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Sample records for keratinocyte growth factor

  1. 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

  2. Marked stimulation of growth and motility of human keratinocytes by hepatocyte growth factor

    SciTech Connect

    Matsumoto, K.; Hashimoto, K.; Yoshikawa, K.; Nakamura, T. )

    1991-09-01

    Effect of hepatocyte growth factor (HGF) on normal human epidermal keratinocytes cultured under conditions of low Ca2+ (0.1 mM, growth-promoting condition) and physiological Ca2+ (1.8 mM, differentiation-promoting condition) was investigated. In low Ca2+, HGF markedly enhanced the migration of keratinocytes while it suppressed cell growth and DNA synthesis in a dose-dependent manner. In contrast, HGF enhanced the migration, cell growth, and DNA synthesis of keratinocytes cultured under conditions of physiological Ca2+. The maximal stimulation of DNA synthesis (2.4-fold stimulation) in physiological Ca2+ was seen at 2.5-5 ng/ml HGF and the stimulatory effect of HGF was suppressed by transforming growth factor-beta 1. Analysis of the HGF receptor using 125I-HGF as a ligand showed that human keratinocytes expressed a single class of specific, saturable receptor for HGF in both low and physiological Ca2+ conditions, exhibiting a Kd = 17.3 pM and approximately 690 binding sites/cell under physiological Ca2+. Thus, HGF is a potent factor which enhances growth and migration of normal human keratinocytes under conditions of physiological Ca2+. HGF may play an important role in epidermal tissue repair as it enhances both the migration and growth of keratinocytes.

  3. Cortactin involvement in the keratinocyte growth factor and fibroblast growth factor 10 promotion of migration and cortical actin assembly in human keratinocytes

    SciTech Connect

    Ceccarelli, Simona; Cardinali, Giorgia; Aspite, Nicaela; Picardo, Mauro; Marchese, Cinzia; Torrisi, Maria Rosaria; Mancini, Patrizia . E-mail: patrizia.mancini@uniroma1.it

    2007-05-15

    Keratinocyte growth factor (KGF/FGF7) and fibroblast growth factor 10 (FGF10/KGF2) regulate keratinocyte proliferation and differentiation by binding to the tyrosine kinase KGF receptor (KGFR). KGF induces keratinocyte motility and cytoskeletal rearrangement, whereas a direct role of FGF10 on keratinocyte migration is not clearly established. Here we analyzed the motogenic activity of FGF10 and KGF on human keratinocytes. Migration assays and immunofluorescence of actin cytoskeleton revealed that FGF10 is less efficient than KGF in promoting migration and exerts a delayed effect in inducing lamellipodia and ruffles formation. Both growth factors promoted phosphorylation and subsequent membrane translocation of cortactin, an F-actin binding protein involved in cell migration; however, FGF10-induced cortactin phosphorylation was reduced, more transient and delayed with respect to that promoted by KGF. Cortactin phosphorylation induced by both growth factors was Src-dependent, while its membrane translocation and cell migration were blocked by either Src and PI3K inhibitors, suggesting that both pathways are involved in KGF- and FGF10-dependent motility. Furthermore, siRNA-mediated downregulation of cortactin inhibited KGF- and FGF10-induced migration. These results indicate that cortactin is involved in keratinocyte migration promoted by both KGF and FGF10.

  4. Expression and modulation of nerve growth factor in murine keratinocytes (PAM 212)

    SciTech Connect

    Tron, V.A.; Coughlin, M.D.; Jang, D.E.; Stanisz, J.; Sauder, D.N. )

    1990-04-01

    Nerve growth factor (NGF) is a polypeptide that is required for normal development and maintenance of the sympathetic and sensory nervous systems. Skin has been shown to contain relatively high amounts of NGF, which is in keeping with the finding that the quantity of NGF in a tissue is proportional to the extent of sympathetic innervation of that organ. Since the keratinocyte, a major cellular constituent of the skin, is known to produce other growth factors and cytokines, our experiments were designed to determine whether keratinocytes are a source of NGF. Keratinocyte-conditioned media from the keratinocyte cell line PAM 212 contained NGF-like activity, approximately 2-3 ng/ml, as detected by the neurite outgrowth assay. Freshly isolated BALB/c keratinocytes contained approximately 0.1 ng/ml. Using a cDNA probe directed against NGF, we demonstrated the presence of a 1.3-kb NGF mRNA in both PAM 212 and BALB/c keratinocytes. Since ultraviolet radiation (UV) is a potentially important modulating factor for cytokines in skin, we examined the effect of UV on NGF mRNA expression. Although UV initially inhibited the expression of keratinocyte NGF mRNA (4 h), by 24 h an induction of NGF mRNA was seen. The NGF signal could also be induced by phorbol esters. Thus, keratinocytes synthesize and express NGF, and its expression is modulated by UVB and phorbol esters.

  5. 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.

  6. Keratinocyte-derived T-cell growth factor: a T-cell growth factor functionally distinct from interleukin 2.

    PubMed Central

    Kupper, T S; Coleman, D L; McGuire, J; Goldminz, D; Horowitz, M C

    1986-01-01

    T-cell growth factor, more recently termed interleukin 2 (IL-2), is the product of activated T lymphocytes and is considered the principal trophic factor for T lymphocytes. The activity of IL-2 preparations is assessed by the degree to which they support the growth of various IL-2-dependent cell lines. We report that murine epidermal epithelial cells (keratinocytes) produce and release a factor that supports the growth of the helper-T-cell-derived, IL-2-dependent cell line HT-2. This substance, keratinocyte-derived T-cell growth factor (KTGF), does not support the growth of an IL-2-dependent cell line derived from cytotoxic T cells (line CTLL-2). This differential effect on IL-2-dependent cell lines is unique to KTGF. KTGF has an apparent molecular weight of 25,000-35,000 and has properties similar to those of conventional IL-2 by reversed-phase and gel-filtration HPLC analysis. However, even highly purified KTGF fails to stimulate the proliferation of CTLL-2 cells. The observation that epidermal epithelium produces a trophic factor for T lymphocytes may help explain the basis for preferential proliferation of T cells in the microenvironment of skin in certain dermatologic disorders. Further, it suggests that different IL-2-dependent T-cell lines may have distinct growth requirements and that non-lymphocyte cell types may produce factors capable of maintaining the growth of T cells. PMID:3520573

  7. Fibroblast Growth Factor-Peptide Improves Barrier Function and Proliferation in Human Keratinocytes After Radiation

    SciTech Connect

    Zhang Kunzhong; Tian Yeping; Yin Liangjie; Zhang Mei; Beck, Lisa A.; Zhang, Bingrong; Okunieff, Paul; Zhang Lurong; Vidyasagar, Sadasivan

    2011-09-01

    Purpose: Epidermal keratinocytes, which can be severely damaged after ionizing radiation (IR), are rapid turnover cells that function as a barrier, protecting the host from pathogenic invasion and fluid loss. We tested fibroblast growth factor-peptide (FGF-P), a small peptide derived from the receptor-binding domain of FGF-2, as a potential mitigator of radiation effects via proliferation and the barrier function of keratinocytes. Methods and Materials: Keratinocytes isolated from neonatal foreskin were grown on transwells. After being exposed to 0, 5, or 10 Gy IR, the cells were treated with a vehicle or FGF-P. The permeability of IR cells was assessed by using transepithelial electrical resistance (TEER) and a paracellular tracer flux of fluorescein isothiocyanate-conjugated bovine serum albumin (FITC-BSA) with Ussing chambers. The cell proliferation was measured with yellow tetrazolium salt (MTT) and tritiated thymidine ([{sup 3}H]-TdR) assays. The phosphorylation of extracellular signal-regulated kinases (ERK) was measured in an enzyme-linked immunosorbent (ELISA)-like assay, and the proteins related to tight junctions (TJ) and adherens junctions (AJ) were examined with Western blotting. We used a mouse model to assess the ability of FGF-P to promote the healing of skin {beta} burns created with a strontium applicator. Results: We found (1) FGF-P reduced the permeability of irradiated keratinocytes, as evidenced by increased TEER and decreased diffusion of FITC-BSA, both associated with the regulation of different proteins and levels of TJ and AJ; and (2) FGF-P enhanced the proliferation of irradiated keratinocytes, as evidenced by increased MTT activity and [{sup 3}H]-TdR incorporation, which was associated with activation of the ERK pathway; and (3) FGF-P promoted the healing of skin {beta} burns. Conclusions: FGF-P enhances the barrier function, including up-regulation of TJ proteins, increases proliferation of human keratinocytes, and accelerates the healing of skin {beta} burns. FGF-P is a promising mitigator that improves the proliferation and barrier function of keratinocytes after IR.

  8. Arsenite and insulin exhibit opposing effects on epidermal growth factor receptor and keratinocyte proliferative potential

    SciTech Connect

    Patterson, Timothy J.; Rice, Robert H. . E-mail: rhrice@ucdavis.edu

    2007-05-15

    Previous work has suggested that arsenic exposure contributes to skin carcinogenesis by preserving the proliferative potential of human epidermal keratinocytes, thereby slowing the exit of putative target stem cells into the differentiation pathway. To find a molecular basis for this action, present work has explored the influence of arsenite on keratinocyte responses to epidermal growth factor (EGF). The ability of cultured keratinocytes to found colonies upon passaging several days after confluence was preserved by arsenite and EGF in an additive fashion, but neither was effective when the receptor tyrosine kinase activity was inhibited. Arsenite prevented the loss of EGF receptor protein and phosphorylation of tyrosine 1173, preserving its capability to signal. The level of nuclear {beta}-catenin was higher in cells treated with arsenite and EGF in parallel to elevated colony forming ability, and expression of a dominant negative {beta}-catenin suppressed the increase in both colony forming ability and yield of putative stem cells induced by arsenite and EGF. As judged by expression of three genes regulated by {beta}-catenin, this transcription factor had substantially higher activity in the arsenite/EGF-treated cells. Trivalent antimony exhibited the same effects as arsenite. A novel finding is that insulin in the medium induced the loss of EGF receptor protein, which was largely prevented by arsenite exposure.

  9. Keratinocytic Vascular Endothelial Growth Factor as a Novel Biomarker for Pathological Skin Condition

    PubMed Central

    Bae, Ok-Nam; Noh, Minsoo; Chun, Young-Jin; Jeong, Tae Cheon

    2015-01-01

    Skin is an emerging target tissue in pharmaceutical and cosmetic science. Safety assessment for dermal toxicity is a critical step for development of topically applicable pharmaceutical agents and ingredients in cosmetics. Urgent needs exist to set up toxicity testing methods for dermal safety, and identification of novel biomarkers for pathological cutaneous alteration is highly required. Here we will discuss if vascular endothelial growth factor (VEGF) has a potential as a biomarker for dermal impairment. Experimental and clinical evidences for induction of keratinocytic VEGF under pathological conditions will be reviewed. PMID:25593638

  10. Acrolein induces activation of the epidermal growth factor receptor of human keratinocytes for cell death.

    PubMed

    Takeuchi, K; Kato, M; Suzuki, H; Akhand, A A; Wu, J; Hossain, K; Miyata, T; Matsumoto, Y; Nimura, Y; Nakashima, I

    2001-01-01

    Acrolein, which is a highly reactive formaldehyde generated by lipid peroxidation, can affect skin and cause various disorders. The effect of exposure of human keratinocytes to acrolein on cell surface-oriented signal transduction into cells was examined. Incubation of human keratinocytes with a relatively low concentration (50 microM) of acrolein caused a prompt and selective induction of tyrosine phosphorylation of the epidermal growth factor receptor (EGFR) as a 180-kDa molecule during the period from 5-30 min after the start of incubation. This early event was followed by an increase in the density and number of phosphotyrosine-containing proteins during the period from 60-120 min after the start of incubation. The catalytic activity of EGFR as measured by the levels of autophorphorylation and phosphorylation of an exogenously added substrate, casein, in in vitro kinase assay, greatly increased as early as 1 min after the start of incubation and then decreased gradually 30 min later. MAP family kinases, including ERK, JNK, and p38 kinase, and the potentially downstream transcription factor c-Jun were all promoted for phosphorylation/activation during a period of 5-30 min. Selective prompt phosphorylation/activation of EGFR followed by phosphorylation of MAP family kinases and c-Jun and their blockade by a specific EGFR inhibitor, AG1478, suggested that activation of EGFR is the major, and possibly single, cell surface element for intracellular signal transduction in acrolein-treated cells. Incubation of human keratinocytes with 50 microM of acrolein induced atypical apoptosis with morphologic apoptotic features with low-grade oligonucleoside-sized DNA fragmentation. Partial inhibition of such a cytopathic effect of acrolein on human keratinocytes by preincubation with AG1478 suggests the involvement of an EGFR-mediated signal pathway for atypical apoptosis. These results provide new information on acrolein-induced cell surface-oriented signal transduction to human keratinocytes, and this information may be useful for understanding the pathogenesis of a number of skin diseases in response to environmental acrolein and acrolein-generating ultraviolet irradiation. PMID:11329622

  11. A keratinocyte growth factor receptor-derived peptide antagonist identifies part of the ligand binding site.

    PubMed

    Bottaro, D P; Fortney, E; Rubin, J S; Aaronson, S A

    1993-05-01

    Keratinocyte growth factor (KGF) is a fibroblast growth factor (FGF) family member that acts specifically on cells of epithelial origin. Its receptor (KGFR) is a membrane-spanning tyrosine kinase, which also binds acidic FGF (aFGF) with equally high affinity, and basic FGF (bFGF) with much lower affinity. The KGFR is encoded by the bek/FGFR-2 gene, whose alternative transcript specifies a receptor with high affinity for aFGF and bFGF, but no detectable binding of KGF. The only structural difference between these two receptors is a 49-amino acid segment in the extracellular domain that is determined by single alternative exons. We report that a synthetic peptide (NH2-His199...Tyr223-COOH) corresponding to part of the predicted sequence of the KGFR alternative exon blocks KGF mitogenic activity and the interaction between KGF and its receptor. The peptide also blocks the interaction between KGF and a neutralizing monoclonal antibody raised against this growth factor. These results demonstrate that the peptide binds directly and specifically to KGF and argue that this region of the receptor constitutes part or all of the KGF binding site. PMID:8387485

  12. Generation and characterization of monoclonal antibodies to human keratinocyte growth factor receptor.

    PubMed

    Wei, Ping; Zhan, Jinghui; Liu, Shuying; Chang, David; Haldankar, Raj; Burkhardt, Kim; Crouse, Jill; Hui, John; Juan, Todd; Talvenheimo, Jane; Kim, Helen; Li, Luke; Boone, Tom; Borges, Luis

    2006-06-01

    Keratinocyte growth factor receptor (KGFR) and fibroblast growth factor receptor (FGFR) 2c share identical amino acid sequences, except for a 46-amino acid domain in the extracellular region. Monoclonal antibodies (MAbs) specific to KGFR have not been reported nor are commercially available. In this study, we generated murine MAbs specific to KGFR in non-obese diabetic (NOD) mice using a modified Repeated Immunizations at Multiple Sites (RIMMS) technology. Stable cell lines expressing the full-length human KGFR or FGFR2c were produced to facilitate the identification of KGFR-specific MAbs. Following the initial screening of hybridoma clones with a fluorescence-based, confocal cell detection method and ELISA, KGFR-specific MAbs were selected and confirmed by flow cytometry and Western blot analyses. Antagonistic MAbs were identified using a cell-based functional assay. These KGFR MAbs will be important reagents for studying the biological function and tissue distribution of this receptor in normal and pathological conditions. PMID:16796457

  13. Transforming growth factor-? enhances invasion and metastasis in Ras-transfected human malignant epidermal keratinocytes.

    PubMed

    Davies, Maria; Prime, Stephen S; Eveson, John W; Price, Nicky; Ganapathy, Anu; D'Mello, Anita; Paterson, Ian C

    2012-04-01

    Transforming growth factor-? (TGF-?) is known to act as a tumour suppressor early in carcinogenesis, but then switches to a pro-metastatic factor in some late stage cancers. However, the actions of TGF-? are context dependent, and it is currently unclear how TGF-? influences the progression of human squamous cell carcinoma (SCC). This study examined the effect of overexpression of TGF-?1 or TGF-?2 in Ras-transfected human malignant epidermal keratinocytes that represent the early stages of human SCC. In vitro, the proliferation of cells overexpressing TGF-?1 or TGF-?2 was inhibited by exogenous TGF-?1; cells overexpressing TGF-?1 also grew more slowly than controls, but the growth rate of TGF-?2 overexpressing cells was unaltered. However, cells that overexpressed either TGF-?1 or TGF-?2 were markedly more invasive than controls in an organotypic model of SCC. The proliferation of the invading TGF-?1 overexpressing cells in the organotypic assays was higher than controls. Similarly, tumours formed by the TGF-?1 overexpressing cells following transplantation to athymic mice were larger than tumours formed by control cells and proliferated at a higher rate. Our results demonstrate that elevated expression of either TGF-?1 or TGF-?2 in cells that represent the early stages in the development of human SCC results in a more aggressive phenotype. PMID:22414291

  14. The role of chronic inflammation in cutaneous fibrosis: fibroblast growth factor receptor deficiency in keratinocytes as an example.

    PubMed

    Meyer, Michael; Müller, Anna-Katharina; Yang, Jingxuan; ?ulcová, Jitka; Werner, Sabine

    2011-12-01

    Fibrosis is associated with a variety of skin diseases and causes severe aesthetic and functional impairments. Functional studies in rodents, together with clinical observations, strongly suggest a crucial role of chronic injury and inflammation in the pathogenesis of fibrotic diseases. The phenotype of mice lacking fibroblast growth factor (FGF) receptors 1 and 2 in keratinocytes supports this concept. In these mice, a defect in keratinocytes alone initiated an inflammatory response, which in turn caused keratinocyte hyperproliferation and dermal fibrosis. As the mechanism underlying this phenotype, we identified a loss of FGF-induced expression of claudins and occludin, which caused abnormalities in tight junctions with concomitant deficits in epidermal barrier function. This resulted in severe transepidermal water loss and skin dryness. In turn, activation of keratinocytes and epidermal ?? T cells occurred, which produced IL-1 family member 8 and S100A8 and S100A9. These cytokines attracted immune cells and activated fibroblasts, resulting in a double paracrine loop through production of keratinocyte mitogens by dermal cells. In addition, a profibrotic response was induced in fibroblasts. Our results highlight the importance of an intact epidermal barrier for the prevention of inflammation and fibrosis and the role of chronic inflammation in the pathogenesis of fibrotic diseases. PMID:22076327

  15. 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

  16. Inhibition of sup 125 I-epidermal growth factor binding to cultured keratinocytes by antiproliferative molecules gamma interferon, cyclosporin A, and transforming growth factor-beta

    SciTech Connect

    Nickoloff, B.J.; Mitra, R.S. )

    1989-12-01

    The growth of cultured human keratinocytes (KC) is inhibited by gamma interferon (IFN-gamma), cyclosporin A and transforming growth factor-beta, but not by tumor necrosis factor. When these antiproliferative molecules were added to KC they induced a concentration and time-dependent inhibition of {sup 125}I-epidermal growth factor (I-EGF) binding. These anti-proliferative molecules primarily reduced the number of binding sites by approximately 25%-50% without affecting the binding affinity. Tumor necrosis factor did not influence the ligand binding by I-EGF. In parallel with the ability of the antiproliferative molecules to inhibit I-EGF binding, there was an increase in transforming growth factor-alpha production. These results suggest that several different antiproliferative molecules may share a common mechanism to inhibit cell growth by reducing I-EGF binding to KC.

  17. Keratinocyte Growth Factor Promotes Epithelial Survival and Resolution in a Human Model of Lung Injury

    PubMed Central

    Shyamsundar, Murali; McAuley, Daniel F.; Ingram, Rebecca J.; Gibson, David S.; McKeown, Scott T.; Edwards, Alex; Taggart, Cliff; Elborn, Joseph S.; Calfee, Carolyn S.; Matthay, Michael A.

    2014-01-01

    Rationale: Increasing epithelial repair and regeneration may hasten resolution of lung injury in patients with the acute respiratory distress syndrome (ARDS). In animal models of ARDS, keratinocyte growth factor (KGF) reduces injury and increases epithelial proliferation and repair. The effect of KGF in the human alveolus is unknown. Objectives: To test whether KGF can attenuate alveolar injury in a human model of ARDS. Methods: Volunteers were randomized to intravenous KGF (60 ?g/kg) or placebo for 3 days, before inhaling 50 ?g LPS. Six hours later, subjects underwent bronchoalveolar lavage (BAL) to quantify markers of alveolar inflammation and cell-specific injury. Measurements and Main Results: KGF did not alter leukocyte infiltration or markers of permeability in response to LPS. KGF increased BAL concentrations of surfactant protein D, matrix metalloproteinase (MMP)-9, IL-1Ra, granulocyte-macrophage colony–stimulating factor (GM-CSF), and C-reactive protein. In vitro, BAL fluid from KGF-treated subjects inhibited pulmonary fibroblast proliferation, but increased alveolar epithelial proliferation. Active MMP-9 increased alveolar epithelial wound repair. Finally, BAL from the KGF-pretreated group enhanced macrophage phagocytic uptake of apoptotic epithelial cells and bacteria compared with BAL from the placebo-treated group. This effect was blocked by inhibiting activation of the GM-CSF receptor. Conclusions: KGF treatment increases BAL surfactant protein D, a marker of type II alveolar epithelial cell proliferation in a human model of acute lung injury. Additionally, KGF increases alveolar concentrations of the antiinflammatory cytokine IL-1Ra, and mediators that drive epithelial repair (MMP-9) and enhance macrophage clearance of dead cells and bacteria (GM-CSF). Clinical trial registered with ISRCTN 98813895. PMID:24716610

  18. 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

  19. Keratinocyte growth factor-2 inhibits bacterial infection with Pseudomonas aeruginosa pneumonia in a mouse model.

    PubMed

    Feng, Nana; Wang, Qin; Zhou, Jian; Li, Jing; Wen, Xiaoxing; Chen, Shujing; Zhu, Zhenhua; Bai, Chunxue; Song, Yuanlin; Li, Huayin

    2016-01-01

    To determine protective effects of concurrent administration of Keratinocyte growth factor-2 (KGF-2) with Pseudomonas aeruginosa (P. aeruginosa) inoculation on the induced pneumonia. KGF-2 (5 mg/kg) was concurrently administered into the left lobe of 55 mice with P. aeruginosa PAO1 (5 × 10(6) CFU, half-lethal dose); 55 mice in the control group were concurrently administered PBS with the PAO1. We detected and analyzed: body temperature; amount of P. aeruginosa in homogenates; count of total number of nucleated cells and of mononuclear macrophages; protein concentration in bronchoalveolar lavage fluid (BALF); lung wet-to-dry weight ratio; cytokines in BALF and blood; and lung morphology. To study survival rate, concurrent administration of KGF-2 (experimental group) versus PBS (control) with a lethal dose of PAO1 (1 × 10(7) CFU was performed, and survivorship was documented for 7 days post-inoculation. The bacterial CFU in lung homogenates was significantly decreased in the KGF-2 group compared to the control group. There were significantly more mononuclear macrophages in the BALF from the KGF-2 group than from the control group (p < 0.05). KGF-2 increased the surfactant protein and GM-CSF mRNA in lung at 6 h and 72 h after inoculation. Significant reduction of lung injury scores, protein concentrations, lung wet-to-dry weight ratio, and IL-6 and TNF-? levels was noted in the KGF-2 treated rats at 72 h after inoculation (p < 0.05). The 7-day survival rate of the KGF-2 group was significantly higher than that of the control group (p < 0.05). Concurrent administration of KGF-2 facilitates the clearance of P. aeruginosa from the lungs, attenuates P. aeruginosa-induced lung injury, and extends the 7-day survival rate in mice model with P. aeruginosa pneumonia. PMID:26617350

  20. Angiopoietin-related growth factor (AGF) supports adhesion, spreading, and migration of keratinocytes, fibroblasts, and endothelial cells through interaction with RGD-binding integrins

    SciTech Connect

    Zhang Yueqing; Hu Xiaobo; Tian Ruiyang; Wei Wangui; Hu Wei; Chen Xia; Han Wei; Chen Huayou; Gong Yi . E-mail: ygong@sibs.ac.cn

    2006-08-18

    Angiopoietin-related growth factor (AGF) is a newly identified member of angiopoietin-related proteins (ARPs)/angiopoietin-like proteins (Angptls). AGF has been considered as a novel growth factor in accelerating cutaneous wound healing, as it is capable of stimulating keratinocytes proliferation as well as angiogenesis. But in our paper, we demonstrate that AGF stimulates keratinocytes proliferation only at high protein concentration, however, it can potently promote adhesion, spreading, and migration of keratinocytes, fibroblasts, and endothelial cells. Furthermore, we confirm that the adhesion and migration cellular events are mediated by RGD-binding integrins, most possibly the {alpha}{sub v}-containing integrins, by in vitro inhibition assays using synthetic competitive peptides. Our results strongly suggest that AGF is an integrin ligand as well as a mitogenic growth factor and theoretically participates in cutaneous wound healing in a more complex mechanism.

  1. Myofibroblast keratinocyte growth factor reduces tight junctional integrity and increases claudin-2 levels in polarized Caco-2 cells

    PubMed Central

    Kim, Tae Il; Poulin, Emily J.; Blask, Elliot; Bukhalid, Raghida; Whitehead, Robert H.; Franklin, Jeffrey L.; Coffey, Robert J.

    2013-01-01

    The colonic epithelium is composed of a polarized monolayer sheathed by a layer of pericryptal myofibroblasts (PCMFs). We mimicked these cellular compartments in vitro to assess the effects of paracrine-acting PCMF-derived factors on tight junction (TJ) integrity, as measured by transepithelial electrical resistance (TER). Co-culture with 18Co PCMFs, or basolateral administration of 18Co conditioned medium (CM), significantly reduced TER of polarized Caco-2 cells. Amongst candidate paracrine factors, only keratinocyte growth factor (KGF) reduced Caco-2 TER; basolateral KGF treatment led to time- and concentration-dependent increases in claudin-2 levels. We also demonstrate amphiregulin (AREG), produced largely by Caco-2 cells, increased claudin-2 levels, leading to epidermal growth factor receptor-mediated TER reduction. We propose that colonic epithelial TJ integrity can be modulated by paracrine KGF and autocrine AREG through increased claudin-2 levels. KGF-regulated claudin-2 induction may have implications for inflammatory bowel disease, where both KGF and claudin-2 are upregulated. PMID:22946653

  2. Nerve growth factor regulates the expression of vascular endothelial growth factor in human HaCaT keratinocytes via PI3K/mTOR pathway.

    PubMed

    Zhang, J; Ma, W Y

    2014-01-01

    Decades of research have provided the data to confirm the hypothesis that there is bidirectional communication between the central nervous system and the immune system in psoriasis pathogenesis, but the contribution of the cutaneous neural system remains underexplored. In this study, we evaluated the molecular mechanisms by which nerve growth factor (NGF) regulates hypoxia-inducible factor-1? (HIF-1?) and vascular endothelial growth factor (VEGF) production. The mRNA and protein levels of VEGF secretion from HaCaT cells by NGF were increased in a concentration-dependent manner. In addition, the NGF- induced increase in VEGF is accompanied by an increase in HIF-1?, but not HIF-2? or HIF-1?. However, this increase is abrogated by pretreatment with a mammalian target of rapamycin (mTOR) inhibitor rapamycin. Pharmacologic inhibitors of the Trk tyrosine kinase, PI-3 kinase, and mTOR pathways prevent NGF-stimulated increases in HIF-1? and VEGF. Mutation of the siRNA-mediated silencing of HIF-1? expression blocks NGF-induced increases in VEGF transcription. Our study indicates that NGF regulates the expression of VEGF through the PI3K/mTOR signaling pathway in human HaCaT keratinocytes. PMID:24615084

  3. Transactivation of involucrin, a marker of differentiation in keratinocytes, by lens epithelium-derived growth factor (LEDGF).

    PubMed

    Kubo, E; Fatma, N; Sharma, P; Shinohara, T; Chylack, L T; Akagi, Y; Singh, D P

    2002-07-26

    Human involucrin (hINV), first appears in the cytosol of keratinocytes and ultimately cross-linked to membrane proteins via transglutaminase and forms a protective barrier as an insoluble envelope beneath the plasma membrane. Although the function and evolution of involucrin is known, the regulation of its gene expression is not well understood. An analysis of the hINV gene sequence, upstream of the transcription start site (-534 to +1 nt) revealed the presence of potential sites for binding of lens epithelium-derived growth factor (LEDGF); stress response element (STRE; A/TGGGGA/T) and heat shock element (HSE; nGAAn). We reported earlier that LEDGF activates stress-associated genes by binding to these elements and elevates cellular resistance to various stresses. Here, gel-shift and super-shift assays confirm the binding of LEDGF to the DNA fragments containing HSEs and STREs that are present in the involucrin gene promoter. Furthermore, hINV promoter linked to CAT reporter gene, cotransfected in human corneal simian virus 40-transformed keratinocytes (HCK), was transactivated by LEDGF significantly. In contrast, the activity of hINV promoter bearing mutations at the WT1 (containing HSE and STRE), WT2 (containing STRE) and WT3 (containing STRE) binding sites was diminished. In addition, in HCK cell over-expressing LEDGF, the levels of hINV mRNA and hINV protein are increased by four to five-fold. LEDGF is inducible to oxidants. Cells treated with 12-O-tetradecanoyl-phorbol-13-acetate (TPA), known to stimulate production of H(2)O(2), showed higher levels of LEDGF mRNA. Furthermore, our immunohistochemical studies revealed that hINV protein is found in the cytoplasm of HCK cells over-expressing LEDGF, but not detectable in the normal HCK cells or HCK cells transfected with vector. This regulation appears to be physiologically important, as over-expression of HCK with LEDGF increases the expression of the endogenous hINV gene and may provide new insight to understand the molecular mechanism of transcriptional regulation of this gene. LEDGF may play an important role in establishing an important barrier in corneal keratinocytes by maintaining epidermal turn-over rate, and protecting HCKs against stress. PMID:12126624

  4. ?-Adducin siRNA disruption of the spectrin-based cytoskeleton in differentiating keratinocytes prevented by calcium acting through calmodulin/epidermal growth factor receptor/cadherin pathway.

    PubMed

    Wu, Jianghong; Masci, Paul P; Chen, Chenfeng; Chen, Jiezhong; Lavin, Martin F; Zhao, Kong-Nan

    2015-01-01

    Here, we report that siRNA transfection of ?-adducin significantly disrupted the spectrin-based cytoskeleton and cytoskeletal arrangements of both ?-adducin and PKC? by substantially inhibiting the expression of ?-adducin, spectrin and PKC? proteins in differentiating keratinocytes. However, extracellular Ca2+ treatment blocked the inhibitory effects of the ?-adducin siRNA. Ca2+ also prevented the significant down-regulation of two differentiation markers involucrin and K1/10 and the distinct up-regulation of proliferation marker K14 in ?-adducin siRNA transfected keratinocytes. In addition, ?-adducin knockdown resulted in a substantial reduction of epidermal growth factor receptor (EGFR), cadherin and ?-catenin and enhanced phosphorylation of EGFR on tyrosine 1173 and Ca2+ prevented these changes. Furthermore, Ca2+ blocked the inhibitory effects of ?-adducin siRNA on the expression of calmodulin, phosphorylated-calmodulin (P-CaM((Tyr138))) and myristoylated alanine-rich C-kinase substrate (MARCKS) in keratinocytes. Co-immunoprecipitation studies further revealed that calmodulin, not MARCKS, strongly interacted with EGFR, cadherin and ?-catenin. Our data suggest that Ca2+ plays an important role in regulating the expression and function of ?-adducin to sustain normal organization of the spectrin-based cytoskeleton and the differentiation properties in keratinocytes through the calmodulin/EGFR/cadherin signaling pathway. PMID:25305142

  5. 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

  6. Interferon regulatory factor 6 regulates keratinocyte migration

    PubMed Central

    Biggs, Leah C.; Naridze, Rachelle L.; DeMali, Kris A.; Lusche, Daniel F.; Kuhl, Spencer; Soll, David R.; Schutte, Brian C.; Dunnwald, Martine

    2014-01-01

    ABSTRACT Interferon regulatory factor 6 (Irf6) regulates keratinocyte proliferation and differentiation. In this study, we tested the hypothesis that Irf6 regulates cellular migration and adhesion. Irf6-deficient embryos at 10.5?days post-conception failed to close their wound compared with wild-type embryos. In vitro, Irf6-deficient murine embryonic keratinocytes were delayed in closing a scratch wound. Live imaging of the scratch showed deficient directional migration and reduced speed in cells lacking Irf6. To understand the underlying molecular mechanisms, cell–cell and cell–matrix adhesions were investigated. We show that wild-type and Irf6-deficient keratinocytes adhere similarly to all matrices after 60?min. However, Irf6-deficient keratinocytes were consistently larger and more spread, a phenotype that persisted during the scratch-healing process. Interestingly, Irf6-deficient keratinocytes exhibited an increased network of stress fibers and active RhoA compared with that observed in wild-type keratinocytes. Blocking ROCK, a downstream effector of RhoA, rescued the delay in closing scratch wounds. The expression of Arhgap29, a Rho GTPase-activating protein, was reduced in Irf6-deficient keratinocytes. Taken together, these data suggest that Irf6 functions through the RhoA pathway to regulate cellular migration. PMID:24777480

  7. Interferon regulatory factor 6 regulates keratinocyte migration.

    PubMed

    Biggs, Leah C; Naridze, Rachelle L; DeMali, Kris A; Lusche, Daniel F; Kuhl, Spencer; Soll, David R; Schutte, Brian C; Dunnwald, Martine

    2014-07-01

    Interferon regulatory factor 6 (Irf6) regulates keratinocyte proliferation and differentiation. In this study, we tested the hypothesis that Irf6 regulates cellular migration and adhesion. Irf6-deficient embryos at 10.5?days post-conception failed to close their wound compared with wild-type embryos. In vitro, Irf6-deficient murine embryonic keratinocytes were delayed in closing a scratch wound. Live imaging of the scratch showed deficient directional migration and reduced speed in cells lacking Irf6. To understand the underlying molecular mechanisms, cell-cell and cell-matrix adhesions were investigated. We show that wild-type and Irf6-deficient keratinocytes adhere similarly to all matrices after 60?min. However, Irf6-deficient keratinocytes were consistently larger and more spread, a phenotype that persisted during the scratch-healing process. Interestingly, Irf6-deficient keratinocytes exhibited an increased network of stress fibers and active RhoA compared with that observed in wild-type keratinocytes. Blocking ROCK, a downstream effector of RhoA, rescued the delay in closing scratch wounds. The expression of Arhgap29, a Rho GTPase-activating protein, was reduced in Irf6-deficient keratinocytes. Taken together, these data suggest that Irf6 functions through the RhoA pathway to regulate cellular migration. PMID:24777480

  8. Severe ulceration with impaired induction of growth factors and cytokines in keratinocytes after trichloroacetic acid application on TRPV1-deficient mice.

    PubMed

    Li, Hong-jin; Kanazawa, Nobuo; Kimura, Ayako; Kaminaka, Chikako; Yonei, Nozomi; Yamamoto, Yuki; Furukawa, Fukumi

    2012-01-01

    Transient receptor potential vanilloid 1 (TRPV1) is a highly polymodal TRP channel activated by various stimuli, including capsaicin, heat and acids. TRPV1 expression can be detected widely but is highest in sensory neurons and its activation alerts the body to noxious signals via neurogenic pain. Although TRPV1 is reportedly localized in the epidermis, it remains unclear how TRPV1 is involved in the chemical peeling processes with cytotoxic acids. Therefore, in this study, the role of TRPV1 on the effects of trichloroacetic acid (TCA) peeling was assessed using TRPV1-deficient mice. Following the confirmation of TRPV1 expression in murine keratinocytes with reverse transcription-polymerase chain reaction and immunohistochemistry, the effects of TCA on TRPV1-deficient mouse skin were compared with those on wild-type mouse skin. Our results indicated that TRPV1 expression was not required for TCA-induced DNA damage, as shown by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling, but was indispensable for the TCA-induced production of distinct growth factors and cytokines by keratinocytes. Ulceration after TCA peeling was actually more severe in the absence of TRPV1, suggesting that the TRPV1-mediated epidermal production of growth factors and cytokines affected the damaging and healing processes of TCA-peeled skin to induce rejuvenation. PMID:22858856

  9. A novel signaling pathway of tissue kallikrein in promoting keratinocyte migration: Activation of proteinase-activated receptor 1 and epidermal growth factor receptor

    SciTech Connect

    Gao, Lin; Chao, Lee; Chao, Julie

    2010-02-01

    Biological functions of tissue kallikrein (TK, KLK1) are mainly mediated by kinin generation and subsequent kinin B2 receptor activation. In this study, we investigated the potential role of TK and its signaling pathways in cultured human keratinocyte migration and in a rat skin wound healing model. Herein, we show that TK promoted cell migration and proliferation in a concentration- and time-dependent manner. Inactive TK or kinin had no significant effect on cell migration. Interestingly, cell migration induced by active TK was not blocked by icatibant or L-NAME, indicating an event independent of kinin B2 receptor and nitric oxide formation. TK's stimulatory effect on cell migration was inhibited by small interfering RNA for proteinase-activated receptor 1 (PAR{sub 1}), and by PAR{sub 1} inhibitor. TK-induced migration was associated with increased phosphorylation of epidermal growth factor receptor (EGFR) and extracellular signal-regulated kinase (ERK), which was blocked by inhibition of protein kinase C (PKC), Src, EGFR and ERK. TK-induced cell migration and EGFR phosphorylation were blocked by metalloproteinase (MMP) inhibitor, heparin, and antibodies against EGFR external domain, heparin-binding EGF-like growth factor (HB-EGF) and amphiregulin (AR). Local application of TK promoted skin wound healing in rats, whereas icatibant and EGFR inhibitor blocked TK's effect. Skin wound healing was further delayed by aprotinin and neutralizing TK antibody. This study demonstrates a novel role of TK in skin wound healing and uncovers new signaling pathways mediated by TK in promoting keratinocyte migration through activation of the PAR{sub 1}-PKC-Src-MMP pathway and HB-EGF/AR shedding-dependent EGFR transactivation.

  10. 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

  11. Estradiol Regulation of Constitutive and Keratinocyte Growth Factor-induced CCL20 and CXCL1 Secretion by Mouse Uterine Epithelial Cells

    PubMed Central

    Haddad, Severina N.; Wira, Charles R.

    2014-01-01

    Problem Estradiol can directly affect epithelial cells or indirectly affect epithelial cells via stromal fibroblast secretion of growth factors, such as keratinocyte growth factor (KGF). The purpose of the present study was to determine if estradiol regulates constitutive as well as KGF-induced uterine epithelial cell secretion of CCL20 and CXCL1. Method of Study Freshly isolated and polarized uterine epithelial cells from Balb/c mice were cultured with estradiol in the presence or absence of KGF. CCL20 and CXCL1 were measured by ELISA. Results Estradiol inhibited CCL20 secretion by freshly isolated and polarized uterine epithelial cells in the presence or absence of KGF. Unexpectedly, it enhanced KGF-induced CXCL1 secretion beyond that seen with KGF alone. Estradiol increased CXCL1 secretion at 24 hours and inhibited CCL20 at 48 hours. The effects of estradiol are specific in that progesterone, cortisol, dihydrotestosterone, and aldosterone had no effect on either CCL20 or CXCL1 secretion. The inhibitory effect of estradiol on CCL20 secretion was reversed with ICI 182,780, an estrogen-receptor antagonist, indicating that this effect is estrogen receptor-mediated. Conclusions Our data indicate that estradiol is important in regulating the effects of KGF on mouse uterine epithelial cell secretion of CCL20 and CXCL1. PMID:24807244

  12. Storage Stability of Keratinocyte Growth Factor-2 in Lyophilized Formulations: Effects of Formulation Physical Properties and Protein Fraction at the Solid-Air Interface

    PubMed Central

    Devineni, Dilip; Gonschorek, Christoph; Cicerone, Marcus T; Xu, Yemin; Carpenter, John F.; Randolph, Theodore W.

    2014-01-01

    Lyophilized formulations of keratinocyte growth factor-2 (KGF-2) were prepared with a range of disaccharide (sucrose or trehalose) and hydroxyethyl starch (HES) mass ratios. Protein degradation was assessed as a function of time of storage of the dried formulations at 40, 50 and 60 °C. Lyophilized and stored samples were rehydrated, and protein degradation was quantified by measuring loss of monomeric protein with size exclusion chromatography and by determining chemical degradation in the soluble fraction with reverse-phase chromatography. The secondary structure of the protein in the lyophilized formulations was studied with infrared spectroscopy. The magnitudes of degradation were compared the key physical properties of the formulations including retention of protein native secondary structure, glass transition temperature (Tg), inverse mean square displacements ?1 for hydrogen atoms (fast ? relaxation), and the relaxation time ??, which correlates with relaxation due to fast Johari-Goldstein motions in the glass[1]. In addition, specific surface areas of the lyophilized formulations were determined by Brunauer-Emmet-Teller analysis of krypton adsorption isotherms and used to estimate the fraction of the KGF-2 molecules residing at the solid-air interface. KGF-2 degradation rates were highest in formulations wherein the protein’s structure was most perturbed, and wherein ? relaxations were fastest, but the dominant factor governing KGF-2 degradation in freeze-dried formulations was the fraction of the protein found at the glass solid-air interface. PMID:24859390

  13. Aberrant signalling and transcription factor activation as an explanation for the defective growth control and differentiation of keratinocytes in psoriasis: a hypothesis.

    PubMed

    McKenzie, R C; Sabin, E

    2003-08-01

    Psoriasis is a chronic inflammatory skin disease characterized by the accumulation of red, scaly plaques on the skin. The plaques result from hyperproliferation and incomplete differentiation of keratinocytes (KC) in a process that seems to be driven, in part by skin-infiltrating leucocytes. We believe that the KC have inherent defects in intracellular signalling which could be usefully targeted to allow the development of more effective therapies. We suggest that there are defects in the regulation of the transcription factors: signal transducer and activator of transcription (STAT-1alpha), interferon regulated factor-1 (IRF-1) and NFkappaB which lead to loss of growth and differentiation control when the cells are subjected to physico-chemical and immunological stress. We also highlight recent studies that suggest that peroxisome proliferator-activated receptors, the notch receptor and defects in calcium and other ion transporting proteins may contribute to impairment in the ability of psoriatic KC to differentiate. The role of these systems in the development of the psoriatic phenotype and tests of these hypotheses are proposed. PMID:12930288

  14. Storage stability of keratinocyte growth factor-2 in lyophilized formulations: effects of formulation physical properties and protein fraction at the solid-air interface.

    PubMed

    Devineni, Dilip; Gonschorek, Christoph; Cicerone, Marcus T; Xu, Yemin; Carpenter, John F; Randolph, Theodore W

    2014-10-01

    Lyophilized formulations of keratinocyte growth factor-2 (KGF-2) were prepared with a range of disaccharide (sucrose or trehalose) and hydroxyethyl starch (HES) mass ratios. Protein degradation was assessed as a function of time of storage of the dried formulations at 40, 50 and 60°C. Lyophilized and stored samples were rehydrated, and protein degradation was quantified by measuring loss of monomeric protein with size exclusion chromatography and by determining chemical degradation in the soluble fraction with reverse-phase chromatography. The secondary structure of the protein in the lyophilized formulations was studied with infrared spectroscopy. The magnitudes of degradation were compared the key physical properties of the formulations including retention of protein native secondary structure, glass transition temperature (Tg), inverse mean square displacements ?u(2)?(-1) for hydrogen atoms (fast ? relaxation), and the relaxation time ?(?), which correlates with relaxation due to fast Johari-Goldstein motions in the glass (Xu et al., 2013) [1]. In addition, specific surface areas of the lyophilized formulations were determined by Brunauer-Emmet-Teller analysis of krypton adsorption isotherms and used to estimate the fraction of the KGF-2 molecules residing at the solid-air interface. KGF-2 degradation rates were highest in formulations wherein the protein's structure was most perturbed, and wherein ? relaxations were fastest, but the dominant factor governing KGF-2 degradation in freeze-dried formulations was the fraction of the protein found at the glass solid-air interface. PMID:24859390

  15. 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. PMID:26160987

  16. AMPK regulation of the growth of cultured human keratinocytes

    SciTech Connect

    Saha, Asish K. . E-mail: aksaha@bu.edu; Persons, Kelly; Safer, Joshua D.; Luo Zhijun; Holick, Michael F.; Ruderman, Neil B.

    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.

  17. Effects of the neuropeptides substance P, calcitonin gene-related peptide, vasoactive intestinal polypeptide and galanin on the production of nerve growth factor and inflammatory cytokines in cultured human keratinocytes.

    PubMed

    Dallos, Attila; Kiss, Mária; Polyánka, Hilda; Dobozy, Attila; Kemény, Lajos; Husz, Sándor

    2006-08-01

    Neuropeptides released from the cutaneous sensory nerve endings have neurotransmitter and immunoregulatory roles; they exert mitogenic actions and can influence the functions of different cell types in the skin. The aims of this study were a systematic investigation of the effects of the neuropeptides substance P (SP), calcitonin gene-related peptide (CGRP), vasoactive intestinal polypeptide (VIP) and galanin (GAL) on the inflammatory cytokine production (IL-1alpha, IL-8 and TNF-alpha) of the keratinocytes, and a study of their role in the production and secretion of nerve growth factor (NGF) and its precursor molecule (proNGF). Cultures of normal human keratinocytes were treated with 10(-8)M SP, CGRP, VIP or GAL for 30 min. After different time intervals, cells were harvested for total RNA isolation; in addition, cell lysates and supernatants were collected. The effects of the neuropeptides on the mRNA expressions of the different cytokines and NGF were investigated by Q-RT-PCR and the protein levels were studied by means of ELISA assays and Western blotting. Each of the four neuropeptides induced increases in the expressions of IL-1alpha, IL-8 and TNF-alpha mRNA. Increases appeared in the amount of the IL-1alpha protein in the supernatants of neuropeptide-treated cells, and the IL-8 secretion was mildly elevated, while secretion of TNF-alpha remained undetectable. The four neuropeptides increased the NGF mRNA expression to different extents. In the cell lysates of the keratinocytes, only proNGF could be detected, its concentration in the neuropeptide-treated cells being approximately twice that in the time-matched controls. Both control cultures and neuropeptide-treated cultures were found to secrete proNGF and mature NGF, but neuropeptide-treated cell cultures produced markedly higher (3-7-fold) amounts of NGF-like immunoreactive materials. The results demonstrated that neuropeptides released from cutaneous nerves after an injurious stimulus are able to induce an upregulation of IL-1alpha and IL-8 production; they are additionally able to influence the expressions of proNGF/NGF and their secretion from the keratinocytes. These findings may contribute toward an understanding of the neural influence on skin health and disease. PMID:16904178

  18. Role of keratinocyte-derived factors involved in regulating the proliferation and differentiation of mammalian epidermal melanocytes.

    PubMed

    Hirobe, Tomohisa

    2005-02-01

    Melanocytes characterized by the activities of tyrosinase, tyrosinase-related protein (TRP)-1 and TRP-2 as well as by melanosomes and dendrites are located mainly in the epidermis, dermis and hair bulb of the mammalian skin. Melanocytes differentiate from melanoblasts, undifferentiated precursors, derived from embryonic neural crest cells. Because hair bulb melanocytes are derived from epidermal melanoblasts and melanocytes, the mechanism of the regulation of the proliferation and differentiation of epidermal melanocytes should be clarified. The regulation by the tissue environment, especially by keratinocytes is indispensable in addition to the regulation by genetic factors in melanocytes. Recent advances in the techniques of tissue culture and biochemistry have enabled us to clarify factors derived from keratinocytes. Alpha-melanocyte-stimulating hormone, adrenocorticotrophic hormone, basic fibroblast growth factor, nerve growth factor, endothelins, granulocyte-macrophage colony-stimulating factor, steel factor, leukemia inhibitory factor and hepatocyte growth factor have been suggested to be the keratinocyte-derived factors and to regulate the proliferation and/or differentiation of mammalian epidermal melanocytes. Numerous factors may be produced in and released from keratinocytes and be involved in regulating the proliferation and differentiation of mammalian epidermal melanocytes through receptor-mediated signaling pathways. PMID:15649147

  19. Human hair follicle dermal sheath and papilla cells support keratinocyte growth in monolayer coculture.

    PubMed

    Hill, Rebecca P; Gardner, Aaron; Crawford, Heather C; Richer, Rachel; Dodds, Anna; Owens, William A; Lawrence, Clifford; Rao, Sam; Kara, Bo; James, S Elizabeth; Jahoda, Colin A

    2013-03-01

    Traditional skin grafting techniques are effective but limited methods of skin replacement. Autologous transplantation of rapidly cultured keratinocytes is successful for epidermal regeneration, but the current gold-standard technique requires mouse fibroblast feeders and serum-rich media, with serum-free systems and dermal fibroblast (DF) feeders performing relatively poorly. Here, we investigated the capacity of human hair follicle dermal cells to act as alternative supports for keratinocyte growth. Dermal papilla (DP) dermal sheath (DS), DF and 3T3 cells were used as inactivated feeder cells for human keratinocyte coculture. Under conditions favouring dermal cells, proliferation of keratinocytes in the presence of either DS or DP cells was significantly enhanced compared with DF cells, at levels comparable to keratinocytes cultured under gold-standard conditions. Secreted protein acidic and rich in cysteine (SPARC) expression increased DS and DP cells relative to DFs; however, further experiments did not demonstrate a role in keratinocyte support. PMID:23489431

  20. Expression and growth inhibitory effect of decapentaplegic Vg-related protein 6: evidence for a regulatory role in keratinocyte differentiation.

    PubMed

    Drozdoff, V; Wall, N A; Pledger, W J

    1994-06-01

    Decapentaplegic Vg-related protein 6 (DVR-6 or bone morphogenetic protein BMP-6) is a member of the DVR subgroup of the transforming growth factor beta superfamily, a large group of multifunctional signaling polypeptides that are expressed as secreted disulfide-bonded dimers proteolytically cleaved from larger precursors. The predominant expression of DVR-6 in the differentiating postmitotic layers of stratified squamous epithelia strongly suggests a role for DVR-6 in regulation of epithelial differentiation. In primary mouse keratinocytes induced to differentiate by suspension culture in methylcellulose, new expression of DVR-6 mRNA and protein was detected within 8 h among a majority of the suspended cells, which preceded the induction of expression of the suprabasal keratins K1 and K10. To test the hypothesis that DVR-6 is a keratinocyte growth regulatory factor, a retroviral expression vector expressing human DVR-6 was used to infect attached cultures of undifferentiated basal cells. Expression of DVR-6 in primary mouse keratinocytes before differentiation resulted in the secretion of prepro and processed (pro region) forms in the conditioned medium and a dramatic inhibition of cell growth. These findings suggest that inhibition of cell growth by DVR-6 may be a primary step in keratinocyte differentiation. PMID:7515504

  1. 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.; Williams, A.C.; Howarth, J.L.; Glover, C.P.; Uney, J.B.; Hague, A.

    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.

  2. Ratite oils promote keratinocyte cell growth and inhibit leukocyte activation.

    PubMed

    Bennett, Darin C; Leung, Gigi; Wang, Eddy; Ma, Sam; Lo, Blanche K K; McElwee, Kevin J; Cheng, Kimberly M

    2015-09-01

    Traditionally, native Australian aborigines have used emu oil for the treatment of inflammation and to accelerate wound healing. Studies on mice suggest that topically applied emu oil may have anti-inflammatory properties and may promote wound healing. We investigated the effects of ratite oils (6 emu, 3 ostrich, 1 rhea) on immortalized human keratinocytes (HaCaT cells) in vitro by culturing the cells in media with oil concentrations of 0%, 0.5%, and 1.0%. Peking duck, tea tree, and olive oils were used as comparative controls. The same oils at 0.5% concentration were evaluated for their influence on peripheral blood mononuclear cell (PBMC) survival over 48 hr and their ability to inhibit IFN? production in PBMCs activated by phytohemagglutinin (PHA) in ELISpot assays. Compared to no oil control, significantly shorter population doubling time durations were observed for HaCaT cells cultured in emu oil (1.51×faster), ostrich oil (1.46×faster), and rhea oil (1.64×faster). Tea tree oil demonstrated significant antiproliferative activity and olive oil significantly prolonged (1.35×slower) cell population doubling time. In contrast, almost all oils, particularly tea tree oil, significantly reduced PBMC viability. Different oils had different levels of inhibitory effect on IFN? production with individual emu, ostrich, rhea, and duck oil samples conferring full inhibition. This preliminary investigation suggests that emu oil might promote wound healing by accelerating the growth rate of keratinocytes. Combined with anti-inflammatory properties, ratite oil may serve as a useful component in bandages and ointments for the treatment of wounds and inflammatory skin conditions. PMID:26217022

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

    SciTech Connect

    Shi, Ge; Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, 301-747; Department of Dermatology, The First Affiliated Hospital, Guangxi Traditional Chinese Medical University, Guangxi, Nanning, 530023 ; Sohn, Kyung-Cheol; Choi, Tae-Young; Choi, Dae-Kyoung; Lee, Sang-Sin; Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, 301-747 ; Ou, Bai-sheng; Kim, Sooil; Lee, Young Ho; Yoon, Tae-Jin; Institute of Health Sciences, School of Medicine, Gyeongsang National University, Jinju, 660-702 ; Kim, Seong-Jin; Lee, Young; Seo, Young-Joon; Lee, Jeung-Hoon; Research Institute for Medical Sciences, School of Medicine, Chungnam National University, Daejeon, 301-747 ; Kim, Chang Deok

    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.

  4. Induction of transcription factor AP-2 by inflammatory cytokines in human keratinocytes.

    PubMed

    Oyama, N; Iwatsuki, K; Homma, Y; Kaneko, F

    1999-10-01

    Activator protein-2 is an important transcription factor for the activation of a number of genes. Here we report the induction of activator protein-2 in response to inflammatory cytokines such as interleukin-6 in keratinocytes. Immunoblotting and semiquantitative reverse transcriptase-polymerase chain reaction assays using normal human keratinocytes revealed that interleukin-6 caused a time- and concentration-dependent induction of activator protein-2 mRNA and protein. The increase of activator protein-2 mRNA was detected at 30 min after stimulation and that of activator protein-2 protein was at 2 h. Their levels were lower than the control levels at 24 h. The interleukin-6-dependent induction of activator protein-2 mRNA was completely blocked by adding actinomycin D, whereas it was approximately 50% affected by cycloheximide. Co-incubation with neutralizing antibodies against various inflammatory cytokines resulted in inhibition of the interleukin-6-dependent activator protein-2 induction at varying degrees, indicating an involvement of various cytokines in the activator protein-2 induction. The activator protein-2 induction was observed in keratinocytes derived from lesional skins with psoriasis or squamous cell carcinoma, and the high levels of activator protein-2 were histochemically detected in these lesions. Furthermore, a gel mobility shift assay using the nuclear extracts from interleukin-6-treated cells showed that interleukin-6 induced the functional activator protein-2 protein for the gene activation. These findings suggest a possible regulation mechanism of activator protein-2 through a complex cytokine system, which is conceivably the initial reaction leading to skin inflammation, and resultant keratinocyte growth and carcinogenesis. PMID:10504447

  5. A Keratinocyte Hypermotility/Growth-Arrest Response Involving Laminin 5 and p16INK4A Activated in Wound Healing and Senescence

    PubMed Central

    Natarajan, Easwar; Omobono, John D.; Guo, Zongyou; Hopkinson, Susan; Lazar, Alexander J.F.; Brenn, Thomas; Jones, Jonathan C.; Rheinwald, James G.

    2006-01-01

    Keratinocytes become migratory to heal wounds, during early neoplastic invasion, and when undergoing telomere-unrelated senescence in culture. All three settings are associated with expression of the cell cycle inhibitor p16INK4A (p16) and of the basement membrane protein laminin 5 (LN5). We have investigated cause-and-effect relationships among laminin 5, p16, hypermotility, and growth arrest. Plating primary human keratinocytes on the ?2 precursor form of laminin 5 (LN5?) immediately induced directional hypermotility at ?125 ?m/hour, followed by p16 expression and growth arrest. Cells deficient in p16 and either p14ARF or p53 became hypermotile in response to LN5? but did not arrest growth. Plating on LN5? triggered smad nuclear translocation, and all LN5? effects were blocked by a transforming growth factor (TGF) ? receptor I (TGF?RI) kinase inhibitor. In contrast, plating cells on collagen I triggered a TGF?RI kinase-independent hypermotility unaccompanied by smad translocation or growth arrest. Plating on control surfaces with TGF? induced hypermotility after a 1-day lag time and growth arrest by a p16-independent mechanism. Keratinocytes serially cultured with TGF?RI kinase inhibitor exhibited an extended lifespan, and immortalization was facilitated following transduction to express the catalytic subunit of telomerase (TERT). These results reveal fundamental features of a keratinocyte hypermotility/growth-arrest response that is activated in wound healing, tumor suppression, and during serial cul-ture. PMID:16723698

  6. Motogenic substrata and chemokinetic growth factors for human skin cells

    PubMed Central

    Sutherland, Jennifer; Denyer, Morgan; Britland, Stephen

    2005-01-01

    Extracellular matrix remodelling and accurate spatio-temporal coordination of growth factor expression are two factors that are believed to regulate mitoses and cell migration in developing and regenerating tissues. The present quantitative videomicroscopical study examined the influence of some of the principal components of extracellular matrix and several growth factors that are known to be expressed in dermal wounds on three important facets of human skin cell behaviour in culture. Keratinocytes, melanocytes and dermal fibroblasts (and myofibroblast controls) exhibited varying degrees of substrate adhesion, division and migration depending on the composition of the culture substrate. Substrates that are recognized components of transitional matrices generally accentuated cell adhesion and proliferation, and were motogenic, when compared with serum-treated control surfaces, whereas components of more stable structures such as basement membrane had less influence. Platelet-derived growth factor (PDGF), epidermal growth factor (EGF) and ? fibroblastic growth factor (?FGF) all promoted cell proliferation and were chemokinetic to dermal fibroblasts, but not keratinocyte growth factor (KGF) or transforming growth factor ? (TGF?). PDGF, EGF and KGF, but not TGF? or ?FGF, all enhanced proliferation of dermal keratinocytes. The same growth factors, and in addition KGF, all stimulated motility in keratinocytes, but TGF? and ?FGF again had no effect. Developing a better understanding of the interdependency of factors that control crucial cell behaviour may assist those who are interested in the regulation of histogenesis and also inform the development of rational therapeutic strategies for the management of chronic and poorly healed wounds. PMID:16011545

  7. Epidermal nerve fibers modulate keratinocyte growth via neuropeptide signaling in an innervated skin model.

    PubMed

    Roggenkamp, Dennis; Köpnick, Sarah; Stäb, Franz; Wenck, Horst; Schmelz, Martin; Neufang, Gitta

    2013-06-01

    Atopic eczema is a chronic inflammatory skin disease characterized by cutaneous nerve fiber sprouting and epidermal hyperplasia, pointing to an involvement of the peripheral nervous system in cutaneous homeostasis. However, the interaction of sensory neurons and skin cells is poorly understood. Using an innervated skin model, we investigated the influence of sensory neurons on epidermal morphogenesis. Neurons induced the proliferation of keratinocytes, resulting in an increase in the epidermal thickness. Inhibition of calcitonin gene-related peptide (CGRP), but not substance P (SP) signaling, reversed this effect. Human CGRP enhanced keratinocyte proliferation and epidermal thickness in skin models, demonstrating a key role of CGRP in modulating epidermal morphogenesis, whereas SP had only a moderate effect. Innervated skin models composed of atopic skin cells showed increased neurite outgrowth, accompanied by elevated CGRP release. As atopic keratinocytes were sensitized to CGRP owing to higher expression levels of the CGRP receptor components, receptor activity-modifying protein 1 (RAMP1) and receptor component protein (RCP), atopic innervated skin models displayed a thicker epidermis than did healthy controls. We conclude that neural CGRP controls local keratinocyte growth. Our results show that the crosstalk of the cutaneous peripheral nervous system and skin cells significantly influences epidermal morphogenesis and homeostasis in healthy and atopic skin. PMID:23283070

  8. Lithium Regulates Keratinocyte Proliferation Via Glycogen Synthase Kinase 3 and NFAT2 (Nuclear Factor of Activated T Cells 2)

    PubMed Central

    Hampton, Philip J; Jans, Ralph; Flockhart, Ross J; Parker, Graeme; Reynolds, Nick J

    2012-01-01

    Certain environmental factors including drugs exacerbate or precipitate psoriasis. Lithium is the commonest cause of drug-induced psoriasis but underlying mechanisms are currently unknown. Lithium inhibits glycogen synthase kinase 3 (GSK-3). As lithium does not exacerbate other T-cell-mediated chronic inflammatory diseases, we investigated whether lithium may be acting directly on epidermal keratinocytes by inhibiting GSK-3. We report that lithium-induced keratinocyte proliferation at therapeutically relevant doses (1–2 mM) and increased the proportion of cells in S phase of the cell cycle. Inhibition of GSK-3 in keratinocytes by retroviral transduction of GSK-binding protein (an endogenous inhibitory protein) or through a highly selective pharmacological inhibitor also resulted in increased keratinocyte proliferation. Nuclear factor of activated T cells (NFAT) is an important substrate for GSK-3 and for cyclosporin, an effective treatment for psoriasis that inhibits NFAT activation in keratinocytes as well as in lymphocytes. Both lithium and genetic/pharmacological inhibition of GSK-3 resulted in increased nuclear localization of NFAT2 (NFATc1) and increased NFAT transcriptional activation. Finally, retroviral transduction of NFAT2 increased keratinocyte proliferation whereas siRNA-mediated knockdown of NFAT2 reduced keratinocyte proliferation and decreased epidermal thickness in an organotypic skin equivalent model. Taken together, these data identify GSK-3 and NFAT2 as key regulators of keratinocyte proliferation and as potential molecular targets relevant to lithium-provoked psoriasis. J. Cell. Physiol. 227: 1529–1537, 2012. © 2011 Wiley Periodicals, Inc. PMID:21678407

  9. CCN1, a Pro-Inflammatory Factor, Aggravates Psoriasis Skin Lesions by Promoting Keratinocyte Activation.

    PubMed

    Sun, Yue; Zhang, Jie; Zhou, Zhou; Wu, Pinru; Huo, Rongfen; Wang, Beiqing; Shen, Zhengyu; Li, Huidan; Zhai, Tianhang; Shen, Baihua; Chen, Xiangdong; Li, Ningli

    2015-11-01

    Psoriasis is a common chronic skin disease characterized by epidermal hyperplasia and inflammation. The pathogenesis of psoriasis is multifactorial and is not fully understood. Here we demonstrate that CCN1 (also called Cyr61, which is short for cysteine-rich 61), an extracellular matrix protein that is also considered a pro-inflammatory factor, is highly expressed in the lesional skin of psoriasis patients, as well as in that of imiquimod (IMQ)- and IL-23-treated psoriasis-like mice. Then we show that blocking CCN1 function in vivo attenuates epidermal hyperplasia and inflammation in psoriasis-like mice. Further, in primary cultured normal human keratinocytes and HaCaT (human keratinocyte cell line) cells, CCN1 promotes keratinocyte activation, including the proliferation and expression of immune-related molecules. Finally, we observe that integrin ?6?1 is the receptor of CCN1 in keratinocytes, and CCN1 stimulation activates the downstream phosphoinositide-3 kinase/Akt/NF-?B signaling pathway. Taken together, our findings reveal that CCN1 has a critical role in psoriasis pathogenesis. Moreover, as CCN1 is a secreted extracellular matrix (ECM) protein, our study also provides evidence that ECM, which is involved in psoriatic pathogenesis, could be a potent target for psoriasis treatment. PMID:26099024

  10. Expression of the human papillomavirus type 16 E7 oncoprotein induces an autophagy-related process and sensitizes normal human keratinocytes to cell death in response to growth factor deprivation

    SciTech Connect

    Zhou Xiaobo; Muenger, Karl

    2009-03-01

    Expression of oncogenes, such as the human papillomavirus type 16 (HPV16) E7 oncoprotein, promotes aberrant cell proliferation. In the absence of concurrent mitogenic stimuli, this triggers a cell-intrinsic defense mechanism, the 'trophic sentinel response', which eliminates such aberrant cells. The molecular pathways that elicit this response, however, remain obscure. We set up an experimental system to investigate the trophic sentinel pathway triggered by HPV16 E7 expression in normal human keratinocytes, the natural host cells of HPVs. Keratinocytes expressing HPV16 E7 cultured in E-medium undergo cell death and show increased sub-G1 DNA content when grown to confluence or under conditions of serum deprivation. Moreover, HPV16 E7 expressing human keratinocytes express higher levels of the autophagy marker, LC3-II, which can be abrogated by 3-methyladenine, an autophagy inhibitor. These findings indicate that even under normal culture conditions, HPV16 E7 expression triggers metabolic stress that may result in autophagy, a pathway implicated in carcinogenesis.

  11. Mechanisms of growth inhibition in keratinocytes by mercurio-substituted 4',5'-dihydropsoralens.

    PubMed

    Martey, Christine A; Vetrano, Anna M; Whittemore, Marilyn S; Mariano, Thomas M; Gentile, Shannon L; Heck, Diane E; Laskin, Debra L; Heindel, Ned D; Laskin, Jeffrey D

    2002-06-01

    Psoralens, together with ultraviolet light A (PUVA), are used in the treatment of epidermal proliferative disorders. Although these compounds can enter cells and photo cross-link DNA, lipids and proteins, including a specific membrane receptor, are also potential targets for the psoralens. To better elucidate the site of action of the psoralens, we have synthesized a family of 5'-mercurio-substituted derivatives of 4',5'-dihydropsoralen. These compounds are identified by their heavy metal content and can be used as a model to deliver thiol reactive psoralen derivatives into keratinocytes. The 5'-mercuriopsoralen derivatives were found to be effective inhibitors of keratinocyte growth without photoactivation. The most active compound, 4,8-dimethyl-5'-iodomercuriomethyl-4',5'-dihydropsoralen (IC50=10 microM), was also a potent photosensitizer (IC50=0.3 microM). Depletion of keratinocyte GSH with buthionine sulfoximine markedly increased their sensitivity to this analog, both with and without UVA light. In contrast, N-acetyl-L-cysteine partially protected the cells from growth inhibition, indicating that a sulfhydryl-sensitive site is growth limiting and that this target can be photoactivated. Iodomercurio-4',5'-dihydropsoralen was found to form adducts with GSH and cysteine, which were not active without UVA light. Thus, these adducts may also contribute to the photosensitization reactions of the parent compound. Using plasmid DNA unwinding assays, iodomercurio-4',5'-dihydropsoralen was also found to modify DNA, an activity that increased following UVA light treatment. This suggests that DNA damage may contribute to the actions of these psoralens. Taken together, our data demonstrate that there are multiple sites of action for mercuriopsoralens. These compounds may prove useful for understanding the mechanisms of psoralen-induced growth inhibition in the skin. PMID:12093477

  12. A Method for the Immortalization of Newborn Mouse Skin Keratinocytes

    PubMed Central

    Hammiller, Brianna O.; El-Abaseri, Taghrid Bahig; Dlugosz, Andrzej A.; Hansen, Laura A.

    2015-01-01

    Isolation and culture of mouse primary epidermal keratinocytes is a common technique that allows for easy genetic and environmental manipulation. However, due to their limited lifespan in culture, experiments utilizing primary keratinocytes require large numbers of animals, and are time consuming and expensive. To avoid these issues, we developed a method for the immortalization of primary mouse epidermal keratinocytes. Upon isolation of newborn epidermal keratinocytes according to established methods, the cells were cultured long-term in keratinocyte growth factor-containing medium. The cells senesced within a few weeks and eventually, small, slowly growing colonies emerged. After they regained confluency, the cells were passaged and slowly refilled the dish. With several rounds of subculture, the cells adapted to culture conditions, were easily subcultured, maintained normal morphology, and were apparently immortal. The immortalized cells retained the ability to differentiate with increased calcium concentrations, and were maintained to high passage numbers while maintaining a relatively stable karyotype. Analysis of multiple immortalized cell lines as well as primary keratinocyte cultures revealed increased numbers of chromosomes, especially in the primary keratinocytes, and chromosomal aberrations in most of the immortalized cultures and in the primary keratinocytes. Orthotopic grafting of immortalized keratinocytes together with fibroblasts onto nude mouse hosts produced skin while v-rasHa infection of the immortalized keratinocytes prior to grafting produced squamous cell carcinoma. In summary, this method of cell line generation allows for decreased use of animals, reduces the expense and time involved in research, and provides a useful model for cutaneous keratinocyte experimentation. PMID:26284198

  13. 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. )

    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.

  14. 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

  15. The Tumor Necrosis Factor Superfamily Molecule LIGHT Promotes Keratinocyte Activity and Skin Fibrosis.

    PubMed

    Herro, Rana; Antunes, Ricardo Da S; Aguilera, Amelia R; Tamada, Koji; Croft, Michael

    2015-08-01

    Several inflammatory diseases including scleroderma and atopic dermatitis display dermal thickening, epidermal hypertrophy, or excessive accumulation of collagen. Factors that might promote these features are of interest for clinical therapy. We previously reported that LIGHT, a TNF superfamily molecule, mediated collagen deposition in the lungs in response to allergen. We therefore tested whether LIGHT might similarly promote collagen accumulation and features of skin fibrosis. Strikingly, injection of recombinant soluble LIGHT into naive mice, either subcutaneously or systemically, promoted collagen deposition in the skin and dermal and epidermal thickening. This replicated the activity of bleomycin, an antibiotic that has been previously used in models of scleroderma in mice. Moreover skin fibrosis induced by bleomycin was dependent on endogenous LIGHT activity. The action of LIGHT in vivo was mediated via both of its receptors, HVEM and LT?R, and was dependent on the innate cytokine TSLP and TGF-?. Furthermore, we found that HVEM and LT?R were expressed on human epidermal keratinocytes and that LIGHT could directly promote TSLP expression in these cells. We reveal an unappreciated activity of LIGHT on keratinocytes and suggest that LIGHT may be an important mediator of skin inflammation and fibrosis in diseases such as scleroderma or atopic dermatitis. PMID:25789702

  16. FGF growth factor analogs

    DOEpatents

    Zamora, Paul O. (Gaithersburg, MD); Pena, Louis A. (Poquott, NY); Lin, Xinhua (Plainview, NY); Takahashi, Kazuyuki (Germantown, MD)

    2012-07-24

    The present invention provides a fibroblast growth factor heparin-binding analog of the formula: ##STR00001## where R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, X, Y and Z are as defined, pharmaceutical compositions, coating compositions and medical devices including the fibroblast growth factor heparin-binding analog of the foregoing formula, and methods and uses thereof.

  17. Peptide growth factors, part A

    SciTech Connect

    Barnes, D.; Sirbasku, D.A.

    1987-01-01

    This book contains information on the following topics: Epidermal Growth Factor;Transforming Growth Factors;Bone and Cartilage Growth Factors;Somatomedin/Insulin-Like Growth Factors;Techniques for the Study of Growth Factor Activity;Assays, Phosphorylation, and Surface Membrane Effects.

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

    PubMed Central

    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

  19. Growth factors for nanobacteria

    NASA Astrophysics Data System (ADS)

    Ciftcioglu, Neva; Kajander, E. Olavi

    1999-12-01

    Nanobacteria are novel microorganisms recently isolated from fetal bovine serum and blood of cows and humans. These coccoid, gram negative bacteria in alpha-2 subgroup of Proteobacteria grow slowly under mammalian cell culture conditions but not in common media for microbes. Now we have found two different kinds of culture supplement preparations that improve their growth and make them culturable in the classical sense. These are supernatant fractions of conditioned media obtained from 1 - 3 months old nanobacteria cultures and from about a 2 weeks old Bacillus species culture. Both improved multiplication and particle yields and the latter increased their resistance to gentamicin. Nanobacteria cultured with any of the methods shared similar immunological property, structure and protein pattern. The growth supporting factors were heat-stabile and nondialyzable, and dialysis improved the growth promoting action. Nanobacteria formed stony colonies in a bacteriological medium supplemented with the growth factors. This is an implication that nanobacterial growth is influenced by pre-existing bacterial flora.

  20. New microbial growth factor

    NASA Technical Reports Server (NTRS)

    Bok, S. H.; Casida, L. E., Jr.

    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 previously unknown 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 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.

  1. 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

  2. NF-?B Protects Human Papillomavirus Type 38 E6/E7-Immortalized Human Keratinocytes against Tumor Necrosis Factor Alpha and UV-Mediated Apoptosis?

    PubMed Central

    Hussain, Ishraq; Fathallah, Ikbal; Accardi, Rosita; Yue, Jiping; Saidj, Djamel; Shukla, Ruchi; Hasan, Uzma; Gheit, Tarik; Niu, Yamei; Tommasino, Massimo; Sylla, Bakary S.

    2011-01-01

    Constitutive activation of NF-?B signaling is a key event in virus- and non-virus-induced carcinogenesis. We have previously reported that cutaneous human papillomavirus type 38 (HPV38) displays transforming properties in in vitro and in vivo experimental models. However, the involvement of NF-?B signaling in HPV38-induced cell growth transformation remains to be determined. In this study, we showed that HPV38 E6 and E7 activate NF-?B and that inhibition of the pathway with the I?B? superrepressor sensitizes HPV38E6E7-immortalized human keratinocytes to tumor necrosis factor alpha (TNF-?)- and UVB radiation-mediated apoptosis. Accordingly, inhibition of NF-?B signaling resulted in the downregulation of NF-?B-regulated antiapoptotic genes, including cIAP1, cIAP2, and xIAP genes. These findings demonstrate a critical role of NF-?B activity in the survival of HPV38E6E7-immortalized human keratinocytes exposed to cytokine or UV radiation. Our data provide additional evidence for cooperation between beta HPV infection and UV irradiation in skin carcinogenesis. PMID:21715489

  3. Hematopoietic growth factors.

    PubMed

    Bociek, R G; Armitage, J O

    1996-01-01

    Over the past ten years, the availability of pharmacologic quantities of hematopoietic growth factors has opened many avenues of study in basic science and clinical investigation. Numerous studies performed to date have demonstrated significant benefits from the use of these cytokines. The side effect profiles, particularly for "later acting" growth factors, indicate that they are generally well tolerated by most patients. The table summarizes the potential indications for hematopoietic growth factor use as discussed in this article, as justified by current evidence of benefit, harm, and cost effectiveness resulting from their use in various clinical settings. It has been clearly demonstrated in standard-dose chemotherapy regimens that these agents shorten the duration of myelosuppression, reduce the incidence of significant infection, can shorten hospital stay, and reduce antibiotic use for most patients, although the cost/benefit ratio for growth factors such as G-CSF makes this a cost-effective approach only for regimens with a high (40 percent or more) incidence of febrile neutropenia. Limited indirect evidence supports the use of growth factors in patients with a prior episode of fever and neutropenia. The suppressive approach to growth factor use could potentially benefit patients with documented infection or clinical deterioration, but it has not otherwise been shown to be a particularly effective or cost-effective approach. Administration of hematopoietic growth factors has been instrumental in facilitating both autologous and allogeneic peripheral progenitor cell mobilization and techniques such as ex vivo expansion. There is an increasing body of data supporting the use of high-dose chemotherapy regimens with progenitor cell rescue for a number of malignancies and limited data supporting the benefits of maintaining dose-intensity for certain malignancies in standard-dose settings. Although of continuing concern, clinically significant evidence of disease stimulation and recurrence has not been unequivocally demonstrated in studies to date. A comprehensive set of evidence-based guidelines has recently been published by the American Society of Clinical Oncology. As often is the case, current studies have perhaps generated more questions than answers. Future investigation will undoubtedly focus on use of hematopoietic growth factors in conjunction with other techniques, such as outpatient-based treatment of febrile neutropenia, CD34-positive stem cell selection in autologous transplantation, selective manipulation of T-cell subsets (to decrease the incidence of severe graft-versus-host disease) in allogeneic transplantation, and high-dose therapy with stem cell transplantation. PMID:8646546

  4. Receptor-interacting Protein Kinase 4 and Interferon Regulatory Factor 6 Function as a Signaling Axis to Regulate Keratinocyte Differentiation*

    PubMed Central

    Kwa, Mei Qi; Huynh, Jennifer; Aw, Jiamin; Zhang, Lianyi; Nguyen, Thao; Reynolds, Eric C.; Sweet, Matthew J.; Hamilton, John A.; Scholz, Glen M.

    2014-01-01

    Receptor-interacting protein kinase 4 (RIPK4) and interferon regulatory factor 6 (IRF6) are critical regulators of keratinocyte differentiation, and their mutation causes the related developmental epidermal disorders Bartsocas-Papas syndrome and popliteal pterygium syndrome, respectively. However, the signaling pathways in which RIPK4 and IRF6 operate to regulate keratinocyte differentiation are poorly defined. Here we identify and mechanistically define a direct functional relationship between RIPK4 and IRF6. Gene promoter reporter and in vitro kinase assays, coimmunoprecipitation experiments, and confocal microscopy demonstrated that RIPK4 directly regulates IRF6 trans-activator activity and nuclear translocation. Gene knockdown and overexpression studies indicated that the RIPK4-IRF6 signaling axis controls the expression of key transcriptional regulators of keratinocyte differentiation, including Grainyhead-like 3 and OVO-like 1. Additionally, we demonstrate that the p.Ile121Asn missense mutation in RIPK4, which has been identified recently in Bartsocas-Papas syndrome, inhibits its kinase activity, thereby preventing RIPK4-mediated IRF6 activation and nuclear translocation. We show, through mutagenesis-based experiments, that Ser-413 and Ser-424 in IRF6 are important for its activation by RIPK4. RIPK4 is also important for the regulation of IRF6 expression by the protein kinase C pathway. Therefore, our findings not only provide important mechanistic insights into the regulation of keratinocyte differentiation by RIPK4 and IRF6, but they also suggest one mechanism by which mutations in RIPK4 may cause epidermal disorders (e.g. Bartsocas-Papas syndrome), namely by the impaired activation of IRF6 by RIPK4. PMID:25246526

  5. Loss of nuclear receptor RXR? in epidermal keratinocytes promotes the formation of Cdk4-activated invasive melanomas.

    PubMed

    Hyter, Stephen; Bajaj, Gaurav; Liang, Xiaobo; Barbacid, Mariano; Ganguli-Indra, Gitali; Indra, Arup Kumar

    2010-10-01

    Keratinocytes contribute to melanocyte transformation by affecting their microenvironment, in part through the secretion of paracrine factors. Here we report a loss of expression of nuclear receptor RXR? in epidermal keratinocytes during human melanoma progression. In the absence of keratinocytic RXR?, in combination with mutant Cdk4, cutaneous melanoma was generated that metastasized to lymph nodes in a bigenic mouse model. Expression of several keratinocyte-derived mitogenic growth factors (Et-1, Hgf, Scf, ?-MSH and Fgf?2?) was elevated in skin of bigenic mice, whereas Fas, E-cadherin and Pten, implicated in apoptosis, cellular invasion and melanomagenesis, respectively, were downregulated within the microdissected melanocytic tumors. We demonstrated that RXR? is recruited on the proximal promoter of both Et-1 and Hgf, possibly directly regulating their transcription in keratinocytes. These studies demonstrate the contribution of keratinocytic paracrine signaling during the cellular transformation and malignant conversion of melanocytes. PMID:20629968

  6. Factors affecting ultraviolet-A photon emission from ?-irradiated human keratinocyte cells

    NASA Astrophysics Data System (ADS)

    Le, M.; Mothersill, C. E.; Seymour, C. B.; Ahmad, S. B.; Armstrong, A.; Rainbow, A. J.; McNeill, F. E.

    2015-08-01

    The luminescence intensity of 340+/- 5 nm photons emitted from HaCaT (human keratinocyte) cells was investigated using a single-photon-counting system during cellular exposure to 90Y ?-particles. Multiple factors were assessed to determine their influence upon the quantity and pattern of photon emission from ?-irradiated cells. Exposure of 1× {{10}4} cells/5?mL to 703 ?Ci resulted in maximum UVA photoemission at 44.8× {{10}3}+/- 2.5× {{10}3} counts per second (cps) from live HaCaT cells (background: 1-5 cps); a 16-fold increase above cell-free controls. Significant biophoton emission was achieved only upon stimulation and was also dependent upon presence of cells. UVA luminescence was measured for 90Y activities 14 to 703 ?Ci where a positive relationship between photoemission and 90Y activity was observed. Irradiation of live HaCaT cells plated at various densities produced a distinct pattern of emission whereby luminescence increased up to a maximum at 1× {{10}4} cells/5?mL and thereafter decreased. However, this result was not observed in the dead cell population. Both live and dead HaCaT cells were irradiated and were found to demonstrate different rates of photon emission at low ? activities (?400 ?Ci). Dead cells exhibited greater photon emission rates than live cells which may be attributable to metabolic processes taking place to modulate the photoemissive effect. The results indicate that photon emission from HaCaT cells is perturbed by external stimulation, is dependent upon the activity of radiation delivered, the density of irradiated cells, and cell viability. It is postulated that biophoton emission may be modulated by a biological or metabolic process.

  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. Growth factors in tumor microenvironment

    PubMed Central

    Zhang, Xuejing; Nie, Daotai; Chakrabarty, Subhas

    2012-01-01

    Tumor microenvironment plays a critical role in tumor initiation and progression. Components in the microenvironment can modulate the growth of tumor cells, their ability to progress and metastasize. A major venue of communication between tumor cells and their microenvironment is through polypeptide growth factors and receptors for these growth factors. This article discusses three major classes of growth-stimulatory polypeptide growth factors and receptors for these growth factors. It also discusses how deregulation of these growth factors or their receptors can drive malignant transformation and progression. PMID:20036812

  9. Connective tissue growth factor: expression in human skin in vivo and inhibition by ultraviolet irradiation.

    PubMed

    Quan, Taihao; He, Tianyuan; Kang, Sewon; Voorhees, John J; Fisher, Gary J

    2002-03-01

    Connective tissue growth factor, which is induced by transforming growth factor beta, has been reported to mediate the stimulatory actions of transforming growth factor beta on type I procollagen synthesis. Connective tissue growth factor is expressed in fibrotic disease such as scleroderma, where it is believed to promote abnormal deposition of collagen. Connective tissue growth factor expression has not been described in normal human skin or cultured skin cells, however. We report here that connective tissue growth factor mRNA is constitutively expressed in normal human skin. In situ hybridization demonstrated that connective tissue growth factor mRNA was expressed in keratinocytes throughout the epidermis and in dermal cells. Quantitative real-time reverse transcription polymerase chain reaction revealed that the level of connective tissue growth factor mRNA in the epidermis and dermis of normal human skin was comparable to the level of housekeeping gene 36B4. Ultraviolet irradiation (2 minimal erythema dose, UVB/A2 source) reduced connective tissue growth factor mRNA expression throughout the epidermis and dermis in normal human skin in vivo. Connective tissue growth factor mRNA was reduced (30%) within 4 h post ultraviolet irradiation, and remained reduced (50%) 8-24 h post ultraviolet. Connective tissue growth factor mRNA and protein were also constitutively highly expressed in normal cultured human skin keratinocytes and fibroblasts. Ultraviolet irradiation of cultured normal human skin fibroblasts resulted in a time-dependent inhibition of connective tissue growth factor mRNA expression. At 24 h post ultraviolet, connective tissue growth factor mRNA expression was reduced 80%. Transforming growth factor beta1 rapidly induced connective tissue growth factor mRNA levels (5-fold within 4 h) in skin fibroblasts, but not keratinocytes, and this induction was attenuated 80% by ultraviolet irradiation. Electrophoretic mobility shift assays demonstrated that ultraviolet irradiation reduced protein binding to the transforming growth factor beta/Smad responsiveness elements in the connective tissue growth factor gene promoter, in human skin in vivo and human skin fibroblasts. Constitutive expression of connective tissue growth factor in normal human skin suggests that it is a physiologic regulator of procollagen synthesis. Ultraviolet reduction of connective tissue growth factor expression may contribute to reduced procollagen synthesis observed in ultraviolet-irradiated normal human skin and human skin fibroblasts. PMID:11874477

  10. 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.; Lulli, Daniela; Fidanza, Paolo; Kostyuk, Vladimir A.; De Luca, Chiara; Pastore, Saveria; Korkina, Liudmila G.

    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.

  11. Hepatocyte growth factor controls the proliferation of cultured epidermal melanoblasts and melanocytes from newborn mice.

    PubMed

    Hirobe, Tomohisa; Osawa, Masatake; Nishikawa, Shin-Ichi

    2004-02-01

    Mouse epidermal melanoblasts and melanocytes preferentially proliferated from disaggregated epidermal cell suspensions derived from newborn mouse skin in a serum-free melanocyte-proliferation medium (MDMD) and melanoblast-proliferation medium (MDMDF) supplemented with dibutyryl adenosine 3':5'-cyclic monophosphate (DBcAMP) and/or basic fibroblast growth factor (bFGF). Pure cultured primary melanoblasts and melanocytes were further cultured with MDMD/MDMDF supplemented with hepatocyte growth factor (HGF) from 14 days (keratinocyte depletion). The HGF increased the number of melanoblasts and melanocytes, but not the percentage of differentiated melanocytes in the melanoblast-melanocyte population in the absence of keratinocytes. Flow cytometry analysis showed that melanoblasts and melanocytes in the S and/or G2/M phases of the cell cycle were increased by the treatment with HGF. Moreover, an anti-HGF antibody supplemented to MDMD/MDMDF from the initiation of the primary culture (in the presence of keratinocytes) inhibited the proliferation of melanoblasts and melanocytes, but not the differentiation of melanocytes. These results suggest that HGF is a keratinocyte-derived factor involved in regulating the proliferation of epidermal melanoblasts and melanocytes from newborn mice in cooperation with cAMP elevators and/or bFGF. PMID:14717845

  12. The TRAF-interacting protein (TRIP) is a regulator of keratinocyte proliferation.

    PubMed

    Almeida, Stéphanie; Ryser, Stephan; Obarzanek-Fojt, Magdalena; Hohl, Daniel; Huber, Marcel

    2011-02-01

    The TRAF-interacting protein (TRIP/TRAIP) is a RING-type E3 ubiquitin ligase inhibiting tumor necrosis factor-? (TNF-?)-mediated NF-?B activation. TRIP ablation results in early embryonic lethality in mice. To investigate TRIP function in epidermis, we examined its expression and the effect of TRIP knockdown (KD) in keratinocytes. TRIP mRNA expression was strongly downregulated in primary human keratinocytes undergoing differentiation triggered by high cell density or high calcium. Short-term phorbol-12-myristate-13-acetate (TPA) treatment or inhibition of phosphatidylinositol-3 kinase signaling in proliferative keratinocytes suppressed TRIP transcription. Inhibition by TPA was protein kinase C dependent. Keratinocytes undergoing KD of TRIP expression by lentiviral short-hairpin RNA (shRNA; T4 and T5) had strongly reduced proliferation rates compared with control shRNA. Cell cycle analysis demonstrated that TRIP-KD caused growth arrest in the G1/S phase. Keratinocytes with TRIP-KD resembled differentiated cells consistent with the augmented expression of differentiation markers keratin 1 and filaggrin. Luciferase-based reporter assays showed no increase in NF-?B activity in TRIP-KD keratinocytes, indicating that NF-?B activity in keratinocytes is not regulated by TRIP. TRIP expression was increased by ?2-fold in basal cell carcinomas compared with normal skin. These results underline the important role of TRIP in the regulation of cell cycle progression and the tight linkage of its expression to keratinocyte proliferation. PMID:21068752

  13. Transforming Growth Factor Beta 3 Is Required for Excisional Wound Repair In Vivo

    PubMed Central

    Le, Mark; Naridze, Rachelle; Morrison, Jasmine; Biggs, Leah C.; Rhea, Lindsey; Schutte, Brian C.; Kaartinen, Vesa; Dunnwald, Martine

    2012-01-01

    Wound healing is a complex process that relies on proper levels of cytokines and growth factors to successfully repair the tissue. Of particular interest are the members of the transforming growth factor family. There are three TGF-ß isoforms–TGF- ß 1, 2, and 3, each isoform showing a unique expression pattern, suggesting that they each play a distinct function during development and repair. Previous studies reported an exclusive role for TGF-ß 3 in orofacial development and a potent anti-scarring effect. However, the role of TGF- ß 3 in excisional wound healing and keratinocyte migration remains poorly understood. We tested the effect of TGF-ß 3 levels on excisional cutaneous wounds in the adult mouse by directly injecting recombinant TGF-ß 3 or neutralizing antibody against TGF-ß 3 (NAB) in the wounds. Our results demonstrate that TGF-ß 3 does not promote epithelialization. However, TGF-ß 3 is necessary for wound closure as wounds injected with neutralizing antibody against TGF-ß 3 showed increased epidermal volume and proliferation in conjunction with a delay in keratinocyte migration. Wild type keratinocytes treated with NAB and Tgfb3-deficient keratinocytes closed an in vitro scratch wound with no delay, suggesting that our in vivo observations likely result from a paracrine effect. PMID:23110169

  14. Primary structure of keratinocyte transglutaminase

    SciTech Connect

    Phillips, M.A.; Stewart, B.E.; Qin, Q.; Rice, R.H. ); Chakravarty, R. ); Floyd, E.E.; Jetten, A.M. )

    1990-12-01

    The nucleotide and deduced amino acid sequences of the coding regions of human and rat keratinocyte transglutaminases (protein-glutamine: amine {gamma}-glutamyltransferase; EC 2.3.2.13) have been determined. These yield proteins of {approximately}90 kDa that are 92% identical, indicative of the conservation of important structural features. Alignments of amino acid sequences show substantial similarity among the keratinocyte transglutaminase, human clotting factor XIII catalytic subunit, guinea pig liver tissue transglutaminase, and the human erythrocyte band-4.2 protein. The keratinocyte enzyme is most similar to factor XIII, whereas the band-4.2 protein is most similar to the tissue transglutaminase. A salient feature of the keratinocyte transglutaminase is its 105-residue extension beyond the N terminus of the tissue transglutaminase. This extension and the unreltaed activation peptide of factor XIII (a 37-residue extension) appear to be added for specialized functions after divergence of the tissue transglutaminase from their common lineage.

  15. Maintenance of human skin in organ culture: role for insulin-like growth factor-1 receptor and epidermal growth factor receptor.

    PubMed

    Tavakkol, A; Varani, J; Elder, J T; Zouboulis, C C

    1999-12-01

    Recent studies have shown that adult skin incubated in low-Ca2+ (0.15 mM) medium rapidly degenerates but that normal architecture is maintained when the tissue is incubated in high-Ca2+ medium (1.4 mM Ca2+). To investigate whether the skin cell-produced growth factors insulin-like growth factor-1 (IGF-1) and epidermal growth factor (EGF) play a role in these events, 2-mm skin punch biopsies were obtained and maintained for 8 to 10 days in a basal medium containing 0.15 mM Ca2+ with and without growth factors, or containing 1.4 mM Ca2+ with and without antibodies to the same growth factors. In parallel experiments, cultured human keratinocytes were incubated for 2 days in the same basal medium in the presence or absence of the same growth factors and antibodies. Consistent with previous reports, organ cultures incubated in the low-Ca2+ (0.15 mM) medium rapidly degenerated. Neither IGF-1 nor EGF prevented the complete degeneration of epidermis and dermis in these organ cultures. Interestingly, the addition of an anti-IGF-1 receptor (IGF-1R) antibody to the organ cultures maintained in high-Ca2+ medium induced changes reminiscent of those seen when the organ cultures were maintained in low-Ca2+ medium, i.e. tissue degeneration. In contrast, antibodies to EGF receptor, used for comparison, only produced focal areas of epidermal necrosis. In vitro, IGF-1 is a known mitogen for keratinocytes. In cultured human keratinocytes, anti-IGF-1R antibody partially inhibited the IGF-1-mediated stimulation of human keratinocyte proliferation without affecting normal spontaneous growth. Additionally, IGF-1R immunolocalized to basal keratinocytes in vivo, exhibited specific binding to IGF-1 in vitro. This indicated a critical role for IGF-1R in both organ cultures ex vivo and cultured cells in vitro. Messenger RNA encoding both IGF-1 and IGF-1R were readily detected by RT-PCR in organ cultures incubated in both low- and high-Ca2+ medium. There were no detectable differences in IGF-1 mRNA in organ cultures growing in the low- or high-Ca2+ medium, but lower levels of IGF-1R mRNA were observed in the organ cultures maintained in low-Ca2+ medium than in those in high Ca2+ medium. These findings are consistent with homeostatic changes in the tissue grown under different calcium concentrations. IGF-1 mRNA was detected in several skin cell populations in vitro, even though it was undetectable in cultured keratinocytes. Taken together these findings indicate that (1) the IGF-1/ IGF-1R loop is critically involved in maintenance of human skin organ cultures ex vivo, and (2) IGF-1, locally produced by skin cells other than keratinocytes, interacts with its receptor, predominantly expressed in basal keratinocytes, to maintain tissue homeostasis. PMID:10651165

  16. TG-interacting factor mediates arsenic-induced malignant transformation of keratinocytes via c-Src/EGFR/AKT/FOXO3A and redox signalings.

    PubMed

    Liu, Zi-Miao; Tseng, Hong-Yu; Yeh, Bi-Wen; Wu, Wen-Jeng; Huang, Huei-Sheng

    2015-12-01

    Inorganic arsenic is well known as a carcinogen in human beings. Chronic exposure to inorganic arsenic increases risks of developing some cancers and non-carcinogenic diseases, such as skin lesions in humans. However, the modes of action are not well elucidated. In the present study, HaCaT cells, an immortalized non-tumorigenic human keratinocyte, were continuously exposed to low-dose trivalent arsenic (arsenic trioxide, 0.1 and 0.2 ?M) for at least 4 weeks. We proved that low-dose arsenic could stimulate malignant transformation of HaCaT cells, including increase of cellular proliferation, epithelial-to-mesenchymal transition markers alteration, matrix metalloproteinases activation, invadopodia formation, migration/invasion activities, and anchorage-independent growth. Surprisingly, low-dose arsenic could also transcriptionally increase TG-interacting factor (TGIF) expression via c-Src/EGFR/AKT/FOXO3A signaling involving superoxide production from NADPH oxidase. Moreover, stable overexpression of TGIF could also induce malignant transformation of HaCaT cells. Knockdown of TGIF with its specific shRNA abolished the arsenic-induced effects. Taken together, we suggest that TGIF plays an important role in low-dose arsenic-induced malignant transformation of HaCaT cells, which is regulated by c-Src/EGFR/AKT/FOXO3A pathway and redox signaling. PMID:25537191

  17. Cutaneous manipulation of vascular growth factors leads to alterations in immunocytes, blood vessels and nerves: evidence for a cutaneous neurovascular unit

    PubMed Central

    Ward, Nicole L; Hatala, Denise A; Wolfram, Julie A; Knutsen, Dorothy A.; Loyd, Candace M

    2011-01-01

    Background Skin cells produce soluble factors which influence keratinocyte proliferation, angiogenesis, nerve innervation and immunocyte response. Objective To test the hypothesis that epidermal-dermal interactions influence neural outgrowth, vascular survival, immunocyte recruitment and keratinocyte proliferation. Methods We genetically manipulated the epidermis to express excess vascular endothelial growth factor (VEGF) and/or angiopoietin-1 (Ang1) and then examined the epidermal and dermal phenotypes. We compared these findings with those occurring following overexpression of the Ang1 receptor Tie2 in endothelial cells or keratinocytes. Results Keratinocyte-overexpression of Ang1 resulted in increased epidermal thickness compared to control littermates. Keratinocyte-specific overexpression of Ang1 or VEGF increased dermal angiogenesis compared to control animals and combined Ang1-VEGF lead to further increases. Cutaneous leukocyte examination revealed increases in CD4+ T cell infiltration in mice with keratinocyte-specific overexpression of Ang1, VEGF and Ang1-VEGF combined; in contrast only keratinocyte-specific Ang1 overexpression increased cutaneous F4/80+ macrophage numbers. Interestingly, combined keratinocyte-derived Ang1-VEGF overexpression reduced significantly the number of F4/80+ and Cd11c+ cells compared to mice overexpressing epidermal Ang1 alone. Endothelial cell-specific Tie2 overexpression increased dermal angiogenesis but failed to influence the epidermal and immune cell phenotypes. Keratinocyte-specific Tie2 expressing mice had the highest levels of CD4+, CD8+ and CD11c+ cell numbers and acanthosis compared to all animals. Finally, increases in the number of cutaneous nerves were found in all transgenic mice compared to littermate controls. Conclusion These findings demonstrate that change to one system (vascular or epidermal) results in change to other cutaneous systems and suggest that individual molecules can exert effects on multiple systems. PMID:21129919

  18. MicroRNA-31 Promotes Skin Wound Healing by Enhancing Keratinocyte Proliferation and Migration.

    PubMed

    Li, Dongqing; Li, Xi; Wang, Aoxue; Meisgen, Florian; Pivarcsi, Andor; Sonkoly, Enikö; Ståhle, Mona; Landén, Ning Xu

    2015-06-01

    Wound healing is a basic biological process restoring the integrity of the skin. The role of microRNAs during this process remains largely unexplored. By using an in vivo human skin wound healing model, we show here that the expression of miR-31 is gradually upregulated in wound edge keratinocytes in the inflammatory (1 day after injury) through the proliferative phase (7 days after injury) in comparison with intact skin. In human primary keratinocytes, overexpression of miR-31 promoted cell proliferation and migration, whereas inhibition of miR-31 had the opposite effects. Moreover, we identified epithelial membrane protein 1 (EMP-1) as a direct target of miR-31 in keratinocytes. The expression of EMP-1 in the skin was negatively correlated with the level of miR-31 during wound healing. Silencing of EMP-1 mimicked the effects of overexpression of miR-31 on keratinocyte proliferation and migration, indicating that EMP-1 is a critical target mediating the functions of miR-31 in keratinocytes. Finally, we demonstrated that transforming growth factor-?2, which is highly expressed in skin wounds, upregulated miR-31 expression in keratinocytes. Collectively, we identify miR-31 as a key regulator for promoting keratinocyte proliferation and migration during wound healing. PMID:25685928

  19. Barium promotes anchorage-independent growth and invasion of human HaCaT keratinocytes via activation of c-SRC kinase.

    PubMed

    Thang, Nguyen Dinh; Yajima, Ichiro; Kumasaka, Mayuko Y; Ohnuma, Shoko; Yanagishita, Takeshi; Hayashi, Rumiko; Shekhar, Hossain U; Watanabe, Daisuke; Kato, Masashi

    2011-01-01

    Explosive increases in skin cancers have been reported in more than 36 million patients with arsenicosis caused by drinking arsenic-polluted well water. This study and previous studies showed high levels of barium as well as arsenic in the well water. However, there have been no reports showing a correlation between barium and cancer. In this study, we examined whether barium (BaCl(2)) may independently have cancer-related effects on human precancerous keratinocytes (HaCaT). Barium (5-50 µM) biologically promoted anchorage-independent growth and invasion of HaCaT cells in vitro. Barium (5 µM) biochemically enhanced activities of c-SRC, FAK, ERK and MT1-MMP molecules, which regulate anchorage-independent growth and/or invasion. A SRC kinase specific inhibitor, protein phosphatase 2 (PP2), blocked barium-mediated promotion of anchorage-independent growth and invasion with decreased c-SRC kinase activity. Barium (2.5-5 µM) also promoted anchorage-independent growth and invasion of fibroblasts (NIH3T3) and immortalized nontumorigenic melanocytes (melan-a), but not transformed cutaneous squamous cell carcinoma (HSC5 and A431) and malignant melanoma (Mel-ret) cells, with activation of c-SRC kinase. Taken together, our biological and biochemical findings newly suggest that the levels of barium shown in drinking well water independently has the cancer-promoting effects on precancerous keratinocytes, fibroblast and melanocytes in vitro. PMID:22022425

  20. Interstitial fibrosis and growth factors.

    PubMed Central

    Lasky, J A; Brody, A R

    2000-01-01

    Interstitial pulmonary fibrosis (IPF) is scarring of the lung caused by a variety of inhaled agents including mineral particles, organic dusts, and oxidant gases. The disease afflicts millions of individuals worldwide, and there are no effective therapeutic approaches. A major reason for this lack of useful treatments is that few of the molecular mechanisms of disease have been defined sufficiently to design appropriate targets for therapy. Our laboratory has focused on the molecular mechanisms through which three selected peptide growth factors could play a role in the development of IPF. Hundreds of growth factors and cytokines could be involved in the complex disease process. We are studying platelet-derived growth factor because it is the most potent mesenchymal cell mitogen yet described, transforming growth factor beta because it is a powerful inducer of extracellular matrix (scar tissue) components by mesenchymal cells, and tumor necrosis factor alpha because it is a pleiotropic cytokine that we and others have shown is essential for the development of IPF in animal models. This review describes some of the evidence from studies in humans, in animal models, and in vitro, that supports the growth factor hypothesis. The use of modern molecular and transgenic technologies could elucidate those targets that will allow effective therapeutic approaches. Images Figure 1 Figure 2 PMID:10931794

  1. 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

  2. Dermal fibroblast expression of stromal cell-derived factor-1 (SDF-1) promotes epidermal keratinocyte proliferation in normal and diseased skin.

    PubMed

    Quan, Chunji; Cho, Moon Kyun; Shao, Yuan; Mianecki, Laurel E; Liao, Eric; Perry, Daniel; Quan, Taihao

    2015-12-01

    Stromal cells provide a crucial microenvironment for overlying epithelium. Here we investigated the expression and function of a stromal cell-specific protein, stromal cell-derived factor-1 (SDF-1), in normal human skin and in the tissues of diseased skin. Immunohistology and laser capture microdissection (LCM)-coupled quantitative real-time RT-PCR revealed that SDF-1 is constitutively and predominantly expressed in dermal stromal cells in normal human skin in vivo. To our surprise, an extremely high level of SDF-1 transcription was observed in the dermis of normal human skin in vivo, evidenced by much higher mRNA expression level than type I collagen, the most abundant and highly expressed protein in human skin. SDF-1 was also upregulated in the tissues of many human skin disorders including psoriasis, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC). Double immunostaining for SDF-1 and HSP47 (heat shock protein 47), a marker of fibroblasts, revealed that fibroblasts were the major source of stroma-cell-derived SDF-1 in both normal and diseased skin. Functionally, SDF-1 activates the ERK (extracellular-signal-regulated kinases) pathway and functions as a mitogen to stimulate epidermal keratinocyte proliferation. Both overexpression of SDF-1 in dermal fibroblasts and treatment with rhSDF-1 to the skin equivalent cultures significantly increased the number of keratinocyte layers and epidermal thickness. Conversely, the stimulative function of SDF-1 on keratinocyte proliferation was nearly completely eliminated by interfering with CXCR4, a specific receptor of SDF-1, or by knock-down of SDF-1 in fibroblasts. Our data reveal that extremely high levels of SDF-1 provide a crucial microenvironment for epidermal keratinocyte proliferation in both physiologic and pathologic skin conditions. PMID:26296527

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

    SciTech Connect

    Kurita, Masakazu; Okazaki, Mutsumi; Fujino, Takashi; Takushima, Akihiko; Harii, Kiyonori

    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.

  4. Leveraging growth factor induced macropinocytosis for targeted treatment of lung cancer.

    PubMed

    Iglesias, Raul; Koria, Piyush

    2015-12-01

    Targeted therapy focused on highly expressed growth factor receptors is increasingly becoming popular for the treatment of lung cancer. Cancer cells exhibit higher levels of macropinocytosis than the normally quiescent non-cancerous cells, which can further be enhanced by growth factors. Here, we show the targeted enhancement of macropinocytosis in lung cancer cells for the delivery of the mitochondriotoxic peptide (KLAKLAK)2 using keratinocyte growth factor (KGF). We report the formation of a nanoparticle (NP) comprising of two chimeric fusion proteins, both fused to elastin-like polypeptide (ELP), (KLAKLAK)2-ELP and KGF-ELP. We show that (KLAKLAK)2-ELP nanoparticles are internalized via macropinocytosis and its internalization is facilitated by the interaction of the ELP domain with cell surface heparin sulfate proteoglycans. This internalization leads to mitochondrial depolarization and subsequent cell death. Also, we demonstrate that KGF-ELP selectively enhances macropinocytosis in cancer cells expressing high levels of the keratinocyte growth factor receptor (KGFR). Finally, the heterogeneous NPs consisting of (KLAKLAK)2-ELP and KGF-ELP selectively kill KGFR-expressing lung cancer cells. Hence, this multipronged approach of targeting highly active processes and receptors in cancer cells will be tremendously selective in the treatment of both early-stage and advanced-stage lung cancers, thereby improving patient's prognosis and survival rate. PMID:26519258

  5. Growth factors in orthopedic surgery

    PubMed Central

    Zaharia, C; Despa, N; Simionescu, M; Jinga, V; Fleseriu, I

    2010-01-01

    Growth factors have represented an essential issue of interest for the researchers and clinicians in orthopedics and trauma over the last 40 years. In the last 10 to 15 years, the advances registered in this field have permitted the identification of the most active cellular and humoral factors as well as the improvement of their use in the orthopedic and trauma surgery. Their domain of application has been continuously enlarged and the results have been visible from the beginning. The authors present their appreciation on the actual state of this subject as well as their experience with results and related conclusions. PMID:20302195

  6. Growth factors in orthopedic surgery.

    PubMed

    Zaharia, Comeliu; Niculescu, Marius; Despa, Nicoleta; Simionescu, Maya; Jinga, Victor; Fleseriu, Irina

    2010-01-01

    Growth factors have represented an essential issue of interest for the researchers and clinicians in orthopedics and trauma over the last 40 years. In the last 10 to 15 years, the advances registered in this field have permitted the identification of the most active cellular and humoral factors as well as the improvement of their use in the orthopedic and trauma surgery. Their domain of application has been continuously enlarged and the results have been visible from the beginning. The authors present their appreciation on the actual state of this subject as well as their experience with results and related conclusions. PMID:20302195

  7. 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

  8. Fibroblast growth factor receptor inhibitors.

    PubMed

    Kumar, Suneel B V S; Narasu, Lakshmi; Gundla, Rambabu; Dayam, Raveendra; J A R P, Sarma

    2013-01-01

    Fibroblast growth factor receptors (FGFRs) play an important role in embryonic development, angiogenesis, wound healing, cell proliferation and differentiation. The fibroblast growth factor receptor (FGFR) isoforms have been under intense scrutiny for effective anticancer drug candidates. The fibroblast growth factor (FGF) and its receptor (FGFR) provide another pathway that seems critical to monitoring angiogenesis. Recent findings suggest that FGFR mediates signaling, regulates the PKM2 activity, and plays a crucial role in cancer metabolism. The current review also covers the recent findings on the role of FGFR1 in cancer metabolism. This paper reviews the progress, mechanism, and binding modes of recently known kinase inhibitors such as PD173074, SU series and other inhibitors still under clinical development. Some of the structural classes that will be highlighted in this review include Pyrido[2,3-d]pyrimidines, Indolin- 2-one, Pyrrolo[2,1-f][1,2,4]triazine, Pyrido[2,3-d]pyrimidin-7(8H)-one, and 1,6- Naphthyridin-2(1H)-ones. PMID:23016864

  9. Participation of Gab1 and Gab2 in IL-22-mediated keratinocyte proliferation, migration, and differentiation.

    PubMed

    Zhu, Xiaofang; Li, Zhongliang; Pan, Wenyan; Qin, Lu; Zhu, Guoqiang; Ke, Yuehai; Wu, Jie; Bo, Ping; Meng, Songshu

    2012-10-01

    Interleukin-22 (IL-22) is one of the key mediators of keratinocyte alterations in psoriasis. IL-22 inhibits keratinocyte differentiation and induces the migration of human keratinocytes. Grb2-associated binder 1 (Gab1) has been shown to mediate epidermal growth factor-induced epidermal growth and differentiation via interaction with the Src homology-2-containing protein-tyrosine phosphatase (Shp2). In this investigation, we explore the role of Gab1 and Gab2 in IL-22-mediated keratinocyte activities. We show that both Gab1 and Gab2 were tyrosine phosphorylated in IL-22-stimulated HaCaT cells and human primary epidermal keratinocytes and contributed to the activation of Extracellular signal regulated kinase 1/2 (Erk1/2) through interaction with Shp2. We further demonstrate that HaCaT cells infected with adenoviruses expressing Shp2-binding-defective Gab1/2 mutants exhibited decreased cell proliferation and migration, as well as increased differentiation. Moreover, similar results were observed in HaCaT cells infected with adenovirus-based small interfering RNAs targeting Gab1 and/or Gab2. Altogether, these data underscore the critical roles of Gab1 and Gab2 in IL-22-mediated HaCaT cell proliferation, migration, and differentiation. PMID:22851227

  10. Fibroblast growth factor and hydrocephalus.

    PubMed

    Cuevas, P; Giménez-Gallego, G

    2000-01-01

    The immunohistochemical localization of basic fibroblast growth factor (bFGF) was studied in ventricular ependyma and choroid plexus of aged-matched normotensive and spontaneously hypertensive rats at different ages using a polyclonal antibody against bFGF. The bFGF-like immunoreactivity was observed in brain ependyma and choroid plexus of young and old normotensive rats. However, a progressive loss of immunoreactivity was observed with age in spontaneously hypertensive rats, that was associated with a progressive cerebroventricular dilation. These results show a new neuroendocrine anomaly to be added to the many others previously observed in this rat strain, when they develop hydrocephalus as they age. PMID:10672586

  11. Bone-Derived Growth Factors

    PubMed Central

    Capanna, R.; Campanacci, D.A.; De Biase, P.; Cuomo, P.; Lorenzoni, A.

    2010-01-01

    Bone regeneration is based on the synergy between osteconduction, osteoinduction and osteogenesis. In recent years, we have witnessed the birth and development of numerous osteoconductive substrates, created with the intention of replacing bone grafts, both autologous and homologous. Recently, attention has shifted to osteogenesis, in other words, to the study of mesenchymal cells and their differentiation into osteoblastic cell lines that can be cultured in vitro (as already seen with chondroblasts). Osteoinduction, too, has been shown to be equally important, ever since Urist’s 1967 study which drew attention to the demineralised bone matrix and its properties. The following twenty years led to the definition of bone morphogenetic protein (BMP) and finally to the marketing of the first ostegenic protein (OP-1) obtained by means of the gene recombination technique. The BMPs produced using this technique that, so far, have been shown to be most active are BMP-2 (Infuse) and BMP-7 (Osigraft). The BMPs are not the only molecules with osteoinductive capacity. Other molecules capable of influencing bone regeneration are: platelet-derived growth factors (PDGFs), the transforming growth factor-beta (TGF-?) family, insulin-like growth factor (IGF-I) and the acidic and basic fibroblast growth factors (FGFs). All these growth factors act in synergy with the BMPs, modulating their action and exerting an inductive and proliferative action on the cell lines responsible for regenerating the bone matrix. The literature has been literally invaded by studies, both experimental and preclinical, on these proteins (Termaat, 2005), and they have provided ample demonstration that the BMPs are effective in improving healing of fractures, pseudoarthrosis and spinal fusions. Important advantages of BMPs are the complete absence of risk of transmissible disease, given that they are produced using recombination technology; their purity, and thus absence of an immune response (although such a response could be linked to the carrier used to administer them); their efficacy, which derives from the use of a pre-established dose and not from the individual variability that is a specific feature of demineralized bone matrix homologous bone grafts. In addition to their use in fractures, pseudoarthrosis and spinal fusions, very recent studies are opening up new possibilities which may represent the future field of application of these proteins: Cook et al. (Cook, 2001, Barrack, 2003) have presented the first results obtained using OP-1 in prosthetic revisions carried out in the presence of bone defects; other authors have published a case report on osteonecrosis of the femoral head treated with grafts in association with OP-1; an Italian group is currently experimenting the use of OP-1 in distraction osteogenesis with the aim of speeding up the results that can be obtained using this already well-established technique. However, the most interesting results on the use of recombinant morphogenetic proteins are those obtained by Warnke et al. (2004), maxillo-facial surgeons who, by mixing synthetic spongious bone grafts, bone marrow concentrate and morphogenetic proteins, prepared a new, replacement mandible for implantation in a patient who had lost his own due to cancer, thereby creating new vacularised bone, tailored to that specific patient. The experimental applications of these new drugs are countless and, with regard to their therapeutic potential, the general feeling is that what we are seeing is only the tip of the iceberg. However, it is necessary to ensure that experiments in this field are always geared towards sustainable clinical applications and, to this end, they should be concentrated in a smaller number of centres and conducted in accordance with approved and recognised guidelines.

  12. A Modeling Approach to Study the Effect of Cell Polarization on Keratinocyte Migration

    PubMed Central

    Fuhr, Matthias Jörg; Meyer, Michael; Fehr, Eric; Ponzio, Gilles

    2015-01-01

    The skin forms an efficient barrier against the environment, and rapid cutaneous wound healing after injury is therefore essential. Healing of the uppermost layer of the skin, the epidermis, involves collective migration of keratinocytes, which requires coordinated polarization of the cells. To study this process, we developed a model that allows analysis of live-cell images of migrating keratinocytes in culture based on a small number of parameters, including the radius of the cells, their mass and their polarization. This computational approach allowed the analysis of cell migration at the front of the wound and a reliable identification and quantification of the impaired polarization and migration of keratinocytes from mice lacking fibroblast growth factors 1 and 2 – an established model of impaired healing. Therefore, our modeling approach is suitable for large-scale analysis of migration phenotypes of cells with specific genetic defects or upon treatment with different pharmacological agents. PMID:25671585

  13. REGULAR ARTICLE Growth factor effects on costal chondrocytes for tissue

    E-print Network

    Athanasiou, Kyriacos

    employed five growth factors (insulin-like growth factor-I, transforming growth factor-1, epidermal growthREGULAR ARTICLE Growth factor effects on costal chondrocytes for tissue engineering fibrocartilage factor, platelet-derived growth factor-BB, and basic fibroblast growth factor) in a scaffoldless approach

  14. TGF-beta 1 stimulates expression of keratinocyte integrins during re-epithelialization of cutaneous wounds.

    PubMed

    Gailit, J; Welch, M P; Clark, R A

    1994-08-01

    Epidermal keratinocytes migrate over a provisional matrix during the re-epithelialization of cutaneous wounds. We have investigated the expression of integrins and of transforming growth factor-beta 1 (TGF-beta 1) during re-epithelialization in a porcine model. Tissue specimens were collected at different times after injury and stained with antibodies against subunits of the fibronectin receptor, integrin alpha 5 beta 1, and the vitronectin receptor, integrin alpha v beta 5. Intense staining was observed in the migrating keratinocytes of 5-d wounds; basal and suprabasal cells were stained around the entire cell periphery. Staining returned toward normal levels in 14-d wounds. The appearance of the extracellular form of TGF-beta 1 seemed to be coordinated with the increased expression of integrin subunits: it was detected in migrating keratinocytes and in the adjacent epidermis of early wounds at 5 and 7 d. We also investigated the effect of TGF-beta 1 on cultured epidermal cells. Treating human keratinocytes with TGF-beta 1 increased the levels of mRNA for the integrin subunits alpha 5, alpha v, and beta 5, but had little effect on beta 1. The corresponding cell-surface expression of alpha 5 and alpha v was also increased after treatment. Thus, during wound repair, TGF-beta 1 may induce epidermal keratinocytes to express integrins that facilitate the migratory component of re-epithelialization. PMID:8040614

  15. Staphylococcus aureus keratinocyte invasion is mediated by integrin-linked kinase and Rac1.

    PubMed

    Sayedyahossein, Samar; Xu, Stacey X; Rudkouskaya, Alena; McGavin, Martin J; McCormick, John K; Dagnino, Lina

    2015-02-01

    Staphylococcus aureus is a major component of the skin microbiota and causes a large number of serious infections. S. aureus first interacts with epidermal keratinocytes to breach the epidermal barrier through mechanisms not fully understood. By use of primary keratinocytes from mice with epidermis-restricted Ilk gene inactivation and control integrin-linked kinase (ILK)-expressing littermates, we investigated the role of ILK in epidermal S. aureus invasion. Heat-killed, but not live, bacteria were internalized to Rab5- and Rab7-positive phagosomes, and incubation with keratinocyte growth factor increased their uptake 2.5-fold. ILK-deficient mouse keratinocytes internalized bacteria 2- to 4-fold less efficiently than normal cells. The reduced invasion by live S. aureus of ILK-deficient cells was restored in the presence of exogenous, constitutively active Rac1. Thus, Rac1 functions downstream from ILK during invasion. Further, invasion by S. aureus of Rac1-deficient cells was 2.5-fold lower than in normal cells. Paradoxically, staphylococcal cutaneous penetration of mouse skin explants with ILK-deficient epidermis was 35-fold higher than that of normal skin, indicating defects in epidermal barrier function in the absence of ILK. Thus, we identified an ILK-Rac1 pathway essential for bacterial invasion of keratinocytes, and established ILK as a key contributor to prevent invasive staphylococcal cutaneous infection. PMID:25416549

  16. Growth Factors in Proliferative Diabetic Retinopathy

    PubMed Central

    Khan, Zia Ali

    2003-01-01

    Many growth factors are implicated in the pathogenesis of proliferative diabetic retinopathy. Alteration of growth factors and their receptors in diabetes has been shown in both experimental and clinical studies. Sustained hyperglycemia resulting from long-standing diabetes leads to several biochemical abnormalities that consequently result in retinal hypoxia. Retinal oxygenation state regulates various growth factors that promote angiogenesis in order to meet the oxygen demands of the tissue. However, unregulated expression of these growth factors and induction of complex cascades leading to augmentation of other proangiogenic factors, which may not be regulated by tissue oxygenation, leads to uncontrolled retinal neovascularization and blindness in diabetic patients. PMID:14668050

  17. Genome-wide comparison of human keratinocyte and squamous cell carcinoma responses to UVB irradiation: implications for skin and

    E-print Network

    Domany, Eytan

    To gain insight into the transformation of epidermal cells into squamous carcinoma cells (SCC), we of the CXC/CC subfamilies (e.g. IL-8, GRO-1, -2, -3, SCYA20), growth factors (e.g. HB-EGF, CTGF, INSL-4 compared the response to ultraviolet B radiation (UVB) of normal human epidermal keratinocytes (NHEK

  18. 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

  19. 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

  20. 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

    2015-08-01

    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

  1. Is there a ubiquitous growth factor in the eye? Proliferation induced in different cell types by eye-derived growth factors.

    PubMed

    Barritault, D; Arruti, C; Courtois, Y

    1981-01-01

    In a previous work [1] we showed that a neutral extract of bovine adult retina RE can stimulate the growth and modify the morphology of bovine epithelial lens (BEL) cells in vitro. We were also able to demonstrate that the differences in cell shape are closely related to the cell growth properties induced by RE and are mediated by cytoskeletal protein organization as well as external proteins. In this study, we report the results of further investigations on this retinal extract. We show that it possesses all the characteristics of other growth factors such as promoting proliferation in low serum concentration or of enhancing the colony-forming efficiency of BEL cells considerably. By comparing the morphological response of BEL cells treated with RE with the response of other cells to other growth factors, we propose that the phenotypic modifications are cell specific, but not growth factor specific. We report also that RE has a broad spectrum of activity since it is able to stimulate cells from different origins and species (vascular and corneal endothelial cells, myoblasts, chondrocytes, neuroblastoma cells, and keratinocytes), but not all of them, since it can be toxic for fibroblasts. In this respect, it has an activity similar in many aspects to FGF and EGF, while it differs from them for some target cells. Its action has also been compared with the effects of retinoic acid derivatives and shown to be strikingly different. RE-like activity can be found in other ocular tissues from bovine and other species. The highest growth-promoting capacities were found in extracts of iris, pigmented epithelium with choroid, and vitreous body. The nature of all these extracts has not yet been determined. Since they are prepared in a similar way and since they have similar growth-promoting activity, we postulate that there is an ubiquitous growth factor in the eye called eye-derived growth factor (EDGF) which may play an important role in physiology and pathology of the eye. PMID:6453034

  2. 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.

  3. Interleukin-22 Promotes Wound Repair in Diabetes by Improving Keratinocyte Pro-Healing Functions.

    PubMed

    Avitabile, Simona; Odorisio, Teresa; Madonna, Stefania; Eyerich, Stefanie; Guerra, Liliana; Eyerich, Kilian; Zambruno, Giovanna; Cavani, Andrea; Cianfarani, Francesca

    2015-11-01

    Impaired re-epithelialization, imbalanced expression of cytokines and growth factors, and vascular disease contribute to healing impairment in diabetes. IL-22, a pro-inflammatory cytokine mediating a cross-talk between immune system and epithelial cells, has been shown to have a role in repair processes. In this study we aimed to investigate IL-22 regenerative potential in the poor healing context of diabetic wounds. By using streptozotocin-induced diabetic mice, we demonstrated that IL-22 wound treatment significantly accelerated the healing process, by promoting re-epithelialization, granulation tissue formation, and vascularization. Improved re-epithelialization was associated with increased keratinocyte proliferation and signal transducer and activator of transcription 3 (STAT3) activation. We showed that endogenous IL-22 content was reduced at both mRNA and protein level during the inflammatory phase of diabetic wounds, with fewer IL-22-positive cells infiltrating the granulation tissue. We demonstrated that IL-22 treatment promoted proliferation and injury repair of hyperglycemic keratinocytes and induced activation of STAT3 and extracellular signal-regulated kinase transduction pathways in keratinocytes grown in hyperglycemic condition or isolated from diabetic patients. Finally, we demonstrated that IL-22 treatment was able to inhibit diabetic keratinocyte differentiation while promoting vascular endothelial growth factor release. Our data indicate a pro-healing role of IL-22 in diabetic wounds, suggesting a therapeutic potential for this cytokine in diabetic ulcer management. PMID:26168231

  4. Differentiation of cultured keratinocytes promotes the adherence of Streptococcus pyogenes.

    PubMed Central

    Darmstadt, G L; Fleckman, P; Jonas, M; Chi, E; Rubens, C E

    1998-01-01

    Based on a consideration of the histopathology of nonbullous impetigo that shows localization of Streptococcus pyogenes to highly differentiated, subcorneal keratinocytes, we hypothesized that adherence of an impetigo strain of S. pyogenes would be promoted by terminal differentiation of keratinocytes. An assay was developed in which S. pyogenes adhered via pilus-like projections from the cell wall to the surface of cultured human keratinocytes in a time- and inoculum-dependent manner suggestive of a receptor-mediated process. Terminal differentiation of keratinocytes was induced by increasing the calcium concentration in the growth medium, and was confirmed by morphologic analysis using electron microscopy. Adherence of S. pyogenes was three and fourfold greater to keratinocytes differentiated in 1.0 and 1.5 mM calcium, respectively, compared with undifferentiated keratinocytes in 0.15 mM calcium. The presence of calcium during the adherence assay further enhanced adherence nearly twofold. Adherence occurred preferentially to sites of contact between adjacent keratinocytes, suggesting that the keratinocyte receptor may be a molecule involved in cell-to-cell adhesion. In contrast, nonpathogenic Streptococcus gordonii adhered poorly to keratinocytes regardless of their state of terminal differentiation, and adherence of a pharyngeal strain of S. pyogenes was twofold greater to undifferentiated than differentiated keratinocytes. This is the first report of in vitro adherence of S. pyogenes to keratinocytes in a manner that emulates human impetigo. Adherence of only the impetigo strain, and not the pharyngeal strain of S. pyogenes or the nonpathogenic S. gorgonii isolate, was promoted by keratinocyte differentiation. This result provides a model system for investigating the molecular pathogenesis of streptococcal skin infections. PMID:9421474

  5. Proliferation and motility of HaCaT keratinocyte derivatives is enhanced by fibroblast nemosis.

    PubMed

    Räsänen, Kati; Vaheri, Antti

    2010-06-10

    The role of paracrine tumor-stroma regulation in the progression of cancer is under intense investigation. Activated fibroblasts are key components of the tumor microenvironment providing the soluble factors mediating the regulation. Nemosis is an experimental model to study these parameters: formation of a multicellular spheroid activates fibroblasts and leads to increased production of soluble factors involved in the promotion of growth and motility. Role of nemosis was investigated in the tumorigenesis of HaCaT derivatives representing skin carcinoma progression. Conditioned medium from fibroblast spheroids increased proliferation rate of HaCaT derivatives. Expression of proliferation marker Ki-67 increased significantly in benign A5 and low-grade malignant II-4 cells, but did not further increase in the metastatic RT3 cells. Expression of p63, keratinocyte stem cell marker linked to cancer progression, was augmented by medium from nemotic fibroblasts; this increase was also seen in RT3 cells. Scratch-wound healing of the keratinocytes was enhanced in response to fibroblast nemosis. Neutralizing antibodies against growth factors inhibited wound healing to some extent; the response varied between benign and malignant keratinocytes. Migration and invasion were enhanced by conditioned medium from nemotic fibroblasts in benign and low-grade malignant cells. RT3 keratinocyte migration was further augmented, but invasion was not, indicating their intrinsic capacity to invade. Our data demonstrate that fibroblast nemosis increases proliferation and motility of HaCaT keratinocyte derivatives, and thus nemosis can be used as a model to study the role of soluble factors secreted by fibroblasts in tumor progression. PMID:20097197

  6. Proliferation and motility of HaCaT keratinocyte derivatives is enhanced by fibroblast nemosis

    SciTech Connect

    Raesaenen, Kati; Vaheri, Antti

    2010-06-10

    The role of paracrine tumor-stroma regulation in the progression of cancer is under intense investigation. Activated fibroblasts are key components of the tumor microenvironment providing the soluble factors mediating the regulation. Nemosis is an experimental model to study these parameters: formation of a multicellular spheroid activates fibroblasts and leads to increased production of soluble factors involved in the promotion of growth and motility. Role of nemosis was investigated in the tumorigenesis of HaCaT derivatives representing skin carcinoma progression. Conditioned medium from fibroblast spheroids increased proliferation rate of HaCaT derivatives. Expression of proliferation marker Ki-67 increased significantly in benign A5 and low-grade malignant II-4 cells, but did not further increase in the metastatic RT3 cells. Expression of p63, keratinocyte stem cell marker linked to cancer progression, was augmented by medium from nemotic fibroblasts; this increase was also seen in RT3 cells. Scratch-wound healing of the keratinocytes was enhanced in response to fibroblast nemosis. Neutralizing antibodies against growth factors inhibited wound healing to some extent; the response varied between benign and malignant keratinocytes. Migration and invasion were enhanced by conditioned medium from nemotic fibroblasts in benign and low-grade malignant cells. RT3 keratinocyte migration was further augmented, but invasion was not, indicating their intrinsic capacity to invade. Our data demonstrate that fibroblast nemosis increases proliferation and motility of HaCaT keratinocyte derivatives, and thus nemosis can be used as a model to study the role of soluble factors secreted by fibroblasts in tumor progression.

  7. Development and bioevaluation of nanofibers with blood-derived growth factors for dermal wound healing.

    PubMed

    Bertoncelj, Valentina; Pelipenko, Jan; Kristl, Julijana; Jeras, Matjaž; Cukjati, Marko; Kocbek, Petra

    2014-09-01

    The aim of our work was to produce a modern nanomaterial with incorporated blood-derived growth factors, produced by electrospinning, applicable in treatment of chronic wounds. Platelet-rich plasma was chosen as a natural source of growth factors. Results showed that platelet-rich plasma stimulates keratinocyte and fibroblast cell growth in vitro. Its optimal concentration in growth medium was 2% (v/v) for both types of skin cells, while higher concentrations caused alterations in cell morphology, with reduced cell mobility and proliferation. In the next step hydrophilic nanofibers loaded with platelet-rich plasma were produced from chitosan and poly(ethylene oxide), using electrospinning. The morphology of nanofibers was stable in aqueous conditions for 72 h. It was shown that electrospinning does not adversely affect the biological activity of platelet-rich plasma. The effects of nanofibers with incorporated platelet-rich plasma on cell proliferation, survival, morphology and mobility were examined. Nanofibers limited cell mobility, changed morphology and stimulated cell proliferation. Despite of the small amount of blood-derived growth factors introduced in cell culture via platelet-rich plasma-loaded nanofibers, such nanofibrillar support significantly induced cell proliferation, indicating synergistic effect of nanotopography and incorporated growth factors. The overall results confirm favorable in vitro properties of produced nanofibers, indicating their high potential as a nanomaterial suitable for delivery of platelet-rich plasma in wound healing applications. PMID:24931341

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

    NASA Technical Reports Server (NTRS)

    Vandenburgh, Herman H.

    1993-01-01

    Long-term manned space travel will require a better understanding of skeletal muscle atrophy which results from microgravity. Astronaut strength and dexterity must be maintained for normal mission operations and for emergency situations. Although exercise in space slows the rate of muscle loss, it does not prevent it. A biochemical understanding of how gravity/tension/exercise help to maintain muscle size by altering protein synthesis and/or degradation rate should ultimately allow pharmacological intervention to prevent muscle atrophy in microgravity. The overall objective is to examine some of the basic biochemical processes involved in tension-induced muscle growth. With an experimental in vitro system, the role of exogenous and endogenous muscle growth factors in mechanically stimulated muscle growth are examined. Differentiated avian skeletal myofibers can be 'exercised' in tissue culture using a newly developed dynamic mechanical cell stimulator device which simulates different muscle activity patterns. Patterns of mechanical activity which significantly affect muscle growth and metabolic characteristics were found. Both exogenous and endogenous growth factors are essential for tension-induced muscle growth. Exogenous growth factors found in serum, such as insulin, insulin-like growth factors, and steroids, are important regulators of muscle protein turnover rates and mechanically-induced muscle growth. Endogenous growth factors are synthesized and released into the culture medium when muscle cells are mechanically stimulated. At least one family of mechanically induced endogenous factors, the prostaglandins, help to regulate the rates of protein turnover in muscle cells. Endogenously synthesized IGF-1 is another. The interaction of muscle mechanical activity and these growth factors in the regulation of muscle protein turnover rates with our in vitro model system is studied.

  9. Growth factors from genes to clinical application

    SciTech Connect

    Sara, V.R. ); Hall, K.; Low, H. )

    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.

  10. 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.

  11. Evaluation of emulsion electrospun polycaprolactone/hyaluronan/epidermal growth factor nanofibrous scaffolds for wound healing.

    PubMed

    Wang, Zhenbei; Qian, Yuna; Li, Linhao; Pan, Lianhong; Njunge, Lucy W; Dong, Lili; Yang, Li

    2016-01-01

    Wound healing scaffolds provide cells with structural integrity and can also deliver biological agents to establish a skin tissue-specific microenvironment to regulate cell functions and to accelerate the healing process. In this study, we fabricated biodegradable nanofibrous scaffolds with an emulsion electrospinning technique. The scaffolds were composed of polycaprolactone, hyaluronan and encapsulating epidermal growth factor. The morphology and core-sheath structure of the nanofibers were characterized by scanning electron microscopy and transmission electron microscopy. The scaffolds were also characterized for chemical composition and hydrophilicity with a Fourier-transform infrared analysis, energy dispersive spectroscopy and the water contact angle. An in vitro model protein bovine serum albumin and epidermal growth factor release study was conducted to evaluate the sustained release potential of the core-sheath structured nanofibers with and without the hyaluronan component. Additionally, an in vitro cultivation of human skin keratinocytes (HaCaT) and fibroblasts on polycaprolactone/hyaluronan and polycaprolactone/hyaluronan-epidermal growth factor scaffolds showed a significant synergistic effect of hyaluronan and epidermal growth factor on cell proliferation and infiltration. Furthermore, there was an up-regulation of the wound-healing-related genes collagen I, collagen III and TGF-? in polycaprolactone/hyaluronan/epidermal growth factor scaffolds compared with control groups. In the full-thickness wound model, the enhanced regeneration of fully functional skin was facilitated by epidermal regeneration in the polycaprolactone/hyaluronan/epidermal growth factor treatment group. Our findings suggest that bioactivity and hemostasis of the hyaluronan-based nanofibrous scaffolds have the capability to encapsulate and control the release of growth factors that can serve as skin tissue engineering scaffolds for wound healing. PMID:26012354

  12. New Clue Found to Growth Factor Action.

    ERIC Educational Resources Information Center

    Hoffman, Michelle

    1991-01-01

    Discussed is the discovery which may help to explain epidermal growth factor effects on the cell skeleton. The role of a protein called profilin in the regulation of the microfilament system is described. (CW)

  13. Acidic fibroblast growth factor promotes vascular repair.

    PubMed Central

    Bjornsson, T D; Dryjski, M; Tluczek, J; Mennie, R; Ronan, J; Mellin, T N; Thomas, K A

    1991-01-01

    Intravascular injury to arteries can result in thickening of the intimal smooth muscle layer adjacent to the lumen by migration and proliferation of cells from the underlying medial smooth muscle layer accompanied by deposition of extracellular matrix. This pathological response, which decreases lumen diameter, might, in part, be the result of the access of smooth muscle cells to plasma and platelet-derived growth factors as a consequence of denudation of the overlying confluent monolayer of vascular endothelial cells. Injured rat carotid arteries were treated by i.v. administration of acidic fibroblast growth factor, a heparin-binding protein that is chemotactic and mitogenic for vascular endothelial cells. The growth factor treatment resulted in dose-dependent inhibition of intimal thickening with parallel promotion of endothelial regeneration over the injured area. Therefore, acidic fibroblast growth factor might be efficacious in the prevention of restenosis caused by intimal thickening following angioplasty in humans. Images PMID:1717983

  14. Activin controls skin morphogenesis and wound repair predominantly via stromal cells and in a concentration-dependent manner via keratinocytes.

    PubMed

    Bamberger, Casimir; Schärer, Agnes; Antsiferova, Maria; Tychsen, Birte; Pankow, Sandra; Müller, Mischa; Rülicke, Thomas; Paus, Ralf; Werner, Sabine

    2005-09-01

    The transforming growth factor-beta family member activin is a potent regulator of skin morphogenesis and repair. Transgenic mice overexpressing activin in keratinocytes display epidermal hyper-thickening and dermal fibrosis in normal skin and enhanced granulation tissue formation after wounding. Mice overexpressing the secreted activin antagonist follistatin, however, have the opposite wound-healing phenotype. To determine whether activin affects skin morphogenesis and repair via activation of keratinocytes and/or stromal cells, we generated transgenic mice expressing a dominant-negative activin receptor IB mutant (dnActRIB) in keratinocytes. The architecture of adult skin was unaltered in these mice, but delays were observed in postnatal pelage hair follicle morphogenesis and in the first catagen-telogen transformation of hair follicles. Although dnActRIB-transgenic mice showed slightly delayed wound re-epithelialization after skin injury, the strong inhibition of granulation tissue formation seen in follistatin-transgenic mice was not observed. Therefore, although endogenous activin appeared to affect skin morphogenesis and repair predominantly via stromal cells, overexpressed activin strongly affected the epidermis. The epidermal phenotype of activin-overexpressing mice was partially rescued by breeding these animals with dnActRIB-transgenic mice. These results demonstrate that activin affects both stromal cells and keratinocytes in normal and wounded skin and that the effect on keratinocytes is dose-dependent in vivo. PMID:16127153

  15. 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...

  16. Constraining the growth factor with baryon oscillations

    E-print Network

    Domenico Sapone; Luca Amendola

    2007-09-18

    The growth factor of linear fluctuations is probably one of the least known quantity in observational cosmology. Here we discuss the constraints that baryon oscillations in galaxy power spectra from future surveys can put on a conveniently parametrized growth factor. We find that spectroscopic surveys of $5000 deg^2$ extending to $z \\approx 3$ could estimate the growth index $\\gamma$ within 0.06; a similar photometric survey would give $\\Delta\\gamma\\approx 0.15$. This test provides an important consistency check for standard cosmological model and could constrain modified gravity models. We discuss the errors and the figure of merit for various combinations of redshift errors and survey size.

  17. Activated protein C: A regulator of human skin epidermal keratinocyte function

    PubMed Central

    McKelvey, Kelly; Jackson, Christopher John; Xue, Meilang

    2014-01-01

    Activated protein C (APC) is a physiological anticoagulant, derived from its precursor protein C (PC). Independent of its anticoagulation, APC possesses strong anti-inflammatory, anti-apoptotic and barrier protective properties which appear to be protective in a number of disorders including chronic wound healing. The epidermis is the outermost skin layer and provides the first line of defence against the external environment. Keratinocytes are the most predominant cells in the epidermis and play a critical role in maintaining epidermal barrier function. PC/APC and its receptor, endothelial protein C receptor (EPCR), once thought to be restricted to the endothelium, are abundantly expressed by skin epidermal keratinocytes. These cells respond to APC by upregulating proliferation, migration and matrix metalloproteinase-2 activity and inhibiting apoptosis/inflammation leading to a wound healing phenotype. APC also increases barrier function of keratinocyte monolayers by promoting the expression of tight junction proteins and re-distributing them to cell-cell contacts. These cytoprotective properties of APC are mediated through EPCR, protease-activated receptors, epidermal growth factor receptor or Tie2. Future preventive and therapeutic uses of APC in skin disorders associated with disruption of barrier function and inflammation look promising. This review will focus on APC’s function in skin epidermis/keratinocytes and its therapeutical potential in skin inflammatory conditions. PMID:24921007

  18. Keratinocyte Microvesicles Regulate the Expression of Multiple Genes in Dermal Fibroblasts.

    PubMed

    Huang, Ping; Bi, Jiarui; Owen, Gethin R; Chen, Weimin; Rokka, Anne; Koivisto, Leeni; Heino, Jyrki; Häkkinen, Lari; Larjava, Hannu

    2015-12-01

    Extracellular vesicles released from cells regulate many normal and pathological conditions. Little is known about the role of epidermal keratinocyte microvesicles (KC-MVs) in epithelial-stromal interaction that is essential for wound healing. We investigated, therefore, whether MV-like structures are present in human wounds and whether they affect wound healing-associated gene expression in dermal fibroblasts. In human wounds, MV-like vesicles were observed during active epithelial migration and early granulation tissue formation. When KC-MVs derived from keratinocyte-like cells (HaCaT) were added to fibroblast cultures, expression of 21 genes was significantly regulated (P<0.05) out of 80 genes investigated, including matrix metalloproteinase-1 and -3, interleukin-6 and -8, and genes associated with transforming growth factor-? signaling. Similar changes were observed at the protein level. MVs from normal epidermal keratinocytes showed similar response to HaCaT cells. KC-MVs activated ERK1/2, JNK, Smad, and p38 signaling pathways in fibroblasts with ERK1/2 signaling having the most prominent role in the MV-induced gene expression changes. KC-MVs stimulated fibroblast migration and induced fibroblast-mediated endothelial tube formation but did not affect collagen gel contraction by fibroblasts. The results demonstrate that keratinocyte microvesicles have a strong and a specific regulatory effect on fibroblasts that may modulate several aspects of wound healing. PMID:26288358

  19. Luteolin inhibits human keratinocyte activation and decreases NF-?B induction that is increased in psoriatic skin.

    PubMed

    Weng, Zuyi; Patel, Arti B; Vasiadi, Magdalini; Therianou, Anastasia; Theoharides, Theoharis C

    2014-01-01

    Psoriasis (Ps) is an autoimmune disease characterized by keratinocyte hyperproliferation and chronic inflammation, with increased expression of tumor necrosis factor (TNF) and vascular endothelial growth factor (VEGF). Anti-TNF biologic agents are effective in treating Ps, but are associated with increased risk of infections and blood malignancies. Moreover, keratinocyte hyperproliferation and activation have yet to be addressed. Flavonoids, such as luteolin, are natural compounds with potent anti-inflammatory properties, but their actions on keratinocytes remain unknown. We show that TNF (50 ng/mL) triggers significant production of inflammatory mediators interleukin-6, interleukin-8 and VEGF from both human HaCaT and primary keratinocytes. Pretreatment with the flavonoid luteolin (10-100 µM) significantly inhibits mRNA expression and release of all three mediators in a concentration-dependent manner. More importantly, luteolin decreases TNF-induced phosphorylation, nuclear translocation and DNA binding of the nuclear factor-kappa B (NF-?B) typically involved in inflammatory mediator transcription. We also report that luteolin reduces TNF-induced mRNA expression of two genes (NFKB1 and RELA) encoding two NF-?B subunits (NF-?B p50 and NF-?B p65, respectively). Interestingly, we show that gene expression of RELA is increased in human psoriatic skin. Keratinocyte proliferation, which is a characteristic feature of psoriatic skin, is effectively reduced by luteolin in HaCaT cells, but not in primary keratinocytes. Finally, luteolin does not affect intracellular ATP production or viability. Appropriate formulations of luteolin and related flavones may be promising candidates to be developed into local and systemic treatments for Ps and other inflammatory skin diseases. PMID:24587411

  20. INTRODUCTION The fibroblast growth factors (FGFs) constitute a large family

    E-print Network

    Perrimon, Norbert

    INTRODUCTION The fibroblast growth factors (FGFs) constitute a large family of proteins that act glycosaminoglycans are involved in signaling by fibroblast growth factor receptors, but evidence. Consistent with an involvement of Sulfateless and Sugarless in fibroblast growth factor receptor signaling

  1. Differentiation-specific increase in ALA-induced protoporphyrin IX accumulation in primary mouse keratinocytes.

    PubMed Central

    Ortel, B.; Chen, N.; Brissette, J.; Dotto, G. P.; Maytin, E.; Hasan, T.

    1998-01-01

    A treatment regimen that takes advantage of the induction of intracellular porphyrins such as protoporphyrin IX (PPIX) by exposure to exogenous 5-amino-laevulinic acid (ALA) followed by localized exposure to visible light represents a promising new approach to photodynamic therapy (PDT). Acting upon the suggestion that the effectiveness of ALA-dependent PDT may depend upon the state of cellular differentiation, we investigated the effect of terminal differentiation upon ALA-induced synthesis of and the subsequent phototoxicity attributable to PPIX in primary mouse keratinocytes. Induction of keratinocyte differentiation augmented intracellular PPIX accumulation in cells treated with ALA. These elevated PPIX levels resulted in an enhanced lethal photodynamic sensitization of differentiated cells. The differentiation-dependent increase in cellular PPIX levels resulted from several factors including: (a) increased ALA uptake, (b) enhanced PPIX production and (c) decreased PPIX export into the culture media. Simultaneously, steady-state levels of coproporphyrinogen oxidase mRNA increased but aminolaevulinic acid dehydratase mRNA levels remained unchanged. From experiments using 12-o-tetradecanoylphorbol-13-acetate, transforming growth factor beta 1 and calcimycin we demonstrated that the increase in PPIX concentration in terminally differentiating keratinocytes is calcium- and differentiation specific. Stimulation of the haem synthetic capacity is seen in primary keratinocytes, but not in PAM 212 cells that fail to undergo differentiation. Interestingly, increased PPIX formation and elevated coproporphyrinogen oxidase mRNA levels are not limited to differentiating keratinocytes; these were also elevated in the C2C12 myoblast and the PC12 adrenal cell lines upon induction of differentiation. Overall, the therapeutic implications of these results are that the effectiveness of ALA-dependent PDT depends on the differentiation status of the cell and that this may enable selective targeting of several tissue types. Images Figure 7 PMID:9667642

  2. Evidence for nerve growth factor-mediated paracrine effects in human epidermis.

    PubMed

    Yaar, M; Grossman, K; Eller, M; Gilchrest, B A

    1991-11-01

    Nerve growth factor (NGF) is critical to the development and maintenance of the peripheral nervous system, but its possible roles in other organ systems are less well characterized. We have recently shown that human epidermal melanocytes, pigment cells derived from the neural crest, express the NGF receptor (p75 NGF-R) in vitro (Peacocke, M., M. Yaar, C. P. Mansur, M. V. Chao, and B. A. Gilchrest. 1988. Proc. Natl. Acad. Sci. USA. 85:5282-5286). Using cultured human skin-derived cells we now demonstrate that the melanocyte p75 NGF-R is functional, in that NGF stimulation modulates melanocyte gene expression; that exposure to an NGF gradient is chemotactic for melanocytes and enhances their dendricity; and that keratinocytes, the dominant epidermal cell type, express NGF messenger RNA and hence are a possible local source of NGF for epidermal melanocytes in the skin. These combined data suggest a paracrine role for NGF in human epidermis. PMID:1655813

  3. Hematopoietic growth factors: current knowledge, future prospects.

    PubMed

    Demetri, G D

    1992-01-01

    The introduction of hematopoietic growth factors into clinical medicine represents one of the more exciting developments in oncology in the past several years. The identification, gene cloning, and large-scale production of hematopoietic growth factors represent important examples of the practical benefits that may accrue from application of the sophisticated technology derived from recombinant DNA research. Research, both at the bench and by the bedside, has proceeded at an extraordinarily rapid pace in this field over the past five years, leading to an abundance of new information, novel promising agents, and important clinical controversies related to the biology and appropriate clinical applications of hematopoietic growth factors. With these agents, for the first time in history, the production of human blood cells can be systematically manipulated in vivo in an effort to optimize physiology beyond the endogenous host response. Additionally, investigators utilizing purified hematopoietic growth factors as reagents may provide crucial insights into the mechanisms of blood cell production in health and in various disease states. This review aims to summarize the current state of knowledge regarding the control of blood cell production by specific factors and to put these data in the context of clinical medicine. The emphasis will be on factors that primarily influence myeloid (rather than lymphoid) cell growth, differentiation, and activation, and the clinical focus will be on applications in oncologic therapeutics and in the treatment of primary hematologic disorders. By reviewing what we know and what has already been done, we may be better able to define the important questions that remain and to formulate the means to answer our current uncertainties about the activities and clinical uses of hematopoietic growth factors. PMID:1382921

  4. Growth factor parametrization in curved space

    E-print Network

    Yungui Gong; Mustapha Ishak; Anzhong Wang

    2009-07-01

    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 $\\Omega_{m}^\\gamma$ and then suggest a new form, $f_a=\\Omega_m^\\gamma+(\\gamma-4/7)\\Omega_k$, as an approximation for the growth factor when the curvature $\\Omega_k$ 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 $\\Omega_{m0}$ and $\\Omega_{k0}$ to the expansion/distance measurements from Type Ia supernovae, baryon acoustic oscillation, WMAP5, and $H(z)$ data, we fit the growth index parameter to current growth factor data and obtain $\\gamma_{\\Lambda}(\\Omega_{k} \

  5. Growth factor parametrization and modified gravity

    E-print Network

    Yungui Gong

    2008-12-16

    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 the cosmic acceleration. The growth rate is parametrized by the growth index $\\gamma$. We discuss the dependence of $\\gamma$ on the matter energy density $\\Omega$ and its current value $\\Omega_0$ for a more accurate approximation of the growth factor. The observational data, including the data of the growth rate, are used to fit different models. The data strongly disfavor the Dvali-Gabadadze-Porrati model. For the dark energy model with a constant equation of state, we find that $\\Omega_0=0.27\\pm 0.02$ and $w=-0.97\\pm 0.09$. For the $\\Lambda$CDM model, we find that $\\gamma=0.64^{+0.17}_{-0.15}$. For the Dvali-Gabadadze-Porrati model, we find that $\\gamma=0.55^{+0.14}_{-0.13}$.

  6. Vascular endothelial growth factor B, a novel growth factor for endothelial cells.

    PubMed Central

    Olofsson, B; Pajusola, K; Kaipainen, A; von Euler, G; Joukov, V; Saksela, O; Orpana, A; Pettersson, R F; Alitalo, K; Eriksson, U

    1996-01-01

    We have isolated and characterized a novel growth factor for endothelial cells, vascular endothelial growth factor B (VEGF-B), with structural similarities to vascular endothelial growth factor (VEGF) and placenta growth factor. VEGF-B was particularly abundant in heart and skeletal muscle and was coexpressed with VEGF in these and other tissues. VEGF-B formed cell-surface-associated disulfide-linked homodimers and heterodimerized with VEGF when coexpressed. Conditioned medium from transfected 293EBNA cells expressing VEGF-B stimulated DNA synthesis in endothelial cells. Our results suggest that VEGF-B has a role in angiogenesis and endothelial cell growth, particularly in muscle. Images Fig. 3 Fig. 4 Fig. 5 PMID:8637916

  7. 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.; Robertson, L.W.; Department of Occupational and Environmental Health, The University of Iowa, Iowa City, IA ; Ludewig, G.

    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.

  8. 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

  9. 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

  10. Novel method for isolating human melanoblasts from keratinocyte culture.

    PubMed

    Cho, Eun-Gyung; Bin, Bum-Ho; Choi, Hyunjung; Park, Phil June; Kang, Hak Hee; Lee, Tae Ryong

    2014-05-01

    The characterization of melanoblasts is important for understanding their in vivo development, melanoma formation, and pigment-related disorders. However, no methods have been reported for the isolation of melanoblasts from human skin. Using a 'calcium-pulse' technique, involving the differentiation of human keratinocytes with high calcium and the subsequent spontaneous separation of the epidermal sheets, we effectively isolated human melanoblasts (keratinocyte-adapted melanoblasts, KaMBs) from keratinocyte culture. The KaMBs expressed early melanogenesis-related genes, including BRN2, which is a known melanoblast marker. Moreover, the KaMBs displayed much higher proliferative and growth capacities than the primary melanocytes. Considering that keratinocytes might provide an in vivo-like environment for KaMBs during isolation and in vitro culture, the 'calcium-pulse' technique offers an unprecedented, easy, and efficient method for the isolation of human melanoblasts, retaining the original characteristics of these cells. PMID:24460991

  11. Vigilant Keratinocytes Trigger Pathogen-Associated Molecular Pattern Signaling in Response to Streptococcal M1 Protein.

    PubMed

    Persson, Sandra T; Wilk, Laura; Mörgelin, Matthias; Herwald, Heiko

    2015-12-01

    The human skin exerts many functions in order to maintain its barrier integrity and protect the host from invading microorganisms. One such pathogen is Streptococcus pyogenes, which can cause a variety of superficial skin wounds that may eventually progress into invasive deep soft tissue infections. Here we show that keratinocytes recognize soluble M1 protein, a streptococcal virulence factor, as a pathogen-associated molecular pattern to release alarming inflammatory responses. We found that this interaction initiates an inflammatory intracellular signaling cascade involving the activation of the mitogen-activated protein kinases extracellular signal-regulated kinase (ERK), p38, and Jun N-terminal protein kinase and the subsequent induction and mobilization of the transcription factors NF-?B and AP-1. We also determined the imprint of the inflammatory mediators released, such as interleukin-8 (IL-8), growth-related oncogene alpha, migration inhibitory factor, extracellular matrix metalloproteinase inducer, IL-1?, IL-1 receptor a, and ST2, in response to streptococcal M1 protein. The expression of IL-8 is dependent on Toll-like receptor 2 activity and subsequent activation of the mitogen-activated protein kinases ERK and p38. Notably, this signaling seems to be distinct for IL-8 release, and it is not shared with the other inflammatory mediators. We conclude that keratinocytes participate in a proinflammatory manner in streptococcal pattern recognition and that expression of the chemoattractant IL-8 by keratinocytes constitutes an important protective mechanism against streptococcal M1 protein. PMID:26416902

  12. The Effects of Recombinant Human Insulin-like Growth Factor-I/Insulin-like Growth Factor Binding

    E-print Network

    The Effects of Recombinant Human Insulin-like Growth Factor-I/Insulin-like Growth Factor Binding Research Institute, University of Southampton, Southampton, UK Context: Insulin-like growth factor-I (IGF anabolic agents (3, 4). Insulin-like growth factor-I (IGF-I) mediates many of the anabolic ac- tions of GH

  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. The epithelial-mesenchymal transition induced by keratinocyte growth conditions is overcome by E6 and E7 from HPV16, but not HPV8 and HPV38: Characterization of global transcription profiles

    SciTech Connect

    Azzimonti, Barbara; Dell'Oste, Valentina; Borgogna, Cinzia; Mondini, Michele; Gugliesi, Francesca; De Andrea, Marco; Chiorino, Giovanna; Scatolini, Maria; Ghimenti, Chiara; Landolfo, Santo; Gariglio, Marisa

    2009-06-05

    The aim of this study was to evaluate the growth properties of primary human keratinocytes expressing E6 and E7 proteins, which are from either the beta- or alpha-genotypes, under different culture conditions. We demonstrated that keratinocytes expressing E6 and E7, from both HPV8 and 38, irreversibly underwent the epithelial-mesenchymal transition (EMT) when grown on plastic with FAD medium (F12/DMEM/5%FBS). Expression of E6/E7 from HPV16 was capable of fully overcoming the FAD-induced EMT. Immortalization was only observed in HPV16-transduced cell lines, while the more proliferating phenotype of both KerHPV8 and 38 was mainly related to FAD-induced EMT. Microarray analysis of exponentially growing cells identified 146 cellular genes that were differentially regulated in HPV16 compared to HPV8- and 38-transduced cells. A large accumulation of transcripts associated with epidermal development and differentiation was observed in HPV16-transduced cells, whereas transcripts of genes involved in the extracellular matrix, multicellular organismal processes, and inflammatory response were affected in HPV8 and 38-transduced cells.

  15. 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

  16. Growth Factors and Tension-Induced Skeletal Muscle Growth

    NASA Technical Reports Server (NTRS)

    Vandenburgh, Herman H.

    1994-01-01

    The project investigated biochemical mechanisms to enhance skeletal muscle growth, and developed a computer based mechanical cell stimulator system. The biochemicals investigated in this study were insulin/(Insulin like Growth Factor) IGF-1 and Steroids. In order to analyze which growth factors are essential for stretch-induced muscle growth in vitro, we developed a defined, serum-free medium in which the differentiated, cultured avian muscle fibers could be maintained for extended periods of time. The defined medium (muscle maintenance medium, MM medium) maintains the nitrogen balance of the myofibers for 3 to 7 days, based on myofiber diameter measurements and myosin heavy chain content. Insulin and IGF-1, but not IGF-2, induced pronounced myofiber hypertrophy when added to this medium. In 5 to 7 days, muscle fiber diameters increase by 71 % to 98% compared to untreated controls. Mechanical stimulation of the avian muscle fibers in MM medium increased the sensitivity of the cells to insulin and IGF-1, based on a leftward shift of the insulin dose/response curve for protein synthesis rates. (54). We developed a ligand binding assay for IGF-1 binding proteins and found that the avian skeletal muscle cultures produced three major species of 31, 36 and 43 kD molecular weight (54) Stretch of the myofibers was found to have no significant effect on the efflux of IGF-1 binding proteins, but addition of exogenous collagen stimulated IGF-1 binding protein production 1.5 to 5 fold. Steroid hormones have a profound effect on muscle protein turnover rates in vivo, with the stress-related glucocorticoids inducing rapid skeletal muscle atrophy while androgenic steroids induce skeletal muscle growth. Exercise in humans and animals reduces the catabolic effects of glucocorticoids and may enhance the anabolic effects of androgenic steroids on skeletal muscle. In our continuing work on the involvement of exogenrus growth factors in stretch-induced avian skeletal muscle growth, we have performed experiments to determine whether mechanical stimulation of cultured avian muscle cells alters their response to anabolic steroids or glucocorticoids. In static cultures, testosterone had no effect on muscle cell growth, but 5alpha-dihydrotestosterone and the synthetic steroid stanozolol increased cell growth by up to 18% and 30%, respectively, after a three day exposure. We completed development of a new IBM-based mechanical cell stimulator system to provide greater flexibility in operating and monitoring our experiments. Our previous long term studies on myofiber growth were designed around a perfusion system of our own design. We have recently changed to performing these studies using a modified CELLCO cartridge bioreactor system Z since it has been certified as the ground-based model for the Shuttle's Space Tissue Loss (STL) F= Cell Culture Module. The current goals of this aspect of the project are three fold: 1) to design a Z cell culture system for studying avian skeletal myofiber atrophy on the Shuttle and Space Station; 0 2) to expand the use of bioreactors to cells which do not grow in either suspension or attached to the hollow fibers; and 3) to combine the bioreactor system with our computerized mechanical cell stimulator to have a better in vitro model to study tension/gravity/stretch regulation of skeletal muscle size. Preliminary studies also reported on involved : (1) how release of tension can induce rapid atrophy of tissues cultured avian skeletal muscle cells, and (2) a mechanism to transfer and maintain avian skeletal muscle organoids in modified cartridges in the Space Tissue Loss Module.

  17. Ocular Angiogenesis: Vascular Endothelial Growth Factor and Other Factors.

    PubMed

    Rubio, Roman G; Adamis, Anthony P

    2016-01-01

    Systematic study of the mechanisms underlying pathological ocular neovascularization has yielded a wealth of knowledge about pro- and anti-angiogenic factors that modulate diseases such as neovascular age-related macular degeneration. The evidence implicating vascular endothelial growth factor (VEGF) in particular has led to the development of a number of approved anti-VEGF therapies. Additional proangiogenic targets that have emerged as potential mediators of ocular neovascularization include hypoxia-inducible factor-1, angiopoietin-2, platelet-derived growth factor-B and components of the alternative complement pathway. As for VEGF, knowledge of these factors has led to a product pipeline of many more novel agents that are in various stages of clinical development in the setting of ocular neovascularization. These agents are represented by a range of drug classes and, in addition to novel small- and large-molecule VEGF inhibitors, include gene therapies, small interfering RNA agents and tyrosine kinase inhibitors. In addition, combination therapy is beginning to emerge as a strategy to improve the efficacy of individual therapies. Thus, a variety of agents, whether administered alone or as adjunctive therapy with agents targeting VEGF, offer the promise of expanding the range of treatments for ocular neovascular diseases. PMID:26502333

  18. Human keratinocyte culture from the peritonsillar mucosa.

    PubMed

    Neugebauer, P; Bonnekoh, B; Wevers, A; Michel, O; Mahrle, G; Krieg, T; Stennert, E

    1996-01-01

    Tonsillectomy tissue can be used as a routine source for cultures of oropharyngeal keratinocytes. In so doing, a peritonsillar strip of unaltered mucosa was dissected in the upper submucosa. Subsequent trypsinization yielded 7.0 +/- 3.4 x 10(6) keratinocytes per bilateral tonsillectomy. Keratinocyte attachment and growth in primary culture were promoted by sublethally irradiated 3T3 murine fibroblasts. Three subcultures could be performed without a feeder layer and were characterized by a population doubling time of 4.5 days during log growth phase. Electrophoretic and immunoblot analysis of the third subculture revealed a strong expression of keratin pairs 5/14 and 6/16 as well as keratins 7 and 19, whereas keratins 8/18 were expressed less intensely. The lowest intensity, was found for keratin 13, which is known to be indicative of the differentiated mucosa. The culture technique thus provides an easily available in vitro model for morphological and functional studies on the epithelial compartment of human oropharyngeal mucosa. PMID:8737778

  19. Vascular Endothelial Growth Factor and Angiogenesis in the Regulation of Cutaneous Wound Repair

    PubMed Central

    Johnson, Kelly E.; Wilgus, Traci A.

    2014-01-01

    Significance: Angiogenesis, the growth of new blood vessels from existing vessels, is an important aspect of the repair process. Restoration of blood flow to damaged tissues provides oxygen and nutrients required to support the growth and function of reparative cells. Vascular endothelial growth factor (VEGF) is one of the most potent proangiogenic growth factors in the skin, and the amount of VEGF present in a wound can significantly impact healing. Recent Advances: The activity of VEGF was once considered to be specific for endothelial cells lining the inside of blood vessels, partly because VEGF receptor (VEGFR) expression was believed to be restricted to endothelial cells. It is now known, however, that VEGFRs can be expressed by a variety of other cell types involved in wound repair. For example, keratinocytes and macrophages, which both carry out important functions during wound healing, express VEGFRs and are capable of responding directly to VEGF. Critical Issues: The mechanisms by which VEGF promotes angiogenesis are well established. Recent studies, however, indicate that VEGF can directly affect the activity of several nonendothelial cell types present in the skin. The implications of these extra-angiogenic effects of VEGF on wound repair are not yet known, but they suggest that this growth factor may play a more complex role during wound healing than previously believed. Future Directions: Despite the large number of studies focusing on VEGF and wound healing, it is clear that the current knowledge of how VEGF contributes to the repair of skin wounds is incomplete. Further research is needed to obtain a more comprehensive understanding of VEGF activities during the wound healing process. PMID:25302139

  20. Immunosuppressive cyclosporin A activates AKT in keratinocytes through PTEN suppression: implications in skin carcinogenesis.

    PubMed

    Han, Weinong; Ming, Mei; He, Tong-Chuan; He, Yu-Ying

    2010-04-01

    Non-melanoma skin cancer, the most common neoplasia after solid organ transplantation, causes serious morbidity and mortality and is related to sun exposure. Cyclosporin A (CsA) has been used widely to prevent rejection in organ transplantation. The mechanism of CsA action in causing cancer was thought to be well understood via immunosuppression. Here, we show that CsA promotes primary skin tumor growth in immune-deficient mice and keratinocyte growth in vitro. In addition, CsA enhances keratinocyte survival from removal of extracellular matrix or UVB radiation. At the molecular level, CsA increases AKT activation after serum treatment and UVB irradiation. Furthermore we found that expression of PTEN, the negative regulator of AKT activation, is significantly reduced post-CsA in human HaCaT and A431 cells and in mouse skin in vivo. CsA-induced PTEN down-regulation occurs at the transcription level and is epidermal growth factor receptor-dependent. Such PTEN suppression is required for increased AKT activation. Inhibition of AKT activation abolishes CsA-promoted growth and survival, indicating that AKT hyperactivation is essential for both growth and survival of CsA-treated cells. In addition, mTOR signaling as a known AKT downstream pathway is required for CsA-enhanced growth and survival. Taken together, we have identified the PTEN/AKT pathway as new molecular targets of CsA in epidermal keratinocytes, suggesting a previously unknown mechanism in CsA-enhanced skin carcinogenesis. Our findings challenge assumptions about how CsA-associated tumors arise in skin. PMID:20154081

  1. Anti-epidermal growth factor receptor skin toxicity: a matter of topical hydration.

    PubMed

    Ferrari, Daris; Codecà, Carla; Bocci, Barbara; Crepaldi, Francesca; Violati, Martina; Viale, Giulia; Careri, Carmela; Caldiera, Sarah; Bordin, Veronica; Luciani, Andrea; Zonato, Sabrina; Cassinelli, Gabriela; Foa, Paolo

    2016-02-01

    Skin toxicity is a frequent complication of anti-epidermal growth factor receptor therapy, which can be an obstacle in maintaining the dose intensity and may negatively impact on the clinical outcome of cancer patients. Skin lesions depend on the disruption of the keratinocyte development pathways and no treatment is clearly effective in resolving the cutaneous alterations frequently found during anti-epidermal growth factor receptor therapy. Among systemic treatments, oral tetracycline proved to be useful in preventing skin manifestations. We describe the case of a patient affected by metastatic colorectal cancer, for whom a combination of chemotherapy and cetuximab was used as second-line treatment. The patient developed a symptomatic papulopustular skin rash that disappeared completely after a twice-daily application of a hydrating and moisturizing cream, mainly consisting of a mixture of paraffin, silicone compounds, and macrogol. The marked cutaneous amelioration allowed the patient to continue cetuximab without any further symptoms and was associated with a partial radiological response. PMID:26469836

  2. Reference genes for quantitative real time PCR in UVB irradiated keratinocytes.

    PubMed

    Balogh, Attila; Paragh, György; Juhász, Attila; Köbling, Tamás; Törocsik, Dániel; Mikó, Edit; Varga, Viktória; Emri, Gabriella; Horkay, Irén; Scholtz, Beáta; Remenyik, Eva

    2008-12-11

    Real time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) is a sensitive and highly reproducible method often used for determining mRNA levels. To enable proper comparison of gene expression genes expressed at stabile levels within the cells in the studied experimental system need to be identified and used as reference. Ultraviolet B (UVB) radiation is an exogenous carcinogenic stimulus in keratinocytes, and UVB elicited changes have extensively been studied by qRT-PCR, yet a comparison of commonly used reference genes in UVB treatment is lacking. To find the best genes for compensating slight inter-sample variations in keratinocytes in UVB experiments and to understand the potential effects of improper reference gene (RG) selection we have analyzed the mRNA expression of 10 housekeeping genes in neonatal human epidermal keratinocytes (NHEK) after UVB treatment. The biological effect of the used UVB light source was validated by trypane blue exclusion, MTT and comet assays. 20-40mJ/cm(2) dose was chosen for the experiments. The stability of the 10 RGs was assessed by the GeNorm and Normfinder software tools. Regardless of their slightly different algorithm the programs found succinate dehydrogenase complex subunit A (SDHA) to be the best individual RG and SDHA and phosphoglycerate kinase-1 (PGK1) as the most suitable combination. Analysis of the expression of tumor necrosis factor alpha (TNFalpha) and vascular endothelial growth factor (VEGF) found that while the perception of changes in TNF-alpha, a gene undergoing marked upregulation after UVB irradiation is independent of the used RG, changes seen in the more modestly upregulated VEGF are greatly effected by reference gene selection. These findings highlight the importance of reference gene selection in UVB irradiation experiments, and provide evidence that using SDHA or the combination of SDHA and PGK1 as standards could be a reliable method for normalizing qRT-PCR results in keratinocytes after UVB treatment. PMID:18789713

  3. Nutrients versus growth factors in mTORC1 activation

    E-print Network

    Efeyan, Alejo

    Growth factors and nutrients regulate the mTORC1 [mammalian (or mechanistic) target of rapamycin complex 1] by different mechanisms. The players that link growth factors and mTORC1 activation have been known for several ...

  4. The role of connective tissue growth factor in skeletal growth and development

    E-print Network

    The role of connective tissue growth factor in skeletal growth and development Reem A. Kanaan1 Gloucestershire Royal Hospital, U.K. Source of support: Self financing Summary Connective tissue growth factor-61, CTGF, NOV family; CTGF ­ connective tissue growth factor; Cyr61/CCN1 ­ cysteine-rich 61; NOV/CCN3

  5. Hematopoietic growth factors in acute leukemia.

    PubMed

    Rowe, J M; Liesveld, J L

    1997-03-01

    The hematopoietic growth factors are glycoproteins that can be produced by recombinant DNA technology. They have many potential clinical uses in acute leukemia; several areas have been explored extensively and much data are available from clinical trials. Other areas are of potential interest, but have a paucity of clinical information. The past decade has seen major strides in the development and clinical application of cytokines in acute leukemia and it is expected that this trend will continue over the next decade as further areas are explored and results of clinical trials mature to enable us to determine the precise role of cytokines in the clinical setting. PMID:9067570

  6. Growth factor in f(T) gravity

    SciTech Connect

    Zheng, Rui; Huang, Qing-Guo E-mail: huangqg@itp.ac.cn

    2011-03-01

    We derive the evolution equation of growth factor for the matter over-dense perturbation in f(T) gravity. For instance, we investigate its behavior in power law model at small redshift and compare it to the prediction of ?CDM and dark energy with the same equation of state in the framework of Einstein general relativity. We find that the perturbation in f(T) gravity grows slower than that in Einstein general relativity if ?f/?T > 0 due to the effectively weakened gravity.

  7. Growth factor in f(T) gravity

    E-print Network

    Rui Zheng; Qing-Guo Huang

    2011-02-23

    We derive the evolution equation of growth factor for the matter over-dense perturbation in $f(T)$ gravity. For instance, we investigate its behavior in power law model at small redshift and compare it to the prediction of $\\Lambda$CDM and dark energy with the same equation of state in the framework of Einstein general relativity. We find that the perturbation in $f(T)$ gravity grows slower than that in Einstein general relativity if $\\p f/\\p T>0$ due to the effectively weakened gravity.

  8. Decorin: A Growth Factor Antagonist for Tumor Growth Inhibition

    PubMed Central

    Järvinen, Tero A. H.; Prince, Stuart

    2015-01-01

    Decorin (DCN) is the best characterized member of the extracellular small leucine-rich proteoglycan family present in connective tissues, typically in association with or “decorating” collagen fibrils. It has substantial interest to clinical medicine owing to its antifibrotic, anti-inflammatory, and anticancer effects. Studies on DCN knockout mice have established that a lack of DCN is permissive for tumor development and it is regarded as a tumor suppressor gene. A reduced expression or a total disappearance of DCN has been reported to take place in various forms of human cancers during tumor progression. Furthermore, when used as a therapeutic molecule, DCN has been shown to inhibit tumor progression and metastases in experimental cancer models. DCN affects the biology of various types of cancer by targeting a number of crucial signaling molecules involved in cell growth, survival, metastasis, and angiogenesis. The active sites for the neutralization of different growth factors all reside in different parts of the DCN molecule. An emerging concept that multiple proteases, especially those produced by inflammatory cells, are capable of cleaving DCN suggests that native DCN could be inactivated in a number of pathological inflammatory conditions. In this paper, we review the role of DCN in cancer. PMID:26697491

  9. Decorin: A Growth Factor Antagonist for Tumor Growth Inhibition.

    PubMed

    Järvinen, Tero A H; Prince, Stuart

    2015-01-01

    Decorin (DCN) is the best characterized member of the extracellular small leucine-rich proteoglycan family present in connective tissues, typically in association with or "decorating" collagen fibrils. It has substantial interest to clinical medicine owing to its antifibrotic, anti-inflammatory, and anticancer effects. Studies on DCN knockout mice have established that a lack of DCN is permissive for tumor development and it is regarded as a tumor suppressor gene. A reduced expression or a total disappearance of DCN has been reported to take place in various forms of human cancers during tumor progression. Furthermore, when used as a therapeutic molecule, DCN has been shown to inhibit tumor progression and metastases in experimental cancer models. DCN affects the biology of various types of cancer by targeting a number of crucial signaling molecules involved in cell growth, survival, metastasis, and angiogenesis. The active sites for the neutralization of different growth factors all reside in different parts of the DCN molecule. An emerging concept that multiple proteases, especially those produced by inflammatory cells, are capable of cleaving DCN suggests that native DCN could be inactivated in a number of pathological inflammatory conditions. In this paper, we review the role of DCN in cancer. PMID:26697491

  10. A decorin-deficient matrix affects skin chondroitin/dermatan sulfate levels and keratinocyte function.

    PubMed

    Nikolovska, Katerina; Renke, Jana K; Jungmann, Oliver; Grobe, Kay; Iozzo, Renato V; Zamfir, Alina D; Seidler, Daniela G

    2014-04-01

    Decorin is a small leucine-rich proteoglycan harboring a single glycosaminoglycan chain, which, in skin, is mainly composed of dermatan sulfate (DS). Mutant mice with targeted disruption of the decorin gene (Dcn(-/-)) exhibit an abnormal collagen architecture in the dermis and reduced tensile strength, collectively leading to a skin fragility phenotype. Notably, Ehlers-Danlos patients with mutations in enzymes involved in the biosynthesis of DS display a similar phenotype, and recent studies indicate that DS is involved in growth factor binding and signaling. To determine the impact of the loss of DS-decorin in the dermis, we analyzed the glycosaminoglycan content of Dcn(-/-) and wild-type mouse skin. The total amount of chondroitin/dermatan sulfate (CS/DS) was increased in the Dcn(-/-) skin, but was overall less sulfated with a significant reduction in bisulfated ?DiS2,X (X=4 or 6) disaccharide units, due to the reduced expression of uronyl 2-O sulfotransferase (Ust). With increasing age, sulfation declined; however, Dcn(-/-) CS/DS was constantly undersulfated vis-à-vis wild-type. Functionally, we found altered fibroblast growth factor (Fgf)-7 and -2 binding due to changes in the micro-heterogeneity of skin Dcn(-/-) CS/DS. To better delineate the role of decorin, we used a 3D Dcn(-/-) fibroblast cell culture model. We found that the CS/DS extracts of wild-type and Dcn(-/-) fibroblasts were similar to the skin sugars, and this correlated with the lack of uronyl 2-O sulfotransferase in the Dcn(-/-) fibroblasts. Moreover, Ffg7 binding to total CS/DS was attenuated in the Dcn(-/-) samples. Surprisingly, wild-type CS/DS significantly reduced the binding of Fgf7 to keratinocytes in a concentration dependent manner unlike the Dcn(-/-) CS/DS that only affected the binding at higher concentrations. Although binding to cell-surfaces was quite similar at higher concentrations, keratinocyte proliferation was differentially affected. Higher concentration of Dcn(-/-) CS/DS induced proliferation in contrast to wild-type CS/DS. 3D co-cultures of fibroblasts and keratinocytes showed that, unlike Dcn(-/-) CS/DS, wild-type CS/DS promoted differentiation of keratinocytes. Collectively, our results provide novel mechanistic explanations for the reported defects in wound healing in Dcn(-/-) mice and possibly Ehlers-Danlos patients. Moreover, the lack of decorin-derived DS and an altered CS/DS composition differentially influence keratinocyte behavior. PMID:24447999

  11. The role of the tetraspanin CD151 in primary keratinocyte and fibroblast functions: Implications for wound healing

    SciTech Connect

    Geary, Sean M.; Cowin, Allison J.; Copeland, Ben; Baleato, Rosa M.; Miyazaki, Kaoru; Ashman, Leonie K.

    2008-07-01

    Previous studies showed that CD151-null mice have a skin wound healing deficit. To gain an understanding of the role of CD151 in re-epithelialisation and dermal contraction, keratinocyte and fibroblast functions were assayed. Primary CD151-null keratinocytes displayed defective migration on Matrigel (a basement membrane equivalent) and laminin-332, the primary adhesion component of basement membranes, but not on collagen-I. Adhesion, spreading and proliferation were also deficient on laminin-332, but not collagen-I. The data suggest that loss of CD151 impairs the function of its primary interaction partners, integrin {alpha}3{beta}1- and/or {alpha}6{beta}4 which bind to laminin-332. Skin fibroblasts also produce CD151 mRNA. CD151-null fibroblasts migrated significantly faster on collagen I than wild type fibroblasts, confirming that they possess functional collagen receptors. However, no significant decrease in the ability of CD151-null fibroblasts to cause contraction in floating collagen gel assays in response to transforming growth factor beta-1 (TGF-{beta}1) or platelet derived growth factor (PDGF-BB) was observed, nor was there an effect on fibroblast adhesion or proliferation on collagen-I. The data implicate CD151 as a facilitator of laminin-332-mediated keratinocyte functions that impact on the re-epithelialisation process intrinsic to wound healing and further suggest a potential novel role for CD151 in fibroblast migration.

  12. UVC modulation of epidermal growth factor receptor number in HeLa S3 cells.

    PubMed

    Ley, K D; Ellem, K A

    1992-02-01

    Induction of transforming growth factor alpha (TGF alpha) in human cell lines by 254 nm ultraviolet radiation (UVC) suggests that TGF alpha may have an autocrine role in UV-induced tumorigenesis. Binding of TGF alpha to epidermal growth factor receptor (EGFR) is an important initial step in transducing the signal for cell division. Experiments reported herein were designed to determine whether, in addition to inducing TGF alpha, UVC might also induce changes in the levels of EGFR on HeLa S3 cells [125I]EGF binding to HeLa S3 cells was inhibited 8 h after exposure to 7 J/m2 UVC radiation followed by increased [125I]EGF binding 16-32 h after irradiation. Scatchard analysis of EGF binding at 28 h indicated that irradiated cells had 60% more receptors with no differences in apparent binding affinities (56,300 +/- 5494 receptors versus 34,900 +/- 1899 receptors in sham-irradiated cells). Cell cycle analysis at 8 h post-UVC indicated that cells had slowed traverse of S-phase, but by 24 and 48 h, times at which increases in [125I]EGF were evident, cell cycle distributions were essentially back to normal. These results indicate that UVC modulates EGFR numbers in HeLa S3 cells and suggest that solar radiation may modulate EGFR numbers in keratinocytes or other cells in the skin. The presence of UV-induced growth factors such as TGF alpha and increased levels of EGFR may result in sustained cell proliferation by autocrine or paracrine mechanisms. These populations of cycling cells would then be at risk for subsequent mutational events that result in transformation to a tumorigenic state. PMID:1740007

  13. Insulin-Like Growth Factor and Epidermal Growth Factor Signaling in Breast Cancer Cell Growth: Focus on Endocrine Resistant Disease

    PubMed Central

    Voudouri, Kallirroi; Berdiaki, Aikaterini; Tzardi, Maria; Tzanakakis, George N.; Nikitovic, Dragana

    2015-01-01

    Breast cancer is the most common type of cancer for women worldwide with a lifetime risk amounting to a staggering total of 10%. It is well established that the endogenous synthesis of insulin-like growth factor (IGF) and epidermal growth factor (EGF) polypeptide growth factors are closely correlated to malignant transformation and all the steps of the breast cancer metastatic cascade. Numerous studies have demonstrated that both estrogens and growth factors stimulate the proliferation of steroid-dependent tumor cells, and that the interaction between these signaling pathways occurs at several levels. Importantly, the majority of breast cancer cases are estrogen receptor- (ER-) positive which have a more favorable prognosis and pattern of recurrence with endocrine therapy being the backbone of treatment. Unfortunately, the majority of patients progress to endocrine therapy resistant disease (acquired resistance) whereas a proportion of patients may fail to respond to initial therapy (de novo resistance). The IGF-I and EGF downstream signaling pathways are closely involved in the process of progression to therapy resistant disease. Modifications in the bioavailability of these growth factors contribute critically to disease progression. In the present review therefore, we will discuss in depth how IGF and EGF signaling participate in breast cancer pathogenesis and progression to endocrine resistant disease. PMID:26258011

  14. Neuropeptides as lung cancer growth factors.

    PubMed

    Moody, Terry W; Moreno, Paola; Jensen, Robert T

    2015-10-01

    This manuscript is written in honor of the Festschrift for Abba Kastin. I met Abba at a Society for Neuroscience meeting and learned that he was Editor-in-Chief of the Journal Peptides. I submitted manuscripts to the journal on "Neuropeptides as Growth Factors in Cancer" and subsequently was named to the Editorial Advisory Board. Over the past 30 years I have published dozens of manuscripts in Peptides and reviewed hundreds of submitted manuscripts. It was always rewarding to interact with Abba, a consummate professional. When I attended meetings in New Orleans I would sometimes go out to dinner with him at the restaurant "Commanders Palace". When I chaired the Summer Neuropeptide Conference we were honored to have him receive the Fleur Strand Award one year in Israel. I think that his biggest editorial contribution has been the "Handbook of Biologically Active Peptides." I served as a Section Editor on "Cancer/Anticancer Peptides" and again found that it was a pleasure working with him. This review focuses on the mechanisms by which bombesin-like peptides, neurotensin and vasoactive intestinal peptide regulate the growth of lung cancer. PMID:25836991

  15. 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

  16. Endorsement of Growth Factors in Experiential Training Groups

    ERIC Educational Resources Information Center

    Kiweewa, John; Gilbride, Dennis; Luke, Melissa; Seward, Derek

    2013-01-01

    The purpose of this study was to identify student growth factors during a semester long Master's level group counseling class. Results indicated that 12 growth factors accounted for 86% of the total number of critical incidents that participants reported as influencing their personal growth and awareness during the group experience. Two other…

  17. Design of Growth Factor Sequestering Biomaterials

    PubMed Central

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

    2014-01-01

    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

  18. Pigment-independent cAMP-mediated epidermal thickening protects against cutaneous UV injury by keratinocyte proliferation

    PubMed Central

    Scott, Timothy L.; Christian, P.A.; Kesler, M.; Donohue, Kevin M.; Shelton, Brent; Wakamatsu, Kazumasa; Ito, Shosuke; D’Orazio, John

    2012-01-01

    The epidermis increases pigmentation and epidermal thickness in response to ultraviolet exposure to protect against UV-associated carcinogenesis; however, the contribution of epidermal thickness has been debated. In a humanized skin mouse model that maintains interfollicular epidermal melanocytes, we found that forskolin, a small molecule that directly activates adenylyl cyclase and promotes cAMP generation, up-regulated epidermal eumelanin accumulation in fair-skinned melanocortin-1-receptor (Mc1r)-defective animals. Forskolin-induced pigmentation was associated with a reproducible expansion of epidermal thickness irrespective of melanization or the presence of epidermal melanocytes. Rather, forskolin-enhanced epidermal thickening was mediated through increased keratinocyte proliferation, indirectly through secreted factor(s) from cutaneous fibroblasts. We identified keratinocyte growth factor (Kgf) as a forskolin-induced fibroblast-derived cytokine that promoted keratinocyte proliferation, as forskolin induced Kgf expression both in the skin and in primary fibroblasts. Lastly, we found that even in the absence of pigmentation, forskolin-induced epidermal thickening significantly diminished the amount of UVA and UVB that passed through whole skin and reduced the amount of UVB-associated epidermal sunburn cells. These findings suggest the possibility of pharmacologic-induced epidermal thickening as a novel UV-protective therapeutic intervention, particularly for individuals with defects in pigmentation and adaptive melanization. PMID:23078399

  19. Pigment-independent cAMP-mediated epidermal thickening protects against cutaneous UV injury by keratinocyte proliferation.

    PubMed

    Scott, Timothy L; Christian, Perry A; Kesler, Melissa V; Donohue, Kevin M; Shelton, Brent; Wakamatsu, Kazumasa; Ito, Shosuke; D'Orazio, John

    2012-10-01

    The epidermis increases pigmentation and epidermal thickness in response to ultraviolet exposure to protect against UV-associated carcinogenesis; however, the contribution of epidermal thickness has been debated. In a humanized skin mouse model that maintains interfollicular epidermal melanocytes, we found that forskolin, a small molecule that directly activates adenylyl cyclase and promotes cAMP generation, up-regulated epidermal eumelanin accumulation in fair-skinned melanocortin-1-receptor (Mc1r)-defective animals. Forskolin-induced pigmentation was associated with a reproducible expansion of epidermal thickness irrespective of melanization or the presence of epidermal melanocytes. Rather, forskolin-enhanced epidermal thickening was mediated through increased keratinocyte proliferation, indirectly through secreted factor(s) from cutaneous fibroblasts. We identified keratinocyte growth factor (Kgf) as a forskolin-induced fibroblast-derived cytokine that promoted keratinocyte proliferation, as forskolin induced Kgf expression both in the skin and in primary fibroblasts. Lastly, we found that even in the absence of pigmentation, forskolin-induced epidermal thickening significantly diminished the amount of UV-A and UV-B that passed through whole skin and reduced the amount of UV-B-associated epidermal sunburn cells. These findings suggest the possibility of pharmacologic-induced epidermal thickening as a novel UV-protective therapeutic intervention, particularly for individuals with defects in pigmentation and adaptive melanization. PMID:23078399

  20. 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

  1. Growth factor responsiveness of human retinal pigment epithelial cells.

    PubMed

    Leschey, K H; Hackett, S F; Singer, J H; Campochiaro, P A

    1990-05-01

    Growth factor effects on DNA synthesis in density-arrested human retinal pigment epithelial cells were assessed by [3H]-thymidine incorporation. Acidic and basic fibroblast growth factor and epidermal growth factor were potent stimulators, whereas platelet-derived growth factor, insulinlike growth factor-1, and insulin were weak or modest stimulators when used alone. When used in combination, each of the above growth factors caused a significant enhancement of [3H]-thymidine incorporation regardless of its effect when used alone. The combination of all four growth factors was significantly more effective than all other combinations, demonstrating synergism in their action. Similar results were found in cell proliferation assays. In contrast to this, transforming growth factor-beta inhibited the ability of each of the other growth factors and serum-containing media to stimulate [3H]-thymidine incorporation. These data suggest that DNA synthesis in human retinal pigment epithelial cells can be modulated by several growth factors, some in a stimulatory or synergistic manner and at least one in an inhibitory manner. A better understanding of these complex interactions may provide insights relevant to normal and abnormal ocular wound healing. PMID:2186011

  2. Direct binding of hepatocyte growth factor and vascular endothelial growth factor to CD44v6.

    PubMed

    Volz, Yvonne; Koschut, David; Matzke-Ogi, Alexandra; Dietz, Marina S; Karathanasis, Christos; Richert, Ludovic; Wagner, Moritz G; Mély, Yves; Heilemann, Mike; Niemann, Hartmut H; Orian-Rousseau, Véronique

    2015-01-01

    CD44v6, a member of the CD44 family of transmembrane glycoproteins is a co-receptor for two receptor tyrosine kinases (RTKs), Met and VEGFR-2 (vascular endothelial growth factor receptor 2). CD44v6 is not only required for the activation of these RTKs but also for signalling. In order to understand the role of CD44v6 in Met and VEGFR-2 activation and signalling we tested whether CD44v6 binds to their ligands, HGF (hepatocyte growth factor) and VEGF (vascular endothelial growth factor), respectively. FACS analysis and cellular ELISA showed binding of HGF and VEGF only to cells expressing CD44v6. Direct binding of CD44v6 to HGF and VEGF was demonstrated in pull-down assays and the binding affinities were determined using MicroScale Thermophoresis, fluorescence correlation spectroscopy and fluorescence anisotropy. The binding affinity of CD44v6 to HGF is in the micromolar range in contrast with the high-affinity binding measured in the case of VEGF and CD44v6, which is in the nanomolar range. These data reveal a heparan sulfate-independent direct binding of CD44v6 to the ligands of Met and VEGFR-2 and suggest different roles of CD44v6 for these RTKs. PMID:26181364

  3. Transcriptional modulation of transin gene expression by epidermal growth factor and transforming growth factor beta

    SciTech Connect

    Machida, C.M.; Muldoon, L.L.; Rodland, K.D.; Magun, B.E.

    1988-06-01

    Transin is a transformation-associated gene which is expressed constitutively in rat fibroblasts transformed by a variety of oncogenes and in malignant mouse skin carcinomas but not benign papillomas or normal skin. It has been demonstrated that, in nontransformed Rat-1 cells, transin RNA expression is modulated positively by epidermal growth factor (EGF) and negatively by transforming growth factor beta (TGF-BETA); other peptide growth factors were found to have no effect on transin expression. Results presented here indicate that both protein synthesis and continuous occupancy of the EGF receptor by EGF were required for sustained induction of transin RNA. Treatment with TGF-BETA inhibited the ability of EGF to induce transin, whether assayed at the transcriptional level by nuclear run-on analysis or at the level of transin RNA accumulation by Northern (RNA) blot analysis of cellular RNA. TGF-BETA both blocked initial production of transin transcription by EGF and halted established production of transin transcripts during prolonged treatment. These results suggest that TGF-BETA acts at the transcriptional level to antagonize EGF-mediated induction of transin gene expression.

  4. Stability of faecal hepatocyte growth factor determination.

    PubMed

    Nayeri, F; Nilsson, I; Brudin, L; Almer, S

    2004-01-01

    In order to evaluate the accuracy and reproducibility of determination of hepatocyte growth factor (HGF) levels in faeces, the stability of HGF in samples processed in different ways was investigated. An ELISA method was used for determination of HGF concentrations. Faeces samples from healthy controls and patients with infectious diarrhoea were studied. It was found that faeces HGF concentration remained stable irrespective of whether samples were freeze-thawed several times, kept for 6, 12 or 24 h at room temperature or refrigerated for 6, 12, 24 or 36 h; the levels of HGF did not change significantly when samples were freeze-dried. Adding protease inhibitor to the faeces samples did not affect the HGF levels. There were no significant differences between HGF levels using phosphate buffered saline (PBS) (pH 7.4) or NaCL as buffer, but it was observed that levels of HGF were significantly lower in the samples that were diluted in distilled water. Although both HGF and albumin through various mechanisms may increase in faeces during infectious diarrhoea, there was no significant correlation between faeces HGF levels and albumin levels, which might indicate local production of HGF in the bowel in response to infection. It is concluded that determination of faeces HGF levels is feasible with a high degree of stability. Increased HGF levels in faeces might represent a local production of HGF during bowel injury and might be of use as a diagnostic and monitoring assay. PMID:15370465

  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. Nerve growth factor actions on the brain

    SciTech Connect

    Martinez, H.J.

    1989-01-01

    We examined the effect of the trophic protein, nerve growth factor (NGF), on cultures of fetal rat neostriatum and basal forebrain-medial septal area (BF-MS) to define its role in brain development. Treatment of cultures with NGF resulted in an increase in the specific activity of the cholinergic enzyme choline acetyltransferase (CAT) in both brain areas. CAT was immunocytochemically localized to neurons. In the BF-MS, NGF treatment elicited a marked increase in staining intensity and an apparent increase in the number of CAT-positive neurons. Moreover, treatment of BF-MS cultures with NGF increased the activity of acetylcholinesterase, suggesting that the cholinergic neuron as a whole was affected. To begin defining mechanisms of action of NGF in the BF-MS, we detected NGF receptors by two independent methods. Receptors were localized to two different cellular populations: neuron-like cells, and non-neuron-like cells. Dissociation studies with ({sup 125}I)NGF suggested that high affinity receptors were localized to the neuron-like population. Only low-affinity receptors were localized to the non-neuron-like cells. Moreover, employing combined immunocytochemistry and ({sup 125}I)NGF autoradiography, we detected a subpopulation of CAT-containing neutrons that exhibited high-affinity binding. Unexpectedly, a gamma-aminobutyric acid (GABA)-containing cell group also expressed high affinity binding. However, only subsets of cholinergic or GABA neurons expressed high-affinity biding, suggesting that these transmitter populations are composed of differentially response subpopulations.

  7. Hepatocyte growth factor measurement in AL amyloidosis.

    PubMed

    Abraham, Julie; Desport, Estelle; Rigaud, Charlotte; Marin, Benoit; Bender, Sébastien; Lacombe, Corinne; Moreau, Stéphane; Yagoubi, Fatima; Bordessoule, Dominique; Lavergne, David; Bridoux, Frank; Jaccard, Arnaud

    2015-01-01

    Hepatocyte growth factor (HGF) is a pro-angiogenic cytokine activated by tissue-type plasminogen activator (tPA) that might play a role in the progression of multiple myeloma (MM). Preliminary studies indicated that serum HGF levels were higher in patients with AL amyloidosis (AL) compared to those with MM. The aim of the present study was to determine whether HGF is a relevant marker of diagnosis and prognosis in AL. HGF serum levels were measured at diagnosis in patients with monoclonal gammopathy (MG) without AL (76 controls), or with biopsy-proven systemic AL (69 patients). HGF serum levels were significantly higher in patients with AL compared to controls, respectively, 11.2?ng/mL [min: 0.95-max: 200.4] versus 1.4?ng/mL [min: 0.82-max: 6.2] (p?

  8. Novel Drosophila receptor that binds multiple growth factors

    SciTech Connect

    Rosner, M.R.; Thompson, K.L.; Garcia, V.; Decker, S.J.

    1986-05-01

    The authors have recently reported the identification of a novel growth factor receptor from Drosophila cell cultures that has dual binding specificity for both insulin and epidermal growth factor (EGF). This 100 kDa protein is also antigenically related to the cytoplasmic region of the mammalian EGF receptor-tyrosine kinase. They now report that this protein binds to mammalian nerve growth factor and human transforming growth factor alpha as well as insulin and EGF with apparent dissociation constants ranging from 10/sup -6/ to 10/sup -8/ M. The 100 kDa protein can be affinity-labeled with these /sup 125/I-labeled growth factors after immunoprecipitation with anti-EGF receptor antiserum. These four growth factors appear to share a common binding site, as evidenced by their ability to block affinity labelling by /sup 125/I-insulin. No significant binding to the 100 kDa protein was observed with platelet-derived growth factor, transforming growth factor beta, or glucagon. The 100 kDa Drosophila protein has a unique ligand-binding spectrum with no direct counterpart in mammalian cells and may represent an evolutionary precursor of the mammalian receptors for these growth factors.

  9. Glycosaminoglycan-protein interactions : the fibroblast growth factor paradigm

    E-print Network

    Kwan, Chi-Pong, 1973-

    2002-01-01

    Specific interactions between heparan sulfate glycosaminoglycans (HSGAGs) and proteins are central to a wide range of biological processes such as anticoagulation, angiogenesis and growth factor activation. The specificity ...

  10. 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.

  11. Characterization of transforming growth factor beta superfamily, growth factors, transcriptional factors, and lipopolysaccharide in bovine cystic ovarian follicles.

    PubMed

    Polat, I M; Alçi?ir, E; Pekcan, M; Vural, S A; Özenç, E; Canatan, H E; Küplülü, ?; Dal, G E; Yazlik, M O; Baklaci, C; Vural, M R

    2015-10-01

    The process of transformation of growing bovine follicles into cysts is still a mystery. Local expression of proteins or factors, including transforming growth factor ?, growth factors, and transcription factors, plays a central role in mammals. Therefore, in abattoir-derived cystic ovarian follicles and follicular fluid, the role of some transforming growth factor ? superfamily proteins, insulinlike growth factor-1 (IGF-1) and GATA-4 and GATA-6, were investigated. The relationship between intrafollicular lipopolysaccharide (LPS) and etiopathogenesis of ovarian cysts was also assessed. Data on the preovulatory follicle and the largest follicle (F1) were compared. The number of intrafollicular LPS-positive samples and LPS concentrations were higher in cysts. Immunohistochemical staining was mildly positive for IGF-1, inhibin alpha, and GATA-4 in thecal cells. Staining for anti-Müllerian hormone (AMH), growth differentiation factor-9, bone morphogenetic protein-6 (BMP-6), and GATA-6 was insufficient for their quantitation, and oocytes could not be stained for any of the proteins tested in the cystic follicles. Expression of BMP-6, inhibin alpha, and IGF-1 was moderately higher in granulosa cells of F1 follicles, and all the proteins were moderately expressed in granulosa cells in preovulatory follicles. However, loss of GATA-6 staining was significant in F1 follicles. Intrafollicular progesterone, IGF-1, and AMH concentrations in cysts and F1 follicles were significantly higher than those in preovulatory follicles. Western blot analyses revealed that follicular fluid inhibin-? was strongly expressed, whereas expression of growth differentiation factor-9, BMP-6, GATA-4 and GATA-6 was lower in cysts than in preovulatory follicles. Also, high intrafollicular AMH concentration and low BMP-6 expression were closely associated with cystic degeneration and atresia. In conclusion, immunohistochemical loss of BMP-6 and GATA-6 in the granulosa cells together with high intrafollicular LPS levels may play important roles in disruption of the ovulatory mechanism and steroidogenic reactions in type 2 cyst. Also, high intrafollicular AMH concentration along with low BMP-6 expression may be used as indicators of the bovine degenarative ovarian follicles. PMID:26166168

  12. S100A8/A9 Stimulates Keratinocyte Proliferation in the Development of Squamous Cell Carcinoma of the Skin via the Receptor for Advanced Glycation-End Products

    PubMed Central

    Iotzova-Weiss, Guergana; Dziunycz, Piotr J.; Freiberger, Sandra N.; Läuchli, Severin; Hafner, Jürg; Vogl, Thomas; French, Lars E.; Hofbauer, Günther F. L.

    2015-01-01

    Squamous cell carcinoma (SCC) is the most common neoplasm in organ transplant recipients (OTR) on long-term immunosuppression and occurs 60- to 100-fold more frequently than in the general population. Here, we present the receptor for advanced glycation end products (RAGE) and S100A8/A9 as important factors driving normal and tumor keratinocyte proliferation. RAGE and S100A8/A9 were transcriptionally upregulated in SCC compared to normal epidermis, as well as in OTR compared to immunocompetent patients (IC) with SCC. The proliferation of normal and SCC keratinocytes was induced by exposure to exogenous S100A8/A9 which in turn was abolished by blocking of RAGE. The migratory activities of normal and SCC keratinocytes were also increased upon exposure to S100A8/A9. We demonstrated that exogenous S100A8/A9 induces phosphorylation of p38 and SAPK/JNK followed by activation of ERK1/2. We hypothesize that RAGE and S100A8/A9 contribute to the development of human SCC by modulating keratinocyte growth and migration. These processes do not seem to be impaired by profound drug-mediated immunosuppression in OTR. PMID:25811984

  13. Surface molecules on HaCaT keratinocytes after interaction with non-thermal atmospheric pressure plasma.

    PubMed

    Haertel, Beate; Hähnel, Marcel; Blackert, Susanne; Wende, Kristian; von Woedtke, Thomas; Lindequist, Ulrike

    2012-01-01

    Non-thermal atmospheric-pressure plasmas have been developed that will be used in future for several purposes, e.g. medicine. Living tissues and cells are at the focus of plasma treatment, e.g. to improve wound healing, or induce apoptosis and growth arrest in tumour cells. Detailed investigations of plasma-cell interactions are needed. Cell surface adhesion molecules as integrins, cadherins or the EGFR (epidermal growth factor receptor) are of importance in wound healing and also for development of cancer metastasis. This study has focused on measurement of cell surface molecules on human HaCaT keratinocytes (human adult low calcium temperature keratinocytes) promoting adhesion, migration and proliferation as one important feature of plasma-cell interactions. HaCaT keratinocytes were treated with plasma by a surface dielectric barrier discharge in air. Cell surface molecules and induction of intracellular ROS (reactive oxygen species) were analysed by flow cytometry 24 h after plasma treatment. Besides a reduction of cell viability a significant down-regulation of E-cadherin and the EGFR expression occurred. The influence on ?2- and ?1-integrins was less pronounced, and expression of ICAM-1 (intercellular adhesion molecule 1) was unaffected. The extent of effects depended on the exposure time of cells to the plasma and the treatment regimen. Intracellular level of ROS detected by the fluorescent dye H2DCFDA (2',7'-dichlorodihydrofluorescein diacetate) increased by plasma treatment, but it was neither dependent on the treatment time nor related to the different treatment regimens. Two-dimensional cultures of HaCaT keratinocytes appear to be a suitable method of investigating plasma-cell interactions. PMID:22973947

  14. Mechanism of Macrophage-Derived Chemokine/CCL22 Production by HaCaT Keratinocytes

    PubMed Central

    Yano, Chizuko; Komine, Mayumi; Kagami, Shinji; Tsunemi, Yuichiro; Ohtsuki, Mamitaro; Nakagawa, Hidemi

    2015-01-01

    Background CC chemokine ligand 17 (CCL17) and CCL22 are the functional ligands for CCR4. We previously reported that inhibitors of nuclear factor-kappa B and p38 mitogen-activated protein kinase (p38 MAPK), but not of extracellular signal-related kinase (ERK), inhibited tumor necrosis factor (TNF)-?- and interferon (IFN)-?-induced production of CCL17 by the human keratinocyte cell line, HaCaT. Further, an inhibitor of epidermal growth factor receptor (EGFR) enhanced the CCL17 production by these keratinocytes. Objective To identify the mechanism underlying CCL22 production by HaCaT cells. Methods We investigated the signal transduction pathways by which TNF-? and IFN-? stimulate HaCaT cells to produce CCL22 by adding various inhibitors. Results TNF-?- and IFN-?-induced CCL22 production was inhibited by PD98059, PD153035, Bay 11-7085, SB202190, c-Jun N-terminal kinase (JNK) inhibitor II, and Janus kinase (JAK) inhibitor 1. Conclusion Our results indicate that CCL22 production in HaCaT cells is dependent on ERK, EGFR, p38 MAPK, JNK, and JAK and is mediated by different signal pathways from those regulating CCL17 production. Altogether, our previous and present results suggest that EGFR activation represses CCL17 but enhances CCL22 production by these cells. PMID:25834353

  15. Non-thermal plasma activates human keratinocytes by stimulation of antioxidant and phase II pathways.

    PubMed

    Schmidt, Anke; Dietrich, Stephan; Steuer, Anna; Weltmann, Klaus-Dieter; von Woedtke, Thomas; Masur, Kai; Wende, Kristian

    2015-03-13

    Non-thermal atmospheric pressure plasma provides a novel therapeutic opportunity to control redox-based processes, e.g. wound healing, cancer, and inflammatory diseases. By spatial and time-resolved delivery of reactive oxygen and nitrogen species, it allows stimulation or inhibition of cellular processes in biological systems. Our data show that both gene and protein expression is highly affected by non-thermal plasma. Nuclear factor erythroid-related factor 2 (NRF2) and phase II enzyme pathway components were found to act as key controllers orchestrating the cellular response in keratinocytes. Additionally, glutathione metabolism, which is a marker for NRF2-related signaling events, was affected. Among the most robustly increased genes and proteins, heme oxygenase 1, NADPH-quinone oxidoreductase 1, and growth factors were found. The roles of NRF2 targets, investigated by siRNA silencing, revealed that NRF2 acts as an important switch for sensing oxidative stress events. Moreover, the influence of non-thermal plasma on the NRF2 pathway prepares cells against exogenic noxae and increases their resilience against oxidative species. Via paracrine mechanisms, distant cells benefit from cell-cell communication. The finding that non-thermal plasma triggers hormesis-like processes in keratinocytes facilitates the understanding of plasma-tissue interaction and its clinical application. PMID:25589789

  16. 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.

  17. Nerve growth factor-mediated vascular endothelial growth factor expression of astrocyte in retinal vascular development.

    PubMed

    Kim, You Sun; Jo, Dong Hyun; Lee, Hanjae; Kim, Jin Hyoung; Kim, Kyu-Won; Kim, Jeong Hun

    2013-02-22

    The angiogenic aspect of neurotrophins and their receptors rather than the neuroscientific aspect has been focused. However, their role in retinal vascular development is underdiscovered. The purpose of this study is to understand the role of neurotrophin receptors in retinal vascular development and the mechanisms of their action. To identify the expression of tropomyosin receptor kinase receptor (Trk) in developing retina, tissues of 4, 8, 12, 16 and 26 day-old mice were prepared for experiments. Immunohistochemistry and immunofluorescence double staining against glial fibrillary acidic protein and type IV collagen were performed. TrkA was expressed mainly along the vessel structure in inner part of retina, especially in retinal astrocyte. In cultured primary astrocyte, recombinant nerve growth factor (NGF) was used to activate TrkA. NGF induced the phosphorylation of TrkA, and it also enhanced the level of activated Akt and vascular endothelial growth factor (VEGF) mRNA. Inhibition of phosphoinositide 3-kinase (PI3K) reversed the NGF-induced activation of these two molecules. This study demonstrated that TrkA activation on NGF leads to VEGF elevation by PI3K-Akt pathway and therefore suggested that TrkA could be a stimulator of retinal vascular development. PMID:23337506

  18. Targeting the opioid growth factor: opioid growth factor receptor axis for treatment of human ovarian cancer.

    PubMed

    Zagon, Ian S; Donahue, Renee; McLaughlin, Patricia J

    2013-05-01

    The opioid growth factor (OGF) - opioid growth factor receptor (OGFr) axis is a biological pathway that is present in human ovarian cancer cells and tissues. OGF, chemically termed [Met(5)]-enkephalin, is an endogenous opioid peptide that interfaces with OGFr to delay cells moving through the cell cycle by upregulation of cyclin-dependent inhibitory kinase pathways. OGF inhibitory activity is dose dependent, receptor mediated, reversible, protein and RNA dependent, but not related to apoptosis or necrosis. The OGF-OGFr axis can be targeted for treatment of human ovarian cancer by (i) administration of exogenous OGF, (ii) genetic manipulation to over-express OGFr and (iii) use of low dosages of naltrexone, an opioid antagonist, which stimulates production of OGF and OGFr for subsequent interaction following blockade of the receptor. The OGF-OGFr axis may be a feasible target for treatment of cancer of the ovary (i) in a prophylactic fashion, (ii) following cytoreduction or (iii) in conjunction with standard chemotherapy for additive effectiveness. In summary, preclinical data support the transition of these novel therapies for treatment of human ovarian cancer from the bench to bedside to provide additional targets for treatment of this devastating disease. PMID:23856908

  19. 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 ...

  20. The antipsoriatic agent monomethylfumarate has antiproliferative, prodifferentiative, and anti-inflammatory effects on keratinocytes.

    PubMed

    Helwa, Inas; Patel, Ravi; Karempelis, Peter; Kaddour-Djebbar, Ismail; Choudhary, Vivek; Bollag, Wendy B

    2015-01-01

    Monomethylfumarate (MMF) is thought to be the bioactive ingredient of the drug Fumaderm (Biogen Idec, Cambridge, MA), licensed in Germany since 1994 for the treatment of moderate-to-severe psoriasis. Psoriasis is a common inflammatory hyperproliferative skin disorder that involves cross-talk between different cell types, including immune cells and keratinocytes. Psoriatic lesions are characterized by hyperproliferation, aberrant differentiation, and inflammation, with the psoriatic cytokine network maintained by communication between immune cells and keratinocytes. Recently, there is increasing evidence regarding the pivotal role of keratinocytes in mediating the disease process, and these cells can be regarded as safe therapeutic targets. From the data available on human subjects treated with Fumaderm, MMF is an effective antipsoriatic agent with known effects on immune cells. However, little is known about its direct effects on keratinocytes. We hypothesized that MMF has direct antiproliferative, prodifferentiative, and anti-inflammatory effects on keratinocytes. Indeed, MMF dose-dependently inhibited [(3)H]thymidine incorporation into DNA, indicating a direct antiproliferative action on keratinocytes. MMF significantly increased the protein level of keratin 10, the early keratinocyte differentiation marker, and the activity of transglutaminase, a late differentiation marker. These results are consistent with an ability of MMF to promote keratinocyte differentiation and inhibit proliferation, thereby improving psoriatic lesions. In 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced keratinocytes, MMF significantly inhibited the expression of the proinflammatory cytokines, tumor necrosis factor-? (TNF?), interleukin-6, and interleukin-1? as well as the production of TNF?. Our results support the notion that MMF has direct antiproliferative, prodifferentiative, and anti-inflammatory effects on keratinocytes, highlighting its potential use as a multifactorial antipsoriatic agent. PMID:25332455

  1. Reduced growth factor requirement of keloid-derived fibroblasts may account for tumor growth

    SciTech Connect

    Russell, S.B.; Trupin, K.M.; Rodriguez-Eaton, S.; Russell, J.D.; Trupin, J.S.

    1988-01-01

    Keloids are benign dermal tumors that form during an abnormal wound-healing process is genetically susceptible individuals. Although growth of normal and keloid cells did not differ in medium containing 10% (vol/vol) fetal bovine serum, keloid culture grew to significantly higher densities than normal cells in medium containing 5% (vol/vol) fetal bovine serum, keloid cultures grew to significantly higher densities than normal cells in medium containing 5% (vol/vol) plasma or 1% fetal bovine serum. Conditioned medium from keloid cultures did not stimulate growth of normal cells in plasma nor did it contain detectable platelet-derived growth factor or epidermal growth factor. Keloid fibroblasts responded differently than normal adult fibroblasts to transforming growth factor ..beta... Whereas transforming growth factor ..beta.. reduced growth stimulation by epidermal growth factor in cells from normal adult skin or scars, it enhanced the activity of epidermal growth factor in cells from normal adult skin or scars, it enhanced the activity of epidermal growth factor in cells from keloids. Normal and keloid fibroblasts also responded differently to hydrocortisone: growth was stimulated in normal adult cells and unaffected or inhibited in keloid cells. Fetal fibroblasts resembled keloid cells in their ability to grow in plasma and in their response to hydrocortisone. The ability of keloid fibroblasts to grow to higher cell densities in low-serum medium than cells from normal adult skin or from normal early or mature scars suggests that a reduced dependence on serum growth factors may account for their prolonged growth in vivo. Similarities between keloid and fetal cells suggest that keloids may result from the untimely expression of growth-control mechanism that is developmentally regulated.

  2. 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.

  3. 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

  4. Material factors influencing metallic whisker growth

    NASA Astrophysics Data System (ADS)

    Rodekohr, Chad L.

    Whiskering refers to the formation of slender, long, metallic filaments, much thinner than a human hair, that grow on a metallic thin film surface. They are readily observed for pure and alloyed zinc (Zn), silver (Ag), cadmium (Cd), indium (In), and tin (Sn) surfaces. The longest reported whisker length is 4.5 mm long but most high-aspect ratio whiskers range from 1-500 mum. The focus of this research is upon Sn whiskers. Sn whiskers pose serious reliability problems for the electronics industry and are known to be the source of failure in a wide range of electronic devices, such as nuclear power facilities, heart pacemakers, commercial satellites, aviation radar, telecommunication equipment, and desktop computers. The problem with whiskering has been recently exacerbated by the worldwide shift to lead (Pb) free electronics and the continuing reduction in electrical contact pitches. A thorough understanding of the growth mechanism of Sn whiskers is urgently needed. Currently, there is no universally accepted model that explains the broad range of observations on whiskering. The goals of this research are: (1) to develop a more detailed understanding of the physical mechanisms leading to the initiation and growth of Sn whiskers and (2) to outline reasonable mitigation strategies that could be followed to reduce or eliminate the problem of Sn whiskers. The major contributions of this work are: (1) A reliable method for growing Sn whiskers with predictable incubation times has been developed and tested. (2) A surface oxide is not necessary for whisker growth. (3) Intermetallic compounds (IMC) are not necessary for whisker growth. (4) Smoother, not rougher, substrate surfaces promote whisker growth. (5) Whiskers grow under both compressive and tensile thin film stress states. (6) Whisker growth increases with externally applied compression and tension forces. (7) Sn whiskers are composed of pure Sn except for the expected thin, native Sn oxide on their surface. (8) For Sn on brass, the atom feedstock for whiskers lies within the film exclusively; the brass substrate does not contribute to whisker production. (9) The volume of film consumed by a metallic whisker is a simple volumetric calculation. (10) There are likely to be multiple mechanisms of whisker growth depending on the substrate - thin film system. (11) In general, the thickness of a metallic film does not have an effect on whisker growth qualities.

  5. 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

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

    PubMed

    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

    2014-04-01

    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

  7. Dual chain synthetic heparin-binding growth factor analogs

    DOEpatents

    Zamora, Paul O. (Gaithersburg, MD); Pena, Louis A. (Poquott, NY); Lin, Xinhua (Plainview, NY)

    2009-10-06

    The invention provides synthetic heparin-binding growth factor analogs having two peptide chains each branched from a branch moiety, such as trifunctional amino acid residues, the branch moieties separated by a first linker of from 3 to about 20 backbone atoms, which peptide chains bind a heparin-binding growth factor receptor and are covalently bound to a non-signaling peptide that includes a heparin-binding domain, preferably by a second linker, which may be a hydrophobic second linker. The synthetic heparin-binding growth factor analogs are useful as pharmaceutical agents, soluble biologics or as surface coatings for medical devices.

  8. Dual chain synthetic heparin-binding growth factor analogs

    DOEpatents

    Zamora, Paul O. (Gaithersburg, MD); Pena, Louis A. (Poquott, NY); Lin, Xinhua (Plainview, NY)

    2012-04-24

    The invention provides synthetic heparin-binding growth factor analogs having two peptide chains each branched from a branch moiety, such as trifunctional amino acid residues, the branch moieties separated by a first linker of from 3 to about 20 backbone atoms, which peptide chains bind a heparin-binding growth factor receptor and are covalently bound to a non-signaling peptide that includes a heparin-binding domain, preferably by a second linker, which may be a hydrophobic second linker. The synthetic heparin-binding growth factor analogs are useful as pharmaceutical agents, soluble biologics or as surface coatings for medical devices.

  9. 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

  10. EDUCATION AS A FACTOR IN ECONOMIC GROWTH.

    ERIC Educational Resources Information Center

    MACKERTICH, ALEX

    THE VALUE OF AN EDUCATION IN THE ECONOMIC GROWTH OF AN UNDERDEVELOPED COUNTRY (INDIA) WAS INVESTIGATED USING THE CASE STUDY APPROACH. DATA WERE GATHERED AT BOTH THE CENTRAL GOVERNMENT AND VILLAGE LEVELS THROUGH INTERVIEWS WITH INDIAN GOVERNMENT OFFICIALS AND FROM OFFICIAL GOVERNMENT PUBLICATIONS CONCERNING THE NATION'S EDUCATIONAL EFFORTS, AS…

  11. Phenylpropanoic Acid: Growth Factor for Ruminococcus albus

    PubMed Central

    Hungate, R. E.; Stack, Robert J.

    1982-01-01

    Phenylpropanoic acid accounted for part of the stimulatory effect of rumen fluid on the rate of growth and of cellulose digestion by cultures of Ruminococcus albus strain 8 grown on a chemically defined medium. As little as 3 ?M concentration gave maximum response. PMID:16346069

  12. Regulative and adaptive factors in craniofacial growth.

    PubMed

    Schumacher, G H

    1999-01-01

    Generally speaking, the animal experimental models described here are of theoretical importance. They fall naturally into the area of formulating general trends. Following elucidation of a series of concerns in the future, theoretical growth research will be able to provide more directly clinically applicable tools. Since no experimental animals of the masticatory type analogous to humans exist, results from animal experiments should be considered as statements on the biological reactions of analogous biological systems. Last but not least, biomechanical model representations point to the growth controlling functions of the bony and muscular head system components. These may provide an example for the analysis of degenerative changes in other parts of the body and serve as a theoretical basis for targeted therapeutic measures. PMID:10081551

  13. 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. ...

  14. Tunable dual growth factor delivery from polyelectrolyte multilayer films

    E-print Network

    Shah, Nisarg J.

    A promising strategy to accelerate joint implant integration and reduce recovery time and failure rates is to deliver a combination of certain growth factors to the integration site. There is a need to control the quantity ...

  15. Characterizing and engineering antibodies against the epidermal growth factor receptor

    E-print Network

    Chao, Ginger

    2008-01-01

    Epidermal growth factor receptor (EGFR) signaling leads to cellular proliferation and migration, and thus EGFR dysregulation can significantly contribute to the survival of tumor cells. Aberrant EGFR signaling due to ...

  16. Multiple signaling pathways are responsible for prostaglandin E2-induced murine keratinocyte proliferation

    PubMed Central

    Ansari, Kausar M.; Rundhaug, Joyce E.; Fischer, Susan M.

    2008-01-01

    Although prostaglandin E2 (PGE2) has been shown by pharmacological and genetic studies to be important in skin cancer, the molecular mechanism(s) by which it contributes to tumor growth is not well understood. In this study we investigated the mechanisms by which PGE2 stimulates murine keratinocyte proliferation using in vitro and in vivo models. In primary mouse keratinocyte (PMK) cultures, PGE2 activated the epidermal growth factor receptor (EGFR) and its downstream signaling pathways as well as increased cyclic AMP (cAMP) production and activated the cAMP response element binding protein (CREB). EGFR activation was not significantly inhibited by pretreatment with a c-src inhibitor (PP2), nor by a protein kinase A inhibitor (H-89). However, PGE2-stimulated extracellularly-regulated kinase1/2 (ERK1/2) activation was completely blocked by EGFR, ERK1/2 and phosphatidylinositol 3-kinase (PI3-K) pathway inhibitors. In addition, these inhibitors attenuated the PGE2-induced proliferation, nuclear factor-?B (NF-?B), activator protein-1 (AP-1) and CREB binding to the promoter regions of the cyclin D1 and vascular endothelial growth factor (VEGF) genes and expression of cyclin D1 and VEGF in PMKs. Similarly, in vivo, we found that wild type (WT) mice treated with PGE2 and untreated COX-2 overexpressing transgenic mice had higher levels of cell proliferation and expression of cyclin D1 and VEGF, as well as higher levels of activated EGFR, NF-?B, AP-1 and CREB, than vehicle-treated WT mice. Our findings provide evidence for a link between COX-2 overexpression and EGFR-, ERK-, PI3-K-, cAMP-mediated cell proliferation, and the tumor promoting activity of PGE2 in mouse skin. PMID:18567804

  17. Sputa nerve growth factor forms a preferable substitute to mouse 7S-? nerve growth factor

    PubMed Central

    2004-01-01

    The NGF (nerve growth factor) from Naja sputatrix has been purified by gel filtration followed by reversed-phase HPLC. The protein showed a very high ability to induce neurite formation in PC12 cells relative to the mouse NGF. Two cDNAs encoding isoforms of NGF have been cloned and an active recombinant NGF, sputa NGF, has been produced in Escherichia coli as a His-tagged fusion protein. Sputa NGF has been found to be non-toxic under both in vivo and in vitro conditions. The induction of neurite outgrowth by this NGF has been found to involve the high-affinity trkA–p75NTR complex of receptors. The pro-survival mechanism of p75NTR has been mediated by the activation of nuclear factor ?B gene by a corresponding down-regulation of inhibitory ?B gene. Real-time PCR and protein profiling (by surface-enhanced laser-desorption–ionization time-of-flight) have confirmed that sputa NGF up-regulates the expression of the endogenous NGF in PC12 cells. Preliminary microarray analysis has also shown that sputa NGF is capable of promoting additional beneficial effects such as the up-regulation of arginine vasopressin receptor 1A, voltage-dependent T-type calcium channel. Hence, sputa NGF forms a new and useful NGF. PMID:15225125

  18. Vitiligo patient-derived keratinocytes exhibit characteristics of normal wound healing via epithelial to mesenchymal transition.

    PubMed

    Banerjee, Poulomi; Venkatachalam, Sandhyaa; Mamidi, Murali Krishna; Bhonde, Ramesh; Shankar, Krupa; Pal, Rajarshi

    2015-05-01

    Vitiligo is an autoimmune disorder that leads to depigmentation of skin via melanocyte dysfunction. Keratinocyte-induced toxicity is one among the several etiological factors implicated for vitiligo, and hence, autologous keratinocyte grafting is projected as one of the primary mode of treatment for vitiligo. However, reports indicate that perilesional keratinocytes not only display signatures of apoptosis but also could secrete cytokines and mediators which have antagonistic effect on proliferation or survival. Therefore, we investigated how vitiligo patients' derived keratinocytes respond to surplus amounts of inflammatory cytokines and whether they recapitulate events that take place during conventional wound healing. The primary objective of our study was to determine whether keratinocytes isolated from a vitiligo patient would undergo epithelial-mesenchymal transition similar to their normal counterparts upon induction with inflammatory cytokines such as TGF-b1 and EGF. We found that these keratinocytes undergo EMT during wound repair accompanied with increase in the levels of mesenchymal markers and ECM proteins; decrease in the levels of epithelial markers and enhanced migratory ability. Besides, we also demonstrated that EMT induction leads to activation of SMAD and MAPK pathways via Ras, Raf, PAI 1, Snail, Slug and ZO1. To our knowledge, this is the first report on the characterization of primary keratinocytes isolated from vitiligo patients with respect to their wound healing capacity. PMID:25690925

  19. CRITICAL FACTORS CONTROLLING VEGETATION GROWTH ON COMPLETED SANITARY LANDFILLS

    EPA Science Inventory

    This study identifies some of the critical factors that affect tree and shrub growth on reclaimed sanitary landfill sites and determines which woody species are adaptable to the adverse growth conditions of such sites. Trees planted at the Edgeboro Landfill, East Brunswick, New J...

  20. Modelling hematopoiesis mediated by growth factors: Delay equations describing periodic

    E-print Network

    Crauste, Fabien

    and reg- ulation of blood cells. It is based upon differentiation of stem cells under the action of growth diseases, characterized by oscillations in circulating blood cells. A system of three differential between blood cells and growth factors. This stresses the localization of periodic hematological diseases

  1. Dental metal-induced innate reactivity in keratinocytes.

    PubMed

    Rachmawati, Dessy; Buskermolen, Jeroen K; Scheper, Rik J; Gibbs, Susan; von Blomberg, B Mary E; van Hoogstraten, Ingrid M W

    2015-12-25

    Gold, nickel, copper and mercury, i.e. four metals frequently used in dental applications, were explored for their capacity to induce innate immune activation in keratinocytes (KC). Due to their anatomical location the latter epithelial cells are key in primary local irritative responses of skin and mucosa. Fresh foreskin-derived keratinocytes and skin and gingiva KC cell lines were studied for IL-8 release as a most sensitive parameter for NF-kB activation. First, we verified that viral-defense mediating TLR3 is a key innate immune receptor in both skin- and mucosa derived keratinocytes. Second, we found that, in line with our earlier finding that ionized gold can mimic viral dsRNA in triggering TLR3, gold is very effective in KC activation. It would appear that epithelial TLR3 can play a key role in both skin- and mucosa localized irritation reactivities to gold. Subsequently we found that not only gold, but also nickel, copper and mercury salts can activate innate immune reactivity in keratinocytes, although the pathways involved remain unclear. Although current alloys have been optimized for minimal leakage of metal ions, secondary factors such as mechanical friction and acidity may still facilitate such leakage. Subsequently, these metal ions may create local irritation, itching and swelling by triggering innate immune reactions, potentially also facilitating the development of metal specific adaptive immunity. PMID:26456670

  2. Comparison of daunomycin effects on human keratinocytes and melanoma HTB 1410 cells. Image cytometry study.

    PubMed

    Drukala, Justyna; Rajwa, Bartlomiej; Pietrzkowski, Zbigniew; Korohoda, Wlodzimierz

    2003-01-01

    Interacting melanocytes and keratinocytes in the epidermis create a unique structure in which keratinocytes regulate the growth of melanocytes and the expression of cell surface molecules. The critical role of communication between these cells means that any anti-melanoma drug should be studied in the context of its possible influence on keratinocytes. For that reason, this study focused on comparing the influence of daunomycin on human melanoma cells and on keratinocytes in vitro. The effects were studied by cytochemical methods (TUNEL, FITC-Annexin V labelling, endocytosis activity assay, measurements of DNA content) and morphological methods (measurements of cell surface area, perimeter, extension, dispersion and elongation) to verify the hypothesis of differential response. The results of our research demonstrate that keratinocytes are less susceptible than melanoma cells to daunomycin treatment in vitro. Keratinocytes are also able to resume growth when the drug is removed from the medium, whereas melanoma cells have not demonstrated this capacity. Apoptosis was identified as the mechanism by which the drug exerts its cytostatic effects. PMID:12680242

  3. 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

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

    PubMed

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

    2013-03-01

    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 endothelin-1 (EDN1) in murine epidermis (EDN1(ep-/-) ) 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 ultraviolet B (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 EDN1(ep-/-) mice. Altogether, the present studies establish an essential role of EDN1 in epidermal keratinocytes to mediate UV-induced melanocyte homeostasis in vivo. PMID:23279852

  5. Fibroblast growth factor receptor 1 is principally responsible for fibroblast growth factor 2-induced catabolic activities in human articular chondrocytes

    E-print Network

    Yan, Dongyao; Chen, Di; Cool, Simon M.; van Wijnen, Andre J.; Mikecz, Katalin; Murphy, Gillian; Im, Hee-Jeong

    2011-08-11

    Abstract Introduction Cartilage degeneration driven by catabolic stimuli is a critical pathophysiological process in osteoarthritis (OA). We have defined fibroblast growth factor 2 (FGF-2) as a degenerative mediator in adult human articular...

  6. Hair growth and the fluid factor.

    PubMed

    Foote, S I

    1995-06-01

    It is accepted that the detailed mechanisms of changes in human hair growth patterns are poorly understood. It is this uncertainty that has encouraged many charlatans to operate in this area. From my perspective as an engineer, however, there is a simple mechanism that makes sense of these changes. I suggest this mechanism is closely connected with the evolution and function of hair. The fact that the presence of this mechanism can be demonstrated in the male pattern baldness scenario, raises a number of serious questions relating to fundamental physiology and the mechanisms of some serious diseases. As an amateur, it is difficult for me to gain access to up-to-date research data, so my references are derived from textbooks. I would therefore welcome comments from professionals who are involved in the areas indicated in this paper. PMID:7476592

  7. An Effect of Nerve Growth Factor on Parasympathetic Neurite Outgrowth

    NASA Astrophysics Data System (ADS)

    Collins, Frank; Dawson, Andrea

    1983-04-01

    Addition of nerve growth factor (NGF) to dissociated parasympathetic ciliary ganglion neurons resulted, within 60 min of its addition, in a 2-fold increase in average neurite length and an accompanying enlargement and spreading of neuronal growth cones. These effects occurred over a concentration range of NGF of 0.1-10 ng/ml and were blocked by affinity-purified antibody to NGF. Epidermal growth factor, fibroblast growth factor, and angiotensin did not have these effects, although insulin at high concentrations was able to induce a response similar to that of NGF. Dissociated sympathetic chain neurons also responded to NGF with increased neurite lengths, and, in addition, NGF considerably extended the survival time of these neurons in culture. However, the effect of NGF on ciliary ganglion neurons was limited to neurite outgrowth, and NGF did not promote the survival of these parasympathetic neurons.

  8. Inhibition of renal cell carcinoma angiogenesis and growth by antisense oligonucleotides targeting vascular endothelial growth factor

    PubMed Central

    Shi, W; Siemann, D W

    2002-01-01

    Angiogenesis is critical for growth and metastatic spread of solid tumours. It is tightly controlled by specific regulatory factors. Vascular endothelial growth factor has been implicated as the key factor in tumour angiogenesis. In the present studies we evaluated the effects of blocking vascular endothelial growth factor production by antisense phosphorothioate oligodeoxynucleotides on the growth and angiogenic activity of a pre-clinical model of renal cell carcinoma (Caki-1). In vitro studies showed that treating Caki-1 cells with antisense phosphorothioate oligodeoxynucleotides directed against vascular endothelial growth factor mRNA led to a reduction in expressed vascular endothelial growth factor levels sufficient to impair the proliferation and migration of co-cultured endothelial cells. The observed effects were antisense sequence specific, dose dependent, and could be achieved at a low, non-toxic concentration of phosphorothioate oligodeoxynucleotides. When vascular endothelial growth factor antisense treated Caki-1 cells were injected into nude mice and evaluated for their angiogenic potential, the number of vessels initiated were approximately half that induced by untreated Caki-1 cells. To test the anti-tumour efficacy of vascular endothelial growth factor antisense, phosphorothioate oligodeoxynucleotides were administrated to nude mice bearing macroscopic Caki-1 xenografts. The results showed that the systemic administration of two doses of vascular endothelial growth factor antisense phosphorothioate oligodeoxynucleotides given 1 and 4 days after the tumours reached a size of ?200 mm3 significantly increased the time for tumours to grow to 1000 mm3. British Journal of Cancer (2002) 87, 119–126. doi:10.1038/sj.bjc.6600416 www.bjcancer.com © 2002 Cancer Research UK PMID:12085267

  9. Epidermal ADAM17 maintains the skin barrier by regulating EGFR ligand–dependent terminal keratinocyte differentiation

    PubMed Central

    Cobzaru, Cristina; Triantafyllopoulou, Antigoni; Löffek, Stefanie; Horiuchi, Keisuke; Threadgill, David W.; Kurz, Thomas; van Rooijen, Nico; Bruckner-Tuderman, Leena

    2012-01-01

    ADAM17 (a disintegrin and metalloproteinase 17) is ubiquitously expressed and cleaves membrane proteins, such as epidermal growth factor receptor (EGFR) ligands, l-selectin, and TNF, from the cell surface, thus regulating responses to tissue injury and inflammation. However, little is currently known about its role in skin homeostasis. We show that mice lacking ADAM17 in keratinocytes (A17?KC) have a normal epidermal barrier and skin architecture at birth but develop pronounced defects in epidermal barrier integrity soon after birth and develop chronic dermatitis as adults. The dysregulated expression of epidermal differentiation proteins becomes evident 2 d after birth, followed by reduced transglutaminase (TGM) activity, transepidermal water loss, up-regulation of the proinflammatory cytokine IL-36?, and inflammatory immune cell infiltration. Activation of the EGFR was strongly reduced in A17?KC skin, and topical treatment of A17?KC mice with recombinant TGF-? significantly improved TGM activity and decreased skin inflammation. Finally, we show that mice lacking the EGFR in keratinocytes (Egfr?KC) closely resembled A17?KC mice. Collectively, these results identify a previously unappreciated critical role of the ADAM17–EGFR signaling axis in maintaining the homeostasis of the postnatal epidermal barrier and suggest that this pathway could represent a good target for treatment of epidermal barrier defects. PMID:22565824

  10. 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

  11. EMILIN1–?4/?9 integrin interaction inhibits dermal fibroblast and keratinocyte proliferation

    PubMed Central

    Danussi, Carla; Petrucco, Alessandra; Wassermann, Bruna; Pivetta, Eliana; Modica, Teresa Maria Elisa; Belluz, Lisa Del Bel; Spessotto, Paola

    2011-01-01

    EMILIN1 promotes ?4?1 integrin–dependent cell adhesion and migration and reduces pro–transforming growth factor–? processing. A knockout mouse model was used to unravel EMILIN1 functions in skin where the protein was abundantly expressed in the dermal stroma and where EMILIN1-positive fibrils reached the basal keratinocyte layer. Loss of EMILIN1 caused dermal and epidermal hyperproliferation and accelerated wound closure. We identified the direct engagement of EMILIN1 to ?4?1 and ?9?1 integrins as the mechanism underlying the homeostatic role exerted by EMILIN1. The lack of EMILIN1–?4/?9 integrin interaction was accompanied by activation of PI3K/Akt and Erk1/2 pathways as a result of the reduction of PTEN. The down-regulation of PTEN empowered Erk1/2 phosphorylation that in turn inhibited Smad2 signaling by phosphorylation of residues Ser245/250/255. These results highlight the important regulatory role of an extracellular matrix component in skin proliferation. In addition, EMILIN1 is identified as a novel ligand for keratinocyte ?9?1 integrin, suggesting prospective roles for this receptor–ligand pair in skin homeostasis. PMID:21949412

  12. EMILIN1-?4/?9 integrin interaction inhibits dermal fibroblast and keratinocyte proliferation.

    PubMed

    Danussi, Carla; Petrucco, Alessandra; Wassermann, Bruna; Pivetta, Eliana; Modica, Teresa Maria Elisa; Del Bel Belluz, Lisa; Colombatti, Alfonso; Spessotto, Paola

    2011-10-01

    EMILIN1 promotes ?4?1 integrin-dependent cell adhesion and migration and reduces pro-transforming growth factor-? processing. A knockout mouse model was used to unravel EMILIN1 functions in skin where the protein was abundantly expressed in the dermal stroma and where EMILIN1-positive fibrils reached the basal keratinocyte layer. Loss of EMILIN1 caused dermal and epidermal hyperproliferation and accelerated wound closure. We identified the direct engagement of EMILIN1 to ?4?1 and ?9?1 integrins as the mechanism underlying the homeostatic role exerted by EMILIN1. The lack of EMILIN1-?4/?9 integrin interaction was accompanied by activation of PI3K/Akt and Erk1/2 pathways as a result of the reduction of PTEN. The down-regulation of PTEN empowered Erk1/2 phosphorylation that in turn inhibited Smad2 signaling by phosphorylation of residues Ser245/250/255. These results highlight the important regulatory role of an extracellular matrix component in skin proliferation. In addition, EMILIN1 is identified as a novel ligand for keratinocyte ?9?1 integrin, suggesting prospective roles for this receptor-ligand pair in skin homeostasis. PMID:21949412

  13. 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...

  14. 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...

  15. Cutaneous adverse reactions specific to epidermal growth factor receptor inhibitors

    PubMed Central

    Lupu, I; Voiculescu, VM; Bacalbasa, N; Prie, BE; Cojocaru, I; Giurcaneanu, C

    2015-01-01

    Classical antineoplastic therapy is encumbered by extensively studied adverse reactions, most often of systemic nature. The emergence of new generations of anticancer treatments, including epidermal growth factor receptor inhibitors, besides improving the response to treatment and the survival rate, is accompanied by the occurrence of new specific side effects, incompletely studied. These side effects are most often cutaneous (hand foot syndrome, acneiform reactions), and in some cases are extremely severe, requiring dose reduction or drug discontinuation. The prevention of the cutaneous adverse effects and their treatment require a close collaboration between the oncologist and the dermatologist. The occurrence of some of these skin adverse effects may be a favorable prognostic factor for the response to the cancer treatment and the overall survival. Abbreviations: EGFR = epidermal growth factor receptors; EGFRI = epidermal growth factor receptors inhibitors PMID:26361513

  16. 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.

  17. Controlled release of growth factors on allograft bone in vitro.

    PubMed

    Huang, Zhinong; Ryu, Wonhyoung; Ren, Peigen; Fasching, Rainer; Goodman, Stuart B

    2008-08-01

    Allografts are important alternatives to autografts for treating defects after major bone loss. Bone growth factors have both local autocrine and paracrine effects and regulate the growth, proliferation, and differentiation of osteoprogenitor cells. To study the effects of prolonged, continuous, local delivery of growth factors on bone growth, we developed a new microelectromechanical system (MEMS) drug delivery device. Bone marrow cells from mice were seeded on mouse allograft discs and cultured in osteogenic media with osteogenic protein 1 (OP-1) and/or basic fibroblast growth factor (FGF-2) delivered from MEMS devices for 6 weeks. We monitored bone formation by changes of bone volume using micro-CT scanning and release of osteocalcin using ELISA. The data suggest the MEMS devices delivered constant concentrations of OP-1 and FGF-2 to the media. Bone marrow cells grew on the allografts and increased bone volume. Addition of OP-1 increased bone formation whereas FGF-2 decreased bone formation. Local delivery of growth factors over a prolonged period modulated the differentiation of osteoprogenitor cells on allograft bone. PMID:18509711

  18. 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

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

    SciTech Connect

    Merchant, Thomas E. Li Chenghong; Xiong Xiaoping; Gaber, M. Waleed

    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.

  20. Constitution of Fibrin-Based Niche for In Vitro Differentiation of Adipose-Derived Mesenchymal Stem Cells to Keratinocytes

    PubMed Central

    Sivan, Unnikrishnan; Jayakumar, K.

    2014-01-01

    Abstract 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

  1. Investigation of the insulin-like growth factor system in the avian epiphyseal growth plate.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Components of the insulin-like growth factor (IGF) system were investigated in chondrocytes isolated from the avian growth plate. The genes for IGF-I, IGF-II, IGF receptor (IGFR), IGF binding protein-2 (IGF BP-2) and IGF BP-5 were found to be expressed in both proliferative and hypertrophic chondro...

  2. 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

  3. Role for WNT16B in human epidermal keratinocyte proliferation and differentiation.

    PubMed

    Teh, Muy-Teck; Blaydon, Diana; Ghali, Lucy R; Briggs, Victoria; Edmunds, Scott; Pantazi, Eleni; Barnes, Michael R; Leigh, Irene M; Kelsell, David P; Philpott, Michael P

    2007-01-15

    WNT signalling regulates a variety of cell functions including cell fate, polarity, and differentiation via the canonical or beta-catenin stabilisation pathway and/or the planar cell polarity or non-canonical pathway. We have previously demonstrated that two isoforms (A and B) from the WNT16 locus have differential expression in various adult human tissues. In this study we show that WNT16B but not WNT16A isoform was upregulated in basal cell carcinomas compared with normal skin. We further investigated the cellular and molecular functions of WNT16B in primary human epidermal keratinocytes and a keratinocyte cell line. Cellular expression of WNT16B neither stabilised beta-catenin nor activated the lymphoid enhancer factor or T-cell factor transcriptional reporter in primary keratinocytes. WNT16B activated the Jun-N-terminal kinase cascade suggesting the activation of a non-canonical WNT signalling pathway. Constitutive expression of WNT16B significantly enhanced the rate of cell proliferation and prolonged clonogenicity in primary keratinocytes. Silencing WNT16B by RNA interference reduced keratinocyte proliferation. Furthermore, overexpression of WNT16B induced a hyperproliferation phenotype in an organotypical culture system. This work presents the first evidence that WNT16B activates human keratinocyte proliferation possibly via a beta-catenin-independent non-canonical WNT transduction pathway. PMID:17200136

  4. Engineering of the Heparin-Binding Domain of Neurotrophin-6 onto Nerve Growth Factor

    E-print Network

    Ibáñez, Carlos

    Engineering of the Heparin-Binding Domain of Neurotrophin-6 onto Nerve Growth Factor Leopold L factors. In addition to the prototypic member, nerve growth factor (NGF), other members include: brain]. Other growth factors that contain heparin-binding domains include fibroblast growth factor (FGF) [9

  5. Purified Plasma Membranes Inhibit Polypeptide Growth Factor-induced DNA Synthesis

    E-print Network

    Vale, Ronald D.

    Purified Plasma Membranes Inhibit Polypeptide Growth Factor-induced DNA Synthesis in Subconfluent 3 and/or accessibility of cells to essential growth factors in the serum (4, 5). Whittenberger factors under serum-deprived conditions. Epidermal growth factor (EGF)' (8), fibroblast growth factor (FGF

  6. 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.

  7. Phenylpropanoid glycosides from plant cell cultures induce heme oxygenase 1 gene expression in a human keratinocyte cell line by affecting the balance of NRF2 and BACH1 transcription factors.

    PubMed

    Sgarbossa, Anna; Dal Bosco, Martina; Pressi, Giovanna; Cuzzocrea, Salvatore; Dal Toso, Roberto; Menegazzi, Marta

    2012-08-30

    Phenylpropanoids have several highly significant biological properties in both plants and animals. Four phenylpropanoid glycosides (PPGs), verbascoside (VB), forsythoside B (FB), echinacoside (EC) and campneoside I (CP), were purified and tested for their capability to activate NRF2 and induce phase II cytoprotective enzymes in a human keratinocyte cell line (HaCaT). All four substances showed similar strong antioxidant and radical-scavenging activities as determined by diphenylpicrylhydrazyl assay. Furthermore, in HaCaT cells, FB and EC are strong activators of NRF2, the nuclear transcription factor regulating many phase II detoxifying and cytoprotective enzymes, such as heme oxygenase 1 (HMOX1). In HaCaT cells, FB and EC (200 ?M) induced nuclear translocation of NRF2 protein after 24 h and reduced nuclear protein levels of BACH1, a repressor of the antioxidant response element. FB and EC greatly HMOX1 mRNA levels by more than 40-fold in 72 h. Cytoplasmic HMOX1 protein levels were also increased at 48 h after treatment. VB was less active compared to FB and EC, and CP was slightly active only at later times of treatment. We suggest that hydroxytyrosol (HYD) could be a potential bioactive metabolite of PPGs since HYD, in equimolar amounts to PGGs, is able to both activate HO-1 transcription and modify Nrf2/Bach1 nuclear protein levels. This is in agreement with the poor activity of CP, which contains a HYD moiety modified by an O-methyl group. In conclusion, FB and EC from plant cell cultures may provide long-lasting skin protection by induction of phase II cytoprotective capabilities. PMID:22735309

  8. Cultured human foreskin fibroblasts produce a factor that stimulates their growth with properties similar to basic fibroblast growth factor

    SciTech Connect

    Story, M.T. )

    1989-05-01

    To determine if fibroblasts could be a source of fibroblast growth factor (FGF) in tissue, cells were initiated in culture from newborn human foreskin. Fibroblast cell lysates promoted radiolabeled thymidine uptake by cultured quiescent fibroblasts. Seventy-nine percent of the growth-promoting activity of lysates was recovered from heparin-Sepharose. The heparin-binding growth factor reacted on immunoblots with antiserum to human placenta-derived basic FGF and competed with iodinated basic FGF for binding to antiserum to (1-24)bFGF synthetic peptide. To confirm that fibroblasts were the source of the growth factor, cell lysates were prepared from cells incubated with radiolabeled methionine. Heparin affinity purified material was immunoprecipitated with basic FGF antiserum and electrophoresed. Radiolabeled material was detected on gel autoradiographs in the same molecular weight region as authentic iodinated basic FGF. The findings are consistant with the notion that cultured fibroblasts express basic FGF. As these cells also respond to the mitogen, it is possible that the regulation of their growth is under autocrine control. Fibroblasts may be an important source of the growth factor in tissue.

  9. Stimulatory effect of luteinizing hormone, insulin-like growth factor-1, and epidermal growth factor on vascular endothelial growth factor production in cultured bubaline luteal cells.

    PubMed

    Chouhan, V S; Dangi, S S; Babitha, V; Verma, M R; Bag, S; Singh, G; Sarkar, M

    2015-10-15

    The purpose of this study was to evaluate the temporal (24, 48, and 72 hours) and dose-dependent (0, 5, 10, and 100 ng/mL of LH, insulin-like growth factor 1 [IGF-1], and EGF) in vitro expression and secretion patterns of vascular endothelial growth factor (VEGF) in luteal cell culture during different stages of estrous cycle in water buffaloes. Corpus luteum samples from ovaries of early luteal phase (ELP; Days 1-4), midluteal phase (Days 5-10), and late luteal phase (Days 11-16) were collected from a local slaughterhouse. The samples were then processed and cultured in (serum containing) appropriate cell culture medium and incubated separately with three factors (LH, IGF-1, or EGF) at the previously mentioned three dose-duration combinations. At the end of the respective incubation periods, VEGF was assayed in the spent culture medium by ELISA, whereas the cultured cells were used for VEGF mRNA expression by quantitative real-time polymerase chain reaction. The results of the present study disclosed dose- and time-dependent stimulatory effects of LH, IGF-1, and EGF on VEGF production in bubaline luteal cells. The VEGF expression and secretion from the cultured luteal cells were highest during the ELP, intermediate in the midluteal phase, and lowest in the late luteal phase of the estrous cycle for all the three tested factors. Comparison of the results of the three treatments depicted EGF as the most potent stimulating factor followed by IGF-1 and LH. Immunocytochemistry findings in luteal cell culture of ELP agreed with the VEGF expression and secretion. In conclusion, mRNA expression, protein secretion, and immunolocalization of VEGF data clearly indicated for the first time that LH, IGF-1, and EGF play an important role in stimulating luteal angiogenesis in buffalo CL. The highest expression and secretion of VEGF in the ELP might be associated with the development of blood vessels in early growth of CL, which in turn gets augmented by the aforementioned factors emphasizing their regulatory role in luteal angiogenesis. Further studies are however necessary to divulge more information on other factors which regulate VEGF secretion in bubaline CL and the synergistic effects existing among such growth factors. PMID:26242566

  10. Dendrimer-epidermal growth factor conjugate displays superagonist activity.

    PubMed

    Thomas, Thommey P; Shukla, Rameshwer; Kotlyar, Alina; Liang, Bradley; Ye, Jing Yong; Norris, Theodore B; Baker, James R

    2008-02-01

    Binding of ligands on to epidermal growth factor receptor (EGFR) can stimulate cell growth; therefore, any application employing EGF as a targeting ligand for a "drug carrier" must evaluate the effect of the conjugate on cell growth. We report the synthesis and in vitro biological activity of EGF molecules coupled to a fluorescein-labeled polyamidoamine dendrimer. The conjugate bound and internalized into several EGFR-expressing cell lines in a receptor-specific fashion. The conjugate effectively induced EGFR phosphorylation and acted as a superagonist by stimulating cell growth to a greater degree than free EGF. Concomitant administration of the chemotherapeutic drug methotrexate completely inhibited cell growth to a degree similar to its effect in the absence of the conjugate. Thus, dendrimer-EGF conjugates serve as EGFR superagonists, but this activity can be overcome by chemotherapeutic drugs. The agonist activity of these materials must be taken into consideration when using EGF conjugates for imaging applications. PMID:18193839

  11. Factor VII Deficiency Impairs Cutaneous Wound Healing in Mice

    PubMed Central

    Xu, Zhi; Xu, Haifeng; Ploplis, Victoria A; Castellino, Francis J

    2010-01-01

    Skin keratinocytes express tissue factor (TF) and are highly associated with skin wound healing. Although it has been demonstrated that perivascular TF expression in granulation tissue formed after dermal injury is downregulated during healing, studies of the mechanism of factor (F) VII, a TF ligand, in skin wound healing are lacking. We reported the use of a dermal punch model to demonstrate that low-expressing FVII mice (~1% of wild type [WT]) exhibited impaired skin wound healing compared with WT controls. These low-FVII mice showed defective reepithelialization and reduced inflammatory cell infiltration at wound sites. This attenuated reepithelialization was associated with diminished expression of the transcription factor early growth response 1 (Egr-1). In vitro, Egr-1 was shown to be essential for the FVIIa-induced regulation of keratinocyte migration and inflammation. Both Egr-1 upregulation and downstream inflammatory cytokine appearance in keratinocytes depended on FVIIa/TF/protease-activated receptor 2 (PAR-2)-induced signaling and did not require subsequent generation of FXa and thrombin. The participation of Egr-1 in FVIIa-mediated regulation of keratinocyte function was confirmed by use of Egr-1–deficient mice, wherein a significant delay in skin wound healing after injury was observed, relative to WT mice. The results from these studies demonstrate an in vivo mechanistic relationship between FVIIa, Egr-1 and the inflammatory response in keratinocyte function during the wound healing process. PMID:20454518

  12. Vascular growth factors play critical roles in kidney glomeruli.

    PubMed

    Gnudi, Luigi; Benedetti, Sara; Woolf, Adrian S; Long, David A

    2015-12-01

    Kidney glomeruli ultrafilter blood to generate urine and they are dysfunctional in a variety of kidney diseases. There are two key vascular growth factor families implicated in glomerular biology and function, namely the vascular endothelial growth factors (VEGFs) and the angiopoietins (Angpt). We present examples showing not only how these molecules help generate and maintain healthy glomeruli but also how they drive disease when their expression is dysregulated. Finally, we review how manipulating VEGF and Angpt signalling may be used to treat glomerular disease. PMID:26561594

  13. Newly discovered olfactory receptors in epidermal keratinocytes are associated with proliferation, migration, and re-epithelialization of keratinocytes.

    PubMed

    Denda, Mitsuhiro

    2014-11-01

    Skin contains receptors for various environmental factors. In this issue of the Journal, Busse et al. cloned a new olfactory receptor, OR2AT4, in keratinocytes. They show that the activation of OR2AT4 induces phosphorylation of extracellular signal-regulated kinases and p38 mitogen-activated protein kinases, and that it accelerates wound healing. OR2AT4 may be a promising candidate as a target in clinical drug development. PMID:25318430

  14. A transforming growth factor beta-like immunosuppressive factor in immunoglobulin G-binding factor

    PubMed Central

    1995-01-01

    Immunoglobulin G-binding factors (IgG-BF), which are produced by cells of the immune system, inhibit antibody production. In this paper, we show that transforming growth factor-beta (TGF-beta) suppresses secondary in vitro anti-sheep red blood cell responses of mouse splenocytes and lipopolysaccharide- or anti-IgM-stimulated mouse B cell responses in a way similar to, and with the same kinetics as, rodent IgG-BF. Moreover, the immunosuppressive activity of IgG-BF was totally neutralized by polyclonal and monoclonal anti-TGF-beta antibodies and it eluted with TGF-beta by gel exclusion chromatography, suggesting that a TGF-beta-like immunosuppressive factor is present in IgG-BF. We also show that TGF-beta behaves as an IgG-BF since it binds to insolubilized IgG, but not to insolubilized F(ab')2 or bovine serum albumin. Altogether, the data support the concept of a biological role for TGF-beta in the IgG-mediated negative feedback of antibody responses. PMID:7500016

  15. Cytokines and growth factors which regulate bone cell function

    NASA Astrophysics Data System (ADS)

    Seino, Yoshiki

    Everybody knows that growth factors are most important in making bone. Hormones enhance bone formation from a long distance. Growth factors promote bone formation as an autocrine or paracrine factor in nearby bone. BMP-2 through BMP-8 are in the TGF-? family. BMP makes bone by enchondral ossification. In bone, IGF-II is most abundant, second, TGF-?, and third IGF-I. TGF-? enhances bone formation mainly by intramembranous ossification in vivo. TGF-? affects both cell proliferation and differentiation, however, TGF-? mainly enhances bone formation by intramembranous ossification. Interestingly, TGF-? is increased by estrogen(E 2), androgen, vitamin D, TGF-? and FGF. IGF-I and IGF-II also enhance bone formation. At present it remains unclear why IGF-I is more active in bone formation than IGF-II, although IGF-II is more abundant in bone compared to IGF-I. However, if only type I receptor signal transduction promotes bone formation, the strong activity of IGF-I in bone formation is understandable. GH, PTH and E 2 promotes IGF-I production. Recent data suggest that hormones containing vitamin D or E 2 enhance bone formation through growth factors. Therefore, growth factors are the key to clarifying the mechanism of bone formation.

  16. Coexpression of transforming growth factor-alpha and épidermal growth factor receptor in capillary hemangioblastomas of the central nervous system.

    PubMed Central

    Reifenberger, G.; Reifenberger, J.; Bilzer, T.; Wechsler, W.; Collins, V. P.

    1995-01-01

    The expression of epidermal growth factor receptor (EGFR) and the pre-pro form of one of its ligands, transforming growth factor-alpha (TGF-alpha), was studied by Northern blotting in a series of 14 capillary hemangioblastomas of the central nervous system. A constant coexpression of EGFR and pre-pro-TGF-alpha mRNAs was found. Immunocytochemical investigation of an extended series of 51 capillary hemangioblastomas revealed that the stromal cells in these tumors showed immunoreactivity with monoclonal antibodies to EGFR and TGF-alpha. Analysis of gene dosage by Southern blotting in 20 tumors indicated a normal gene copy number of EGFR and TGF alpha in all cases. Our findings suggest that autocrine and/or juxtacrine growth stimulation via the EGFR may contribute to tumor growth in capillary hemangioblastomas. Images Figure 2 Figure 1 Figure 3 PMID:7639324

  17. Vascular endothelial growth factors: A comparison between invertebrates and vertebrates.

    PubMed

    Kipryushina, Yulia O; Yakovlev, Konstantin V; Odintsova, Nelly A

    2015-12-01

    This review aims to summarize recent data concerning the structure and role of the members of the vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptor (VEGFR) families in the context of early development, organogenesis and regeneration, with a particular emphasis on the role of these factors in the development of invertebrates. Homologs of VEGF and/or VEGFR have been found in all Eumetazoa, in both Radiata and Bilateria, where they are expressed in the descendants of different germ layers and play a pivotal role in the development of animals with and without a vascular system. VEGF is a well-known angiogenesis regulator, but this factor also control cell migration during neurogenesis and the development of branching organs (the trachea) in invertebrate and vertebrate species. A possible explanation for the origin of Vegf/Vegfr in the animal kingdom and a pathway of Vegf/Vegfr evolution are discussed. PMID:26066416

  18. Growth factors in the treatment of early osteoarthritis.

    PubMed

    Civinini, Roberto; Nistri, Lorenzo; Martini, Caterina; Redl, Birgit; Ristori, Gabriele; Innocenti, Massimo

    2013-01-01

    Regenerative medicine is the science that studies the regeneration of biological tissues obtained through use of cells, with the aid of support structures and with biomolecules such as growth factors. As regards the growth factors the PRP, or the platelet-rich plasma, obtained from a withdrawal of autologous blood, concentrating the platelets, represents a safe, economical, easy to prepare and easy to apply source of growth factors. Numerous growth factors are in fact within the platelets and in particular a large number of them have a specific activity on neo-proliferation, on cartilage regeneration and in particular also an antiapoptotic effect on chondroblasts: - The PDGF which regulates the secretion and synthesis of collagen;- The EGF that causes cellular proliferation, endothelial chemotaxis and angiogenesis;- The VEGF that increases angiogenesis and vascular permeability;- The TGF-beta that stimulates the proliferation of undifferentiated MSC, stimulates chemotaxis of endothelial cells and angiogenesis;- The bFGF that promotes the growth and differentiation of chondrocytes and osteoblasts stimulates mitogenesis of mesenchymal cells, chondrocytes and osteoblasts. These properties have led to the development of studies that evaluated the efficacy of treatment of infiltrations in the knee and hip with platelet-derived growth factors. Regarding the knee it was demonstrated that in patients with moderate degree of gonarthrosis, the PRP is able to significantly reduce the pain and improve joint function, both on placebo and towards infiltrations with hyaluronic acid. The success of the treatment was proportional to the age of and inversely proportional to the severity of osteoarthritis according to Kellgren and Lawrence classification. The possibility of infiltrations guided with ultrasound into the hip led us to extend the indications also to hip arthrosis, as already showed by Sanchez. Even in coxarthrosis preliminary results at 6 and 12 months show that a cycle of 3 infiltrations of PRP has significantly decreased the pain and increased range of motion and joint function. PMID:23858307

  19. Granulocyte-macrophage colony-stimulating factor (GM-CSF) controls the proliferation and differentiation of mouse epidermal melanocytes from pigmented spots induced by ultraviolet radiation B.

    PubMed

    Hirobe, Tomohisa; Furuya, Rikako; Hara, Eijiro; Horii, Izumi; Tsunenaga, Makoto; Ifuku, Ohji

    2004-06-01

    Repeated exposure of ultraviolet radiation B (UVB) on the dorsal skin of hairless mice induces the development of pigmented spots long after its cessation. The proliferation and differentiation of epidermal melanocytes in UVB-induced pigmented spots are greatly increased, and those effects are regulated by keratinocytes rather than by melanocytes. However, it remains to be resolved what factor(s) derived from keratinocytes are involved in regulating the proliferation and differentiation of epidermal melanocytes. In this study, primary melanoblasts (c. 80%) and melanocytes (c. 20%) derived from epidermal cell suspensions of mouse skin were cultured in a basic fibroblast growth factor-free medium supplemented with granulocyte-macrophage colony-stimulating factor (GM-CSF). GM-CSF induced the proliferation and differentiation of melanocytes in those keratinocyte-depleted cultures. Moreover, an antibody to GM-CSF inhibited the proliferation of melanoblasts and melanocytes from epidermal cell suspensions derived from the pigmented spots of UV-irradiated mice, but not from control mice. Further, the GM-CSF antibody inhibited the proliferation and differentiation of melanocytes co-cultured with keratinocytes derived from UV-irradiated mice, but not from control mice. The quantity of GM-CSF secreted from keratinocytes derived from the pigmented spots of UV-irradiated mice was much greater than that secreted from keratinocytes derived from control mice. Moreover, immunohistochemistry revealed the expression of GM-CSF in keratinocytes derived from the pigmented spots of skin in UV-irradiated mice, but not from normal skin in control mice. These results suggest that GM-CSF is one of the keratinocyte-derived factors involved in regulating the proliferation and differentiation of mouse epidermal melanocytes from UVB-induced pigmented spots. PMID:15140068

  20. 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

  1. Insulin-Like Growth Factor I (IGF-1) Ec/Mechano Growth Factor – A Splice Variant of IGF-1 within the Growth Plate

    PubMed Central

    Schlegel, Werner; Raimann, Adalbert; Halbauer, Daniel; Scharmer, Daniela; Sagmeister, Susanne; Wessner, Barbara; Helmreich, Magdalena; Haeusler, Gabriele; Egerbacher, Monika

    2013-01-01

    Human insulin-like growth factor 1 Ec (IGF-1Ec), also called mechano growth factor (MGF), is a splice variant of insulin-like growth factor 1 (IGF-1), which has been shown in vitro as well as in vivo to induce growth and hypertrophy in mechanically stimulated or damaged muscle. Growth, hypertrophy and responses to mechanical stimulation are important reactions of cartilaginous tissues, especially those in growth plates. Therefore, we wanted to ascertain if MGF is expressed in growth plate cartilage and if it influences proliferation of chondrocytes, as it does in musculoskeletal tissues. MGF expression was analyzed in growth plate and control tissue samples from piglets aged 3 to 6 weeks. Furthermore, growth plate chondrocyte cell culture was used to evaluate the effects of the MGF peptide on proliferation. We showed that MGF is expressed in considerable amounts in the tissues evaluated. We found the MGF peptide to be primarily located in the cytoplasm, and in some instances, it was also found in the nucleus of the cells. Addition of MGF peptides was not associated with growth plate chondrocyte proliferation. PMID:24146828

  2. Clinical significance of heparin-binding epidermal growth factor-like growth factor in peritoneal fluid of ovarian cancer

    PubMed Central

    Yagi, H; Miyamoto, S; Tanaka, Y; Sonoda, K; Kobayashi, H; Kishikawa, T; Iwamoto, R; Mekada, E; Nakano, H

    2005-01-01

    Epidermal growth factor receptor (EGFR) has been implicated in tumour growth and extension of ovarian cancer. Peritoneal fluid in ovarian cancer patients contains various growth factors that can promote tumour growth and extension. In order to investigate the clinical significance of EGFR ligands as activating factors of ovarian cancer, we examined the cell proliferation-promoting activity and the level of EGFR ligands in peritoneal fluid obtained from 99 patients. Proliferation-promoting activity in peritoneal fluid from 63 ovarian cancer patients (OVCA) was much higher than peritoneal fluid from 18 ovarian cyst patients (OVC) and 18 normal ovary patients (NO), and the activity was suppressed only by antibodies against EGFR or heparin-binding epidermal growth factor (HB-EGF). A large difference was observed in the level of EGFR ligands between HB-EGF and TGF-? or amphiregulin. The concentration of HB-EGF in OVCA significantly increased compared to that in OVC or NO (P<0.01). No significant difference in the concentration of TGF-? and amphiregulin was found between the OVCA and NO or OVC groups. In peritoneal fluid, HB-EGF is sufficiently elevated to activate cancer cells even at an early stage of OVCA. These results suggested that HB-EGF in peritoneal fluid might play a key role in cell survival and in the proliferation of OVCA. PMID:15827558

  3. Discovering Small Molecule Ligands of Vascular Endothelial Growth Factor

    E-print Network

    Zhu, Xiangdong

    receptor (KDR) and the fms-like tyrosine kinase (Flt-1). VEGF in a dimeric form binds to extracellular in angiogenesis through binding to cell-surface receptors of the tyrosine kinase family such as the kinase domain-based assay platform that we used to identify inhibitors of vascular endothelial growth factor (VEGF)­ kinase

  4. Fibroblast Growth Factor-2 Alters the Nature of Extinction

    ERIC Educational Resources Information Center

    Graham, Bronwyn M.; Richardson, Rick

    2011-01-01

    These experiments examined the effects of the NMDA-receptor (NMDAr) antagonist MK801 on reacquisition and re-extinction of a conditioned fear that had been previously extinguished before injection of fibroblast growth factor-2 (FGF2) or vehicle. Recent findings have shown that relearning and re-extinction, unlike initial learning and extinction,…

  5. Lipopolysaccharide Potentiates the Effect of Hepatocyte Growth Factor upon Replication

    E-print Network

    Ponder, Katherine P.

    Lipopolysaccharide Potentiates the Effect of Hepatocyte Growth Factor upon Replication in Lung in revised form January 10, 2001; published online April 13, 2001 Induction of replication may potentiate) increases the percentage of replicating hepatocytes to 18-fold that in normal rats, and lipopolysaccharide

  6. INTRODUCTION Neurotrophins are a family of soluble growth factors required

    E-print Network

    Ibáñez, Carlos

    INTRODUCTION Neurotrophins are a family of soluble growth factors required for the survival at supporting limb muscle sensory neurons in vitro (Horylee et al., 1993). It is expressed in skeletal muscle the survival of muscle sensory neurons (Oakley et al., 1995). NT3 is also expressed in developing DRG

  7. An Atomic Resolution Structure for Human Fibroblast Growth Factor 1

    E-print Network

    Blaber, Michael

    An Atomic Resolution Structure for Human Fibroblast Growth Factor 1 Matthew J. Bernett. The backbone atoms of each structurally conserved region of the symmetry-related subdomains in FGF-1 overlay and Biochemistry, Florida State University, Tallahassee, Florida ABSTRACT A 1.10-Å atomic resolution X

  8. NEUROBIOLOGICAL EFFECTS OF COLCHICINE: MODULATION BY NERVE GROWTH FACTOR

    EPA Science Inventory

    To study the effects of exogenously applied nerve growth factor (NGF) on colchicine-induced neurodegeneration in the dentate gyrus of the rat hippocampal formation, male Fischer 344 rats (n=75) weighing 275-325 grams received colchicine [COLCH; 2.5 ug/site in 0.5 ul of artificial...

  9. 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.

  10. Total Chemical Synthesis of Biologically Active Vascular Endothelial Growth Factor

    SciTech Connect

    Mandal, Kalyaneswar; Kent, Stephen B.H.

    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.

  11. 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

  12. Carbachol stimulates a different phospholipid metabolism than nerve growth factor and basic fibroblast growth factor in PC12 cells.

    PubMed Central

    Pessin, M S; Altin, J G; Jarpe, M; Tansley, F; Bradshaw, R A; Raben, D M

    1991-01-01

    We have examined 1,2-diglycerides (DGs) generated in PC12 cells in response to the muscarinic agonist carbachol and compared them with those generated in response to the differentiation factors nerve growth factor and basic fibroblast growth factor. Whereas carbachol stimulates a greater release of inositol phosphates, all three agonists generate similar levels of DGs. In this report, we have analyzed the molecular species of PC12 DGs generated in response to these three agonists. Additionally, we have analyzed the molecular species of PC12 phospholipids. The data indicate that 1) after 1 min of either nerve growth factor or basic fibroblast growth factor stimulation, DGs arise primarily from phosphoinositide hydrolysis; 2) in contrast, after 1 min of carbachol stimulation, DG are generated equally by both phosphoinositide and phosphatidylcholine hydrolysis; and 3) after 15 min of stimulation by any of these agonists, DGs are generated largely by phosphatidylcholine hydrolysis, with a smaller component arising from the phosphoinositides. These results suggest that at least part of the mechanism by which PC12 cells distinguish between different agonists is via alterations in phospholipid sources and kinetics of DG generation. PMID:1892912

  13. Shear stress magnitude and directionality modulate growth factor gene expression in

    E-print Network

    Passerini, Tony

    Shear stress magnitude and directionality modulate growth factor gene expression in preconditioned levels of 12 endothelial growth factor genes in response to alterations in wall shear stress (WSS) under nitric oxide synthase (NOS3), platelet-derived growth factor A, platelet-derived growth factor B (PDGFB

  14. Growth factor receptors, lipid rafts and caveolae: An evolving story Linda J. Pike*

    E-print Network

    Pike, Linda J.

    Review Growth factor receptors, lipid rafts and caveolae: An evolving story Linda J. Pike; accepted 13 May 2005 Available online 31 May 2005 Abstract Growth factor receptors have been shown domains in growth factor receptor function, the binding and kinase activities of growth factor receptors

  15. Curcumin upregulates insulin-like growth factor binding protein-5 (IGFBP-5) and C/EBPalpha during oral cancer suppression.

    PubMed

    Chang, Kuo-Wei; Hung, Pei-Shih; Lin, I-Ying; Hou, Chung-Ping; Chen, Li-Kai; Tsai, Yin-Meng; Lin, Shu-Chun

    2010-07-01

    Curcumin is a common food ingredient derived from the plant Curcuma longa and is a potent drug against tumorigenesis. Both insulin-like growth factor binding protein-5 (IGFBP-5) and CCAAT/enhancer-binding protein alpha (C/EBPalpha) are suppressors of head and neck carcinogenesis. We identified curcumin as an inducer of IGFBP-5 expression in multiple types of oral keratinocytes; furthermore, curcumin induces IGFBP-5 promoter activity in SAS oral cancer cells. Promoter deletion mapping identified a region (nt -71 to nt -59 relative to the transcription start site) as containing a C/EBPalpha-binding element that is indispensable for curcumin-mediated IGFBP-5 upregulation. Chromatin immunoprecipitation assays revealed that in vivo binding of C/EBPalpha to this region was remarkably increased in the presence of curcumin. Curcumin increased nuclear C/EBPalpha expression and IGFBP-5 expression through p38 activation and this was abrogated by SB203580 treatment. Furthermore, MKK6 expression activated p38 and C/EBPalpha, increasing IGFBP-5 promoter activity and expression. Finally, curcumin-induced IGFBP-5 expression is associated with the suppression of xenograft tumorigenesis in mice due to oral cancer cells. We conclude that curcumin activates p38, which, in turn, activates the C/EBPalpha transactivator by interacting with binding elements in the IGFBP-5 promoter. The consequential upregulation of C/EBPalpha and IGFBP-5 by curcumin is crucial to the suppression of oral carcinogenesis. PMID:20127863

  16. Endothelial Cell Migration and Vascular Endothelial Growth Factor Expression Are the Result of Loss of Breast Tissue Polarity

    E-print Network

    Kenny, Paraic

    Endothelial Cell Migration and Vascular Endothelial Growth Factor Expression Are the Result of Loss, growth- arrested nonmalignant counterparts. Elevated vascular endo- thelial growth factor (VEGF factors have been identified, the most prominent being vascular endothelial growth factor (VEGF), which

  17. Neurodevelopmental effects of insulin-like growth factor signaling

    PubMed Central

    O’Kusky, John; Ye, Ping

    2012-01-01

    Insulin-like growth factor (IGF) signaling greatly impacts the development and growth of the central nervous system (CNS). IGF-I and IGF-II, two ligands of the IGF system, exert a wide variety of actions both during development and in adulthood, promoting the survival and proliferation of neural cells. The IGFs also influence the growth and maturation of neural cells, augmenting dendritic growth and spine formation, axon outgrowth, synaptogenesis, and myelination. Specific IGF actions, however, likely depend on cell type, developmental stage, and local microenvironmental milieu within the brain. Emerging research also indicates that alterations in IGF signaling likely contribute to the pathogenesis of some neurological disorders. This review summarizes experimental studies and shed light on the critical roles of IGF signaling, as well as its mechanisms, during CNS development. PMID:22710100

  18. Vascular permeability factor/vascular endothelial growth factor, microvascular hyperpermeability, and angiogenesis.

    PubMed Central

    Dvorak, H. F.; Brown, L. F.; Detmar, M.; Dvorak, A. M.

    1995-01-01

    VPF/VEGF is a multifunctional cytokine that contributes to angiogenesis by both direct and indirect mechanisms. On the one hand, VPF/VEGF stimulates the ECs lining nearby microvessels to proliferate, to migrate, and to alter their pattern of gene expression. On the other hand, VPF/VEGF renders these same microvascular ECs hyperpermeable so that they spill plasma proteins into the extravascular space, leading to the clotting of extravasated fibrinogen with deposition of a fibrin gel. Extravascular fibrin serves as a provisional matrix that favors and supports the ingrowth of new blood vessels and other mesenchymal cells that generate mature, vascularized stroma. These same principles apply in tumors, in several examples of non-neoplastic pathology, and in physiological processes that involve angiogenesis and new stroma generation. In all of these examples, microvascular hyperpermeability and the introduction of a provisional, plasma-derived matrix precede and accompany the onset of EC division and new blood vessel formation. It would seem, therefore, that tumors have "borrowed" fundamental mechanisms that developed in multicellular organisms for purposes of tissue defense, renewal, and repair. VPF/VEGF, therefore has taught us something new about angiogenesis; namely, that vascular hyperpermeability and consequent plasma protein extravasation are important, perhaps essential, elements in its generation. However, this finding raises a paradox. While VPF/VEGF induces vascular hyperpermeability, other potent angiogenic factors apparently do not, at least in subtoxic concentrations that are more than sufficient to induce angiogenesis. Nonetheless, wherever angiogenesis has been studied, the newly generated vessels have been found to be hyperpermeable. How, therefore, do angiogenic factors other than VPF/VEGF lead to the formation of new and leaky blood vessels? We do not as yet have a complete answer to this question. One possibility is that at least some angiogenic factors mediate their effect by inducing or stimulating the expression of VPF/VEGF. In fact, there is already one clear example of this. TGF-alpha is a potent angiogenic factor but does not itself increase microvascular permeability. However, TGF-alpha strikingly upregulates VPF/VEGF expression in cultured keratinocytes and is thought to be responsible, at least in part, for the overexpression of VPF/VEGF in psoriasis. Moreover, overexpression of TGF-alpha, along with that of the EGF receptor with which it interacts, is characteristic of many malignant tumors, raising the possibility that TGF-alpha acts to stimulate VPF/VEGF expression in other types of epithelial cells and in this manner induces angiogenesis.(ABSTRACT TRUNCATED AT 400 WORDS) PMID:7538264

  19. Induction of nerve growth factor receptors on cultured human melanocytes

    SciTech Connect

    Peacocke, M.; Yaar, M.; Mansur, C.P.; Chao, M.V.; Gilchrest, B.A. )

    1988-07-01

    Normal differentiation and malignant transformation of human melanocytes involve a complex series of interactions during which both genetic and environmental factors play roles. At present, the regulation of these processes is poorly understood. The authors have induced the expression of nerve growth factor (NGF) receptors on cultured human melanocytes with phorbol 12-tetradecanoate 13-acetate and have correlated this event with the appearance of a more differentiated, dendritic morphology. Criteria for NGF receptor expression included protein accumulation and cell-surface immunofluorescent staining with a monoclonal antibody directed against the human receptor and induction of the messenger RNA species as determined by blot-hybridization studies. The presence of the receptor could also be induced by UV irradiation or growth factor deprivation. The NGF receptor is inducible in cultured human melanocytes, and they suggest that NGF may modulate the behavior of this neural crest-derived cell in the skin.

  20. 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.

  1. HPV Type 16 Infection Switches Keratinocytes from Apoptotic to Proliferative Fate under TWEAK/Fn14 Interaction.

    PubMed

    Cheng, Hong; Zhan, Na; Ding, Dong; Liu, Xiaoming; Zou, Xiaoyan; Li, Ke; Xia, Yumin

    2015-10-01

    Previously, tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) had been known to be an inducer of apoptosis of keratinocytes by engaging the Fn14 receptor. However, the high-risk human papillomavirus (HPV) infection confers a proliferation advantage on keratinocytes that may consequently harbor tumorigenicity. This study was designed to investigate the cross-talk in keratinocytes between TWEAK/Fn14 signaling and HPV type 16 infection, which may cooperate in regulating cell-cycle progression. TWEAK and Fn14 expression was determined in anogenital warts and normal skin. Both primary keratinocytes and HaCaT cells were transfected with HPV16 E6/E7 genes. The results showed that Fn14 is highly expressed upon HPV16 transfection and accompanied by an increase in Ras GTPase activity and TNF-receptor-associated factor 2 (TRAF2) expression. Moreover, the E6/E7-transfected keratinocytes exhibit a shift of TNF receptor profile from type 1 to type 2 and weakened apoptotic response to TNF-? stimuli, when compared with the normal control. Surprisingly, significant increase in proliferation but not apoptosis was seen in E6/E7-positive keratinocytes, as TWEAK was additionally supplemented. In conclusion, the HPV16 infection in keratinocytes causes a switch of apoptotic to proliferative fate under TWEAK/Fn14 interaction, possibly by favoring Ras and TRAF2 activation and modulating TNF receptor expression. PMID:26016896

  2. The importance of neuronal growth factors in the ovary.

    PubMed

    Streiter, S; Fisch, B; Sabbah, B; Ao, A; Abir, R

    2016-01-01

    The neurotrophin family consists of nerve growth factor (NGF), neurotrophin 3 (NT3) and neurotrophin 4/5 (NT4/5), in addition to brain-derived neurotrophic factor (BDNF) and the neuronal growth factors, glial cell line-derived neurotrophic factor (GDNF) and vasointestinal peptide (VIP). Although there are a few literature reviews, mainly of animal studies, on the importance of neurotrophins in the ovary, we aimed to provide a complete review of neurotrophins as well as neuronal growth factors and their important roles in normal and pathological processes in the ovary. Follicular assembly is probably stimulated by complementary effects of NGF, NT4/5 and BDNF and their receptors. The neurotrophins, GDNF and VIP and their receptors have all been identified in preantral and antral follicles of mammalian species, including humans. Transgenic mice with mutations in the genes encoding for Ngf, Nt4/5 and Bdnf and their tropomyosin-related kinase ? receptor showed a reduction in preantral follicles and an abnormal ovarian morphology, whereas NGF, NT3, GDNF and VIP increased the in vitro activation of primordial follicles in rats and goats. Additionally, NGF, NT3 and GDNF promoted follicular cell proliferation; NGF, BDNF and VIP were shown to be involved in ovulation; VIP inhibited follicular apoptosis; NT4/5, BDNF and GDNF promoted oocyte maturation and NGF, NT3 and VIP stimulated steroidogenesis. NGF may also exert a stimulatory effect in ovarian cancer and polycystic ovarian syndrome (PCOS). Low levels of NGF and BDNF in follicular fluid may be associated with diminished ovarian reserve and high levels with endometriosis. More knowledge of the roles of neuronal growth factors in the ovary has important implications for the development of new therapeutic drugs (such as anti-NGF agents) for ovarian cancer and PCOS as well as various infertility problems, warranting further research. PMID:26487421

  3. Stimulation of glucose uptake by transforming growth factor. beta. : evidence for the requirement of epidermal growth factor-receptor activation

    SciTech Connect

    Inman, W.H.; Colowick, S.P.

    1985-03-01

    Transforming growth factor ..beta.. (TGF-..beta..), derived from human platelets, stimulates the uptake of 2-deoxyglucose by cultured cell monolayers 2- to 4-fold. Stimulation can be detected as early as 30 min with as little as 0.1 ng of TGF-..beta.. per ml and maximal effects can be obtained at 2 hr with 1 ng of the growth factor per ml. TGF-..beta..-induced stimulation of sugar uptake is enhanced by the co-addition of platelet-derived growth factor (10 ng/ml) or epidermal growth factor (EGF, 1 ng/ml). The NR-6 variant of mouse 3T3 cells, which lack EGF receptors, is not stimulated by TGF-..beta... Antisera to EGF receptors that block /sup 125/I-labeled EGF binding also inhibit TGF-..beta.. stimulation of 2-deoxyglucose uptake, although /sup 125/I-labeled TGF-..beta.. binding remains unimpaired. In contrast, antisera to the EGF receptor, which do not block EGF binding, have no measurable effect on the TGF-..beta..-stimulated uptake of 2-deoxyglucose. The authors confirm that the receptor for TGF-..beta.. is distinct from the receptor for EGF and the authors conclude that TGF-..beta.. stimulation of 2-deoxyglucose uptake requires the co-activation of the EGF receptor kinase system.

  4. Extrinsic Factors Influencing Fetal Deformations and Intrauterine Growth Restriction

    PubMed Central

    Moh, Wendy; Graham, John M.; Wadhawan, Isha; Sanchez-Lara, Pedro A.

    2012-01-01

    The causes of intrauterine growth restriction (IUGR) are multifactorial with both intrinsic and extrinsic influences. While many studies focus on the intrinsic pathological causes, the possible long-term consequences resulting from extrinsic intrauterine physiological constraints merit additional consideration and further investigation. Infants with IUGR can exhibit early symmetric or late asymmetric growth abnormality patterns depending on the fetal stage of development, of which the latter is most common occurring in 70–80% of growth-restricted infants. Deformation is the consequence of extrinsic biomechanical factors interfering with normal growth, functioning, or positioning of the fetus in utero, typically arising during late gestation. Biomechanical forces play a critical role in the normal morphogenesis of most tissues. The magnitude and direction of force impact the form of the developing fetus, with a specific tissue response depending on its pliability and stage of development. Major uterine constraining factors include primigravida, small maternal size, uterine malformation, uterine fibromata, early pelvic engagement of the fetal head, aberrant fetal position, oligohydramnios, and multifetal gestation. Corrective mechanical forces similar to those that gave rise to the deformation to reshape the deformed structures are often used and should take advantage of the rapid postnatal growth to correct form. PMID:22888434

  5. Therapeutic Targeting of Fibroblast Growth Factor Receptors in Gastric Cancer

    PubMed Central

    Fujimori, Yoshitaka; Otsuki, Sho; Sato, Yuya; Nakagawa, Masatoshi

    2015-01-01

    Chemotherapy has become the global standard treatment for patients with metastatic or unresectable gastric cancer (GC), although outcomes remain unfavorable. Many molecular-targeted therapies inhibiting signaling pathways of various tyrosine kinase receptors have been developed, and monoclonal antibodies targeting human epidermal growth factor receptor 2 (HER2) have become standard therapy for HER2-positive GC. An inhibitor of vascular endothelial growth factor receptor 2 or MET has also produced promising results in patients with GC. Fibroblast growth factor receptors (FGFR) play key roles in tumor growth via activated signaling pathways in GC. Genomic amplification of FGFR2 leads to the aberrant activation found in GC tumors and is related to survival in patients with GC. This review discusses the clinical relevance of FGFR in GC and examines FGFR as a potential therapeutic target in patients with GC. Preclinical studies in animal models suggest that multitargeted tyrosine kinase inhibitors (TKIs), including FGFR inhibitor, suppress tumor cell proliferation and delay tumor progression. Several TKIs are now being evaluated in clinical trials as treatment for metastatic or unresectable GC harboring FGFR2 amplification. PMID:26000013

  6. Vascular growth factors and receptors in capillary hemangioblastomas and hemangiopericytomas.

    PubMed Central

    Hatva, E.; Böhling, T.; Jääskeläinen, J.; Persico, M. G.; Haltia, M.; Alitalo, K.

    1996-01-01

    Capillary hemangioblastomas and hemangiopericytomas are highly vascular central nervous system tumors of controversial origin. Of interest in their pathogenesis are mechanisms regulating endothelial cell growth. The endothelial cell mitogen vascular endothelial growth factor (VEGF) stimulates angiogenesis, and together with its two receptor tyrosine kinases VEGFR-1(FLT1) and VEGFR-2(KDR), is up-regulated during the malignant progression of gliomas. We have analyzed the expression of VEGF and its receptors, the related placental growth factor (PlGF) and the endothelial receptors FLT4 and Tie by in situ hybridization in capillary hemangioblastomas and hemangiopericytomas. VEGF mRNA was up-regulated in all of the hemangiopericytomas studied and highly expressed in the stromal cells of hemangioblastomas. In addition, some hemangioblastoma tumor cells expressed high levels of PlGF. Significantly elevated levels of Tie mRNA, Tie protein, VEGFR-1, and VEGFR-2 but not FLT4 mRNAs were observed in the endothelia of both tumor types. In hemangioblastomas, however, the receptors were also highly expressed by a subpopulation of stromal cells. Consistent results were obtained for a human hemangioblastoma cell line in culture. Up-regulation of the endothelial growth factors and receptors may result in autocrine or paracrine stimulation of endothelial cells and their precursors involved in the genesis of these two vascular tumors. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:8774132

  7. Transforming growth factor (TGF)-. alpha. in human milk

    SciTech Connect

    Okada, Masaki; Wakai, Kae; Shizume, Kazuo ); Iwashita, Mitsutoshi ); 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.

  8. Therapeutic targeting of fibroblast growth factor receptors in gastric cancer.

    PubMed

    Inokuchi, Mikito; Fujimori, Yoshitaka; Otsuki, Sho; Sato, Yuya; Nakagawa, Masatoshi; Kojima, Kazuyuki

    2015-01-01

    Chemotherapy has become the global standard treatment for patients with metastatic or unresectable gastric cancer (GC), although outcomes remain unfavorable. Many molecular-targeted therapies inhibiting signaling pathways of various tyrosine kinase receptors have been developed, and monoclonal antibodies targeting human epidermal growth factor receptor 2 (HER2) have become standard therapy for HER2-positive GC. An inhibitor of vascular endothelial growth factor receptor 2 or MET has also produced promising results in patients with GC. Fibroblast growth factor receptors (FGFR) play key roles in tumor growth via activated signaling pathways in GC. Genomic amplification of FGFR2 leads to the aberrant activation found in GC tumors and is related to survival in patients with GC. This review discusses the clinical relevance of FGFR in GC and examines FGFR as a potential therapeutic target in patients with GC. Preclinical studies in animal models suggest that multitargeted tyrosine kinase inhibitors (TKIs), including FGFR inhibitor, suppress tumor cell proliferation and delay tumor progression. Several TKIs are now being evaluated in clinical trials as treatment for metastatic or unresectable GC harboring FGFR2 amplification. PMID:26000013

  9. 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

  10. Novel therapeutic strategies for acute lung injury induced by lung damaging agents: the potential role of growth factors as treatment options.

    PubMed

    Lindsay, Christopher D

    2011-07-01

    The increasing threat from terrorism has brought attention to the possible use of toxic industrial compounds (TICs) and other lung-damaging agents as weapons against civilian populations. The way in which these agents could be used favours the development of generic countermeasures. Improved medical countermeasures would increase survivability and improve the quality of recovery of lung damaged casualties. It is evident that there is a dearth of therapeutic regimes available to treat those forms of lung damage that currently require intensive care management. It is quite possible that mass casualties from a terrorist incident or major industrial accident involving the release of large quantities of inhaled TICs would place a severe burden on already scarce intensive care facilities. The development of effective pharmacological approaches to assist the recovery of casualties suffering from acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) may improve the prognosis of such patients (which is currently poor) and would ideally be used as a means of preventing subjects from developing the pulmonary oedema characteristic of ALI/ARDS. Many promising candidate pharmacological treatments have been evaluated for the treatment of ALI/ARDS, but their clinical value is often debatable. Thus, despite improvements in ventilation strategies, pharmacological intervention for ALI/ARDS remains problematical. A new approach is clearly required for the treatment of patients with severely compromised lungs. Whilst the pathology of ALI/ARDS associated with exposure to a variety of agents is complex, numerous experimental studies suggest that generic therapeutic intervention directed at approaches that aim to upregulate repair of the damaged alveolar blood/air barrier of the lung may be of value, particularly with respect to chemical-induced injury. To this end, keratinocyte growth factor (KGF), epithelial growth factor (EGF) and basic fibroblast growth factor (bFGF) are emerging as the most important candidates. Hepatocyte growth factor (HGF) does not have epithelial specificity for lung tissue. However, the enhanced effects of combinations of growth factors, such as the synergistic effect of HGF upon vascular endothelial growth factor (VEGF)-mediated endothelial cell activity, and the combined effect of HGF and KGF in tissue repair should be investigated, particularly as the latter pair of growth factors are frequently implicated in processes associated with the repair of lung damage. Synergistic interactions also occur between trefoil factor family (TFF) peptides and growth factors such as EGF. TFF peptides are most likely to be of value as a short term therapeutic intervention strategy in stimulating epithelial spreading activities which allow damaged mucosal surfaces to be rapidly covered by epithelial cells. PMID:20621953

  11. Lifetime growth in wild meerkats: incorporating life history and environmental factors into a standard growth model.

    PubMed

    English, Sinéad; Bateman, Andrew W; Clutton-Brock, Tim H

    2012-05-01

    Lifetime records of changes in individual size or mass in wild animals are scarce and, as such, few studies have attempted to model variation in these traits across the lifespan or to assess the factors that affect them. However, quantifying lifetime growth is essential for understanding trade-offs between growth and other life history parameters, such as reproductive performance or survival. Here, we used model selection based on information theory to measure changes in body mass over the lifespan of wild meerkats, and compared the relative fits of several standard growth models (monomolecular, von Bertalanffy, Gompertz, logistic and Richards). We found that meerkats exhibit monomolecular growth, with the best model incorporating separate growth rates before and after nutritional independence, as well as effects of season and total rainfall in the previous nine months. Our study demonstrates how simple growth curves may be improved by considering life history and environmental factors, which may be particularly relevant when quantifying growth patterns in wild populations. PMID:22108854

  12. Growth factors induce actin disruption in cultured human retinal pigment epithelial cells.

    PubMed

    Shirakawa, H; Yoshimura, N; Ogino, N

    1986-01-01

    Exposure of cultured human retinal pigment epithelial cells to platelet-derived growth factor, nerve growth factor or epidermal growth factor resulted in a time- and dose-dependent alteration in the distribution of actin stained by rhodamine-phalloidin. These growth factors (platelet-derived growth factor of 80 ng/ml, nerve growth factor of 10 ng/ml or epidermal growth factor of 10 ng/ml) caused disappearance of actin filaments from the peripheral region of a cell in 1 or 2 h and change of cell configuration to spindle shape in 3 or 4 h. Other growth factors, fibroblast growth factor of 10 ng/ml and insulin of 25 mumol/ml had no effect on actin distribution. The alteration of actin and the change of cellular shape might be associated with stimulation of cell growth and migration of retinal pigment epithelial cells. PMID:3496571

  13. 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

  14. 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

    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

  15. Growth factor choice is critical for successful functionalization of nanoparticles

    PubMed Central

    Pinkernelle, Josephine; Raffa, Vittoria; Calatayud, Maria P.; Goya, Gerado F.; Riggio, Cristina; Keilhoff, Gerburg

    2015-01-01

    Nanoparticles (NPs) show new characteristics compared to the corresponding bulk material. These nanoscale properties make them interesting for various applications in biomedicine and life sciences. One field of application is the use of magnetic NPs to support regeneration in the nervous system. Drug delivery requires a functionalization of NPs with bio-functional molecules. In our study, we functionalized self-made PEI-coated iron oxide NPs with nerve growth factor (NGF) and glial cell-line derived neurotrophic factor (GDNF). Next, we tested the bio-functionality of NGF in a rat pheochromocytoma cell line (PC12) and the bio-functionality of GDNF in an organotypic spinal cord culture. Covalent binding of NGF to PEI-NPs impaired bio-functionality of NGF, but non-covalent approach differentiated PC12 cells reliably. Non-covalent binding of GDNF showed a satisfying bio-functionality of GDNF:PEI-NPs, but turned out to be unstable in conjugation to the PEI-NPs. Taken together, our study showed the importance of assessing bio-functionality and binding stability of functionalized growth factors using proper biological models. It also shows that successful functionalization of magnetic NPs with growth factors is dependent on the used binding chemistry and that it is hardly predictable. For use as therapeutics, functionalization strategies have to be reproducible and future studies are needed. PMID:26388717

  16. Localisation of placenta growth factor (PIGF) in human term placenta.

    PubMed

    Khaliq, A; Li, X F; Shams, M; Sisi, P; Acevedo, C A; Whittle, M J; Weich, H; Ahmed, A

    1996-01-01

    Placenta growth factor (PlGF) is a growth factor which belongs to the vascular endothelial growth factor (VEGF) family and is known to bind to the fms-like tyrosine kinase receptor (flt-1). Using Western blot analysis a 50 kDa band was identified in placental protein extract which corresponded to PlGF homodimer. Immunoreactive PlGF was localised to the vasculosyncytial membrane and in the media of large blood vessels of the placental villi, while staining within the mesenchyme was weak and diffuse. There was moderate staining for PlGF in discrete cells in the chorion and no staining in the epithelial layer of the amnion. The maternal decidual cells showed strong staining for PlGF immunoreactive protein. PlGF mRNA was predominantly expressed by the vasculosyncytial membrane of villous trophoblast, whilst there was no apparent expression of PlGF mRNA within the villous mesenchyme. These results suggest that PlGF may be an important paracrine factor for vascular endothelial cells in placental angiogenesis and an autocrine mediator of trophoblast function. PMID:8919031

  17. Nerve Growth Factor and Vascular Endothelial Growth Factor: Retrospective Analysis of 63 Patients with Salivary Adenoid Cystic Carcinoma

    PubMed Central

    Li, Hao; Nong, Xiao-lin; Chen, Qi; Yang, Yi-ping; Li, Jia-quan; Li, Yan-ning

    2010-01-01

    Aim To detect the expression of nerve growth factor (NGF) and vascular endothelial growth factor (VEGF) in salivary adenoid cystic carcinoma (SACC) tissues, as well as to determine the correlation between growth factor expression and prognosis in SACC. Methodology Medical records of 63 patients surgically treated for SACC between January 1988 and October 2005 were reviewed. Immunohistochemistry was performed to examine the expression of NGF and VEGF in tumor tissues. Kaplan-Meier analysis and Cox's proportional hazard regression model were applied to assess predictors of survival. Results NGF and VEGF were overexpressed in SACC tissues, compared with those in normal salivary tissues (P<0.05), and the staining intensity of these two factors was stronger in groups of solid subtype, advanced TNM stage, perineural invasion and recurrence. Patients with high-expression of NGF and VEGF, solid subtype, advanced stage, perineural invasion, recurrence and extended resection alone had worse survival rates (P<0.05). Conclusion NGF and VEGF are expressed increasingly in the tissues of SACC cases with invasion and metastasis. NGF expression and VEGF expression are independent prognosis factors for survival. PMID:20690417

  18. Critical growth factors and signalling pathways controlling human trophoblast invasion

    PubMed Central

    KNÖFLER, MARTIN

    2010-01-01

    Invasion of placental trophoblasts into uterine tissue and vessels is an essential process of human pregnancy and fetal development. Due to their remarkable plasticity invasive trophoblasts fulfil numerous functions, i.e. anchorage of the placenta, secretion of hormones, modulation of decidual angiogenesis/lymphangiogenesis and remodelling of maternal spiral arteries. The latter is required to increase blood flow to the placenta, thereby ensuring appropriate transfer of nutrients and oxygen to the developing fetus. Since failures in vascular changes of the placental bed are associated with pregnancy diseases such as preeclampsia or intrauterine growth restriction, basic research in this particular field focuses on molecular mechanisms controlling trophoblast invasion under physiological and pathological conditions. Throughout the years, an increasing number of growth factors, cytokines and angiogenic molecules controlling trophoblast motility have been identified. These factors are secreted from numerous cells such as trophoblast, maternal epithelial and stromal cells, as well as uterine NK cells and macrophages, suggesting that a complex network of cell types, mediators and signalling pathways regulates trophoblast invasiveness. Whereas essential features of the invasive trophoblast such as expression of critical proteases and adhesion molecules have been well characterised, the interplay between different cell types and growth factors and the cross-talk between distinct signalling cascades remain largely elusive. Similarly, key-regulatory transcription factors committing and differentiating invasive trophoblasts are mostly unknown. This review will summarise our current understanding of growth factors and signal transduction pathways regulating human trophoblast invasion/migration, as well as give insights into novel mechanisms involved in the particular differentiation process. PMID:19876833

  19. MiR-146a negatively regulates TLR2-induced inflammatory responses in keratinocytes.

    PubMed

    Meisgen, Florian; Xu Landén, Ning; Wang, Aoxue; Réthi, Bence; Bouez, Charbel; Zuccolo, Michela; Gueniche, Audrey; Ståhle, Mona; Sonkoly, Enikö; Breton, Lionel; Pivarcsi, Andor

    2014-07-01

    Keratinocytes represent the first line of defense against pathogens in the skin and have important roles in initiating and regulating inflammation during infection and autoimmunity. Here we investigated the role of miR-146a in the regulation of the innate immune response of keratinocytes. Toll-like receptor 2 (TLR2) stimulation of primary human keratinocytes resulted in an NF-?B- and mitogen-activated protein kinase-dependent upregulation of miR-146a expression, which was surprisingly long lasting, contrasting with the rapid and transient induction of inflammatory mediators. Overexpression of miR-146a significantly suppressed the production of IL-8, CCL20, and tumor necrosis factor-?, which functionally suppressed the chemotactic attraction of neutrophils by keratinocytes. Inhibition of endogenous miR-146a induced the production of inflammatory mediators even in nonstimulated keratinocytes, and potentiated the effect of TLR2 stimulation. Transcriptomic profiling revealed that miR-146a suppresses the expression of a large number of immune-related genes in keratinocytes. MiR-146a downregulated interleukin-1 receptor-associated kinase 1 and TNF receptor-associated factor 6, two key adapter molecules downstream of TLR signaling, and suppressed NF-?B promoter-binding activity as shown by promoter luciferase experiments. Together, these data identify miR-146a as a regulatory element in keratinocyte innate immunity, which prevents the production of inflammatory mediators under homeostatic conditions and serves as a potent negative feedback regulator after TLR2 stimulation. PMID:24670381

  20. Nrf2 Regulates the Sensitivity of Mouse Keratinocytes to Nitrogen Mustard via Multidrug Resistance-Associated Protein 1 (Mrp1).

    PubMed

    Udasin, Ronald G; Wen, Xia; Bircsak, Kristin M; Aleksunes, Lauren M; Shakarjian, Michael P; Kong, Ah-Ng Tony; Heck, Diane E; Laskin, Debra L; Laskin, Jeffrey D

    2016-01-01

    Sulfur mustard and nitrogen mustard (mechlorethamine, HN2) are potent vesicants developed as chemical warfare agents. These electrophilic, bifunctional alkylating agents cause skin injury, including inflammation, edema, and blistering. HN2 covalently modifies macromolecules such as DNA, RNA, and proteins or is scavenged by glutathione, forming adducts that can contribute to toxicity. Multidrug resistance-associated protein 1 (Mrp1/MRP1) is a transmembrane ATPase known to efflux glutathione-conjugated electrophiles. In the present studies, we examined the effects of modulating Mrp1-mediated transport activity on the sensitivity of primary and PAM212 mouse keratinocytes to HN2. Primary keratinocytes, and to a lesser extent, PAM212 cells, express Mrp1 mRNA and protein and possess Mrp1 functional activity, as measured by calcein efflux. Sulforaphane, an activator of Nrf2, increased Mrp1 mRNA, protein, and functional activity in primary keratinocytes and PAM212 cells and decreased their sensitivity to HN2-induced growth inhibition (IC50?=?1.4 and 4.8?µM in primary keratinocytes and 1 and 13?µM in PAM212 cells, in the absence and presence of sulforaphane, respectively). The Mrp1 inhibitor, MK-571, reversed the effects of sulforaphane on HN2-induced growth inhibition in both primary keratinocytes and PAM212 cells. In primary keratinocytes from Nrf2(-/-) mice, sulforaphane had no impact on Mrp1 expression or activity, or on sensitivity to HN2, demonstrating that its effects depend on Nrf2. These data suggest that Mrp1-mediated efflux is important in regulating HN2-induced keratinocyte growth inhibition. Enhancing HN2 efflux from keratinocytes may represent a novel strategy for mitigating vesicant-induced cytotoxicity. PMID:26454883

  1. Cell type-dependent modulation of the gene encoding heat shock protein HSPA2 by hypoxia-inducible factor HIF-1: Down-regulation in keratinocytes and up-regulation in HeLa cells.

    PubMed

    Habryka, Anna; Gogler-Pig?owska, Agnieszka; Sojka, Damian; Kryj, Mariusz; Krawczyk, Zdzis?aw; Scieglinska, Dorota

    2015-09-01

    HSPA2 belongs to the multigene HSPA family, whose members encode chaperone proteins. Although expression and function of HSPA2 is mainly associated with spermatogenesis, recent studies demonstrated that in humans, the gene is active in various cancers, as well as in normal tissues, albeit in a cell type-specific manner. In the epidermis, HSPA2 is expressed in keratinocytes in the basal layer. Currently, the mechanisms underlying the regulation of HSPA2 expression remain unknown. This study was aimed at determining whether HIF-1 and its binding site, the hypoxia-response element (HRE) located in the HSPA2 promoter, are involved in HSPA2 regulation. As a model system, we used an immortal human keratinocyte line (HaCaT) and cervical cancer cells (HeLa) grown under control or hypoxic conditions. Using an in vitro gene reporter assay, we demonstrated that in keratinocytes HSPA2 promoter activity is reduced under conditions that facilitate stabilization of HIF-1?, whereas HIF-1 inhibitors abrogated the suppressive effect of hypoxia on promoter activity. Chromatin immunoprecipitation revealed that HIF-1? binds to the HSPA2 promoter. In keratinocytes, hypoxia or overexpression of a stable form of HIF-1? attenuated the expression of endogenous HSPA2, whereas targeted repression of HIF-1? by RNAi increased transcription of HSPA2 under hypoxia. Conversely, in HeLa cells, HSPA2 expression increased under conditions that stimulated HIF-1? activity, whereas inhibition of HIF-1? abrogated hypoxia-induced up-regulation of HSPA2 expression. Taken together, our results demonstrate that HIF-1 can exert differential, cell context-dependent regulatory control of the HSPA2 gene. Additionally, we also showed that HSPA2 expression can be stimulated during hypoxia/reoxygenation stress. PMID:26164067

  2. Blocking Fibroblast Growth Factor Receptor Signaling Inhibits Tumor Growth, Lymphangiogenesis, and Metastasis

    PubMed Central

    Larrieu-Lahargue, Frédéric; Welm, Alana L.; Bouchecareilh, Marion; Alitalo, Kari; Li, Dean Y.; Bikfalvi, Andreas; Auguste, Patrick

    2012-01-01

    Fibroblast Growth Factor receptor (FGFR) activity plays crucial roles in tumor growth and patient survival. However, FGF (Fibroblast Growth Factor) signaling as a target for cancer therapy has been under-investigated compared to other receptor tyrosine kinases. Here, we studied the effect of FGFR signaling inhibition on tumor growth, metastasis and lymphangiogenesis by expressing a dominant negative FGFR (FGFR-2DN) in an orthotopic mouse mammary 66c14 carcinoma model. We show that FGFR-2DN-expressing 66c14 cells proliferate in vitro slower than controls. 66c14 tumor outgrowth and lung metastatic foci are reduced in mice implanted with FGFR-2DN-expressing cells, which also exhibited better overall survival. We found 66c14 cells in the lumen of tumor lymphatic vessels and in lymph nodes. FGFR-2DN-expressing tumors exhibited a decrease in VEGFR-3 (Vascular Endothelial Growth Factor Receptor-3) or podoplanin-positive lymphatic vessels, an increase in isolated intratumoral lymphatic endothelial cells and a reduction in VEGF-C (Vascular Endothelial Growth Factor-C) mRNA expression. FGFs may act in an autocrine manner as the inhibition of FGFR signaling in tumor cells suppresses VEGF-C expression in a COX-2 (cyclooxygenase-2) or HIF1-? (hypoxia-inducible factor-1 ?) independent manner. FGFs may also act in a paracrine manner on tumor lymphatics by inducing expression of pro-lymphangiogenic molecules such as VEGFR-3, integrin ?9, prox1 and netrin-1. Finally, in vitro lymphangiogenesis is impeded in the presence of FGFR-2DN 66c14 cells. These data confirm that both FGF and VEGF signaling are necessary for the maintenance of vascular morphogenesis and provide evidence that targeting FGFR signaling may be an interesting approach to inhibit tumor lymphangiogenesis and metastatic spread. PMID:22761819

  3. Impact of epidermal growth factor receptor and transforming growth factor-? on hepatitis C virus-induced hepatocarcinogenesis.

    PubMed

    Badawy, Afkar Abdel-Ghany; El-Hindawi, Ali; Hammam, Olfat; Moussa, Mona; Gabal, Samia; Said, Noha

    2015-10-01

    Epidermal growth factor receptor system plays a central hepato-protective and pro-regenerative role in liver. Transforming growth factor-? (TGF-?) is an important autocrine growth regulator of hepatocytes that plays a role in development of hepatocellular carcinoma (HCC) among patients with chronic hepatitis C (CHC). This study was done on 40 core liver biopsies from patients with CHC, 20 liver specimens from HCC cases on top of CHC as well as five normal controls. All were immunohistochemically stained with epidermal growth factor receptor (EGFR) and TGF-? antibodies. Some selected HCC cases were submitted for FISH technique to detect EGFR gene alteration. By immunohistochemistry EGFR and TGF-? were overexpressed in HCC and cirrhotic cases compared to CHC cases without cirrhosis. Also, their expression was stronger in CHC cases with higher grades of activity and stages of fibrosis compared to lower ones. FISH positive results for EGFR were detected in 33.3% of the examined HCC cases. EGFR and TGF-? can be used as predictive markers for activity, fibrosis, and carcinogenesis in CHC patients. Overexpression of EGFR in HCC patients can be promising in selecting those who can get benefit from anti-EGFR target therapy. PMID:26279457

  4. Antitumor effect of hepatocyte growth factor on hepatoblastoma.

    PubMed

    Tsunoda, Y; Shibusawa, M; Tsunoda, A; Gomi, A; Yatsuzuka, M; Okamatsu, T

    1998-01-01

    A six month-old girl presented with an abdominal mass, and high serum level of alpha-fetoprotein. She was diagnosed as having a well-differentiated hepatoblastoma by open biopsy. The biopsy specimen was transplanted on a nude mouse, and a xenograft was successfully established. Because the xenograft maintained the characteristics of the original tumor, the effect of hepatocyte growth factor (HGF) on hepatoblastoma xenograft was investigated. Recently HGF was reported to be involved in growth, invasion, and metastasis of tumor cells. Contrary to our expectations, the treatment of hepatoblastoma xenograft with recombinant 20 ng/ml HGF produced a marked inhibition of cell growth and a suppression of producing alpha-fetoprotein. PMID:9891489

  5. 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.

  6. Temporins A and B stimulate migration of HaCaT keratinocytes and kill intracellular Staphylococcus aureus.

    PubMed

    Di Grazia, Antonio; Luca, Vincenzo; Segev-Zarko, Li-Av T; Shai, Yechiel; Mangoni, Maria Luisa

    2014-05-01

    The growing number of microbial pathogens resistant to available antibiotics is a serious threat to human life. Among them is the bacterium Staphylococcus aureus, which colonizes keratinocytes, the most abundant cell type in the epidermis. Its intracellular accumulation complicates treatments against resulting infections, mainly due to the limited diffusion of conventional drugs into the cells. Temporins A (Ta) and B (Tb) are short frog skin antimicrobial peptides (AMPs). Despite extensive studies regarding their antimicrobial activity, very little is known about their activity on infected cells or involvement in various immunomodulatory functions. Here we show that Tb kills both ATCC-derived and multidrug-resistant clinical isolates of S. aureus within infected HaCaT keratinocytes (80% and 40% bacterial mortality, respectively) at a nontoxic concentration, i.e., 16 ?M, whereas a weaker effect is displayed by Ta. Furthermore, the peptides prevent killing of keratinocytes by the invading bacteria. Further studies revealed that both temporins promote wound healing in a monolayer of HaCaT cells, with front speed migrations of 19 ?m/h and 12 ?m/h for Ta and Tb, respectively. Migration is inhibited by mitomycin C and involves the epidermal growth factor receptor (EGFR) signaling pathway. Finally, confocal fluorescence microscopy indicated that the peptides diffuse into the cells. By combining antibacterial and wound-healing activities, Ta and Tb may act as multifunctional mediators of innate immunity in humans. Particularly, their nonendogenous origin may reduce microbial resistance to them as well as the risk of autoimmune diseases in mammals. PMID:24514087

  7. Temporins A and B Stimulate Migration of HaCaT Keratinocytes and Kill Intracellular Staphylococcus aureus

    PubMed Central

    Di Grazia, Antonio; Luca, Vincenzo; Segev-Zarko, Li-av T.; Shai, Yechiel

    2014-01-01

    The growing number of microbial pathogens resistant to available antibiotics is a serious threat to human life. Among them is the bacterium Staphylococcus aureus, which colonizes keratinocytes, the most abundant cell type in the epidermis. Its intracellular accumulation complicates treatments against resulting infections, mainly due to the limited diffusion of conventional drugs into the cells. Temporins A (Ta) and B (Tb) are short frog skin antimicrobial peptides (AMPs). Despite extensive studies regarding their antimicrobial activity, very little is known about their activity on infected cells or involvement in various immunomodulatory functions. Here we show that Tb kills both ATCC-derived and multidrug-resistant clinical isolates of S. aureus within infected HaCaT keratinocytes (80% and 40% bacterial mortality, respectively) at a nontoxic concentration, i.e., 16 ?M, whereas a weaker effect is displayed by Ta. Furthermore, the peptides prevent killing of keratinocytes by the invading bacteria. Further studies revealed that both temporins promote wound healing in a monolayer of HaCaT cells, with front speed migrations of 19 ?m/h and 12 ?m/h for Ta and Tb, respectively. Migration is inhibited by mitomycin C and involves the epidermal growth factor receptor (EGFR) signaling pathway. Finally, confocal fluorescence microscopy indicated that the peptides diffuse into the cells. By combining antibacterial and wound-healing activities, Ta and Tb may act as multifunctional mediators of innate immunity in humans. Particularly, their nonendogenous origin may reduce microbial resistance to them as well as the risk of autoimmune diseases in mammals. PMID:24514087

  8. Lipid Rafts and Caveolae in Signaling by Growth Factor Receptors

    PubMed Central

    de Laurentiis, Angela; Donovan, Lorna; Arcaro, Alexandre

    2007-01-01

    Lipid rafts and caveolae are microdomains of the plasma membrane enriched in sphingolipids and cholesterol, and hence are less fluid than the remainder of the membrane. Caveolae have an invaginated structure, while lipid rafts are flat regions of the membrane. The two types of microdomains have different protein compositions (growth factor receptors and their downstream molecules) suggesting that lipid rafts and caveolae have a role in the regulation of signaling by these receptors. The purpose of this review is to discuss this model, and the implications that it might have regarding a potential role for lipid rafts and caveolae in human cancer. Particular attention will be paid to the epidermal growth factor receptor, for which the largest amount of information is available. It has been proposed that caveolins act as tumor suppressors. The role of lipid rafts is less clear, but they seem to be capable of acting as ‘signaling platforms’, in which signal initiation and propagation can occur efficiently. PMID:18949068

  9. Hepatocyte growth factor: A regulator of inflammation and autoimmunity.

    PubMed

    Molnarfi, Nicolas; Benkhoucha, Mahdia; Funakoshi, Hiroshi; Nakamura, Toshikazu; Lalive, Patrice H

    2015-04-01

    Hepatocyte growth factor (HGF) is a pleiotropic cytokine that has been extensively studied over several decades, but was only recently recognized as a key player in mediating protection of many types of inflammatory and autoimmune diseases. HGF was reported to prevent and attenuate disease progression by influencing multiple pathophysiological processes involved in inflammatory and immune response, including cell migration, maturation, cytokine production, antigen presentation, and T cell effector function. In this review, we discuss the actions and mechanisms of HGF in inflammation and immunity and the therapeutic potential of this factor for the treatment of inflammatory and autoimmune diseases. PMID:25476732

  10. Harnessing endogenous growth factor activity modulates stem cell behavior

    PubMed Central

    Hudalla, Gregory A.; Kouris, Nicholas A.; Koepsel, Justin T.; Ogle, Brenda M.; Murphy, William L.

    2014-01-01

    The influence of specific serum-borne biomolecules (e.g. heparin) on growth factor-dependent cell behavior is often difficult to elucidate in traditional cell culture due to the random, non-specific nature of biomolecule adsorption from serum. We hypothesized that chemically well-defined cell culture substrates could be used to study the influence of sequestered heparin on human mesenchymal stem cell (hMSC) behavior. Specifically, we used bio-inert self-assembled monolayers (SAMs) chemically modified with a bioinspired heparin-binding peptide (termed “HEPpep”) and an integrin-binding peptide (RGDSP) as stem cell culture substrates. Our results demonstrate that purified heparin binds to HEPpep SAMs in a dose-dependent manner, and serum-borne heparin binds specifically and in a dose-dependent manner to HEPpep SAMs. These heparin-sequestering SAMs enhance hMSC proliferation by amplifying endogenous fibroblast growth factor (FGF) signaling, and enhance hMSC osteogenic differentiation by amplifying endogenous bone morphogenetic protein (BMP) signaling. The effects of heparin-sequestering are similar to the effects of supraphysiologic concentrations of recombinant FGF-2. hMSC phenotype is maintained over multiple population doublings on heparin-sequestering substrates in growth medium, while hMSC osteogenic differentiation is enhanced in a bone morphogenetic protein-dependent manner on the same substrates during culture in osteogenic induction medium. Together, these observations demonstrate that the influence of the substrate on stem cell phenotype is sensitive to the culture medium formulation. Our results also demonstrate that enhanced hMSC proliferation can be spatially localized by patterning the location of HEPpep on the substrate. Importantly, the use of chemically well-defined SAMs in this study eliminated the confounding factor of random, non-specific biomolecule adsorption, and identified serum-borne heparin as a key mediator of hMSC response to endogenous growth factors. PMID:21720642

  11. Cytokines and growth factors cross-link heparan sulfate

    PubMed Central

    Migliorini, Elisa; Thakar, Dhruv; Kühnle, Jens; Sadir, Rabia; Dyer, Douglas P.; Li, Yong; Sun, Changye; Volkman, Brian F.; Handel, Tracy M.; Coche-Guerente, Liliane; Fernig, David G.; Lortat-Jacob, Hugues; Richter, Ralf P.

    2015-01-01

    The glycosaminoglycan heparan sulfate (HS), present at the surface of most cells and ubiquitous in extracellular matrix, binds many soluble extracellular signalling molecules such as chemokines and growth factors, and regulates their transport and effector functions. It is, however, unknown whether upon binding HS these proteins can affect the long-range structure of HS. To test this idea, we interrogated a supramolecular model system, in which HS chains grafted to streptavidin-functionalized oligoethylene glycol monolayers or supported lipid bilayers mimic the HS-rich pericellular or extracellular matrix, with the biophysical techniques quartz crystal microbalance (QCM-D) and fluorescence recovery after photobleaching (FRAP). We were able to control and characterize the supramolecular presentation of HS chains—their local density, orientation, conformation and lateral mobility—and their interaction with proteins. The chemokine CXCL12? (or SDF-1?) rigidified the HS film, and this effect was due to protein-mediated cross-linking of HS chains. Complementary measurements with CXCL12? mutants and the CXCL12? isoform provided insight into the molecular mechanism underlying cross-linking. Fibroblast growth factor 2 (FGF-2), which has three HS binding sites, was also found to cross-link HS, but FGF-9, which has just one binding site, did not. Based on these data, we propose that the ability to cross-link HS is a generic feature of many cytokines and growth factors, which depends on the architecture of their HS binding sites. The ability to change matrix organization and physico-chemical properties (e.g. permeability and rigidification) implies that the functions of cytokines and growth factors may not simply be confined to the activation of cognate cellular receptors. PMID:26269427

  12. Growth factors and their impact on transfusion medicine.

    PubMed

    Miller, Y M; Klein, H G

    1996-01-01

    Hematopoietic growth factors, glycoproteins that stimulate self-renewal, differentiation, and proliferation of responsive hematopoietic cells, promise to revolutionize transfusion medicine. Recombinant DNA technology has made several of these cytokines available at pharmacologic doses, and new candidate agents for clinical application appear regularly. Growth factors prescribed for patients have already reduced the requirement for red blood cell and granulocyte transfusions in selected clinical circumstances. A lineage-specific thrombopoietin will likely limit the need for platelet transfusions. Hematopoietic cytokine injections have also been used to increase the number of red blood cells, granulocytes and circulating primitive progenitor cells in blood donors. Cytokine-stimulated peripheral blood progenitor cell infusions have complemented and, in some instances, replaced bone marrow for adjunctive cancer chemotherapy and for bone marrow transplantation. Finally, synergistic combinations of cytokines can effect ex vivo expansion of lymphocytes and of progenitor cells to provide novel blood components. Hematopoietic growth factors are still expensive and their long-term effects remain to be determined. However, as the biologic activities of cytokines and the physiology of hematopoietic progenitor cells become better understood, the clinical application of novel cellular components may redefine the concept of blood transfusion. PMID:8958642

  13. Fibroblast growth factor receptor signaling crosstalk in skeletogenesis.

    PubMed

    Miraoui, Hichem; Marie, Pierre J

    2010-01-01

    Fibroblast growth factors (FGFs) play important roles in the control of embryonic and postnatal skeletal development by activating signaling through FGF receptors (FGFRs). Germline gain-of-function mutations in FGFR constitutively activate FGFR signaling, causing chondrocyte and osteoblast dysfunctions that result in skeletal dysplasias. Crosstalk between the FGFR pathway and other signaling cascades controls skeletal precursor cell differentiation. Genetic analyses revealed that the interplay of WNT and FGFR1 determines the fate and differentiation of mesenchymal stem cells during mouse craniofacial skeletogenesis. Additionally, interactions between FGFR signaling and other receptor tyrosine kinase networks, such as those mediated by the epidermal growth factor receptor and platelet-derived growth factor receptor ?, were associated with excessive osteoblast differentiation and bone formation in the human skeletal dysplasia called craniosynostosis, which is a disorder of skull development. We review the roles of FGFR signaling and its crosstalk with other pathways in controlling skeletal cell fate and discuss how this crosstalk could be pharmacologically targeted to correct the abnormal cell phenotype in skeletal dysplasias caused by aberrant FGFR signaling. PMID:21045207

  14. Effects of low frequency pulsed electrical current on keratinocytes in vitro

    SciTech Connect

    Hinsenkamp, M.; Jercinovic, A.

    1997-05-01

    The effects of low frequency pulsed electrical current on epidermal repair in vitro were examined. Charge-balanced current stimuli proposed for chronic wound treatment were tested on skin keratinocytes cultured at an air-liquid interface on dead human dermis. Results imply that the balance between proliferation and differentiation in electrically treated samples is significantly modified in favor of differentiation. More advanced differentiation, shown through epidermal histology, was obtained in cultures exposed to electrical current, whereas the culture growth, the result of keratinocyte migration and proliferation, was greater in control samples.

  15. KLF10, transforming growth factor-{beta}-inducible early gene 1, acts as a tumor suppressor

    SciTech Connect

    Song, Ki-Duk; Laboratory of Protein Engineering and Comparative Immunology, School of Agricultural Biotechnology, Seoul National University, Seoul 151-921 ; Kim, Duk-Jung; Lee, Jong Eun; Yun, Cheol-Heui; Laboratory of Protein Engineering and Comparative Immunology, School of Agricultural Biotechnology, Seoul National University, Seoul 151-921 ; Lee, Woon Kyu

    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.

  16. Eicosanoids and Keratinocytes in Wound Healing

    PubMed Central

    Sivamani, Raja K.

    2014-01-01

    Significance: Eicosanoids are biologically active lipid mediators derived from arachidonic acid that are important in injury and inflammatory responses. Cyclooxygenase-1 and cyclooxygenase-2 mediate the production of prostanoids, whereas 5-lipoxygenase mediates the production of leukotrienes and hydroxyeicosatetraenoic acids. These lipid mediators have traditionally been known to recruit cells of the immune system to a site of injury and inflammation. However, they also interact with various cells that are resident to the wound bed, including modulation of keratinocyte activity. Recent Advances: Recent work has identified multiple prostanoid and leukotriene receptors on keratinocytes, indicating that eicosanoids directly interact with them. Recent work also shows that keratinocytes are capable of producing prostanoids and leukotrienes. Critical Issues: Much of the critical work has been performed in cell culture and mouse in vivo models. This has greatly expanded our understanding of the eicosanoid interactions with keratinocytes and wound healing in general. However, few of these in vivo models have been able to critically evaluate keratinocyte migration and re-epithelialization. Future Directions: As research continues in this exciting field, the cellular pathways stimulated by the eicosanoids will become better defined. Future research with excisional wound models in mice and pigs and ex vivo human skin models will better isolate the contribution of eicosanoid-mediated effects on keratinocyte migration and re-epithelialization. PMID:25032067

  17. Enhancement of intestinal growth in neonatal rats by epidermal growth factor in milk

    SciTech Connect

    Berseth, C.L. )

    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.

  18. Glioblastoma cell growth is suppressed by disruption of Fibroblast Growth Factor pathway signaling.

    PubMed

    Loilome, Watcharin; Joshi, Avadhut D; ap Rhys, Colette M J; Piccirillo, Sara; Vescovi, Angelo L; Angelo, Vescovi L; Gallia, Gary L; Riggins, Gregory J

    2009-09-01

    The Fibroblast Growth Factor (FGF) signaling pathway is reported to stimulate glioblastoma (GBM) growth. In this work we evaluated the effect of FGF2, FGF receptor (FGFR), and small molecule inhibition on GBM cells grown in traditional media, or cultured directly in stem-cell media. These lines each expressed the FGFR1, FGFR3 and FGFR4 receptors. Addition of FGF2 ligand showed significant growth stimulation in 8 of 10 cell lines. Disruption of FGF signaling by a neutralizing FGF2 monoclonal antibody and FGFR1 suppression by RNA interference both partially inhibited cell proliferation. Growth inhibition was temporally correlated with a reduction in MAPK signaling. A receptor tyrosine kinase inhibitor with known FGFR/VEGFR activity, PD173074, showed reproducible growth inhibition. Possible mechanisms of growth suppression by PD173074 were implicated by reduced phosphorylation of AKT and MAPK, known oncogenic signal transducers. Subsequent reduction in the cyclin D1, cyclin D2 and CDK4 cell cycle regulators was also observed. Our results indicate that FGF signaling pathway inhibition as a monotherapy will slow, but not arrest growth of glioblastoma cells. PMID:19340397

  19. Selective Expression of Insulin-Like Growth Factor II in the Songbird Brain

    E-print Network

    Jarvis, Erich D.

    Selective Expression of Insulin-Like Growth Factor II in the Songbird Brain Martin Holzenberger,2 insulin-like growth factor II (IGF-II) cDNA, a factor known to regulate neu- ronal development; development; neuro- trophins; growth factors Discrete brain nuclei control the acquisition and production

  20. The role of peroxisome proliferator-activated receptor-{beta}/{delta} in epidermal growth factor-induced HaCaT cell proliferation

    SciTech Connect

    Liang Pengfei; Jiang Bimei; Yang Xinghua; Xiao Xianzhong Huang Xu; Long Jianhong; Zhang Pihong; Zhang Minghua; Xiao Muzhang; Xie Tinghong; Huang Xiaoyuan

    2008-10-15

    Epidermal growth factor (EGF) has been shown to be a potent mitogen for epidermal cells both in vitro and in vivo, thus contributing to the development of an organism. It has recently become clear that peroxisome proliferator-activated receptor-{beta}/{delta} (PPAR{beta}/{delta}) expression and activation is involved in the cell proliferation. However, little is known about the role of PPAR{beta}/{delta} in EGF-induced proliferation of HaCaT keratinocytes. In this study, HaCaT cells were cultured in the presence and absence of EGF and we identified that EGF induced an increase of PPAR{beta}/{delta} mRNA and protein level expression in time-dependent and dose-dependent manner, and AG1487, an EGF receptor (EGFR) special inhibitor, caused attenuation of PPAR{beta}/{delta} protein expression. Electrophoretic mobility shift assay (EMSA) revealed that EGF significantly increased PPAR{beta}/{delta} binding activity in HaCaT keratinocytes. Antisense phosphorothioate oligonucleotides (asODNs) against PPAR{beta}/{delta} caused selectively inhibition of PPAR{beta}/{delta} protein content induced by EGF and significantly attenuated EGF-mediated cell proliferation. Treatment of the cells with L165041, a specific synthetic ligand for PPAR{beta}/{delta}, significantly enhanced EGF-mediated cell proliferation. Finally, c-Jun ablation inhibited PPAR{beta}/{delta} up-regulation induced by EGF, and chromatin immunoprecipitation (ChIP) showed that c-Jun bound to the PPAR{beta}/{delta} promoter and the binding increased in EGF-stimulated cells. These results demonstrate that EGF induces PPAR{beta}/{delta} expression in a c-Jun-dependent manner and PPAR{beta}/{delta} plays a vital role in EGF-stimulated proliferation of HaCaT cells.

  1. Expression of transforming growth factor alpha and epidermal growth factor receptor in rat lung neoplasms induced by plutonium-239

    SciTech Connect

    Stegelmeier, B.L.; Gillett, N.A.; Hahn, F.F.; Kelly, G.; Rebar, A.H.

    1994-11-01

    Ninety-two rat lung proliferative lesions and neoplasms induced by inhaled {sup 239}PuO{sub 2} were evaluated for aberrant expression of transforming growth factor alpha (TGF-{alpha}) and epidermal growth factor receptor (EGFR). Expression of TGF-{alpha} protein, measured by immunohistochemistry, was higher in 94% of the squamous cell carcinomas and 87% of the foci of alveolar epithelial squamous metaplasia than that exhibited by the normal-appearing, adjacent lung parenchyma. In contrast, only 20% of adenocarcinomas and foci of epithelial hyperplasia expressed elevated levels of TGF-{alpha}. Many neoplasms expressing TGF-{alpha} also expressed excessive levels of EGFR mRNA. Southern and DNA slot blot analyses showed that the elevated EGFR expression was not due to amplification of the EGFR gene. These data suggest that increased amounts of TGF-{alpha} were early alterations in the progression of plutonium-induced squamous cell carcinoma, and these increases may occur in parallel with overexpression of the receptor for this growth factor. Together, these alterations create a potential autocrine loop for sustaining clonal expansion of cells initiated by high-LET radiation. 44 refs., 4 figs., 1 tab.

  2. Synergistic and multidimensional regulation of plasminogen activator inhibitor type 1 expression by transforming growth factor type ? and epidermal growth factor

    SciTech Connect

    Song, Xiaoling; Thalacker, F.W.; Nilsen-Hamilton, Marit

    2012-04-06

    The major physiological inhibitor of plasminogen activator, type I plasminogen activator inhibitor (PAI-1), controls blood clotting and tissue remodeling events that involve cell migration. Transforming growth factor type ? (TGF?) and epidermal growth factor (EGF) interact synergistically to increase PAI-1 mRNA and protein levels in human HepG2 and mink Mv1Lu cells. Other growth factors that activate tyrosine kinase receptors can substitute for EGF. EGF and TGF? regulate PAI-1 by synergistically activating transcription, which is further amplified by a decrease in the rate of mRNA degradation, the latter being regulated only by EGF. The combined effect of transcriptional activation and mRNA stabilization results in a rapid 2-order of magnitude increase in the level of PAI-1. TGF? also increases the sensitivity of the cells to EGF, thereby recruiting the cooperation of EGF at lower than normally effective concentrations. The contribution of EGF to the regulation of PAI-1 involves the MAPK pathway, and the synergistic interface with the TGF? pathway is downstream of MEK1/2 and involves phosphorylation of neither ERK1/2 nor Smad2/3. Synergism requires the presence of both Smad and AP-1 recognition sites in the promoter. This work demonstrates the existence of a multidimensional cellular mechanism by which EGF and TGF? are able to promote large and rapid changes in PAI-1 expression.

  3. Early exposure to ethanol or red wine and long-lasting effects in aged mice. A study on nerve growth factor, brain-derived neurotrophic factor, hepatocyte growth factor, and vascular endothelial growth factor.

    PubMed

    Ceccanti, Mauro; Mancinelli, Rosanna; Tirassa, Paola; Laviola, Giovanni; Rossi, Simona; Romeo, Marina; Fiore, Marco

    2012-02-01

    Prenatal ethanol exposure produces severe changes in brain, liver, and kidney through mechanisms involving growth factors. These molecules regulate survival, differentiation, maintenance, and connectivity of brain, liver, and kidney cells. Despite the abundant available data on the short and mid-lasting effects of ethanol intoxication, only few data show the long-lasting damage induced by early ethanol administration. The aim of this study was to investigate changes in nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), hepatocyte growth factor (HGF), and vascular endothelial growth factor (VEGF) in brain areas, liver, and kidney of 18-mo-old male mice exposed perinatally to ethanol at 11% vol or to red wine at the same ethanol concentration. The authors found that ethanol per se elevated NGF, BDNF, HGF, and VEGF measured by ELISA in brain limbic system areas. In the liver, early exposure to ethanol solution and red wine depleted BDNF and VEGF concentrations. In the kidney, red wine exposure only decreased VEGF. In conclusion, the present study shows that, in aged mice, early administration of ethanol solution induced long-lasting damage at growth factor levels in frontal cortex, hippocampus, and liver but not in kidney. Otherwise, in mice exposed to red wine, significant changes were observed in the liver and kidney but not in the hippocampus and frontal cortex. The brain differences in ethanol-induced toxicity when ethanol is administered alone or in red wine may be related to compounds with antioxidant properties present in the red wine. PMID:20382450

  4. Extracellular Matrix-Inspired Growth Factor Delivery Systems for Skin Wound Healing

    PubMed Central

    Briquez, Priscilla S.; Hubbell, Jeffrey A.; Martino, Mikaël M.

    2015-01-01

    Significance: Growth factors are very promising molecules for the treatment of skin wounds. However, their translation to clinical use has been seriously limited, facing issues related to safety and cost-effectiveness. These problems may derive from the fact that growth factors are used at vastly supra-physiological levels without optimized delivery systems. Recent Advances: The extracellular matrix (ECM) plays a fundamental role in coordinating growth factor signaling. Therefore, understanding the mechanisms by which the ECM modulates growth factor activity is key for designing efficient growth factor-based therapies. Recently, several growth factor-binding domains have been discovered within various ECM proteins, and growth factor delivery systems integrating these ECM growth factor-binding domains showed promising results in animal models of skin wound healing. Moreover, a novel strategy consisting of engineering growth factors to target endogenous ECM could substantially enhance their efficacy, even when used at low doses. Critical Issues: Optimal delivery of growth factors often requires complex engineered biomaterial matrices, which can face regulatory issues for clinical translation. To simplify delivery systems and render strategies more applicable, growth factors can be engineered to optimally function with clinically approved biomaterials or with endogenous ECM present at the delivery site. Future Directions: Further development and clinical trials will reveal whether growth factor-based therapies can be used as main therapeutic approaches for skin wound healing. The future impact of these therapies will depend on our capacity to deliver growth factors more precisely, to improve efficacy, safety, and cost-effectiveness. PMID:26244104

  5. Immortalized B lymphocytes produce B-cell growth factor.

    PubMed

    Gordon, J; Ley, S C; Melamed, M D; English, L S; Hughes-Jones, N C

    The activation, clonal expansion and terminal differentiation of small resting B lymphocytes primed by an antigen (or antibodies to its receptors) appear to follow an orderly developmental sequence triggered at each stage by distinct soluble cytokines, primarily produced by T lymphocytes. For man, the only known B-cell mitogen independent of accessory cells for its action is the Epstein-Barr virus (EBV). Lymphocytes transformed by EBV are released from the usual constraints on B-cell growth, proliferating continuously in the absence of any exogenous cytokine. The resultant cell lines are of special interest as they possess certain features compatible with a preneoplastic state of Burkitt's lymphoma, one of two human cancers with which the virus is intimately associated. We report here that following EBV-transformation, B lymphoblasts release a soluble factor which mimics the B-cell stimulatory product(s) of mitogen-conditioned T lymphocytes. Furthermore, the virally-transformed cells utilize this activity to sustain their own growth. The ectopic production of an otherwise normal growth factor may represent a critical event in the malignant evolution of human lymphomas harbouring the EBV genome. PMID:6610833

  6. 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

  7. 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

  8. 4-hydroxynonenal triggers an epidermal growth factor receptor-linked signal pathway for growth inhibition.

    PubMed

    Liu, W; Akhand, A A; Kato, M; Yokoyama, I; Miyata, T; Kurokawa, K; Uchida, K; Nakashima, I

    1999-07-01

    Lipid peroxidation has been implicated in the pathogenesis of various diseases. As a major product of membrane lipid peroxidation, 4-hydroxynonenal (HNE) appears after various kinds of oxidative stress, and is known to induce cell growth inhibition. We here analysed the HNE-mediated signal transduction cascade for the growth inhibition of human epidermoid carcinoma A431 cells. HNE dose-dependently induced phosphorylation of multiple cellular proteins including epidermal growth factor receptor (EGFR) in A431 cells, and rapidly upregulated the catalytic actions of EGFR for autophosphorylation and for phosphorylation of casein as an exogenous substrate. Immunoblot analysis by use of HNE-specific antibody demonstrated the binding of HNE to EGFR along with its activation. This binding, which did not induce cross-linking of EGFR, caused a capping of the receptor on the cell surface which mimicked the capping induced by EGF. Phosphorylation and activation of EGFR were followed by phosphorylation of adaptor protein Shc and activation of MAP kinase. Both genistein as a wide spectrum protein tyrosine kinase inhibitor and AG1478 as a specific EGFR tyrosine phosphorylation blocker inhibited activation of EGFR and MAP kinase by HNE. The same inhibitors prevented HNE-mediated growth inhibition, suggesting a close linkage between EGFR/MAP kinase activation and growth inhibition after exposure to HNE. Our results suggest that EGFR may be one of the primary targets of HNE for an oxidative stress-linked cell growth inhibition. PMID:10381396

  9. 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 ...

  10. Release characteristics of encapsulated formulations incorporating plant growth factors.

    PubMed

    Wybraniec, Slawomir; Schwartz, Liliana; Wiesman, Zeev; Markus, Arie; Wolf, David

    2002-05-01

    The release characteristics of encapsulated formulations containing a combination of plant growth factors (PGF)--plant hormones (IBA, paclobutrazol), nutrients (fertilizers, microelements), and fungicide (prochloraz)--were studied. The formulations were prepared by encapsulating the active ingredients in a polyethylene matrix and, in some cases, subsequently coating the product with polyurethane. Dissolution experiments were carried out with both coated and non-coated formulations to determine the sustained release patterns of the active ingredients. The PGF controlled-release systems obtained have been shown to promote development of root systems, vegetative growth, and reproductive development in cuttings, potted plants, or garden plants of various plant species. These beneficial effects are attributable to the lasting and balanced PGF availability provided by these systems. PMID:12009194

  11. Anti-Vascular Endothelial Growth Factor Therapy in Breast Cancer

    PubMed Central

    Kristensen, Tina Bøgelund; Knutsson, Malin L. T.; Wehland, Markus; Laursen, Britt Elmedal; Grimm, Daniela; Warnke, Elisabeth; Magnusson, Nils E.

    2014-01-01

    Neo-angiogenesis is a critical process for tumor growth and invasion and has become a promising target in cancer therapy. This manuscript reviews three currently relevant anti-angiogenic agents targeting the vascular endothelial growth factor system: bevacizumab, ramucirumab and sorafenib. The efficacy of anti-angiogenic drugs in adjuvant therapy or as neo-adjuvant treatment has been estimated in clinical trials of advanced breast cancer. To date, the overall observed clinical improvements are unconvincing, and further research is required to demonstrate the efficacy of anti-angiogenic drugs in breast cancer treatments. The outcomes of anti-angiogenic therapy have been highly variable in terms of tumor response. New methods are needed to identify patients who will benefit from this regimen. The development of biomarkers and molecular profiling are relevant research areas that may strengthen the ability to focus anti-angiogenic therapy towards suitable patients, thereby increase the cost-effectiveness, currently estimated to be inadequate. PMID:25514409

  12. The effects of growth factors on testicular germ cell apoptosis in the stallion 

    E-print Network

    Donnelly, Casey Leanne

    2002-01-01

    recombinant growth factors, stem cell factor (SCF), leukemia inhibiting factor (LIF), granulocyte macrophage-colony stimulating factor (GM-CSF), and one hormone, estradiol (E?), alone or in combination, to prevent apoptosis of germ cells in short-term equine...

  13. Eosinophil Cytokines, Chemokines, and Growth Factors: Emerging Roles in Immunity

    PubMed Central

    Davoine, Francis; Lacy, Paige

    2014-01-01

    Eosinophils derive from the bone marrow and circulate at low levels in the blood in healthy individuals. These granulated cells preferentially leave the circulation and marginate to tissues, where they are implicated in the regulation of innate and adaptive immunity. In diseases such as allergic inflammation, eosinophil numbers escalate markedly in the blood and tissues where inflammatory foci are located. Eosinophils possess a range of immunomodulatory factors that are released upon cell activation, including over 35 cytokines, growth factors, and chemokines. Unlike T and B cells, eosinophils can rapidly release cytokines within minutes in response to stimulation. While some cytokines are stored as pre-formed mediators in crystalloid granules and secretory vesicles, eosinophils are also capable of undergoing de novo synthesis and secretion of these immunological factors. Some of the molecular mechanisms that coordinate the final steps of cytokine secretion are hypothesized to involve binding of membrane fusion complexes comprised of soluble N-ethylmaleimide sensitive factor attachment protein receptors (SNAREs). These intracellular receptors regulate the release of granules and vesicles containing a range of secreted proteins, among which are cytokines and chemokines. Emerging evidence from both human and animal model-based research has suggested an active participation of eosinophils in several physiological/pathological processes such as immunomodulation and tissue remodeling. The observed eosinophil effector functions in health and disease implicate eosinophil cytokine secretion as a fundamental immunoregulatory process. The focus of this review is to describe the cytokines, growth factors, and chemokines that are elaborated by eosinophils, and to illustrate some of the intracellular events leading to the release of eosinophil-derived cytokines. PMID:25426119

  14. Integrated Functions of Transforming Growth Factor Beta, Latency Associated Peptide, and Integrins During Early Porcine Pregnancy 

    E-print Network

    Massuto, Dana A.

    2011-02-22

    . Integrins and growth factors are among many molecules likely involved in controlling implantation. Numerous integrins (ITG), including subunits ITGAV (alpha v), ITGB1 (beta 1), ITGB3 (beta 3), and ITGB5 (beta 5), and transforming growth factor betas (TGFBs...

  15. Tissue Engineering Using Transfected Growth-Factor Genes

    NASA Technical Reports Server (NTRS)

    Madry, Henning; Langer, Robert S.; Freed, Lisa E.; Trippel, Stephen; Vunjak-Novakovic, Gordana

    2005-01-01

    A method of growing bioengineered tissues includes, as a major component, the use of mammalian cells that have been transfected with genes for secretion of regulator and growth-factor substances. In a typical application, one either seeds the cells onto an artificial matrix made of a synthetic or natural biocompatible material, or else one cultures the cells until they secrete a desired amount of an extracellular matrix. If such a bioengineered tissue construct is to be used for surgical replacement of injured tissue, then the cells should preferably be the patient s own cells or, if not, at least cells matched to the patient s cells according to a human-leucocyteantigen (HLA) test. The bioengineered tissue construct is typically implanted in the patient's injured natural tissue, wherein the growth-factor genes enhance metabolic functions that promote the in vitro development of functional tissue constructs and their integration with native tissues. If the matrix is biodegradable, then one of the results of metabolism could be absorption of the matrix and replacement of the matrix with tissue formed at least partly by the transfected cells. The method was developed for articular chondrocytes but can (at least in principle) be extended to a variety of cell types and biocompatible matrix materials, including ones that have been exploited in prior tissue-engineering methods. Examples of cell types include chondrocytes, hepatocytes, islet cells, nerve cells, muscle cells, other organ cells, bone- and cartilage-forming cells, epithelial and endothelial cells, connective- tissue stem cells, mesodermal stem cells, and cells of the liver and the pancreas. Cells can be obtained from cell-line cultures, biopsies, and tissue banks. Genes, molecules, or nucleic acids that secrete factors that influence the growth of cells, the production of extracellular matrix material, and other cell functions can be inserted in cells by any of a variety of standard transfection techniques.

  16. 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.

  17. Muscle growth in young horses: Effects of age, cytokines, and growth factors.

    PubMed

    LaVigne, E K; Jones, A K; Londoño, A Sanchez; Schauer, A S; Patterson, D F; Nadeau, J A; Reed, S A

    2015-12-01

    Success as equine athletes requires proper muscle growth in young horses. Muscle hypertrophy occurs through protein synthesis and the contribution of muscle satellite cells, which can be stimulated or inhibited by cytokines and growth factors present during exercise and growth. The hypotheses of this study were that 1) the LM area in young horses would increase over 1 yr, and 2) specific cytokines and growth factors (IL-1?, IL-6, tumor necrosis factor [TNF]-?, IGF-I, and fibroblast growth factor [FGF]-2) would alter proliferation and differentiation of satellite cells isolated from young horses. Fourteen horses were divided into 3 age groups: weanlings ( = 5), yearlings to 2 yr olds ( = 4), and 3 to 4 yr olds ( = 5). The area, height, and subcutaneous fat depth of the LM were measured using ultrasonography, and BW and BCS were taken in October (Fall1), April (Spring), and October of the following year (Fall2). Satellite cells obtained from 10-d-old foals ( = 4) were cultured in the presence of IL-6, IL-1?, TNF-?, IGF-I, or FGF-2 before evaluation of proliferation and differentiation. Data were analyzed using PROC MIXED in SAS. Body weight increased from Fall1 to Spring in weanlings ( < 0.001) and increased in all horses from Spring to Fall2 ( ? 0.02). Area and height of the LM increased over time ( < 0.001) and with increasing age group of horse ( ? 0.03), although there was no interaction of time and age ( > 0.61). There was a significant increase in LM area in all animals from Spring to Fall2 ( < 0.001) but not from Fall1 to Spring. Interleukin-6 and TNF-? decreased satellite cell proliferation by 14.9 and 11.5%, respectively ( ? 0.01). Interleukin-6 increased fusion 6.2%, whereas TNF-? decreased fusion 8.7% compared with control cells ( ? 0.001). Interleukin-1? had no effect on proliferation ( = 0.32) but tended to decrease fusion ( = 0.06). Satellite cell proliferation was increased 28.8 and 73.0% by IGF-I and FGF-2, respectively ( < 0.0001). Differentiation was decreased 13.1% in the presence of FGF-2 but increased 3.5% in the presence of IGF-I ( ? 0.01). In summary, the LM area increases over the course of a year in young horses with the most growth occurring in summer. By stimulating or inhibiting proliferation and differentiation of satellite cells, IL-6, TNF-?, IL-1?, IGF-I, and FGF-2 may alter muscle growth in young horses, thereby impacting athletic potential. PMID:26641176

  18. TGF-?/HA complex promotes tympanic membrane keratinocyte migration and proliferation via ErbB1 receptor

    SciTech Connect

    Mei Teh, Bing; Redmond, Sharon L.; Shen, Yi; Atlas, Marcus D.; Marano, Robert J.; Dilley, Rodney J.

    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.

  19. Hypoxia-mediated induction of acidic/basic fibroblast growth factor and platelet-derived growth factor in mononuclear phagocytes stimulates growth of hypoxic endothelial cells.

    PubMed Central

    Kuwabara, K; Ogawa, S; Matsumoto, M; Koga, S; Clauss, M; Pinsky, D J; Lyn, P; Leavy, J; Witte, L; Joseph-Silverstein, J

    1995-01-01

    Wound repair and tumor vascularization depend upon blood vessel growth into hypoxic tissue. Although hypoxia slows endothelial cell (EC) proliferation and suppresses EC basic fibroblast growth factor (bFGF) expression, we report that macrophages (MPs) exposed to PO2 approximately 12-14 torr (1 torr = 133.3 Pa) synthesize and release in a time-dependent manner platelet-derived growth factor (PDGF) and acidic/basic FGFs (a/bFGFs), which stimulate the growth of hypoxic ECs. Chromatography of hypoxic MP-conditioned medium on immobilized heparin with an ascending NaCl gradient resolved three peaks of mitogenic activity: activity of the first peak was neutralized by antibody to PDGF; activity of the second peak was neutralized by antibody to aFGF; and activity of the third peak was neutralized by antibody to bFGF. Metabolically labeled lysates and supernatants from MPs exposed to hypoxia showed increased synthesis and release of immunoprecipitable PDGF and a/bFGF in the absence of changes in cell viability. Possible involvement of a heme-containing oxygen sensor in MP elaboration of growth factors was suggested by the induction of bFGF and PDGF by normoxic MPs exposed to nickel or cobalt, although metabolic inhibitors such as sodium azide were without effect. These results suggest a paracrine model in which hypoxia stimulates MP release of PDGF and a/bFGF, inducing EC proliferation and potentially promoting angiogenesis in hypoxic environments. Images Fig. 1 Fig. 3 Fig. 4 PMID:7538678

  20. Irritancy testing in cultured keratinocytes.

    PubMed

    Gajjar, L; Benford, D J

    A differentiating keratinocyte cell line derived from explant cultures of rat sublingual epithelium has been used as a potential in vitro model for topical (skin) irritation of a range of detergents. The end points used to assess toxicity were acid phosphatase (AP) activity after 4 h of dosing and neutral red (NR) uptake and kenacid blue (KB) staining after 3 d to assess cell viability and number. The acid phosphatase activity increased to a sharp peak with increasing doses, then fell equally sharply for the anionic detergent sodium dodecyl sulfate (SDS) and cationic detergents TMABs (trimethylammonium bromides). With the Tweens (the least toxic group) there was no acid phosphatase peak or it appeared at the highest dose level used (1.0 mg/ml). The dose-response curves for NR uptake paralleled those for KB staining. With all of the three end points, it was apparent that the order of toxicity for the different groups was TMABs greater than SDS greater than Tweens, with a difference of one order of magnitude between consecutive groups when using NR and KB. PMID:2476673

  1. 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

  2. Fibroblast Growth Factor 21 Analogs for Treating Metabolic Disorders

    PubMed Central

    Zhang, Jun; Li, Yang

    2015-01-01

    Fibroblast growth factor (FGF) 21 is a member of the endocrine FGF subfamily. FGF21 expression is induced under different disease conditions, such as type 2 diabetes, obesity, chronic kidney diseases, and cardiovascular diseases, and it has a broad spectrum of functions in regulating various metabolic parameters. Many different approaches have been pursued targeting FGF21 and its receptors to develop therapeutics for treating type 2 diabetes and other aspects of metabolic conditions. In this article, we summarize some of these key approaches and highlight the potential challenges in the development of these agents. PMID:26594197

  3. [Fibroblast growth factor 23--a phosphate regulating hormone].

    PubMed

    Beck-Nielsen, Signe Sparre; Pedersen, Susanne Møller; Kassem, Moustapha; Rasmussen, Lars Melholt

    2010-05-17

    Fibroblast growth factor 23 (FGF23) is a recently identified phosphatonin. Its main physiological functions are to maintain serum phosphate within its reference range and to counter regulate the effects of vitamin D. Diseases correlated to high serum values of FGF23 are hypophosphatemic rickets, fibrous dysplasia, and tumour-induced osteomalacia. In contrast, hyperphosphatemic tumoral calcinosis is associated with accelerated degradation of FGF23. Measuring FGF23 serves as a differential diagnostic tool in elucidating conditions of long-lasting hypophosphatemia. PMID:20483099

  4. Transforming growth factor ? transforms astrocytes to a growth-supportive phenotype after spinal cord injury.

    PubMed

    White, Robin E; Rao, Meghan; Gensel, John C; McTigue, Dana M; Kaspar, Brian K; Jakeman, Lyn B

    2011-10-19

    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 on which axons traverse. We have shown that intrathecal administration of transforming growth factor ? (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 whether endogenous EGFR activation is required after injury, SCI was also performed on Velvet (C57BL/6J-Egfr(Vel)/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 after injury. PMID:22016551

  5. 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

  6. Blockade of nonhormonal fibroblast growth factors by FP-1039 inhibits growth of multiple types of cancer.

    PubMed

    Harding, Thomas C; Long, Li; Palencia, Servando; Zhang, Hongbing; Sadra, Ali; Hestir, Kevin; Patil, Namrata; Levin, Anita; Hsu, Amy W; Charych, Deborah; Brennan, Thomas; Zanghi, James; Halenbeck, Robert; Marshall, Shannon A; Qin, Minmin; Doberstein, Stephen K; Hollenbaugh, Diane; Kavanaugh, W Michael; Williams, Lewis T; Baker, Kevin P

    2013-03-27

    The fibroblast growth factor (FGF) pathway promotes tumor growth and angiogenesis in many solid tumors. Although there has long been interest in FGF pathway inhibitors, development has been complicated: An effective FGF inhibitor must block the activity of multiple mitogenic FGF ligands but must spare the metabolic hormone FGFs (FGF-19, FGF-21, and FGF-23) to avoid unacceptable toxicity. To achieve these design requirements, we engineered a soluble FGF receptor 1 Fc fusion protein, FP-1039. FP-1039 binds tightly to all of the mitogenic FGF ligands, inhibits FGF-stimulated cell proliferation in vitro, blocks FGF- and vascular endothelial growth factor (VEGF)-induced angiogenesis in vivo, and inhibits in vivo growth of a broad range of tumor types. FP-1039 antitumor response is positively correlated with RNA levels of FGF2, FGF18, FGFR1c, FGFR3c, and ETV4; models with genetic aberrations in the FGF pathway, including FGFR1-amplified lung cancer and FGFR2-mutated endometrial cancer, are particularly sensitive to FP-1039-mediated tumor inhibition. FP-1039 does not appreciably bind the hormonal FGFs, because these ligands require a cell surface co-receptor, klotho or ?-klotho, for high-affinity binding and signaling. Serum calcium and phosphate levels, which are regulated by FGF-23, are not altered by administration of FP-1039. By selectively blocking nonhormonal FGFs, FP-1039 treatment confers antitumor efficacy without the toxicities associated with other FGF pathway inhibitors. PMID:23536011

  7. Human fetal and adult chondrocytes. Effect of insulinlike growth factors I and II, insulin, and growth hormone on clonal growth.

    PubMed Central

    Vetter, U; Zapf, J; Heit, W; Helbing, G; Heinze, E; Froesch, E R; Teller, W M

    1986-01-01

    Clonal proliferation of freshly isolated human fetal chondrocytes and adult chondrocytes in response to human insulinlike growth factors I and II (IGF I, IGF II), human biosynthetic insulin, and human growth hormone (GH) was assessed. IGF I (25 ng/ml) stimulated clonal growth of fetal chondrocytes (54 +/- 12 colonies/1,000 inserted cells, mean +/- 1 SD), but IGF II (25 ng/ml) was significantly more effective (106 +/- 12 colonies/1,000 inserted cells, P less than 0.05, unstimulated control: 14 +/- 4 colonies/1,000 inserted cells). In contrast, IGF I (25 ng/ml) was more effective in adult chondrocytes (42 +/- 6 colonies/1,000 inserted cells) than IGF II (25 ng/ml) (21 +/- 6 colonies/1,000 inserted cells; P less than 0.05, unstimulated control: 6 +/- 3 colonies/1,000 inserted cells). GH and human biosynthetic insulin did not affect clonal growth of fetal or adult chondrocytes. The clonal growth pattern of IGF-stimulated fetal and adult chondrocytes was not significantly changed when chondrocytes were first grown in monolayer culture, harvested, and then inserted in the clonal culture system. However, the adult chondrocytes showed a time-dependent decrease of stimulation of clonal growth by IGF I and II. This was not true for fetal chondrocytes. The results are compatible with the concept that IGF II is a more potent stimulant of clonal growth of chondrocytes during fetal life, whereas IGF I is more effective in stimulating clonal growth of chondrocytes during postnatal life. Images PMID:3519682

  8. Calcium influences sensitivity to growth inhibition induced by a cell surface sialoglycopeptide

    NASA Technical Reports Server (NTRS)

    Betz, N. A.; Fattaey, H. K.; Johnson, T. C.; Spooner, B. S. (Principal Investigator)

    1994-01-01

    While studies concerning mitogenic factors have been an important area of research for many years, much less is understood about the mechanisms of action of cell surface growth inhibitors. We have purified an 18 kDa cell surface sialoglycopeptide growth inhibitor (CeReS-18) which can reversibly inhibit the proliferation of diverse cell types. The studies discussed in this article show that three mouse keratinocyte cell lines exhibit sixty-fold greater sensitivity than other fibroblasts and epithelial-like cells to CeReS-18-induced growth inhibition. Growth inhibition induced by CeReS-18 treatment is a reversible process, and the three mouse keratinocyte cell lines exhibited either single or multiple cell cycle arrest points, although a predominantly G0/G1 cell cycle arrest point was exhibited in Swiss 3T3 fibroblasts. The sensitivity of the mouse keratinocyte cell lines to CeReS-18-induced growth inhibition was not affected by the degree of tumorigenic progression in the cell lines and was not due to differences in CeReS-18 binding affinity or number of cell surface receptors per cell. However, the sensitivity of both murine fibroblasts and keratinocytes could be altered by changing the extracellular calcium concentration, such that increased extracellular calcium concentrations resulted in decreased sensitivity to CeReS-18-induced proliferation inhibition. Thus the increased sensitivity of the murine keratinocyte cell lines to CeReS-18 could be ascribed to the low calcium concentration used in their propagation. Studies are currently under way investigating the role of calcium in CeReS-18-induced growth arrest. The CeReS-18 may serve as a very useful tool to study negative growth control and the signal transduction events associated with cell cycling.

  9. Delivering Heparin-Binding Insulin-Like Growth Factor 1 with Self-Assembling Peptide Hydrogels

    E-print Network

    Miller, Rachel E.

    Heparin-binding insulin-like growth factor 1 (HB-IGF-1) is a fusion protein of IGF-1 with the HB domain of heparin-binding epidermal growth factor-like growth factor. A single dose of HB-IGF-1 has been shown to bind ...

  10. Micron-Scale Spatially Patterned, Covalently Immobilized Vascular Endothelial Growth Factor on Hydrogels

    E-print Network

    Chen, Christopher S.

    such as vascular endothelial growth factor (VEGF). In vivo, endothelial cells respond to VEGF by formingMicron-Scale Spatially Patterned, Covalently Immobilized Vascular Endothelial Growth Factor-glycine-aspartic acid-serine (RGDS), an integrin ligand, and vascular endothelial growth factor (VEGF), a rate

  11. Huntingtin-associated Protein 1 Interacts with Hepatocyte Growth Factor-regulated Tyrosine Kinase Substrate and

    E-print Network

    Li, Lian

    epidermal growth factor receptors. Whereas overexpression of HAP1 does not affect either constitutive epidermal growth factor receptors from early endo- somes to late endosomes. These findings implicate of the cytokine and of the transforming growth factor- receptor via interaction with signal transducin

  12. The Response of Dorsal Root Ganglion Axons to Nerve Growth Factor Gradients Depends on Spinal Level

    E-print Network

    Goodhill, Geoffrey J.

    The Response of Dorsal Root Ganglion Axons to Nerve Growth Factor Gradients Depends on Spinal Level assay to generate precisely controllable nerve growth factor gradients, we show for the first time that the guidance and outgrowth response of rat dorsal root ganglion neurons to identical nerve growth factor

  13. ESCRT factors restrict mycobacterial growth Jennifer A. Philips*, Maura C. Porto*, Hui Wang*, Eric J. Rubin

    E-print Network

    Higgins, Darren

    ESCRT factors restrict mycobacterial growth Jennifer A. Philips*, Maura C. Porto*, Hui Wang*, Eric of these factors the cell no longer restricts growth of the non- pathogen Mycobacterium smegmatis. Hence, we screen to identify host factors that influence the uptake and growth of mycobacteria (6). We developed

  14. Individualbased simulation of the clustering behaviour of epidermal growth factor receptors.

    E-print Network

    Kent, University of

    Individual­based simulation of the clustering behaviour of epidermal growth factor receptors. Jacki on a project to simulate the behaviour of epidermal growth factor receptors. These are struc­ tures which can). A particular example of a system of this type is the epidermal growth factors (EGFs) and their receptors [25

  15. Smoothed Analysis of the Condition Numbers and Growth Factors of Matrices

    E-print Network

    Spielman, Daniel A.

    Smoothed Analysis of the Condition Numbers and Growth Factors of Matrices Arvind Sankar Department it is unlikely that A has large growth factor under Gaussian elimination without pivoting. By combining of arbitrary matrices are unlikely to have large condition numbers or large growth factors under Gaussian

  16. VEGF121 and VEGF165 Regulate Blood Vessel Diameter Through Vascular Endothelial Growth Factor Receptor

    E-print Network

    Hughes, Christopher C. W.

    VEGF121 and VEGF165 Regulate Blood Vessel Diameter Through Vascular Endothelial Growth Factor, Orange, California SUMMARY: Vascular endothelial growth factor (VEGF) is essential for the induction vessel diameter. Placental growth factor, which binds to VEGFR-1 but not VEGFR-2, does not promote

  17. Hrs Interacts with Sorting Nexin 1 and Regulates Degradation of Epidermal Growth Factor Receptor*

    E-print Network

    Li, Lian

    Hrs Interacts with Sorting Nexin 1 and Regulates Degradation of Epidermal Growth Factor Receptor 27599 Hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs) is a mammalian homologue homologue of yeast Vps5p that recognizes the lysosomal targeting code of epidermal growth factor receptor

  18. Nanosize effect on the hygroscopic growth factor of aerosol particles G. Biskos,1

    E-print Network

    Nanosize effect on the hygroscopic growth factor of aerosol particles G. Biskos,1 L. M. Russell,2 P February 2006; published 1 April 2006. [1] The hygroscopic growth factors of NaCl particles having dry. The growth factors steadily decreased within detection limit for dry sizes below 40 nm. The decrease

  19. 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 of...

  20. Immobilization of Growth Factors on Collagen Scaffolds Mediated by Polyanionic Collagen Mimetic Peptides and Its

    E-print Network

    Chen, Christopher S.

    Immobilization of Growth Factors on Collagen Scaffolds Mediated by Polyanionic Collagen Mimetic-terminus designed to attract growth factors by charge-charge interactions and bind to collagen by CMP attracting vascular endothelial growth factors (VEGFs), which led to enhanced morphological features of ECs

  1. Arsenite suppression of BMP signaling in human keratinocytes

    SciTech Connect

    Phillips, Marjorie A.; Qin, Qin; Hu, Qin; Zhao, Bin; Rice, Robert H.

    2013-06-15

    Arsenic, a human skin carcinogen, suppresses differentiation of cultured keratinocytes. Exploring the mechanism of this suppression revealed that BMP-6 greatly increased levels of mRNA for keratins 1 and 10, two of the earliest differentiation markers expressed, a process prevented by co-treatment with arsenite. BMP also stimulated, and arsenite suppressed, mRNA for FOXN1, an important transcription factor driving early keratinocyte differentiation. Keratin mRNAs increased slowly after BMP-6 addition, suggesting they are indirect transcriptional targets. Inhibition of Notch1 activation blocked BMP induction of keratins 1 and 10, while FOXN1 induction was largely unaffected. Supporting a requirement for Notch1 signaling in keratin induction, BMP increased levels of activated Notch1, which was blocked by arsenite. BMP also greatly decreased active ERK, while co-treatment with arsenite maintained active ERK. Inhibition of ERK signaling mimicked BMP by inducing keratin and FOXN1 mRNAs and by increasing active Notch1, effects blocked by arsenite. Of 6 dual-specificity phosphatases (DUSPs) targeting ERK, two were induced by BMP unless prevented by simultaneous exposure to arsenite and EGF. Knockdown of DUSP2 or DUSP14 using shRNAs greatly reduced FOXN1 and keratins 1 and 10 mRNA levels and their induction by BMP. Knockdown also decreased activated Notch1, keratin 1 and keratin 10 protein levels, both in the presence and absence of BMP. Thus, one of the earliest effects of BMP is induction of DUSPs, which increases FOXN1 transcription factor and activates Notch1, both required for keratin gene expression. Arsenite prevents this cascade by maintaining ERK signaling, at least in part by suppressing DUSP expression. - Highlights: • BMP induces FOXN1 transcription. • BMP induces DUSP2 and DUSP14, suppressing ERK activation. • Arsenite suppresses levels of phosphorylated Smad1/5 and FOXN1 and DUSP mRNA. • These actions rationalize arsenite suppression of keratinocyte differentiation.

  2. Loss of Tumor Necrosis Factor ? Potentiates Transforming Growth Factor ?-mediated Pathogenic Tissue Response during Wound Healing

    PubMed Central

    Saika, Shizuya; Ikeda, Kazuo; Yamanaka, Osamu; Flanders, Kathleen C.; Okada, Yuka; Miyamoto, Takeshi; Kitano, Ai; Ooshima, Akira; Nakajima, Yuji; Ohnishi, Yoshitaka; Kao, Winston W.-Y.

    2006-01-01

    Animal cornea is an avascular transparent tissue that is suitable for research on wound healing-related scarring and neovascularization. Here we show that loss of tumor necrosis factor ? (TNF?) potentiates the undesirable, pathogenic response of wound healing in an alkali-burned cornea in mice. Excessive invasion of macrophages and subsequent formation of a vascularized scar tissue were much more marked in TNF?-null knockout (KO) mice than in wild-type mice. Such an unfavorable outcome in KO mice was abolished by Smad7 gene introduction, indicating the involvement of transforming growth factor ? or activin/Smad signaling. Bone marrow transplantation from wild-type mice normalized healing of the KO mice, suggesting the involvement of bone marrow-derived inflammatory cells in this phenomenon. Co-culture experiments showed that loss of TNF? in macrophages, but not in fibroblasts, augmented the fibroblast activation as determined by detection of ?-smooth muscle actin, the hallmark of myofibroblast generation, mRNA expression of collagen I?2 and connective tissue growth factor, and detection of collagen protein. TNF? in macrophages may be required to suppress undesirable excessive inflammation and scarring, both of which are promoted by transforming growth factor ?, and for restoration of tissue architecture in a healing alkali-burned cornea in mice. PMID:16723700

  3. Combined vascular endothelial growth factor-A and fibroblast growth factor 4 gene transfer improves wound healing in diabetic mice

    PubMed Central

    2010-01-01

    Background Impaired wound healing in diabetes is related to decreased production of growth factors. Hence, gene therapy is considered as promising treatment modality. So far, efforts concentrated on single gene therapy with particular emphasis on vascular endothelial growth factor-A (VEGF-A). However, as multiple proteins are involved in this process it is rational to test new approaches. Therefore, the aim of this study was to investigate whether single AAV vector-mediated simultaneous transfer of VEGF-A and fibroblast growth factor 4 (FGF4) coding sequences will improve the wound healing over the effect of VEGF-A in diabetic (db/db) mice. Methods Leptin receptor-deficient db/db mice were randomized to receive intradermal injections of PBS or AAVs carrying ?-galactosidase gene (AAV-LacZ), VEGF-A (AAV-VEGF-A), FGF-4 (AAV-FGF4-IRES-GFP) or both therapeutic genes (AAV-FGF4-IRES-VEGF-A). Wound healing kinetics was analyzed until day 21 when all animals were sacrificed for biochemical and histological examination. Results Complete wound closure in animals treated with AAV-VEGF-A was achieved earlier (day 19) than in control mice or animals injected with AAV harboring FGF4 (both on day 21). However, the fastest healing was observed in mice injected with bicistronic AAV-FGF4-IRES-VEGF-A vector (day 17). This was paralleled by significantly increased granulation tissue formation, vascularity and dermal matrix deposition. Mechanistically, as shown in vitro, FGF4 stimulated matrix metalloproteinase-9 (MMP-9) and VEGF receptor-1 expression in mouse dermal fibroblasts and when delivered in combination with VEGF-A, enhanced their migration. Conclusion Combined gene transfer of VEGF-A and FGF4 can improve reparative processes in the wounded skin of diabetic mice better than single agent treatment. PMID:20804557

  4. Inhibitory action of transforming growth factor beta on endothelial cells.

    PubMed Central

    Müller, G; Behrens, J; Nussbaumer, U; Böhlen, P; Birchmeier, W

    1987-01-01

    In the present study, we show that transforming growth factor beta (TGF-beta) strongly inhibits fibroblast growth factor-induced proliferation and motility of bovine endothelial cells in tissue culture. TGF-beta also prevents the phorbol ester-induced invasion of capillary endothelial cells into collagen matrices--i.e., blocks angiogenesis in vitro. TGF-beta promotes the incorporation of fibronectin into the extracellular matrix of endothelial cells and stimulates the secretion of other proteins--mainly of 55- and 180-kDa components. We show furthermore that endothelial cells express TGF-beta receptors similar in size to those of other tissue culture cell lines: a 280-kDa complex is present in subconfluent cells, and 85- and 72-kDa protein bands are seen in confluent cells. The various effects of TGF-beta on endothelial cells suggest that these cells are an important target of TGF-beta during wound healing and angiogenesis. Images PMID:2441387

  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. Fibroblast growth factor receptors, developmental corruption and malignant disease.

    PubMed

    Kelleher, Fergal C; O'Sullivan, Hazel; Smyth, Elizabeth; McDermott, Ray; Viterbo, Antonella

    2013-10-01

    Fibroblast growth factors (FGF) are a family of ligands that bind to four different types of cell surface receptor entitled, FGFR1, FGFR2, FGFR3 and FGFR4. These receptors differ in their ligand binding affinity and tissue distribution. The prototypical receptor structure is that of an extracellular region comprising three immunoglobulin (Ig)-like domains, a hydrophobic transmembrane segment and a split intracellular tyrosine kinase domain. Alternative gene splicing affecting the extracellular third Ig loop also creates different receptor isoforms entitled FGFRIIIb and FGFRIIIc. Somatic fibroblast growth factor receptor (FGFR) mutations are implicated in different types of cancer and germline FGFR mutations occur in developmental syndromes particularly those in which craniosynostosis is a feature. The mutations found in both conditions are often identical. Many somatic FGFR mutations in cancer are gain-of-function mutations of established preclinical oncogenic potential. Gene amplification can also occur with 19-22% of squamous cell lung cancers for example having amplification of FGFR1. Ontologic comparators can be informative such as aberrant spermatogenesis being implicated in both spermatocytic seminomas and Apert syndrome. The former arises from somatic FGFR3 mutations and Apert syndrome arises from germline FGFR2 mutations. Finally, therapeutics directed at inhibiting the FGF/FGFR interaction are a promising subject for clinical trials. PMID:23880303

  7. MicroRNA-191 triggers keratinocytes senescence by SATB1 and CDK6 downregulation

    SciTech Connect

    Lena, A.M.; Mancini, M.; Rivetti di Val Cervo, P. [University of 'Tor Vergata', Department of Experimental Medicine and Biochemical Sciences, Via Montpellier 1, Rome 00133; Istituto Dermopatico dell'Immacolata-Istituto di Ricovero e Cura a Carattere Scientifico , Laboratory of Biochemistry c Saintigny, G.; Mahe, C. [CHANEL Parfums Beaute, 135 av. Charles de Gaulle, F 92521, Neuilly Melino, G. [University of 'Tor Vergata', Department of Experimental Medicine and Biochemical Sciences, Via Montpellier 1, Rome 00133; Istituto Dermopatico dell'Immacolata-Istituto di Ricovero e Cura a Carattere Scientifico , Laboratory of Biochemistry c Association Cell Death and Differentiation c and others

    2012-07-06

    Highlights: Black-Right-Pointing-Pointer miR-191 expression is upregulated in senescencent human epidermal keratinocytes. Black-Right-Pointing-Pointer miR-191 overexpression is sufficient per se to induce senescence in keratinocytes. Black-Right-Pointing-Pointer SATB1 and CDK6 are downregulated in senescence and are direct miR-191 targets. Black-Right-Pointing-Pointer SATB1 and CDK6 silencing by siRNA triggers senescence in HEKn cells. -- Abstract: Keratinocyte replicative senescence has an important role in time-dependent changes of the epidermis, a tissue with high turnover. Senescence encompasses growth arrest during which cells remain metabolically active but acquire a typical enlarged, vacuolar and flattened morphology. It is also accompanied by the expression of endogenous senescence-associated-{beta}-galactosidase and specific gene expression profiles. MicroRNAs levels have been shown to be modulated during keratinocytes senescence, playing key roles in inhibiting proliferation and in the acquisition of senescent markers. Here, we identify miR-191 as an anti-proliferative and replicative senescence-associated miRNA in primary human keratinocytes. Its overexpression is sufficient per se to induce senescence, as evaluated by induction of several senescence-associated markers. We show that SATB1 and CDK6 3 Prime UTRs are two miR-191 direct targets involved in this pathway. Cdk6 and Satb1 protein levels decrease during keratinocytes replicative senescence and their silencing by siRNA is able to induce a G1 block in cell cycle, accompanied by an increase in senescence-associated markers.

  8. Rapid population growth and environmental degradation: ultimate versus proximate factors.

    PubMed

    Shaw, R P

    1989-01-01

    This philosophical review of 2 arguments about responsibility for and solutions to environmental degradation concludes that both sides are correct: the ultimate and the proximal causes. Ultimate causes of pollution are defined as the technology responsible for a given type of pollution, such as burning fossil fuel; proximate causes are defined as situation-specific factors confounding the problem, such as population density or rate of growth. Commoner and others argue that developed countries with low or negative population growth rates are responsible for 80% of world pollution, primarily in polluting technologies such as automobiles, power generation, plastics, pesticides, toxic wastes, garbage, warfaring, and nuclear weapons wastes. Distortionary policies also contribute; examples are agricultural trade protection, land mismanagement, urban bias in expenditures, and institutional rigidity., Poor nations are responsible for very little pollution because poverty allows little waste or expenditures for polluting, synthetic technologies. The proximal causes of pollution include numbers and rate of growth of populations responsible for the pollution. Since change in the ultimate cause of pollution remains out of reach, altering the numbers of polluters can make a difference. Predictions are made for proportions of the world's total waste production, assuming current 1.6 tons/capita for developed countries and 0.17 tons/capita for developing countries. If developing countries grow at current rates and become more wealthy, they will be emitting half the world's waste by 2025. ON the other hand, unsustainable population growth goes along with inadequate investment in human capital: education, health, employment, infrastructure. The solution is to improve farming technologies in the 117 non-self-sufficient countries, fund development in the most unsustainable enclaves of growing countries, break institutionalized socio-political rigidity in these enclaves, and focus on educating and empowering women in these enclaves. Women are in charge of birth spacing and all aspects of management of energy, food, water and the local environment, more so than men, in most countries. PMID:12284190

  9. Transforming growth factor-?, insulin-like growth factor I/insulin-like growth factor I receptor and vascular endothelial growth factor-A: Prognostic and predictive markers in triple-negative and non-triple-negative breast cancer

    PubMed Central

    BAHHNASSY, ABEER; MOHANAD, MARWA; SHAARAWY, SABRY; ISMAIL, MANAL F.; EL-BASTAWISY, AHMED; ASHMAWY, ABEER M.; ZEKRI, ABDEL-RAHMAN

    2015-01-01

    In the current study, the prognostic and predictive values of serum transforming growth factor-?1 (TGF-?1), insulin-like growth factor I (IGF-I)/IGF-I receptor (IGF-IR) and vascular endothelial growth factor-A (VEGF-A) were evaluated in triple-negative and non-triple-negative breast cancer (TNBC and non-TNBC). The aim was to identify a group of serological biomarkers and to identify possible candidates for targeted therapy in patients with TNBC and non-TNBC. Protein levels of TGF-?1, IGF-I/IGF-IR and VEGF-A in the serum were measured in 43 TNBC, 53 non-TNBC and 20 normal control participants using quantitative ELISA assays. Results were correlated against standard prognostic factors, response to treatment and survival. TNBC was identified to be associated with poor prognosis and serum levels of VEGF-A and IGF/IGF-IR were significantly higher in the TNBC group compared with the non-TNBC group. IGF-IR and VEGF-A overexpression was observed to be correlated with TGF-?1 expression and all of the markers investigated were associated with metastasis and disease progression. In the multivariate analysis, VEGF-A, IGF-I and IGF-IR were observed to be independent predictors for overall survival, whereas TGF-?1 and lymph node status were identified as independent predictors for disease-free survival. The overall response rate was significantly lower in patients with TNBC and those with high levels of TGF-?1, IGF-I/IGF-IR and VEGF-A. In view of the present results, it was concluded that TGF-?1, IGF-I/IGF-IR and VEGF-A overexpression is associated with the presence of aggressive tumors, which exhibit an increased probability of metastasis, a poor response to treatment and reduced survival rate. This indicates that VEGF-A, IGF-IR and IGF-I have the potential to be used as surrogate biomarkers and are promising candidates for targeted therapy, particularly in patients with TNBC. PMID:25824321

  10. The Use of Growth Factors and Other Humoral Agents to Accelerate and Enhance Burn Wound Healing

    PubMed Central

    Ching, Yiu-Hei; Sutton, Thomas L.; Pierpont, Yvonne N.; Robson, Martin C.; Payne, Wyatt G.

    2011-01-01

    Objective: Certain cytokines, especially those known as growth factors, have been demonstrated to mediate or modulate burn wound healing. Experimental and clinical evidence suggests that there are therapeutic advantages to the wound healing process when these agents are utilized. Positive effects have been reported for 4 types of wounds seen in the burn patient: partial-thickness wounds, full-thickness wounds, interstices of meshed skin grafts, and skin graft donor sites. Methods: A comprehensive literature search was performed using the MEDLINE, Ovid, and Web of Science databases to identify pertinent articles regarding growth factors and other cytokines in burns and wound healing. Results: The current knowledge about cytokine growth factors and their potential therapeutic applications in burn wound healing are discussed and reviewed. Conclusions: Platelet-derived growth factor, fibroblast growth factors, epidermal growth factors, transforming growth factor alpha, vascular endothelial growth factor, insulin-like growth factor I, nerve growth factor, transforming growth factor beta, granulocyte-macrophage colony-stimulating factor, and amnion-derived cellular cytokine solution have all been suggested to enhance the rate and quality of healing in 1 or more of these wounds encountered in burn care. PMID:22084646

  11. 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

  12. Effects of hepatocyte growth factor on glutathione synthesis, growth, and apoptosis is cell density-dependent

    SciTech Connect

    Yang Heping; Magilnick, Nathaniel; Xia Meng; Lu, Shelly C.

    2008-01-15

    Hepatocyte growth factor (HGF) is a potent hepatocyte mitogen that exerts opposing effects depending on cell density. Glutathione (GSH) is the main non-protein thiol in mammalian cells that modulates growth and apoptosis. We previously showed that GSH level is inversely related to cell density of hepatocytes and is positively related to growth. Our current work examined whether HGF can modulate GSH synthesis in a cell density-dependent manner and how GSH in turn influence HGF's effects. We found HGF treatment of H4IIE cells increased cell GSH levels only under subconfluent density. The increase in cell GSH under low density was due to increased transcription of GSH synthetic enzymes. This correlated with increased protein levels and nuclear binding activities of c-Jun, c-Fos, p65, p50, Nrf1 and Nrf2 to the promoter region of these genes. HGF acts as a mitogen in H4IIE cells under low cell density and protects against tumor necrosis factor {alpha} (TNF{alpha})-induced apoptosis by limiting JNK activation. However, HGF is pro-apoptotic under high cell density and exacerbates TNF{alpha}-induced apoptosis by potentiating JNK activation. The increase in cell GSH under low cell density allows HGF to exert its full mitogenic effect but is not necessary for its anti-apoptotic effect.

  13. Targeting placental growth factor/neuropilin 1 pathway inhibits growth and spread of medulloblastoma

    PubMed Central

    Snuderl, Matija; Batista, Ana; Kirkpatrick, Nathaniel D.; de Almodovar, Carmen Ruiz; 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.

    2013-01-01

    SUMMARY Medulloblastoma is the most common pediatric malignant brain tumor. Although current therapies improve survival, these regimens are highly toxic and 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 metastases, 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 (VEGFR1)—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

  14. 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.

  15. Does single intramuscular application of autologous conditioned plasma influence systemic circulating growth factors?

    PubMed

    Schippinger, Gert; Fankhauser, Florian; Oettl, Karl; Spirk, Stefan; Hofmann, Peter

    2012-01-01

    Platelet-rich plasma (PRP) has been employed to treat sports injuries to possibly accelerate healing and regeneration. This method offers some potential, especially for athletes. Growth factors are generally prohibited by the World Anti Doping Agency with exception to PRP which may induce adverse effects. The aim of this study was to evaluate any systemic increase of growth factors such as Insulin Like Growth Factor-1, Endothelial Growth Factors, Platelet-Derived Growth Factors, Fibroblast Growth Factors, Vascular-Endothelial Growth Factor and Transforming Growth Factors after local intramuscular administration of PRP in young, healthy male subjects keeping in mind adverse treatment effects. Enriched plasma from centrifuged blood samples was injected into the gluteus muscle. Venous blood was collected and serum prepared before as well as 0.5, 3 and 24 hours after PRP administration. Growth factors were analyzed using ELISA test kits. No significant systemic increase of growth factor levels was found after PRP injection except TGF-?2. For that reason the PRP method may be applied for muscle injury treatment in elite athletes although further studies are necessary to clarify the response to the unspecific increased TGF-?2 blood levels, which could increase the risk for local fibrosis. Key pointsMuscle injuryAutologous conditioned plasmaSystemic circulating growth factorsDoping. PMID:24149367

  16. Does Single Intramuscular Application of Autologous Conditioned Plasma Influence Systemic Circulating Growth Factors?

    PubMed Central

    Schippinger, Gert; Fankhauser, Florian; Oettl, Karl; Spirk, Stefan; Hofmann, Peter

    2012-01-01

    Platelet-rich plasma (PRP) has been employed to treat sports injuries to possibly accelerate healing and regeneration. This method offers some potential, especially for athletes. Growth factors are generally prohibited by the World Anti Doping Agency with exception to PRP which may induce adverse effects. The aim of this study was to evaluate any systemic increase of growth factors such as Insulin Like Growth Factor-1, Endothelial Growth Factors, Platelet-Derived Growth Factors, Fibroblast Growth Factors, Vascular-Endothelial Growth Factor and Transforming Growth Factors after local intramuscular administration of PRP in young, healthy male subjects keeping in mind adverse treatment effects. Enriched plasma from centrifuged blood samples was injected into the gluteus muscle. Venous blood was collected and serum prepared before as well as 0.5, 3 and 24 hours after PRP administration. Growth factors were analyzed using ELISA test kits. No significant systemic increase of growth factor levels was found after PRP injection except TGF-?2. For that reason the PRP method may be applied for muscle injury treatment in elite athletes although further studies are necessary to clarify the response to the unspecific increased TGF-?2 blood levels, which could increase the risk for local fibrosis. Key pointsMuscle injuryAutologous conditioned plasmaSystemic circulating growth factorsDoping PMID:24149367

  17. Growth factor delivery: How surface interactions modulate release in vitro and in vivo

    PubMed Central

    King, William J.; Krebsbach, Paul H.

    2013-01-01

    Biomaterial scaffolds have been extensively used to deliver growth factors to induce new bone formation. The pharmacokinetics of growth factor delivery has been a critical regulator of their clinical success. This review will focus on the surface interactions that control the non-covalent incorporation of growth factors into scaffolds and the mechanisms that control growth factor release from clinically relevant biomaterials. We will focus on the delivery of recombinant human bone morphogenetic protein-2 from materials currently used in the clinical practice, but also suggest how general mechanisms that control growth factor incorporation and release delineated with this growth factor could extend to other systems. A better understanding of the changing mechanisms that control growth factor release during the different stages of preclinical development could instruct the development of future scaffolds for currently untreatable injuries and diseases. PMID:22433783

  18. Pharmacokinetics and distribution of heparin-binding growth factor I (endothelial cell growth factor) in the rat

    SciTech Connect

    Rosengart, T.K.; Kuperschmid, J.P.; Maciag, T.; Clark, R.E.

    1989-02-01

    Heparin-binding growth factor I (HBGF I), previously designated as endothelial cell growth factor, is a potent mitogen for endothelial cells in vitro, which may prove useful for promoting endothelial regeneration in vivo. Analysis of the pharmacokinetics and organ distribution of HBGF I is necessary before use of HBGF I as a pharmacological agent. Consequently, pharmacological studies were carried out with (125I)HBGF I in the rat. Intravenous injections of HBGF I were given with or without heparin (2.5 units/ng HBGF I). Blood concentrations of HBGF I decreased by one half 17 seconds after HBGF I bolus. This time was prolonged to 60 seconds when HBGF I was injected with heparin. The elimination half-life of HBGF I was 14 minutes in the presence of heparin. The highest concentrations of HBGF I following intravenous bolus were found in kidney, liver, and spleen, and the lowest in fat and brain. Heparin increased HBGF I concentrations in blood and all organs measured except kidney, which was significantly decreased (p less than 0.01). Intact HBGF I was recoverable from blood 5 minutes following intravenous administration. HBGF I underwent near-complete proteolytic digestion after more prolonged ex vivo incubation with rat plasma, but HBGF I was protected from proteolysis when incubations were conducted in the presence of heparin. Thus, it is feasible that HBGF I can be administered as a pharmacological agent in the presence of heparin. Further studies assessing acceleration of in vivo endothelial growth using HBGF I with heparin appear warranted.

  19. A synthetic sandalwood odorant induces wound-healing processes in human keratinocytes via the olfactory receptor OR2AT4.

    PubMed

    Busse, Daniela; Kudella, Philipp; Grüning, Nana-Maria; Gisselmann, Günter; Ständer, Sonja; Luger, Thomas; Jacobsen, Frank; Steinsträßer, Lars; Paus, Ralf; Gkogkolou, Paraskevi; Böhm, Markus; Hatt, Hanns; Benecke, Heike

    2014-11-01

    As the outermost barrier of the body, the skin is exposed to multiple environmental factors, including temperature, humidity, mechanical stress, and chemical stimuli such as odorants that are often used in cosmetic articles. Keratinocytes, the major cell type of the epidermal layer, express a variety of different sensory receptors that enable them to react to various environmental stimuli and process information in the skin. Here we report the identification of a novel type of chemoreceptors in human keratinocytes, the olfactory receptors (ORs). We cloned and functionally expressed the cutaneous OR, OR2AT4, and identified Sandalore, a synthetic sandalwood odorant, as an agonist of this receptor. Sandalore induces strong Ca(2+) signals in cultured human keratinocytes, which are mediated by OR2AT4, as demonstrated by receptor knockdown experiments using RNA interference. The activation of OR2AT4 induces a cAMP-dependent pathway and phosphorylation of extracellular signal-regulated kinases (Erk1/2) and p38 mitogen-activated protein kinases (p38 MAPK). Moreover, the long-term stimulation of keratinocytes with Sandalore positively affected cell proliferation and migration, and regeneration of keratinocyte monolayers in an in vitro wound scratch assay. These findings combined with our studies on human skin organ cultures strongly indicate that the OR 2AT4 is involved in human keratinocyte re-epithelialization during wound-healing processes. PMID:24999593

  20. Akt enhances nerve growth factor-induced axon growth via activating the Nrf2/ARE pathway.

    PubMed

    Xia, Bin; Liu, Heyu; Xie, Juanke; Wu, Rui; Li, Yali

    2015-11-01

    Spinal cord injury (SCI) leads to the loss of structure and function of axons. However, injured axons cannot grow or regenerate spontaneously following injury. Generally, only when treated with neurotrophins, such as nerve growth factor (NGF), will the neurons sprout new axons. Akt is one of the central kinases of neurocytes. PC12 cells are a frequently used cell model for neural differentiation and development studies. The nuclear factor erythroid 2?related factor 2 (Nrf2)/antioxidant response element (ARE) signaling pathway is a main mechanism in prevention from oxidative stress, which may damage the nervous system. The present study employed this cell model to investigate whether Akt could induce axon growth in PC12 cells on the basis of NGF treatments. The results showed that Akt overexpression significantly increased cell proliferation and decreased cell apoptosis. Additionally, Akt overexpression activated Nrf2/ARE pathways. In conclusion, the experiments indicated that Akt overexpression contributed to axon regeneration induced by NGF in PC12 cells through activating the Nrf2/ARE pathway. PMID:26324295

  1. Growth factor delivery methods in the management of sports injuries: the state of play.

    PubMed

    Creaney, L; Hamilton, B

    2008-05-01

    In recent years there have been rapid developments in the use of growth factors for accelerated healing of injury. Growth factors have been used in maxillo-facial and plastic surgery with success and the technology is now being developed for orthopaedics and sports medicine applications. Growth factors mediate the biological processes necessary for repair of soft tissues such as muscle, tendon and ligament following acute traumatic or overuse injury, and animal studies have demonstrated clear benefits in terms of accelerated healing. There are various ways of delivering higher doses of growth factors to injured tissue, but each has in common a reliance on release of growth factors from blood platelets. Platelets contain growth factors in their alpha-granules (insulin-like growth factor-1, basic fibroblast growth factor, platelet-derived growth factor, epidermal growth factor, vascular endothelial growth factor, transforming growth factor-beta(1)) and these are released upon injection at the site of an injury. Three commonly utilised techniques are known as platelet-rich plasma, autologous blood injections and autologous conditioned serum. Each of these techniques has been studied clinically in humans to a very limited degree so far, but results are promising in terms of earlier return to play following muscle and particularly tendon injury. The use of growth factors in sports medicine is restricted under the terms of the World Anti-Doping Agency (WADA) anti-doping code, particularly because of concerns regarding the insulin-like growth factor-1 content of such preparations, and the potential for abuse as performance-enhancing agents. The basic science and clinical trials related to the technology are reviewed, and the use of such agents in relation to the WADA code is discussed. PMID:17984193

  2. Integral role of platelet-derived growth factor in mediating transforming growth factor-?1-dependent mesenchymal stem cell stiffening.

    PubMed

    Ghosh, Deepraj; Lili, Loukia; McGrail, Daniel J; Matyunina, Lilya V; McDonald, John F; Dawson, Michelle R

    2014-02-01

    Mesenchymal stem cells (MSCs) play an important role in matrix remodeling, fibroblast activation, angiogenesis, and immunomodulation and are an integral part of fibrovascular networks that form in developing tissues and tumors. The engraftment and function of MSCs in tissue niches is regulated by a multitude of soluble proteins. Transforming growth factor-?1 (TGF-?1) and platelet-derived growth factor-BB (PDGF) have previously been recognized for their role in MSC biology; thus, we sought to investigate their function in mediating MSC mechanics and matrix interactions. Cytoskeletal organization, characterized by cell elongation, stress fiber formation, and condensation of actin and microtubules, was dramatically affected by TGF-?1, individually and in combination with PDGF. The intracellular mechanical response to these stimuli was measured with particle tracking microrheology. MSCs stiffened in response to TGF-?1 (their elastic moduli was ninefold higher than control cells), a result that was enhanced by the addition of PDGF (100-fold change). Blocking TGF-?1 or PDGF signaling with inhibitors SB-505124 or JNJ-10198409, respectively, reversed soluble-factor-induced stiffening, indicating that crosstalk between these two pathways is essential for stiffening response. A genome-wide microarray analysis revealed TGF-?1-dependent regulation of cytoskeletal actin-binding protein genes. Actin crosslinking and bundling protein genes, which regulate cytosolic rheology through changes in semiflexible actin polymer meshwork, were upregulated with TGF-?1 treatment. TGF-?1 alone and in combination with PDGF also amplified surface integrin expression and adhesivity of MSCs with extracellular matrix proteins. These findings will provide a more mechanistic insight for modeling tissue-level rigidity in fibrotic tissues and tumors. PMID:24093435

  3. Cardiovascular gene therapy with vascular endothelial growth factors.

    PubMed

    Ylä-Herttuala, Seppo

    2013-08-10

    Therapeutic angiogenesis with vascular endothelial growth factors (VEGFs) is a promising approach for the treatment of ischemic myocardium and peripheral skeletal muscles. Preclinical studies in large animals have clearly demonstrated safety and efficacy of VEGF gene therapy in clinically relevant disease models. However, first clinical trials with intravascular delivery of VEGF vector constructs have only resulted in limited benefits to the patients. Second generation VEGF-based gene therapy trials are based on direct intramyocardial and intraskeletal muscle injections in order to achieve better transfection efficiency and more targeted effects. Phase I/II studies are currently ongoing to test safety, feasibility and efficacy of these improved approaches in patients with severe cardiovascular diseases. PMID:23608170

  4. Vascular Endothelial Growth Factor-C Accelerates Diabetic Wound Healing

    PubMed Central

    Saaristo, Anne; Tammela, Tuomas; F?rkkil?, Anniina; Kärkkäinen, Marika; Suominen, Erkki; Yla-Herttuala, Seppo; Alitalo, Kari

    2006-01-01

    Diabetes impairs numerous aspects of tissue repair. Failure of wound angiogenesis is known to delay diabetic wound healing, whereas the importance of lymphangiogenesis for wound healing is unclear. We have examined whether overexpression of vascular endothelial growth factor (VEGF)-C via an adenoviral vector could improve the healing of full-thickness punch biopsy wounds in genetically diabetic (db/db) mice. We found that VEGF-C enhanced angiogenesis and lymphangiogenesis in the wound and significantly accelerated wound healing in comparison to the control wounds. VEGF-C also recruited inflammatory cells, some of which expressed VEGFR-3. On the other hand, when the function of endogenous VEGF-C/VEGF-D was blocked with a specific inhibitor, wound closure was delayed even further. These results suggest a function for VEGF-C in wound healing and demonstrate the therapeutic potential of VEGF-C in the treatment of diabetic wounds. PMID:16936280

  5. Transforming Growth Factor-? and the Hallmarks of Cancer

    PubMed Central

    Tian, Maozhen; Neil, Jason R.; Schiemann, William P.

    2010-01-01

    Tumorigenesis is in many respects a process of dysregulated cellular evolution that drives malignant cells to acquire six phenotypic hallmarks of cancer, including their ability to proliferate and replicate autonomously, to resist cytostatic and apoptotic signals, and to induce tissue invasion, metastasis, and angiogenesis. Transforming growth factor-? (TGF-?) is a potent pleiotropic cytokine that functions as a formidable barrier to the development of cancer hallmarks in normal cells and tissues. Paradoxically, tumorigenesis counteracts the tumor suppressing activities of TGF-?, thus enabling TGF-? to stimulate cancer invasion and metastasis. Fundamental gaps exist in our knowledge of how malignant cells overcome the cytostatic actions of TGF-?, and of how TGF-? stimulates the acquisition of cancer hallmarks by developing and progressing human cancers. Here we review the molecular and cellular mechanisms that underlie the ability of TGF-? to mediate tumor suppression in normal cells, and conversely, to facilitate cancer progression and disease dissemination in malignant cells. PMID:20940046

  6. Targeting Mutant Fibroblast Growth Factor Receptors in Cancer

    PubMed Central

    Greulich, Heidi; Pollock, Pamela M.

    2013-01-01

    Fibroblast growth factor receptors (FGFRs) play diverse roles in control of cell proliferation, cell differentiation, angiogenesis, and development. Activating mutations of FGFRs in the germline have long been known to cause a variety of skeletal developmental disorders, but it is only recently that a similar spectrum of somatic FGFR mutations has been associated with human cancers. Many of these somatic mutations are gain-of-function and oncogenic and create dependencies in tumor cell lines harboring such mutations. A combination of knock-down studies and pharmaceutical inhibition in preclinical models has further substantiated genomically-altered FGFR as a therapeutic target in cancer, and the oncology community is responding with clinical trials evaluating multi-kinase inhibitors with anti-FGFR activity and a new generation of specific pan-FGFR inhibitors. PMID:21367659

  7. Basic Fibroblast Growth Factor Induces Angiogenesis in vitro

    NASA Astrophysics Data System (ADS)

    Montesano, R.; Vassalli, J.-D.; Baird, A.; Guillemin, R.; Orci, L.

    1986-10-01

    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 pituitary FGF can induce capillary endothelial cells to invade a three-dimensional collagen matrix and to organize themselves to form characteristic tubules that resemble blood capillaries. We also show that basic FGF concomitantly stimulates endothelial cells to produce a urokinase-type plasminogen activator, a protease that has been implicated in the neovascular response. The results demonstrate that basic FGF can stimulate processes that are characteristic of angiogenesis in vivo, including endothelial cell migration, invasion, and production of plasminogen activator.

  8. Epidermal growth factor receptor and variant III targeted immunotherapy

    PubMed Central

    Congdon, Kendra L.; Gedeon, Patrick C.; Suryadevara, Carter M.; Caruso, Hillary G.; Cooper, Laurence J.N.; Heimberger, Amy B.; Sampson, John H.

    2014-01-01

    Immunotherapeutic approaches to cancer have shown remarkable promise. A critical barrier to successfully executing such immune-mediated interventions is the selection of safe yet immunogenic targets. As patient deaths have occurred when tumor-associated antigens shared by normal tissue have been targeted by strong cellular immunotherapeutic platforms, route of delivery, target selection and the immune-mediated approach undertaken must work together to maximize efficacy with safety. Selected tumor-specific targets can spare potential toxicity to normal tissue; however, they are far less common than tumor-associated antigens and may not be present on all patients. In the context of immunotherapy for high-grade glioma, 2 of the most prominently studied antigens are the tumor-associated epidermal growth factor receptor and its tumor-specific genetic deletion variant III. In this review, we will summarize the immune-mediated strategies employed against these targets as well as the caveats particular to these approaches. PMID:25342601

  9. Proteasome Inhibition by Fellutamide B Induces Nerve Growth Factor Synthesis

    PubMed Central

    Hines, John; Groll, Michael; Fahnestock, Margaret; Crews, Craig M.

    2008-01-01

    SUMMARY Neurotrophic small molecules have the potential to aid in the treatment of neuronal injury and neurodegenerative diseases. The natural product fellutamide B, originally isolated from Penicillium fellutanum, potently induces nerve growth factor (NGF) release from fibroblasts and glial-derived cells, although the mechanism for this neurotrophic activity has not been elucidated. Here, we report that fellutamide B potently inhibits proteasome catalytic activity. High resolution structural information obtained from co-crystallization of the 20S proteasome reveals novel aspects regarding ?-subunit binding and adduct formation by fellutamide B to inhibit their hydrolytic activity. We demonstrate that fellutamide B and other proteasome inhibitors increased NGF gene transcription via a cis-acting element (or elements) in the promoter. These results demonstrate an unrecognized connection between proteasome inhibition and NGF production, suggesting a possible new strategy in the development of neurotrophic agents. PMID:18482702

  10. Proteasome inhibition by fellutamide B induces nerve growth factor synthesis.

    PubMed

    Hines, John; Groll, Michael; Fahnestock, Margaret; Crews, Craig M

    2008-05-01

    Neurotrophic small molecules have the potential to aid in the treatment of neuronal injury and neurodegenerative diseases. The natural product fellutamide B, originally isolated from Penicillium fellutanum, potently induces nerve growth factor (NGF) release from fibroblasts and glial-derived cells, although the mechanism for this neurotrophic activity has not been elucidated. Here, we report that fellutamide B potently inhibits proteasome catalytic activity. High-resolution structural information obtained from cocrystallization of the 20S proteasome reveals novel aspects regarding beta-subunit binding and adduct formation by fellutamide B to inhibit their hydrolytic activity. We demonstrate that fellutamide B and other proteasome inhibitors increased NGF gene transcription via a cis-acting element (or elements) in the promoter. These results demonstrate an unrecognized connection between proteasome inhibition and NGF production, suggesting a possible new strategy in the development of neurotrophic agents. PMID:18482702

  11. Targeting Fibroblast Growth Factor Pathways in Prostate Cancer

    PubMed Central

    Corn, Paul; Wang, Fen; McKeehan, Wallace L.; Navone, Nora

    2013-01-01

    Advanced prostate cancer carries a poor prognosis and novel therapies are needed. Research has focused on identifying mechanisms that promote angiogenesis and cellular proliferation during prostate cancer progression from the primary tumor to bone—the principal site of prostate cancer metastases. One candidate pathway is the fibroblast growth factor (FGF) axis. Aberrant expression of FGF ligands and FGF receptors leads to constitutive activation of multiple downstream pathways involved in prostate cancer progression, including mitogen-activated protein kinase, phosphoinositide 3-kinase, and phospholipase C?. The involvement of FGF pathways in multiple mechanisms relevant to prostate tumorigenesis s provides a rationale for the therapeutic blockade of this pathway, and two small-molecule tyrosine kinase inhibitors—dovitinib and nintedanib—are currently in phase 2 clinical development for advanced prostate cancer. Preliminary results from these trials suggest that FGF pathway inhibition represents a promising new strategy to treat castrate-resistant disease. PMID:24052019

  12. Structural basis for agonism and antagonism of hepatocyte growth factor

    SciTech Connect

    Tolbert, W. David; Daugherty-Holtrop, Jennifer; Gherardi, Ermanno; Vande Woude, George; Xu, H. Eric

    2010-11-01

    Hepatocyte growth factor (HGF) is an activating ligand of the Met receptor tyrosine kinase, whose activity is essential for normal tissue development and organ regeneration but abnormal activation of Met has been implicated in growth, invasion, and metastasis of many types of solid tumors. HGF has two natural splice variants, NK1 and NK2, which contain the N-terminal domain (N) and the first kringle (K1) or the first two kringle domains of HGF. NK1, which is a Met agonist, forms a head-to-tail dimer complex in crystal structures and mutations in the NK1 dimer interface convert NK1 to a Met antagonist. In contrast, NK2 is a Met antagonist, capable of inhibiting HGF's activity in cell proliferation without clear mechanism. Here we report the crystal structure of NK2, which forms a 'closed' monomeric conformation through interdomain interactions between the N- domain and the second kringle domain (K2). Mutations that were designed to open up the NK2 closed conformation by disrupting the N/K2 interface convert NK2 from a Met antagonist to an agonist. Remarkably, this mutated NK2 agonist can be converted back to an antagonist by a mutation that disrupts the NK1/NK1 dimer interface. These results reveal the molecular determinants that regulate the agonist/antagonist properties of HGF NK2 and provide critical insights into the dimerization mechanism that regulates the Met receptor activation by HGF.

  13. Mechanisms of fibroblast growth factor signaling in the ovarian follicle.

    PubMed

    Price, Christopher A

    2016-02-01

    Fibroblast growth factors (FGFs) have been shown to alter growth and differentiation of reproductive tissues in a variety of species. Within the female reproductive tract, the effects of FGFs have been focused on the ovary, and the most studied one is FGF2, which stimulates granulosa cell proliferation and decreases differentiation (decreased steroidogenesis). Other FGFs have also been implicated in ovarian function, and this review summarizes the effects of members of two subfamilies on ovarian function; the FGF7 subfamily that also contains FGF10, and the FGF8 subfamily that also contains FGF18. There are data to suggest that FGF8 and FGF18 have distinct actions on granulosa cells, despite their apparent similar receptor binding properties. Studies of non-reproductive developmental biology also indicate that FGF8 is distinct from FGF18, and that FGF7 is also distinct from FGF10 despite similar receptor binding properties. In this review, the potential mechanisms of differential action of FGF7/FGF10 and FGF8/FGF18 during organogenesis will be reviewed and placed in the context of follicle development. A model is proposed in which FGF8 and FGF18 differentially activate receptors depending on the properties of the extracellular matrix in the follicle. PMID:26542145

  14. Neovasculature induced by vascular endothelial growth factor is fenestrated.

    PubMed

    Roberts, W G; Palade, G E

    1997-02-15

    We have reported previously that topical administration of vascular endothelial growth factor165 (VEGF) to a microvascular bed supplied with a continuous endothelium can rapidly induce the formation of endothelial fenestrations (W. G. Roberts and G. E. Palade, J. Cell Sci., 108: 2369-2379, 1995). From these results, we hypothesized that tumor vasculature, in general, may also be fenestrated because it has been reported that tumor secretion of VEGF causes the surrounding host vasculature to invade and feed the growing tumor. Using electron microscopy to characterize the endothelial cell morphology in tumor vessels from either the periphery or the core of the tumor and immunoblotting to detect secreted VEGF, we analyzed the vasculature of human and murine neoplastic tumors grown s.c. in male nude mice. To clarify the role of VEGF165 two models were used: (a) Chinese hamster ovary (CHO) cells stably transfected with hu VEGF165 and injected into mice (VEGF:CHO tumors); and (b) slow-release pellets containing purified VEGF or basic fibroblast growth factor implanted on the rat cremaster muscle. All tumors had vessels with fenestrated endothelium, open interendothelial junctions, and clustered fused caveolae. From all of the peripheral tumor vessels observed, fenestrated endothelium was observed in 41% from EMT, 35% from M1S, 37% from U87, and 56% from VEGF:CHO tumors, whereas surrounding skin and muscle, from which tumor vessels were derived, had fenestrated endothelium in 2 and 0% of all vessels, respectively. Additionally, further analysis revealed a substantial decrease in the anionic glycocalyx on the luminal face of the fenestral diaphragms in endothelium from tumors (especially VEGF:CHO) when compared to intestine or pancreas. Because the host tissue microvascular endothelium which supplies the tumor is not fenestrated, tumors can transform nonproliferating, nonfenestrated vessels into proliferating vessels, many of which have fenestrated endothelium. These data provide evidence that chronic VEGF exposure can induce fenestrations in nonfenestrated endothelium similar to the fenestrated endothelium found in tumor vessels. PMID:9044858

  15. REJUVENATION OF PERIOSTEAL CHONDROGENESIS USING LOCAL GROWTH FACTOR INJECTION

    PubMed Central

    Reinholz, G.G.; Fitzsimmons, J.S.; Casper, M.; Ruesink, T.J.; Chung, H.W.; Schagemann, J.C.; O’Driscoll, S.W.

    2015-01-01

    Objective To examine the potential for rejuvenation of aged periosteum by local injection of transforming growth factor-beta1 (TGF-?1) and insulin-like growth factor-1 (IGF-1) alone or in combination to induce cambium cell proliferation and enhance in vitro periosteal cartilage formation. Methods A total of 367 New Zealand white rabbits (6, 12, and 24+ month-old) received subperiosteal injections of TGF-?1 and/or IGF-1 percutaneously. After 1, 3, 5, or 7 days, the rabbits were sacrificed and cambium cellularity or in vitro cartilage forming capacity was determined. Results A significant increase in cambium cellularity and thickness, and in vitro cartilage formation was observed after injection of TGF-?1 alone or in combination with IGF-1. In 12 month-old rabbits, mean cambium cellularity increased 5-fold from 49 to 237 cells/mm and in vitro cartilage production increased 12-fold from 0.8 to 9.7 mg seven days after TGF-?1 (200 ng) injection compared to vehicle controls (p<0.0001). A correlation was observed between cambium cellularity and in vitro cartilage production (R2=0.98). An added benefit of IGF-1 plus TGF-?1 on in vitro cartilage production compared to TGF-?1 alone was observed in the 2 year old rabbits. IGF-1 alone generally had no effect on either cambium cellularity or in vitro cartilage production in any of the age groups. Conclusions These results clearly demonstrate that it is possible to increase cambium cellularity and in vitro cartilage production in aged rabbit periosteum, to levels comparable to younger rabbits, using local injection of TGF-?1 alone or in combination with IGF-1, thereby rejuvenating aged periosteum. PMID:19064326

  16. Profilin induces lamellipodia by growth factor-independent mechanism.

    PubMed

    Syriani, Enrique; Gomez-Cabrero, Azucena; Bosch, Marta; Moya, Alicia; Abad, Elena; Gual, Arcadi; Gasull, Xavier; Morales, Miguel

    2008-05-01

    Profilin has been implicated in cell motility and in a variety of cellular processes, such as membrane extension, endocytosis, and formation of focal complexes. In vivo, profilin replenish the pool of ATP-actin monomers by increasing the rate of nucleotide exchange of ADP-actin for ATP-actin, promoting the incorporation of new actin monomers at the barbed end of actin filaments. For this report, we generated a membrane-permeable version of profilin I (PTD4-PfnI) for the alteration of intracellular profilin levels taking advantage of the protein transduction technique. We show that profilin I induces lamellipodia formation independently of growth factor presence in primary bovine trabecular meshwork (BTM) cells. The effects are time- and concentration-dependent and specific to the profilin I isoform. Profilin II, the neuronal isoform, failed to extend lamellipodia in the same degree as profilin I. H133S, a mutation in the polyproline binding domain, showed a reduced ability to induce lamellipodia. H199E, mutation in the actin binding domain failed to induce membrane spreading and inhibit fetal bovine serum (FBS) -induced lamellipodia extension. Incubation with a synthetic polyproline domain peptide (GP5)3, fused to a transduction domain, abolished lamellipodia induction by profilin or FBS. Time-lapse microscopy confirmed the effects of profilin on lamellipodia extension with a higher spreading velocity than FBS. PTD4-Pfn I was found in the inner lamellipodia domain, at the membrane leading edge where it colocalizes with endogenous profilin. While FBS-induced lamellipodia formation activates Rac1, PTD4-Pfn I stimulation did not induce Rac1 activation. We propose a role of profilin I favoring lamellipodia formation by a mechanism downstream of growth factor. PMID:18184720

  17. GH modulates hepatic epidermal growth factor signaling in the mouse

    PubMed Central

    González, Lorena; Díaz, Ma Eugenia; Miquet, Johanna G; Sotelo, Ana I; Fernández, Diego; Dominici, Fernando P; Bartke, Andrzej; Turyn, Daniel

    2014-01-01

    Epidermal growth factor (EGF) is a key regulator of cell survival and proliferation involved in the pathogenesis and progression of different types of cancer. The EGF receptor (EGFR) is activated by binding of the specific ligand but also by transactivation triggered by different growth factors including GH. Chronically, elevated GH levels have been associated with the progression of hepatocellular carcinoma. Considering EGF and GH involvement in cell proliferation and their signaling crosstalk, the objective of the present study was to analyze GH modulatory effects on EGF signaling in liver. For this purpose, GH receptor-knockout (GHR-KO) and GH-overexpressing transgenic mice were used. EGFR content was significantly decreased in GHR-KO mice. Consequently, EGF–induced phosphorylation of EGFR, AKT, ERK1/2, STAT3, and STAT5 was significantly decreased in these mice. In contrast, EGFR content as well as its basal tyrosine phosphorylation was increased in transgenic mice overexpressing GH. However, EGF stimulation caused similar levels of EGFR, AKT, and ERK1/2 phosphorylation in normal and transgenic mice, while EGF induction of STAT3 and STAT5 phosphorylation was inhibited in the transgenic mice. Desensitization of the STATs was related to decreased association of these proteins to the EGFR and increased association between STAT5 and the tyrosine phosphatase SH2-containing phosphatase-2. While GHR knockout is associated with diminished expression of the EGFR and a concomitant decrease in EGF signaling, GH overexpression results in EGFR overexpression with different effects depending on the signaling pathway analyzed: AKT and ERK1/2 pathways are induced by EGF, while STAT3 and STAT5 activation is heterologously desensitized. PMID:20032199

  18. Endothelin inhibits cholangiocarcinoma growth by a decrease in the vascular endothelial growth factor expression

    PubMed Central

    Fava, Giammarco; DeMorrow, Sharon; Gaudio, Eugenio; Franchitto, Antonio; Onori, Paolo; Carpino, Guido; Glaser, Shannon; Francis, Heather; Coufal, Monique; Marucci, Luca; Alvaro, Domenico; Marzioni, Marco; Horst, Trenton; Mancinelli, Romina; Benedetti, Antonio; Alpini, Gianfranco

    2009-01-01

    Background: Endothelins (ET-1, ET-2, ET-3) are peptides with vasoactive properties interacting with ETA and ETB receptors. ET-1 inhibits secretin-stimulated ductal secretion (hallmark of cholangiocyte growth) of cholestatic rats by interaction with ET receptors. Aim: The aims of the studies were to evaluate (i) the effect of ET-1 on cholangiocarcinoma growth in Mz-ChA-1 cells and nude mice and (ii) whether ET-1 regulation of cholangiocarcinoma growth is associated with changes in the expression of vascular endothelial growth factor-A (VEGF-A), VEGF-C, VEGF receptor-2 (VEGFR-2) and VEGFR-3. Methods: We determined the expression of ETA and ETB receptors on normal and malignant (Mz-ChA-1) cholangiocytes and human cholangiocarcinoma tissue and the effect of ET-1 on the proliferation and expression of VEGF-A, VEGF-C (regulators of tumour angiogenesis) and its receptors, VEGFR-2 and VEGFR-3, in Mz-ChA-1 cells. In vivo, Mz-ChA-1 cells were injected into the flanks of athymic mice and injections of ET-1 or saline into the tumours were performed daily. The effect of ET-1 on tumour size, cell proliferation, apoptosis, collagen quantity and the expression of VEGF-A and VEGF-C and VEGFR-2 and VEGFR-3 were measured after 73 days. Results: Higher expression of ETA and ETB was observed in malignant compared with normal cholangiocytes. ET-1 inhibited proliferation and VEGF-A, VEGF-C, VEGFR-2 and VEGFR-3 expression of Mz-ChA-1 cells. Chronic ET-1 treatment decreased tumour volume, tumour cell proliferation and VEGF-A and VEGF-C expression but increased apoptosis and collagen tissue deposition compared with controls. Conclusions: Modulation of VEGF-A and VEGF-C (by ET-1) may be important for managing cholangiocarcinoma growth. PMID:19291182

  19. Multiple Mechanisms are Responsible for Transactivation of the Epidermal Growth Factor Receptor in Mammary Epithelial Cells

    SciTech Connect

    Rodland, Karin D.; Bollinger, Nikki; Ippolito, Danielle L.; Opresko, Lee; Coffey, Robert J.; Zangar, Richard C.; Wiley, H. S.

    2008-11-14

    REVIEW ENTIRE DOCUMENT AT: https://pnlweb.pnl.gov/projects/bsd/ERICA%20Manuscripts%20for%20Review/KD%20Rodland%20D7E80/HMEC_transactivation_ms01_15+Figs.pdf ABSTRACT: Using a single nontransformed strain of human mammary epithelial cells, we found that the ability of multiple growth factors and cytokines to induce ERK phosphorylation was dependent on EGFR activity. These included lysophosphatidic acid (LPA), uridine triphosphate, growth hormone, vascular endothelial growth factor, insulin-like growth factor-1 (IGF-1), and tumor necrosis factoralpha. In contrast, hepatocyte growth factor could stimulate ERK phosphorylation independent of EGFR activity...

  20. [The basic and applied study on the epidermal growth factor].

    PubMed

    Huang, B R; Cai, L W; Xiang, X Z

    2001-04-01

    This article reviews the results of the basic research about epidermal growth factor and its receptor, and the development of the novel drug, EGF eyedrop, that containing chemically synthesized EGF gene, the construction of EGF expression vector, the transformation of the host cells, the purification of the recombinant protein EGF, the preparation of three batches of the EGF product and identification, the preclinical and clinical trials. Relevant studies show that recombinant EGF consisting of 51 amino acids can be secreted into the medium under the control of the alpha factor leading sequence in the yeast cells. The EGF can accelerate the growth of corneal-limbal epithelial cells and the healing of an alkali burned corneal. The EGF can be used in curing oral cavity ulcer and skin burned wound. And it has the preventive effects on experimental duodenal ulcer of rat. The antiserum was made for test of the concentration of blood EGF and urine EGF by RIA. Data from studies demonstrate the inhibition effect of EGF on the growth of tumor cells, such as A431 and BT325 cells in the presence of high EGF concentration (> 10 ng/ml). The expression of EGFR and DNA ploidy in renal carcinoma has clinical significance. Crystallization and preliminary x-ray diffraction studies of the EGF has been made. The MW of the EGF product is 6000, and the pI is about 4.6 and it has correct N-terminal amino acids sequences, immunogenicity and biological activity. There is no vestige of the DNA of the yeast cells. Animal experiments reveal that there is no cumulation of the EGF in the body, and EGF can promote corneal epithelial healing. There is no toxicological effect during cornea wound healing of rabbit. A randomized, double-blind, placebo-controlled, multi-center clinical trial was conducted in four hospitals to assess safety, ocular tolerance and efficacy of an ophthalmic solution of EGF for 200 cases of cornea transplantation and 247 cases of nebulae. Unequivocal results were obtained as the eyedrop really accelerate the wounded cornea healing. So, the EGF eyedrop as a novel drug of class I is approved by the National Drug Administration, and this is the first gene engineering drug that come from yeast expression system in China. PMID:12905898

  1. Research Advances in Tissue Engineering Materials for Sustained Release of Growth Factors

    PubMed Central

    Zhao, Hai-yang; Wu, Jiang; Zhu, Jing-jing; Xiao, Ze-cong; He, Chao-chao; Shi, Hong-xue; Li, Xiao-kun; Yang, Shu-lin; Xiao, Jian

    2015-01-01

    Growth factors are a class of cytokines that stimulate cell growth and are widely used in clinical practice, such as wound healing, revascularization, bone repair, and nervous system disease. However, free growth factors have a short half-life and are instable in vivo. Therefore, the search of excellent carriers to enhance sustained release of growth factors in vivo has become an area of intense research interest. The development of controlled-release systems that protect the recombinant growth factors from enzymatic degradation and provide sustained delivery at the injury site during healing should enhance the growth factor's application in tissue regeneration. Thus, this study reviews current research on commonly used carriers for sustained release of growth factors and their sustained release effects for preservation of their bioactivity and their accomplishment in tissue engineering approaches. PMID:26347885

  2. Research Advances in Tissue Engineering Materials for Sustained Release of Growth Factors.

    PubMed

    Zhao, Hai-yang; Wu, Jiang; Zhu, Jing-jing; Xiao, Ze-cong; He, Chao-chao; Shi, Hong-xue; Li, Xiao-kun; Yang, Shu-lin; Xiao, Jian

    2015-01-01

    Growth factors are a class of cytokines that stimulate cell growth and are widely used in clinical practice, such as wound healing, revascularization, bone repair, and nervous system disease. However, free growth factors have a short half-life and are instable in vivo. Therefore, the search of excellent carriers to enhance sustained release of growth factors in vivo has become an area of intense research interest. The development of controlled-release systems that protect the recombinant growth factors from enzymatic degradation and provide sustained delivery at the injury site during healing should enhance the growth factor's application in tissue regeneration. Thus, this study reviews current research on commonly used carriers for sustained release of growth factors and their sustained release effects for preservation of their bioactivity and their accomplishment in tissue engineering approaches. PMID:26347885

  3. Selenoprotein W controls epidermal growth factor receptor surface expression, activation and degradation via receptor ubiquitination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Epidermal growth factor (EGF) receptor (EGFR) is the founding member of the ErbB family of growth factor receptors that modulate a complex network of intracellular signaling pathways controlling growth, proliferation and differentiation. Selenoprotein W (SEPW1) is a diet-regulated, highly conserved...

  4. Effects of methyl paraben on skin keratinocytes.

    PubMed

    Ishiwatari, S; Suzuki, T; Hitomi, T; Yoshino, T; Matsukuma, S; Tsuji, T

    2007-01-01

    Some ingredients of dermatological formulations result in skin irritation and allergy. In particular, preservatives have been reported extensively as a cause of allergic contact dermatitis. The study focused on parabens which have been used extensively as antimicrobial preservatives in foods, drugs and cosmetics. The aim of this study was to clarify the effects of the daily use of methyl paraben (MP) on human skin. The concentrations of MP in the stratum corneum (SC) of the human forearm were measured using the cup method and GC-MS after daily applications of MP containing formulations. The study also investigated the effects of long-term exposure to MP on keratinocytes in vitro. Normal human keratinocytes and the skin equivalents were cultured in the medium containing MP. The following changes were analysed: proliferating ability, apoptotic cells, morphological changes, mRNA and protein expressions. After 1 month of daily applications of MP containing formulations, MP remained unmetabolized and persisted slightly in the SC. MP decreased the proliferating ability of keratinocytes and changed the cell morphology. MP also decreased the expressions of hyaluronan synthase 1 and 2 mRNAs and type IV collagen. In contrast, it increased the expressions of involucrin and HSP27. Furthermore, MP influenced the epidermal differentiation of the skin equivalent. These results suggest that MP exposure through application of dermatological formulations results in MP persistence and accumulation in the SC, and that MP might influence the aging and differentiation of keratinocytes. PMID:17186576

  5. Distinct epidermal keratinocytes respond to extremely low-frequency electromagnetic fields differently.

    PubMed

    Huang, Chao-Ying; Chuang, Chun-Yu; Shu, Wun-Yi; Chang, Cheng-Wei; Chen, Chaang-Ray; Fan, Tai-Ching; Hsu, Ian C

    2014-01-01

    Following an increase in the use of electric appliances that can generate 50 or 60 Hz electromagnetic fields, concerns have intensified regarding the biological effects of extremely low-frequency electromagnetic fields (ELF-EMFs) on human health. Previous epidemiological studies have suggested the carcinogenic potential of environmental exposure to ELF-EMFs, specifically at 50 or 60 Hz. However, the biological mechanism facilitating the effects of ELF-EMFs remains unclear. Cellular studies have yielded inconsistent results regarding the biological effects of ELF-EMFs. The inconsistent results might have been due to diverse cell types. In our previous study, we indicated that 1.5 mT, 60 Hz ELF-EMFs will cause G1 arrest through the activation of the ATM-Chk2-p21 pathway in human keratinocyte HaCaT cells. The aim of the current study was to investigate whether ELF-EMFs cause similar effects in a distinct epidermal keratinocyte, primary normal human epidermal keratinocytes (NHEK), by using the same ELF-EMF exposure system and experimental design. We observed that ELF-EMFs exerted no effects on cell growth, cell proliferation, cell cycle distribution, and the activation of ATM signaling pathway in NHEK cells. We demonstrated that the 2 epidermal keratinocytes responded to ELF-EMFs differently. To further validate this finding, we simultaneously exposed the NHEK and HaCaT cells to ELF-EMFs in the same incubator for 168 h and observed the cell growths. The simultaneous exposure of the two cell types results showed that the NHEK and HaCaT cells exhibited distinct responses to ELF-EMFs. Thus, we confirmed that the biological effects of ELF-EMFs in epidermal keratinocytes are cell type specific. Our findings may partially explain the inconsistent results of previous studies when comparing results across various experimental models. PMID:25409520

  6. Distinct Epidermal Keratinocytes Respond to Extremely Low-Frequency Electromagnetic Fields Differently

    PubMed Central

    Huang, Chao-Ying; Chuang, Chun-Yu; Shu, Wun-Yi; Chang, Cheng-Wei; Chen, Chaang-Ray; Fan, Tai-Ching; Hsu, Ian C.

    2014-01-01

    Following an increase in the use of electric appliances that can generate 50 or 60 Hz electromagnetic fields, concerns have intensified regarding the biological effects of extremely low-frequency electromagnetic fields (ELF-EMFs) on human health. Previous epidemiological studies have suggested the carcinogenic potential of environmental exposure to ELF-EMFs, specifically at 50 or 60 Hz. However, the biological mechanism facilitating the effects of ELF-EMFs remains unclear. Cellular studies have yielded inconsistent results regarding the biological effects of ELF-EMFs. The inconsistent results might have been due to diverse cell types. In our previous study, we indicated that 1.5 mT, 60 Hz ELF-EMFs will cause G1 arrest through the activation of the ATM-Chk2-p21 pathway in human keratinocyte HaCaT cells. The aim of the current study was to investigate whether ELF-EMFs cause similar effects in a distinct epidermal keratinocyte, primary normal human epidermal keratinocytes (NHEK), by using the same ELF-EMF exposure system and experimental design. We observed that ELF-EMFs exerted no effects on cell growth, cell proliferation, cell cycle distribution, and the activation of ATM signaling pathway in NHEK cells. We demonstrated that the 2 epidermal keratinocytes responded to ELF-EMFs differently. To further validate this finding, we simultaneously exposed the NHEK and HaCaT cells to ELF-EMFs in the same incubator for 168 h and observed the cell growths. The simultaneous exposure of the two cell types results showed that the NHEK and HaCaT cells exhibited distinct responses to ELF-EMFs. Thus, we confirmed that the biological effects of ELF-EMFs in epidermal keratinocytes are cell type specific. Our findings may partially explain the inconsistent results of previous studies when comparing results across various experimental models. PMID:25409520

  7. Purification and characterisation of a growth factor from porcine bone.

    PubMed

    Mayer, H; Kukoschke, K G

    1989-05-01

    A growth factor was extracted from porcine bone matrix by demineralisation and purified by heat and acid treatment, hydroxyapatite chromatography and gel filtration under dissociative conditions and reverse-phase HPLC. Using the mitogenic response of osteoblast-progenitor cells from embryonic chicken, a mitogenic activity was purified 3000-fold. The mitogenic protein thus purified shows an apparent molecular mass of 13.5 kDa in both the nonreduced and reduced form on sodium dodecyl sulfate/polyacrylamide gel electrophoresis. The mitogenic activity is sensitive to proteinase K, dithiothreitol, and resistant to DNAse, RNase, heat (70 degrees C) and pH (3-10). The factor stimulates the proliferation of osteoblast-progenitor cells from embryonic chick at a concentration of 1 ng/ml. It is active on cells from skin, periosteum and sternum and has no or little activity on cells of the calvaria, intestine or kidney of embryonic chick or on mouse AKR-2B/Balb c/3T3 cell line. PMID:2540973

  8. Immunomodulatory effects of transforming growth factor-? in the liver

    PubMed Central

    Schon, Hans-Theo

    2014-01-01

    Members of the transforming growth factor-? (TGF-?) family are potent regulatory cytokines that affect multiple cell types of the immune system mediating pro-inflammatory or anti-inflammatory responses. In the liver, TGF-? is produced by a multitude of non-parenchymal liver cells including hepatic stellate cells (HSCs), liver sinusoidal endothelial cells (LSECs), Kupffer cells (KCs), and dendritic cells (DCs) as well as natural killer (NK) T cells among other hepatic lymphocytes. The effect of TGF-? on other cells is highly versatile. In concert with other soluble factors, it controls the maturation, differentiation and activity of various T cell subsets that either prevent or actuate infections, graft-versus-host reactions, immune diseases, and cancer formation. During the last decades, it became evident that some TGFB1 polymorphisms are associated with the pathogenesis of hepatic disease and that plasma TGF-? is a suitable biomarker to detect liver lesions. Moreover, since TGF-? has capacity to influence the quantity and quality of T cell subsets as well as their activity, it is obvious that a well-balanced TGF-? activity is essential for liver homeostasis. In the present review, we highlight some pivotal functions of TGF-? in hepatic immunobiology. We discuss its regulatory function on adaptive immunity, the impact on differentiation of various T cell subsets, its crosstalk with Toll like receptor signaling, and its contribution to functional impairment of the liver. PMID:25568862

  9. Connective tissue growth factor induces cardiac hypertrophy through Akt signaling

    SciTech Connect

    Hayata, Nozomi; Fujio, Yasushi; Yamamoto, Yasuhiro; Iwakura, Tomohiko; Obana, Masanori; Takai, Mika; Mohri, Tomomi; Nonen, Shinpei; Maeda, Makiko; Azuma, Junichi

    2008-05-30

    In the process of cardiac remodeling, connective tissue growth factor (CTGF/CCN2) is secreted from cardiac myocytes. Though CTGF is well known to promote fibroblast proliferation, its pathophysiological effects in cardiac myocytes remain to be elucidated. In this study, we examined the biological effects of CTGF in rat neonatal cardiomyocytes. Cardiac myocytes stimulated with full length CTGF and its C-terminal region peptide showed the increase in cell surface area. Similar to hypertrophic ligands for G-protein coupled receptors, such as endothelin-1, CTGF activated amino acid uptake; however, CTGF-induced hypertrophy is not associated with the increased expression of skeletal actin or BNP, analyzed by Northern-blotting. CTGF treatment activated ERK1/2, p38 MAPK, JNK and Akt. The inhibition of Akt by transducing dominant-negative Akt abrogated CTGF-mediated increase in cell size, while the inhibition of MAP kinases did not affect the cardiac hypertrophy. These findings indicate that CTGF is a novel hypertrophic factor in cardiac myocytes.

  10. Roles of Vascular Endothelial Growth Factor in Amyotrophic Lateral Sclerosis

    PubMed Central

    Pronto-Laborinho, Ana Catarina; Pinto, Susana; de Carvalho, Mamede

    2014-01-01

    Amyotrophic lateral sclerosis (ALS) is a fatal devastating neurodegenerative disorder, involving progressive degeneration of motor neurons in spinal cord, brainstem, and motor cortex. Riluzole is the only drug approved in ALS but it only confers a modest improvement in survival. In spite of a high number of clinical trials no other drug has proved effectiveness. Recent studies support that vascular endothelial growth factor (VEGF), originally described as a key angiogenic factor, also plays a key role in the nervous system, including neurogenesis, neuronal survival, neuronal migration, and axon guidance. VEGF has been used in exploratory clinical studies with promising results in ALS and other neurological disorders. Although VEGF is a very promising compound, translating the basic science breakthroughs into clinical practice is the major challenge ahead. VEGF-B, presenting a single safety profile, protects motor neurons from degeneration in ALS animal models and, therefore, it will be particularly interesting to test its effects in ALS patients. In the present paper the authors make a brief description of the molecular properties of VEGF and its receptors and review its different features and therapeutic potential in the nervous system/neurodegenerative disease, particularly in ALS. PMID:24987705

  11. Experimental Myocardial Infarction Upregulates Circulating Fibroblast Growth Factor-23.

    PubMed

    Andrukhova, Olena; Slavic, Svetlana; Odörfer, Kathrin I; Erben, Reinhold G

    2015-10-01

    Myocardial infarction (MI) is a major cause of death worldwide. Epidemiological studies have linked vitamin D deficiency to MI incidence. Because fibroblast growth factor-23 (FGF23) is a master regulator of vitamin D hormone production and has been shown to be associated with cardiac hypertrophy per se, we explored the hypothesis that FGF23 may be a previously unrecognized pathophysiological factor causally linked to progression of cardiac dysfunction post-MI. Here, we show that circulating intact Fgf23 was profoundly elevated, whereas serum vitamin D hormone levels were suppressed, after induction of experimental MI in rat and mouse models, independent of changes in serum soluble Klotho or serum parathyroid hormone. Both skeletal and cardiac expression of Fgf23 was increased after MI. Although the molecular link between the cardiac lesion and circulating Fgf23 concentrations remains to be identified, our study has uncovered a novel heart-bone-kidney axis that may have important clinical implications and may inaugurate the new field of cardio-osteology. © 2015 American Society for Bone and Mineral Research. PMID:25858796

  12. Fibroblast growth factor 23 and acute kidney injury.

    PubMed

    Neyra, Javier A; Moe, Orson W; Hu, Ming Chang

    2015-11-01

    Fibroblast growth factor 23 (FGF23), which is produced in bone, participates in the maintenance of phosphate metabolism and can serve as a biomarker for adverse cardiovascular outcomes in patients with chronic kidney disease and end-stage renal disease. Circulating FGF23 rapidly increases after acute kidney injury (AKI), preceding other known markers such as neutrophil gelatinase-associated lipocalin and serum creatinine. The increase in FGF23 in AKI appears to be independent of parathyroid hormone, vitamin D signaling pathways, and dietary phosphate. The potential mechanisms include: (1) increased production of FGF23 in the bone by yet-to-be-identified factors; (2) ectopic production of FGF23 by injured renal tubules; and (3) decreased renal clearance of circulating FGF23. Circulating FGF23 determined by intact FGF23 enzyme-linked immunosorbent assay (ELISA) is a more reliable biomarker of AKI than FGF23 C-terminal ELISA (a mixed readout of C-terminal fragment and intact FGF23). Given that FGF23 can be ectopically expressed in differentiated renal tubules and iron modulates FGF23 metabolism, an effect of iron on FGF23 expression in renal tubules is conceivable but remains to be confirmed. More clinical and experimental studies are required to validate the use of circulating FGF23 as a biomarker for the early identification of AKI and prediction of short- and long-term adverse outcomes post-AKI. More importantly, the biologic effect of increased FGF23 in AKI needs to be defined. PMID:25480729

  13. Placental Induced Growth Factor (PIGf) in Coronary Artery Disease

    NASA Technical Reports Server (NTRS)

    Sundaresan, Alamelu; Carabello, Blaise; Mehta, Satish; Schlegel, Todd; Pellis, Neal; Ott, Mark; Pierson, Duane

    2010-01-01

    Our previous studies on normal human lymphocytes have shown a five-fold increase (p less than 0.001) in angiogenic inducers such as Placental Induced Growth Factor (PIGf) in physiologically stressful environments such as modeled microgravity, a space analog. This suggests de-regulation of cardiovascular signalling pathways indicated by upregulation of PIGf. In the current study, we measured PIGf in the plasma of 33 patients with and without coronary artery disease (CAD) to investigate whether such disease is associated with increased levels of PIGf. A control consisting of 31 sex matched apparently healthy subjects was also included in the study. We observed that the levels of PIGf in CAD patients were significantly increased compared to those in healthy control subjects (p less than 0.001) and usually increased beyond the clinical threshold level (greater than 27ng/L). The mechanisms leading to up-regulation of angiogenic factors and the adaptation of organisms to stressful environments such as isolation, high altitude, hypoxia, ischemia, microgravity, increased radiation, etc are presently unknown and require further investigation in spaceflight and these other physiologically stressed environments.

  14. Neutrino Mass, Dark Energy, and the Linear Growth Factor

    E-print Network

    Angeliki Kiakotou; Oystein Elgaroy; Ofer Lahav

    2008-03-28

    We study the degeneracies between neutrino mass and dark energy as they manifest themselves in cosmological observations. In contradiction to a popular formula in the literature, the suppression of the matter power spectrum caused by massive neutrinos is not just a function of the ratio of neutrino to total mass densities f_nu=Omega_nu/Omega_m, but also each of the densities independently. We also present a fitting formula for the logarithmic growth factor of perturbations in a flat universe, f(z, k;f_nu,w,Omega_DE)= (1-A(k)*Omega_DE*f_nu+B(k)*f_nu^2-C(k)*f_nu^3)*Omega_m(z)^alpha, where alpha depends on the dark energy equation of state parameter w. We then discuss cosmological probes where the f factor directly appears: peculiar velocities, redshift distortion and the Intergrated Sachs-Wolfe effect. We also modify the approximation of Eisenstein & Hu (1999) for the power spectrum of fluctuations in the presence of massive neutrinos and provide a revised code (http://www.star.ucl.ac.uk/~lahav/nu_matter_power.f)

  15. Tumorigenic conversion of immortal human skin keratinocytes (HaCaT) by elevated temperature.

    PubMed

    Boukamp, P; Popp, S; Bleuel, K; Tomakidi, E; Bürkle, A; Fusenig, N E

    1999-10-01

    UV-radiation is a major risk factor for non-melanoma skin cancer causing specific mutations in the p53 tumor suppressor gene and other genetic aberrations. We here propose that elevated temperature, as found in sunburn areas, may contribute to skin carcinogenesis as well. Continuous exposure of immortal human HaCaT skin keratinocytes (possessing UV-type p53 mutations) to 40 degrees C reproducibly resulted in tumorigenic conversion and tumorigenicity was stably maintained after recultivation of the tumors. Growth at 40 degrees C was correlated with the appearance of PARP, an enzyme activated by DNA strand breaks and the level corresponded to that seen after 5 Gy gamma-radiation. Concomitantly, comparative genomic hybridization (CGH) analyis demonstrated that chromosomal gains and losses were present in cells maintained at 40 degrees C while largely absent at 37 degrees C. Besides individual chromosomal aberrations, all tumor-derived cells showed gain of chromosomal material on 11q with the smallest common region being 11q13.2 to q14.1. Cyclin D1, a candidate gene of that region was overexpressed in all tumor-derived cells but cyclinD1/cdk4/cdk6 kinase activity was not increased. Thus, these data demonstrate that long-term thermal stress is a potential carcinogenic factor in this relevant skin cancer model, mediating its effect through induction of genetic instability which results in selection of tumorigenic cells characterized by gain of 11q. PMID:10523843

  16. p53 and TAp63 Promote Keratinocyte Proliferation and Differentiation in Breeding Tubercles of the Zebrafish

    PubMed Central

    Fischer, Boris; Metzger, Manuel; Richardson, Rebecca; Knyphausen, Philipp; Ramezani, Thomas; Franzen, Rainer; Schmelzer, Elmon; Bloch, Wilhelm; Carney, Thomas J.; Hammerschmidt, Matthias

    2014-01-01

    p63 is a multi-isoform member of the p53 family of transcription factors. There is compelling genetic evidence that ?Np63 isoforms are needed for keratinocyte proliferation and stemness in the developing vertebrate epidermis. However, the role of TAp63 isoforms is not fully understood, and TAp63 knockout mice display normal epidermal development. Here, we show that zebrafish mutants specifically lacking TAp63 isoforms, or p53, display compromised development of breeding tubercles, epidermal appendages which according to our analyses display more advanced stratification and keratinization than regular epidermis, including continuous desquamation and renewal of superficial cells by derivatives of basal keratinocytes. Defects are further enhanced in TAp63/p53 double mutants, pointing to partially redundant roles of the two related factors. Molecular analyses, treatments with chemical inhibitors and epistasis studies further reveal the existence of a linear TAp63/p53->Notch->caspase 3 pathway required both for enhanced proliferation of keratinocytes at the base of the tubercles and their subsequent differentiation in upper layers. Together, these studies identify the zebrafish breeding tubercles as specific epidermal structures sharing crucial features with the cornified mammalian epidermis. In addition, they unravel essential roles of TAp63 and p53 to promote both keratinocyte proliferation and their terminal differentiation by promoting Notch signalling and caspase 3 activity, ensuring formation and proper homeostasis of this self-renewing stratified epithelium. PMID:24415949

  17. Human corpus luteum: presence of epidermal growth factor receptors and binding characteristics

    SciTech Connect

    Ayyagari, R.R.; Khan-Dawood, F.S.

    1987-04-01

    Epidermal growth factor receptors are present in many reproductive tissues but have not been demonstrated in the human corpus luteum. To determine the presence of epidermal growth factor receptors and its binding characteristics, we carried out studies on the plasma cell membrane fraction of seven human corpora lutea (days 16 to 25) of the menstrual cycle. Specific epidermal growth factor receptors were present in human corpus luteum. Insulin, nerve growth factor, and human chorionic gonadotropin did not competitively displace epidermal growth factor binding. The optimal conditions for corpus luteum-epidermal growth factor receptor binding were found to be incubation for 2 hours at 4 degrees C with 500 micrograms plasma membrane protein and 140 femtomol /sup 125/I-epidermal growth factor per incubate. The number (mean +/- SEM) of epidermal growth factor binding sites was 12.34 +/- 2.99 X 10(-19) mol/micrograms protein; the dissociation constant was 2.26 +/- 0.56 X 10(-9) mol/L; the association constant was 0.59 +/- 0.12 X 10(9) L/mol. In two regressing corpora lutea obtained on days 2 and 3 of the menstrual cycle, there was no detectable specific epidermal growth factor receptor binding activity. Similarly no epidermal growth factor receptor binding activity could be detected in ovarian stromal tissue. Our findings demonstrate that specific receptors for epidermal growth factor are present in the human corpus luteum. The physiologic significance of epidermal growth factor receptors in human corpus luteum is unknown, but epidermal growth factor may be involved in intragonadal regulation of luteal function.

  18. Mechanisms of impaired nephrogenesis with fetal growth restriction: altered renal transcription and growth factor expression

    PubMed Central

    Abdel-Hakeem, Ahmed K; Henry, Tasmia Q; Magee, Thomas R; Desai, Mina; Ross, Michael; Mansano, Roy; Torday, John; Nast, Cynthia C.

    2010-01-01

    Objective Maternal food restriction during pregnancy results in growth restricted newborns and reduced glomerular number, contributing to programmed offspring hypertension. We investigated whether reduced nephrogenesis may be programmed by dysregulation of factors controlling ureteric bud branching and mesenchyme to epithelial transformation. Study Design 10 to 20 days gestation, Sprague Dawley pregnant rats (n=6/group) received ad libitum food; FR rats were 50% food restricted. At embryonic day 20, mRNA and protein expression of WT1, Pax2, FGF2, GDNF, cRET, WNT4, WNT11, BMP4, BMP7, and FGF7 were determined by real-time PCR and Western blotting. Results Maternal FR resulted in up-regulated mRNA expression for WT1, FGF2, and BMP7 whereas Pax2, GDNF, FGF7, BMP4, WNT4, and WNT11 mRNAs were down-regulated. Protein expression was concordant for WT1, GDNF, Pax2, FGF7, BMP4 and WNT4. Conclusion Maternal FR altered gene expression of fetal renal transcription and growth factors, and likely contributes to development of offspring hypertension. PMID:18639218

  19. Xylan-regulated Delivery of Human Keratinocyte Growth Factor-2 to the Inflamed Colon by the Human Anaerobic Commensal Bacterium Bacteroides ovatus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of genetically modified bacteria to deliver biologically active molecules directly to the gut has become an increasingly attractive area of investigation. The challenge of regulation of production of the therapeutic molecule and colonization of the bowel led us to investigate Bacteroides ov...

  20. Resveratrol induces human keratinocyte damage via the activation of class III histone deacetylase, Sirt1.

    PubMed

    Lee, Ju-Hee; Kim, Jin-Shang; Park, Sang-Youel; Lee, You-Jin

    2016-01-01

    Human skin diseases are various and induce chronic inflammatory disorders, including psoriasis, atopic dermatitis and certain forms of ichthyosis. Psoriasis is a chronic inflammatory skin disease characterized by circumscribed, red, thickened plaques. Regulation of the balance between growth, differentiation and death is critical to keratinocytes; when altered, epidermal keratinocytes undergo hyperproliferation, abnormal differentiation and inflammatory infiltration. In the present study, we focused on the effects of resveratrol, found in red wine and peanuts, on the cell death of keratinocytes. We additionally studied the mechanism of resveratrol on Sirt1, a class III histone deacetylase, and Akt phosphorylation. Resveratrol caused apoptosis and increased Sirt1 expression in human HaCaT keratinocytes, following a decrease in the p62 protein level. Inhibition of Sirt1 by Sirt1 inhibitor restored cell viability and protein levels. Furthermore, we showed that resveratrol-induced Sirt1 blocked Akt phosphorylation. The present results indicated that resveratrol inhibited the Akt pathways by inducing Sirt1, thus leading to cell death. These data suggest that resveratrol-mediated activation of Sirt1 histone deacetylase may be a potential therapeutic target for skin diseases including psoriasis. PMID:26499368

  1. Human vascular smooth muscle cells both express and respond to heparin-binding growth factor I (endothelial cell growth factor)

    SciTech Connect

    Winkles, J.A.; Friesel, R.; Burgess, W.H.; Howk, R.; Mehlman, T.; Weinstein, R.; Maciag, T.

    1987-10-01

    The control of vascular endothelial and muscle cell proliferation is important in such processes as tumor angiogenesis, wound healing, and the pathogenesis of atherosclerosis. Class I heparin-binding growth factor (HBGF-I) is a potent mitogen and chemoattractant for human endothelial cells in vitro and will induce angiogenesis in vivo. RNA gel blot hybridization experiments demonstrate that cultured human vascular smooth muscle cells, but not human umbilical cells also synthesize an HBGF-I mRNA. Smooth muscle cells also synthesize an HBGF-I-like polypeptide since (i) extract prepared from smooth muscle cells will compete with /sup 125/I-labeled HBGF-I for binding to the HBGF-I cell surface receptor, and (ii) the competing ligand is eluted from heparin-Sepharose affinity resin at a NaCl concentration similar to that required by purified bovine brain HBGF-I and stimulates endothelial cell proliferation in vitro. Furthermore, like endothelial cells, smooth muscle cells possess cell-surface-associated HBGF-I receptors and respond to HBGF-I as a mitogen. These results indicate the potential for an additional autocrine component of vascular smooth muscle cell growth control and establish a vessel wall source of HBGF-I for endothelial cell division in vivo.

  2. Fibroblast Growth Factor 10-Fibroblast Growth Factor Receptor 2b Mediated Signaling Is Not Required for Adult Glandular Stomach Homeostasis

    PubMed Central

    Sala, Frederic G.; Ford, Henri R.; Bellusci, Saverio; Grikscheit, Tracy C.

    2012-01-01

    The signaling pathways that are essential for gastric organogenesis have been studied in some detail; however, those that regulate the maintenance of the gastric epithelium during adult homeostasis remain unclear. In this study, we investigated the role of Fibroblast growth factor 10 (FGF10) and its main receptor, Fibroblast growth factor receptor 2b (FGFR2b), in adult glandular stomach homeostasis. We first showed that mouse adult glandular stomach expressed Fgf10, its receptors, Fgfr1b and Fgfr2b, and most of the other FGFR2b ligands (Fgf1, Fgf7, Fgf22) except for Fgf3 and Fgf20. Fgf10 expression was mesenchymal whereas FGFR1 and FGFR2 expression were mostly epithelial. Studying double transgenic mice that allow inducible overexpression of Fgf10 in adult mice, we showed that Fgf10 overexpression in normal adult glandular stomach increased epithelial proliferation, drove mucous neck cell differentiation, and reduced parietal and chief cell differentiation. Although a similar phenotype can be associated with the development of metaplasia, we found that Fgf10 overexpression for a short duration does not cause metaplasia. Finally, investigating double transgenic mice that allow the expression of a soluble form of Fgfr2b, FGF10's main receptor, which acts as a dominant negative, we found no significant changes in gastric epithelial proliferation or differentiation in the mutants. Our work provides evidence, for the first time, that the FGF10-FGFR2b signaling pathway is not required for epithelial proliferation and differentiation during adult glandular stomach homeostasis. PMID:23133671

  3. Effects of 530 nm monochromatic light on basic fibroblast growth factor and transforming growth factor-?1 expression in Müller cells

    PubMed Central

    Fu, Xin-Yi; Zhang, Xiao-Feng; Xia, Wei; Zhong, Lei; Wang, Ying-Ming; Sun, Zheng-Tai; Xia, Jing

    2015-01-01

    AIM To expose rat retinal Müller cells to 530 nm monochromatic light and investigate the influence of varying light illumination times on basic fibroblast growth factor (bFGF) and transforming growth factor-?1 (TGF-?1) expression. METHODS Three groups of rat retinal Müller cells cultured in vitro under a 530 nm monochromatic light were divided into 6, 12 and 24h experimental groups, while cells incubated under dark conditions served as the control group. The bFGF and TGF-?1 mRNA expression, protein levels and fluorescence intensity of the Müller cells were analyzed. RESULTS The bFGF mRNA expression and protein levels were significantly upregulated in Müller cells in all three experimental groups compared with the control group (P<0.05), while that of TGF-?1 was downregulated (P<0.05). Also, bFGF expression was positively correlated, but TGF-?1 expression was negatively correlated with illumination time. The largest changes for both cytokines were seen in the 24h group. The changes in bFGF and TGF-?1 fluorescence intensity were highest in the 24h group, and significant differences were observed among the experimental groups (P<0.05). CONCLUSION The expressions of bFGF and TGF-?1 changed in a time-dependent manner in Müller cells exposed to 530 nm monochromatic light with 250 lx illumination intensity. Müller cells might play a role in the development of myopia by increasing bFGF expression or decreasing TGF-?1 expression. Changes in cytokine expression in retinal Müller cells may affect monochromatic light-induced myopia. PMID:26558199

  4. Connective tissue growth factor/CCN2-null mouse embryonic fibroblasts retain intact transforming growth factor-{beta} responsiveness

    SciTech Connect

    Mori, Yasuji; Hinchcliff, Monique; Wu, Minghua; Warner-Blankenship, Matthew; Lyons, Karen M.

    2008-03-10

    Background: The matricellular protein connective tissue growth factor (CCN2) has been implicated in pathological fibrosis, but its physiologic role remains elusive. In vitro, transforming growth factor-{beta} (TGF-{beta}) induces CCN2 expression in mesenchymal cells. Because CCN2 can enhance profibrotic responses elicited by TGF-{beta}, it has been proposed that CCN2 functions as an essential downstream signaling mediator for TGF-{beta}. To explore this notion, we characterized TGF-{beta}-induced activation of fibroblasts from CCN2-null (CCN2{sup -/-}) mouse embryos. Methods: The regulation of CCN2 expression was examined in vivo in a model of fibrosis induced by bleomycin. Cellular TGF-{beta} signal transduction and regulation of collagen gene expression were examined in CCN2{sup -/-} MEFs by immunohistochemistry, Northern, Western and RT-PCR analysis, immunocytochemistry and transient transfection assays. Results: Bleomycin-induced skin fibrosis in the mouse was associated with substantial CCN2 up-regulation in lesional fibroblasts. Whereas in vitro proliferation rate of CCN2{sup -/-} MEFs was markedly reduced compared to wild type MEFs, TGF-{beta}-induced activation of the Smad pathways, including Smad2 phosphorylation, Smad2/3 and Smad4 nuclear accumulation and Smad-dependent transcriptional responses, were unaffected by loss of CCN2. The stimulation of COL1A2 and fibronectin mRNA expression and promoter activity, and of corresponding protein levels, showed comparable time and dose-response in wild type and CCN2{sup -/-} MEFs, whereas stimulation of alpha smooth muscle actin and myofibroblast transdifferentiation showed subtle impairment in MEFs lacking CCN2. Conclusion: Whereas endogenous CCN2 plays a role in regulation of proliferation and TGF-{beta}-induced myofibroblast transdifferentiation, it appears to be dispensable for Smad-dependent stimulation of collagen and extracellular matrix synthesis in murine embryonic fibroblasts.

  5. A novel monoclonal antibody to fibroblast growth factor 2 effectively inhibits growth of hepatocellular carcinoma xenografts.

    PubMed

    Wang, Lihong; Park, Hangil; Chhim, Sophea; Ding, Yi; Jiang, Wei; Queen, Cary; Kim, K Jin

    2012-04-01

    Expression of fibroblast growth factor 2 (FGF2) is believed to be a contributing factor to the growth of a number of tumor types, including hepatocellular carcinoma (HCC). However, the potential of monoclonal antibodies that neutralize FGF2 for treatment of patients with cancer has not yet been explored in clinical trials. We therefore generated a novel monoclonal antibody (mAb), GAL-F2, specific for FGF2 and characterized its properties in vitro and in vivo. GAL-F2 binds to a different epitope than several previous anti-FGF2 mAbs tested. This novel epitope was defined using chimeric FGF1/FGF2 proteins and alanine scanning mutagenesis and was shown to comprise amino acids in both the amino and carboxy regions of FGF2. GAL-F2 blocked binding of FGF2 to each of its four cellular receptors, strongly inhibited FGF2-induced proliferation and downstream signaling in human umbilical vein endothelial cells, and inhibited proliferation and downstream signaling in two HCC cell lines. Moreover, GAL-F2, administered at 5 mg/kg i.p. twice weekly, potently inhibited growth of xenografts of the SMMC-7721, HEP-G2, and SK-HEP-1 human HCC cell lines in nude mice, and in some models, had a strong additive effect with an anti-VEGF mAb or sorafenib. Treatment with GAL-F2 also blocked angiogenesis and inhibited downstream cellular signaling in xenografts, indicating its antitumor mechanism of action. Our report supports clinical testing of a humanized form of the GAL-F2 mAb for treatment of HCC and potentially other cancers. PMID:22351746

  6. A Novel Monoclonal Antibody to Fibroblast Growth Factor 2 Effectively Inhibits Growth of Hepatocellular Carcinoma Xenografts

    PubMed Central

    Wang, Lihong; Park, Hangil; Chhim, Sophea; Ding, Yi; Jiang, Wei; Queen, Cary; Kim, K. Jin

    2012-01-01

    Expression of Fibroblast Growth Factor 2 (FGF2) is believed to be a contributing factor to the growth of a number of tumor types, including hepatocellular carcinoma (HCC). However, the potential of monoclonal antibodies that neutralize FGF2 for treatment of cancer patients has not yet been explored in clinical trials. We therefore generated a novel monoclonal antibody (mAb), GAL-F2, specific for FGF2 and characterized its properties in vitro and in vivo. GAL-F2 binds to a different epitope than several previous anti-FGF2 mAbs tested: this novel epitope was defined using chimeric FGF1/FGF2 proteins and alanine scanning mutagenesis and shown to comprise amino acids in both the amino and carboxy regions of FGF2. GAL-F2 blocked binding of FGF2 to each of its four cellular receptors, strongly inhibited FGF2-induced proliferation and downstream signaling in HUVEC, and inhibited proliferation and downstream signaling in two HCC cell lines. Moreover, GAL-F2, administered at 5 mg/kg i.p. twice weekly, potently inhibited growth of xenografts of the SMMC-7721, HEP-G2 and SK-HEP-1 human HCC cell lines in nude mice, and in some models had a strong additive effect with an anti-VEGF mAb or sorafenib. Treatment with GAL-F2 also blocked angiogenesis and inhibited downstream cellular signaling in xenografts, indicating its anti-tumor mechanism of action. Our report supports clinical testing of a humanized form of the GAL-F2 mAb for treatment of HCC and potentially other cancers. PMID:22351746

  7. The Use of Fibroblast Growth Factor 23 Testing in Patients with Kidney Disease

    PubMed Central

    2014-01-01

    The emergence of fibroblast growth factor 23 as a potentially modifiable risk factor in CKD has led to growing interest in its measurement as a tool to assess patient risk and target therapy. This review discusses the analytical and clinical challenges faced in translating fibroblast growth factor 23 testing into routine practice. As for other bone mineral markers, agreement between commercial fibroblast growth factor 23 assays is poor, mainly because of differences in calibration, but also, these differences reflect the variable detection of hormone fragments. Direct comparison of readout from different assays is consequently limited and likely hampers setting uniform fibroblast growth factor 23–directed targets. Efforts are needed to standardize assay output to enhance clinical use. Fibroblast growth factor 23 is robustly associated with cardiovascular and renal outcomes in patients with CKD and adds value to risk assessments based on conventional risk factors. Compared with most other mineral markers, fibroblast growth factor 23 shows better intraindividual temporal stability, with minimal diurnal and week-to-week variability, but substantial interindividual variation, maximizing discriminative power for risk stratification. Conventional therapeutic interventions for the CKD–mineral bone disorder, such as dietary phosphate restriction and use of oral phosphate binders or calcimimetics, are associated with variable efficacy at modulating circulating fibroblast growth factor 23 concentrations, like they are for other mineral metabolites. Dual therapy with dietary phosphate restriction and noncalcium-based binder use achieves the most consistent fibroblast growth factor 23–lowering effect and seems best monitored using an intact assay. Additional studies are needed to evaluate whether strategies aimed at reducing levels or antagonizing its action have beneficial effects on clinical outcomes in CKD patients. Moreover, a better understanding of the mechanisms driving fibroblast growth factor 23 elevations in CKD is needed to inform the use of therapeutic interventions targeting fibroblast growth factor 23 excess. This evidence must be forthcoming to support the use of fibroblast growth factor 23 measurement and fibroblast growth factor 23–directed therapy in the clinic. PMID:24578336

  8. Liver Growth Factor as a Tissue Regenerating Factor in Neurodegenerative Diseases

    PubMed Central

    Gonzalo-Gobernado, Rafael; Calatrava-Ferreras, Lucia; Perucho, Juan; Reimers, Diana; Casarejos, María J.; Herranz, Antonio S.; Jiménez-Escrig, Adriano; Díaz-Gil, Juan J.; Bazán, Eulalia

    2014-01-01

    Liver growth factor (LGF) is a hepatic mitogen purified by our group in 1986. In the following years we demonstrated its activity both in “in vivo” and “in vitro” systems, stimulating hepatocytes mitogenesis as well as liver regeneration in several models of liver injury. Furthermore, we established its chemical composition (albumin-bilirubin complex) and its mitogenic actions in liver. From 2000 onwards we used LGF as a tissue regenerating factor in several models of extrahepatic diseases. The use of Liver growth factor as a neural tissue regenerator has been recently protected (Patent No US 2014/8,642,551 B2). LGF administration stimulates neurogenesis and neuron survival, promotes migration of newly generated neurons, and induces the outgrowth of striatal dopaminergic terminals in 6-hidroxydopamine-lesioned rats. Furthermore, LGF treatment raises striatal dopamine levels and protects dopaminergic neurons in hemiparkinsonian animals. LGF also stimulates survival of grafted foetal neural stem cells in the damaged striatum, reduces rotational behaviour and improves motor coordination. Interestingly, LGF also exerts a neuroprotective role both in an experimental model of cerebellar ataxia and in a model of Friedrich´s ataxia. Microglia seem to be the cellular target of LGF in the CNS. Moreover, the activity of the factor could be mediated by the stimulation of MAPK´s signalling pathway and by regulating critical proteins for cell survival, such as Bcl-2 and phospho-CREB. Since the factor shows neuroprotective and neurorestorative effects we propose LGF as a patented novel therapeutic tool that may be useful for the treatment of Parkinson´s disease and cerebellar ataxias. Currently, our studies have been extended to other neurological disorders such as Alzheimer’s disease (Patent No: US 2014/0113859 A1). PMID:25537484

  9. Fibroblast growth factor receptor 3-IIIc mediates colorectal cancer growth and migration

    PubMed Central

    Sonvilla, G; Allerstorfer, S; Heinzle, C; Stättner, S; Karner, J; Klimpfinger, M; Wrba, F; Fischer, H; Gauglhofer, C; Spiegl-Kreinecker, S; Grasl-Kraupp, B; Holzmann, K; Grusch, M; Berger, W; Marian, B

    2010-01-01

    Background: Deregulation of fibroblast growth factor receptor 3 (FGFR3) is involved in several malignancies. Its role in colorectal cancer has not been assessed before. Methods: Expression of FGFR3 in human colorectal tumour specimens was analysed using splice variant-specific real-time reverse transcriptase PCR assays. To analyse the impact of FGFR3-IIIc expression on tumour cell biology, colon cancer cell models overexpressing wild-type (WT-3b and WT3c) or dominant-negative FGFR3 variants (KD3c and KD3b) were generated by either plasmid transfection or adenoviral transduction. Results: Although FGFR3 mRNA expression is downregulated in colorectal cancer, alterations mainly affected the FGFR3-IIIb splice variant, resulting in an increased IIIc/IIIb ratio predominantly in a subgroup of advanced tumours. Overexpression of WT3c increased proliferation, survival and colony formation in all colon cancer cell models tested, whereas WT3b had little activity. In addition, it conferred sensitivity to autocrine FGF18-mediated growth and migration signals in SW480 cells with low endogenous FGFR3-IIIc expression. Disruption of FGFR3-IIIc-dependent signalling by dominant-negative FGFR3-IIIc or small interfering RNA-mediated FGFR3-IIIc knockdown resulted in inhibition of cell growth and induction of apoptosis, which could not be observed when FGFR3-IIIb was blocked. In addition, KD3c expression blocked colony formation and migration and distinctly attenuated tumour growth in SCID mouse xenograft models. Conclusion: Our data show that FGFR3-IIIc exerts oncogenic functions by mediating FGF18 effects in colorectal cancer and may constitute a promising new target for therapeutic interventions. PMID:20234367

  10. Cytotoxic effects of acrylamide in nerve growth factor or fibroblast growth factor 1-induced neurite outgrowth in PC12 cells.

    PubMed

    Chen, Jong-Hang; Lee, Don-Ching; Chiu, Ing-Ming

    2014-03-01

    Acrylamide is a neurological and reproductive toxicant in humans and laboratory animals; however, the neuron developmental toxicity of acrylamide remains unclear. The aims of this study are to investigate the cytotoxicity and neurite outgrowth inhibition of acrylamide in nerve growth factor (NGF)- or fibroblast growth factor 1 (FGF1)-mediated neural development of PC12 cells. MTS assay showed that acrylamide treatment suppresses NGF- or FGF1-induced PC12 cell proliferation in a time- and dose-dependent manner. Quantification of neurite outgrowth demonstrated that 0.5 mM acrylamide treatment resulted in significant decrease in differentiation of NGF- or FGF1-stimulated PC12 cells. This decrease is accompanied with the reduced expression of growth-associated protein-43, a neuronal marker. Moreover, relative levels of pERK, pAKT, pSTAT3 and pCREB were increased within 5-10 min when PC12 cells were treated with NGF or FGF1. Acrylamide (0.5 mM) decreases the NGF-induced activation of AKT-CREB but not ERK-STAT3 within 20 min. Similarly, acrylamide (0.5 mM) decreases the FGF1-induced activation of AKT-CREB within 20 min. In contrast to the NGF treatment, the ERK-STAT3 activation that was induced by FGF1 was slightly reduced by 0.5 mM acrylamide. We further showed that PI3K inhibitor (LY294002), but not MEK inhibitor (U0126), could synergize with acrylamide (0.5 mM) to reduce the cell viability and neurite outgrowth in NGF- or FGF1-stimulated PC12 cells. Moreover, acrylamide (0.5 mM) increased reactive oxygen species (ROS) activities in NGF- or FGF1-stimulated PC12 cells. This increase was reversed by Trolox (an ROS scavenging agent) co-treatment. Together, our findings reveal that NGF- or FGF1-stimulation of the neuronal differentiation of PC12 cells is attenuated by acrylamide through the inhibition of PI3K-AKT-CREB signaling, along with the production of ROS. PMID:24318646

  11. The Role of Docosahexaenoic Acid in Regulation of Epidermal Growth Factor Receptor Activation and Function 

    E-print Network

    Turk, Harmony 1985-

    2012-08-30

    The epidermal growth factor receptor (EGFR) is a transmembrane receptor tyrosine kinase integral in regulating cell growth, survival, and migration. EGFR signaling, which is dependent on localization of the receptor within ...

  12. Characterization and informed design of downregulating anti-epidermal growth factor receptor antibodies

    E-print Network

    Spangler, Jamie Berta

    2011-01-01

    Due to its common dysregulation in epithelial-based cancers and the extensive characterization of its role in tumor growth, epidermal growth factor receptor (EGFR) has long been an attractive target for monoclonal antibodies. ...

  13. Combination antibody treatment down-regulates epidermal growth factor receptor by inhibiting endosomal recycling

    E-print Network

    Spangler, Jamie Berta

    Due to its common dysregulation in epithelial-based cancers and extensive characterization of its role in tumor growth, epidermal growth factor receptor (EGFR) is a highly validated target for anticancer therapies. There ...

  14. Keratinocyte proliferation, differentiation, and apoptosis-Differential mechanisms of regulation by curcumin, EGCG and apigenin

    SciTech Connect

    Balasubramanian, Sivaprakasam; Eckert, Richard L.

    2007-11-01

    We have proposed that it is important to examine the impact of chemopreventive agents on the function of normal human epidermal keratinocytes since these cells comprise the barrier that protects the body from a range of environmental insults. In this context, it is widely appreciated that cancer may be retarded by consumption or topical application of naturally occurring food-derived chemopreventive agents. Our studies show that (-)-epigallocatechin-3-gallate (EGCG), a green tea-derived polyphenol, acts to enhance the differentiation of normal human keratinocytes as evidenced by its ability to increase involucrin (hINV), transglutaminase type 1 (TG1) and caspase-14 gene expression. EGCG also stimulates keratinocyte morphological differentiation. These actions of EGCG are mediated via activation of a nPKC, Ras, MEKK1, MEK3, p38{delta}-ERK1/2 signaling cascade which leads to increased activator protein 1 (AP1) and CAATT enhancer binding protein (C/EBP) transcription factor expression, increased binding of these factors to DNA, and increased gene transcription. In contrast, apigenin, a dietary flavonoid derived from plants and vegetables, and curcumin, an agent derived from turmeric, inhibit differentiation by suppressing MAPK signal transduction and reducing API transcription factor level. Curcumin also acts to enhance apoptosis, although EGCG and apigenin do not stimulate apoptosis. In addition, all of these agents inhibit keratinocyte proliferation. These findings indicate that each of these diet-derived chemopreventive agents has a profound impact on normal human keratinocyte function and that they operate via distinct and sometimes opposing mechanisms. However, all are expected to act as chemopreventive agents.

  15. Increased Serum Levels of Epidermal Growth Factor in Children with Autism

    ERIC Educational Resources Information Center

    Iseri, Elvan; Guney, Esra; Ceylan, Mehmet F.; Yucel, Aysegul; Aral, Arzu; Bodur, Sahin; Sener, Sahnur

    2011-01-01

    The etiology of autism is unclear, however autism is considered as a multifactorial disorder that is influenced by neurological, environmental, immunological and genetic factors. Growth factors, including epidermal growth factor (EGF), play an important role in the celluler proliferation and the differentiation of the central and peripheral…

  16. The Effects of Autocorrelation on the Curve-of-Factors Growth Model

    ERIC Educational Resources Information Center

    Murphy, Daniel L.; Beretvas, S. Natasha; Pituch, Keenan A.

    2011-01-01

    This simulation study examined the performance of the curve-of-factors model (COFM) when autocorrelation and growth processes were present in the first-level factor structure. In addition to the standard curve-of factors growth model, 2 new models were examined: one COFM that included a first-order autoregressive autocorrelation parameter, and a…

  17. Fibroblast growth factor receptors as molecular targets in thyroid carcinoma.

    PubMed

    St Bernard, Rosanne; Zheng, Lei; Liu, Wei; Winer, Daniel; Asa, Sylvia L; Ezzat, Shereen

    2005-03-01

    Several molecular abnormalities of potential therapeutic target value have been described in thyroid neoplastic transition. We report the expression of the fibroblast growth factor receptor family (FGFR-1-4) in normal thyroid tissues, human thyroid cancers of various types and behaviors, and cell lines representative of the spectrum of differentiation of tumors derived from follicular epithelial cells. FGFR-2 was the only receptor consistently detected in normal human thyroid tissue, and its expression diminished in all thyroid cancers and carcinoma cell lines, suggesting that it may have a protective role. FGFR-1 and FGFR-3 were expressed in most well-differentiated tumor types. FGFR-4, however, was expressed predominantly in aggressive tumor types and the most rapidly proliferative cell lines, indicating that it may promote the progression of these tumors. To specifically determine the function of FGFR-4 in thyroid carcinoma, gain- or loss-of-function studies were performed in cell lines representative of the spectrum of thyroid cancer behavior. Introduction of FGFR-4 resulted in enhanced cell proliferation, an effect that was more pronounced in cell lines derived from aggressive tumors than in those derived from more indolent neoplasms. Moreover, transduction of a dominant-negative FGFR attenuated cell proliferation in the aggressive poorly differentiated cell lines with no appreciable effect in well-differentiated cells. Pharmacologic FGFR-4 tyrosine kinase inhibition resulted in significant proliferation arrest in an aggressive cell line endogenously expressing the receptor. Furthermore, systemic administration of the FGFR tyrosine kinase inhibitor PD173074 resulted in significant inhibition of follicular thyroid carcinoma-derived cell growth in xenografted severe combined immunodeficient mice. These data indicate a role for FGFR-4 in human thyroid cancer cell progression and provide a rationale for FGFR manipulation as a potentially novel therapeutic approach. PMID:15564323

  18. Transforming growth factor-{beta}-inducible phosphorylation of Smad3.

    PubMed

    Wang, Guannan; Matsuura, Isao; He, Dongming; Liu, Fang

    2009-04-10

    Smad proteins transduce the transforming growth factor-beta (TGF-beta) signal at the cell surface into gene regulation in the nucleus. Upon TGF-beta treatment, the highly homologous Smad2 and Smad3 are phosphorylated by the TGF-beta receptor at the SSXS motif in the C-terminal tail. Here we show that in addition to the C-tail, three (S/T)-P sites in the Smad3 linker region, Ser(208), Ser(204), and Thr(179) are phosphorylated in response to TGF-beta. The linker phosphorylation peaks at 1 h after TGF-beta treatment, behind the peak of the C-tail phosphorylation. We provide evidence suggesting that the C-tail phosphorylation by the TGF-beta receptor is necessary for the TGF-beta-induced linker phosphorylation. Although the TGF-beta receptor is necessary for the linker phosphorylation, the receptor itself does not phosphorylate these sites. We further show that ERK is not responsible for TGF-beta-dependent phosphorylation of these three sites. We show that GSK3 accounts for TGF-beta-inducible Ser(204) phosphorylation. Flavopiridol, a pan-CDK inhibitor, abolishes TGF-beta-induced phosphorylation of Thr(179) and Ser(208), suggesting that the CDK family is responsible for phosphorylation of Thr(179) and Ser(208) in response to TGF-beta. Mutation of the linker phosphorylation sites to nonphosphorylatable residues increases the ability of Smad3 to activate a TGF-beta/Smad-target gene as well as the growth-inhibitory function of Smad3. Thus, these observations suggest that TGF-beta-induced phosphorylation of Smad3 linker sites inhibits its antiproliferative activity. PMID:19218245

  19. Axl Activates Autocrine Transforming Growth Factor-? Signaling in Hepatocellular Carcinoma

    PubMed Central

    Reichl, Patrick; Dengler, Mirko; van Zijl, Franziska; Huber, Heidemarie; Führlinger, Gerhard; Reichel, Christian; Sieghart, Wolfgang; Peck-Radosavljevic, Markus; Grubinger, Markus; Mikulits, Wolfgang

    2015-01-01

    In hepatocellular carcinoma (HCC), intrahepatic metastasis frequently correlates with epithelial to mesenchymal transition (EMT) of malignant hepatocytes. Several mechanisms have been identified to be essentially involved in hepatocellular EMT, among them transforming growth factor (TGF)-? signaling. Here we show the up-regulation and activation of the receptor tyrosine kinase Axl in EMT-transformed hepatoma cells. Knockdown of Axl expression resulted in abrogation of invasive and transendothelial migratory abilities of mesenchymal HCC cells in vitro and Axl overexpression-induced metastatic colonization of epithelial hepatoma cells in vivo. Importantly, Axl knockdown severely impaired resistance to TGF-?-mediated growth inhibition. Analysis of the Axl interactome revealed binding of Axl to 14-3-3?, which is essentially required for Axl-mediated cell invasion, transendothelial migration, and resistance against TGF-?. Axl/14-3-3? signaling caused phosphorylation of Smad3 linker region (Smad3L) at Ser213, resulting in the up-regulation of tumor-progressive TGF-? target genes such as PAI1, MMP9, and Snail as well as augmented TGF-?1 secretion in mesenchymal HCC cells. Accordingly, high Axl expression in HCC patient samples correlated with elevated vessel invasion of HCC cells, higher risk of tumor recurrence after liver transplantation, strong phosphorylation of Smad3L, and lower survival. In addition, elevated expression of both Axl and 14-3-3? showed strongly reduced survival of HCC patients. Conclusion Our data suggest that Axl/14-3-3? signaling is central for TGF-?-mediated HCC progression and a promising target for HCC therapy. PMID:25251599

  20. Nerve growth factor in human semen: Effect of nerve growth factor on the normozoospermic men during cryopreservation process

    PubMed Central

    Saeednia, Sara; Bahadoran, Hosein; Amidi, Fardin; Asadi, Mohammad Hosein; Naji, Mohammad; Fallahi, Parvin; Nejad, Nahid Ataie

    2015-01-01

    Objective(s): Although routinely applied in assisted reproductive technology, human sperm cryopreservation is not a completely successful procedure. Adverse effects of cryopreservation on the fertilization capacity, motility, morphology, and viability of spermatozoa have been proven; cryopreservation has also shown a role in sperm DNA fragmentation and infertility. The post-thaw survival of spermatozoa improved after addition of supplementation of antioxidant molecules to freezing media. Nerve growth factor (NGF) as one of the prosurvival substances has gained great attention in recent years. The aim of this study was the usage of NGF as prosurvival factor after cryopreservation process of human semen samples to assess the motility and viability of sperm, nitric oxide (NO) concentration, and DNA fragmentation in normozoospermic men. Materials and Methods: Semen samples were collected from 25 normozoospermic men and were divided into fresh semen samples as control group, frozen–thawed semen samples without addition of exogenous NGF, and three groups of semen samples cryopreserved with addition of exogenous NGF (0.5, 1, and 5 ng/ml) in freezing medium. Viability was assessed by eosin-negrosin staining technique. Motility was evaluated with inverted microscope. NO concentration and apoptosis content were measured with flow cytometry. Results: Results showed that exogenous NGF at 0.5 ng/ml could significantly (P-value <0.05) influence viability, motility, nitric oxide, and DNA fragmentation content. Conclusion: Exogenous NGF as cryoprotectant improved sperm viability and motility, increased intracellular NO concentration, and decreased apoptosis content in normal human spermatozoa. PMID:25945243

  1. Connective tissue growth factor is a substrate of ADAM28

    SciTech Connect

    Mochizuki, Satsuki; Tanaka, Rena; Shimoda, Masayuki; Onuma, Junko; Fujii, Yutaka; Jinno, Hiromitsu; Okada, Yasunori

    2010-11-26

    Research highlights: {yields} The hyper-variable region in the cysteine-rich domain of ADAM28 binds to C-terminal domain of CTGF. {yields} ADAM28 cleaves CTGF alone and CTGF in the CTGF/VEGF{sub 165} complex. {yields} CTGF digestion by ADAM28 releases biologically active VEGF{sub 165} from the complex. {yields} ADAM28, CTGF and VEGF{sub 165} are commonly co-expressed by carcinoma cells in human breast carcinoma tissues. {yields} These suggest that ADAM28 promotes VEGF{sub 165}-induced angiogenesis in the breast carcinomas by selective CTGF digestion in the CTGF/VEGF{sub 165} complex. -- Abstract: ADAM28, a member of the ADAM (a disintegrin and metalloproteinase) gene family, is over-expressed by carcinoma cells and the expression correlates with carcinoma cell proliferation and progression in human lung and breast carcinomas. However, information about substrates of ADAM28 is limited. We screened interacting molecules of ADAM28 in human lung cDNA library by yeast two-hybrid system and identified connective tissue growth factor (CTGF). Binding of CTGF to proADAM28 was demonstrated by yeast two-hybrid assay and protein binding assay. ADAM28 cleaved CTGF in dose- and time-dependent manners at the Ala{sup 181}-Tyr{sup 182} and Asp{sup 191}-Pro{sup 192} bonds in the hinge region of the molecule. ADAM28 selectively digested CTGF in the complex of CTGF and vascular endothelial growth factor{sub 165} (VEGF{sub 165}), releasing biologically active VEGF{sub 165} from the complex. RT-PCR and immunohistochemical analyses demonstrated that ADAM28, CTGF and VEGF are commonly co-expressed in the breast carcinoma tissues. These data provide the first evidence that CTGF is a novel substrate of ADAM28 and suggest that ADAM28 may promote VEGF{sub 165}-induced angiogenesis in the breast carcinomas by the CTGF digestion in the CTGF/VEGF{sub 165} complex.

  2. Use of autologous growth factors in lumbar spinal fusion.

    PubMed

    Lowery, G L; Kulkarni, S; Pennisi, A E

    1999-08-01

    The results of spinal fusion, especially posteriorly above the lumbosacral junction, have been mixed. Autologous growth factor concentrate (AGF) prepared by ultraconcentration of platelets contains multiple growth factors having a chemotactic and mitogenic effect on mesenchymal stem cells and osteoblasts and may play a role in initiating bone healing. The purpose of this retrospective study is to review our results with AGF in lumbar spinal fusions. To date, AGF has been used in 39 patients having lumbar spinal fusion. The study group consisted of the first 19 consecutive cases to allow at least 6 months follow-up. The average follow-up was 13 months (range 6 to 18 months). Follow-up compliance was 91%. There were 7 men and 12 women. Average age was 52 years (range 30-72 years). Nine patients had prior back surgery. There were 8 smokers. AGF was used in posterior (n = 15) or anterior intradiscal (n = 4) fusions. AGF was used with autograft and coraline hydroxyapatite in all posterior fusions, and autograft, coral, and intradiscal spacer (carbon fiber spinal fusion cages or Synthes femoral ring) in intradiscal fusions. Posterior stabilization was used in all cases. Eight cases were single-level fusions, 6 were two-level, and 1 was a three-level fusion. Autologous iliac crest bone graft was taken in 14 cases and local autograft used in 5 cases. Posteriorly, a total of 23 levels were fused; of these, nine were at L5-S1, eight at L4-L5, five at L3-L4, and one at L2-L3. No impending pseudoarthroses were noted on plain radiographic examination at last follow-up visit. Solid fusion was confirmed in 3 patients having routine hardware removal, and in 2 patients who had surgery at an adjacent level. There was one posterior wound infection, which was managed without sequelae. When used as an adjunct to autograft, AGF offers theoretical advantages that need to be examined in controlled studies. Further study is necessary to determine whether coralline hydroxyapatite used as a bone graft extender in lumbar spinal fusion may help to obviate the need for secondary site graft harvesting. PMID:10458274

  3. Bone morphogenetic protein-4 strongly potentiates growth factor-induced proliferation of mammary epithelial cells

    SciTech Connect

    Montesano, Roberto Sarkoezi, Rita; Schramek, Herbert

    2008-09-12

    Bone morphogenetic proteins (BMPs) are multifunctional cytokines that elicit pleiotropic effects on biological processes such as cell proliferation, cell differentiation and tissue morphogenesis. With respect to cell proliferation, BMPs can exert either mitogenic or anti-mitogenic activities, depending on the target cells and their context. Here, we report that in low-density cultures of immortalized mammary epithelial cells, BMP-4 did not stimulate cell proliferation by itself. However, when added in combination with suboptimal concentrations of fibroblast growth factor (FGF)-2, FGF-7, FGF-10, epidermal growth factor (EGF) or hepatocyte growth factor (HGF), BMP-4 potently enhanced growth factor-induced cell proliferation. These results reveal a hitherto unsuspected interplay between BMP-4 and growth factors in the regulation of mammary epithelial cell proliferation. We suggest that the ability of BMP-4 to potentiate the mitogenic activity of multiple growth factors may contribute to mammary gland ductal morphogenesis as well as to breast cancer progression.

  4. The scope and sequence of growth factor delivery for vascularized bone tissue regeneration.

    PubMed

    Bayer, E A; Gottardi, R; Fedorchak, M V; Little, S R

    2015-12-10

    Bone regeneration is a complex process, that in vivo, requires the highly coordinated presentation of biochemical cues to promote the various stages of angiogenesis and osteogenesis. Taking inspiration from the natural healing process, a wide variety of growth factors are currently being released within next generation tissue engineered scaffolds (in a variety of ways) in order to heal non-union fractures and bone defects. This review will focus on the delivery of multiple growth factors to the bone regeneration niche, specifically 1) dual growth factor delivery signaling and crosstalk, 2) the importance of growth factor timing and temporal separation, and 3) the engineering of delivery systems that allow for temporal control over presentation of soluble growth factors. Alternative methods for growth factor presentation, including the use of gene therapy and platelet-rich plasma scaffolds, are also discussed. PMID:26264834

  5. Some growth factors stimulate cultured adult rabbit ventricular myocyte hypertrophy in the absence of mechanical loading

    NASA Technical Reports Server (NTRS)

    Decker, R. S.; Cook, M. G.; Behnke-Barclay, M.; Decker, M. L.

    1995-01-01

    Cultured adult rabbit cardiac myocytes treated with recombinant growth factors display enhanced rates of protein accumulation (ie, growth) in response to insulin and insulin-like growth factors (IGFs), but epidermal growth factor, acidic or basic fibroblast growth factor, and platelet-derived growth factor failed to increase contractile protein synthesis or growth of the heart cells. Insulin and IGF-1 increased growth rates by stimulating anabolic while simultaneously inhibiting catabolic pathways, whereas IGF-2 elevated growth modestly by apparently inhibiting lysosomal proteolysis. Neutralizing antibodies directed against either IGF-1 or IGF-2 or IGF binding protein 3 blocked protein accumulation. A monoclonal antibody directed against the IGF-1 receptor also inhibited changes in protein turnover provoked by recombinant human IGF-1 but not IGF-2. Of the other growth factors tested, only transforming growth factor-beta 1 increased the fractional rate of myosin heavy chain (MHC) synthesis, with beta-MHC synthesis being elevated and alpha-MHC synthesis being suppressed. However, the other growth factors were able to modestly stimulate the rate of DNA synthesis in this preparation. Bromodeoxyuridine labeling revealed that these growth factors increased DNA synthesis in myocytes and nonmyocytes alike, but the heart cells displayed neither karyokinesis or cytokinesis. In contrast, cocultures of cardiac myocytes and nonmyocytes and nonmyocyte-conditioned culture medium failed to enhance the rate of cardiac MHC synthesis or its accumulation, implying that quiescent heart cells do not respond to "conditioning" by cardiac nonmyocytes. These findings demonstrated that insulin and the IGFs promote passively loaded cultured adult rabbit heart cells to hypertrophy but suggest that other growth factors tested may be limited in this regard.

  6. Monoclonal Antibodies to Fibroblast Growth Factor Receptor 2 Effectively Inhibit Growth of Gastric Tumor Xenografts

    PubMed Central

    Zhao, Wei-meng; Wang, Lihong; Park, Hangil; Chhim, Sophea; Tanphanich, Melanie; Yashiro, Masakazu; Kim, K. Jin

    2010-01-01

    Purpose Overexpression of Fibroblast Growth Factor Receptor 2 (FGFR2) may be a causative factor of a number of human tumors, especially gastric tumors of the poorly differentiated type. We investigated whether monoclonal antibodies (mAbs) directed against FGFR2 can inhibit the growth of tumors in xenograft models. Experimental Design We generated and characterized three mAbs that recognize different epitopes on FGFR2: GAL-FR21, GAL-FR22 and GAL-FR23. The ability of the mAbs to recognize the FGFR2IIIb and FGFR2IIIc isoforms of FGFR2 was determined, as was their ability to block binding of FGF ligands to FGFR2. The capability of the mAbs to inhibit FGF-induced FGFR2 phosphorylation and to down-modulate FGFR2 expression was also investigated. Finally, the ability of the anti-FGFR2 mAbs to inhibit tumor growth was determined by establishing xenografts of SNU-16 and OCUM-2M human gastric tumor cell lines in nude mice, treating with each mAb (0.5 – 5 mg/kg i.p. twice weekly), and monitoring tumor size. Results Of the three mAbs, GAL-FR21 binds only the FGFR2IIIb isoform, whereas GAL-FR22 and GAL-FR23 bind to both the FGFR2IIIb and FGFR2IIIc forms, with binding regions respectively in the D3, D2-D3 and D1 domains of FGFR2. GAL-FR21 and GAL-FR22 blocked the binding of FGF2, FGF7 and FGF10 to FGFR2IIIb. GAL-FR21 inhibited FGF2 and FGF7 induced phosphorylation of FGFR2, and both mAbs down-modulated FGFR2 expression on SNU-16 cells. These mAbs effectively inhibited growth of established SNU-16 and OCUM-2M xenografts in mice. Conclusions Anti-FGFR2 mAbs GAL-FR21 and GAL-FR22 have potential for the treatment of gastric and other tumors. PMID:20670946

  7. Fibroblast Growth Factor–23 and Cardiac Structure and Function

    PubMed Central

    Agarwal, Isha; Ide, Noriko; Ix, Joachim H.; Kestenbaum, Bryan; Lanske, Beate; Schiller, Nelson B.; Whooley, Mary A.; Mukamal, Kenneth J.

    2014-01-01

    Background Fibroblast growth factor–23 (FGF?23) is a phosphaturic factor previously associated with left ventricular hypertrophy and systolic dysfunction among individuals with chronic kidney disease. Whether FGF?23 acts directly to induce left ventricular hypertrophy, potentially independent of its klotho coreceptor, remains uncertain. We investigated associations of FGF?23 with cardiac structural abnormalities among individuals with a broad range of kidney function and explored potential biological mechanisms using cardiac magnetic resonance imaging and histology in klotho?null mice, an established model of constitutively elevated FGF?23. Methods and Results Among 887 participants with coronary artery disease in the Heart and Soul Study, FGF?23 was modestly associated with worse left ventricular ejection fraction (?1.0% per standard deviation increase in lnFGF?23; standard error, 0.4%), but was not associated with the overall prevalence of concentric hypertrophy (odds ratio, 1.5; CI, 0.9 to 2.4) or eccentric hypertrophy (odds ratio, 1.1; CI, 0.9 to 1.3). FGF?23 was only associated with concentric hypertrophy among individuals with diminished kidney function (eGFR <60 mL/min per 1.73 m2; odds ratio, 2.3; CI, 1.0 to 5.3; P?interaction=0.28). Comparing klotho?null with wild?type mice, null mice did not have greater left ventricular mass (P=0.37) or a lower ejection fraction (P=0.94). Conclusions Together, our results suggest that FGF?23 is unlikely to have major effects on cardiovascular structure and function among patients free of substantial chronic kidney disease, and these effects may not be independent of the klotho coreceptor. PMID:24525546

  8. Nerve growth factor and its receptor in schizophrenia

    PubMed Central

    Zakharyan, Roksana; Atshemyan, Sofi; Gevorgyan, Anaida; Boyajyan, Anna

    2014-01-01

    Promising studies suggest that defects in synaptic plasticity detected in schizophrenia may be linked to neurodevelopmental and neurodegenerative abnormalities and contribute to disease-associated cognitive impairment. We aimed to clarify the role of the synaptic plasticity regulatory proteins, nerve growth factor (NGF) and its receptor (NGFR) in the pathogenesis of schizophrenia by comparative analysis of their blood levels and functional single nucleotide polymorphisms (SNPs) in genes encoding these proteins (NGF and NGFR) in schizophrenia-affected and healthy subjects. Relationships between the selected SNPs' genotypes and NGF and NGFR plasma levels were also assessed. Our results demonstrated a positive association between schizophrenia and the NGF rs6330 as well as the NGFR rs11466155 and rs2072446 SNPs. Also, a negative association between this disorder and NGF rs4839435 as well as NGFR rs734194 was found. In both, haloperidol-treated and antipsychotic-free patients decreased blood levels of the NGF and NGFR were found, and a positive interrelation between rs6330 and rs2072446 carriage and decreased NGF and NGFR levels, respectively, was revealed. In conclusion, our results demonstrate association of schizophrenia with the rs6330, rs4839435 and rs734194, rs11466155, rs2072446 as well as with the decreased blood levels of corresponding proteins. Our findings indicate the implication of alterations in NGFR and NGFR genes in schizophrenia, particularly, in defects of synaptic plasticity. Furthermore, the data obtained suggests that at least in Armenian population the NGF rs6330*T and NGFR rs11466155*T, rs2072446*T alleles might be nominated as risk factors, whereas the NGF rs4839435*A and NGFR rs734194*G alleles might be protective against developing schizophrenia. PMID:26675984

  9. Controlled multiple growth factor delivery from bone tissue engineering scaffolds via designed affinity.

    PubMed

    Suárez-González, Darilis; Lee, Jae Sung; Diggs, Alisha; Lu, Yan; Nemke, Brett; Markel, Mark; Hollister, Scott J; Murphy, William L

    2014-08-01

    It is known that angiogenesis plays an important role in bone regeneration and that release of angiogenic and osteogenic growth factors can enhance bone formation. Multiple growth factors play key roles in processes that lead to tissue formation/regeneration during natural tissue development and repair. Therefore, treatments aiming to mimic tissue regeneration can benefit from multiple growth factor release, and there remains a need for simple clinically relevant approaches for dual growth factor release. We hypothesized that mineral coatings could be used as a platform for controlled incorporation and release of multiple growth factors. Specifically, mineral-coated scaffolds were "dip coated" in multiple growth factor solutions, and growth factor binding and release were dictated by the growth factor-mineral binding affinity. Beta tricalcium phosphate (?-TCP) scaffolds were fabricated using indirect solid-free form fabrication techniques and coated with a thin conformal mineral layer. Mineral-coated ?-TCP scaffolds were sequentially dipped in recombinant human vascular endothelial growth factor (rhVEGF) and a modular bone morphogenetic peptide, a mineral-binding version of bone morphogenetic protein 2 (BMP2), solutions to allow for the incorporation of each growth factor. The dual release profile showed sustained release of both growth factors for over more than 60 days. Scaffolds releasing either rhVEGF alone or the combination of growth factors showed an increase in blood vessel ingrowth in a dose-dependent manner in a sheep intramuscular implantation model. This approach demonstrates a "modular design" approach, in which a controllable biologics carrier is integrated into a structural scaffold as a thin surface coating. PMID:24350567

  10. Mouse Balb/c3T3 cell mutant with low epidermal growth factor receptor activity: induction of stable anchorage-independent growth by transforming growth factor. beta

    SciTech Connect

    Kuratomi, Y.; Ono, M.; Yasutake, C.; Mawatari, M.; Kuwano, M.

    1987-01-01

    A mutant clone (MO-5) was originally isolated as a clone resistant to Na/sup +//K/sup +/ ionophoric antibiotic monensin from mouse Balb/c3T3 cells. MO-5 was found to show low receptor-endocytosis activity for epidermal growth factor (EGF):binding activity for EGF in MO-5 was less than one tenth of that in Balb/c3T3. Anchorage-independent growth of MO-5 was compared to that of Balb/c3T3 when assayed by colony formation capacity in soft agar. Coadministration of EGF and TGF-..beta.. efficiently enhanced anchorage-independent growth of normal rat kidney (NRK) cells, but neither factor alone was competent to promote the anchorage-independent growth. The frequency of colonies appearing in soft agar of MO-5 or Balb/c3T3 was significantly enhanced by TGF-..beta.. while EGF did not further enhance that of MO-5 or Balb/c3T3. Colonies of Balb/c3T3 formed in soft agar in the presence of TGF-..beta.. showed low colony formation capacity in soft agar in the absence of TGF-..beta... Colonies of MO-5 formed by TGF-..beta.. in soft agar, however, showed high colony formation capacity in soft agar in the absence of TGF-..beta... Pretreatment of MO-5 with TGF-..beta.. induced secretion of TGF-..beta..-like activity from the cells, while the treatment of Balb/c3T3 did not induce the secretion of a significant amount of TGF-..beta..-like activity. The loss of EGF-receptor activity in the stable expression and maintenance of the transformed phenotype in MO-5 is discussed.

  11. Fibroblast Growth Factor-23 in Bed Rest and Spaceflight

    NASA Technical Reports Server (NTRS)

    Bokhari, R.; Zwart, S. R; Fields, E.; Heer, M.; Sibonga, J.; Smith, S. M.

    2014-01-01

    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. Presented with an imbalanced dietary phosphorus to calcium ratio, increased secretion of FGF23 will inhibit renal phosphorus reabsorption, resulting in increased excretion and reduced circulating phosphorus. Increased intake and excretion of phosphorus is associated with increased kidney stone risk in both the terrestrial and microgravity environments. Highly processed foods and carbonated beverages are associated with higher phosphorus content. Ideally, the dietary calcium to phosphorus ratio should be at minimum 1:1. Nutritional requirements for spaceflight suggest that this ratio not be less than 0.67 (3), while the International Space Station (ISS) menu provides 1020 mg Ca and 1856 mg P, for a ratio of 0.55 (3). Subjects in NASA's bed rest studies, by design, have consumed intake ratios much closer to 1.0 (4). FGF23 also has an inhibitory influence on PTH secretion and 1(alpha)-hydroxylase, both of which are required for activating vitamin D with the conversion of 25-hydroxyvitamin D to 1,25-dihydroxyvitamin D. Decreased 1,25-dihydroxyvitamin D will result in decreased intestinal phosphorus absorption, and increased urinary phosphorus excretion (via decreased renal reabsorption). Should a decrease in 1,25- dihydroxyvitamin D be necessary to reduce intestinal phosphorus absorption, calcium absorption will also proportionally be reduced, potentially leading to skeletal demineralization. Demineralization of bone can increase kidney stone risk, a medical issue that could prove detrimental to mission success. Given the interrelationships described above, we sought to determine circulating FGF23 concentrations in spaceflight and ground analog studies to better understand the potential effects of dietary phosphorus on bone and calcium metabolism. We analyzed serum from ISS astronauts participating in studies of bone biochemistry, including the Nutrition SMO and Pro K experiments, and we also evaluated FGF23 during extended-duration bed rest. Serum intact FGF23 levels were determined using an ELISA kit from Kainos laboratories in Japan. While initial evaluation of the data showed no changes over time during flight or bed rest, evaluation continues of FGF23 data in light of dietary factors, PTH, vitamin D status, and other biochemical and endocrine factors.

  12. Expression array analysis of the hepatocyte growth factor invasive program.

    PubMed

    Cecchi, Fabiola; Lih, Chih-Jian; Lee, Young H; Walsh, William; Rabe, Daniel C; Williams, Paul M; Bottaro, Donald P

    2015-10-01

    Signaling by human hepatocyte growth factor (hHGF) via its cell surface receptor (MET) drives mitogenesis, motogenesis and morphogenesis in a wide spectrum of target cell types and embryologic, developmental and homeostatic contexts. Oncogenic pathway activation also contributes to tumorigenesis and cancer progression, including tumor angiogenesis and metastasis, in several prevalent malignancies. The HGF gene encodes full-length hHGF and two truncated isoforms known as NK1 and NK2. NK1 induces all three HGF activities at modestly reduced potency, whereas NK2 stimulates only motogenesis and enhances HGF-driven tumor metastasis in transgenic mice. Prior studies have shown that mouse HGF (mHGF) also binds with high affinity to human MET. Here we show that, like NK2, mHGF stimulates cell motility, invasion and spontaneous metastasis of PC3M human prostate adenocarcinoma cells in mice through human MET. To identify target genes and signaling pathways associated with motogenic and metastatic HGF signaling, i.e., the HGF invasive program, gene expression profiling was performed using PC3M cells treated with hHGF, NK2 or mHGF. Results obtained using Ingenuity Pathway Analysis software showed significant overlap with networks and pathways involved in cell movement and metastasis. Interrogating The Cancer Genome Atlas project also identified a subset of 23 gene expression changes in PC3M with a strong tendency for co-occurrence in prostate cancer patients that were associated with significantly decreased disease-free survival. PMID:26231668

  13. Phthalocyanine-peptide conjugates for epidermal growth factor receptor targeting.

    PubMed

    Ongarora, Benson G; Fontenot, Krystal R; Hu, Xiaoke; Sehgal, Inder; Satyanarayana-Jois, Seetharama D; Vicente, M Graça H

    2012-04-26

    Four phthalocyanine (Pc)-peptide conjugates designed to target the epidermal growth factor receptor (EGFR) were synthesized and evaluated in vitro using four cell lines: human carcinoma A431 and HEp2, human colorectal HT-29, and kidney Vero (negative control) cells. Two peptide ligands for EGFR were investigated: EGFR-L1 and -L2, bearing 6 and 13 amino acid residues, respectively. The peptides and Pc-conjugates were shown to bind to EGFR using both theoretical (Autodock) and experimental (SPR) investigations. The Pc-EGFR-L1 conjugates 5a and 5b efficiently targeted EGFR and were internalized, in part due to their cationic charge, whereas the uncharged Pc-EGFR-L2 conjugates 4b and 6a poorly targeted EGFR maybe due to their low aqueous solubility. All conjugates were nontoxic (IC(50) > 100 ?M) to HT-29 cells, both in the dark and upon light activation (1 J/cm(2)). Intravenous (iv) administration of conjugate 5b into nude mice bearing A431 and HT-29 human tumor xenografts resulted in a near-IR fluorescence signal at ca. 700 nm, 24 h after administration. Our studies show that Pc-EGFR-L1 conjugates are promising near-IR fluorescent contrast agents for CRC and potentially other EGFR overexpressing cancers. PMID:22468711

  14. Fibroblast growth factor-21, energy balance and obesity.

    PubMed

    Giralt, Marta; Gavaldà-Navarro, Aleix; Villarroya, Francesc

    2015-12-15

    Fibroblast growth factor (FGF)-21 is an endocrine member of the FGF family with healthy effects on glucose and lipid metabolism. FGF21 reduces glycemia and lipidemia in rodent models of obesity and type 2 diabetes. In addition to its effects improving insulin sensitivity, FGF21 causes weight loss by increasing energy expenditure. Activation of the thermogenic activity of brown adipose tissue and promotion of the appearance of the so-called beige/brite type of brown adipocytes in white fat are considered the main mechanisms underlying the leaning effects of FGF21. Paradoxically, however, obesity in rodents and humans is characterized by high levels of FGF21 in the blood. Some degree of resistance to the actions of FGF21 has been proposed as part of the endocrine alterations in obesity. The resistance in adipose tissue from obese rodents and patients is likely attributable to abnormally low levels of the FGF co-receptor ?-Klotho, required for FGF21 cellular action. However, native FGF21 and FGF21 derivatives retain their healthy metabolic and weight-loss effects when used as pharmacological agents to treat obese rodents and humans. FGF21 derivatives or molecules mimicking FGF21 action appear to be interesting candidates for the development of novel anti-obesity drugs designed to increase energy expenditure. PMID:26415590

  15. The Neuroprotective Functions of Transforming Growth Factor Beta Proteins

    PubMed Central

    Dobolyi, Arpád; Vincze, Csilla; Pál, Gabriella; Lovas, Gábor

    2012-01-01

    Transforming growth factor beta (TGF-?) proteins are multifunctional cytokines whose neural functions are increasingly recognized. The machinery of TGF-? signaling, including the serine kinase type transmembrane receptors, is present in the central nervous system. However, the 3 mammalian TGF-? subtypes have distinct distributions in the brain suggesting different neural functions. Evidence of their involvement in the development and plasticity of the nervous system as well as their functions in peripheral organs suggested that they also exhibit neuroprotective functions. Indeed, TGF-? expression is induced following a variety of types of brain tissue injury. The neuroprotective function of TGF-?s is most established following brain ischemia. Damage in experimental animal models of global and focal ischemia was shown to be attenuated by TGF-?s. In addition, support for their neuroprotective actions following trauma, sclerosis multiplex, neurodegenerative diseases, infections, and brain tumors is also accumulating. The review will also describe the potential mechanisms of neuroprotection exerted by TGF-?s including anti-inflammatory, -apoptotic, -excitotoxic actions as well as the promotion of scar formation, angiogenesis, and neuroregeneration. The participation of these mechanisms in the neuroprotective effects of TGF-?s during different brain lesions will also be discussed. PMID:22942700

  16. Vascular endothelial growth factor coordinates islet innervation via vascular scaffolding

    PubMed Central

    Reinert, Rachel B.; Cai, Qing; Hong, Ji-Young; Plank, Jennifer L.; Aamodt, Kristie; Prasad, Nripesh; Aramandla, Radhika; Dai, Chunhua; Levy, Shawn E.; Pozzi, Ambra; Labosky, Patricia A.; Wright, Christopher V. E.; Brissova, Marcela; Powers, Alvin C.

    2014-01-01

    Neurovascular alignment is a common anatomical feature of organs, but the mechanisms leading to this arrangement are incompletely understood. Here, we show that vascular endothelial growth factor (VEGF) signaling profoundly affects both vascularization and innervation of the pancreatic islet. In mature islets, nerves are closely associated with capillaries, but the islet vascularization process during embryonic organogenesis significantly precedes islet innervation. Although a simple neuronal meshwork interconnects the developing islet clusters as they begin to form at E14.5, the substantial ingrowth of nerve fibers into islets occurs postnatally, when islet vascularization is already complete. Using genetic mouse models, we demonstrate that VEGF regulates islet innervation indirectly through its effects on intra-islet endothelial cells. Our data indicate that formation of a VEGF-directed, intra-islet vascular plexus is required for development of islet innervation, and that VEGF-induced islet hypervascularization leads to increased nerve fiber ingrowth. Transcriptome analysis of hypervascularized islets revealed an increased expression of extracellular matrix components and axon guidance molecules, with these transcripts being enriched in the islet-derived endothelial cell population. We propose a mechanism for coordinated neurovascular development within pancreatic islets, in which endocrine cell-derived VEGF directs the patterning of intra-islet capillaries during embryogenesis, forming a scaffold for the postnatal ingrowth of essential autonomic nerve fibers. PMID:24574008

  17. Intranasal epidermal growth factor treatment rescues neonatal brain injury

    NASA Astrophysics Data System (ADS)

    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

    2014-02-01

    There are no clinically relevant treatments available that improve function in the growing population of very preterm infants (less than 32 weeks' gestation) with neonatal brain injury. Diffuse white matter injury (DWMI) is a common finding in these children and results in chronic neurodevelopmental impairments. As shown recently, failure in oligodendrocyte progenitor cell maturation contributes to DWMI. We demonstrated previously that the epidermal growth factor receptor (EGFR) has an important role in oligodendrocyte development. Here we examine whether enhanced EGFR signalling stimulates the endogenous response of EGFR-expressing progenitor cells during a critical period after brain injury, and promotes cellular and behavioural recovery in the developing brain. Using an established mouse model of very preterm brain injury, we demonstrate that selective overexpression of human 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 and promotes functional recovery. Furthermore, these interventions diminish ultrastructural abnormalities and alleviate behavioural deficits on white-matter-specific paradigms. Inhibition of EGFR signalling 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 oligodendrocyte progenitor cells at a specific time after injury is clinically feasible and potentially applicable to the treatment of premature children with white matter injury.

  18. Fibroblast growth factor receptor 1 gene amplification in gastric adenocarcinoma.

    PubMed

    Schäfer, Manuel H; Lingohr, Philipp; Sträßer, Anke; Lehnen, Nils C; Braun, Martin; Perner, Sven; Höller, Tobias; Kristiansen, Glen; Kalff, Jörg C; Gütgemann, Ines

    2015-10-01

    Gastric adenocarcinomas are associated with a poor prognosis due to the fact that the tumor has often metastasized by the time of diagnosis. Thus, identification of novel therapeutic targets is highly desirable. Here, we examined gene copy number of fibroblast growth factor receptor 1 (FGFR1), a potential target for tyrosine kinase inhibitors, and clinicopathologic parameters in a large cohort of gastric adenocarcinomas. We performed fluorescence in situ hybridization analysis of 293 gastric adenocarcinomas using tissue microarrays. Amplification of the FGFR1 gene is a rare but noticeable event that can be found in 2% (6/293) of cases and was associated with poor 10-year survival (median 15.3 months in FGFR1-amplified cases versus 36 months in nonamplified cases, P = .047) and a higher rate of distant metastasis (P = .025). FGFR1 appears to represent a potential new therapeutic target in a subset of patients with gastric carcinoma. Identification of gastric cancers harboring FGFR1 amplification may be important in preselecting patients and/or interpreting clinical studies using tyrosine kinase inhibitors. PMID:26239623

  19. [Transforming growth factor-beta as a therapeutic target].

    PubMed

    Gálvez-Gastélum, Francisco Javier; Sandoval-Rodríguez, Ana Soledad; Armendáriz-Borunda, Juan

    2004-01-01

    Transforming growth factor-beta (TGF-beta) family members include TGF-beta, activins, and bone morphogenetic proteins (BMP). These proteins are structurally related cytokines secreted in diverse Metazoans. TGF-beta family members regulate cellular functions such as proliferation, apoptosis, differentiation, and migration, and play an important role in organism development. Deregulated TGF-beta family signaling participates in various human pathologies including autoimmune diseases, vascular disorders, fibrotic disease, and cancer. Ligand-induced activation of TGF-beta family receptors with intrinsic serine/threonine kinase activity, triggers phosphorylation of the intracellular effectors of TGF-beta signaling, the Smads proteins. Once these proteins are activated they translocate into the nucleus, where they induce transcription of target genes and regulate cellular processes and functions. Novel therapeutic strategies are currently being developed to correct alterations in pathologies that involve TGF-beta as the main mediator. The English version of this paper is available at: http://www.insp.mx/salud/index.html. PMID:15468575

  20. Nuclear localization of epidermal growth factor receptor (EGFR) in ameloblastomas

    PubMed Central

    Pereira, Núbia Braga; de Melo do Carmo, Ana Carolina; Diniz, Marina Gonçalves; Gomez, Ricardo Santiago

    2015-01-01

    Background: Ameloblastoma is a locally invasive neoplasm often associated with morbidity and facial deformities, showing increased Epidermal Growth Factor Receptor (EGFR) expression. Inhibition of EGFR was suggested as a treatment option for a subset of ameloblastomas. However, there are resistance mechanisms that impair anti-EGFR therapies. One important resistance mechanism for EGFR-inhibition is the EGFR nuclear localization, which activates genes responsible for its mitogenic effects, such as Cyclin D1. Methods: We assessed EGFR nuclear localization in encapsulated (unicystic, n = 3) and infiltrative (multicystic, n = 11) ameloblastomas and its colocalization with Cyclin D1 by using anti-EGFR and anti-lamin B1 double labeling immunofluorescence analyzed by confocal microscopy. Oral inflammatory fibrous hyperplasia and oral squamous cell carcinoma samples were used for comparison. Results: Twelve cases of ameloblastoma exhibited nuclear EGFR colocalization with lamin B1. This positive staining was mainly observed in the ameloblast-like cells. The EGFR nuclear localization was also observed in control samples. In addition, nuclear EGFR colocalized with Cyclin D1 in ameloblastomas. Conclusions: Nuclear EGFR occurs in ameloblastomas in association with Cyclin D1 expression, which is important in terms of tumor biology clarification and raises a concern about anti-EGFR treatment resistance in ameloblastomas. PMID:25991665

  1. Infiltration of Autologous Growth Factors in Chronic Tendinopathies

    PubMed Central

    Crescibene, Antonio; Napolitano, Marcello; Sbano, Raffaella; Costabile, Enrico; Almolla, Hesham

    2015-01-01

    Achilles tendinopathy and patellar tendinopathy are among the most frequent diagnoses in sports medicine. Therapeutic treatment of the disease is difficult, particularly in chronic cases. In literature, several studies suggest the employment of Platelet-Rich Plasma as a therapeutic alternative in tendinopathies. The choice of employing this method is based on the activity of growth factors contained in platelets which activate, amplify, and optimize the healing process. We selected 14 patients affected by Achilles tendinopathy and 7 patients affected by patellar tendinopathy, with a two-year final follow-up. These patients underwent a cycle of three tendinous infiltrations, after clinical and instrumental evaluation carried out by means of specific questionnaires and repeated ultrasound scans. Ultrasound scans of 18 patients showed signs of reduction in insertional irregularities. The result is confirmed by complete functional recovery of the patients, with painful symptomatology disappearing. The patients showed a clear pain reduction, along with an enhanced VISA score after the 24-month follow-up, equal to 84.2 points on a scale of 0 to 100. In conclusion, the present study provides evidence to suggest that PRP infiltration is a valid option to patients with chronic tendinopathy who did not benefit from other treatments. PMID:26171277

  2. The ontogeny of epidermal growth factor receptors during mouse development

    SciTech Connect

    Adamson, E.D.; Meek, J.

    1984-05-01

    In an attempt to understand the role(s) of epidermal growth factor (EGF) in vivo during murine development, we have examined the /sup 125/I-EGF binding characteristics of EGF-receptors in membrane preparations of tissues from the 12th day of gestation to parturition. Using autoradiography, the earliest time that we could detect EGF-receptors was on trophoblast cells cultured for 3 days as blastocyst outgrowths. Trophoblast eventually forms a large portion of the placenta, where EGF-receptors have long been recognized. We measured the number and affinity of EGF-receptors on tissues dissected from conceptuses from the 12th day of gestation in order to identify a stage when tissues may be most sensitive to EGF. Whereas the number of EGF receptors increases during gestation for all tissues examined, the affinity of the receptors declines for carcass and placenta and remains relatively unchanged for brain and liver. This suggests that EGF may function differently throughout development. Our hypothesis is that EGF (or its embryonic equivalent) initially stimulates proliferation in embryonic cells and then stimulates differentiation as the tissues mature. In the adult, its main role could be to stimulate tissue repair after damage.

  3. Biochemical and biological properties of the nerve growth factor receptor

    SciTech Connect

    Taniuchi, M.

    1988-01-01

    We have utilized a monoclonal antibody (192-IgG) to study the rat nerve growth factor receptor. After intraocular injection, {sup 125}I-192-IgG was retrogradely transported in sympathetic neuronal axons to the superior cervical ganglion. When the sciatic nerve was ligated to induce the accumulation of axonally transported materials, 192-IgG immunostaining was observed on both sides of the ligature, indicating that NGF receptors are transported in both orthograde and retrograde directions. By using {sup 125}I-NGF crosslinking and 192-IgG immunoprecipitation, we detected receptor molecules throughout the rat brain, thereby supporting the hypothesis that NGF is active in the central nervous system. We also discovered that sciatic nerve transection leads to a dramatic increase in the amount of NGF receptor found in the distal portion of the nerve. Immunostaining revealed that all Schwann cells in the distal axotomized nerve were expressing NGF receptors. We examined phosphorylation of NGF receptor in cultured sympathetic neurons and PC12 cells. We also examined pharmacological effects of 192-IgG. Systemic injection of 192-IgG into neonatal rats caused a permanent partial sympathectomy in a dose-dependent manner; a maximum of 50% of the cells were killed.

  4. Molecular pathology of the fibroblast growth factor family

    PubMed Central

    Krejci, Pavel; Prochazkova, Jirina; Bryja, Vitezslav; Kozubik, Alois; Wilcox, William R.

    2009-01-01

    Human fibroblast growth factor (FGF) family contains 22 proteins that regulate a plethora of physiological processes in both developing and adult organism. The mutations in the FGF genes were not known to play role in human disease until the year 2000, when mutations in FGF23 were found to cause hypophosphataemic rickets. Nine years later, seven FGFs have been associated with human disorders. These include FGF3 in Michel aplasia; FGF8 in cleft lip/palate and in hypogonadotropic hypogonadism; FGF9 in carcinoma; FGF10 in the lacrimal/salivary glands aplasia, and lacrimo-auriculo-dento-digital syndrome; FGF14 in spinocerebellar ataxia; FGF20 in Parkinson disease; and FGF23 in tumoral calcinosis and hypophosphataemic rickets. The heterogeneity in the functional consequences of FGF mutations, the modes of inheritance, pattern of involved tissues/organs, and effects in different developmental stages provide fascinating insights into the physiology of the FGF signaling system. This article reviews the current knowledge about the molecular pathology of the FGF family. PMID:19621416

  5. Alterations in fibroblast growth factor receptor expression following brain injury.

    PubMed

    Reilly, J F; Kumari, V G

    1996-08-01

    Traumatic injuries to the central nervous system result in astrogliosis and the formation of a dense scar at the site of the wound. Basic fibroblast growth factor (bFGF) has mitogenic and morphogenic effects on astrocytes, and an interaction between bFGF and its receptor is likely to play a role in astrogliosis. We examined trauma-induced changes in the spatial and temporal expression of FGF receptor (FGFR) in adult rats over a 28-day period following a stereotaxic lesion through the cortex and hippocampus. Immunohistochemistry and image analysis were used to evaluate the changes. Antibody characterization studies strongly suggested that staining represented FGFR 1, but did not rule out possible cross-reactivity with FGFR 2 or 3. Double immunohistochemistry for FGFR and glial fibrillary acidic protein demonstrated that mature astrocytes expressed FGFR. Expression was increased on astrocytes adjacent to the wound cavity by Day 2 postlesion. Staining increased further through Day 10 and decreased to control values by Day 28, except for a sustained increase in staining of reactive astrocytes immediately adjacent to the wound cavity. Basic FGF was detected in the nuclei of cells staining for FGFR, suggesting that FGFR-expressing astrocytes also contained bFGF. These data demonstrate a time course for astrocyte expression of FGFR that precedes and parallels the time course for astrocyte hypertrophy. Our observations suggest that endogenous bFGF, acting directly on FGFR-expressing astrocytes, may contribute to astrogliosis. PMID:8690057

  6. Fibroblast growth factors and their receptors in cancer.

    PubMed

    Wesche, Jørgen; Haglund, Kaisa; Haugsten, Ellen Margrethe

    2011-07-15

    FGFs (fibroblast growth factors) and their receptors (FGFRs) play essential roles in tightly regulating cell proliferation, survival, migration and differentiation during development and adult life. Deregulation of FGFR signalling, on the other hand, has been associated with many developmental syndromes, and with human cancer. In cancer, FGFRs have been found to become overactivated by several mechanisms, including gene amplification, chromosomal translocation and mutations. FGFR alterations are detected in a variety of human cancers, such as breast, bladder, prostate, endometrial and lung cancers, as well as haematological malignancies. Accumulating evidence indicates that FGFs and FGFRs may act in an oncogenic fashion to promote multiple steps of cancer progression by inducing mitogenic and survival signals, as well as promoting epithelial-mesenchymal transition, invasion and tumour angiogenesis. Therapeutic strategies targeting FGFs and FGFRs in human cancer are therefore currently being explored. In the present review we will give an overview of FGF signalling, the main FGFR alterations found in human cancer to date, how they may contribute to specific cancer types and strategies for therapeutic intervention. PMID:21711248

  7. Fibrous Dysplasia and Fibroblast Growth Factor-23 Regulation

    PubMed Central

    Boyce, Alison M; Bhattacharyya, Nisan; Collins, Michael T

    2013-01-01

    Fibrous dysplasia (FD) is a skeletal disorder caused by activating mutations in Gs? that result in elevations in cAMP. A feature of FD is elevated blood levels of the bone cell-derived phosphaturic hormone, fibroblast growth factor-23 (FGF23). FGF23 regulates serum phosphorus and active vitamin D levels by action on proximal renal tubule cells. An essential step in the production of biologically active FGF23 is glycosylation by the UDP-N-acetyl-?-D-galactosamine:polypeptide N-acetylgalactosaminyl transferase (ppGalNAc-T3). In the absence of glycosylation, FGF23 is processed into inactive N- and C-terminal proteins by a subtilisin proprotein convertase, probably furin. Normally, most if not all circulating FGF23 is intact. In FD, C-terminal levels are elevated, suggesting altered FGF23 processing. Altered processing in FD is the result of a cAMP-dependent, coordinated decrease in ppGalNAc-T3 and an increase in furin enzyme activity. These findings, and emerging data from other diseases, suggest regulation of FGF23 processing may be a physiologically important process. PMID:23532406

  8. Nerve growth factor involvement in liver cirrhosis and hepatocellular carcinoma

    PubMed Central

    Rasi, Guido; Serafino, Annalucia; Bellis, Lia; Lonardo, Maria Teresa; Andreola, Federica; Zonfrillo, Manuela; Vennarecci, Giovanni; Pierimarchi, Pasquale; Vallebona, Paola Sinibaldi; Ettorre, Giuseppe Maria; Santoro, Eugenio; Puoti, Claudio

    2007-01-01

    AIM: To define NGF (nerve growth factor) and its high-affinity receptor trkANGF presence and distribution in fibrotic liver and in HCC, and to verify if NGF might have a role in fibrosis and HCC. METHODS: Intracellular distribution of NGF and trkANGF were assessed by immunohistochemistry and immuno-electron microscopy in liver specimens from HCC, cirrhosis or both. ELISA was used to measure circulating NGF levels. RESULTS: NGF and trkANGF were highly expressed in HCC tissue, mainly localized in hepatocytes, endothelial and some Kupffer cells. In the cirrhotic part of the liver they were also markedly expressed in bile ducts epithelial and spindle-shaped cells. Surprisingly, in cirrhotic tissue from patients without HCC, both NGF and trkANGF were negative. NGF serum levels in cirrhotic and/or HCC patient were up to 25-fold higher than in controls. CONCLUSION: NGF was only detected in liver tissue with HCC present. Intracellular distribution suggests paracrine and autocrine mechanisms of action. Better definition of mechanisms may allow for therapeutic and diagnostic/prognostic use of NGF. PMID:17854142

  9. Factors controlling ebro deep-sea fan growth, Mediterranean Sea

    SciTech Connect

    Nelson, C.H.; Maldonado, A.; Alonso, B.; Palanques, A.; Ryan, W.B.F.; Kastens, K.; O'Connel, S.

    1985-01-01

    Tectonic, sediment-source and sea-level factors control depositional patterns of the Ebro deep-sea fan system. In unstable, steep continental slope terrain, mass movement of material results in wide gullied canyons and formation of non-channelized debris aprons. These fan channels develop low sinuosity and generally traverse the continental rise without feeding into depositional lobes because of steep gradients (1:50 to 1:100) and sediment draining into the subsiding Valencia Valley graben. An abundance of sediment input points from mass failure and many river-fed canyons contributes to a depositional pattern of side-by-side debris aprons and separate channel-levee complexes. When a large sediment supply feeds a channel for a relatively long period 1) fan valley sinuosity increases: 2) channel walls are modified through undercutting, slumping, and crevasse splays: 3) channel bifurcation occurs: 4) incipient depositional lobe formation begins. Lowering of sea levels in Late Pleistocene time permitted the access of coarse river sediment to slope valleys and promoted deposition of numerous turbidites and active growth of the fan. During the Holocene, when sea levels have been high, a regime of hemipelagic sedimentation, mass movement, and debris apron sedimentation has dominated.

  10. Functional Diversity of Fibroblast Growth Factors in Bone Formation

    PubMed Central

    Minamizaki, Tomoko; Yoshiko, Yuji

    2015-01-01

    The functional significance of fibroblast growth factor (FGF) signaling in bone formation has been demonstrated through genetic loss-of-function and gain-of-function approaches. FGFs, comprising 22 family members, are classified into three subfamilies: canonical, hormone-like, and intracellular. The former two subfamilies activate their signaling pathways through FGF receptors (FGFRs). Currently, intracellular FGFs appear to be primarily involved in the nervous system. Canonical FGFs such as FGF2 play significant roles in bone formation, and precise spatiotemporal control of FGFs and FGFRs at the transcriptional and posttranscriptional levels may allow for the functional diversity of FGFs during bone formation. Recently, several research groups, including ours, have shown that FGF23, a member of the hormone-like FGF subfamily, is primarily expressed in osteocytes/osteoblasts. This polypeptide decreases serum phosphate levels by inhibiting renal phosphate reabsorption and vitamin D3 activation, resulting in mineralization defects in the bone. Thus, FGFs are involved in the positive and negative regulation of bone formation. In this review, we focus on the reciprocal roles of FGFs in bone formation in relation to their local versus systemic effects. PMID:25873956

  11. Transforming growth factor beta (TGF-?) and inflammation in cancer

    PubMed Central

    Bierie, Brian; Moses, Harold L.

    2009-01-01

    The transforming growth factor beta (TGF-?) has been studied with regard to the regulation of cell behavior for over three decades. A large body of research has been devoted to the regulation of epithelial cell and derivative carcinoma cell populations in vitro and in vivo. TGF-? has been shown to inhibit epithelial cell cycle progression and promote apoptosis that together significantly contribute to the tumor suppressive role for TGF-? during carcinoma initiation and progression. However, TGF-? is also able to promote an epithelial to mesenchymal transition that has been associated with increased tumor cell motility, invasion and metastasis. However, it has now been shown that loss of carcinoma cell responsiveness to TGF-? stimulation can also promote metastasis. Interestingly, the enhanced metastasis in the absence of a carcinoma cell response to TGF-? stimulation has been shown to involve increased chemokine production resulting in recruitment of pro-metastatic myeloid derived suppressor cell (MDSC) populations to the tumor microenvironment at the leading invasive edge. When present, MDSCs enhance angiogenesis, promote immune tolerance and provide matrix degrading enzymes that promote tumor progression and metastasis. Further, the recruitment of MDSC populations in this context likely enhances the classic role for TGF-? in immune suppression since the MDSCs are an abundant source of TGF-? production. Importantly, it is now clear that carcinoma-immune cell cross-talk initiated by TGF-? signaling within the carcinoma cell is a significant determinant worth consideration when designing therapeutic strategies to manage tumor progression and metastasis. PMID:20018551

  12. Distribution and release of epidermal growth factor in man.

    PubMed Central

    Konturek, J W; Bielanski, W; Konturek, S J; Bogdal, J; Oleksy, J

    1989-01-01

    Epidermal growth factor (EGF) is localised in man to salivary and Brunner's glands. It is present in large concentrations in saliva and duodenal contents but the mechanisms of its release have been little studied. This study carried out on four groups of healthy subjects was designed to determine the distribution and the release of immunoreactive EGF (IR-EGF) in salivary, gastric, duodenal, and pancreatic secretions. Under basal conditions, the concentrations of IR-EGF in salivary, gastric, duodenal and pancreatic secretions were; 2.7 (0.4), 0.42 (0.12), 21 (5) and 8.5 (1.2) ng/ml, respectively. Chewing of Parafilm* significantly increased salivary but not gastric or duodenal EGF output while atropinisation led to the reduction in basal salivary and duodenal EGF output without affecting the increment in EGF release induced by chewing. Cigarette smoking caused a marked reduction in basal salivary and duodenal EGF output. Infusion of pentagastrin increased salivary and duodenal EGF output and this was blocked by the addition of somatostatin. Injection of secretin lead to an increase in pancreatic output of EGF. We conclude that in man the major sources of EGF are salivary glands, duodenum, and pancreas and that the release of EGF remains under neurohormonal control. PMID:2806986

  13. Growth hormone and insulin-like growth factors in fish: Where we are and where to go

    USGS Publications Warehouse

    Reinecke, M.; Bjornsson, Bjorn Thrandur; Dickhoff, Walton W.; McCormick, S.D.; Navarro, I.; Power, D.M.; Gutierrez, J.

    2005-01-01

    This communication summarizes viewpoints, discussion, perspectives, and questions, put forward at a workshop on "Growth hormone and insulin-like growth factors in fish" held on September 7th, 2004, at the 5th International Symposium on Fish Endocrinology in Castello??n, Spain. ?? 2005 Elsevier Inc. All rights reserved.

  14. Chitosan conduits combined with nerve growth factor microspheres repair facial nerve defects

    PubMed Central

    Liu, Huawei; Wen, Weisheng; Hu, Min; Bi, Wenting; Chen, Lijie; Liu, Sanxia; Chen, Peng; Tan, Xinying

    2013-01-01

    Microspheres containing nerve growth factor for sustained release were prepared by a compound method, and implanted into chitosan conduits to repair 10-mm defects on the right buccal branches of the facial nerve in rabbits. In addition, chitosan conduits combined with nerve growth factor or normal saline, as well as autologous nerve, were used as controls. At 90 days post-surgery, the muscular atrophy on the right upper lip was more evident in the nerve growth factor and normal sa-line groups than in the nerve growth factor-microspheres and autologous nerve groups. physiological analysis revealed that the nerve conduction velocity and amplitude were significantly higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. Moreover, histological observation illustrated that the di-ameter, number, alignment and myelin sheath thickness of myelinated nerves derived from rabbits were higher in the nerve growth factor-microspheres and autologous nerve groups than in the nerve growth factor and normal saline groups. These findings indicate that chitosan nerve conduits bined with microspheres for sustained release of nerve growth factor can significantly improve facial nerve defect repair in rabbits. PMID:25206635

  15. Structural and Functional Properties of Platelet-Derived Growth Factor and Stem Cell Factor Receptors

    PubMed Central

    Heldin, Carl-Henrik; Lennartsson, Johan

    2013-01-01

    The receptors for platelet-derived growth factor (PDGF) and stem cell factor (SCF) are members of the type III class of PTK receptors, which are characterized by five Ig-like domains extracellularly and a split kinase domain intracellularly. The receptors are activated by ligand-induced dimerization, leading to autophosphorylation on specific tyrosine residues. Thereby the kinase activities of the receptors are activated and docking sites for downstream SH2 domain signal transduction molecules are created; activation of these pathways promotes cell growth, survival, and migration. These receptors mediate important signals during the embryonal development, and control tissue homeostasis in the adult. Their overactivity is seen in malignancies and other diseases involving excessive cell proliferation, such as atherosclerosis and fibrotic diseases. In cancer, mutations of PDGF and SCF receptors—including gene fusions, point mutations, and amplifications—drive subpopulations of certain malignancies, such as gastrointestinal stromal tumors, chronic myelomonocytic leukemia, hypereosinophilic syndrome, glioblastoma, acute myeloid leukemia, mastocytosis, and melanoma. PMID:23906712

  16. Luteolin Inhibits Human Prostate Tumor Growth by Suppressing Vascular Endothelial Growth Factor Receptor 2-Mediated Angiogenesis

    PubMed Central

    Pratheeshkumar, Poyil; Son, Young-Ok; Budhraja, Amit; Wang, Xin; Ding, Songze; Wang, Lei; Hitron, Andrew; Lee, Jeong-Chae; Kim, Donghern; Divya, Sasidharan Padmaja; Chen, Gang; Zhang, Zhuo; Luo, Jia; Shi, Xianglin

    2012-01-01

    Angiogenesis, the formation of new blood vessels from pre-existing vascular beds, is essential for tumor growth, invasion, and metastasis. Luteolin is a common dietary flavonoid found in fruits and vegetables. We studied the antiangiogenic activity of luteolin using in vitro, ex vivo, and in vivo models. In vitro studies using rat aortic ring assay showed that luteolin at non-toxic concentrations significantly inhibited microvessel sprouting and proliferation, migration, invasion and tube formation of endothelial cells, which are key events in the process of angiogenesis. Luteolin also inhibited ex vivo angiogenesis as revealed by chicken egg chorioallantoic membrane assay (CAM) and matrigel plug assay. Gelatin zymographic analysis demonstrated the inhibitory effect of luteolin on the activation of matrix metalloproteinases MMP-2 and MMP-9. Western blot analysis showed that luteolin suppressed VEGF induced phosphorylation of VEGF receptor 2 and their downstream protein kinases AKT, ERK, mTOR, P70S6K, MMP-2, and MMP-9 in HUVECs. Proinflammatory cytokines such as IL-1?, IL-6, IL-8, and TNF-? level were significantly reduced by the treatment of luteolin in PC-3 cells. Luteolin (10 mg/kg/d) significantly reduced the volume and the weight of solid tumors in prostate xenograft mouse model, indicating that luteolin inhibited tumorigenesis by targeting angiogenesis. CD31 and CD34 immunohistochemical staining further revealed that the microvessel density could be remarkably suppressed by luteolin. Moreover, luteolin reduced cell viability and induced apoptosis in prostate cancer cells, which were correlated with the downregulation of AKT, ERK, mTOR, P70S6K, MMP-2, and MMP-9 expressions. Taken together, our findings demonstrate that luteolin inhibits human prostate tumor growth by suppressing vascular endothelial growth factor receptor 2-mediated angiogenesis. PMID:23300633

  17. Level of macroautophagy drives senescent keratinocytes into cell death or neoplastic evasion

    PubMed Central

    Deruy, E; Nassour, J; Martin, N; Vercamer, C; Malaquin, N; Bertout, J; Chelli, F; Pourtier, A; Pluquet, O; Abbadie, C

    2014-01-01

    Senescence is a non-proliferative state reached by normal cells in response to various stresses, including telomere uncapping, oxidative stress or oncogene activation. In previous reports, we have highlighted that senescent human epidermal keratinocytes have two opposite outcomes: either they die by autophagic programmed cell death or they evade in the form of neoplastic postsenescence emergent (PSNE) cells. Herein, we show that partially reducing macroautophagy in senescent keratinocytes using 3-methyl adenine or anti-Atg5 siRNAs increases the PSNE frequency, suggesting that senescent keratinocytes have to escape autophagic cell death to generate PSNE cells. However, totally inhibiting macroautophagy impairs PSNE and leads to a huge accumulation of oxidative damages, indicating that senescent keratinocytes need to achieve quality-control macroautophagy for PSNE to occur. In accordance, we demonstrate that the progenitors of PSNE cells display a level of macroautophagy slightly lower than that of the average senescent population, which is directly dictated by their level of reactive oxygen species, their level of upregulation of MnSOD, their level of activation of NF-?B transcription factors and their level of dysfunctional mitochondria. Macroautophagy thus has antagonistic roles during senescence, inducing cell death or promoting neoplastic transformation, depending on its level of activation. Taken together, these data suggest that levels of oxidative damages and ensuing macroautophagic activity could be two main determinants of the very initial phases of neoplastic transformation by senescence evasion. PMID:25522271

  18. A novel Nrf2-miR-29-desmocollin-2 axis regulates desmosome function in keratinocytes.

    PubMed

    Kurinna, Svitlana; Schäfer, Matthias; Ostano, Paola; Karouzakis, Emmanuel; Chiorino, Giovanna; Bloch, Wilhelm; Bachmann, Andreas; Gay, Steffen; Garrod, David; Lefort, Karine; Dotto, Gian-Paolo; Beer, Hans-Dietmar; Werner, Sabine

    2014-01-01

    The Nrf2 transcription factor controls the expression of genes involved in the antioxidant defense system. Here, we identified Nrf2 as a novel regulator of desmosomes in the epidermis through the regulation of microRNAs. On Nrf2 activation, expression of miR-29a and miR-29b increases in cultured human keratinocytes and in mouse epidermis. Chromatin immunoprecipitation identified the Mir29ab1 and Mir29b2c genes as direct Nrf2 targets in keratinocytes. While binding of Nrf2 to the Mir29ab1 gene activates expression of miR-29a and -b, the Mir29b2c gene is silenced by DNA methylation. We identified desmocollin-2 (Dsc2) as a major target of Nrf2-induced miR-29s. This is functionally important, since Nrf2 activation in keratinocytes of transgenic mice causes structural alterations of epidermal desmosomes. Furthermore, the overexpression of miR-29a/b or knockdown of Dsc2 impairs the formation of hyper-adhesive desmosomes in keratinocytes, whereas Dsc2 overexpression has the opposite effect. These results demonstrate that a novel Nrf2-miR-29-Dsc2 axis controls desmosome function and cutaneous homeostasis. PMID:25283360

  19. 12-hydroxyheptadecatrienoic acid promotes epidermal wound healing by accelerating keratinocyte migration via the BLT2 receptor

    PubMed Central

    Liu, Min; Matsunobu, Takehiko; Okuno, Toshiaki; Koga, Tomoaki; Sugimoto, Yukihiko; Yokoyama, Chieko; Nakamizo, Satoshi; Kabashima, Kenji; Narumiya, Shuh; Shimizu, Takao

    2014-01-01

    Leukotriene B4 (LTB4) receptor type 2 (BLT2) is a G protein–coupled receptor (GPCR) for 12(S)-hydroxyheptadeca-5Z,8E,10E-trienoic acid (12-HHT) and LTB4. Despite the well-defined proinflammatory roles of BLT1, the in vivo functions of BLT2 remain elusive. As mouse BLT2 is highly expressed in epidermal keratinocytes, we investigated the role of the 12-HHT/BLT2 axis in skin wound healing processes. 12-HHT accumulated in the wound fluid in mice, and BLT2-deficient mice exhibited impaired re-epithelialization and delayed wound closure after skin punching. Aspirin administration reduced 12-HHT production and resulted in delayed wound closure in wild-type mice, which was abrogated in BLT2-deficient mice. In vitro scratch assay using primary keratinocytes and a keratinocyte cell line also showed that the 12-HHT/BLT2 axis accelerated wound closure through the production of tumor necrosis factor ? (TNF) and matrix metalloproteinases (MMPs). A synthetic BLT2 agonist accelerated wound closure in cultured cells as well as in C57BL/6J and diabetic mice. These results identify a novel mechanism underlying the action of the 12-HHT/BLT2 axis in epidermal keratinocytes and accordingly suggest the use of BLT2 agonists as therapeutic agents to accelerate wound healing, particularly for intractable wounds, such as diabetic ulcers. PMID:24821912

  20. Rat Prolactinoma cell growth regulation by Epidermal Growth Factor receptor ligands

    PubMed Central

    Vlotides, George; Siegel, Emily; Donangelo, Ines; Gutman, Shiri; Ren, Song-Guang; Melmed, Shlomo

    2008-01-01

    Epidermal growth factor (EGF) regulates pituitary development, hormone synthesis and cell proliferation. Although ErbB receptor family members are expressed in pituitary tumors, effects of EGF signaling on pituitary tumors are not known. Immunoprecipitation and Western blot confirmed EGFR and p185c-neu protein expression in GH3 lacto-somatotroph but not in ACTH-secreting AtT20 pituitary tumor cells. EGF (5 nM) selectively enhanced baseline (~ 4-fold) and serum-induced (> 6-fold) PRL mRNA levels, while gefitinib, an EGFR antagonist, suppressed serum-induced cell proliferation and Pttg1 expression, blocked PRL gene expression, and reversed EGF-mediated somatotroph-lactotroph phenotype switching. Downstream EGFR signaling by ERK, but not PI3K or PKC, mediated the gefitinib-response. Tumors in athymic mice implanted sc with GH3 cells resulted in weight gain accompanied by increased serum PRL, GH and IGF-I levels. Gefitinib decreased tumor volumes and peripheral hormone levels by ~ 30% and restored normal mouse body weight patterns. Mice treated with gefitinib exhibited decreased tumor tissue ERK1/2 phosphorylation and downregulated tumor PRL and Pttg1 mRNA abundance. These results show that EGFR inhibition controls tumor growth and PRL secretion in experimental lacto-somatotroph tumors. EGFR inhibitors could therefore be useful for control of PRL secretion and tumor load in prolactinomas resistant to dopaminergic treatment, or for those prolactinomas undergoing rare malignant transformation. PMID:18676863

  1. Oridonin protects HaCaT keratinocytes against hydrogen peroxide-induced oxidative stress by altering microRNA expression.

    PubMed

    Bae, Seunghee; Lee, Eun-Jin; Lee, Jae Ho; Park, In-Chul; Lee, Su-Jae; Hahn, Hyung Jin; Ahn, Kyu Joong; An, Sungkwan; An, In-Sook; Cha, Hwa Jun

    2014-01-01

    microRNAs (miRNAs) have been shown to function as primary regulators of a variety of biological processes, including proliferation, differentiation and apoptosis in human keratinocytes. However, the biological significance of miRNAs in the defense against oxidative stress in keratinocytes remains to be elucidated. In this study, we demonstrate that oridonin, a diterpenoid compound isolated from Rabdosia rubescens with established antioxidant properties, protects HaCaT human keratinocytes from oxidative stress induced by exposure to hydrogen peroxide (H2O2). Our data demonstrate that low doses of oridonin (1-5 µM) protect keratinocytes against H2O2-induced apoptosis in a concentration- and time-dependent manner. Moreover, as shown by our results, oridonin markedly decreased H2O2-induced reactive oxygen species production in HaCaT cells. Oridonin mediated these effects by altering miRNA expression. Bioinformatics analysis identified several putative target genes of the differentially expressed miRNAs. Assessment of their gene ontology annotation revealed that these target genes are likely involved in cell growth and inhibition of apoptosis. Thus, the data from this study establish a role for miRNAs in mediating oridonin-induced protective effects against oxidative stress in human keratinocytes. PMID:24253257

  2. Involvement of interleukin-8, vascular endothelial growth factor, and basic fibroblast growth factor in tumor necrosis factor alpha-dependent angiogenesis.

    PubMed Central

    Yoshida, S; Ono, M; Shono, T; Izumi, H; Ishibashi, T; Suzuki, H; Kuwano, M

    1997-01-01

    Tumor necrosis factor alpha (TNF-alpha) is a macrophage/monocyte-derived polypeptide which modulates the expression of various genes in vascular endothelial cells and induces angiogenesis. However, the underlying mechanism by which TNF-alpha mediates angiogenesis is not completely understood. In this study, we assessed whether TNF-alpha-induced angiogenesis is mediated through TNF-alpha itself or indirectly through other TNF-alpha-induced angiogenesis-promoting factors. Cellular mRNA levels of interleukin-8 (IL-8), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and their receptors were increased after the treatment of human microvascular endothelial cells with TNF-alpha (100 U/ml). TNF-alpha-dependent tubular morphogenesis in vascular endothelial cells was inhibited by the administration of anti-IL-8, anti-VEGF, and anti-bFGF antibodies, and coadministration of all three antibodies almost completely abrogated tubular formation. Moreover, treatment with Sp1, NF-kappaB, and c-Jun antisense oligonucleotides inhibited TNF-alpha-dependent tubular morphogenesis by microvascular endothelial cells. Administration of a NF-kappaB antisense oligonucleotide almost completely inhibited TNF-alpha-dependent IL-8 production and partially abrogated TNF-alpha-dependent VEGF production, and an Sp1 antisense sequence partially inhibited TNF-alpha-dependent production of VEGF. A c-Jun antisense oligonucleotide significantly inhibited TNF-alpha-dependent bFGF production but did not affect the production of IL-8 and VEGF. Administration of an anti-IL-8 or anti-VEGF antibody also blocked TNF-alpha-induced neovascularization in the rabbit cornea in vivo. Thus, angiogenesis by TNF-alpha appears to be modulated through various angiogenic factors, both in vitro and in vivo, and this pathway is controlled through paracrine and/or autocrine mechanisms. PMID:9199336

  3. Effect of intestinal ischemia-reperfusion on expressions of endogenous basic fibroblast growth factor and transforming growth factor ? in lung and its relation with lung repair

    PubMed Central

    Fu, Xiao-Bing; Yang, Yin-Hui; Sun, Tong-Zhu; Gu, Xiao-Man; Jiang, Li-Xian; Sun, Xiao-Qing; Sheng, Zhi-Yong

    2000-01-01

    AIM: To study the changes of endogenous transforming growth factor ? (TGF-?) and basic fibroblast growth factor (bFGF) in lung following intestinal ischemia and reperfusion injury and their effects on lung injury and repair. METHODS: Sixty Wistar rats were divided into five groups, which underwent sham-operation, ischemia (45 min), and reperfusion (6, 24 and 48 h, respectively) after ischemia (45 min). Immunohistochemical method was used to observe the localization and amounts of both growth factors. RESULTS: Positive signals of both growth factors could be found in normal lung, mainly in alveolar cells and endothelial cells of vein. After ischemia and reperfusion insult, expressions of both growth factors were increased and their amounts at 6 h were larger than those of normal control or of 24 and 48 h after insult. CONCLUSION: The endogenous bFGF and TGF-?expression appears to be up-regulated in the lung following intestinal ischemia and reperfusion, suggesting that both growth factors may be involved in the process of lung injury and repair. PMID:11819596

  4. Regulation of Heparin-Binding EGF-Like Growth Factor by miR-212 and Acquired Cetuximab-Resistance in Head and Neck Squamous Cell Carcinoma

    PubMed Central

    Hatakeyama, Hiromitsu; Cheng, Haixia; Wirth, Pamela; Counsell, Ashley; Marcrom, Samuel R.; Wood, Carey Burton; Pohlmann, Paula R.; Gilbert, Jill; Murphy, Barbara; Yarbrough, Wendell G.; Wheeler, Deric L.; Harari, Paul M.; Guo, Yan; Shyr, Yu; Slebos, Robbert J.; Chung, Christine H.

    2010-01-01

    Background We hypothesized that chronic inhibition of epidermal growth factor receptor (EGFR) by cetuximab, a monoclonal anti-EGFR antibody, induces up-regulation of its ligands resulting in resistance and that microRNAs (miRs) play an important role in the ligand regulation in head and neck squamous cell carcinoma (HNSCC). Methodology/Principal Findings Genome-wide changes in gene and miR expression were determined in cetuximab-sensitive cell line, SCC1, and its resistant derivative 1Cc8 using DNA microarrays and RT-PCR. The effects of differentially expressed EGFR ligands and miRs were examined by MTS, colony formation, ELISA, and western blot assays. Heparin-binding EGF-like growth factor (HB-EGF) and its regulator, miR-212, were differentially expressed with statistical significance when SCC1 and 1Cc8 were compared for gene and miR expression. Stimulation with HB-EGF induced cetuximab resistance in sensitive cell lines. Inhibition of HB-EGF and the addition of miR-212 mimic induced cetuximab sensitivity in resistant cell lines. MicroRNA-212 and HB-EGF expression were inversely correlated in an additional 33 HNSCC and keratinocyte cell lines. Six tumors and 46 plasma samples from HNSCC patients were examined for HB-EGF levels. HB-EGF plasma levels were lower in newly diagnosed HNSCC patients when compared to patients with recurrent disease. Conclusions/Significance Increased expression of HB-EGF due to down-regulation of miR-212 is a possible mechanism of cetuximab resistance. The combination of EGFR ligand inhibitors or miR modulators with cetuximab may improve the clinical outcome of cetuximab therapy in HNSCC. PMID:20856931

  5. Tumor induced osteomalacia: associated with elevated circulating levels of fibroblast growth factor-7 in addition to fibroblast growth factor-23.

    PubMed

    Bansal, Shweta; Khazim, Khaled; Suri, Rajeev; Martin, DeAndra; Werner, Sherry; Fanti, Paolo

    2016-01-01

    Tumor induced osteomalacia (TIO) is a rare paraneoplastic syndrome characterized by renal phosphate wasting, hypophosphatemia, and osteomalacia. Fibroblast growth factor (FGF)-23, a phosphatonin i.e., phosphaturia-promoting hormone, is commonly implicated in the pathogenesis of TIO. However, very limited information is available about the circulating levels and clinical significance of other phosphatonins that are expressed by TIO-associated tumors. In addition, identification of the primary tumor constitutes a frequent major challenge in the management of TIO. Here, we report a patient with the clinical diagnosis of TIO with elevated blood levels of the phosphatonins FGF-23 and FGF-7; and extensive but unrewarding radiological search for the primary tumor. In selective venous sampling, both FGF-23 and FGF-7 displayed highest concentrations in the left femoral and iliac veins; although lateralization was much more pronounced for FGF-7 than FGF-23. This laboratory finding allowed us to focus on the left lower extremity as the likely location of the primary tumor. Our case is the first to show that FGF-7 can be analyzed in the circulation and used to assist in the diagnosis and localization of TIO-associated tumors. PMID:26521888

  6. Characterisation of angiogenetic growth factor production in adipose tissue-derived mesenchymal cells.

    PubMed

    Pallua, Norbert; Serin, Merdan; Wolter, Timm P

    2014-12-01

    Optimal vascularisation of the graft site is significant for improving the outcome of fat grafting. Adipose tissue, specifically the stromal vascular fraction (SVF), is known to regulate its own vascular network. In order to assess the production of angiogenetic growth factors, this study investigated the content of insulin growth factor (IGF), vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), platelet-derived growth factor (PDGF), leptin, and metallothioneine-9 (MMP-9) in the SVF after incubation in differentiation or proliferation media. The SVF was isolated from human subcutaneous adipose tissue. Cells were either cultured in proliferation medium (PM) or in differentiation medium (DM). The samples were analysed for the respective factors using ELISA after 3 and 6 days. The GF levels showed a distinctive characteristic over time depending on the culture medium. IGF, PDGF, and MMP-9 levels decreased with PM and increased with DM. VEGF levels were increased in both media. Leptin showed a decrease in both media. The differentiation medium was associated with high inter-individual distribution in growth factor production except for PDGF and Leptin. In conclusion, incubation with differentiation medium produces a more reliable increase of selected growth factors than incubation with proliferation medium. Enrichment of fat grafts with growth factor-activated autologous SVF samples could help to enable better ingrowth of the transplanted tissue and a more stable outcome. The scattering of the results could explain the inter-individual differences regarding the outcome. PMID:24697610