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

    DEFF Research Database (Denmark)

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

    2008-01-01

    The neural cell adhesion molecule (NCAM) plays important roles in neuronal development, regeneration, and synaptic plasticity. NCAM homophilic binding mediates cell adhesion and induces intracellular signals, in which the fibroblast growth factor receptor plays a prominent role. Recent studies on...... this NCAM-180-induced EGFR down-regulation involves increased EGFR ubiquitination and lysosomal EGFR degradation. Furthermore, NCAM-180-mediated EGFR down-regulation requires NCAM homophilic binding and interactions of the cytoplasmic domain of NCAM-180 with intracellular interaction partners, but does...

  2. Active G protein-coupled receptors (GPCR), matrix metalloproteinases 2/9 (MMP2/9), heparin-binding epidermal growth factor (hbEGF), epidermal growth factor receptor (EGFR), erbB2, and insulin-like growth factor 1 receptor (IGF-1R) are necessary for trenbolone acetate-induced alterations in protein turnover rate of fused bovine satellite cell cultures.

    Science.gov (United States)

    Thornton, K J; Kamanga-Sollo, E; White, M E; Dayton, W R

    2016-06-01

    Trenbolone acetate (TBA), a testosterone analog, increases protein synthesis and decreases protein degradation in fused bovine satellite cell (BSC) cultures. However, the mechanism through which TBA alters these processes remains unknown. Recent studies indicate that androgens improve rate and extent of muscle growth through a nongenomic mechanism involving G protein-coupled receptors (GPCR), matrix metalloproteinases (MMP), heparin-binding epidermal growth factor (hbEGF), the epidermal growth factor receptor (EGFR), erbB2, and the insulin-like growth factor-1 receptor (IGF-1R). We hypothesized that TBA activates GPCR, resulting in activation of MMP2/9 that releases hbEGF, which activates the EGFR and/or erbB2. To determine whether the proposed nongenomic pathway is involved in TBA-mediated alterations in protein turnover, fused BSC cultures were treated with TBA in the presence or absence of inhibitors for GPCR, MMP2/9, hbEGF, EGFR, erbB2, or IGF-1R, and resultant protein synthesis and degradation rates were analyzed. Assays were replicated at least 9 times for each inhibitor experiment utilizing BSC cultures obtained from at least 3 different steers that had no previous exposure to steroid compounds. As expected, fused BSC cultures treated with 10 n TBA exhibited increased ( BSC cultures with 10 n TBA in the presence of inhibitors for GPCR, MMP2/9, hbEGF, EGFR, erbB2, or IGF-1R suppressed ( 0.05) effect on TBA-mediated decreases in protein degradation. However, inhibition of both EGFR and erbB2 in the presence of 10 n TBA resulted in decreased ( BSC cultures treated with 10 n TBA exhibit increased ( BSC cultures.

  3. Hypoxia activated EGFR signaling induces epithelial to mesenchymal transition (EMT.

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    Ashish Misra

    Full Text Available Metastasis is a multi-step process which requires the conversion of polarized epithelial cells to mesenchymal cells, Epithelial-Mesenchymal Transition (EMT. EMT is essential during embryonic morphogenesis and has been implicated in the progression of primary tumors towards metastasis. Hypoxia is known to induce EMT; however the molecular mechanism is still poorly understood. Using the A431 epithelial cancer cell line, we show that cells grown under hypoxic conditions migrated faster than cells grown under normal oxygen environment. Cells grown under hypoxia showed reduced adhesion to the extracellular matrix (ECM probably due to reduced number of Vinculin patches. Growth under hypoxic conditions also led to down regulation of E-cadherin and up regulation of vimentin expression. The increased motility of cells grown under hypoxia could be due to redistribution of Rac1 to the plasma membrane as opposed to increased expression of Rac1. EGF (Epidermal Growth Factor is a known inducer of EMT and growth of A431 cells in the absence of oxygen led to increased expression of EGFR (EGF Receptor. Treatment of A431 cells with EGF led to reduced cell adhesion to ECM, increased cell motility and other EMT characteristics. Furthermore, this transition was blocked by the monoclonal antibody Cetuximab. Cetuximab also blocked the hypoxia-induced EMT suggesting that cell growth under hypoxic conditions led to activation of EGFR signaling and induction of EMT phenotype.

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

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    Christy E Trussoni

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

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

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

    2015-01-01

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

  6. EBP50 inhibits EGF-induced breast cancer cell proliferation by blocking EGFR phosphorylation.

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    Yao, Wenfang; Feng, Duiping; Bian, Weihua; Yang, Longyan; Li, Yang; Yang, Zhiyu; Xiong, Ying; Zheng, Junfang; Zhai, Renyou; He, Junqi

    2012-11-01

    Ezrin-radixin-moesin-binding phosphoprotein-50 (EBP50) suppresses breast cancer cell proliferation, potentially through its regulatory effect on epidermal growth factor receptor (EGFR) signaling, although the mechanism by which this occurs remains unknown. Thus in our studies, we aimed to determine the effect of EBP50 expression on EGF-induced cell proliferation and activation of EGFR signaling in the breast cancer cell lines, MDA-MB-231 and MCF-7. In MDA-MB-231 cells, which express low levels of EBP50, EBP50 overexpression inhibited EGF-induced cell proliferation, ERK1/2 and AKT phosphorylation. In MCF-7 cells, which express high levels of EBP50, EBP50 knockdown promoted EGF-induced cell proliferation, ERK1/2 and AKT phosphorylation. Knockdown of EBP50 in EBP50-overexpressed MDA-MB-231 cells abrogated the inhibitory effect of EBP50 on EGF-stimulated ERK1/2 phosphorylation and restoration of EBP50 expression in EBP50-knockdown MCF-7 cells rescued the inhibition of EBP50 on EGF-stimulated ERK1/2 phosphorylation, further confirming that the activation of EGF-induced downstream molecules could be specifically inhibited by EBP50 expression. Since EGFR signaling was triggered by EGF ligands via EGFR phosphorylation, we further detected the phosphorylation status of EGFR in the presence or absence of EBP50 expression. Overexpression of EBP50 in MDA-MB-231 cells inhibited EGF-stimulated EGFR phosphorylation, whereas knockdown of EBP50 in MCF-7 cells enhanced EGF-stimulated EGFR phosphorylation. Meanwhile, total expression levels of EGFR were unaffected during EGF stimulation. Taken together, our data shows that EBP50 can suppress EGF-induced proliferation of breast cancer cells by inhibiting EGFR phosphorylation and blocking EGFR downstream signaling in breast cancer cells. These results provide further insight into the molecular mechanism by which EBP50 regulates the development and progression of breast cancer.

  7. Acetate supplementation attenuates lipopolysaccharide-induced neuroinflammation.

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    Reisenauer, Chris J; Bhatt, Dhaval P; Mitteness, Dane J; Slanczka, Evan R; Gienger, Heidi M; Watt, John A; Rosenberger, Thad A

    2011-04-01

    Glyceryl triacetate (GTA), a compound effective at increasing circulating and tissue levels of acetate was used to treat rats subjected to a continual 28 day intra-ventricular infusion of bacterial lipopolysaccharide (LPS). This model produces a neuroinflammatory injury characterized by global neuroglial activation and a decrease in choline acetyltransferase immunoreactivity in the basal forebrain. During the LPS infusion, rats were given a daily treatment of either water or GTA at a dose of 6 g/kg by oral gavage. In parallel experiments, free-CoA and acetyl-CoA levels were measured in microwave fixed brains and flash frozen heart, liver, kidney and muscle following a single oral dose of GTA. We found that a single oral dose of GTA significantly increased plasma acetate levels by 15 min and remained elevated for up to 4 h. At 30 min the acetyl-CoA levels in microwave-fixed brain and flash frozen heart and liver were increased at least 2.2-fold. The concentrations of brain acetyl-CoA was significantly increased between 30 and 45 min following treatment and remained elevated for up to 4 h. The concentration of free-CoA in brain was significantly decreased compared to controls at 240 min. Immunohistochemical and morphological analysis demonstrated that a daily treatment with GTA significantly reduced the percentage of reactive glial fibrillary acidic protein-positive astrocytes and activated CD11b-positive microglia by 40-50% in rats subjected to LPS-induced neuroinflammation. Further, in rats subjected to neuroinflammation, GTA significantly increased the number of choline acetyltransferase (ChAT)-positive cells by 40% in the basal forebrain compared to untreated controls. These data suggest that acetate supplementation increases intermediary short chain acetyl-CoA metabolism and that treatment is potentially anti-inflammatory and neuroprotective with regards to attenuating neuroglial activation and increasing ChAT immunoreactivity in this model. PMID:21272004

  8. Involvement of lipid rafts in adhesion-induced activation of Met and EGFR

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    Lu Ying-Che

    2011-10-01

    Full Text Available Abstract Background Cell adhesion has been shown to induce activation of certain growth factor receptors in a ligand-independent manner. However, the mechanism for such activation remains obscure. Methods Human epidermal carcinoma A431 cells were used as a model to examine the mechanism for adhesion-induced activation of hepatocyte growth factor receptor Met and epidermal growth factor receptor (EGFR. The cells were suspended and replated on culture dishes under various conditions. The phosphorylation of Met at Y1234/1235 and EGFR at Y1173 were used as indicators for their activation. The distribution of the receptors and lipid rafts on the plasma membrane were visualized by confocal fluorescent microscopy and total internal reflection microscopy. Results We demonstrate that Met and EGFR are constitutively activated in A431 cells, which confers proliferative and invasive potentials to the cells. The ligand-independent activation of Met and EGFR in A431 cells relies on cell adhesion to a substratum, but is independent of cell spreading, extracellular matrix proteins, and substratum stiffness. This adhesion-induced activation of Met and EGFR cannot be attributed to Src activation, production of reactive oxygen species, and the integrity of the cytoskeleton. In addition, we demonstrate that Met and EGFR are independently activated upon cell adhesion. However, partial depletion of Met and EGFR prevents their activation upon cell adhesion, suggesting that overexpression of the receptors is a prerequisite for their self-activation upon cell adhesion. Although Met and EGFR are largely distributed in 0.04% Triton-insoluble fractions (i.e. raft fraction, their activated forms are detected mainly in 0.04% Triton-soluble fractions (i.e. non-raft fraction. Upon cell adhesion, lipid rafts are accumulated at the cell surface close to the cell-substratum interface, while Met and EGFR are mostly excluded from the membrane enriched by lipid rafts. Conclusions

  9. Pharmacological inhibition of EGFR signaling enhances G-CSF-induced hematopoietic stem cell mobilization.

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    Ryan, Marnie A; Nattamai, Kalpana J; Xing, Ellen; Schleimer, David; Daria, Deidre; Sengupta, Amitava; Köhler, Anja; Liu, Wei; Gunzer, Matthias; Jansen, Michael; Ratner, Nancy; Le Cras, Timothy D; Waterstrat, Amanda; Van Zant, Gary; Cancelas, Jose A; Zheng, Yi; Geiger, Hartmut

    2010-10-01

    Mobilization of hematopoietic stem and progenitor cells (HSPCs) from bone marrow into peripheral blood by the cytokine granulocyte colony-stimulating factor (G-CSF) has become the preferred source of HSPCs for stem cell transplants. However, G-CSF fails to mobilize sufficient numbers of stem cells in up to 10% of donors, precluding autologous transplantation in those donors or substantially delaying transplant recovery time. Consequently, new regimens are needed to increase the number of stem cells in peripheral blood upon mobilization. Using a forward genetic approach in mice, we mapped the gene encoding the epidermal growth factor receptor (Egfr) to a genetic region modifying G-CSF-mediated HSPC mobilization. Amounts of EGFR in HSPCs inversely correlated with the cells' ability to be mobilized by G-CSF, implying a negative role for EGFR signaling in mobilization. In combination with G-CSF treatment, genetic reduction of EGFR activity in HSPCs (in waved-2 mutant mice) or treatment with the EGFR inhibitor erlotinib increased mobilization. Increased mobilization due to suppression of EGFR activity correlated with reduced activity of cell division control protein-42 (Cdc42), and genetic Cdc42 deficiency in vivo also enhanced G-CSF-induced mobilization. Our findings reveal a previously unknown signaling pathway regulating stem cell mobilization and provide a new pharmacological approach for improving HSPC mobilization and thereby transplantation outcomes. PMID:20871610

  10. Loss of EBP50 stimulates EGFR activity to induce EMT phenotypic features in biliary cancer cells.

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    Clapéron, A; Guedj, N; Mergey, M; Vignjevic, D; Desbois-Mouthon, C; Boissan, M; Saubaméa, B; Paradis, V; Housset, C; Fouassier, L

    2012-03-15

    Scaffold proteins form multiprotein complexes that are central to the regulation of intracellular signaling. The scaffold protein ezrin-radixin-moesin-binding phosphoprotein 50 (EBP50) is highly expressed at the plasma membrane of normal biliary epithelial cells and binds epidermal growth factor receptor (EGFR), a tyrosine kinase receptor with oncogenic properties. This study investigated EBP50-EGFR interplay in biliary cancer. We report that in a collection of 106 cholangiocarcinomas, EBP50 was delocalized to the cytoplasm of tumor cells in 66% of the cases. Ectopic expression of EBP50 was correlated with the presence of satellite nodules and with the expression of EGFR, which was at the plasma membrane, implying a loss of interaction with EBP50 in these cases. In vitro, loss of interaction between EBP50 and EGFR was mimicked by EBP50 depletion using a small interfering RNA approach in human biliary carcinoma cells co-expressing the two proteins at their plasma membrane, and in which interaction between EBP50 and EGFR was validated. EBP50 depletion caused an increase in EGFR expression at their surface, and a sustained activation of the receptor and of its downstream effectors (extracellular signal-regulated kinase 1/2, signal transducer and activator of transcription 3) in both basal and EGF-stimulated conditions. Cells lacking EBP50 showed epithelial-to-mesenchymal transition-associated features, including reduction in E-cadherin and cytokeratin-19 expression, induction of S100A4 and of the E-cadherin transcriptional repressor, Slug, and loss of cell polarity. Accordingly, depletion of EBP50 induced the disruption of adherens junctional complexes, the development of lamellipodia structures and the subsequent acquisition of motility properties. All these phenotypic changes were prevented upon inhibition of EGFR tyrosine kinase by gefitinib. These findings indicate that loss of EBP50 at the plasma membrane in tumor cells may contribute to biliary carcinogenesis

  11. Pan-HER-An antibody mixture targeting EGFR, HER2 and HER3 abrogates preformed and ligand-induced EGFR homo- and heterodimers.

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    Ellebaek, Sofie; Brix, Susanne; Grandal, Michael; Lantto, Johan; Horak, Ivan D; Kragh, Michael; Poulsen, Thomas Tuxen

    2016-11-01

    The human epidermal growth factor receptor (HER)-family is involved in development of many epithelial cancers. Therefore, HER-family members constitute important targets for anti-cancer therapeutics such as monoclonal antibodies (mAbs). A limitation to the success of single HER-targeting mAbs is development of acquired resistance through mechanisms such as alterted receptor dimerization patterns and dependencies. Pan-HER is a mixture of six mAbs simultaneously targeting epidermal growth factor receptor (EGFR), HER2 and HER3 with two mAbs against each receptor. Pan-HER has previously demonstrated broader efficacy than targeting single or dual receptor combinations also in resistant settings. In light of this broad efficacy, we decided to investigate the effect of Pan-HER compared with single HER-targeting with single and dual mAbs on HER-family cross-talk and dimerization focusing on EGFR. The effect of Pan-HER on cell proliferation and HER-family receptor degradation was superior to treatment with single mAbs targeting either single receptor, and similar to targeting a single receptor with two non-overlapping antibodies. Furthermore, changes in EGFR-dimerization patterns after treatment with Pan-HER were investigated by in situ proximity ligation assay and co-immunoprecipitation, demonstrating that Pan-HER and the EGFR-targeting mAb mixture efficiently down-regulate basal EGFR homo- and heterodimerization in two tested cell lines, whereas single mAbs had limited effects. Pan-HER and the EGFR-targeting mAb mixture also blocked EGF-binding and thereby ligand-induced changes in EGFR-dimerization levels. These results suggest that Pan-HER reduces the cellular capability to switch HER-dependency and dimerization pattern in response to treatment and thus hold promise for future clinical development of Pan-HER in resistant settings.

  12. Pan-HER-An antibody mixture targeting EGFR, HER2 and HER3 abrogates preformed and ligand-induced EGFR homo- and heterodimers.

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    Ellebaek, Sofie; Brix, Susanne; Grandal, Michael; Lantto, Johan; Horak, Ivan D; Kragh, Michael; Poulsen, Thomas Tuxen

    2016-11-01

    The human epidermal growth factor receptor (HER)-family is involved in development of many epithelial cancers. Therefore, HER-family members constitute important targets for anti-cancer therapeutics such as monoclonal antibodies (mAbs). A limitation to the success of single HER-targeting mAbs is development of acquired resistance through mechanisms such as alterted receptor dimerization patterns and dependencies. Pan-HER is a mixture of six mAbs simultaneously targeting epidermal growth factor receptor (EGFR), HER2 and HER3 with two mAbs against each receptor. Pan-HER has previously demonstrated broader efficacy than targeting single or dual receptor combinations also in resistant settings. In light of this broad efficacy, we decided to investigate the effect of Pan-HER compared with single HER-targeting with single and dual mAbs on HER-family cross-talk and dimerization focusing on EGFR. The effect of Pan-HER on cell proliferation and HER-family receptor degradation was superior to treatment with single mAbs targeting either single receptor, and similar to targeting a single receptor with two non-overlapping antibodies. Furthermore, changes in EGFR-dimerization patterns after treatment with Pan-HER were investigated by in situ proximity ligation assay and co-immunoprecipitation, demonstrating that Pan-HER and the EGFR-targeting mAb mixture efficiently down-regulate basal EGFR homo- and heterodimerization in two tested cell lines, whereas single mAbs had limited effects. Pan-HER and the EGFR-targeting mAb mixture also blocked EGF-binding and thereby ligand-induced changes in EGFR-dimerization levels. These results suggest that Pan-HER reduces the cellular capability to switch HER-dependency and dimerization pattern in response to treatment and thus hold promise for future clinical development of Pan-HER in resistant settings. PMID:27342948

  13. EMT-induced stemness and tumorigenicity are fueled by the EGFR/Ras pathway.

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    Dominic Chih-Cheng Voon

    Full Text Available Recent studies have revealed that differentiated epithelial cells would acquire stem cell-like and tumorigenic properties following an Epithelial-Mesenchymal Transition (EMT. However, the signaling pathways that participate in this novel mechanism of tumorigenesis have not been fully characterized. In Runx3 (-/- p53 (-/- murine gastric epithelial (GIF-14 cells, EMT-induced plasticity is reflected in the expression of the embryonal proto-oncogene Hmga2 and Lgr5, an exclusive gastrointestinal stem cell marker. Here, we report the concurrent activation of an EGFR/Ras gene expression signature during TGF-β1-induced EMT in GIF-14 cells. Amongst the altered genes was the induction of Egfr, which corresponded with a delayed sensitization to EGF treatment in GIF-14. Co-treatment with TGF-β1 and EGF or the expression of exogenous KRas led to increased Hmga2 or Lgr5 expression, sphere initiation and colony formation in soft agar assay. Interestingly, the gain in cellular plasticity/tumorigenicity was not accompanied by increased EMT. This uncoupling of EMT and the induction of plasticity reveals an involvement of distinct signaling cues, whereby the EGFR/Ras pathway specifically promotes stemness and tumorigenicity in EMT-altered GIF-14 cells. These data show that the EGFR/Ras pathway requisite for the sustenance of gastric stem cells in vivo and in vitro is involved in the genesis and promotion of EMT-induced tumor-initiating cells.

  14. Alpha6beta4 integrin crosslinking induces EGFR clustering and promotes EGF-mediated Rho activation in breast cancer

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    Woodward Wendy A

    2009-05-01

    Full Text Available Abstract Background The α6β4 integrin is overexpressed in the basal subtype of breast cancer and plays an important role in tumor cell motility and invasion. EGFR is also overexpressed in the basal subtype of breast cancer, and crosstalk between α6β4 integrin and EGFR appears to be important in tumor progression. Methods We evaluated the effects of α6β4 crosslinking on the distribution and function of EGFR in breast carcinoma cell line MDA-MB-231. Receptor distribution was evaluated by fluorescence microscopy and multispectral imaging flow cytometry, and ligand-mediated EGFR signaling was evaluated using Western blots and a Rho pull-down assay. Results Antibody-mediated crosslinking of α6β4 integrin was sufficient to induce cell-surface clustering of not only α6β4 but also EGFR in nonadherent cells. The induced clustering of EGFR was observed minimally after 5 min of integrin crosslinking but was more prominent after 15 min. EGFR clustering had minimal effect on the phosphorylation of Akt or Erk1,2 in response to EGF in suspended cells or in response to HB-EGF in adherent cells. However, EGFR clustering induced by crosslinking α6β4 had a marked effect on Rho activation in response to EGF. Conclusion Crosslinking α6β4 integrin in breast carcinoma cells induces EGFR clustering and preferentially promotes Rho activation in response to EGF. We hypothesize that this integrin-EGFR crosstalk may facilitate tumor cell cytoskeletal rearrangements important for tumor progression.

  15. K-RAS(V12) Induces Autocrine Production of EGFR Ligands and Mediates Radioresistance Through EGFR-Dependent Akt Signaling and Activation of DNA-PKcs

    International Nuclear Information System (INIS)

    Purpose: It is known that postirradiation survival of tumor cells presenting mutated K-RAS is mediated through autocrine activation of epidermal growth factor receptor (EGFR). In this study the molecular mechanism of radioresistance of cells overexpressing mutated K-RAS(V12) was investigated. Methods and Materials: Head-and-neck cancer cells (FaDu) presenting wild-type K-RAS were transfected with empty vector or vector expressing mutated K-RAS(V12). The effect of K-RAS(V12) on autocrine production of EGFR ligands, activation of EGFR downstream pathways, DNA damage repair, and postirradiation survival was analyzed. Results: Conditioned medium collected from K-RAS(V12)–transfected cells enhanced activation of the phosphatidylinositol-3-kinase–Akt pathway and increased postirradiation survival of wild-type K-RAS parental cells when compared with controls. These effects were reversed by amphiregulin (AREG)–neutralizing antibody. In addition, secretion of the EGFR ligands AREG and transforming growth factor α was significantly increased upon overexpression of K-RAS(V12). Expression of mutated K-RAS(V12) resulted in an increase in radiation-induced DNA-dependent protein kinase catalytic subunit (DNA-PKcs) phosphorylation at S2056. This increase was accompanied by increased repair of DNA double-strand breaks. Abrogation of DNA-PKcs phosphorylation by serum depletion or AREG-neutralizing antibody underscored the role of autocrine production of EGFR ligands, namely, AREG, in regulating DNA-PKcs activation in K-RAS mutated cells. Conclusions: These data indicate that radioresistance of K-RAS mutated tumor cells is at least in part due to constitutive production of EGFR ligands, which mediate enhanced repair of DNA double-strand breaks through the EGFR–phosphatidylinositol-3-kinase–Akt cascade.

  16. Acetate supplementation attenuates lipopolysaccharide-induced neuroinflammation

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    Reisenauer, Chris J.; Bhatt, Dhaval P.; Mitteness, Dane J.; Slanczka, Evan R.; Gienger, Heidi M.; Watt, John A.; Rosenberger, Thad A

    2011-01-01

    Glyceryl triacetate (GTA), a compound effective at increasing circulating and tissue levels of acetate was used to treat rats subjected to a continual 28 day intra-ventricular infusion of bacterial lipopolysaccharide (LPS). This model produces a neuroinflammatory injury characterized by global neuroglial activation and a decrease in choline acetyltransferase immunoreactivity in the basal forebrain. During the LPS infusion, rats were given a daily treatment of either water or GTA at a dose of ...

  17. Bufalin Reverses HGF-Induced Resistance to EGFR-TKIs in EGFR Mutant Lung Cancer Cells via Blockage of Met/PI3k/Akt Pathway and Induction of Apoptosis

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    Xiao-Hong Kang

    2013-01-01

    Full Text Available The epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs, such as gefitinib and erlotinib, have shown promising therapeutic efficacy in nonsmall cell lung cancer (NSCLC patients harboring epidermal growth factor receptor- (EGFR- activating mutation. However, the inevitable recurrence resulting from acquired resistance has limited the clinical improvement in therapy outcomes. Many studies demonstrate that hepatocyte growth factor- (HGF- Met axis plays an important role in tumor progression and drug sensitivity. HGF may induce resistance to EGFR-TKIs in EGFR mutant lung cancer cells by Met/PI3K/Akt signaling. The purpose of this study was to determine whether bufalin, a major bioactive component of Venenum Bufonis, could reverse HGF-induced resistance to reversible and irreversible EGFR-TKIs in mutant lung cancer cells PC-9, HCC827, and H1975. Our studies showed that bufalin could reverse resistance to reversible and irreversible EGFR-TKIs induced by exogenous HGF in EGFR mutant lung cancer cells by inhibiting the Met/PI3K/Akt pathway and inducing death signaling. These results suggested that bufalin might have a potential to overcome HGF-induced resistance to molecular-targeted drugs for lung cancer.

  18. Oncogenic EGFR Represses the TET1 DNA Demethylase to Induce Silencing of Tumor Suppressors in Cancer Cells

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    Matteo Forloni

    2016-07-01

    Full Text Available Oncogene-induced DNA methylation-mediated transcriptional silencing of tumor suppressors frequently occurs in cancer, but the mechanism and functional role of this silencing in oncogenesis are not fully understood. Here, we show that oncogenic epidermal growth factor receptor (EGFR induces silencing of multiple unrelated tumor suppressors in lung adenocarcinomas and glioblastomas by inhibiting the DNA demethylase TET oncogene family member 1 (TET1 via the C/EBPα transcription factor. After oncogenic EGFR inhibition, TET1 binds to tumor suppressor promoters and induces their re-expression through active DNA demethylation. Ectopic expression of TET1 potently inhibits lung and glioblastoma tumor growth, and TET1 knockdown confers resistance to EGFR inhibitors in lung cancer cells. Lung cancer samples exhibited reduced TET1 expression or TET1 cytoplasmic localization in the majority of cases. Collectively, these results identify a conserved pathway of oncogenic EGFR-induced DNA methylation-mediated transcriptional silencing of tumor suppressors that may have therapeutic benefits for oncogenic EGFR-mediated lung cancers and glioblastomas.

  19. TGFβ induces proHB-EGF shedding and EGFR transactivation through ADAM activation in gastric cancer cells

    International Nuclear Information System (INIS)

    Research highlights: → TGFβ induces EGFR transactivation through proHB-EGF shedding by activated ADAM members in gastric cancer cells. → TGFβ induces nuclear translocation of HB-EGF-CTF cleaved by ADAM members. → TGFβ enhances cell growth by EGFR transactivation and HB-EGF-CTF nuclear translocation and ADAM inhibitors block these effects. → Silencing of ADAM17 also blocks EGFR transactivation, HB-EGF-CTF nuclear translocation and cancer cell growth by TGFβ. → ADAM17 may play a crucial role in this TGFβ-HB-EGF signal transduction. -- Abstract: Background and aims: Transforming growth factor-beta (TGFβ) is known to potently inhibit cell growth. Loss of responsiveness to TGFβ inhibition on cell growth is a hallmark of many types of cancer, yet its mechanism is not fully understood. Membrane-anchored heparin-binding EGF-like growth factor (proHB-EGF) ectodomain is cleaved by a disintegrin and metalloproteinase (ADAM) members and is implicated in epidermal growth factor receptor (EGFR) transactivation. Recently, nuclear translocation of the C-terminal fragment (CTF) of pro-HB-EGF was found to induce cell growth. We investigated the association between TGFβ and HB-EGF signal transduction via ADAM activation. Materials and methods: The CCK-8 assay in two gastric cancer cell lines was used to determine the effect for cell growth by TGFβ. The effect of two ADAM inhibitors was also evaluated. Induction of EGFR phosphorylation by TGFβ was analyzed and the effect of the ADAM inhibitors was also examined. Nuclear translocation of HB-EGF-CTF by shedding through ADAM activated by TGFβ was also analyzed. EGFR transactivation, HB-EGF-CTF nuclear translocation, and cell growth were examined under the condition of ADAM17 knockdown. Result: TGFβ-induced EGFR phosphorylation of which ADAM inhibitors were able to inhibit. TGFβ induced shedding of proHB-EGF allowing HB-EGF-CTF to translocate to the nucleus. ADAM inhibitors blocked this nuclear translocation. TGF

  20. Regulation of EGF-induced ERK/MAPK Activation and EGFR Internalization by G Protein-coupled Receptor Kinase 2

    Institute of Scientific and Technical Information of China (English)

    Jingxia GAO; Jiali LI; Lan MA

    2005-01-01

    G protein-coupled receptor kinases (GRKs) mediate agonist-induced phosphorylation and desensitization of various G protein-coupled receptors (GPCRs). We investigate the role of GRK2 on epidermal growth factor (EGF) receptor signaling, including EGF-induced extracellular signal-regulated kinase and mitogen-activated protein kinase (ERK/MAPK) activation and EGFR internalization. Immunoprecipitation and immunofluorescence experiments show that EGF stimulates GRK2 binding to EGFR complex and GRK2 translocating from cytoplasm to the plasma membrane in human embryonic kidney 293 cells. Western blotting assay shows that EGF-induced ERK/MAPK phosphorylation increases 1.9-fold, 1.1-fold and 1.5-fold (P<0.05) at time point 30, 60 and 120 min, respectively when the cells were transfected with GRK2,suggesting the regulatory role of GRK2 on EGF-induced ERK/MAPK activation. Flow cytometry experiments show that GRK2 overexpression has no effect on EGF-induced EGFR internalization, however, it increases agonist-induced G protein-coupled δ opioid receptor internalization by approximately 40% (P<0.01). Overall,these data suggest that GRK2 has a regulatory role in EGF-induced ERK/MAPK activation, and that the mechanisms underlying the modulatory role of GRK2 in EGFR and GPCR signaling pathways are somewhat different at least in receptor internalization.

  1. Anterior Gradient 2 (AGR2) Induced Epidermal Growth Factor Receptor (EGFR) Signaling Is Essential for Murine Pancreatitis-Associated Tissue Regeneration

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    Wodziak, Dariusz; Dong, Aiwen; Basin, Michael F.; Lowe, Anson W.

    2016-01-01

    A recently published study identified Anterior Gradient 2 (AGR2) as a regulator of EGFR signaling by promoting receptor presentation from the endoplasmic reticulum to the cell surface. AGR2 also promotes tissue regeneration in amphibians and fish. Whether AGR2-induced EGFR signaling is essential for tissue regeneration in higher vertebrates was evaluated using a well-characterized murine model for pancreatitis. The impact of AGR2 expression and EGFR signaling on tissue regeneration was evaluated using the caerulein-induced pancreatitis mouse model. EGFR signaling and cell proliferation were examined in the context of the AGR2-/- null mouse or with the EGFR-specific tyrosine kinase inhibitor, AG1478. In addition, the Hippo signaling coactivator YAP1 was evaluated in the context of AGR2 expression during pancreatitis. Pancreatitis-induced AGR2 expression enabled EGFR translocation to the plasma membrane, the initiation of cell signaling, and cell proliferation. EGFR signaling and tissue regeneration were partially inhibited by the tyrosine kinase inhibitor AG1478, but absent in the AGR2-/- null mouse. AG1478-treated and AGR2-/- null mice with pancreatitis died whereas all wild-type controls recovered. YAP1 activation was also dependent on pancreatitis-induced AGR2 expression. AGR2-induced EGFR signaling was essential for tissue regeneration and recovery from pancreatitis. The results establish tissue regeneration as a major function of AGR2-induced EGFR signaling in adult higher vertebrates. Enhanced AGR2 expression and EGFR signaling are also universally present in human pancreatic cancer, which support a linkage between tissue injury, regeneration, and cancer pathogenesis. PMID:27764193

  2. Nicotinamide attenuates aquaporin 3 overexpression induced by retinoic acid through inhibition of EGFR/ERK in cultured human skin keratinocytes.

    Science.gov (United States)

    Song, Xiuzu; Xu, Aie; Pan, Wei; Wallin, Brittany; Kivlin, Rebecca; Lu, Shan; Cao, Cong; Bi, Zhigang; Wan, Yinsheng

    2008-08-01

    The most common adverse effects that are related to all-trans retinoic acid (atRA) treatment are irritation and dryness of the skin. atRA therapy is reported to impair barrier function as achieved by trans-epidermal water loss (TEWL). Treatment with nicotinamide prior to initiation of atRA therapy provides additional barrier protection and thus reduces susceptibility of retinoic acid. Our previous studies showed that atRA upregulates aquaporin 3 (AQP3) in cultured human skin keratinocytes and fibroblasts. Others have demonstrated that in atopic dermatitis, overexpression of AQP3 is linked to elevated TEWL and that nicotinamide treatment reduces skin TEWL. In this study, we observed that while atRA upregulates AQP3 expression in cultured human skin keratinocytes (HaCaT cells), nicotinamide attenuates the effect of atRA in a concentration-dependent manner. atRA treatment induces EGFR and ERK activation. PD153035, an EGFR inhibitor, and U0126, an ERK inhibitor, inhibit atRA-induced upregulation of AQP3. Nicotinamide also inhibits atRA-induced activation of EGFR/ERK signal transduction and decreases water permeability by downregulating AQP3 expression. Collectively, our results indicate that the effect of atRA on AQP3 expression is at least partly mediated by EGFR/ERK signaling in cultured human skin keratinocytes. Nicotinamide attenuates atRA-induced AQP3 expression through inhibition of EGFR/ERK signal transduction and eventually decreases water permeability and water loss. Our study provides insights into the molecular mechanism through which nicotinamide reverses the side effects of dryness in human skin after treatment with atRA.

  3. Ofloxacin induces apoptosis via β1 integrin-EGFR-Rac1-Nox2 pathway in microencapsulated chondrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Sheng, Zhi-Guo [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Huang, Wei [Department of Chemical Biology, School of Pharmaceutical Sciences, Peking University Health Science Center, Beijing 1000191 (China); Liu, Yu-Xiang [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Yuan, Ye [Beijing Institute of Pharmacology and Toxicology, 27 Taiping Road, Beijing 100850 (China); Zhu, Ben-Zhan, E-mail: bzhu@rcees.ac.cn [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Linus Pauling Institute, Oregon State University, Corvallis, OR 97331 (United States)

    2013-02-15

    Quinolones (QNs)-induced arthropathy is an important toxic side-effect in immature animals leading to the restriction of their therapeutic use in pediatrics. Ofloxacin, a typical QN, was found to induce the chondrocytes apoptosis in the early phase (12–48 h) of arthropathy in our previous study. However, the exact mechanism(s) is unclear. Microencapsulated juvenile rabbit joint chondrocytes, a three-dimensional culture system, is utilized to perform the present study. Ofloxacin, at a therapeutically relevant concentration (10 μg/ml), disturbs the interaction between β1 integrin and activated intracellular signaling proteins at 12 h, which is inhibited when supplementing Mg{sup 2+}. Intracellular reactive oxygen species (ROS) significantly increases in a time-dependent manner after exposure to ofloxacin for 12–48 h. Furthermore, ofloxacin markedly enhances the level of activated Rac1 and epidermal growth factor receptor (EGFR) phosphorylation, and its inhibition in turn reduces the ROS production, apoptosis and Rac1 activation. Silencing Nox2, Rac1 or supplementing Mg{sup 2+} inhibits ROS accumulation, apoptosis occurrence and EGFR phosphorylation induced by ofloxacin. However, depletion of Nox2, Rac1 and inhibition of EGFR do not affect ofloxacin-mediated loss of interaction between β1 integrin and activated intracellular signaling proteins. In addition, ofloxacin also induces Vav2 phosphorylation, which is markedly suppressed after inactivating EGFR or supplementing Mg{sup 2+}. These results suggest that ofloxacin causes Nox2-mediated intracellular ROS production by disrupting the β1 integrin function and then activating the EGFR-Vav2-Rac1 pathway, finally resulting in apoptosis within 12–48 h exposure. The present study provides a novel insight regarding the potential role of Nox-driven ROS in QNs-induced arthropathy. - Highlights: ► Ofloxacin induces Nox2-driven ROS in encapsulated chondrocyte at 12–48 h. ► Ofloxacin stimulates ROS production via

  4. Plant stanols induce intestinal tumor formation by up-regulating Wnt and EGFR signaling in Apc Min mice.

    Science.gov (United States)

    Marttinen, Maija; Päivärinta, Essi; Storvik, Markus; Huikko, Laura; Luoma-Halkola, Heli; Piironen, Vieno; Pajari, Anne-Maria; Mutanen, Marja

    2013-01-01

    The rate of APC mutations in the intestine increases in middle-age. At the same period of life, plant sterol and stanol enriched functional foods are introduced to diet to lower blood cholesterol. This study examined the effect of plant stanol enriched diet on intestinal adenoma formation in the Apc(Min) mouse. Apc(Min) mice were fed 0.8% plant stanol diet or control diet for nine weeks. Cholesterol, plant sterols and plant stanols were analyzed from the caecum content and the intestinal mucosa. Levels of β-catenin, cyclin D1, epidermal growth factor receptor (EGFR) and extracellular signal-regulated kinase 1/2 (ERK1/2) were measured from the intestinal mucosa by Western blotting. Gene expression was determined from the intestinal mucosa using Affymetrix and the data were analyzed for enriched categories and pathways. Plant stanols induced adenoma formation in the small intestine, however, the adenoma size was not affected. We saw increased levels of nuclear β-catenin, phosphorylated β-catenin (Ser675 and Ser552), nuclear cyclin D1, total and phosphorylated EGFR and phosphorylated ERK1/2 in the intestinal mucosa after plant stanol feeding. The Affymetrix data demonstrate that several enzymes of cholesterol synthesis pathway were up-regulated, although the cholesterol level in the intestinal mucosa was not altered. We show that plant stanols induce adenoma formation by activating Wnt and EGFR signaling. EGFR signaling seems to have promoted β-catenin phosphorylation and its translocation into the nucleus, where the expression of cyclin D1 was increased. Up-regulated cholesterol synthesis may partly explain the increased EGFR signaling in the plant stanol-fed mice.

  5. Pan-HER - an antibody mixture targeting EGFR, HER2, and HER3 abrogates preformed and ligand-induced EGFR homo- and heterodimers

    DEFF Research Database (Denmark)

    Ellebaek, Sofie; Pedersen, Susanne Brix; Grandal, Michael;

    2016-01-01

    with Pan-HER were investigated by in situ proximity ligation assay and co-immunoprecipitation, demonstrating that Pan-HER and the EGFR-targeting mAb mixture efficiently down-regulate basal EGFR homo- and heterodimerization in two tested cell lines, whereas single mAbs had limited effects. Pan...

  6. Mycoplasma pneumoniae modulates STAT3-STAT6/EGFR-FOXA2 signaling to induce overexpression of airway mucins.

    Science.gov (United States)

    Hao, Yonghua; Kuang, Zhizhou; Jing, Jia; Miao, Jinfeng; Mei, Li Yu; Lee, Ryan J; Kim, Susie; Choe, Shawn; Krause, Duncan C; Lau, Gee W

    2014-12-01

    Aberrant mucin secretion and accumulation in the airway lumen are clinical hallmarks associated with various lung diseases such as asthma, chronic obstructive pulmonary disease, and cystic fibrosis. Mycoplasma pneumoniae, long appreciated as one of the triggers of acute exacerbations of chronic pulmonary diseases, has recently been reported to promote excessive mucus secretion. However, the mechanism of mucin overproduction induced by M. pneumoniae remains unclear. This study aimed to determine the mechanism by which M. pneumoniae induces mucus hypersecretion by using M. pneumoniae infection of mouse lungs, human primary bronchial epithelial (NHBE) cells cultured at the air-liquid interface, and the conventionally cultured airway epithelial NCI-H292 cell line. We demonstrated that M. pneumoniae induced the expression of mucins MUC5AC and MUC5B by activating the STAT6-STAT3 and epidermal growth factor receptor (EGFR) signal pathways, which in turn downregulated FOXA2, a transcriptional repressor of mucin biosynthesis. The upstream stimuli of these pathways, including interleukin-4 (IL-4), IL-6, and IL-13, increased dramatically upon exposure to M. pneumoniae. Inhibition of the STAT6, STAT3, and EGFR signaling pathways significantly restored the expression of FOXA2 and attenuated the expression of airway mucins MUC5AC and MUC5B. Collectively, these studies demonstrated that M. pneumoniae induces airway mucus hypersecretion by modulating the STAT/EGFR-FOXA2 signaling pathways. PMID:25287927

  7. EGFR participates downstream of ERα in estradiol-17β-D-glucuronide-induced impairment of Abcc2 function in isolated rat hepatocyte couplets.

    Science.gov (United States)

    Barosso, Ismael R; Zucchetti, Andrés E; Miszczuk, Gisel S; Boaglio, Andrea C; Taborda, Diego R; Roma, Marcelo G; Crocenzi, Fernando A; Sánchez Pozzi, Enrique J

    2016-04-01

    Estradiol-17β-D-glucuronide (E17G) induces acute endocytic internalization of canalicular transporters, including multidrug resistance-associated protein 2 (Abcc2) in rat, generating cholestasis. Several proteins organized in at least two different signaling pathways are involved in E17G cholestasis: one pathway involves estrogen receptor alpha (ERα), Ca(2+)-dependent protein kinase C and p38-mitogen activated protein kinase, and the other pathway involves GPR30, PKA, phosphoinositide 3-kinase/AKT and extracellular signal-related kinase 1/2. EGF receptor (EGFR) can potentially participate in both pathways since it interacts with GPR30 and ERα. Hence, the aim of this study was to analyze the potential role of this receptor and its downstream effectors, members of the Src family kinases in E17G-induced cholestasis. In vitro, EGFR inhibition by Tyrphostin (Tyr), Cl-387785 or its knockdown with siRNA strongly prevented E17G-induced impairment of Abcc2 function and localization. Activation of EGFR was necessary but not sufficient to impair the canalicular transporter function, whereas the simultaneous activation of EGFR and GPR30 could impair Abcc2 transport. The protection of Tyr was not additive to that produced by the ERα inhibitor ICI neither with that produced by Src kinase inhibitors, suggesting that EGFR shared the signaling pathway of ERα and Src. Further analysis of ERα, EGFR and Src activations induced by E17G, demonstrated that ERα activation precedes that of EGFR and EGFR activation precedes that of Src. In conclusion, activation of EGFR is a key factor in the alteration of canalicular transporter function and localization induced by E17G and it occurs before that of Src and after that of ERα.

  8. Inflammatory cells′ role in acetic acid-induced colitis

    Directory of Open Access Journals (Sweden)

    Mohammad H Sanei

    2014-01-01

    Full Text Available Background: Free radicals are the known mechanisms responsible for inducing colitis with two origins: Inflammatory cells and tissues. Only the inflammatory cells can be controlled by corticosteroids. Our aim was to assess the importance of neutrophils as one of the inflammatory cells in inducing colitis and to evaluate the efficacy of corticosteroids in the treatment of inflammatory bowel disease (IBD. Materials and Methods: Thirty-six mice were divided into six groups of six mice each. Colitis was induced in three groups by exposing them to acetic acid through enema (group 1, ex vivo (group 3, and enema after immune suppression (group 5. Each group had one control group that was exposed to water injection instead of acetic acid. Tissue samples were evaluated and compared based on macroscopic damages and biochemical and pathological results. Results: Considering neutrophilic infiltration, there were significant differences between groups 1, 3, 5, and the control of group 1. Groups 3, 5, and their controls, and group 1 and the control of group 3 had significant differences in terms of goblet depletion. Based on tissue originated H 2 O 2 , we found significant differences between group 1 and its control and group 3, and also between groups 5 and the control of group 3. All the three groups were significantly different from their controls based on Ferric Reducing Ability of Plasma (FRAP and such differences were also seen between group 1 with two other groups. Conclusion: Neutrophils may not be the only cause of oxidation process in colitis, and also makes the effectiveness of corticosteroids in the treatment of this disease doubtful.

  9. Ultraviolet-B induced expression of hypoxia-inducible factor 1α,transferrin receptor through EGFR/PI3K/AKT/DEC1 pathway

    Institute of Scientific and Technical Information of China (English)

    LI Yanhua; BI Zhigang

    2007-01-01

    The aim of this research was to explore the effects and signaling pathway of ultraviolet-B (UVB) irradiation on the expression of hypoxia-inducible factor 1α (HIF-1α) and transferrin receptor (TfR).HIF-1α protein was measured by Western blot method.Expressions of epidermal growth factor receptor (EGFR),phosphor-EGF-R and TfR after UVB irradiation were determined with flow cytometry.After UVB irradiation,mRNA levels of HIF-1α and TfR were detected by real time-PCR.Results showed that compared with control groups,UVB was able to induce HIF1α and TfR protein expression in a dose- and time-dependent manner in HaCat cells (P < 0.05).TfR mRNA was expressed in a dose-dependent manner and reached a peak at the 8th hour in HaCat cells (P<0.05) whereas HIF-1α mRNA expression was not affected by UVB treatment (P>0.05).The EGFR/PI3K/AKT signaling pathway was required for the induction of HIF-lcx and TfR expression induced by UVB.UVB induced activation of EGFR in HaCat cells and EGFR regulated expression of TfR and HIF-1α.EGFR (-/-) MEF did not increase the HIF 1 expression following UVB irradiation (P>0.05).In contrast,EGFR (+/+) MEF strongly enhanced HIF 1α expression after UVB irradiation (P < 0.05).PD153035,a selective inhibitor of EGFR tyrosine kinase,inhibited the TfR protein expression in UVB-treated cells in a dose-dependent manner (P<0.05).PI3K inhibitors,LY294002 and wortmannin,inhibited HIF-1α and TfR expressions induced by UVB (P < 0.05).The DEC1 (-/-) Ha-Cat cells did not increase their TfR and HIF-1α expressions following UVB irradiation (P>0.05).In contrast,DEC1 (+/+) HaCat cells strongly enhanced TfR and HIF-1α protein expression after UVB irradiation (P<0.05).We conclude that UVB induces TfR and HIF-1α expressions via EGFR/PI3K/AKT/DEC1 signaling pathway.

  10. NOX4 mediates cytoprotective autophagy induced by the EGFR inhibitor erlotinib in head and neck cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Sobhakumari, Arya [Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA (United States); Department of Pathology, The University of Iowa, Iowa City, IA (United States); Schickling, Brandon M. [Department of Internal Medicine, The University of Iowa, Iowa City, IA (United States); Love-Homan, Laurie; Raeburn, Ayanna [Department of Pathology, The University of Iowa, Iowa City, IA (United States); Fletcher, Elise V.M. [Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA (United States); Department of Pathology, The University of Iowa, Iowa City, IA (United States); Case, Adam J. [Free Radical and Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, IA (United States); Domann, Frederick E. [Interdisciplinary Graduate Program in Human Toxicology, The University of Iowa, Iowa City, IA (United States); Department of Pathology, The University of Iowa, Iowa City, IA (United States); Free Radical and Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, IA (United States); Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics (UIHC), Iowa City, IA (United States); Miller, Francis J. [Department of Internal Medicine, The University of Iowa, Iowa City, IA (United States); Free Radical and Radiation Biology Program, Department of Radiation Oncology, The University of Iowa, Iowa City, IA (United States); Holden Comprehensive Cancer Center, University of Iowa Hospitals and Clinics (UIHC), Iowa City, IA (United States); and others

    2013-11-01

    Most head and neck squamous cell carcinomas (HNSCCs) overexpress epidermal growth factor receptor (EGFR) and EGFR inhibitors are routinely used in the treatment of HNSCC. However, many HNSCC tumors do not respond or become refractory to EGFR inhibitors. Autophagy, which is a stress-induced cellular self-degradation process, has been reported to reduce the efficacy of chemotherapy in various disease models. The purpose of this study is to determine if the efficacy of the EGFR inhibitor erlotinib is reduced by activation of autophagy via NOX4-mediated oxidative stress in HNSCC cells. Erlotinib induced the expression of the autophagy marker LC3B-II and autophagosome formation in FaDu and Cal-27 cells. Inhibition of autophagy by chloroquine and knockdown of autophagy pathway genes Beclin-1 and Atg5 sensitized both cell lines to erlotinib-induced cytotoxicity, suggesting that autophagy may serve as a protective mechanism. Treatment with catalase (CAT) and diphenylene iodonium (DPI) in the presence of erlotinib suppressed the increase in LC3B-II expression in FaDu and Cal-27 cells. Erlotinib increased NOX4 mRNA and protein expression by increasing its promoter activity and mRNA stability in FaDu cells. Knockdown of NOX4 using adenoviral siNOX4 partially suppressed erlotinib-induced LC3B-II expression, while overexpression of NOX4 increased expression of LC3B-II. These studies suggest that erlotinib may activate autophagy in HNSCC cells as a pro-survival mechanism, and NOX4 may play a role in mediating this effect. - Highlights: • Erlotinib increased LC3B-II and autophagosome formation in HNSCC cells. • Inhibition of autophagy sensitized HNSCC cells to erlotinib. • Erlotinib increased NOX4 promoter and 3′UTR luciferase activity. • Manipulating NOX4 decreases or increases autophagy.

  11. Nimotuzumab enhances temozolomide-induced growth suppression of glioma cells expressing mutant EGFR in vivo.

    Science.gov (United States)

    Nitta, Yusuke; Shimizu, Saki; Shishido-Hara, Yukiko; Suzuki, Kaori; Shiokawa, Yoshiaki; Nagane, Motoo

    2016-03-01

    A mutant form of epidermal growth factor receptor (EGFR), EGFRvIII, is common in glioblastoma (GBM) and confers enhanced tumorigenic activity and drug resistance. Nimotuzumab, an anti-EGFR antibody, has shown preclinical and clinical activity to GBM, but its specific activity against EGFRvIII has not been fully investigated. Human glioma U87MG or LNZ308 cells overexpressing either wild-type (wt) EGFR or EGFRvIII were treated with nimotuzumab, temozolomide, or both. Expression and phosphorylation status of molecules were determined by Western blot analysis. Methylation status of promoter region of O(6) -methylguanine-DNA methyltransferase (MGMT) was detected by methylation-specific PCR. Antitumor activity was tested using nude mice bearing either subcutaneous or intracerebral xenografts along with analyses of EGFR phosphorylation status, proliferation, apoptosis, and vessel density. Nimotuzumab treatment resulted in reduction of EGFRvIII tyrosine phosphorylation with a decrease in Akt phosphorylation that was greater than that of wtEGFR. Correspondingly, antitumor effects, growth suppression and survival elongation, were more significant in mice bearing either subcutaneous or intracerebral tumor expressing EGFRvIII than in those expressing wtEGFR. These effects were markedly increased when temozolomide was combined with nimotuzumab. The post-treatment recurrent brain tumors exhibited a decrease in expression of the mismatch repair (MMR) proteins, MSH6 and MLH1, but their methylated MGMT status did not changed. Nimotuzumab has in vivo antitumor activity against GBM, especially those expressing EGFRvIII, when combined with temozolomide. This could provide a basis for preselection of patients with GBM by EGFR status who might benefit from the nimotuzumab and temozolomide combination therapy. PMID:26778701

  12. Role of LPAR3, PKC and EGFR in LPA-induced cell migration in oral squamous carcinoma cells

    International Nuclear Information System (INIS)

    Oral squamous cell carcinoma is an aggressive neoplasm with serious morbidity and mortality, which typically spreads through local invasive growth. Lysophosphatidic acid (LPA) is involved in a number of biological processes, and may have a role in cancer cell migration and invasiveness. LPA is present in most tissues and can activate cells through six different LPA receptors (LPAR1-6). Although LPA is predominantly promigratory, some of the receptors may have antimigratory effects in certain cells. The signalling mechanisms of LPA are not fully understood, and in oral carcinoma cells the specific receptors and pathways involved in LPA-stimulated migration are unknown. The oral carcinoma cell lines E10, SCC-9, and D2 were investigated. Cell migration was studied in a scratch wound assay, and invasion was demonstrated in organotypic three dimensional co-cultures. Protein and mRNA expression of LPA receptors was studied with Western blotting and qRT-PCR. Activation of signalling proteins was examined with Western blotting and isoelectric focusing, and signalling mechanisms were further explored using pharmacological agents and siRNA directed at specific receptors and pathways. LPA stimulated cell migration in the two oral carcinoma cell lines E10 and SCC-9, but was slightly inhibitory in D2. The receptor expression profile and the effects of specific pharmacological antagonist and agonists indicated that LPA-stimulated cell migration was mediated through LPAR3 in E10 and SCC-9. Furthermore, in both these cell lines, the stimulation by LPA was dependent on PKC activity. However, while LPA induced transactivation of EGFR and the stimulated migration was blocked by EGFR inhibitors in E10 cells, LPA did not induce EGFR transactivation in SCC-9 cells. In D2 cells, LPA induced EGFR transactivation, but this was associated with slowing of a very high inherent migration rate in these cells. The results demonstrate LPA-stimulated migration in oral carcinoma cells through LPAR3

  13. Cytokines induce tight junction disassembly in airway cells via an EGFR-dependent MAPK/ERK1/2-pathway.

    Science.gov (United States)

    Petecchia, Loredana; Sabatini, Federica; Usai, Cesare; Caci, Emanuela; Varesio, Luigi; Rossi, Giovanni A

    2012-08-01

    Epithelial barrier permeability is altered in inflammatory respiratory disorders by a variety of noxious agents through modifications of the epithelial cell structure that possibly involve tight junction (TJ) organization. To evaluate in vitro whether pro-inflammatory cytokines involved in the pathogenesis of respiratory disorders could alter TJ organization and epithelial barrier integrity, and to characterize the signal transduction pathway involved Calu-3 airway epithelial cells were exposed to TNF-a, IL-4 and IFN-g to assess changes in: (a) TJ assembly, that is, occludin and zonula occludens (ZO)-1 expression and localization, evaluated by confocal microscopy; (b) apoptotic activity, quantified using terminal transferase deoxyuridine triphosphate nick-end labeling staining; (c) epithelial barrier integrity, detected as transmembrane electrical resistance and expressed as G(T) values; (d) epidermal growth factor receptor (EGFR)-dependent mitogenactivated protein (MAP) kinase (MAPK)/extracellular signal-regulated kinases (ERK)1/2 phosphorylation, assessed by western blotting. Exposure to cytokines for 48 h induced a noticeable downregulation of the TJ transmembrane proteins. The degree ZO-1 and occludin colocalization was 62±2% in control cultures and significantly decreased in the presence of TNF-a (47±3%), IL-4 (43±1%) and INF-g (35±3%). Although no apoptosis induction was detected following exposure to cytokines, changes in the epithelial barrier integrity were observed, with a significant enhancement in paracellular conductance. G(T) values were, respectively, 1.030±0.0, 1.300±0.04, 1.260±0.020 and 2.220±0.015 (mS/cm²)1000 in control cultures and in those exposed to TNF-a, IFN-g and IL-4. The involvement of EGFR-dependent MAPK/ERK1/2 signaling pathway in cytokine-induced damage was demonstrated by a significant increase in threonine/tyrosine phosphorylation of ERK1/2, already detectable after 5 min incubation. All these cytokine-induced changes were

  14. EGFR trans-activation by urotensin II receptor is mediated by β-arrestin recruitment and confers cardioprotection in pressure overload-induced cardiac hypertrophy.

    Science.gov (United States)

    Esposito, Giovanni; Perrino, Cinzia; Cannavo, Alessandro; Schiattarella, Gabriele G; Borgia, Francesco; Sannino, Anna; Pironti, Gianluigi; Gargiulo, Giuseppe; Di Serafino, Luigi; Franzone, Anna; Scudiero, Laura; Grieco, Paolo; Indolfi, Ciro; Chiariello, Massimo

    2011-06-01

    Urotensin II (UTII) and its seven trans-membrane receptor (UTR) are up-regulated in the heart under pathological conditions. Previous in vitro studies have shown that UTII trans-activates the epidermal growth factor receptor (EGFR), however, the role of such novel signalling pathway stimulated by UTII is currently unknown. In this study, we hypothesized that EGFR trans-activation by UTII might exert a protective effect in the overloaded heart. To test this hypothesis, we induced cardiac hypertrophy by transverse aortic constriction (TAC) in wild-type mice, and tested the effects of the UTII antagonist Urantide (UR) on cardiac function, structure, and EGFR trans-activation. After 7 days of pressure overload, UR treatment induced a rapid and significant impairment of cardiac function compared to vehicle. In UR-treated TAC mice, cardiac dysfunction was associated with reduced phosphorylation levels of the EGFR and extracellular-regulated kinase (ERK), increased apoptotic cell death and fibrosis. In vitro UTR stimulation induced membrane translocation of β-arrestin 1/2, EGFR phosphorylation/internalization, and ERK activation in HEK293 cells. Furthermore, UTII administration lowered apoptotic cell death induced by serum deprivation, as shown by reduced TUNEL/Annexin V staining and caspase 3 activation. Interestingly, UTII-mediated EGFR trans-activation could be prevented by UR treatment or knockdown of β-arrestin 1/2. Our data show, for the first time in vivo, a new UTR signalling pathway which is mediated by EGFR trans-activation, dependent by β-arrestin 1/2, promoting cell survival and cardioprotection.

  15. Ascochlorin suppresses TGF-β1-induced PAI-1 expression through the inhibition of phospho-EGFR in rat kidney fibroblast cells.

    Science.gov (United States)

    Cho, Hyun-Ji; Kang, Jeong-Han; Jeong, Ji-Hak; Jeong, Yun-Jeong; Park, Kwan-Kyu; Park, Yoon-Yub; Moon, Yong-Suk; Kim, Hong-Tae; Chung, Il-Kyung; Kim, Cheorl-Ho; Chang, Hyeun-Wook; Chang, Young-Chae

    2012-04-01

    Fibrosis is induced by the excessive and abnormal deposition of extracellular matrix (ECM) with various growth factors in tissues. Transforming growth factor-β1 (TGF-β1), the growth factor involved in fibrosis, modulates ECM synthesis and accumulation. TGF-β1 enhances the production of stimulators of ECM synthesis such as plasminogen activator inhibitor type 1 (PAI-1). As such, PAI-1 expression directly influences the proteolysis, invasion, and accumulation of ECM. It was shown in this study that ascochlorin, a prenylpenl antiobiotic, prevents the expression of profibrotic factors, such as PAI-1 and collagen type I, and that the TGF-β1-induced PAI-1 promoter activity is inhibited by ascochlorin. Ascochlorin abolishes the phosphorylation of the EGFR-MEK-ERK signaling pathway to regulate the TGF-β1-induced expression of PAI-1 without the inhibition of TβRII phosphorylation. Furthermore, the MEK inhibitor and EGFR siRNA block PAI-1 expression, and the Raf-1, MEK, and ERK signaling pathways for the regulation of PAI-1 expression. Ascochlorin suppresses the matrix metalloproteinases (MMPs) activity to activate the heparin-binding EGF-like growth factor (HB-EGF), to induce the phosphorylation of EGFR, and the MMPs inhibitor suppresses EGFR phosphorylation and the PAI-1 mRNA levels. These results suggest that ascochlorin prevents the expression of PAI-1 via the inhibition of an EGFR-dependent signal transduction pathway activated by MMPs.

  16. Wogonin inhibits the proliferation and invasion, and induces the apoptosis of HepG2 and Bel7402 HCC cells through NF‑κB/Bcl-2, EGFR and EGFR downstream ERK/AKT signaling.

    Science.gov (United States)

    Liu, Xiaodong; Tian, Shuo; Liu, Mei; Jian, Lingyan; Zhao, Limei

    2016-10-01

    The anticancer effects of the natural flavonoid, wogonin, have been reported. However, its molecular mechanisms of action have not yet been fully explored. In the present study, we aimed to examine the molecular mechanisms of action of wogonin and its effects on the biological behavior of the HepG2 and Bel7402 hepatocellular carcinoma (HCC) cell lines. We also examined the effects of wogonin on nuclear factor-κB (NF-κB)/Bcl-2 and epidermal growth factor receptor (EGFR) signaling, as well as on downstream pathways of EGFR, namely extracellular signal-regulated kinase (ERK)/AKT signaling. We found that treatment with wogonin inhibited the proliferation and invasion, and induced the apoptosis of the HepG2 and Bel7402 cells. In addition, treatment with wogonin decreased cyclin D1, cyclin E, CDK4/6, Bcl-2 and matrix metalloproteinase 2 (MMP2) expression, and promoted the cleavage of caspase-3 and caspase-9 in a concentration-dependent manner. Further experiments revealed that wogonin inhibited NF-κB/Bcl-2 signaling by decreasing the IκB and p65 phosphorylation levels. Wogonin also inhibited the activation of the EGFR (Tyr845) signaling pathway, and that of downstream pathways of EGFR, namely ERK/AKT/MMP2 signaling. The depletion of EGFR by siRNA partly abolished the inhibitory effects of wogonin on cyclin D1, MMP2 expression. On the whole, our our findings demonstrate that wogonin effectively suppresses the proliferation, invasion and survival of HCC cells through the modulation of the NF-κB and EGFR signaling pathways.

  17. Synergistic effect of radiation on colon carcinogenesis induced by methylazoxymethanol acetate in ACI/N rats

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Takuji; Morishita, Yukio; Kawamori, Toshihiko; Suzui, Masumi; Kojima, Toshihiro; Sugie, Shigeyuki; Mori, Hideki (Gifu Univ. (Japan). Faculty of Medicine)

    1993-10-01

    The effect on colon and liver carcinogenicity in rats of a single X-irradiation exposure given either before or after methylazoxymethanol (MAM) acetate was studied in ACI/N rats of both sexes. A single dose of X-irradiation (3 Gy) was administered either 3 months before or after three weekly s.c. injection of MAM acetate (25 mg/kg body weight). At 365 days after the start, the incidence and multiplicity of MAM acetate-induced intestinal tumors were enhanced by X-irradiation either prior to or after the MAM acetate treatment. In addition, X-irradiation before MAM acetate increased the incidence of hepatocellular foci in either sex. In females, X-irradiation either before or after MAM acetate exposure decreased intestinal tumorigenesis. These findings suggest an apparent synergism of these agents in intestinal carcinogenesis of male rats. (author).

  18. Simultaneous inhibition of epidermal growth factor receptor (EGFR) signaling and enhanced activation of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) receptor-mediated apoptosis induction by an scFv : sTRAIL fusion protein with specificity for human EGFR

    NARCIS (Netherlands)

    Bremer, E; Samplonius, DF; van Genne, L; Dijkstra, MH; Kroesen, BJ; de Leij, LFMH; Helfrich, W

    2005-01-01

    Epidermal growth factor receptor (EGFR) signaling inhibition by monoclonal antibodies and EGFR-specific tyrosine kinase inhibitors has shown clinical efficacy in cancer by restoring susceptibility of tumor cells to therapeutic apoptosis induction. Tumor necrosis factor-related apoptosis-inducing lig

  19. Cucurmosin induces apoptosis of BxPC-3 human pancreatic cancer cells via inactivation of the EGFR signaling pathway.

    Science.gov (United States)

    Zhang, Baoming; Huang, Heguang; Xie, Jieming; Xu, Chunsen; Chen, Minghuang; Wang, Congfei; Yang, Aiqin; Yin, Qiang

    2012-03-01

    Pancreatic cancer remains the fourth most common cause of cancer-related death in the United States. Potent therapeutic strategies are urgently needed for pancreatic cancer. Cucurmosin is a novel type 1 ribosome-inactivating protein (RIP) isolated from the sarcocarp of Cucurbita moschata (pumpkin). Due to its cytotoxicity, cucurmosin can inhibit tumor cell proliferation through induction of apoptosis on tumor cells, but the specific mechanism is still unclear. We explored the function of cucurmosin in BxPC-3 pancreatic cancer cells using multiple cellular and molecular approaches such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry, reverse transcription polymerase chain reaction (RT-PCR), Western blotting and transmission electron microscopy for observing typical changes and formation of apoptotic bodies. We found that cucurmosin inhibited the proliferation of BxPC-3 cells in a time- and dose-dependent manner, and increased the cell population in the G0-G1 phase. With increasing concentration of cucurmosin, the expression of EGFR, p-PI3K, Akt, p-Akt, mTOR, p-mTOR, P70S6K-α, p-P70S6K-α, 4E-BP1 and p-4E-BP1 at the protein level was decreased, whereas the expression of p-Bad and caspase-9 was elevated. However, the mRNA expression of EGFR did not change. These findings suggest that cucurmosin can down-regulate the expression of EGFR by targeting. Cucurmosin induces the apoptosis of BxPC-3 pancreatic cancer cells via the PI3K/Akt/mTOR signaling pathway.

  20. Parallel phase 1 clinical trials inthe US andin China:accelerating the test ofavitinib inlung cancer asa novel inhibitor selectively targeting mutated EGFR andovercoming T790M-induced resistance

    Institute of Scientific and Technical Information of China (English)

    Xiao Xu

    2015-01-01

    Avitinib, a new generation inhibitor of epidermal growth factor receptor (EGFR), was approved for clinical trial in both China and the United States, and the phase 1 trials were initiated in both countries in parallel. In the preclinical stud-ies, avitinib showed three novel features including (1) irreversibly bindingEGFR by forming a covalent bound with Cys 797 in the ATP-binding pocket, (2) sparing wild-typeEGFR, and (3) overcoming T790M-induced resistance. Avitinib is the ifrst China-developed novel EGFR inhibitor that has entered in global clinical trials, and will provide a precision targeted therapy for non-small cell lung cancer patients.

  1. Protective Effect of Dodonaea viscosa (L) Against Lead Acetate Induced Altered Glycoprotein Profiles in Rats

    OpenAIRE

    Sivanesan, D.; Selvi, A. V. Veera Thamarai; Bhakyaraj, R.; Arunachalam, T.

    2009-01-01

    The present study was undertaken to examine the inhibitory effect of crude leaves of Dodonaea viscosa (L) on lead acetate induced synthesis of glycoproteins and sialic acid in liver and plasma. Enhanced synthesis of glycoproteins (protein - bound hexose and protein - bound hexosamine) and sialic acid levels were found in liver and plasma of the lead acetate poisoned rats. Administration of crude leaves of D.viscosa (100 mg/100 g body weight P.O.) effectively suppressed the synthesis of glycop...

  2. Effect of Potent Ethyl Acetate Fraction of Stereospermum suaveolens Extract in Streptozotocin-Induced Diabetic Rats

    Directory of Open Access Journals (Sweden)

    T. Balasubramanian

    2012-01-01

    Full Text Available To evaluate the antihyperglycemic effect of ethyl acetate fraction of ethanol extract of Stereospermum suaveolens in streptozotocin-(STZ- induced diabetic rats by acute and subacute models. In this paper, various fractions of ethanol extract of Stereospermum suaveolens were prepared and their effects on blood glucose levels in STZ-induced diabetic rats were studied after a single oral administration (200?mg/kg. Administration of the ethyl acetate fraction at 200?mg/kg once daily for 14 days to STZ-induced diabetic rats was also carried out. The parameters such as the fasting blood glucose, hepatic glycogen content, and pancreatic antioxidant levels were monitored. In the acute study, the ethyl acetate fraction is the most potent in reducing the fasting serum glucose levels of the STZ-induced diabetic rats. The 14-day repeated oral administration of the ethyl acetate fraction significantly reduced the fasting blood glucose and pancreatic TBARS level and significantly increased the liver glycogen, pancreatic superoxide dismutase, and catalase activities as well as reduced glutathione levels. The histopathological studies during the subacute treatment have been shown to ameliorate the STZ-induced histological damage of pancreas. This paper concludes that the ethyl acetate fraction from ethanol extract of Stereospermum suaveolens possesses potent antihyperglycemic and antioxidant properties, thereby substantiating the use of plant in the indigenous system of medicine.

  3. Diagnosis of Exclusion: A Case Report of Probable Glatiramer Acetate-Induced Eosinophilic Myocarditis

    Directory of Open Access Journals (Sweden)

    Christopher J. Michaud

    2014-01-01

    Full Text Available Importance. Medication-induced eosinophilia is an acknowledged, often self-limiting occurrence. Glatiramer acetate, a biologic injection used in the management of relapsing-remitting multiple sclerosis, is widely regarded as a safe and effective medication and lists eosinophilia as an infrequent side effect in its package insert. Contrary to reports of transient, benign drug-induced eosinophilia, we describe a case of probable glatiramer acetate-induced eosinophilia that ultimately culminated in respiratory distress, shock, and eosinophilic myocarditis. Observations. A 59-year-old female was admitted to the hospital after routine outpatient labs revealed leukocytosis (43,000 cells/mm3 with pronounced hypereosinophilia (63%. This patient had been using glatiramer acetate without complication for over 10 years prior to admission. Leukocytosis and hypereosinophilia persisted as a myriad of diagnostic evaluations returned negative, ultimately leading to respiratory depression, shock, and myocarditis. Glatiramer acetate was held for the first time on day 6 of the hospital stay with subsequent resolution of leukocytosis, hypereosinophilia, respiratory distress, and shock. Conclusions and Relevance. Glatiramer acetate was probably the cause of this observed hypereosinophilia and the resulting complications. Reports of glatiramer-induced eosinophilia are rare, and few case reports regarding medication-induced hypereosinophilia describe the severe systemic manifestations seen in this patient.

  4. Acetate but not propionate induces oxidative stress in bakers' yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Semchyshyn, Halyna M; Abrat, Oleksandra B; Miedzobrodzki, Jacek; Inoue, Yoshiharu; Lushchak, Volodymyr I

    2011-01-01

    The influence of acetic and propionic acids on baker's yeast was investigated in order to expand our understanding of the effect of weak organic acid food preservatives on eukaryotic cells. Both acids decreased yeast survival in a concentration-dependent manner, but with different efficiencies. The acids inhibited the fluorescein efflux from yeast cells. The inhibition constant of fluorescein extrusion from cells treated with acetate was significantly lower in parental strain than in either PDR12 (ABC-transporter Pdr12p) or WAR1 (transcriptional factor of Pdr12p) defective mutants. The constants of inhibition by propionate were virtually the same in all strains used. Yeast exposure to acetate increased the level of oxidized proteins and the activity of antioxidant enzymes, while propionate did not change these parameters. This suggests that various mechanisms underlie the yeast toxicity by acetic and propionic acids. Our studies with mutant cells clearly indicated the involvement of Yap1p transcriptional regulator and de novo protein synthesis in superoxide dismutase up-regulation by acetate. The up-regulation of catalase was Yap1p independent. Yeast pre-incubation with low concentrations of H₂O₂ caused cellular cross-protection against high concentrations of acetate. The results are discussed from the point of view that acetate induces a prooxidant effect in vivo, whereas propionate does not. PMID:21605494

  5. Inflammatory myopathy and severe rhabdomyolysis induced by leuprolide acetate therapy for prostate cancer: a case report

    Directory of Open Access Journals (Sweden)

    Rohacek Martin

    2011-08-01

    Full Text Available Abstract Introduction Leuprolide acetate is a synthetic analog of gonadotropin-releasing hormone used for the treatment of prostate cancer. Its side effects are hot flashes, nausea, and fatigue. We report a case of a patient with proximal inflammatory myopathy accompanied by severe rhabdomyolysis and renal failure following the second application of leuprolide acetate. Drug withdrawal and steroid therapy resulted in remission within six weeks of the diagnosis. To the best of our knowledge, our case report describes the second case of leuprolide acetate-induced inflammatory myopathy and the first case of severe leuprolide acetate-induced rhabdomyolysis and renal failure in the literature. Case presentation A 64-year-old Swiss Caucasian man was admitted to the hospital because of progressive proximal muscle weakness, dyspnea, and oliguria. He had been treated twice with leuprolide acetate in monthly doses. We performed a muscle biopsy, which excluded other causes of myopathy. The patient's renal failure and rhabdomyolysis were treated with rehydration and steroid therapy. Conclusion The aim of our case report is to highlight the rare but severe side effects associated with leuprolide acetate therapy used to treat patients with inflammatory myopathy: severe rhabdomyolysis and renal failure.

  6. CRIPTO1 expression in EGFR-mutant NSCLC elicits intrinsic EGFR-inhibitor resistance.

    Science.gov (United States)

    Park, Kang-Seo; Raffeld, Mark; Moon, Yong Wha; Xi, Liqiang; Bianco, Caterina; Pham, Trung; Lee, Liam C; Mitsudomi, Tetsuya; Yatabe, Yasushi; Okamoto, Isamu; Subramaniam, Deepa; Mok, Tony; Rosell, Rafael; Luo, Ji; Salomon, David S; Wang, Yisong; Giaccone, Giuseppe

    2014-07-01

    The majority of non-small cell lung cancer (NSCLC) patients harbor EGFR-activating mutations that can be therapeutically targeted by EGFR tyrosine kinase inhibitors (EGFR-TKI), such as erlotinib and gefitinib. Unfortunately, a subset of patients with EGFR mutations are refractory to EGFR-TKIs. Resistance to EGFR inhibitors reportedly involves SRC activation and induction of epithelial-to-mesenchymal transition (EMT). Here, we have demonstrated that overexpression of CRIPTO1, an EGF-CFC protein family member, renders EGFR-TKI-sensitive and EGFR-mutated NSCLC cells resistant to erlotinib in culture and in murine xenograft models. Furthermore, tumors from NSCLC patients with EGFR-activating mutations that were intrinsically resistant to EGFR-TKIs expressed higher levels of CRIPTO1 compared with tumors from patients that were sensitive to EGFR-TKIs. Primary NSCLC cells derived from a patient with EGFR-mutated NSCLC that was intrinsically erlotinib resistant were CRIPTO1 positive, but gained erlotinib sensitivity upon loss of CRIPTO1 expression during culture. CRIPTO1 activated SRC and ZEB1 to promote EMT via microRNA-205 (miR-205) downregulation. While miR-205 depletion induced erlotinib resistance, miR-205 overexpression inhibited CRIPTO1-dependent ZEB1 and SRC activation, restoring erlotinib sensitivity. CRIPTO1-induced erlotinib resistance was directly mediated through SRC but not ZEB1; therefore, cotargeting EGFR and SRC synergistically attenuated growth of erlotinib-resistant, CRIPTO1-positive, EGFR-mutated NSCLC cells in vitro and in vivo, suggesting that this combination may overcome intrinsic EGFR-inhibitor resistance in patients with CRIPTO1-positive, EGFR-mutated NSCLC. PMID:24911146

  7. EGFR mediates astragaloside IV-induced Nrf2 activation to protect cortical neurons against in vitro ischemia/reperfusion damages

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Da-min [Department of Anesthesiology, Affiliated Yixing People' s Hospital, Jiangsu University, Yixing (China); Lu, Pei-Hua, E-mail: lphty1_1@163.com [Department of Medical Oncology, Wuxi People' s Hospital Affiliated to Nanjing Medical University, Wuxi (China); Zhang, Ke; Wang, Xiang [Department of Anesthesiology, Affiliated Yixing People' s Hospital, Jiangsu University, Yixing (China); Sun, Min [Department of General Surgery, Affiliated Yixing People' s Hospital, Jiangsu University, Yixing (China); Chen, Guo-Qian [Department of Clinical Laboratory, Wuxi People' s Hospital Affiliated to Nanjing Medical University, Wuxi (China); Wang, Qiong, E-mail: WangQiongprof1@126.com [Department of Clinical Laboratory, Wuxi People' s Hospital Affiliated to Nanjing Medical University, Wuxi (China)

    2015-02-13

    In this study, we tested the potential role of astragaloside IV (AS-IV) against oxygen and glucose deprivation/re-oxygenation (OGD/R)-induced damages in murine cortical neurons, and studied the associated signaling mechanisms. AS-IV exerted significant neuroprotective effects against OGD/R by reducing reactive oxygen species (ROS) accumulation, thereby attenuating oxidative stress and neuronal cell death. We found that AS-IV treatment in cortical neurons resulted in NF-E2-related factor 2 (Nrf2) signaling activation, evidenced by Nrf2 Ser-40 phosphorylation, and its nuclear localization, as well as transcription of antioxidant-responsive element (ARE)-regulated genes: heme oxygenase-1 (HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO-1) and sulphiredoxin 1 (SRXN-1). Knockdown of Nrf2 through lentiviral shRNAs prevented AS-IV-induced ARE genes transcription, and abolished its anti-oxidant and neuroprotective activities. Further, we discovered that AS-IV stimulated heparin-binding-epidermal growth factor (HB-EGF) release to trans-activate epidermal growth factor receptor (EGFR) in cortical neurons. Blockage or silencing EGFR prevented Nrf2 activation by AS-IV, thus inhibiting AS-IV-mediated anti-oxidant and neuroprotective activities against OGD/R. In summary, AS-IV protects cortical neurons against OGD/R damages through activating of EGFR-Nrf2 signaling. - Highlights: • Pre-treatment of astragaloside IV (AS-IV) protects murine cortical neurons from OGD/R. • AS-IV activates Nrf2-ARE signaling in murine cortical neurons. • Nrf2 is required for AS-IV-mediated anti-oxidant and neuroprotective activities. • AS-IV stimulates HB-EGF release to trans-activate EGFR in murine cortical neurons. • EGFR mediates AS-IV-induced Nrf2 activation and neuroprotection against OGD/R.

  8. Electron Impact Induced Reactions of Ethyl Acetate and Its Sulphur Analogues

    DEFF Research Database (Denmark)

    Egsgaard, Helge; Larsen, Elfinn; Carlsen, Lars

    1983-01-01

    The electron impact induced reactions of ethyl acetate and its sulphur analogues have been studied by application of collision activation mass spectrometry and isotopic labelling with H-2 and O-18. The [M-C2H4]+·, [M-CH3]+ and [M-H2O]+· were selected for detailed investigations.......The electron impact induced reactions of ethyl acetate and its sulphur analogues have been studied by application of collision activation mass spectrometry and isotopic labelling with H-2 and O-18. The [M-C2H4]+·, [M-CH3]+ and [M-H2O]+· were selected for detailed investigations....

  9. Activation of EGFR promotes squamous carcinoma SCC10A cell migration and invasion via inducing EMT-like phenotype change and MMP-9-mediated degradation of E-cadherin.

    Science.gov (United States)

    Zuo, Jian-Hong; Zhu, Wei; Li, Mao-Yu; Li, Xin-Hui; Yi, Hong; Zeng, Gu-Qing; Wan, Xun-Xun; He, Qiu-Yan; Li, Jian-Huang; Qu, Jia-Quan; Chen, Yu; Xiao, Zhi-Qiang

    2011-09-01

    EGFR is a potent stimulator of invasion and metastasis in head and neck squamous cell carcinomas (HNSCC). However, the mechanism by which EGFR may stimulate tumor cell invasion and metastasis still need to be elucidated. In this study, we showed that activation of EGFR by EGF in HNSCC cell line SCC10A enhanced cell migration and invasion, and induced loss of epitheloid phenotype in parallel with downregulation of E-cadherin and upregulation of N-cadherin and vimentin, indicating that EGFR promoted SCC10A cell migration and invasion possibly by an epithelial to mesenchymal transition (EMT)-like phenotype change. Interestingly, activation of EGFR by EGF induced production of matrix metalloproteinase-9 (MMP-9) and soluble E-cadherin (sE-cad), and knockdown of MMP-9 by siRNA inhibited sE-cad production induced by EGF in SCC10A. Moreover, both MMP-9 knockdown and E-cadherin overexpression inhibited cell migration and invasion induced by EGF in SCC10A. The results indicate that EGFR activation promoted cell migration and invasion through inducing MMP-9-mediated degradation of E-cadherin into sE-cad. Pharmacologic inhibition of EGFR, MEK, and PI3K kinase activity in SCC10A reduced phosphorylated levels of ERK-1/2 and AKT, production of MMP-9 and sE-cad, cell migration and invasion, and expressional changes of EMT markers (E-cadherin and N-cadherin) induced by EGF, indicating that EGFR activation promotes cell migration and invasion via ERK-1/2 and PI3K-regulated MMP-9/E-cadherin signaling pathways. Taken together, the data suggest that EGFR activation promotes HNSCC SCC10A cell migration and invasion by inducing EMT-like phenotype change and MMP-9-mediated degradation of E-cadherin into sE-cad related to activation of ERK-1/2 and PI3K signaling pathways.

  10. Hepatotoxicity induced by cyproterone acetate: A report of three cases

    Institute of Scientific and Technical Information of China (English)

    Ioanna Savidou; Melanie Deutsch; Aspasia S Soultati; Dimitrios Koudouras; Georgia Kafiri; Spyridon P Dourakis

    2006-01-01

    Cyproterone acetate (CPA) is a steroidal synthetic progestagen and anti-androgenic compound widely administered in prostate cancer which has been evidentially correlated with a severe hepatotoxic potency.Three male patients aged 78-83 years are presented, in whom severe hepatotoxic reactions emerged after CPA administration. Patients were treated with CPA at the doses of 200-300 mg/d for malignant prostate disease for 3-12 mo prior to the acute manifestation of the hepatic disease. Clinical features compatible with mixed hepatocellular and cholestatic liver disease including jaundice, white stools and dark urine, manifested in all three cases whereas encephalopathy and ascites were present in two of the patients. Other primary causes of hepatotoxicity (alcohol consumption and viral hepatitis)were also verified in two cases, and in those patients biopsy findings revealed the presence of cirrhotic lesions in liver parenchyma. Discontinuation of the therapeutic agent led to the amelioration of the clinical profile in all the patients whereas a patient died 40 d after hospital admission due to sepsis, despite acute liver disease improvement. The current article highlights the hepatotoxic potency of a widely administered therapeutic agent and illustrates the importance of clinical surveillance especially in patients with previous hepatic diseases. Three relevant cases are reported and a review of the published literature is made.

  11. Renal cortical hexokinase and pentose phosphate pathway activation through the EGFR/Akt signaling pathway in endotoxin-induced acute kidney injury.

    Science.gov (United States)

    Smith, Joshua A; Stallons, L Jay; Schnellmann, Rick G

    2014-08-15

    While disruption of energy production is an important contributor to renal injury, metabolic alterations in sepsis-induced AKI remain understudied. We assessed changes in renal cortical glycolytic metabolism in a mouse model of sepsis-induced AKI. A specific and rapid increase in hexokinase (HK) activity (∼2-fold) was observed 3 h after LPS exposure and maintained up to 18 h, in association with a decline in renal function as measured by blood urea nitrogen (BUN). LPS-induced HK activation occurred independently of HK isoform expression or mitochondrial localization. No other changes in glycolytic enzymes were observed. LPS-mediated HK activation was not sufficient to increase glycolytic flux as indicated by reduced or unchanged pyruvate and lactate levels in the renal cortex. LPS-induced HK activation was associated with increased glucose-6-phosphate dehydrogenase activity but not glycogen production. Mechanistically, LPS-induced HK activation was attenuated by pharmacological inhibitors of the EGF receptor (EGFR) and Akt, indicating that EGFR/phosphatidylinositol 3-kinase/Akt signaling is responsible. Our findings reveal LPS rapidly increases renal cortical HK activity in an EGFR- and Akt-dependent manner and that HK activation is linked to increased pentose phosphate pathway activity.

  12. Leuprolide acetate induces structural and functional recovery of injured spinal cord in rats

    Directory of Open Access Journals (Sweden)

    Carmen Díaz-Galindo

    2015-01-01

    Full Text Available Gonadotropin-releasing hormone (GnRH and its synthetic analog leuprolide acetate, a GnRH agonist, have neurotrophic properties. This study was designed to determine whether administration of leuprolide acetate can improve locomotor behavior, gait, micturition reflex, spinal cord morphology and the amount of microglia in the lesion epicenter after spinal cord injury in rats. Rats with spinal cord compression injury were administered leuprolide acetate or saline solution for 5 weeks. At the 5 th week, leuprolide acetate-treated rats showed locomotor activity recovery by 38%, had improvement in kinematic gait and exhibited voiding reflex recovery by 60%, as compared with the 1 st week. By contrast, saline solution-treated rats showed locomotor activity recovery only by 7%, but voiding reflex did not recover. More importantly, leuprolide acetate treatment reduced microglial immunological reaction and induced a trend towards greater area of white and gray matter in the spinal cord. Therefore, leuprolide acetate has great potential to repair spinal cord injury.

  13. Antihyperglycemic effect of Hypericum perforatum ethyl acetate extract on streptozotocin-induced diabetic rats

    Institute of Scientific and Technical Information of China (English)

    Arokiyaraj S; Balamurugan R; Augustian P

    2011-01-01

    Objective: To evaluate the antihyperglycemic activity of ethyl acetate extract of Hypericum perforatum (H. perforatum) in streptozotocin (STZ)-induced diabetic rats. Methods: Acute toxicity and oral glucose tolerance test were performed in normal rats. Male albino rats were rendered diabetic by STZ (40 mg/kg, intraperitoneally). H. perforatum ethyl acetate extract was orally administered to diabetic rats at 50, 100 and 200 mg/kg doses for 15 days to determine the antihyperglycemic activity. Biochemical parameters were determined at the end of the treatment.Results: H. perforatum ethyl acetate extract showed dose dependant fall in fasting blood glucose (FBG). After 30 min of extract administration, FBG was reduced significantly when compared with normal rats. H. perforatum ethyl acetate extract produced significant reduction in plasma glucose level, serum total cholesterol, triglycerides, glucose-6-phosphatase levels. Tissue glycogen content, HDL-cholesterol, glucose-6-phosphate dehydrogenase were significantly increased compared with diabetic control. No death or lethal effect was observed in the toxic study.Conclusions:The results demonstrate that H. perforatum ethyl acetate extract possesses potent antihyperglycemic activity in STZ induced diabetic rats.

  14. Change in serum KL-6 level from baseline is useful for predicting life-threatening EGFR-TKIs induced interstitial lung disease

    OpenAIRE

    Hamada Hironobu; Miyoshi Seigo; Isobe Takeshi; Furonaka Osamu; Fujitaka Kazunori; Horimasu Yasushi; Ishikawa Nobuhisa; Hattori Noboru; Kawase Shigeo; Yamane Takashi; Yokoyama Akihito; Kohno Nobuoki

    2011-01-01

    Abstract Background A high incidence of interstitial lung disease (ILD) has been reported in patients with advanced non-small cell lung cancer (NSCLC) treated with epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), particularly in Japanese populations. A previous report from our laboratory demonstrated that KL-6 was a useful serum biomarker to assess the severity of drug-induced pneumonitis. Based on these observations, this study was conducted to evaluate the risk facto...

  15. Requirement of ERα and basal activities of EGFR and Src kinase in Cd-induced activation of MAPK/ERK pathway in human breast cancer MCF-7 cells

    Energy Technology Data Exchange (ETDEWEB)

    Song, Xiulong, E-mail: songxiulong@hotmail.com; Wei, Zhengxi; Shaikh, Zahir A., E-mail: zshaikh@uri.edu

    2015-08-15

    Cadmium (Cd) is a common environmental toxicant and an established carcinogen. Epidemiological studies implicate Cd with human breast cancer. Low micromolar concentrations of Cd promote proliferation of human breast cancer cells in vitro. The growth promotion of breast cancer cells is associated with the activation of MAPK/ERK pathway. This study explores the mechanism of Cd-induced activation of MAPK/ERK pathway. Specifically, the role of cell surface receptors ERα, EGFR, and Src kinase was evaluated in human breast cancer MCF-7 cells treated with 1–3 μM Cd. The activation of ERK was studied using a serum response element (SRE) luciferase reporter assay. Receptor phosphorylation was detected by Western blot analyses. Cd treatment increased both the SRE reporter activity and ERK1/2 phosphorylation in a concentration-dependent manner. Cd treatment had no effect on reactive oxygen species (ROS) generation. Also, blocking the entry of Cd into the cells with manganese did not diminish Cd-induced activation of MAPK/ERK. These results suggest that the effect of Cd was likely not caused by intracellular ROS generation, but through interaction with the membrane receptors. While Cd did not appear to activate either EGFR or Src kinase, their inhibition completely blocked the Cd-induced activation of ERK as well as cell proliferation. Similarly, silencing ERα with siRNA or use of ERα antagonist blocked the effects of Cd. Based on these results, it is concluded that not only ERα, but also basal activities of EGFR and Src kinase are essential for Cd-induced signal transduction and activation of MAPK/ERK pathway for breast cancer cell proliferation. - Highlights: • Low micromolar concentrations of Cd rapidly activate ERK1/2 in MCF-7 cells. • Signal transduction and resulting cell proliferation require EGFR, ERα, and Src. • These findings implicate Cd in promotion of breast cancer.

  16. Healing Acceleration of Acetic Acid-induced Colitis by Marigold (Calendula officinalis) in Male Rats

    OpenAIRE

    Nader Tanideh; Akram Jamshidzadeh; Masood Sepehrimanesh; Masood Hosseinzadeh; Omid Koohi-Hosseinabadi; Asma Najibi; Mozhdeh Raam; Sajad Daneshi; Seyedeh-Leili Asadi-Yousefabad

    2016-01-01

    Background/Aim: Ulcerative colitis (UC) is a type of chronic inflammatory bowel disease with unknown etiology. Several therapeutic strategies such as consumption of medicinal plants have been used for its treatment. The aim of this study was to evaluate healing effects of Calendula officinalis hydroalcoholic extract in experimentally induced UC in rat. Materials and Methods: Ninety-six rats, weighing 200 ± 20 g, were randomly divided into eight equal groups. UC induced by 3% acetic acid and o...

  17. Exogenous Ghrelin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats.

    Science.gov (United States)

    Matuszyk, Aleksandra; Ceranowicz, Piotr; Warzecha, Zygmunt; Cieszkowski, Jakub; Ceranowicz, Dagmara; Gałązka, Krystyna; Bonior, Joanna; Jaworek, Jolanta; Bartuś, Krzysztof; Gil, Krzysztof; Olszanecki, Rafał; Dembiński, Artur

    2016-01-01

    Previous studies have shown that ghrelin reduces colonic inflammation induced by trinitrobenzene sulfonic acid and dextran sodium sulfate. In the present study we determined the effect of treatment with ghrelin on the course of acetic acid-induced colitis in rats. Rectal administration of 3% acetic acid solution led to induction of colitis in all animals. Damage of the colonic wall was accompanied by an increase in mucosal concentration of pro-inflammatory interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), as well mucosal activity of myeloperoxidase. Moreover, induction of colitis led to a reduction in colonic blood flow and DNA synthesis. Administration of ghrelin after induction of colitis led to faster regeneration of the colonic wall and reduction in colonic levels of IL-1β, TNF-α, and myeloperoxidase. In addition, treatment with ghrelin improved mucosal DNA synthesis and blood flow. Our study disclosed that ghrelin exhibits a strong anti-inflammatory and healing effect in acetic acid-induced colitis. Our current observation in association with previous findings that ghrelin exhibits curative effect in trinitrobenzene sulfonic acid- and dextran sodium sulfate-induced colitis suggest that therapeutic effect of ghrelin in the colon is universal and independent of the primary cause of colitis. PMID:27598133

  18. Acetate supplementation as a means of inducing glioblastoma stem-like cell growth arrest.

    Science.gov (United States)

    Long, Patrick M; Tighe, Scott W; Driscoll, Heather E; Fortner, Karen A; Viapiano, Mariano S; Jaworski, Diane M

    2015-08-01

    Glioblastoma (GBM), the most common primary adult malignant brain tumor, is associated with a poor prognosis due, in part, to tumor recurrence mediated by chemotherapy and radiation resistant glioma stem-like cells (GSCs). The metabolic and epigenetic state of GSCs differs from their non-GSC counterparts, with GSCs exhibiting greater glycolytic metabolism and global hypoacetylation. However, little attention has been focused on the potential use of acetate supplementation as a therapeutic approach. N-acetyl-l-aspartate (NAA), the primary storage form of brain acetate, and aspartoacylase (ASPA), the enzyme responsible for NAA catalysis, are significantly reduced in GBM tumors. We recently demonstrated that NAA supplementation is not an appropriate therapeutic approach since it increases GSC proliferation and pursued an alternative acetate source. The FDA approved food additive Triacetin (glyceryl triacetate, GTA) has been safely used for acetate supplementation therapy in Canavan disease, a leukodystrophy due to ASPA mutation. This study characterized the effects of GTA on the proliferation and differentiation of six primary GBM-derived GSCs relative to established U87 and U251 GBM cell lines, normal human cerebral cortical astrocytes, and murine neural stem cells. GTA reduced proliferation of GSCs greater than established GBM lines. Moreover, GTA reduced growth of the more aggressive mesenchymal GSCs greater than proneural GSCs. Although sodium acetate induced a dose-dependent reduction of GSC growth, it also reduced cell viability. GTA-mediated growth inhibition was not associated with differentiation, but increased protein acetylation. These data suggest that GTA-mediated acetate supplementation is a novel therapeutic strategy to inhibit GSC growth.

  19. The role of MAPK signalling pathways in acetic acid-induced cell death of Saccharomyces cerevisiae

    OpenAIRE

    Azevedo, Flávio Humberto Torres Dias Feio de

    2011-01-01

    Dissertação de mestrado em Genética Molecular Mitogenic Activated Protein Kinase (MAPK) cascades are important signalling pathways that allow yeast cells to swiftly adapt to changing environmental conditions. Previous studies suggested that the High Osmolarity Glycerol (HOG) MAPK pathway and ceramide production are involved in acetic-acid induced apoptosis in yeast. Evidence that changes in the levels of endogenous ceramides can affect yeast cell fate has also been put forth...

  20. Drug-Induced Liver Injury by Glatiramer Acetate Used for Treatment of Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Attila Onmez

    2013-12-01

    Full Text Available Glatiramer acetate (GA, Copaxone is an approved drug for the treatment of relapsing–remitting multiple sclerosis. Most common side effects observed with GA are local injection site reactions, which can include pain, swelling, or redness. However, systemic adverse event such as hepatotoxicity related to GA is rarely seen. In this report, we present a case of GA-induced toxic hepatitis associated with cholestatic and hepatocellular damage.

  1. EGF/EGFR 调控 MMP-2在腺样囊性癌中的表达%The Study of EGF/EGFR Induced MMP-2 Expression in Adenoid Cystic Carcinoma

    Institute of Scientific and Technical Information of China (English)

    高杨; 张明; 宫春梅

    2015-01-01

    [ ABSTRACT] Objective To research the regulation of matrix metalloproteinases-2( MMP-2) in adenoid cystic carcinoma which in-duced by EGF/EGFR,and to further explore the mechanisms of the MMP-2 in occurrence,development and metastasis of the adenoid cystic carcinoma.Methods First of all immunohistochemistry was used to observe the expression and distribute of EGFR and MMP-2 in the normal salivary gland and adenoid cystic carcinoma;the real time RT-PCR was used to observe the expression of MMP-2 mRNA in adenoid cystic carcinoma induced by different doses of EGF,then we analysized the expression of MMP-2 mRNA induced by EGF which acted by EGFR in-hibitor;at the last we observed that EGF induced the expression of MMP-2 protein in adenoid cystic carcinoma by western blot.Results Im-munohistochemistry showed that EGFR and MMP-2 have the positive expressions in adenoid cystic carcinoma,while have the negative expres-sions in normal salivary gland;the real time RT-PCR showed that EGF can increase the expression of MMP-2 in adenoid cystic carcinoma,es-pecially in 20μg/L.It also was found that EGFR inhibitor can suppress the increased expression of MMP-2 induced by EGF.The western blot was used to verify that the expression of MMP-2 protein in adenoid cystic carcinoma was induced by EGF.Conclusion The expression of MMP-2 in adenoid cystic carcinoma was induced by EGF,the new theoretical guidance was taken to the clinical treatment of adenoid cystic carcinoma.%目的:通过研究表皮生长因子及其受体(EGF/EGFR)调控基质金属蛋白酶-2(MMP-2)在腺样囊性癌细胞中的表达,为进一步探讨MMP-2在腺样囊性癌发生、发展、转移过程的机制奠定基础。方法应用免疫组织化学SP法检测正常涎腺及腺样囊性癌组织中EGFR和MMP-2的表达分布情况;利用定时定量RT-PCR法检测不同剂量的EGF调控MMP-2 mRNA在腺样囊性癌细胞中的表达水平,分析EGFR阻断剂作用下EGF调控MMP-2 mRNA的表

  2. A review of the treatment options for skin rash induced by EGFR-targeted therapies: Evidence from randomized clinical trials and a meta-analysis

    International Nuclear Information System (INIS)

    Agents targeting the epidermal growth factor receptor (EGFR) are amongst the most extensively used of the targeted agents in the therapy of some of the most common solid tumors. Although they avoid many of the classic side effects associated with cytotoxic chemotherapy, they are associated with unpleasant cutaneous toxicities which can affect treatment compliance and impinge on patient quality of life. To date, despite a plethora of consensus recommendations, expert opinions and reviews, there is a paucity of evidence-based guidance for the management of the skin rash that occurs in the treatment of patients receiving EGFR-targeted therapies. A literature search was conducted as a first step towards investigating not only an evidence-based approach to the management of skin rash, but also with a view to designing future randomized trials. The literature search identified seven randomized trials and a meta-analysis was conducted using the data from four of these trials involving oral antibiotics. The meta-analysis of the data from these four trials suggests that prophylactic antibiotics might reduce the relative risk of severe rash associated with EGFR-targeted agents by 42–77%. Vitamin K cream was also identified as having a potential role in the management EGFR-targeted agent induced rash. This review and meta-analysis clearly identify the need for further randomized studies of the role of oral antibiotics in this setting. The results of the ongoing randomized trials of the topical application of vitamin K cream plus or minus doxycycline and employing prophylactic versus reactive strategies are eagerly awaited

  3. Obestatin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats

    Directory of Open Access Journals (Sweden)

    Aleksandra Matuszyk

    2016-01-01

    Full Text Available Obestatin, a 23-amino acid peptide derived from the proghrelin, has been shown to exhibit some protective and therapeutic effects in the gut. The aim of present study was to determine the effect of obestatin administration on the course of acetic acid-induced colitis in rats. Materials and Methods. Studies have been performed on male Wistar rats. Colitis was induced by a rectal enema with 3.5% acetic acid solution. Obestatin was administered intraperitoneally twice a day at a dose of 8 nmol/kg, starting 24 h after the induction of colitis. Seven or 14 days after the induction of colitis, the healing rate of the colon was evaluated. Results. Treatment with obestatin after induction of colitis accelerated the healing of colonic wall damage and this effect was associated with a decrease in the colitis-evoked increase in mucosal activity of myeloperoxidase and content of interleukin-1β. Moreover, obestatin administration significantly reversed the colitis-evoked decrease in mucosal blood flow and DNA synthesis. Conclusion. Administration of exogenous obestatin exhibits therapeutic effects in the course of acetic acid-induced colitis and this effect is related, at least in part, to the obestatin-evoked anti-inflammatory effect, an improvement of local blood flow, and an increase in cell proliferation in colonic mucosa.

  4. Obestatin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats.

    Science.gov (United States)

    Matuszyk, Aleksandra; Ceranowicz, Piotr; Warzecha, Zygmunt; Cieszkowski, Jakub; Bonior, Joanna; Jaworek, Jolanta; Kuśnierz-Cabala, Beata; Konturek, Peter; Ambroży, Tadeusz; Dembiński, Artur

    2016-01-01

    Obestatin, a 23-amino acid peptide derived from the proghrelin, has been shown to exhibit some protective and therapeutic effects in the gut. The aim of present study was to determine the effect of obestatin administration on the course of acetic acid-induced colitis in rats. Materials and Methods. Studies have been performed on male Wistar rats. Colitis was induced by a rectal enema with 3.5% acetic acid solution. Obestatin was administered intraperitoneally twice a day at a dose of 8 nmol/kg, starting 24 h after the induction of colitis. Seven or 14 days after the induction of colitis, the healing rate of the colon was evaluated. Results. Treatment with obestatin after induction of colitis accelerated the healing of colonic wall damage and this effect was associated with a decrease in the colitis-evoked increase in mucosal activity of myeloperoxidase and content of interleukin-1β. Moreover, obestatin administration significantly reversed the colitis-evoked decrease in mucosal blood flow and DNA synthesis. Conclusion. Administration of exogenous obestatin exhibits therapeutic effects in the course of acetic acid-induced colitis and this effect is related, at least in part, to the obestatin-evoked anti-inflammatory effect, an improvement of local blood flow, and an increase in cell proliferation in colonic mucosa.

  5. Investigation of metabolic changes in STZ-induced diabetic rats with hyperpolarized [1-13C]acetate

    DEFF Research Database (Denmark)

    Koellisch, Ulrich; Laustsen, Christoffer; Nørlinger, Thomas S;

    2015-01-01

    In the metabolism of acetate several enzymes are involved, which play an important role in free fatty acid oxidation. Fatty acid metabolism is altered in diabetes patients and therefore acetate might serve as a marker for pathological changes in the fuel selection of cells, as these changes occur...... in diabetes patients. Acetylcarnitine is a metabolic product of acetate, which enables its transport into the mitochondria for energy production. This study investigates whether the ratio of acetylcarnitine to acetate, measured by noninvasive hyperpolarized [1-(13)C]acetate magnetic resonance spectroscopy......, could serve as a marker for myocardial, hepatic, and renal metabolic changes in rats with Streptozotocin (STZ)-induced diabetes in vivo. We demonstrate that the conversion of acetate to acetylcarnitine could be detected and quantified in all three organs of interest. More interestingly, we found...

  6. Transcript and metabolite alterations increase ganoderic acid content in Ganoderma lucidum using acetic acid as an inducer.

    Science.gov (United States)

    Ren, Ang; Li, Xiong-Biao; Miao, Zhi-Gang; Shi, Liang; Jaing, Ai-Liang; Zhao, Ming-Wen

    2014-12-01

    Acetic acid at 5-8 mM increased ganoderic acid (GA) accumulation in Ganoderma lucidum. After optimization by the response surface methodology, the GA content reached 5.5/100 mg dry weight, an increase of 105% compared with the control. The intermediate metabolites of GA biosynthesis, lanosterol and squalene also increased to 47 and 15.8 μg/g dry weight, respectively, in response to acetic acid. Acetic acid significantly induced transcription levels of sqs, lano, hmgs and cyp51 in the GA biosynthesis pathway. An acetic acid-unregulated acetyl coenzyme A synthase (acs) gene was selected from ten candidate homologous acs genes. The results indicate that acetic acid alters the expression of genes related to acetic acid assimilation and increases GA biosynthesis and the metabolic levels of lanosterol, squalene and GA-a, thereby resulting in GA accumulation. PMID:25216642

  7. Haemato-biochemical alterations induced by lead acetate toxicity in wistar rats

    Directory of Open Access Journals (Sweden)

    S. G. Suradkar

    Full Text Available An experiment was conducted to study the haemato-biochemical alterations induced by lead acetate toxicity in 48 Wistar rats of either sex, divided uniformly into four different groups. The rats of group I received only deionised water as control while, group II, III and IV were given lead acetate @ 1 PPM, 100 PPM and 1000 PPM, in drinking deionised water respectively for 28 days. In group III and IV dose dependant significant (P<0.05 reductions in TEC, Hb, PCV and TLC were observed. No significant change was observed in neutrophil, eosinophil, basophil and monocyte count in any treatment groups, whereas the lymphocyte count decreased significantly (P<0.05 in group III and IV. A dose dependant significant (P<0.05 increase in AST, ALP, AKP, GGT, BUN and creatinine was experiential while TP and albumin levels were decreased in group III and IV. [Vet World 2009; 2(11.000: 429-431

  8. Red Palm Oil Attenuates Lead Acetate Induced Testicular Damage in Adult Male Sprague-Dawley Rats

    Directory of Open Access Journals (Sweden)

    A. I. Jegede

    2015-01-01

    Full Text Available To study the protective effect of Red Palm Oil (RPO on testicular damage induced by administration of lead acetate on male Sprague-Dawley rats, 28 rats divided into four groups of 7 animals each were used. They were administered orally with RPO (1 mL and 2 mL and lead acetate (i.p. 6 mg/kg body weight/day, respectively. Treatment was conducted for 8 weeks, and 24 hrs after the last treatment the rats were sacrificed using cervical dislocation. Sperms collected from epididymis were used for seminal fluid analyses; while the testes sample was used for ROS and oxidative enzyme activities assessment. Statistical analysis was carried out using GraphPad Prism 5.02 statistical analysis package. Administration of lead acetate increased generation of reactive oxygen species (ROS significantly (p<0.05 as evidenced by the elevated value of H2O2 and LPO and decreased GSH level. Also there was reduced epididymal sperm count, poor grade of sperm motility, and lower percentage of normal sperm morphology significantly. Coadministration with RPO, however, has a protective effect against lead toxicity by decreasing H2O2 production, increased GSH level, and increased sperm qualities especially. This shows that RPO has a potential to attenuate the toxic effect of lead on testicular cells preventing possible resultant male infertility.

  9. Red Palm Oil Attenuates Lead Acetate Induced Testicular Damage in Adult Male Sprague-Dawley Rats

    Science.gov (United States)

    Jegede, A. I.; Offor, U.; Azu, O. O.; Akinloye, O.

    2015-01-01

    To study the protective effect of Red Palm Oil (RPO) on testicular damage induced by administration of lead acetate on male Sprague-Dawley rats, 28 rats divided into four groups of 7 animals each were used. They were administered orally with RPO (1 mL and 2 mL) and lead acetate (i.p.) 6 mg/kg body weight/day, respectively. Treatment was conducted for 8 weeks, and 24 hrs after the last treatment the rats were sacrificed using cervical dislocation. Sperms collected from epididymis were used for seminal fluid analyses; while the testes sample was used for ROS and oxidative enzyme activities assessment. Statistical analysis was carried out using GraphPad Prism 5.02 statistical analysis package. Administration of lead acetate increased generation of reactive oxygen species (ROS) significantly (p < 0.05) as evidenced by the elevated value of H2O2 and LPO and decreased GSH level. Also there was reduced epididymal sperm count, poor grade of sperm motility, and lower percentage of normal sperm morphology significantly. Coadministration with RPO, however, has a protective effect against lead toxicity by decreasing H2O2 production, increased GSH level, and increased sperm qualities especially. This shows that RPO has a potential to attenuate the toxic effect of lead on testicular cells preventing possible resultant male infertility. PMID:26516332

  10. The relative expression of Mig6 and EGFR is associated with resistance to EGFR kinase inhibitors.

    Directory of Open Access Journals (Sweden)

    Xiaofei Chang

    Full Text Available The sensitivity of only a few tumors to anti-epidermal growth factor receptor EGFR tyrosine kinase inhibitors (TKIs can be explained by the presence of EGFR tyrosine kinase (TK domain mutations. In addition, such mutations were rarely found in tumor types other than lung, such as pancreatic and head and neck cancer. In this study we sought to elucidate mechanisms of resistance to EGFR-targeted therapies in tumors that do not harbor TK sensitizing mutations in order to identify markers capable of guiding the decision to incorporate these drugs into chemotherapeutic regimens. Here we show that EGFR activity was markedly decreased during the evolution of resistance to the EGFR tyrosine kinase inhibitor (TKI erlotinib, with a concomitant increase of mitogen-inducible gene 6 (Mig6, a negative regulator of EGFR through the upregulation of the PI3K-AKT pathway. EGFR activity, which was more accurately predicted by the ratio of Mig6/EGFR, highly correlated with erlotinib sensitivity in panels of cancer cell lines of different tissue origins. Blinded testing and analysis in a prospectively followed cohort of lung cancer patients treated with gefitinib alone demonstrated higher response rates and a marked increased in progression free survival for patients with a low Mig6/EGFR ratio (approximately 100 days, P = 0.01.

  11. Up-regulation of fatty acid synthase induced by EGFR/ERK activation promotes tumor growth in pancreatic cancer

    Energy Technology Data Exchange (ETDEWEB)

    Bian, Yong, E-mail: drbiany@126.com [Department of Science and Technology, Nanjing University of Chinese Medicine, 210023 (China); Yu, Yun [College of Pharmacy, Nanjing University of Chinese Medicine, 210023 (China); Wang, Shanshan; Li, Lin [Department of Science and Technology, Nanjing University of Chinese Medicine, 210023 (China)

    2015-08-07

    Lipid metabolism is dysregulated in many human diseases including atherosclerosis, type 2 diabetes and cancers. Fatty acid synthase (FASN), a key lipogenic enzyme involved in de novo lipid biosynthesis, is significantly upregulated in multiple types of human cancers and associates with tumor progression. However, limited data is available to understand underlying biological functions and clinical significance of overexpressed FASN in pancreatic ductal adenocarcinoma (PDAC). Here, upregulated FASN was more frequently observed in PDAC tissues compared with normal pancreas in a tissue microarray. Kaplan–Meier survival analysis revealed that high expression level of FASN resulted in a significantly poor prognosis of PDAC patients. Knockdown or inhibition of endogenous FASN decreased cell proliferation and increased cell apoptosis in HPAC and AsPC-1 cells. Furthermore, we demonstrated that EGFR/ERK signaling accounts for elevated FASN expression in PDAC as ascertained by performing siRNA assays and using specific pharmacological inhibitors. Collectively, our results indicate that FASN exhibits important roles in tumor growth and EGFR/ERK pathway is responsible for upregulated expression of FASN in PDAC. - Highlights: • Increased expression of FASN indicates a poor prognosis in PDAC. • Elevated FASN favors tumor growth in PDAC in vitro. • Activation of EGFR signaling contributes to elevated FASN expression.

  12. Up-regulation of fatty acid synthase induced by EGFR/ERK activation promotes tumor growth in pancreatic cancer

    International Nuclear Information System (INIS)

    Lipid metabolism is dysregulated in many human diseases including atherosclerosis, type 2 diabetes and cancers. Fatty acid synthase (FASN), a key lipogenic enzyme involved in de novo lipid biosynthesis, is significantly upregulated in multiple types of human cancers and associates with tumor progression. However, limited data is available to understand underlying biological functions and clinical significance of overexpressed FASN in pancreatic ductal adenocarcinoma (PDAC). Here, upregulated FASN was more frequently observed in PDAC tissues compared with normal pancreas in a tissue microarray. Kaplan–Meier survival analysis revealed that high expression level of FASN resulted in a significantly poor prognosis of PDAC patients. Knockdown or inhibition of endogenous FASN decreased cell proliferation and increased cell apoptosis in HPAC and AsPC-1 cells. Furthermore, we demonstrated that EGFR/ERK signaling accounts for elevated FASN expression in PDAC as ascertained by performing siRNA assays and using specific pharmacological inhibitors. Collectively, our results indicate that FASN exhibits important roles in tumor growth and EGFR/ERK pathway is responsible for upregulated expression of FASN in PDAC. - Highlights: • Increased expression of FASN indicates a poor prognosis in PDAC. • Elevated FASN favors tumor growth in PDAC in vitro. • Activation of EGFR signaling contributes to elevated FASN expression

  13. Silica nanoparticles induce cytokine responses in lung epithelial cells through activation of a p38/TACE/TGF-α/EGFR-pathway and NF-κΒ signalling

    Energy Technology Data Exchange (ETDEWEB)

    Skuland, Tonje, E-mail: tonje.skuland@fhi.no; Øvrevik, Johan; Låg, Marit; Schwarze, Per; Refsnes, Magne

    2014-08-15

    Amorphous silica nanoparticles (SiNPs) have previously been shown to induce marked cytokine (interleukin-6; IL-6 and interleukin-8; CXCL8/IL-8) responses independently of particle uptake in human bronchial epithelial BEAS-2B cells. In this study the involvement of the mitogen-activated protein kinases (MAP-kinases), nuclear factor-kappa Β (NF-κΒ) and in particular tumour necrosis factor-α converting enzyme (TACE) and—epidermal growth factor receptor (EGFR) signalling pathways were examined in triggering of IL-6 and CXCL8 release after exposure to a 50 nm silica nanoparticle (Si50). Exposure to Si50 increased phosphorylation of NF-κΒ p65 and MAP-kinases p38 and JUN-N-terminal protein kinase pathways (JNK), but not extracellular signal regulated kinases (ERK). Inhibition of NF-κΒ and p38 reduced the cytokine responses to Si50, whereas neither JNK- nor ERK-inhibition exerted any significant effect on the responses to Si50. Increases in membrane-bound transforming growth factor-α (TGF-α) release and EGFR phosphorylation were also observed after Si50 exposure, and pre-treatment with inhibitors of these pathways reduced the release of IL-6 and CXCL8, but did not affect the Si50-induced phosphorylation of p38 and p65. In contrast, p38-inhibition partially reduced Si50-induced TGF-α release, while the p65-inhibition was without effect. Overall, our results indicate that Si50-induced IL-6 and CXCL8 responses in BEAS-2B cells were regulated through combined activation of several pathways, including NF-κΒ and p38/TACE/TGF-α/EGFR signalling. The study identifies critical, initial events in the triggering of pro-inflammatory responses by nanoparticles. - Highlights: • Silica nanoparticles induce IL-6 and CXCL8 via NFκB and MAPKinase p38 in BEAS-2B • Silica nanoparticles induce release of the EGF-receptor ligand TGF-α • TGF-α release contributes to the IL-6 and CXCL8 release • Phosphorylation of p38 is involved in release of TGF-α.

  14. EGFR-targeted plasmonic magnetic nanoparticles suppress lung tumor growth by abrogating G2/M cell-cycle arrest and inducing DNA damage

    Directory of Open Access Journals (Sweden)

    Kuroda S

    2014-08-01

    Full Text Available Shinji Kuroda,1 Justina Tam,2 Jack A Roth,1 Konstantin Sokolov,2 Rajagopal Ramesh3–5 1Department of Thoracic and Cardiovascular Surgery, 2Department of Imaging Physics, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; 3Department of Pathology, 4Graduate Program in Biomedical Sciences, 5Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA Background: We have previously demonstrated the epidermal growth factor receptor (EGFR-targeted hybrid plasmonic magnetic nanoparticles (225-NP produce a therapeutic effect in human lung cancer cell lines in vitro. In the present study, we investigated the molecular mechanism of 225-NP-mediated antitumor activity both in vitro and in vivo using the EGFR-mutant HCC827 cell line. Methods: The growth inhibitory effect of 225-NP on lung tumor cells was determined by cell viability and cell-cycle analysis. Protein expression related to autophagy, apoptosis, and DNA-damage were determined by Western blotting and immunofluorescence. An in vivo efficacy study was conducted using a human lung tumor xenograft mouse model. Results: The 225-NP treatment markedly reduced tumor cell viability at 72 hours compared with the cell viability in control treatment groups. Cell-cycle analysis showed the percentage of cells in the G2/M phase was reduced when treated with 225-NP, with a concomitant increase in the number of cells in Sub-G1 phase, indicative of cell death. Western blotting showed LC3B and PARP cleavage, indicating 225-NP-treatment activated both autophagy- and apoptosis-mediated cell death. The 225-NP strongly induced γH2AX and phosphorylated histone H3, markers indicative of DNA damage and mitosis, respectively. Additionally, significant γH2AX foci formation was observed in 225-NP-treated cells compared with control treatment groups, suggesting 225-NP induced cell death by triggering DNA damage. The 225-NP-mediated DNA damage involved abrogation of the

  15. 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...

  16. Evaluation of Mango Byproduct Extracts as Antioxidant Against Pb-Acetate-Induced Oxidative Stress and Genotoxicity in Mice

    Directory of Open Access Journals (Sweden)

    Makawy Aida I. El

    2015-03-01

    Full Text Available The antioxidant and antiproliferative properties of mango by-products were investigated. This study was carried out to evaluate the protective role of mango peel or kernel defatted extracts against Pb-acetate adverse effects on oxidant/antioxidant status, liver dysfunction biomarkers, histopathological changes and genotoxicity in male mice. Total phenolic content and antioxidant activity of both extracts were evaluated. Two doses of both extracts (50 and 100 mg/kg were used to evaluate their role against the toxicity of Pb-acetate (500 ppm. Mice given mango extracts with Pb-acetate had significantly lower plasma MDA, AST and ALT and higher glutathione than mice given Pb-acetate alone. Mango extracts prevented the histopathological changes in liver induced by Pb-acetate and decreased the cytotoxicity of lead by increasing the ratio of PCE/NCE. Mango extract treatment reduced the DNA damage induced by Pb-acetate in liver as demonstrated by a reduction in micronuclei and decrease in tail length, tail DNA% and Olive tail moment. It can be concluded that mango by-product extracts have potential to protect from oxidative stress and genotoxicity of lead.

  17. Punicalagin Mollifies Lead Acetate-Induced Oxidative Imbalance in Male Reproductive System

    Science.gov (United States)

    Rao, Faiza; Zhai, Yiwen; Sun, Fei

    2016-01-01

    Punicalagin (PU) is a known antioxidant. The present study examined PU to protect against lead-induced oxidative stress (OS) testicular damage in mice. Significant increase in lipid peroxidation (LPO) after intraperitoneal injection of lead acetate (LA) indicated enormous generation of reactive oxygen species (ROS). Lead-induced OS has a direct effect on the differentiation of spermatogonial cells, showing a significant decline in sperm count. Supplementation of PU significantly changes values of LPO and glutathione (GSH) with a concomitant increase in sperm count, a marked decrease in the abnormal sperms, and a decline in the morphologically abnormal sperm population. Moreover, the histopathological evaluation of testes and epididymides showed severe changes in mice treated with LA. PU significantly induced nuclear factor erythroid-2 related factor 2-like 2 (Nrf2) expression and phase II enzymes, and data suggest that PU may inhibit OS through Nrf2 activation. The fertility test proved that PU might play an important role in male infertility treatment, especially in the type of infertility induced by OS. PMID:27529221

  18. Silver nanoparticles impede phorbol myristate acetate-induced monocyte-macrophage differentiation and autophagy

    Science.gov (United States)

    Xu, Yingying; Wang, Liming; Bai, Ru; Zhang, Tianlu; Chen, Chunying

    2015-09-01

    Monocytes/macrophages are important constituents of the innate immune system. Monocyte-macrophage differentiation is not only crucial for innate immune responses, but is also related to some cardiovascular diseases. Silver nanoparticles (AgNPs) are one of the most widely used nanomaterials because of their broad-spectrum antimicrobial properties. However, the effect of AgNPs on the functions of blood monocytes is scarcely reported. Here, we report the impedance effect of AgNPs on THP-1 monocyte differentiation, and that this effect was mediated by autophagy blockade and lysosomal impairment. Firstly, AgNPs inhibit phorbol 12-myristate 13-acetate (PMA)-induced monocyte differentiation by down-regulating both expression of surface marker CD11b and response to lipopolysaccharide (LPS) stimulation. Secondly, autophagy is activated during PMA-induced THP-1 monocyte differentiation, and the autophagy inhibitor chloroquine (CQ) can inhibit this process. Thirdly, AgNPs block the degradation of the autophagy substrate p62 and induce autophagosome accumulation, which demonstrates the blockade of autophagic flux. Fourthly, lysosomal impairments including alkalization and decrease of lysosomal membrane stability were observed in AgNP-treated THP-1 cells. In conclusion, we demonstrate that the impedance of monocyte-macrophage differentiation by AgNPs is mediated by autophagy blockade and lysosomal dysfunction. Our results suggest that crosstalk exists in different biological effects induced by AgNPs.

  19. Tannic acid alleviates lead acetate-induced neurochemical perturbations in rat brain.

    Science.gov (United States)

    Ashafaq, Mohammad; Tabassum, Heena; Vishnoi, Shruti; Salman, Mohd; Raisuddin, Sheikh; Parvez, Suhel

    2016-03-23

    Oxidative stress has been projected as a promising mechanism involved in lead exposure. The lead predisposition catalyzes oxidative reactions and generates reactive oxygen species. The present study was carried out to investigate the effect of oral administration of tannic acid (TA) on behavioral deficit, antioxidative deterioration induced by lead acetate (LA) exposure on experimental rat brain. Male Wistar rats were treated with 50mg/kg body weight of LA and TA for three times a week for two weeks. Our data showed LA-induced profound elevation of ROS production and oxidative stress, as evidenced by increased levels of oxidative stress markers such as lipid peroxidation and protein carbonyl observed in LA treated rats, whereas significant depletion in the activity of non-enzymatic antioxidants, enzymatic antioxidants, neurotoxicity biomarker and histological changes were observed in LA treated rat brain. However, TA administration restored antioxidant status of brain significantly when compared to control. Our results demonstrate that TA exhibits potent antioxidant properties and suppresses oxidative damages in rat brain induced by LA treatment. These findings were further supported by the neurotoxicity biomarker and histopathological findings in the brain tissue showed that TA protected tissue from deleterious effects of LA exposure. It is concluded, these data suggest that LA induces oxidative stress and supplementation of TA has a powerful antioxidant effect, and it protected rat brain from poisonous effect of LA exposure in experimental rat.

  20. Alisol B acetate induces apoptosis of SGC7901 cells via mitochondrial and phosphatidylinositol 3-kinases/Akt signaling pathways

    Institute of Scientific and Technical Information of China (English)

    Yong-Hong Xu; Li-Jie Zhao; Yan Li

    2009-01-01

    AIM: To examine the effect of alisol B acetate on the growth of human gastric cancer cell line SGC7901 and its possible mechanism of action. METHODS: The cytotoxic effect of alisol B acetate on SGC7901 cells was measured by 3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Phase-contrast and electron microscopy were used to observe the morphological changes. Cell cycle and mitochondrial transmembrane potential (ΔΨm) were determined by flow cytometry. Western blotting was used to detect the expression of apoptosis-regulated gene Bcl-2, Bax, Apaf-1, caspase-3, caspase-9, Akt, P-Akt and phosphatidylinositol 3-kinases (PI3K). RESULTS: Alisol B acetate inhibited the proliferation of SGC7901 cell line in a time- and dose-dependent manner. PI staining showed that alisol B acetate can change the cell cycle distribution of SGC7901, increase the proportion of cells in G0-G1 phase and decrease the proportion of S phase cells and G2-M phase cells. Alisol B acetate at a concentration of 30 μmol/L induced apoptosis after 24, 48 and 72 h incubation, with occurrence rates of apoptotic cells of 4.36%, 14.42% and 21.16%, respectively. Phase-contrast and electron microscopy revealed that the nuclear fragmentation and chromosomal condensed, cells shrank and attachment loss appeared in the SGC7901 treated with alisol B acetate. Apoptosis of SGC7901 with alisol B acetate. Apoptosis of SGC7901 cells was associated with cell cycle arrest, caspase-3 and caspase-9 activation, loss of mitochondrial membrane potential and up-regulation of the ratio of Bax/Bcl-2 and inhibition of the PI3K/Akt. CONCLUSION: Alisol B acetate exhibits an antiproliferative effect in SGC7901 cells by inducing apoptosis. Apoptosis of SGC7901 cells involves mitochondria-caspase and PI3K/Akt dependent pathways.

  1. DLC-1 induces mitochondrial apoptosis and epithelial mesenchymal transition arrest in nasopharyngeal carcinoma by targeting EGFR/Akt/NF-κB pathway.

    Science.gov (United States)

    Huang, Wei; Liu, Jie; Feng, Xiangling; Chen, Huan; Zeng, Liang; Huang, Guoling; Liu, Weidong; Wang, Lei; Jia, Wei; Chen, Jiawen; Ren, Caiping

    2015-04-01

    Loss of deleted in liver cancer-1 (DLC-1) can induce apoptosis and inhibit the mobility, migration and metastasis in several cancers. Previously, we revealed that ectopic expression of DLC-1 can suppress proliferation, mobility, migration and tumorigenesis in nasopharyngeal carcinoma (NPC). However, the molecular mechanisms accounting for the roles of DLC-1 in NPC are still obscure. In the present work, we attempted to study and uncover the mechanisms underlying the functions of DLC-1 in NPC. The apoptosis of 5-8F-DLC-1 cells, established previously, was analyzed by mitochondrial membrane potentials assay and flow cytometer analysis. And the antibodies involving pathways such as mitochondrial-associated apoptosis, epithelial mesenchymal transition and metastasis were applied to detect and compare the expression level of targeted proteins. The obvious apoptosis of 5-8F-DLC-1 cells was observed reflected by mitochondrial depolarization and lower ratio in cell viability. Subsequently, the activation of mitochondrial apoptosis was verified by the increased expressions of Bax, Apaf1, cleave-caspases and cleave-PARP, etc, and the decreased expressions of Bcl-2, Bcl-xL, Mcl-1, Survivin, etc, in 5-8F-DLC-1 cells. Then, the inhibited epithelial mesenchymal transition of 5-8F-DLC-1 cells was validated by upregulated expression of E-cadherin and downregulated expression of N-cadherin, Snail, Vimentin. Subsequently, downregulated expressions of proteins such as FAK, RhoA, ROCK1 and cdc25 related to cell adhesion and cytoskeleton organization were also observed. And expressions of MMPs were inhibited in 5-8F-DLC-1 cells. At last, the inhibited activity of EGFR/Akt/NF-κB axis was revealed by the decreased expressions of phosho-EGFR, phosho-Akt, phosho-p38MAPK, phosho-IKKα and phosho-p65. Here, we systematically explored the mechanisms underlying the negative roles of DLC-1 in NPC cells. For the first time, we confirmed that the ectopic expression DLC-1 can induce mitochondrial

  2. Multiple genetic control of acetate-induced olfactory responses in Drosophila melanogaster larvae.

    Science.gov (United States)

    Cobb, M; Dannet, F

    1994-10-01

    Behavioural responses of Drosophila melanogaster larvae were measured in response to olfactory stimulation with an homologous series of eight aliphatic n-acetates (methyl ... octyl acetate) and with cis-vaccenyl acetate. Larvae tended to be attracted to short-chain acetates (methyl ... pentyl) and repelled by longer chain acetates (hexyl, heptyl and octyl acetate). All larvae were strongly attracted to propyl acetate, irrespective of the dose studied. Larval olfactory responses generally declined with age. Two geographical strains showed specific anosmias. Katsunuma (Japan) larvae showed no response to hexyl acetate; chromosome substitution showed this behaviour to be controlled by genes on chromosome II. Tai (Ivory Coast) larvae showed no response to pentyl acetate; chromosome substitution showed that two genetic factors were primarily involved, on the X chromosome and chromosome III. The response was modulated by chromosome II. No effect of the Y chromosome was found. Two olfactory mutants were studied, olfC (X chromosome) and Indf (chromosome III); both mutants showed abnormal responses to certain acetates. The results are discussed in terms of various models of olfactory processing and the implications of these models for the number of genes involved in olfaction. PMID:7989222

  3. The influence of pretreatment with ghrelin on the development of acetic-acid-induced colitis in rats.

    Science.gov (United States)

    Maduzia, D; Matuszyk, A; Ceranowicz, D; Warzecha, Z; Ceranowicz, P; Fyderek, K; Galazka, K; Dembinski, A

    2015-12-01

    Ghrelin has been primarily shown to exhibit protective and therapeutic effect in the gut. Pretreatment with ghrelin inhibits the development of acute pancreatitis and accelerates pancreatic recovery in the course of this disease. In the stomach, ghrelin reduces gastric mucosal damage induced by ethanol, stress or alendronate, as well as accelerates the healing of acetic acid-induced gastric and duodenal ulcer. The aim of present studies was to investigate the effect of pretreatment with ghrelin on the development of acetic acid-induced colitis. Studies have been performed on male Wistar rats. Animals were treated intraperitoneally with saline (control) or ghrelin (4, 8 or 16 nmol/kg/dose). Saline or ghrelin was given twice: 8 and 1 h before induction of colitis. Colitis was induced by a rectal enema with 1 ml of 4% solution of acetic acid and the severity of colitis was assessed 1 or 24 hours after induction of inflammation. Rectal administration of acetic acid induced colitis in all animals. Damage of colonic wall was seen at the macroscopic and microscopic level. This effect was accompanied by a reduction in colonic blood flow and mucosal DNA synthesis. Moreover, induction of colitis significantly increased mucosal concentration of pro-inflammatory interleukin-1β (IL-1β), activity of myeloperoxidase and concentration of malondialdehyde (MDA). Mucosal activity of superoxide dismutase (SOD) was reduced. Pretreatment with ghrelin reduced the area and grade of mucosal damage. This effect was accompanied by an improvement of blood flow, DNA synthesis and SOD activity in colonic mucosa. Moreover, ghrelin administration reduced mucosal concentration of IL-1β and MDA, as well as decreased mucosal activity of myeloperoxidase. Administration of ghrelin protects the large bowel against the development of the acetic acid-induced colitis and this effect seems to be related to the ghrelin-evoked anti-inflammatory and anti-oxidative effects.

  4. Biologically Induced Hydrogen Production Drives High Rate/High Efficiency Microbial Electrosynthesis of Acetate from Carbon Dioxide

    NARCIS (Netherlands)

    Jourdin, Ludovic; Lu, Yang; Flexer, Victoria; Keller, Jurg; Freguia, Stefano

    2016-01-01

    Electron-transfer pathways occurring in biocathodes are still unknown. We demonstrate here that high rates of acetate production by microbial electrosynthesis are mainly driven by an electron flux from the electrode to carbon dioxide, occurring via biologically induced hydrogen, with (99±1)% elec

  5. Aliphatic acetogenin constituents of avocado fruits inhibit human oral cancer cell proliferation by targeting the EGFR/RAS/RAF/MEK/ERK1/2 pathway

    Energy Technology Data Exchange (ETDEWEB)

    D' Ambrosio, Steven M. [Department of Radiology, College of Medicine, The Ohio State University, Columbus, OH 43210 (United States); Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210 (United States); Han, Chunhua [Department of Radiology, College of Medicine, The Ohio State University, Columbus, OH 43210 (United States); Pan, Li; Douglas Kinghorn, A. [Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210 (United States); Ding, Haiming, E-mail: ding.29@osu.edu [Department of Radiology, College of Medicine, The Ohio State University, Columbus, OH 43210 (United States)

    2011-06-10

    Highlights: {yields} The aliphatic acetogenins [(2S,4S)-2,4-dihydroxyheptadec-16-enyl acetate] (1) and [(2S,4S)-2,4-dihydroxyheptadec-16-ynyl acetate] (2) isolated from avocado fruit inhibit phosphorylation of c-RAF (Ser338) and ERK1/2 (Thr202/Tyr204). {yields} Aliphatic acetogenin 2, but not 1, prevents EGF-induced activation of EGFR (Tyr1173). {yields} Combination of both aliphatic acetogenins synergistically inhibits c-RAF (Ser338) and ERK1/2 (Thr202/Tyr204) phosphorylation and human oral cancer cell proliferation. {yields} The potential anticancer activity of avocado fruits is due to a combination of specific aliphatic acetogenins targeting two key components of the EGFR/RAS/RAF/MEK/ERK1/2 cancer pathway. {yields} Providing a double hit on a critical cancer pathway such as EGFR/RAS/RAF/MEK/ERK1/2 by phytochemicals like those found in avocado fruit could lead to more effective approach toward cancer prevention. -- Abstract: Avocado (Persea americana) fruits are consumed as part of the human diet and extracts have shown growth inhibitory effects in various types of human cancer cells, although the effectiveness of individual components and their underlying mechanism are poorly understood. Using activity-guided fractionation of the flesh of avocado fruits, a chloroform-soluble extract (D003) was identified that exhibited high efficacy towards premalignant and malignant human oral cancer cell lines. From this extract, two aliphatic acetogenins of previously known structure were isolated, compounds 1 [(2S,4S)-2,4-dihydroxyheptadec-16-enyl acetate] and 2 [(2S,4S)-2,4-dihydroxyheptadec-16-ynyl acetate]. In this study, we show for the first time that the growth inhibitory efficacy of this chloroform extract is due to blocking the phosphorylation of EGFR (Tyr1173), c-RAF (Ser338), and ERK1/2 (Thr202/Tyr204) in the EGFR/RAS/RAF/MEK/ERK1/2 cancer pathway. Compounds 1 and 2 both inhibited phosphorylation of c-RAF (Ser338) and ERK1/2 (Thr202/Tyr204). Compound 2, but not

  6. Aliphatic acetogenin constituents of avocado fruits inhibit human oral cancer cell proliferation by targeting the EGFR/RAS/RAF/MEK/ERK1/2 pathway

    International Nuclear Information System (INIS)

    Highlights: → The aliphatic acetogenins [(2S,4S)-2,4-dihydroxyheptadec-16-enyl acetate] (1) and [(2S,4S)-2,4-dihydroxyheptadec-16-ynyl acetate] (2) isolated from avocado fruit inhibit phosphorylation of c-RAF (Ser338) and ERK1/2 (Thr202/Tyr204). → Aliphatic acetogenin 2, but not 1, prevents EGF-induced activation of EGFR (Tyr1173). → Combination of both aliphatic acetogenins synergistically inhibits c-RAF (Ser338) and ERK1/2 (Thr202/Tyr204) phosphorylation and human oral cancer cell proliferation. → The potential anticancer activity of avocado fruits is due to a combination of specific aliphatic acetogenins targeting two key components of the EGFR/RAS/RAF/MEK/ERK1/2 cancer pathway. → Providing a double hit on a critical cancer pathway such as EGFR/RAS/RAF/MEK/ERK1/2 by phytochemicals like those found in avocado fruit could lead to more effective approach toward cancer prevention. -- Abstract: Avocado (Persea americana) fruits are consumed as part of the human diet and extracts have shown growth inhibitory effects in various types of human cancer cells, although the effectiveness of individual components and their underlying mechanism are poorly understood. Using activity-guided fractionation of the flesh of avocado fruits, a chloroform-soluble extract (D003) was identified that exhibited high efficacy towards premalignant and malignant human oral cancer cell lines. From this extract, two aliphatic acetogenins of previously known structure were isolated, compounds 1 [(2S,4S)-2,4-dihydroxyheptadec-16-enyl acetate] and 2 [(2S,4S)-2,4-dihydroxyheptadec-16-ynyl acetate]. In this study, we show for the first time that the growth inhibitory efficacy of this chloroform extract is due to blocking the phosphorylation of EGFR (Tyr1173), c-RAF (Ser338), and ERK1/2 (Thr202/Tyr204) in the EGFR/RAS/RAF/MEK/ERK1/2 cancer pathway. Compounds 1 and 2 both inhibited phosphorylation of c-RAF (Ser338) and ERK1/2 (Thr202/Tyr204). Compound 2, but not compound 1, prevented EGF-induced

  7. Developmental lead acetate exposure induces embryonic toxicity and memory deficit in adult zebrafish.

    Science.gov (United States)

    Chen, Jiangfei; Chen, Yuanhong; Liu, Wei; Bai, Chenglian; Liu, Xuexia; Liu, Kai; Li, Rong; Zhu, Jian-Hong; Huang, Changjiang

    2012-01-01

    Lead is a persistent metal and commonly present in our living environment. The present study was aimed to investigate lead-induced embryonic toxicity, behavioral responses, and adult learning/memory deficit in zebrafish. Lead acetate (PbAc) induced malformations such as uninflated swim bladder, bent spine and yolk-sac edema with an EC₅₀ of 0.29 mg/L at 120 h post fertilization (hpf). Spontaneous movement as characterized by tail bend frequency was significantly altered in zebrafish embryos following exposure to PbAc. Behavior assessment demonstrated that lead exposure changed behavioral responses in zebrafish larvae, as hyperactivity was detected within the first minute of light-to-dark transition in the fish exposed to PbAc from 6 to 96 hpf, and a different dose-dependent change was found in swimming speeds in the dark and in the light at 120 hpf following lead exposure. Learning/memory task assay showed that embryos exposed to PbAc from 6 to 120 hpf developed learning/memory deficit at adulthood as exhibited by a significant decrease in accuracy rate to find the food and a significant increase in finding time. Overall, our results suggested that low dose of developmental lead exposure resulted in embryonic toxicity, behavioral alteration, and adult learning/memory deficit in zebrafish. PMID:22975620

  8. Protective Effect of Vitamins C and E on Depot-Medroxyprogesterone Acetate-Induced Ovarian Oxidative Stress In Vivo

    OpenAIRE

    Ismiyati, Atik; Wiyasa, I Wayan Arsana; Hidayati, Dwi Yuni Nur

    2016-01-01

    A study was designed to investigate ameliorates effect of combined vitamins C and E able to against depot-medroxyprogesterone acetate- (DMPA-) induced ovarian oxidative stress in rat. Twenty-five female Wistar rats were divided into the following groups (n=5 rats each): control (untreated) (C); depot-medroxyprogesterone acetate (DMPA); DMPA plus green vitamin C (at dose of 0.2 mg/gram; 0.4 mg/gram; 0.8 mg/gram) and vitamin E (0.04 IU/gram). The treatment with combined vitamins C and E was per...

  9. Protective Effect of Vitamins C and E on Depot-Medroxyprogesterone Acetate-Induced Ovarian Oxidative Stress In Vivo

    OpenAIRE

    Ismiyati, Atik; Wiyasa, I Wayan Arsana; Hidayati, Dwi Yuni Nur

    2016-01-01

    A study was designed to investigate ameliorates effect of combined vitamins C and E able to against depot-medroxyprogesterone acetate- (DMPA-) induced ovarian oxidative stress in rat. Twenty-five female Wistar rats were divided into the following groups (n = 5 rats each): control (untreated) (C); depot-medroxyprogesterone acetate (DMPA); DMPA plus green vitamin C (at dose of 0.2 mg/gram; 0.4 mg/gram; 0.8 mg/gram) and vitamin E (0.04 IU/gram). The treatment with combined vitamins C and E was p...

  10. Naringin ameliorates acetic acid induced colitis through modulation of endogenous oxido-nitrosative balance and DNA damage in rats

    OpenAIRE

    Kumar, Venkatashivam Shiva; Rajmane, Anuchandra Ramchandra; Adil, Mohammad; Kandhare, Amit Dattatraya; Ghosh, Pinaki; Bodhankar, Subhash Laxman

    2013-01-01

    The aim of this study was to evaluate the effect of naringin on experimentally induced inflammatory bowel disease in rats. Naringin (20, 40 and 80 mg/kg) was given orally for 7 days to Wistar rats before induction of colitis by intrarectal instillation of 2 mL of 4% (v/v) acetic acid solution. The degree of colonic mucosal damage was analyzed by examining mucosal damage, ulcer area, ulcer index and stool consistency. Intrarectal administration of 4% acetic acid resulted in significant modulat...

  11. Synergistic action of famotidine and chlorpheniramine on acetic acid-induced chronic gastric ulcer in rats

    Institute of Scientific and Technical Information of China (English)

    Zhen Qin; Chao Chen

    2005-01-01

    AIM: To assess the synergistic action of famotidine (FMD)and chlorpheniramine (CPA) on acetic acid-induced chronic gastric ulcer in rats.METHODS: Chronic gastric lesions were induced in male Sprague-Dawley (SD) rats by serosal application of the acetic acid. Forty SD rats were randomly divided into blank group (n = 8), control group (n = 8), FMD group (n= 8), CPA group (n = 8), and FMD+CPA group (n = 8).Each group was given intraperitoneally (i.p.) 0.5 mL/100g distilled water, 9 g/L NaCl saline, 4 mg/kg FMD, 10mg/kg CPA, 4 mg/kg FMD+10 mg/kg CPA, respectively,daily for 10 d. On d 10, ulcer area was determined by planimetry. The level of myeloperoxidase (MPO) in the liver homogenation was determined by biochemical methods and the plasma levels of 6-ketoprostaglandin F1 alpha (6-keto-PGF1a)and IL-8 were determined by radioimmunoassay.RESULTS: The synergistic effects of FMD+CPA group on the lesion, IL-8, 6-keto-PGF1a and MPO were confirmed.The effect of FMlD+CPA group was significantly different as compared to the control and FMD groups. The lesion (mm2) was reduced from 40.18±2.6 in control group to 6.83±2.97 in PMD+CPA group, P<0.01, and from 32.9±3.27 in FMD group to 6.83±2.97 in pMlD+CPA group,P<0.01. The plasma levels of IL-8 decreased from 0.69±0.11 ng/L in control group to 0.4±0.04 ng/L in PMD+CPA group, P<0.01, and from 0.51±0.08 ng/L in FMD group to 0.4±0.04 ng/L in PMD+CPA group, P<0.05. The level of 6-keto-PGF1a increased from 7.55±1.65 ng/L in control group to 16.62±0.97 ng/L in PMD+CPA group, P<0.01,and from 13.15±1.48 ng/L in FMD group to 16.62±0.97ng/L in PMD+CPA group, P<0.05. The levels of MPO in the liver homogenate decreased from 9.12±2.05 u/Lin control group to 4.33±0.95 u/L in PMD+CPA group,P<0.01, and from 8.3±1.29 u/L in FMD group to 4.33±0.95 u/L, P<0.01.CONCLUSION: The synergistic action of FMD and CPA on acetic acid-induced chronic gastric ulcer in rats decreases the incidence of ulcer and also enhances the

  12. Therapeutic effect of ethyl acetate extract from Asparagus cochinchinensis on phthalic anhydride-induced skin inflammation.

    Science.gov (United States)

    Sung, Ji-Eun; Lee, Hyun-Ah; Kim, Ji-Eun; Go, Jun; Seo, Eun-Ji; Yun, Woo-Bin; Kim, Dong-Seob; Son, Hong-Joo; Lee, Chung-Yeoul; Lee, Hee-Seob; Hwang, Dae-Youn

    2016-03-01

    Asparagus cochinchinensis has been used to treat various diseases including fever, cough, kidney disease, breast cancer, inflammatory disease and brain disease, while IL-4 cytokine has been considered as key regulator on the skin homeostasis and the predisposition toward allergic skin inflammation. However, few studies have investigated its effects and IL-4 correlation on skin inflammation to date. To quantitatively evaluate the suppressive effects of ethyl acetate extracts of A. cochinchinensis (EaEAC) on phthalic anhydride (PA)-induced skin inflammation and investigate the role of IL-4 during their action mechanism, alterations in general phenotype biomarkers and luciferase-derived signals were measured in IL-4/Luc/CNS-1 transgenic (Tg) mice with PA-induced skin inflammation after treatment with EaEAC for 2 weeks. Key phenotype markers including lymph node weight, immunoglobulin E (IgE) concentration, epidermis thickness and number of infiltrated mast cells were significantly decreased in the PA+EaEAC treated group compared with the PA+Vehicle treated group. In addition, expression of IL-1β and TNF-α was also decreased in the PA+EaEAC cotreated group, compared to PA+Vehicle treated group. Furthermore, a significant decrease in the luciferase signal derived from IL-4 promoter was detected in the abdominal region, submandibular lymph node and mesenteric lymph node of the PA+EaEAC treated group, compared to PA+Vehicle treated group. Taken together, these results suggest that EaEAC treatment could successfully improve PA-induced skin inflammation of IL-4/Luc/CNS-1 Tg mice, and that IL-4 cytokine plays a key role in the therapeutic process of EaEAC. PMID:27051441

  13. Healing acceleration of acetic acid-induced colitis by marigold (Calendula officinalis in male rats

    Directory of Open Access Journals (Sweden)

    Nader Tanideh

    2016-01-01

    Full Text Available Background/Aim: Ulcerative colitis (UC is a type of chronic inflammatory bowel disease with unknown etiology. Several therapeutic strategies such as consumption of medicinal plants have been used for its treatment. The aim of this study was to evaluate healing effects of Calendula officinalis hydroalcoholic extract in experimentally induced UC in rat. Materials and Methods: Ninety-six rats, weighing 200 ± 20 g, were randomly divided into eight equal groups. UC induced by 3% acetic acid and oral doses of C. officinalis extract, 1500 and 3000 mg/kg, and enema (gel 10% and 20% were given. Two groups as positive controls were given asacol (enema and oral mesalamine. Negative control groups were given normal saline and base gel. On days 3 and 7, intestinal histopathology and weight changes, plus oxidative stress indices including malondialdehyde (MDA level and myeloperoxidase (MPO activity were assayed. Results: A significant increase in the body weight of rats was seen in the group given C. officinalis extract 3000 mg/kg orally, oral mesalamine, and 20% intracolonic gel form of marigold extract compared with negative control and base gel groups during the experimental period. Acute inflammation and granular atrophy after UC induction were resolved completely completely by both 20% intracolonic gel and 3000 mg/kg orally. An increase in MPO activity and a decrease in MDA level in response to oral and intracolonic gel form of C. officinalis were observed 3 and and 7 days after treatment (P < 0.05. Conclusion: Our results indicate that oral and enema forms of hydroalcoholic extract of C. officinalis can be offered as are potential therapeutic agents for UC induced in rats.

  14. Acetic acid induces pH-independent cellular energy depletion in Salmonella enterica.

    Science.gov (United States)

    Tan, Sin Mei; Lee, Sui Mae; Dykes, Gary A

    2015-03-01

    Weak organic acids are widely used as preservatives and disinfectants in the food industry. Despite their widespread use, the antimicrobial mode of action of organic acids is still not fully understood. This study investigated the effect of acetic acid on the cell membranes and cellular energy generation of four Salmonella strains. Using a nucleic acid/protein assay, it was established that acetic acid did not cause leakage of intracellular components from the strains. A scanning electron microscopy study further confirmed that membrane disruption was not the antimicrobial mode of action of acetic acid. Some elongated Salmonella cells observed in the micrographs indicated a possibility that acetic acid may inhibit DNA synthesis in the bacterial cells. Using an ATP assay, it was found that at a neutral pH, acetic acid caused cellular energy depletion with an ADP/ATP ratio in the range between 0.48 and 2.63 (pacid molecules. The antimicrobial effect of acetic acid was better under acidic conditions (ADP/ATP ratio of 5.56 ± 1.27; pacid molecules can act together. We concluded that the inhibitory effect of acetic acid is not solely attributable to acidic pH but also to undissociated acid molecules. This finding has implication for the use of acetic acid as an antimicrobial against Salmonella on food products, such as chicken meat, which can buffer its pH.

  15. Increased intestinal protein permeability in a model of lung injury induced by phorbol myristate acetate.

    Science.gov (United States)

    St John, R C; Mizer, L A; Weisbrode, S E; Dorinsky, P M

    1991-11-01

    Multiple nonpulmonary organ failure is a frequent complication of the adult respiratory distress syndrome (ARDS), and contributes significantly to the high mortality rate associated with this disorder. Although previous studies suggest that systemic organ injury may be an integral component of ARDS, little is known about the specific functional alterations that occur in these target organs. The present study was designed, therefore, to test the hypothesis that endothelial damage, as assessed by microvascular permeability changes, develops in systemic organs in a model of acute lung injury. To test this postulate, the microvascular permeability for total protein was estimated using the steady-state relationship between the lymph (CL) to plasma (Cp) protein concentration ratio (i.e., CL/Cp) and lymph flow in autoperfused cat ileum preparations. Specifically, CL/Cp was measured in five cats, 2 h after acute lung injury was induced by intravenously administered phorbol myristate acetate (PMA), 15 micrograms/kg, and the results were compared with those of seven time-matched control animals. Prior to PMA infusion, the PaO2/FIO2 ratio was 451 +/- 28 in both groups and remained unchanged (486 +/- 26) in the control group. By contrast, the PaO2/FIO2 ratio fell to 275 +/- 95 after PMA infusion (p less than 0.05). In addition, whereas CL/Cp was 0.099 +/- 0.008 in the control animals, it increased to 0.36 +/- 0.06 in the PMA-injured animals (p less than 0.01). In summary, this study demonstrated that in this model of acute lung injury produced by PMA-induced activation of circulating inflammatory cells, both acute lung injury and systemic organ injury (i.e., morphologic and permeability alterations) occurred.

  16. Effect of glatiramer acetate on short-term memory impairment induced by lipopolysaccharide in male mice.

    Science.gov (United States)

    Mohammadi, Fatemeh; Rahimian, Reza; Fakhraei, Nahid; Rezayat, Seyed Mahdi; Javadi-Paydar, Mehrak; Dehpour, Ahmad R; Afshari, Khashayar; Ejtemaei Mehr, Shahram

    2016-08-01

    Glatiramer acetate (GA) demonstrates neuroprotective, neurogenesis, and anti-inflammatory properties. This study examines the probable protective effect of acute GA on lipopolysaccharide (LPS)-induced memory impairment in male mice and further explores which routes of administration [subcutaneous (s.c.) or intracerebroventricular (i.c.v.)] exert optimum effect. Memory performance was evaluated in two-trial recognition Y-maze and passive-avoidance tasks evaluating special recognition memory and fear memory, respectively. Memory impairment was induced by LPS [100 μg/kg, intraperitoneally (i.p.)], 4 h before training. In Y-maze, GA (10, 2.5, 0.625, 0.153, and 0.03 mg/kg, s.c.; 250 μg/mouse; i.c.v.) was administered 10 min following LPS, and special memory was assayed in Y-maze apparatus. In passive avoidance, LPS (100, 250 μg/kg; i.p.) was injected 4 h before receiving foot shock, and GA (10, 2.5; s.c.) or (250 μg/mouse; i.c.v.) was administered 4 h before the shock. Following 24 h, the fear memory was evaluated. Memory impaired significantly following LPS (100, 250 μg/kg; i.p.) in Y-maze and passive-avoidance tasks, P maze reversed memory impairment (LPS 100 μg/kg, i.p.) (P mice showed significantly longer latency times during the retention trial (P memory impairment both centrally and systemically. It improved spatial recognition memory increasing the average time in the novel arm and improved fear memory increasing latency time. GA administration improved memory impairment profoundly through both systemic and central routs.

  17. Agonist-induced activation of histamine H3 receptor signals to extracellular signal-regulated kinases 1 and 2 through PKC-, PLD-, and EGFR-dependent mechanisms.

    Science.gov (United States)

    Lai, Xiangru; Ye, Lingyan; Liao, Yuan; Jin, Lili; Ma, Qiang; Lu, Bing; Sun, Yi; Shi, Ying; Zhou, Naiming

    2016-04-01

    The histamine H3 receptor (H3R), abundantly expressed in the central and the peripheral nervous system, has been recognized as a promising target for the treatment of various important CNS diseases including narcolepsy, Alzheimer's disease, and attention deficit hyperactivity disorder. The H3R acts via Gi/o -proteins to inhibit adenylate cyclase activity and modulate MAPK activity. However, the underlying molecular mechanisms for H3R mediation of the activation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) remain to be elucidated. In this study, using HEK293 cells stably expressing human H3R and mouse primary cortical neurons endogenously expressing mouse H3R, we found that the H3R-mediated activation of ERK1/2 was significantly blocked by both the pertussis toxin and the MEK1/2 inhibitor U0126. Upon stimulation by H3R agonist histamine or imetit, H3R was shown to rapidly induce ERK1/2 phosphorylation via PLC/PKC-, PLDs-, and epidermal growth factor receptor (EGFR) transactivation-dependent pathways. Furthermore, it was also indicated that while the βγ-subunits play a key role in H3R-activated ERK1/2 phosphorylation, β-arrestins were not required for ERK1/2 activation. In addition, when the cultured mouse cortical neurons were exposed to oxygen and glucose deprivation conditions (OGD), imetit exhibited neuroprotective properties through the H3R. Treatment of cells with the inhibitor UO126 abolished these protective effects. This suggests a possible neuroprotective role of the H3R-mediated ERK1/2 pathway under hypoxia conditions. These observations may provide new insights into the pharmacological effects and the physiological functions modulated by the H3R-mediated activation of ERK1/2. Histamine H3 receptors are abundantly expressed in the brain and play important roles in various CNS physiological functions. However, the underlying mechanisms for H3R-induced activation of extracellular signal-regulated kinase (ERK)1/2 remain largely unknown. Here

  18. Ibrutinib selectively and irreversibly targets EGFR (L858R, Del19) mutant but is moderately resistant to EGFR (T790M) mutant NSCLC Cells

    OpenAIRE

    Wu, Hong; Wang, Aoli; Zhang, Wei; Wang, Beilei; Chen, Cheng; Wang, Wenchao; Hu, Chen; Ye, Zi; Zhao, Zheng; Wang, Li; Li, Xixiang; Yu, Kailin; Liu, Juan; Wu, Jiaxin; Yan, Xiao-E

    2015-01-01

    Through comprehensive comparison study, we found that ibrutinib, a clinically approved covalent BTK kinase inhibitor, was highly active against EGFR (L858R, del19) mutant driven NSCLC cells, but moderately active to the T790M ‘gatekeeper’ mutant cells and not active to wild-type EGFR NSCLC cells. Ibrutinib strongly affected EGFR mediated signaling pathways and induced apoptosis and cell cycle arrest (G0/G1) in mutant EGFR but not wt EGFR cells. However, ibrutinib only slowed down tumor progre...

  19. Protective effect of ethyl acetate fraction of Rhododendron arboreum flowers against carbon tetrachloride-induced hepatotoxicity in experimental models

    Directory of Open Access Journals (Sweden)

    Neeraj Verma

    2011-01-01

    Result and Discussion: The substantially elevated serum enzymatic activities of SGOT, SGPT, SALP, γ-GT, and bilirubin due to CCl 4 treatment were restored toward normal in a dose-dependent manner. Meanwhile, the decreased activities of GST and glutathione reductase were also restored toward normal. In addition, ethyl acetate fraction also significantly prevented the elevation of hepatic malondialdehyde formation and depletion of reduced glutathione content in the liver of CCl 4 -intoxicated rats in a dose-dependent manner. Silymarin used as standard reference also exhibited significant hepatoprotective activity on post-treatment against CCl 4 -induced hepatotoxicity in rats. The biochemical observations were supplemented with histopathological examination of rat liver sections. The results of this study strongly indicate that ethyl acetate fraction has a potent hepatoprotective action against CCl 4 -induced hepatic damage in rats.

  20. Protective effect of the methanolic extract of malva parviflora l. leaves on acetic acid-induced ulcerative colitis in rats

    Directory of Open Access Journals (Sweden)

    Aisha Dugani

    2016-01-01

    Full Text Available Background/Aims: Inflammatory bowel disease (IBD is a general term describing chronic, idiopathic relapsing, inflammatory conditions of the gastrointestinal tract of unknown etiology. Previous studies have indicated that Malva parviflora leaf extract possesses anti-inflammatory, antioxidant, and antiulcerogenic activity. activity. This work aimed to investigatee the anti-inflammatory effect of the methanolic (MEMP and aqueous (AEMP extracts of M. parviflora leaves on acetic acid-induced colitis in rats. Materials and Methods: 42 male Wistar albino rats were divided into seven groups (n = 6. Group I: Normal saline control group with no colitis; Group II: Acetic acid colitis group; Group III: 100 mg/kg/5 d MEMP; Group IV: 200 mg/kg/5 d.MEMP; Group V: 100 mg/kg/5 d AEMP; Group VI: 200 mg/kg/5 d AEMP; Group VII: Prednisolone group (2 mg/kg/5 d. Treatments were followed by induction of colitis using intrarectal instillation of 2 mL of 4% acetic acid. Colon damage was evaluated macroscopically (spleen weight/body weight, colon weight/length ratio and the histological changes were also recorded. Results: The results of this study showed that acetic acid caused severe inflammation of the colon and a significant increase in spleen weight/body weight, and an increase in colon weight/length ratio compared with normal control group. Pretreatment with MEMP and AEMP for 5 days followed by induction of colitis resulted in a significant attenuation of spleen weight and colon weight/length ratio compared with acetic acid control group. Methanolic extract provided better anticolitic effect than aqueous extract; the effect was prominent at the dose of 200 mg/kg. Histopathological findings confirmed the protective effect of the MEMP. Conclusion: In conclusion, MEMP could ameliorate mucosal damage in experimentally induced colitis when given orally.

  1. Anti-inflammatory effect of Moringa oleifera Lam. seeds on acetic acid-induced acute colitis in rats

    OpenAIRE

    Mohsen Minaiyan; Gholamreza Asghari; Diana Taheri; Mozhgan Saeidi; Salar Nasr-Esfahani

    2014-01-01

    Objective: Anti-inflammatory, immuno-modulatory, and antioxidant properties of Moringa oleifera Lam. suggest that it might have beneficial effects on colitis. The present study was performed to investigate the anticolitis effect of Moringa oleifera seeds hydro-alcoholic extract (MSHE) and its chloroform fraction (MCF) on acetic acid-induced colitis in rats. Materials and Methods: Both MSHE and MCF with three increasing doses (50, 100, and 200 mg/kg) were administered orally to separate groups...

  2. 12-O-tetradecanoylphorbol 13-acetate-inducible proteins are synthesized at an increased rate in Bloom syndrome fibroblasts.

    OpenAIRE

    Mallick, U; Rahmsdorf, H J; N Yamamoto; Ponta, H; Wegner, R D; Herrlich, P

    1982-01-01

    A set of proteins, which in normal fibroblasts were barely, if at all, detectable, were synthesized at an increased rate in fibroblasts from patients with Bloom syndrome (BS). The same set of proteins was induced in normal human fibroblasts by treatment with 12-O-tetradecanoylphorbol 13-acetate (TPA). In BS cells, TPA caused a further 2-fold increase in the rate of synthesis. Production of these proteins was inhibited by the addition of fluocinolone acetonide to the culture medium. One of the...

  3. Comparative Study of Berberis vulgaris Fruit Extract and Berberine Chloride Effects on Acetic Acid-Induced Colitis in Rats

    OpenAIRE

    Minaiyan, Mohsen; Ghannadi, Alireza; Mahzouni, Parvin; Jaffari-Shirazi, Elham

    2011-01-01

    Antioxidant and immunomodulatory effects of anthocyanins are abundant in berberry fruits suggesting that they may have beneficial effects on inflammatory bowel diseases (IBD). The present study was carried out to investigate the anti-colitic effect of Berberis vulgaris fruit extract (BFE) compared to berberine chloride (BEC) and corticosteroids using an animal model of acetic acid induced experimental colitis. BFE with three different doses (375, 750, and 1500 mg/Kg) was administered orally o...

  4. MITF Modulates Therapeutic Resistance through EGFR Signaling.

    Science.gov (United States)

    Ji, Zhenyu; Erin Chen, Yiyin; Kumar, Raj; Taylor, Michael; Jenny Njauw, Ching-Ni; Miao, Benchun; Frederick, Dennie T; Wargo, Jennifer A; Flaherty, Keith T; Jönsson, Göran; Tsao, Hensin

    2015-07-01

    Response to targeted therapies varies significantly despite shared oncogenic mutations. Nowhere is this more apparent than in BRAF (V600E)-mutated melanomas where initial drug response can be striking and yet relapse is commonplace. Resistance to BRAF inhibitors have been attributed to the activation of various receptor tyrosine kinases (RTKs), although the underlying mechanisms have been largely uncharacterized. Here, we found that EGFR-induced vemurafenib resistance is ligand dependent. We employed whole-genome expression analysis and discovered that vemurafenib resistance correlated with the loss of microphthalmia-associated transcription factor (MITF), along with its melanocyte lineage program, and with the activation of EGFR signaling. An inverse relationship between MITF, vemurafenib resistance, and EGFR was then observed in patient samples of recurrent melanoma and was conserved across melanoma cell lines and patients' tumor specimens. Functional studies revealed that MITF depletion activated EGFR signaling and consequently recapitulated the resistance phenotype. In contrast, forced expression of MITF in melanoma and colon cancer cells inhibited EGFR and conferred sensitivity to BRAF/MEK inhibitors. These findings indicate that an "autocrine drug resistance loop" is suppressed by melanocyte lineage signal(s), such as MITF. This resistance loop modulates drug response and could explain the unique sensitivity of melanomas to BRAF inhibition. PMID:25789707

  5. Tumor hypoxia, the Warburg effect, and multidrug resistance: Modulation of hypoxia induced MDR using EGFR-targeted polymer blend nanocarriers for combination paclitaxel/lonidamine therapy

    Science.gov (United States)

    Jabr-Milane, Lara Scheherazade

    Multi-drug resistant (MDR) cancer is a significant clinical obstacle and is often implicated in cases of recurrent, non-responsive disease. The biological focus of this work is to explore the relationship between the hypoxic microenvironment of a tumor, the development of MDR, and the energetic profile characteristic of the Warburg effect (aerobic glycolysis). The therapeutic aim of this research is to develop an EGFR-targeted nanocarrier system for combination (paclitaxel/lonidamine) therapy for the treatment of MDR cancer. The stability of the nanocarrier formulation was validated in vitro and the system was characterized for drug release kinetics, size, surface modification, and EGFR-targeting ability. An orthotopic animal model of hypoxic, MDR breast cancer was developed for the pre-clinical evaluation of this system. The EGFR-targeted nanoparticles loaded with lonidamine and paclitaxel demonstrated superior pharmacokinetic parameters relative to non-targeted nanoparticles and drug solution. Combination therapy with lonidamine and paclitaxel, in solution and EGFR-targeted nanoparticle form, was more effective at suppressing tumor growth than single agent treatment. However, combination therapy with EGFR-targeted nanoparticles was less toxic than treatment with drug solution. Combination therapy did change the MDR and hypoxic character of the tumors as demonstrated by a decrease in marker proteins. This EGFR-targeted combination nanocarrier therapy has the potential to make the successful treatment of MDR a clinical reality.

  6. Multiple myeloma acquires resistance to EGFR inhibitor via induction of pentose phosphate pathway.

    Science.gov (United States)

    Chen, Yan; Huang, Ruibin; Ding, Jianghua; Ji, Dexiang; Song, Bing; Yuan, Liya; Chang, Hong; Chen, Guoan

    2015-04-20

    Multiple myeloma (MM) was characterized by frequent mutations in KRAS/NRAS/BRAF within the EGFR pathway that could induce resistance to EGFR inhibitors. We here report that EGFR inhibition solely exhibited moderate inhibition in KRAS/NRAS/BRAF wildtype (triple-WT) MM cells, whilst had no effect in myeloma cells with any of the mutated genes. The moderate inhibitory effect was conferred by induction of pentose phosphate pathway (PPP) when cells were treated with Gefitinib, the EGFR inhibitor. Combination of Gefitinib with PPP inhibitor 6AN effected synergistically in triple-WT cells. The inhibition could be restored by addition of NADPH. Dual EGFR/ERBB2 inhibitor Afatinib also exhibited similar effects. Further genetic silencing of EGFR, ERBB2 and mTOR indicated that major effect conferred by ERBB2 was via convergence to EGFR pathway in MM. Our results contributed to the individualized targeted therapy with EGFR inhibitors in MM.

  7. (-)-Bornyl acetate induces autonomic relaxation and reduces arousal level after visual display terminal work without any influences of task performance in low-dose condition.

    Science.gov (United States)

    Matsubara, Eri; Fukagawa, Mio; Okamoto, Tsuyoshi; Ohnuki, Koichiro; Shimizu, Kuniyoshi; Kondo, Ryuichiro

    2011-04-01

    (-)-Bornyl acetate is the main volatile constituent in numerous conifer oils and has a camphoraceous, pine-needle-like odor. It is frequently used as the conifer needle composition in soap, bath products, room sprays, and pharmaceutical products. However, the psychophysiological effects of (-)-bornyl acetate remained unclear. We investigated the effects of breathing air mixed with (-)-bornyl acetate at different doses (low-dose and high-dose conditions) on the individuals during and after VDT (visual display terminal) work using a visual discrimination task. The amounts of (-)-bornyl acetate through our odorant delivery system for 40 min were 279.4 µg in the low-dose and 716.3 µg in the high-dose (-)-bornyl acetate condition. (-)-Bornyl acetate induced changes of autonomic nervous system for relaxation and reduced arousal level after VDT work without any influences of task performance in low-dose condition, but not in high-dose condition.

  8. Survivin upregulation, dependent on leptin-EGFR-Notch1 axis, is essential for leptin induced migration of breast carcinoma cells

    OpenAIRE

    Knight, Brandi B.; Oprea-Ilies, Gabriela M.; Nagalingam, Arumugam; Yang, Lily; Cohen, Cynthia; Saxena, Neeraj K; Sharma, Dipali

    2011-01-01

    Obese breast cancer patients exhibit a higher risk for larger tumor burden and increased metastasis. Molecular effects of obesity on carcinogenesis are mediated by autocrine and paracrine effects of adipocytokine leptin. Leptin participates in tumor progression and metastasis of human breast. We show that leptin induces clonogenicity and migration potential of breast cancer cells. We found that survivin expression is induced in response to leptin. In this study, we examine the role and leptin...

  9. Memory CD8(+) T Cells Require Increased Concentrations of Acetate Induced by Stress for Optimal Function.

    Science.gov (United States)

    Balmer, Maria L; Ma, Eric H; Bantug, Glenn R; Grählert, Jasmin; Pfister, Simona; Glatter, Timo; Jauch, Annaïse; Dimeloe, Sarah; Slack, Emma; Dehio, Philippe; Krzyzaniak, Magdalena A; King, Carolyn G; Burgener, Anne-Valérie; Fischer, Marco; Develioglu, Leyla; Belle, Réka; Recher, Mike; Bonilla, Weldy V; Macpherson, Andrew J; Hapfelmeier, Siegfried; Jones, Russell G; Hess, Christoph

    2016-06-21

    How systemic metabolic alterations during acute infections impact immune cell function remains poorly understood. We found that acetate accumulates in the serum within hours of systemic bacterial infections and that these increased acetate concentrations are required for optimal memory CD8(+) T cell function in vitro and in vivo. Mechanistically, upon uptake by memory CD8(+) T cells, stress levels of acetate expanded the cellular acetyl-coenzyme A pool via ATP citrate lyase and promoted acetylation of the enzyme GAPDH. This context-dependent post-translational modification enhanced GAPDH activity, catalyzing glycolysis and thus boosting rapid memory CD8(+) T cell responses. Accordingly, in a murine Listeria monocytogenes model, transfer of acetate-augmented memory CD8(+) T cells exerted superior immune control compared to control cells. Our results demonstrate that increased systemic acetate concentrations are functionally integrated by CD8(+) T cells and translate into increased glycolytic and functional capacity. The immune system thus directly relates systemic metabolism with immune alertness. PMID:27212436

  10. Genome-Wide Transcriptional Analysis Reveals the Protection against Hypoxia-Induced Oxidative Injury in the Intestine of Tibetans via the Inhibition of GRB2/EGFR/PTPN11 Pathways

    Science.gov (United States)

    Gesang, Luobu; Dan, Zeng; Gusang, Lamu

    2016-01-01

    The molecular mechanisms for hypoxic environment causing the injury of intestinal mucosal barrier (IMB) are widely unknown. To address the issue, Han Chinese from 100 m altitude and Tibetans from high altitude (more than 3650 m) were recruited. Histological and transcriptome analyses were performed. The results showed intestinal villi were reduced and appeared irregular, and glandular epithelium was destroyed in the IMB of Tibetans when compared with Han Chinese. Transcriptome analysis revealed 2573 genes with altered expression. The levels of 1137 genes increased and 1436 genes decreased in Tibetans when compared with Han Chinese. Gene ontology (GO) analysis indicated most immunological responses were reduced in the IMB of Tibetans when compared with Han Chinese. Gene microarray showed that there were 25-, 22-, and 18-fold downregulation for growth factor receptor-bound protein 2 (GRB2), epidermal growth factor receptor (EGFR), and tyrosine-protein phosphatase nonreceptor type 11 (PTPN11) in the IMB of Tibetans when compared with Han Chinese. The downregulation of EGFR, GRB2, and PTPN11 will reduce the production of reactive oxygen species and protect against oxidative stress-induced injury for intestine. Thus, the transcriptome analysis showed the protecting functions of IMB patients against hypoxia-induced oxidative injury in the intestine of Tibetans via affecting GRB2/EGFR/PTPN11 pathways.

  11. Stability of the acetic acid-induced bladder irritation model in alpha chloralose-anesthetized female cats.

    Directory of Open Access Journals (Sweden)

    F Aura Kullmann

    Full Text Available Time- and vehicle-related variability of bladder and urethral rhabdosphincter (URS activity as well as cardiorespiratory and blood chemistry values were examined in the acetic acid-induced bladder irritation model in α-chloralose-anesthetized female cats. Additionally, bladder and urethra were evaluated histologically using Mason trichrome and toluidine blue staining. Urodynamic, cardiovascular and respiratory parameters were collected during intravesical saline infusion followed by acetic acid (0.5% to irritate the bladder. One hour after starting acetic acid infusion, a protocol consisting of a cystometrogram, continuous infusion-induced rhythmic voiding contractions, and a 5 min "quiet period" (bladder emptied without infusion was precisely repeated every 30 minutes. Administration of vehicle (saline i.v. occurred 15 minutes after starting each of the first 7 cystometrograms and duloxetine (1mg/kg i.v. after the 8(th. Acetic acid infusion into the bladder increased URS-EMG activity, bladder contraction frequency, and decreased contraction amplitude and capacity, compared to saline. Bladder activity and URS activity stabilized within 1 and 2 hours, respectively. Duloxetine administration significantly decreased bladder contraction frequency and increased URS-EMG activity to levels similar to previous reports. Cardiorespiratory parameters and blood gas levels remained consistent throughout the experiment. The epithelium of the bladder and urethra were greatly damaged and edema and infiltration of neutrophils in the lamina propria of urethra were observed. These data provide an ample evaluation of the health of the animals, stability of voiding function and appropriateness of the model for testing drugs designed to evaluate lower urinary tract as well as cardiovascular and respiratory systems function.

  12. Stability of the acetic acid-induced bladder irritation model in alpha chloralose-anesthetized female cats.

    Science.gov (United States)

    Kullmann, F Aura; Wells, Grace I; Langdale, Christopher L; Zheng, Jihong; Thor, Karl B

    2013-01-01

    Time- and vehicle-related variability of bladder and urethral rhabdosphincter (URS) activity as well as cardiorespiratory and blood chemistry values were examined in the acetic acid-induced bladder irritation model in α-chloralose-anesthetized female cats. Additionally, bladder and urethra were evaluated histologically using Mason trichrome and toluidine blue staining. Urodynamic, cardiovascular and respiratory parameters were collected during intravesical saline infusion followed by acetic acid (0.5%) to irritate the bladder. One hour after starting acetic acid infusion, a protocol consisting of a cystometrogram, continuous infusion-induced rhythmic voiding contractions, and a 5 min "quiet period" (bladder emptied without infusion) was precisely repeated every 30 minutes. Administration of vehicle (saline i.v.) occurred 15 minutes after starting each of the first 7 cystometrograms and duloxetine (1mg/kg i.v.) after the 8(th). Acetic acid infusion into the bladder increased URS-EMG activity, bladder contraction frequency, and decreased contraction amplitude and capacity, compared to saline. Bladder activity and URS activity stabilized within 1 and 2 hours, respectively. Duloxetine administration significantly decreased bladder contraction frequency and increased URS-EMG activity to levels similar to previous reports. Cardiorespiratory parameters and blood gas levels remained consistent throughout the experiment. The epithelium of the bladder and urethra were greatly damaged and edema and infiltration of neutrophils in the lamina propria of urethra were observed. These data provide an ample evaluation of the health of the animals, stability of voiding function and appropriateness of the model for testing drugs designed to evaluate lower urinary tract as well as cardiovascular and respiratory systems function. PMID:24040064

  13. p85α promotes nucleolin transcription and subsequently enhances EGFR mRNA stability and EGF-induced malignant cellular transformation.

    Science.gov (United States)

    Xie, Qipeng; Guo, Xirui; Gu, Jiayan; Zhang, Liping; Jin, Honglei; Huang, Haishan; Li, Jingxia; Huang, Chuanshu

    2016-03-29

    p85α is a regulatory subunit of phosphatidylinositol 3-kinase (PI3K) that is a key lipid enzyme for generating phosphatidylinositol 3, 4, 5-trisphosphate, and subsequently activates signaling that ultimately regulates cell cycle progression, cell growth, cytoskeletal changes, and cell migration. In addition to form a complex with the p110 catalytic subunit, p85α also exists as a monomeric form due to that there is a greater abundance of p85α than p110 in many cell types. Our previous studies have demonstrated that monomeric p85α exerts a pro-apoptotic role in UV response through induction of TNF-α gene expression in PI3K-independent manner. In current studies, we identified a novel biological function of p85α as a positive regulator of epidermal growth factor receptor (EGFR) expression and cell malignant transformation via nucleolin-dependent mechanism. Our results showed that p85α was crucial for EGFR and nucleolin expression and subsequently resulted in an increase of malignant cellular transformation by using both specific knockdown and deletion of p85α in its normal expressed cells. Mechanistic studies revealed that p85α upregulated EGFR protein expression mainly through stabilizing its mRNA, whereas nucleolin (NCL) was able to bind to egfr mRNA and increase its mRNA stability. Consistently, overexpression of NCL in p85α-/- cells restored EGFR mRNA stabilization, protein expression and cell malignant transformation. Moreover, we discovered that p85α upregulated NCL gene transcription via enhancing C-Jun activation. Collectively, our studies demonstrate a novel function of p85α as a positive regulator of EGFR mRNA stability and cell malignant transformation, providing a significant insight into the understanding of biomedical nature of p85α protein in mammalian cells and further supporting that p85α might be a potential target for cancer prevention and therapy. PMID:26918608

  14. p85α promotes nucleolin transcription and subsequently enhances EGFR mRNA stability and EGF-induced malignant cellular transformation

    Science.gov (United States)

    Gu, Jiayan; Zhang, Liping; Jin, Honglei; Huang, Haishan; Li, Jingxia; Huang, Chuanshu

    2016-01-01

    p85α is a regulatory subunit of phosphatidylinositol 3-kinase (PI3K) that is a key lipid enzyme for generating phosphatidylinositol 3, 4, 5-trisphosphate, and subsequently activates signaling that ultimately regulates cell cycle progression, cell growth, cytoskeletal changes, and cell migration. In addition to form a complex with the p110 catalytic subunit, p85α also exists as a monomeric form due to that there is a greater abundance of p85α than p110 in many cell types. Our previous studies have demonstrated that monomeric p85α exerts a pro-apoptotic role in UV response through induction of TNF-α gene expression in PI3K-independent manner. In current studies, we identified a novel biological function of p85α as a positive regulator of epidermal growth factor receptor (EGFR) expression and cell malignant transformation via nucleolin-dependent mechanism. Our results showed that p85α was crucial for EGFR and nucleolin expression and subsequently resulted in an increase of malignant cellular transformation by using both specific knockdown and deletion of p85α in its normal expressed cells. Mechanistic studies revealed that p85α upregulated EGFR protein expression mainly through stabilizing its mRNA, whereas nucleolin (NCL) was able to bind to egfr mRNA and increase its mRNA stability. Consistently, overexpression of NCL in p85α−/− cells restored EGFR mRNA stabilization, protein expression and cell malignant transformation. Moreover, we discovered that p85α upregulated NCL gene transcription via enhancing C-Jun activation. Collectively, our studies demonstrate a novel function of p85α as a positive regulator of EGFR mRNA stability and cell malignant transformation, providing a significant insight into the understanding of biomedical nature of p85α protein in mammalian cells and further supporting that p85α might be a potential target for cancer prevention and therapy. PMID:26918608

  15. Does Sunscreen Prevent Epidermal Growth Factor Receptor (EGFR) Inhibitor–Induced Rash? Results of a Placebo-Controlled Trial from the North Central Cancer Treatment Group (N05C4)

    Science.gov (United States)

    Thrower, Abby; Sloan, Jeff A.; Flynn, Patrick J.; Wentworth-Hartung, Nicole Lea; Dakhil, Shaker R.; Mattar, Bassam I.; Nikcevich, Daniel A.; Novotny, Paul; Sekulic, Aleksandar; Loprinzi, Charles L.

    2010-01-01

    Purpose. Rash occurs in >50% of patients prescribed epidermal growth factor receptor (EGFR) inhibitors. This study was undertaken to determine whether sunscreen prevents or mitigates these rashes. Methods. This placebo-controlled, double-blinded trial enrolled rash-free patients starting an EGFR inhibitor. Patients were randomly assigned to sunscreen with a sun protection factor of 60 applied twice a day for 28 days versus placebo. They were then monitored for rash and quality of life (Skindex-16) during the 4-week intervention and for an additional 4 weeks. Results. Fifty-four patients received sunscreen, and 56 received placebo; the arms were balanced at baseline. During the 4-week intervention, physician-reported rash occurred in 38 (78%) and 39 (80%) sunscreen-treated and placebo-exposed patients, respectively (p = 1.00); no significant differences in rash rates emerged over the additional 4 weeks. There were no significant differences in rash severity, and patient-reported outcomes of rash yielded similar conclusions. Adjustment for sun intensity by geographical zone, season, and use of photosensitivity medications did not yield a significant difference in rash across study arms (p = .20). Quality of life scores declined but remained comparable between arms. Conclusions. Sunscreen, as prescribed in this trial, did not prevent or attenuate EGFR inhibitor–induced rash. PMID:20798191

  16. Intratumor heterogeneity and chemotherapy-induced changes in EGFR status in non-small cell lung cancer

    DEFF Research Database (Denmark)

    Jakobsen, Jan Nyrop; Sørensen, Jens Benn

    2012-01-01

    Biomarker expression is increasingly being used to customize treatment in non-small cell lung cancer (NSCLC). The choice of systemic treatment usually depends on biomarker expression in the initial diagnostic biopsy taken before initiation of first-line treatment. Chemotherapy induces DNA damages...... in the tumor cells, and thus, biomarker expression in the tumor after systemic treatment might not be identical to biomarker expression in the diagnostic biopsy. NSCLC is highly heterogeneous and biomarker expression may vary in different areas within the same tumor. This review explores the tumor...

  17. Remarkable increase in 14C-acetate uptake in an epilepsy model rat brain induced by lithium-pilocarpine.

    Science.gov (United States)

    Hosoi, Rie; Kitano, Daisuke; Momosaki, Sotaro; Kuse, Kenji; Gee, Antony; Inoue, Osamu

    2010-01-22

    The present study demonstrates changes in rat brain glial metabolism during the acute phase of epilepsy. Status epilepticus (SE) was induced using the lithium-pilocarpine model. Glial metabolism was measured with (14)C-acetate. Local cerebral blood flow and glucose metabolism were also measured using (14)C-N-isopropyl-p-iodoamphetamine (IMP) and (14)C-2-deoxyglucose (2DG), respectively. At the initiation of the seizure, (14)C-acetate uptake did not change significantly. However, a marked increase was observed 2 h after the pilocarpine injection in all brain regions studied. The increase of brain uptake was transient, and the maximum enhancement was seen at 2 h after the pilocarpine injection. The increase of (14)C-acetate uptake was almost to the same degree in all regions, whereas (14)C-IMP and (14)C-2DG uptakes showed a heterogeneous increase. In the case of (14)C-IMP, the highest increase was observed in the thalamus (280%), and a moderate increase (120 to 150%) was seen in the orbital cortex, cingulate cortex and pyriform cortex. (14)C-2DG uptake increased by 130 to 240% in most regions of the brain, however, an increase of only 40 and 20% was observed in the cerebellum and pons-medulla, respectively. These results demonstrated that glial energy metabolism was markedly enhanced during a prolonged seizure. To our knowledge, this study is the first observation showing large and widespread glial metabolic increases in the rat brain during status epilepticus.

  18. Novel irreversible EGFR tyrosine kinase inhibitor 324674 sensitizes human colon carcinoma HT29 and SW480 cells to apoptosis by blocking the EGFR pathway

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Zhiwei; Cui, Binbin; Jin, Yinghu; Chen, Haipeng [Division of Colorectal Surgery, Third Affiliated Hospital of Harbin Medical University, Harbin (China); Wang, Xishan, E-mail: wxshan_oncologist@yahoo.com.cn [Division of Colorectal Surgery, Third Affiliated Hospital of Harbin Medical University, Harbin (China)

    2011-08-12

    Highlights: {yields} This article described the effects of the EGFR tyrosine kinase inhibitor on the cell proliferation and the apoptosis induction of the colon carcinoma cell lines. {yields} Demonstrated that 326474 is a more potent EGFR inhibitor on colon cancer cells than other three TKIs. {yields} It can be important when considering chemotherapy for colonic cancer patients. -- Abstract: Background: Epidermal growth factor receptor (EGFR) is widely expressed in multiple solid tumors including colorectal cancer by promoting cancer cell growth and proliferation. Therefore, the inhibition of EGFR activity may establish a clinical strategy of cancer therapy. Methods: In this study, using human colon adenocarcinoma HT29 and SW480 cells as research models, we compared the efficacy of four EGFR inhibitors in of EGFR-mediated pathways, including the novel irreversible inhibitor 324674, conventional reversible inhibitor AG1478, dual EGFR/HER2 inhibitor GW583340 and the pan-EGFR/ErbB2/ErbB4 inhibitor. Cell proliferation was assessed by MTT analysis, and apoptosis was evaluated by the Annexin-V binding assay. EGFR and its downstream signaling effectors were examined by western blotting analysis. Results: Among the four inhibitors, the irreversible EGFR inhibitor 324674 was more potent at inhibiting HT29 and SW480 cell proliferation and was able to efficiently induce apoptosis at lower concentrations. Western blotting analysis revealed that AG1478, GW583340 and pan-EGFR/ErbB2/ErbB4 inhibitors failed to suppress EGFR activation as well as the downstream mitogen-activated protein kinase (MAPK) and PI3K/AKT/mTOR (AKT) pathways. In contrast, 324674 inhibited EGFR activation and the downstream AKT signaling pathway in a dose-dependent manner. Conclusion: Our studies indicated that the novel irreversible EGFR inhibitor 324674 may have a therapeutic application in colon cancer therapy.

  19. Mutant KRas-Induced Mitochondrial Oxidative Stress in Acinar Cells Upregulates EGFR Signaling to Drive Formation of Pancreatic Precancerous Lesions

    Directory of Open Access Journals (Sweden)

    Geou-Yarh Liou

    2016-03-01

    Full Text Available The development of pancreatic cancer requires the acquisition of oncogenic KRas mutations and upregulation of growth factor signaling, but the relationship between these is not well established. Here, we show that mutant KRas alters mitochondrial metabolism in pancreatic acinar cells, resulting in increased generation of mitochondrial reactive oxygen species (mROS. Mitochondrial ROS then drives the dedifferentiation of acinar cells to a duct-like progenitor phenotype and progression to PanIN. This is mediated via the ROS-receptive kinase protein kinase D1 and the transcription factors NF-κB1 and NF-κB2, which upregulate expression of the epidermal growth factor, its ligands, and their sheddase ADAM17. In vivo, interception of KRas-mediated generation of mROS reduced the formation of pre-neoplastic lesions. Hence, our data provide insight into how oncogenic KRas interacts with growth factor signaling to induce the formation of pancreatic cancer.

  20. Synergism between Hedgehog-GLI and EGFR signaling in Hedgehog-responsive human medulloblastoma cells induces downregulation of canonical Hedgehog-target genes and stabilized expression of GLI1.

    Directory of Open Access Journals (Sweden)

    Frank Götschel

    Full Text Available Aberrant activation of Hedgehog (HH signaling has been identified as a key etiologic factor in many human malignancies. Signal strength, target gene specificity, and oncogenic activity of HH signaling depend profoundly on interactions with other pathways, such as epidermal growth factor receptor-mediated signaling, which has been shown to cooperate with HH/GLI in basal cell carcinoma and pancreatic cancer. Our experimental data demonstrated that the Daoy human medulloblastoma cell line possesses a fully inducible endogenous HH pathway. Treatment of Daoy cells with Sonic HH or Smoothened agonist induced expression of GLI1 protein and simultaneously prevented the processing of GLI3 to its repressor form. To study interactions between HH- and EGF-induced signaling in greater detail, time-resolved measurements were carried out and analyzed at the transcriptomic and proteomic levels. The Daoy cells responded to the HH/EGF co-treatment by downregulating GLI1, PTCH, and HHIP at the transcript level; this was also observed when Amphiregulin (AREG was used instead of EGF. We identified a novel crosstalk mechanism whereby EGFR signaling silences proteins acting as negative regulators of HH signaling, as AKT- and ERK-signaling independent process. EGFR/HH signaling maintained high GLI1 protein levels which contrasted the GLI1 downregulation on the transcript level. Conversely, a high-level synergism was also observed, due to a strong and significant upregulation of numerous canonical EGF-targets with putative tumor-promoting properties such as MMP7, VEGFA, and IL-8. In conclusion, synergistic effects between EGFR and HH signaling can selectively induce a switch from a canonical HH/GLI profile to a modulated specific target gene profile. This suggests that there are more wide-spread, yet context-dependent interactions, between HH/GLI and growth factor receptor signaling in human malignancies.

  1. Protective Effect of Cod (Gadus macrocephalus) Skin Collagen Peptides on Acetic Acid-Induced Gastric Ulcer in Rats.

    Science.gov (United States)

    Niu, Huina; Wang, Zhicong; Hou, Hu; Zhang, Zhaohui; Li, Bafang

    2016-07-01

    This research was performed to explore the protective effect of cod skin collagen peptides (CCP) on gastric ulcer induced by acetic acid. The CCP were fractionated into low molecular CCP (LMCCP, Mw 3 kDa). In HMCCP and LMCCP, glycine of accounted for about one-third of the total amino acids without cysteine and tryptophan, and hydrophobic amino acids accounted for about 50%. After 21 d CCP treatment (60 or 300 mg/kg, p.o./daily), the healing effects on acetic acid-induced gastric ulcers were evaluated by macroscopic measure, microscopic measure, and immune histochemistry. Moreover, the expression levels of the growth factors, such as vascular endothelial growth factor, epidermal growth factor, transforming growth factor β1 (TGFβ1), and the heat shock protein 70 (HSP70) was detected. The results showed that both LMCCP and HMCCP could significantly decrease the ulcer areas and promote the healing of the lesions. They also could improve the levels of hexosamine, glutathione, superoxide dismutase, and glutathione peroxidase, and reduce the content of malondialdehyde and inducible nitric oxide synthase. In addition, the expression level of TGFβ1 gene and HSP70 mRNA was significantly improved by the treatment. It suggested that CCP could be able to improve symptoms of gastric ulcer and probably be used in the treatment of gastric ulcer. PMID:27219644

  2. Testosterone undecanoate and depo medroxyprogesterone acetate induced azoospermia through increased expression of spermatogenic cell caspase 3

    OpenAIRE

    Nukman Moeloek; Asmarinah Asmarinah; Nurjati C. Siregar; Syafruddin Ilyas

    2008-01-01

    The administration of a combination of testosterone undecanoate (TU, a long-acting androgen) and depo-medroxyprogesterone acetate (DMPA) were investigated in term of suppression of rat sperm concentration in vivo to azoospermia through increasing activity of spermatogenic cell caspase 3. Adult Sprague Dawley rats received TU and DMPA of 2.5 mg and 1.25 mg, respectively, a regimen known to rapidly reduce intra testicular testosterone and to produce azoospermia within 12 weeks. Caspase 3 positi...

  3. Treatment of mouse melanoma cells with phorbol 12-myristate 13-acetate counteracts mannosylerythritol lipid-induced growth arrest and apoptosis

    OpenAIRE

    Zhao, Xiaoxian; Geltinger, Christian; Kishikawa, Shotaro; Ohshima, Kiyoshi; Murata, Takehide; Nomura, Nobuhiko; Nakahara, Tadaatsu; Yokoyama, Kazunari K.

    2000-01-01

    Mannosylerythritol lipid (MEL), an extracellularglycolipid from yeast, induces the differentiation ofHL-60 promyelocytic leukemia cells towardsgranulocytes. We show here that MEL is also a potentinhibitor of the proliferation of mouse melanoma B16cells. Flow-cytometric analysis of the cell cycle ofMEL-treated B16 cells revealed the accumulation ofcells in the sub-G0/G1 phase, which is a hallmark ofcells undergoing apoptosis. Treatment of B16 cellsfor 24 h with phorbol 12-myristate 13-acetate ...

  4. Blockade of EGFR and MEK intercepts heterogeneous mechanisms of acquired resistance to anti-EGFR therapies in colorectal cancer.

    Science.gov (United States)

    Misale, Sandra; Arena, Sabrina; Lamba, Simona; Siravegna, Giulia; Lallo, Alice; Hobor, Sebastijan; Russo, Mariangela; Buscarino, Michela; Lazzari, Luca; Sartore-Bianchi, Andrea; Bencardino, Katia; Amatu, Alessio; Lauricella, Calogero; Valtorta, Emanuele; Siena, Salvatore; Di Nicolantonio, Federica; Bardelli, Alberto

    2014-02-19

    Colorectal cancers (CRCs) that are sensitive to the anti-epidermal growth factor receptor (EGFR) antibodies cetuximab or panitumumab almost always develop resistance within several months of initiating therapy. We report the emergence of polyclonal KRAS, NRAS, and BRAF mutations in CRC cells with acquired resistance to EGFR blockade. Regardless of the genetic alterations, resistant cells consistently displayed mitogen-activated protein kinase kinase (MEK) and extracellular signal-regulated kinase (ERK) activation, which persisted after EGFR blockade. Inhibition of MEK1/2 alone failed to impair the growth of resistant cells in vitro and in vivo. An RNA interference screen demonstrated that suppression of EGFR, together with silencing of MEK1/2, was required to hamper the proliferation of resistant cells. Indeed, concomitant pharmacological blockade of MEK and EGFR induced prolonged ERK inhibition and severely impaired the growth of resistant tumor cells. Heterogeneous and concomitant mutations in KRAS and NRAS were also detected in plasma samples from patients who developed resistance to anti-EGFR antibodies. A mouse xenotransplant from a CRC patient who responded and subsequently relapsed upon EGFR therapy showed exquisite sensitivity to combinatorial treatment with MEK and EGFR inhibitors. Collectively, these results identify genetically distinct mechanisms that mediate secondary resistance to anti-EGFR therapies, all of which reactivate ERK signaling. These observations provide a rational strategy to overcome the multifaceted clonal heterogeneity that emerges when tumors are treated with targeted agents. We propose that MEK inhibitors, in combination with cetuximab or panitumumab, should be tested in CRC patients who become refractory to anti-EGFR therapies.

  5. Protective Effect of Vitamins C and E on Depot-Medroxyprogesterone Acetate-Induced Ovarian Oxidative Stress In Vivo

    Directory of Open Access Journals (Sweden)

    Atik Ismiyati

    2016-01-01

    Full Text Available A study was designed to investigate ameliorates effect of combined vitamins C and E able to against depot-medroxyprogesterone acetate- (DMPA- induced ovarian oxidative stress in rat. Twenty-five female Wistar rats were divided into the following groups (n=5 rats each: control (untreated (C; depot-medroxyprogesterone acetate (DMPA; DMPA plus green vitamin C (at dose of 0.2 mg/gram; 0.4 mg/gram; 0.8 mg/gram and vitamin E (0.04 IU/gram. The treatment with combined vitamins C and E was performed for four weeks. Analysis of malondialdehyde (MDA level as a marker of oxidative stress was done colorimetrically. Analysis of SOD level was done by enzyme linked immunosorbent assay (ELISA technically. This increase in ovarium MDA was significantly (P<0.05 attenuated by medium dose treatments of combined vitamins C and E. DMPA insignificantly decreased SOD levels compared to the untreated group. This decrease in ovarian SOD level was significantly attenuated by all doses of the combined vitamins C and E. In conclusion, DMPA induces ovarian oxidative stress. Combined vitamins C and E prohibit the increase in ovarian lipid peroxidation, at least in part by modulating of superoxide dismutase. Therefore, this may provide an antioxidant therapy for attenuating the ovarian toxicity found in the DMPA therapy.

  6. Medroxyprogesterone Acetate Modulates Remodeling, Immune Cell Census, and Nerve Fibers in the Cervix of a Mouse Model for Inflammation-induced Preterm Birth

    OpenAIRE

    Yellon, Steven M.; Ebner, Charlotte A.; Elovitz, Michal A.

    2008-01-01

    To determine whether a progestational agent can modify inflammation-induced preterm cervical ripening, mice on day 15 of gestation were given an intrauterine injection of (1) saline, (2) lipopolysaccharide, (3) an intramuscular injection of medroxyprogesterone acetate alone prior to lipopolysaccharide, or (4) medroxyprogesterone acetate alone. Cervices were obtained 6 hours later, then fixed, sectioned, and processed to stain collagen structure or to identify immune cells or nerve fibers. Cer...

  7. Effects of different ligands on epidermal growth factor receptor (EGFR) nuclear translocation.

    Science.gov (United States)

    Faria, Jerusa A Q A; de Andrade, Carolina; Goes, Alfredo M; Rodrigues, Michele A; Gomes, Dawidson A

    2016-09-01

    The epidermal growth factor receptor (EGFR) is activated through binding to specific ligands and generates signals for proliferation, differentiation, migration, and cell survival. Recent data show the role of nuclear EGFR in tumors. Although many EGFR ligands are upregulated in cancers, little is known about their effects on EGFR nuclear translocation. We have compared the effects of six EGFR ligands (EGF, HB-EGF, TGF-α, β-Cellulin, amphiregulin, and epiregulin) on nuclear translocation of EGFR, receptor phosphorylation, migration, and proliferation. Cell fractionation and confocal immunofluorescence detected EGFR in the nucleus after EGF, HB-EGF, TGF-α and β-Cellulin stimulation in a dose-dependent manner. In contrast, amphiregulin and epiregulin did not generate nuclear translocation of EGFR. EGF, HB-EGF, TGF-α and β-Cellulin showed correlations between a higher rate of wound closure and increased phosphorylation of residues in the carboxy-terminus of EGFR, compared to amphiregulin and epiregulin. The data indicate that EGFR is translocated to the nucleus after stimulation with EGF, HB-EGF, TGF-α and β-Cellulin, and that these ligands are related to increased phosphorylation of EGFR tyrosine residues, inducing migration of SkHep-1 cells. PMID:27462018

  8. Effects of Lactobacillus plantarum TWK10-Fermented Soymilk on Deoxycorticosterone Acetate-Salt-Induced Hypertension and Associated Dementia in Rats.

    Science.gov (United States)

    Liu, Te-Hua; Chiou, Jiachi; Tsai, Tsung-Yu

    2016-01-01

    Oxidative stress resulting from excessive production of reactive oxygen species is the major mediator of neuronal cell degeneration observed in neurodegenerative diseases, such as Alzheimer's disease (AD) and vascular dementia (VaD). Additionally, hypertension has been shown to be a positive risk factor for VaD. Therefore, the objective of this study was to investigate the effects of Lactobacillus plantarum strain TWK10 (TWK10)-fermented soymilk on the protection of PC-12 cells in H₂O₂-, oxygen-glucose deprivation (OGD)- and deoxycorticosterone acetate (DOCA)-salt-induced rat models of VaD. Notably, the viabilities of H₂O₂-treated PC-12 cells and OGD model were significantly increased by treatment with TWK10-fermented soymilk ethanol extract (p memory in DOCA-salt hypertension-induced VaD rats by acting as a blood pressure-lowering and neuroprotective agent. PMID:27144579

  9. Response to the Dorsal Anterior Gradient of EGFR Signaling in Drosophila Oogenesis Is Prepatterned by Earlier Posterior EGFR Activation

    Directory of Open Access Journals (Sweden)

    Mariana Fregoso Lomas

    2013-08-01

    Full Text Available Spatially restricted epidermal growth factor receptor (EGFR activity plays a central role in patterning the follicular epithelium of the Drosophila ovary. In midoogenesis, localized EGFR activation is achieved by the graded dorsal anterior localization of its ligand, Gurken. Graded EGFR activity determines multiple dorsal anterior fates along the dorsal-ventral axis but cannot explain the sharp posterior limit of this domain. Here, we show that posterior follicle cells express the T-box transcription factors Midline and H15, which render cells unable to adopt a dorsal anterior fate in response to EGFR activation. The posterior expression of Midline and H15 is itself induced in early oogenesis by posteriorly localized EGFR signaling, defining a feedback loop in which early induction of Mid and H15 confers a molecular memory that fundamentally alters the outcome of later EGFR signaling. Spatial regulation of the EGFR pathway thus occurs both through localization of the ligand and through localized regulation of the cellular response.

  10. Nephroprotective effects of Zingiber zerumbet Smith ethyl acetate extract against paracetamol-induced nephrotoxicity and oxidative stress in rats

    Institute of Scientific and Technical Information of China (English)

    Zariyantey ABDUL HAMID; Siti Balkis BUDIN; Ng WEN JIE; Asmah HAMID; Khairana HUSAIN; Jamaludin MOHAMED

    2012-01-01

    Paracetamol (PCM) overdose can cause nephrotoxicity with oxidative stress as one of the possible mechanisms mediating the event.In this study,the effects of ethyl acetate extract of Zingiber zerunbet rhizome [200 mg per kg of body weight (mg/kg) and 400 mg/kg] on PCM-induced nephrotoxicity were examined.Rats were divided into five groups containing 10 rats each.The control group received distilled water while other groups were treated with extract alone (400 mg/kg),PCM alone (750 mg/kg),750 mg/kg PCM+200 mg/kg extract (PCM+200-extract),and 750 mg/kg PCM+400 mg/kg extract (PCM+400-extract),respectively,for seven consecutive days.The Z.zerumbet extract was given intraperitoneally concurrent with oral administration of PCM.Treatment with Z.zerumbet extract at doses of 200 and 400 mg/kg prevented the PCM-induced nephrotoxicity and oxidative impairments of the kidney,as evidenced by a significantly reduced (P<0.05) level of plasma creatinine,plasma and renal malondialdehyde (MDA),plasma protein carbonyl,and renal advanced oxidation protein product (AOPP).Furthermore both doses were also able to induce a significant increment (P<0.05) of plasma and renal levels of glutathione (GSH) and plasma superoxide dismutase (SOD) activity.The nephreprotective effects of Z.zerumbet extract were confirmed by a reduced intensity of renal cellular damage,as evidenced by histological findings.Moreover,Z.zerumbet extract administered at 400 mg/kg was found to show greater protective effects than that at 200 mg/kg.In conclusion,ethyl acetate extract of Z.zerumbet rhizome has a protective role against PCM-induced nephrotoxicity and the process is probably mediated through its antioxidant properties.

  11. Direct interaction between surface β1,4-galactosyltransferase 1 and epidermal growth factor receptor (EGFR) inhibits EGFR activation in hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Highlights: •β1,4GT1 interacts with EGFR both in vitro and in vivo. •β1,4GT1 co-localizes with EGFR on the cell surface. •β1,4GT1 inhibits 125I-EGF binding to EGFR. •β1,4GT1 inhibits EGF induced EGFR dimerization and phosphorylation. -- Abstract: Our previous studies showed that cell surface β1,4-galactosyltransferase 1 (β1,4GT1) negatively regulated cell survival through inhibition and modulation of the epidermal growth factor receptor (EGFR) signaling pathway in human hepatocellular carcinoma (HCC) SMMC-7721 cells. However, the underlying mechanism remains unclear. Here we demonstrated that β1,4-galactosyltransferase 1 (β1,4GT1) interacted with EGFR in vitro by GST pull-down analysis. Furthermore, we demonstrated that β1,4GT1 bound to EGFR in vivo by co-immunoprecipitation and determined the co-localization of β1,4GT1 and EGFR on the cell surface via confocal laser scanning microscopy analysis. Finally, using 125I-EGF binding experiments and Western blot analysis, we found that overexpression of β1,4GT1 inhibited 125I-EGF binding to EGFR, and consequently reduced the levels of EGFR dimerization and phosphorylation. In contrast, RNAi-mediated knockdown of β1,4GT1 increased the levels of EGFR dimerization and phosphorylation. These data suggest that cell surface β1,4GT1 interacts with EGFR and inhibits EGFR activation

  12. Quantum dot-based quantification revealed differences in subcellular localization of EGFR and E-cadherin between EGFR-TKI sensitive and insensitive cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Huang Donghai; Su Ling; Peng Xianghong; Zhang Hongzheng; Khuri, Fadlo R; Shin, Dong M; Chen Zhuo [Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA (United States)], E-mail: gzchen@emory.edu

    2009-06-03

    Nanoparticle quantum dots (QDs) provide sharper and more photostable fluorescent signals than organic dyes, allowing quantification of multiple biomarkers simultaneously. In this study, we quantified the expression of epidermal growth factor receptor (EGFR) and E-cadherin (E-cad) in the same cells simultaneously by using secondary antibody-conjugated QDs with two different emission wavelengths (QD605 and QD565) and compared the cellular distribution of EGFR and E-cad between EGFR-tyrosine kinase inhibitor (TKI)-insensitive and -sensitive lung and head and neck cancer cell lines. Relocalization of EGFR and E-cad upon treatment with the EGFR-TKI erlotinib in the presence of EGF was visualized and analyzed quantitatively. Our results showed that QD-immunocytochemistry (ICC)-based technology can not only quantify basal levels of multiple biomarkers but also track the localization of the biomarkers upon biostimulation. With this new technology we found that in EGFR-TKI-insensitive cells, EGFR and E-cad were located mainly in the cytoplasm; while in sensitive cells, they were found mainly on the cell membrane. After induction with EGF, both EGFR and E-cad internalized to the cytoplasm, but the internalization capability in sensitive cells was greater than that in insensitive cells. Quantification also showed that inhibition of EGF-induced EGFR and E-cad internalization by erlotinib in the sensitive cells was stronger than that in the insensitive cells. These studies demonstrate substantial differences between EGFR-TKI-insensitive and -sensitive cancer cells in EGFR and E-cad expression and localization both at the basal level and in response to EGF and erlotinib. QD-based analysis facilitates the understanding of the features of EGFR-TKI-insensitive versus -sensitive cancer cells and may be used in the prediction of patient response to EGFR-targeted therapy.

  13. Effect of Matricaria aurea (Loefl. Shultz-Bip. Hydroalcoholic Extract on Acetic Acid-Induced Acute Colitis in Rats

    Directory of Open Access Journals (Sweden)

    Mohsen Minaiyan

    Full Text Available Objective(s Matricaria aurea is found abundant in Iran and has large similarities in constituents especially essential oils, flavones and flavonoides as well as traditional uses to the main species; Matricaria recutita L. Anti-inflammatory, antioxidant and spasmolytic properties of the main species suggest that this plant may have beneficial effects on inflammatory bowel diseases so the present study was carried out.Materials and MethodsHydroalcoholic extract of plant with doses of 200, 400, 800 mg/kg were administered orally (p.o. for 5 days and rectally (i.r. (400 and 800 mg/kg at 15 and 2 hr before ulcer induction. To induce colitis, 2 ml of acetic acid 4% was instilled intra-colonically to separate groups of male Wistar rats (n= 6. Normal saline (2 ml, prednisolone (4 mg/kg and hydrocortisone acetate (20 mg/kg enema were administered to control and reference groups respectively. The tissue injures were assessed macroscopically and histopathologically. ResultsGreater doses of extract (400 and 800 mg/kg reduced colon weight/length ratio (P< 0.01 and the highest test dose (800 mg/kg p.o. or i.r. was effective to decrease tissue damage parameters including ulcer severity, area and index (P< 0.01 as well as inflammation severity and extent, crypt damage and total colitis index (P< 0.01 significantly. ConclusionIt is concluded that Matricaria aurea extract was effective to protect against acute colitis in acetic acid model and this effect was more significant with the greater doses administered orally or rectally. Further studies are warranted to ascertain the mechanisms that are involved and the responsible active constituents.

  14. Delphinidin reduces cell proliferation and induces apoptosis of non-small-cell lung cancer cells by targeting EGFR/VEGFR2 signaling pathways.

    Directory of Open Access Journals (Sweden)

    Harish Chandra Pal

    Full Text Available Epidermal growth factor receptor (EGFR and vascular endothelial growth factor receptor 2 (VEGFR2 have emerged as two effective clinical targets for non-small-cell lung cancer (NSCLC. In the present study, we found that delphinidin, an anthocyanidin, present in pigmented fruits and vegetables, is a potent inhibitor of both EGFR and VEGFR2 in NSCLC cells that overexpress EGFR/VEGFR2. Using these cells, we next determined the effects of delphinidin on cell growth and apoptosis in vitro and on tumor growth and angiogenesis in vivo. Delphinidin (5-60 µM treatment of NSCLC cells inhibited the activation of PI3K, and phosphorylation of AKT and MAPKs. Additionally, treatment of NSCLC cells with delphinidin resulted in inhibition of cell growth without having significant toxic effects on normal human bronchial epithelial cells. Specifically, treatment of NCI-H441 and SK-MES-1 cells with delphindin (5-60 µM resulted in (i cleavage of PARP protein, (ii activation of caspase-3 and -9, (iii downregulation of anti-apoptotic proteins (Bcl2, Bcl-xL and Mcl-1, (iv upregulation of pro-apoptotic proteins (Bax and Bak, and (v decreased expression of PCNA and cyclin D1. Furthermore, in athymic nude mice subcutaneously implanted with human NSCLC cells, delphinidin treatment caused a (i significant inhibition of tumor growth, (ii decrease in the expression of markers for cell proliferation (Ki67 and PCNA and angiogenesis (CD31 and VEGF, and (iii induction of apoptosis, when compared with control mice. Based on these observations, we suggest that delphinidin, alone or as an adjuvant to current therapies, could be used for the management of NSCLC, especially those that overexpress EGFR and VEGFR2.

  15. Trenbolone acetate induced changes in the genital tract of male pigs.

    Science.gov (United States)

    López-Bote, C; Sancho, G; Martínez, M; Ventanas, J; Gázquez, A; Roncero, V

    1994-03-01

    Eleven entire and twelve castrated male pigs were implanted with trenbolone acetate and the effects of the treatment on genital tract macro- and microscopical modifications were evaluated and compared to non-implanted animals. In entire male pigs a reduction of testicular weight and size was observed as a consequence of the treatment (< 0.001), but no important modifications were found in bulbourethral gland and seminal vesicles macroscopically. Castrated non-implanted males had bulbourethral gland atrophy (P < 0.01), while castrated implanted ones showed similar development to entire males. As for vesicular glands there were no significant differences among the four groups under study. Histological study of prostate has demonstrated structural modifications. As a consequence of the treatment glandular lumen was increased (P < 0.05), and most parenchyma was occupied by polymorphous cysts.

  16. Neurotransmitter chemistry of lissencephalic cortex induced in ferrets by fetal treatment with methylazoxymethanol acetate.

    Science.gov (United States)

    Johnston, M V; Haddad, R; Carman-Young, A; Coyle, J T

    1982-07-01

    Treatment of pregnant ferrets with 15 mg/kg of methylazoxymethanol acetate (MAM) at 33 days of fetal gestation results in offspring with cortical hypoplasia and lissencephally. Neurochemical analysis of 5 areas of cortex from 8-week-old offspring of MAM- or vehicle-treated jills indicated an overall enrichment in markers for catecholaminergic (tyrosine hydroxylase, norepinephrine) and cholinergic (choline acetyltransferase, acetylcholine) terminals but minimal change in the concentration of GABAergic markers (glutamate decarboxylase, gamma-aminobutyric acid); however, there did not appear to be a direct, inverse relationship between the concentration of catecholaminergic and cholinergic markers and the degree of hypoplasia in cortical subareas unlike what has been found previously in the rat. PMID:6125249

  17. Ezrin Enhances EGFR Signaling and Modulates Erlotinib Sensitivity in Non–Small Cell Lung Cancer Cells

    Directory of Open Access Journals (Sweden)

    Yasemin Saygideğer-Kont

    2016-02-01

    Full Text Available Ezrin is a scaffolding protein that is involved in oncogenesis by linking cytoskeletal and membrane proteins. Ezrin interacts with epidermal growth factor receptor (EGFR in the cell membrane, but little is known about the effects of this interaction on EGFR signaling pathway. In this study, we established the biological and functional significance of ezrin-EGFR interaction in non–small cell lung cancer (NSCLC cells. Endogenous ezrin and EGRF interaction was confirmed by co-immunoprecipitation and immunofluorescent staining. When expression of ezrin was inhibited, EGFR activity and phosphorylation levels of downstream signaling pathway proteins ERK and STAT3 were decreased. Cell fractionation experiments revealed that nuclear EGFR was significantly diminished in ezrin-knockdown cells. Consequently, mRNA levels of EGFR target genes AURKA, COX-2, cyclin D1, and iNOS were decreased in ezrin-depleted cells. A small molecule inhibitor of ezrin, NSC305787, reduced EGF-induced phosphorylation of EGFR and downstream target proteins, EGFR nuclear translocation, and mRNA levels of nuclear EGFR target genes similar to ezrin suppression. NSC305787 showed synergism with erlotinib in wild-type EGFR-expressing NSCLC cells, whereas no synergy was observed in EGFR-null cells. Phosphorylation of ezrin on Y146 was found as an enhancer of ezrin-EGFR interaction and required for increased proliferation, colony formation, and drug resistance to erlotinib. These findings suggest that ezrin-EGFR interaction augments oncogenic functions of EGFR and that targeting ezrin may provide a potential novel approach to overcome erlotinib resistance in NSCLC cells.

  18. Effects of the EGFR Inhibitor Erlotinib on Magnesium Handling

    DEFF Research Database (Denmark)

    Dimke, Henrik Anthony; van der Wijst, Jenny; Alexander, Todd R;

    2010-01-01

    A mutation in pro-EGF causes isolated hypomagnesemia, and monoclonal antibodies targeting the extracellular domain of the EGF receptor (EGFR) affect epithelial Mg(2+) transport. The effect of the EGFR tyrosine kinase inhibitor erlotinib on Mg(2+) homeostasis, however, remains unknown. Here, we...... in renal expression of transient receptor potential melastatin 6 (TRPM6) protein, the channel that mediates Mg(2+) reabsorption. Patch clamp analysis in TRPM6-expressing cells demonstrated that 30 muM erlotinib inhibited EGF-induced changes in TRPM6 current density and tyrosine phosphorylation of EGFR; 0...... that observed with antibody-based EGFR inhibitors. These data suggest that typical human dosages of erlotinib are unlikely to severely affect serum Mg(2+) concentrations....

  19. Akt kinase-interacting protein1, a novel therapeutic target for lung cancer with EGFR-activating and gatekeeper mutations.

    Science.gov (United States)

    Yamada, T; Takeuchi, S; Fujita, N; Nakamura, A; Wang, W; Li, Q; Oda, M; Mitsudomi, T; Yatabe, Y; Sekido, Y; Yoshida, J; Higashiyama, M; Noguchi, M; Uehara, H; Nishioka, Y; Sone, S; Yano, S

    2013-09-12

    Despite initial dramatic response, epidermal growth factor receptor (EGFR) mutant lung cancer patients always acquire resistance to EGFR-tyrosine kinase inhibitors (TKIs). Gatekeeper T790M mutation in EGFR is the most prevalent genetic alteration underlying acquired resistance to EGFR-TKI, and EGFR mutant lung cancer cells are reported to be addictive to EGFR/Akt signaling even after acquired T790M mutation. Here, we focused on Akt kinase-interacting protein1 (Aki1), a scaffold protein of PI3K (phosphoinositide 3-kinase)/PDK1 (3-phosphoinositide-dependent protein kinase)/Akt that determines receptor signal selectivity for non-mutated EGFR, and assessed its role in EGFR mutant lung cancer with or without gatekeeper T790M mutation. Cell line-based assays showed that Aki1 constitutively associates with mutant EGFR in lung cancer cells with (H1975) or without (PC-9 and HCC827) T790M gatekeeper mutation. Silencing of Aki1 induced apoptosis of EGFR mutant lung cancer cells. Treatment with Aki1 siRNA dramatically inhibited growth of H1975 cells in a xenograft model. Moreover, silencing of Aki1 further potentiated growth inhibitory effect of new generation EGFR-TKIs against H1975 cells in vitro. Aki1 was frequently expressed in tumor cells of EGFR mutant lung cancer patients (53/56 cases), including those with acquired resistance to EGFR-TKI treatment (7/7 cases). Our data suggest that Aki1 may be a critical mediator of survival signaling from mutant EGFR to Akt, and may therefore be an ideal target for EGFR mutant lung cancer patients, especially those with acquired EGFR-TKI resistance due to EGFR T790M gatekeeper mutation. PMID:23045273

  20. UV RADIATION INDUCED GRAFT COPOLYMERIZATION OF ALLYL ACETATE ONTO POLY(ETHYLENE TEREPHTHALATE) (PET) FILMS FOR FUEL CELL MEMBRANES

    Institute of Scientific and Technical Information of China (English)

    Mostak Ahmed; Mubarak A. Khan; Nazia Rahman; M. Anwar H. Khan

    2012-01-01

    Ultraviolet (UV)-induced graft copolymerization of allyl acetate (AA) monomer onto poly(ethylene terephthalate) (PET) films and the subsequent sulfonation on the monomer units in the grafting chain using chlorosulfonic acid (C1SO3H) were carried out to prepare proton exchange membranes (PEMs) for fuel cells.A maximum grafting value of 12.8% was found for 35 vol% allyl acetate after 3 h radiation time.Optimum concentration of ClSO3H was selected for the sulfonation reaction to be 0.05 mol/L based on the degree of sulfonation and the tensile strength studies of the membrane.The degree of sulfonation increased as the sulfonation reaction temperature and sulfonation time were increasing.The radiation grafting and the sulfonation have been confirmed by titrimetric and gravimetric analyses as well as FTIR spectroscopy.The maximum ion exchange capacity (IEC) of 0.04125 mmol g-1 was found at 12.1% degree of sulfonation and the maximum proton conductivity was found to be 0.035 S cm-1 at 30℃ and a relative humidity of 60%.The various physical and chemical properties of the PEMs such as water uptake,mechanical strength,thermal durability and oxidative stability were also studied.To investigate the suitability of the prepared membrane for fuel cell applications,its properties were compared with those of Nation 117.

  1. Expression of epidermal growth factor receptor (EGFR) and activated EGFR predict poor response to (chemo)radiation and survival in cervical cancer

    NARCIS (Netherlands)

    Noordhuis, M.G.; Eijsink, J.J.H.; ten Hoor, K.A.; Roossink, F.; Hollema, H.; Arts, H.J.G.; Pras, Elisabeth; Maduro, John; Reyners, A.K.L.; de Bock, G.H.; Wisman, G.B.A.; Schuuring, E.; van der Zee, A.G.J.

    2009-01-01

    PURPOSE: Activation of the epidermal growth factor receptor (EGFR) signaling pathway has been reported to induce resistance to (chemo)radiation in cancers, such as head and neck cancer, whereas EGFR-targeted agents in combination with (chemo)radiation seem to improve treatment efficacy. The aim of t

  2. Selective Antitumor Activity of Ibrutinib in EGFR-Mutant Non–Small Cell Lung Cancer Cells

    OpenAIRE

    Gao, Wen; Wang, Michael; Wang, Li; Lu, Haibo; Wu, Shuhong; Dai, Bingbing; Ou, Zhishuo; Zhang, Liang; Heymach, John V.; Gold, Kathryn A.; Minna, John ,; Roth, Jack A.; Hofstetter, Wayne L.; Swisher, Stephen G.; Fang, Bingliang

    2014-01-01

    Ibrutinib, which irreversibly inhibits Bruton tyrosine kinase, was evaluated for antitumor activity in a panel of non–small cell lung cancer (NSCLC) cell lines and found to selectively inhibit growth of NSCLC cells carrying mutations in the epidermal growth factor receptor (EGFR) gene, including T790M mutant and erlotinib-resistant H1975 cells. Ibrutinib induced dose-dependent inhibition of phosphor-EGFR at both Y1068 and Y1173 sites, suggesting ibrutinib functions as an EGFR inhibitor. Survi...

  3. Prophylactic Tetracycline Does Not Diminish the Severity of Epidermal Growth Factor Receptor (EGFR) Inhibitor Induced Rash: Results from the North Central Cancer Treatment Group (Supplementary N03CB)1

    Science.gov (United States)

    Jatoi, Aminah; Dakhil, Shaker R.; Sloan, Jeff A.; Kugler, John W.; Rowland, Kendrith M.; Schaefer, Paul L.; Novotny, Paul J.; Wender, Donald B.; Gross, Howard M.; Loprinzi, Charles L.

    2014-01-01

    PURPOSE Previous studies suggest tetracycline and other antibiotics lessen the severity of epidermal growth factor receptor (EGFR) inhibitor-induced rash. This study sought to confirm such findings. METHODS Patients starting an EGFR inhibitor were eligible for this randomized, double-blinded, placebo-controlled study and had to be rash-free. They were then randomly assigned to tetracycline 500 milligrams orally twice a day for 28 days versus a placebo. Rash development and severity (monthly physician assessment and weekly patient-reported questionnaires), quality of life (SKINDEX-16), and adverse events were monitored during the 4-week intervention and then for an additional 4 weeks. The primary objective was to compare the incidence of grade 2 or worse rash between study arms; 32 patients per group provided a 90% probability of detecting a 40% difference in incidence with a type I error rate of 0.05 (2-sided). RESULTS 65 patients were enrolled, and groups were balanced on baseline characteristics. During the first 4 weeks, healthcare provider-reported data found that 27 tetracycline-treated patients (82%) and 24 placebo-exposed patients (75%) developed a rash. This rash was a grade 2+ in 17 (52%) and 14 (44%), respectively (p=0.62). Comparable grade 2+ rash rates were observed during weeks 5 through 8 as well as with patient-reported rash data throughout the study period. Quality of life was comparable across study arms, and tetracycline was well tolerated. CONCLUSION Although previous studies suggest otherwise, this randomized, double-blinded, placebo-controlled did not find that tetracycline lessened rash incidence or severity in patients who were taking EGFR inhibitors. PMID:20820817

  4. Podophyllotoxin acetate blocks IR-induced invasion of non-small cell lung cancer cell, A549

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jeong Hyun; Choi, Jae Yeon; Hwang, Sang-Gu; Um, Hong-Duck; Park, Jong Kuk [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2015-05-15

    Some research result presented that local radiotherapy administered to primary tumors speeds their metastatic growth in vivo (4-6), thereby suggesting that besides its therapeutic effects, IR promotes the malignant behaviors of surviving cancer cells. Our findings demonstrate podophyllotoxin acetate (PA), one of new natural products, prevented side effects of IR such as invasion or metastasis promotion for improve the efficacy of radiotherapy. In this study, we demonstrated that PA inhibits IR-induced invasion and migration of A549 cells. We also observed that IR stimulates several intracellular pathway involving EMT and MAPKinses; EMT-associated events including an increase of vimentin levels and increased phosphorylation of p38 ERK, JNK in A549 cells. PA could decrease these activations of several intracellular signaling molecules. Therefore, PA might inhibit IRinduced invasion and migration via blocking EMT and MAPKiase pathway of A549 cells.

  5. Role of water in chromosome spreading and swelling induced by acetic acid treatment: a FTIR spectroscopy study

    Directory of Open Access Journals (Sweden)

    D. Ami

    2014-02-01

    Full Text Available The so called chromosome preparation is a procedure consisting of three strictly connected stages that enables to obtain chromosomes of quality suitable for cytogenetic analysis. Interestingly, experimental evidence strongly suggested that chromosome spreading and swelling (key processes that allow their counting and detailed structural analysis are induced in the last fixative-evaporation stage by the interaction, mediated by acetic acid, between water from the environmental humidity, and the cytoplasmic matrix and the chromatin. However, since a considerable variation in the quality of chromosome preparations is observed, strongly depending on the environmental conditions in which the procedure takes place, a better comprehension of the mechanisms underlying chromosome preparation is required. To this aim, here we analysed intact lymphocytes before and at each stage of the chromosome preparation protocol by Fourier transform infrared (FTIR spectroscopy, a technique widely used for the study not only of isolated biomolecules, but also of complex biological systems, such as whole cells. Interestingly, we found that the chromosome preparation protocol induces significant structural changes of cell proteins and DNA, in particular due to the interaction with acetic acid. Moreover, noteworthy, through the monitoring of changes in the water combination band between 2300 and 1800 cm–1, we provided evidence at molecular level of the crucial role of the bound water to the cytoplasmic matrix and to the chromatin in determining the chromosome spreading and swelling. Our FTIR results, therefore, underline the need to perform the last fixative-evaporation stage in standardized and optimized temperature and relative humidity conditions, thus providing chromosomes of high quality for the cytogenetic analysis that would lead in this way to more reliable results.

  6. Nutrient salts promote light-induced degradation of indole-3-acetic Acid in tissue culture media.

    Science.gov (United States)

    Dunlap, J R; Robacker, K M

    1988-10-01

    The disappearance of indole-3-acetic acid (IAA) from cell-free liquid culture medium was followed in response to nutrient salts found in Murashige-Skoog salt base, light, and pH range of 4 to 7. The loss of IAA was accelerated by light or Murashige-Skoog salts. However, the combination of both light and Murashige-Skoog salts acted synergistically to catalyze the destruction of over 80% of the original IAA within 7 days of continuous incubation. Under these same conditions, the loss of IAA was decreased to approximately 50% by adjusting the initial pH of the medium to 7. Iron was identified as the single major contributor to light-catalyzed destruction of IAA. Removal of nitrates, which represented 87% of the molar salt composition, also reduced the light-catalyzed loss of IAA. Treatments that protected IAA from degradation, such as darkness or removal of iron from the medium, suppressed the growth of muskmelon (Cucumis melo. Naud., var. reticulatus) callus tissue cultured for 30 days. Treatments in the light that rapidly degraded IAA resulted in maximum growth. Consequently, the brief exposure to IAA prior to degradation was apparently sufficient to initiate physiological changes required for growth. Possible approaches to the preservation of IAA during incubation are discussed. PMID:16666312

  7. Epidermal growth factor receptor (EGFR) mutations in lung cancer: preclinical and clinical data

    Energy Technology Data Exchange (ETDEWEB)

    Jorge, S.E.D.C.; Kobayashi, S.S.; Costa, D.B. [Harvard Medical School, Beth Israel Deaconess Medical Center, Department of Medicine, Division of Hematology/Oncology, Boston, MA (United States)

    2014-09-05

    Lung cancer leads cancer-related mortality worldwide. Non-small-cell lung cancer (NSCLC), the most prevalent subtype of this recalcitrant cancer, is usually diagnosed at advanced stages, and available systemic therapies are mostly palliative. The probing of the NSCLC kinome has identified numerous nonoverlapping driver genomic events, including epidermal growth factor receptor (EGFR) gene mutations. This review provides a synopsis of preclinical and clinical data on EGFR mutated NSCLC and EGFR tyrosine kinase inhibitors (TKIs). Classic somatic EGFR kinase domain mutations (such as L858R and exon 19 deletions) make tumors addicted to their signaling cascades and generate a therapeutic window for the use of ATP-mimetic EGFR TKIs. The latter inhibit these kinases and their downstream effectors, and induce apoptosis in preclinical models. The aforementioned EGFR mutations are stout predictors of response and augmentation of progression-free survival when gefitinib, erlotinib, and afatinib are used for patients with advanced NSCLC. The benefits associated with these EGFR TKIs are limited by the mechanisms of tumor resistance, such as the gatekeeper EGFR-T790M mutation, and bypass activation of signaling cascades. Ongoing preclinical efforts for treating resistance have started to translate into patient care (including clinical trials of the covalent EGFR-T790M TKIs AZD9291 and CO-1686) and hold promise to further boost the median survival of patients with EGFR mutated NSCLC.

  8. Treatment of mouse melanoma cells with phorbol 12-myristate 13-acetate counteracts mannosylerythritol lipid-induced growth arrest and apoptosis.

    Science.gov (United States)

    Zhao, X; Geltinger, C; Kishikawa, S; Ohshima, K; Murata, T; Nomura, N; Nakahara, T; Yokoyama, K K

    2000-07-01

    Mannosylerythritol lipid (MEL), an extracellularglycolipid from yeast, induces the differentiation ofHL-60 promyelocytic leukemia cells towardsgranulocytes. We show here that MEL is also a potentinhibitor of the proliferation of mouse melanoma B16cells. Flow-cytometric analysis of the cell cycle ofMEL-treated B16 cells revealed the accumulation ofcells in the sub-G(0)/G(1) phase, which is a hallmark ofcells undergoing apoptosis. Treatment of B16 cellsfor 24 h with phorbol 12-myristate 13-acetate (PMA),an activator of protein kinase C (PKC), did notinterfere with the growth and survival of the cells,but it effectively counteracted the MEL-induced growtharrest and apoptosis. The activity of PKC was reducedin B16 cells treated with MEL at a concentration atwhich MEL induced apoptosis. However, incubation withPMA in addition to MEL reversed this reduction in theactivity of PKC. These results suggest thatconverging signaling pathways are triggeredindependently by MEL and PMA and that the signalsmight both be mediated by PKC. PMID:19002819

  9. Effects of Lactobacillus plantarum TWK10-Fermented Soymilk on Deoxycorticosterone Acetate-Salt-Induced Hypertension and Associated Dementia in Rats

    Directory of Open Access Journals (Sweden)

    Te-Hua Liu

    2016-05-01

    Full Text Available Oxidative stress resulting from excessive production of reactive oxygen species is the major mediator of neuronal cell degeneration observed in neurodegenerative diseases, such as Alzheimer’s disease (AD and vascular dementia (VaD. Additionally, hypertension has been shown to be a positive risk factor for VaD. Therefore, the objective of this study was to investigate the effects of Lactobacillus plantarum strain TWK10 (TWK10-fermented soymilk on the protection of PC-12 cells in H2O2-, oxygen-glucose deprivation (OGD- and deoxycorticosterone acetate (DOCA-salt-induced rat models of VaD. Notably, the viabilities of H2O2-treated PC-12 cells and OGD model were significantly increased by treatment with TWK10-fermented soymilk ethanol extract (p < 0.05. In addition, oral administration of TWK10-fermented soymilk extract in DOCA-salt hypertension-induced VaD rats resulted in a significant decrease in blood pressure (p < 0.05, which was regulated by inhibiting ACE activity and promoting NO production, in addition to decreased escape latency and increased target crossing (p < 0.05. In conclusion, these results demonstrated that TWK10-fermented soymilk extract could improve learning and memory in DOCA-salt hypertension-induced VaD rats by acting as a blood pressure-lowering and neuroprotective agent.

  10. Testosterone undecanoate and depo medroxyprogesterone acetate induced azoospermia through increased expression of spermatogenic cell caspase 3

    Directory of Open Access Journals (Sweden)

    Nukman Moeloek

    2008-09-01

    Full Text Available The administration of a combination of testosterone undecanoate (TU, a long-acting androgen and depo-medroxyprogesterone acetate (DMPA were investigated in term of suppression of rat sperm concentration in vivo to azoospermia through increasing activity of spermatogenic cell caspase 3. Adult Sprague Dawley rats received TU and DMPA of 2.5 mg and 1.25 mg, respectively, a regimen known to rapidly reduce intra testicular testosterone and to produce azoospermia within 12 weeks. Caspase 3 positive sperm cells increased compared with control levels during 6 weeks post-injection and increased further through 60 weeks. Immunohistochemistry for caspase 3 revealed that spermatocytes represented the predominant caspase 3 positive germ cells. Modest immunoreactivity for caspase-3 was localized to nuclear region of the germ cells of control and treated testes. Immunohistochemistry study revealed significantly increased caspase-3 expression in nuclei of germ cells during administration of TU+DMPA to rats. Additionally, the caspase 3 content was significantly increased in germ cells during rats were administered TU+DMPA (453.90±84.88 cells/200 seminiferous tubules and caspase 3 significant increase in immunoreactivity was localized to the nuclei of spermatogonia, spermatocytes, and spermatids. Taken together, these results indicated that azoospermia due to reduced intratesticular testosterone concentration was caspase-3 activation dependent and suggested that the increase in active caspase-3 in the nucleus may be involved in the induction of decreased sperm production. (Med J Indones 2008; 17: 149-56Keywords: TU, DMPA, sperm concentration, germ cells

  11. Exposure to gamma-irradiation increases phorbol myristate acetate-induced H2O2 production in human macrophages

    International Nuclear Information System (INIS)

    Cell number, protein, and phorbol myristate acetate (PMA)-induced H2O2 production were measured in cultured human peripheral blood monocytes for six days after exposure to varying doses of gamma-radiation. Both the number of adherent cells and the protein per dish decreased with increasing radiation doses. The dose of radiation decreasing the number of adherent cells by 37% on days 4 and 6 postirradiation was 29 Gy. Four hours postirradiation there was a small decrease in PMA-induced H2O2 production for doses of 7.5 Gy or greater; levels returned to normal by eight hours and increased at 24 hours postirradiation. By day 4 postirradiation significant increases in PMA-induced H2O2 production were noted at all radiation doses (2.5 to 50 Gy). This increase was not due to a shift in the PMA dose-response curve, a change in the time course of the PMA response, or an effect of decreased cell density on the assay system. Superoxide levels were not significantly changed in cells exposed to 20 Gy. Catalase, glutathione peroxidase, and superoxide dismutase levels also were unchanged. Culturing irradiated cells with gamma-interferon increased PMA-induced H2O2 release, which indicated that irradiated cells retained their capacity to respond to gamma-interferon. These data demonstrate that irradiation affects the PMA-induced H2O2 production of human monocytes in a time- and dose-dependent manner. An increase in the release of reactive oxygen intermediates by the macrophage may play a role in enhancing the deleterious effects of radiation in vivo

  12. Protective effects of alisol B 23-acetate from edible botanical Rhizoma alismatis against carbon tetrachloride-induced hepatotoxicity in mice.

    Science.gov (United States)

    Meng, Qiang; Chen, Xinli; Wang, Changyuan; Liu, Qi; Sun, Huijun; Sun, Pengyuan; Huo, Xiaokui; Liu, Zhihao; Liu, Kexin

    2015-04-01

    Carbon tetrachloride (CCl4)-induced hepatotoxicity is a common syndrome with simultaneous severe hepatocyte death and acute cholestasis. The purpose of the present study is to investigate the hepatoprotective effect of alisol B 23-acetate (AB23A), a natural triterpenoid from edible botanical Rhizoma alismatis, on acute hepatotoxicity induced by CCl4 in mice, and further to elucidate the involvement of farnesoid X receptor (FXR), signal transducers and activators of transcription 3 (STAT3) in the hepatoprotective effect. H&E staining, BrdU immunohistochemistry and TUNEL assay were used to identify the amelioration of histopathological changes, hepatocyte proliferation and apoptosis. Real-time PCR and western blot assay were used to elucidate the mechanisms underlying AB23A hepatoprotection. The results indicated that AB23A treatment in a dose-dependent manner resulted in protection against hepatotoxicity induced by CCl4via FXR activation. Through FXR activation, AB23A promoted hepatocyte proliferation via an induction in hepatic levels of FoxM1b, Cyclin D1 and Cyclin B1. AB23A also reduced hepatic bile acids through a decrease in hepatic uptake transporter Ntcp, bile acid synthetic enzymes Cyp7a1, Cyp8b1, and an increase in efflux transporter Bsep, Mrp2 expression. In addition, AB23A induced the expression of STAT3 phosphorylation, and STAT3 target genes Bcl-xl and SOCS3, resulting in decreased hepatocyte apoptosis. In conclusion, AB23A produces a protective effect against CCl4-induced hepatotoxicity, due to FXR and STAT3-mediated gene regulation. PMID:25747392

  13. EGFR-Targeting as a Biological Therapy: Understanding Nimotuzumab's Clinical Effects

    Energy Technology Data Exchange (ETDEWEB)

    Perez, Rolando, E-mail: rolando@cim.sld.cu; Moreno, Ernesto; Garrido, Greta; Crombet, Tania [Center of Molecular Immunology, P.O. Box 16040, Havana 11600 (Cuba)

    2011-04-18

    Current clinical trials of epidermal growth factor receptor (EGFR)-targeted therapies are mostly guided by a classical approach coming from the cytotoxic paradigm. The predominant view is that the efficacy of EGFR antagonists correlates with skin rash toxicity and induction of objective clinical response. Clinical benefit from EGFR-targeted therapies is well documented; however, chronic use in advanced cancer patients has been limited due to cumulative and chemotherapy-enhanced toxicity. Here we analyze different pieces of data from mechanistic and clinical studies with the anti-EGFR monoclonal antibody Nimotuzumab, which provides several clues to understand how this antibody may induce a biological control of tumor growth while keeping a low toxicity profile. Based on these results and the current state of the art on EGFR-targeted therapies, we discuss the need to evaluate new therapeutic approaches using anti-EGFR agents, which would have the potential of transforming advanced cancer into a long-term controlled chronic disease.

  14. Analysis list: EGFR [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available EGFR Uterus + hg19 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/EGFR.1.ts...v http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/EGFR.5.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/target/EGFR....10.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/EGFR.Uterus.tsv http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/colo/Uterus.gml ...

  15. Anti-inflammatory effect of Moringa oleifera Lam. seeds on acetic acid-induced acute colitis in rats

    Directory of Open Access Journals (Sweden)

    Mohsen Minaiyan

    2014-02-01

    Full Text Available Objective: Anti-inflammatory, immuno-modulatory, and antioxidant properties of Moringa oleifera Lam. suggest that it might have beneficial effects on colitis. The present study was performed to investigate the anticolitis effect of Moringa oleifera seeds hydro-alcoholic extract (MSHE and its chloroform fraction (MCF on acetic acid-induced colitis in rats. Materials and Methods: Both MSHE and MCF with three increasing doses (50, 100, and 200 mg/kg were administered orally to separate groups of male Wistar rats, 2 h before ulcer induction (using acetic acid 4% and continued for 5 days. Prednisolone (4 mg/kg and normal saline (1 ml/kg were used in reference and control groups, respectively. All rats were sacrificed 24 h after the last dose (at day 6 and tissue injuries were assessed macroscopically and pathologically. Results: Extracts with three doses mentioned before were effective to reduce weight of distal colon (8 cm as a marker for inflammation and tissue edema. Three doses of MSHE and two greater doses of MCF (100 and 200 mg/kg were effective to reduce ulcer severity, area, and index as well as mucosal inflammation severity and extent, crypt damage, invasion involvement, total colitis index, and MPO activity compared with controls. MCF (50 mg/kg was not significantly effective in reducing evaluated parameters of colitis compared with controls. Conclusion: It is concluded that MSHE and MCF were both effective to treat experimental colitis and this might be attributed to their similar major components, biophenols and flavonoids. Since the efficacy was evident even in low doses of MSHE, presence of active constituents with high potency in seeds is persuasive.

  16. Apoptosis of pancreatic cancer BXPC-3 cells induced by indole-3-acetic acid in combination with horseradish peroxidase

    Institute of Scientific and Technical Information of China (English)

    Chen Huang; Lu-Sheng Si; Li-Ying Liu; Tu-Sheng Song; Lei Ni; Ling Yang; Xiao-Yan Hu; Jing-Song Hu; Li-Ping Song; Yu Luo

    2005-01-01

    AIM: To explore the mechanisms underlying the apoptosis of human pancreatic cancer BXPC-3 cells induced by indole-3-acetic acid (TAA) in combination with horseradish peroxidase (HRP).METHODS: BXPC-3 cells derived from human pancreatic cancer were exposed to 40 or 80 μmol/L IAA and 1.2 μg/mL HRP at different times. Then, MTT assay was used to detect the cell proliferation. Flow cytometry was performed to analyze cell cycle. Terminal deoxynucleotidyl transferasemediated dUTP nick end labeling assay was used to detect apoptosis. 2,7-Dichlorofluorescin diacetate uptake was measured by confocal microscopy to determine free radicals. Level of malondialdehyde (MDA) and activity of superoxide dismutase (SOD) were measured by biochemical methods.RESULTS: IAA/HRP initiated growth inhibition of BXPC-3 cells in a dose- and time-dependent manner. Flow cytometry revealed that the cells treated for 48 h were arrested at G1/G0. After exposure to 80 μmol/L IAA plus 1.2 μg/mL HRP for 72 h, the apoptosis rate increased to 72.5‰,which was nine times that of control. Content of MDA and activity of SOD increased respectively after treatment compared to control. Meanwhile, IAA/HRP stimulated the formation of free radicals.CONCLUSION: The combination of IAA and HRP can inhibit the growth of human pancreatic cancer BXPC-3 cells in vitro by inducing apoptosis.

  17. Indole-3-acetic acid-induced oxidative burst and an increase in cytosolic calcium ion concentration in rice suspension culture.

    Science.gov (United States)

    Nguyen, Hieu T H; Umemura, Kenji; Kawano, Tomonori

    2016-08-01

    Indole-3-acetic acid (IAA) is the major natural auxin involved in the regulation of a variety of growth and developmental processes such as division, elongation, and polarity determination in growing plant cells. It has been shown that dividing and/or elongating plant cells accompanies the generation of reactive oxygen species (ROS) and a number of reports have suggested that hormonal actions can be mediated by ROS through ROS-mediated opening of ion channels. Here, we surveyed the link between the action of IAA, oxidative burst, and calcium channel activation in a transgenic cells of rice expressing aequorin in the cytosol. Application of IAA to the cells induced a rapid and transient generation of superoxide which was followed by a transient increase in cytosolic Ca(2+) concentration ([Ca(2+)]c). The IAA-induced [Ca(2+)]c elevation was inhibited by Ca(2+) channel blockers and a Ca(2+) chelator. Furthermore, ROS scavengers effectively blocked the action of IAA on [Ca(2+)]c elevation. PMID:27149194

  18. Antibody-targeted horseradish peroxidase associated with indole-3-acetic acid induces apoptosis in vitro in hematological malignancies.

    Science.gov (United States)

    Dalmazzo, Leandro F F; Santana-Lemos, Bárbara A; Jácomo, Rafael H; Garcia, Aglair B; Rego, Eduardo M; da Fonseca, Luiz M; Falcão, Roberto P

    2011-05-01

    Indole-3-acetic acid (IAA), when oxidized by horseradish peroxidase (HRP), is transformed into cytotoxic molecules capable of inducing cell injury. The aim of this study was to test if, by targeting hematopoietic tumors with HRP-conjugated antibodies in association with IAA treatment, there is induction of apoptosis. We used two lineages of hematologic tumors: NB4, derived from acute promyelocytic leukemia (APL) and Granta-519 from mantle cell lymphoma (MCL). We also tested cells from 12 patients with acute myeloid leukemia (AML) and from 10 patients with chronic lymphocytic leukemia (CLL). HRP targeting was performed with anti-CD33 or anti-CD19 antibodies (depending on the origin of the cell), followed by incubation with goat anti-mouse antibody conjugated with HRP. Eight experimental groups were analyzed: control, HRP targeted, HRP targeted and incubated with 1, 5 and 10mM IAA, and cells not HRP targeted but incubated with 1, 5 and 10mM IAA. Apoptosis was analyzed by flow cytometry using annexin V-FITC and propidium iodide labeling. Results showed that apoptosis was dependent on the dose of IAA utilized, the duration of exposure to the prodrug and the origin of the neoplasia. Targeting HRP with antibodies was efficient in activating IAA and inducing apoptosis. PMID:21168913

  19. DUOX1 mediates persistent epithelial EGFR activation, mucous cell metaplasia, and airway remodeling during allergic asthma

    Science.gov (United States)

    Habibovic, Aida; Hristova, Milena; Heppner, David E.; Danyal, Karamatullah; Ather, Jennifer L.; Janssen-Heininger, Yvonne M.W.; Irvin, Charles G.; Poynter, Matthew E.; Lundblad, Lennart K.; Dixon, Anne E.; Geiszt, Miklos

    2016-01-01

    Chronic inflammation with mucous metaplasia and airway remodeling are hallmarks of allergic asthma, and these outcomes have been associated with enhanced expression and activation of EGFR signaling. Here, we demonstrate enhanced expression of EGFR ligands such as amphiregulin as well as constitutive EGFR activation in cultured nasal epithelial cells from asthmatic subjects compared with nonasthmatic controls and in lung tissues of mice during house dust mite–induced (HDM-induced) allergic inflammation. EGFR activation was associated with cysteine oxidation within EGFR and the nonreceptor tyrosine kinase Src, and both amphiregulin production and oxidative EGFR activation were diminished by pharmacologic or genetic inhibition of the epithelial NADPH oxidase dual oxidase 1 (DUOX1). DUOX1 deficiency also attenuated several EGFR-dependent features of HDM-induced allergic airway inflammation, including neutrophilic inflammation, type 2 cytokine production (IL-33, IL-13), mucous metaplasia, subepithelial fibrosis, and central airway resistance. Moreover, targeted inhibition of airway DUOX1 in mice with previously established HDM-induced allergic inflammation, by intratracheal administration of DUOX1-targeted siRNA or pharmacological NADPH oxidase inhibitors, reversed most of these outcomes. Our findings indicate an important function for DUOX1 in allergic inflammation related to persistent EGFR activation and suggest that DUOX1 targeting may represent an attractive strategy in asthma management.

  20. Bile acids regulate intestinal cell proliferation by modulating EGFR and FXR signaling.

    Science.gov (United States)

    Dossa, Avafia Y; Escobar, Oswaldo; Golden, Jamie; Frey, Mark R; Ford, Henri R; Gayer, Christopher P

    2016-01-15

    Bile acids (BAs) are synthesized in the liver and secreted into the intestine. In the lumen, enteric bacteria metabolize BAs from conjugated, primary forms into more toxic unconjugated, secondary metabolites. Secondary BAs can be injurious to the intestine and may contribute to disease. The epidermal growth factor receptor (EGFR) and the nuclear farnesoid X receptor (FXR) are known to interact with BAs. In this study we examined the effects of BAs on intestinal epithelial cell proliferation and investigated the possible roles for EGFR and FXR in these effects. We report that taurine-conjugated cholic acid (TCA) induced proliferation, while its unconjugated secondary counterpart deoxycholic acid (DCA) inhibited proliferation. TCA stimulated phosphorylation of Src, EGFR, and ERK 1/2. Pharmacological blockade of any of these pathways or genetic ablation of EGFR abrogated TCA-stimulated proliferation. Interestingly, Src or EGFR inhibitors eliminated TCA-induced phosphorylation of both molecules, suggesting that their activation is interdependent. In contrast to TCA, DCA exposure diminished EGFR phosphorylation, and pharmacological or siRNA blockade of FXR abolished DCA-induced inhibition of proliferation. Taken together, these results suggest that TCA induces intestinal cell proliferation via Src, EGFR, and ERK activation. In contrast, DCA inhibits proliferation via an FXR-dependent mechanism that may include downstream inactivation of the EGFR/Src/ERK pathway. Since elevated secondary BA levels are the result of specific bacterial modification, this may provide a mechanism through which an altered microbiota contributes to normal or abnormal intestinal epithelial cell proliferation.

  1. CRIPTO1 expression in EGFR-mutant NSCLC elicits intrinsic EGFR-inhibitor resistance

    OpenAIRE

    Park, Kang-Seo; Raffeld, Mark; Moon, Yong Wha; Xi, Liqiang; Bianco, Caterina; Van Pham, Trung; Lee, Liam C.; Mitsudomi, Tetsuya; Yatabe, Yasushi; Okamoto, Isamu; Subramaniam, Deepa; Mok, Tony; Rosell, Rafael; Luo, Ji; Salomon, David S.

    2014-01-01

    The majority of non–small cell lung cancer (NSCLC) patients harbor EGFR-activating mutations that can be therapeutically targeted by EGFR tyrosine kinase inhibitors (EGFR-TKI), such as erlotinib and gefitinib. Unfortunately, a subset of patients with EGFR mutations are refractory to EGFR-TKIs. Resistance to EGFR inhibitors reportedly involves SRC activation and induction of epithelial-to-mesenchymal transition (EMT). Here, we have demonstrated that overexpression of CRIPTO1, an EGF-CFC protei...

  2. Analgesic and Anti-Inflammatory Properties of Gelsolin in Acetic Acid Induced Writhing, Tail Immersion and Carrageenan Induced Paw Edema in Mice.

    Directory of Open Access Journals (Sweden)

    Ashok Kumar Gupta

    Full Text Available Plasma gelsolin levels significantly decline in several disease conditions, since gelsolin gets scavenged when it depolymerizes and caps filamentous actin released in the circulation following tissue injury. It is well established that our body require/implement inflammatory and analgesic responses to protect against cell damage and injury to the tissue. This study was envisaged to examine analgesic and anti-inflammatory activity of exogenous gelsolin (8 mg/mouse in mice models of pain and acute inflammation. Administration of gelsolin in acetic acid-induced writhing and tail immersion tests not only demonstrated a significant reduction in the number of acetic acid-induced writhing effects, but also exhibited an analgesic activity in tail immersion test in mice as compared to placebo treated mice. Additionally, anti-inflammatory function of gelsolin (8 mg/mouse compared with anti-inflammatory drug diclofenac sodium (10 mg/kg] was confirmed in the carrageenan injection induced paw edema where latter was measured by vernier caliper and fluorescent tomography imaging. Interestingly, results showed that plasma gelsolin was capable of reducing severity of inflammation in mice comparable to diclofenac sodium. Analysis of cytokines and histopathological examinations of tissue revealed administration of gelsolin and diclofenac sodium significantly reduced production of pro-inflammatory cytokines, TNF-α and IL-6. Additionally, carrageenan groups pretreated with diclofenac sodium or gelsolin showed a marked decrease in edema and infiltration of inflammatory cells in paw tissue. Our study provides evidence that administration of gelsolin can effectively reduce the pain and inflammation in mice model.

  3. Analgesic and Anti-Inflammatory Properties of Gelsolin in Acetic Acid Induced Writhing, Tail Immersion and Carrageenan Induced Paw Edema in Mice

    Science.gov (United States)

    Gupta, Ashok Kumar; Parasar, Devraj; Sagar, Amin; Choudhary, Vikas; Chopra, Bhupinder Singh; Garg, Renu; Ashish; Khatri, Neeraj

    2015-01-01

    Plasma gelsolin levels significantly decline in several disease conditions, since gelsolin gets scavenged when it depolymerizes and caps filamentous actin released in the circulation following tissue injury. It is well established that our body require/implement inflammatory and analgesic responses to protect against cell damage and injury to the tissue. This study was envisaged to examine analgesic and anti-inflammatory activity of exogenous gelsolin (8 mg/mouse) in mice models of pain and acute inflammation. Administration of gelsolin in acetic acid-induced writhing and tail immersion tests not only demonstrated a significant reduction in the number of acetic acid-induced writhing effects, but also exhibited an analgesic activity in tail immersion test in mice as compared to placebo treated mice. Additionally, anti-inflammatory function of gelsolin (8 mg/mouse) compared with anti-inflammatory drug diclofenac sodium (10 mg/kg)] was confirmed in the carrageenan injection induced paw edema where latter was measured by vernier caliper and fluorescent tomography imaging. Interestingly, results showed that plasma gelsolin was capable of reducing severity of inflammation in mice comparable to diclofenac sodium. Analysis of cytokines and histo-pathological examinations of tissue revealed administration of gelsolin and diclofenac sodium significantly reduced production of pro-inflammatory cytokines, TNF-α and IL-6. Additionally, carrageenan groups pretreated with diclofenac sodium or gelsolin showed a marked decrease in edema and infiltration of inflammatory cells in paw tissue. Our study provides evidence that administration of gelsolin can effectively reduce the pain and inflammation in mice model. PMID:26426535

  4. Molecular Mechanism of Differentiation and Apoptosis of U937 Cells Induced by 12-O-Tetradecanoylphorbol-13-Acetate

    Institute of Scientific and Technical Information of China (English)

    Ying Luo; Yunpeng Liu; Kezuo Hou; Su Wang; Yan Wang

    2005-01-01

    OBJECTIVE To explore the effects of 12-O-tetradecanoylphorbol-13-acetate (TPA) on differentiation, apoptosis and related molecular mechanisms in U937 myelomonocytic leukemia cells.METHODS Morphological changes were analyzed by phase contrast and light microscopy, expression of the monocytic differentiation maker CD11b by direct immunofluorescence staining, cell cycle distribution and apoptosis by flow cytometry, and expression of bcl-2, Bax, survivin and p21Cip1/Waf1proteins by Western analysis.RESULTS Treatment of U937 cells with 10 nmol/L TPA induced cell adherence. The adherent cells showed G0/G1 cell cycle arrest (69.0% at 24h vs 52.1% control; P< 0.01),and morphologic changes and increased expression of the monocytic differentiation marker CD11b (63.0% at 72 h vs15.3% control; P< 0.01 ). In addition to these effects, about 20% of the cells still remained in suspension and exhibited a time-dependent increasing apoptosis, which reached 70.3% after 72 h of treatment ( P< 0.01 ). TPA treatment for 24 h induced expression of p21Cip1/Waf1 in the adherent cells, but not in the non-adherent cells. Furthermore, bcl-2 and survivin expression declined in 24 h-TPA-treated non-adherent cells compared with untreated control and adherent cells, whereas no change in the expression of Bax was detected.CONCLUSION TPA induces both differentiation and apoptosis in U937 cells,which may be related to the upregulation of p21Cip1/Waf1 and downregulation of bcl-2 and survivin expression.

  5. Bioactive peptide carnosin protects against lead acetate-induced hepatotoxicity by abrogation of oxidative stress in rats.

    Science.gov (United States)

    Hasanein, Parisa; Kazemian-Mahtaj, Azam; Khodadadi, Iraj

    2016-08-01

    Context Oxidative stress is a common mechanism of liver injury. Carnosine is a dipeptide having strong antioxidant effects. Objectives We investigated the effects of carnosine on lead-induced hepatotoxicity and oxidative stress in rats. Materials and methods Animals received an aqueous solution of lead acetate (500 mg Pb/L in the drinking water) and/or daily oral gavage of carnosine (10 mg/kg) for 8 weeks. Rats were then weighed and used for the biochemical (commercial kits), molecular (standard chemical methods) and histological (microscopic) evaluations. Results Lead-induced oxidative stress in liver tissue was indicated by a significant increase in the level of malondialdehyde (MDA) (8.25 ± 0.15 nmol/mg) as well as decrease in the level of total antioxidant capacity (TAC) (1.72 ± 0.25 μmol/g) and total thiol (SH) groups) 1.9 ± 0.22 μmol/g). Carnosine treatment decreased MDA (4 ± 0.08 nmol/mg), whereas it increased the contents of total thiol (3.25 ± 0.04 μmol/g) and TAC (3.44 ± 0.32 μmol/g) in the lead group. Carnosine also prevented the decreased body weight (p carnosine attenuates liver damage by decreasing necrosis and infiltration of inflammatory cells. Conclusion Carnosine prevented lead-induced hepatotoxicity, indicated by molecular, biochemical and histopathological analyses through inhibiting lipid peroxidation and enhancing antioxidant defence systems. Therefore, carnosine makes a good candidate to protect against the deleterious effect of chronic lead intoxication. PMID:26808926

  6. Harpagophytum Procumbens Ethyl Acetate Fraction Reduces Fluphenazine-Induced Vacuous Chewing Movements and Oxidative Stress in Rat Brain.

    Science.gov (United States)

    Schaffer, Larissa Finger; de Freitas, Catiuscia Molz; Chiapinotto Ceretta, Ana Paula; Peroza, Luis Ricardo; de Moraes Reis, Elizete; Krum, Bárbara Nunes; Busanello, Alcindo; Boligon, Aline Augusti; Sudati, Jéssie Haigert; Fachinetto, Roselei; Wagner, Caroline

    2016-05-01

    Long-term treatment with fluphenazine is associated with manifestation of extrapyramidal side effects, such as tardive dyskinesia. The molecular mechanisms related to the pathophysiology of TD remain unclear, and several hypotheses, including a role for oxidative stress, have been proposed. Harpagophytum procumbens is an herbal medicine used mainly due to anti-inflammatory effects, but it also exhibits antioxidant effects. We investigated the effect of ethyl acetate fraction of H. procumbens (EAF HP) in fluphenazine-induced orofacial dyskinesia by evaluating behavioral parameters at different times (vacuous chewing movements (VCM's) and locomotor and exploratory activity), biochemical serological analyses, and biochemical markers of oxidative stress of the liver, kidney, cortex, and striatum. Chronic administration of fluphenazine (25 mg/kg, intramuscular (i.m) significantly increased the VCMs at all analyzed times (2, 7, 14, and 21 days), and this was inhibited by EAF HP (especially at a dose of 30 mg/kg). Fluphenazine decreased locomotion and exploratory activity, and EAF HP did not improve this decrease. Fluphenazine induced oxidative damage, as identified by changes in catalase activity and ROS levels in the cortex and striatum, which was reduced by EAF HP, especially in the striatum. In the cortex, EAF HP was protective against fluphenazine-induced changes in catalase activity but not against the increase in ROS level. Furthermore, EAF HP was shown to be safe, since affected serum biochemical parameters or parameters of oxidative stress in the liver and kidney. These findings suggest that the H. procumbens is a promising therapeutic agent for the treatment of involuntary oral movements.

  7. Harpagophytum Procumbens Ethyl Acetate Fraction Reduces Fluphenazine-Induced Vacuous Chewing Movements and Oxidative Stress in Rat Brain.

    Science.gov (United States)

    Schaffer, Larissa Finger; de Freitas, Catiuscia Molz; Chiapinotto Ceretta, Ana Paula; Peroza, Luis Ricardo; de Moraes Reis, Elizete; Krum, Bárbara Nunes; Busanello, Alcindo; Boligon, Aline Augusti; Sudati, Jéssie Haigert; Fachinetto, Roselei; Wagner, Caroline

    2016-05-01

    Long-term treatment with fluphenazine is associated with manifestation of extrapyramidal side effects, such as tardive dyskinesia. The molecular mechanisms related to the pathophysiology of TD remain unclear, and several hypotheses, including a role for oxidative stress, have been proposed. Harpagophytum procumbens is an herbal medicine used mainly due to anti-inflammatory effects, but it also exhibits antioxidant effects. We investigated the effect of ethyl acetate fraction of H. procumbens (EAF HP) in fluphenazine-induced orofacial dyskinesia by evaluating behavioral parameters at different times (vacuous chewing movements (VCM's) and locomotor and exploratory activity), biochemical serological analyses, and biochemical markers of oxidative stress of the liver, kidney, cortex, and striatum. Chronic administration of fluphenazine (25 mg/kg, intramuscular (i.m) significantly increased the VCMs at all analyzed times (2, 7, 14, and 21 days), and this was inhibited by EAF HP (especially at a dose of 30 mg/kg). Fluphenazine decreased locomotion and exploratory activity, and EAF HP did not improve this decrease. Fluphenazine induced oxidative damage, as identified by changes in catalase activity and ROS levels in the cortex and striatum, which was reduced by EAF HP, especially in the striatum. In the cortex, EAF HP was protective against fluphenazine-induced changes in catalase activity but not against the increase in ROS level. Furthermore, EAF HP was shown to be safe, since affected serum biochemical parameters or parameters of oxidative stress in the liver and kidney. These findings suggest that the H. procumbens is a promising therapeutic agent for the treatment of involuntary oral movements. PMID:26732278

  8. A view on EGFR-targeted therapies from the oncogene-addiction perspective

    Directory of Open Access Journals (Sweden)

    Rolando ePerez

    2013-04-01

    Full Text Available Tumor cell growth and survival can often be impaired by inactivating a single oncogen – a phenomenon that has been called as 'oncogene addiction'. It is in such scenarios that molecular targeted therapies may succeed. Among known oncogenes, the epidermal growth factor receptor (EGFR has become the target of different cancer therapies. So far, however, the clinical benefit from EGFR-targeted therapies has been rather limited. A critical review of the large amount of clinical data obtained with anti-EGFR agents, carried out from the perspective of the oncogene addiction concept, may help to understand the causes of the unsatisfactory results. In this article we intend to do such an exercise taking as basis for the analysis a few case studies of anti-EGFR agents that are currently in the clinic. There, the 'EGFR addiction' phenomenon becomes apparent in high-responder patients. We further discuss how the concept of oncogene addiction needs to be interpreted on the light of emerging experimental evidences and ideas; in particular, that EGFR addiction may reflect the interconnection of several cellular pathways. In this regard we set forth several hypotheses; namely, that requirement of higher glucose uptake by hypoxic tumor cells may reinforce EGFR addiction; and that chronic use of EGFR-targeted antibodies in EGFR-addicted tumors would induce stable disease by reversing the malignant phenotype of cancer stem cells and also by sustaining an anti-tumor T cell response. Finally, we discuss possible reasons for the failure of certain combinatorial therapies involving anti-EGFR agents, arguing that some of these agents might produce either a negative or a positive trans-modulation effect on other oncogenes. It becomes evident that we need operational definitions of EGFR addiction in order to determine which patient populations may benefit from treatment with anti-EGFR drugs, and to improve the design of these therapies.

  9. Protein Kinase G facilitates EGFR-mediated cell death in MDA-MB-468 cells.

    Science.gov (United States)

    Jackson, Nicole M; Ceresa, Brian P

    2016-08-15

    The Epidermal Growth Factor Receptor (EGFR) is a transmembrane receptor tyrosine kinase with critical implications in cell proliferation, migration, wound healing and the regulation of apoptosis. However, the EGFR has been shown to be hyper-expressed in a number of human malignancies. The MDA-MB-468 metastatic breast cell line is one example of this. This particular cell line hyper-expresses the EGFR and undergoes EGFR-mediated apoptosis in response to EGF ligand. The goal of this study was to identify the kinases that could be potential intermediates for the EGFR-mediated induction of apoptosis intracellularly. After identifying Cyclic GMP-dependent Protein Kinase G (PKG) as a plausible intermediate, we wanted to determine the temporal relationship of these two proteins in the induction of apoptosis. We observed a dose-dependent decrease in MDA-MB-468 cell viability, which was co-incident with increased PKG activity as measured by VASPSer239 phosphorylation. In addition, we observed a dose dependent decrease in cell viability, as well as an increase in apoptosis, in response to two different PKG agonists, 8-Bromo-cGMP and 8-pCPT-cGMP. MDA-MB-468 cells with reduced PKG activity had attenuated EGFR-mediated apoptosis. These findings indicate that PKG does not induce cell death via transphosphorylation of the EGFR. Instead, PKG activity occurs following EGFR activation. Together, these data indicate PKG as an intermediary in EGFR-mediated cell death, likely via apoptotic pathway. PMID:27381222

  10. Alpha1a-Adrenoceptor Genetic Variant Triggers Vascular Smooth Muscle Cell Hyperproliferation and Agonist Induced Hypertrophy via EGFR Transactivation Pathway.

    Directory of Open Access Journals (Sweden)

    Irina Gradinaru

    Full Text Available α1a Adrenergic receptors (α1aARs are the predominant AR subtype in human vascular smooth muscle cells (SMCs. α1aARs in resistance vessels are crucial in the control of blood pressure, yet the impact of naturally occurring human α1aAR genetic variants in cardiovascular disorders remains poorly understood. To this end, we present novel findings demonstrating that 3D cultures of vascular SMCs expressing human α1aAR-247R (247R genetic variant demonstrate significantly increased SMC contractility compared with cells expressing the α1aAR-WT (WT receptor. Stable expression of 247R genetic variant also triggers MMP/EGFR-transactivation dependent serum- and agonist-independent (constitutive hyperproliferation and agonist-dependent hypertrophy of SMCs. Agonist stimulation reduces contractility Using pathway-specific inhibitors we determined that the observed hyperproliferation of 247R-expressing cells is triggered via β-arrestin1/Src/MMP-2/EGFR/ERK-dependent mechanism. MMP-2-specific siRNA inhibited 247R-triggered hyperproliferation indicating MMP-2 involvement in 247R-triggered hyperproliferation in SMCs. β-arrestin1-specific shRNA also inhibited 247R-triggered hyperproliferation but did not affect hypertrophy in 247R-expressing SMCs, indicating that agonist-dependent hypertrophy is independent of β-arrestin1. Our data reveal that in different cardiovascular cells the same human receptor genetic variant can activate alternative modulators of the same signaling pathway. Thus, our findings in SMCs demonstrate that depending on the type of cells expressing the same receptor (or receptor variant, different target-specific inhibitors could be used to modulate aberrant hyperproliferative or hypertrophic pathways in order to restore normal phenotype.

  11. Insulin and phorbol myristic acetate induce ornithine decarboxylase in Reuber H35 rat hepatoma cells by different mechanisms.

    Science.gov (United States)

    Goodman, S A; Esau, B; Koontz, J W

    1988-11-01

    Reuber H35 rat hepatoma cells respond to insulin or to tumor promoting phorbol esters with an increase in ornithine decarboxylase enzyme activity. This occurs in a time- and dose-dependent manner with both types of agonist. We report here that the increase in ornithine decarboxylase activity with optimal concentrations of both agonists is additive. Furthermore, the initial increase is dependent on continued RNA and protein synthesis. We also find that both of these agonists cause an increase in mRNA coding for ornithine decarboxylase in a time- and dose-dependent manner which suggests that the increase in enzyme activity can be accounted for by the increase in transcript levels. The difference in the time course of induction by the agonists, the additivity of induction by the two agonists, the differential sensitivity of induction to cycloheximide and RNA synthesis inhibitors, and the observation that phorbol myristic acetate causes a further increase in ornithine decarboxylase activity and transcript levels in cells already maximally induced by insulin suggest that these two agonists act through separate mechanisms.

  12. Healing Effect of PistaciaAtlantica Fruit Oil Extract in Acetic Acid-Induced Colitis in Rats

    Directory of Open Access Journals (Sweden)

    Nader Tanideh

    2014-11-01

    Full Text Available Background: Considering the anti-oxidant properties of Pistaciaatlanticaand lack of data regarding its efficacy in the treatment of ulcerative colitis, this study aims at investigating the effect of the Pistaciaatlantica fruit extract in treating experimentally induced colitis in a rat model. Methods:Seventy male Sprague-Dawley rats (weighing 220±20 g were used. All rats fasted 24 hours before the experimental procedure. The rats were randomly divided into 7 groups, each containing 10 induced colitis with 2ml acetic acid (3%. Group 1 (Asacol, group 2 (base gel and group 7 (without treatment were assigned as control groups. Group 3 (300 mg/ml and group 4 (600 mg/ml received Pistaciaatlantica fruit orally. Group 5 (10% gel and group 6 (20% gel received Pistaciaatlantica in the form of gel as enema. Macroscopic, histopathological examination and MDA measurement were carried out. Results:All groups revealed significant macroscopic healing in comparison with group 7 (P<0.001. Regarding microscopic findings in the treatment groups compared with group 7, the latter group differed significantly with groups 1, 2, 4 and 6 (P<0.001. There was a significant statistical difference in MDA scores of the seven treatment groups (F(5,54=76.61, P<0.001. Post-hoc comparisons indicated that the mean±SD score of Asacol treated group (1.57±0.045 was not significantly different from groups 4 (1.62±0.024 and 6 (1.58±0.028. Conclusion: Our study showed that a high dose of Pistaciaatlantica fruit oil extract, administered orally and rectally can improve colitis physiologically and pathologically in a rat model, and may be efficient for ulcerative colitis.

  13. Leptin modulates human Sertoli cells acetate production and glycolytic profile: a novel mechanism of obesity-induced male infertility?

    Science.gov (United States)

    Martins, Ana D; Moreira, Ana C; Sá, Rosália; Monteiro, Mariana P; Sousa, Mário; Carvalho, Rui A; Silva, Branca M; Oliveira, Pedro F; Alves, Marco G

    2015-09-01

    Human feeding behavior and lifestyle are gradually being altered, favoring the development of metabolic diseases, particularly type 2 diabetes and obesity. Leptin is produced by the adipose tissue acting as a satiety signal. Its levels have been positively correlated with fat mass and hyperleptinemia has been proposed to negatively affect male reproductive function. Nevertheless, the molecular mechanisms by which this hormone affects male fertility remain unknown. Herein, we hypothesize that leptin acts on human Sertoli cells (hSCs), the "nurse cells" of spermatogenesis, altering their metabolism. To test our hypothesis, hSCs were cultured without or with leptin (5, 25 and 50ng/mL). Leptin receptor was identified by qPCR and Western blot. Protein levels of glucose transporters (GLUT1, GLUT2 and GLUT3), phosphofructokinase, lactate dehydrogenase (LDH) and monocarboxylate transporter 4 (MCT4) were determined by Western Blot. LDH activity was assessed and metabolite production/consumption determined by proton nuclear magnetic resonance. Oxidative damage was evaluated by assessing lipid peroxidation, protein carbonilation and nitration. Our data shows that leptin receptor is expressed in hSCs. The concentration of leptin found in lean, healthy patients, upregulated GLUT2 protein levels and concentrations of leptin found in lean and obese patients increased LDH activity. Of note, all leptin concentrations decreased hSCs acetate production illustrating a novel mechanism for this hormone action. Moreover, our data shows that leptin does not induce or protect hSCs from oxidative damage. We report that this hormone modulates the nutritional support of spermatogenesis, illustrating a novel mechanism that may be linked to obesity-induced male infertility. PMID:26071642

  14. Phorbol 12-myristate 13-acetate induces protein kinase ceta-specific proliferative response in astrocytic tumor cells.

    Science.gov (United States)

    Hussaini, I M; Karns, L R; Vinton, G; Carpenter, J E; Redpath, G T; Sando, J J; VandenBerg, S R

    2000-07-21

    Protein kinase C (PKC) activation has been implicated in cellular proliferation in neoplastic astrocytes. The roles for specific PKC isozymes in regulating this glial response, however, are not well understood. The aim of this study was to characterize the expression of PKC isozymes and the role of PKC-eta expression in regulating cellular proliferation in two well characterized astrocytic tumor cell lines (U-1242 MG and U-251 MG) with different properties of growth in cell culture. Both cell lines expressed an array of conventional (alpha, betaI, betaII, and gamma) and novel (theta and epsilon) PKC isozymes that can be activated by phorbol myristate acetate (PMA). Another novel PKC isozyme, PKC-eta, was only expressed by U-251 MG cells. In contrast, PKC-delta was readily detected in U-1242 MG cells but was present only at low levels in U-251 MG cells. PMA (100 nm) treatment for 24 h increased cell proliferation by over 2-fold in the U-251 MG cells, whereas it decreased the mitogenic response in the U-1242 MG cells by over 90%. When PKC-eta was stably transfected into U-1242 MG cells, PMA increased cell proliferation by 2.2-fold, similar to the response of U-251 MG cells. The cell proliferation induced by PMA in both the U-251 MG and U-1242-PKC-eta cells was blocked by the PKC inhibitor bisindolylmaleimide (0.5 micrometer) and the MEK inhibitor, PD 98059 (50 micrometer). Transient transfection of wild type U-251 with PKC-eta antisense oligonucleotide (1 micrometer) also blocked the PMA-induced increase in [(3)H]thymidine incorporation. The data demonstrate that two glioblastoma lines, with functionally distinct proliferative responses to PMA, express different novel PKC isozymes and that the differential expression of PKC-eta plays a determining role in the different proliferative capacity. PMID:10806212

  15. Ethyl Acetate Extract of Origanum vulgare L. ssp. hirtum Prevents Streptozotocin-Induced Diabetes in C57BL/6 Mice.

    Science.gov (United States)

    Vujicic, Milica; Nikolic, Ivana; Kontogianni, Vassiliki G; Saksida, Tamara; Charisiadis, Pantelis; Vasic, Bobana; Stosic-Grujicic, Stanislava; Gerothanassis, Ioannis P; Tzakos, Andreas G; Stojanovic, Ivana

    2016-07-01

    Type 1 diabetes (T1D) is an autoimmune disease that develops as a consequence of pancreatic β-cell death induced by proinflammatory mediators. Because Origanum vulgare L. ssp. hirtum (Greek oregano) contains antiinflammatory molecules, we hypothesized that it might be beneficial for the treatment of T1D. An ethyl acetate extract of oregano (EAO) was prepared from the leaves by a polar extraction method. Phytochemical composition was determined by liquid chromatography-UV diode array coupled to ion-trap mass spectrometry with electrospray ionization interface (LC/DAD/ESI-MS(n) ). In vitro immunomodulatory effect of EAO was estimated by measuring proliferation (MTT) or cytokine secretion (ELISA) from immune cells. Diabetes was induced by multiple low doses of streptozotocin (MLDS) in male C57BL/6 mice and EAO was administered intraperitoneally for 10 d. Determination of cellular composition (flow cytometry) and cytokine production (ELISA) was performed on 12th d after diabetes induction. EAO suppressed the function of both macrophages and lymphocytes in vitro. In vivo, EAO treatment significantly preserved pancreatic islets and reduced diabetes incidence in MLDS-challenged mice. Besides down-modulatory effect on macrophages, EAO reduced the number of total CD4(+) and activated CD4(+) CD25(+) T cells. Furthermore, EAO affected the number of T helper 1 (Th1) and T helper 17 (Th17) cells through downregulation of their key transcription factors T-bet and RORγT. Because EAO treatment protects mice from development of hyperglycemia by reducing proinflammatory macrophage/Th1/Th17 response, this plant extract could represent a basis for future diabetes therapy. PMID:27219840

  16. An in vivo C. elegans model system for screening EGFR-inhibiting anti-cancer drugs.

    Directory of Open Access Journals (Sweden)

    Young-Ki Bae

    Full Text Available The epidermal growth factor receptor (EGFR is a well-established target for cancer treatment. EGFR tyrosine kinase (TK inhibitors, such as gefinitib and erlotinib, have been developed as anti-cancer drugs. Although non-small cell lung carcinoma with an activating EGFR mutation, L858R, responds well to gefinitib and erlotinib, tumors with a doubly mutated EGFR, T790M-L858R, acquire resistance to these drugs. The C. elegans EGFR homolog LET-23 and its downstream signaling pathway have been studied extensively to provide insight into regulatory mechanisms conserved from C. elegans to humans. To develop an in vivo screening system for potential cancer drugs targeting specific EGFR mutants, we expressed three LET-23 chimeras in which the TK domain was replaced with either the human wild-type TK domain (LET-23::hEGFR-TK, a TK domain with the L858R mutation (LET-23::hEGFR-TK[L858R], or a TK domain with the T790M-L858R mutations (LET-23::hEGFR-TK[T790M-L858R] in C. elegans vulval cells using the let-23 promoter. The wild-type hEGFR-TK chimeric protein rescued the let-23 mutant phenotype, and the activating mutant hEGFR-TK chimeras induced a multivulva (Muv phenotype in a wild-type C. elegans background. The anti-cancer drugs gefitinib and erlotinib suppressed the Muv phenotype in LET-23::hEGFR-TK[L858R]-expressing transgenic animals, but not in LET-23::hEGFR-TK[T790M-L858R] transgenic animals. As a pilot screen, 8,960 small chemicals were tested for Muv suppression, and AG1478 (an EGFR-TK inhibitor and U0126 (a MEK inhibitor were identified as potential inhibitors of EGFR-mediated biological function. In conclusion, transgenic C. elegans expressing chimeric LET-23::hEGFR-TK proteins are a model system that can be used in mutation-specific screens for new anti-cancer drugs.

  17. The Effect of Kinetin, Gibberellic Acid and Indole Acetic Acid on EMS-Induced Somatic Mutation and Recombination in Drosophila melanogaster

    OpenAIRE

    YEŞİLADA, Elif

    2000-01-01

    The effect of plant growth hormones (kinetin, gibberellic acid (GA 3) and indole acetic acid (IAA)) on EMS-induced mutant wing spots was studied with the somatic mutation and recombination test (SMART) in Drosophila melanogaster.GA 3 reduced all kinds of EMS-induced spot. While a 10 -3 M concentration of kinetin reduced only the number of EMS-induced twin spots, a 10 -4 M concentration was seen to increase the number of all types of spot. The same concentrations of IAA gave variable resu...

  18. EGFR Regulates the Development and Microarchitecture of Intratumoral Angiogenic Vasculature Capable of Sustaining Cancer Cell Intravasation

    Directory of Open Access Journals (Sweden)

    Petra Minder

    2015-08-01

    Full Text Available Many malignant characteristics of cancer cells are regulated through pathways induced by the tyrosine kinase activity of the epidermal growth factor receptor (EGFR. Herein, we show that besides directly affecting the biology of cancer cells per se, EGFR also regulates the primary tumor microenvironment. Specifically, our findings demonstrate that both the expression and signaling activity of EGFR are required for the induction of a distinct intratumoral vasculature capable of sustaining tumor cell intravasation, a critical rate-limiting step in the metastatic cascade. An intravasation-sustaining mode of intratumoral angiogenic vessels depends on high levels of tumor cell EGFR and the interplay between EGFR-regulated production of interleukin 8 by tumor cells, interleukin-8–induced influx of tumor-infiltrating neutrophils delivering their unique matrix metalloproteinase-9, and neutrophil matrix metalloproteinase-9–dependent release of the vascular permeability and endothelial growth factor, VEGF. Our data indicate that through VEGF-mediated disruption of endothelial layer integrity and increase of intratumoral vasculature permeability, EGFR activity significantly facilitates active intravasation of cancer cells. Therefore, this study unraveled an important but overlooked function of EGFR in cancer, namely, its ability to create an intravasation-sustaining microenvironment within the developing primary tumor by orchestrating several interrelated processes required for the initial steps of cancer metastasis through vascular routes. Our findings also suggest that EGFR-targeted therapies might be more effective when implemented in cancer patients with early-staged primary tumors containing a VEGF-dependent angiogenic vasculature. Accordingly, early EGFR inhibition combined with various anti-VEGF approaches could synergistically suppress tumor cell intravasation through inhibiting the highly permeable angiogenic vasculature induced by EGFR

  19. Mitochondrial proteomics of the acetic acid – induced programmed cell death response in a highly tolerant Zygosaccharomyces bailii – derived hybrid strain

    Directory of Open Access Journals (Sweden)

    Joana F Guerreiro

    2016-01-01

    Full Text Available Very high concentrations of acetic acid at low pH induce programmed cell death (PCD in both the experimental model Saccharomyces cerevisiae and in Zygosaccharomyces bailii, the latter being considered the most problematic acidic food spoilage yeast due to its remarkable intrinsic resistance to this food preservative. However, while the mechanisms underlying S. cerevisiae PCD induced by acetic acid have been previously examined, the corresponding molecular players remain largely unknown in Z. bailii. Also, the reason why acetic acid concentrations known to be necrotic for S. cerevisiae induce PCD with an apoptotic phenotype in Z. bailii remains to be elucidated. In this study, a 2-DE-based expression mitochondrial proteomic analysis was explored to obtain new insights into the mechanisms involved in PCD in the Z. bailii derived hybrid strain ISA1307. This allowed the quantitative assessment of expression of protein species derived from each of the parental strains, with special emphasis on the processes taking place in the mitochondria known to play a key role in acetic acid – induced PCD. A marked decrease in the content of proteins involved in mitochondrial metabolism, in particular, in respiratory metabolism (Cor1, Rip1, Lpd1, Lat1 and Pdb1, with a concomitant increase in the abundance of proteins involved in fermentation (Pdc1, Ald4, Dld3 was registered. Other differentially expressed identified proteins also suggest the involvement of the oxidative stress response, protein translation, amino acid and nucleotide metabolism, among other processes, in the PCD response. Overall, the results strengthen the emerging concept of the importance of metabolic regulation of yeast PCD.

  20. The Antitumorigenic Function of EGFR in Metastatic Breast Cancer is Regulated by Expression of Mig6

    Directory of Open Access Journals (Sweden)

    Michael K. Wendt

    2015-01-01

    Full Text Available Numerous studies by our lab and others demonstrate that epidermal growth factor receptor (EGFR plays critical roles in primary breast cancer (BC initiation, growth and dissemination. However, clinical trials targeting EGFR function in BC have lead to disappointing results. In the current study we sought to identify the mechanisms responsible for this disparity by investigating the function of EGFR across the continuum of the metastatic cascade. We previously established that overexpression of EGFR is sufficient for formation of in situ primary tumors by otherwise nontransformed murine mammary gland cells. Induction of epithelial-mesenchymal transition (EMT is sufficient to drive the metastasis of these EGFR-transformed tumors. Examining growth factor receptor expression across this and other models revealed a potent downregulation of EGFR through metastatic progression. Consistent with diminution of EGFR following EMT and metastasis EGF stimulation changes from a proliferative to an apoptotic response in in situ versus metastatic tumor cells, respectively. Furthermore, overexpression of EGFR in metastatic MDA-MB-231 BC cells promoted their antitumorigenic response to EGF in three dimensional (3D metastatic outgrowth assays. In line with the paradoxical function of EGFR through EMT and metastasis we demonstrate that the EGFR inhibitory molecule, Mitogen Induced Gene-6 (Mig6, is tumor suppressive in in situ tumor cells. However, Mig6 expression is absolutely required for prevention of apoptosis and ultimate metastasis of MDA-MB-231 cells. Further understanding of the paradoxical function of EGFR between primary and metastatic tumors will be essential for application of its targeted molecular therapies in BC.

  1. Correlation between EGFR gene mutation, cytologic tumor markers, 18F-FDG uptake in non-small cell lung cancer

    OpenAIRE

    Cho, Arthur; Hur, Jin; Moon, Yong Wha; Hong, Sae Rom; Suh, Young Joo; Kim, Yun Jung; Im, Dong Jin; Hong, Yoo Jin; Lee, Hye-Jeong; Kim, Young Jin; Shim, Hyo Sup; Lee, Jae Seok; Kim, Joo-Hang; Choi, Byoung Wook

    2016-01-01

    Background EGFR mutation-induced cell proliferation causes changes in tumor biology and tumor metabolism, which may reflect tumor marker concentration and 18F-FDG uptake on PET/CT. Direct aspirates of primary lung tumors contain different concentrations of tumor markers than serum tumor markers, and may correlate better with EGFR mutation than serum tumor markers. The purpose of this study is to investigate an association between cytologic tumor markers and FDG uptake with EGFR mutation statu...

  2. Effect of deoxycorticosterone acetate-salt-induced hypertension on diabetic peripheral neuropathy in alloxan-induced diabetic WBN/Kob rats.

    Science.gov (United States)

    Ozaki, Kiyokazu; Hamano, Hiroko; Matsuura, Tetsuro; Narama, Isao

    2016-01-01

    The relationship between hypertension and diabetic peripheral neuropathy (DPN) has recently been reported in clinical research, but it remains unclear whether hypertension is a risk factor for DPN. To investigate the effects of hypertension on DPN, we analyzed morphological features of peripheral nerves in diabetic rats with hypertension. Male WBN/Kob rats were divided into 2 groups: alloxan-induced diabetic rats with deoxycorticosterone acetate-salt (DOCA-salt) treatment (ADN group) and nondiabetic rats with DOCA-salt treatment (DN group). Sciatic, tibial (motor) and sural (sensory) nerves were subjected to qualitative and quantitative histomorphological analysis. Systolic blood pressure in the two groups exhibited a higher value (>140 mmHg), but there was no significant difference between the two groups. Endoneurial blood vessels in both groups presented endothelial hypertrophy and narrowing of the vascular lumen. Electron microscopically, duplication of basal lamina surrounding the endothelium and pericyte of the endoneurial vessels was observed, and this lesion appeared to be more frequent and severe in the ADN group than the DN group. Many nerve fibers of the ADN and DN groups showed an almost normal appearance, whereas morphometrical analysis of the tibial nerve showed a significant shift to smaller fiber and myelin sizes in the ADN group compared with DN group. In sural nerve, the fiber and axon-size significantly shifted to a smaller size in ADN group compared with the DN group. These results suggest that combined diabetes and hypertension could induce mild peripheral nerve lesions with vascular changes. PMID:26989296

  3. Effect of deoxycorticosterone acetate-salt-induced hypertension on diabetic peripheral neuropathy in alloxan-induced diabetic WBN/Kob rats.

    Science.gov (United States)

    Ozaki, Kiyokazu; Hamano, Hiroko; Matsuura, Tetsuro; Narama, Isao

    2016-01-01

    The relationship between hypertension and diabetic peripheral neuropathy (DPN) has recently been reported in clinical research, but it remains unclear whether hypertension is a risk factor for DPN. To investigate the effects of hypertension on DPN, we analyzed morphological features of peripheral nerves in diabetic rats with hypertension. Male WBN/Kob rats were divided into 2 groups: alloxan-induced diabetic rats with deoxycorticosterone acetate-salt (DOCA-salt) treatment (ADN group) and nondiabetic rats with DOCA-salt treatment (DN group). Sciatic, tibial (motor) and sural (sensory) nerves were subjected to qualitative and quantitative histomorphological analysis. Systolic blood pressure in the two groups exhibited a higher value (>140 mmHg), but there was no significant difference between the two groups. Endoneurial blood vessels in both groups presented endothelial hypertrophy and narrowing of the vascular lumen. Electron microscopically, duplication of basal lamina surrounding the endothelium and pericyte of the endoneurial vessels was observed, and this lesion appeared to be more frequent and severe in the ADN group than the DN group. Many nerve fibers of the ADN and DN groups showed an almost normal appearance, whereas morphometrical analysis of the tibial nerve showed a significant shift to smaller fiber and myelin sizes in the ADN group compared with DN group. In sural nerve, the fiber and axon-size significantly shifted to a smaller size in ADN group compared with the DN group. These results suggest that combined diabetes and hypertension could induce mild peripheral nerve lesions with vascular changes.

  4. NF-{kappa}B signaling is activated and confers resistance to apoptosis in three-dimensionally cultured EGFR-mutant lung adenocarcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Sakuma, Yuji, E-mail: ysakuma@gancen.asahi.yokohama.jp [Molecular Pathology and Genetics Division, Kanagawa Cancer Center Research Institute, Yokohama (Japan); Yamazaki, Yukiko; Nakamura, Yoshiyasu; Yoshihara, Mitsuyo; Matsukuma, Shoichi; Koizume, Shiro; Miyagi, Yohei [Molecular Pathology and Genetics Division, Kanagawa Cancer Center Research Institute, Yokohama (Japan)

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer EGFR-mutant cells in 3D culture resist EGFR inhibition compared with suspended cells. Black-Right-Pointing-Pointer Degradation of I{kappa}B and activation of NF-{kappa}B are observed in 3D-cultured cells. Black-Right-Pointing-Pointer Inhibiting NF-{kappa}B enhances the efficacy of the EGFR inhibitor in 3D-cultured cells. -- Abstract: Epidermal growth factor receptor (EGFR)-mutant lung adenocarcinoma cells in suspension undergo apoptosis to a greater extent than adherent cells in a monolayer when EGFR autophosphorylation is inhibited by EGFR tyrosine kinase inhibitors (TKIs). This suggests that cell adhesion to a culture dish may activate an anti-apoptotic signaling pathway other than the EGFR pathway. Since the microenvironment of cells cultured in a monolayer are substantially different to that of cells existing in three-dimension (3D) in vivo, we assessed whether two EGFR-mutant lung adenocarcinoma cell lines, HCC827 and H1975, were more resistant to EGFR TKI-induced apoptosis when cultured in a 3D extracellular matrix (ECM) as compared with in suspension. The ECM-adherent EGFR-mutant cells in 3D were significantly less sensitive to treatment with WZ4002, an EGFR TKI, than the suspended cells. Further, a marked degradation of I{kappa}B{alpha}, the inhibitor of nuclear factor (NF)-{kappa}B, was observed only in the 3D-cultured cells, leading to an increase in the activation of NF-{kappa}B. Moreover, the inhibition of NF-{kappa}B with pharmacological inhibitors enhanced EGFR TKI-induced apoptosis in 3D-cultured EGFR-mutant cells. These results suggest that inhibition of NF-{kappa}B signaling would render ECM-adherent EGFR-mutant lung adenocarcinoma cells in vivo more susceptible to EGFR TKI-induced cell death.

  5. Thrombin stimulates VSMC proliferation through an EGFR-dependent pathway: involvement of MMP-2.

    Science.gov (United States)

    Smiljanic, Katarina; Obradovic, Milan; Jovanovic, Aleksandra; Djordjevic, Jelena; Dobutovic, Branislava; Jevremovic, Danimir; Marche, Pierre; Isenovic, Esma R

    2014-11-01

    In this study, the role of epidermal growth factor receptor (EGFR), extracellular signal-regulated kinase (ERK1/2), heparin-binding EGF-like growth factor (HB-EGF), general metalloproteinases, matrix metalloproteinases-2 (MMP-2) in mediating the mitogenic action of thrombin in rat vascular smooth muscle cells (VSMC) was investigated. The incubation of rat VSMC with thrombin (1 U/ml) for 5 min resulted in significant (p EGFR phosphorylation by 8.5 ± 1.3-fold (p EGFR tyrosine kinase irreversible inhibitor, 10 µM PD169540 (PD), and 20 µM anti-HB-EGF antibody significantly reduced thrombin-stimulated EGFR and ERK1/2 phosphorylation by 81, 72 % and by 48 and 61 %, respectively. Furthermore, the same pretreatments with PD or anti-HB-EGF antibody reduced thrombin-induced VSMC proliferation by 44 and 45 %, respectively. In addition, 30-min pretreatments with 10 µM specific MMP-2 inhibitor significantly reduced thrombin-stimulated phosphorylation of both EGFR and ERK1/2 by 25 %. Moreover, the same pretreatment with MMP-2 inhibitor reduced thrombin-induced VSMC proliferation by 45 %. These results show that the thrombin-induced DNA synthesis correlates with the level of ERK1/2 activation rather than EGFR activation. These results further suggest that thrombin acts through EGFR and ERK 1/2 signaling pathways involving MMP-2 to upregulate proliferation of VSMC.

  6. Effects of eslicarbazepine acetate on acute and chronic latrunculin A-induced seizures and extracellular amino acid levels in the mouse hippocampus

    OpenAIRE

    Sierra-Paredes, Germán; Loureiro, Ana I; Wright, Lyndon C; Sierra-Marcuño, Germán; Soares-da-Silva, Patrício

    2014-01-01

    Background Latrunculin A microperfusion of the hippocampus induces acute epileptic seizures and long-term biochemical changes leading to spontaneous seizures. This study tested the effect of eslicarbazepine acetate (ESL), a novel antiepileptic drug, on latrunculin A-induced acute and chronic seizures, and changes in brain amino acid extracellular levels. Hippocampi of Swiss mice were continuously perfused with a latrunculin A solution (4 μM, 1 μl/min, 7 h/day) with continuous EEG and videotap...

  7. Radiobiology effects of radiation-induced horseradish peroxidase/indole-3-acetic suicide gene expression in lung cancer cells

    International Nuclear Information System (INIS)

    Objective: To detect specific cell killing effect of radiation combined with horseradish peroxidase (HRP)/indole-3-acetic (IAA) suicide gene therapy controlled by a novel radio-inducible and cancer-specific chimeric gene promoter in lung cancer. Methods: We constructed a plasmid expressing HRP enzyme under the control of chimeric human telomerase reverse transcriptase (hTERT) promoter carrying 6 CArG elements, a plasmid expressing HRP enzyme under the control of hTERT promoter carrying single CArG element, and two control plasmids, which named pE6-hTERT-HRP, phTERT-HRP, pControl-HRP, and pControlluc, respectively. After radiation, the proliferation inhibition and apoptosis induction effect of each type of plasmid in lung cancer cells (A549, SPC-A1) and normal lung cells (hEL) was detected by cell counting and Annexin V-FITC staining. The change of radiosensitivity of lung cancer cells with plasmid system was also detected by clonogenic assays. Results: After a single dose radiation of 6 Gy,the average proliferation inhibition rates of pE6-hTERT-HRP, phTERT-HRP, pControl-HRP, and pControlluc systems were 72.92% ,40.60% , 51.00% and 25.19% (F= 67.31, P< 0.01) in A549 cells, 64.63%, 30.02%, 48.23% and 23.16% (F=64.94, P< 0.01) in SPC-A1 cells, and 20.81%, 18.05%, 44.20% and 18.32% (F=52.19, P<0.01) in normal hEL cells, respectively. The average early apoptosis rates of these four plasmid systems were 36.63%, 22.30%, 24.33% and 12.53% (F =50.99, P <0.01) in A549 cells, 33.73%, 17.37%, 22.43% and 11.20% (F = 20. 76, P < 0.01) in SPC-A1 cells, and 13.53 %, 12.5%, 21.93% and 12.16% (F = 15.08, P < 0.01) in normal hEL cells,respectively. The sensitizing enhancement ratios of the four plasmid systems were 3.45, 2.29, 3.05 and 1.21 in A549 cells, while 2.68, 2.15, 3.05 and 1.21 in SPC-A1 cells, respectively. Conclusions: The new suicide gene system controlled by chimeric promoter may provide a novel therapeutic modality for lung cancer. (authors)

  8. Combined therapy with mutant-selective EGFR inhibitor and Met kinase inhibitor for overcoming erlotinib resistance in EGFR-mutant lung cancer.

    Science.gov (United States)

    Nakagawa, Takayuki; Takeuchi, Shinji; Yamada, Tadaaki; Nanjo, Shigeki; Ishikawa, Daisuke; Sano, Takako; Kita, Kenji; Nakamura, Takahiro; Matsumoto, Kunio; Suda, Kenichi; Mitsudomi, Tetsuya; Sekido, Yoshitaka; Uenaka, Toshimitsu; Yano, Seiji

    2012-10-01

    Although the EGF receptor tyrosine kinase inhibitors (EGFR-TKI) erlotinib and gefitinib have shown dramatic effects against EGFR mutant lung cancer, patients become resistant by various mechanisms, including gatekeeper EGFR-T790M mutation, Met amplification, and HGF overexpression, thereafter relapsing. Thus, it is urgent to develop novel agents to overcome EGFR-TKI resistance. We have tested the effects of the mutant-selective EGFR-TKI WZ4002 and the mutant-selective Met-TKI E7050 on 3 EGFR mutant lung cancer cell lines resistant to erlotinib by different mechanisms: PC-9/HGF cells with an exon 19 deletion, H1975 with an L858R mutation, and HCC827ER with an exon 19 deletion, with acquired resistance to erlotinib because of HGF gene transfection, gatekeeper T790M mutation, and Met amplification, respectively. WZ4002 inhibited the growth of H1975 cells with a gatekeeper T790M mutation, but did not inhibit the growth of HCC827ER and PC-9/HGF cells. HGF triggered the resistance of H1975 cells to WZ4002, whereas E7050 sensitized HCC827ER, PC-9/HGF, and HGF-treated H1975 cells to WZ4002, inhibiting EGFR and Met phosphorylation and their downstream molecules. Combined treatment potently inhibited the growth of tumors induced in severe-combined immunodeficient mice by H1975, HCC827ER, and PC-9/HGF cells, without any marked adverse events. These therapeutic effects were associated with the inhibition of EGFR and Met phosphorylation in vivo. The combination of a mutant-selective EGFR-TKI and a Met-TKI was effective in suppressing the growth of erlotinib-resistant tumors caused by gatekeeper T790M mutation, Met amplification, and HGF overexpression. Further evaluations in clinical trials are warranted. PMID:22844075

  9. The scaffolding protein NHERF1 sensitizes EGFR-dependent tumor growth, motility and invadopodia function to gefitinib treatment in breast cancer cells.

    Science.gov (United States)

    Bellizzi, Antonia; Greco, Maria Raffaella; Rubino, Rosa; Paradiso, Angelo; Forciniti, Stefania; Zeeberg, Katrine; Cardone, Rosa Angela; Reshkin, Stephan Joel

    2015-03-01

    Triple negative breast cancer (TNBC) patients cannot be treated with endocrine therapy or targeted therapies due to lack of related receptors. These patients overexpress the epidermal growth factor receptor (EGFR), but are resistant to tyrosine kinase inhibitors (TKIs) and anti-EGFR therapies. Mechanisms suggested for resistance to TKIs include EGFR independence, mutations and alterations in EGFR and in its downstream signalling pathways. Ligand-induced endocytosis and degradation of EGFR play important roles in the downregulation of the EGFR signal suggesting that its activity could be regulated by targeting its trafficking. Evidence in normal cells showing that the scaffolding protein Na+/H+ exchanger regulatory factor 1 (NHERF1) can associate with EGFR to regulate its trafficking, led us to hypothesize that NHERF1 expression levels could regulate EGFR trafficking and functional expression in TNBC cells and, in this way, modulate its role in progression and response to treatment. We investigated the subcellular localization of NHERF1 and its interaction with EGFR in a metastatic basal like TNBC cell model, MDA-MB‑231, and the role of forced NHERF1 overexpression and/or stimulation with EGF on the sensitivity to EGFR specific TKI treatment with gefitinib. Stimulation with EGF induces an interaction of NHERF1 with EGFR to regulate its localization, degradation and function. NHERF1 overexpression is sufficient to drive its interaction with EGFR in non-stimulated conditions, inhibits EGFR degradation and increases its retention time in the plasma membrane. Importantly, NHERF1 overexpression strongly sensitized the cell to the pharmacological inhibition by gefitinib of EGFR-driven growth, motility and invadopodia-dependent ECM proteolysis. The further determination of how the NHERF1‑EGFR interaction is regulated may improve our understanding of TNBC resistance to the action of existing anticancer drugs.

  10. Missense Mutations in Exons 18–24 of EGFR in Hepatocellular Carcinoma Tissues

    Directory of Open Access Journals (Sweden)

    Ravat Panvichian

    2015-01-01

    Full Text Available Epidermal growth factor receptor (EGFR, a transmembrane tyrosine kinase receptor, plays important roles in various cancers. In nonsmall cell lung cancer (NSCLC, EGFR mutations cluster around the ATP-binding pocket (exons 18–21 and some of these mutations activate the kinase and induce an increased sensitivity to EGFR-tyrosine kinase inhibitors. Nevertheless, data of EGFR mutations in HCC are limited. In this study, we investigated EGFR expression by immunohistochemistry and EGFR mutations (exons 18–24 by PCR cloning and sequencing. EGFR overexpression in HCC and matched nontumor tissues were detected in 13/40 (32.5% and 10/35 (28.6%, respectively. Moreover, missense and silent mutations were detected in 13/33 (39.4% and 11/33 (33.3% of HCC tissues, respectively. The thirteen different missense mutations were p.L730P, p.V742I, p.K757E, p.I780T, p.N808S, p.R831C, p.V851A, p.V897A, p.S912P, p.P937L, p.T940A, p.M947V, and p.M947T. We also found already known SNP, p.Q787Q (CAG>CAA, in 13/33 (39.4% of HCC tissues. However, no significant association was detected between EGFR mutations and EGFR overexpression, tissue, age, sex, tumor size, AFP, HBsAg, TP53, and Ki-67. Further investigation is warranted to validate the frequency and activity of these missense mutations, as well as their roles in HCC tumorigenesis and in EGFR-targeted therapy.

  11. Co-targeting ALK and EGFR parallel signaling in oral squamous cell carcinoma.

    Science.gov (United States)

    Gonzales, Cara B; De La Chapa, Jorge J; Saikumar, Pothana; Singha, Prajjal K; Dybdal-Hargreaves, Nicholas F; Chavez, Jeffery; Horning, Aaron M; Parra, Jamie; Kirma, Nameer B

    2016-08-01

    Squamous cell carcinoma (SCC) comprises 90% of all head and neck cancers and has a poor survival rate due to late-stage disease that is refractive to traditional therapies. Epidermal growth factor receptor (EGFR) is over-expressed in greater than 80% of head and neck SCC (HNSCC). However, EGFR targeted therapies yielded little to no efficacy in clinical trials. This study investigated the efficacy of co-targeting EGFR and the anaplastic lymphoma kinase (ALK) whose promoter is hypomethylated in late-stage oral SCC (OSCC). We observed increased ALK activity in late-stage human OSCC tumors and invasive OSCC cell lines. We also found that while ALK inhibition alone had little effect on proliferation, co-targeting ALK and EGFR significantly reduced OSCC cell proliferation in vitro. Further analysis showed significant efficacy of combined treatment in HSC3-derived xenografts resulting in a 30% decrease in tumor volumes by 14days (panalysis showed that co-targeting ALK and EGFR significantly reduced EGFR phosphorylation (Y1148) in HSC3 cells but not Cal27 cells. ALK and EGFR downstream signaling interactions are also demonstrated by Western blot analysis in which lone EGFR and ALK inhibitors attenuated AKT activity whereas co-targeting ALK and EGFR completely abolished AKT activation. No effects were observed on ERK1/2 activation. STAT3 activity was significantly induced by lone ALK inhibition in HSC3 cells and to a lower extent in Cal27 cells. Together, these data illustrate that ALK inhibitors enhance anti-tumor activity of EGFR inhibitors in susceptible tumors that display increased ALK expression, most likely through abolition of AKT activation. PMID:27424178

  12. Lead Acetate-induced Histopathological Changes in the Gills and Digestive System of Silver Sailfin Molly (Poecilia latipinna

    Directory of Open Access Journals (Sweden)

    Mariam Mahmoud Sharaf

    2011-01-01

    Full Text Available This study aims to investigate the effects of a single sublethal concentration of lead acetate on the gills and digestive system of the silver mollies. After LC50 determination, twenty five mollies were randomly chosen and divided into two groups. The first one served as control; while the second group exposed to 0.8 mg lead acetate/liter of H2O for 96 h. Afterwards fish were anesthetized, dissected out and the gills, liver, pancreas, stomach and intestine were processed for paraffin embedding, stained with haematoxylin and eosin and examined by light microscopy. Lead acetate-exposed fish exhibited a decrease of swimming activity and brilliant silvery body color, accumulation of lead acetate on ovarian surface and an increased secretion of mucus from gills and skin. The gills showed hyperplasia, hypertrophy and destruction of the lamellar architecture, fusion of lamellae and lamellar clubbing. The livers showed disarrangement of hepatic cords, shrinkage of hepatocytes and dilatation of liver sinusoids and extravasation of blood. Hepatopancreas damage included loss of contact between hepatocytes and pancreocytes, lysis of pancreocyte membranes and appearance of pyknotic/apoptotic nuclei. The exocrine pancreas revealed necrosis, increased adipocytes and atrophy of pancreatic acini. The stomach exhibited irregularity, shrinkage and fusion of its microvilli, pyknotic/apoptotic nuclei of microvilli epithelium and atrophy of submucosal zone. The intestinal damage included fusion of intestinal microvilli, necrosis and irregularities of the microvilli cells, microvilli loss, flattening and hypertrophy. The study concluded that lead acetate exposure resulted in severe histopathological changes in the gills and in the selected digestive organs of silver mollies.

  13. Aristolochia manshuriensis Kom ethyl acetate extract protects against high-fat diet-induced non-alcoholic steatohepatitis by regulating kinase phosphorylation in mouse

    Science.gov (United States)

    Kwak, Dong Hoon; Kim, Ji-Su; Chang, Kyu-Tae

    2016-01-01

    Aristolochia manshuriensis Kom (AMK) is an herb used as a traditional medicine; however, it causes side effects such as nephrotoxicity and carcinogenicity. Nevertheless, AMK can be applied in specific ways medicinally, including via ingestion of low doses for short periods of time. Non-alcoholic steatohepatitis (NASH) induced the hepatocyte injury and inflammation. The protective effects of AMK against NASH are unclear; therefore, in this study, the protective effects of AMK ethyl acetate extract were investigated in a high-fat diet (HFD)-induced NASH model. We found decreased hepatic steatosis and inflammation, as well as increased levels of lipoproteins during AMK extract treatment. We also observed decreased hepatic lipid peroxidation and triglycerides, as well as suppressed hepatic expression of lipogenic genes in extract-treated livers. Treatment with extract decreased the activation of c-jun N-terminal kinase 1/2 (JNK1/2) and increased the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2). These results demonstrate that the protective effect of the extract against HFD-induced NASH occurred via reductions in reactive oxygen species production, inflammation suppression, and apoptosis related to the suppression of JNK1/2 activation and increased ERK1/2 phosphorylation. Taken together, these results indicate that that ethyl acetate extract of AMK has potential therapeutic effects in the HFD-induced NASH mouse model. PMID:26726030

  14. Acetate reduces microglia inflammatory signaling in vitro

    OpenAIRE

    Soliman, Mahmoud L; Puig, Kendra L.; Combs, Colin K.; Rosenberger, Thad A.

    2012-01-01

    Acetate supplementation increases brain acetyl-CoA and histone acetylation and reduces lipopolysaccharide (LPS)-induced neuroglial activation and interleukin (IL)-1β expression in vivo. To determine how acetate imparts these properties, we tested the hypothesis that acetate metabolism reduces inflammatory signaling in microglia. To test this, we measured the effect acetate treatment had on cytokine expression, mitogen-activated protein kinase (MAPK) signaling, histone H3 at lysine 9 acetylati...

  15. EGFR-targeted TRAIL and a Smac mimetic synergize to overcome apoptosis resistance in KRAS mutant colorectal cancer cells.

    Directory of Open Access Journals (Sweden)

    Yvonne Möller

    Full Text Available TRAIL is a death receptor ligand that induces cell death preferentially in tumor cells. Recombinant soluble TRAIL, however, performs poorly as an anti-cancer therapeutic because oligomerization is required for potent biological activity. We previously generated a diabody format of tumor-targeted TRAIL termed Db(αEGFR-scTRAIL, comprising single-stranded TRAIL molecules (scTRAIL and the variable domains of a humanized variant of the EGFR blocking antibody Cetuximab. Here we define the bioactivity of Db(αEGFR-scTRAIL with regard to both EGFR inhibition and TRAIL receptor activation in 3D cultures of Caco-2 colorectal cancer cells, which express wild-type K-Ras. Compared with conventional 2D cultures, Caco-2 cells displayed strongly enhanced sensitivity toward Db(αEGFR-scTRAIL in these 3D cultures. We show that the antibody moiety of Db(αEGFR-scTRAIL not only efficiently competed with ligand-induced EGFR function, but also determined the apoptotic response by specifically directing Db(αEGFR-scTRAIL to EGFR-positive cells. To address how aberrantly activated K-Ras, which leads to Cetuximab resistance, affects Db(αEGFR-scTRAIL sensitivity, we generated stable Caco-2tet cells inducibly expressing oncogenic K-Ras(G12V. In the presence of doxycycline, these cells showed increased resistance to Db(αEGFR-scTRAIL, associated with the elevated expression of the anti-apoptotic proteins cIAP2, Bcl-xL and FlipS. Co-treatment of cells with the Smac mimetic SM83 restored the Db(αEGFR-scTRAIL-induced apoptotic response. Importantly, this synergy between Db(αEGFR-scTRAIL and SM83 also translated to 3D cultures of oncogenic K-Ras expressing HCT-116 and LoVo colorectal cancer cells. Our findings thus support the notion that Db(αEGFR-scTRAIL therapy in combination with apoptosis-sensitizing agents may be promising for the treatment of EGFR-positive colorectal cancers, independently of their KRAS status.

  16. Foreign Body Granulomas Induced by Intramuscular Leuprorelin Acetate Injection for Prostate Cancer: Clinical Mimics of Soft Tissue Sarcoma

    Directory of Open Access Journals (Sweden)

    Khin Thway

    2015-01-01

    Full Text Available We describe two cases of florid, foreign body granulomatous reaction occurring in the upper arms of males in their eighth decade, who were undergoing treatment with depot injection of leuprorelin acetate for prostatic carcinoma. These patients presented with rapidly enlarging extremity soft tissue masses and were referred to a tertiary sarcoma center with clinical suspicion of a primary soft tissue neoplasm. The occurrence of injection site granulomas secondary to leuprorelin acetate administration is rarely known outside the urological and dermatological communities, and their recognition is important due to the spectrum of clinical differential diagnoses and potential for diagnostic confusion with metastatic prostatic cancer and primary sarcoma and in order to avoid unnecessary stress and clinical intervention for patients.

  17. Phorbol 12-myristate 13-acetate, ionomycin or ouabain, and raised extracellular magnesium induce proliferation of chicken heart mesenchymal cells.

    OpenAIRE

    Balk, S D; Morisi, A; Gunther, H S

    1984-01-01

    Cultured chicken heart mesenchymal cells are proliferatively quiescent at low densities in medium containing plasma at 10%. Mitogenic hormones like epidermal growth factor and insulin-like growth factors cause these cells to proliferate very actively, as does infection with avian sarcoma viruses, erythroblastosis virus, or myelocytomatosis virus. We have found that the combination of phorbol 12-myristate 13-acetate (PMA), ionomycin or ouabain, and raised extracellular magnesium, likewise, cau...

  18. Study of carrier blocking property of poly-linalyl acetate thin layer by electric-field-induced optical second-harmonic generation measurement

    Science.gov (United States)

    Taguchi, Dai; Manaka, Takaaki; Iwamoto, Mitsumasa; Anderson, Liam J.; Jacob, Mohan V.

    2014-02-01

    By using electric-field-induced optical second-harmonic generation (EFISHG) measurement, we studied the carrier-blocking property of poly-linalyl acetate (PLA) thin layers sandwiched in indium-zinc-oxide (IZO)/PLA/C60/Al double-layer diodes. Results showed that the PLA layer totally blocks electrons crossing the C60 layer, and also blocks holes entering from the IZO layer. The EFISHG measurement effectively substantiates the hole-blocking electron-blocking property of the PLA layer sandwiched in double layer diodes.

  19. Anti-epidermal growth factor receptor monoclonal antibody cetuximab inhibits EGFR/HER-2 heterodimerization and activation.

    Science.gov (United States)

    Patel, Dipa; Bassi, Rajiv; Hooper, Andrea; Prewett, Marie; Hicklin, Daniel J; Kang, Xiaoqiang

    2009-01-01

    Human carcinomas frequently express one or more members of the epidermal growth factor receptor family. Two family members, epidermal growth factor receptor (EGFR) and c-erbB2/neu (HER2), homodimerize or heterodimerize upon activation with ligand and trigger potent mechanisms of cellular proliferation, differentiation and migration. In this study, we examined the effect of the anti-EGFR monoclonal antibody Erbitux (cetuximab) on human tumor cells expressing both EGFR and HER2. Investigation of the effect of cetuximab on the activation of EGFR-EGFR, EGFR-HER2 and HER2-HER2 homodimers and heterodimers was conducted using the NCI-N87 human gastric carcinoma cell line. Treatment of NCI-N87 cells with cetuximab completely inhibited formation of EGFR-EGFR homodimers and EGFR-HER2 heterodimers. Activation of HER2-HER2 homodimers was not appreciably stimulated by exogenous ligand and was not inhibited by cetuximab treatment. Furthermore, cetuximab inhibited EGF-induced EGFR and HER2 phosphorylation in CAL27, NCI-H226 and NCI-N87 cells. The activation of downstream signaling molecules such as AKT, MAPK and STAT-3 were also inhibited by cetuximab in these cells. To examine the effect of cetuximab on the growth of tumors in vivo, athymic mice bearing established NCI-N87 or CAL27 xenografts were treated with cetuximab (1 mg, i.p., q3d). The growth of NCI-N87 and CAL27 tumors was significantly inhibited with cetuximab therapy compared to the control groups (p<0.0001 in both cases). In the CAL27 xenograft model, tumor growth inhibition by cetuximab treatment was similar to that by cetuximab and trastuzumab combination treatment. Immunohistological analysis of cetuximab-treated tumors showed a decrease in EGFR-HER2 signaling and reduced tumor cell proliferation. These results suggest that cetuximab may be useful in the treatment of carcinomas co-expressing EGFR and HER2. PMID:19082474

  20. Clostebol acetate

    Directory of Open Access Journals (Sweden)

    Elisabetta Maccaroni

    2011-08-01

    Full Text Available The title compound, C21H29ClO3 [systematic name (8R,9S,10R,13S,14S,17S-4-chloro-3-oxoandrost-4-en-17β-yl acetate], is a 4-chloro derivative of testosterone, used as an anabolic androgenic agent or applied topically in ophthalmological and dermatological treatments. The absolute configurations at positions 8, 9, 10, 13, 14 and 17 were established by refinement of the Flack parameter as R, S, R, S, S, and S, respectively. Rings B and C of the steroid ring system adopt chair conformations, ring A has a half-chair conformation, while ring D is in a C13 envelope conformation. Ring B and C, and C and D are trans fused. In the crystal, molecules are linked by a weak C—H...O interaction.

  1. Combined effects of EGFR tyrosine kinase inhibitors and vATPase inhibitors in NSCLC cells

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hyeon-Ok [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Hong, Sung-Eun [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Kim, Chang Soon [Department of Microbiological Engineering, Kon-Kuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 143–701 (Korea, Republic of); Park, Jin-Ah; Kim, Jin-Hee; Kim, Ji-Young; Kim, Bora [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Chang, Yoon Hwan; Hong, Seok-Il; Hong, Young Jun [Department of Laboratory Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Park, In-Chul, E-mail: parkic@kirams.re.kr [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Lee, Jin Kyung, E-mail: jklee@kirams.re.kr [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Department of Laboratory Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of)

    2015-08-15

    Despite excellent initial clinical responses of non-small cell lung cancer (NSCLC) patients to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), many patients eventually develop resistance. According to a recent report, vacuolar H + ATPase (vATPase) is overexpressed and is associated with chemotherapy drug resistance in NSCLC. We investigated the combined effects of EGFR TKIs and vATPase inhibitors and their underlying mechanisms in the regulation of NSCLC cell death. We found that combined treatment with EGFR TKIs (erlotinib, gefitinib, or lapatinib) and vATPase inhibitors (bafilomycin A1 or concanamycin A) enhanced synergistic cell death compared to treatments with each drug alone. Treatment with bafilomycin A1 or concanamycin A led to the induction of Bnip3 expression in an Hif-1α dependent manner. Knock-down of Hif-1α or Bnip3 by siRNA further enhanced cell death induced by bafilomycin A1, suggesting that Hif-1α/Bnip3 induction promoted resistance to cell death induced by the vATPase inhibitors. EGFR TKIs suppressed Hif-1α and Bnip3 expression induced by the vATPase inhibitors, suggesting that they enhanced the sensitivity of the cells to these inhibitors by decreasing Hif-1α/Bnip3 expression. Taken together, we conclude that EGFR TKIs enhance the sensitivity of NSCLC cells to vATPase inhibitors by decreasing Hif-1α/Bnip3 expression. We suggest that combined treatment with EGFR TKIs and vATPase inhibitors is potentially effective for the treatment of NSCLC. - Highlights: • Co-treatment with EGFR TKIs and vATPase inhibitors induces synergistic cell death • EGFR TKIs enhance cell sensitivity to vATPase inhibitors via Hif-1α downregulation • Co-treatment of these inhibitors is potentially effective for the treatment of NSCLC.

  2. Mitochondrial translocation of EGFR regulates mitochondria dynamics and promotes metastasis in NSCLC.

    Science.gov (United States)

    Che, Ting-Fang; Lin, Ching-Wen; Wu, Yi-Ying; Chen, Yu-Ju; Han, Chia-Li; Chang, Yih-leong; Wu, Chen-Tu; Hsiao, Tzu-Hung; Hong, Tse-Ming; Yang, Pan-Chyr

    2015-11-10

    Dysfunction of the mitochondria is well-known for being associated with cancer progression. In the present study, we analyzed the mitochondria proteomics of lung cancer cell lines with different invasion abilities and found that EGFR is highly expressed in the mitochondria of highly invasive non-small-cell lung cancer (NSCLC) cells. EGF induces the mitochondrial translocation of EGFR; further, it leads to mitochondrial fission and redistribution in the lamellipodia, upregulates cellular ATP production, and enhances motility in vitro and in vivo. Moreover, EGFR can regulate mitochondrial dynamics by interacting with Mfn1 and disturbing Mfn1 polymerization. Overexpression of Mfn1 reverses the phenotypes resulting from EGFR mitochondrial translocation. We show that the mitochondrial EGFR expressions are higher in paired samples of the metastatic lymph node as compared with primary lung tumor and are inversely correlated with the overall survival in NSCLC patients. Therefore, our results demonstrate that besides the canonical role of EGFR as a receptor tyrosine, the mitochondrial translocation of EGFR may enhance cancer invasion and metastasis through regulating mitochondria dynamics.

  3. In Vivo Assessment of the Regulation of Transforming Growth Factor Alpha, Epidermal Growth Factor (EGF), and EGF Receptor in the Human Endometrium by Medroxyprogesterone Acetate

    OpenAIRE

    Fernando M. Reis; Lhullier, Cintia; Edelweiss, Maria Isabel; Spritzer, Poli Mara

    2005-01-01

    Purpose: The present study evaluated the in vivo effect of medroxyprogesterone acetate (MPA) on the localization of immunoreactive transforming growth factor alpha (TGFα), epidermal growth factor (EGF), and their common receptor (EGF-R) in the human endometrium.

  4. Targeting the EGFR/PCNA signaling suppresses tumor growth of triple-negative breast cancer cells with cell-penetrating PCNA peptides.

    Directory of Open Access Journals (Sweden)

    Yung-Luen Yu

    Full Text Available Tyrosine 211 (Y211 phosphorylation of proliferation cell nuclear antigen (PCNA coincides with pronounced cancer cell proliferation and correlates with poor survival of breast cancer patients. In epidermal growth factor receptor (EGFR tyrosine kinase inhibitor (TKI-resistant cells, both nuclear EGFR (nEGFR expression and PCNA Y211 phosphorylation are increased. Moreover, the resistance to EGFR TKI is a major clinical problem in treating EGFR-overexpressing triple-negative breast cancer (TNBC. Thus, effective treatment to combat resistance is urgently needed. Here, we show that treatment of cell-penetrating PCNA peptide (CPPP inhibits growth and induces apoptosis of human TNBC cells. The Y211F CPPP specifically targets EGFR and competes directly for PCNA tyrosine Y211 phosphorylation and prevents nEGFR from binding PCNA in vivo; it also suppresses tumor growth by sensitizing EGFR TKI resistant cells, which have enhanced nEGFR function and abrogated classical EGFR membrane signaling. Furthermore, we identify an active motif of CPPP, RFLNFF (RF6 CPPP, which is necessary and sufficient to inhibit TKI-resistant TNBC cell growth of orthotopic implanted tumor in mice. Finally, the activity of its synthetic retro-inverted derivative, D-RF6 CPPP, on an equimolar basis, is more potent than RF6 CPPP. Our study reveals a drug candidate with translational potential for the future development of safe and effective therapeutic for EGFR TKI resistance in TNBC.

  5. Suppression of PAI-1 expression through inhibition of the EGFR-mediated signaling cascade in rat kidney fibroblast by ascofuranone.

    Science.gov (United States)

    Cho, Hyun-Ji; Kang, Jeong-Han; Kim, Teoan; Park, Kwang-Kyun; Kim, Cheorl-Ho; Lee, In-Seon; Min, Kwan-Sik; Magae, Junji; Nakajima, Hiroo; Bae, Young-Seuk; Chang, Young-Chae

    2009-05-15

    Fibrosis in glomerulosclerosis causes progressive loss of renal function. Transforming growth factor (TGF)-beta, one of the major profibrotic cytokines, induces the synthesis of plasminogen activator inhibitor (PAI)-1, a factor that plays a crucial role in the development of fibrosis. Here, we found that an isoprenoid antibiotic, ascofuranone, suppresses expression of profibrotic factors including matrix proteins and PAI-1 induced by TGF-beta in renal fibroblasts. Ascofuranone selectively inhibits phosphorylation of epidermal growth factor receptor (EGFR), and downstream kinases such as Raf-1, MEK-1/2, and ERK-1/2. PAI-1 transcription also is suppressed by treatment with kinase inhibitors for MEK-1/2 or EGFR, and with small interfering RNA for EGFR. Ascofuranone inhibits cellular metalloproteinase activity, and an inhibitor of metalloproteinases suppresses EGFR phosphorylation and PAI-1 transcription. These results suggest that ascofuranone suppresses expression of profibrotic factors through the inhibition of an EGFR-dependent signal transduction pathway activated by metalloproteinases.

  6. Epitope mapping of epidermal growth factor receptor (EGFR) monoclonal antibody and induction of growth-inhibitory polyclonal antibodies by vaccination with EGFR mimotope.

    Science.gov (United States)

    Navari, Mohsen; Zare, Mehrak; Javanmardi, Masoud; Asadi-Ghalehni, Majid; Modjtahedi, Helmout; Rasaee, Mohammad Javed

    2014-10-01

    One of the proposed approaches in cancer therapy is to induce and direct the patient's own immune system against cancer cells. In this study, we determined the epitope mapping of the rat anti-human epidermal growth factor receptor (EGFR) monoclonal antibody ICR-62 using a phage display of random peptide library and identified a 12 amino acids peptide, which was recognized as a mimotope. The peptide was synthesized and conjugated to bovine serum albumin (BSA) as carrier protein (P-BSA). We have shown that ICR-62 can react specifically with P-BSA as well as native EGFR. Two rabbits were immunized either by BSA or P-BSA and the rabbits IgGs were purified and examined for binding to the antigens, mimotope and the EGFR protein purified from the EGFR overexpressing A431 cell line. We showed that the rabbit IgG generated against the mimotope is capable of inhibiting the growth of A431 cells by 15%, but does not have any effect on the growth of EGFR-negative MDA-MB-453 cell line in vitro. Our results support the need for further investigations on the potential of vaccination with either mimotope of the EGFR or epitope displayed on the surface of phage particles for use in active immunotherapy of cancer.

  7. Molecular epidemiology of lung cancer and geographic variations with special reference to EGFR mutations.

    Science.gov (United States)

    Mitsudomi, Tetsuya

    2014-08-01

    Lung cancer is a leading cause of cancer-related mortality in many countries. Although recent advances in targeted therapy against driver oncogenes have significantly improved patient outcome, cure of this disease is still exceptional. Although tobacco is a known cause of lung cancer, not all smokers develop lung cancer, and conversely many patients, especially Asian female patients with lung cancer, are lifetime never-smokers. Therefore, efforts to understand the basis for different susceptibilities to lung cancer among individuals with different genetic, biologic, ethnic, and social backgrounds are important to help develop effective preventive measures. Lung cancer in never-smokers has many different characteristics to lung cancer in smokers, such as adenocarcinoma predominance and high frequency of epidermal growth factor receptor (EGFR) mutation yet low number of genetic changes. Epidemiologic studies suggest that East Asians are more susceptible to smoking-unrelated lung cancer but less susceptible to smoking-related lung cancer compared with Caucasians. Mutations in the EGFR gene are more common in Asian females and never-smokers. Our case-control study suggests that EGFR mutation occurs independent of smoking, and that the apparent low frequency of EGFR mutations in smokers may be the result of dilution by smoking-related lung cancer. The frequencies of three EGFR gene polymorphisms associated with increased protein expression are significantly different between East Asians and Caucasians, favoring lower protein expression in East Asians. Although these may be associated with preferred expression of the EGFR mutant allele, it is difficult to explain the frequent EGFR mutation in Asian patients. Genome wide association studies (GWAS) revealed several loci related to lung cancer susceptibility. In the future, GWAS may identify loci that are specifically related to EGFR-targeted carcinogenesis, leading to identification of carcinogens that induce EGFR

  8. Effect of melengestrol acetate on development of 3-methylindole-induced pulmonary edema and emphysema in sheep.

    OpenAIRE

    Popp, J D; McAllister, T.A.; Kastelic, J P; Majak, W; Ayroud, M; VanderKop, M A; Karren, D; Yost, G S; Cheng, K J

    1998-01-01

    The involvement of melengestrol acetate (MGA) in susceptibility to developing pulmonary edema and emphysema following oral administration of 3-methylindole (3MI) was investigated using 10 Suffolk ewes receiving 0 or 0.15 mg of MGA daily (n = 5). Blood, urine and ruminal fluid were collected immediately prior to 3MI dosing (0.2 g/kg BW) and 1, 2, 3, 4, 5, 6, 12 and 24 h (blood); 3, 6, 9, 12 and 15 h (urine) and 1, 2, 3 and 12 h (ruminal fluid) afterward. Ewes receiving MGA experienced earlier ...

  9. AZD9291 overcomes T790 M-mediated resistance through degradation of EGFR(L858R/T790M) in non-small cell lung cancer cells.

    Science.gov (United States)

    Ku, Bo Mi; Bae, Yeon-Hee; Koh, Jiae; Sun, Jong-Mu; Lee, Se-Hoon; Ahn, Jin Seok; Park, Keunchil; Ahn, Myung-Ju

    2016-08-01

    The discovery of activating mutations of epidermal growth factor receptor (EGFR) has resulted in the development of more effective treatments for non-small cell lung cancer (NSCLC). Although first-generation EGFR tyrosine kinase inhibitors (EGFR TKIs) provide significant clinical benefit, acquired resistance often occurs, most commonly (>50 %) via a T790 M resistance mutation. Although AZD9291 is selective for both T790 M and activating EGFR mutations over wild-type EGFR, it is highly active when T790 M is present, especially EGFR(L858R/T790M), and modestly active when T790 M is absent. The aim of this study was to elucidate the underlying mechanism of the high sensitivity of NSCLC cells harboring EGFR(L858R/T790M) to AZD9291. In H1975 cells harboring EGFR(L858R/T790M), AZD9291 potently inhibited cellular growth and EGFR signaling pathways together with depletion of mutant EGFR protein. AZD9291-induced depletion of EGFR(L858R/T790M) protein was abrogated through inhibition of the proteasome with MG132. However, AZD9291 had no effect on protein levels of EGFR(WT) and EGFR(L858R). In addition, AZD9291 induced apoptosis and caused expression changes in cell cycle-related genes. Moreover, oral administration of AZD9291 as a single agent induced tumor regression in vivo in a H1975 tumor xenograft model and reduced EGFR(L858R/T790M) protein levels in xenograft tumors. Taken together, our results provide a potential mechanism for the sensitivity of EGFR(L858R/T790M) cells to AZD9291 and suggest that AZD9291 may be effective in cases of T790 M-positive EGFR resistance. PMID:27044261

  10. The role of calcium in growth induced by indole-3-acetic acid and gravity in the leaf-sheath pulvinus of oat (Avena sativa)

    Science.gov (United States)

    Brock, T. G.; Burg, J.; Ghosheh, N. S.; Kaufman, P. B.

    1992-01-01

    Leaf-sheath pulvini of excised segments from oat (Avena sativa L.) were induced to grow by treatment with 10 micromoles indole-3-acetic acid (IAA), gravistimulation, or both, and the effects of calcium, EGTA, and calcium channel blockers on growth were evaluated. Unilaterally applied calcium (10 mM CaCl2) significantly inhibited IAA-induced growth in upright pulvini but had no effect on growth induced by either gravity or gravity plus IAA. Calcium alone had no effect on upright pulvini. The calcium chelator EGTA alone (10 mM) stimulated growth in upright pulvini. However, EGTA had no effect on either IAA- or gravity-induced growth but slightly diminished growth in IAA-treated gravistimulated pulvini. The calcium channel blockers lanthanum chloride (25 mM), verapamil (2.5 mM), and nifedipine (2.5 mM) greatly inhibited growth as induced by IAA (> or = 50% inhibition) or IAA plus gravity (20% inhibition) but had no effect on gravistimulated pulvini. Combinations of channel blockers were similar in effect on IAA action as individual blockers. Since neither calcium ions nor EGTA significantly affected the graviresponse of pulvini, we conclude that apoplastic calcium is unimportant in leaf-sheath pulvinus gravitropism. The observation that calcium ions and calcium channel blockers inhibit IAA-induced growth, but have no effect on gravistimulated pulvini, further supports previous observations that gravistimulation alters the responsiveness of pulvini to IAA.

  11. Transduced PEP-1-ribosomal protein S3 (rpS3) ameliorates 12-O-tetradecanoylphorbol-13-acetate-induced inflammation in mice

    International Nuclear Information System (INIS)

    This study investigated the preventive effect of ribosomal protein S3 (rpS3) on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear edema in mice. A cell permeable expression vector PEP-1-rpS3 was constructed. Topical application of the vector markedly inhibited TPA-induced expression levels of cyclooxygenase-2 (COX-2) and pro-inflammatory cytokines. Application of PEP-1-rpS3 also resulted in a significant reduction in the activation of nuclear factor-kappa B (NF-kB) and mitogen-activated protein kinase (MAPK) in TPA-treated ears. These results indicate that PEP-1-rpS3 inhibits inflammatory response cytokines and enzymes by blocking NF-kB and MAPK, prompting the suggestion that PEP-1-rpS3 can be used as a therapeutic agent against skin inflammation.

  12. Discovery of a series of novel phenylpiperazine derivatives as EGFR TK inhibitors

    Science.gov (United States)

    Sun, Juan; Wang, Xin-Yi; Lv, Peng-Cheng; Zhu, Hai-Liang

    2015-09-01

    Human epidermal growth factor receptor (EGFR) is an important drug target that plays a fundamental role in signal transduction pathways in oncology. We report herein the discovery of a novel class of phenylpiperazine derivatives with improved potency toward EGFR. The biological activity of compound 3p as inhibitor of EGFR was further investigated both in vitro and in vivo. Notably, compound 3p exhibited an IC50 in the nanomolar range in A549 cell cultures and induced a cessation of tumor growth with no toxicity, as determined by loss of body weight and death of treated mice. Compoutational docking studies also showed that compound 3p has interaction with EGFR key residues in the active site.

  13. Immunohistochemical detections of EGFR status in NSCLC

    Directory of Open Access Journals (Sweden)

    Jie WANG

    2015-04-01

    Full Text Available Background and objective Patients with non-small cell lung cancer (NSCLC harboring mutations of the epidermal growth factor receptor (EGFR respond well to EGFR-tyrosine kinase inhibitor therapy. Immunohistochemistry (IHC is a simple and widely used technique in clinical pathology laboratories. IHC also features cost effectiveness and rapid detection of EGFR mutations compared with molecular methods. This study aims to determine the accuracy of IHC for EGFR mutation detection in NSCLC. Methods Specimens (obtained from surgery or biopsy from 97 NSCLC cases were stained through IHC with mutation-specific antibodies. The clinicopathological features of patients with positive immunostaining results were analyzed. Positive specimens were subjected to liquid chip technology to detect the actual EGFR status. Forty NSCLC specimens obtained from surgery and confirmed to have EGFR mutations through liquid chip technology were collected. These specimens were then subjected to IHC analyses with mutation-specific antibodies. The sensitivity of IHC in detecting EGFR mutations was calculated. Results Seventeen of the 97 NSCLC specimens were stained positive, and positive results were mostly observed in females, patients with adenocarcinoma, and non-smokers. About 76.9% of specimens with positive IHC results harbored mutations. The sensitivity of IHC was 40% among the 40 cases identified as containing EGFR mutations through liquid chip technology. Conclusion The strong positive immunostaining result is accurate, but the sensitivity of the method may not be optimal and significantly varies in different studies. The widespread application of IHC in clinics must be further investigated.

  14. Naegleria fowleri induces MUC5AC and pro-inflammatory cytokines in human epithelial cells via ROS production and EGFR activation.

    Science.gov (United States)

    Cervantes-Sandoval, Isaac; Serrano-Luna, José de Jesús; Meza-Cervantez, Patricia; Arroyo, Rossana; Tsutsumi, Víctor; Shibayama, Mineko

    2009-11-01

    Naegleria fowleri is an amoeboflagellate responsible for the fatal central nervous system (CNS) disease primary amoebic meningoencephalitis (PAM). This amoeba gains access to the CNS by invading the olfactory mucosa and crossing the cribriform plate. Studies using a mouse model of infection have shown that the host secretes mucus during the very early stages of infection, and this event is followed by an infiltration of neutrophils into the nasal cavity. In this study, we investigated the role of N. fowleri trophozoites in inducing the expression and secretion of airway mucin and pro-inflammatory mediators. Using the human mucoepidermal cell line NCI-H292, we demonstrated that N. fowleri induced the expression of the MUC5AC gene and protein and the pro-inflammatory mediators interleukin-8 (IL-8) and interleukin-1 beta (IL-1 beta), but not tumour necrosis factor-alpha or chemokine c-c motif ligand 11 (eotaxin). Since the production of reactive oxygen species (ROS) is a common phenomenon involved in the signalling pathways of these molecules, we analysed if trophozoites were capable of causing ROS production in NCI-H292 cells by detecting oxidation of the fluorescent probe 2,7-dichlorofluorescein diacetate. NCI-H292 cells generated ROS after 15-30 min of trophozoite stimulation. Furthermore, the expression of MUC5AC, IL-8 and IL-1 beta was inhibited in the presence of the ROS scavenger DMSO. In addition, the use of an epidermal growth factor receptor inhibitor decreased the expression of MUC5AC and IL-8, but not IL-1 beta. We conclude that N. fowleri induces the expression of some host innate defence mechanisms, such as mucin secretion (MUC5AC) and local inflammation (IL-8 and IL-1 beta) in respiratory epithelial cells via ROS production and suggest that these innate immune mechanisms probably prevent most PAM infections.

  15. EGFR as a therapeutic target in glioblastoma

    Directory of Open Access Journals (Sweden)

    David M Siebert

    2012-01-01

    Full Text Available The tyrosine kinase receptor epidermal growth factor receptor (EGFR can be activated by several ligands, thus triggering downstream pathways regulating cell growth and survival. Its dysregula­tion is particularly important for the development and progression of astrocytomas. After the description of its role in glioblastomas (WHO grade IV astrocytomas, an overview on the therapeutic strategies target­ing EGFR is provided. It analyzes the past and ongoing trials concerning the small molecule tyro­sine kinase inhibitors, i.e. gefitinib, erlotinib and the combination therapies, the EGFR vaccina­tion strategies, the antibodies directed against EGFR and finally the intracranially administered EGFR-targeted therapies. As our understanding of the underlying molecular aberrancies in glioblastoma grows, our ability to better target specific subtypes of glioblastoma should improve. Molecular biomarker enriched clinical trials may lead to improved patient outcomes.

  16. Monitoring of Circulating Tumor Cells and Their Expression of EGFR/Phospho-EGFR During Combined Radiotherapy Regimens in Locally Advanced Squamous Cell Carcinoma of the Head and Neck

    Energy Technology Data Exchange (ETDEWEB)

    Tinhofer, Ingeborg, E-mail: ingeborg.tinhofer@charite.de [Translational Radiooncology Laboratory, Department of Radiooncology and Radiotherapy, Charite Campus Mitte, Charite Universitaetsmedizin Berlin, Berlin (Germany); Hristozova, Tsvetana; Stromberger, Carmen [Translational Radiooncology Laboratory, Department of Radiooncology and Radiotherapy, Charite Campus Mitte, Charite Universitaetsmedizin Berlin, Berlin (Germany); KeilhoIz, Ulrich [Department of Hematology and Oncology, Campus Benjamin Franklin, Charite Universitaetsmedizin Berlin, Berlin (Germany); Budach, Volker [Translational Radiooncology Laboratory, Department of Radiooncology and Radiotherapy, Charite Campus Mitte, Charite Universitaetsmedizin Berlin, Berlin (Germany)

    2012-08-01

    Purpose: The numbers of circulating tumor cells (CTCs) and their expression/activation of epidermal growth factor receptor (EGFR) during the course of combined chemo- or bioradiotherapy regimens as potential biomarkers of treatment efficacy in squamous cell carcinoma of the head and neck (SCCHN) were determined. Methods and Materials: Peripheral blood samples from SCCHN patients with locally advanced stage IVA/B disease who were treated with concurrent radiochemotherapy or induction chemotherapy followed by bioradiation with cetuximab were included in this study. Using flow cytometry, the absolute number of CTCs per defined blood volume as well as their expression of EGFR and its phosphorylated form (pEGFR) during the course of treatment were assessed. Results: Before treatment, we detected {>=}1 CTC per 3.75 mL blood in 9 of 31 patients (29%). Basal expression of EGFR was detected in 100% and pEGFR in 55% of the CTC+ cases. The frequency of CTC detection was not influenced by induction chemotherapy. However, the number of CTC+ samples significantly increased after radiotherapy. This radiation-induced increase in CTC numbers was less pronounced when radiotherapy was combined with cetuximab compared to its combination with cisplatin/5-fluorouracil. The former treatment regimen was also more effective in reducing pEGFR expression in CTCs. Conclusions: Definitive radiotherapy regimens of locally advanced SCCHN can increase the number of CTCs and might thus contribute to a systemic spread of tumor cells. Further studies are needed to evaluate the predictive value of the radiation-induced increase in CTC numbers and the persistent activation of the EGFR signalling pathway in individual CTC+ cases.

  17. Glatiramer acetate (GA) prevents TNF-α-induced monocyte adhesion to primary endothelial cells through interfering with the NF-κB pathway

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Guoqian; Zhang, Xueyan; Su, Zhendong; Li, Xueqi, E-mail: xueqili075@yeah.net

    2015-01-30

    Highlights: • GA inhibited TNF-α-induced binding of monocytes to endothelial cells. • GA inhibited the induction of adhesion molecules MCP-1, VCAM-1 and E-selectin. • GA inhibits NF-κB p65 nuclear translocation and transcriptional activity. • GA inhibits TNF-α-induced IκBα degradation. - Abstract: Pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α) is considered to be the major one contributing to the process of development of endothelial dysfunction. Exposure to TNF-α induces the expression of a number of proinflammatory chemokines, such as monocyte chemotactic protein-1 (MCP-1), and adhesion molecules, including vascular adhesion molecule-1 (VCAM-1) and E-selectin, which mediate the interaction of invading monocytes with vascular endothelial cells. Glatiramer acetate (GA) is a licensed clinical drug for treating patients suffering from multiple sclerosis (MS). The effects of GA in vascular disease have not shown before. In this study, we found that GA significantly inhibited TNF-α-induced binding of monocytes to endothelial cells. Mechanistically, we found that GA ameliorated the upregulation of MCP-1, VCAM-1, and E-selectin induced by TNF-α. Notably, this process is mediated by inhibiting the nuclear translocation and activation of NF-κB. Our results also indicate that GA pretreatment attenuates the up-regulation of COX-2 and iNOS. These data suggest that GA might have a potential benefit in therapeutic endothelial dysfunction related diseases.

  18. HIF2α contributes to antiestrogen resistance via positive bilateral crosstalk with EGFR in breast cancer cells

    DEFF Research Database (Denmark)

    Alam, Muhammad Wasi; Persson, Camilla Ulrika; Reinbothe, Susann;

    2016-01-01

    or inhibition of EGFR led to decreased HIF2α levels. This positive and bilateral HIF2-EGFR regulatory crosstalk promotes antiestrogen resistance and, where intrinsic hypoxic resistance exists, therapy itself may exacerbate the problem. Finally, inhibition of HIFs by FM19G11 restores antiestrogen sensitivity......The majority of breast cancers express estrogen receptor α (ERα), and most patients with ERα-positive breast cancer benefit from antiestrogen therapy. The ERα-modulator tamoxifen and ERα-downregulator fulvestrant are commonly employed antiestrogens. Antiestrogen resistance remains a clinical...... of HIF2α in MCF-7 cells significantly decreased sensitivity to antiestrogens, further implicating HIF2α in antiestrogen resistance. EGFR is known to contribute to antiestrogen resistance: we further show that HIF2α drives hypoxic induction of EGFR and that EGFR induces HIF2α expression. Downregulation...

  19. Protein tyrosine phosphatase SHP-1 sensitizes EGFR/HER-2 positive breast cancer cells to trastuzumab through modulating phosphorylation of EGFR and HER-2

    Directory of Open Access Journals (Sweden)

    Wu YF

    2015-09-01

    on tumorigenicity and trastuzumab sensitivity were confirmed via in vivo xenograft model.Results: Trastuzumab-resistant SKBr-3 cells showed aberrant co-expression of EGFR and HER-2. Introduction of wild-type SHP-1 inhibited cell proliferation, clone formation, and promoted the apoptosis induced by trastuzumab. Meanwhile, SHP-1 overexpression reduced phosphorylation levels of EGFR and HER-2 both in parental and trastuzumab-resistant SKBr-3 cells. In vivo study showed an increased antitumor effect of trastuzumab in SHP-1 overexpressed xenografts. At last, we discovered that SHP-1 can make complexes with both EGFR and HER-2, and both phospho-EGFR and phosphor-HER-2 levels in wild-type SHP-1 immunoprecipitates were less than those in phosphatase-inactive SHP-1 (C453S immunoprecipitates, indicating that EGFR and HER-2 are potential substrates of SHP-1.Conclusion: Taken together, we have demonstrated that the SHP-1 is a negative regulatory factor of the tyrosine kinase activity of HER-2 and EGFR through inhibiting phosphorylation. Dual targeting of EGFR and HER-2, by combining trastuzumab with SHP-1 overexpression, may improve response in HER-2 overexpressing breast cancer cells that also express high levels of EGFR. Keywords: breast cancer, trastuzumab, EGFR, HER-2, SHP-1, drug resistance 

  20. G protein-coupled receptor 30 mediates estrogen-induced proliferation of primordial germ cells via EGFR/Akt/β-catenin signaling pathway.

    Science.gov (United States)

    Ge, Chutian; Yu, Minli; Zhang, Caiqiao

    2012-07-01

    In vertebrates, estrogens are required for the normal development and function of postnatal gonads. However, it remains unclear whether estrogens are able to modulate development of the fetal germ cells. Here, we show that, unexpectedly, chicken primordial germ cells (PGC) lacking estrogen receptor α/β still proliferate in response to 17β-estradiol (E(2)). This is due to the capacity of G protein-coupled receptor 30 (GPR30), existing on PGC, to directly bind E(2). Knockdown experiments suggest that GPR30 is required for E(2)-stimulated PGC proliferation. Furthermore, this estrogen-induced activation of GPR30 is revealed to occur through the Gβγ-subunit protein-dependent and through the matrix metalloproteinase-dependent transactivation of the epidermal growth factor receptor. Epidermal growth factor receptor activation results in a series of intracellular events, including activation of the phosphatidylinositol 3-kinase/serine-threonine kinase/β-catenin pathway, which are followed by the induction of c-fos, c-myc, cyclin D1/E, and B-cell lymphoma 2 expression, and the inhibition of B-cell lymphoma 2-associated X protein expression and caspase3/9 activity. This eventually leads to decreased apoptosis and increased PGC proliferation. Collectively, these findings offer novel insights into the dynamic mechanism of estrogen action on PGC proliferation and suggest that E(2)/GPR30 signaling might play an important role in regulating fetal germ cell development, particularly at the stage before sexual differentiation. PMID:22635679

  1. Effect of ethanolic extract of leaves of Paederia foetida Linn. on acetic acid induced colitis in albino rats

    Directory of Open Access Journals (Sweden)

    Swarnamoni Das

    2013-01-01

    Conclusions: The ethanolic extract of leaves of P. foetida showed significant amelioration of experimentally induced colitis, which may be attributed to its anti-inflammatory and antioxidant property.

  2. Influenza A induces the major secreted airway mucin MUC5AC in a protease-EGFR-extracellular regulated kinase-Sp1-dependent pathway.

    Science.gov (United States)

    Barbier, Diane; Garcia-Verdugo, Ignacio; Pothlichet, Julien; Khazen, Roxana; Descamps, Delphyne; Rousseau, Karine; Thornton, David; Si-Tahar, Mustapha; Touqui, Lhousseine; Chignard, Michel; Sallenave, Jean-Michel

    2012-08-01

    Mucins, the main glycoproteins present within mucus, modulate the rheologic properties of airways and participate in lung defense. They are thought to be able to trap and eliminate microorganisms from the lung. Among the mucins secreted in the lung, MUC5AC is the most prominent factor secreted by surface epithelial cells. Although much is known about the signaling pathways involved in the regulation of MUC5AC by host factors such as cytokines or proteases, less is known about the pathways triggered by microorganisms and, specifically, by influenza A virus (IAV). We therefore set up experiments to dissect the molecular mechanisms responsible for the potential modulation of MUC5AC by IAV. Using epithelial cells, C57/Bl6 mice, and IAV strains, we measured MUC5AC expression at the RNA and protein levels, specificity protein 1 (Sp1) activation, and protease activity. Intermediate molecular partners were confirmed using pharmacological inhibitors, blocking antibodies, and small interfering (si)RNAs. We showed in vitro and in vivo that IAV up-regulates epithelial cell-derived MUC5AC and Muc5ac expression in mice, both at transcriptional (through the induction of Sp1) and translational levels. In addition, we determined that this induction was dependent on a protease-epithelial growth factor receptor-extracellular regulated kinase-Sp1 signaling cascade, involving in particular the human airway trypsin. Our data point to MUC5AC as a potential modulatory mechanism by which the lung epithelia respond to IAV infection, and we dissect, for the first time to the best of our knowledge, the molecular partners involved. Future experiments using MUC5AC-targeted strategies should help further unravel the pathophysiological consequences of IAV-induced MUC5AC expression for lung homeostasis. PMID:22383584

  3. 5-Episinuleptolide Acetate, a Norcembranoidal Diterpene from the Formosan Soft Coral Sinularia sp., Induces Leukemia Cell Apoptosis through Hsp90 Inhibition

    Directory of Open Access Journals (Sweden)

    Yao-Tsung Yeh

    2013-03-01

    Full Text Available 5-Episinuleptolide acetate (5EPA, a cytotoxic norcembranoidal diterpene recently identified from the Formosan soft coral Sinularia sp., exhibited potent activity against the K562, Molt 4 and HL 60 cancer cell lines. The antiproliferative assay, as well as the annexin V-FITC/propidium iodide (PI apoptotic assay, indicated that the HL 60 cell line is the most sensitive one towards 5EPA. This diterpenoid led to caspases -3, -8, and -9 activation as well as PARP cleavage. It also induced ROS generation, calcium accumulation and disruption of mitochondrial membrane potential. Additionally, the expression levels of Hsp90 protein and several client proteins were downregulated in response to 5EPA treatment. These results suggest that 5EPA’s cytotoxic effect on HL 60 cells may be attributed to the inhibition of Hsp90 as well as the induction of mitochondrial stress which finally results in apoptotic cell death.

  4. Conversion from the "oncogene addiction" to "drug addiction" by intensive inhibition of the EGFR and MET in lung cancer with activating EGFR mutation.

    Science.gov (United States)

    Suda, Kenichi; Tomizawa, Kenji; Osada, Hirotaka; Maehara, Yoshihiko; Yatabe, Yasushi; Sekido, Yoshitaka; Mitsudomi, Tetsuya

    2012-06-01

    Emergence of acquired resistance is virtually inevitable in patients with a mutation in the epidermal growth factor receptor gene (EGFR) treated with EGFR tyrosine kinase inhibitors (TKIs). Several novel TKIs that may prevent or overcome the resistance mechanisms are now under clinical development. However, it is unknown how tumor cells will respond to intensive treatment using these novel TKIs. We previously established HCC827EPR cells, which are T790M positive, through combined treatment with erlotinib and a MET-TKI from erlotinib-hypersensitive HCC827 cells. In this study, we treated HCC827EPR cells sequentially with an irreversible EGFR-TKI, CL-387,785, to establish resistant cells (HCC827CLR), and we analyzed the mechanisms responsible for resistance. In HCC827CLR cells, PTEN expression was downregulated and Akt phosphorylation persisted in the presence of CL-387,785. Akt inhibition restored CL-387,785 sensitivity. In addition, withdrawal of CL-387,785 reduced cell viability in HCC827CLR cells, indicating that these cells were "addicted" to CL-387,785. HCC827CLR cells overexpressed the EGFR, and inhibition of the EGFR or MEK-ERK was needed to maintain cell proliferation. Increased senescence was observed in HCC827CLR cells in the drug-free condition. Through long-term culture of HCC827CLR cells without CL-387,785, we established HCC827-CL-387,785-independent cells, which exhibited decreased EGFR expression and a mesenchymal phenotype. In conclusion, PTEN downregulation is a newly identified mechanism underlying the acquired resistance to irreversible EGFR-TKIs after acquisition of T790M against erlotinib. This series of experiments highlights the flexibility of cancer cells that have adapted to environmental stresses induced by intensive treatment with TKIs. PMID:22133747

  5. Fluctuations in eGFR in relation to unenhanced and enhanced MRI and CT outpatients

    DEFF Research Database (Denmark)

    Azzouz, Manal; Rømsing, Janne; Thomsen, Henrik S

    2014-01-01

    OBJECTIVE: To study fluctuations in estimated glomerular filtration rate (eGFR) in relation to contrast medium (CM) enhanced magnetic resonance imaging (MRI) and computed tomography (CT) compared to control groups in outpatients. MATERIALS AND METHODS: eGFR was determined right before the imaging...... relevant rise in eGFR after three days in all four groups. The average eGFR variation was 4.8ml/min/1.73m(2). There were large variations in eGFR between the two measurements in 45.8% of the patients as they had a change greater than ±10ml/min/1.73m(2). Only three patients fulfilled the contrast......-induced nephropathy (CIN) requirement when the definition s-creatinine ≥44μmol/l (0.5mg/dl) was used. CONCLUSIONS: eGFR in outpatients undergoing MRI or CT did vary independently of whether the patient received contrast or not. The findings probably reflect the natural variations in s-creatinine levels. This should...

  6. Fluctuations in eGFR in relation to unenhanced and enhanced MRI and CT outpatients

    Energy Technology Data Exchange (ETDEWEB)

    Azzouz, Manal, E-mail: manalazzouz@gmail.com [Department of Diagnostic Radiology, Copenhagen University Hospital Herlev, Herlev Ringvej 75, DK 2730 Herlev (Denmark); Rømsing, Janne [Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, DK-2100 Copenhagen Ø (Denmark); Thomsen, Henrik S. [Department of Diagnostic Radiology, Copenhagen University Hospital Herlev, Herlev Ringvej 75, DK 2730 Herlev (Denmark)

    2014-06-15

    Objective: To study fluctuations in estimated glomerular filtration rate (eGFR) in relation to contrast medium (CM) enhanced magnetic resonance imaging (MRI) and computed tomography (CT) compared to control groups in outpatients. Materials and methods: eGFR was determined right before the imaging procedure and three days later at the department or at the patient's home. The iodine-based and gadolinium-based contrast media were the same as used for all other examinations at the department. Results: A total of 716 patients completed the study. There was a statistically significant, but not clinically relevant rise in eGFR after three days in all four groups. The average eGFR variation was 4.8 ml/min/1.73 m{sup 2}. There were large variations in eGFR between the two measurements in 45.8% of the patients as they had a change greater than ±10 ml/min/1.73 m{sup 2}. Only three patients fulfilled the contrast-induced nephropathy (CIN) requirement when the definition s-creatinine ≥44 μmol/l (0.5 mg/dl) was used. Conclusions: eGFR in outpatients undergoing MRI or CT did vary independently of whether the patient received contrast or not. The findings probably reflect the natural variations in s-creatinine levels. This should be taken into consideration when CIN is studied.

  7. Cognitive enhancing and antioxidant activity of ethyl acetate soluble fraction of the methanol extract of Hibiscus rosa sinensis in scopolamine-induced amnesia

    Directory of Open Access Journals (Sweden)

    Vandana S Nade

    2011-01-01

    Full Text Available Objective : The objective of the present study was to evaluate the cognitive enhancing and antioxidant activity of Hibiscus rosa sinensis. Materials and Methods : The learning and memory was impaired by administration of scopolamine (1 mg/kg, i.p. in mice which is associated with altered brain oxidative status. The object recognition test (ORT and passive avoidance test (PAT were used to assess cognitive enhancing activity. Animals were treated with an ethyl acetate soluble fraction of the methanol extract of H. sinensis (25, 50 and 100 mg/kg, p.o. Results : The ethyl acetate soluble fraction of the methanol extract of H. sinensis (EASF attenuated amnesia induced by scopolamine and aging. The discrimination index (DI was significantly decreased in the aged and scopolamine group in ORT. Pretreatment with EASF significantly increased the DI. In PAT, scopolamine-treated mice exhibited significantly shorter step-down latencies (SDL. EASF treatment showed a significant increase in SDL in young, aged as well as in scopolamine-treated animals. The biochemical analysis of brain revealed that scopolamine treatment increased lipid peroxidation and decreased levels of superoxide dismutase (SOD and glutathione reductase (GSH. Administration of extract significantly reduced LPO and reversed the decrease in brain SOD and GSH levels. The administration of H. sinensis improved memory in amnesic mice and prevented the oxidative stress associated with scopolamine. The mechanism of such protection of H. sinensis may be due to augmentation of cellular antioxidants. Conclusion : The results of the present study suggested that H. sinensis had a protective role against age and scopolamine-induced amnesia, indicating its utility in management of cognitive disorders.

  8. Simultaneous Inhibition of EGFR and PI3K Enhances Radiosensitivity in Human Breast Cancer

    International Nuclear Information System (INIS)

    Purpose: Mutations in the epidermal growth factor receptor (EGFR)/phosphoinositide 3-kinase (PI3K)/Akt signaling transduction pathway are common in cancer. This pathway is imperative to the radiosensitivity of cancer cells. We aimed to investigate the radiosensitizing effects of the simultaneous inhibition of EGFR and PI3K in breast cancer cells. Methods and Materials: MCF-7 cell lines with low expression of EGFR and wild-type PTEN and MDA-MB-468 cell lines with high expression of EGFR and mutant PTEN were used. The radiosensitizing effects by the inhibition of EGFR with AG1478 and/or PI3K with Ly294002 were determined by colony formation assay, Western blot was used to investigate the effects on downstream signaling. Flow cytometry was used for apoptosis and cell cycle analysis. Mice-bearing xenografts of MDA-MB-468 breast cancer cells were also used to observe the radiosensitizing effect. Results: Simultaneous inhibition of EGFR and PI3K greatly enhanced radiosensitizing effect in MDA-MB-468 in terms of apoptosis and mitotic death, either inhibition of EGFR or PI3K alone could enhance radiosensitivity with a dose-modifying factor (DMFSF2) of 1.311 and 1.437, radiosensitizing effect was further enhanced by simultaneous inhibition of EGFR and PI3K with a DMFSF2 at 2.698. DNA flow cytometric analysis indicated that dual inhibition combined with irradiation significantly induced G0/G1 phase arrest in MDA-MB-468 cells. The expression of phosphor-Akt and phosphor-Erk1/2 (induced by irradiation and PI3K inhibitor) were fully attenuated by simultaneous treatment with both inhibitors in combination with irradiation. In addition, dual inhibition combined with irradiation induced dramatic tumor growth delay in MDA-MB-468 xenografts. Conclusions: Our study indicated that simultaneous inhibition of EGFR and PI3K could further sensitize the cancer cells to irradiation compared to the single inhibitor with irradiation in vitro and in vivo. The approach may have important

  9. Simultaneous Inhibition of EGFR and PI3K Enhances Radiosensitivity in Human Breast Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Li Ping; Zhang Qing [Department of Radiation Oncology, 6th People' s Hospital of Jiao Tong University, Shanghai 200233 (China); Torossian, Artour [Vanderbilt University, School of Medicine, Nashville, TN (United States); Li Zhaobin; Xu Wencai [Department of Radiation Oncology, 6th People' s Hospital of Jiao Tong University, Shanghai 200233 (China); Lu Bo [Department of Radiation Oncology, Thomas Jefferson University and Hospitals, Inc. Philadelphia, PA (United States); Fu Shen, E-mail: fushen1117@gmail.com [Department of Radiation Oncology, 6th People' s Hospital of Jiao Tong University, Shanghai 200233 (China)

    2012-07-01

    Purpose: Mutations in the epidermal growth factor receptor (EGFR)/phosphoinositide 3-kinase (PI3K)/Akt signaling transduction pathway are common in cancer. This pathway is imperative to the radiosensitivity of cancer cells. We aimed to investigate the radiosensitizing effects of the simultaneous inhibition of EGFR and PI3K in breast cancer cells. Methods and Materials: MCF-7 cell lines with low expression of EGFR and wild-type PTEN and MDA-MB-468 cell lines with high expression of EGFR and mutant PTEN were used. The radiosensitizing effects by the inhibition of EGFR with AG1478 and/or PI3K with Ly294002 were determined by colony formation assay, Western blot was used to investigate the effects on downstream signaling. Flow cytometry was used for apoptosis and cell cycle analysis. Mice-bearing xenografts of MDA-MB-468 breast cancer cells were also used to observe the radiosensitizing effect. Results: Simultaneous inhibition of EGFR and PI3K greatly enhanced radiosensitizing effect in MDA-MB-468 in terms of apoptosis and mitotic death, either inhibition of EGFR or PI3K alone could enhance radiosensitivity with a dose-modifying factor (DMF{sub SF2}) of 1.311 and 1.437, radiosensitizing effect was further enhanced by simultaneous inhibition of EGFR and PI3K with a DMF{sub SF2} at 2.698. DNA flow cytometric analysis indicated that dual inhibition combined with irradiation significantly induced G0/G1 phase arrest in MDA-MB-468 cells. The expression of phosphor-Akt and phosphor-Erk1/2 (induced by irradiation and PI3K inhibitor) were fully attenuated by simultaneous treatment with both inhibitors in combination with irradiation. In addition, dual inhibition combined with irradiation induced dramatic tumor growth delay in MDA-MB-468 xenografts. Conclusions: Our study indicated that simultaneous inhibition of EGFR and PI3K could further sensitize the cancer cells to irradiation compared to the single inhibitor with irradiation in vitro and in vivo. The approach may have

  10. Medroxyprogesterone acetate alters Mycobacterium bovis BCG-induced cytokine production in peripheral blood mononuclear cells of contraceptive users.

    Directory of Open Access Journals (Sweden)

    Léanie Kleynhans

    Full Text Available Most individuals latently infected with Mycobacterium tuberculosis (M.tb contain the infection by a balance of effector and regulatory immune responses. This balance can be influenced by steroid hormones such as glucocorticoids. The widely used contraceptive medroxyprogesterone acetate (MPA possesses glucocorticoid activity. We investigated the effect of this hormone on immune responses to BCG in household contacts of active TB patients. Multiplex bead array analysis revealed that MPA demonstrated both glucocorticoid and progestogenic properties at saturating and pharmacological concentrations in peripheral blood mononuclear cells (PBMCs and suppressed antigen specific cytokine production. Furthermore we showed that PBMCs from women using MPA produced significantly lower levels of IL-1α, IL-12p40, IL-10, IL-13 and G-CSF in response to BCG which corresponded with lower numbers of circulating monocytes observed in these women. Our research study is the first to show that MPA impacts on infections outside the genital tract due to a systemic effect on immune function. Therefore MPA use could alter susceptibility to TB, TB disease severity as well as change the efficacy of new BCG-based vaccines, especially prime-boost vaccine strategies which may be administered to adult or adolescent women in the future.

  11. Gravity induced, asymmetric unloading of indole-3-acetic acid from the stele of Zea mays into the mesocotyl cortex

    International Nuclear Information System (INIS)

    Previous studies from this laboratory have demonstrated an increase within 3 min in both free and ester indole-3-acetic acid (IAA) on the lower side of the mesocotyl cortex of a gravity stimulated Zea mays seedling. Since both free and ester IAA are being transported from endosperm to shoot through the stele these results suggest that the gravity stimulus affects movement of IAA and/or its esters from stele to cortex. To test this postulate they injected 5-(3H)-IAA into the endosperm and, after a 30 min period with the plants held vertically, severed the kernel from the shoot and placed the plants in a horizontal position. After 60 min the distribution of radioactivity in the mesocotyl cortex was 55 + 3% in the lower half and 45 + 3% in the upper half. These results support the working theory that a target for the gravity stimulus is the gating mechanism for the movement of hormone from stele to cortex

  12. EGFR CA repeat polymorphism predict clinical outcome in EGFR mutation positive NSCLC patients treated with erlotinib

    DEFF Research Database (Denmark)

    Winther Larsen, Anne; Nissen, Peter Henrik; Meldgaard, Peter;

    2014-01-01

    OBJECTIVES: Somatic mutations in the epidermal growth factor receptor (EGFR) are predictors of efficacy for treatment with the EGFR tyrosine kinase inhibitor erlotinib in non-small cell lung cancer (NSCLC). A CA repeat polymorphism in intron 1 of the EGFR gene influences the transcription...... of the EGFR gene. This study evaluates the association between the CA repeat polymorphism and outcome in NSCLC patients treated with erlotinib.MATERIALS AND METHODS: Number of CA repeats in the EGFR gene was evaluated with PCR-fragment length analysis by capillary electrophoresis in 432 advanced NSCLC...... patients treated with erlotinib irrespective of EGFR mutation status. Patients were dichotomized into harboring short allele (CA≤16 in any allele) or long alleles (CA>16 in both alleles). Number of repeats was correlated with clinical characteristic and outcome. A subgroup analysis was performed based...

  13. Radioresistance of human glioma spheroids and expression of HSP70, p53 and EGFr

    Directory of Open Access Journals (Sweden)

    Fedrigo Carlos A

    2011-11-01

    Full Text Available Abstract Background Radiation therapy is routinely prescribed for high-grade malignant gliomas. However, the efficacy of this therapeutic modality is often limited by the occurrence of radioresistance, reflected as a diminished susceptibility of the irradiated cells to undergo cell death. Thus, cells have evolved an elegant system in response to ionizing radiation induced DNA damage, where p53, Hsp70 and/or EGFr may play an important role in the process. In the present study, we investigated whether the content of p53, Hsp70 and EGFr are associated to glioblastoma (GBM cell radioresistance. Methods Spheroids from U-87MG and MO59J cell lines as well as spheroids derived from primary culture of tumor tissue of one GBM patient (UGBM1 were irradiated (5, 10 and 20 Gy, their relative radioresistance were established and the p53, Hsp70 and EGFr contents were immunohistochemically determined. Moreover, we investigated whether EGFr-phospho-Akt and EGFr-MEK-ERK pathways can induce GBM radioresistance using inhibitors of activation of ERK (PD098059 and Akt (wortmannin. Results At 5 Gy irradiation UGBM1 and U-87MG spheroids showed growth inhibition whereas the MO59J spheroid was relatively radioresistant. Overall, no significant changes in p53 and Hsp70 expression were found following 5 Gy irradiation treatment in all spheroids studied. The only difference observed in Hsp70 content was the periphery distribution in MO59J spheroids. However, 5 Gy treatment induced a significant increase on the EGFr levels in MO59J spheroids. Furthermore, treatment with inhibitors of activation of ERK (PD098059 and Akt (wortmannin leads to radiosensitization of MO59J spheroids. Conclusions These results indicate that the PI3K-Akt and MEK-ERK pathways triggered by EGFr confer GBM radioresistance.

  14. Decreased autocrine EGFR signaling in metastatic breast cancer cells inhibits tumor growth in bone and mammary fat pad.

    Science.gov (United States)

    Nickerson, Nicole K; Mohammad, Khalid S; Gilmore, Jennifer L; Crismore, Erin; Bruzzaniti, Angela; Guise, Theresa A; Foley, John

    2012-01-01

    Breast cancer metastasis to bone triggers a vicious cycle of tumor growth linked to osteolysis. Breast cancer cells and osteoblasts express the epidermal growth factor receptor (EGFR) and produce ErbB family ligands, suggesting participation of these growth factors in autocrine and paracrine signaling within the bone microenvironment. EGFR ligand expression was profiled in the bone metastatic MDA-MB-231 cells (MDA-231), and agonist-induced signaling was examined in both breast cancer and osteoblast-like cells. Both paracrine and autocrine EGFR signaling were inhibited with a neutralizing amphiregulin antibody, PAR34, whereas shRNA to the EGFR was used to specifically block autocrine signaling in MDA-231 cells. The impact of these was evaluated with proliferation, migration and gene expression assays. Breast cancer metastasis to bone was modeled in female athymic nude mice with intratibial inoculation of MDA-231 cells, and cancer cell-bone marrow co-cultures. EGFR knockdown, but not PAR34 treatment, decreased osteoclasts formed in vitro (p<0.01), reduced osteolytic lesion tumor volume (p<0.01), increased survivorship in vivo (p<0.001), and resulted in decreased MDA-231 growth in the fat pad (p<0.01). Fat pad shEGFR-MDA-231 tumors produced in nude mice had increased necrotic areas and decreased CD31-positive vasculature. shEGFR-MDA-231 cells also produced decreased levels of the proangiogenic molecules macrophage colony stimulating factor-1 (MCSF-1) and matrix metalloproteinase 9 (MMP9), both of which were decreased by EGFR inhibitors in a panel of EGFR-positive breast cancer cells. Thus, inhibiting autocrine EGFR signaling in breast cancer cells may provide a means for reducing paracrine factor production that facilitates microenvironment support in the bone and mammary gland. PMID:22276166

  15. Decreased autocrine EGFR signaling in metastatic breast cancer cells inhibits tumor growth in bone and mammary fat pad.

    Directory of Open Access Journals (Sweden)

    Nicole K Nickerson

    Full Text Available Breast cancer metastasis to bone triggers a vicious cycle of tumor growth linked to osteolysis. Breast cancer cells and osteoblasts express the epidermal growth factor receptor (EGFR and produce ErbB family ligands, suggesting participation of these growth factors in autocrine and paracrine signaling within the bone microenvironment. EGFR ligand expression was profiled in the bone metastatic MDA-MB-231 cells (MDA-231, and agonist-induced signaling was examined in both breast cancer and osteoblast-like cells. Both paracrine and autocrine EGFR signaling were inhibited with a neutralizing amphiregulin antibody, PAR34, whereas shRNA to the EGFR was used to specifically block autocrine signaling in MDA-231 cells. The impact of these was evaluated with proliferation, migration and gene expression assays. Breast cancer metastasis to bone was modeled in female athymic nude mice with intratibial inoculation of MDA-231 cells, and cancer cell-bone marrow co-cultures. EGFR knockdown, but not PAR34 treatment, decreased osteoclasts formed in vitro (p<0.01, reduced osteolytic lesion tumor volume (p<0.01, increased survivorship in vivo (p<0.001, and resulted in decreased MDA-231 growth in the fat pad (p<0.01. Fat pad shEGFR-MDA-231 tumors produced in nude mice had increased necrotic areas and decreased CD31-positive vasculature. shEGFR-MDA-231 cells also produced decreased levels of the proangiogenic molecules macrophage colony stimulating factor-1 (MCSF-1 and matrix metalloproteinase 9 (MMP9, both of which were decreased by EGFR inhibitors in a panel of EGFR-positive breast cancer cells. Thus, inhibiting autocrine EGFR signaling in breast cancer cells may provide a means for reducing paracrine factor production that facilitates microenvironment support in the bone and mammary gland.

  16. Preventive effect of a pectic polysaccharide of the common cranberry Vaccinium oxycoccos L. on acetic acid-induced colitis in mice

    Institute of Scientific and Technical Information of China (English)

    Sergey V Popov; Pavel A Markov; Ida R Nikitina; Sergey Petrishev; Vasily Smirnov; Yury S Ovodov

    2006-01-01

    AIM: To study isolation and chemical characterization of pectin derived from the common cranberry Vaccinium oxycoccos L. (oxycoccusan OP) and the testing of its preventive effect on experimental colitis.METHODS: Mice were administrated orally with OP two days prior to a rectal injection of 5% acetic acid and examined for colonic damage 24 h later. Colonic inflammation was characterized by macroscopical injury and enhanced levels of myeloperoxidase activity measured spectrophotometrically with o-phenylene diamine as the substrate. The mucus contents of the colon were determined by the Alcian blue dye binding method. Vascular permeability was estimated using 4%Evans blue passage after i.p. injection of 0.05 mol/L acetic acid.RESULTS: In the mice treated with OP, colonic macroscopic scores (1.1 ± 0.4 vs 2.7, P < 0.01) and the total square area of damage (10 ± 2 vs 21 ± 7, P < 0.01)were significantly reduced when compared with the vehicle-treated colitis group. OP was shown to decrease the tissue myeloperoxidase activity in colons (42 ± 11 vs 112 ± 40, P < 0.01) and enhance the amount of mucus of colitis mice (0.9 ± 0.1 vs 0.4 ± 0.1, P < 0.01). The level of colonic malondialdehyde was noted to decrease in OP-pretreated mice (3.6 ± 0.7 vs 5.1 ± 0.8, P < 0.01).OP was found to decrease the inflammatory status of mice as was determined by reduction of vascular permeability (161 ± 34 vs 241 ± 21, P < 0.01). Adhesion of peritoneal neutrophils and macrophages was also shown to decrease after administration of OP (141 ± 50vs 235 ± 37, P < 0.05).CONCLUSION: Thus, a preventive effect of pectin from the common cranberry, namely oxycoccusan OP,on acetic acid-induced colitis in mice was detected.A reduction of neutrophil infiltration and antioxidant action may be implicated in the protective effect of oxycoccusan.

  17. EGFR is dispensable for c-Met-mediated proliferation and survival activities in mouse adult liver oval cells.

    Science.gov (United States)

    Martínez-Palacián, A; del Castillo, G; Herrera, B; Fernández, M; Roncero, C; Fabregat, I; Sánchez, A

    2012-02-01

    Liver progenitor cells rise as potential critical players in hepatic regeneration but also carcinogenesis. It is therefore mandatory to define the signals controlling their activation and expansion. Recently, by using a novel in vitro model of oval cell lines expressing a mutant tyrosine kinase-inactive form of c-Met we demonstrated that autocrine c-Met signalling plays an essential role in promoting oval cell survival. Here, we investigated the significance of the epidermal growth factor receptor (EGFR) signalling in oval cell proliferation and survival, as well as a potential functional crosstalk between the c-Met and the EGFR pathways. We found an autocrine activation of the EGFR-triggered pathway in Met(flx/flx) and Met(-/-) oval cells as judged by constitutive expression of the EGFR ligands, transforming growth factor-alpha (TGF-α) and heparin-binding EGF like growth factor (HB-EGF), and activation of EGFR. On the other hand, treatment with AG1478, a specific inhibitor of EGFR, effectively blocked endogenous and EGF-induced proliferation, while increased serum withdrawal and transforming growth factor-beta (TGF-β)-induced apoptosis. These results suggest that constitutively activated EGFR might promote oval cell proliferation and survival. We found that hepatocyte growth factor (HGF) does not transactivate EGFR nor EGF transactivates c-Met. Furthermore, treatment with AG1478 or EGFR gene silencing did not interfere with HGF-mediated activation of target signals, such as protein kinase B (AKT/PKB), and extracellular signal-regulated kinases 1/2 (ERK 1/2), nor did it have any effect on HGF-induced proliferative and antiapoptotic activities in Met(flx/flx) cells, showing that HGF does not require EGFR activation to mediate such responses. EGF induced proliferation and survival equally in Met(flx/flx) and Met(-/-) oval cells, proving that EGFR signalling does not depend on c-Met tyrosine kinase activity. Together, our results provide strong evidence that in

  18. Blockade of sonic hedgehog signal pathway enhances antiproliferative effect of EGFR inhibitor in pancreatic cancer cells

    Institute of Scientific and Technical Information of China (English)

    Wei-guo HU; Tao LIU; Jiong-xin XIONG; Chun-you WANG

    2007-01-01

    Aim: To investigate the expression of sonic hedgehog (SHH) and epidermal growth factor receptor (EGFR) signal molecules in pancreatic cancer cells, and to assess the inhibitory effects through the blockade of the SHH and EGFR signaling path- ways by cyclopamine and Iressa, respectively. Methods: The expression of SHH and EGFR in pancreatic cancer cell lines (PANC-1, SUIT-2, and ASPC-1) was de-tected by RT-PCR and Western blot analysis. After treatment with different con-centrations of cyclopamine, alone or in combination with Iressa, the antiproliferative effect on pancreatic cancer cells was analyzed by methyl thiazolyl tetrazolium assays. A flow cytometry analysis was used to detect the cellular cycle distribu-tion and apoptosis of pancreatic cancer cells. Results: All of the 3 pancreatic cancer cell lines expressed SHH, Smoothened (SMO), and EGFR. Cyclopamine could downregulate the expression of EGFR in all cell lines. Cyclopamine or Iressa could induce a growth inhibitory effect in a dose-dependent manner. Moreover,the combined use of 2.5 μmol/L cyclopamine and 1 μmol/L Iressa induced an enhanced inhibitory effect and a greater apoptosis rate than any agent alone. The percentage of the cell population of the G0/G1 and sub-G1 phases was significantly increased along with the increasing dose of cyclopamine and/or Iressa. Conclusion: The blockade of the sonic hedgehog signal pathway enhances the antiproliferative effect of the EGFR inhibitor through the downregulation of its expression in pancreatic cancer cells. The simultaneous blockade of SHH and EGFR signaling represents possible targets of new treatment strategies for pan-creatic carcinoma.

  19. Failure of a single dose of medroxyprogesterone acetate to induce uterine infertility in postnatally treated domestic cats.

    Science.gov (United States)

    Lopez Merlo, M; Faya, M; Blanco, P G; Carransa, A; Barbeito, C; Gobello, C

    2016-03-01

    In mice and sheep, neonatal administration of progesterone or progestins inhibited development of uterine glands. The aims of the present study were (1) to describe uterine gland development on postnatal Days 6 to 8 and (2) to evaluate the effects of a single postnatal administration of a progestin on reproduction and adult uterine glands morphology and function in domestic cats. Necropsy was performed on three 1-week-old female cats which had died unrelated to this study. Ten female kittens were randomly assigned within the first 24 hours of birth to: medroxyprogesterone acetate 10 mg/animal subcutaneously (MPA; n = 6) or placebo (PLC; n = 4) and followed up until puberty when they were mated. Twenty-four days after the end of estrus, ovulation and pregnancy were diagnosed by serum progesterone measurement and ultrasonography, respectively. Then, all the cats were ovariohysterectomized. After necropsy or surgery, the excised organs were histologically evaluated. Seven queens ovulated (4 of 6 MPA and 3 of 4 PLC; P > 0.1) and were pregnant (P > 0.1). Four MPA cats presented endometrial hyperplasia and one of them developed a pyometra. The 1-week-old females presented uterine glands in the stage of budding and incipient penetration of the glandular epithelium into the underlying stroma. The MPA-treated queens revealed that the area occupied by uterine glands per square-micrometer (0.55 ± 0.2 vs. 0.49 ± 0.2; P > 0.1) and the height of the glandular epithelium (μm; 24.5 ± 6.7 vs. 24.4 ± 7.2; P > 0.1) did not differ from those of the PLC group. Neither significant gross nor microscopical differences were also found for ovaries (P > 0.1). It is concluded that 1-week-old kittens had an incipient stage of uterine gland development and that a single postnatal supraphysiological dose of MPA did not alter uterine adenogenesis in this species. Furthermore, this treatment seemed to predispose to uterine disease without prevention of fertility. PMID:26534826

  20. Exogenous Restoration of TUSC2 Expression Induces Responsiveness to Erlotinib in Wildtype Epidermal Growth Factor Receptor (EGFR Lung Cancer Cells through Context Specific Pathways Resulting in Enhanced Therapeutic Efficacy.

    Directory of Open Access Journals (Sweden)

    Bingbing Dai

    Full Text Available Expression of the tumor suppressor gene TUSC2 is reduced or absent in most lung cancers and is associated with worse overall survival. In this study, we restored TUSC2 gene expression in several wild type EGFR non-small cell lung cancer (NSCLC cell lines resistant to the epidermal growth factor receptor (EGFR tyrosine kinase inhibitor erlotinib and analyzed their sensitivity to erlotinib in vitro and in vivo. A significant inhibition of cell growth and colony formation was observed with TUSC2 transient and stable expression. TUSC2-erlotinib cooperativity in vitro could be reproduced in vivo in subcutaneous tumor growth and lung metastasis formation lung cancer xenograft mouse models. Combination treatment with intravenous TUSC2 nanovesicles and erlotinib synergistically inhibited tumor growth and metastasis, and increased apoptotic activity. High-throughput qRT-PCR array analysis enabling multi-parallel expression profile analysis of eighty six receptor and non-receptor tyrosine kinase genes revealed a significant decrease of FGFR2 expression level, suggesting a potential role of FGFR2 in TUSC2-enhanced sensitivity to erlotinib. Western blots showed inhibition of FGFR2 by TUSC2 transient transfection, and marked increase of PARP, an apoptotic marker, cleavage level after TUSC2-erlotinb combined treatment. Suppression of FGFR2 by AZD4547 or gene knockdown enhanced sensitivity to erlotinib in some but not all tested cell lines. TUSC2 inhibits mTOR activation and the latter cell lines were responsive to the mTOR inhibitor rapamycin combined with erlotinib. These results suggest that TUSC2 restoration in wild type EGFR NSCLC may overcome erlotinib resistance, and identify FGFR2 and mTOR as critical regulators of this activity in varying cellular contexts. The therapeutic activity of TUSC2 could extend the use of erlotinib to lung cancer patients with wildtype EGFR.

  1. Intratumoral distribution of EGFR-amplified and EGFR-mutated cells in pulmonary adenocarcinoma.

    Science.gov (United States)

    Soma, Shingo; Tsuta, Koji; Takano, Toshimi; Hatanaka, Yutaka; Yoshida, Akihiko; Suzuki, Kenji; Asamura, Hisao; Tsuda, Hitoshi

    2014-03-01

    Alterations in the epidermal growth factor receptor (EGFR) gene are associated with carcinogenesis in non-small cell lung cancer. However, the intratumoral distribution of these abnormalities has not been elucidated. This study included patients with surgically resected lung adenocarcinoma. The predominant histological growth pattern was determined. Chromogenic in situ hybridization (CISH) and EGFR-mutation specific-antibodies were used for analysis of changes in gene copy number and EGFR mutations, respectively. EGFR mutation detected immunohistochemistry (IHC) and amplification were identified in 31 (53%) and 30 (52%) cases, respectively. The predominant growth patterns in the 58 tumors evaluated were papillary (28, 48%), lepidic (8, 14%), acinar (15, 26%), and solid (7, 12%). EGFR mutations were the least common in cases with a solid predominant pattern. The incidence of EGFR amplification did not differ among predominant patterns. Analyzing each histological subtype, no differences were noted between the prevalence of EGFR-IHC positive and CISH-positive rates. In the analysis of EGFR amplification, CISH-positive status was more prevalent in IHC-positive cases than in IHC-negative cases. All 19 cases that were both IHC and CISH positive were analyzed. In 17 cases (90%), the IHC-positive area was equal to or larger than the CISH-positive area. Among the histological subtypes of lung adenocarcinoma, the solid predominant subtype was distinguishable by its infrequent EGFR mutations. EGFR gene mutations preceded changes in oncogenic drive, more so than did EGFR gene number alterations during the developmental process of lung adenocarcinoma. PMID:24355440

  2. Alisol B 23-acetate protects against ANIT-induced hepatotoxity and cholestasis, due to FXR-mediated regulation of transporters and enzymes involved in bile acid homeostasis.

    Science.gov (United States)

    Meng, Qiang; Chen, Xin-Li; Wang, Chang-Yuan; Liu, Qi; Sun, Hui-Jun; Sun, Peng-Yuan; Huo, Xiao-Kui; Liu, Zhi-Hao; Yao, Ji-Hong; Liu, Ke-Xin

    2015-03-15

    Intrahepatic cholestasis is a clinical syndrome with systemic and intrahepatic accumulation of excessive toxic bile acids that ultimately cause hepatobiliary injury. Appropriate regulation of bile acids in hepatocytes is critically important for protection against liver injury. In the present study, we characterized the protective effect of alisol B 23-acetate (AB23A), a natural triterpenoid, on alpha-naphthylisothiocyanate (ANIT)-induced liver injury and intrahepatic cholestasis in mice and further elucidated the mechanisms in vivo and in vitro. AB23A treatment dose-dependently protected against liver injury induced by ANIT through reducing hepatic uptake and increasing efflux of bile acid via down-regulation of hepatic uptake transporters (Ntcp) and up-regulation of efflux transporter (Bsep, Mrp2 and Mdr2) expression. Furthermore, AB23A reduced bile acid synthesis through repressing Cyp7a1 and Cyp8b1, increased bile acid conjugation through inducing Bal, Baat and bile acid metabolism through an induction in gene expression of Sult2a1. We further demonstrate the involvement of farnesoid X receptor (FXR) in the hepatoprotective effect of AB23A. The changes in transporters and enzymes, as well as ameliorative liver histology in AB23A-treated mice were abrogated by FXR antagonist guggulsterone in vivo. In vitro evidences also directly demonstrated the effect of AB23A on FXR activation in a dose-dependent manner using luciferase reporter assay in HepG2 cells. In conclusion, AB23A produces protective effect against ANIT-induced hepatotoxity and cholestasis, due to FXR-mediated regulation of transporters and enzymes. PMID:25655198

  3. Ethyl Acetate Fraction of Amomum xanthioides Exerts Antihepatofibrotic Actions via the Regulation of Fibrogenic Cytokines in a Dimethylnitrosamine-Induced Rat Model

    Science.gov (United States)

    Lee, Sung-Bae; Kim, Hyeong-Geug; Kim, Hyo-Seon; Lee, Jin-Seok; Im, Hwi-Jin; Kim, Won-Yong

    2016-01-01

    Amomum xanthioides has been traditionally used to treat diverse digestive system disorders in the Asian countries. We investigated antihepatofibrotic effects of ethyl acetate fraction of Amomum xanthioides (EFAX). Liver fibrosis is induced by dimethylnitrosamine (DMN) injection (intraperitoneally, 10 mg/kg of DMN for 4 weeks to Sprague-Dawley rats). EFAX (25 or 50 mg/kg), silymarin (50 mg/kg), or distilled water was orally administered every day. The DMN injection drastically altered body and organ mass, serum biochemistry, and platelet count, while EFAX treatment significantly attenuated this alteration. Severe liver fibrosis is determined by trichrome staining and measurement of hydroxyproline contents. EFAX treatment significantly attenuated these symptoms as well as the increase in oxidative by-products of lipid and protein metabolism in liver tissues. DMN induced a dramatic activation of hepatic stellate cells and increases in the levels of protein and gene expression of transforming growth factor-beta (TGF-β), platelet derived growth factor-beta (PDGF-β), and connective tissue growth factor (CTGF). Immunohistochemical analyses revealed increases in the levels of protein and gene expression of α-smooth muscle actin. These alterations were significantly normalized by EFAX treatment. Our findings demonstrate the potent antihepatofibrotic properties of EFAX via modulation of fibrogenic cytokines, especially TGF-β in the liver fibrosis rat model. PMID:27594891

  4. A soft coral-derived compound, 11-epi-sinulariolide acetate suppresses inflammatory response and bone destruction in adjuvant-induced arthritis.

    Science.gov (United States)

    Lin, Yen-You; Jean, Yen-Hsuan; Lee, Hsin-Pai; Chen, Wu-Fu; Sun, Yu-Min; Su, Jui-Hsin; Lu, Yi; Huang, Shi-Ying; Hung, Han-Chun; Sung, Ping-Jyun; Sheu, Jyh-Horng; Wen, Zhi-Hong

    2013-01-01

    In recent years, a significant number of metabolites with potent anti-inflammatory properties have been discovered from marine organisms, and several of these compounds are now under clinical trials. In the present study, we isolated 11-epi-sinulariolide acetate (Ya-s11), a cembrane-type compound with anti-inflammatory effects, from the Formosa soft coral Sinularia querciformis. Preliminary screening revealed that Ya-s11 significantly inhibited the expression of the proinflammatory proteins induced nitric oxide synthase and cyclooxygenase-2 in lipopolysaccharide-stimulated murine macrophages. We also examined the therapeutic effects of Ya-s11 on adjuvant-induced arthritis (AIA) in female Lewis rats, which demonstrate features similar to human rheumatoid arthritis (RA). Animal experiments revealed that Ya-s11 (subcutaneously 9 mg/kg once every 2 days from day 7 to day 28 postimmunization) significantly inhibited AIA characteristics. Moreover, Ya-s11 also attenuated protein expression of cathepsin K, matrix metalloproteinases-9 (MMP-9), tartrate-resistant acid phosphatase (TRAP), and tumor necrosis factor-α (TNF-α) in ankle tissues of AIA-rats. Based on its attenuation of the expression of proinflammatory proteins and disease progression in AIA rats, the marine-derived compound Ya-s11 may serve as a useful therapeutic agent for the treatment of RA.

  5. Nordihydroguaiaretic Acid from Creosote Bush (Larrea tridentata Mitigates 12-O-Tetradecanoylphorbol-13-Acetate-Induced Inflammatory and Oxidative Stress Responses of Tumor Promotion Cascade in Mouse Skin

    Directory of Open Access Journals (Sweden)

    Shakilur Rahman

    2011-01-01

    Full Text Available Nordihydroguaiaretic acid (NDGA is a phenolic antioxidant found in the leaves and twigs of the evergreen desert shrub, Larrea tridentata (Sesse and Moc. ex DC Coville (creosote bush. It has a long history of traditional medicinal use by the Native Americans and Mexicans. The modulatory effects of topically applied NDGA was studied on acute inflammatory and oxidative stress responses in mouse skin induced by stage I tumor promoting agent, 12-O-tetradecanoylphorbol-13-acetate (TPA. Double TPA treatment adversely altered many of the marker responses of stage I skin tumor promotion cascade. Pretreatment of NDGA in TPA-treated mice mitigated cutaneous lipid peroxidation and inhibited production of hydrogen peroxide. NDGA treatment also restored reduced glutathione level and activities of antioxidant enzymes. Elevated activities of myeloperoxidase, xanthine oxidase and skin edema formation in TPA-treated mice were also lowered by NDGA indicating a restrained inflammatory response. Furthermore, results of histological study demonstrated inhibitory effect of NDGA on cellular inflammatory responses. This study provides a direct evidence of antioxidative and anti-inflammatory properties of NDGA against TPA-induced cutaneous inflammation and oxidative stress corroborating its chemopreventive potential against skin cancer.

  6. A Metabolic Shift toward Pentose Phosphate Pathway Is Necessary for Amyloid Fibril- and Phorbol 12-Myristate 13-Acetate-induced Neutrophil Extracellular Trap (NET) Formation.

    Science.gov (United States)

    Azevedo, Estefania P; Rochael, Natalia C; Guimarães-Costa, Anderson B; de Souza-Vieira, Thiago S; Ganilho, Juliana; Saraiva, Elvira M; Palhano, Fernando L; Foguel, Debora

    2015-09-01

    Neutrophils are the main defense cells of the innate immune system. Upon stimulation, neutrophils release their chromosomal DNA to trap and kill microorganisms and inhibit their dissemination. These chromatin traps are termed neutrophil extracellular traps (NETs) and are decorated with granular and cytoplasm proteins. NET release can be induced by several microorganism membrane components, phorbol 12-myristate 13-acetate as well as by amyloid fibrils, insoluble proteinaceous molecules associated with more than 40 different pathologies among other stimuli. The intracellular signaling involved in NET formation is complex and remains unclear for most tested stimuli. Herein we demonstrate that a metabolic shift toward the pentose phosphate pathway (PPP) is necessary for NET release because glucose-6-phosphate dehydrogenase (G6PD), an important enzyme from PPP, fuels NADPH oxidase with NADPH to produce superoxide and thus induce NETs. In addition, we observed that mitochondrial reactive oxygen species, which are NADPH-independent, are not effective in producing NETs. These data shed new light on how the PPP and glucose metabolism contributes to NET formation.

  7. Ethyl Acetate Fraction of Amomum xanthioides Exerts Antihepatofibrotic Actions via the Regulation of Fibrogenic Cytokines in a Dimethylnitrosamine-Induced Rat Model

    Directory of Open Access Journals (Sweden)

    Sung-Bae Lee

    2016-01-01

    Full Text Available Amomum xanthioides has been traditionally used to treat diverse digestive system disorders in the Asian countries. We investigated antihepatofibrotic effects of ethyl acetate fraction of Amomum xanthioides (EFAX. Liver fibrosis is induced by dimethylnitrosamine (DMN injection (intraperitoneally, 10 mg/kg of DMN for 4 weeks to Sprague-Dawley rats. EFAX (25 or 50 mg/kg, silymarin (50 mg/kg, or distilled water was orally administered every day. The DMN injection drastically altered body and organ mass, serum biochemistry, and platelet count, while EFAX treatment significantly attenuated this alteration. Severe liver fibrosis is determined by trichrome staining and measurement of hydroxyproline contents. EFAX treatment significantly attenuated these symptoms as well as the increase in oxidative by-products of lipid and protein metabolism in liver tissues. DMN induced a dramatic activation of hepatic stellate cells and increases in the levels of protein and gene expression of transforming growth factor-beta (TGF-β, platelet derived growth factor-beta (PDGF-β, and connective tissue growth factor (CTGF. Immunohistochemical analyses revealed increases in the levels of protein and gene expression of α-smooth muscle actin. These alterations were significantly normalized by EFAX treatment. Our findings demonstrate the potent antihepatofibrotic properties of EFAX via modulation of fibrogenic cytokines, especially TGF-β in the liver fibrosis rat model.

  8. Suppression of 12-O-tetradecanoylphorbol-13-acetate (TPA-induced skin inflammation in mice by transduced Tat-Annexin protein

    Directory of Open Access Journals (Sweden)

    Sun Hwa Lee1,#, Dae Won Kim1,#, Seon Ae Eom1, Se-Young Jun1, Meeyoung Park1, Duk-Soo Kim2, Hyung Joo Kwon3, Hyeok Yil Kwon4, Kyu Hyung Han1, Jinseu Park1, Hyun Sook Hwang1, Won Sik Eum1,* & Soo Young Choi1,*

    2012-06-01

    Full Text Available We examined that the protective effects of ANX1 on 12-O-tetradecanoylphorbol-13-acetate (TPA-induced skin inflammationin animal models using a Tat-ANX1 protein. Topicalapplication of the Tat-ANX1 protein markedly inhibited TPAinducedear edema and expression levels of cyclooxygenase-2(COX-2 as well as pro-inflammatory cytokines such as interleukin-1 beta (IL-1β, IL-6, and tumor necrosis factor-alpha(TNF-α. Also, application of Tat-ANX1 protein significantlyinhibited nuclear translocation of nuclear factor-kappa B(NF-κB and phosphorylation of p38 and extracellular signalregulatedkinase (ERK mitogen-activated protein kinase(MAPK in TPA-treated mice ears. The results indicate thatTat-ANX1 protein inhibits the inflammatory response byblocking NF-κB and MAPK activation in TPA-induced miceears. Therefore, the Tat-ANX1 protein may be useful as atherapeutic agent against inflammatory skin diseases.

  9. In Vivo Antioxidant and Anti-Skin-Aging Activities of Ethyl Acetate Extraction from Idesia polycarpa Defatted Fruit Residue in Aging Mice Induced by D-Galactose

    Directory of Open Access Journals (Sweden)

    Yang Ye

    2014-01-01

    Full Text Available Two different concentrations of D-galactose (D-gal induced organism and skin aging in Kunming mice were used to examine comprehensively the antioxidant and antiaging activities of ethyl acetate extraction (EAE from Idesia polycarpa defatted fruit residue for the first time. The oxygen radical absorbance capacity (ORAC of EAE was 13.09 ± 0.11 μmol Trolox equivalents (TE/mg, which showed EAE had great in vitro free radical scavenging and antioxidant activity. Biochemical indexes and morphological analysis of all tested tissues showed that EAE could effectively improve the total antioxidant capacity (T-AOC of the antioxidant defense system of the aging mice, enhance the activities of superoxide dismutase (SOD, catalase (CAT, and glutathione peroxidase (GSH-Px of tissues and serum, increase glutathione (GSH content and decrease the malondialdehyde (MDA content, and maintain the skin collagen, elastin, and moisture content. Meanwhile, EAE could effectively attenuate the morphological damage in brain, liver, kidney, and skin induced by D-gal and its effect was not less than that of the well-known L-ascorbic acid (VC and α-tocopherol (VE. Overall, EAE is a potent natural antiaging agent with great antioxidant activity, which can be developed as a new medicine and cosmetic for the treatment of age-related conditions.

  10. Ethyl Acetate Fraction of Amomum xanthioides Exerts Antihepatofibrotic Actions via the Regulation of Fibrogenic Cytokines in a Dimethylnitrosamine-Induced Rat Model.

    Science.gov (United States)

    Lee, Sung-Bae; Kim, Hyeong-Geug; Kim, Hyo-Seon; Lee, Jin-Seok; Im, Hwi-Jin; Kim, Won-Yong; Son, Chang-Gue

    2016-01-01

    Amomum xanthioides has been traditionally used to treat diverse digestive system disorders in the Asian countries. We investigated antihepatofibrotic effects of ethyl acetate fraction of Amomum xanthioides (EFAX). Liver fibrosis is induced by dimethylnitrosamine (DMN) injection (intraperitoneally, 10 mg/kg of DMN for 4 weeks to Sprague-Dawley rats). EFAX (25 or 50 mg/kg), silymarin (50 mg/kg), or distilled water was orally administered every day. The DMN injection drastically altered body and organ mass, serum biochemistry, and platelet count, while EFAX treatment significantly attenuated this alteration. Severe liver fibrosis is determined by trichrome staining and measurement of hydroxyproline contents. EFAX treatment significantly attenuated these symptoms as well as the increase in oxidative by-products of lipid and protein metabolism in liver tissues. DMN induced a dramatic activation of hepatic stellate cells and increases in the levels of protein and gene expression of transforming growth factor-beta (TGF-β), platelet derived growth factor-beta (PDGF-β), and connective tissue growth factor (CTGF). Immunohistochemical analyses revealed increases in the levels of protein and gene expression of α-smooth muscle actin. These alterations were significantly normalized by EFAX treatment. Our findings demonstrate the potent antihepatofibrotic properties of EFAX via modulation of fibrogenic cytokines, especially TGF-β in the liver fibrosis rat model. PMID:27594891

  11. The Effect of Calendula Officinalis in Therapy of Acetic Acid Induced Ulcerative Colitis in Dog as an Animal Model

    OpenAIRE

    Mehrabani, D; M. Ziaei; Hosseini, S.V; Ghahramani, L; Bananzadeh, A M; Ashraf, M. J.; Amini, A; Amini, M; Tanideh, N

    2011-01-01

    Background In patients with ulcerative colitis (UC), the repeated cycle of injury and repair of intestinal mucosa has been reported to increase the risk of colon cancer. So, a safe and efficient therapy is required for the treatment and prophylaxis for the disease.This study aims to investigate the efficacy of Calendula officinalis extract in treatment of experimentally induced ulcerative colitis in dog animal model. Methods During fall 2010, 10 out-bred female German dogs (1-2 years old; wei...

  12. Uranyl Acetate Induces Oxidative Stress and Mitochondrial Membrane Potential Collapse in the Human Dermal Fibroblast Primary Cells

    OpenAIRE

    Daraie, Bahram; Pourahmad, Jalal; Hamidi-Pour, Neda; Hosseini, Mir-Jamal; Shaki, Fatemeh; Soleimani, Masoud

    2012-01-01

    Cytotoxicity of depleted uranium, as a byproduct of military has been came to spotlight in recent decades. DU is known as a chemical rather than radioactive hazard and efforts to illustrating its mechanism is undergo, but the precise complete molecular mechanisms are still unclear. Recent studies showed that uranium induces biological changes in many different target tissues, such as the kidney, brain and skin. The aim of this study was to assess the impact of depleted uranium exposure at the...

  13. Interaction between EGFR and EphA2

    DEFF Research Database (Denmark)

    Larsen, Alice Bjerregaard

    2010-01-01

    Enhanced or altered epidermal growth factor receptor (EGFR) activity has been reported in many human cancers and several molecular targeting therapies has been developed. However, despite intense research, therapies targeting EGFR have shown conflicting results in clinical studies, indicating...... the involvement of other important molecular players. Several different EGFR mutations have been reported in cancer, one of which is the cancer specific type III EGFR deletion mutant (EGFRvIII, de2-7EGFR, ¿EGFR). In a global search for EGFR and EGFRvIII regulated genes we identified the receptor tyrosine kinase...... that EphA2 expression in in vitro cultured cells is restricted to cells growing adherently. EphA2 and EGFR are both cell surface trans-membrane proteins and we have found that the two receptors co-localize on human cancer cells. EGFR and EphA2 co-immunoprecipitates and their interactions affects receptor...

  14. Alisol B 23-acetate protects against ANIT-induced hepatotoxity and cholestasis, due to FXR-mediated regulation of transporters and enzymes involved in bile acid homeostasis

    Energy Technology Data Exchange (ETDEWEB)

    Meng, Qiang; Chen, Xin-li; Wang, Chang-yuan; Liu, Qi; Sun, Hui-jun; Sun, Peng-yuan; Huo, Xiao-kui; Liu, Zhi-hao; Yao, Ji-hong; Liu, Ke-xin, E-mail: kexinliu@dlmedu.edu.cn

    2015-03-15

    Intrahepatic cholestasis is a clinical syndrome with systemic and intrahepatic accumulation of excessive toxic bile acids that ultimately cause hepatobiliary injury. Appropriate regulation of bile acids in hepatocytes is critically important for protection against liver injury. In the present study, we characterized the protective effect of alisol B 23-acetate (AB23A), a natural triterpenoid, on alpha-naphthylisothiocyanate (ANIT)-induced liver injury and intrahepatic cholestasis in mice and further elucidated the mechanisms in vivo and in vitro. AB23A treatment dose-dependently protected against liver injury induced by ANIT through reducing hepatic uptake and increasing efflux of bile acid via down-regulation of hepatic uptake transporters (Ntcp) and up-regulation of efflux transporter (Bsep, Mrp2 and Mdr2) expression. Furthermore, AB23A reduced bile acid synthesis through repressing Cyp7a1 and Cyp8b1, increased bile acid conjugation through inducing Bal, Baat and bile acid metabolism through an induction in gene expression of Sult2a1. We further demonstrate the involvement of farnesoid X receptor (FXR) in the hepatoprotective effect of AB23A. The changes in transporters and enzymes, as well as ameliorative liver histology in AB23A-treated mice were abrogated by FXR antagonist guggulsterone in vivo. In vitro evidences also directly demonstrated the effect of AB23A on FXR activation in a dose-dependent manner using luciferase reporter assay in HepG2 cells. In conclusion, AB23A produces protective effect against ANIT-induced hepatotoxity and cholestasis, due to FXR-mediated regulation of transporters and enzymes. - Highlights: • AB23A has at least three roles in protection against ANIT-induced liver injury. • AB23A decreases Ntcp, and increases Bsep, Mrp2 and Mdr2 expression. • AB23A represses Cyp7a1 and Cyp8b1 through inducing Shp and Fgf15 expression. • AB23A increases bile acid metabolism through inducing Sult2a1 expression. • FXR activation is involved

  15. EGFR inhibitors identified as a potential treatment for chordoma in a focused compound screen.

    Science.gov (United States)

    Scheipl, Susanne; Barnard, Michelle; Cottone, Lucia; Jorgensen, Mette; Drewry, David H; Zuercher, William J; Turlais, Fabrice; Ye, Hongtao; Leite, Ana P; Smith, James A; Leithner, Andreas; Möller, Peter; Brüderlein, Silke; Guppy, Naomi; Amary, Fernanda; Tirabosco, Roberto; Strauss, Sandra J; Pillay, Nischalan; Flanagan, Adrienne M

    2016-07-01

    Chordoma is a rare malignant bone tumour with a poor prognosis and limited therapeutic options. We undertook a focused compound screen (FCS) against 1097 compounds on three well-characterized chordoma cell lines; 154 compounds were selected from the single concentration screen (1 µm), based on their growth-inhibitory effect. Their half-maximal effective concentration (EC50 ) values were determined in chordoma cells and normal fibroblasts. Twenty-seven of these compounds displayed chordoma selective cell kill and 21/27 (78%) were found to be EGFR/ERBB family inhibitors. EGFR inhibitors in clinical development were then studied on an extended cell line panel of seven chordoma cell lines, four of which were sensitive to EGFR inhibition. Sapitinib (AstraZeneca) emerged as the lead compound, followed by gefitinib (AstraZeneca) and erlotinib (Roche/Genentech). The compounds were shown to induce apoptosis in the sensitive cell lines and suppressed phospho-EGFR and its downstream pathways in a dose-dependent manner. Analysis of substituent patterns suggested that EGFR-inhibitors with small aniline substituents in the 4-position of the quinazoline ring were more effective than inhibitors with large substituents in that position. Sapitinib showed significantly reduced tumour growth in two xenograft mouse models (U-CH1 xenograft and a patient-derived xenograft, SF8894). One of the resistant cell lines (U-CH2) was shown to express high levels of phospho-MET, a known bypass signalling pathway to EGFR. Neither amplifications (EGFR, ERBB2, MET) nor mutations in EGFR, ERBB2, ERBB4, PIK3CA, BRAF, NRAS, KRAS, PTEN, MET or other cancer gene hotspots were detected in the cell lines. Our findings are consistent with the reported (p-)EGFR expression in the majority of clinical samples, and provide evidence for exploring the efficacy of EGFR inhibitors in the treatment of patients with chordoma and studying possible resistance mechanisms to these compounds in vitro and in vivo. © 2016

  16. The EGFR mutation status affects the relative biological effectiveness of carbon-ion beams in non-small cell lung carcinoma cells.

    Science.gov (United States)

    Amornwichet, Napapat; Oike, Takahiro; Shibata, Atsushi; Nirodi, Chaitanya S; Ogiwara, Hideaki; Makino, Haruhiko; Kimura, Yuka; Hirota, Yuka; Isono, Mayu; Yoshida, Yukari; Ohno, Tatsuya; Kohno, Takashi; Nakano, Takashi

    2015-06-11

    Carbon-ion radiotherapy (CIRT) holds promise to treat inoperable locally-advanced non-small cell lung carcinoma (NSCLC), a disease poorly controlled by standard chemoradiotherapy using X-rays. Since CIRT is an extremely limited medical resource, selection of NSCLC patients likely to benefit from it is important; however, biological predictors of response to CIRT are ill-defined. The present study investigated the association between the mutational status of EGFR and KRAS, driver genes frequently mutated in NSCLC, and the relative biological effectiveness (RBE) of carbon-ion beams over X-rays. The assessment of 15 NSCLC lines of different EGFR/KRAS mutational status and that of isogenic NSCLC lines expressing wild-type or mutant EGFR revealed that EGFR-mutant NSCLC cells, but not KRAS-mutant cells, show low RBE. This was attributable to (i) the high X-ray sensitivity of EGFR-mutant cells, since EGFR mutation is associated with a defect in non-homologous end joining, a major pathway for DNA double-strand break (DSB) repair, and (ii) the strong cell-killing effect of carbon-ion beams due to poor repair of carbon-ion beam-induced DSBs regardless of EGFR mutation status. These data highlight the potential of EGFR mutation status as a predictor of response to CIRT, i.e., CIRT may show a high therapeutic index in EGFR mutation-negative NSCLC.

  17. Decreased Autocrine EGFR Signaling in Metastatic Breast Cancer Cells Inhibits Tumor Growth in Bone and Mammary Fat Pad

    OpenAIRE

    Nickerson, Nicole K.; Mohammad, Khalid S.; Gilmore, Jennifer L.; Crismore, Erin; Bruzzaniti, Angela; Guise, Theresa A.; Foley, John

    2012-01-01

    Breast cancer metastasis to bone triggers a vicious cycle of tumor growth linked to osteolysis. Breast cancer cells and osteoblasts express the epidermal growth factor receptor (EGFR) and produce ErbB family ligands, suggesting participation of these growth factors in autocrine and paracrine signaling within the bone microenvironment. EGFR ligand expression was profiled in the bone metastatic MDA-MB-231 cells (MDA-231), and agonist-induced signaling was examined in both breast cancer and oste...

  18. Concordance of KRAS/BRAF Mutation Status in Metastatic Colorectal Cancer before and after Anti-EGFR Therapy

    Directory of Open Access Journals (Sweden)

    S. Gattenlöhner

    2009-01-01

    Full Text Available Anti-EGFR targeted therapy is a potent strategy in the treatment of metastatic colorectal cancer (mCRC but activating mutations in the KRAS gene are associated with poor response to this treatment. Therefore, KRAS mutation analysis is employed in the selection of patients for EGFR-targeted therapy and various studies have shown a high concordance between the mutation status in primary CRC and corresponding metastases. However, although development of therapy related resistance occurs also in the context of novel drugs such as tyrosine kinase-inhibitors the effect of the anti-EGFR treatment on the KRAS/BRAF mutation status itself in recurrent mCRC has not yet been clarified. Therefore, we analyzed 21 mCRCs before/after anti-EGFR therapy and found a pre-/posttherapeutic concordance of the KRAS/BRAF mutation status in 20 of the 21 cases examined. In the one discordant case, further analyses revealed that a tumor mosaicism or multiple primary tumors were present, indicating that anti-EGFR therapy has no influence on KRAS/BRAF mutation status in mCRC. Moreover, as the preselection of patients with a KRASwt genotype for anti-EGFR therapy has become a standard procedure, sample sets such ours might be the basis for future studies addressing the identification of potential anti-EGFR therapy induced genetic alterations apart from KRAS/BRAF mutations.

  19. Placebo controlled, crossover validation study of oral ibuprofen and topical hydrocortisone-21-acetate for a model of ultraviolet B radiation (UVR-induced pain and inflammation

    Directory of Open Access Journals (Sweden)

    Rother M

    2011-10-01

    Full Text Available Matthias Rother, Ilka RotherDepartment of Clinical Operations, X-pert Med GmbH, Graefelfing, GermanyBackground: Pain related to ultraviolet B radiation (UVR induced sunburn is an established, simple, acute pain model. One of the major criticisms is related to the potential dermal adverse events caused by the UVR exposure. This study tried to validate the model for oral and topical drugs and to define the minimum required UVR exposure.Methods: This subject- and observer-blinded, placebo-controlled, crossover study evaluated 600 mg oral ibuprofen (IB and topical hydrocortisone-21-acetate (HC twice daily (bid in 24 healthy volunteers. Treatment started immediately after irradiation and again at 12 hours, 24 hours, and 36 hours post-UVR. Assessment of hyperalgesia to heat and signs of inflammation (erythema, skin temperature for all areas was performed after UVR and again at 6, 12, 24, 36, and 48 hours. Subjects returned within 4–11 days to the study site for the second period of the study. As in the first period, subjects received HC at one side and topical placebo on the other side, but oral treatment was crossed-over.Results: The primary analysis failed to show the expected superiority of the IB-group vs the placebo group in period 1 of the study. Evaluating period 2 alone clearly showed the expected treatment effects of IB for erythema and heat pain threshold. The results were less pronounced for skin temperature. In contrast to IB vs oral placebo, there were no differences in treatment response between HC and topical placebo. UVR at all dosages induced profound erythema and reduction of heat pain threshold without causing blisters or other unexpected discomfort to the subjects. The changes were almost linear between 1 and 2 minimal erythema doses (MED, whereas the change from 2 to 3 MED was less pronounced.Conclusion: Use of 2 MED in upcoming studies seems to be reasonable to limit subjects' UVB exposure. The following procedural changes are

  20. Changes in saccharin preference behavior as a primary outcome to evaluate pain and analgesia in acetic acid-induced visceral pain in mice

    Science.gov (United States)

    de la Puente, Beatriz; Romero-Alejo, Elizabeth; Vela, José Miguel; Merlos, Manuel; Zamanillo, Daniel; Portillo-Salido, Enrique

    2015-01-01

    Reflex-based procedures are important measures in preclinical pain studies that evaluate stimulated behaviors. These procedures, however, are insufficient to capture the complexity of the pain experience, which is often associated with the depression of several innate behaviors. While recent studies have made efforts to evidence the suppression of some positively motivated behaviors in certain pain models, they are still far from being routinely used as readouts for analgesic screening. Here, we characterized and compared the effect of the analgesic ibuprofen (Ibu) and the stimulant, caffeine, in assays of acute pain-stimulated and pain-depressed behavior. Intraperitoneal injection of acetic acid (AA) served as a noxious stimulus to stimulate a writhing response or depress saccharin preference and locomotor activity (LMA) in mice. AA injection caused the maximum number of writhes between 5 and 20 minutes after administration, and writhing almost disappeared 1 hour later. AA-treated mice showed signs of depression-like behaviors after writhing resolution, as evidenced by reduced locomotion and saccharin preference for at least 4 and 6 hours, respectively. Depression-like behaviors resolved within 24 hours after AA administration. A dose of Ibu (40 mg/kg) – inactive to reduce AA-induced abdominal writhing – administered before or after AA injection significantly reverted pain-induced saccharin preference deficit. The same dose of Ibu also significantly reverted the AA-depressed LMA, but only when it was administered after AA injection. Caffeine restored locomotion – but not saccharin preference – in AA-treated mice, thus suggesting that the reduction in saccharin preference – but not in locomotion – was specifically sensitive to analgesics. In conclusion, AA-induced acute pain attenuated saccharin preference and LMA beyond the resolution of writhing behavior, and the changes in the expression of hedonic behavior, such as sweet taste preference, can be

  1. Nimotuzumab promotes radiosensitivity of EGFR-overexpression esophageal squamous cell carcinoma cells by upregulating IGFBP-3

    Directory of Open Access Journals (Sweden)

    Zhao Lei

    2012-12-01

    Full Text Available Abstract Background Epidermal growth factor receptor (EGFR is suggested to predict the radiosensitivity and/or prognosis of human esophageal squamous cell carcinoma (ESCC. The objective of this study was to investigate the efficacy of Nimotuzumab (an anti-EGFR monoclonal antibody on ESCC radiotherapy (RT and underlying mechanisms. Methods Nimotuzumab was administrated to 2 ESCC cell lines KYSE30 and TE-1 treated with RT. Cell growth, colony formation and apoptosis were used to measure anti-proliferation effects. The method of RNA interference was used to investigate the role of insulin-like growth factor binding protein-3 (IGFBP-3 in ESCC cells radiosensitivity treated with Nimotuzumab. In vivo effect of Nimotuzumab on ESCC radiotherapy was done using a mouse xenograft model. Results Nimotuzumab enhanced radiation response of KYSE30 cells (with high EGFR expression in vitro, as evidenced by increased radiation-inhibited cell growth and colony formation and radiation-mediated apoptosis. Mechanism study revealed that Nimotuzumab inhibited phosphorylated EGFR (p-EGFR induced by EGF in KYSE30 cells. In addition, knockdown of IGFBP-3 by short hairpin RNA significantly reduced KYSE30 cells radiosensitivity (PP>0.05. In KYSE30 cell xenografts, Nimotuzumab combined with radiation led to significant tumor growth delay, compared with that of radiation alone (P=0.029, and also with IGFBP-3 up-regulation in tumor tissue. Conclusions Nimotuzumab could enhance the RT effect of ESCC cells with a functional active EGFR pathway. In particular, the increased ESCC radiosensitivity by Nimotuzumab might be dependent on the up-regulation of IGFBP-3 through EGFR-dependent pathway.

  2. Honey prevents neurobehavioural deficit and oxidative stress induced by lead acetate exposure in male Wistar rats- a preliminary study.

    Science.gov (United States)

    Abdulmajeed, Wahab Imam; Sulieman, Habeeb Bolakale; Zubayr, Maymunah Oloruntosin; Imam, Aminu; Amin, Abdulbasit; Biliaminu, Sikiru Abayomi; Oyewole, Lukuman Aboyeji; Owoyele, Bamidele Victor

    2016-02-01

    This research sought to investigate the possible neuroprotective effects of honey against lead (Pb)-induced neurotoxicity. Twenty four male Wistar rats were divided into four groups: Control group that received 1 ml/kg distilled orally for 28 days; while groups II-IV received 0.2% lead in drinking water and 1 ml/kg of distilled water, 1 ml/kg of honey, 1.5 ml/kg of honey respectively for 28 days. Anxiety and exploratory activities were determined in the open field test. Memory function was determined using Morris water maze after which the animals were sacrificed. The brains were then excised, homogenized and Lipid peroxidation (MDA), Superoxide dismutase (SOD), Catalase, Glutathione (GSH) and Glutathione -S- Transferase (GST) activities were determined in the brains. Results showed that lead exposure causes decrease in locomotor and exploratory activities; increase anxiety, memory impairment, lipid peroxidation and decrease antioxidant activities. However, co-administration of honey with lead inhibited neurotoxicity as indicated by the improvement in memory function as evidenced by decreased latency period and increased in time spent in target quadrant in honey-fed rats compared to the lead-exposed animals. Furthermore, honey increased locomotion, exploration and decreased anxiety in lead-exposed rats as indicated by the frequency of rearing, freezing duration and the number of line crossed by animals. Also administration of honey improves antioxidant activities as shown by increased brain SOD, GST and GSH activities compared to the lead-treated groups but no significant effect on MDA level. It can be concluded that honey has neuroprotective effects against lead-induced cognitive deficit probably by enhancing antioxidant activities. PMID:26435406

  3. Honey prevents neurobehavioural deficit and oxidative stress induced by lead acetate exposure in male Wistar rats- a preliminary study.

    Science.gov (United States)

    Abdulmajeed, Wahab Imam; Sulieman, Habeeb Bolakale; Zubayr, Maymunah Oloruntosin; Imam, Aminu; Amin, Abdulbasit; Biliaminu, Sikiru Abayomi; Oyewole, Lukuman Aboyeji; Owoyele, Bamidele Victor

    2016-02-01

    This research sought to investigate the possible neuroprotective effects of honey against lead (Pb)-induced neurotoxicity. Twenty four male Wistar rats were divided into four groups: Control group that received 1 ml/kg distilled orally for 28 days; while groups II-IV received 0.2% lead in drinking water and 1 ml/kg of distilled water, 1 ml/kg of honey, 1.5 ml/kg of honey respectively for 28 days. Anxiety and exploratory activities were determined in the open field test. Memory function was determined using Morris water maze after which the animals were sacrificed. The brains were then excised, homogenized and Lipid peroxidation (MDA), Superoxide dismutase (SOD), Catalase, Glutathione (GSH) and Glutathione -S- Transferase (GST) activities were determined in the brains. Results showed that lead exposure causes decrease in locomotor and exploratory activities; increase anxiety, memory impairment, lipid peroxidation and decrease antioxidant activities. However, co-administration of honey with lead inhibited neurotoxicity as indicated by the improvement in memory function as evidenced by decreased latency period and increased in time spent in target quadrant in honey-fed rats compared to the lead-exposed animals. Furthermore, honey increased locomotion, exploration and decreased anxiety in lead-exposed rats as indicated by the frequency of rearing, freezing duration and the number of line crossed by animals. Also administration of honey improves antioxidant activities as shown by increased brain SOD, GST and GSH activities compared to the lead-treated groups but no significant effect on MDA level. It can be concluded that honey has neuroprotective effects against lead-induced cognitive deficit probably by enhancing antioxidant activities.

  4. Co-administration of α-lipoic acid and cyclosporine aggravates colon ulceration of acetic acid-induced ulcerative colitis via facilitation of NO/COX-2/miR-210 cascade.

    Science.gov (United States)

    El-Gowelli, Hanan M; Saad, Evan I; Abdel-Galil, Abdel-Galil A; Ibrahim, Einas R

    2015-11-01

    In this work, α-lipoic acid and cyclosporine demonstrated significant protection against acetic acid-induced ulcerative colitis in rats. We proposed that α-lipoic acid and cyclosporine co-administration might modulate their individual effects. Induction of ulcerative colitis in rats was performed by intra-rectal acetic acid (5% v/v) administration for 3 consecutive days. Effects of individual or combined used of α-lipoic acid (35 mg/kg ip) or cyclosporine (5mg/kg sc) for 6 days starting 2 days prior to acetic acid were assessed. Acetic acid caused colon ulceration, bloody diarrhea and weight loss. Histologically, there was mucosal atrophy and inflammatory cells infiltration in submucosa, associated with depletion of colon reduced glutathione, superoxide dismutase and catalase activities and elevated colon malondialdehyde, serum C-reactive protein (C-RP) and tumor necrosis factor-α (TNF-α). Colon gene expression of cyclooxygenase-2 and miR-210 was also elevated. These devastating effects of acetic acid were abolished upon concurrent administration of α-lipoic acid. Alternatively, cyclosporine caused partial protection against acetic acid-induced ulcerative colitis. Cyclosporine did not restore colon reduced glutathione, catalase activity, serum C-RP or TNF-α. Unexpectedly, co-administration of α-lipoic acid and cyclosporine aggravated colon ulceration. Concomitant use of α-lipoic acid and cyclosporine significantly increased nitric oxide production, cyclooxygenase-2 and miR-210 gene expression compared to all other studied groups. The current findings suggest that facilitation of nitric oxide/cyclooxygenase-2/miR-210 cascade constitutes, at least partially, the cellular mechanism by which concurrent use of α-lipoic acid and cyclosporine aggravates colon damage. Collectively, the present work highlights the probable risk of using α-lipoic acid/cyclosporine combination in ulcerative colitis patients.

  5. Synergistic antitumor effect between gefitinib and fractionated irradiation in anaplastic oligodendrogliomas cannot be predicted by the Egfr signaling activity.

    Directory of Open Access Journals (Sweden)

    Sophie Pinel

    Full Text Available In high-grade gliomas, the identification of patients that could benefit from EGFR inhibitors remains a challenge, hindering the use of these agents. Using xenografts models, we evaluated the antitumor effect of the combined treatment "gefitinib + radiotherapy" and aimed to identify the profile of responsive tumors. Expression of phosphorylated proteins involved in the EGFR-dependent signaling pathways was analyzed in 10 glioma models. We focused on three models of anaplastic oligodendrogliomas (TCG2, TCG3 and TCG4 harboring high levels of phospho-EGFR, phospho-AKT and phospho-MEK1. They were treated with gefitinib (GEF 75 mg/kg/day x 5 days/week, for 2 weeks and/or fractionated radiotherapy (RT: 5x2Gy/week for 2 weeks. Our results showed that GEF and/or RT induced significant tumor growth delays. However, only the TCG3 xenografts were highly responsive to the combination GEF+RT, with ∼50% of tumor cure. Phosphoproteins analysis five days after treatment onset demonstrated in TCG3 xenografts, but not in TCG2 model, that the EGFR-dependent pathways were inhibited after GEF treatment. Moreover, TCG3-bearing mice receiving GEF monotherapy exhibited a transient beneficial therapeutic response, rapidly followed by tumor regrowth, along with a major vascular remodeling. Taken together, our data evoked an "EGFR-addictive" behavior for TCG3 tumors. This study confirms that combination of gefitinib with fractionated irradiation could be a potent therapeutic strategy for anaplastic oligodendrogliomas harboring EGFR abnormalities but this treatment seems mainly beneficial for "EGFR-addictive" tumors. Unfortunately, neither the usual molecular markers (EGFR amplification, PTEN loss nor the basal overexpression of phosphoproteins were useful to distinguish this responsive tumor. Evaluating the impact of TKIs on the EGFR-dependent pathways during the treatment might be more relevant, and requires further validation.

  6. Topical application of marine briarane-type diterpenes effectively inhibits 12-O-tetradecanoylphorbol-13-acetate-induced inflammation and dermatitis in murine skin

    Directory of Open Access Journals (Sweden)

    Wei Wen-Chi

    2011-12-01

    Full Text Available Abstract Background Skin is the largest organ in the body, and is directly exposed to extrinsic assaults. As such, the skin plays a central role in host defense and the cutaneous immune system is able to elicit specific local inflammatory and systemic immune responses against harmful stimuli. 12-O-tetradecanoylphorbol-13-acetate (TPA can stimulate acute and chronic inflammation and tumor promotion in skin. TPA-induced dermatitis is thus a useful in vivo pharmacological platform for drug discovery. In this study, the inhibitory effect of briarane-type diterpenes (BrDs from marine coral Briareum excavatum on TPA-induced dermatitis and dendritic cell (DC function was explored. Methods Evans blue dye exudation was used to determine vascular permeability. H&E-stained skin section was used to determine the formation of edema in mouse abdominal skin. We also used immunohistochemistry staining and western blot assays to evaluate the activation of specific inflammation makers and key mediators of signaling pathway in the mouse skin. Furthermore, mouse bone marrow DCs were used to determine the relationship between the chemical structure of BrDs and their regulation of DC function. Results BrD1 remarkably suppressed TPA-induced vascular permeability and edema in skin. At the biochemical level, BrD1 inhibited TPA-induced expression of cyclooxygenase-2, inducible nitric oxide synthase and matrix metalloproteinase-9, the key indicators of cutaneous inflammation. This inhibition was apparently mediated by interference with the Akt/NF-κB-mediated signaling network. BrD1 also inhibited TNF-α and IL-6 expression in LPS-stimulated BMDCs. The 8, 17-epoxide of BrDs played a crucial role in the inhibition of IL-6 expression, and replacement of the C-12 hydroxyl group with longer esters in BrDs gradually decreased this inhibitory activity. Conclusions Our results suggest that BrDs warrant further investigation as natural immunomodulatory agents for control of

  7. Ethanolic extract of roots from Arctium lappa L. accelerates the healing of acetic acid-induced gastric ulcer in rats: Involvement of the antioxidant system.

    Science.gov (United States)

    da Silva, Luisa Mota; Allemand, Alexandra; Mendes, Daniel Augusto G B; Dos Santos, Ana Cristina; André, Eunice; de Souza, Lauro Mera; Cipriani, Thales Ricardo; Dartora, Nessana; Marques, Maria Consuelo Andrade; Baggio, Cristiane Hatsuko; Werner, Maria Fernanda

    2013-01-01

    We evaluate the curative efficacy of the ethanolic extract (EET) of roots from Arctium lappa (bardana) in healing of chronic gastric ulcers induced by 80% acetic acid in rats and additionally studies the possible mechanisms underlying this action. Oral administration of EET (1, 3, 10 and 30mg/kg) reduced the gastric lesion area in 29.2%, 41.4%, 59.3% and 38.5%, respectively, and at 10mg/kg promoted significant regeneration of the gastric mucosa, which was confirmed by proliferating cell nuclear antigen immunohistochemistry. EET (10mg/kg) treatment did not increase the gastric mucus content but restored the superoxide dismutase activity, prevented the reduction of glutathione levels, reduced lipid hydroperoxides levels, inhibited the myeloperoxidase activity and reduced the microvascular permeability. In addition, EET reduced the free radical generation and increased scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals in vitro. Furthermore, intraduodenal EET (10 and 30mg/kg) decreased volume and acidity of gastric secretion. Total phenolic compounds were high in EET (Folin-Ciocalteau assay) and the analysis by liquid chromatography-mass spectrometry revealed that the main compounds present in EET were a serie of hydroxycinnamoylquinic acid isomers. In conclusion, these data reveal that EET promotes regeneration of damaged gastric mucosa, probably through its antisecretory and antioxidative mechanisms.

  8. Proteomics-based Identification of Proteins with Altered Expression Induced by 12-O-Tetradecanoylphorbol 13-acetate in Nasopharyngeal Carcinoma CNE2 Cells

    Institute of Scientific and Technical Information of China (English)

    Pei-Zhou JIANG; Ming GAN; Hua HUANG; Xin-Ming SHEN; Shuang WANG; Kai-Tai YAO

    2005-01-01

    Nasopharyngeal carcinoma (NPC) is a malignancy with high incidence in Southern China and South-East Asia. Etiology studies indicate that chemical carcinogen promoters, such as 12-Otetradecanoylphorbol-13-acetate (TPA), are important factors causing NPC development. However, the mechanism of the TPA effect on NPC remains unclear. In the present study, cells from a poorly differentiated squamous cell carcinoma NPC cell line, CNE2, were stimulated by TPA and proteomics technology was carried out to find protein discrepancies between control and TPA-treated cells. Results revealed that TPA treatment in CNE2 cells could upregulate the expression of "triosephosphate isomerase" and "14-3-3 protein sigma" and downregulate the expression of "reticulocalbin 1 precursor", "nucleophosmin", "mitochondrial matrix protein pl precursor", and "stathmin". The changes in the expression of these genes suggested that TPA induced CNE2 cells to antiproliferation and to apoptosis, which was confirmed by subsequent apoptosis detection. Therefore, the effects of TPA on nasopharyngeal carcinoma cells were distinct from the effects on primary epithelial cells and we suggest reasons for these differences.

  9. Ethanolic extract of roots from Arctium lappa L. accelerates the healing of acetic acid-induced gastric ulcer in rats: Involvement of the antioxidant system.

    Science.gov (United States)

    da Silva, Luisa Mota; Allemand, Alexandra; Mendes, Daniel Augusto G B; Dos Santos, Ana Cristina; André, Eunice; de Souza, Lauro Mera; Cipriani, Thales Ricardo; Dartora, Nessana; Marques, Maria Consuelo Andrade; Baggio, Cristiane Hatsuko; Werner, Maria Fernanda

    2013-01-01

    We evaluate the curative efficacy of the ethanolic extract (EET) of roots from Arctium lappa (bardana) in healing of chronic gastric ulcers induced by 80% acetic acid in rats and additionally studies the possible mechanisms underlying this action. Oral administration of EET (1, 3, 10 and 30mg/kg) reduced the gastric lesion area in 29.2%, 41.4%, 59.3% and 38.5%, respectively, and at 10mg/kg promoted significant regeneration of the gastric mucosa, which was confirmed by proliferating cell nuclear antigen immunohistochemistry. EET (10mg/kg) treatment did not increase the gastric mucus content but restored the superoxide dismutase activity, prevented the reduction of glutathione levels, reduced lipid hydroperoxides levels, inhibited the myeloperoxidase activity and reduced the microvascular permeability. In addition, EET reduced the free radical generation and increased scavenging of 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals in vitro. Furthermore, intraduodenal EET (10 and 30mg/kg) decreased volume and acidity of gastric secretion. Total phenolic compounds were high in EET (Folin-Ciocalteau assay) and the analysis by liquid chromatography-mass spectrometry revealed that the main compounds present in EET were a serie of hydroxycinnamoylquinic acid isomers. In conclusion, these data reveal that EET promotes regeneration of damaged gastric mucosa, probably through its antisecretory and antioxidative mechanisms. PMID:23036453

  10. Potent Systemic Anticancer Activity of Adenovirally Expressed EGFR-Selective TRAIL Fusion Protein

    NARCIS (Netherlands)

    Bremer, Edwin; van Dam, Gooitzen M.; de Bruyn, Marco; van Riezen, Manon; Dijkstra, Marike; Kamps, Gera; Helfrich, Wijnand; Haisma, Hidde

    2008-01-01

    Previously, we demonstrated potent tumor cell-selective pro-apoptotic activity of scFv425:sTRAIL, a recombinant fusion protein comprised of EGFR-directed antibody fragment (scFv425) genetically fused to human soluble TNF-related apoptosis-inducing ligand (sTRAIL). Here, we report on the promising th

  11. SMARCE1 suppresses EGFR expression and controls responses to MET and ALK inhibitors in lung cancer

    NARCIS (Netherlands)

    Papadakis, Andreas I; Sun, Chong; Knijnenburg, Theo A; Xue, Yibo; Grernrum, Wipawadee; Hölzel, Michael; Nijkamp, Wouter; Wessels, Lodewyk F A; Beijersbergen, Roderick L; Bernards, Rene; Huang, Sidong

    2015-01-01

    Recurrent inactivating mutations in components of SWI/SNF chromatin-remodeling complexes have been identified across cancer types, supporting their roles as tumor suppressors in modulating oncogenic signaling pathways. We report here that SMARCE1 loss induces EGFR expression and confers resistance t

  12. Effects of dietary virgin olive oil polyphenols: hydroxytyrosyl acetate and 3, 4-dihydroxyphenylglycol on DSS-induced acute colitis in mice.

    Science.gov (United States)

    Sánchez-Fidalgo, Susana; Villegas, Isabel; Aparicio-Soto, Marina; Cárdeno, Ana; Rosillo, Ma Ángeles; González-Benjumea, Alejandro; Marset, Azucena; López, Óscar; Maya, Inés; Fernández-Bolaños, José G; Alarcón de la Lastra, Catalina

    2015-05-01

    Hydroxytyrosol, a polyphenolic compound from extra virgin olive oil (EVOO) has exhibited an improvement in a model of DSS-induced colitis. However, other phenolic compounds present such as hydroxytyrosyl acetate (HTy-Ac) and 3,4-dihydroxyphenylglycol (DHPG) need to be explored to complete the understanding of the overall effects of EVOO on inflammatory colon mucosa. This study was designed to evaluate the effect of both HTy-Ac and DHPG dietary supplementation in the inflammatory response associated to colitis model. Six-week-old mice were randomized in four dietary groups: sham and control groups received standard diet, and other two groups were fed with HTy-Ac and DHPG, respectively, at 0.1%. After 30 days, all groups except sham received 3% DSS in drinking water for 5 days followed by a regime of 5 days of water. Acute inflammation was evaluated by Disease Activity Index (DAI), histology and myeloperoxidase (MPO) activity. Colonic expression of iNOS, COX-2, MAPKs, NF-kB and FOXP3 were determined by western blotting. Only HTy-Ac-supplemented group showed a significant DAI reduction as well as an improvement of histological damage and MPO. COX-2 and iNOS protein expression were also significantly reduced. In addition, this dietary group down-regulated JNK phosphorylation and prevented the DSS-induced nuclear translocation level of p65. However, no significant differences were observed in the FOXP3 expression. These results demonstrated, for the first time, that HTy-Ac exerts an antiinflammatory effect on acute ulcerative colitis. We concluded that HTy-Ac supplement might provide a basis for developing a new dietary strategy for the prevention of ulcerative colitis.

  13. Anti-inflammatory effect of Pistacia atlantica subsp. kurdica volatile oil and gum on acetic acid-induced acute colitis in rat

    Directory of Open Access Journals (Sweden)

    M. Minaiyan

    2015-04-01

    Full Text Available Background and objectives: Baneh tree or Pistacia atlantica subsp. kurdica is an endemic plant of Iran which belongs to Anacardiaceae family. It has various traditional uses including astringent and anti-diarrheal as well as improving some of the symptoms of gastrointestinal upsets. In this study we decided to investigate the effects of various fractions of baneh gum with different doses in an animal model of ulcerative colitis as one of the important chronic inflammatory bowel diseases of the gastrointestinal tract. Methods: The volatile oil and aqueous baneh gum suspensions were prepared and the constituents of the volatile oil were analyzed by GC/MS. They were used to treat colitis induced by acetic acid 4% in rats. Three doses of gum (100, 200 and 400 mg/kg were administered both orally (p.o. and intra-rectally (i.r. while volatile oil was administered p.o. with doses 100, 200 and 400 µl/kg for four constitutive days. Anti-inflammatory effects of the test compounds were compared with oral prednisolone and hydrocortisone enema. Wet colon weight/ length ratio and tissue damage scores and area as well as indices of colitis and tissue myeloperoxidase activity were evaluated for each specimen. Results: Alpha-pinene was the main constituent of baneh volatile oil (41.23%. We observed therapeutic effects in applied doses of oral gum as well as volatile oil to reduce all indices of colitis and myeloperoxidase activity. Unlike the oral form of gum, its rectal administration was not significantly effective to improve colitis. Conclusion: This research has proved the anti-inflammatory potential of oral gum of Pistacia atlantica subsp. kurdica and its volatile oil in an experimentally induced colitis.

  14. Transforming growth factor-beta activities in 'in vivo' lines of hormone-dependent and independent mammary adenocarcinomas induced by medroxyprogesterone acetate in BALB/c mice.

    Science.gov (United States)

    Elizalde, P V; Lanari, C; Kordon, E; Tezón, J; Charreau, E H

    1990-07-01

    We have determined the presence of transforming growth factor-beta (TGF-beta)-like polypeptides in mammary adenocarcinomas induced by medroxyprogesterone acetate (MPA) in BALB/c mice. In hormone-dependent tumors (HD) from nontreated and MPA-treated mice a high molecular weight (43 kDa) transforming activity was purified by Bio-Gel P-60 chromatography. This TGF was able to confer the neoplastic phenotype on NRK-49F cells without the addition of epidermal growth factor (EGF), though its activity was potentiated by EGF. It did not compete for binding to the EGF receptor, had no mitogenic activity on monolayer cultures of NRK fibroblasts, and was a potent inhibitor of DNA synthesis induced in these cells by EGF and insulin. In HD and hormone-independent tumors (HI) another TGF with a Mr of 13 kDa was isolated. This transforming activity showed the same biological properties as 43 kDa TGF, with the exception that in the absence of EGF it did not stimulate soft agar growth of NRK-49F cells. The synthesis of both factors in 'in vivo' HD tumors seems to be under MPA control, since it is much lower in HD tumors from MPA-treated mice. Further purification of the 13 and 43 kDa TGFs by hydrophobic interaction HPLC demonstrated that each one eluted in a different position, and that their elution profile differed from the TGF-beta from human platelets. The biological activity of the 13 and 43 kDa TGFs was not neutralized by a specific anti-TGF-beta antibody. PMID:2145045

  15. PROTECTIVE EFFECT OF VITAMIN D3 IN METHYLPREDNISOLONE ACETATE (MPA INDUCED LOSS OF BONE METABOLISM MARKERS AND BONE MINERAL DENSITY IN THE LUMBAR SPINE OF RAT

    Directory of Open Access Journals (Sweden)

    I. Ragerdi-Kashani

    2007-05-01

    Full Text Available Although some vitamins have been shown to prevent glucocorticoids induced osteoporosis in short time, the magnitude of this effect remains to be clarified. The aim of this study was to evaluate protective effect of vitamin D3 on methylprednisolone acetate (MPA induced osteoporosis in rats. Twenty-four male Sprague Dawley rats were randomly divided into four groups: Group A (n = 6, was a base line control or normal animals. Group B (n = 6, was treated only normal saline, group C (n = 6, was treated MPA (0.2 mg/kg subcutaneously for 4 weeks (3 times per a week and finally group D (n = 6 were administered MPA resemble to group C and treated by Vitamin D3 (0.1 µg/kg dissolved in ethanol daily. Level of calcium, osteocalcin and acid phosphatase in serum were measured before and after treatment. Also, bone mineral density (BMD of lumber vertebrae was measured by dual energy X-ray absorptiometry. The results showed that the serum calcium level unaffected by MPA in all groups before and after treatment, but the serum osteocalcin level and bone mineral density of lumbar vertebrae were significantly (P < 0.05 decreased in group C compared with groups A and B. In group D serum osteocalcin level increased again significantly (P < 0.05 but increasing of BMD and bone mineral content were not significant. The findings indicate that by using of vitamin D3 in MPA treated rats could increase bone formation and decrease bone resorption.

  16. Pharmacogenomics of EGFR-targeted therapies in non-small cell lung cancer:EGFR and beyond

    Institute of Scientific and Technical Information of China (English)

    Christopher Delaney; Samuel Frank; R Stephanie Huang

    2015-01-01

    Commonly observed aberrations in epidermal growth factor receptor (EGFR) signaling have led to the development of EGFR-targeted therapies for various cancers, including non–small cell lung cancer (NSCLC). EGFR mutations and overexpression have further been shown to modulate sensitivity to these EGFR-targeted therapies in NSCLC and several other types of cancers. However, it is clear that mutations and/or genetic variations in EGFR alone cannot explain all of the variability in the responses of patients with NSCLC to EGFR-targeted therapies. For instance, in addition to EGFR genotype, genetic variations in other members of the signaling pathway downstream of EGFR or variations in paral el receptor tyrosine kinase (RTK) pathways are now recognized to have a significant impact on the efficacy of certain EGFR-targeted therapies. In this review, we highlight the mutations and genetic variations in such genes downstream of EGFR and in parallel RTK pathways. Specifically, the directional effects of these pharmacogenetic factors are discussed with a focus on two commonly prescribed EGFR inhibitors:cetuximab and erlotinib. The results of this comprehensive review can be used to optimize the treatment of NSCLC with EGFR inhibitors. Furthermore, they may provide the rationale for the design of subsequent combination therapies that involve the inhibition of EGFR.

  17. Multilayered proteomics reveals molecular switches dictating ligand-dependent EGFR trafficking

    DEFF Research Database (Denmark)

    Francavilla, Chiara; Papetti, Moreno; Rigbolt, Kristoffer T G;

    2016-01-01

    A fascinating conundrum in cell signaling is how stimulation of the same receptor tyrosine kinase with distinct ligands generates specific outcomes. To decipher the functional selectivity of EGF and TGF-α, which induce epidermal growth factor receptor (EGFR) degradation and recycling, respectively...... identified RAB7 phosphorylation and RCP recruitment to EGFR as switches for EGF and TGF-α outputs, controlling receptor trafficking, signaling duration, proliferation, and migration. By manipulating RCP levels or phosphorylation of RAB7 in EGFR-positive cancer cells, we were able to switch a TGF......, we devised an integrated multilayered proteomics approach (IMPA). We analyzed dynamic changes in the receptor interactome, ubiquitinome, phosphoproteome, and late proteome in response to both ligands in human cells by quantitative MS and identified 67 proteins regulated at multiple levels. We...

  18. LL-37 via EGFR transactivation to promote high glucose-attenuated epithelial wound healing in organ-cultured corneas.

    Science.gov (United States)

    Yin, Jia; Yu, Fu-Shin X

    2010-04-01

    Purpose. Patients with diabetes are at higher risk for delayed corneal reepithelialization and infection. Previous studies indicated that high glucose (HG) impairs epidermal growth factor receptor (EGFR) signaling and attenuates ex vivo corneal epithelial wound healing. The authors investigated the effects of antimicrobial peptide LL-37 on HG-attenuated corneal epithelial EGFR signaling and wound closure. Methods. Human corneal epithelial cells (HCECs) were stimulated with LL-37. Heparin-binding EGF-like growth factor (HB-EGF) shedding was assessed by measuring the release of alkaline phosphatase (AP) in a stable HCEC line expressing HB-EGF-AP. Activation of EGFR, phosphoinositide 3-kinase (PI3K), and extracellular signal-regulated kinases 1/2 (ERK1/2) was determined by Western blot analysis. Corneal epithelial wound closure was assessed in cultured HCECs and porcine corneas. LL-37 expression was determined by immune dot blot. Results. LL-37 induced HB-EGF-AP release and EGFR activation in a dose-dependent manner. LL-37 prolonged EGFR signaling in response to wounding. LL-37 enhanced the closure of a scratch wound in cultured HCECs and partially rescued HG-attenuated wound healing in an EGFR- and a PI3K-dependent manner and restored HG-impaired EGFR signaling in cultured porcine corneas. HG attenuated wounding-induced LL-37 expression in cultured HCECs. Conclusions. LL-37 is a tonic factor promoting EGFR signaling and enhancing epithelial wound healing in normal and high glucose conditions. With both antimicrobial and regenerative capabilities, LL-37 may be a potential therapeutic for diabetic keratopathy.

  19. Liganded thyroid hormone receptor inhibits phorbol 12-O-tetradecanoate-13-acetate-induced enhancer activity via firefly luciferase cDNA.

    Directory of Open Access Journals (Sweden)

    Hiroko Misawa

    Full Text Available Thyroid hormone receptor (TR belongs to the nuclear hormone receptor (NHR superfamily and regulates the transcription of its target genes in a thyroid hormone (T3-dependent manner. While the detail of transcriptional activation by T3 (positive regulation has been clarified, the mechanism of T3-dependent repression (negative regulation remains to be determined. In addition to naturally occurring negative regulations typically found for the thyrotropin β gene, T3-bound TR (T3/TR is known to cause artificial negative regulation in reporter assays with cultured cells. For example, T3/TR inhibits the transcriptional activity of the reporter plasmids harboring AP-1 site derived from pUC/pBR322-related plasmid (pUC/AP-1. Artificial negative regulation has also been suggested in the reporter assay with firefly luciferase (FFL gene. However, identification of the DNA sequence of the FFL gene using deletion analysis was not performed because negative regulation was evaluated by measuring the enzymatic activity of FFL protein. Thus, there remains the possibility that the inhibition by T3 is mediated via a DNA sequence other than FFL cDNA, for instance, pUC/AP-1 site in plasmid backbone. To investigate the function of FFL cDNA as a transcriptional regulatory sequence, we generated pBL-FFL-CAT5 by ligating FFL cDNA in the 5' upstream region to heterologous thymidine kinase promoter in pBL-CAT5, a chloramphenicol acetyl transferase (CAT-based reporter gene, which lacks pUC/AP-1 site. In kidney-derived CV1 and choriocarcinoma-derived JEG3 cells, pBL-FFL-CAT5, but not pBL-CAT5, was strongly activated by a protein kinase C activator, phorbol 12-O-tetradecanoate-13-acetate (TPA. TPA-induced activity of pBL-FFL-CAT5 was negatively regulated by T3/TR. Mutation of nt. 626/640 in FFL cDNA attenuated the TPA-induced activation and concomitantly abolished the T3-dependent repression. Our data demonstrate that FFL cDNA sequence mediates the TPA-induced transcriptional

  20. Changes in saccharin preference behavior as a primary outcome to evaluate pain and analgesia in acetic acid-induced visceral pain in mice

    Directory of Open Access Journals (Sweden)

    de la Puente B

    2015-10-01

    Full Text Available Beatriz de la Puente, Elizabeth Romero-Alejo, José Miguel Vela, Manuel Merlos, Daniel Zamanillo, Enrique Portillo-Salido Department of Pharmacology, Drug Discovery and Preclinical Development, ESTEVE, Barcelona, SpainAbstract: Reflex-based procedures are important measures in preclinical pain studies that evaluate stimulated behaviors. These procedures, however, are insufficient to capture the complexity of the pain experience, which is often associated with the depression of several innate behaviors. While recent studies have made efforts to evidence the suppression of some positively motivated behaviors in certain pain models, they are still far from being routinely used as readouts for analgesic screening. Here, we characterized and compared the effect of the analgesic ibuprofen (Ibu and the stimulant, caffeine, in assays of acute pain-stimulated and pain-depressed behavior. Intraperitoneal injection of acetic acid (AA served as a noxious stimulus to stimulate a writhing response or depress saccharin preference and locomotor activity (LMA in mice. AA injection caused the maximum number of writhes between 5 and 20 minutes after administration, and writhing almost disappeared 1 hour later. AA-treated mice showed signs of depression-like behaviors after writhing resolution, as evidenced by reduced locomotion and saccharin preference for at least 4 and 6 hours, respectively. Depression-like behaviors resolved within 24 hours after AA administration. A dose of Ibu (40 mg/kg – inactive to reduce AA-induced abdominal writhing – administered before or after AA injection significantly reverted pain-induced saccharin preference deficit. The same dose of Ibu also significantly reverted the AA-depressed LMA, but only when it was administered after AA injection. Caffeine restored locomotion – but not saccharin preference – in AA-treated mice, thus suggesting that the reduction in saccharin preference – but not in locomotion – was specifically

  1. Unexpected responses to EGFR inhibition in NSCLC

    Directory of Open Access Journals (Sweden)

    Giulia M. Stella

    2015-01-01

    Full Text Available The presence of activating mutations of the epidermal growth factor receptor (EGFR-gene identifies a distinct and clinically relevant molecular subset of non-small-cell lung cancer. It is now well demonstrated that EGFR tyrosine kinase inhibitors (TKIs gefitinib and erlotinib are superior to standard chemotherapy in this subset of tumors. Nevertheless, in many cases, responses are not durable and last for 6–12 months due to the occurrence of secondary or acquired resistance. Here we present three cases of EGFR-mutant lung adenocarcinomas (ADC, that showed an unexpected response to anti-EGFR small molecules. The first patient presented a continued 89 month-long response to erlotinib in a tumor recurred after surgery and conventional chemotherapy. In the other cases, subclinically persistent tumor in the lung tissue was documented histologically in lung resections performed after partial response to TKI treatment. The persistence of interstitial and endolymphatic tumor cells after TKI treatment might explain the common observation of tumor relapse after TKI discontinuation, and sustain the decision to continue treatment in responsive patients as in our first case.

  2. Unexpected responses to EGFR inhibition in NSCLC

    Science.gov (United States)

    Stella, Giulia M.; Valizia, Claudio; Zorzetto, Michele; Inghilleri, Simona; Valentini, Adele; Dore, Roberto; Colombo, Sara; Valentino, Francesco; Orlandoni, Giulio; Morbini, Patrizia

    2015-01-01

    The presence of activating mutations of the epidermal growth factor receptor (EGFR)-gene identifies a distinct and clinically relevant molecular subset of non-small-cell lung cancer. It is now well demonstrated that EGFR tyrosine kinase inhibitors (TKIs) gefitinib and erlotinib are superior to standard chemotherapy in this subset of tumors. Nevertheless, in many cases, responses are not durable and last for 6–12 months due to the occurrence of secondary or acquired resistance. Here we present three cases of EGFR-mutant lung adenocarcinomas (ADC), that showed an unexpected response to anti-EGFR small molecules. The first patient presented a continued 89 month-long response to erlotinib in a tumor recurred after surgery and conventional chemotherapy. In the other cases, subclinically persistent tumor in the lung tissue was documented histologically in lung resections performed after partial response to TKI treatment. The persistence of interstitial and endolymphatic tumor cells after TKI treatment might explain the common observation of tumor relapse after TKI discontinuation, and sustain the decision to continue treatment in responsive patients as in our first case. PMID:26744648

  3. EGFR mutation frequency and effectiveness of erlotinib

    DEFF Research Database (Denmark)

    Weber, Britta; Hager, Henrik; Sorensen, Boe S;

    2014-01-01

    OBJECTIVES: In 2008, we initiated a prospective study to explore the frequency and predictive value of epidermal growth factor receptor (EGFR) mutations in an unselected population of Danish patients with non-small cell lung cancer offered treatment with erlotinib, mainly in second-line. MATERIALS...

  4. Controlled release low dose medroxyprogesterone acetate (MPA) inhibits the development of mammary tumors induced by dimethyl-benz(a) anthracene in the rat.

    Science.gov (United States)

    Labrie, F; Li, S; Bélanger, A; Côté, J; Mérand, Y; Lepage, M

    1993-01-01

    Medroxyprogesterone acetate (MPA) is well recognized to have beneficial effects for the treatment of advanced breast cancer which are comparable to those achieved with other forms of endocrine therapy. Using mammary tumors induced in the rat by dimethylbenz(a)anthracene (DMBA) as a model, we have studied the possibility that low dose MPA could prevent the development of these tumors. Single subcutaneous injection of Depo-Provera (crystalline suspension of MPA) or MPA encapsulated in biodegradable microspheres of 50:50 poly[DL-lactide-co-glycolide] was given 7 days before oral DMBA. While 63% of intact animals developed palpable mammary tumors within 85 days after DMBA administration, tumor incidence decreased to 28% and 23% in animals who had received 30 mg and 100 mg of Depo-Provera, respectively. The same amounts of MPA delivered in microspheres caused a further decrease in tumor incidence to respective values of 7% and 6%. Average tumor area, on the other hand, decreased from 4.89 cm2 in intact rats to about 0.75 (0.57-0.88) cm2 and approximately 0.20 (0.14-0.22) cm2 in the Depo-Provera and microsphere-treated groups, respectively. Using the 50:50 formulation of poly[DL-lactide-co-glycolide] designed to release MPA at a constant rate for a 4-month period, the serum MPA concentration at 3 months was measured at 4.99 +/- 0.43 ng/ml. Such data suggest that administration of a low dose controlled-release formulation of MPA in 50:50 poly[DL-lactide-co-glycolide] microspheres could well be an efficient and well tolerated approach for the prevention of breast cancer in women. PMID:8251650

  5. CS-3150, a Novel Nonsteroidal Mineralocorticoid Receptor Antagonist, Shows Preventive and Therapeutic Effects On Renal Injury in Deoxycorticosterone Acetate/Salt-Induced Hypertensive Rats.

    Science.gov (United States)

    Arai, Kiyoshi; Morikawa, Yuka; Ubukata, Naoko; Tsuruoka, Hiroyuki; Homma, Tsuyoshi

    2016-09-01

    The present study was designed to assess both preventive and therapeutic effects of (S)-1-(2-Hydroxyethyl)-4-methyl-N-[4-(methylsulfonyl) phenyl]-5-[2-(trifluoromethyl) phenyl]-1H-pyrrole-3-carboxamide (CS-3150), a novel nonsteroidal mineralocorticoid receptor antagonist, on renal injury in deoxycorticosterone acetate (DOCA)/salt-induced hypertensive rats (DOCA rats). From 7 weeks of age, DOCA was subcutaneously administered once a week for 4 weeks to uninephrectomized rats fed a high-salt diet. In experiment 1, CS-3150 (0.3-3 mg/kg) was orally administered once a day for 4 weeks coincident with DOCA administration. In experiment 2, after establishment of renal injury by 4 weeks of DOCA/salt loading, CS-3150 (3 mg/kg) was orally administered once a day for 4 weeks with or without continuous DOCA administration. In experiment 1, DOCA/salt loading significantly increased systolic blood pressure (SBP), which was prevented by CS-3150 in a dose-dependent manner. Development of renal injury (proteinuria, renal hypertrophy, and histopathological changes in glomeruli and tubule) was also suppressed by CS-3150 with inhibition of mRNA expression of fibrosis, inflammation, and oxidative stress markers. In experiment 2, under continuous DOCA treatment, CS-3150 clearly ameliorated existing renal injury without lowering SBP, indicating that CS-3150 regressed renal injury independent of its antihypertensive action. Moreover, CS-3150 treatment in combination with withdrawal of DOCA showed further therapeutic effect on renal injury accompanied by reduction in SBP. These results demonstrate that CS-3150 not only prevents but also ameliorates hypertension and renal injury in DOCA rats. Therefore, CS-3150 could be a promising agent for the treatment of hypertension and renal disorders, and may have potential to promote regression of renal injury. PMID:27384074

  6. In vivo and in vitro antitumor activity of oxaliplatin in combination with cetuximab in human colorectal tumor cell lines expressing different level of EGFR.

    Science.gov (United States)

    Balin-Gauthier, Diane; Delord, Jean-Pierre; Rochaix, Philippe; Mallard, Valérie; Thomas, Fabienne; Hennebelle, Isabelle; Bugat, Roland; Canal, Pierre; Allal, Cuider

    2006-06-01

    This study aimed to assess the effect of cetuximab (C225, Erbitux, a chimeric anti-epidermal growth factor receptor (EGFR) monoclonal antibody) in combination with oxaliplatin in vitro and in vivo on four colon cancer cell lines (HCT-8; HT-29, SW620, HCT-116) expressing different levels of EGFR. In vitro, cetuximab combined with oxaliplatin significantly decreased the IC50 values of oxaliplatin in HCT-8 (EGF-R moderate) and HT-29 (EGF-R weak) cell lines, while SW620 (EGF-R negative) and HCT-116 (EGFR strong) cell lines remained unresponsive. This combination was synergistic in HCT-8 and HT-29 cell lines while cetuximab induced no major modification of the IC50 of oxaliplatin in HCT-116 or SW620 cell lines. We then determined the effect of cetuximab on the EGF-induced EGFR phosphorylation and we highlight a correlation between the basal level of phospho-EGFR and the response to the combination. In vivo, the combination of cetuximab plus oxaliplatin significantly inhibited tumor growth of HCT-8 and HT-29 (tumor delay or Td = 21.6+/-2.9 and 18.0+/-2.9 days respectively, synergistic effect) compared to either oxaliplatin (Td=12.6+/-2.3 and 14.4+/-3.2 days respectively) or cetuximab (Td=13.4+/-2.9 and 14.5+/-2.4 days, respectively) alone in xenograft models. The combination had no effect on HCT-116 and SW-620 cell lines. The observed responses are strictly dependent on the cell type, and are not correlated with the level of EGFR expression but related to the basal level of phospho-EGFR. This study provides promising preclinical results for a possible clinical investigation of the combination of oxaliplatin plus cetuximab in chemorefractory colorectal tumors.

  7. Targeting EGFR and COX-2 as a potential treatment improvement strategy in cancer radiotherapy

    International Nuclear Information System (INIS)

    inducible enzyme that is induced by diverse inflammatory stimuli, oncoproteins and growth factors. COX-2 is overexpressed in many types of cancer where it mediates production of prostaglandins, which in turn stimulate tumor growth and protect cells against damage inflicted by cytotoxic agents including radiation. Selective inhibitors of COX-2 affect tumors selectively. Preclinical studies by us and others show that selective COX-2 inhibitors greatly enhance radioresponse of mouse tumors and human tumor xenografts, while they do not appreciably affect normal tissue radioresponse. The mechanisms of radiosensitization include increase in intrinsic radiosensitivity of tumor cells, inhibition of repair from sublethal radiation damage and inhibition of tumor angiogenesis. Both EGFR and COX-2 inhibitors have entered clinical testing in combination with radiotherapy or radiochemotherapy with encouraging initial results

  8. EGFR signaling promotes β-cell proliferation and survivin expression during pregnancy.

    Directory of Open Access Journals (Sweden)

    Elina Hakonen

    Full Text Available Placental lactogen (PL induced serotonergic signaling is essential for gestational β-cell mass expansion. We have previously shown that intact Epidermal growth factor -receptor (EGFR function is a crucial component of this pathway. We now explored more specifically the link between EGFR and pregnancy-induced β-cell mass compensation. Islets were isolated from wild-type and β-cell-specific EGFR-dominant negative mice (E1-DN, stimulated with PL and analyzed for β-cell proliferation and expression of genes involved in gestational β-cell growth. β-cell mass dynamics were analyzed both with traditional morphometrical methods and three-dimensional optical projection tomography (OPT of whole-mount insulin-stained pancreata. Insulin-positive volume analyzed with OPT increased 1.4-fold at gestational day 18.5 (GD18.5 when compared to non-pregnant mice. Number of islets peaked by GD13.5 (680 vs 1134 islets per pancreas, non-pregnant vs. GD13.5. PL stimulated beta cell proliferation in the wild-type islets, whereas the proliferative response was absent in the E1-DN mouse islets. Serotonin synthesizing enzymes were upregulated similarly in both the wild-type and E1-DN mice. However, while survivin (Birc5 mRNA was upregulated 5.5-fold during pregnancy in the wild-type islets, no change was seen in the E1-DN pregnant islets. PL induced survivin expression also in isolated islets and this was blocked by EGFR inhibitor gefitinib, mTOR inhibitor rapamycin and MEK inhibitor PD0325901. Our 3D-volumetric analysis of β-cell mass expansion during murine pregnancy revealed that islet number increases during pregnancy. In addition, our results suggest that EGFR signaling is required for lactogen-induced survivin expression via MAPK and mTOR pathways.

  9. Antisense EGFR sequence enhances apoptosis in a human hepatoma cell line BEL—7404

    Institute of Scientific and Technical Information of China (English)

    FUTAO; HELIU; 等

    1996-01-01

    Effects of antisense epidermal growth factor receptor (EGFR) sequence on apoptotic cell death were examined in a human hepatoma cell line BEL-7404 cells.In the cells of JX-1,a sub clone of BEL-7404 stably transfected with antisense EGFR vector (Cell Research,3:75,1993),an enhanced rate(9.5%) of spontaneous apoptosis was detected by flow cytometry,whereas the rates of spontaneous apoptosis in JX-0 cells,a sub-clone of BEL-7404 transfected by control vector,and the parent BEL-7404 transfected by control vector,and the parent BEL-7404 transfected by control vector,and the parent BEL-7404 cells were almost equal and about 1.7%.Serum-starvation for 72h increased the rate of apoptosis of JX-lcells up to 33.7%,while JX-0 and BEL-7404 cells,under the same condition,produced less than 5% of apoptotic cells.Observation with electron microscope demonstrated that condensation and fragmentation of chromatin and formation of apoptotic bodies often occurred in JX-1 cells,especially during serumstarvation.These results,combined with the data of DNA fragmentation Elisa test,suggested that antisense EGFR sequence enhances apoptosis in the human hepatoma cells.Comparison of intracellular Ca2+ level and the responsiveness of JX-1 cells to the induced action of EGF and tharpsigargin (TG) treatment with that of control JX-0 cells indicated that antisense egfr might interrupt the EGF/EGFR sigaling pathway resulting in the decreass of intracellular Ca2+ pool content as well as the responsiveness of these cells to the extracellular signals.These findings suggest that antisense EGFR either directly or indirectly regulates Ca2+ storage in endoplasmic reticulum,thereby enhances apoptosis in the human hepatoma cells.

  10. EGFR Mutation Status in Uighur Lung Adenocarcinoma Patients

    Directory of Open Access Journals (Sweden)

    Li SHAN

    2013-02-01

    Full Text Available Background and objective Epidermal growth factor receptor (EGFR, a transmembrane protein, is a member of the tyrosine kinase family. Gefitinib, an EGFR tyrosine-kinase inhibitors, has shown a high response rate in the treatment of lung cancer in patients with EGFR mutation. However, significant differences in EGFR mutations exist among different ethnic groups. The aim of this study is to investigate the prevalence of EGFR mutations in Uighur lung adenocarcinoma patients by using a rapid and sensitive detection method and to analyze EGFR mutation differences compared with Han lung adenocarcinoma patients. Methods We examined lung adenocarcinoma tissues from 138 patients, including 68 Uighur lung adenocarcinoma patients and 70 Han lung adenocarcinoma patients, for EGFR mutations in exons 18, 19, 20, and 21 by using the amplification refractory mutation system (ARMS PCR method. The mutation differences between Uighur and Han lung adenocarcinoma were compared by using the chi-square test method. Results EGFR mutations were detected in 43 (31.2% of the 138 lung adenocarcinoma patients. EGFR mutations were detected in 11 (16.2% of the 68 Uighur lung adenocarcinoma patients and in 32 (45.7% of the 70 Han lung adenocarcinoma patients. Significant differences were observed in the EGFR mutations between Uighur lung adenocarcinoma patients and Han lung adenocarcinoma patients (P<0.001. Conclusion Our results indicate that the EGFR mutation in Uighur lung adenocarcinoma patients (16.2% is significantly lower than that in Han lung adenocarcinoma patients (45.7%.

  11. Long-Term Treatment with Erlotinib for EGFR Wild-Type Non-Small Cell Lung Cancer: A Case Report.

    Science.gov (United States)

    Polychronidou, Genovefa; Papakotoulas, Pavlos

    2013-01-01

    The epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) gefitinib and erlotinib are known to have greater efficacy in EGFR mutation-positive non-small cell lung cancer (NSCLC), although erlotinib also has activity in wild-type disease. We report the successful long-term maintenance treatment of a patient with EGFR wild-type NSCLC with gefitinib and later erlotinib. The patient (male; 44 years old; smoker) was diagnosed with EGFR wild-type NSCLC after computer tomography had revealed a mediastinal mass, and histology and mutation testing had identified the tumor as an EGFR wild-type grade 3 adenocarcinoma. The patient received multiple rounds of chemotherapy, followed by gefitinib maintenance (3 years). Later on, he received erlotinib maintenance and developed a persistent rash (grade 1/2) that lasted throughout the treatment. The patient's condition has remained stable on erlotinib for more than 5 years, with no evidence of progression. We describe the patient's disease course and treatment in the context of EGFR TKI therapy and the prognostic factors for long-term clinical outcomes of NSCLC, including the development of erlotinib-induced rash.

  12. Exocyst Sec10 protects renal tubule cells from injury by EGFR/MAPK activation and effects on endocytosis.

    Science.gov (United States)

    Fogelgren, Ben; Zuo, Xiaofeng; Buonato, Janine M; Vasilyev, Aleksandr; Baek, Jeong-In; Choi, Soo Young; Chacon-Heszele, Maria F; Palmyre, Aurélien; Polgar, Noemi; Drummond, Iain; Park, Kwon Moo; Lazzara, Matthew J; Lipschutz, Joshua H

    2014-12-15

    Acute kidney injury is common and has a high mortality rate, and no effective treatment exists other than supportive care. Using cell culture models, we previously demonstrated that exocyst Sec10 overexpression reduced damage to renal tubule cells and speeded recovery and that the protective effect was mediated by higher basal levels of mitogen-activated protein kinase (MAPK) signaling. The exocyst, a highly-conserved eight-protein complex, is known for regulating protein trafficking. Here we show that the exocyst biochemically interacts with the epidermal growth factor receptor (EGFR), which is upstream of MAPK, and Sec10-overexpressing cells express greater levels of phosphorylated (active) ERK, the final step in the MAPK pathway, in response to EGF stimulation. EGFR endocytosis, which has been linked to activation of the MAPK pathway, increases in Sec10-overexpressing cells, and gefitinib, a specific EGFR inhibitor, and Dynasore, a dynamin inhibitor, both reduce EGFR endocytosis. In turn, inhibition of the MAPK pathway reduces ligand-mediated EGFR endocytosis, suggesting a potential feedback of elevated ERK activity on EGFR endocytosis. Gefitinib also decreases MAPK signaling in Sec10-overexpressing cells to levels seen in control cells and, demonstrating a causal role for EGFR, reverses the protective effect of Sec10 overexpression following cell injury in vitro. Finally, using an in vivo zebrafish model of acute kidney injury, morpholino-induced knockdown of sec10 increases renal tubule cell susceptibility to injury. Taken together, these results suggest that the exocyst, acting through EGFR, endocytosis, and the MAPK pathway is a candidate therapeutic target for acute kidney injury.

  13. FIH-1 disrupts an LRRK1/EGFR complex to positively regulate keratinocyte migration.

    Science.gov (United States)

    Peng, Han; Kaplan, Nihal; Yang, Wending; Getsios, Spiro; Lavker, Robert M

    2014-12-01

    Factor inhibiting hypoxia-inducible factor 1 (FIH-1; official symbol HIF1AN) is a hydroxylase that negatively regulates hypoxia-inducible factor 1α but also targets other ankyrin repeat domain-containing proteins such as Notch receptor to limit epithelial differentiation. We show that FIH-1 null mutant mice exhibit delayed wound healing. Importantly, in vitro scratch wound assays demonstrate that the positive role of FIH-1 in migration is independent of Notch signaling, suggesting that this hydroxylase targets another ankyrin repeat domain-containing protein to positively regulate motogenic signaling pathways. Accordingly, FIH-1 increases epidermal growth factor receptor (EGFR) signaling, which in turn enhances keratinocyte migration via mitogen-activated protein kinase pathway, leading to extracellular signal-regulated kinase 1/2 activation. Our studies identify leucine-rich repeat kinase 1 (LRRK1), a key regulator of the EGFR endosomal trafficking and signaling, as an FIH-1 binding partner. Such an interaction prevents the formation of an EGFR/LRRK1 complex, necessary for proper EGFR turnover. The identification of LRRK1 as a novel target for FIH-1 provides new insight into how FIH-1 functions as a positive regulator of epithelial migration.

  14. Activation of the epidermal growth factor receptor (EGFR) by a novel metalloprotease pathway.

    LENUS (Irish Health Repository)

    Bergin, David A

    2008-11-14

    Neutrophil Elastase (NE) is a pro-inflammatory protease present at higher than normal levels in the lung during inflammatory disease. NE regulates IL-8 production from airway epithelial cells and can activate both EGFR and TLR4. TACE\\/ADAM17 has been reported to trans-activate EGFR in response to NE. Here, using 16HBE14o-human bronchial epithelial cells we demonstrate a new mechanism by which NE regulates both of these events. A high molecular weight soluble metalloprotease activity detectable only in supernatants from NE-treated cells by gelatin and casein zymography was confirmed to be meprin alpha by Western immunoblotting. In vitro studies demonstrated the ability of NE to activate meprin alpha, which in turn could release soluble TGFalpha and induce IL-8 production from 16HBE14o- cells. These effects were abrogated by actinonin, a specific meprin inhibitor. NE-induced IL-8 expression was also inhibited by meprin alpha siRNA. Immunoprecipitation studies detected EGFR\\/TLR4 complexes in NE-stimulated cells overexpressing these receptors. Confocal studies confirmed colocalization of EGFR and TLR4 in 16HBE14o- cells stimulated with meprin alpha. NFkappaB was also activated via MyD88 in these cells by meprin alpha. In bronchoalveolar lavage fluid from NE knock-out mice infected intra-tracheally with Pseudomonas aeruginosa meprin alpha was significantly decreased compared with control mice, and was significantly increased and correlated with NE activity, in bronchoalveolar lavage fluid from individuals with cystic fibrosis but not healthy controls. The data describe a previously unidentified lung metalloprotease meprin alpha, and its role in NE-induced EGFR and TLR4 activation and IL-8 production.

  15. Photoprotection by Punica granatum seed oil nanoemulsion entrapping polyphenol-rich ethyl acetate fraction against UVB-induced DNA damage in human keratinocyte (HaCaT) cell line.

    Science.gov (United States)

    Baccarin, Thaisa; Mitjans, Montserrat; Ramos, David; Lemos-Senna, Elenara; Vinardell, Maria Pilar

    2015-12-01

    There has been an increase in the use of botanicals as skin photoprotective agents. Pomegranate (Punica granatum L.) is well known for its high concentration of polyphenolic compounds and for its antioxidant and anti-inflammatory properties. The aim of this study was to analyze the photoprotection provided by P. granatum seed oil nanoemulsion entrapping the polyphenol-rich ethyl acetate fraction against UVB-induced DNA damage in the keratinocyte HaCaT cell line. For this purpose, HaCaT cells were pretreated for 1h with nanoemulsions in a serum-free medium and then irradiated with UVB (90-200 mJ/cm(2)) rays. Fluorescence microscopy analysis provided information about the cellular internalization of the nanodroplets. We also determined the in vitro SPF of the nanoemulsions and evaluated their phototoxicity using the 3T3 Neutral Red Uptake Phototoxicity Test. The nanoemulsions were able to protect the cells' DNA against UVB-induced damage in a concentration dependent manner. Nanodroplets were internalized by the cells but a higher proportion was detected along the cell membrane. The SPF obtained (~25) depended on the concentration of the ethyl acetate fraction and pomegranate seed oil in the nanoemulsion. The photoprotective formulations were classified as non-phototoxic. In conclusion, nanoemulsions entrapping the polyphenol-rich ethyl acetate fraction show potential for use as a sunscreen product. PMID:26406978

  16. Effects of activated fibroblasts on phenotype modulation, EGFR signalling and cell cycle regulation in OSCC cells

    Energy Technology Data Exchange (ETDEWEB)

    Berndt, Alexander, E-mail: alexander.berndt@med.uni-jena.de [Center for Molecular Biomedicine, Institute of Pathology, Jena University Hospital, 07740 Jena (Germany); Büttner, Robert, E-mail: Robert-Buettner@gmx.net [Institute of Biochemistry and Biophysics, Friedrich Schiller University Jena, 07740 Jena (Germany); Gühne, Stefanie, E-mail: stefanie_guehne@gmx.net [Center for Molecular Biomedicine, Institute of Pathology, Jena University Hospital, 07740 Jena (Germany); Gleinig, Anna, E-mail: annagleinig@yahoo.com [Center for Molecular Biomedicine, Institute of Pathology, Jena University Hospital, 07740 Jena (Germany); Richter, Petra, E-mail: P.Richter@med.uni-jena.de [Center for Molecular Biomedicine, Institute of Pathology, Jena University Hospital, 07740 Jena (Germany); Chen, Yuan, E-mail: Yuan.Chen@med.uni-jena.de [Center for Molecular Biomedicine, Institute of Pathology, Jena University Hospital, 07740 Jena (Germany); Franz, Marcus, E-mail: Marcus.Franz@med.uni-jena.de [Clinic of Internal Medicine I, Jena University Hospital, 07740 Jena (Germany); Liebmann, Claus, E-mail: Claus.Liebmann@uni-jena.de [Institute of Biochemistry and Biophysics, Friedrich Schiller University Jena, 07740 Jena (Germany)

    2014-04-01

    Crosstalk between carcinoma associated fibroblasts (CAFs) and oral squamous cell carcinoma (OSCC) cells is suggested to mediate phenotype transition of cancer cells as a prerequisite for tumour progression, to predict patients’ outcome, and to influence the efficacy of EGFR inhibitor therapies. Here we investigate the influence of activated fibroblasts as a model for CAFs on phenotype and EGFR signalling in OSCC cells in vitro. For this, immortalised hTERT-BJ1 fibroblasts were activated with TGFβ1 and PDGFAB to generate a myofibroblast or proliferative phenotype, respectively. Conditioned media (FCM{sub TGF}, FCM{sub PDGF}) were used to stimulate PE/CA-PJ15 OSCC cells. Results were compared to the effect of conditioned media of non-stimulated fibroblasts (FCM{sub B}). FCM{sub TGF} stimulation leads to an up-regulation of vimentin in the OSCC cells and an enhancement of invasive behaviour, indicating EMT-like effects. Similarly, FCM{sub TGF}≫FCM{sub PDGF} induced up-regulation of EGFR, but not of ErbB2/ErbB3. In addition, we detected an increase in basal activities of ERK, PI3K/Akt and Stat3 (FCM{sub TGF}>FCM{sub PDGF}) accompanied by protein interaction of vimentin with pERK. These effects are correlated with an increased proliferation. In summary, our results suggest that the activated myofibroblast phenotype provides soluble factors which are able to induce EMT-like phenomena and to increase EGFR signalling as well as cell proliferation in OSCC cells. Our results indicate a possible influence of activated myofibroblasts on EGFR-inhibitor therapy. Therefore, CAFs may serve as promising novel targets for combined therapy strategies. - Highlights: • A cell culture model for cancer associated fibroblasts is described. • The mutual interaction with OSCC cells leads to up-regulation of EGFR in tumour cells. • mCAF induces EGFR downstream signalling with increased proliferation in OSCC. • Erk activation is associated with protein interaction with vimentin

  17. Suppression of alpha-tocopherol ether-linked acetic acid in VEGF-induced angiogenesis and the possible mechanisms in human umbilical vein endothelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Chuang, Cheng-Hung, E-mail: chchuang@hk.edu.tw [Department of Nutrition, Master Program of Biomedical Nutrition, Hungkuang University, 1018 Sec. 6 Taiwan Boulevard, Taichung 43302, Taiwan, ROC (China); Liu, Chia-Hua [Department of Food Science and Biotechnology, National Chung-Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan, ROC (China); Lu, Ta-Jung [Department of Chemistry, Institute of Technology and Innovation Management, National Chung-Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan, ROC (China); Hu, Miao-Lin, E-mail: mlhuhu@dragon.nchu.edu.tw [Department of Food Science and Biotechnology, National Chung-Hsing University, 250 Kuo Kuang Road, Taichung 40227, Taiwan, ROC (China)

    2014-12-15

    Alpha-tocopherol ether-linked acetic acid (α-TEA) has been reported to exhibit both anti-tumor and anti-metastatic activities in cell culture and animal studies. However, it is unclear whether α-TEA possesses anti-angiogenic effects. In this study, we investigated the effect of α-TEA on vascular endothelial growth factor (VEGF)-induced angiogenesis and matrix metalloproteinase (MMP) expression both in vitro and ex vivo. We found that the α-TEA inhibited tube formation, invasion, and migration in human umbilical vein endothelial cells (HUVECs) and that such actions were accompanied by reduced expression of MMP-2. α-TEA also inhibited ex vivo angiogenesis, as indicated by chicken egg chorioallantoic membrane assay. We further showed that α-TEA attenuated protein expression of VEGF receptor-2 (VEGFR-2)-mediated p38 mitogen-activated protein kinase (p38), phosphorylated p38, and focal adhesion kinase (FAK). Moreover, α-TEA (30 μM) significantly up-regulated protein expression of tissue inhibitors of MMP (TIMP)-2 (by 138%) and the metastasis suppressor gene nm23-H1 (by 54%). These results demonstrate that the anti-angiogenic effect of α-TEA both in vitro and ex vivo and its possible mechanistic action appears to involve the inhibition of MMP-2 level through VEGFR-2-mediated FAK and p38 signaling pathways and through up-regulation of TIMP-2 and nm23-H1 expression. - Graphical abstract: Possible mechanisms of α-TEA on inhibited angiogenesis of human umbilical vein endothelial cells. Brief summary In the present study, we have demonstrated that VEGF-mediated angiogenesis is significantly inhibited by α-TEA, and that this effect involves inhibition of MMP-2 level through VEGFR-2-mediated FAK and p38 signaling pathways related to invasion and migration. - Highlights: • The anti-angiogenic effect and the mechanistic action of α-TEA were investigated. • α-TEA significantly inhibited VEGF-mediated angiogenesis both in vitro and ex vivo. • α-TEA down

  18. Nuclear FABP7 immunoreactivity is preferentially expressed in infiltrative glioma and is associated with poor prognosis in EGFR-overexpressing glioblastoma

    Directory of Open Access Journals (Sweden)

    Aldape Ken D

    2006-04-01

    Full Text Available Abstract Background We previously identified brain type fatty acid-binding protein (FABP7 as a prognostic marker for patients with glioblastoma (GBM. Increased expression of FABP7 is associated with reduced survival. To investigate possible molecular mechanisms underlying this association, we compared the expression and subcellular localization of FABP7 in non-tumor brain tissues with different types of glioma, and examined the expression of FABP7 and epidermal growth factor receptor (EGFR in GBM tumors. Methods Expression of FABP7 in non-tumor brain and glioma specimens was examined using immunohistochemistry, and its correlation to the clinical behavior of the tumors was analyzed. We also analyzed the association between FABP7 and EGFR expression in different sets of GBM specimens using published DNA microarray datasets and semi-quantitative immunohistochemistry. In vitro migration was examined using SF763 glioma cell line. Results FABP7 was present in a unique population of glia in normal human brain, and its expression was increased in a subset of reactive astrocytes. FABP7 immunoreactivity in grade I pilocytic astrocytoma was predominantly cytoplasmic, whereas nuclear FABP7 was detected in other types of infiltrative glioma. Nuclear, not cytoplasmic, FABP7 immunoreactivity was associated with EGFR overexpression in GBM (N = 61, p = 0.008. Expression of the FABP7 gene in GBM also correlated with the abundance of EGFR mRNA in our previous microarray analyses (N = 34, p = 0.016 and an independent public microarray dataset (N = 28, p = 0.03. Compared to those negative for both markers, nuclear FABP7-positive/EGFR-positive and nuclear FABP7-positive/EGFR-negative GBM tumors demonstrated shortest survival, whereas those only positive for EGFR had intermediate survival. EGFR activation increased nuclear FABP7 immunoreactivity in a glioma cell line in vitro, and inhibition of FABP7 expression suppressed EGF-induced glioma-cell migration. Our data

  19. Frequent activation of EGFR in advanced chordomas

    Directory of Open Access Journals (Sweden)

    Dewaele Barbara

    2011-07-01

    Full Text Available Abstract Background Chordomas are rare neoplasms, arising from notochordal remnants in the midline skeletal axis, for which the current treatment is limited to surgery and radiotherapy. Recent reports suggest that receptor tyrosine kinases (RTK might be essential for the survival or proliferation of chordoma cells, providing a rationale for RTK targeted therapy. Nevertheless, the reported data are conflicting, most likely due to the assorted tumor specimens used for the studies and the heterogeneous methodological approaches. In the present study, we performed a comprehensive characterization of this rare entity using a wide range of assays in search for relevant therapeutic targets. Methods Histopathological features of 42 chordoma specimens, 21 primary and 21 advanced, were assessed by immunohistochemistry and fluorescent in situ hybridization (FISH using PDGFRB, CSF1R, and EGFR probes. Twenty-two of these cases, for which frozen material was available (nine primary and 13 advanced tumors, were selectively analyzed using the whole-genome 4.3 K TK-CGH-array, phospho-kinase antibody array or Western immunoblotting. The study was supplemented by direct sequencing of KIT, PDGFRB, CSF1R and EGFR. Results We demonstrated that EGFR is frequently and the most significantly activated RTK in chordomas. Furthermore, concurrent to EGFR activation, the tumors commonly reveal co-activation of alternative RTK. The consistent activation of AKT, the frequent loss of the tumor suppressor PTEN allele, the recurrent activation of upstream RTK and of downstream effectors like p70S6K and mTOR, all indicate the PI3K/AKT pathway as an important mediator of transformation in chordomas. Conclusions Given the complexity of the signaling in chordomas, combined treatment regimens targeting multiple RTK and downstream effectors are likely to be the most effective in these tumors. Personalized therapy with careful selection of the patients, based on the molecular profile of

  20. EGFR-independent autophagy induction with gefitinib and enhancement of its cytotoxic effect by targeting autophagy with clarithromycin in non-small cell lung cancer cells.

    Science.gov (United States)

    Sugita, Shohei; Ito, Kentaro; Yamashiro, Yutaro; Moriya, Shota; Che, Xiao-Fang; Yokoyama, Tomohisa; Hiramoto, Masaki; Miyazawa, Keisuke

    2015-05-22

    Gefitinib (GEF), an inhibitor for EGFR tyrosine kinase, potently induces autophagy in non-small cell lung cancer (NSCLC) cell lines such as PC-9 cells expressing constitutively activated EGFR kinase by EGFR gene mutation as well as A549 and H226 cells with wild-type EGFR. Unexpectedly, GEF-induced autophagy was also observed in non-NSCLC cells such as murine embryonic fibroblasts (MEF) and leukemia cell lines K562 and HL-60 without EGFR expression. Knockout of EGFR gene in A549 cells by CRISPR/Cas9 system still exhibited autophagy induction after treatment with GEF, indicating that the autophagy induction by GEF is not mediated through inhibiting EGFR kinase activity. Combined treatment with GEF and clarithromycin (CAM), a macrolide antibiotic having the effect of inhibiting autophagy flux, enhances the cytotoxic effect in NSCLC cell lines, although treatment with CAM alone exhibits no cytotoxicity. GEF treatment induced up-regulation of endoplasmic reticulum (ER)-stress related genes such as CHOP/GADD153 and GRP78. Knockdown of CHOP in PC-9 cells and Chop-knockout MEF both exhibited less sensitivity to GEF than controls. Addition of CAM in culture medium resulted in further pronounced GEF-induced ER stress loading, while CAM alone exhibited no effect. These data suggest that GEF-induced autophagy functions as cytoprotective and indicates the potential therapeutic possibility of using CAM for GEF therapy. Furthermore, it is suggested that the intracellular signaling for autophagy initiation in response to GEF can be completely dissociated from EGFR, but unknown target molecule(s) of GEF for autophagy induction might exist.

  1. EGFR-independent autophagy induction with gefitinib and enhancement of its cytotoxic effect by targeting autophagy with clarithromycin in non-small cell lung cancer cells.

    Science.gov (United States)

    Sugita, Shohei; Ito, Kentaro; Yamashiro, Yutaro; Moriya, Shota; Che, Xiao-Fang; Yokoyama, Tomohisa; Hiramoto, Masaki; Miyazawa, Keisuke

    2015-05-22

    Gefitinib (GEF), an inhibitor for EGFR tyrosine kinase, potently induces autophagy in non-small cell lung cancer (NSCLC) cell lines such as PC-9 cells expressing constitutively activated EGFR kinase by EGFR gene mutation as well as A549 and H226 cells with wild-type EGFR. Unexpectedly, GEF-induced autophagy was also observed in non-NSCLC cells such as murine embryonic fibroblasts (MEF) and leukemia cell lines K562 and HL-60 without EGFR expression. Knockout of EGFR gene in A549 cells by CRISPR/Cas9 system still exhibited autophagy induction after treatment with GEF, indicating that the autophagy induction by GEF is not mediated through inhibiting EGFR kinase activity. Combined treatment with GEF and clarithromycin (CAM), a macrolide antibiotic having the effect of inhibiting autophagy flux, enhances the cytotoxic effect in NSCLC cell lines, although treatment with CAM alone exhibits no cytotoxicity. GEF treatment induced up-regulation of endoplasmic reticulum (ER)-stress related genes such as CHOP/GADD153 and GRP78. Knockdown of CHOP in PC-9 cells and Chop-knockout MEF both exhibited less sensitivity to GEF than controls. Addition of CAM in culture medium resulted in further pronounced GEF-induced ER stress loading, while CAM alone exhibited no effect. These data suggest that GEF-induced autophagy functions as cytoprotective and indicates the potential therapeutic possibility of using CAM for GEF therapy. Furthermore, it is suggested that the intracellular signaling for autophagy initiation in response to GEF can be completely dissociated from EGFR, but unknown target molecule(s) of GEF for autophagy induction might exist. PMID:25858318

  2. Nuclear EGFR Contributes to Acquired Resistance to Cetuximab

    OpenAIRE

    Li, Chunrong; Iida, Mari; Dunn, Emily F.; Ghia, Amol J.; Wheeler, Deric L

    2009-01-01

    Epidermal growth factor receptor (EGFR) is a ubiquitously expressed receptor tyrosine kinase involved in the etiology of several human cancers. Cetuximab is an EGFR blocking-antibody that has been approved for the treatment of patients with cancers of the head and neck (HNSCC) and metastatic colorectal cancer (mCRC). Previous reports have shown that EGFR translocation to the nucleus is associated with cell proliferation. Here we investigated mechanisms of acquired resistance to cetuximab usin...

  3. EGF‑stimulated AKT activation is mediated by EGFR recycling via an early endocytic pathway in a gefitinib‑resistant human lung cancer cell line.

    Science.gov (United States)

    Nishimura, Yukio; Takiguchi, Soichi; Ito, Shigeru; Itoh, Kazuyuki

    2015-04-01

    EGFR to the plasma membrane induces downstream signaling leading to AKT phosphorylation. Suppression of EGFR membrane recycling by SNX1 appears to be critical for the activation of EGFR/PI3K/AKT signaling pathway in human lung cancer cells.

  4. Nuclear EGFR as a molecular target in cancer

    International Nuclear Information System (INIS)

    The epidermal growth factor receptor (EGFR) has been one of the most targeted receptors in the field of oncology. While anti-EGFR inhibitors have demonstrated clinical success in specific cancers, most patients demonstrate either intrinsic or acquired resistance within one year of treatment. Many mechanisms of resistance to EGFR inhibitors have been identified, one of these being attributed to alternatively localized EGFR from the cell membrane into the cell’s nucleus. Inside the nucleus, EGFR functions as a co-transcription factor for several genes involved in cell proliferation and angiogenesis, and as a tyrosine kinase to activate and stabilize proliferating cell nuclear antigen and DNA dependent protein kinase. Nuclear localized EGFR is highly associated with disease progression, worse overall survival in numerous cancers, and enhanced resistance to radiation, chemotherapy, and the anti-EGFR therapies gefitinib and cetuximab. In this review the current knowledge of how nuclear EGFR enhances resistance to cancer therapeutics is discussed, in addition to highlighting ways to target nuclear EGFR as an anti-cancer strategy in the future

  5. 幽门螺杆菌抑制大鼠乙酸胃溃疡愈合的机制%Mechanism of Helicobacter Pylori Inhibiting the Healing of Acetic Acid-Induced Gastric Ulcer in Rats

    Institute of Scientific and Technical Information of China (English)

    李成军; 夏立丁; 金丽; 王国忠

    2009-01-01

    目的 研究幽门螺杆菌抑制大鼠乙酸胃溃疡愈合的机制.方法 用幽门螺杆菌感染Wistar大鼠,4周后复制出乙酸胃溃疡模型,在溃疡模型复制后的3、8、16天测定胃窦部黏膜G细胞、D细胞的数目、胃液量和pH.结果 Hp+乙酸溃疡组G细胞数目、胃液量高于乙酸溃疡组(P<0.01);D细胞的数目和pH低于乙酸溃疡组(P<0.01).结论 幽门螺杆菌通过增加胃酸分泌抑制溃疡愈合.%Objective To study the mechanism of Helicobacter Pylori inhibiting the healing of acetic acid - induced gastric ulcer in rats. Methods Rats were infected with Helicobacter Pylori and the model of acetic acid gastric ulcer was replicated at 4 weeks after in-fection. Amount of G cell and D cell in mucosa of gastric antrum, quantity of gastric juice and pH were measured at the 3rd,Sth, 16th day after the model was replicated. Results When the group of Hp + acetic acid ulcer compared with the group of acetic acid ulcer, the number of G cell, quantity of gastric juice increased (P < 0.01), and the number of D cell and pH decreased (P < 0.01). Conclusion Helicobacter Pylori inhibits ulcer healing through increasing gastric acid secretion.

  6. Inhibitory Effects of Ethyl Acetate Extract of Andrographis paniculata on NF-κB Trans-Activation Activity and LPS-Induced Acute Inflammation in Mice

    OpenAIRE

    Wen-Wan Chao; Yueh-Hsiung Kuo; Shie-Liang Hsieh; Bi-Fong Lin

    2011-01-01

    This study was to investigate anti-inflammatory effect of Andrographis paniculata (Burm. f.) Nees (Acanthaceae) (AP). The effects of ethyl acetate (EtOAc) extract from AP on the level of inflammatory mediators were examined first using nuclear factor kappa B (NF- κ B) driven luciferase assay. The results showed that AP significantly inhibited NF- κ B luciferase activity and tumor necrosis factor α (TNF- α ), interleukin 6 (IL-6), macrophage inflammatory protein-2 (MIP-2) and nitric oxide (NO)...

  7. Protein phosphorylation profiling using an in situ proximity ligation assay: phosphorylation of AURKA-elicited EGFR-Thr654 and EGFR-Ser1046 in lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Tzu-Chi Chen

    Full Text Available The epidermal growth factor receptor (EGFR, which is up-regulated in lung cancer, involves the activation of mitogenic signals and triggers multiple signaling cascades. To dissect these EGFR cascades, we used 14 different phospho-EGFR antibodies to quantify protein phosphorylation using an in situ proximity ligation assay (in situ PLA. Phosphorylation at EGFR-Thr654 and -Ser1046 was EGF-dependent in the wild-type (WT receptor but EGF-independent in a cell line carrying the EGFR-L858R mutation. Using a ProtoAarray™ containing ∼5000 recombinant proteins on the protein chip, we found that AURKA interacted with the EGFR-L861Q mutant. Moreover, overexpression of EGFR could form a complex with AURKA, and the inhibitors of AURKA and EGFR decreased EGFR-Thr654 and -Ser1046 phosphorylation. Immunohistochemical staining of stage I lung adenocarcinoma tissues demonstrated a positive correlation between AURKA expression and phosphorylation of EGFR at Thr654 and Ser1046 in EGFR-mutant specimens, but not in EGFR-WT specimens. The interplay between EGFR and AURKA provides an explanation for the difference in EGF dependency between EGFR-WT and EGFR-mutant cells and may provide a new therapeutic strategy for lung cancer patients carrying EGFR mutations.

  8. Unravelling the pivotal role of Alix in MVB sorting and silencing of the activated EGFR.

    Science.gov (United States)

    Sun, Sheng; Zhou, Xi; Zhang, Wei; Gallick, Gary E; Kuang, Jian

    2015-03-15

    Endosomal sorting complex required for transport (ESCRT)-III-mediated membrane invagination and scission are a critical step in multivesicular body (MVB) sorting of ubiquitinated membrane receptors, and generally thought to be required for degradation of these receptors in lysosomes. The adaptor protein Alix is critically involved in multiple ESCRT-III-mediated, membrane-remodelling processes in mammalian cells. However, Alix knockdown does not inhibit degradation of the activated epidermal growth factor receptor (EGFR) in mammalian cell lines, leading to a widely held notion that Alix is not critically involved in MVB sorting of ubiquitinated membrane receptors in mammalian cells. In the present study, we demonstrate that, despite its non-essential role in degradation of the activated EGFR, Alix plays a critical role in its MVB sorting and silencing Epidermal growth factor (EGF) stimulation of mammalian cell lines induces Alix's interaction with the ubiquitinated EGFR via the Alix V domain, and increases Alix's association with membrane-bound charged multivesicular body protein 4 (CHMP4) via the Alix Bro1 domain. Under both continuous and pulse-chase EGF stimulation conditions, inhibition of Alix's interaction with membrane-bound CHMP4, inhibition of Alix dimerization through the V domain or Alix knockdown dramatically inhibits MVB sorting of the activated EGFR and promotes sustained activation of extracellular-signal regulated kinase (ERK)1/2. Under the continuous EGF stimulation conditions, these cell treatments also retard degradation of the activated EGFR. These findings indicate that Alix is critically involved in MVB sorting of ubiquitinated membrane receptors in mammalian cells.

  9. EGFR tyrosine kinase inhibitory peptide attenuates Helicobacter pylori-mediated hyper-proliferation in AGS enteric epithelial cells

    International Nuclear Information System (INIS)

    Helicobacter pylori infection is one of the most critical causes of stomach cancer. The current study was conducted to explore the protective effects of an isolated active peptide H-P-6 (Pro-Gln-Pro-Lys-Val-Leu-Asp-Ser) from microbial hydrolysates of Chlamydomonas sp. against H. pylori-induced carcinogenesis. The peptide H-P-6 has effectively suppressed H. pylori-induced hyper-proliferation and migration of gastric epithelial cells (AGS). However, the peptide did not inhibit the viability of the bacteria or invasion into AGS cells. Therefore, the effect of the peptide on regulating H. pylori-induced molecular signaling was investigated. The results indicated that H. pylori activates the EGFR tyrosine kinase signaling and nuclear translocation of the β-catenin. The EGFR activation has led to the up-regulation of PI3K/Akt signaling pathway. Moreover, the nuclear translocation levels of β-catenin were significantly increased as a result of Akt mediated down-regulation of GSK3/β protein levels in the cytoplasm. Both of these consequences have resulted in increased expression of cell survival and migration related genes such as c-Myc, cyclin-D, MMP-2 and matrilysin. Interestingly, the isolated peptide potently inhibited H. pylori-mediated EGFR activation and thereby down-regulated the subsequent P13K/Akt signaling leading to β-catenin nuclear translocation. The effect of the peptide was confirmed with the use of EGFR tyrosine kinase inhibitor AG1487 and molecular docking studies. Collectively this study identifies a potent peptide which regulates the H. pylori-induced hyper-proliferation and migration of AGS cells at molecular level. - Highlights: • Chlamydomonas sp. derived peptide H-P-6 inhibits H. pylori-induced pathogenesis. • H-P-6 suppresses H. pylori-induced hyper-proliferation and migration of AGS cells. • The peptide inhibits H. pylori-induced EGFR activation

  10. Cardiotoxin III suppresses MDA-MB-231 cell metastasis through the inhibition of EGF/EGFR-mediated signaling pathway.

    Science.gov (United States)

    Tsai, Pei-Chien; Hsieh, Chi-Ying; Chiu, Chien-Chih; Wang, Chih-Kuang; Chang, Long-Sen; Lin, Shinne-Ren

    2012-10-01

    Cardiotoxin III (CTX III), a basic polypeptide isolated from Naja naja atra venom, has been shown to exhibit anticancer activity. Epidermal growth factor (EGF) and its receptor, EGFR, play roles in cancer metastasis in various tumors. We use EGF as a metastatic inducer of MDA-MB-231 cells to investigate the effect of CTX III on cell migration. CTX III inhibited the EGF-induced activation of matrix metalloproteinase-9 (MMP-9), and further suppressed cell invasion and migration without obvious cellular cytotoxicity. CTX III suppressed EGF-induced nuclear factor-kappaB (NF-κB) nuclear translocation and also abrogated the EGF-induced phosphorylation of EGFR, phosphatidylinositol 3-kinase (PI3K)/Akt, and extracellular regulated kinase (ERK)1/2. In addition, CTX III similar to wortmannin (a PI3K inhibitor) and U0126 (an up-stream kinase regulating ERK1/2 inhibitor) attenuated cell migration and invasion induced by EGF. Furthermore, the EGFR inhibitor AG1478 inhibited EGF-induced MMP-9 expression, cell migration and invasion, as well as the activation of ERK1/2 and PI3K/Akt, suggesting that ERK1/2 and PI3K/Akt activation occur downstream of EGFR activation. These findings suggest that CTX III inhibited the EGF-induced invasion and migration of MDA-MB-231 cells via EGFR-dependent PI3K/Akt, ERK1/2, and NF-κB signaling, leading to the down-regulation of MMP-9 expression. These results provide a novel mechanism to explain the role of CTX III as a potent anti-metastatic agent in MDA-MB-231 cells.

  11. EGFR tyrosine kinase inhibitory peptide attenuates Helicobacter pylori-mediated hyper-proliferation in AGS enteric epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Himaya, S.W.A. [Marine Bio-Process Research Center, Pukyong National University, Nam-Gu, Busan, 608-737 (Korea, Republic of); Dewapriya, Pradeep [Department of Chemistry, Pukyong National University, Nam-Gu, Busan, 608-737 (Korea, Republic of); Kim, Se-Kwon, E-mail: sknkim@pknu.ac.kr [Marine Bio-Process Research Center, Pukyong National University, Nam-Gu, Busan, 608-737 (Korea, Republic of); Department of Chemistry, Pukyong National University, Nam-Gu, Busan, 608-737 (Korea, Republic of)

    2013-06-15

    Helicobacter pylori infection is one of the most critical causes of stomach cancer. The current study was conducted to explore the protective effects of an isolated active peptide H-P-6 (Pro-Gln-Pro-Lys-Val-Leu-Asp-Ser) from microbial hydrolysates of Chlamydomonas sp. against H. pylori-induced carcinogenesis. The peptide H-P-6 has effectively suppressed H. pylori-induced hyper-proliferation and migration of gastric epithelial cells (AGS). However, the peptide did not inhibit the viability of the bacteria or invasion into AGS cells. Therefore, the effect of the peptide on regulating H. pylori-induced molecular signaling was investigated. The results indicated that H. pylori activates the EGFR tyrosine kinase signaling and nuclear translocation of the β-catenin. The EGFR activation has led to the up-regulation of PI3K/Akt signaling pathway. Moreover, the nuclear translocation levels of β-catenin were significantly increased as a result of Akt mediated down-regulation of GSK3/β protein levels in the cytoplasm. Both of these consequences have resulted in increased expression of cell survival and migration related genes such as c-Myc, cyclin-D, MMP-2 and matrilysin. Interestingly, the isolated peptide potently inhibited H. pylori-mediated EGFR activation and thereby down-regulated the subsequent P13K/Akt signaling leading to β-catenin nuclear translocation. The effect of the peptide was confirmed with the use of EGFR tyrosine kinase inhibitor AG1487 and molecular docking studies. Collectively this study identifies a potent peptide which regulates the H. pylori-induced hyper-proliferation and migration of AGS cells at molecular level. - Highlights: • Chlamydomonas sp. derived peptide H-P-6 inhibits H. pylori-induced pathogenesis. • H-P-6 suppresses H. pylori-induced hyper-proliferation and migration of AGS cells. • The peptide inhibits H. pylori-induced EGFR activation.

  12. Non-Ligand-Induced Dimerization is Sufficient to Initiate the Signalling and Endocytosis of EGF Receptor

    Science.gov (United States)

    Kourouniotis, George; Wang, Yi; Pennock, Steven; Chen, Xinmei; Wang, Zhixiang

    2016-01-01

    The binding of epidermal growth factor (EGF) to EGF receptor (EGFR) stimulates cell mitogenesis and survival through various signalling cascades. EGF also stimulates rapid EGFR endocytosis and its eventual degradation in lysosomes. The immediate events induced by ligand binding include receptor dimerization, activation of intrinsic tyrosine kinase and autophosphorylation. However, in spite of intensified efforts, the results regarding the roles of these events in EGFR signalling and internalization is still very controversial. In this study, we constructed a chimeric EGFR by replacing its extracellular domain with leucine zipper (LZ) and tagged a green fluorescent protein (GFP) at its C-terminus. We showed that the chimeric LZ-EGFR-GFP was constitutively dimerized. The LZ-EGFR-GFP dimer autophosphorylated each of its five well-defined C-terminal tyrosine residues as the ligand-induced EGFR dimer does. Phosphorylated LZ-EGFR-GFP was localized to both the plasma membrane and endosomes, suggesting it is capable of endocytosis. We also showed that LZ-EGFR-GFP activated major signalling proteins including Src homology collagen-like (Shc), extracellular signal-regulated kinase (ERK) and Akt. Moreover, LZ-EGFR-GFP was able to stimulate cell proliferation. These results indicate that non-ligand induced dimerization is sufficient to activate EGFR and initiate cell signalling and EGFR endocytosis. We conclude that receptor dimerization is a critical event in EGF-induced cell signalling and EGFR endocytosis. PMID:27463710

  13. Non-Ligand-Induced Dimerization is Sufficient to Initiate the Signalling and Endocytosis of EGF Receptor

    Directory of Open Access Journals (Sweden)

    George Kourouniotis

    2016-07-01

    Full Text Available The binding of epidermal growth factor (EGF to EGF receptor (EGFR stimulates cell mitogenesis and survival through various signalling cascades. EGF also stimulates rapid EGFR endocytosis and its eventual degradation in lysosomes. The immediate events induced by ligand binding include receptor dimerization, activation of intrinsic tyrosine kinase and autophosphorylation. However, in spite of intensified efforts, the results regarding the roles of these events in EGFR signalling and internalization is still very controversial. In this study, we constructed a chimeric EGFR by replacing its extracellular domain with leucine zipper (LZ and tagged a green fluorescent protein (GFP at its C-terminus. We showed that the chimeric LZ-EGFR-GFP was constitutively dimerized. The LZ-EGFR-GFP dimer autophosphorylated each of its five well-defined C-terminal tyrosine residues as the ligand-induced EGFR dimer does. Phosphorylated LZ-EGFR-GFP was localized to both the plasma membrane and endosomes, suggesting it is capable of endocytosis. We also showed that LZ-EGFR-GFP activated major signalling proteins including Src homology collagen-like (Shc, extracellular signal-regulated kinase (ERK and Akt. Moreover, LZ-EGFR-GFP was able to stimulate cell proliferation. These results indicate that non-ligand induced dimerization is sufficient to activate EGFR and initiate cell signalling and EGFR endocytosis. We conclude that receptor dimerization is a critical event in EGF-induced cell signalling and EGFR endocytosis.

  14. XGFR*, a novel affinity-matured bispecific antibody targeting IGF-1R and EGFR with combined signaling inhibition and enhanced immune activation for the treatment of pancreatic cancer.

    Science.gov (United States)

    Schanzer, Juergen M; Wartha, Katharina; Moessner, Ekkehard; Hosse, Ralf J; Moser, Samuel; Croasdale, Rebecca; Trochanowska, Halina; Shao, Cuiying; Wang, Peng; Shi, Lei; Weinzierl, Tina; Rieder, Natascha; Bacac, Marina; Ries, Carola H; Kettenberger, Hubert; Schlothauer, Tilman; Friess, Thomas; Umana, Pablo; Klein, Christian

    2016-01-01

    The epidermal growth factor receptor (EGFR) and the insulin-like growth factor-1 receptor (IGF-1R) play critical roles in tumor growth, providing a strong rationale for the combined inhibition of IGF-1R and EGFR signaling in cancer therapy. We describe the design, affinity maturation, in vitro and in vivo characterization of the bispecific anti-IGF-1R/EGFR antibody XGFR*. XGFR* is based on the bispecific IgG antibody XGFR, which enabled heterodimerization of an IGF-1R binding scFab heavy chain with an EGFR-binding light and heavy chain by the "knobs-into-holes" technology. XGFR* is optimized for monovalent binding of human EGFR and IGF-1R with increased binding affinity for IGF-1R due to affinity maturation and highly improved protein stability to oxidative and thermal stress. It bears an afucosylated Fc-portion for optimal induction of antibody-dependent cell-mediated cytotoxicity (ADCC). Stable Chinese hamster ovary cell clones with production yields of 2-3 g/L were generated, allowing for large scale production of the bispecific antibody. XGFR* potently inhibits EGFR- and IGF-1R-dependent receptor phosphorylation, reduces tumor cell proliferation in cells with heterogeneous levels of IGF-1R and EGFR receptor expression and induces strong ADCC in vitro. A comparison of pancreatic and colorectal cancer lines demonstrated superior responsiveness to XGFR*-mediated signaling and tumor growth inhibition in pancreatic cancers that frequently show a high degree of IGF-1R/EGFR co-expression. XGFR* showed potent anti-tumoral efficacy in the orthotopic MiaPaCa-2 pancreatic xenograft model, resulting in nearly complete tumor growth inhibition with significant number of tumor remissions. In summary, the bispecific anti-IGF-1R/EGFR antibody XGFR* combines potent signaling and tumor growth inhibition with enhanced ADCC induction and represents a clinical development candidate for the treatment of pancreatic cancer. PMID:26984378

  15. EGFR kinase promotes acquisition of stem cell-like properties: a potential therapeutic target in head and neck squamous cell carcinoma stem cells.

    Directory of Open Access Journals (Sweden)

    Eric L Abhold

    Full Text Available Members of the EGFR/ErbB family of tyrosine kinases are found to be highly expressed and deregulated in many cancers, including head and neck squamous cell carcinoma (HNSCC. The ErbB family, including EGFR, has been demonstrated to play key roles in metastasis, tumorigenesis, cell proliferation, and drug resistance. Recently, these characteristics have been linked to a small subpopulation of cells classified as cancer stem cells (CSCs which are believed to be responsible for tumor initiation and maintenance. In this study, we investigated the possible role of EGFR as a regulator of "stemness" in HNSCC cells. Activation of EGFR by the addition of EGF ligand or ectopic expression of EGFR in two established HNSCC cell lines (UMSCC-22B and HN-1 resulted in the induction of CD44, BMI-1, Oct-4, NANOG, CXCR4, and SDF-1. Activation of EGFR also resulted in increased tumorsphere formation, a characteristic ability of cancer stem cells. Conversely, treatment with the EGFR kinase inhibitor, Gefinitib (Iressa, resulted in decreased expression of the aforementioned genes, and loss of tumorsphere-forming ability. Similar trends were observed in a 99.9% CD44 positive stem cell culture derived from a fresh HNSCC tumor, confirming our findings for the cell lines. Additionally, we found that these putative cancer stem cells, when treated with Gefitinib, possessed a lower capacity to invade and became more sensitive to cisplatin-induced death in vitro. These results suggest that EGFR plays critical roles in the survival, maintenance, and function of cancer stem cells. Drugs that target EGFR, perhaps administered in combination with conventional chemotherapy, might be an effective treatment for HNSCC.

  16. Stimulation of large-conductance calcium-activated potassium channels inhibits neurogenic contraction of human bladder from patients with urinary symptoms and reverses acetic acid-induced bladder hyperactivity in rats.

    Science.gov (United States)

    La Fuente, José M; Fernández, Argentina; Cuevas, Pedro; González-Corrochano, Rocío; Chen, Mao Xiang; Angulo, Javier

    2014-07-15

    We have analysed the effects of large-conductance calcium-activated potassium channel (BK) stimulation on neurogenic and myogenic contraction of human bladder from healthy subjects and patients with urinary symptoms and evaluated the efficacy of activating BK to relief bladder hyperactivity in rats. Bladder specimens were obtained from organ donors and from men with benign prostatic hyperplasia (BPH). Contractions elicited by electrical field stimulation (EFS) and carbachol (CCh) were evaluated in isolated bladder strips. in vivo cystometric recordings were obtained in anesthetized rats under control and acetic acid-induced hyperactive conditions. Neurogenic contractions of human bladder were potentiated by blockade of BK and small-conductance calcium-activated potassium channels (SK) but were unaffected by the blockade of intermediate calcium-activated potassium channels (IK). EFS-induced contractions were inhibited by BK stimulation with NS-8 or NS1619 or by SK/IK stimulation with NS309 (3µM). CCh-induced contractions were not modified by blockade or stimulation of BK, IK or SK. The anti-cholinergic agent, oxybutynin (0.3µM) inhibited either neurogenic or CCh-induced contractions. Neurogenic contractions of bladders from BPH patients were less sensitive to BK inhibition and more sensitive to BK activation than healthy bladders. The BK activator, NS-8 (5mg/kg; i.v.), reversed bladder hyperactivity induced by acetic acid in rats, while oxybutynin was ineffective. NS-8 did not significantly impact blood pressure or heart rate. BK stimulation specifically inhibits neurogenic contractions in patients with urinary symptoms and relieves bladder hyperactivity in vivo without compromising bladder contractile capacity or cardiovascular safety, supporting its potential therapeutic use for relieving bladder overactivity. PMID:24747752

  17. Role for the epidermal growth factor receptor in chemotherapy-induced alopecia.

    Directory of Open Access Journals (Sweden)

    Kyle J Bichsel

    Full Text Available Treatment of cancer patients with chemotherapeutics like cyclophosphamide often causes alopecia as a result of premature and aberrant catagen. Because the epidermal growth factor receptor (EGFR signals anagen hair follicles to enter catagen, we hypothesized that EGFR signaling may be involved in cyclophosphamide-induced alopecia. To test this hypothesis, skin-targeted Egfr mutant mice were generated by crossing floxed Egfr and Keratin 14 promoter-driven Cre recombinase mice. Cyclophosphamide treatment of control mice resulted in alopecia while Egfr mutant skin was resistant to cyclophosphamide-induced alopecia. Egfr mutant skin entered catagen normally, as indicated by dermal papilla condensation and decreased follicular proliferation, but did not progress to telogen as did Egfr wild type follicles. Egfr mutant follicles responded with less proliferation, apoptosis, and fewer p53-positive cells after cyclophosphamide. Treatment of control mice with the EGFR inhibitors erlotinib or gefitinib similarly suppressed alopecia and catagen progression by cyclophosphamide. Secondary analysis of clinical trials utilizing EGFR-targeted therapies and alopecia-inducing chemotherapy also revealed evidence for involvement of EGFR in chemotherapy-induced alopecia. Taken together, our results demonstrated the involvement of EGFR signaling in chemotherapy-induced alopecia, which will help in the design of novel therapeutic regimens to minimize chemotherapy-induced alopecia.

  18. System N transporters are critical for glutamine release and modulate metabolic fluxes of glucose and acetate in cultured cortical astrocytes: changes induced by ammonia.

    Science.gov (United States)

    Zielińska, Magdalena; Dąbrowska, Katarzyna; Hadera, Mussie Ghezu; Sonnewald, Ursula; Albrecht, Jan

    2016-01-01

    Glutamine (Gln) is synthesized in astrocytes from glutamate (Glu) and ammonia, whereupon it can be released to be transferred to neurons. This study evaluated the as yet not definitely established role of the astrocytic Gln transporters SN1 and SN2 (Slc38a3 and Slc38a5 respectively) in Gln release and metabolic fluxes of glucose and acetate, the canonical precursors of Glu. Cultured neocortical astrocytes were grown in the absence or presence of ammonia (5 mM NH4 Cl, 24 h), which deregulates astrocytic metabolism in hyperammonemic encephalopathies. HPLC analyses of cell extracts of SN1/SN2 siRNA-treated (SN1/SN2-) astrocytes revealed a ~ 3.5-fold increase in Gln content and doubling of glutathione, aspartate, alanine and glutamate contents, as compared to SN1/SN2+ astrocytes. Uptake and efflux of preloaded [(3) H]Gln was likewise significantly decreased in SN1/SN2- astrocytes. The atom percent excess (13) C values (given as M + 1) for alanine, aspartate and glutamate were decreased when the SN1/SN2- cells were incubated with [1-(13) C] glucose, while Gln consumption was not changed. No difference was seen in M + 1 values in SN1/SN2- cells incubated with [2-(13) C] acetate, which were not treated with ammonia. In SN1/SN2- astrocytes, the increase in Gln content and the decrease in radiolabeled Gln release upon exposure to ammonia were found abrogated, and glutamate labeling from [2-(13) C]acetate was decreased as compared to SN1/SN2+ astrocytes. The results underscore a profound role of SN1 and/or SN2 in Gln release from astrocytes under physiological conditions, but less so in ammonia-overexposed astrocytes, and appear to manifest dependence of astrocytic glucose metabolism to Glu/Gln on unimpaired SN1/SN2- mediated Gln release from astrocytes. The astrocytic N system transporters SN1 and SN2 show preponderance to mediate glutamine (Gln) efflux. Under hyperammonemic conditions, accumulation of Gln, a direct product of ammonia detoxification, may deregulate

  19. Detecting and treating breast cancer resistance to EGFR inhibitors

    Science.gov (United States)

    Moonlee, Sun-Young; Bissell, Mina J.; Furuta, Saori; Meier, Roland; Kenny, Paraic A.

    2016-04-05

    The application describes therapeutic compositions and methods for treating cancer. For example, therapeutic compositions and methods related to inhibition of FAM83A (family with sequence similarity 83) are provided. The application also describes methods for diagnosing cancer resistance to EGFR inhibitors. For example, a method of diagnosing cancer resistance to EGFR inhibitors by detecting increased FAM83A levels is described.

  20. DNA methylation down-regulates EGFR expression in chicken

    Science.gov (United States)

    The epidermal growth factor receptor (EGFR), a growth-factor-receptor tyrosine kinase, was found up-regulated in numerous tumors, which provides a good target for cancer therapy. Although it was documented that oncoviruses are responsible for the activation of EGFR in tumors, the impact of Marek’s d...

  1. IGFBP2 potentiates nuclear EGFR-STAT3 signaling

    Science.gov (United States)

    Chua, Corrine Yingxuan; Liu, Yuexin; Granberg, Kirsi J.; Hu, Limei; Haapasalo, Hannu; Annala, Matti J.; Cogdell, David E.; Verploegen, Maartje; Moore, Lynette M.; Fuller, Gregory N.; Nykter, Matti; Cavenee, Webster K.; Zhang, Wei

    2015-01-01

    Insulin-like growth factor binding protein 2 (IGFBP2) is a pleiotropic oncogenic protein that has both extracellular and intracellular functions. Despite a clear causal role in cancer development, the tumor-promoting mechanisms of IGFBP2 are poorly understood. The contributions of intracellular IGFBP2 to tumor development and progression are also unclear. Here we present evidence that both exogenous IGFBP2 treatment and cellular IGFBP2 overexpression lead to aberrant activation of EGFR, which subsequently activates STAT3 signaling. Furthermore, we demonstrate that IGFBP2 augments the nuclear accumulation of EGFR to potentiate STAT3 transactivation activities, via activation of the nuclear EGFR signaling pathway. Nuclear IGFBP2 directly influences the invasive and migratory capacities of human glioblastoma cells, providing a direct link between intracellular (and particularly nuclear) IGFBP2 and cancer hallmarks. These activities are also consistent with the strong association between IGFBP2 and STAT3-activated genes derived from the TCGA database for human glioma. A high level of all 3 proteins (IGFBP2, EGFR and STAT3) was strongly correlated with poorer survival in an independent patient dataset. These results identify a novel tumor-promoting function for IGFBP2 of activating EGFR/STAT3 signaling and facilitating EGFR accumulation in the nucleus, thereby deregulating EGFR signaling by 2 distinct mechanisms. As targeting EGFR in glioma has been relatively unsuccessful, this study suggests that IGFBP2 may be a novel therapeutic target. PMID:25893308

  2. IGFBP2 potentiates nuclear EGFR-STAT3 signaling.

    Science.gov (United States)

    Chua, C Y; Liu, Y; Granberg, K J; Hu, L; Haapasalo, H; Annala, M J; Cogdell, D E; Verploegen, M; Moore, L M; Fuller, G N; Nykter, M; Cavenee, W K; Zhang, W

    2016-02-11

    Insulin-like growth factor binding protein 2 (IGFBP2) is a pleiotropic oncogenic protein that has both extracellular and intracellular functions. Despite a clear causal role in cancer development, the tumor-promoting mechanisms of IGFBP2 are poorly understood. The contributions of intracellular IGFBP2 to tumor development and progression are also unclear. Here we present evidence that both exogenous IGFBP2 treatment and cellular IGFBP2 overexpression lead to aberrant activation of epidermal growth factor receptor (EGFR), which subsequently activates signal transducer and activator of transcription factor 3 (STAT3) signaling. Furthermore, we demonstrate that IGFBP2 augments the nuclear accumulation of EGFR to potentiate STAT3 transactivation activities, via activation of the nuclear EGFR signaling pathway. Nuclear IGFBP2 directly influences the invasive and migratory capacities of human glioblastoma cells, providing a direct link between intracellular (and particularly nuclear) IGFBP2 and cancer hallmarks. These activities are also consistent with the strong association between IGFBP2 and STAT3-activated genes derived from The Cancer Genome Atlas database for human glioma. A high level of all three proteins (IGFBP2, EGFR and STAT3) was strongly correlated with poorer survival in an independent patient data set. These results identify a novel tumor-promoting function for IGFBP2 of activating EGFR/STAT3 signaling and facilitating EGFR accumulation in the nucleus, thereby deregulating EGFR signaling by two distinct mechanisms. As targeting EGFR in glioma has been relatively unsuccessful, this study suggests that IGFBP2 may be a novel therapeutic target.

  3. A Novel Technique to Detect EGFR Mutations in Lung Cancer

    Directory of Open Access Journals (Sweden)

    Yuanbin Liu

    2016-05-01

    Full Text Available Epidermal growth factor receptor (EGFR gene mutations occur in multiple human cancers; therefore, the detection of EGFR mutations could lead to early cancer diagnosis. This study describes a novel EGFR mutation detection technique. Compared to direct DNA sequencing detection methods, this method is based on allele-specific amplification (ASA, recombinase polymerase amplification (RPA, peptide nucleic acid (PNA, and SYBR Green I (SYBR, referred to as the AS-RPA-PNA-SYBR (ARPS system. The principle of this technique is based on three continuous steps: ASA or ASA combined with PNA to prevent non-target sequence amplification (even single nucleotide polymorphisms, SNPs, the rapid amplification advantage of RPA, and appropriate SYBR Green I detection (the samples harboring EGFR mutations show a green signal. Using this method, the EGFR 19Del(2 mutation was detected in 5 min, while the EGFR L858R mutation was detected in 10 min. In this study, the detection of EGFR mutations in clinical samples using the ARPS system was compatible with that determined by polymerase chain reaction (PCR and DNA sequencing methods. Thus, this newly developed methodology that uses the ARPS system with appropriate primer sets is a rapid, reliable, and practical way to assess EGFR mutations in clinical samples.

  4. A Novel Technique to Detect EGFR Mutations in Lung Cancer

    Science.gov (United States)

    Liu, Yuanbin; Lei, Ting; Liu, Zhiyu; Kuang, Yanbin; Lyu, Jianxin; Wang, Qi

    2016-01-01

    Epidermal growth factor receptor (EGFR) gene mutations occur in multiple human cancers; therefore, the detection of EGFR mutations could lead to early cancer diagnosis. This study describes a novel EGFR mutation detection technique. Compared to direct DNA sequencing detection methods, this method is based on allele-specific amplification (ASA), recombinase polymerase amplification (RPA), peptide nucleic acid (PNA), and SYBR Green I (SYBR), referred to as the AS-RPA-PNA-SYBR (ARPS) system. The principle of this technique is based on three continuous steps: ASA or ASA combined with PNA to prevent non-target sequence amplification (even single nucleotide polymorphisms, SNPs), the rapid amplification advantage of RPA, and appropriate SYBR Green I detection (the samples harboring EGFR mutations show a green signal). Using this method, the EGFR 19Del(2) mutation was detected in 5 min, while the EGFR L858R mutation was detected in 10 min. In this study, the detection of EGFR mutations in clinical samples using the ARPS system was compatible with that determined by polymerase chain reaction (PCR) and DNA sequencing methods. Thus, this newly developed methodology that uses the ARPS system with appropriate primer sets is a rapid, reliable, and practical way to assess EGFR mutations in clinical samples. PMID:27223277

  5. Lupeol evokes anticancer effects in oral squamous cell carcinoma by inhibiting oncogenic EGFR pathway.

    Science.gov (United States)

    Rauth, Sanchita; Ray, Sudipta; Bhattacharyya, Sayantan; Mehrotra, Debapriya Ghosh; Alam, Neyaz; Mondal, Goutam; Nath, Partha; Roy, Asoke; Biswas, Jaydip; Murmu, Nabendu

    2016-06-01

    Epidermal growth factor receptor (EGFR) pathway is overexpressed in head and neck cancer (HNC). Lupeol, a natural triterpene (phytosterol found in fruits, vegetables, etc.), has been reported to be effective against multiple cancer indications. Here we investigate the antitumor effects of Lupeol and underlying mechanism in oral cancer. Lupeol-induced antitumor response was evaluated in two oral squamous cell carcinoma (OSCC) cell lines (UPCI:SCC131 and UPCI:SCC084) by viability (MTT), proliferation, and colony formation assays. Lupeol-mediated induction of apoptosis was examined by caspase 3/7 assay and flow cytometry. Effect of Lupeol on EGFR in the presence or absence of EGF was delineated by Western blot. The mRNA stability assay was performed to check the role of Lupeol on COX-2 mRNA regulation. Lupeol inhibited proliferation of OSCC cells in vitro by inducing apoptosis 48 h post treatment. Ligand-induced phosphorylation of EGFR and subsequent activation of its downstream molecules such as protein kinase B (PKB or AKT), I kappa B (IκB), and nuclear factor kappa B (NF-κB) was also found to be, in part, suppressed. Interestingly, Lupeol suppressed expression of COX-2 at mRNA and protein level in a time-dependent manner. Primary explants from oral squamous cell carcinoma tissues further confirmed significant inhibition of proliferation (Ki67) in Lupeol-treated explants as compared to untreated control at 48 h. Together these data suggest that Lupeol may act as a potent inhibitor of the EGFR signaling in OSCC and therefore imply its role in triggering antitumor efficacy. PMID:27206736

  6. Study of the mechanism on the apoptosis induced in Human leukemia cell line K562 by the combination of indole-3-acetic acid and horseradish peroxidase

    Institute of Scientific and Technical Information of China (English)

    宋土生; 杨玲; 黄辰; 刘利英; 倪磊; 王爱英; 罗禹

    2007-01-01

    Indole-3-acetic acid(IAA)is an i mportant typeof the plant growth hor mone found in higherplants,and participate inthe regulation of plant celldivision,elongation and differentiation.It is pres-ent in human urine,blood plas ma and central nerv-ous system.IAAis well tolerated in human and isnot oxidized by mammalian peroxidase.Recent re-searches suggest that the combination of IAA andhorseradish peroxidase(HRP)is cytotoxic to mam-malian cells,and could be used as a novel cancertherapy[1-3],while neither IAAn...

  7. EGFR and microvessel density in canine malignant mammary tumours.

    Science.gov (United States)

    Carvalho, Maria Isabel; Guimarães, Maria João; Pires, Isabel; Prada, Justina; Silva-Carvalho, Ricardo; Lopes, Carlos; Queiroga, Felisbina L

    2013-12-01

    The epidermal growth factor receptor (EGFR) is a transmembrane tyrosine kinase receptor which has been shown to have an important role in human breast cancer. Its role appears to be associated with increased angiogenesis and metastasis. In order to clarify its role in canine mammary tumours (CMT), 61 malignant neoplasms were studied by using immunohistochemistry, comparing expression of EGFR, microvessel density (MVD) by CD31 immunolabelling and characteristics of tumour aggressiveness. High EGFR immunoexpression was statistically significantly associated with tumour size, tumour necrosis, mitotic grade, histological grade of malignancy and clinical stage. High CD31 immunoreactivity was statistically significantly associated with tubule formation, histological grade of malignancy and clinical stage. A positive correlation between EGFR and CD31 immunoexpression (r = 0.843; P aggression in malignant CMT, presenting the possibility of using EGFR inhibitors in the context of metastatic disease treatment. PMID:24091029

  8. Therapeutic Effect of Oridonin Tablet on Acetic Acid-induced Ulcerative Colitis in Mice%冬凌草甲素片对醋酸诱导的小鼠溃疡性结肠炎的治疗作用

    Institute of Scientific and Technical Information of China (English)

    臧凯宏; 杜丽东; 刘晓梅; 马骏; 任远

    2012-01-01

    目的 考察冬凌草甲素片口服给药对醋酸诱导的小鼠溃疡性结肠炎的治疗作用.方法 醋酸诱导的溃疡性结肠炎小鼠分别给予不同剂量的冬凌草甲素片灌胃给药,给药7d后,考察冬凌草甲素片对溃疡性结肠炎小鼠病变活动(体质量、便潜血及粪便性状)的影响,以及对结肠病理组织学变化,结肠髓过氧化物酶活性及胸腺和脾脏指数的影响.结果 冬凌草甲素片口服给药可剂量依赖性的降低结肠炎小鼠的病变活动、减轻结肠炎症、降低髓过氧化物酶活性,改善免疫器官脏器指数,以冬凌草甲素片高剂量给药组的作用更为显著.结论 高剂量冬凌草甲素片口服给药对醋酸诱导的小鼠溃疡性结肠炎具有治疗作用,其机制可能与冬凌草甲素的抗炎和免疫调节作用有关.%OBJECTIVE To investigate the therapeutic effect of Oridonin tablet on acetic acid-induced ulcerative colitis in mice.METHODS Oridonin tablets at different dosages were administered orally to acetic acid-induced colitis mice.After 7 days of treatment,the effects of Oridonin tablet on disease activity (i.e.body weight,stool blood,and stool consistency),colonic macroscopic and histological score,myleoperoxidase activity,and thymic and splenic indexes were evaluated in acetic acid-induced ulcerative colitis in mice.RESULTS Oridonin tablet treatment dose-dependently reduced the disease activity,attenuated colonic inflammation and myleoperoxidase activity,and improved the thymic and splenic indexes in acetic acid-induced ulcerative colitis in mice,especially in high dose of Oridonin tablet treated group.CONCLUSION High dose of Oridonin tablet treatment shows therapeutic effect on acetic acid-induced ulcerative colitis in mice,the underlying mechanism may have close correlation with its anti-inflammatory and immune regulatory effects.

  9. Adamantane-1-ammonium acetate

    Directory of Open Access Journals (Sweden)

    Elise J. C. de Vries

    2011-06-01

    Full Text Available In the title compound, C10H18N+·C2H3O2−, the ammonium H atoms of the cation are linked to three acetate anions via N—H...O hydrogen bonds, forming a chain structure extending along the b axis.

  10. Low prevalence of K-RAS, EGF-R and BRAF mutations in sinonasal adenocarcinomas. Implications for anti-EGFR treatments.

    Science.gov (United States)

    Franchi, Alessandro; Innocenti, Duccio Rossi Degli; Palomba, Annarita; Miligi, Lucia; Paiar, Fabiola; Franzese, Ciro; Santucci, Marco

    2014-07-01

    We have previously shown that a subset of sinonasal intestinal-type adenocarcinomas (ITAC) shows activation of the epidermal growth factor-receptor (EGFR) pathway. In this study we examine the status of the EGFR, KRAS and BRAF genes in a series of sinonasal intestinal (ITAC) and non-intestinal type adenocarcinomas (non-ITAC). Eighteen ITACs and 12 non-ITACs were studied immunohistochemically for EGFR expression. Point mutations were analyzed for EGFR exons 19 and 21, KRAS exon 2 and BRAF exon 15 by direct sequencing. Non-ITACs showed significantly higher expression of EGFR (p = 0.015). Mutation analysis revealed one ITAC with EGFR and one ITAC with KRAS mutation, while two non-ITACs presented mutation of BRAF. We conclude that a subset of sinonasal adenocarcinomas shows overexpression of EGFR, while activating mutations of the signaling cascade downstream of EGFR are rare, suggesting that these tumors could be good candidates for anti-EGFR therapies.

  11. EGFR soluble isoforms and their transcripts are expressed in meningiomas.

    Science.gov (United States)

    Guillaudeau, Angélique; Durand, Karine; Bessette, Barbara; Chaunavel, Alain; Pommepuy, Isabelle; Projetti, Fabrice; Robert, Sandrine; Caire, François; Rabinovitch-Chable, Hélène; Labrousse, François

    2012-01-01

    The EGFR (epidermal growth factor receptor) is involved in the oncogenesis of many tumors. In addition to the full-length EGFR (isoform a), normal and tumor cells produce soluble EGFR isoforms (sEGFR) that lack the intracellular domain. sEGFR isoforms b, c and d are encoded by EGFR variants 2 (v2), 3 (v3) and 4 (v4) mRNA resulting from gene alternative splicing. Accordingly, the results of EGFR protein expression analysis depend on the domain targeted by the antibodies. In meningiomas, EGFR expression investigations mainly focused on EGFR isoform a. sEGFR and EGFRvIII mutant, that encodes a constitutively active truncated receptor, have not been studied. In a 69 meningiomas series, protein expression was analyzed by immunohistochemistry using extracellular domain targeted antibody (ECD-Ab) and intracellular domain targeted antibody (ICD-Ab). EGFRv1 to v4 and EGFRvIII mRNAs were quantified by RT-PCR and EGFR amplification revealed by MLPA. Results were analyzed with respect to clinical data, tumor resection (Simpson grade), histological type, tumor grade, and patient outcome.Immunochemical staining was stronger with ECD-Ab than with ICD-Ab. Meningiomas expressed EGFRv1 to -v4 mRNAs but not EGFRvIII mutant. Intermediate or high ECD-Ab staining and high EGFRv1 to v4 mRNA levels were associated to a better progression free survival (PFS). PFS was also improved in women, when tumor resection was evaluated as Simpson 1 or 2, in grade I vs. grade II and III meningiomas and when Ki67 labeling index was lower than 10%. Our results suggest that, EGFR protein isoforms without ICD and their corresponding mRNA variants are expressed in meningiomas in addition to the whole isoform a. EGFRvIII was not expressed. High expression levels seem to be related to a better prognosis. These results indicate that the oncogenetic mechanisms involving the EGFR pathway in meningiomas could be different from other tumor types. PMID:22623992

  12. EGFR soluble isoforms and their transcripts are expressed in meningiomas.

    Directory of Open Access Journals (Sweden)

    Angélique Guillaudeau

    Full Text Available The EGFR (epidermal growth factor receptor is involved in the oncogenesis of many tumors. In addition to the full-length EGFR (isoform a, normal and tumor cells produce soluble EGFR isoforms (sEGFR that lack the intracellular domain. sEGFR isoforms b, c and d are encoded by EGFR variants 2 (v2, 3 (v3 and 4 (v4 mRNA resulting from gene alternative splicing. Accordingly, the results of EGFR protein expression analysis depend on the domain targeted by the antibodies. In meningiomas, EGFR expression investigations mainly focused on EGFR isoform a. sEGFR and EGFRvIII mutant, that encodes a constitutively active truncated receptor, have not been studied. In a 69 meningiomas series, protein expression was analyzed by immunohistochemistry using extracellular domain targeted antibody (ECD-Ab and intracellular domain targeted antibody (ICD-Ab. EGFRv1 to v4 and EGFRvIII mRNAs were quantified by RT-PCR and EGFR amplification revealed by MLPA. Results were analyzed with respect to clinical data, tumor resection (Simpson grade, histological type, tumor grade, and patient outcome.Immunochemical staining was stronger with ECD-Ab than with ICD-Ab. Meningiomas expressed EGFRv1 to -v4 mRNAs but not EGFRvIII mutant. Intermediate or high ECD-Ab staining and high EGFRv1 to v4 mRNA levels were associated to a better progression free survival (PFS. PFS was also improved in women, when tumor resection was evaluated as Simpson 1 or 2, in grade I vs. grade II and III meningiomas and when Ki67 labeling index was lower than 10%. Our results suggest that, EGFR protein isoforms without ICD and their corresponding mRNA variants are expressed in meningiomas in addition to the whole isoform a. EGFRvIII was not expressed. High expression levels seem to be related to a better prognosis. These results indicate that the oncogenetic mechanisms involving the EGFR pathway in meningiomas could be different from other tumor types.

  13. Epidermal Growth Factor Receptor (EGFR) mutation analysis, gene expression profiling and EGFR protein expression in primary prostate cancer

    International Nuclear Information System (INIS)

    Activating mutations of the epidermal growth factor receptor (EGFR) confer sensitivity to the tyrosine kinase inhibitors (TKi), gefitinib and erlotinib. We analysed EGFR expression, EGFR mutation status and gene expression profiles of prostate cancer (PC) to supply a rationale for EGFR targeted therapies in this disease. Mutational analysis of EGFR TK domain (exons from 18 to 21) and immunohistochemistry for EGFR were performed on tumour tissues derived from radical prostatectomy from 100 PC patients. Gene expression profiling using oligo-microarrays was also carried out in 51 of the PC samples. EGFR protein overexpression (EGFRhigh) was found in 36% of the tumour samples, and mutations were found in 13% of samples. Patients with EGFRhigh tumours experienced a significantly increased risk of biochemical relapse (hazard ratio-HR 2.52, p=0.02) compared with patients with tumours expressing low levels of EGFR (EGFRlow). Microarray analysis did not reveal any differences in gene expression between EGFRhigh and EGFRlow tumours. Conversely, in EGFRhigh tumours, we were able to identify a 79 gene signature distinguishing mutated from non-mutated tumours. Additionally, 29 genes were found to be differentially expressed between mutated/EGFRhigh (n=3) and mutated/EGFRlow tumours (n=5). Four of the down-regulated genes, U19/EAF2, ABCC4, KLK3 and ANXA3 and one of the up-regulated genes, FOXC1, are involved in PC progression. Based on our findings, we hypothesize that accurate definition of the EGFR status could improve prognostic stratification and we suggest a possible role for EGFR-directed therapies in PC patients. Having been generated in a relatively small sample of patients, our results warrant confirmation in larger series

  14. 表皮生长因子受体抑制剂耐药机制的研究进展%Research Progress of Mechanism of Resistance to EGFR Inhibitors

    Institute of Scientific and Technical Information of China (English)

    冯昌怡

    2012-01-01

    The epidermal growth factor receptor( EGFR )is an important molecular target in cancer treatment, and two classes of anti-EGFR agents, the monoclonal antibodies and the small molecular tyro-sine kinase inhibitors,have developed in clinical successfully. Howeverthe primary and secondary resistance to anti-EGFR agents have been paid increasing attention. The mechanisms of resistance to EGFR inhibitors in solid tumors may include:EGFR,K-ras,Braf mutations;autocrine/paracrine production of lig-and;MET amplification; constitutive activation of a downstream pathway; activation of alternative pathways; activation of EGFR-independent, tumour-induced angiogenesis and etc. .%表皮生长因子受体(EGFR)是抗肿瘤治疗中重要的分子靶点,两类抗表皮生长因子受体(anti-EGFR)药物:单克隆抗体及小分子酪氨酸激酶抑制剂已成功应用于临床,但其原发和继发耐药问题也日益受到关注.肿瘤对anti-EGFR药物耐药的可能机制包括:EGFR、K-ras、Braf突变;配体的自分泌或旁分泌;原癌基因MET扩增;下游通路持续活化;激活替代通路;肿瘤诱导不依赖于EGFR活化的血管生成等.

  15. Synergistic anti-proliferative and pro-apoptotic activity of combined therapy with bortezomib, a proteasome inhibitor, with anti-epidermal growth factor receptor (EGFR) drugs in human cancer cells.

    Science.gov (United States)

    Cascone, Tina; Morelli, Maria Pia; Morgillo, Floriana; Kim, Woo-Young; Rodolico, Gabriella; Pepe, Stefano; Tortora, Giampaolo; Berrino, Liberato; Lee, Ho-Young; Heymach, John V; Ciardiello, Fortunato

    2008-09-01

    The proteasome plays a pivotal role in the turnover of regulatory transduction proteins induced by activated cell membrane growth factor receptors. The epidermal growth factor receptor (EGFR) pathway is crucial in the development and progression of human epithelial cancers. Proteasome inhibition may sensitize human cancer cell lines to EGFR inhibitors. We investigated the growth inhibitory and pro-apoptotic effects of the proteasome inhibitor bortezomib in combination with anti-EGFR drugs, such as gefitinib, vandetanib, and cetuximab in EGFR-expressing human cancer cell lines. Bortezomib determined dose-dependent growth inhibition in a nine cancer cell line panel (IC(50) values, range 6-42 nM). A significant synergistic growth inhibitory effect was observed with the combination of bortezomib and each EGFR inhibitor in all cell lines (combination index, CI, range 0.10-0.55), which was accompanied by a significant induction in apoptosis by the combined treatment with bortezomib, cetuximab and vandetanib. In HCT-116 colon cancer and A549 lung adenocarcinoma cells, bortezomib plus EGFR inhibitor treatment induced a more effective inhibition of EGFR-activated down-stream signals, including a marked suppression in activated, phosphorylated Akt (P-Akt). In contrast, overexpression of a constitutively active P-Akt protected A549 cells by cell growth inhibition and apoptosis following treatment with bortezomib and EGFR inhibitors. The combined treatment with bortezomib and EGFR inhibitors has a synergistic growth inhibitory and pro-apoptotic activity in different human cancer cells which possess a functional EGFR-dependent autocrine growth pathway through to a more efficient and sustained inhibition of Akt.

  16. On the nanotoxicity of PAMAM dendrimers: Superfect® stimulates the EGFR-ERK1/2 signal transduction pathway via an oxidative stress-dependent mechanism in HEK 293 cells.

    Science.gov (United States)

    Akhtar, Saghir; Chandrasekhar, Bindu; Attur, Sreeja; Yousif, Mariam H M; Benter, Ibrahim F

    2013-05-01

    Polyamidoamine (PAMAM) dendrimers are cationic branch-like macromolecules that may serve as drug delivery systems for gene-based therapies such as RNA interference. For their safe use in the clinic, they should ideally only enhance drug delivery to target tissues and exhibit no adverse effects. However, little is known about their toxicological profiles in terms of their interactions with cellular signal transduction pathways such as the epidermal growth factor receptor (EGFR). The EGFR is an important signaling cascade that regulates cell growth, differentiation, migration, survival and apoptosis. Here, we investigated the impact of naked, unmodified Superfect (SF), a commercially available generation 6 PAMAM dendrimer, on the epidermal growth factor receptor (EGFR) tyrosine kinase-extracellular-regulated kinase 1/2 (ERK1/2) signaling pathway in human embryonic kidney (HEK 293) cells. At concentrations routinely used for transfection, SF exhibited time and dose-dependent stimulation of EGFR and ERK1/2 phosphorylation whereas AG1478, a selective EGFR tyrosine kinase antagonist, inhibited EGFR-ERK1/2 signaling. SF-induced phosphorylation of EGFR for 1h was partly reversible upon removal of the dendrimer and examination of cells 24 later. Co-treatment of SF with epidermal growth factor (EGF) ligand resulted in greater EGFR stimulation than either agent alone implying that the stimulatory effects of SF and the ligand are synergistic. Dendrimer-induced stimulation of EGFR-ERK1/2 signaling could be attenuated by the antioxidants apocynin, catalase and tempol implying that an oxidative stress dependent mechanism was involved. These results show for the first time that PAMAM dendrimers, aside from their ability to improve drug delivery, can modulate the important EGFR-ERK1/2 cellular signal transduction pathway - a novel finding that may have a bearing on their safe application as drug delivery systems.

  17. Colon-specific delivery of a probiotic-derived soluble protein ameliorates intestinal inflammation in mice through an EGFR-dependent mechanism.

    Science.gov (United States)

    Yan, Fang; Cao, Hanwei; Cover, Timothy L; Washington, M Kay; Shi, Yan; Liu, LinShu; Chaturvedi, Rupesh; Peek, Richard M; Wilson, Keith T; Polk, D Brent

    2011-06-01

    Probiotic bacteria can potentially have beneficial effects on the clinical course of several intestinal disorders, but our understanding of probiotic action is limited. We have identified a probiotic bacteria-derived soluble protein, p40, from Lactobacillus rhamnosus GG (LGG), which prevents cytokine-induced apoptosis in intestinal epithelial cells. In the current study, we analyzed the mechanisms by which p40 regulates cellular responses in intestinal epithelial cells and p40's effects on experimental colitis using mouse models. We show that the recombinant p40 protein activated EGFR, leading to Akt activation. Activation of EGFR by p40 was required for inhibition of cytokine-induced apoptosis in intestinal epithelial cells in vitro and ex vivo. Furthermore, we developed a pectin/zein hydrogel bead system to specifically deliver p40 to the mouse colon, which activated EGFR in colon epithelial cells. Administration of p40-containing beads reduced intestinal epithelial apoptosis and disruption of barrier function in the colon epithelium in an EGFR-dependent manner, thereby preventing and treating DSS-induced intestinal injury and acute colitis. Furthermore, p40 activation of EGFR was required for ameliorating colon epithelial cell apoptosis and chronic inflammation in oxazolone-induced colitis. These data define what we believe to be a previously unrecognized mechanism of probiotic-derived soluble proteins in protecting the intestine from injury and inflammation.

  18. EGFR Amplification and Glioblastoma Stem-Like Cells

    Directory of Open Access Journals (Sweden)

    Katrin Liffers

    2015-01-01

    Full Text Available Glioblastoma (GBM, the most common malignant brain tumor in adults, contains a subpopulation of cells with a stem-like phenotype (GS-cells. GS-cells can be maintained in vitro using serum-free medium supplemented with epidermal growth factor, basic fibroblast growth factor-2, and heparin. However, this method does not conserve amplification of the Epidermal Growth Factor Receptor (EGFR gene, which is present in over 50% of all newly diagnosed GBM cases. GS-cells with retained EGFR amplification could overcome the limitations of current in vitro model systems and contribute significantly to preclinical research on EGFR-targeted therapy. This review recapitulates recent methodological approaches to expand stem-like cells from GBM with different EGFR status in order to maintain EGFR-dependent intratumoral heterogeneity in vitro. Further, it will summarize the current knowledge about the impact of EGFR amplification and overexpression on the stem-like phenotype of GBM-derived GS-cells and different approaches to target the EGFR-dependent GS-cell compartment of GBM.

  19. Cellular Functions Regulated by Phosphorylation of EGFR on Tyr845

    Directory of Open Access Journals (Sweden)

    Ken-ichi Sato

    2013-05-01

    Full Text Available The Src gene product (Src and the epidermal growth factor receptor (EGFR are prototypes of oncogene products and function primarily as a cytoplasmic non-receptor tyrosine kinase and a transmembrane receptor tyrosine kinase, respectively. The identification of Src and EGFR, and the subsequent extensive investigations of these proteins have long provided cutting edge research in cancer and other molecular and cellular biological studies. In 1995, we reported that the human epidermoid carcinoma cells, A431, contain a small fraction of Src and EGFR in which these two kinase were in physical association with each other, and that Src phosphorylates EGFR on tyrosine 845 (Y845 in the Src-EGFR complex. Y845 of EGFR is located in the activation segment of the kinase domain, where many protein kinases contain kinase-activating autophosphorylation sites (e.g., cAMP-dependent protein kinase, Src family kinases, transmembrane receptor type tyrosine kinases or trans-phosphorylation sites (e.g., cyclin-dependent protein kinase, mitogen-activated protein kinase, Akt protein kinase. A number of studies have demonstrated that Y845 phosphorylation serves an important role in cancer as well as normal cells. Here we compile the experimental facts involving Src phosphorylation of EGFR on Y845, by which cell proliferation, cell cycle control, mitochondrial regulation of cell metabolism, gamete activation and other cellular functions are regulated. We also discuss the physiological relevance, as well as structural insights of the Y845 phosphorylation.

  20. Nuclear EGFR contributes to acquired resistance to cetuximab.

    Science.gov (United States)

    Li, C; Iida, M; Dunn, E F; Ghia, A J; Wheeler, D L

    2009-10-29

    Epidermal growth factor receptor (EGFR) is a ubiquitously expressed receptor tyrosine kinase involved in the etiology of several human cancers. Cetuximab is an EGFR-blocking antibody that has been approved for the treatment of patients with head and neck squamous cell carcinoma and metastatic colorectal cancer. Previous reports have shown that EGFR translocation to the nucleus is associated with cell proliferation. Here we investigated mechanisms of acquired resistance to cetuximab using a model derived from the non-small cell lung cancer line H226. We demonstrated that cetuximab-resistant cells overexpress HER family ligands including epidermal growth factor (EGF), amphiregulin, heparin-binding EGF and beta-cellulin. Overexpression of these ligands is associated with the nuclear translocation of the EGFR and this process was mediated by the Src family kinases (SFK). Treatment of cetuximab-resistant cells with the SFK inhibitor, dasatinib, resulted in loss of nuclear EGFR, increased membrane expression of the EGFR and resensitization to cetuximab. In addition, expression of a nuclear localization sequence-tagged EGFR in cetuximab-sensitive cells increased resistance to cetuximab both in vitro and in mouse xenografts. Collectively, these data suggest that nuclear expression of EGFR may be an important molecular determinant of resistance to cetuximab therapy and provides a rationale for investigating nuclear EGFR as a biomarker for cetuximab response. Further, these data suggest a rationale for the design of clinical trials that examine the value of treating patients with cetuximab-resistant tumors with inhibitors of SFKs in combination with cetuximab. PMID:19684613

  1. The anti-EGFR antibody cetuximab sensitizes human head and neck squamous cell carcinoma cells to radiation in part through inhibiting radiation-induced upregulation of HIF-1α

    OpenAIRE

    Lu, Haiquan; Liang, Ke; Lu, Yang; Fan, Zhen

    2012-01-01

    In this study, we investigated the mechanisms underlying cetuximab-mediated radiosensitization of HNSCC. Irradiation of HNSCC cells upregulated hypoxia-inducible factor-1 alpha (HIF-1α) via a mechanism involving de novo synthesis of HIF-1α protein. Radiation-induced upregulation of HIF-1α was completely abolished by concurrent treatment of HNSCC cells with cetuximab. Experimental elevation of constitutively expressed HIF-1α abolished cetuximab-mediated radiosensitization in HNSCC cells, where...

  2. Acetate Kinase Isozymes Confer Robustness in Acetate Metabolism

    DEFF Research Database (Denmark)

    Chan, Siu Hung Joshua; Nørregaard, Lasse; Solem, Christian;

    2014-01-01

    Acetate kinase (ACK) (EC no: 2.7.2.1) interconverts acetyl-phosphate and acetate to either catabolize or synthesize acetyl-CoA dependent on the metabolic requirement. Among all ACK entries available in UniProt, we found that around 45% are multiple ACKs in some organisms including more than 300...... physiological roles in L. lactis to maintain a robust acetate metabolism for fast growth at different extracellular acetate concentrations. The existence of ACK isozymes may reflect a common evolutionary strategy in bacteria in an environment with varying concentrations of acetate....

  3. Antibiofilm Properties of Acetic Acid

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Alhede, Morten; Jensen, Peter Østrup;

    2014-01-01

    -negative biofilms using acetic acid both as a liquid and as a dry salt. In addition, we present our clinical experience of acetic acid treatment of chronic wounds. In conclusion, we here present the first comprehensive in vitro and in vivo testing of acetic acid against bacterial biofilms....

  4. Deoxycholic acid mediates non-canonical EGFR-MAPK activation through the induction of calcium signaling in colon cancer cells.

    Science.gov (United States)

    Centuori, Sara M; Gomes, Cecil J; Trujillo, Jesse; Borg, Jamie; Brownlee, Joshua; Putnam, Charles W; Martinez, Jesse D

    2016-07-01

    Obesity and a western diet have been linked to high levels of bile acids and the development of colon cancer. Specifically, increased levels of the bile acid deoxycholic acid (DCA), an established tumor promoter, has been shown to correlate with increased development of colorectal adenomas and progression to carcinoma. Herein we investigate the mechanism by which DCA leads to EGFR-MAPK activation, a candidate mechanism by which DCA may promote colorectal tumorigenesis. DCA treated colon cancer cells exhibited strong and prolonged activation of ERK1/2 when compared to EGF treatment alone. We also showed that DCA treatment prevents EGFR degradation as opposed to the canonical EGFR recycling observed with EGF treatment. Moreover, the combination of DCA and EGF treatment displayed synergistic activity, suggesting DCA activates MAPK signaling in a non-canonical manner. Further evaluation showed that DCA treatment increased intracellular calcium levels and CAMKII phosphorylation, and that blocking calcium with BAPTA-AM abrogated MAPK activation induced by DCA, but not by EGF. Finally we showed that DCA-induced CAMKII leads to MAPK activation through the recruitment of c-Src. Taken together, we demonstrated that DCA regulates MAPK activation through calcium signaling, an alternative mechanism not previously recognized in human colon cancer cells. Importantly, this mechanism allows for EGFR to escape degradation and thus achieve a constitutively active state, which may explain its tumor promoting effects.

  5. Preparing Process of Cerium Acetate and Rare Earth Acetate

    Institute of Scientific and Technical Information of China (English)

    Qiao Jun; Ma Ying; Xu Yanhui; Zhang Jun; Chang Shu; Hao Xianku

    2004-01-01

    Preparing process was presented and the influences of concentration of acetic acid, reaction temperature, the ratio of cerium carbonate and acetic acid, heat preservation time to the yield of cerium acetate were discussed.The crystalline cerium acetate and rare earth acetate such as ( La, Ce, Pr, Nd) (Ac) 3, ( Ce, Pr, Nd) (Ac) 3, ( Pr, Nd, Er,Y) (Ac) 3 and yttrium acetate were prepared under this condition.The shape, structure and composition of the crystals were determined by the methods of SEM, TG-DTA, X-ray diffraction and chemical analysis.The optimum prepared conditions of cerium acetate were described.This prepared process has characteristics such as simple process route, low cost, high yield, good quality, no pollution to environment, etc.

  6. EGFR/cell membrane chromatography-online-high performance liquid chromatography/mass spectrometry method for screening EGFR antagonists from Radix Angelicae Pubescentis

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The intracellular kinase domains of the epidermal growth factor receptor(EGFR) in some tumor cells are significant targets for drug discovery.We have developed a new EGFR cell membrane chromatography(EGFR/CMC)-online-high performance liquid chromatography/mass spectrometry(HPLC/MS) method for screening anti-EGFR antagonists from medicinal herbs such as Radix Angelicae Pubescentis.In this study,the HEK293 EGFR cells with high expression of EGFR were used to prepare cell membrane stationary phase(CMSP) in the EGFR/CMC model.The retention fractions on the EGFR/CMC model were directly analyzed by combining a 10 port columns switcher with a HPLC/MS system online.As a result,osthole from Radix Angelicae Pubescentis was found to be the active component acting on EGFR like dasatinib as the control drug.There was a good relationship between their inhibiting effects on EGFR secretion and HEK293 EGFR cell growth in vitro.This new EGFR/CMC-online-HPLC/MS method can be applied for screening anti-EGFR antagonists from TCMs,for instance,Radix Angelicae Pubescentis.It will be a useful method for drug discovery with natural medicinal herbs as a leading compound resource.

  7. Progress of EGFR Mutation and EGFR-targeted Therapy%EGFR基因突变与肿瘤靶向治疗

    Institute of Scientific and Technical Information of China (English)

    薛丽; 白玉杰

    2012-01-01

    表皮生长因子受体(epidermal growth factor receptor,EGFR)属于受体酪氨酸激酶超家族,在多种恶性肿瘤中表达.配体与EGFR结合诱导形成二聚体和构象变化,活化酪氨酸激酶及信号转导途径,产生细胞增殖、侵润、转移及抗凋亡等效应.EGFR酪氨酸激酶抑制剂(tyrosine kinase inhibitors,TKIs)类靶向药物,如吉非替尼和厄洛替尼等已应用于临床.临床研究显示仅10%~30%患者对TKIs敏感,部分位于EGFR激酶结构域的活化突变与药物敏感性相关.检测EGFR基因突变有助于预测对药物敏感性和提高疗效.随着治疗绝大多数敏感的患者获得继发耐药性,其中约半数有继发突变T790M,降低药物对靶分子的亲和力,其他许多位于EGFR下游信号途径或旁激活途径的分子也参与耐药形成.因此,未来个体化用药和准确预测敏感性,不仅仅要分析EGFR基因,而且要综合考虑下游和其他信号途径的基因,如PI3K,K-RAS,BRAF,MET和PTEN等.%The epidermal growth factor receptor(EGFR) belongs to the super-family of receptor tyrosine kinase and is expressed in many malignancies. Upon their ligand-induced dimerization and conformational change, it initiates activation of intracellular tyrosine kinase and a vast array of cell signaling pathways. The cascade of intracellular activation results in cell proliferation, invasion, metastasis and decreased apoptosis. EGFR represents a critical player in many types of malignancies and becomes a natural goal of the targeted therapy. Both monoclonal antibodies and tyrosine kinase inhibitors (TKIs), such as erlotinib and gefitinib, have already entered clinical application. Clinical trials have shown that only 10%-30% of patients responded to the TKIs treatment. Further studies have found that some mutations within the kinase domain activated the kinase and conferred sensitivity to the treatments. The detection of mutations will likely predict the sensitive patients and

  8. Management of EGFR-inhibitor associated rash: a retrospective study in 49 patients

    Directory of Open Access Journals (Sweden)

    Gerber Peter

    2012-02-01

    Full Text Available Abstract Background In recent years inhibitors directed against the epidermal growth factor receptor (EGFR have evolved as effective targeting cancer drugs. Characteristic papulopustular exanthemas, often described as acneiform rashes, are the most frequent adverse effect associated with this class of novel cancer drugs and develop in > 90% of patients. Notably, the rash may significantly compromise the patients' quality of life, thereby potentially leading to incompliance as well as dose reduction or even termination of the anti-EGFR therapy. Yet, an effective dermatologic management of cutaneous adverse effects can be achieved. Whereas various case reports, case series or expert opinions on the management of EGFR-inhibitor (EGFRI induced rashes have been published, data on systematic management studies are sparse. Methods Here, we present a retrospective, uncontrolled, comparative study in 49 patients on three established regimens for the management of EGFRI-associated rashes. Results Strikingly, patients' rash severity improved significantly over three weeks of treatment with topical mometason furoate cream, topical prednicarbate cream plus nadifloxacin cream, as well as topical prednicarbate cream plus nadifloxacin cream plus systemic isotretinoin. Conclusions In summary our results demonstrate that EGFRI-associated rashes can be effectively managed by specific dermatologic interventions. Whereas mild to moderate rashes should be treated with basic measures in combination with topical glucocorticosteroids or combined regiments using glucocorticosteroids and antiseptics/antibiotics, more severe or therapy-resistant rashes are likely to respond with the addition of systemic retinoids.

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

    International Nuclear Information System (INIS)

    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

  10. 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.

  11. Effects of EGFR Gene Polymorphisms on Efficacy and Prognosis 
in Advanced Non-small Cell Lung Cancer Treated with EGFR-TKIs

    Directory of Open Access Journals (Sweden)

    Liangshan DA

    2013-03-01

    Full Text Available An increasing number of patients with advanced non-small cell lung cancer (NSCLC have been treated with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs. However, significant differences in response to EGFR-TKIs have been shown among advanced NSCLC patients. Recently, selection of patients was mainly based on EGFR gene mutation detection. Nevertheless, mutation detection is often limited by tumour tissues derivation, technique complexity, high cost, and so on. It is urgent to seek other biological markers to predict efficacy of EGFR-TKIs. Many studies have founded that the EGFR gene polymorphisms are also associated with clinical outcome and prognosis in treatment of advanced NSCLC with EGFR-TKIs. Here, we presented a review discussing the correlation between EGFR gene polymorphisms and the efficacy of EGFR-TKIs in advanced NSCLC.

  12. Changes in sebum levels and the development of acneiform rash in patients with non–small cell lung cancer after treatment with EGFR inhibitors

    Directory of Open Access Journals (Sweden)

    Nakahara T

    2015-01-01

    Full Text Available Takeshi Nakahara,1,2 Yoichi Moroi,2 Koichi Takayama,3 Eriko Itoh,1,2 Makiko Kido-Nakahara,2 Yoichi Nakanishi,3 Masutaka Furue2 1Division of Skin Surface Sensing, 2Department of Dermatology, 3Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan Background: It has recently been shown that patients treated with epidermal growth factor receptor (EGFR inhibitors often develop various cutaneous adverse events. While the pathogenesis underlying these events remains unclear, the relationship between skin toxicity induced by EGFR inhibitors and the sebaceous glands that express EGFR has been previously reported. Objectives: The primary aim of this study was to determine the relationship between cutaneous sebum levels and acneiform rash, a typical skin toxicity of EGFR inhibitors, by measuring the sebum levels before and after EGFR inhibitor treatment. Methods: Eight patients diagnosed with non–small cell lung cancer (NSCLC (three men and five women with an average age of 69.3 years who were initiated on treatment with EGFR inhibitors (either gefitinib [Iressa®] or erlotinib [Tarceva®] were enrolled. Using a Sebumeter®, sebum levels in the face, chest, and back of each patient were measured before and after EGFR inhibitor treatment. The development of acneiform rash in each skin region was also assessed. Results: Changes in sebum level along with the development of an acneiform rash were observed after patients were started on EGFR inhibitor treatment. Patients who developed an EGFR inhibitor–induced acneiform rash tended to have higher pretreatment sebum levels (baseline than did patients who did not experience an acneiform rash. At each time point measurement, sebum levels were found to be significantly higher in patients who had developed an acneiform rash at that time. Patients who developed rash during treatment showed greater differences in sebum level compared with

  13. Radiolabeled Cetuximab Conjugates for EGFR Targeted Cancer Diagnostics and Therapy

    OpenAIRE

    Wiebke Sihver; Jens Pietzsch; Mechthild Krause; Michael Baumann; Jörg Steinbach; Hans-Jürgen Pietzsch

    2014-01-01

    The epidermal growth factor receptor (EGFR) has evolved over years into a main molecular target for the treatment of different cancer entities. In this regard, the anti-EGFR antibody cetuximab has been approved alone or in combination with: (a) chemotherapy for treatment of colorectal and head and neck squamous cell carcinoma and (b) with external radiotherapy for treatment of head and neck squamous cell carcinoma. The conjugation of radionuclides to cetuximab in combination with the specif...

  14. Detection and Evaluation of EGFR Mutation Status in Serum of Patients with Advanced Non-small Cell Lung Cancer Treated with EGFR-TKIs

    Directory of Open Access Journals (Sweden)

    Ling MA

    2013-06-01

    Full Text Available Background and objective Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs has shown a high response rate in the treatment of lung cancer in patients with (EGFR mutation. The aim of this study is to evaluate the relationship between EGFR mutation status in serum and predicting benefit from EGFR-TKIs therapy in patients with advanced non-small cell lung cancer (NSCLC. Methods We examined EGFR mutation status in serum of 80 patients with advanced, EGFR-TKIs given as first-line therapy NSCLC. All patients were received long-term follow-up, and the drug efficacy were observed and evaluated. Results The EGFR mutation in serum was detected in 33.8% (27/80 of NSCLC patients examined, in which exon 19 deletion mutation was present at a frequency of 44.4% (12/27 and exon 21 point mutation was 55.6% (15/27; The response rate to EGFR-TKI in patients with EGFR mutation in serum was (55.6%, 15/27, which was remarkably higher than that in EGFR wild-type patients (17.0%, 9/53, the difference was statistically significant (χ2=0.370, P<0.001; The median progression free survival (PFS of patients with EGFR mutation in serum was remarkably better than that of EGFR wild-type patients (9.8 months vs 5.7 months, P=0.014. Conclusion In patients with advanced, EGFR-positive in serum NSCLC, EGFR-TKIs given as first-line therapy is associated with improved drug efficacy. The results suggest that it is feasible to use serum to detect EGFR mutation, which can predict a benefit from EGFR-TKIs given as first-line therapy.

  15. EGFR signaling in colorectal cancer: a clinical perspective

    Directory of Open Access Journals (Sweden)

    Saletti P

    2015-01-01

    Full Text Available Piercarlo Saletti,1 Francesca Molinari,2 Sara De Dosso,1 Milo Frattini2 1Oncology Institute of Southern Switzerland, Bellinzona, 2Laboratory of Molecular Pathology, Institute of Pathology, Locarno, Switzerland Abstract: Colorectal cancer (CRC remains a formidable health burden worldwide, with up to 50% of patients developing metastases during the course of their disease. This group of CRC patients, characterized by the worst prognosis, has been extensively investigated to improve their life expectancy. Main efforts, focused on the epidermal growth-factor receptor (EGFR, which plays a pivotal role in CRC pathogenesis, have led to the development and introduction in clinical practice of specific targeted therapies (ie, monoclonal antibodies. Subsequently, the scientific community has tried to identify molecular predictors of the efficacy of such therapies. However, it has become clear that EGFR alterations occurring in CRC are difficult to investigate, and therefore their predictive role is unclear. In contrast, the clinical role of two downstream members (KRAS and NRAS has been clearly demonstrated. Currently, EGFR-targeted therapies can be administered only to patients with wild-type KRAS and NRAS genes. Our review addresses the medical management of metastatic CRC. Specifically, we describe in detail the molecular biology of metastatic CRC, focusing on the EGFR signaling pathway, and we discuss the role of current and emerging related biomarkers and therapies in this field. We also summarize the clinical evidence regarding anti-EGFR monoclonal antibodies and examine potential future perspectives. Keywords: colorectal cancer, EGFR, gene mutations, cetuximab, panitumumab

  16. 4-Carbamoylpiperidinium acetate monohydrate

    Directory of Open Access Journals (Sweden)

    Urs D. Wermuth

    2010-12-01

    Full Text Available In the structure of the title compound, C6H13N2O+·C2H3O2−·H2O, the amide H atoms of the cations form centrosymmetric cyclic hydrogen-bonding associations incorporating two water molecules [graph set R42(8], which are conjoint with cyclic water-bridged amide–amide associations [R44(12] and larger R44(20 associations involving the water molecule and the acetate anions, which bridge through the piperidinium H-bond donors, giving an overall three-dimensional framework structure.

  17. Luteolin suppresses development of medroxyprogesterone acetate-accelerated 7,12-dimethylbenz(a)anthracene-induced mammary tumors in Sprague-Dawley rats.

    Science.gov (United States)

    Cook, Matthew T; Mafuvadze, Benford; Besch-Williford, Cynthia; Ellersieck, Mark R; Goyette, Sandy; Hyder, Salman M

    2016-02-01

    Postmenopausal women undergoing hormone-replacement therapy containing both progestins and estrogens are at an increased risk of developing breast cancer compared with women taking estrogen alone. We recently demonstrated that medroxyprogesterone acetate, a progestin commonly used for hormone-replacement therapy, accelerates development of mammary carcinogenesis in 7,12-dimethylbenz(a)anthracene‑treated Sprague-Dawley rats. Synthetic antiprogestins used to block the deleterious effects of progestins, are themselves associated with toxic side-effects. In order to circumvent this, we used the aforementioned model to identify less toxic natural compounds that may prevent the development of progestin-accelerated tumors. Luteolin, a naturally-occurring flavonoid commonly found in fruits and vegetables, has previously been shown to possess anticancer properties. In our studies, both low (1 mg/kg) and high (25 mg/kg) doses of luteolin significantly suppressed progestin-dependent increases in tumor incidence, while increasing tumor latency and reducing the occurrence of large (>300 mm3) mammary tumors. However, an intermediate dose of luteolin (10 mg/kg), while suppressing the development of large tumors, did not affect either tumor incidence or latency. Immunohistochemical analysis of tumor tissues revealed that all concentrations of luteolin (1, 10, and 25 mg/kg) significantly reduced levels of VEGF within tumors. The suppressive effects of luteolin on tumor incidence and volume, together with its ability to reduce VEGF and blood vessels, persisted even after treatment was terminated. This suggests that luteolin possesses anti‑angiogenic properties which could mechanistically explain its capacity to control tumor progression. Thus luteolin may be a valuable, non-toxic, naturally-occurring anticancer compound which may potentially be used to combat progestin-accelerated mammary tumors. PMID:26719029

  18. Genetic link between Cabeza, a Drosophila homologue of Fused in Sarcoma (FUS), and the EGFR signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Shimamura, Mai; Kyotani, Akane [Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan); Insect Biomedical Research Center, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan); Azuma, Yumiko [Department of Neurology, Kyoto Prefectural University of Medicine, 465 Kajii-cho,Kamigyo-ku, Kyoto 602-8566 (Japan); Yoshida, Hideki; Binh Nguyen, Thanh [Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan); Insect Biomedical Research Center, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan); Mizuta, Ikuko; Yoshida, Tomokatsu; Mizuno, Toshiki [Department of Neurology, Kyoto Prefectural University of Medicine, 465 Kajii-cho,Kamigyo-ku, Kyoto 602-8566 (Japan); Nakagawa, Masanori [North Medical Center, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyo-ku, Kyoto 602-8566 (Japan); Tokuda, Takahiko, E-mail: ttokuda@koto.kpu-m.ac.jp [Department of Neurology, Kyoto Prefectural University of Medicine, 465 Kajii-cho,Kamigyo-ku, Kyoto 602-8566 (Japan); Department of Molecular Pathobiology of Brain Diseases, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyo-ku, Kyoto 602-8566 (Japan); Yamaguchi, Masamitsu, E-mail: myamaguc@kit.ac.jp [Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan); Insect Biomedical Research Center, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan)

    2014-08-01

    Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease that causes progressive muscular weakness. Fused in Sarcoma (FUS) that has been identified in familial ALS is an RNA binding protein that is normally localized in the nucleus. However, its function in vivo is not fully understood. Drosophila has Cabeza (Caz) as a FUS homologue and specific knockdown of Caz in the eye imaginal disc and pupal retina using a GMR-GAL4 driver was here found to induce an abnormal morphology of the adult compound eyes, a rough eye phenotype. This was partially suppressed by expression of the apoptosis inhibitor P35. Knockdown of Caz exerted no apparent effect on differentiation of photoreceptor cells. However, immunostaining with an antibody to Cut that marks cone cells revealed fusion of these and ommatidia of pupal retinae. These results indicate that Caz knockdown induces apoptosis and also inhibits differentiation of cone cells, resulting in abnormal eye morphology in adults. Mutation in EGFR pathway-related genes, such as rhomboid-1, rhomboid-3 and mirror suppressed the rough eye phenotype induced by Caz knockdown. Moreover, the rhomboid-1 mutation rescued the fusion of cone cells and ommatidia observed in Caz knockdown flies. The results suggest that Caz negatively regulates the EGFR signaling pathway required for determination of cone cell fate in Drosophila. - Highlights: • Knockdown of Cabeza induced rough eye phenotype. • Knockdown of Cabeza induced fusion of cone cells in pupal retinae. • Knockdown of Cabeza induced apoptosis in pupal retinae. • Mutation in EGFR pathway-related genes suppressed the rough eye phenotype. • Cabeza may negatively regulate the EGFR pathway.

  19. Antiproliferative effect of growth hormone-releasing hormone (GHRH antagonist on ovarian cancer cells through the EGFR-Akt pathway

    Directory of Open Access Journals (Sweden)

    Varga Jozsef

    2010-05-01

    Full Text Available Abstract Background Antagonists of growth hormone-releasing hormone (GHRH are being developed for the treatment of various human cancers. Methods MTT assay was used to test the proliferation of SKOV3 and CaOV3. The splice variant expression of GHRH receptors was examined by RT-PCR. The expression of protein in signal pathway was examined by Western blotting. siRNA was used to block the effect of EGFR. Results In this study, we investigated the effects of a new GHRH antagonist JMR-132, in ovarian cancer cell lines SKOV3 and CaOV3 expressing splice variant (SV1 of GHRH receptors. MTT assay showed that JMR-132 had strong antiproliferative effects on SKOV3 and CaOV3 cells in both a time-dependent and dose-dependent fashion. JMR-132 also induced the activation and increased cleaved caspase3 in a time- and dose-dependent manner in both cell lines. In addition, JMR-132 treatments decreased significantly the epidermal growth factor receptor (EGFR level and the phosphorylation of Akt (p-Akt, suggesting that JMR-132 inhibits the EGFR-Akt pathway in ovarian cancer cells. More importantly, treatment of SKOV3 and CaOV3 cells with 100 nM JMR-132 attenuated proliferation and the antiapoptotic effect induced by EGF in both cell lines. After the knockdown of the expression of EGFR by siRNA, the antiproliferative effect of JMR-132 was abolished in SKOV3 and CaOV3 cells. Conclusions The present study demonstrates that the inhibitory effect of the GHRH antagonist JMR-132 on proliferation is due, in part, to an interference with the EGFR-Akt pathway in ovarian cancer cells.

  20. Antitumor and antiangiogenic effect of the dual EGFR and HER-2 tyrosine kinase inhibitor lapatinib in a lung cancer model

    Directory of Open Access Journals (Sweden)

    Collantes Maria

    2010-05-01

    Full Text Available Abstract Background There is strong evidence demonstrating that activation of epidermal growth factor receptors (EGFRs leads to tumor growth, progression, invasion and metastasis. Erlotinib and gefitinib, two EGFR-targeted agents, have been shown to be relevant drugs for lung cancer treatment. Recent studies demonstrate that lapatinib, a dual tyrosine kinase inhibitor of EGFR and HER-2 receptors, is clinically effective against HER-2-overexpressing metastatic breast cancer. In this report, we investigated the activity of lapatinib against non-small cell lung cancer (NSCLC. Methods We selected the lung cancer cell line A549, which harbors genomic amplification of EGFR and HER-2. Proliferation, cell cycle analysis, clonogenic assays, and signaling cascade analyses (by western blot were performed in vitro. In vivo experiments with A549 cells xenotransplanted into nude mice treated with lapatinib (with or without radiotherapy were also carried out. Results Lapatinib dramatically reduced cell proliferation (P P P in vitro. Furthermore, lapatinib induced G1 cell cycle arrest (P P In vivo experiments revealed that A549 tumor-bearing mice treated with lapatinib had significantly less active tumors (as assessed by PET analysis (P P Conclusion Overall, these data suggest that lapatinib may be a clinically useful agent for the treatment of lung cancer.

  1. Inhibitory Effects of Ethyl Acetate Extract of Andrographis paniculata on NF-κB Trans-Activation Activity and LPS-Induced Acute Inflammation in Mice

    Directory of Open Access Journals (Sweden)

    Wen-Wan Chao

    2011-01-01

    Full Text Available This study was to investigate anti-inflammatory effect of Andrographis paniculata (Burm. f. Nees (Acanthaceae (AP. The effects of ethyl acetate (EtOAc extract from AP on the level of inflammatory mediators were examined first using nuclear factor kappa B (NF-κB driven luciferase assay. The results showed that AP significantly inhibited NF-κB luciferase activity and tumor necrosis factor α (TNF-α, interleukin 6 (IL-6, macrophage inflammatory protein-2 (MIP-2 and nitric oxide (NO secretions from lipopolysaccharide (LPS/interferon-γ stimulated Raw264.7 cells. To further evaluate the anti-inflammatory effects of AP in vivo, BALB/c mice were tube-fed with 0.78 (AP1, 1.56 (AP2, 3.12 (AP3 and 6.25 (AP4 mg kg−1 body weight (BW/day in soybean oil, while the control and PDTC (pyrrolidine dithiocarbamate, an anti-inflammatory agent groups were tube-fed with soybean oil only. After 1 week of tube-feeding, the PDTC group was injected with 50 mg kg−1 BW PDTC and 1 h later, all of the mice were injected with 15 mg kg−1 BW LPS. The results showed that the AP1, AP2, AP3 and PDTC groups, but not AP4, had significantly higher survival rate than the control group. Thus, the control, AP1, AP2, AP3 and PDTC groups were repeated for in vivo parameters. The results showed that the AP and PDTC groups had significantly lower TNF-α, IL-12p40, MIP-2 or NO in serum or peritoneal macrophages and infiltration of inflammatory cells into the lung of mice. The AP1 group also had significantly lower MIP-2 mRNA expression in brain. This study suggests that AP can inhibit the production of inflammatory mediators and alleviate acute hazards at its optimal dosages.

  2. Analyzing the Sensitivity of EGFR-L861Q Mutation to TKIs and A Case Report

    Directory of Open Access Journals (Sweden)

    Xingxing WANG

    2015-09-01

    Full Text Available Background and objective The significant efficacy of tyrosine kinase inhibitors (TKIs has been approved for advanced non-small cell lung cancer (NSCLC patients with activating epidermal growth factor receptor (EGFR mutations. No clear evidence exists that EGFR-L861Q is sensitive to TKIs, and the best treatment for NSCLC patients with EGFR-L861Q mutation is undetermined. This study aims to discuss the best treatment for advanced NSCLC patients with EGFR-L861Q mutation by analyzing the differences among the structures of wild-type EGFR, activating mutant EGFR-L858R, and EGFR-L861Q mutation. Method The protein structures of wild-type EGFR were reconstructed. EGFR-L858R and EGFR-L861Q mutation were activated. The differences among the three kinds of protein conformation were analyzed using homologous modeling technique. Results The structure of EGFR-L858R and wild-type EGFR exhibited notable distinctions. The structure of EGFR-L861Q mutation was different compared with wild-type EGFR and activating mutant EGFR-L858R protein conformations. NSCLC patients with EGFR-L861Q mutation were given chemotherapy as the first-line of therapy, and TKIs were applied to maintain treatment when the tumor is unchanged. Effect evaluation result was improved when the lung computed tomography lesions were reviewed. Conclusion The analysis of the protein conformation of EGFR-L861Q mutation and the curative effect of chemotherapy with TKIs could help predict the sensitivity of EGFR-L861Q to TKIs. Combining the analysis with a clinical case, maintenance treatment with TKIs may achieve satisfactory curative effect in advanced NSCLC patients who have achieved disease control after first-line chemotherapy.

  3. ACETIC ACID AND A BUFFER

    DEFF Research Database (Denmark)

    2009-01-01

    The present invention relates to a composition comprising : a) 0.01-20% wt/wt acetic acid and b) a physiologically tolerable buffer capable of maintaining acetic acid at a pH in the range of 2-7; and use of such a composition as an antimicrobial agent.......The present invention relates to a composition comprising : a) 0.01-20% wt/wt acetic acid and b) a physiologically tolerable buffer capable of maintaining acetic acid at a pH in the range of 2-7; and use of such a composition as an antimicrobial agent....

  4. Differential effects of EGFR ligands on endocytic sorting of the receptor

    DEFF Research Database (Denmark)

    Roepstorff, Kirstine; Grandal, Michael Vibo; Henriksen, Lasse;

    2009-01-01

    Endocytic downregulation is a pivotal mechanism turning off signalling from the EGF receptor (EGFR). It is well established that whereas EGF binding leads to lysosomal degradation of EGFR, transforming growth factor (TGF)-alpha causes receptor recycling. TGF-alpha therefore leads to continuous...... recycling. EGF leads to lysosomal degradation of the majority but not all EGFRs. Amphiregulin does not target EGFR for lysosomal degradation but causes fast as well as slow EGFR recycling. The Cbl ubiquitin ligases, especially c-Cbl, are responsible for EGFR ubiquitination after stimulation with all ligands...

  5. A Chimeric Cetuximab-Functionalized Corona as a Potent Delivery System for Microtubule-Destabilizing Nanocomplexes to Hepatocellular Carcinoma Cells: A Focus on EGFR and Tubulin Intracellular Dynamics.

    Science.gov (United States)

    Poojari, Radhika; Kini, Sudarshan; Srivastava, Rohit; Panda, Dulal

    2015-11-01

    In this study, we have developed microtubule destabilizing agents combretastatin A4 (CA4) or 2-methoxyestradiol (2ME) encapsulated poly(d,l-lactide-co-glycolide)-b-poly(ethylene glycol) (PLGA-b-PEG) nanocomplexes for targeted delivery to human hepatocellular carcinoma (HCC) cells. An epidermal growth factor receptor (EGFR) is known to be overexpressed in HCC cells. Therefore, the targeting moiety cetuximab (Cet), an anti-EGFR chimeric monoclonal antibody, is functionalized on the surface of these diblock copolymeric coronas. Cetuximab is associated with the extracellular domain of the EGFR; therefore, the uptake of the cetuximab conjugated nanocomplexes occurred efficiently in EGFR overexpressing HCC cells indicating potent internalization of the complex. The cetuximab targeted-PLGA-b-PEG nanocomplexes encapsulating CA4 or 2ME strongly inhibited phospho-EGFR expression, depolymerized microtubules, produced spindle abnormalities, stalled mitosis, and induced apoptosis in Huh7 cells compared to the free drugs, CA4 or 2ME. Further, the combinatorial strategy of targeted nanocomplexes, Cet-PLGA-b-PEG-CA4 NP and Cet-PLGA-b-PEG-2ME NP, significantly reduced the migration of Huh7 cells, and markedly enhanced the anticancer effects of the microtubule-targeted drugs in Huh7 cells compared to the free drugs, CA4 or 2ME. The results indicated that EGFR receptor-mediated internalization via cetuximab facilitated enhanced uptake of the nanocomplexes leading to potent anticancer efficacy in Huh7 cells. Cetuximab-functionalized PLGA-b-PEG nanocomplexes possess a strong potential for the targeted delivery of CA4 or 2ME in EGFR overexpressed HCC cells, and the strategy may be useful for selectively targeting microtubules in these cells.

  6. EGFR and KRAS quality assurance schemes in pathology: generating normative data for molecular predictive marker analysis in targeted therapy.

    NARCIS (Netherlands)

    Thunnissen, E.; Bovee, J.V.; Bruinsma, H.; Brule, A.J. van den; Dinjens, W.; Heideman, D.A.; Meulemans, E.; Nederlof, P.; Noesel, C. van; Prinsen, C.F.M.; Scheidel, K.; Ven, P.M. van de; Weger, R. de; Schuuring, E.; Ligtenberg, M.J.

    2011-01-01

    INTRODUCTION: The aim of this study was to compare the reproducibility of epidermal growth factor receptor (EGFR) immunohistochemistry (IHC), EGFR gene amplification analysis, and EGFR and KRAS mutation analysis among different laboratories performing routine diagnostic analyses in pathology in The

  7. Role of EGFR transactivation in angiotensin II signaling to extracellular regulated kinase in preglomerular smooth muscle cells.

    Science.gov (United States)

    Andresen, Bradley T; Linnoila, Jenny J; Jackson, Edwin K; Romero, Guillermo G

    2003-03-01

    Angiotensin (Ang) II promotes the phosphorylation of extracellular regulated kinase (ERK); however, the mechanisms leading to Ang II-induced ERK phosphorylation are debated. The currently accepted theory involves transactivation of epidermal growth factor receptor (EGFR). We have shown that generation of phosphatidic acid (PA) is required for the recruitment of Raf to membranes and the activation of ERK by multiple agonists, including Ang II. In the present report, we confirm that phospholipase D-dependent generation of PA is required for Ang II-mediated phosphorylation of ERK in Wistar-Kyoto and spontaneously hypertensive rat preglomerular smooth muscle cells (PGSMCs). However, EGF stimulation does not activate phospholipase D or generate PA. These observations indicate that EGF recruits Raf to membranes via a mechanism that does not involve PA, and thus, Ang II-mediated phosphorylation of ERK is partially independent of EGFR-mediated signaling cascades. We hypothesized that phosphoinositide-3-kinase (PI3K) can also act to recruit Raf to membranes; therefore, inhibition of PI3K should inhibit EGF signaling to ERK. Wortmannin, a PI3K inhibitor, inhibited EGF-mediated phosphorylation of ERK (IC50, approximately 14 nmol/L). To examine the role of the EGFR in Ang II-mediated phosphorylation of ERK we utilized 100 nmol/L wortmannin to inhibit EGFR signaling to ERK and T19N RhoA to block Ang II-mediated ERK phosphorylation. Wortmannin treatment inhibited EGF-mediated but not Ang II-mediated phosphorylation of ERK. Furthermore, T19N RhoA inhibited Ang II-mediated ERK phosphorylation, whereas T19N RhoA had significantly less effect on EGF-mediated ERK phosphorylation. We conclude that transactivation of the EGFR is not primarily responsible for Ang II-mediated activation of ERK in PGSMCs.

  8. Role of EGFR transactivation in angiotensin II signaling to extracellular regulated kinase in preglomerular smooth muscle cells.

    Science.gov (United States)

    Andresen, Bradley T; Linnoila, Jenny J; Jackson, Edwin K; Romero, Guillermo G

    2003-03-01

    Angiotensin (Ang) II promotes the phosphorylation of extracellular regulated kinase (ERK); however, the mechanisms leading to Ang II-induced ERK phosphorylation are debated. The currently accepted theory involves transactivation of epidermal growth factor receptor (EGFR). We have shown that generation of phosphatidic acid (PA) is required for the recruitment of Raf to membranes and the activation of ERK by multiple agonists, including Ang II. In the present report, we confirm that phospholipase D-dependent generation of PA is required for Ang II-mediated phosphorylation of ERK in Wistar-Kyoto and spontaneously hypertensive rat preglomerular smooth muscle cells (PGSMCs). However, EGF stimulation does not activate phospholipase D or generate PA. These observations indicate that EGF recruits Raf to membranes via a mechanism that does not involve PA, and thus, Ang II-mediated phosphorylation of ERK is partially independent of EGFR-mediated signaling cascades. We hypothesized that phosphoinositide-3-kinase (PI3K) can also act to recruit Raf to membranes; therefore, inhibition of PI3K should inhibit EGF signaling to ERK. Wortmannin, a PI3K inhibitor, inhibited EGF-mediated phosphorylation of ERK (IC50, approximately 14 nmol/L). To examine the role of the EGFR in Ang II-mediated phosphorylation of ERK we utilized 100 nmol/L wortmannin to inhibit EGFR signaling to ERK and T19N RhoA to block Ang II-mediated ERK phosphorylation. Wortmannin treatment inhibited EGF-mediated but not Ang II-mediated phosphorylation of ERK. Furthermore, T19N RhoA inhibited Ang II-mediated ERK phosphorylation, whereas T19N RhoA had significantly less effect on EGF-mediated ERK phosphorylation. We conclude that transactivation of the EGFR is not primarily responsible for Ang II-mediated activation of ERK in PGSMCs. PMID:12623996

  9. Fruit load induces changes in global gene expression and in abscisic acid (ABA) and indole acetic acid (IAA) homeostasis in citrus buds.

    Science.gov (United States)

    Shalom, Liron; Samuels, Sivan; Zur, Naftali; Shlizerman, Lyudmila; Doron-Faigenboim, Adi; Blumwald, Eduardo; Sadka, Avi

    2014-07-01

    Many fruit trees undergo cycles of heavy fruit load (ON-Crop) in one year, followed by low fruit load (OFF-Crop) the following year, a phenomenon known as alternate bearing (AB). The mechanism by which fruit load affects flowering induction during the following year (return bloom) is still unclear. Although not proven, it is commonly accepted that the fruit or an organ which senses fruit presence generates an inhibitory signal that moves into the bud and inhibits apical meristem transition. Indeed, fruit removal from ON-Crop trees (de-fruiting) induces return bloom. Identification of regulatory or metabolic processes modified in the bud in association with altered fruit load might shed light on the nature of the AB signalling process. The bud transcriptome of de-fruited citrus trees was compared with those of ON- and OFF-Crop trees. Fruit removal resulted in relatively rapid changes in global gene expression, including induction of photosynthetic genes and proteins. Altered regulatory mechanisms included abscisic acid (ABA) metabolism and auxin polar transport. Genes of ABA biosynthesis were induced; however, hormone analyses showed that the ABA level was reduced in OFF-Crop buds and in buds shortly following fruit removal. Additionally, genes associated with Ca(2+)-dependent auxin polar transport were remarkably induced in buds of OFF-Crop and de-fruited trees. Hormone analyses showed that auxin levels were reduced in these buds as compared with ON-Crop buds. In view of the auxin transport autoinhibition theory, the possibility that auxin distribution plays a role in determining bud fate is discussed.

  10. Placebo controlled, crossover validation study of oral ibuprofen and topical hydrocortisone-21-acetate for a model of ultraviolet B radiation (UVR)-induced pain and inflammation

    OpenAIRE

    Rother M; Rother I

    2011-01-01

    Matthias Rother, Ilka RotherDepartment of Clinical Operations, X-pert Med GmbH, Graefelfing, GermanyBackground: Pain related to ultraviolet B radiation (UVR) induced sunburn is an established, simple, acute pain model. One of the major criticisms is related to the potential dermal adverse events caused by the UVR exposure. This study tried to validate the model for oral and topical drugs and to define the minimum required UVR exposure.Methods: This subject- and observer-blinded, placebo-contr...

  11. Endophilin-1 regulates blood-brain barrier permeability by controlling ZO-1 and occludin expression via the EGFR-ERK1/2 pathway.

    Science.gov (United States)

    Liu, Wenjing; Wang, Ping; Shang, Chao; Chen, Lin; Cai, Heng; Ma, Jun; Yao, Yilong; Shang, Xiuli; Xue, Yixue

    2014-07-21

    The blood-brain barrier (BBB) plays a pivotal role in maintenance and regulation of the neural microenvironment. Brain endothelial cells (BECs), held together by tight junctions (TJs), have a primary role in restricting the permeability of the BBB. Endophilin-1 is a multifunctional protein that influences epithelial growth factor receptor (EGFR) endocytosis and degradation and plays an important role in regulating the glomerular filtration barrier in the kidney. Endophilin-1 likely plays a similar role in controlling BBB permeability. In this study, we therefore analyzed the expression and function of endophilin-1 in the human BEC line hCMEC/D3. Our results show that endophilin-1 over-expression reduced the expression of the TJ-associated proteins ZO-1 and occludin and increased the paracellular permeability of hCMEC/D3 cells, whereas silencing of endogenous endophilin-1 yielded the opposite results. Over-expression of ZO-1 and occludin prevented the increase in permeability induced by endophilin-1 over-expression, whereas down-regulation of ZO-1 and occludin prevented the reduction in permeability induced by endophilin-1 silencing. Co-localization and co-immunoprecipitation experiments suggested that endophilin-1 interacts with the EGFR. The levels of EGFR and its downstream effector phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) are significantly decreased when endophilin-1 is over-expressed. Conversely, endophilin-1 down-regulation led to markedly increased levels of these proteins. In addition, the reduced permeability induced by endophilin-1 down-regulation was blocked by AG1478 and PD98059, inhibitors of EGFR and ERK1/2, respectively. Up-regulation of ZO-1 and occludin was blocked by the EGFR and ERK1/2 inhibitors. These results suggest that endophilin-1 regulates BBB permeability by controlling ZO-1 and occludin expression via the EGFR-ERK1/2 pathway in BECs.

  12. Over-expression of EGFR in Breast Cancer

    Institute of Scientific and Technical Information of China (English)

    BO Ai-hua; HOU Jin-chao; LAN Yong-hao; TIAN Ya-ting; ZHANG Jun-yan

    2008-01-01

    Objective:To explore the relationship of overexpression of epidermal growth factor receptor(EGFR)in occurrence,development and treatment of breast cancer. Methods:Samples of 46 breast adenoma tissues and 86 breast cancer tissues were regularly dehydrate-fixed,embedded in paraffin,sliced in to 5 μm thick,stained with SABC immunohistochemistry and coloured with DAB. Results:The positive staining of EGFR was shown as brown- yellow and distributed in cytoplasm.The positive rates in the tissues of breast adenosis and breast cancer were 17.04%(6/46)and 56.98%(49/86)respectively.The positive rates of EGFR in the tissue of invasive ductal carcinoma was 64.49%(41/59),which was significantly higher than that in in situ carcinoma(P<0.05).The positive rate of lymph metastasis group was higher than that in non-lymph metastasis group (P<0.05). Conclusion:The overexpression of EGFR was related with occurrence,lymph metastasis and pathologic types of breast cancer.The examination of EGFR in the breast cancer can serve as a guidance for target chemotherapy.

  13. Development of personalized treatments in lung cancer: focusing on the EGFR mutations and beyond

    Directory of Open Access Journals (Sweden)

    Suda K

    2013-08-01

    Full Text Available Kenichi Suda,1,2 Tetsuya Mitsudomi1 1Division of Thoracic Surgery, Department of Surgery, Kinki University Faculty of Medicine, Osaka-Sayama, Japan; 2Department of Surgery and Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan Abstract: Lung cancers with epidermal growth factor receptor (EGFR gene mutation account for ~40% of adenocarcinoma in East Asians and ~15% of that in Caucasians, which makes them one of the most common molecularly defined lung cancer subsets. The role of EGFR mutation as a strong predictive biomarker of response to EGFR-tyrosine kinase inhibitors (TKIs was finally confirmed by the biomarker analysis of Iressa Pan-Asian Study (IPASS. Since the 2004 discovery of EGFR mutation in lung cancer, the EGFR mutation and EGFR-TKI treatment have been widely studied. These include characteristics of lung cancers with EGFR mutations; clinical efficacies and adverse effects of EGFR-TKIs in patients with EGFR-mutated lung cancers; development of novel EGFR-TKIs that may prolong progression-free survival of these patients or overcome resistance to first-generation EGFR-TKIs (gefitinib and erlotinib; optimal treatment schedules for EGFR-TKIs to delay emergence of resistance; molecular mechanisms of acquired resistance to EGFR-TKIs; treatment strategies after patients acquire resistance to EGFR-TKIs; and predictive biomarkers for EGFR-TKIs among patients with EGFR-mutated lung cancers. Some of these results are widely accepted, while others are apparent only in cell line models, preclinical animal models, or retrospective analyses (and sometimes conflict with each other. In this review, we summarize accumulated reports from the past decade, especially focusing on unanswered but important clinical questions in treating patients with EGFR-mutated lung cancers. Keywords: epidermal growth factor receptor mutation, predictive biomarkers, personalized therapy, molecular target, adjuvant therapy, acquired resistance

  14. Nuclear trafficking of EGFR by Vps34 represses Arf expression to promote lung tumor cell survival.

    Science.gov (United States)

    Dayde, D; Guerard, M; Perron, P; Hatat, A-S; Barrial, C; Eymin, B; Gazzeri, S

    2016-07-28

    Epidermal growth factor receptor (EGFR) is a cell surface receptor that has an essential role in cell proliferation and survival, and overexpression of EGFR is a common feature of human cancers. In Non-small-cell lung cancer (NSCLC), activating mutations of EGFR have also been described. We recently showed that mutant EGFR-L858R inhibits the expression of the p14ARF tumor-suppressor protein to promote cell survival. In this study, we defined the molecular bases by which EGFR controls Arf expression. Using various lung tumor models, we showed that EGF stimulation inhibits Arf transcription by a mechanism involving the nuclear transport and recruitment of EGFR to the Arf promoter. We unraveled the vesicular trafficking protein Vps34 as a mediator of EGFR nuclear trafficking and showed that its neutralization prevents the accumulation of EGFR to the Arf promoter in response to ligand activation. Finally, in lung tumor cells that carry mutant EGFR-L858R, we demonstrated that inhibition of Vps34 using small interfering RNA restrains nuclear EGFR location and restores Arf expression leading to apoptosis. These findings identify the Arf tumor suppressor as a new transcriptional target of nuclear EGFR and highlight Vps34 as an important regulator of the nuclear EGFR/Arf survival pathway. As a whole, they provide a mechanistic explanation to the inverse correlation between nuclear expression of EGFR and overall survival in NSCLC patients. PMID:26686095

  15. Acetate metabolism in Methanothrix soehngenii.

    NARCIS (Netherlands)

    Jetten, M.S.M.

    1991-01-01

    Acetate is quantitatively the most important intermediate in the anaerobic degradation of soluble organic matter. The conversion rate of acetate by methanogenic bacteria is proposed to be the rate limiting step in this degradation The study of acetoclastic methanogens, therefore is of relevance to o

  16. Andrographolide suppresses thymic stromal lymphopoietin in phorbol myristate acetate/calcium ionophore A23187-activated mast cells and 2,4-dinitrofluorobenzene-induced atopic dermatitis-like mice model

    Directory of Open Access Journals (Sweden)

    Li CX

    2016-02-01

    Full Text Available Chun-xiao Li,* Hua-guo Li,* Hui Zhang,* Ru-hong Cheng, Ming Li, Jian-ying Liang, Yan Gu, Bo Ling, Zhi-rong Yao, Hong Yu Department of Dermatology, Xinhua Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China *These authors contributed equally to this work Background: Atopic dermatitis (AD is one of the most common inflammatory cutaneous diseases. Thymic stromal lymphopoietin (TSLP has been demonstrated to be an important immunologic factor in the pathogenesis of AD. The production of TSLP can be induced by a high level of intracellular calcium concentration and activation of the receptor-interacting protein 2/caspase-1/NF-κB pathway. Andrographolide (ANDRO, a natural bicyclic diterpenoid lactone, has been found to exert anti-inflammatory effects in gastrointestinal inflammatory disorders through suppressing the NF-κB pathway. Objective: To explore the effect of ANDRO on the production of TSLP in human mast cells and AD mice model. Methods: We utilized enzyme-linked immunosorbent assay, real-time reverse transcription polymerase chain reaction analysis, Western blot analysis, and immunofluorescence staining assay to investigate the effects of ANDRO on AD. Results: ANDRO ameliorated the increase in the intracellular calcium, protein, and messenger RNA levels of TSLP induced by phorbol myristate acetate/calcium ionophore A23187, through the blocking of the receptor-interacting protein 2/caspase-1/NF-κB pathway in human mast cell line 1 cells. ANDRO, via oral or local administration, also attenuated clinical symptoms in 2,4-dinitrofluorobenzene-induced AD mice model and suppressed the levels of TSLP in lesional skin. Conclusion: Taken together, ANDRO may be a potential therapeutic agent for AD through suppressing the expression of TSLP. Keywords: atopic dermatitis, thymic stromal lymphopoietin, andrographolide, human mast cell

  17. The efficacy of lapatinib in metastatic breast cancer with HER2 non-amplified primary tumors and EGFR positive circulating tumor cells: a proof-of-concept study.

    Directory of Open Access Journals (Sweden)

    Justin Stebbing

    Full Text Available BACKGROUND: Analysis of circulating tumor cells (CTCs provides real-time measures of cancer sub-populations with potential for CTC-directed therapeutics. We examined whether lapatinib which binds both HER2 and EGFR could induce depletion of the EGFR-positive pool of CTCs, which may in turn lead to clinical benefits. PATIENTS AND METHODS: Patients with metastatic breast cancer and HER2 non-amplified primary tumors with EGFR-positive CTCs were recruited and lapatinib 1500 mg daily was administered, in a standard two step phase 2 trial. RESULTS: There were no responses leading to termination at the first analysis with 16 patients recruited out of 43 screened. In 6 out of 14 (43% individuals eligible for the efficacy analysis, a decrease in CTCs was observed with most of these having a greater decrease in their EGFR-positive CTC pool. CONCLUSIONS: This is one of the first studies of CTC-directed therapeutics and suggests that lapatinib monotherapy is not having any demonstrable clinical effects by reducing the EGFR-positive pool of CTCs in HER2 non-amplified primary tumors. Our attempt to expand the pool of patients eligible for a targeted therapy was unsuccessful; the role of clonal populations in cancer biology and therapeutic strategies to control them will require extensive evaluation in years to come. TRIAL REGISTRATION: Clinical trials.gov NCT00820924.

  18. EGFR-Targeted Therapeutics: Focus on SCCHN and NSCLC

    Directory of Open Access Journals (Sweden)

    Martin Sattler

    2008-01-01

    Full Text Available Cancers of the head and neck and of the lung are associated with high morbidity and mortality rates that have remained relatively unchanged for more than 3 decades, despite advances in radiation therapies and chemotherapies over the same time. It is generally believed that the efficacy of standard therapy regimens has reached a plateau for these cancers. The discovery of specific aberrant molecular signaling pathways in solid tumors has afforded promising new directions for newer “targeted” cancer therapeutics. Among these, the epidermal growth factor receptor (EGFR shows promise as a therapeutic target. Clinical studies have demonstrated that this targeted approach provides clinically meaningful benefit. This article reviews EGFR-targeted therapies in use and in development, with a focus on the role of EGFR in the pathophysiology of head and neck and lung cancer, and new concepts being investigated to improve outcomes with these agents.

  19. No Incidence of BRAF Mutations in Salivary Gland Carcinomas—Implications for Anti-EGFR Therapies

    Directory of Open Access Journals (Sweden)

    Regine Dahse

    2009-01-01

    These findings imply that SGC rarely acquires mutations that result in a constitutive activation of the signaling cascade downstream of EGFR and this pleads in favor of further therapeutic trials with EGFR-targeting monoclonal antibodies.

  20. ZD6474, an inhibitor of VEGFR and EGFR tyrosine kinase activity in combination with radiotherapy

    International Nuclear Information System (INIS)

    Radiation enhances both epithelial growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) expression, which are a part of key pathways for tumor progression. Some tumors may not respond well to EGFR inhibitors alone or may develop resistance to EGFR inhibitors. Therefore, drug therapy targeted to VEGF receptors and EGFRs, when combined with radiotherapy (RT), may improve tumor control and provide wider applicability. This article focuses on ZD6474, an inhibitor of EGFR and VEGF receptor signaling in combination with RT. We discuss preclinical and clinical studies with RT and inhibitors of VEGF or EGFR signaling first. We then address issues associated with ZD6474 pharmacokinetic dosing, and scheduling when combined with RT. We also discuss ZD6474 in the context of anti-EGFR therapy resistance. Dual inhibition of EGFR and VEGF receptor signaling pathways shows promise in enhancing RT efficacy

  1. Acetate/acetyl-CoA metabolism associated with cancer fatty acid synthesis: overview and application.

    Science.gov (United States)

    Yoshii, Yukie; Furukawa, Takako; Saga, Tsuneo; Fujibayashi, Yasuhisa

    2015-01-28

    Understanding cancer-specific metabolism is important for identifying novel targets for cancer diagnosis and therapy. Induced acetate/acetyl CoA metabolism is a notable feature that is related to fatty acid synthesis supporting tumor growth. In this review, we focused on the recent findings related to cancer acetate/acetyl CoA metabolism. We also introduce [1-¹¹C]acetate positron emission tomography (PET), which is a useful tool to visualize up-regulation of acetate/acetyl CoA metabolism in cancer, and discuss the utility of [1-¹¹C]acetate PET in cancer diagnosis and its application to personalized medicine.

  2. Biogas Production through the Syntrophic Acetate-Oxidising Pathway. Characterisation and Detection of Syntrophic Acetate- Oxidising Bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Westerholm, Maria [Faculty of Natural Resources and Agricultural Sciences, Dept. of Microbiology, Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)

    2012-11-01

    Biogas produced from wastes, residues and energy crops has promising potential to reduce greenhouse gas emissions and to secure future energy supply. Methane is the energy-rich component of biogas, and is formed as the end product during degradation of organic material without oxygen (anaerobic). Acetate is an important intermediate in anaerobic degradation and can be converted to methane through two pathways: aceticlastic methanogenesis and syntrophic acetate oxidation (SAO). SAO is a two-step reaction, consisting of acetate oxidation to hydrogen and carbon dioxide by syntrophic acetate-oxidising bacteria (SAOB), followed by conversion of these products to methane by hydrogenotrophic methanogens. Ammonia and acetate concentration, hydraulic retention time, temperature and methanogenic population structure are operational parameters considered to influence the acetate conversion pathway. This thesis sought to increase understanding of SAO by examining syntrophic acetate oxidisers in pure culture, co-culture and methanogenic reactors. Two novel species of SAOB, Syntrophaceticus schinkii and Tepidanaerobacter acetatoxydans, were isolated and their phenotypic and phylogenetic traits were characterised. Quantitative molecular approaches were developed and applied to determine structural dynamics in the methane-producing population in a mesophilic biogas reactor during an ammonia-induced shift from aceticlastic to syntrophic acetate degradation. The abundance of SAOB increased, with a simultaneous decrease in aceticlastic methanogens. The majority of known SAOB are considered acetogens, and gradually increased ammonia concentration was shown to cause distinct shifts in the putative acetogenic population structure in mesophilic biogas reactors. However, the acetogenic bacterial abundance remained relatively stable. Bioaugmentation of syntrophic acetate-oxidising cultures did not improve process performance or support establishment of SAO as the dominant acetate

  3. Dermatologic Toxicities from Monoclonal Antibodies and Tyrosine Kinase Inhibitors against EGFR: Pathophysiology and Management

    OpenAIRE

    Shaad E. Abdullah; Missak Haigentz; Bilal Piperdi

    2012-01-01

    Epidermal growth factor receptor (EGFR) inhibition has now been well established as an effective treatment for various cancers. The EGFR belongs to the ErbB family of tyrosine kinase receptors which regulate tumor cell differentiation, survival and proliferation. Activation of EGFR drives tumorigenesis in lung, head and neck, colorectal and pancreatic cancers. Irrespective of the type of cancer being treated and the mechanism by which tumor EGFR drives tumorigenesis, the major side effect of ...

  4. Increased concentrations of growth factors and activation of the EGFR system in breast cancer

    DEFF Research Database (Denmark)

    Aalund Olsen, Dorte; Bechmann, Troels; Østergaard, Birthe;

    2012-01-01

    In this study the total and phosphorylated amount of epidermal growth factor receptor 1 (EGFR) and 2 (HER2) were measured together with EGFR ligands in tissue samples of breast cancer patients in order to investigate interrelations and possible prognostic values.......In this study the total and phosphorylated amount of epidermal growth factor receptor 1 (EGFR) and 2 (HER2) were measured together with EGFR ligands in tissue samples of breast cancer patients in order to investigate interrelations and possible prognostic values....

  5. Which biomarker predicts benefit from EGFR-TKI treatment for patients with lung cancer?

    OpenAIRE

    Uramoto, H; Mitsudomi, T.

    2007-01-01

    Subsets of patients with non-small cell lung cancer respond remarkably well to small molecule tyrosine kinase inhibitors (TKI) specific for epidermal growth factor receptor (EGFR) such as gefitinib or erlotinib. In 2004, it was found that EGFR mutations occurring in the kinase domain are strongly associated with EGFR-TKI sensitivity. However, subsequent studies revealed that this relationship was not perfect and various predictive markers have been reported. These include EGFR gene copy numbe...

  6. Oligo-Carrageenan Kappa-Induced Reducing Redox Status and Activation of TRR/TRX System Increase the Level of Indole-3-acetic Acid, Gibberellin A3 and trans-Zeatin in Eucalyptus globulus Trees

    Directory of Open Access Journals (Sweden)

    Alberto González

    2014-08-01

    Full Text Available Eucalyptus globulus trees treated with oligo-carrageenan (OC kappa showed an increase in NADPH, ascorbate and glutathione levels and activation of the thioredoxin reductase (TRR/thioredoxin (TRX system which enhance photosynthesis, basal metabolism and growth. In order to analyze whether the reducing redox status and the activation of thioredoxin reductase (TRR/thioredoxin (TRX increased the level of growth-promoting hormones, trees were treated with water (control, with OC kappa, or with inhibitors of ascorbate synthesis, lycorine, glutathione synthesis, buthionine sulfoximine (BSO, NADPH synthesis, CHS-828, and thioredoxin reductase activity, auranofine, and with OC kappa, and cultivated for four additional months. Eucalyptus trees treated with OC kappa showed an increase in the levels of the auxin indole 3-acetic acid (IAA, gibberellin A3 (GA3 and the cytokinin trans-zeatin (t-Z as well as a decrease in the level of the brassinosteroid epi-brassinolide (EB. In addition, treatment with lycorine, BSO, CHS-828 and auranofine inhibited the increase in IAA, GA3 and t-Z as well as the decrease in EB levels. Thus, the reducing redox status and the activation of TRR/TRX system induced by OC kappa increased the levels of IAA, GA3 and t-Z levels determining, at least in part, the stimulation of growth in Eucalyptus trees.

  7. EGFR-inhibitors, radiotherapy and normal tissue toxicity

    DEFF Research Database (Denmark)

    Eriksen, J. G.

    2015-01-01

    EGFR-inhibitors have been used in several clinical settings during the last decade and side-effects related to normal tissues like the skin, mucosa and kidney has been well described. However, when EGFR-inhibitors are combined with radiotherapy, then different skin and mucosa toxicity profiles can...... variations that are shared between tumour and normal tissue like skin and mucosa. At present, it is not possible to predict which patients that will develop severe skin toxicity and thereby potentially benefit from EGFRinhibition in terms of tumour response. However, emerging data suggests that certain...

  8. Predictive efficacy of low burden EGFR mutation detected by next-generation sequencing on response to EGFR tyrosine kinase inhibitors in non-small-cell lung carcinoma.

    Directory of Open Access Journals (Sweden)

    Hye Sook Kim

    Full Text Available Direct sequencing remains the most widely used method for the detection of epidermal growth factor receptor (EGFR mutations in lung cancer; however, its relatively low sensitivity limits its clinical use. The objective of this study was to investigate the sensitivity of detecting an epidermal growth factor receptor (EGFR mutation from peptide nucleic acid-locked nucleic acid polymerase chain reaction (PNA-LNA PCR clamp and Ion Torrent Personal Genome Machine (PGM techniques compared to that by direct sequencing. Furthermore, the predictive efficacy of EGFR mutations detected by PNA-LNA PCR clamp was evaluated. EGFR mutational status was assessed by direct sequencing, PNA-LNA PCR clamp, and Ion Torrent PGM in 57 patients with non-small cell lung cancer (NSCLC. We evaluated the predictive efficacy of PNA-LNA PCR clamp on the EGFR-TKI treatment in 36 patients with advanced NSCLC retrospectively. Compared to direct sequencing (16/57, 28.1%, PNA-LNA PCR clamp (27/57, 47.4% and Ion Torrent PGM (26/57, 45.6% detected more EGFR mutations. EGFR mutant patients had significantly longer progressive free survival (14.31 vs. 21.61 months, P = 0.003 than that of EGFR wild patients when tested with PNA-LNA PCR clamp. However, no difference in response rate to EGFR TKIs (75.0% vs. 82.4%, P = 0.195 or overall survival (34.39 vs. 44.10 months, P = 0.422 was observed between the EGFR mutations by direct sequencing or PNA-LNA PCR clamp. Our results demonstrate firstly that patients with EGFR mutations were detected more frequently by PNA-LNA PCR clamp and Ion Torrent PGM than those by direct sequencing. EGFR mutations detected by PNA-LNA PCR clamp may be as a predicative factor for EGFR TKI response in patients with NSCLC.

  9. TGF-β and Hypoxia/Reoxygenation Promote Radioresistance of A549 Lung Cancer Cells through Activation of Nrf2 and EGFR

    Directory of Open Access Journals (Sweden)

    Sae-lo-oom Lee

    2016-01-01

    Full Text Available Although many studies have examined the roles of hypoxia and transforming growth factor- (TGF- β separately in the tumor microenvironment, the effects of simultaneous treatment with hypoxia/reoxygenation and TGF-β on tumor malignancy are unclear. Here, we investigated the effects of redox signaling and oncogenes on cell proliferation and radioresistance in A549 human lung cancer cells in the presence of TGF-β under hypoxia/reoxygenation conditions. Combined treatment with TGF-β and hypoxia activated epidermal growth factor receptor (EGFR and nuclear factor (erythroid-derived 2-like 2 (Nrf2, a redox-sensitive transcription factor. Interestingly, Nrf2 knockdown suppressed the effects of combined treatment on EGFR phosphorylation. In addition, blockade of EGFR signaling also suppressed induction of Nrf2 following combined treatment with hypoxia and TGF-β, indicating that the combined treatment induced positive crosstalk between Nrf2 and EGFR. TGF-β and hypoxia/reoxygenation increased the accumulation of reactive oxygen species (ROS, while treatment with N-acetyl-L-cysteine abolished the activation of Nrf2 and EGFR. Treatment with TGF-β under hypoxic conditions increased the proliferation of A549 cells compared with that after vehicle treatment. Moreover, cells treated with the combined treatment exhibited resistance to ionizing radiation (IR, and knockdown of Nrf2 increased IR-induced cell death under these conditions. Thus, taken together, our findings suggested that TGF-β and hypoxia/reoxygenation promoted tumor progression and radioresistance of A549 cells through ROS-mediated activation of Nrf2 and EGFR.

  10. JAK2 inhibition sensitizes resistant EGFR-mutant lung adenocarcinoma to tyrosine kinase inhibitors.

    Science.gov (United States)

    Gao, Sizhi P; Chang, Qing; Mao, Ninghui; Daly, Laura A; Vogel, Robert; Chan, Tyler; Liu, Shu Hui; Bournazou, Eirini; Schori, Erez; Zhang, Haiying; Red Brewer, Monica; Pao, William; Morris, Luc; Ladanyi, Marc; Arcila, Maria; Manova-Todorova, Katia; de Stanchina, Elisa; Norton, Larry; Levine, Ross L; Altan-Bonnet, Gregoire; Solit, David; Zinda, Michael; Huszar, Dennis; Lyden, David; Bromberg, Jacqueline F

    2016-01-01

    Lung adenocarcinomas with mutant epidermal growth factor receptor (EGFR) respond to EGFR-targeted tyrosine kinase inhibitors (TKIs), but resistance invariably occurs. We found that the Janus kinase (JAK)/signal transduction and activator of transcription 3 (STAT3) signaling pathway was aberrantly increased in TKI-resistant EGFR-mutant non-small cell lung cancer (NSCLC) cells. JAK2 inhibition restored sensitivity to the EGFR inhibitor erlotinib in TKI-resistant cell lines and xenograft models of EGFR-mutant TKI-resistant lung cancer. JAK2 inhibition uncoupled EGFR from its negative regulator, suppressor of cytokine signaling 5 (SOCS5), consequently increasing EGFR abundance and restoring the tumor cells' dependence on EGFR signaling. Furthermore, JAK2 inhibition led to heterodimerization of mutant and wild-type EGFR subunits, the activity of which was then blocked by TKIs. Our results reveal a mechanism whereby JAK2 inhibition overcomes acquired resistance to EGFR inhibitors and support the use of combination therapy with JAK and EGFR inhibitors for the treatment of EGFR-dependent NSCLC. PMID:27025877

  11. Emerging Roles of MicroRNAs in EGFR-Targeted Therapies for Lung Cancer

    Directory of Open Access Journals (Sweden)

    Fei Han

    2015-01-01

    Full Text Available Lung cancer is a leading cause of cancer mortality worldwide. Several molecular pathways underlying mechanisms of this disease have been partly elucidated, among which the epidermal growth factor receptor (EGFR pathway is one of the well-known signaling cascades that plays a critical role in tumorigenesis. Dysregulation of the EGFR signaling is frequently found in lung cancer. The strategies to effectively inhibit EGFR signaling pathway have been mounted for developing anticancer therapeutic agents. However, most anti-EGFR-targeted agents fail to repress cancer progression because of developing drug-resistance. Therefore, studies of the mechanisms underpinning the resistance toward anti-EGFR agents may provide important findings for lung cancer treatment using anti-EGFR therapies. Recently, increasing numbers of miRNAs are correlated with the drug resistance of lung cancer cells to anti-EGFR agents, indicating that miRNAs may serve as novel targets and/or promising predictive biomarkers for anti-EGFR therapy. In this paper, we summarize the emerging role of miRNAs as regulators to modulate the EGFR signaling and the resistance of lung cancer cells to anti-EGFR therapy. We also highlight the evidence supporting the use of miRNAs as biomarkers for response to anti-EGFR agents and as novel therapeutic targets to circumvent the resistance of lung cancer cells to EGFR inhibitors.

  12. File list: Oth.ALL.20.EGFR.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.ALL.20.EGFR.AllCell hg19 TFs and others EGFR All cell types SRX853217,SRX853214...,SRX853216,SRX853215 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.ALL.20.EGFR.AllCell.bed ...

  13. File list: Oth.ALL.10.EGFR.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  14. File list: Oth.Utr.10.EGFR.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  15. File list: Oth.ALL.50.EGFR.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  16. File list: Oth.Utr.20.EGFR.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  17. File list: Oth.Utr.05.EGFR.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  18. File list: Oth.Utr.50.EGFR.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  19. File list: Oth.ALL.05.EGFR.AllCell [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.ALL.05.EGFR.AllCell hg19 TFs and others EGFR All cell types SRX853214,SRX853217...,SRX853215,SRX853216 http://dbarchive.biosciencedbc.jp/kyushu-u/hg19/assembled/Oth.ALL.05.EGFR.AllCell.bed ...

  20. Therapeutic resistance in cancer:microRNA regulation of EGFR signaling networks

    Institute of Scientific and Technical Information of China (English)

    German G. Gomez; Jill Wykosky; Ciro Zanca; Frank B. Furnari; Webster K. Cavenee

    2013-01-01

    Receptor tyrosine kinases (RTKs) such as the epidermal growth factor receptor (EGFR) regulate cellular homeostatic processes. EGFR activates downstream signaling cascades that promote tumor cell survival, proliferation and migration. Dysregulation of EGFR signaling as a consequence of overexpression, amplification and mutation of the EGFR gene occurs frequently in several types of cancers and many become dependent on EGFR signaling to maintain their malignant phenotypes. Consequently, concerted efforts have been mounted to develop therapeutic agents and strategies to effectively inhibit EGFR. However, limited therapeutic beneifts to cancer patients have been derived from EGFR-targeted therapies. A well-documented obstacle to improved patient survival is the presence of EGFR-inhibitor resistant tumor cell variants within heterogeneous tumor cell masses. Here, we summarize the mechanisms by which tumors resist EGFR-targeted therapies and highlight the emerging role of microRNAs (miRs) as downstream effector molecules utilized by EGFR to promote tumor initiation, progression and that play a role in resistance to EGFR inhibitors. We also examine evidence supporting the utility of miRs as predictors of response to targeted therapies and novel therapeutic agents to circumvent EGFR-inhibitor resistance mechanisms.

  1. EGFR Signaling in the Brain Is Necessary for Olfactory Learning in "Drosophila" Larvae

    Science.gov (United States)

    Rahn, Tasja; Leippe, Matthias; Roeder, Thomas; Fedders, Henning

    2013-01-01

    Signaling via the epidermal growth factor receptor (EGFR) pathway has emerged as one of the key mechanisms in the development of the central nervous system in "Drosophila melanogaster." By contrast, little is known about the functions of EGFR signaling in the differentiated larval brain. Here, promoter-reporter lines of EGFR and its most prominent…

  2. Activation of EGFR/ERBB2 via Pathways Involving ERK1/2, P38 MAPK, AKT and FOXO Enhances Recovery of Diabetic Hearts from Ischemia-Reperfusion Injury

    Science.gov (United States)

    Akhtar, Saghir; Yousif, Mariam H. M.; Chandrasekhar, Bindu; Benter, Ibrahim F.

    2012-01-01

    This study characterized the effects of diabetes and/or ischemia on epidermal growth factor receptor, EGFR, and/or erbB2 signaling pathways on cardiac function. Isolated heart perfusion model of global ischemia was used to study the effect of chronic inhibition or acute activation of EGFR/erbB2 signaling on cardiac function in a rat model of type-1 diabetes. Induction of diabetes with streptozotocin impaired recovery of cardiac function (cardiac contractility and hemodynamics) following 40 minutes of global ischemia in isolated hearts. Chronic treatment with AG825 or AG1478, selective inhibitors of erbB2 and EGFR respectively, did not affect hyperglycemia but led to an exacerbation whereas acute administration of the EGFR ligand, epidermal growth factor (EGF), led to an improvement in cardiac recovery in diabetic hearts. Diabetes led to attenuated dimerization and phosphorylation of cardiac erbB2 and EGFR receptors that was associated with reduced signaling via extracellular-signal-regulated kinase 1/2 (ERK1/2), p38 mitogen activated protein (MAP) kinase and AKT (protein kinase B). Ischemia was also associated with reduced cardiac signaling via these molecules whereas EGF-treatment opposed diabetes and/or ischemia induced changes in ERK1/2, p38 MAP kinase, and AKT-FOXO signaling. Losartan treatment improved cardiac function in diabetes but also impaired EGFR phosphorylation in diabetic heart. Co-administration of EGF rescued Losartan-mediated reduction in EGFR phosphorylation and significantly improved cardiac recovery more than with either agent alone. EGFR/erbB2 signaling is an important cardiac survival pathway whose activation, particularly in diabetes, ischemia or following treatment with drugs that inhibit this cascade, significantly improves cardiac function. These findings may have clinical relevance particularly in the treatment of diabetes-induced cardiac dysfunction. PMID:22720029

  3. Activation of EGFR/ERBB2 via pathways involving ERK1/2, P38 MAPK, AKT and FOXO enhances recovery of diabetic hearts from ischemia-reperfusion injury.

    Directory of Open Access Journals (Sweden)

    Saghir Akhtar

    Full Text Available This study characterized the effects of diabetes and/or ischemia on epidermal growth factor receptor, EGFR, and/or erbB2 signaling pathways on cardiac function. Isolated heart perfusion model of global ischemia was used to study the effect of chronic inhibition or acute activation of EGFR/erbB2 signaling on cardiac function in a rat model of type-1 diabetes. Induction of diabetes with streptozotocin impaired recovery of cardiac function (cardiac contractility and hemodynamics following 40 minutes of global ischemia in isolated hearts. Chronic treatment with AG825 or AG1478, selective inhibitors of erbB2 and EGFR respectively, did not affect hyperglycemia but led to an exacerbation whereas acute administration of the EGFR ligand, epidermal growth factor (EGF, led to an improvement in cardiac recovery in diabetic hearts. Diabetes led to attenuated dimerization and phosphorylation of cardiac erbB2 and EGFR receptors that was associated with reduced signaling via extracellular-signal-regulated kinase 1/2 (ERK1/2, p38 mitogen activated protein (MAP kinase and AKT (protein kinase B. Ischemia was also associated with reduced cardiac signaling via these molecules whereas EGF-treatment opposed diabetes and/or ischemia induced changes in ERK1/2, p38 MAP kinase, and AKT-FOXO signaling. Losartan treatment improved cardiac function in diabetes but also impaired EGFR phosphorylation in diabetic heart. Co-administration of EGF rescued Losartan-mediated reduction in EGFR phosphorylation and significantly improved cardiac recovery more than with either agent alone. EGFR/erbB2 signaling is an important cardiac survival pathway whose activation, particularly in diabetes, ischemia or following treatment with drugs that inhibit this cascade, significantly improves cardiac function. These findings may have clinical relevance particularly in the treatment of diabetes-induced cardiac dysfunction.

  4. Activation of EGFR/ERBB2 via pathways involving ERK1/2, P38 MAPK, AKT and FOXO enhances recovery of diabetic hearts from ischemia-reperfusion injury.

    Science.gov (United States)

    Akhtar, Saghir; Yousif, Mariam H M; Chandrasekhar, Bindu; Benter, Ibrahim F

    2012-01-01

    This study characterized the effects of diabetes and/or ischemia on epidermal growth factor receptor, EGFR, and/or erbB2 signaling pathways on cardiac function. Isolated heart perfusion model of global ischemia was used to study the effect of chronic inhibition or acute activation of EGFR/erbB2 signaling on cardiac function in a rat model of type-1 diabetes. Induction of diabetes with streptozotocin impaired recovery of cardiac function (cardiac contractility and hemodynamics) following 40 minutes of global ischemia in isolated hearts. Chronic treatment with AG825 or AG1478, selective inhibitors of erbB2 and EGFR respectively, did not affect hyperglycemia but led to an exacerbation whereas acute administration of the EGFR ligand, epidermal growth factor (EGF), led to an improvement in cardiac recovery in diabetic hearts. Diabetes led to attenuated dimerization and phosphorylation of cardiac erbB2 and EGFR receptors that was associated with reduced signaling via extracellular-signal-regulated kinase 1/2 (ERK1/2), p38 mitogen activated protein (MAP) kinase and AKT (protein kinase B). Ischemia was also associated with reduced cardiac signaling via these molecules whereas EGF-treatment opposed diabetes and/or ischemia induced changes in ERK1/2, p38 MAP kinase, and AKT-FOXO signaling. Losartan treatment improved cardiac function in diabetes but also impaired EGFR phosphorylation in diabetic heart. Co-administration of EGF rescued Losartan-mediated reduction in EGFR phosphorylation and significantly improved cardiac recovery more than with either agent alone. EGFR/erbB2 signaling is an important cardiac survival pathway whose activation, particularly in diabetes, ischemia or following treatment with drugs that inhibit this cascade, significantly improves cardiac function. These findings may have clinical relevance particularly in the treatment of diabetes-induced cardiac dysfunction.

  5. A CLONALLY DERIVED CELL LINE,9L-EGFR IS USEFUL FOR THE STUDIES OF CANCER CELLS BEARING EGF RECEPTOR

    Institute of Scientific and Technical Information of China (English)

    Lin Qi; Rajesh Agarwal; Rana Singh; Gail S. Harrisona; L.Michael Glodea

    2003-01-01

    Since the epidermal growth factor receptor (EGFR) is a key regulator in cell signaling pathways of cancer cell. To investigate the mechanism between cancer cells survival and its EGFR expression, drug selection of cancer cells target therapy, we generated a cell line, 9L-EGFR, which stably expressed human EGFR; the parental rat glioma cell line, 9L, does not contain endogenous EGFR message or protein. Our results show that 9L-EGFR cells had high levels of EGFR on their cell surface by using RT-PCR, Western analysis and Flow cytometry analysis. The EGFR transfected into 9L cells was capable of being activated by EGF, in which either phosphorylated (p-EGFR) or total (EGFR) was showed by Western blot. This investigation may contribute to the further studies of cancer cells bearing EGFR.

  6. Regulation of cyclooxygenase-2 expression in rat oviductal epithelial cells: Evidence for involvement of GPR30/Src kinase-mediated EGFR signaling.

    Science.gov (United States)

    Popli, Pooja; Sirohi, Vijay Kumar; Manohar, Murli; Shukla, Vinay; Kaushal, Jyoti Bala; Gupta, Kanchan; Dwivedi, Anila

    2015-11-01

    The oviduct plays a crucial role in female reproduction by regulating gamete transport, providing a specific microenvironment for fertilization and early embryonic development. Cyclooxygenase (COX)-derived prostaglandins play essential role in carrying out these oviduct-specific functions. Estrogen upregulates COX-2 expression in rat oviduct; however, the mechanisms responsible for regulation of COX-2 expression in rat oviductal epithelial cells (OECs) remain unclear. In the present study, we proposed that estrogen induces COX-2 expression via G-protein coupled receptor i.e., GPR30 in OECs. To investigate this hypothesis, we examined the effects of E2-BSA, ICI 182,780, GPR30 agonist and GPR30 antagonist on COX-2 expression and explored potential signaling pathway leading to COX-2 expression. Co-localization experiments revealed GPR30 to be primarily located in the peri-nuclear space, which was also the site of E2-BSA-fluorescein isothiocyanate (E2-BSA-FITC) binding. The E2-BSA induced-COX-2 and prostaglandin release were subjected to regulation by both EGFR and PI3K signaling as inhibitors of c-Src kinase (PP2), EGFR (EGFR inhibitor) and PI-3 kinase (LY294002) attenuated E2-BSA mediated effect. These results suggest that EGFR transactivation leading to activation of PI-3K/Akt pathway participates in COX-2 expression in rat OECs. Interestingly, E2-BSA induced COX-2 expression and subsequent prostaglandin release were abolished by NF-κB inhibitor. In addition, E2-BSA induced the nuclear translocation of p65-NF-κB and up-regulated the NF-κB promoter activity in rat OECs. Taken together, results demonstrated that E2-BSA induced the COX-2 expression and consequent PGE2 and PGF2α release in rat OECs. These effects are mediated through GPR30-derived EGFR transactivation and PI-3K/Akt cascade leading to NF-κB activation.

  7. Alpha-particle emitting 213Bi-anti-EGFR immunoconjugates eradicate tumor cells independent of oxygenation.

    Directory of Open Access Journals (Sweden)

    Christian Wulbrand

    Full Text Available Hypoxia is a central problem in tumor treatment because hypoxic cells are less sensitive to chemo- and radiotherapy than normoxic cells. Radioresistance of hypoxic tumor cells is due to reduced sensitivity towards low Linear Energy Transfer (LET radiation. High LET α-emitters are thought to eradicate tumor cells independent of cellular oxygenation. Therefore, the aim of this study was to demonstrate that cell-bound α-particle emitting (213Bi immunoconjugates kill hypoxic and normoxic CAL33 tumor cells with identical efficiency. For that purpose CAL33 cells were incubated with (213Bi-anti-EGFR-MAb or irradiated with photons with a nominal energy of 6 MeV both under hypoxic and normoxic conditions. Oxygenation of cells was checked via the hypoxia-associated marker HIF-1α. Survival of cells was analysed using the clonogenic assay. Cell viability was monitored with the WST colorimetric assay. Results were evaluated statistically using a t-test and a Generalized Linear Mixed Model (GLMM. Survival and viability of CAL33 cells decreased both after incubation with increasing (213Bi-anti-EGFR-MAb activity concentrations (9.25 kBq/ml-1.48 MBq/ml and irradiation with increasing doses of photons (0.5-12 Gy. Following photon irradiation survival and viability of normoxic cells were significantly lower than those of hypoxic cells at all doses analysed. In contrast, cell death induced by (213Bi-anti-EGFR-MAb turned out to be independent of cellular oxygenation. These results demonstrate that α-particle emitting (213Bi-immunoconjugates eradicate hypoxic tumor cells as effective as normoxic cells. Therefore, (213Bi-radioimmunotherapy seems to be an appropriate strategy for treatment of hypoxic tumors.

  8. Opposing effects of inhibitors of Aurora-A and EGFR in Autosomal Dominant Polycystic Kidney Disease (ADPKD

    Directory of Open Access Journals (Sweden)

    Anna S Nikonova

    2015-10-01

    Full Text Available Aurora-A kinase (AURKA overexpression in numerous tumors induces aneuploidy, in part because of cytokinetic defects. Alisertib and other small-molecule inhibitors targeting AURKA are effective in some patients as monotherapies or combination therapies. EGFR pro-proliferative signaling activity is commonly elevated in cancer, and the EGFR inhibitor erlotinib is commonly used as a standard of care agent for cancer. An erlotinib/alisertib combination therapy is currently under assessment in clinical trials, following pre-clinical studies that indicated synergy of these drugs in cancer. We were interested in further exploring the activity of this drug combination. Beyond well-established functions for AURKA in mitotic progression, additional non-mitotic AURKA functions include control of ciliary stability and calcium signaling. Interestingly, alisertib exacerbates the disease phenotype in mouse models for autosomal dominant polycystic kidney disease (ADPKD, a common inherited syndrome induced by aberrant signaling from PKD1 and PKD2, cilia-localized proteins that have calcium channel activity. EGFR is also more active in ADPKD, making erlotinib also of potential interest in this disease setting. In this study, we have explored the interaction of alisertib and erlotinib in an ADPKD model. These experiments indicated erlotinib restrained cystogenesis, opposing alisertib action. Erlotinib also interacted with alisertib to regulate proliferative signaling proteins, albeit in a complicated manner. Results suggest a nuanced role of AURKA signaling in different pathogenic conditions and inform the clinical use of AURKA inhibitors in cancer patients with comorbidities.

  9. Matrine derivative WM130 inhibits hepatocellular carcinoma by suppressing EGFR/ERK/MMP-2 and PTEN/AKT signaling pathways.

    Science.gov (United States)

    Qian, Liqiang; Liu, Yan; Xu, Yang; Ji, Weidan; Wu, Qiuye; Liu, Yongjing; Gao, Quangen; Su, Changqing

    2015-11-01

    Matrine, a sophora alkaloid, has been demonstrated to exert antitumor effects on many types of cancer. However, its bioactivity is weak and its potential druggability is low. We modified the structure of matrine and obtained a new matrine derivative, WM130 (C30N4H40SO5F), which exhibited better pharmacological activities than matrine. In this study, we investigated the antitumor activity and the underlying mechanisms of WM130 on hepatocellular carcinoma (HCC) cells in vitro and in vivo, and found that WM130 inhibited the proliferation, invasion, migration and induced apoptosis of HCC cells in a dose-dependent manner. Furthermore, after treatment with WM130, the expressions of p-EGFR, p-ERK, p-AKT, MMP-2 and the ratio of Bcl-2/Bax were significantly down-regulated, whereas the expression of PTEN was increased in HCC cells. Moreover, WM130 inhibited Huh-7 xenograft tumor growth in a dose-dependent manner after intravenous administration. Immunohistochemistry results demonstrated that WM130 treatment resulted in down-regulation of p-EGFR, MMP-2, and Ki67 and up-regulation of PTEN. The findings indicated that WM130 could inhibit cell proliferation, invasion, migration and induced apoptosis in HCC cells by suppressing EGFR/ERK/MMP-2 and PTEN/AKT signaling pathways and may be a novel effective candidate for HCC treatment.

  10. Biosynthesis of the halogenated auxin, 4-chloroindole-3-acetic acid.

    Science.gov (United States)

    Tivendale, Nathan D; Davidson, Sandra E; Davies, Noel W; Smith, Jason A; Dalmais, Marion; Bendahmane, Abdelhafid I; Quittenden, Laura J; Sutton, Lily; Bala, Raj K; Le Signor, Christine; Thompson, Richard; Horne, James; Reid, James B; Ross, John J

    2012-07-01

    Seeds of several agriculturally important legumes are rich sources of the only halogenated plant hormone, 4-chloroindole-3-acetic acid. However, the biosynthesis of this auxin is poorly understood. Here, we show that in pea (Pisum sativum) seeds, 4-chloroindole-3-acetic acid is synthesized via the novel intermediate 4-chloroindole-3-pyruvic acid, which is produced from 4-chlorotryptophan by two aminotransferases, TRYPTOPHAN AMINOTRANSFERASE RELATED1 and TRYPTOPHAN AMINOTRANSFERASE RELATED2. We characterize a tar2 mutant, obtained by Targeting Induced Local Lesions in Genomes, the seeds of which contain dramatically reduced 4-chloroindole-3-acetic acid levels as they mature. We also show that the widespread auxin, indole-3-acetic acid, is synthesized by a parallel pathway in pea. PMID:22573801

  11. SAGA complex components and acetate repression in Aspergillus nidulans.

    Science.gov (United States)

    Georgakopoulos, Paraskevi; Lockington, Robin A; Kelly, Joan M

    2012-11-01

    Alongside the well-established carbon catabolite repression by glucose and other sugars, acetate causes repression in Aspergillus nidulans. Mutations in creA, encoding the transcriptional repressor involved in glucose repression, also affect acetate repression, but mutations in creB or creC, encoding components of a deubiquitination system, do not. To understand the effects of acetate, we used a mutational screen that was similar to screens that uncovered mutations in creA, creB, and creC, except that glucose was replaced by acetate to identify mutations that were affected for repression by acetate but not by glucose. We uncovered mutations in acdX, homologous to the yeast SAGA component gene SPT8, which in growth tests showed derepression for acetate repression but not for glucose repression. We also made mutations in sptC, homologous to the yeast SAGA component gene SPT3, which showed a similar phenotype. We found that acetate repression is complex, and analysis of facA mutations (lacking acetyl CoA synthetase) indicates that acetate metabolism is required for repression of some systems (proline metabolism) but not for others (acetamide metabolism). Although plate tests indicated that acdX- and sptC-null mutations led to derepressed alcohol dehydrogenase activity, reverse-transcription quantitative real-time polymerase chain reaction showed no derepression of alcA or aldA but rather elevated induced levels. Our results indicate that acetate repression is due to repression via CreA together with metabolic changes rather than due to an independent regulatory control mechanism.

  12. Refining EGFR-monoclonal antibody treatment in colorectal cancer

    NARCIS (Netherlands)

    Krens, Lisanne Laura

    2015-01-01

    The use of the epidermal growth factor receptor (EGFR) antibodies cetuximab and panitumumab is limited to colorectal cancer (CRC) patients with KRAS wild type tumors and more recently in RAS wild type only. After having become chemotherapy refractory, treatment options are limited for this substanti

  13. Acetate catabolism by Methanosarcina barkeri

    International Nuclear Information System (INIS)

    Cell suspensions of Methanosarcina barkeri convert the carboxyl and methyl group carbons of acetate to carbon dioxide and methane at pH 6 under an atmosphere of 100% CO2. The rate of loss of radioactivity from [1-14C]acetate was over three times greater than that from [2-14C]acetate under these conditions. Control experiments with both labeled substrates present showed that the rates were additive. Addition of a high level of 2-bromoethanesulfonate to selectively inhibit methane formation largely inhibited release of 14C from methyl-labeled acetate but only marginally decreased the rate of loss from [1-14C]acetate. Thus, in the absence of the inhibitor loss of 14C from [1-14C]acetate likely reflects an isotopic exchange reaction with CO2 superimposed on the overall conversion of acetate to CO2 and CH4. The exchange reaction was inhibited by uncouplers such as 2,4-dinitrophenol, CCCP, and FCCP. Cells permeabilized by treatment with nonionic detergents or disrupted by passage through a French pressure cell failed to catalyze the exchange reaction. Exchange activity was not restored by addition of ATP or by use of [1-14C]acetyl CoA as substrate. No evidence for involvement of carbon monoxide dehydrogenase in the exchange was found in these experiments when CO2 was replaced by CO. However, the soluble extracts retained the ability to convert acetate to methane in the presence of H2 and ATP

  14. [Cerebrospinal fluid pressure studies after the intravenous administration of the steroid narcotic, alphaxolone + alphadolone acetate (Althesin)].

    Science.gov (United States)

    Ekhart, E; List, W F; Vadon, P; Oberbauer, R

    1979-09-30

    The effect of alphaxalon + alphadolon-acetate on cerebrospinal fluid pressure (CSFP), mean arterial blood pressure (MPA), heart rate (BMP) and blood gases was investigated in 18 patients. Cerebral perfusion pressure (CPP) was calculated from the difference MAP minus CSFP. Alphaxalon + alphadolon-acetate lowered the normal CSFP and normalized ketamin induced increase of CSFP. Premedication with alphaxalon + alphadolon-acetate delayed the ketamin induced increase of CSFP, which returned to norm after a second dose of alphaxalon + alphadolon-acetate. This effect was seen despite elevation of pCO2 in all patients breathing spontaneously.

  15. A high expression EGFR/cell membrane chromatography and online high performance liquid chromatography/mass spectrometry method for screening EGFR antagonists from Rhizoma Polygoni Cuspidati

    OpenAIRE

    Meng Sun; Yan-min Zhang; Jie Zhang; Si-cen Wang; Lang-chong He

    2011-01-01

    The epidermal growth factor receptors (EGFRs) in some tumor cells are significant targets for drug discovery. In this work, we have developed an EGFR cell membrane chromatography and online high performance liquid chromatography/mass spectrometry system for screening active component from Rhizoma Polygoni Cuspidati. As a result, resveratrol from Rhizoma Polygoni Cuspidati was found to be the active component acting on EGFR like gefitinib. There was a good relationship between their inhibiting...

  16. Acetic acid enhances endurance capacity of exercise-trained mice by increasing skeletal muscle oxidative properties.

    Science.gov (United States)

    Pan, Jeong Hoon; Kim, Jun Ho; Kim, Hyung Min; Lee, Eui Seop; Shin, Dong-Hoon; Kim, Seongpil; Shin, Minkyeong; Kim, Sang Ho; Lee, Jin Hyup; Kim, Young Jun

    2015-01-01

    Acetic acid has been shown to promote glycogen replenishment in skeletal muscle during exercise training. In this study, we investigated the effects of acetic acid on endurance capacity and muscle oxidative metabolism in the exercise training using in vivo mice model. In exercised mice, acetic acid induced a significant increase in endurance capacity accompanying a reduction in visceral adipose depots. Serum levels of non-esterified fatty acid and urea nitrogen were significantly lower in acetic acid-fed mice in the exercised mice. Importantly, in the mice, acetic acid significantly increased the muscle expression of key enzymes involved in fatty acid oxidation and glycolytic-to-oxidative fiber-type transformation. Taken together, these findings suggest that acetic acid improves endurance exercise capacity by promoting muscle oxidative properties, in part through the AMPK-mediated fatty acid oxidation and provide an important basis for the application of acetic acid as a major component of novel ergogenic aids.

  17. Transports of acetate and haloacetate in Burkholderia species MBA4 are operated by distinct systems

    Directory of Open Access Journals (Sweden)

    Su Xianbin

    2012-11-01

    Full Text Available Abstract Background Acetate is a commonly used substrate for biosynthesis while monochloroacetate is a structurally similar compound but toxic and inhibits cell metabolism by blocking the citric acid cycle. In Burkholderia species MBA4 haloacetate was utilized as a carbon and energy source for growth. The degradation of haloacid was mediated by the production of an inducible dehalogenase. Recent studies have identified the presence of a concomitantly induced haloacetate-uptake activity in MBA4. This uptake activity has also been found to transport acetate. Since acetate transporters are commonly found in bacteria it is likely that haloacetate was transported by such a system in MBA4. Results The haloacetate-uptake activity of MBA4 was found to be induced by monochloroacetate (MCA and monobromoacetate (MBA. While the acetate-uptake activity was also induced by MCA and MBA, other alkanoates: acetate, propionate and 2-monochloropropionate (2MCPA were also inducers. Competing solute analysis showed that acetate and propionate interrupted the acetate- and MCA- induced acetate-uptake activities. While MCA, MBA, 2MCPA, and butyrate have no effect on acetate uptake they could significantly quenched the MCA-induced MCA-uptake activity. Transmembrane electrochemical potential was shown to be a driving force for both acetate- and MCA- transport systems. Conclusions Here we showed that acetate- and MCA- uptake in Burkholderia species MBA4 are two transport systems that have different induction patterns and substrate specificities. It is envisaged that the shapes and the three dimensional structures of the solutes determine their recognition or exclusion by the two transport systems.

  18. Antitumor and antiangiogenic effect of the dual EGFR and HER-2 tyrosine kinase inhibitor lapatinib in a lung cancer model

    International Nuclear Information System (INIS)

    There is strong evidence demonstrating that activation of epidermal growth factor receptors (EGFRs) leads to tumor growth, progression, invasion and metastasis. Erlotinib and gefitinib, two EGFR-targeted agents, have been shown to be relevant drugs for lung cancer treatment. Recent studies demonstrate that lapatinib, a dual tyrosine kinase inhibitor of EGFR and HER-2 receptors, is clinically effective against HER-2-overexpressing metastatic breast cancer. In this report, we investigated the activity of lapatinib against non-small cell lung cancer (NSCLC). We selected the lung cancer cell line A549, which harbors genomic amplification of EGFR and HER-2. Proliferation, cell cycle analysis, clonogenic assays, and signaling cascade analyses (by western blot) were performed in vitro. In vivo experiments with A549 cells xenotransplanted into nude mice treated with lapatinib (with or without radiotherapy) were also carried out. Lapatinib dramatically reduced cell proliferation (P < 0.0001), DNA synthesis (P < 0.006), and colony formation capacity (P < 0.0001) in A549 cells in vitro. Furthermore, lapatinib induced G1 cell cycle arrest (P < 0.0001) and apoptotic cell death (P < 0.0006) and reduced cyclin A and B1 levels, which are regulators of S and G2/M cell cycle stages, respectively. Stimulation of apoptosis in lapatinib-treated A549 cells was correlated with increased cleaved PARP, active caspase-3, and proapoptotic Bak-1 levels, and reduction in the antiapoptic IAP-2 and Bcl-xL protein levels. We also demonstrate that lapatinib altered EGFR/HER-2 signaling pathways reducing p-EGFR, p-HER-2, p-ERK1/2, p-AKT, c-Myc and PCNA levels. In vivo experiments revealed that A549 tumor-bearing mice treated with lapatinib had significantly less active tumors (as assessed by PET analysis) (P < 0.04) and smaller in size than controls. In addition, tumors from lapatinib-treated mice showed a dramatic reduction in angiogenesis (P < 0.0001). Overall, these data suggest that lapatinib

  19. EGFR and HER2 expression in advanced biliary tract cancer

    Institute of Scientific and Technical Information of China (English)

    Jan Harder; Oliver Waiz; Florian Otto; Michael Geissler; Manfred Olschewski; Brigitte Weinhold; Hubert E Blum; Annette Schmitt-Graeff; Oliver G Opitz

    2009-01-01

    AIM: To analyze the pathogenetic role and potential clinical usefulness of the epidermal growth factor receptor (EGFR) and the human epidermal growth factor receptor 2 (HER2) in patients with advanced biliary tract cancer (BTC). METHODS: EGFR and HER2 expression was studied in biopsy samples from 124 patients (51% women;median age 64.8 years), with advanced BTC diagnosed between 1997 and 2004. Five micrometers sections of paraffin embedded tissue were examined by standard, FDA approved immunohistochemistry. Tumors with scores of 2+ or 3+ for HER2 expression on immunochemistry were additionally tested for HER2 gene amplification by fluorescence in situ hybridisation (FISH).RESULTS: 34/124 patients (27.4%) had gallbladder cancer, 47 (37.9%) had intrahepatic BTC and 43 (34.7%) had extrahepatic or perihilar BTC. EGFR expression was examined in a subset of 56 samples. EGFR expression was absent in 22/56 tumors (39.3%).Of the remaining samples expression was scored as 1+ in 12 (21.5%), 2+ in 13 (23.2%) and 3+ in 9 (16%), respectively. HER2 expression was as follows: score 0 73/124 (58.8%), score 1+ 27/124 (21.8%), score 2+ 21/124 (17%) and score 3+ 4/124 (3.2%). HER2 gene amplification was present in 6/124, resulting in an overall amplification rate of 5%.CONCLUSION: Our data suggest that routine testing and therapeutic targeting of HER2 does not seem to be useful in patients with BTC, while targeting EGFR may be promising.

  20. Therapeutic efficacy and safety of paclitaxel/lonidamine loaded EGFR-targeted nanoparticles for the treatment of multi-drug resistant cancer.

    Science.gov (United States)

    Milane, Lara; Duan, Zhenfeng; Amiji, Mansoor

    2011-01-01

    The treatment of multi-drug resistant (MDR) cancer is a clinical challenge. Many MDR cells over-express epidermal growth factor receptor (EGFR). We exploit this expression through the development of EGFR-targeted, polymer blend nanocarriers for the treatment of MDR cancer using paclitaxel (a common chemotherapeutic agent) and lonidamine (an experimental drug; mitochondrial hexokinase 2 inhibitor). An orthotopic model of MDR human breast cancer was developed in nude mice and used to evaluate the safety and efficacy of nanoparticle treatment. The efficacy parameters included tumor volume measurements from day 0 through 28 days post-treatment, terminal tumor weight measurements, tumor density and morphology assessment through hematoxylin and eosin staining of excised tumors, and immunohistochemistry of tumor sections for MDR protein markers (P-glycoprotein, Hypoxia Inducible Factor, EGFR, Hexokinase 2, and Stem Cell Factor). Toxicity was assessed by tracking changes in animal body weight from day 0 through 28 days post-treatment, by measuring plasma levels of the liver enzymes ALT (Alanine Aminotransferase) and LDH (lactate dehydrogenase), and by white blood cell and platelet counts. In these studies, this nanocarrier system demonstrated superior efficacy relative to combination (paclitaxel/lonidamine) drug solution and single agent treatments in nanoparticle and solution form. The combination nanoparticles were the only treatment group that decreased tumor volume, sustaining this decrease until the 28 day time point. In addition, treatment with the EGFR-targeted lonidamine/paclitaxel nanoparticles decreased tumor density and altered the MDR phenotype of the tumor xenografts. These EGFR-targeted combination nanoparticles were considerably less toxic than solution treatments. Due to the flexible design and simple conjugation chemistry, this nanocarrier system could be used as a platform for the development of other MDR cancer therapies; the use of this system for EGFR

  1. Therapeutic efficacy and safety of paclitaxel/lonidamine loaded EGFR-targeted nanoparticles for the treatment of multi-drug resistant cancer.

    Directory of Open Access Journals (Sweden)

    Lara Milane

    Full Text Available The treatment of multi-drug resistant (MDR cancer is a clinical challenge. Many MDR cells over-express epidermal growth factor receptor (EGFR. We exploit this expression through the development of EGFR-targeted, polymer blend nanocarriers for the treatment of MDR cancer using paclitaxel (a common chemotherapeutic agent and lonidamine (an experimental drug; mitochondrial hexokinase 2 inhibitor. An orthotopic model of MDR human breast cancer was developed in nude mice and used to evaluate the safety and efficacy of nanoparticle treatment. The efficacy parameters included tumor volume measurements from day 0 through 28 days post-treatment, terminal tumor weight measurements, tumor density and morphology assessment through hematoxylin and eosin staining of excised tumors, and immunohistochemistry of tumor sections for MDR protein markers (P-glycoprotein, Hypoxia Inducible Factor, EGFR, Hexokinase 2, and Stem Cell Factor. Toxicity was assessed by tracking changes in animal body weight from day 0 through 28 days post-treatment, by measuring plasma levels of the liver enzymes ALT (Alanine Aminotransferase and LDH (lactate dehydrogenase, and by white blood cell and platelet counts. In these studies, this nanocarrier system demonstrated superior efficacy relative to combination (paclitaxel/lonidamine drug solution and single agent treatments in nanoparticle and solution form. The combination nanoparticles were the only treatment group that decreased tumor volume, sustaining this decrease until the 28 day time point. In addition, treatment with the EGFR-targeted lonidamine/paclitaxel nanoparticles decreased tumor density and altered the MDR phenotype of the tumor xenografts. These EGFR-targeted combination nanoparticles were considerably less toxic than solution treatments. Due to the flexible design and simple conjugation chemistry, this nanocarrier system could be used as a platform for the development of other MDR cancer therapies; the use of this

  2. Re-Treatment with EGFR-TKIs in NSCLC Patients Who Developed Acquired Resistance

    Directory of Open Access Journals (Sweden)

    Wen-Shuo Wu

    2014-06-01

    Full Text Available In the era of personalized medicine, epidermal growth factor receptor (EGFR inhibition with tyrosine kinase inhibitor (TKI has been a mainstay of treatment for non-small cell lung cancer (NSCLC patients with an EGFR mutation. Acquired resistance, especially substitution of methionine for threonine at position 790 (T790M, which has accounted for more than half of the cases, developed inevitably in patients who were previously treated with EGFR-TKI. At present, there is no standard treatment for patients who have developed a resistance to EGFR-TKI. Several strategies have been developed or suggested to treat such patients. This article aimsto review the EGFR-TKI re-treatment strategy and the efficacy of different generations of EGFR-TKIs in patients with acquired resistance to prior EGFR-TKI.

  3. EGFR FISH analysis in colorectal cancer as a tool in selecting patients for antiEGFR monoclonal antibodies therapy

    Directory of Open Access Journals (Sweden)

    Mauro Moroni

    2011-12-01

    Full Text Available The recent introduction of targeted therapies in the treatment of patients with metastatic colorectal cancer (mCRC not only improved efficacy but also toxicity and costs of the therapy, therefore requiring the identification of decision-making tools to select patients who are likely to benefit from them. By now, several studies have demonstrated an association between epidermal growth factor receptor (EGFR non-increased gene copy number, evaluated by fluorescence in situ hybridization (FISH, and resistance to the treatment with antiEGFR monoclonal antibodies (moAbs in patients with mCRC. However, the reproducibility of data by standardization of methods still remains an obstacle to be faced for clinical application of the test. We present a review of studies pertaining EGFR FISH analysis as a predictive test of clinical outcome to the treatment with antiEGFR moAbs in mCRC to point out the existing knowledge and the open questions about this issue.

  4. Consensus for EGFR mutation testing in non-small cell lung cancer: results from a European workshop

    DEFF Research Database (Denmark)

    Pirker, Robert; Herth, Felix J F; Kerr, Keith M;

    2010-01-01

    Activating somatic mutations of the tyrosine kinase domain of epidermal growth factor receptor (EGFR) have recently been characterized in a subset of patients with advanced non-small cell lung cancer (NSCLC). Patients harboring these mutations in their tumors show excellent response to EGFR...... tyrosine kinase inhibitors (EGFR-TKIs). The EGFR-TKI gefitinib has been approved in Europe for the treatment of adult patients with locally advanced or metastatic NSCLC with activating mutations of the EGFR TK. Because EGFR mutation testing is not yet well established across Europe, biomarker......-directed therapy only slowly emerges for the subset of NSCLC patients most likely to benefit: those with EGFR mutations....

  5. Zinc Acetate Immobilized on Mesoporous Materials by Acetate Ionic Liquids as Catalysts for Vinyl Acetate Synthesis

    Directory of Open Access Journals (Sweden)

    Hang Xu

    2015-01-01

    Full Text Available Ionic liquid containing active ingredient Zn(CH3COO2 was loaded in mesoporous silica gel to form supported ionic liquids catalyst (SILC which was used to synthesize vinyl acetate monomer (VAM. SILC was characterized by 1HNMR, FT-IR, TGA, BET, and N2 adsorption/desorption and the acetylene method was used to evaluate SILC catalytic activity and stability in fixed reactor. The result shows that 1-allyl-3-acetic ether imidazole acetate ionic liquid is successfully fixed within mesoporous channel of silica gel. The average thickness of ionic liquid catalyst layer is about 1.05 nm. When the catalytic temperature is 195°C, the acetic acid (HAc conversion is 10.9% with 1.1 g vinyl acetate yield and 98% vinyl acetate (VAc selectivity. The HAc conversion is increased by rise of catalytic temperature and molar ratio of C2H2 : HAc and decreased by mass space velocity (WHSV. The catalyst activity is not significantly reduced within 7 days and VAc selectivity has a slight decrease.

  6. EGFR kinase-dependent and kinase-independent roles in clear cell renal cell carcinoma.

    Science.gov (United States)

    Cossu-Rocca, Paolo; Muroni, Maria R; Sanges, Francesca; Sotgiu, Giovanni; Asunis, Anna; Tanca, Luciana; Onnis, Daniela; Pira, Giovanna; Manca, Alessandra; Dore, Simone; Uras, Maria G; Ena, Sara; De Miglio, Maria R

    2016-01-01

    Epidermal growth factor receptor (EGFR) is associated with progression of many epithelial malignancies and represents a significant therapeutic target. Although clear cell renal cell carcinoma (CCRCC) has been widely investigated for EGFR molecular alterations, genetic evidences of EGFR gene activating mutations and/or gene amplification have been rarely confirmed in the literature. Therefore, until now EGFR-targeted therapies in clinical trials have been demonstrated unsuccessful. New evidence has been given about the interactions between EGFR and the sodium glucose co-transporter-1 (SGLT1) in maintaining the glucose basal intracellular level to favour cancer cell growth and survival; thus a new functional role may be attributed to EGFR, regardless of its kinase activity. To define the role of EGFR in CCRCC an extensive investigation of genetic changes and functional kinase activities was performed in a series of tumors by analyzing the EGFR mutational status and expression profile, together with the protein expression of downstream signaling pathways members. Furthermore, we investigated the co-expression of EGFR and SGLT1 proteins and their relationships with clinic-pathological features in CCRCC. EGFR protein expression was identified in 98.4% of CCRCC. Furthermore, it was described for the first time that SGLT1 is overexpressed in CCRCC (80.9%), and that co-expression with EGFR is appreciable in 79.4% of the tumours. Moreover, the activation of downstream EGFR pathways was found in about 79.4% of SGLT1-positive CCRCCs. The mutational status analysis of EGFR failed to demonstrate mutations on exons 18 to 24 and the presence of EGFR-variantIII (EGFRvIII) in all CCRCCs analyzed. FISH analysis revealed absence of EGFR amplification, and high polysomy of chromosome 7. Finally, the EGFR gene expression profile showed gene overexpression in 38.2% of CCRCCs. Our study contributes to define the complexity of EGFR role in CCRCC, identifying its bivalent kinase

  7. EGFR kinase-dependent and kinase-independent roles in clear cell renal cell carcinoma.

    Science.gov (United States)

    Cossu-Rocca, Paolo; Muroni, Maria R; Sanges, Francesca; Sotgiu, Giovanni; Asunis, Anna; Tanca, Luciana; Onnis, Daniela; Pira, Giovanna; Manca, Alessandra; Dore, Simone; Uras, Maria G; Ena, Sara; De Miglio, Maria R

    2016-01-01

    Epidermal growth factor receptor (EGFR) is associated with progression of many epithelial malignancies and represents a significant therapeutic target. Although clear cell renal cell carcinoma (CCRCC) has been widely investigated for EGFR molecular alterations, genetic evidences of EGFR gene activating mutations and/or gene amplification have been rarely confirmed in the literature. Therefore, until now EGFR-targeted therapies in clinical trials have been demonstrated unsuccessful. New evidence has been given about the interactions between EGFR and the sodium glucose co-transporter-1 (SGLT1) in maintaining the glucose basal intracellular level to favour cancer cell growth and survival; thus a new functional role may be attributed to EGFR, regardless of its kinase activity. To define the role of EGFR in CCRCC an extensive investigation of genetic changes and functional kinase activities was performed in a series of tumors by analyzing the EGFR mutational status and expression profile, together with the protein expression of downstream signaling pathways members. Furthermore, we investigated the co-expression of EGFR and SGLT1 proteins and their relationships with clinic-pathological features in CCRCC. EGFR protein expression was identified in 98.4% of CCRCC. Furthermore, it was described for the first time that SGLT1 is overexpressed in CCRCC (80.9%), and that co-expression with EGFR is appreciable in 79.4% of the tumours. Moreover, the activation of downstream EGFR pathways was found in about 79.4% of SGLT1-positive CCRCCs. The mutational status analysis of EGFR failed to demonstrate mutations on exons 18 to 24 and the presence of EGFR-variantIII (EGFRvIII) in all CCRCCs analyzed. FISH analysis revealed absence of EGFR amplification, and high polysomy of chromosome 7. Finally, the EGFR gene expression profile showed gene overexpression in 38.2% of CCRCCs. Our study contributes to define the complexity of EGFR role in CCRCC, identifying its bivalent kinase

  8. 21 CFR 73.2396 - Lead acetate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Lead acetate. 73.2396 Section 73.2396 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2396 Lead acetate. (a) Identity. The color additive lead acetate is the trihydrate of lead (2+) salt of acetic acid. The color additive has the chemical formula...

  9. 27 CFR 21.107 - Ethyl acetate.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Ethyl acetate. 21.107....107 Ethyl acetate. (a) 85 percent ester: (1) Acidity (as acetic acid). Not more than 0.015 percent by...); for incorporation by reference, see § 21.6(b).) When 100 ml of ethyl acetate are distilled by...

  10. 21 CFR 173.228 - Ethyl acetate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethyl acetate. 173.228 Section 173.228 Food and..., Lubricants, Release Agents and Related Substances § 173.228 Ethyl acetate. Ethyl acetate (CAS Reg. No. 141-78... the specifications of the Food Chemicals Codex, 1 (Ethyl Acetate; p. 372, 3d Ed., 1981), which...

  11. Co-targeting EGFR and survivin with a bivalent aptamer-dual siRNA chimera effectively suppresses prostate cancer.

    Science.gov (United States)

    Liu, Hong Yan; Yu, Xiaolin; Liu, Haitao; Wu, Daqing; She, Jin-Xiong

    2016-01-01

    Current targeted therapies using small kinase inhibitors and antibodies have limited efficacy in treating prostate cancer (PCa), a leading cause of cancer death in American men. We have developed a novel strategy by engineering an RNA-based aptamer-siRNA chimera, in which a bivalent aptamer specifically binds prostate-specific membrane antigen (PSMA) via an antibody-like structure to promote siRNA internalization in PCa cells, and two siRNAs specific to EGFR and survivin are fused between two aptamers. The chimera is able to inhibit EGFR and survivin simultaneously and induce apoptosis effectively in vitro and in vivo. In the C4-2 PCa xenograft model, the treatment with the chimera significantly suppresses tumor growth and angiogenesis. The inhibition of angiogenesis is mediated by an EGFR-HIF1α-VEGF-dependent mechanism. Our results support that the bivalent aptamer-driven delivery of two siRNAs could be a new combination therapeutic strategy to effectively inhibit multiple and conventionally "undruggable" targets. PMID:27456457

  12. Molecular genetic alterations in egfr CA-SSR-1 microsatellite and egfr copy number changes are associated with aggressiveness in thymoma

    Science.gov (United States)

    Conti, Salvatore; Gallo, Enzo; Sioletic, Stefano; Facciolo, Francesco; Palmieri, Giovannella; Lauriola, Libero; Evoli, Amelia; Martucci, Robert; Di Benedetto, Anna; Novelli, Flavia; Giannarelli, Diana; Deriu, Gloria; Granone, Pierluigi; Ottaviano, Margaret; Muti, Paola; Pescarmona, Edoardo

    2016-01-01

    Background The key role of egfr in thymoma pathogenesis has been questioned following the failure in identifying recurrent genetic alterations of egfr coding sequences and relevant egfr amplification rate. We investigated the role of the non-coding egfr CA simple sequence repeat 1 (CA-SSR-1) in a thymoma case series. Methods We used sequencing and egfr-fluorescence in situ hybridization (FISH) to genotype 43 thymomas; (I) for polymorphisms and somatic loss of heterozygosity of the non-coding egfr CA-SSR-1 microsatellite and (II) for egfr gene copy number changes. Results We found two prevalent CA-SSR-1 genotypes: a homozygous 16 CA repeat and a heterozygous genotype, bearing alleles with 16 and 20 CA repeats. The average combined allele length was correlated with tumor subtype: shorter sequences were significantly associated with the more aggressive WHO thymoma subtype group including B2/B3, B3 and B3/C histotypes. Four out of 29 informative cases analysed for somatic CA-SSR-1 loss of heterozygosity showed allelic imbalance (AI), 3/4 with loss of the longer allele. By egfr-FISH analysis, 9 out of 33 cases were FISH positive. Moreover, the two integrated techniques demonstrated that 3 out of 4 CA-SSR-1-AI positive cases with short allele relative prevalence showed significantly low or high chromosome 7 “polysomy”/increased gene copy number by egfr-FISH. Conclusions Our molecular and genetic and follow up data indicated that CA-SSR-1-allelic imbalance with short allele relative prevalence significantly correlated with EGFR 3+ immunohistochemical score, increased egfr Gene Copy Number, advanced stage and with relapsing/metastatic behaviour in thymomas. PMID:27076933

  13. Identification of potent EGFR inhibitors from TCM Database@Taiwan.

    Directory of Open Access Journals (Sweden)

    Shun-Chieh Yang

    2011-10-01

    Full Text Available Overexpression of epidermal growth factor receptor (EGFR has been associated with cancer. Targeted inhibition of the EGFR pathway has been shown to limit proliferation of cancerous cells. Hence, we employed Traditional Chinese Medicine Database (TCM Database@Taiwan (http://tcm.cmu.edu.tw to identify potential EGFR inhibitor. Multiple Linear Regression (MLR, Support Vector Machine (SVM, Comparative Molecular Field Analysis (CoMFA, and Comparative Molecular Similarities Indices Analysis (CoMSIA models were generated using a training set of EGFR ligands of known inhibitory activities. The top four TCM candidates based on DockScore were 2-O-caffeoyl tartaric acid, Emitine, Rosmaricine, and 2-O-feruloyl tartaric acid, and all had higher binding affinities than the control Iressa®. The TCM candidates had interactions with Asp855, Lys716, and Lys728, all which are residues of the protein kinase binding site. Validated MLR (r² = 0.7858 and SVM (r² = 0.8754 models predicted good bioactivity for the TCM candidates. In addition, the TCM candidates contoured well to the 3D-Quantitative Structure-Activity Relationship (3D-QSAR map derived from the CoMFA (q² = 0.721, r² = 0.986 and CoMSIA (q² = 0.662, r² = 0.988 models. The steric field, hydrophobic field, and H-bond of the 3D-QSAR map were well matched by each TCM candidate. Molecular docking indicated that all TCM candidates formed H-bonds within the EGFR protein kinase domain. Based on the different structures, H-bonds were formed at either Asp855 or Lys716/Lys728. The compounds remained stable throughout molecular dynamics (MD simulation. Based on the results of this study, 2-O-caffeoyl tartaric acid, Emitine, Rosmaricine, and 2-O-feruloyl tartaric acid are suggested to be potential EGFR inhibitors.

  14. 21 CFR 184.1185 - Calcium acetate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Calcium acetate. 184.1185 Section 184.1185 Food and... Substances Affirmed as GRAS § 184.1185 Calcium acetate. (a) Calcium acetate (Ca (C2H3O2)2, CAS Reg. No. 62-54-4), also known as acetate of lime or vinegar salts, is the calcium salt of acetic acid. It may...

  15. 40 CFR 721.10001 - 2-Ethoxyethanol, 2-ethoxyethanol acetate, 2-methoxyethanol, and 2-methoxyethanol acetate.

    Science.gov (United States)

    2010-07-01

    ... acetate, 2-methoxyethanol, and 2-methoxyethanol acetate. 721.10001 Section 721.10001 Protection of...-ethoxyethanol acetate, 2-methoxyethanol, and 2-methoxyethanol acetate. (a) Chemical substances and significant...-80-5), 2-ethoxyethanol acetate (CAS No. 111-15-9), 2-methoxyethanol (CAS No. 109-86-4), and...

  16. Anti-inflammatory effects of alpinone 3-acetate from Alpinia japonica seeds.

    Science.gov (United States)

    Kakegawa, Tomohito; Miyazaki, Aya; Yasukawa, Ken

    2016-07-01

    We aimed to investigate the bioactive components of Alpinia japonica as anti-inflammatory compounds using searches of the Alpinia genus, and subsequently demonstrated that alpinone 3-acetate markedly inhibits 12-O-tetradecanoyiphorbol 13-acetate-induced inflammation in a mouse model of ear edema. To assess other bioactivities of alpinone 3-acetate, we performed translatome analyses and compared them with those of hydrocortisone. Polysome-associated mRNAs were prepared from alpinone 3-acetate- or hydrocortisone-treated and control cells from 12-O-tetradecanoyiphorbol 13-acetate-induced THP-1-derived macrophages cultured in the presence of Escherichia coli O-111 lipopolysaccharide. Subsequent microarray analysis revealed that alpinone 3-acetate and hydrocortisone upregulated and downregulated the same 155 and 41 genes, respectively. Moreover, direct comparisons of translationally regulated genes indicated 5 and 10 gene probes that were upregulated and downregulated by alpinone 3-acetate and hydrocortisone, respectively. In conclusion, assays of 12-O-tetradecanoyiphorbol 13-acetate-induced inflammation ear edema in mice and polysome profiling of alpinone 3-acetate bioactivities indicated similar medicinal possibilities to those of hydrocortisone. PMID:27137785

  17. Coexpression of EGFR and CXCR4 predicts poor prognosis in resected pancreatic ductal adenocarcinoma.

    Directory of Open Access Journals (Sweden)

    Huanwen Wu

    Full Text Available Epidermal growth factor receptor (EGFR is highly expressed in pancreatic ductal adenocarcinoma (PDAC and is involved in tumorigenesis and development. However, EGFR expression alone has limited clinical and prognostic significance. Recently, the cross-talk between EGFR and G-protein-coupled chemokine receptor CXCR4 has become increasingly recognized.In the present study, immunohistochemical staining of EGFR and CXCR4 was performed on paraffin-embedded specimens from 131 patients with surgically resected PDAC. Subsequently, the associations between EGFR expression, CXCR4 expression, EGFR/CXCR4 coexpression and clinicopathologic factors were assessed, and survival analyses were performed.In total, 64 (48.9% patients expressed EGFR, 68 (51.9% expressed CXCR4, and 33 (25.2% coexpressed EGFR and CXCR4. No significant association between EGFR and CXCR4 expression was observed (P = 0.938. EGFR expression significantly correlated with tumor differentiation (P = 0.031, whereas CXCR4 expression significantly correlated with lymph node metastasis (P = 0.001. EGFR/CXCR4 coexpression was significantly associated with lymph node metastasis (P = 0.026, TNM stage (P = 0.048, and poor tumor differentiation (P = 0.004. By univariate survival analysis, both CXCR4 expression and EGFR/CXCR4 coexpression were significant prognostic factors for poor disease-free survival (DFS and overall survival (OS. Moreover, EGFR/CXCR4 coexpression significantly increased the hazard ratio for both recurrence and death compared with EGFR or CXCR4 protein expression alone. Multivariate survival analysis demonstrated that EGFR/CXCR4 coexpression was an independent prognostic factor for DFS (HR = 2.33, P<0.001 and OS (HR = 2.48, P = 0.001.In conclusion, our data indicate that although EGFR expression alone has limited clinical and prognostic significance, EGFR/CXCR4 coexpression identified a subset of PDAC patients with more aggressive tumor characteristics and a significantly worse

  18. Role of EGFR mutations in lung cancers: prognosis and tumor chemosensitivity.

    Science.gov (United States)

    Suda, Kenichi; Mitsudomi, Tetsuya

    2015-08-01

    Lung cancers with an epidermal growth factor receptor (EGFR) gene mutation account for ~40 % of adenocarcinomas in East Asians and ~15 % of those in Caucasians and African Americans, which makes them one of the most common molecularly defined lung cancer subsets. The discriminative clinical and pathological features of lung cancers with EGFR mutations have been intensively studied, and the predictive role of an EGFR mutation for treatment with EGFR tyrosine kinase inhibitors (EGFR-TKIs) is well established. However, controversial issues remain regarding the clinical and therapeutic implications of EGFR mutations in lung cancers. These include the prognostic impact of the EGFR mutation, its predictive implication for successful treatment with anticancer agents other than EGFR-TKIs, appropriate cytotoxic agents for lung cancers with this mutation, and the chemosensitivity of EGFR-mutation-positive lung cancers after acquisition of resistance to EGFR-TKIs. In this review, we discuss these unanswered but important questions, referring to in vitro studies, basic research, retrospective analyses, and the results of phase III clinical trials. PMID:25983263

  19. Lapatinib, a dual EGFR and HER2 tyrosine kinase inhibitor, downregulates thymidylate synthase by inhibiting the nuclear translocation of EGFR and HER2.

    Directory of Open Access Journals (Sweden)

    Hwang-Phill Kim

    Full Text Available BACKGROUND: Epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI has been shown to exert a synergistic antitumor effect when combined with fluoropyrimidine. This synergy may be attributable to the downregulation of thymidylate synthase (TS, which is frequently overexpressed in fluoropyrimidine-resistant cancer cells. However, the molecular mechanism underlying the downregulation of TS has yet to be clearly elucidated. METHODOLOGY AND PRINCIPAL FINDINGS: In this study, we demonstrate that lapatinib, a dual TKI of EGFR and HER2 downregulates TS via inhibition of the nuclear translocation of EGFR and HER2. From our cDNA microarray experiments, we determined that a variety of nucleotide synthesis-related genes, including TS, were downregulated with lapatinib, and this was apparent in HER2-amplified cells. Targeted and pharmacologic inhibition assays confirmed that the dual inhibition of EGFR and HER2 is required for the more effective reduction of TS as compared to what was observed with gefitinib or trasutuzumab alone. Additionally, we determined that co-transfected EGFR and HER2 activate the TS gene promoter more profoundly than do either EGFR or HER2 alone. The translocation of EGFR and HER2 into the nucleus and the subsequent activation of the TS promoter were inhibited by lapatinib. CONCLUSIONS AND SIGNIFICANCE: These results demonstrate that lapatinib inhibits the nuclear translocation of EGFR and HER2 and downregulates TS, thus sensitizing cancer cells to fluoropyrimidine.

  20. Analysis of EGFR signaling pathway in nasopharyngeal carcinoma cells by quantitative phosphoproteomics

    Directory of Open Access Journals (Sweden)

    He Qiu-Yan

    2011-06-01

    Full Text Available Abstract Background The epidermal growth factor receptor (EGFR is usually overexpressed in nasopharyngeal carcinoma (NPC and is associated with pathogenesis of NPC. However, the downstream signaling proteins of EGFR in NPC have not yet been completely understood at the system level. The aim of this study was identify novel downstream proteins of EGFR signaling pathway in NPC cells. Results We analyzed EGFR-regulated phosphoproteome in NPC CNE2 cells using 2D-DIGE and mass spectrometry analysis after phosphoprotein enrichment. As a result, 33 nonredundant phosphoproteins including five known EGFR-regulated proteins and twenty-eight novel EGFR-regulated proteins in CNE2 were identified, three differential phosphoproteins were selectively validated, and two differential phosphoproteins (GSTP1 and GRB2 were showed interacted with phospho-EGFR. Bioinformatics analysis showed that 32 of 33 identified proteins contain phosphorylation modification sites, and 17 identified proteins are signaling proteins. GSTP1, one of the EGFR-regulated proteins, associated with chemoresistance was analyzed. The results showed that GSTP1 could contribute to paclitaxel resistance in EGF-stimulated CNE2 cells. Furthermore, an EGFR signaling network based on the identified EGFR-regulated phosphoproteins were constructed using Pathway Studio 5.0 software, which includes canonical and novel EGFR-regulated proteins and implicates the possible biological roles for those proteins. Conclusion The data not only can extend our knowledge of canonical EGFR signaling, but also will be useful to understand the molecular mechanisms of EGFR in NPC pathogenesis and search therapeutic targets for NPC.

  1. 5-(Chloromethylquinolin-8-yl acetate

    Directory of Open Access Journals (Sweden)

    Ling-Qian Kong

    2008-08-01

    Full Text Available The title compound, C12H10ClNO2, crystallizes with two independent molecules in the asymmetric unit; these are approximate mirror images of each other. In each molecule, the chloromethyl and acetate groups lie on the same side of the quinoline ring system, with dihedral angles between the ring plane and the plane of the acetate group of 82.0 (1 and −79.2 (1°. The C—C—C—Cl torsion angles for the chloromethyl groups of the two molecules are 80.9 (2 and −83.1 (2°.

  2. Unsuccessful treatment of acromegaly with medroxyprogesterone acetate.

    Science.gov (United States)

    Atkinson, R L; Dimond, R C; Howard, W J; Earll, J M

    1974-09-01

    6 patients with active acromegaly were treated with 10 mg of medroxyprogesterone acetate (MPA) every 6 hours daily for 2 weeks to 6 months. Oral glucose tolerance tests, growth hormone (GH) levels, and insulin tolerance tests (ITT) were done before and during MPA treatment. Basal GH levels varied widely during control and therapy periods; no significant lowering of GH levels occurred during treatment. Carbohydrate tolerance was not significantly affected by MPA therapy, although 5 out of 6 patients had deterioration at least once during treatment. Blood glucose response to ITT was unchanged by MPA. MPA did not affect the clinical features of acromegaly. There was no consistent effect of MPA on insulin-induced or arginine-induced GH secretion. It is concluded that MPA is not an effective agent for treating acromegaly.

  3. Effect of EGFR-TKI retreatment following chemotherapy for advanced non-small cell lung cancer patients who underwent EGFR-TKI

    International Nuclear Information System (INIS)

    Non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR)-activating mutations have higher response rate and more prolonged survival following treatment with single-agent EGFR tyrosine kinase inhibitor (EGFR-TKI) compared with patients with wild-type EGFR. However, all patients treated with reversible inhibitors develop acquired resistance over time. The mechanisms of resistance are complicated. The lack of established therapeutic options for patients after a failed EGFR-TKI treatment poses a great challenge to physicians in managing this group of lung cancer patients. This study evaluates the influence of EGFR-TKI retreatment following chemotherapy after failure of initial EGFR-TKI within at least 6 months on NSCLC patients. The data of 27 patients who experienced treatment failure from their initial use of EGFR-TKI within at least 6 months were analyzed. After chemotherapy, the patients were retreated with EGFR-TKI (gefitinib 250 mg qd or erlotinib 150 mg qd), and the tumor progression was observed. The patients were assessed for adverse events and response to therapy. Targeted tumor lesions were assessed with CT scan. Of the 27 patients who received EGFR-TKI retreatment, 1 (3.7%) patient was observed in complete response (CR), 8 (29.6%) patients in partial response (PR), 14 (51.9%) patients in stable disease (SD), and 4 (14.8%) patients in progressive disease (PD). The disease control rate (DCR) was 85.2% (95% CI: 62%-94%). The median progression-free survival (mPFS) was 6 months (95% CI: 1-29). Of the 13 patients who received the same EGFR-TKI, 1 patient in CR, 3 patients in PR, 8 patients in SD, and 2 patients in PD were observed. The DCR was 84.6%, and the mPFS was 5 months. Of the 14 patients who received another EGFR-TKI, no patient in CR, 6 patients in PR, 6 patients in SD, and 2 patients in PD were observed. The DCR was 85.7%, and the mPFS was 9.5 months. Significant difference was found between the two groups in PFS but not

  4. Effect of EGFR-TKI retreatment following chemotherapy for advanced non-small cell lung cancer patients who under went EGFR-TKI

    Institute of Scientific and Technical Information of China (English)

    Guo-Hao Xia; Ji-Feng Feng; Yun Zeng; Ying Fang; Shao-Rong Yu; Li Wang; Mei-Qi Shi; Wei-Li Sun; Xin-En Huang; Jia Chen

    2014-01-01

    Objective:Non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR)-activating mutations have higher response rate and more prolonged survival following treatment with single-agent EGFR tyrosine kinase inhibitor (EGFR-TKI) compared with patients with wild-type EGFR. However, all patients treated with reversible inhibitors develop acquired resistance over time. hTe mechanisms of resistance are complicated. hTe lack of established therapeutic options for patients atfer a failed EGFR-TKI treatment poses a great challenge to physicians in managing this group of lung cancer patients. hTis study evaluates the inlfuence of EGFR-TKI retreatment following chemotherapy atfer failure of initial EGFR-TKI within at least 6 months on NSCLC patients. Methods:hTe data of 27 patients who experienced treatment failure from their initial use of EGFR-TKI within at least 6 months were analyzed. Atfer chemotherapy, the patients were retreated with EGFR-TKI (geiftinib 250 mg qd or erlotinib 150 mg qd), and the tumor progression was observed. The patients were assessed for adverse events and response to therapy. Targeted tumor lesions were assessed with CT scan. Results:Of the 27 patients who received EGFR-TKI retreatment, 1 (3.7%) patient was observed in complete response (CR), 8 (29.6%) patients in partial response (PR), 14 (51.9%) patients in stable disease (SD), and 4 (14.8%) patients in progressive disease (PD). hTe disease control rate (DCR) was 85.2%(95%CI:62%-94%). hTe median progression-free survival (mPFS) was 6 months (95%CI:1-29). Of the 13 patients who received the same EGFR-TKI, 1 patient in CR, 3 patients in PR, 8 patients in SD, and 2 patients in PD were observed. hTe DCR was 84.6%, and the mPFS was 5 months. Of the 14 patients who received another EGFR-TKI, no patient in CR, 6 patients in PR, 6 patients in SD, and 2 patients in PD were observed. hTe DCR was 85.7%, and the mPFS was 9.5 months. Signiifcant difference was found between the two

  5. IGFBP2 potentiates nuclear EGFR-STAT3 signaling

    OpenAIRE

    Chua, Corrine Yingxuan; Liu, Yuexin; Granberg, Kirsi J.; Hu, Limei; Haapasalo, Hannu; Annala, Matti J.; Cogdell, David E.; Verploegen, Maartje; Moore, Lynette M.; Fuller, Gregory N.; Nykter, Matti; Cavenee, Webster K.; Zhang, Wei

    2015-01-01

    Insulin-like growth factor binding protein 2 (IGFBP2) is a pleiotropic oncogenic protein that has both extracellular and intracellular functions. Despite a clear causal role in cancer development, the tumor-promoting mechanisms of IGFBP2 are poorly understood. The contributions of intracellular IGFBP2 to tumor development and progression are also unclear. Here we present evidence that both exogenous IGFBP2 treatment and cellular IGFBP2 overexpression lead to aberrant activation of EGFR, which...

  6. Molecular mechanisms of the enhanced anti-tumor effect of ionizing radiation by epidermal growth factor receptor (EGFR) blockade: the role of vascular endothelial growth factor (VEGF)

    International Nuclear Information System (INIS)

    Recent studies demonstrating that inhibition of the EGFR enhances the anti-tumor effect of radiation have prompted the commencement of clinical trials of this therapeutic strategy. The mechanisms involved in this interaction remain to be fully established and are potentially important for patient selection, as well as understanding the basis of resistance to this approach. Initial studies with the EGFR tyrosine kinase inhibitor gefitinib (ZD1839, Iressa) used in combination with radiation in A431 xenografts in nude mice demonstrated greater in vivo than in vitro effects. An effect on angiogenesis was suggested by reductions in microvessel staining and VEGF expression in tumors treated with ZD1839. Measurement of VEGF production of cell culture supernatant demonstrated that gefitinib is able to inhibit EGF-stimulated as well as basal VEGF production in A431 cells as well as in other cell lines including head and neck squamous cell carcinoma (SCC-25) and androgen-insensitive prostate cancer (DU145). Signal transduction pathways downstream of the EGF leading to VEGF production were dissected using specific inhibitors of PI3K (LY294002), MAPK (U0126), and p38 Kinase (SB203580) in A431 cells. Inhibition of PI3K reduced EGF stimulated VEGF production. Similarly EGF stimulated HIF-1alpha protein expression was reduced by EGFR inhibition with gefitinib as well as by downstream inhibition of PI3K. Cell lines producingVEGF in a doxycycline-inducible manner (pBIEGFPVEGF165) have been generated to determine the effects of maintaining VEGF expression despite EGFR inhibition. Experiments performed in vivo with these lines to determine if inducible-VEGF expression rescues tumors from the enhanced effects of radiation in combination with EGFR inhibition will be presented

  7. Reciprocal regulation of annexin A2 and EGFR with Her-2 in Her-2 negative and herceptin-resistant breast cancer.

    Directory of Open Access Journals (Sweden)

    Praveenkumar K Shetty

    Full Text Available Alternative survival pathways are commonly seen to be upregulated upon inhibition of receptor tyrosine kinases (RTK, including Her-2. It is established that treatment with Herceptin leads to selective overexpression and activation of epidermal growth factor receptor (EGFR and Src which further contributes to oncogenesis in Herceptin resistant and triple negative breast cancer (TNBC patients. Here, we show a co-regulated upregulation in the expression of Annexin A2 (AnxA2, a known substrate of Src and one of the regulators of EGFR receptor endocytosis, in Herceptin resistant and Her-2 negative breast cancer. Immunohistochemical expression analysis revealed a reciprocal regulation between Her-2 and AnxA2 in breast cancer clinical samples as well as in cell lines as confirmed by protein and RNA analysis. The siRNA and Herceptin mediated downregulation/inhibition of Her-2 in Her-2 amplified cells induced AnxA2 expression and membrane translocation. In this study we report a possible involvement of AnxA2 in maintaining constitutively activated EGFR downstream signaling intermediates and hence in cell proliferation, migration and viability. This effect was consistent in Herceptin resistant JIMT-1 cells as well as in Her-2 negative breast cancer. The siRNA mediated AnxA2 downregulation leads to increased apoptosis, decreased cell viability and migration. Our studies further indicate the role of AnxA2 in EGFR-Src membrane bound signaling complex and ligand induced activation of downstream signaling pathways. Targeting this AnxA2 dependent positive regulation of EGFR signaling cascade may be of therapeutic value in Her-2 negative breast cancer.

  8. Research progress on criteria for discontinuation of EGFR inhibitor therapy

    Directory of Open Access Journals (Sweden)

    Zhuang HQ

    2012-10-01

    Full Text Available Hong-qing Zhuang, Zhi-yong Yuan, Jun Wang, Ping Wang, Lu-jun Zhao, Bai-lin ZhangDepartment of Radiotherapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin Key Laboratory of Cancer Prevention and Therapy, Tianjin Lung Cancer Center, Tianjin, People's Republic of ChinaAbstract: The clinical success of the epidermal growth factor receptor (EGFR tyrosine kinase inhibitors (TKI as therapeutic agents has prompted great interest in their further development and clinical testing for a wide variety of malignancies. However, most studies have focused on the efficacy of TKI, and few studies have been done on the criteria for their discontinuation. The current standard for drug discontinuation is “until progression”, based on change in tumor size. However, tumor size is not related to the gene expression which determines the efficacy of TKI in the final analysis, and it is also difficult to make a thorough and correct prediction based on tumor size when the TKI is discontinued. Nevertheless, clinical evaluation of the criteria for TKI discontinuation is still in its early days. Some promising findings have started to emerge. With the improving knowledge of EGFR and its inhibitors, it is expected that the criteria for discontinuation of EGFR inhibitor therapy will become clearer.Keywords: epidermal growth factor receptor, drug discontinuation, acquired drug-resistance

  9. 中药逆转EGFR-TKIs治疗NSCLC耐药的研究进展%Research Progress in Traditional Chinese Medicine for Altering EGFR-TKIs Resistance

    Institute of Scientific and Technical Information of China (English)

    叶青; 王瑞平

    2016-01-01

    分子靶向药物表皮生长因子受体酪氨酸酶抑制剂(Epidermal growth factor receptor tyrosine kinase inhibitors, EGFR-TKIs)是具有EGFR突变的晚期非小细胞肺癌(NSCLC)的有效治疗手段。然而,大部分患者在接受治疗一段时间后出现获得性耐药,严重阻碍了治疗的顺利进行。中药在逆转EGFR-TKIs耐药已进行了大量的研究,并显示其可行性和可应用性。本文在阐述EGFR-TKIs耐药机制的基础上,综述近年来中药单体和复方逆转EGFR-TKIs耐药的研宄进展。%Lung cancer is one of the main causes of human deaths. Epidermal growth factor receptor tyrosine kinase inhibitors(EGFR-TKIs)is an effective therapy for advanced non-small cell lung cancer(NSCLC)with EGFR mutations. However,resistance to EGFR-TKIs occurred in the majority of patients after months of treatment,which seriously hindered the treatment to be continued. Large amount of research has revealed the feasibility and applicability of traditional Chinese medicine(TCM)in altering EGFR-TKIs resistance. Here,we discussed the EGFR-TKIs-resistance mechanism and reviewed the research progress in TCM for altering EGFR-TKIs resistance .

  10. Electron attachment and electron ionization of acetic acid clusters embedded in helium nanodroplets

    NARCIS (Netherlands)

    da Silva, F. Ferreira; Jaksch, S.; Martins, G.; Dang, H. M.; Dampc, M.; Denifl, S.; Maerk, T. D.; Limao-Vieira, P.; Liu, J.; Yang, S.; Ellis, A. M.; Scheier, P.

    2009-01-01

    The effect of incident electrons on acetic acid clusters is explored for the first time. The acetic acid clusters are formed inside liquid helium nanodroplets and both cationic and anionic products ejected into the gas phase are detected by mass spectrometry. The cation chemistry (induced by electro

  11. Dacomitinib in lung cancer: a "lost generation" EGFR tyrosine-kinase inhibitor from a bygone era?

    Science.gov (United States)

    Ou, Sai-Hong Ignatius; Soo, Ross A

    2015-01-01

    EGFR tyrosine-kinase inhibitors (TKIs) have now been firmly established as the first-line treatment for non-small-cell lung cancer (NSCLC) patients harboring activating EGFR mutations, based on seven prospective randomized Phase III trials. However, despite significantly improved overall response rate and improved median progression-free survival when compared to platinum-doublet chemotherapy, EGFR-mutant NSCLC patients treated with EGFR TKIs invariably progress due to the emergence of acquired resistances, with the gatekeeper T790M mutation accounting for up to 60% of the resistance mechanisms. Second-generation irreversible EGFR TKIs were developed in part to inhibit the T790M mutation, in addition to the common activating EGFR mutations. Dacomitinib is one such second-generation EGFR TKI designed to inhibit both the wild-type (WT) EGFR and EGFR T790M. Afatinib is another second-generation EGR TKI that has been now been approved for the first-line treatment of EGFR-mutant NSCLC patients, while dacomitinib continues to undergo clinical evaluation. We will review the clinical development of dacomitinib from Phase I to Phase III trials, including the two recently published negative large-scale randomized Phase III trials (ARCHER 1009, NCIC-BR-26). Results from another large-scale randomized trial (ARCHER 1050) comparing dacomitinib to gefitinib as first-line treatment of advanced treatment-naïve EGFR-mutant NSCLC patients will soon be available and will serve as the lynchpin trial for the potential approval of dacomitinib in NSCLC. Meanwhile, third-generation EGFR TKIs (eg, CO-1686 [rociletinib], AZ9291, HM61713, EGF816, and ASP8273) that preferentially and potently inhibit EGFR T790M but not WT EGFR are in full-scale clinical development, and some of these EGFR TKIs have received "breakthrough" designation by the US Food and Drug Administration and will likely be approved in late 2015. Given the rapid development of third-generation EGFR TKIs and the approval of

  12. IGF-1R/epithelial-to-mesenchymal transition (EMT) crosstalk suppresses the erlotinib-sensitizing effect of EGFR exon 19 deletion mutations

    Science.gov (United States)

    Vazquez-Martin, Alejandro; Cufí, Sílvia; Oliveras-Ferraros, Cristina; Torres-Garcia, Violeta Zenobia; Corominas-Faja, Bruna; Cuyàs, Elisabet; Bonavia, Rosa; Visa, Joana; Martin-Castillo, Begoña; Barrajón-Catalán, Enrique; Micol, Vicente; Bosch-Barrera, Joaquim; Menendez, Javier A.

    2013-01-01

    Using non-small cell lung carcinoma (NSCLC) cells harboring the erlotinib-sensitizing Epidermal Growth Factor Receptor (EGFR) exon 19 mutation delE746-A750, we developed erlotinib-refractory derivatives in which hyperactive Insulin-like Growth Factor-1 Receptor (IGF-1R) signaling associated with enrichment in epithelial-to-mesenchymal transition (EMT)-related morphological and transcriptional features. We then explored whether an IGF-1R/EMT crosstalk was sufficient to promote erlotinib refractoriness in the absence of second-site EGFR mutations, MET and AXL hyperactivation. Transforming Growth Factor-beta1 (TGFβ1)-induced mesenchymal trans-differentiation was sufficient to impede erlotinib functioning in the presence of drug-sensitive delE746-A750 EGFR mutation. Pharmacological blockade of IGF-1R fully prevented the TGFβ1's ability to activate an EMT protein signature [E-cadherin low/vimentin high]. The sole presence of erlotinib was capable of rapidly activate an IGF-1R-dependent, vimentin-enriched mesenchymal-like phenotype in delE746-A750-mutated epithelial cells. Even if transient, NSCLC cells' intrinsic plasticity to undergo crosstalk between IGF-1R and EMT signaling pathways can sufficiently eliminate the erlotinib-sensitizing effect of highly prevalent EGFR mutations and suggests the urgent need for dual IGF-1R/EMT-targeting strategies to circumvent erlotinib resistance. PMID:23994953

  13. The EGFR family of receptors sensitizes cancer cells towards UV light

    DEFF Research Database (Denmark)

    Petersen, Steffen B.; Neves Petersen, Teresa; Olsen, Birgitte

    2008-01-01

    A combination of bioinformatics, biophysical, advanced laser studies and cell biology lead to the realization that laser-pulsed UV light stops cancer growth and induces apoptosis. We have previously shown that laser-pulsed UV (LP-UV) illumination of two different skin-derived cancer cell lines both...... bridges. The EGF receptor is often overexpressed in cancers and other proliferative skin disorders, it might be possible to significantly reduce the proliferative potential of these cells making them good targets for laser-pulsed UV-light treatment. The discovery that UV light can be used to open...... that are sensitive to UV light lead to the prediction that UV light could modify these receptors permanently and stop cancer proliferation. We hereby show that the EGFR family of receptors has the necessary structural motifs that make this family of proteins highly sensitive to UV light....

  14. Advances in pulmonary fibrosis caused by thoracic radiotherapy combined with EGFR-TKIs%胸部放疗联合 EGFR -TKIs 致肺纤维化的研究进展

    Institute of Scientific and Technical Information of China (English)

    张倩; 乔文波

    2015-01-01

    Thoracic radiotherapy is an important means of local treatment for non -small cell lung cancer (NSCLC).Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs)have the effect of systemic therapy.Studies have shown that NSCLC patients with EGFR exons 19,21 mutation have a synergistic effect in the combination therapy .Radiotherapy activates EGFR signaling pathway ,inducing cell proliferation and DNA damage repair,leading to radiation resistance .Therefore,EGFR-TKIs have the effect in increasing radiosensitivity .Lung injury is one of the most common side effects when the two therapies combined .Studies suggest that radiotherapy combined with EGFR-TKIs may have conflicting functions in the development of pulmonary fibrosis ,the discrep-ancy between these studies may depend on the differences in the experimental systems ,the differences in pulmo-nary fibrosis models,as well as the differences between different species and individuals .Therefore,a more com-plete understanding of the etiology for pulmonary fibrosis is necessary to the development of improved treatments .%胸部放射治疗是非小细胞肺癌(Non-small cell lung cancer,NSCLC)局部治疗的重要手段,而表皮生长因子受体酪氨酸激酶抑制剂( Epidermal growth factor receptor -tyrosine kinase inhibitor ,EGFR-TKIs)具有全身治疗的作用,研究表明EGFR外显子19、21突变阳性的NSCLC患者放疗与EGFR-TKIs联合治疗时具有增效作用。放疗可激活EGFR信号通路,诱导细胞的增殖和DNA损伤修复,从而导致放射抵抗,因此EGFR-TKIs具有增加放疗敏感性的作用。两者联合治疗时最常见的副反应是肺损伤。研究提示放疗联合EGFR-TKIs在肺纤维化发展中具有矛盾作用,这些研究间差异的存在可能是因为实验系统的不同,纤维化模型的差异,以及不同物种和个体间的差异。因此需要对肺纤维化的病因有更完整的理解,以促进治疗进展。

  15. The Potential Value of EGFR and P53 Immunostaining in Tumors of the Urinary Bladder

    Directory of Open Access Journals (Sweden)

    I