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Sample records for factor receptor tnfr

  1. Protective role of tumor necrosis factor (TNF) receptors in chronic intestinal inflammation: TNFR1 ablation boosts systemic inflammatory response.

    Science.gov (United States)

    Wang, Yi; Han, Gencheng; Chen, Yu; Wang, Ke; Liu, Guijun; Wang, Renxi; Xiao, He; Li, Xinying; Hou, Chunmei; Shen, Beifen; Guo, Renfeng; Li, Yan; Chen, Guojiang

    2013-09-01

    Tumor necrosis factor-α (TNF-α) acts as a key factor for the development of inflammatory bowel diseases (IBDs), whose function is known to be mediated by TNF receptor 1 (TNFR1) or TNFR2. However, the precise role of the two receptors in IBD remains poorly understood. Herein, chronic colitis was established by oral administration of dextran sulfate sodium (DSS) in TNFR1 or TNFR2-/- mice. Unexpectedly, TNFR1 or TNFR2 deficiency led to exacerbation of signs of colitis compared with wild-type (WT) counterparts. Of note, TNFR1 ablation rendered significantly increased mortality compared with TNFR2 and WT mice after DSS. Aggravated pathology of colitis in TNFR1-/- or TNFR2-/- mice correlated with elevated colonic expression of proinflammatory cytokines and chemokines. Importantly, ablation of TNFR1 or TNFR2 increased apoptosis of colonic epithelial cells, which might be due to the heightened ratio of Bax/Bcl-2 and increased expression of caspase-8. Intriguingly, despite comparable intensity of intestinal inflammation in TNFR-deficient mice after DSS, systemic inflammatory response (including splenomegaly and myeloid expansion) was augmented dramatically in TNFR1-/- mice, instead of TNFR2-/- mice. Granulocyte-macrophage colony-stimulating factor (GMCSF) was identified as a key mediator in this process, as neutralization of GMCSF dampened peripheral inflammatory reaction and reduced mortality in TNFR1-/- mice. These data suggest that signaling via TNFR1 or TNFR2 has a protective role in chronic intestinal inflammation, and that lacking TNFR1 augments systemic inflammatory response in GMCSF-dependent manner.

  2. Poxvirus tumor necrosis factor receptor (TNFR)-like T2 proteins contain a conserved preligand assembly domain that inhibits cellular TNFR1-induced cell death.

    Science.gov (United States)

    Sedger, Lisa M; Osvath, Sarah R; Xu, Xiao-Ming; Li, Grace; Chan, Francis K-M; Barrett, John W; McFadden, Grant

    2006-09-01

    The poxvirus tumor necrosis factor receptor (TNFR) homologue T2 has immunomodulatory properties; secreted myxoma virus T2 (M-T2) protein binds and inhibits rabbit TNF-alpha, while intracellular M-T2 blocks virus-induced lymphocyte apoptosis. Here, we define the antiapoptotic function as inhibition of TNFR-mediated death via a highly conserved viral preligand assembly domain (vPLAD). Jurkat cell lines constitutively expressing M-T2 were generated and shown to be resistant to UV irradiation-, etoposide-, and cycloheximide-induced death. These cells were also resistant to human TNF-alpha, but M-T2 expression did not alter surface expression levels of TNFRs. Previous studies indicated that T2's antiapoptotic function was conferred by the N-terminal region of the protein, and further examination of this region revealed a highly conserved N-terminal vPLAD, which is present in all poxvirus T2-like molecules. In cellular TNFRs and TNF-alpha-related apoptosis-inducing ligand (TRAIL) receptors (TRAILRs), PLAD controls receptor signaling competency prior to ligand binding. Here, we show that M-T2 potently inhibits TNFR1-induced death in a manner requiring the M-T2 vPLAD. Furthermore, we demonstrate that M-T2 physically associates with and colocalizes with human TNFRs but does not prevent human TNF-alpha binding to cellular receptors. Thus, M-T2 vPLAD is a species-nonspecific dominant-negative inhibitor of cellular TNFR1 function. Given that the PLAD is conserved in all known poxvirus T2-like molecules, we predict that it plays an important function in each of these proteins. Moreover, that the vPLAD confers an important antiapoptotic function confirms this domain as a potential target in the development of the next generation of TNF-alpha/TNFR therapeutics.

  3. Colitogenic role of tumour necrosis factor (TNF) receptors in trinitrobenzene sulphonic acid colitis: TNF-R1 ablation does not affect systemic inflammatory response.

    Science.gov (United States)

    Yang, Y; Wang, H; Dou, Y; Wang, Y; Han, G; Wang, Renxi; Wang, L; Guo, R; Xiao, H; Li, X; Shen, B; Shi, Y; Chen, G; Li, Y

    2011-09-01

    Tumour necrosis factor (TNF)-α plays a critical role in the pathogenesis of T helper type 1-mediated colitis such as Crohn's disease. However, the roles of its two receptors in mediating pathology remain largely unknown. In this study, trinitrobenzene sulphonic acid (TNBS) was used to induce colitis in TNF-receptor single or double knock-out (DKO) BALB/c mice and in wild-type counterparts. TNF-R1(-/-) mice had significantly less weight loss, reduced mortality, colon shortening and oedema, colon histological damage and lower levels of colon myeloperoxidase compared with wild-type (WT) BALB/c mice. A similar manifestation was also observed in TNF-R2(-/-) and TNF-R1(-/-) TNF-R2(-/-) (TNF-R DKO) mice. Strikingly, systemic inflammatory response (including splenomegaly and monocyte expansion) was found in WT and TNF-R1(-/-) mice after TNBS, instead of TNF-R2(-/-) and TNF-R DKO mice. Attenuated pathology of colitis in TNF-R1(-/-) or TNF-R2(-/-) mice correlated with lower amounts of interleukin (IL)-6, IL-1β, monocyte chemotactic protein (MCP)-1, IL-12p70 and interferon (IFN)-γ production in the colons. Importantly, ablation of TNF-R1 or TNF-R2 reduced the number of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labelling (TUNEL)-positive apoptotic epithelial cells in the affected colons compared with WT TNBS-instilled controls, which might be due to the heightened ratio of Bcl-2/Bax and reduced activity of nuclear factor (NF)-κB. These findings suggest that either TNF-R1 or TNF-R2 plays a pathogenic role in the pathology of colitis and TNF signalling via TNF-R1 or TNF-R2 alone is not sufficient for inducing mucosal damage.

  4. Association of the Met-196-Arg variation of human tumor necrosis factor receptor 2 (TNFR2) with paranoid schizophrenia.

    Science.gov (United States)

    Thabet, Sihem; Ben Nejma, Mouna; Zaafrane, Ferid; Gaha, Lotfi; Ben Salem, Kamel; Romdhane, Abdelaziz; Nour, Mohamed; Jrad, Besma Bel Hadj

    2011-03-01

    Research has provided strong evidence for oligodendrocyte and myelin-related genes dysfunction in schizophrenia. Several studies have suggested abnormalities in the expression of myelin-related genes including tumor necrosis factor receptor 2 (TNFR2) involved in the neurodegeneration and remyelination. In order to further assess the role of TNFR2 in schizophrenia, we examined a functional bi-allelic polymorphism associated with an impaired NF-KB signaling and cell survival. In the present case/control study, 220 patients with schizophrenia and 176 healthy controls were genotyped by RFLP-PCR for the T/G polymorphism at the position 676 in exon 6 of the TNFR2 gene. We found a trend towards over-representation of TNFR2 676G in the patients compared to the controls (p=0.19 and 0.09 respectively). Interestingly, when we evaluated the association between this genetic polymorphism and the clinical variables of schizophrenia, our findings indicated that the frequencies of the G/G genotype and the G allele were significantly higher in paranoid (p=0.014 and p=0.012 respectively) and adult-onset paranoid (p=0.004 and p=0.004 respectively) schizophrenia patient group compared to the controls. The potential association was confirmed by a logistic regression model only for development of the paranoid form of schizophrenia (p=0.022) indicating a substantially increased risk for paranoid schizophrenia with inheritance of the TNFR2(G) allele. In conclusion, this polymorphism in TNFR2 or a gene in proximity seems to be associated specifically with paranoid schizophrenia, at least in the Tunisian population. A replication of our findings in other and larger populations could be of particular importance to establish TNFR2 as one of the susceptibility genes of paranoid schizophrenia.

  5. Expression and purification of a natural N-terminal pre-ligand assembly domain of tumor necrosis factor receptor 1 (TNFR1 PLAD) and preliminary activity determination.

    Science.gov (United States)

    Cao, Jin; Meng, Fang; Gao, Xiangdong; Dong, Hongxia; Yao, Wenbing

    2011-04-01

    A domain at the NH(2) terminal (N-terminal) of tumor necrosis factor receptor (TNFR) termed the pre-ligand binding assembly domain (PLAD). The finding that PLAD can mediate a selective TNFR assembly in previously researches provides a novel target to the prevention of TNFR signaling in immune-mediated inflammatory diseases (IMID). In this study, a natural N-terminal TNFR1 PLAD was obtained for the first time through the methods of GST-tag fusion protein expression and enterokinase cleavage. After purification with a Q Sepharose Fast Flow column, a natural N-terminal TNFR1 PLAD which purity was up to 95%, was obtained and was identified using Nano LC-ECI-MS/MS. Secondary structure analysis of PLAD was carried out using circular dichroism spectra (CD). After that, the TNFR1 PLAD in vitro anti-TNFα activity and the specific TNFR1 affinity were determined. The results proved that the natural N-terminal TNFR1 PLAD can selectively inhibit TNFα bioactivity mainly through TNFR1. It infers an effective and safe strategy for treating variety of IMID with a low risk of side effects in future.

  6. Identification and characterization of tumor necrosis factor receptor (TNFR)-associated factor 3 from humphead snapper, Lutjanus sanguineus.

    Science.gov (United States)

    Cai, Jia; Xia, Hongli; Huang, Yucong; Tang, Jufen; Jian, Jichang; Wu, Zaohe; Lu, Yishan

    2015-10-01

    Tumor necrosis factor receptor (TNFR)-associated factor 3(TRAF3) is a key regulator in TNFR and Toll-like receptor (TLRs)/RIG-I-like receptors (RLRs) signal pathway. Here, a TRAF3 gene (Ls-TRAF3, GenBank Accession No: KJ789921) is cloned from humphead snapper (Lutjanus sanguineus). The Ls-TRAF3 cDNA contains an open reading frame of 1788 bp, which encodes a polypeptide of 595 amino acids. The deduced amino acid of Ls-TRAF3 possesses a RING finger, two TRAF-type zinc fingers, a coiled-coil and a MATH domain. Ls-TRAF3 protein shares high identities with other known TRAF3 proteins. In healthy fish, Ls-TRAF3 transcripts were broadly expressed in all examined tissues with highest expression levels in spleen, liver and head kidney. Quantitative real-time PCR (qRT-PCR) analysis revealed that Ls-TRAF3 could be induced by bacteria or viral PAMP poly I:C stimulation in vivo. Here, we also showed Ls-TRAF3 that, positively regulated IRF3 and Mx upon poly I:C stimuli, whereas prevented production of proinflammatory cytokine IL-6 after LPS injection. Moreover, over-expression of wide type (WT) Ls-TRAF3 and truncated forms, including ΔZinc finger 1, ΔZinc finger 2 and Δcoiled-coil suppressed NF-κB activity significantly, whereas the inhibitory effect of NF-κB was partially impaired when the RING finger or MATH domain deletion, suggesting the latter was more important for downstream signal transduction. Taken together, these results implicated that Ls-TRAF3 might play regulatory roles in immune response to pathogen invasion.

  7. TNF receptor-associated factor-2 binding site is involved in TNFR75-dependent enhancement of TNFR55-induced cell death

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    TNF recepter-55 is the main mediator of TNF-induced apoptosis. TNF receptor-75-dependent induction or enhancement of cytotoxicity has been explained by intracellular signaling, “ligand passing”, or induction of endogenous TNF. To study the function of human TNF receptor-75 (hTR75) and the interaction between human TNF receptor-55 (hTR55) and hTR75 in hTNFc-induced cytotoxicity, Hep-2 cells were transfected with bicistronic expression vector of hTR75 and its deletion mutants genes. hTNFα-induced cytotoxicity was determined by crystal violet colorimetric method. The expression of hTR75 and its deletion mutants in Hep-2 cells was demonstrated by RT-PCR and indirect ELISA. We found that the overexpressed hTR75 could significantly increase the susceptibility of Hep-2 cells to hTNFα which especiαlly required TRAF2 binding site. hTR75 could not only mediate partial hTNFα-induced cytotoxicity independently but also fulfill an accessory role in enhancing or synergizing hTR55-mediated cytotoxicity.

  8. Differences between disease-associated endoplasmic reticulum aminopeptidase 1 (ERAP1) isoforms in cellular expression, interactions with tumour necrosis factor receptor 1 (TNF-R1) and regulation by cytokines.

    Science.gov (United States)

    Yousaf, N; Low, W Y; Onipinla, A; Mein, C; Caulfield, M; Munroe, P B; Chernajovsky, Y

    2015-05-01

    Endoplasmic reticulum aminopeptidase 1 (ERAP1) processes peptides for major histocompatibility complex (MHC) class I presentation and promotes cytokine receptor ectodomain shedding. These known functions of ERAP1 may explain its genetic association with several autoimmune inflammatory diseases. In this study, we identified four novel alternatively spliced variants of ERAP1 mRNA, designated as ΔExon-11, ΔExon-13, ΔExon-14 and ΔExon-15. We also observed a rapid and differential modulation of ERAP1 mRNA levels and spliced variants in different cell types pretreated with lipopolysaccharide (LPS). We have studied three full-length allelic forms of ERAP1 (R127-K528, P127-K528, P127-R528) and one spliced variant (ΔExon-11) and assessed their interactions with tumour necrosis factor receptor 1 (TNF-R1) in transfected cells. We observed variation in cellular expression of different ERAP1 isoforms, with R127-K528 being expressed at a much lower level. Furthermore, the cellular expression of full-length P127-K528 and ΔExon-11 spliced variant was enhanced significantly when co-transfected with TNF-R1. Isoforms P127-K528, P127-R528 and ΔExon-11 spliced variant associated with TNF-R1, and this interaction occurred in a region within the first 10 exons of ERAP1. Supernatant-derived vesicles from transfected cells contained the full-length and ectodomain form of soluble TNF-R1, as well as carrying the full-length ERAP1 isoforms. We observed marginal differences between TNF-R1 ectodomain levels when co-expressed with individual ERAP1 isoforms, and treatment of transfected cells with tumour necrosis factor (TNF), interleukin (IL)-1β and IL-10 exerted variable effects on TNF-R1 ectodomain cleavage. Our data suggest that ERAP1 isoforms may exhibit differential biological properties and inflammatory mediators could play critical roles in modulating ERAP1 expression, leading to altered functional activities of this enzyme.

  9. Requirement for Tumor Necrosis Factor Receptor 2 Expression on Vascular Cells To Induce Experimental Cerebral Malaria

    OpenAIRE

    Stoelcker, Benjamin; Hehlgans, Thomas; Weigl, Karin; Bluethmann, Horst; Grau, Georges E.; Männel, Daniela N

    2002-01-01

    Using tumor necrosis factor receptor type 2 (TNFR2)-deficient mice and generating bone marrow chimeras which express TNFR2 on either hematopoietic or nonhematopoietic cells, we demonstrated the requirement for TNFR2 expression on tissue cells to induce lethal cerebral malaria. Thus, TNFR2 on the brain vasculature mediates tumor necrosis factor-induced neurovascular lesions in experimental cerebral malaria.

  10. Interleukin-10 and soluble tumor necrosis factor receptors in cerebrospinal fluid of children with bacterial meningitis

    NARCIS (Netherlands)

    Kornelisse, R.F.; Savelkoul, H.F.J.; Mulder, P.H.G.; Suur, M.H.; Straaten, van der P.J.C.; Heijden, van der A.J.; Sukhai, R.N.; Hählen, K.; Neijens, H.J.; Groot, de R.

    1996-01-01

    The antiinflammatory mediators interleukin (IL)-10 and soluble tumor necrosis factor (TNF) receptors p55 (sTNFR-55) and sTNFR-75 in cerebrospinal fluid (CSF) from 37 children with bacterial meningitis were studied. CSF concentrations of IL-10, sTNFR-55, and sTNFR-75 and of the proinflammatory cytoki

  11. Soluble forms of tumor necrosis factor receptors (TNF-Rs). The cDNA for the type I TNF-R, cloned using amino acid sequence data of its soluble form, encodes both the cell surface and a soluble form of the receptor

    DEFF Research Database (Denmark)

    Nophar, Y; Kemper, O; Brakebusch, C

    1990-01-01

    found to have effects characteristic of TNF, including stimulating phosphorylation of specific cellular proteins. Oligonucleotide probes designed on the basis of the NH2-terminal amino acid sequence of TBPI were used to clone the cDNA for the structurally related cell surface type 1 TNF-R. It is notable...... that although this receptor can signal the phosphorylation of cellular proteins, it appears from its amino acid sequence to be devoid of intrinsic protein kinase activity. The extracellular domain of the receptor is composed of four internal cysteine-rich repeats, homologous to structures repeated four times...... of structure, did not suggest any identity between this protein and the extracellular domain of the type I TNF-R. CHO cells transfected with type I TNF-R cDNA produced both cell surface and soluble forms of the receptor. The receptor produced by CHO cells was recognized by several monoclonal antibodies against...

  12. A TRAF2 binding independent region of TNFR2 is responsibl for TRAF2 depletion and enhancement of cytotoxicity driven b TNFR1

    Science.gov (United States)

    Cabal-Hierro, Lucía; Noelia, Artime; Iglesias, Julián; Miguel A., Prado; Ugarte-Gil, Lore; Pedro, Casado; Fernández-García, Belén; Darnay, Bryant G.; Lazo, Pedro S.

    2014-01-01

    Tumor Necrosis Factor (TNF) interacts with two receptors known as TNFR1 and TNFR2. TNFR1 activation may result in either cell proliferation or cell death. TNFR2 activates Nuclear Factor-kappaB (NF-kB) and c-Jun N-terminal kinase (JNK) which lead to transcriptional activation of genes related to cell proliferation and survival. This depends on the binding of TNF Receptor Associated Factor 2 (TRAF2) to the receptor. TNFR2 also induces TRAF2 degradation. In this work we have investigated the structural features of TNFR2 responsible for inducing TRAF2 degradation and have studied the biological consequences of this activity. We show that when TNFR1 and TNFR2 are co-expressed, TRAF2 depletion leads to an enhanced TNFR1 cytotoxicity which correlates with the inhibition of NF-kB. NF-kB activation and TRAF2 degradation depend of different regions of the receptor since TNFR2 mutants at amino acids 343-349 fail to induce TRAF2 degradation and have lost their ability to enhance TNFR1-mediated cell death but are still able to activate NF-kB. Moreover, whereas NF-kB activation requires TRAF2 binding to the receptor, TRAF2 degradation appears independent of TRAF2 binding. Thus, TNFR2 mutants unable to bind TRAF2 are still able to induce its degradation and to enhance TNFR1-mediated cytotoxicity. To test further this receptor crosstalk we have developed a system stably expressing in cells carrying only endogenous TNFR1 the chimeric receptor RANK-TNFR2, formed by the extracellular region of RANK (Receptor activator of NF-kB) and the intracellular region of TNFR2.This has made possible to study independently the signals triggered by TNFR1 and TNFR2. In these cells TNFR1 is selectively activated by soluble TNF (sTNF) while RANK-TNFR2 is selectively activated by RANKL. Treatment of these cells with sTNF and RANKL leads to an enhanced cytotoxicity. PMID:24318359

  13. Modulation of PKC signaling and induction of apoptosis through suppression of reactive oxygen species and tumor necrosis factor receptor 1 (TNFR1): key role of quercetin in cancer prevention.

    Science.gov (United States)

    Maurya, Akhilendra Kumar; Vinayak, Manjula

    2015-11-01

    Cancer cells are characterized by increased production of reactive oxygen species (ROS) and an altered redox environment as compared to normal cells. Continuous accumulation of ROS triggers oxidative stress leading to hyper-activation of signaling pathways that promote cell proliferation, survival, and metabolic adaptation to the tumor microenvironment. Therefore, antioxidants are proposed to contribute to cancer prevention. Protein kinase C (PKC) is a crucial regulator of diverse cellular processes and contributes to cancer progression. The activation of PKC is partially dependent on ROS signaling. In the present study, cancer preventive activity of natural flavonoid quercetin is analyzed in ascite cells of Dalton's lymphoma-bearing mice. The total ROS level and activity of PKC were downregulated after quercetin treatment in lymphoma-bearing mice. Quercetin modulates the expression of almost all isozymes of classical, novel, and atypical PKC as well as downregulates the level and expression of PKCα. Further, quercetin improves apoptotic potential, as observed by the levels of caspase 3, caspase 9, PARP, PKCδ, and nuclear condensation. Additionally, quercetin reduces cell survival and promotes death receptor-mediated apoptosis via differential localization of the TNFR1 level in ascite cells. The overall result suggests the cancer preventive activity of quercetin via the induction of apoptosis and modulates PKC signaling with the reduction of oxidative stress in ascite cells of lymphoma-bearing mice.

  14. Anti-inflammatory effects of tumour necrosis factor (TNF)-alpha are mediated via TNF-R2 (p75) in tolerogenic transforming growth factor-beta-treated antigen-presenting cells.

    Science.gov (United States)

    Masli, Sharmila; Turpie, Bruce

    2009-05-01

    Exposure of macrophages to transforming growth factor (TGF)-beta is known to alter their functional phenotype such that antigen presentation by these cells leads to tolerance rather than an inflammatory immune response. Typically, eye-derived antigen-presenting cells (APCs) exposed to TGF-beta in the local environment are known to induce a form of peripheral tolerance and protect the eye from inflammatory immune effector-mediated damage. In response to TGF-beta, APCs increase their expression of tumour necrosis factor (TNF)-alpha and TNF receptor 2 (TNF-R2). Although TNF-alpha has been implicated in tolerance and the associated regulation of the inflammatory immune response, its source and the receptors involved remain unclear. In this report we determined the contribution of TNF-alpha and TNF-R2 expressed by TGF-beta-treated APCs to their anti-inflammatory tolerogenic effect. Our results indicate that APC-derived TNF-alpha is essential for the ability of APCs to regulate the immune response and their IL-12 secretion. Moreover, in the absence of TNF-R2, APCs exposed to TGF-beta failed to induce tolerance or regulatory cells known to participate in this tolerance. Also, blocking of TNF-R1 signalling enhanced the ability of the APCs to secrete increased TGF-beta in response to TGF-beta exposure. Together our results support an anti-inflammatory role of TNF-alpha in regulation of an immune response by TGF-beta-treated APCs and suggest that TNF-R2 contributes significantly to this role.

  15. The role of N-glycan modification of TNFR1 in inflammatory microglia activation.

    Science.gov (United States)

    Han, Lijian; Zhang, Dongmei; Tao, Tao; Sun, Xiaolei; Liu, Xiaojuan; Zhu, Guizhou; Xu, Zhiwei; Zhu, Liang; Zhang, Yu; Liu, Wangrui; Ke, Kaifu; Shen, Aiguo

    2015-12-01

    Accumulating evidences demonstrated that microglia activation and the autocrine loop of tumor necrosis factor-α (TNFα) greatly contribute to the pathogenesis of several CNS diseases. TNFα exerts its biological effects by interacting with two different receptors: TNF receptor 1 (TNFR1) and TNFR2. The classic proinflammatory activity of TNFα is mainly mediated by TNFR1. In the present study, we found that TNFR1 was modificated by N-glycosylation on Asn151 and Asn202 in microglia. The N-glycosylation of TNFR1 could facilitate its capability of binding to TNFα and further promote the formation of TNFα autocrine loop in microglia stimulated by TNFα, resulting in excessive microglia activation and CNS inflammation. All these processes were related to TNFR1-mediated NF-κB pathways. Elimination of N-glycosylation did not affect the subcellular transportation and cell surface localization of TNFR1, but suppressed ligand-binding affinity. These findings indicated that the N-glycosylation of TNFR1 played an important role during microglia activation in CNS inflammation. By this study, we aimed to provide some valuable experimental evidence for a better understanding of the significance of protein glycosylation in microglia inflammatory activation and CNS disease.

  16. Etk/Bmx as a tumor necrosis factor receptor type 2-specific kinase: role in endothelial cell migration and angiogenesis.

    Science.gov (United States)

    Pan, Shi; An, Ping; Zhang, Rong; He, Xiangrong; Yin, Guoyong; Min, Wang

    2002-11-01

    Tumor necrosis factor (TNF) is a cytokine that mediates many pathophysiologial processes, including angiogenesis. However, the molecular signaling involved in TNF-induced angiogenesis has not been determined. In this study, we examined the role of Etk/Bmx, an endothelial/epithelial tyrosine kinase involved in cell adhesion, migration, and survival in TNF-induced angiogenesis. We show that TNF activates Etk specifically through TNF receptor type 2 (TNFR2) as demonstrated by studies using a specific agonist to TNFR2 and TNFR2-deficient cells. Etk forms a preexisting complex with TNFR2 in a ligand-independent manner, and the association is through multiple domains (pleckstrin homology domain, TEC homology domain, and SH2 domain) of Etk and the C-terminal domain of TNFR2. The C-terminal 16-amino-acid residues of TNFR2 are critical for Etk association and activation, and this Etk-binding and activating motif in TNFR2 is not overlapped with the TNFR-associated factor type 2 (TRAF2)-binding sequence. Thus, TRAF2 is not involved in TNF-induced Etk activation, suggesting a novel mechanism for Etk activation by cytokine receptors. Moreover, a constitutively active form of Etk enhanced, whereas a dominant-negative Etk blocked, TNF-induced endothelial cell migration and tube formation. While most TNF actions have been attributed to TNFR1, our studies demonstrate that Etk is a TNFR2-specific kinase involved in TNF-induced angiogenic events.

  17. The brefeldin A-inhibited guanine nucleotide-exchange protein, BIG2, regulates the constitutive release of TNFR1 exosome-like vesicles.

    Science.gov (United States)

    Islam, Aminul; Shen, Xiaoyan; Hiroi, Toyoko; Moss, Joel; Vaughan, Martha; Levine, Stewart J

    2007-03-30

    The type I, 55-kDa tumor necrosis factor receptor (TNFR1) is released from cells to the extracellular space where it can bind and modulate TNF bioactivity. Extracellular TNFR1 release occurs by two distinct pathways: the inducible proteolytic cleavage of TNFR1 ectodomains and the constitutive release of full-length TNFR1 in exosome-like vesicles. Regulation of both TNFR1 release pathways appears to involve the trafficking of cytoplasmic TNFR1 vesicles. Vesicular trafficking is controlled by ADP-ribosylation factors (ARFs), which are active in the GTP-bound state and inactive when bound to GDP. ARF activation is enhanced by guanine nucleotide-exchange factors that catalyze replacement of GDP by GTP. We investigated whether the brefeldin A (BFA)-inhibited guanine nucleotide-exchange proteins, BIG1 and/or BIG2, are required for TNFR1 release from human umbilical vein endothelial cells. Effects of specific RNA interference (RNAi) showed that BIG2, but not BIG1, regulated the release of TNFR1 exosome-like vesicles, whereas neither BIG2 nor BIG1 was required for the IL-1beta-induced proteolytic cleavage of TNFR1 ectodomains. BIG2 co-localized with TNFR1 in diffusely distributed cytoplasmic vesicles, and the association between BIG2 and TNFR1 was disrupted by BFA. Consistent with the preferential activation of class I ARFs by BIG2, ARF1 and ARF3 participated in the extracellular release of TNFR1 exosome-like vesicles in a nonredundant and additive fashion. We conclude that the association between BIG2 and TNFR1 selectively regulates the extracellular release of TNFR1 exosome-like vesicles from human vascular endothelial cells via an ARF1- and ARF3-dependent mechanism.

  18. Reactive oxygen species mediate TNFR1 increase after TRPV1 activation in mouse DRG neurons

    Directory of Open Access Journals (Sweden)

    Westlund Karin N

    2009-06-01

    Full Text Available Abstract Background Transient receptor potential vanilloid subtype 1 (TRPV1 is activated by low pH/protons and is well known to be involved in hyperalgesia during inflammation. Tumor necrosis factor α (TNF-α, a proinflammatory cytokine, is involved in nociceptive responses causing hyperalgesia through TNF receptor type 1 (TNFR1 activation. Reactive oxygen species (ROS production is also prominently increased in inflamed tissue. The present study investigated TNFR1 receptors in primary cultured mouse dorsal root ganglion (DRG neurons after TRPV1 activation and the involvement of ROS. C57BL/6 mice, both TRPV1 knockout and wild type, were used for immunofluorescent and live cell imaging. The L4 and L5 DRGs were dissected bilaterally and cultured overnight. TRPV1 was stimulated with capsaicin or its potent analog, resiniferatoxin. ROS production was measured with live cell imaging and TNFR1 was detected with immunofluorescence in DRG primary cultures. The TRPV1 knockout mice, TRPV1 antagonist, capsazepine, and ROS scavenger, N-tert-Butyl-α-phenylnitrone (PBN, were employed to explore the functional relationship among TRPV1, ROS and TNFR1 in these studies. Results The results demonstrate that TRPV1 activation increases TNFR1 receptors and ROS generation in primary cultures of mouse DRG neurons. Activated increases in TNFR1 receptors and ROS production are absent in TRPV1 deficient mice. The PBN blocks increases in TNFR1 and ROS production induced by capsaicin/resiniferatoxin. Conclusion TRPV1 activation increases TNFR1 in cultured mouse DRG neurons through a ROS signaling pathway, a novel sensitization mechanism in DRG neurons.

  19. Effects of propyl gallate on interaction between TNF-α and sTNFR-I using an affinity biosensor

    Institute of Scientific and Technical Information of China (English)

    Jing LI; Jia-dong HUANG; Bao-yan WU; Qiang CHEN

    2005-01-01

    Aim: To study the effects of propyl gallate on the interaction of tumor necrosis factor-α (TNF-α) with its soluble receptor, sTNFR-I. Methods: Interactions between TNF-α and sTNFR-I were analyzed using an IAsys biosensor. sTNFR-I was immobilized on the carboxymethyl dextran (CMD) surface of the IAsys biosensor cuvettes, and TNF-α preincubated with different concentrations of propyl gallate was added to the cuvettes. The resonant angle shift caused by the binding between TNF-α and sTNFR-I was then recorded. Results: sTNFR-I was immobilized on the CMD surface at a density of 2.76 ng/mm2. TNF-α then bound the immobilized sTNFR-I specifically, and propyl gallate was able to enhance the binding between TNF-α and sTNFR-I in a dose-dependent manner. Conclusion:The binding between TNF-α and sTNFR-I is one of the targets that propyl gallate can act on in vivo. The IAsys biosensor offers a new clue as to the study on the mechanisms of action of propyl gallate.

  20. Tumor Necrosis Factor Receptor 1 Expression Is Upregulated in Dendritic Cells in Patients with Chronic HCV Who Respond to Therapy

    Directory of Open Access Journals (Sweden)

    Raul Cubillas

    2010-01-01

    Full Text Available The present studies assessed the level of tumor necrosis factor receptor (TNFR expression in peripheral blood mononuclear cells (PBMCs subsets from patients with chronic HCV undergoing interferon /ribavirin-based therapy (Ifn/R. Methods. TNFR family member mRNA expression was determined using quantitative real-time PCR assays (RTPCRs in PBMC from 39 HCV+ patients and 21 control HCV− patients. Further subset analysis of HCV + patients (untreated (U, sustained virological responders (SVR, and nonresponders (NR/relapsers (Rel PBMC was performed via staining with anti-CD123, anti-CD33, anti-TNFR1 or via RTPCR for TNFR1 mRNA. Results. A similar level of TNFR1 mRNA in PBMC from untreated HCV+ genotype 1 patients and controls was noted. TNFR1 and TNFR2 mRNA levels in PBMC from HCV+ patients with SVR were statistically different than levels in HCV(− patients. A significant difference was noted between the peak values of TNFR1 of the CD123+ PBMC isolated from SVR and the NR/Rel. Conclusion. Upregulation of TNFR1 expression, occurring in a specific subset of CD123+ dendritic cells, appeared in HCV+ patients with SVR.

  1. The role of tumor necrosis factor-α and TNF-α receptors in cerebral arteries following cerebral ischemia in rat

    DEFF Research Database (Denmark)

    Maddahi, Aida; Kruse, Lars S; Chen, Qing-Wen

    2011-01-01

    Tumour necrosis factor-α (TNF-α) is a pleiotropic pro-inflammatory cytokine, which is rapidly upregulated in the brain after injury. TNF-α acts by binding to its receptors, TNF-R1 (p55) and TNF-R2 (p75), on the cell surface. The aim of this study was first to investigate if there is altered expre...

  2. The role of tumor necrosis factor-α and TNF-α receptors in cerebral arteries following cerebral ischemia in rat

    DEFF Research Database (Denmark)

    Maddahi, Aida; Kruse, Lars S; Chen, Qing-Wen

    2011-01-01

    Tumour necrosis factor-a (TNF-a) is a pleiotropic pro-inflammatory cytokine, which is rapidly upregulated in the brain after injury. TNF-a acts by binding to its receptors, TNF-R1 (p55) and TNF-R2 (p75), on the cell surface. The aim of this study was first to investigate if there is altered expre...

  3. Functional discrepancies between tumor necrosis factor and lymphotoxin alpha explained by trimer stability and distinct receptor interactions

    DEFF Research Database (Denmark)

    Schuchmann, M; Hess, S; Bufler, P;

    1995-01-01

    interaction with the human p55TNFR. This was demonstrated in NIH 3T3 cells transfected with the human p55TNFR, where cytotoxicity is mediated exclusively by the transfected receptor. Although the p55ATNFR had virtually identical affinities for TNF and LT alpha, as defined by Scatchard analysis......Tumor necrosis factor (TNF) and lymphotoxin alpha (LT alpha) are closely related cytokines which bind with nearly identical affinities to the same pair of cell surface receptors, p55 and p75TNFR. Therefore it is assumed that TNF and LT alpha are redundant cytokines. This study, however...

  4. Circulating cathepsin-S levels correlate with GFR decline and sTNFR1 and sTNFR2 levels in mice and humans

    Science.gov (United States)

    Steubl, Dominik; Kumar, Santhosh V.; Tato, Maia; Mulay, Shrikant R.; Larsson, Anders; Lind, Lars; Risérus, Ulf; Renders, Lutz; Heemann, Uwe; Carlsson, Axel C.; Ärnlöv, Johan; Anders, Hans-Joachim

    2017-01-01

    Cardiovascular complications determine morbidity/mortality in chronic kidney disease (CKD). We hypothesized that progressive CKD drives the release of cathepsin-S (Cat-S), a cysteine protease that promotes endothelial dysfunction and cardiovascular complications. Therefore, Cat-S, soluble tumor-necrosis-factor receptor (sTNFR) 1/2 and glomerular filtration rate (GFR) were measured in a CKD mouse model, a German CKD-cohort (MCKD, n = 421) and two Swedish community-based cohorts (ULSAM, n = 764 and PIVUS, n = 804). Association between Cat-S and sTNFR1/2/GFR was assessed using multivariable linear regression. In the mouse model, Cat-S and sTNFR1/2 concentrations were increased following the progressive decline of GFR, showing a strong correlation between Cat-S and GFR (r = −0.746, p < 0.001) and Cat-S and sTNFR1/sTNFR2 (r = 0.837/0.916, p < 0.001, respectively). In the human cohorts, an increase of one standard deviation of estimated GFR was associated with a decrease of 1.008 ng/ml (95%-confidence interval (95%-CI) −1.576–(−0.439), p < 0.001) in Cat-S levels in MCKD; in ULSAM and PIVUS, results were similar. In all three cohorts, Cat-S and sTNFR1/sTNFR2 levels were associated in multivariable linear regression (p < 0.001). In conclusion, as GFR declines Cat-S and markers of inflammation-related endothelial dysfunction increase. The present data indicating that Cat-S activity increases with CKD progression suggest that Cat-S might be a therapeutic target to prevent cardiovascular complications in CKD. PMID:28240259

  5. Expression of membrane receptor for tumour necrosis factor on human blood lymphocytes.

    Science.gov (United States)

    Zola, H; Flego, L; Weedon, H

    1993-08-01

    Using a monoclonal antibody against the human p75 tumour necrosis factor receptor (TNFR-I) combined with a high-sensitivity immunofluorescence flow cytometric procedure, a proportion of peripheral blood lymphocytes can be shown to express TNFR-I constitutively. Approximately 50% of peripheral blood lymphocytes consisting mostly of CD4 cells and including most CD45R0-positive cells, express TNFR-I. Receptor expression is increased by a variety of activation signals. Only a minority (up to 30%) of tonsil B cells express measurable levels of TNFR-I. The tonsil B cells which express TNFR-I include both cells with a germinal centre cell phenotype and cells with the phenotype of the follicular mantle zone. Activation of B cells with anti-immunoglobulin, alone or in combination with interleukin-4 or interleukin-2, increases receptor expression, particularly in cells with the phenotype of mantle zone cells. The functional significance of constitutive expression of TNFR by blood and tissue lymphocytes is discussed.

  6. Superoxide anion-induced pain and inflammation depends on TNFα/TNFR1 signaling in mice.

    Science.gov (United States)

    Yamacita-Borin, Fabiane Y; Zarpelon, Ana C; Pinho-Ribeiro, Felipe A; Fattori, Victor; Alves-Filho, Jose C; Cunha, Fernando Q; Cunha, Thiago M; Casagrande, Rubia; Verri, Waldiceu A

    2015-09-25

    Inhibition of tumor necrosis factor-alpha (TNFα) and superoxide anion production reduces inflammation and pain. The present study investigated whether superoxide anion-induced pain depends on TNFα signaling and the role of superoxide anion in TNFα-induced hyperalgesia to clarify the interrelation between these two mediators in the context of pain. Intraplantar injection of a superoxide anion donor (potassium superoxide) induced mechanical hyperalgesia (0.5-5h after injection), neutrophil recruitment (myeloperoxidase activity), and overt pain-like behaviors (paw flinching, paw licking, and abdominal writhings) in wild-type mice. Tumor necrosis factor receptor 1 deficiency (TNFR1-/-) and treatment of wild-type mice with etanercept (a soluble TNFR2 receptor that inhibits TNFα actions) inhibited superoxide anion-induced pain-like behaviors. TNFR1(-/-) mice were also protected from superoxide anion donor-induced oxidative stress, suggesting the role of this pathway in the maintenance of oxidative stress. Finally, we demonstrated that Apocynin (an NADPH oxidase inhibitor) or Tempol (a superoxide dismutase mimetic) treatment inhibited TNFα-induced paw mechanical hyperalgesia and neutrophil recruitment (myeloperoxidase activity). These results demonstrate that TNFα/TNFR1 signaling is important in superoxide anion-triggered pain and that TNFα/TNFR1 signaling amplifies the oxidative stress triggered by superoxide anion, which contributes to sustaining pain and inflammation.

  7. Lack of Proinflammatory Cytokine Interleukin-6 or Tumor Necrosis Factor Receptor-1 Results in a Failure of the Innate Immune Response after Bacterial Meningitis

    Directory of Open Access Journals (Sweden)

    Lea-Jessica Albrecht

    2016-01-01

    Full Text Available The most frequent pathogen that causes bacterial meningitis is the Gram-positive bacterium Streptococcus pneumoniae. By entering the brain, host cells will be activated and proinflammatory cytokines like interleukin-6 (IL-6 and tumor necrosis factor-α (TNF-α are released. The goal of the current study was to examine the interaction between IL-6 and TNFR1 as receptor for TNF-α and the innate immune response in vivo in a model of Streptococcus pneumoniae-induced meningitis. For the experiments IL-6−/−, TNFR1−/−, and TNFR1-IL-6−/− KO mice were used. Our results revealed higher mortality rates and bacterial burden after infection in TNFR1−/−, IL-6−/−, and TNFR1-IL-6−/− mice and a decreased immune response including lower neutrophil infiltration in the meninges of TNFR1−/− and TNFR1-IL-6−/− mice in contrast to IL-6−/− and wild type mice. Furthermore, the increased mortality of TNFR1−/− and TNFR1-IL-6−/− mice correlated with decreased glial cell activation compared to IL-6−/− or wild type mice after pneumococcal meningitis. Altogether, the results show the importance of TNFR1 and IL-6 in the regulation of the innate immune response. The lack of TNFR1 and IL-6 results in higher mortality by weakened immune defence, whereas the lack of TNFR1 results in more severe impairment of the innate immune response than the lack of IL-6 alone.

  8. Disease causing mutations in the TNF and TNFR superfamilies: Focus on molecular mechanisms driving disease

    NARCIS (Netherlands)

    A.A. Lobito; T.L. Gabriel; J.P. Medema; F.C. Kimberley

    2011-01-01

    The tumor necrosis factor (TNF) and TNF receptor (TNFR) superfamilies comprise multidomain proteins with diverse roles in cell activation, proliferation and cell death. These proteins play pivotal roles in the initiation, maintenance and termination of immune responses and have vital roles outside t

  9. Inhibition of Paeoniflorin on TNF-α-induced TNF-α Receptor Type Ⅰ/Nuclear Factor-κB Signal Transduction in Endothelial Cells%芍药苷对TNF-α诱导的内皮细胞TNFR1/NF-κB信号通路的抑制作用

    Institute of Scientific and Technical Information of China (English)

    马淑慧; 王海芳; 刘金连; 霍雪萍; 赵向绒; 曹情雯; 刘勤社

    2016-01-01

    目的 研究芍药苷(paeoniflorin,PAE)对TNF-α诱导小鼠肾动脉内皮细胞TNFR1介导信号通路的抑制作用,试探讨其作用的分子机制.方法 体外培养小鼠动脉内皮细胞.采用Western blot方法检测正常组(无血清培养基培养)、TNF-α组(无血清培养基培养2h加TNF-α30ng/mL 6 h)、PAE低浓度组(PAE 0.8 μmol/L培养2h加TNF-α 30ng/mL 6 h)、PAE中浓度组(PAE 8μmol/L培养2h加TNF-α30ng/mL 6 h)及PAE高浓度组(PAE 80 μmol/L培养2h加TNF-α30ng/mL 6 h)细胞间黏附分子-1(intercellular cell adhesion molecule-1,ICAM-1)的蛋白表达;以免疫荧光法检测正常组(无血清培养基培养)、TNF-α组(无血清培养基培养2h加TNF-α 30ng/mL 45 min)、PAE高浓度组(PAE 80 tμmol/L培养2h加TNF-α 30ng/mL 45 min)核因子κB(nuclear factor-κB,NF-κB)的核转位;以Western blot法检测正常组(无血清培养基培养)及PAE高浓度组(PAE 80 μmol/L培养2h)ph-ERK和ph-p38表达;Western blot法检测正常组(无血清培养基培养)、TNF-α组(无血清培养基培养2h加TN F-α 30ng/mL30 min)、PAE高浓度组PAE 80μmol/L培养2h加TNF-αr 30ng/mL 30 min)、p38抑制剂组(SB组,p38抑制剂SB238025 25 μmol/L预处理30 min,PAE 80 μmol/L处理2h,最后TNF-α 30 ng/mL30 min)及ERK抑制剂组(PD组,ERK抑制剂PD98059 50 μmol/L处理30 min,PAE 80 μmol/L处理2h,最后TNF-α30 ng/mL 30 min)IκBα蛋白表达.结果 与正常组比较,TNF-α组ICAM-1蛋白表达明显升高(P<0.01);与TNF-α组比较,PAE高浓度组的ICAM-1表达受到显著抑制(P<0.05).PAE高浓度组ph-p38及ph-ERK蛋白表达水平明显较正常组升高(P<0.05).与正常组比较,TNF-αα组IκBα表达水平下降(P<0.01).与TNF-α组比较,PAE高浓度组可显著抑制TNF-α诱导的IκBα蛋白降解(P<0.01),SB组可显著阻断PAE对IκBα蛋白降解的抑制作用(P<0.05).正常组中NF-κB/p65信号主要位于胞浆中,TNF-α组在TNF-α刺激45 min可诱导NF-κB/p65由胞浆向细胞核转

  10. Tumor necrosis factor alpha affect hydrocortisone expression in mice adrenal cortex cells mainly through tumor necrosis factor alpha-receptor 1

    Institute of Scientific and Technical Information of China (English)

    XIA Hai-ming; FANG Yuan; HUANG Pei-lin

    2011-01-01

    Background Tumor necrosis factor alpha (TNF-α) is important in promoting relative adrenal insufficiency (RAI) due to systemic inflammatory response syndrome (SIRS).We identified the TNF-α receptor involved in the inhibition of adrenal corticotrophin (ACTH)-stimulated hydrocortisone release by studying the expression of TNF-α receptors in adrenal cortex Y1 cells and the effect of downregulating TNF receptors on ACTH-stimulated hydrocortisone release.Methods We used real-time PCR and immunocytochemistry to evaluate the expression of TNF receptors on Y1 cells.TNF-receptor 1 (TNF-R1) DNA fragments corresponding to the short hairpin RNA (shRNA)-sequences were synthesized and cloned into pcDNATM 6.2-GW/EmGFP expression vector.Knockdown efficiency of TNF-R1 expression was evaluated in miRNA transfected and mock-miRNA transfected Y1 cells by quantitative real-time PCR (Q-PCR).Hydrocortisone expression levels were determined in TNF-R1-knockdown and control Y1 cells treated with TNF-α and ACTH.Results Mouse adrenal cortex Y1 cells were positive for type I TNF-R1,but not type Ⅱ TNF-receptor (TNF-R2).Blocking TNF-R1 expression resulted in loss of TNF-α-mediated inhibition of ACTH-stimulated hydrocortisone expression,suggesting a role for the TNF-R1 related signaling pathway in ACTH-stimulated hydrocortisone synthesis.Conclusion The inhibitory effect of TNF-α on ACTH-stimulated hydrocortisone synthesis was mediated via TNF-R1 in adrenal cortex.

  11. TNFR1 and TNFR2 differentially mediate TNF-α-induced inflammatory responses in rheumatoid arthritis fibroblast-like synoviocytes.

    Science.gov (United States)

    Zhang, Hongfeng; Xiao, Weiguo

    2017-04-01

    TNF-α has long been implicated in the progression of rheumatoid arthritis (RA). However, how the receptors of TNF-α, namely TNFR1 and TNFR2, mediate TNF-α-induced inflammatory responses in fibroblast-like synoviocytes (FLS) in RA has not been elucidated. In the present study, primary FLS cells were isolated from RA patients and treated with TNF-α in vitro. The exogenous TNF-α induced the expression and release of endogenous TNF-α in FLS. In addition, TNF-α led to gradual downregulation of TNFR1 following 1 h treatment. By contrast, the expression of TNFR2 was markedly upregulated after 12 h treatment with TNF-α. Moreover, following TNF-α treatment, the expression of interleukin (IL)-2, IL-6, and IL-8 was gradually increased with time, but their mRNA levels dropped significantly at 48 h. We further investigated the differential functions of TNFR1 and TNFR2 in FLS by conducting siRNA-mediated knockdown. The TNF-α autocrine was inhibited to a greater extent in TNFR1-silenced FLS compared with TNFR2-silenced FLS. Silencing of TNFR1, not TNFR2, activated intrinsic apoptosis and inhibited TNF-α-induced cytokine production in FLS. These results suggest that TNFR1 is the major pro-inflammatory mediator of TNF-α in FLS, whereas TNFR2, which is upregulated in response to prolonged TNF-α stimulation, may act as an immunosuppressor in FLS for the prevention of overwhelming inflammatory reactions.

  12. Circulating levels of tumor necrosis factor-alpha receptor 2 are increased in heart failure with preserved ejection fraction relative to heart failure with reduced ejection fraction: evidence for a divergence in pathophysiology.

    Directory of Open Access Journals (Sweden)

    Brendan N Putko

    Full Text Available BACKGROUND: Various pathways have been implicated in the pathogenesis of heart failure (HF with preserved ejection fraction (HFPEF. Inflammation in response to comorbid conditions, such as hypertension and diabetes, may play a proportionally larger role in HFPEF as compared to HF with reduced ejection fraction (HFREF. METHODS AND RESULTS: This study investigated inflammation mediated by the tumor necrosis factor-alpha (TNFα axis in community-based cohorts of HFPEF patients (n = 100, HFREF patients (n = 100 and healthy controls (n = 50. Enzyme-linked immunosorbent assays were used to investigate levels of TNFα, its two receptors (TNFR1 and TNFR2, and a non-TNFα cytokine, interleukin-6 (IL-6, in plasma derived from peripheral blood samples. Plasma levels of TNFα and TNFR1 were significantly elevated in HFPEF relative to controls, while levels of TNFR2 were significantly higher in HFPEF than both controls and HFREF. TNFα, TNFR1 and TNFR2 were each significantly associated with at least two of the following: age, estimated glomerular filtration rate, hypertension, diabetes, smoking, peripheral vascular disease or history of atrial fibrillation. TNFR2 levels were also significantly associated with increasing grade of diastolic dysfunction and severity of symptoms in HFPEF. CONCLUSIONS: Inflammation mediated through TNFα and its receptors, TNFR1 and TNFR2, may represent an important component of a comorbidity-induced inflammatory response that partially drives the pathophysiology of HFPEF.

  13. 潜伏活性的可溶性肿瘤坏死因子受体Ⅰ靶向治疗子宫内膜异位症的实验研究%Role of a latent soluble TNF receptor type Ⅰ (hsTNFR Ⅰ) fusion protein in targeted treatment of endometriosis

    Institute of Scientific and Technical Information of China (English)

    熊宙芳; 胡沙; 王泽华

    2010-01-01

    Objective To construct a latent human soluble tumor necrosis factor receptor Ⅰ(hsTNFR Ⅰ) using the latency associated protein (LAP) of transforming growth factor-β1 (TGF-β1) fused via a matrix metalloproteinase (MMP) cleavage site to hsTNFR Ⅰ so as to detect the latent biological activity of LAP-MMP-hsTNFR Ⅰ fusion protein. Methods A double-stranded deoxyoligonucleotide coding for MMP cleavage site was cloned into plasmid pcDNA3.1. LAP and hsTNFR Ⅰ cDNA were then inserted into both two sides of MMP cleavage site. After being transferred by LAP-MMP-hsTNFR Ⅰ fusion gene with liposome, the expression of fusion protein in COS-7 cells was detected by RT-PCR and Western blot. The inhibitory effect of fusion protein upon cytotoxicity of TNF-α was detected by methyl thiazolyl tetrazolium (MTT) assay before and after the fusion protein incubated in MMP or peritoneal fluid from endometriosis patients. Results The recombinant plasmid LAP-MMP-hsTNFR Ⅰ -pcDNA3. 1 was constructed successfully and was expressed effectively in COS-7 cells. The MTT assay showed that there was no difference in the mortality rote of L929 cells between LAP-MMP-hsTNFR Ⅰ -pcDNA3.1 and empty vector transfection groups (P>0.05). The mortality rates of L929 cells with 800 ng/L TNF-α in LAP-MMP-hsTNFR Ⅰ -pcDNA3.1 transfection group after incubation with MMP or peritoneal fluid from endometriosis patients were(44.5 ±2.4) % and(33.8±1.9) % respectively. And it was lower than the pre-incubation period (58.1± 2.4) %(P0.05).但在800 ng/L肿瘤坏死因子(TNF)-α作用下,重组质粒转染上清与MMP和子宫内膜异位症患者的腹腔液孵育后,L929细胞死亡率分别为(44.5±2.4)%和(33.8±1.9)%,显著低于孵育前(58.1±2.4)%,(P<0.05). 结论 LAP-MMP-hsTNFR Ⅰ重组融合蛋白的生物学活性可被LAP有效潜伏,并可被MMP和子宫内膜异位症患者的腹腔液激活,可应用于子宫内膜异位症的局部靶向治疗.

  14. Analysis of cognition, motor performance and anxiety in young and aged tumor necrosis factor alpha receptor 1 and 2 deficient mice

    NARCIS (Netherlands)

    Naude, Petrus J W; Dobos, Nikoletta; van der Meer, Dennis; Mulder, Cornelis; Pawironadi, Kim G D; den Boer, Johan A; van der Zee, Eddy A; Luiten, Paulus; Eisel, Ulrich L M

    2014-01-01

    TNF-α plays important functional roles in the central nervous system during normal physiological circumstances via intricate signaling mechanisms between its receptors, TNF receptor 1 (TNFR1) and TNF receptor 2 (TNFR2). Although the roles of TNFR1 and TNFR2 in the diseased brain have received

  15. Soluble tumor necrosis factor receptor 1 and 2 predict outcomes in advanced chronic kidney disease: a prospective cohort study.

    Directory of Open Access Journals (Sweden)

    Nathalie Neirynck

    Full Text Available Soluble tumor necrosis factor receptors 1 (sTNFR1 and 2 (sTNFR2 have been associated to progression of renal failure, end stage renal disease and mortality in early stages of chronic kidney disease (CKD, mostly in the context of diabetic nephropathy. The predictive value of these markers in advanced stages of CKD irrespective of the specific causes of kidney disease has not yet been defined. In this study, the relationship between sTNFR1 and sTNFR2 and the risk for adverse cardiovascular events (CVE and all-cause mortality was investigated in a population with CKD stage 4-5, not yet on dialysis, to minimize the confounding by renal function.In 131 patients, CKD stage 4-5, sTNFR1, sTNFR2 were analysed for their association to a composite endpoint of all-cause mortality or first non-fatal CVE by univariate and multivariate Cox proportional hazards models. In the multivariate models, age, gender, CRP, eGFR and significant comorbidities were included as covariates.During a median follow-up of 33 months, 40 events (30.5% occurred of which 29 deaths (22.1% and 11 (8.4% first non-fatal CVE. In univariate analysis, the hazard ratios (HR of sTNFR1 and sTNFR2 for negative outcome were 1.49 (95% confidence interval (CI: 1.28-1.75 and 1.13 (95% CI: 1.06-1.20 respectively. After adjustment for clinical covariables (age, CRP, diabetes and a history of cardiovascular disease both sTNFRs remained independently associated to outcomes (HR: sTNFR1: 1.51, 95% CI: 1.30-1.77; sTNFR2: 1.13, 95% CI: 1.06-1.20. A subanalysis of the non-diabetic patients in the study population confirmed these findings, especially for sTNFR1.sTNFR1 and sTNFR2 are independently associated to all-cause mortality or an increased risk for cardiovascular events in advanced CKD irrespective of the cause of kidney disease.

  16. Tumor necrosis factor-α regulates glucocorticoid synthesis in the adrenal glands of Trypanosoma cruzi acutely-infected mice. the role of TNF-R1.

    Directory of Open Access Journals (Sweden)

    Silvina R Villar

    Full Text Available Adrenal steroidogenesis is under a complex regulation involving extrinsic and intrinsic adrenal factors. TNF-α is an inflammatory cytokine produced in response to tissue injury and several other stimuli. We have previously demonstrated that TNF-R1 knockout (TNF-R1(-/- mice have a dysregulated synthesis of glucocorticoids (GCs during Trypanosoma cruzi acute infection. Since TNF-α may influence GCs production, not only through the hypothalamus-pituitary axis, but also at the adrenal level, we now investigated the role of this cytokine on the adrenal GCs production. Wild type (WT and TNF-R1(-/- mice undergoing acute infection (Tc-WT and Tc-TNF-R1(-/- groups, displayed adrenal hyperplasia together with increased GCs levels. Notably, systemic ACTH remained unchanged in Tc-WT and Tc-TNF-R1(-/- compared with uninfected mice, suggesting some degree of ACTH-independence of GCs synthesis. TNF-α expression was increased within the adrenal gland from both infected mouse groups, with Tc-WT mice showing an augmented TNF-R1 expression. Tc-WT mice showed increased levels of P-p38 and P-ERK compared to uninfected WT animals, whereas Tc-TNF-R1(-/- mice had increased p38 and JNK phosphorylation respect to Tc-WT mice. Strikingly, adrenal NF-κB and AP-1 activation during infection was blunted in Tc-TNF-R1(-/- mice. The accumulation of mRNAs for steroidogenic acute regulatory protein and cytochrome P450 were significantly increased in both Tc-WT and Tc-TNF-R1(-/- mice; being much more augmented in the latter group, which also had remarkably increased GCs levels. TNF-α emerges as a potent modulator of steroidogenesis in adrenocortical cells during T. cruzi infection in which MAPK pathways, NF-κB and AP-1 seem to play a role in the adrenal synthesis of pro-inflammatory cytokines and enzymes regulating GCs synthesis. These results suggest the existence of an intrinsic immune-adrenal interaction involved in the dysregulated synthesis of GCs during murine Chagas

  17. Comparison of the effect of lipopolysaccharide on tumor necrosis factor α (TNF-α) secretion and TNF and TNFR1 mRNA levels in feline endometrium throughout the estrous cycle during pyometra and after medroxyprogesterone acetate treatment.

    Science.gov (United States)

    Jursza-Piotrowska, Ewelina; Siemieniuch, Marta J

    2016-08-25

    Endotoxins released by Gram-negative bacteria are potent stimulators of tumor necrosis factor α (TNF-α) production. The objectives of this study were to evaluate plasma levels of TNF-α, TNF-α secretion, and mRNA levels of TNF and TNF-α receptor type 1 (TNFR1) following exposure to lipopolysaccharide (LPS). For this, we used cultured endometrial cells or organ cultures, throughout the estrous cycle, after hormone treatment with medroxyprogesterone acetate (MPA), and during pyometra. Plasma TNF-α concentrations were increased in animals at estrus (P < 0.05) compared to other groups. In the LPS-challenged endometrium, secretion of TNF-α by tissues collected during estrus increased (P < 0.001) compared to that of other groups. LPS, alone or combined with TNF-α, upregulated TNF gene expression in the feline endometrium at diestrus (P < 0.001 for both treatments), in queens treated short-term with MPA (P < 0.01 and P < 0.05, respectively) and in queens treated long-term with MPA (P < 0.01 and P < 0.001, respectively). During pyometra, TNF and TNFR1 mRNA were increased only after tissues were challenged with TNF-α and LPS (P < 0.001 and P < 0.01, respectively). When cultured endometrial cells were challenged with LPS, the concentration of TNF-α increased only in epithelial cells after 4 h and 12 h (P < 0.05 and P < 0.01, respectively). Since LPS did not affect stromal cells, but TNF-α increased its own transcript after 2 h (P < 0.01), 4 h (P < 0.05) and 12 h (P < 0.001), we assume that stromal cells are not directly involved in pathogen recognition, as was the case for epithelial cells.

  18. Insulin-like growth factor-binding protein-5 (IGFBP-5) inhibits TNF-{alpha}-induced NF-{kappa}B activity by binding to TNFR1

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Jae Ryoung; Huh, Jae Ho; Lee, Yoonna; Lee, Sang Il [Molecular Therapy Research Center, Sungkyunkwan University, Seoul 135-710 (Korea, Republic of); Rho, Seung Bae [Research Institute, National Cancer Center, Goyang-si, Gyeonggi-do 411-769 (Korea, Republic of); Lee, Je-Ho, E-mail: jeholee@gmail.com [Molecular Therapy Research Center, Sungkyunkwan University, Seoul 135-710 (Korea, Republic of); Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2011-02-25

    Research highlights: {yields} Binding assays demonstrated that secreted- and cellular-IGFBP-5 interacted with TNFR1. {yields} The interaction between IGFBP-5 and TNFR1 was inhibited by TNF-{alpha} and was blocked TNF-{alpha}-activated NF-{kappa}B activity. {yields} IGFBP-5 interacted with TNFR1 through its N- and L-domains but the binding of L-domain to TNFR1 was blocked by TNF-{alpha}. {yields} Competition between the L-domain of IGFBP-5 and TNF-{alpha} blocked TNF-{alpha}-induced NF-{kappa}B activity. {yields} This study suggests that the L-domain of IGFBP-5 is a novel TNFR1 ligand that functions as a competitive TNF-{alpha} inhibitor. -- Abstract: IGFBP-5 is known to be involved in various cell phenomena such as proliferation, differentiation, and apoptosis. However, the exact mechanisms by which IGFBP-5 exerts its functions are unclear. In this study, we demonstrate for the first time that IGFBP-5 is a TNFR1-interacting protein. We found that ectopic expression of IGFBP-5 induced TNFR1 gene expression, and that IGFBP-5 interacted with TNFR1 in both an in vivo and an in vitro system. Secreted IGFBP-5 interacted with GST-TNFR1 and this interaction was blocked by TNF-{alpha}, demonstrating that IGFBP-5 might be a TNFR1 ligand. Furthermore, conditioned media containing secreted IGFBP-5 inhibited PMA-induced NF-{kappa}B activity and IL-6 expression in U-937 cells. Coimmunoprecipitation assays of TNFR1 and IGFBP-5 wild-type and truncation mutants revealed that IGFBP-5 interacts with TNFR1 through its N- and L-domains. However, only the interaction between the L-domain of IGFBP-5 and TNFR1 was blocked by TNF-{alpha} in a dose-dependent manner, suggesting that the L-domain of IGFBP-5 can function as a TNFR1 ligand. Competition between the L-domain of IGFBP-5 and TNF-{alpha} resulted in inhibition of TNF-{alpha}-induced NF-{kappa}{Beta} activity. Taken together, our results suggest that the L-domain of IGFBP-5 is a novel TNFR1 ligand that functions as a competitive TNF

  19. TNFR-Fc减轻LPS所致小鼠ALI炎症反应损伤%Protective role of TNFR-Fc in mouse acute lung injury induced by lipopolysaccharide

    Institute of Scientific and Technical Information of China (English)

    袁伟锋; 李理; 徐虹; 黄文杰

    2011-01-01

    目的:评价肿瘤坏死因子受体-Fc融合蛋白(TNFR-Fc)能否有效下调炎症反应而减轻急性肺损伤(ALI)小鼠的肺组织破坏.方法:小鼠随机分为脂多糖(LPS)组、TNFR-Fc+LPS组和对照组.气管内滴入LPS复制ALI小鼠模型,TNFR-Fc组在滴入LPS前24 h腹膜腔注射TNFR-Fc (0.4 mg/kg),在滴入LPS后2 h收集标本,检测肺湿/干重、肺泡蛋白含量与肺组织病理评分;ELISA法检测血清TNF-α浓度及检测肺泡灌洗液与血清IL-1β、IL-6、IL-10与IFN-γ浓度.结果:TNFR-Fc显著降低血清TNF-α浓度(P<0.05),轻度降低肺湿/干重比例,显著降低BALF蛋白浓度(P<0.05),显著降低ALI评分数值(P<0.05).TNFR-Fc显著降低致炎症细胞因子IL-6在BALF(P<0.05)与血清(P<0.05)中的浓度,轻度提高BALF中IL-10浓度(P>0.05),但其差异不显著,亦能显著提高血清IL-10浓度(P<0.05).IL-1β与IFN-γ水平处理前后变化不显著.结论:TNFR-Fc中和ALI中过度表达的TNF-α,下调以IL-6为代表的炎症反应,减轻ALI的肺组织破坏.%AIM: Acute lung injury ( ALI ) is associated with excessive inflammation caused by high tumor necrosis factor α( TNF - α ) concentration. We hypothesized that anti - TNF - a therapy would have beneficial effects on mouse ALI model via down - regulating the inflammation. METHODS: Lipopolysaccharide( LPS, 5 mg/kg ) was intratra-cheally administered to BALB/c mice ( 8 ~ 10 weeks old ). Twenty - four hours before LPS treatment, the mice were intrap-eritoneally injected with TNF receptor - Fc fusion protein( TNFR - Fc ) once at a dose of 0.4 mg/kg. Wet to dry ratio of the lung tissues and protein concentration in bronchoalveolar lavage fluid( BALF ) were detected. The histological changes of the lung tissues were also observed to evaluate lung injury. The concentration of TNF - a. In serum as well as interleukin - 1 β( IL - 1 β ), IL - 6, IL - 10 and interferon γ(IFN - γ ) in BALF and serum were measured by ELISA. RESULTS: TNFR - Fc

  20. TNFR 2 M196R Polymorphism and Acne Vulgaris in Han Chinese:A Case-control Study

    Institute of Scientific and Technical Information of China (English)

    田黎明; 谢红付; 杨婷; 胡耀华; 李吉; 王玮蓁

    2010-01-01

    In this case-control study,the relationship between M196R(676 T→G) variant in exon 6 of tumor necrosis factor receptor type 2(TNFR2) gene and genetic susceptibility of acne vulgaris in Han Chinese was investigated.A total of 93 acne vulgaris patients and 90 healthy subjects from Han Chinese ethnic group were enrolled in this study.Polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) technique was adopted to analyze the single nucleotide polymorphisms(SNPs) of TNFR2 M196R gene,and to ...

  1. Tumor necrosis factor receptor-1 is essential for LPS-induced sensitization and tolerance to oxygen-glucose deprivation in murine neonatal organotypic hippocampal slices.

    Science.gov (United States)

    Markus, Tina; Cronberg, Tobias; Cilio, Corrado; Pronk, Cornelis; Wieloch, Tadeusz; Ley, David

    2009-01-01

    Inflammation and ischemia have a synergistic damaging effect in the immature brain. The role of tumor necrosis factor (TNF) receptors 1 and 2 in lipopolysaccharide (LPS)-induced sensitization and tolerance to oxygen-glucose deprivation (OGD) was evaluated in neonatal murine hippocampal organotypic slices. Hippocampal slices from balb/c, C57BL/6 TNFR1(-/-), TNFR2(-/-), and wild-type (WT) mice obtained at P6 were grown in vitro for 9 days. Preexposure to LPS immediately before OGD increased propidium iodide-determined cell death in regions CA1, CA3, and dentate gyrus from 4 up to 48 h after OGD (P<0.001). Extending the time interval between LPS exposure and OGD to 72 h resulted in tolerance, that is reduced neuronal cell death after OGD (P<0.05). Slices from TNFR1(-/-) mice showed neither LPS-induced sensitization nor LPS-induced tolerance to OGD, whereas both effects were present in slices from TNFR2(-/-) and WT mice. Cytokine secretion (TNFalpha and interleukin-6) during LPS exposure was decreased in TNFR1(-/-) slices and increased in TNFR2(-/-) as compared with WT slices. We conclude that LPS induces sensitization or tolerance to OGD depending on the time interval between exposure to LPS and OGD in murine hippocampal slice cultures. Both paradigms are dependent on signaling through TNFR1.

  2. TNF-α and TNFR1 responses to recovery therapies following acute resistance exercise

    Directory of Open Access Journals (Sweden)

    Jeremy R. Townsend

    2015-02-01

    Full Text Available The purpose of this investigation was to compare the effect of two commonly used therapeutic modalities a. neuromuscular electrical stimulation (NMES and b. cold water immersion (CWI on circulating tumor necrosis factor alpha (TNF-α and monocyte TNF-α receptor (TNFR1 expression following intense acute resistance exercise and subsequent recovery. Thirty (n=30 resistance trained men (22.5 ± 2.7 y performed an acute heavy resistance exercise protocol on three consecutive days followed by one of three recovery methods (CON, NMES, and CWI. Circulating TNF-α levels were assayed and TNFR1 expression on CD14+ monocytes was measured by flow cytometry measured PRE, immediately post (IP, 30-minutes post (30M, 24 hours post (24H, and 48 hours post (48H exercise. Circulating TNF-α was elevated at IP (p = 0.001 and 30M (p = 0.005 and decreased at 24H and 48H recovery from IP in CON (p = 0.015 and CWI (p = 0.011. TNF-α did not significantly decrease from IP during recovery in NMES. TNFR1 expression was elevated (p < 0.001 at 30M compared to PRE and all other time points. No significant differences between groups were observed in TNFR1 expression. During recovery (24H, 48H from muscle damaging exercise, NMES treatment appears to prevent the decline in circulating TNF-α observed during recovery in those receiving no treatment or CWI.

  3. Relationship between serum tumor necrosis factor receptor-2 concentration and periodontal destruction in patients with type 2 diabetes: Cross-sectional study

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    Matić-Petrović Sanja

    2016-01-01

    Full Text Available Introduction. The role of tumor necrosis factor-α (TNFα is well documented in pathogenesis of chronic periodontitis (CP and type 2 diabetes (T2D. Considering short half-life of TNFα, tumor necrosis factor receptor-2 (TNFR2 is used as prosperous surrogate marker of TNFα activity. Objective. The aim was to detect TNFR2 serum concentration and correlate it with periodontal destruction in patients with diagnosed T2D and nondiabetics. Methods. The study included 85 patients divided into three groups: T2D + CP (group T2D, n = 34; nondiabetics + CP (Group PD, n = 27; and healthy controls (group HC, n = 24. T2D was diagnosed according to WHO criteria (2013 and periodontitis was diagnosed using International Workshop for a Classification of Periodontal Diseases and Conditions criteria (1999. TNFR2 level was measured by enzyme-linked immunosorbent assay (ELISA. Results. There was no difference in TNFR2 level among the groups (Kruskal-Wallis, p = 0.482. Significant correlation (Pearson’s correlation coefficient was observed between clinical attachment loss (CAL and TNFR2 concentration in PD group (rp = -0.460, p = 0.016. In T2D group, correlations were observed between TNFR2 concentration and CAL (rp = 0.363, p = 0.005 and periodontal inflamed surface area (PISA (rp = 0.345, p = 0.046 and periodontal epithelial surface area (PESA (rp = 0.578, p = 0.000. Conclusion. Higher concentration of TNFR2 was associated with higher CAL, PESA, and PISA scores in T2D group. Contrary to that, nondiabetics with higher values of CAL exhibited lower concentration of TNFR2, presenting potential protective effect on periodontal destruction. These results imply that diabetes may alter TNFR2 secretion originated from periodontium. [Projekat Ministarstva nauke Republike Srbije, br. 41008

  4. Loss of the oncogenic phosphatase PRL-3 promotes a TNF-R1 feedback loop that mediates triple-negative breast cancer growth.

    Science.gov (United States)

    Gari, H H; DeGala, G D; Lucia, M S; Lambert, J R

    2016-08-15

    Stimulating tumor cell senescence and apoptosis are proven methods for therapeutically combating cancer. However, senescence and apoptosis are conventionally viewed as parallel, not sequential, processes. We have discovered that the metastasis-promoting phosphatase, PRL-3, is transcriptionally regulated by the NF-ĸB pathway in triple-negative breast cancer (TNBC) cells, and that PRL-3 knockdown elicits an autocrine tumor necrosis factor receptor 1 (TNF-R1) feedback loop that results in TNBC cell senescence followed by apoptosis. Knockdown of PRL-3 leads to rapid G1 cell cycle arrest and induction of a strong TNFα cytokine response that promotes a period of cellular senescence through TNF-R1-mediated activation of NF-ĸB. Senescent PRL-3 knockdown cells subsequently underwent apoptosis as a result of increased TNF-R1 signaling through the TNFα-associated extrinsic death pathway, shunting signaling away from the NF-ĸB cascade. These data suggest that TNF-R1 signaling dynamically re-programs after PRL-3 knockdown, from sustaining cell senescence through NF-ĸB to promoting apoptosis through TNF-R1 internalization and caspase-8 activation. The molecular mechanisms that determine the survival-death balance of TNF-R1 signaling are poorly understood, despite the fact that TNF-R1 has been extensively studied. Our results describe PRL-3 knockdown as a novel survival-death balance modifier of the TNF-R1 pathway, and show that senescent TNBC tumor cells can be sensitized to undergo apoptosis in a sequential manner.

  5. Elevated CSF levels of TACE activity and soluble TNF receptors in subjects with mild cognitive impairment and patients with Alzheimer's disease

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    Blennow Kaj

    2011-10-01

    Full Text Available Abstract We recently reported that expression levels of tumor necrosis factor (TNF receptors, TNFR1 and TNFR2, are significantly changed in the brains and cerebrospinal fluid (CSF with Alzheimer's disease (AD. Moreover, we also found that, in an Alzheimer's mouse model, genetic deletion of TNF receptor (TNFR1 reduces amyloid plaques and amyloid beta peptides (Aβ production through β-secretase (BACE1 regulation. TNF-α converting enzyme (TACE/ADAM-17 does not only cleave pro- TNF-α but also TNF receptors, however, whether the TACE activity was changed in the CSF was not clear. In this study, we examined TACE in the CSF in 32 AD patients and 27 age-matched healthy controls (HCs. Interestingly, we found that TACE activity was significantly elevated in the CSF from AD patients compared with HCs. Furthermore, we also assayed the CSF levels of TACE cleaved soluble forms of TNFR1 and TNFR2 in the same patients. We found that AD patients had higher levels of both TACE cleaved soluble TNFR1 (sTNFR1 and TNFR2 (sTNFR2 in the CSF compared to age- and gender-matched healthy controls. Levels of sTNFR1 correlated strongly with the levels of sTNFR2 (rs = 0.567-0.663, p

  6. Increased TNFR1 expression and signaling in injured peripheral nerves of mice with reduced BACE1 activity.

    Science.gov (United States)

    Liu, Lijuan; Fissel, John A; Tasnim, Aniqa; Borzan, Jasenka; Gocke, Anne; Calabresi, Peter A; Farah, Mohamed H

    2016-09-01

    Hematogenous macrophages remove myelin debris from injured peripheral nerves to provide a micro-environment conducive to axonal regeneration. Previously, we observed that injured peripheral nerves from Beta-site APP Cleaving Enzyme 1 (BACE1) knockout (KO) mice displayed earlier influx of and enhanced phagocytosis by macrophages when compared to wild-type (WT) mice. These observations suggest that BACE1 might regulate macrophage influx into distal stumps of injured nerves. To determine through which pathway BACE1 influences macrophage influx, we used a mouse inflammation antibody array to assay the expression of inflammation-related proteins in injured nerves of BACE1 KO and WT mice. The most significant change was in expression of tumor necrosis factor receptor 1 (TNFR1) in the distal stump of injured BACE1 KO nerves. Western blotting of protein extracts confirmed increased expression of TNFR1 and its downstream transcriptional factor NFκB in the BACE1 KO distal stumps. Additionally, treatment of WT mice with a BACE1 inhibitor resulted in increased TNFR1 expression and signaling in the distal stump of injured nerves. Exogenous TNFα increased nuclear translocation of p65 NFκB in BACE1 KO tissue and cultured fibroblasts compared with control WT. BACE1 regulates TNFR1 expression at the level of gene expression and not through proteolytic processing. The accelerated macrophage influx in injured nerves of BACE1 KO mice correlates with increased expression and signaling via TNFR1, indicating a link between BACE1 activity and TNFR1 expression/signaling that might contribute to repair of the injured nervous system.

  7. Tumor necrosis factor receptors support murine hematopoietic progenitor function in the early stages of engraftment.

    Science.gov (United States)

    Pearl-Yafe, Michal; Mizrahi, Keren; Stein, Jerry; Yolcu, Esma S; Kaplan, Ofer; Shirwan, Haval; Yaniv, Isaac; Askenasy, Nadir

    2010-07-01

    Tumor necrosis factor (TNF) family receptors/ligands are important participants in hematopoietic homeostasis, in particular as essential negative expansion regulators of differentiated clones. As a prominent injury cytokine, TNF-alpha has been traditionally considered to suppress donor hematopoietic stem and progenitor cell function after transplantation. We monitored the involvement of TNF receptors (TNF-R) 1 and 2 in murine hematopoietic cell engraftment and their inter-relationship with Fas. Transplantation of lineage-negative (lin(-)) bone marrow cells (BMC) from TNF receptor-deficient mice into wild-type recipients showed defective early engraftment and loss of durable hematopoietic contribution upon recovery of host hematopoiesis. Consistently, cells deficient in TNF receptors had reduced competitive capacity as compared to wild-type progenitors. The TNF receptors were acutely upregulated in bone marrow (BM)-homed donor cells (wild-type) early after transplantation, being expressed in 60%-75% of the donor cells after 6 days. Both TNF receptors were detected in fast cycling, early differentiating progenitors, and were ubiquitously expressed in the most primitive progenitors with long-term reconstituting potential (lin(-)c-kit(+) stem cell antigen (SCA)-1(+)). BM-homed donor cells were insensitive to apoptosis induced by TNF-alpha and Fas-ligand and their combination, despite reciprocal inductive cross talk between the TNF and Fas receptors. The engraftment supporting effect of TNF-alpha is attributed to stimulation of progenitors through TNF-R1, which involves activation of the caspase cascade. This stimulatory effect was not observed for TNF-R2, and this receptor did not assume redundant stimulatory function in TNFR1-deficient cells. It is concluded that TNF-alpha plays a tropic role early after transplantation, which is essential to successful progenitor engraftment.

  8. Soluble tumor necrosis factor receptor 1 and tissue inhibitor of metalloproteinase-1 in hemolytic uremic syndrome with encephalopathy.

    Science.gov (United States)

    Shiraishi, Masahiro; Ichiyama, Takashi; Matsushige, Takeshi; Iwaki, Takuma; Iyoda, Kuniaki; Fukuda, Ken; Makata, Haruyuki; Matsubara, Tomoyo; Furukawa, Susumu

    2008-05-30

    Enterohemorrhagic Escherichia coli (EHEC) induces hemorrhagic colitis and hemolytic uremic syndrome (HUS). Morbidity and mortality are increased in HUS patients with neurologic complications. To determine the pathogenesis of the central nervous system (CNS) involvement in HUS by EHEC, we determined the serum concentrations of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), soluble TNF receptor 1 (sTNFR1), IL-10, interferon-gamma (IFN-gamma), IL-2, IL-4, soluble E-selectin (sE-selectin), matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinase-1 (TIMP-1) during the acute stage in children with HUS with or without CNS involvement. Serum concentrations of IL-6, IL-10, sTNFR1, sE-selectin, MMP-9, and TIMP-1, but not TNF-alpha, IFN-gamma, IL-2, or IL-4, were significantly higher in patients with HUS with encephalopathy compared with controls. Serum IL-6, sTNFR1 and TIMP-1 concentrations were significantly higher in patients with HUS with encephalopathy compared with those with HUS without encephalopathy (P=0.031, P=0.005, and P=0.007, respectively) and those with acute colitis without HUS (P=0.011, Pencephalopathy. Our preliminary study suggests that serum IL-6, sTNFR1 and TIMP-1 levels, particularly sTNFR1 and TIMP-1, are important for predicting neurological complications in patients with HUS.

  9. PEGylated PLGA Nanoparticles as Tumor Ecrosis FactorReceptor Blocking Peptide Carriers: Preparation,Characterization and Release in vitro

    Institute of Scientific and Technical Information of China (English)

    LIU Wei; YANG Anshu; LI Zhuoya; XU Huibi; YANG Xiangliang

    2007-01-01

    To assess the merits of PEGylated poly (lactic-co-glycolic acid) (PEG-PLGA) nanoparticles as drug carriers for tumor necrosis factorreceptor blocking peptide (TNFR-BP), PEG-PLGA copolymer,which could be used to prepare the stealth nanoparticles, was synthesized with methoxypolyethyleneglycol,DL-lactide and glycolide. The structure of PEG-PLGA was confirmed with 1H-NMR and FT-IR spectroscopy,and the molecular weight (MW) was determined by gel permeation chromatography. Fluorescent FITC-TNFR-BP was chosen as model protein and encapsulated within PEG-PLGA nanoparticles using the double emulsion method. Atomic force microscopy and photon correlation spectroscopy were employed to characterize the stealth nanoparticles fabricated for morphology, size with polydispersity index and zeta potential. Encapsulation efficiency (EE) and the release of FITC-TNFR-BP in nanoparticles in vitro were measured by the fluorescence measurement. The stealth nanoparticles were found to have the mean diameter less than 270 nm and zeta potential less than-20 mV. In all nanoparticle formulations, more than 45% of EE were obtained. FITC-TNFR-BP release from the PEG-PLGA nanoparticles exhibited a biphasic pattern, initial burst release and consequently sustained release. The experimental results show that PEG-PLGA nanoparticles possess the potential to develop as drug carriers for controlled release applications of TNFR-BP.

  10. TNF-R2 expression in acquired middle ear cholesteatoma Expressão do TNF-R2 no colesteatoma adquirido da orelha média

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    Rodrigo Faller Vitale

    2011-08-01

    Full Text Available Acquired middle ear cholesteatoma is a disease which promotes bone erosion resulting in potentially serious complications. The tumor necrosis factor alpha (TNF-α is present in cholesteatoma and it is related to bone erosion, as shown by different authors. To understand the aggressiveness characteristics of cholesteatoma is necessary, however, to better address the presence and distribution of their receptors. OBJECTIVE: To evaluate the expression of type 2 TNF-α receptor (TNF-R2 in fragments of cholesteatoma and correlate it to the degree of inflammation present. MATERIAL AND METHODS: observational cross-sectional study, which analyzed 33 fragments of cholesteatomas through histological analysis and immunohistochemistry (using as primary antibody to TNF-R2 LabVision® brand. The evaluation was performed by means of a qualitative and semi-quantitative agreement with the observed intensity. For statistical analysis we used the Fisher exact test and Spearman´s correlation coefficient (considered statistically significant when p O colesteatoma adquirido da orelha média promove erosão óssea, ocasionando complicações potencialmente graves. O fator de necrose tumoral alfa (TNF-α está presente no colesteatoma adquirido da orelha média e relaciona-se com a erosão óssea, como demonstraram diferentes autores. Para que se compreenda as características de agressividade do colesteatoma, é necessário que se estude a presença e a distribuição seus receptores. OBJETIVO: Avaliar a expressão do receptor tipo dois do TNF-α (TNF-R2 em fragmentos de colesteatoma e relacioná-lo com o grau de inflamação. MATERIAL E MÉTODOS: Estudo observacional do tipo transversal. Foram analisados 33 fragmentos de colesteatomas, submetidos à análise histológica e imunoistoquímica (utilizando o TNF-R2 da marca Labvision®. A avaliação foi realizada de forma qualitativa e semiquantitativa, de acordo com a intensidade observada. Para a análise estat

  11. Azadirachtin interacts with the tumor necrosis factor (TNF) binding domain of its receptors and inhibits TNF-induced biological responses.

    Science.gov (United States)

    Thoh, Maikho; Kumar, Pankaj; Nagarajaram, Hampathalu A; Manna, Sunil K

    2010-02-19

    The role of azadirachtin, an active component of a medicinal plant Neem (Azadirachta indica), on TNF-induced cell signaling in human cell lines was investigated. Azadirachtin blocks TNF-induced activation of nuclear factor kappaB (NF-kappaB) and also expression of NF-kappaB-dependent genes such as adhesion molecules and cyclooxygenase 2. Azadirachtin inhibits the inhibitory subunit of NF-kappaB (IkappaB alpha) phosphorylation and thereby its degradation and RelA (p65) nuclear translocation. It blocks IkappaB alpha kinase (IKK) activity ex vivo, but not in vitro. Surprisingly, azadirachtin blocks NF-kappaB DNA binding activity in transfected cells with TNF receptor-associated factor (TRAF)2, TNF receptor-associated death domain (TRADD), IKK, or p65, but not with TNFR, suggesting its effect is at the TNFR level. Azadirachtin blocks binding of TNF, but not IL-1, IL-4, IL-8, or TNF-related apoptosis-inducing ligand (TRAIL) with its respective receptors. Anti-TNFR antibody or TNF protects azadirachtin-mediated down-regulation of TNFRs. Further, in silico data suggest that azadirachtin strongly binds in the TNF binding site of TNFR. Overall, our data suggest that azadirachtin modulates cell surface TNFRs thereby decreasing TNF-induced biological responses. Thus, azadirachtin exerts an anti-inflammatory response by a novel pathway, which may be beneficial for anti-inflammatory therapy.

  12. The role of tumor necrosis factor-α and TNF-α receptors in cerebral arteries following cerebral ischemia in rat

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    Chen Qing-Wen

    2011-08-01

    Full Text Available Abstract Background Tumour necrosis factor-α (TNF-α is a pleiotropic pro-inflammatory cytokine, which is rapidly upregulated in the brain after injury. TNF-α acts by binding to its receptors, TNF-R1 (p55 and TNF-R2 (p75, on the cell surface. The aim of this study was first to investigate if there is altered expression of TNF-α and TNF-α receptors in cerebral artery walls following global or focal ischemia, and after organ culture. Secondly, we asked if the expression was regulated via activation of the MEK-ERK1/2 pathway. Methods The hypothesis was tested in vivo after subarachnoid hemorrhage (SAH and middle cerebral artery occlusion (MCAO, and in vitro by organ culture of isolated cerebral arteries. The localization and amount of TNF-α, TNF-α receptor 1 and 2 proteins were analysed by immunohistochemistry and western blot after 24 and 48 h of organ culture and at 48 h following SAH or MCAO. In addition, cerebral arteries were incubated for 24 or 48 h in the absence or presence of a B-Raf inhibitor (SB386023-b, a MEK- inhibitor (U0126 or an NF-κB inhibitor (IMD-0354, and protein expression evaluated. Results Immunohistochemistry revealed enhanced expression of TNF-α, TNF-R1 and TNF-R2 in the walls of cerebral arteries at 48 h after MCAO and SAH compared with control. Co-localization studies showed that TNF-α, TNF-R1 and TNF-R2 were primarily localized to the cell membrane and the cytoplasm of the smooth muscle cells (SMC. There was, in addition, some expression of TNF-R2 in the endothelial cells. Immunohistochemistry and western blot analysis showed that these proteins were upregulated after 24 and 48 h in culture, and this upregulation reached an apparent maximum at 48 h of organ culture. Treatment with U0126 significantly reduced the enhanced SMC expression of TNF-α, TNF-R1 and TNF-R2 immunoreactivities after 24 and 48 h of organ culture. The Raf and NF-κB inhibitors significantly reduced organ culture induced TNF-α expression

  13. TNF/TNFR1 signaling up-regulates CCR5 expression by CD8+ T lymphocytes and promotes heart tissue damage during Trypanosoma cruzi infection: beneficial effects of TNF-α blockade

    Directory of Open Access Journals (Sweden)

    Karina Kroll-Palhares

    2008-06-01

    Full Text Available In Chagas disease, understanding how the immune response controls parasite growth but also leads to heart damage may provide insight into the design of new therapeutic strategies. Tumor necrosis factor-alpha (TNF-α is important for resistance to acute Trypanosoma cruzi infection; however, in patients suffering from chronic T. cruzi infection, plasma TNF-α levels correlate with cardiomyopathy. Recent data suggest that CD8-enriched chagasic myocarditis formation involves CCR1/CCR5-mediated cell migration. Herein, the contribution of TNF-α, especially signaling through the receptor TNFR1/p55, to the pathophysiology of T. cruzi infection was evaluated with a focus on the development of myocarditis and heart dysfunction. Colombian strain-infected C57BL/6 mice had increased frequencies of TNFR1/p55+ and TNF-α+ splenocytes. Although TNFR1-/- mice exhibited reduced myocarditis in the absence of parasite burden, they succumbed to acute infection. Similar to C57BL/6 mice, Benznidazole-treated TNFR1-/- mice survived acute infection. In TNFR1-/- mice, reduced CD8-enriched myocarditis was associated with defective activation of CD44+CD62Llow/- and CCR5+ CD8+ lymphocytes. Also, anti-TNF-α treatment reduced the frequency of CD8+CCR5+ circulating cells and myocarditis, though parasite load was unaltered in infected C3H/HeJ mice. TNFR1-/- and anti-TNF-α-treated infected mice showed regular expression of connexin-43 and reduced fibronectin deposition, respectively. Furthermore, anti-TNF-α treatment resulted in lower levels of CK-MB, a cardiomyocyte lesion marker. Our results suggest that TNF/TNFR1 signaling promotes CD8-enriched myocarditis formation and heart tissue damage, implicating the TNF/TNFR1 signaling pathway as a potential therapeutic target for control of T. cruzi-elicited cardiomyopathy.

  14. TNF/TNFR1 signaling up-regulates CCR5 expression by CD8+ T lymphocytes and promotes heart tissue damage during Trypanosoma cruzi infection: beneficial effects of TNF-alpha blockade.

    Science.gov (United States)

    Kroll-Palhares, Karina; Silvério, Jaline Coutinho; Silva, Andrea Alice da; Michailowsky, Vladimir; Marino, Ana Paula; Silva, Neide Maria; Carvalho, Cristiano Marcelo Espinola; Pinto, Luzia Maria de Oliveira; Gazzinelli, Ricardo Tostes; Lannes-Vieira, Joseli

    2008-06-01

    In Chagas disease, understanding how the immune response controls parasite growth but also leads to heart damage may provide insight into the design of new therapeutic strategies. Tumor necrosis factor-alpha (TNF-alpha) is important for resistance to acute Trypanosoma cruzi infection; however, in patients suffering from chronic T. cruzi infection, plasma TNF-alpha levels correlate with cardiomyopathy. Recent data suggest that CD8-enriched chagasic myocarditis formation involves CCR1/CCR5-mediated cell migration. Herein, the contribution of TNF-alpha, especially signaling through the receptor TNFR1/p55, to the pathophysiology of T. cruzi infection was evaluated with a focus on the development of myocarditis and heart dysfunction. Colombian strain-infected C57BL/6 mice had increased frequencies of TNFR1/p55+ and TNF-alpha+ splenocytes. Although TNFR1-/- mice exhibited reduced myocarditis in the absence of parasite burden, they succumbed to acute infection. Similar to C57BL/6 mice, Benznidazole-treated TNFR1-/- mice survived acute infection. In TNFR1-/- mice, reduced CD8-enriched myocarditis was associated with defective activation of CD44+CD62Llow/- and CCR5+ CD8+ lymphocytes. Also, anti-TNF-alpha treatment reduced the frequency of CD8+CCR5+ circulating cells and myocarditis, though parasite load was unaltered in infected C3H/HeJ mice. TNFR1-/- and anti-TNF-alpha-treated infected mice showed regular expression of connexin-43 and reduced fibronectin deposition, respectively. Furthermore, anti-TNF-alpha treatment resulted in lower levels of CK-MB, a cardiomyocyte lesion marker. Our results suggest that TNF/TNFR1 signaling promotes CD8-enriched myocarditis formation and heart tissue damage, implicating the TNF/TNFR1 signaling pathway as a potential therapeutic target for control of T. cruzi-elicited cardiomyopathy.

  15. Dynamic distributions of tumor necrosis factor-alpha and its receptors in the red nucleus of rats with spared nerve injury.

    Science.gov (United States)

    Wang, Jing; Ding, Cui-Ping; Yu, Jing; Zeng, Xiao-Yan; Han, Shui-Ping; Wang, Jun-Yang

    2016-08-01

    Previous studies have demonstrated that tumor necrosis factor-alpha (TNF-α) in the red nucleus (RN) plays a facilitated role in the development of neuropathic pain, and its effect is transmitted through TNF-α receptor (TNFR) subtypes 1 and 2. Here, the dynamic distributions of TNF-α and TNFRs in the RN of rats with spared nerve injury (SNI) were investigated. Western blot analysis and immunofluorescence staining indicated that TNF-α was hardly expressed in the RN of normal rats but significantly increased at 1 week and peaked at 2 weeks after SNI. Neurons and oligodendrocytes showed TNF-α expression at both 1 week and 2 weeks after SNI, while astrocytes and microglia produced TNF-α later than neurons and oligodendrocytes starting at 2 weeks after SNI. TNFR1 was constitutively expressed in the RN of normal rats and significantly enhanced at 2 weeks but not 1 week after SNI; it was mainly localized in neurons, oligodendrocytes and microglia. Astrocytes were not immunopositive for TNFR1 under normal conditions and at 1 week after injury, but small amounts of astrocytes showed TNFR1 expression at 2 weeks after SNI. A low level of TNFR2 was expressed in the RN of normal rats, but it was significantly increased at 1 week and 2 weeks after SNI and localized in neurons and all three types of glia. These findings suggest that neurons and three types of glia in the RN all contribute to TNF-α production and participate in the initiation and/or maintenance of neuropathic pain induced by SNI. TNF-α exerts its effects in different types of cells maybe through different receptors, TNFR1 and/or TNFR2, in the different stages of neuropathic pain.

  16. Arecoline-induced death of human leukemia K562 cells is associated with surface up-modulation of TNFR2.

    Science.gov (United States)

    Chen, Ying-Jung; Chang, Long-Sen

    2012-05-01

    The goal of the present study is to explore the contribution of tumor necrosis factor-α (TNFα)-related pathway to the cytotoxicity of arecoline on human leukemia K562 cells. Arecoline treatment induced death of K562 cells and increased surface expression of TNFα, TNFR1, and TNFR2. Unlike that of TNFR1 mRNA, transcriptional levels of TNFα and TNFR2 mRNA increased in arecoline-treated cells. Moreover, arecoline-induced down-regulation of ADAM17 maturation was involved in surface up-modulation of TNFR1, TNFR2, and TNFα. Arecoline-elicited increase in intracellular Ca(2+) concentration was responsible for JNK/c-Jun pathway activation and ERK inactivation. Abolition of JNK/c-Jun pathway suppressed arecoline-induced increase in transcriptional level of TNFα and TNFR2 mRNA. TNFα and TNFR2 promoter luciferase activity and chromatin immunoprecipitating analyses revealed that c-Jun increasingly bound with TNFα and TNFR2 promoter upon arecoline treatment. Over-expression of constitutively active MEK1 abolished the effect of arecoline on suppressing ADAM17 maturation. Pretreatment with TNFR2 antibody abrogated arecoline-induced increased susceptibility of K562 cells for the cytotoxicity of TNFα and arecoline-induced cell death. Taken together, our data suggest that up-modulation of TNFR2 surface expression is associated with arecoline-induced death of K562 cells. Copyright © 2011 Wiley Periodicals, Inc.

  17. The expression of tumor necrosis factor-alpha, its receptors and steroidogenic acute regulatory protein during corpus luteum regression

    Directory of Open Access Journals (Sweden)

    Arfuso Frank

    2008-11-01

    Full Text Available Abstract Background Corpus luteum (CL regression is known to occur as two parts; functional regression when steroidogenesis declines and structural regression when apoptosis is induced. Previous studies suggest this process occurs by the production of luteolytic factors, such as tumour necrosis factor-alpha (TNF-alpha. Methods We examined TNF-alpha, TNF-alpha receptors (TNFR1 and 2 and steroidogenic acute regulatory (StAR protein expression during CL regression in albino Wistar rats. CL from Days 16 and 22 of pregnancy and Day 3 post-partum were examined, in addition CL from Day 16 of pregnancy were cultured in vitro to induce apoptosis. mRNA was quantitated by kinetic RT-PCR and protein expression examined by immunohistochemistry and Western blot analyses. Results TNF-alpha mRNA increased on Day 3 post-partum. TNFR were immunolocalized to luteal cells, and an increase in TNFR2 mRNA observed on Day 3 post-partum whilst no change was detected in TNFR1 mRNA relative to Day 16. StAR protein decreased on Day 3 post-partum and following trophic withdrawal but no change was observed following exogenous TNF-alpha treatment. StAR mRNA decreased on Day 3 post-partum; however, it increased following trophic withdrawal and TNF-alpha treatment in vitro. Conclusion These results demonstrate the existence of TNFR1 and TNFR2 in rat CL and suggest the involvement of TNF-alpha in rat CL regression following parturition. Furthermore, decreased StAR expression over the same time points was consistent with the functional regression of the CL.

  18. Elevated interferon gamma expression in the central nervous system of tumour necrosis factor receptor 1-deficient mice with experimental autoimmune encephalomyelitis

    DEFF Research Database (Denmark)

    Wheeler, Rachel D; Zehntner, Simone P; Kelly, Lisa M

    2006-01-01

    Inflammation in the central nervous system (CNS) can be studied in experimental autoimmune encephalomyelitis (EAE). The proinflammatory cytokines interferon-gamma (IFN-gamma) and tumour necrosis factor (TNF) are implicated in EAE pathogenesis. Signals through the type 1 TNF receptor (TNFR1) are r...

  19. Colocalization of endogenous TNF with a functional intracellular splice form of human TNF receptor type 2

    Directory of Open Access Journals (Sweden)

    Schütze Stephan

    2005-07-01

    Full Text Available Abstract Background Tumor necrosis factor (TNF is a pleiotropic cytokine involved in a broad spectrum of inflammatory and immune responses including proliferation, differentiation, and cell death. The biological effects of TNF are mediated via two cell surface TNF receptors: p55TNFR (TNFR1; CD120a and p75TNFR (TNFR2; CD120b. Soluble forms of these two receptors consisting of the extracellular domains are proteolytically cleaved from the membrane and act as inhibitors. A novel p75TNFR isoform generated by the use of an additional transcriptional start site has been described and was termed hicp75TNFR. We focused on the characterization of this new isoform as this protein may be involved in chronic inflammatory processes. Methods Cell lines were retroviraly transduced with hp75TNFR isoforms. Subcellular localization and colocalization studies with TNF were performed using fluorescence microscopy including exhaustive photon reassignment software, flow cytometry, and receptosome isolation by magnetic means. Biochemical properties of the hicp75TNFR were determined by affinity chromatography, ELISA, and western blot techniques. Results We describe the localization and activation of a differentially spliced and mainly intracellularly expressed isoform of human p75TNFR, termed hicp75TNFR. Expression studies with hicp75TNFR cDNA in different cell types showed the resulting protein mostly retained in the trans-Golgi network and in endosomes and colocalizes with endogenous TNF. Surface expressed hicp75TNFR behaves like hp75TNFR demonstrating susceptibility for TACE-induced shedding and NFκB activation after TNF binding. Conclusion Our data demonstrate that intracellular hicp75TNFR is not accessible for exogenously provided TNF but colocalizes with endogenously produced TNF. These findings suggest a possible intracellular activation mechanism of hicp75TNFR by endogenous TNF. Subsequent NFκB activation might induce anti-apoptotic mechanisms to protect TNF

  20. Diverging mechanisms for TNF-alpha receptors in normal mouse brains and in functional recovery after injury: From gene to behavior.

    Science.gov (United States)

    Quintana, Albert; Molinero, Amalia; Florit, Sergi; Manso, Yasmina; Comes, Gemma; Carrasco, Javier; Giralt, Mercedes; Borup, Rehannah; Nielsen, Finn Cilius; Campbell, Iain L; Penkowa, Milena; Hidalgo, Juan

    2007-09-01

    Cytokines, such as tumour necrosis factor (TNF)-alpha and lymphotoxin-alpha, have been described widely to play important roles in the brain in physiologic conditions and after traumatic injury. However, the exact mechanisms involved in their function have not been fully elucidated. We give some insight on their role by using animals lacking either Type 1 receptor (TNFR1KO) or Type 2 (TNFR2KO) and their controls (C57Bl/6). Both TNFR1KO and to a greater extent TNFR2KO mice showed increased exploration/activity neurobehavioral traits in the hole board test, such as rearings, head dippings, and ambulations, compared with wild-type mice, suggesting an inhibitory role of TNFR1/TNFR2 signaling. In contrast, no significant differences were observed in the elevated plus maze test, ruling out a major role of these receptors in the control of anxiety. We next evaluated the response to a freeze injury to the somatosensorial cortex. The effect of the cryolesion on motor function was evaluated with the horizontal ladder beam test, and the results showed that both TNFR1KO and TNFR2KO mice made fewer errors, suggesting a detrimental role for TNFR1/TNFR2 signaling for coping with brain damage. Expression of approximately 22600 genes was analyzed using an Affymetrix chip (MOE430A) at 0 (unlesioned), 1, or 4 days post-lesion in the three strains. The results show a unique and major role of both TNF receptors on the pattern of gene expression elicited by the injury but also in normal conditions, and suggest that blocking of TNFR1/TNFR2 receptors may be beneficial after a traumatic brain injury.

  1. A chemokine-binding domain in the tumor necrosis factor receptor from variola (smallpox) virus.

    Science.gov (United States)

    Alejo, Alí; Ruiz-Argüello, M Begoña; Ho, Yin; Smith, Vincent P; Saraiva, Margarida; Alcami, Antonio

    2006-04-11

    Variola virus (VaV) is the causative agent of smallpox, one of the most devastating diseases encountered by man, that was eradicated in 1980. The deliberate release of VaV would have catastrophic consequences on global public health. However, the mechanisms that contribute to smallpox pathogenesis are poorly understood at the molecular level. The ability of viruses to evade the host defense mechanisms is an important determinant of viral pathogenesis. Here we show that the tumor necrosis factor receptor (TNFR) homologue CrmB encoded by VaV functions not only as a soluble decoy TNFR but also as a highly specific binding protein for several chemokines that mediate recruitment of immune cells to mucosal surfaces and the skin, sites of virus entry and viral replication at late stages of smallpox. CrmB binds chemokines through its C-terminal domain, which is unrelated to TNFRs, was named smallpox virus-encoded chemokine receptor (SECRET) domain and uncovers a family of poxvirus chemokine inhibitors. An active SECRET domain was found in another viral TNFR (CrmD) and three secreted proteins encoded by orthopoxviruses. These findings identify a previously undescribed chemokine-binding and inhibitory domain unrelated to host chemokine receptors and a mechanism of immune modulation in VaV that may influence smallpox pathogenesis.

  2. Circulating Tumor Necrosis Factor α Receptors Predict the Outcomes of Human IgA Nephropathy: A Prospective Cohort Study.

    Directory of Open Access Journals (Sweden)

    Yun Jung Oh

    Full Text Available The circulating tumor necrosis factor receptors (TNFRs could predict the long-term renal outcome in diabetes, but the role of circulating TNFRs in other chronic kidney disease has not been reported. Here, we investigated the correlation between circulating TNFRs and renal histologic findings on kidney biopsy in IgA nephropathy (IgAN and assessed the notion that the circulating TNFRs could predict the clinical outcome. 347 consecutive biopsy-proven IgAN patients between 2006 and 2012 were prospectively enrolled. Concentrations of circulating TNFRs were measured using serum samples stored at the time of biopsy. The primary clinical endpoint was the decline of estimated glomerular filtration rate (eGFR; ≥ 30% decline compared to baseline. Mean eGFR decreased and proteinuria worsened proportionally as circulating TNFR1 and TNFR2 increased (P < 0.001. Tubulointerstitial lesions such as interstitial fibrosis and tubular atrophy were significantly more severe as concentrations of circulating TNFRs increased, regardless of eGFR levels. The risks of reaching the primary endpoint were significantly higher in the highest quartile of TNFRs compared with other quartiles by the Cox proportional hazards model (TNFR1; hazard ratio 7.48, P < 0.001, TNFR2; hazard ratio 2.51, P = 0.021. In stratified analysis according to initial renal function classified by the eGFR levels of 60 mL/min/1.73 m2, TNFR1 and TNFR2 were significant predictors of renal progression in both subgroups. In conclusion, circulating TNFRs reflect the histology and clinical severity of IgAN. Moreover, elevated concentrations of circulating TNFRs at baseline are early biomarkers for subsequent renal progression in IgAN patients.

  3. Comparison of drug and cell-based delivery: engineered adult mesenchymal stem cells expressing soluble tumor necrosis factor receptor II prevent arthritis in mouse and rat animal models.

    Science.gov (United States)

    Liu, Linda N; Wang, Gang; Hendricks, Kyle; Lee, Keunmyoung; Bohnlein, Ernst; Junker, Uwe; Mosca, Joseph D

    2013-05-01

    Rheumatoid arthritis (RA) is a systemic autoimmune disease with unknown etiology where tumor necrosis factor-α (TNFα) plays a critical role. Etanercept, a recombinant fusion protein of human soluble tumor necrosis factor receptor II (hsTNFR) linked to the Fc portion of human IgG1, is used to treat RA based on the rationale that sTNFR binds TNFα and blocks TNFα-mediated inflammation. We compared hsTNFR protein delivery from genetically engineered human mesenchymal stem cells (hMSCs) with etanercept. Blocking TNFα-dependent intercellular adhesion molecule-1 expression on transduced hMSCs and inhibition of nitric oxide production from TNFα-treated bovine chondrocytes by conditioned culture media from transduced hMSCs demonstrated the functionality of the hsTNFR construction. Implanted hsTNFR-transduced mesenchymal stem cells (MSCs) reduced mouse serum circulating TNFα generated from either implanted TNFα-expressing cells or lipopolysaccharide induction more effectively than etanercept (TNFα, 100%; interleukin [IL]-1α, 90%; and IL-6, 60% within 6 hours), suggesting faster clearance of the soluble tumor necrosis factor receptor (sTNFR)-TNFα complex from the animals. In vivo efficacy of sTNFR-transduced MSCs was illustrated in two (immune-deficient and immune-competent) arthritic rodent models. In the antibody-induced arthritis BalbC/SCID mouse model, intramuscular injection of hsTNFR-transduced hMSCs reduced joint inflammation by 90% compared with untransduced hMSCs; in the collagen-induced arthritis Fischer rat model, both sTNFR-transduced rat MSCs and etanercept inhibited joint inflammation by 30%. In vitro chondrogenesis assays showed the ability of TNFα and IL1α, but not interferon γ, to inhibit hMSC differentiation to chondrocytes, illustrating an additional negative role for inflammatory cytokines in joint repair. The data support the utility of hMSCs as therapeutic gene delivery vehicles and their potential to be used in alleviating inflammation

  4. The Epstein-Barr virus BZLF1 protein inhibits tumor necrosis factor receptor 1 expression through effects on cellular C/EBP proteins.

    Science.gov (United States)

    Bristol, Jillian A; Robinson, Amanda R; Barlow, Elizabeth A; Kenney, Shannon C

    2010-12-01

    The Epstein-Barr virus immediate-early protein, BZLF1 (Z), initiates the switch between latent and lytic infection and plays an essential role in mediating viral replication. Z also inhibits expression of the major receptor for tumor necrosis factor (TNF), TNFR1, thus repressing TNF cytokine signaling, but the mechanism for this effect is unknown. Here, we demonstrate that Z prevents both C/EBPα- and C/EBPβ-mediated activation of the TNFR1 promoter (TNFR1p) by interacting directly with both C/EBP family members. We show that Z interacts directly with C/EBPα and C/EBPβ in vivo and that a Z mutant altered at alanine residue 204 in the bZIP domain is impaired for the ability to interact with both C/EBP proteins. Furthermore, we find that the Z(A204D) mutant is attenuated in the ability to inhibit the TNFR1p but mediates lytic viral reactivation and replication in vitro in 293 cells as well as wild-type Z. Although Z does not bind directly to the TNFR1p in EMSA studies, chromatin immunoprecipitation studies indicate that Z is complexed with this promoter in vivo. The Z(A204D) mutant has reduced interaction with the TNFR1p in vivo but is similar to wild-type Z in its ability to complex with the IL-8 promoter. Finally, we show that the effect of Z on C/EBPα- and C/EBPβ-mediated activation is promoter dependent. These results indicate that Z modulates the effects of C/EBPα and C/EBPβ in a promoter-specific manner and that in some cases (including that of the TNFR1p), Z inhibits C/EBPα- and C/EBPβ-mediated activation.

  5. The TNF receptor 1: a split personality complex.

    Science.gov (United States)

    Barnhart, Bryan C; Peter, Marcus E

    2003-07-25

    The tumor necrosis factor receptor 1 (TNFR1), a prototypic member of the death receptor family signals both cell survival and apoptosis. In this issue of Cell, report that apoptotic TNFR1 signaling proceeds via the sequential formation of two distinct complexes. Since the first complex can activate survival signals and influence the activity of the second complex, this mechanism provides a checkpoint to control the execution of apoptosis.

  6. The Role of IL-6, 8, and 10, sTNFr, CRP, and Pancreatic Elastase in the Prediction of Systemic Complications in Patients with Acute Pancreatitis

    Directory of Open Access Journals (Sweden)

    E. Fisic

    2013-01-01

    Full Text Available Background and Aim. Early assessment of severity in acute pancreatitis (AP is a key measure to provide rational and effective management. The aim of our study is to determine the prognostic value of interleukins (IL 6, 8, and 10, soluble receptor for tumor necrosis factor (sTNFr, pancreatic elastase (E1, and C-reactive protein (CRP as predictors of systemic complications in AP. Patients and Methods. A hundred and fifty patients with confirmed AP were enrolled in the study. The severity of AP was defined according to Atlanta criteria. Measurements of interleukins and sTNFr were performed on the first day of admission. CRP and E1 levels were assessed on admission and after 48 hours. ROC analysis was performed for all parameters. Results. Interleukins and sTNFr significantly differentiated patients with systemic complications from those without. Elevation of IL-6 showed the highest significance as a predictor (. CRP and elastase levels did not differ between mild and severe cases on admission, but reached statistical significance when measured on the third day ( and , resp.. Conclusion. Our study confirmed that IL-6, IL-8, IL-10, and sTNFr measured on admission, and CRP and pancreatic elastase measured on third day of admission represent valuable prognostic factors of severity and systemic complications of AP.

  7. The Role of IL-6, 8, and 10, sTNFr, CRP, and Pancreatic Elastase in the Prediction of Systemic Complications in Patients with Acute Pancreatitis.

    Science.gov (United States)

    Fisic, E; Poropat, G; Bilic-Zulle, L; Licul, V; Milic, S; Stimac, D

    2013-01-01

    Background and Aim. Early assessment of severity in acute pancreatitis (AP) is a key measure to provide rational and effective management. The aim of our study is to determine the prognostic value of interleukins (IL) 6, 8, and 10, soluble receptor for tumor necrosis factor (sTNFr), pancreatic elastase (E1), and C-reactive protein (CRP) as predictors of systemic complications in AP. Patients and Methods. A hundred and fifty patients with confirmed AP were enrolled in the study. The severity of AP was defined according to Atlanta criteria. Measurements of interleukins and sTNFr were performed on the first day of admission. CRP and E1 levels were assessed on admission and after 48 hours. ROC analysis was performed for all parameters. Results. Interleukins and sTNFr significantly differentiated patients with systemic complications from those without. Elevation of IL-6 showed the highest significance as a predictor (P = 0.001). CRP and elastase levels did not differ between mild and severe cases on admission, but reached statistical significance when measured on the third day (P = 0.002 and P = 0.001, resp.). Conclusion. Our study confirmed that IL-6, IL-8, IL-10, and sTNFr measured on admission, and CRP and pancreatic elastase measured on third day of admission represent valuable prognostic factors of severity and systemic complications of AP.

  8. Tumor necrosis factor α sensitizes spinal cord TRPV1 receptors to the endogenous agonist N-oleoyldopamine

    OpenAIRE

    2010-01-01

    Abstract Modulation of synaptic transmission in the spinal cord dorsal horn is thought to be involved in the development and maintenance of different pathological pain states. The proinflamatory cytokine, tumor necrosis factor α (TNFα), is an established pain modulator in both the peripheral and the central nervous system. Up-regulation of TNFα and its receptors (TNFR) in dorsal root ganglion (DRG) cells and in the spinal cord has been shown to play an important role in neuropathic and inflam...

  9. Staphylococcus aureus protein A binding to osteoblast tumour necrosis factor receptor 1 results in activation of nuclear factor kappa B and release of interleukin-6 in bone infection.

    Science.gov (United States)

    Claro, Tânia; Widaa, Amro; McDonnell, Cormac; Foster, Timothy J; O'Brien, Fergal J; Kerrigan, Steven W

    2013-01-01

    Staphylococcus aureus is the major pathogen among the staphylococci and the most common cause of bone infections. These infections are mainly characterized by bone destruction and inflammation, and are often debilitating and very difficult to treat. Previously we demonstrated that S. aureus protein A (SpA) can bind to osteoblasts, which results in inhibition of osteoblast proliferation and mineralization, apoptosis, and activation of osteoclasts. In this study we used small interfering RNA (siRNA) to demonstrate that osteoblast tumour necrosis factor receptor-1 (TNFR-1) is responsible for the recognition of and binding to SpA. TNFR-1 binding to SpA results in the activation of nuclear factor kappa B (NFκB). In turn, NFκB translocates to the nucleus of the osteoblast, which leads to release of interleukin 6 (IL-6). Silencing TNFR-1 in osteoblasts or disruption of the spa gene in S. aureus prevented both NFκB activation and IL-6 release. As well as playing a key role in proinflammatory reactions, IL-6 is also an important osteotropic factor. Release of IL-6 from osteoblasts results in the activation of the bone-resorbing cells, the osteoclasts. Consistent with our results described above, both silencing TNFR-1 in osteoblasts and disruption of spa in S. aureus prevented osteoclast activation. These studies are the first to demonstrate the importance of the TNFR-1-SpA interaction in bone infection, and may help explain the mechanism through which osteoclasts become overactivated, leading to bone destruction. Anti-inflammatory drug therapy could be used either alone or in conjunction with antibiotics to treat osteomyelitis or for prophylaxis in high-risk patients.

  10. TNF receptor signaling inhibits cardiomyogenic differentiation of cardiac stem cells and promotes a neuroadrenergic-like fate.

    Science.gov (United States)

    Hamid, Tariq; Xu, Yuanyuan; Ismahil, Mohamed Ameen; Li, Qianhong; Jones, Steven P; Bhatnagar, Aruni; Bolli, Roberto; Prabhu, Sumanth D

    2016-11-01

    Despite expansion of resident cardiac stem cells (CSCs; c-kit(+)Lin(-)) after myocardial infarction, endogenous repair processes are insufficient to prevent adverse cardiac remodeling and heart failure (HF). This suggests that the microenvironment in post-ischemic and failing hearts compromises CSC regenerative potential. Inflammatory cytokines, such as tumor necrosis factor-α (TNF), are increased after infarction and in HF; whether they modulate CSC function is unknown. As the effects of TNF are specific to its two receptors (TNFRs), we tested the hypothesis that TNF differentially modulates CSC function in a TNFR-specific manner. CSCs were isolated from wild-type (WT), TNFR1-/-, and TNFR2-/- adult mouse hearts, expanded and evaluated for cell competence and differentiation in vitro in the absence and presence of TNF. Our results indicate that TNF signaling in murine CSCs is constitutively related primarily to TNFR1, with TNFR2 inducible after stress. TNFR1 signaling modestly diminished CSC proliferation, but, along with TNFR2, augmented CSC resistance to oxidant stress. Deficiency of either TNFR1 or TNFR2 did not impact CSC telomerase activity. Importantly, TNF, primarily via TNFR1, inhibited cardiomyogenic commitment during CSC differentiation, and instead promoted smooth muscle and endothelial fates. Moreover, TNF, via both TNFR1 and TNFR2, channeled an alternate CSC neuroadrenergic-like fate (capable of catecholamine synthesis) during differentiation. Our results suggest that elevated TNF in the heart restrains cardiomyocyte differentiation of resident CSCs and may enhance adrenergic activation, both effects that would reduce the effectiveness of endogenous cardiac repair and the response to exogenous stem cell therapy, while promoting adverse cardiac remodeling.

  11. Molecular Mechanisms of TNFR-associated Factor 6 (TRAF6) Utilization by the Oncogenic Viral Mimic of CD40, Latent Membrane Protein 1 (LMP1)*

    Science.gov (United States)

    Arcipowski, Kelly M.; Stunz, Laura L.; Graham, John P.; Kraus, Zachary J.; Bush, Tony J. Vanden; Bishop, Gail A.

    2011-01-01

    Latent membrane protein 1 (LMP1), encoded by Epstein-Barr virus, is required for EBV-mediated B cell transformation and plays a significant role in the development of posttransplant B cell lymphomas. LMP1 has also been implicated in exacerbation of autoimmune diseases such as systemic lupus erythematosus. LMP1 is a constitutively active functional mimic of the tumor necrosis factor receptor superfamily member CD40, utilizing tumor necrosis factor receptor-associated factor (TRAF) adaptor proteins to induce signaling. However, LMP1-mediated B cell activation is amplified and sustained compared with CD40. We have previously shown that LMP1 and CD40 use TRAFs 1, 2, 3, and 5 differently. TRAF6 is important for CD40 signaling, but the role of TRAF6 in LMP1 signaling in B cells is not clear. Although TRAF6 binds directly to CD40, TRAF6 interaction with LMP1 in B cells has not been characterized. Here we tested the hypothesis that TRAF6 is a critical regulator of LMP1 signaling in B cells, either as part of a receptor-associated complex and/or as a cytoplasmic adaptor protein. Using TRAF6-deficient B cells, we determined that TRAF6 was critical for LMP1-mediated B cell activation. Although CD40-mediated TRAF6-dependent signaling does not require the TRAF6 receptor-binding domain, we found that LMP1 signaling required the presence of this domain. Furthermore, TRAF6 was recruited to the LMP1 signaling complex via the TRAF1/2/3/5 binding site within the cytoplasmic domain of LMP1. PMID:21262968

  12. High expression of CD40 on B-cell precursor acute lymphoblastic leukemia blasts is an independent risk factor associated with improved survival and enhanced capacity to up-regulate the death receptor CD95

    NARCIS (Netherlands)

    A. Troeger (Anja); L. Glouchkova (Ludmila); B. Ackermann (Birgit); G. Escherich (Gabriele); R. Meisel (Roland); H. Hanenberg (Helmut); M.L. den Boer (Monique); R. Pieters (Rob); G.E. Janka-Schaub (Gritta); U. Goebel (Ulrich); H.J. Laws; D. Dilloo (Dagmar)

    2008-01-01

    textabstractCD40 and CD27, members of the tumor necrosis factor receptor (TNFR) family, are critical regulators of lymphocyte growth and differentiation. In B-cell precursor acute lymphoblastic leukemia (BCP-ALL), we prospectively assessed the impact of CD40 and CD27 on outcome in 121 children treat

  13. TTRAP, a novel protein that associates with CD40, tumor necrosis factor (TNF) receptor-75 and TNF receptor-associated factors (TRAFs), and that inhibits nuclear factor-kappa B activation.

    Science.gov (United States)

    Pype, S; Declercq, W; Ibrahimi, A; Michiels, C; Van Rietschoten, J G; Dewulf, N; de Boer, M; Vandenabeele, P; Huylebroeck, D; Remacle, J E

    2000-06-16

    CD40 belongs to the tumor necrosis factor (TNF) receptor family. CD40 signaling involves the recruitment of TNF receptor-associated factors (TRAFs) to its cytoplasmic domain. We have identified a novel intracellular CD40-binding protein termed TRAF and TNF receptor-associated protein (TTRAP) that also interacts with TNF-R75 and CD30. The region of the CD40 cytoplasmic domain that is required for TTRAP association overlaps with the TRAF6 recognition motif. Association of TTRAP with CD40 increases profoundly in response to treatment of cells with CD40L. Interestingly, TTRAP also associates with TRAFs, with the highest affinity for TRAF6. In transfected cells, TTRAP inhibits in a dose-dependent manner the transcriptional activation of a nuclear factor-kappaB (NF-kappaB)-dependent reporter mediated by CD40, TNF-R75 or Phorbol 12-myristate 13-acetate (PMA) and to a lesser extent by TRAF2, TRAF6, TNF-alpha, or interleukin-1beta (IL-1beta). TTRAP does not affect stimulation of NF-kappaB induced by overexpression of the NF-kappaB-inducing kinase (NIK), the IkappaB kinase alpha (IKKalpha), or the NF-kappaB subunit P65/RelA, suggesting it acts upstream of the latter proteins. Our results indicate that we have isolated a novel regulatory factor that is involved in signal transduction by distinct members of the TNF receptor family.

  14. TNFR2 maintains adequate IL-12 production by dendritic cells in inflammatory responses by regulating endogenous TNF levels.

    Science.gov (United States)

    Martin, Elisabeth M; Remke, Annika; Pfeifer, Eva; Polz, Johannes; Pietryga-Krieger, Anne; Steffens-Weber, Dorothea; Freudenberg, Marina A; Mostböck, Sven; Männel, Daniela N

    2014-10-01

    Sepsis-induced immune reactions are reduced in TNF receptor 2 (TNFR2)-deficient mice as previously shown. In order to elucidate the underlying mechanisms, the functional integrity of myeloid cells of TNFR2-deficient mice was analyzed and compared to wild type (WT) mice. The capacity of dendritic cells to produce IL-12 was strongly impaired in TNF-deficient mice, mirroring impaired production of IL-12 by WT dendritic cells in sepsis or after LPS or TNF pre-treatment. In addition, TNFR2-deficient mice were refractory to LPS pre-treatment and also to hyper-sensitization by inactivated Propionibacterium acnes, indicating habituation to inflammatory stimuli by the immune response when TNFR2 is lacking. Constitutive expression of TNF mRNA in kidney, liver, spleen, colon and lung tissue, and the presence of soluble TNFR2 in urine of healthy WT mice supported the conclusion that TNF is continuously present in naïve mice and controlled by soluble TNFR2. In TNFR2-deficient mice endogenous TNF levels cannot be balanced and the continuous exposure to enhanced TNF levels impairs dendritic cell function. In conclusion, TNF pre-exposure suppresses secondary inflammatory reactions of myeloid cells; therefore, continuous control of endogenous TNF by soluble TNFR2 seems to be essential for the maintenance of adequate sensitivity to inflammatory stimuli.

  15. Initiation of liver growth by tumor necrosis factor: Deficient liver regeneration in mice lacking type I tumor necrosis factor receptor

    OpenAIRE

    Yamada, Yasuhiro; Kirillova, Irina; Peschon, Jacques J.; Fausto, Nelson

    1997-01-01

    The mechanisms that initiate liver regeneration after resection of liver tissue are not known. To determine whether cytokines are involved in the initiation of liver growth, we studied the regeneration of the liver after partial hepatectomy (PH) in mice lacking type I tumor necrosis factor receptor (TNFR-I). DNA synthesis after PH was severely impaired in these animals, and the expected increases in the binding of the NF-κB and STAT3 transcription factors shortly after...

  16. Neutralization of MMP-2 and TNFR1 Regulates the Severity of S. aureus-Induced Septic Arthritis by Differential Alteration of Local and Systemic Proinflammatory Cytokines in Mice.

    Science.gov (United States)

    Sultana, Sahin; Adhikary, Rana; Bishayi, Biswadev

    2017-06-01

    Despite advancement in the field of antibiotics septic arthritis remains a serious concern till date. Staphylococcus aureus is the most common bacterium that causes septic arthritis. Severity of this disease is directly correlated with chronic inflammation induced by proinflammatory cytokines like TNF-α, interleukin (IL)-1β, IL-6, and induction of matrix metalloproteinases (MMPs) including MMP-2. The objective of our study was to evaluate the role of MMP-2 and tumor necrosis factor receptor 1 (TNFR1) in the pathogenesis of S. aureus infection-induced septic arthritis. Mice were infected with live S. aureus (5 × 10(6) cells/ml) followed by administration of MMP-2 inhibitor and TNFR1 antibody. Arthritis index showed highest reduction in severity of arthritis in mice treated with both MMP-2 inhibitor and TNFR1 antibody after infection. Combined neutralization of MMP-2 and TNFR1 led to marked diminution in bacterial count in the combined group. Lowest levels of pro inflammatory cytokines like TNF-α, IL-1β, IL-6, and IFN-γ were observed in both serum and synovial tissues indicating maximum protection in S. aureus arthritis during combination treatment. Increment in the level of IL-10 in the combination group could be positively correlated with the recovery of arthritis. Similarly, expressions of COX-2 and iNOS, markers of acute inflammation were also significantly reduced in the combination group due to resolution of inflammation. Levels of O2(.-) and NO also showed a significant fall in case of the group treated with MMP-2 inhibitor and TNFR1 antibody both. Neutralization of both MMP-2 and TNFR1 caused rapid decline in recruitment of neutrophil and macrophages in the synovial tissues as evident from reduced MPO and MCP-1 levels, respectively, compared to other groups. Overall, it can be suggested that administration of MMP-2 inhibitor and TNFR1 antibody in combination is protective against the severity of inflammation and cartilage destruction associated with S

  17. Cytoplasmic truncation of the p55 tumour necrosis factor (TNF) receptor abolishes signalling, but not induced shedding of the receptor

    DEFF Research Database (Denmark)

    Brakebusch, C; Nophar, Y; Kemper, O;

    1992-01-01

    The mechanistic relationship between the signalling for the TNF effects by the human p55 TNF receptor (hu-p55-TNF-R) and the formation of a soluble form of the receptor, which is inhibitory to these effects, was explored by examining the function of C-terminally truncated mutants of the receptor,...

  18. Circulating TNF Receptors 1 and 2 Predict Mortality in Patients with End-stage Renal Disease Undergoing Dialysis

    Science.gov (United States)

    Gohda, Tomohito; Maruyama, Shuntaro; Kamei, Nozomu; Yamaguchi, Saori; Shibata, Terumi; Murakoshi, Maki; Horikoshi, Satoshi; Tomino, Yasuhiko; Ohsawa, Isao; Gotoh, Hiromichi; Nojiri, Shuko; Suzuki, Yusuke

    2017-01-01

    Relatively high circulating levels of soluble tumor necrosis factor (TNF) receptors (TNFRs: TNFR1, TNFR2) have been associated with not only progression to end-stage renal disease but also mortality in patients with diabetes. It remains unknown whether elevated TNFR levels in haemodialysis patients are associated with mortality. We studied 319 patients receiving maintenance haemodialysis who were followed for a median of 53 months. Circulating markers of TNF pathway (TNFα and TNFRs) were measured with immunoassay. Strong positive correlations between TNFR1 and TNFR2 were observed (r = 0.81, P risk of cardiovascular and/or all-cause mortality independent of all relevant covariates in patients undergoing haemodialysis. PMID:28256549

  19. Generation and characterization of small single domain antibodies inhibiting human tumor necrosis factor receptor 1.

    Science.gov (United States)

    Steeland, Sophie; Puimège, Leen; Vandenbroucke, Roosmarijn E; Van Hauwermeiren, Filip; Haustraete, Jurgen; Devoogdt, Nick; Hulpiau, Paco; Leroux-Roels, Geert; Laukens, Debby; Meuleman, Philip; De Vos, Martine; Libert, Claude

    2015-02-13

    The cytokine TNF is a well known drug target for several inflammatory diseases such as Crohn disease. Despite the great success of TNF blockers, therapy could be improved because of high costs and side effects. Selective inhibition of TNF receptor (TNFR) 1 signaling holds the potential to greatly reduce the pro-inflammatory activity of TNF, thereby preserving the advantageous immunomodulatory signals mediated by TNFR2. We generated a selective human TNFR1 inhibitor based on Nanobody (Nb) technology. Two anti-human TNFR1 Nbs were linked with an anti-albumin Nb to generate Nb Alb-70-96 named "TNF Receptor-One Silencer" (TROS). TROS selectively binds and inhibits TNF/TNFR1 and lymphotoxin-α/TNFR1 signaling with good affinity and IC50 values, both of which are in the nanomolar range. Surface plasmon resonance analysis reveals that TROS competes with TNF for binding to human TNFR1. In HEK293T cells, TROS strongly reduces TNF-induced gene expression, like IL8 and TNF, in a dose-dependent manner; and in ex vivo cultured colon biopsies of CD patients, TROS inhibits inflammation. Finally, in liver chimeric humanized mice, TROS antagonizes inflammation in a model of acute TNF-induced liver inflammation, reflected in reduced human IL8 expression in liver and reduced IL6 levels in serum. These results demonstrate the considerable potential of TROS and justify the evaluation of TROS in relevant disease animal models of both acute and chronic inflammation and eventually in patients.

  20. Tumor necrosis factor (TNF) receptor-associated factor (TRAF)-interacting protein (TRIP) negatively regulates the TRAF2 ubiquitin-dependent pathway by suppressing the TRAF2-sphingosine 1-phosphate (S1P) interaction.

    Science.gov (United States)

    Park, Eui-Soon; Choi, Seunga; Shin, Bongjin; Yu, Jungeun; Yu, Jiyeon; Hwang, Jung-Me; Yun, Hyeongseok; Chung, Young-Ho; Choi, Jong-Soon; Choi, Yongwon; Rho, Jaerang

    2015-04-10

    The signaling pathway downstream of TNF receptor (TNFR) is involved in the induction of a wide range of cellular processes, including cell proliferation, activation, differentiation, and apoptosis. TNFR-associated factor 2 (TRAF2) is a key adaptor molecule in TNFR signaling complexes that promotes downstream signaling cascades, such as nuclear factor-κB (NF-κB) and mitogen-activated protein kinase activation. TRAF-interacting protein (TRIP) is a known cellular binding partner of TRAF2 and inhibits TNF-induced NF-κB activation. Recent findings that TRIP plays a multifunctional role in antiviral response, cell proliferation, apoptosis, and embryonic development have increased our interest in exploring how TRIP can affect the TNFR-signaling pathway on a molecular level. In our current study, we demonstrated that TRIP is negatively involved in the TNF-induced inflammatory response through the down-regulation of proinflammatory cytokine production. Here, we demonstrated that the TRAF2-TRIP interaction inhibits Lys(63)-linked TRAF2 ubiquitination by inhibiting TRAF2 E3 ubiquitin (Ub) ligase activity. The TRAF2-TRIP interaction inhibited the binding of sphingosine 1-phosphate, which is a cofactor of TRAF2 E3 Ub ligase, to the TRAF2 RING domain. Finally, we demonstrated that TRIP functions as a negative regulator of proinflammatory cytokine production by inhibiting TNF-induced NF-κB activation. These results indicate that TRIP is an important cellular regulator of the TNF-induced inflammatory response.

  1. IGFBP-3 inhibits TNF-α production and TNFR-2 signaling to protect against retinal endothelial cell apoptosis.

    Science.gov (United States)

    Zhang, Qiuhua; Steinle, Jena J

    2014-09-01

    In models of diabetic retinopathy, insulin-like growth factor binding protein-3 (IGFBP-3) protects against tumor necrosis factors-alpha (TNF-α)-mediated apoptosis of retinal microvascular endothelial cells (REC), but the underlying mechanisms are unclear. Our current findings suggest that at least two discrete but complimentary pathways contribute to the protective effects of IGFBP-3; 1) IGFBP-3 directly activates the c-Jun kinase/tissue inhibitor of metalloproteinase-3/TNF-α converting enzyme (c-Jun/TIMP-3/TACE), pathway, which in turn inhibits TNF-α production; 2) IGFBP-3 acts through the IGFBP-3 receptor, low-density lipoprotein receptor-related protein 1 (LRP1), to inhibit signaling of TNF-α receptor 2 (TNFR2). Combined, these two IGFBP-3 pathways substantially reduce REC apoptosis and offer potential targets for the treatment of diabetic retinopathy.

  2. Direct bone formation during distraction osteogenesis does not require TNF alpha receptors and elevated serum TNF alpha fails to inhibit bone formation in TNFR1 deficient mice

    Science.gov (United States)

    Distraction osteogenesis (DO) is a process which induces direct new bone formation as a result of mechanical distraction. Tumor necrosis factor-alpha (TNF) is a cytokine that can modulate osteoblastogenesis. The direct effects of TNF on direct bone formation in rodents are hypothetically mediated th...

  3. Molecular characterization and expression analysis of the first Porifera tumor necrosis factor superfamily member and of its putative receptor in the marine sponge Chondrosia reniformis.

    Science.gov (United States)

    Pozzolini, Marina; Scarfì, Sonia; Ghignone, Stefano; Mussino, Francesca; Vezzulli, Luigi; Cerrano, Carlo; Giovine, Marco

    2016-04-01

    Here we report the molecular cloning and characterization of the first Tumor Necrosis Factor homologous and of its putative receptor in the marine sponge Chondrosia reniformis: chTNF and chTNFR, respectively. The deduced chTNF amino acid sequence is a type II transmembrane protein containing the typical TNFSF domain. Phylogenetic analysis reveals that chTNF is more related to Chordata TNFs rather than to other invertebrates. chTNF and chTNFR are constitutively expressed both in the ectosome and in the choanosome of the sponge, with higher levels in the ectosome. chTNF and chTNFR mRNAs were monitored in sponge fragmorphs treated with Gram(+) or Gram(-) bacteria. chTNF was significantly upregulated in Gram(+)-treated fragmorphs as compared to controls, while chTNFR was upregulated by both treatments. Finally, the possible chTNF fibrogenic role in sponge fragmorphs was studied by TNF inhibitor treatment measuring fibrillar and non fibrillar collagen gene expression; results indicate that the cytokine is involved in sponge collagen deposition and homeostasis.

  4. TNFR2基因的CA重复多态性在两个独立的白人群体中与肥胖表型的连锁和关联%Linkage and Association Between CA Repeat Polymorphism of the TNFR2 Gene and Obesity Phenotypes in Two Independent Caucasian Populations

    Institute of Scientific and Technical Information of China (English)

    黄青阳; SHEN Hui; DENG Hong-Yi; Theresa Conway; Leo Elze; K.Michael Davies; Roberr R.Recker; 邓红文

    2006-01-01

    我们先前通过全基因组扫描发现1p36与体重指数显提示性连锁(LOD=2.09).肿瘤坏死因子受体2(TNFR2)定位于1p36,是肥胖的一个极好的图位和功能侯选基因.本研究采用数量传递连锁不平衡检验在两个大的独立的白人样本中进行了TNFR2基因与肥胖表型的连锁与关联检验.第一组受试者由来自79个多代家系的1 836个个体组成;第二组受试者由来自157个核心家庭的636个个体组成.所检测的肥胖表型包括体重指数、脂肪量和脂肪量百分数.在多代家系中我们发现TNFR2基因变异与BMI显著连锁(P=0.0056).结果表明,TNFR2基因是影响白人BMI变异的一个数量性状位点.%Previously, our group has reported a suggestive linkage evidence of 1p36 with body mass index (BMI) (LOD =2.09).The tumor necrosis factor receptor 2 (TNFR2) at 1p36 is an excellent positional and functional candidate gene for obesity. In this study, we have investigated the linkage and association between the TNFR2 gene and obesity phenotypes in two large independent samples, using the quantitative transmission disequilibrium tests (QTDT). The first group was made up of 1 836 individuals from 79 multi-generation pedigrees. The second group was a randomly ascertained set of 636 individuals from 157 US Caucasian nuclear families. Obesity phenotypes tested include BMI, fat mass, and percentage fat mass (PFM). A significant result (P = 0.0056) was observed for linkage with BMI in the sample of the multigenerational pedigrees. Our data support the TNFR2 gene as a quantitative trait locus (QTL) underlying BMI variation in the Caucasian populations.

  5. Effect of liver regeneration after partial hepatectomy and ischemia-reperfusion on expression of growth factor receptors

    Institute of Scientific and Technical Information of China (English)

    P Baier; G Wolf-Vorbeck; S Hempel; UT Hopt; E von Dobschuetz

    2006-01-01

    AIM: To investigate the effects of experimental partial hepatectomy and normothermic ischemia-reperfusion damage on the time course of the expression of four different growth factor receptors in liver regeneration.This is relevant due to the potential therapeutic use of growth factors in stimulating liver regeneration.METHODS: For partial hepatectomy (PH) 80% of the liver mass was resected in Sprague Dawley rats.Ischemia and reperfusion (I/R) were induced by occlusion of the portal vein and the hepatic artery for 15 min. The epidermal growth factor receptor, hepatic growth factor receptor, fibroblast growth factor receptor and tumour necrosis factor receptor-1 were analysed by immunohistochemistry up to 72 h after injury.Quantitative RT-PCR was performed at the time point of minimal receptor expression (24 h).RESULTS: In immunohistochemistry, EGFR, HGFR,FGFR and TNFR1 showed biphasic kinetics after partial hepatectomy with a peak up to 12 h, a nadir after 24 h and another weak increase up to 72 h. During liver regeneration, after ischemia and reperfusion, the receptor expression was lower; the nadir at 24 h after reperfusion was the same. To evaluate whether this nadir was caused by a lack of mRNA transcription, or due to a posttranslational regulation, RT-PCR was performed at 24 h and compared to resting liver. In every probe there was specific mRNA for the receptors. EGFR, FGFR and TNFR1 mRNA expression was equal or lower than in resting liver, HGFR expression after I/R was stronger than in the control.CONCLUSION: At least partially due to a post-transcriptional process, there is a nadir in the expression of the analysed receptors 24 h after liver injury. Therefore,a therapeutic use of growth factors to stimulate liver regeneration 24 h after the damage might be not successful.

  6. Ginsenoside metabolite compound K exerts joint-protective effect by interfering with synoviocyte function mediated by TNF-α and Tumor necrosis factor receptor type 2.

    Science.gov (United States)

    Wang, Ying; Chen, Jingyu; Luo, Xuexia; Zhang, Ying; Si, Ming; Wu, Huaxun; Yan, Chang; Wei, Wei

    2016-01-15

    Ginsenoside metabolite compound K (CK), metabolite of the ginsenoside, is considered to exert numerous pharmacological efficacies of ginsenoside, including anti-inflammation and immunoregulatory effects. Rheumatoid arthritis (RA) is a multi-systemic autoimmune disease characterized by hyperplastic synovial membrane and systemic inflammation, which ultimately lead to progressive destructive inflammatory arthropathy. To evaluate the potential joint-protective effects of CK and the underlying mechanism, adjuvant arthritis (AA) was induced by complete Freund's adjuvant in rats. After the onset of arthritis, The effect of CK on AA rats was evaluated by histopathology of the joint. The proliferation of fibroblast-like synoviocyte(FLS) was assayed by the Cell Counting Kit-8.The migration of FLS was assayed by transwell migration assay. Cytokines in the supernatant from FLS were measured by ELISA kit. Expression of Tumor Necrosis Factor Receptor Type 1(TNFR1) and Tumor Necrosis Factor Receptor Type 2(TNFR2) were detected by immunostaining analysis and western blot analysis. CK (80mg/kg) significantly ameliorated the histopathological change of joint in AA rats, balanced the RANKL/OPG ratio and attenuated the proliferation and migration of AA-FLS. CK suppressed the secretion of proinflammatory cytokines TNF-α and downregulated the expression of TNFR2 on AA-FLS. In vitro CK also significantly suppressed proliferation, migration and secretion of AA-FLS mediated by TNF-α. Further studies showed that the effects of CK on AA-FLS were reversed by using glucocorticoid receptor (GR) antagonist (mifepristone). Our data suggest that CK exerts joint-protective effect by interfering with synoviocyte function mediated by TNF-α and TNFR2, and this effect may be mediated by GR.

  7. Lack of TNF-alpha receptor type 2 protects motor neurons in a cellular model of amyotrophic lateral sclerosis and in mutant SOD1 mice but does not affect disease progression.

    Science.gov (United States)

    Tortarolo, Massimo; Vallarola, Antonio; Lidonnici, Dario; Battaglia, Elisa; Gensano, Francesco; Spaltro, Gabriella; Fiordaliso, Fabio; Corbelli, Alessandro; Garetto, Stefano; Martini, Elisa; Pasetto, Laura; Kallikourdis, Marinos; Bonetto, Valentina; Bendotti, Caterina

    2015-10-01

    Changes in the homeostasis of tumor necrosis factor α (TNFα) have been demonstrated in patients and experimental models of amyotrophic lateral sclerosis (ALS). However, the contribution of TNFα to the development of ALS is still debated. TNFα is expressed by glia and neurons and acts through the membrane receptors TNFR1 and TNFR2, which may have opposite effects in neurodegeneration. We investigated the role of TNFα and its receptors in the selective motor neuron death in ALS in vitro and in vivo. TNFR2 expressed by astrocytes and neurons, but not TNFR1, was implicated in motor neuron loss in primary SOD1-G93A co-cultures. Deleting TNFR2 from SOD1-G93A mice, there was partial but significant protection of spinal motor neurons, sciatic nerves, and tibialis muscles. However, no improvement of motor impairment or survival was observed. Since the sciatic nerves of SOD1-G93A/TNFR2-/- mice showed high phospho-TAR DNA-binding protein 43 (TDP-43) accumulation and low levels of acetyl-tubulin, two indices of axonal dysfunction, the lack of symptom improvement in these mice might be due to impaired function of rescued motor neurons. These results indicate the interaction between TNFR2 and membrane-bound TNFα as an innovative pathway involved in motor neuron death. Nevertheless, its inhibition is not sufficient to stop disease progression in ALS mice, underlining the complexity of this pathology. We show evidence of the involvement of neuronal and astroglial TNFR2 in the motor neuron degeneration in ALS. Both concur to cause motor neuron death in primary astrocyte/spinal neuron co-cultures. TNFR2 deletion partially protects motor neurons and sciatic nerves in SOD1-G93A mice but does not improve their symptoms and survival. However, TNFR2 could be a new target for multi-intervention therapies.

  8. A synthetic peptide derived from A1 module in CRD4 of human TNF receptor-1 inhibits binding and proinflammatory effect of human TNF-alpha.

    Science.gov (United States)

    Cao, Yingnan; Wang, Zhaohe; Bu, Xianzhang; Tang, Shu; Mei, Zhengrong; Liu, Peiqing

    2009-06-01

    Tumour necrosis factor alpha (TNF-alpha) is a proinflammatory cytokine, which has been shown to be a causative factor in rheumatoid arthritis, inflammatory bowel disease and septic shock. Proinflammatory effect of TNF-alpha is activated mainly through human TNF receptor-1 (TNF-R1). However, the role of the fourth cystein-rich domain (CRD4) of TNF-R1 extracellular portion in the interaction of TNF-alpha with TNF-R1 is still unclear. In the present study, binding activity of TNF-alpha to TNF-R1 and protein levels of IkappaB-alpha and nuclear transcription factor kappa B (NF-kappaB) p65 subunit in HeLa cells were measured using enzyme-linked immunosorbent assay (ELISA) and western-blot analysis. Pep 3 (LRENECVS) which was derived from the hydrophilic region of A1 module in CRD4 remarkably inhibited the binding of TNF-alpha to TNF-R1, and also reversed TNF-alpha-induced degradation of IkappaB-alpha and nuclear translocation of NF-kappaB p65 subunit in HeLa cells. Our results confirmed that the hydrophilic region of A1 module in CRD4 participated in the interaction of TNF-alpha with TNF-R1, and demonstrated the potential of small-molecule TNF-alpha extracellular inhibitors targeting at A1 module in CRD4 of TNF-R1 in suppressing proinflammatory effect of TNF-alpha.

  9. Clinical evaluation of proinflammatory cytokine inhibitors (sTNFR I, sTNFR II, IL-1 ra), anti-inflammatory cytokines (IL-10, IL-13) and activation of neutrophils after burn-induced inflammation.

    Science.gov (United States)

    Sikora, J P; Chlebna-Sokół, D; Andrzejewska, E; Chrul, S; Polakowska, E; Wysocka, A; Sikora, A

    2008-08-01

    The study was aimed at evaluating the involvement of sTNFR I, sTNFR II, IL-1 ra, IL-10, IL-13 and reactive oxygen species (ROS) in systemic inflammatory response syndrome (SIRS) development in severely burned children and at assessing the prognostic value of the immunological markers studied. The study comprised 37 patients (17 burned children and 20 controls). Serum levels of the markers determined by means of ELISA and respiratory burst of neutrophils as well as p55 and p75 tumour necrosis factor-alpha (TNF-alpha) receptor expression using flow cytometry were evaluated twice. The burned children presented significantly higher levels of IL-10 and cytokine inhibitors within the first 6-24 h after injury compared with controls (P burn therapy, whereas ROS generation evidently augmented (P burned children; their monitoring allows for an assessment of the systemic inflammatory reaction activity. The neutrophil BURSTTEST and IL-1 ra might have been clinically helpful markers of SIRS prognosis.

  10. Peptides identify multiple hotspots within the ligand binding domain of the TNF receptor 2

    Directory of Open Access Journals (Sweden)

    Lennick Michael

    2003-01-01

    Full Text Available Abstract Background Hotspots are defined as the minimal functional domains involved in protein:protein interactions and sufficient to induce a biological response. Results Here we describe the use of complex and high diversity phage display libraries to isolate peptides (called Hotspot Ligands or HSPLs which sub-divide the ligand binding domain of the tumor necrosis factor receptor 2 (TNFR2; p75 into multiple hotspots. We have shown that these libraries could generate HSPLs which not only subdivide hotspots on protein and non-protein targets but act as agonists or antagonists. Using this approach, we generated peptides which were specific for human TNFR2, could be competed by the natural ligands, TNFα and TNFβ and induced an unexpected biological response in a TNFR2-specific manner. Conclusions To our knowledge, this is the first report describing the dissection of the TNFR2 into biologically active hotspots with the concomitant identification of a novel and unexpected biological activity.

  11. Progranulin inhibits expression and release of chemokines CXCL9 and CXCL10 in a TNFR1 dependent manner

    Science.gov (United States)

    Mundra, Jyoti Joshi; Jian, Jinlong; Bhagat, Priyal; Liu, Chuan-ju

    2016-01-01

    Progranulin (PGRN), a pleiotrophic growth factor, is known to play an important role in the maintenance and regulation of the homeostatic dynamics of normal tissue development, proliferation, regeneration, and host-defense. PGRN also has potent anti-inflammatory functionality, and deregulated PGRN is associated with rheumatoid arthritis and inflammatory bowel disease. We have previously reported that PGRN directly binds to TNFR and significantly enhances Treg population and stimulatesIL-10 production. To further investigate PGRN’s function in the immune system we performed a gene array analysis on CD4+ T cells from wild type B6 mice and PGRN −/− mice. We identified many chemokines and their receptors, among which CXCL9 and CXCL10 were most prominent, that were significantly induced in PGRN null mice. Administration of recombinant PGRN protein strongly inhibited TNF and IFN-γ-induced CXCL9 and CXCL10 expression. In addition, CXCL9 expression is strongly upregulated in PGRN KO mice and its level is correlated with severity of inflammation in a dermatitis model. Further, we have demonstrated that PGRN-mediated inhibition of chemokine expression largely depends on TNFR1. Taken together, this study provides new insights into the mechanisms underlying PGRN mediated regulation of various inflammatory and autoimmune diseases. PMID:26892362

  12. Defining an EPOR- regulated transcriptome for primary progenitors, including Tnfr-sf13c as a novel mediator of EPO- dependent erythroblast formation.

    Directory of Open Access Journals (Sweden)

    Seema Singh

    Full Text Available Certain concepts concerning EPO/EPOR action modes have been challenged by in vivo studies: Bcl-x levels are elevated in maturing erythroblasts, but not in their progenitors; truncated EPOR alleles that lack a major p85/PI3K recruitment site nonetheless promote polycythemia; and Erk1 disruption unexpectedly bolsters erythropoiesis. To discover novel EPO/EPOR action routes, global transcriptome analyses presently are applied to interrogate EPO/EPOR effects on primary bone marrow-derived CFUe-like progenitors. Overall, 160 EPO/EPOR target transcripts were significantly modulated 2-to 21.8-fold. A unique set of EPO-regulated survival factors included Lyl1, Gas5, Pim3, Pim1, Bim, Trib3 and Serpina 3g. EPO/EPOR-modulated cell cycle mediators included Cdc25a, Btg3, Cyclin-d2, p27-kip1, Cyclin-g2 and CyclinB1-IP-1. EPO regulation of signal transduction factors was also interestingly complex. For example, not only Socs3 plus Socs2 but also Spred2, Spred1 and Eaf1 were EPO-induced as negative-feedback components. Socs2, plus five additional targets, further proved to comprise new EPOR/Jak2/Stat5 response genes (which are important for erythropoiesis during anemia. Among receptors, an atypical TNF-receptor Tnfr-sf13c was up-modulated >5-fold by EPO. Functionally, Tnfr-sf13c ligation proved to both promote proerythroblast survival, and substantially enhance erythroblast formation. The EPOR therefore engages a sophisticated set of transcriptome response circuits, with Tnfr-sf13c deployed as one novel positive regulator of proerythroblast formation.

  13. Defining an EPOR- regulated transcriptome for primary progenitors, including Tnfr-sf13c as a novel mediator of EPO- dependent erythroblast formation.

    Science.gov (United States)

    Singh, Seema; Dev, Arvind; Verma, Rakesh; Pradeep, Anamika; Sathyanarayana, Pradeep; Green, Jennifer M; Narayanan, Aishwarya; Wojchowski, Don M

    2012-01-01

    Certain concepts concerning EPO/EPOR action modes have been challenged by in vivo studies: Bcl-x levels are elevated in maturing erythroblasts, but not in their progenitors; truncated EPOR alleles that lack a major p85/PI3K recruitment site nonetheless promote polycythemia; and Erk1 disruption unexpectedly bolsters erythropoiesis. To discover novel EPO/EPOR action routes, global transcriptome analyses presently are applied to interrogate EPO/EPOR effects on primary bone marrow-derived CFUe-like progenitors. Overall, 160 EPO/EPOR target transcripts were significantly modulated 2-to 21.8-fold. A unique set of EPO-regulated survival factors included Lyl1, Gas5, Pim3, Pim1, Bim, Trib3 and Serpina 3g. EPO/EPOR-modulated cell cycle mediators included Cdc25a, Btg3, Cyclin-d2, p27-kip1, Cyclin-g2 and CyclinB1-IP-1. EPO regulation of signal transduction factors was also interestingly complex. For example, not only Socs3 plus Socs2 but also Spred2, Spred1 and Eaf1 were EPO-induced as negative-feedback components. Socs2, plus five additional targets, further proved to comprise new EPOR/Jak2/Stat5 response genes (which are important for erythropoiesis during anemia). Among receptors, an atypical TNF-receptor Tnfr-sf13c was up-modulated >5-fold by EPO. Functionally, Tnfr-sf13c ligation proved to both promote proerythroblast survival, and substantially enhance erythroblast formation. The EPOR therefore engages a sophisticated set of transcriptome response circuits, with Tnfr-sf13c deployed as one novel positive regulator of proerythroblast formation.

  14. Tumor necrosis factor-alpha inhibits pre-osteoblast differentiation through its type-1 receptor.

    Science.gov (United States)

    Abbas, Sabiha; Zhang, Yan-Hong; Clohisy, John C; Abu-Amer, Yousef

    2003-04-01

    Tumor necrosis factor-alpha (TNF) is a pro-inflammatory cytokine with a profound role in many skeletal diseases. The cytokine has been described as a mediator of bone loss in osteolysis and other inflammatory bone diseases. In addition to its known bone resorptive action, TNF reduces bone formation by inhibiting osteoblast differentiation. Using primary and transformed osteoblastic cells, we first document that TNF inhibits expression of alkaline phosphatase and matrix deposition, both considered markers of osteoblast differentiation. The effects are dose- and time-dependent. Core-binding factor A1 (cbfa1) is a transcription factor critical for osteoblast differentiation, and we show here that it is activated by the osteoblast differentiation agent, beta-glycerophosphate. Therefore, we investigated whether the inhibitory effects of TNF were associated with altered activity of this transcription factor. Using retardation assays, we show that TNF significantly inhibits cbfal activation by beta-glycerophosphate, manifested by reduced DNA-binding activity. Next, we turned to determine the signaling pathway by which TNF inhibits osteoblast differentiation. Utilizing animals lacking individual TNF receptors, we document that TNFr1 is required for transmitting the cytokine's inhibitory effect. In the absence of this receptor, TNF failed to impact all osteoblast differentiation markers tested. In summary, TNF blocks expression of osteoblast differentiation markers and inhibits beta-glycerophosphate-induced activation of the osteoblast differentiation factor cbfa1. Importantly, these effects are mediated via a mechanism requiring the TNF type-1 receptor.

  15. Role of tumour necrosis factor receptor-1 and nuclear factor-κB in production of TNF-α-induced pro-inflammatory microparticles in endothelial cells.

    Science.gov (United States)

    Lee, S K; Yang, S-H; Kwon, I; Lee, O-H; Heo, J H

    2014-09-02

    Tumour necrosis factor-α (TNF-α) is upregulated in many inflammatory diseases and is also a potent agent for microparticle (MP) generation. Here, we describe an essential role of TNF-α in the production of endothelial cell-derived microparticles (EMPs) in vivo and the function of TNF-α-induced EMPs in endothelial cells. We found that TNF-α rapidly increased blood levels of EMPs in mice. Treatment of human umbilical vein endothelial cells (HUVECs) with TNF-α also induced EMP formation in a time-dependent manner. Silencing of TNF receptor (TNFR)-1 or inhibition of the nuclear factor-κB (NF-κB) in HUVECs impaired the production of TNF-α-induced EMP. Incubation of HUVECs with PKH-67-stained EMPs showed that endothelial cells readily engulfed EMPs, and the engulfed TNF-α-induced EMPs promoted the expression of pro-apoptotic molecules and upregulated intercellular adhesion molecule-1 level on the cell surface, which led to monocyte adhesion. Collectively, our findings indicate that the generation of TNF-α-induced EMPs was mediated by TNFR1 or NF-κB and that EMPs can contribute to apoptosis and inflammation of endothelial cells.

  16. Glucocorticoid-Induced TNFR family Related gene (GITR) enhances dendritic cell activity.

    Science.gov (United States)

    Ronchetti, Simona; Nocentini, Giuseppe; Petrillo, Maria Grazia; Bianchini, Rodolfo; Sportoletti, Paolo; Bastianelli, Alessandra; Ayroldi, Emira M; Riccardi, Carlo

    2011-03-30

    Glucocorticoid-Induced TNFR family Related gene (GITR), a Tumor Necrosis Factor Receptor Superfamily (TNFRSF) member involved in immune/inflammatory processes, has been previously shown to regulate T cell activation. To study GITR role in antigen presenting cells, we evaluated the capability of bone marrow derived dendritic cells (BMDC) from GITR(-/-) mice to stimulate the activation of CD4(+)CD25(-) T lymphocytes. We found that GITR(-/-) BMDC are weaker stimulators of T cell proliferation than GITR(+/+) BMDC, either in syngenic or allogenic BMDC/T cell co-cultures. Expression of GITR in GITR(-/-) BMDC restored their ability to activate T cells while GITR silencing in GITR(+/+) BMDC inhibited the capability to stimulate T cells. GITR(-/-) BMDC showed a reduced production of the pro-inflammatory cytokine IL-6 and an increased production of the anti-inflammatory cytokine IL-10. Notably, co-culture of CD4(+)CD25(-) cells with GITR(-/-) BMDC originated FoxP3(+) cells, secreting IL-10 and TGF-β. Finally, in vivo injection of GITR(-/-) OVA-loaded BMDC led to a lower cell number and a lower activated cell number in draining lymph nodes than in GITR(+/+) OVA-loaded BMDC injected mice. Together, these results indicate that GITR plays a role in regulating BMDC activity.

  17. Regulation of the PKCθ-NF-κB Axis in T lymphocytes by the Tumor Necrosis Factor Receptor Family Member OX40

    Directory of Open Access Journals (Sweden)

    Takanori eSo

    2012-05-01

    Full Text Available Antigen primed T lymphocytes need to expand and persist to promote adaptive immunity. The growth and survival signals that control this are in large part provided by the NF-κB pathway in activated or effector/memory T cells. Although several membrane receptors impact NF-κB activation, signaling from OX40 (CD134, TNFRSF4, a member of the tumor necrosis factor receptor (TNFR superfamily, has proven to be important for T cell immunity and a strong contributor to NF-κB activity. PKCθ directs the TCR and CD28-dependent assembly of a CBM complex (CARMA1, BCL10, and MALT1 for efficient activation of NF-κB, raising the question of whether other membrane bound receptors that activate NF-κB also require this PKCθ-CBM axis to control TCR-independent T cell activity. We discuss here our recent data demonstrating that after ligation by OX40L (CD252, TNFSF4 expressed on antigen-presenting cells, OX40 translocates into detergent-insoluble membrane lipid microdomains (DIM or lipid rafts in T cells irrespective of TCR signals, and assembles into a novel signaling complex containing PKCθ, together with TRAF2, RIP1, the CBM complex, and the IKKα/β/γ complex. PKCθ is required for optimal NF-κB activation mediated by OX40 and thus works as an essential component of this OX40 signalosome. We also discuss the likelihood that other TNFR superfamily molecules might complex with PKCθ in T cells, and whether PKC isoforms may be critical to the function of TNFR molecules in general. 

  18. Role of heme oxygenase 1 in TNF/TNF receptor-mediated apoptosis after hepatic ischemia/reperfusion in rats.

    Science.gov (United States)

    Kim, Seok-Joo; Eum, Hyun-Ae; Billiar, Timothy R; Lee, Sun-Mee

    2013-04-01

    Hepatocellular apoptosis commonly occurs in ischemia/reperfusion (I/R) injury. The binding of tumor necrosis factor (TNF) to TNF receptor 1 (TNFR1) leads to the formation of a death-inducing signaling complex (DISC), which subsequently initiates a caspase cascade resulting in apoptosis. Heme oxygenase 1 (HO-1) confers cytoprotection against cell death in I/R injury and inhibits stress-induced apoptotic pathways in vitro. This study investigated the role of HO-1 in modulating TNF/TNFR1-mediated cell death pathways in hepatic I/R injury. Rats were pretreated with hemin, an HO-1 inducer, and zinc protoporphyrin (ZnPP), an HO-1 inhibitor, before undergoing hepatic I/R. Heme oxygenase 1 activity increased after reperfusion. Ischemia/reperfusion-induced hepatocellular apoptosis was attenuated by hemin, as determined by the caspase-3 and -8 activity assays and TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling). Zinc protoporphyrin eliminated the cytoprotective effect of hemin. Hepatic TNFR1 protein expression was unchanged among the experimental groups, whereas mitochondrial TNFR1 protein increased after I/R. Ischemia/reperfusion increased the quantity of DISC components, including TRADD (TNFR1-associated death domain), FADD (Fas-associated death domain), and caspase-8, as well as the assembly of DISCs within the liver. In the mitochondrial fraction, TNFR1-associated caspase-8 was increased after I/R. These increases were attenuated by hemin; zinc protoporphyrin eliminated this effect. Our findings suggest that the cytoprotective effects of HO-1 are mediated by suppression of TNF/TNFR1-mediated apoptotic signaling, specifically by modulating apoptotic DISC formation and mitochondrial TNFR1 translocation during hepatic I/R.

  19. TNFα as a Physiological Regulator of Hematopoietic Progenitor Cells:Increase of Early Hematopoietic Progenitor Cells in TNFR55--/-mice in vivo and Potent Inhibition of Progenitor Cell Proliferation by TNFα in Vitro

    Institute of Scientific and Technical Information of China (English)

    ZhangY; HaradaA; BluuethmannH; WangJ.B; NakaoS

    1995-01-01

    Murine lineage marker (Lin)--Sca-1+c-kit+and Lin-Sca-1-c-kit+ cens represent the primitive hematopoietic stem cells (HSC)and coommitted hematopoietic progenitor cells(HPC),respectively. The number of Lin-Sca-1+c-kit+HSCs in bone marrow was significantly increased (2.9folds) in tumor necrosis factor(TNF)-receptor-55(TNF-R55)-deficient mice compared with that of wildtype ones without marked change in cellularity of bone marrow.

  20. Molecular characterization and functional analysis of tumor necrosis factor receptor-associated factor 2 in the Pacific oyster.

    Science.gov (United States)

    Huang, Baoyu; Zhang, Linlin; Du, Yishuai; Li, Li; Tang, Xueying; Zhang, Guofan

    2016-01-01

    Tumor necrosis factor receptor (TNFR)-associated factors (TRAFs) are a family of crucial adaptors, playing vital roles in mediating signal transduction in immune signaling pathways, including RIG-I-like receptor (RLR) signaling pathway. In the present study, a new TRAF family member (CgTRAF2) was identified in the Pacific oyster, Crassostrea gigas. Comparison and phylogenetic analysis revealed that CgTRAF2 could be a new member of the invertebrate TRAF2 family. Quantitative real-time PCR revealed that CgTRAF2 mRNA was highly expressed in the digestive gland, gills, and hemocytes, and it was significantly up-regulated after Vibrio alginolyticus and ostreid herpesvirus 1 (OsHV-1) challenge. The CgTRAF2 mRNA expression profile in different developmental stages of oyster larvae suggested that CgTRAF2 could function in early larval development. CgTRAF2 mRNA expression pattern, after the silence of CgMAVS (Mitochondrial Antiviral Signaling) -like, indicated that CgTRAF2 might function downstream of CgMAVS-like. Moreover, the subcellular localization analysis revealed that CgTRAF2 was localized in cytoplasm, and it may play predominately important roles in signal transduction. Collectively, these results demonstrated that CgTRAF2 might play important roles in the innate immunity and larval development of the Pacific oyster.

  1. Soluble tumor necrosis factor (TNF) receptors are effective therapeutic agents in lethal endotoxemia and function simultaneously as both TNF carriers and TNF antagonists.

    Science.gov (United States)

    Mohler, K M; Torrance, D S; Smith, C A; Goodwin, R G; Stremler, K E; Fung, V P; Madani, H; Widmer, M B

    1993-08-01

    Two forms (monomeric or dimeric) of the extracellular, ligand-binding portion of the human p80 cell-surface receptor for TNF were used to antagonize TNF activity in vitro and in vivo. The dimeric sTNFR:Fc molecule was a more potent inhibitor of TNF than the monomeric sTNFR (50 to 1000x), as assessed in vitro by inhibition of TNF binding or bioactivity and in vivo by protection of mice from an otherwise lethal injection of LPS. Surprisingly, the dimeric sTNFR:Fc construct demonstrated a beneficial effect even when administered 3 h after a lethal LPS injection (i.e., after serum TNF levels had peaked and receded). To study the mechanism by which the soluble TNFR functions in vivo, serum TNF levels were examined in mice given LPS in the presence or absence of soluble receptor. Administration of a mortality-reducing dose of sTNFR:Fc ablated the rise in serum TNF bioactivity that normally occurs in response to LPS. However, TNF bioactivity was revealed in these "TNF-negative" serum samples when the L929 bioassay was modified by inclusion of a mAb that blocks the binding of murine TNF to the human soluble TNFReceptor. These results indicate that the absence of direct cytolytic activity in the L929 assay was caused by neutralization of TNF, rather than to an absence of TNF in the serum. Moreover, administration of either monomeric sTNFR or low doses of dimeric sTNFR:Fc actually resulted in increased serum TNF levels compared to mice given LPS but no soluble receptor. However, these "agonistic" doses of soluble receptor did not lead to increased mortality when an LD60 dose of LPS was given. Thus, dimeric sTNFR are effective inhibitors of TNF and under some circumstances function simultaneously as both TNF "carriers" and antagonists of TNF biologic activity.

  2. Role of TNF-α/TNFR1 in intense acute swimming-induced delayed onset muscle soreness in mice.

    Science.gov (United States)

    Borghi, Sergio M; Zarpelon, Ana C; Pinho-Ribeiro, Felipe A; Cardoso, Renato D R; Martins-Pinge, Marli C; Tatakihara, Roberto I; Cunha, Thiago M; Ferreira, Sergio H; Cunha, Fernando Q; Casagrande, Rubia; Verri, Waldiceu A

    2014-04-10

    The injection of cytokines such as TNF-α induces muscle pain. Herein, it was addressed the role of endogenous TNF-α/TNFR1 signaling in intense acute swimming-induced muscle mechanical hyperalgesia in mice. Mice were exposed to water during 30 s (sham) or to a single session of 30-120 min of swimming. Intense acute swimming induced a dose-dependent (time of exercise-dependent) muscle mechanical hyperalgesia, which peaked after 24 h presenting characteristics of delayed onset muscle soreness (DOMS). The intense acute swimming (120 min)-induced muscle mechanical hyperalgesia was reduced in etanercept (soluble TNF receptor) treated and TNFR1 deficient ((-/-)) mice. TNF-α levels increased 2 and 4 h after intense acute swimming in soleus muscle (but not in gastrocnemius), and spinal cord, respectively. Exercise induced an increase of myeloperoxidase activity and decrease in reduced glutathione levels in an etanercept-sensitive and TNFR1-dependent manners in the soleus muscle, but not in the gastrocnemius muscle. Concluding, TNF-α/TNFR1 signaling mediates intense acute swimming-induced DOMS by an initial role in the soleus muscle followed by spinal cord, inducing muscle inflammatory hyperalgesia and oxidative stress. The knowledge of these mechanisms might contribute to improve the training of athletes, individuals with physical impairment and intense training such as military settings.

  3. Induction of apoptosis by furanodiene in HL60 leukemia cells through activation of TNFR1 signaling pathway

    Institute of Scientific and Technical Information of China (English)

    MA En-long; WANG Xiao-long; LI Yan-chun; TAI Wen-jiao; LI Te; GUO Tao

    2008-01-01

    Objective Curcuma wenyujin, named Ezhu in Chinese, a traditional Chinese medicine, which has been shown to possess antiearcinogenie activity and used for the treatment of tumor in China,for example, hepatic cancer and leukemia. β-elemene, a component of Curcuma wenyujin, was largely reported as a main active component for anti-tumor effect of Curcuma wenyujin. However, furanodiene, another main component of Curcuma wenyujin, was seldom investigated for its anti-tumor activities. In the present study, we aim to investigate the effect of furanodiene on human leukemia HL60 cells and to study the accurate molecular mechanisms of its action. Methods Trypan blue exclusion experiment was used for cell growth inhibition assay. The apoptotic characterizations were assessed by flow cytometry analysis, AO/EB staining assay and agarose gel eleetrophoresis assay. The expression of apoptosis-related proteins and the release of cytochrome c from mitochondrial were detected by western blotting, and the mRNA levels of TNF-α and TNFR1 were probed by RT-PCR. Formation of TNFR1 complex was analyzed by using immunoprecipitation of TNFR1 with TRRF1/2 and RIP. Results Furanodiene (10-100μM) treatment inhibited the growth of HL60 cells in a concentration-dependent manner. The effect of furanodiene on HL60 cells was associated with the induction of apoptosis, which was characterized by DNA fragmentation, cleavage of poly (ADP-ribose) polymerase (PARP), caspase-3, caspase-8 and caspase-9. In the Bcl-2 family proteins, Bid protein (a substrate of caspase-8) was activated by furanodiene, but Bcl-2, Bax and Bcl-xL proteins were not inuenced by furanodiene stimulation. Furanodiene elicited cytochrome c release from mitochondria into the cytosol. Moreover, furanodiene treatment caused the upregulation of TNFR1, the formation of TNFR1 complex and an obvious production of TNF-a in HL60 cells. The soluble TNFR1 receptor effectively inhibited furanodiene-induced apoptosis. Conclusions Furanodiene

  4. Microglia-derived proinflammatory cytokines tumor necrosis factor-alpha and interleukin-1beta induce Purkinje neuronal apoptosis via their receptors in hypoxic neonatal rat brain.

    Science.gov (United States)

    Kaur, Charanjit; Sivakumar, Viswanathan; Zou, Zhirong; Ling, Eng-Ang

    2014-01-01

    The developing cerebellum is extremely vulnerable to hypoxia which can damage the Purkinje neurons. We hypothesized that this might be mediated by tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) derived from activated microglia as in other brain areas. One-day-old rats were subjected to hypoxia following, which the expression changes of various proteins in the cerebellum including hypoxia inducible factor-1α, TNF-α, IL-1β, TNF-R1 and IL-1R1 were analyzed. Following hypoxic exposure, TNF-α and IL-1β immunoexpression in microglia was enhanced coupled by that of TNF-R1 and IL-1R1 in the Purkinje neurons. Along with this, hypoxic microglia in vitro showed enhanced release of TNF-α and IL-1β whose receptor expression was concomitantly increased in the Purkinje neurons. In addition, nitric oxide (NO) level was significantly increased in the cerebellum and cultured microglia subjected to hypoxic exposure. Moreover, cultured Purkinje neurons treated with conditioned medium derived from hypoxic microglia underwent apoptosis but the incidence was significantly reduced when the cells were treated with the same medium that was neutralized with TNF-α/IL-1β antibody. We conclude that hypoxic microglia in the neonatal cerebellum produce increased amounts of NO, TNF-α and IL-1β which when acting via their respective receptors could induce Purkinje neuron death.

  5. Soluble Tumor Necrosis Factor Receptor 1 Released by Skin-Derived Mesenchymal Stem Cells Is Critical for Inhibiting Th17 Cell Differentiation.

    Science.gov (United States)

    Ke, Fang; Zhang, Lingyun; Liu, Zhaoyuan; Yan, Sha; Xu, Zhenyao; Bai, Jing; Zhu, Huiyuan; Lou, Fangzhou; Cai, Wei; Sun, Yang; Gao, Yuanyuan; Wang, Hong; Wang, Honglin

    2016-03-01

    T helper 17 (Th17) cells play an important role in multiple sclerosis (MS) and its animal model experimental autoimmune encephalomyelitis (EAE). Th17 cell differentiation from naïve T cells can be induced in vitro by the cytokines transforming growth factor β1 and interleukin-6. However, it remains unclear whether other regulatory factors control the differentiation of Th17 cells. Mesenchymal stem cells (MSCs) have emerged as a promising candidate for inhibiting Th17 cell differentiation and autoimmune diseases. Despite the fact that several molecules have been linked to the immunomodulatory function of MSCs, many other key MSC-secreted regulators that are involved in inhibiting Th17 cell polarization are ill-defined. In this study, we demonstrated that the intraperitoneal administration of skin-derived MSCs (S-MSCs) substantially ameliorated the development of EAE in mice. We found that the proinflammatory cytokine tumor necrosis factor (TNF)-α, a key mediator in the pathophysiology of MS and EAE, was capable of promoting Th17 cell differentiation. Moreover, under inflammatory conditions, we demonstrated that S-MSCs produced high amounts of soluble TNF receptor 1 (sTNFR1), which binds TNF-α and antagonizes its function. Knockdown of sTNFR1 in S-MSCs decreased their inhibitory effect on Th17 cell differentiation ex vivo and in vivo. Thus, our data identified sTNFR1 and its target TNF-α as critical regulators for Th17 cell differentiation, suggesting a previously unrecognized mechanism for MSC therapy in Th17-mediated autoimmune diseases.

  6. Tumor necrosis factor α sensitizes spinal cord TRPV1 receptors to the endogenous agonist N-oleoyldopamine

    Directory of Open Access Journals (Sweden)

    Spicarova Diana

    2010-08-01

    Full Text Available Abstract Modulation of synaptic transmission in the spinal cord dorsal horn is thought to be involved in the development and maintenance of different pathological pain states. The proinflamatory cytokine, tumor necrosis factor α (TNFα, is an established pain modulator in both the peripheral and the central nervous system. Up-regulation of TNFα and its receptors (TNFR in dorsal root ganglion (DRG cells and in the spinal cord has been shown to play an important role in neuropathic and inflammatory pain conditions. Transient receptor potential vanilloid 1 (TRPV1 receptors are known as molecular integrators of nociceptive stimuli in the periphery, but their role on the spinal endings of nociceptive DRG neurons is unclear. The endogenous TRPV1 receptor agonist N-oleoyldopamine (OLDA was shown previously to activate spinal TRPV1 receptors. In our experiments the possible influence of TNFα on presynaptic spinal cord TRPV1 receptor function was investigated. Using the patch-clamp technique, miniature excitatory postsynaptic currents (mEPSCs were recorded in superficial dorsal horn neurons in acute slices after incubation with 60 nM TNFα. A population of dorsal horn neurons with capsaicin sensitive primary afferent input recorded after the TNFα pretreatment had a basal mEPSC frequency of 1.35 ± 0.20 Hz (n = 13, which was significantly higher when compared to a similar population of neurons in control slices (0.76 ± 0.08 Hz; n = 53; P

  7. Tnfa signaling through tnfr2 protects skin against oxidative stress-induced inflammation.

    Directory of Open Access Journals (Sweden)

    Sergio Candel

    2014-05-01

    Full Text Available TNFα overexpression has been associated with several chronic inflammatory diseases, including psoriasis, lichen planus, rheumatoid arthritis, and inflammatory bowel disease. Paradoxically, numerous studies have reported new-onset psoriasis and lichen planus following TNFα antagonist therapy. Here, we show that genetic inhibition of Tnfa and Tnfr2 in zebrafish results in the mobilization of neutrophils to the skin. Using combinations of fluorescent reporter transgenes, fluorescence microscopy, and flow cytometry, we identified the local production of dual oxidase 1 (Duox1-derived H₂O₂ by Tnfa- and Tnfr2-deficient keratinocytes as a trigger for the activation of the master inflammation transcription factor NF-κB, which then promotes the induction of genes encoding pro-inflammatory molecules. In addition, pharmacological inhibition of Duox1 completely abrogated skin inflammation, placing Duox1-derived H₂O₂ upstream of this positive feedback inflammatory loop. Strikingly, DUOX1 was drastically induced in the skin lesions of psoriasis and lichen planus patients. These results reveal a crucial role for TNFα/TNFR2 axis in the protection of the skin against DUOX1-mediated oxidative stress and could establish new therapeutic targets for skin inflammatory disorders.

  8. Tnfa Signaling Through Tnfr2 Protects Skin Against Oxidative Stress–Induced Inflammation

    Science.gov (United States)

    López-Muñoz, Azucena; García-Moreno, Diana; Espín-Palazón, Raquel; Tyrkalska, Sylwia D.; Cayuela, María L.; Renshaw, Stephen A.; Corbalán-Vélez, Raúl; Vidal-Abarca, Inmaculada; Tsai, Huai-Jen; Meseguer, José; Sepulcre, María P.; Mulero, Victoriano

    2014-01-01

    TNFα overexpression has been associated with several chronic inflammatory diseases, including psoriasis, lichen planus, rheumatoid arthritis, and inflammatory bowel disease. Paradoxically, numerous studies have reported new-onset psoriasis and lichen planus following TNFα antagonist therapy. Here, we show that genetic inhibition of Tnfa and Tnfr2 in zebrafish results in the mobilization of neutrophils to the skin. Using combinations of fluorescent reporter transgenes, fluorescence microscopy, and flow cytometry, we identified the local production of dual oxidase 1 (Duox1)-derived H2O2 by Tnfa- and Tnfr2-deficient keratinocytes as a trigger for the activation of the master inflammation transcription factor NF-κB, which then promotes the induction of genes encoding pro-inflammatory molecules. In addition, pharmacological inhibition of Duox1 completely abrogated skin inflammation, placing Duox1-derived H2O2 upstream of this positive feedback inflammatory loop. Strikingly, DUOX1 was drastically induced in the skin lesions of psoriasis and lichen planus patients. These results reveal a crucial role for TNFα/TNFR2 axis in the protection of the skin against DUOX1-mediated oxidative stress and could establish new therapeutic targets for skin inflammatory disorders. PMID:24802997

  9. TNF/TNFR{sub 1} pathway and endoplasmic reticulum stress are involved in ofloxacin-induced apoptosis of juvenile canine chondrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fu-Tao; Ding, Yi; Shah, Zahir; Xing, Dan; Gao, Yuan; Liu, Dong Ming; Ding, Ming-Xing, E-mail: dmx@mail.hzau.edu.cn

    2014-04-15

    Background and purpose: Quinolones cause obvious cartilaginous lesions in juvenile animals by chondrocyte apoptosis, which results in the restriction of their use in pediatric and adolescent patients. Studies showed that chondrocytes can be induced to produce TNFα, and the cisternae of the endoplasmic reticulum in quinolone-treated chondrocytes become dilated. We investigated whether TNF/TNFR{sub 1} pathway and endoplasmic reticulum stress (ERs) are involved in ofloxacin (a typical quinolone)-induced apoptosis of juvenile canine chondrocytes. Experimental approach: Canine juvenile chondrocytes were treated with ofloxacin. Cell survival and apoptosis rates were determined with MTT method and flow cytometry, respectively. The gene expression levels of the related signaling molecules (TNFα, TNFR{sub 1}, TRADD, FADD and caspase-8) in death receptor pathways and main apoptosis-related molecules (calpain, caspase-12, GADD153 and GRP78) in ERs were measured by qRT-PCR. The gene expression of TNFR{sub 1} was suppressed with its siRNA. The protein levels of TNFα, TNFR{sub 1} and caspase-12 were assayed using Western blotting. Key results: The survival rates decreased while apoptosis rates increased after the chondrocytes were treated with ofloxacin. The mRNA levels of the measured apoptosis-related molecules in death receptor pathways and ERs, and the protein levels of TNFα, TNFR{sub 1} and caspase-12 increased after the chondrocytes were exposed to ofloxacin. The downregulated mRNA expressions of TNFR{sub 1}, Caspase-8 and TRADD, and the decreased apoptosis rates of the ofloxacin-treated chondrocytes occurred after TNFR{sub 1}–siRNA interference. Conclusions and implications: Ofloxacin-induced chondrocyte apoptosis in a time- and concentration-dependent fashion. TNF/TNFR{sub 1} pathway and ERs are involved in ofloxacin-induced apoptosis of juvenile canine chondrocytes in the early stage. - Highlights: • Chondrocyte apoptosis is induced by ofloxacin in a time- and

  10. Role of TNF-alpha receptors in mice intoxicated with the parkinsonian toxin MPTP.

    Science.gov (United States)

    Rousselet, Estelle; Callebert, Jacques; Parain, Karine; Joubert, Chantal; Hunot, Stéphane; Hartmann, Andreas; Jacque, Claude; Perez-Diaz, Fernando; Cohen-Salmon, Charles; Launay, Jean-Marie; Hirsch, Etienne C

    2002-09-01

    The loss of dopaminergic neurons in Parkinson's disease is associated with a glial reaction and the overproduction of proinflammatory cytokines such as tumor necrosis factor alpha (TNF-alpha). TNF-alpha acts via two different receptors, TNFR1 and TNFR2, and is believed to have both a neuroprotective and a deleterious role for neurons. In order to analyze the putative role of TNF-alpha in parkinsonism, we compared the effect of the parkinsonian drug 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in mice lacking TNFR1, TNFR2, or both receptors and in wild-type littermates. We show that MPTP does not affect spontaneous activity or anxiety in any of the groups and that it reduces motor activity on a rotarod in double knock out mice but not in mice lacking only one receptor. Postmortem analysis revealed no differences in the number of nigral dopaminergic neurons whatever the group. In contrast, striatal dopamine level was slightly decreased in double knock-out mice and more reduced by MPTP in this group than in the other groups of mice. In addition, dopamine turnover was significantly more increased in double knock out mice after MPTP injection. These data suggest that TNF-alpha does not participate in the death of dopaminergic neurons in parkinsonism but that it slightly alters dopamine metabolism or the survival of dopaminergic terminals by a mechanism involving both receptors.

  11. TNF-TNFR2/p75 signaling inhibits early and increases delayed nontargeted effects in bone marrow-derived endothelial progenitor cells.

    Science.gov (United States)

    Sasi, Sharath P; Song, Jin; Park, Daniel; Enderling, Heiko; McDonald, J Tyson; Gee, Hannah; Garrity, Brittany; Shtifman, Alexander; Yan, Xinhua; Walsh, Kenneth; Natarajan, Mohan; Kishore, Raj; Goukassian, David A

    2014-05-16

    TNF-α, a pro-inflammatory cytokine, is highly expressed after being irradiated (IR) and is implicated in mediating radiobiological bystander responses (RBRs). Little is known about specific TNF receptors in regulating TNF-induced RBR in bone marrow-derived endothelial progenitor cells (BM-EPCs). Full body γ-IR WT BM-EPCs showed a biphasic response: slow decay of p-H2AX foci during the initial 24 h and increase between 24 h and 7 days post-IR, indicating a significant RBR in BM-EPCs in vivo. Individual TNF receptor (TNFR) signaling in RBR was evaluated in BM-EPCs from WT, TNFR1/p55KO, and TNFR2/p75KO mice, in vitro. Compared with WT, early RBR (1-5 h) were inhibited in p55KO and p75KO EPCs, whereas delayed RBR (3-5 days) were amplified in p55KO EPCs, suggesting a possible role for TNFR2/p75 signaling in delayed RBR. Neutralizing TNF in γ-IR conditioned media (CM) of WT and p55KO BM-EPCs largely abolished RBR in both cell types. ELISA protein profiling of WT and p55KO EPC γ-IR-CM over 5 days showed significant increases in several pro-inflammatory cytokines, including TNF-α, IL-1α (Interleukin-1 alpha), RANTES (regulated on activation, normal T cell expressed and secreted), and MCP-1. In vitro treatments with murine recombinant (rm) TNF-α and rmIL-1α, but not rmMCP-1 or rmRANTES, increased the formation of p-H2AX foci in nonirradiated p55KO EPCs. We conclude that TNF-TNFR2 signaling may induce RBR in naïve BM-EPCs and that blocking TNF-TNFR2 signaling may prevent delayed RBR in BM-EPCs, conceivably, in bone marrow milieu in general.

  12. A TNFR2-Agonist Facilitates High Purity Expansion of Human Low Purity Treg Cells.

    Directory of Open Access Journals (Sweden)

    Xuehui He

    Full Text Available Regulatory T cells (Treg are important for immune homeostasis and are considered of great interest for immunotherapy. The paucity of Treg numbers requires the need for ex vivo expansion. Although therapeutic Treg flow-sorting is feasible, most centers aiming at Treg-based therapy focus on magnetic bead isolation of CD4+CD25+ Treg using a good manufacturing practice compliant closed system that achieves lower levels of cell purity. Polyclonal Treg expansion protocols commonly use anti-CD3 plus anti-CD28 monoclonal antibody (mAb stimulation in the presence of rhIL-2, with or without rapamycin. However, the resultant Treg population is often heterogeneous and pro-inflammatory cytokines like IFNγ and IL-17A can be produced. Hence, it is crucial to search for expansion protocols that not only maximize ex vivo Treg proliferative rates, but also maintain Treg stability and preserve their suppressive function. Here, we show that ex vivo expansion of low purity magnetic bead isolated Treg in the presence of a TNFR2 agonist mAb (TNFR2-agonist together with rapamycin, results in a homogenous stable suppressive Treg population that expresses FOXP3 and Helios, shows low expression of CD127 and hypo-methylation of the FOXP3 gene. These cells reveal a low IL-17A and IFNγ producing potential and hardly express the chemokine receptors CCR6, CCR7 and CXCR3. Restimulation of cells in a pro-inflammatory environment did not break the stability of this Treg population. In a preclinical humanized mouse model, the TNFR2-agonist plus rapamycin expanded Treg suppressed inflammation in vivo. Importantly, this Treg expansion protocol enables the use of less pure, but more easily obtainable cell fractions, as similar outcomes were observed using either FACS-sorted or MACS-isolated Treg. Therefore, this protocol is of great interest for the ex vivo expansion of Treg for clinical immunotherapy.

  13. A TNFR2-Agonist Facilitates High Purity Expansion of Human Low Purity Treg Cells.

    Science.gov (United States)

    He, Xuehui; Landman, Sija; Bauland, Stijn C G; van den Dolder, Juliette; Koenen, Hans J P M; Joosten, Irma

    2016-01-01

    Regulatory T cells (Treg) are important for immune homeostasis and are considered of great interest for immunotherapy. The paucity of Treg numbers requires the need for ex vivo expansion. Although therapeutic Treg flow-sorting is feasible, most centers aiming at Treg-based therapy focus on magnetic bead isolation of CD4+CD25+ Treg using a good manufacturing practice compliant closed system that achieves lower levels of cell purity. Polyclonal Treg expansion protocols commonly use anti-CD3 plus anti-CD28 monoclonal antibody (mAb) stimulation in the presence of rhIL-2, with or without rapamycin. However, the resultant Treg population is often heterogeneous and pro-inflammatory cytokines like IFNγ and IL-17A can be produced. Hence, it is crucial to search for expansion protocols that not only maximize ex vivo Treg proliferative rates, but also maintain Treg stability and preserve their suppressive function. Here, we show that ex vivo expansion of low purity magnetic bead isolated Treg in the presence of a TNFR2 agonist mAb (TNFR2-agonist) together with rapamycin, results in a homogenous stable suppressive Treg population that expresses FOXP3 and Helios, shows low expression of CD127 and hypo-methylation of the FOXP3 gene. These cells reveal a low IL-17A and IFNγ producing potential and hardly express the chemokine receptors CCR6, CCR7 and CXCR3. Restimulation of cells in a pro-inflammatory environment did not break the stability of this Treg population. In a preclinical humanized mouse model, the TNFR2-agonist plus rapamycin expanded Treg suppressed inflammation in vivo. Importantly, this Treg expansion protocol enables the use of less pure, but more easily obtainable cell fractions, as similar outcomes were observed using either FACS-sorted or MACS-isolated Treg. Therefore, this protocol is of great interest for the ex vivo expansion of Treg for clinical immunotherapy.

  14. Tumor necrosis factor-α inhibits angiotensin II receptor type 1 expression in dorsal root ganglion neurons via β-catenin signaling.

    Science.gov (United States)

    Yang, Y; Wu, H; Yan, J-Q; Song, Z-B; Guo, Q-L

    2013-09-17

    Both tumor necrosis factor (TNF)-α and the angiotensin (Ang) II/angiotensin II receptor type 1 (AT1) axis play important roles in neuropathic pain and nociception. In the present study, we explored the interaction between the two systems by examining the mutual effects between TNF-α and the Ang II/AT1 receptor axis in dorsal root ganglion (DRG) neurons. Rat DRG neurons were treated with TNF-α in different concentrations for different lengths of time in the presence or absence of transcription inhibitor actinomycin D, TNF receptor 1 (TNFR1) inhibitor SPD304, β-catenin signaling inhibitor CCT031374, or different kinase inhibitors. TNF-α decreased the AT1 receptor mRNA level as well as the AT1a receptor promoter activity in a dose-dependent manner within 30 h, which led to dose-dependent inhibition of Ang II-binding AT1 receptor level on the cell membrane. Actinomycin D (1 mg/ml), SPD304 (50 μM), p38 mitogen-activated protein kinase (MAPK) inhibitor PD169316 (25 μM), and CCT031374 (50 μM) completely abolished the inhibitory effect of TNF-α on AT1 receptor expression. TNF-α dose-dependently increased soluble β-catenin and phosphorylated GSK-3β levels, which was blocked by SPD304 and PD169316. In DRG neurons treated with AT2 receptor agonist CGP421140, or Ang II with or without AT1 receptor antagonist losartan or AT2 receptor antagonist PD123319 for 30 h, we found that Ang II and Ang II+PD123319 significantly decreased TNF-α expression, whereas CPG421140 and Ang II+losartan increased TNF-α expression. In conclusion, we demonstrate that TNF-α inhibits AT1 receptor expression at the transcription level via TNFR1 in rat DRG neurons by increasing the soluble β-catenin level through the p38 MAPK/GSK-3β pathway. In addition, Ang II appears to inhibit and induce TNF-α expression via the AT1 receptor and the AT2 receptor in DRG neurons, respectively. This is the first evidence of crosstalk between TNF-α and the Ang II/AT receptor axis in DRG neurons.

  15. Expression of tumor necrosis factor receptor-immunoglobulin G1 Fc fusion protein in glycoengineered Pichia pastoris%人Ⅱ型肿瘤坏死因子受体-免疫球蛋白G1Fc融合蛋白在糖基工程化毕赤酵母中的表达

    Institute of Scientific and Technical Information of China (English)

    高新; 宋海峰; 林殿海; 杨小盼; 万德友; 陈枢青

    2012-01-01

    Objective To express the tumor necrosis factor receptor-immunoglobulin Gl Fc fusion ( TNFR-Fc ) in Pichia pastoris and study the effect of N-glycoengineered process on the protein bioactⅣity. Methods The cDNA encoding TNFR-Fc fusion protein was subcloned into pPIC6αA vector to construct the expression plasmid pPIC6-TF that was transformed into the GSB, a glycoengineered P. pastoris strain. Positive colonies were selected by YPD culture containing blasti-cidin and further screened by induced expression on cellulose acetate and nitrocellulose membrane with HRP labeled human IgG. The TNFR-Fc/GSB57 strain, whose expression level was higher, was cultured in 10L fermentor. Purified TNFR-Fc was obtained by Protein A affinity chromatography from the fermentation. Results BioactⅣity analysis showed that the purified protein could neutralize the cytotoxicity of 5×104U /L TNFα to L929 cells ( EC50 1.48 μmol/L). Conclusion The activity of recombinant TNFR-Fc expressed in glycoengineered P. pastoris is higher than that of the wild type one, but still lower than that expressed in CHO. N-glycan should be further modified.%目的 在糖基工程化毕赤酵母中表达人Ⅱ型肿瘤坏死因子受体-免疫球蛋白G1 Fc融合蛋白(tumor necrosis factor receptor-immunoglobulin G1 Fc fusion,TNFR-Fc),考察糖基工程化过程对其活性的影响.方法 将编码TNFR-Fc的cDNA序列插入毕赤酵母表达载体pPIC6αA中,构建重组表达质粒pPIC6-TF.用表达质粒转染N-糖基化工程改造的毕赤酵母菌株GSB,在含有杀稻瘟菌素的YPD平板上进行筛选.然后再使用HRP标记的羊抗人IgG在醋酸-硝酸纤维素双层膜上进行斑点印迹(dot-blot)筛选.选择表达量较高的工程菌株TNFR-Fc/GSB57进行高密度培养,通过Protein A亲和层析从发酵上清中纯化融合蛋白,利用鼠L929细胞对融合蛋白的抗TNFα活性进行分析.结果 通过筛选获得了表达人Ⅱ型肿瘤坏死因子受体-Fc融合蛋白的表达

  16. Silencer of death domains controls cell death through tumour necrosis factor-receptor 1 and caspase-10 in acute lymphoblastic leukemia.

    Directory of Open Access Journals (Sweden)

    Adam Cisterne

    Full Text Available Resistance to apoptosis remains a significant problem in drug resistance and treatment failure in malignant disease. NO-aspirin is a novel drug that has efficacy against a number of solid tumours, and can inhibit Wnt signaling, and although we have shown Wnt signaling to be important for acute lymphoblastic leukemia (ALL cell proliferation and survival inhibition of Wnt signaling does not appear to be involved in the induction of ALL cell death. Treatment of B lineage ALL cell lines and patient ALL cells with NO-aspirin induced rapid apoptotic cell death mediated via the extrinsic death pathway. Apoptosis was dependent on caspase-10 in association with the formation of the death-inducing signaling complex (DISC incorporating pro-caspase-10 and tumor necrosis factor receptor 1 (TNF-R1. There was no measurable increase in TNF-R1 or TNF-α in response to NO-aspirin, suggesting that the process was ligand-independent. Consistent with this, expression of silencer of death domain (SODD was reduced following NO-aspirin exposure and lentiviral mediated shRNA knockdown of SODD suppressed expansion of transduced cells confirming the importance of SODD for ALL cell survival. Considering that SODD and caspase-10 are frequently over-expressed in ALL, interfering with these proteins may provide a new strategy for the treatment of this and potentially other cancers.

  17. Cellular inhibitors of apoptosis are global regulators of NF-κB and MAPK activation by members of the TNF family of receptors.

    Science.gov (United States)

    Varfolomeev, Eugene; Goncharov, Tatiana; Maecker, Heather; Zobel, Kerry; Kömüves, László G; Deshayes, Kurt; Vucic, Domagoj

    2012-03-20

    Tumor necrosis factor (TNF) family members are essential for the development and proper functioning of the immune system. TNF receptor (TNFR) signaling is mediated through the assembly of protein signaling complexes that activate the nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) pathways in a ubiquitin-dependent manner. The cellular inhibitor of apoptosis (c-IAP) proteins c-IAP1 and c-IAP2 are E3 ubiquitin ligases that are recruited to TNFR signaling complexes through their constitutive association with the adaptor protein TNFR-associated factor 2 (TRAF2). We demonstrated that c-IAP1 and c-IAP2 were required for canonical activation of NF-κB and MAPK by members of the TNFR family. c-IAPs were required for the recruitment of inhibitor of κB kinase β (IKKβ), the IKK regulatory subunit NF-κB essential modulator (NEMO), and RBCK1/Hoil1-interacting protein (HOIP) to TNFR signaling complexes and the induction of gene expression by TNF family members. In contrast, TNFRs that stimulated the noncanonical NF-κB pathway triggered translocation of c-IAPs, TRAF2, and TRAF3 from the cytosol to membrane fractions, which led to their proteasomal and lysosomal degradation. Finally, we established that signaling by B cell-activating factor receptor 3 induced the cytosolic depletion of TRAF3, which enabled noncanonical NF-κB activation. These results define c-IAP proteins as critical regulators of the activation of NF-κB and MAPK signaling pathways by members of the TNFR superfamily.

  18. Structural insights of homotypic interaction domains in the ligand-receptor signal transduction of tumor necrosis factor (TNF)

    Science.gov (United States)

    Park, Young-Hoon; Jeong, Mi Suk; Jang, Se Bok

    2016-01-01

    Several members of tumor necrosis factor receptor (TNFR) superfamily that these members activate caspase-8 from death-inducing signaling complex (DISC) in TNF ligand-receptor signal transduction have been identified. In the extrinsic pathway, apoptotic signal transduction is induced in death domain (DD) superfamily; it consists of a hexahelical bundle that contains 80 amino acids. The DD superfamily includes about 100 members that belong to four subfamilies: death domain (DD), caspase recruitment domain (CARD), pyrin domain (PYD), and death effector domain (DED). This superfamily contains key building blocks: with these blocks, multimeric complexes are formed through homotypic interactions. Furthermore, each DD-binding event occurs exclusively. The DD superfamily regulates the balance between death and survival of cells. In this study, the structures, functions, and unique features of DD superfamily members are compared with their complexes. By elucidating structural insights of DD superfamily members, we investigate the interaction mechanisms of DD domains; these domains are involved in TNF ligand-receptor signaling. These DD superfamily members play a pivotal role in the development of more specific treatments of cancer. [BMB Reports 2016; 49(3): 159-166] PMID:26615973

  19. Apigenin induces apoptosis via tumor necrosis factor receptor- and Bcl-2-mediated pathway and enhances susceptibility of head and neck squamous cell carcinoma to 5-fluorouracil and cisplatin.

    Science.gov (United States)

    Chan, Leong-Perng; Chou, Tzung-Han; Ding, Hsiou-Yu; Chen, Pin-Ru; Chiang, Feng-Yu; Kuo, Po-Lin; Liang, Chia-Hua

    2012-07-01

    Apigenin, a natural plant flavone, may have chemopreventive and therapeutic potentials for anti-inflammatory, antioxidant, and anti-cancer. Nevertheless, the anti-tumor effect of apigenin on human head and neck squamous cell carcinoma (HNSCC) is not fully understood. The antioxidant capacity and protective effects of apigenin against oxidative stress in murine normal embryonic liver BNLCL2 cells are examined. Cell viability, morphologic change, clonogenic survival, cell cycle distribution, reactive oxygen species (ROS) production, glutathione formation, and death receptors- and Bcl-2-mediated caspase pathways of HNSCC SCC25 cells and A431 cells with apigenin are investigated. Apigenin inhibits the growth of SCC25 and A431 cells and induces cell cycle arrest in the G2/M phase. Apigenin has an antioxidant capacity as well as the ability to inhibit lipid peroxidation. It protects BNLCL2 cells against oxidative damage, and is potentially able to prevent cancer. Apigenin increases intracellular ROS levels and reduces levels of glutathione; it also induces cell apoptosis via tumor necrosis factor receptor (TNF-R)-, TNF-related apoptosis-inducing ligand receptor (TRAIL-R)-, and Bcl-2-mediated caspase-dependent cell death pathways in SCC25 cells. The combination of apigenin with 5-fluorouracil (5-Fu) or cisplatin induces the dramatic death of SCC25 cells. Apigenin induces SCC25 cell apoptosis via the up-regulation of both TNF-R and TRAIL-R signaling pathways, and has a synergistic effect on the inhibition of cell proliferation in combination with 5-Fu or cisplatin. These analytical findings suggest that apigenin may be a good therapeutic agent against HNSCC cells. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Impact of tumor necrosis factor receptor p55 deficiency in susceptibility of C57BL/6 mice to infection with Leishmania (Leishmania) amazonensis.

    Science.gov (United States)

    Cargnelutti, Diego Esteban; Salomón, María Cristina; Celedon, Verónica; Cuello-Carrión, Fernando Darío; Gea, Susana; Di Genaro, María Silvia; Scodeller, Eduardo Alberto

    2016-04-01

    Tumor necrosis factor (TNF) is involved in host resistance to several intracellular pathogens. Although the critical role of TNF receptor (TNFR)p55 in Leishmania (Leishmania) major infection has been demonstrated, the impact of TNFRp55 deficiency on L. (L.) amazonensis infection has not been explored. L. (L.) amazonensis-infected TNFRp55(-/-) mice failed to resolve lesions, whereas C57BL/6 wild-type mice completely healed. The susceptibility of the TNFRp55(-/-) mice was characterized by higher lesion size and histopathological damage in comparison with the wild-type mice. A marked increased of the splenic index was observed in the TNFRp55(-/-) mice after 15 weeks infection. These results show that in the absence of TNFRp55, L. (L.) amazonensis-infected knockout mice fail to resolve lesions, whereas wild-type mice completely heal.

  1. Differential role of tumor necrosis factor receptors in mouse brain inflammatory responses in cryolesion brain injury

    DEFF Research Database (Denmark)

    Quintana, Albert; Giralt, Mercedes; Rojas, Santiago

    2005-01-01

    Tumor necrosis factor-alpha (TNF-alpha) is one of the mediators dramatically increased after traumatic brain injury that leads to the activation, proliferation, and hypertrophy of mononuclear, phagocytic cells and gliosis. Eventually, TNF-alpha can induce both apoptosis and necrosis via intracell......Tumor necrosis factor-alpha (TNF-alpha) is one of the mediators dramatically increased after traumatic brain injury that leads to the activation, proliferation, and hypertrophy of mononuclear, phagocytic cells and gliosis. Eventually, TNF-alpha can induce both apoptosis and necrosis via...... signaling also affected the expression of apoptosis/cell death-related genes (Fas, Rip, p53), matrix metalloproteinases (MMP3, MMP9, MMP12), and their inhibitors (TIMP1), suggesting a role of TNFR1 in extracellular matrix remodeling after injury. However, GDNF, NGF, and BDNF expression were not affected...... by TNFR1 deficiency. Overall, these results suggest that TNFR1 is involved in the early establishment of the inflammatory response and that its deficiency causes a decreased inflammatory response and tissue damage following brain injury....

  2. Molecular mechanism of signaling by tumor necrosis factor

    Institute of Scientific and Technical Information of China (English)

    ZHA; Jikun(查纪坤); SHU; Hongbing(舒红兵)

    2002-01-01

    Tumor necrosis factor (TNF) is an important cytokine with multiple biological effects,including cell growth,differentiation,apoptosis,immune regulation and induction of inflammation. The effects of TNF are mediated by two receptors,TNF-R1 and TNF-R2. The major signal transduction pathways triggered by TNF include those that lead to apoptosis,activation of transcription factor NF-??B and protein kinase JNK. This review will discuss the molecular mechanisms of these signaling pathways.

  3. Inhibition of soluble tumor necrosis factor ameliorates synaptic alterations and Ca2+ dysregulation in aged rats.

    Directory of Open Access Journals (Sweden)

    Diana M Sama

    Full Text Available The role of tumor necrosis factor α (TNF in neural function has been investigated extensively in several neurodegenerative conditions, but rarely in brain aging, where cognitive and physiologic changes are milder and more variable. Here, we show that protein levels for TNF receptor 1 (TNFR1 are significantly elevated in the hippocampus relative to TNF receptor 2 (TNFR2 in aged (22 months but not young adult (6 months Fischer 344 rats. To determine if altered TNF/TNFR1 interactions contribute to key brain aging biomarkers, aged rats received chronic (4-6 week intracranial infusions of XPro1595: a soluble dominant negative TNF that preferentially inhibits TNFR1 signaling. Aged rats treated with XPro1595 showed improved Morris Water Maze performance, reduced microglial activation, reduced susceptibility to hippocampal long-term depression, increased protein levels for the GluR1 type glutamate receptor, and lower L-type voltage sensitive Ca(2+ channel (VSCC activity in hippocampal CA1 neurons. The results suggest that diverse functional changes associated with brain aging may arise, in part, from selective alterations in TNF signaling.

  4. Epidermal Growth Factor Receptor in Pancreatic Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira-Cunha, Melissa, E-mail: melissacunha@doctors.org.uk [Hepatobiliary Surgery Unit, Manchester Royal Infirmary, Oxford Road, Manchester, M13 9WL (United Kingdom); Newman, William G. [Genetic Medicine, MAHSC, University of Manchester, St Mary' s Hospital, Oxford Road, Manchester, M13 9WL (United Kingdom); Siriwardena, Ajith K. [Hepatobiliary Surgery Unit, Manchester Royal Infirmary, Oxford Road, Manchester, M13 9WL (United Kingdom)

    2011-03-24

    Pancreatic cancer is the fourth leading cause of cancer related death. The difficulty in detecting pancreatic cancer at an early stage, aggressiveness and the lack of effective therapy all contribute to the high mortality. Epidermal growth factor receptor (EGFR) is a transmembrane glycoprotein, which is expressed in normal human tissues. It is a member of the tyrosine kinase family of growth factors receptors and is encoded by proto-oncogenes. Several studies have demonstrated that EGFR is over-expressed in pancreatic cancer. Over-expression correlates with more advanced disease, poor survival and the presence of metastases. Therefore, inhibition of the EGFR signaling pathway is an attractive therapeutic target. Although several combinations of EGFR inhibitors with chemotherapy demonstrate inhibition of tumor-induced angiogenesis, tumor cell apoptosis and regression in xenograft models, these benefits remain to be confirmed. Multimodality treatment incorporating EGFR-inhibition is emerging as a novel strategy in the treatment of pancreatic cancer.

  5. Targeting signaling factors for degradation, an emerging mechanism for TRAF functions

    OpenAIRE

    Yang, Xiao-Dong; Sun, Shao-Cong

    2015-01-01

    Tumor necrosis factor receptor (TNFR)-associated factors (TRAFs) form a family of proteins that are best known as signaling adapters of TNFRs. However, emerging evidence suggests that TRAF proteins, particularly TRAF2 and TRAF3, also regulate signal transduction by controlling the fate of intracellular signaling factors. A well-recognized function of TRAF2 and TRAF3 in this aspect is to mediate ubiquitin-dependent degradation of NF-κB-inducing kinase (NIK), an action required for the control ...

  6. Epigallocatechin-3-Gallate Attenuates the Effects of TNF-α in Vascular Endothelial Cells by Causing Ectodomain Shedding of TNF Receptor 1

    Directory of Open Access Journals (Sweden)

    Won Seok Yang

    2016-05-01

    Full Text Available Background/Aims: We investigated the mechanism underlying anti-tumor necrosis factor-α (TNF-α effects of epigallocatechin-3-gallate (EGCG in human aortic endothelial cells. Methods: Tumor necrosis factor receptor 1 (TNFR1 was assessed by Western blot analysis. Cytosolic Ca2+ was measured using Fluo-4 AM. A disintegrin and metalloprotease 10 (ADAM10 was localized by immunofluorescence staining. Results: EGCG caused ectodomain shedding of TNFR1 within 30 min and attenuated TNF-α-induced endothelin-1 (ET-1 expression. EGCG-induced TNFR1 ectodomain shedding was prevented by BAPTA-AM (intracellular Ca2+ chelator, but not by the absence of extracellular Ca2+. In physiologic extracellular Ca2+ concentration, EGCG markedly increased cytosolic Ca2+. Even in the absence of extracellular Ca2+, EGCG raised cytosolic Ca2+, though less potently. siRNA depletion of ADAM10 prevented EGCG-induced ectodomain shedding of TNFR1 and also diminished the inhibitory effect of EGCG on TNF-α-induced ET-1 expression. EGCG caused translocation of ADAM10 to the plasma membrane, and this effect was prevented by BAPTA-AM. Besides extracellular Ca2+ influx, release of intracellular stored Ca2+ caused ADAM10-dependent ectodomain shedding of TNFR1. Conclusion: EGCG decreases the responsiveness of cells to TNF-α by causing ADAM10-dependent ectodomain shedding of TNFR1. This effect was attributed to its property to increase cytosolic Ca2+ through both extracellular Ca2+ influx and release of stored Ca2+.

  7. Cellular signaling by fibroblast growth factor receptors.

    Science.gov (United States)

    Eswarakumar, V P; Lax, I; Schlessinger, J

    2005-04-01

    The 22 members of the fibroblast growth factor (FGF) family of growth factors mediate their cellular responses by binding to and activating the different isoforms encoded by the four receptor tyrosine kinases (RTKs) designated FGFR1, FGFR2, FGFR3 and FGFR4. Unlike other growth factors, FGFs act in concert with heparin or heparan sulfate proteoglycan (HSPG) to activate FGFRs and to induce the pleiotropic responses that lead to the variety of cellular responses induced by this large family of growth factors. A variety of human skeletal dysplasias have been linked to specific point mutations in FGFR1, FGFR2 and FGFR3 leading to severe impairment in cranial, digital and skeletal development. Gain of function mutations in FGFRs were also identified in a variety of human cancers such as myeloproliferative syndromes, lymphomas, prostate and breast cancers as well as other malignant diseases. The binding of FGF and HSPG to the extracellular ligand domain of FGFR induces receptor dimerization, activation and autophosphorylation of multiple tyrosine residues in the cytoplasmic domain of the receptor molecule. A variety of signaling proteins are phosphorylated in response to FGF stimulation including Shc, phospholipase-Cgamma, STAT1, Gab1 and FRS2alpha leading to stimulation of intracellular signaling pathways that control cell proliferation, cell differentiation, cell migration, cell survival and cell shape. The docking proteins FRS2alpha and FRS2beta are major mediators of the Ras/MAPK and PI-3 kinase/Akt signaling pathways as well as negative feedback mechanisms that fine-tune the signal that is initiated at the cell surface following FGFR stimulation.

  8. Fibroblast growth factor 23 and its receptors.

    Science.gov (United States)

    Yu, Xijie; White, Kenneth E

    2005-08-01

    Fibroblast growth factor 23 (FGF23) is a circulating factor that plays critical roles in phosphate and vitamin D metabolism, as evidenced by the fact that FGF23 missense mutations cause autosomal dominant hypophosphatemic rickets (ADHR). Autosomal dominant hypophosphatemic rickets is characterized by hypophosphatemia with inappropriately normal 1,25-dihydroxyvitamin D concentrations, as well as bone pain, fracture and rickets. This phenotype parallels that of patients with tumor induced osteomalacia (TIO), X-linked hypophosphatemic rickets (XLH), and fibrous dysplasia (FD), in whom elevated serum FGF23 levels are often observed. The fibroblast growth factor receptors (FGFR1-4) play key roles in skeletal development, as well as in normal metabolic processes. Several FGFR isoforms that potentially mediate the activity of FGF23 have been implicated. In the short term, these findings will lead to further understanding of FGF23 function, and potentially in the long term, to targeted therapies in disorders of hypo- and hyperphosphatemia that involve FGF23.

  9. Apoptosis in experimental NASH is associated with p53 activation and TRAIL receptor expression.

    Science.gov (United States)

    Farrell, Geoffrey C; Larter, Claire Z; Hou, Jing Yun; Zhang, Rena H; Yeh, Matthew M; Williams, Jacqueline; dela Pena, Aileen; Francisco, Rona; Osvath, Sarah R; Brooling, John; Teoh, Narcissus; Sedger, Lisa M

    2009-03-01

    We examined extrinsic and intrinsic (endogenous) mitochondrial apoptosis pathways in experimental non-alcoholic steatohepatitis (NASH). To assess extrinsic pathways, we measured hepatic expression of death-inducing cytokine receptors (tumor necrosis factor-alpha-receptor (TNF-R)1, TNF-R2, Fas, and TNFalpha-related apoptosis-inducing ligand-receptor (TRAIL-R) mRNA, TUNEL, caspase 3 activation, liver injury and liver pathology in mice fed a methionine and choline deficient (MCD) diet. For endogenous stress pathways, we determined serum insulin-like growth factor-1 (IGF-1), hepatic p53, Bcl-XL, tBid and p21 expression. Methionine and choline deficient feeding increased alanine aminotransferase (ALT) and apoptosis from day 10, without increases in TNF-R1, TNF-R2, and Fas. However, murine TRAIL receptors, particularly decoyTRAIL-R1/TNFRSFH23 and Killer/DR5 mRNA increased. MCD feeding enhanced hepatic p53 expression, corresponding to approximately 50% fall in serum IGF-1, decreased Bcl-XL, enhanced Bid cleavage to tBid, and up-regulation of p21. Nutritional restitution experiments showed that correcting either methionine or choline deficiency suppressed liver inflammation (extrinsic pathway), but failed to correct apoptosis, IGF-1 or p53. Methionine and choline deficiency lower IGF-1 to de-repress p53 during induction of steatohepatitis. The p53 induced by nutritional stress is biologically active in mediating mitochondrial cell death pathways, but may also be responsible for TRAIL receptor expression, thereby linking intrinsic and exogenous apoptosis pathways in NASH.

  10. Isoforms of receptors of fibroblast growth factors.

    Science.gov (United States)

    Gong, Siew-Ging

    2014-12-01

    The breadth and scope of Fibroblast Growth Factor signaling is immense, with documentation of its role in almost every organism and system studied so far. FGF ligands signal through a family of four distinct tyrosine kinase receptors, the FGF receptors (FGFRs). One contribution to the diversity of function and signaling of FGFs and their receptors arises from the numerous alternative splicing variants that have been documented in the FGFR literature. The present review discusses the types and roles of alternatively spliced variants of the FGFR family members and the significant impact of alternative splicing on the physiological functions of five broad classes of FGFR isoforms. Some characterized known regulatory mechanisms of alternative splicing and future directions in studies of FGFR alternative splicing are also discussed. Presence, absence, and/or the combination of specific exons within each FGFR protein impart upon each individual isoform its unique function and expression pattern during normal function and in diseased states (e.g., in cancers and birth defects). A better understanding of the diversity of FGF signaling in different developmental contexts and diseased states can be achieved through increased knowledge of the presence of specific FGFR isoforms and their impact on downstream signaling and functions. Modern high-throughput techniques afford an opportunity to explore the distribution and function of isoforms of FGFR during development and in diseases.

  11. Vitamin D-induced ectodomain shedding of TNF receptor 1 as a nongenomic action: D3 vs D2 derivatives.

    Science.gov (United States)

    Yang, Won Seok; Yu, Hoon; Kim, Jin Ju; Lee, Mee Jeong; Park, Su-Kil

    2016-01-01

    As a nongenomic action, 1,25-dihydroxyvitamin D3 (1,25D3) induces L-type Ca(2+) channel-mediated extracellular Ca(2+) influx in human aortic smooth muscle cells (HASMCs), which activates a disintegrin and metalloprotease 10 (ADAM10) to cleave and shed the ectodomain of tumor necrosis factor receptor 1 (TNFR1). In this study, we examined the potencies of other vitamin D3 and D2 analogs to stimulate the ectodomain shedding of TNFR1 in HASMCs. 25-Hydroxyvitamin D3 (25D3), a precursor of 1,25D3, and elocalcitol, an analog of 1,25D3, caused ectodomain shedding of TNFR1 within 30 min, whereas 1,25-dihydroxyvitamin D2 (1,25D2) and paricalcitol, a derivative of 1,25D2, did not. Both 25D3 and elocalcitol rapidly induced extracellular Ca(2+) influx and markedly increased intracellular Ca(2+), while 1,25D2 and paricalcitol caused only small increases in intracellular Ca(2+). 25D3- and elocalcitol-induced TNFR1 ectodomain sheddings were abolished by verapamil and in Ca(2+)-free media. Both 25D3 and elocalcitol caused the translocation of ADAM10 to the cell surface, which was inhibited by verapamil, while 1,25D2 and paricalcitol did not cause ADAM10 translocation. When ADAM10 was depleted by ADAM10-siRNA, 25D3 and elocalcitol could not induce ectodomain shedding of TNFR1. The plasma membrane receptor, endoplasmic reticulum stress protein 57 (ERp57), but not the classic vitamin D receptor, mediated the nongenomic action of vitamin D to induce ectodomain shedding of TNFR1. In summary, like 1,25D3, 25D3 and elocalcitol caused ADAM10-mediated ectodomain shedding of TNFR1, whereas 1,25D2 and paricalcitol did not. The difference may depend on their affinities to ERp57 through which extracellular Ca(2+) influx is induced.

  12. Local TNFR1 Signaling Licenses Murine Neutrophils for Increased TLR-Dependent Cytokine and Eicosanoid Production.

    Science.gov (United States)

    Deguine, Jacques; Wei, Jessica; Barbalat, Roman; Gronert, Karsten; Barton, Gregory M

    2017-02-20

    Neutrophils are generally the first immune cells recruited during the development of sterile or microbial inflammation. As these cells express many innate immune receptors with the potential to directly recognize microbial or endogenous signals, we set out to assess whether their functions are locally influenced by the signals present at the onset of inflammation. Using a mouse model of peritonitis, we demonstrate that neutrophils elicited in the presence of C-type lectin receptor ligands have an increased ability to produce cytokines, chemokines, and lipid mediators in response to subsequent TLR stimulation. Importantly, we found that licensing of cytokine production was mediated by paracrine TNF-α-TNFR1 signaling rather than direct ligand sensing, suggesting a form of quorum sensing among neutrophils. Mechanistically, licensing was largely imparted by changes in the posttranscriptional regulation of inflammatory cytokines, whereas production of IL-10 was regulated at the transcriptional level. Altogether, our data suggest that neutrophils rapidly adapt their functions to the local inflammatory milieu. These phenotypic changes may promote rapid neutrophil recruitment in the presence of pathogens but limit inflammation in their absence.

  13. TNF-alpha: an activator of CD4+FoxP3+TNFR2+ regulatory T cells.

    Science.gov (United States)

    Chen, Xin; Oppenheim, Joost J

    2010-01-01

    TNF-alpha (TNF) is a pleiotropic cytokine which can have proinflammatory or immunosuppressive effects, depending on the context, duration of exposure and disease state. The basis for the opposing actions of TNF remains elusive. The growing appreciation of CD4+FoxP3+ regulatory T cells (Tregs), which comprise approximately 10% of peripheral CD4 cells, as pivotal regulators of immune responses has provided a new framework to define the cellular and molecular basis underlying the contrasting action of TNF. TNF by itself can overcome the profound anergic state of T cell receptor-stimulated Tregs. Furthermore, in concert with IL-2, TNF selectively activates Tregs, resulting in proliferation, upregulation of FoxP3 expression and increases in their suppressive activity. Both human and mouse Tregs predominantly express TNFR2, making it possible for TNF to enhance Treg activity, which helps limit the collateral damage caused by excessive immune responses and eventually terminates immune response. TNFR2-expressing CD4+FoxP3+ Tregs comprise approximately 40% of peripheral Tregs in normal mice and present the maximally suppressive subset of Tregs. In this review, studies describing the action of TNF on Treg function will be discussed. The role of Tregs in the autoimmune disorders and cancer as well as the effect of anti-TNF therapy on Tregs, especially in rheumatoid arthritis, will also be considered. Copyright (c) 2010 S. Karger AG, Basel.

  14. The Curative Effect of Recombinant Human Tumor Necrosis Factor (rhTNFR:Fc) Protein in the Treatment of Activity Rheumatoid Arthritis%重组人Ⅱ型肿瘤坏死因子受体-抗体融合蛋白治疗活动性类风湿性关节炎效果观察

    Institute of Scientific and Technical Information of China (English)

    吴春叶; 李力

    2010-01-01

    目的 研究重组人Ⅱ型肿瘤坏死因子受体-抗体融合蛋白(rhTNFR:Fc)对活动性类风湿关节炎(RA)的疗效.方法 40例活动性RA随机分为两组,观察组皮下注射rhTNFR: Fc 25 mg,2次/周;对照组口服来氟米特(LEFT)20 mg,1/d及甲氨蝶呤(MTX)15 mg,1次/周.疗程为24周.治疗2、4、8、12、24周后,统计两组达到美国风湿病学会(ACR)20、ACR 50、ACR 70改善标准的情况.结果 治疗2、4 周后, 观察组ACR 20的比例明显高于对照组,差异有统计学意义(P<0.05);治疗8周后,观察组ACR 20、50的比例均明显高于对照组,差异有统计学意义(P<0.05);治疗24周后,观察组ACR 20、50、70的比例均显著高于对照组,差异有统计学意义(P<0.05).对照组中的消化道症状发生率明显高于观察组(P<0.05).结论 rhTNFR: Fc对活动性RA具有良好的疗效及安全性.

  15. Circulating interleukin-6 and tumor necrosis factor receptor-1 predict ...

    African Journals Online (AJOL)

    EL-HAKIM

    history taking, clinical examination, and routine investigations (CBC, ESR,. CRP, Widal test and ... patients than in control children, and in resistant cases than in responsive cases (before and 5 ... appetite, constipation or diarrhea and abdominal pain. 2. Physical .... TNF-R1, during acute typhoid illness which decreased with ...

  16. Soluble and cell surface receptors for tumor necrosis factor

    DEFF Research Database (Denmark)

    Wallach, D; Engelmann, H; Nophar, Y

    1991-01-01

    Tumor necrosis factor (TNF) initiates its multiple effects on cell function by binding at a high affinity to specific cell surface receptors. Two different molecular species of these receptors, which are expressed differentially in different cells, have been identified. The cDNAs of both receptor...... have recently been cloned. Antibodies to one of these receptor species (the p55, type I receptor) can trigger a variety of TNF like effects by cross-linking of the receptor molecules. Thus, it is not TNF itself but its receptors that provide the signal for the response to this cytokine...... in certain pathological situations. Release of the soluble receptors from the cells seems to occur by proteolytic cleavage of the cell surface forms and appears to be a way of down-regulating the cell response to TNF. Because of their ability to bind TNF, the soluble receptors exert an inhibitory effect...

  17. Cardiovascular risk factors regulate the expression of vascular endothelin receptors

    DEFF Research Database (Denmark)

    Xu, Cang-Bao; Sun, Yang; Edvinsson, Lars

    2010-01-01

    , cigarette smoking and hypertension (both strongly related to arterial wall injury), inflammation and atherosclerosis. The vascular endothelin receptors are a protein family that belongs to the larger family of G-protein coupled receptors. They mediate vascular smooth muscle contraction, proliferation......-activated protein kinase pathways and downstream transcription factors such as nuclear factor-kappaB. Understanding the mechanisms involved in vascular endothelin receptor upregulation during cardiovascular disease may provide novel therapeutic approaches....

  18. Effects of Tumor Necrosis Factor-α on Podocyte Expression of Monocyte Chemoattractant Protein-1 and in Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    Choon Hee Chung

    2015-02-01

    Full Text Available Background/Aims: Tumor necrosis factor (TNF-α is believed to play a role in diabetic kidney disease. This study explores the specific effects of TNF-α with regard to nephropathy-relevant parameters in the podocyte. Methods: Cultured mouse podocytes were treated with recombinant TNF-α and assayed for production of monocyte chemoattractant protein-1 (MCP-1 by enzyme-linked immunosorbent assay (ELISA. TNF-α signaling of MCP-1 was elucidated by antibodies against TNF receptor (TNFR 1 or TNFR2 or inhibitors of nuclear factor-kappaB (NF-κB, phosphatidylinositol 3-kinase (PI3K or Akt. In vivo studies were done on male db/m and type 2 diabetic db/db mice. Levels of TNF-α and MCP-1 were measured by RT-qPCR and ELISA in the urine, kidney and plasma of the two cohorts and correlated with albuminuria. Results: Podocytes treated with TNF-α showed a robust increase (∼900% in the secretion of MCP-1, induced in a dose- and time-dependent manner. Signaling of MCP-1 expression occurred through TNFR2, which was inducible by TNF-α ligand, but did not depend on TNFR1. TNF-α then proceeded via the NF-κB and the PI3K/Akt systems, based on the effectiveness of the inhibitors of those pathways. For in vivo relevance to diabetic kidney disease, TNF-α and MCP-1 levels were found to be elevated in the urine of db/db mice but not in the plasma. Conclusion: TNF-α potently stimulates podocytes to produce MCP-1, utilizing the TNFR2 receptor and the NF-κB and PI3K/Akt pathways. Both TNF-α and MCP-1 levels were increased in the urine of diabetic db/db mice, correlating with the severity of diabetic albuminuria.

  19. Pattern of hormone receptors and human epidermal growth factor ...

    African Journals Online (AJOL)

    2015-02-05

    Feb 5, 2015 ... Key words: Breast cancer, human epidermal growth factor receptor 2/neu, immunohistochemistry, ... therapy.[6‑8] Of all these prognostic and predictive factors, ... one of the biggest private medical laboratories in Nigeria.

  20. Inhibition of tumor necrosis factor-α reduces alveolar septal cell apoptosis in passive smoking rats

    Institute of Scientific and Technical Information of China (English)

    ZHANG Cheng; CAI Shan; CHEN Ping; CHEN Jian-bo; WU Jie; WU Shang-jie; ZHOU Rui

    2008-01-01

    Background Recent studies have revealed that lung cell apoptosis plays an important role in pathogenesis of cigarette-induced chronic obstructive pulmonary disease (COPD).Tumor necrosis factor alpha(TNF-α)is one of the most important cytokines which are involved in COPD.This study aimed at investigating the jnfluence of its inhibitor,recombinant human necrosis factor-alpha receptor Ⅱ:IgG Fc fusion protein(rhTNFR:Fc)on alveolar septal cell apoptosis in passive smoking rats.Methods Forty-eight rats were randomly divided into a normal control group,a passive smoking group,an rhTNFR:Fc intervention group and a sham intervention group.The passive smoking rats were treated by exposure to cigarette smoking daily for 80 days.Afcer smoking for one month the rhTNFR:Fc Intervention group was treated with rhTNFR:Fc by subcutaneous injection,the sham intervention group injected subcutaneousIv with a neutral preparation(normal saline 0.1 ml,manicol 0.8 ml,cane sugar 0.2 mg,Tris 0.024 mg as a control.Lung function was determined and the levels of TNF-α in serum and broncho-alveolar lavage fluid(BALF)were measured with enzyme-linked immunosorbnent assay (ELISA).Lung tissue sections stained by hematoxylin and eosin(HE)were observed for study of morphological alternations.Mean linear intercept(MLI)and mean alveolar numbers(MAN)were measured and the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL)method was carried out to determine the percentage of positive cells and distribution of apoptotic cells.Results Increased MLI and decreased MAN were found in the passive smoking group compared with both the normal control group and the rhTNFR:Fc intervention group(P<0.05).Forced expiratory volume in 0.3 second(FEV0.3)/forced vital capacity(FVC)and peak expiratory flow(PEF)were lower in the passive smoking group than that in the normal control group(P<0.05).Compared with the sham intervention group,FEV0.3/FVC and PEF increased in the rhTNFR:Fc intervention

  1. Tumor necrosis factor (TNF) receptor shedding controls thresholds of innate immune activation that balance opposing TNF functions in infectious and inflammatory diseases

    DEFF Research Database (Denmark)

    Xanthoulea, Sofia; Pasparakis, Manolis; Kousteni, Stavroula

    2004-01-01

    ensues at the cost of disbalanced inflammatory reactions that lead to pathology. Mutant mice exhibit spontaneous hepatitis, enhanced susceptibility to endotoxic shock, exacerbated TNF-dependent arthritis, and experimental autoimmune encephalomyelitis. These results introduce a new concept for receptor...... shedding as a mechanism setting up thresholds of cytokine function to balance resistance and susceptibility to disease. Assessment of p55TNFR shedding may thus be of prognostic value in infectious, inflammatory, and autoimmune diseases....

  2. Dynamic cross-talk analysis among TNF-R, TLR-4 and IL-1R signalings in TNFα-induced inflammatory responses

    Directory of Open Access Journals (Sweden)

    Chuang Yung-Jen

    2010-05-01

    Full Text Available Abstract Background Development in systems biology research has accelerated in recent years, and the reconstructions for molecular networks can provide a global view to enable in-depth investigation on numerous system properties in biology. However, we still lack a systematic approach to reconstruct the dynamic protein-protein association networks at different time stages from high-throughput data to further analyze the possible cross-talks among different signaling/regulatory pathways. Methods In this study we integrated protein-protein interactions from different databases to construct the rough protein-protein association networks (PPANs during TNFα-induced inflammation. Next, the gene expression profiles of TNFα-induced HUVEC and a stochastic dynamic model were used to rebuild the significant PPANs at different time stages, reflecting the development and progression of endothelium inflammatory responses. A new cross-talk ranking method was used to evaluate the potential core elements in the related signaling pathways of toll-like receptor 4 (TLR-4 as well as receptors for tumor necrosis factor (TNF-R and interleukin-1 (IL-1R. Results The highly ranked cross-talks which are functionally relevant to the TNFα pathway were identified. A bow-tie structure was extracted from these cross-talk pathways, suggesting the robustness of network structure, the coordination of signal transduction and feedback control for efficient inflammatory responses to different stimuli. Further, several characteristics of signal transduction and feedback control were analyzed. Conclusions A systematic approach based on a stochastic dynamic model is proposed to generate insight into the underlying defense mechanisms of inflammation via the construction of corresponding signaling networks upon specific stimuli. In addition, this systematic approach can be applied to other signaling networks under different conditions in different species. The algorithm and method

  3. Proteolytic activation of proapoptotic kinase protein kinase Cδ by tumor necrosis factor α death receptor signaling in dopaminergic neurons during neuroinflammation

    Directory of Open Access Journals (Sweden)

    Gordon Richard

    2012-04-01

    Full Text Available Abstract Background The mechanisms of progressive dopaminergic neuronal loss in Parkinson’s disease (PD remain poorly understood, largely due to the complex etiology and multifactorial nature of disease pathogenesis. Several lines of evidence from human studies and experimental models over the last decade have identified neuroinflammation as a potential pathophysiological mechanism contributing to disease progression. Tumor necrosis factor α (TNF has recently emerged as the primary neuroinflammatory mediator that can elicit dopaminergic cell death in PD. However, the signaling pathways by which TNF mediates dopaminergic cell death have not been completely elucidated. Methods In this study we used a dopaminergic neuronal cell model and recombinant TNF to characterize intracellular signaling pathways activated during TNF-induced dopaminergic neurotoxicity. Etanercept and neutralizing antibodies to tumor necrosis factor receptor 1 (TNFR1 were used to block TNF signaling. We confirmed the results from our mechanistic studies in primary embryonic mesencephalic cultures and in vivo using the stereotaxic lipopolysaccharide (LPS model of nigral dopaminergic degeneration. Results TNF signaling in dopaminergic neuronal cells triggered the activation of protein kinase Cδ (PKCδ, an isoform of the novel PKC family, by caspase-3 and caspase-8 dependent proteolytic cleavage. Both TNFR1 neutralizing antibodies and the soluble TNF receptor Etanercept blocked TNF-induced PKCδ proteolytic activation. Proteolytic activation of PKCδ was accompanied by translocation of the kinase to the nucleus. Notably, inhibition of PKCδ signaling by small interfering (siRNA or overexpression of a PKCδ cleavage-resistant mutant protected against TNF-induced dopaminergic neuronal cell death. Further, primary dopaminergic neurons obtained from PKCδ knockout (−/− mice were resistant to TNF toxicity. The proteolytic activation of PKCδ in the mouse substantia nigra in the

  4. Liver safety of biosimilar of recombinanttumor necrosis factorreceptor-antibody fusion protein in Spondyloarthritis patients under different status of HBV infection: a prospective observational study%重组人Ⅱ型TNF-α受体-抗体融合蛋白对不同HBV感染状态下脊柱关节炎患者肝功能的影响

    Institute of Scientific and Technical Information of China (English)

    李艳华; 莫颖倩; 梁锦坚; 孙启阳; 黄月婷; 郑东辉; 戴冽

    2015-01-01

    目的 探讨国产重组Ⅱ型肿瘤坏死因子(TNF)受体-抗体融合蛋白(rh TNFR: Fc)对不同乙型肝炎病毒(HBV)感染状态下脊柱关节炎(SPA)患者肝功能及HBV感染的影响.方法 纳入2012年2月至2014年8月在中山大学孙逸仙纪念医院风湿免疫科就诊的活动期SpA患者,经rhTNFR:Fc单药或联合治疗至少12周,治疗前及治疗第4、12周(主要观察终点)评估SpA病情、肝功能及HBV感染指标.如患者同意,延长rh TNFR:Fc治疗并随访至第24周(次要观察终点).结果 81例患者完成12周随访,其中HBV携带组21例,既往HBV感染组25例,无HBV感染组35例.第4周时3组各1例丙氨酸转氨酶(ALT)升高但未超过3倍.治疗24周,既往感染组均无再激活,无感染组均无新感染,携带组4例出现再激活,均无伴ALT超过正常上限2倍,其中7例基线HBV-DNA阴性且未预防性抗病毒治疗者,2例患者分别于第10、24周时发生HBV再激活,HBV-DNA自行转阴或抗病毒治疗后转阴;1例rh TNFR:Fc联合沙利度胺12周后改沙利度胺维持,第16周发生HBV-DNA再激活,第24周自行转阴.4例基线HBV轻度复制的携带组患者均未发生再激活,9例基线HBV高复制者1例对预防性抗病毒药物耐药而出现再激活.结论 rh TNFR:Fc为基础的短期治疗可引起HBV再激活,但多不引起肝炎活动.%Objective To investigate the influence of recombinant human tumor necrosis factor α receptor-antibody fusion protein (rhTNFR: Fc) to the Hepatitis B virus (HBV) infection status and liver function of Spondyloarthritis (SpA) patients under different HBV infection status.Methods Active SpApatients with normal liver function were enrolled in Sun Yat-sen Memorial hospital from February 2012 to August 2014.All were treated with rhTNFR : Fc based therapy (monotherapy or combined therapy) for at least 12 weeks.SpA disease activity, HBV infection status and liver function were evaluated at each interview(baseline, 4th and 12th week, as

  5. Soluble TNF receptors are associated with infarct size and ventricular dysfunction in ST-elevation myocardial infarction.

    Directory of Open Access Journals (Sweden)

    Lennart Nilsson

    Full Text Available OBJECTIVES: The aim of the study was to investigate circulating markers of apoptosis in relation to infarct size, left ventricular dysfunction and remodeling in an ST-elevation myocardial infarction (STEMI population undergoing primary percutaneous coronary intervention (PCI. BACKGROUND: Immediate re-opening of the acutely occluded infarct-related artery via primary PCI is the treatment of choice in STEMI to limit ischemia injury. However, the sudden re-initiation of blood flow can lead to a local acute inflammatory response with further endothelial and myocardial damage, so-called reperfusion injury. Apoptosis is suggested to be a key event in ischemia-reperfusion injury, resulting in LV-dysfunction, remodeling and heart failure. METHODS: The present study is a prespecified substudy of the F.I.R.E. trial. We included 48 patients with STEMI undergoing primary PCI. Blood samples were collected prior to PCI and after 24 hours. Plasma was separated for later analysis of soluble tumor necrosis factor receptor (sTNFR 1, sTNFR2, sFas and sFas ligand (sFasL by ELISA. Infarct size, left ventricular (LV dysfunction and remodeling were assessed by cardiac magnetic resonance imaging at five days and four months after STEMI. RESULTS: The levels of sTNFR1 at 24 h as well as the relative increases in sTNFR1 and sTNFR2 over 24 h showed consistent and significant correlations with infarct size and LV-dysfunction at four months. Moreover, both sTNFRs correlated strongly with Troponin I and matrix metalloproteinase (MMP-2 measurements. Soluble Fas and sFasL did not overall correlate with measures of infarct size or LV-dysfunction. None of the apoptosis markers correlated significantly with measures of remodeling. CONCLUSIONS: In STEMI patients, circulating levels of sTNFR1 and sTNFR2 are associated with infarct size and LV dysfunction. This provides further evidence for the role of apoptosis in ischemia-reperfusion injury.

  6. Down regulation of epidermal growth factor receptors: direct demonstration of receptor degradation in human fibroblasts

    OpenAIRE

    1984-01-01

    The metabolism of the receptor for epidermal growth factor (EGF) has been measured by labeling the receptor in vivo with radioactive amino acid precursors and then determining, by immunoprecipitation with specific anti-EGF receptor antisera, the rate of degradation of the receptor when the cells are placed in a nonradioactive medium. In human fibroblasts the rate of EGF receptor degradation (t1/2 = 10.1 h) was faster than the rate of degradation of total cell protein. When EGF was added to th...

  7. 急性胰腺炎肺损伤大鼠肺组织肿瘤坏死因子受体-1与窖蛋白-1的表达及清胰汤的治疗作用%The expression of tumor necrosis factor receptor-1 and caveolin-1 in the lung of acute pancreatitisassociated lung injury rats and the therapeutic role of Qingyitang

    Institute of Scientific and Technical Information of China (English)

    王钢; 陈海龙; 唐颖; 任凤; 李洁; 姜妙娜

    2010-01-01

    Objective To investigate the expression and function of tumor necrosis factor receptor-1 (TNFR-1) and caveolin-1 (Cav-1) in the lung of acute pancreatitis-associated lung injury rats, and to determine the potential role of Qingyitang. Methods Wistar rats were randomly divided into sham operation (SHAM) group, acute lung injury (ALI) group, dexamethasone (DEX) group and Qingyitang (QYT)group. ALI was induced by retrograde injection of deoxycholate into biliopancreatic duct of rats. Blood and lung tissues were drawn after 24 h. Serum amylase, lung wet/dry (W/D) ratio and pathological section were examined to evaluate the degree of lung injury. Immunoradioassay was used to detect serum tumor necrosis factor-α (TNF-α). Reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were applied to detect the expression levels of TNFR-1 and Cav-1 mRNA and protein respectively. Results The concentration of serum amylase, the W/D ratio, TNF-α (4.82 ± 0.14 vs 2.96 ± 0. 30, P <0. 01 ) and the degree of pathological lung injury were obviously increased in ALI rats. The expression of TNFR-1 mRNA was increased in ALI rats (1.29 ±0. 15 vs 0.43 ±0.05,P<0.01), but Cav-1 mRNA expression was decreased ( 1.14 ±0. 10 vs 2.00 ±0. 10,P <0.01 ). The expression of TNFR-1 protein in both lipid rafts and non-lipid rafts was increased, but that of Cav-1 in both of the two fractions was decreased. As compared with ALI rats, the concentration of serum amylase, W/D ratio, TNF-αt ( DEX: 3.79 ± 0. 11,QYT: 3.66 ±0. 10, ALI: 4.82 ±0. 14,P <0.01 ) and the degree of pathological lung injury were obviously decreased in DEX and QYT rats. The expression of TNFR-1 mRNA was decreased in both DEX and QYT groups (DEX: 0.48±0.01, QYT: 0.49 ±0.02, ALI: 1.29 ±0. 15,P<0.01), but that of Cav-1 mRNA was up-regulated (DEX: 1.66 ±0.06, QYT: 1.52 ±0.04, ALI: 1.14 ±0. 10,P<0.01). The expression of TNFR-1 protein in both lipid rafts and non-lipid rafts was decreased, but

  8. Blocking TNF-α by combination of TNF-α- and TNFR-binding cyclic peptide ameliorates the severity of TNBS-induced colitis in rats.

    Science.gov (United States)

    Yin, Bingjiao; Hu, Xin; Wang, Jing; Liang, Huifang; Li, Xiaoyan; Niu, Nin; Li, Baihua; Jiang, Xiaodan; Li, Zhuoya

    2011-04-10

    Tumor necrosis factor alpha (TNF-α) has been implicated in the pathogenesis of Crohn's disease. TNF antagonists are effectively used to treat these patients, although the efficiency of different antagonists varies. In the present study we combined TNF-α binding cyclic peptide (TBCP) and TNFR1 binding cyclic peptide (TRBCP) to treat TNBS-induced colitis in rats for one week. The symptoms of colitis including bloody diarrhea, rectal prolapse, and a profound and sustained weight loss were significantly ameliorated and the colon inflammatory damage, both macroscopic and histological scores, MPO activity, and NO production were markedly decreased in rats by neutralization of TNF-α and blocking TNFR1, as compared with those in rats treated with irrelevant peptide or normal saline (Prats treated with both TBCP and TRBCP were also down-regulated (Prats treated with irrelevant peptide or normal saline. These findings suggest that the combination of TNF-α- and TNFR1-binding peptide effectively improves the symptoms of TNBS-induced colitis and alleviates colonic pathological damages in rats. This combination may be a potent candidate for clinical treatment of the inflammatory bowel disease.

  9. TNF-α type 2 receptor mediates renal inflammatory response to chronic angiotensin II administration with high salt intake in mice.

    Science.gov (United States)

    Singh, Purnima; Bahrami, Laleh; Castillo, Alexander; Majid, Dewan S A

    2013-04-01

    Tumor necrosis factor-alpha (TNF-α) has been implicated in salt-sensitive hypertension and renal injury (RI) induced by angiotensin II (ANG II). To determine the receptor type of TNF-α involved in this mechanism, we evaluated the responses to chronic ANG II infusion (25 ng/min by implanted minipump) given with high-salt diet (HS; 4% NaCl) for 2 wk in gene knockout mice for TNF-α receptor type 1 (TNFR1KO; n = 6) and type 2 (TNFR2KO; n = 6) and compared the responses with those in wild-type (WT; C57BL/6; n = 6) mice. Blood pressure in these mice was measured by implanted radiotelemetry as well as by tail-cuff plethysmography. RI responses were assessed by measuring macrophage cell infiltration (CD68(+) immunohistochemistry), glomerulosclerosis (PAS staining), and interstitial fibrosis (Gomori's trichrome staining) in renal tissues at the end of the treatment period. The increase in mean arterial pressure induced by ANG II + HS treatment was not different in these three groups of mice (TNFR1KO, 114 ± 1 to 161 ± 7 mmHg; TNFR2KO, 113 ± 1 to 161 ± 3 mmHg; WT, 110 ± 3 to 154 ± 3 mmHg). ANG II + HS-induced RI changes were similar in TNFR1KO mice but significantly less in TNFR2KO mice (macrophage infiltration, 0.02 ± 0.01 vs. 1.65 ± 0.45 cells/mm(2); glomerulosclerosis, 26.3 ± 2.6 vs. 35.7 ± 2.2% area; and interstitial fibrosis, 5.2 ± 0.6 vs. 8.1 ± 1.1% area) compared with the RI changes in WT mice. The results suggest that a direct activation of TNF-α receptors may not be required in inducing hypertensive response to chronic ANG II administration with HS intake, but the induction of inflammatory responses leading to renal injury are mainly mediated by TNF-α receptor type 2.

  10. the significance of epidermal growth factor receptor and survivin ...

    African Journals Online (AJOL)

    2013-01-01

    Jan 1, 2013 ... SURVIVIN EXPRESSION IN BLADDER CANCER TISSUE AND URINE ... Objective: To assess whether epidermal growth factor receptor (EGFR) and survivin ..... lung cancer by the FDA in 2003 (28) and is currently.

  11. In Entamoeba histolytica, a BspA family protein is required for chemotaxis toward tumour necrosis factor

    Directory of Open Access Journals (Sweden)

    Anne Silvestre

    2015-07-01

    Full Text Available Background: Entamoeba histolytica cell migration is essential for the development of human amoebiasis (an infectious disease characterized by tissue invasion and destruction. The tissue inflammation associated with tumour necrosis factor (TNF secretion by host cells is a well-documented feature of amoebiasis. Tumour necrosis factor is a chemoattractant for E. histolytica, and the parasite may have a TNF receptor at its cell surface. Methods: confocal microscopy, RNA Sequencing, bioinformatics, RNA antisense techniques and histological analysis of human colon explants were used to characterize the interplay between TNF and E. histolytica. Results: an antibody against human TNF receptor 1 (TNFR1 stained the E. histolytica trophozoite surface and (on immunoblots binds to a 150-kDa protein. Proteome screening with the TNFR1 sequence revealed a BspA family protein in E. histolytica that carries a TNFR signature domain and six leucine-rich repeats (named here as "cell surface protein", CSP, in view of its cellular location. Cell surface protein shares structural homologies with Toll-Like receptors, colocalizes with TNF and is internalized in TNF-containing vesicles. Reduction of cellular CSP levels abolished chemotaxis toward TNF and blocked parasite invasion of human colon. Conclusions: there is a clear link between TNF chemotaxis, CSP and pathogenesis.

  12. Activation of 5-HT7 receptors increases neuronal platelet-derived growth factor β receptor expression.

    Science.gov (United States)

    Vasefi, Maryam S; Kruk, Jeff S; Liu, Hui; Heikkila, John J; Beazely, Michael A

    2012-03-09

    Several antipsychotics have a high affinity for 5-HT7 receptors yet despite intense interest in the 5-HT7 receptor as a potential drug target to treat psychosis, the function and signaling properties of 5-HT7 receptors in neurons remain largely uncharacterized. In primary mouse hippocampal and cortical neurons, as well as in the SH-SY5Y cell line, incubation with 5-HT, 5-carboxamidotryptamine (5-CT), or 5-HT7 receptor-selective agonists increases the expression of platelet-derived growth factor (PDGF)β receptors. The increased PDGFβ receptor expression is cyclic AMP-dependent protein kinase (PKA)-dependent, suggesting that 5-HT7 receptors couple to Gα(s) in primary neurons. Interestingly, up-regulated PDGFβ receptors display an increased basal phosphorylation state at the phospholipase Cγ-activating tyrosine 1021. This novel linkage between the 5-HT7 receptor and the PDGF system may be an important GPCR-neurotrophic factor signaling pathway in neurons.

  13. TNFR1 mediates TNF-α-induced tumour lymphangiogenesis and metastasis by modulating VEGF-C-VEGFR3 signalling

    DEFF Research Database (Denmark)

    Ji, Hong; Cao, Renhai; Yang, Yunlong

    2014-01-01

    in Tnfr1(-/-) mice largely restores tumour lymphangiogenesis and lymphatic metastasis. These findings shed mechanistic light on the intimate interplay between inflammation and lymphangiogenesis in cancer metastasis, and propose therapeutic intervention of lymphatic metastasis by targeting the TNF-α-TNFR1...

  14. 斑马鱼TNFR2基因克隆及表达分析%Cloning and Expressing Analysis of TNFR2 Gene of Zebrafish

    Institute of Scientific and Technical Information of China (English)

    齐麟; 余英才; 向志明; 李军

    2013-01-01

    利用巢式PCR方法克隆斑马鱼(Danio rerio)肿瘤坏死因子受体2(TNFR2)基因,该基因全长1 242bp,编码413个氨基酸,分子质量44.68 ku,等电点5.90.实时荧光定量PCR结果表明,TNFR2基因在斑马鱼胚胎发育时期的表达量呈现下降后趋于稳定,在斑马鱼不同组织中均能检测到,并且表达丰度差别不大,在肌肉中表达量最高,在肠道中表达量最低.

  15. Soluble endoglin, transforming growth factor-Beta 1 and soluble tumor necrosis factor alpha receptors in different clinical manifestations of preeclampsia.

    Directory of Open Access Journals (Sweden)

    Luiza O Perucci

    Full Text Available BACKGROUND: Despite intensive research, the etiopathogenesis of preeclampsia (PE remains uncertain. Inflammatory and angiogenic factors are thought to play considerable roles in this disease. The objective of this study was to investigate the association between soluble endoglin (sEng, transforming growth factor beta-1 (TGF-β1 and tumor necrosis factor alpha soluble receptors (sTNF-Rs and the clinical manifestations of PE. METHODS: Plasma levels of sEng, TGF-β1 and sTNF-Rs were determined by ELISA in 23 non-pregnant, 21 normotensive pregnant and 43 PE women. PE women were stratified into subgroups according to the severity [mild (n = 12 and severe (n = 31] and onset-time of the disease [early (n = 19 and late (n = 24]. RESULTS: Pregnancy was associated with higher levels of sEng, sTNF-R1 and sTNF-R2 than the non-pregnant state. Moreover, PE women had higher levels of sEng and sTNF-R1 than normotensive pregnant women. No difference was found in TGF-β1 levels, comparing the three study groups. Late PE had higher levels of sTNF-R1 and sTNF-R2 than early PE. No significant differences were found in sEng and TGF-β1 comparing early and late PE. sEng levels were higher in severe PE than in mild PE and no difference was found for TGF-β1, sTNF-R1 and sTNF-R2 levels. There was a positive correlation among sEng, TNF-R1 and sTNF-2 levels. Logistic regression analysis revealed that primiparity and sEng levels are independently associated with the development of PE. Furthermore, sEng levels are independently associated with the disease severity. CONCLUSIONS: These results suggest that pregnancy is a condition associated with higher levels of anti-angiogenic and pro-inflammatory factors than the non-pregnant state and that PE is associated with an imbalance of these factors in the maternal circulation.

  16. Modulation of the NMDA Receptor Through Secreted Soluble Factors.

    Science.gov (United States)

    Cerpa, Waldo; Ramos-Fernández, Eva; Inestrosa, Nibaldo C

    2016-01-01

    Synaptic activity is a critical determinant in the formation and development of excitatory synapses in the central nervous system (CNS). The excitatory current is produced and regulated by several ionotropic receptors, including those that respond to glutamate. These channels are in turn regulated through several secreted factors that function as synaptic organizers. Specifically, Wnt, brain-derived neurotrophic factor (BDNF), fibroblast growth factor (FGF), and transforming growth factor (TGF) particularly regulate the N-methyl-D-aspartate receptor (NMDAR) glutamatergic channel. These factors likely regulate early embryonic development and directly control key proteins in the function of important glutamatergic channels. Here, we review the secreted molecules that participate in synaptic organization and discuss the cell signaling behind of this fine regulation. Additionally, we discuss how these factors are dysregulated in some neuropathologies associated with glutamatergic synaptic transmission in the CNS.

  17. Placental growth factor and vascular endothelial growth factor receptor-2 in human lung development.

    Science.gov (United States)

    Janér, Joakim; Andersson, Sture; Haglund, Caj; Karikoski, Riitta; Lassus, Patrik

    2008-08-01

    We examined the pulmonary expression of 2 proangiogenic factors, namely, placental growth factor and vascular endothelial growth factor receptor-2, during lung development and acute and chronic lung injury in newborn infants. Six groups were included in an immunohistochemical study of placental growth factor and vascular endothelial growth factor receptor-2, that is, 9 fetuses, 4 preterm and 8 term infants without lung injury who died soon after birth, 5 preterm infants with respiratory distress syndrome of 10 days, and 6 with bronchopulmonary dysplasia. Placental growth factor concentrations in tracheal aspirate fluid were measured in 70 samples from 20 preterm infants during the first postnatal week. In immunohistochemical analyses, placental growth factor staining was seen in bronchial epithelium and macrophages in all groups. Distal airway epithelium positivity was observed mostly in fetuses and in preterm infants who died soon after birth. Vascular endothelial growth factor receptor-2 staining was seen in vascular endothelium in all groups and also in lymphatic endothelium in fetuses. Vascular endothelial growth factor receptor-2 staining in arterial endothelium was associated with higher and staining in venous endothelium with lower gestational age. In capillaries, less vascular endothelial growth factor receptor-2 staining was seen in bronchopulmonary dysplasia. The mean placental growth factor protein concentration in tracheal aspirate fluid during the first postnatal week was 0.64 +/- 0.42 pg/mL per IgA-secretory component unit. Concentrations during the first postnatal week were stable. Lower placental growth factor concentrations correlated with chorioamnionitis and lactosyl ceramide positivity. The vascular endothelial growth factor receptor-2 staining pattern seems to reflect ongoing differentiation and activity of different endothelia. Lower vascular endothelial growth factor receptor-2 expression in capillary endothelium in bronchopulmonary dysplasia

  18. Curcumin Requires Tumor Necrosis Factor α Signaling to Alleviate Cognitive Impairment Elicited by Lipopolysaccharide

    Directory of Open Access Journals (Sweden)

    E.M. Kawamoto

    2012-05-01

    Full Text Available A decline in cognitive ability is a typical feature of the normal aging process, and of neurodegenerative disorders such as Alzheimer's, Parkinson's and Huntington's diseases. Although their etiologies differ, all of these disorders involve local activation of innate immune pathways and associated inflammatory cytokines. However, clinical trials of anti-inflammatory agents in neurodegenerative disorders have been disappointing, and it is therefore necessary to better understand the complex roles of the inflammatory process in neurological dysfunction. The dietary phytochemical curcumin can exert anti-inflammatory, antioxidant and neuroprotective actions. Here we provide evidence that curcumin ameliorates cognitive deficits associated with activation of the innate immune response by mechanisms requiring functional tumor necrosis factor α receptor 2 (TNFR2 signaling. In vivo, the ability of curcumin to counteract hippocampus-dependent spatial memory deficits, to stimulate neuroprotective mechanisms such as upregulation of BDNF, to decrease glutaminase levels, and to modulate N-methyl-D-aspartate receptor levels was absent in mice lacking functional TNFRs. Curcumin treatment protected cultured neurons against glutamate-induced excitotoxicity by a mechanism requiring TNFR2 activation. Our results suggest the possibility that therapeutic approaches against cognitive decline designed to selectively enhance TNFR2 signaling are likely to be more beneficial than the use of anti-inflammatory drugs per se.

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

    Science.gov (United States)

    Ceresa, Brian P; Peterson, Joanne L

    2014-01-01

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

  20. N-Glycosylation on different tumor necrosis factor receptor-Fc fusion protein: a preliminary analysis%不同肿瘤坏死因子受体-Fc融合蛋白N-糖基化修饰糖链的初步分析

    Institute of Scientific and Technical Information of China (English)

    何椿鹏; 华玲; 杨小盼; 万德有; 李萌萌; 王清清; 陈方; 董立厚; 高新

    2013-01-01

    目的 建立基于LC-MS的N-糖基化修饰糖链的分析方法,并比较不同肿瘤坏死因子受体(TNFR)-Fc融合蛋白N-糖基化修饰差异.方法 用肽-N-糖苷酶F释放糖蛋白中的修饰糖链,有机溶剂沉淀蛋白后,利用还原胺化反应将2-氨基苯甲酰胺标记至糖链上,并通过亲水作用萃取柱除去过量标记试剂,所得糖链采用ZIC-HILIC亲水作用色谱柱结合离子阱质谱进行分析.以市售TNFR-Fc融合蛋白为标准品,优化影响标记效率的各种因素后,对A和B两种TNFR-Fc融合蛋白制品的N-糖基化修饰糖链进行了分析和比较.结果 TNFR-Fc融合蛋白A和B中的修饰糖链主要含有岩藻糖、末端唾液酸、末端半乳糖、末端N-乙酰葡糖胺等糖型,且末端唾液酸含量相近,但融合蛋白A的岩藻糖和末端N-乙酰基葡萄糖的含量显著高于融合蛋白B,而融合蛋白B末端半乳糖含量高于融合蛋白A.结论 成功建立了基于LC-MS的N-糖基化修饰糖链的分析方法,该方法可有效分析糖蛋白中的修饰糖链类型和含量比例,对于详细表征糖蛋白药物结构及性质具有参考价值,并为进一步研究糖基化对糖蛋白药物药理活性以及药代动力学研究奠定了良好基础.%Objective To develop a method for N-glycans analysis based on LC-MS,and compare the N-glycans of different tumor necrosis factor receptor (TNFR)-Fc fusion proteins.Methods Glycans were released from TNFR-Fc fusion glycoproteins by PNGase F.Proteins were removed by precipitation with organic solvent and the oligosaccharides were evaporated to dryness and then labeled with 2-aminobenzamide.After excess 2-aminobenzamide was removed from the labeling samples by hydrophilic solid phase extraction column,the glycans were separated on ZIC-HILIC columns and then analyzed with linear ion trap mass spectrometer.The N-glycans analysis method was developed with the commercially available TNFR-Fc fusion glycoprotein,the factors affecting

  1. Nerve growth factor receptor molecules in rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Taniuchi, M.; Schweitzer, J.B.; Johnson, E.M. Jr.

    1986-03-01

    The authors have developed a method to immunoprecipitate rat nerve growth factor (NGF) receptor proteins and have applied the method to detect NGF receptor molecules in the rat brain. Crosslinking /sup 125/I-labeled NGF to either PC12 cells or cultured rat sympathetic neurons yielded two radiolabeled molecules (90 kDa and 220 kDa) that were immunoprecipitated by monoclonal antibody 192-IgG. Further, 192-IgG precipitated two radiolabeled proteins, with the expected sizes (80 kDa and 210 kDa) of noncrosslinked NGF receptor components, from among numerous surface-iodinated PC12 cell proteins. These results demonstrate the specific immunoprecipitation of NGF receptor molecules by 192-IgG. They applied the /sup 125/I-NGF crosslinking and 192-IgG-mediated immunoprecipitation procedures to plasma membrane preparations of rat brain: NGF receptor molecules of the same molecular masses as the peripheral receptor components were consistently detected in all regions and in preparations from whole brains. Removal of the peripheral sympathetic innervation of the brain did not eliminate these NGF receptor proteins, indicating that the receptor is endogenous to central nervous system tissues. They also observed retrograde transport of /sup 125/I-labeled 192-IgG from the parietal cortex to the nucleus basalis and from the hippocampus to the nucleus of the diagonal band of Broca and the medial septal nucleus. These findings demonstrate the presence in brain of NGF receptor molecules indistinguishable from those of the peripheral nervous system.

  2. [Research on the changes of IL-1 receptor and TNF-alpha receptor in rats with cerebral ischemia reperfusion and the chronergy of acupuncture intervention].

    Science.gov (United States)

    Wang, Zhan-Kui; Ni, Guang-Xia; Liu, Kun; Xiao, Zhen-Xin; Yang, Bao-Wang; Wang, Jing; Wang, Shu

    2012-11-01

    To explore the intervention timing of acupuncture in treatment of cerebral infarction and the relationship of cerebral ischemia reperfusion injury with inflammatory cytokine receptor. One hundred and ten male healthy Wistar rats were randomly divided into a normal group (n=10), a sham operation group (n=10), a model group (n=10), an acupuncture at non-acupoint group (non-acupoint group, n=40), an acupuncture with regaining consciousness method group (regaining consciousness group, n=40). Four subgroups were set up 1 h ischemia reperfusion in 1 h group, 3 h group, 6 h group, 12 h group in the two acupuncture groups, 10 rats in each subgroup. Two acupuncture groups were treated with acupuncture at four time points (1 h, 3 h, 6 h and 12 h after ischemia reperfusion), and "Shuigou" (GV 26) and "Neiguan" (PC 6) were selected in regaining consciousness group, and the non-acupoints below the bilateral costal region were selected in non-acupoint group. At the corresponding time point, the tissues of the brain were removed and interleukin1 receptor (IL-1RI) and tumor necrosis factor receptor (TNFR-I) mRNA and protein changes were detected by using real-time quantitative polymerase chain reaction and immunoblot assay. The expression of IL-1RI and TNFR-I mRNA and protein in the model group were significantly higher than that in normal group, sham operation group, regaining consciousness group and non-acupoint group (PAcupuncture can reduce the expression of IL-1RI and TNFR-I mRNA and protein in rats with cerebral ischemia reperfusion, inhibit the excessive expression of proinflammatory cytokine receptor, block apoptosis signal transduction and extend time window for treatment of cerebral ischemia, so as to play the protective effect for brain. Within 3 h of ischemia is the best time for intervention of acupuncture treatment.

  3. Role of TNF-alpha and its receptors in pericoronitis.

    Science.gov (United States)

    Beklen, A; Laine, M; Ventä, I; Hyrkäs, T; Konttinen, Y T

    2005-12-01

    The classic stimulus for cellular cytokine production is bacterial lipopolysaccharide (endotoxin). It was therefore hypothesized that tumor necrosis factor-alpha (TNF-alpha) may be responsible for pericoronitis. TNF-alpha and its receptors were detected by immunohistochemical staining in third molar pericoronitis in ten patients and ten healthy control samples. The percentage of TNF-alpha positive cells was high in pericoronitis (p = 0.0317). TNF receptors TNF-R1 and TNF-R2 were found in macrophage- and fibroblast-like cells, vascular endothelial cells in post-capillary venules, and basal epithelial cells in pericoronitis, but were only weakly expressed in controls. Increased expression of interleukin-1beta and vascular cell adhesion molecule-1 was found as a biological indicator of TNF-alpha ligand-receptor interaction. Explanted tissues acquired destructive potential upon TNF-alpha stimulation, whereas TNF-alpha blockers controlled it in inflamed tissues. These findings suggest that, in pericoronitis, inflammatory and resident cells produce and respond to potent pro-inflammatory cytokine TNF-alpha, with pathogenic and potential therapeutic relevance.

  4. Advances in Variations of Estrogen Receptor, Progesterone Receptor and Human Epidermal Growth Factor Receptor-2 Status in Metastatic Breast Cancer

    Institute of Scientific and Technical Information of China (English)

    Yuan Yuan; Zhang Lili

    2013-01-01

    Chemotherapy, endocrine therapy and molecular targeted therapy are vital means in the treatment of metastatic breast cancer (MBC), whose reasonable and standard applications are of great importance to prolong patients’ survival and improve the quality of life. The expressions of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER-2) present signiifcant differences between primary and metastatic breast cancer. However, these differences may affect the selection of MBC patients for therapeutic strategies and judgment on the prognosis. Hence, the relevant researches on variations of hormone receptors and HER-2 in primary and metastatic breast cancer, discordant causes of ER, PR and HER-2 expression in primary and metastatic lesions and clinical value of biopsy to the metastases are reviewed in the study.

  5. Signal transduction by growth factor receptors: signaling in an instant

    DEFF Research Database (Denmark)

    Dengjel, Joern; Akimov, Vyacheslav; Blagoev, Blagoy;

    2007-01-01

    -out by mass spectrometry-based proteomics has allowed exciting views on the very early events in signal transduction. Activation profiles of regulated phosphorylation sites on epidermal growth factor receptor and downstream signal transducers showed different kinetics within the first ten seconds...

  6. The epidermal growth factor receptor pathway in chronic kidney diseases

    NARCIS (Netherlands)

    Harskamp, Laura R.; Gansevoort, Ron T.; Goor, van Harry; Meijer, Esther

    2016-01-01

    The epidermal growth factor receptor (EGFR) pathway has a critical role in renal development, tissue repair and electrolyte handling. Numerous studies have reported an association between dysregulation of this pathway and the initiation and progression of various chronic kidney diseases such as diab

  7. Epidermal growth factor receptor: Target for delivery and silencing

    NARCIS (Netherlands)

    Santos Oliveira, S.

    2008-01-01

    Epidermal growth factor receptor in cancer therapy Recently, cancer research has been able to identify molecular targets that are specific for (or highly expressed by) cancer cells. These molecular targets serve as models for the development of rationally designed anticancer drugs that target import

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

    Science.gov (United States)

    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.

  9. Targeting the epidermal growth factor receptor in solid tumor malignancies

    DEFF Research Database (Denmark)

    Nedergaard, Mette K; Hedegaard, Chris J; Poulsen, Hans S

    2012-01-01

    The epidermal growth factor receptor (EGFR) is over-expressed, as well as mutated, in many types of cancers. In particular, the EGFR variant type III mutant (EGFRvIII) has attracted much attention as it is frequently and exclusively found on many tumor cells, and hence both EGFR and EGFRvIII have...... been proposed as valid targets in many cancer therapy settings. Different strategies have been developed in order to either inhibit EGFR/EGFRvIII activity or to ablate EGFR/EGFRvIII-positive tumor cells. Drugs that inhibit these receptors include monoclonal antibodies (mAbs) that bind...

  10. 注射用重组人Ⅱ型肿瘤坏死因子受体-抗体融合蛋白治疗前后中轴型脊柱关节炎患者血清白细胞介素-23水平和骶髂关节磁共振成像的变化%Change of serum interleukin-23 levels and sacroiliac joint magnetic resonance imaging before and after treatment with recombinant human tumor necrosis factorreceptor Ⅱ IgG Fc fusion protein for injection in axial spondyloarthritis patients

    Institute of Scientific and Technical Information of China (English)

    苏培培; 米存东; 赵铖; 陈战瑞; 覃芳

    2015-01-01

    Objective We investigated interleukin (IL)-23 that might play a role in the pathogenesis of rheumatoid arthritis (RA) and whether it was correlated with disease activity and clinical manifestations in axial spondyloarthritis (SPA).In addition, the Spondyloarthritis Research Consortium of Canada (SPARCC) scores was used to examine whether recombinant human tumor necrosis factorreceptor Ⅱ IgG Fc fusion protein for injection (rhTNFR:Fc) was effective for the reduction of magnetic resonance imaging (MRI)-proven sacroiliac joint (SIJ) inflammation.Methods The serum IL-23 levels of etanercept and conven-tional treatment groups were measured using enzyme-linked immunosorbent assay kits.At the same time, SIJ MRI SPARCC score levels were assessed by MRI, the change of clinical indicators of patients was observed.ANOVA, repeated measure data of ANOVA and Spearman's correlation analysis were used for statisical analysis.Results ① The basal serum IL-23 levels of the Etanercept group were (34.2±1.8) pg/ml and those of the conventional treatment group were (34.1 ±1.8) pg/ml (F=1 073.790, P=0.991), both were significantly higher than the healthy control group (18.1±0.8) pg/ml (P=0.005).After treatment, serum IL-23 levels of the rhTNFR: Fc treatment and conventional treatment group were (24.5 ±1.7) pg/ml and (25.2±1.7) pg/ml (F=232.488, P=0.242), (19.2±0.8) pg/ml and (21.6±1.3) pg/ml (F=114.135, P=0.025), (19.0±0.8) pg/ml and(19.4± 0.8) pg/ml (F=23.374, P=0.085) respectively.A significant decrease was observed in the two groups and the serum level of IL-23 of the rhTNFR:Fc group was lower than that of the conventional group at week 12.② SIJ MRI SPARCC scores of the rhTNFR:Fc group and the conventional drugs group were (20.1± 1.2) scores and(20.7±1.5) scores (F=2003.660, P=0.191), (12.5± 0.8) scores and (15.4±0.9) scores (F=1 680.430, P=0.004), (8.8±0.9) scores and (12.8± 0.9) scores (F=972.877, P=0.002), the scores of two group were significantly decreased

  11. Epidermal growth factor receptor expression in urinary bladder cancer

    Directory of Open Access Journals (Sweden)

    Dayalu S.L. Naik

    2011-01-01

    Full Text Available Objective : To evaluate the expression pattern of epidermal growth factor receptor (EGFR in urinary bladder cancer and its association with human epidermal growth factor receptor 2 (HER2, epidermal growth factor (EGF, interleukin-6 (IL-6, and high risk human papilloma virus (HPV types 16 and 18. Materials and Methods : Thirty cases of urothelial carcinoma were analyzed. EGFR, HER2, EGF, and IL-6 expressions in the tissue were evaluated by immunohistochemical staining. For HPV, DNA from tissue samples was extracted and detection of HPV was done by PCR technique. Furthermore, evaluation of different intracellular molecules associated with EGFR signaling pathways was performed by the western blot method using lysates from various cells and tissues. Results : In this study, the frequencies of immunopositivity for EGFR, HER2, EGF, and IL-6 were 23%, 60%, 47%, and 80%, respectively. No cases were positive for HPV-18, whereas HPV-16 was detected in 10% cases. Overall, expression of EGFR did not show any statistically significant association with the studied parameters. However, among male patients, a significant association was found only between EGFR and HER2. Conclusions : Overexpression of EGFR and/or HER2, two important members of the same family of growth factor receptors, was observed in a considerable proportion of cases. Precise knowledge in this subject would be helpful to formulate a rational treatment strategy in patients with urinary bladder cancer.

  12. Impaired Th1 immunity in ovarian cancer patients is mediated by TNFR2+ Tregs within the tumor microenvironment.

    Science.gov (United States)

    Govindaraj, Chindu; Scalzo-Inguanti, Karen; Madondo, Mutsa; Hallo, Julene; Flanagan, Katie; Quinn, Michael; Plebanski, Magdalena

    2013-10-01

    Ovarian cancer is a prevalent gynecological malignancy with potent immune-suppression capabilities; regulatory T cells (Tregs) are significant contributors to this immune-suppression. As ovarian cancer patients present with high levels of TNF and Tregs expressing TNFR2 are associated with maximal suppressive capacity, we investigated TNFR2+ Tregs within these patients. Indeed, TNFR2+ Tregs from tumor-associated ascites were the most potent suppressor T cell fraction. They were abundantly present within the ascites and more suppressive than peripheral blood TNFR2+ Tregs in patients. The increased suppressive capacity can be explained by a distinct cell surface expression profile, which includes high levels of CD39, CD73, TGF-β and GARP. Additionally, CD73 expression level on TNFR2+ Tregs was inversely correlated with IFN-γ production by effector T cells. This Treg fraction can be selectively recruited into the ascites from the peripheral blood of patients. Targeting TNFR2+ Tregs may offer new approaches to enhance the poor survival rates of ovarian cancer.

  13. Diverging mechanisms for TNF-alpha receptors in normal mouse brains and in functional recovery after injury: From gene to behavior

    DEFF Research Database (Denmark)

    Quintana, Albert; Molinero, Amalia; Florit, Sergi;

    2007-01-01

    insight on their role by using animals lacking either Type 1 receptor (TNFR1KO) or Type 2 (TNFR2KO) and their controls (C57Bl/6). Both TNFR1KO and to a greater extent TNFR2KO mice showed increased exploration/activity neurobehavioral traits in the hole board test, such as rearings, head dippings...... to the somatosensorial cortex. The effect of the cryolesion on motor function was evaluated with the horizontal ladder beam test, and the results showed that both TNFR1KO and TNFR2KO mice made fewer errors, suggesting a detrimental role for TNFR1/TNFR2 signaling for coping with brain damage. Expression of approximately...... 22600 genes was analyzed using an Affymetrix chip (MOE430A) at 0 (unlesioned), 1, or 4 days post-lesion in the three strains. The results show a unique and major role of both TNF receptors on the pattern of gene expression elicited by the injury but also in normal conditions, and suggest that blocking...

  14. Nuclear transportation of exogenous epidermal growth factor receptor and androgen receptor via extracellular vesicles.

    Science.gov (United States)

    Read, Jolene; Ingram, Alistair; Al Saleh, Hassan A; Platko, Khrystyna; Gabriel, Kathleen; Kapoor, Anil; Pinthus, Jehonathan; Majeed, Fadwa; Qureshi, Talha; Al-Nedawi, Khalid

    2017-01-01

    Epidermal growth factor receptor (EGFR) plays a central role in the progression of several human malignancies. Although EGFR is a membrane receptor, it undergoes nuclear translocation, where it has a distinct signalling pathway. Herein, we report a novel mechanism by which cancer cells can directly transport EGFR to the nucleus of other cells via extracellular vesicles (EVs). The transported receptor is active and stimulates the nuclear EGFR pathways. Interestingly, the translocation of EGFR via EVs occurs independently of the nuclear localisation sequence that is required for nuclear translocation of endogenous EGFR. Also, we found that the mutant receptor EGFRvIII could be transported to the nucleus of other cells via EVs. To assess the role of EVs in the regulation of an actual nuclear receptor, we studied the regulation of androgen receptor (AR). We found that full-length AR and mutant variant ARv7 are secreted in EVs derived from prostate cancer cell lines and could be transported to the nucleus of AR-null cells. The EV-derived AR was able to bind the androgen-responsive promoter region of prostate specific antigen, and recruit RNA Pol II, an indication of active transcription. The nuclear-translocated AR via EVs enhanced the proliferation of acceptor cells in the absence of androgen. Finally, we provide evidence that nuclear localisation of AR could occur in vivo via orthotopically-injected EVs in male SCID mice prostate glands. To our knowledge, this is the first study showing the nuclear translocation of nuclear receptors via EVs, which significantly extends the role of EVs as paracrine transcriptional regulators.

  15. Decreased expression of serum and microvascular vascular endothelial growth factor receptor-2 in meningococcal sepsis*.

    NARCIS (Netherlands)

    Flier, M. van der; Baerveldt, E.M.; Miedema, A.; Hartwig, N.G.; Hazelzet, J.A.; Emonts, M.; Groot, R. de; Prens, E.P.; Vught, A.J. van; Jansen, N.J.

    2013-01-01

    OBJECTIVES: To determine the skin microvessel expression of vascular endothelial growth factor receptor 2 and serum-soluble vascular endothelial growth factor receptor 2 levels in children with meningococcal sepsis. DESIGN: Observational study. SETTING: Two tertiary academic children hospital PICUs.

  16. Targeting Extracellular Domains D4 and D7 of Vascular Endothelial Growth Factor Receptor 2 Reveals Allosteric Receptor Regulatory Sites

    OpenAIRE

    Hyde, Caroline A. C.; Giese, Alexandra; Stuttfeld, Edward; Abram Saliba, Johan; Villemagne, Denis; Schleier, Thomas; Binz, H. Kaspar; Ballmer-Hofer, Kurt

    2012-01-01

    Vascular endothelial growth factors (VEGFs) activate three receptor tyrosine kinases, VEGFR-1, -2, and -3, which regulate angiogenic and lymphangiogenic signaling. VEGFR-2 is the most prominent receptor in angiogenic signaling by VEGF ligands. The extracellular part of VEGF receptors consists of seven immunoglobulin homology domains (Ig domains). Earlier studies showed that domains 2 and 3 (D23) mediate ligand binding, while structural analysis of dimeric ligand/receptor complexes by electron...

  17. Effect of Tumor Necrosis Factor-α on Neutralization of Ventricular Fibrillation in Rats with Acute Myocardial Infarction

    Directory of Open Access Journals (Sweden)

    Yu Chen

    2011-01-01

    Full Text Available The purpose of this study was to explore the effects of tumor necrosis factor-α (TNF-α on ventricular fibrillation (VF in rats with acute myocardial infarction (AMI. Rats were randomly classified into AMI group, sham operation group and recombinant human tumor necrosis factor receptor:Fc fusion protein (rhTNFR:Fc group. Spontaneous and induced VFs were recorded. Monophasic action potentials (MAPs among different zones of myocardium were recorded at eight time points before and after ligation and MAP duration dispersions (MAPDds were calculated. Then expression of TNF-α among different myocardial zones was detected. After ligation of the left anterior descending coronary artery, total TNF-α expression in AMI group began to markedly increase at 10 min, reached a climax at 20–30min, and then gradually decreased. The time-windows of VFs and MAPDds in the border zone performed in a similar way. At the same time-point, the expression of TNF-α in the ischemia zone was greater than that in the border zone, and little in the non-ischemia zone. Although the time windows of TNF-α expression, the MAPDds in the border zone and the occurrence of VFs in the rhTNFR:Fc group were similar to those in the AMI group, they all decreased in the rhTNFR:Fc group. Our findings demonstrate that TNF-α could enlarge the MAPDds in the border zone, and promote the onset of VFs.

  18. Tumor Necrosis Factor Induces Developmental Stage-Dependent Structural Changes in the Immature Small Intestine

    Directory of Open Access Journals (Sweden)

    Kathryn S. Brown

    2014-01-01

    Full Text Available Background. Premature infants are commonly subject to intestinal inflammation. Since the human small intestine does not reach maturity until term gestation, premature infants have a unique challenge, as either acute or chronic inflammation may alter the normal development of the intestinal tract. Tumor necrosis factor (TNF has been shown to acutely alter goblet cell numbers and villus length in adult mice. In this study we tested the effects of TNF on villus architecture and epithelial cells at different stages of development of the immature small intestine. Methods. To examine the effects of TNF-induced inflammation, we injected acute, brief, or chronic exposures of TNF in neonatal and juvenile mice. Results. TNF induced significant villus blunting through a TNF receptor-1 (TNFR1 mediated mechanism, leading to loss of villus area. This response to TNFR1 signaling was altered during intestinal development, despite constant TNFR1 protein expression. Acute TNF-mediated signaling also significantly decreased Paneth cells. Conclusions. Taken together, the morphologic changes caused by TNF provide insight as to the effects of inflammation on the developing intestinal tract. Additionally, they suggest a mechanism which, coupled with an immature immune system, may help to explain the unique susceptibility of the immature intestine to inflammatory diseases such as NEC.

  19. Beclin 1 regulates growth factor receptor signaling in breast cancer.

    Science.gov (United States)

    Rohatgi, R A; Janusis, J; Leonard, D; Bellvé, K D; Fogarty, K E; Baehrecke, E H; Corvera, S; Shaw, L M

    2015-10-16

    Beclin 1 is a haploinsufficient tumor suppressor that is decreased in many human tumors. The function of beclin 1 in cancer has been attributed primarily to its role in the degradative process of macroautophagy. However, beclin 1 is a core component of the vacuolar protein sorting 34 (Vps34)/class III phosphatidylinositoI-3 kinase (PI3KC3) and Vps15/p150 complex that regulates multiple membrane-trafficking events. In the current study, we describe an alternative mechanism of action for beclin 1 in breast cancer involving its control of growth factor receptor signaling. We identify a specific stage of early endosome maturation that is regulated by beclin 1, the transition of APPL1-containing phosphatidyIinositol 3-phosphate-negative (PI3P(-)) endosomes to PI3P(+) endosomes. Beclin 1 regulates PI3P production in response to growth factor stimulation to control the residency time of growth factor receptors in the PI3P(-)/APPL(+)-signaling-competent compartment. As a result, suppression of BECN1 sustains growth factor-stimulated AKT and ERK activation resulting in increased breast carcinoma cell invasion. In human breast tumors, beclin 1 expression is inversely correlated with AKT and ERK phosphorylation. Our data identify a novel role for beclin 1 in regulating growth factor signaling and reveal a mechanism by which loss of beclin 1 expression would enhance breast cancer progression.

  20. Cheiradone: a vascular endothelial cell growth factor receptor antagonist

    Directory of Open Access Journals (Sweden)

    Ahmed Nessar

    2008-01-01

    Full Text Available Abstract Background Angiogenesis, the growth of new blood vessels from the pre-existing vasculature is associated with physiological (for example wound healing and pathological conditions (tumour development. Vascular endothelial growth factor (VEGF, fibroblast growth factor-2 (FGF-2 and epidermal growth factor (EGF are the major angiogenic regulators. We have identified a natural product (cheiradone isolated from a Euphorbia species which inhibited in vivo and in vitro VEGF- stimulated angiogenesis but had no effect on FGF-2 or EGF activity. Two primary cultures, bovine aortic and human dermal endothelial cells were used in in vitro (proliferation, wound healing, invasion in Matrigel and tube formation and in vivo (the chick chorioallantoic membrane models of angiogenesis in the presence of growth factors and cheiradone. In all cases, the concentration of cheiradone which caused 50% inhibition (IC50 was determined. The effect of cheiradone on the binding of growth factors to their receptors was also investigated. Results Cheiradone inhibited all stages of VEGF-induced angiogenesis with IC50 values in the range 5.20–7.50 μM but did not inhibit FGF-2 or EGF-induced angiogenesis. It also inhibited VEGF binding to VEGF receptor-1 and 2 with IC50 values of 2.9 and 0.61 μM respectively. Conclusion Cheiradone inhibited VEGF-induced angiogenesis by binding to VEGF receptors -1 and -2 and may be a useful investigative tool to study the specific contribution of VEGF to angiogenesis and may have therapeutic potential.

  1. Upregulation of epidermal growth factor receptor 4 in ora leukoplakia

    Institute of Scientific and Technical Information of China (English)

    Hiroshi Kobayashi; Kenichi Kumagai; Akito Gotoh; Takanori Eguchi; Hiroyuki Yamada; Yoshiki Hamada; Satsuki Suzuki; Ryuji Suzuki

    2013-01-01

    In the present study, we investigate the expression profile of the epidermal growth factor receptor family, which comprises EGFR/ ErbB 1, HER2/ErbB2, HER3/ErbB3 and HER4/ErbB4 in oral leukoplakia (LP), The expression of four epidermal growth factor receptor (EGFR) family genes and their ligands were measured in LP tissues from 14 patients and compared with levels in 10 patients with oral lichen planus (OLP) and normal oral mucosa (NOM) from 14 healthy donors by real-time polymerase chain reaction (PCR) and immunohistochemistry. Synchronous mRNA coexpression of ErbB1, ErbB2, ErbB3 and ErbB4 was detected in LP lesions. Out of the receptors, only ErbB4 mRNA and protein was more highly expressed in LP compared with NOM tissues. These were strongly expressed by epithelial keratinocytes in LP lesions, as shown by immunohistochemistry. Regarding the ligands, the mRNA of Neuregulin2 and 4 were more highly expressed in OLP compared with NOM tissues. Therefore, enhanced ErbB4 on the keratinocytes and synchronous modulation of EGFR family genes may contribute to the pathogenesis and carcinogenesis of LP.

  2. Multiple autophosphorylation sites of the epidermal growth factor receptor are essential for receptor kinase activity and internalization. Contrasting significance of tyrosine 992 in the native and truncated receptors

    DEFF Research Database (Denmark)

    Sorkin, A; Helin, K; Waters, C M

    1992-01-01

    The role of epidermal growth factor (EGF) receptor autophosphorylation sites in the regulation of receptor functions has been studied using cells transfected with mutant EGF receptors. Simultaneous point mutation of 4 tyrosines (Y1068, Y1086, Y1148, Y1173) to phenylalanine, as well as removal of ...

  3. Topography of human placental receptors for epidermal growth factor.

    Science.gov (United States)

    Rao, C V; Ramani, N; Chegini, N; Stadig, B K; Carman, F R; Woost, P G; Schultz, G S; Cook, C L

    1985-02-10

    These studies were undertaken to determine whether term human placental microvillus plasma membranes, which are exposed to maternal blood, and basolateral plasma membranes, which are in close proximity to fetal blood capillaries, contain receptors for epidermal growth factor (EGF). These two highly purified membranes bound 125I-EGF with similar affinity (apparent dissociation constants, 0.07-0.12 nM, but the total number of available receptors was greater in microvillus (8.2 pmol/mg protein) compared to basolateral (4.9 pmol/mg protein) plasma membranes. Detailed characterization of 125I-EGF binding to these membranes revealed numerous similarities as well as differences. The two membranes contained two major (155 and 140 kDa) and at least three minor (115, 175, and 210 kDa) specific 125I-EGF binding proteins. The 115-kDa protein was only found in basolateral plasma membranes. The 155-kDa protein was predominantly labeled in microvillus, whereas the 140-kDa protein was labeled predominantly in basolateral plasma membranes. The addition of protease inhibitors did not alter the multiple 125I-EGF binding proteins pattern found in these membranes. EGF stimulated phosphorylation of 140- and 155-kDa proteins in both microvillus and basolateral plasma membranes. However, the 155-kDa protein was phosphorylated to a greater extent in microvillus, whereas both 140- and 155-kDa proteins were phosphorylated equally in basolateral plasma membranes. Light and electron microscope autoradiographic studies revealed that 125I-EGF preferentially associated with microvillus plasma membranes. The data demonstrates the presence of EGF receptors in outer cell membranes of syncytiotrophoblasts and suggests that maternal EGF may influence syncytiotrophoblast function by binding to receptors in microvillus plasma membranes, while fetal EGF may also influence syncytiotrophoblast function but via receptors in basolateral plasma membranes.

  4. Epidermal Growth Factor Receptor (EGFR) Crosstalks in Liver Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Berasain, Carmen, E-mail: cberasain@unav.es; Latasa, María Ujue; Urtasun, Raquel; Goñi, Saioa; Elizalde, María; Garcia-Irigoyen, Oihane; Azcona, María [Division of Hepatology and Gene Therapy, CIMA, University of Navarra, Pamplona 31008 (Spain); Prieto, Jesús [Division of Hepatology and Gene Therapy, CIMA, University of Navarra, Pamplona 31008 (Spain); CIBERehd, University Clinic, University of Navarra, Pamplona 31080 (Spain); Ávila, Matías A. [Division of Hepatology and Gene Therapy, CIMA, University of Navarra, Pamplona 31008 (Spain)

    2011-05-18

    Hepatocarcinogenesis is a complex multistep process in which many different molecular pathways have been implicated. Hepatocellular carcinoma (HCC) is refractory to conventional chemotherapeutic agents, and the new targeted therapies are meeting with limited success. Interreceptor crosstalk and the positive feedback between different signaling systems are emerging as mechanisms of targeted therapy resistance. The identification of such interactions is therefore of particular relevance to improve therapeutic efficacy. Among the different signaling pathways activated in hepatocarcinogenesis the epidermal growth factor receptor (EGFR) system plays a prominent role, being recognized as a “signaling hub” where different extracellular growth and survival signals converge. EGFR can be transactivated in response to multiple heterologous ligands through the physical interaction with multiple receptors, the activity of intracellular kinases or the shedding of EGFR-ligands. In this article we review the crosstalk between the EGFR and other signaling pathways that could be relevant to liver cancer development and treatment.

  5. Redox-dependent regulation of epidermal growth factor receptor signaling

    Directory of Open Access Journals (Sweden)

    David E. Heppner

    2016-08-01

    Full Text Available Tyrosine phosphorylation-dependent cell signaling represents a unique feature of multicellular organisms, and is important in regulation of cell differentiation and specialized cell functions. Multicellular organisms also contain a diverse family of NADPH oxidases (NOXs that have been closely linked with tyrosine kinase-based cell signaling and regulate tyrosine phosphorylation via reversible oxidation of cysteine residues that are highly conserved within many proteins involved in this signaling pathway. An example of redox-regulated tyrosine kinase signaling involves the epidermal growth factor receptor (EGFR, a widely studied receptor system with diverse functions in normal cell biology as well as pathologies associated with oxidative stress such as cancer. The purpose of this Graphical Redox Review is to highlight recently emerged concepts with respect to NOX-dependent regulation of this important signaling pathway.

  6. Circulating TNF receptors 1 and 2 are associated with the severity of renal interstitial fibrosis in IgA nephropathy.

    Directory of Open Access Journals (Sweden)

    Yuji Sonoda

    Full Text Available The current study aimed to examine whether the levels of TNF receptors 1 and 2 (TNFR1 and TNFR2 in serum and urine were associated with other markers of kidney injury and renal histological findings, including TNFR expression, in IgA nephropathy (IgAN. The levels of the parameters of interest were measured by immunoassay in 106 biopsy-proven IgAN patients using samples obtained immediately before renal biopsy and in 34 healthy subjects. Renal histological findings were evaluated using immunohistochemistry. The levels of serum TNFRs were higher in IgAN patients than in healthy subjects. The levels of both TNFRs in serum or urine were strongly correlated with each other (r > 0.9. Serum TNFR levels were positively correlated with the urinary protein to creatinine ratio (UPCR and four markers of tubular damage of interest (N-acetyl-β-D-glucosaminidase [NAG], β2 microglobulin [β2m], liver-type fatty acid-binding protein [L-FABP], and kidney injury molecule-1 [KIM-1] and negatively correlated with estimated glomerular filtration rate (eGFR. Patients in the highest tertile of serum TNFR levels showed more severe renal interstitial fibrosis than did those in the lowest or second tertiles. The tubulointerstitial TNFR2-, but not TNFR1-, positive area was significantly correlated with the serum levels of TNFRs and eGFR. Stepwise multiple regression analysis revealed that elevated serum TNFR1 or TNFR2 levels were a significant determinant of renal interstitial fibrosis after adjusting for eGFR, UPCR, and other markers of tubular damage. In conclusion, elevated serum TNFR levels were significantly associated with the severity of renal interstitial fibrosis in IgAN patients. However, the source of TNFRs in serum and urine remains unclear.

  7. EXPRESSION OF GROWTH-FACTORS AND GROWTH-FACTOR RECEPTORS IN NORMAL AND TUMOROUS HUMAN THYROID TISSUES

    NARCIS (Netherlands)

    van der Laan, B.F.A.M.; FREEMAN, JL; ASA, SL

    1995-01-01

    A number of growth factors have been implicated as stimuli of thyroid cell proliferation; overexpression of these growth factors and/or their receptors may play a role in the growth of thyroid tumors. To determine if immunohistochemical detection of growth factors and/or their receptors correlates w

  8. Clinical significance of TNF-a and sTNFR Ⅰ in forecasting infectious associated preterm labor%检测肿瘤坏死因子及可溶性肿瘤坏死因子受体Ⅰ在预测孕妇发生感染性早产的临床意义

    Institute of Scientific and Technical Information of China (English)

    马美芬; 陈伟彬

    2012-01-01

    OBJECTIVE To study the relation between tumor necrosis factor-α (TNF-α) and soluble tumor necrosis factor receptor Ⅰ (sTNFR Ⅰ) in forecasting the infectious associated preterm labor. METHODS From December 2009 to May 2011, 82 cases of preterm labors were collected and separated into two groups: infectious associated preterm labor group 37 cases, and noninfectious preterm labor group 45 cases. Another 43 cases of healthy labors were collected as the normal control group at the same time. Serum levels of TNF-α and sTNFR Ⅰ of all the cases were measured by enzyme linked immunosorbent assay (ELISA). RESULTS TNF-a of normal control group and noninfectious preterm labor group had no statistical significance (2. L±0. 3 pg/mL vs. 2. 4±1. 2 pg/mL, P> 0. 05) , but was higher in infectious associated preterm labor group (2. L±0. 3 pg/mL vs. 3. 0±0. 9 pg/mL, P< 0.05). Compared with the normal controls, sTNFR I was significantly higher in noninfectious and infectious associated preterm labor groups (3. 3±0. 6 pg/mL vs 3. 8±1. 2 pg/mL, P<0.05; 3.3±0.6 pg/mL vs. 5. 4±1. 1 pg/mL, P<0. 05). Compared with noninfectious preterm labor group, TNF-α(2. 4 ±1. 2 pg/mL vs. 3. 0±0. 9 pg/mL, P<0. 05) and sTNFR Ⅰ (3. 8±1. 2 pg/mL vs. 5. 4±1. 1 pg/mL, P<0. 05) in infectious associated preterm labor group were much higher. CONCLUSION Compared with TNF-α, sTNFR I might be a better factor in predicting infectious associated preterm labor.%目的 研究肿瘤坏死因子(TNF-α)和可溶性肿瘤坏死因子受体Ⅰ(sTNFR Ⅰ)与孕妇出现感染性早产的关系.方法 收集2009年12月-2011年5月在医院分娩的82例早产孕妇,分为早产非感染组45例和早产感染组37例,收集同期足月正常生产孕妇43例作为对照组,采用酶联免疫吸附法(ELISA)检测血清TNFα、sTNFRI的水平.结果 正常对照组的TNF-α为(2.1±0.3)pg/ml,早产非感染组的TNF-α为(2.4±1.2)pg/ml,差异无统计学意义;正常对照组

  9. Augmentation of radiation response by motesanib, a multikinase inhibitor that targets vascular endothelial growth factor receptors.

    NARCIS (Netherlands)

    Kruser, T.J.; Wheeler, D.L.; Armstrong, E.A.; Iida, M.; Kozak, K.R.; Kogel, A.J. van der; Bussink, J.; Coxon, A.; Polverino, A.; Harari, P.M.

    2010-01-01

    BACKGROUND: Motesanib is a potent inhibitor of vascular endothelial growth factor receptors (VEGFR) 1, 2, and 3, platelet-derived growth factor receptor, and Kit receptors. In this report we examine the interaction between motesanib and radiation in vitro and in head and neck squamous cell carcinoma

  10. Regulation of growth factor receptor degradation by ADP-ribosylation factor domain protein (ARD) 1.

    Science.gov (United States)

    Meza-Carmen, Victor; Pacheco-Rodriguez, Gustavo; Kang, Gi Soo; Kato, Jiro; Donati, Chiara; Zhang, Chun-Yi; Vichi, Alessandro; Payne, D Michael; El-Chemaly, Souheil; Stylianou, Mario; Moss, Joel; Vaughan, Martha

    2011-06-28

    ADP-ribosylation factor domain protein 1 (ARD1) is a 64-kDa protein containing a functional ADP-ribosylation factor (GTP hydrolase, GTPase), GTPase-activating protein, and E3 ubiquitin ligase domains. ARD1 activation by the guanine nucleotide-exchange factor cytohesin-1 was known. GTPase and E3 ligase activities of ARD1 suggest roles in protein transport and turnover. To explore this hypothesis, we used mouse embryo fibroblasts (MEFs) from ARD1-/- mice stably transfected with plasmids for inducible expression of wild-type ARD1 protein (KO-WT), or ARD1 protein with inactivating mutations in E3 ligase domain (KO-E3), or containing persistently active GTP-bound (KO-GTP), or inactive GDP-bound (KO-GDP) GTPase domains. Inhibition of proteasomal proteases in mifepristone-induced KO-WT, KO-GDP, or KO-GTP MEFs resulted in accumulation of these ARD1 proteins, whereas KO-E3 accumulated without inhibitors. All data were consistent with the conclusion that ARD1 regulates its own steady-state levels in cells by autoubiquitination. Based on reported growth factor receptor-cytohesin interactions, EGF receptor (EGFR) was investigated in induced MEFs. Amounts of cell-surface and total EGFR were higher in KO-GDP and lower in KO-GTP than in KO-WT MEFs, with levels in both mutants greater (p = 0.001) after proteasomal inhibition. Significant differences among MEF lines in content of TGF-β receptor III were similar to those in EGFR, albeit not as large. Differences in amounts of insulin receptor mirrored those in EGFR, but did not reach statistical significance. Overall, the capacity of ARD1 GTPase to cycle between active and inactive forms and its autoubiquitination both appear to be necessary for the appropriate turnover of EGFR and perhaps additional growth factor receptors.

  11. Polychlorinated Biphenyls Disrupt Hepatic Epidermal Growth Factor Receptor Signaling.

    Science.gov (United States)

    Hardesty, Josiah E; Wahlang, Banrida; Falkner, K Cameron; Clair, Heather B; Clark, Barbara J; Ceresa, Brian P; Prough, Russell A; Cave, Matthew C

    2016-07-26

    1. Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that disrupt hepatic xenobiotic and intermediary metabolism, leading to metabolic syndrome and nonalcoholic steatohepatitis (NASH). 2. Since phenobarbital indirectly activates Constitutive Androstane Receptor (CAR) by antagonizing growth factor binding to the epidermal growth factor receptor (EGFR), we hypothesised that PCBs may also diminish EGFR signaling. 3. The effects of the PCB mixture Aroclor 1260 on the protein phosphorylation cascade triggered by EGFR activation were determined in murine (in vitro and in vivo) and human models (in vitro). EGFR tyrosine residue phosphorylation was decreased by PCBs in all models tested. 4. The IC50 values for Aroclor 1260 concentrations that decreased Y1173 phosphorylation of EGFR were similar in murine AML-12 and human HepG2 cells (∼2-4 μg/mL). Both dioxin and non-dioxin-like PCB congeners decreased EGFR phosphorylation in cell culture. 5. PCB treatment reduced phosphorylation of downstream EGFR effectors including Akt and mTOR, as well as other phosphoprotein targets including STAT3 and c-RAF in vivo. 6. PCBs diminish EGFR signaling in human and murine hepatocyte models and may dysregulate critical phosphoprotein regulators of energy metabolism and nutrition, providing a new mechanism of action in environmental diseases.

  12. Serum TNF-α, sTNFR1, IL-6, IL-8 and IL-10 levels in Weil's syndrome.

    Science.gov (United States)

    Kyriakidis, Ioannis; Samara, Pinelopi; Papa, Anna

    2011-05-01

    Studies on cytokine levels in Weil's syndrome are lacking. In this study, TNF-α, sTNFR1, IL-6, IL-8 and IL-10 levels were measured in 44 serum samples of patients diagnosed with Leptospira interrogans serovar icterohaemorrhagiae infection. TNF-α levels linked with pulmonary hemorrhagic implications, while elevated sTNFR1 and IL-10 levels linked with fatal cases. IL-6 and IL-8 did not seem to affect the outcome of the disease. Immune response pattern in Weil's syndrome bears resemblance to other patterns described for hemorrhagic fevers. IL-10/TNF-α ratio is proposed as a marker for prognosis.

  13. Thyroid hormones regulate fibroblast growth factor receptor signaling during chondrogenesis.

    Science.gov (United States)

    Barnard, Joanna C; Williams, Allan J; Rabier, Bénédicte; Chassande, Olivier; Samarut, Jacques; Cheng, Sheue-Yann; Bassett, J H Duncan; Williams, Graham R

    2005-12-01

    Childhood hypothyroidism causes growth arrest with delayed ossification and growth-plate dysgenesis, whereas thyrotoxicosis accelerates ossification and growth. Thyroid hormone (T(3)) regulates chondrocyte proliferation and is essential for hypertrophic differentiation. Fibroblast growth factors (FGFs) are also important regulators of chondrocyte proliferation and differentiation, and activating mutations of FGF receptor-3 (FGFR3) cause achondroplasia. We investigated the hypothesis that T(3) regulates chondrogenesis via FGFR3 in ATDC5 cells, which undergo a defined program of chondrogenesis. ATDC5 cells expressed two FGFR1, four FGFR2, and one FGFR3 mRNA splice variants throughout chondrogenesis, and expression of each isoform was stimulated by T(3) during the first 6-12 d of culture, when T(3) inhibited proliferation by 50%. FGFR3 expression was also increased in cells treated with T(3) for 21 d, when T(3) induced an earlier onset of hypertrophic differentiation and collagen X expression. FGFR3 expression was reduced in growth plates from T(3) receptor alpha-null mice, which exhibit skeletal hypothyroidism, but was increased in T(3) receptor beta(PV/PV) mice, which display skeletal thyrotoxicosis. These findings indicate that FGFR3 is a T(3)-target gene in chondrocytes. In further experiments, T(3) enhanced FGF2 and FGF18 activation of the MAPK-signaling pathway but inhibited their activation of signal transducer and activator of transcription-1. FGF9 did not activate MAPK or signal transducer and activator of transcription-1 pathways in the absence or presence of T(3). Thus, T(3) exerted differing effects on FGFR activation during chondrogenesis depending on which FGF ligand stimulated the FGFR and which downstream signaling pathway was activated. These studies identify novel interactions between T(3) and FGFs that regulate chondrocyte proliferation and differentiation during chondrogenesis.

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

    Directory of Open Access Journals (Sweden)

    Matt Crook

    2016-11-01

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

  15. Epidermal Growth Factor Receptor in Prostate Cancer Derived Exosomes.

    Directory of Open Access Journals (Sweden)

    Geetanjali Kharmate

    Full Text Available Exosomes proteins and microRNAs have gained much attention as diagnostic tools and biomarker potential in various malignancies including prostate cancer (PCa. However, the role of exosomes and membrane-associated receptors, particularly epidermal growth factor receptor (EGFR as mediators of cell proliferation and invasion in PCa progression remains unexplored. EGFR is frequently overexpressed and has been associated with aggressive forms of PCa. While PCa cells and tissues express EGFR, it is unknown whether exosomes derived from PCa cells or PCa patient serum contains EGFR. The aim of this study was to detect and characterize EGFR in exosomes derived from PCa cells, LNCaP xenograft and PCa patient serum. Exosomes were isolated from conditioned media of different PCa cell lines; LNCaP xenograft serum as well as patient plasma/serum by differential centrifugation and ultracentrifugation on a sucrose density gradient. Exosomes were confirmed by electron microscopy, expression of exosomal markers and NanoSight™ analysis. EGFR expression was determined by western blot analysis and ELISA. This study demonstrates that exosomes may easily be derived from PCa cell lines, serum obtained from PCa xenograft bearing mice and clinical samples derived from PCa patients. Presence of exosomal EGFR in PCa patient exosomes may present a novel approach for measuring of the disease state. Our work will allow to build on this finding for future understanding of PCa exosomes and their potential role in PCa progression and as minimal invasive biomarkers for PCa.

  16. Glucocorticoids and atrial natriuretic factor receptors on vascular smooth muscle.

    Science.gov (United States)

    Yasunari, K; Kohno, M; Murakawa, K; Yokokawa, K; Takeda, T

    1990-11-01

    The effect of glucocorticoids on the atrial natriuretic factor (ANF)-mediated formation of cyclic guanosine monophosphate (cGMP) by intact vascular smooth muscle cells (VSMC) was studied in rats. Cultured VSMC were obtained from the renal arteries of 14-week-old Wistar rats by the explant method. Micromolar concentrations of dexamethasone, given as pretreatment for 48 hours, suppressed the ANF-mediated response. The dexamethasone-induced suppression was detectable at 6 hours and reached a maximum 24 hours after administration in a dose-dependent manner. Inhibitors of protein synthesis blocked this effect of the glucocorticoid. The basal activity of guanylate cyclase in the dexamethasone-treated cells was lower than in the control cells. Other steroids having glucocorticoid action mimicked this suppression of the ANF-mediated response. This suppression was blocked by a glucocorticoid receptor antagonist. The results suggest that glucocorticoids suppress ANF-mediated cGMP formation by VSMC through glucocorticoid type II receptors and the induction of protein synthesis. Suppression of the ANF-mediated response may play a role in glucocorticoid-induced hypertension.

  17. Expression of epidermal growth factor receptors in human endometrial carcinoma

    DEFF Research Database (Denmark)

    Nyholm, H C; Nielsen, Anette Lynge; Ottesen, B

    1993-01-01

    Little data exist on the expression of epidermal growth factor receptors (EGF-Rs) in human endometrial cancer. EGF-R status was studied in 65 patients with endometrial carcinomas and in 26 women with nonmalignant postmenopausal endometria, either inactive/atrophic endometrium or adenomatous...... hyperplasia. EGF-R was identified on frozen tissue sections by means of an indirect immunoperoxidase technique with a monoclonal antibody against the external domain of the EGF-R. Seventy-one percent of the carcinomas expressed positive EGF-R immunoreactivity. In general, staining was most prominent....../inactive endometria and seven of 13 (54%) endometria with adenomatous hyperplasia were EGF-R positive, with an immunostaining pattern rather similar to that of the carcinomas....

  18. Interferon gamma-dependent transactivation of epidermal growth factor receptor.

    Science.gov (United States)

    Burova, Elena; Vassilenko, Konstantin; Dorosh, Victoria; Gonchar, Ilya; Nikolsky, Nikolai

    2007-04-03

    The present report provides evidence that, in A431 cells, interferon gamma (IFNgamma) induces the rapid (within 5 min), and reversible, tyrosine phosphorylation of the epidermal growth factor receptor (EGFR). IFNgamma-induced EGFR transactivation requires EGFR kinase activity, as well as activity of the Src-family tyrosine kinases and JAK2. Here, we show that IFNgamma-induced STAT1 activation in A431 and HeLa cells partially depends on the kinase activity of both EGFR and Src. Furthermore, in these cells, EGFR kinase activity is essential for IFNgamma-induced ERK1,2 activation. This study is the first to demonstrate that EGFR is implicated in IFNgamma-dependent signaling pathways.

  19. Nod factor receptors form heteromeric complexes and are essential for intracellular infection in Medicago nodules

    NARCIS (Netherlands)

    Moling, S.; Pietraszewska-Bogiel, A.; Postma, M.; Fedorova, E.E.; Hink, M.A.; Limpens, E.H.M.; Gadella, T.W.J.; Bisseling, T.

    2014-01-01

    Rhizobial Nod factors are the key signaling molecules in the legume-rhizobium nodule symbiosis. In this study, the role of the Nod factor receptors NOD FACTOR PERCEPTION (NFP) and LYSIN MOTIF RECEPTOR-LIKE KINASE3 (LYK3) in establishing the symbiotic interface in root nodules was investigated. It wa

  20. Nod factor receptors form heteromeric complexes and are essential for intracellular infection in medicago nodules

    NARCIS (Netherlands)

    Moling, S.; Pietraszewska-Bogiel, A.; Postma, M.; Fedorova, E.; Hink, M.A.; Limpens, E.; Gadella, T.W.J.; Bisseling, T.

    2014-01-01

    Rhizobial Nod factors are the key signaling molecules in the legume-rhizobium nodule symbiosis. In this study, the role of the Nod factor receptors NOD FACTOR PERCEPTION (NFP) and LYSIN MOTIF RECEPTOR-LIKE KINASE3 (LYK3) in establishing the symbiotic interface in root nodules was investigated. It wa

  1. Study on the expression of TNFR2 in adipose tissue in PCOS%多囊卵巢综合征患者脂肪组织TNFR2的表达与其意义

    Institute of Scientific and Technical Information of China (English)

    王竹晨; 顾熊飞; 杨冬梓; 邝健全

    2004-01-01

    目的:研究多囊卵巢综合征(PCOS)患者脂肪组织肿瘤坏死因子受体II(TNFR2) mRNA的表达,探讨PCOS患者发生胰岛素抵抗(IR)的分子生物学机制.方法:用RT-PCR技术,半定量检测PCOS及其对照组脂肪组织TNFR2 mRNA的表达.结果:TNFR2 mRNA的表达在PCOS肥胖组(0.90±0.12)和PCOS非肥胖组(0.62±0.14)均显著高于非肥胖对照组(0.50±0.15),在PCOS肥胖组升高更为明显(P<0.001),PCOS肥胖组与肥胖对照组(0.88±0.14)差异无显著性(P>0.05).结论:PCOS脂肪组织TNFR2 mRNA的表达率升高,可能与PCOS患者发生IR、肥胖有关.

  2. Arctigenin induced gallbladder cancer senescence through modulating epidermal growth factor receptor pathway.

    Science.gov (United States)

    Zhang, Mingdi; Cai, Shizhong; Zuo, Bin; Gong, Wei; Tang, Zhaohui; Zhou, Di; Weng, Mingzhe; Qin, Yiyu; Wang, Shouhua; Liu, Jun; Ma, Fei; Quan, Zhiwei

    2017-05-01

    Gallbladder cancer has poor prognosis and limited therapeutic options. Arctigenin, a representative dibenzylbutyrolactone lignan, occurs in a variety of plants. However, the molecular mechanisms involved in the antitumor effect of arctigenin on gallbladder cancer have not been fully elucidated. The expression levels of epidermal growth factor receptor were examined in 100 matched pairs of gallbladder cancer tissues. A positive correlation between high epidermal growth factor receptor expression levels and poor prognosis was observed in gallbladder cancer tissues. Pharmacological inhibition or inhibition via RNA interference of epidermal growth factor receptor induced cellular senescence in gallbladder cancer cells. The antitumor effect of arctigenin on gallbladder cancer cells was primarily achieved by inducing cellular senescence. In gallbladder cancer cells treated with arctigenin, the expression level of epidermal growth factor receptor significantly decreased. The analysis of the activity of the kinases downstream of epidermal growth factor receptor revealed that the RAF-MEK-ERK signaling pathway was significantly inhibited. Furthermore, the cellular senescence induced by arctigenin could be reverted by pcDNA-epidermal growth factor receptor. Arctigenin also potently inhibited the growth of tumor xenografts, which was accompanied by the downregulation of epidermal growth factor receptor and induction of senescence. This study demonstrates arctigenin could induce cellular senescence in gallbladder cancer through the modulation of epidermal growth factor receptor pathway. These data identify epidermal growth factor receptor as a key regulator in arctigenin-induced gallbladder cancer senescence.

  3. Death receptors: Targets for cancer therapy

    Energy Technology Data Exchange (ETDEWEB)

    Mahmood, Zafar [Proteomics Laboratory, Indian Institute of Toxicology Research, Mahatma Gandhi Marg, Lucknow 226001 (India); Shukla, Yogeshwer, E-mail: yogeshwer_shukla@hotmail.com [Proteomics Laboratory, Indian Institute of Toxicology Research, Mahatma Gandhi Marg, Lucknow 226001 (India)

    2010-04-01

    Apoptosis is the cell's intrinsic program to death, which plays an important role in physiologic growth control and homeostasis. Apoptosis can be triggered by death receptors (DRs), without any adverse effects. DRs are the members of tumor necrosis factor (TNF) receptor superfamily, known to be involved in apoptosis signaling, independent of p53 tumor-supressor gene. Selective triggering of DR-mediated apoptosis in cancer cells is a novel approach in cancer therapy. So far, the best characterized DRs are CD95 (Fas/Apo1), TNF-related apoptosis-inducing ligand receptor (TRAILR) and tumor necrosis factor receptor (TNFR). Among these, TRAILR is emerging as most promising agent for cancer therapy, because it induces apoptosis in a variety of tumor and transformed cells without any toxicity to normal cells. TRAIL treatment in combination with chemotherapy or radiotherapy enhances TRAIL sensitivity or reverses TRAIL resistance by regulating downstream effectors. This review covers the current knowledge about the DRs, summarizes main signaling in DRs and also summarizes the preclinical approaches of these DRs in cancer therapy.

  4. LysM domain receptor kinases regulating rhizobial Nod factor-induced infection

    NARCIS (Netherlands)

    Limpens, E.H.M.; Franken, C.L.; Smit, P.E.J.; Willemse, J.J.; Bisseling, T.; Geurts, R.

    2003-01-01

    The rhizobial infection of legumes has the most stringent demand toward Nod factor structure of all host responses, and therefore a specific Nod factor entry receptor has been proposed. The SYM2 gene identfied in certain ecotypes of pea (Pisum sativum) is a good candidate for such an entry receptor.

  5. Fibroblast growth factor receptor 3 protein is overexpressed in oral and oropharyngeal squamous cell carcinoma

    NARCIS (Netherlands)

    Koole, Koos; van Kempen, Pauline M W; Swartz, Justin E; Peeters, Ton; van Diest, Paul J; Koole, Ron; van Es, Robert J. J.; Willems, Stefan M

    Fibroblast growth factor receptor 3 (FGFR3) is a member of the fibroblast growth factor receptor tyrosine kinase family. It has been identified as a promising therapeutic target in multiple types of cancer. We have investigated FGFR3 protein expression and FGFR3 gene copy-numbers in a single

  6. Epidermal growth factor receptor-targeted antibody therapy - Mechanisms of action and modulators of therapeutic efficacy

    NARCIS (Netherlands)

    Lammerts van Bueren, Jeroen Jilles

    2008-01-01

    Cancer is an increasing disease in the world population, and in recent years there has been substantial interest in the development of novel therapeutic agents specifically targeting growth factor receptors on tumor cells. The epidermal growth factor receptor (EGFR) represents a tyrosine kinase cell

  7. Analysis of receptor signaling pathways by mass spectrometry: identification of vav-2 as a substrate of the epidermal and platelet-derived growth factor receptors

    DEFF Research Database (Denmark)

    Pandey, A; Podtelejnikov, A V; Blagoev, B;

    2000-01-01

    Oligomerization of receptor protein tyrosine kinases such as the epidermal growth factor receptor (EGFR) by their cognate ligands leads to activation of the receptor. Transphosphorylation of the receptor subunits is followed by the recruitment of signaling molecules containing src homology 2 (SH2...

  8. Expression of epidermal growth factor receptors in human brain tumors.

    Science.gov (United States)

    Libermann, T A; Razon, N; Bartal, A D; Yarden, Y; Schlessinger, J; Soreq, H

    1984-02-01

    The expression of receptors for epidermal growth factor (EGF-R) was determined in 29 samples of brain tumors from 22 patients. Primary gliogenous tumors, of various degrees of cancer, five meningiomas, and two neuroblastomas were examined. Tissue samples were frozen in liquid nitrogen immediately after the operation and stored at -70 degrees until use. Cerebral tissue samples from 11 patients who died from diseases not related to the central nervous system served as controls. Immunoprecipitation of functional EGF-R-kinase complexes revealed high levels of EGF-R in all of the brain tumors of nonneuronal origin that were examined. The level of EGF-R varied between tumors from different patients and also between specimens prelevated from different areas of the same tumor. In contrast, the levels of EGF-R from control specimens were invariably low. The biochemical properties of EGF-R in brain tumor specimens were found to be indistinguishable from those of the well-characterized EGF-R from the A-431 cell line, derived from human epidermoid carcinomas. Human brain EGF-R displays a molecular weight of 170,000 by polyacrylamide-sodium dodecyl sulfate gel electrophoresis. It is phosphorylated mainly in tyrosine residues and shows a 2-dimensional phosphopeptide map similar to that obtained with the phosphorylated EGF-R from membranes of A-431 cells. Our observations suggest that induction of EGF-R expression may accompany the malignant transformation of human brain cells of nonneuronal origin.

  9. Indoxyl Sulfate Downregulates Mas Receptor via Aryl Hydrocarbon Receptor/Nuclear Factor-kappa B, and Induces Cell Proliferation and Tissue Factor Expression in Vascular Smooth Muscle Cells.

    Science.gov (United States)

    Ng, Hwee-Yeong; Bolati, Wulaer; Lee, Chien-Te; Chien, Yu-Shu; Yisireyili, Maimaiti; Saito, Shinichi; Pei, Sung-Nan; Nishijima, Fuyuhiko; Niwa, Toshimitsu

    2016-01-01

    Angiotensin converting enzyme-related carboxypeptidase 2/angiotensin (Ang)-(1-7)/Mas receptor axis is protective in the development of chronic kidney disease and cardiovascular disease. This study is aimed at investigating whether indoxyl sulfate (IS) affects Mas receptor expression, cell proliferation and tissue factor expression in vascular smooth muscle cells, and if Ang-(1-7), an activator of Mas receptor, counteracts the IS-induced effects. IS was administered to normotensive and hypertensive rats. Human aortic smooth muscle cells (HASMCs) were cultured with IS. IS reduced the expression of Mas receptor in the aorta of normotensive and hypertensive rats. IS downregulated the Mas receptor expression in a time- and dose-dependent manner in HASMCs. Knockdown of aryl hydrocarbon receptor (AhR) and nuclear factor-kappa B (NF-x03BA;B) inhibited IS-induced downregulation of Mas receptor. Further, IS stimulated cell proliferation and tissue factor expression in HASMCs. Ang-(1-7) attenuated IS-induced cell proliferation and tissue factor expression in HASMCs. Ang-(1-7) suppressed phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and NF-x03BA;B in HASMCs. IS downregulated the expression of Mas receptor via AhR/NF-x03BA;B, and induced cell proliferation and tissue factor expression in HASMCs. Ang-(1-7) inhibited IS-induced cell proliferation and tissue factor expression by suppressing the phosphorylation of ERK1/2 and NF-x03BA;B p65. © 2016 S. Karger AG, Basel.

  10. Tumor necrosis factor alpha inhibitors have no effect on a human T-lymphotropic virus type-I (HTLV-I)-infected cell line from patients with HTLV-I-associated myelopathy.

    Science.gov (United States)

    Fukui, Shoichi; Nakamura, Hideki; Takahashi, Yoshiko; Iwamoto, Naoki; Hasegawa, Hiroo; Yanagihara, Katsunori; Nakamura, Tatsufumi; Okayama, Akihiko; Kawakami, Atsushi

    2017-02-03

    While tumor necrosis factor alpha (TNF-α) inhibitors (TNFi) and other biologics are very effective against autoimmune diseases, they can also cause infectious diseases. Therefore, it is important to clarify whether the TNFi sometimes used to treat patients with rheumatoid arthritis (RA) complicated with human T-lymphotropic virus type-I (HTLV-I) infection have the unintended side effect of promoting HTLV-I proliferation. We used the HTLV-I-infected cell line HCT-5, derived from spinal fluid cells of a patient with HTLV-I associated myelopathy, to evaluate the production of cytokines and chemokines, TNF-α receptor (TNFR), the expression of HTLV-I associated genes, the HTLV-I proviral load (PVL), the expression of HTLV-I structural protein, and apoptosis. We used Jurkat cells as a control. Supernatants of HCT-5 showed time-dependent elevations of IL-6, RANTES and ICAM-1. HCT-5 supernatants treated with infliximab, adalimumab, etanercept (ETN), golimumab and certolizumab pegol showed no significant differences in the levels of these molecules compared to the control. Neither TNFR1 nor TNFR2 expression was altered by any TNFi treatment, relative to phosphate-buffered saline (PBS) treatment, with the exception that TNFR2 was significantly decreased and internalized in HCT-5 cells by ETN treatment. The HTLV-I associated genes Tax and HBZ and the PVL levels were not significantly changed. Immunofluorescence staining of HCT-5 for an HTLV-I-associated protein, GAG, was also not significantly different between any of the TNFi treatments and the PBS treatment. DNA ladders as an index of apoptosis were not detected. Apoptotic cells were not increased by the addition of any TNFi. In vitro, TNFi did not affect the cytokine profiles, expression of associated genes and proteins, proviral load or apoptosis of HCT-5 cells. The results suggested that TNFi treatment of RA patients complicated with HTLV-I might have no effect on HTLV-I infection.

  11. Specific antibodies and sensitive immunoassays for the human epidermal growth factor receptors (HER2, HER3, and HER4).

    Science.gov (United States)

    Broughton, Marianne Nordlund; Westgaard, Arne; Paus, Elisabeth; Øijordsbakken, Miriam; Henanger, Karoline J; Naume, Bjørn; Bjøro, Trine

    2017-06-01

    The use of trastuzumab in patients with breast cancer that overexpresses human epidermal growth factor receptor 2 has significantly improved treatment outcomes. However, a substantial proportion of this patient group still experiences progression of the disease after receiving the drug. Evaluation of the changes in expression of the human epidermal growth factor receptors could be of interest. Monoclonal antibodies against the extracellular domain of the human growth factor receptors, 2, 3, and 4, have been raised, and specific and sensitive immunoassays have been established. Sera from healthy individuals (Nordic Reference Interval Project and Database) were analyzed in the human epidermal growth factor receptor 2 assay (N = 805) and the human epidermal growth factor receptor 3 and 4 assays (N = 114), and reference limits were calculated. In addition, sera from 208 individual patients with breast cancer were tested in all three assays. Finally, the human epidermal growth factor receptor 2 assay was compared with a chemiluminescent immunoassay for serum human epidermal growth factor receptor 2/neu. Reference values were as follows: human epidermal growth factor receptor 2, human epidermal growth factor receptor 3, human epidermal growth factor receptor 4, human epidermal growth factor receptor 2 and human epidermal growth factor receptor 3 serum levels between the patients with tissue human epidermal growth factor receptor 2-positive and tissue human epidermal growth factor receptor 2-negative ( p = 0.0026, p = 0.000011) tumors, but not in the serum levels of human epidermal growth factor receptor 4 ( p = 0.054). There was good agreement between the in-house human epidermal growth factor receptor 2 assay and the chemiluminescent immunoassay. Our new specific antibodies for all the three human epidermal growth factor receptors may prove valuable in the development of novel anti-human epidermal growth factor receptor targeted therapies with

  12. Dynamic tracing for epidermal growth factor receptor mutations in urinary circulating DNA in gastric cancer patients.

    Science.gov (United States)

    Shi, Xiu-Qin; Xue, Wen-Hua; Zhao, Song-Feng; Zhang, Xiao-Jian; Sun, Wukong

    2017-02-01

    The mutations of epidermal growth factor receptor are detected in gastric cancer, indicating its suitability as a target for receptor tyrosine kinase inhibitors, as well as a marker for clinical outcome of chemotherapeutic treatments. However, extraction of quality tumor tissue for molecular processes remains challenging. Here, we aimed to examine the clinical relevance of urinary cell-free DNA as an alternative tumor material source used specifically for monitoring epidermal growth factor receptor mutations. Therefore, 120 gastric cancer patients with epidermal growth factor receptor mutations and 100 healthy controls were recruited for the study. The gastric patients also received epidermal growth factor receptor inhibitor treatment for a serial monitoring study. Paired primary tumor specimens were obtained with blood and urine samples, which were taken at a 1-month interval for a duration of 12 months. We found that urinary cell-free DNA yielded a close agreement of 92% on epidermal growth factor receptor mutation status when compared to primary tissue at baseline, and of 99% epidermal growth factor receptor mutation status when compared to plasma samples at different time points. Thus, our data suggest that urinary cell-free DNA may be a reliable source for screening and monitoring epidermal growth factor receptor mutations in the primary gastric cancer.

  13. Potent, selective inhibitors of fibroblast growth factor receptor define fibroblast growth factor dependence in preclinical cancer models.

    Science.gov (United States)

    Squires, Matthew; Ward, George; Saxty, Gordan; Berdini, Valerio; Cleasby, Anne; King, Peter; Angibaud, Patrick; Perera, Tim; Fazal, Lynsey; Ross, Douglas; Jones, Charlotte Griffiths; Madin, Andrew; Benning, Rajdeep K; Vickerstaffe, Emma; O'Brien, Alistair; Frederickson, Martyn; Reader, Michael; Hamlett, Christopher; Batey, Michael A; Rich, Sharna; Carr, Maria; Miller, Darcey; Feltell, Ruth; Thiru, Abarna; Bethell, Susanne; Devine, Lindsay A; Graham, Brent L; Pike, Andrew; Cosme, Jose; Lewis, Edward J; Freyne, Eddy; Lyons, John; Irving, Julie; Murray, Christopher; Newell, David R; Thompson, Neil T

    2011-09-01

    We describe here the identification and characterization of 2 novel inhibitors of the fibroblast growth factor receptor (FGFR) family of receptor tyrosine kinases. The compounds exhibit selective inhibition of FGFR over the closely related VEGFR2 receptor in cell lines and in vivo. The pharmacologic profile of these inhibitors was defined using a panel of human tumor cell lines characterized for specific mutations, amplifications, or translocations known to activate one of the four FGFR receptor isoforms. This pharmacology defines a profile for inhibitors that are likely to be of use in clinical settings in disease types where FGFR is shown to play an important role.

  14. Oncogenic fingerprint of epidermal growth factor receptor pathway and emerging epidermal growth factor receptor blockade resistance in colorectal cancer

    Science.gov (United States)

    Sobani, Zain A; Sawant, Ashwin; Jafri, Mikram; Correa, Amit Keith; Sahin, Ibrahim Halil

    2016-01-01

    Epidermal growth factor receptor (EGFR) has been an attractive target for treatment of epithelial cancers, including colorectal cancer (CRC). Evidence from clinical trials indicates that cetuximab and panitumumab (anti-EGFR monoclonal antibodies) have clinical activity in patients with metastatic CRC. The discovery of intrinsic EGFR blockade resistance in Kirsten RAS (KRAS)-mutant patients led to the restriction of anti-EGFR antibodies to KRAS wild-type patients by Food and Drug Administration and European Medicine Agency. Studies have since focused on the evaluation of biomarkers to identify appropriate patient populations that may benefit from EGFR blockade. Accumulating evidence suggests that patients with mutations in EGFR downstream signaling pathways including KRAS, BRAF, PIK3CA and PTEN could be intrinsically resistant to EGFR blockade. Recent whole genome studies also suggest that dynamic alterations in signaling pathways downstream of EGFR leads to distinct oncogenic signatures and subclones which might have some impact on emerging resistance in KRAS wild-type patients. While anti-EGFR monoclonal antibodies have a clear potential in the management of a subset of patients with metastatic CRC, further studies are warranted to uncover exact mechanisms related to acquired resistance to EGFR blockade. PMID:27777877

  15. Basic Fibroblast Growth Factor and Fibroblast Growth Factor Receptor-1in Human Meningiomas

    Institute of Scientific and Technical Information of China (English)

    YI Wei; CHEN Jian; Filimon H. Golwa; XUE Delin

    2005-01-01

    The expression of basic fibroblast growth factor (bFGF) and fibroblast growth factor receptor-1 (FGFR-1) in human meningiomas and the relationships between their expression and the tumors' histological features and angiogenesis were investigated by means of immunohistochemical technique. The expression of bFGF and FGFR-1 was detected by antibody of bFGF or FGFR-1.The tumors' angiogenesis was evaluated by microvascular density (MVD) and, which was observed by use of CD34-antibody immunohistochemically. The results showed that there were varied degrees of the expression of bFGF and FGFR-1 proteins in meningiomas. The expression was correlated with the tumors' histological characters and angiogenesis. It was concluded that bFGF and FGFR-1 might play important roles in meningiomas' angiogenesis and proliferation. The expression positive rate of bFGF and FGFR-1 may provide an indication of evaluating the histological and malignant degree of the tumor.

  16. Isolation of an additional member of the fibroblast growth factor receptor family, FGFR-3

    Energy Technology Data Exchange (ETDEWEB)

    Keegan, K.; Hayman, M.J. (State Univ. of New York, Stony Brook (United States)); Johnson, D.E.; Williams, L.T. (Univ. of California, San Francisco (United States))

    1991-02-15

    The fibroblast growth factors are a family of polypeptide growth factors involved in a variety of activities including mitogenesis, angiogenesis, and wound healing. Fibroblast growth factor receptors (FGFRs) have previously been identified in chicken, mouse, and human and have been shown to contain an extracellular domain with either two or three immunoglobulin-like domains, a transmembrane domain, and a cytoplasmic tyrosine kinase domain. The authors have isolated a human cDNA for another tyrosine kinase receptor that is highly homologous to the previously described FGFR. Expression of this receptor cDNA in COS cells directs the expression of a 125-kDa glycoprotein. They demonstrate that this cDNA encodes a biologically active receptor by showing that human acidic and basic fibroblast growth factors activate this receptor as measured by {sup 45}Ca{sup 2+} efflux assays. These data establish the existence of an additional member of the FGFR family that they have named FGFR-3.

  17. Phenobarbital indirectly activates the constitutive active androstane receptor (CAR) by inhibition of epidermal growth factor receptor signaling.

    Science.gov (United States)

    Mutoh, Shingo; Sobhany, Mack; Moore, Rick; Perera, Lalith; Pedersen, Lee; Sueyoshi, Tatsuya; Negishi, Masahiko

    2013-05-07

    Phenobarbital is a central nervous system depressant that also indirectly activates nuclear receptor constitutive active androstane receptor (CAR), which promotes drug and energy metabolism, as well as cell growth (and death), in the liver. We found that phenobarbital activated CAR by inhibiting epidermal growth factor receptor (EGFR) signaling. Phenobarbital bound to EGFR and potently inhibited the binding of EGF, which prevented the activation of EGFR. This abrogation of EGFR signaling induced the dephosphorylation of receptor for activated C kinase 1 (RACK1) at Tyr(52), which then promoted the dephosphorylation of CAR at Thr(38) by the catalytic core subunit of protein phosphatase 2A. The findings demonstrated that the phenobarbital-induced mechanism of CAR dephosphorylation and activation is mediated through its direct interaction with and inhibition of EGFR.

  18. Tumor necrosis factor downregulates granulocyte-colony-stimulating factor receptor expression on human acute myeloid leukemia cells and granulocytes.

    OpenAIRE

    Elbaz, O; Budel, L M; Hoogerbrugge, H; Touw, I P; Delwel, R.; Mahmoud, L A; Löwenberg, B. (Bernward)

    1991-01-01

    Tumor necrosis factor (TNF) inhibits granulocyte-colony-stimulating factor (G-CSF)-induced human acute myeloid leukemia (AML) growth in vitro. Incubation of blasts from three patients with AML in serum-free medium with TNF (10(3) U/ml), and subsequent binding studies using 125I-G-CSF reveal that TNF downregulates the numbers of G-CSF receptors by approximately 70%. G-CSF receptor numbers on purified blood granulocytes are also downmodulated by TNF. Downregulation of G-CSF receptor expression ...

  19. DEPENDENCE OF PPAR LIGAND-INDUCED MAPK SIGNALING ON EPIDERMAL GROWTH FACTOR RECEPTOR TRANSACTIVATION HEPARIN-BINDING EGF CLEAVAGE MEDIATES ZINC-INDUCED EGF RECEPTOR PHOSPHORYLATION

    Science.gov (United States)

    Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors that function as ligand-activated transcription factors regulating lipid metabolism and homeostasis. In addition to their ability to regulate PPAR-mediated gene transcription, PPARalpha and gamma li...

  20. Epidermal growth factor receptor transactivation by intracellular prostaglandin E2-activated prostaglandin E2 receptors. Role in retinoic acid receptor-β up-regulation.

    Science.gov (United States)

    Fernández-Martínez, Ana B; Lucio Cazaña, Francisco J

    2013-09-01

    The pharmacological modulation of renoprotective factor vascular endothelial growth factor-A (VEGF-A) in the proximal tubule has therapeutic interest. In human proximal tubular HK-2 cells, treatment with all-trans retinoic acid or prostaglandin E2 (PGE2) triggers the production of VEGF-A. The pathway involves an initial increase in intracellular PGE2, followed by activation of EP receptors (PGE2 receptors, most likely an intracellular subset) and increase in retinoic acid receptor-β (RARβ) expression. RARβ then up-regulates transcription factor hypoxia-inducible factor-1α (HIF-1α), which increases the transcription and production of VEGF-A. Here we studied the role in this pathway of epidermal growth factor receptor (EGFR) transactivation by EP receptors. We found that EGFR inhibitor AG1478 prevented the increase in VEGF-A production induced by PGE2- and all-trans retinoic acid. This effect was due to the inhibition of the transcriptional up-regulation of RARβ, which resulted in loss of the RARβ-dependent transcriptional up-regulation of HIF-1α. PGE2 and all-trans retinoic acid also increased EGFR phosphorylation and this effect was sensitive to antagonists of EP receptors. The role of intracellular PGE2 was indicated by two facts; i) PGE2-induced EGFR phosphorylation was substantially prevented by inhibitor of prostaglandin uptake transporter bromocresol green and ii) all-trans retinoic acid treatment, which enhanced intracellular but not extracellular PGE2, had lower effect on EGFR phosphorylation upon pre-treatment with cyclooxygenase inhibitor diclofenac. Thus, EGFR transactivation by intracellular PGE2-activated EP receptors results in the sequential activation of RARβ and HIF-1α leading to increased production of VEGF-A and it may be a target for the therapeutic modulation of HIF-1α/VEGF-A. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Evidence that the modulator of the glucocorticoid-receptor complex is the endogenous molybdate factor.

    OpenAIRE

    Bodine, P V; Litwack, G

    1988-01-01

    We have recently purified the modulator of the glucocorticoid-receptor complex from rat liver. Purified modulator inhibits glucocorticoid-receptor complex activation and stabilizes the steroid-binding ability of the unoccupied glucocorticoid receptor. Since these activities are shared by exogenous sodium molybdate, modulator appears to be the endogenous factor that sodium molybdate mimics. In this report, we present additional evidence for the mechanism of action of purified modulator. (i) Mo...

  2. T. vaginalis Infection Is Associated with Increased IL-8 and TNFr1 Levels but with the Absence of CD38 and HLADR Activation in the Cervix of ESN.

    Directory of Open Access Journals (Sweden)

    Olamide D Jarrett

    Full Text Available Trichomonas vaginalis infection is associated with an increased risk of HIV infection in exposed-seronegative women (ESN despite their unique immune quiescent profile. It is important to understand possible mechanisms, such as recruitment of activated T cells, by which T. vaginalis could facilitate HIV infection in this population.We conducted a cross-sectional study exploring the relationships between T. vaginalis infection, inflammatory markers and T cell activation in the cervix of ESN. During scheduled study visits, participants completed a behavioral questionnaire and physical exam, including sexually transmitted infection (STI screening and collection of endocervical sponge and cytobrush specimens. T cell and monocyte phenotypes were measured in cervical cytobrush specimens using multi-parameter flow cytometry. Cervical sponge specimens were used to measure cytokines (IL-6, IL-8,IL-10, IP-10, RANTES using Luminex immunoassays and the immune activation marker soluble TNF receptor 1 using ELISA.Specimens of 65 women were tested. Twenty-one of these women were infected with T. vaginalis. T. vaginalis infection was associated with significantly increased concentrations of IL-8 (1275pg/ml vs. 566pg/ml, p=.02 and sTNFr1 (430 pg/ml vs. 264 pg/ml, p=.005. However, T. vaginalis infection was not associated with increased percent expression of CCR5+ T cells nor increased CD38 and HLADR activation compared to uninfected women. It was also not associated with increased expression of CCR5+ monocytes.Among ESN T. vaginalis infection is associated with increased levels of genital pro-inflammatory/immune activation markers IL-8 and TNFr1, but was not associated with an increased percentage of activated endocervical T cells along the CD38 and HLADR pathways. Thus, while T.vaginalis infection may result in some reversal of the immune quiescent profile of ESN, enhanced recruitment of activated CD38 and HLADR expressing CD4+ cells into the endocervix may not

  3. The novel adipokine progranulin counteracts IL-1 and TLR4-driven inflammatory response in human and murine chondrocytes via TNFR1

    Science.gov (United States)

    Abella, Vanessa; Scotece, Morena; Conde, Javier; López, Verónica; Pirozzi, Claudio; Pino, Jesús; Gómez, Rodolfo; Lago, Francisca; González-Gay, Miguel Ángel; Gualillo, Oreste

    2016-01-01

    Progranulin (PGRN) is a recently identified adipokine that is supposed to have anti-inflammatory actions. The proinflammatory cytokine interleukin-1β (IL1β) stimulates several mediators of cartilage degradation. Toll like receptor-4 (TLR4) can bind to various damage-associated molecular patterns, leading to inflammatory condition. So far, no data exist of PGRN effects in inflammatory conditions induced by IL1β or lipopolysaccharide (LPS). Here, we investigated the anti-inflammatory potential of PGRN in IL1β- or LPS-induced inflammatory responses of chondrocytes. Human osteoarthritic chondrocytes and ATDC-5 cells were treated with PGRN in presence or not of IL1β or LPS. First, we showed that recombinant PGRN had no effects on cell viability. We present evidence that PGRN expression was increased during the differentiation of ATDC-5 cell line. Moreover, PGRN mRNA and protein expression is increased in cartilage, synovial and infrapatellar fat pad tissue samples from OA patients. PGRN mRNA levels are upregulated under TNFα and IL1β stimulation. Our data showed that PGRN is able to significantly counteract the IL1β-induced expression of NOS2, COX2, MMP13 and VCAM-1. LPS-induced expression of NOS2 is also decreased by PGRN. These effects are mediated, at least in part, through TNFR1. Taken together, our results suggest that PGRN has a clear anti-inflammatory function. PMID:26853108

  4. Regulation of ciliary neurotrophic factor receptor alpha in sciatic motor neurons following axotomy.

    Science.gov (United States)

    MacLennan, A J; Devlin, B K; Neitzel, K L; McLaurin, D L; Anderson, K J; Lee, N

    1999-01-01

    Spinal motor neurons are one of the few classes of neurons capable of regenerating axons following axotomy. Injury-induced expression of neurotrophic factors and corresponding receptors may play an important role in this rare ability. A wide variety of indirect data suggests that ciliary neurotrophic factor receptor alpha may critically contribute to the regeneration of injured spinal motor neurons. We used immunohistochemistry, in situ hybridization and retrograde tracing techniques to study the regulation of ciliary neurotrophic factor receptor alpha in axotomized sciatic motor neurons. Ciliary neurotrophic factor receptor alpha immunoreactivity, detected with two independent antisera, is increased in a subpopulation of caudal sciatic motor neuron soma one, two and six weeks after sciatic nerve transection and reattachment, while no changes are detected at one day and 15 weeks post-lesion. Ciliary neurotrophic factor receptor alpha messenger RNA levels are augmented in the same classes of neurons following an identical lesion, suggesting that increased synthesis contributes, at least in part, to the additional ciliary neurotrophic factor receptor alpha protein. Separating the proximal and distal nerve stumps with a plastic barrier does not noticeably affect the injury-induced change in ciliary neurotrophic factor receptor alpha regulation, thereby indicating that this injury response is not dependent on signals distal to the lesion traveling retrogradely through the nerve or signals generated by axonal growth through the distal nerve. The prolonged increases in ciliary neurotrophic factor receptor alpha protein and messenger RNA found in regenerating sciatic motor neurons contrast with the responses of non-regenerating central neurons, which are reported to display, at most, a short-lived increase in ciliary neurotrophic factor receptor alpha messenger RNA expression following injury. The present data are the first to demonstrate, in vivo, neuronal regulation of

  5. Secreted APE1/Ref-1 inhibits TNF-α-stimulated endothelial inflammation via thiol-disulfide exchange in TNF receptor.

    Science.gov (United States)

    Park, Myoung Soo; Choi, Sunga; Lee, Yu Ran; Joo, Hee Kyoung; Kang, Gun; Kim, Cuk-Seong; Kim, Soo Jin; Lee, Sang Do; Jeon, Byeong Hwa

    2016-03-11

    Apurinic apyrimidinic endonuclease 1/Redox factor-1 (APE1/Ref-1) is a multifunctional protein with redox activity and is proved to be secreted from stimulated cells. The aim of this study was to evaluate the functions of extracellular APE1/Ref-1 with respect to leading anti-inflammatory signaling in TNF-α-stimulated endothelial cells in response to acetylation. Treatment of TNF-α-stimulated endothelial cells with an inhibitor of deacetylase that causes intracellular acetylation, considerably suppressed vascular cell adhesion molecule-1 (VCAM-1). During TSA-mediated acetylation in culture, a time-dependent increase in secreted APE1/Ref-1 was confirmed. The acetyl moiety of acetylated-APE1/Ref-1 was rapidly removed based on the removal kinetics. Additionally, recombinant human (rh) APE1/Ref-1 with reducing activity induced a conformational change in rh TNF-α receptor 1 (TNFR1) by thiol-disulfide exchange. Following treatment with the neutralizing anti-APE1/Ref-1 antibody, inflammatory signals via the binding of TNF-α to TNFR1 were remarkably recovered, leading to up-regulation of reactive oxygen species generation and VCAM-1, in accordance with the activation of p66(shc) and p38 MAPK. These results strongly indicate that anti-inflammatory effects in TNF-α-stimulated endothelial cells by acetylation are tightly linked to secreted APE1/Ref-1, which inhibits TNF-α binding to TNFR1 by reductive conformational change, with suggestion as an endogenous inhibitor of vascular inflammation.

  6. LysM domain receptor kinases regulating rhizobial Nod factor-induced infection.

    Science.gov (United States)

    Limpens, Erik; Franken, Carolien; Smit, Patrick; Willemse, Joost; Bisseling, Ton; Geurts, René

    2003-10-24

    The rhizobial infection of legumes has the most stringent demand toward Nod factor structure of all host responses, and therefore a specific Nod factor entry receptor has been proposed. The SYM2 gene identified in certain ecotypes of pea (Pisum sativum) is a good candidate for such an entry receptor. We exploited the close phylogenetic relationship of pea and the model legume Medicago truncatula to identify genes specifically involved in rhizobial infection. The SYM2 orthologous region of M. truncatula contains 15 putative receptor-like genes, of which 7 are LysM domain-containing receptor-like kinases (LYKs). Using reverse genetics in M. truncatula, we show that two LYK genes are specifically involved in infection thread formation. This, as well as the properties of the LysM domains, strongly suggests that they are Nod factor entry receptors.

  7. Pinitol targets nuclear factor-kappaB activation pathway leading to inhibition of gene products associated with proliferation, apoptosis, invasion, and angiogenesis.

    Science.gov (United States)

    Sethi, Gautam; Ahn, Kwang Seok; Sung, Bokyung; Aggarwal, Bharat B

    2008-06-01

    Pinitol (3-O-methyl-chiroinositol), a component of traditional Ayurvedic medicine (talisapatra), has been shown to exhibit anti-inflammatory and antidiabetic activities through undefined mechanisms. Because the transcription factor nuclear factor-kappaB (NF-kappaB) has been linked with inflammatory diseases, including insulin resistance, we hypothesized that pinitol must mediate its effects through modulation of NF-kappaB activation pathway. We found that pinitol suppressed NF-kappaB activation induced by inflammatory stimuli and carcinogens. This suppression was not specific to cell type. Besides inducible, pinitol also abrogated constitutive NF-kappaB activation noted in most tumor cells. The suppression of NF-kappaB activation by pinitol occurred through inhibition of the activation of IkappaBalpha kinase, leading to sequential suppression of IkappaBalpha phosphorylation, IkappaBalpha degradation, p65 phosphorylation, p65 nuclear translocation, and NF-kappaB-dependent reporter gene expression. Pinitol also suppressed the NF-kappaB reporter activity induced by tumor necrosis factor receptor (TNFR)-1, TNFR-associated death domain, TNFR-associated factor-2, transforming growth factor-beta-activated kinase-1 (TAK-1)/TAK1-binding protein-1, and IkappaBalpha kinase but not that induced by p65. The inhibition of NF-kappaB activation thereby led to down-regulation of gene products involved in inflammation (cyclooxygenase-2), proliferation (cyclin D1 and c-myc), invasion (matrix metalloproteinase-9), angiogenesis (vascular endothelial growth factor), and cell survival (cIAP1, cIAP2, X-linked inhibitor apoptosis protein, Bcl-2, and Bcl-xL). Suppression of these gene products by pinitol enhanced the apoptosis induced by TNF and chemotherapeutic agents and suppressed TNF-induced cellular invasion. Our results show that pinitol inhibits the NF-kappaB activation pathway, which may explain its ability to suppress inflammatory cellular responses.

  8. Expression of growth factor receptors and targeting of EGFR in cholangiocarcinoma cell lines

    Directory of Open Access Journals (Sweden)

    Kellermeier Silvia

    2010-06-01

    Full Text Available Abstract Background Cholangiocarcinoma (CC is a malignant neoplasm of the bile ducts or the gallbladder. Targeting of growth factor receptors showed therapeutic potential in palliative settings for many solid tumors. The aim of this study was to determine the expression of seven growth factor receptors in CC cell lines and to assess the effect of blocking the EGFR receptor in vitro. Methods Expression of EGFR (epithelial growth factor receptor, HGFR (hepatocyte growth factor receptor IGF1R (insulin-like growth factor 1 receptor, IGF2R (insulin-like growth factor 2 receptor and VEGFR1-3 (vascular endothelial growth factor receptor 1-3 were examined in four human CC cell lines (EGI-1, HuH28, OZ and TFK-1. The effect of the anti-EGFR-antibody cetuximab on cell growth and apoptosis was studied and cell lines were examined for KRAS mutations. Results EGFR, HGFR and IGFR1 were present in all four cell lines tested. IGFR2 expression was confirmed in EGI-1 and TFK-1. No growth-inhibitory effect was found in EGI-1 cells after incubation with cetuximab. Cetuximab dose-dependently inhibited growth in TFK-1. Increased apoptosis was only seen in TFK-1 cells at the highest cetuximab dose tested (1 mg/ml, with no dose-response-relationship at lower concentrations. In EGI-1 a heterozygous KRAS mutation was found in codon 12 (c.35G>A; p.G12D. HuH28, OZ and TFK-1 lacked KRAS mutation. Conclusion CC cell lines express a pattern of different growth receptors in vitro. Growth factor inhibitor treatment could be affected from the KRAS genotype in CC. The expression of EGFR itself does not allow prognoses on growth inhibition by cetuximab.

  9. Sulindac metabolites inhibit epidermal growth factor receptor activation and expression

    Directory of Open Access Journals (Sweden)

    Pangburn Heather A

    2005-09-01

    Full Text Available Abstract Background Regular use of nonsteroidal anti-inflammatory drugs (NSAIDs is associated with a decreased mortality from colorectal cancer (CRC. NSAIDs induce apoptotic cell death in colon cancer cells in vitro and inhibit growth of neoplastic colonic mucosa in vivo however, the biochemical mechanisms required for these growth inhibitory effects are not well defined. We previously reported that metabolites of the NSAID sulindac downregulate extracellular-signal regulated kinase 1/2 (ERK1/2 signaling and that this effect is both necessary and sufficient for the apoptotic effects of these drugs. The goal of this project was to specifically test the hypothesis that sulindac metabolites block activation and/or expression of the epidermal growth factor (EGF receptor (EGFR. Methods HT29 human colon cancer cells were treated with EGF, alone, or in the presence of sulindac sulfide or sulindac sulfone. Cells lysates were assayed by immunoblotting for phosphorylated EGFR (pEGFR, pY1068, total EGFR, phosphorylated ERK1/2 (pERK1/2, total ERK1/2, activated caspase-3, and α-tubulin. Results EGF treatment rapidly induced phosphorylation of both EGFR and ERK1/2 in HT29 colon cancer cells. Pretreatment with sulindac metabolites for 24 h blocked EGF-induced phosphorylation of both EGFR and ERK1/2 and decreased total EGFR protein expression. Under basal conditions, downregulation of pEGFR and total EGFR was detected as early as 12 h following sulindac sulfide treatment and persisted through at least 48 h. Sulindac sulfone induced downregulation of pEGFR and total EGFR was detected as early as 1 h and 24 h, respectively, following drug treatment, and persisted through at least 72 h. EGFR downregulation by sulindac metabolites was observed in three different CRC cell lines, occurred prior to the observed downregulation of pERK1/2 and induction of apoptosis by these drugs, and was not dependent of caspase activation. Conclusion These results suggest that

  10. Neural stem cells express melatonin receptors and neurotrophic factors: colocalization of the MT1 receptor with neuronal and glial markers

    Directory of Open Access Journals (Sweden)

    McMillan Catherine R

    2004-10-01

    Full Text Available Abstract Background In order to optimize the potential benefits of neural stem cell (NSC transplantation for the treatment of neurodegenerative disorders, it is necessary to understand their biological characteristics. Although neurotrophin transduction strategies are promising, alternative approaches such as the modulation of intrinsic neurotrophin expression by NSCs, could also be beneficial. Therefore, utilizing the C17.2 neural stem cell line, we have examined the expression of selected neurotrophic factors under different in vitro conditions. In view of recent evidence suggesting a role for the pineal hormone melatonin in vertebrate development, it was also of interest to determine whether its G protein-coupled MT1 and MT2 receptors are expressed in NSCs. Results RT-PCR analysis revealed robust expression of glial cell-line derived neurotrophic factor (GDNF, brain-derived neurotrophic factor (BDNF and nerve growth factor (NGF in undifferentiated cells maintained for two days in culture. After one week, differentiating cells continued to exhibit high expression of BDNF and NGF, but GDNF expression was lower or absent, depending on the culture conditions utilized. Melatonin MT1 receptor mRNA was detected in NSCs maintained for two days in culture, but the MT2 receptor was not seen. An immature MT1 receptor of about 30 kDa was detected by western blotting in NSCs cultured for two days, whereas a mature receptor of about 40 – 45 kDa was present in cells maintained for longer periods. Immunocytochemical studies demonstrated that the MT1 receptor is expressed in both neural (β-tubulin III positive and glial (GFAP positive progenitor cells. An examination of the effects of melatonin on neurotrophin expression revealed that low physiological concentrations of this hormone caused a significant induction of GDNF mRNA expression in NSCs following treatment for 24 hours. Conclusions The phenotypic characteristics of C17.2 cells suggest that they are

  11. Expression and purification of Nod factor receptors - Initial characterization of ligand binding

    DEFF Research Database (Denmark)

    Broghammer, Angelique

    . Lipochitooligosaccharides also serve as signals in the mutually beneficial interactions between arbuscular mycorrhiza (AM) and most land plants. In the model legume Lotus japonicus the Nod factor receptors, LjNFR1 and LjNFR5, two LysM receptor like kinases (LysM-RLK), are responsible for perceiving the rhizobial...

  12. Targeting hepatocyte growth factor receptor (Met) positive tumor cells using internalizing nanobody-decorated albumin nanoparticles

    NARCIS (Netherlands)

    Heukers, Raimond|info:eu-repo/dai/nl/325788103; Altintas, Isil|info:eu-repo/dai/nl/341537160; Raghoenath, Smiriti; De Zan, Erica; Pepermans, Richard; Roovers, Rob C.|info:eu-repo/dai/nl/205435599; Haselberg, Rob|info:eu-repo/dai/nl/304822647; Hennink, Wim E.|info:eu-repo/dai/nl/070880409; Schiffelers, Raymond M.|info:eu-repo/dai/nl/212909509; Kok, Robbert J.|info:eu-repo/dai/nl/170678326; Van Bergen en Henegouwen, Paul M P|info:eu-repo/dai/nl/071919481

    2014-01-01

    The hepatocyte growth factor receptor (HGFR, c-Met or Met) is a receptor tyrosine kinase that is involved in embryogenesis, tissue regeneration and wound healing. Abnormal activation of this proto-oncogene product is implicated in the development, progression and metastasis of many cancers. Current

  13. Regulation of Epidermal Growth Factor Receptor Trafficking by Lysine Deacetylase HDAC6

    DEFF Research Database (Denmark)

    Lissanu Deribe, Yonathan; Wild, Philipp; Chandrashaker, Akhila;

    2009-01-01

    Binding of epidermal growth factor (EGF) to its receptor leads to receptor dimerization, assembly of protein complexes, and activation of signaling networks that control key cellular responses. Despite their fundamental role in cell biology, little is known about protein complexes associated...

  14. Targeting of the tumor necrosis factor receptor superfamily for cancer immunotherapy

    NARCIS (Netherlands)

    Bremer, Edwin

    2013-01-01

    The tumor necrosis factor (TNF) ligand and cognate TNF receptor superfamilies constitute an important regulatory axis that is pivotal for immune homeostasis and correct execution of immune responses. TNF ligands and receptors are involved in diverse biological processes ranging from the selective in

  15. Hierarchical classification strategy for Phenotype extraction from epidermal growth factor receptor endocytosis screening

    NARCIS (Netherlands)

    L. Cao (Lu); M. Graauw (Marjo de); K. Yan (Kuan); L.C.J. Winkel (Leah C.J.); F.J. Verbeek (Fons)

    2016-01-01

    textabstractBackground: Endocytosis is regarded as a mechanism of attenuating the epidermal growth factor receptor (EGFR) signaling and of receptor degradation. There is increasing evidence becoming available showing that breast cancer progression is associated with a defect in EGFR endocytosis. In

  16. Tumor necrosis factor receptor-associated factor 3 is a positive regulator of pathological cardiac hypertrophy.

    Science.gov (United States)

    Jiang, Xi; Deng, Ke-Qiong; Luo, Yuxuan; Jiang, Ding-Sheng; Gao, Lu; Zhang, Xiao-Fei; Zhang, Peng; Zhao, Guang-Nian; Zhu, Xueyong; Li, Hongliang

    2015-08-01

    Cardiac hypertrophy, a common early symptom of heart failure, is regulated by numerous signaling pathways. Here, we identified tumor necrosis factor receptor-associated factor 3 (TRAF3), an adaptor protein in tumor necrosis factor-related signaling cascades, as a key regulator of cardiac hypertrophy in response to pressure overload. TRAF3 expression was upregulated in hypertrophied mice hearts and failing human hearts. Four weeks after aortic banding, cardiac-specific conditional TRAF3-knockout mice exhibited significantly reduced cardiac hypertrophy, fibrosis, and dysfunction. Conversely, transgenic mice overexpressing TRAF3 in the heart developed exaggerated cardiac hypertrophy in response to pressure overload. TRAF3 also promoted an angiotensin II- or phenylephrine-induced hypertrophic response in isolated cardiomyocytes. Mechanistically, TRAF3 directly bound to TANK-binding kinase 1 (TBK1), causing increased TBK1 phosphorylation in response to hypertrophic stimuli. This interaction between TRAF3 and TBK1 further activated AKT signaling, which ultimately promoted the development of cardiac hypertrophy. Our findings not only reveal a key role of TRAF3 in regulating the hypertrophic response but also uncover TRAF3-TBK1-AKT as a novel signaling pathway in the development of cardiac hypertrophy and heart failure. This pathway may represent a potential therapeutic target for this pathological process.

  17. 成骨细胞膜脂筏在TNFR1介导信号转导中的作用%The role of lipid raft in TNFR1-media-ted signal transduction in osteoblasts

    Institute of Scientific and Technical Information of China (English)

    王海芳; Fredrick M.Pavalko; 梅其炳

    2011-01-01

    目的:初步研究细胞膜脂筏在MC3T3成骨细胞TNFRl介导信号转导中的作用.方法:应用MCD(10 g/L,60 min)消耗细胞膜胆固醇,以TNF-α(10 μg/L)刺激MC313成骨细胞0、5、10、15、30 rain或以TNF-α+CHX(10ms/L)处理4 h诱导凋亡,以SDS-PAGE/Western blot法检测IKBot、ph-AKT、ph-ERK、ph-p38及caspase-3活性片段表达水平的变化,分析膜胆固醇在TNFRI介导信号转导中的作用.结果:MCD(10 g/L)处理60 min可将膜胆固醇水平减少至约35%.降低膜胆固醇水平不影响TNFRI介导的IKBa信号,但显著抑制TNFRl介导的AKT磷酸化激活;不影响TNFRl介导的caspase03活化和细胞凋亡;也不影响TNFRI介导的ERK和p38磷酸化激活.结论:消耗膜胆固醇可破坏脂筏结构,提示成骨细胞膜脂筏在TNFR1介导AKT激活的过程中发挥重要作用,而TNFR1介导的NF-kB和ERK、p38及凋亡信号通路的激活并不依赖脂筏.%AIM: To investigate the role of membrane cholesterol in TNFR1-mediated signal transduction in osteoblastic MC3T3 cells.METHODS: MCD binds cholesterol specifically and was commonly used to deplete cholesterol from cell plasma membrane.MC3T3 cells were serumstarved for 22 h, treated with MCD ( 10 g/L) for 60 min followed by TNF-α ( 10 μg/L) for 0, 5, 10, 15 or 30 min, or TNF-α plus CHX (10 mg/L) for 4 h to induce apoptosis,then TNFR1-mediated IκBα degradation, phosphorylation of AKT, ERK or p38, and processing of caspase-3 were analyzed by using SDS-PAGE/Western blotting method.RESULTS: MC3T3 cell membrane cholesterol level was reduced to 35% within 60 min by MCD ( 10 g/L).Reduction of MC3T3 cell surface cholesterol dramatically inhibited TNFR1-mediated AKT phosphorylation, while did not affect the degradation of IκBα, activation of ERK or p38, and processing of caspase-3 induced by TNF-α.CONCLUSION: Cholesterol depletion can destruct lipid rafts; therefore our results suggest that lipid raft is essential for TNFR1-mediated AKT phosphorylation, but is

  18. Equine insulin receptor and insulin-like growth factor-1 receptor expression in digital lamellar tissue and insulin target tissues.

    Science.gov (United States)

    Kullmann, A; Weber, P S; Bishop, J B; Roux, T M; Norby, B; Burns, T A; McCutcheon, L J; Belknap, J K; Geor, R J

    2016-09-01

    Hyperinsulinaemia is implicated in the pathogenesis of endocrinopathic laminitis. Insulin can bind to different receptors: two insulin receptor isoforms (InsR-A and InsR-B), insulin-like growth factor-1 receptor (IGF-1R) and InsR/IGF-1R hybrid receptor (Hybrid). Currently, mRNA expression of these receptors in equine tissues and the influence of body type and dietary carbohydrate intake on expression of these receptors is not known. The study objectives were to characterise InsR-A, InsR-B, IGF-1R and Hybrid expression in lamellar tissue (LT) and insulin responsive tissues from horses and examine the effect of dietary nonstructural carbohydrate (NSC) on mRNA expression of these receptors in LT, skeletal muscle, liver and two adipose tissue (AT) depots of lean and obese ponies. In vivo experiment. Lamellar tissue samples were evaluated by quantitative reverse transcription polymerase chain reaction (RT-qPCR) for receptor mRNA expression (n = 8) and immunoblotting for protein expression (n = 3). Archived LT, skeletal muscle, liver and AT from lean and obese mixed-breed ponies fed either a low (~7% NSC as dry matter; 5 lean, 5 obese) or high NSC diet (~42% NSC as dry matter; 6 lean, 6 obese) for 7 days were evaluated by RT-qPCR to determine the effect of body condition and diet on expression of the receptors in different tissues. Significance was set at P≤0.05. Lamellar tissue expresses both InsR isoforms, IGF-1R and Hybrid. LT IGF-1R gene expression was greater than either InsR isoform and InsR-A expression was greater than InsR-B (P≤0.05). Obesity significantly lowered IGF-1R, InsR-A and InsR-B mRNA expression in LT and InsR-A in tailhead AT. High NSC diet lowered expression of all three receptor types in liver; IGF-1R and InsR-A in LT and InsR-A in tailhead AT. Lamellar tissue expresses IGF-1R, InsR isoforms and Hybrids. The functional characteristics of these receptors and their role in endocrinopathic laminitis warrants further investigation. © 2015 EVJ

  19. EXPRESSION OF EPIDERMAL GROWTH FACTOR, TRANSFORMING GROWTH FACTOR-a AND THEIR RECEPTOR IN HUMAN PITUITARY TUMORS

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Long

    2001-01-01

    [1]LIU Xu-wen, FU Pei-yu, GAO Zhi-xian. Expression of epidermal growth factor receptors in human glioma [J]. Chin J Neurosurgery 1998; 14:71.[2]Wong AJ, Ruppert JM, Bigner SH, et al. Structural alterations of the epidermal growth factor receptor gene in human gliomas [J]. Proc Natl Acad Sci USA 1992; 89:4309.[3]Webster J, Ham J, Bevan JS. Preliminary characterization of growth factors secreted by human pituitary tumors [J]. J Clin Endocrinol Metab 1991; 72:687.[4]Klibanski A. Nonsecreting pituitary tumors [J]. Endocrinol Metab Clin North Am 1987; 16:793.[5]LeRiche VK, Asa SL, Ezzat S. Epidermal growth factor and its receptor (EGF-R) in human pituitary adenomas: EGF-R correlates with tumor aggressiveness [J]. J Clin Endocrinol Metab 1996; 81:656.

  20. Characterization of ubiquitination dependent dynamics in growth factor receptor signaling by quantitative proteomics

    DEFF Research Database (Denmark)

    Akimov, Vyacheslav; Rigbolt, Kristoffer T G; Nielsen, Mogens M;

    2011-01-01

    ) for selectively decoding ubiquitination-driven processes involved in the regulation of cellular signaling networks. We applied this approach to characterize the temporal dynamics of ubiquitination events accompanying epidermal growth factor receptor (EGFR) signal transduction. We used recombinant UBDs derived...

  1. New factors influencing G protein coupled receptors’ system ...

    African Journals Online (AJOL)

    Abdelaziz Ghanemi

    2012-11-24

    Nov 24, 2012 ... system functions. Abdelaziz .... systems. Such factors will be added to those already known including ..... crossroad between cell biology and physics. Nat Cell ... classification of receptors for 5-hydroxytryptamine (Serotonin).

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

    Science.gov (United States)

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

    2014-03-01

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

  3. Linkage and association analysis of candidate genes for TB and TNFalpha cytokine expression: evidence for association with IFNGR1, IL-10, and TNF receptor 1 genes.

    Science.gov (United States)

    Stein, Catherine M; Zalwango, Sarah; Chiunda, Allan B; Millard, Christopher; Leontiev, Dmitry V; Horvath, Amanda L; Cartier, Kevin C; Chervenak, Keith; Boom, W Henry; Elston, Robert C; Mugerwa, Roy D; Whalen, Christopher C; Iyengar, Sudha K

    2007-07-01

    Tuberculosis (TB) is a growing public health threat globally and several studies suggest a role of host genetic susceptibility in increased TB risk. As part of a household contact study in Kampala, Uganda, we have taken a unique approach to the study of genetic susceptibility to TB by developing an intermediate phenotype model for TB susceptibility, analyzing levels of tumor necrosis factor-alpha (TNFalpha) in response to culture filtrate as the phenotype. In the present study, we analyzed candidate genes related to TNFalpha regulation and found that interleukin (IL)-10, interferon-gamma receptor 1 (IFNGR1), and TNFalpha receptor 1 (TNFR1) genes were linked and associated to both TB and TNFalpha. We also show that these associations are with progression to active disease and not susceptibility to latent infection. This is the first report of an association between TB and TNFR1 in a human population and our findings for IL-10 and IFNGR1 replicate previous findings. By observing pleiotropic effects on both phenotypes, we show construct validity of our intermediate phenotype model, which enables the characterization of the role of these genetic polymorphisms on TB pathogenesis. This study further illustrates the utility of such a model for disentangling complex traits.

  4. Histamine receptors expressed in circulating progenitor cells have reciprocal actions in ligation-induced arteriosclerosis.

    Science.gov (United States)

    Yamada, Sohsuke; Wang, Ke-Yong; Tanimoto, Akihide; Guo, Xin; Nabeshima, Atsunori; Watanabe, Takeshi; Sasaguri, Yasuyuki

    2013-09-01

    Histamine is synthesized as a low-molecular-weight amine from L-histidine by histidine decarboxylase (HDC). Recently, we demonstrated that carotid artery-ligated HDC gene-deficient mice (HDC(-/-)) showed less neointimal formation than wild-type (WT) mice, indicating that histamine participates in the process of arteriosclerosis. However, little is known about the roles of histamine-specific receptors (HHRs) in arteriosclerosis. To define the roles of HHRs in arteriosclerosis, we investigated intimal remodeling in ligated carotid arteries of HHR-deficient mice (H1R(-/-) or H2R(-/-)). Quantitative analysis showed that H1R(-/-) mice had significantly less arteriosclerogenesis, whereas H2R(-/-) mice had more, as compared with WT mice. Bone marrow transplantation from H1R(-/-) or H2R(-/-) to WT mice confirmed the above observation. Furthermore, the increased expression of monocyte chemoattractant protein (MCP-1), platelet-derived growth factor (PDGF), adhesion molecules and liver X receptor (LXR)-related inflammatory signaling factors, including Toll-like receptor (TLR3), interleukin-1 receptor (IL-1R) and tumor necrosis factor receptor (TNF-R), was consistent with the arteriosclerotic phenotype of H2R(-/-) mice. Peripheral progenitor cells in H2R(-/-) mice accelerate ligation-induced arteriosclerosis through their regulation of MCP-1, PDGF, adhesion molecules and LXR-related inflammatory signaling factors. In contrast, peripheral progenitor cells act to suppress arteriosclerosis in H1R(-/-) mice, indicating that HHRs reciprocally regulate inflammation in the ligation-induced arteriosclerosis.

  5. Specificity of human anti-variable heavy (VH ) chain autoantibodies and impact on the design and clinical testing of a VH domain antibody antagonist of tumour necrosis factorreceptor 1.

    Science.gov (United States)

    Cordy, J C; Morley, P J; Wright, T J; Birchler, M A; Lewis, A P; Emmins, R; Chen, Y Z; Powley, W M; Bareille, P J; Wilson, R; Tonkyn, J; Bayliffe, A I; Lazaar, A L

    2015-11-01

    During clinical trials of a tumour necrosis factor (TNF)-R1 domain antibody (dAb™) antagonist (GSK1995057), infusion reactions consistent with cytokine release were observed in healthy subjects with high levels of a novel, pre-existing human anti-VH (HAVH) autoantibody. In the presence of HAVH autoantibodies, GSK1995057 induced cytokine release in vitro due to binding of HAVH autoantibodies to a framework region of the dAb. The epitope on GSK1995057 was characterized and dAbs with reduced binding to HAVH autoantibodies were generated; pharmacological comparability was determined in human in-vitro systems and in-vivo animal experiments. A Phase I clinical trial was conducted to investigate the safety and tolerability of the modified dAb (GSK2862277). A significant reduction in HAVH binding was achieved by adding a single alanine residue at the C-terminus to create GSK2862277. Screening a pool of healthy donors demonstrated a reduced frequency of pre-existing autoantibodies from 51% to 7%; in all other respects, GSK2862277 and the parent dAb were comparable. In the Phase I trial, GSK2862277 was well tolerated by both the inhaled and intravenous routes. One subject experienced a mild infusion reaction with cytokine release following intravenous dosing. Subsequently, this subject was found to have high levels of a novel pre-existing antibody specific to the extended C-terminus of GSK2862277. Despite the reduced binding of GSK2862277 to pre-existing HAVH autoantibodies, adverse effects associated with the presence of a novel pre-existing antibody response specific to the modified dAb framework were identified and highlight the challenge of developing biological antagonists to this class of receptor.

  6. Nerve growth factor and receptor expression in rheumatoid arthritis and spondyloarthritis

    NARCIS (Netherlands)

    Barthel, C.; Yeremenko, N.; Jacobs, R.; Schmidt, R.E.; Bernateck, M.; Zeidler, H.; Tak, P.P.; Baeten, D.; Rihl, M.

    2009-01-01

    Introduction We previously described the presence of nerve growth factor receptors in the inflamed synovial compartment. Here we investigated the presence of the corresponding nerve growth factors, with special focus on nerve growth factor (NGF). Methods mRNA expression levels of four ligands (NGF,

  7. Association of coatomer proteins with the beta-receptor for platelet-derived growth factor

    DEFF Research Database (Denmark)

    Hansen, Klaus; Rönnstrand, L; Rorsman, C

    1997-01-01

    of intracellular vesicle transport. In order to explore the functional significance of the interaction between alpha- and beta'-COP and the PDGF receptor, a receptor mutant was made in which the conserved histidine residue 928 was mutated to an alanine residue. The mutant receptor, which was unable to bind alpha......The nonreceptor tyrosine kinase Src binds to and is activated by the beta-receptor for platelet-derived growth factor (PDGF). The interaction leads to Src phosphorylation of Tyr934 in the kinase domain of the receptor. In the course of the functional characterization of this phosphorylation, we...... noticed that components of 136 and 97 kDa bound to a peptide from this region of the receptor in a phosphorylation-independent manner. These components have now been purified and identified as alpha- and beta'-coatomer proteins (COPs), respectively. COPs are a family of proteins involved in the regulation...

  8. Extended Synaptotagmin Interaction with the Fibroblast Growth Factor Receptor Depends on Receptor Conformation, Not Catalytic Activity.

    Science.gov (United States)

    Tremblay, Michel G; Herdman, Chelsea; Guillou, François; Mishra, Prakash K; Baril, Joëlle; Bellenfant, Sabrina; Moss, Tom

    2015-06-26

    We previously demonstrated that ESyt2 interacts specifically with the activated FGF receptor and is required for a rapid phase of receptor internalization and for functional signaling via the ERK pathway in early Xenopus embryos. ESyt2 is one of the three-member family of Extended Synaptotagmins that were recently shown to be implicated in the formation of endoplasmic reticulum (ER)-plasma membrane (PM) junctions and in the Ca(2+) dependent regulation of these junctions. Here we show that ESyt2 is directed to the ER by its putative transmembrane domain, that the ESyts hetero- and homodimerize, and that ESyt2 homodimerization in vivo requires a TM adjacent sequence but not the SMP domain. ESyt2 and ESyt3, but not ESyt1, selectively interact in vivo with activated FGFR1. In the case of ESyt2, this interaction requires a short TM adjacent sequence and is independent of receptor autophosphorylation, but dependent on receptor conformation. The data show that ESyt2 recognizes a site in the upper kinase lobe of FGFR1 that is revealed by displacement of the kinase domain activation loop during receptor activation.

  9. Epidermal growth factor receptor (EGFR) and EGFR mutations, function and possible role in clinical trials

    DEFF Research Database (Denmark)

    Voldborg, B R; Damstrup, L; Spang-Thomsen, M;

    1997-01-01

    The epidermal growth factor receptor (EGFR) is a growth factor receptor that induces cell differentiation and proliferation upon activation through the binding of one of its ligands. The receptor is located at the cell surface, where the binding of a ligand activates a tyrosine kinase...... in the intracellular region of the receptor. This tyrosine kinase phosphorylates a number of intracellular substrates that activates pathways leading to cell growth, DNA synthesis and the expression of oncogenes such as fos and jun. EGFR is thought to be involved the development of cancer, as the EGFR gene is often...... amplified, and/or mutated in cancer cells. In this review we will focus on: (I) the structure and function of EGFR, (II) implications of receptor/ligand coexpression and EGFR mutations or overexpression, (III) its effect on cancer cells, (IV) the development of the malignant phenotype and (V) the clinical...

  10. Troglitazone inhibits cell proliferation by attenuation of epidermal growth factor receptor signaling independent of peroxisome proliferator-activated receptor γ

    Institute of Scientific and Technical Information of China (English)

    Xiaoqi Li; Xuanming Yang; Youli Xu; Xuejun Jiang; Xin Li; Fajun Nan; Hong Tang

    2009-01-01

    Peroxisome proliferator-activated receptors (PPAR) belong to the nuclear hormone receptor superfamily of ligand-dependent transcription factors. Recent results have shown that agonists of PPARy, such as troglitazone (TGZ), can inhibit cell proliferation and promote cell differentiation independent of PPARγ. In the present study, we provide evidence that TGZ may bind directly to EGFR and trigger its signaling and internalization independent of PPARγ. Detailed studies revealed that prolonged incubation with TGZ effectively attenuated EGFR signaling by target-ing the receptor to the endo-lysosomal degradation machinery. Although the extracellular signal-regulated kinase-signaling pathway was transiently activated by TGZ in EGFR overexpressing cancer cells, inhibition of EGF-induced Akt phosphorylation most likely accounted for the growth arrest of tumor cells caused by TGZ at pharmacologically achievable concentrations. Therefore, we have provided a new line of evidence indicating that TGZ inhibits cell pro-liferation by promoting EGFR degradation and attenuating Akt phosphorylation.

  11. Transactivation of Epidermal Growth Factor Receptor by G Protein-Coupled Receptors: Recent Progress, Challenges and Future Research

    Directory of Open Access Journals (Sweden)

    Zhixiang Wang

    2016-01-01

    Full Text Available Both G protein-coupled receptors (GPCRs and receptor-tyrosine kinases (RTKs regulate large signaling networks, control multiple cell functions and are implicated in many diseases including various cancers. Both of them are also the top therapeutic targets for disease treatment. The discovery of the cross-talk between GPCRs and RTKs connects these two vast signaling networks and complicates the already complicated signaling networks that regulate cell signaling and function. In this review, we focus on the transactivation of epidermal growth factor receptor (EGFR, a subfamily of RTKs, by GPCRs. Since the first report of EGFR transactivation by GPCR, significant progress has been made including the elucidation of the mechanisms underlying the transactivation. Here, we first provide a basic picture for GPCR, EGFR and EGFR transactivation by GPCR. We then discuss the progress made in the last five years and finally provided our view of the future challenge and future researches needed to overcome these challenges.

  12. Characterization of LPS-induced TNFα factor (LITAF) from orange-spotted grouper, Epinephelus coioides.

    Science.gov (United States)

    Cai, Jia; Huang, Youhua; Wei, Shina; Ouyang, Zhengliang; Huang, Xiaohong; Qin, Qiwei

    2013-12-01

    Lipopolysaccharide-induced TNFα factor (LITAF) is an important transcription factor that mediates cell apoptosis and inflammatory response. In the present study, we cloned and characterized a LITAF gene from orange-spotted grouper (Epinephelus coioides) (Ec-LITAF). Ec-LITAF encoded a predicted 142 amino acid protein which shared 74% identity to sablefish (Anoplopoma fimbria) LITAF homolog. Multiple amino acid alignment showed that Ec-LITAF contained a typical LITAF domain with two CXXC motifs. Phylogenetic analysis indicated that Ec-LITAF was closely related to that of sablefish. Ec-LITAF mRNA was widely expressed in different tissues and its expression level in spleen was up-regulated after Singapore grouper iridovirus (SGIV) infection. Subcellular localization analysis revealed that the distribution of Ec-LITAF showed diffuse and aggregated patterns in cytoplasm. Interestingly, the distribution of Ec-LITAF overlayed with a viral LITAF homolog (vLITAF) encoded by SGIV. Overexpression of Ec-LITAF in vitro up-regulated the expression of tumor necrosis factors (TNF1 and TNF2) and TNF receptors (TNFR1 and TNFR2), and the expression of itself initiated apoptosis in fish cells. In addition, overexpression of Ec-LITAF not only accelerated SGIV infection induced CPE and cell death, but also increased viral gene transcription. Taken together, our data suggested that Ec-LITAF might play crucial roles during SGIV replication.

  13. DETERMINATION OF SERUM SOLUBLE MACROPHAGE COLONY- STIMULATING FACTOR RECEPTOR LEVELS IN PATIENTS with hematological diseases

    Institute of Scientific and Technical Information of China (English)

    RAO; Qing

    2001-01-01

    [1]Heaney MK, Golde DW. Soluble receptors in human disease [J]. J Leukoc Biol 1998; 61:135.[2]Fix P, Praloram V. M-CSF: Haematopoietic growth factor or inflammatory cytokine [J]? Cytokine 1998; 10:32.[3]Sherr C. Colony-stimulating factor ? 1 receptor [J]. Blood 1990; 75:1.[4]Downing JR, Roussel MF, Sherr CJ. Ligand and protein kinase C down modulate the colony-stimulating factor 1 receptor by independent mechanisms [J]. Mol Cell Biol 1989; 9:2890.[5]Baker AH, Cachia PG, Tennant GB, et al. A novel CSF-1 binding factor in a patient in complete remission following cytotoxic therapy for lymphoma [J]. Br J Haematol 1995; 89:219.[6]Wu KF, Zheng GG, Rao Q, et al. Cellular macrophage colony-stimulating factor and its role [J]. Hematologica 1999; 84:951.[7]Rao Q, Han JS, Geng YQ, et al. Antigen association of J6-1 cell membrane associated factor receptor with macrophage colony-stimulating factor receptor [J]. Chin J Cancer Res 1999; 11:235.[8]Rao Q, Han JS, Geng YQ, et al. Quantitation of human soluble macrophage colony stimulating factor receptor in human serum by ELISA assay [J]. Exp Hematol 1999; 27:105.[9]Luo SQ, Zheng DX, Liu YX, et al. Analysis of the ligand-binding domain of macrophage colony- stimulating factor receptor [J]. Chin Sci Bull 2000; 45:1191.[10]Wypych J, Bennett LG, Schwartz MG, et al. Soluble Kit receptor in human serum [J]. Blood 1995; 85:66.[11]Tiesman J, Hart CE. Identification of a soluble receptor for platelet-derived growth factor in cell-conditioned medium and human plasma [J]. J Biol Chem 1993; 269:9621.[12]Zhang Q, Xue YP, Song YH, et al. Expression of cellular M-CSF and M-CSFR in hematopoietic cells [J]. Chin J Hematol 1999; 20:249.[13]Tang SS, Liu HZ, Chen GB, et al. Internalization mediated by membrane-bound macrophage colony- stimulating factor and half-life of cell associated macrophage colony-stimulating factor and its receptor [J]. Chin Sci Bull 2000; 45:627.[14]Zeigler ZR

  14. Asymmetric Receptor Contact is Required for Tyrosine Autophosphorylation of Fibroblast Growth Factor Receptor in Living Cells

    Energy Technology Data Exchange (ETDEWEB)

    Bae, J.; Boggon, T; Tomé, F; Mandiyan, V; Lax, I; Schlessinge, J

    2010-01-01

    Tyrosine autophosphorylation of receptor tyrosine kinases plays a critical role in regulation of kinase activity and in recruitment and activation of intracellular signaling pathways. Autophosphorylation is mediated by a sequential and precisely ordered intermolecular (trans) reaction. In this report we present structural and biochemical experiments demonstrating that formation of an asymmetric dimer between activated FGFR1 kinase domains is required for transphosphorylation of FGFR1 in FGF-stimulated cells. Transphosphorylation is mediated by specific asymmetric contacts between the N-lobe of one kinase molecule, which serves as an active enzyme, and specific docking sites on the C-lobe of a second kinase molecule, which serves a substrate. Pathological loss-of-function mutations or oncogenic activating mutations in this interface may hinder or facilitate asymmetric dimer formation and transphosphorylation, respectively. The experiments presented in this report provide the molecular basis underlying the control of transphosphorylation of FGF receptors and other receptor tyrosine kinases.

  15. The nerve growth factor and its receptors in airway inflammatory diseases.

    Science.gov (United States)

    Freund-Michel, V; Frossard, N

    2008-01-01

    The nerve growth factor (NGF) belongs to the neurotrophin family and induces its effects through activation of 2 distinct receptor types: the tropomyosin-related kinase A (TrkA) receptor, carrying an intrinsic tyrosine kinase activity in its intracellular domain, and the receptor p75 for neurotrophins (p75NTR), belonging to the death receptor family. Through activation of its TrkA receptor, NGF activates signalling pathways, including phospholipase Cgamma (PLCgamma), phosphatidyl-inositol 3-kinase (PI3K), the small G protein Ras, and mitogen-activated protein kinases (MAPK). Through its p75NTR receptor, NGF activates proapoptotic signalling pathways including the MAPK c-Jun N-terminal kinase (JNK), ceramides, and the small G protein Rac, but also activates pathways promoting cell survival through the transcription factor nuclear factor-kappaB (NF-kappaB). NGF was first described by Rita Levi-Montalcini and collaborators as an important factor involved in nerve differentiation and survival. Another role for NGF has since been established in inflammation, in particular of the airways, with increased NGF levels in chronic inflammatory diseases. In this review, we will first describe NGF structure and synthesis and NGF receptors and their signalling pathways. We will then provide information about NGF in the airways, describing its expression and regulation, as well as pointing out its potential role in inflammation, hyperresponsiveness, and remodelling process observed in airway inflammatory diseases, in particular in asthma.

  16. Expression of tumor necrosis factor related apoptosis inducing ligand receptor in glioblastoma

    Institute of Scientific and Technical Information of China (English)

    Dongling Gao; Zhongwei Zhao; Hongxin Zhang; Lan Zhang; Kuisheng Chen; Yunhan Zhang

    2008-01-01

    BACKGROUND: Receptors for tumor necrosis factor related apoptosis inducing ligand (TRAIL) include death receptor 4, death receptor 5, decoy receptor 1, and decoy receptor 2. Activation of death receptor 4 and 5 selectively kills tumor cells.OBJECTIVE: To detect TRAIL receptor expression in glioblastoma by immunohistochemistry and RT-PCR and to compare this expression to that in normal brain tissue.DESIGN: Observational analysis.SETTING: Department of Pathology, the First Affiliated Hospital of Zhengzhou University; Henan Tumor Pathology Key Laboratory.PARTICIPANTS: Twenty-five patients (17 males and 8 females) who received glioblastoma resection were selected from the Fifth Affiliated Hospital of Zhengzhou University, between September 2003 to June 2004. All glioblastoma samples were diagnosed pathologically. Twenty patients (12 males and 8 females) with craniocerebral injury who received normal brain tissue resection were selected in the same time period. There were no significant differences in sex and age between glioblastoma patients or between craniocerebral injury patients (P>0.05). All patients and appropriate relatives provided informed consent, and this study was approved by the local research ethics committee.METHODS: Polyclonal antibody against TRAIL receptors and an immunohistochemical kit (batch number: 200502) were purchased from Boster Company, Wuhan. Immunohistochemistry: Expression of death receptor 4, death receptor 5, decoy receptor 1, and decoy receptor 2 were observed in both glioblastoma and normal brain tissue. The experiment was performed according to the kit instructions, and positive staining was brown-yellow. Assessment: There were no positive signals (-); weakly positive signals, positive cells75% (++++). Evaluation: Expression levels of TRAIL receptors were estimated in both normal brain tissue and glioblastoma. Expression of decoy receptor 1 and decoy receptor 2 mRNA in glioblastoma were detected by reverse transcription polymerase

  17. Epidermal growth factor receptor mutation enhances expression of vascular endothelial growth factor in lung cancer.

    Science.gov (United States)

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

    2016-12-01

    Epidermal growth factor receptor (EGFR) activation has been demonstrated to have a critical role in tumor angiogenesis. In the present study, the correlation between EGFR mutations and vascular endothelial growth factor (VEGF) was investigated in lung cancer cell lines and non-small-cell lung cancer (NSCLC) tumor tissues. VEGF levels were significantly increased in culture medium of lung cancer cells and NSCLC tissues with EGFR mutations (H1650 vs. A549, P=0.0399; H1975 vs. A549, Plung cancer cell lines expressing mutant (exon 19 deletion, E746-A750; exon 21 missense mutation, L858R) and wild-type EGFR genes were established. Significantly increased expression of VEGF and stronger inhibitory effects of gefitinib to VEGF expression were observed in exon 19 deletion stable lung cancer cells (exon 19 deletion vs. wild-type EGFR, P=0.0005). The results of the present study may provide an insight into the association of mutant EGFR and VEGF expression in lung cancer, and may assist with further development of targeted therapy for NSCLC in the future.

  18. Increase of tumor necrosis factor receptor 1 expression in women with unexplained early spontaneous abortion

    Institute of Scientific and Technical Information of China (English)

    YAN Chun-fang; YU Xue-wen; JIN Hui; LI Xu

    2004-01-01

    To investigate membrane tumor necrosis factor receptor 1 protein expression level in decidua andconcentration of soluble tumor necrosis factor receptor 1 in serum in women with unexplained early spontaneous abortion,threatened abortion, and compare the levels with healthy pregnant women. Methods: Thirty-seven women with unexplainedearly spontaneous abortion, 27 women with threatened abortion, and 34 healthy pregnant women undergoing artificial abortionof pregnancy at 6 - 10 weeks of gestation were selected. Decidual samples were collected when women were undergoing arti-ficial abortion, and blood samples were collected at the same time. The level of membrane tumor necrosis factor receptor 1 indecidua was detected by flow cytometer, and the concentration of soluble tumor necrosis factor receptor 1 in sera was mea-sured with an enzyme-linked immunosorbent assay. Results: The ercentages of membrane tumor necrosis factor receptor 1positive decidual cells were 16.42 ± 7.10 Mean ± SD for women with unexplained early spontaneous abortion and 13.14 ±6.30 for healthy pregnant women ( P < 0.05). Serum oncentration of soluble tumor necrosis factor receptor 1 was signifi-cantly higher in women with unexplained early spontaneous abortion than in healthy pregnant women and in women withthreatened abortion, and no difference was found between healthy pregnant women and women with threatened abortion.Conclusion: Women with unexplained early spontaneous abortion present significantly higher expression of tumor necrosisfactor receptor 1 than healthy pregnant women, suggesting that over-expression of tumor necrosis factor receptor 1 may cont-ribute to the development of early spontaneous abortion.

  19. The oncogenic epidermal growth factor receptor variant Xiphophorus melanoma receptor kinase induces motility in melanocytes by modulation of focal adhesions.

    Science.gov (United States)

    Meierjohann, Svenja; Wende, Elisabeth; Kraiss, Anita; Wellbrock, Claudia; Schartl, Manfred

    2006-03-15

    One of the most prominent features of malignant melanoma is the fast generation of metastasizing cells, resulting in the poor prognosis of patients with this tumor type. For this process, cells must gain the ability to migrate. The oncogenic receptor Xmrk (Xiphophorus melanoma receptor kinase) from the Xiphophorus melanoma system is a mutationally activated version of the epidermal growth factor receptor that induces the malignant transformation of pigment cells. Here, we show that the activation of Xmrk leads to a clear increase of pigment cell motility in a fyn-dependent manner. Stimulation of Xmrk induces its interaction with the focal adhesion kinase (FAK) and the interaction of active, receptor-bound fyn with FAK. This results in changes in FAK activity and induces the modulation of stress fibers and focal adhesions. Overexpression of dominant-negative FAK shows that the activity of innate FAK and a receptor-induced focal adhesion turnover are a prerequisite for pigment cell migration. Our findings show that in our system, Xmrk is sufficient for the induction of pigment cell motility and underlines a role of the src family protein tyrosine kinase fyn in melanoma development and progression.

  20. [Dependence of EGF receptor and STAT factor activation on redox of A431 cells].

    Science.gov (United States)

    Gonchar, I V; Burova, E B; Dorosh, V N; Gamaleĭ, I A; Nikol'skiĭ, N N

    2003-01-01

    Reactive oxygen species (ROS) were established to play an important role in cellular signaling as second messengers by integrating different pathways. Recently, we showed that EGF initiated a rapid tyrosine phosphorylation of both EGF-receptor and STAT factors with simultaneous increase in the intracellular ROS level. Now, we have investigated the effect of intracellular red-ox state on EGF- and H2O2-induced activation of EGF receptor, STAT1 and STAT3. We demonstrated that the pretreatment of A431 cells with antioxidant N-acetyl-L-cysteine (NAC) partly reduced the level of EGF-induced phosphorylation of proteins under investigation. Besides, H2O2-induced activation of EGF receptor, and STAT factors was fully prevented by NAC pretreatment. The inhibition of ROS generation by DPI declined EGF-dependent activation of EGF receptor and STAT factors to basal level. Our results demonstrate the essential role of cellular red-ox status in the modulation of EGF-mediated activation of receptor and STAT factors. We have postulated that EGF-induced ROS generation is a very important initial event promoting physiological activation of EGF receptor and subsequent STAT factor activation.

  1. Blocking transforming growth factor- receptor signaling down-regulates transforming growth factor-β1 autoproduction in keloid fibroblasts

    Institute of Scientific and Technical Information of China (English)

    刘伟; 蔡泽浩; 王丹茹; 武小莉; 崔磊; 商庆新; 钱云良; 曹谊林

    2002-01-01

    Objective: To study transforming growth factor-β1(TGF-β1) autoproduction in keloid fibroblasts and theregulation effect of blocking TGF-β intracellular signalingon rhTGF-β1 autoproduction.Methods: Keloid fibroblasts cultured in vitro weretreated with either rhTGF-β1 (5 ng/ml ) or recombinantadenovirus containing a truncated type II TGF-β receptorgene (50 pfu/cell ). Their effects of regulating geneexpression of TGF-β1 and its receptor I and II wereobserved with Northern blot.Results: rhTGF-β1 up-regulated the gene expressionof TGF-β1 and receptor I, but not receptor II. Over-expression of the truncated receptor II down-regulated thegene expression of TGF-β1 and its receptor I, but notreceptor II.Conclusions: TGF-β1 autoproduction was observed inkeloid fibroblasts. Over-expression of the truncated TGF-βreceptor H decreased TGF-β1 autoproduction via blockingTGF-β receptor signaling.

  2. Internalization mechanisms of the epidermal growth factor receptor after activation with different ligands.

    Directory of Open Access Journals (Sweden)

    Lasse Henriksen

    Full Text Available The epidermal growth factor receptor (EGFR regulates normal growth and differentiation, but dysregulation of the receptor or one of the EGFR ligands is involved in the pathogenesis of many cancers. There are eight ligands for EGFR, however most of the research into trafficking of the receptor after ligand activation focuses on the effect of epidermal growth factor (EGF and transforming growth factor-α (TGF-α. For a long time it was believed that clathrin-mediated endocytosis was the major pathway for internalization of the receptor, but recent work suggests that different pathways exist. Here we show that clathrin ablation completely inhibits internalization of EGF- and TGF-α-stimulated receptor, however the inhibition of receptor internalization in cells treated with heparin-binding EGF-like growth factor (HB-EGF or betacellulin (BTC was only partial. In contrast, clathrin knockdown fully inhibits EGFR degradation after all ligands tested. Furthermore, inhibition of dynamin function blocked EGFR internalization after stimulation with all ligands. Knocking out a number of clathrin-independent dynamin-dependent pathways of internalization had no effect on the ligand-induced endocytosis of the EGFR. We suggest that EGF and TGF-α lead to EGFR endocytosis mainly via the clathrin-mediated pathway. Furthermore, we suggest that HB-EGF and BTC also lead to EGFR endocytosis via a clathrin-mediated pathway, but can additionally use an unidentified internalization pathway or better recruit the small amount of clathrin remaining after clathrin knockdown.

  3. Combined adenovirus-mediated artificial microRNAs targeting mfgl2, mFas, and mTNFR1 protect against fulminant hepatic failure in mice.

    Directory of Open Access Journals (Sweden)

    Dong Xi

    Full Text Available Hepatitis B virus (HBV-related acute-on-chronic liver failure (ACLF has a poor prognosis with high in-hospital mortality. Hepatic and circulating inflammatory cytokines, such as fibrinogen like protein 2 (fgl2, FasL/Fas, and TNFα/TNFR1, play a significant role in the pathophysiology of ACLF. This study aimed to investigate the therapeutic effect of recombinant adenoviral vectors carrying constructed DNA code for non-native microRNA (miRNA targeting mouse fgl2 (mfgl2 or both mFas and mTNFR1 on murine hepatitis virus (MHV-3-induced fulminant hepatitis in BALB/cJ mice. Artificial miRNA eukaryotic expression plasmids against mfgl2, mFas, and mTNFR1 were constructed, and their inhibitory effects on the target genes were confirmed in vitro. pcDNA6.2-mFas-mTNFR1- miRNA,which expresses miRNA against both mFas and mTNFR1 simultaneously,was constructed. To construct a miRNA adenovirus expression vector against mfgl2, pcDNA6.2-mfgl2-miRNA was cloned using Gateway technology. Ad-mFas-mTNFR1- miRNA was also constructed by the same procedure. Adenovirus vectors were delivered by tail-vein injection into MHV-3-infected BALB/cJ mice to evaluate the therapeutic effect. 8 of 18 (44.4% mice recovered from fulminant viral hepatitis in the combined interference group treated with Ad-mfgl2-miRNA and Ad-mFas-mTNFR1-miRNA. But only 4 of 18 (22.2% mice receiving Ad-mfgl2-miRNA and 3 of 18 (16.7% mice receiving Ad-mFas-mTNFR1- miRNA survived. These adenovirus vectors significantly ameliorated inflammatory infiltration, fibrin deposition, hepatocyte necrosis and apoptosis, and prolonged survival time. Our data illustrated that combined interference using adenovirus-mediated artificial miRNAs targeting mfgl2, mFas, and mTNFR1 might have significant therapeutic potential for the treatment of fulminant hepatitis.

  4. Insulin-like growth factor II: complexity of biosynthesis and receptor binding

    DEFF Research Database (Denmark)

    Gammeltoft, S; Christiansen, Jan; Nielsen, F C

    1991-01-01

    , Man-6-P induces cellular responses. We have studied rat brain neuronal precursor cells where Man-6-P acted as a mitogen suggesting that phosphomannosylated proteins may act as growth factors via the Man-6-P/IGF-II receptor. In conclusion, the gene expression and mechanism of action of IGF-II is very...... and the mannose-6-phosphate (Man-6-P)/IGF-II receptor. There is consensus that the cellular effects of IGF-II are mediated by the IGF-I receptor via activation of its intrinsic tyrosine kinase. The Man-6-P/IGF-II receptor is involved in endocytosis of lysosomal enzymes and IGF-II. In selected cell types, however...... complex suggesting that its biological actions can be regulated at different levels including the transcription, translation, posttranslational processing, receptor binding and intracellular signalling....

  5. Receptor-mediated choreography of life and death.

    Science.gov (United States)

    Bhardwaj, Anjana; Aggarwal, Bharat B

    2003-09-01

    The cytokine tumor necrosis factor was originally identified as a protein that kills tumor cells. So far, 18 distinct members of this family have been identified. All of them regulate cell survival, proliferation, differentiation, and cell death, also called apoptosis. The apoptosis induced by TNF, and other members of the family, for example, FasL, VEGI, and TRAIL is mediated through death receptors. The apoptotic signals by these cytokines are transduced by eight different death domain- (DD) containing receptors (TNFR1, also called DR1; Fas, also called DR2; DR3, DR4, DR5, DR6, NGFR, and EDAR). The intracellular portion of all these receptors contains a region approximately 80 amino acids long referred to as the "death domain." Upon activation by its ligand, the DD recruits various proteins that mediate both death and proliferation of the cells. These proteins in turn recruit other proteins via their DDs or death effector domains. The actual destruction of the cell, however, is accomplished by serial activation of a family of proteases referred to as caspases. Cell death is negatively regulated by a family of proteins that includes decoy receptors, silencer of DD, sentrin, cellular FLICE inhibitory protein, cellular inhibitors of apoptosis, and survivin. This review is an attempt to describe how these negative and positive players of cell death perform a harmonious dance with each other.

  6. Glucocorticoid receptor and nuclear factor kappa-b affect three-dimensional chromatin organization

    NARCIS (Netherlands)

    Kuznetsova, T.; Wang, S.Y.; Rao, N.A.; Mandoli, A.; Martens, J.H.; Rother, N; Aartse, A.; Groh, L.; Janssen-Megens, E.M.; Li, G.; Ruan, Y.; Logie, C.; Stunnenberg, H.G.

    2015-01-01

    BACKGROUND: The impact of signal-dependent transcription factors, such as glucocorticoid receptor and nuclear factor kappa-b, on the three-dimensional organization of chromatin remains a topic of discussion. The possible scenarios range from remodeling of higher order chromatin architecture by activ

  7. The transforming growth factor-beta receptor genes and the risk of intracranial aneurysms

    NARCIS (Netherlands)

    Ruigrok, Ynte M.; Baas, Annette F.; Medic, Jelena; Wijmenga, Cisca; Rinkel, Gabriel J. E.

    2012-01-01

    Background Mutations in the receptor genes of the transforming growth factor beta pathway, TGFBR1 and TGFBR2, cause syndromes with thoracic aortic aneurysms, while genetic variants in TGFBR1 and TGFBR2 are associated with abdominal aortic aneurysms. The transforming growth factor-beta pathway may be

  8. Glucocorticoid receptor and nuclear factor kappa-b affect three-dimensional chromatin organization

    NARCIS (Netherlands)

    Kuznetsova, T.; Wang, S.Y.; Rao, N.A.; Mandoli, A.; Martens, J.H.; Rother, N; Aartse, A.; Groh, L.; Janssen-Megens, E.M.; Li, G.; Ruan, Y.; Logie, C.; Stunnenberg, H.G.

    2015-01-01

    BACKGROUND: The impact of signal-dependent transcription factors, such as glucocorticoid receptor and nuclear factor kappa-b, on the three-dimensional organization of chromatin remains a topic of discussion. The possible scenarios range from remodeling of higher order chromatin architecture by

  9. Epidermal growth factor receptor signalling contributes to house dust mite-induced epithelial barrier dysfunction

    NARCIS (Netherlands)

    Heijink, I H; van Oosterhout, A; Kapus, A

    2010-01-01

    Impaired airway epithelial barrier function has emerged as a key factor in the pathogenesis of allergic asthma. We aimed to discern the involvement of the epidermal growth factor receptor (EGFR) in allergen-induced epithelial barrier impairment, as we previously observed that house dust mite (HDM) s

  10. Pharmacological targeting of the KIT growth factor receptor: a therapeutic consideration for mast cell disorders

    DEFF Research Database (Denmark)

    Jensen, Bettina Margrethe; Akin, C; Gilfillan, A M

    2008-01-01

    KIT is a member of the tyrosine kinase family of growth factor receptors which is expressed on a variety of haematopoietic cells including mast cells. Stem cell factor (SCF)-dependent activation of KIT is critical for mast cell homeostasis and function. However, when KIT is inappropriately activa...

  11. Modulator effects of interleukin-1beta and tumor necrosis factor-alpha on AMPA-induced excitotoxicity in mouse organotypic hippocampal slice cultures

    DEFF Research Database (Denmark)

    Bernardino, Liliana; Xapelli, Sara; Silva, Ana P

    2005-01-01

    The inflammatory cytokines interleukin-1beta and tumor necrosis factor-alpha (TNF-alpha) have been identified as mediators of several forms of neurodegeneration in the brain. However, they can produce either deleterious or beneficial effects on neuronal function. We investigated the effects...... of mouse recombinant TNF-alpha (10 ng/ml) enhanced excitotoxicity when the cultures were simultaneously exposed to AMPA and to this cytokine. Decreasing the concentration of TNF-alpha to 1 ng/ml resulted in neuroprotection against AMPA-induced neuronal death independently on the application protocol....... By using TNF-alpha receptor (TNFR) knock-out mice, we demonstrated that the potentiation of AMPA-induced toxicity by TNF-alpha involves TNF receptor-1, whereas the neuroprotective effect is mediated by TNF receptor-2. AMPA exposure was associated with activation and proliferation of microglia as assessed...

  12. Neurosteroid dehydroepiandrosterone interacts with nerve growth factor (NGF receptors, preventing neuronal apoptosis.

    Directory of Open Access Journals (Sweden)

    Iakovos Lazaridis

    2011-04-01

    Full Text Available The neurosteroid dehydroepiandrosterone (DHEA, produced by neurons and glia, affects multiple processes in the brain, including neuronal survival and neurogenesis during development and in aging. We provide evidence that DHEA interacts with pro-survival TrkA and pro-death p75(NTR membrane receptors of neurotrophin nerve growth factor (NGF, acting as a neurotrophic factor: (1 the anti-apoptotic effects of DHEA were reversed by siRNA against TrkA or by a specific TrkA inhibitor; (2 [(3H]-DHEA binding assays showed that it bound to membranes isolated from HEK293 cells transfected with the cDNAs of TrkA and p75(NTR receptors (K(D: 7.4 ± 1.75 nM and 5.6 ± 0.55 nM, respectively; (3 immobilized DHEA pulled down recombinant and naturally expressed TrkA and p75(NTR receptors; (4 DHEA induced TrkA phosphorylation and NGF receptor-mediated signaling; Shc, Akt, and ERK1/2 kinases down-stream to TrkA receptors and TRAF6, RIP2, and RhoGDI interactors of p75(NTR receptors; and (5 DHEA rescued from apoptosis TrkA receptor positive sensory neurons of dorsal root ganglia in NGF null embryos and compensated NGF in rescuing from apoptosis NGF receptor positive sympathetic neurons of embryonic superior cervical ganglia. Phylogenetic findings on the evolution of neurotrophins, their receptors, and CYP17, the enzyme responsible for DHEA biosynthesis, combined with our data support the hypothesis that DHEA served as a phylogenetically ancient neurotrophic factor.

  13. Changes of expression of estrogen and progestrone receptors, human epithelial growth factor receptor 2 and Ki-67 after neoadjuvant chemotherapy in the treatment of breast cancer.

    Science.gov (United States)

    Li, M L; Dong, Y; Luan, S L; Zhao, Z H; Ning, F L

    2016-01-01

    Recent studies suggest that the development and prognosis of breast cancer is in close correlation to molecular subtype of breast cancer. Neoadjuvant chemotherapy has been extensively applied in the treatment of local breast cancer in advanced stage. In order to verify the correlation between expression changes of estrogen receptor, progestrone receptor, human epithelial growth factor receptor 2 and Ki-67 after neoadjuvant chemotherapy and neoadjuvant chemotherapy, we studied 120 patients with stage IIAIIIC breast cancer who underwent neoadjuvant chemotherapy in Binzhou Medical University Hospital, Shandong, China from February 2011 to February 2015. Clinical characteristics were retrospectively analyzed. The expression of estrogen receptor, progesterone receptor, human epithelial growth factor receptor 2 and Ki-67 of patients were detected using the immunohistochemical method before and after neoadjuvant chemotherapy. The results suggest that the overall remission rate of neoadjuvant chemotherapy was 76.7% (92/120) of which 16.7% (20/120) of cases had complete remission, 60% (72/120) had partial remission and 23.3% (28/120) were stable. There were no cases of progressive disease. The property of estrogen receptor and the expression of Ki-67 of primary tumor were correlated to the remission rate of neoadjuvant chemotherapy (P less than 0.05). The expression of Ki-67 had a significant decline after neoadjuvant chemotherapy, and the difference had statistical significance (P less than 0.05). The difference in expression of estrogen receptor, progesterone receptor and human epithelial growth factor receptor 2 before and after neoadjuvant chemotherapy had statistical significance (P > 0.05). Hence, it can be concluded that breast cancer patients with negative estrogen receptor expression and high Ki-67 expression before neoadjuvant chemotherapy can achieve better curative effects. Neoadjuvant chemotherapy cannot change the expression states of estrogen receptor

  14. Stabilization of the bioactivity of tumor necrosis factor by its soluble receptors

    OpenAIRE

    1992-01-01

    The receptors for tumor necrosis factor (TNF) exist in cell-associated as well as soluble forms, both binding specifically to TNF. Since the soluble forms of TNF receptors (sTNF-Rs) can compete with the cell- associated TNF receptors for TNF, it was suggested that they function as inhibitors of TNF activity; at high concentrations, the sTNF-Rs indeed inhibit TNF effects. However, we report here that in the presence of low concentrations of the sTNF-Rs, effects of TNF whose induction depend on...

  15. Fibroblast growth factor receptor signaling is essential for lens fiber cell differentiation

    OpenAIRE

    Zhao, Haotian; Yang, Tianyu; Madakashira, Bhavani P.; Thiels, Cornelius A.; Bechtle, Chad A.; Garcia, Claudia M.; Zhang, Huiming; Yu, Kai; Ornitz, David M.; Beebe, David C.; Robinson, Michael L.

    2008-01-01

    The vertebrate lens provides an excellent model to study the mechanisms that regulate terminal differentiation. Although fibroblast growth factors (FGFs) are thought to be important for lens cell differentiation, it is unclear which FGF receptors mediate these processes during different stages of lens development. Deletion of three FGF receptors (Fgfr1-3) early in lens development demonstrated that expression of only a single allele of Fgfr2 or Fgfr3 was sufficient for grossly normal lens dev...

  16. Corticotropin-releasing factor receptors and stress-related alterations of gut motor function.

    OpenAIRE

    2007-01-01

    International audience; Over the past few decades, corticotropin-releasing factor (CRF) signaling pathways have been shown to be the main coordinators of the endocrine, behavioral, and immune responses to stress. Emerging evidence also links the activation of CRF receptors type 1 and type 2 with stress-related alterations of gut motor function. Here, we review the role of CRF receptors in both the brain and the gut as part of key mechanisms through which various stressors impact propulsive ac...

  17. A receptor model for urban aerosols based on oblique factor analysis

    DEFF Research Database (Denmark)

    Keiding, Kristian; Sørensen, Morten S.; Pind, Niels

    1987-01-01

    A procedure is outlined for the construction of receptor models of urban aerosols, based on factor analysis. The advantage of the procedure is that the covariation of source impacts is included in the construction of the models. The results are compared with results obtained by other receptor-modelling...... procedures. It was found that procedures based on correlating sources were physically sound as well as in mutual agreement. Procedures based on non-correlating sources were found to generate physically obscure models....

  18. Colony stimulating factor 1 receptor inhibition eliminates microglia and attenuates brain injury after intracerebral hemorrhage.

    Science.gov (United States)

    Li, Minshu; Li, Zhiguo; Ren, Honglei; Jin, Wei-Na; Wood, Kristofer; Liu, Qiang; Sheth, Kevin N; Shi, Fu-Dong

    2017-07-01

    Microglia are the first responders to intracerebral hemorrhage, but their precise role in intracerebral hemorrhage remains to be defined. Microglia are the only type of brain cells expressing the colony-stimulating factor 1 receptor, a key regulator for myeloid lineage cells. Here, we determined the effects of a colony-stimulating factor 1 receptor inhibitor (PLX3397) on microglia and the outcome in the context of experimental mouse intracerebral hemorrhage. We show that PLX3397 effectively depleted microglia, and the depletion of microglia was sustained after intracerebral hemorrhage. Importantly, colony-stimulating factor 1 receptor inhibition attenuated neurodeficits and brain edema in two experimental models of intracerebral hemorrhage induced by injection of collagenase or autologous blood. The benefit of colony-stimulating factor 1 receptor inhibition was associated with reduced leukocyte infiltration in the brain and improved blood-brain barrier integrity after intracerebral hemorrhage, and each observation was independent of lesion size or hematoma volume. These results demonstrate that suppression of colony-stimulating factor 1 receptor signaling ablates microglia and confers protection after intracerebral hemorrhage.

  19. The TNF receptor and Ig superfamily members form an integrated signaling circuit controlling dendritic cell homeostasis

    Science.gov (United States)

    De Trez, Carl; Ware, Carl F.

    2008-01-01

    Dendritic cells (DC) constitute the most potent antigen presenting cells of the immune system, playing a key role bridging innate and adaptive immune responses. Specialized DC subsets differ depending on their origin, tissue location and the influence of trophic factors, the latter remain to be fully understood. Stromal cell and myeloid-associated Lymphotoxin-β receptor (LTβR) signaling is required for the local proliferation of lymphoid tissue DC. This review focuses the LTβR signaling cascade as a crucial positive trophic signal in the homeostasis of DC subsets. The noncanonical coreceptor pathway comprised of the Immunoglobulin (Ig) superfamily member, B and T lymphocyte attenuator (BTLA) and TNFR superfamily member, Herpesvirus entry mediator (HVEM) counter regulates the trophic signaling by LTβR. Together both pathways form an integrated signaling circuit achieving homeostasis of DC subsets. PMID:18511331

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

    Institute of Scientific and Technical Information of China (English)

    Wei Song; Haixing Xuan; Qishui Lin

    2008-01-01

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

  1. Aberrant expression of leukemia inhibitory factor receptor (LIFR) and leukemia inhibitory factor (LIF) is associated with tubal pregnancy occurrence

    OpenAIRE

    Li, Yong; Sun, Lizhou; ZHAO, Denmei; Ouyang, Jun; Xiang, Mei

    2015-01-01

    Tubal pregnancy is a major cause of maternal death in the first trimester and exploration of its underlying molecular mechanism is of great importance. This study aimed to explore the association of tubal pregnancy with leukemia inhibitory factor (LIF) and leukemia inhibitory factor receptor (LIFR) expression in oviduct tissues. Materials and methods: Immunohistochemistry was performed to probe the differential expression of LIF and LIFR in oviduct tissues among a control group (including NP...

  2. The diminished expression of proangiogenic growth factors and their receptors in gastric ulcers of cirrhotic patients.

    Directory of Open Access Journals (Sweden)

    Jiing-Chyuan Luo

    Full Text Available OBJECTIVES: The pathogenesis of the higher occurrence of peptic ulcer disease in cirrhotic patients is complex. Platelets can stimulate angiogenesis and promote gastric ulcer healing. We compared the expressions of proangiogenic growth factors and their receptors in the gastric ulcer margin between cirrhotic patients with thrombocytopenia and those of non-cirrhotic patients to elucidate possible mechanisms. METHODS: Eligible cirrhotic patients (n = 55 and non-cirrhotic patients (n = 55 who had gastric ulcers were enrolled. Mucosa from the gastric ulcer margin and non-ulcer areas were sampled and the mRNA expressions of the proangiogenic growth factors (vascular endothelial growth factor [VEGF], platelet derived growth factor [PDGF], basic fibroblast growth factor [bFGF] and their receptors (VEGFR1, VEGFR2, PDGFRA, PDGFRB, FGFR1, FGFR2 were measured and compared. Platelet count and the expressions of these growth factors and their receptors were correlated with each other. RESULTS: The two groups were comparable in terms of gender, ulcer size and infection rate of Helicobacter pylori. However, the cirrhotic group were younger in age, had a lower platelet count than those in the non-cirrhotic group (p0.5, p<0.001. CONCLUSIONS: Our findings implied that diminished activity of proangiogenic factors and their receptors may contribute to the pathogenesis of gastric ulcers in cirrhotic patients.

  3. Reducing TNF receptor 2+ regulatory T cells via the combined action of azacitidine and the HDAC inhibitor, panobinostat for clinical benefit in acute myeloid leukemia patients.

    Science.gov (United States)

    Govindaraj, Chindu; Tan, Peter; Walker, Patricia; Wei, Andrew; Spencer, Andrew; Plebanski, Magdalena

    2014-02-01

    Acute myeloid leukemia (AML) provides an environment that enables immune suppression, resulting in functionally defective effector T cells; regulatory T cells (Treg) are significant contributors to the impaired antitumor immune response. As TNF is present at high levels in AML and TNF receptor-2 (TNFR2)-expressing Tregs identify highly functional Tregs, we examine the hypothesis that TNFR2(+) Tregs are a relevant Treg subset in this cancer. We also determine the effect of the novel combinatorial therapy of the demethylating agent, azacitidine with the histone deacetylase inhibitor, panobinostat on Tregs, particularly TNFR2(+) Tregs. Thirty healthy donors and 14 patients with AML were enrolled in this study. Patients were treated with azacitidine and panobinostat for 28-day cycles. The frequency and functional relevance of TNFR2(+) Tregs were analyzed subsequently. We report that TNFR2(+) Tregs are increased in AML and have a high migration potential toward the bone marrow. Furthermore, we demonstrate that the level of TNFR2(+) Tregs in the peripheral blood and the bone marrow of patients are decreased in vivo after exposure to panobinostat and azacitidine. Reductions in TNFR2(+) Tregs were associated with increases in Interferon (IFN)-γ and interleukin (IL)-2 production by effector T cells within the bone marrow and beneficial clinical responses. In vitro mechanistic studies indicated panobinostat as the primary driver for the reduction of Tregs. Our study provides for the first time, in vivo validation of the ability of panobinostat in combination with azacitidine to suppress prevalent TNFR2(+) Tregs, resulting in clinical benefits within patients with AML. ©2013 AACR.

  4. Critical role of the death receptor pathway in the antitumoral effects induced by hispanolone derivatives.

    Science.gov (United States)

    Través, P G; López-Fontal, R; Cuadrado, I; Luque, A; Boscá, L; de las Heras, B; Hortelano, S

    2013-01-10

    Labdane diterpenoids have a broad spectrum of biological activities including antibacterial, antiviral and anti-inflammatory properties. However, little is known about their possible role in the apoptotic cell death machinery. Here, we report that hispanolone derivatives, a group of labdane diterpenoids, induce apoptosis in different tumor cell lines by activating caspase-8 with subsequent participation of mitochondrial signaling. Activation of caspase-8 by hispanolone derivatives was followed by a decrease in mitochondrial membrane potential, the release of apoptotic factors from mitochondria to the cytosol, and activation of caspases-9 and 3. Hispanolone derivatives also led to a time-dependent cleavage of Bid. Inhibition of caspase-8 abrogated these processes, suggesting that the death receptor pathway has a critical role in the apoptotic events induced by hispanolone derivatives. In addition, silencing death receptors with small interfering RNA s or pretreating cells with neutralizing antibodies to Fas ligand, tumor necrosis factor receptor 1 (TNF-R1), and TNF-α receptor 2 (TRAIL) inhibited diterpenoid-induced apoptosis, revealing it to be dependent on these death receptors. Interestingly, hispanolone derivatives had no effect on non-tumor cells. Consistently, in vivo bioluminescence imaging corroborates this antineoplasic effect, as hispanolone derivatives significantly decrease cancer growth in tumor xenograft assays. These data demostrate the antitumoral effects of hispanolone derivatives and provide relevant preclinical validation for the use of these compounds as potent therapeutic agents in cancer treatment.

  5. Vascular endothelial growth factor A and vascular endothelial growth factor receptor 2 expression in non-small cell lung cancer patients: relation to prognosis

    DEFF Research Database (Denmark)

    Bonnesen, Barbara; Pappot, Helle; Holmstav, Julie;

    2009-01-01

    elements in neoplastic cells and their microenvironment have recently been and are continuously developed including drugs inhibiting the angiogenic system. Angiogenic factor vascular endothelial growth factor (VEGF) and its receptor vascular endothelial growth factor receptor 2 (VEGFR2) seem to play key...

  6. Deregulation of Flk-1/vascular endothelial growth factor receptor-2 in fibroblast growth factor receptor-1-deficient vascular stem cell development.

    Science.gov (United States)

    Magnusson, Peetra; Rolny, Charlotte; Jakobsson, Lars; Wikner, Charlotte; Wu, Yan; Hicklin, Daniel J; Claesson-Welsh, Lena

    2004-03-15

    We have employed embryoid bodies derived from murine embryonal stem cells to study effects on vascular development induced by fibroblast growth factor (FGF)-2 and FGF receptor-1, in comparison to the established angiogenic factor vascular endothelial growth factor (VEGF)-A and its receptor VEGF receptor-2. Exogenous FGF-2 promoted formation of morphologically distinct, long slender vessels in the embryoid bodies, whereas VEGF-A-treated bodies displayed a compact plexus of capillaries. FGF-2 stimulation of embryonal stem cells under conditions where VEGF-A/VEGFR-2 function was blocked, led to formation of endothelial cell clusters, which failed to develop into vessels. FGFR-1(-/-) embryoid bodies responded to VEGF-A by establishment of the characteristic vascular plexus, but FGF-2 had no effect on vascular development in the absence of FGFR-1. The FGFR-1(-/-) embryoid bodies displayed considerably increased basal level of vessel formation, detected by immunohistochemical staining for platelet-endothelial cell adhesion molecule (PECAM)/CD31. This basal vascularization was blocked by neutralizing antibodies against VEGFR-2 or VEGF-A and biochemical analyses indicated changes in regulation of VEGFR-2 in the absence of FGFR-1 expression. We conclude that VEGF-A/VEGFR-2-dependent vessel formation occurs in the absence of FGF-2/FGFR-1, which, however, serve to modulate vascular development.

  7. Interactions between Type III receptor tyrosine phosphatases and growth factor receptor tyrosine kinases regulate tracheal tube formation in Drosophila

    Directory of Open Access Journals (Sweden)

    Mili Jeon

    2012-04-01

    The respiratory (tracheal system of the Drosophila melanogaster larva is an intricate branched network of air-filled tubes. Its developmental logic is similar in some ways to that of the vertebrate vascular system. We previously described a unique embryonic tracheal tubulogenesis phenotype caused by loss of both of the Type III receptor tyrosine phosphatases (RPTPs, Ptp4E and Ptp10D. In Ptp4E Ptp10D double mutants, the linear tubes in unicellular and terminal tracheal branches are converted into bubble-like cysts that incorporate apical cell surface markers. This tube geometry phenotype is modulated by changes in the activity or expression of the epidermal growth factor receptor (Egfr tyrosine kinase (TK. Ptp10D physically interacts with Egfr. Here we demonstrate that the Ptp4E Ptp10D phenotype is the consequence of the loss of negative regulation by the RPTPs of three growth factor receptor TKs: Egfr, Breathless and Pvr. Reducing the activity of any of the three kinases by tracheal expression of dominant-negative mutants suppresses cyst formation. By competing dominant-negative and constitutively active kinase mutants against each other, we show that the three RTKs have partially interchangeable activities, so that increasing the activity of one kinase can compensate for the effects of reducing the activity of another. This implies that SH2-domain downstream effectors that are required for the phenotype are likely to be able to interact with phosphotyrosine sites on all three receptor TKs. We also show that the phenotype involves increases in signaling through the MAP kinase and Rho GTPase pathways.

  8. Dual silencing of insulin-like growth factor-I receptor and epidermal growth factor receptor in colorectal cancer cells is associated with decreased proliferation and enhanced apoptosis.

    Science.gov (United States)

    Kaulfuss, Silke; Burfeind, Peter; Gaedcke, Jochen; Scharf, Jens-Gerd

    2009-04-01

    Overexpression and activation of tyrosine kinase receptors are common features of colorectal cancer. Using the human colorectal cancer cell lines DLD-1 and Caco-2, we evaluated the role of the insulin-like growth factor-I (IGF-I) receptor (IGF-IR) and epidermal growth factor receptor (EGFR) in cellular functions of these cells. We used the small interfering RNA (siRNA) technology to specifically down-regulate IGF-IR and EGFR expression. Knockdown of IGF-IR and EGFR resulted in inhibition of cell proliferation of DLD-1 and Caco-2 cells. An increased rate of apoptosis was associated with siRNA-mediated silencing of IGF-IR and EGFR as assessed by activation of caspase-3/caspase-7. The combined knockdown of both EGFR and IGF-IR decreased cell proliferation and induced cell apoptosis more effectively than did silencing of either receptor alone. Comparable effects on cell proliferation and apoptosis were observed after single and combinational treatment of cells by the IGF-IR tyrosine kinase inhibitor NVP-AEW541 and/or the EGFR tyrosine kinase inhibitor erlotinib. Combined IGF-IR and EGFR silencing by either siRNAs or tyrosine kinase inhibitors diminished the phosphorylation of downstream signaling pathways AKT and extracellular signal-regulated kinase (ERK)-1/2 more effectively than did the single receptor knockdown. Single IGF-IR knockdown inhibited IGF-I-dependent phosphorylation of AKT but had no effect on IGF-I- or EGF-dependent phosphorylation of ERK1/2, indicating a role of EGFR in ligand-dependent ERK1/2 phosphorylation. The present data show that inhibition of the IGF-IR transduction cascade augments the antipoliferative and proapoptotic effects of EGFR inhibition in colorectal cancer cells. A clinical application of combination therapy targeting both EGFR and IGF-IR could be a promising therapeutic strategy.

  9. An Integrated Model of Epidermal Growth Factor Receptor Trafficking and Signal Transduction

    Energy Technology Data Exchange (ETDEWEB)

    Resat, Haluk; Ewald, Jonathan A.; Dixon, David A.; Wiley, H. S.

    2003-08-01

    Endocytic trafficking of many types of receptors can have profound effects on subsequent signaling events. Quantitative models of these processes, however, have usually considered trafficking and signaling independently. Here, we present an integrated model of both the trafficking and signaling pathway of the epidermal growth factor receptor (EGFR) using a probability weighted-dynamic Monte Carlo simulation. Our model consists of hundreds of distinct endocytic compartments and about 13,000 reactions/events that occur over a broad spatio-temporal range. By using a realistic multi-compartment model, we can investigate the distribution of the receptors among cellular compartments as well as their potential signal transduction characteristics. Our new model also allows the incorporation of physio-chemical aspects of ligand-receptor interactions, such as pH-dependent binding in different endosomal compartments. To determine the utility of this approach, we simulated the differential activation of the EGFR by two of its ligands, epidermal growth factor (EGF) and transforming growth factor- alpha (TGF-a). Our simulations predict that when EGFR is activated with TGF-a, receptor activation is biased toward the cell surface whereas EGF produces a signaling bias towards the endosomal compartment. Experiments confirm these predictions from our model and simulations. Our model accurately predicts the kinetics and extent of receptor down-regulation induced by either EGF or TGF-a. Our results suggest that receptor trafficking controls the compartmental bias of signal transduction, rather than simply modulating signal magnitude. Our model provides a new approach to evaluating the complex effect of receptor trafficking on signal transduction. Importantly, the stochastic and compartmental nature of the simulation allows these models to be directly tested by high-throughput approaches, such as quantitative image analysis.

  10. Growth factor receptors and related signalling pathways as targets for novel treatment strategies of hepatocellular cancer

    Institute of Scientific and Technical Information of China (English)

    Michael Hopfner; Detlef Schuppan; Hans Scherübl

    2008-01-01

    Growth factors and their corresponding receptors are commonly overexpressed and/or dysregulated in many cancers including hepatocellular cancer (HCC). Clinical trials indicate that growth factor receptors and their related signalling pathways play important roles in HCC cancer etiology and progression, thus providing rational targets for innovative cancer therapies. A number of strategies including monoclonal antibodies, tyrosine kinase inhibitors ("small molecule inhibitors") and antisense oligonucleotides have already been evaluated for their potency to inhibit the activity and downstream signalling cascades of these receptors in HCC. First clinical trials have also shown that multi-kinase inhibition is an effective novel treatment strategy in HCC. In this respect sorafenib, an inhibitor of Raf-, VEGF- and PDGF-signalling, is the first multi-kinase inhibitor that has been approved by the FDA for the treatment of advanced HCC. Moreover, the serine-threonine kinase of mammalian target of rapamycin (mTOR) upon which the signalling of several growth factor receptors converge plays a central role in cancer cell proliferation, mTOR inhibition of HCC is currently also being studied in preclinical trials. As HCCs represent hypervascularized neoplasms, inhibition of tumour vessel formation via interfering with the VEGF/VEGFR system is another promising approach in HCC treatment. This review will summarize the current status of the various growth factor receptor-based treatment strategies and in view of the multitude of novel targeted approaches, the rationale for combination therapies for advanced HCC treatment will also be taken into account.

  11. Circulating TNF receptors are significant prognostic biomarkers for idiopathic membranous nephropathy.

    Directory of Open Access Journals (Sweden)

    Su Mi Lee

    Full Text Available Idiopathic membranous nephropathy (iMN is a common cause of nephrotic syndrome in adults. A biomarker to accurately indicate the severity of iMN and predict long-term prognosis is insufficient. Here, we evaluated the clinical significance of circulating tumor necrosis factor receptors (cTNFRs as prognostic biomarkers of iMN with nephrotic syndrome. A total of 113 patients with biopsy-proven iMN and 43 healthy volunteers were enrolled in this study. Ninety patients with iMN had nephrotic range proteinuria. Levels of cTNFRs were measured by using serum samples collected at the time of initial diagnosis. Levels of cTNFRs were higher in the patients with nephrotic syndrome than in those with subnephrotic range proteinuria or in the healthy volunteers (P for trend <0.001. Estimated glomerular filtration rate and proteinuria tended to worsen as the cTNFRs levels increased. Having a cTNFR1 level within the highest tertile was a significant risk factor for renal progression after adjustment, in comparison with the other tertiles (hazard ratio [HR], 3.39; 95% confidence interval [95% CI], 1.48-7.78; P = 0.004. The cTNFR2 level within the highest tertile also significantly increased the risk of renal progression (HR, 3.29; 95% CI, 1.43-7.54; P = 0.005. Renal tubular TNFRs expression was associated with cTNFRs level. However, the cTNFRs levels were not associated with autoantibody against phospholipase A2 receptor reactivity/levels or treatment response. This study demonstrated that cTNFRs levels at the time of initial diagnosis could predict renal progression in patients with iMN.

  12. GATA Factor-G-Protein-Coupled Receptor Circuit Suppresses Hematopoiesis

    Directory of Open Access Journals (Sweden)

    Xin Gao

    2016-03-01

    Full Text Available Hematopoietic stem cells (HSCs originate from hemogenic endothelium within the aorta-gonad-mesonephros (AGM region of the mammalian embryo. The relationship between genetic circuits controlling stem cell genesis and multi-potency is not understood. A Gata2 cis element (+9.5 enhances Gata2 expression in the AGM and induces the endothelial to HSC transition. We demonstrated that GATA-2 rescued hematopoiesis in +9.5−/− AGMs. As G-protein-coupled receptors (GPCRs are the most common targets for FDA-approved drugs, we analyzed the GPCR gene ensemble to identify GATA-2-regulated GPCRs. Of the 20 GATA-2-activated GPCR genes, four were GATA-1-activated, and only Gpr65 expression resembled Gata2. Contrasting with the paradigm in which GATA-2-activated genes promote hematopoietic stem and progenitor cell genesis/function, our mouse and zebrafish studies indicated that GPR65 suppressed hematopoiesis. GPR65 established repressive chromatin at the +9.5 site, restricted occupancy by the activator Scl/TAL1, and repressed Gata2 transcription. Thus, a Gata2 cis element creates a GATA-2-GPCR circuit that limits positive regulators that promote hematopoiesis.

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

    Science.gov (United States)

    Kyakumoto, S; Kurokawa, R; Ota, M

    1990-07-12

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

  14. Effects of (-)-Epigallocatechin gallate on some protein factors involved in the epidermal growth factor receptor signaling pathway

    Institute of Scientific and Technical Information of China (English)

    Yinjiu Huang; Ruiqing Xu; Baoan Song; Song Yang; Li Zhao; Shouwei Wua

    2009-01-01

    (-)-Epigallocatechin gallate (EGCG), a major polyphenolic constituent of green tea, can inhibit activity of specific receptor tyrosine kinases (RTKs) and related downstream signal transduction pathways, resulting in the control of unwanted cell proliferation. The epidermal growth factor receptor (EGFR) signaling pathway is one of the most important pathways that regulates growth, survival, proliferation and differentiation in mammalian cells. This review addresses the effects of EGCG on some protein factors involved in the EGFR signaling pathway in a direct or indirect manner. Based on our understanding of the interaction between EGCG and these factors, and based on their structures, EGCG could be used as a lead compound for designing and synthesizing novel drugs with significant biological activity.

  15. Receptors for T cell-replacing factor/interleukin 5. Specificity, quantitation, and its implication

    OpenAIRE

    1988-01-01

    T cell-replacing factor (TRF)/IL-5 is a glycosylated polypeptide that acts as a key factor for B cell growth and differentiation. Since IL-5 action is probably mediated by specific cell surface receptor(s), we have characterized the binding of IL-5 to cells using biosynthetically [35S]methionine-labeled IL-5 and 125I-IL-5 that had been prepared using Bolton-Hunter reagent. The radiolabeled IL-5 binds specifically to BCL1- B20 (in vitro line) (a murine chronic B cell leukemic cell line previou...

  16. ErbB2 resembles an autoinhibited invertebrate epidermal growth factor receptor

    Energy Technology Data Exchange (ETDEWEB)

    Alvarado, Diego; Klein, Daryl E.; Lemmon, Mark A.; (UPENN-MED)

    2009-09-25

    The orphan receptor tyrosine kinase ErbB2 (also known as HER2 or Neu) transforms cells when overexpressed, and it is an important therapeutic target in human cancer. Structural studies have suggested that the oncogenic (and ligand-independent) signalling properties of ErbB2 result from the absence of a key intramolecular 'tether' in the extracellular region that autoinhibits other human ErbB receptors, including the epidermal growth factor (EGF) receptor. Although ErbB2 is unique among the four human ErbB receptors, here we show that it is the closest structural relative of the single EGF receptor family member in Drosophila melanogaster (dEGFR). Genetic and biochemical data show that dEGFR is tightly regulated by growth factor ligands, yet a crystal structure shows that it, too, lacks the intramolecular tether seen in human EGFR, ErbB3 and ErbB4. Instead, a distinct set of autoinhibitory interdomain interactions hold unliganded dEGFR in an inactive state. All of these interactions are maintained (and even extended) in ErbB2, arguing against the suggestion that ErbB2 lacks autoinhibition. We therefore suggest that normal and pathogenic ErbB2 signalling may be regulated by ligands in the same way as dEGFR. Our findings have important implications for ErbB2 regulation in human cancer, and for developing therapeutic approaches that target novel aspects of this orphan receptor.

  17. Developmentally Regulated Expression of the Nerve Growth Factor Receptor Gene in the Periphery and Brain

    Science.gov (United States)

    Buck, C. R.; Martinez, Humberto J.; Black, Ira B.; Chao, Moses V.

    1987-05-01

    Nerve growth factor (NGF) regulates development and maintenance of function of peripheral sympathetic and sensory neurons. A potential role for the trophic factor in brain has been detected only recently. The ability of a cell to respond to NGF is due, in part, to expression of specific receptors on the cell surface. To study tissue-specific expression of the NGF receptor gene, we have used sensitive cRNA probes for detection of NGF receptor mRNA. Our studies indicate that the receptor gene is selectively and specifically expressed in sympathetic (superior cervical) and sensory (dorsal root) ganglia in the periphery, and by the septum-basal forebrain centrally, in the neonatal rat in vivo. Moreover, examination of tissues from neonatal and adult rats reveals a marked reduction in steady-state NGF receptor mRNA levels in sensory ganglia. In contrast, a 2- to 4-fold increase was observed in the basal forebrain and in the sympathetic ganglia over the same time period. Our observations suggest that NGF receptor mRNA expression is developmentally regulated in specific areas of the nervous system in a differential fashion.

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

    DEFF Research Database (Denmark)

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

    1992-01-01

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

  19. Ric-8A, a Gα protein guanine nucleotide exchange factor potentiates taste receptor signaling

    Directory of Open Access Journals (Sweden)

    Claire J Fenech

    2009-10-01

    Full Text Available Taste receptors for sweet, bitter and umami tastants are G-protein coupled receptors (GPCRs. While much effort has been devoted to understanding G-protein-receptor interactions and identifying the components of the signalling cascade downstream of these receptors, at the level of the G-protein the modulation of receptor signal transduction remains relatively unexplored. In this regard a taste-specific regulator of G-protein signaling (RGS, RGS21, has recently been identified. To study whether guanine nucleotide exchange factors (GEFs are involved in the transduction of the signal downstream of the taste GPCRs we investigated the expression of Ric-8A and Ric-8B in mouse taste cells and their interaction with G-protein subunits found in taste buds. Mammalian Ric-8 proteins were initially identified as potent GEFs for a range of Gα subunits and Ric-8B has recently been shown to amplify olfactory signal transduction. We find that both Ric-8A and Ric-8B are expressed in a large portion of taste bud cells and that most of these cells contain IP3R-3 a marker for sweet, umami and bitter taste receptor cells. Ric-8A interacts with Gα-gustducin and Gαi2 through which it amplifies the signal transduction of hTas2R16, a receptor for bitter compounds. Overall, these findings are consistent with a role for Ric-8 in mammalian taste signal transduction.

  20. Expression of vascular endothelial growth factor and its two receptors in normal human endometrium

    Institute of Scientific and Technical Information of China (English)

    王海燕; 陈贵安

    2003-01-01

    Objectives: We try to demonstrate the expression of vascular endothelial growthfactor (VEGF) and its receptors, flt-1 and KDR, in normal human emdometrium duringthe menstrual cycle.Methods: Immunohistochemical method was used to observe the expression ofVEGF and its two receptors in emdometrium throughout the normal menstrual cyclemeanwhile the isoforms of VEGF were also detected by Western blot analysis. The en-dothelial cells of micro-vessels were marked with Ⅷ factor antibody.Results: VEGF and its receptors existed in endometrial glandular, stromal and vas-cular endothelial cells of human endometrium. Their expressions were higher in the mid-secretory phase of menstrual cycle and highest at menstruation. VEGF121 and VEGF165were the predominant isoforms in normal human endometrium.Conclusion: The expression of VEGF and its two receptors showed cycle-dependentin human endometrium, probably involved in embryonic implantation and endometrialproliferation and differentiation.

  1. Cross-talk between the calcium-sensing receptor and the epidermal growth factor receptor in Rat-1 fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Tomlins, Scott A.; Bollinger, Nikki; Creim, Jeffrey A.; Rodland, Karin D.

    2005-08-15

    The calcium-sensing receptor (CaR) is a G-protein coupled receptor that is activated by extracellular calcium (Ca2+o). Rat-1 fibroblasts have been shown to proliferate and increase ERK activity in response to elevation of [Ca2+]o, and these responses are dependent on functional CaR expression. In this report, we examined the role of cross-talk between the CaR and the epidermal growth factor receptor (EGFR) in mediating these responses in Rat-1 cells. This report shows that AG1478, a specific inhibitor of the EGFR kinase, significantly inhibits the increase in proliferation induced by elevated Ca2+o. Further, we show that AG1478 acts downstream or separately from G-protein subunit activation of phospholipase C. AG1478 significantly inhibits Ca2+o-stimulated ERK phosphorylation and in vitro kinase activity. A similar inhibition of ERK phosphorylation was observed in response to the inhibitor AG494. In addition, treatment with inhibitors of metalloproteases involved in shedding of membrane anchored EGF family ligands substantially inhibited the increase in ERK activation in response to elevated Ca2+o. This is consistent with the known expression of TGFa by Rat-1 cells. These results indicate that EGFR transactivation is an important component of the CaR mediated response to increased Ca2+o in Rat-1 fibroblasts, and most likely involves CaR-mediated induction of regulated proteolysis and ligand shedding.

  2. Epidermal Growth Factor Receptor Expression in Triple Negative and Nontriple Negative Breast Carcinomas.

    Science.gov (United States)

    Changavi, Arathi A; Shashikala, Arundhathi; Ramji, Ashwini S

    2015-01-01

    The panel of markers used for molecular classification include estrogen receptors (ER), progesterone receptors (PR), human epidermal growth factor receptor (HER)-2/neu, p53, Bcl-2 and basal markers like cytokeratin 5/6 or epidermal growth factor receptor (EGFR). Among these, EGFR plays an important role and is associated with bad prognosis. To study EGFR expression in triple negative breast carcinoma (TNBC) and non-TNBCs (NTNBCs). Fifty cases of breast carcinomas were classified and graded according to World Health Organization and Nottingham modification of Scarff-Bloom-Richardson (SBR) system, respectively. The age of the patients ranged from 28 to 69 years. Histological features such as necrosis, pushing borders, lymphocytic infiltrate and periductal elastosis were noted. The panel of markers used in our study included ER, PR, HER-2/neu and EGFR. EGFR expression was assessed based on membrane staining. Chi-square test was applied for statistical analysis to compare EGFR expression with hormonal status and prognostic factors. P triple negative and strongly expressed EGFR. EGFR expression was inversely associated with ER status and showed strong association with necrosis and lymphocytic infiltrate, but not with pushing border and periductal elastosis. EGFR is an important marker to stratify patients with breast cancer according to molecular classification. Its expression correlated positively with young age, higher SBR grade, necrosis, lymphocytic infiltrate and inversely with hormonal receptor expression.

  3. TNF-α has tropic rather than apoptotic activity in human hematopoietic progenitors: involvement of TNF receptor-1 and caspase-8.

    Science.gov (United States)

    Mizrahi, Keren; Stein, Jerry; Yaniv, Isaac; Kaplan, Offer; Askenasy, Nadir

    2013-01-01

    Tumor necrosis factor-α (TNF-α) has been suggested to exert detrimental effects on hematopoietic progenitor function that might limit the success of transplants. In this study, we assessed the influences of TNF-α and its two cognate receptors on the function of fresh umbilical cord blood (UCB) and cryopreserved mobilized peripheral blood (mPB). CD34(+) progenitors from both sources are less susceptible to spontaneous apoptosis than lineage-committed cells and are not induced into apoptosis by TNF-α. Consequently, the activity of UCB-derived severe combined immune deficiency (SCID) reconstituting cells and long-term culture-initiating cells is unaffected by this cytokine. On the contrary, transient exposure of cells from both sources to TNF-α stimulates the activity of myeloid progenitors, which persists in vivo in UCB cell transplants. Progenitor stimulation is selectively mediated by TNF-R1 and involves activation of caspase-8, without redundant activity of TNF-R2. Despite significant differences between fresh UCB cells and cryopreserved mPB cells in susceptibility to apoptosis and time to activation, TNF-α is primarily involved in tropic signaling in hematopoietic progenitors from both sources. Cytokine-mediated tropism cautions against TNF-α neutralization under conditions of stress hematopoiesis and may be particularly beneficial in overcoming the limitations of UCB cell transplants.

  4. Expression of type 1 corticotropin-releasing factor receptor in the guinea pig enteric nervous system.

    Science.gov (United States)

    Liu, Sumei; Gao, Xiang; Gao, Na; Wang, Xiyu; Fang, Xiucai; Hu, Hong-Zhen; Wang, Guo-Du; Xia, Yun; Wood, Jackie D

    2005-01-17

    Reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemistry, electrophysiological recording, and intraneuronal injection of the neuronal tracer biocytin were integrated in a study of the functional expression of corticotropin-releasing factor (CRF) receptors in the guinea pig enteric nervous system. RT-PCR revealed expression of CRF1 receptor mRNA, but not CRF2, in both myenteric and submucosal plexuses. Immunoreactivity for the CRF1 receptor was distributed widely in the myenteric plexus of the stomach and small and large intestine and in the submucosal plexus of the small and large intestine. CRF1 receptor immunoreactivity was coexpressed with calbindin, choline acetyltransferase, and substance P in the myenteric plexus. In the submucosal plexus, CRF1 receptor immunoreactivity was found in neurons that expressed calbindin, substance P, choline acetyltransferase, or neuropeptide Y. Application of CRF evoked slowly activating depolarizing responses associated with elevated excitability in both myenteric and submucosal neurons. Histological analysis of biocytin-filled neurons revealed that both uniaxonal neurons with S-type electrophysiological behavior and neurons with AH-type electrophysiological behavior and Dogiel II morphology responded to CRF. The CRF-evoked depolarizing responses were suppressed by the CRF1/CRF2 receptor antagonist astressin and the selective CRF1 receptor antagonist NBI27914 and were unaffected by the selective CRF2 receptor antagonist antisauvagine-30. The findings support the hypothesis that the CRF1 receptor mediates the excitatory actions of CRF on neurons in the enteric nervous system. Actions on enteric neurons might underlie the neural mechanisms by which stress-related release of CRF in the periphery alters intestinal propulsive motor function, mucosal secretion, and barrier functions.

  5. Platelet-derived growth factor receptor-β in myocyte was upregulated by angiotensin II

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    To observe the regulation of platelet-derived growth factor (PDGF) receptor-βin myocyte stimulated by angiotensin II (AngII) at both integrated and cellular levels and reveal the signal transduction mechanism in cell, two kidneys, one clip (2K1C) renal hypertension were performed by placing a sliver clip around the left renal artery. Blood pressure and the ratio of left ventricular weight to body weight were measured at 4 and 8 weeks after operation. The content of AngII in heart was detected by radioimmunology assay; the protein level of PDGF receptor-βin heart was measured by Western blot analysis. The alteration of PDGF receptor-βstimulated by AngII and several inhibitors was observed on cultured neonatal rat ventricular myocyte (NRVM). The content of AngII in heart of 2K1C renal hypertensive rat at 4 and 8 weeks after operation was increased. Compared with sham group, 4 and 8 weeks after operation, PDGF receptor-βin heart of 2K1C group was upregulated by 100.3% and 127.1% (P < 0.05), respectively. This upregulation could be inhibited by captopril. For cultured myocyte, PDGF receptor-βwas increased by 47.1% after being stimulated by AngII and this upregulation could be inhibited by losartan which was an inhibitor of AT1 receptor. PLC inhibitor (U73122) and MEK inhibitor (PD98059) could partly inhibit PDGF receptor-βupregulation induced by AngII. These results suggested that AngII could upregulate PDGF receptor-βin myocyte by its AT1 receptor and this effect was at least partly dependent on PLC and extracellular signal-regulated kinase (ERK).

  6. Prostaglandin E2 regulates angiogenesis via activation of fibroblast growth factor receptor-1.

    Science.gov (United States)

    Finetti, Federica; Solito, Raffaella; Morbidelli, Lucia; Giachetti, Antonio; Ziche, Marina; Donnini, Sandra

    2008-01-25

    Prostaglandin E(2) (PGE(2)) behaves as a mitogen in epithelial tumor cells as well as in many other cell types. We investigated the actions of PGE(2) on microvascular endothelial cells (capillary venular endothelial cells) with the purpose of delineating the signaling pathway leading to the acquisition of the angiogenic phenotype and to new vessel formation. PGE(2) (100 nM) produced activation of the fibroblast growth factor receptor 1 (FGFR-1), as measured by its phosphorylation, but not of vascular endothelial growth factor receptor 2. PGE(2) stimulated the EP3 subtype receptor, as deduced by abrogation of EP3 Galpha(i) subunit activity through pertussis toxin. Consistent with this result, in human umbilical venular endothelial cells missing the EP3 receptor, PGE(2) did not phosphorylate FGFR-1. Upon binding to its receptor, PGE(2) initiated an autocrine/paracrine signaling cascade involving the intracellular activation of c-Src, activation of matrix metalloproteinase (predominantly MMP2), which in turn caused the mobilization of membrane-anchored fibroblast growth factor-2 (FGF-2). In fact, in cells unable to release FGF-2 the transfection with both FGFR-1 and EP3 did not result in FGFR-1 phosphorylation in response to PGE(2). Relevance for the FGF2-FGFR-1 system was highlighted by confocal analysis, showing receptor internalization after cell exposure to the prostanoid. ERK1/2 appeared to be the distal signal involved, its phosphorylation being sensitive to either cSrc inhibitor or FGFR-1 blocker. Finally, PGE(2) stimulated cell migration and capillary formation in aortic rings, which were severely reduced by inhibitors of signaling molecules or by receptor antagonist. In conclusion, this study provides evidence for the involvement of FGFR-1 through FGF2 in eliciting PGE(2) angiogenic responses. This signaling pattern is similar to the autocrine-paracrine mechanism which operates in endothelial cells to support neovascular growth.

  7. Kinetics of the Attachment of Intrinsic Factor-Bound Cobamides to Ileal Receptors

    Science.gov (United States)

    Mathan, V. I.; Babior, Bernard M.; Donaldson, Robert M.

    1974-01-01

    To determine whether the molecular configuration of vitamin B12 influences the attachment of intrinsic factor-vitamin B12 complex to ileal microvillous membrane receptor sites, we have examined the kinetics of uptake of intrinsic factor-bound cyanocobalamin by brush borders and microvillous membranes isolated from guinea pig ileum, and have compared this uptake with that of intrinsic factor alone and with that of intrinsic factor complexed with various analogs of cyanocobalamin. We first studied the kinetics of binding of cyanocobalamin and other cobamides to human gastric intrinsic factor. The binding of cyanocobalamin showed saturation kinetics and, at relatively high concentrations of cyanocobalamin, a Scatchard plot of binding was linear. The dissociation constant for the intrinsic factor-cyanocobalamin complex was 0.066 nM. When the binding of various vitamin B12 analogs to intrinsic factor was determined by competition experiments, the analogs could be separated into two categories: those with affinities similar to that of cyanocobalamin and those with affinities much lower than that of cyanocobalamin. The affinity of cyanocobalamin for intrinsic factor was not altered by various substitutions at the -CN position, while removal of a single amido group on the corrin ring of substitution of the dimethylbenzimidazole base greatly reduced affinity. Removal of the base totally abolished binding. These findings, confirming those reported by others, are consistent with the concept that the cyanocobalamin molecule fits into a “pocket” in the intrinsic factor molecule, with the nucleotide base facing inward and the -CN side of the planar corrin ring facing outward. We then investigated the attachment of intrinsic factor-bound cyanocobalamin to ileal receptor. Attachment to microvillous membranes showed saturation kinetics with a dissociation constant of 0.25 nM. Attachment was rapid and was 70% complete within 5 min; the second-order rate constant for attachment

  8. Differential requirement of the epidermal growth factor receptor for G protein-mediated activation of transcription factors by lysophosphatidic acid

    Directory of Open Access Journals (Sweden)

    Dent Paul

    2010-01-01

    Full Text Available Abstract Background The role of the epidermal growth factor receptor (EGFR and other receptor tyrosine kinases (RTKs in provoking biological actions of G protein-coupled receptors (GPCRs has been one of the most disputed subjects in the field of GPCR signal transduction. The purpose of the current study is to identify EGFR-mediated mechanisms involved in activation of G protein cascades and the downstream transcription factors by lysophosphatidic acid (LPA. Results In ovarian cancer cells highly responsive to LPA, activation of AP-1 by LPA was suppressed by inhibition of EGFR, an effect that could be reversed by co-stimulation of another receptor tyrosine kinase c-Met with hepatocyte growth factor, indicating that LPA-mediated activation of AP-1 requires activity of a RTK, not necessarily EGFR. Induction of AP-1 components by LPA lied downstream of Gi, G12/13, and Gq. Activation of the effectors of Gi, but not Gq or G12/13 was sensitive to inhibition of EGFR. In contrast, LPA stimulated another prominent transcription factor NF-κB via the Gq-PKC pathway in an EGFR-independent manner. Consistent with the importance of Gi-elicited signals in a plethora of biological processes, LPA-induced cytokine production, cell proliferation, migration and invasion require intact EGFR. Conclusions An RTK activity is required for activation of the AP-1 transcription factor and other Gi-dependent cellular responses to LPA. In contrast, activation of G12/13, Gq and Gq-elicited NF-κB by LPA is independent of such an input. These results provide a novel insight into the role of RTK in GPCR signal transduction and biological functions.

  9. The heparan sulfate co-receptor and the concentration of fibroblast growth factor-2 independently elicit different signalling patterns from the fibroblast growth factor receptor

    Directory of Open Access Journals (Sweden)

    Duchesne Laurence

    2010-06-01

    Full Text Available Abstract Background The fibroblast growth factor receptor (FGFR interprets concentration gradients of FGF ligands and structural changes in the heparan sulfate (HS co-receptor to generate different cellular responses. However, whether the FGFR generates different signals is not known. Results We have previously shown in rat mammary fibroblasts that in cells deficient in sulfation, and so in HS co-receptor, FGF-2 can only stimulate a transient phosphorylation of p42/44 MAPK and so cannot stimulate DNA synthesis. Here we demonstrate that this is because in the absence of HS, FGF-2 fails to stimulate the phosphorylation of the adaptor FGFR substrate 2 (FRS2. In cells possessing the HS co-receptor, FGF-2 elicits a bell-shaped dose response: optimal concentrations stimulate DNA synthesis, but supramaximal concentrations (≥ 100 ng/mL have little effect. At optimal concentrations (300 pg/mL FGF-2 stimulates a sustained dual phosphorylation of p42/44 MAPK and tyrosine phosphorylation of FRS2. In contrast, 100 ng/mL FGF-2 only stimulates a transient early peak of p42/44 MAPK phosphorylation and fails to stimulate appreciably the phosphorylation of FRS2 on tyrosine. Conclusions These results suggest that the nature of the FGFR signal produced is determined by a combination of the HS co-receptor and the concentration of FGF ligand. Both the phosphorylation of the adaptor FRS2, the kinetics (sustained or transient of phosphorylation of p42/44(MAPK are varied, and so differing cellular responses are produced.

  10. Modified epidermal growth factor receptor (EGFR-bearing liposomes (MRBLs are sensitive to EGF in solution.

    Directory of Open Access Journals (Sweden)

    Albert Wong

    Full Text Available Cancers often overexpress EGF and other growth factors to promote cell replication and migration. Previous work has not produced targeted drug carriers sensitive to abnormal amounts of growth factors. This work demonstrates that liposomes bearing EGF receptors covalently crosslinked to p-toluic acid or methyl-PEO(4-NHS ester (or, in short, MRBLs exhibit an increased rate of release of encapsulated drug compounds when EGF is present in solution. Furthermore, the modified EGF receptors retain the abilities to form dimers in the presence of EGF and bind specifically to EGF. These results demonstrate that MRBLs are sensitive to EGF in solution and indicate that MRBL-reconstituted modified EGF receptors, in the presence of EGF in solution, form dimers which increase MRBL permeability to encapsulated compounds.

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

    DEFF Research Database (Denmark)

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

    2010-01-01

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

  12. The neural cell adhesion molecule binds to fibroblast growth factor receptor 2

    DEFF Research Database (Denmark)

    Christensen, Claus; Lauridsen, Jes B; Berezin, Vladimir;

    2006-01-01

    The neural cell adhesion molecule (NCAM) can bind to and activate fibroblast growth factor receptor 1 (FGFR1). However, there are four major FGFR isoforms (FGFR1-FGFR4), and it is not known whether NCAM also interacts directly with the other three FGFR isoforms. In this study, we show by surface...

  13. Endoglin structure and function - Determinants of endoglin phosphorylation by transforming growth factor-beta receptors

    NARCIS (Netherlands)

    Koleva, Rositsa I.; Conley, Barbara A.; Romero, Diana; Riley, Kristin S.; Marto, Jarrod A.; Lux, Andreas; Vary, Calvin P. H.

    2006-01-01

    Determination of the functional relationship between the transforming growth factor-beta(TGF beta) receptor proteins endoglin and ALK1 is essential to the understanding of the human vascular disease, hereditary hemorrhagic telangiectasia. TGF beta 1 caused recruitment of ALK1 into a complex with end

  14. The insulin-like growth factor 1 receptor in cancer : Old focus, new future

    NARCIS (Netherlands)

    Hartog, Hermien; Wesseling, Jelle; Boezen, H. Marike; van der Graaf, Winette T. A.

    2007-01-01

    The importance of insulin-like growth factor 1 receptor (IGF-1R) signalling in malignant behaviour of tumour cells is well established. Currently, development of drugs targeting the IGF-1R as anticancer treatment is emerging. Several IGF-1R targeting strategies are being investigated in phases I and

  15. The insulin-like growth factor 1 receptor in cancer : Old focus, new future

    NARCIS (Netherlands)

    Hartog, Hermien; Wesseling, Jelle; Boezen, H. Marike; van der Graaf, Winette T. A.

    2007-01-01

    The importance of insulin-like growth factor 1 receptor (IGF-1R) signalling in malignant behaviour of tumour cells is well established. Currently, development of drugs targeting the IGF-1R as anticancer treatment is emerging. Several IGF-1R targeting strategies are being investigated in phases I and

  16. The insulin-like growth factor 1 receptor in cancer: old focus, new future.

    NARCIS (Netherlands)

    Hartog, H. de; Wesseling, J.; Boezen, H.M.; Graaf, W.T.A. van der

    2007-01-01

    The importance of insulin-like growth factor 1 receptor (IGF-1R) signalling in malignant behaviour of tumour cells is well established. Currently, development of drugs targeting the IGF-1R as anticancer treatment is emerging. Several IGF-1R targeting strategies are being investigated in phases I and

  17. Effect of fluoride on expression of insulinlike growth factor-1 and its receptor of rat osteoblasts

    Institute of Scientific and Technical Information of China (English)

    喻茂娟

    2013-01-01

    Objective To explore the influence of fluorine on mRNA and protein expression of the insulin-like growth factor-1 (IGF-1) and its receptor of rat osteoblasts.Methods Osteoblasts were isolated from rat bone by enzyme digestion.Different fluorine concentration[0 (con-

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

    DEFF Research Database (Denmark)

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

    2014-01-01

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

  19. Structural basis for receptor recognition of vitamin-B(12)-intrinsic factor complexes

    DEFF Research Database (Denmark)

    Andersen, Christian Brix Folsted; Madsen, Mette; Storm, Tina;

    2010-01-01

    Cobalamin (Cbl, vitamin B(12)) is a bacterial organic compound and an essential coenzyme in mammals, which take it up from the diet. This occurs by the combined action of the gastric intrinsic factor (IF) and the ileal endocytic cubam receptor formed by the 460-kilodalton (kDa) protein cubilin...

  20. Orphan nuclear receptor TR4 and fibroblast growth factor 1 in metabolism

    NARCIS (Netherlands)

    Liu, Weilin

    2016-01-01

    Metabolic homeostasis is achieved, in part, through the coordinated activities of members of the Nuclear Receptor (NR) family, a superfamily of ligand-modulated transcription factors (TFs) that mediate responses to a wide range of lipophilic signaling molecules including lipids, steroids, retinoids,

  1. Localization and functional roles of corticotropin-releasing factor receptor type 2 in the cerebellum

    NARCIS (Netherlands)

    Gounko, Natalia V.; Gramsbergen, Albert; van der Want, Johannes J. L.

    2008-01-01

    The corticotropin-releasing factor (CRF) type 2 receptor has three splice variants alpha, beta, and gamma. In the rodent brain only CRF-R2 alpha is present. In the cerebellum, CRF-R2 alpha has two different isoforms: a full-length form (fl) and truncated (tr). Both forms CRF-R2 have a unique cellula

  2. Epidermal growth factor receptor expression in pancreatic lesions induced in the rat by azaserine

    NARCIS (Netherlands)

    Visser, C.J.T.; Weger, R.A. de; Blokland, W.T.M. van; Seifert-Bock, I.; Kobrin, M.S.; Korc, M.; Woutersen, R.A.

    1996-01-01

    In the present study, the expression of the epidermal growth factor receptor (EGFR) was investigated in putative preneoplastic and neoplastic acinar cell lesions induced in the rat pancreas by azaserine, using Northern blotting, in situ hybridisation (ISH) and immunohistochemistry. EGFR protein leve

  3. Solubilization of nerve growth factor receptors of rabbit superior cervical ganglia.

    Science.gov (United States)

    Banerjee, S P; Cuatrecasas, P; Snyder, S H

    1976-09-25

    Nerve growth factor (NGF) receptors of rabbit superior cervical ganglia can be solubilized by treatment with detergents and readily assayed in the soluble state. Triton X-100 and deoxycholate reduce specific binding of NGF to ganglia membranes. In membranes treated with Triton X-100 (0.5 to 2.0%) the reduction in NGF binding by membranes is accompanied by a corresponding increase in binding in the supernatant fluid. NGF binding in soluble preparations can be rapidly assayed by precipitating NGF bound to receptors with polyethylene glycol under conditions in which unbound NGF is not precipitated. NGF binding to soluble preparations is saturable whether evaluated by the binding of 125I-NGF or by diluting 125I-NGF with native NGF. Using both techniques, the dissociation constant for NGF binding to soluble receptors is about 0.2 nM, the same as its dissociation constant from receptor sites in intact membranes. NGF binding to soluble receptors displays a high degree of peptide specificity, similar to receptor sites in intact membranes of superior cervical ganglia. A method of labeling NGF with 125I-3(4-hydroxyphenyl) propionic acid N-hydroxysuccinimide ester is described which leads to binding properties that are superior to those obtained with previously described 125I-NGF preparations.

  4. Nerve growth factor receptor from rabbit sympathetic ganglia membranes. Relationship between subforms.

    Science.gov (United States)

    Kouchalakos, R N; Bradshaw, R A

    1986-12-05

    The receptor for nerve growth factor (NGF) was purified from Triton X-100 extracts of sympathetic ganglia membranes by affinity chromatography on NGF-Sepharose. Elution of purified receptor was accomplished at pH 5 in the presence of 1 M NaCl. Sodium dodecyl sulfate gel electrophoresis of the purified iodinated receptor showed three major bands at Mr = 126,000, Mr = 105,000, and Mr = 81,000. Affinity labeling of the purified receptor using 125I-NGF and the photoreactive agent N-hydroxysuccinimidyl-p-azidobenzoate resulted in two major cross-linked complexes corresponding to Mr = 135,000 and Mr = 110,000. This labeling pattern is similar to that observed with sympathetic ganglia membranes (Massague, J., Guillette, B. J., Czech, M. P., Morgan, C. J., and Bradshaw, R. A. (1981) J. Biol. Chem. 256, 9419-9424) and indicates that these two forms do not arise from the cross-linking procedure. Reaction of the photoaffinity labeled NGF receptors with increasing amounts of trypsin resulted in a progressive decrease in the high molecular weight complex with a concomitant increase in the low molecular weight form. When the larger complex was isolated by electroelution from a sodium dodecyl sulfate gel and treated with trypsin, a species corresponding to Mr = 100,000 was generated. These observations are best explained by a precursor-product relationship for the two NGF receptor species of sympathetic neurons.

  5. miR-29a suppresses MCF-7 cell growth by downregulating tumor necrosis factor receptor 1.

    Science.gov (United States)

    Zhao, Yiling; Yang, Fenghua; Li, Wenyuan; Xu, Chunyan; Li, Li; Chen, Lifei; Liu, Yancui; Sun, Ping

    2017-02-01

    Tumor necrosis factor receptor 1 is the main receptor mediating many tumor necrosis factor-alpha-induced cellular events. Some studies have shown that tumor necrosis factor receptor 1 promotes tumorigenesis by activating nuclear factor-kappa B signaling pathway, while other studies have confirmed that tumor necrosis factor receptor 1 plays an inhibitory role in tumors growth by inducing apoptosis in breast cancer. Therefore, the function of tumor necrosis factor receptor 1 in breast cancer requires clarification. In this study, we first found that tumor necrosis factor receptor 1 was significantly increased in human breast cancer tissues and cell lines, and knockdown of tumor necrosis factor receptor 1 by small interfering RNA inhibited cell proliferation by arresting the cell cycle and inducing apoptosis. In addition, miR-29a was predicted as a regulator of tumor necrosis factor receptor 1 by TargetScan and was shown to be inversely correlated with tumor necrosis factor receptor 1 expression in human breast cancer tissues and cell lines. Luciferase reporter assay further confirmed that miR-29a negatively regulated tumor necrosis factor receptor 1 expression by binding to the 3' untranslated region. In our functional study, miR-29a overexpression remarkably suppressed cell proliferation and colony formation, arrested the cell cycle, and induced apoptosis in MCF-7 cell. Furthermore, in combination with tumor necrosis factor receptor 1 transfection, miR-29a significantly reversed the oncogenic role caused by tumor necrosis factor receptor 1 in MCF-7 cell. In addition, we demonstrated that miR-29a suppressed MCF-7 cell growth by inactivating the nuclear factor-kappa B signaling pathway and by decreasing cyclinD1 and Bcl-2/Bax protein levels. Taken together, our results suggest that miR-29a is an important regulator of tumor necrosis factor receptor 1 expression in breast cancer and functions as a tumor suppressor by targeting tumor necrosis factor receptor 1 to

  6. Identification and Functional Characterisation of Nod Factor Receptor (NFR) Paralogs in Lotus japonicus

    DEFF Research Database (Denmark)

    Vestergaard, Gitte; Radutoiu, Elena Simona; Stougaard, Jens

    an important missing link in plant-bacterial communication. This picture changed with the cloning of LysM-domain containing receptor-like kinases (LysM-RLKs) in different legume species. In Lotus japonicus, two LysM-RLKs, Nod Factor Receptor 1 (NFR1) and Nod Factor Receptor 5 (NFR5), are believed to bind Nod...... factor, subsequently initiating a signal cascade leading to symbiotic nodule development. Similar genes have also been identified in other plants: seven LysM-domain containing receptor-like kinases (LYKs) were found in the model legume Medicago truncatula, two of them, LYK3 and LYK4 playing a role...

  7. Growth Factor Receptor-Bound Protein 14 Undergoes Light-Dependent Intracellular Translocation in Rod Photoreceptors: Functional Role on Retinal Insulin Receptor Activation

    OpenAIRE

    Rajala, Ammaji; Roger J. Daly; Tanito, Masaki; Allen, Dustin T.; Lowenna J Holt; Lobanova, Ekaterina; Arshavsky, Vadim Y; Rajala, Raju V.S.

    2009-01-01

    Growth factor receptor-bound protein 14 (Grb14) is involved in growth factor receptor tyrosine kinase signaling. Here we report that light causes a major redistribution of Grb14 among the individual subcellular compartments of the retinal rod photoreceptor. Grb14 is localized predominantly to the inner segment, nuclear layer and synapse in dark-adapted rods, whereas in the light-adapted rods, Grb14 redistributed throughout the entire cell, including the outer segment. The translocation of Grb...

  8. TL1A increased IL-6 production on fibroblast-like synoviocytes by preferentially activating TNF receptor 2 in rheumatoid arthritis.

    Science.gov (United States)

    Ma, Zijian; Wang, Bing; Wang, Miaomiao; Sun, Xiaotong; Tang, Yawei; Li, Ming; Li, Fang; Li, Xia

    2016-07-01

    TNF-like protein 1A (TL1A), a member of tumor necrosis factor family, recognized as a ligand of death receptor 3 (DR3) and decoy receptor 3 (DcR3). The interaction of TL1A and DR3 may participate in the pathogenesis of some autoimmune diseases including rheumatoid arthritis (RA). Our previous results showed that high concentrations of TL1A could be found in synovial and serum in RA patients, and it was correlated with disease severity. In addition, TL1A could promote Th17 differentiation induced by TGF-β and IL-6 and increased the production of IL-17A. In the present study, we found that TL1A could promote the expression of IL-6 on fibroblast-like synoviocytes (FLS) of RA patients via NF-κB and JNK signaling pathway. TL1A-stimulated FLS increased the percentage of Th17 of peripheral blood mononuclear cells (PBMC) in RA via the production of IL-6, a critical cytokine involved in the differentiation of Th17. Moreover, the blocking of tumor necrosis factor receptor 2 (TNFR2) decreased TL1A-stimulated IL-6 production by RA FLS. Our results suggest that TL1A was capable of acting on RA FLS to elevate IL-6 expression, which promoted the production of Th17. More importantly, we showed that TL1A could influence RA FLS through binding to TNFR2 rather than DR3 on FLS, which indicated that the treatment of TNF inhibitors not only blocked the TNF but also suppressed the TL1A in RA patients.

  9. Corticotropin-releasing factor receptors and stress-related alterations of gut motor function.

    Science.gov (United States)

    Taché, Yvette; Bonaz, Bruno

    2007-01-01

    Over the past few decades, corticotropin-releasing factor (CRF) signaling pathways have been shown to be the main coordinators of the endocrine, behavioral, and immune responses to stress. Emerging evidence also links the activation of CRF receptors type 1 and type 2 with stress-related alterations of gut motor function. Here, we review the role of CRF receptors in both the brain and the gut as part of key mechanisms through which various stressors impact propulsive activity of the gastrointestinal system. We also examine how these mechanisms translate into the development of new approaches for irritable bowel syndrome, a multifactorial disorder for which stress has been implicated in the pathophysiology.

  10. Association between cadmium and breast cancer risk according to estrogen receptor and human epidermal growth factor receptor 2: epidemiological evidence.

    Science.gov (United States)

    Strumylaite, Loreta; Kregzdyte, Rima; Bogusevicius, Algirdas; Poskiene, Lina; Baranauskiene, Dale; Pranys, Darius

    2014-05-01

    The study aimed to examine the association between cadmium (Cd) and the risk of breast cancer according to estrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2). A hospital-based case-control study was carried out in 585 cases and 1,170 controls. Information on possible risk factors was collected via a structured questionnaire. Urinary Cd was determined by atomic absorption spectrometry. The ER and HER2 levels in tumor tissue were analyzed by immunohistochemistry. Logistic regression was used to calculate odds ratios (ORs) and 95 % confidence intervals (CIs) for breast cancer by creatinine-adjusted urinary Cd. Women with greater creatinine-adjusted urine Cd (3rd quartile: 0.241-0.399 μg/g and 4th quartile: ≥ 0.4 μg/g) experienced 1.6 times higher risk of breast cancer compared with those having Cd concentration lower than 0.147 μg/g (1st quartile) [OR = 1.6, (95 % CI 1.19, 2.17) and OR = 1.62 (95 % CI 1.19, 2.21), respectively, P trend = 0.001] after adjustment for age and other confounders. Both ER+ and HER2- cases from the highest quartile of urine Cd exhibited approximately twice the breast cancer risk of those in the lowest quartile [OR = 1.9, (95 % CI 1.31, 2.74) and OR = 1.87, (95 % CI 1.33, 2.62), respectively, P trend cadmium as a risk factor for breast cancer, especially for both ER+ and HER2- cancer patients.

  11. Regulation of Steroidogenesis, Development, and Cell Differentiation by Steroidogenic Factor-1 and Liver Receptor Homolog-1.

    Science.gov (United States)

    Yazawa, Takashi; Imamichi, Yoshitaka; Miyamoto, Kaoru; Khan, Md Rafiqul Islam; Uwada, Junsuke; Umezawa, Akihiro; Taniguchi, Takanobu

    2015-08-01

    Steroidogenic factor-1 (SF-1) and liver receptor homolog-1 (LRH-1) belong to the nuclear receptor superfamily and are categorized as orphan receptors. In addition to other nuclear receptors, these play roles in various physiological phenomena by regulating the transcription of target genes. Both factors share very similar structures and exhibit common functions. Of these, the roles of SF-1 and LRH-1 in steroidogenesis are the most important, especially that of SF-1, which was originally discovered and named to reflect such roles. SF-1 and LRH-1 are essential for steroid hormone production in gonads and adrenal glands through the regulation of various steroidogenesis-related genes. As SF-1 is also necessary for the development of gonads and adrenal glands, it is also considered a master regulator of steroidogenesis. Recent studies have clearly demonstrated that LRH-1 also represents another master regulator of steroidogenesis, which similarly to SF-1, can induce differentiation of non-steroidogenic stem cells into steroidogenic cells. Here, we review the functions of both factors in these steroidogenesis-related phenomena.

  12. Tumour necrosis factor-alpha impairs neuronal differentiation but not proliferation of hippocampal neural precursor cells: Role of Hes1.

    Science.gov (United States)

    Keohane, Aoife; Ryan, Sinead; Maloney, Eimer; Sullivan, Aideen M; Nolan, Yvonne M

    2010-01-01

    Tumour necrosis factor-alpha (TNFalpha) is a pro-inflammatory cytokine, which influences neuronal survival and function yet there is limited information available on its effects on hippocampal neural precursor cells (NPCs). We show that TNFalpha treatment during proliferation had no effect on the percentage of proliferating cells prepared from embryonic rat hippocampal neurosphere cultures, nor did it affect cell fate towards either an astrocytic or neuronal lineage when cells were then allowed to differentiate. However, when cells were differentiated in the presence of TNFalpha, significantly reduced percentages of newly born and post-mitotic neurons, significantly increased percentages of astrocytes and increased expression of TNFalpha receptors, TNF-R1 and TNF-R2, as well as expression of the anti-neurogenic Hes1 gene, were observed. These data indicate that exposure of hippocampal NPCs to TNFalpha when they are undergoing differentiation but not proliferation has a detrimental effect on their neuronal lineage fate, which may be mediated through increased expression of Hes1.

  13. Characterization of a receptor for human monocyte-derived neutrophil chemotactic factor/interleukin-8

    Energy Technology Data Exchange (ETDEWEB)

    Grob, P.M.; David, E.; Warren, T.C.; DeLeon, R.P.; Farina, P.R.; Homon, C.A. (Boehringer Ingelheim Pharmaceuticals, Inc., Ridgefield, CT (USA))

    1990-05-15

    Monocyte-derived neutrophil chemotactic factor/interleukin-8 (MDNCF/IL-8) is an 8,000-dalton protein produced by monocytes which exhibits activity as a chemoattractant for neutrophils with maximal activity achieved at a concentration of 50 ng/ml. This polypeptide has been iodinated by chloramine-T methodology (350 Ci/mM), and specific receptors for MDNCF/IL-8 have been detected on human neutrophils, U937 cells, THP-1 cells, and dimethyl sulfoxide-differentiated HL-60 cells. The binding of MDNCF/IL-8 to human neutrophils is not inhibited by interleukin-1 alpha, tumor necrosis factor-alpha, insulin, or epidermal growth factor. In addition, chemoattractants such as C5a, fMet-Leu-Phe, leukotriene B4, and platelet-activating factor fail to inhibit binding, suggesting that MDNCF/IL-8 utilizes a unique receptor. The receptor for MDNCF/IL-8 is apparently glycosylated since ligand binding is inhibited by the presence of wheat germ agglutinin, a lectin with a binding specificity for N-acetylglucosamine and neuraminic acid. Steady state binding experiments indicate Kd values of 4 and 0.5 nM and receptor numbers of 75,000 and 7,400 for human neutrophils and differentiated HL-60 cells, respectively. 125I-MDNCF/IL-8 bound to human neutrophils is rapidly internalized and subsequently released from cells as trichloroacetic acid-soluble radioactivity. Affinity labeling experiments suggest that the human neutrophil MDNCF/IL-8 receptor exhibits a mass of approximately 58,000 daltons.

  14. Growth Factor Receptors and Apoptosis Regulators: Signaling Pathways, Prognosis, Chemosensitivity and Treatment Outcomes of Breast Cancer

    Directory of Open Access Journals (Sweden)

    Siddik Sarkar

    2009-01-01

    Full Text Available Biomarkers of breast cancer are necessary for prognosis and prediction to chemotherapy. Prognostic biomarkers provide information regarding outcome irrespective of therapy, while predictive biomarkers provide information regarding response to therapy. Candidate prognostic biomarkers for breast cancers are growth factor receptors, steroid receptors, Ki-67, cyclins, urokinase plasminogen activator, p53, p21, pro- and anti-apoptotic factors, BRCA1 and BRCA2. But currently, the predictive markers are Estrogen and Progesterone receptors responding to endocrine therapy, and HER-2 responding to herceptin. But there are numerous breast cancer cases, where tamoxifen is ineffective even after estrogen receptor positivity. This lead to search of new prognostic and predictive markers and the number of potential markers is constantly increasing due to proteomics and genomics studies. However, most biomarkers individually have poor sensitivity or specificity, or other clinical value. It can be resolved by studying various biomarkers simultaneously, which will help in better prognosis and increasing sensitivity for chemotherapeutic agents. This review is focusing on growth factor receptors, apoptosis markers, signaling cascades, and their correlation with other associated biomarkers in breast cancers. As our knowledge regarding molecular biomarkers for breast cancer increases, prognostic indices will be developed that combine the predictive power of individual molecular biomarkers with specific clinical and pathologic factors. Rigorous comparison of these existing as well as emerging markers with current treatment selection is likely to see an escalation in an era of personalized medicines to ensure the breast cancer patients receive optimal treatment. This will also solve the treatment modalities and complications related to chemotherapeutic regimens.

  15. Mammographic features of calcifications in DCIS: correlation with oestrogen receptor and human epidermal growth factor receptor 2 status

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Min Sun; Moon, Woo Kyung; Chang, Jung Min; Cho, Nariya [Seoul National University College of Medicine, Department of Radiology, Seoul (Korea, Republic of); Park, So Yeon; Won, Jae-Kyung; Jeon, Yoon-Kyung; Park, In Ae [Seoul National University College of Medicine, Department of Pathology, Seoul (Korea, Republic of); Moon, Hyeong-Gon; Han, Wonshik [Seoul National University College of Medicine, Department of Surgery, Seoul (Korea, Republic of)

    2013-08-15

    This study investigated the correlation of oestrogen receptor (ER) and human epidermal growth factor receptor 2 (HER2) status with the probability of malignancy (POM) of mammographic calcifications in ductal carcinoma in situ (DCIS). A total of 101 women (age range, 27-83 years) with pure DCIS that presented as mammographic calcifications were included. Three radiologists independently reviewed mammograms according to the BI-RADS lexicon and provided 100-point POM scores and a BI-RADS category. ER, HER2 and breast cancer subtypes were determined using immunohistochemistry (IHC) and fluorescence in situ hybridisation. Pairwise correlations between POM and IHC biomarker scores were calculated, and mammographic features were compared between breast cancer subtypes. HER2 level positively correlated with the POM score (P < 0.0001) and BI-RADS category (P < 0.0001), and ER level inversely correlated with the POM score (P < 0.013) and BI-RADS category (P < 0.010). Fine linear branching (P = 0.004) and segmental (P = 0.014) calcifications were significantly associated with HER2-positive cancers, and clustered calcifications were more frequently observed in ER-positive cancers (P = 0.014). HER2 status in DCIS correlated positively with the POM of mammographic calcifications, as determined by radiologists on the basis of the BI-RADS lexicon. (orig.)

  16. Structural requirements for inducible shedding of the p55 tumor necrosis factor receptor

    DEFF Research Database (Denmark)

    Brakebusch, C; Varfolomeev, E E; Batkin, M

    1994-01-01

    Induced shedding of the p55 tumor necrosis factor receptor (p55-R) was previously shown to be independent of the amino acid sequence properties of the intracellular domain of this receptor. We now find it also independent of the sequence properties of the transmembrane domain and of the cysteine......-rich region that constitutes most of the extracellular domain of the receptor. The shedding is shown to depend solely on the sequence properties of a small region within the spacer that links the cysteine-rich region in the extracellular domain to the transmembrane domain. Detailed tests of effects......, however, by some mutations that seem to change the conformation of the spacer region. These findings suggest that a short amino acid sequence in the p55-R is essential and sufficient for its shedding and that the shedding is mediated either by a protease with limited sequence specificity or by several...

  17. Oxidative stress effect on progesterone-induced blocking factor (PIBF) binding to PIBF-receptor in lymphocytes.

    Science.gov (United States)

    de la Haba, Carlos; Palacio, José R; Palkovics, Tamas; Szekeres-Barthó, Júlia; Morros, Antoni; Martínez, Paz

    2014-01-01

    Receptor-ligand binding is an essential interaction for biological function. Oxidative stress can modify receptors and/or membrane lipid dynamics, thus altering cell physiological functions. The aim of this study is to analyze how oxidative stress may alter receptor-ligand binding and lipid domain distribution in the case of progesterone-induced blocking factor/progesterone-induced blocking factor-receptor. For membrane fluidity regionalization analysis of MEC-1 lymphocytes, two-photon microscopy was used in individual living cells. Lymphocytes were also double stained with AlexaFluor647/progesterone-induced blocking factor and Laurdan to evaluate -induced blocking factor/progesterone-induced blocking factor-receptor distribution in the different membrane domains, under oxidative stress. A new procedure has been developed which quantitatively analyzes the regionalization of a membrane receptor among the lipid domains of different fluidity in the plasma membrane. We have been able to establish a new tool which detects and evaluates lipid raft clustering from two-photon microscopy images of individual living cells. We show that binding of progesterone-induced blocking factor to progesterone-induced blocking factor-receptor causes a rigidification of plasma membrane which is related to an increase of lipid raft clustering. However, this clustering is inhibited under oxidative stress conditions. In conclusion, oxidative stress decreases membrane fluidity, impairs receptor-ligand binding and reduces lipid raft clustering.

  18. Interleukin-34:A new ligand for Colony-stimulating factor-1Receptor%Interleukin-34: A new ligand for Colony-stimulating factor-1Receptor

    Institute of Scientific and Technical Information of China (English)

    CHEN Yao; Gang-Qing Yao

    2011-01-01

    1 IntroductionColony-stimulating factor-1 ( CSF1 ) is a important hematopoietic growth factor that is involved in the proliferation,differentiation,and survival of monocytes, macrophages, and bone marrow progenitor cells[1].Its receptor (c-Fms) is known as the c-Fmsproto-oncoprotein[2].By far the most definitive studies demonstrating biologic functions for CSF-1 in vivo are those in the op/op mutant mouse.The deficiency results from a single base-pair insertion in the coding region of the gene to product defective CSF-1[3-4].Mice homozygous for this mutation have significant osteopetrosis,low growth rate,low body weight as well as a toothless phenotype because of a severe deficiency of osteoclasts and mononuclear phagocytes[5-6],and are devoid of serum and tissue CSF-1 activity[7].

  19. The Prostaglandin EP3 Receptor Is an Independent Negative Prognostic Factor for Cervical Cancer Patients

    Science.gov (United States)

    Heidegger, Helene; Dietlmeier, Sebastian; Kuhn, Christina; Vattai, Aurelia; Aberl, Caroline; Mahner, Sven; Kost, Bernd

    2017-01-01

    We know that one of the main risk factors for cervical cancer is an infection with high-risk human papillomavirus (HR-HPV). Prostaglandins and their receptors are very important for the tumour growth and tumour-associated angiogenesis. Little is known about the expression of the Prostaglandin E receptor type 3 (EP3) or the Prostaglandin (PG)E2-EP3 signalling in cervical cancer, so the aim of the study was to analyse the expression of the EP3 receptor in cervical cancer and find prognostic factors in relation to survival; EP3 immunohistological staining of 250 cervical cancer slides was performed and analysed with a semi-quantitative score. The statistical evaluation was performed with Statistical Package for the Social Sciences (SPSS) to evaluate the staining results and the survival analyses of the cervical cancer cases. A significant difference was observed in EP3 expression in Fédération Internationale de Gynécologie et d’Obstétrique (FIGO) stadium I versus FIGO stadium II–IV cases. High expression of EP3 (IRS ≥ 1.5) in cervical cancer patients was correlated with poor prognosis in overall survival rates. Survival in adenocarcinoma (AC) of the cervix was lower than in squamous cell carcinoma (SCC). Cox regression analysis shows that EP3 is an independent prognosticator. In this study we could show that the membrane-bound prostaglandin receptor EP3 is an independent prognosticator for cervical cancer patient survival. Targeting the EP3 receptor seems to be an interesting candidate for endocrine therapy. Therefore, more research is needed on the influence of the receptor system and its influence on cervical cancer growth. PMID:28753926

  20. Extrinsic factors regulate partial agonist efficacy of strychnine-sensitive glycine receptors

    Science.gov (United States)

    Farroni, Jeffrey S; McCool, Brian A

    2004-01-01

    the systems examine here, these effects are independent of both absolute expression level and any system-related alterations in the agonist binding site. We conclude that complex interactions between receptor composition and extrinsic factors may play a significant role in determining strychnine-sensitive glycine receptor partial agonist pharmacology. PMID:15301692

  1. Induction of transforming growth factor beta receptors following focal ischemia in the rat brain.

    Directory of Open Access Journals (Sweden)

    Gabriella Pál

    Full Text Available Transforming growth factor-βs (TGF-βs regulate cellular proliferation, differentiation, and survival. TGF-βs bind to type I (TGF-βRI and II receptors (TGF-βRII, which are transmembrane kinase receptors, and an accessory type III receptor (TGF-βRIII. TGF-β may utilize another type I receptor, activin-like kinase receptor (Alk1. TGF-β is neuroprotective in the middle cerebral artery occlusion (MCAO model of stroke. Recently, we reported the expression pattern of TGF-β1-3 after MCAO. To establish how TGF-βs exert their actions following MCAO, the present study describes the induction of TGF-βRI, RII, RIII and Alk1 at 24 h, 72 h and 1 mo after transient 1 h MCAO as well as following 24 h permanent MCAO using in situ hybridization histochemistry. In intact brain, only TGF-βRI had significant expression: neurons in cortical layer IV contained TGF-βRI. At 24 h after the occlusion, no TGF-β receptors showed induction. At 72 h following MCAO, all four types of TGF-β receptors were induced in the infarct area, while TGF-βRI and RII also appeared in the penumbra. Most cells with elevated TGF-βRI mRNA levels were microglia. TGF-βRII co-localized with both microglial and endothelial markers while TGF-βRIII and Alk1 were present predominantly in endothels. All four TGF-β receptors were induced within the lesion 1 mo after the occlusion. In particular, TGF-βRIII was further induced as compared to 72 h after MCAO. At this time point, TGF-βRIII signal was predominantly not associated with blood vessels suggesting its microglial location. These data suggest that TGF-β receptors are induced after MCAO in a timely and spatially regulated fashion. TGF-β receptor expression is preceded by increased TGF-β expression. TGF-βRI and RII are likely to be co-expressed in microglial cells while Alk1, TGF-βRII, and RIII in endothels within the infarct where TGF-β1 may be their ligand. At later time points, TGF-βRIII may also appear in glial cells

  2. RANKL employs distinct binding modes to engage RANK and the osteoprotegerin decoy receptor.

    Science.gov (United States)

    Nelson, Christopher A; Warren, Julia T; Wang, Michael W-H; Teitelbaum, Steven L; Fremont, Daved H

    2012-11-07

    Osteoprotegerin (OPG) and receptor activator of nuclear factor κB (RANK) are members of the tumor necrosis factor receptor (TNFR) superfamily that regulate osteoclast formation and function by competing for RANK ligand (RANKL). RANKL promotes osteoclast development through RANK activation, while OPG inhibits this process by sequestering RANKL. For comparison, we solved crystal structures of RANKL with RANK and RANKL with OPG. Complementary biochemical and functional studies reveal that the monomeric cytokine-binding region of OPG binds RANKL with ∼500-fold higher affinity than RANK and inhibits RANKL-stimulated osteoclastogenesis ∼150 times more effectively, in part because the binding cleft of RANKL makes unique contacts with OPG. Several side chains as well as the C-D and D-E loops of RANKL occupy different orientations when bound to OPG versus RANK. High affinity OPG binding requires a 90s loop Phe residue that is mutated in juvenile Paget's disease. These results suggest cytokine plasticity may help to fine-tune specific tumor necrosis factor (TNF)-family cytokine/receptor pair selectivity.

  3. Altered Fibroblast Growth Factor Receptor 4 Stability Promotes Prostate Cancer Progression

    Directory of Open Access Journals (Sweden)

    Jianghua Wang

    2008-08-01

    Full Text Available Fibroblast growth factor receptor 4 (FGFR-4 is expressed at significant levels in almost all human prostate cancers, and expression of its ligands is ubiquitous. A common polymorphism of FGFR-4 in which arginine (Arg388 replaces glycine (Gly388 at amino acid 388 is associated with progression in human prostate cancer. We show that the FGFR-4 Arg388 polymorphism, which is present in most prostate cancer patients, results in increased receptor stability and sustained receptor activation. In patients bearing the FGFR-4 Gly388 variant, expression of Huntingtin-interacting protein 1 (HIP1, which occurs in more than half of human prostate cancers, also results in FGFR-4 stabilization. This is associated with enhanced proliferation and anchorage-independent growth in vitro. Our findings indicate that increased receptor stability and sustained FGFR-4 signaling occur in most human prostate cancers due to either the presence of a common genetic polymorphism or the expression of a protein that stabilizes FGFR-4. Both of these alterations are associated with clinical progression in patients with prostate cancer. Thus, FGFR-4 signaling and receptor turnover are important potential therapeutic targets in prostate cancer.

  4. Epidermal growth factor receptors destined for the nucleus are internalized via a clathrin-dependent pathway

    Energy Technology Data Exchange (ETDEWEB)

    De Angelis Campos, Ana Carolina; Rodrigues, Michele Angela; Andrade, Carolina de; Miranda de Goes, Alfredo [Department of Biochemistry and Immunology, Federal University of Minas Gerais, Belo Horizonte, MG (Brazil); Nathanson, Michael H. [Department of Internal Medicine, Yale University School of Medicine, New Haven, CT (United States); Gomes, Dawidson A., E-mail: dawidson@icb.ufmg.br [Department of Biochemistry and Immunology, Federal University of Minas Gerais, Belo Horizonte, MG (Brazil)

    2011-08-26

    Highlights: {yields} EGF and its receptor translocates to the nucleus in liver cells. {yields} Real time imaging shows that EGF moves to the nucleus. {yields} EGF moves with its receptor to the nucleus. {yields} Dynamin and clathrin are necessary for EGFR nuclear translocation. -- Abstract: The epidermal growth factor (EGF) transduces its actions via the EGF receptor (EGFR), which can traffic from the plasma membrane to either the cytoplasm or the nucleus. However, the mechanism by which EGFR reaches the nucleus is unclear. To investigate these questions, liver cells were analyzed by immunoblot of cell fractions, confocal immunofluorescence and real time confocal imaging. Cell fractionation studies showed that EGFR was detectable in the nucleus after EGF stimulation with a peak in nuclear receptor after 10 min. Movement of EGFR to the nucleus was confirmed by confocal immunofluorescence and labeled EGF moved with the receptor to the nucleus. Small interference RNA (siRNA) was used to knockdown clathrin in order to assess the first endocytic steps of EGFR nuclear translocation in liver cells. A mutant dynamin (dynamin K44A) was also used to determine the pathways for this traffic. Movement of labeled EGF or EGFR to the nucleus depended upon dynamin and clathrin. This identifies the pathway that mediates the first steps for EGFR nuclear translocation in liver cells.

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

    Institute of Scientific and Technical Information of China (English)

    MinZHANG; XinZHANG; Chun-xueBAI; JieCHEN; MinQWEI

    2004-01-01

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

  6. Cannabinoid receptor-2 selective antagonist negatively regulates receptor activator of nuclear factor kappa B ligand mediated osteoclastogenesis

    Institute of Scientific and Technical Information of China (English)

    GENG De-chun; XU Yao-zeng; YANG Hui-lin; ZHU Guang-ming; WANG Xian-bin; ZHU Xue-song

    2011-01-01

    Background The cannabinoid receptor-2 (CB2) is important for bone remodeling. In this study, we investigated the effects of CB2 selective antagonist (AM630) on receptor activator of nuclear factor kappa B (RANK) ligand (RANKL)induced osteoclast differentiation and the underlying signaling pathway using a monocyte-macrophage cell line-RAW264.7.Methods RAW264.7 was cultured with RANKL for 6 days and then treated with AM630 for 24 hours. Mature osteoclasts were measured by tartrate-resistant acid phosphatase (TRAP) staining using a commercial kit. Total ribonucleic acid (RNA)was isolated and real-time reverse transcriptase-polymerase chain reaction (RT-PCR) was done to examine the expression of RANK, cathepsin K (CPK) and nuclear factor kappa B (NF-κB). The extracellular signal-regulated kinase (ERK),phosphorylation of ERK (P-ERK) and NF-κB production were tested by Western blotting. The effect of AM630 on RAW264.7 viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) assay.Results AM630 did not affect the viability of RAW264.7. However, this CB2 selective antagonist markedly inhibited osteoclast formation and the inhibition rate was dose-dependent. The dose of >100 nmol/L could reduce TRAP positive cells to the levels that were significantly lower than the control. AM630 suppressed the expression of genes associated with osteoclast differentiation and activation, such as RANK and CPK. An analysis of a signaling pathway showed that AM630 inhibited the RANKL-induced activation of ERK, but not NF-κB.Conclusion AM630 could inhibit the osteoclastogenesis from RAW264.7 induced with RANKL.

  7. Combinatorial activation and repression by seven transcription factors specify Drosophila odorant receptor expression.

    Directory of Open Access Journals (Sweden)

    Shadi Jafari

    Full Text Available The mechanism that specifies olfactory sensory neurons to express only one odorant receptor (OR from a large repertoire is critical for odor discrimination but poorly understood. Here, we describe the first comprehensive analysis of OR expression regulation in Drosophila. A systematic, RNAi-mediated knock down of most of the predicted transcription factors identified an essential function of acj6, E93, Fer1, onecut, sim, xbp1, and zf30c in the regulation of more than 30 ORs. These regulatory factors are differentially expressed in antennal sensory neuron classes and specifically required for the adult expression of ORs. A systematic analysis reveals not only that combinations of these seven factors are necessary for receptor gene expression but also a prominent role for transcriptional repression in preventing ectopic receptor expression. Such regulation is supported by bioinformatics and OR promoter analyses, which uncovered a common promoter structure with distal repressive and proximal activating regions. Thus, our data provide insight into how combinatorial activation and repression can allow a small number of transcription factors to specify a large repertoire of neuron classes in the olfactory system.

  8. Soluble TNF-Alpha-Receptors I Are Prognostic Markers in TIPS-Treated Patients with Cirrhosis and Portal Hypertension

    DEFF Research Database (Denmark)

    Trebicka, Jonel; Krag, Aleksander; Gansweid, Stefan

    2013-01-01

    TNFα levels are increased in liver cirrhosis even in the absence of infection, most likely owing to a continuous endotoxin influx into the portal blood. Soluble TNFα receptors (sTNFR type I and II) reflect release of the short-lived TNFα, because they are cleaved from the cells after binding...

  9. Transforming growth factor β receptor type 1 is essential for female reproductive tract integrity and function.

    Directory of Open Access Journals (Sweden)

    Qinglei Li

    2011-10-01

    Full Text Available The transforming growth factor β (TGFβ superfamily proteins are principle regulators of numerous biological functions. Although recent studies have gained tremendous insights into this growth factor family in female reproduction, the functions of the receptors in vivo remain poorly defined. TGFβ type 1 receptor (TGFBR1, also known as activin receptor-like kinase 5, is the major type 1 receptor for TGFβ ligands. Tgfbr1 null mice die embryonically, precluding functional characterization of TGFBR1 postnatally. To study TGFBR1-mediated signaling in female reproduction, we generated a mouse model with conditional knockout (cKO of Tgfbr1 in the female reproductive tract using anti-Müllerian hormone receptor type 2 promoter-driven Cre recombinase. We found that Tgfbr1 cKO females are sterile. However, unlike its role in growth differentiation factor 9 (GDF9 signaling in vitro, TGFBR1 seems to be dispensable for GDF9 signaling in vivo. Strikingly, we discovered that the Tgfbr1 cKO females develop oviductal diverticula, which impair embryo development and transit of embryos to the uterus. Molecular analysis further demonstrated the dysregulation of several cell differentiation and migration genes (e.g., Krt12, Ace2, and MyoR that are potentially associated with female reproductive tract development. Moreover, defective smooth muscle development was also revealed in the uteri of the Tgfbr1 cKO mice. Thus, TGFBR1 is required for female reproductive tract integrity and function, and disruption of TGFBR1-mediated signaling leads to catastrophic structural and functional consequences in the oviduct and uterus.

  10. Transforming Growth Factor β Receptor Type 1 Is Essential for Female Reproductive Tract Integrity and Function

    Science.gov (United States)

    Li, Qinglei; Agno, Julio E.; Edson, Mark A.; Nagaraja, Ankur K.; Nagashima, Takashi; Matzuk, Martin M.

    2011-01-01

    The transforming growth factor β (TGFβ) superfamily proteins are principle regulators of numerous biological functions. Although recent studies have gained tremendous insights into this growth factor family in female reproduction, the functions of the receptors in vivo remain poorly defined. TGFβ type 1 receptor (TGFBR1), also known as activin receptor-like kinase 5, is the major type 1 receptor for TGFβ ligands. Tgfbr1 null mice die embryonically, precluding functional characterization of TGFBR1 postnatally. To study TGFBR1–mediated signaling in female reproduction, we generated a mouse model with conditional knockout (cKO) of Tgfbr1 in the female reproductive tract using anti-Müllerian hormone receptor type 2 promoter-driven Cre recombinase. We found that Tgfbr1 cKO females are sterile. However, unlike its role in growth differentiation factor 9 (GDF9) signaling in vitro, TGFBR1 seems to be dispensable for GDF9 signaling in vivo. Strikingly, we discovered that the Tgfbr1 cKO females develop oviductal diverticula, which impair embryo development and transit of embryos to the uterus. Molecular analysis further demonstrated the dysregulation of several cell differentiation and migration genes (e.g., Krt12, Ace2, and MyoR) that are potentially associated with female reproductive tract development. Moreover, defective smooth muscle development was also revealed in the uteri of the Tgfbr1 cKO mice. Thus, TGFBR1 is required for female reproductive tract integrity and function, and disruption of TGFBR1–mediated signaling leads to catastrophic structural and functional consequences in the oviduct and uterus. PMID:22028666

  11. Fibroblast Growth Factor 10-Fibroblast Growth Factor Receptor 2b Mediated Signaling Is Not Required for Adult Glandular Stomach Homeostasis

    Science.gov (United States)

    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

  12. Fibroblast growth factor 10-fibroblast growth factor receptor 2b mediated signaling is not required for adult glandular stomach homeostasis.

    Directory of Open Access Journals (Sweden)

    Allison L Speer

    Full Text Available 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.

  13. Fibroblast growth factor 10-fibroblast growth factor receptor 2b mediated signaling is not required for adult glandular stomach homeostasis.

    Science.gov (United States)

    Speer, Allison L; Al Alam, Denise; 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.

  14. A novel fibroblast growth factor receptor family member promotes neuronal outgrowth and synaptic plasticity in aplysia.

    Science.gov (United States)

    Pollak, Daniela D; Minh, Bui Quang; Cicvaric, Ana; Monje, Francisco J

    2014-11-01

    Fibroblast Growth Factor (FGF) Receptors (FGFRs) regulate essential biological processes, including embryogenesis, angiogenesis, cellular growth and memory-related long-term synaptic plasticity. Whereas canonical FGFRs depend exclusively on extracellular Immunoglobulin (Ig)-like domains for ligand binding, other receptor types, including members of the tropomyosin-receptor-kinase (Trk) family, use either Ig-like or Leucine-Rich Repeat (LRR) motifs, or both. Little is known, however, about the evolutionary events leading to the differential incorporation of LRR domains into Ig-containing tyrosine kinase receptors. Moreover, although FGFRs have been identified in many vertebrate species, few reports describe their existence in invertebrates. Information about the biological relevance of invertebrate FGFRs and evolutionary divergences between them and their vertebrate counterparts is therefore limited. Here, we characterized ApLRRTK, a neuronal cell-surface protein recently identified in Aplysia. We unveiled ApLRRTK as the first member of the FGFRs family deprived of Ig-like domains that instead contains extracellular LRR domains. We describe that ApLRRTK exhibits properties typical of canonical vertebrate FGFRs, including promotion of FGF activity, enhancement of neuritic outgrowth and signaling via MAPK and the transcription factor CREB. ApLRRTK also enhanced the synaptic efficiency of neurons known to mediate in vivo memory-related defensive behaviors. These data reveal a novel molecular regulator of neuronal function in invertebrates, provide the first evolutionary linkage between LRR proteins and FGFRs and unveil an unprecedented mechanism of FGFR gene diversification in primeval central nervous systems.

  15. Type I insulin-like growth factor receptor signaling in skeletal muscle regeneration and hypertrophy.

    Science.gov (United States)

    Philippou, A; Halapas, A; Maridaki, M; Koutsilieris, M

    2007-01-01

    Skeletal muscle is able not only to increase its mass as an adaptation to mechanical loading generated by and imposed upon muscle but also to regenerate after damage, via its intrinsic regulation of gene transcription. Both cellular processes, muscle regeneration and hypertrophy, are mediated by the activation, proliferation and differentiation of muscle satellite cells and appear to be modulated by the mitotic and myogenic activity of locally produced insulin-like growth factor 1 (IGF-1), which functions in an autocrine/paracrine mode. Differentiation of satellite cells into myoblasts involves the regulation of skeletal muscle-specific proteins belonging to the family of myogenic regulatory factors (MRFs). The endocrine, autocrine and paracrine functions of IGF-1 are mediated through binding to the type I IGF receptor (IGF-1.R), which is a ligand-activated receptor tyrosine kinase. The binding of IGF-1 to IGF-1.R induces its autophosphorylation, which recruits specific cytoplasmic molecules containing the Insulin Receptor Substrate Proteins (IRS). The recruitment of IRS proteins by IGF-1/IGF-1.R binding is a critical level at which the proliferative and differentiative actions of IGF-1 diverge. Specific signaling pathways downstream of IGF-1, potentially involved in the mitogenic and myogenic responses and mediating skeletal muscle protein synthesis and hypertrophy following exercise-induced muscle overloading and damage, are discussed. A potential alternative activation of different signaling pathway(s) via a different receptor remains to be demonstrated.

  16. A Murine Fibroblast Growth Factor (FGF) Receptor Expressed in CHO Cells is Activated by Basic FGF and Kaposi FGF

    Science.gov (United States)

    Mansukhani, Alka; Moscatelli, David; Talarico, Daniela; Levytska, Vera; Basilico, Claudio

    1990-06-01

    We have cloned a murine cDNA encoding a tyrosine kinase receptor with about 90% similarity to the chicken fibroblast growth factor (FGF) receptor and the human fms-like gene (FLG) tyrosine kinase. This mouse receptor lacks 88 amino acids in the extracellular portion, leaving only two immunoglobulin-like domains compared to three in the chicken FGF receptor. The cDNA was cloned into an expression vector and transfected into receptor-negative CHO cells. We show that cells expressing the receptor can bind both basic FGF and Kaposi FGF. Although the receptor binds basic FGF with a 15- to 20-fold higher affinity, Kaposi FGF is able to induce down-regulation of the receptor to the same extent as basic FGF. The receptor is phosphorylated upon stimulation with both FGFs, DNA synthesis is stimulated, and a proliferative response is produced in cells expressing the receptor, whereas cells expressing the cDNA in the antisense orientation show none of these responses to basic FGF or Kaposi FGF. Thus this receptor can functionally interact with two growth factors of the FGF family.

  17. Nanoconjugation prolongs endosomal signaling of the epidermal growth factor receptor and enhances apoptosis

    Science.gov (United States)

    Wu, L.; Xu, F.; Reinhard, B. M.

    2016-07-01

    It is becoming increasingly clear that intracellular signaling can be subject to strict spatial control. As the covalent attachment of a signaling ligand to a nanoparticle (NP) impacts ligand-receptor binding, uptake, and trafficking, nanoconjugation provides new opportunities for manipulating intracellular signaling in a controlled fashion. To establish the effect of nanoconjugation on epidermal growth factor (EGF) mediated signaling, we investigate here the intracellular fate of nanoconjugated EGF (NP-EGF) and its bound receptor (EGFR) by quantitative correlated darkfield/fluorescence microscopy and density-based endosomal fractionation. We demonstrate that nanoconjugation prolongs the dwell time of phosphorylated receptors in the early endosomes and that the retention of activated EGFR in the early endosomes is accompanied by an EGF mediated apoptosis at effective concentrations that do not induce apoptosis in the case of free EGF. Overall, these findings indicate nanoconjugation as a rational strategy for modifying signaling that acts by modulating the temporo-spatial distribution of the activated EGF-EGFR ligand-receptor complex.It is becoming increasingly clear that intracellular signaling can be subject to strict spatial control. As the covalent attachment of a signaling ligand to a nanoparticle (NP) impacts ligand-receptor binding, uptake, and trafficking, nanoconjugation provides new opportunities for manipulating intracellular signaling in a controlled fashion. To establish the effect of nanoconjugation on epidermal growth factor (EGF) mediated signaling, we investigate here the intracellular fate of nanoconjugated EGF (NP-EGF) and its bound receptor (EGFR) by quantitative correlated darkfield/fluorescence microscopy and density-based endosomal fractionation. We demonstrate that nanoconjugation prolongs the dwell time of phosphorylated receptors in the early endosomes and that the retention of activated EGFR in the early endosomes is accompanied by an EGF

  18. Antioxidants for Healthy Skin: The Emerging Role of Aryl Hydrocarbon Receptors and Nuclear Factor-Erythroid 2-Related Factor-2.

    Science.gov (United States)

    Furue, Masutaka; Uchi, Hiroshi; Mitoma, Chikage; Hashimoto-Hachiya, Akiko; Chiba, Takahito; Ito, Takamichi; Nakahara, Takeshi; Tsuji, Gaku

    2017-03-03

    Skin is the outermost part of the body and is, thus, inevitably exposed to UV rays and environmental pollutants. Oxidative stress by these hazardous factors accelerates skin aging and induces skin inflammation and carcinogenesis. Aryl hydrocarbon receptors (AHRs) are chemical sensors that are abundantly expressed in epidermal keratinocytes and mediate the production of reactive oxygen species. To neutralize or minimize oxidative stress, the keratinocytes also express nuclear factor-erythroid 2-related factor-2 (NRF2), which is a master switch for antioxidant signaling. Notably, there is fine-tuned crosstalk between AHR and NRF2, which mutually increase or decrease their activation states. Many NRF2-mediated antioxidant phytochemicals are capable of up- and downmodulating AHR signaling. The precise mechanisms by which these phytochemicals differentially affect the AHR and NRF2 system remain largely unknown and warrant future investigation.

  19. Antioxidants for Healthy Skin: The Emerging Role of Aryl Hydrocarbon Receptors and Nuclear Factor-Erythroid 2-Related Factor-2

    Science.gov (United States)

    Furue, Masutaka; Uchi, Hiroshi; Mitoma, Chikage; Hashimoto-Hachiya, Akiko; Chiba, Takahito; Ito, Takamichi; Nakahara, Takeshi; Tsuji, Gaku

    2017-01-01

    Skin is the outermost part of the body and is, thus, inevitably exposed to UV rays and environmental pollutants. Oxidative stress by these hazardous factors accelerates skin aging and induces skin inflammation and carcinogenesis. Aryl hydrocarbon receptors (AHRs) are chemical sensors that are abundantly expressed in epidermal keratinocytes and mediate the production of reactive oxygen species. To neutralize or minimize oxidative stress, the keratinocytes also express nuclear factor-erythroid 2-related factor-2 (NRF2), which is a master switch for antioxidant signaling. Notably, there is fine-tuned crosstalk between AHR and NRF2, which mutually increase or decrease their activation states. Many NRF2-mediated antioxidant phytochemicals are capable of up- and downmodulating AHR signaling. The precise mechanisms by which these phytochemicals differentially affect the AHR and NRF2 system remain largely unknown and warrant future investigation. PMID:28273792

  20. A Structural Investigation into Oct4 Regulation by Orphan Nuclear Receptors, Germ Cell Nuclear Factor (GCNF) and Liver Receptor Homolog-1 (LRH-1).

    Science.gov (United States)

    Weikum, Emily R; Tuntland, Micheal L; Murphy, Michael N; Ortlund, Eric A

    2016-10-27

    Oct4 is a transcription factor required for maintaining pluripotency and self-renewal in stem cells. Prior to differentiation, Oct4 must be silenced to allow for the development of the three germ layers in the developing embryo. This fine-tuning is controlled by the nuclear receptors, liver receptor homolog-1 and germ cell nuclear factor. Liver receptor homolog-1 is responsible for driving the expression of Oct4 where germ cell nuclear factor represses its expression upon differentiation. Both receptors bind to a DR0 motif located within the Oct4 promoter. Here, we present the first structure of mouse germ cell nuclear factor DNA binding domain in complex with the Oct4 DR0. The overall structure revealed two molecules bound in a head-to-tail fashion on opposite sides of the DNA. Additionally, we solved the structure of the human liver receptor homolog-1 DNA binding domain bound to the same element. We explore the structural elements that govern Oct4 recognition by these two nuclear receptors.

  1. Mutations in fibroblast growth factor receptors: Phenotypic consequences during eukaryotic development

    Energy Technology Data Exchange (ETDEWEB)

    Park, W.J.; Bellus, G.A.; Jabs, E.W. [Johns Hopkins Univ. School of Medicine, Baltimore, MD (United States)

    1995-10-01

    Recently, a tremendous amount of excitement and interest has been generated by the rapid succession of discoveries in the human fibroblast growth factor receptor (FGFR) field. In less than a year, mutations in three FGFRs (FGFR1-FGFR3) have been associated with three skeletal dysplasias and four craniosynostotic syndromes. FGFRs are members of the receptor tyrosine kinase family that bind fibroblast growth factors (FGFs). The FGF family consists of structurally related polypeptides that play a key role in numerous aspects of embryogenesis, growth, and homeostasis. FGFs have a potent growth stimulatory and/or differentiation-inducing effect on cells such as those derived from the early-embryonic mesoderm or ectoderm. In addition to mitogenesis and differentiation, FGFs also stimulate chemotaxis, cell survival, and angiogenesis. FGFs mediate cellular responses on binding to and activation of FGFRs. 45 refs., 2 figs., 1 tab.

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

    Science.gov (United States)

    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.

  3. Nonsmall Cell Lung Cancer Therapy: Insight into Multitargeted Small-Molecule Growth Factor Receptor Inhibitors

    Directory of Open Access Journals (Sweden)

    Mridul Roy

    2013-01-01

    Full Text Available To date, lung cancer is the leading cause of cancer-related death worldwide, among which nonsmall cell lung cancer (NSCLC comprises about 85%. Taking into account the side effects of surgery, radiation, platinum-based doublet chemotherapy, and the growth self-sufficiency characteristic of cancer cells, drugs have been discovered toward growth factor receptor (GFR to treat NSCLC. As expected, these drugs provide a greater benefit. To increase the efficacy of such growth factor receptor tyrosine kinase inhibitors (RTKIs, coinhibition of GFR signaling pathways and combination of inhibitors along with radiation or chemotherapy have drew intense insight. Although clinical trials about single-agent RTKIs or their combination strategies suggest their increase potency against cancer, they are not beyond adverse effects, and sometimes the effects are more deadly than chemotherapy. Nevertheless the hope for RTKIs may be proved true by further researches and digging deep into cancer therapeutics.

  4. Mactosylceramide Prevents Glial Cell Overgrowth by Inhibiting Insulin and Fibroblast Growth Factor Receptor Signaling

    DEFF Research Database (Denmark)

    Gerdøe-Kristensen, Stine; Lund, Viktor K; Wandall, Hans H

    2017-01-01

    , in which the mannosyltransferase Egghead controls conversion of glucosylceramide (GlcCer) to mactosylceramide (MacCer). Lack of elongated GSL in egghead (egh) mutants causes overgrowth of subperineurial glia (SPG), largely due to aberrant activation of phosphatidylinositol 3-kinase (PI3K). However, to what...... extent this effect involves changes in upstream signaling events is unresolved. We show here that glial overgrowth in egh is strongly linked to increased activation of Insulin and Fibroblast Growth Factor receptors (FGFR). Glial hypertrophy is phenocopied when overexpressing gain-of-function mutants...... hyperactivation is caused by absence of MacCer and not by GlcCer accumulation. We conclude that an early product in GSL biosynthesis, MacCer, prevents inappropriate activation of Insulin and Fibroblast Growth Factor Receptors in Drosophila glia. This article is protected by copyright. All rights reserved....

  5. Cognitive disorder and changes in cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor following brain injury

    Institute of Scientific and Technical Information of China (English)

    Weiliang Zhao; Dezhi Kang; Yuanxiang Lin

    2008-01-01

    BACKGROUND: Learning and memory damage is one of the most permanent and the severest symptoms of traumatic brain injury; it can seriously influence the normal life and work of patients. Some research has demonstrated that cognitive disorder is closely related to nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor. OBJECTIVE: To summarize the cognitive disorder and changes in nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor following brain injury. RETRIEVAL STRATEGY: A computer-based online search was conducted in PUBMED for English language publications containing the key words "brain injured, cognitive handicap, acetylcholine, N-methyl-D aspartate receptors, neural cell adhesion molecule, brain-derived neurotrophic factor" from January 2000 to December 2007. There were 44 papers in total. Inclusion criteria: ① articles about changes in nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor following brain injury; ② articles in the same researching circle published in authoritative journals or recently published. Exclusion criteria: duplicated articles.LITERATURE EVALUATION: References were mainly derived from research on changes in these four factors following brain injury. The 20 included papers were clinical or basic experimental studies. DATA SYNTHESIS: After craniocerebral injury, changes in these four factors in brain were similar to those during recovery from cognitive disorder, to a certain degree. Some data have indicated that activation of nicotine cholinergic receptors, N-methyl-D aspartate receptors, neural cell adhesion molecule, and brain-derived neurotrophic factor could greatly improve cognitive disorder following brain injury. However, there are still a lot of questions remaining; for example, how do these

  6. Rationale for targeting fibroblast growth factor receptor signaling in breast cancer

    OpenAIRE

    André, Fabrice; Cortés, Javier

    2015-01-01

    Fibroblast growth factor receptor (FGFR) signaling is involved in multiple biological processes, including cell proliferation, survival, differentiation, migration, and apoptosis during embryonic development and adult tissue homeostasis. Given its role in the activation of critical signaling pathways, aberrant FGFR signaling has been implicated in multiple cancer types. A comprehensive search of PubMed and congress abstracts was conducted to identify reports on FGFR pathway components in brea...

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

    Directory of Open Access Journals (Sweden)

    Zhong SHI

    2015-02-01

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

  8. Cutaneous adverse events of epidermal growth factor receptor inhibitors: A retrospective review of 99 cases

    Directory of Open Access Journals (Sweden)

    Kumutnart Chanprapaph

    2015-01-01

    Full Text Available Background: Previous reports regarding the cutaneous adverse events of epidermal growth factor receptor inhibitors are mostly limited to small case reports and case series, mainly involving Caucasian patients. Aims: We describe the trends in the clinical presentation of Asian patients who had cutaneous adverse events induced by epidermal growth factor receptor inhibitors and to explore the relationship between skin adverse events and tumor response. Methods: From 2006 to 2010, medical records of Thai patients with non-small cell lung cancer receiving epidermal growth factor receptor inhibitors were retrieved and analyzed. Results: In all, 99 patients were reviewed and analyzed. Erlotinib and gefitinib were commenced in 75 (75.8% and 24 (24.2% patients, respectively. Cutaneous adverse events occurred in 43 (57.3% patients receiving erlotinib and in 15 (62.5% patients receiving gefitinib. The most common adverse event was xerosis (52.5%. Less common adverse events included papulo-pustular eruption (27.3%, erythematous maculopapular rash (11.1%, mucositis (6.7%, paronychia (5.1%, and trichomegaly (2%. Elderly patients had a higher occurrence of xerosis. The presence of cutaneous adverse events was significantly higher in subjects who had a tumor response. Limitations: The limitations of study include its retrospective nature, and the initial screening of cutaneous adverse events was done by non-dermatologists. Conclusions: Cutaneous adverse events due to epidermal growth factor receptor inhibitors are not uncommon in the Asian population. We found a positive correlation between the occurrences of cutaneou adverse events and tumor response supporting the view that they are surrogate markers for therapeutic response.

  9. Novel Mutations and Deletions of the KIT (Steel Factor Receptor) Gene in Human Piebaldism

    OpenAIRE

    Ezoe, Kazuhiko; Holmes, Stuart A.; Ho, Lingling; Bennett, Christopher P.; Bolognia, Jean L.; Brueton, Louise; Burn, John; Falabella, Rafael; Gatto, Emilia M.; Ishii, Norihisa; Moss, Celia; Pittelkow, Mark R.; Thompson, Elizabeth; Ward, K. Anne; Spritz, Richard A.

    1995-01-01

    Piebaldism is an autosomal dominant genetic disorder of pigmentation characterized by white patches of skin and hair. Melanocytes are lacking in these hypopigmented regions, the result of mutations of the KIT gene, which encodes the cell surface receptor for steel factor (SLF). We describe the analysis of 26 unrelated patients with piebaldism-like hypopigmentation—17 typical patients, 5 with atypical clinical features or family histories, and 4 with other disorders that involve white spotting...

  10. Glucocorticoid-induced tumour necrosis factor receptor (GITR) and its ligand (GITRL) in atopic dermatitis

    DEFF Research Database (Denmark)

    Baumgartner-Nielsen, Jane; Vestergaard, Christian; Thestrup-Pedersen, K.

    2006-01-01

    The glucocorticoid-induced tumour necrosis factor receptor-related gene (GITR) is expressed on regulatory T-cells (Treg), which are CD4+CD25+ lymphocytes. Binding of the GITR-ligand (GITRL) leads to downregulation of the regulatory function of Tregs. Patients suffering from a defect in their Treg......-cells are localized in the vicinity of GITRL-expressing cells in atopic dermatitis skin, the GITR/GITRL interaction may serve to perpetuate the inflammation locally....

  11. Design and characteristics of cytotoxic fibroblast growth factor 1 conjugate for fibroblast growth factor receptor-targeted cancer therapy

    Directory of Open Access Journals (Sweden)

    Szlachcic A

    2016-08-01

    Full Text Available Anna Szlachcic, Malgorzata Zakrzewska, Michal Lobocki, Piotr Jakimowicz, Jacek Otlewski Department of Protein Engineering, Faculty of Biotechnology, University of Wroclaw, Wroclaw, Poland Abstract: Fibroblast growth factor receptors (FGFRs are attractive candidate cancer therapy targets as they are overexpressed in multiple types of tumors, such as breast, prostate, bladder, and lung cancer. In this study, a natural ligand of FGFR, an engineered variant of fibroblast growth factor 1 (FGF1V, was conjugated to a potent cytotoxic drug, monomethyl auristatin E (MMAE, and used as a targeting agent for cancer cells overexpressing FGFRs, similar to antibodies in antibody–drug conjugates. The FGF1V–valine–citrulline–MMAE conjugate showed a favorable stability profile, bound FGFRs on the cell surface specifically, and efficiently released the drug (MMAE upon cleavage by the lysosomal protease cathepsin B. Importantly, the conjugate showed a prominent cytotoxic effect toward cell lines expressing FGFR. FGF1V–vcMMAE was highly cytotoxic at concentrations even an order of magnitude lower than those found for free MMAE. This effect was FGFR-specific as cells lacking FGFR did not show any increased mortality. Keywords: fibroblast growth factor 1, FGF receptor, targeted cancer therapy, cytotoxic conjugates, FGFR-dependent cancer, MMAE, auristatin

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

    Science.gov (United States)

    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-α (TGF-α) 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-α antibodies. Some selected HCC cases were submitted for FISH technique to detect EGFR gene alteration. By immunohistochemistry EGFR and TGF-α 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-α 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.

  13. The role of tumour necrosis factor alpha and soluble tumour necrosis factor alpha receptors in the symptomatology of schizophrenia.

    Science.gov (United States)

    Turhan, Levent; Batmaz, Sedat; Kocbiyik, Sibel; Soygur, Arif Haldun

    2016-07-01

    Background Immunological mechanisms may be responsible for the development and maintenance of schizophrenia symptoms. Aim The aim of this study is to measure tumour necrosis factor-alpha (TNF-α), soluble tumour necrosis factor-alpha receptor I (sTNF-αRI), and soluble tumour necrosis factor-alpha receptor II (sTNF-αRII) levels in patients with schizophrenia and healthy individuals, and to determine their relationship with the symptoms of schizophrenia. Methods Serum TNF-α, sTNF-αRI and sTNF-αRII levels were measured. The Positive and Negative Syndrome Scale (PANSS) was administered for patients with schizophrenia (n = 35), and the results were compared with healthy controls (n = 30). Hierarchical regression analyses were undertaken to predict the levels of TNF-α, sTNF-αRI and sTNF-αRII. Results No significant difference was observed in TNF-α levels, but sTNF-αRI and sTNF-αRII levels were lower in patients with schizophrenia. Serum sTNF-αRI and sTNF-αRII levels were found to be negatively correlated with the negative subscale score of the PANSS, and sTNF-αRI levels were also negatively correlated with the total score of the PANSS. Smoking, gender, body mass index were not correlated with TNF-α and sTNF-α receptor levels. Conclusions These results suggest that there may be a change in anti-inflammatory response in patients with schizophrenia due to sTNF-αRI and sTNF-αRII levels. The study also supports low levels of TNF activity in schizophrenia patients with negative symptoms.

  14. Tyrosine Kinase Domain Gene Polymorphism of Epidermal Growth Factor Receptor in Gastric Cancer in Northern Iran

    Directory of Open Access Journals (Sweden)

    Jeivad F

    2012-01-01

    Full Text Available Background: Gastric cancer is one of the most common diseases of digestive system with a low 5-year survival rate and metastasis is the main cause of death. Multi-factors, such as changes in molecular pathways and deregulation of cells are involved in the disease development. Epidermal growth factor receptor pathway (EGFR which is associated with cell proliferation and survival can influence cancer development. EGFR function is governed by its genetic polymorphism; thus, we aimed to study the tyrosine kinase domain gene mutations of the receptor in patients with gastric cancer.Methods : In this experimental study, 123 subjects (83 patients with gastric cancer and 40 normal subjects were investigated in north of Iran for EGFR gene polymorphisms during 1 year. Genomic DNA was extracted by DNA extraction kit according to the manufacture's protocol. Polymerase chain reaction single-stranded conformation polymorphism (PCR-SSCP and silver staining were performed for investigating EGFR gene polymorphisms. Results : The participants included 72 men and 44 women. Gene polymorphism in exon 18 was present in 10% of the study population but SSCP pattern in exon 19 did not show different migrate bands neither in patients nor in normal subjects.Conclusion: It seems that screening for tyrosine kinas gene polymorphism of epidermal growth factor receptor in patients with gastric cancer and use of tyrosine kinas inhibitors could be useful in the prevention of disease progress and improvement of treatment process for a better quality of life in these patients.

  15. Therapy for acute pancreatitis with platelet-activating factor receptor antagonists

    Institute of Scientific and Technical Information of China (English)

    Chong Chen; Shi-Hai Xia; Hong Chen; Xiao-Hong Li

    2008-01-01

    Acute pancreatitis (AP) causes release of plateletactivating factor (PAF),which induces systemic effects that contribute to circulatory disturbances and multiple organ failure.PAF is a cell surface secretion of bioactive lipid,which could produce physiological and pathological effects by binding to its cell surface receptor called platelet-activating factor receptor (PAF-R).Studies showed that PAF participates in the occurrence and development of AP and administration of platelet-activating factor receptor antagonists (PAF-RAs) could significantly reduce local and systemic events after AP.PAF has also been implicated as a key mediator in the progression of severe AP,which can lead to complications and unacceptably high mortality rates.Several classes of PAF-RA show PAFRAs significant local and systemic effects on reducing inflammatory changes.As a preventive treatment,PAF-RA could block a series of PAF-mediatedinflammatory injury and thus improve the prognosis of AR This review introduces the important role of PAF-RA in the treatment of AP.

  16. Dopamine receptor activation increases glial cell line-derived neurotrophic factor in experimental stroke.

    Science.gov (United States)

    Kuric, Enida; Wieloch, Tadeusz; Ruscher, Karsten

    2013-09-01

    Treatment with levodopa enhances functional recovery after experimental stroke but its mechanisms of action are elusive. Reactive astrocytes in the ischemic hemisphere are involved in mechanisms promoting recovery and also express dopamine 1 (D1) and dopamine 2 (D2) receptors. Here we investigated if the activation of astrocytic dopamine receptors (D1 and D2) regulates the expression of glial cell line-derived neurotrophic factor (GDNF) after combined in vitro hypoxia/aglycemia (H/A) and studied the expression of GDNF in the ischemic brain after treatment with levodopa/benserazide following transient occlusion of the middle cerebral artery (tMCAO) in the rat. Twenty-four hours after H/A, GDNF levels were upregulated in exposed astrocytes compared to normoxic control cultures and further elevated by the addition of the selective D1 receptor agonist (R)-(+)-SKF-38393 hydrochloride while D1 receptor antagonism by R(+)-SCH-23390 hydrochloride significantly reduced GDNF. No effect on GDNF levels was observed by the application of the D2 receptor agonist R(-)-2,10,11-trihydroxy-N-propyl-noraporphine hydrobromide hydrate or S-(-)-eticlopride hydrochloride (D2 receptor antagonist). After tMCAO, GDNF was upregulated in D1 expressing reactive astrocytes in the peri-infarct area. In addition, treatment with levodopa/benserazide significantly increased GDNF levels in the infarct core and peri-infarct area after tMCAO without affecting the expression of glial fibrillar acidic protein (GFAP), an intermediate filament and marker of reactive gliosis. After stroke, GDNF levels increase in the ischemic hemisphere in rats treated with levodopa, implicating GDNF in the mechanisms of tissue reorganization and plasticity and in l-DOPA enhanced recovery of lost brain function. Our results support levodopa treatment as a potential recovery enhancing therapy in stroke patients.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-06-30

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

  18. Metabotropic glutamate receptor 2 and corticotrophin-releasing factor receptor-1 gene expression is differently regulated by BDNF in rat primary cortical neurons

    DEFF Research Database (Denmark)

    Jørgensen, Christinna V; Klein, Anders B; El-Sayed, Mona;

    2013-01-01

    Brain-derived neurotrophic factor (BDNF) is important for neuronal survival and plasticity. Incorporation of matured receptor proteins is an integral part of synapse formation. However, whether BDNF increases synthesis and integration of receptors in functional synapses directly is unclear. We...... are particularly interested in the regulation of the 5-hydroxytryptamine receptor 2A (5-HT2A R). This receptor form a functional complex with the metabotropic glutamate receptor 2 (mGluR2) and is recruited to the cell membrane by the corticotrophin-releasing factor receptor 1 (CRF-R1). The effect of BDNF on gene...... expression for all these receptors, as well as a number of immediate-early genes, was pharmacologically characterized in primary neurons from rat frontal cortex. BDNF increased CRF-R1 mRNA levels up to fivefold, whereas mGluR2 mRNA levels were proportionally downregulated. No effect on 5-HT2A R mRNA was seen...

  19. Dynamic changes in the expression of growth factor receptors in the myocardium microvascular endothelium after murine myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    WANG Xin-hong; ZHANG Guo-ping; JIN Hui-ming; CHEN Si-feng

    2007-01-01

    Background After myocardial infarction, specific growth factors promote cardiac angiogenisis, leading to a therapeutic effect. Although this effect is mediated by specific receptors in the endothelium of the cardiac microvasculature, few studies have investigated dynamic changes in their expression. We explored this phenomenon in a murine model.Methods We observed the mRNA expression of receptors by specific angiogenesis gene microarray at day 3 and day 7after infarction. The vascular endothelial growth factor (VEGF) receptor Fik-1 was observed at the protein level at day 3and day 7 by immunohistochemistry. The dynamic expression of fibroblast growth factor receptor-1 (FGFR-1) mRNA in the border zone and the noninfarcted zone at day 3, day 7, day 14, and day 42 was investigated by real-time PCR.Statistical significance was analyzed with SPSS 10.0 software using one-way analysis of variance (ANOVA).Results Three days after infarction, 9 receptors in the border zone and 7 receptors in the noninfarcted zone were down-regulated. Two receptors in the infarct edge and 5 receptors in the distant myocardium were up-regulated. However,at day 7, 11 receptors in the border zone were up-regulated, and only one was down-regulated. In the border zone, Fik-1levels decreased at day 3 but increased significantly at day 7. Real-time PCR showed that FGFR-1 mRNA decreased markedly in the border zone at day 3 but increased afterward for at least 6 weeks. In the early stage (3 days) after infarction, the expression of receptors had decreased to some extent. However, at day 7, receptor expression was active and had moved from the distant noninfarcted zone to the border zone as a part of the acute repair process.Conclusion Selecting the proper growth factors to target receptors with protective activity, and determining appropriate therapeutic timing may be important to the success of therapeutic angiogenesis.

  20. The structure and function of vertebrate fibroblast growth factor receptor 1.

    Science.gov (United States)

    Groth, Casper; Lardelli, Michael

    2002-01-01

    The vertebrate fibroblast growth factor receptor 1 (FGFR1) is alternatively spliced generating multiple splice variants that are differentially expressed during embryo development and in the adult body. The restricted expression patterns of FGFR1 isoforms, together with differential expression and binding of specific ligands, leads to activation of common FGFR1 signal transduction pathways, but may result in distinctively different biological responses as a result of differences in cellular context. FGFR1 isoforms are also present in the nucleus in complex with various fibroblast growth factors where they function to regulate transcription of target genes.

  1. Proteinuria, a modifiable risk factor: angiotensin converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs).

    Science.gov (United States)

    Dykeman-Sharpe, Jennifer

    2003-01-01

    Microalbuminuria and proteinuria have been determined to be modifiable risk factors for the progression of chronic kidney disease as well as risk factors for cardiovascular events. Angiotensin converting enzyme inhibitors and angiotensin II receptor blockers have been demonstrated to decrease proteinuria at all stages and slow the progression of renal disease. Proteinuria can be used as a marker of successful treatment in patients with chronic kidney disease in combination with other established targets. This article discusses the various diagnostic tests used for the detection of microalbuminuria and proteinuria and appropriate pharmaceutical treatment.

  2. Genistein enhances the effect of trichostatin A on inhibition of A549 cell growth by increasing expression of TNF receptor-1

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Tzu-Chin [Chest Clinic, Chung Shan Medical University Hospital, Taichung, Taiwan, ROC (China); Yang, Ying-Chihi; Huang, Pei-Ru [Department of Nutritional Science, Chung Shan Medical University, Taichung, Taiwan, ROC (China); Wen, Yu-Der [Department of Biology, National Changhua University of Education, Changhua, Taiwan, ROC (China); Yeh, Shu-Lan, E-mail: suzyyeh@csmu.edu.tw [Department of Nutritional Science, Chung Shan Medical University, Taichung, Taiwan, ROC (China); Department of Nutrition, Chung Shan Medical University Hospital, Taichung, Taiwan, ROC (China)

    2012-08-01

    Our previous study has shown that genistein enhances apoptosis in A549 lung cancer cells induced by trichostatin A (TSA). The precise molecular mechanism underlying the effect of genistein, however, remains unclear. In the present study, we investigated whether genistein enhances the anti-cancer effect of TSA through up-regulation of TNF receptor-1 (TNFR-1) death receptor signaling. We incubated A549 cells with TSA (50 ng/mL) alone or in combination with genistein and then determined the mRNA and protein expression of TNFR-1 as well as the activation of downstream caspases. Genistein at 5 and 10 μM significantly enhanced the TSA-induced decrease in cell number and apoptosis in a dose-dependent manner. The combined treatment significantly increased mRNA and protein expression of TNFR-1 at 6 and 12 h, respectively, compared with that of the control group; while TSA alone had no effect. TSA in combination with 10 μM of genistein increased TNFR-1 mRNA and protein expression by about 70% and 40%, respectively. The underlying mechanism for this effect of genistein may be partly associated with the estrogen receptor pathway. The combined treatment also increased the activation of caspase-3 and ‐10 as well as p53 protein expression in A549 cells. The enhancing effects of genistein on the TSA-induced decrease in cell number and on the expression of caspase-3 in A549 cells were suppressed by silencing TNFR-1 expression. These data demonstrated that the upregulation of TNFR-1 death receptor signaling plays an important role, at least in part, in the enhancing effect of genistein on TSA-induced apoptosis in A549 cells. -- Highlights: ► TSA combined with genistein rather than TSA alone increases the expression of TNFR-1. ► Genistein may exert such an effect partly through estrogen receptor pathway. ► The combined treatment increases the activation of caspase-10 and caspase-3. ► The combined treatment also increases the expression of p53 protein. ► TNFR-1 si

  3. Therapeutic targeting of epidermal growth factor receptor in human cancer: successes and limitations%Therapeutic targeting of epidermal growth factor receptor in humancancer: successes and limitations

    Institute of Scientific and Technical Information of China (English)

    Jill Wykosky; Tim Fenton; Frank Furnari; Webster K. Cavenee

    2011-01-01

    Epidermal growth factor receptor (EGFR) is one of the most commonly altered genes in human cancer by way of over-expression, amplification, and mutation. Targeted inhibition of EGFR activity suppresses signal transduction pathways which control tumor cell growth, proliferation, and resistance to apoptosis. Small molecule tyrosine kinase inhibitors and monoclonal antibodies are among the most common EGFR-targeting agents and have been used clinically for treating various malignancies. This review discusses the successes and challenges of targeting EGFR in human cancer. The genetic alterations of EGFR tend to occur more often in some solid tumors than others, as do the mechanisms of resistance to targeted inhibition. The clinical and basic science experiences with these agents thus far have important implications for the future of therapeutic targeting of EGFR.

  4. The Role of Epidermal Growth Factor Receptor Mutations and Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitors in the Treatment of Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Shih-Chieh [Department of Internal Medicine, National Yang-Ming University Hospital, Yilan 260, Taiwan (China); Chang, Cheng-Yu [Department of Chest Medicine, Far Eastern Memorial Hospital, Taipei 220, Taiwan (China); Shih, Jin-Yuan, E-mail: jyshih@ntu.edu.tw [Department of Internal Medicine, National Taiwan University Hospital and College of Medicine, National Taiwan University, Taipei 100, Taiwan (China)

    2011-06-10

    Lung cancer is the leading cause of cancer-related deaths worldwide. Non-small-cell lung cancer (NSCLC) cases comprise approximately 85% of the lung cancer cases. Before the era of target therapy, platinum-based doublet chemotherapy only led to a median survival of 8–9 months and a one-year survival of 30%–40% in patients with advanced NSCLC. In July 2002, gefitinib, a small-molecule epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI), was approved for the treatment of patients with advanced NSCLC in Japan. After the widespread use of gefitinib in the treatment of NSCLC, there have been many new studies regarding the association between the clinical anticancer efficacy of gefitinib and the somatic EGFR mutation status in patients with NSCLC. This article summarizes the role of EGFR mutations in lung cancer and the use of EGFR antagonists in the treatment of lung cancer and its associated adverse effects.

  5. TLR4 and CD14 receptors expressed in rat pineal gland trigger NFKB pathway.

    Science.gov (United States)

    da Silveira Cruz-Machado, Sanseray; Carvalho-Sousa, Claudia Emanuele; Tamura, Eduardo Koji; Pinato, Luciana; Cecon, Erika; Fernandes, Pedro Augusto Carlos Magno; de Avellar, Maria Christina Werneck; Ferreira, Zulma Silva; Markus, Regina Pekelmann

    2010-09-01

    Nuclear factor-kappa B (NFKB), a pivotal player in inflammatory responses, is constitutively expressed in the pineal gland. Corticosterone inhibits pineal NFKB leading to an enhancement of melatonin production, while tumor necrosis factor (TNF) leads to inhibition of Aa-nat transcription and the production of N-acetylserotonin in cultured glands. The reduction in nocturnal melatonin surge favors the mounting of the inflammatory response. Despite these data, there is no clear evidence of the ability of the pineal gland to recognize molecules that signal infection. This study investigated whether the rat pineal gland expresses receptors for lipopolysaccharide (LPS), the endotoxin from the membranes of Gram-negative bacteria, and to establish the mechanism of action of LPS. Here, we show that pineal glands possess both CD14 and toll-like receptor 4 (TLR4), membrane proteins that bind LPS and trigger the NFKB pathway. LPS induced the nuclear translocation of p50/p50 and p50/RELA dimers and the synthesis of TNF. The maximal expression of TNF in cultured glands coincides with an increase in the expression of TNF receptor 1 (TNFR1) in isolated pinealocytes. In addition, LPS inhibited the synthesis of N-acetylserotonin and melatonin. Therefore, the pineal gland transduces Gram-negative endotoxin stimulation by producing TNF and inhibiting melatonin synthesis. Here, we provide evidence to reinforce the idea of an immune-pineal axis, showing that the pineal gland is a constitutive player in the innate immune response.

  6. Identification of fibroblast growth factor receptor 3 (FGFR3 as a protein receptor for botulinum neurotoxin serotype A (BoNT/A.

    Directory of Open Access Journals (Sweden)

    Birgitte P S Jacky

    Full Text Available Botulinum neurotoxin serotype A (BoNT/A causes transient muscle paralysis by entering motor nerve terminals (MNTs where it cleaves the SNARE protein Synaptosomal-associated protein 25 (SNAP25206 to yield SNAP25197. Cleavage of SNAP25 results in blockage of synaptic vesicle fusion and inhibition of the release of acetylcholine. The specific uptake of BoNT/A into pre-synaptic nerve terminals is a tightly controlled multistep process, involving a combination of high and low affinity receptors. Interestingly, the C-terminal binding domain region of BoNT/A, HC/A, is homologous to fibroblast growth factors (FGFs, making it a possible ligand for Fibroblast Growth Factor Receptors (FGFRs. Here we present data supporting the identification of Fibroblast Growth Factor Receptor 3 (FGFR3 as a high affinity receptor for BoNT/A in neuronal cells. HC/A binds with high affinity to the two extra-cellular loops of FGFR3 and acts similar to an agonist ligand for FGFR3, resulting in phosphorylation of the receptor. Native ligands for FGFR3; FGF1, FGF2, and FGF9 compete for binding to FGFR3 and block BoNT/A cellular uptake. These findings show that FGFR3 plays a pivotal role in the specific uptake of BoNT/A across the cell membrane being part of a larger receptor complex involving ganglioside- and protein-protein interactions.

  7. Identification of fibroblast growth factor receptor 3 (FGFR3 as a protein receptor for botulinum neurotoxin serotype A (BoNT/A.

    Directory of Open Access Journals (Sweden)

    Birgitte P S Jacky

    Full Text Available Botulinum neurotoxin serotype A (BoNT/A causes transient muscle paralysis by entering motor nerve terminals (MNTs where it cleaves the SNARE protein Synaptosomal-associated protein 25 (SNAP25206 to yield SNAP25197. Cleavage of SNAP25 results in blockage of synaptic vesicle fusion and inhibition of the release of acetylcholine. The specific uptake of BoNT/A into pre-synaptic nerve terminals is a tightly controlled multistep process, involving a combination of high and low affinity receptors. Interestingly, the C-terminal binding domain region of BoNT/A, HC/A, is homologous to fibroblast growth factors (FGFs, making it a possible ligand for Fibroblast Growth Factor Receptors (FGFRs. Here we present data supporting the identification of Fibroblast Growth Factor Receptor 3 (FGFR3 as a high affinity receptor for BoNT/A in neuronal cells. HC/A binds with high affinity to the two extra-cellular loops of FGFR3 and acts similar to an agonist ligand for FGFR3, resulting in phosphorylation of the receptor. Native ligands for FGFR3; FGF1, FGF2, and FGF9 compete for binding to FGFR3 and block BoNT/A cellular uptake. These findings show that FGFR3 plays a pivotal role in the specific uptake of BoNT/A across the cell membrane being part of a larger receptor complex involving ganglioside- and protein-protein interactions.

  8. Tissue-specific pioneer factors associate with androgen receptor cistromes and transcription programs

    Science.gov (United States)

    Pihlajamaa, Päivi; Sahu, Biswajyoti; Lyly, Lauri; Aittomäki, Viljami; Hautaniemi, Sampsa; Jänne, Olli A

    2014-01-01

    Androgen receptor (AR) binds male sex steroids and mediates physiological androgen actions in target tissues. ChIP-seq analyses of AR-binding events in murine prostate, kidney and epididymis show that in vivo AR cistromes and their respective androgen-dependent transcription programs are highly tissue specific mediating distinct biological pathways. This high order of tissue specificity is achieved by the use of exclusive collaborating factors in the three androgen-responsive tissues. We find two novel collaborating factors for AR signaling in vivo—Hnf4α (hepatocyte nuclear factor 4α) in mouse kidney and AP-2α (activating enhancer binding protein 2α) in mouse epididymis—that define tissue-specific AR recruitment. In mouse prostate, FoxA1 serves for the same purpose. FoxA1, Hnf4α and AP-2α motifs are over-represented within unique AR-binding loci, and the cistromes of these factors show substantial overlap with AR-binding events distinct to each tissue type. These licensing or pioneering factors are constitutively bound to chromatin and guide AR to specific genomic loci upon hormone exposure. Collectively, liganded receptor and its DNA-response elements are required but not sufficient for establishment of tissue-specific transcription programs. PMID:24451200

  9. Platelet-derived growth factors and their receptors in normal and malignant hematopoiesis

    Science.gov (United States)

    Demoulin, Jean-Baptiste; Montano-Almendras, Carmen P.

    2012-01-01

    Platelet-derived growth factors (PDGF) bind to two closely related receptor tyrosine kinases, PDGF receptor α and β, which are encoded by the PDGFRA and PDGFRB genes. Aberrant activation of PDGF receptors occurs in myeloid malignancies associated with hypereosinophilia, due to chromosomal alterations that produce fusion genes, such as ETV6-PDGFRB or FIP1L1-PDGFRA. Most patients are males and respond to low dose imatinib, which is particularly effective against PDGF receptor kinase activity. Recently, activating point mutations in PDGFRA were also described in hypereosinophilia. In addition, autocrine loops have been identified in large granular lymphocyte leukemia and HTLV-transformed lymphocytes, suggesting new possible indications for tyrosine kinase inhibitor therapy. Although PDGF was initially purified from platelets more than 30 years ago, its physiological role in the hematopoietic system remains unclear. Hematopoietic defects in PDGF-deficient mice have been reported but appear to be secondary to cardiovascular and placental abnormalities. Nevertheless, PDGF acts directly on several hematopoietic cell types in vitro, such as megakaryocytes, platelets, activated macrophages and, possibly, certain lymphocyte subsets and eosinophils. The relevance of these observations for normal human hematopoiesis remains to be established. PMID:22432087

  10. Receptor binding sites for atrial natriuretic factor are expressed by brown adipose tissue

    Energy Technology Data Exchange (ETDEWEB)

    Bacay, A.C.; Mantyh, C.R.; Vigna, S.R.; Mantyh, P.W. (Wadsworth VA Medical Center, Los Angeles, CA (USA))

    1988-09-01

    To explore the possibility that atrial natriuretic factor (ANF) is involved in thermoregulation we used quantitative receptor autoradiography and homogenate receptor binding assays to identify ANF bindings sites in neonatal rat and sheep brown adipose tissue, respectively. Using quantitative receptor autoradiography were were able to localize high levels of specific binding sites for {sup 125}I-rat ANF in neonatal rat brown adipose tissue. Homogenate binding assays on sheep brown fat demonstrated that the radioligand was binding to the membrane fraction and that the specific binding was not due to a lipophilic interaction between {sup 125}I-rat ANF and brown fat. Specific binding of {sup 125}I-rat ANF to the membranes of brown fat cells was inhibited by unlabeled rat ANF with a Ki of 8.0 x 10(-9) M, but not by unrelated peptides. These studies demonstrate that brown fat cells express high levels of ANF receptor binding sites in neonatal rat and sheep and suggest that ANF may play a role in thermoregulation.

  11. Exchange factors directly activated by cAMP mediate melanocortin 4 receptor-induced gene expression

    Science.gov (United States)

    Glas, Evi; Mückter, Harald; Gudermann, Thomas; Breit, Andreas

    2016-01-01

    Gs protein-coupled receptors regulate many vital body functions by activation of cAMP response elements (CRE) via cAMP-dependent kinase A (PKA)-mediated phosphorylation of the CRE binding protein (CREB). Melanocortin 4 receptors (MC4R) are prototypical Gs-coupled receptors that orchestrate the hypothalamic control of food-intake and metabolism. Remarkably, the significance of PKA for MC4R-induced CRE-dependent transcription in hypothalamic cells has not been rigorously interrogated yet. In two hypothalamic cell lines, we observed that blocking PKA activity had only weak or no effects on reporter gene expression. In contrast, inhibitors of exchange factors directly activated by cAMP-1/2 (EPAC-1/2) mitigated MC4R-induced CRE reporter activation and mRNA induction of the CREB-dependent genes c-fos and thyrotropin-releasing hormone. Furthermore, we provide first evidence that extracellular-regulated kinases-1/2 (ERK-1/2) activated by EPACs and not PKA are the elusive CREB kinases responsible for MC4R-induced CREB/CRE activation in hypothalamic cells. Overall, these data emphasize the pivotal role of EPACs rather than PKA in hypothalamic gene expression elicited by a prototypical Gs-coupled receptor. PMID:27612207

  12. Fibroblast growth factor receptor signaling is essential for lens fiber cell differentiation.

    Science.gov (United States)

    Zhao, Haotian; Yang, Tianyu; Madakashira, Bhavani P; Thiels, Cornelius A; Bechtle, Chad A; Garcia, Claudia M; Zhang, Huiming; Yu, Kai; Ornitz, David M; Beebe, David C; Robinson, Michael L

    2008-06-15

    The vertebrate lens provides an excellent model to study the mechanisms that regulate terminal differentiation. Although fibroblast growth factors (FGFs) are thought to be important for lens cell differentiation, it is unclear which FGF receptors mediate these processes during different stages of lens development. Deletion of three FGF receptors (Fgfr1-3) early in lens development demonstrated that expression of only a single allele of Fgfr2 or Fgfr3 was sufficient for grossly normal lens development, while mice possessing only a single Fgfr1 allele developed cataracts and microphthalmia. Profound defects were observed in lenses lacking all three Fgfrs. These included lack of fiber cell elongation, abnormal proliferation in prospective lens fiber cells, reduced expression of the cell cycle inhibitors p27(kip1) and p57(kip2), increased apoptosis and aberrant or reduced expression of Prox1, Pax6, c-Maf, E-cadherin and alpha-, beta- and gamma-crystallins. Therefore, while signaling by FGF receptors is essential for lens fiber differentiation, different FGF receptors function redundantly.

  13. Molecular Recognition of Corticotropin releasing Factor by Its G protein-coupled Receptor CRFR1

    Energy Technology Data Exchange (ETDEWEB)

    Pioszak, Augen A.; Parker, Naomi R.; Suino-Powell, Kelly; Xu, H. Eric (Van Andel)

    2009-01-15

    The bimolecular interaction between corticotropin-releasing factor (CRF), a neuropeptide, and its type 1 receptor (CRFR1), a class B G-protein-coupled receptor (GPCR), is crucial for activation of the hypothalamic-pituitary-adrenal axis in response to stress, and has been a target of intense drug design for the treatment of anxiety, depression, and related disorders. As a class B GPCR, CRFR1 contains an N-terminal extracellular domain (ECD) that provides the primary ligand binding determinants. Here we present three crystal structures of the human CRFR1 ECD, one in a ligand-free form and two in distinct CRF-bound states. The CRFR1 ECD adopts the alpha-beta-betaalpha fold observed for other class B GPCR ECDs, but the N-terminal alpha-helix is significantly shorter and does not contact CRF. CRF adopts a continuous alpha-helix that docks in a hydrophobic surface of the ECD that is distinct from the peptide-binding site of other class B GPCRs, thereby providing a basis for the specificity of ligand recognition between CRFR1 and other class B GPCRs. The binding of CRF is accompanied by clamp-like conformational changes of two loops of the receptor that anchor the CRF C terminus, including the C-terminal amide group. These structural studies provide a molecular framework for understanding peptide binding and specificity by the CRF receptors as well as a template for designing potent and selective CRFR1 antagonists for therapeutic applications.

  14. Structural analysis of the receptors for granulocyte colony-stimulating factor on neutrophils

    Energy Technology Data Exchange (ETDEWEB)

    Hanazono, Y.; Hosoi, T.; Kuwaki, T.; Matsuki, S.; Miyazono, K.; Miyagawa, K.; Takaku, F. (Univ. of Tokyo (Japan))

    1990-11-01

    We investigated granulocyte colony-stimulating factor (G-CSF) receptors on neutrophils from three patients with chronic myelogenous leukemia (CML) in the chronic phase, in comparison with four normal volunteers. Because we experienced some difficulties in radioiodinating intact recombinant human G-CSF, we developed a new derivative of human G-CSF termed YPY-G-CSF. It was easy to iodinate this protein using the lactoperoxidase method because of two additional tyrosine residues, and its radioactivity was higher than that previously reported. The biological activity of YPY-G-CSF as G-CSF was fully retained. Scatchard analysis demonstrated that CML neutrophils had a single class of binding sites (1400 +/- 685/cell) with a dissociation constant (Kd) of 245 +/- 66 pM. The number of sites and Kd value of CML neutrophils were not significantly different from those of normal neutrophils (p greater than 0.9). Cross-linking studies revealed two specifically labeled bands of (125I)YPY-G-CSF-receptor complexes with apparent molecular masses of 160 and 110 kd on both normal and CML neutrophils. This is the first report describing two receptor proteins on neutrophils. According to the analyses of the proteolytic process of these cross-linked complexes and proteolytic mapping, we assume that alternative splicing or processing from a single gene may generate two distinct receptor proteins that bind specifically to G-CSF but have different fates in intracellular metabolism.

  15. Expression and autoregulation of transforming growth factor beta receptor mRNA in small-cell lung cancer cell lines

    DEFF Research Database (Denmark)

    Nørgaard, P; Spang-Thomsen, M; Poulsen, H S

    1996-01-01

    In small-cell lung cancer cell lines resistance to growth inhibition by transforming growth factor (TGF)-beta 1, was previously shown to correlate with lack of TGF-beta receptor I (RI) and II (RII) proteins. To further investigate the role of these receptors, the expression of mRNA for RI, RII...

  16. Germ cell nuclear factor directly represses the transcription of peroxisome proliferator-activated receptor delta gene

    Institute of Scientific and Technical Information of China (English)

    Chengqiang He; Naizheng Ding; Jie Kang

    2008-01-01

    Germ cell nuclear factor (GCNF) is a transcription factor that can repress gene transcription and plays an important role during spermatogenesis. Peroxisome proliferator-activated receptor delta (PPARδ) is a nuclear hormone receptor belonging to the steroid receptor superfamily.It can activate the expression of many genes,including those involved in lipid metabolism.In this report,we showed that GCNF specifically interacts with PPARδ promoter.Overexpression of GCNF in African green monkey SV40 transformed kidney fibroblast COS7 cells and mouse embryo fibroblast NIH 3T3 cells represses the activity of PPARδ promoter.The mutation of GCNF response element in PPARδ promoter relieves the repression in NIH 3T3 cells and mouse testis.Moreover,we showed that GCNF in nuclear extracts of mouse testis is able to bind to PPARδ promoter directly.We also found that GCNF and PPARδ mRNA were expressed with different patterns in mouse testis by in situ hybridization.These results suggested that GCNF might be a negative regulator of PPARδ gene expression through its direct interaction with PPARδ promoter in mouse testis.

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

    Institute of Scientific and Technical Information of China (English)

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

    2005-01-01

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

  18. Surface proteome analysis identifies platelet derived growth factor receptor-alpha as a critical mediator of transforming growth factor-beta-induced collagen secretion.

    Science.gov (United States)

    Heinzelmann, Katharina; Noskovičová, Nina; Merl-Pham, Juliane; Preissler, Gerhard; Winter, Hauke; Lindner, Michael; Hatz, Rudolf; Hauck, Stefanie M; Behr, Jürgen; Eickelberg, Oliver

    2016-05-01

    Fibroblasts are extracellular matrix-producing cells in the lung. Fibroblast activation by transforming growth factor-beta leads to myofibroblast-differentiation and increased extracellular matrix deposition, a hallmark of pulmonary fibrosis. While fibroblast function with respect to migration, invasion, and extracellular matrix deposition has been well-explored, little is known about the surface proteome of lung fibroblasts in general and its specific response to fibrogenic growth factors, in particular transforming growth factor-beta. We thus performed a cell-surface proteome analysis of primary human lung fibroblasts in presence/absence of transforming growth factor-beta, followed by characterization of our findings using FACS analysis, Western blot, and siRNA-mediated knockdown experiments. We identified 213 surface proteins significantly regulated by transforming growth factor-beta, platelet derived growth factor receptor-alpha being one of the top down-regulated proteins. Transforming growth factor beta-induced downregulation of platelet derived growth factor receptor-alpha induced upregulation of platelet derived growth factor receptor-beta expression and phosphorylation of Akt, a downstream target of platelet derived growth factor signaling. Importantly, collagen type V expression and secretion was strongly increased after forced knockdown of platelet derived growth factor receptor-alpha, an effect that was potentiated by transforming growth factor-beta. We therefore show previously underappreciated cross-talk of transforming growth factor-beta and platelet derived growth factor signaling in human lung fibroblasts, resulting in increased extracellular matrix deposition in a platelet derived growth factor receptor-alpha dependent manner. These findings are of particular importance for the treatment of lung fibrosis patients with high pulmonary transforming growth factor-beta activity.

  19. Advanced Research of Fibroblast Growth Factor Receptor 
in Non-small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Dan PU

    2013-11-01

    Full Text Available Lung cancer is severely threatening human health. In recent years, the treatment for lung adenocarcinoma has made a great progress, targeted therapy has been widely applied in clinic, and benefits amount of patients. However, in squamous cell lung cancer, the incidence of epidermal growth factor receptor (EGFR gene mutant and ALK fusion gene are low,and targeted therapy like Tarceva and crizotinib, can hardly work. Since the fibroblast growth factors (fibroblast growth factor, FGF pathway is considered to be related to tumor cell proliferation, metastasis and angiogenesis, more and more researches proved the amplification of fibroblast growth factor receptor (FGFR in squamous cell lung cancer. Experiments in vivo and in vitro found that blocking FGF pathway could reduce the proliferation of tumor cells and inhibit metastasis. The FGF pathway might be a new target for treatment of squamous cell lung cancer. This article reviews the effect of FGFR in tumorigenesis,as well as the prospect as a therapeutic target in non-small cell lung cancer.

  20. Receptor Signaling Directs Global Recruitment of Pre-existing Transcription Factors to Inducible Elements

    Science.gov (United States)

    Cockerill, Peter N.

    2016-01-01

    Gene expression programs are largely regulated by the tissue-specific expression of lineage-defining transcription factors or by the inducible expression of transcription factors in response to specific stimuli. Here I will review our own work over the last 20 years to show how specific activation signals also lead to the wide-spread re-distribution of pre-existing constitutive transcription factors to sites undergoing chromatin reorganization. I will summarize studies showing that activation of kinase signaling pathways creates open chromatin regions that recruit pre-existing factors which were previously unable to bind to closed chromatin. As models I will draw upon genes activated or primed by receptor signaling in memory T cells, and genes activated by cytokine receptor mutations in acute myeloid leukemia. I also summarize a hit-and-run model of stable epigenetic reprograming in memory T cells, mediated by transient Activator Protein 1 (AP-1) binding, which enables the accelerated activation of inducible enhancers. PMID:28018147

  1. Oxidatively fragmented phosphatidylcholines activate human neutrophils through the receptor for platelet-activating factor.

    Science.gov (United States)

    Smiley, P L; Stremler, K E; Prescott, S M; Zimmerman, G A; McIntyre, T M

    1991-06-15

    Platelet-activating factor (PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) activates neutrophils (polymorphonuclear leukocytes, PMN) through a receptor that specifically recognizes short sn-2 residues. We oxidized synthetic [2-arachidonoyl]phosphatidylcholine to fragment and shorten the sn-2 residue, and then examined the phospholipid products for the ability to stimulate PMN. 1-Palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine was fragmented by ozonolysis to 1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphocholine. This phospholipid activated human neutrophils at submicromolar concentrations, and is effects were inhibited by specific PAF receptor antagonists WEB2086, L659,989, and CV3988. 1-Palmitoyl-2-arachidonoyl-sn-glycero-3-phosphocholine next was fragmented by an uncontrolled free radical-catalyzed reaction: it was treated with soybean lipoxygenase to form its sn-2 15-hydroperoxy derivative (which did not activate neutrophils) and then allowed to oxidize under air. The secondary oxidation resulted in the formation of numerous fragmented phospholipids (Stremler, K. E., Stafforini, D. M., Prescott, S. M., and McIntyre, T. M. (1991) J. Biol. Chem. 266, 11095-11103), some of which activated PMN. Hydrolysis of sn-2 residues with phospholipase A2 destroyed biologic activity, as did hydrolysis with PAF acetylhydrolase. PAF acetylhydrolase is specific for short or intermediate length sn-2 residues and does not hydrolyze the starting material (Stremler, K. E., Stafforini, D. M., Prescott, S. M., and McIntyre, T. M. (1991) J. Biol. Chem. 266, 11095-11103). Neutrophil activation was completely blocked by L659,989, a specific PAF receptor antagonist. We conclude that diacylphosphatidylcholines containing an sn-2 polyunsaturated fatty acyl residue can be oxidatively fragmented to species with sn-2 residues short enough to activate the PAF receptor of neutrophils. This suggests a new mechanism for the appearance of biologically active phospholipids, and shows

  2. Epidermal growth factor receptor in the prawn Macrobrachium rosenbergii: function and putative signaling cascade.

    Science.gov (United States)

    Sharabi, Omri; Ventura, Tomer; Manor, Rivka; Aflalo, Eliahu D; Sagi, Amir

    2013-09-01

    Epidermal growth factor receptors (EGFRs) are highly conserved members of the tyrosine kinase receptor superfamily found in metazoans and plants. In arthropods, EGFRs are vital for the proper development of embryos and of adult limbs, gonads, and eyes as well as affecting body size. In searching for genes involved in the growth and development of our model organism, the decapod crustacean (Macrobrachium rosenbergii), a comprehensive transcript library was established using next-generation sequencing. Using this library, the expression of several genes assigned to the signal transduction pathways mediated by EGFRs was observed, including a transcript encoding M. rosenbergii EGFR (Mr-EGFR), several potential ligands upstream to the receptor, and most of the putative downstream signal transducer genes. The deduced protein encoded by Mr-EGFR, representing the first such receptor reported thus far in crustaceans, shows sequence similarity to other arthropod EGFRs. The M. rosenbergii gene is expressed in most tested tissues. The role of Mr-EGFR was revealed by temporarily silencing the transcript through weekly injections of double-stranded Mr-EGFR RNA. Such treatment resulted in a significant reduction in growth and a delay in the appearance of a male secondary sexual characteristic, namely the appendix masculina. An additional function of Mr-EGFR was revealed with respect to eye development. Although the optic ganglion appeared to have retained its normal morphology, Mr-EGFR-silenced individuals developed abnormal eyes that presented irregular organization of the ommatidia, reflected by unorganized receptor cells occupying large areas of the dioptric portion and by a shortened crystalline tract layer.

  3. Molecular assembly of the ternary granulocyte-macrophage colony-stimulating factor receptor complex.

    Science.gov (United States)

    McClure, Barbara J; Hercus, Timothy R; Cambareri, Bronwyn A; Woodcock, Joanna M; Bagley, Christopher J; Howlett, Geoff J; Lopez, Angel F

    2003-02-15

    Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a hematopoietic cytokine that stimulates the production and functional activity of granulocytes and macrophages, properties that have encouraged its clinical use in bone marrow transplantation and in certain infectious diseases. Despite the importance of GM-CSF in regulating myeloid cell numbers and function, little is known about the exact composition and mechanism of assembly of the GM-CSF receptor complex. We have now produced soluble forms of the GM-CSF receptor alpha chain (sGMRalpha) and beta chain (sbetac) and utilized GM-CSF, the GM-CSF antagonist E21R (Glu21Arg), and the betac-blocking monoclonal antibody BION-1 to define the molecular assembly of the GM-CSF receptor complex. We found that GM-CSF and E21R were able to form low-affinity, binary complexes with sGMRalpha, each having a stoichiometry of 1:1. Importantly, GM-CSF but not E21R formed a ternary complex with sGMRalpha and sbetac, and this complex could be disrupted by E21R. Significantly, size-exclusion chromatography, analytical ultracentrifugation, and radioactive tracer experiments indicated that the ternary complex is composed of one sbetac dimer with a single molecule each of sGMRalpha and of GM-CSF. In addition, a hitherto unrecognized direct interaction between betac and GM-CSF was detected that was absent with E21R and was abolished by BION-1. These results demonstrate a novel mechanism of cytokine receptor assembly likely to apply also to interleukin-3 (IL-3) and IL-5 and have implications for our molecular understanding and potential manipulation of GM-CSF activation of its receptor.

  4. Expression of fibroblast growth factor (FGF)-8 isoforms and FGF receptors in human ovarian tumors.

    Science.gov (United States)

    Valve, E; Martikainen, P; Seppänen, J; Oksjoki, S; Hinkka, S; Anttila, L; Grenman, S; Klemi, P; Härkönen, P

    2000-12-01

    FGF-8 is a mitogenic growth factor, which is widely expressed during embryonic development but only at a very low level in adult tissues. Alternative splicing of the human FGF-8 gene potentially allows coding for 4 protein isoforms (a, b, e, f), which differ in their transforming capacity. The FGF-8 isoforms preferentially activate the receptors FGFR1IIIc, FGFR2IIIc, FGFR3IIIc and FGFR4. FGF-8 is over-expressed in human breast and prostate cancers. Expression has also been found in RT-PCR studies of human ovarian and testicular cancers. The present study was undertaken to examine which FGF-8 isoforms are expressed in ovarian cancer and whether FGF-8 receptors are also expressed. Specimens from 5 normal human ovaries and 51 ovarian tumors (1 benign tumor, 8 borderline malignancies, 42 malignant tumors of different histopathological types) were studied by RT-PCR and immunohistochemistry. FGF-8 isoform b was expressed in all ovarian tumors and in all 7 ovarian-cancer cell lines studied. Isoform a was co-expressed in 9 malignant ovarian tumors. FGF-8 mRNA was not detected by RT-PCR of 3 normal ovary samples. Immunohistochemical staining localized FGF-8 protein to cancer cells. In general, the increased intensity of FGF-8 staining was associated with loss of differentiation within the tumors (Bowker's test, p = 0.37). FGF-8 staining of surface epithelium observed on 2 normal ovaries was very faint. RT-PCR showed that FGFR1IIIc, FGFR2IIIc and FGFR4 were the FGF-8 receptors expressed in normal ovaries and in ovarian tumors. FGF-8 receptor immunoreactivity was preferentially found in normal ovary surface epithelium and tumor cells but also in some stromal cells. Collectively, our results show that ovarian cancers of a wide variety of histological types expressing receptors for FGF-8 have acquired the capacity of expressing FGF-8. This suggests that FGF-8 has an important role in ovarian tumorigenesis.

  5. Epidermal Growth Factor Receptor-Dependent Mutual Amplification between Netrin-1 and the Hepatitis C Virus.

    Directory of Open Access Journals (Sweden)

    Marie-Laure Plissonnier

    2016-03-01

    Full Text Available Hepatitis C virus (HCV is an oncogenic virus associated with the onset of hepatocellular carcinoma (HCC. The present study investigated the possible link between HCV infection and Netrin-1, a ligand for dependence receptors that sustains tumorigenesis, in particular in inflammation-associated tumors. We show that Netrin-1 expression is significantly elevated in HCV+ liver biopsies compared to hepatitis B virus (HBV+ and uninfected samples. Furthermore, Netrin-1 was upregulated in all histological stages of HCV+ hepatic lesions, from minimal liver fibrosis to cirrhosis and HCC, compared to histologically matched HCV- tissues. Both cirrhosis and HCV contributed to the induction of Netrin-1 expression, whereas anti-HCV treatment resulted in a reduction of Netrin-1 expression. In vitro, HCV increased the level and translation of Netrin-1 in a NS5A-La-related protein 1 (LARP1-dependent fashion. Knockdown and forced expression experiments identified the receptor uncoordinated receptor-5 (UNC5A as an antagonist of the Netrin-1 signal, though it did not affect the death of HCV-infected cells. Netrin-1 enhanced infectivity of HCV particles and promoted viral entry by increasing the activation and decreasing the recycling of the epidermal growth factor receptor (EGFR, a protein that is dysregulated in HCC. Netrin-1 and HCV are, therefore, reciprocal inducers in vitro and in patients, as seen from the increase in viral morphogenesis and viral entry, both phenomena converging toward an increase in the level of infectivity of HCV virions. This functional association involving a cancer-related virus and Netrin-1 argues for evaluating the implication of UNC5 receptor ligands in other oncogenic microbial species.

  6. Transient downregulation of glomerular atrial natriuretic factor receptors in high output heart failure in the rat.

    Science.gov (United States)

    Gauquelin, G; Bonhomme, M C; Garcia, R

    1995-03-01

    The renal response to exogenous atrial natriuretic factor (ANF) is blunted in chronic heart failure. The aim of the present studies was to investigate whether renal ANF receptor regulation in chronic heart failure is a time related event. Glomerular ANF receptors were analysed in radioligand binding experiments at 0, 1, 2, 6, 12, 24, and 48 h, as well as at 1, 2, 4, and 8 weeks after the induction of an aortocaval shunt. Rats with aortocaval shunts had lower packed cell volume and body weight and higher relative heart weight than sham operated controls. Plasma ANF C and N terminal levels were increased in shunt rats as early as 5 min after establishment of the shunt. Right and left atrial ANF concentrations were decreased and ventricular ANF concentration was increased in shunt rats at 6 and 12 h respectively. Competitive inhibition of 125I-ANF binding showed that at 6 h the density (Bmax) of glomerular ANF receptors was significantly lower than in the controls [518(SEM 10) v 759(12) fmol.mg-1 protein] without differences in their affinity (Kd). The low Bmax in shunt animals persisted at 12, 24, and 48 h, even at 1 week [Bmax: 400(29) and 713(28) fmol.mg-1 protein; Kd: 80(2) and 70(4) pM, for AC rats and controls, respectively]. Bmax values were not significantly different at 2, 4, and 8 weeks. In 24 h animals, C-ANF displaced 65% of total binding, with both total and C ANF binding sites being 38% lower in shunt animals. Downregulation of glomerular ANF receptors is a transient event during the development of high output heart failure in the rat. Thus the blunted renal response to ANF during chronic heart failure is not likely to be due to a decrease in renal ANF receptor density or affinity.

  7. Potentiation of nerve growth factor-induced neurite outgrowth by fluvoxamine: role of sigma-1 receptors, IP3 receptors and cellular signaling pathways.

    Directory of Open Access Journals (Sweden)

    Tomoko Nishimura

    Full Text Available BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs have been widely used and are a major therapeutic advance in psychopharmacology. However, their pharmacology is quite heterogeneous. The SSRI fluvoxamine, with sigma-1 receptor agonism, is shown to potentiate nerve-growth factor (NGF-induced neurite outgrowth in PC 12 cells. However, the precise cellular and molecular mechanisms underlying potentiation by fluvoxamine are not fully understood. In this study, we examined the roles of cellular signaling pathways in the potentiation of NGF-induced neurite outgrowth by fluvoxamine and sigma-1 receptor agonists. METHODS AND FINDINGS: The effects of three SSRIs (fluvoxamine, sertraline, paroxetine and three sigma-1 receptor agonists (SA4503, 4-phenyl-1-(4-phenylbutyl piperidine (PPBP, and dehydroepiandrosterone (DHEA-sulfate on NGF-induced neurite outgrowth in PC12 cells were examined. Also examined were the effects of the sigma-1 receptor antagonist NE-100, inositol 1,4,5-triphosphate (IP(3 receptor antagonist, and specific inhibitors of signaling pathways in the potentiation of NGF-induced neurite outgrowth by selective sigma-1 receptor agonist SA4503. Fluvoxamine (but not sertraline or paroxetine and the sigma-1 receptor agonists SA4503, PPBP, and DHEA-sulfate significantly potentiated NGF-induced neurite outgrowth in PC12 cells in a concentration-dependent manner. The potentiation by fluvoxamine and the three sigma-1 receptor agonists was blocked by co-administration of the selective sigma-1 receptor antagonist NE-100, suggesting that sigma-1 receptors play a role in blocking the enhancement of NGF-induced neurite outgrowth. Moreover, the potentiation by SA4503 was blocked by co-administration of the IP(3 receptor antagonist xestospongin C. In addition, the specific inhibitors of phospholipase C (PLC-gamma, phosphatidylinositol 3-kinase (PI3K, p38MAPK, c-Jun N-terminal kinase (JNK, and the Ras/Raf/mitogen-activated protein kinase (MAPK

  8. Immunomodulator CD200 promotes neurotrophic activity by interacting with and activating the fibroblast growth factor receptor

    DEFF Research Database (Denmark)

    Pankratova, Stanislava; Bjornsdottir, Halla; Christensen, Claus;

    2016-01-01

    in the suppression of microglia activation. We for the first time demonstrated that CD200 can interact with and transduce signaling through activation of the fibroblast growth factor receptor (FGFR), thereby inducing neuritogenesis and promoting neuronal survival in primary neurons. CD200-induced FGFR...... phosphorylation was abrogated by CD200R, whereas FGF2-induced FGFR activation was inhibited by CD200. We also identified a sequence motif located in the first Ig-like module of CD200, likely representing the minimal CD200 binding site for FGFR. The FGFR binding motif overlaps with the CD200R binding site......, suggesting that they can compete for CD200 binding in cells that express both receptors. We propose that CD200 in neurons functions as a ligand of FGFR....

  9. Implication of platelet-derived growth factor receptor alpha in prostate cancer skeletal metastasis

    Institute of Scientific and Technical Information of China (English)

    Qingxin Liu; Danielle Jernigan; Yun Zhang; Alessandro Fatatis

    2011-01-01

    Metastasis represents by far the most feared complication of prostate carcinoma and is the main cause of death for patients.The skeleton is frequently targeted by disseminated cancer cells andrepresents the sole site of spread in more than 80% of prostate cancer cases.Compatibility between select malignant phenotypes and the microenvironment of colonized tissues is broadly recognized as the culprit for the organ-tropism of cancer cells.Here,we review our recent studies showing that the expression of platelet-derived growth factor receptor alpha (PDGFRα) supports the survival and growth of prostate cancer cells in the skeleton and that the soluble fraction of bone marrow activates PDGFRα in a ligand-independent fashion.Finally,we offer pre-clinical evidence that this receptor is a viable target for therapy.

  10. Ramucirumab (IMC-1121B): Monoclonal antibody inhibition of vascular endothelial growth factor receptor-2.

    Science.gov (United States)

    Spratlin, Jennifer

    2011-04-01

    Angiogenesis, a well-recognized characteristic of malignancy, has been exploited more than any other pathway targeted by biologic anti-neoplastic therapies. Vascular endothelial growth factor receptor-2 (VEGFR-2) is the critical receptor involved in malignant angiogenesis with its activation inducing a number of other cellular modifications resulting in tumor growth and metastases. Ramucirumab (IMC-1121B; ImClone Systems Corporation, Branchburg, NJ) is a fully human monoclonal antibody developed to specifically inhibit VEGFR-2. Ramucirumab is currently being investigated in multiple clinical trials across a variety of tumor types. Herein, angiogenesis inhibition in cancer is reviewed and up-to-date information on the clinical development of ramucirumab is presented.

  11. Treatment related changes of the serum epidermal growth factor receptor in advanced colorectal cancer

    DEFF Research Database (Denmark)

    Spindler, K G; Aalund Olsen, Dorte; Brandslund, I

    2009-01-01

    .001), and a correlation between the magnitude of increase and a higher degree of skin toxicity, a well known indicator of clinical benefit to EGFR inhibitors. sEGFR in rectal cancer patients displayed a decreasing tendency during CRT (p...e22096 Background: The epidermal growth factor receptor (EGFR) is an established target for therapy in colorectal cancer. The extracellular domain of the receptor is shed into circulation and detectable by ELISA. We investigated the changes in sEGFR levels during preoperative chemoradiation (CRT......) in rectal cancer patients and third-line treatment with cetuximab and irinotecan (CETIRI) in advanced disease, to elucidate the predictive or prognostic value in these settings. METHODS: We included 126 healthy controls and 118 patients with chemorefractory mCRC treated with cetuximab (initial 400/m(2) mg...

  12. Fibroblast growth factor receptor 2 plays an essential role in telencephalic progenitors.

    Science.gov (United States)

    Ever, Leah; Zhao, Rui-Jing; Eswarakumar, Veraragavan P; Gaiano, Nicholas

    2008-01-01

    We used loss-of-function analysis to determine the role of fibroblast growth factor receptor 2 (FGFR2) in telencephalic progenitors, and also to examine interactions between FGFR and Notch signaling. While the telencephalon of FGFR2 mutants appears grossly normal, mutant telencephalic progenitors exhibit altered proliferative behavior in vivo and in vitro. Based upon our prior finding that Notch1 activation increased neurosphere frequency in FGF2, we tested whether this effect is mediated by FGFR1 or FGFR2. We found that Notch1 activation increased neurosphere frequency in cells mutant for either FGFR1 or FGFR2, but had no effect on the reduced size of neurospheres mutant for those receptors. Additional analyses revealed biochemical changes in the adult neocortex mutant for the IIIc isoform of FGFR2, and essential roles for FGFR2 in nasopharynx, eyelid, and cornea development.

  13. Structural Basis for Negative Cooperativity in Growth Factor Binding to an EGF Receptor

    Energy Technology Data Exchange (ETDEWEB)

    Alvarado, Diego; Klein, Daryl E.; Lemmon, Mark A. (UPENN-MED)

    2010-09-27

    Transmembrane signaling by the epidermal growth factor receptor (EGFR) involves ligand-induced dimerization and allosteric regulation of the intracellular tyrosine kinase domain. Crystallographic studies have shown how ligand binding induces dimerization of the EGFR extracellular region but cannot explain the high-affinity and low-affinity classes of cell-surface EGF-binding sites inferred from curved Scatchard plots. From a series of crystal structures of the Drosophila EGFR extracellular region, we show here how Scatchard plot curvature arises from negatively cooperative ligand binding. The first ligand-binding event induces formation of an asymmetric dimer with only one bound ligand. The unoccupied site in this dimer is structurally restrained, leading to reduced affinity for binding of the second ligand, and thus negative cooperativity. Our results explain the cell-surface binding characteristics of EGF receptors and suggest how individual EGFR ligands might stabilize distinct dimeric species with different signaling properties.

  14. A Premature Termination of Human Epidermal Growth Factor Receptor Transcription in Escherichia coli

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    Jihene Elloumi-Mseddi

    2014-01-01

    Full Text Available Our success in producing an active epidermal growth factor receptor (EGFR tyrosine kinase in Escherichia coli encouraged us to express the full-length receptor in the same host. Despite its large size, we were successful at producing the full-length EGFR protein fused to glutathione S-transferase (GST that was detected by Western blot analysis. Moreover, we obtained a majoritarian truncated GST-EGFR form detectable by gel electrophoresis and Western blot. This truncated protein was purified and confirmed by MALDI-TOF/TOF analysis to belong to the N-terminal extracellular region of the EGFR fused to GST. Northern blot analysis showed two transcripts suggesting the occurrence of a transcriptional arrest.

  15. Expression of growth factor ligand and receptor genes in the preimplantation bovine embryo.

    Science.gov (United States)

    Watson, A J; Hogan, A; Hahnel, A; Wiemer, K E; Schultz, G A

    1992-02-01

    The sensitive technique of mRNA phenotyping with the reverse transcription-polymerase chain reaction was employed to determine the patterns of gene expression for several growth factor ligand and receptor genes during bovine preimplantation development. Several thousand bovine embryos encompassing a developmental series from one-cell zygotes to hatched blastocysts were produced by the application of in vitro maturation, fertilization, and oviductal epithelial cell embryo coculture methods. Transcripts for transforming growth factor (TGF-alpha) and platelet-derived growth factor (PDGF-A) are detectable in all preimplantation bovine stages as observed in the mouse. Transcripts for TGF-beta 2 and insulin-like growth factor (IGF-II) and the receptors for PDGF-alpha, insulin, IGF-I, and IGF-II are also detectable throughout bovine preimplantation development, suggesting that these mRNAs are products of both the maternal and the embryonic genomes in the cow, whereas in the mouse they are present only following the activation of the embryonic genome at the two-cell stage. In contrast to the mouse embryo, IGF-I mRNA was detected within preimplantation bovine embryos. Basic fibroblast growth factor (bFGF) is a maternal message in the bovine embryo, since it is only detectable up until the eight-cell embryo stage. Bovine trophoblast protein (bTP) mRNA was detectable within day 8 bovine blastocysts. As was observed in the mouse, the transcripts for insulin, epidermal growth factor (EGF), or nerve growth factor (NGF) were not detectable in any bovine embryo stage. Analyses of this type should aid the development of a completely defined culture medium for the more efficient production of preimplantation bovine embryos.

  16. Featured Article: Nuclear export of opioid growth factor receptor is CRM1 dependent.

    Science.gov (United States)

    Kren, Nancy P; Zagon, Ian S; McLaughlin, Patricia J

    2016-02-01

    Opioid growth factor receptor (OGFr) facilitates growth inhibition in the presence of its specific ligand opioid growth factor (OGF), chemically termed [Met(5)]-enkephalin. The function of the OGF-OGFr axis requires the receptor to translocate to the nucleus. However, the mechanism of nuclear export of OGFr is unknown. In this study, endogenous OGFr, as well as exogenously expressed OGFr-EGFP, demonstrated significant nuclear accumulation in response to leptomycin B (LMB), an inhibitor of CRM1-dependent nuclear export, suggesting that OGFr is exported in a CRM1-dependent manner. One consensus sequence for a nuclear export signal (NES) was identified. Mutation of the associated leucines, L217 L220 L223 and L225, to alanine resulted in decreased nuclear accumulation. NES-EGFP responded to LMB, indicating that this sequence is capable of functioning as an export signal in isolation. To determine why the sequence functions differently in isolation than as a full length protein, the localization of subNES was evaluated in the presence and absence of MG132, a potent inhibitor of proteosomal degradation. MG132 had no effect of subNES localization. The role of tandem repeats located at the C-terminus of OGFr was examined for their role in nuclear trafficking. Six of seven tandem repeats were removed to form deltaTR. DeltaTR localized exclusively to the nucleus indicating that the tandem repeats may contribute to the localization of the receptor. Similar to the loss of cellular proliferation activity (i.e. inhibition) recorded with subNES, deltaTR also demonstrated a significant loss of inhibitory activity indicating that the repeats may be integral to receptor function. These experiments reveal that OGFr contains one functional NES, L217 L220 L223 and L225 and can be exported from the nucleus in a CRM1-dependent manner.

  17. Decreased expression of fibroblast and keratinocyte growth factor isoforms and receptors during scarless repair.

    Science.gov (United States)

    Dang, Catherine M; Beanes, Steven R; Soo, Chia; Ting, Kang; Benhaim, Prosper; Hedrick, Marc H; Lorenz, H Peter

    2003-05-01

    Fibroblast growth factors (FGFs) are a family of 21 cytokines with a broad spectrum of activities, including regulation of cell proliferation, differentiation, and migration. The various FGFs bind to one or more of four different tyrosine kinase receptor types. FGFs 1, 2, 5, 7, and 10 are up-regulated during adult cutaneous wound healing. However, the expression of FGFs during fetal skin development and scarless wound healing has not been characterized. It was hypothesized that differential expression of FGF isoforms and receptors occurs during fetal skin development and that this differential expression pattern may regulate the transition from scarless repair to healing with scar formation. Excisional wounds (2 mm) were created on fetal rats at gestational days 16.5 (scarless) (one wound per fetus, n = 36 fetuses) and 19.5 (scarring) (one wound per fetus, n = 36 fetuses). Wounds were harvested at 24, 48, and 72 hours. Survival until wound harvest ranged from 66 to 75 percent for the gestational day 16 fetuses, and from 83 to 92 percent for the gestational day 19 fetuses. Nonwounded fetal skin from littermates (n = 12 fetuses per wound harvest time point) was used as the control. Wounds/skins were pooled by harvest time point, and RNA was isolated from pooled wounds/skins. Reduced-cycle, specific-primer reverse transcriptase-polymerase chain reaction was performed to determine the expression of FGF isoforms 2, 5, 7, 9, and 10 and FGF receptors 1, 2, and 4 in wounds relative to unwounded skin.In unwounded fetal skin, FGF isoform 5 expression more than doubled at birth. FGF 10 expression doubled during the transition period. FGF 7 expression increased more than sevenfold at birth. Expression of FGF isoforms 2 and 9 did not change during late fetal skin development. The expression of FGF receptors 1, 2, and 4 increased at birth. After wounding, expression of FGF isoforms 7 and 10 was down-regulated in scarless wounds, whereas FGF receptor 2 expression decreased in

  18. Serum TNF-α, sTNFR1, IL-6, IL-8 and IL-10 levels in hemorrhagic fever with renal syndrome.

    Science.gov (United States)

    Kyriakidis, Ioannis; Papa, Anna

    2013-07-01

    It is generally accepted that the pathogenesis of hantavirus infections is the result of virus-mediated host immune response. Hantaviruses, and mainly Dobrava-Belgrade virus, are present in Greece, and cause to humans hemorrhagic fever with renal syndrome (HFRS). Serum IL-6, IL-8, IL-10, TNF-α and sTNFR1 levels were measured in 29 HFRS Greek patients. Significant higher sTNFR1, IL-6, IL-8 and IL-10 levels were observed in severe than in mild/moderate cases, while TNF-α did not seem to be associated with disease severity. Correlations between cytokine levels and their fluctuation over time after onset of the illness, along with comparisons from previously published data on the field, led in building an immune response pattern for HFRS.

  19. Mammary tumors that become independent of the type I insulin-like growth factor receptor express elevated levels of platelet-derived growth factor receptors

    Directory of Open Access Journals (Sweden)

    Campbell Craig I

    2011-11-01

    Full Text Available Abstract Background Targeted therapies are becoming an essential part of breast cancer treatment and agents targeting the type I insulin-like growth factor receptor (IGF-IR are currently being investigated in clinical trials. One of the limitations of targeted therapies is the development of resistant variants and these variants typically present with unique gene expression patterns and characteristics compared to the original tumor. Results MTB-IGFIR transgenic mice, with inducible overexpression of the IGF-IR were used to model mammary tumors that develop resistance to IGF-IR targeting agents. IGF-IR independent mammary tumors, previously shown to possess characteristics associated with EMT, were found to express elevated levels of PDGFRα and PDGFRβ. Furthermore, these receptors were shown to be inversely expressed with the IGF-IR in this model. Using cell lines derived from IGF-IR-independent mammary tumors (from MTB-IGFIR mice, it was demonstrated that PDGFRα and to a lesser extent PDGFRβ was important for cell migration and invasion as RNAi knockdown of PDGFRα alone or PDGFRα and PDGFRβ in combination, significantly decreased tumor cell migration in Boyden chamber assays and suppressed cell migration in scratch wound assays. Somewhat surprisingly, concomitant knockdown of PDGFRα and PDGFRβ resulted in a modest increase in cell proliferation and a decrease in apoptosis. Conclusion During IGF-IR independence, PDGFRs are upregulated and function to enhance tumor cell motility. These results demonstrate a novel interaction between the IGF-IR and PDGFRs and highlight an important, therapeutically relevant pathway, for tumor cell migration and invasion.

  20. Integration of estrogen and progesterone receptors with pathological and molecular prognostic factors in breast cancer patients.

    Science.gov (United States)

    Gago, F E; Tello, O M; Diblasi, A M; Ciocca, D R

    1998-12-01

    In this study we have examined biopsies from women with localized primary breast cancer to investigate the prognostic performance of estrogen receptors (ER) and progesterone receptors (PR) for estimating the metastatic probability of the patients, and to explore whether discrimination gets better by combining clinicopathological and other molecular parameters into a score. This prospective study involved 205 patients with a median follow-up of 5 y. Among the evaluated clinicopathological data were: patient's age; tumor size; axillary lymph node involvement; and tumor grade. The most representative tumor samples were derived to a single laboratory for immunohistochemical evaluation of the following molecular markers: ER, PR, proliferating cell nuclear antigen (PCNA), p53 protein product, erbB-2 (HER-2/neu) oncoprotein, and P170 glycoprotein (mdrl gen product). Distant metastases (study endpoint) appeared in 19.5% (40/205) of the patients, most of these patients presented a mixture of poor, regular and good prognostic factors. Disease-free survival analysis procedures (Kaplan-Meier method) identified tumor size, axillary lymph node involvement, tumor grade, receptor status, PCNA, p53, erbB-2 and P170 as useful prognostic factors. Proportional hazard regression analysis (Cox) identified in order of importance erbB-2, tumor size, receptors status, tumor grade and PCNA as useful prognostic factors. To facilitate the evaluation of the prognostic factors, a practical and simple score system was derived. A high pathological score identified 65% of the patients that developed distant metastases, while a high molecular score was obtained in 57% of patients with metastatic disease. There was a significant improvement in the diagnosis of probability of being with distant metastases when the pathological score was combined with the molecular score, 82% of the patients with distant metastases showed an elevated combined score. Validation of this scoring system will need further

  1. Nuclear Factor-κB: Activation and Regulation during Toll-like Receptor Signaling

    Institute of Scientific and Technical Information of China (English)

    Ruaidhrí J. Carmody; Youhai H. Chen

    2007-01-01

    Toll-like receptors (TLRs) recognize distinct microbial components to initiate the innate and adaptive immune responses. TLR activation culminates in the expression of appropriate pro-inflammatory and immunomodulatory factors to meet pathogenic challenges. The transcription factor NF-κB is the master regulator of all TLR-induced responses and its activation is the pivotal event in TLR-mediated activation of the innate immune response. Many of the key molecular events required for TLR-induced NF-κB activation have been elucidated. However, much remain to be learned about the ability of TLRs to generate pathogen-specific responses using a limited number of transcription factors. This review will focus on our current understanding of NF-κB activation by TLRs and potential mechanisms for achieving a signal-specific response through NF-κB.

  2. Treatment of pancreatic cancer with epidermal growth factor receptor-targeted therapy

    Directory of Open Access Journals (Sweden)

    Bryan A Faller

    2009-09-01

    Full Text Available Bryan A Faller, Barbara BurtnessDepartment of Medical Oncology, Fox Chase Cancer Center, Philadelphia, PA, USAAbstract: Pancreatic adenocarcinoma is a common malignancy that remains refractory to available therapies. Gemcitabine has long been the standard, first-line agent in advanced disease. The epidermal growth factor receptor (EGFR is a commonly expressed target in pancreatic cancer that is involved in tumor proliferation, metastasis, and induction of angiogenesis. The addition of the EGFR inhibitor erlotinib to gemcitabine has recently been demonstrated to provide a small, yet statistically significant, survival benefit in advanced disease. This has prompted further research into the applications of EGFR-targeted therapy in pancreatic cancer, albeit with disappointing results. Resistance to these therapies seems highly prevalent and has been implicated in their limited efficacy. The development of rash is associated with treatment efficacy and suggests that predictive factors may one day be identified to guide appropriate patient selection for these agents. Preclinical research has shown promise that resistance to EGFR-targeted therapies can be overcome through a variety of approaches. Application of this research in clinical trials may ultimately yield an unquestioned role for EGFR-targeted therapy in the management of this disease.Keywords: cetuximab, drug resistance, epidermal growth factor receptor, erlotinib, gemcitabine, pancreatic cancer

  3. Brain-derived neurotrophic factor and its receptors in Bergmann glia cells.

    Science.gov (United States)

    Poblete-Naredo, Irais; Guillem, Alain M; Juárez, Claudia; Zepeda, Rossana C; Ramírez, Leticia; Caba, Mario; Hernández-Kelly, Luisa C; Aguilera, José; López-Bayghen, Esther; Ortega, Arturo

    2011-12-01

    Brain-derived neurotrophic factor is an abundant and widely distributed neurotrophin expressed in the Central Nervous System. It is critically involved in neuronal differentiation and survival. The expression of brain-derived neurotrophic factor and that of its catalytic active cognate receptor (TrkB) has been extensively studied in neuronal cells but their expression and function in glial cells is still controversial. Despite of this fact, brain-derived neurotrophic factor is released from astrocytes upon glutamate stimulation. A suitable model to study glia/neuronal interactions, in the context of glutamatergic synapses, is the well-characterized culture of chick cerebellar Bergmann glia cells. Using, this system, we show here that BDNF and its functional receptor are present in Bergmann glia and that BDNF stimulation is linked to the activation of the phosphatidyl-inositol 3 kinase/protein kinase C/mitogen-activated protein kinase/Activator Protein-1 signaling pathway. Accordingly, reverse transcription-polymerase chain reaction (RT-PCR) experiments predicted the expression of full-length and truncated TrkB isoforms. Our results suggest that Bergmann glia cells are able to express and respond to BDNF stimulation favoring the notion of their pivotal role in neuroprotection. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. The aryl hydrocarbon receptor and estrogen receptor alpha differentially modulate nuclear factor erythroid-2-related factor 2 transactivation in MCF-7 breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Raymond; Matthews, Jason, E-mail: jason.matthews@utoronto.ca

    2013-07-15

    Nuclear factor erythroid-2-related factor 2 (NRF2; NFE2L2) plays an important role in mediating cellular protection against reactive oxygen species. NRF2 signaling is positively modulated by the aryl hydrocarbon receptor (AHR) but inhibited by estrogen receptor alpha (ERα). In this study we investigated the crosstalk among NRF2, AHR and ERα in MCF-7 breast cancer cells treated with the NRF2 activator sulforaphane (SFN), a dual AHR and ERα activator, 3,3′-diindolylmethane (DIM), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or 17β-estradiol (E2). SFN-dependent increases in NADPH-dependent oxidoreductase 1 (NQO1) and heme oxygenase I (HMOX1) mRNA levels were significantly reduced after co-treatment with E2. E2-dependent repression of NQO1 and HMOX1 was associated with increased ERα but reduced p300 recruitment and reduced histone H3 acetylation at both genes. In contrast, DIM + SFN or TCDD + SFN induced NQO1 and HMOX1 mRNA expression to levels higher than SFN alone, which was prevented by RNAi-mediated knockdown of AHR. DIM + SFN but not TCDD + SFN also induced recruitment of ERα to NQO1 and HMOX1. However, the presence of AHR at NQO1 and HMOX1 restored p300 recruitment and histone H3 acetylation, thereby reversing the ERα-dependent repression of NRF2. Taken together, our study provides further evidence of functional interplay among NRF2, AHR and ERα signaling pathways through altered p300 recruitment to NRF2-regulated target genes. - Highlights: • We examined crosstalk among ERα, AHR, and NRF2 in MCF-7 breast cancer cells. • AHR enhanced the mRNA expression levels of two NRF2 target genes – HMOX1 and NQO1. • ERα repressed HMOX1 and NQO1 expression via decreased histone acetylation. • AHR prevented ERα-dependent repression of HMOX1 and NQO1.

  5. Neuritogenic and neuroprotective properties of peptide agonists of the fibroblast growth factor receptor

    DEFF Research Database (Denmark)

    Li, Shizhong; Bock, Elisabeth Marianne; Berezin, Vladimir

    2010-01-01

    Fibroblast growth factor receptors (FGFRs) interact with their cognate ligands, FGFs, and with a number of cell adhesion molecules (CAMs), such as the neural cell adhesion molecule (NCAM), mediating a wide range of events during the development and maintenance of the nervous system. Determination...... of protein structure, in silico modeling and biological studies have recently resulted in the identification of FGFR binding peptides derived from various FGFs and NCAM mimicking the effects of these molecules with regard to their neuritogenic and neuroprotective properties. This review focuses on recently...... developed functional peptide agonists of FGFR with possible therapeutic potential....

  6. Neuritogenic and Neuroprotective Properties of Peptide Agonists of the Fibroblast Growth Factor Receptor

    Directory of Open Access Journals (Sweden)

    Shizhong Li

    2010-05-01

    Full Text Available Fibroblast growth factor receptors (FGFRs interact with their cognate ligands, FGFs, and with a number of cell adhesion molecules (CAMs, such as the neural cell adhesion molecule (NCAM, mediating a wide range of events during the development and maintenance of the nervous system. Determination of protein structure, in silico modeling and biological studies have recently resulted in the identification of FGFR binding peptides derived from various FGFs and NCAM mimicking the effects of these molecules with regard to their neuritogenic and neuroprotective properties. This review focuses on recently developed functional peptide agonists of FGFR with possible therapeutic potential.

  7. Expression and functional characterization of platelet-derived growth factor receptor-like gene

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM:To investigate the role of platelet-derived growth factor receptor-like gene(PDGFRL)in the anti-cancer therapy for colorectal cancers(CRC).METHODS:PDGFRL mRNA and protein levels were measured by reverse transcription-polymerase chain reaction(RT-PCR)and immunohistochemistry in CRC and colorectal normal tissues.PDGFRL prokaryotic expression vector was carried out in Escherichia coli(E.coli),and purified by immobilized metal affinity chromatography.The effect of PDGFRL protein on CRC HCT-116 cells was det...

  8. Epidermal Growth Factor Receptor Overexpression as a Target for Auger Electron Radiotherapy of Breast Cancer

    Science.gov (United States)

    2002-08-01

    radiotherapeutic agent for breast cancer. © 2001 Elsevier Science Inc . All rights reserved. Keywords: Breast cancer; Indium-111; Epidermal growth factor receptor... Science Inc . All rights reserved. PII: S0969-8051(01)00262-1 896 .1. Wang et al. / Nuclear Medicine and Biology 28 (2001) 895-902 A NW3 rn- NH, + NHC...raymond.reilly@utoronto.ca (R.M. Reilly). (cDTPAA) with an E-amino group on a lysine residue or the 0969-8051/01/$ - see front matter © 2001 Elsevier

  9. Regulation of tumour necrosis factor (TNF) induced apoptosis by soluble TNF receptors in Helicobacter pylori infection

    OpenAIRE

    Shibata, J; Goto, H.; Arisawa, T.; Niwa, Y.; Hayakawa, T.; Nakayama, A.; Mori, N.

    1999-01-01

    BACKGROUND—Tumour necrosis factor (TNF) is a predominant cytokine produced in the gastric mucosa of patients with Helicobacter pylori infection. TNF induces apoptosis in a variety of cells. The soluble TNF receptors (sTNF-Rs) can be divided into sTNF-RI and sTNF-RII, both of which inhibit TNF activity. However, their precise mechanisms remain unclear.
AIM—To investigate the role of sTNF-Rs in H pylori infection.
METHODS—In 40 patients, production of TNF and sTNF-Rs in gastric mucosa was measu...

  10. Fibroblast growth factor (FGF)-21 signals through both FGF receptor-1 and 2

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Fibroblast growth factor (FGF)-21 is a member of the FGF superfamily based on sequence homology. However, unlike most members of this family it does not show any mitogenic activity in all cell types tested. The objective of this study is to identify and characterize receptors for this molecule. Sequencing of the cDNA clones from 3T3-L1 adipocytes indicates that the only isoforms for FGFR-1 and 2 expressed in 3T3-L1 cells are 1IIIc and 2IIIc, respectively, suggesting that FGF-21 regulates glucose metabolism in 3T3-L1 adipocytes through FGFR-1IIIc and FGFR-2IIIc.

  11. Identification of soluble forms of the fibroblast growth factor receptor in blood.

    OpenAIRE

    Hanneken, A; Ying, W; Ling, N; Baird, A.

    1994-01-01

    We have purified three acidic (FGF-1) and basic (FGF-2) fibroblast growth factor binding proteins (FGF-BP1, FGF-BP2, and FGF-BP3) from human plasma and calf serum and demonstrate the presence of these circulating FGF-BPs in blood. Each are truncated forms of the high-affinity FGF receptor (FGFR-1). FGF-BP1 and FGF-BP2 have estimated molecular masses of 70-85 kDa and 55-60 kDa, respectively, and are detected by using 125I-labeled FGF-2 ligand blotting. Immunoblotting with four distinct antibod...

  12. Insulin-like growth factor-I receptor in proliferation and motility of pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Minoru; Tomizawa; Fuminobu; Shinozaki; Takao; Sugiyama; Shigenori; Yamamoto; Makoto; Sueishi; Takanobu; Yoshida

    2010-01-01

    AIM:To develop a molecular therapy for pancreatic cancer, the insulin-like growth factor-I (IGF-I) signaling pathway was analyzed.METHODS: Pancreatic cancer cell lines (MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4) were cultured in media with 10 mL/L fetal bovine serum. Western blotting analysis was performed to clarify the expression of IGF-I receptor (IGF-IR). Picropodophyllin (PPP), a specific inhibitor of IGF-IR, LY294002, a specific inhibitor of phosphatidylinositol3 kinase (PI3K), and PD980...

  13. Hepatitis C virus induced endothelial inflammatory response depends on the functional expression of TNFα receptor subtype 2.

    Directory of Open Access Journals (Sweden)

    Joachim Pircher

    Full Text Available In hepatitis C virus (HCV infection, morbidity and mortality often result from extrahepatic disease manifestations. We provide evidence for a role of receptors of the innate immune system in virally induced inflammation of the endothelium in vitro and in vivo. Corresponding to the in vitro finding of an HCV-dependent induction of proinflammatory mediators in endothelial cells, mice treated with poly (I:C exhibit a significant reduction in leukocyte rolling velocity, an increase in leukocyte adhesion to the vessel wall and an increased extravasation of leukocytes. HCV directly promotes activation, adhesion and infiltration of inflammatory cells into the vessel wall by activation of endothelial viral receptors. Poly (I:C induces the expression of TLR3 in vivo and hereby allows for amplification of all of the aforementioned responses upon viral infection. Proinflammatory effects of viral RNA are specifically mediated by TLR3 and significantly enhanced by tumor necrosis factor alpha (TNFα. HCV-RNA induces the endothelial expression of TNFα and TNFα receptor subtype 2 and we provide evidence that leucocyte adhesion and transmigration in response to activation of viral RNA receptors seem to depend on expression of functional TNFR2. Our results demonstrate that endothelial cells actively participate in immune mediated vascular inflammation caused by viral infections.

  14. The cytokines cardiotrophin-like cytokine/cytokine-like factor-1 (CLC/CLF) and ciliary neurotrophic factor (CNTF) differ in their receptor specificities.

    Science.gov (United States)

    Tormo, Aurélie Jeanne; Letellier, Marie-Claude; Lissilaa, Rami; Batraville, Laurie-Anne; Sharma, Mukut; Ferlin, Walter; Elson, Greg; Crabé, Sandrine; Gauchat, Jean-François

    2012-12-01

    Ciliary neurotrophic factor (CNTF) and cardiotrophin-like cytokine (CLC) are two cytokines with neurotrophic and immunomodulatory activities. CNTF is a cytoplasmic factor believed to be released upon cellular damage, while CLC requires interaction with a soluble cytokine receptor, cytokine-like factor 1 (CLF), to be efficiently secreted. Both cytokines activate a receptor complex comprising the cytokine binding CNTF receptor α (CNTFRα) and two signaling chains namely, leukemia inhibitory factor receptor β (LIFRβ) and gp130. Human CNTF can recruit and activate an alternative receptor in which CNTFRα is substituted by IL-6Rα. As both CNTF and CLC have immune-regulatory activities in mice, we compared their ability to recruit mouse receptors comprising both gp130 and LIFRβ signaling chains and either IL-6Rα or IL-11Rα which, unlike CNTFRα, are expressed by immune cells. Our results indicate that 1) mouse CNTF, like its human homologue, can activate cells expressing gp130/LIFRβ with either CNTFRα or IL-6Rα and, 2) CLC/CLF is more restricted in its specificity in that it activates only the tripartite CNTFR. Several gp130 signaling cytokines influence T helper cell differentiation. We therefore investigated the effect of CNTF on CD4 T cell cytokine production. We observed that CNTF increased the number of IFN-γ producing CD4 T cells. As IFN-γ is considered a mediator of the therapeutic effect of IFN-β in multiple sclerosis, induction of IFN-γ by CNTF may contribute to the beneficial immunomodulatory effect of CNTF in mouse multiple sclerosis models. Together, our results indicate that CNTF activates the same tripartite receptors in mouse and human cells and further validate rodent models for pre-clinical investigation of CNTF and CNTF derivatives. Furthermore, CNTF and CLC/CLF differ in their receptor specificities. The receptor α chain involved in the immunomodulatory effects of CLC/CLF remains to be identified.

  15. Nuclear functions and subcellular trafficking mechanisms of the epidermal growth factor receptor family

    Science.gov (United States)

    2012-01-01

    Accumulating evidence suggests that various diseases, including many types of cancer, result from alteration of subcellular protein localization and compartmentalization. Therefore, it is worthwhile to expand our knowledge in subcellular trafficking of proteins, such as epidermal growth factor receptor (EGFR) and ErbB-2 of the receptor tyrosine kinases, which are highly expressed and activated in human malignancies and frequently correlated with poor prognosis. The well-characterized trafficking of cell surface EGFR is routed, via endocytosis and endosomal sorting, to either the lysosomes for degradation or back to the plasma membrane for recycling. A novel nuclear mode of EGFR signaling pathway has been gradually deciphered in which EGFR is shuttled from the cell surface to the nucleus after endocytosis, and there, it acts as a transcriptional regulator, transmits signals, and is involved in multiple biological functions, including cell proliferation, tumor progression, DNA repair and replication, and chemo- and radio-resistance. Internalized EGFR can also be transported from the cell surface to several intracellular compartments, such as the Golgi apparatus, the endoplasmic reticulum, and the mitochondria, in addition to the nucleus. In this review, we will summarize the functions of nuclear EGFR family and the potential pathways by which EGFR is trafficked from the cell surface to a variety of cellular organelles. A better understanding of the molecular mechanism of EGFR trafficking will shed light on both the receptor biology and potential therapeutic targets of anti-EGFR therapies for clinical application. PMID:22520625

  16. Stabilization of the bioactivity of tumor necrosis factor by its soluble receptors

    DEFF Research Database (Denmark)

    Aderka, D; Engelmann, H; Maor, Y;

    1992-01-01

    activity; at high concentrations, the sTNF-Rs indeed inhibit TNF effects. However, we report here that in the presence of low concentrations of the sTNF-Rs, effects of TNF whose induction depend on prolonged treatment with this cytokine are augmented, reflecting an attenuation by the sTNF-Rs of spontaneous......The receptors for tumor necrosis factor (TNF) exist in cell-associated as well as soluble forms, both binding specifically to TNF. Since the soluble forms of TNF receptors (sTNF-Rs) can compete with the cell-associated TNF receptors for TNF, it was suggested that they function as inhibitors of TNF...... TNF activity decay. Evidence that this stabilization of TNF activity by the sTNF-Rs follows from stabilization of TNF structure within the complexes that TNF forms with the sTNF-Rs is presented here, suggesting that the sTNF-Rs can affect TNF activity not only by interfering with its binding to cells...

  17. Orexin-corticotropin-releasing factor receptor heteromers in the ventral tegmental area as targets for cocaine.

    Science.gov (United States)

    Navarro, Gemma; Quiroz, César; Moreno-Delgado, David; Sierakowiak, Adam; McDowell, Kimberly; Moreno, Estefanía; Rea, William; Cai, Ning-Sheng; Aguinaga, David; Howell, Lesley A; Hausch, Felix; Cortés, Antonio; Mallol, Josefa; Casadó, Vicent; Lluís, Carme; Canela, Enric I; Ferré, Sergi; McCormick, Peter J

    2015-04-29

    Release of the neuropeptides corticotropin-releasing factor (CRF) and orexin-A in the ventral tegmental area (VTA) play an important role in stress-induced cocaine-seeking behavior. We provide evidence for pharmacologically significant interactions between CRF and orexin-A that depend on oligomerization of CRF1 receptor (CRF1R) and orexin OX1 receptors (OX1R). CRF1R-OX1R heteromers are the conduits of a negative crosstalk between orexin-A and CRF as demonstrated in transfected cells and rat VTA, in which they significantly modulate dendritic dopamine release. The cocaine target σ1 receptor (σ1R) also associates with the CRF1R-OX1R heteromer. Cocaine binding to the σ1R-CRF1R-OX1R complex promotes a long-term disruption of the orexin-A-CRF negative crosstalk. Through this mechanism, cocaine sensitizes VTA cells to the excitatory effects of both CRF and orexin-A, thus providing a mechanism by which stress induces cocaine seeking.

  18. Immunotoxin Therapies for the Treatment of Epidermal Growth Factor Receptor-Dependent Cancers

    Directory of Open Access Journals (Sweden)

    Nathan Simon

    2016-05-01

    Full Text Available Many epithelial cancers rely on enhanced expression of the epidermal growth factor receptor (EGFR to drive proliferation and survival pathways. Development of therapeutics to target EGFR signaling has been of high importance, and multiple examples have been approved for human use. However, many of the current small molecule or antibody-based therapeutics are of limited effectiveness due to the inevitable development of resistance and toxicity to normal tissues. Recombinant immunotoxins are therapeutic molecules consisting of an antibody or receptor ligand joined to a protein cytotoxin, combining the specific targeting of a cancer-expressed receptor with the potent cell killing of cytotoxic enzymes. Over the decades, many bacterial- or plant-based immunotoxins have been developed with the goal of targeting the broad range of cancers reliant upon EGFR overexpression. Many examples demonstrate excellent anti-cancer properties in preclinical development, and several EGFR-targeted immunotoxins have progressed to human trials. This review summarizes much of the past and current work in the development of immunotoxins for targeting EGFR-driven cancers.

  19. Nuclear functions and subcellular trafficking mechanisms of the epidermal growth factor receptor family

    Directory of Open Access Journals (Sweden)

    Wang Ying-Nai

    2012-04-01

    Full Text Available Abstract Accumulating evidence suggests that various diseases, including many types of cancer, result from alteration of subcellular protein localization and compartmentalization. Therefore, it is worthwhile to expand our knowledge in subcellular trafficking of proteins, such as epidermal growth factor receptor (EGFR and ErbB-2 of the receptor tyrosine kinases, which are highly expressed and activated in human malignancies and frequently correlated with poor prognosis. The well-characterized trafficking of cell surface EGFR is routed, via endocytosis and endosomal sorting, to either the lysosomes for degradation or back to the plasma membrane for recycling. A novel nuclear mode of EGFR signaling pathway has been gradually deciphered in which EGFR is shuttled from the cell surface to the nucleus after endocytosis, and there, it acts as a transcriptional regulator, transmits signals, and is involved in multiple biological functions, including cell proliferation, tumor progression, DNA repair and replication, and chemo- and radio-resistance. Internalized EGFR can also be transported from the cell surface to several intracellular compartments, such as the Golgi apparatus, the endoplasmic reticulum, and the mitochondria, in addition to the nucleus. In this review, we will summarize the functions of nuclear EGFR family and the potential pathways by which EGFR is trafficked from the cell surface to a variety of cellular organelles. A better understanding of the molecular mechanism of EGFR trafficking will shed light on both the receptor biology and potential therapeutic targets of anti-EGFR therapies for clinical application.

  20. Increased expression of receptors for orexigenic factors in nodose ganglion of diet-induced obese rats.

    Science.gov (United States)

    Paulino, Gabriel; Barbier de la Serre, Claire; Knotts, Trina A; Oort, Pieter J; Newman, John W; Adams, Sean H; Raybould, Helen E

    2009-04-01

    The vagal afferent pathway is important in short-term regulation of food intake, and decreased activation of this neural pathway with long-term ingestion of a high-fat diet may contribute to hyperphagic weight gain. We tested the hypothesis that expression of genes encoding receptors for orexigenic factors in vagal afferent neurons are increased by long-term ingestion of a high-fat diet, thus supporting orexigenic signals from the gut. Obesity-prone (DIO-P) rats fed a high-fat diet showed increased body weight and hyperleptinemia compared with low-fat diet-fed controls and high-fat diet-induced obesity-resistant (DIO-R) rats. Expression of the type I cannabinoid receptor and growth hormone secretagogue receptor 1a in the nodose ganglia was increased in DIO-P compared with low-fat diet-fed controls or DIO-R rats. Shifts in the balance between orexigenic and anorexigenic signals within the vagal afferent pathway may influence food intake and body weight gain induced by high fat diets.

  1. Radiotracer Methods for Targeted Imaging of the Epidermal Growth Factor Receptor

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kyung Ho; Lee, Kyung Han [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2008-06-15

    While indirect targeting strategies using reporter-genes are taking center stage in current molecular imaging research, another vital strategy has long involved direct imaging of specific receptors using radiolabeled ligands. Recently, there is renewal of immense interest in this area with particular attention to the epidermal growth factor receptor (EGFR), a transmembrane glycoprotein critically involved in the regulation of many cellular functions and malignancies. Recently, two novel classes of EGFR-targeting anticancer drugs have entered clinical trials with great expectations. These are monoclonal antibodies such as cetuximab that target the extracellular domain, and small molecule tyrosine kinase inhibitors such as gefitinib (Iressa) and erlotinib (Tarceva) that target the catalytic domain of the receptor. However, early results have showed disappointing survival benefits, disclosing a major challenge for this therapeutic strategy; namely, the need to identify tumors that are most likely to respond to the agents. To address this important clinical issue, several noninvasive imaging techniques are under investigation including radiolabeled probes based on small molecule tyrosine kinase inhibitors, anti-EGFR antibodies, and EGF peptides. This review describes the current status, limitations, and future prospects in the development of radiotracer methods for EGFR imaging.

  2. IDENTIFICATION OF NOVEL FIBROBLAST GROWTH FACTOR RECEPTOR 3 GENE MUTATIONS IN ACTINIC CHEILITIS

    Science.gov (United States)

    Chou, Annie; Dekker, Nusi; Jordan, Richard C.K.

    2009-01-01

    Objective Activating mutations in the fibroblast growth factor receptor 3 (FGFR3) gene are responsible for several craniosynostosis and chondrodysplasia syndromes as well as some human cancers including bladder and cervical carcinoma. Despite a high frequency in some benign skin disorders, FGFR3 mutations have not been reported in cutaneous malignancies. Actinic cheilitis (AC) is a sun-induced premalignancy affecting the lower lip that frequently progresses to squamous cell carcinoma (SCC). The objective of this study was to determine if FGFR3 gene mutations are present in AC and SCC of the lip. Study Design DNA was extracted and purified from micro-dissected, formalin-fixed, paraffin-embedded tissue sections of 20 cases of AC and SCC arising in AC. Exons 7, 15, and 17 were PCR amplified and direct sequenced. Results Four novel somatic mutations in the FGFR3 gene were identified: exon 7 mutation 742C→T (amino acid change R248C), exon 15 mutations 1850A→G (D617G) and 1888G→A (V630M), and exon 17 mutation 2056G→A (E686K). Grade of dysplasia did not correlate with presence of mutations. Conclusion The frequency of FGFR3 receptor mutations suggests a functional role for the FGFR3 receptor in the development of epithelial disorders and perhaps a change may contribute to the pathogenesis of some AC and SCC. PMID:19327639

  3. Neuropilin-1 mediates vascular permeability independently of vascular endothelial growth factor receptor-2 activation.

    Science.gov (United States)

    Roth, Lise; Prahst, Claudia; Ruckdeschel, Tina; Savant, Soniya; Weström, Simone; Fantin, Alessandro; Riedel, Maria; Héroult, Mélanie; Ruhrberg, Christiana; Augustin, Hellmut G

    2016-04-26

    Neuropilin-1 (NRP1) regulates developmental and pathological angiogenesis, arteriogenesis, and vascular permeability, acting as a coreceptor for semaphorin 3A (Sema3A) and the 165-amino acid isoform of vascular endothelial growth factor A (VEGF-A165). NRP1 is also the receptor for the CendR peptides, a class of cell- and tissue-penetrating peptides with a specific R-x-x-R carboxyl-terminal motif. Because the cytoplasmic domain of NRP1 lacks catalytic activity, NRP1 is mainly thought to act through the recruitment and binding to other receptors. We report here that the NRP1 intracellular domain mediates vascular permeability. Stimulation with VEGF-A165, a ligand-blocking antibody, and a CendR peptide led to NRP1 accumulation at cell-cell contacts in endothelial cell monolayers, increased cellular permeability in vitro and vascular leakage in vivo. Biochemical analyses, VEGF receptor-2 (VEGFR-2) silencing, and the use of a specific VEGFR blocker established that the effects induced by the CendR peptide and the antibody were independent of VEGFR-2. Moreover, leakage assays in mice expressing a mutant NRP1 lacking the cytoplasmic domain revealed that this domain was required for NRP1-induced vascular permeability in vivo. Hence, these data define a vascular permeability pathway mediated by NRP1 but independent of VEGFR-2 activation.

  4. Chronic neuron- and age-selective down-regulation of TNF receptor expression in triple-transgenic Alzheimer disease mice leads to significant modulation of amyloid- and Tau-related pathologies.

    Science.gov (United States)

    Montgomery, Sara L; Narrow, Wade C; Mastrangelo, Michael A; Olschowka, John A; O'Banion, M Kerry; Bowers, William J

    2013-06-01

    Neuroinflammation, through production of proinflammatory molecules and activated glial cells, is implicated in Alzheimer's disease (AD) pathogenesis. One such proinflammatory mediator is tumor necrosis factor α (TNF-α), a multifunctional cytokine produced in excess and associated with amyloid β-driven inflammation and cognitive decline. Long-term global inhibition of TNF receptor type I (TNF-RI) and TNF-RII signaling without cell or stage specificity in triple-transgenic AD mice exacerbates hallmark amyloid and neurofibrillary tangle pathology. These observations revealed that long-term pan anti-TNF-α inhibition accelerates disease, cautions against long-term use of anti-TNF-α therapeutics for AD, and urges more selective regulation of TNF signaling. We used adeno-associated virus vector-delivered siRNAs to selectively knock down neuronal TNF-R signaling. We demonstrate divergent roles for neuronal TNF-RI and TNF-RII where loss of opposing TNF-RII leads to TNF-RI-mediated exacerbation of amyloid β and Tau pathology in aged triple-transgenic AD mice. Dampening of TNF-RII or TNF-RI+RII leads to a stage-independent increase in Iba-1-positive microglial staining, implying that neuronal TNF-RII may act nonautonomously on the microglial cell population. These results reveal that TNF-R signaling is complex, and it is unlikely that all cells and both receptors will respond positively to broad anti-TNF-α treatments at various stages of disease. In aggregate, these data further support the development of cell-, stage-, and/or receptor-specific anti-TNF-α therapeutics for AD.

  5. Morphological and Hormonal Identiifcation of Porcine Atretic Follicles and Relationship Analysis of Hormone Receptor Levels During Granulosa Cell Apoptosis In vivo

    Institute of Scientific and Technical Information of China (English)

    YU De-bing; YU Min-li; LIN Fei; JIANG Bao-chun; YANG Li-na; WANG Si-yu; ZHAO Ying; WNAG Zheng-chao

    2014-01-01

    Recent reports have demonstrated that follicular atresia is initiated or caused by granulosa cell apoptosis followed by theca cell degeneration in mammalian ovaries, but the mechanism of follicular atresia is still to be elucidated. Therefore, our present study was designed to examine our hypothesis that the changes of follicular microenvironment induce the granulosa cell apoptosis during pocrine follicular atresia in vivo. We ifrstly isolated intact porcine antral follicles and identiifed them into three groups, healthy follicles (HF), early atretic follicles (EAF) and progressed atretic follicles (PAF) through morphology and histology. To further conifrm their status, we detected hormone levels in follicular lfuids and the expression level of apoptosis gene Bax in granulosa cells. The rate of progesterone (P) and estradiol (E2) was increased with the expression of Bax, indicating hormone can be used as a marker of granulosa cell apoptosis or follicular atresia. Finally, we analyzed the expression level of hormone receptor genes in granulosa cells and their relationship with follicular atresia. In PAF, the expression of Progesterone receptor (PGR) was increased signiifcantly while estradiol receptor (ER) had no notable changes, which suggesting the increased-PGR accelerated the effect of P-stimulated granulosa cell apoptosis. The dramatic increasing of androgen receptor (AR) expression in PAF and the obvious increase of tumor necrosis factor-αreceptor (TNFR) in EAF indicated that there are different pathways regulating granulosa cell apoptosis during follicular atresia. Together, our results suggested that different pathways of granulosa cell apoptosis was induced by changing the follicular microenvironment during follicular atresia.

  6. Fibroblast growth factor receptor 4 regulates tumor invasion by coupling fibroblast growth factor signaling to extracellular matrix degradation

    DEFF Research Database (Denmark)

    Sugiyama, Nami; Varjosalo, Markku; Meller, Pipsa;

    2010-01-01

    Aberrant expression and polymorphism of fibroblast growth factor receptor 4 (FGFR4) has been linked to tumor progression and anticancer drug resistance. We describe here a novel mechanism of tumor progression by matrix degradation involving epithelial-to-mesenchymal transition in response...... to membrane-type 1 matrix metalloproteinase (MT1-MMP, MMP-14) induction at the edge of tumors expressing the FGFR4-R388 risk variant. Both FGFR4 and MT1-MMP were upregulated in tissue biopsies from several human cancer types including breast adenocarcinomas, where they were partially coexpressed at the tumor....../stroma border and tumor invasion front. The strongest overall coexpression was found in prostate carcinoma. Studies with cultured prostate carcinoma cell lines showed that the FGFR4-R388 variant, which has previously been associated with poor cancer prognosis, increased MT1-MMP-dependent collagen invasion...

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

    Science.gov (United States)

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

    2016-05-01

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

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

    Science.gov (United States)

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

    2015-01-01

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

  9. Clopidogrel inhibits angiogenesis of gastric ulcer healing via downregulation of vascular endothelial growth factor receptor 2.

    Science.gov (United States)

    Luo, Jiing-Chyuan; Peng, Yen-Ling; Chen, Tseng-Shing; Huo, Teh-Ia; Hou, Ming-Chih; Huang, Hui-Chun; Lin, Han-Chieh; Lee, Fa-Yauh

    2016-09-01

    Although clopidogrel does not cause gastric mucosal injury, it does not prevent peptic ulcer recurrence in high-risk patients. We explored whether clopidogrel delays gastric ulcer healing via inhibiting angiogenesis and to elucidate the possible mechanisms. Gastric ulcers were induced in Sprague Dawley rats, and ulcer healing and angiogenesis of ulcer margin were compared between clopidogrel-treated rats and controls. The expressions of the proangiogenic growth factors and their receptors including basic fibroblast growth factor (bFGF), bFGF receptor (FGFR), vascular endothelial growth factor (VEGF), VEGFR1, VEGFR2, platelet-derived growth factor (PDGF)A, PDGFB, PDGFR A, PDGFR B, and phosphorylated form of mitogenic activated protein kinase pathways over the ulcer margin were compared via western blot and reverse transcription polymerase chain reaction. In vitro, human umbilical vein endothelial cells (HUVECs) were used to elucidate how clopidogrel inhibited growth factors-stimulated HUVEC proliferation. The ulcer sizes were significantly larger and the angiogenesis of ulcer margin was significantly diminished in the clopidogrel (2 and 10 mg/kg/d) treated groups. Ulcer induction markedly increased the expression of phosphorylated form of extracellular signal-regulated kinase (pERK), FGFR2, VEGF, VEGFR2, and PDGFRA when compared with those of normal mucosa. Clopidogrel treatment significantly decreased pERK, FGFR2, VEGF, VEGFR2, and PDGFRA expression at the ulcer margin when compared with those of the respective control group. In vitro, clopidogrel (10(-6)M) inhibited VEGF-stimulated (20 ng/mL) HUVEC proliferation, at least, via downregulation of VEGFR2 and pERK. Clopidogrel inhibits the angiogenesis of gastric ulcer healing at least partially by the inhibition of the VEGF-VEGFR2-ERK signal transduction pathway. Copyright © 2015. Published by Elsevier B.V.

  10. Divergent effects of insulin-like growth factor-1 receptor expression on prognosis of estrogen receptor positive versus triple negative invasive ductal breast carcinoma

    NARCIS (Netherlands)

    Hartog, H.; Horlings, H.M.; Vegt, B. van der; Kreike, B.; Ajouaou, A.; Vijver, M.J. van de; Marike Boezen, H.; Bock, G.H. de; Graaf, W.T. van der; Wesseling, J.

    2011-01-01

    The insulin-like growth factor type 1 receptor (IGF1R) is involved in progression of breast cancer and resistance to systemic treatment. Targeting IGF1R signaling may, therefore, be beneficial in systemic treatment. We report the effect of IGF1R expression on prognosis in invasive ductal breast carc

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

    NARCIS (Netherlands)

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

    1995-01-01

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

  12. Divergent effects of insulin-like growth factor-1 receptor expression on prognosis of estrogen receptor positive versus triple negative invasive ductal breast carcinoma

    NARCIS (Netherlands)

    Hartog, Hermien; Horlings, Hugo M; van der Vegt, Bert; Kreike, Bas; Ajouaou, Abderrahim; van de Vijver, Marc J; Boezen, Hendrika; de Bock, Geertruida H; van der Graaf, Wilhelmina; Wesseling, Jelle

    2011-01-01

    The insulin-like growth factor type 1 receptor (IGF1R) is involved in progression of breast cancer and resistance to systemic treatment. Targeting IGF1R signaling may, therefore, be beneficial in systemic treatment. We report the effect of IGF1R expression on prognosis in invasive ductal breast carc

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

    NARCIS (Netherlands)

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

    1995-01-01

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

  14. EXPRESSION AND SIGNIFICANCE OF BASIC FIBROBLAST GWOWTH FACTOR AND FIBROBLAST GROWTH FACTOR RECEPTOR-1 IN OVARIAN EPITHELIAL NEOPLASM

    Institute of Scientific and Technical Information of China (English)

    高尚风; 杨蓉; 高博; 刘惠喜

    2003-01-01

    fibroblast growth factor (bFGF), fibroblast growth factor receptor-1 (FGFR-1) and carcinogenesis and progression of ovarian epithelial neoplasm. Methods Ten cases of normal ovarian tissues and 75 cases of ovarian epithelial neoplasm tissues were detected by immunohistochemical methods: S-P for bFGF, FGFR-1,double immunohistochemistry Lab-SA for Ki-67 antigen and bFGF. Results The expression level of bFGF, FGFR-1in ovarian epithelium and ovarian epithelial neoplasm showed a step-wise increase in the following order:normal〈benign〈borderline〈malignant; The expression level and intensity of bFGF and FGFR-1 were increased with the decrease of differentiation degree and increase of clinical stage in ovarian carcinoma; There was no statistical difference between the expression of bFGF, FGFR-1 in serous cystadenocarcinoma and that of mucinous cystadenocarcinoma; The expression of bFGF was correlated with that of FGFR-1 in neoplastic tissues; There were positive expression rates of bFGF and Ki-67 antigen in ovarian epithelial neoplasm. Conclusion As an important proliferative factor, bFGF plays an important role in carcinogenisis and progression of ovarian epithelial neoplasm.

  15. [Functional analysis of transforming growth factor-beta type II dominant negative receptor].

    Science.gov (United States)

    Takarada, M

    1996-06-01

    The transforming growth factor-beta (TGF-beta) is a multifunctional homodimeric protein with an apparent molecular weight of 25 KDa. TGF-beta transduces signals by forming heteromeric complexes of their type-I (T beta R-I) and type-II (T beta R-II) serin/threonine kinase receptors. TGF-beta binds first to T beta R-II receptor, and then the ligand in this complex is recognized by T beta R-I, resulting in formation of a heteromeric receptor complex composed of T beta R-I and T beta R-II. Once received, T beta R-I becomes phosphorylated in the GS domain by the associated constitutively active T beta R-II and transmits the downstream signal. It has been reported that formation of the heteromeric complex is indispensible at least in epithelial cells for growth inhibition and extracellular matrix production induced by TGF-beta. In this study, the functional role of T beta R-II for the TGF-beta-induced signals in osteoblastic cells was investigated by using a dominant negative type of T beta R-II mutant receptors (T beta RIIDNR). ROS 17/2.8 and MG 63 cells were found to express T beta R-I, T beta R-II, and T beta R-III, and their cell growth was inhibited by TGF-beta, whereas alkaline phosphatase activity was stimulated. Cells that were stably transfected with the T beta RIIDNR plasmid showed decreased response to TGF-beta during growth and alkaline phosphatase activity. These results indicate that the intracellular serine/threonine kinase domain of T beta R-II is essential for signal transduction of the TGF-beta-induced alkaline phosphatase activity as well as growth inhibition.

  16. Expression of osteoprotegerin, receptor activator of nuclear factor kappa-B ligand, tumor necrosis factor-related apoptosis-inducing ligand, stromal cell-derived factor-1 and their receptors in epithelial metastatic breast cancer cell lines

    Directory of Open Access Journals (Sweden)

    Labovsky Vivian

    2012-06-01

    Full Text Available Abstract Background While breast cancer (BC is the major cause of death among women worldwide, there is no guarantee of better patient survival because many of these patients develop primarily metastases, despite efforts to detect it in its early stages. Bone metastasis is a common complication that occurs in 65-80 % of patients with disseminated disease, but the molecular basis underlying dormancy, dissemination and establishment of metastasis is not understood. Our objective has been to evaluate simultaneously osteoprotegerin (OPG, receptor activator of nuclear factor kappa B ligand (RANKL, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL, stromal cell-derived factor-1 (SDF-1, and their receptors (R in 2 human BC cell lines, MDA-MB-231 and MCF-7. Methods OPG, RANKL, TRAIL and SDF-1 expression and release, in addition to the expression of their receptors has been investigated using immunofluorescence, immunocytochemistry and ELISA analyses. Results MCF-7 cells released higher levels of OPG in conditioned media (CM than MDA-MB-231 cells; 100 % of both types of cell expressed OPG, RANKL, TRAIL and SDF-1. Moreover, 100 % in both lines expressed membrane RANKL and RANK, whereas only 50 % expressed CXCR4. Furthermore, 100 % expressed TRAIL-R1 and R4, 30-50 % TRAIL-R2, and 40-55 % TRAIL-R3. Conclusions MCF-7 and MDA-MB-231 cells not only released OPG, but expressed RANKL, TRAIL and SDF-1. The majority of the cells also expressed RANK, CXCR4 and TRAIL-R. Since these ligands and their receptors are implicated in the regulation of proliferation, survival, migration and future bone metastasis during breast tumor progression, assessment of these molecules in tumor biopsies of BC patients could be useful in identifying patients with more aggressive tumors that are also at risk of bone metastasis, which may thus improve the available options for therapeutic intervention.

  17. Toxicity profile of epidermal growth factor receptor tyrosine kinase inhibitors in patients with epidermal growth factor receptor gene mutation-positive lung cancer

    Science.gov (United States)

    Takeda, Masayuki; Nakagawa, Kazuhiko

    2017-01-01

    Recent progress in the research on the molecular biology of lung cancer revealed that the clinical response to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) is associated with the presence of activating EGFR mutations. Three EGFR-TKIs, namely afatinib, erlotinib and gefitinib, are currently available for the treatment of patients with EGFR mutation-positive non-small-cell lung cancer (NSCLC). Due to the dearth of published phase III trials prospectively evaluating the effects of one EGFR-TKI in comparison with another in such patients, the decision-making regarding which agent to recommend to any given patient lies with the treating physician. Given the potential long-term exposure of such patients to EGFR-TKIs, the toxicological properties of these drugs in such patients may differ from those observed in unselected patients. The aim of the present study was to provide an overview of the key adverse events (rash, diarrhea, hepatotoxicity and interstitial lung disease) reported for EGFR-TKIs in clinical trials including patients with advanced NSCLC. PMID:28123721

  18. The Role of Epidermal Growth Factor Receptor Mutations and Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitors in the Treatment of Lung Cancer

    Directory of Open Access Journals (Sweden)

    Shih-Chieh Chang

    2011-06-01

    Full Text Available Lung cancer is the leading cause of cancer-related deaths worldwide. Non-small-cell lung cancer (NSCLC cases comprise approximately 85% of the lung cancer cases. Before the era of target therapy, platinum-based doublet chemotherapy only led to a median survival of 8–9 months and a one-year survival of 30%–40% in patients with advanced NSCLC. In July 2002, gefitinib, a small-molecule epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI, was approved for the treatment of patients with advanced NSCLC in Japan. After the widespread use of gefitinib in the treatment of NSCLC, there have been many new studies regarding the association between the clinical anticancer efficacy of gefitinib and the somatic EGFR mutation status in patients with NSCLC. This article summarizes the role of EGFR mutations in lung cancer and the use of EGFR antagonists in the treatment of lung cancer and its associated adverse effects.

  19. Adenosine inhibits neutrophil vascular endothelial growth factor release and transendothelial migration via A2B receptor activation.

    LENUS (Irish Health Repository)

    Wakai, A

    2012-02-03

    The effects of adenosine on neutrophil (polymorphonuclear neutrophils; PMN)-directed changes in vascular permeability are poorly characterized. This study investigated whether adenosine modulates activated PMN vascular endothelial growth factor (vascular permeability factor; VEGF) release and transendothelial migration. PMN activated with tumour necrosis factor-alpha (TNF-alpha, 10 ng\\/mL) were incubated with adenosine and its receptor-specific analogues. Culture supernatants were assayed for VEGF. PMN transendothelial migration across human umbilical vein endothelial cell (HUVEC) monolayers was assessed in vitro. Adhesion molecule receptor expression was assessed flow cytometrically. Adenosine and some of its receptor-specific analogues dose-dependently inhibited activated PMN VEGF release. The rank order of potency was consistent with the affinity profile of human A2B receptors. The inhibitory effect of adenosine was reversed by 3,7-dimethyl-1-propargylxanthine, an A2 receptor antagonist. Adenosine (100 microM) or the A2B receptor agonist 5\\'-N-ethylcarboxamidoadenosine (NECA, 100 microM) significantly reduced PMN transendothelial migration. However, expression of activated PMN beta2 integrins and HUVEC ICAM-1 were not significantly altered by adenosine or NECA. Adenosine attenuates human PMN VEGF release and transendothelial migration via the A2B receptor. This provides a novel target for the modulation of PMN-directed vascular hyperpermeability in conditions such as the capillary leak syndrome.

  20. A novel unidirectional cross-talk from the insulin-like growth factor-I receptor to leptin receptor in human breast cancer cells.

    Science.gov (United States)

    Ozbay, Tuba; Nahta, Rita

    2008-06-01

    Obesity is a major risk factor for the development and progression of breast cancer. Increased circulating levels of the obesity-associated hormones leptin and insulin-like growth factor-I (IGF-I) and overexpression of the leptin receptor (Ob-R) and IGF-I receptor (IGF-IR) have been detected in a majority of breast cancer cases and during obesity. Due to correlations between increased leptin, Ob-R, IGF-I, and IGF-IR in breast cancer, we hypothesized that molecular interactions may exist between these two signaling pathways. Coimmunoprecipitation and immunoblotting showed that IGF-IR and Ob-R interact in the breast cancer cell lines MDA-MB-231, MCF7, BT474, and SKBR3. Stimulation of cells with IGF-I promoted Ob-R phosphorylation, which was blocked by IGF-IR kinase inhibition. In addition, IGF-I activated downstream signaling molecules in the leptin receptor and IGF-IR pathways. In contrast to IGF-I, leptin did not induce phosphorylation of IGF-IR, indicating that receptor cross-signaling is unidirectional, occurring from IGF-IR to Ob-R. Our results show, for the first time, a novel interaction and cross-talk between the IGF-I and leptin receptors in human breast cancer cells.

  1. Soluble tumour necrosis factor receptor release after anti-CD3 monoclonal antibody treatment in mice is independent of tumour necrosis factor-alpha release.

    NARCIS (Netherlands)

    Vossen, A.C.T.M.; Tibbe, G.J.M.; Buurman, W.A.; Benner, R.; Savelkoul, H.F.J.

    1996-01-01

    Soluble tumour necrosis factor receptor release after anti-CD3 monoclonal antibody treatment in mice is independent of tumour necrosis factor-alpha release. Vossen AC, Tibbe GJ, Buurman WA, Benner R, Savelkoul HF. Department of Immunology, Erasmus University, Rotterdam, The Netherlands. The involvem

  2. Flow cytometric detection of growth factor receptors in autografts and analysis of growth factor concentrations in autologous stem cell transplantation: possible significance for platelet recovery

    DEFF Research Database (Denmark)

    Schiødt, I; Jensen, Charlotte Harken; Kjaersgaard, E

    2000-01-01

    In order to improve prediction of hematopoietic recovery, we conducted a pilot study, analyzing the significance of growth factor receptor expression in autografts as well as endogenous growth factor levels in blood before, during and after stem cell transplantation. Three early acting (stem cell...

  3. Grape seed extract inhibits angiogenesis via suppression of the vascular endothelial growth factor receptor signaling pathway.

    Science.gov (United States)

    Wen, Wei; Lu, Jianming; Zhang, Keqiang; Chen, Shiuan

    2008-12-01

    Blockade of angiogenesis is an important approach for cance