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  1. Novel EGFR inhibitors attenuate cardiac hypertrophy induced by angiotensin II.

    Science.gov (United States)

    Peng, Kesong; Tian, Xinqiao; Qian, Yuanyuan; Skibba, Melissa; Zou, Chunpeng; Liu, Zhiguo; Wang, Jingying; Xu, Zheng; Li, Xiaokun; Liang, Guang

    2016-03-01

    Cardiac hypertrophy is an important risk factor for heart failure. Epidermal growth factor receptor (EGFR) has been found to play a role in the pathogenesis of various cardiovascular diseases. The aim of this current study was to examine the role of EGFR in angiotensin II (Ang II)-induced cardiac hypertrophy and identify the underlying molecular mechanisms. In this study, we observed that both Ang II and EGF could increase the phospohorylation of EGFR and protein kinase B (AKT)/extracellular signal-regulated kinase (ERK), and then induce cell hypertrophy in H9c2 cells. Both pharmacological inhibitors and genetic silencing significantly reduced Ang II-induced EGFR signalling pathway activation, hypertrophic marker overexpression, and cell hypertrophy. In addition, our results showed that Ang II-induced EGFR activation is mediated by c-Src phosphorylation. In vivo, Ang II treatment significantly led to cardiac remodelling including cardiac hypertrophy, disorganization and fibrosis, accompanied by the activation of EGFR signalling pathway in the heart tissues, while all these molecular and pathological alterations were attenuated by the oral administration with EGFR inhibitors. In conclusion, the c-Src-dependent EGFR activation may play an important role in Ang II-induced cardiac hypertrophy, and inhibition of EGFR by specific molecules may be an effective strategy for the treatment of Ang II-associated cardiac diseases. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  2. Gallic acid induces apoptosis in EGFR-mutant non-small cell lung cancers by accelerating EGFR turnover.

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    Nam, Boas; Rho, Jin Kyung; Shin, Dong-Myung; Son, Jaekyoung

    2016-10-01

    Gallic acid is a common botanic phenolic compound, which is present in plants and foods worldwide. Gallic acid is implicated in various biological processes such as cell growth and apoptosis. Indeed, gallic acid has been shown to induce apoptosis in many cancer types. However, the molecular mechanisms of gallic acid-induced apoptosis in cancer, particularly lung cancer, are still unclear. Here, we report that gallic acid induces apoptosis in EGFR-mutant non-small cell lung cancer (NSCLC) cells, but not in EGFR-WT NSCLC cells. Treatment with gallic acid resulted in a significant reduction in proliferation and induction of apoptosis, only in EGFR-mutant NSCLC cells. Interestingly, treatment with gallic acid led to a robust decrease in EGFR levels, which is critical for NSCLC survival. Treatment with gallic acid had no significant effect on transcription, but induced EGFR turnover. Indeed, treatment with a proteasome inhibitor dramatically reversed gallic acid-induced EGFR downregulation. Moreover, treatment with gallic acid induced EGFR turnover leading to apoptosis in EGFR-TKI (tyrosine kinase inhibitor)-resistant cell lines, which are dependent on EGFR signaling for survival. Thus, these studies suggest that gallic acid can induce apoptosis in EGFR-dependent lung cancers that are dependent on EGFR for growth and survival via acceleration of EGFR turnover.

  3. EGFR and EGFRvIII undergo stress- and EGFR kinase inhibitor-induced mitochondrial translocalization: A potential mechanism of EGFR-driven antagonism of apoptosis

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    Ali-Osman Francis

    2011-03-01

    Full Text Available Abstract Background Epidermal growth factor receptor (EGFR plays an essential role in normal development, tumorigenesis and malignant biology of human cancers, and is known to undergo intracellular trafficking to subcellular organelles. Although several studies have shown that EGFR translocates into the mitochondria in cancer cells, it remains unclear whether mitochondrially localized EGFR has an impact on the cells and whether EGFRvIII, a constitutively activated variant of EGFR, undergoes mitochondrial transport similar to EGFR. Results We report that both receptors translocate into the mitochondria of human glioblastoma and breast cancer cells, following treatments with the apoptosis inducers, staurosporine and anisomycin, and with an EGFR kinase inhibitor. Using mutant EGFR/EGFRvIII receptors engineered to undergo enriched intracellular trafficking into the mitochondria, we showed that glioblastoma cells expressing the mitochondrially enriched EGFRvIII were more resistant to staurosporine- and anisomycin-induced growth suppression and apoptosis and were highly resistant to EGFR kinase inhibitor-mediated growth inhibition. Conclusions These findings indicate that apoptosis inducers and EGFR-targeted inhibitors enhance mitochondrial translocalization of both EGFR and EGFRvIII and that mitochondrial accumulation of these receptors contributes to tumor drug resistance. The findings also provide evidence for a potential link between the mitochondrial EGFR pathway and apoptosis.

  4. PGE2/EP3/SRC signaling induces EGFR nuclear translocation and growth through EGFR ligands release in lung adenocarcinoma cells

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    Bazzani, Lorenzo; Donnini, Sandra; Finetti, Federica; Christofori, Gerhard; Ziche, Marina

    2017-01-01

    Prostaglandin E2 (PGE2) interacts with tyrosine kinases receptor signaling in both tumor and stromal cells supporting tumor progression. Here we demonstrate that in non-small cell lung carcinoma (NSCLC) cells, A549 and GLC82, PGE2 promotes nuclear translocation of epidermal growth factor receptor (nEGFR), affects gene expression and induces cell growth. Indeed, cyclin D1, COX-2, iNOS and c-Myc mRNA levels are upregulated following PGE2 treatment. The nuclear localization sequence (NLS) of EGFR as well as its tyrosine kinase activity are required for the effect of PGE2 on nEGFR and downstream signaling activities. PGE2 binds its bona fide receptor EP3 which by activating SRC family kinases, induces ADAMs activation which, in turn, releases EGFR-ligands from the cell membrane and promotes nEGFR. Amphiregulin (AREG) and Epiregulin (EREG) appear to be involved in nEGFR promoted by the PGE2/EP3-SRC axis. Pharmacological inhibition or silencing of the PGE2/EP3/SRC-ADAMs signaling axis or EGFR ligands i.e. AREG and EREG expression abolishes nEGFR induced by PGE2. In conclusion, PGE2 induces NSCLC cell proliferation by EP3 receptor, SRC-ADAMs activation, EGFR ligands shedding and finally, phosphorylation and nEGFR. Since nuclear EGFR is a hallmark of cancer aggressiveness, our findings reveal a novel mechanism for the contribution of PGE2 to tumor progression. PMID:28415726

  5. Induced sensitivity to EGFR inhibitors is mediated by palmitoylated cysteine 1025 of EGFR and requires oncogenic Kras.

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    Kharbanda, Akriti; Runkle, Kristin; Wang, Wei; Witze, Eric S

    2017-11-04

    Currently, there are no effective therapeutic strategies targeting Kras driven cancers, and therefore, identifying new targeted therapies and overcoming drug resistance have become paramount for effective long-term cancer therapy. We have found that reducing expression of the palmitoyl transferase DHHC20 increases cell death induced by the EGFR inhibitor gefitinib in Kras and EGFR mutant cell lines, but not MCF7 cells harboring wildtype Kras. We show that the increased gefitinib sensitivity in cancer cells induced by DHHC20 inhibition is mediated directly through loss of palmitoylation on a previously identified cysteine residue in the C-terminal tail of EGFR. We utilized an EGFR point mutant in which the palmitoylated cysteine 1025 is mutated to alanine (EGFR(C1025A)), that results in receptor activation. Expression of the EGFR mutant alone in NIH3T3 cells does not increase sensitivity to gefitinib-induced cell death. However, when EGFR(C1025A) is expressed in cells expressing activated Kras(G12V), EGFR inhibitor induced cell death is increased. Surprisingly, lung cancer cells harboring the EGFR inhibitor resistant mutation, T790M, become sensitive to EGFR inhibitor treatment when DHHC20 is inhibited. Finally, the small molecule, 2-bromopalmitate, which has been shown to inhibit palmitoyl transferases, acts synergistically with gefitinib to induce cell death in the gefitinib resistant cell line NCI-H1975. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. 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.

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    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.

  7. Metastasis-associated PRL-3 induces EGFR activation and addiction in cancer cells.

    Science.gov (United States)

    Al-Aidaroos, Abdul Qader Omer; Yuen, Hiu Fung; Guo, Ke; Zhang, Shu Dong; Chung, Tae-Hoon; Chng, Wee Joo; Zeng, Qi

    2013-08-01

    Metastasis-associated phosphatase of regenerating liver-3 (PRL-3) has pleiotropic effects in driving cancer progression, yet the signaling mechanisms of PRL-3 are still not fully understood. Here, we provide evidence for PRL-3-induced hyperactivation of EGFR and its downstream signaling cascades in multiple human cancer cell lines. Mechanistically, PRL-3-induced activation of EGFR was attributed primarily to transcriptional downregulation of protein tyrosine phosphatase 1B (PTP1B), an inhibitory phosphatase for EGFR. Functionally, PRL-3-induced hyperactivation of EGFR correlated with increased cell growth, promigratory characteristics, and tumorigenicity. Moreover, PRL-3 induced cellular addiction to EGFR signaling, as evidenced by the pronounced reversion of these oncogenic attributes upon EGFR-specific inhibition. Of clinical significance, we verified elevated PRL-3 expression as a predictive marker for favorable therapeutic response in a heterogeneous colorectal cancer (CRC) patient cohort treated with the clinically approved anti-EGFR antibody cetuximab. The identification of PRL-3-driven EGFR hyperactivation and consequential addiction to EGFR signaling opens new avenues for inhibiting PRL-3-driven cancer progression. We propose that elevated PRL-3 expression is an important clinical predictive biomarker for favorable anti-EGFR cancer therapy.

  8. Graphene-induced apoptosis in lung epithelial cells through EGFR

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    Tsai, Shih-Ming; Bangalore, Preeti; Chen, Eric Y.; Lu, David; Chiu, Meng-Hsuen; Suh, Andrew; Gehring, Matthew; Cangco, John P.; Garcia, Santiago G.; Chin, Wei-Chun

    2017-07-01

    Expanding interest in nanotechnology applied to electronic and biomedical fields has led to fast-growing development of various nanomaterials. Graphene is a single-atom thick, two-dimensional sheet of hexagonally arranged carbon atoms with unique physical and chemical properties. Recently, graphene has been used in many studies on electronics, photonics, composite materials, energy generation and storage, sensors, and biomedicine. However, the current health risk assessment for graphene has been relatively limited and inconclusive. This study evaluated the toxicity effects of graphene on the airway epithelial cell line BEAS-2B, which represents the first barrier of the human body to interact with airborne graphene particles. Our result showed that graphene can induce the cellular Ca2+ by phospholipase C (PLC) associated pathway by activating epidermal growth factor receptor (EGFR). Subsequently, inositol 1,4,5-triphosphate (IP3) receptors activate the release of Ca2+ from the endoplasmic reticulum (ER) Ca2+ stores. Those Ca2+ signals further trigger the calcium-regulated apoptosis in the cell. Furthermore, the stimulation can cause EGFR upregulation, which have been demonstrated to associate with diseases such as lung cancer, chronic obstructive pulmonary disease (COPD), and cardiovascular diseases. This study highlights the additional health risk considering that it can function as a contributing factor for other respiratory diseases.

  9. Γ-Ionizing radiation activated EGFR-p38/ERK-STAT3/CREB-1-EMT pathway for promotion of the migration/invasion of lung cancer cell and its inhibition by podophyllotoxin acetate

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    Cho, Jeong Hyun; Um, Hong Duck; Park, Jong Kuk [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2016-05-15

    In this study, we sought to identify the intracellular machinery responsible for IR induced cancer invasion/migration. We report that IR activates the EGFR - p38/ERK - CREB-1/STAT3 pathway, which triggers EMT and increases invasion/migration of lung cancer. Moreover, we show that podophyllotoxin acetate (PA) inhibits IR-induced invasion/migration at least partly by blocking EGFR - p38/ERK - STAT3/ CREB-1signaling and thereby suppressing EMT. Our results revealed that IR increased the invasion/migration of A549 cells, and this effect was decreased by 10 nM PA treatment. PA also inhibited the expressions/activities of matrix metalloprotase (MMP) -2, MMP-9, and vimentin, suggesting that PA could block the IR-induced epithelial-mesenchymal transition (EMT). The IR induced increases in invasion/migration were associated with the activation of EGFR-AKT, and PA inhibited this effect. P38 and p44/42 ERK were also involved in IR induced invasion/migration, and combined treatments with PA plus inhibitors of each MAPK synergistically blocked this invasion/migration. In terms of transcription factors (TFs), IR-induced increases in cyclic AMP response element-binding protein-1 (CREB-1) and signal transducer and activator of transcription 3 (STAT3) increased invasion/migration and EMT. PA also inhibited these transcription factors and then blocked IR-induced invasion/migration.

  10. 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.

  11. 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.

  12. Differential Roles of Grb2 and AP-2 in p38 MAPK- and EGF-Induced EGFR Internalization

    DEFF Research Database (Denmark)

    Grandal, Michael V; Grøvdal, Lene M; Henriksen, Lasse;

    2012-01-01

    also can induce EGFR endocytosis. This endocytosis lacks many of the characteristics of ligand-induced EGFR endocytosis. We compared the two types of endocytosis with regard to the requirements for proteins in the internalization machinery. Both types of endocytosis require clathrin, but while...... epidermal growth factor (EGF)-induced EGFR internalization also required Grb2, p38 MAPK-induced internalization did not. Interestingly, AP-2 knock down blocked p38 MAPK-induced EGFR internalization, but only mildly affected EGF-induced internalization. In line with this, simultaneously mutating two AP-2...... interaction sites in EGFR affected p38 MAPK-induced internalization much more than EGF-induced EGFR internalization. Thus, it seems that EGFR in the two situations uses different sets of internalization mechanisms....

  13. 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.

  14. MUC1 contributes to BPDE-induced human bronchial epithelial cell transformation through facilitating EGFR activation.

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    Xiuling Xu

    Full Text Available Although it is well known that epidermal growth factor receptor (EGFR is involved in lung cancer progression, whether EGFR contributes to lung epithelial cell transformation is less clear. Mucin 1 (MUC1 in human and Muc1 in animals, a glycoprotein component of airway mucus, is overexpressed in lung tumors; however, its role and underlying mechanisms in early stage lung carcinogenesis is still elusive. This study provides strong evidence demonstrating that EGFR and MUC1 are involved in bronchial epithelial cell transformation. Knockdown of MUC1 expression significantly reduced transformation of immortalized human bronchial epithelial cells induced by benzo[a]pyrene diol epoxide (BPDE, the active form of the cigarette smoke (CS carcinogen benzo(apyrene (BaPs. BPDE exposure robustly activated a pathway consisting of EGFR, Akt and ERK, and blocking this pathway significantly increased BPDE-induced cell death and inhibited cell transformation. Suppression of MUC1 expression resulted in EGFR destabilization and inhibition of the BPDE-induced activation of Akt and ERK and increase of cytotoxicity. These results strongly suggest an important role for EGFR in BPDE-induced transformation, and substantiate that MUC1 is involved in lung cancer development, at least partly through mediating carcinogen-induced activation of the EGFR-mediated cell survival pathway that facilitates cell transformation.

  15. Management of egfr tki–induced dermatologic adverse events

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    Melosky, B.; Leighl, N.B.; Rothenstein, J.; Sangha, R.; Stewart, D.; Papp, K.

    2015-01-01

    Targeting the epidermal growth factor receptor (egfr) pathway has become standard practice for the treatment of advanced non-small-cell lung cancer. Compared with chemotherapy, egfr tyrosine kinase inhibitors (tkis) have been associated with improved efficacy in patients with an EGFR mutation. Together with the increase in efficacy comes an adverse event (ae) profile different from that of chemotherapy. That profile includes three of the most commonly occurring dermatologic aes: acneiform rash, stomatitis, and paronychia. Currently, no randomized clinical trials have evaluated the treatments for the dermatologic aes that patients experience when taking egfr tkis. Based on the expert opinion of the authors, some basic strategies have been developed to manage those key dermatologic aes. Those strategies have the potential to improve patient quality of life and compliance and to prevent inappropriate dose reductions. PMID:25908911

  16. Targeted Inhibition of EGFR and Glutaminase Induces Metabolic Crisis in EGFR Mutant Lung Cancer.

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    Momcilovic, Milica; Bailey, Sean T; Lee, Jason T; Fishbein, Michael C; Magyar, Clara; Braas, Daniel; Graeber, Thomas; Jackson, Nicholas J; Czernin, Johannes; Emberley, Ethan; Gross, Matthew; Janes, Julie; Mackinnon, Andy; Pan, Alison; Rodriguez, Mirna; Works, Melissa; Zhang, Winter; Parlati, Francesco; Demo, Susan; Garon, Edward; Krysan, Kostyantyn; Walser, Tonya C; Dubinett, Steven M; Sadeghi, Saman; Christofk, Heather R; Shackelford, David B

    2017-01-17

    Cancer cells exhibit increased use of nutrients, including glucose and glutamine, to support the bioenergetic and biosynthetic demands of proliferation. We tested the small-molecule inhibitor of glutaminase CB-839 in combination with erlotinib on epidermal growth factor receptor (EGFR) mutant non-small cell lung cancer (NSCLC) as a therapeutic strategy to simultaneously impair cancer glucose and glutamine utilization and thereby suppress tumor growth. Here, we show that CB-839 cooperates with erlotinib to drive energetic stress and activate the AMP-activated protein kinase (AMPK) pathway in EGFR (del19) lung tumors. Tumor cells undergo metabolic crisis and cell death, resulting in rapid tumor regression in vivo in mouse NSCLC xenografts. Consistently, positron emission tomography (PET) imaging with (18)F-fluoro-2-deoxyglucose ((18)F-FDG) and (11)C-glutamine ((11)C-Gln) of xenografts indicated reduced glucose and glutamine uptake in tumors following treatment with CB-839 + erlotinib. Therefore, PET imaging with (18)F-FDG and (11)C-Gln tracers can be used to non-invasively measure metabolic response to CB-839 and erlotinib combination therapy. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  17. Targeted Inhibition of EGFR and Glutaminase Induces Metabolic Crisis in EGFR Mutant Lung Cancer

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    Milica Momcilovic

    2017-01-01

    Full Text Available Cancer cells exhibit increased use of nutrients, including glucose and glutamine, to support the bioenergetic and biosynthetic demands of proliferation. We tested the small-molecule inhibitor of glutaminase CB-839 in combination with erlotinib on epidermal growth factor receptor (EGFR mutant non-small cell lung cancer (NSCLC as a therapeutic strategy to simultaneously impair cancer glucose and glutamine utilization and thereby suppress tumor growth. Here, we show that CB-839 cooperates with erlotinib to drive energetic stress and activate the AMP-activated protein kinase (AMPK pathway in EGFR (del19 lung tumors. Tumor cells undergo metabolic crisis and cell death, resulting in rapid tumor regression in vivo in mouse NSCLC xenografts. Consistently, positron emission tomography (PET imaging with 18F-fluoro-2-deoxyglucose (18F-FDG and 11C-glutamine (11C-Gln of xenografts indicated reduced glucose and glutamine uptake in tumors following treatment with CB-839 + erlotinib. Therefore, PET imaging with 18F-FDG and 11C-Gln tracers can be used to non-invasively measure metabolic response to CB-839 and erlotinib combination therapy.

  18. Acetobacter pasteurianus metabolic change induced by initial acetic acid to adapt to acetic acid fermentation conditions.

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    Zheng, Yu; Zhang, Renkuan; Yin, Haisong; Bai, Xiaolei; Chang, Yangang; Xia, Menglei; Wang, Min

    2017-08-02

    Initial acetic acid can improve the ethanol oxidation rate of acetic acid bacteria for acetic acid fermentation. In this work, Acetobacter pasteurianus was cultured in ethanol-free medium, and energy production was found to increase by 150% through glucose consumption induced by initial acetic acid. However, oxidation of ethanol, instead of glucose, became the main energy production pathway when upon culturing ethanol containing medium. Proteome assay was used to analyze the metabolism change induced by initial acetic acid, which provided insight into carbon metabolic and energy regulation of A. pasteurianus to adapt to acetic acid fermentation conditions. Results were further confirmed by quantitative real-time PCR. In summary, decreased intracellular ATP as a result of initial acetic acid inhibition improved the energy metabolism to produce more energy and thus adapt to the acetic acid fermentation conditions. A. pasteurianus upregulated the expression of enzymes related to TCA and ethanol oxidation to improve the energy metabolism pathway upon the addition of initial acetic acid. However, enzymes involved in the pentose phosphate pathway, the main pathway of glucose metabolism, were downregulated to induce a change in carbon metabolism. Additionally, the enhancement of alcohol dehydrogenase expression promoted ethanol oxidation and strengthened the acetification rate, thereby producing a strong proton motive force that was necessary for energy production and cell tolerance to acetic acid.

  19. Personalized prediction of EGFR mutation-induced drug resistance in lung cancer

    OpenAIRE

    Wang, Debby D.; Weiqiang Zhou; Hong Yan; Maria Wong; Victor Lee

    2013-01-01

    EGFR mutation-induced drug resistance has significantly impaired the potency of small molecule tyrosine kinase inhibitors in lung cancer treatment. Computational approaches can provide powerful and efficient techniques in the investigation of drug resistance. In our work, the EGFR mutation feature is characterized by the energy components of binding free energy (concerning the mutant-inhibitor complex), and we combine it with specific personal features for 168 clinical subjects to construct a...

  20. MALT1 is required for EGFR-induced NF-κB activation and contributes to EGFR-driven lung cancer progression.

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    Pan, D; Jiang, C; Ma, Z; Blonska, M; You, M J; Lin, X

    2016-02-18

    The transcription factor nuclear factor kappa B (NF-κB) has been implicated in having a crucial role in the tumorigenesis of many types of human cancers. Although epidermal growth factor receptor (EGFR) can directly activate NF-κB, the mechanism by which EGFR induces NF-κB activation and the role of NF-κB in EGFR-associated tumor progression is still not fully defined. Herein, we found that mucosa-associated lymphoid tissue 1 (MALT1) is involved in EGFR-induced NF-κB activation in cancer cells, and that MALT1 deficiency impaired EGFR-induced NF-κB activation. MALT1 mainly functions as a scaffold protein by recruiting E3 ligase TRAF6 to IKK complex to activate NF-κB in response to EGF stimulation. Functionally, MALT1 inhibition shows significant defects in EGFR-associated tumor malignancy, including cell migration, metastasis and anchorage-independent growth. To further access a physiological role of MALT1-dependent NF-κB activation in EGFR-driven tumor progression, we generated triple-transgenic mouse model (tetO-EGFR(L858R); CCSP-rtTA; Malt1(-/-)), in which mutant EGFR-driven lung cancer was developed in the absence of MALT1 expression. MALT1-deficient mice show significantly less lung tumor burden when compared with its heterozygous controls, suggesting that MALT1 is required for the progression of EGFR-induced lung cancer. Mechanistically, MALT1 deficiency abolished both NF-κB and STAT3 activation in vivo, which is a result of a defect of interleukin-6 production. In comparison, MALT1 deficiency does not affect tumor progression in a mouse model (LSL-K-ras(G12D); CCSP-Cre; Malt1(-/-)) in which lung cancer is induced by expressing a K-ras mutant. Thus, our study has provided the cellular and genetic evidence that suggests MALT1-dependent NF-κB activation is important in EGFR-associated solid-tumor progression.

  1. 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

  2. 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

    Abs is development of acquired resistance through mechanisms such as alterated 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....... 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......-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...

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

    Science.gov (United States)

    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

  4. EGFR tyrosine kinase inhibition radiosensitizes and induces apoptosis in malignant glioma and childhood ependymoma xenografts.

    Science.gov (United States)

    Geoerger, Birgit; Gaspar, Nathalie; Opolon, Paule; Morizet, Jackie; Devanz, Pauline; Lecluse, Yann; Valent, Alexander; Lacroix, Ludovic; Grill, Jacques; Vassal, Gilles

    2008-07-01

    Malignant gliomas and childhood ependymomas have a high rate of treatment failure. Epidermal growth factor receptor (EGFR) activation has been implicated in the tumorigenesis and radioresistance of many cancers, including brain tumors. Therefore, combining EGFR targeting with irradiation is a potentially attractive therapeutic option. We evaluated the tyrosine kinase inhibitor gefitinib for its antitumor activity and potential to radio-sensitize in vivo in two xenograft models: an EGFR amplified glioma and an EGFR expressing ependymoma, both derived from primary tumors. When administered at 100 mg/kg for 5 consecutive days, gefitinib-induced partial tumor regression in all treated EGFR amplified IGRG88 glioma xenografts. The addition of 1 Gy of irradiation prior to gefitinib administration resulted in 5 complete and 4 partial regressions for the 9 treated tumors as well as a significant tumor growth delay of 33 days for the combined treatment compared to 19 days for each therapy alone, suggesting additive antitumor activity. Tumor regression was associated with inhibition of AKT and MAPK pathways by gefitinib. In contrast, the ependymoma IGREP83 was sensitive to irradiation, but remained resistant to gefitinib. Combined treatment was associated with inhibition of radiation-induced MAPK phosphorylation and significant induction of apoptotic cell death though radiation-induced AKT phosphorylation was maintained. Depending on the scheduling of both therapies, a trend towards superior antitumor activity was observed with combined treatment. Thus, EGFR targeting through tyrosine kinase inhibition appears to be a promising new approach in the treatment of EGFR-driven glioma, particularly in combination with radiation therapy. (c) 2008 Wiley-Liss, Inc.

  5. Apigenin induces apoptosis and impairs head and neck carcinomas EGFR/ErbB2 signaling.

    Science.gov (United States)

    Masuelli, Laura; Marzocchella, Laura; Quaranta, Alessandro; Palumbo, Camilla; Pompa, Giorgio; Izzi, Valerio; Canini, Antonella; Modesti, Andrea; Galvano, Fabio; Bei, Roberto

    2011-01-01

    The development of head and neck squamous cell carcinomas (HNSCCs) is a multistep process progressing from precancerous lesions to highly malignant tumors. A critical role in HNSCCs development and progression is played by EGFR family members including EGFR and ErbB2. The aim of this study was to investigate the effect of apigenin, a low molecular weight flavonoid contained in fruits and vegetables, on growth and survival and on EGFR/ErbB2 signaling in cell lines derived from HNSCCs of the tongue (CAL-27, SCC-15) or pharynx (FaDu). Using sulforhodamine B assay, FACS analysis and activated caspase-3 detection by immunofluorescence, we here demonstrate that apigenin dose-dependently inhibits survival and induces apoptosis of HNSCC cells. Further, by performing western blotting with antibodies specific for phosphorylated EGFR, ErbB2, Erk1/2 and Akt we demonstrate that apigenin reduces ligand-induced phosphorylation of EGFR and ErbB2 and impairs their downstream signaling. On the whole, our results suggest that apigenin properties might be exploited for chemoprevention and/or therapy of head and neck carcinomas.

  6. Effects of EGFR Inhibitor on Helicobacter pylori Induced Gastric Epithelial Pathology in Vivo

    Directory of Open Access Journals (Sweden)

    Philip A. Robinson

    2013-10-01

    Full Text Available Helicobacter pylori transactivates the Epidermal Growth Factor Receptor (EGFR and predisposes to gastric cancer development in humans and animal models. To examine the importance of EGFR signalling to gastric pathology, this study investigated whether treatment of Mongolian gerbils with a selective EGFR tyrosine kinase inhibitor, EKB-569, altered gastric pathology in chronic H. pylori infection. Gerbils were infected with H. pylori and six weeks later received either EKB-569-supplemented, or control diet, for 32 weeks prior to sacrifice. EKB-569-treated H. pylori-infected gerbils had no difference in H. pylori colonisation or inflammation scores compared to infected animals on control diet, but showed significantly less corpus atrophy, mucous metaplasia and submucosal glandular herniations along with markedly reduced antral and corpus epithelial proliferation to apoptosis ratios. EKB-569-treated infected gerbils had significantly decreased abundance of Cox-2, Adam17 and Egfr gastric transcripts relative to infected animals on control diet. EGFR inhibition by EKB-569 therefore reduced the severity of pre-neoplastic gastric pathology in chronically H. pylori-infected gerbils. EKB-569 increased gastric epithelial apoptosis in H. pylori-infected gerbils which counteracted some of the consequences of increased gastric epithelial cell proliferation. Similar chemopreventative strategies may be useful in humans who are at high risk of developing H.pylori-induced gastric adenocarcinoma.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    DEFF Research Database (Denmark)

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

    2008-01-01

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

  10. Nickel may contribute to EGFR mutation and synergistically promotes tumor invasion in EGFR-mutated lung cancer via nickel-induced microRNA-21 expression.

    Science.gov (United States)

    Chiou, Yu-Hu; Liou, Saou-Hsing; Wong, Ruey-Hong; Chen, Chih-Yi; Lee, Huei

    2015-08-19

    We recently reported that nickel accumulation in lung tissues may be associated with an increased in p53 mutation risk via reduced DNA repair activity. Here, we hypothesized that nickel accumulation in lung tissues could contribute to EGFR mutations in never-smokers with lung cancer. We enrolled 76 never-smoking patients to evaluate nickel level in adjacent normal lung tissues by ICP-MS. The prevalence of EGFR mutations was significantly higher in the high-nickel subgroup than in the low-nickel subgroup. Intriguingly, the OR for the occurrence of EGFR mutations in female, adenocarcinoma, and female adenocarcinoma patients was higher than that of all patients. Mechanistically, SPRY2 and RECK expressions were decreased by nickel-induced miR-21 via activation of the EGFR/NF-κB signaling pathway, which promoted invasiveness in lung cancer cells, and particularly in the cells with EGFR L858R expression vector transfection. The patients' nickel levels were associated with miR-21 expression levels. Kaplan-Meier analysis revealed poorer overall survival (OS) and shorter relapse free survival (RFS) in the high-nickel subgroup than in low-nickel subgroup. The high-nickel/high-miR-21 subgroup had shorter OS and RFS periods when compared to the low-nickel/low-miR-21 subgroup. Our findings support previous epidemiological studies indicating that nickel exposure may not only contribute to cancer incidence but also promote tumor invasion in lung cancer.

  11. Quercetin induces growth arrest through activation of FOXO1 transcription factor in EGFR-overexpressing oral cancer cells.

    Science.gov (United States)

    Huang, Chun-Yin; Chan, Chien-Yi; Chou, I-Tai; Lien, Chia-Hsien; Hung, Hsiao-Chi; Lee, Ming-Fen

    2013-09-01

    The squamous cell carcinomas of the head and neck (SCCHNs) with aberrant epidermal growth factor receptor (EGFR) signaling are often associated with poor prognosis and low survival. Therefore, efficient inhibition of the EGFR signaling could intervene with the development of malignancy. Quercetin appears to be antitumorigenesis, but the underlying mechanism remains unclear in oral cancer. Fork-head box O (FOXO) transcription factors, Akt downstream effectors, are important regulators of cell growth. Here, we hypothesized that FOXO1 might be crucial in quercetin-induced growth inhibition in EGFR-overexpressing oral cancer. Quercetin treatment suppressed cell growth by inducing G2 arrest and apoptosis in EGFR-overexpressing HSC-3 and TW206 oral cancer cells. Quercetin inhibited EGFR/Akt activation with a concomitant induction of FOXO1 activation. FOXO1 knockdown attenuated quercetin-induced p21 and FasL expression and subsequent G2 arrest and apoptosis, respectively. Likewise, quercetin suppressed tumor growth in HSC-3 xenograft mice. Taken together, our data indicate that quercetin is an effective anticancer agent and that FOXO1 is crucial in quercetin-induced growth suppression in EGFR-overexpressing oral cancer. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. 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

    Directory of Open Access Journals (Sweden)

    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.

  13. Afatinib induces apoptosis in NSCLC without EGFR mutation through Elk-1-mediated suppression of CIP2A

    OpenAIRE

    Chao, Ting-Ting; Wang, Cheng-Yi; Chen, Yen-Lin; Lai, Chih-Cheng; Chang, Fang-Yu; Tsai, Yi-Ting; Chao, Chung-Hao H.; Shiau, Chung-Wai; Huang, Yuh-Chin T.; Yu, Chong-Jen; Chen, Kuen-Feng

    2014-01-01

    Afatinib has anti-tumor effect in non-small cell lung carcinoma (NSCLC) with epidermal growth factor receptor (EGFR) mutation. We found afatinib can also induce apoptosis in NSCLC cells without EGFR mutation through CIP2A pathway. Four NSCLC cell lines (H358 H441 H460 and A549) were treated with afatinib to determine their sensitivity to afatinib-induced cell death and apoptosis. The effects of CIP2A on afatinib-induced apoptosis were confirmed by overexpression and knockdown of CIP2A express...

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Relationship between EGFR Promoter Region Methylation and Secondary Resistance Which may be Induced by Gefitinib

    Directory of Open Access Journals (Sweden)

    Qilong WANG

    2015-04-01

    Full Text Available Background and objective Nowadays the secondary resistance of gefitinib in the treatment of lung adenocarcinoma is an outstanding problem. This research is to explore whether the gefitinib secondary resistance can be induced by gefitinib, to explore whether epidermal growth factor receptor (EGFR promotor methylation correlate with the gefitinib-resistance in PC9/GR cell lines and to find a new therapeutic target to overcome the gefitinib secondary resistance in lung adenocarcinoma. Methods In vitro cultivation of lung adenocarcinoma PC9 cell lines, apply gefitinib on lung adenocarcinoma PC9 cell lines, and improve drug concentration. MTT for test of gefitinib resistance index in PC9 cell and PC9/GR cell. Bisulfite sequencing polymerase chain reaction (BSP and Reverse transcription-polymerase chain reaction (RT-PCR for detection of EGFR promoter methylation status and mRNA expression. In vitro cultivation of lung adenocarcinoma PC9 cell lines, apply 1 μmol/L 5-Aza-dc on lung adenocarcinoma PC9/GR cell lines for 72 h. MTT method for test of gefitinib resistance index in PC9/GR cell. Results After improving the gefitinib concentration, MTT results showed that half maximal inhibitory concentration (IC50 of PC9 cell lines increase from (0.01±0.002 μmol/L to (3.95±0.23 μmol/L (P<0.05. BSP results showed that abnormal methylation sites compared the degree of methylation change: PC9: 59%; PC9/GR: 74% (P<0.05. RT-PCR results showed in PC9/GR cell lines, EGFR mRNA expression quantity increased (P<0.05. After applying 5-Aza-dc on PC9 cell lines, IC50 of PC9/GR decrease from (3.87±0.034 μmol/L to (2.55±0.14 μmol/L. Conclusion The PC9 cell line which is induced by improving gefitinib concentration will be resistant to gefitinib, and the gefitinib-resistant cell line PC9/GR could be built. EGFR gene promoter methylation may be one of the mechanisms for the secondary resistance to gefitinib.

  16. The role of epidermal growth factor receptor (EGFR) signaling in SARS coronavirus-induced pulmonary fibrosis.

    Science.gov (United States)

    Venkataraman, Thiagarajan; Frieman, Matthew B

    2017-07-01

    Many survivors of the 2003 outbreak of severe acute respiratory syndrome (SARS) developed residual pulmonary fibrosis with increased severity seen in older patients. Autopsies of patients that died from SARS also showed fibrosis to varying extents. Pulmonary fibrosis can be occasionally seen as a consequence to several respiratory viral infections but is much more common after a SARS coronavirus (SARS-CoV) infection. Given the threat of future outbreaks of severe coronavirus disease, including Middle East respiratory syndrome (MERS), it is important to understand the mechanisms responsible for pulmonary fibrosis, so as to support the development of therapeutic countermeasures and mitigate sequelae of infection. In this article, we summarize pulmonary fibrotic changes observed after a SARS-CoV infection, discuss the extent to which other respiratory viruses induce fibrosis, describe available animal models to study the development of SARS-CoV induced fibrosis and review evidence that pulmonary fibrosis is caused by a hyperactive host response to lung injury mediated by epidermal growth factor receptor (EGFR) signaling. We summarize work from our group and others indicating that inhibiting EGFR signaling may prevent an excessive fibrotic response to SARS-CoV and other respiratory viral infections and propose directions for future research. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Morusin Induces TRAIL Sensitization by Regulating EGFR and DR5 in Human Glioblastoma Cells.

    Science.gov (United States)

    Park, Dain; Ha, In Jin; Park, Sang-Yoon; Choi, Minji; Lim, Sung-Lyul; Kim, Sung-Hoon; Lee, Jun-Hee; Ahn, Kwang Seok; Yun, Miyong; Lee, Seok-Geun

    2016-02-26

    Glioblastoma is one of the most malignant primary tumors, and the prognosis for glioblastoma patients remains poor. Tumor-necrosis-factor-related apoptosis-inducing ligand (TRAIL) is considered a promising anticancer agent due to its remarkable ability to selectively kill tumor cells. However, since many cancers are resistant to TRAIL, strategies to overcome resistance are required for the successful use of TRAIL in the clinic. In the present study, the potential of morusin as a TRAIL sensitizer in human glioblastoma cells was evaluated. Treatment with TRAIL or morusin alone showed weak cytotoxicity in human glioblastoma cells. However, combination treatment of TRAIL with morusin synergistically decreased cell viability and increased apoptosis compared with single treatment. Morusin induced expression of death receptor 5 (DR5), but not DR4 or decoy receptors (DcR1 and DcR2). Furthermore, morusin significantly decreased anti-apoptotic molecules survivin and XIAP. In addition, morusin reduced expression of EGFR and PDFGR as well as phosphorylation of STAT3, possibly mediating down-regulation of survivin and XIAP. Together these results suggest that morusin enhances TRAIL sensitivity in human glioblastoma cells through regulating expression of DR5 and EGFR. Therefore, the combination treatment of TRAIL and morusin may be a new therapeutic strategy for malignant glioma patients.

  18. [Relationship between EGFR Promoter Region Methylation and Secondary Resistance Which may be Induced by Gefitinib].

    Science.gov (United States)

    Wang, Qilong; Li, Min; Hu, Chengping

    2015-04-01

    Nowadays the secondary resistance of gefitinib in the treatment of lung adenocarcinoma is an outstanding problem. This research is to explore whether the gefitinib secondary resistance can be induced by gefitinib, to explore whether epidermal growth factor receptor (EGFR) promotor methylation correlate with the gefitinib-resistance in PC9/GR cell lines and to find a new therapeutic target to overcome the gefitinib secondary resistance in lung adenocarcinoma. In vitro cultivation of lung adenocarcinoma PC9 cell lines, apply gefitinib on lung adenocarcinoma PC9 cell lines, and improve drug concentration. MTT for test of gefitinib resistance index in PC9 cell and PC9/GR cell. Bisulfite sequencing polymerase chain reaction (BSP) and Reverse transcription-polymerase chain reaction (RT-PCR) for detection of EGFR promoter methylation status and mRNA expression. In vitro cultivation of lung adenocarcinoma PC9 cell lines, apply 1 μmol/L 5-Aza-dc on lung adenocarcinoma PC9/GR cell lines for 72 h. MTT method for test of gefitinib resistance index in PC9/GR cell. After improving the gefitinib concentration, MTT results showed that half maximal inhibitory concentration (IC50) of PC9 cell lines increase from (0.01 ± 0.002) μmol/L to (3.95 ± 0.23) μmol/L (Pchange: PC9: 59%; PC9/GR: 74% (Presistant to gefitinib, and the gefitinib-resistant cell line PC9/GR could be built. EGFR gene promoter methylation may be one of the mechanisms for the secondary resistance to gefitinib.

  19. 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.

  20. Gomisin N enhances TNF-α-induced apoptosis via inhibition of the NF-κB and EGFR survival pathways.

    Science.gov (United States)

    Waiwut, Pornthip; Shin, Myoung-Sook; Inujima, Akiko; Zhou, Yue; Koizumi, Keiichi; Saiki, Ikuo; Sakurai, Hiroaki

    2011-04-01

    Tumor necrosis factor (TNF-α) is a pleiotropic cytokine that plays an important role in the control of cell proliferation, differentiation, and apoptosis. TNF-α-induced apoptosis is limited by TAK1-mediated activation of NF-κB (mainly p65-p50 hetrodimer) signaling pathway. We have recently reported that TAK1 regulates phosphorylation of EGFR at Ser-1046/7 through p38 MAPK, which cooperates with NF-κB in TNF-α-induced apoptosis. The present study investigated the effect of gomisins A and N, dibenzocyclooctadiene lignans isolated from the fruit of Schisandra chinensis, on TNF-α-induced apoptosis in HeLa cells. Gomisins A and N strongly promoted TNF-α-induced cleavage of caspase-3 and PARP-1, which are key markers of apoptosis. We found that gomisin N, but not gomisin A, inhibited the TNF-α-induced activation of NF-κB by suppressing the activation of IKKα. Gomisin N also inhibited p38-mediated phosphorylation of the EGFR at Ser-1046/7 and subsequent endocytosis of EGFR, another prosurvival pathway. The findings suggested that gomisin N enhanced TNF-α-induced apoptosis by suppressing of NF-κB and EGFR signaling pathways.

  1. Propofol enhances the cisplatin-induced apoptosis on cervical cancer cells via EGFR/JAK2/STAT3 pathway.

    Science.gov (United States)

    Li, Haoran; Lu, Yan; Pang, Yangyang; Li, Mengjiao; Cheng, Xi; Chen, Jiawei

    2017-02-01

    The main purpose of this study was to evaluate propofol and its combined effect with cisplatin on apoptosis of cervical cancer cells and molecular mechanisms of this phenomenon. The effects of propofol and cisplatin on cell viability and apoptosis were detected by cell counting kit-8 (CCK-8) assay, colony formation assay and flow cytometry assay. Besides, protein expression of EGFR/JAK2/STAT3 pathway was determined by western blot. STAT3 was over-expressed in cervical cancer cells by STAT3 cDNA. Expression of EGFR and STAT3 protein of human tissues was evaluated by immunohistochemistry (IHC) assay. In this study, we found that not only propofol alone could inhibit cervical cancer cells viability but also could increase the inhibitory effect of cisplatin on cervical cancer cells growth. Meanwhile, propofol sensitized cervical cancer cells to cisplatin-induced apoptosis but not affected normal cervical cells. In genetic level, propofol could enhance the anti-tumor effect of cisplatin through EGFR/JAK2/STAT3 pathway. Further studies indicated that overexpression of EGFR and STAT3 is related to poor prognoses in cervical cancer patients, which contributed to confirm the clinical role of combined application of propofol and cisplatin. Propofol enhances the cisplatin-induced cell apoptosis cervical cancer cells via EGFR/JAK2/STAT3 pathway and may be developed as a potential therapeutic agent to treat cervical cancer. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

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

    Science.gov (United States)

    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

  4. Cordycepin Induces Apoptosis and Inhibits Proliferation of Human Lung Cancer Cell Line H1975 via Inhibiting the Phosphorylation of EGFR.

    Science.gov (United States)

    Wang, Zheng; Wu, Xue; Liang, Yan-Ni; Wang, Li; Song, Zhong-Xing; Liu, Jian-Li; Tang, Zhi-Shu

    2016-09-27

    Cordycepin is an active component of the traditional Chinese medicine Cordyceps sinensis and Cordyceps militaris with notable anticancer activity. Though the prominent inhibitory activity was reported in different kinds of cancer cell lines, the concrete mechanisms remain elusive. It was reported that cordycepin could be converted into tri-phosphates in vivo to confuse a number of enzymes and interfere the normal cell function. For the inhibitory mechanism of EGFR inhibitors and the structure similarity of ATP and tri-phosphated cordycepin, human lung cancer cell line H1975 was employed to investigate the inhibitory effect of cordycepin. The results showed that cordycepin could inhibit cell proliferation and induce apoptosis in a dose-dependent manner. Cell cycle analysis revealed that H1975 cells could be arrested at the G₀/G₁ phase after cordycepin treatment. The expression levels of apoptosis-related protein Caspase-3 and Bcl-2 and phosphorylated expression levels of EGFR, AKT and ERK1/2 were all decreased compared with the control group stimulated with EGF. However, the protein expression levels of proapoptotic protein Bax and cleaved caspase-3 were increased. These results implied that cordycepin could inhibit cell proliferation and induce apoptosis via the EGFR signaling pathway. Our results indicated that there was potential to seek a novel EGFR inhibitor from cordycepin and its chemical derivatives.

  5. Cordycepin Induces Apoptosis and Inhibits Proliferation of Human Lung Cancer Cell Line H1975 via Inhibiting the Phosphorylation of EGFR

    Directory of Open Access Journals (Sweden)

    Zheng Wang

    2016-09-01

    Full Text Available Cordycepin is an active component of the traditional Chinese medicine Cordyceps sinensis and Cordyceps militaris with notable anticancer activity. Though the prominent inhibitory activity was reported in different kinds of cancer cell lines, the concrete mechanisms remain elusive. It was reported that cordycepin could be converted into tri-phosphates in vivo to confuse a number of enzymes and interfere the normal cell function. For the inhibitory mechanism of EGFR inhibitors and the structure similarity of ATP and tri-phosphated cordycepin, human lung cancer cell line H1975 was employed to investigate the inhibitory effect of cordycepin. The results showed that cordycepin could inhibit cell proliferation and induce apoptosis in a dose-dependent manner. Cell cycle analysis revealed that H1975 cells could be arrested at the G0/G1 phase after cordycepin treatment. The expression levels of apoptosis-related protein Caspase-3 and Bcl-2 and phosphorylated expression levels of EGFR, AKT and ERK1/2 were all decreased compared with the control group stimulated with EGF. However, the protein expression levels of proapoptotic protein Bax and cleaved caspase-3 were increased. These results implied that cordycepin could inhibit cell proliferation and induce apoptosis via the EGFR signaling pathway. Our results indicated that there was potential to seek a novel EGFR inhibitor from cordycepin and its chemical derivatives.

  6. 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

  7. Afatinib induces apoptosis in NSCLC without EGFR mutation through Elk-1-mediated suppression of CIP2A.

    Science.gov (United States)

    Chao, Ting-Ting; Wang, Cheng-Yi; Chen, Yen-Lin; Lai, Chih-Cheng; Chang, Fang-Yu; Tsai, Yi-Ting; Chao, Chung-Hao H; Shiau, Chung-Wai; Huang, Yuh-Chin T; Yu, Chong-Jen; Chen, Kuen-Feng

    2015-02-10

    Afatinib has anti-tumor effect in non-small cell lung carcinoma (NSCLC) with epidermal growth factor receptor (EGFR) mutation. We found afatinib can also induce apoptosis in NSCLC cells without EGFR mutation through CIP2A pathway. Four NSCLC cell lines (H358 H441 H460 and A549) were treated with afatinib to determine their sensitivity to afatinib-induced cell death and apoptosis. The effects of CIP2A on afatinib-induced apoptosis were confirmed by overexpression and knockdown of CIP2A expression in the sensitive and resistant cells, respectively. Reduction of Elk-1 binding to the CIP2A promoter and suppression of CIP2A transcription were analyzed. In vivo efficacy of afatinib against H358 and H460 xenografts tumors were also determined in nude mice. Afatinib induced significant cell death and apoptosis in H358 and H441 cells, but not in H460 or A549 cells. The apoptotic effect of afatinib in sensitive cells was associated with downregulation of CIP2A, promotion of PP2A activity and decrease in AKT phosphorylation. Afatinib suppressed CIP2A at the gene transcription level by reducing the promoter binding activity of Elk-1. Clinical samples showed that higher CIP2A expression predicted a poor prognosis and Elk-1 and CIP2A expressions were highly correlated. In conclusion, afatinib induces apoptosis in NSCLC without EGFR mutations through Elk-1/CIP2A/PP2A/AKT pathway.

  8. A novel role of Rho-kinase in the regulation of ligand-induced phosphorylated EGFR endocytosis via the early/late endocytic pathway in human fibrosarcoma cells.

    Science.gov (United States)

    Nishimura, Yukio; Bereczky, Biborka; Yoshioka, Kiyoko; Taniguchi, Shun'ichiro; Itoh, Kazuyuki

    2011-10-01

    The small GTPase RhoA and its downstream effectors, the Rho-associated kinase (Rho-kinase) family, are known to regulate cell morphology, motility, and tumor progression via the regulation of actin cytoskeleton rearrangement. In the present study, we evaluated the role of Rho-kinase in the intracellular endocytic trafficking of ligand-induced phosphorylated epidermal growth factor receptor (pEGFR). We investigated the time course of the internalization fate of EGF-induced pEGFR via the early/late endocytic pathway in human fibrosarcoma cell line HT1080 cells using Y-27632, a selective Rho-kinase inhibitor. We found, using confocal immunofluorescence microscopy and Western blot analysis, a large accumulation of pEGFR in the nuclei of HT1080 cells. In contrast, we observed decreased amounts of the pEGFR-positive staining in the nuclei along with an accumulation of cytosolic pEGFR staining when the cells were incubated for 15-30 min in the presence of Y-27632, implying that an aberrant endocytic trafficking mechanism of pEGFR occurs in HT1080 cells whereby pEGFR might be selectively translocated into the nucleus. Moreover, we demonstrated that after 15-min of stimulation with Texas Red-EGF, increasing numbers of pEGFR-positive staining that had colocalized with Texas Red-EGF-positive punctate staining were seen in the cytoplasm of HT1080 cells but after 30-min of stimulation, most of this staining had disappeared from the cytoplasm and a large accumulation of pEGFR-positive staining appeared in the nucleus. Thus, nuclear accumulation of pEGFR appears to occur in an EGF-dependent manner. In contrast, such nuclear pEGFR-positive staining was not seen in the Y-27632-treated cells. Furthermore, silencing of RhoA or Rho-kinases I/II by sequence specific siRNAs considerably inhibited the EGF-dependent nuclear accumulation of pEGFR. Collectively, these results provide the first evidence that Rho-kinase signaling pathway plays a suppressive role in the intracellular vesicle

  9. 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.

  10. Acetic Acid Causes Endoplasmic Reticulum Stress and Induces the Unfolded Protein Response in Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Nozomi Kawazoe

    2017-06-01

    Full Text Available Since acetic acid inhibits the growth and fermentation ability of Saccharomyces cerevisiae, it is one of the practical hindrances to the efficient production of bioethanol from a lignocellulosic biomass. Although extensive information is available on yeast response to acetic acid stress, the involvement of endoplasmic reticulum (ER and unfolded protein response (UPR has not been addressed. We herein demonstrated that acetic acid causes ER stress and induces the UPR. The accumulation of misfolded proteins in the ER and activation of Ire1p and Hac1p, an ER-stress sensor and ER stress-responsive transcription factor, respectively, were induced by a treatment with acetic acid stress (>0.2% v/v. Other monocarboxylic acids such as propionic acid and sorbic acid, but not lactic acid, also induced the UPR. Additionally, ire1Δ and hac1Δ cells were more sensitive to acetic acid than wild-type cells, indicating that activation of the Ire1p-Hac1p pathway is required for maximum tolerance to acetic acid. Furthermore, the combination of mild acetic acid stress (0.1% acetic acid and mild ethanol stress (5% ethanol induced the UPR, whereas neither mild ethanol stress nor mild acetic acid stress individually activated Ire1p, suggesting that ER stress is easily induced in yeast cells during the fermentation process of lignocellulosic hydrolysates. It was possible to avoid the induction of ER stress caused by acetic acid and the combined stress by adjusting extracellular pH.

  11. Acetic Acid Causes Endoplasmic Reticulum Stress and Induces the Unfolded Protein Response in Saccharomyces cerevisiae.

    Science.gov (United States)

    Kawazoe, Nozomi; Kimata, Yukio; Izawa, Shingo

    2017-01-01

    Since acetic acid inhibits the growth and fermentation ability of Saccharomyces cerevisiae, it is one of the practical hindrances to the efficient production of bioethanol from a lignocellulosic biomass. Although extensive information is available on yeast response to acetic acid stress, the involvement of endoplasmic reticulum (ER) and unfolded protein response (UPR) has not been addressed. We herein demonstrated that acetic acid causes ER stress and induces the UPR. The accumulation of misfolded proteins in the ER and activation of Ire1p and Hac1p, an ER-stress sensor and ER stress-responsive transcription factor, respectively, were induced by a treatment with acetic acid stress (>0.2% v/v). Other monocarboxylic acids such as propionic acid and sorbic acid, but not lactic acid, also induced the UPR. Additionally, ire1Δ and hac1Δ cells were more sensitive to acetic acid than wild-type cells, indicating that activation of the Ire1p-Hac1p pathway is required for maximum tolerance to acetic acid. Furthermore, the combination of mild acetic acid stress (0.1% acetic acid) and mild ethanol stress (5% ethanol) induced the UPR, whereas neither mild ethanol stress nor mild acetic acid stress individually activated Ire1p, suggesting that ER stress is easily induced in yeast cells during the fermentation process of lignocellulosic hydrolysates. It was possible to avoid the induction of ER stress caused by acetic acid and the combined stress by adjusting extracellular pH.

  12. 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.

  13. 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.

  14. 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.

  15. Helicobacter pylori Induces Serine Phosphorylation of EGFR via Novel TAK1-p38 Activation Pathway in an HB-EGF-Independent Manner.

    Science.gov (United States)

    Zaidi, Syed Faisal; Refaat, Alaa; Zhou, Yue; Sualeh Muhammad, Jibran; Shin, Myoung-Sook; Saiki, Ikuo; Sakurai, Hiroaki; Sugiyama, Toshiro

    2015-10-01

    The interaction of Helicobacter pylori with gastric epithelial cells can result in the activation of transcription factor NF-κB via TGF-β-activated kinase 1 (TAK1). In this study, we have demonstrated the role of H. pylori in the activation of EGFR via TAK1-mediated phosphorylation of p38. Gastric epithelial AGS or MKN-45 cells were co-cultured with wild-type or cagA(-) H. pylori strains. H. pylori was added to the cells, and the activation of EGFR, p65 (NF-κB) subunit, p38, ERK, and TAK1 was examined by Western blotting. Infected cells were pretreated with or without ligands, chemical inhibitors, anti-HB-EGF antibody, and siRNAs to evaluate the effects on phosphorylation of various EGFR residues. Fluorescence microscopy and flow cytometry were performed to detect the internalization of EGFR. Incubating cells with wild-type and CagA(-) H. pylori strains resulted in the rapid and transient phosphorylation of serine residues of EGFR. RNAi experiments using siRNA against TAK1 and p38 pathways blocked the phosphorylation of serine residue. Immunofluorescence and flow cytometry revealed that EGFR was internalized in H. pylori-infected cells after EGFR phosphorylation in a p38-dependent manner. In contrast, pretreatment with gefitinib and anti-HB-EGF antibody did not block both the phosphorylation and internalization of EGFR. Helicobacter pylori induces internalization of EGFR via novel TAK1-p38-serine activation pathway which is independent of HB-EGF. The interaction between TAK1 and EGFR in H. pylori-infected cells might open new dimensions in understanding H. pylori-associated gastric carcinogenesis. © 2015 John Wiley & Sons Ltd.

  16. 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.

  17. Vinyl acetate induces intracellular acidification in mouse oral buccal epithelial cells.

    Science.gov (United States)

    Nakamoto, Tetsuji; Wagner, Mark; Melvin, James E; Bogdanffy, Matthew S

    2005-08-14

    Vinyl acetate exposure in drinking water has been associated with tumor formation in the upper gastrointestinal tract of rats and mice. One potential mechanism for inducing carcinogenesis involves acidification of the intracellular environment due to the metabolism of vinyl acetate to acetic acid. Prolonged intracellular acidification is thought to produce cytotoxic and/or mitogenic responses that are the sentinel pharmacodynamic steps toward cancer. To determine whether exposure to vinyl acetate affects the intracellular pH of intact oral cavity tissue, isolated mouse oral buccal epithelium was loaded with the pH-sensitive dye BCECF, and then exposed to vinyl acetate concentrations ranging from 10 to 1000 microM for up to 4 min. Extracellular vinyl acetate exposure induced a progressive intracellular acidification that was reversible upon removal of the vinyl acetate. The rate of the acidification was concentration-dependent and increased exponentially within the concentration range tested. The magnitude of the vinyl acetate-induced acidification was inhibited by pretreatment with the carboxylesterase inhibitor bis(p-nitrophenyl)phosphate. These results are consistent with the hypothesis that vinyl acetate contributes to the generation and progression of oral cavity tumors via a process of intracellular acidification. Such a process has been proposed to have practical dose-response thresholds below which the intracellular environment can be maintained within homeostatic bounds and the contribution of exposure to carcinogenic risk is negligible.

  18. DC electric fields direct breast cancer cell migration, induce EGFR polarization, and increase the intracellular level of calcium ions.

    Science.gov (United States)

    Wu, Dan; Ma, Xiuli; Lin, Francis

    2013-01-01

    Migration of cancer cells leads to invasion of primary tumors to distant organs (i.e., metastasis). Growing number of studies have demonstrated the migration of various cancer cell types directed by applied direct current electric fields (dcEF), i.e., electrotaxis, and suggested its potential implications in metastasis. MDA-MB-231 cell, a human metastatic breast cancer cell line, has been shown to migrate toward the anode of dcEF. Further characterizations of MDA-MB-231 cell electrotaxis and investigation of its underlying signaling mechanisms will lead to a better understanding of electrically guided cancer cell migration and metastasis. Therefore, we quantitatively characterized MDA-MB-231 cell electrotaxis and a few associated signaling events. Using a microfluidic device that can create well-controlled dcEF, we showed the anode-directing migration of MDA-MB-231 cells. In addition, surface staining of epidermal growth factor receptor (EGFR) and confocal microscopy showed the dcEF-induced anodal EGFR polarization in MDA-MB-231 cells. Furthermore, we showed an increase of intracellular calcium ions in MDA-MB-231 cells upon dcEF stimulation. Altogether, our study provided quantitative measurements of electrotactic migration of MDA-MB-231 cells, and demonstrated the electric field-mediated EGFR and calcium signaling events, suggesting their involvement in breast cancer cell electrotaxis.

  19. Lead Acetate Induces Epithelium-Dependent Contraction of Airway Smooth Muscle

    OpenAIRE

    , Ramadan B. Sopi; , Kemajl Bislimi; , Fetah Halili; , Mentor Sopjani; , Burim Neziri; , Muharrem Jakupi

    2016-01-01

    The effect of lead acetate on tracheal smooth muscle (TSM) of dog pups was investigated in this study. In addition we studied the role of epithelium and involvement of nitric oxide (NO) in counteracting the effects of lead acetate on TSM as well as the modifying effects of lead acetate on contractile responses of TSM to acetylcholine (ACh) . Tracheal rings were excised and placed in in vitro organ baths. In vitro administration of lead acetate in increasing concentrations(10-7–10-3 M) induced...

  20. 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).

  1. Cell wall dynamics modulate acetic acid-induced apoptotic cell death of Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    António Rego

    2014-08-01

    Full Text Available Acetic acid triggers apoptotic cell death in Saccharomyces cerevisiae, similar to mammalian apoptosis. To uncover novel regulators of this process, we analyzed whether impairing MAPK signaling affected acetic acid-induced apoptosis and found the mating-pheromone response and, especially, the cell wall integrity pathways were the major mediators, especially the latter, which we characterized further. Screening downstream effectors of this pathway, namely targets of the transcription factor Rlm1p, highlighted decreased cell wall remodeling as particularly important for acetic acid resistance. Modulation of cell surface dynamics therefore emerges as a powerful strategy to increase acetic acid resistance, with potential application in industrial fermentations using yeast, and in biomedicine to exploit the higher sensitivity of colorectal carcinoma cells to apoptosis induced by acetate produced by intestinal propionibacteria.

  2. Cell wall dynamics modulate acetic acid-induced apoptotic cell death of Saccharomyces cerevisiae

    Science.gov (United States)

    Rego, António; Duarte, Ana M.; Azevedo, Flávio; Sousa, Maria J.; Côrte-Real, Manuela; Chaves, Susana R.

    2014-01-01

    Acetic acid triggers apoptotic cell death in Saccharomyces cerevisiae, similar to mammalian apoptosis. To uncover novel regulators of this process, we analyzed whether impairing MAPK signaling affected acetic acid-induced apoptosis and found the mating-pheromone response and, especially, the cell wall integrity pathways were the major mediators, especially the latter, which we characterized further. Screening downstream effectors of this pathway, namely targets of the transcription factor Rlm1p, highlighted decreased cell wall remodeling as particularly important for acetic acid resistance. Modulation of cell surface dynamics therefore emerges as a powerful strategy to increase acetic acid resistance, with potential application in industrial fermentations using yeast, and in biomedicine to exploit the higher sensitivity of colorectal carcinoma cells to apoptosis induced by acetate produced by intestinal propionibacteria. PMID:28357256

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. 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

  8. The ErbB4 CYT2 variant protects EGFR from ligand-induced degradation to enhance cancer cell motility

    NARCIS (Netherlands)

    Kiuchi, Tai; Ortiz-Zapater, Elena; Monypenny, James; Matthews, Daniel R; Nguyen, Lan K; Barbeau, Jody; Coban, Oana; Lawler, Katherine; Burford, Brian; Rolfe, Daniel J; de Rinaldis, Emanuele; Dafou, Dimitra; Simpson, Michael A; Woodman, Natalie; Pinder, Sarah; Gillett, Cheryl E; Devauges, Viviane; Poland, Simon P; Fruhwirth, Gilbert; Marra, Pierfrancesco; Boersma, Ykelien L; Plückthun, Andreas; Gullick, William J; Yarden, Yosef; Santis, George; Winn, Martyn; Kholodenko, Boris N; Martin-Fernandez, Marisa L; Parker, Peter; Tutt, Andrew; Ameer-Beg, Simon M; Ng, Tony

    2014-01-01

    The epidermal growth factor receptor (EGFR) is a member of the ErbB family that can promote the migration and proliferation of breast cancer cells. Therapies that target EGFR can promote the dimerization of EGFR with other ErbB receptors, which is associated with the development of drug resistance.

  9. 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.

  10. 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

    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 m...... 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...

  11. The dual targeting of EGFR and ErbB2 with the inhibitor Lapatinib corrects high glucose-induced apoptosis and vascular dysfunction by opposing multiple diabetes-induced signaling changes.

    Science.gov (United States)

    Benter, Ibrahim F; Sarkhou, Fatima; Al-Khaldi, Abeer T; Chandrasekhar, Bindu; Attur, Sreeja; Dhaunsi, Gursev S; Yousif, Mariam H M; Akhtar, Saghir

    2015-01-01

    The epidermal growth factor receptors, EGFR and EGFR2 (ErbB2), appear important mediators of diabetes-induced vascular dysfunction. We investigated whether targeted dual inhibition of EGFR and ErbB2 with Lapatinib would be effective in treating diabetes-induced vascular dysfunction in a rat model of type 1 diabetes. In streptozotocin-induced diabetes, chronic 4-week oral or acute, ex vivo, administration of Lapatinib prevented the development of vascular dysfunction as indicated by the attenuation of the hyper-reactivity of the diabetic mesenteric vascular bed (MVB) to norephinephrine without correcting hyperglycemia. Chronic in vivo or acute ex vivo Lapatinib treatment also significantly attenuated diabetes-induced increases in phosphorylation of EGFR, ErbB2, ERK1/2, AKT, ROCK2 and IkB-alpha as well as normalized the reduced levels of phosphorylated FOXO3A, and eNOS (Ser1177) in the diabetic MVB. Similar results were observed in vascular smooth muscle cells (VSMCs) cultured in high glucose (25 mM) treated with Lapatinib or small interfering RNA (siRNA) targeting the ErbB2 receptor. Lapatinib also prevented high glucose-induced apoptosis in VSMC. Thus, Lapatinib corrects hyperglycemia-induced apoptosis and vascular dysfunction with concomitant reversal of diabetes or high glucose-induced signaling changes in EGFR/ErbB2 and downstream signaling pathways implying that targeted dual inhibition of EGFR/ErbB2 might be an effective vasculoprotective treatment strategy in diabetic patients.

  12. Gefitinib analogue V1801 induces apoptosis of T790M EGFR-harboring lung cancer cells by up-regulation of the BH-3 only protein Noxa.

    Directory of Open Access Journals (Sweden)

    Bo Zhang

    Full Text Available Treatment of non-small cell lung cancer (NSCLC with drugs targeting the epidermal growth factor receptor (EGFR, e.g., gefitinib and erlotinib, will eventually fail because of the development of secondary mutations such as T790M in EGFR. Strategies to overcome this resistance are therefore an urgent need. In this study, we synthesized a dozen of novel gefitinib analogues and evaluated their effects on L858R/T790M-EGFR harboring NSCLC cells, and reported that one of these gefitinib mimetics, N-(2-bromo-5-(trifluoromethyl phenyl-6-methoxy-7-(3-(piperidin-1-ylpropoxyquinazolin-4-amine (hereafter, V1801, triggered apoptosis of the NSCLC cells and overcame gefitinib-resistance in mice inoculated with NCI-H1975 cells. Though V1801 only moderately inhibited EGFR kinase activity, it markedly induced the expression of the BH3-only protein Noxa, and Noxa silencing significantly reduced V1801-induced apoptosis of NCI-H1975 cells. It is showed that V1801 interfered with the expression of the transcription factor c-Myc and the extracellular signal regulated kinase (Erk pathway. V1801 in combination with proteasome inhibitor bortezomib exerted enhanced cytotoxicity in NCI-H1975 cells possibly due to potentiated induction of Noxa expression. These data indicate that gefinitib analogues with weak EGFR inhibitory activity may overcome drug-resistance via activation of BH-3 only pro-apoptotic proteins, and V1801 may have therapeutic potentials for NSCLC.

  13. 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.

  14. Antioxidant effects of Spirulina supplement against lead acetate-induced hepatic injury in rats

    Directory of Open Access Journals (Sweden)

    Walid Hamdy El-Tantawy

    2016-10-01

    Full Text Available Lead is a toxic metal that induces a wide range of behavioral, biochemical and physiological effects in humans. Oxidative damage has been proposed as a possible mechanism involved in lead toxicity. The current study was carried out to evaluate the antioxidant activities of Spirulina supplement against lead acetate -induced hepatic injury in rats. Five groups of rats were used in this study, Control, Lead acetate (100 mg/kg, Lead acetate (100 mg/kg + 0.5 g/kg Spirulina, Lead acetate (100 mg/kg + 1 g/kg Spirulina and Lead acetate + 25 mg/100 g Vitamin C (reference drug. All experimental groups received the oral treatment by stomach tube once daily for 4 weeks. Lead intoxication resulted in a significant increase in serum alanine transaminae (ALT, aspartate transaminae (AST activities, liver homogenate tumor necrosis factor-α (TNF-α, caspase-3, malondialdehyde (MDA, nitric oxide (NO levels and a significant decline of total serum protein, liver homogenate reduced glutathione (GSH level and superoxide dismutase (SOD activity. Both doses of Spirulina supplement as well as Vitamin C succeeded to improve the biochemical parameters of serum and liver and prevented the lead acetate-induced significant changes on plasma and antioxidant status of the liver. Both doses of Spirulina supplement had the same anti-apoptotic activity and high dose exhibited more antioxidant activity than that of low dose. In conclusion, the results of the present work revealed that Spirulina supplement had protective, antioxidant and anti-apoptotic effects on lead acetate-induced hepatic damage.

  15. Combined EGFR- and notch inhibition display additive inhibitory effect on glioblastoma cell viability and glioblastoma-induced endothelial cell sprouting in vitro

    DEFF Research Database (Denmark)

    Staberg, Mikkel; Michaelsen, Signe Regner; Stobbe Olsen, Marie-Louise;

    2016-01-01

    aimed at testing a combination treatment strategy using inhibitors targeting the notch and EGFR pathways. METHODS: For evaluation of cell viability a standard MTT assay was used. Western blotting (WB) and Q-RT-PCR were employed in order to assess the protein- and mRNA expression levels, respectively....... In order to determine angiogenic processes, we used an endothelial spheroid sprouting assay. For assessment of secreted VEGF from GBM cells we performed a VEGF-quantikine ELISA. RESULTS: GBM cells were confirmed to express EGFR and Notch and to have the capacity to induce endothelial cell sprouting....... Inhibition of EGFR and Notch signaling was achieved using either Iressa (gefitinib) or the gamma-secretase inhibitor DAPT. Our data showed that DAPT combined with Iressa treatment displayed increased inhibitory effect on cell viability and abrogated expression and activation of major pro-survival pathways...

  16. 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.

  17. 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.

  18. [Investigation of incidence and risk factors of subcutaneous granulomas induced by injection of leuprorelin acetate].

    Science.gov (United States)

    Fukui, Shinji; Nakai, Yasushi; Matsumoto, Yoshihiro; Kagebayashi, Yoriaki; Samma, Shoji

    2015-02-01

    We investigated the incidence of granuloma and its related factors in 180 patients with prostate cancer who showed subcutaneous granuloma formation during androgen deprivation therapy with subcutaneously administered leuprorelin acetate. A granuloma was defined as a persistent induration over 30 mm in diameter in the injected portion. Small indurations which often developed and disappeared after every injection were excluded. The survey was performed using a questionnaire after receiving written informed consent. Among the 180 patients with prostate cancer, 21 (11.7%) developed a granuloma at the injection portion, and subsequently the injection of leuprorelin acetate had to be discontinued. Eighteen of the 21 patients alternatively received goserelin acetate. Three patients had high-grade granulomas with ulcer and abscess formation, and were successfully treated with oral antibiotics. The average duration between the first injection of leuprorelin acetate and granuloma formation was 20.2 months (range : 4 to 62 months). There was no association between granuloma formation and patient backgrounds, such as allergic predisposition and past history. Twenty-one of the 180 prostatic cancer patients developed subcutaneous granuloma induced by the injection of leuprorelin acetate. The investigation showed an unexpectedly high incidence of granuloma formation. We must explain the risk of developing subcutaneous granuloma to the patients before introducing leuprorelin acetate.

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

    Science.gov (United States)

    Díaz Galindo, Carmen; Gómez-González, Beatriz; Salinas, Eva; Calderón-Vallejo, Denisse; Hernández-Jasso, Irma; Bautista, Eduardo; Quintanar, J Luis

    2015-01-01

    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 5th 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 1st 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. PMID:26807118

  20. Antinociceptive activity of lectins from Diocleinae seeds on acetic acid-induced writhing test in mice.

    Science.gov (United States)

    Holanda, Fernanda R; Coelho-de-Sousa, Andrelina N; Assreuy, Ana M S; Leal-Cardoso, José Henrique; Pires, Alana F; do Nascimento, Kyria S; Teixeira, Cícero S; Cavada, Benildo S; Santos, Cláudia F

    2009-01-01

    Diocleinae lectins administered per oral route in mice inhibited the abdominal constrictions induced by acetic acid. The percentage of the lectins antinociception varied from 61% for Canavalia grandiflora (ConGf) to 20% for Dioclea violacea. ConGf inhibited contortions at all doses tested but not in a dose-dependent manner, involving carbohydrate recognition.

  1. Activating PIK3CA Mutations Induce an Epidermal Growth Factor Receptor (EGFR)/Extracellular Signal-regulated Kinase (ERK) Paracrine Signaling Axis in Basal-like Breast Cancer.

    Science.gov (United States)

    Young, Christian D; Zimmerman, Lisa J; Hoshino, Daisuke; Formisano, Luigi; Hanker, Ariella B; Gatza, Michael L; Morrison, Meghan M; Moore, Preston D; Whitwell, Corbin A; Dave, Bhuvanesh; Stricker, Thomas; Bhola, Neil E; Silva, Grace O; Patel, Premal; Brantley-Sieders, Dana M; Levin, Maren; Horiates, Marina; Palma, Norma A; Wang, Kai; Stephens, Philip J; Perou, Charles M; Weaver, Alissa M; O'Shaughnessy, Joyce A; Chang, Jenny C; Park, Ben Ho; Liebler, Daniel C; Cook, Rebecca S; Arteaga, Carlos L

    2015-07-01

    Mutations in PIK3CA, the gene encoding the p110α catalytic subunit of phosphoinositide 3-kinase (PI3K) have been shown to transform human mammary epithelial cells (MECs). These mutations are present in all breast cancer subtypes, including basal-like breast cancer (BLBC). Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), we identified 72 protein expression changes in human basal-like MECs with knock-in E545K or H1047R PIK3CA mutations versus isogenic MECs with wild-type PIK3CA. Several of these were secreted proteins, cell surface receptors or ECM interacting molecules and were required for growth of PIK3CA mutant cells as well as adjacent cells with wild-type PIK3CA. The proteins identified by MS were enriched among human BLBC cell lines and pointed to a PI3K-dependent amphiregulin/EGFR/ERK signaling axis that is activated in BLBC. Proteins induced by PIK3CA mutations correlated with EGFR signaling and reduced relapse-free survival in BLBC. Treatment with EGFR inhibitors reduced growth of PIK3CA mutant BLBC cell lines and murine mammary tumors driven by a PIK3CA mutant transgene, all together suggesting that PIK3CA mutations promote tumor growth in part by inducing protein changes that activate EGFR. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. Activating PIK3CA Mutations Induce an Epidermal Growth Factor Receptor (EGFR)/Extracellular Signal-regulated Kinase (ERK) Paracrine Signaling Axis in Basal-like Breast Cancer*

    Science.gov (United States)

    Young, Christian D.; Zimmerman, Lisa J.; Hoshino, Daisuke; Formisano, Luigi; Hanker, Ariella B.; Gatza, Michael L.; Morrison, Meghan M.; Moore, Preston D.; Whitwell, Corbin A.; Dave, Bhuvanesh; Stricker, Thomas; Bhola, Neil E.; Silva, Grace O.; Patel, Premal; Brantley-Sieders, Dana M.; Levin, Maren; Horiates, Marina; Palma, Norma A.; Wang, Kai; Stephens, Philip J.; Perou, Charles M.; Weaver, Alissa M.; O'Shaughnessy, Joyce A.; Chang, Jenny C.; Park, Ben Ho; Liebler, Daniel C.; Cook, Rebecca S.; Arteaga, Carlos L.

    2015-01-01

    Mutations in PIK3CA, the gene encoding the p110α catalytic subunit of phosphoinositide 3-kinase (PI3K) have been shown to transform human mammary epithelial cells (MECs). These mutations are present in all breast cancer subtypes, including basal-like breast cancer (BLBC). Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), we identified 72 protein expression changes in human basal-like MECs with knock-in E545K or H1047R PIK3CA mutations versus isogenic MECs with wild-type PIK3CA. Several of these were secreted proteins, cell surface receptors or ECM interacting molecules and were required for growth of PIK3CA mutant cells as well as adjacent cells with wild-type PIK3CA. The proteins identified by MS were enriched among human BLBC cell lines and pointed to a PI3K-dependent amphiregulin/EGFR/ERK signaling axis that is activated in BLBC. Proteins induced by PIK3CA mutations correlated with EGFR signaling and reduced relapse-free survival in BLBC. Treatment with EGFR inhibitors reduced growth of PIK3CA mutant BLBC cell lines and murine mammary tumors driven by a PIK3CA mutant transgene, all together suggesting that PIK3CA mutations promote tumor growth in part by inducing protein changes that activate EGFR. PMID:25953087

  3. 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.

  4. Inappropriate platelet transfusion in a patient with ethylenediamine tetra- acetic acid (EDTA)--induced pseudothrombocytopenia.

    Science.gov (United States)

    Kakkar, Naveen; Garg, Geetu

    2006-01-01

    Automated platelet counts in the laboratory may be fictitiously low at times and require manual confirmation. Ethylenediaminetetra-acetic acid (EDTA) in few patients and healthy individuals can induce platelet aggregation, giving rise to a spuriously low automated platelet count. This phenomenon which occurs due to the presence of IgG antibodies, if unrecognized, can result in incorrect diagnosis and consequent inappropriate treatment. We present a patient who received inappropriate platelet transfusion as a result of EDTA induced spurious thrombocytopenia.

  5. 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.

  6. Lipid raft localization of EGFR alters the response of cancer cells to the EGFR tyrosine kinase inhibitor gefitinib.

    Science.gov (United States)

    Irwin, Mary E; Mueller, Kelly L; Bohin, Natacha; Ge, Yubin; Boerner, Julie L

    2011-09-01

    Epidermal growth factor receptor (EGFR) is overexpressed in many cancer types including ~30% of breast cancers. Several small molecule tyrosine kinase inhibitors (TKIs) targeting EGFR have shown clinical efficacy in lung and colon cancers, but no benefit has been noted in breast cancer. Thirteen EGFR expressing breast cancer cell lines were analyzed for response to EGFR TKIs. Seven were found to be EGFR TKI resistant; while shRNA knockdown of EGFR determined that four of these cell lines retained the requirement of EGFR protein expression for growth. Interestingly, EGFR localized to plasma membrane lipid rafts in all four of these EGFR TKI-resistant cell lines, as determined by biochemical raft isolation and immunofluorescence. When lipid rafts were depleted of cholesterol using lovastatin, all four cell lines were sensitized to EGFR TKIs. In fact, the effects of the cholesterol biosynthesis inhibitors and gefitinib were synergistic. While gefitinib effectively abrogated phosphorylation of Akt- and mitogen-activated protein kinase in an EGFR TKI-sensitive cell line, phosphorylation of Akt persisted in two EGFR TKI-resistant cell lines, however, this phosphorylation was abrogated by lovastatin treatment. Thus, we have shown that lipid raft localization of EGFR correlates with resistance to EGFR TKI-induced growth inhibition and pharmacological depletion of cholesterol from lipid rafts decreases this resistance in breast cancer cell lines. Furthermore, we have presented evidence to suggest that when EGFR localizes to lipid rafts, these rafts provide a platform to facilitate activation of Akt signaling in the absence of EGFR kinase activity.

  7. 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.

  8. Effects of L-cysteine on lead acetate induced neurotoxicity in albino mice.

    Science.gov (United States)

    Mahmoud, Y I; Sayed, S S

    2016-07-01

    Lead is a toxic heavy metal that adversely affects nervous tissues; it often occurs as an environmental pollutant. We investigated histological changes in the cerebral cortex, hippocampus and cerebellum of adult albino mice following exposure to lead acetate. We also studied the possible ameliorative effect of the chelating agent, L-cysteine, on lead-induced neurotoxicity. We divided albino mice into six groups: 1) vehicle-only control, 2) L-cysteine control, 3 and 4) treated for 7 days with 20 and 40 mg/kg lead acetate, respectively, and 5 and 6) treated for 7 days with 20 and 40 mg/kg lead acetate, respectively, followed by 50 mg/kg L-cysteine for 7 days. Lead acetate administration caused disorganization of cell layers, neuronal loss and degeneration, and neuropil vacuolization. Brain sections from lead-intoxicated mice treated with L-cysteine showed fewer pathological changes; the neuropil showed less vacuolization and the neurons appeared less damaged. L-cysteine at the dose we used only marginally alleviated lead-induced toxicity.

  9. 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.

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

    Directory of Open Access Journals (Sweden)

    Aleksandra Matuszyk

    2016-09-01

    Full Text Available 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.

  11. Inhibition of N-acetylglucosaminyltransferase V enhances the cetuximab-induced radiosensitivity of nasopharyngeal carcinoma cells likely through EGFR N-glycan alterations.

    Science.gov (United States)

    Huang, Xiaomin; Liu, Ting; Wang, Qiongyao; Zhu, Weiliang; Meng, Hui; Guo, Linlang; Wei, Ting; Zhang, Jian

    2017-05-23

    N-acetylglucosaminyltransferase V (GnT-V), an enzyme that catalyses the formation of the N-linked β-1-6 branching of oligosaccharides, is related to the radiosensitivity of nasopharyngeal carcinoma (NPC). Cetuximab (C225) is an epidermal growth factor receptor (EGFR) inhibitor used as a radiosensitizer in the treatment of NPC. In this study, we used GnT-V as a molecular target to further sensitize cetuximab-treated NPC cells to radiation. The results from two NPC cell lines (CNE1 and CNE2) revealed that the silencing of GnT-V enhanced cetuximab-induced radiosensitivity by decreasing the β-1-6 branching of oligosaccharides on the EGFR. GnT-V down-regulation combined with cetuximab decreased the survival fraction, healing rate and cell viability and increased the apoptosis rate. Concomitantly, the combination of cetuximab and irradiation did not change the EGFR mRNA and protein levels and decreased the β-1-6 branching on the EGFR. Subsequently, we further explored the signalling downstream of EGF, particularly the PI3K/Akt signalling pathway, and discovered that treatment consisting of GnT-V down-regulation, irradiation and cetuximab was negatively correlated with phospho-Akt and phspho-PI3K. Finally, an in vivo experiment with radiotherapy revealed that the combination of GnT-V down-regulation and cetuximab decelerated tumour growth. In summary, our study demonstrated that the combination of decreased GnT-V activity and cetuximab enhanced NPC radiosensitivity, and the possible mechanism underlying this effect might involve the N-linked β1-6 branching of the EGFR. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. 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.

  13. Kaempferol induces cell cycle arrest and apoptosis in renal cell carcinoma through EGFR/p38 signaling.

    Science.gov (United States)

    Song, Wenbin; Dang, Qiang; Xu, Defeng; Chen, Yule; Zhu, Guodong; Wu, Kaijie; Zeng, Jin; Long, Qingzhi; Wang, Xinyang; He, Dalin; Li, Lei

    2014-03-01

    Kaempferol has been shown to inhibit cell growth, induce apoptosis and cell cycle arrest in several tumors, but not in renal cell carcinoma (RCC). In the present study, we investigated the effects of kaempferol and the underlying mechanism(s) on the cell growth of RCC cells. MTT assay and colony formation assay were used to study cell growth, and flow cytometry was used to study apoptosis and cell cycles in different RCC cells treated with various doses of kaempferol. A significant inhibition on cell growth, induction of apoptosis and cell cycle arrest were observed in 786-O and 769-P cells after kaempferol treatment compared with the control group. Moreover, the results clearly showed that kaempferol causes a strong inhibition of the activation of the EGFR/p38 signaling pathways, upregulation of p21 expression and downregulation of cyclin B1 expression in human RCC cells, together with activation of PARP cleavages, induction of apoptotic death and inhibition of cell growth. Collectively, our results suggest that kaempferol may serve as a candidate for chemo-preventive or chemotherapeutic agents for RCC.

  14. Desmocollin 3 mediates follicle stimulating hormone-induced ovarian epithelial cancer cell proliferation by activating the EGFR/Akt signaling pathway.

    Science.gov (United States)

    Yang, Xiao; Wang, Jing; Li, Wen-Ping; Jin, Zhi-Jun; Liu, Xiao-Jun

    2015-01-01

    Follicle-stimulating hormone (FSH) is associated with the pathogenesis of ovarian cancer. We sought to explore whether desmocollin 3 (Dsc3) mediates FSH-induced ovarian epithelial cancer cell proliferation and whether the EGFR/Akt signaling pathway may be involved in this process. Dsc3 positivity in ovarian tissue specimens from 72 patients was assessed by immunohistochemistry. The positive expression rates of Dsc3 were similar in ovarian cancer tissues (24/31:77.4%) and borderline ovarian tumor tissues (18/22:81.8%) (P>0.05), but were significantly higher in these cancerous tissues than in benign ovarian cyst tissues (3/19:15.8%) (Pcancer cells (HO8910, Skov3ip, Skov and Hey cells, but not ES-2 and in borderline ovarian MCV152 tumor cells was higher than in the immortalized ovarian epithelial cell line, Moody. FSH up-regulated the expression of Dsc3 and EGFR in a dose- and time-dependent manner. Furthermore, a converse relationship between the expression of Dsc3, EFGR and PI3K/Akt signaling was elucidated using RNA interference and PI3K/Akt inhibitor in the absence and presence of FSH. A role for these proteins in FSH-induced cell proliferation was verified, highlighting their interdependence in mediating ovarian cancer cell function. These results suggest that Dsc3 can mediate FSH-induced ovarian cancer cell proliferation by activating the EGFR/Akt signaling pathway.

  15. Protective Effect of Ocimum basilicum Essential Oil Against Acetic Acid-Induced Colitis in Rats.

    Science.gov (United States)

    Rashidian, Amir; Roohi, Parnia; Mehrzadi, Saeed; Ghannadi, Ali Reza; Minaiyan, Mohsen

    2016-10-01

    Ocimum basilicum L has been traditionally used for the treatment of inflammatory bowel disease in Iran. This study investigates the ameliorative effect of Ocimum basilicum essential oil on an acetic acid-induced colitis model in rats. Ocimum basilicum essential oil with 2 doses (200 and 400 μL/kg) significantly ameliorated wet weight/length ratio of colonic tissue compared to the control group. Higher doses of essential oil (200 and 400 μL/kg) significantly reduced ulcer severity, ulcer area, and ulcer index. On the other hand, histological examination revealed the diminution of total colitis index as a marker for inflammatory cell infiltration in the colonic segments of rats treated with Ocimum basilicum essential oil (200 and 400 μL/kg). The increased level of myeloperoxidase was significantly decreased after the treatment with the essential oil (200 and 400 μL/kg). These results suggest that Ocimum basilicum exhibits protective effect against acetic acid-induced colitis.

  16. Mentha longifolia protects against acetic-acid induced colitis in rats.

    Science.gov (United States)

    Murad, Hussam A S; Abdallah, Hossam M; Ali, Soad S

    2016-08-22

    Mentha longifolia L (Wild Mint or Habak) (ML) is used in traditional medicine in treatment of many gastrointestinal disorders. This study aimed to evaluate potential protecting effect of ML and its major constituent, eucalyptol, against acetic acid-induced colitis in rats, a model of human inflammatory bowel disease (IBD). Rats were divided into ten groups (n=8) given orally for three days (mg/kg/day) the following: normal control, acetic acid-induced colitis (un-treated, positive control), vehicle (DMSO), sulfasalazine (500), ML extract (100, 500, 1000), and eucalyptol (100, 200, 400). After 24h-fasting, two ML of acetic acid (3%) was administered intrarectally. On the fifth day, serum and colonic biochemical markers, and histopathological changes were evaluated. Colitis significantly increased colonic myeloperoxidase activity and malonaldehyde level, and serum tumor necrosis factor-α, interleukin-6, and malonaldehyde levels while significantly decreased colonic and serum glutathione levels. All treatments (except ML 100, ML 1000, and eucalyptol 100) significantly reversed these changes where eucalyptol (400) showed the highest activity in a dose-dependent manner. The colitis-induced histopathological changes were mild in sulfasalazine and eucalyptol 400 groups, moderate in ML 500 and eucalyptol 200 groups, and severe in ML 100, ML 1000, and eucalyptol 100 groups nearly similar to colitis-untreated rats. ML (in moderate doses) and eucalyptol (dose-dependently) exerted protective effects against acetic acid-induced colitis in rats possibly through antioxidant and antiinflammatory properties suggesting a potential benefit in treatments of IBD. To our knowledge this is the first report addressing this point. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  17. Whacking a mole-cule: clinical activity and mechanisms of resistance to third generation EGFR inhibitors in EGFR mutated lung cancers with EGFR-T790M.

    Science.gov (United States)

    Costa, Daniel B; Kobayashi, Susumu S

    2015-12-01

    Epidermal growth factor receptor (EGFR) mutations, especially EGFR-exon 19 deletions and EGFR-L858R, are the most frequent actionable genomic events in lung adenocarcinomas. Tumors arise due to constitutively activated EGFR signaling and are susceptible to EGFR tyrosine kinase inhibitors (TKIs). First generation EGFR TKIs (gefitinib and erlotinib) and the second generation EGFR TKI afatinib are approved worldwide. Although targeted therapies against EGFR mutants induce dramatic initial responses, acquired resistance (through multiple biological mechanisms) to erlotinib, gefitinib and afatinib emerges within the first 1-2 years of continued monotherapy. EGFR-T790M accounts for more than half of acquired resistance to first or second generation EGFR TKIs by modifying ATP affinity and drug binding kinetics. Two new studies have shown that two covalent pyrimidine inhibitors-AZD9291 and rociletinib of EGFR-T790M (i.e., third generation EGFR TKIs) shown remarkable clinical activity in patients with acquired resistance to erlotinib, gefitinib and afatinib when the tumor carries EGFR-T790M in conjunction with an activating mutation. However, and regrettably, acquired resistance to these third generation EGFR TKIs has already been reported in preclinical models and clinical specimens; such as a tertiary mutation at EGFR-C797S that prevents covalent binding of EGFR TKIs. The experience with sequential EGFR TKI monotherapy highlights tumor heterogeneity and adaptability (i.e., relentless game of whack-a-mole played between TKIs and cancer), and will help shape future clinical development of novel combinatory approaches to manage EGFR mutated lung adenocarcinomas.

  18. Lanthanum acetate inhibits vascular calcification induced by vitamin D3 plus nicotine in rats.

    Science.gov (United States)

    Zhou, Ye-Bo; Jin, Shao-Ju; Cai, Yan; Teng, Xu; Chen, Li; Tang, Chao-Shu; Qi, Yong-Fen

    2009-08-01

    Lanthanum, a rare earth element, has been used to decrease serum phosphorus level in patients with chronic renal disease and hyperphosphatemia. We aimed to observe the effect and mechanism of two doses of lanthanum acetate (375 and 750 mg/kg/day) on vascular calcification induced by vitamin D3 plus nicotine treatment in rats for 4 weeks. As compared with control rats, rats with calcification showed widespread calcified nodules and irregular elastic fibers in calcified aorta on von Kossa calcium staining and increased aortic calcium and phosphorus contents, alkaline phosphatase (ALP) activity and bone-related protein expressions for osteopontin (OPN) and type III sodium dependent phosphate cotransporter Pit-1 (Pit-1). After treatment with either dose of lanthanum acetate, the calcified nodules and degree of irregular elastic fibers decreased in aortas. Lanthanum acetate at 750 mg/kg/day was more effective than 375 mg/kg/day in lessening vascular calcification by significantly reducing plasma phosphorus level, calcium x phosphorus product and ALP activity, by 30.3%, 28.6%, and 68.6%, respectively; reducing aortic phosphorus and calcium contents and ALP activity, by 48%, 53.1%, and 63.5% (all P nicotine alone. Lanthanum acetate could effectively inhibit the pathogenesis of vascular calcification.

  19. 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.

  20. The effect of sodium valproate on acetic acid-induced colitis in rats.

    Science.gov (United States)

    Najafi, Ali; Motaghi, Ehsan; Hosseini, Mohammad Javad; Ghasemi-Pirbaluti, Masoumeh

    2017-02-01

    Ulcerative colitis is a chronic recurrent disease with incomplete treatment options. The current article evaluated the effect of sodium valproate on acetic acid-induced ulcerative colitis in rats. Rats were randomly distributed into six groups including Sham group, colitis control group, sodium valproate treatment groups (50, 100 and 300 mg/kg, i.p.) and dexamethasone-treatment group. Dexamethasone was used as a reference drug. Colitis was induced by intracolonic instillation of 2 mL of 3% acetic acid solution. The efficacy of sodium valproate was evaluated by macroscopical and histopathological scoring systems, hematocrit measurement as well as biochemical analysis including myeloperoxidase (MPO) and pro-inflammatory cytokines assessment. Sodium valproate, particularly with doses of 100 and 300 mg/kg significantly improved weight loss, and macroscopic damage, reduced ulcer area, colon weight, microscopic colitis index and elevated hematocrit level. Biochemical experiments showed elevated levels of colonic MPO activity, interleukin 1β (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α) in colitis control group. Treatment with sodium valproate at the doses of 100 and 300 mg/Kg) decreased the MPO activity and colonic concentrations of IL-1β, IL-6 and TNF-α. The results provide evidence that sodium valproate has a protective effect in acetic acid-induced ulcerative colitis which might be due to its anti-inflammatory activities, and it may be useful in patients with ulcerative colitis.

  1. Neuroprotective potential ofIndigofera oblongifolia leaf methanolic extract against lead acetate-induced neurotoxicity

    Institute of Scientific and Technical Information of China (English)

    Saleh Al-Quraishy; Mohamed A Dkhil; Shaimaa R Ibrahim; Ahmed E Abdel Moneim

    2016-01-01

    Lead (Pb) is one of the most common environmental toxicants, exposure to which can cause signiifcant neurotoxicity and an associated decline in brain function. hTis study investigated the possible neuroprotec-tive role ofIndigofera oblongifolia leaf methanolic extract (IOLME) against lead-induced neurotoxicity. Rats were intraperitoneally injected with lead acetate, with or without IOLME (intragastric administration for 5 days), and the neuroprotective effect of IOLME was assessed by measuring the lead concentration, redox status (lipid peroxidation, nitric oxide and glutathione), enzymatic antioxidant activities (superoxide dis-mutase, catalase, glutathione peroxidase and reductase), PCR assays of apoptosis markers (Bax and Bcl-2) and histopathology of the brain. The increases in the lipid peroxidation, nitric oxide, and apoptosis, the decreases in the glutathione level and the activity of antioxidant enzymes, and the altered histology of the brain induced by lead acetate were mitigated in the brain of rats pre-treated with IOLME. These ifndings indicate that IOLME has beneifcial effects and it mitigates lead acetate-induced neurotoxicityviaits antiox-idant and anti-apoptotic activities.

  2. 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.

  3. 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

  4. 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

  5. Ability of the Met kinase inhibitor crizotinib and new generation EGFR inhibitors to overcome resistance to EGFR inhibitors.

    Directory of Open Access Journals (Sweden)

    Shigeki Nanjo

    Full Text Available PURPOSE: Although EGF receptor tyrosine kinase inhibitors (EGFR-TKI have shown dramatic effects against EGFR mutant lung cancer, patients ultimately develop resistance by multiple mechanisms. We therefore assessed the ability of combined treatment with the Met inhibitor crizotinib and new generation EGFR-TKIs to overcome resistance to first-generation EGFR-TKIs. EXPERIMENTAL DESIGN: Lung cancer cell lines made resistant to EGFR-TKIs by the gatekeeper EGFR-T790M mutation, Met amplification, and HGF overexpression and mice with tumors induced by these cells were treated with crizotinib and a new generation EGFR-TKI. RESULTS: The new generation EGFR-TKI inhibited the growth of lung cancer cells containing the gatekeeper EGFR-T790M mutation, but did not inhibit the growth of cells with Met amplification or HGF overexpression. In contrast, combined therapy with crizotinib plus afatinib or WZ4002 was effective against all three types of cells, inhibiting EGFR and Met phosphorylation and their downstream molecules. Crizotinib combined with afatinib or WZ4002 potently inhibited the growth of mouse tumors induced by these lung cancer cell lines. However, the combination of high dose crizotinib and afatinib, but not WZ4002, triggered severe adverse events. CONCLUSIONS: Our results suggest that the dual blockade of mutant EGFR and Met by crizotinib and a new generation EGFR-TKI may be promising for overcoming resistance to reversible EGFR-TKIs but careful assessment is warranted clinically.

  6. A plant flavonoid fisetin induces apoptosis in colon cancer cells by inhibition of COX2 and Wnt/EGFR/NF-κB-signaling pathways

    Science.gov (United States)

    Suh, Yewseok; Afaq, Farrukh; Johnson, Jeremy J.; Mukhtar, Hasan

    2009-01-01

    Overexpression of cyclooxygenase 2 (COX2) and uncontrolled wingless and Int (Wnt)-signaling pathway have long been suggested to play crucial roles in colorectal cancer. Studies show that selective COX2 inhibitors possess great potential as chemopreventive agents for colon cancer. Recent studies suggest that targeting COX2 and epidermal growth factor receptor (EGFR) may provide better therapeutic strategy than inhibiting either single target and that this may alleviate the problem of COX2 inhibitor-associated side effects. Therefore, there have been intensive efforts to develop novel dietary substances that target COX2 and EGFR activation. Fisetin is a naturally occurring flavonoid commonly found in various vegetables and fruits. We found that the treatment of COX2-overexpressing HT29 human colon cancer cells with fisetin (30–120 μM) resulted in induction of apoptosis, downregulation of COX2 protein expression without affecting COX1 and inhibited the secretion of prostaglandin E2. Treatment of cells with fisetin also inhibited Wnt-signaling activity through downregulation of β-catenin and T cell factor 4 and decreased the expression of target genes such as cyclin D1 and matrix metalloproteinase 7. Fisetin treatment of cells also inhibited the activation of EGFR and nuclear factor-kappa B (NF-κB). Finally, the formation of colonies in soft agar was suppressed by fisetin treatment. Taken together, we provide evidence that the plant flavonoid fisetin can induce apoptosis and suppress the growth of colon cancer cells by inhibition of COX2- and Wnt/EGFR/NF-κB-signaling pathways. We suggest that fisetin could be a useful agent for prevention and treatment of colon cancer. PMID:19037088

  7. 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.

  8. Protective effects of Spirulina maxima on hyperlipidemia and oxidative-stress induced by lead acetate in the liver and kidney

    Science.gov (United States)

    2010-01-01

    Background Oxidative damage has been proposed as a possible mechanism involved in lead toxicity, specially affecting the liver and kidney. Previous studies have shown the antioxidant effect of Spirulina maxima in several experimental models of oxidative stress. The current study was carried out to evaluate the antioxidant activity of Spirulina maxima against lead acetate-induced hyperlipidemia and oxidative damage in the liver and kidney of male rats. Control animals were fed on a standard diet and did not receive lead acetate (Control group). Experimental animals were fed on a standard laboratory diet with or without Spirulina maxima 5% in the standard laboratory diet and treated with three doses of lead acetate (25 mg each/weekly, intraperitoneal injection) (lead acetate with Spirulina, and lead acetate without Spirulina groups). Results The results showed that Spirulina maxima prevented the lead acetate-induced significant changes on plasma and liver lipid levels and on the antioxidant status of the liver and kidney. On the other hand, Spirulina maxima succeeded to improve the biochemical parameters of the liver and kidney towards the normal values of the Control group. Conclusions It was concluded that Spirulina maxima has protective effects on lead acetate-induced damage, and that the effects are associated with the antioxidant effect of Spirulina. PMID:20353607

  9. Successful EGFR-TKI rechallenge of leptomeningeal carcinomatosis after gefitinib-induced interstitial lung disease.

    Science.gov (United States)

    Nakamichi, Shinji; Kubota, Kaoru; Horinouchi, Hidehito; Kanda, Shintaro; Fujiwara, Yutaka; Nokihara, Hiroshi; Yamamoto, Noboru; Tamura, Tomohide

    2013-04-01

    We report the case of a 49-year-old non-smoking Japanese woman with backache and difficulty in walking. She was diagnosed as having advanced lung adenocarcinoma, and an epithelial growth factor receptor mutation (in-frame deletions in exon 19) was found. After radiation therapy of bone metastases with spinal cord compression and brain metastases, gefitinib was administered. On day 2, she developed acute interstitial lung disease. Gefitinib therapy was discontinued and treatment with high-dose steroid therapy improved the interstitial lung disease. Cisplatin plus pemetrexed was initiated as second-line chemotherapy, but she was hospitalized again for leptomeningeal carcinomatosis. Considering the poor prognosis of leptomeningeal carcinomatosis, we decided that erlotinib was our only choice of treatment. As a third-line treatment, erlotinib was administered after informing the patient about the high risk of interstitial lung disease. Neurological symptoms were improved within a week and interstitial lung disease did not recur. The patient has received erlotinib successfully for 18 months without the recurrence of leptomeningeal carcinomatosis. Erlotinib rechallenge after gefitinib-induced interstitial lung disease must be carefully chosen based on the balance of a patient's risk and benefit.

  10. 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.

    Science.gov (United States)

    Song, Xiulong; Wei, Zhengxi; Shaikh, Zahir A

    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 1-3μM 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.

  11. Protective effect of Etlingera elatior (torch ginger) extract on lead acetate--induced hepatotoxicity in rats.

    Science.gov (United States)

    Haleagrahara, Nagaraja; Jackie, Tan; Chakravarthi, Srikumar; Rao, Mallikarjuna; Kulur, Anupama

    2010-10-01

    Lead is known to disrupt the biological systems by altering the molecular interactions, cell signaling, and cellular function. Exposure to even low levels of lead may have potential hazardous effects on brain, liver, kidneys and testes. The efficacy of Etlingera elatior (torch ginger) to protect hepatotoxicity induced by lead acetate was evaluated experimentally in male Sprague - Dawley rats. Rats were exposed to lead acetate in drinking water (500 ppm) for 21 days and the effects of concurrent treatment with extract of E. elatior on hepatic lipid hydroperoxides (LPO), protein carbonyl content (PCC), total antioxidants (TA), superoxide dismutase (SOD), glutathione peroxidase (GPX) and glutathione S- Transferase (GST) levels and histopathological changes in liver were evaluated. There was a significant decrease in TA and other antioxidant enzymes (p induced changes in hepatic architecture. E. elatior has also reduced the blood lead levels (BLL). Thus, there has been extensive biochemical and structural alterations indicative of liver toxicity with exposure to lead and E. elatior treatment significantly reduced these oxidative damage. Our results suggest that E. elatior has a powerful antioxidant effect against lead-induced hepatotoxicity.

  12. PGE2-induced hypertrophy of cardiac myocytes involves EP4 receptor-dependent activation of p42/44 MAPK and EGFR transactivation.

    Science.gov (United States)

    Mendez, Mariela; LaPointe, Margot C

    2005-05-01

    Upon induction of cyclooxygenase-2 (COX-2), neonatal ventricular myocytes (VMs) mainly synthesize prostaglandin E2 (PGE2). The biological effects of PGE2 are mediated through four different G protein-coupled receptor (GPCR) subtypes (EP(1-4)). We have previously shown that PGE2 stimulates cAMP production and induces hypertrophy of VMs. Because the EP4 receptor is coupled to adenylate cyclase and increases in cAMP, we hypothesized that PGE2 induces hypertrophic growth of cardiac myocytes through a signaling cascade that involves EP4-cAMP and activation of protein kinase A (PKA). To test this, we used primary cultures of VMs and measured [3H]leucine incorporation into total protein. An EP4 antagonist was able to partially block PGE2 induction of protein synthesis and prevent PGE2-dependent increases in cell surface area and activity of the atrial natriuretic factor promoter, which are two other indicators of hypertrophic growth. Surprisingly, a PKA inhibitor had no effect. In other cell types, G protein-coupled receptor activation has been shown to transactivate the epidermal growth factor receptor (EGFR) and result in p42/44 mitogen-activated protein kinase (MAPK) activation and cell growth. Immunoprecipitation of myocyte lysates demonstrated that the EGFR was rapidly phosphorylated by PGE2 in VMs, and the EP4 antagonist blocked this. In addition, the selective EGFR inhibitor AG-1478 completely blocked PGE2-induced protein synthesis. We also found that PGE2 rapidly phosphorylated p42/44 MAPK, which was inhibited by the EP4 antagonist and by AG-1478. Finally, the p42/44 MAPK inhibitor PD-98053 (25 micromol/l) blocked PGE2-induced protein synthesis. Altogether, we believe these are the first data to suggest that PGE2 induces protein synthesis in cardiac myocytes in part via activation of the EP4 receptor and subsequent activation of p42/44 MAPK. Activation of p42/44 MAPK is independent of the common cAMP-PKA pathway and involves EP4-dependent transactivation of EGFR.

  13. 2,2'-diphenyl-3,3'-diindolylmethane: a potent compound induces apoptosis in breast cancer cells by inhibiting EGFR pathway.

    Directory of Open Access Journals (Sweden)

    Arijit Bhowmik

    Full Text Available Despite recent advances in medicine, 30-40% of patients with breast cancer show recurrence underscoring the need for improved effective therapy. In this study, by in vitro screening we have selected a novel synthetic indole derivative 2,2'-diphenyl-3,3'-diindolylmethane (DPDIM as a potential anti- breast cancer agent. DPDIM induces apoptosis both in vitro in breast cancer cells MCF7, MDA-MB 231 and MDA-MB 468 and in vivo in 7,12-dimethylbenz[α]anthracene (DMBA induced Sprague-Dawley (SD rat mammary tumor. Our in vitro studies show that DPDIM exerts apoptotic effect by negatively regulating the activity of EGFR and its downstream molecules like STAT3, AKT and ERK1/2 which are involved in the proliferation and survival of these cancer cells. In silico predictions also suggest that DPDIM may bind to EGFR at its ATP binding site. DPDIM furthermore inhibits EGF induced increased cell viability. We have also shown decreased expression of pro-survival factor Bcl-XL as well as increase in the level of pro-apoptotic proteins like Bax, Bad, Bim in DPDIM treated cells in vitro and in vivo. Our results further indicate that the DPDIM induced apoptosis is mediated through mitochondrial apoptotic pathway involving the caspase-cascade. To the best of our knowledge this is the first report of DPDIM for its anticancer activity. Altogether this report suggests that DPDIM could be an effective therapeutic agent for breast cancer.

  14. Involvement of yeast HSP90 isoforms in response to stress and cell death induced by acetic acid.

    Science.gov (United States)

    Silva, Alexandra; Sampaio-Marques, Belém; Fernandes, Angela; Carreto, Laura; Rodrigues, Fernando; Holcik, Martin; Santos, Manuel A S; Ludovico, Paula

    2013-01-01

    Acetic acid-induced apoptosis in yeast is accompanied by an impairment of the general protein synthesis machinery, yet paradoxically also by the up-regulation of the two isoforms of the heat shock protein 90 (HSP90) chaperone family, Hsc82p and Hsp82p. Herein, we show that impairment of cap-dependent translation initiation induced by acetic acid is caused by the phosphorylation and inactivation of eIF2α by Gcn2p kinase. A microarray analysis of polysome-associated mRNAs engaged in translation in acetic acid challenged cells further revealed that HSP90 mRNAs are over-represented in this polysome fraction suggesting preferential translation of HSP90 upon acetic acid treatment. The relevance of HSP90 isoform translation during programmed cell death (PCD) was unveiled using genetic and pharmacological abrogation of HSP90, which suggests opposing roles for HSP90 isoforms in cell survival and death. Hsc82p appears to promote survival and its deletion leads to necrotic cell death, while Hsp82p is a pro-death molecule involved in acetic acid-induced apoptosis. Therefore, HSP90 isoforms have distinct roles in the control of cell fate during PCD and their selective translation regulates cellular response to acetic acid stress.

  15. Involvement of Yeast HSP90 Isoforms in Response to Stress and Cell Death Induced by Acetic Acid

    Science.gov (United States)

    Silva, Alexandra; Sampaio-Marques, Belém; Fernandes, Ângela; Carreto, Laura; Rodrigues, Fernando; Holcik, Martin; Santos, Manuel A. S.; Ludovico, Paula

    2013-01-01

    Acetic acid-induced apoptosis in yeast is accompanied by an impairment of the general protein synthesis machinery, yet paradoxically also by the up-regulation of the two isoforms of the heat shock protein 90 (HSP90) chaperone family, Hsc82p and Hsp82p. Herein, we show that impairment of cap-dependent translation initiation induced by acetic acid is caused by the phosphorylation and inactivation of eIF2α by Gcn2p kinase. A microarray analysis of polysome-associated mRNAs engaged in translation in acetic acid challenged cells further revealed that HSP90 mRNAs are over-represented in this polysome fraction suggesting preferential translation of HSP90 upon acetic acid treatment. The relevance of HSP90 isoform translation during programmed cell death (PCD) was unveiled using genetic and pharmacological abrogation of HSP90, which suggests opposing roles for HSP90 isoforms in cell survival and death. Hsc82p appears to promote survival and its deletion leads to necrotic cell death, while Hsp82p is a pro-death molecule involved in acetic acid-induced apoptosis. Therefore, HSP90 isoforms have distinct roles in the control of cell fate during PCD and their selective translation regulates cellular response to acetic acid stress. PMID:23967187

  16. Lupeol induces apoptosis and inhibits invasion in gallbladder carcinoma GBC-SD cells by suppression of EGFR/MMP-9 signaling pathway.

    Science.gov (United States)

    Liu, Yan; Bi, Tingting; Shen, Genhai; Li, Zhimin; Wu, Guoliang; Wang, Zheng; Qian, Liqiang; Gao, Quangen

    2016-01-01

    The cytostatic drug from fruits and other plant derived products have acted as a chemotherapeutic agent used in treatment of a wide variety of cancers. Lupeol, a dietary triterpene, present in many fruits and medicinal plants, has been shown to possess many pharmacological properties including anti-cancer effect in both in vitro and in vivo assay systems. However, the cancer proliferative and invasive inhibitory effects and molecular mechanisms on gallbladder carcinoma GBC-SD cells have not been studied. In the present study, GBC-SD cells were treated by lupeol and subjected to methyl thiazolyl tetrazolium analysis, Hoechst 33342 staining, annexin V/propidium iodide double-staining, transwell chamber assay and Western blot analysis. In addition, GBC-SD xenograft tumors were established in male nude BALB/c mice, and lupeol was intravenously administered to evaluate the anti-cancer capacity in vivo. Our results showed that lupeol inhibited the proliferation, migration, invasion and induced apoptosis of GBC-SD cells in a dose-dependent manner in vitro. Furthermore, the expression of p-EGFR, p-AKT and MMP-9 levels were significantly down-regulated. These protein interactions may play a pivotal role in the regulation of apoptosis and invasion. More importantly, our in vivo studies showed that administration of lupeol decreased tumor growth in a dose-dependent manner. Immunohistochemistry analysis demonstrated the down-regulation of p-EGFR and MMP-9 in tumor tissues following lupeol treatment, consistent with the in vitro results. Taken together, our findings indicated that lupeol can induce apoptotic cell death and inhibit the migration as well as invasion of GBC-SD cells. The mechanism may be associated with the suppression of EGFR/MMP-9 signaling. These results might offer a therapeutic potential advantage for human gallbladder carcinoma chemoprevention or chemotherapy.

  17. Ubiquitin Ligase Cbl-b Is Involved in Icotinib (BPI-2009H-Induced Apoptosis and G1 Phase Arrest of EGFR Mutation-Positive Non-Small-Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Xiaodong Mu

    2013-01-01

    Full Text Available Epidermal growth factor receptor (EGFR is one of the most promising targets for non-small-cell lung cancer (NSCLC. Icotinib, a highly selective EGFR tyrosine kinase inhibitor (EGFR-TKI, has shown promising clinical efficacy and safety in patients with NSCLC. The exact molecular mechanism of icotinib remains unclear. In this study, we first investigated the antiproliferative effect of icotinib on NSCLC cells. Icotinib significantly inhibited proliferation of the EGFR-mutated lung cancer HCC827 cells. The IC50 values at 48 and 72 h were 0.67 and 0.07 μM, respectively. Flow cytometric analysis showed that icotinib caused the G1 phase arrest and increased the rate of apoptosis in HCC827 cells. The levels of cyclin D1 and cyclin A2 were decreased. The apoptotic process was associated with activation of caspase-3, -8, and poly(ADP-ribose polymerase (PARP. Further study revealed that icotinib inhibited phosphorylation of EGFR, Akt, and extracellular signal-regulated kinase. In addition, icotinib upregulated ubiquitin ligase Cbl-b expression. These observations suggest that icotinib-induced upregulation of Cbl-b is responsible, at least in part, for the antitumor effect of icotinib via the inhibition of phosphoinositide 3-kinase (PI3K/Akt and mitogen-activated protein kinase pathways in EGFR-mutated NSCLC cells.

  18. 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.

  19. Inhibition by medroxyprogesterone acetate of interleukin-1β-induced collagen degradation by corneal fibroblasts.

    Science.gov (United States)

    Zhou, Hongyan; Kimura, Kazuhiro; Orita, Tomoko; Nishida, Teruo; Sonoda, Koh-Hei

    2012-06-28

    To examine the effect of medroxyprogesterone 17-acetate (MPA) on interleukin-1β (IL-1β)-induced collagen degradation by corneal fibroblasts. Rabbit corneal fibroblasts were cultured in three-dimensional collagen gels with or without MPA. Collagen degradation was determined by measurement of hydroxyproline after acid hydrolysis. The expression or activity of matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) was evaluated by immunoblot analysis or gelatin zymography. The phosphorylation of mitogen-activated protein kinases (MAPKs) in corneal fibroblasts was examined by immunoblot analysis. Cell proliferation and viability were evaluated by measurement of bromodeoxyuridine incorporation and the release of lactate dehydrogenase, respectively. MPA inhibited IL-1β-induced collagen degradation by corneal fibroblasts in a concentration- and time-dependent manner. MMP expression and activation as well as TIMP expression in corneal fibroblasts exposed to IL-1β were also inhibited by MPA. MPA had no effect on cell proliferation or viability. MPA inhibited the IL-1β-induced phosphorylation of p38 MAPK without affecting that of the MAPKs ERK or JNK. IL-1β-induced MMP expression and activation as well as collagen degradation were also blocked by the p38 MAPK inhibitor SB203580. MPA inhibited MMP expression and thereby suppressed collagen degradation by corneal fibroblasts induced by IL-1β. Furthermore, inhibition of p38 MAPK phosphorylation by MPA may contribute to its inhibition of collagen degradation.

  20. Boswellic acid acetate induces differentiation and apoptosis in leukemia cell lines.

    Science.gov (United States)

    Jing, Y; Nakajo, S; Xia, L; Nakaya, K; Fang, Q; Waxman, S; Han, R

    1999-01-01

    Boswellic acid acetate (BC-4), a compound isolated from the herb Boswellia carterii Birdw., can induce differentiation and apoptosis of leukemia cells. Based on cell morphology and NBT reduction, BC-4 induced monocytic differentiation of myeloid leukemia HL-60, U937 and ML-1 cells at a dose under 12.5 microg/ml (24.2 microM). BC-4 was a potent inducer, with 90% of the cells showing morphologic changes and 80-90% of the cells showing NBT reduction. Specific and non-specific esterase were also increased by BC-4. Based on benzidine staining assay, BC-4 failed to induce erythroid leukemia DS-19 and K562 cells differentiation. In contrast to its selective differentiation effect, BC-4 strongly inhibited growth of all cell lines tested. The growth inhibition effect was dose- and time-dependent. In HL-60 cells, 20 microg/ml (38.8 microM) of BC-4 decreased viable cell number by 60% at 24 h, whereas at 3 days there was virtually no viable cells. Morphologic and DNA fragmentation analysis proved that BC-4 induced cell apoptosis. The dual apoptotic and differentiation effects of BC-4 suggest that it may be a powerful agent in the treatment of leukemia.

  1. Rabbit gastric ulcer models: comparison and evaluation of acetic acid-induced ulcer and mucosectomy-induced ulcer.

    Science.gov (United States)

    Maeng, Jin Hee; Lee, Eunhye; Lee, Don Haeng; Yang, Su-Geun

    2013-06-01

    In this study, we examined rabbit gastric ulcer models that can serve as more clinically relevant models. Two types of ulcer model were studied: acetic acid-induced ulcers (AAU) and mucosal resection-induced ulcers (MRU). For AAU, rabbit gastric mucosa was exposed by median laparotomy and treated with bottled acetic acid. MRU was examined as a model for endoscopic mucosal resection (EMR). Normal saline was injected into the submucosal layer and the swollen mucosa was resected with scissors. Endoscopic mucosal resection (EMR) is frequently performed for treatment of early gastric cancers. This procedure inevitably leads to ulcers and bleeding. Bleeding control is the major concern in endoscopic mucosectomy, and some endoscopic hemostatic agents are currently under clinical and preclinical studies. MRU was developed as a model for these induced ulcers and the evaluation of the healing process. The clinical relevancy of those models was compared with that of rat models. Progressive healing was observed for 7 days based on histology. Rabbit models demonstrate round, deep ulcers with clear margins and well-defined healing stages that were difficult to define in rat models.

  2. 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.

  3. [Effective prevention of indomethacin-induced gastroduodenal mucosal lesions with roxatidine acetate].

    Science.gov (United States)

    Dammann, H G; Wolf, N; Burkhardt, F

    1995-08-01

    In this randomized single-blind cross-over study the gastroduodenal damaging effect of indometacin 75 mg bid alone and in combination with roxatidine acetate (CAS 78628-28-1, Roxit) 75 mg nocte or 75 mg bid was evaluated in 12 healthy male volunteers. Prior to the start of the three therapeutic periods subjects underwent endoscopic examination to exclude gastroduodenal mucosa lesions. On days 7 and 14 of therapy 2 h after the application of the last indometacin dose subjects underwent endoscopy again. The 7- and 14-days administration of indometacin 75 mg bid, indometacin 75 mg bid plus roxatidine 75 mg nocte and indometacin 75 mg bid plus roxatidine 75 mg bid led to gastroduodenal mucosa lesion scores of 1.67 +/- 0.40 and 2.00 +/- 0.35, 1.33 +/- 0.28 and 1.50 +/- 0.29, 0.42 +/- 0.23 and 1.00 +/- 0.33 (mean +/- SEM), respectively. These differences were statistically significant when comparing indometacin 75 mg bid versus indometacin 75 mg bid plus roxatidine 75 mg bid (p roxatidine acetate represents an effective alternative in the prophylaxis of NSAID-induced gastroduodenal mucosa lesions.

  4. 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.

  5. Flavopiridol Synergizes with Sorafenib to Induce Cytotoxicity and Potentiate Antitumorigenic Activity in EGFR/HER-2 and Mutant RAS/RAF Breast Cancer Model Systems

    Directory of Open Access Journals (Sweden)

    Teddy S Nagaria

    2013-08-01

    Full Text Available Oncogenic receptor tyrosine kinase (RTK signaling through the Ras-Raf-Mek-Erk (Ras-MAPK pathway is implicated in a wide array of carcinomas, including those of the breast. The cyclin-dependent kinases (CDKs are implicated in regulating proliferative and survival signaling downstream of this pathway. Here, we show that CDK inhibitors exhibit an order of magnitude greater cytotoxic potency than a suite of inhibitors targeting RTK and Ras-MAPK signaling in cell lines representative of clinically recognized breast cancer (BC subtypes. Drug combination studies show that the pan-CDK inhibitor, flavopiridol (FPD, synergistically potentiated cytotoxicity induced by the Raf inhibitor, sorafenib (SFN. This synergy was most pronounced at sub-EC50 SFN concentrations in MDA-MB-231 (KRAS-G13D and BRAF-G464V mutations, MDA-MB-468 [epidermal growth factor receptor (EGFR overexpression], and SKBR3 [ErbB2/EGFR2 (HER-2 overexpression] cells but not in hormone-dependent MCF-7 and T47D cells. Potentiation of SFN cytotoxicity by FPD correlated with enhanced apoptosis, suppression of retinoblastoma (Rb signaling, and reduced Mcl-1 expression. SFN and FPD were also tested in an MDA-MB-231 mammary fat pad engraftment model of tumorigenesis. Mice treated with both drugs exhibited reduced primary tumor growth rates and metastatic tumor load in the lungs compared to treatment with either drug alone, and this correlated with greater reductions in Rb signaling and Mcl-1 expression in resected tumors. These findings support the development of CDK and Raf co-targeting strategies in EGFR/HER-2-overexpressing or RAS/RAF mutant BCs.

  6. 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.

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

    Directory of Open Access Journals (Sweden)

    Faiza Rao

    2016-08-01

    Full Text Available 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.

  8. 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.

  9. Contraction of rat thoracic aorta strips induced by phorbol 12-myristate 13-acetate

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, H.; Lederis, K.

    1987-02-01

    Phorbol 12-myristate 13-acetate (PMA) induced a slow and progressive increase in tension of rat thoracic aorta strips in the presence of extracellular CaS . Complete relaxation could not be obtained in CaS -free buffer containing 1 mM ethyleneglycol-bis(US -aminoethylether)-N,N'-tetraacetic acid (EGTA) and 10 X M PMA. In the absence of extracellular CaS , PMA (10 X M) induced a small but sustained contraction which was not altered by the addition of another 2 mM EGTA and 3 x 10 V M verapamil. Papaverine (10 U M) relaxed the PMA-induced contraction to the base line, but phentolamine (10 V M), cyproheptadine (10 V M), atropine (10 V M) and tetrodotoxine (10 W M) did not change the contraction. CaS -depleted muscle strips, prepared by four repeated applications of 10 X M norepinephrine in CaS -free buffer, were contracted by 10 X M PMA, but at a lower maximum tension than nontreated strips. The action of PMA on rat aorta strips in CaS -free buffer did not require the presence of the adventitial layer or endothelial cells. These results suggest that PMA may induce activation of protein kinase C and smooth muscle contraction in the absence of extracellular CaS , without an increase in myoplasmic CaS .

  10. 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.

  11. ParaHydrogen Induced Polarization of 13C carboxylate resonance in acetate and pyruvate.

    Science.gov (United States)

    Reineri, Francesca; Boi, Tommaso; Aime, Silvio

    2015-01-05

    The advent of nuclear spins hyperpolarization techniques represents a breakthrough in the field of medical diagnoses by magnetic resonance imaging. Dynamic nuclear polarization (DNP) is the most widely used method, and hyperpolarized metabolites such as [1-(13)C]-pyruvate are shown to report on status of tumours. Parahydrogen-induced polarization (PHIP) is a chemistry-based technique, easier to handle and much less expensive in respect to DNP, with significantly shorter polarization times. Its main limitation is the availability of unsaturated precursors for the target substrates; for instance, acetate and pyruvate cannot be obtained by direct incorporation of the parahydrogen molecule. Herein we report a method that allows us to achieve hyperpolarization in this kind of molecule by means of a tailored precursor containing a hydrogenable functionality that, after polarization transfer to the target (13)C moiety, is cleaved to obtain the metabolite of interest. The reported procedure can be extended to a number of other biologically relevant substrates.

  12. Computational modeling of allosteric communication reveals organizing principles of mutation-induced signaling in ABL and EGFR kinases.

    Directory of Open Access Journals (Sweden)

    Anshuman Dixit

    2011-10-01

    Full Text Available The emerging structural information about allosteric kinase complexes and the growing number of allosteric inhibitors call for a systematic strategy to delineate and classify mechanisms of allosteric regulation and long-range communication that control kinase activity. In this work, we have investigated mechanistic aspects of long-range communications in ABL and EGFR kinases based on the results of multiscale simulations of regulatory complexes and computational modeling of signal propagation in proteins. These approaches have been systematically employed to elucidate organizing molecular principles of allosteric signaling in the ABL and EGFR multi-domain regulatory complexes and analyze allosteric signatures of the gate-keeper cancer mutations. We have presented evidence that mechanisms of allosteric activation may have universally evolved in the ABL and EGFR regulatory complexes as a product of a functional cross-talk between the organizing αF-helix and conformationally adaptive αI-helix and αC-helix. These structural elements form a dynamic network of efficiently communicated clusters that may control the long-range interdomain coupling and allosteric activation. The results of this study have unveiled a unifying effect of the gate-keeper cancer mutations as catalysts of kinase activation, leading to the enhanced long-range communication among allosterically coupled segments and stabilization of the active kinase form. The results of this study can reconcile recent experimental studies of allosteric inhibition and long-range cooperativity between binding sites in protein kinases. The presented study offers a novel molecular insight into mechanistic aspects of allosteric kinase signaling and provides a quantitative picture of activation mechanisms in protein kinases at the atomic level.

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

    Science.gov (United States)

    Kuroda, Shinji; Tam, Justina; Roth, Jack A; Sokolov, Konstantin; Ramesh, Rajagopal

    2014-01-01

    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 G2/M checkpoint by inhibiting BRCA1, Chk1, and phospho-Cdc2/CDK1 protein expression. In vivo therapy studies showed 225-NP treatment reduced EGFR phosphorylation, increased γH2AX foci, and induced tumor cell apoptosis, resulting in suppression of tumor growth. Conclusion The 225-NP treatment induces DNA damage and abrogates G2/M phase of the cell cycle, leading to cellular apoptosis and suppression of lung tumor growth

  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. Sonic Hedgehog modulates EGFR dependent proliferation of neural stem cells during late mouse embryogenesis through EGFR transactivation

    Science.gov (United States)

    Reinchisi, Gisela; Parada, Margarita; Lois, Pablo; Oyanadel, Claudia; Shaughnessy, Ronan; Gonzalez, Alfonso; Palma, Verónica

    2013-01-01

    Sonic Hedgehog (Shh/GLI) and EGFR signaling pathways modulate Neural Stem Cell (NSC) proliferation. How these signals cooperate is therefore critical for understanding normal brain development and function. Here we report a novel acute effect of Shh signaling on EGFR function. We show that during late neocortex development, Shh mediates the activation of the ERK1/2 signaling pathway in Radial Glial cells (RGC) through EGFR transactivation. This process is dependent on metalloprotease activity and accounts for almost 50% of the EGFR-dependent mitogenic response of late NSCs. Furthermore, in HeLa cancer cells, a well-known model for studying the EGFR receptor function, Shh also induces cell proliferation involving EGFR activation, as reflected by EGFR internalization and ERK1/2 phosphorylation. These findings may have important implications for understanding the mechanisms that regulate NSC proliferation during neurogenesis and may lead to novel approaches to the treatment of tumors. PMID:24133411

  16. 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...

  17. 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.

  18. 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

  19. Brigatinib combined with anti-EGFR antibody overcomes osimertinib resistance in EGFR-mutated non-small-cell lung cancer

    Science.gov (United States)

    Uchibori, Ken; Inase, Naohiko; Araki, Mitsugu; Kamada, Mayumi; Sato, Shigeo; Okuno, Yasushi; Fujita, Naoya; Katayama, Ryohei

    2017-03-01

    Osimertinib has been demonstrated to overcome the epidermal growth factor receptor (EGFR)-T790M, the most relevant acquired resistance to first-generation EGFR-tyrosine kinase inhibitors (EGFR-TKIs). However, the C797S mutation, which impairs the covalent binding between the cysteine residue at position 797 of EGFR and osimertinib, induces resistance to osimertinib. Currently, there are no effective therapeutic strategies to overcome the C797S/T790M/activating-mutation (triple-mutation)-mediated EGFR-TKI resistance. In the present study, we identify brigatinib to be effective against triple-mutation-harbouring cells in vitro and in vivo. Our original computational simulation demonstrates that brigatinib fits into the ATP-binding pocket of triple-mutant EGFR. The structure-activity relationship analysis reveals the key component in brigatinib to inhibit the triple-mutant EGFR. The efficacy of brigatinib is enhanced markedly by combination with anti-EGFR antibody because of the decrease of surface and total EGFR expression. Thus, the combination therapy of brigatinib with anti-EGFR antibody is a powerful candidate to overcome triple-mutant EGFR.

  20. miR-2861 acts as a tumor suppressor via targeting EGFR/AKT2/CCND1 pathway in cervical cancer induced by human papillomavirus virus 16 E6.

    Science.gov (United States)

    Xu, Junfen; Wan, Xiaoyun; Chen, Xiaojing; Fang, Yifeng; Cheng, Xiaodong; Xie, Xing; Lu, Weiguo

    2016-07-01

    Persistent infection with oncogenic human papillomavirus viruses (HPVs) is a casual factor for cervical cancer and its precursors, and the abnormal constitutive expression of viral oncoprotein E6 is a key event during the malignant transformation. Here, we performed miRNA microarray to identify changes of miRNAs following ectopic HPV16 E6 overexpression in HEK293T cells and found miR-2861 was greatly decreased in both HEK293T and HaCaT cells expressing HPV16 E6 compared to vector control. Further, we demonstrated a biological link among HPV16 E6, miR-2861, EGFR, AKT2, and CCND1 in cervical cancer cells. We showed that miR-2861 was downregulated in cervical cancer tissues and negatively correlated with advanced tumor stage and lymph node metastasis. Overexpression of miR-2861 suppressed cervical cancer cell proliferation and invasion and enhanced apoptosis. Subsequent investigation revealed that EGFR, AKT2, and CCND1 were all the direct targets of miR-2861. Importantly, silencing EGFR, AKT2, and/or CCND1 recapitulated the cellular effects seen upon miR-2861 overexpression. Restoration of EGFR, AKT2, and/or CCND1 counteracted the effects of miR-2861 expression. Thus, we identified a new pathway employing miR-2861, EGFR, AKT2, and CCND1 that may mediate HPV16 E6 induced initiation and progression of cervical cancer.

  1. The effect of intracerebroventricular injection of histamine in visceral nociception induced by acetic acid in rats

    Directory of Open Access Journals (Sweden)

    Zanboori Ali

    2010-01-01

    Full Text Available Objective : This study was designed to investigate the role of brain histamine and H1 and H2 receptors in mediating the central perception of visceral pain in rats. Materials and Methods : In conscious rats implanted with a lateral brain ventricle cannula, the effect of intracerebroventricular (i.c.v. injection of histamine (2.5, 10, and 40 μg, and chlorpheniramine and ranitidine at the same doses of 5, 20, and 80 μg were investigated on visceral pain. Visceral nociception induced by intraperitoneal (i.p. injection of acetic acid (1 mL, 1%, and the number of complete abdominal wall muscle contractions accompanied with stretching of hind limbs (writhes were counted for 1 h. Results : Histamine at doses of 10 and 40 μg and chlorpheniramine and ranitidine at the same doses of 20 and 80 μg, significantly decreased the numbers of writhes (P < 0.05. Pretreatment with chlorpheniramine and ranitidine at the same dose of 80 μg, significantly prevented histamine (40 μg-induced antinociception (P < 0.05. Conclusion : The results of this study suggest that brain histamine may be involved in modulation of visceral antinociception through both central H 1 and H 2 receptors.

  2. Nadroparin sodium activates Nrf2/HO-1 pathway in acetic acid-induced colitis in rats.

    Science.gov (United States)

    Yalniz, Mehmet; Demirel, Ulvi; Orhan, Cemal; Bahcecioglu, Ibrahim Halil; Ozercan, Ibrahim Hanefi; Aygun, Cem; Tuzcu, Mehmet; Sahin, Kazim

    2012-06-01

    Effects of nadroparin sodium, a low molecular weight heparin, in colitis was investigated by analyzing proteins implicated in nuclear factor E2-related factor-2/heme oxygenase-1 (Nrf2/HO-1) and nuclear factor kappa B (NF-κB) pathways. Twenty-eight rats were used. Colitis was induced by acetic acid (AA). Nadroparin sodium was given to prevention and treatment groups in addition to AA. Colitis was assessed histologically and levels of proteins were analyzed with Western blot. Nadroparin not only prevented and ameliorated the AA-induced colitis histopathologically but also decreased expression of colon NF-κB, activator protein-1, cyclooxygenase-2, tumor necrosis factor-alpha, and IL-6, which were significantly increased in group AA compared to control. The accumulation of Nrf2 in nuclear fraction and HO-1 found low in group AA was increased with nadroparin (p < 0.05). The mean malondialdehyde level increased with AA and was decreased significantly with nadroparin prevention and treatment (p < 0.001). Nadroparin sodium has both protective and therapeutic effects against colonic inflammation via exerting anti-oxidative and anti-inflammatory effects by modulating Nrf2/HO-1 and NF-κB pathways.

  3. 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.

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

    Science.gov (United States)

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

    2016-01-01

    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. 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. 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). 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.

  5. 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.

  6. Niacinamide mitigated the acute lung injury induced by phorbol myristate acetate in isolated rat's lungs.

    Science.gov (United States)

    Lin, Chia-Chih; Hsieh, Nan-Kuang; Liou, Huey Ling; Chen, Hsing I

    2012-03-01

    Phorbol myristate acetate (PMA) is a strong neutrophil activator and has been used to induce acute lung injury (ALI). Niacinamide (NAC) is a compound of B complex. It exerts protective effects on the ALI caused by various challenges. The purpose was to evaluate the protective effects of niacinamide (NAC) on the PMA-induced ALI and associated changes. The rat's lungs were isolated in situ and perfused with constant flow. A total of 60 isolated lungs were randomized into 6 groups to received Vehicle (DMSO 100 μg/g), PMA 4 μg/g (lung weight), cotreated with NAC 0, 100, 200 and 400 mg/g (lung weight). There were 10 isolated lungs in each group. We measured the lung weight and parameters related to ALI. The pulmonary arterial pressure and capillary filtration coefficient (Kfc) were determined in isolated lungs. ATP (adenotriphosphate) and PARP [poly(adenosine diphophate-ribose) polymerase] contents in lung tissues were detected. Real-time PCR was employed to display the expression of inducible and endothelial NO synthases (iNOS and eNOS). The neutrophil-derived mediators in lung perfusate were determined. PMA caused increases in lung weight parameters. This agent produced pulmonary hypertension and increased microvascular permeability. It resulted in decrease in ATP and increase in PARP. The expression of iNOS and eNOS was upregulated following PMA. PMA increased the neutrophil-derived mediators. Pathological examination revealed lung edema and hemorrhage with inflammatory cell infiltration. Immunohistochemical stain disclosed the presence of iNOS-positive cells in macrophages and endothelial cells. These pathophysiological and biochemical changes were diminished by NAC treatment. The NAC effects were dose-dependent. Our results suggest that neutrophil activation and release of neutrophil-derived mediators by PMA cause ALI and associated changes. NO production through the iNOS-producing cells plays a detrimental role in the PMA-induced lung injury. ATP is beneficial

  7. Niacinamide mitigated the acute lung injury induced by phorbol myristate acetate in isolated rat's lungs

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    Lin Chia-Chih

    2012-03-01

    Full Text Available Abstract Background Phorbol myristate acetate (PMA is a strong neutrophil activator and has been used to induce acute lung injury (ALI. Niacinamide (NAC is a compound of B complex. It exerts protective effects on the ALI caused by various challenges. The purpose was to evaluate the protective effects of niacinamide (NAC on the PMA-induced ALI and associated changes. Methods The rat's lungs were isolated in situ and perfused with constant flow. A total of 60 isolated lungs were randomized into 6 groups to received Vehicle (DMSO 100 μg/g, PMA 4 μg/g (lung weight, cotreated with NAC 0, 100, 200 and 400 mg/g (lung weight. There were 10 isolated lungs in each group. We measured the lung weight and parameters related to ALI. The pulmonary arterial pressure and capillary filtration coefficient (Kfc were determined in isolated lungs. ATP (adenotriphosphate and PARP [poly(adenosine diphophate-ribose polymerase] contents in lung tissues were detected. Real-time PCR was employed to display the expression of inducible and endothelial NO synthases (iNOS and eNOS. The neutrophil-derived mediators in lung perfusate were determined. Results PMA caused increases in lung weight parameters. This agent produced pulmonary hypertension and increased microvascular permeability. It resulted in decrease in ATP and increase in PARP. The expression of iNOS and eNOS was upregulated following PMA. PMA increased the neutrophil-derived mediators. Pathological examination revealed lung edema and hemorrhage with inflammatory cell infiltration. Immunohistochemical stain disclosed the presence of iNOS-positive cells in macrophages and endothelial cells. These pathophysiological and biochemical changes were diminished by NAC treatment. The NAC effects were dose-dependent. Conclusions Our results suggest that neutrophil activation and release of neutrophil-derived mediators by PMA cause ALI and associated changes. NO production through the iNOS-producing cells plays a detrimental

  8. 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

  9. Apigenin induces apoptosis and blocks growth of medroxyprogesterone acetate-dependent BT-474 xenograft tumors.

    Science.gov (United States)

    Mafuvadze, Benford; Liang, Yayun; Besch-Williford, Cynthia; Zhang, Xu; Hyder, Salman M

    2012-08-01

    Recent clinical and epidemiological evidence shows that hormone replacement therapy (HRT) containing both estrogen and progestin increases the risk of primary and metastatic breast cancer in post-menopausal women while HRT containing only estrogen does not. We and others previously showed that progestins promote the growth of human breast cancer cells in vitro and in vivo. In this study, we sought to determine whether apigenin, a low molecular weight anti-carcinogenic flavonoid, inhibits the growth of aggressive Her2/neu-positive BT-474 xenograft tumors in nude mice exposed to medroxyprogesterone acetate (MPA), the most commonly used progestin in the USA. Our data clearly show that apigenin (50 mg/kg) inhibits progression and development of these xenograft tumors by inducing apoptosis, inhibiting cell proliferation, and reducing expression of Her2/neu. Moreover, apigenin reduced levels of vascular endothelial growth factor (VEGF) without altering blood vessel density, indicating that continued expression of VEGF may be required to promote tumor cell survival and maintain blood flow. While previous studies showed that MPA induces receptor activator of nuclear factor kappa-B ligand (RANKL) expression in rodent mammary gland, MPA reduced levels of RANKL in human tumor xenografts. RANKL levels remained suppressed in the presence of apigenin. Exposure of BT-474 cells to MPA in vitro also resulted in lower levels of RANKL; an effect that was independent of progesterone receptors since it occurred both in the presence and absence of the antiprogestin RU-486. In contrast to our in vivo observations, apigenin protected against MPA-dependent RANKL loss in vitro, suggesting that MPA and apigenin modulate RANKL levels differently in breast cancer cells in vivo and in vitro. These preclinical findings suggest that apigenin has potential as an agent for the treatment of progestin-dependent breast disease.

  10. 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.

  11. 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.

  12. Photothermolysis mediated by gold nanorods modified with EGFR monoclonal antibody induces Hep-2 cells apoptosis in vitro and in vivo.

    Science.gov (United States)

    Zhang, Shiwen; Li, Yunlong; He, Xiaoguang; Dong, Shouan; Huang, Yunchao; Li, Xiaojiang; Li, Yuxiao; Jin, Congguo; Zhang, Yingying; Wang, Yuanling

    2014-01-01

    Gold nanorods (AuNRs) have been used in plasmonic photothermal therapy (PPTT), which is thought to be more efficient and selective than conventional photothermal therapy. The efficiency and safety of PPTT can be improved by functionally modifying the gold nanorods with proteins or biomolecules. In this study, AuNRs were modified with anti-epidermal growth factor receptor (EGFR) monoclonal antibody (mAb), and the apoptotic potential of EGFRmAb-AuNR was assessed in Hep-2 cells in vitro and in vivo. The EGFRmAb modification had no obvious influence on the original optical property of the AuNRs, but it significantly increased the entry of AuNRs into Hep-2 cells. EGFRmAb-AuNRs, with appropriate laser irradiation, resulted in higher Hep-2 cells apoptosis than AuNRs did alone, in vitro, and was accompanied by alteration of reactive oxygen species (ROS) production, Ca(2+) release, change in mitochondrial membrane potential (ΔΨm), cytochrome c (Cyt-c) release, active caspase-3 expression, and level of B-cell lymphoma 2 (Bcl-2) and B-cell lymphoma 2 protein-associated X protein (Bax). EGFRmAb-AuNR-mediated apoptosis in Hep-2 cells was also observed in vivo and had an inhibitive effect on growth of Hep-2 tumor xenografts. Our data suggest that the EGFRmAb modification improves AuNR-mediated apoptosis and may have the potential to be used clinically.

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

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    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.

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

    Science.gov (United States)

    Guerreiro, Joana F.; Sampaio-Marques, Belém; Soares, Renata; Coelho, Ana V.; Leão, Cecília; Ludovico, Paula; Sá-Correia, Isabel

    2016-01-01

    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. PMID:28357336

  15. Oral Grapeseed Oil and Sesame Oil in Experimental Acetic Acid-Induced Ulcerative Colitis in Rat

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    Hosseinzadeh

    2016-06-01

    Full Text Available Background Ulcerative colitis (UC is a multi-factorial disease with unknown etiology and has many clinical manifestations. Objectives The current study aimed to evaluate the effects of sesame oil (SO and grapeseed oil (GSO on acetic acid-induced UC in rats. Materials and Methods Eighty male rats were divided into eight groups as health control (HC1, received normal saline; HC2, received SO; HC3, received GSO; negative control (NC, UC and normal saline; positive control (PC, UC and mesalamine; SO, UC and SO; GSO, UC and GSO, and SO + GSO. The daily weight changes, serum levels of oxidative stress markers and lipid profile plus colon macroscopic and microscopic histological changes were measured at the end of the seventh day. Results Significant differences were detected between HC1 and PC on the 3rd (P = 0.002, 4th (0.013 and 6th days (0.014 and between HC1 and NC on the 4th day (0.027 in weight of rats. Use of GSO alone or in combination with SO decreased the extent of the changes both in macroscopic and microscopic indices and also at the inflammation level. The most significant decrease in the MDA level and the most obvious increase in the TAC belonged to the GSO group in comparison to the NC group. The lowest cholesterol (51.43 ± 5.62 mg/dL and HDL levels (29.29 ± 6.24 mg/dL were detected in response to SO consumption in comparison to NC group (P = 0.030 and P = 0.257, respectively. Conclusions GSO in combination with SO may be considered as the treatment of choice for UC based on antioxidant and histopathological evaluations.

  16. Lupeol acetate ameliorates collagen-induced arthritis and osteoclastogenesis of mice through improvement of microenvironment.

    Science.gov (United States)

    Wang, Wei-Hsun; Chuang, Hui-Yen; Chen, Chien-Hui; Chen, Wun-Ke; Hwang, Jeng-Jong

    2016-04-01

    Lupeol has been shown with anti-inflammation and antitumor capability, however, the poor bioavailability limiting its applications in living subjects. Lupeol acetate (LA), a derivative of lupeol, shows similar biological activities as lupeol but with better bioavailability. Here RAW 264.7 cells and bone marrow-derived macrophages (BMDMs) stimulated by lipopolysaccharide (LPS) were treated with 0-80μM of LA, and assayed for TNF-α, IL-1β, COX-2, MCP-1 using Western blotting. Moreover, osteoclatogenesis was examined with reverse transcription PCR (RT-PCR) and tartrate-resistant acid phosphatase (TRAP) staining. For in vivo study, collagen-induced arthritis (CIA)-bearing DBA/1J mice were randomly separated into three groups: vehicle, LA-treated (50mg/kg) and curcumin-treated (100mg/kg). Therapeutic efficacies were assayed by the clinical score, expression levels of serum cytokines including TNF-α and IL-1β, (18)F-fluorodeoxyglucose ((18)F-FDG) microPET/CT and histopathology. The results showed that LA could inhibit the activation, migration, and formation of osteoclastogenesis of macrophages in a dose-dependent manner. In RA-bearing mice, the expressions of inflammation-related cytokines were suppressed, and clinical symptoms and bone erosion were ameliorated by LA. The accumulation of (18)F-FDG in the joints of RA-bearing mice was also significantly decreased by LA. The results indicate that LA significantly improves the symptoms of RA by down-regulating expressions of inflammatory cytokines and osteoclastogenesis.

  17. Extract of Salvadora persica roots attenuates lead acetate-induced testicular oxidative stress in rats

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    Gamal A. Soliman

    2017-08-01

    Full Text Available Context: Lead exerts pathological changes on male mammals. Deleterious effects on testicular tissues may be mediated by oxidative damage and subsequent lipid peroxidation. Medicinal plants can protect against such oxidative stress. Aims: To determine the protective activity of Salvadora persica, against lead acetate (LA testicular oxidative stress in rats. Methods: Adult male Wistar rats were allocated into six groups: control group received the vehicle, S. persica group received extract (500 mg/kg, LA group was exposed to 0.1% LA in drinking water and three other groups were co-treated with LA plus S. persica (125, 250 and 500 mg/kg. Treatments were applied for 60 days. Five days prior to the end of the experiment, male rats in all groups were mated with untreated females. Results: S. persica (500 mg/kg increased testosterone level and relative weights of testes, cauda epididymis and seminal vesicles in normal rats but did not affect testicular antioxidant parameters and sperm characteristics. Superoxide dismutase, glutathione peroxidase, catalase activities and the level of reduced glutathione were significantly reduced and malondialdehyde was elevated in the testicular homogenate of LA-exposed rats. LA exposure significantly reduced serum levels of testosterone, follicle-stimulating hormone and luteinizing hormone, as well as, sperm characteristics and relative weight of the testes, cauda epididymis, seminal vesicles and ventral prostate. Administration of S. persica extract (250 and 500 mg/kg significantly reduced oxidative stress and protected against LA-exposure effects. Conclusions: S. persica extract exhibited marked protective activity against LA-induced testicular oxidative stress in rats.

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

    Science.gov (United States)

    Verma, Neeraj; Singh, Anil P; Amresh, G; Sahu, P K; Rao, Ch V

    2011-05-01

    To evaluate the hepatoprotective potential of ethyl acetate fraction of Rhododendron arboreum (Family: Ericaceae) in Wistar rats against carbon tetrachloride (CCl(4))-induced liver damage in preventive and curative models. Fraction at a dose of 100, 200, and 400 mg/kg was administered orally once daily for 14 days in CCl(4)-treated groups (II, III, IV, V and VI). The serum levels of glutamic oxaloacetic transaminase (SGOT), glutamate pyruvate transaminase (SGPT), alkaline phosphatase (SALP), γ-glutamyltransferase (γ -GT), and bilirubin were estimated along with activities of glutathione S-transferase (GST), glutathione reductase, hepatic malondialdehyde formation, and glutathione content. 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.

  19. (-)-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.

  20. Zinc Chloride and Lead Acetate-Induced Passive Avoidance Memory Retention Deficits Reversed by Nicotine and Bucladesine in Mice.

    Science.gov (United States)

    Tabrizian, Kaveh; Yazdani, Abdolmajid; Baheri, Behnam; Payandemehr, Borna; Sanati, Mehdi; Hashemzaei, Mahmoud; Miri, Abdolhossein; Zandkarimi, Majid; Belaran, Maryam; Fanoudi, Sahar; Sharifzadeh, Mohammad

    2016-01-01

    It is very important to investigate the neurotoxic effects of metals on learning and memory processes. In this study, we tried to investigate the effects and time course properties of oral administration of zinc chloride (25, 50, and 75 mg/kg, for 2 weeks), lead acetate (250, 750, 1,500, and 2,500 ppm for 4, 6 and 8 weeks), and their possible mechanisms on a model of memory function. For this matter, we examined the intra-peritoneal injections of nicotine (0.25, 0.5, 1, and 1.5 mg/kg) and bucladesine (50, 100, 300, and 600 nM/mouse) for 4 days alone and in combination with mentioned metals in the step-through passive avoidance task. Control animals received saline, drinking water, saline, and DMSO (dimethyl sulfoxide)/deionized water (1:9), respectively. At the end of each part of studies, animals were trained for 1 day in step-through task. The avoidance memory retention alterations were evaluated 24 and 48 h later in singular and combinational studies. Zinc chloride (75 mg/kg) oral gavage for 2 weeks decreased latency times compared to control animals. Also, lead acetate (750 ppm oral administrations for 8 weeks) caused significant lead blood levels and induced avoidance memory retention impairments. Four-days intra-peritoneal injection of nicotine (1 mg/kg) increased latency time compared to control animals. Finally, findings of this research showed that treatment with intra-peritoneal injections of nicotine (1 mg/kg) and/or bucladesine (600 nM/mouse) reversed zinc chloride- and lead acetate-induced avoidance memory retention impairments. Taken together, these results showed the probable role of cholinergic system and protein kinase A pathways in zinc chloride- and lead acetate-induced avoidance memory alterations.

  1. Mitochondria defects are involved in lead-acetate-induced adult hematopoietic stem cell decline.

    Science.gov (United States)

    Liu, Jun; Jia, Dao-Yong; Cai, Shi-Zhong; Li, Cheng-Peng; Zhang, Meng-Si; Zhang, Yan-Yan; Yan, Chong-Huai; Wang, Ya-Ping

    2015-05-19

    Occupational high-grade lead exposure has been reduced in recent decades as a result of increased regulation. However, environmental lead exposure remains widespread, and is associated with severe toxicity implicated in human diseases. We performed oral intragastric administration of various dose lead acetate to adult Sprague Dawley rats to define the role of lead exposure in hematopoietic stem cells (HSCs) function, and to clarify its underlying mechanism. Lead acetate-exposed rats exhibited developmental abnormalities in myeloid and lymphoid lineages, and a significant decline in immune functions. It also showed HSCs functional decline associated with senescent phenotype with low grade lead acetate exposure or apoptotic phenotype with relative higher grade dose exposure. Mechanistic exploration showed a significant increase in reactive oxygen species (ROS) in the lead acetate-exposed CD90(+)CD45(-) compartment, which correlated with functional defects in cellular mitochondria. Furthermore, in vivo treatment with the antioxidant vitamin C led to reversion of the CD90(+)CD45(-) compartment functional decline. These results indicate that lead acetate perturbs the hematopoietic balance of adult HSCs, associated with cellular mitochondria defects, increased intracellular ROS generation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. 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

  3. Photothermolysis mediated by gold nanorods modified with EGFR monoclonal antibody induces Hep-2 cells apoptosis in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Zhang S

    2014-04-01

    Full Text Available Shiwen Zhang,1,2,* Yunlong Li,3,4,* Xiaoguang He,2 Shouan Dong,5 Yunchao Huang,6 Xiaojiang Li,1 Yuxiao Li,2 Congguo Jin,7 Yingying Zhang,8 Yuanling Wang91Department of Head and Neck, The Third Affiliated Hospital of Kunming Medical University (Tumor Hospital of Yunnan Province, Kunming, 2Department of Head and Neck, The First Affiliated Hospital of Kunming Medical University, Kunming, 3Medical Faculty, Kunming University of Science and Technology, Kunming, 4The First People's Hospital of Yunnan Province (The Affiliated Hospital of Kunming University of Science and Technology, Kunming, 5Kunming Institute of Precious Metals, Kunming, 6Department of cardiothoracic surgery, The Third Affiliated Hospital of Kunming Medical University (Tumor Hospital of Yunnan Province, Kunming, 7Institute of Oncology, The Third Affiliated Hospital of Kunming Medical University (Tumor Hospital of Yunnan Province, Kunming, 8Clinical skills training center of Kunming Medical University, Kunming, 9Department of Anesthesiology, Yan An Hospital, Kunming, Yunnan, The People's Republic of China *These authors contributed equally to this workAbstract: Gold nanorods (AuNRs have been used in plasmonic photothermal therapy (PPTT, which is thought to be more efficient and selective than conventional photothermal therapy. The efficiency and safety of PPTT can be improved by functionally modifying the gold nanorods with proteins or biomolecules. In this study, AuNRs were modified with anti-epidermal growth factor receptor (EGFR monoclonal antibody (mAb, and the apoptotic potential of EGFRmAb-AuNR was assessed in Hep-2 cells in vitro and in vivo. The EGFRmAb modification had no obvious influence on the original optical property of the AuNRs, but it significantly increased the entry of AuNRs into Hep-2 cells. EGFRmAb-AuNRs, with appropriate laser irradiation, resulted in higher Hep-2 cells apoptosis than AuNRs did alone, in vitro, and was accompanied by alteration of reactive oxygen

  4. Implication of limonene and linalyl acetate in cytotoxicity induced by bergamot essential oil in human neuroblastoma cells.

    Science.gov (United States)

    Russo, Rossella; Ciociaro, Antonella; Berliocchi, Laura; Cassiano, Maria Gilda Valentina; Rombolà, Laura; Ragusa, Salvatore; Bagetta, Giacinto; Blandini, Fabio; Corasaniti, Maria Tiziana

    2013-09-01

    Bergamot (Citrus bergamia, Risso et Poiteau) essential oil (BEO) is a widely used plant extract showing anxiolytic, analgesic and neuroprotective effects in rodents; also, BEO activates multiple death pathways in cancer cells. Despite detailed knowledge of its chemical composition, the constituent/s responsible for these pharmacological activities remain largely unknown. Aim of the present study was to identify the components of BEO implicated in cell death. To this end, limonene, linalyl acetate, linalool, γ-terpinene, β-pinene and bergapten were individually tested in human SH-SY5Y neuroblastoma cultures at concentrations comparable with those found in cytotoxic dilutions of BEO. None of the tested compounds elicited cell death. However, significant cytotoxicity was observed when cells were cotreated with limonene and linalyl acetate whereas no other associations were effective. Only cotreatment, but not the single exposure to limonene and linalyl acetate, replicated distinctive morphological and biochemical changes induced by BEO, including caspase-3 activation, PARP cleavage, DNA fragmentation, cell shrinkage, cytoskeletal alterations, together with necrotic and apoptotic cell death. Collectively, our findings suggest a major role for a combined action of these monoterpenes in cancer cell death induced by BEO.

  5. Antioxidant and Protective Effect of Ethyl Acetate Extract of Podophyllum hexandrum Rhizome on Carbon Tetrachloride Induced Rat Liver Injury

    Directory of Open Access Journals (Sweden)

    Showkat Ahmad Ganie

    2011-01-01

    Full Text Available The antioxidant and hepatoprotective activities of ethyl acetate extract was carefully investigated by the methods of DPPH radical scavenging activity, Hydroxyl radical scavenging activity, superoxide radical scavenging activity, hydrogen peroxide radical scavenging activity, and its reducing power ability. All these in vitro antioxidant activities were concentration dependent, which were compared with standard antioxidants such as BHT, α-tocopherol. The hepatoprotective potential of Podophyllum hexandrum extract was also evaluated in male Wistar rats against carbon tetrachloride- (CCl4- induced liver damage. Pretreated rats were given ethyl acetate extract at 20, 30, and 50 mg/kg dose prior to CCl4 administration (1 mL/kg, 1:1 in olive oil. Rats pretreated with P. hexandrum extract remarkably prevented the elevation of serum AST, ALT, LDH, and liver lipid peroxides in CCl4-treated rats. Hepatic glutathione levels were significantly increased by the treatment with the extract in all the experimental groups. The extract at the tested doses also restored the levels of liver homogenate enzymes (glutathione peroxidase, glutathione reductase, superoxide dismutase, and glutathione-S-transferase significantly. This study suggests that ethyl acetate extract of P. hexandrum has a liver-protective effect against CCl4-induced hepatotoxicity and possess in vitro antioxidant activities.

  6. Photocatalyst-Free and Blue Light-Induced RAFT Polymerization of Vinyl Acetate at Ambient Temperature.

    Science.gov (United States)

    Ding, Chunlai; Fan, Caiwei; Jiang, Ganquan; Pan, Xiangqiang; Zhang, Zhengbiao; Zhu, Jian; Zhu, Xiulin

    2015-12-01

    Vinyl acetate is polymerized in the living way under the irradiation of blue light-emitting diodes (LEDs) or sunlight without photocatalyst at ambient temperature. 2-(Ethoxycarbonothioyl)sulfanyl propanoate is exclusively added and acts as initiator and chain transfer agent simultaneously in the current system. Poly(vinyl acetate) with well-regulated molecular weight and narrow molecular weight distribution (Đ < 1.30) is synthesized. Near quantitative end group fidelity of polymer is demonstrated by nuclear magnetic resonance (NMR) and matrix-assisteed laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).

  7. 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.

  8. 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.

  9. The Epidermal Growth Factor Receptor (EGFR) Inhibitor Gefitinib Reduces but Does Not Prevent Tumorigenesis in Chemical and Hormonal Induced Hepatocarcinogenesis Rat Models

    OpenAIRE

    Silvia Ribback; Verena Sailer; Enrico Böhning; Julia Günther; Jaqueline Merz; Frauke Steinmüller; Kirsten Utpatel; Antonio Cigliano; Kristin Peters; Pilo, Maria G.; Matthias Evert; Calvisi, Diego F.; Frank Dombrowski

    2016-01-01

    Activation of the epidermal growth factor receptor (EGFR) signaling pathway promotes the development of hepatocellular adenoma (HCA) and carcinoma (HCC). The selective EGFR inhibitor Gefitinib was found to prevent hepatocarcinogenesis in rat cirrhotic livers. Thus, Gefitinib might reduce progression of pre-neoplastic liver lesions to HCC. In short- and long-term experiments, administration of N-Nitrosomorpholine (NNM) or intrahepatic transplantation of pancreatic islets in diabetic (PTx), thy...

  10. 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.

  11. 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.

  12. EGFR在TGFβ1诱导Ⅱ型肺泡上皮细胞转分化中的作用%Effect of EGFR on epithelial-mesenchymal transition of type Ⅱ alveolar epithelial cells induced by TGFβ1

    Institute of Scientific and Technical Information of China (English)

    蔡琳; 阮志燕

    2012-01-01

    目的 探讨表皮生长因子受体(EGFR)在转分化因子β1(TGFβ1)体外诱导Ⅱ型肺泡上皮细胞转分化中的作用.方法 体外培养Ⅱ型肺泡上皮细胞系细胞-A549细胞,以TGFβ1刺激,倒置相差显微镜观察细胞形态学的变化;收集不同时段的细胞,应用RT-PCR检测TGFβ1干预前后E-钙黏蛋白(E-cadherin)和α平滑肌肌动蛋白(α-SMA)mRNA表达变化;Western blot观察E-cad、α-SMA和信号转导蛋白EGFR表达的变化.结果 倒置相差显微镜观察到TGFβ1刺激后A549细胞由鹅卵石状变为梭形,形态如同肌成纤维细胞;TGFβ1刺激A549细胞能导致E-cadherin mRNA和蛋白表达下调;α-SMA mRNA和蛋白表达上调;磷酸化EGFR(p-EGFR)表达上调.结论 TGFβ1能在体外诱导肺泡上皮细胞向间质细胞转分化,其机制与EGFR信号通路的活化相关.抑制EGFR的活化可能为临床防治肺纤维化提供新的途径.%Objective To investigate the effect of epidermal growth fart or receptor ( EGFR ) expression on epithelial-mesenchy-mal transition ( EMT ) of type Ⅱ alveolar epithelial cells induced by TGFβ1 . Methods The in vitro cultured type fl alveolar epithelial cell line-A549 cells were treated with TGFpl at different time points to observe its cellular morphology changes under phase-contrast micro scope. The cells at different time point were collected to assay mRNA expression of E-cadherin and ?smooth muscle actin ( a-SMA ) by RT-PCR before and after A549 cells being treated by TGFpl , and protein expression of E-cadherin, a-SMA and phosphorylated EGFR ( p-EGFR ) were detected by Western blot. Results After TGFpl treatment, A549 cells were turned from cobblestone into spindle-shaped , a myofibroblast-like morphology. Protein and mRNA expression of E-cadherin were down regulated ( P < 0. 05 ) , but protein and mRNA expression of a-tSMA and p-EGFR were up regulated ( P < 0. 05 ). Conclusion TGFpl can induce EMT of alveolar- epithelial cells in vitro, where the

  13. 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. © 2016 Institute of Food Technologists®

  14. Effect of piperine on inhibition of FFA induced TLR4 mediated inflammation and amelioration of acetic acid induced ulcerative colitis in mice.

    Science.gov (United States)

    Gupta, Rohit A; Motiwala, Meha N; Dumore, Nitin G; Danao, Kishor R; Ganjare, Anjali B

    2015-04-22

    Piperine, a main component of Piper longum Linn. and Piper nigrum Linn., is a plant alkaloid with a long history of medicinal use. Piperine exhibits antidepressant, hepatoprotective, anti-metastatic, anti-thyroid, immunomodulatory, antitumor and anti-inflammatory activities, However its therapeutic potential in amelioration of ulcerative colitis and the underlying mechanism for anti-inflammatory activity remains unknown.The objective of the present investigation was to unravel the therapeutic potential of piperine on amelioration of IBD using acetic acid induced experimental animal model for ulcerative colitis and to determine the role of TLR4 receptor in signalling pathway of inflammatory gene expression in ulcerative colitis. We induced colitis using acetic acid (150µl of 5% once, intrarectally) in mice and estimated disease activity index (DAI), which took into account weight loss, stool consistency, and occult/gross bleeding. Colon length, spleen weights, ulcer area and ulcer index were measured; histological changes were observed by H&E staining. Effect of piperine on various antioxidant parameter of mice colon such as tissue myeloperoxidase (MPO) accumulation, SOD concentrations, reduced GSH and lipid peroxidation were determined. Pro-inflammatory mediators, namely, nitric oxide (NO), tumour necrosis factor-α (TNF-α) were determined by a TNF-α ELISA kit obtained from Thermo fisher scientific India Pvt. Ltd. Effect of piperine on haematological parameters of mice in acetic acid induced IBD was also determined which involves the estimation of FFA using a commercial free fatty acid fluorometric assay kit. Piperine significantly attenuated acetic acid induced DAI score which implies that it suppresses weight loss, diarrhoea, gross bleeding and infiltration of immune cells. Piperine administration also effectively and dose dependently prevented shortening of colon length and enlargement of spleen size. Histological examination indicated that piperine reduces

  15. Der p, IL-4, and TGF-beta cooperatively induce EGFR-dependent TARC expression in airway epithelium

    NARCIS (Netherlands)

    Heijink, Irene; Kies, P. Marcel; van Oosterhout, Antoon J. M.; Postma, Dirkje S.; Kauffman, Henk F.; Vellenga, Edo

    Thymus and Activation-Regulated Chemokine (TARC) may be critical in Th2 cell recruitment in allergic inflammation; however, the mechanisms of allergen-induced TARC release are unclear. Since airway epithelium is the first line of defense to inhaled allergens, we questioned whether house dust mite

  16. Aberrant trafficking of NSCLC-associated EGFR mutants through the endocytic recycling pathway promotes interaction with Src@

    Directory of Open Access Journals (Sweden)

    Band Vimla

    2009-11-01

    Full Text Available Abstract Background Epidermal growth factor receptor (EGFR controls a wide range of cellular processes, and altered EGFR signaling contributes to human cancer. EGFR kinase domain mutants found in non-small cell lung cancer (NSCLC are constitutively active, a trait critical for cell transformation through activation of downstream pathways. Endocytic trafficking of EGFR is a major regulatory mechanism as ligand-induced lysosomal degradation results in termination of signaling. While numerous studies have examined mutant EGFR signaling, the endocytic traffic of mutant EGFR within the NSCLC milieu remains less clear. Results This study shows that mutant EGFRs in NSCLC cell lines are constitutively endocytosed as shown by their colocalization with the early/recycling endosomal marker transferrin and the late endosomal/lysosomal marker LAMP1. Notably, mutant EGFRs, but not the wild-type EGFR, show a perinuclear accumulation and colocalization with recycling endosomal markers such as Rab11 and EHD1 upon treatment of cells with endocytic recycling inhibitor monensin, suggesting that mutant EGFRs preferentially traffic through the endocytic recycling compartments. Importantly, monensin treatment enhanced the mutant EGFR association and colocalization with Src, indicating that aberrant transit through the endocytic recycling compartment promotes mutant EGFR-Src association. Conclusion The findings presented in this study show that mutant EGFRs undergo aberrant traffic into the endocytic recycling compartment which allows mutant EGFRs to engage in a preferential interaction with Src, a critical partner for EGFR-mediated oncogenesis.

  17. Calcium acetate induces calcium uptake and formation of calcium-oxalate crystals in isolated leaflets of Gleditsia triacanthos L.

    Science.gov (United States)

    Borchert, R

    1986-09-01

    During treatment of isolated, peeled leaflets of Gleditsia triacanthos with 0.5-2 mM [(45)Ca]acetate, saturation of the cell-wall free space with Ca(2+) occurred within 10 min and was followed by a period of 6-10 h during which there was no significant Ca-uptake into the protoplast, but apoplastic Ca(2+) was periodically released into the medium. Later, Ca(2+) was absorbed for 3-4 d at rates of up to 2.2 μmol Ca(2+)·h(-1)·(g FW)(-1) to final concentrations of 350 μmol Ca(2+)· (g FW)(-1). The distribution of absorbed Ca(2+) between cell wall, vacuole and Ca-oxalate crystals was determined during Ca-uptake. Wheras intact, cut leaflets deposited absorbed Ca(2+) as Ca-oxalate in the crystal cells, peeled leaflets lacking crystal cells accumulated at least 40-50 μmol·(g FW)(-1) soluble Ca(2+) before the absorbed Ca(2+) was precipitated as Ca-oxalate. These observations indicate that the mechanisms for the continuous uptake of Ca(2+), the synthesis of oxalate and the precipitation of Ca(2+) as Ca-oxalate are operational in the crystal cells of intact leaflets, but not in the mesophyll cells of peeled leaflets where they must be induced by exposure to Ca(2+). The precipitation of absorbed Ca(2+) as Ca-oxalate by the crystal cells of isolated Gleditsia leaflets illustrates the role of these cells in the excretion of surplus Ca(2+) which enters normal, attached leaves with the transpiration stream.In addition to acetate, only Ca-lactate and Ca-carbonate lead to Ca-uptake, but at rates well below those observed with Ca-acetate. Other small organic anions (citrate, glycolate, glyoxalate, malate) and inorganic anions (chloride, nitrate, sulfate) did not permit Ca-uptake. Acetate-(14)C was rapidly absorbed during Ca-uptake, but less than 20% was incorporated into Ca-oxalate; the rest remained mostly in the soluble fraction or was metabolized to CO2. Acetate, as a permeable weak acid, may enable rapid Ca-uptake by stimulating proton extrusion at the plasmalemma and by

  18. 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...

  19. The bryostatin 1 A-ring acetate is not the critical determinant for antagonism of phorbol ester-induced biological responses.

    Science.gov (United States)

    Keck, Gary E; Li, Wei; Kraft, Matthew B; Kedei, Noemi; Lewin, Nancy E; Blumberg, Peter M

    2009-06-04

    The contribution of the A-ring C(7) acetate to the function of bryostatin 1 has been investigated through synthesis and biological evaluation of an analogue incorporating this feature into the bryopyran core structure. No enhanced binding affinity for protein kinase C (PKC) was observed, relative to previously characterized analogues lacking the C(7) acetate. Functional assays showed biological responses characteristic of those induced by the phorbol ester PMA and distinctly different from those observed with bryostatin 1.

  20. 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.

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

    Science.gov (United States)

    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 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.

  2. The protective effect of Echinacea spp. (Echinacea angustifolia and Echinacea purpurea) in a rat colitis model induced by acetic acid.

    Science.gov (United States)

    Dogan, Zeynal; Ergul, Bilal; Sarikaya, Murat; Filik, Levent; Gonultaş, Mehmet Alparslan; Hucumenoglu, Sema; Can, Murat

    2014-11-01

    Ulcerative colitis (UC) is a chronic disease that causes an inflammatory condition in the colon. Several cytokines, including tumor necrosis factor alpha (TNF-α), interleukin 1 beta (IL-1β) and transforming growth factor beta (TGF-β) are crucial components of these inflammatory pathways. New therapeutic strategies are needed for improved clinical outcomes in UC and with less adverse effects. That is why alternative therapies such as herbal remedies are increasingly being used with favorable effects in the treatment of UC. Hence, in the present study, we aimed to evaluate the protective effect of Echinacea spp in an experimental rat colitis model induced by acetic acid (AA). Acetic acid was given via a rectal route to induce acute colitis in rats. Rats were placed in four groups: control, Echinacea, Echinacea-colitis and colitis. Tumor necrosis factor alpha, IL-1β and TGF-β levels were measured. Histopathological comparison of the groups was also performed. The disease activity index (DAI) was significantly higher in the colitis group compared to the control, Echinacea and Echinacea-colitis groups (pEchinacea and Echinacea-colitis groups (p>0.07). The inflammatory mediators IL-1β and TNF-α were significantly elevated in the colitis group compared to the other groups (pEchinacea spp. may likely have some therapeutic favorable effects in the management of UC.

  3. The antioxidant effect of Echinacea angustifolia and Echinacea purpurea in rat colitis model induced by acetic acid.

    Science.gov (United States)

    Dogan, Z; Ergul, B; Sarikaya, M; Filik, L; Gonultas, M Alparslan; Hucumenoglu, S; Can, M

    2014-01-01

    Ulcerative colitis is a chronic inflammatory condition of the colon, and reactive oxidative metabolites (ROMs) play an important role in its pathogenesis. Alternative therapies such as herbal remedies are increasingly being used in the treatment of ulcerative colitis for better clinical outcome of ulcerative colitis and less adverse effects. Echinacea has many features including antioxidant and wound-healing properties. Hence, the present study was undertaken to evaluate the protective effect of Echinacea spp. on experimental colitis model induced by acetic acid in Wistar albino rats. Acute colitis was induced by intrarectal administration of acetic acid. Rats were divided into four groups, namely control, Echinacea-administered, Echinacea-administered-colitis and colitis. Malondialdehyde and total antioxidant status were assayed in tissue samples. Histopathological evaluation was also performed. Macroscopic and microscopic scores were significantly higher in colitis group compared to control, Echinacea and Echinacea-colitis groups (p Echinacea and Echinacea-colitis groups (p > 0.3, p > 0.22). Malondialdehyde levels were elevated in colitis group compared to other groups (p Echinacea group compared with other groups and also significantly higher in Echinacea-colitis group compared with colitis group (p Echinacea may possibly have some therapeutic usefulness in the management of ulcerative colitis (Tab. 2, Fig. 4, Ref. 35).

  4. Regulation of EGFR protein stability by the HECT-type ubiquitin ligase SMURF2.

    Science.gov (United States)

    Ray, Dipankar; Ahsan, Aarif; Helman, Abigail; Chen, Guoan; Hegde, Ashok; Gurjar, Susmita Ramanand; Zhao, Lili; Kiyokawa, Hiroaki; Beer, David G; Lawrence, Theodore S; Nyati, Mukesh K

    2011-07-01

    Epidermal growth factor receptor (EGFR) is overexpressed in a variety of epithelial tumors and is considered to be an important therapeutic target. Although gene amplification is responsible for EGFR overexpression in certain human malignancies including lung and head and neck cancers, additional molecular mechanisms are likely. Here, we report a novel interaction of EGFR with an HECT-type ubiquitin ligase SMURF2, which can ubiquitinate, but stabilize EGFR by protecting it from c-Cbl-mediated degradation. Conversely, small interfering RNA (siRNA)-mediated knockdown of SMURF2 destabilized EGFR, induced an autophagic response and reduced the clonogenic survival of EGFR-expressing cancer cell lines, with minimal effects on EGFR-negative cancer cells, normal fibroblasts, and normal epithelial cells. UMSCC74B head and neck squamous cancer cells, which form aggressive tumors in nude mice, significantly lost in vivo tumor-forming ability on siRNA-mediated SMURF2 knockdown. Gene expression microarray data from 443 lung adenocarcinoma patients, and tissue microarray data from 67 such patients, showed a strong correlation of expression between EGFR and SMURF2 at the messenger RNA and protein levels, respectively. Our findings suggest that SMURF2-mediated protective ubiquitination of EGFR may be responsible for EGFR overexpression in certain tumors and support targeting SMURF2-EGFR interaction as a novel therapeutic approach in treating EGFR-addicted tumors.

  5. Regulation of EGFR Protein Stability by the HECT-type Ubiquitin Ligase SMURF2

    Directory of Open Access Journals (Sweden)

    Dipankar Ray

    2011-07-01

    Full Text Available Epidermal growth factor receptor (EGFR is overexpressed in a variety of epithelial tumors and is considered to be an important therapeutic target. Although gene amplification is responsible for EGFR overexpression in certain human malignancies including lung and head and neck cancers, additional molecular mechanisms are likely. Here, we report a novel interaction of EGFR with an HECT-type ubiquitin ligase SMURF2, which can ubiquitinate, but stabilize EGFR by protecting it from c-Cbl-mediated degradation. Conversely, small interfering RNA (siRNA-mediated knockdown of SMURF2 destabilized EGFR, induced an autophagic response and reduced the clonogenic survival of EGFR-expressing cancer cell lines, with minimal effects on EGFR-negative cancer cells, normal fibroblasts, and normal epithelial cells. UMSCC74B head and neck squamous cancer cells, which form aggressive tumors in nudemice, significantly lost in vivo tumor-forming ability on siRNA-mediated SMURF2 knockdown. Gene expressionmicroarray data from 443 lung adenocarcinoma patients, and tissue microarray data from 67 such patients, showed a strong correlation of expression between EGFR and SMURF2 at the messenger RNA and protein levels, respectively. Our findings suggest that SMURF2-mediated protective ubiquitination of EGFR may be responsible for EGFR overexpression in certain tumors and support targeting SMURF2-EGFR interaction as a novel therapeutic approach in treating EGFR-addicted tumors.

  6. 1'-Acetoxychavicol acetate-induced cytotoxicity is accompanied by a rapid and drastic modulation of glutathione metabolism.

    Science.gov (United States)

    Higashida, Mami; Xu, Shenghui; Kojima-Yuasa, Akiko; Kennedy, David Opare; Murakami, Akira; Ohigashi, Hajime; Matsui-Yuasa, Isao

    2009-01-01

    The effect of 1'-acetoxychavicol acetate (ACA), an anticarcinogenic compound naturally obtained from rhizomes and seeds of South East Asia plants, on the intracellular concentration of glutathione and the activities of enzymes related to glutathione metabolism was studied in Ehrlich ascites tumor cells. We showed in a previous study that ACA induced apoptosis in tumor cells and the cell death was reversed by the addition of N-acetlycysteine or glutathione ethylester. Here we found that ACA caused a rapid decrease in glutathione level in less than 10 min after ACA exposure. At the time, glutathione reductase activity was significantly inhibited and gamma-glutamyl cysteine increased by ACA exposure. These results show that ACA caused the decrease in the intracellular GSH levels in Ehrlich ascites tumor cells, suggesting that ACA-induced decrease of the cellular GSH levels can lead to growth arrest of cancer and enhancement of the efficacy other anticancer drugs.

  7. Modulation by cyclic AMP and phorbol myristate acetate of cephaloridine-induced injury in rat renal cortical slices.

    Science.gov (United States)

    Kohda, Y; Gemba, M

    2001-01-01

    Intracellular signaling pathways of cAMP and protein kinase C (PKC) have been suggested to modulate the generation of free radicals. We investigated the effects of cAMP and phorbol myristate acetate (PMA), a PKC activator, on cephaloridine (CER)-induced renal cell injury, which has been reported to be due to the generation of free radicals. Incubation of rat renal cortical slices with CER resulted in increases in lipid peroxidation and lactate dehydrogenase (LDH) release and in decreases in gluconeogenesis and p-aminohippurate (PAH) accumulation in rat renal cortical slices, suggesting free radical-induced injury in slices exposed to CER. A derivative of cAMP ameliorated not only the increase in lipid peroxidation but also the renal cell damage induced by CER. This amelioration by a cAMP derivative of lipid peroxidation and renal cell damage caused by CER was blocked by KT 5720, a protein kinase A (PKA) inhibitor. Lipid peroxidation and the indices of cell injury were increased by PMA. PMA also enhanced CER-induced lipid peroxidation and cell damage in the slices. This enhancement by PMA of CER-induced injury was blocked by H-7, a PKC inhibitor. These results indicated that intracellular signaling pathways of cAMP and PKC modulate free radical-mediated nephrotoxicity induced by CER.

  8. 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.

  9. Fucoidan as an inhibitor of thermally induced collagen glycation examined by acetate electrophoresis.

    Science.gov (United States)

    Pielesz, Anna; Paluch, Jadwiga

    2014-08-01

    Non-enzymatic glycation (Maillard reaction) in vitro could be a simple method to obtain glycoconjugates for studying their biological properties. Hence, fucoidan was retained by acetate electrophoresis indicating a strong interaction with the protein. A loss of colour in fucoidan bands was found for samples incubated with collagen as compared with samples of free fucoidan. Also under in vitro conditions at 100°C - simulating a sudden burn incident - fucoidan binds with collagen as a result of the Maillard reaction. In contrast, the colour of the fucoidan bands intensified for samples incubated with collagen, with the addition of glucose. Electrophoretic analyses were carried out after heating the samples to a temperature simulating a burn incident. The bands were found to intensify for samples incubated with collagen during a 30-day-long incubation. Thus, spontaneous in vitro glycation - i.e. without the addition of glucose - was confirmed. This process is highly intensified both by the temperature and time of incubation. For a sample incubated in vitro in a fucoidan solution containing glucose, glycation was confirmed in a preliminary FTIR and acetate electrophoresis examinations, occurring in collagen obtained from chicken skins. In particular, a new band emerging around 1746 cm(-1) was observed for above samples, as was its increasing intensity, as compared with samples without the addition of glucose. In the collagen glycation assay, while glucose reacts with collagen and forms cross-linked aggregates, fucoidan decreases the process of aggregation and recovery of native collagen.

  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. 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.

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

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    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.

  13. Aspirin-Induced Gastric Lesions Alters EGFR and PECAM-1 Immunoreactivity in Wistar Rats: Modulatory Action of Flavonoid Fraction of Musa Paradisiaca

    Directory of Open Access Journals (Sweden)

    Margaret Olutayo Alese

    2017-07-01

    CONCLUSION: The efficacy of Musa paradisiaca in attenuating the damaging effects of aspirin on the gastric mucosa was observed as there was a significantly increased reactivity for EGFR and PECAM-1 in the gastric corpus in a dose-dependent manner.

  14. 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.

  15. Evaluation of the morphological changes of gastric mucosa induced by a low concentration of acetic acid using a rat model.

    Science.gov (United States)

    Nakao, Ken-ichiro; Ro, Ayako; Kibayashi, Kazuhiko

    2014-02-01

    Oral ingestion of concentrated acetic acid causes corrosive injury of the gastrointestinal tract. To assess the effects of a low concentration of acetic acid on gastric mucosa, we examined the gastric mucosal changes in rats at 1 and 3 days after the injection of 5% or 25% acetic acid into the gastric lumen. The area of the gastric ulcerative lesions in the 25% acetic acid group was significantly larger than that in the 5% acetic acid group. The lesion area was reduced significantly at 3 days after injection in the 5% acetic acid group, whereas no significant difference in lesion area was observed at 1 and 3 days in the 25% acetic acid group. Histologically, corrosive necrosis was limited to the mucosal layer in the 5% acetic acid group, whereas necrosis extended throughout the gastric wall in the 25% acetic acid group. At 3 days post-injection, the 25% acetic acid group showed widespread persistent inflammation, whereas the 5% acetic acid group showed widespread appearance of fibroblasts indicative of a healing process. These results indicate that a low concentration of acetic acid damages the gastric mucosa and that the degree of mucosal damage depends on the concentration of acetic acid.

  16. 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.

  17. The Healing Effect of Hydroalcoholic Extract of Hypericum Perforatum on Acetic Acid-Induced Ulcerative Colitis in Male Rats

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    Nader Tanideh

    2017-02-01

    Full Text Available Background & Objective: Anti-inflammatory effect of Hypericum have long been considered. Ulcerative Colitis (UC is a form of Inflammatory Bowel Disease (IBD. In this study, the effects of Hypericum perforatum on histopathological changes and tissue malondialdehyde (MDA level of colonic tissue in rats with induced UC were evaluated. Materials & Methods: 70 rats were divided into seven equal groups. Colitis was induced by acetic acid.. Groups I and II received 1 mL of 600 and 300 mg/kg H. perforatum extract orally per day respectively; groups III and IV received 1 mL of 20% and 10% intra-colonic gel form of H. perforatum extract daily respectively; group V, as positive control, received 1 mL of intra-colonic Asacol; group VI received 1 mL of normal saline as negative control; group VII received just intra-colonic gel base. All the animals were evaluated for histological changes and tissue MDA level of colon seven days after the treatment. Results: H. perforatum extract in the two forms of trans-rectal and oral administration could result in a more healing effect on acetic acid-induced damaged colonic tissue with a reduction in the MDA activity. In trans-rectal administration, the 20% gel had a better healing response than the 10% gel. In oral administration, the 600 mg/kg dosage had a better healing response than the 300 mg/kg. Conclusions: Therefor, H. perforatum can be considered as a treatment of choice for UC especially in trans-rectal gel form.

  18. RNA-Seq-based transcriptomic and metabolomic analysis reveal stress responses and programmed cell death induced by acetic acid in Saccharomyces cerevisiae

    Science.gov (United States)

    Dong, Yachen; Hu, Jingjin; Fan, Linlin; Chen, Qihe

    2017-01-01

    As a typical harmful inhibitor in cellulosic hydrolyzates, acetic acid not only hinders bioethanol production, but also induces cell death in Saccharomyces cerevisiae. Herein, we conducted both transcriptomic and metabolomic analyses to investigate the global responses under acetic acid stress at different stages. There were 295 up-regulated and 427 down-regulated genes identified at more than two time points during acetic acid treatment (150 mM, pH 3.0). These differentially expressed genes (DEGs) were mainly involved in intracellular homeostasis, central metabolic pathway, transcription regulation, protein folding and stabilization, ubiquitin-dependent protein catabolic process, vesicle-mediated transport, protein synthesis, MAPK signaling pathways, cell cycle, programmed cell death, etc. The interaction network of all identified DEGs was constructed to speculate the potential regulatory genes and dominant pathways in response to acetic acid. The transcriptional changes were confirmed by metabolic profiles and phenotypic analysis. Acetic acid resulted in severe acidification in both cytosol and mitochondria, which was different from the effect of extracellular pH. Additionally, the imbalance of intracellular acetylation was shown to aggravate cell death under this stress. Overall, this work provides a novel and comprehensive understanding of stress responses and programmed cell death induced by acetic acid in yeast. PMID:28209995

  19. EGFR-p38 MAPK信号通路参与机械通气肺损伤大鼠肺组织HMGB1的表达%EGFR-p38 MAPK signaling pathway is involved in expression of HMGB1 in pulmonary tissues of rats with ventilator-induced lung injury

    Institute of Scientific and Technical Information of China (English)

    唐春林; 丁宁; 程傲冰

    2013-01-01

    AIM:To investigate the role of epidermal growth factor receptor (EGFR)-p38 mitogen-activated protein kinase (MAPK) pathway in the expression of high mobility group box 1 protein (HMGB1) in the lung tissues of rats with ventilator-induced lung injury (VILI).METHODS:Thirty-two healthy Sprague-Dawley (SD) rats were randomly divided into 4 groups (n =8 each):group A,spontaneous breathing; group B,small tidal volume ventilation (VT =8 mL/ kg) ; group C,high tidal volume ventilation (VT =40 mL/kg) ; group D,high tidal volume ventilation plus EGFR antagonist AG-1478.The rats in group B,group C and group D were mechanically ventilated for 4 h and then all animals were sacrificed.Total protein content and white blood cell (WBC) count in bronchoalveolar lavage fluid (BALF),the lung wet/ dry weight ratio (W/D) and myeloperoxidase (MPO) activity were determined.The histological changes of lung tissues were observed by HE staining.The EGFR protein and mRNA expression,p38 MAPK activity and HMGB1 protein expression in the lung tissues were also detected.RESULTS:The inflammatory responses as evidenced by lung HE staining,total protein and WBC in BALF,the lung W/D and MPO activity were significantly higher in group C than those in group A (P < 0.05).The mRNA expression of EGFR,EGFR activity,p38 activity and HMGB1 protein level also significantly increased in group C (P < 0.05) as compared with group A.Significant decreases in the above indexes in group D were observed as compared with group C.CONCLUSION:High tidal volume ventilation induces acute lung injury,which may be related to up-regulation of HMGB1 expression through EGFR-p38 MAPK signal pathway.%目的:研究表皮生长因子受体(epidermal growth factor receptor,EGFR)-p38丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)信号通路在机械通气肺损伤(ventilator-induced lung injury,VILI)大鼠肺组织高迁移率族盒蛋白1(high mobility group box 1 protein,HMGB1)表达

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

    Energy Technology Data Exchange (ETDEWEB)

    Faria, Jerusa A.Q.A.; Andrade, Carolina de; Goes, Alfredo M. [Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, Belo Horizonte, MG, 31270-901 (Brazil); Rodrigues, Michele A. [Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, Belo Horizonte, MG, 31270-901 (Brazil); Department of General Pathology, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, Belo Horizonte, MG, 31270-901 (Brazil); Gomes, Dawidson A., E-mail: dawidson@ufmg.br [Department of Biochemistry and Immunology, Universidade Federal de Minas Gerais, Av. Antonio Carlos, 6627, Belo Horizonte, MG, 31270-901 (Brazil)

    2016-09-09

    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. - Highlights: • EGF, HB-EGF, TGF-α, β-Cellulin are involved in the EGFR nuclear translocation. • Amphiregulin and epiregulin did not promote nuclear translocation of EGFR. • EGF, HB-EGF, TGF-α and β-Cellulin have a role in SkHep-1 cells migration. • EGFR ligands associated with better prognosis don't stimulate EGFR translocation.

  1. Mechanosensitive neurons on the internal reproductive tract contribute to egg-laying-induced acetic acid attraction in Drosophila.

    Science.gov (United States)

    Gou, Bin; Liu, Ying; Guntur, Ananya R; Stern, Ulrich; Yang, Chung-Hui

    2014-10-23

    Selecting a suitable site to deposit their eggs is an important reproductive need of Drosophila females. Although their choosiness toward egg-laying sites is well documented, the specific neural mechanism that activates females' search for attractive egg-laying sites is not known. Here, we show that distention and contraction of females' internal reproductive tract triggered by egg delivery through the tract plays a critical role in activating such search. We found that females start to exhibit acetic acid (AA) attraction prior to depositing each egg but no attraction when they are not laying eggs. Artificially distending the reproductive tract triggers AA attraction in non-egg-laying females, whereas silencing the mechanosensitive neurons we identified that can sense the contractile status of the tract eliminates such attraction. Our work uncovers the circuit basis of an important reproductive need of Drosophila females and provides a simple model for dissecting the neural mechanism that underlies a reproductive need-induced behavioral modification.

  2. Investigation of Sesamol on Myeloperoxidase and Colon Morphology in Acetic Acid-Induced Inflammatory Bowel Disorder in Albino Rats

    Directory of Open Access Journals (Sweden)

    Phani Krishna Kondamudi

    2014-01-01

    Full Text Available Background. Inflammatory bowel disease (IBD is a chronic inflammatory disorder of gastrointestinal tract of immune, genetic, and environmental origin. In the present study, we examined the effects of sesamol (SES, which is the active constituent of sesame oil in the acetic acid (AA induced model for IBD in rats. Methods. The groups were divided into normal control, AA control, SES, and sulfasalazine (SS. On day 7, the rats were killed, colon was removed, and the macroscopic, biochemical, and histopathological evaluations were performed. Results. The levels of MPO, TBARS, and tissue nitrite increased significantly (P<0.05 in the AA group whereas they reduced significantly in the SES and SS treated groups. Serum nitrite levels were found to be insignificant between the different groups. Conclusions. The mucosal protective effects of sesamol in IBD are due to its potential to reduce the myeloperoxidase and nitrite content.

  3. Antiamnesic effects of ethyl acetate fraction from chestnut (Castanea crenata var. dulcis) inner skin on Aβ(25-35)-induced cognitive deficits in mice.

    Science.gov (United States)

    Jeong, Hee-Rok; Jo, Yu Na; Jeong, Ji Hee; Jin, Dong Eun; Song, Byung Gi; Choi, Soo Jung; Shin, Dong-Hoon; Heo, Ho Jin

    2012-12-01

    To investigate neuronal cell protective effects of an ethyl acetate fraction from chestnut inner skin, in vitro assays, including 2',7'-dichlorofluorescein diacetate, 3-[4,5-dimethythiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT), and lactate dehydrogenase (LDH), were performed. Intracellular accumulation of reactive oxygen species resulting from hydrogen peroxide (H(2)O(2)) treatment of PC12 cells was significantly reduced when ethyl acetate fractions were present in the medium compared to PC12 cells treated with H(2)O(2) only. In a cell viability assay using MTT, the ethyl acetate fraction protected against H(2)O(2)-induced neurotoxicity, and inhibited LDH release into the medium. In addition, the ethyl acetate fraction improved in vivo cognitive ability against amyloid β-peptide (Aβ)-induced neuronal deficit. High-performance liquid chromatography analyses showed that gallic acid, catechin, and epicatechin were predominant phenolics in the ethyl acetate fraction. Consequently, the results suggest that chestnut inner skin, including above phenolics, could ameliorate Aβ-induced learning and memory deficiency, and be utilized as effective substances for neurodegenerative disorders, notably Alzheimer's disease.

  4. 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.

  5. 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.

  6. 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.

  7. ERK2-Pyruvate Kinase Axis Permits Phorbol 12-Myristate 13-Acetate-induced Megakaryocyte Differentiation in K562 Cells.

    Science.gov (United States)

    Chaman, Noor; Iqbal, Mohammad Askandar; Siddiqui, Farid Ahmad; Gopinath, Prakasam; Bamezai, Rameshwar N K

    2015-09-25

    Metabolic changes that contribute to differentiation are not well understood. Overwhelming evidence shows the critical role of glycolytic enzyme pyruvate kinase (PK) in directing metabolism of proliferating cells. However, its role in metabolism of differentiating cells is unclear. Here we studied the role of PK in phorbol 12-myristate 13-acetate (PMA)-induced megakaryocytic differentiation in human leukemia K562 cells. We observed that PMA treatment decreased cancer-type anabolic metabolism but increased ATP production, along with up-regulated expression of two PK isoforms (PKM2 and PKR) in an ERK2-dependent manner. Interestingly, silencing of PK (PKM2 and PKR) inhibited PMA-induced megakaryocytic differentiation, as revealed by decreased expression of megakaryocytic differentiation marker CD61 and cell cycle behavior. Further, PMA-induced ATP production reduced greatly upon PK silencing, suggesting that PK is required for ATP synthesis. In addition to metabolic effects, PMA treatment also translocated PKM2, but not PKR, into nucleus. ERK1/2 knockdowns independently and together suggested the role of ERK2 in the up-regulation of both the isoforms of PK, proposing a role of ERK2-PK isoform axis in differentiation. Collectively, our findings unravel ERK2 guided PK-dependent metabolic changes during PMA induction, which are important in megakaryocytic differentiation.

  8. ERK2-Pyruvate Kinase Axis Permits Phorbol 12-Myristate 13-Acetate-induced Megakaryocyte Differentiation in K562 Cells*

    Science.gov (United States)

    Chaman, Noor; Iqbal, Mohammad Askandar; Siddiqui, Farid Ahmad; Gopinath, Prakasam; Bamezai, Rameshwar N. K.

    2015-01-01

    Metabolic changes that contribute to differentiation are not well understood. Overwhelming evidence shows the critical role of glycolytic enzyme pyruvate kinase (PK) in directing metabolism of proliferating cells. However, its role in metabolism of differentiating cells is unclear. Here we studied the role of PK in phorbol 12-myristate 13-acetate (PMA)-induced megakaryocytic differentiation in human leukemia K562 cells. We observed that PMA treatment decreased cancer-type anabolic metabolism but increased ATP production, along with up-regulated expression of two PK isoforms (PKM2 and PKR) in an ERK2-dependent manner. Interestingly, silencing of PK (PKM2 and PKR) inhibited PMA-induced megakaryocytic differentiation, as revealed by decreased expression of megakaryocytic differentiation marker CD61 and cell cycle behavior. Further, PMA-induced ATP production reduced greatly upon PK silencing, suggesting that PK is required for ATP synthesis. In addition to metabolic effects, PMA treatment also translocated PKM2, but not PKR, into nucleus. ERK1/2 knockdowns independently and together suggested the role of ERK2 in the up-regulation of both the isoforms of PK, proposing a role of ERK2-PK isoform axis in differentiation. Collectively, our findings unravel ERK2 guided PK-dependent metabolic changes during PMA induction, which are important in megakaryocytic differentiation. PMID:26269597

  9. 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

  10. EGFR-TKI resistance due to BIM polymorphism can be circumvented in combination with HDAC inhibition.

    Science.gov (United States)

    Nakagawa, Takayuki; Takeuchi, Shinji; Yamada, Tadaaki; Ebi, Hiromichi; Sano, Takako; Nanjo, Shigeki; Ishikawa, Daisuke; Sato, Mitsuo; Hasegawa, Yoshinori; Sekido, Yoshitaka; Yano, Seiji

    2013-04-15

    BIM (BCL2L11) is a BH3-only proapoptotic member of the Bcl-2 protein family. BIM upregulation is required for apoptosis induction by EGF receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKI) in EGFR-mutant forms of non-small cell lung cancer (NSCLC). Notably, a BIM deletion polymorphism occurs naturally in 12.9% of East Asian individuals, impairing the generation of the proapoptotic isoform required for the EGFR-TKIs gefitinib and erlotinib and therefore conferring an inherent drug-resistant phenotype. Indeed, patients with NSCLC, who harbored this host BIM polymorphism, exhibited significantly inferior responses to EGFR-TKI treatment than individuals lacking this polymorphism. In an attempt to correct this response defect in the resistant group, we investigated whether the histone deacetylase (HDAC) inhibitor vorinostat could circumvent EGFR-TKI resistance in EGFR-mutant NSCLC cell lines that also harbored the BIM polymorphism. Consistent with our clinical observations, we found that such cells were much less sensitive to gefitinib-induced apoptosis than EGFR-mutant cells, which did not harbor the polymorphism. Notably, vorinostat increased expression in a dose-dependent manner of the proapoptotic BH3 domain-containing isoform of BIM, which was sufficient to restore gefitinib death sensitivity in the EGFR mutant, EGFR-TKI-resistant cells. In xenograft models, while gefitinib induced marked regression via apoptosis of tumors without the BIM polymorphism, its combination with vorinostat was needed to induce marked regression of tumors with the BIM polymorphism in the same manner. Together, our results show how HDAC inhibition can epigenetically restore BIM function and death sensitivity of EGFR-TKI in cases of EGFR-mutant NSCLC where resistance to EGFR-TKI is associated with a common BIM polymorphism.

  11. 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...... (RTK) EphA2. EphA2 belongs to the large Eph-receptor family, which has mainly been associated with neuronal development. More recently, expression of several Eph-receptors has been detected in many different cancer types. Elevated EphA2 expression has been reported in a broad range of human cancer...... in tumor metastasis and angiogenesis. The aim of the PhD-project was to study the EGFR-induced EphA2 expression in mammalian cancer cells, and to evaluate the role of EphA2 expression on EGFR regulated cell signaling and functional effects using different in vitro models. The results have shown that ligand...

  12. Deubiquitination of EGFR by Cezanne-1 contributes to cancer progression

    Science.gov (United States)

    Pareja, Fresia; Ferraro, Daniela Aleida; Rubin, Chanan; Cohen-Dvashi, Hadas; Zhang, Fan; Aulmann, Sebastian; Ben-Chetrit, Nir; Pines, Gur; Navon, Roy; Crosetto, Nicola; Köstler, Wolfgang; Carvalho, Silvia; Lavi, Sara; Schmitt, Fernando; Dikic, Ivan; Yakhini, Zohar; Sinn, Peter; Mills, Gordon B.; Yarden, Yosef

    2011-01-01

    Once stimulated, the epidermal growth factor receptor (EGFR) undergoes self-phosphorylation, which, on the one hand, instigates signaling cascades, and on the other hand, recruits CBL ubiquitin ligases, which mark EGFRs for degradation. Using RNA interference screens, we identified a deubiquitinating enzyme, Cezanne-1, that opposes receptor degradation and enhances EGFR signaling. These functions require the catalytic and ubiquitin-binding domains of Cezanne-1, and they involve physical interactions and trans-phosphorylaton of Cezanne-1 by EGFR. In line with the ability of Cezanne-1 to augment EGF-induced growth and migration signals, the enzyme is overexpressed in breast cancer. Congruently, the corresponding gene is amplified in approximately one third of mammary tumors, and high transcript levels predict an aggressive disease course. In conclusion, deubiquitination by Cezanne-1 curtails degradation of growth factor receptors, thereby promotes oncogenic growth signals. PMID:22179831

  13. 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....

  14. Effect of Coriandrum sativum hydroalcoholic extract and its essential oil on acetic acid- induced acute colitis in rats

    Directory of Open Access Journals (Sweden)

    Bahareh Heidari

    2016-03-01

    Full Text Available Objective: The aim of this study was to determine the protective effects of Coriandrum sativum on acetic acid-inducedcolitis in rats. C. sativum (Coriander has long been used in Iranian traditional medicine and its use as an anti-inflammatory agent is still common in some herbal formulations.  Materials and Methods: Colitis was induced by intra-rectal administration of 2ml acetic acid 4% in fasted male Wistar rats. Treatment was carried out using three increasing doses of extract (250, 500, 1000 mg/kg and essential oil (0.25, 0.5, 1 ml/kg of coriander started 2 h before colitis induction and continued for a five-day period. Colon biopsies were taken for weighting, macroscopic scoring of injured tissue, histopathological examination and measuring myeloperoxidase (MPO activity.  Results: Colon weight was decreased in the groups treated with extract (500 and 1000 mg/kg and essential oil (0.5 ml/kg compared to the control group. Regarding MPO levels, ulcer severity and area as well as the total colitis index, same results indicating meaningful alleviation of colitis was achieved after treatment with oral extract and essential oil.  Conclusion: Since the present experiment was made by oral fractions of coriander thus the resulting effects could be due to both the absorption of the active ingredients and/or the effect of non-absorbable materials on colitis after reaching the colon. In this regard, we propose more toxicological and clinical experiments to warranty its beneficial application in human inflammatory bowel diseases.

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

    Science.gov (United States)

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

    2014-01-01

    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 modulation of serum alkaline phosphatase, lactate dehydrogenase, superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA) and myeloperoxidase (MPO) content along with colonic nitric oxide (NO), xanthine oxidase (XO) level and protein carbonyl content in the colonic tissue as well as in blood. Naringin (40 and 80 mg/kg) exerted a dose dependent (P < 0.05) ameliorative effect, as it significantly increased hematological parameter as well as colonic SOD and GSH. There was a significant (P < 0.05) and dose dependant inhibition of macroscopical score, ulcer area along with colonic MDA, MPO activity by the 7 days of pretreatment of naringin (40 and 80 mg/kg). Biochemical studies revealed a significant (P < 0.05) dose dependant inhibition in serum alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) levels by pretreatment of naringin. Increased levels of colonic NO, XO, protein carbonyl content and DNA damage were also significantly decreased by naringin pretreatment. The findings of the present investigation propose that naringin has an anti-inflammatory, anti-oxidant and anti-apoptotic potential effect at colorectal sites as it modulates the production and expression of oxidative mediators such as MDA, MPO, NO and XO, thus reducing DNA damage. PMID:24683411

  17. 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

  18. An ethyl acetate fraction of Moringa oleifera Lam. Inhibits human macrophage cytokine production induced by cigarette smoke.

    Science.gov (United States)

    Kooltheat, Nateelak; Sranujit, Rungnapa Pankla; Chumark, Pilaipark; Potup, Pachuen; Laytragoon-Lewin, Nongnit; Usuwanthim, Kanchana

    2014-02-18

    Moringa oleifera Lam. (MO) has been reported to harbor anti-oxidation and anti-inflammatory activity and useful in the treatment of inflammatory diseases. However, despite these findings there has been little work done on the effects of MO on immune cellular function. Since macrophages, TNF and related cytokines play an important pathophysiologic role in lung damage induced by cigarette smoke, we examined the effects of MO on cigarette smoke extract (CSE)-induced cytokine production by human macrophages. An ethyl acetate fraction of MO (MOEF) was prepared from fresh leaves extract of Moringa and shown to consist of high levels of phenolic and antioxidant activities. Human monocyte derived macrophages (MDM) pre-treated with varying concentrations of MOEF showed decreased production of TNF, IL-6 and IL-8 in response to both LPS and CSE. The decrease was evident at both cytokine protein and mRNA levels. Furthermore, the extract inhibited the expression of RelA, a gene implicated in the NF-κB p65 signaling in inflammation. The findings highlight the ability of MOEF to inhibit cytokines (IL-8) which promote the infiltration of neutrophils into the lungs and others (TNF, IL-6) which mediate tissue disease and damage.

  19. An Ethyl Acetate Fraction of Moringa oleifera Lam. Inhibits Human Macrophage Cytokine Production Induced by Cigarette Smoke

    Directory of Open Access Journals (Sweden)

    Nateelak Kooltheat

    2014-02-01

    Full Text Available Moringa oleifera Lam. (MO has been reported to harbor anti-oxidation and anti-inflammatory activity and useful in the treatment of inflammatory diseases. However, despite these findings there has been little work done on the effects of MO on immune cellular function. Since macrophages, TNF and related cytokines play an important pathophysiologic role in lung damage induced by cigarette smoke, we examined the effects of MO on cigarette smoke extract (CSE—induced cytokine production by human macrophages. An ethyl acetate fraction of MO (MOEF was prepared from fresh leaves extract of Moringa and shown to consist of high levels of phenolic and antioxidant activities. Human monocyte derived macrophages (MDM pre-treated with varying concentrations of MOEF showed decreased production of TNF, IL-6 and IL-8 in response to both LPS and CSE. The decrease was evident at both cytokine protein and mRNA levels. Furthermore, the extract inhibited the expression of RelA, a gene implicated in the NF-κB p65 signaling in inflammation. The findings highlight the ability of MOEF to inhibit cytokines (IL-8 which promote the infiltration of neutrophils into the lungs and others (TNF, IL-6 which mediate tissue disease and damage.

  20. Ethyl acetate extract of Peperomia tetraphylla induces cytotoxicity, cell cycle arrest, and apoptosis in lymphoma U937 cells.

    Science.gov (United States)

    Yu, Dayong; Yang, Xiuxiu; Lu, Xuan; Shi, Liying; Feng, Baomin

    2016-12-01

    The current study evaluated the cytotoxicity and the mechanism of apoptotic induction by Peperomia tetraphylla in U937 lymphoma cells. The results showed that P. tetraphylla ethyl acetate extract (EAEPT) inhibited the cell growth in U937 cells by MTT assay. After the U937 cells were treated with EAEPT, the cells exhibited marked morphological features of apoptosis (Hoechst 33342 staining) and the number of apoptotic cell (Annexin V-FITC/PI staining) increased. The treatment of EAEPT could induce loss of mitochondrial membrane potential (MMP) and increase the ROS level. Moreover, EAEPT treatment resulted in the accumulation of cells at S phase. We found that EAEPT could induce the cleavage of the caspase 3, caspase 8, caspase 9 and Bid. And the treatment of EAEPT could increase expression of Bax and down-regulate the expression of CCNB1, CCND1 and CDK1. The sub-fraction of EAEPT, namely EASub1 demonstrated the highest cytotoxicity activity on U937 cells. It was confirmed that EAEPT could inhibit the growth of U937 cells by blocking the cell cycle and prompted apoptosis via the ROS-medicated mitochondria pathway in vitro.

  1. 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.

  2. Synthesis of ZnO nanocoatings by decomposition of zinc acetate induced by electrons emitted by indium

    Science.gov (United States)

    Svoboda, Ladislav; Dvorský, Richard; Praus, Petr; Matýsek, Dalibor; Bednář, Jiří

    2016-12-01

    In this work, a new method for the synthesis of ZnO nanocoatings is presented. It was tested for the nanocoating of silica nanoparticles forming core/shell SiO2/ZnO nanoparticles by the decomposition of zinc acetate in silica aqueous nanodispersions induced by electrons generated by a plate indium photocathode, which was irradiated with a UV Hg lamp with maximum intensity at the wavelength of 245 nm. The ZnO nanocoatings were examined by X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (DRS), photoluminescence spectroscopy (PLS), dynamic light scattering (DLS) and transmission electron microscopy (TEM). It was found that ZnO of hexagonal structure formed nanocoatings with the mean thickness of 13 nm. The photocatalytic activity of ZnO nanocoatings was verified by the photocatalytic decomposition of methylene blue (MB). Such nanocoating procedure based on the electron-induced decomposition of suitable metal salts could be a promising method for various applications in nanotechnology.

  3. Evaluation of the protective effect of Pterocarpus marsupium on acetic acid-induced ulcerative colitis in rats.

    Science.gov (United States)

    Mathew, Merin Maria; Han, Nguyen Vinh; Murugesan, A; Raj, E Arun; Prasanth, K G

    2015-08-01

    The aim of the study was to evaluate the effect of Pterocarpus marsupium (PM) on acetic acid (AA)-induced ulcerative colitis (UC) in rats. The rats were divided into five groups, each having six rats. PM extract 100 mg and 200 mg/kg was given orally to groups four and five, respectively, and standard drug sulfasalazine (100 mg/kg, p.o) to group three. Group two served as UC control animals, and group one control animals received vehicle for 7 days. UC was induced by administering AA (3 % v/v of 2 ml) to all the animals except group one. After 72 h, the animals were killed and the colon was dissected out for microscopic, clinical evaluation, histopathological study and biochemical estimation. PM (100 and 200 mg/kg)-treated group had significantly reduced colon inflammation and mucosal damage. The treatment also normalized the altered antioxidant enzyme levels (LPO, SOD and GSH). Histopathological studies support the effect. The protective effect of PM may be due to antiinflammatory and antioxidant properties.

  4. Intracerebroventricular infusion of the (Pro)renin receptor antagonist PRO20 attenuates deoxycorticosterone acetate-salt-induced hypertension.

    Science.gov (United States)

    Li, Wencheng; Sullivan, Michelle N; Zhang, Sheng; Worker, Caleb J; Xiong, Zhenggang; Speth, Robert C; Feng, Yumei

    2015-02-01

    We previously reported that binding of prorenin to the (pro)renin receptor (PRR) plays a major role in brain angiotensin II formation and the development of deoxycorticosterone acetate (DOCA)-salt hypertension. Here, we designed and developed an antagonistic peptide, PRO20, to block prorenin binding to the PRR. Fluorescently labeled PRO20 bound to both mouse and human brain tissues with dissociation constants of 4.4 and 1.8 nmol/L, respectively. This binding was blocked by coincubation with prorenin and was diminished in brains of neuron-specific PRR-knockout mice, indicating specificity of PRO20 for PRR. In cultured human neuroblastoma cells, PRO20 blocked prorenin-induced calcium influx in a concentration- and AT(1) receptor-dependent manner. Intracerebroventricular infusion of PRO20 dose-dependently inhibited prorenin-induced hypertension in C57Bl6/J mice. Furthermore, acute intracerebroventricular infusion of PRO20 reduced blood pressure in both DOCA-salt and genetically hypertensive mice. Chronic intracerebroventricular infusion of PRO20 attenuated the development of hypertension and the increase in brain hypothalamic angiotensin II levels induced by DOCA-salt. In addition, chronic intracerebroventricular infusion of PRO20 improved autonomic function and spontaneous baroreflex sensitivity in mice treated with DOCA-salt. In summary, PRO20 binds to both mouse and human PRRs and decreases angiotensin II formation and hypertension induced by either prorenin or DOCA-salt. Our findings highlight the value of the novel PRR antagonist, PRO20, as a lead compound for a novel class of antihypertensive agents and as a research tool to establish the validity of brain PRR antagonism as a strategy for treating hypertension. © 2014 American Heart Association, Inc.

  5. Mixed lineage kinase 3 inhibits phorbol myristoyl acetate-induced DNA synthesis but not osteopontin expression in rat mesangial cells.

    Science.gov (United States)

    Parameswaran, Narayanan; Hall, Carolyn S; Bock, Barbara C; Sparks, Harvey V; Gallo, Kathleen A; Spielman, William S

    2002-12-01

    Mixed lineage kinase 3 (MLK 3) (also called SPRK or PTK-1) is a recently described member of the family of the mixed lineage kinase subfamily of Ser/Thr protein kinases that interacts with mitogen-activated protein kinase pathways. In order to test the biological relevance and potential interaction of MLK 3 with protein kinase C-mediated signaling pathways, human MLK 3 was stably expressed in rat glomerular mesangial cells using a retroviral vector (LXSN) and the effects of phorbol myristoyl acetate (PMA) on DNA synthesis and osteopontin mRNA expression were examined. In control (vector-transfected) mesangial cells PMA increased [3H]-thymidine incorporation in a concentration-dependent manner. In mesangial cells stably expressing MLK 3, the PMA-induced increase in [3H]-thymidine incorporation was significantly reduced (> 50%). However, the PMA-induced increase in osteopontin mRNA was not affected by MLK 3 expression. To determine the mechanisms of these effects, activation of ERK2, JNK1 and p38 in response to PMA was examined in both vector and MLK 3 transfected cells. ERK2 activation was increased several fold by PMA in control cells but was attenuated significantly in MLK 3 expressing cells, suggesting that MLK 3 expression in mesangial cells can negatively regulate the ERK pathway. PMA had no significant effect on JNK and P38 activation, in either vector- or MLK 3-expressing cells. PD98059, a MEK inhibitor blocked PMA-induced DNA synthesis without affecting osteopontin expression. These results suggest that while protein kinase C activation increases cellular proliferation and osteopontin mRNA expression, over-expression of MLK 3 affects only the PKC-induced DNA synthesis, probably through inhibition of ERK. These results also indicate a novel mechanism of growth regulation by a member of the mixed-lineage kinase family that might have significant therapeutic implications in proliferative glomerulonephritis.

  6. Protective Role of Omega-3 Polyunsaturated Fatty Acid against Lead Acetate-Induced Toxicity in Liver and Kidney of Female Rats

    OpenAIRE

    Abdou, Heba M.; Mohamed A. Hassan

    2014-01-01

    The present study was conducted to investigate the protective role of Omega-3 polyunsaturated fatty acids against lead acetate-induced toxicity in liver and kidney of female rats. Animals were divided into four equal groups; group 1 served as control while groups 2 and 3 were treated orally with Omega-3 fatty acids at doses of 125 and 260 mg/kg body weight, respectively, for 10 days. These groups were also injected with lead acetate (25 mg/kg body weight) during the last 5 days. Group 4 was t...

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

    Science.gov (United States)

    D’Ambrosio, Steven M.; Han, Chunhua; Pan, Li; Kinghorn, A. Douglas; Ding, Haiming

    2011-01-01

    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. Compound 1 and 2 both inhibited phosphorylation of c-RAF (Ser338) and ERK1/2 (Thr202/Tyr204). Compound 2, but not compound 1, prevented EGF-induced activation of EGFR (Tyr1173). When compounds 1 and 2 were combined they synergistically inhibited c-RAF (Ser338) and ERK1/2 (Thr202/Tyr204) phosphorylation, and human oral cancer cell proliferation. The present data suggest that the potential anticancer activity of avocado fruits is due to a combination of specific aliphatic acetogenins that target two key components of the EGFR/RAS/RAF/MEK/ERK1/2 cancer pathway. PMID:21596018

  8. The effect of intracerebroventricular injection of histamine in visceral nociception induced by acetic acid in rats

    OpenAIRE

    Zanboori Ali; Tamaddonfard Esmaeal; Mojtahedin Ali

    2010-01-01

    Objective : This study was designed to investigate the role of brain histamine and H1 and H2 receptors in mediating the central perception of visceral pain in rats. Materials and Methods : In conscious rats implanted with a lateral brain ventricle cannula, the effect of intracerebroventricular (i.c.v.) injection of histamine (2.5, 10, and 40 μg), and chlorpheniramine and ranitidine at the same doses of 5, 20, and 80 μg were investigated on visceral pain. Visceral nociception induce...

  9. Isatinphenylsemicarbazones as efficient colorimetric sensors for fluoride and acetate anions - anions induce tautomerism.

    Science.gov (United States)

    Jakusová, Klaudia; Donovalová, Jana; Cigáň, Marek; Gáplovský, Martin; Garaj, Vladimír; Gáplovský, Anton

    2014-04-05

    The anion induced tautomerism of isatin-3-4-phenyl(semicarbazone) derivatives is studied herein. The interaction of F(-), AcO(-), H2PO4(-), Br(-) or HSO4(-) anions with E and Z isomers of isatin-3-4-phenyl(semicarbazone) and N-methylisatin-3-4-phenyl(semicarbazone) as sensors influences the tautomeric equilibrium of these sensors in the liquid phase. This tautomeric equilibrium is affected by (1) the inter- and intra-molecular interactions' modulation of isatinphenylsemicarbazone molecules due to the anion induced change in the solvation shell of receptor molecules and (2) the sensor-anion interaction with the urea hydrogens. The acid-base properties of anions and the difference in sensor structure influence the equilibrium ratio of the individual tautomeric forms. Here, the tautomeric equilibrium changes were indicated by "naked-eye" experiment, UV-VIS spectral and (1)H NMR titration, resulting in confirmation that appropriate selection of experimental conditions leads to a high degree of sensor selectivity for some investigated anions. Sensors' E and Z isomers differ in sensitivity, selectivity and sensing mechanism. Detection of F(-) or CH3COO(-) anions at high weakly basic anions' excess is possible.

  10. 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.

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

    Directory of Open Access Journals (Sweden)

    S.E.D.C. Jorge

    2014-11-01

    Full Text Available 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.

  12. 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 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.

  13. Hydroalcoholic extract of Brazilian red propolis exerts protective effects on acetic acid-induced ulcerative colitis in a rodent model.

    Science.gov (United States)

    Barbosa Bezerra, Gislaine; de Menezes de Souza, Luana; Dos Santos, Adailma Santana; de Almeida, Grace Kelly Melo; Souza, Marília Trindade Santana; Santos, Sandra Lauton; Aparecido Camargo, Enilton; Dos Santos Lima, Bruno; de Souza Araújo, Adriano Antunes; Cardoso, Juliana Cordeiro; Gomes, Silvana Vieira Floresta; Gomes, Margarete Zanardo; de Albuquerque, Ricardo Luiz Cavalcanti

    2017-01-01

    Ulcerative colitis (UC) is a common intestinal inflammatory disease with an etiology that is not well understood. Although the anti-inflammatory and anti-oxidant effects of the hydroalcoholic extract of Brazilian red propolis (HERP) have been reported in various experimental models, its protective effect in models of UC have not been evaluated. The purpose of this study was to investigate the chemopreventive effect of hydroalcoholic extract of Brazilian red propolis (HERP) in acetic acid-induced colitis (AAIC) using a rodent model. The HERP was chemically characterised by HPLC/DAD analyses. Male rats were randomly assigned into four groups: sham, vehicle (with AAIC, treated with vehicle), P10 (with AAIC, treated with 10mg/kg HERP), and P100 (with AAIC, treated with 100mg/kg HERP). Treatments were performed for 7days, and colitis was induced on day seven. Animals were euthanized 24h after colitis induction and body weight, colon length, gross and histological scores, malondialdehyde (MDA) and myeloperoxidase (MPO) concentrations in colon tissue, and the immunohistochemical expression of inducible nitric oxide synthase (iNOS) were assessed. The major compounds found in HERP were liquiritigenin (68.8mg/g), formononetin (54.29mg/g), biochanin A (30.97mg/g), and daidzein (19.90mg/g). Rats treated with 10mg/kg HERP demonstrated significant decreases in MPO concentrations, gross and histological scores of tissue damage, and iNOS expression (p<0.05). Similarly, rats treated with 100mg/kg HERP demonstrated significant decreases in MPO levels (p<0.05) and histological scores of tissue damage (p<0.05). The results of this study indicate that oral administration of HERP attenuates AAIC in rats, which may be due to anti-inflammatory effects related to iNOS inhibition. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  14. Ethyl Acetate Extracts of Semen Impatientis Inhibit Proliferation and Induce Apoptosis of Human Prostate Cancer Cell Lines through AKT/ERK Pathways.

    Science.gov (United States)

    Wang, Tao; Cai, Yang; Song, Wen; Chen, Ruibao; Hu, Dunmei; Ye, Jianhan; Liu, Lu; Peng, Wei; Zhang, Junfeng; Wang, Shaogang; Yang, Weiming; Liu, Jihong; Ding, Yufeng

    2017-01-01

    Objective. To investigate the inhibitory effect of ethyl acetate extracts of Impatiens balsamina L. on prostate cancer cells. Methods. Impatiens balsamina L. was extracted to get water, ethanol, oil ether, ethyl acetate, and butanol extracts. CCK-8 assay was used to detect the inhibitory effect. Apoptosis rates and cell cycle distribution were detected by flow cytometry. Transwell assay was performed to test the ability of migration. The expressions of Bcl-2, Bax, cleaved-caspase-3, p-ERK, ERK, p-AKT, AKT, cyclin D1, cyclin E, and MMP2 were detected by Western blot. Results. Ethyl acetate extracts had the strongest inhibitory effect. After being treated with different concentrations of ethyl acetate extracts, the percentage of G0/G1 phase increased significantly, cyclin D1 and cyclin E expression decreased, apoptosis rate was significantly higher, and the ability of migration of PC-3 and RV1 was inhibited significantly. Western blot showed that the expressions of Bcl-2, p-ERK, and p-AKT were significantly decreased, but the expressions of Bax and caspase-3 cleavage were increased. Conclusions. Impatiens balsamina L. inhibited the proliferation of human prostate cancer cells; ethyl acetate extracts have the strongest effect. It could inhibit cell proliferation and migration, cause G1 phase arrest, and induce apoptosis probably through inhibition of the AKT and ERK pathways.

  15. 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.

  16. 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...

  17. 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.

  18. Isobolographic analysis of interaction between cyclooxygenase inhibitors and tramadol in acetic acid-induced writhing in mice.

    Science.gov (United States)

    Satyanarayana, Padi S V; Jain, Naveen K; Singh, Amarjit; Kulkarni, Shrinivas K

    2004-07-01

    Non-steroidal anti-inflammatory drugs (NSAIDs) and opioids are the most commonly used analgesics in the management of acute and chronic pain. Combined use of NSAIDs and opioids has been indicated for achieving better analgesia with reduced side effects. The present study was aimed at evaluating the combination of different NSAIDs, which inhibit cyclooxygenase (COX) enzymes and tramadol against acetic acid-induced writhing in mice. The expected beneficial effect of combination regimen was analyzed by isobolographic analysis. The oral and intrathecally administered tramadol, a mu-opioid and naproxen, a nonselective COX inhibitor produced dose-dependent antinociception, however, rofecoxib, a selective COX-2 inhibitor lacked analgesic efficacy in writhing test. Isobolographic analysis showed synergistic or supra-additive interactions for the combinations of naproxen and tramadol after oral and intrathecal administration. However, similar interaction was not observed when tramadol was combined with rofecoxib. Pretreatment with naloxone partially reversed the antinociceptive effect of tramadol per se and its combination with naproxen without modifying the per se effect of NSAID. The results demonstrated marked synergistic interaction between naproxen and tramadol and such interaction involved opioid as well as non-opioid mechanisms of tramadol and inhibition of COX-1 but not COX-2 by naproxen.

  19. Somatic pain sensitivity during formation and healing of acetic acid-induced gastric ulcers in conscious rats.

    Science.gov (United States)

    Yarushkina, Natalya; Bogdanov, Anatoly; Filaretova, Ludmila

    2006-06-30

    A classical feature of visceral pain is its referring to somatic locations. Gastric ulcer is a source of visceral pain. In the present study we investigated whether gastric ulcers may trigger the changes in somatic nociception. For this aim somatic pain sensitivity was estimated under conditions of gastric ulcer development and healing. Gastric ulcers were induced by luminal application of 60% acetic acid under surgical conditions. Control rats were subjected to the same surgical procedure, but with the application of saline instead of the acid. Somatic pain sensitivity (tail flick latency), plasma corticosterone level, adrenal and thymus weight were investigated under conditions of the formation and the healing of gastric ulcers. The application of the acid resulted in the formation of kissing gastric ulcers, the increase of somatic pain sensitivity (the decrease of tail flick latency) as well as the appearance of typical signs of chronic stress: long-lasting increase of plasma corticosterone level, adrenal gland hypertrophy and thymus gland involution. Natural healing of gastric ulcers was accompanied by restoration of pain sensitivity as well as attenuation of the signs of chronic stress. Delay of ulcer healing by the daily indomethacin administration (2 mg/kg, s.c.) prevented the restoration of somatic pain sensitivity. The results suggest that chronic gastric ulcers may trigger somatic hypersensitivity.

  20. Relationship between cross-linking conditions of ethylene vinyl acetate and potential induced degradation for crystalline silicon photovoltaic modules

    Science.gov (United States)

    Jonai, Sachiko; Hara, Kohjiro; Tsutsui, Yuji; Nakahama, Hidenari; Masuda, Atsushi

    2015-08-01

    In this study, we investigated the relationship in crystalline silicon (c-Si) photovoltaic (PV) modules between the cross-linking level of copolymer of ethylene and vinyl acetate (EVA) as the encapsulant and the degree of degradation due to potential induced degradation (PID) phenomenon. We used three methods for the determination of cross-linking level of EVA: xylene method, which is one of the solvent extraction methods (SEM), curing degree by differential scanning calorimetry (DSC), and viscoelastic properties by dynamic mechanical analysis (DMA). The results indicate that degradation of PV modules by PID test depends on the cross-linking level of EVA. The PV modules encapsulated by EVA with higher cross-linking level show lower degradation degree due to PID phenomenon. Also we showed that EVA with higher cross-linking level tended to be higher volume resistivity. This tendency is similar to that for electrical resistance value during the PID test. The PID test was also done by changing thickness of EVA between front cover glass and c-Si with the same cross-linking level. The PV modules encapsulated by thicker EVA between front cover glass and c-Si cell show lower degradation by PID. From these results, the PV modules encapsulated by EVA with higher cross-linking level, higher volume resistivity and increased thickness would be tolerant of PID phenomenon.

  1. 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.

  2. Mig6 Puts the Brakes on Mutant EGFR-Driven Lung Cancer | Center for Cancer Research

    Science.gov (United States)

    Lung cancer is the most common cause of cancer-related death worldwide. These cancers are often induced by mutations in the epidermal growth factor receptor (EGFR), resulting in constitutive activation of the protein’s tyrosine kinase domain. Lung cancers expressing these EGFR mutants are initially sensitive to tyrosine kinase inhibitors (TKIs), such as erlotinib, but often become resistant by developing compensatory mutations in EGFR or other growth-promoting pathways. To better understand how mutant EGFR initiates and maintains tumor growth in the hopes of identifying novel targets for drug development, Udayan Guha, M.D., Ph.D., of CCR’s Thoracic and Gastrointestinal Oncology Branch, and his colleagues examined the landscape of proteins phosphorylated in EGFR wild type and mutant cells. One protein hyper-phosphorylated in mutant EGFR cells was Mig6, a putative tumor suppressor.

  3. 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 ...

  4. Ginsenoside Rg3-induced EGFR/MAPK pathway deactivation inhibits melanoma cell proliferation by decreasing FUT4/LeY expression.

    Science.gov (United States)

    Shan, Xiu; Aziz, Faisal; Tian, Li Li; Wang, Xiao Qi; Yan, Qiu; Liu, Ji Wei

    2015-04-01

    Malignant melanoma is a destructive and lethal form of skin cancer with poor prognosis. An effective treatment for melanoma is greatly needed. Ginsenoside Rg3 is a herbal medicine with high antitumor activity. It is reported that abnormal glycosylation is correlated with the tumor cell growth. However, the antitumor effect of Rg3 on melanoma and its mechanism on regulating glycosylation are unknown. We found that Rg3 did not only inhibit A375 melanoma cell proliferation in a dose-dependent manner, but also decreased the expression of fucosyltransferase IV (FUT4) and its synthetic product Lewis Y (LeY), a tumor-associated carbohydrate antigen (TACA). Knocking down FUT4 expression by siRNA dramatically reduced FUT4/LeY level and inhibited cell proliferation through preventing the activation of EGFR/MAPK pathway. Consistently, the inhibitory effect of the Rg3 and FUT4 knockdown on melanoma growth was also seen in a xenograft melanoma mouse model. In conclusion, Rg3 effectively inhibited melanoma cell growth by downregulating FUT4 both in vitro and in vivo. Targeting FUT4/LeY mediated fucosylation by Rg3 inhibited the activation of EGFR/MAPK pathway and prevented melanoma growth. Results from this study suggest Rg3 is a potential novel therapy agent for melanoma treatment.

  5. Protective Role of Curcumin and Flunixin Against Acetic Acid-Induced Inflammatory Bowel Disease via Modulating Inflammatory Mediators and Cytokine Profile in Rats.

    Science.gov (United States)

    Gopu, Boobalan; Dileep, Rasakatla; Rani, Matukumalli Usha; Kumar, C S V Satish; Kumar, Matham Vijay; Reddy, Alla Gopala

    2015-01-01

    Ulcerative colitis is a chronically recurrent inflammatory bowel disease of unknown origin. The present study is to evaluate the effect of flunixin and curcumin in experimentally induced ulcerative colitis in rats. Animals were randomly divided into four groups, each consisting of 12 animals: normal control group, acetic acid group, curcumin-treated group, and flunixin-treated group. Induction of colitis by intracolonic administration of 4% acetic acid produced severe macroscopic inflammation in the colon, 14 days after acetic acid administration as assessed by the colonic damage score. Microscopically, colonic tissues showed ulceration, edema, and inflammatory cells infiltration. Biochemical studies revealed increased serum levels of lactate dehydrogenase (LDH), colonic alkaline phosphatase (ALP), and myeloperoxidase (MPO). Oxidative stress was indicated by elevated lipid peroxide formation and depleted reduced glutathione concentrations in colonic tissues. After induction of colitis, treatment with curcumin (50 mg/kg daily, p.o.) and flunixin (2.5 mg/kg daily, s.c.) decreased serum LDH, ALP, interleukin (IL)-1β, and tumor necrosis factor-α levels, as well as colonic MPO and lipid peroxide levels, whereas increased colonic prostaglandin E2 and IL-10 concentrations were observed. Moreover, effective doses of curcumin and flunixin were effective in restoring the histopathological changes induced by acetic acid administration. The findings of the present study provide evidence that flunixin may be beneficial in patients with inflammatory bowel disease.

  6. Augmentation of protein-derived acetic acid production by heat-alkaline-induced changes in protein structure and conformation.

    Science.gov (United States)

    Wang, Xu; Li, Yanbo; Liu, Junxin; Ren, Nan-Qi; Qu, Jiuhui

    2016-01-01

    Waste-derived acetic acid (HAc) is an attractive feedstock for microbe-mediated biofuel production. However, fermentative conversion of HAc from waste-activated sludge (WAS) has low yield because of the high concentration of proteins not readily utilizable by microorganisms without prior hydrolysis. We investigated a combined technology for HAc augmentation during sludge protein fermentation. The maximal HAc yield increased over two-fold, reaching 0.502 ± 0.021 g/g protein (0.36 ± 0.01 g COD/g COD, ∼52% of the total volatile fatty acids) when synthetic sludge protein was heated at 120 °C for 30 min, treated at pH 12 for 24 h, and fermented at pH 9 for 72 h. Comprehensive analysis illustrated that the heat-alkaline pretreatment significantly induced protein fragmentation, simultaneously increasing the efficiency of protein biohydrolysis (from 35.5% to 85.9%) by inducing conformational changes indicative of protein unfolding. Consequently, the native α-helix content was decreased from 67.3% to 32.5% by conversion to an unordered shape, whose content increased from 27.5% to 45.5%; disulfide bonds were cleaved, whereas the main S-S stretching pattern was altered from gauche-gauche-gauche to gauche-gauche-trans, consequently causing increased protein susceptibility to proteolytic hydrolysis (76.3% vs. 47.0%). Economic analysis indicated that anaerobic fermentation with appropriate heat-alkaline pretreatment is a cost-effective approach for waste conversion to energy sources such as HAc.

  7. L-arginine and aminoguanidine reduce colonic damage of acetic acid-induced colitis in rats: potential modulation of nuclear factor-κB/p65.

    Science.gov (United States)

    Farghaly, Hanan S M; Thabit, Romany H

    2014-10-01

    The transcription factor, nuclear factor-κB (NF-κB) is a key inducer of inducible nitric oxide synthase (iNOS) gene expression. The aim of the present study was to investigate the potential protective effect of l-arginine (Arg; nitric oxide precursor) and aminoguanidine (inducible nitric oxide synthase inhibitor) against acetic acid (AA)-induced colitis in rats, and the potential role of NF-κB. Colitis was induced by intrarectal inoculation of rats with 4% acetic acid for three consecutive days. The effect of Arg and aminoguanidine on nitric oxide levels was assessed by Greiss assay and protein expression of NF-κB/p65, and inducible nitric oxide synthase was also investigated by immunohistochemistry. Slides were examined using ImageJ, and results reported as the percent area positive for each marker. Intrarectal AA caused a significant increase in bodyweight loss and colon weights. Arg at 100 mg/day for 7 days before induction of colitis diminished the changes in both bodyweight loss and colon weights. Furthermore, Arg attenuated the colonic tissues macroscopic and microscopic damage induced by acetic acid. In addition, i.p. AG 100 mg/kg given during and after induction of colitis recovered the colonic ulcerative lesion induced by AA. Arg can protect against colonic inflammation; an effect that probably be attributed to its nitric oxide-donating property, resulting in modulatory effects on the expression of NF-κB/p65 in the colon tissues. The results suggested that Arg might reduce the inflammation associated with colitis as confirmed by histopathological investigations. Arg might inhibit AA-induced colitis through the NF-κB/nitric oxide pathway.

  8. 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.

  9. 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.

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

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

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    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.

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

    OpenAIRE

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

    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...

  13. Ethyl acetate extracts of alfalfa (Medicago sativa L. sprouts inhibit lipopolysaccharide-induced inflammation in vitro and in vivo

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    Chen Miaw-Ling

    2009-07-01

    Full Text Available Abstract This study aimed to investigate if food components that exert anti-inflammatory effects may be used for inflammatory disorders by examining alfalfa sprout ethyl acetate extract (ASEA. The cytokine profile and life span of BALB/c mice with acute inflammation after intra-peritoneal (ip injection of 15 mg/kg BW lipopolysaccharide (LPS were determined. The results showed that the life span of LPS-induced inflammatory mice were negatively correlated with serum levels of TNF-α, IL-6, and IL-1β at 9 hr after LPS-injection, which indicated that suppressing these cytokines in the late phase of inflammation may be beneficial for survival. The in vitro experiment then showed that ASEA significantly reduced IL-6 and IL-1β production and the NF-κB trans-activation activity of mitogen-stimulated RAW264.7 cells. To further evaluate the anti-inflammatory effects of ASEA in vivo, BALB/c mice were tube-fed with 25 mg ASEA/kg BW/day in 50 μl sunflower oil, while the control and PDTC (pyrrolidine dithiocarbamate, an anti-inflammatory agent groups were tube-fed with 50 μl sunflower oil/day only. After one week of tube-feeding, the PDTC group was injected with 50 mg/kg BW PDTC and one hour later, all of the mice were injected with 15 mg/kg BW LPS. The results showed that the ASEA and PDTC groups had significantly lower serum TNF-α, IL-6, and IL-1β levels at 9 hr after LPS challenge, and significantly higher survival rates than the control group. This study suggests that ASEA supplementation can suppress the production of pro-inflammatory cytokines and alleviate acute inflammatory hazards.

  14. Prophylactic effect of Nigella sativa against lead acetate induced changes in spermiogram, reproductive hormones and gonadal histology of rats

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    Mohammed Abdulrazzaq Assi

    2016-11-01

    Full Text Available Aim: This study was designed to evaluate the prophylactic effect of Nigella sativa (NS treatment on toxic effects induced by lead acetate (LA on the reproductive hormones, spermiogram and gonadal histology of rats. Materials and Methods: A total of 20 Sprague-Dawley rats were divided into four groups of five rats each. Group 1 (negative control [NC] was the NC and was given distilled water, Group 2 served as the positive control (PC and was administered 10 mg/kg/day of LA per overall survival (OS, Group 3 (T1 was administered 200 mg/kg/daily of NS per OS for a month, and Group 4 (T2 was pretreated with 200 mg/kg/daily of NS per OS for 1 month, followed by 10 mg/kg/daily of LA alone per OS for another. The rats were euthanized at the end of the experimental period for collection of blood and the right caudal epididymis and testis. Serum was used for determination of reproductive hormones by using radioimmunoassay kits. The epididymal segment was cut and homogenized in phosphate-buffered saline, and the homogenate was used for determination of the spermiogram parameters such as sperm concentration, sperm viability, percentage of live sperm, motility and abnormality. Both the epididymis and testis were fixed in 10% buffered formalin for histological processing. Results: The sperm concentration, general, and individual motilities were higher (p0.05 between control and T2. The concentration of follicle-stimulating hormone (FSH was comparable (p>0.05 in all groups, while testosterone (TS hormone concentration was lower (p<0.05 in the PC and higher in the control and T1 groups. Conclusion: This study showed the preventive effects of NS administration against alterations in reproductive hormnes, sperm parameters and gonadal histology caused by LA in rats.

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

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    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.

  16. Fyn and Src are Effectors of Oncogenic EGFR Signaling in Glioblastoma Patients

    Science.gov (United States)

    Lu, Kan V.; Zhu, Shaojun; Cvrljevic, Anna; Huang, Tiffany T.; Sarkaria, Shawn; Ahkavan, David; Dang, Julie; Dinca, Eduard B.; Plaisier, Seema B.; Oderberg, Isaac; Lee, Yohan; Chen, Zugen; Caldwell, Jeremy S.; Xie, Yongmin; Loo, Joseph A.; Seligson, David; Chakravari, Arnab; Lee, Francis Y.; Weinmann, Roberto; Cloughesy, Timothy F.; Nelson, Stanley F.; Bergers, Gabriele; Graeber, Thomas; Furnari, Frank B.; James, C. David; Cavenee, Webster K.; Johns, Terrance G.; Mischel, Paul S.

    2009-01-01

    Activating EGFR mutations are common in many cancers including glioblastoma. However, clinical responses to EGFR inhibitors are infrequent and short-lived. We demonstrate that the Src family kinases (SFKs) Fyn and Src are effectors of oncogenic EGFR signaling, enhancing invasion and tumor cell survival in vivo. Expression of a constitutively active EGFR mutant, EGFRvIII, resulted in activating phosphorylation and physical association with Src and Fyn, promoting tumor growth and motility. Gene silencing of Fyn and Src limited EGFR and EGFRvIII-dependent tumor cell motility. The SFK inhibitor dasatinib inhibited invasion, promoted tumor regression and induced apoptosis in vivo, significantly prolonging survival of an orthotopic glioblastoma model expressing endogenous EGFRvIII. Dasatinib enhanced the efficacy of an anti-EGFR monoclonal antibody (mAb 806) in vivo, further limiting tumor growth and extending survival. Examination of a large cohort of clinical samples demonstrated frequent coactivation of EGFR and SFKs in glioblastoma patients. These results establish a mechanism linking EGFR signaling with Fyn and Src activation to promote tumor progression and invasion in vivo and provide rationale for combined anti-EGFR and anti-SFK targeted therapies. PMID:19690143

  17. 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.

  18. Development of new mouse lung tumor models expressing EGFR T790M mutants associated with clinical resistance to kinase inhibitors.

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    Lucia Regales

    Full Text Available BACKGROUND: The EGFR T790M mutation confers acquired resistance to kinase inhibitors in human EGFR mutant lung adenocarcinoma, is occasionally detected before treatment, and may confer genetic susceptibility to lung cancer. METHODOLOGY/PRINCIPAL FINDINGS: To study further its role in lung tumorigenesis, we developed mice with inducible expression in type II pneumocytes of EGFR(T790M alone or together with a drug-sensitive L858R mutation. Both transgenic lines develop lung adenocarcinomas that require mutant EGFR for tumor maintenance but are resistant to an EGFR kinase inhibitor. EGFR(L858R+T790M-driven tumors are transiently targeted by hsp90 inhibition. Notably, EGFR(T790M-expressing animals develop tumors with longer latency than EGFR(L858R+T790M-bearing mice and in the absence of additional kinase domain mutations. CONCLUSIONS/SIGNIFICANCE: These new mouse models of mutant EGFR-dependent lung adenocarcinomas provide insight into clinical observations. The models should also be useful for developing improved therapies for patients with lung cancers harboring EGFR(T790M alone or in conjunction with drug-sensitive EGFR kinase domain mutations.

  19. Folic acid protects against lead acetate-induced hepatotoxicity by decreasing NF-κB, IL-1β production and lipid peroxidation mediataed cell injury.

    Science.gov (United States)

    Abd Allah, Eman S H; Badary, Dalia M

    2017-03-01

    Folic acid plays an important role in cellular metabolic activities. The present study was designed to investigate the protective effect of folic acid against lead acetate-induced hepatotoxicity. Twenty four male Wistar albino rats were randomly divided into four groups, six animals each. Negative control group received the vehicle, positive control group received 1mg/kg folic acid for five consecutive days/week for 4 weeks orally, lead-exposed group received 10mg/kg lead acetate intraperitoneally (IP) for five consecutive days/week for 4 weeks, and lead-treated group received 10mg/kg lead acetate IP and 1mg/kg folic acid orally for five consecutive days/week for 4 weeks concurrently. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and γ- glutamyltransferase (GGT) were measured. Hepatic total peroxide and interleukin-1β (IL-1β) were also investigated. Histopathological studies using hematoxylin-eosin (H&E) and periodic acid shiff's (PAS) were carried out. The expression of nuclear factor kappa B (NF-κB) was evaluated using immunohistochemistry. Serum AST, ALT and GGT and hepatic total peroxide and IL-1β were significantly increased in lead-exposed group and were positively correlated with hepatic lead level. Moreover, lead-exposed rats showed hydropic degeneration, nuclear vesiculation, high lymphocytic infiltration, depletion of glycogen content and NF-κB expression. Concomitant folic acid administration resulted in a significant alleviation of biochemical and structural alteration-induced by lead. This was associated with reduction of hepatic total peroxide and IL-1β and reduction of NF-κB expression. In conclusion, folic acid protects against lead acetate-induced hepatotoxicity by decreasing NF-κB, IL-1β production and lipid peroxidation mediataed cell injury.

  20. Effect of Azadirachta indica leaves extract on acetic acid-induced colitis in rats:Role of antioxidants, free radicals and myeloperoxidase

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    Ghatule RR

    2012-10-01

    Full Text Available Objective: To evaluate the healing effects of extract of dried leaves of Azadirachta indica (Neem on acetic acid-induced colitis in rats. Neem tree is known as ‘arishtha ’ in Sanskrit, meaning ‘reliever of sicknesses ’. Methods: 50% ethanolic extract of Azadirachta indica leaves was administered orally, once daily for 14 days in rats after the induction of colitis with acetic acid and 500 mg/kg dose of extract was found to have an optimal effect against acetic acid-induced colonic damage score, weight and adhesions (Macroscopic. Effect of Azadirachta indica extract was then further studied on various physical (mucous/blood in stool, food and water intake and body weight changes, colonic mucosal damage and inflammation (microscopic, antibacterial and biochemical parameters viz. i antioxidants (superoxide dismutase, catalase and reduced glutathione and ii free radicals (nitric oxide and lipid peroxidation and myeloperoxidase (acute inflammatory marker activities in acetic acid-induced colitis. Results: Azadirachta indica extract decreased colonic mucosal damage and inflammation (macroscopic and microscopic, mucous/bloody diarrhea, fecal frequency and increased body weight. Azadirachta indica extract showed intestinal antibacterial activity and enhanced the antioxidants but decreased free radicals and myeloperoxidase activities. Acute toxicity study indicated no mortality or other ANS or CNS related adverse effects even with 5.0 g/kg dose (10 times of effective dose indicating its safety. Conclusions: Azadirachta indica seemed to be safe and effective in colitis by its predominant effect on promoting antioxidant status and decreasing intestinal bacterial load, free radicals and myeloperoxidase responsible for tissue damage and delayed healing.

  1. Effect of 12-O-tetradecanoylphorbol-13-acetate-induced psoriasis-like skin lesions on systemic inflammation and atherosclerosis in hypercholesterolaemic apolipoprotein E deficient mice

    DEFF Research Database (Denmark)

    Madsen, Marie; Hansen, Peter Riis; Nielsen, Lars Bo;

    2016-01-01

    to develop an animal model with combined atherosclerosis and psoriasis-like skin inflammation. METHODS: Topical 12-O-tetradecanoylphorbol-13-acetate (TPA) was applied to the ears twice per week for 8 weeks in atherosclerosis-prone apolipoprotein E deficient (ApoE(-/-)) mice. RESULTS: TPA led to localized......, respectively. However, atherosclerotic plaque area and composition, and mRNA levels of several inflammatory genes in the aortic wall were not significantly affected by TPA-induced skin inflammation. CONCLUSIONS: TPA-induced psoriasis-like skin inflammation in atherosclerosis-prone ApoE(-/-) mice evoked...

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

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    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.

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

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    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

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

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    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.

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

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    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.

  6. 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

  7. PARP Inhibition Suppresses Growth of EGFR-Mutant Cancers by Targeting Nuclear PKM2

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    Nan Li

    2016-04-01

    Full Text Available Upon growth factor stimulation or in some EGFR mutant cancer cells, PKM2 translocates into the nucleus to induce glycolysis and cell growth. Here, we report that nuclear PKM2 binds directly to poly-ADP ribose, and this PAR-binding capability is critical for its nuclear localization. Accordingly, PARP inhibition prevents nuclear retention of PKM2 and therefore suppresses cell proliferation and tumor growth. In addition, we found that PAR level correlates with nuclear localization of PKM2 in EGFR mutant brain and lung cancers, suggesting that PAR-dependent nuclear localization of PKM2 likely contributes to tumor progression in EGFR mutant glioblastoma and lung cancers. In addition, some EGFR-inhibitor-resistant lung cancer cells are sensitive to PARP inhibitors. Taken together, our data indicate that suppression of PKM2 nuclear function by PARP inhibitors represents a treatment strategy for EGFR-inhibitor-resistant cancers.

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

    Science.gov (United States)

    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

    2015-04-01

    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 to MET and ALK inhibitors in non-small cell lung cancers (NSCLCs). We found that SMARCE1 binds to regulatory regions of the EGFR locus and suppresses EGFR transcription in part through regulating expression of Polycomb Repressive Complex component CBX2. Addition of the EGFR inhibitor gefitinib restores the sensitivity of SMARCE1-knockdown cells to MET and ALK inhibitors in NSCLCs. Our findings link SMARCE1 to EGFR oncogenic signaling and suggest targeted treatment options for SMARCE1-deficient tumors.

  9. Development of a human epidermal growth factor derivative with EGFR-blocking and depleted biological activities: A comparative in vitro study using EGFR-positive breast cancer cells.

    Science.gov (United States)

    Mehrabi, Masomeh; Mansouri, Kamran; Soleymani, Bijan; Hoseinkhani, Zohreh; Shahlaie, Mohsen; Khodarahmi, Reza

    2017-10-01

    Epidermal growth factor (EGF) is a local growth factor that stimulates cell growth, proliferation, and differentiation by binding to its receptor EGFR. EGF and EGFR are involved in many aspects of the development of carcinomas. Because EGFR has been found to be over-expressed in many tumors of epithelial origin, it is a potential target for antitumor therapy. In this study we designed a mutated form of hEGF (mEGF) with a deletion of four amino acids residues (Gln(43), Tyr(44), Arg(45) and Asp(46)) in order to show importance of Leu spatial location for EGFR binding/activation. Expression vector pET32a(+) and E. Coli, strain Rosetta-gami B (DE3) were used to enhance solubility of the recombinant protein with yielding approximately 10mg/l of cell culture. The purified cleaved hEGF as well as non-cleaved fusion protein were biologically active, which was confirmed by their equal ability to stimulate proliferation of MCF7 cells. The mEGF showed specificity and high affinity for EGFR binding, however binding affinity of mEGF for EGFR was reduced about 11.5 fold compared with that of hEGF. The mEGF effect on the MCF7 cell proliferation had a relatively different outcome; mEGF simulated differential cell growth in a dose dependent manner. On the other hand, in MDA-MB468 cells, hEGF and mEGF induced growth inhibition, which was much more severe for hEGF than that of mEGF. Also, hEGF strongly induced the phosphorylation of EGF receptor in MDA-MB468 cells while mEGF induced poor EGFR phosphorylation. The same observations were also made for migration of cancer cells, especially induction of MDA-MB468 migration by mEGF was significantly lower than that of hEGF, suggesting a connection between tyrosine phosphorylation of EGFR and cell migration. Docking analysis revealed that the binding affinity and the buried surface area of mEGF to EGFR complex are lower than those of hEGF/EGFR. Although theoretical studies confirmed reduction in mEGF-EGFR binding affinity, the data of the

  10. Effect of the BRCA1-SIRT1-EGFR axis on cisplatin sensitivity in ovarian cancer.

    Science.gov (United States)

    Li, Da; Wu, Qi-Jun; Bi, Fang-Fang; Chen, Si-Lei; Zhou, Yi-Ming; Zhao, Yue; Yang, Qing

    2016-01-01

    There is accumulating evidence that breast cancer 1 (BRCA1), sirtuin 1 (SIRT1), and epidermal growth factor receptor (EGFR) help to modulate cisplatin cytotoxicity. The role of dynamic crosstalk among BRCA1, SIRT1, and EGFR in cisplatin sensitivity remains largely unknown. We found that BRCA1, SIRT1, and EGFR levels were increased in cisplatin-resistant ovarian cancers compared with those in cisplatin-sensitive ovarian cancers. Hypomethylation in the BRCA1 promoter was associated with BRCA1 activation, significantly elevated SIRT1 levels, decreased nicotinamide adenine dinucleotide (NAD)-mediated SIRT1 activity, and decreased EGFR levels. Treatment with 5 and 10 μg/ml cisplatin induced a gradual increase in BRCA1 and SIRT1 levels and a gradual decrease in NAD levels and NAD-mediated SIRT1 activity, whereas EGFR levels were increased or decreased by treatment with 5 or 10 μg/ml cisplatin, respectively. The overexpression of SIRT1 or the enhancement of SIRT1 activity synergistically enhanced the BRCA1-mediated effects on EGFR transcription. In contrast, the knockdown of SIRT1 or the inhibition of SIRT1 activity inhibited the BRCA1-mediated effects on EGFR transcription. BRCA1 regulates EGFR through a BRCA1-mediated balance between SIRT1 expression and activity. Those results improve our understanding of the basic molecular mechanism underlying BRCA1-related cisplatin resistance in ovarian cancer.

  11. 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.

  12. 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.

  13. Analysis of origin and protein-protein interaction maps suggests distinct oncogenic role of nuclear EGFR during cancer evolution

    Science.gov (United States)

    Sharip, Ainur; Abdukhakimova, Diyora; Wang, Xiao; Kim, Alexey; Kim, Yevgeniy; Sharip, Aigul; Orakov, Askarbek; Miao, Lixia; Sun, Qinglei; Chen, Yue; Chen, Zhenbang; Xie, Yingqiu

    2017-01-01

    Receptor tyrosine kinase EGFR usually is localized on plasma membrane to induce progression of many cancers including cancers in children (Bodey et al. In Vivo. 2005, 19:931-41), but it contains a nuclear localization signal (NLS) that mediates EGFR nuclear translocation (Lin et al. Nat Cell Biol. 2001, 3:802-8). Here we report that NLS of EGFR has its old evolutionary origin. Protein-protein interaction maps suggests that nEGFR pathways are different from membrane EGFR and EGF is not found in nEGFR network while androgen receptor (AR) is found, which suggests the evolution of prostate cancer, a well-known AR driven cancer, through changes in androgen- or EGF-dependence. Database analysis suggests that nEGFR correlates with the tumor grades especially in prostate cancer patients. Structural predication analysis suggests that NLS can compromise the differential protein binding to EGFR through stretch linkers with evolutionary mutation from N to V. In experiment, elevation of nEGFR but not membrane EGFR was found in castration resistant prostate cancer cells. Finally, systems analysis of NLS and transmembrane domain (TM) suggests that NLS has old origin while NLS neighboring domain of TM has been undergone accelerated evolution. Thus nEGFR has an old origin resembling the cancer evolution but TM may interfere with NLS driven signaling for natural selection of survival to evade NLS induced aggressive cancers. Our data suggest NLS is a dynamic inducer of EGFR oncogenesis during evolution for advanced cancers. Our model provides novel insights into the evolutionary role of NLS of oncogenic kinases in cancers.

  14. 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.

  15. Ethyl acetate fraction of Amomum xanthioides improves bile duct ligation-induced liver fibrosis of rat model via modulation of pro-fibrogenic cytokines

    OpenAIRE

    Hyeong-Geug Kim; Jong-Min Han; Jin-Seok Lee; Jong Suk Lee; Chang-Gue Son

    2015-01-01

    We investigated anti-hepatofibrotic effects of ethyl acetate fraction of Ammomum xanthoides (EFAX) using bile duct ligation (BDL)-induced hepatic fibrosis in a rat model. Male SD rats (6 weeks old) underwent BDL followed by 15 days of orall administration of EFAX (12.5, 25 or 50 mg/kg) or ursodeoxycholic acid (25 mg/kg). BDL caused animal death, ascites formation, alterations in serum biochemistries, and severe hepatic injury with excessive collagen deposition, whereas EFAX treatment signific...

  16. 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.

  17. Sulforaphane attenuates EGFR signaling in NSCLC cells.

    Science.gov (United States)

    Chen, Chi-Yuan; Yu, Zhu-Yun; Chuang, Yen-Shu; Huang, Rui-Mei; Wang, Tzu-Chien V

    2015-06-03

    EGFR, a receptor tyrosine kinase (RTK), is frequently overexpressed and mutated in non-small cell lung cancer (NSCLC). Tyrosine kinase inhibitors (TKIs) have been widely used in the treatment of many cancers, including NSCLC. However, intrinsic and acquired resistance to TKI remains a common obstacle. One strategy that may help overcome EGFR-TKI resistance is to target EGFR for degradation. As EGFR is a client protein of heat-shock protein 90 (HSP90) and sulforaphane is known to functionally regulate HSP90, we hypothesized that sulforaphane could attenuate EGFR-related signaling and potentially be used to treat NSCLC. Our study revealed that sulforaphane displayed antitumor activity against NSCLC cells both in vitro and in vivo. The sensitivity of NSCLC cells to sulforaphane appeared to positively correlate with the inhibition of EGFR-related signaling, which was attributed to the increased proteasomal degradation of EGFR. Combined treatment of NSCLC cells with sulforaphane plus another HSP90 inhibitor (17-AAG) enhanced the inhibition of EGFR-related signaling both in vitro and in vivo. We have shown that sulforaphane is a novel inhibitory modulator of EGFR expression and is effective in inhibiting the tumor growth of EGFR-TKI-resistant NSCLC cells. Our findings suggest that sulforaphane should be further explored for its potential clinical applications against NSCLC.

  18. Inhibition of triple-negative breast cancer models by combinations of antibodies to EGFR

    Science.gov (United States)

    Ferraro, Daniela A.; Gaborit, Nadège; Maron, Ruth; Cohen-Dvashi, Hadas; Porat, Ziv; Pareja, Fresia; Lavi, Sara; Lindzen, Moshit; Ben-Chetrit, Nir; Sela, Michael; Yarden, Yosef

    2013-01-01

    Breast tumors lacking expression of human epidermal growth factor receptor 2 (HER2) and the estrogen and the progesterone receptors (triple negative; TNBC) are more aggressive than other disease subtypes, and no molecular targeted agents are currently available for their treatment. Because TNBC commonly displays EGF receptor (EGFR) expression, and combinations of monoclonal antibodies to EGFR effectively inhibit other tumor models, we addressed the relevance of this strategy to treatment of TNBC. Unlike a combination of the clinically approved monoclonal antibodies, cetuximab and panitumumab, which displaced each other and displayed no cooperative effects, several other combinations resulted in enhanced inhibition of TNBC’s cell growth both in vitro and in animals. The ability of certain antibody mixtures to remove EGFR from the cell surface and to promote its intracellular degradation correlated with the inhibitory potential. However, unlike EGF-induced sorting of EGFR to lysosomal degradation, the antibody-induced pathway displayed independence from the intrinsic kinase activity and dimer formation ability of EGFR, and it largely avoided the recycling route. In conclusion, although TNBC clinical trials testing EGFR inhibitors reported lack of benefit, our results offer an alternative strategy that combines noncompetitive antibodies to achieve robust degradation of EGFR and tumor inhibition. PMID:23319610

  19. 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.

  20. Galangin and kaempferol suppress phorbol-12-myristate-13-acetate-induced matrix metalloproteinase-9 expression in human fibrosarcoma HT-1080 cells.

    Science.gov (United States)

    Choi, Yu Jung; Lee, Young Hun; Lee, Seung-Taek

    2015-01-01

    Matrix metalloproteinase (MMP)-9 degrades type IV collagen in the basement membrane and plays crucial roles in several pathological implications, including tumorigenesis and inflammation. In this study, we analyzed the effect of flavonols on MMP-9 expression in phorbol-12-myristate-13-acetate (PMA)-induced human fibrosarcoma HT-1080 cells. Galangin and kaempferol efficiently decreased MMP-9 secretion, whereas fisetin only weakly decreased its secretion. Galangin and kaempferol did not affect cell viability at concentrations up to 30 μM. Luciferase reporter assays showed that galangin and kaempferol decrease transcription of MMP-9 mRNA. Moreover, galangin and kaempferol strongly reduce IκBα phosphorylation and significantly decrease JNK phosphorylation. These results indicate that galangin and kaempferol suppress PMA-induced MMP-9 expression by blocking activation of NF-κB and AP-1. Therefore, these flavonols could be used as chemopreventive agents to lower the risk of diseases involving MMP-9.

  1. 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.

  2. Combined inhibition of IGFR enhances the effects of gefitinib in H1650: a lung cancer cell line with EGFR mutation and primary resistance to EGFR-TK inhibitors.

    Science.gov (United States)

    Choi, Yun Jung; Rho, Jin Kyung; Jeon, Byung-suk; Choi, Su Jin; Park, Su Cheol; Lee, Seung Sook; Kim, Hye-Ryoun; Kim, Cheol Hyeon; Lee, Jae Cheol

    2010-07-01

    H1650 non-small cell lung cancer (NSCLC) cells display primary resistance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) although they have a deletion mutation on exon 19 of the EGFR gene. We investigated the effect of inhibition of both insulin-like growth factor receptor (IGFR) and EGFR signaling considering that IGFR signaling pathway has been implicated in the development and progression with therapeutic resistance of various cancers including lung cancer. Three human NSCLC cell lines with an EGFR mutation of PC-9, HCC827 and H1650 were used for experiment. Cell viability and proliferative activity were assessed by MTT and three-dimensional culture assay. Combination index was obtained by CalcuSyn software. The change of EGFR- and IGFR-related signals was evaluated by western blots. H1650 cells were 1,000 times more resistant to gefitinib and erlotinib than HCC827 and PC-9 cells possessing the same EGFR mutation. Phosphatase and tensin homolog loss and sustained phosphorylation of Akt in spite of treatment with gefitinib were evident only in H1650 cells. Interestingly, IGFR phosphorylation was decreased by gefitinib in HCC827 and PC-9 cells while being maintained in H1650 cells. Combined treatment with the IGFR inhibitors alpha-IR3 and AG1024 enhanced gefitinib-induced growth inhibition and apoptosis, and down-regulated phosphorylation of Akt, EGFR and IGFR. Combined inhibition of IGFR signaling enhances the growth inhibitory and apoptosis-inducing effects of gefitinib, suggesting that this approach could be useful to overcome the primary resistance to EGFR-TKIs in lung cancer.

  3. Therapeutic and recurrence-preventing effects of Qi-Replenishing and Blood-Activating Formula in rats with acetic acid-induced gastric ulcer

    Institute of Scientific and Technical Information of China (English)

    Guo-Rong Jiang; Hui-Nan Ge; Guo-Qiang Liang; Liang Zhou; Lu-Rong Zhang

    2016-01-01

    Objective: To explore the therapeutic and recurrence-preventing effects of Qi-Replenishing and Blood-Activating Formula in rats with acetic acid-induced gastric ulcer. Methods: A total of 138 SD rats were selected to make rat models with gastric ulcer induced by acetic acid (24 rats with sham operation served as sham operation group), and were randomly divided into model group (n=30), western medicine group (n=30), traditional Chinese medicine (TCM) group (n=24) and combination group (combined western medicine and TCM group, n=30). Western medicine group was gavaged with omeprazole in the morning and with iso-volumetric distilled water in the afternoon; TCM group and TCM sham operation group were gavaged with iso-volumetric distilled water in the morning and with Qi-Replenishing and Blood-Activating Formula in the afternoon;combination group was gavaged with omeprazole in the morning and with Qi-Replenishing and Blood-Activating Formula in the afternoon; sham operation group and model group were gavaged with iso-volumetric distilled water both in the morning and afternoon. Ulcer indexes and degree of mucosal degree in rats at different time points after gavage were observed. Twenty-eight days after gavage, interleukin (IL)-1β was given to induce ulcer recurrence so as to observethe recurrent severity and rate of ulcer in each group. Results: Compared with model group and western medicine group, treatment in combination group could prominently reduce the ulcer index of rats with peptic ulcer, and increase the healing rate and inhibition rate of peptic ulcer. After IL-1β-induced ulcer recurrence, combination group was significantly superior to modelgroup and western medicine group in ulcer recurrent rate [50% (3/6) vs. 100% (6/6)] and severity. Conclusions: Basic acid-suppression therapy combined with Qi-Replenishing and Blood-Activating Formula can effectually improve the ulcer healing quality and reduce ulcer recurrence.

  4. EGFR Mutation Heterogeneity and the Mixed Response to EGFR Tyrosine Kinase Inhibitors of Lung Adenocarcinomas

    OpenAIRE

    Chen, Zhi-yong; Zhong, Wen-Zhao; Zhang, Xu-Chao; Su, Jian; Yang, Xue-Ning; Chen, Zhi-Hong; Yang, Jin-Ji; Zhou, Qing; Yan, Hong-Hong; An, She-Juan; Chen, Hua-Jun; JIANG, BEN-YUAN; Mok, Tony S.; Wu, Yi-Long

    2012-01-01

    Direct sequencing was used to identify EGFR mutations in 180 pairs of lung adenocarcinoma samples from the primary tumor and one metastatic site in 3,071 patients. Correlations between EGFR genetic heterogeneity and patient characteristics were examined.

  5. 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.

  6. 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.

  7. Inhibitory effects of Momordica grosvenori Swingle extracts on 12-O-tetradecanoylphorbol 13-acetate-induced skin inflammation and tumor promotion in mouse skin.

    Science.gov (United States)

    Weerawatanakorn, Monthana; Yang, Ji-Rui; Tsai, Mei-Ling; Lai, Ching-Shu; Ho, Chi-Tang; Pan, Min-Hsiung

    2014-02-01

    Our previous data showed that the Momordica grosvenori Swingle extract (MSE) exhibited the anti-inflammatory effect through markedly suppressed LPS-induced up-regulation of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2) and ODC (ornithine decarboxylase) gene expression in RAW 264.7 cells. Regarding the link between inflammation and carcinogenesis, we further investigated the bio-molecular mechanisms of both anti-inflammatory and anti-tumor activities in vivo using a TPA (12-O-tetradecanoyl phorbol 13-acetate)-stimulated mouse skin model. Pretreatment with MSE in mouse skin has led to the reduction of TPA-induced nuclear translocation of the nuclear factor-κB (NFκB) subunits as well as phosphorylation of IκBα and p65 subsequent reduction of IκBα degradation. In addition, the MSE inhibitory effect on upstream of NFκB was found to involve the transcriptional effects of MAPK signaling as indicated by strong suppression on TPA-induced activation of extracellular signal regulate kinase (ERK)1/2, p38 mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase (JNK)1/2, phosphatidylinositol 3-kinase (PI3K) and Akt. Moreover, MSE significantly inhibited 7,12-dimethylbenz[a]anthracene (DMBA)-TPA-induced skin tumor formation in mice measured by the tumor multiplicity of papillomas at 20 weeks. The results suggested that MSE contained promising functional ingredients capable of preventing inflammation-associated tumorigenesis.

  8. 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.

  9. 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.

  10. Neuroprotective effects of the Phellinus linteus ethyl acetate extract against H2O2-induced apoptotic cell death of SK-N-MC cells.

    Science.gov (United States)

    Choi, Doo Jin; Cho, Sarang; Seo, Jeong Yeon; Lee, Hyang Burm; Park, Yong Il

    2016-01-01

    Numerous studies have suggested that neuronal cells are protected against oxidative stress-induced cell damage by antioxidants, such as polyphenolic compounds. Phellinus linteus (PL) has traditionally been used to treat various symptoms in East Asian countries. In the present study, we prepared an ethyl acetate extract from the fruiting bodies of PL (PLEA) using hot water extraction, ethanol precipitation, and ethyl acetate extraction. The PLEA contained polyphenols as its major chemical component, and thus, we predicted that it may exhibit antioxidant and neuroprotective effects against oxidative stress. The results showed that the pretreatment of human brain neuroblastoma SK-N-MC cells with the PLEA (0.1-5 μg/mL) significantly and dose-dependently reduced the cytotoxicity of H2O2 and the intracellular ROS levels and enhanced the expression of HO-1 (heme oxygenase-1) and antioxidant enzymes, such as CAT (catalase), GPx-1 (glutathione peroxidase-1), and SOD-1 and -2 (superoxide dismutase-1 and -2). The PLEA also directly scavenged free radicals. PLEA pretreatment also significantly attenuated DNA fragmentation and suppressed the mRNA expression and activation of mitogen-activated protein kinases extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38 kinase, which are induced by oxidative stress and lead to cell death. PLEA pretreatment inhibited the activation of the apoptosis-related proteins caspase-3 and poly (ADP-ribose) polymerase. These results demonstrate that the PLEA has neuroprotective effects against oxidative stress (H2O2)-induced neuronal cell death via its antioxidant and anti-apoptotic properties. PLEA should be investigated in an in vivo model on its potential to prevent or ameliorate neurodegenerative disease.

  11. Hydroethanolic extract of Baccharis trimera promotes gastroprotection and healing of acute and chronic gastric ulcers induced by ethanol and acetic acid.

    Science.gov (United States)

    Dos Reis Lívero, Francislaine Aparecida; da Silva, Luisa Mota; Ferreira, Daniele Maria; Galuppo, Larissa Favaretto; Borato, Debora Gasparin; Prando, Thiago Bruno Lima; Lourenço, Emerson Luiz Botelho; Strapasson, Regiane Lauriano Batista; Stefanello, Maria Élida Alves; Werner, Maria Fernanda de Paula; Acco, Alexandra

    2016-09-01

    Ethanol is a psychoactive substance highly consumed around the world whose health problems include gastric lesions. Baccharis trimera is used in folk medicine for the treatment of gastrointestinal disorders. However, few studies have evaluated its biological and toxic effects. To validate the popular use of B. trimera and elucidate its possible antiulcerogenic and cytotoxic mechanisms, a hydroethanolic extract of B. trimera (HEBT) was evaluated in models of gastric lesions. Rats and mice were used to evaluate the protective and antiulcerogenic effects of HEBT on gastric lesions induced by ethanol, acetic acid, and chronic ethanol consumption. The effects of HEBT were also evaluated in a pylorus ligature model and on gastrointestinal motility. The LD50 of HEBT in mice was additionally estimated. HEBT was analyzed by nuclear magnetic resonance, and a high-performance liquid chromatography fingerprint analysis was performed. Oral HEBT administration significantly reduced the lesion area and the oxidative stress induced by acute and chronic ethanol consumption. However, HEBT did not protect against gastric wall mucus depletion and did not alter gastric secretory volume, pH, or total acidity in the pylorus ligature model. Histologically, HEBT accelerated the healing of chronic gastric ulcers in rats, reflected by contractions of the ulcer base. Flavonoids and caffeoylquinic acids were detected in HEBT, which likely contributed to the therapeutic efficacy of HEBT, preventing or reversing ethanol- and acetic acid-induced ulcers, respectively. HEBT antiulcerogenic activity may be partially attributable to the inhibition of free radical generation and subsequent prevention of lipid peroxidation. Our results indicate that HEBT has both gastroprotective and curative activity in animal models, with no toxicity.

  12. 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.

  13. 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.

  14. SCF/c-kit signaling is required in 12-O-tetradecanoylphorbol-13-acetate-induced migration and differentiation of hair follicle melanocytes for epidermal pigmentation.

    Science.gov (United States)

    Qiu, Weiming; Yang, Ke; Lei, Mingxing; Yan, Hongtao; Tang, Hui; Bai, Xiufeng; Yang, Guihong; Lian, Xiaohua; Wu, Jinjin

    2015-05-01

    Hair follicle melanocyte stem cells (McSCs) are responsible for hair pigmentation and also function as a major melanocyte reservoir for epidermal pigmentation. However, the molecular mechanism promoting McSCs for epidermal pigmentation remains elusive. 12-O-tetradecanoylphorbol-13-acetate (TPA) mimics key signaling involved in melanocyte growth, migration and differentiation. We therefore investigated the molecular basis for the contribution of hair follicle McSCs to epidermal pigmentation using the TPA induction model. We found that repetitive TPA treatment of female C57BL/6 mouse dorsal skin induced epidermal pigmentation by increasing the number of epidermal melanocytes. Particularly, TPA treatment induced McSCs to initiate proliferation, exit the stem cell niche and differentiate. We also demonstrated that TPA promotes melanoblast migration and differentiation in vitro. At the molecular level, TPA treatment induced robust expression of stem cell factor (SCF) in keratinocytes and c-kit in melanoblasts and melanocytes. Administration of ACK2, a neutralizing antibody against the Kit receptor, suppressed mouse epidermal pigmentation, decreased the number of epidermal melanocytes, and inhibited melanoblast migration. Taken together, our data demonstrate that TPA promotes the expansion, migration and differentiation of hair follicle McSCs for mouse epidermal pigmentation. SCF/c-kit signaling was required for TPA-induced migration and differentiation of hair follicle melanocytes. Our findings may provide an excellent model to investigate the signaling mechanisms regulating epidermal pigmentation from mouse hair follicle McSCs, and a potential therapeutic option for skin pigmentation disorders.

  15. Effect of 12-O-tetradecanoylphorbol-13-acetate-induced psoriasis-like skin lesions on systemic inflammation and atherosclerosis in hypercholesterolaemic apolipoprotein E deficient mice

    DEFF Research Database (Denmark)

    Madsen, Marie; Hansen, Peter Riis; Nielsen, Lars Bo;

    2016-01-01

    skin inflammation with increased epidermal thickness, infiltration of inflammatory-like cells and augmented tissue interleukin-17F levels. Systemic effects of the topical application of TPA were demonstrated by increased plasma concentration of serum amyloid A and splenic immune modulation...... systemic immune-inflammatory effects, but did not affect atherogenesis. The results may question the role of psoriasis-induced inflammation in the pathogenesis of atherosclerosis in psoriasis patients....... to develop an animal model with combined atherosclerosis and psoriasis-like skin inflammation. METHODS: Topical 12-O-tetradecanoylphorbol-13-acetate (TPA) was applied to the ears twice per week for 8 weeks in atherosclerosis-prone apolipoprotein E deficient (ApoE(-/-)) mice. RESULTS: TPA led to localized...

  16. 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.

  17. 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.

  18. 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.

  19. 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.

  20. 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)

    Song Tusheng; Yang Ling; Huang Chen; Liu Liying; Ni Lei; Wang Aiying; Luo Yu

    2007-01-01

    Objective To investigate the mechanisms of apoptosis induced in Human leukemia cell line K562 by the combination of indole-3-acetic acid and horseradish peroxidase. Methods Human leukemia cell line K562 were exposed to indole-3-acetic acid (IAA) at 20, 40, 60, 80 or 100 mol/L and horseradish peroxidase(HRP) at 1.2 g/mL for varying times. MTT assay was applied to detect the cell proliferation. Flow cytometry was performed to detect the arrest of cell cycle. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay was used to measure apoptosis. 2, 7-dichlorofluorescin diacetate (DCFH-DA) uptake was measured to determine free radical by confocal microscope. Content of malondiadehyde (MDA) and activity of superoxide dismutase (SOD) were measured by biochemical methods. Results IAA/HRP initiated growth inhibition of K562 cells in a dose- and time-dependent manner. Flow cytometry revealed that cell cycle arrested at G1/G0 after 24 hours treatment. After 72 hours treatment, apoptotic rate of 100 mol/L IAA group increased to 43.9%, which was 5 times that of control(P<0.01). Content of MDA and activity of SOD increased respectively in treatments compared with control. Meanwhile, IAA/HRP stimulated the formation of free radical, which was increased by IAA concentration-dependently. Conclusion The combination of IAA and HRP can inhibit the growth of Human leukemia cell line K562 in vitro by inducing apoptosis which is associated with the increase of free radical. The combination of IAA and HRP might be a promising chemopreventive and chemotherapeutic agent against human leukemia.

  1. Heterogeneous EGFR gene copy number increase is common in colorectal cancer and defines response to anti-EGFR therapy.

    Directory of Open Access Journals (Sweden)

    Annika Ålgars

    Full Text Available Anti-EGFR therapy is commonly used to treat colorectal cancer (CRC, although only a subset of patients benefit from the treatment. While KRAS mutation predicts non-responsiveness, positive predictive markers are not in clinical practice. We previously showed that immunohistochemistry (IHC-guided EGFR gene copy number (GCN analysis may identify CRC patients benefiting from anti-EGFR treatment. Here we tested the predictive value of such analysis in chemorefractory metastatic CRC, elucidated EGFR GCN heterogeneity within the tumors, and evaluated the association between EGFR GCN, KRAS status, and anti-EGFR antibody response in CRC cell lines. The chemorefractory patient cohort consisted of 54 KRAS wild-type (WT metastatic CRC patients. EGFR GCN status was analyzed by silver in situ hybridization using a cut-off value of 4.0 EGFR gene copies/cell. KRAS-WT and KRAS mutant CRC cell lines with different EGFR GCN were used in in vitro studies. The chemorefractory CRC tumors with EGFR GCN increase (≥4.0 responded better to anti-EGFR therapy than EGFR GCN (<4.0 tumors (clinical benefit, P = 0.0004; PFS, HR = 0.23, 95% CI 0.12-0.46. EGFR GCN counted using EGFR IHC guidance was significantly higher than the value from randomly selected areas verifying intratumoral EGFR GCN heterogeneity. In CRC cell lines, EGFR GCN correlated with EGFR expression. Best anti-EGFR response was seen with KRAS-WT, EGFR GCN = 4 cells and poorest response with KRAS-WT, EGFR GCN = 2 cells. Anti-EGFR response was associated with AKT and ERK1/2 phosphorylation, which was effectively inhibited only in cells with KRAS-WT and increased EGFR GCN. In conclusion, IHC-guided EGFR GCN is a promising predictor of anti-EGFR treatment efficacy in chemorefractory CRC.

  2. EGFR in Tumor-Associated Myeloid Cells Promotes Development of Colorectal Cancer in Mice and Associates With Outcomes of Patients.

    Science.gov (United States)

    Srivatsa, Sriram; Paul, Mariel C; Cardone, Claudia; Holcmann, Martin; Amberg, Nicole; Pathria, Paulina; Diamanti, Michaela A; Linder, Markus; Timelthaler, Gerald; Dienes, Hans P; Kenner, Lukas; Wrba, Fritz; Prager, Gerald W; Rose-John, Stefan; Eferl, Robert; Liguori, Giuseppina; Botti, Gerardo; Martinelli, Erika; Greten, Florian R; Ciardiello, Fortunato; Sibilia, Maria

    2017-07-01

    Inhibitors of the epidermal growth factor receptor (EGFR) are the first-line therapy for patients with metastatic colorectal tumors without RAS mutations. However, EGFR inhibitors are ineffective in these patients, and tumor level of EGFR does not associate with response to therapy. We screened human colorectal tumors for EGFR-positive myeloid cells and investigated their association with patient outcome. We also performed studies in mice to evaluate how EGFR expression in tumor cells and myeloid cells contributes to development of colitis-associated cancer and Apc(Min)-dependent intestinal tumorigenesis. We performed immunohistochemical and immunofluorescent analyses of 116 colorectal tumor biopsies to determine levels of EGFR in tumor and stroma; we also collected information on tumor stage and patient features and outcomes. We used the Mann-Whitney U and Kruskal-Wallis tests to correlate tumor levels of EGFR with tumor stage, and the Kaplan-Meier method to estimate patients' median survival time. We performed experiments in mice lacking EGFR in intestinal epithelial cells (Villin-Cre; Egfr(f/f) and Villin-CreER(T2); Egfr(f/f) mice) or myeloid cells (LysM-Cre; Egfr(f/f) mice) on a mixed background. These mice were bred with Apc(Min/+) mice; colitis-associated cancer and colitis were induced by administration of dextran sodium sulfate (DSS), with or without azoxymethane (AOM), respectively. Villin-CreER(T2) was activated in developed tumors by administration of tamoxifen to mice. Littermates that expressed full-length EGFR were used as controls. Intestinal tissues were collected; severity of colitis, numbers and size of tumors, and intestinal barrier integrity were assessed by histologic, immunohistochemical, quantitative reverse transcription polymerase chain reaction, and flow cytometry analyses. We detected EGFR in myeloid cells in the stroma of human colorectal tumors; myeloid cell expression of EGFR associated with tumor metastasis and shorter patient

  3. 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.

  4. EGFR as a therapeutic target in glioblastoma

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    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.

  5. Hepatitis C virus induces epidermal growth factor receptor activation via CD81 binding for viral internalization and entry.

    Science.gov (United States)

    Diao, Jingyu; Pantua, Homer; Ngu, Hai; Komuves, Laszlo; Diehl, Lauri; Schaefer, Gabriele; Kapadia, Sharookh B

    2012-10-01

    While epidermal growth factor receptor (EGFR) has been shown to be important in the entry process for multiple viruses, including hepatitis C virus (HCV), the molecular mechanisms by which EGFR facilitates HCV entry are not well understood. Using the infectious cell culture HCV model (HCVcc), we demonstrate that the binding of HCVcc particles to human hepatocyte cells induces EGFR activation that is dependent on interactions between HCV and CD81 but not claudin 1. EGFR activation can also be induced by antibody mediated cross-linking of CD81. In addition, EGFR ligands that enhance the kinetics of HCV entry induce EGFR internalization and colocalization with CD81. While EGFR kinase inhibitors inhibit HCV infection primarily by preventing EGFR endocytosis, antibodies that block EGFR ligand binding or inhibitors of EGFR downstream signaling have no effect on HCV entry. These data demonstrate that EGFR internalization is critical for HCV entry and identify a hitherto-unknown association between CD81 and EGFR.

  6. EGFR EXPRESSION IN RECTAL CANCER, RELATION TO THE FREAQUENCY OF LYMPH NODE METASTASIS

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    I. V. Stepanov

    2017-01-01

    Full Text Available The processes of vital activity of cancer cells mainly depend on the production of growth factors and their receptors. The epidermal growth factor receptor (EGFR is a member of the ErbB family of receptor tyrosine kinases. Normally, binding of EGFR ligands and transforming growth factor alpha (TGFα induces receptor activation, which triggers erk and PI3K signaling pathways that control cell proliferation, migration, invasion and many other processes. A number of studies have shown that a high percentage of EGFR expression is observed in 25–82 % of cases with rectal cancer. Thus, the expression and mutation of the EGFR gene is associated with various variants of tumor progression and an unfavorable prognosis for malignant tumors of various localizations. The purpose of the study was to investigate the EGFR expression in cancer tissue and evaluate the relationship between EGFR expression and parameters of lymphogenous metastasis in patients with rectal cancer.  Material And Methods. Surgical specimens of 149 patients with stage T1–4N0–2M0, rectal adenocarcinoma, who were treated at the Cancer Research Institute of Tomsk National Research Medical Center, were studied using histological and immunohistochemical analyses. Positive EGFR expression was found in 88 (59.1 % patients. Diagnosis was made according to WHO classification (2010. Results. When studying the EGFR expression in tumor cells on different depth of invasion, it was found that the positive expression of this marker was observed in cases with and without lymph node metastases. The analysis of the EGFR expression in various structures of the parenchymatous component of the tumor located in different layers of the intestinal wall showed that in the solid structures of the mucosa, the positive expression of EGFR was detected more often in cases without lymph node metastases. In patients with lymph node metastases, the percentage of the EGFR expression was lower.  A similar pattern

  7. 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.

  8. The ethyl acetate fraction of Polytrichum commune L.ex Hedw induced cell apoptosis via reactive oxygen species in L1210 cells.

    Science.gov (United States)

    Cheng, Xiaoxia; Xiao, Yaping; Wang, Pan; Wang, Xiaobing; Zhou, Yuetao; Yan, Han; Liu, Quanhong

    2013-07-30

    Polytrichum commune L.ex Hedw is a traditional Chinese herb for treatment of fever, hemostatic, uterine prolapse and especially for leukemia. Previous studies indicated its anti-leukemia effect but the potential mechanisms have not been fully explained. The present study was further to investigate the underlying mechanism of ethyl acetate extract of Polytrichum commune L.ex Hedw (EEF)-induced toxicity and apoptosis in L1210 cells. Viability, DNA damage and apoptotic protein expressions of L1210 cells were analyzed by ViaCount, comet assay and western blot, respectively. At different times after EEF treatment, Bax redistribution in L1210 cells was examined using confocal microscopy; loss of mitochondrial membrane potential (MMP) was monitored by fluorescence microscope using rhodamine 123 staining; Intracellular reactive oxygen species (ROS) generation and DNA fragmentation were measured by flow cytometry using fluorescent dye, DCFH-DA and PI, respectively. EEF significantly inhibited L1210 cell survival, promoted Bax translocation onto mitochondria, stimulated caspase-9 activation and subsequent DNA damage in L1210 cells. Abundant ROS was detected in L1210 cells after EEF treatment, and the ROS scavenger NAC significantly relieved EEF-induced cell viability decline, MMP loss, and DNA fragmentation. EEF could induce mitochondria-dependent cell apoptosis in L1210 cells, and ROS may play an important role in this action. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  9. Hepatoprotective efficacy of Nigella sativa seeds dietary supplementation against lead acetate-induced oxidative damage in rabbit - Purification and characterization of glutathione peroxidase.

    Science.gov (United States)

    El-Far, Ali H; Korshom, Mahdy A; Mandour, Abdelwahab A; El-Bessoumy, Ashraf A; El-Sayed, Yasser S

    2017-03-03

    Lead (Pb) is a toxic ubiquitous environmental pollutant that induces hepatotoxicity in both animals and humans. The ability of Nigella saliva seeds (NSS) in ameliorating lead acetate (PbAc)-induced hepatic oxidative damage was investigated using a rabbit model. Forty New Zealand rabbits were given feed and water ad libitum. They were allocated randomly into four groups: control; PbAc (5g/L drinking water); NSS (20g/kg diet) and NSS+PbAc groups. After two months, liver samples were collected and analyzed for malondialdehyde (MDA), glutathione (GSH), glutathione S-transferase (GST) and glutathione peroxidase (GPx) contents. Purification and characterization of GPx were also evaluated. PbAc exposure significantly (pcumene hydroperoxide were 4.76μM in control, PbAc and NSS+PbAc groups, and 4.09μM in NSS group. The GPx reaction had a temperature optimum 40°C, pH optimum 8 and molecular weight 21 kDa. The obtained data indicated the potent efficacy of NSS against PbAc-induced oxidative stress; that was mediated through induction and activation of antioxidants, particularly GPx and scavenging free radicals. Moreover, the purified hepatic GPx is characterized as a selenoprotein (Se-GPx).

  10. Evidence for a solvent-induced change in rate-limiting step in the hydrolysis of benzaldehyde dimethyl acetal

    Energy Technology Data Exchange (ETDEWEB)

    Young, P.R.; Bogseth, R.C.; Rietz, E.G.

    1980-09-24

    Secondary deuterium isotope effects for the hydrolysis of the dimethyl acetal of benzaldehyde-formyl-d have been determined in mixed water-dioxane solvents varying between pure water and 70% dioxane, 30% water, by volume. Between 0 and 20% dioxane, the isotope effect (k/sup H//k/sup D/) decreases from 1.12 to 1.06. Between 20 and 70% added dioxane, the isotope effects increase regularly from 1.06 to 1.15. The decrease in the apparent isotope effect at low concentrations of dioxane may be an artifact of the biphasic kinetics observed due to hemiacetal buildup in the more aqueous media. The increases in k/sup H//k/sup D/ that are observed between 20 and 70% dioxane are interpreted in terms of a change in rate-limiting step from C-O bond cleavage in water to rate-limiting diffusion apart of the alcohol-oxocarbonium ion encounter pair in high concentrations of dioxane. On the basis of this assumption, ratios of the rate constants for internal return and diffusional separation of the complex are estimated. The steady decrease in rho and rho/sup r/ within the series water and 50 and 70% dioxane also suggests an increase in cationic character in the rate-limiting transition state. Isolated resonance structure-reactivity parameters (rho/sup r//rho/sub eq//sup r/) provide estimates of sp/sup 2/ character in rate-limiting transition states that are essentially identical with the estimates obtained from the secondary isotope effect studies.

  11. IL-17E synergizes with EGF and confers in vitro resistance to EGFR-targeted therapies in TNBC cells

    Science.gov (United States)

    Merrouche, Yacine; Fabre, Joseph; Cure, Herve; Garbar, Christian; Fuselier, Camille; Bastid, Jeremy; Antonicelli, Frank; Al-Daccak, Reem; Bensussan, Armand; Giustiniani, Jerome

    2016-01-01

    Estrogen receptor-, progesterone receptor- and HER2-negative breast cancers, also known as triple-negative breast cancers (TNBCs), have poor prognoses and are refractory to current therapeutic agents, including epidermal growth factor receptor (EGFR) inhibitors. Resistance to anti-EGFR therapeutic agents is often associated with sustained kinase phosphorylation, which promotes EGFR activation and translocation to the nucleus and prevents these agents from acting on their targets. The mechanisms underlying this resistance have not been fully elucidated. In addition, the IL-17E receptor is overexpressed in TNBC tumors and is associated with a poor prognosis. We have previously reported that IL-17E promotes TNBC resistance to anti-mitotic therapies. Here, we investigated whether IL-17E promotes TNBC resistance to anti-EGFR therapeutic agents by exploring the link between the IL-17E/IL-17E receptor axis and EGF signaling. We found that IL-17E, similarly to EGF, activates the EGFR in TNBC cells that are resistant to EGFR inhibitors. It also activates the PYK-2, Src and STAT3 kinases, which are essential for EGFR activation and nuclear translocation. IL-17E binds its specific receptor, IL-17RA/IL17RB, on these TNBC cells and synergizes with the EGF signaling pathway, thereby inducing Src-dependent EGFR transactivation and pSTAT3 and pEGFR translocation to the nucleus. Collectively, our data indicate that the IL-17E/IL-17E receptor axis may underlie TNBC resistance to EGFR inhibitors and suggest that inhibiting IL-17E or its receptor in combination with EGFR inhibitor administration may improve TNBC management. PMID:27462789

  12. Phorbol myristate acetate and Bryostatin 1 rescue IFN-gamma inducibility of MHC class II molecules in LS1034 colorectal carcinoma cell line

    Directory of Open Access Journals (Sweden)

    Wiseman Charles L

    2003-03-01

    Full Text Available Abstract Background The expression of major histocompatibility complex class II (MHCII antigens in both mouse and human tumors is rare, and these antigens are not easily inducible by IFN-gamma (IFNg. Since MHCII may play an important role in the development of host antitumor immune response, we explored the possibility of restoring MHCII inducibility in several IFNg-resistant tumor cell lines using protein kinase C (PKC agonists phorbol myristate acetate (PMA or Bryostatin. Results Tumor cells were co-cultured with various concentrations of PMA and IFNg for 48 hr. The expression of MHCII antigens and receptors IFNgR1 and IFNgR2 was determined by flow cytometry. We showed that the presence of as little as 0.1 ng/ml of PMA in tissue culture restored the ability of weakly inducible LS1034 colon carcinoma cells to express MHCII in response to IFNg (100 – 10,000 IU/ml in a dose-dependent manner. Likewise, Bryostatin 1, as low as 10 ng/ml produced a 5–6 fold upregulation of MHCII. The effect of PMA was not observed in two other poorly responding cell lines, MSTO-211H mesothelioma and HepG2 hepatocellular carcinoma, and was abrogated by relatively high concentrations of PKC inhibitors staurosporine (100 nM and GF 109203X (1,000 nM. Both surface and intracellular staining of all cell lines with antibodies against IFNgR1 and IFNgR2 failed to detect any increase in IFNg receptor expression following incubation with PMA. Conclusion In this study we showed that IFNg-inducibility of MHCII antigens in weakly inducible LS1034 colorectal carcinoma cell line can be rescued by concomitant incubation with PKC agonists. Bryostatin 1 may be considered for further investigation of IFNg-dependent MHCII induction in resistant tumors in vivo.

  13. Phorbol myristate acetate and Bryostatin 1 rescue IFN-gamma inducibility of MHC class II molecules in LS1034 colorectal carcinoma cell line

    Science.gov (United States)

    Kudinov, Yuri; Wiseman, Charles L; Kharazi, Alexander I

    2003-01-01

    Background The expression of major histocompatibility complex class II (MHCII) antigens in both mouse and human tumors is rare, and these antigens are not easily inducible by IFN-gamma (IFNg). Since MHCII may play an important role in the development of host antitumor immune response, we explored the possibility of restoring MHCII inducibility in several IFNg-resistant tumor cell lines using protein kinase C (PKC) agonists phorbol myristate acetate (PMA) or Bryostatin. Results Tumor cells were co-cultured with various concentrations of PMA and IFNg for 48 hr. The expression of MHCII antigens and receptors IFNgR1 and IFNgR2 was determined by flow cytometry. We showed that the presence of as little as 0.1 ng/ml of PMA in tissue culture restored the ability of weakly inducible LS1034 colon carcinoma cells to express MHCII in response to IFNg (100 – 10,000 IU/ml) in a dose-dependent manner. Likewise, Bryostatin 1, as low as 10 ng/ml produced a 5–6 fold upregulation of MHCII. The effect of PMA was not observed in two other poorly responding cell lines, MSTO-211H mesothelioma and HepG2 hepatocellular carcinoma, and was abrogated by relatively high concentrations of PKC inhibitors staurosporine (100 nM) and GF 109203X (1,000 nM). Both surface and intracellular staining of all cell lines with antibodies against IFNgR1 and IFNgR2 failed to detect any increase in IFNg receptor expression following incubation with PMA. Conclusion In this study we showed that IFNg-inducibility of MHCII antigens in weakly inducible LS1034 colorectal carcinoma cell line can be rescued by concomitant incubation with PKC agonists. Bryostatin 1 may be considered for further investigation of IFNg-dependent MHCII induction in resistant tumors in vivo. PMID:12787470

  14. 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 

  15. 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.

  16. Analgesic effect of Chinese herbal formula Hua-Jian-Ba-Du ointment on visceral pain in mice induced by acetic acid.

    Science.gov (United States)

    Ma, Shaojun; Zhang, Ying; Li, Xiaojiang; Zhang, He; Jia, Yingjie

    2015-05-01

    Visceral pain is one of the most important pains caused by cancer or other diseases, and most of the medications may lead to tolerance, addiction, and toxic side effects. Hua-Jian-Ba-Du Ointment (HJBDO), which is a commonly used conjugate based on traditional Chinese medicine theory, has been effective against visceral pain. Here, we verify the efficacy and underlying mechanism of HJBDO in an acetic-acid induced visceral pain model. Mice were subjected to acetic acid with or without HJBDO. Hua-Jian-Ba-Du Ointment at low (7.5 mL/kg•d), moderate (15 mL/kg•d), and high (30 mL/kg•d) dosages was applied on the abdomen, 3 times per day for 3 days. The acetic acid writhing test was used to evaluate antinociception. Interleukin-2 (IL-2) in serum, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and prostaglandin E2 (PGE2) in peritoneal fluid were detected by ELISA. 5-hydroxytryptamine (5-HT), norepinephrine (NE), dopamine (DA), and β-endorphin (β-EP) were examined by high performance liquid chromatography and radioimmunoassay, respectively. N-methyl-D-aspartic acid receptor (NMDAR1) and c-fos expressions in both rostral ventromedial medulla (RVM) and spinal dorsal horn were determined by western blot. Hua-Jian-Ba-Du Ointment at 3 dosage levels produced dose-dependent antinociception and shortened the latent time. Hua-Jian-Ba-Du Ointment at high or moderate dosage inhibited the release of TNF-α, IL-6, and PGE2, as well as increased the release of IL-2. Hua-Jian-Ba-Du Ointment could also increase NE and 5-HT contents and decrease the NE content. No effect of HJBDO at 3 dosages on the DA system was detected. Furthermore, HJBDO could suppress the expressions of NMDAR and c-fos in both RVM and spinal dorsal horn. Our results exhibited the analgesic effect of HJBDO on visceral pain in mice, and this effect might be mediated by the regulation of inflammation and neurotransmitters. © The Author(s) 2015.

  17. 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. Copyright © 2016 Elsevier

  18. Obtaining of inulin acetate

    OpenAIRE

    Khusenov, Arslonnazar; Rakhmanberdiev, Gappar; Rakhimov, Dilshod; Khalikov, Muzaffar

    2014-01-01

    In the article first obtained inulin ester inulin acetate, by etherification of inulin with acetic anhydride has been exposed. Obtained product has been studied using elementary analysis and IR spectroscopy.

  19. Role of IKK-alpha in the EGFR Signaling Regulation

    Science.gov (United States)

    2014-09-01

    activity elevates EGFR tyrosine phosphorylation. In addition, IKK forms a specific interaction with EGFR in Golgi apparatus and catalyzes EGFR S1026...colocalized in the Golgi apparatus upon EGF stimulation (Fig. S2B). To understand the underlying mechanism by which the inhibition of IKK results in EGFR

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Water-induced phase separation of miconazole-poly (vinylpyrrolidone-co-vinyl acetate) amorphous solid dispersions: Insights with confocal fluorescence microscopy.

    Science.gov (United States)

    Saboo, Sugandha; Taylor, Lynne S

    2017-08-30

    The aim of this study was to evaluate the utility of confocal fluorescence microscopy (CFM) to study the water-induced phase separation of miconazole-poly (vinylpyrrolidone-co-vinyl acetate) (mico-PVPVA) amorphous solid dispersions (ASDs), induced during preparation, upon storage at high relative humidity (RH) and during dissolution. Different fluorescent dyes were added to drug-polymer films and the location of the dyes was evaluated using CFM. Orthogonal techniques, in particular atomic force microscopy (AFM) coupled with nanoscale infrared spectroscopy (AFM-nanoIR), were used to provide additional analysis of the drug-polymer blends. The initial miscibility of mico-PVPVA ASDs prepared under low humidity conditions was confirmed by AFM-nanoIR. CFM enabled rapid identification of drug-rich and polymer-rich phases in phase separated films prepared under high humidity conditions. The identity of drug- and polymer-rich domains was confirmed using AFM-nanoIR imaging and localized IR spectroscopy, together with Lorentz contact resonance (LCR) measurements. The CFM technique was then utilized successfully to further investigate phase separation in mico-PVPVA films exposed to high RH storage and to visualize phase separation dynamics following film immersion in buffer. CFM is thus a promising new approach to study the phase behavior of ASDs, utilizing drug and polymer specific dyes to visualize the evolution of heterogeneity in films exposed to water. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. 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.

  7. 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.

    Science.gov (United States)

    Rahman, Shakilur; Ansari, Rizwan Ahmed; Rehman, Hasibur; Parvez, Suhel; Raisuddin, Sheikh

    2011-01-01

    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.

  8. Crotonis Fructus Extract Inhibits 12-O-Tetradecanoylphorbol-13-Acetate-Induced Expression of Matrix Metalloproteinase-9 via the Activator Protein-1 Pathway in MCF-7 Cells.

    Science.gov (United States)

    Song, Hyun-Kyung; Lee, Guem-San; Park, Sueng Hyuk; Noh, Eun-Mi; Kim, Jeong-Mi; Ryu, Do-Gon; Jung, Sung Hoo; Youn, Hyun Jo; Lee, Young-Rae; Kwon, Kang-Beom

    2017-09-01

    Metastatic cancers spread from the primary site of origin to other parts of the body. Matrix metalloproteinase-9 (MMP-9) is essential in metastatic cancers owing to its major role in cancer cell invasion. Crotonis fructus (CF), the mature fruits of Croton tiglium L., have been used for the treatment of gastrointestinal disturbance in Asia. In this study, the effect of the ethanol extract of CF (CFE) on MMP-9 activity and the invasion of 12-O-tetradecanoylphorbol-13-acetate (TPA)-treated MCF-7 cells was examined. The cell viability was evaluated using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The expression of MMP-9 was examined by Western blotting, zymography, and real-time polymerase chain reaction. An electrophoretic mobility gel shift assay was performed to detect activator protein-1 (AP-1) DNA binding activity and cell invasiveness was measured by an in vitro Matrigel invasion assay. CFE significantly suppressed MMP-9 expression and activation in a dose-dependent manner. Furthermore, CFE attenuated the TPA-induced activation of AP-1. The results indicated that the inhibitory effects of CFE against TPA-induced MMP-9 expression and MCF-7 cell invasion were dependent on the protein kinase C δ/p38/c-Jun N-terminal kinase/AP-1 pathway. Therefore, CFE could restrict breast cancer invasiveness owing to its ability to inhibit MMP-9 activity.

  9. Predominant contribution of syntrophic acetate oxidation to thermophilic methane formation at high acetate concentrations.

    Science.gov (United States)

    Hao, Li-Ping; Lü, Fan; He, Pin-Jing; Li, Lei; Shao, Li-Ming

    2011-01-15

    To quantify the contribution of syntrophic acetate oxidation to thermophilic anaerobic methanogenesis under the stressed condition induced by acidification, the methanogenic conversion process of 100 mmol/L acetate was monitored simultaneously by using isotopic tracing and selective inhibition techniques, supplemented with the analysis of unculturable microorganisms. Both quantitative methods demonstrated that, in the presence of aceticlastic and hydrogenotrophic methanogens, a large percentage of methane (up to 89%) was initially derived from CO(2) reduction, indicating the predominant contribution of the syntrophic acetate oxidation pathway to acetate degradation at high acid concentrations. A temporal decrease of the fraction of hydrogenotrophic methanogenesis from more than 60% to less than 40% reflected the gradual prevalence of the aceticlastic methanogenesis pathway along with the reduction of acetate. This apparent discrimination of acetate methanization pathways highlighted the importance of the syntrophic acetate-oxidizing bacteria to initialize methanogenesis from high organic loadings.

  10. 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...

  11. 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...

  12. 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.

  13. 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

  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. Cell adhesion and EGFR activation regulate EphA2 expression in cancer

    DEFF Research Database (Denmark)

    Larsen, Alice Bjerregaard; Stockhausen, Marie-Thérése; Poulsen, Hans Skovgaard

    2010-01-01

    . These effects were however abolished by activation of the EGF-receptor ligand system favoring Ras/MAPK signaling and cell proliferation. Based on our results, we propose a regulatory mechanism where cell adhesion induces EGFR kinase activation and EphA2 expression; and where the effect of ephrinA1 mediated...... largely unknown. Here we show that the expression of EphA2 in in vitro cultured cells, is restricted to cells growing adherently and that adhesion-induced EphA2 expression is dependent upon activation of the epidermal growth factor receptor (EGFR), mitogen activated protein kinase kinase (MEK) and Src...... family kinases (SRC). Moreover, the results show that adhesion-induced EGFR activation and EphA2 expression is affected by interactions with extracellular matrix (ECM) proteins working as integrin ligands. Stimulation with the EphA2 ligand, ephrinA1 inhibited ERK phosphorylation and cancer cell viability...

  16. 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.

  17. Luminescence properties of uranyl-acetate species

    Energy Technology Data Exchange (ETDEWEB)

    Brinkmann, Hannes; Moll, Henry [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Inst. of Resource Ecology; Stumpf, Thorsten [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biogeochemistry

    2017-06-01

    Time-resolved laser-induced fluorescence spectroscopy (TRLFS) was applied to characterize uranium(VI)- acetate species based on their luminescence properties. In contrast to previous interpretations, no indications were detected for the existence of the 1: 3 complex.

  18. NETUPITANT, A POTENT AND HIGHLY SELECTIVE NK1 RECEPTOR ANTAGONIST, ALLEVIATES ACETIC ACID-INDUCED BLADDER OVERACTIVITY IN ANESTHETIZED GUINEA-PIGS

    Directory of Open Access Journals (Sweden)

    Stefano Palea

    2016-08-01

    Full Text Available Introduction. Tachykinins potently contract the isolated urinary bladder from a number of animal species and play an important role in the regulation of the micturition reflex. On the guinea-pig isolated urinary bladder we examined the effects of a new potent and selective NK1 receptor antagonist (netupitant on the contractions induced by a selective NK1 receptor agonist, SP-methylester (SP-OMe. Moreover, the effects of netupitant and another selective NK1 antagonist (L-733,060 were studied in anesthetized guinea-pigs using two experimental models, the isovolumetric bladder contractions and a model of bladder overactivity induced by intravesical administration of acetic acid (AA. Methods and Results. Detrusor muscle strips were mounted in 5 mL organ baths and isometric contractions to cumulative concentrations of SP-OME were recorded before and after incubation with increasing concentrations of netupitant. In anesthetized female guinea-pigs, reflex bladder activity was examined under isovolumetric conditions with the bladder distended with saline or during cystometry using intravesical infusion of acetic acid (AA. After a 30 min stabilization period, netupitant (0.1-3 mg/kg, i.v. or L-733,060 (3-10 mg/kg, i.v. were administered. In the detrusor muscle, netupitant produced a concentration-dependent inhibition (mean pKB = 9.24 of the responses to SP-OMe. Under isovolumetric conditions, netupitant or L-733,060 reduced bladder contraction frequency in a dose-dependent manner, but neither drug changed bladder contraction amplitude. In the AA model, netupitant dose-dependently increased intercontraction interval (ICI but had no effect on the amplitude of micturition (AM. L-733,060 dose-dependently increased ICI also but this effect was paralleled by a significant reduction of AM. Conclusion. Netupitant decreases the frequency of reflex bladder contractions without altering their amplitude, suggesting that this drug targets the afferent limb of the

  19. Assessment of the antinociceptive effects of pregabalin alone or in combination with morphine during acetic acid-induced writhing in mice.

    Science.gov (United States)

    Shamsi Meymandi, Manzumeh; Keyhanfar, Fariborz

    2013-09-01

    Visceral pain currently represents one of the most important pain treatment challenges in clinical practice, and investigators across the world are continuously designing and conducting numerous studies in search of new analgesics and new combination therapies. The current study assessed the analgesic effects of saline, pregabalin (2, 5, 17, 50, 100, and 200 mg/kg, i.p.) and morphine (0.25, 0.5, 1, 3 and 5 mg/kg) alone or in combination on acetic-acid induced abdominal contractions in mice. The number of writhes and the inhibitory effects (as percentages, %E) were calculated as antinociception indexes. These indexes indicated that both pregabalin (Prg) and morphine (Mrp) produced dose-dependent antinociception. Pregabalin at 5 mg/kg (%E=32.5±4.0) or 2 mg/kg (%E=20.8±4.5) and morphine at 0.25 mg/kg (%E=20.2±7.8) and 0.5 mg/kg (%E=43.6±4.5) exhibited antinociceptive effects, and the combination of pregabalin and morphine produced significantly greater antinociceptive effects (%E=62.4±5.8 for Prg5+Mrp0.25; %E=71.7±4.8 for Prg5+Mrp0.5; and %E=54.1±4.0 for Prg2+Mrp0.25), although this enhancement was not observed when morphine was combined with 17 mg/kg pregabalin. Pre-treatment with 2 mg/kg (i.p.) naloxone did not affect increased analgesia when combined with these drugs. A dose-response curve was established for pregabalin at a fixed morphine dose and revealed that, at low doses, pregabalin dose-dependently enhanced the antinociceptive effects, while the opposite was true at high doses (17 and 25 mg/kg). In conclusion, pregabalin can produce levels of antinociception that are similar to those of morphine in acetic acid-induced viscero-somatic pain. The enhancement of antinociception produced by the co-administration of morphine and pregabalin is termed a supra-additive interaction and occurred at low doses but not at high doses. These findings militate for increased attention and caution in clinical settings.

  20. 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

  1. Glatiramer acetate (copaxone modulates platelet activation and inhibits thrombin-induced calcium influx: possible role of copaxone in targeting platelets during autoimmune neuroinflammation.

    Directory of Open Access Journals (Sweden)

    Sarah C Starossom

    Full Text Available BACKGROUND: Glatiramer acetate (GA, Copaxone, Copolymer-1 is an FDA approved drug for the treatment of MS and it is very effective in suppressing neuroinflammation in experimental autoimmune encephalitis (EAE, an animal model of MS. Although this drug was designed to inhibit pathogenic T cells, the exact mechanism of EAE/MS suppression by GA is still not well understood. Previously we presented evidence that platelets become activated and promote neuroinflammation in EAE, suggesting a possible pathogenic role of platelets in MS and EAE. We hypothesized that GA could inhibit neuroinflammation by affecting not only immune cells but also platelets. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the effect of GA on the activation of human platelets in vitro: calcium influx, platelet aggregation and expression of activation markers. Our results in human platelets were confirmed by in-vitro and in-vivo studies of modulation of functions of platelets in mouse model. We found that GA inhibited thrombin-induced calcium influx in human and mouse platelets. GA also decreased thrombin-induced CD31, CD62P, CD63, and active form of αIIbβ3 integrin surface expression and formation of platelet aggregates for both mouse and human platelets, and prolonged the bleeding time in mice by 2.7-fold. In addition, we found that GA decreased the extent of macrophage activation induced by co-culture of macrophages with platelets. CONCLUSIONS: GA inhibited the activation of platelets, which suggests a new mechanism of GA action in suppression of EAE/MS by targeting platelets and possibly preventing their interaction with immune cells such as macrophages. Furthermore, the reduction in platelet activation by GA may have additional cardiovascular benefits to prevent thrombosis.

  2. Nonlinear responses for chromosome and gene level effects induced by vinyl acetate monomer and its metabolite, acetaldehyde in TK6 cells.

    Science.gov (United States)

    Budinsky, Robert; Gollapudi, Bhaskar; Albertini, Richard J; Valentine, Rudolph; Stavanja, Mari; Teeguarden, Justin; Fensterheim, Robert; Rick, David; Lardie, Thomas; McFadden, Lisa; Green, Amanda; Recio, Leslie

    2013-12-01

    Vinyl acetate monomer (VAM) produced rat nasal tumors at concentrations in the hundreds of parts per million. However, VAM is weakly genotoxic in vitro and shows no genotoxicity in vivo. A European Union Risk Assessment concluded that VAM's hydrolysis to acetaldehyde (AA), via carboxylesterase, is a critical key event in VAM's carcinogenic potential. In the following study, we observed increases in micronuclei (MN) and thymidine kinase (Tk) mutants that were dependent on the ability of TK6 cell culture conditions to rapidly hydrolyze VAM to AA. Heat-inactivated horse serum demonstrated a high capacity to hydrolyze VAM to AA; this activity was highly correlated with a concomitant increase in MN. In contrast, heat-inactivated fetal bovine serum (FBS) did not hydrolyze VAM and no increase in MN was observed. AA's ability to induce MN was not impacted by either serum since it directly forms Schiff bases with DNA and proteins. Increased mutant frequency at the Tk locus was similarly mitigated when AA formation was not sufficiently rapid, such as incubating VAM in the presence of FBS for 4 hr. Interestingly, neither VAM nor AA induced mutations at the HPRT locus. Finally, cytotoxicity paralleled genotoxicity demonstrating that a small degree of cytotoxicity occurred prior to increases in MN. These results established 0.25 mM as a consistent concentration where genotoxicity first occurred for both VAM and AA provided VAM is hydrolyzed to AA. This information further informs significant key events related to the mode of action of VAM-induced nasal mucosal tumors in rats.

  3. 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

  4. Selective growth inhibition of human breast cancer cells by graviola fruit extract in vitro and in vivo involving downregulation of EGFR expression.

    Science.gov (United States)

    Dai, Yumin; Hogan, Shelly; Schmelz, Eva M; Ju, Young H; Canning, Corene; Zhou, Kequan

    2011-01-01

    The epidermal growth factor receptor (EGFR) is an oncogene frequently overexpressed in breast cancer (BC), and its overexpression has been associated with poor prognosis and drug resistance. EGFR is therefore a rational target for BC therapy development. This study demonstrated that a graviola fruit extract (GFE) significantly downregulated EGFR gene expression and inhibited the growth of BC cells and xenografts. GFE selectively inhibited the growth of EGFR-overexpressing human BC (MDA-MB-468) cells (IC(50) = 4.8 μg/ml) but had no effect on nontumorigenic human breast epithelial cells (MCF-10A). GFE significantly downregulated EGFR mRNA expression, arrested cell cycle in the G0/G1 phase, and induced apoptosis in MDA-MB-468 cells. In the mouse xenograft model, a 5-wk dietary treatment of GFE (200 mg/kg diet) significantly reduced the protein expression of EGFR, p-EGFR, and p-ERK in MDA-MB-468 tumors by 56%, 54%, and 32.5%, respectively. Overall, dietary GFE inhibited tumor growth, as measured by wet weight, by 32% (P < 0.01). These data showed that dietary GFE induced significant growth inhibition of MDA-MB-468 cells in vitro and in vivo through a mechanism involving the EGFR/ERK signaling pathway, suggesting that GFE may have a protective effect for women against EGFR-overexpressing BC.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Rapidly acquired resistance to EGFR tyrosine kinase inhibitors in NSCLC cell lines through de-repression of FGFR2 and FGFR3 expression.

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    Kathryn E Ware

    Full Text Available Despite initial and sometimes dramatic responses of specific NSCLC tumors to EGFR TKIs, nearly all will develop resistance and relapse. Gene expression analysis of NSCLC cell lines treated with the EGFR TKI, gefitinib, revealed increased levels of FGFR2 and FGFR3 mRNA. Analysis of gefitinib action on a larger panel of NSCLC cell lines verified that FGFR2 and FGFR3 expression is increased at the mRNA and protein level in NSCLC cell lines in which the EGFR is dominant for growth signaling, but not in cell lines where EGFR signaling is absent. A luciferase reporter containing 2.5 kilobases of fgfr2 5' flanking sequence was activated after gefitinib treatment, indicating transcriptional regulation as a contributing mechanism controlling increased FGFR2 expression. Induction of FGFR2 and FGFR3 protein as well as fgfr2-luc activity was also observed with Erbitux, an EGFR-specific monoclonal antibody. Moreover, inhibitors of c-Src and MEK stimulated fgfr2-luc activity to a similar degree as gefitinib, suggesting that these pathways may mediate EGFR-dependent repression of FGFR2 and FGFR3. Importantly, our studies demonstrate that EGFR TKI-induced FGFR2 and FGFR3 are capable of mediating FGF2 and FGF7 stimulated ERK activation as well as FGF-stimulated transformed growth in the setting of EGFR TKIs. In conclusion, this study highlights EGFR TKI-induced FGFR2 and FGFR3 signaling as a novel and rapid mechanism of acquired resistance to EGFR TKIs and suggests that treatment of NSCLC patients with combinations of EGFR and FGFR specific TKIs may be a strategy to enhance efficacy of single EGFR inhibitors.

  10. 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.

  11. Photolabile acetals as profragrances: the effect of structural modifications on the light-induced release of volatile aldehydes on cotton.

    Science.gov (United States)

    Trachsel, Alain; Buchs, Barbara; Herrmann, Andreas

    2016-09-31

    Because volatile compounds evaporate from surfaces that are usually exposed to daylight, photoresponsive delivery systems are particularly suitable to control their release. In the present study, we investigated 4,4-diphenyl-4H-benzo[d][1,3]dioxins as profragrances for the light-induced delivery of aldehydes in functional perfumery. The efficiency of fragrance release was investigated on cotton after direct and indirect surface deposition from a fabric softening formulation as a function of the substitution pattern of the profragrance structure. Dynamic headspace analysis above the cotton surface demonstrated that the structure of the profragrance had a much larger effect on the fragrance release than did the amount of deposition on the target surface. Although some trends observed for the photolysis in solution also applied to the reaction on cotton, it is not generally possible to predict the photochemical behaviour of structurally different precursors on surfaces from their solution properties. The fact that the present system performed on a dry surface makes it an interesting light-triggered delivery vehicle for other classes of bioactive volatile compounds, such as pheromones or agrochemicals.

  12. Manuka Honey Exerts Antioxidant and Anti-Inflammatory Activities That Promote Healing of Acetic Acid-Induced Gastric Ulcer in Rats

    Science.gov (United States)

    Almasaudi, Saad B.; Al-Hindi, Rashad R.; Abdel-dayem, Umama A.; Ali, Soad S.; Saleh, Rasha M.; Al Jaouni, Soad K.

    2017-01-01

    Gastric ulcers are a major problem worldwide with no effective treatment. The objective of this study was to evaluate the use of manuka honey in the treatment of acetic acid-induced chronic gastric ulcers in rats. Different groups of rats were treated with three different concentrations of honey. Stomachs were checked macroscopically for ulcerative lesions in the glandular mucosa and microscopically for histopathological alterations. Treatment with manuka honey significantly reduced the ulcer index and maintained the glycoprotein content. It also reduced the mucosal myeloperoxidase activity, lipid peroxidation (MDA), and the inflammatory cytokines (TNF-α, IL-1β, and IL-6) as compared to untreated control group. In addition, honey-treated groups showed significant increase in enzymatic (GPx and SOD) and nonenzymatic (GSH) antioxidants besides levels of the anti-inflammatory cytokine IL-10. Flow cytometry studies showed that treatment of animals with manuka honey has normalized cell cycle distribution and significantly lowered apoptosis in gastric mucosa. In conclusion, the results indicated that manuka honey is effective in the treatment of chronic ulcer and preservation of mucosal glycoproteins. Its effects are due to its antioxidant and anti-inflammatory properties that resulted in a significant reduction of the gastric mucosal MDA, TNF-α, IL-1β, and IL-6 and caused an elevation in IL-10 levels. PMID:28250794

  13. 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.

  14. 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

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

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    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

  16. Comparison of the anti-ulcer activity between the crude and bran-processed Atractylodes lancea in the rat model of gastric ulcer induced by acetic acid.

    Science.gov (United States)

    Yu, Yan; Jia, Tian-Zhu; Cai, Qian; Jiang, Ning; Ma, Ming-Yue; Min, Dong-Yu; Yuan, Yuan

    2015-02-03

    The rhizome of Atractylodes lancea (AL, Compositae, Chinese name: Cangzhu; Japanese name: Sou-ju-tsu) has been used traditionally for the treatment of various diseases such as digestive disorders, rheumatic diseases, and influenza in China, Korea and Japan. The crude AL and AL bran-processed are both listed in the Chinese Pharmacopoeia. However, the differences between the effects of the crude and AL bran-processed on gastric ulcer were poorly understood, and the mechanisms for the treatment of gastric ulcer were not clear. This study aimed at comparing the anti-ulcer effects between the crude AL and AL processed in acetic acid induced model in rats and evaluating the mechanisms of action involved in the anti-ulcer properties of AL. The model of gastric ulcer was imitated by acetic acid in rats, and AL was gavaged. The serum and gastric tissues were collected. The levels of epidermal growth factor (EGF), trefoil factor2 (TFF2), tumor necrosis factor-α (TNF-α), interleukin 6, 8 (IL-6, 8) and prostaglandin E2 (PGE2) in serum and gastric tissues were determined by the double-antibody sandwich enzyme-linked immunosorbent assay (ELISA), and the mRNA expressions of EGF, TFF2, TNF-α, and IL-8 in stomach were analyzed by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR). Meanwhile, histopathological changes were evaluated by hematoxylin and eosin (HE) stain. The protein expressions of EGF, TFF2, TNF-α, and IL-8 were examined by immunohistochemistry in stomach. The results demonstrated that the damage of gastric tissue was obviously alleviated and the productions of TNF-α, IL-8, IL-6, and PGE2 and the mRNA expressions of TNF-α, and IL-8 were notably inhibited. Furthermore, the productions of EGF and TFF2 and the mRNA expressions of EGF and TFF2 were significantly stimulated by both crude AL and AL processed in a dose-dependent manner. Compared with the crude AL, the processed AL was more effective. The AL processed had more satisfactory

  17. 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.

  18. 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.

  19. Rose Bengal acetate photodynamic therapy (RBAc-PDT) induces exposure and release of Damage-Associated Molecular Patterns (DAMPs) in human HeLa cells.

    Science.gov (United States)

    Panzarini, Elisa; Inguscio, Valentina; Fimia, Gian Maria; Dini, Luciana

    2014-01-01

    The new concept of Immunogenic Cell Death (ICD), associated with Damage Associated Molecular Patterns (DAMPs) exposure and/or release, is recently becoming very appealing in cancer treatment. In this context, PhotoDynamic Therapy (PDT) can give rise to ICD and to immune response upon dead cells removal. The list of PhotoSensitizers (PSs) able to induce ICD is still short and includes Photofrin, Hypericin, Foscan and 5-ALA. The goal of the present work was to investigate if Rose Bengal Acetate (RBAc), a powerful PS able to trigger apoptosis and autophagy, enables photosensitized HeLa cells to expose and/or release pivotal DAMPs, i.e. ATP, HSP70, HSP90, HMGB1, and calreticulin (CRT), that characterize ICD. We found that apoptotic HeLa cells after RBAc-PDT exposed and released, early after the treatment, high amount of ATP, HSP70, HSP90 and CRT; the latter was distributed on the cell surface as uneven patches and co-exposed with ERp57. Conversely, autophagic HeLa cells after RBAc-PDT exposed and released HSP70, HSP90 but not CRT and ATP. Exposure and release of HSP70 and HSP90 were always higher on apoptotic than on autophagic cells. HMGB1 was released concomitantly to secondary necrosis (24 h after RBAc-PDT). Phagocytosis assay suggests that CRT is involved in removal of RBAc-PDT generated apoptotic HeLa cells. Altogether, our data suggest that RBAc has all the prerequisites (i.e. exposure and/or release of ATP, CRT, HSP70 and HSP90), that must be verified in future vaccination experiments, to be considered a good PS candidate to ignite ICD. We also showed tha CRT is involved in the clearance of RBAc photokilled HeLa cells. Interestingly, RBAc-PDT is the first cancer PDT protocol able to induce the translocation of HSP90 and plasma membrane co-exposure of CRT with ERp57.

  20. Ethyl acetate fraction of Cissus quadrangularis stem ameliorates hyperglycaemia-mediated oxidative stress and suppresses inflammatory response in nicotinamide/streptozotocin induced type 2 diabetic rats.

    Science.gov (United States)

    Lekshmi, R K; Rajesh, R; Mini, S

    2015-09-15

    Cissus quadrangularis is a plant with great medicinal value and different parts of the plant is traditionally used for the treatment of skin infections, constipation, piles, anaemia, asthma, irregular menstruation, burns and wounds. The stems and leaves of Cissus quadrangularis has been traditionally consumed as a vegetable. The current study was hypothesized to investigate the beneficial effects of ethyl acetate fraction of Cissus quadrangularis stem (CQSF) on hyperglycaemia-mediated oxidative stress and inflammatory responses in nicotinamide/streptozotocin induced diabetes mellitus. Experimental diabetes was induced by intraperitoneal injection of 110 mg/kg body weight nicotinamide 15 min prior to the injection of 45 mg/kg body weight streptozotocin. Diabetic rats were administered with a daily oral dose of 100 mg/kg CQSF for 60 days after diabetes induction. Diabetic control rats showed significant (p < 0.05) increase in blood glucose, HbA1c, liver toxicity markers, inflammatory markers and lipid peroxidation products and reduction in the activities of antioxidant enzymes. The mRNA expressions of TNF-α, IL-6 and NF-κB in adipose tissue were significantly (p < 0.05) increased in diabetic group. Nuclear translocation of NF-κB p65 subunit level was greater in diabetic rats. CQSF administration significantly reversed these alterations. Histopathological alterations of liver and pancreas were also restored by CQSF treatment. The results were compared with the standard oral hypoglycaemic drug metformin. In addition, the ESI-MS and GC-MS analysis of CQSF confirmed the presence of quercetin and phenol, 2,4-bis(1,1-dimethylethyl)- respectively. The present study demonstrates that CQSF exerts antidiabetic activity by potentiating the antioxidant defense system and suppressing inflammatory responses. Copyright © 2015 Elsevier GmbH. All rights reserved.

  1. Comparison of the therapeutic effects of sildenafil citrate, heparin and neuropeptides in a rat model of acetic acid-induced gastric ulcer.

    Science.gov (United States)

    Kalayci, Mehmet; Kocdor, Mehmet Ali; Kuloglu, Tuncay; Sahin, İbrahim; Sarac, Mehmet; Aksoy, Aziz; Yardim, Meltem; Dalkilic, Semih; Gursu, Onur; Aydin, Suna; Akkoc, Ramazan Fazil; Ugras, Meltem; Artas, Gokhan; Ozercan, İbrahim Hanifi; Ugur, Kader; Aydin, Suleyman

    2017-10-01

    The purpose of our investigative work has been to determine whether there can be therapeutic roles in the administration of sildenafil citrate, heparin and several neuropeptides on an animal model where gastric ulcers were induced with acetic acid, and to compare their efficacy. The animals were divided into 13 groups, with 4 animals in each. Gastric ulcers was induced in the animals of 12 groups with one untreated group being left as the control (Group I - control; given normal saline (NS)). The other groups were: Group II (ulcer+NS); Group III (5mg/kg sildenafil citrate, low dose); Group IV (10mg/kg sildenafil citrate, high dose); Group V (0.6mg/kg heparin, low dose); Group VI (6mg/kg heparin, high dose); Group VII (20nmol/kg des-acyl ghrelin); Group VIII (40nmol/kg des-acyl ghrelin); Group IX (4nmol/kg acyl ghrelin); Group X (8nmol/kg acly ghrelin); Group XI (20pmol/kg Nesfatin-1); Group XII (15nmol/kg Obestatin) and Group XIII (5nmol/kg Neuropeptide Y). Gastric neuropeptide expression was measured using an immunohistochemical method, and the amount in circulation was detected using ELISA. To compare with no treatment, the controls and other treatment groups, we recorded loss of the surface epithelium of the stomach, erosion, bleeding and inflammatory cell infiltration in the upper halves of the gastric glands. The muscularis and the layers beneath it were, however, apparently normal. The gastric mucosa healed with little or no inflammation when sildenafil citrate, low dose heparin, ghrelin, NUCB2/Nesfatin-1, obestatin, Neuropeptide Y were administered. Overall the data indicate that low dose heparin, and especially sildenafil citrate and neuropeptides, can be used clinically as an alternative approach in the treatment of the gastric ulcer. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Kaempferol inhibits cell proliferation and glycolysis in esophagus squamous cell carcinoma via targeting EGFR signaling pathway.

    Science.gov (United States)

    Yao, Shihua; Wang, Xiaowei; Li, Chunguang; Zhao, Tiejun; Jin, Hai; Fang, Wentao

    2016-08-01

    Antitumor activity of kaempferol has been studied in various tumor types, but its potency in esophagus squamous cell carcinoma is rarely known. Here, we reported the activity of kaempferol against esophagus squamous cell carcinoma as well as its antitumor mechanisms. Results of cell proliferation and colony formation assay showed that kaempferol substantially inhibited tumor cell proliferation and clone formation in vitro. Flow cytometric analysis demonstrated that tumor cells were induced G0/G1 phase arrest after kaempferol treatment, and the expression of protein involved in cell cycle regulation was dramatically changed. Except the potency on cell proliferation, we also discovered that kaempferol had a significant inhibitory effect against tumor glycolysis. With the downregulation of hexokinase-2, glucose uptake and lactate production in tumor cells were dramatically declined. Mechanism studies revealed kaempferol had a direct effect on epidermal growth factor receptor (EGFR) activity, and along with the inhibition of EGFR, its downstream signaling pathways were also markedly suppressed. Further investigations found that exogenous overexpression of EGFR in tumor cells substantially attenuated glycolysis suppression induced by kaempferol, which implied that EGFR also played an important role in kaempferol-mediated glycolysis inhibition. Finally, the antitumor activity of kaempferol was validated in xenograft model and kaempferol prominently restrained tumor growth in vivo. Meanwhile, dramatic decrease of EGFR activity and hexokinase-2 expression were observed in kaempferol-treated tumor tissue, which confirmed these findings in vitro. Briefly, these studies suggested that kaempferol, or its analogues, may serve as effective candidates for esophagus squamous cell carcinoma management.

  3. Differential effect of EGFR inhibitors on tamoxifen-resistant breast cancer cells.

    Science.gov (United States)

    Kim, Sangmin; Lee, Jeongmin; Oh, Soo Jin; Nam, Seok Jin; Lee, Jeong Eon

    2015-09-01

    Although tamoxifen is the most common and effective therapy for treatment of estrogen receptor-α (ER-α) breast cancer patients, resistance of endocrine therapy occurs, either de novo or acquired during therapy. Here, we investigated the clinical value of epidermal growth factor receptor (EGFR) in tamoxifen-resistant (TamR) patients and the differential effect of EGFR inhibitors, neratinib and gefitinib, on TamR breast cancer cell model. The morphology of TamR MCF7 cells showed mesenchymal phenotypes and did not induce cell death by tamoxifen treatment compared with tamoxifen‑sensitive (TamS) MCF7 cells. In addition, mesenchymal marker proteins, including N-cadherin (N-cad), fibronectin (FN), and Slug, significantly increased in TamR cells. In contrast, ER-α and E-cadherin (E-cad) were greatly decreased. We also found that the levels of EGFR and HER2 expression were increased in TamR cells. Furthermore, we observed that EGFR expression was directly involved with poor prognosis of tamoxifen-treated breast cancer patients using the GSE1378 date set. Thus, we treated TamR and TamS cells with EGFR inhibitors, neratinib and gefitinib, respectively. Interestingly, neratinib induced apoptotic cell death of TamR but not gefitinib. Cleaved PARP-1 expression was also increased by neratinib treatment in TamR cells. Therefore, we suggest that neratinib may be a potential therapeutic drug for treating TamR breast cancer.

  4. Histone Deacetylase 3 Inhibition Overcomes BIM Deletion Polymorphism-Mediated Osimertinib Resistance in EGFR-Mutant Lung Cancer.

    Science.gov (United States)

    Tanimoto, Azusa; Takeuchi, Shinji; Arai, Sachiko; Fukuda, Koji; Yamada, Tadaaki; Roca, Xavier; Ong, S Tiong; Yano, Seiji

    2016-12-16

    Purpose: The BIM deletion polymorphism is associated with apoptosis resistance to EGFR tyrosine kinase inhibitors (EGFR-TKI), such as gefitinib and erlotinib, in non-small cell lung cancer (NSCLC) harboring EGFR mutations. Here, we investigated whether the BIM deletion polymorphism contributes to resistance against osimertinib, a third-generation EGFR-TKI. In addition, we determined the efficacy of a histone deacetylase (HDAC) inhibitor, vorinostat, against this form of resistance and elucidated the underlying mechanism.Experimental Design: We used EGFR-mutated NSCLC cell lines, which were either heterozygous or homozygous for the BIM deletion polymorphism, to evaluate the effect of osimertinib in vitro and in vivo Protein expression was examined by Western blotting. Alternative splicing of BIM mRNA was analyzed by RT-PCR.Results:EGFR-mutated NSCLC cell lines with the BIM deletion polymorphism exhibited apoptosis resistance to osimertinib in a polymorphism dosage-dependent manner, and this resistance was overcome by combined use with vorinostat. Experiments with homozygous BIM deletion-positive cells revealed that vorinostat affected the alternative splicing of BIM mRNA in the deletion allele, increased the expression of active BIM protein, and thereby induced apoptosis in osimertinib-treated cells. These effects were mediated predominantly by HDAC3 inhibition. In xenograft models, combined use of vorinostat with osimertinib could regress tumors in EGFR-mutated NSCLC cells homozygous for the BIM deletion polymorphism. Moreover, this combination could induce apoptosis even when tumor cells acquired EGFR-T790M mutations.Conclusions: These findings indicate the importance of developing HDAC3-selective inhibitors, and their combined use with osimertinib, for treating EGFR-mutated lung cancers carrying the BIM deletion polymorphism. Clin Cancer Res; 1-11. ©2016 AACR.

  5. 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

  6. 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.

  7. Interrogation of EGFR Targeted Uptake of TiO2 Nanoconjugates by X-ray Fluorescence Microscopy

    Science.gov (United States)

    Yuan, Ye; Paunesku, Tatjana; Arora, Hans; Ward, Jesse; Vogt, Stefan; Woloschak, Gayle

    2013-01-01

    We are developing TiO2 nanoconjugates that can be used as therapeutic and diagnostic agents. Nanoscale TiO2 can be surface conjugated with various molecules and has the unique ability to induce the production of reactive oxygen species after radiation activation. One way to improve the potential clinical usefulness of TiO2 nanoparticles is to control their delivery to malignant cells by targeting them to cancer cell specific antigens. Epidermal Growth Factor Receptor is one potential target that is enriched in epithelial cancers and is rapidly internalized after ligand binding. Hence, we have synthesized TiO2 nanoparticles and functionalized them with a short EGFR binding peptide to create EGFR-targeted NCs. X-ray Fluorescence Microscopy was used to image nanoconjugates within EGFR positive HeLa cells. Further labeling of fixed cells with antibodies against EGFR and Protein A nanogold showed that TiO2 nanoconjugates can colocalize with receptors at the cell’s plasma membrane. Interestingly, with increased incubation times, EGFR targeted nanoconjugates could also be found colocalized with EGFR within the cell nucleus. This suggests that EGFR-targeted nanoconjugates can bind the receptor at the cell membrane, which leads to the internalization of NC-receptor complexes and the subsequent transport of nanoconjugates into the nucleus. PMID:25284907

  8. 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.

  9. 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.

  10. 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

  11. Phorbol 12-myristate 13-acetate-induced endocytosis of the Na-K-2Cl cotransporter in MDCK cells is associated with a clathrin-dependent pathway.

    Science.gov (United States)

    Mykoniatis, Andreas; Shen, Le; Fedor-Chaiken, Mary; Tang, Jun; Tang, Xu; Worrell, Roger T; Delpire, Eric; Turner, Jerrold R; Matlin, Karl S; Bouyer, Patrice; Matthews, Jeffrey B

    2010-01-01

    In secretory epithelial cells, the basolateral Na(+)-K(+)-2Cl(-) cotransporter (NKCC1) plays a major role in salt and fluid secretion. Our laboratory has identified NKCC1 surface expression as an important regulatory mechanism for Cl(-) secretion in the colonic crypt cell line T84, a process also present in native human colonic crypts. We previously showed that activation of protein kinase C (PKC) by carbachol and phorbol 12-myristate 13-acetate (PMA) decreases NKCC1 surface expression in T84 cells. However, the specific endocytic entry pathway has not been defined. We used a Madin-Darby canine kidney (MDCK) cell line stably transfected with enhanced green fluorescent protein (EGFP)-NKCC1 to map NKCC1 entry during PMA exposure. At given times, we fixed and stained the cells with specific markers (e.g., dynamin II, clathrin heavy chain, and caveolin-1). We also used chlorpromazine, methyl-beta-cyclodextrin, amiloride, and dynasore, blockers of the clathrin, caveolin, and macropinocytosis pathways and the vesicle "pinchase" dynamin, respectively. We found that PMA caused dose- and time-dependent NKCC1 endocytosis. After 2.5 min of PMA exposure, approximately 80% of EGFP-NKCC1 endocytic vesicles colocalized with clathrin and approximately 40% colocalized with dynamin II and with the transferrin receptor, the uptake of which is also mediated by clathrin-coated vesicles. We did not observe significant colocalization of EGFP-NKCC1 endocytic vesicles with caveolin-1, a marker of the caveolae-mediated endocytic pathway. We quantified the effect of each inhibitor on PMA-induced EGFP-NKCC1 endocytosis and found that only chlorpromazine and dynasore caused significant inhibition compared with the untreated control (61% and 25%, respectively, at 2.5 min). Together, these results strongly support the conclusion that PMA-stimulated NKCC1 endocytosis is associated with a clathrin pathway.

  12. Epibrassinolide induces changes in indole-3-acetic acid, abscisic acid and polyamine concentrations and enhances antioxidant potential of radish seedlings under copper stress.

    Science.gov (United States)

    Choudhary, Sikander Pal; Bhardwaj, Renu; Gupta, Bishan Datt; Dutt, Prabhu; Gupta, Rajinder Kumar; Biondi, Stefania; Kanwar, Mukesh

    2010-11-01

    In the present study, the effects of epibrassinolide (EBL) on indole-3-acetic acid (IAA), abscisic acid (ABA) and polyamine (PA) tissue concentrations and antioxidant potential of 7-day-old Raphanus sativus L. cv. 'Pusa chetki' seedlings grown under Cu stress were investigated. EBL treatment alone or in combination with Cu enhanced free and bound IAA titers when compared with the metal alone. Modest increases in free and bound ABA contents were observed for EBL treatment alone. However, the combination of EBL with Cu caused major increases in both forms of ABA, over Cu alone. Among the PAs analyzed, only putrescine and cadaverine concentrations were enhanced by EBL treatment alone. By contrast, a significant decline in putrescine and spermine contents was found in seedlings treated with EBL plus Cu. EBL treatments alone or in combination with Cu enhanced activities of guaiacol peroxidase (EC1.11.1.7), catalase (EC 1.11.1.6), superoxide dismutase (EC 1.15.1.1) and glutathione reductase (EC 1.6.4.2) and protein contents in comparison with metal and control treatments. A major decrease in malondialdehyde content was also recorded for EBL treatments with or without Cu. An increase in phytochelatin content was also observed in seedlings treated with EBL alone or in combination with Cu. Major improvement in radical scavenging activities, as attested by the antioxidant activity assay using DPPH (1,1-diphenylpicrylhydrazyl), and elevated deoxyribose and reducing powers, along with increased contents of ascorbic acid, total phenols and proline, also suggest a major influence of EBL application in mitigating copper-induced oxidative stress in radish seedlings. Copyright © Physiologia Plantarum 2010.

  13. Synergistic Antitumor Effect between Gefitinib and Fractionated Irradiation in Anaplastic Oligodendrogliomas Cannot Be Predicted by the Egfr Signaling Activity

    Science.gov (United States)

    Pinel, Sophie; Mriouah, Jihane; Vandamme, Marc; Chateau, Alicia; Plénat, François; Guérin, Eric; Taillandier, Luc; Bernier-Chastagner, Valérie; Merlin, Jean-Louis; Chastagner, Pascal

    2013-01-01

    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. PMID:23874590

  14. 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.

  15. Targeting the EGFR pathway for cancer therapy

    DEFF Research Database (Denmark)

    Johnston, JB; Navaratnam, S; Pitz, MW

    2006-01-01

    provided the rationale for the targeting of the components of the EGFR signaling pathways for cancer therapy. Below we discuss various aspects of EGFR-targeted therapies mainly in hematologic malignancies, lung cancer and breast cancer. Beside novel therapeutic approaches, we also discuss specific side......Clinical studies have shown that HER-2/Neu is over-expressed in up to one-third of patients with a variety of cancers, including B-cell acute lymphoblastic leukemia (B-ALL), breast cancer and lung cancer, and that these patients are frequently resistant to conventional chemo-therapies. Additionally...... effects associated with the therapeutic inhibition of components of the EGFR-pathways. Alongside small inhibitors, such as Lapatinib (Tykerb, GW572016), Gefitinib (Iressa, ZD1839), and Erlotinib (Tarceva, OSI-774), a significant part of the review is also dedicated to therapeutic antibodies (e...

  16. Conditional Inactivation of Pten with EGFR Overexpression in Schwann Cells Models Sporadic MPNST

    Directory of Open Access Journals (Sweden)

    Vincent W. Keng

    2012-01-01

    Full Text Available The genetic mechanisms involved in the transformation from a benign neurofibroma to a malignant sarcoma in patients with neurofibromatosis-type-1- (NF1-associated or sporadic malignant peripheral nerve sheath tumors (MPNSTs remain unclear. It is hypothesized that many genetic changes are involved in transformation. Recently, it has been shown that both phosphatase and tensin homolog (PTEN and epidermal growth factor receptor (EGFR play important roles in the initiation of peripheral nerve sheath tumors (PNSTs. In human MPNSTs, PTEN expression is often reduced, while EGFR expression is often induced. We tested if these two genes cooperate in the evolution of PNSTs. Transgenic mice were generated carrying conditional floxed alleles of Pten, and EGFR was expressed under the control of the 2′,3′-cyclic nucleotide 3′phosphodiesterase (Cnp promoter and a desert hedgehog (Dhh regulatory element driving Cre recombinase transgenic mice (Dhh-Cre. Complete loss of Pten and EGFR overexpression in Schwann cells led to the development of high-grade PNSTs. In vitro experiments using immortalized human Schwann cells demonstrated that loss of PTEN and overexpression of EGFR cooperate to increase cellular proliferation and anchorage-independent colony formation. This mouse model can rapidly recapitulate PNST onset and progression to high-grade PNSTs, as seen in sporadic MPNST patients.

  17. 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.

  18. 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

  19. 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

  20. Inhibition of 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse skin ornithine decarboxylase and protein kinase C by polyphenolics from grapes.

    Science.gov (United States)

    Bomser, J; Singletary, K; Meline, B

    2000-06-15

    Ornithine decarboxylase is the rate-limiting enzyme in the biosynthesis of polyamines, which are believed to play an essential role in diverse biological processes including cell proliferation and differentiation. We have previously reported [J. Bomser, K. Singletary, M. Wallig, M. Smith, Inhibition of TPA-induced tumor promotion in CD-1 mouse epidermis by a polyphenolic fraction from grape seeds, Cancer Letters 135 (1999) 151-157] that pre-application of a grape polyphenolic fraction (GPF) to mouse skin epidermis inhibits 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ornithine decarboxylase (ODC) activity, as well as 7, 12-dimethylbenz[a]anthracene (DMBA)-initiated, TPA-promoted mouse skin tumorigenesis. The present studies were designed to further characterize the effect of time and dose of application of GPF on TPA-induced ODC activity and protein expression, and on protein kinase C activity in mouse skin epidermis. In addition, the effect of GPF on ODC kinetics in vitro was examined. Application of 5, 10, and 20 mg of GPF 20 min prior to treatment with TPA resulted in a significant decrease in epidermal ODC activity of 54, 53, 90%, respectively, compared with controls. Yet, ODC protein levels (Western blot) in the 10 and 20 mg GPF groups were significantly increased by 1.8 and 1.9-fold, respectively, compared with controls. A similar response was observed with the ODC inhibitor 2-difluoromethylornithine (DFMO), which served as a positive control. Application of grape polyphenolics (20 mg) at 60 and 30 min prior to treatment with TPA inhibited ODC activity by 62 and 68%, respectively, compared with controls (Pgrape polyphenolics (20 mg) at 60, 120 and 240 min after treatment with TPA resulted in no significant changes in ODC activity. A similar increase in epidermal ODC protein was observed in these GPF-treated animals, similar to that observed when GPF application preceded TPA. When applied to mouse skin prior to TPA, GPF was associated with a decrease in

  1. Management of Toxicities in Metastatic NSCLC Related to Anti-Lung Cancer Therapies with EGFR-TKIs

    Directory of Open Access Journals (Sweden)

    Barbara eMelosky

    2014-09-01

    Full Text Available Tyrosine kinase inhibitors (TKIs against the epidermal growth factor receptor (EGFR are the standard of care treatment in non-small cell lung cancer (NSCLC. TKIs are used first line in EGFR mutation-positive NSCLC; erlotinib is the only TKI approved for subsequent lines of treatment in EGFR wild-type NSCLC. As promising as TKIs are in helping patients avoid some of the side effects of traditional cytotoxic chemotherapy, they do come with a variety of side effects.This article will describe the most common adverse events associated with the epidermal EGFR family of TKIs including diarrhea, rash, mucositis, and paronychia. The objective of this paper is to provide simple guidelines to assist oncologists in managing these common toxicities. As patient survival is often directly correlated with successful therapeutic drug delivery, the management of TKI- induced adverse events ensures proper treatment and may avoid discontinuation or reduction of the therapeutic.

  2. Diesel exhaust increases EGFR and phosphorylated C-terminal Tyr 1173 in the bronchial epithelium

    Directory of Open Access Journals (Sweden)

    Wilson Susan J

    2008-05-01

    Full Text Available Abstract Background Epidemiological studies have demonstrated adverse health effects of environmental pollution. Diesel exhaust (DE is a major contributor to particulate matter pollution. DE exposure has been shown to induce a pronounced inflammatory response in the airways, together with an enhanced epithelial expression of cytokines such as IL-8, Gro-α, IL-13 and activation of redox sensitive transcription factors (NFκB, AP-1, and MAP kinases (p38, JNK. The aim of the present investigation was to elucidate the involvement of the epidermal growth factor receptor (EGFR signalling pathway in the epithelial response to DE in-vivo. Results Immunohistochemical staining was used to quantify the expression of the EGFR, phosphorylated Tyrosine residues, MEK and ERK in the bronchial epithelium of archived biopsies from 15 healthy subjects following exposure to DE (PM10, 300 μg/m3 and air. DE induced a significant increases in the expression of EGFR (p = 0.004 and phosphorylated C-terminal Tyr 1173 (p = 0.02. Other investigated EGFR tyrosine residues, Src related tyrosine (Tyr 416, MEK and ERK pathway were not changed significantly by DE. Conclusion Exposure to DE (PM10, 300 μg/m3 caused enhanced EGFR expression and phosphorylation of the tyrosine residue (Tyr 1173 which is in accordance with the previously demonstrated activation of the JNK, AP-1, p38 MAPK and NFkB pathways and associated downstream signalling and cytokine production. No effects were seen on the MEK and ERK pathway suggesting that at the investigated time point (6 hours post exposure there was no proliferative/differentiation signalling in the bronchial epithelium. The present findings suggest a key role for EGFR in the bronchial response to diesel exhaust.

  3. 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.

  4. 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.

  5. Ferulic Acid Protects Against Lead Acetate-Induced Inhibition of Neurite Outgrowth by Upregulating HO-1 in PC12 Cells: Involvement of ERK1/2-Nrf2 Pathway.

    Science.gov (United States)

    Yu, Chun-Lei; Zhao, Xue-Mei; Niu, Ying-Cai

    2016-11-01

    Prenatal lead exposure is associated with poor intellectual development in children. However, there are few breakthroughs in therapeutic intervention of developmental lead neurotoxicity. The aim of this study is to evaluate the hypothesis that ferulic acid-mediated promotion of neurite outgrowth following lead exposure might mainly result from its antioxidant capability by extracellular signal-regulated kinases 1 and 2 (ERK1/2) activation of nuclear factor erythroid 2-related factor 2 (Nrf2). Exposure of PC12 cells to lead acetate inhibits neurite outgrowth and causes oxidative stress as measured by ROS, LPO, GSH/GSSG, and NAD(+)/NADH. FA treatment significantly, although not completely, protected the cells against lead acetate-induced neurite outgrowth inhibition. The effects of FA could be blocked by PD98059, zinc protoporphyrin (Zn-PP), and Nrf2 shRNA. In addition, FA induced heme oxygenase 1 (HO-1) gene expression, enhanced antioxidant response element (ARE) promoter activity, promoted ERK1/2 phosphorylation, and Nrf2 translocation in PC12 cells exposed to lead acetate. ERK1/2 locate upstream of Nrf2 and regulate Nrf2-dependent HO-1 expression in antioxidative effects of FA. Our results suggest that FA is a promising candidate for treatment of developmental lead neurotoxicity. These promising findings warrant future investigation evaluating the FA-mediated potentiation of neurite outgrowth following lead exposure in vivo.

  6. Synergistic cytotoxicity of afatinib and cetuximab against EGFR T790M involves Rab11-dependent EGFR recycling.

    Science.gov (United States)

    Watanuki, Zenta; Kosai, Hitomi; Osanai, Nanae; Ogama, Naoko; Mochizuki, Mai; Tamai, Keiichi; Yamaguchi, Kazunori; Satoh, Kennichi; Fukuhara, Tatsuro; Maemondo, Makoto; Ichinose, Masakazu; Nukiwa, Toshihiro; Tanaka, Nobuyuki

    2014-12-12

    EGFR is an important therapeutic target for non-small cell lung cancers (NSCLCs). Tyrosine kinase inhibitors (TKIs), such as gefitinib and erlotinib, are effective in cases with EGFR-activating mutations. However, most such cases become resistant through a secondary EGFR mutation, T790M. While the second-generation TKI afatinib has a higher affinity for double-mutant EGFRs, better efficacy is needed. Combining afatinib with the anti-EGFR monoclonal antibody cetuximab improves clinical outcomes, but the mechanism is unclear. Here we examined this effect using erythroleukemic K562 cells. The activating EGFR mutation L858R is sensitive to first-generation TKIs, and adding T790M confers resistance to these drugs. This double-mutant EGFR was moderately sensitive to afatinib, but responded weakly to cetuximab. Combined afatinib and cetuximab synergistically increased their cytotoxicity for K562 cells expressing the double-mutant EGFR. Apoptosis in these cells followed induction of the pro-apoptotic protein BIM. Unexpectedly, afatinib caused redistribution of EGFR to the cell surface through Rab11a-dependent recycling. Cetuximab reduced cell-surface EGFR, and total EGFR decreased synergistically when cetuximab was combined with afatinib. Our results suggest that the synergistic effect exerted by afatinib and cetuximab on NSCLCs is associated with BIM induction and alterations in EGFR status.

  7. 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...

  8. Gold nanoparticles-conjugated quercetin induces apoptosis via inhibition of EGFR/PI3K/Akt-mediated pathway in breast cancer cell lines (MCF-7 and MDA-MB-231).

    Science.gov (United States)

    Balakrishnan, Solaimuthu; Mukherjee, Sudip; Das, Sourav; Bhat, Firdous Ahmad; Raja Singh, Paulraj; Patra, Chitta Ranjan; Arunakaran, Jagadeesan

    2017-06-01

    Epidermal growth factor plays a major role in breast cancer cell proliferation, survival, and metastasis. Quercetin, a bioactive flavonoid, is shown to exhibit anticarcinogenic effects against various cancers including breast cancer. Hence, the present study was designed to evaluate the effects of gold nanoparticles-conjugated quercetin (AuNPs-Qu-5) in MCF-7 and MDA-MB-231 breast cancer cell lines. Borohydride reduced AuNPs were synthesized and conjugated with quercetin to yield AuNPs-Qu-5. Both were thoroughly characterized by several physicochemical techniques, and their cytotoxic effects were assessed by MTT assay. Apoptotic studies such as DAPI, AO/EtBr dual staining, and annexin V-FITC staining were performed. AuNPs and AuNPs-Qu-5 were spherical with crystalline nature, and the size of particles range from 3.0 to 4.5 nm. AuNPs-Qu-5 exhibited lower IC50 value compared to free Qu. There was a considerable increase in apoptotic population with increased nuclear condensation seen upon treatment with AuNPs-Qu-5. To delineate the molecular mechanism behind its apoptotic role, we analysed the proteins involved in apoptosis and epidermal growth factor receptor (EGFR)-mediated PI3K/Akt/GSK-3β signalling by immunoblotting and immunocytochemistry. The pro-apoptotic proteins (Bax, Caspase-3) were found to be up regulated and anti-apoptotic protein (Bcl-2) was down regulated on treatment with AuNPs-Qu-5. Additionally, AuNPs-Qu-5 treatment inhibited the EGFR and its downstream signalling molecules PI3K/Akt/mTOR/GSK-3β. In conclusion, administration of AuNPs-Qu-5 in breast cancer cell lines curtails cell proliferation through induction of apoptosis and also suppresses EGFR signalling. AuNPs-Qu-5 is more potent than free quercetin in causing cancer cell death, and hence, this could be a potential drug delivery system in breast cancer therapy. Copyright © 2017 John Wiley & Sons, Ltd.

  9. 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

  10. Next-Generation EGFR Tyrosine Kinase Inhibitors for Treating EGFR-Mutant Lung Cancer beyond First Line.

    Science.gov (United States)

    Sullivan, Ivana; Planchard, David

    2016-01-01

    Tyrosine kinase inhibitors (TKIs) against the human epidermal growth factor receptor (EGFR) are now standard treatment in the clinic for patients with advanced EGFR mutant non-small-cell lung cancer (NSCLC). First-generation EGFR TKIs, binding competitively and reversibly to the ATP-binding site of the EGFR tyrosine kinase domain, have resulted in a significant improvement in outcome for NSCLC patients with activating EGFR mutations (L858R and Del19). However, after a median duration of response of ~12 months, all patients develop tumor resistance, and in over half of these patients this is due to the emergence of the EGFR T790M resistance mutation. The second-generation EGFR/HER TKIs were developed to treat resistant disease, targeting not only T790M but EGFR-activating mutations and wild-type EGFR. Although they exhibited promising anti-T790M activity in the laboratory, their clinical activity among T790M+ NSCLC was poor mainly because of dose-limiting toxicity due to simultaneous inhibition of wild-type EGFR. The third-generation EGFR TKIs selectively and irreversibly target EGFR T790M and activating EGFR mutations, showing promising efficacy in NSCLC resistant to the first- and second-generation EGFR TKIs. They also appear to have lower incidences of toxicity due to the limited inhibitory effect on wild-type EGFR. Currently, the first-generation gefitinib and erlotinib and second-generation afatinib have been approved for first-line treatment of metastatic NSCLC with activating EGFR mutations. Among the third-generation EGFR TKIs, osimertinib is today the only drug approved by the Food and Drug Administration and the European Medicines Agency to treat metastatic EGFR T790M NSCLC patients who have progressed on or after EGFR TKI therapy. In this review, we summarize the available post-progression therapies including third-generation EGFR inhibitors and combination treatment strategies for treating patients with NSCLC harboring EGFR mutations and address the

  11. 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.

  12. 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.

  13. EGFR Mutation Status in Uighur Lung Adenocarcinoma Patients

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    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%.

  14. Pyrosequencing for EGFR mutation detection: diagnostic accuracy and clinical implications.

    Science.gov (United States)

    Sahnane, Nora; Gueli, Rossana; Tibiletti, Maria G; Bernasconi, Barbara; Stefanoli, Michele; Franzi, Francesca; Pinotti, Graziella; Capella, Carlo; Furlan, Daniela

    2013-12-01

    EGFR-activating mutations predict responsiveness to EGFR tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC) patients. Mutation screening is crucial to support therapeutic decisions and is commonly conducted using dideoxy sequencing, although its sensitivity is suboptimal in clinical settings. To evaluate the diagnostic performance of pyrosequencing and dideoxy sequencing, we examined EGFR mutation status in a retrospective cohort of 53 patients with NSCLCs clinically selected for TKI therapy and whose clinical outcome was available. Moreover, pyrosequencing quantitative results were compared with EGFR amplification data. EGFR mutations were investigated by pyrosequencing and by dideoxy sequencing. Detection rates of both methods were determined by titration assays using NCI-H1975 and HCC-827 cell lines. Increased EGFR copy number was assessed by fluorescence in situ hybridization (FISH). Pyrosequencing showed a higher detection rate than dideoxy sequencing. Tumor control rate of cases with mutant and wild-type EGFR was 86% and 29%, respectively. EGFR amplification was significantly associated with EGFR mutation and a positive correlation between high percentages of mutant alleles and clinical response to TKI was observed. We concluded that pyrosequencing is more sensitive than dideoxy sequencing in mutation screening for EGFR mutations. Detection rate of dideoxy sequencing was suboptimal when low frequencies of mutant alleles or low tumor cell contents were observed. Pyrosequencing enables quantification of mutant alleles that correlates well with increased EGFR copy number assessed by FISH. Pyrosequencing should be used in molecular diagnostic of NSCLC to appropriately select patients who are likely to benefit from TKI therapy.

  15. Afatinib, an Irreversible EGFR Family Inhibitor, Shows Activity Toward Pancreatic Cancer Cells, Alone and in Combination with Radiotherapy, Independent of KRAS Status.

    Science.gov (United States)

    Huguet, Florence; Fernet, Marie; Giocanti, Nicole; Favaudon, Vincent; Larsen, Annette K

    2016-06-01

    Pancreatic adenocarcinoma is characterized by a high frequency of KRAS mutations and frequent deregulation of the epidermal growth factor receptor (EGFR) and other EGFR family members such as HER2/ErbB2. The EGFR inhibitor erlotinib is approved for treatment of pancreatic cancer, but has shown modest activity in most patients. Here we investigated the activity of afatinib, a second-generation irreversible pan-EGFR family kinase inhibitor, alone or in combination with ionizing radiation, toward pancreatic cancer cells. The influence of afatinib on cell proliferation, cell cycle distribution, clonogenic survival, nuclear fragmentation, ploidy, and centrosome amplification following irradiation was determined. Expression and phosphorylation of HER receptors, Akt, DNA-PKcs, and ERK1/2 was characterized by Western blot analysis. Afatinib was growth-inhibitory for all three cell lines but cytotoxic only toward BxPC3 (KRAS (wt)) and Capan-2 (KRAS (mut)) cells, both of which express high levels of EGFR, HER2, and HER3 receptors. Afatinib increased the radiosensitivity of BxPC3 and Capan-2 cells, prevented the radio-induced phosphorylation of Akt, and induced mitotic catastrophe following irradiation. In comparison, Panc-1 cells (KRAS (mut)) expressing low levels of EGFR family receptors were resistant to afatinib-induced radiosensitization. These results must be confirmed in vivo. Afatinib showed cytotoxic and radiosensitizing effects toward a subset of pancreatic cancer cells which was closely correlated with expression of EGFR, HER2, and HER3 receptors, but not with KRAS status.

  16. Distinct effects of EGFR ligands on human mammary epithelial cell differentiation.

    Directory of Open Access Journals (Sweden)

    Chandrani Mukhopadhyay

    Full Text Available Based on gene expression patterns, breast cancers can be divided into subtypes that closely resemble various developmental stages of normal mammary epithelial cells (MECs. Thus, understanding molecular mechanisms of MEC development is expected to provide critical insights into initiation and progression of breast cancer. Epidermal growth factor receptor (EGFR and its ligands play essential roles in normal and pathological mammary gland. Signals through EGFR is required for normal mammary gland development. Ligands for EGFR are over-expressed in a significant proportion of breast cancers, and elevated expression of EGFR is associated with poorer clinical outcome. In the present study, we examined the effect of signals through EGFR on MEC differentiation using the human telomerase reverse transcriptase (hTERT-immortalized human stem/progenitor MECs which express cytokeratin 5 but lack cytokeratin 19 (K5(+K19(- hMECs. As reported previously, these cells can be induced to differentiate into luminal and myoepithelial cells under appropriate culture conditions. K5(+K19(- hMECs acquired distinct cell fates in response to EGFR ligands epidermal growth factor (EGF, amphiregulin (AREG and transforming growth factor alpha (TGFα in differentiation-promoting MEGM medium. Specifically, presence of EGF during in vitro differentiation supported development into both luminal and myoepithelial lineages, whereas cells differentiated only towards luminal lineage when EGF was replaced with AREG. In contrast, substitution with TGFα led to differentiation only into myoepithelial lineage. Chemical inhibition of the MEK-Erk pathway, but not the phosphatidylinositol 3-kinase (PI3K-AKT pathway, interfered with K5(+K19(- hMEC differentiation. The present data validate the utility of the K5(+K19(- hMEC cells for modeling key features of human MEC differentiation. This system should be useful in studying molecular/biochemical mechanisms of human MEC differentiation.

  17. Acetate Kinase Isozymes Confer Robustness in Acetate Metabolism

    DEFF Research Database (Denmark)

    Chan, Siu Hung Joshua; Nørregaard, Lasse; Solem, Christian

    2014-01-01

    strains reveal that AckA1 has a higher capacity for acetate production which allows faster growth in an environment with high acetate concentration. Meanwhile, AckA2 is important for fast acetate-dependent growth at low concentration of acetate. The results demonstrate that the two ACKs have complementary...

  18. Afatinib increases sensitivity to radiation in non-small cell lung cancer cells with acquired EGFR T790M mutation.

    Science.gov (United States)

    Zhang, Shirong; Zheng, Xiaoliang; Huang, Haixiu; Wu, Kan; Wang, Bing; Chen, Xufeng; Ma, Shenglin

    2015-03-20

    Afatinib is a second-generation of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor and has shown a significant clinical benefit in non-small cell lung cancer (NSCLC) patients with EGFR-activating mutations. However, the potential therapeutic effects of afatinib combining with other modalities, including ionizing radiation (IR), are not well understood. In this study, we developed a gefitinib-resistant cell subline (PC-9-GR) with a secondary EGFR mutation (T790M) from NSCLC PC-9 cells after chronic exposures to increasing doses of gefitinib. The presence of afatinib significantly increases the cell killing effect of radiation in PC-9-GR cells harboring acquired T790M, but not in H1975 cells with de novo T790M or in H460 cells that express wild-type EGFR. In PC-9-GR cells, afatinib remarkable blocks baseline of EGFR and ERK phosphorylations, and causes delay of IR-induced AKT phosphorylation. Afatinib treatment also leads to increased apoptosis and suppressed DNA damage repair in irradiated PC-9-GR cells, and enhanced tumor growth inhibition when combined with IR in PC-9-GR xenografts. Our findings suggest a potential therapeutic impact of afatinib as a radiation sensitizer in lung cancer cells harboring acquired T790M mutation, providing a rationale for a clinical trial with combination of afatinib and radiation in NSCLCs with EGFR T790M mutation.

  19. 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.

  20. Development of tetravalent IgG1 dual targeting IGF-1R-EGFR antibodies with potent tumor inhibition.

    Science.gov (United States)

    Croasdale, Rebecca; Wartha, Katharina; Schanzer, Juergen M; Kuenkele, Klaus-Peter; Ries, Carola; Mayer, Klaus; Gassner, Christian; Wagner, Martina; Dimoudis, Nikolaos; Herter, Sylvia; Jaeger, Christiane; Ferrara, Claudia; Hoffmann, Eike; Kling, Lothar; Lau, Wilma; Staack, Roland F; Heinrich, Julia; Scheuer, Werner; Stracke, Jan; Gerdes, Christian; Brinkmann, Ulrich; Umana, Pablo; Klein, Christian

    2012-10-15

    In this study we present novel bispecific antibodies that simultaneously target the insulin-like growth factor receptor type I (IGF-1R) and epidermal growth factor receptor (EGFR). For this purpose disulfide stabilized scFv domains of the EGFR/ADCC antibody GA201 were fused via serine-glycine connectors to the C-terminus of the heavy (XGFR2) or light chain (XGFR4), or the N-termini of the light (XGFR5) or heavy chain (XGFR3) of the IGF-1R antibody R1507 as parental IgG1 antibody. The resulting bispecific IGF-1R-EGFR antibodies XGFR2, XGFR3 and XGFR4 were successfully generated with yields and stability comparable to conventional IgG1 antibodies. They effectively inhibited IGF-1R and EGFR phosphorylation and 3D proliferation of H322M and H460M2 tumor cells, induced strong down-modulation of IGF-1R as well as enhanced EGFR down-modulation compared to the parental EGFR antibody GA201 and were ADCC competent. The bispecific XGFR derivatives showed a strong format dependent influence of N- or C-terminal heavy and light chain scFv attachment on ADCC activity and an increase in receptor downregulation over the parental combination in vitro. XGFR2 and XGFR4 were selected for in vivo evaluation and showed potent anti-tumoral efficacy comparable to the combination of monospecific IGF-1R and EGFR antibodies in subcutaneous BxPC3 and H322M xenograft models. In summary, we have managed to overcome issues of stability and productivity of bispecific antibodies, discovered important antibody fusion protein design related differences on ADCC activity and receptor downmodulation and show that IGF-1R-EGFR antibodies represent an attractive therapeutic strategy to simultaneously target two key components de-regulated in multiple cancer types, with the ultimate goal to avoid the formation of resistance to therapy.

  1. 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.

  2. 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.

  3. IC-4, a new irreversible EGFR inhibitor, exhibits prominent anti-tumor and anti-angiogenesis activities.

    Science.gov (United States)

    Li, Ying-Bo; Wang, Zhong-Qing; Yan, Xu; Chen, Mei-Wan; Bao, Jiao-Lin; Wu, Guo-Sheng; Ge, Ze-Mei; Zhou, De-Min; Wang, Yi-Tao; Li, Run-Tao

    2013-10-28

    Accumulating evidence suggested that the irreversible tyrosine kinase inhibitors (TKIs) have potential to override the acquired resistance to target-based therapies. Herein, we reported IC-4 as a novel irreversible TKI for epidermal growth factor receptor (EGFR). IC-4 potentially suppressed proliferation, induced apoptosis and a G2/M cell cycle arrest in breast cancer cells, correlating with inhibition of EGF-induced EGFR activation, but independent of DNA damage. In addition, IC-4 exhibited anti-angiogenetic activities both in vitro and in vivo. It suppressed cell viability and proliferation induced by various growth factors in human umbilical vein endothelial cells (HUVECs). IC-4 also inhibited HUVECs migration and tube formation. In transgenic zebrafish embryo model, IC-4 was shown to suppress formation of intersegmental vessel and development of subintestinal vessels. Taken together, these results demonstrated that IC-4 is a new irreversible EGFR-TKI, exhibiting potent anti-breast cancer and anti-angiogenetic effects.

  4. 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.

  5. Loss of activating EGFR mutant gene contributes to acquired resistance to EGFR tyrosine kinase inhibitors in lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Keisuke Tabara

    Full Text Available Non-small-cell lung cancer harboring epidermal growth factor receptor (EGFR mutations attains a meaningful response to EGFR-tyrosine kinase inhibitors (TKIs. However, acquired resistance to EGFR-TKIs could affect long-term outcome in almost all patients. To identify the potential mechanisms of resistance, we established cell lines resistant to EGFR-TKIs from the human lung cancer cell lines PC9 and11-18, which harbored activating EGFR mutations. One erlotinib-resistant cell line from PC9 and two erlotinib-resistant cell lines and two gefitinib-resistant cell lines from 11-18 were independently established. Almost complete loss of mutant delE746-A750 EGFR gene was observed in the erlotinib-resistant cells isolated from PC9, and partial loss of the mutant L858R EGFR gene copy was specifically observed in the erlotinib- and gefitinib-resistant cells from 11-18. However, constitutive activation of EGFR downstream signaling, PI3K/Akt, was observed even after loss of the mutated EGFR gene in all resistant cell lines even in the presence of the drug. In the erlotinib-resistant cells from PC9, constitutive PI3K/Akt activation was effectively inhibited by lapatinib (a dual TKI of EGFR and HER2 or BIBW2992 (pan-TKI of EGFR family proteins. Furthermore, erlotinib with either HER2 or HER3 knockdown by their cognate siRNAs also inhibited PI3K/Akt activation. Transfection of activating mutant EGFR complementary DNA restored drug sensitivity in the erlotinib-resistant cell line. Our study indicates that loss of addiction to mutant EGFR resulted in gain of addiction to both HER2/HER3 and PI3K/Akt signaling to acquire EGFR-TKI resistance.

  6. 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.

  7. Sulindac metabolites induce proteosomal and lysosomal degradation of the epidermal growth factor receptor.

    Science.gov (United States)

    Pangburn, Heather A; Ahnen, Dennis J; Rice, Pamela L

    2010-04-01

    The epidermal growth factor receptor (EGFR) is a member of the ErbB family of receptor tyrosine kinases. In response to ligand, EGFR is internalized and degraded by the ubiquitin-proteasome/lysosome pathway. We previously reported that metabolites of the nonsteroidal anti-inflammatory drug sulindac downregulate the expression of EGFR and inhibit basal and EGF-induced EGFR signaling through extracellular signal-regulated kinase 1/2. We now have evaluated the mechanisms of sulindac metabolite-induced downregulation of EGFR. EGF-induced downregulation of EGFR occurs within 10 minutes and lasts for 24 hours. By contrast, downregulation of EGFR by sulindac sulfide and sulindac sulfone was first evident at 4 and 24 hours, respectively, with maximal downregulation at 72 hours. Pretreatment with either the lysosomal inhibitor chloroquine or the proteosomal inhibitor MG132 blocked sulindac metabolite-induced downregulation of EGFR. Sulindac metabolites also increased the ubiquitination of EGFR. Whereas sulindac metabolites inhibited phosphorylation of EGFR pY1068, they increased phosphorylation of EGFR pY1045, the docking site where c-Cbl binds, thereby enabling receptor ubiquitination and degradation. Immunofluorescence analysis of EGF and EGFR distribution confirmed the biochemical observations that sulindac metabolites alter EGFR localization and EGFR internalization in a manner similar to that seen with EGF treatment. Expression of ErbB family members HER2 and HER3 was also downregulated by sulindac metabolites. We conclude that downregulation of EGFR expression by sulindac metabolites is mediated via lysosomal and proteosomal degradation that may be due to drug-induced phosphorylation at pY1045 with resultant ubiquitination of EGFR. Thus, sulindac metabolite-induced downregulation of EGFR seems to be mediated through mechanism(s) similar, at least in part, to those involved in EGF-induced downregulation of EGFR.

  8. 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

  9. Inhibition of IGF1R signaling abrogates resistance to afatinib (BIBW2992) in EGFR T790M mutant lung cancer cells.

    Science.gov (United States)

    Lee, Yongik; Wang, Yian; James, Michael; Jeong, Joseph H; You, Ming

    2016-05-01

    Non-small cell lung cancer (NSCLC) patients with an epidermal growth factor receptor (EGFR) mutation have benefited from treatment of reversible EGFR tyrosine kinase inhibitors (TKIs) such as gefitinib and erlotinib. Acquisition of a secondary mutation in EGFR T790M is the most common mechanism of resistance to first generation EGFR TKIs, resulting in therapeutic failure. Afatinib is a second generation of EGFR TKI that showed great efficacy against tumors bearing the EGFR T790M mutation, but it failed to show the improvement on overall survival of lung cancer patients with EGFR mutations possibly because of novel acquired resistance mechanisms. Currently, there are no therapeutic options available for lung cancer patients who develop acquired resistance to afatinib. To identify novel resistance mechanism(s) to afatinib, we developed afatinib resistant cell lines from a parental human-derived NSCLC cell line, H1975, harboring both EGFR L858R and T790M mutations. We found that activation of the insulin-like growth factor 1 receptor (IGF1R) signaling pathway contributes to afatinib resistance in NSCLC cells harboring the T790M mutation. IGF1R knockdown not only significantly sensitizes resistant cells to afatinib, but also induces apoptosis in afatinib resistance cells. In addition, combination treatment with afatinib and linsitinib shows more than additive effects on tumor growth in in vivo H1975 xenograft. Therefore, these finding suggest that IGF1R inhibition or combination of EGFR-IGF1R inhibition strategies would be potential ways to prevent or potentiate the effects of current therapeutic options to lung cancer patients demonstrating resistance to either first or second generation EGFR TKIs.

  10. Constitutively activated ERK sensitizes cancer cells to doxorubicin: Involvement of p53-EGFR-ERK pathway

    Indian Academy of Sciences (India)

    RATNA KUMARI; SURBHI CHOUHAN; SNAHLATA SINGH; RISHI RAJ CHHIPA; AMRENDRA KUMAR AJAY; MANOJ KUMAR BHAT

    2017-03-01

    The tumour suppressor gene p53 is mutated in approximately 50% of the human cancers. p53 is involved in genotoxicstress-induced cellular responses. The role of EGFR and ERK in DNA-damage-induced apoptosis is well known. Weinvestigated the involvement of activation of ERK signalling as a consequence of non-functional p53, in sensitivity ofcells to doxorubicin. We performed cell survival assays in cancer cell lines with varying p53 status: MCF-7 (wild-typep53, WTp53), MDA MB-468 (mutant p53, MUTp53), H1299 (absence of p53, NULLp53) and an isogenic cell lineMCF-7As (WTp53 abrogated). Our results indicate that enhanced chemosensitivity of cells lacking wild-type p53function is because of elevated levels of EGFR which activates ERK. Additionally, we noted that independent of p53status, pERK contributes to doxorubicin-induced cell death.

  11. 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

  12. Integrin α5β1 simultaneously controls EGFR-dependent proliferation and Akt-dependent pro-survival signaling in epidermoid carcinoma cells

    OpenAIRE

    2012-01-01

    To delineate distinctive role of the components of α5β1 integrin-EGFR axis in control of epidermoid carcinoma cell proliferation, we performed individual inhibition of α5β1 and EGFR via genetic and phamacological methods, respectively. We demonstrated that pharmacological inhibition of epidermal growth factor receptor (EGFR) significantly affected proliferation of A431 human cells by inducing the G0/G1 cell cycle arrest, whereas shRNA-mediated depletion of α5 subunit of α5β1 integrin led to a...

  13. 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. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  14. Review of EGFR TKIs in metastatic NSCLC, including ongoing trials

    Directory of Open Access Journals (Sweden)

    Barbara eMelosky

    2014-09-01

    Full Text Available Recent clinical trials have demonstrated the efficacy of epidermal growth factor receptor (EGFR tyrosine kinase inhibitors (TKI in the treatment of patients with advanced metastatic non-small cell lung cancer. Most of these recent trials were conducted in patients with EGFR mutation-positive tumours. As our knowledge of the EGFR mutation and its resistant pathways develops, the complexity of the situation expands. This article briefly reviews the pivotal trials leading to approval of EGFR TKIs in the first-line setting for patients with EGFR mutation-positive non-small cell lung carcinomas. It discusses the historical use of EGFR TKIs after the first line setting in unselected patients and briefly describes ongoing trials.

  15. 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.

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

    Science.gov (United States)

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

    2013-09-06

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

  17. EFFECT OF LEAD ACETATE

    African Journals Online (AJOL)

    MICROSOFT

    suspicion of poisoning are illnesses in a number of pre- viously healthy animals, at the same time, and showing. *Corresponding ... hepatocytes, the major cell type in the liver. ALT is often ... level is also increased in cases of liver cell death resulting from ...... Acetate on the Neural Development of Chick Embryos. Radostitis ...

  18. EGFR Signal-Network Reconstruction Demonstrates Metabolic Crosstalk in EMT.

    Directory of Open Access Journals (Sweden)

    Kumari Sonal Choudhary

    2016-06-01

    Full Text Available Epithelial to mesenchymal transition (EMT is an important event during development and cancer metastasis. There is limited understanding of the metabolic alterations that give rise to and take place during EMT. Dysregulation of signalling pathways that impact metabolism, including epidermal growth factor receptor (EGFR, are however a hallmark of EMT and metastasis. In this study, we report the investigation into EGFR signalling and metabolic crosstalk of EMT through constraint-based modelling and analysis of the breast epithelial EMT cell model D492 and its mesenchymal counterpart D492M. We built an EGFR signalling network for EMT based on stoichiometric coefficients and constrained the network with gene expression data to build epithelial (EGFR_E and mesenchymal (EGFR_M networks. Metabolic alterations arising from differential expression of EGFR genes was derived from a literature review of AKT regulated metabolic genes. Signaling flux differences between EGFR_E and EGFR_M models subsequently allowed metabolism in D492 and D492M cells to be assessed. Higher flux within AKT pathway in the D492 cells compared to D492M suggested higher glycolytic activity in D492 that we confirmed experimentally through measurements of glucose uptake and lactate secretion rates. The signaling genes from the AKT, RAS/MAPK and CaM pathways were predicted to revert D492M to D492 phenotype. Follow-up analysis of EGFR signaling metabolic crosstalk in three additional breast epithelial cell lines highlighted variability in in vitro cell models of EMT. This study shows that the metabolic phenotype may be predicted by in silico analyses of gene expression data of EGFR signaling genes, but this phenomenon is cell-specific and does not follow a simple trend.

  19. Role of IKK-alpha in EGFR Signaling Regulation

    Science.gov (United States)

    2013-09-01

    We herein identified a novel posttranslational modification of EGFR which plays an indispensable role in regulation of EGFR signaling pathways. We...stringently modulated by a previously unknown and reversible modification , ubiquitination through a distinct TRAF6 binding motif of GSK3β. The...factor, plays an important role in many cancer types. The modification patterns of EGFR are critical for its function and the understanding of these

  20. Effect of 12-O-tetradecanoylphorbol-13-acetate-induced psoriasis-like skin lesions on systemic inflammation and atherosclerosis in hypercholesterolaemic apolipoprotein E deficient mice

    DEFF Research Database (Denmark)

    Madsen, Marie; Hansen, Peter Riis; Nielsen, Lars Bo

    2016-01-01

    to develop an animal model with combined atherosclerosis and psoriasis-like skin inflammation. METHODS: Topical 12-O-tetradecanoylphorbol-13-acetate (TPA) was applied to the ears twice per week for 8 weeks in atherosclerosis-prone apolipoprotein E deficient (ApoE(-/-)) mice. RESULTS: TPA led to localized...... skin inflammation with increased epidermal thickness, infiltration of inflammatory-like cells and augmented tissue interleukin-17F levels. Systemic effects of the topical application of TPA were demonstrated by increased plasma concentration of serum amyloid A and splenic immune modulation...