhong, Baiyu; Cheng, Liangjin; Qian, Tian; Hao, Fei

    2015-01-01

    Psoriasis is a chronic, inflammatory skin disease involving both environmental and genetic factors. According to genome-wide association studies (GWAS), the TNIP1 gene, which encodes the TNF-?–induced protein 3-interacting protein 1 (TNIP1), is strongly linked to the susceptibility of psoriasis. TNIP1 is a widely expressed ubiquitin sensor that binds to the ubiquitin-editing protein A20 and restricts TNF- and TLR-induced signals. In our study, TNIP1 expression decreased in specimens of epidermis affected by psoriasis. Based on previous studies suggesting a role for TNIP1 in modulating cancer cell growth, we investigated its role in keratinocyte proliferation, which is clearly abnormal in psoriasis. To mimic the downregulation or upregulation of TNIP1 in HaCaT cells and primary human keratinocytes (PHKs), we used a TNIP1 specific small interfering hairpin RNA (TNIP1 shRNA) lentiviral vector or a recombinant TNIP1 (rTNIP1) lentiviral vector, respectively. Blocking TNIP1 expression increased keratinocyte proliferation, while overexpression of TNIP1 decreased keratinocyte proliferation. Furthermore, we showed that TNIP1 signaling might involve extracellular signal-regulated kinase1/2 (Erk1/2) and CCAAT/enhancer-binding protein ? (C/EBP?) activity. Intradermal injection of TNIP1 shRNA in BALB/c mice led to exaggerated psoriatic conditions in imiquimod (IMQ)-induced psoriasis-like dermatitis. These findings indicate that TNIP1 has a protective role in psoriasis and therefore could be a promising therapeutic target. PMID:26046540

  16. Vascular endothelial growth factor-B in physiology and disease.

    PubMed

    Bry, Maija; Kivelä, Riikka; Leppänen, Veli-Matti; Alitalo, Kari

    2014-07-01

    Vascular endothelial growth factor-B (VEGF-B), discovered over 15 years ago, has long been seen as one of the more ambiguous members of the VEGF family. VEGF-B is produced as two isoforms: one that binds strongly to heparan sulfate in the pericellular matrix and a soluble form that can acquire binding via proteolytic processing. Both forms of VEGF-B bind to VEGF-receptor 1 (VEGFR-1) and the neuropilin-1 (NRP-1) coreceptor, which are expressed mainly in blood vascular endothelial cells. VEGF-B-deficient mice and rats are viable without any overt phenotype, and the ability of VEGF-B to induce angiogenesis in most tissues is weak. This has been a puzzle, as the related placenta growth factor (PlGF) binds to the same receptors and induces angiogenesis and arteriogenesis in a variety of tissues. However, it seems that VEGF-B is a vascular growth factor that is more tissue specific and can have trophic and metabolic effects, and its binding to VEGFR-1 shows subtle but important differences compared with that of PlGF. VEGF-B has the potential to induce coronary vessel growth and cardiac hypertrophy, which can protect the heart from ischemic damage as well as heart failure. In addition, VEGF-B is abundantly expressed in tissues with highly active energy metabolism, where it could support significant metabolic functions. VEGF-B also has a role in neuroprotection, but unlike other members of the VEGF family, it does not have a clear role in tumor progression. Here we review what is hitherto known about the functions of this growth factor in physiology and disease. PMID:24987005

  17. Development of growth factor fusion proteins for cell-triggered drug delivery

    Microsoft Academic Search

    Shelly E. Sakiyama-Elbert; Alyssa Panitch; Jeffrey A. Hubbell

    2001-01-01

    The goal of this research was to develop an approach to growth factor delivery that would allow the stable incorporation of growth factors within a cell in-growth matrix in a manner such that local enzymatic activity associated with tissue regeneration could trigger growth factor release. We investigated this approach in the context of peripheral nerve regeneration by designing modified beta-nerve

  18. DMSO induces apoptosis in SV40-transformed human keratinocytes, but not in normal keratinocytes

    Microsoft Academic Search

    Manabu Koike; Keiko Ishino; Yohko Kohno; Tetsuhiko Tachikawa; Tonja Kartasova; Toshio Kuroki; Nam-ho Huh

    1996-01-01

    We found that dimethyl-sulfoxide (DMSO) at concentrations of 2.5% induced apoptosis in SV40-immortalized human keratinocytes, while normal keratinocytes were arrested at the boundary of G1\\/S phase under the same conditions. DMSO-induced apoptosis in SV-40 immortalized keratinocytes was not associated with change in phospohrylated state of the retinoblastoma susceptibility gene. When SV40-immortalized cells were treated with 2.5% DMSO, dissociation of the

  19. Exosomes released by keratinocytes modulate melanocyte pigmentation

    PubMed Central

    Cicero, Alessandra Lo; Delevoye, Cédric; Gilles-Marsens, Floriane; Loew, Damarys; Dingli, Florent; Guéré, Christelle; André, Nathalie; Vié, Katell; van Niel, Guillaume; Raposo, Graça

    2015-01-01

    Cells secrete extracellular vesicles (EVs), exosomes and microvesicles, which transfer proteins, lipids and RNAs to regulate recipient cell functions. Skin pigmentation relies on a tight dialogue between keratinocytes and melanocytes in the epidermis. Here we report that exosomes secreted by keratinocytes enhance melanin synthesis by increasing both the expression and activity of melanosomal proteins. Furthermore, we show that the function of keratinocyte-derived exosomes is phototype-dependent and is modulated by ultraviolet B. In sum, this study uncovers an important physiological function for exosomes in human pigmentation and opens new avenues in our understanding of how pigmentation is regulated by intercellular communication in both healthy and diseased states. PMID:26103923

  20. Osteopontin contributes to hepatocyte growth factor-induced tumor growth and metastasis formation

    Microsoft Academic Search

    E. V Ariztia; V Subbarao; D. B Solt; A. W Rademaker; A. P Iyer; Z. N Oltvai

    2003-01-01

    The cytokine hepatocyte growth factor (HGF)\\/scatter factor-1 and its cognate receptor, Met, are involved in the etiology and progression of many types of cancer. Despite recent advances in understanding the signal transduction pathways activated by HGF, the mechanism by which HGF exerts its tumorigenic effect is not well understood. To identify proteins that may be involved in mediating HGF-induced cell

  1. Human papillomavirus 16 E6/E7-immortalized human gingival keratinocytes with epithelial mesenchymal transition acquire increased expression of cIAP-1, Bclx and p27(Kip1).

    PubMed

    Chamulitrat, Walee; Sattayakhom, Apsorn; Herold-Mende, Christel; Herold-Mended, Christel; Stremmel, Wolfgang

    2009-12-01

    Epithelial mesenchymal transition (EMT) has been implicated in neoplastic invasion and metastasis. We have previously generated six cell lines from human gingival mucosal keratinocytes immortalized by E6/E7 of human papillomavirus type 16. Ldk and NuB1 lines represented EMT phenotype and other four lines represented cobblestone non-EMT phenotype. These cell lines were utilized as model cells to determine whether inhibitors of apoptosis proteins and cell-cycle regulators were molecular players during EMT. EMT cells exhibited increased expression of vimentin, vascular endothelial growth factor (VEGF) receptor1 and the ability to form tubules on Matrigel as well as to grow anchorage independently. We found that EMT cells expressed significantly elevated levels of cIAP-1, Bclx and p27(kip) higher than non-EMT cells. These proteins could therefore be used as intrinsic indicators of EMT of human gingival keratinocytes. PMID:19397698

  2. Fibroblast Growth Factor 23 in Long-Duration Spaceflight

    NASA Technical Reports Server (NTRS)

    Bokhari, R.; Zwart, S. R.; Fields, E.; Heer, M.; Sibonga, J.; Smith, S. M.

    2015-01-01

    Many nutritional factors influence bone, from the basics of calcium and vitamin D, to factors which influence bone through acid/base balance, including protein, sodium, and more. Fibroblast growth factor 23 (FGF23) is a recently identified factor, secreted from osteocytes, which is involved in classic (albeit complex) feedback loops controlling phosphorus homeostasis through both vitamin D and parathyroid hormone (PTH) (1, 2). As osteocytes are gravity sensing cells, it is important to determine if there are changes in FGF23 during spaceflight. In extreme cases, such as chronic kidney disease, FGF23 levels are highly elevated. FGF23 imbalances, secondary to dietary influences, may contribute to skeletal demineralization and kidney stone risk during spaceflight.

  3. Growth Factors and Gene Expression: Fresh Insights from Arrays

    NSDL National Science Digital Library

    Caroline S. Hill (Developmental Signalling Laboratory; REV)

    1999-10-12

    Gene array technology allows researchers to evaluate patterns of gene expression at a genome-wide level. Two recent papers have applied this powerful technique to characterize how gene expression is changed in response to growth factors and mitogens. The studies focus on two important questions concerning specificity in signal transduction. First, are the multiple signaling pathways activated by a single growth factor receptor used to activate gene expression, and if so, do these pathways act combinatorially? Second, how does the initial genetic response of a cell to a signal stimulus relate to the patterns of gene expression that determine that cell's ultimate biological response to the stimulus? Hill and Treisman take a critical look at what these array technology studies tell us concerning these questions and discuss technical issues arising from them.

  4. Transforming growth factor beta 1 gene expression in human airways

    Microsoft Academic Search

    J D Aubert; B I Dalal; T R Bai; C R Roberts; S Hayashi; J C Hogg

    1994-01-01

    BACKGROUND--Asthmatic airways have a characteristic deposition of connective tissue under the epithelial basement membrane, but the mediators involved in this alteration are unknown. Several authors have postulated that transforming growth factor beta 1 (TGF-beta 1) could be overexpressed in asthmatic airways. METHODS--Lung samples from 16 asthmatic patients, six patients with chronic obstructive pulmonary disease (COPD), and six non-obstructed smokers were

  5. Vascular Endothelial Growth Factor: Basic Science and Clinical Progress

    Microsoft Academic Search

    NAPOLEONE FERRARA

    2004-01-01

    Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen in vitro and an angiogenic inducer in a variety of in vivo models. Hypoxia has been shown to be a major inducer of VEGF gene transcription. The tyrosine ki- nases Flt-1 (VEGFR-1) and Flk-1\\/KDR (VEGFR-2) are high- affinity VEGF receptors. The role of VEGF in developmental angiogenesis is emphasized by

  6. Hierarchical model of gene regulation by transforming growth factor

    Microsoft Academic Search

    Yaw-Ching Yang; Ester Piek; Jiri Zavadil; Dan Liang; Donglu Xie; Joerg Heyer; Paul Pavlidis; Raju Kucherlapati; Anita B. Roberts; Erwin P. Böttinger

    2003-01-01

    Transforming growth factor s (TGF-s) regulate key aspects of embryonic development and major human diseases. Although Smad2, Smad3, and extracellular signal-regulated kinase (ERK) mitogen-activated protein kinases (MAPKs) have been proposed as key mediators in TGF- signaling, their functional specificities and interactivity in controlling transcriptional programs in different cell types and (patho)physiological contexts are not known. We investigated expression profiles of

  7. Screening for Epidermal Growth Factor Receptor Mutations in Lung Cancer

    Microsoft Academic Search

    Rafael Rosell; Teresa Moran; Cristina Queralt; Rut Porta; Felipe Cardenal; Carlos Camps; Margarita Majem; Guillermo Lopez-Vivanco; Dolores Isla; Mariano Provencio; Amelia Insa; Bartomeu Massuti; Jose Luis Gonzalez-Larriba; Luis Paz-Ares; Isabel Bover; Rosario Garcia-Campelo; Miguel Angel Moreno; Silvia Catot; Christian Rolfo; Noemi Reguart; Ramon Palmero; José Miguel Sánchez; Roman Bastus; Clara Mayo; Jordi Bertran-Alamillo; Miguel Angel Molina; Jose Javier Sanchez; Miquel Taron

    2009-01-01

    Activating mutations in the epidermal growth factor receptor gene (EGFR) confer hy- persensitivity to the tyrosine kinase inhibitors gefitinib and erlotinib in patients with advanced non-small-cell lung cancer. We evaluated the feasibility of large-scale screen- ing for EGFR mutations in such patients and analyzed the association between the mutations and the outcome of erlotinib treatment. Methods From April 2005 through

  8. Angiopoietin-related growth factor antagonizes obesity and insulin resistance

    Microsoft Academic Search

    Masaki Akao; Kunio Yasunaga; Toshimasa Yamauchi; Tohru Morisada; Yasuhiro Ito; Takashi Urano; Yoshishige Kimura; Yoshiaki Kubota; Hiromitsu Maekawa; Takeshi Miyamoto; Keishi Miyata; Shun-ichiro Matsumoto; Juro Sakai; Naomi Nakagata; Motohiro Takeya; Haruhiko Koseki; Yoshihiro Ogawa; Takashi Kadowaki; Toshio Suda; Yuichi Oike

    2005-01-01

    Angiopoietin-related growth factor (AGF), a member of the angiopoietin-like protein (Angptl) family, is secreted predominantly from the liver into the systemic circulation. Here, we show that most (>80%) of the AGF-deficient mice die at about embryonic day 13, whereas the surviving AGF-deficient mice develop marked obesity, lipid accumulation in skeletal muscle and liver, and insulin resistance accompanied by reduced energy

  9. Nerve growth factor, birth outcome and pre-eclampsia

    Microsoft Academic Search

    Anitha Kilari; Savita Mehendale; Hemlata Pisal; Tushar Panchanadikar; Anvita Kale; Sadhana Joshi

    2011-01-01

    The present study compares nerve growth factor (NGF) levels between preeclamptic (PE) (n=86) and normotensive (NT) women (n=105) and their associations with blood pressure and infant size. Maternal plasma NGF levels were reduced (p<0.05) in the PE group as compared to the NT group. Furthermore, NGF levels were reduced in PE mothers delivering low birth weight babies (LBW) as compared

  10. Transforming growth factor-? in T-cell biology

    Microsoft Academic Search

    Leonid Gorelik; Richard A. Flavell

    2002-01-01

    Strict control of T-cell homeostasis is required to permit normal immune responses and prevent undesirable self-targeted responses. Transforming growth factor-? (TGF-?) has been shown to have an essential role in that regulation. Owing to its broad expression, and inhibitory effects on multiple cell types of the immune system, TGF-? regulation is complex. Through advances in cell-specific targeting of TGF-? signalling

  11. The Role of Vascular Endothelial Growth Factor in Angiogenesis

    Microsoft Academic Search

    Napoleone Ferrara; Hans-Peter Gerber

    2001-01-01

    Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen and an angiogenic inducer as well as a mediator of vascular permeability. The biological effects of VEGF are mediated by two tyrosine kinase receptors, Flt-1 (VEGFr-1) and KDR (VEGFR-2). VEGF is essential for developmental angiogenesis and is also required for female reproductive functions and endochondral bone formation. Substantial evidence also

  12. Integrin-mediated activation of latent transforming growth factor ?

    Microsoft Academic Search

    Dean Sheppard

    2005-01-01

    Members of the integrin family recognize a variety of spatially-restricted extracellular ligands. Classically, ligation of integrins activates cytoplasmic signals in the integrin-expressing cell and contributes to cell adhesion, migration, proliferation and survival. At least two members of this family, ?v?6 and ?v?8 perform an additional function, activation of latent complexes of transforming growth factor ?. In effect, this process allows

  13. Factors controlling holocene reef growth: An interdisciplinary approach

    Microsoft Academic Search

    Wolf-Christian Dullo; Marcos Gektidis; Stjepko Golubic; Georg A. Heiss; Heike Kampmann; William Kiene; Dieter K. Kroll; Martin L. Kuhrau; Gudrun Radtke; John G. Reijmer; Götz B. Reinicke; Dietrich Schlichter; Helmut Schuhmacher; Klaus Vogel

    1995-01-01

    Summary  This interim report deals with investigations on key factors controlling reef growth by zoophysiologists, ecologists, paleontologists\\u000a and geologists. The different levels of emphasis are the coral animal and the reef community. The main study area is the Red\\u000a Sea which reaches over 20C latitude up to the northernmost margin of the global coral reef belt. Supplementary results on\\u000a microborer ecology

  14. Heparin Binding Epidermal Growth Factor-Like Growth Factor and PD169316 Prevent Apoptosis in Mouse Embryonic Stem Cells

    PubMed Central

    Krishnamoorthy, Malini; Heimburg-Molinaro, Jamie; Bargo, Ana M.; Nash, Rachel J.; Nash, Rodney J.

    2009-01-01

    Apoptosis or programmed cell death is an important outcome of cell fate and is influenced by several factors. Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a member of the EGF family of growth factors and is synthesized as a membrane-associated precursor molecule (proHB-EGF). Under stressful conditions proHB-EGF is proteolytically cleaved and released as a soluble ligand (sHB-EGF) that activates the EGF receptor. We show that antibody against CD9, a membrane tetraspanin, induces apoptosis in mouse embryonic stem cells through the activation of specific EGF receptor residues (Y-1148 and Y-1173), caspase-3 and MAPK signalling. HB-EGF and the p38 inhibitor PD169316 act in a pro-survival manner by perturbing phosphorylation of EGFR Y-1173, suggesting its importance in inducing apoptosis. Caspase-3 activation was attenuated in the presence of HB-EGF and PD169316. Furthermore, HB-EGF and PD169316 prevent p38 phosphorylation while promoting the phosphorylation of the pro-survival SAPK/JNK and ERK. These results suggest a role for CD9 as an endogenous suppressor of apoptosis, an effect that is mimicked by HB-EGF and PD169316. PMID:19010935

  15. Synergistic Action of Fibroblast Growth Factor-2 and Transforming Growth Factor-beta1 Enhances Bioprinted Human Neocartilage Formation

    PubMed Central

    Cui, Xiaofeng; Breitenkamp, Kurt; Lotz, Martin; D’Lima, Darryl

    2012-01-01

    Bioprinting as a promising but unexplored approach for cartilage tissue engineering has the advantages of high throughput, digital control, and highly accurate placement of cells and biomaterial scaffold to the targeted 3D locations with simultaneous polymerization. This study tested feasibility of using bioprinting for cartilage engineering and examined the influence of cell density, growth and differentiation factors. Human articular chondrocytes were printed at various densities, stimulated transiently with growth factors and subsequently with chondrogenic factors. Samples were cultured for up to 4 weeks to evaluate cell proliferation and viability, mechanical properties, mass swelling ratio, water content, gene expression, ECM production, DNA content, and histology. Bioprinted samples treated with FGF-2/TGF-?1 had the best chondrogenic properties among all groups apparently due to synergistic stimulation of cell proliferation and chondrogenic phenotype. ECM production per chondrocyte in low cell density was much higher than that in high cell seeding density. This finding was also verified by mechanical testing and histology. In conclusion, cell seeding density that is feasible for bioprinting also appears optimal for human neocartilage formation when combined with appropriate growth and differentiation factors. PMID:22508498

  16. Vascular endothelial growth factor, platelet-derived endothelial cell growth factor and angiogenesis in non-small-cell lung cancer

    PubMed Central

    O'Byrne, K J; Koukourakis, M I; Giatromanolaki, A; Cox, G; Turley, H; Steward, W P; Gatter, K; Harris, A L

    2000-01-01

    High microvessel density, an indirect measure of angiogenesis, has been shown to correlate with increased tumour size, lymph node involvement and poor prognosis in non-small-cell lung cancer (NSCLC). Tumour cell vascular endothelial growth factor (VEGF) and platelet-derived endothelial cell growth factor (PD-ECGF) expression correlate with angiogenesis and a poor outcome in this disease. In a retrospective study VEGF and PD-ECGF expression and microvessel density were evaluated immunohistochemically in surgically resected specimens (T1–3, N0–2) from 223 patients with operable NSCLC using the VG1, P-GF.44C and JC70 monoclonal antibodies respectively. High VEGF immunoreactivity was seen in 104 (46.6%) and PD-ECGF in 72 (32.3%) cases and both were associated with high vascular grade tumours (P = 0.009 and P = 0.05 respectively). Linear regression analysis revealed a weak positive correlation between VEGF and PD-ECGF expression in cancer cells (r = 0.21;P = 0.002). Co-expression of VEGF and PD-ECGF was not associated with a higher microvessel density than VEGF or PD-ECGF only expressing tumours. Furthermore a proportion of high vascular grade tumours expressed neither growth factor. Univariate analysis revealed tumour size, nodal status, microvessel density and VEGF and PD-ECGF expression as significant prognostic factors. Tumour size (P< 0.02) and microvessel density (P< 0.04) remained significant on multivariate analysis. In conclusion, VEGF and PD-ECGF are important angiogenic growth factors and have prognostic significance in NSCLC. Furthermore the study underlines the prognostic significance of microvessel density in operable NSCLC. © 2000 Cancer Research Campaign PMID:10780522

  17. Growth factor deprivation induces cytosolic translocation of SIRT1

    NASA Astrophysics Data System (ADS)

    Meng, Chengbo; Xing, Da; Wu, Shengnan; Huang, Lei

    2010-02-01

    Sirtuin type 1 (SIRT1), a NAD+-dependent histone deacetylases, plays a critical role in cellular senescence, aging and longevity. In general, SIRT1 is localized in nucleus and is believed as a nuclear protein. Though overexpression of SIRT1 delays senescence, SIRT1-protein levels decline naturally in thymus and heart during aging. In the present studies, we investigated the subcellular localization of SIRT1 in response to growth factor deprivation in African green monkey SV40-transformed kidney fibroblast cells (COS-7). Using SIRT1-EGFP fluorescence reporter, we found that SIRT1 localized to nucleus in physiological conditions. We devised a model enabling cell senescence via growth factor deprivation, and we found that SIRT1 partially translocated to cytosol under the treatment, suggesting a reduced level of SIRT1's activity. We found PI3K/Akt pathway was involved in the inhibition of SIRT1's cytosolic translocation, because inhibition of these kinases significantly decreased the amount of SIRT1 maintained in nucleus. Taken together, we demonstrated that growth factor deprivation induces cytosolic translocation of SIRT1, which suggesting a possible connection between cytoplasm-localized SIRT1 and the aging process.

  18. KLF10, transforming growth factor-{beta}-inducible early gene 1, acts as a tumor suppressor

    SciTech Connect

    Song, Ki-Duk [Center for Agricultural Biomaterials, Seoul National University, Seoul 151-921 (Korea, Republic of) [Center for Agricultural Biomaterials, Seoul National University, Seoul 151-921 (Korea, Republic of); Laboratory of Protein Engineering and Comparative Immunology, School of Agricultural Biotechnology, Seoul National University, Seoul 151-921 (Korea, Republic of); Kim, Duk-Jung [The Institute of Hankook Life Science, 7-9 Myungryun-dong, Jongno-gu, Seoul 110-521 (Korea, Republic of)] [The Institute of Hankook Life Science, 7-9 Myungryun-dong, Jongno-gu, Seoul 110-521 (Korea, Republic of); Lee, Jong Eun [Department of Anatomy, College of Medicine, Yonsei University, Seoul 120-752 (Korea, Republic of)] [Department of Anatomy, College of Medicine, Yonsei University, Seoul 120-752 (Korea, Republic of); Yun, Cheol-Heui [Center for Agricultural Biomaterials, Seoul National University, Seoul 151-921 (Korea, Republic of) [Center for Agricultural Biomaterials, Seoul National University, Seoul 151-921 (Korea, Republic of); Laboratory of Protein Engineering and Comparative Immunology, School of Agricultural Biotechnology, Seoul National University, Seoul 151-921 (Korea, Republic of); Lee, Woon Kyu, E-mail: wklee@inha.ac.kr [Laboratory of Developmental Genetics, School of Medicine, Inha University, Incheon 400-712 (Korea, Republic of); Brain Korea 21 Center for Advanced Medical Education, School of Medicine, Inha University, Incheon 400-712 (Korea, Republic of)

    2012-03-09

    Highlights: Black-Right-Pointing-Pointer KLF10{sup -/-} mice exhibited accelerated papilloma development after DMBA/TPA treatment. Black-Right-Pointing-Pointer KLF10{sup -/-} keratinocytes showed increased proliferation and apoptosis. Black-Right-Pointing-Pointer KLF10{sup -/-} MEFs yielded more colonies than wild-type one with H-Ras transfection. Black-Right-Pointing-Pointer KLF10 dose-dependently activated p21{sup WAF1/CIP1} transcription. Black-Right-Pointing-Pointer KLF10 is a tumor suppressor and that it targets p21{sup WAF1/CIP1} transcription. -- Abstract: Krueppel-like factor 10 (KLF10) has been suggested to be a putative tumor suppressor. In the present study, we generated KLF10 deficient mice to explore this hypothesis in vivo. KLF10 deficient mice exhibited increased predisposition to skin tumorigenesis and markedly accelerated papilloma development after DMBA/TPA treatment. On the other hand, KLF10 deficient keratinocytes showed increased proliferation and apoptosis. In colony formation assays after oncogenic H-Ras transfection, KLF10 deficient mouse embryonic fibroblasts (MEFs) yielded more colonies than wild-type MEFs. Furthermore, KLF10 dose-dependently activated p21{sup WAF1/CIP1} transcription, which was independent of p53 and Sp1 binding sites in p21{sup WAF1/CIP1} promoter. This study demonstrates that KLF10 is a tumor suppressor and that it targets p21{sup WAF1/CIP1} transcription.

  19. Malignant Transformation of Mouse Primary Keratinocytes by Harvey Sarcoma Virus and Its Modulation by Surrounding Normal Cells

    NASA Astrophysics Data System (ADS)

    Dotto, Gian Paolo; Weinberg, Robert A.; Ariza, Aurelio

    1988-09-01

    The activated ras oncogene that is present in Harvey sarcoma virus is able to induce malignant transformation of pure cultures of mouse primary keratinocytes. Malignant transformation of these cells is demonstrated by their ability to form carcinomas when grafted back onto syngeneic animals. However, expression of the malignant phenotype by the ras-transformed keratinocytes is drastically inhibited by the presence of normal dermal fibroblasts. This inhibitory effect depends on the ratio of fibroblasts to keratinocytes. It can be observed with mitomycin C-treated growth-arrested dermal fibroblasts and not with other cells, such as normal keratinocytes or established fibroblasts. Thus, a cellular environment approximating normal tissue can suppress tumor formation triggered by a single oncogene.

  20. Human Papilloma Viral DNA Replicates as a Stable Episome in Cultured Epidermal Keratinocytes

    NASA Astrophysics Data System (ADS)

    Laporta, Robert F.; Taichman, Lorne B.

    1982-06-01

    Human papilloma virus (HPV) is poorly understood because systems for its growth in tissue culture have not been developed. We report here that cultured human epidermal keratinocytes could be infected with HPV from plantar warts and that the viral DNA persisted and replicated as a stable episome. There were 50-200 copies of viral DNA per cell and there was no evidence to indicate integration of viral DNA into the cellular genome. There was also no evidence to suggest that viral DNA underwent productive replication. We conclude that cultured human epidermal keratinocytes may be a model for the study of certain aspects of HPV biology.

  1. Growth differentiation factor 11 signals through the transforming growth factor-b receptor ALK5 to

    E-print Network

    Ibáñez, Carlos

    differentiation factor 11 (GDF11) contributes to regio- nalize the mouse embryo along its anterior­posterior axis by regulating the expression of Hox genes. The identity of the receptors that mediate GDF11 signalling during embryogenesis remains unclear. Here, we show that GDF11 can interact with type I receptors ALK4, ALK5 and ALK7

  2. Enhancement of intestinal growth in neonatal rats by epidermal growth factor in milk

    SciTech Connect

    Berseth, C.L. (Mayo Clinic and Mayo Foundation, Rochester, MN (USA))

    1987-11-01

    Breast milk has been shown to enhance neonatal intestinal growth. Because epidermal growth factor (EGF) is present in the milk of various mammalian species, the hypothesis was tested that EGF in rodent milk mediates, in part, the breast milk-enhanced intestinal growth in neonatal rat. Fifty-eight rat pups fed artificial formal that contained 1.2, 3.0, and 6.0 {mu}g/ml EGF for 39 h had greater incorporation of ({sup 3}H)thymidine into DNA and DNA content of intestine than 29 pups fed unsupplemented formula. Pups fed EGF for 5 days had significantly greater body weight, intestinal weight, length, and DNA content than control pups. Conversely, pups fed pooled rat milk containing rabbit-derived antibody to EGF for 39 h had intestines of lower weight that contained less DNA than animals fed rat milk containing normal rabbit serum. EGF appears to mediate, in part, breast milk-enhanced neonatal intestinal growth.

  3. Effects of epidermal growth factor on the growth of human gastric cancer cell and the implanted tumor of nude mice

    Microsoft Academic Search

    Lu Xia; Yao-Zong Yuan; Chun-Di Xu; Yong-Pin Zhang; Ming-Ming Qiao; Jia-Xu Xu

    AIM: Epidermal growth factor (EGF) plays an important role in the regulation of gastrointestinal tissue growth and development, and it can stimulate epithelial proliferation, cell differentiation and growth. It has been established that the EGF can promote gastric cytoprotection and ulcer healing. But the potential ability of EGF to regulate the gastric cancer growth is unknown. This study is to

  4. The GEF Bcr activates RhoA/MAL signaling to promote keratinocyte differentiation via desmoglein-1

    PubMed Central

    Dubash, Adi D.; Koetsier, Jennifer L.; Amargo, Evangeline V.; Najor, Nicole A.; Harmon, Robert M.

    2013-01-01

    Although much is known about signaling factors downstream of Rho GTPases that contribute to epidermal differentiation, little is known about which upstream regulatory proteins (guanine nucleotide exchange factors [GEFs] or GTPase-activating proteins [GAPs]) are involved in coordinating Rho signaling in keratinocytes. Here we identify the GEF breakpoint cluster region (Bcr) as a major upstream regulator of RhoA activity, stress fibers, and focal adhesion formation in keratinocytes. Loss of Bcr reduced expression of multiple markers of differentiation (such as desmoglein-1 [Dsg1], keratin-1, and loricrin) and abrogated MAL/SRF signaling in differentiating keratinocytes. We further demonstrated that loss of Bcr or MAL reduced levels of Dsg1 mRNA in keratinocytes, and ectopic expression of Dsg1 rescued defects in differentiation seen upon loss of Bcr or MAL signaling. Taken together, these data identify the GEF Bcr as a regulator of RhoA/MAL signaling in keratinocytes, which in turn promotes differentiation through the desmosomal cadherin Dsg1. PMID:23940119

  5. Production of Superoxide Anions by Keratinocytes Initiates P. acnes-Induced Inflammation of the Skin

    PubMed Central

    Grange, Philippe A.; Chéreau, Christiane; Raingeaud, Joël; Nicco, Carole; Weill, Bernard

    2009-01-01

    Acne vulgaris is a chronic inflammatory disorder of the sebaceous follicles. Propionibacterium acnes (P. acnes), a gram-positive anareobic bacterium, plays a critical role in the development of these inflammatory lesions. This study aimed at determining whether reactive oxygen species (ROS) are produced by keratinocytes upon P. acnes infection, dissecting the mechanism of this production, and investigating how this phenomenon integrates in the general inflammatory response induced by P. acnes. In our hands, ROS, and especially superoxide anions (O2•?), were rapidly produced by keratinocytes upon stimulation by P. acnes surface proteins. In P. acnes-stimulated keratinocytes, O2•? was produced by NAD(P)H oxidase through activation of the scavenger receptor CD36. O2•? was dismuted by superoxide dismutase to form hydrogen peroxide which was further detoxified into water by the GSH/GPx system. In addition, P. acnes-induced O2•? abrogated P. acnes growth and was involved in keratinocyte lysis through the combination of O2•? with nitric oxide to form peroxynitrites. Finally, retinoic acid derivates, the most efficient anti-acneic drugs, prevent O2•? production, IL-8 release and keratinocyte apoptosis, suggesting the relevance of this pathway in humans. PMID:19629174

  6. Activation of TLR3 in keratinocytes increases expression of genes involved in formation of the epidermis, lipid accumulation and epidermal organelles

    PubMed Central

    Borkowski, Andrew W.; Park, Kyungho; Uchida, Yoshikazu; Gallo, Richard L.

    2013-01-01

    Injury to the skin, and the subsequent release of non-coding double-stranded RNA from necrotic keratinocytes, has been identified as an endogenous activator of Toll-like receptor 3 (TLR3). Since changes in keratinocyte growth and differentiation follow injury, we hypothesized that TLR3 might trigger some elements of the barrier repair program in keratinocytes. Double-stranded RNA was observed to induce TLR3-dependent increases in human keratinocyte mRNA abundance for ABCA12 (ATP-binding cassette, sub-family A, member 12), glucocerebrosidase, acid sphingomyelinase, and transglutaminase 1. Additionally, treatment with double-stranded RNA resulted in increases in sphingomyelin and morphologic changes including increased epidermal lipid staining by oil-red O and TLR3-dependent increases in lamellar bodies and keratohyalin granules. These observations show that double-stranded RNA can stimulate some events in keratinocytes that are important for skin barrier repair and maintenance. PMID:23353987

  7. Regulation of vascular endothelial growth factor-dependent retinal neovascularization by insulin-like growth factor-1 receptor.

    PubMed

    Smith, L E; Shen, W; Perruzzi, C; Soker, S; Kinose, F; Xu, X; Robinson, G; Driver, S; Bischoff, J; Zhang, B; Schaeffer, J M; Senger, D R

    1999-12-01

    Although insulin-like growth factor 1 (IGF-1) has been associated with retinopathy, proof of a direct relationship has been lacking. Here we show that an IGF-1 receptor antagonist suppresses retinal neovascularization in vivo, and infer that interactions between IGF-1 and the IGF-1 receptor are necessary for induction of maximal neovascularization by vascular endothelial growth factor (VEGF). IGF-1 receptor regulation of VEGF action is mediated at least in part through control of VEGF activation of p44/42 mitogen-activated protein kinase, establishing a hierarchical relationship between IGF-1 and VEGF receptors. These findings establish an essential role for IGF-1 in angiogenesis and demonstrate a new target for control of retinopathy. They also explain why diabetic retinopathy initially increases with the onset of insulin treatment. IGF-1 levels, low in untreated diabetes, rise with insulin therapy, permitting VEGF-induced retinopathy. PMID:10581081

  8. C\\/EBP  Is a DNA Damage-Inducible p53-Regulated Mediator of the G1 Checkpoint in Keratinocytes

    Microsoft Academic Search

    Kyungsil Yoon; Robert C. Smart

    2004-01-01

    The basic leucine zipper transcription factor, CCAAT\\/enhancer binding protein (C\\/EBP), is abundantly expressed in keratinocytes of the skin; however, its function in skin is poorly characterized. UVB radiation is responsible for the majority of human skin cancers. In response to UVB-induced DNA damage, keratinocytes activate cell cycle checkpoints that arrest cell cycle progression and prevent replication of damaged DNA, allowing

  9. Differentiation of Human Induced Pluripotent Stem Cells into a Keratinocyte Lineage

    PubMed Central

    Kogut, Igor; Roop, Dennis R.; Bilousova, Ganna

    2014-01-01

    Direct reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) provides an opportunity to develop novel personalized treatment options for numerous diseases and to advance current approaches for cell-based drug discoveries and disease modeling. The ability to differentiate iPSCs into relevant cell types is an important prerequisite for the successful development of iPSC-based treatment and modeling strategies. Here, we describe a protocol for the efficient differentiation of human iPSCs into functional keratinocytes. The protocol employs treating iPSCs with retinoic acid and bone-morphogenetic protein-4 to induce differentiation toward a keratinocyte lineage, which is then followed by the growth of differentiated iPSCs on collagen type I- and collagen type IV-coated dishes to enrich for iPSC-derived keratinocytes. PMID:24510784

  10. Perinuclear localization of the protein-tyrosine phosphatase SHP-1 and inhibition of epidermal growth factor-stimulated STAT1/3 activation in A431 cells.

    PubMed

    Tenev, T; Böhmer, S A; Kaufmann, R; Frese, S; Bittorf, T; Beckers, T; Böhmer, F D

    2000-04-01

    The SH2 domain protein-tyrosine phosphatase SHP-1 has been shown earlier to bind to the epidermal growth factor receptor and to have the capacity for receptor dephosphorylation. New bi- and tricistronic expression vectors (pNRTIS-21 and pNRTIS-33, respectively) based on the tetracycline system were constructed and employed to generate stable cell lines with inducible expression of SHP-1. Inducible overexpression of SHP-1 in A431 cells led to attenuation of epidermal growth factor (EGF) receptor autophosphorylation and of EGF-induced DNA binding of 'signal transducers and activators of transcription' (STAT) 1 and 3. SHP-1 was localized in the cytoplasm with an enrichment in the perinuclear compartment. Association of SHP-1 with perinuclear structures may form the basis for a partial cofractionation with nuclei observed in different types of transfected cells and also with endogenous SHP-1 in U-937 cells. Treatment of SHP-1-overexpressing A431 cells or of HaCaT human keratinocytes expressing SHP-1 endogenously with the Ca2+-ionophore A23187 resulted in partial nuclear accumulation of SHP-1. Thus, SHP-1 may interact with substrates or regulatory proteins in perinuclear or nuclear structures. PMID:10826494

  11. Placenta Growth Factor Overexpression Inhibits Tumor Growth, Angiogenesis, and Metastasis by Depleting Vascular Endothelial Growth Factor Homodimers in Orthotopic Mouse Models

    Microsoft Academic Search

    Lei Xu; David M. Cochran; Ricky T. Tong; Frank Winkler; Satoshi Kashiwagi; Rakesh K. Jain; Dai Fukumura

    The role of placenta growth factor (PlGF) in pathologic angiogenesis is controversial. The effects of PlGF on growth, angiogenesis, and metastasis from orthotopic tumors are not known. To this end, we stably transfected three human cancer cell lines (A549 lung, HCT116 colon, and U87-MG glioblasto- ma) with human plgf-2 full-length cDNA. Overexpression of PlGF did not affect tumor cell proliferation

  12. Vascular Permeability Factor\\/Vascular Endothelial Growth Factor Induces Lymphangiogenesis as well as Angiogenesis

    Microsoft Academic Search

    Janice A. Nagy; Eliza Vasile; Dian Feng; Christian Sundberg; Lawrence F. Brown; Michael J. Detmar; Joel A. Lawitts; Laura Benjamin; Xiaolian Tan; Eleanor J. Manseau; Ann M. Dvorak; Harold F. Dvorak

    2002-01-01

    Vascular permeability factor\\/vascular endothelial growth factor (VPF\\/VEGF, VEGF-A) is a multifunctional cytokine with important roles in pathological angiogenesis. Using an adeno- viral vector engineered to express murine VEGF-A 164 , we previously investigated the steps and mechanisms by which this cytokine induced the formation of new blood vessels in adult immu- nodeficient mice and demonstrated that the newly formed blood

  13. Placental defect and embryonic lethality in mice lacking hepatocyte growth factor\\/scatter factor

    Microsoft Academic Search

    Yoshihiko Uehara; Osamu Minowa; Chisato Mori; Kohei Shiota; Junko Kuno; Tetsuo Noda; Naomi Kitamura

    1995-01-01

    HEPATOCYTE growth factor\\/scatter factor (HGF\\/SF) functions as a mitogen, motogen and morphogen for a variety of cultured cells1-7. The genes for HGF\\/SF and its receptor (the c-met protooncogene product8) are expressed in many tissues during the embryonic periods and in the adult9-14. HGF\\/SF is thought to mediate a signal exchange between the mesenchyme and epithelia during mouse development15. To examine

  14. Maternal parity, fetal and childhood growth, and cardiometabolic risk factors.

    PubMed

    Gaillard, Romy; Rurangirwa, Akashi A; Williams, Michelle A; Hofman, Albert; Mackenbach, Johan P; Franco, Oscar H; Steegers, Eric A P; Jaddoe, Vincent W V

    2014-08-01

    We examined the associations of maternal parity with fetal and childhood growth characteristics and childhood cardiometabolic risk factors in a population-based prospective cohort study among 9031 mothers and their children. Fetal and childhood growth were repeatedly measured. We measured childhood anthropometrics, body fat distribution, left ventricular mass, blood pressure, blood lipids, and insulin levels at the age of 6 years. Compared with nulliparous mothers, multiparous mothers had children with higher third trimester fetal head circumference, length and weight growth, and lower risks of preterm birth and small-size-for-gestational-age at birth but a higher risk of large-size-for-gestational-age at birth (P<0.05). Children from multiparous mothers had lower rates of accelerated infant growth and lower levels of childhood body mass index, total fat mass percentage, and total and low-density lipoprotein cholesterol than children of nulliparous mothers (P<0.05). They also had a lower risk of childhood overweight (odds ratio, 0.75 [95% confidence interval, 0.63–0.88]). The risk of childhood clustering of cardiometabolic risk factors was not statistically significantly different (odds ratio, 0.82; 95% confidence interval, 0.64–1.05). Among children from multiparous mothers only, we observed consistent trends toward a lower risk of childhood overweight and lower cholesterol levels with increasing parity (P<0.05). In conclusion, offspring from nulliparous mothers have lower fetal but higher infant growth rates and higher risks of childhood overweight and adverse metabolic profile. Maternal nulliparity may have persistent cardiometabolic consequences for the offspring. PMID:24866145

  15. Human oocyte maturation is dependent on LH-stimulated accumulation of the epidermal growth factor-like growth factor, amphiregulin†

    PubMed Central

    Zamah, A.M.; Hsieh, M.; Chen, J.; Vigne, J.L.; Rosen, M.P.; Cedars, M.I.; Conti, M.

    2010-01-01

    BACKGROUND The LH surge promotes ovulation via activation of multiple signaling networks in the ovarian follicle. Studies in animal models have shown the importance of LH-induced activation of the epidermal growth factor (EGF)signaling network in critical peri-ovulatory events. We investigated the biological significance of regulatory mechanisms mediated by EGF-like growth factors during LH stimulation in humans. METHODS We characterized the EGF signaling network in mature human ovarian follicles using in vivo and in vitro approaches. Amphiregulin (AREG) levels were measured in 119 follicular fluid (FF) samples from IVF/ICSI patients. Biological activity of human FF was assessed using in vitro oocyte maturation, cumulus expansion and cell mitogenic assays. RESULTS AREG is the most abundant EGF-like growth factor accumulating in the FF of mature follicles of hCG-stimulated patients. No AREG was detected before the LH surge or before hCG stimulation of granulosa cells in vitro, demonstrating that the accumulation of AREG requires gonadotrophin stimulation. Epiregulin and betacellulin mRNA were detected in both human mural and cumulus granulosa cells, although at significantly lower levels than AREG. FF from stimulated follicles causes cumulus expansion and oocyte maturation in a reconstitution assay. Immunodepletion of AREG abolishes the ability of FF to stimulate expansion (P < 0.0001) and oocyte maturation (P < 0.05), confirming the biological activity of AREG. Conversely, mitogenic activity of FF remained after depletion of AREG, indicating that other mitogens accumulate in FF. FF from follicles yielding an immature germinal vesicle oocyte or from an oocyte that develops into an aberrant embryo contains lower AREG levels than that from follicles yielding a healthy oocyte (P = 0.008). CONCLUSIONS EGF-like growth factors play a role in critical peri-ovulatory events in humans, and AREG accumulation is a useful marker of gonadotrophin stimulation and oocyte competence. PMID:20719813

  16. Growth differentiation factor 11 signals through the transforming growth factor-? receptor ALK5 to regionalize the anterior–posterior axis

    Microsoft Academic Search

    Olov Andersson; Eva Reissmann; Carlos F. Ibanez

    2006-01-01

    Growth differentiation factor 11 (GDF11) contributes to regionalize the mouse embryo along its anterior–posterior axis by regulating the expression of Hox genes. The identity of the receptors that mediate GDF11 signalling during embryogenesis remains unclear. Here, we show that GDF11 can interact with type I receptors ALK4, ALK5 and ALK7, but predominantly uses ALK4 and ALK5 to activate a Smad3-dependent

  17. New Therapeutic Directions for Advanced Pancreatic Cancer: Targeting the Epidermal Growth Factor and Vascular Endothelial Growth Factor Pathways

    Microsoft Academic Search

    HOWARD BURRIS; CAIO ROCHA-LIMAb

    In advanced pancreatic cancer, single-agent gemci- tabine became the standard therapy approximately 10 years ago. Subsequently, combinations of gemcita- bine with fluorouracil, cisplatin, irinotecan, oxalipla- tin, or pemetrexed produced no clear survival benefit. Among the newer approaches, targeting human epi- dermal growth factor receptor (HER-1\\/EGFR) shows promise. The U.S. Food and Drug Administration re- cently approved erlotinib (a HER-1\\/EGFR tyrosine

  18. Proteome profiling of keratinocytes transforming to malignancy.

    PubMed

    Paulitschke, Verena; Gerner, Christopher; Hofstätter, Elisabeth; Mohr, Thomas; Mayer, Rupert Laurenz; Pehamberger, Hubert; Kunstfeld, Rainer

    2015-02-01

    To shed light on the multistep process of squamous cell carcinoma development and the underlying pathologic mechanisms, we performed comparative proteome analysis of keratinocytes, keratinocytes stimulated with Il-1beta, and A431 epidermoid carcinoma cells. Fractionation of the cells into supernatant, nucleus, and cytoplasm was followed by protein separation, proteolytic digest, and nano-LC separation, and fragmentation using an ion trap mass spectrometer. Specific bioinformatics tools were used to generate a list of keratinocyte-specific proteins. Ninety percent of these proteins were found to be upregulated in keratinocytes versus the A431 cells. Classification of the identified proteins by biologic function and gene set enrichment analysis revealed that keratinocytes produced more proteins involved in cell differentiation, cell adhesion, cell junction, calcium ion, calmodulin binding, cytoskeleton organization, and cytokinesis, whereas A431 produced more proteins involved in cell cycle checkpoint, cell cycle process, RNA processing and transport, DNA damage and repair, RNA and DNA binding, and chromatin remodeling. The protein signatures of A431 and normal keratinocytes treated with IL-1beta showed marked similarity, confirming that inflammation is an important step in malignant transformation in nonmelanoma skin cancer. Thus, proteome profiling and bioinformatic processing may support the understanding of the underlying mechanisms, with the potential to facilitate development of early biomarkers and patient-tailored therapy. PMID:25395074

  19. An Expandable, Inducible Hemangioblast State Regulated by Fibroblast Growth Factor

    PubMed Central

    Vereide, David T.; Vickerman, Vernella; Swanson, Scott A.; Chu, Li-Fang; McIntosh, Brian E.; Thomson, James A.

    2014-01-01

    Summary During development, the hematopoietic and vascular lineages are thought to descend from common mesodermal progenitors called hemangioblasts. Here we identify six transcription factors, Gata2, Lmo2, Mycn, Pitx2, Sox17, and Tal1, that “trap” murine cells in a proliferative state and endow them with a hemangioblast potential. These “expandable” hemangioblasts (eHBs) are capable, once released from the control of the ectopic factors, to give rise to functional endothelial cells, multilineage hematopoietic cells, and smooth muscle cells. The eHBs can be derived from embryonic stem cells, from fetal liver cells, or poorly from fibroblasts. The eHBs reveal a central role for fibroblast growth factor, which not only promotes their expansion, but also facilitates their ability to give rise to endothelial cells and leukocytes, but not erythrocytes. This study serves as a demonstration that ephemeral progenitor states can be harnessed in vitro, enabling the creation of tractable progenitor cell lines. PMID:25458896

  20. Activation of BAD by therapeutic inhibition of epidermal growth factor receptor and transactivation by insulin-like growth factor receptor.

    PubMed

    Gilmore, Andrew P; Valentijn, Anthony J; Wang, Pengbo; Ranger, Ann M; Bundred, Nigel; O'Hare, Michael J; Wakeling, Alan; Korsmeyer, Stanley J; Streuli, Charles H

    2002-08-01

    Novel cancer chemotherapeutics are required to induce apoptosis by activating pro-apoptotic proteins. Both epidermal growth factor (EGF) and insulin-like growth factor (IGF) provide potent survival stimuli in many epithelia, and activation of their receptors is commonly observed in solid human tumors. Here we demonstrate that blockade of the EGF receptor by a new drug in phase III clinical trails for cancer, ZD1839, potently induces apoptosis in mammary epithelial cell lines and primary cultures, as well as in a primary pleural effusion from a breast cancer patient. We identified the mechanism of apoptosis induction by ZD1839. We showed that it prevents cell survival by activating the pro-apoptotic protein BAD. Moreover, we demonstrate that IGF transactivates the EGF receptor and that ZD1839 blocks IGF-mediated phosphorylation of MAPK and BAD. Many cancer therapies kill tumor cells by inducing apoptosis as a consequence of targeting DNA; however, the threshold at which apoptosis can be triggered through DNA damage is often different from that in normal cells. Our results indicate that by targeting a growth factor-mediated survival signaling pathway, BAD phosphorylation can be manipulated therapeutically to induce apoptosis. PMID:12011069

  1. Growth and differentiation in cultured human thyroid cells: effects of epidermal growth factor and thyrotropin.

    PubMed

    Errick, J E; Ing, K W; Eggo, M C; Burrow, G N

    1986-01-01

    Human thyroid cells were grown and subcultured in vitro to examine their responses to known hormones and growth factors, and to serum. The cells were obtained from surgical specimens and were either neoplastic or nonneoplastic. The effects of culture conditions on cell growth were measured by changes in cell numbers and by stimulation of [3H]thymidine incorporation. The results showed that serum (0.5%) was essential for cell proliferation, and that a mixture of insulin (10 micrograms/ml), transferrin (5 micrograms/ml), hydrocortisone (10 micrograms/ml), somatostatin (10 ng/ml), and glycyl-histidyl-lysine (10 ng/ml) enhanced the effect of serum. Maximum growth of the cells was obtained when epidermal growth factor was present at 10(-9) M. Differentiation was measured by production of thyroglobulin, which was found to be stimulated by thyrotropin. This system provides a means to study the hormonal control of growth and differentiation in human thyroid cells. PMID:3511027

  2. Basic fibroblast growth factor promotes macaque follicle development in vitro.

    PubMed

    Lu, C L; Yan, J; Zhi, X; Xia, X; Wang, T R; Yan, L Y; Yu, Y; Ding, T; Gao, J M; Li, R; Qiao, J

    2015-05-01

    Fertility preservation is an important type of frontier scientific research in the field of reproductive health. The culture of ovarian cortices to i) initiate primordial follicle growth and ii) procure developing follicles for later oocyte maturation is a promising fertility preservation strategy, especially for older women or cancer patients. At present, this goal remains largely unsubstantiated in primates because of the difficulty in attaining relatively large follicles via ovarian cortex culture. To overcome this hurdle, we cultured macaque monkey ovarian cortices with FSH, kit ligand (KL), basic fibroblast growth factor (bFGF), and/or epidermal growth factor (EGF). The various factors and factor combinations promoted primordial follicle development to different extents. Notably, both bFF (bFGF, 100 ng/ml and FSH, 50 ng/ml) and KF (KL, 100 ng/ml and FSH, 50 ng/ml) contributed to the activation of primordial follicles at day 12 (D12) of culture, whereas at D18, the proportions of developing follicles were significantly higher in the bFF and KF groups relative to the other treatment groups, particularly in the bFF group. Estradiol and progesterone production were also highest in the bFF group, and primary follicle diameters were the largest. Up until D24, the bFF group still exhibited the highest proportion of developing follicles. In conclusion, the bFGF-FSH combination promotes nonhuman primate primordial follicle development in vitro, with the optimal experimental window within 18 days. These results provide evidence for the future success of human ovarian cortex culture and the eventual acquisition of mature human follicles or oocytes for fertility restoration. PMID:25687412

  3. Expression of insulin-like growth factor-1 in uremic rats: Growth hormone resistance and nutritional intake

    Microsoft Academic Search

    Winnie Chan; Kristoffer C Valerie; James C M Chan

    1993-01-01

    Expression of insulin-like growth factor-1 in uremic rats: Growth hormone resistance and nutritional intake. This study was designed to test the hypothesis that induction of insulin-like growth factor-1 (IGF-1) is reduced in the uremic rat liver, which would help to explain the purported growth hormone resistance noted in uremia. IGF-1 mRNA, in the steady state and after acute induction by

  4. Regulation of mTOR complex 1 in response to growth factors and nutrients

    E-print Network

    Sancak, Yasemin S. (Yasemin Shechner)

    2010-01-01

    In multicellular organisms, cells ensure the simultaneous availability of growth factors and nutrients before they invest in cellular processes that lead to growth. The TOR kinase is a master regulator of cellular growth ...

  5. Fibroblast growth factor (FGF) signaling in development and skeletal diseases

    PubMed Central

    Teven, Chad M.; Farina, Evan M.; Rivas, Jane; Reid, Russell R.

    2014-01-01

    Fibroblast growth factors (FGF) and their receptors serve many functions in both the developing and adult organism. Humans contain 18 FGF ligands and four FGF receptors (FGFR). FGF ligands are polypeptide growth factors that regulate several developmental processes including cellular proliferation, differentiation, and migration, morphogenesis, and patterning. FGF-FGFR signaling is also critical to the developing axial and craniofacial skeleton. In particular, the signaling cascade has been implicated in intramembranous ossification of cranial bones as well as cranial suture homeostasis. In the adult, FGFs and FGFRs are crucial for tissue repair. FGF signaling generally follows one of three transduction pathways: RAS/MAP kinase, PI3/AKT, or PLC?. Each pathway likely regulates specific cellular behaviors. Inappropriate expression of FGF and improper activation of FGFRs are associated with various pathologic conditions, unregulated cell growth, and tumorigenesis. Additionally, aberrant signaling has been implicated in many skeletal abnormalities including achondroplasia and craniosynostosis. The biology and mechanisms of the FGF family have been the subject of significant research over the past 30 years. Recently, work has focused on the therapeutic targeting and potential of FGF ligands and their associated receptors. The majority of FGF-related therapy is aimed at age-related disorders. Increased understanding of FGF signaling and biology may reveal additional therapeutic roles, both in utero and postnatally. This review discusses the role of FGF signaling in general physiologic and pathologic embryogenesis and further explores it within the context of skeletal development. PMID:25679016

  6. Epidermal growth factor or transforming growth factor alpha is required for kidney tubulogenesis in matrigel cultures in serum-free medium.

    PubMed Central

    Taub, M; Wang, Y; Szczesny, T M; Kleinman, H K

    1990-01-01

    The ability of matrigel, a reconstituted basement membrane gel, to induce the differentiation of baby mouse kidney cells has been examined in a hormonally defined serum-free medium. Primary cultures of baby mouse kidney cells were observed to form tubules over a time interval of 1-2 weeks in matrigel. Electron microscopic studies showed that tubules with lumens were present, and the tubule morphology was similar to that of the collecting duct. When using matrigel from which the growth factors had been removed, tubule formation no longer occurred, unless the medium was further supplemented with epidermal growth factor (10 ng/ml). Transforming growth factor alpha stimulated tubule formation as effectively as epidermal growth factor, whereas transforming growth factor beta had an inhibitory effect on tubule formation. These data suggest that both an extracellular matrix and specific growth factors may regulate kidney differentiation during development. Images PMID:2339133

  7. Platelet-derived growth factor-a receptor activation is required for human cytomegalovirus infection

    E-print Network

    Cai, Long

    LETTERS Platelet-derived growth factor-a receptor activation is required for human cytomegalovirus understood4 . Here we show that platelet-derived growth factor-a receptor (PDGFR-a) is specif- ically

  8. Extracellular vimentin interacts with insulin-like growth factor 1 receptor to promote axonal growth

    PubMed Central

    Shigyo, Michiko; Kuboyama, Tomoharu; Sawai, Yusuke; Tada-Umezaki, Masahito; Tohda, Chihiro

    2015-01-01

    Vimentin, an intermediate filament protein, is generally recognised as an intracellular protein. Previously, we reported that vimentin was secreted from astrocytes and promoted axonal growth. The effect of extracellular vimentin in neurons was a new finding, but its signalling pathway was unknown. In this study, we aimed to determine the signalling mechanism of extracellular vimentin that facilitates axonal growth. We first identified insulin-like growth factor 1 receptor (IGF1R) as a receptor that is highly phosphorylated by vimentin stimulation. IGF1R blockades diminished vimentin- or IGF1-induced axonal growth in cultured cortical neurons. IGF1, IGF2 and insulin were not detected in the neuron culture medium after vimentin treatment. The combined drug affinity responsive target stability method and western blotting analysis showed that vimentin and IGF1 interacted with IGF1R directly. In addition, immunoprecipitation and western blotting analyses confirmed that recombinant IGF1R bound to vimentin. The results of a molecular dynamics simulation revealed that C-terminal residues (residue number 330-407) in vimentin are the most appropriate binding sites with IGF1R. Thus, extracellular vimentin may be a novel ligand of IGF1R that promotes axonal growth in a similar manner to IGF1. Our results provide novel findings regarding the role of extracellular vimentin and IGF1R in axonal growth. PMID:26170015

  9. Up-regulation of hepatocyte growth factor receptor: An amplification and targeting mechanism for hepatocyte growth factor action in acute renal failure

    Microsoft Academic Search

    YOUHUA LIU; EVELYN M. TOLBERT; LIN LIN; MICHAEL A. THURSBY; ADAM M. SUN; TOSHIKAZU NAKAMURA; LANCE D. DWORKIN

    1999-01-01

    Up-regulation of hepatocyte growth factor receptor: An amplification and targeting mechanism for hepatocyte growth factor action in acute renal failure.BackgroundHepatocyte growth factor (HGF) and its c-met receptor comprise a signaling system that has been implicated in tissue repair and regeneration. HGF action is specifically targeted to the damaged organ following injury; however, the mechanism underlying this important targeting process remains

  10. Elevation of Transforming Growth Factor a and Its Relationship to the Epidermal Growth Factor and aFetoprotein Levels in Patients with Hepatocellular Carcinoma1

    Microsoft Academic Search

    Yun-Chi Yeh; Jung-Fa Tsai; Lea-Yea Chuang; Hsing-Wu Yeh; Juei-Hsiung Tsai; Dagne L. Fiorine; James P. Tarn

    1987-01-01

    A radioimmunoassay for transforming growth factor a (TGF-a) using synthetic rat sarcoma transforming growth factor and its rabbit polyclonal antibody has been developed. Using radioimmunoassays, the urinary TGF-a and epidermal growth factor (EGF) concentrations in 31 patients with hepatocellular carcinoma (11(< I. 15 probable HCC, four metastatic liver cancer, and 33 age, sex-matched healthy controls were determined. For the first

  11. Influence of fetal calf serum, fibroblast growth factors, and hepatocyte growth factor on three-dimensional cultures of human keratocytes in collagen gel matrix

    Microsoft Academic Search

    Vincent M. Borderie; Najat Mourra; Laurent Laroche

    1999-01-01

    · Background:We set out to evaluate the influence of fetal calf serum, acidic fibroblast growth factor (aFGF), basic fibroblast\\u000a growth factor (bFGF), and hepatocyte growth factor (HGF) on three- dimensional cultures of human keratocytes in type I collagen\\u000a gel matrix. · Methods: Polymerized gels were cultured at 37°C for 35 days. Gel contraction and integrated optical density\\u000a were assessed 3

  12. Longitudinal analysis of serum insulin-like growth factor-I and insulin-like growth factor binding protein-1 in antiphospholipid syndrome and in healthy pregnancy

    Microsoft Academic Search

    Sophia Stone; Kate Langford; Paul T. Seed; Munther A. Khamashta; Beverley J. Hunt; Lucilla Poston

    2003-01-01

    Objective: The purpose of this study was to determine the concentrations of serum insulin-like growth factor-I and insulin-like growth factor binding protein-1 in pregnancies that are complicated with primary antiphospholipid syndrome. Study Design: Longitudinal blood samples were collected from 8 weeks of gestation in 28 women with treated primary antiphospholipid syndrome and 19 control women. Serum insulin-like growth factor-I and

  13. Relationship between circulating serum soluble interleukin-6 receptor and the angiogenic cytokines basic fibroblast growth factor and vascular endothelial growth factor in multiple myeloma

    Microsoft Academic Search

    M. G. Alexandrakis; F. H. Passam; A. Boula; A. Christophoridou; G. Aloizos; P. Roussou; D. S. Kyriakou

    2003-01-01

    Angiogenesis plays an important role in multiple myeloma (MM) progression. Various mitogens such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (FGF-2) have been implicated in the angiogenic process of various malignancies. Interleukin-6 (IL-6) is a growth factor of myeloma cells and its signaling is mediated via a cell surface receptor complex (IL-6r). IL-6 and tumor necrosis

  14. Clinical significance of growth differentiation factor 11 in colorectal cancer.

    PubMed

    Yokoe, Takeshi; Ohmachi, Takahiro; Inoue, Hiroshi; Mimori, Koshi; Tanaka, Fumiaki; Kusunoki, Masato; Mori, Masaki

    2007-11-01

    Growth differentiation factor 11 (GDF11), a member of the transforming growth factor-beta superfamily and bone morphogenetic protein (BMP) subfamily, plays a role in regulation of development and differentiation. Although some members of BMP subfamily have been reported to correlate with cancer, the significance of GDF11 has not been studied in a clinical oncology setting. The current study explored the clinicopathological significance of GDF11 expression in colorectal cancer. Quantitative real-time reverse transcription-PCR in colorectal cancer specimens obtained from 130 patients showed that GDF11 mRNA expression in cancer tissue was significantly higher than in normal tissue (p=0.001). Tumors were classified as high GDF11 expression (n=65) or low GDF11 expression (n=65). Patients whose tumors had high GDF11 expression showed a high frequency of lymph node metastasis (p=0.049) and had more cancer-related deaths (p=0.040). Furthermore, the patients with high GDF11 expression had significantly poorer overall survival than those with low expression (p=0.0334). Although multivariate analysis showed that GDF11 was not an independent prognostic factor, these findings suggest that GDF11 may be a novel diagnostic and prognostic biomarker in patients with colorectal cancer. PMID:17912435

  15. TGF-?/HA complex promotes tympanic membrane keratinocyte migration and proliferation via ErbB1 receptor

    SciTech Connect

    Mei Teh, Bing, E-mail: bing.teh@earscience.org.au [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Department of Otolaryngology, Head, Neck and Skull Base Surgery, Sir Charles Gairdner Hospital, Nedlands, WA (Australia); Redmond, Sharon L. [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Shen, Yi [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Department of Otolaryngology, Head and Neck, Ningbo Lihuili Hospital (Ningbo Medical Centre), Ningbo, Zhejiang (China); Atlas, Marcus D. [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Department of Otolaryngology, Head, Neck and Skull Base Surgery, Sir Charles Gairdner Hospital, Nedlands, WA (Australia); Marano, Robert J.; Dilley, Rodney J. [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia)

    2013-04-01

    Tympanic membrane perforations are common and represent a management challenge to clinicians. Current treatments for chronic perforations involve a graft surgery and require general anaesthesia, including associated costs and morbidities. Bioactive molecules (e.g. growth factors, cytokines) play an important role in promoting TM wound healing following perforation and the use of growth factors as a topical treatment for tympanic membrane perforations has been suggested as an alternative to surgery. However, the choice of bioactive molecules best suited to promote wound healing has yet to be identified. We investigated the effects of hyaluronic acid, vitronectin, TGF-?, IL-24 and their combinations on migration, proliferation and adhesion of cultured human tympanic membrane-derived keratinocytes (hTM), in addition to their possible mechanisms of action. We found that TGF-?, TGF-?/HA and TGF-?/IL-24 promoted wound healing by significantly increasing both migration and proliferation. TGF-? and/or HA treated cells showed comparable cell–cell adhesion whilst maintaining an epithelial cell phenotype. With the use of receptor binding inhibitors for ErbB1 (AG1478) and CD44 (BRIC235), we revealed that the activation of ErbB1 is required for TGF-?/HA-mediated migration and proliferation. These results suggest factors that may be incorporated into a tissue-engineered membrane or directly as topical treatment for tympanic membrane perforations and hence reduce the need for a surgery. - Highlights: ? TGF-?, TGF-?/HA and TGF-?/IL-24 improved hTM keratinocyte migration and proliferation. ? TGF-? and/or HA maintained epithelial cell phenotype. ? TGF-?/HA-mediated migration and proliferation requires activation of ErbB1 receptor.

  16. Insulin-like growth factors, insulin-like growth factor-binding proteins, insulin-like growth factor-binding protein-3 protease, and growth hormone-binding protein in lipodystrophic Human Immunodeficiency Virus-infected patients

    Microsoft Academic Search

    Steen B. Haugaard; Ove Andersen; Birgitte R. Hansen; Hans; Ulrik B. Andersen; Sten Madsbad; Johan Iversen; Allan Flyvbjerg

    2004-01-01

    Human immunodeficiency virus (HIV)-lipodystrophy is associated with impaired growth hormone (GH) secretion. It remains to be elucidated whether insulin-like growth factors (IGFs), IGF-binding proteins (IGFBPs), IGFBP-3 protease, and GH-binding protein (GHBP) are abnormal in HIV-lipodystrophy. These parameters were measured in overnight fasting serum samples from 16 Caucasian males with HIV-lipodystrophy (LIPO) and 15 Caucasian HIV-infected males without lipodystrophy (NONLIPO) matched

  17. Association of Toxicity of Sorafenib and Sunitinib for Human Keratinocytes with Inhibition of Signal Transduction and Activator of Transcription 3 (STAT3)

    PubMed Central

    Yamamoto, Kazuhiro; Mizumoto, Atsushi; Nishimura, Kohji; Uda, Atsushi; Mukai, Akira; Yamashita, Kazuhiko; Kume, Manabu; Makimoto, Hiroo; Bito, Toshinori; Nishigori, Chikako; Nakagawa, Tsutomu; Hirano, Takeshi; Hirai, Midori

    2014-01-01

    Hand–foot skin reaction is a most common multi-kinase inhibitor-related adverse event. This study aimed to examine whether the toxicity of sorafenib and sunitinib for human keratinocytes was associated with inhibiting signal transduction and activator of transcription 3 (STAT3). We studied whether STAT3 activity affects sorafenib- and sunitinib-induced cell growth inhibition in HaCaT cells by WST-8 assay. Stattic enhanced the cell-growth inhibitory and apoptotic effects of sorafenib and sunitinib. HaCaT cells transfected with constitutively-active STAT3 (STAT3C) were resistant to the sorafenib- and sunitinib-induced cell growth inhibition. STAT3 activity decreased after short-term treatment with sorafenib and sunitinib in a dose-dependent manner and recovered after long-term treatment with sorafenib and sunitinib at low doses. Moreover, the expression of survivin and bcl-2 decreased after treatment with sorafenib and sunitinib was concomitant with variations in STAT3 activity. Sorafenib-induced STAT3 inhibition was mediated by regulation via MAPK pathways in HaCaT cells, while sunitinib-induced STAT3 inhibition was not. Thus, STAT3 activation mediating apoptosis suppressors may be a key factor in sorafenib and sunitinib-induced keratinocyte cytotoxicity. PMID:25013907

  18. Identification of the major fibroblast growth factors released spontaneously in inflammatory arthritis as platelet derived growth factor and tumour necrosis factor-alpha.

    PubMed Central

    Thornton, S C; Por, S B; Penny, R; Richter, M; Shelley, L; Breit, S N

    1991-01-01

    Rheumatoid arthritis is characterized by chronic inflammation and proliferation of a number of important elements within the joint including the synovial fibroblasts. Elevated levels of a number of cytokines such as Il-1, IL-2, IL-6, interferon-gamma (IFN-gamma), transforming growth factor-beta and tumour necrosis factor-alpha (TNF-alpha) have been detected in the synovial fluid of patients with rheumatoid arthritis and other inflammatory arthritides. It seems likely that local release of such mediators may be responsible for the proliferation and overgrowth of connective tissue elements in these disorders. In order to ascertain whether there was evidence to suggest local production or release of fibroblast growth factors in the joint in inflammatory arthritis, and to determine their identity, cells were obtained from the synovial fluid of 15 patients with chronic inflammatory arthritides. All subjects' synovial fluid cells spontaneously released growth factor activity for fibroblasts. This was present in large amounts, being detectable in culture supernatants diluted to a titre of at least 1/625. By a series of depletion experiments using solid-phase bound antibodies to cytokines, it was possible to demonstrate that this activity was due to TNF-alpha and platelet-derived growth factor (PDGF). Thus, this study showed for the first time that functionally active PDGF was released from synovial fluid cells. Both PDGF and TNF-alpha appeared to contribute in approximately equal amounts to this fibroblast growth factor activity, and were synergistic in effect. Thus this study provides evidence for the local production and release of these two cytokines and suggests that together they are the dominant factors in fibroblast proliferation within the synovial cavity. PMID:1914237

  19. Vascular Endothelial Growth Factor Receptor -2 in Breast Cancer

    PubMed Central

    Guo, Shanchun; Colbert, Laronna S.; Fuller, Miles; Zhang, Yuanyuan; Gonzalez-Perez, Ruben R.

    2010-01-01

    Investigations over the last decade have established the essential role of growth factors and their receptors during angiogenesis and carcinogenesis. The vascular endothelial growth factor receptor (VEGFR) family in mammals contains three members, VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1) and VEGFR-3 (Flt-4), which are transmembrane tyrosine kinase receptors that regulate the formation of blood and lymphatic vessels. In the early 1990s, the above VEGFR were structurally characterized by cDNA cloning. Among these three receptors, VEGFR-2 is generally recognized to have a principal role in mediating VEGF-induced responses. VEGFR-2 is considered as the earliest marker for endothelial cell development. Importantly, VEGFR-2 directly regulates tumor angiogenesis. Therefore, several inhibitors of VEGFR-2 have been developed and many of them are now in clinical trials. In addition to targeting endothelial cells, the VEGF/VEGFR-2 system works as an essential autocrine/paracrine process for cancer cell proliferation and survival. Recent studies mark the continuous and increased interest in this related, but distinct, function of VEGF/VEGFR-2 in cancer cells: the autocrine/paracrine loop. Several mechanisms regulate VEGFR-2 levels and modulate its role in tumor angiogenesis and physiologic functions, i.e.: cellular localization/trafficking, regulation of cis-elements of promoter, epigenetic regulation and signaling from Notch, cytokines/growth factors and estrogen, etc. In this review, we will focus on updated information regarding VEGFR-2 research with respect to the molecular mechanisms of VEGFR-2 regulation in human breast cancer. Investigations in the activation, function, and regulation of VEGFR-2 in breast cancer will allow the development of new pharmacological strategies aimed at directly targeting cancer cell proliferation and survival. PMID:20462514

  20. 47 CFR 54.1303 - Calculation of the rural growth factor.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Calculation of the rural growth factor. 54.1303 Section 54.1303 Telecommunication...Carriers § 54.1303 Calculation of the rural growth factor. (a) The Rural Growth Factor (RGF) is equal to the sum...

  1. Expression of Vascular Endothelial Growth Factors and Their Receptors during Osteoblast Differentiation

    Microsoft Academic Search

    MARTINE M. L. DECKERS; MARCEL KARPERIEN; CHRIS VAN DER BENT; TAKEYOSHI YAMASHITA; SOCRATES E. PAPAPOULOS; CLEMENS W. G. M. LOWIK

    2000-01-01

    Endochondral bone formation is regulated by systemically and locally acting growth factors. A role for vascular endothelial growth factor (VEGF) in this process has recently been proposed, because inactivation of VEGF inhibits endochondral bone formation via inhibition of angio- genesis. Despite the known effect of VEGF as specific endothelial growth factor, its effects on osteoblast differentiation have not been studied.

  2. Endothelial Cell-Derived Basic Fibroblast Growth Factor: Synthesis and Deposition into Subendothelial Extracellular Matrix

    Microsoft Academic Search

    Israel Vlodavsky; Judah Folkman; Robert Sullivan; Rafael Fridman; Rivka Ishai-Michaeli; Joachim Sasse; Michael Klagsbrun

    1987-01-01

    Bovine aortic and corneal endothelial cells synthesize a growth factor that remains mostly cell-associated but can also be extracted from the subendothelial extracellular matrix (ECM) deposited by these cells. The endothelial cell-derived growth factors extracted from cell lysates and from the extracellular matrix appear to be structurally related to basic fibroblast growth factor by the criteria that they (i) bind

  3. Effects of Hypergravity Rearing on Growth Hormone and Insulin-Like Growth Factor in Rat Pups

    NASA Technical Reports Server (NTRS)

    Baer, L. A.; Chowdhury, J. H.; Grindeland, R. E.; Wade, C. E.; Ronca, A. E.

    2003-01-01

    Body weights of rat pups reared during exposure to hypergravity (hg) are significantly reduced relative to 1 g controls. In the present study, we examined in hg-reared rat pups two major contributors to growth and development, namely growth hormone (GH) and insulin-like growth factor-1 (IGF-1). Beginning on Gestational day (G)11 of the rats 22 day pregnancy, rat dams and their litters were continuously exposed to either 1.5-g or 2.0-g. On Postnatal day (P)l0, plasma GH and IGF-1 were analyzed using radioimmunoassay (RIA). Both hormones were significantly elevated in hg pups relative to 1-g control pups. Together, these findings suggest that GH and IGF-1 are not primary determinants of reduced body weights observed in hg-reared pups. The significant elevations in pup GH and IGF-1 may be related to increased physical stimulation in hypergravity.

  4. Stochastic contribution to the growth factor in the LCDM model

    SciTech Connect

    Ribeiro, A. L.B.; Andrade, A. P.A.; Letelier, P. S.

    2009-01-01

    We study the effect of noise on the evolution of the growth factor of density perturbations in the context of the LCDM model. Stochasticity is introduced as a Wiener process amplified by an intensity parameter alpha. By comparing the evolution of deterministic and stochastic cases for different values of alpha we estimate the intensity level necessary to make noise relevant for cosmological tests based on large-scale structure data. Our results indicate that the presence of random forces underlying the fluid description can lead to significant deviations from the nonstochastic solution at late times for alpha>0.001.

  5. Astrocyte Mitogen Inhibitor Related to Epidermal Growth Factor Receptor

    NASA Astrophysics Data System (ADS)

    Nieto-Sampedro, Manuel

    1988-06-01

    Epidermal growth factor (EGF) is a well-characterized polypeptide hormone with diverse biological activities, including stimulation of astrocyte division. A soluble astrocyte mitogen inhibitor, immunologically related to the EGF receptor, is present in rat brain. Injury to the brain causes a time-dependent reduction in the levels of this inhibitor and the concomitant appearance of EGF receptor on the astrocyte surface. Intracerebral injection of antibody capable of binding the inhibitor caused the appearance of numerous reactive astrocytes. EGF receptor-related inhibitors may play a key role in the control of glial cell division in both normal and injured brain.

  6. The epidermal growth factor receptor (EGRF) in lung cancer.

    PubMed

    Carcereny, Enric; Morán, Teresa; Capdevila, Laia; Cros, Sara; Vilà, Laia; de Los Llanos Gil, Maria; Remón, Jordi; Rosell, Rafael

    2015-01-01

    In the last decade, important advances have been made in understanding of cancer biology, particularly non-small-cell lung cancer (NSCLC) with the discovery of oncogenic drivers of the disease. The epidermal growth factor receptor (EGFR) gene and its pathways was the first oncogenic driver discovered to be mutated and treatable in lung cancer. Treatment with EGFR tyrosine kinase inhibitors (TKIs) is the standard of care for molecularly selected EGFR-mutant patients, while its role in unselected lung cancer patients is nowadays controversial. This review will provide an overview of the EGFR pathway and options for its treatment of lung cancer. PMID:25810955

  7. Epidermal growth factor and renin in mouse submandibular glands.

    PubMed

    Tanaka, T; Gresik, E W; Barka, T

    1981-10-01

    Epon sections of the submandibular gland of SWF/J male mouse were stained immunocytochemically for epidermal growth factor (EGF) and renin. Most cells of the granular convoluted tubules (GCT) contained both EGF and renin. However, examinations of adjacent semithin or thin sections stained for EGF and renin, respectively, revealed a small population of GCT cells that contained EGF but no renin. Within a cell all secretory granules contained both EGF and renin. The renin-negative/EGF-positive cells may represent a subpopulation of tubular cells that do not express, or carry, the renin gene. PMID:7028861

  8. Transforming Growth Factor Alpha (TGF?) Transforms Astrocytes to a Growth Supportive Phenotype after Spinal Cord Injury

    PubMed Central

    White, Robin E.; Rao, Meghan; Gensel, John C.; McTigue, Dana M.; Kaspar, Brian K.; Jakeman, Lyn B.

    2011-01-01

    Astrocytes are both detrimental and beneficial for repair and recovery after spinal cord injury (SCI). These dynamic cells are primary contributors to the growth-inhibitory glial scar, yet they are also neuroprotective and can form growth-supportive bridges upon which axons traverse. We have shown that intrathecal administration of transforming growth factor alpha (TGF?) to the contused mouse spinal cord can enhance astrocyte infiltration and axonal growth within the injury site, but the mechanisms of these effects are not well understood. The present studies demonstrate that the epidermal growth factor receptor (EGFR) is upregulated primarily by astrocytes and glial progenitors early after SCI. TGF? directly activates the EGFR on these cells in vitro, inducing their proliferation, migration, and transformation to a phenotype that supports robust neurite outgrowth. Overexpression of TGF? in vivo by intraparenchymal adeno-associated virus injection adjacent to the injury site enhances cell proliferation, alters astrocyte distribution and facilitates increased axonal penetration at the rostral lesion border. To determine if endogenous EGFR activation is required after injury, SCI was also performed on Velvet (C57BL/6J-EgfrVel/J) mice, a mutant strain with defective EGFR activity. The affected mice exhibited malformed glial borders, larger lesions, and impaired recovery of function, indicating that intrinsic EGFR activation is necessary for neuroprotection and normal glial scar formation after SCI. By further stimulating precursor proliferation and modifying glial activation to promote a growth permissive environment, controlled stimulation of EGFR at the lesion border may be considered in the context of future strategies to enhance endogenous cellular repair following injury. PMID:22016551

  9. Loss of c-myc Repression Coincides with Ovarian Cancer Resistance to Transforming Growth Factor Growth Arrest Independent of Transforming Growth Factor \\/Smad Signaling1

    Microsoft Academic Search

    Rae Lynn Baldwin; Hang Tran; Beth Y. Karlan

    2003-01-01

    Many epithelial carcinomas, including ovarian, are refractory to the antiproliferative effects of transforming growth factor (TGF) . In some cancers, TGF- resistance has been linked to TGF- receptor II (TR-II) and Smad4 mutations; however, in ovarian cancer, the mechanism of resistance remains unclear. Primary ovarian epithelial cell cultures were used as a model system to determine the mechanisms of TGF-

  10. Growth inhibition of thyroid follicular cell-derived cancers by the opioid growth factor (OGF) - opioid growth factor receptor (OGFr) axis

    Microsoft Academic Search

    Patricia J McLaughlin; Ian S Zagon; Sunny S Park; Andrea Conway; Renee N Donahue; David Goldenberg

    2009-01-01

    BACKGROUND: Carcinoma of the thyroid gland is an uncommon cancer, but the most frequent malignancy of the endocrine system. Most thyroid cancers are derived from the follicular cell. Follicular carcinoma (FTC) is considered more malignant than papillary thyroid carcinoma (PTC), and anaplastic thyroid cancer (ATC) is one of the most lethal human cancers. Opioid Growth Factor (OGF; chemical term -

  11. Aging and the growth hormone/insulin like growth factor-I axis.

    PubMed

    Sherlock, Mark; Toogood, Andrew A

    2007-01-01

    Growth hormone release and IGF-I synthesis decrease with increasing age. The regulation of the GH/IGF-I system is dependent on the integrity of the hypothalamus, pituitary and liver. During aging there are several changes which contribute to the decline in GH/IGF-I including changes in signal to the somatotrophs from growth hormone releasing hormone, somatostatin and other factors such as body composition, exercise, diet and sleep. All of these factors are discussed in detail within this review. The phenotypic similarities between aging and adult growth hormone deficiency syndrome combined with this decrease in GH/IGF-I with aging have prompted the question whether aging is a GH deficient state. The advent of recombinant growth hormone has led to a number of studies treating elderly patients with GH alone or in combination with sex steroids or exercise. The results of these studies would not back up the use of GH in elderly non-hypopituitary patients as they did not show efficacy, showed high rates of adverse events and there is also some evidence associating GH/IGF-I and risk of neoplasia. If GH therapy is to be used in this cohort of patients further long term efficacy and safety studies are required. PMID:17492509

  12. Causal factors and consequences of parent involvement growth: the second-order latent growth curve model

    Microsoft Academic Search

    Varaporn Yamtim

    The purposes of this research were to 1) assess the training needs of teachers and parents in parent involvement and 3M principle roles (M1: moral supporter, M2: monitor, and M3: mentor), 2) investigate the results of the school-based training on the teachers' skills, and 3) examine the effects of causal factors and the consequences of the parent involvement growth on

  13. Transforming Growth Factor B Subverts the Immune System into Directly Promoting Tumor Growth through Interleukin17

    Microsoft Academic Search

    Jeong-Seok Nam; Masaki Terabe; Mi-Jin Kang; Helen Chae; Nga Voong; Yu-an Yang; Arian Laurence; Aleksandra Michalowska; Mizuko Mamura; Scott Lonning; Jay A. Berzofsky; Lalage M. Wakefield

    2008-01-01

    Overexpression of the immunosuppressive cytokine trans- forming growth factor B (TGF-B) is one strategy that tumors have developed to evade effective immunesurveillance. Using transplantable models of breast and colon cancer, we made the unexpected finding that CD8+ cells in tumor-bearing animals can directly promote tumorigenesis, by a mechanism that is dependent on TGF-B. We showed that CD8+ splenocytes from tumor-bearing

  14. Nerve growth factor, human skin ulcers and vascularization. Our experience.

    PubMed

    Aloe, Luigi

    2004-01-01

    Cutaneous wound is known to elicit a series of typical cellular responses that include clotting, inflammatory infiltration, reepithelialization, the formation of granulation tissue, including new blood vessel, followed by tissue remodeling and wound contraction. The regulatory molecules implicated in these events are not well known. Neurotrophins and their receptors are trophic factors that are known to play important roles in cutaneous tissues, nerve development and reconstruction after injury. Among the neurotrophins, the nerve growth factor (NGF) was one of the earliest used for clinical studies. NGF has been tested for potential therapeutic application in neuropathies of the central and peripheral nervous system and more recently in human corneal and cutaneous ulcers. Here, I present and discuss data obtained in the last few years on the healing action of NGF in human and domestic animal skin ulcers. PMID:14699983

  15. Factors Associated with Growth in Daily Smoking among Indigenous Adolescents

    PubMed Central

    Whitbeck, Les B.; Hartshorn, Kelley J. Sittner; McQuillan, Julia; Crawford, Devan M.

    2012-01-01

    North American Indigenous adolescents smoke earlier, smoke more, and are more likely to become regular smokers as adults than youth from any other ethnic group yet we know very little about their early smoking trajectories. We use multilevel growth modeling across five waves of data from Indigenous adolescents (aged 10 to 13 years at Wave 1) to investigate factors associated with becoming a daily smoker. Several factors, including number of peers who smoked at Wave 1 and meeting diagnostic criteria for major depressive episode and conduct disorder were associated with early daily smoking. Only age and increases in the number of smoking peers were associated with increased odds of becoming a daily smoker. PMID:23794792

  16. GATA3 inhibits proliferation and induces expression of both early and late differentiation markers in keratinocytes of the human epidermis.

    PubMed

    Masse, Ingrid; Barbollat-Boutrand, Laetitia; Kharbili, Manale El; Berthier-Vergnes, Odile; Aubert, Damien; Lamartine, Jérôme

    2014-03-01

    GATA3 belongs to the GATA transcription factor family and is a crucial regulator of lymphocyte differentiation. More recently, GATA3 was shown to be involved in skin cell lineage determination, in morphogenesis and maintenance of hair follicle keratinocytes as well as in epidermal barrier formation in mouse. In human, the potential role of GATA3 in the regulation of interfollicular epidermal homeostasis was still poorly explored. We thus investigated whether GATA3 could play a role in the regulation of proliferation and/or differentiation processes in human primary keratinocytes. We silenced the expression of GATA3 by small interfering RNA in either proliferating or differentiated human primary keratinocytes and analyzed the effect on cell proliferation and differentiation. We showed that GATA3 inhibition increased cell number, BrdU incorporation and expression of the proliferation markers PCNA and Ki67, demonstrating that GATA3 can inhibit keratinocyte proliferation. Moreover, GATA3 seems to be able to induce keratinocyte differentiation since its silencing leads to a decrease of both early and late differentiation markers such as Keratins 1 and 10, Involucrin and Loricrin. Our results demonstrate that GATA3 transcription factor inhibits proliferation and induces differentiation of primary keratinocytes, which suggest that it may regulate human interfollicular epidermal renewal. PMID:24346062

  17. Augmentation of LPS-induced vascular endothelial cell growth factor production in macrophages by transforming growth factor-?1.

    PubMed

    Koide, Naoki; Odkhuu, Erdenezaya; Naiki, Yoshikazu; Tsolmongyn, Bilegtsaikhan; Ito, Kiyoaki; Komatsu, Takayuki; Yoshida, Tomoaki; Yokochi, Takashi

    2014-11-01

    The effect of LPS on the production of vascular endothelial growth factor (VEGF) was examined using RAW 264.7 macrophage cells. LPS induced VEGF production in RAW 264.7 cells and mouse peritoneal cells. LPS induced VEGF production via the expression of hypoxia inducible factor-1? and LPS-induced VEGF production was dependent on the activation of p38 MAPK and NF-?B activation· Transforming growth factor (TGF)-?1 augmented LPS-induced VEGF production, although TGF-?1 alone did not induce VEGF production. The augmentation of LPS-induced VEGF production by TGF-?1 was inhibited by a p38 MAPK inhibitor and was correlated with the phosphorylation of Smad3. The enhancing effect of TGF-?1 on LPS-induced VEGF production was observed in vivo in the skin lesions of mice receiving a subcutaneous injection of LPS. Taken together, it is suggested that LPS induced the VEGF production in macrophages and that it was augmented by TGF-?1 in vitro and in vivo. PMID:24225655

  18. Growth factor treatment enhances vestibular hair cell renewal and results in improved vestibular function

    Microsoft Academic Search

    Richard D. Kopke; Ronald L. Jackson; Geming Li; Mark D. Rasmussen; Michael E. Hoffer; Dorothy A. Frenz; Michael Costello; Peter Schultheiss; Thomas R. van de Water

    2001-01-01

    The vestibules of adult guinea pigs were lesioned with gentamicin and then treated with perilymphatic infusion of either of two growth factor mixtures (i.e., GF I or GF II). GF I contained transforming growth factor (TGF), insulin-like growth factor type one (IGF-1), and retinoic acid (RA), whereas GF II contained those three factors and brain-derived neurotrophic factor. Treatment with GF

  19. KLF10, transforming growth factor-?-inducible early gene 1, acts as a tumor suppressor.

    PubMed

    Song, Ki-Duk; Kim, Duk-Jung; Lee, Jong Eun; Yun, Cheol-Heui; Lee, Woon Kyu

    2012-03-01

    Krüppel-like factor 10 (KLF10) has been suggested to be a putative tumor suppressor. In the present study, we generated KLF10 deficient mice to explore this hypothesis in vivo. KLF10 deficient mice exhibited increased predisposition to skin tumorigenesis and markedly accelerated papilloma development after DMBA/TPA treatment. On the other hand, KLF10 deficient keratinocytes showed increased proliferation and apoptosis. In colony formation assays after oncogenic H-Ras transfection, KLF10 deficient mouse embryonic fibroblasts (MEFs) yielded more colonies than wild-type MEFs. Furthermore, KLF10 dose-dependently activated p21(WAF1/CIP1) transcription, which was independent of p53 and Sp1 binding sites in p21(WAF1/CIP1) promoter. This study demonstrates that KLF10 is a tumor suppressor and that it targets p21(WAF1/CIP1) transcription. PMID:22349513

  20. Growth factor staining patterns in the pig retina following retinal laser photocoagulation

    PubMed Central

    Xiao, M.; McLeod, D.; Cranley, J.; Williams, G.; Boulton, M.

    1999-01-01

    AIM—To identify changes in growth factor expression in miniature pig retinas following retinal laser photocoagulation.?METHODS—Pigs were sacrificed at different times (15 minutes to 42 days) post-laser and the retinas were immunolabelled for basic fibroblast growth factor, insulin-like growth factor I, transforming growth factor ?, epidermal growth factor, transforming growth factor ?, platelet derived growth factor, vascular endothelial growth factor, and epidermal growth factor receptor. Total mRNA levels were also determined.?RESULTS—With the exception of vascular endothelial growth factor, immunoreactivity for all other growth factors studied and epidermal growth factor receptor was observed throughout normal non-lasered control retina, generally being high in the retinal pigment epithelium and low in the neural retina. Changes in growth factor expression following laser photocoagulation were observed only in burn areas and changes were mainly confined to the retinal pigment epithelium and outer nuclear layer. The immunoreactivity within retinal pigment epithelial cells in burn areas was either absent or decreased following laser treatment but returned to normal by 21 days. The immunoreactivity was increased within the outer nuclear layer of burn areas during the healing process but returned to normal by 42 days. Vascular endothelial growth factor immunoreactivity was weak/absent in the normal retina and remained unchanged following laser photocoagulation. Change of total mRNA levels in burn areas during time post-laser was confined to retinal pigment epithelial cells, being low immediately following photocoagulation and returning to normal by 42 days.?CONCLUSIONS—These results demonstrate a temporal alteration in growth factor expression and transcriptional activity in the retina following laser photocoagulation.?? PMID:10340985

  1. Endocrine fibroblast growth factor FGF19 promotes prostate cancer progression

    PubMed Central

    Feng, Shu; Dakhova, Olga; Creighton, Chad J.; Ittmann, Michael

    2013-01-01

    Prostate cancer (PCa) is the most common visceral malignancy and the second leading cause of cancer deaths in US men. There is broad evidence that FGF receptors are important in PCa initiation and progression, but the contribution of particular FGFs in this disease is not fully understood. The FGF family members FGF19, FGF21 and FGF23 comprise a distinct subfamily that circulate in serum and act in an endocrine manner. These endocrine FGFs require ?-Klotho (KL) and/or ?-Klotho (KLB), two related single-pass transmembrane proteins restricted in their tissue distribution, to act as co-receptors along with classic FGFRs to mediate potent biological activity. Here we show that FGF19 is expressed in primary and metastatic PCa tissues where it functions as an autocrine growth factor. Exogenous FGF19 promoted the growth, invasion, adhesion and colony formation of PCa cells at low ligand concentrations. FGF19 silencing in PCa cells expressing autocrine FGF19 decreased invasion and proliferation in vitro and tumor growth in vivo. Consistent with these observations, KL and/or KLB were expressed in PCa cells in vitro and in vivo, raising the possibility that additional endocrine FGFs may also exert biological effects in PCa. Our findings support the concept that therapies targeting FGFR signaling these therapies may have efficacy in PCa and they highlight FGF19 as a relevant endocrine FGF in this setting. PMID:23440425

  2. Electrospinning growth factor releasing microspheres into fibrous scaffolds.

    PubMed

    Whitehead, Tonya J; Sundararaghavan, Harini G

    2014-01-01

    This procedure describes a method to fabricate a multifaceted substrate to direct nerve cell growth. This system incorporates mechanical, topographical, adhesive and chemical signals. Mechanical properties are controlled by the type of material used to fabricate the electrospun fibers. In this protocol we use 30% methacrylated Hyaluronic Acid (HA), which has a tensile modulus of ~500 Pa, to produce a soft fibrous scaffold. Electrospinning on to a rotating mandrel produces aligned fibers to create a topographical cue. Adhesion is achieved by coating the scaffold with fibronectin. The primary challenge addressed herein is providing a chemical signal throughout the depth of the scaffold for extended periods. This procedure describes fabricating poly(lactic-co-glycolic acid) (PLGA) microspheres that contain Nerve Growth Factor (NGF) and directly impregnating the scaffold with these microspheres during the electrospinning process. Due to the harsh production environment, including high sheer forces and electrical charges, protein viability is measured after production. The system provides protein release for over 60 days and has been shown to promote primary nerve cell growth. PMID:25178038

  3. Effects of transforming growth factor beta s and basic fibroblast growth factor on articular chondrocytes obtained from immobilised rabbit knees.

    PubMed Central

    Okazaki, R; Sakai, A; Nakamura, T; Kunugita, N; Norimura, T; Suzuki, K

    1996-01-01

    OBJECTIVE: To clarify the effects of transforming growth factor beta 1 (TGF beta 1), TGF beta 2, and basic fibroblast growth factor (bFGF) on cell proliferation and proteoglycan (PG) synthesis in articular chondrocytes obtained from immobilised rabbit knees. METHODS: The right knees of rabbits were immobilised in full extension for up to 42 days using fiberglass casts. Specimens for histology were stained with safranin O. Chondrocytes were isolated from the weight bearing regions of the femur and tibia of the immobilised knees and cultured with combinations of growth factors. Cell proliferation and PG synthesis were determined by 3H-thymidine and 35S-sulphate incorporations. RESULTS: Histological study revealed loss of metachromasia in the articular cartilage at seven days, fissuring and cell clusters at 28 days, and loss of cartilage layers 42 days after immobilisation. Radioisotope assay of the chondrocytes revealed no remarkable change in DNA synthesis in the presence of either TGF beta 1 or TGF beta 2 alone. bFGF markedly stimulated cell proliferation in specimens obtained 0 to seven days after immobilisation. The combination of either TGF beta 1 or TGF beta 2 with bFGF had a synergistic effect, inducing significant increases in DNA synthesis four, seven, and 14 days after immobilisation. PG synthesis by chondrocytes from immobilised joints was not significantly altered by these agents. CONCLUSION: TGF beta 1 or TGF beta 2 in combination with bFGF exert synergistic effects on cell proliferation in articular chondrocytes obtained from the rabbit knee during the early days after immobilisation by a cast. These results suggest a critical role of cytokine combinations in the development of articular cartilage degeneration after immobilisation. Images PMID:8712881

  4. Differential inhibition of nerve growth factor and epidermal growth factor effects on the PC12 pheochromocytoma line

    PubMed Central

    1984-01-01

    Tests have been made of the action of the methyltransferase inhibitors 5'-S-methyl adenosine, 5'-S-(2-methyl-propyl)-adenosine, and 3-deaza- adenosine +/- L-homocysteine thiolactone, on nerve growth factor (NGF)- dependent events in the rat pheochromocytoma line PC12. Each of these agents inhibited NGF-dependent neurite outgrowth at concentrations of the order of millimolar. Slow initiation of neurite outgrowth over several days and more rapid regeneration of neurites (congruent to 1 d) were blocked, as was the priming mechanism necessary for genesis of neurites. The inhibitions were reversible in that PC12 cells maintained for several days in the presence of inhibitors grew neurites normally after washout of these agents. Other NGF-dependent responses of the PC12 line (i.e., induction of ornithine decarboxylase activity [over 4 h], enhancement of tyrosine hydroxylase phosphorylation [over 1 h], and rapid changes in cell surface morphology [30 s onward]) were inhibited by each of the agents. In contrast, corresponding epidermal growth factor-dependent responses in ornithine decarboxylase activity, phosphorylation, and cell surface morphology were not blocked, but instead either unaffected or enhanced, by the methylation inhibitors. These inhibitors did not act by blockade of binding of NGF to high- or low-affinity cell surface receptors, though they partially inhibited internalization of [125I]NGF. The inhibition of rapidly-induced NGF- dependent events and the differential inhibition of responses to NGF and epidermal growth factor imply that the methyltransferase inhibitors specifically block one of the first steps in the mechanistic pathway for NGF. PMID:6319427

  5. Understanding Cytokine and Growth Factor Receptor Activation Mechanisms

    PubMed Central

    Atanasova, Mariya; Whitty, Adrian

    2012-01-01

    Our understanding of the detailed mechanism of action of cytokine and growth factor receptors – and particularly our quantitative understanding of the link between structure, mechanism and function – lags significantly behind our knowledge of comparable functional protein classes such as enzymes, G protein-coupled receptors, and ion channels. In particular, it remains controversial whether such receptors are activated by a mechanism of ligand-induced oligomerization, versus a mechanism in which the ligand binds to a pre-associated receptor dimer or oligomer that becomes activated through subsequent conformational rearrangement. A major limitation to progress has been the relative paucity of methods for performing quantitative mechanistic experiments on unmodified receptors expressed at endogenous levels on live cells. In this article we review the current state of knowledge on the activation mechanisms of cytokine and growth factor receptors, critically evaluate the evidence for and against the different proposed mechanisms, and highlight other key questions that remain unanswered. New approaches and techniques have led to rapid recent progress in this area, and the field is poised for major advances in the coming years, which promises to revolutionize our understanding of this large and biologically and medically important class of receptors. PMID:23046381

  6. Insulin-like growth factors in patients with liver cysts.

    PubMed

    Nedi?, Olgica; Nikoli?, J Anna; Baricevi?, Ivona; Jovanovi?, Biljana; Ili?, Natasa

    2004-01-01

    Insulin-like growth factors (IGFs) play an important role in cell growth and differentiation, and the liver is the main source of IGFs and IGF-binding proteins (IGFBPs) that appear in the circulation. The effect of liver cysts on the circulating IGF system was studied in this work. Serum concentrations of IGF-I and -II were measured by radioimmunoassay, IGFBP patterns were characterised by ligand-affinity and immunoblotting, and a lectin-binding assay was used to investigate the glyco component of IGFBP-3 complexes. IGF-I and -II concentrations in patients with cysts were significantly lower compared to those in healthy individuals (P<0.0001 and P<0.01, respectively), and the decrease was related to age but not sex. The overall mean concentrations of IGF-I and -II were not significantly different whether the cysts were caused by Echinococcus granulosus, cross-reactive pathologies, or some other factor. IGFBP profiles correlated with the amount of IGF present: patients with lower IGF-I concentrations expressed decreased IGFBP-3 and elevated IGFBP-2 levels. Increased IGFBP-3 proteolytic activity in the patients' blood was not detected by immunoblotting. In the lectin-binding assay, IGFBP-3 complexes in the circulation of patients demonstrated reactivity similar to that in healthy persons, suggesting that the overall structure of the saccharide moieties of the IGFBP-3 complexes was not significantly altered due to liver cyst formation. PMID:15543566

  7. Intranasal epidermal growth factor treatment rescues neonatal brain injury

    PubMed Central

    Scafidi, Joseph; Hammond, Timothy R.; Scafidi, Susanna; Ritter, Jonathan; Jablonska, Beata; Roncal, Maria; Szigeti-Buck, Klara; Coman, Daniel; Huang, Yuegao; McCarter, Robert J.; Hyder, Fahmeed; Horvath, Tamas L.; Gallo, Vittorio

    2014-01-01

    There are no clinically relevant treatments available that improve function in the growing population of very preterm infants (<32 weeks gestation) with neonatal brain injury. Diffuse white matter injury (DWMI) is a common finding in these children and results in chronic neurodevelopmental impairments1,2. As shown recently, failure in oligodendrocyte progenitor cell maturation contributes to DWMI3. In a previous study, we demonstrated that epidermal growth factor receptor (EGFR) plays an important role in oligodendrocyte development4. Here, we examine whether enhanced epidermal growth factor receptor (EGFR) signaling stimulates the endogenous response of EGFR-expressing progenitor cells during a critical period after brain injury, and promotes cellular and behavioral recovery in the developing brain. Using an established model of very preterm brain injury, we demonstrate that selective overexpression of human (h)EGFR in oligodendrocyte lineage cells or the administration of intranasal heparin binding EGF immediately after injury decreases oligodendroglia death, enhances generation of new oligodendrocytes from progenitor cells (OPCs) and promotes functional recovery. Furthermore, these interventions diminish ultrastructural abnormalities and alleviate behavioral deficits on white matter-specific paradigms. Inhibition of EGFR signaling with a molecularly targeted agent used for cancer therapy demonstrates that EGFR activation is an important contributor to oligodendrocyte regeneration and functional recovery after DWMI. Thus, our study provides direct evidence that targeting EGFR in OPCs at a specific time after injury is clinically feasible and applicable for the treatment of premature children with white matter injury. PMID:24390343

  8. Contribution of host-derived growth factors to in vivo growth of a transplantable murine mammary carcinoma.

    PubMed Central

    Davies, D. E.; Farmer, S.; White, J.; Senior, P. V.; Warnes, S. L.; Alexander, P.

    1994-01-01

    The contribution of host-derived growth factors to tumour growth in vivo was studied using the transplantable murine mammary carcinoma, MT1, grown in syngeneic mice. Promotion of growth of the mammary carcinoma by a factor(s) from the host was evident in experiments in which the carcinoma cells were inoculated intraperitoneally. In this environment, tumours develop as multiple solid nodules, each probably arising from an individual cell or a small cluster of cells. Tumour growth was found to occur in the peritoneal cavity following inoculation of 10(3) cells, but an inoculum of as few as ten cells grew if a leucocyte-rich exudate had first been induced. To determine which host-derived growth factors might contribute to growth of MT1, extracts of the tumour were first examined for growth factor activity. Fractionation of tumour extracts by either ion-exchange chromatography or gel filtration revealed several peaks of mitogenic activity, but none of this could be attributed to epidermal growth factor (EGF). Accordingly, an anti-EGF antibody was tested as a putative inhibitor of tumour growth as any effect of this antibody could be ascribed to removal of EGF derived from the host. The antibody was found to have potent anti-tumour activity when tested against MT1 tumours that had been inoculated into the peritoneal cavity. In contrast, the antibody had little effect on growth of the discrete tumour mass which formed when MT1 was transplanted subcutaneously. The results suggest that host-derived EGF contributes to establishment of microcolonies of MT1 carcinoma within the peritoneal cavity. This may be directly, by providing growth factors to supplement those produced by the tumour until it reaches a certain critical mass to sustain autocrine growth, or indirectly, by affecting the production of other growth-stimulatory factors or cytokines. PMID:8054274

  9. The effects of Malassezia yeasts on cytokine production by human keratinocytes.

    PubMed

    Watanabe, S; Kano, R; Sato, H; Nakamura, Y; Hasegawa, A

    2001-05-01

    Yeasts of Malassezia, members of the microbiologic flora of the skin, cause pityriasis versicolor and have also been implicated in the pathogenesis of other superficial dermatoses; the most important ones are seborrheic dermatitis, folliculitis, and atopic dermatitis. The mechanisms by which the yeasts cause these dermatose? however, are not yet clear, and there have been no studies on the interaction between fungi and keratinocytes, especially the effects of fungi on the production of cytokines by human keratinocytes. Recently, the genus Malassezia has been expanded to seven species based on molecular data. In this study, we estimated the effects of Malassezia yeasts on cytokine (interleukins 1beta, 6, and 8, monocyte chemotactic protein-1, and tumor necrosis factor-alpha) production by human keratinocytes in order to examine whether the pathogenicity of the respective Malassezia yeasts is different from each other and to elucidate the mechanism by which Malassezia yeasts cause the dermatoses with different clinical and pathologic manifestations. Variable levels of interleukin 6 and 8, and tumor necrosis factor-alpha in the supernatants in response to Malassezia yeasts (except M. furfur) increased from 1 to 24 h co-culture, but the monocyte chemotactic protein-1 was undetectable. Furthermore, cytokine levels in the supernatants were undetectable 1-24 h after the keratinocytes were harvested with only supernatants of Malassezia. These results indicate that Malassezia stimulates cytokine production by keratinocytes, the cytokine production needs the presence of Malassezia, and there are differences in ability to induce cytokine production by human keratinocytes among Malassezia yeasts. These differences may reflect the different inflammatory responses in Malassezia-associated dermatoses, resulting in different clinical and pathologic manifestations. PMID:11348468

  10. Divergent Effects of Epidermal Growth Factor and Transforming Growth Factors on a Human Endometrial Carcinoma Cell Line1

    Microsoft Academic Search

    Murray Kore; Carol A. Haussler; Nathan S. Trookman

    1987-01-01

    Epidermal growth factor (EGF), at concentrations ranging from 0.83 to 4.98 UM,markedly inhibited the proliferation of RL95-2 cells that were seeded at low plating densities (4.7 x 1(1'cells\\/cm2). Under the same incubation conditions, 16.6 pM EGF enhanced cell proliferation. At high plating densities (2.5 x Id4 cells\\/cm2)0.83 UMEGF also stimulated cell proliferation. Both the inhibitory and stimulatory effects of EGF

  11. Neurotrophin4 Production by Human Epidermal Keratinocytes: Increased Expression in Atopic Dermatitis

    Microsoft Academic Search

    Markus Grewe; Kathrin Vogelsang; Thomas Ruzicka; Helger Stege; Jean Krutmann

    2000-01-01

    Chronic inflammatory conditions of human skin, such as prurigo lesions of atopic dermatitis, are characterized clinically by intense pruritus and histologically by increased innervation. Regulation of skin innervation is thought to depend on neurotrophic factors. In this study, human skin cells were identified as a source of neurotrophins. Cultured keratinocytes expressed neurotrophin-4, whereas dermal fibroblasts expressed neurotrophin-3. In vitro stimulation

  12. Transcriptional Activation of Endogenous Retroviral Sequences in Human Epidermal Keratinocytes by UVB Irradiation

    Microsoft Academic Search

    Christine Hohenadl; Herbert Germaier; Monika Walchner; Manuela Hagenhofer; Martin Herrmann; Michael Stürzl; Peter Kind; Rüdiger Hehlmann; Volker Erfle; Christine Leib-Mösch

    1999-01-01

    Ultraviolet radiation is a pathogenic factor in various diseases, e.g., autoimmune disorders such as lupus erythematosus. On the other hand, endogenous retroviruses are discussed as etiologic agents in lupus erythematosus. Therefore, we investigated the influence of ultraviolet irradiation on expression of human endogenous retroviral sequences and human endogenous retroviral sequence promoter-driven transcription of cellular genes using human epidermal keratinocytes as

  13. Abnormal NF-kappaB signaling pathway with enhanced susceptibility to apoptosis in immortalized keratinocytes.

    PubMed

    Chaturvedi, V; Qin, J Z; Denning, M F; Choubey, D; Diaz, M O; Nickoloff, B J

    2001-05-01

    The transcriptional activation and proper regulation of NF-kappaB is known to be important to the apoptotic resistant phenotype of epidermal-derived keratinocytes. By comparing and contrasting the responses of normal foreskin-derived keratinocytes versus an immortalized skin-derived keratinocyte cell line (i.e. HaCaT cells), several molecular defects involving NF-kappaB signaling pathway were delineated in the immortalized keratinocytes. While exposure to IFN-gamma plus TPA produces growth arrest in both normal and immortalized keratinocytes, with rapid phosphorylation of MEKKI and recruitment of distinctive protein kinase C isoforms into the signalosome complex, subsequent molecular events necessary for NF-kappaB activation were abnormal in HaCaT cells. This disrupted NF-kappaB activation in HaCaT cells was accompanied by enhanced susceptibility to UV-light induced apoptosis, which was associated with elevated levels of E2F-1 and decreased TRAF1/TRAF2 levels. Additional defects in HaCaT cells included markedly diminished levels of IKKbeta (and lack of induction of kinase activity) in response to inflammatory stimuli, a failure of p21(WAF1/CIP1) to associate with CDK2, and a decreased association between p65 and p300. These studies suggest caution in using HaCaT cells as a substitute for normal keratinocytes to study apoptosis in the skin. Thus, it appears that while the immortalized cells can escape cell cycle checkpoints by elevated levels of E2F-1, an adverse biological consequence of such dysregulated cell cycle control is the inability to activate the anti-apoptotic NF-kappaB signaling pathway. Therefore, exploiting this apoptosis vulnerability in pre-malignant, or immortalized cells, prior to acquiring a death-defying phenotype characteristic of more advanced malignant cell types, provides the basis for an early interventional therapeutic strategy for cutaneous oncologists. PMID:11323223

  14. Vaccinia Virus Induces Rapid Necrosis in Keratinocytes by a STAT3-Dependent Mechanism

    PubMed Central

    He, Yong; Fisher, Robert; Chowdhury, Soma; Sultana, Ishrat; Pereira, Claudia P.; Bray, Mike; Reed, Jennifer L.

    2014-01-01

    Rationale Humans with a dominant negative mutation in STAT3 are susceptible to severe skin infections, suggesting an essential role for STAT3 signaling in defense against cutaneous pathogens. Methods To focus on innate antiviral defenses in keratinocytes, we used a standard model of cutaneous infection of severe combined immunodeficient mice with the current smallpox vaccine, ACAM-2000. In parallel, early events post-infection with the smallpox vaccine ACAM-2000 were investigated in cultured keratinocytes of human and mouse origin. Results Mice treated topically with a STAT3 inhibitor (Stattic) developed larger vaccinia lesions with higher virus titers and died more rapidly than untreated controls. Cultured human and murine keratinocytes infected with ACAM-2000 underwent rapid necrosis, but when treated with Stattic or with inhibitors of RIP1 kinase or caspase-1, they survived longer, produced higher titers of virus, and showed reduced activation of type I interferon responses and inflammatory cytokines release. Treatment with inhibitors of RIP1 kinase and STAT3, but not caspase-1, also reduced the inflammatory response of keratinocytes to TLR ligands. Vaccinia growth properties in Vero cells, which are known to be defective in some antiviral responses, were unaffected by inhibition of RIP1K, caspase-1, or STAT3. Conclusions Our findings indicate that keratinocytes suppress the replication and spread of vaccinia virus by undergoing rapid programmed cell death, in a process requiring STAT3. These data offer a new framework for understanding susceptibility to skin infection in patients with STAT3 mutations. Interventions which promote prompt necroptosis/pyroptosis of infected keratinocytes may reduce risks associated with vaccination with live vaccinia virus. PMID:25419841

  15. Expression of basic fibroblast growth factor is associated with poor outcome in non-Hodgkin's lymphoma

    PubMed Central

    Pazgal, I; Zimra, Y; Tzabar, C; Okon, E; Rabizadeh, E; Shaklai, M; Bairey, O

    2002-01-01

    It is now clear that angiogenesis and angiogenesis factors are important in the pathogenesis of haematological malignancies. High pretreatment levels of serum basic fibroblast growth factor have been shown to be associated with poor prognosis in patients with non-Hodgkin's lymphoma. The aim of this study was to evaluate whether non-Hodgkin's lymphoma cells express basic fibroblast growth factor and/or its receptor (fibroblast growth factor receptor-1) and whether basic fibroblast growth factor expression correlates with basic fibroblast growth factor serum levels, intratumoral microvessel density, and patient outcome. We measured basic fibroblast growth factor by enzyme-linked immunosorbent assay in sera taken from 58 patients with non-Hodgkin's lymphoma before treatment and in 19 of them also after treatment. Pathological specimens at diagnosis were evaluated by immunohistochemistry staining using polyoclonal antibody against factor-VIII-related antigen, basic fibroblast growth factor and fibroblast growth factor receptor-1 to determine the expression of the microvessel count and basic fibroblast growth factor and fibroblast growth factor receptor-1. The lymphoma specimens demonstrated positive staining for basic fibroblast growth factor (in 23%) and fibroblast growth factor receptor-1 (in 58.5%). The patients who expressed basic fibroblast growth factor had a significantly worse progression-free and overall survival than those who did not (P=0.003 and P=0.03 respectively), while patients expressing fibroblast growth factor receptor-1 were less likely to achieve complete remission than those lacking the receptor (33% vs 65% , P=0.047). There was no correlation of basic fibroblast growth factor staining with either serum basic fibroblast growth factor levels or microvessel count. Basic fibroblast growth factor serum levels did not change significantly after treatment These results suggest that non-Hodgkin's lymphoma specimens express basic fibroblast growth factor and its receptor (fibroblast growth factor receptor-1) and this expression is associated with poor patient outcome. British Journal of Cancer (2002) 86, 1770–1775. doi:10.1038/sj.bjc.6600330 www.bjcancer.com © 2002 Cancer Research UK PMID:12087465

  16. p63-microRNA feedback in keratinocyte senescence.

    PubMed

    Rivetti di Val Cervo, Pia; Lena, Anna Maria; Nicoloso, Milena; Rossi, Simona; Mancini, Mara; Zhou, Huiqing; Saintigny, Gaelle; Dellambra, Elena; Odorisio, Teresa; Mahé, Christian; Calin, George Adrian; Candi, Eleonora; Melino, Gerry

    2012-01-24

    We investigated the expression of microRNAs (miRNAs) associated with replicative senescence in human primary keratinocytes. A cohort of miRNAs up-regulated in senescence was identified by genome-wide miRNA profiling, and their change in expression was validated in proliferative versus senescent cells. Among these, miRNA (miR)-138, -181a, -181b, and -130b expression increased with serial passages. miR-138, -181a, and -181b, but not miR-130b, overexpression in proliferating cells was sufficient per se to induce senescence, as evaluated by inhibition of BrdU incorporation and quantification of senescence-activated ?-galactosidase staining. We identified Sirt1 as a direct target of miR-138, -181a, and -181b, whereas ?Np63 expression was inhibited by miR-130b. We also found that ?Np63? inhibits miR-138, -181a, -181b, and -130b expression by binding directly to p63-responsive elements located in close proximity to the genomic loci of these miRNAs in primary keratinocytes. These findings suggest that changes in miRNA expression, by modulating the levels of regulatory proteins such as p63 and Sirt1, strongly contribute to induction of senescence in primary human keratinocytes, thus linking these two proteins. Our data also indicate that suppression of miR-138, -181a, -181b, and -130b expression is part of a growth-promoting strategy of ?Np63? in epidermal proliferating cells. PMID:22228303

  17. Synergistic effects of bombesin and epidermal growth factor on cancers.

    PubMed Central

    Liebow, C; Crean, D H; Lee, M T; Kamer, A R; Mang, T S; Schally, A V

    1994-01-01

    Bombesin and gastrin-releasing peptide act as autocrine mitogens in various cancers. Bombesin antagonist RC-3095 inhibited growth in some cancers and slowed the progression of premalignant lesions, possibly by down-regulating epidermal growth factor (EGF) receptors. Since the EGF receptor mitogen response involves tyrosine kinase stimulation, we tested the hypotheses that bombesin stimulates, and RC-3095 inhibits, phosphorylation; EGF and bombesin promote the phosphorylation of the same substrates; and EGF and bombesin act synergistically on phosphorylation. Therefore, in vitro assays for phosphorylation were performed in the presence or absence of EGF, bombesin, RC-3095, and combinations in samples derived from tumor, tissue surrounding tumor, cell lines, and normal and transforming tissue derived from the 9,10-dimethyl-1,2-benzanthracene-induced squamous cell lesions of the hamster cheek pouch. Bombesin increased, and RC-3095 decreased, phosphorylation in these samples. In the human hepatoma sample and surrounding tissue, these ligands altered the phosphorylation of the same substrates affected by EGF. EGF and bombesin stimulated phosphorylation synergistically in the hamster samples and the hepatoma. Bombesin-induced phosphorylation was greater in tissue surrounding the hepatoma, whereas RC-3095 was more effective in inhibiting phosphorylation in the hepatoma itself. This cancer, therefore, could be endogenously stimulated by gastrin-releasing peptide. These observations support the hypothesis that bombesin stimulates growth of tissues and tumors by amplifying the phosphorylation response to EGF. The growth inhibitory response to RC-3095, or other bombesin analogues, of individual tumors may be prognosed by in vitro phosphorylation assays using the samples from the patient's tumor. Images PMID:8170991

  18. MET kinase inhibitor SGX523 synergizes with epidermal growth factor receptor inhibitor erlotinib in a hepatocyte growth factor-dependent fashion to suppress carcinoma growth.

    PubMed

    Zhang, Yu-Wen; Staal, Ben; Essenburg, Curt; Su, Yanli; Kang, Liang; West, Rich; Kaufman, Dafna; Dekoning, Tom; Eagleson, Bryn; Buchanan, Sean G; Vande Woude, George F

    2010-09-01

    The hepatocyte growth factor (HGF)-MET pathway supports several hallmark cancer traits, and it is frequently activated in a broad spectrum of human cancers (http://www.vai.org/met/). With the development of many cancer drugs targeting this pathway, there is a need for relevant in vivo model systems for preclinical evaluation of drug efficacy. Here, we show that production of the human HGF ligand in transgenic severe combined immunodeficient mice (hHGF(tg)-SCID mice) enhances the growth of many MET-expressing human carcinoma xenografts, including those derived from lung, breast, kidney, colon, stomach, and pancreas. In this model, the MET-specific small-molecule kinase inhibitor SGX523 partially inhibits the HGF-dependent growth of lung, breast, and pancreatic tumors. However, much greater growth suppression is achieved by combinatorial inhibition with the epidermal growth factor receptor (EGFR) kinase inhibitor erlotinib. Together, these results validate the hHGF(tg)-SCID mouse model for in vivo determination of MET sensitivity to drug inhibition. Our findings also indicate that simultaneously targeting the MET and EGFR pathways can provide synergistic inhibitory effects for the treatment of cancers in which both pathways are activated. PMID:20643778

  19. The growth factor independence-1 transcription factor: New functions and new insights?

    PubMed Central

    Kazanjian, Avedis; Gross, Eleanore A.; Grimes, H. Leighton

    2010-01-01

    The growth factor independence-1 (Gfi1) transcription factor is required for proper development of neuroendocrine cells, sensory neurons, and blood. Patients with mutations in Gfi1 exhibit severe congenital neutropenia (SCN) or non-immune chronic idiopathic neutropenia of adults. Gfi1 was initially described as an oncoprotein that mediates tumor progression in a mouse model of leukemia; however, recent data suggest that Gfi1 may act as either an oncogene or an anti-proliferative tumor suppressor gene depending on the cell type. Here we review the latest literature on Gfi1, and emphasize its role in the hematopoietic, sensory and neuroendocrine systems. PMID:16716599

  20. A Histologically Distinctive Interstitial Pneumonia Induced by Overexpression of the Interleukin 6, Transforming Growth Factor ?1, or Platelet-Derived Growth Factor B Gene

    NASA Astrophysics Data System (ADS)

    Yoshida, Mitsuhiro; Sakuma, Junko; Hayashi, Seiji; Abe, Kin'ya; Saito, Izumu; Harada, Shizuko; Sakatani, Mitsunoir; Yamamoto, Satoru; Matsumoto, Norinao; Kaneda, Yasufumi; Kishmoto, Tadamitsu

    1995-10-01

    Interstitial pneumonia is characterized by alveolitis with resulting fibrosis of the interstitium. To determine the relevance of humoral factors in the pathogenesis of interstitial pneumonia, we introduced expression vectors into Wistar rats via the trachea to locally overexpress humoral factors in the lungs. Human interleukin (IL) 6 and IL-6 receptor genes induced lymphocytic alveolitis without marked fibroblast proliferation. In contrast, overexpression of human transforming growth factor ?1 or human platelet-derived growth factor B gene induced only mild or apparent cellular infiltration in the alveoli, respectively. However, both factors induced significant proliferation of fibroblasts and deposition of collagen fibrils. These histopathologic changes induced by the transforming growth factor ?1 and platelet-derived growth factor B gene are partly akin to those changes seen in lung tissues from patients with pulmonary fibrosis and markedly contrast with the changes induced by overexpression of the IL-6 and IL-6 receptor genes that mimics lymphocytic interstitial pneumonia.

  1. Redirection of B cell responsiveness by transforming growth factor ? receptor

    PubMed Central

    Roes, Jürgen; Choi, B. Ken; Cazac, Balthazar B.

    2003-01-01

    The multifunctional transforming growth factor ? receptor (T?R) ligand pair plays a central role in the regulation of lymphocyte homeostasis and prevention of autoimmunity. Although the mechanisms underlying the induction of transcriptional modulators by T?R have been studied in considerable detail, relatively little is known about the regulatory pathways targeted. To shed light on the mechanisms involved in negative regulation of B cell responses we identified T?R-dependent transcriptome changes by comparative gene expression profiling of normal and T?R-deficient primary B cells. The data reveal T?R-mediated induction of inhibitors of antigen receptor signaling (Ship-1, CD72) as well as inhibitors of the Jak/Stat pathway and signaling by means of Toll-like receptors (SOCS1,3). These inhibitory effects are complemented by induction of antiproliferative transcription factors. In contrast to this inhibition, G protein-coupled receptors such as CXCR4 and agonists mediating Ca2+ flux (inositol trisphosphate receptor subtype 2) are induced by T?R, indicating enhancement of the Ca2+ storage/ release system and chemotactic responses. Suppression of proapoptotic genes suggests support of cell survival. Confirming the shift in B cell responsiveness, antigen-receptor-mediated activation of Syk and phospholipase C-?2, as well as Stat6 phosphorylation, is inhibited, whereas chemotaxis, Ca2+ release, and cell survival are enhanced in transforming growth factor-?-sensitive B cells. The data provide a molecular basis for T?R-mediated inhibition of B cell responsiveness and indicate that T?R maintains homeostasis not only through inhibition of the cell cycle but also by delivering a coherent instructive signal that redirects responsiveness to microenvironmental cues. PMID:12773615

  2. Nerve Growth Factor Is an Autocrine Survival Factor for Memory B Lymphocytes

    Microsoft Academic Search

    Maria Torcia; Luisa Bracci-Laudiero; Maria Lucibello; Lucia Nencioni; Danilo Labardi; Anna Rubartelli; Federico Cozzolino; Luigi Aloe; Enrico Garaci

    1996-01-01

    Production of nerve growth factor (NGF) was assessed in cultures of human T and B lymphocytes and macrophages. NGF was constitutively produced by B cells only, which also expressed surface p140trk-A and p75NGFR molecules and hence efficiently bound and internalized the cytokine. Neutralization of endogenous NGF caused disappearance of Bcl-2 protein and apoptotic death of resting lymphocytes bearing surface IgG

  3. Characterization and growth factor stimulation of l -arginine transport in a human colon cancer cell line

    Microsoft Academic Search

    Juan Carlos Cendan; Wiley W. Souba; Edward M. Copeland III; D. Scott Lind

    1995-01-01

    Background: Epidermal growth factor (EGF) and transforming growth factor ? (TGF?) are potent mitogens that contribute to abnormal growth\\u000a regulation in colon cancer. Growth factors have been shown to regulate transmembrane nutrient uptake as an adaptive response\\u000a to support cellular proliferation.\\u000a \\u000a \\u000a Methods: The transport of L-arginine by the SW480 primary human colon adenocarcinoma cell line was characterized by assaying the

  4. Mechanism of T-cell lymphomagenesis: transformation of growth-factor-dependent T-lymphoblastoma cells to growth-factor-independent T-lymphoma cells.

    PubMed

    Haas, M; Altman, A; Rothenberg, E; Bogart, M H; Jones, O W

    1984-03-01

    In a previous paper we described the induction by x-irradiation or radiation-induced leukemia virus-inoculation of two classes of lymphoid T-cell neoplasms: The first class, designated T-cell lymphoblastoma (TCLB), consists of growth-factor-dependent eudiploid cells that home to the spleen and give rise to splenic tumors on injection into syngeneic mice; the second class, designated T-cell lymphoma (TCL), consists of growth-factor-independent aneuploid or pseudodiploid cells that give rise to local tumors at the site of subcutaneous injection. This paper describes the generation of a family of growth-factor-independent aneuploid or pseudodiploid TCL cells after the injection into the thymus of growth-factor-dependent diploid TCLB cells. In contrast to the donor TCLB cells, the resulting TCL cells could be cloned in semisolid medium, produced local tumors at the site of subcutaneous injection, and proliferated in a growth-factor-independent fashion in vitro. The induced growth-factor-independent TCL cells were chromosomally and phenotypically unstable and continued to evolve both in vivo and in vitro. After propagation in the thymus, the cells often showed stable translocations in addition to the evolving aneuploidy. We propose that the chromosome abnormalities induced during the proliferation of growth-factor-dependent TCLB cells in the thymus constitute a general mechanism by which neoplastic cells progress from growth-factor dependency to independency. PMID:6608730

  5. Coregulation of Epidermal Growth Factor Receptor\\/Human Epidermal Growth Factor Receptor 2 (HER2) Levels and Locations: Quantitative Analysis of HER2 Overexpression Effects1

    Microsoft Academic Search

    Bart S. Hendriks; Lee K. Opresko; H. Steven Wiley; Douglas Lauffenburger

    2003-01-01

    Elevated expression of human epidermal growth factor receptor 2 (HER2) is known to alter cell signaling and behavioral responses impli- cated in tumor progression. However, multiple diverse mechanisms may be involved in these overall effects, including signaling by HER2 itself, modulation of signaling by epidermal growth factor receptor (EGFR), and modification of trafficking dynamics for both EGFR and HER2. Because

  6. Dual epidermal growth factor receptor (EGFR)\\/insulin-like growth factor-1 receptor (IGF-1R) inhibitor: A novel approach for overcoming resistance in anticancer treatment

    Microsoft Academic Search

    Ruchi Tandon; Shweta Kapoor; Shireen Vali; V. Senthil; D. Nithya; R. Venkataramanan; Ashish Sharma; Anay Talwadkar; Abhijit Ray; Pradip K. Bhatnagar; Sunanda G. Dastidar

    2011-01-01

    Small molecule inhibitors of epidermal growth factor receptors (EGFR) have been found to show a good initial response in cancer patients but during the course of treatment, patients develop resistance after a few weeks of time. Development of secondary mutations or over-activation of insulin like growth factor (IGF-1R) pathway are a few of the several mechanisms proposed to explain the

  7. Hair growth-promoting effect of Carthamus tinctorius floret extract.

    PubMed

    Junlatat, Jintana; Sripanidkulchai, Bungorn

    2014-07-01

    The florets of Carthamus tinctorius L. have traditionally been used for hair growth promotion. This study aimed to examine the potential of hydroxysafflor yellow A-rich C.?tinctorius extract (CTE) on hair growth both in vitro and in vivo. The effect of CTE on cell proliferation and hair growth-associated gene expression in dermal papilla cells and keratinocytes (HaCaT) was determined. In addition, hair follicles from mouse neonates were isolated and cultured in media supplemented with CTE. Moreover, CTE was applied topically on the hair-shaved skin of female C57BL/6 mice, and the histological profile of the skin was investigated. C.?tinctorius floret ethanolic extract promoted the proliferation of both dermal papilla cells and HaCaT and significantly stimulated hair growth-promoting genes, including vascular endothelial growth factor and keratinocyte growth factor. In contrast, CTE suppressed the expression of transforming growth factor-?1 that is the hair loss-related gene. Furthermore, CTE treatment resulted in a significant increase in the length of cultured hair follicles and stimulated the growth of hair with local effects in mice. The results provided the preclinical data to support the potential use of CTE as a hair growth-promoting agent. PMID:24338940

  8. Promoted growth of murine hair follicles through controlled release of vascular endothelial growth factor.

    PubMed

    Ozeki, Makoto; Tabata, Yasuhiko

    2002-06-01

    The objective of this study is to investigate whether or not the controlled release of vascular endothelial growth factor (VEGF) is effective in promoting the hair follicle growth of mice in second anagen of hair cycle. VEGF was incorporated into a biodegradable collagen hydrogel for its controlled release. Following implantation of the collagen hydrogel incorporating 0 or 2 microg of VEGF and injection of 0 or 2 microg of VEGF in the solution form into the back subcutis of mice, the hair follicle growth was evaluated photometrically and histologically in terms of the skin color of reverse side of the implanted or injected site, the skin thickness, and the area occupied by hair follicle tissue. Ten days later, the skin color of mice implanted with the collagen hydrogel incorporating 2 microg of VEGF was significantly darker than that injected with 2 pg of VEGF. The collagen hydrogel incorporating VEGF increased the hair follicle area at the implanted site to a significantly greater extent than other agents while significant angiogenetic effect in the skin tissue was observed. VEGF-free, empty collagen hydrogels did not affect the skin darkness, hair follicle growth, and the angiogenesis. Moreover, the hair shaft length was significantly elongated by the collagen hydrogel incorporating VEGF, in marked contrast to other agents. Immunohistolchemicalstaining with proliferating cell nuclear antigen revealed that the collagen hydrogel incorporating VEGF promoted the proliferation of cells around the hair follicle more frequently than free VEGF. We concluded that the controlled release of VEGF more positively acted on the hair growth cycle of mice for hair growth than the injection of free VEGF. PMID:12013184

  9. Defects in TGF-beta signaling overcome senescence of mouse keratinocytes expressing v-Ha-ras.

    PubMed

    Tremain, R; Marko, M; Kinnimulki, V; Ueno, H; Bottinger, E; Glick, A

    2000-03-23

    Previous studies have shown that TGFbeta1 expression is upregulated in mouse keratinocytes infected with a v-rasHa retrovirus, although the functional significance of this has not been clear. Here we show that v-rasHa retrovirus transduced primary mouse keratinocytes undergo hyperproliferation followed by a TGFbeta1 dependent G1 growth arrest and senescence. The growth arrest is accompanied by a 15-fold increase in total TGFbeta1 secreted and a fourfold increase in secreted active TGFbeta1. When cultured in the presence of a neutralizing antibody to TGFbeta1, the senescence response is suppressed. Levels of the TGFbeta1 target p15ink4b increase during senescence as does association of this kinase inhibitor with cyclinD/cdk4 complexes. However, p16ink4a, p53 and p19ARF expression also increase during senescence. Genetic analysis shows that TGFbeta1 null and dominant negative TbetaBRII expressing v-rasHa keratinocytes resist the G1 growth arrest and do not senescence. This resistance is associated with low expression of p15ink4b and p16ink4a, constitutive Rb phosphorylation and high levels of cdk4 and cdk2 kinase activity. In contrast, inactivation of TGFbetabeta1 secretion or response does not block the induction of p53 and p19ARF, but the level of p21waf1, a p53 target gene, is reduced in cyclin D/cdk4 and cyclin E/cdk2 complexes. Thus, although multiple senescence pathways are activated in response to a ras oncogene, inactivation of TGFbeta1 secretion or response is sufficient to block the senescence program. Since v-rasHa transduced TGFbeta1-/- keratinocytes form squamous cell carcinomas following skin grafting, these results suggest that in mouse keratinocytes, defects in TGFbeta1 signaling accelerate malignant progression by overcoming oncogene induced replicative senescence. PMID:10763827

  10. Evidence for the identity of human scatter factor and human hepatocyte growth factor.

    PubMed Central

    Weidner, K M; Arakaki, N; Hartmann, G; Vandekerckhove, J; Weingart, S; Rieder, H; Fonatsch, C; Tsubouchi, H; Hishida, T; Daikuhara, Y

    1991-01-01

    Scatter factor (SF), a secretory protein of fibroblasts, dissociates and increases the motility of epithelial cells and may be involved in cell migration processes during embryogenesis and tumor progression. Hepatocyte growth factor (HGF), a protein isolated from serum of patients with liver failure, is a potent mitogen for hepatocytes and is thought to play a role in liver regeneration. Here we present structural and functional evidence that human SF and human HGF (and also the human lung fibroblast-derived mitogen) are identical proteins encoded by a single gene, since (i) no major difference could be found by protein sequencing, by cDNA analysis, and by immunological comparison and (ii) SF in fact acts as a hepatocyte growth factor--i.e., stimulates DNA synthesis of activity--i.e., dissociates and induces invasiveness of various epithelial cells. The human SF/HGF gene was localized to chromosome bands 7q11.2-21. These results have important consequences for further studies on the involvement of SF/HGF as a modulator of cellular growth and motility in embryonal, malignant, and regenerative processes. Images PMID:1831266

  11. Platelet-derived endothelial cell growth factor thymidine phosphorylase in tumour growth and response to therapy.

    PubMed Central

    Griffiths, L.; Stratford, I. J.

    1997-01-01

    Angiogenesis plays an important role in the growth and metastasis of solid tumours. Platelet-derived endothelial cell growth factor (PD-ECGF) is known to be chemotactic for endothelial cells in vitro and angiogenic in vivo. It is also known as gliostatin, a factor promoting neuronal survival, and thymidine phosphorylase (dThdPase), which catalyses the reversible phosphorylation of thymidine to thymine and 2-deoxyribose-1-phosphate. This enzymatic activity is critical for angiogenic activity. PD-ECGF protein is highly expressed in tumours compared with most normal tissues and has been correlated with tumour growth, invasion and metastasis in clinical studies. In addition, dThdPase activity (by inference PD-ECGF) has been found to be a major determinant of the toxicity of 5-fluorouracil and its prodrugs, which are extensively studied clinically as anti-cancer agents. This review attempts to summarize recent gains in understanding the nature, location and action of PD-ECGF and its specific relevance to tumour biology. PMID:9310231

  12. Targeting placental growth factor/neuropilin 1 pathway inhibits growth and spread of medulloblastoma.

    PubMed

    Snuderl, Matija; Batista, Ana; Kirkpatrick, Nathaniel D; Ruiz de Almodovar, Carmen; Riedemann, Lars; Walsh, Elisa C; Anolik, Rachel; Huang, Yuhui; Martin, John D; Kamoun, Walid; Knevels, Ellen; Schmidt, Thomas; Farrar, Christian T; Vakoc, Benjamin J; Mohan, Nishant; Chung, Euiheon; Roberge, Sylvie; Peterson, Teresa; Bais, Carlos; Zhelyazkova, Boryana H; Yip, Stephen; Hasselblatt, Martin; Rossig, Claudia; Niemeyer, Elisabeth; Ferrara, Napoleone; Klagsbrun, Michael; Duda, Dan G; Fukumura, Dai; Xu, Lei; Carmeliet, Peter; Jain, Rakesh K

    2013-02-28

    Medulloblastoma is the most common pediatric malignant brain tumor. Although current therapies improve survival, these regimens are highly toxic and are associated with significant morbidity. Here, we report that placental growth factor (PlGF) is expressed in the majority of medulloblastomas, independent of their subtype. Moreover, high expression of PlGF receptor neuropilin 1 (Nrp1) correlates with poor overall survival in patients. We demonstrate that PlGF and Nrp1 are required for the growth and spread of medulloblastoma: PlGF/Nrp1 blockade results in direct antitumor effects in vivo, resulting in medulloblastoma regression, decreased metastasis, and increased mouse survival. We reveal that PlGF is produced in the cerebellar stroma via tumor-derived Sonic hedgehog (Shh) and show that PlGF acts through Nrp1-and not vascular endothelial growth factor receptor 1-to promote tumor cell survival. This critical tumor-stroma interaction-mediated by Shh, PlGF, and Nrp1 across medulloblastoma subtypes-supports the development of therapies targeting PlGF/Nrp1 pathway. PMID:23452854

  13. Expression of epidermal growth factor and transforming growth factor ? in interfacial membranes retrieved at revision total hip arthroplasty

    PubMed Central

    Xu, J.; Ma, J.; Li, T.; Waris, E.; Alberty, A.; Santavirta, S.; Konttinen, Y.

    2000-01-01

    BACKGROUND—The interfacial membrane between bone and implant has been shown to be a key tissue in the process of aseptic loosening of total hip arthroplasty. The cells within the interfacial membrane produce numerous inflammatory mediators which, through complex mechanisms, cause periprosthetic osteolysis and aseptic loosening. Both epidermal growth factor (EGF) and transforming growth factor ? (TGF?) have similar biological functions. They have been found to stimulate bone resorption.?OBJECTIVE—To investigate the presence, cellular localisation, and extent of expression of EGF and TGF? in interfacial membrane retrieved from revision total hip arthroplasty and compare it with that in synovial membrane from primary total hip arthroplasty.?METHODS—Ten interfacial membranes and 10 synovial membranes were stained with avidin-biotin-peroxidase complex for EGF and TGF?. The staining process was done using the Lab Vision Autostainer. The results were measured by a semiautomatic VIDAS image analysis system.?RESULTS—Immunoreactivity for both EGF and TGF? was found in the endothelial cells of blood vessels, macrophages, and fibroblasts, both in interfacial membranes and synovial membranes. However, the number of EGF (980 (370)) and TGF? (1070 (360)) positive cells per mm2 was greater in interfacial membranes than in the synovial membranes (220 (200), 270 (100); p<0.01).?CONCLUSION—It is suggested that owing to their increased expression in interfacial membrane, EGF and TGF? may have an important pathogenetic role in stimulating periprosthetic bone resorption in aseptic loosening of total hip arthroplasty.?? PMID:11005785

  14. Expression of Vascular Endothelial Growth Factor and Epidermal Growth Factor Receptor in Pancreatic Ductal Adenocarcinomas, Neuroendocrine Tumours and Chronic Pancreatitis

    PubMed Central

    Angelescu, Radu; Burada, Florin; Angelescu, Cristina; Gheonea, Dan Ionut; Iordache, Sevasti?a; Mixich, Francisc; Ioana, Mihai; S?ftoiu, Adrian

    2013-01-01

    Objective: Angiogenesis is a crucial event for pancreatic carcinogenesis, and it also plays an important role in chronic pancreatitis. The aim of our study was to evaluate the mRNA expression of vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR) in chronic inflammatory or malignant pancreatic pathology in order to elucidate the differences in expression patterns and potential clinical implications. Methods: Thirty-five patients who had undergone endoscopic ultrasonography followed by endoscipic ultrasound-guided fine needle aspiration (EUS-FNA) of focal pancreatic masses were included in the study. VEGF and EGFR mRNA expression levels in the samples collected by EUS-FNA were analyzed using quantitative real-time polymerase chain reaction (PCR). Results: VEGF expression was detected in all chronic pancreatitis and adenocarcinoma samples and in only 62.5% of pancreatic neuroendocrine tumors. EGFR expression was detected in only 40% of the chronic pancreatitis cases, 76.9% of adenocarcinomas and in 50% of pancreatic neuroendocrine tumors. Both VEGF and EGFR mRNA levels were significantly higher in pancreatic ductal adenocarcinoma than those in normal tissue. VEGF expression inversely correlated with pancreatic ductal adenocarcinoma size, while EGFR expression was related to local invasiveness of adenocarcinoma. Conclusion: Both VEGF and EGFR mRNA expression in EUS-FNA samples may be used as a diagnostic marker associated with invasiveness in patients with pancreatic adenocarcinoma. PMID:24949370

  15. Expression of epidermal growth factor receptor, ezrin, hepatocyte growth factor, and c-Met in uveal melanoma: an immunohistochemical study.

    PubMed

    Mallikarjuna, Kandalam; Pushparaj, Vaijayanthi; Biswas, Jyotirmay; Krishnakumar, Subramanian

    2007-03-01

    The immunoreactivity of epidermal growth factor receptor (EGFR) ezrin, hepatocyte growth factor receptor (HGF), and c-Met was studied in 60 uveal melanomas and was correlated with clinicopathologic parameters. Metastases were diagnosed in the patients with uveal melanoma between 5 years and 8 years (median, 6.5 years) after enucleation. Using Kaplan-Meier statistical analysis, we found a significant association between high c-Met expression and death due to uveal melanoma (p < 0.03). EGFR was expressed in 18 of 60 (30%) tumors; ezrin was expressed in 30 of 60 (50%) tumors. Tumors with liver metastasis (n = 6) showed higher expression of c-Met (p = 0.0009) compared with the tumors with no extension/extrascleral extension without liver metastasis (groups A-45 and B-9). HGF was negative in all the six tumors that had liver metastasis. Further studies are required to understand the possible mechanism of ligand-independent c-Met activation in patients with uveal melanoma. PMID:17453948

  16. Childhood Exposure to Phthalates: Associations with Thyroid Function, Insulin-like Growth Factor I, and Growth

    PubMed Central

    Boas, Malene; Frederiksen, Hanne; Feldt-Rasmussen, Ulla; Skakkebæk, Niels E.; Hegedüs, Laszlo; Hilsted, Linda; Juul, Anders; Main, Katharina M.

    2010-01-01

    Background Phthalates are widely used chemicals, and human exposure is extensive. Recent studies have indicated that phthalates may have thyroid-disrupting properties. Objective We aimed to assess concentrations of phthalate metabolites in urine samples from Danish children and to investigate the associations with thyroid function, insulin-like growth factor I (IGF-I), and growth. Methods In 845 children 4–9 years of age, we determined urinary concentrations of 12 phthalate metabolites and serum levels of thyroid-stimulating hormone, thyroid hormones, and IGF-I. Results Phthalate metabolites were detected in all urine samples, of which monobutyl phthalate was present in highest concentration. Phthalate metabolites were negatively associated with serum levels of free and total triiodothyronine, although statistically significant primarily in girls. Metabolites of di(2-ethylhexyl) phthalate and diisononyl phthalate were negatively associated with IGF-I in boys. Most phthalate metabolites were negatively associated with height, weight, body surface, and height gain in both sexes. Conclusions Our study showed negative associations between urinary phthalate concentrations and thyroid hormones, IGF-I, and growth in children. Although our study was not designed to reveal the mechanism of action, the overall coherent negative associations between urine phthalate and thyroid and growth parameters may suggest causative negative roles of phthalate exposures for child health. PMID:20621847

  17. Up-regulation of TNF-alpha secretion by cigarette smoke is mediated by Egr-1 in HaCaT human keratinocytes.

    PubMed

    Jeong, Sang Hoon; Park, Jae Hong; Kim, Ji Na; Park, Yoon-Hee; Shin, Soon Young; Lee, Young Han; Kye, Young Chul; Son, Sang Wook

    2010-08-01

    Many epidemiologic studies have pointed to a significant association between cigarette smoking and inflammatory skin disease such as psoriasis. Cigarette smoke induces expression of regulators of inflammation such as interleukin (IL)-1, IL-6, IL-8 and tumor necrosis factor (TNF)-alpha. It was recently demonstrated that early growth response-1 (Egr-1) transcription factor is significantly up-regulated in the skin lesions of patients with psoriasis. The mechanism by which cigarette smoke extract (CSE) regulates inflammatory cytokine expression in keratinocyte was still unknown. The aim of this study was to investigate the signalling of CSE-induced Egr-1 expression and the role for Egr-1 in CSE-induced TNF-alpha expression. Cytotoxicity of CSE in HaCaT cells was measured by thiazolyl blue tetrazolium bromide (MTT) assay. CSE-induced Egr-1 expression was investigated by western blot, luciferase reporter assay and confocal microscopy. TNF-alpha expression was measured by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. Involvement of Egr-1 in CSE-induced TNF-alpha secretion was determined by using Egr-1 specific siRNA. CSE increases the Egr-1 expression, promoter activity and its nuclear translocation in human HaCaT keratinocytes. CSE activates mitogen-activated protein kinase (MAPK) pathways including extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK). Up-regulation of Egr-1 expression by CSE stimulation was found to be inhibited by an ERK and JNK but not p38 inhibitor. CSE increases TNF-alpha expression and secretion. This increase is mediated by CSE-induced Egr-1 expression. Our results showed that CSE induces Egr-1 expression via MAPK pathway in human keratinocytes and TNF-alpha expression by Egr-1. This pathway may contribute to the development of inflammatory disease such as psoriasis. PMID:20653771

  18. Platelet-derived growth factor BB secreted from osteoclasts acts as an osteoblastogenesis inhibitory factor.

    PubMed

    Kubota, Kazuishi; Sakikawa, Chisa; Katsumata, Mutsumi; Nakamura, Takemichi; Wakabayashi, Kenji

    2002-02-01

    Osteoclasts and osteoblasts are responsible for strict bone maintenance with a balance between bone formation and resorption by interacting with each other. Recently, it has been revealed that osteoblasts/stromal cells regulate differentiation of osteoclasts/hematopoietic cells by two factors, the receptor activator of nuclear factor-kappaB (NF-kappaB) ligand (RANKL) on the plasma membrane, and secreted osteoprotegerin (OPG). However, no factors have yet been reported by which osteoclasts/hematopoietic cells regulate osteoblasts/stromal cells. To elucidate the possibility of signal transduction from osteoclasts to osteoblasts, we studied the conditioned medium of mouse osteoclast-like myeloma cell line RAW264.7 treated with RANKL. We found that this medium contains a factor that inhibits differentiation of mouse osteoblast precursor-like cell line MC3T3-E1 to osteoblasts induced by bone morphogenetic protein 4 (BMP-4) and named this factor osteoblastogenesis inhibitory factor (OBIF). OBIF was purified by successive three-step chromatography by heparin affinity, anion exchange, and reversed-phase columns. Osteoblastogenesis inhibitory activity made one peak in each chromatography step, showing the factor is a single entity. Active fractions were loaded on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and bands of proteins were excised, digested by trypsin, and analyzed by liquid chromatography equipped with tandem mass spectrometry (LC/MS/MS). Consequently, we have identified this factor to be platelet-derived growth factor BB (PDGF BB) homodimer. Furthermore, this identification of PDGF BB as OBIF was confirmed by neutralization of the inhibitory activity of the medium with anti-PDGF antibody. These results show, for the first time, that osteoclasts regulate osteoblasts directly and suggest that PDGF BB is a key factor in bone remodeling. PMID:11811556

  19. Vascular Endothelial Growth Factor and Basic Fibroblast Growth Factor Induce Expression of CXCR4 on Human Endothelial Cells

    PubMed Central

    Salcedo, Rosalba; Wasserman, Ken; Young, Howard A.; Grimm, Michael C.; Howard, O. M. Zack; Anver, Miriam R.; Kleinman, Hynda K.; Murphy, William J.; Oppenheim, Joost J.

    1999-01-01

    The contribution of chemokines toward angiogenesis is currently a focus of intensive investigation. Certain members of the CXC chemokine family can induce bovine capillary endothelial cell migration in vitro and corneal angiogenesis in vivo, and apparently act via binding to their receptors CXCR1 and CXCR2. We used an RNAse protection assay that permitted the simultaneous detection of mRNA for various CXC chemokine receptors in resting human umbilical vein endothelial cells (HUVECs) and detected low levels of only CXCR4 mRNA. Stimulation of HUVECs with vascular endothelial growth factor (VEGF) or basic fibroblast growth factor (bFGF) up-regulated levels of only CXCR4 mRNA. CXCR4 specifically binds the chemokine stromal-derived factor-1? (SDF-1?). Competitive binding studies using 125I-labeled SDF-1? with Scatchard analysis indicated that VEGF or bFGF induced an average number of approximately 16,600 CXCR4 molecules per endothelial cell, with a Kd = 1.23 × 10?9 mol/L. These receptors were functional as HUVECs and human aorta endothelial cells (HAECs) migrated toward SDF-1?. Although SDF-1?-induced chemotaxis was inhibited by the addition of a neutralizing monoclonal CXCR4 antibody, endothelial chemotaxis toward VEGF was not altered; therefore, the angiogenic effect of VEGF is independent of SDF-1?. Furthermore, subcutaneous SDF-1? injections into mice induced formation of local small blood vessels that was accompanied by leukocytic infiltrates. To test whether these effects were dependent on circulating leukocytes, we successfully obtained SDF-1?-induced neovascularization from cross sections of leukocyte-free rat aorta. Taken together, our data indicate that SDF-1? acts as a potent chemoattractant for endothelial cells of different origins bearing CXCR4 and is a participant in angiogenesis that is regulated at the receptor level by VEGF and bFGF. PMID:10233851

  20. Endothelial Cell-Derived Basic Fibroblast Growth Factor: Synthesis and Deposition into Subendothelial Extracellular Matrix

    NASA Astrophysics Data System (ADS)

    Vlodavsky, Israel; Folkman, Judah; Sullivan, Robert; Fridman, Rafael; Ishai-Michaeli, Rivka; Sasse, Joachim; Klagsbrun, Michael

    1987-04-01

    Bovine aortic and corneal endothelial cells synthesize a growth factor that remains mostly cell-associated but can also be extracted from the subendothelial extracellular matrix (ECM) deposited by these cells. The endothelial cell-derived growth factors extracted from cell lysates and from the extracellular matrix appear to be structurally related to basic fibroblast growth factor by the criteria that they (i) bind to heparin-Sepharose and are eluted at 1.4-1.6 M NaCl, (ii) have a molecular weight of about 18,400, (iii) cross-react with anti-basic fibroblast growth factor antibodies when analyzed by electrophoretic blotting and immunoprecipitation, and (iv) are potent mitogens for bovine aortic and capillary endothelial cells. It is suggested that endothelium can store growth factors capable of autocrine growth promotion in two ways: by sequestering growth factor within the cell and by incorporating it into the underlying extracellular matrix.