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Sample records for activated egfr determines

  1. EGFR Activation by Spatially Restricted Ligands

    National Research Council Canada - National Science Library

    Clouse, Katherine N; Goodrich, Jennifer S

    2006-01-01

    ...) activity has been associated with an increased prognosis of breast cancer. During cogenesis in Drosophila melanogaster local Egfr activation by the spatially-restricted TGFalpha-like ligand Gurken (Grk...

  2. EGFR Activation by Spatially Restricted Ligands

    National Research Council Canada - National Science Library

    Goodrich, Jennifer S

    2005-01-01

    ...) activity has been associated with an increased prognosis of breast cancer. During oogenesis in Drosophila melanogaster, local EGFR activation by the spatially restricted TGF alpha-like ligand, Gurken (Grk...

  3. EGFR Activation by Spatially Restricted Ligands

    National Research Council Canada - National Science Library

    Clouse, Katherine N; Goodrich, Jennifer S

    2006-01-01

    ...) functions in the localization and translational regulation of grk mRNA. The purpose of this project is to identify factors that function with Sqd to produce spatially-restricted Egfr activation...

  4. EGFR Activation by Spatially Restricted Ligands

    National Research Council Canada - National Science Library

    Goodrich, Jennifer S

    2005-01-01

    ...) functions in the localization and translational regulation of grk mRNA. The purpose of this project is to identify factors that function with Squid to produce spatially-restricted EGFR activation...

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

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    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.

  6. Frequent activation of EGFR in advanced chordomas

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    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

  7. EGFR Activation and Ultraviolet Light‐Induced Skin Carcinogenesis

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    Taghrid B. El-Abaseri

    2007-01-01

    Full Text Available The epidermal growth factor receptor (EGFR regulates the proliferation of keratinocytes through multiple mechanisms that differ depending on the localization of the cell within the skin. Ultraviolet (UV irradiation, the main etiologic factor in the development of skin cancer, also activates the receptor. In this review, we discuss how the UV-induced activation of EGFR regulates the response of the skin to UV. UV-induced EGFR activation increases keratinocyte proliferation, suppresses apoptosis, and augments and accelerates epidermal hyperplasia in response to UV. Pharmacological inhibition of the UV-induced activation of EGFR in a genetically initiated mouse skin tumorigenesis model suppresses tumorigenesis and the activation of mitogen-activated protein (MAP kinases and phosphatidyl inositol-3-kinase (PI3K/AKT signaling pathways. EGFR has pleiotropic, complex, and cell-type-specific functions in cutaneous keratinocytes; suggesting that the receptor is an appropriate target for the development of molecularly targeted therapies for skin cancer and other pathologies.

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

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    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.

  9. Determination of EGFR and KRAS mutational status in Greek non-small-cell lung cancer patients.

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    Papadopoulou, Eirini; Tsoulos, Nikolaos; Tsirigoti, Angeliki; Apessos, Angela; Agiannitopoulos, Konstantinos; Metaxa-Mariatou, Vasiliki; Zarogoulidis, Konstantinos; Zarogoulidis, Pavlos; Kasarakis, Dimitrios; Kakolyris, Stylianos; Dahabreh, Jubrail; Vlastos, Fotis; Zoublios, Charalampos; Rapti, Aggeliki; Papageorgiou, Niki Georgatou; Veldekis, Dimitrios; Gaga, Mina; Aravantinos, Gerasimos; Karavasilis, Vasileios; Karagiannidis, Napoleon; Nasioulas, George

    2015-10-01

    It has been reported that certain patients with non-small-cell lung cancer (NSCLC) that harbor activating somatic mutations within the tyrosine kinase domain of the epidermal growth factor receptor ( EGFR ) gene may be effectively treated using targeted therapy. The use of EGFR inhibitors in patient therapy has been demonstrated to improve response and survival rates; therefore, it was suggested that clinical screening for EGFR mutations should be performed for all patients. Numerous clinicopathological factors have been associated with EGFR and Kirsten-rat sarcoma oncogene homolog (KRAS) mutational status including gender, smoking history and histology. In addition, it was reported that EGFR mutation frequency in NSCLC patients was ethnicity-dependent, with an incidence rate of ~30% in Asian populations and ~15% in Caucasian populations. However, limited data has been reported on intra-ethnic differences throughout Europe. The present study aimed to investigate the frequency and spectrum of EGFR mutations in 1,472 Greek NSCLC patients. In addition, KRAS mutation analysis was performed in patients with known smoking history in order to determine the correlation of type and mutation frequency with smoking. High-resolution melting curve (HRM) analysis followed by Sanger sequencing was used to identify mutations in exons 18-21 of the EGFR gene and in exon 2 of the KRAS gene. A sensitive next-generation sequencing (NGS) technology was also employed to classify samples with equivocal results. The use of sensitive mutation detection techniques in a large study population of Greek NSCLC patients in routine diagnostic practice revealed an overall EGFR mutation frequency of 15.83%. This mutation frequency was comparable to that previously reported in other European populations. Of note, there was a 99.8% concordance between the HRM method and Sanger sequencing. NGS was found to be the most sensitive method. In addition, female non-smokers demonstrated a high prevalence of

  10. Tumor heterogeneity is an active process maintained by a mutant EGFR-induced cytokine circuit in glioblastoma.

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    Inda, Maria-del-Mar; Bonavia, Rudy; Mukasa, Akitake; Narita, Yoshitaka; Sah, Dinah W Y; Vandenberg, Scott; Brennan, Cameron; Johns, Terrance G; Bachoo, Robert; Hadwiger, Philipp; Tan, Pamela; Depinho, Ronald A; Cavenee, Webster; Furnari, Frank

    2010-08-15

    Human solid tumors frequently have pronounced heterogeneity of both neoplastic and normal cells on the histological, genetic, and gene expression levels. While current efforts are focused on understanding heterotypic interactions between tumor cells and surrounding normal cells, much less is known about the interactions between and among heterogeneous tumor cells within a neoplasm. In glioblastoma multiforme (GBM), epidermal growth factor receptor gene (EGFR) amplification and mutation (EGFRvIII/DeltaEGFR) are signature pathogenetic events that are invariably expressed in a heterogeneous manner. Strikingly, despite its greater biological activity than wild-type EGFR (wtEGFR), individual GBM tumors expressing both amplified receptors typically express wtEGFR in far greater abundance than the DeltaEGFR lesion. We hypothesized that the minor DeltaEGFR-expressing subpopulation enhances tumorigenicity of the entire tumor cell population, and thereby maintains heterogeneity of expression of the two receptor forms in different cells. Using mixtures of glioma cells as well as immortalized murine astrocytes, we demonstrate that a paracrine mechanism driven by DeltaEGFR is the primary means for recruiting wtEGFR-expressing cells into accelerated proliferation in vivo. We determined that human glioma tissues, glioma cell lines, glioma stem cells, and immortalized mouse Ink4a/Arf(-/-) astrocytes that express DeltaEGFR each also express IL-6 and/or leukemia inhibitory factor (LIF) cytokines. These cytokines activate gp130, which in turn activates wtEGFR in neighboring cells, leading to enhanced rates of tumor growth. Ablating IL-6, LIF, or gp130 uncouples this cellular cross-talk, and potently attenuates tumor growth enhancement. These findings support the view that a minor tumor cell population can potently drive accelerated growth of the entire tumor mass, and thereby actively maintain tumor cell heterogeneity within a tumor mass. Such interactions between genetically

  11. Convergent Akt activation drives acquired EGFR inhibitor resistance in lung cancer

    DEFF Research Database (Denmark)

    Jacobsen, Kirstine; Bertran-Alamillo, Jordi; Molina, Miguel Angel

    2017-01-01

    Non-small-cell lung cancer patients with activating epidermal growth factor receptor (EGFR) mutations typically benefit from EGFR tyrosine kinase inhibitor treatment. However, virtually all patients succumb to acquired EGFR tyrosine kinase inhibitor resistance that occurs via diverse mechanisms....... The diversity and unpredictability of EGFR tyrosine kinase inhibitor resistance mechanisms presents a challenge for developing new treatments to overcome EGFR tyrosine kinase inhibitor resistance. Here, we show that Akt activation is a convergent feature of acquired EGFR tyrosine kinase inhibitor resistance......, across a spectrum of diverse, established upstream resistance mechanisms. Combined treatment with an EGFR tyrosine kinase inhibitor and Akt inhibitor causes apoptosis and synergistic growth inhibition in multiple EGFR tyrosine kinase inhibitor-resistant non-small-cell lung cancer models. Moreover...

  12. HPV infection and EGFR activation/alteration in HIV-infected East African patients with conjunctival carcinoma.

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    Jing Jie Yu

    2010-05-01

    Full Text Available There has been substantial growth in the numbers of patients with conjunctival squamous cell carcinoma infected with HIV in East Africa. The natural history of the conjunctival squamous cell carcinoma appears to be unique in this region of the world, but the etiologic mechanism unclear and therapeutic options limited. This research was carried out to determine if conjunctival squamous cell carcinoma harbors human papillomavirus DNA and is associated with activation of the EGFR signaling pathway. Positive findings would identify etiologic causes and provide clinical guidance to improve treatment.Expression of p-MAPK/MAPK, p-Akt/Akt and p-EGFR/EGFR in cell nuclei and cytoplasm of 38 FFPE specimens were assessed by immunohistochemistry; HPV genotype was detected by qPCR assay; EGFR mutation was assessed by DNA sequencing analysis; and EGFR mRNA expression was measured using relative qPCR. Statistical analyses included two-sided Fisher exact test or chi-square test, Spearman correlation coefficient and ANOVA. HPV 18 was found in 61% of samples, with HPV 16 double-genotype in 6 patients (16%. Immunohistochemistry and qPCR data suggest that activation and expression of the EGFR signaling pathway is related to disease progression of conjunctival cancer. The associations between cytoplasmic p-MAPK, cytoplasmic p-Akt and tumor invasiveness were significant (p = 0.05 or 0.028. Nuclear p-EGFR appeared only in invasive tumors. A significant positive association between EGFR expression and disease invasiveness was observed (p = 0.01. A SNP in 10 patients and one missense mutation were found within EGFR tyrosine kinase domain. Statistical analysis indicates that patients with measurable EGFR expression more likely harbor EGFR mutations, compared to those with negative EGFR expression (35.3% vs. 0%.We conclude that HPV types 16/18 infection is frequent in East African patients with AIDS-associated squamous cell carcinoma of the conjunctiva. EGFR activation

  13. Convergent Akt activation drives acquired EGFR inhibitor resistance in lung cancer

    DEFF Research Database (Denmark)

    Jacobsen, Kirstine; Bertran-Alamillo, Jordi; Molina, Miguel Angel

    2017-01-01

    Non-small-cell lung cancer patients with activating epidermal growth factor receptor (EGFR) mutations typically benefit from EGFR tyrosine kinase inhibitor treatment. However, virtually all patients succumb to acquired EGFR tyrosine kinase inhibitor resistance that occurs via diverse mechanisms....

  14. Collagen type I induces EGFR-TKI resistance in EGFR-mutated cancer cells by mTOR activation through Akt-independent pathway.

    Science.gov (United States)

    Yamazaki, Shota; Higuchi, Youichi; Ishibashi, Masayuki; Hashimoto, Hiroko; Yasunaga, Masahiro; Matsumura, Yasuhiro; Tsuchihara, Katsuya; Tsuboi, Masahiro; Goto, Koichi; Ochiai, Atsushi; Ishii, Genichiro

    2018-06-01

    Primary resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) is a serious problem in lung adenocarcinoma patients harboring EGFR mutations. The aim of this study was to examine whether and how collagen type I (Col I), the most abundantly deposited matrix in tumor stroma, affects EGFR-TKI sensitivity in EGFR-mutant cells. We evaluated the EGFR-TKI sensitivity of EGFR-mutated cancer cells cultured with Col I. Changes in the activation of downstream signaling molecules of EGFR were analyzed. We also examined the association between the Col I expression in tumor stroma in surgical specimens and EGFR-TKI response of postoperative recurrence patients with EGFR mutations. Compared to cancer cells without Col I, the survival rate of cancer cells cultured with Col I was significantly higher after EGFR-TKI treatment. In cancer cells cultured with and without Col I, EGFR-TKI suppressed the levels of phosphorylated (p-)EGFR, p-ERK1/2, and p-Akt. When compared to cancer cells without Col I, expression of p-P70S6K, a hallmark of mTOR activation, was dramatically upregulated in cancer cells with Col I. This activation was maintained even after EGFR-TKI treatment. Simultaneous treatment with EGFR-TKI and mTOR inhibitor abrogated Col I-induced resistance to EGFR-TKI. Patients with Col I-rich stroma had a significantly shorter progression-free survival time after EGFR-TKI therapy (238 days vs 404 days; P Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  15. Inhibition of radiation-induced EGFR nuclear import by C225 (Cetuximab) suppresses DNA-PK activity

    International Nuclear Information System (INIS)

    Dittmann, Klaus; Mayer, Claus; Rodemann, Hans-Peter

    2005-01-01

    Background and purpose: Inhibition of EGFR-function can induce radiosensitization in tumor cells. Purpose of our investigation was to identify the possible molecular mechanism of radiosensitization following treatment with anti-EGFR-antibody C225 (Cetuximab). Materials and methods: The effect of C225 on radiation response was determined in human cell lines of bronchial carcinoma (A549) and breast adenoma cells (MDA MB 231). The molecular effects of C225 on EGFR-function after irradiation were analyzed applying western blotting, immune-precipitation and kinase assays. Effects on DNA-repair were detected by quantification of γ-H2AX positive foci 24 h after irradiation. Results: The EGFR specific antibody C225 induced radiosensitization in A549 and also in MDA MB 231 cells. Radiosensitization in A549 was associated with blockage of radiation-induced EGFR transport into the nucleus, and immobilized the complex of EGFR with DNA-dependent protein kinase (DNA-PK) in the cytoplasm. As a consequence radiation-induced DNA-PK activation was abolished, a process that is essential for DNA-repair after radiation exposure. Likewise C225 treatment increased the residual amount of γ-H2AX-positive foci 24 h after irradiation in A549 and in MDA MB 231 cells. Conclusions: Our results suggest that irradiation induced DNA-PK activation-essential for DNA repair-may be hampered specifically by use of the anti-EGFR-antibody C225. This process is associated with radiosensitization

  16. Integrated Experimental and Model-based Analysis Reveals the Spatial Aspects of EGFR Activation Dynamics

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    Shankaran, Harish; Zhang, Yi; Chrisler, William B.; Ewald, Jonathan A.; Wiley, H. S.; Resat, Haluk

    2012-10-02

    The epidermal growth factor receptor (EGFR) belongs to the ErbB family of receptor tyrosine kinases, and controls a diverse set of cellular responses relevant to development and tumorigenesis. ErbB activation is a complex process involving receptor-ligand binding, receptor dimerization, phosphorylation, and trafficking (internalization, recycling and degradation), which together dictate the spatio-temporal distribution of active receptors within the cell. The ability to predict this distribution, and elucidation of the factors regulating it, would help to establish a mechanistic link between ErbB expression levels and the cellular response. Towards this end, we constructed mathematical models for deconvolving the contributions of receptor dimerization and phosphorylation to EGFR activation, and to examine the dependence of these processes on sub-cellular location. We collected experimental datasets for EGFR activation dynamics in human mammary epithelial cells, with the specific goal of model parameterization, and used the data to estimate parameters for several alternate models. Model-based analysis indicated that: 1) signal termination via receptor dephosphorylation in late endosomes, prior to degradation, is an important component of the response, 2) less than 40% of the receptors in the cell are phosphorylated at any given time, even at saturating ligand doses, and 3) receptor dephosphorylation rates at the cell surface and early endosomes are comparable. We validated the last finding by measuring EGFR dephosphorylation rates at various times following ligand addition both in whole cells, and in endosomes using ELISAs and fluorescent imaging. Overall, our results provide important information on how EGFR phosphorylation levels are regulated within cells. Further, the mathematical model described here can be extended to determine receptor dimer abundances in cells co-expressing various levels of ErbB receptors. This study demonstrates that an iterative cycle of

  17. Tyrosine dephosphorylation enhances the therapeutic target activity of epidermal growth factor receptor (EGFR) by disrupting its interaction with estrogen receptor (ER).

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    Ma, Shao; Yin, Ning; Qi, Xiaomei; Pfister, Sandra L; Zhang, Mei-Jie; Ma, Rong; Chen, Guan

    2015-05-30

    Protein-protein interactions can increase or decrease its therapeutic target activity and the determining factors involved, however, are largely unknown. Here, we report that tyrosine-dephosphorylation of epidermal growth factor receptor (EGFR) increases its therapeutic target activity by disrupting its interaction with estrogen receptor (ER). Protein tyrosine phosphatase H1 (PTPH1) dephosphorylates the tyrosine kinase EGFR, disrupts its interaction with the nuclear receptor ER, and increases breast cancer sensitivity to small molecule tyrosine kinase inhibitors (TKIs). These effects require PTPH1 catalytic activity and its interaction with EGFR, suggesting that the phosphatase may increase the sensitivity by dephosphorylating EGFR leading to its dissociation with ER. Consistent with this notion, a nuclear-localization defective ER has a higher EGFR-binding activity and confers the resistance to TKI-induced growth inhibition. Additional analysis show that PTPH1 stabilizes EGFR, stimulates the membranous EGFR accumulation, and enhances the growth-inhibitory activity of a combination therapy of TKIs with an anti-estrogen. Since EGFR and ER both are substrates for PTPH1 in vitro and in intact cells, these results indicate that an inhibitory EGFR-ER protein complex can be switched off through a competitive enzyme-substrate binding. Our results would have important implications for the treatment of breast cancer with targeted therapeutics.

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

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    Ashish Misra

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

  19. Activation of EGFR and ERBB2 by Helicobacter pylori Results in Survival of Gastric Epithelial Cells with DNA Damage

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    Chaturvedi, Rupesh; Asim, Mohammad; Piazuelo, M. Blanca; Yan, Fang; Barry, Daniel P.; Sierra, Johanna Carolina; Delgado, Alberto G.; Hill, Salisha; Casero, Robert A.; Bravo, Luis E.; Dominguez, Ricardo L.; Correa, Pelayo; Polk, D. Brent; Washington, M. Kay; Rose, Kristie L.; Schey, Kevin L.; Morgan, Douglas R.; Peek, Richard M.; Wilson, Keith T.

    2014-01-01

    BACKGROUND & AIMS The gastric cancer-causing pathogen Helicobacter pylori upregulates spermine oxidase (SMOX) in gastric epithelial cells, causing oxidative stress-induced apoptosis and DNA damage. A subpopulation of SMOXhigh cells are resistant to apoptosis, despite their high levels of DNA damage. Because epidermal growth factor receptor (EGFR) activation can regulate apoptosis, we determined its role in SMOX-mediated effects. METHODS SMOX, apoptosis, and DNA damage were measured in gastric epithelial cells from H pylori-infected Egfrwa5 mice (which have attenuated EGFR activity), Egfr wild-type mice, or in infected cells incubated with EGFR inhibitors or deficient in EGFR. Phosphoproteomic analysis was performed. Two independent tissue microarrays containing each stage of disease, from gastritis to carcinoma, and gastric biopsies from Colombian and Honduran cohorts were analyzed by immunohistochemistry. RESULTS SMOX expression and DNA damage were decreased, and apoptosis increased in H pylori-infected Egfrwa5 mice. H pylori-infected cells with deletion or inhibition of EGFR had reduced levels of SMOX, DNA damage, and DNA damagehigh apoptosislow cells. Phosphoproteomic analysis revealed increased EGFR and ERBB2 signaling. Immunoblot analysis demonstrated the presence of a phosphorylated (p)EGFR–ERBB2 heterodimer and pERBB2; knockdown of ErbB2 facilitated apoptosis of DNA damagehigh apoptosislow cells. SMOX was increased in all stages of gastric disease, peaking in tissues with intestinal metaplasia, whereas pEGFR, pEGFR–ERBB2, and pERBB2 were increased predominantly in tissues demonstrating gastritis or atrophic gastritis. Principal component analysis separated gastritis tissues from patients with cancer vs those without cancer. pEGFR, pEGFR–ERBB2, pERBB2, and SMOX were increased in gastric samples from patients whose disease progressed to intestinal metaplasia or dysplasia, compared with patients whose disease did not progress. CONCLUSIONS In an analysis

  20. TGF{beta} induces proHB-EGF shedding and EGFR transactivation through ADAM activation in gastric cancer cells

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    Ebi, Masahide [Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Sciences, Nagoya (Japan); Kataoka, Hiromi, E-mail: hkataoka@med.nagoya-cu.ac.jp [Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Sciences, Nagoya (Japan); Shimura, Takaya; Kubota, Eiji; Hirata, Yoshikazu; Mizushima, Takashi; Mizoshita, Tsutomu; Tanaka, Mamoru; Mabuchi, Motoshi; Tsukamoto, Hironobu; Tanida, Satoshi; Kamiya, Takeshi [Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Sciences, Nagoya (Japan); Higashiyama, Shigeki [Department of Biochemistry and Molecular Genetics, Ehime University Graduate School of Medicine, Ehime (Japan); Joh, Takashi [Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Sciences, Nagoya (Japan)

    2010-11-19

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

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

    International Nuclear Information System (INIS)

    Ebi, Masahide; Kataoka, Hiromi; Shimura, Takaya; Kubota, Eiji; Hirata, Yoshikazu; Mizushima, Takashi; Mizoshita, Tsutomu; Tanaka, Mamoru; Mabuchi, Motoshi; Tsukamoto, Hironobu; Tanida, Satoshi; Kamiya, Takeshi; Higashiyama, Shigeki; Joh, Takashi

    2010-01-01

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

  2. EGFR Activation Mediates Inhibition of Axon Regeneration by Myelin and Chondroitin Sulfate Proteoglycans

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    Koprivica, Vuk; Cho, Kin-Sang; Park, Jong Bae; Yiu, Glenn; Atwal, Jasvinder; Gore, Bryan; Kim, Jieun A.; Lin, Estelle; Tessier-Lavigne, Marc; Chen, Dong Feng; He, Zhigang

    2005-10-01

    Inhibitory molecules associated with myelin and the glial scar limit axon regeneration in the adult central nervous system (CNS), but the underlying signaling mechanisms of regeneration inhibition are not fully understood. Here, we show that suppressing the kinase function of the epidermal growth factor receptor (EGFR) blocks the activities of both myelin inhibitors and chondroitin sulfate proteoglycans in inhibiting neurite outgrowth. In addition, regeneration inhibitors trigger the phosphorylation of EGFR in a calcium-dependent manner. Local administration of EGFR inhibitors promotes significant regeneration of injured optic nerve fibers, pointing to a promising therapeutic avenue for enhancing axon regeneration after CNS injury.

  3. Identifying activating mutations in the EGFR gene: prognostic and therapeutic implications in non-small cell lung cancer.

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    Lopes, Gabriel Lima; Vattimo, Edoardo Filippo de Queiroz; Castro Junior, Gilberto de

    2015-01-01

    Lung cancer is the leading cause of cancer-related deaths worldwide. Promising new therapies have recently emerged from the development of molecular targeted drugs; particularly promising are those blocking the signal transduction machinery of cancer cells. One of the most widely studied cell signaling pathways is that of EGFR, which leads to uncontrolled cell proliferation, increased cell angiogenesis, and greater cell invasiveness. Activating mutations in the EGFR gene (deletions in exon 19 and mutation L858R in exon 21), first described in 2004, have been detected in approximately 10% of all non-squamous non-small cell lung cancer (NSCLC) patients in Western countries and are the most important predictors of a response to EGFR tyrosine-kinase inhibitors (EGFR-TKIs). Studies of the EGFR-TKIs gefitinib, erlotinib, and afatinib, in comparison with platinum-based regimens, as first-line treatments in chemotherapy-naïve patients have shown that the EGFR-TKIs produce gains in progression-free survival and overall response rates, although only in patients whose tumors harbor activating mutations in the EGFR gene. Clinical trials have also shown EGFR-TKIs to be effective as second- and third-line therapies in advanced NSCLC. Here, we review the main aspects of EGFR pathway activation in NSCLC, underscore the importance of correctly identifying activating mutations in the EGFR gene, and discuss the main outcomes of EGFR-TKI treatment in NSCLC.

  4. Identifying activating mutations in the EGFR gene: prognostic and therapeutic implications in non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Gabriel Lima Lopes

    2015-08-01

    Full Text Available AbstractLung cancer is the leading cause of cancer-related deaths worldwide. Promising new therapies have recently emerged from the development of molecular targeted drugs; particularly promising are those blocking the signal transduction machinery of cancer cells. One of the most widely studied cell signaling pathways is that of EGFR, which leads to uncontrolled cell proliferation, increased cell angiogenesis, and greater cell invasiveness. Activating mutations in the EGFR gene (deletions in exon 19 and mutation L858R in exon 21, first described in 2004, have been detected in approximately 10% of all non-squamous non-small cell lung cancer (NSCLC patients in Western countries and are the most important predictors of a response to EGFR tyrosine-kinase inhibitors (EGFR-TKIs. Studies of the EGFR-TKIs gefitinib, erlotinib, and afatinib, in comparison with platinum-based regimens, as first-line treatments in chemotherapy-naïve patients have shown that the EGFR-TKIs produce gains in progression-free survival and overall response rates, although only in patients whose tumors harbor activating mutations in the EGFR gene. Clinical trials have also shown EGFR-TKIs to be effective as second- and third-line therapies in advanced NSCLC. Here, we review the main aspects of EGFR pathway activation in NSCLC, underscore the importance of correctly identifying activating mutations in the EGFR gene, and discuss the main outcomes of EGFR-TKI treatment in NSCLC.

  5. Identifying activating mutations in the EGFR gene: prognostic and therapeutic implications in non-small cell lung cancer *

    Science.gov (United States)

    Lopes, Gabriel Lima; Vattimo, Edoardo Filippo de Queiroz; de Castro, Gilberto

    2015-01-01

    Abstract Lung cancer is the leading cause of cancer-related deaths worldwide. Promising new therapies have recently emerged from the development of molecular targeted drugs; particularly promising are those blocking the signal transduction machinery of cancer cells. One of the most widely studied cell signaling pathways is that of EGFR, which leads to uncontrolled cell proliferation, increased cell angiogenesis, and greater cell invasiveness. Activating mutations in the EGFR gene (deletions in exon 19 and mutation L858R in exon 21), first described in 2004, have been detected in approximately 10% of all non-squamous non-small cell lung cancer (NSCLC) patients in Western countries and are the most important predictors of a response to EGFR tyrosine-kinase inhibitors (EGFR-TKIs). Studies of the EGFR-TKIs gefitinib, erlotinib, and afatinib, in comparison with platinum-based regimens, as first-line treatments in chemotherapy-naïve patients have shown that the EGFR-TKIs produce gains in progression-free survival and overall response rates, although only in patients whose tumors harbor activating mutations in the EGFR gene. Clinical trials have also shown EGFR-TKIs to be effective as second- and third-line therapies in advanced NSCLC. Here, we review the main aspects of EGFR pathway activation in NSCLC, underscore the importance of correctly identifying activating mutations in the EGFR gene, and discuss the main outcomes of EGFR-TKI treatment in NSCLC. PMID:26398757

  6. De novo activating epidermal growth factor mutations (EGFR) in small-cell lung cancer.

    Science.gov (United States)

    Thai, Alesha; Chia, Puey L; Russell, Prudence A; Do, Hongdo; Dobrovic, Alex; Mitchell, Paul; John, Thomas

    2017-09-01

    In Australia, mutations in epidermal growth factor mutations (EGFR) occur in 15% of patients diagnosed with non-small-cell lung cancer and are found with higher frequency in female, non-smokers of Asian ethnicity. Activating mutations in the EGFR gene are rarely described in SCLC. We present two cases of de novo EGFR mutations in patients with SCLC detected in tissue and in plasma cell free DNA, both of whom were of Asian ethnicity and never-smokers. These two cases add to the growing body of evidence suggesting that screening for EGFR mutations in SCLC should be considered in patients with specific clinical features. © 2017 Royal Australasian College of Physicians.

  7. Identification of the zinc finger 216 (ZNF216) in human carcinoma cells: a potential regulator of EGFR activity

    Science.gov (United States)

    Mincione, Gabriella; Di Marcantonio, Maria Carmela; Tarantelli, Chiara; Savino, Luca; Ponti, Donatella; Marchisio, Marco; Lanuti, Paola; Sancilio, Silvia; Calogero, Antonella; Di Pietro, Roberta; Muraro, Raffaella

    2016-01-01

    Epidermal Growth Factor Receptor (EGFR), a member of the ErbB family of receptor tyrosine kinase (RTK) proteins, is aberrantly expressed or deregulated in tumors and plays pivotal roles in cancer onset and metastatic progression. ZNF216 gene has been identified as one of Immediate Early Genes (IEGs) induced by RTKs. Overexpression of ZNF216 protein sensitizes 293 cell line to TNF-α induced apoptosis. However, ZNF216 overexpression has been reported in medulloblastomas and metastatic nasopharyngeal carcinomas. Thus, the role of this protein is still not clearly understood. In this study, the inverse correlation between EGFR and ZNF216 expression was confirmed in various human cancer cell lines differently expressing EGFR. EGF treatment of NIH3T3 cells overexpressing both EGFR and ZNF216 (NIH3T3-EGFR/ZNF216), induced a long lasting activation of EGFR in the cytosolic fraction and an accumulation of phosphorylated EGFR (pEGFR) more in the nuclear than in the cytosolic fraction compared to NIH3T3-EGFR cells. Moreover, EGF was able to stimulate an increased expression of ZNF216 in the cytosolic compartment and its nuclear translocation in a time-dependent manner in NIH3T3-EGFR/ZNF216. A similar trend was observed in A431 cells endogenously expressing the EGFR and transfected with Znf216. The increased levels of pEGFR and ZNF216 in the nuclear fraction of NIH3T3-EGFR/ZNF216 cells were paralleled by increased levels of phospho-MAPK and phospho-Akt. Surprisingly, EGF treatment of NIH3T3-EGFR/ZNF216 cells induced a significant increase of apoptosis thus indicating that ZNF216 could sensitize cells to EGF-induced apoptosis and suggesting that it may be involved in the regulation and effects of EGFR signaling. PMID:27732953

  8. Anti-tumor activity of high-dose EGFR tyrosine kinase inhibitor and sequential docetaxel in wild type EGFR non-small cell lung cancer cell nude mouse xenografts

    OpenAIRE

    Tang, Ning; Zhang, Qianqian; Fang, Shu; Han, Xiao; Wang, Zhehai

    2016-01-01

    Treatment of non-small-cell lung cancer (NSCLC) with wild-type epidermal growth factor receptor (EGFR) is still a challenge. This study explored antitumor activity of high-dose icotinib (an EGFR tyrosine kinase inhibitor) plus sequential docetaxel against wild-type EGFR NSCLC cells-generated nude mouse xenografts. Nude mice were subcutaneously injected with wild-type EGFR NSCLC A549 cells and divided into different groups for 3-week treatment. Tumor xenograft volumes were monitored and record...

  9. 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

    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....... 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...

  10. 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

    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...... 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...

  11. Activation of a Neospora caninum EGFR-Like Kinase Facilitates Intracellular Parasite Proliferation

    Directory of Open Access Journals (Sweden)

    Xiaoxia Jin

    2017-10-01

    Full Text Available The Apicomplexan parasite Neospora caninum, an obligate intracellular protozoan, causes serious diseases in a number of mammalian species, especially in cattle. Infection with N. caninum is associated with abortions in both dairy and beef cattle worldwide which have a major economic impact on the cattle industry. However, the mechanism by which N. caninum proliferates within host cells is poorly understood. Epidermal growth factor receptor (EGFR is a protein kinase ubiquitously expressed, present on cell surfaces in numerous species, which has been confirmed to be essential in signal transduction involved in cell growth, proliferation, survival, and many other intracellular processes. However, the presence of EGFR in N. caninum and its role in N. caninum proliferation remain unclear. In the present study, we identified a putative EGFR-like kinase in N. caninum, which could be activated in tachyzoites by infection or treatment with rNcMIC3 [containing four epidermal growth factor (EGF domains] or human EGF. Blockade of EGFR-like in tachyzoites by AG1478 significantly reduced parasite proliferation in host cells. Our data suggested that the activation of tachyzoite EGFR-like might facilitate the intracellular proliferation of N. caninum.

  12. Co-activation of STAT3 and YES-Associated Protein 1 (YAP1) Pathway in EGFR-Mutant NSCLC

    DEFF Research Database (Denmark)

    Chaib, Imane; Karachaliou, Niki; Pilotto, Sara

    2017-01-01

    Background: The efficacy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in EGFR-mutant non-small cell lung cancer (NSCLC) is limited by adaptive activation of cell survival signals. We hypothesized that both signal transducer and activator of transcription 3 (STAT3) ...

  13. Impact of active smoking on survival of patients with metastatic lung adenocarcinoma harboring an epidermal growth factor receptor (EGFR mutation

    Directory of Open Access Journals (Sweden)

    Bulent Erdogan

    2016-11-01

    Full Text Available Lung cancer in smokers and non-smokers demonstrates distinct genetic profiles, and cigarette smoking affects epidermal growth factor receptor (EGFR function and causes secondary EGFR tyrosine kinase resistance. We evaluated the effect of active smoking in patients with metastatic lung adenocarcinoma. A total of 132 metastatic lung adenocarcinoma patients, diagnosed between 2008 and 2013, with known EGFR mutation status, were evaluated retrospectively. Among these patients, 40 had an activating EGFR mutation. Patients who continued smoking during the treatment were defined as active smokers. Former smokers and never smokers were together defined as non-smokers. The outcomes of the treatment in relation to the EGFR mutation and smoking status were evaluated. The median follow-up time was 10.5 months. The overall response rate for the first-line therapy was significantly higher among the EGFR-mutant patients (p = 0.01, however, smoking status had no impact on the response rate (p = 0.1. The EGFR-mutant active smokers progressed earlier than the non-smokers (p < 0.01. The overall survival (OS of the non-smokers and patients treated with erlotinib was significantly longer (p = 0.02 and p = 0.01, respectively. Smoking status did not affect the OS in EGFR wild type tumors (p = 0.49 but EGFR-mutant non-smokers had a longer OS than the active smokers (p = 0.01.The active smokers treated with erlotinib had poorer survival than the non-smokers (p = 0.03. Multivariate analysis of EGFR-mutant patients showed that erlotinib treatment at any line and non-smoking were independent prognostic factors for the OS (p = 0.04 and p = 0.01, respectively. Smoking during treatment is a negative prognostic factor in metastatic lung adenocarcinoma with an EGFR mutation.

  14. Impact of active smoking on survival of patients with metastatic lung adenocarcinoma harboring an epidermal growth factor receptor (EGFR) mutation.

    Science.gov (United States)

    Erdogan, Bulent; Kodaz, Hilmi; Karabulut, Senem; Cinkaya, Ahmet; Tozkir, Hilmi; Tanriverdi, Ozgur; Cabuk, Devrim; Hacioglu, Muhammed Bekir; Turkmen, Esma; Hacibekiroglu, Ilhan; Uzunoglu, Sernaz; Cicin, Irfan

    2016-11-10

    Lung cancer in smokers and non-smokers demonstrates distinct genetic profiles, and cigarette smoking affects epidermal growth factor receptor (EGFR) function and causes secondary EGFR tyrosine kinase resistance. We evaluated the effect of active smoking in patients with metastatic lung adenocarcinoma. A total of 132 metastatic lung adenocarcinoma patients, diagnosed between 2008 and 2013, with known EGFR mutation status, were evaluated retrospectively. Among these patients, 40 had an activating EGFR mutation. Patients who continued smoking during the treatment were defined as active smokers. Former smokers and never smokers were together defined as non-smokers. The outcomes of the treatment in relation to the EGFR mutation and smoking status were evaluated. The median follow-up time was 10.5 months. The overall response rate for the first-line therapy was significantly higher among the EGFR-mutant patients (p = 0.01), however, smoking status had no impact on the response rate (p = 0.1). The EGFR-mutant active smokers progressed earlier than the non-smokers (p non-smokers and patients treated with erlotinib was significantly longer (p = 0.02 and p = 0.01, respectively). Smoking status did not affect the OS in EGFR wild type tumors (p = 0.49) but EGFR-mutant non-smokers had a longer OS than the active smokers (p = 0.01).The active smokers treated with erlotinib had poorer survival than the non-smokers (p = 0.03). Multivariate analysis of EGFR-mutant patients showed that erlotinib treatment at any line and non-smoking were independent prognostic factors for the OS (p = 0.04 and p = 0.01, respectively). Smoking during treatment is a negative prognostic factor in metastatic lung adenocarcinoma with an EGFR mutation.

  15. Profiling EGFR activity in head and neck squamous cell carcinoma by using a novel layered membrane Western blot technology.

    Science.gov (United States)

    Patel, Vyomesh; Ramesh, Arun; Traicoff, June L; Baibakov, Galina; Emmert-Buck, Michael R; Gutkind, J Silvio; Knezevic, Vladimir

    2005-05-01

    Given the role of epidermal growth factor receptor (EGFR) in head and neck squamous cell carcinomas (HNSCC), several rational approaches have now been utilized to abrogate tyrosine kinase activity and its disengagement from downstream signal transducers. Monitoring the activity of these molecules could potentially be useful to determine not only drug efficacy but also to identify HNSCC patients most likely to benefit from this type of therapy. In this study we have used a novel high throughput multi-layered Western blotting (MLWestern) method that allows the detection of multiple proteins from a single experiment in order to characterize key components in the EGFR signaling pathway in HNSCC cells. Total and activated forms of EGFR and the downstream effectors, Erk and Akt were readily detected in HNSCC cells, where in the control cells (HaCaT) these proteins could only be detected in EGF stimulated cells. Results from conventional Western blot and MLWestern were comparable. Clustering analysis of protein expression revealed similarities in cellular response between some of the cell lines indicative of similarities in their biological response. The data indicate that MLWestern can be potentially applied to identify molecular targets that could be used for rational therapeutic intervention strategies.

  16. 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.

  17. CCR 20th anniversary commentary: a chimeric antibody, C225, inhibits EGFR activation and tumor growth.

    Science.gov (United States)

    Mendelsohn, John; Prewett, Marie; Rockwell, Patricia; Goldstein, Neil I

    2015-01-15

    Murine mAb 225 was effective against the EGFR tyrosine kinase and inhibited tumor growth in preclinical studies. A phase I trial showed safety, tumor localization, and satisfactory pharmacokinetics. Human:murine chimeric C225 retained biologic activity, which was essential for the conduct of subsequent combination therapy trials and eventual regulatory approval. ©2015 American Association for Cancer Research.

  18. The Drosophila Arf GEF Steppke controls MAPK activation in EGFR signaling.

    Science.gov (United States)

    Hahn, Ines; Fuss, Bernhard; Peters, Annika; Werner, Tamara; Sieberg, Andrea; Gosejacob, Dominic; Hoch, Michael

    2013-06-01

    Guanine nucleotide exchange factors (GEFs) of the cytohesin protein family are regulators of GDP/GTP exchange for members of the ADP ribosylation factor (Arf) of small GTPases. They have been identified as modulators of various receptor tyrosine kinase signaling pathways including the insulin, the vascular epidermal growth factor (VEGF) and the epidermal growth factor (EGF) pathways. These pathways control many cellular functions, including cell proliferation and differentiation, and their misregulation is often associated with cancerogenesis. In vivo studies on cytohesins using genetic loss of function alleles are lacking, however, since knockout mouse models are not available yet. We have recently identified mutants for the single cytohesin Steppke (Step) in Drosophila and we could demonstrate an essential role of Step in the insulin signaling cascade. In the present study, we provide in vivo evidence for a role of Step in EGFR signaling during wing and eye development. By analyzing step mutants, transgenic RNA interference (RNAi) and overexpression lines for tissue specific as well as clonal analysis, we found that Step acts downstream of the EGFR and is required for the activation of mitogen-activated protein kinase (MAPK) and the induction of EGFR target genes. We further demonstrate that step transcription is induced by EGFR signaling whereas it is negatively regulated by insulin signaling. Furthermore, genetic studies and biochemical analysis show that Step interacts with the Connector Enhancer of KSR (CNK). We propose that Step may be part of a larger signaling scaffold coordinating receptor tyrosine kinase-dependent MAPK activation.

  19. 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

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

    International Nuclear Information System (INIS)

    Berndt, Alexander; Büttner, Robert; Gühne, Stefanie; Gleinig, Anna; Richter, Petra; Chen, Yuan; Franz, Marcus; Liebmann, Claus

    2014-01-01

    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 TGF , FCM PDGF ) were used to stimulate PE/CA-PJ15 OSCC cells. Results were compared to the effect of conditioned media of non-stimulated fibroblasts (FCM B ). FCM 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 TGF ≫FCM 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 TGF >FCM 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 as sign of EMT. • Results qualify

  1. Nicotine enhances proliferation, migration, and radioresistance of human malignant glioma cells through EGFR activation

    International Nuclear Information System (INIS)

    Khalil, A.A.; Jameson, M.J.; Broaddus, W.C.; Lin, P.S.; Chung, T.D.

    2013-01-01

    It has been suggested that continued tobacco use during radiation therapy contributes to maintenance of neoplastic growth despite treatment with radiation. Nicotine is a cigarette component that is an established risk factor for many diseases, neoplastic and otherwise. The hypothesis of this work is that nicotine promotes the proliferation, migration, and radioresistance of human malignant glioma cells. The effect of nicotine on cellular proliferation, migration, signaling, and radiation sensitivity were evaluated for malignant glioma U87 and GBM12 cells by use of the AlamarBlue, scratch healing, and clonogenic survival assays. Signal transduction was assessed by immunoblotting for activated EGFR, extracellular regulated kinase (ERK), and AKT. At concentrations comparable with those found in chronic smokers, nicotine induced malignant glioma cell migration, growth, colony formation, and radioresistance. Nicotine increased phosphorylation of EGFR tyr992 , AKT ser473 , and ERK. These molecular effects were reduced by pharmacological inhibitors of EGFR, PI3K, and MEK. It was therefore concluded that nicotine stimulates the malignant behavior of glioma cells in vitro by activation of the EGFR and downstream AKT and ERK pathways. (author)

  2. Phosphorylated EGFR expression may predict outcome of EGFR-TKIs therapy for the advanced NSCLC patients with wild-type EGFR

    Directory of Open Access Journals (Sweden)

    Wang Fen

    2012-08-01

    Full Text Available Abstract Background EGFR mutation is a strong predictive factor of EGFR-TKIs therapy. However, at least 10% of patients with EGFR wild-type are responsive to TKIs, suggesting that other determinants of outcome besides EGFR mutation might exist. We hypothesized that activation of phosphorylated EGFR could be a potential predictive biomarker to EGFR-TKIs treatment among patients in wild-type EGFR. Method Total of 205 stage IIIb and IV NSCLC patients, tissue samples of whom were available for molecular analysis, were enrolled in this study. The phosphorylation of EGFR at tyrosine 1068 (pTyr1068 and 1173 (pTyr1173 were assessed by immunohistochemistry, and EGFR mutations were detected by denaturing high performance liquid chromatograph (DHPLC. Results Among 205 patients assessable for EGFR mutation and phosphorylation analysis, 92 (44.9% were EGFR mutant and 165 patients (57.6% had pTyr1173 expression. Superior progression-free survival (PFS was seen after EGFR-TKIs therapy in patients with pTyr1068 expression compared to pTyr1068 negative ones (median PFS 7.0 months vs. 1.2 months, P P = 0.016. In subgroup of patients with wild-type EGFR, pTyr1068 expression positive ones had a significantly prolonged PFS (4.2 months vs.1.2 months P  Conclusion pTyr1068 may be a predictive biomarker for screening the population for clinical response to EGFR-TKIs treatment; especially for patients with wild-type EGFR.

  3. NF-κB-dependent transcriptional upregulation of cyclin D1 exerts cytoprotection against hypoxic injury upon EGFR activation

    International Nuclear Information System (INIS)

    Chen, Zhi-Dong; Xu, Liang; Tang, Kan-Kai; Gong, Fang-Xiao; Liu, Jing-Quan; Ni, Yin; Jiang, Ling-Zhi; Hong, Jun; Han, Fang; Li, Qian; Yang, Xiang-Hong; Sun, Ren-Hua; Mo, Shi-Jing

    2016-01-01

    Apoptosis of neural cells is one of the main pathological features in hypoxic/ischemic brain injury. Nuclear factor-κB (NF-κB) might be a potential therapeutic target for hypoxic/ischemic brain injury since NF-κB has been found to be inactivated after hypoxia exposure, yet the underlying molecular mechanisms of NF-κB inactivation are largely unknown. Here we report that epidermal growth factor receptor (EGFR) activation prevents neuron-like PC12 cells apoptosis in response to hypoxia via restoring NF-κB-dependent transcriptional upregulation of cyclin D1. Functionally, EGFR activation by EGF stimulation mitigates hypoxia-induced PC12 cells apoptosis in both dose- and time-dependent manner. Of note, EGFR activation elevates IKKβ phosphorylation, increases IκBα ubiquitination, promotes P65 nuclear translocation and recruitment at cyclin D1 gene promoter as well as upregulates cyclin D1 expression. EGFR activation also abrogates the decrease of IKKβ phosphorylation, reduction of IκBα ubiquitination, blockade of P65 nuclear translocation and recruitment at cyclin D1 gene promoter as well as downregulation of cyclin D1 expression induced by hypoxia. Furthermore, NF-κB-dependent upregulation of cyclin D1 is instrumental for the EGFR-mediated cytoprotection against hypoxic apoptosis. In addition, the dephosphorylation of EGFR induced by either EGF siRNA transfection or anti-HB-EGF neutralization antibody treatment enhances hypoxic cytotoxicity, which are attenuated by EGF administration. Our results highlight the essential role of NF-κB-dependent transcriptional upregulation of cyclin D1 in EGFR-mediated cytoprotective effects under hypoxic preconditioning and support further investigation of EGF in clinical trials of patients with hypoxic/ischemic brain injury. - Highlights: • EGFR activation significantly decreases hypoxia-induced PC12 cells injury. • EGFR activation abrogates the transcriptional repression of cyclin D1 induced by hypoxia in a NF

  4. NF-κB-dependent transcriptional upregulation of cyclin D1 exerts cytoprotection against hypoxic injury upon EGFR activation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Zhi-Dong [Department of Critical Care Medicine, The First Affiliated Hospital of Huzhou Normal College, Huzhou 313000, Zhejiang (China); Xu, Liang [Department of Critical Care Medicine, Zhejiang Provincial People’s Hospital, Hangzhou 310000, Zhejiang (China); Tang, Kan-Kai [Department of Critical Care Medicine, The First Affiliated Hospital of Huzhou Normal College, Huzhou 313000, Zhejiang (China); Gong, Fang-Xiao; Liu, Jing-Quan; Ni, Yin; Jiang, Ling-Zhi; Hong, Jun; Han, Fang; Li, Qian; Yang, Xiang-Hong [Department of Critical Care Medicine, Zhejiang Provincial People’s Hospital, Hangzhou 310000, Zhejiang (China); Sun, Ren-Hua, E-mail: jqin168@hotmail.com [Department of Critical Care Medicine, Zhejiang Provincial People’s Hospital, Hangzhou 310000, Zhejiang (China); Mo, Shi-Jing, E-mail: msj860307@163.com [Department of Critical Care Medicine, Zhejiang Provincial People’s Hospital, Hangzhou 310000, Zhejiang (China)

    2016-09-10

    Apoptosis of neural cells is one of the main pathological features in hypoxic/ischemic brain injury. Nuclear factor-κB (NF-κB) might be a potential therapeutic target for hypoxic/ischemic brain injury since NF-κB has been found to be inactivated after hypoxia exposure, yet the underlying molecular mechanisms of NF-κB inactivation are largely unknown. Here we report that epidermal growth factor receptor (EGFR) activation prevents neuron-like PC12 cells apoptosis in response to hypoxia via restoring NF-κB-dependent transcriptional upregulation of cyclin D1. Functionally, EGFR activation by EGF stimulation mitigates hypoxia-induced PC12 cells apoptosis in both dose- and time-dependent manner. Of note, EGFR activation elevates IKKβ phosphorylation, increases IκBα ubiquitination, promotes P65 nuclear translocation and recruitment at cyclin D1 gene promoter as well as upregulates cyclin D1 expression. EGFR activation also abrogates the decrease of IKKβ phosphorylation, reduction of IκBα ubiquitination, blockade of P65 nuclear translocation and recruitment at cyclin D1 gene promoter as well as downregulation of cyclin D1 expression induced by hypoxia. Furthermore, NF-κB-dependent upregulation of cyclin D1 is instrumental for the EGFR-mediated cytoprotection against hypoxic apoptosis. In addition, the dephosphorylation of EGFR induced by either EGF siRNA transfection or anti-HB-EGF neutralization antibody treatment enhances hypoxic cytotoxicity, which are attenuated by EGF administration. Our results highlight the essential role of NF-κB-dependent transcriptional upregulation of cyclin D1 in EGFR-mediated cytoprotective effects under hypoxic preconditioning and support further investigation of EGF in clinical trials of patients with hypoxic/ischemic brain injury. - Highlights: • EGFR activation significantly decreases hypoxia-induced PC12 cells injury. • EGFR activation abrogates the transcriptional repression of cyclin D1 induced by hypoxia in a NF

  5. PGE2 mediates EGFR internalization and nuclear translocation via caveolin endocytosis promoting its transcriptional activity and proliferation in human NSCLC cells.

    Science.gov (United States)

    Bazzani, Lorenzo; Donnini, Sandra; Giachetti, Antonio; Christofori, Gerhard; Ziche, Marina

    2018-03-13

    Prostaglandin E 2 (PGE 2 ) contributes to tumor progression by promoting cancer cell growth, invasion and by creating a favorable pro-tumor microenvironment. PGE 2 has been reported to transactivate and internalize into the nucleus receptor tyrosine kinases such as Epidermal growth factor receptor (EGFR), thereby supporting tumor progression. Here we demonstrate that in non-small cell lung carcinoma (NSCLC) cells, PGE 2 induces EGFR nuclear translocation via different dynamin-dependent endocytic pathways, promotes the formation of an EGFR-STAT3 complex, affects nuclear EGFR target gene expression and mediates tumor cell proliferation. Indeed, we find that PGE 2 induces EGFR internalization and consequent nuclear import through Clathrin- and Caveolin-mediated endocytosis and through the interaction of EGFR with Importin β1. Within the nucleus, EGFR forms a complex with STAT3, an event blocked by ablation of Clathrin Heavy Chain or Caveolin-1. The combination of EGF and PGE 2 prolongs nuclear EGFR transcriptional activity manifested by the upregulation of CCND1 , PTGS2 , MYC and NOS2 mRNA levels and potentiates nuclear EGFR-induced NSCLC cell proliferation. Additionally, NSCLC patients with high expression of a nuclear EGFR gene signature display shorter survival times than those with low expression, thus showing a putative correlation between nuclear EGFR and poor prognosis in NSCLC. Together, our findings indicate a complex mechanism underlying PGE 2 -induced EGF/EGFR signaling and transcriptional control, which plays a key role in cancer progression.

  6. NF-κB signaling is activated and confers resistance to apoptosis in three-dimensionally cultured EGFR-mutant lung adenocarcinoma cells

    International Nuclear Information System (INIS)

    Sakuma, Yuji; Yamazaki, Yukiko; Nakamura, Yoshiyasu; Yoshihara, Mitsuyo; Matsukuma, Shoichi; Koizume, Shiro; Miyagi, Yohei

    2012-01-01

    Highlights: ► EGFR-mutant cells in 3D culture resist EGFR inhibition compared with suspended cells. ► Degradation of IκB and activation of NF-κB are observed in 3D-cultured cells. ► Inhibiting NF-κB 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 IκBα, the inhibitor of nuclear factor (NF)-κB, was observed only in the 3D-cultured cells, leading to an increase in the activation of NF-κB. Moreover, the inhibition of NF-κB with pharmacological inhibitors enhanced EGFR TKI-induced apoptosis in 3D-cultured EGFR-mutant cells. These results suggest that inhibition of NF-κB signaling would render ECM-adherent EGFR-mutant lung adenocarcinoma cells in vivo more susceptible to EGFR TKI-induced cell death.

  7. Antitumor Efficacy of Dual Blockade of EGFR Signaling by Osimertinib in Combination With Selumetinib or Cetuximab in Activated EGFR Human NCLC Tumor Models.

    Science.gov (United States)

    Della Corte, Carminia Maria; Ciaramella, Vincenza; Cardone, Claudia; La Monica, Silvia; Alfieri, Roberta; Petronini, Pier Giorgio; Malapelle, Umberto; Vigliar, Elena; Pepe, Francesco; Troncone, Giancarlo; Castellone, Maria Domenica; Troiani, Teresa; Martinelli, Erika; Ciardiello, Fortunato; Morgillo, Floriana

    2018-03-08

    Osimertinib showed great clinical efficacy for activated-EGFR NCLC patient treatment. The aim of this work was to test the efficacy of a complete EGFR-inhibition by osimertinib plus the monoclonal antibody cetuximab or the MEK1/2-inhibitor selumetinib in EGFR-mutated NCLC in vivo models. We evaluated combinations of osimertinib plus selumetinib/cetuximab in HCC827 (E746-A759del/T790M-), H1975 (L858R/T790M+), and PC9-T790M (E746-A759del /T790M+) xenografts in second-line therapy after the development of resistance to osimertinib, and in first-line therapy, and we explored mechanisms of resistance to these treatments. The addition of selumetinib or cetuximab to osimertinib in second-line therapy reverted the sensibility to osimertinib in the majority of mice, with a response rate (RR) of 50% to 80%, and a median progression-free survival (mPFS) of first- plus second-line of therapy of 28 weeks. The early use of combinations in first-line therapy increased the RR to 90%, with an mPFS not reached in all combination arms in the three xenografts models, with a statistically significant superiority (p < 0.005) as compared to osimertinib, achieving in first-line therapy an mPFS time of 17 to 18 weeks. Moreover, in ex vivo primary cell cultures obtained from osimertinib plus selumetinib-resistant tumors, we found Hedgehog pathway activation and we showed that therapy with an SMO inhibitor plus osimertinib and selumetinib inhibited proliferation and migratory and invasive properties of resistant cells. We showed that a dual vertical EGFR blockade with osimertinib plus selumetinib/cetuximab is a novel effective therapeutic option in EGFR-mutated NCLC and that hedgehog pathway activation and its interplay with MAPK is involved in resistance to these combination treatments. Copyright © 2018 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

  8. Epithelial–mesenchymal-transition induced by EGFR activation interferes with cell migration and response to irradiation and cetuximab in head and neck cancer cells

    International Nuclear Information System (INIS)

    Holz, Carmen; Niehr, Franziska; Boyko, Mariya; Hristozova, Tsvetana; Distel, Luitpold; Budach, Volker; Tinhofer, Ingeborg

    2011-01-01

    Background and purpose: The role of epithelial–mesenchymal transition (EMT) in the poor outcome of EGFR-overexpressing SCCHN was evaluated. Material and methods: SCCHN cell lines were characterized for their cell morphology and expression of EGFR and the EMT-associated factors E-cadherin, vimentin and Snail1. The migratory potential of cells was assessed in motility assays. Response to irradiation and cetuximab was determined using clonogenic survival assays. Results: High basal expression of E-cadherin but low to absent vimentin expression could be observed in all SCCHN cell lines. Although E-cadherin expression levels did not change after treatment with EGF we observed a significant change in cell morphology resembling EMT. SCCHN cells with high basal levels of Snail1 resulting from constitutive EGFR activation were characterized by mesenchymal-like morphology, elevated migratory potential, reduced sensitivity to irradiation and cetuximab but increased sensitivity to the combined treatment. Conclusions: Autocrine activation of EGFR leading to EMT is associated with a metastatic phenotype and reduced sensitivity of SCCHN cells to single-modality treatment with cetuximab or irradiation. The potential of Snail1 as biomarker for selection of patients who will mostly benefit from a combination of cetuximab and radiotherapy has to be evaluated in future clinical studies.

  9. TWIST1 a new determinant of epithelial to mesenchymal transition in EGFR mutated lung adenocarcinoma.

    Directory of Open Access Journals (Sweden)

    Karine Pallier

    Full Text Available Metastasis is a multistep process and the main cause of mortality in lung cancer patients. We previously showed that EGFR mutations were associated with a copy number gain at a locus encompassing the TWIST1 gene on chromosome 7. TWIST1 is a highly conserved developmental gene involved in embryogenesis that may be reactivated in cancers promoting both malignant conversion and cancer progression through an epithelial to mesenchymal transition (EMT. The aim of this study was to investigate the possible implication of TWIST1 reactivation on the acquisition of a mesenchymal phenotype in EGFR mutated lung cancer. We studied a series of consecutive lung adenocarcinoma from Caucasian non-smokers for which surgical frozen samples were available (n = 33 and showed that TWIST1 expression was linked to EGFR mutations (P<0.001, to low CDH1 expression (P<0.05 and low disease free survival (P = 0.044. To validate that TWIST1 is a driver of EMT in EGFR mutated lung cancer, we used five human lung cancer cell lines and demonstrated that EMT and the associated cell mobility were dependent upon TWIST1 expression in cells with EGFR mutation. Moreover a decrease of EGFR pathway stimulation through EGF retrieval or an inhibition of TWIST1 expression by small RNA technology reversed the phenomenon. Collectively, our in vivo and in vitro findings support that TWIST1 collaborates with the EGF pathway in promoting EMT in EGFR mutated lung adenocarcinoma and that large series of EGFR mutated lung cancer patients are needed to further define the prognostic role of TWIST1 reactivation in this subgroup.

  10. Antibacterial and EGFR-Tyrosine Kinase Inhibitory Activities of Polyhydroxylated Xanthones from Garcinia succifolia

    Directory of Open Access Journals (Sweden)

    Susawat Duangsrisai

    2014-11-01

    Full Text Available Chemical investigation of the methanol extract of the wood of Garcinia succifolia Kurz (Clusiaceae led to the isolation of 1,5-dihydroxyxanthone (1, 1,7-dihydroxyxanthone (2, 1,3,7-trihydroxyxanthone (3, 1,5,6-trihydroxyxanthone (4, 1,6,7-trihydroxyxanthone (5, and 1,3,6,7-tetrahydroxyxanthone (6. All of the isolated xanthones were evaluated for their antibacterial activity against bacterial reference strains, two Gram-positive (Staphylococcus aureus ATTC 25923, Bacillus subtillis ATCC 6633 and two Gram-negative (Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853, and environmental drug-resistant isolates (S. aureus B1, Enteroccoccus faecalis W1, and E. coli G1, as well as for their epidermal growth factor receptor (EGFR of tyrosine kinase inhibitory activity. Only 1,5,6-trihydroxy-(4, 1,6,7-trihydroxy-(5, and 1,3,6,7-tetrahydroxyxanthones (6 exhibited antibacterial activity against Gram-positive bacteria, however none was active against vancomycin-resistant E. faecalis. Additionally, 1,7-dihydroxyxanthone (2 showed synergism with oxacillin, but not with ampicillin. On the other hand, only 1,5-dihydroxyxanthone (1 and 1,7-dihydroxyxanthone (2 were found to exhibit the EGFR-tyrosine kinase inhibitory activity, with IC50 values of 90.34 and 223 nM, respectively.

  11. Celecoxib induces proliferation and Amphiregulin production in colon subepithelial myofibroblasts, activating erk1-2 signaling in synergy with EGFR.

    Science.gov (United States)

    Benelli, Roberto; Venè, Roberta; Minghelli, Simona; Carlone, Sebastiano; Gatteschi, Beatrice; Ferrari, Nicoletta

    2013-01-01

    The COX-2 inhibitor Celecoxib, tested in phase III trials for the prevention of sporadic colon adenomas, reduced the appearance of new adenomas, but was unable to affect the incidence of colon cancer. Moreover the 5years follow-up showed that patients discontinuing Celecoxib treatment had an increased incidence of adenomas as compared to the placebo arm. In the APC(min/+) mouse model short term treatment with Celecoxib reduced gut adenomas, but a prolonged administration of the drug induced fibroblast activation and intestinal fibrosis with a final tumor burden. The way Celecoxib could directly activate human colon myofibroblasts (MF) has not yet been investigated. We found that MF are activated by non toxic doses of Celecoxib. Celecoxib induces erk1-2 and Akt phosphorylation within 5'. This short term activation is apparently insufficient to cause phenotypic changes, but the contemporary triggering of EGFR causes an impressive synergic effect inducing MF proliferation and the neo-expression and release of Amphiregulin (AREG), a well known EGFR agonist involved in colon cancer progression. As a confirm to these observations, the erk inhibitor U0126 and the EGFR inhibitors Tyrphostin and Cetuximab were able to contrast AREG induction. Our data provide evidence that Celecoxib directly activates MF empowering EGFR signaling. According to these results the association with EGFR (or erk1-2) inhibitors could abolish the off-target activity of Celecoxib, possibly extending the potential of this drug for colon cancer prevention. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  12. Enhanced EGFR Targeting Activity of Plasmonic Nanostructures with Engineered GE11 Peptide.

    Science.gov (United States)

    Biscaglia, Francesca; Rajendran, Senthilkumar; Conflitti, Paolo; Benna, Clara; Sommaggio, Roberta; Litti, Lucio; Mocellin, Simone; Bocchinfuso, Gianfranco; Rosato, Antonio; Palleschi, Antonio; Nitti, Donato; Gobbo, Marina; Meneghetti, Moreno

    2017-12-01

    Plasmonic nanostructures show important properties for biotechnological applications, but they have to be guided on the target for exploiting their potentialities. Antibodies are the natural molecules for targeting. However, their possible adverse immunogenic activity and their cost have suggested finding other valid substitutes. Small molecules like peptides can be an alternative source of targeting agents, even if, as single molecules, their binding affinity is usually not very good. GE11 is a small dodecapeptide with specific binding to the epidermal growth factor receptor (EGFR) and low immunogenicity. The present work shows that thousands of polyethylene glycol (PEG) chains modified with lysines and functionalized with GE11 on clusters of naked gold nanoparticles, obtained by laser ablation in water, achieves a better targeting activity than that recorded with nanoparticles decorated with the specific anti-EGFR antibody Cetuximab (C225). The insertion of the cationic spacer between the polymeric part of the ligand and the targeting peptide allows for a proper presentation of GE11 on the surface of the nanosystems. Surface enhanced resonance Raman scattering signals of the plasmonic gold nanoparticles are used for quantifying the targeting activity. Molecular dynamic calculations suggest that subtle differences in the exposition of the peptide on the PEG sea are important for the targeting activity. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. 4-Hydroxynonenal activates Src through a non-canonical pathway that involves EGFR/PTP1B

    Science.gov (United States)

    Zhang, Hongqiao; Forman, Henry Jay

    2015-01-01

    Src, a non-receptor protein tyrosine kinase involved in many biological processes, can be activated through both redox-dependent and independent mechanisms. 4-Hydroxy-2-nonenal (HNE) is a lipid peroxidation product that is increased in pathophysiological conditions associated with Src activation. This study examined how HNE activates human c-Src. In the canonical pathway Src activation is initiated by dephosphorylation of pTyr530 followed by conformational change that causes Src auto-phosphorylation at Tyr419 and its activation. HNE increased Src activation in both dose- and time-dependent manner, while it also increased Src phosphorylation at Tyr530 (pTyr530 Src), suggesting that HNE activated Src via a non-canonical mechanism. Protein tyrosine phosphatase 1B inhibitor (539741), at concentrations that increased basal pTyr530 Src, also increased basal Src activity and significantly reduced HNE-mediated Src activation. The EGFR inhibitor, AG1478, and EGFR silencing, abrogated HNE-mediated EGFR activation and inhibited basal and HNE-induced Src activity. In addition, AG1478 also eliminated the increase of basal Src activation by a PTP1B inhibitor. Taken together these data suggest that HNE can activate Src partly through a non-canonical pathway involving activation of EGFR and inhibition of PTP1B. PMID:26453921

  14. Lead acetate induces EGFR activation upstream of SFK and PKCα linkage to the Ras/Raf-1/ERK signaling

    International Nuclear Information System (INIS)

    Wang, C.-Y.; Wang, Y.-T.; Tzeng, D.-W.; Yang, J.-L.

    2009-01-01

    Lead acetate (Pb), a probable human carcinogen, can activate protein kinase C (PKC) upstream of extracellular signal-regulated kinase 1 and 2 (ERK1/2). Yet, it remains unclear whether Pb activation of PKC → ERK1/2 involves receptor/non-receptor tyrosine kinases and the Ras signaling transducer. Here we demonstrate a novel mechanism elicited by Pb for transmitting ERK1/2 signaling in CL3 human non-small-cell lung adenocarcinoma cells. Pb induction of higher steady-state levels of Ras-GTP was essential for increasing phospho-Raf-1 S338 and phospho-ERK1/2. Pre-treatment of the cells with a conventional PKC inhibitor Goe6976 or depleting PKCα using specific small interfering RNA blocked Pb induction of Ras-GTP. Pb also activated cellular tyrosine kinases. Specific pharmacological inhibitors, PD153035 for epidermal growth factor receptor (EGFR) and SU6656 for Src family tyrosine kinases (SFK), but not AG1296 for platelet-derived growth factor receptor, could suppress the Pb-induced tyrosine kinases, PKCα, Ras-GTP, phospho-Raf-1 S338 and phospho-ERK1/2. Furthermore, phosphorylation of tyrosines on the EGFR multiple autophosphorylation sites and the conserved SFK autophosphorylation site occurred during exposure of cells to Pb for 1-5 min and 5-30 min, respectively. Intriguingly, Pb activation of EGFR required the intrinsic kinase activity but not dimerization of the receptor. Inhibition of SFK or PKCα activities did not affect EGFR phosphorylation, while knockdown of EGFR blocked SFK phosphorylation and PKCα activation following Pb. Together, these results indicate that immediate activation of EGFR in response to Pb is obligatory for activation of SFK and PKCα and subsequent the Ras-Raf-1-MKK1/2-ERK1/2 signaling cascade

  15. Genomic activation of the EGFR and HER2-neu genes in a significant proportion of invasive epithelial ovarian cancers

    Directory of Open Access Journals (Sweden)

    Ghislain Vanessa

    2008-01-01

    Full Text Available Abstract Background The status of the EGFR and HER2-neu genes has not been fully defined in ovarian cancer. An integrated analysis of both genes could help define the proportion of patients that would potentially benefit from targeted therapies. Methods We determined the tumour mutation status of the entire tyrosine kinase (TK domain of the EGFR and HER2-neu genes in a cohort of 52 patients with invasive epithelial ovarian cancer as well as the gene copy number and protein expression of both genes in 31 of these patients by DGGE and direct sequecing, immunohistochemistry and Fluorescent in Situ Hybridisation (FISH. Results The EGFR was expressed in 59% of the cases, with a 2+/3+ staining intensity in 38%. HER2-neu expression was found in 35%, with a 2/3+ staining in 18%. No mutations were found in exons 18–24 of the TK domains of EGFR and HER2-neu. High polysomy of the EGFR gene was observed in 13% of the invasive epthelial cancers and amplification of the HER2-neu gene was found in 10% and correlated with a high expression level by immunohistochemistry. Mutations within the tyrosine kinase domain were not found in the entire TK domain of both genes, but have been found in very rare cases by others. Conclusion Genomic alteration of the HER2-neu and EGFR genes is frequent (25% in ovarian cancer. EGFR/HER2-neu targeted therapies should be investigated prospectively and specifically in that subset of patients.

  16. Urokinase-type plasminogen activator receptor (uPAR), tissue factor (TF) and epidermal growth factor receptor (EGFR)

    DEFF Research Database (Denmark)

    Christensen, Anders; Kiss, Katalin; Lelkaitis, Giedrius

    2017-01-01

    Background: Tumor-specific biomarkers are a prerequisite for the development of targeted imaging and therapy in oral squamous cell carcinoma (OSCC). urokinase-type Plasminogen Activator Receptor (uPAR), Tissue Factor (TF) and Epidermal Growth Factor Receptor (EGFR) are three biomarkers that exhib...... with a reduced survival. uPAR seems to be a prognostic biomarker in oral cancer....

  17. Activity of EGFR-tyrosine kinase and ALK inhibitors for EML4–ALK-rearranged non–small–cell lung cancer harbored coexisting EGFR mutation

    International Nuclear Information System (INIS)

    Miyanaga, Akihiko; Kawamoto, Masashi; Tsuchiya, Shinichi; Hagiwara, Koichi; Soda, Manabu; Takeuchi, Kengo; Yamamoto, Nobuyuki; Mano, Hiroyuki; Ishikawa, Yuichi; Gemma, Akihiko; Shimizu, Kumi; Noro, Rintaro; Seike, Masahiro; Kitamura, Kazuhiro; Kosaihira, Seiji; Minegishi, Yuji; Shukuya, Takehito; Yoshimura, Akinobu

    2013-01-01

    The EML4–ALK (echinoderm microtubule-associated protein-like 4 gene and the anaplastic lymphoma kinase gene) fusion oncogene represents a novel molecular target in a small subset of non–small–cell lung cancers (NSCLCs). The EML4–ALK fusion gene occurs generally in NSCLC without mutations in epidermal growth factor receptor (EGFR) and KRAS. We report that a case of EML4–ALK-positive NSCLC with EGFR mutation had a response of stable disease to both an EGFR tyrosine kinase inhibitor (EGFR-TKI) and ALK inhibitor. We described the first clinical report of a patient with EML4–ALK-positive NSCLC with EGFR mutation that had a response of stable disease to both single-agent EGFR-TKI and ALK inhibitor. EML4–ALK translocation may be associated with resistance to EGFR-TKI, and EGFR signaling may contribute to resistance to ALK inhibitor in EML4–ALK-positive NSCLC

  18. Hierarchical modeling of activation mechanisms in the ABL and EGFR kinase domains: thermodynamic and mechanistic catalysts of kinase activation by cancer mutations.

    Directory of Open Access Journals (Sweden)

    Anshuman Dixit

    2009-08-01

    Full Text Available Structural and functional studies of the ABL and EGFR kinase domains have recently suggested a common mechanism of activation by cancer-causing mutations. However, dynamics and mechanistic aspects of kinase activation by cancer mutations that stimulate conformational transitions and thermodynamic stabilization of the constitutively active kinase form remain elusive. We present a large-scale computational investigation of activation mechanisms in the ABL and EGFR kinase domains by a panel of clinically important cancer mutants ABL-T315I, ABL-L387M, EGFR-T790M, and EGFR-L858R. We have also simulated the activating effect of the gatekeeper mutation on conformational dynamics and allosteric interactions in functional states of the ABL-SH2-SH3 regulatory complexes. A comprehensive analysis was conducted using a hierarchy of computational approaches that included homology modeling, molecular dynamics simulations, protein stability analysis, targeted molecular dynamics, and molecular docking. Collectively, the results of this study have revealed thermodynamic and mechanistic catalysts of kinase activation by major cancer-causing mutations in the ABL and EGFR kinase domains. By using multiple crystallographic states of ABL and EGFR, computer simulations have allowed one to map dynamics of conformational fluctuations and transitions in the normal (wild-type and oncogenic kinase forms. A proposed multi-stage mechanistic model of activation involves a series of cooperative transitions between different conformational states, including assembly of the hydrophobic spine, the formation of the Src-like intermediate structure, and a cooperative breakage and formation of characteristic salt bridges, which signify transition to the active kinase form. We suggest that molecular mechanisms of activation by cancer mutations could mimic the activation process of the normal kinase, yet exploiting conserved structural catalysts to accelerate a conformational transition

  19. Sphingosine 1-Phosphate Activation of EGFR As a Novel Target for Meningitic Escherichia coli Penetration of the Blood-Brain Barrier

    Science.gov (United States)

    Wang, Xiangru; Maruvada, Ravi; Morris, Andrew J.; Liu, Jun O.; Baek, Dong Jae; Kim, Kwang Sik

    2016-01-01

    Central nervous system (CNS) infection continues to be an important cause of mortality and morbidity, necessitating new approaches for investigating its pathogenesis, prevention and therapy. Escherichia coli is the most common Gram-negative bacillary organism causing meningitis, which develops following penetration of the blood–brain barrier (BBB). By chemical library screening, we identified epidermal growth factor receptor (EGFR) as a contributor to E. coli invasion of the BBB in vitro. Here, we obtained the direct evidence that CNS-infecting E. coli exploited sphingosine 1-phosphate (S1P) for EGFR activation in penetration of the BBB in vitro and in vivo. We found that S1P was upstream of EGFR and participated in EGFR activation through S1P receptor as well as through S1P-mediated up-regulation of EGFR-related ligand HB-EGF, and blockade of S1P function through targeting sphingosine kinase and S1P receptor inhibited EGFR activation, and also E. coli invasion of the BBB. We further found that both S1P and EGFR activations occurred in response to the same E. coli proteins (OmpA, FimH, NlpI), and that S1P and EGFR promoted E. coli invasion of the BBB by activating the downstream c-Src. These findings indicate that S1P and EGFR represent the novel host targets for meningitic E. coli penetration of the BBB, and counteracting such targets provide a novel approach for controlling E. coli meningitis in the era of increasing resistance to conventional antibiotics. PMID:27711202

  20. Anti-tumor activity of high-dose EGFR tyrosine kinase inhibitor and sequential docetaxel in wild type EGFR non-small cell lung cancer cell nude mouse xenografts

    Science.gov (United States)

    Tang, Ning; Zhang, Qianqian; Fang, Shu; Han, Xiao; Wang, Zhehai

    2017-01-01

    Treatment of non-small-cell lung cancer (NSCLC) with wild-type epidermal growth factor receptor (EGFR) is still a challenge. This study explored antitumor activity of high-dose icotinib (an EGFR tyrosine kinase inhibitor) plus sequential docetaxel against wild-type EGFR NSCLC cells-generated nude mouse xenografts. Nude mice were subcutaneously injected with wild-type EGFR NSCLC A549 cells and divided into different groups for 3-week treatment. Tumor xenograft volumes were monitored and recorded, and at the end of experiments, tumor xenografts were removed for Western blot and immunohistochemical analyses. Compared to control groups (negative control, regular-dose icotinib [IcoR], high-dose icotinib [IcoH], and docetaxel [DTX]) and regular icotinib dose (60 mg/kg) with docetaxel, treatment of mice with a high-dose (1200 mg/kg) of icotinib plus sequential docetaxel for 3 weeks (IcoH-DTX) had an additive effect on suppression of tumor xenograft size and volume (P Icotinib-containing treatments markedly reduced phosphorylation of EGFR, mitogen activated protein kinase (MAPK), and protein kinase B (Akt), but only the high-dose icotinib-containing treatments showed an additive effect on CD34 inhibition (P icotinib plus docetaxel had a similar effect on mouse weight loss (a common way to measure adverse reactions in mice), compared to the other treatment combinations. The study indicate that the high dose of icotinib plus sequential docetaxel (IcoH-DTX) have an additive effect on suppressing the growth of wild-type EGFR NSCLC cell nude mouse xenografts, possibly through microvessel density reduction. Future clinical trials are needed to confirm the findings of this study. PMID:27852073

  1. Can EGFR mutation status be reliably determined in pre-operative needle biopsies from adenocarcinomas of the lung?

    DEFF Research Database (Denmark)

    Lindahl, Kim Hein; Sørensen, Flemming Brandt; Jonstrup, Søren Peter

    2015-01-01

    The identification of EGFR mutations in non-small-cell lung cancer is important for selecting patients, who may benefit from treatment with EGFR tyrosine kinase inhibitors. The analysis is usually performed on cytological aspirates and/or histological needle biopsies, representing a small fraction....... Moreover, several inconclusive results in the diagnostic biopsies reveal that attention must be paid on the suitability of pre-operative biopsies for EGFR mutation analysis....

  2. Droplet digital PCR-based EGFR mutation detection with an internal quality control index to determine the quality of DNA.

    Science.gov (United States)

    Kim, Sung-Su; Choi, Hyun-Jeung; Kim, Jin Ju; Kim, M Sun; Lee, In-Seon; Byun, Bohyun; Jia, Lina; Oh, Myung Ryurl; Moon, Youngho; Park, Sarah; Choi, Joon-Seok; Chae, Seoung Wan; Nam, Byung-Ho; Kim, Jin-Soo; Kim, Jihun; Min, Byung Soh; Lee, Jae Seok; Won, Jae-Kyung; Cho, Soo Youn; Choi, Yoon-La; Shin, Young Kee

    2018-01-11

    In clinical translational research and molecular in vitro diagnostics, a major challenge in the detection of genetic mutations is overcoming artefactual results caused by the low-quality of formalin-fixed paraffin-embedded tissue (FFPET)-derived DNA (FFPET-DNA). Here, we propose the use of an 'internal quality control (iQC) index' as a criterion for judging the minimum quality of DNA for PCR-based analyses. In a pre-clinical study comparing the results from droplet digital PCR-based EGFR mutation test (ddEGFR test) and qPCR-based EGFR mutation test (cobas EGFR test), iQC index ≥ 0.5 (iQC copies ≥ 500, using 3.3 ng of FFPET-DNA [1,000 genome equivalents]) was established, indicating that more than half of the input DNA was amplifiable. Using this criterion, we conducted a retrospective comparative clinical study of the ddEGFR and cobas EGFR tests for the detection of EGFR mutations in non-small cell lung cancer (NSCLC) FFPET-DNA samples. Compared with the cobas EGFR test, the ddEGFR test exhibited superior analytical performance and equivalent or higher clinical performance. Furthermore, iQC index is a reliable indicator of the quality of FFPET-DNA and could be used to prevent incorrect diagnoses arising from low-quality samples.

  3. Gemcitabine enhances cell invasion via activating HAb18G/CD147-EGFR-pSTAT3 signaling.

    Science.gov (United States)

    Xu, Bao-Qing; Fu, Zhi-Guang; Meng, Yao; Wu, Xiao-Qing; Wu, Bo; Xu, Liang; Jiang, Jian-Li; Li, Ling; Chen, Zhi-Nan

    2016-09-20

    Pancreatic cancer, one of the most lethal cancers, has very poor 5-year survival partly due to gemcitabine resistance. Recently, it was reported that chemotherapeutic agents may act as stressors to induce adaptive responses and to promote chemoresistance in cancer cells. During long-term drug treatment, the minority of cancer cells survive and acquire an epithelial-mesenchymal transition phenotype with increased chemo-resistance and metastasis. However, the short-term response of most cancer cells remains unclear. This study aimed to investigate the short-term response of pancreatic cancer cells to gemcitabine stress and to explore the corresponding mechanism. Our results showed that gemcitabine treatment for 24 hours enhanced pancreatic cancer cell invasion. In gemcitabine-treated cells, HAb18G/CD147 was up-regulated; and HAb18G/CD147 down-regulation or inhibition attenuated gemcitabine-enhanced invasion. Mechanistically, HAb18G/CD147 promoted gemcitabine-enhanced invasion by activating the EGFR (epidermal growth factor receptor)-STAT3 (signal transducer and activator of transcription 3) signaling pathway. Inhibition of EGFR-STAT3 signaling counteracted gemcitabine-enhanced invasion, and which relied on HAb18G/CD147 levels. In pancreatic cancer tissues, EGFR was highly expressed and positively correlated with HAb18G/CD147. These data indicate that pancreatic cancer cells enhance cell invasion via activating HAb18G/CD147-EGFR-pSTAT3 signaling. Our findings suggest that inhibiting HAb18G/CD147 is a potential strategy for overcoming drug stress-associated resistance in pancreatic cancer.

  4. Production of a germline-humanized cetuximab scFv and evaluation of its activity in recognizing EGFR- overexpressing cancer cells.

    Science.gov (United States)

    Banisadr, Arsham; Safdari, Yaghoub; Kianmehr, Anvarsadat; Pourafshar, Mahdieh

    2018-04-03

    The aim of this study was to produce a humanized single chain antibody (scFv) as a potential improved product design to target EGFR (Epidermal Growth Factor Receptor) overexpressing cancer cells. To this end, CDR loops of cetuximab (an FDA-approved anti-EGFR antibody) were grafted on framework regions derived from type 3 (VH3 and VL3 kappa) human germline sequences to obtain recombinant VH and VL domainslinked together with a flexible linker [(Gly 4 Ser) 3 ] to form a scFv. Codon optimized synthetic gene encoding the scFv (with NH2-VH-linker-VL-COOH orientation) was expressed in E. coli Origami™ 2(DE3) cells and the resultant scFv purified by using Ni-NTA affinity chromatography. The scFv, called cet.Hum scFv, was evaluated in ELISA and immunoblot to determine whether it can recognize EGFR. The scFv was able to recognize EGFR over-expressing cancer cells (A-431) but failed to detect cancer cells with low levels of EGFR (MCF-7 cells). Although the affinity of the scFv forA-431 cells was 9 fold lower than that of cetuximab, it was strong enough to recognize these cells. Considering its ability to bind EGFR molecules, the scFv may exhibit a potential application for the detection of EGFR-overexpressing cancer cells.

  5. The APPLE Trial: Feasibility and Activity of AZD9291 (Osimertinib) Treatment on Positive PLasma T790M in EGFR-mutant NSCLC Patients. EORTC 1613.

    Science.gov (United States)

    Remon, Jordi; Menis, Jessica; Hasan, Baktiar; Peric, Aleksandra; De Maio, Eleonora; Novello, Silvia; Reck, Martin; Berghmans, Thierry; Wasag, Bartosz; Besse, Benjamin; Dziadziuszko, Rafal

    2017-09-01

    The AZD9291 (Osimertinib) Treatment on Positive PLasma T790M in EGFR-mutant NSCLC Patients (APPLE) trial is a randomized, open-label, multicenter, 3-arm, phase II study in advanced, epidermal growth factor receptor (EGFR)-mutant and EGFR tyrosine kinase inhibitor (TKI)-naive non-small-cell lung cancer (NSCLC) patients, to evaluate the best strategy for sequencing gefitinib and osimertinib treatment. Advanced EGFR-mutant NSCLC patients, with World Health Organization performance status 0-2 who are EGFR TKI treatment-naive and eligible to receive first-line treatment with EGFR TKI will be randomized to: In all arms, a plasmatic ctDNA T790M test will be performed by a central laboratory at the Medical University of Gdansk (Poland) but will be applied as a predictive marker for making treatment decisions only in arm B. The primary objective is to evaluate the best strategy for sequencing of treatment with gefitinib and osimertinib in advanced NSCLC patients with common EGFR mutations, and to understand the value of liquid biopsy for the decision-making process. The progression-free survival rate at 18 months is the primary end point of the trial. The activity of osimertinib versus gefitinib to prevent brain metastases will be evaluated. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  6. NF-κB-Activating Complex Engaged in Response to EGFR Oncogene Inhibition Drives Tumor Cell Survival and Residual Disease in Lung Cancer

    Directory of Open Access Journals (Sweden)

    Collin M. Blakely

    2015-04-01

    Full Text Available Although oncogene-targeted therapy often elicits profound initial tumor responses in patients, responses are generally incomplete because some tumor cells survive initial therapy as residual disease that enables eventual acquired resistance. The mechanisms underlying tumor cell adaptation and survival during initial therapy are incompletely understood. Here, through the study of EGFR mutant lung adenocarcinoma, we show that NF-κB signaling is rapidly engaged upon initial EGFR inhibitor treatment to promote tumor cell survival and residual disease. EGFR oncogene inhibition induced an EGFR-TRAF2-RIP1-IKK complex that stimulated an NF-κB-mediated transcriptional survival program. The direct NF-κB inhibitor PBS-1086 suppressed this adaptive survival program and increased the magnitude and duration of initial EGFR inhibitor response in multiple NSCLC models, including a patient-derived xenograft. These findings unveil NF-κB activation as a critical adaptive survival mechanism engaged by EGFR oncogene inhibition and provide rationale for EGFR and NF-κB co-inhibition to eliminate residual disease and enhance patient responses.

  7. 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.

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

    International Nuclear Information System (INIS)

    Bian, Yong; Yu, Yun; Wang, Shanshan; Li, Lin

    2015-01-01

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Nicole M.; Ceresa, Brian P., E-mail: brian.ceresa@louisville.edu

    2016-08-15

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

  10. mTOR Inhibition Induces EGFR Feedback Activation in Association with Its Resistance to Human Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Feng Wei

    2015-02-01

    Full Text Available The mammalian target of rapamycin (mTOR is dysregulated in diverse cancers and contributes to tumor progression and drug resistance. The first generation of mTOR inhibitors have failed to show clinical efficiency in treating pancreatic cancers due in part to the feedback relief of the insulin-like growth factor-1 receptor (IGF-1R-AKT signaling pathway. The second generation of mTOR inhibitors, such as AZD8055, could inhibit AKT activation upon mTOR complex 2 (mTORC2 inhibition. However, whether this generation of mTOR inhibitors can obtain satisfactory activities in pancreatic cancer therapy remains unclear. In this study, we found AZD8055 did not show great improvement compared with everolimus, AZD8055 induced a temporal inhibition of AKT kinase activities and AKT was then rephosphorylated. Additionally, we found that AZD8055-induced transient AKT inhibition increased the expression and activation of epidermal growth factor receptor (EGFR by releasing its transcriptional factors Fork-head box O 1/3a (FoxO1/3a, which might contribute to cell resistance to AZD8055. The in vitro and in vivo experiments further indicated the combination of AZD8055 and erlotinib synergistically inhibited the mTORC1/C2 signaling pathway, EGFR/AKT feedback activation, and cell growth, as well as suppressed the progression of pancreatic cancer in a xenograft model. This study provides a rationale and strategy for overcoming AZD8055 resistance by a combined treatment with the EGFR inhibitor erlotinib in pancreatic cancer therapy.

  11. TCDD promoted EMT of hFPECs via AhR, which involved the activation of EGFR/ERK signaling

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Zhan [School of Public Health, Xinxiang Medical University, 453003 (China); The Fifth Affiliated Hospital, Zhengzhou University, 450052 (China); Bu, Yongjun [School of Public Health, Xinxiang Medical University, 453003 (China); Liu, Xiaozhuan [Medical College, Henan University of Science & Technology, 471023 (China); Wang, Xugang; Zhang, Guofu; Wang, Erhui; Ding, Shibin; Liu, Yongfeng; Shi, Ruling [School of Public Health, Xinxiang Medical University, 453003 (China); Li, Qiaoyun; Fu, Jianhong [The Fifth Affiliated Hospital, Zhengzhou University, 450052 (China); Yu, Zengli, E-mail: zly@zzu.edu.cn [School of Public Health, Xinxiang Medical University, 453003 (China); School of Public Health, Zhengzhou University, 450001 (China)

    2016-05-01

    One critical step of second palatal fusion is the newly formed medial epithelia seam (MES) disintegration, which involves apoptosis, epithelial to mesenchymal transition (EMT), and cell migration. Although the environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) produces cleft palate at high rates, little is known about the effects of TCDD exposure on the fate of palatal epithelial cells. By using primary epithelial cells isolated from human fetal palatal shelves (hFPECs), we show that TCDD increased cell proliferation and EMT, as demonstrated by increased the epithelial markers (E-cadherin and cytokeratin14) and enhanced the mesenchymal markers (vimentin and fibronectin), but had no effect on cell migration and apoptosis. TCDD exposure led to a dose-dependent increase in Slug protein expression. Coimmunoprecipitation revealed that TCDD promoted AhR to form a protein complex with Slug. ChIP assay confirmed that TCDD exposure recruited AhR to the xenobiotic responsive element of Slug promoter. Knockdown of AhR by siRNA remarkably weakened TCDD-induced binding of AhR to the XRE promoter of slug, thereby suppressed TCDD-induced vimentin. Further experiment showed that TCDD stimulated EGFR phosphorylation did not influence the TGFβ3/Smad signaling; whereas TCDD increased phosphorylation of ERK1/2 and p38 with no effect on activation of JNK. By using varieties of inhibitors, we confirmed that TCDD promoted proliferation and EMT of hFPECs via activation of EGFR/ERK pathway. These data make a novel contribution to the molecular mechanism of cleft palate by TCDD. - Highlights: • TCDD exposure promoted cell proliferation and EMT of hFPECs; • AhR signaling was activated and required for TCDD-induced EMT; • TCDD-mediated EMT of hFPECs involved the activation of EGFR/ERK signaling; • TCDD exposure had no effect on TGFβ3/Smad pathway.

  12. TCDD promoted EMT of hFPECs via AhR, which involved the activation of EGFR/ERK signaling

    International Nuclear Information System (INIS)

    Gao, Zhan; Bu, Yongjun; Liu, Xiaozhuan; Wang, Xugang; Zhang, Guofu; Wang, Erhui; Ding, Shibin; Liu, Yongfeng; Shi, Ruling; Li, Qiaoyun; Fu, Jianhong; Yu, Zengli

    2016-01-01

    One critical step of second palatal fusion is the newly formed medial epithelia seam (MES) disintegration, which involves apoptosis, epithelial to mesenchymal transition (EMT), and cell migration. Although the environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) produces cleft palate at high rates, little is known about the effects of TCDD exposure on the fate of palatal epithelial cells. By using primary epithelial cells isolated from human fetal palatal shelves (hFPECs), we show that TCDD increased cell proliferation and EMT, as demonstrated by increased the epithelial markers (E-cadherin and cytokeratin14) and enhanced the mesenchymal markers (vimentin and fibronectin), but had no effect on cell migration and apoptosis. TCDD exposure led to a dose-dependent increase in Slug protein expression. Coimmunoprecipitation revealed that TCDD promoted AhR to form a protein complex with Slug. ChIP assay confirmed that TCDD exposure recruited AhR to the xenobiotic responsive element of Slug promoter. Knockdown of AhR by siRNA remarkably weakened TCDD-induced binding of AhR to the XRE promoter of slug, thereby suppressed TCDD-induced vimentin. Further experiment showed that TCDD stimulated EGFR phosphorylation did not influence the TGFβ3/Smad signaling; whereas TCDD increased phosphorylation of ERK1/2 and p38 with no effect on activation of JNK. By using varieties of inhibitors, we confirmed that TCDD promoted proliferation and EMT of hFPECs via activation of EGFR/ERK pathway. These data make a novel contribution to the molecular mechanism of cleft palate by TCDD. - Highlights: • TCDD exposure promoted cell proliferation and EMT of hFPECs; • AhR signaling was activated and required for TCDD-induced EMT; • TCDD-mediated EMT of hFPECs involved the activation of EGFR/ERK signaling; • TCDD exposure had no effect on TGFβ3/Smad pathway.

  13. Preselection of EGFR mutations in non-small-cell lung cancer patients by immunohistochemistry: comparison with DNA-sequencing, EGFR wild-type expression, gene copy number gain and clinicopathological data.

    Science.gov (United States)

    Gaber, Rania; Watermann, Iris; Kugler, Christian; Vollmer, Ekkehard; Perner, Sven; Reck, Martin; Goldmann, Torsten

    2017-01-01

    Targeting epidermal growth factor receptor (EGFR) in patients with non-small-cell lung cancer (NSCLC) having EGFR mutations is associated with an improved overall survival. The aim of this study is to verify, if EGFR mutations detected by immunohistochemistry (IHC) is a convincing way to preselect patients for DNA-sequencing and to figure out, the statistical association between EGFR mutation, wild-type EGFR overexpression, gene copy number gain, which are the main factors inducing EGFR tumorigenic activity and the clinicopathological data. Two hundred sixteen tumor tissue samples of primarily chemotherapeutic naïve NSCLC patients were analyzed for EGFR mutations E746-A750del and L858R and correlated with DNA-sequencing. Two hundred six of which were assessed by IHC, using 6B6 and 43B2 specific antibodies followed by DNA-sequencing of positive cases and 10 already genotyped tumor tissues were also included to investigate debugging accuracy of IHC. In addition, EGFR wild-type overexpression was IHC evaluated and EGFR gene copy number determination was performed by fluorescence in situ hybridization (FISH). Forty-one÷206 (19.9%) cases were positive for mutated EGFR by IHC. Eight of them had EGFR mutations of exons 18-21 by DNA-sequencing. Hit rate of 10 already genotyped NSCLC mutated cases was 90% by IHC. Positive association was found between EGFR mutations determined by IHC and both EGFR overexpression and increased gene copy number (p=0.002 and p<0.001, respectively). Additionally, positive association was detected between EGFR mutations, high tumor grade and clinical stage (p<0.001). IHC staining with mutation specific antibodies was demonstrated as a possible useful screening test to preselect patients for DNA-sequencing.

  14. Study on the proliferation of human gastric cancer cell AGS by activation of EGFR in H2O2.

    Science.gov (United States)

    Wang, Q; Shen, W; Tao, G-Q; Sun, J; Shi, L-P

    2017-03-01

    This study is to investigate the effect of low concentration hydrogen peroxide (H2O2) on the proliferation of gastric cancer AGS cell line in vitro and the mechanism. AGS cells were treated with different low concentrations of H2O2 (1, 0.1, 0.01, and 0.001 μm) for 48 hours. The effect of H2O2 concentration gradient on the activity of AGS cell activities was detected by methyl thiazolyl tetrazolium (MTT) method. The expression of the epidermal growth factor receptor (EGFR) and its downstream signaling pathway extracellular signal-regulated kinase (ERK) protein in H2O2 was detected by Western blot method; moreover, the effect of H2O2 on intracellular reactive oxygen species (ROS) in AGS cells was observed under the fluorescence microscope and quantitative analysis by flow cytometry. The effect of H2O2 on the level of c-myc mRNA in AGS cells was also detected by reverse transcription polymerase chain reaction (RT-PCR). MTT detection results showed that 1 μm and 0.1 μm H2O2 at 48h can effectively promote the proliferation of AGS cells (pH2O2 treatment of AGS cells, the EGFR protein levels and ERK protein phosphorylation levels increased significantly (pH2O2 increased the intracellular reactive oxygen species (ROS). RT-PCR results showed the levels of c-myc mRNA in AGS cells treated with a low concentration of H2O2 were significantly increased (pH2O2 can significantly promote the proliferation of AGS cells by activating EGFR/ERK signaling pathway.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-08-15

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

  16. Activation of ErbB3, EGFR and Erk is essential for growth of human breast cancer cell lines with acquired resistance to fulvestrant

    DEFF Research Database (Denmark)

    Frogne, Thomas; Benjaminsen, Rikke; Sonne-Hansen, Katrine

    2008-01-01

    cell lines concomitant with inhibition of Erk and unaltered Akt activation. In concert, inhibition of Erk with U0126 preferentially reduced growth of resistant cell lines. Treatment with ErbB3 neutralizing antibodies inhibited ErbB3 activation and resulted in a modest but statistically significant...... activation was observed only in the parental MCF-7 cells. The downstream kinases pAkt and pErk were increased in five of seven and in all seven resistant cell lines, respectively. Treatment with the EGFR inhibitor gefitinib preferentially inhibited growth and reduced the S phase fraction in the resistant...... growth inhibition of two resistant cell lines. These data indicate that ligand activated ErbB3 and EGFR, and Erk signaling play important roles in fulvestrant resistant cell growth. Furthermore, the decreased level of ErbB4 in resistant cells may facilitate heterodimerization of ErbB3 with EGFR and ErbB2...

  17. Periodic mechanical stress activates EGFR-dependent Rac1 mitogenic signals in rat nucleus pulpous cells via ERK1/2

    International Nuclear Information System (INIS)

    Gao, Gongming; Shen, Nan; Jiang, Xuefeng; Sun, Huiqing; Xu, Nanwei; Zhou, Dong; Nong, Luming; Ren, Kewei

    2016-01-01

    The mitogenic effects of periodic mechanical stress on nucleus pulpous cells have been studied extensively but the mechanisms whereby nucleus pulpous cells sense and respond to mechanical stimulation remain a matter of debate. We explored this question by performing cell culture experiments in our self-developed periodic stress field and perfusion culture system. Under periodic mechanical stress, rat nucleus pulpous cell proliferation was significantly increased (p < 0.05 for each) and was associated with increases in the phosphorylation and activation of EGFR, Rac1, and ERK1/2 (p < 0.05 for each). Pretreatment with the ERK1/2 selective inhibitor PD98059 reduced periodic mechanical stress-induced nucleus pulpous cell proliferation (p < 0.05 for each), while the activation levels of EGFR and Rac1 were not inhibited. Proliferation and phosphorylation of ERK1/2 were inhibited after pretreatment with the Rac1 inhibitor NSC23766 in nucleus pulpous cells in response to periodic mechanical stress (p < 0.05 for each), while the phosphorylation site of EGFR was not affected. Inhibition of EGFR activity with AG1478 abrogated nucleus pulpous cell proliferation (p < 0.05 for each) and attenuated Rac1 and ERK1/2 activation in nucleus pulpous cells subjected to periodic mechanical stress (p < 0.05 for each). These findings suggest that periodic mechanical stress promotes nucleus pulpous cell proliferation in part through the EGFR-Rac1-ERK1/2 signaling pathway, which links these three important signaling molecules into a mitogenic cascade. - Highlights: • The mechanism involved in nucleus pulpous cells to respond to mechanical stimuli. • Periodic mechanical stress can stimulate the phosphorylation of EGFR. • EGFR activates Rac1 and leads to rat nucleus pulpous cell proliferation. • EGFR and Rac1 activate ERK1/2 mitogenic signals in nucleus pulpous cells. • EGFR-Rac1-ERK1/2 is constitutes at least one critical signal transduction pathway.

  18. Periodic mechanical stress activates EGFR-dependent Rac1 mitogenic signals in rat nucleus pulpous cells via ERK1/2

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Gongming [Department of Orthopedics, The Affiliated Changzhou No. 2 Hospital of Nanjing Medical University, Changzhou 213003 (China); Shen, Nan [Department of Clinical Pharmacy, The Affiliated Jiangyin Hospital of Southeast University Medical School, Jiangyin 214400 (China); Jiang, Xuefeng; Sun, Huiqing [Department of Orthopedics, The Affiliated Jiangyin Hospital of Southeast University Medical School, Jiangyin 214400 (China); Xu, Nanwei; Zhou, Dong [Department of Orthopedics, The Affiliated Changzhou No. 2 Hospital of Nanjing Medical University, Changzhou 213003 (China); Nong, Luming, E-mail: lumingnong@hotmail.com [Department of Orthopedics, The Affiliated Changzhou No. 2 Hospital of Nanjing Medical University, Changzhou 213003 (China); Ren, Kewei, E-mail: keweiren@hotmail.com [Department of Orthopedics, The Affiliated Jiangyin Hospital of Southeast University Medical School, Jiangyin 214400 (China)

    2016-01-15

    The mitogenic effects of periodic mechanical stress on nucleus pulpous cells have been studied extensively but the mechanisms whereby nucleus pulpous cells sense and respond to mechanical stimulation remain a matter of debate. We explored this question by performing cell culture experiments in our self-developed periodic stress field and perfusion culture system. Under periodic mechanical stress, rat nucleus pulpous cell proliferation was significantly increased (p < 0.05 for each) and was associated with increases in the phosphorylation and activation of EGFR, Rac1, and ERK1/2 (p < 0.05 for each). Pretreatment with the ERK1/2 selective inhibitor PD98059 reduced periodic mechanical stress-induced nucleus pulpous cell proliferation (p < 0.05 for each), while the activation levels of EGFR and Rac1 were not inhibited. Proliferation and phosphorylation of ERK1/2 were inhibited after pretreatment with the Rac1 inhibitor NSC23766 in nucleus pulpous cells in response to periodic mechanical stress (p < 0.05 for each), while the phosphorylation site of EGFR was not affected. Inhibition of EGFR activity with AG1478 abrogated nucleus pulpous cell proliferation (p < 0.05 for each) and attenuated Rac1 and ERK1/2 activation in nucleus pulpous cells subjected to periodic mechanical stress (p < 0.05 for each). These findings suggest that periodic mechanical stress promotes nucleus pulpous cell proliferation in part through the EGFR-Rac1-ERK1/2 signaling pathway, which links these three important signaling molecules into a mitogenic cascade. - Highlights: • The mechanism involved in nucleus pulpous cells to respond to mechanical stimuli. • Periodic mechanical stress can stimulate the phosphorylation of EGFR. • EGFR activates Rac1 and leads to rat nucleus pulpous cell proliferation. • EGFR and Rac1 activate ERK1/2 mitogenic signals in nucleus pulpous cells. • EGFR-Rac1-ERK1/2 is constitutes at least one critical signal transduction pathway.

  19. Acquired resistance of EGFR-mutant lung adenocarcinomas to afatinib plus cetuximab is associated with activation of mTORC1

    Science.gov (United States)

    Pirazzoli, Valentina; Nebhan, Caroline; Song, Xiaoling; Wurtz, Anna; Walther, Zenta; Cai, Guoping; Zhao, Zhongming; Jia, Peilin; de Stanchina, Elisa; Shapiro, Erik M.; Gale, Molly; Yin, Ruonan; Horn, Leora; Carbone, David P.; Stephens, Philip J; Miller, Vincent; Gettinger, Scott; Pao, William; Politi, Katerina

    2014-01-01

    SUMMARY Patients with EGFR-mutant lung adenocarcinomas (LUADs) who initially respond to first-generation TKIs develop resistance to these drugs. A combination of the irreversible TKI afatinib and the EGFR antibody cetuximab can be used to overcome resistance to first-generation TKIs; however, resistance to this drug combination eventually emerges. We identified activation of the mTORC1 signaling pathway as a mechanism of resistance to dual inhibition of EGFR in mouse models. Addition of rapamycin reversed resistance in vivo. Analysis of afatinib+cetuximab-resistant biopsy specimens revealed the presence of genomic alterations in genes that modulate mTORC1 signaling including NF2 and TSC1. These findings pinpoint enhanced mTORC1 activation as a mechanism of resistance to afatinib+cetuximab and identify genomic mechanisms that lead to activation of this pathway, revealing a potential therapeutic strategy for treating patients with resistance to these drugs. PMID:24813888

  20. Functional cooperation between HIF-1α and c-Jun in mediating primary and acquired resistance to gefitinib in NSCLC cells with activating mutation of EGFR.

    Science.gov (United States)

    Meng, Shuyan; Wang, Guorui; Lu, Yang; Fan, Zhen

    2018-07-01

    Hypoxia-inducible factor 1 (HIF-1) and activator protein 1 (AP-1) are important transcription factors regulating expression of genes involved in cell survival. HIF-1α and c-Jun are key components of HIF-1 and AP-1, respectively, and are regulated by epidermal growth factor receptor (EGFR)-mediated cell signaling and tumor microenvironmental cues. The roles of HIF-1α and c-Jun in development of resistance to EGFR tyrosine kinase inhibitor (TKI) in non-small cell lung cancer (NSCLC) with activating mutation of EGFR have not been explored. In this study, we investigated the roles of HIF-1α and c-Jun in mediating primary and acquired resistance to gefitinib in NSCLC cells with activating mutation of EGFR. Changes in HIF-1α protein and in total and phosphorylated c-Jun levels in relation to changes in total and phosphorylated EGFR levels before and after gefitinib treatment were measured using Western blot analysis in NSCLC cells sensitive or resistant to gefitinib. The impact of overexpression of a constitutively expressed HIF-1α (HIF-1α/ΔODD) or a constitutively active c-Jun upstream regulator (SEK1 S220E/T224D mutant) on cell response to gefitinib was also examined. The effect of pharmacological inhibition of SEK1-JNK-c-Jun pathway on cell response to gefitinib was evaluated. Downregulation of HIF-1α and total and phosphorylated c-Jun levels correlated with cell inhibitory response to gefitinib better than decrease in phosphorylated EGFR did in NSCLC cells with intrinsic or acquired resistance to gefitinib. Overexpression of HIF-1α/ΔODD or SEK1 S220E/T224D mutant conferred resistance to gefitinib. There exists a positive feed-forward regulation loop between HIF-1 and c-Jun. The JNK inhibitor SP600125 sensitized gefitinib-resistant NSCLC cells to gefitinib. HIF-1α and c-Jun functionally cooperate in development of resistance to gefitinib in NSCLC cells. The translational value of inhibiting HIF-1α/c-Jun cooperation in overcoming resistance to EGFR TKI

  1. TGF-β and Hypoxia/Reoxygenation Promote Radioresistance of A549 Lung Cancer Cells through Activation of Nrf2 and EGFR

    Directory of Open Access Journals (Sweden)

    Sae-lo-oom Lee

    2016-01-01

    Full Text Available Although many studies have examined the roles of hypoxia and transforming growth factor- (TGF- β separately in the tumor microenvironment, the effects of simultaneous treatment with hypoxia/reoxygenation and TGF-β on tumor malignancy are unclear. Here, we investigated the effects of redox signaling and oncogenes on cell proliferation and radioresistance in A549 human lung cancer cells in the presence of TGF-β under hypoxia/reoxygenation conditions. Combined treatment with TGF-β and hypoxia activated epidermal growth factor receptor (EGFR and nuclear factor (erythroid-derived 2-like 2 (Nrf2, a redox-sensitive transcription factor. Interestingly, Nrf2 knockdown suppressed the effects of combined treatment on EGFR phosphorylation. In addition, blockade of EGFR signaling also suppressed induction of Nrf2 following combined treatment with hypoxia and TGF-β, indicating that the combined treatment induced positive crosstalk between Nrf2 and EGFR. TGF-β and hypoxia/reoxygenation increased the accumulation of reactive oxygen species (ROS, while treatment with N-acetyl-L-cysteine abolished the activation of Nrf2 and EGFR. Treatment with TGF-β under hypoxic conditions increased the proliferation of A549 cells compared with that after vehicle treatment. Moreover, cells treated with the combined treatment exhibited resistance to ionizing radiation (IR, and knockdown of Nrf2 increased IR-induced cell death under these conditions. Thus, taken together, our findings suggested that TGF-β and hypoxia/reoxygenation promoted tumor progression and radioresistance of A549 cells through ROS-mediated activation of Nrf2 and EGFR.

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

    International Nuclear Information System (INIS)

    Gu, Da-min; Lu, Pei-Hua; Zhang, Ke; Wang, Xiang; Sun, Min; Chen, Guo-Qian; Wang, Qiong

    2015-01-01

    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

  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. EGF-R is Expressed and AP-1 and NF-κ:B Are Activated in Stromal Myofibroblasts Surrounding Colon Adenocarcinomas Paralleling Expression of COX-2 and VEGF

    Directory of Open Access Journals (Sweden)

    Panagiotis A. Konstantinopoulos

    2007-01-01

    Full Text Available Background: COX-2 and VEGF are important triggers of colon cancer growth, metastasis and angiogenesis. Cox-2 promoter contains transcriptional regulatory elements for AP-1 and NF-κ:B transcription factors whilst vegf is a known AP-1 downstream target gene. We investigated whether stromal myofibroblasts surrounding colon adenocarcinomas express COX-2 and VEGF and whether activation of AP-1 and NF-κ:B, as well as expression of EGF-R parallel expression of COX-2 and VEGF in these cells. Methods: Immunohistochemical methodology was performed on archival sections from 40 patients with colon adenocarcinomas. We evaluated c-FOS, p-c-JUN (phosphorylated c-JUN, p-Iκ:B-α (phosphorylated Iκ:B-α, EGF-R, COX-2, NF-κ:B and VEGF expression in stromal myofibroblasts surrounding colon adenocarcinomas. Double immunostaining with a-smooth muscle actin and each antibody was done to verify the expression of these molecules in stromal myofibroblasts. Results: VEGF, p-Iκ:B-α, NF-κ:B, c-FOS, p-c-JUN, EGF-R and COX-2 were expressed in stromal myofibroblasts surrounding colon adenocarcinomas in the majority of cases. EGF-R, p-Iκ:B-α, NF-κ:B, c-FOS and p-c-JUN correlated positively with COX-2 and VEGF expression. Conclusion: Stromal myofibroblasts surrounding colon adenocarcinomas are an important source of VEGF and COX-2 production, while AP-1 and NF-κ:B transcription factors are activated and EGF-R is expressed in these cells and associated with COX-2 and VEGF production.

  5. Determination of HER2 and p53 Mutations by Sequence Analysis Method and EGFR/Chromosome 7 Gene Status by Fluorescence in Situ Hybridization for the Predilection of Targeted Therapy Modalities in Immunohistochemically Triple Negative Breast Carcinomas in Turkish Population.

    Science.gov (United States)

    Pala, Emel Ebru; Bayol, Umit; Keskin, Elif Usturali; Ozguzer, Alp; Kucuk, Ulku; Ozer, Ozge; Koc, Altug

    2015-09-01

    Triple negative breast cancer (TNBC), an agressive subtype accounts nearly 15 % of all breast carcinomas. Conventional chemotherapy is the only treatment modality thus new, effective targeted therapy methods have been investigated. Epidermal growth factor receptor (EGFR) inhibitors give hope according to the recent studies results. Also therapeutic agents have been tried against aberrant p53 signal activity as TNBC show high p53 mutation rates. Our aim was to detect the incidence of mutations/amplifications identified in TNBC in our population. Here we used sequence analysis to detect HER2 (exon 18-23), p53 (exon 5-8) mutations; fluorescence in situ hybridization (FISH) method to analyse EGFR/chromosome 7 centromere gene status in 82 immunohistochemically TNBC. Basaloid phenotype was identified in 49 (59.8 %) patients. EGFR amplification was noted in 5 cases (6.1 %). All EGFR amplified cases showed EGFR overexpression by immunohistochemistry (IHC). p53 mutations were identified in 33 (40.2 %) cases. Almost 60 % of the basal like breast cancer cases showed p53 mutation. Only one case showed HER2 mutation (exon 20:g.36830_3). Our results showed that gene amplification is not the unique mechanism in EGFR overexpression. IHC might be used in the decision of anti-EGFR therapy in routine practice. p53 mutation rate was lower than the rates reported in the literature probably due to ethnic differences and low sensitivity of sanger sequences in general mutation screening. We also established the rarity of HER2 mutation in TNBC. In conclusion EGFR and p53 are the major targets in TNBC also for our population.

  6. Acquired Resistance of EGFR-Mutant Lung Adenocarcinomas to Afatinib plus Cetuximab Is Associated with Activation of mTORC1

    Directory of Open Access Journals (Sweden)

    Valentina Pirazzoli

    2014-05-01

    Full Text Available Patients with EGFR-mutant lung adenocarcinomas (LUADs who initially respond to first-generation tyrosine kinase inhibitors (TKIs develop resistance to these drugs. A combination of the irreversible TKI afatinib and the EGFR antibody cetuximab can be used to overcome resistance to first-generation TKIs; however, resistance to this drug combination eventually emerges. We identified activation of the mTORC1 signaling pathway as a mechanism of resistance to dual inhibition of EGFR in mouse models. The addition of rapamycin reversed resistance in vivo. Analysis of afatinib-plus-cetuximab-resistant biopsy specimens revealed the presence of genomic alterations in genes that modulate mTORC1 signaling, including NF2 and TSC1. These findings pinpoint enhanced mTORC1 activation as a mechanism of resistance to afatinib plus cetuximab and identify genomic mechanisms that lead to activation of this pathway, revealing a potential therapeutic strategy for treating patients with resistance to these drugs.

  7. Monocytes/macrophages support mammary tumor invasivity by co-secreting lineage-specific EGFR ligands and a STAT3 activator

    International Nuclear Information System (INIS)

    Vlaicu, Philip; Mertins, Philipp; Mayr, Thomas; Widschwendter, Peter; Ataseven, Beyhan; Högel, Bernhard; Eiermann, Wolfgang; Knyazev, Pjotr; Ullrich, Axel

    2013-01-01

    Tumor-associated macrophages (TAM) promote malignant progression, yet the repertoire of oncogenic factors secreted by TAM has not been clearly defined. We sought to analyze which EGFR- and STAT3-activating factors are secreted by monocytes/macrophages exposed to tumor cell-secreted factors. Following exposure of primary human monocytes and macrophages to supernatants of a variety of tumor cell lines, we have analyzed transcript and secreted protein levels of EGFR family ligands and of STAT3 activators. To validate our findings, we have analyzed TAM infiltration levels, systemic and local protein levels as well as clinical data of primary breast cancer patients. Primary human monocytes and macrophages respond to tumor cell-derived factors by secreting EGFR- and STAT3-activating ligands, thus inducing two important oncogenic pathways in carcinoma cells. Tumor cell-secreted factors trigger two stereotype secretory profiles in peripheral blood monocytes and differentiated macrophages: monocytes secrete epiregulin (EREG) and oncostatin-M (OSM), while macrophages secrete heparin-binding EGF-like growth factor (HB-EGF) and OSM. HB-EGF and OSM cooperatively induce tumor cell chemotaxis. HB-EGF and OSM are co-expressed by TAM in breast carcinoma patients, and plasma levels of both ligands correlate strongly. Elevated HB-EGF levels accompany TAM infiltration, tumor growth and dissemination in patients with invasive disease. Our work identifies systemic markers for TAM involvement in cancer progression, with the potential to be developed into molecular targets in cancer therapy

  8. EGFR is not a major driver for osteosarcoma cell growth in vitro but contributes to starvation and chemotherapy resistance.

    Science.gov (United States)

    Sevelda, Florian; Mayr, Lisa; Kubista, Bernd; Lötsch, Daniela; van Schoonhoven, Sushilla; Windhager, Reinhard; Pirker, Christine; Micksche, Michael; Berger, Walter

    2015-11-02

    Enhanced signalling via the epidermal growth factor receptor (EGFR) is a hallmark of multiple human carcinomas. However, in recent years data have accumulated that EGFR might also be hyperactivated in human sarcomas. Aim of this study was to investigate the influence of EGFR inhibition on cell viability and its interaction with chemotherapy response in osteosarcoma cell lines. We have investigated a panel of human osteosarcoma cell lines regarding EGFR expression and downstream signalling. To test its potential applicability as therapeutic target, inhibition of EGFR by gefitinib was combined with osteosarcoma chemotherapeutics and cell viability, migration, and cell death assays were performed. Osteosarcoma cells expressed distinctly differing levels of functional EGFR reaching in some cases high amounts. Functionality of EGFR in osteosarcoma cells was proven by EGF-mediated activation of both MAPK and PI3K/AKT pathway (determined by phosphorylation of ERK1/2, AKT, S6, and GSK3β). The EGFR-specific inhibitor gefitinib blocked EGF-mediated downstream signal activation. At standard in vitro culture conditions, clinically achievable gefitinib doses demonstrated only limited cytotoxic activity, however, significantly reduced long-term colony formation and cell migration. In contrast, under serum-starvation conditions active gefitinib doses were distinctly reduced while EGF promoted starvation survival. Importantly, gefitinib significantly supported the anti-osteosarcoma activities of doxorubicin and methotrexate regarding cell survival and migratory potential. Our data suggest that EGFR is not a major driver for osteosarcoma cell growth but contributes to starvation- and chemotherapy-induced stress survival. Consequently, combination approaches including EGFR inhibitors should be evaluated for treatment of high-grade osteosarcoma patients.

  9. Small tyrosine kinase inhibitors interrupt EGFR signaling by interacting with erbB3 and erbB4 in glioblastoma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Carrasco-Garcia, Estefania; Saceda, Miguel [Instituto de Biologia Molecular y Celular, Universidad Miguel Hernandez, 03202 Elche (Alicante) (Spain); Unidad de Investigacion, Hospital General Universitario de Elche, 03203 Elche (Alicante) (Spain); Grasso, Silvina; Rocamora-Reverte, Lourdes; Conde, Mariano; Gomez-Martinez, Angeles [Instituto de Biologia Molecular y Celular, Universidad Miguel Hernandez, 03202 Elche (Alicante) (Spain); Garcia-Morales, Pilar [Instituto de Biologia Molecular y Celular, Universidad Miguel Hernandez, 03202 Elche (Alicante) (Spain); Unidad de Investigacion, Hospital General Universitario de Elche, 03203 Elche (Alicante) (Spain); Ferragut, Jose A. [Instituto de Biologia Molecular y Celular, Universidad Miguel Hernandez, 03202 Elche (Alicante) (Spain); Martinez-Lacaci, Isabel, E-mail: imlacaci@umh.es [Instituto de Biologia Molecular y Celular, Universidad Miguel Hernandez, 03202 Elche (Alicante) (Spain); Unidad AECC de Investigacion Traslacional en Cancer, Hospital Universitario Virgen de la Arrixaca, 30120 Murcia (Spain)

    2011-06-10

    Signaling through the epidermal growth factor receptor (EGFR) is relevant in glioblastoma. We have determined the effects of the EGFR inhibitor AG1478 in glioblastoma cell lines and found that U87 and LN-229 cells were very sensitive to this drug, since their proliferation diminished and underwent a marked G{sub 1} arrest. T98 cells were a little more refractory to growth inhibition and A172 cells did not undergo a G{sub 1} arrest. This G{sub 1} arrest was associated with up-regulation of p27{sup kip1}, whose protein turnover was stabilized. EGFR autophosphorylation was blocked with AG1478 to the same extent in all the cell lines. Other small-molecule EGFR tyrosine kinase inhibitors employed in the clinic, such as gefitinib, erlotinib and lapatinib, were able to abrogate proliferation of glioblastoma cell lines, which underwent a G{sub 1} arrest. However, the EGFR monoclonal antibody, cetuximab had no effect on cell proliferation and consistently, had no effect on cell cycle either. Similarly, cetuximab did not inhibit proliferation of U87 {Delta}EGFR cells or primary glioblastoma cell cultures, whereas small-molecule EGFR inhibitors did. Activity of downstream signaling molecules of EGFR such as Akt and especially ERK1/2 was interrupted with EGFR tyrosine kinase inhibitors, whereas cetuximab treatment could not sustain this blockade over time. Small-molecule EGFR inhibitors were able to prevent phosphorylation of erbB3 and erbB4, whereas cetuximab only hindered EGFR phosphorylation, suggesting that EGFR tyrosine kinase inhibitors may mediate their anti-proliferative effects through other erbB family members. We can conclude that small-molecule EGFR inhibitors may be a therapeutic approach for the treatment of glioblastoma patients.

  10. Molecular Basis for Necitumumab Inhibition of EGFR Variants Associated with Acquired Cetuximab Resistance.

    Science.gov (United States)

    Bagchi, Atrish; Haidar, Jaafar N; Eastman, Scott W; Vieth, Michal; Topper, Michael; Iacolina, Michelle D; Walker, Jason M; Forest, Amelie; Shen, Yang; Novosiadly, Ruslan D; Ferguson, Kathryn M

    2018-02-01

    Acquired resistance to cetuximab, an antibody that targets the EGFR, impacts clinical benefit in head and neck, and colorectal cancers. One of the mechanisms of resistance to cetuximab is the acquisition of mutations that map to the cetuximab epitope on EGFR and prevent drug binding. We find that necitumumab, another FDA-approved EGFR antibody, can bind to EGFR that harbors the most common cetuximab-resistant substitution, S468R (or S492R, depending on the amino acid numbering system). We determined an X-ray crystal structure to 2.8 Å resolution of the necitumumab Fab bound to an S468R variant of EGFR domain III. The arginine is accommodated in a large, preexisting cavity in the necitumumab paratope. We predict that this paratope shape will be permissive to other epitope substitutions, and show that necitumumab binds to most cetuximab- and panitumumab-resistant EGFR variants. We find that a simple computational approach can predict with high success which EGFR epitope substitutions abrogate antibody binding. This computational method will be valuable to determine whether necitumumab will bind to EGFR as new epitope resistance variants are identified. This method could also be useful for rapid evaluation of the effect on binding of alterations in other antibody/antigen interfaces. Together, these data suggest that necitumumab may be active in patients who are resistant to cetuximab or panitumumab through EGFR epitope mutation. Furthermore, our analysis leads us to speculate that antibodies with large paratope cavities may be less susceptible to resistance due to mutations mapping to the antigen epitope. Mol Cancer Ther; 17(2); 521-31. ©2017 AACR . ©2017 American Association for Cancer Research.

  11. EGFR and Bcl-2 in gastric mucosa of children infected with Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Ewa Ryszczuk

    2016-03-01

    Full Text Available Aim: The aim of the study was to evaluate the expression of EGFR and Bcl-2 proteins as inhibitory markers of apoptosis in surface epithelial cells and gland cells of antral gastric mucosa in children infected with Helicobacter pylori according to the severity and activity of antral gastritis and to assess the correlation between the number of cells expressing EGFR and the number of cells expressing Bcl-2 in H. pylori infected children.Materials and methods: The study included 44 children: 68.2% with chronic gastritis and positive IgG against H. pylori, and 31.8% with functional disorders of the gastrointestinal tract and with normal IgG against H. pylori. The evaluation of EGFR expression in gastric mucosa was performed immunohistochemically using monoclonal mouse anti-EGFR antibody. The polyclonal antibody was used to determine the expression of anti-Bcl-2.Results: A significant increase in the number of cells expressing EGFR and Bcl-2 protein was found in the epithelial cells in severe as well as mild and moderate gastritis in the group of children infected with H. pylori. An increase in the number of cells expressing EGFR and Bcl-2 protein was also found in the epithelial cells in group I according to the activity of gastritis. There was a statistically significant positive correlation between the numbers of cells expressing EGFR and Bcl-2 in H. pylori infected children.Conclusion: Increased expression of EGFR and Bcl-2 proteins in the epithelial cells and a statistically significant positive correlation between the numbers of cells expressing EGFR and Bcl-2 in H. pylori infected children could suggest increased regeneration abilities of gastric mucosa.

  12. 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 intr...... aspects of therapeutic targeting of EGFR....

  13. Gene Expression of the EGF System-a Prognostic Model in Non-Small Cell Lung Cancer Patients Without Activating EGFR Mutations

    DEFF Research Database (Denmark)

    Sandfeld-Paulsen, Birgitte; Folkersen, Birgitte Holst; Rasmussen, Torben Riis

    2016-01-01

    OBJECTIVES: Contradicting results have been demonstrated for the expression of the epidermal growth factor receptor (EGFR) as a prognostic marker in non-small cell lung cancer (NSCLC). The complexity of the EGF system with four interacting receptors and more than a dozen activating ligands is a l.......17-6.47], P model that takes the complexity of the EGF system into account and shows that this model is a strong prognostic marker in NSCLC patients.......OBJECTIVES: Contradicting results have been demonstrated for the expression of the epidermal growth factor receptor (EGFR) as a prognostic marker in non-small cell lung cancer (NSCLC). The complexity of the EGF system with four interacting receptors and more than a dozen activating ligands...... is a likely explanation. The aim of this study is to demonstrate that the combined network of receptors and ligands from the EGF system is a prognostic marker. MATERIAL AND METHODS: Gene expression of the receptors EGFR, HER2, HER3, HER4, and the ligands AREG, HB-EGF, EPI, TGF-α, and EGF was measured...

  14. Integrated ligand-receptor bioinformatic and in vitro functional analysis identifies active TGFA/EGFR signaling loop in papillary thyroid carcinomas.

    Directory of Open Access Journals (Sweden)

    Debora Degl'Innocenti

    Full Text Available BACKGROUND: Papillary thyroid carcinoma (PTCs, the most frequent thyroid cancer, is usually not life threatening, but may recur or progress to aggressive forms resistant to conventional therapies. A more detailed understanding of the signaling pathways activated in PTCs may help to identify novel therapeutic approaches against these tumors. The aim of this study is to identify signaling pathways activated in PTCs. METHODOLOGY/PRINCIPAL FINDINGS: We examined coordinated gene expression patterns of ligand/receptor (L/R pairs using the L/R database DRLP-rev1 and five publicly available thyroid cancer datasets of gene expression on a total of 41 paired PTC/normal thyroid tissues. We identified 26 (up and 13 (down L/R pairs coordinately and differentially expressed. The relevance of these L/R pairs was confirmed by performing the same analysis on REarranged during Transfection (RET/PTC1-infected thyrocytes with respect to normal thyrocytes. TGFA/EGFR emerged as one of the most tightly regulated L/R pair. Furthermore, PTC clinical samples analyzed by real-time RT-PCR expressed EGFR transcript levels similar to those of 5 normal thyroid tissues from patients with pathologies other than thyroid cancer, whereas significantly elevated levels of TGFA transcripts were only present in PTCs. Biochemical analysis of PTC cell lines demonstrated the presence of EGFR on the cell membrane and TGFA in conditioned media. Moreover, conditioned medium of the PTC cell line NIM-1 activated EGFR expressed on HeLa cells, culminating in both ERK and AKT phosphorylation. In NIM-1 cells harboring BRAF mutation, TGFA stimulated proliferation, contributing to PI3K/AKT activation independent of MEK/ERK signaling. CONCLUSIONS/SIGNIFICANCE: We compiled a reliable list of L/R pairs associated with PTC and validated the biological role of one of the emerged L/R pair, the TGFA/EGFR, in this cancer, in vitro. These data provide a better understanding of the factors involved in the

  15. C/EBPα Short-Activating RNA Suppresses Metastasis of Hepatocellular Carcinoma through Inhibiting EGFR/β-Catenin Signaling Mediated EMT.

    Directory of Open Access Journals (Sweden)

    Hongbo Huan

    Full Text Available Hepatocellular carcinoma is associated with high mortality, and tumor metastasis is an important reason for poor prognosis. However, metastasis has not been effectively prevented in clinical therapy and the mechanisms underlying metastasis have not been fully characterized. CCAAT/enhancer-binding protein-α (C/EBPα is a transcriptional regulator with an essential role in tumor metastasis. We used short-activating RNAs (saRNA to enhance expression of C/EBPα. Intravenous injection of C/EBPα-saRNA in a nude mouse liver orthotopic xenograft tumor model inhibited intrahepatic and distant metastasis. C/EBPα-saRNA-treated mice showed increased serum levels of albumin and decreased alanine aminotransferase (ALT, glutamic-oxalacetic transaminase (AST, indicating a role of C/EBPα in improving liver function. Migration and invasion were inhibited in hepatoma cell lines transfected with C/EBPα-saRNA. We also observed an inhibition of epithelial-mesenchymal transition (EMT and suppression of epidermal growth factor receptor (EGFR, EGFR phosphorylation, and β-catenin in C/EBPa-saRNA-transfected cells. Our results suggested that C/EBPα-saRNA successfully inhibited HCC metastasis by inhibiting EGFR/β-catenin signaling pathway mediated EMT in vitro and in vivo.

  16. Synthesis, antitumour and antioxidant activities of novel α,β-unsaturated ketones and related heterocyclic analogues: EGFR inhibition and molecular modelling study.

    Science.gov (United States)

    El-Husseiny, Walaa M; El-Sayed, Magda A-A; Abdel-Aziz, Naglaa I; El-Azab, Adel S; Ahmed, Esam R; Abdel-Aziz, Alaa A-M

    2018-12-01

    New α,β-unsaturated ketones 4a,b; 5a-c; and 6a,b; as well as 4-H pyran 7; pyrazoline 8a,b; isoxazoline 9; pyridine 10-11; and quinoline-4-carboxylic acid 12a,b derivatives were synthesized and evaluated for in vitro antitumour activity against HepG2, MCF-7, HeLa, and PC-3 cancer cell lines. Antioxidant activity was investigated by the ability of these compounds to scavenge the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS •+ ). Compounds 6a, 6b, 7, and 8b exhibited potent antitumour activities against all tested cell lines with [IC 50 ] ≅5.5-18.1 µΜ), in addition to significantly high ABTS •+ scavenging activities. In vitro EGFR kinase assay for 6a, 6b, 7, and 8b as the most potent antitumour compounds showed that; compounds 6b, and 7 exhibited worthy EGFR inhibition activity with IC 50 values of 0.56 and 1.6 µM, respectively, while compounds 6a and 8b showed good inhibition activity with IC 50 values of 4.66 and 2.16 µM, respectively, compared with sorafenib reference drug (IC 50  = 1.28 µM). Molecular modelling studies for compounds 6b, 7, and 8b were conducted to exhibit the binding mode towards EGFR kinase, which showed similar interaction with erlotinib.

  17. Epidermal growth factor receptor (EGFR mutation status and Rad51 determine the response of glioblastoma (GBM to multimodality therapy with cetuximab, temozolomide and radiation

    Directory of Open Access Journals (Sweden)

    Phyllis Rachelle Wachsberger

    2013-02-01

    Full Text Available Purpose: EGFR amplification and mutation (i.e., EGFRvIII are found in 40% of primary GBM tumors and are believed to contribute to tumor development and therapeutic resistance. This study was designed to investigate how EGFR mutational status modulates response to multimodality treatment with cetuximab, an anti-EGFR inhibitor, the chemotherapeutic agent, temozolamide (TMZ and radiation therapy (RT Methods and Materials: In vitro and in vivo experiments were performed on two isogenic U87 GBM cell lines: one overexpressing wildtype EGFR (U87wtEGFR and the other overexpressing EGFRvIII (U87EGFRvIII. Results: Xenografts harboring EGFRvIII were more sensitive to TMZ alone and TMZ in combination with RT and/or cetuximab than xenografts expressing wtEGFR. In vitro experiments demonstrated that U87EGFRvIII-expressing tumors appear to harbor defective DNA homologous recombination repair in the form of Rad51 processing, Conclusions: The difference in sensitivity between EGFR-expressing and EGFRvIII-expressing tumors to combined modality treatment may help in the future tailoring of GBM therapy to subsets of patients expressing more or less of the EGFR mutant.

  18. Role of EGFR transactivation in preventing apoptosis in Pseudomonas aeruginosa-infected human corneal epithelial cells.

    Science.gov (United States)

    Zhang, Jing; Li, Hui; Wang, Jinzhao; Dong, Zheng; Mian, Shahzad; Yu, Fu-Shin X

    2004-08-01

    To determine the role of epidermal growth factor (EGF) receptor (EGFR)-mediated signaling pathways in preventing infection-induced apoptosis in human corneal epithelial cells (HCECs). Epithelial monolayers of a telomerase-immortalized HCEC line, HUCL, and primary culture of HCECs were infected with Pseudomonas aeruginosa in the presence of the EGFR inhibitor tyrphostin AG1478, the extracellular signal-regulated kinase (ERK) inhibitor U0126, the phosphoinositide 3-kinase (PI3K) inhibitor LY294002, the heparin-binding EGF-like growth factor (HB-EGF) antagonist CRM197, the HB-EGF neutralizing antibody, or the matrix metalloproteinase inhibitor GM6001. The activation of EGFR was analyzed by immunoprecipitation using EGFR antibodies, followed by Western blot analysis with phosphotyrosine antibody. Phosphorylation of ERK and Akt, a major substrate of PI3K, and generation of cleaved caspase-3 and poly (ADP-ribose) polymerase (PARP) were determined by Western blot analysis. Apoptotic cells were characterized by positive staining of active caspase-3, loss of mitochondrial cytochrome c, and condensation of chromosomes. Apoptosis was also confirmed by measuring caspase-3 activity and assessing the generation of cleaved caspase-3 and PARP. P. aeruginosa infection of HUCL cells resulted in EGFR activation and EGFR-dependent ERK1/2 and PI3K phosphorylation. Inhibition of EGFR, ERK1/2, and PI3K activities with kinase-specific inhibitors (AG1478, U0126, and LY294002, respectively) resulted in an increase in the number of apoptotic cells, in elevated cellular caspase-3 activity, and/or in increased cleaved PARP in P. aeruginosa-infected HUCL cells or primary culture of HCECs. Blocking HB-EGF ectodomain shedding by inhibition of matrix metalloproteinase-mediated proteolysis, downregulation of HB-EGF, or neutralization of its activity retarded infection-induced EGFR transactivation and, as a consequence, increased infection-induced HUCL apoptosis. Bacterial infection of HCECs induces

  19. Role of EGFR Transactivation in Preventing Apoptosis in Pseudomonas aeruginosa–Infected Human Corneal Epithelial Cells

    Science.gov (United States)

    Zhang, Jing; Li, Hui; Wang, Jinzhao; Dong, Zheng; Mian, Shahzad; Yu, Fu-Shin X.

    2009-01-01

    PURPOSE To determine the role of epidermal growth factor (EGF) receptor (EGFR)–mediated signaling pathways in preventing infection-induced apoptosis in human corneal epithelial cells (HCECs). METHODS Epithelial monolayers of a telomerase-immortalized HCEC line, HUCL, and primary culture of HCECs were infected with Pseudomonas aeruginosa in the presence of the EGFR inhibitor tyrphostin AG1478, the extracellular signal-regulated kinase (ERK) inhibitor U0126, the phosphoinositide 3-kinase (PI3K) inhibitor LY294002, the heparin-binding EGF-like growth factor (HB-EGF) antagonist CRM197, the HB-EGF neutralizing antibody, or the matrix metalloproteinase inhibitor GM6001. The activation of EGFR was analyzed by immunoprecipitation using EGFR antibodies, followed by Western blot analysis with phosphotyrosine antibody. Phosphorylation of ERK and Akt, a major substrate of PI3K, and generation of cleaved caspase-3 and poly (ADP-ribose) polymerase (PARP) were determined by Western blot analysis. Apoptotic cells were characterized by positive staining of active caspase-3, loss of mitochondrial cytochrome c, and condensation of chromosomes. Apoptosis was also confirmed by measuring caspase-3 activity and assessing the generation of cleaved caspase-3 and PARP. RESULTS P. aeruginosa infection of HUCL cells resulted in EGFR activation and EGFR-dependent ERK1/2 and PI3K phosphorylation. Inhibition of EGFR, ERK1/2, and PI3K activities with kinase-specific inhibitors (AG1478, U0126, and LY294002, respectively) resulted in an increase in the number of apoptotic cells, in elevated cellular caspase-3 activity, and/or in increased cleaved PARP in P. aeruginosa–infected HUCL cells or primary culture of HCECs. Blocking HB-EGF ectodomain shedding by inhibition of matrix metalloproteinase–mediated proteolysis, downregulation of HB-EGF, or neutralization of its activity retarded infection-induced EGFR transactivation and, as a consequence, increased infection-induced HUCL apoptosis

  20. Sym004, a Novel EGFR Antibody Mixture, Can Overcome Acquired Resistance to Cetuximab1

    Science.gov (United States)

    Iida, Mari; Brand, Toni M; Starr, Megan M; Li, Chunrong; Huppert, Evan J; Luthar, Neha; Pedersen, Mikkel W; Horak, Ivan D; Kragh, Michael; Wheeler, Deric L

    2013-01-01

    The epidermal growth factor receptor (EGFR) is a central regulator of tumor progression in a variety of human cancers. Cetuximab is an anti-EGFR monoclonal antibody that has been approved for head and neck and colorectal cancer treatment, but many patients treated with cetuximab don't respond or eventually acquire resistance. To determine how tumor cells acquire resistance to cetuximab, we previously developed a model of acquired resistance using the non-small cell lung cancer line NCI-H226. These cetuximab-resistant (CtxR) cells exhibit increased steady-state EGFR expression secondary to alterations in EGFR trafficking and degradation and, further, retained dependence on EGFR signaling for enhanced growth potential. Here, we examined Sym004, a novel mixture of antibodies directed against distinct epitopes on the extracellular domain of EGFR, as an alternative therapy for CtxR tumor cells. Sym004 treatment of CtxR clones resulted in rapid EGFR degradation, followed by robust inhibition of cell proliferation and down-regulation of several mitogen-activated protein kinase pathways. To determine whether Sym004 could have therapeutic benefit in vivo, we established de novo CtxR NCI-H226 mouse xenografts and subsequently treated CtxR tumors with Sym004. Sym004 treatment of mice harboring CtxR tumors resulted in growth delay compared to mice continued on cetuximab. Levels of total and phospho-EGFR were robustly decreased in CtxR tumors treated with Sym004. Immunohistochemical analysis of these Sym004-treated xenograft tumors further demonstrated decreased expression of Ki67, and phospho-rpS6, as well as a modest increase in cleaved caspase-3. These results indicate that Sym004 may be an effective targeted therapy for CtxR tumors. PMID:24204198

  1. Interaction between EGFR and EphA2

    DEFF Research Database (Denmark)

    Larsen, Alice Bjerregaard

    2010-01-01

    Enhanced or altered epidermal growth factor receptor (EGFR) activity has been reported in many human cancers and several molecular targeting therapies has been developed. However, despite intense research, therapies targeting EGFR have shown conflicting results in clinical studies, indicating...... the involvement of other important molecular players. Several different EGFR mutations have been reported in cancer, one of which is the cancer specific type III EGFR deletion mutant (EGFRvIII, de2-7EGFR, ΔEGFR). In a global search for EGFR and EGFRvIII regulated genes we identified the receptor tyrosine kinase...... (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...

  2. Interaction between EGFR and EphA2

    DEFF Research Database (Denmark)

    Larsen, Alice Bjerregaard

    2010-01-01

    Enhanced or altered epidermal growth factor receptor (EGFR) activity has been reported in many human cancers and several molecular targeting therapies has been developed. However, despite intense research, therapies targeting EGFR have shown conflicting results in clinical studies, indicating...... the involvement of other important molecular players. Several different EGFR mutations have been reported in cancer, one of which is the cancer specific type III EGFR deletion mutant (EGFRvIII, de2-7EGFR, ¿EGFR). In a global search for EGFR and EGFRvIII regulated genes we identified the receptor tyrosine kinase...... (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...

  3. TNF-driven adaptive response mediates resistance to EGFR inhibition in lung cancer.

    Science.gov (United States)

    Gong, Ke; Guo, Gao; Gerber, David E; Gao, Boning; Peyton, Michael; Huang, Chun; Minna, John D; Hatanpaa, Kimmo J; Kernstine, Kemp; Cai, Ling; Xie, Yang; Zhu, Hong; Fattah, Farjana J; Zhang, Shanrong; Takahashi, Masaya; Mukherjee, Bipasha; Burma, Sandeep; Dowell, Jonathan; Dao, Kathryn; Papadimitrakopoulou, Vassiliki A; Olivas, Victor; Bivona, Trever G; Zhao, Dawen; Habib, Amyn A

    2018-06-01

    Although aberrant EGFR signaling is widespread in cancer, EGFR inhibition is effective only in a subset of non-small cell lung cancer (NSCLC) with EGFR activating mutations. A majority of NSCLCs express EGFR wild type (EGFRwt) and do not respond to EGFR inhibition. TNF is a major mediator of inflammation-induced cancer. We find that a rapid increase in TNF level is a universal adaptive response to EGFR inhibition in NSCLC, regardless of EGFR status. EGFR signaling actively suppresses TNF mRNA levels by inducing expression of miR-21, resulting in decreased TNF mRNA stability. Conversely, EGFR inhibition results in loss of miR-21 and increased TNF mRNA stability. In addition, TNF-induced NF-κB activation leads to increased TNF transcription in a feed-forward loop. Inhibition of TNF signaling renders EGFRwt-expressing NSCLC cell lines and an EGFRwt patient-derived xenograft (PDX) model highly sensitive to EGFR inhibition. In EGFR-mutant oncogene-addicted cells, blocking TNF enhances the effectiveness of EGFR inhibition. EGFR plus TNF inhibition is also effective in NSCLC with acquired resistance to EGFR inhibition. We suggest concomitant EGFR and TNF inhibition as a potentially new treatment approach that could be beneficial for a majority of lung cancer patients.

  4. 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.

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

    International Nuclear Information System (INIS)

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

    2016-01-01

    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

  6. Chlorpyrifos promotes colorectal adenocarcinoma H508 cell growth through the activation of EGFR/ERK1/2 signaling pathway but not cholinergic pathway.

    Science.gov (United States)

    Suriyo, Tawit; Tachachartvanich, Phum; Visitnonthachai, Daranee; Watcharasit, Piyajit; Satayavivad, Jutamaad

    2015-12-02

    Aside from the effects on neuronal cholinergic system, epidemiological studies suggest an association between chlorpyrifos (CPF) exposure and cancer risk. This in vitro study examined the effects of CPF and its toxic metabolite, chlorpyrifos oxon (CPF-O), on the growth of human colorectal adenocarcinoma H508, colorectal adenocarcinoma HT-29, normal colon epithelial CCD841, liver hepatocellular carcinoma HepG2, and normal liver hepatocyte THLE-3 cells. The results showed that CPF (5-100 μM) concentration-dependently increased viability of H508 and CCD841 cells in serum-free conditions. This increasing trend was not found in HT-29, HepG2 and THLE-3 cells. In contrast, CPF-O (50-100 μM) reduced the viability of all cell lines. Cell cycle analysis showed the induction of cells in the S phase, and EdU incorporation assay revealed the induction of DNA synthesis in CPF-treated H508 cells indicating that CPF promotes cell cycle progression. Despite the observation of acetylcholinesterase activity inhibition and reactive oxygen species (ROS) generation, atropine (a non-selective muscarinic acetylcholine receptor antagonist) and N-acetylcysteine (a potent antioxidant) failed to inhibit the growth-promoting effect of CPF. CPF increased the phosphorylation of epidermal growth factor receptor (EGFR) and its downstream effector, extracellular signal regulated kinase (ERK1/2), in H508 cells. AG-1478 (a specific EGFR tyrosine kinase inhibitor) and U0126 (a specific MEK inhibitor) completely mitigated the growth promoting effect of CPF. Altogether, these results suggest that EGFR/ERK1/2 signaling pathway but not cholinergic pathway involves in CPF-induced colorectal adenocarcinoma H508 cell growth. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. Niacin activates the PI3K/Akt cascade via PKC- and EGFR-transactivation-dependent pathways through hydroxyl-carboxylic acid receptor 2.

    Directory of Open Access Journals (Sweden)

    Huawang Sun

    Full Text Available Niacin has been demonstrated to activate a PI3K/Akt signaling cascade to prevent brain damage after stroke and UV-induced skin damage; however, the underlying molecular mechanisms for HCA2-induced Akt activation remain to be elucidated. Using CHO-K1 cells stably expressing HCA2 and A431 cells, a human epidermoid cell line with high levels of endogenous expression of functional HCA2 receptors, we first demonstrated that niacin induced a robust Akt phosphorylation at both Thr308 and Ser473 in a time-dependent fashion, with a maximal activation at 5 min and a subsequent reduction to baseline by 30 min through HCA2, and that the activation was significantly blocked by pertussis toxin. The HCA2-mediated activation of Akt was also significantly inhibited by the PKC inhibitors GF109203x and Go6983 in both cell lines, by the PDGFR-selective inhibitor tyrphostin A9 in CHO-HCA2 cells and by the MMP inhibitor GM6001 and EGFR-specific inhibitor AG1478 in A431 cells. These results suggest that the PKC pathway and PDGFR/EGFR transactivation pathway play important roles in HCA2-mediated Akt activation. Further investigation indicated that PI3K and the Gβγ subunit were likely to play an essential role in HCA2-induced Akt activation. Moreover, Immunobloting analyses using an antibody that recognizes p70S6K1 phosphorylated at Thr389 showed that niacin evoked p70S6K1 activation via the PI3K/Akt pathway. The results of our study provide new insight into the signaling pathways involved in HCA2 activation.

  8. A marked response to icotinib in a patient with large cell neuroendocrine carcinoma harboring an EGFR mutation: A case report.

    Science.gov (United States)

    Wang, Yuehong; Shen, Yi Hong; Ma, Shanni; Zhou, Jianying

    2015-09-01

    The present study reports the case of an 84-year-old male with primary pulmonary large cell neuroendocrine carcinoma (LCNEC) harboring an epidermal growth factor receptor (EGFR) gene mutation that exhibited a long-lasting response to the EGFR-tyrosine kinase inhibitor (EGFR-TKI) icotinib. The patient had an extensive smoking history, a poor performance status, and presented with an irregular mass in the middle lobe of the right lung on computed tomography (CT) and an enlarged left supraclavicular lymph node on physical examination. Right middle lobe bronchial brushing during fiberoptic bronchoscopy identified poorly-differentiated cancer cells. The left supraclavicular lymph node was biopsied and a diagnosis of metastatic LCNEC was determined. Furthermore, an EGFR exon 19 deletion was identified by DNA sequencing. Following diagnosis, icotinib was administered at a dose of 125 mg three times a day. Chest CT scans were performed after 1 month of treatment, which indicated that the tumor was in partial remission. This marked response to icotinib lasted for 8 months. Thus, the present case illustrates the possibility of identifying EGFR mutations in LCNEC and indicates that EGFR-tyrosine kinase inhibitors may be an alternative treatment strategy for patients with LCNEC harboring activating EGFR mutations.

  9. Sapanisertib and Osimertinib in Treating Patients With Stage IV EGFR Mutation Positive Non-small Cell Lung Cancer After Progression on a Previous EGFR Tyrosine Kinase Inhibitor

    Science.gov (United States)

    2018-04-25

    EGFR Activating Mutation; EGFR Exon 19 Deletion Mutation; EGFR NP_005219.2:p.G719X; EGFR NP_005219.2:p.L858R; EGFR NP_005219.2:p.L861Q; EGFR T790M Mutation Negative; Recurrent Non-Small Cell Lung Carcinoma; Stage III Non-Small Cell Lung Cancer AJCC v7; Stage IIIA Non-Small Cell Lung Cancer AJCC v7; Stage IIIB Non-Small Cell Lung Cancer AJCC v7; Stage IV Non-Small Cell Lung Cancer AJCC v7

  10. A polymorphism of EGFR extracellular domain is associated with progression free-survival in metastatic colorectal cancer patients receiving cetuximab-based treatment

    International Nuclear Information System (INIS)

    Gonçalves, Anthony; Turrini, Olivier; Lelong, Bernard; Viens, Patrice; Borg, Jean-Paul; Birnbaum, Daniel; Olschwang, Sylviane; Viret, Frédéric; Esteyries, Séverine; Taylor-Smedra, Brynn; Lagarde, Arnaud; Ayadi, Mounay; Monges, Geneviève; Bertucci, François; Esterni, Benjamin; Delpero, Jean-Robert

    2008-01-01

    Cetuximab, a monoclonal antibody targeting Epidermal Growth Factor Receptor (EGFR), is currently used in metastatic colorectal cancer (mCRC), but predictive factors for therapeutic response are lacking. Mutational status of KRAS and EGFR, and EGFR copy number are potential determinants of cetuximab activity. We analyzed tumor tissues from 32 EGFR-positive mCRC patients receiving cetuximab/irinotecan combination and evaluable for treatment response. EGFR copy number was quantified by fluorescence in situ hybridization (FISH). KRAS exon 1 and EGFR exons coding for extracellular regions were sequenced. Nine patients experienced an objective response (partial response) and 23 were considered as nonresponders (12 with stable disease and 11 with progressive disease). There was no EGFR amplification found, but high polysomy was noted in 2 patients, both of which were cetuximab responders. No EGFR mutations were found but a variant of exon 13 (R521K) was observed in 12 patients, 11 of which achieved objective response or stable disease. Progression-free and overall survivals were significantly better in patients with this EGFR exon 13 variant. KRAS mutations were found in 14 cases. While there was a trend for an increased KRAS mutation frequency in nonresponder patients (12 mutations out of 23, 52%) as compared to responder patients (2 out of 9, 22%), authentic tumor response or long-term disease stabilization was found in KRAS mutated patients. This preliminary study suggests that: an increase in EGFR copy number may be associated with cetuximab response but is a rare event in CRC, KRAS mutations are associated with low response rate but do not preclude any cetuximab-based combination efficacy and EGFR exon 13 variant (R521K) may predict for cetuximab benefit

  11. The E3 ubiquitin ligase NEDD4 mediates cell migration signaling of EGFR in lung cancer cells.

    Science.gov (United States)

    Shao, Genbao; Wang, Ranran; Sun, Aiqin; Wei, Jing; Peng, Ke; Dai, Qian; Yang, Wannian; Lin, Qiong

    2018-02-19

    EGFR-dependent cell migration plays an important role in lung cancer progression. Our previous study observed that the HECT E3 ubiquitin ligase NEDD4 is significantly correlated with tumor metastasis and required for migration and invasion signaling of EGFR in gastric cancer cells. However, how NEDD4 promotes the EGFR-dependent lung cancer cell migration is unknown. This study is to elucidate the mechanism by which NEDD4 mediates the EGFR lung cancer migration signaling. Lentiviral vector-loaded NEDD4 shRNA was used to deplete endogenous NEDD4 in lung cancer cell lines. Effects of the NEDD4 knockdown on the EGFR-dependent or independent lung cancer cell migration were determined using the wound-healing and transwell assays. Association of NEDD4 with activated EGFR was assayed by co-immunoprecipitation. Co-expression of NEDD4 with EGFR or PTEN was determined by immunohistochemical (IHC) staining in 63 lung adenocarcinoma tissue samples. Effects of NEDD4 ectopic expression or knockdown on PTEN ubiquitination and down-regulation, AKT activation and lysosomal secretion were examined using the GST-Uba pulldown assay, immunoblotting, immunofluorescent staining and a human cathepsin B ELISA assay respectively. The specific cathepsin B inhibitor CA-074Me was used for assessing the role of cathepsin B in lung cancer cell migration. Knockdown of NEDD4 significantly reduced EGF-stimulated cell migration in non-small cell lung carcinoma (NSCLC) cells. Co-immunoprecipitation assay found that NEDD4 is associated with EGFR complex upon EGF stimulation, and IHC staining indicates that NEDD4 is co-expressed with EGFR in lung adenocarcinoma tumor tissues, suggesting that NEDD4 might mediate lung cancer cell migration by interaction with the EGFR signaling complex. Interestingly, NEDD4 promotes the EGF-induced cathepsin B secretion, possibly through lysosomal exocytosis, as overexpression of the ligase-dead mutant of NEDD4 impedes lysosomal secretion, and knockdown of NEDD4

  12. 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

    2017-06-15

    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; 23(12); 3139-49. ©2016 AACR . ©2016 American Association for Cancer Research.

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

    International Nuclear Information System (INIS)

    Fedrigo, Carlos A; Rocha, Adriana B da; Grivicich, Ivana; Schunemann, Daniel P; Chemale, Ivan M; Santos, Daiane dos; Jacovas, Thais; Boschetti, Patryck S; Jotz, Geraldo P; Filho, Aroldo Braga

    2011-01-01

    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. 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). 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. These results indicate that the PI3K-Akt and MEK-ERK pathways triggered by EGFr confer GBM radioresistance

  14. Icotinib in Patients with Pretreated Advanced Esophageal Squamous Cell Carcinoma with EGFR Overexpression or EGFR Gene Amplification: A Single-Arm, Multicenter Phase 2 Study.

    NARCIS (Netherlands)

    Huang, J.; Fan, Q.; Lu, P.; Ying, J.; Ma, C.; Liu, W.; Liu, Y.; Tan, F.; Sun, Y

    2016-01-01

    INTRODUCTION: Epidermal growth factor receptor (EGFR) has been reported to be overexpressed and amplified in a high percentage of patients with esophageal squamous cell carcinoma (ESCC). The activity of icotinib, an EGFR tyrosine kinase inhibitor, was assessed in previously treated ESCC with EGFR

  15. p-Benzoquinone initiates non-invasive urothelial cancer through aberrant tyrosine phosphorylation of EGFR, MAP kinase activation and cell cycle deregulation: Prevention by vitamin C

    Directory of Open Access Journals (Sweden)

    Shinjini Ganguly

    Full Text Available According to WHO classification system, non-invasive urothelial carcinoma represents urothelial carcinoma in situ (CIS and dysplasia. Dysplastic urothelium often progresses to CIS that further advances to urothelial carcinoma (UC. The strongest risk factor for UC is cigarette smoking. However, the pathogenesis of cigarette smoke (CS-induced UC is poorly understood. Earlier we had shown that p-benzoquinone (p-BQ, a major toxic quinone derived from p-benzosemiquinone of CS in vivo, is a causative factor for various CS-induced diseases. Here, using a guinea pig model we showed that prolonged treatment with p-BQ led to non-invasive UC, specifically carcinoma in situ (CIS of the renal pelvis and dysplasia in the ureter and bladder. The mechanisms of carcinogenesis were p-BQ-induced oxidative damage and apoptosis that were later suppressed and followed by activation of epidermal growth factor receptor, aberrant phosphorylation of intracellular tyrosine residues, activation of MAP kinase pathway and persistent growth signaling. This was accompanied by deregulation of cell cycle as shown by marked decrease in the expression of p21waf1/cip1 and cyclin D1 proteins as well as hyperphosphorylation of pRb. UC has been characterised by histopathology and immunohistochemistry showing aberrant CK20, increased Ki-67, and marked p53 nuclear immunopositivity with uniformly negative labelling of CD44. Oral supplementation of vitamin C (30 mg/kg body weight/day prevented CIS of the renal pelvis and dysplasia in the ureter and bladder. Since majority of non-invasive UC progresses to invasive cancer with increased risk of mortality, our preclinical study might help to devise effective strategies for early intervention of the disease. Abbreviations: Bax, Bcl-2, CS, DNPH, GAPDH, IARC, p-BQ, p-BSQ, PAHs, PBS, ROS, SDS PAGE, TUNEL, WHO, UC, CIS, EGFR, MAPK, Keywords: p-Benzoquinone, Carcinoma in situ, Dysplasia, Aberrant EGFR activation, Cell cycle deregulation

  16. MITF Modulates Therapeutic Resistance through EGFR Signaling.

    Science.gov (United States)

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

    2015-07-01

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

  17. 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.

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

    Science.gov (United States)

    Choudhary, Kumari Sonal; Rohatgi, Neha; Halldorsson, Skarphedinn; Briem, Eirikur; Gudjonsson, Thorarinn; Gudmundsson, Steinn; Rolfsson, Ottar

    2016-06-01

    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. Nuclear EGFR as a molecular target in cancer

    International Nuclear Information System (INIS)

    Brand, Toni M.; Iida, Mari; Luthar, Neha; Starr, Megan M.; Huppert, Evan J.; Wheeler, Deric L.

    2013-01-01

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

  20. Elucidation of the critical epitope of an anti-EGFR monoclonal antibody EMab-134.

    Science.gov (United States)

    Kaneko, Mika K; Yamada, Shinji; Itai, Shunsuke; Chang, Yao-Wen; Nakamura, Takuro; Yanaka, Miyuki; Kato, Yukinari

    2018-07-01

    The epidermal growth factor receptor (EGFR) is a type-1 transmembrane receptor tyrosine kinase, which activates the downstream signaling cascades in many tumors, such as oral and lung cancers. We previously developed EMab-134, a novel anti-EGFR monoclonal antibody (mAb), which reacts with endogenous EGFR-expressing cancer cell lines and normal cells independent of glycosylation in Western blotting, flow cytometry, and immunohistochemical analysis. EMab-134 showed very high sensitivity (94.7%) to oral squamous cell carcinomas in immunohistochemical analysis. In this study, we performed enzyme-linked immunosorbent assay (ELISA), flow cytometry, and immunohistochemical analysis to determine the epitope of EMab-134. A blocking peptide (375-394 amino acids of EGFR) neutralized the EMab-134 reaction against oral cancer cells in flow cytometry and immunohistochemistry. The minimum epitope of EMab-134 was found to be the 377- RGDSFTHTPP -386 sequence. Our findings can be applied for the production of more functional anti-EGFR mAbs that in turn can be used for antitumor treatments.

  1. Elucidation of the critical epitope of an anti-EGFR monoclonal antibody EMab-134

    Directory of Open Access Journals (Sweden)

    Mika K. Kaneko

    2018-07-01

    Full Text Available The epidermal growth factor receptor (EGFR is a type-1 transmembrane receptor tyrosine kinase, which activates the downstream signaling cascades in many tumors, such as oral and lung cancers. We previously developed EMab-134, a novel anti-EGFR monoclonal antibody (mAb, which reacts with endogenous EGFR-expressing cancer cell lines and normal cells independent of glycosylation in Western blotting, flow cytometry, and immunohistochemical analysis. EMab-134 showed very high sensitivity (94.7% to oral squamous cell carcinomas in immunohistochemical analysis. In this study, we performed enzyme-linked immunosorbent assay (ELISA, flow cytometry, and immunohistochemical analysis to determine the epitope of EMab-134. A blocking peptide (375–394 amino acids of EGFR neutralized the EMab-134 reaction against oral cancer cells in flow cytometry and immunohistochemistry. The minimum epitope of EMab-134 was found to be the 377-RGDSFTHTPP−386 sequence. Our findings can be applied for the production of more functional anti-EGFR mAbs that in turn can be used for antitumor treatments.

  2. Past Decline Versus Current eGFR and Subsequent Mortality Risk

    NARCIS (Netherlands)

    Naimark, David M. J.; Grams, Morgan E.; Matsushita, Kunihiro; Black, Corri; Drion, Iefke; Fox, Caroline S.; Inker, Lesley A.; Ishani, Areef; Jee, Sun Ha; Kitamura, Akihiko; Lea, Janice P.; Nally, Joseph; Peralta, Carmen Alicia; Rothenbacher, Dietrich; Ryu, Seungho; Tonelli, Marcello; Yatsuya, Hiroshi; Coresh, Josef; Gansevoort, Ron T.; Warnock, David G.; Woodward, Mark; de Jong, Paul E.

    A single determination of eGFR associates with subsequent mortality risk. Prior decline in eGFR indicates loss of kidney function, but the relationship to mortality risk is uncertain. We conducted an individual-level meta-analysis of the risk of mortality associated with antecedent eGFR slope,

  3. BAG3 promotes tumour cell proliferation by regulating EGFR signal transduction pathways in triple negative breast cancer.

    Science.gov (United States)

    Shields, Sarah; Conroy, Emer; O'Grady, Tony; McGoldrick, Alo; Connor, Kate; Ward, Mark P; Useckaite, Zivile; Dempsey, Eugene; Reilly, Rebecca; Fan, Yue; Chubb, Anthony; Matallanas, David Gomez; Kay, Elaine W; O'Connor, Darran; McCann, Amanda; Gallagher, William M; Coppinger, Judith A

    2018-03-20

    Triple-negative breast cancer (TNBC), is a heterogeneous disease characterised by absence of expression of the estrogen receptor (ER), progesterone receptor (PR) and lack of amplification of human epidermal growth factor receptor 2 (HER2). TNBC patients can exhibit poor prognosis and high recurrence stages despite early response to chemotherapy treatment. In this study, we identified a pro-survival signalling protein BCL2- associated athanogene 3 (BAG3) to be highly expressed in a subset of TNBC cell lines and tumour tissues. High mRNA expression of BAG3 in TNBC patient cohorts significantly associated with a lower recurrence free survival. The epidermal growth factor receptor (EGFR) is amplified in TNBC and EGFR signalling dynamics impinge on cancer cell survival and disease recurrence. We found a correlation between BAG3 and EGFR expression in TNBC cell lines and determined that BAG3 can regulate tumour cell proliferation, migration and invasion in EGFR expressing TNBC cells lines. We identified an interaction between BAG3 and components of the EGFR signalling networks using mass spectrometry. Furthermore, BAG3 contributed to regulation of proliferation in TNBC cell lines by reducing the activation of components of the PI3K/AKT and FAK/Src signalling subnetworks. Finally, we found that combined targeting of BAG3 and EGFR was more effective than inhibition of EGFR with Cetuximab alone in TNBC cell lines. This study demonstrates a role for BAG3 in regulation of distinct EGFR modules and highlights the potential of BAG3 as a therapeutic target in TNBC.

  4. Antitumor efficacy of triple monoclonal antibody inhibition of epidermal growth factor receptor (EGFR) with MM151 in EGFR-dependent and in cetuximab-resistant human colorectal cancer cells

    Science.gov (United States)

    Napolitano, Stefania; Martini, Giulia; Martinelli, Erika; Della Corte, Carminia Maria; Morgillo, Floriana; Belli, Valentina; Cardone, Claudia; Matrone, Nunzia; Ciardiello, Fortunato; Troiani, Teresa

    2017-01-01

    Purpose We investigated the effect of triple monoclonal antibody inhibition of EGFR to overcome acquired resistance to first generation of anti-EGFR inhibitors. Experimental design MM151 is a mixture of three different monoclonal IgG1 antibodies directed toward three different, non-overlapping, epitopes of the EGFR. We performed an in vivo study by using human CRC cell lines (SW48, LIM 1215 and CACO2) which are sensitive to EGFR inhibitors, in order to evaluate the activity of MM151 as compared to standard anti-EGFR mAbs, such as cetuximab, as single agent or in a sequential strategy of combination MM151 with irinotecan (induction therapy) followed by MM151 with a selective MEK1/2 inhibitor (MEKi) (maintenance therapy). Furthermore, the ability of MM151 to overcome acquired resistance to cetuximab has been also evaluated in cetuximab-refractory CRC models. Results MM151 shown stronger antitumor activity as compared to cetuximab. The maintenance treatment with MM151 plus MEKi resulted the most effective therapeutic modality. In fact, this combination caused an almost complete suppression of tumor growth in SW48, LIM 1215 and CACO2 xenografts model at 30 week. Moreover, in this treatment group, mice with no evidence of tumor were more than double as compared to single agent treated mice. Its superior activity has also been demonstrated, in cetuximab-refractory CRC models. Conclusions These results provide experimental evidence that more efficient and complete EGFR blockade may determine better antitumor activity and could contribute to prevent and/or overcome acquired resistance to EGFR inhibitors. PMID:29137301

  5. Development of Cu-64 labeled EGF for In Vivo PET Imaging of EGFR Expression

    Energy Technology Data Exchange (ETDEWEB)

    Backer, Joseph M.

    2009-07-12

    In this project we proposed to establish feasibility of the development of targeted tracers for radionuclide imaging of epidermal growth factor receptors (EGFR) in cancer patients. The significance and impact of the proposed radiotracers are determined by the crucial role that EGFR plays in many cancers and by the rapid entrance of EGFR-inhibiting drugs into clinic. Clinical experience, however, revealed that only 10-25% of patients that are defined as EGFR-positive by immunohistochemical analysis respond to EGFR-directed therapeutics and there is poor correlation between EGFR immunohistochemistry and treatment. Therefore, for more efficacious use of EGFR-targeting therapeutics, there is a need for information about EGFR activity in patients. We hypothesized that radionuclide imaging of functionally active EGFR will provide such information and would allow for 1) rational patient stratification, 2) rapid monitoring of responses to therapy, and 3) development of personalized treatment regimens. We hypothesized that tracers based epidermal growth factor (EGF), a natural EGFR ligand, as a targeting vector would be particularly advantageous. First, only functionally active and therefore critical for disease progression EGFRs will bind and internalize an EGF-based tracer. Second, continuous internalization of EGF-based tracers by recyclable EGFR would lead to intracellular accumulation of radionuclide and improved signal-to-background ratio. Third, small size of EGF relative to antibodies would facilitate tumor penetration with vastly better non-specific soft tissue and blood clearance rates. Fourth, as a human protein, EGF is not expected to be immunogenic. Finally, at the beginning of this project, we have already engineered and expressed functionally active EGF with an N-terminal Cys-tag for site-specific conjugation of various payloads, including radionuclide chelators. In the Phase I of this project, in collaboration with Dr. Blankenberg’s group at Stanford

  6. Development of Cu-64 labeled EGF for In Vivo PET Imaging of EGFR Expression

    International Nuclear Information System (INIS)

    Backer, Joseph M.

    2009-01-01

    In this project we proposed to establish feasibility of the development of targeted tracers for radionuclide imaging of epidermal growth factor receptors (EGFR) in cancer patients. The significance and impact of the proposed radiotracers are determined by the crucial role that EGFR plays in many cancers and by the rapid entrance of EGFR-inhibiting drugs into clinic. Clinical experience, however, revealed that only 10-25% of patients that are defined as EGFR-positive by immunohistochemical analysis respond to EGFR-directed therapeutics and there is poor correlation between EGFR immunohistochemistry and treatment. Therefore, for more efficacious use of EGFR-targeting therapeutics, there is a need for information about EGFR activity in patients. We hypothesized that radionuclide imaging of functionally active EGFR will provide such information and would allow for (1) rational patient stratification, (2) rapid monitoring of responses to therapy, and (3) development of personalized treatment regimens. We hypothesized that tracers based epidermal growth factor (EGF), a natural EGFR ligand, as a targeting vector would be particularly advantageous. First, only functionally active and therefore critical for disease progression EGFRs will bind and internalize an EGF-based tracer. Second, continuous internalization of EGF-based tracers by recyclable EGFR would lead to intracellular accumulation of radionuclide and improved signal-to-background ratio. Third, small size of EGF relative to antibodies would facilitate tumor penetration with vastly better non-specific soft tissue and blood clearance rates. Fourth, as a human protein, EGF is not expected to be immunogenic. Finally, at the beginning of this project, we have already engineered and expressed functionally active EGF with an N-terminal Cys-tag for site-specific conjugation of various payloads, including radionuclide chelators. In the Phase I of this project, in collaboration with Dr. Blankenberg's group at Stanford

  7. Targeting Signal Transducers and Activators of Transcription-3 (Stat3) As a Novel Strategy In Sensitizing Breast Cancer To Egfr-Targeted Therapy

    National Research Council Canada - National Science Library

    Lo, Hui-Wen

    2008-01-01

    We have performed proposed studies to test the hypothesis that deregulated EGFR and STAT3 pathways synergistically contribute to the malignant biology of breast cancer and that combined uses of anti...

  8. Comparison of a mouse and a novel human scFv-SNAP-auristatin F drug conjugate with potent activity against EGFR-overexpressing human solid tumor cells

    Directory of Open Access Journals (Sweden)

    Woitok M

    2017-07-01

    Full Text Available Mira Woitok,1,2 Diana Klose,1 Stefano Di Fiore,1 Wolfgang Richter,3 Christoph Stein,1 Gerrit Gresch,1 Elena Grieger,1 Stefan Barth,1 Rainer Fischer,1,2 Katharina Kolberg,1,* Judith Niesen1,* 1Fraunhofer Institute for Molecular Biology and Applied Ecology (IME, Aachen, Germany; 2Institute of Molecular Biotechnology (Biology VII, RWTH Aachen University, Aachen, Germany; 3Tube Pharmaceuticals GmbH, Vienna, Austria *These authors contributed equally to this work Abstract: Antibody–drug conjugates (ADCs can deliver toxins to specific targets such as tumor cells. They have shown promise in preclinical/clinical development but feature stoichiometrically undefined chemical linkages, and those based on full-size antibodies achieve only limited tumor penetration. SNAP-tag technology can overcome these challenges by conjugating benzylguanine-modified toxins to single-chain fragment variables (scFvs with 1:1 stoichio­metry while preserving antigen binding. Two (human and mouse scFv-SNAP fusion proteins recognizing the epidermal growth factor receptor (EGFR were expressed in HEK 293T cells. The purified fusion proteins were conjugated to auristatin F (AURIF. Binding activity was confirmed by flow cytometry/immunohistochemistry, and cytotoxic activity was confirmed by cell viability/apoptosis and cell cycle arrest assays, and a novel microtubule dynamics disassembly assay was performed. Both ADCs bound specifically to their target cells in vitro and ex vivo, indicating that the binding activity of the scFv-SNAP fusions was unaffected by conjugation to AURIF. Cytotoxic assays confirmed that the ADCs induced apoptosis and cell cycle arrest at nanomolar concentrations and microtubule disassembly. The SNAP-tag technology provides a platform for the development of novel ADCs with defined conjugation sites and stoichiometry. We achieved the stable and efficient linkage of AURIF to human or murine scFvs using the SNAP-tag technology, offering a strategy to

  9. A Selected Lactobacillus rhamnosus Strain Promotes EGFR-Independent Akt Activation in an Enterotoxigenic Escherichia coli K88-Infected IPEC-J2 Cell Model.

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    Full Text Available Enterotoxigenic Escherichia coli (ETEC are important intestinal pathogens that cause diarrhea in humans and animals. Although probiotic bacteria may protect against ETEC-induced enteric infections, the underlying mechanisms are unknown. In this study, porcine intestinal epithelial J2 cells (IPEC-J2 were pre-incubated with and without Lactobacillus rhamnosus ATCC 7469 and then exposed to F4+ ETEC. Increases in TLR4 and NOD2 mRNA expression were observed at 3 h after F4+ ETEC challenge, but these increases were attenuated by L. rhamnosus treatment. Expression of TLR2 and NOD1 mRNA was up-regulated in cells pre-treated with L. rhamnosus. Pre-treatment with L. rhamnosus counteracted F4+ ETEC-induced increases in TNF-α concentration. Increased PGE2. concentrations were observed in cells infected with F4+ ETEC and in cells treated with L. rhamnosus only. A decrease in phosphorylated epidermal growth factor receptor (EGFR was observed at 3 h after F4+ ETEC challenge in cells treated with L. rhamnosus. Pre-treatment with L. rhamnosus enhanced Akt phosphorylation and increased ZO-1 and occludin protein expression. Our findings suggest that L. rhamnosus protects intestinal epithelial cells from F4+ ETEC-induced damage, partly through the anti-inflammatory response involving synergism between TLR2 and NOD1. In addition, L. rhamnosus promotes EGFR-independent Akt activation, which may activate intestinal epithelial cells in response to bacterial infection, in turn increasing tight junction integrity and thus enhancing the barrier function and restricting pathogen invasion. Pre-incubation with L. rhamnosus was superior to co-incubation in reducing the adhesion of F4+ ETEC to IPEC-J2 cells and subsequently attenuating F4+ ETEC-induced mucin layer destruction and suppressing apoptosis. Our data indicate that a selected L. rhamnosus strain interacts with porcine intestinal epithelial cells to maintain the epithelial barrier and promote intestinal epithelial

  10. A Selected Lactobacillus rhamnosus Strain Promotes EGFR-Independent Akt Activation in an Enterotoxigenic Escherichia coli K88-Infected IPEC-J2 Cell Model.

    Science.gov (United States)

    Zhang, Wei; Zhu, Yao-Hong; Yang, Jin-Cai; Yang, Gui-Yan; Zhou, Dong; Wang, Jiu-Feng

    2015-01-01

    Enterotoxigenic Escherichia coli (ETEC) are important intestinal pathogens that cause diarrhea in humans and animals. Although probiotic bacteria may protect against ETEC-induced enteric infections, the underlying mechanisms are unknown. In this study, porcine intestinal epithelial J2 cells (IPEC-J2) were pre-incubated with and without Lactobacillus rhamnosus ATCC 7469 and then exposed to F4+ ETEC. Increases in TLR4 and NOD2 mRNA expression were observed at 3 h after F4+ ETEC challenge, but these increases were attenuated by L. rhamnosus treatment. Expression of TLR2 and NOD1 mRNA was up-regulated in cells pre-treated with L. rhamnosus. Pre-treatment with L. rhamnosus counteracted F4+ ETEC-induced increases in TNF-α concentration. Increased PGE2. concentrations were observed in cells infected with F4+ ETEC and in cells treated with L. rhamnosus only. A decrease in phosphorylated epidermal growth factor receptor (EGFR) was observed at 3 h after F4+ ETEC challenge in cells treated with L. rhamnosus. Pre-treatment with L. rhamnosus enhanced Akt phosphorylation and increased ZO-1 and occludin protein expression. Our findings suggest that L. rhamnosus protects intestinal epithelial cells from F4+ ETEC-induced damage, partly through the anti-inflammatory response involving synergism between TLR2 and NOD1. In addition, L. rhamnosus promotes EGFR-independent Akt activation, which may activate intestinal epithelial cells in response to bacterial infection, in turn increasing tight junction integrity and thus enhancing the barrier function and restricting pathogen invasion. Pre-incubation with L. rhamnosus was superior to co-incubation in reducing the adhesion of F4+ ETEC to IPEC-J2 cells and subsequently attenuating F4+ ETEC-induced mucin layer destruction and suppressing apoptosis. Our data indicate that a selected L. rhamnosus strain interacts with porcine intestinal epithelial cells to maintain the epithelial barrier and promote intestinal epithelial cell activation in

  11. EGFR Amplification as a Target in Gastroesophageal Adenocarcinoma: Do Anti-EGFR Therapies Deserve a Second Chance?

    Science.gov (United States)

    Strickler, John H

    2018-06-01

    Anti-EGFR therapies have failed to improve survival for unselected patients with metastatic gastroesophageal cancer, but in a subset of patients, EGFR amplification may predict treatment benefit. Maron and colleagues report the clinical activity of anti-EGFR therapies in a cohort of patients with EGFR -amplified metastatic gastroesophageal cancer and utilize serial blood and tumor tissue collection to identify molecular drivers of treatment sensitivity and resistance. Their insights offer a path to overcome technical limitations associated with EGFR amplification and facilitate molecularly targeted therapeutic strategies. Cancer Discov; 8(6); 679-81. ©2018 AACR See related article by Maron et al., p. 696 . ©2018 American Association for Cancer Research.

  12. A Targetable EGFR-Dependent Tumor-Initiating Program in Breast Cancer

    Directory of Open Access Journals (Sweden)

    Paul Savage

    2017-10-01

    Full Text Available Summary: Therapies targeting epidermal growth factor receptor (EGFR have variable and unpredictable responses in breast cancer. Screening triple-negative breast cancer (TNBC patient-derived xenografts (PDXs, we identify a subset responsive to EGFR inhibition by gefitinib, which displays heterogeneous expression of wild-type EGFR. Deep single-cell RNA sequencing of 3,500 cells from an exceptional responder identified subpopulations displaying distinct biological features, where elevated EGFR expression was significantly enriched in a mesenchymal/stem-like cellular cluster. Sorted EGFRhi subpopulations exhibited enhanced stem-like features, including ALDH activity, sphere-forming efficiency, and tumorigenic and metastatic potential. EGFRhi cells gave rise to EGFRhi and EGFRlo cells in primary and metastatic tumors, demonstrating an EGFR-dependent expansion and hierarchical state transition. Similar tumorigenic EGFRhi subpopulations were identified in independent PDXs, where heterogeneous EGFR expression correlated with gefitinib sensitivity. This provides new understanding for an EGFR-dependent hierarchy in TNBC and for patient stratification for therapeutic intervention. : Savage et al. demonstrate that sensitivity to EGFR inhibitor, gefitinib, in triple-negative breast cancer is paradoxically associated with EGFR heterogeneity. Using single-cell RNA sequencing in conjunction with functional assays, they identify TNBC tumors in which EGFR expression identifies cells with tumor-initiating capacity whose proliferative expansion is sensitive to EGFR inhibition. Keywords: breast cancer, tumor heterogeneity, patient-derived xenograft, single-cell RNA sequencing, EGFR inhibition, therapeutic response, tumor-initiating cell, cell hierarchy, BRCA1 mutation

  13. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. 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

    International Nuclear Information System (INIS)

    Cho, Jeong Hyun; Um, Hong Duck; Park, Jong Kuk

    2016-01-01

    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

  15. Spheroid Culture of Head and Neck Cancer Cells Reveals an Important Role of EGFR Signalling in Anchorage Independent Survival.

    Science.gov (United States)

    Braunholz, Diana; Saki, Mohammad; Niehr, Franziska; Öztürk, Merve; Borràs Puértolas, Berta; Konschak, Robert; Budach, Volker; Tinhofer, Ingeborg

    2016-01-01

    In solid tumours millions of cells are shed into the blood circulation each day. Only a subset of these circulating tumour cells (CTCs) survive, many of them presumable because of their potential to form multi-cellular clusters also named spheroids. Tumour cells within these spheroids are protected from anoikis, which allows them to metastasize to distant organs or re-seed at the primary site. We used spheroid cultures of head and neck squamous cell carcinoma (HNSCC) cell lines as a model for such CTC clusters for determining the role of the epidermal growth factor receptor (EGFR) in cluster formation ability and cell survival after detachment from the extra-cellular matrix. The HNSCC cell lines FaDu, SCC-9 and UT-SCC-9 (UT-SCC-9P) as well as its cetuximab (CTX)-resistant sub-clone (UT-SCC-9R) were forced to grow in an anchorage-independent manner by coating culture dishes with the anti-adhesive polymer poly-2-hydroxyethylmethacrylate (poly-HEMA). The extent of apoptosis, clonogenic survival and EGFR signalling under such culture conditions was evaluated. The potential of spheroid formation in suspension culture was found to be positively correlated with the proliferation rate of HNSCC cell lines as well as their basal EGFR expression levels. CTX and gefitinib blocked, whereas the addition of EGFR ligands promoted anchorage-independent cell survival and spheroid formation. Increased spheroid formation and growth were associated with persistent activation of EGFR and its downstream signalling component (MAPK/ERK). Importantly, HNSCC cells derived from spheroid cultures retained their clonogenic potential in the absence of cell-matrix contact. Addition of CTX under these conditions strongly inhibited colony formation in CTX-sensitive cell lines but not their resistant subclones. Altogether, EGFR activation was identified as crucial factor for anchorage-independent survival of HNSCC cells. Targeting EGFR in CTC cluster formation might represent an attractive anti

  16. Epidermal growth factor receptor activation in glioblastoma through novel missense mutations in the extracellular domain.

    Directory of Open Access Journals (Sweden)

    Jeffrey C Lee

    2006-12-01

    Full Text Available Protein tyrosine kinases are important regulators of cellular homeostasis with tightly controlled catalytic activity. Mutations in kinase-encoding genes can relieve the autoinhibitory constraints on kinase activity, can promote malignant transformation, and appear to be a major determinant of response to kinase inhibitor therapy. Missense mutations in the EGFR kinase domain, for example, have recently been identified in patients who showed clinical responses to EGFR kinase inhibitor therapy.Encouraged by the promising clinical activity of epidermal growth factor receptor (EGFR kinase inhibitors in treating glioblastoma in humans, we have sequenced the complete EGFR coding sequence in glioma tumor samples and cell lines. We identified novel missense mutations in the extracellular domain of EGFR in 13.6% (18/132 of glioblastomas and 12.5% (1/8 of glioblastoma cell lines. These EGFR mutations were associated with increased EGFR gene dosage and conferred anchorage-independent growth and tumorigenicity to NIH-3T3 cells. Cells transformed by expression of these EGFR mutants were sensitive to small-molecule EGFR kinase inhibitors.Our results suggest extracellular missense mutations as a novel mechanism for oncogenic EGFR activation and may help identify patients who can benefit from EGFR kinase inhibitors for treatment of glioblastoma.

  17. 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.

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

    International Nuclear Information System (INIS)

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

    2016-01-01

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

  19. Design, Synthesis and Evaluation of Ribose-modified Anilinopyrimidine Derivatives as EGFR Tyrosine Kinase Inhibitors

    Science.gov (United States)

    Hu, Xiuqin; Wang, Disha; Tong, Yi; Tong, Linjiang; Wang, Xia; Zhu, Lili; Xie, Hua; Li, Shiliang; Yang, You; Xu, Yufang

    2017-11-01

    The synthesis of a series of ribose-modified anilinopyrimidine derivatives was efficiently achieved by utilizing DBU or tBuOLi-promoted coupling of ribosyl alcohols with 2,4,5-trichloropyrimidine as key step. Preliminary biological evaluation of this type of compounds as new EGFR tyrosine kinase inhibitors for combating EGFR L858R/T790M mutant associated with drug resistance in the treatment of non-small cell lung cancer revealed that 3-N-acryloyl-5-O-anilinopyrimidine ribose derivative 1a possessed potent and specific inhibitory activity against EGFR L858R/T790M over WT EGFR. Based upon molecular docking studies of the binding mode between compound 1a and EGFR, the distance between the Michael receptor and the pyrimidine scaffold is considered as an important factor for the inhibitory potency and future design of selective EGFR tyrosine kinase inhibitors against EGFR L858R/T790M mutants.

  20. EGFR kinase-dependent and kinase-independent roles in clear cell renal cell carcinoma.

    Science.gov (United States)

    Cossu-Rocca, Paolo; Muroni, Maria R; Sanges, Francesca; Sotgiu, Giovanni; Asunis, Anna; Tanca, Luciana; Onnis, Daniela; Pira, Giovanna; Manca, Alessandra; Dore, Simone; Uras, Maria G; Ena, Sara; De Miglio, Maria R

    2016-01-01

    Epidermal growth factor receptor (EGFR) is associated with progression of many epithelial malignancies and represents a significant therapeutic target. Although clear cell renal cell carcinoma (CCRCC) has been widely investigated for EGFR molecular alterations, genetic evidences of EGFR gene activating mutations and/or gene amplification have been rarely confirmed in the literature. Therefore, until now EGFR-targeted therapies in clinical trials have been demonstrated unsuccessful. New evidence has been given about the interactions between EGFR and the sodium glucose co-transporter-1 (SGLT1) in maintaining the glucose basal intracellular level to favour cancer cell growth and survival; thus a new functional role may be attributed to EGFR, regardless of its kinase activity. To define the role of EGFR in CCRCC an extensive investigation of genetic changes and functional kinase activities was performed in a series of tumors by analyzing the EGFR mutational status and expression profile, together with the protein expression of downstream signaling pathways members. Furthermore, we investigated the co-expression of EGFR and SGLT1 proteins and their relationships with clinic-pathological features in CCRCC. EGFR protein expression was identified in 98.4% of CCRCC. Furthermore, it was described for the first time that SGLT1 is overexpressed in CCRCC (80.9%), and that co-expression with EGFR is appreciable in 79.4% of the tumours. Moreover, the activation of downstream EGFR pathways was found in about 79.4% of SGLT1-positive CCRCCs. The mutational status analysis of EGFR failed to demonstrate mutations on exons 18 to 24 and the presence of EGFR-variantIII (EGFRvIII) in all CCRCCs analyzed. FISH analysis revealed absence of EGFR amplification, and high polysomy of chromosome 7. Finally, the EGFR gene expression profile showed gene overexpression in 38.2% of CCRCCs. Our study contributes to define the complexity of EGFR role in CCRCC, identifying its bivalent kinase

  1. Nimotuzumab enhances temozolomide?induced growth suppression of glioma cells expressing mutant EGFR in vivo

    OpenAIRE

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

    2016-01-01

    Abstract 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 pho...

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

    International Nuclear Information System (INIS)

    Berasain, Carmen; Latasa, María Ujue; Urtasun, Raquel; Goñi, Saioa; Elizalde, María; Garcia-Irigoyen, Oihane; Azcona, María; Prieto, Jesús; Ávila, Matías A.

    2011-01-01

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

  3. Data on mass spectrometry-based proteomics for studying the involvement of CYLD in the ubiquitination events downstream of EGFR activation

    Directory of Open Access Journals (Sweden)

    Virginia Sanchez-Quiles

    2018-06-01

    Full Text Available The present data article corresponds to the proteomic data of the involvement of Cylindromatosis protein (CYLD in the ubiquitination signaling initiated by EGF stimulation. CYLD tumor suppressor protein has Lys63-chain deubiquitinase activity that has been proved essential for the negative regulation of crucial signaling mechanisms, namely the NFkB pathway. Previous results have suggested the involvement of CYLD in the EGF-dependent signal transduction as well, showing its engagement within the tyrosine-phosphorylated complexes formed following the addition of the growth factor. EGFR signaling participates in central cellular processes and its tight regulation, partly through ubiquitination cascades, is decisive for a balanced cellular homeostasis. We carried out the substitution of the endogenous pool of ubiquitin for a His-FLAG-tagged ubiquitin (Stable Ubiquitin Exchange, StUbEx, in combination with the shRNA silencing of CYLD and SILAC-labeling on HeLa cells. The subsequent tandem affinity purification of ubiquitinated proteins in control and CYLD-depleted cells was followed by mass spectrometric analysis. Therefore, we present an unbiased study investigating the impact of CYLD in the EGF-dependent ubiquitination. The data supplied herein is related to the research article entitled “Cylindromatosis tumor suppressor protein (CYLD deubiquitinase is necessary for proper ubiquitination and degradation of the epidermal growth factor receptor” (Sanchez-Quiles et al., 2017 [1]. We provide the associated mass spectrometry raw files, excel tables and gene ontology enrichments. The data have been deposited in the ProteomeXchange with the identifier PXD003423.

  4. [Regulation on EGFR function via its interacting proteins and its potential application].

    Science.gov (United States)

    Zheng, Jun-Fang; Chen, Hui-Min; He, Jun-Qi

    2013-12-01

    Epidermal growth factor receptor (EGFR) is imptortant for cell activities, oncogenesis and cell migration, and EGFR inhibitor can treat cancer efficiently, but its side effects, for example, in skin, limited its usage. On the other hand, EGFR interacting proteins may also lead to oncogenesis and its interacting protein as drug targets can avoid cutaneous side effect, which implies possibly a better outcome and life quality of cancer patients. For the multiple EGFR interaction proteins, B1R enhances Erk/MAPK signaling, while PTPN12, Kek1, CEACAM1 and NHERF repress Erk/MAPK signaling. CaM may alter charge of EGFR juxamembrane domain and regulate activation of PI3K/Akt and PLC-gamma/PKC. STAT1, STAT5b are widely thought to be activated by EGFR, while there is unexpectedly inhibiting sequence within EGFR to repress the activity of STATs. LRIG1 and ACK1 enhance the internalization and degration of EGFR, while NHERF and HIP1 repress it. In this article, proteins interacting with EGFR, their interacting sites and their regulation on EGFR signal transduction will be reviewed.

  5. Cadmium promotes the proliferation of triple-negative breast cancer cells through EGFR-mediated cell cycle regulation

    International Nuclear Information System (INIS)

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

    2015-01-01

    Cadmium (Cd) is a carcinogenic metal which is implicated in breast cancer by epidemiological studies. It is reported to promote breast cancer cell growth in vitro through membrane receptors. The study described here examined Cd-mediated growth of non-metastatic human breast cancer derived cells that lack receptors for estrogen, progesterone, and HER2. Treatment of triple-negative HCC 1937 cells with 0.1–0.5 μM Cd increased cell growth by activation of AKT and ERK. Accelerated cell cycle progression was achieved by increasing the levels of cyclins A, B, and E, as well as those of CDKs 1 and 2. Although triple negative cells lack estrogen receptor, they express high levels of EGFR. Therefore, further studies on HCC 1937 and another triple-negative cell line, HCC 38, were conducted using specific siRNA and an inhibitor of EGFR to determine whether EGFR was responsible for mediating the effect of Cd. The results revealed that in both cell types EGFR was not only activated upon Cd treatment, but was also essential for the downstream activation of AKT and ERK. Based on these observations, it is concluded that, in breast cancer cells lacking estrogen receptor, sub-micromolar concentration of Cd can promote cell proliferation. Furthermore, that EGFR plays a critical role in this process. - Highlights: • Sub-micromolar concentrations of Cd promote cell growth in breast cancer cells that lack ER, PR, and HER2. • The increase in cell number is not due to reduction in apoptosis. • Growth promotion involves AKT and ERK signaling and downstream stimulation of cell cycle progression. • Initiation of cell growth by Cd occurs at the cell membrane and requires the activation of EGFR.

  6. Adaptor protein containing PH domain, PTB domain and leucine zipper (APPL1) regulates the protein level of EGFR by modulating its trafficking

    International Nuclear Information System (INIS)

    Lee, Jae-Rin; Hahn, Hwa-Sun; Kim, Young-Hoon; Nguyen, Hong-Hoa; Yang, Jun-Mo; Kang, Jong-Sun; Hahn, Myong-Joon

    2011-01-01

    Highlights: ► APPL1 regulates the protein level of EGFR in response to EGF stimulation. ► Depletion of APPL1 accelerates the movement of EGF/EGFR from the cell surface to the perinuclear region in response to EGF. ► Knockdown of APPL1 enhances the activity of Rab5. -- Abstract: The EGFR-mediated signaling pathway regulates multiple biological processes such as cell proliferation, survival and differentiation. Previously APPL1 (adaptor protein containing PH domain, PTB domain and leucine zipper 1) has been reported to function as a downstream effector of EGF-initiated signaling. Here we demonstrate that APPL1 regulates EGFR protein levels in response to EGF stimulation. Overexpression of APPL1 enhances EGFR stabilization while APPL1 depletion by siRNA reduces EGFR protein levels. APPL1 depletion accelerates EGFR internalization and movement of EGF/EGFR from cell surface to the perinuclear region in response to EGF treatment. Conversely, overexpression of APPL1 decelerates EGFR internalization and translocation of EGF/EGFR to the perinuclear region. Furthermore, APPL1 depletion enhances the activity of Rab5 which is involved in internalization and trafficking of EGFR and inhibition of Rab5 in APPL1-depleted cells restored EGFR levels. Consistently, APPL1 depletion reduced activation of Akt, the downstream signaling effector of EGFR and this is restored by inhibition of Rab5. These findings suggest that APPL1 is required for EGFR signaling by regulation of EGFR stabilities through inhibition of Rab5.

  7. Expression and clinical value of EGFR in human meningiomas

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    Magnus B. Arnli

    2017-03-01

    Full Text Available Background Meningiomas are common intracranial tumors in humans that frequently recur despite having a predominantly benign nature. Even though these tumors have been shown to commonly express EGFR/c-erbB1 (epidermal growth factor receptor, results from previous studies are uncertain regarding the expression of either intracellular or extracellular domains, cellular localization, activation state, relations to malignancy grade, and prognosis. Aims This study was designed to investigate the expression of the intracellular and extracellular domains of EGFR and of the activated receptor as well as its ligands EGF and TGFα in a large series of meningiomas with long follow-up data, and investigate if there exists an association between antibody expression and clinical and histological data. Methods A series of 186 meningiomas consecutively operated within a 10-year period was included. Tissue microarrays were constructed and immunohistochemically analyzed with antibodies targeting intracellular and extracellular domains of EGFR, phosphorylated receptor, and EGF and TGFα. Expression levels were recorded as a staining index (SI. Results Positive immunoreactivity was observed for all antibodies in most cases. There was in general high SIs for the intracellular domain of EGFR, phosphorylated EGFR, EGF, and TGFα but lower for the extracellular domain. Normal meninges were negative for all antibodies. Higher SIs for the phosphorylated EGFR were observed in grade II tumors compared with grade I (p = 0.018. Survival or recurrence was significantly decreased in the time to recurrence analysis (TTR with high SI-scores of the extracellular domain in a univariable survival analysis (HR 1.152, CI (1.036–1.280, p = 0.009. This was not significant in a multivariable analysis. Expression of the other antigens did not affect survival. Conclusion EGFR is overexpressed and in an activated state in human meningiomas. High levels of ligands also support this

  8. Distinct effects of EGFR inhibitors on epithelial- and mesenchymal-like esophageal squamous cell carcinoma cells.

    Science.gov (United States)

    Yoshioka, Masahiro; Ohashi, Shinya; Ida, Tomomi; Nakai, Yukie; Kikuchi, Osamu; Amanuma, Yusuke; Matsubara, Junichi; Yamada, Atsushi; Miyamoto, Shin'ichi; Natsuizaka, Mitsuteru; Nakagawa, Hiroshi; Chiba, Tsutomu; Seno, Hiroshi; Muto, Manabu

    2017-08-01

    Epidermal growth factor receptor (EGFR) plays a pivotal role in the pathophysiology of esophageal squamous cell carcinoma (ESCC). However, the clinical effects of EGFR inhibitors on ESCC are controversial. This study sought to identify the factors determining the therapeutic efficacy of EGFR inhibitors in ESCC cells. Immortalized-human esophageal epithelial cells (EPC2-hTERT), transformed-human esophageal epithelial cells (T-Epi and T-Mes), and ESCC cells (TE-1, TE-5, TE-8, TE-11, TE-11R, and HCE4) were treated with the EGFR inhibitors erlotinib or cetuximab. Inhibitory effects on cell growth were assessed by cell counting or cell-cycle analysis. The expression levels of genes and proteins such as involucrin and cytokeratin13 (a squamous differentiation marker), E-cadherin, and vimentin were evaluated by real-time polymerase chain reaction or western blotting. To examine whether mesenchymal phenotype influenced the effects of EGFR inhibitors, we treated T-Epi cells with TGF-β1 to establish a mesenchymal phenotype (mesenchymal T-Epi cells). We then compared the effects of EGFR inhibitors on parental T-Epi cells and mesenchymal T-Epi cells. TE-8 (mesenchymal-like ESCC cells)- or TE-11R (epithelial-like ESCC cells)-derived xenograft tumors in mice were treated with cetuximab, and the antitumor effects of EGFR inhibitors were evaluated. Cells were classified as epithelial-like or mesenchymal-like phenotypes, determined by the expression levels of E-cadherin and vimentin. Both erlotinib and cetuximab reduced cell growth and the ratio of cells in cell-cycle S phase in epithelial-like but not mesenchymal-like cells. Additionally, EGFR inhibitors induced squamous cell differentiation (defined as increased expression of involucrin and cytokeratin13) in epithelial-like but not mesenchymal-like cells. We found that EGFR inhibitors did not suppress the phosphorylation of EGFR in mesenchymal-like cells, while EGFR dephosphorylation was observed after treatment with EGFR

  9. XIAP BIR domain suppresses miR-200a expression and subsequently promotes EGFR protein translation and anchorage-independent growth of bladder cancer cell

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    Chao Huang

    2017-01-01

    Full Text Available Abstract Background The X-linked inhibitor of apoptosis protein (XIAP is a well-known potent apoptosis suppressor and also participates in cancer cell biological behaviors, therefore attracting great attentions as a potential antineoplastic therapeutic target for past years. Anti-IAP therapy is reported to be closely related to epidermal growth factor receptor (EGFR expression level. However, whether and how XIAP modulates EGFR expression remains largely unknown. Methods Human XIAP was knockdown with short-hairpin RNA in two different bladder cancer cell lines, T24T and UMUC3. Two XIAP mutants, XIAP ∆BIR (deletion of N-terminal three BIR domains and XIAP ∆RING (deletion of C-terminal RING domain and keeping the function of BIR domains, were generated to determine which domain is involved in regulating EGFR. Results We found here that lacking of XIAP expression resulted in a remarkable suppression of EGFR expression, consequently leading to the deficiency of anchorage-independent cell growth. Further study demonstrated that BIR domain of XIAP was crucial for regulating the EGFR translation by suppressing the transcription and expression of miR-200a. Mechanistic studies indicated that BIR domain activated the protein phosphatase 2 (PP2A activity by decreasing the phosphorylation of PP2A at Tyr307 in its catalytic subunit, PP2A-C. Such activated PP2A prevented the deviant phosphorylation and activation of MAPK kinases/MAPKs, their downstream effector c-Jun, and in turn inhibiting transcription of c-Jun-regulated the miR-200a. Conclusions Our study uncovered a novel function of BIR domain of XIAP in regulating the EGFR translation, providing significant insight into the understanding of the XIAP overexpression in the cancer development and progression, further offering a new theoretical support for using XIAP BIR domain and EGFR as targets for cancer therapy.

  10. Exosome production and its regulation of EGFR during wound healing in renal tubular cells.

    Science.gov (United States)

    Zhou, Xiangjun; Zhang, Wei; Yao, Qisheng; Zhang, Hao; Dong, Guie; Zhang, Ming; Liu, Yutao; Chen, Jian-Kang; Dong, Zheng

    2017-06-01

    Kidney repair following injury involves the reconstitution of a structurally and functionally intact tubular epithelium. Growth factors and their receptors, such as EGFR, are important in the repair of renal tubules. Exosomes are cell-produced small (~100 nm in diameter) vesicles that contain and transfer proteins, lipids, RNAs, and DNAs between cells. In this study, we examined the relationship between exosome production and EGFR activation and the potential role of exosome in wound healing. EGFR activation occurred shortly after scratch wounding in renal tubular cells. Wound repair after scratching was significantly promoted by EGF and suppressed by EGFR inhibitor gefitinib. Interestingly, scratch wounding induced a significant increase of exosome production. The exosome production was decreased by EGF and increased by gefitinib, suggesting a suppressive role of EGFR signaling in exosome production. Conversely, inhibition of exosome release by GW4869 and manumycin A markedly increased EGFR activation and promoted wound healing. Moreover, exosomes derived from scratch-wounding cells could inhibit wound healing. Collectively, the results indicate that wound healing in renal tubular cells is associated with EGFR activation and exosome production. Although EGFR activation promotes wound healing, released exosomes may antagonize EGFR activation and wound healing. Copyright © 2017 the American Physiological Society.

  11. The combi-targeting concept: a novel 3,3-disubstituted nitrosourea with EGFR tyrosine kinase inhibitory properties.

    Science.gov (United States)

    Qiu, Qiyu; Dudouit, Fabienne; Matheson, Stephanie L; Brahimi, Fouad; Banerjee, Ranjita; McNamee, James P; Jean-Claude, Bertrand J

    2003-01-01

    To study the dual mechanism of action of FD137, a 3,3-disubstituted nitrosourea designed to block signaling mediated by the epidermal growth factor receptor (EGFR) on its own and to be hydrolyzed to an inhibitor of EGFR plus a DNA-damaging species. HPLC was used to determine the half-life (t(1/2)) of FD137 and to characterize its derived metabolite FD110. The dual mechanisms of DNA damaging and EGFR tyrosine kinase (TK) targeting were ascertained by the comet assay for DNA damage and by inmunodetection of phosphotyrosine in an ELISA and a whole-cell assay for EGFR-mediated signaling. The antiproliferative effects of the different drugs and their combinations were determined by the sulforhodamine B (SRB) assay. In contrast to BCNU, FD137 significantly blocked EGF-induced EGFR autophosphorylation (IC(50) 4 micro M) in the human solid tumor cell line A431. DNA damage induced by FD137 could only be observed after 24 h exposure, but the level of DNA damage remained 3.6-fold lower than that induced by BCNU. This difference was rationalized by the 160-fold greater stability of FD137 when compared with BCNU in serum-containing medium. Further, degradation of FD137 was accompanied by the slow release of FD110, an extremely potent inhibitor of EGFR TK [IC(50) (EGFR autophosphorylation) <0.3 micro M]. The complex properties of FD137 translated into a 55-fold greater antiproliferative activity than BCNU against the EGFR-overexpressing A431 cells that coexpresses the O(6)-alkylguanine transferase (AGT). Depletion of AGT in these cells by the use of O(6)-benzylguanine (O(6)-BG) enhanced their sensitivity to BCNU by 8-fold, but only by 3-fold to FD137. The results overall suggest that the superior antiproliferative activity of FD137 when compared with BCNU may be associated with its ability to behave as a combination of many species with different mechanisms of action. However, the enhancement of its potency by O(6)-BG suggests that its antiproliferative effect was at least

  12. 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.

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

    International Nuclear Information System (INIS)

    Jorge, S.E.D.C.; Kobayashi, S.S.; Costa, D.B.

    2014-01-01

    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

  14. Epigenetic suppression of EGFR signaling in G-CIMP+ glioblastomas.

    Science.gov (United States)

    Li, Jie; Taich, Zachary J; Goyal, Amit; Gonda, David; Akers, Johnny; Adhikari, Bandita; Patel, Kunal; Vandenberg, Scott; Yan, Wei; Bao, Zhaoshi; Carter, Bob S; Wang, Renzhi; Mao, Ying; Jiang, Tao; Chen, Clark C

    2014-09-15

    The intrinsic signaling cascades and cell states associated with the Glioma CpG Island Methylator Phenotype (G-CIMP) remain poorly understood. Using published mRNA signatures associated with EGFR activation, we demonstrate that G-CIMP+ tumors harbor decreased EGFR signaling using three independent datasets, including the Chinese Glioma Genome Atlas(CGGA; n=155), the REMBRANDT dataset (n=288), and The Cancer Genome Atlas (TCGA; n=406). Additionally, an independent collection of 25 fresh-frozen glioblastomas confirmed lowered pERK levels in G-CIMP+ specimens (pCIMP+ glioblastomas harbored lowered mRNA levels for EGFR and H-Ras. Induction of G-CIMP+ state by exogenous expression of a mutated isocitrate dehydrogenase 1, IDH1-R132H, suppressed EGFR and H-Ras protein expression as well as pERK accumulation in independent glioblastoma models. These suppressions were associated with increased deposition of the repressive histone markers, H3K9me3 and H3K27me3, in the EGFR and H-Ras promoter regions. The IDH1-R132H expression-induced pERK suppression can be reversed by exogenous expression of H-RasG12V. Finally, the G-CIMP+ Ink4a-Arf-/- EGFRvIII glioblastoma line was more resistant to the EGFR inhibitor, Gefitinib, relative to its isogenic G-CIMP- counterpart. These results suggest that G-CIMP epigenetically regulates EGFR signaling and serves as a predictive biomarker for EGFR inhibitors in glioblastoma patients.

  15. Gene expression profiles of lung adenocarcinoma linked to histopathological grading and survival but not to EGF-R status: a microarray study

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    Passlick Bernward

    2010-03-01

    Full Text Available Abstract Background Several different gene expression signatures have been proposed to predict response to therapy and clinical outcome in lung adenocarcinoma. Herein, we investigate if elements of published gene sets can be reproduced in a small dataset, and how gene expression profiles based on limited sample size relate to clinical parameters including histopathological grade and EGFR protein expression. Methods Affymetrix Human Genome U133A platform was used to obtain gene expression profiles of 28 pathologically and clinically annotated adenocarcinomas of the lung. EGFR status was determined by fluorescent in situ hybridization and immunohistochemistry. Results Using unsupervised clustering algorithms, the predominant gene expression signatures correlated with the histopathological grade but not with EGFR protein expression as detected by immunohistochemistry. In a supervised analysis, the signature of high grade tumors but not of EGFR overexpressing cases showed significant enrichment of gene sets reflecting MAPK activation and other potential signaling cascades downstream of EGFR. Out of four different previously published gene sets that had been linked to prognosis, three showed enrichment in the gene expression signature associated with favorable prognosis. Conclusions In this dataset, histopathological tumor grades but not EGFR status were associated with dominant gene expression signatures and gene set enrichment reflecting oncogenic pathway activation, suggesting that high immunohistochemistry EGFR scores may not necessarily be linked to downstream effects that cause major changes in gene expression patterns. Published gene sets showed association with patient survival; however, the small sample size of this study limited the options for a comprehensive validation of previously reported prognostic gene expression signatures.

  16. 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.

  17. Maintenance of EGFR and EGFRvIII expressions in an in vivo and in vitro model of human glioblastoma multiforme

    DEFF Research Database (Denmark)

    Stockhausen, Marie-Thérése; Broholm, Helle; Villingshøj, Mette

    2011-01-01

    Glioblastoma multiforme (GBM) is the most common, and most aggressive primary brain tumor among adults. A vast majority of the tumors express high levels of the epidermal growth factor receptor (EGFR) as a consequence of gene amplification. Furthermore, gene amplification is often associated...... with mutation of EGFR, and the constitutive activated deletion variant EGFRvIII is the most common EGFR mutation found in GBM. Activated EGFR signaling, through overexpression and/or mutation, is involved in increased tumorigenic potential. As such, EGFR is an attractive target for GBM therapy. However......, clinical studies with EGFR inhibitors have shown inconsistent results, and as such, further knowledge regarding the role of EGFR and EGFRvIII in GBM is needed. For this, an appropriate in vivo/in vitro tumor model is required. Here, we report the establishment of an experimental GBM model in which...

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

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    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.

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

    Science.gov (United States)

    Perez, Rolando; Crombet, Tania; de Leon, Joel; Moreno, Ernesto

    2013-01-01

    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.

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

    Directory of Open Access Journals (Sweden)

    Rolando ePerez

    2013-04-01

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

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

    Directory of Open Access Journals (Sweden)

    Young-Ki Bae

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

  2. EGFR overexpressing cells and tumors are dependent on autophagy for growth and survival

    International Nuclear Information System (INIS)

    Jutten, Barry; Keulers, Tom G.; Schaaf, Marco B.E.; Savelkouls, Kim; Theys, Jan; Span, Paul N.; Vooijs, Marc A.; Bussink, Johan; Rouschop, Kasper M.A.

    2013-01-01

    Background and purpose: The epidermal growth factor receptor (EGFR) is overexpressed, amplified or mutated in various human epithelial tumors, and is associated with tumor aggressiveness and therapy resistance. Autophagy activation provides a survival advantage for cells in the tumor microenvironment. In the current study, we assessed the potential of autophagy inhibition (using chloroquine (CQ)) in treatment of EGFR expressing tumors. Material and methods: Quantitative PCR, immunohistochemistry, clonogenic survival, proliferation assays and in vivo tumor growth were used to assess this potential. Results: We show that EGFR overexpressing xenografts are sensitive to CQ treatment and are sensitized to irradiation by autophagy inhibition. In HNSSC xenografts, a correlation between EGFR and expression of the autophagy marker LC3b is observed, suggesting a role for autophagy in EGFR expressing tumors. This observation was substantiated in cell lines, showing high EGFR expressing cells to be more sensitive to CQ addition as reflected by decreased proliferation and survival. Surprisingly high EGFR expressing cells display a lower autophagic flux. Conclusions: The EGFR high expressing cells and tumors investigated in this study are highly dependent on autophagy for growth and survival. Inhibition of autophagy may therefore provide a novel treatment opportunity for EGFR overexpressing tumors

  3. Acquired resistance to EGFR inhibitors: mechanisms and prevention strategies

    International Nuclear Information System (INIS)

    Viloria-Petit, Alicia M.; Kerbel, Robert S.

    2004-01-01

    Potent and specific, or relatively specific, inhibitors of epidermal growth factor receptor (EGFR) signaling, including monoclonal antibodies and small molecular weight compounds, have been successfully developed. Both types of agent have been found to have significant antitumor activity, especially when used in combination with radio- hormone- and chemotherapy in preclinical studies. Because of the potentiation of the conventional drug activity in these combination settings, inhibitors of EGFR signaling have often been referred to as sensitizers for chemotherapy or radiation, as well as drug resistance reversal agents. Phase II clinical trials in head-and-neck as well as lung cancer suggested this concept of chemosensitization might translate into the clinic, but this remains to be definitively proven in randomized, double-blind Phase III trials. Given the extensive preclinical literature on EGFR blocking drugs and the advanced clinical development of such agents, it is surprising that the possibility of development of acquired resistance to the EGFR inhibitors themselves, a common clinical problem with virtually all other currently used anticancer drugs, remains a largely unexplored subject of investigation. Here we summarize some of the possible mechanisms that can result in acquired resistance to EGFR-targeting drugs. Alternative combination therapies to circumvent and delay this problem are suggested

  4. Kinetics of EGFR expression during fractionated irradiation varies between different human squamous cell carcinoma lines in nude mice

    International Nuclear Information System (INIS)

    Eicheler, Wolfgang; Krause, Mechthild; Hessel, Franziska; Zips, Daniel; Baumann, Michael

    2005-01-01

    Background and purpose: Preclinical and clinical data indicate that high pretherapeutic EGFR expression is associated with poor local tumour control, possibly caused by a high repopulation rate of clonogenic cells during radiotherapy in these tumours. Previous data reported from our laboratory showed a correlation between EGFR expression and acceleration of repopulation in poorly differentiated FaDu human squamous cell carcinoma (SCC) during fractionated irradiation. To test whether this is a general phenomenon, two further SCC were investigated in the present study. Patients and methods: GL and UT-SCC-14, two moderately well differentiated and keratinising hSCC, were grown as xenografts in nude mice. Functional data on the repopulation kinetics during fractionated irradiation for these tumour models have been previously determined. The expression of EGFR during fractionation was analysed by immunohistochemistry. Endpoints were the membrane-staining score and the proportion of EGFR-positive cells (EGFR labelling index). Results: Different kinetics of EGFR expression during fractionated RT were found. In UT-SCC-14, EGFR staining score and labelling index increased significantly during radiotherapy. In GL SCC, the EGFR expression was unchanged. Both tumours are characterized by a small but significant repopulation rate during radiotherapy. Conclusions: The expression of EGFR may change significantly during fractionated irradiation. No clear correlation between EGFR expression and the repopulation kinetics of clonogenic tumour cells during fractionated irradiation was found. The changes in EGFR expression during irradiation warrant further investigation on their prognostic implications and on their importance for therapeutic interventions

  5. A calorimetric method to determine water activity.

    Science.gov (United States)

    Björklund, Sebastian; Wadsö, Lars

    2011-11-01

    A calorimetric method to determine water activity covering the full range of the water activity scale is presented. A dry stream of nitrogen gas is passed either over the solution whose activity should be determined or left dry before it is saturated by bubbling through water in an isothermal calorimeter. The unknown activity is in principle determined by comparing the thermal power of vaporization related to the gas stream with unknown activity to that with zero activity. Except for three minor corrections (for pressure drop, non-perfect humidification, and evaporative cooling) the unknown water activity is calculated solely based on the water activity end-points zero and unity. Thus, there is no need for calibration with references with known water activities. The method has been evaluated at 30 °C by measuring the water activity of seven aqueous sodium chloride solutions ranging from 0.1 mol kg(-1) to 3 mol kg(-1) and seven saturated aqueous salt solutions (LiCl, MgCl(2), NaBr, NaCl, KCl, KNO(3), and K(2)SO(4)) with known water activities. The performance of the method was adequate over the complete water activity scale. At high water activities the performance was excellent, which is encouraging as many other methods used for water activity determination have limited performance at high water activities. © 2011 American Institute of Physics

  6. 99mTc labeled anti EGFR Nanobody pentamer for tumor radioimmunoimaging

    International Nuclear Information System (INIS)

    Ding Zhiling; Lan Xiaoli; Li Chongjiao; Pei Zhijun; Zhang Yongxue; Wang Lifei; Gao Bin

    2014-01-01

    Novel Nanobody has small molecular weight and lower affinity. Appropriate polymer would be more suitable for radioimmunoimaging. In this study, we labeled anti EGFR Nanobody pentamer with 99m Tc to prepare tumor targeting imaging agent and to investigate its binding characteristics of tumor cells and tissues in vitro and in vivo, and to explore the feasibility of 99m Tc-EGFR Nanobody pentamer for tumor radioimmunoimaging compared with anti EGFR Nanobody monomer. EGFR Nanobody labeled with 99m Tc through tricarbonyl intermediate. The labeled compounds were purified by an ultra centrifugal filter; The labeling efficiency was determined by thin layer chromatography (TLC), and the radiochemical purity more than 95%. In vitro, 99m Tc-EGFR Nanobody monomer and pentamer have the specific binding capability with EGFR overexpression A431 tumor cell. the binding rate of 99m Tc-EGFR Nanobody monomer higher than that of pentamer (11.32% ± 2.73% vs 5.80% ± 0.92%, P < O.05). In A431 xenografted tumor was clearly displayed after intravenous injection of 99m Tc-EGFR Nanobody pentamer at l.5 h, T/NT maximum was 2.9 (1.5 h), whereas, the tumor tissues was not obviously found using 99m Tc-EGFR Nanobody monomer. The negative EGFR expression OCM-I xenografted tumor was not showed in both monomer and pentamer tracer. The experiment indicated that 99m Tc-EGFR Nanobody pentamer are appropriate for tumor radioimmunoimaging and has the potential value for the further study. (authors)

  7. COPI-mediated retrograde trafficking from the Golgi to the ER regulates EGFR nuclear transport

    International Nuclear Information System (INIS)

    Wang, Ying-Nai; Wang, Hongmei; Yamaguchi, Hirohito; Lee, Hong-Jen; Lee, Heng-Huan; Hung, Mien-Chie

    2010-01-01

    Research highlights: → ARF1 activation is involved in the EGFR transport to the ER and the nucleus. → Assembly of γ-COP coatomer mediates EGFR transport to the ER and the nucleus. → Golgi-to-ER retrograde trafficking regulates nuclear transport of EGFR. -- Abstract: Emerging evidence indicates that cell surface receptors, such as the entire epidermal growth factor receptor (EGFR) family, have been shown to localize in the nucleus. A retrograde route from the Golgi to the endoplasmic reticulum (ER) is postulated to be involved in the EGFR trafficking to the nucleus; however, the molecular mechanism in this proposed model remains unexplored. Here, we demonstrate that membrane-embedded vesicular trafficking is involved in the nuclear transport of EGFR. Confocal immunofluorescence reveals that in response to EGF, a portion of EGFR redistributes to the Golgi and the ER, where its NH 2 -terminus resides within the lumen of Golgi/ER and COOH-terminus is exposed to the cytoplasm. Blockage of the Golgi-to-ER retrograde trafficking by brefeldin A or dominant mutants of the small GTPase ADP-ribosylation factor, which both resulted in the disassembly of the coat protein complex I (COPI) coat to the Golgi, inhibit EGFR transport to the ER and the nucleus. We further find that EGF-dependent nuclear transport of EGFR is regulated by retrograde trafficking from the Golgi to the ER involving an association of EGFR with γ-COP, one of the subunits of the COPI coatomer. Our findings experimentally provide a comprehensive pathway that nuclear transport of EGFR is regulated by COPI-mediated vesicular trafficking from the Golgi to the ER, and may serve as a general mechanism in regulating the nuclear transport of other cell surface receptors.

  8. Epidermal Growth Factor Receptor (EGFR) gene copy number (GCN) correlates with clinical activity of irinotecan-cetuximab in K-RAS wild-type colorectal cancer: a fluorescence in situ (FISH) and chromogenic in situ hybridization (CISH) analysis.

    Science.gov (United States)

    Scartozzi, Mario; Bearzi, Italo; Mandolesi, Alessandra; Pierantoni, Chiara; Loupakis, Fotios; Zaniboni, Alberto; Negri, Francesca; Quadri, Antonello; Zorzi, Fausto; Galizia, Eva; Berardi, Rossana; Biscotti, Tommasina; Labianca, Roberto; Masi, Gianluca; Falcone, Alfredo; Cascinu, Stefano

    2009-08-27

    K-RAS wild type colorectal tumors show an improved response rate to anti-EGFR monoclonal antibodies. Nevertheless 70% to 40% of these patients still does not seem to benefit from this therapeutic approach. FISH EGFR GCN has been previously demonstrated to correlate with clinical outcome of colorectal cancer treated with anti-EGFR monoclonal antibodies. CISH also seemed able to provide accurate EGFR GCN information with the advantage of a simpler and reproducible technique involving immunohistochemistry and light microscopy. Based on these findings we investigated the correlation between both FISH and CISH EGFR GCN and clinical outcome in K-RAS wild-type colorectal cancer treated with irinotecan-cetuximab. Patients with advanced K-RAS wild-type, colorectal cancer receiving irinotecan-cetuximab after failure of irinotecan-based chemotherapy were eligible. A cut-off value for EGFR GCN of 2.6 and 2.12 for FISH and CISH respectively was derived from ROC curve analysis. Forty-four patients were available for analysis. We observed a partial remission in 9 (60%) and 2 (9%) cases with a FISH EGFR GCN >or= 2.6 and CISH EGFR GCN >or= 2.12 and CISH EGFR GCN whereas it was 2.9 and 3.1 months in those with low FISH and CISH EGFR GCN (p = 0.04 and 0.02 respectively). FISH and CISH EGFR GCN may both represent effective tools for a further patients selection in K-RAS wild-type colorectal cancer treated with cetuximab.

  9. Epidermal Growth Factor Receptor (EGFR) gene copy number (GCN) correlates with clinical activity of irinotecan-cetuximab in K-RAS wild-type colorectal cancer: a fluorescence in situ (FISH) and chromogenic in situ hybridization (CISH) analysis

    International Nuclear Information System (INIS)

    Scartozzi, Mario; Galizia, Eva; Berardi, Rossana; Biscotti, Tommasina; Labianca, Roberto; Masi, Gianluca; Falcone, Alfredo; Cascinu, Stefano; Bearzi, Italo; Mandolesi, Alessandra; Pierantoni, Chiara; Loupakis, Fotios; Zaniboni, Alberto; Negri, Francesca; Quadri, Antonello; Zorzi, Fausto

    2009-01-01

    K-RAS wild type colorectal tumors show an improved response rate to anti-EGFR monoclonal antibodies. Nevertheless 70% to 40% of these patients still does not seem to benefit from this therapeutic approach. FISH EGFR GCN has been previously demonstrated to correlate with clinical outcome of colorectal cancer treated with anti-EGFR monoclonal antibodies. CISH also seemed able to provide accurate EGFR GCN information with the advantage of a simpler and reproducible technique involving immunohistochemistry and light microscopy. Based on these findings we investigated the correlation between both FISH and CISH EGFR GCN and clinical outcome in K-RAS wild-type colorectal cancer treated with irinotecan-cetuximab. Patients with advanced K-RAS wild-type, colorectal cancer receiving irinotecan-cetuximab after failure of irinotecan-based chemotherapy were eligible. A cut-off value for EGFR GCN of 2.6 and 2.12 for FISH and CISH respectively was derived from ROC curve analysis. Forty-four patients were available for analysis. We observed a partial remission in 9 (60%) and 2 (9%) cases with a FISH EGFR GCN ≥ 2.6 and < 2.6 respectively (p = 0.002) and in 10 (36%) and 1 (6%) cases with a CISH EGFR GCN ≥ 2.12 and < 2.12 respectively (p = 0.03). Median TTP was 7.7 and 6.4 months in patients showing increased FISH and CISH EGFR GCN whereas it was 2.9 and 3.1 months in those with low FISH and CISH EGFR GCN (p = 0.04 and 0.02 respectively). FISH and CISH EGFR GCN may both represent effective tools for a further patients selection in K-RAS wild-type colorectal cancer treated with cetuximab

  10. Acquired MET expression confers resistance to EGFR inhibition in a mouse model of glioblastoma multiforme.

    Science.gov (United States)

    Jun, H J; Acquaviva, J; Chi, D; Lessard, J; Zhu, H; Woolfenden, S; Bronson, R T; Pfannl, R; White, F; Housman, D E; Iyer, L; Whittaker, C A; Boskovitz, A; Raval, A; Charest, A

    2012-06-21

    Glioblastoma multiforme (GBM) is an aggressive brain tumor for which there is no cure. Overexpression of wild-type epidermal growth factor receptor (EGFR) and loss of the tumor suppressor genes Ink4a/Arf and PTEN are salient features of this deadly cancer. Surprisingly, targeted inhibition of EGFR has been clinically disappointing, demonstrating an innate ability for GBM to develop resistance. Efforts at modeling GBM in mice using wild-type EGFR have proven unsuccessful to date, hampering endeavors at understanding molecular mechanisms of therapeutic resistance. Here, we describe a unique genetically engineered mouse model of EGFR-driven gliomagenesis that uses a somatic conditional overexpression and chronic activation of wild-type EGFR in cooperation with deletions in the Ink4a/Arf and PTEN genes in adult brains. Using this model, we establish that chronic activation of wild-type EGFR with a ligand is necessary for generating tumors with histopathological and molecular characteristics of GBMs. We show that these GBMs are resistant to EGFR kinase inhibition and we define this resistance molecularly. Inhibition of EGFR kinase activity using tyrosine kinase inhibitors in GBM tumor cells generates a cytostatic response characterized by a cell cycle arrest, which is accompanied by a substantial change in global gene expression levels. We demonstrate that an important component of this pattern is the transcriptional activation of the MET receptor tyrosine kinase and that pharmacological inhibition of MET overcomes the resistance to EGFR inhibition in these cells. These findings provide important new insights into mechanisms of resistance to EGFR inhibition and suggest that inhibition of multiple targets will be necessary to provide therapeutic benefit for GBM patients.

  11. Epidermal Growth Factor Receptor (EGFR gene copy number (GCN correlates with clinical activity of irinotecan-cetuximab in K-RAS wild-type colorectal cancer: a fluorescence in situ (FISH and chromogenic in situ hybridization (CISH analysis

    Directory of Open Access Journals (Sweden)

    Scartozzi Mario

    2009-08-01

    Full Text Available Abstract Background K-RAS wild type colorectal tumors show an improved response rate to anti-EGFR monoclonal antibodies. Nevertheless 70% to 40% of these patients still does not seem to benefit from this therapeutic approach. FISH EGFR GCN has been previously demonstrated to correlate with clinical outcome of colorectal cancer treated with anti-EGFR monoclonal antibodies. CISH also seemed able to provide accurate EGFR GCN information with the advantage of a simpler and reproducible technique involving immunohistochemistry and light microscopy. Based on these findings we investigated the correlation between both FISH and CISH EGFR GCN and clinical outcome in K-RAS wild-type colorectal cancer treated with irinotecan-cetuximab. Methods Patients with advanced K-RAS wild-type, colorectal cancer receiving irinotecan-cetuximab after failure of irinotecan-based chemotherapy were eligible. A cut-off value for EGFR GCN of 2.6 and 2.12 for FISH and CISH respectively was derived from ROC curve analysis. Results Forty-four patients were available for analysis. We observed a partial remission in 9 (60% and 2 (9% cases with a FISH EGFR GCN ≥ 2.6 and Conclusion FISH and CISH EGFR GCN may both represent effective tools for a further patients selection in K-RAS wild-type colorectal cancer treated with cetuximab.

  12. The phosphatase inhibitor menadione (vitamin K3) protects cells from EGFR inhibition by erlotinib and cetuximab.

    Science.gov (United States)

    Perez-Soler, Roman; Zou, Yiyu; Li, Tianhong; Ling, Yi He

    2011-11-01

    Skin toxicity is the main side effect of epidermal growth factor receptor (EGFR) inhibitors, often leading to dose reduction or discontinuation. We hypothesized that phosphatase inhibition in the skin keratinocytes may prevent receptor dephosphorylation caused by EGFR inhibitors and be used as a new potential strategy for the prevention or treatment of this side effect. Menadione (Vitamin K3) was used as the prototype compound to test our hypothesis. HaCat human skin keratinocyte cells and A431 human squamous carcinoma cells were used. EGFR inhibition was measured by Western blotting and immunofluorescence. Phosphatase inhibition and reactive oxygen species (ROS) generation were measured by standard ELISA and fluorescence assays. Menadione caused significant and reversible EGFR activation in a dose-dependent manner starting at nontoxic concentrations. EGFR activation by menadione was associated with reversible protein tyrosine phosphatase inhibition, which seemed to be mediated by ROS generation as exposure to antioxidants prevented both menadione-induced ROS generation and phosphatase inhibition. Short-term coincubation of cells with nontoxic concentrations of menadione and the EGFR inhibitors erlotinib or cetuximab prevented EGFR dephosphorylation. Seventy-two-hour coincubation of cells with the highest nontoxic concentration of menadione and erlotinib provided for a fourfold cell growth inhibitory protection in HaCat human keratinocyte cells. Menadione at nontoxic concentrations causes EGFR activation and prevents EGFR dephosphorylation by erlotinib and cetuximab. This effect seems to be mediated by ROS generation and secondary phosphatase inhibition. Mild oxidative stress in skin keratinocytes by topical menadione may protect the skin from the toxicity secondary to EGFR inhibitors without causing cytotoxicity. ©2011 AACR

  13. Determination of phosphorus using derivative neutron activation

    International Nuclear Information System (INIS)

    Scindia, Y.M.; Nair, A.G.C.; Reddy, A.V.R.; Manohar, S.B.

    2002-01-01

    For the determination of phosphorus in different matrices, the derivative neutron activation analysis is especially applicable to aqueous samples, since the conventional neutron activation analysis is not useful for the determination of phosphorus. Phosphorus when reacted with ammonium molybdate 4 hydrate and ammonium metavanadate forms molybdo vanado phosphoric acid. This complex is preconcentrated by extracting into methyl isobutyl ketone. The organic phase containing the molybdo vanado phosphoric acid is neutron activated and the phosphorus is determined through the activation product of 52 V. Preparation of this complex, its stoichiometry, application to trace level determination of phosphorus and improved detection limit are discussed. This method was applied for the analysis of industrial effluent samples. (author)

  14. MLH1 V384D polymorphism associates with poor response to EGFR tyrosine kinase inhibitors in patients with EGFR L858R-positive lung adenocarcinoma.

    Science.gov (United States)

    Chiu, Chao-Hua; Ho, Hsiang-Ling; Doong, Howard; Yeh, Yi-Chen; Chen, Mei-Yu; Chou, Teh-Ying; Tsai, Chun-Ming

    2015-04-10

    A significant fraction of patients with lung adenocarcinomas harboring activating epidermal growth factor receptor (EGFR) mutations do not experience clinical benefits from EGFR tyrosine kinase inhibitor (TKI) therapy. Using next-generation sequencing, we screened 739 mutation hotspots in 46 cancer-related genes in EGFR L858R-mutant lung adenocarcinomas from 29 patients who received EGFR-TKI therapy; 13 had short ( 1 year) progression-free survival (PFS). We discovered MLH1 V384D as a genetic variant enriched in the group of patients with short PFS. Next, we investigated this genetic variation in 158 lung adenocarcinomas with the EGFR L858R mutation and found 14 (8.9%) patients had MLH1 V384D; available blood or non-tumor tissues from patients were also tested positive for MLH1 V384D. Patients with MLH1 V384D had a significantly shorter median PFS than those without (5.1 vs. 10.6 months; P= 0.001). Multivariate analysis showed that MLH1 V384D polymorphism was an independent predictor for a reduced PFS time (hazard ratio, 3.5; 95% confidence interval, 1.7 to 7.2; P= 0.001). In conclusion, MLH1 V384D polymorphism is associated with primary resistance to EGFR-TKIs in patients with EGFR L858R-positive lung adenocarcinoma and may potentially be a novel biomarker to guide treatment decisions.

  15. Correlation of EGFR expression, gene copy number and clinicopathological status in NSCLC.

    Science.gov (United States)

    Gaber, Rania; Watermann, Iris; Kugler, Christian; Reinmuth, Nils; Huber, Rudolf M; Schnabel, Philipp A; Vollmer, Ekkehard; Reck, Martin; Goldmann, Torsten

    2014-09-17

    Epidermal Growth Factor Receptor (EGFR) targeting therapies are currently of great relevance for the treatment of lung cancer. For this reason, in addition to mutational analysis immunohistochemistry (IHC) of EGFR in lung cancer has been discussed for the decision making of according therapeutic strategies. The aim of this study was to obtain standardization of EGFR-expression methods for the selection of patients who might benefit of EGFR targeting therapies. As a starting point of a broad investigation, aimed at elucidating the expression of EGFR on different biological levels, four EGFR specific antibodies were analyzed concerning potential differences in expression levels by Immunohistochemistry (IHC) and correlated with fluorescence in situ hybridization (FISH) analysis and clinicopathological data. 206 tumor tissues were analyzed in a tissue microarray format employing immunohistochemistry with four different antibodies including Dako PharmDx kit (clone 2-18C9), clone 31G7, clone 2.1E1 and clone SP84 using three different scoring methods. Protein expression was compared to FISH utilizing two different probes. EGFR protein expression determined by IHC with Dako PharmDx kit, clone 31G7 and clone 2.1E1 (p ≤ 0.05) correlated significantly with both FISH probes independently of the three scoring methods; best correlation is shown for 31G7 using the scoring method that defined EGFR positivity when ≥ 10% of the tumor cells show membranous staining of moderate and severe intensity (p=0.001). Overall, our data show differences in EGFR expression determined by IHC, due to the applied antibody. Highest concordance with FISH is shown for antibody clone 31G7, evaluated with score B (p=0.001). On this account, this antibody clone might by utilized for standard evaluation of EGFR expression by IHC. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_165.

  16. Reovirus exerts potent oncolytic effects in head and neck cancer cell lines that are independent of signalling in the EGFR pathway

    International Nuclear Information System (INIS)

    Twigger, Katie; Coffey, Matt; Thompson, Brad; Jebar, Adel; Errington, Fiona; Melcher, Alan A; Vile, Richard G; Pandha, Hardev S; Harrington, Kevin J; Roulstone, Victoria; Kyula, Joan; Karapanagiotou, Eleni M; Syrigos, Konstantinos N; Morgan, Richard; White, Christine; Bhide, Shreerang; Nuovo, Gerard

    2012-01-01

    Reovirus exploits aberrant signalling downstream of Ras to mediate tumor-specific oncolysis. Since ~90% squamous cell carcinomas of the head and neck (SCCHN) over-express EGFR and SCCHN cell lines are sensitive to oncolytic reovirus, we conducted a detailed analysis of the effects of reovirus in 15 head and neck cancer cell lines. Both pre- and post-entry events were studied in an attempt to define biomarkers predictive of sensitivity/resistance to reovirus. In particular, we analysed the role of EGFR/Ras signalling in determining virus-mediated cytotoxicity in SCCHN. To test whether EGFR pathway activity was predictive of increased sensitivity to reovirus, correlative analyses between reoviral IC50 by MTT assay and EGFR levels by western blot and FACS were conducted. Inhibition or stimulation of EGFR signalling were analysed for their effect on reoviral oncolysis by MTT assay, and viral growth by TCID50 assay. We next analysed the effects of inhibiting signalling downstream of Ras, by specific inhibitors of p38MAPK, PI3-K or MEK, on reoviral killing examined by MTT assay. The role of PKR in reoviral killing was also determined by blockade of PKR using 2-aminopurine and assaying for cell survival by MTT assay. The apoptotic response of SCCHN to reovirus was examined by western blot analysis of caspase 3 cleavage. Correlative analyses between reoviral sensitivity and EGFR levels revealed no association. Intermediate sub-viral and core particles showed the same infectivity/cytotoxicity as intact reovirus. Therefore, sensitivity was not determined by cell entry. In 4 cell lines, oncolysis and viral growth were both unaffected by inhibition or stimulation of EGFR signalling. Inhibition of signalling downstream of Ras did not abrogate reoviral oncolysis and, in addition, modulation of PKR using 2-aminopurine did not alter reovirus sensitivity in resistant cell lines. Caspase 3 cleavage was not detected in infected cells and oncolysis was observed in pan

  17. Prevention of Bronchial Hyperplasia by EGFR Pathway Inhibitors in an Organotypic Culture Model

    Science.gov (United States)

    Lee, Jangsoon; Ryu, Seung-Hee; Kang, Shin Myung; Chung, Wen-Cheng; Gold, Kathryn Ann; Kim, Edward S.; Hittelman, Walter N.; Hong, Waun Ki; Koo, Ja Seok

    2011-01-01

    Lung cancer is the leading cause of cancer-related mortality worldwide. Early detection or prevention strategies are urgently needed to increase survival. Hyperplasia is the first morphologic change that occurs in the bronchial epithelium during lung cancer development, followed by squamous metaplasia, dysplasia, carcinoma in situ, and invasive tumor. The current study was designed to determine the molecular mechanisms that control bronchial epithelium hyperplasia. Using primary normal human tracheobronchial epithelial (NHTBE) cells cultured using the 3-dimensional organotypic method, we found that the epidermal growth factor receptor (EGFR) ligands EGF, transforming growth factor-alpha, and amphiregulin induced hyperplasia, as determined by cell proliferation and multilayered epithelium formation. We also found that EGF induced increased cyclin D1 expression, which plays a critical role in bronchial hyperplasia; this overexpression was mediated by activating the mitogen-activated protein kinase pathway but not the phosphoinositide 3-kinase/Akt signaling pathway. Erlotinib, an EGFR tyrosine kinase inhibitor, and U0126, a MEK inhibitor, completely inhibited EGF-induced hyperplasia. Furthermore, a promoter analysis revealed that the activator protein-1 transcription factor regulates EGF-induced cyclin D1 overexpression. Activator protein-1 depletion using siRNA targeting its c-Jun component completely abrogated EGF-induced cyclin D1 expression. In conclusion, we demonstrated that bronchial hyperplasia can be modeled in vitro using primary NHTBE cells maintained in a 3-dimensional (3-D) organotypic culture. EGFR and MEK inhibitors completely blocked EGF-induced bronchial hyperplasia, suggesting that they have a chemopreventive role. PMID:21505178

  18. Molecular determinants of epidermal growth factor binding: a molecular dynamics study.

    Directory of Open Access Journals (Sweden)

    Jeffrey M Sanders

    Full Text Available The epidermal growth factor receptor (EGFR is a member of the receptor tyrosine kinase family that plays a role in multiple cellular processes. Activation of EGFR requires binding of a ligand on the extracellular domain to promote conformational changes leading to dimerization and transphosphorylation of intracellular kinase domains. Seven ligands are known to bind EGFR with affinities ranging from sub-nanomolar to near micromolar dissociation constants. In the case of EGFR, distinct conformational states assumed upon binding a ligand is thought to be a determining factor in activation of a downstream signaling network. Previous biochemical studies suggest the existence of both low affinity and high affinity EGFR ligands. While these studies have identified functional effects of ligand binding, high-resolution structural data are lacking. To gain a better understanding of the molecular basis of EGFR binding affinities, we docked each EGFR ligand to the putative active state extracellular domain dimer and 25.0 ns molecular dynamics simulations were performed. MM-PBSA/GBSA are efficient computational approaches to approximate free energies of protein-protein interactions and decompose the free energy at the amino acid level. We applied these methods to the last 6.0 ns of each ligand-receptor simulation. MM-PBSA calculations were able to successfully rank all seven of the EGFR ligands based on the two affinity classes: EGF>HB-EGF>TGF-α>BTC>EPR>EPG>AR. Results from energy decomposition identified several interactions that are common among binding ligands. These findings reveal that while several residues are conserved among the EGFR ligand family, no single set of residues determines the affinity class. Instead we found heterogeneous sets of interactions that were driven primarily by electrostatic and Van der Waals forces. These results not only illustrate the complexity of EGFR dynamics but also pave the way for structure-based design of

  19. Quantitative PET of EGFR expression in xenograft-bearing mice using {sup 64}Cu-labeled cetuximab, a chimeric anti-EGFR monoclonal antibody

    Energy Technology Data Exchange (ETDEWEB)

    Cai, Weibo; Chen, Kai; He, Lina; Cao, Qizhen; Chen, Xiaoyuan [Stanford University School of Medicine, The Molecular Imaging Program at Stanford (MIPS), Department of Radiology and Bio-X Program, Stanford, CA (United States); Koong, Albert [Stanford University School of Medicine, Department of Radiation Oncology, Stanford, CA (United States)

    2007-06-15

    Cetuximab, a chimeric monoclonal antibody targeting epidermal growth factor receptor (EGFR) on the surface of cancer cells, was approved by the FDA to treat patients with metastatic colorectal cancer. It is currently also in advanced-stage development for the treatment of several other solid tumors. Here we report for the first time the quantitative positron emission tomography (PET) imaging of EGFR expression in xenograft-bearing mice using {sup 64}Cu-labeled cetuximab. We conjugated cetuximab with macrocyclic chelating agent 1,4,7,10-tetraazadodecane-N,N',N'',N'''-tetraacetic acid (DOTA), labeled with {sup 64}Cu, and tested the resulting {sup 64}Cu-DOTA-cetuximab in seven xenograft tumor models. The tracer uptake measured by PET was correlated with the EGFR expression quantified by western blotting. The estimated human dosimetry based on the PET data in Sprague-Dawley rats was also calculated. MicroPET imaging showed that {sup 64}Cu-DOTA-cetuximab had increasing tumor activity accumulation over time in EGFR-positive tumors but relatively low uptake in EGFR-negative tumors at all times examined (<5%ID/g). There was a good correlation (R {sup 2} = 0.80) between the tracer uptake (measured by PET) and the EGFR expression level (measured by western blotting). Human dosimetry estimation indicated that the tracer may be safely administered to human patients for tumor diagnosis, with the dose-limiting organ being the liver. The success of EGFR-positive tumor imaging using {sup 64}Cu-DOTA-cetuximab can be translated into the clinic to characterize the pharmacokinetics, to select the right population of patients for EGFR-targeted therapy, to monitor the therapeutic efficacy of anti-EGFR treatment, and to optimize the dosage of either cetuximab alone or cetuximab in combination with other therapeutic agents. (orig.)

  20. Quantitative PET of EGFR expression in xenograft-bearing mice using 64Cu-labeled cetuximab, a chimeric anti-EGFR monoclonal antibody

    International Nuclear Information System (INIS)

    Cai, Weibo; Chen, Kai; He, Lina; Cao, Qizhen; Chen, Xiaoyuan; Koong, Albert

    2007-01-01

    Cetuximab, a chimeric monoclonal antibody targeting epidermal growth factor receptor (EGFR) on the surface of cancer cells, was approved by the FDA to treat patients with metastatic colorectal cancer. It is currently also in advanced-stage development for the treatment of several other solid tumors. Here we report for the first time the quantitative positron emission tomography (PET) imaging of EGFR expression in xenograft-bearing mice using 64 Cu-labeled cetuximab. We conjugated cetuximab with macrocyclic chelating agent 1,4,7,10-tetraazadodecane-N,N',N'',N'''-tetraacetic acid (DOTA), labeled with 64 Cu, and tested the resulting 64 Cu-DOTA-cetuximab in seven xenograft tumor models. The tracer uptake measured by PET was correlated with the EGFR expression quantified by western blotting. The estimated human dosimetry based on the PET data in Sprague-Dawley rats was also calculated. MicroPET imaging showed that 64 Cu-DOTA-cetuximab had increasing tumor activity accumulation over time in EGFR-positive tumors but relatively low uptake in EGFR-negative tumors at all times examined ( 2 0.80) between the tracer uptake (measured by PET) and the EGFR expression level (measured by western blotting). Human dosimetry estimation indicated that the tracer may be safely administered to human patients for tumor diagnosis, with the dose-limiting organ being the liver. The success of EGFR-positive tumor imaging using 64 Cu-DOTA-cetuximab can be translated into the clinic to characterize the pharmacokinetics, to select the right population of patients for EGFR-targeted therapy, to monitor the therapeutic efficacy of anti-EGFR treatment, and to optimize the dosage of either cetuximab alone or cetuximab in combination with other therapeutic agents. (orig.)

  1. Epidermal Growth Factor Receptor Mutation (EGFR) Testing for Prediction of Response to EGFR-Targeting Tyrosine Kinase Inhibitor (TKI) Drugs in Patients with Advanced Non-Small-Cell Lung Cancer: An Evidence-Based Analysis.

    Science.gov (United States)

    2010-01-01

    deaths in Ontario. Those with unresectable or advanced disease are commonly treated with concurrent chemoradiation or platinum-based combination chemotherapy. Although response rates to cytotoxic chemotherapy for advanced NSCLC are approximately 30 to 40%, all patients eventually develop resistance and have a median survival of only 8 to 10 months. Treatment for refractory or relapsed disease includes single-agent treatment with docetaxel, pemetrexed or EGFR-targeting TKIs (gefitinib, erlotinib). TKIs disrupt EGFR signaling by competing with adenosine triphosphate (ATP) for the binding sites at the tyrosine kinase (TK) domain, thus inhibiting the phosphorylation and activation of EGFRs and the downstream signaling network. Gefitinib and erlotinib have been shown to be either non-inferior or superior to chemotherapy in the first- or second-line setting (gefitinib), or superior to placebo in the second- or third-line setting (erlotinib). Certain patient characteristics (adenocarcinoma, non-smoking history, Asian ethnicity, female gender) predict for better survival benefit and response to therapy with TKIs. In addition, the current body of evidence shows that somatic mutations in the EGFR gene are the most robust biomarkers for EGFR-targeting therapy selection. Drugs used in this therapy, however, can be costly, up to C$ 2000 to C$ 3000 per month, and they have only approximately a 10% chance of benefiting unselected patients. For these reasons, the predictive value of EGFR mutation testing for TKIs in patients with advanced NSCLC needs to be determined. EGFR MUTATION TESTING The EGFR gene sequencing by polymerase chain reaction (PCR) assays is the most widely used method for EGFR mutation testing. PCR assays can be performed at pathology laboratories across Ontario. According to experts in the province, sequencing is not currently done in Ontario due to lack of adequate measurement sensitivity. A variety of new methods have been introduced to increase the measurement

  2. Resistance to EGFR inhibitors in non-small cell lung cancer: Clinical management and future perspectives.

    Science.gov (United States)

    Tomasello, Chiara; Baldessari, Cinzia; Napolitano, Martina; Orsi, Giulia; Grizzi, Giulia; Bertolini, Federica; Barbieri, Fausto; Cascinu, Stefano

    2018-03-01

    In the last few years, the development of targeted therapies for non-small cell lung cancer (NSCLC) expressing oncogenic driver mutations (e.g. EGFR) has changed the clinical management and the survival outcomes of this specific minority of patients. Several phase III trials demonstrated the superiority of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) over chemotherapy in EGFR-mutant NSCLC patients. However, in the vast majority of cases EGFR TKIs lose their clinical activity within 8-12 months. Many genetic aberrations have been described as possible mechanisms of EGFR TKIs acquired resistance and can be clustered in four main sub-groups: 1. Development of secondary EGFR mutations; 2. Activation of parallel signaling pathways; 3. Histological transformation; 4. Activation of downstream signaling pathways. In this review we will describe the molecular alterations underlying each of these EGFR TKIs resistance mechanisms, focusing on the currently available and future therapeutic strategies to overcome these phenomena. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Association Between Environmental Tobacco Smoke Exposure and the Occurrence of EGFR Mutations and ALK Rearrangements in Never-smokers With Non-Small-cell Lung Cancer: Analyses From a Prospective Multinational ETS Registry.

    Science.gov (United States)

    Soo, Ross A; Kubo, Akihito; Ando, Masahiko; Kawaguchi, Tomoya; Ahn, Myung-Ju; Ou, Sai-Hong Ignatius

    2017-09-01

    Molecular studies have demonstrated actionable driver oncogene alterations are more frequent in never-smokers with non-small-cell lung cancer (NSCLC). The etiology of these driver oncogenes in patients with NSCLC remains unknown, and environmental tobacco smoke (ETS) is a potential cause in these cases. We assembled clinical and genetic information for never-smoker patients with NSCLC accrued in Japan, Korea, Singapore, and the United States. To determine an association between cumulative ETS and activating EGFR mutations or ALK rearrangements, the Mantel extension test was used. Multivariate analysis on activating EGFR and ALK gene rearrangements was performed using the generalized linear mixed model with nations as a random effect. From July 2007 to December 2012, 498 never-smokers with pathologically proven NSCLC were registered and tested for the association between ETS and EGFR and ALK status. EGFR mutations were more frequent in the ever-ETS cohort (58.4%) compared with the never-ETS cohort (39.6%), and the incidence of EGFR mutations was significantly associated with the increment of cumulative ETS (cETS) in female never-smokers (P = .033), whereas the incidence of ALK rearrangements was not significantly different between the ever-ETS and never-ETS cohorts. Odds ratio for EGFR mutations for each 10-year increment in cETS was 1.091 and 0.89 for female and male never-smokers (P = .031 and P = .263, respectively). Increased ETS exposure was closely associated with EGFR mutations in female never-smokers with NSCLC in the expanded multinational cohort. However, the association of ETS and ALK rearrangements in never-smokers with NSCLC was not significant. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Neutron activation determination of impurities in molybdenum

    International Nuclear Information System (INIS)

    Usmanova, M.M.; Mukhamedshina, N.M.; Obraztsova, T.V.; Saidakhmedov, K.Kh.

    1984-01-01

    Instrumental neutron-activation techniques of impurity element determination in molybdenum and MoO 3 (solid and powdered samples) have been developed. When determining impurities of Na, K, Mn, Cu, W, Re molybdenum has been irradiated by thermal neutrons in reactor for 20 min, the sample mass constituted 200-300 mg, sample cooling time after irradiation - 2.5-3.5 h. It is shown that in the process of Cr, Fe, Co, Zn determination the samples should be irradiated with thermal neutrons, and in the process of Sb, Ta and Ni determination - with resonance and fast neutrons. Simultaneous determination of the elements during irradiation with neutrons with reactor spectrum is possible. When determining P and S the samples are irradiated with thermal and epithermal neutrons and β-activity of samples and comparison samples are measured using β-spectrometer with anthracene crystal. The techniques developed permit to determine impurities in Mo with a relative standard deviation 0.07-0.15 and lower boundaries of contents determined - 10 -4 - 10 -7 %

  5. Construction of a high-EGFR expression cell line and its biological ...

    African Journals Online (AJOL)

    USER

    2010-07-26

    Jul 26, 2010 ... activator of transcription (STAT) pathways, which regulate cell transformation ... Construction of a EGFR eukaryotic expression vector. The plasmid .... was 4-5 times greater in the Aft-HEK293 cells following transfection. EGFR ...

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

    International Nuclear Information System (INIS)

    Sobhakumari, Arya; Schickling, Brandon M.; Love-Homan, Laurie; Raeburn, Ayanna; Fletcher, Elise V.M.; Case, Adam J.; Domann, Frederick E.; Miller, Francis J.

    2013-01-01

    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

  7. 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.

  8. Benzo[g]quinazolin-based scaffold derivatives as dual EGFR/HER2 inhibitors.

    Science.gov (United States)

    Ghorab, Mostafa M; Alsaid, Mansour S; Soliman, Aiten M; Al-Mishari, Abdullah A

    2018-12-01

    Targeting EGFR has proven to be beneficial in the treatment of several types of solid tumours. So, a series of novel 2-(4-oxo-3-(4-sulfamoylphenyl)-3,4-dihydrobenzo[g]quinazolin-2-ylthio)-N-substituted acetamide 5-19 were synthesised from the starting material 4-(2-mercapto-4-oxobenzo[g]quinazolin-3(4H)-yl) benzenesulfonamide 4, to be evaluated as dual EGFR/HER2 inhibitors. The target compounds 5-19, were screened for their cytotoxic activity against A549 lung cancer cell line. The percentage inhibition of EGFR enzyme was measured and compared with erlotinib as the reference drug. Compounds 6, 8, 10, and 16 showed excellent EGFR inhibitory activity and were further selected for screening as dual EGFR/HER2 inhibitors. The four selected compounds showed IC 50 ranging from 0.009 to 0.026 µM for EGFR and 0.021 to 0.069 µM for the HER2 enzyme. Compound 8 was found to be the most potent in this study with IC 50 0.009 and 0.021 µM for EGFR and HER2, respectively.

  9. Cationic Polyamidoamine Dendrimers as Modulators of EGFR Signaling In Vitro and In Vivo.

    Directory of Open Access Journals (Sweden)

    Saghir Akhtar

    Full Text Available Cationic polyamidoamine (PAMAM dendrimers are branch-like spherical polymers being investigated for a variety of applications in nanomedicine including nucleic acid drug delivery. Emerging evidence suggests they exhibit intrinsic biological and toxicological effects but little is known of their interactions with signal transduction pathways. We previously showed that the activated (fragmented generation (G 6 PAMAM dendrimer, Superfect (SF, stimulated epidermal growth factor receptor (EGFR tyrosine kinase signaling-an important signaling cascade that regulates cell growth, survival and apoptosis- in cultured human embryonic kidney (HEK 293 cells. Here, we firstly studied the in vitro effects of Polyfect (PF, a non-activated (intact G6 PAMAM dendrimer, on EGFR tyrosine kinase signaling via extracellular-regulated kinase 1/2 (ERK1/2 and p38 mitogen-activated protein kinase (MAPK in cultured HEK 293 cells and then compared the in vivo effects of a single administration (10mg/kg i.p of PF or SF on EGFR signaling in the kidneys of normal and diabetic male Wistar rats. Polyfect exhibited a dose- and time-dependent inhibition of EGFR, ERK1/2 and p38 MAPK phosphorylation in HEK-293 cells similar to AG1478, a selective EGFR inhibitor. Administration of dendrimers to non-diabetic or diabetic animals for 24h showed that PF inhibited whereas SF stimulated EGFR phosphorylation in the kidneys of both sets of animals. PF-mediated inhibition of EGFR phosphorylation as well as SF or PF-mediated apoptosis in HEK 293 cells could be significantly reversed by co-treatment with antioxidants such as tempol implying that both these effects involved an oxidative stress-dependent mechanism. These results show for the first time that SF and PF PAMAM dendrimers can differentially modulate the important EGFR signal transduction pathway in vivo and may represent a novel class of EGFR modulators. These findings could have important clinical implications for the use of PAMAM

  10. 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......-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...

  11. Prognostic value of plasma EGFR ctDNA in NSCLC patients treated with EGFR-TKIs.

    Directory of Open Access Journals (Sweden)

    Chengjuan Zhang

    Full Text Available Epidermal growth factor receptor (EGFR specific mutations have been known to improve survival of patients with non-small-cell lung carcinoma (NSCLC. However, whether there are any changes of EGFR mutations after targeted therapy and its clinical significance is unclear. This study was to identify the status of EGFR mutations after targeted therapy and predict the prognostic significance for NSCLC patients.A total of forty-five (45 NSCLC patients who received EGFR-TKI therapy were enrolled. We identified the changes of EGFR mutations in plasma ctDNA by Amplification Refractory Mutation System (ARMS PCR technology.In the 45 cases of NSCLC with EGFR mutations, the EGFR mutation status changed in 26 cases, in which, 12 cases (26.7% from positive to negative, and 14 cases (31.1% from T790M mutation negative to positive after TKI targeted therapy. The T790M occurance group had a shorter Progression -Free-Survival (PFS than the groups of EGFR mutation undetected and EGFR mutation turned out to have no change after EGFR-TKI therapy (p < 0.05.According to this study, it's necessary to closely monitor EGFR mutations during follow-up to predict the prognosis of NSCLC patients who are to receive the TKI targeted therapy.

  12. EGFR and its mutant EGFRvIII as modulators of tumor cell radiosensitivity

    International Nuclear Information System (INIS)

    Lammering, G.; Hewit, T.H.; Contessa, J.N.; Hawkins, W.; Lin, P.S.; Valerie, K.; Mikkelsen, R.; Dent, P.; Schmidt-Ullrich, R.K.

    2001-01-01

    Purpose: Exposure of human carcinoma and malignant glioma cells to ionizing radiation (IR)activates EGFR,which as a consequence mediates a cytoprotective response. We have demonstrated that expression of a dominant negative mutant, EGFR-CD533 disrupts this cytoprotective response, resulting in significant radiosensitization. During studies of in vivo radiosensitization with intratumoral delivery of the Adenovirus (Ad) vector, Ad-EGFR-CD533, it became apparent that xenografts from human carcinoma and malignant glioma cells invariably expressed the constitutively active EGFR mutant, EGFRvIII. This mutant EGFRvIII is frequently found in vivo in glioblastoma, breast, prostate, lung and ovarian carcinoma, but does not appear to be expressed in tumor cells under in vitro conditions. The functional consequences of EGFRvIII expression on tumor cell radiation responses are currently unknown. We have therefore investigated in a transient transfection cell system the responses of EGFRvIII and downstream signal transduction pathways to IR. In addition, the capacity of EGFR-CD533 to disrupt the function of EGFRvIII was tested. Materials and Methods: The MDA-MB-231, U-87 MG and U-373 MG cell lines were established as tumors and then intratumorally transduced with Ad-EGFR-CD533 or Ad-LacZ (control vector). The transduction efficiency was > 40% in MDA-MB-231 tumors and reached > 70% in the glioma xenografts. Radiosensitivity was measured by ex vivo colony formation and growth delay assays. The functional consequences of EGFRvIII expression on cellular IR responses were studied in transiently transfected Chinese hamster ovary (CHO) cells because tumor cells do not express EGFRvIII in vitro. Transfection with null vectors and vectors encoding either EGFRvIII or EGFR were performed and similar protein expression levels were verified by Western blot analyses. Results: The radiosensitivity of Ad-EGFR-CD533 transduced tumors was significantly increased compared with Ad-LacZ transduced

  13. In vivo imaging of the dynamics of different variants of EGFR in glioblastomas.

    Science.gov (United States)

    Shah, Khalid

    2011-01-01

    A number of altered pathways in cancer cells depend on growth factor receptors. The amplification/alteration of the epidermal growth factor receptor (EGFR) has been shown to play a significant role in enhancing tumor burden in a number of tumors, including malignant glioblastomas (GBM). To dissect the role of EGFR expression in tumor progression in mouse models of cancer and ultimately evaluate targeted therapies, it is necessary to visualize the dynamics of EGFR in real time in vivo. Non-invasive imaging based on quantitative and qualitative changes in light emission by fluorescent and bioluminescent markers offers a huge potential to facilitate drug development. Multiple approaches could be used to follow a molecular target or pathway with the fusion of a bioluminescent-fluorescent marker. This unit describes a protocol for simultaneously imaging EGFR activity and progression of GBM in a mouse model. Human glioma cells transduced with lentiviral vectors bearing different combinations of fluorescent and bioluminescent proteins either fused to EGFR or expressed alone can be grown as monolayers and maintained over several passages. The unit begins with a method for transducing glioma cells with lentiviral vectors for stable expression of these fluorescent and bioluminescent markers in vitro, followed by transplantation of engineered glioma cells in mice, and, finally, sequential bioluminescent imaging of EGFR expression and GBM progression in mice. The protocol details characterization of engineered glioma cells in culture, surgical preparation, craniotomy, cell implantation, animal recovery, and imaging procedures to study kinetics of EGFR expression and GBM progression.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Consensus for EGFR mutation testing in non-small cell lung cancer: results from a European workshop

    DEFF Research Database (Denmark)

    Pirker, Robert; Herth, Felix J F; Kerr, Keith M

    2010-01-01

    Activating somatic mutations of the tyrosine kinase domain of epidermal growth factor receptor (EGFR) have recently been characterized in a subset of patients with advanced non-small cell lung cancer (NSCLC). Patients harboring these mutations in their tumors show excellent response to EGFR tyros...

  17. 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

    The epidermal growth factor receptor (EGFR) is an important regulator of normal growth and differentiation, and it is involved in the pathogenesis of many cancers. Endocytic downregulation is central in terminating EGFR signaling after ligand stimulation. It has been shown that p38 MAPK activation...

  18. Evaluation of radiolabeled ML04, a putative irreversible inhibitor of epidermal growth factor receptor, as a bioprobe for PET imaging of EGFR-overexpressing tumors

    International Nuclear Information System (INIS)

    Abourbeh, Galith; Dissoki, Samar; Jacobson, Orit; Litchi, Amir; Daniel, Revital Ben; Laki, Desirediu; Levitzki, Alexander; Mishani, Eyal

    2007-01-01

    Overexpression of epidermal growth factor receptor (EGFR) has been implicated in tumor development and malignancy. Evaluating the degree of EGFR expression in tumors could aid in identifying patients for EGFR-targeted therapies and in monitoring treatment. Nevertheless, no currently available assay can reliably quantify receptor content in tumors. Radiolabeled inhibitors of EGFR-TK could be developed as bioprobes for positron emission tomography imaging. Such imaging agents would not only provide a noninvasive quantitative measurement of EGFR content in tumors but also serve as radionuclide carriers for targeted radiotherapy. The potency, reversibility, selectivity and specific binding characteristics of ML04, an alleged irreversible inhibitor of EGFR, were established in vitro. The distribution of the F-18-labeled compound and the extent of EGFR-specific tumor uptake were evaluated in tumor-bearing mice. ML04 demonstrated potent, irreversible and selective inhibition of EGFR, combined with specific binding to the receptor in intact cells. In vivo distribution of the radiolabeled compound revealed tumor/blood and tumor/muscle activity uptake ratios of about 7 and 5, respectively, 3 h following administration of a radiotracer. Nevertheless, only minor EGFR-specific uptake of the compound was detected in these studies, using either EGFR-negative tumors or blocking studies as controls. To improve the in vivo performance of ML04, administration via prolonged intravenous infusion is proposed. Detailed pharmacokinetic characterization of this bioprobe could assist in the development of a kinetic model that would afford accurate measurement of EGFR content in tumors

  19. Genomic Profiling on an Unselected Solid Tumor Population Reveals a Highly Mutated Wnt/β-Catenin Pathway Associated with Oncogenic EGFR Mutations

    Directory of Open Access Journals (Sweden)

    Jingrui Jiang

    2018-04-01

    Full Text Available Oncogenic epidermal growth factor receptors (EGFRs can recruit key effectors in diverse cellular processes to propagate oncogenic signals. Targeted and combinational therapeutic strategies have been successfully applied for treating EGFR-driven cancers. However, a main challenge in EGFR therapies is drug resistance due to mutations, oncogenic shift, alternative signaling, and other potential mechanisms. To further understand the genetic alterations associated with oncogenic EGFRs and to provide further insight into optimal and personalized therapeutic strategies, we applied a proprietary comprehensive next-generation sequencing (NGS-based assay of 435 genes to systematically study the genomic profiles of 1565 unselected solid cancer patient samples. We found that activating EGFR mutations were predominantly detected in lung cancer, particularly in non-small cell lung cancer (NSCLC. The mutational landscape of EGFR-driven tumors covered most key signaling pathways and biological processes. Strikingly, the Wnt/β-catenin pathway was highly mutated (48 variants detected in 46% of the EGFR-driven tumors, and its variant number topped that in the TP53/apoptosis and PI3K-AKT-mTOR pathways. Furthermore, an analysis of mutation distribution revealed a differential association pattern of gene mutations between EGFR exon 19del and EGFR L858R. Our results confirm the aggressive nature of the oncogenic EGFR-driven tumors and reassure that a combinational strategy should have advantages over an EGFR-targeted monotherapy and holds great promise for overcoming drug resistance.

  20. Activation determination of copper in food

    International Nuclear Information System (INIS)

    Jiranek, V.; Bludovsky, R.

    1982-01-01

    Neutron activation analysis was used for determining copper content in food. Analyzed were dried milk, flour, coffee, tea, husked rice, and liver. Bowen's kale powder with a guaranteed copper content of 3.6 to 6.5 ppm was used as a reference biological material. The instruments, chemicals and solutions used are reported. The method is described of copper separation with α-benzoinoxime and pyridine as is the procedure for the destructive activation analysis of samples. The copper concentrations in the foods under analysis were found to range within usual limits. The copper concentration determined in the reference material agreed with the measured value. The analysis confirms that the method yields reliable results. (J.B.)

  1. Identification of potent EGFR inhibitors from TCM Database@Taiwan.

    Directory of Open Access Journals (Sweden)

    Shun-Chieh Yang

    2011-10-01

    Full Text Available Overexpression of epidermal growth factor receptor (EGFR has been associated with cancer. Targeted inhibition of the EGFR pathway has been shown to limit proliferation of cancerous cells. Hence, we employed Traditional Chinese Medicine Database (TCM Database@Taiwan (http://tcm.cmu.edu.tw to identify potential EGFR inhibitor. Multiple Linear Regression (MLR, Support Vector Machine (SVM, Comparative Molecular Field Analysis (CoMFA, and Comparative Molecular Similarities Indices Analysis (CoMSIA models were generated using a training set of EGFR ligands of known inhibitory activities. The top four TCM candidates based on DockScore were 2-O-caffeoyl tartaric acid, Emitine, Rosmaricine, and 2-O-feruloyl tartaric acid, and all had higher binding affinities than the control Iressa®. The TCM candidates had interactions with Asp855, Lys716, and Lys728, all which are residues of the protein kinase binding site. Validated MLR (r² = 0.7858 and SVM (r² = 0.8754 models predicted good bioactivity for the TCM candidates. In addition, the TCM candidates contoured well to the 3D-Quantitative Structure-Activity Relationship (3D-QSAR map derived from the CoMFA (q² = 0.721, r² = 0.986 and CoMSIA (q² = 0.662, r² = 0.988 models. The steric field, hydrophobic field, and H-bond of the 3D-QSAR map were well matched by each TCM candidate. Molecular docking indicated that all TCM candidates formed H-bonds within the EGFR protein kinase domain. Based on the different structures, H-bonds were formed at either Asp855 or Lys716/Lys728. The compounds remained stable throughout molecular dynamics (MD simulation. Based on the results of this study, 2-O-caffeoyl tartaric acid, Emitine, Rosmaricine, and 2-O-feruloyl tartaric acid are suggested to be potential EGFR inhibitors.

  2. Determination of PAF-2-acylhydrolase activity

    International Nuclear Information System (INIS)

    Pickard, R.N.; Ludwig, J.C.

    1986-01-01

    A simple and rapid procedure has been developed to determine the PAF-2-acylhydrolase activity in various biological fluids. The assay was based upon the following biophysical properties of PAF (1-O-hexadecyl-2- 3 H-acetyl-sn-glycero-3-phosphocholine, 10 Ci/mMole). In aqueous solution PAF is not soluble below its critical micellar concentration (1.1 μM) unless albumin (2.5 mg/ml) is present which binds and stabilizes PAF in solution. However, upon precipitation of the albumin with trichloroacetic acid (TCA), 100% of the PAF also co-precipitates. Thus, in a reaction mixture to assess PAF-2-acylhydrolase activity conducted in the presence of albumin, termination of the reaction by the addition of TCA (10% final concentration) precipitates all residual PAF and also inactivates all PAF-2-acylhydrolase activity. Under these conditions 100% of the released 3 H-acetate is recovered in the supernatant after centrifugation, 10,000 x g for 60 sec. Therefore, determination of released 3 H-acetate provides a highly accurate and reproducible measurement of both substrate (PAF) and product ( 3 H-acetate) concentrations. Kinetic studies assessing the PAF-2-acylhydrolase in human serum diluted in Hank's balance salt solution containing 2.5 mg/ml human albumin, pH 7.20 yielded an apparent Km = 5 nM

  3. Navigating into the binding pockets of the HER family protein kinases: discovery of novel EGFR inhibitor as antitumor agent.

    Science.gov (United States)

    Liu, Wei; Ning, Jin-Feng; Meng, Qing-Wei; Hu, Jing; Zhao, Yan-Bin; Liu, Chao; Cai, Li

    2015-01-01

    The epidermal growth factor receptor (EGFR) family has been validated as a successful antitumor drug target for decades. Known EGFR inhibitors were exposed to distinct drug resistance against the various EGFR mutants within non-small-cell lung cancer (NSCLC), particularly the T790M mutation. Although so far a number of studies have been reported on the development of third-generation EGFR inhibitors for overcoming the resistance issue, the design procedure largely depends on the intuition of medicinal chemists. Here we retrospectively make a detailed analysis of the 42 EGFR family protein crystal complexes deposited in the Protein Data Bank (PDB). Based on the analysis of inhibitor binding modes in the kinase catalytic cleft, we identified a potent EGFR inhibitor (compound A-10) against drug-resistant EGFR through fragment-based drug design. This compound showed at least 30-fold more potency against EGFR T790M than the two control molecules erlotinib and gefitinib in vitro. Moreover, it could exhibit potent HER2 inhibitory activities as well as tumor growth inhibitory activity. Molecular docking studies revealed a structural basis for the increased potency and mutant selectivity of this compound. Compound A-10 may be selected as a promising candidate in further preclinical studies. In addition, our findings could provide a powerful strategy to identify novel selective kinase inhibitors on the basis of detailed kinase-ligand interaction space in the PDB.

  4. Epidermal growth factor receptor (EGFR) mutations and expression in squamous cell carcinoma of the esophagus in central Asia

    International Nuclear Information System (INIS)

    Abedi-Ardekani, Behnoush; Malekzadeh, Reza; Hainaut, Pierre; Dar, Nazir Ahmad; Mir, Mohammad Muzaffar; Zargar, Showkat Ahmad; Lone, M Muqbool; Martel-Planche, Ghyslaine; Villar, Stéphanie; Mounawar, Mounia; Saidi, Farrokh

    2012-01-01

    Esophageal squamous cell carcinoma (ESCC) shows geographic variations in incidence, with high incidences (>50/10 5 person-years) in central Asia, including North Eastern Iran (Golestan) and Northern India (Kashmir). In contrast to Western countries, smoking does not appear to be a significant risk factor for ESCC in central Asia. In lung adenocarcinoma, activating mutations in the gene encoding epidermal growth factor receptor (EGFR) are frequent in tumors of never smokers of Asian origin, predicting therapeutic sensitivity to Egfr-targeting drugs. In this study 152 cases of histologically confirmed ESCC from Iran (Tehran and Golestan Province) and North India (Kashmir Valley) have been analyzed for EGFR mutation by direct sequencing of exons 18–21. Egfr protein expression was evaluated by immunohistochemistry in 34 samples from Tehran and HER2 mutations were analyzed in 54 cases from Kashmir. A total of 14 (9.2%) EGFR variations were detected, including seven variations in exons. Among those, four (2.6%) were already documented in lung cancers, two were reported as polymorphisms and one was a potentially new activating mutation. All but one variation in introns were previously identified as polymorphisms. Over-expression of Egfr was detected in 22/34 (65%) of tested cases whereas no HER2 mutation was found in 54 cases from Kashmir. Overall, EGFR mutations appear to be a rare event in ESCC in high incidence areas of central Asia, although a very small proportion of cases may harbor mutations predicting sensitivity to anti-Egfr drugs

  5. Determination of Russian innovative activity tendencies

    Directory of Open Access Journals (Sweden)

    Marina A. Motova

    2016-01-01

    Higher School of Economics and «The Russian Statistical Year-Book» of Rosstat.Data on a condition of the innovative sphere in Russia, and, also data on profitability of financial investments cover the industrial production (the extracting and processing productions and the enterprises on production and electric power, gas and water distribution, and also some industries of the service sector. The analysis covers the data for the period of 2005-2014. It covers the data on the innovation-active organizations, engaged in technological innovations by main types of economic and innovative activity. In total the given results, from our point of view, can become a basis for the choice of the directions of investment activity.Development of forecasts of the main indicators of the innovative sphere shall become the perspective direction of research continuation. The received forecasts will be the basis for the cluster analysis procedure for the purpose of prospects’ determination for the development of investment activity in innovation-active sectors of economy

  6. Assessment of Epidermal Growth Factor Receptor (EGFR expression in human meningioma

    Directory of Open Access Journals (Sweden)

    Perry Arie

    2010-05-01

    Full Text Available Abstract Purpose This study explores whether meningioma expresses epidermal growth factor receptor (EGFR and determines if there is a correlation between the WHO grade of this tumor and the degree of EGFR expression. Methods Following institutional review board approval, 113 meningioma specimens from 89 patients were chosen. Of these, 85 were used for final analysis. After a blinded review, immunohistochemical stains for EGFR were performed. Staining intensity (SI was scored on a scale 0-3 (from no staining to strong staining. Staining percentage of immunoreactive cells (SP was scored 1-5 (from the least to the maximum percent of the specimen staining. Immunohistochemical score (IHS was calculated as the product of SI and SP. Results Eighty-five samples of meningioma were classified in accordance with World Health Organization (WHO criteria: benign 57/85 (67%, atypical 23/85 (27%, and malignant 5/85 (6%. The majority of samples demonstrated a moderate SI for EGFR. IHS for EGFR demonstrated a significant association between SI and histopathologic subtype. Also, there was a correlation between the SP and histopathologic subtype (p = 0.029. A significant association was determined when the benign and the atypical samples were compared to the malignant with respect to the SP (p = 0.009. While there was a range of the IHS for the benign and the atypical histologic subtypes, malignant tumors exhibited the lowest score and were statistically different from the benign and the atypical specimens (p Conclusions To our knowledge, this represents the largest series of meningioma samples analyzed for EGFR expression reported in the literature. EGFR expression is greatest in benign meningiomas and may serve a potential target for therapeutic intervention with selective EGFR inhibitors.

  7. Tumor-targeted Nanobullets: Anti-EGFR nanobody-liposomes loaded with anti-IGF-1R kinase inhibitor for cancer treatment.

    Science.gov (United States)

    van der Meel, Roy; Oliveira, Sabrina; Altintas, Isil; Haselberg, Rob; van der Veeken, Joris; Roovers, Rob C; van Bergen en Henegouwen, Paul M P; Storm, Gert; Hennink, Wim E; Schiffelers, Raymond M; Kok, Robbert J

    2012-04-30

    The epidermal growth factor receptor (EGFR) is a validated target for anti-cancer therapy and several EGFR inhibitors are used in the clinic. Over the years, an increasing number of studies have reported on the crosstalk between EGFR and other receptors that can contribute to accelerated cancer development or even acquisition of resistance to anti-EGFR therapies. Combined targeting of EGFR and insulin-like growth factor 1 receptor (IGF-1R) is a rational strategy to potentiate anti-cancer treatment and possibly retard resistance development. In the present study, we have pursued this by encapsulating the kinase inhibitor AG538 in anti-EGFR nanobody-liposomes. The thus developed dual-active nanobody-liposomes associated with EGFR-(over)expressing cells in an EGFR-specific manner and blocked both EGFR and IGF-1R activation, due to the presence of the EGFR-blocking nanobody EGa1 and the anti-IGF-1R kinase inhibitor AG538 respectively. AG538-loaded nanobody-liposomes induced a strong inhibition of tumor cell proliferation even upon short-term exposure followed by a drug-free wash-out period. Therefore, AG538-loaded nanobody-liposomes are a promising anti-cancer formulation due to efficient intracellular delivery of AG538 in combination with antagonistic and downregulating properties of the EGa1 nanobody-liposomes. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Gallic acid abolishes the EGFR/Src/Akt/Erk-mediated expression of matrix metalloproteinase-9 in MCF-7 breast cancer cells.

    Science.gov (United States)

    Chen, Ying-Jung; Lin, Ku-Nan; Jhang, Li-Mei; Huang, Chia-Hui; Lee, Yuan-Chin; Chang, Long-Sen

    2016-05-25

    Several studies have revealed that natural compounds are valuable resources to develop novel agents against dysregulation of the EGF/EGFR-mediated matrix metalloproteinase-9 (MMP-9) expression in cancer cells. In view of the findings that EGF/EGFR-mediated MMP-9 expression is closely related to invasion and metastasis of breast cancer. To determine the beneficial effects of gallic acid on the suppression of breast cancer metastasis, we explored the effect of gallic acid on MMP-9 expression in EGF-treated MCF-7 breast cancer cells. Treatment with EGF up-regulated MMP-9 mRNA and protein levels in MCF-7 cells. EGF treatment induced phosphorylation of EGFR and elicited Src activation, subsequently promoting Akt/NFκB (p65) and ERK/c-Jun phosphorylation in MCF-7 cells. Activation of Akt/p65 and ERK/c-Jun was responsible for the MMP-9 up-regulation in EGF-treated cells. Gallic acid repressed the EGF-induced activation of EGFR and Src; furthermore, inactivation of Akt/p65 and ERK/c-Jun was a result of the inhibitory effect of gallic acid on the EGF-induced MMP-9 up-regulation. Over-expression of constitutively active Akt and MEK1 or over-expression of constitutively active Src eradicated the inhibitory effect of gallic acid on the EGF-induced MMP-9 up-regulation. A chromosome conformation capture assay showed that EGF induced a chromosomal loop formation in the MMP-9 promoter via NFκB/p65 and AP-1/c-Jun activation. Treatment with gallic acid, EGFR inhibitor, or Src inhibitor reduced DNA looping. Taken together, our data suggest that gallic acid inhibits the activation of EGFR/Src-mediated Akt and ERK, leading to reduced levels of p65/c-Jun-mediated DNA looping and thus inhibiting MMP-9 expression in EGF-treated MCF-7 cells. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Targeting EGFR induced oxidative stress by PARP1 inhibition in glioblastoma therapy.

    Science.gov (United States)

    Nitta, Masayuki; Kozono, David; Kennedy, Richard; Stommel, Jayne; Ng, Kimberly; Zinn, Pascal O; Kushwaha, Deepa; Kesari, Santosh; Inda, Maria-del-Mar; Wykosky, Jill; Furnari, Frank; Hoadley, Katherine A; Chin, Lynda; DePinho, Ronald A; Cavenee, Webster K; D'Andrea, Alan; Chen, Clark C

    2010-05-24

    Despite the critical role of Epidermal Growth Factor Receptor (EGFR) in glioblastoma pathogenesis, EGFR targeted therapies have achieved limited clinical efficacy. Here we propose an alternate therapeutic strategy based on the conceptual framework of non-oncogene addiction. A directed RNAi screen revealed that glioblastoma cells over-expressing EGFRvIII, an oncogenic variant of EGFR, become hyper-dependent on a variety of DNA repair genes. Among these, there was an enrichment of Base Excision Repair (BER) genes required for the repair of Reactive Oxygen Species (ROS)-induced DNA damage, including poly-ADP ribose polymerase 1 (PARP1). Subsequent studies revealed that EGFRvIII over-expression in glioblastoma cells caused increased levels of ROS, DNA strand break accumulation, and genome instability. In a panel of primary glioblastoma lines, sensitivity to PARP1 inhibition correlated with the levels of EGFR activation and oxidative stress. Gene expression analysis indicated that reduced expression of BER genes in glioblastomas with high EGFR expression correlated with improved patient survival. These observations suggest that oxidative stress secondary to EGFR hyper-activation necessitates increased cellular reliance on PARP1 mediated BER, and offer critical insights into clinical trial design.

  10. Targeting EGFR induced oxidative stress by PARP1 inhibition in glioblastoma therapy.

    Directory of Open Access Journals (Sweden)

    Masayuki Nitta

    Full Text Available Despite the critical role of Epidermal Growth Factor Receptor (EGFR in glioblastoma pathogenesis, EGFR targeted therapies have achieved limited clinical efficacy. Here we propose an alternate therapeutic strategy based on the conceptual framework of non-oncogene addiction. A directed RNAi screen revealed that glioblastoma cells over-expressing EGFRvIII, an oncogenic variant of EGFR, become hyper-dependent on a variety of DNA repair genes. Among these, there was an enrichment of Base Excision Repair (BER genes required for the repair of Reactive Oxygen Species (ROS-induced DNA damage, including poly-ADP ribose polymerase 1 (PARP1. Subsequent studies revealed that EGFRvIII over-expression in glioblastoma cells caused increased levels of ROS, DNA strand break accumulation, and genome instability. In a panel of primary glioblastoma lines, sensitivity to PARP1 inhibition correlated with the levels of EGFR activation and oxidative stress. Gene expression analysis indicated that reduced expression of BER genes in glioblastomas with high EGFR expression correlated with improved patient survival. These observations suggest that oxidative stress secondary to EGFR hyper-activation necessitates increased cellular reliance on PARP1 mediated BER, and offer critical insights into clinical trial design.

  11. Therapeutic value of EGFR inhibition in CRC and NSCLC: 15 years of clinical evidence.

    Science.gov (United States)

    Troiani, Teresa; Napolitano, Stefania; Della Corte, Carminia Maria; Martini, Giulia; Martinelli, Erika; Morgillo, Floriana; Ciardiello, Fortunato

    2016-01-01

    Epidermal growth factor receptor (EGFR) plays a key role in tumour evolution, proliferation and immune evasion, and is one of the most important targets for biological therapy, especially for non-small-cell lung cancer (NSCLC) and colorectal cancer (CRC). In the past 15 years, several EGFR antagonists have been approved for the treatment of NSCLC and metastatic CRC (mCRC). To optimise the use of anti-EGFR agents in clinical practice, various clinical and molecular biomarkers have been investigated, thus moving their indication from unselected to selected populations. Nowadays, anti-EGFR drugs represent a gold-standard therapy for metastatic NSCLC harbouring EGFR activating mutation and for RAS wild-type mCRC. Their clinical efficacy is limited by the presence of intrinsic resistance or the onset of acquired resistance. In this review, we provide an overview of the antitumour activity of EGFR inhibitors in NSCLC and CRC and of mechanisms of resistance, focusing on the development of a personalised approach through 15 years of preclinical and clinical research.

  12. Structural insights into drug development strategy targeting EGFR T790M/C797S.

    Science.gov (United States)

    Zhu, Su-Jie; Zhao, Peng; Yang, Jiao; Ma, Rui; Yan, Xiao-E; Yang, Sheng-Yong; Yang, Jing-Wen; Yun, Cai-Hong

    2018-03-02

    Treatment of non-small-cell lung cancers (NSCLCs) harboring primary EGFR oncogenic mutations such as L858R and exon 19 deletion delE746_A750 (Del-19) using gefitinib/erlotinib ultimately fails due to the emergence of T790M mutation. Though WZ4002/CO-1686/AZD9291 are effective in overcoming EGFR T790M by targeting Cys797 via covalent bonding, their efficacy is again limited due to the emergence of C797S mutation. New agents effectively inhibiting EGFR T790M without covalent linkage through Cys 797 may solve this problem. We presented here crystal structures of EGFR activating/drug-resistant mutants in complex with a panel of reversible inhibitors along with mutagenesis and enzyme kinetic data. These data revealed a previously un-described hydrophobic clamp structure in the EGFR kinase which may be exploited to facilitate development of next generation drugs targeting EGFR T790M with or without concomitant C797S. Interestingly, mutations in the hydrophobic clamp that hinder drug binding often also weaken ATP binding and/or abolish kinase activity, thus do not readily result in resistance to the drugs.

  13. Levels of active tyrosine kinase receptor determine the tumor response to Zalypsis

    International Nuclear Information System (INIS)

    Moneo, Victoria; Serelde, Beatriz G; Blanco-Aparicio, Carmen; Diaz-Uriarte, Ramon; Avilés, Pablo; Santamaría, Gemma; Tercero, Juan C; Cuevas, Carmen; Carnero, Amancio

    2014-01-01

    Zalypsis® is a marine compound in phase II clinical trials for multiple myeloma, cervical and endometrial cancer, and Ewing’s sarcoma. However, the determinants of the response to Zalypsis are not well known. The identification of biomarkers for Zalypsis activity would also contribute to broaden the spectrum of tumors by selecting those patients more likely to respond to this therapy. Using in vitro drug sensitivity data coupled with a set of molecular data from a panel of sarcoma cell lines, we developed molecular signatures that predict sensitivity to Zalypsis. We verified these results in culture and in vivo xenograft studies. Zalypsis resistance was dependent on the expression levels of PDGFRα or constitutive phosphorylation of c-Kit, indicating that the activation of tyrosine kinase receptors (TKRs) may determine resistance to Zalypsis. To validate our observation, we measured the levels of total and active (phosphorylated) forms of the RTKs PDGFRα/β, c-Kit, and EGFR in a new panel of diverse solid tumor cell lines and found that the IC50 to the drug correlated with RTK activation in this new panel. We further tested our predictions about Zalypsis determinants for response in vivo in xenograft models. All cells lines expressing low levels of RTK signaling were sensitive to Zalypsis in vivo, whereas all cell lines except two with high levels of RTK signaling were resistant to the drug. RTK activation might provide important signals to overcome the cytotoxicity of Zalypsis and should be taken into consideration in current and future clinical trials

  14. Molecular Epidemiology of EGFR Mutations in Asian Patients with Advanced Non-Small-Cell Lung Cancer of Adenocarcinoma Histology – Mainland China Subset Analysis of the PIONEER study

    Science.gov (United States)

    Shi, Yuankai; Li, Junling; Zhang, Shucai; Wang, Mengzhao; Yang, Shujun; Li, Ning; Wu, Gang; Liu, Wei; Liao, Guoqing; Cai, Kaican; Chen, Liang’an; Zheng, Meizhen; Yu, Ping; Wang, Xiuwen; Liu, Yunpeng; Guo, Qisen; Nie, Ligong; Liu, Jiwei; Han, Xiaohong

    2015-01-01

    Epidermal growth factor receptor (EGFR) mutations are the strongest response predictors to EGFR tyrosine kinase inhibitors (TKI) therapy, but knowledge of the EGFR mutation frequency on lung adenocarcinoma is still limited to retrospective studies. The PIONEER study (NCT01185314) is a prospective molecular epidemiology study in Asian patients with newly diagnosed advanced lung adenocarcinoma, aiming to prospectively analyze EGFR mutation status in IIIB/IV treatment-naïve lung adenocarcinomas in Asia. We report the mainland China subset results. Eligible patients (≥20 yrs old, IIIB/IV adenocarcinoma and treatment-naïve) were registered in 17 hospitals in mainland China. EGFR was tested for mutations by amplification refractory mutation system using biopsy samples. Demographic and clinical characteristics were collected for subgroup analyses. A total of 747 patients were registered. Successful EGFR mutation analysis was performed in 741, with an overall mutation rate of 50.2%. The EGFR active mutation rate is 48.0% (with 1.3% of combined active and resistance mutations). Tobacco use (>30 pack-year vs. 0–10 pack-year, OR 0.27, 95%CI: 0.17–0.42) and regional lymph nodes involvement (N3 vs. N0, OR 0.47, 95%CI: 0.29–0.76) were independent predictors of EGFR mutation in multivariate analysis. However, even in regular smokers, the EGFR mutation frequency was 35.3%. The EGFR mutation frequency was similar between diverse biopsy sites and techniques. The overall EGFR mutation frequency of the mainland China subset was 50.2%, independently associated with the intensity of tobacco use and regional lymph nodes involvement. The relatively high frequency of EGFR mutations in the mainland China subset suggest that any effort to obtain tissue sample for EGFR mutation testing should be encouraged. PMID:26599344

  15. Sequential treatment of icotinib after first-line pemetrexed in advanced lung adenocarcinoma with unknown EGFR gene status.

    Science.gov (United States)

    Zheng, Yulong; Fang, Weijia; Deng, Jing; Zhao, Peng; Xu, Nong; Zhou, Jianying

    2014-07-01

    In non-small cell lung cancer (NSCLC), the well-developed epidermal growth factor receptor (EGFR) is an important therapeutic target. EGFR activating gene mutations have been proved strongly predictive of response to EGFR-tyrosine kinase inhibitors (TKI) in NSCLC. However, both in daily clinical practice and clinical trials, patients with unknown EGFR gene status (UN-EGFR-GS) are very common. In this study, we assessed efficacy and tolerability of sequential treatment of first-line pemetrexed followed by icotinib in Chinese advanced lung adenocarcinoma with UN-EGFR-GS. We analyzed 38 patients with advanced lung adenocarcinoma with UN-EGFR-GS treated with first-line pemetrexed-based chemotherapy followed by icotinib as maintenance or second-line therapy. The response rates to pemetrexed and icotinib were 21.1% and 42.1%, respectively. The median overall survival was 27.0 months (95% CI, 19.7-34.2 months). The 12-month overall survival probability was 68.4%. The most common toxicities observed in icotinib phase were rashes, diarrheas, and elevated aminotransferase. Subgroup analysis indicated that the overall survival is correlated with response to icotinib. The sequence of first-line pemetrexed-based chemotherapy followed by icotinib treatment is a promising option for advanced lung adenocarcinoma with UN-EGFR-GS in China.

  16. 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.

  17. Comparative analysis of clinicoradiologic characteristics of lung adenocarcinomas with ALK rearrangements or EGFR mutations

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, J.Y.; Zheng, J.; Chen, X.; Zhou, J.Y. [Zhejiang University, Department of Respiratory Disease, Thoracic Disease Center, First Affiliated Hospital, College of Medicine, Hangzhou (China); Yu, Z.F.; Xiao, W.B.; Jiang, L.N. [Zhejiang University, Department of Radiology, First Affiliated Hospital, College of Medicine, Hangzhou (China); Zhao, J.; Sun, K.; Wang, B.; Ding, W. [Zhejiang University, Department of Pathology, First Affiliated Hospital, College of Medicine, Hangzhou (China)

    2015-05-01

    To compare the clinicoradiologic features of tumours with echinoderm anaplastic lymphoma kinase (ALK) rearrangements, epidermal growth factor receptor (EGFR) mutations, or wild type (WT) for both genes in a cohort of patients with lung adenocarcinoma to identify useful characteristics of different gene statuses. In 346 lung adenocarcinoma patients, ALK rearrangements were confirmed with fluorescence in situ hybridisation, and EGFR mutations were determined by pyrosequencing assay. Patients were divided into three groups: ALK rearrangement (ALK+ group, n = 48), EGFR mutation (EGFR+ group, n = 166), and WT for both genes (WT group, n = 132). Chest computed tomography (CT) examinations were performed in all patients. The percentages of ground-glass opacity volume (pGGO) and tumour shadow disappearance rate (TDR) were measured using semi-automated nodule assessment software. The pGGO was significantly lower in the ALK+ group (25.1 % ± 24.3) than in the EGFR+ group (37.2 % ± 25.7, p < 0.001) and the WT group (36.1 % ± 24.6, p = 0.001). The TDR in the ALK+ group (17.3 % ± 25.1) was significantly lower than in the EGFR+ group (26.8 % ± 24.9, p = 0.002) and the WT group (25.7 % ± 24.6, p = 0.003). Solid pattern with lower incidence of lobulated border, finely spiculated margins, pleural retraction, and bubble-like lucency on CT imaging are the main characteristics of ALK rearrangement tumours. (orig.)

  18. Inhibition of EGFR nuclear shuttling decreases irradiation resistance in HeLa cells.

    Science.gov (United States)

    Wei, Hong; Zhu, Zijie; Lu, Longtao

    2017-01-01

    Cervical cancer is a leading cause of mortality in women worldwide. The resistance to irradiation at the advanced stage is the main reason for the poor prognosis and high mortality. This work aims to elucidate the molecular mechanism underlying the radio-resistance. In this study, we determined the pEGFR-T654 and pDNA-PK-T2609 expression level changes in irradiated HeLa cells treated with T654 peptide, a nuclear localization signal (NLS) inhibitor, to inhibit EGFR nuclear transport. Cell viability, cell cycle and migratory capacity were analyzed. Xenograft animal model was used to evaluate the effect of EGFR nuclear transport inhibition on the tumor growth in vivo. The enhanced translocation of nuclear EGFR in the irradiated HeLa cells correlated with the increasing level of pEGFR-T654 and pDNA-PK-T2609. Inhibition of EGFR nuclear translocation by NLS peptide inhibitor attenuated DNA damage repair in the irradiated HeLa cells, decreased cell viability and promoted cell death through arrest at G0 phase. NLS peptide inhibitor impaired the migratory capacity of irradiated HeLa cells, and negatively affected tumorigenesis in xenograft mice. This work puts forward a potential molecular mechanism of the irradiation resistance in cervical cancer cells, providing a promising direction towards an efficient therapy of cervical cancer.

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

    International Nuclear Information System (INIS)

    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 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 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 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

  20. Correlation between egfr expression and accelerated proliferation during radiotherapy of head and neck squamous cell carcinoma

    International Nuclear Information System (INIS)

    Pedicini, Piernicola; Fiorentino, Alba; Improta, Giuseppina; Storto, Giovanni; Benassi, Marcello; Orecchia, Roberto; Salvatore, Marco; Nappi, Antonio; Strigari, Lidia; Alicia Jereczek-Fossa, Barbara; Alterio, Daniela; Cremonesi, Marta; Botta, Francesca; Vischioni, Barbara; Caivano, Rocchina

    2012-01-01

    To investigate the correlation between the expression of Epidermal Growth Factor receptor (EGFr) and the reduction of the effective doubling time (T D ) during radiotherapy treatment and also to determine the dose per fraction to be taken into account when the overall treatment time (OTT) is reduced in accelerated radiotherapy of head and neck squamous cell carcinoma (HNSCC). A survey of the published papers comparing 3-years of local regional control rate (LCR) for a total of 2162 patients treated with conventional and accelerated radiotherapy and with a pretreatment assessment of EGFr expression, was made. Different values of T D were obtained by a model incorporating the overall time corrected biologically effective dose (BED) and a 3-year clinical LCR for high and low EGFr groups of patients (H EGFr and L EGFr ), respectively. By obtaining the T D from the above analysis and the sub-sites’ potential doubling time (T pot ) from flow cytometry and immunohistochemical methods, we were able to estimate the average T D for each sub-site included in the analysis. Moreover, the dose that would be required to offset the modified proliferation occurring in one day (D prolif ), was estimated. The averages of T D were 77 (27-90) 95% days in L EGFr and 8.8 (7.3-11.0) 95% days in H EGFr , if an onset of accelerated proliferation T K at day 21 was assumed. The correspondent H EGFr sub-sites’ T D were 5.9 (6.6), 5.9 (6.6), 4.6 (6.1), 14.3 (12.9) days, with respect to literature immunohistochemical (flow cytometry) data of T pot for Oral-Cavity, Oro-pharynx, Hypo-pharynx, and Larynx respectively. The D prolif for the H EGFr groups were 0.33 (0.29), 0.33 (0.29), 0.42 (0.31), 0.14 (0.15) Gy/day if α = 0.3 Gy -1 and α/β = 10 Gy were assumed. A higher expression of the EGFr leads to enhanced proliferation. This study allowed to quantify the extent of the effect which EGFr expression has in terms of reduced T D and D prolif for each head and neck sub-site

  1. SKLB188 inhibits the growth of head and neck squamous cell carcinoma by suppressing EGFR signalling.

    Science.gov (United States)

    Barzegar, Mansoureh; Ma, Shuang; Zhang, Chao; Chen, Xin; Gu, Ying; Shang, Chaowei; Jiang, Xiaojuan; Yang, Jiao; Nathan, Cherie-Ann; Yang, Shengyong; Huang, Shile

    2017-10-10

    Overexpression of epidermal growth factor receptor (EGFR) occurs in approximately 90% of head and neck squamous cell carcinoma (HNSCC), and is correlated with poor prognosis. Thus, targeting EGFR is a promising strategy for treatment of HNSCC. Several small molecule EGFR inhibitors have been tested in clinical trials for treatment of HNSCC, but none of them are more effective than the current chemotherapeutic drugs. Thus, it is urgently needed to develop novel EGFR inhibitors for HNSCC treatment. By screening an in-house focused library containing approximately 650 000 known kinase inhibitors and kinase inhibitor-like compounds containing common kinase inhibitor core scaffolds, we identified SKLB188 as a lead compound for inhibition of EGFR. The anticancer effects of SKLB188 on HNSCC cells were investigated by in vitro cell growth, cell cycle and apoptosis assays, as well as in vivo FaDu xenograft mouse model. Molecular docking, in vitro kinase profiling and western blotting were performed to characterise EGFR as the molecular target. SKLB188 inhibited HNSCC cell proliferation by inducing G 1 cell cycle arrest, which was associated with downregulating the expression of Cdc25A, cyclins D1/A and cyclin-dependent kinases (CDK2/4), and upregulating the expression of cyclin-dependent kinase (CDK) inhibitors (p21 Cip1 and p27 Kip1 ), leading to decreased phosphorylation of Rb. SKLB188 also induced caspase-dependent apoptosis of HNSCC cells by downregulating the expression of Mcl-1 and survivin. Molecular docking revealed that SKLB188 could bind to the kinase domain of EGFR through hydrogen bonds and hydrophobic interactions. In vitro kinase assay showed that SKLB188 inhibited the activity of a recombinant human EGFR very potently (IC 50 =5 nM). Western blot analysis demonstrated that SKLB188 inhibited the phosphorylation of EGFR and its downstream targets, extracellular signal-regulated protein kinases 1 and 2 (Erk1/2) and Akt in the cells. In addition, SKLB188 dose

  2. FDG-PET/CT response evaluation during EGFR-TKI treatment in patients with NSCLC

    Institute of Scientific and Technical Information of China (English)

    Matthijs; H; van; Gool; Tjeerd; S; Aukema; Koen; J; Hartemink; Renato; A; Valdés; Olmos; Houke; M; Klomp; Harm; van; Tinteren

    2014-01-01

    Over recent years,[18F]-fluorodeoxyglucose positron emission tomography acquired together with low dose computed tomography(FDG-PET/CT)has proven its role as a staging modality in patients with non-small cell lung cancer(NSCLC).The purpose of this review was to present the evidence to use FDG-PET/CT for response evaluation in patients with NSCLC,treated with epidermal growth factor receptor(EGFR)-tyrosine kinase inhibitors(TKI).All published articles from 1November 2003 to 1 November 2013 reporting on 18FFDG-PET response evaluation during EGFR-TKI treatment in patients with NSCLC were collected.In total 7studies,including data of 210 patients were eligible for analyses.Our report shows that FDG-PET/CT responseduring EGFR-TKI therapy has potential in targeted treatment for NSCLC.FDG-PET/CT response is associated with clinical and radiologic response and with survival.Furthermore FDG-PET/CT response monitoring can be performed as early as 1-2 wk after initiation of EGFR-TKI treatment.Patients with substantial decrease of metabolic activity during EGFR-TKI treatment will probably benefit from continued treatment.If metabolic response does not occur within the first weeks of EGFR-TKI treatment,patients may be spared(further)unnecessary toxicity of ineffective treatment.Refining FDG-PET response criteria may help the clinician to decide on continuation or discontinuation of targeted treatment.

  3. Anti-EGFR-Targeted Therapy for Esophageal and Gastric Cancers: An Evolving Concept

    Directory of Open Access Journals (Sweden)

    Tomislav Dragovich

    2009-01-01

    Full Text Available Cancers of the esophagus and stomach present a major health burden worldwide. In the past 30 years we have witnessed some interesting shifts in terms of epidemiology of esophago gastric cancers. Regardless of a world region, the majority of patients diagnosed with esophageal or gastric cancers die from progression or recurrence of their disease. While there are many active cytotoxic agents for esophageal and stomach cancers, their impact on the disease course has been modest at best. Median survival for patients with advanced gastroesophageal cancer is still less than a year. Therefore, novel strategies, based on our understanding of biology and genetics, are desperately needed. Epidermal growth factor receptor (EGFR pathway has been implicated in pathophysiology of many epithelial malignancies, including esophageal and stomach cancers. EGFR inhibitors, small molecule tyrosine kinase inhibitors and monoclonal antibodies, have been explored in patients with esophageal and gastric cancers. It appears that tumors of the distal esophagus and gastroesophageal junction (GEJ may be more sensitive to EGFR blockade than distal gastric adenocarcinomas. Investigations looking into potential molecular predictors of sensitivity to EGFR inhibitors for patients with esophageal and GEJ cancers are ongoing. While we are still searching for those predictors, it is clear that they will be different from ones identified in lung and colorectal cancers. Further development of EGFR inhibitors for esophageal and GEJ cancers should be driven by better understanding of EGFR pathway disregulation that drives cancer progression in a sensitive patient population.

  4. Vorinostat and metformin sensitize EGFR-TKI resistant NSCLC cells via BIM-dependent apoptosis induction.

    Science.gov (United States)

    Chen, Hengyi; Wang, Yubo; Lin, Caiyu; Lu, Conghua; Han, Rui; Jiao, Lin; Li, Li; He, Yong

    2017-11-07

    There is a close relationship between low expression of BIM and resistance to epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). Vorinostat is a pan-histone deacetylase inhibitor (HDACi) that augments BIM expression in various types of tumor cells, however, this effect is attenuated by the high expression of anti-apoptotic proteins in EGFR-TKI resistant non-small cell lung cancer (NSCLC) cells. Vorinostat in combination with metformin - a compound that can inhibit anti-apoptotic proteins expression, might cooperate to activate apoptotic signaling and overcome EGFR-TKI resistance. This study aimed to investigate the cooperative effect and evaluate possible molecular mechanisms. The results showed that vorinostat combined with gefitinib augmented BIM expression and increased the sensitivity of EGFR-TKI resistant NSCLC cells to gefitinib, adding metformin simultaneously could obviously inhibit the expression of anti-apoptotic proteins, and further increased expression levels of BIM and BAX, and as a result, further improved the sensitivity of gefitinib both on the NSCLC cells with intrinsic and acquired resistance to EGFR-TKI. In addition, autophagy induced by gefitinib and vorinostat could be significantly suppressed by metformin, which might also contribute to enhance apoptosis and improve sensitivity of gefitinib. These results suggested that the combination of vorinostat and metformin might represent a novel strategy to overcome EGFR-TKI resistance associated with BIM-dependent apoptosis in larger heterogeneous populations.

  5. Genetic variations of the A13/A14 repeat located within the EGFR 3′ untranslated region have no oncogenic effect in patients with colorectal cancer

    International Nuclear Information System (INIS)

    Sarafan-Vasseur, Nasrin; Latouche, Jean-Baptiste; Frebourg, Thierry; Sesboüé, Richard; Sefrioui, David; Tougeron, David; Lamy, Aude; Blanchard, France; Le Pessot, Florence; Di Fiore, Frédéric; Michel, Pierre; Bézieau, Stéphane

    2013-01-01

    The EGFR 3′ untranslated region (UTR) harbors a polyadenine repeat which is polymorphic (A13/A14) and undergoes somatic deletions in microsatellite instability (MSI) colorectal cancer (CRC). These mutations could be oncogenic in colorectal tissue since they were shown to result into increased EGFR mRNA stability in CRC cell lines. First, we determined in a case control study including 429 CRC patients corresponding to different groups selected or not on age of tumor onset and/or familial history and/or MSI, whether or not, the germline EGFR A13/A14 polymorphism constitutes a genetic risk factor for CRC; second, we investigated the frequency of somatic mutations of this repeat in 179 CRC and their impact on EGFR expression. No statistically significant difference in allelic frequencies of the EGFR polyA repeat polymorphism was observed between CRC patients and controls. Somatic mutations affecting the EGFR 3′UTR polyA tract were detected in 47/80 (58.8%) MSI CRC versus 0/99 microsatellite stable (MSS) tumors. Comparative analysis in 21 CRC samples of EGFR expression, between tumor and non malignant tissues, using two independent methods showed that somatic mutations of the EGFR polyA repeat did not result into an EGFR mRNA increase. Germline and somatic genetic variations occurring within the EGFR 3′ UTR polyA tract have no impact on CRC genetic risk and EGFR expression, respectively. Genotyping of the EGFR polyA tract has no clinical utility to identify patients with a high risk for CRC or patients who could benefit from anti-EGFR antibodies

  6. Research progress on criteria for discontinuation of EGFR inhibitor therapy

    Directory of Open Access Journals (Sweden)

    Zhuang HQ

    2012-10-01

    Full Text Available Hong-qing Zhuang, Zhi-yong Yuan, Jun Wang, Ping Wang, Lu-jun Zhao, Bai-lin ZhangDepartment of Radiotherapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin Key Laboratory of Cancer Prevention and Therapy, Tianjin Lung Cancer Center, Tianjin, People's Republic of ChinaAbstract: The clinical success of the epidermal growth factor receptor (EGFR tyrosine kinase inhibitors (TKI as therapeutic agents has prompted great interest in their further development and clinical testing for a wide variety of malignancies. However, most studies have focused on the efficacy of TKI, and few studies have been done on the criteria for their discontinuation. The current standard for drug discontinuation is “until progression”, based on change in tumor size. However, tumor size is not related to the gene expression which determines the efficacy of TKI in the final analysis, and it is also difficult to make a thorough and correct prediction based on tumor size when the TKI is discontinued. Nevertheless, clinical evaluation of the criteria for TKI discontinuation is still in its early days. Some promising findings have started to emerge. With the improving knowledge of EGFR and its inhibitors, it is expected that the criteria for discontinuation of EGFR inhibitor therapy will become clearer.Keywords: epidermal growth factor receptor, drug discontinuation, acquired drug-resistance

  7. Substoichiometric neutron activation determination of gold

    International Nuclear Information System (INIS)

    Mitchell, J.W.; Riley, J.E. Jr.; Payne, V.

    1978-01-01

    A highly precise and selective method is described for the determination of traces of gold by substoichiometric extraction from hydrochloric acid with tri-n-octylphosphine sulfide in cyclohexane following thermal neutron activation. Fundamental aspects of the extraction system are discussed and results are reported for the determination of gold in an effluent from a recovery process containing a complexed species of gold and unknown amounts of cyanide, citrate, phosphate, potassium and sodium. Other constituents of the effluent stream include traces of the transition elements Co, Ni, Fe, Cu, Zn, Pb and Sn at concentrations less than 50 ppm. One hour was allowed for the Au 3+ carrier and the 198 Au complexed species in samples and standards to oxidize, exchange, and reach chemical equilibrium. Samples were then equilibrated by shaking with the organic phase for thirty min. The percentage extractions (%E) for the substoichiometric separation of gold from the effluent and from the corresponding comparison standards were monitored. The mean percentage extractions for the substoichiometric separations of carrier from the effluent, and its corresponding standard were 75.3 and 59.3, respectively. These data are estimated to be accurate within +-2.0%. (T.G.)

  8. Coincidence method for determination of radionuclides activities

    International Nuclear Information System (INIS)

    Andrukhovich, S.K.; Berestov, A.V.; Rudak, E.A.

    2004-01-01

    The radon and radium activity measurements using six-crystal gamma-gamma coincidence, 4 -spectrometer PRIPJAT and radioactivity measurements in different samples of meat and vegetation by 32-crystal spectrometer ARGUS, are described. Radiation detector with 4 -geometry provides higher efficiency, and therefore shorter counting time than a detector without such geometry. However, its application is limited by the fact that obtained spectrum contains summing peaks of all γ-quanta registered in coincidence. Multiparameter information on coincident photon emission can be obtained only by a detection system where the 4 -geometry is made by many detectors, such are both the PRIPJAT and the ARGUS - γ-coincidence spectrometer of the Crystal Ball type in the Institute of Physics, Minsk [1,2]. There are other characteristics, as background conditions, energy and time resolution, makes it ve suitable for investigation of rare decays and interactions, cascade transitions, k intensity radiations etc. We are developing a method of 2 26R a and 2 26 Rn measurement by a multidetector 4 -spectrometer. The method is based on coincidence counting of γ-rays from two step cascade transitions that follow - decay of 2 14 Bi. Its application to the PRIPL spectrometer, which has 6 Nal(Tl) detectors, is presented here, as well as the method of the determination of radionuclide activities based on the registration of the cascades intensity of γ-rays of different multiplicity using ARGUS

  9. Design, Synthesis and Biological Evaluation of Benzohydrazide Derivatives Containing Dihydropyrazoles as Potential EGFR Kinase Inhibitors

    Directory of Open Access Journals (Sweden)

    Hai-Chao Wang

    2016-08-01

    Full Text Available A series of novel benzohydrazide derivatives containing dihydropyrazoles have been synthesized as potential epidermal growth factor receptor (EGFR kinase inhibitors and their biological activities as potential antiproliferative agents have been evaluated. Among these compounds, compound H20 exhibited the most potent antiproliferative activity against four cancer cell line variants (A549, MCF-7, HeLa, HepG2 with IC50 values of 0.46, 0.29, 0.15 and 0.21 μM respectively, which showed the most potent EGFR inhibition activities (IC50 = 0.08 μM for EGFR. Molecular modeling simulation studies were performed in order to predict the biological activity and activity relationship (SAR of these benzohydrazide derivatives. These results suggested that compound H20 may be a promising anticancer agent.

  10. Targeting Signal Transducers and Activators of Transcription-3 (STAT3) as a Novel Strategy in Sensitizing Breast Cancer to EGFR-Targeted Therapy

    Science.gov (United States)

    2009-06-01

    Figure 4A). Using the Median-effect analysis (Chou and Talalay 1984) that computes combination index (CI), we determined whether AG490 and Iressa...H3578T cells were subjected Median-effect analysis to derive CI that indicates synergistic effect (CIə), additive effect (CI=1) and antagonistic effect...Wrzeszczynska, G. Devgan, Y. Zhao, R. G. Pestell , C. Albanese, and J. E. Darnell, Jr. 1999. Stat3 as an oncogene. Cell 98 (3):295-303. Chan, K. S., S. Sano, K

  11. 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.

  12. MAXIMIZATION OF DNA DAMAGE TO MGMT(+ EGFR(+ GBM CELLS USING OPTIMAL COMBINATION OF TEMOZOLOMIDE-ANTI EGFR MONOCLONAL ANTIBODY NIMOTUZUMAB

    Directory of Open Access Journals (Sweden)

    M. A. M. Inggas

    2015-09-01

    Full Text Available Background: Glioblastoma multiforme (GBM is the most aggressive primary brain tumor in adultswith dismal prognosis due to the unavailability of an effective therapy. Up to now, there had been no definitive studies published on EGFR inhibition therapy as a chemosensitizer for GBM therapy using Temozolomide (TMZ. This study aims to reveal the most effective method and timing to administer TMZ-anti EGFR targeted therapy which causes maximal DNA damage on GBM cells.Methods: Various regimens of anti EGFR monoclonal antibody Nimotuzumab (NMZ was administered in different combinations with TMZ, performed on U87MG MGMT(+ EGFR(+ cells. The effectiveness of the combinations were evaluated by measuring yH2AX levels which reflects the degree of DNA damage. One-way Anova and LSD tests were performed to determine the effects of each treatment with p<0.05. Results and discussion: the mean SD of yH2AX of each treatment was: 11,90±1,25 for the control group; 29.33±1.91 for NMZ alone; 28.13±1.58 for TMZ alone; 41.53±3.51 for concurrent use; 35.67 ±2.65 for NMZ after 24 hours TMZ; 31.87±2.94 for NMZ after 48 hours TMZ; 39.57±4.2 for TMZ after 24 hours NMZ; and 35.93 ±3.56 for TMZ after 48 hours NMZ. The administration of TMZ concurrent with or after 24 hours NMZ gives the highest amount of DNA damage to GBM cells. Conclusion: The administration of Nimotuzumab targeted therapy up to 24 hours before Temozolomide chemotherapy has been proven to be effective in maximizing the amount of DNA damage done to GBM cells in vitro. 

  13. Radiotherapy of non-small-cell lung cancer in the era of EGFR gene mutations and EGF receptor tyrosine kinase inhibitors.

    Science.gov (United States)

    Moschini, Ilaria; Dell'Anna, Cristina; Losardo, Pier Luigi; Bordi, Paola; D'Abbiero, Nunziata; Tiseo, Marcello

    2015-01-01

    Non-small-cell lung cancer (NSCLC) occurs, approximately, in 80-85% of all cases of lung cancer. The majority of patients present locally advanced or metastatic disease when diagnosed, with poor prognosis. The discovery of activating mutations in the EGFR gene has started a new era of personalized treatment for NSCLC patients. To improve the treatment outcome in patients with unresectable NSCLC and, in particular, EGFR mutated, a combined strategy of radiotherapy and medical treatment can be undertaken. In this review we will discuss preclinical data regarding EGF receptor (EGFR) tyrosine kinase inhibitors (TKIs) and radiotherapy, available clinical trials investigating efficacy and toxicity of combined treatment (thoracic or whole brain radiotherapy and EGFR-TKIs) and, also, the role of local radiation in mutated EGFR patients who developed EGFR-TKI resistance.

  14. Detection of EGFR mutations in plasma and biopsies from non-small cell lung cancer patients by allele-specific PCR assays

    DEFF Research Database (Denmark)

    Weber, Britta; Meldgaard, Peter; Hager, Henrik

    2014-01-01

    samples with allele-specific PCR assays. METHODS: Pairs of the diagnostic biopsy and plasma obtained just prior to start of erlotinib treatment were collected from 199 patients with adenocarcinoma of non-small-cell lung cancer. DNA from both sample types was isolated and examined for the presence...... of mutations in exons 18-21 of the EGFR gene, employing the cobas(®) EGFR Tissue Test and cobas(®) EGFR Blood Test (in development, Roche Molecular Systems, Inc., CA, USA). RESULTS: Test results were obtained in all 199 (100%) plasma samples and 196/199 (98%) of the biopsies. EGFR-activating mutations were...... identified in 24/199 (12%) plasma samples and 28/196 (14%) biopsy samples, and 17/196 (9%) matched pairs contained the same mutation. Six EGFR mutations were present only in plasma samples but not in the biopsy samples. The overall concordance of the EGFR gene mutations detected in plasma and biopsy tissue...

  15. [Efficacy of icotinib for advanced non-small cell lung cancer patients with EGFR status identified].

    Science.gov (United States)

    Song, Zhengbo; Yu, Xinmin; Cai, Jufen; Shao, Lan; Lin, Baochai; He, Chunxiao; Zhang, Beibei; Zhang, Yiping

    2013-03-01

    As the first epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) in China, icotinib shows promising anticancer activity in vitro and vivo. The phase III clinical study (ICOGEN) showed that icotinib has a good efficacy and tolerability in Chinese patients with advanced non-small cell lung cancer (NSCLC) compared with gefitinib. This retrospective study aims to evaluate the efficacy and tolerability of icotinib monotherapy for advanced NSCLC patients with EGFR mutation and wild-type patients in our hospital. Patients with advanced NSCLC who were treated with icotinib in Zhejiang Cancer Hospital were retrospectively analyzed from August, 2011 to August, 2012. Survival was estimated using Kaplan-Meier analysis and Log-rank tests. The clinical data of 49 patients (13 with wild-type and 36 with EGFR mutation) with NSCLC were enrolled in the current study. The patients' overall objective response rate (ORR) was 58.3% and the disease control rate (DCR) in 36 EGFR mutation patients was 88.9%. The ORR was 7.7% and DCR was 53.8% in the wild-type patients. Median progression-free survival (PFS) with icotinib treatment in EGFR mutation patients was 9.5 months and 2.2 months in wild-type patients (Picotinib as first-line and 17 in further-line treatment. The PFS was 9.5 months in the first-line and 8.5 months for second-line or further-line patients (P=0.41). Median overall survival (OS) in EGFR mutation patients was not reached, but was 12.6 months in wild-type patients. Most of the drug-related adverse events were mild (grade I or II) and reversible with no grade IV toxicity. Icotinib monotherapy showed significant antitumor activity in advanced NSCLC EGFR mutation patients. The toxicity was well tolerated and acceptable.

  16. Chronic activation of wild-type epidermal growth factor receptor and loss of Cdkn2a cause mouse glioblastoma formation.

    Science.gov (United States)

    Acquaviva, Jaime; Jun, Hyun Jung; Lessard, Julie; Ruiz, Rolando; Zhu, Haihao; Donovan, Melissa; Woolfenden, Steve; Boskovitz, Abraham; Raval, Ami; Bronson, Roderick T; Pfannl, Rolf; Whittaker, Charles A; Housman, David E; Charest, Al

    2011-12-01

    Glioblastoma multiforme (GBM) is characterized by overexpression of epidermal growth factor receptor (EGFR) and loss of the tumor suppressors Ink4a/Arf. Efforts at modeling GBM using wild-type EGFR in mice have proven unsuccessful. Here, we present a unique mouse model of wild-type EGFR-driven gliomagenesis. We used a combination of somatic conditional overexpression and ligand-mediated chronic activation of EGFR in cooperation with Ink4a/Arf loss in the central nervous system of adult mice to generate tumors with the histopathologic and molecular characteristics of human GBMs. Sustained, ligand-mediated activation of EGFR was necessary for gliomagenesis, functionally substantiating the clinical observation that EGFR-positive GBMs from patients express EGFR ligands. To gain a better understanding of the clinically disappointing EGFR-targeted therapies for GBM, we investigated the molecular responses to EGFR tyrosine kinase inhibitor (TKI) treatment in this model. Gefitinib treatment of primary GBM cells resulted in a robust apoptotic response, partially conveyed by mitogen-activated protein kinase (MAPK) signaling attenuation and accompanied by BIM(EL) expression. In human GBMs, loss-of-function mutations in the tumor suppressor PTEN are a common occurrence. Elimination of PTEN expression in GBM cells posttumor formation did not confer resistance to TKI treatment, showing that PTEN status in our model is not predictive. Together, these findings offer important mechanistic insights into the genetic determinants of EGFR gliomagenesis and sensitivity to TKIs and provide a robust discovery platform to better understand the molecular events that are associated with predictive markers of TKI therapy.

  17. Icotinib in Patients with Pretreated Advanced Esophageal Squamous Cell Carcinoma with EGFR Overexpression or EGFR Gene Amplification: A Single-Arm, Multicenter Phase 2 Study.

    Science.gov (United States)

    Huang, Jing; Fan, Qingxia; Lu, Ping; Ying, Jianming; Ma, Changwu; Liu, Wei; Liu, Ying; Tan, Fenlai; Sun, Yan

    2016-06-01

    Epidermal growth factor receptor (EGFR) has been reported to be overexpressed and amplified in a high percentage of patients with esophageal squamous cell carcinoma (ESCC). The activity of icotinib, an EGFR tyrosine kinase inhibitor, was assessed in previously treated ESCC with EGFR overexpression or amplification. For this phase 2, single-arm, multicenter trial undertaken at six hospitals in China, we included Chinese patients with previously treated, histologically confirmed advanced ESCC and EGFR overexpression (immunohistochemical staining sore of 3+) or amplification (positive fluorescence in situ hybridization result). These patients received oral icotinib (250 mg, three times daily).The primary end point was the proportion of patients with objective responses as assessed by an independent radiology review committee. Between December 5, 2013, and May 28, 2015, a total of 281 patients were screened. Fifty-four eligible patients were enrolled. Nine responses were observed, including one complete response and eight partial responses, and 16 patients had stable disease, resulting in a 16.7% objective response rate (95% confidence interval [CI]: 6.7-26.6) and 46.3% disease control rate (95% CI: 33.0-59.6). The median progression-free survival and overall survival times were 52 (95% CI: 40-95) days and 153 (95% CI: 139-218) days, respectively. A total of 43 patients experienced at least one adverse event, but most were only grade 1 to 2 in severity. The most frequent was rash (48.1%), followed by diarrhea (22.2%). Icotinib showed favorable activity in patients with advanced, previously treated ESCC with EGFR overexpression or amplification. These findings suggest further research into EGFR overexpression or amplification for selecting responsive patients. Copyright © 2016 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

  18. Gefitinib: a pharmacoeconomic profile of its use in patients with Non Small Cell Lung Cancer EGFR+

    Directory of Open Access Journals (Sweden)

    Viola Sacchi

    2011-06-01

    Full Text Available Lung cancer is the most common form of cancer with the highest incidence worldwide. The mortality rates are highest in males and second highest in females, after breast cancer. The genetic predisposition to Non Small Cell Lung Cancer (NSCLC is still under investigation, however, studies have shown that the Epidermal Growth Factor Receptor (EGFR, a receptor tyrosine kinase is frequently over-expressed and activated to a phosphorylated state in NSCLC. The activity of EGFR in cancer cells results in the phosphorylation of downstream proteins that promote cell proliferation, invasion, metastasis, and inhibition of apoptosis. Targeting the EGFR pathway therefore constitutes a relevant strategy for cancer therapy. Gefitinib is a selective inhibitor of the EGFR tyrosine kinase and is indicated for the treatment of adult patients with locally advanced or metastatic NSCLC with activating mutations of EGFR-TK. From the pharmacoeconomic point of view gefitinib is dominant (more effective and less expensive compared to the alternatives. In conclusion, gefitinib is a treatment option for NSCLC tumors with a high clinical and economic value in the Italian setting.

  19. EGFR/Ras Signaling Controls Drosophila Intestinal Stem Cell Proliferation via Capicua-Regulated Genes.

    Directory of Open Access Journals (Sweden)

    Yinhua Jin

    2015-12-01

    Full Text Available Epithelial renewal in the Drosophila intestine is orchestrated by Intestinal Stem Cells (ISCs. Following damage or stress the intestinal epithelium produces ligands that activate the epidermal growth factor receptor (EGFR in ISCs. This promotes their growth and division and, thereby, epithelial regeneration. Here we demonstrate that the HMG-box transcriptional repressor, Capicua (Cic, mediates these functions of EGFR signaling. Depleting Cic in ISCs activated them for division, whereas overexpressed Cic inhibited ISC proliferation and midgut regeneration. Epistasis tests showed that Cic acted as an essential downstream effector of EGFR/Ras signaling, and immunofluorescence showed that Cic's nuclear localization was regulated by EGFR signaling. ISC-specific mRNA expression profiling and DNA binding mapping using DamID indicated that Cic represses cell proliferation via direct targets including string (Cdc25, Cyclin E, and the ETS domain transcription factors Ets21C and Pointed (pnt. pnt was required for ISC over-proliferation following Cic depletion, and ectopic pnt restored ISC proliferation even in the presence of overexpressed dominant-active Cic. These studies identify Cic, Pnt, and Ets21C as critical downstream effectors of EGFR signaling in Drosophila ISCs.

  20. EGFR mutation frequency and effectiveness of erlotinib

    DEFF Research Database (Denmark)

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

    2014-01-01

    mutation (S768I), and two complex mutations. Seven percent of the patients were never smokers. The differences in median progression-free survival and overall survival between the mutated group and the wild-type group were 8.0 vs. 2.5 months, p...-1 vs. 2-3) and line of treatment (1st vs. 2nd and 3rd) had no influence on outcome in EGFR-mutated patients. CONCLUSION: We found a higher frequency of EGFR mutations than expected in a cohort with less than 10% never smokers. The outcome after treatment with erlotinib was much better in patients......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...

  1. Clinical Characteristics and Outcomes of Lung Cancer Patients 
with EGFR Mutations in Exons 19 and 21

    Directory of Open Access Journals (Sweden)

    Renwang LIU

    2014-11-01

    Full Text Available Background and objective Studies on the epidermal growth factor receptor (EGFR signaling pathways and the therapeutic effects of EGFR-tyrosine kinase inhibitors (EGFR-TKIs have recently proven that targeted therapy has a major role in the treatment of lung cancer. However, the therapeutic effects of EGFR-TKIs on lung cancers with different EGFR mutation subtypes remain unclear. And if there is a significant difference in the effects of EGFR-TKIs, the mechanisms for the difference remain unclear. The aim of this study was to investigate the clinical importance of EGFR mutations in exons 19 and 21 of lung cancer patients and to compare the outcomes of these patients. Methods The study recruited 113 patients who had non-small cell lung cancer (NSCLC with EGFR mutations. EGFR mutations were detected for 47 patients using Real-time PCR or DNA sequencinag. The mutations of the remaining patients were determined using xTag-EGFR liquid chip technology. All stages I-III patients underwent radical resection followed by 4 cycles of postoperative chemotherapy. Patients with pleural metastases underwent pleural biopsy, pleurodesis, and chemotherapy only. Patients with distant metastases underwent biopsy and chemotherapy only. Collected clinical data were analyzed using SPSS 19.0 software. Results EGFR exon mutations 19 and 21 were found in 56 and 57 patients, respectively. The mean age of patients with exon 19 mutations was lower than the age of the patients with exon 21 mutations (57.02±11.31 years vs 62.25±7.76 years, respectively; P0.05 between the patients with exon 19 and 21 mutations; and survival analysis of 91 (80.5% patients with complete clinical data found no differences in overall survival. Stratification analysis found out that patients with exon 19 mutations had longer overall survival associated with age>61 years, male gender, ever smoking, and stage IV disease; although the differences were not significant. Conclusion Compared to the lung

  2. Phase III study of afatinib or cisplatin plus pemetrexed in patients with metastatic lung adenocarcinoma with EGFR mutations.

    LENUS (Irish Health Repository)

    Sequist, Lecia V

    2013-09-20

    The LUX-Lung 3 study investigated the efficacy of chemotherapy compared with afatinib, a selective, orally bioavailable ErbB family blocker that irreversibly blocks signaling from epidermal growth factor receptor (EGFR\\/ErbB1), human epidermal growth factor receptor 2 (HER2\\/ErbB2), and ErbB4 and has wide-spectrum preclinical activity against EGFR mutations. A phase II study of afatinib in EGFR mutation-positive lung adenocarcinoma demonstrated high response rates and progression-free survival (PFS).

  3. Prediction of sensitivity to gefitinib/erlotinib for EGFR mutations in NSCLC based on structural interaction fingerprints and multilinear principal component analysis.

    Science.gov (United States)

    Zou, Bin; Lee, Victor H F; Yan, Hong

    2018-03-07

    Non-small cell lung cancer (NSCLC) with activating EGFR mutations, especially exon 19 deletions and the L858R point mutation, is particularly responsive to gefitinib and erlotinib. However, the sensitivity varies for less common and rare EGFR mutations. There are various explanations for the low sensitivity of EGFR exon 20 insertions and the exon 20 T790 M point mutation to gefitinib/erlotinib. However, few studies discuss, from a structural perspective, why less common mutations, like G719X and L861Q, have moderate sensitivity to gefitinib/erlotinib. To decode the drug sensitivity/selectivity of EGFR mutants, it is important to analyze the interaction between EGFR mutants and EGFR inhibitors. In this paper, the 30 most common EGFR mutants were selected and the technique of protein-ligand interaction fingerprint (IFP) was applied to analyze and compare the binding modes of EGFR mutant-gefitinib/erlotinib complexes. Molecular dynamics simulations were employed to obtain the dynamic trajectory and a matrix of IFPs for each EGFR mutant-inhibitor complex. Multilinear Principal Component Analysis (MPCA) was applied for dimensionality reduction and feature selection. The selected features were further analyzed for use as a drug sensitivity predictor. The results showed that the accuracy of prediction of drug sensitivity was very high for both gefitinib and erlotinib. Targeted Projection Pursuit (TPP) was used to show that the data points can be easily separated based on their sensitivities to gefetinib/erlotinib. We can conclude that the IFP features of EGFR mutant-TKI complexes and the MPCA-based tensor object feature extraction are useful to predict the drug sensitivity of EGFR mutants. The findings provide new insights for studying and predicting drug resistance/sensitivity of EGFR mutations in NSCLC and can be beneficial to the design of future targeted therapies and innovative drug discovery.

  4. Phase I study of icotinib, an EGFR tyrosine kinase inhibitor combined with IMRT in nasopharyngeal carcinoma.

    Science.gov (United States)

    Hu, Wei; Wang, Wei; Yang, Peinong; Zhou, Chao; Yang, Weifang; Wu, Bo; Lu, Hongsheng; Yang, Haihua

    2015-01-01

    Epidermal growth factor receptor (EGFR) is a new target for nasopharyngeal carcinoma (NPC) therapy. This prospective phase I study sought to determine the safety and recommended phase II dose of icotinib, a novel highly selective oral EGFR tyrosine kinase inhibitor, in combination with intensity-modulated radiotherapy (IMRT) in patients with NPC. Eligible patients with NPC received escalating doses of icotinib during IMRT. We treated six patients at a particular dose level until the maximum tolerated dose (MTD) was determined. The starting dose was 125 mg, once-daily and the dose was escalated to another level 125 mg, twice- and thrice- daily, until dose-limiting toxicity (DLT) occurred in two or more patients at a dose level. Expression and mutation analysis of EGFR were performed in all cases. A total of twelve patients were enrolled. Three patients experienced DLT (250 mg/day cohort) and MTD was 125 mg/day. Mucositis toxicity appears to be the major DLT. While EGFR expression in tumor tissue was detected in 75% (9/12) patients, EGFR mutation was detected in 16.67% (1/6) patients in 125 mg/day cohort, and 50% (3/6) in 250 mg/day cohort. The combination of icotinib (125 mg/day) and IMRT in patients with locally NPC had an acceptable safety profile and was well tolerated.

  5. Navigating into the binding pockets of the HER family protein kinases: discovery of novel EGFR inhibitor as antitumor agent

    Directory of Open Access Journals (Sweden)

    Liu W

    2015-07-01

    Full Text Available Wei Liu,1,* Jin-Feng Ning,2,* Qing-Wei Meng,1 Jing Hu,1 Yan-Bin Zhao,1 Chao Liu,3 Li Cai11The Fourth Department of Medical Oncology, Harbin Medical University Cancer Hospital, 2The Thoracic Surgery Department, Harbin Medical University Cancer Hospital, Harbin, People’s Republic of China; 3General Surgery Department, Mudanjiang Guanliju Central Hospital, Mishan, Heilongjiang Province, People’s Republic of China*These authors contributed equally to this workAbstract: The epidermal growth factor receptor (EGFR family has been validated as a successful antitumor drug target for decades. Known EGFR inhibitors were exposed to distinct drug resistance against the various EGFR mutants within non-small-cell lung cancer (NSCLC, particularly the T790M mutation. Although so far a number of studies have been reported on the development of third-generation EGFR inhibitors for overcoming the resistance issue, the design procedure largely depends on the intuition of medicinal chemists. Here we retrospectively make a detailed analysis of the 42 EGFR family protein crystal complexes deposited in the Protein Data Bank (PDB. Based on the analysis of inhibitor binding modes in the kinase catalytic cleft, we identified a potent EGFR inhibitor (compound A-10 against drug-resistant EGFR through fragment-based drug design. This compound showed at least 30-fold more potency against EGFR T790M than the two control molecules erlotinib and gefitinib in vitro. Moreover, it could exhibit potent HER2 inhibitory activities as well as tumor growth inhibitory activity. Molecular docking studies revealed a structural basis for the increased potency and mutant selectivity of this compound. Compound A-10 may be selected as a promising candidate in further preclinical studies. In addition, our findings could provide a powerful strategy to identify novel selective kinase inhibitors on the basis of detailed kinase–ligand interaction space in the PDB.Keywords: EGFR, kinase

  6. EGFR Activation by Spatially Restricted Ligands

    Science.gov (United States)

    2006-06-01

    the level of ligand production, that result in human breast cancer. We have integrated genetic and biochemical methods to study (1) the effects of a...and spindle-B encode components of the RAD52 DNA repair pathway and affect meiosis and patterning in Drosophila oogenesis. Genes Dev 12, 2711-2723...findings contained in this report are those of the author(s) and should not be construed as an official Department of the Army position, policy or decision

  7. 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.

  8. SMOC Binds to Pro-EGF, but Does Not Induce Erk Phosphorylation via the EGFR.

    Science.gov (United States)

    Thomas, J Terrig; Chhuy-Hy, Lina; Andrykovich, Kristin R; Moos, Malcolm

    2016-01-01

    In an attempt to identify the cell-associated protein(s) through which SMOC (Secreted Modular Calcium binding protein) induces mitogen-activated protein kinase (MAPK) signaling, the epidermal growth factor receptor (EGFR) became a candidate. However, although in 32D/EGFR cells, the EGFR was phosphorylated in the presence of a commercially available human SMOC-1 (hSMOC-1), only minimal phosphorylation was observed in the presence of Xenopus SMOC-1 (XSMOC-1) or human SMOC-2. Analysis of the commercial hSMOC-1 product demonstrated the presence of pro-EGF as an impurity. When the pro-EGF was removed, only minimal EGFR activation was observed, indicating that SMOC does not signal primarily through EGFR and its receptor remains unidentified. Investigation of SMOC/pro-EGF binding affinity revealed a strong interaction that does not require the C-terminal extracellular calcium-binding (EC) domain of SMOC or the EGF domain of pro-EGF. SMOC does not appear to potentiate or inhibit MAPK signaling in response to pro-EGF, but the interaction could provide a mechanism for retaining soluble pro-EGF at the cell surface.

  9. Epidermal to Mesenchymal Transition and Failure of EGFR-Targeted Therapy in Glioblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Pala, Andrej; Karpel-Massler, Georg [Department of Neurosurgery, University of Ulm School of Medicine, Steinhövelstrasse 9, Ulm D-89077 (Germany); Kast, Richard Eric [Department of Psychiatry, University of Vermont, 22 Church Street, Burlington, VT 05401 (United States); Wirtz, Christian Rainer; Halatsch, Marc-Eric, E-mail: marc-eric.halatsch@uniklinik-ulm.de [Department of Neurosurgery, University of Ulm School of Medicine, Steinhövelstrasse 9, Ulm D-89077 (Germany)

    2012-05-08

    Glioblastoma multiforme (GBM), the most common primary brain tumor in adults, is almost never curable with the current standard treatment consisting of surgical resection, irradiation and temozolomide. The prognosis remains poor despite undisputable advances in the understanding of this tumor’s molecular biology and pathophysiology, which unfortunately has so far failed to translate into a meaningful clinical benefit. Dysregulation and a resulting prominent pathophysiological role of the epidermal growth factor receptor (EGFR) have been identified in several different malignant tumor entities, GBM among them. The EGFR is overexpressed in about 40% of GBM cases, and half of these coexpress a mutant, constitutively activated subtype, EGFRvIII. Unfortunately, recent trials studying with therapeutic approaches targeted against the EGFR and EGFRvIII have failed to meet expectations, with only a minority of patients responding despite evidence of good in vitro and rodent model activity. Having potentially high relevance within this context, epithelial to mesenchymal transition (EMT) is a phenomenon associated with early stages of carcinogenesis, cancer invasion and recurrence. During EMT, epithelial cells lose many of their epithelial characteristics, prominently E-cadherin expression, and acquire properties that are typical for mesenchymal cells such as the expression of vimentin. Epithelial to mesenchymal transition has been specifically demonstrated in GBM. In this review, we summarize the evidence that EMT may precipitate GBM resistance to EGFR-targeted therapy, and may thus be among the principal factors contributing to the clinical failure of targeted therapy against EGFR and EGFRvIII.

  10. Activity determination of radionuclides for diagnostic and therapy

    International Nuclear Information System (INIS)

    Kossert, Karsten

    2013-01-01

    The application of radionuclides plays in medicine an important role and requires reliable activity determination. The PTB provides for this activity normals and determines the activity of the presented sources. The article describes, how activity determinations in the PTB occur, and by which ways this can be used for nuclear medicine. Research and development works in the PTB are just so illuminated as the determination of nuclide data of some isotopes relevant for medicine.

  11. Guanylate binding protein 1 is a novel effector of EGFR-driven invasion in glioblastoma.

    Science.gov (United States)

    Li, Ming; Mukasa, Akitake; Inda, Maria del-Mar; Zhang, Jianhua; Chin, Lynda; Cavenee, Webster; Furnari, Frank

    2011-12-19

    Although GBP1 (guanylate binding protein 1) was among the first interferon-inducible proteins identified, its function is still largely unknown. Epidermal growth factor receptor (EGFR) activation by amplification or mutation is one of the most frequent genetic lesions in a variety of human tumors. These include glioblastoma multiforme (GBM), which is characterized by independent but interrelated features of extensive invasion into normal brain parenchyma, rapid growth, necrosis, and angiogenesis. In this study, we show that EGFR activation promoted GBP1 expression in GBM cell lines through a signaling pathway involving Src and p38 mitogen-activated protein kinase. Moreover, we identified YY1 (Yin Yang 1) as the downstream transcriptional regulator regulating EGFR-driven GBP1 expression. GBP1 was required for EGFR-mediated MMP1 (matrix metalloproteinase 1) expression and glioma cell invasion in vitro. Although deregulation of GBP1 expression did not affect glioma cell proliferation, overexpression of GBP1 enhanced glioma cell invasion through MMP1 induction, which required its C-terminal helical domain and was independent of its GTPase activity. Reducing GBP1 levels by RNA interference in invasive GBM cells also markedly inhibited their ability to infiltrate the brain parenchyma of mice. GBP1 expression was high and positively correlated with EGFR expression in human GBM tumors and cell lines, particularly those of the neural subtype. Together, these findings establish GBP1 as a previously unknown link between EGFR activity and MMP1 expression and nominate it as a novel potential therapeutic target for inhibiting GBM invasion.

  12. Inhibition of tumor growth by targeted anti-EGFR/IGF-1R Nanobullets depends on efficient blocking of cell survival pathways

    NARCIS (Netherlands)

    van der Meel, Roy; Oliveira, Sabrina; Altintas, Isil; Heukers, R.; Pieters, Ebel H.E.; van Bergen en Henegouwen, Paul M.P.; Storm, Gerrit; Hennink, Wim E.; Kok, Robbert J.; Schiffelers, Raymond M.

    2013-01-01

    The clinical efficacy of epidermal growth factor receptor (EGFR)-targeted inhibitors is limited due to resistance mechanisms of the tumor such as activation of compensatory pathways. Crosstalk between EGFR and insulin-like growth factor 1 (IGF-1R) signaling has been frequently described to be

  13. Detection and Analysis of EGFR and KRAS Mutations 
in the Patients with Lung Squamous Cell Carcinomas

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    Hui ZHANG

    2015-10-01

    Full Text Available Background and objective Activating mutations in epidermal growth factor receptor (EGFR and KRAS are important markers in non-small cell lung cancer. However, EGFR and KRAS gene mutations in lung squamous cell carcinoma are rarely reported. The aim of this study was to analyze EGFR and KRAS gene mutation rate and their relationship with clinical features in patients with lung squamous cell carcinomas. Methods A total of 139 patients undergoing treatment for naïve lung squamous cell carcinomas with tumor tissue samples available for testing were recruited. EGFR and KRAS mutation statuses of the tumor samples were detected using a mutant enriched liquid chip. Results Of the 139 cases of lung squamous cell carcinoma, EGFR mutations were detected in 25 cases (18%, KRAS mutations were detected in 7 cases (5%, and the presence of both EGFR and KRAS mutations was detected in 1 case (0.7%. EGFR mutations occurred more often in females than in males (33.3% vs 16.5% and in patients that never smoked than in those who smoke (29.6% vs 16.1%. However, the difference did not reach statistical significance (P>0.05. No significant differences were observed in age, stage, and different biopsy type. KRAS mutations occurred more often in males than in females (5.5% vs 0%, but the difference did not reach statistical significance (P>0.05. No significant differences were observed in age, stage, different biopsy type, and smoking status (P>0.05. Conclusion EGFR and KRAS mutations were low in lung squamous cell carcinomas, and had no significant correlation with clinical features. Before using tyrosine kinase inhibitor targeted therapy, EGFR and KRAS mutations should be detected in patients with lung squamous cell carcinomas.

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

    Science.gov (United States)

    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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. The anti-epidermal growth factor receptor (EGFR) monoclonal antibody, C225, enhances radiation-induced apoptosis in primary glioma cell lines through mediation of MAPK/JNK/p38 signaling pathways

    International Nuclear Information System (INIS)

    Chakravarti, A.; Noll, E.; Black, P.M.; Loeffler, J.S.

    2001-01-01

    Purpose: Increasing evidence suggests that signaling mediated by the epidermal growth factor receptor (EGFR) pathway contributes to radiation resistance. The anti-EGFR monoclonal antibody, C225, has been shown to enhance radiation response for several tumor types in preclinical models. Malignant gliomas are known to express, and quite frequently overexpress, EGFR. Our objectives in this study were to 1) Evaluate the efficacy of C225 as a radiation response modifier in EGFR-expressing glioma cell lines and to 2) Investigate the underlying molecular mechanisms mediating C225-induced enhancement of radiation response. Materials and Methods: Twelve EGFR-expressing glioma cells lines, established from patient tumors, were used for this study. Cells were incubated with C225, irradiated, and then evaluated for radiation response. Assays used to evaluate efficacy of C225-mediated radiosensitization included time-course apoptosis assays (Annexin V and TUNEL), viability assays (MTT), and clonogenic survival assays. The changes along MAPK (p44/p42)/JNK/p38-MAPK signal transduction pathways were then investigated using quantitative Western analysis with phospho-specific antibodies to determine the molecular mechanisms by which C225 mediates a given response. Results: C225 clearly enhanced radiation response for 7 of the 12 primary glioma cell lines studied. Enhancement of both immediate and delayed apoptotic responses was evident in these 7 responsive cell lines after C225 administration. The average apoptosis index at 6 hours post-RT+C225 for the 7 responsive lines was 9.5%, compared to 1.2% for the RT-only controls. A pattern of delayed apoptosis was evident in these 7 lines, with secondary apoptotic peaks (∼ 8.0%) occurring at 24 hours post-RT+C225. Time course viability measurements revealed a steady decrease in viable tumor cells in these responsive cell lines from 75% at 6 hours post-RT+C225 to 20% at 7 days. Clonogenic survival was also diminished in these 7 lines

  16. Individualized therapies in colorectal cancer: KRAS as a marker for response to EGFR-targeted therapy

    Directory of Open Access Journals (Sweden)

    Li Kuiyuan

    2009-04-01

    Full Text Available Abstract Individualized therapies that are tailored to a patient's genetic composition will be of tremendous value for treatment of cancer. Recently, Kirsten ras (KRAS status has emerged as a predictor of response to epidermal growth factor receptor (EGFR targeted therapies. In this article, we will discuss targeted therapies for colorectal cancers (CRC based on EGFR signaling pathway and review published data about the potential usefulness of KRAS as a biological marker for response to these therapies. Results from relevant studies published since 2005 and unpublished results presented at national meetings were retrieved and summarized. These studies reflected response (or lack of response to EGFR-targeted therapies in patients with metastatic CRC as a function of KRAS status. It has become clear that patients with colorectal cancer whose tumor has an activating mutation in KRAS do not respond to monoclonal antibody therapies targeting EGFR. It should now become a standard practice that any patients being considered for EGFR targeted therapies have their tumors tested for KRAS status and only those with wild-type KRAS being offered such therapies.

  17. 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%.

  18. Discovery of novel EGFR tyrosine kinase inhibitors by structure-based virtual screening.

    Science.gov (United States)

    Li, Siyuan; Sun, Xianqiang; Zhao, Hongli; Tang, Yun; Lan, Minbo

    2012-06-15

    By using of structure-based virtual screening, 13 novel epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors were discovered from 197,116 compounds in the SPECS database here. Among them, 8 compounds significantly inhibited EGFR kinase activity with IC(50) values lower than 10 μM. 3-{[1-(3-Chloro-4-fluorophenyl)-3,5-dioxo-4-pyrazolidinylidene]methyl}phenyl 2-thiophenecarboxylate (13), particularly, was the most potent inhibitor possessing the IC(50) value of 3.5 μM. The docking studies also provide some useful information that the docking models of the 13 compounds are beneficial to find a new path for designing novel EGFR inhibitors. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. [Study on the correlation between EGFR-STAT3 signal pathway and laryngeal papilloma].

    Science.gov (United States)

    Wang, Xinhua; Sun, Jingwu

    2009-09-01

    To explore the relationship between the expression of EGFR and STAT3 in human laryngeal papilloma and its biological behavior. Reverse transcription polymerase chain reaction(RT-PCR), immunohistochemical staining and Western blot were used to evaluate the mRNA and protein expression of EGFR and STAT3 (p-STAT3) in 42 laryngeal papilloma tissues and 15 samples of normal laryngeal tissue, and the relationship between the protein expression of them and clinic pathological parameters was also analyzed. The mRNA expression levels of EGFR and STAT3 in laryngeal papilloma tissue were significantly higher than that in normal laryngeal tissue (P papilloma than normal laryngeal tissue by immunohistochemistry and western blot (P papilloma (P papilloma (P papilloma,, and the persistent activation of STAT3 gene plays an important role in the recurrence and canceration of laryngeal papilloma.

  20. Increased Epidermal Growth Factor Receptor (EGFR Associated with Hepatocyte Growth Factor (HGF and Symptom Severity in Children with Autism Spectrum Disorders (ASDs

    Directory of Open Access Journals (Sweden)

    Anthony J. Russo

    2014-01-01

    Full Text Available Background One in 88 children in the US is thought to have one of the autism spectrum disorders (ASDs. ASDs are characterized by social impairments and communication problems. Growth factors and their receptors may play a role in the etiology of ASDs. Research has shown that epidermal growth factor receptor (EGFR activation is associated with nerve cell development and repair. This study was designed to measure plasma levels of EGFR in autistic children and correlate these levels with its ligand, epidermal growth factor, other related putative biomarkers such as hepatocyte growth factor (HGF, the ligand for MET (MNNG HOS transforming gene receptor, as well as the symptom severity of 19 different behavioral symptoms. Subjects and Methods Plasma EGFR concentration was measured in 33 autistic children and 34 age- and gender-similar neurotypical controls, using an enzyme-linked immunosorbent assay. Plasma EGFR levels were compared to putative biomarkers known to be associated with EGFR and MET and severity levels of 19 autism-related symptoms. Results We found plasma EGFR levels significantly higher in autistic children, when compared to neurotypical controls. EGFR levels correlated with HGF and high-mobility group protein B1 (HMGB1 levels, but not other tested putative biomarkers, and EGFR levels correlated significantly with severity of expressive language, conversational language, focus/attention, hyperactivity, eye contact, and sound sensitivity deficiencies. Conclusions These results suggest a relationship between increased plasma EGFR levels and designated symptom severity in autistic children. A strong correlation between plasma EGFR and HGF and HMGB1 suggests that increased EGFR levels may be associated with the HGF/Met signaling pathway, as well as inflammation.

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

    Science.gov (United States)

    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.

  2. Epidermal growth factor receptor (EGFR mutations and expression in squamous cell carcinoma of the esophagus in central Asia

    Directory of Open Access Journals (Sweden)

    Abedi-Ardekani Behnoush

    2012-12-01

    Full Text Available Abstract Background Esophageal squamous cell carcinoma (ESCC shows geographic variations in incidence, with high incidences (>50/105 person-years in central Asia, including North Eastern Iran (Golestan and Northern India (Kashmir. In contrast to Western countries, smoking does not appear to be a significant risk factor for ESCC in central Asia. In lung adenocarcinoma, activating mutations in the gene encoding epidermal growth factor receptor (EGFR are frequent in tumors of never smokers of Asian origin, predicting therapeutic sensitivity to Egfr-targeting drugs. Methods In this study 152 cases of histologically confirmed ESCC from Iran (Tehran and Golestan Province and North India (Kashmir Valley have been analyzed for EGFR mutation by direct sequencing of exons 18–21. Egfr protein expression was evaluated by immunohistochemistry in 34 samples from Tehran and HER2 mutations were analyzed in 54 cases from Kashmir. Results A total of 14 (9.2% EGFR variations were detected, including seven variations in exons. Among those, four (2.6% were already documented in lung cancers, two were reported as polymorphisms and one was a potentially new activating mutation. All but one variation in introns were previously identified as polymorphisms. Over-expression of Egfr was detected in 22/34 (65% of tested cases whereas no HER2 mutation was found in 54 cases from Kashmir. Conclusion Overall, EGFR mutations appear to be a rare event in ESCC in high incidence areas of central Asia, although a very small proportion of cases may harbor mutations predicting sensitivity to anti-Egfr drugs.

  3. Analysis of EGFR, HER2, and TOP2A gene status and chromosomal polysomy in gastric adenocarcinoma from Chinese patients

    International Nuclear Information System (INIS)

    Liang, Zhiyong; Zeng, Xuan; Gao, Jie; Wu, Shafei; Wang, Peng; Shi, Xiaohua; Zhang, Jing; Liu, Tonghua

    2008-01-01

    The EGFR and HER2 genes are located on chromosomes 7 and 17, respectively. They are therapeutic targets in some tumors. The TOP2A gene, which is located near HER2 on chromosome 17, is the target of many chemotherapeutic agents, and co-amplification of HER2 and TOP2A has been described in several tumor types. Herein, we investigated the gene status of EGFR, HER2, and TOP2A in Chinese gastric carcinoma patients. We determined the rate of polysomy for chromosomes 7 and 17, and we attempted to clarify the relationship between EGFR, HER2, and TOP2A gene copy number and increased expression of their encoded proteins. Furthermore, we tried to address the relationship between alterations in EGFR, HER2, and TOP2A and chromosome polysomy. One hundred cases of formalin fixed and paraffin embedded tumor tissues from Chinese gastric carcinoma patients were investigated by immunohistochemistry and fluorescence in situ hybridization (FISH) methods. Forty-two percent of the cases showed EGFR overexpression; 16% showed EGFR FISH positive; 6% showed HER2 overexpression; and 11% showed HER2 gene amplification, including all six HER2 overexpression cases. TOP2A nuclear staining (nuclear index, NI) was determined in all 100 tumors: NI values ranged from 0.5 – 90%. Three percent of the tumors showed TOP2A gene amplification, which were all accompanied by HER2 gene amplification. Nineteen percent of the tumors showed chromosome 7 polysomy, and 16% showed chromosome 17 polysomy. Chromosome 7 polysomy correlated significantly with EGFR FISH-positivity, but was not associated with EGFR overexpression. HER2 overexpression associated significantly with HER2 gene amplification. TOP2A gene amplification was significantly associated with HER2 gene amplification. No relationship was found between alterations in the EGFR, HER2, and TOP2A genes and clinicopathologic variables of gastric carcinoma. The data from our study suggest that chromosome 7 polysomy may be responsible for increased EGFR

  4. Estimating quality adjusted progression free survival of first-line treatments for EGFR mutation positive non small cell lung cancer patients in The Netherlands

    Directory of Open Access Journals (Sweden)

    Verduyn S

    2012-09-01

    Full Text Available Abstract Background Gefitinib, a tyrosine kinase inhibitor, is an effective treatment in advanced non-small cell lung cancer (NSCLC patients with an activating mutation in the epidermal growth factor receptor (EGFR. Randomised clinical trials showed a benefit in progression free survival for gefitinib versus doublet chemotherapy regimens in patients with an activated EGFR mutation (EGFR M+. From a patient perspective, progression free survival is important, but so is health-related quality of life. Therefore, this analysis evaluates the Quality Adjusted progression free survival of gefitinib versus three relevant doublet chemotherapies (gemcitabine/cisplatin (Gem/Cis; pemetrexed/cisplatin (Pem/Cis; paclitaxel/carboplatin (Pac/Carb in a Dutch health care setting in patients with EGFR M+ stage IIIB/IV NSCLC. This study uses progression free survival rather than overall survival for its time frame in order to better compare the treatments and to account for the influence that subsequent treatment lines would have on overall survival analysis. Methods Mean progression free survival for Pac/Carb was obtained by extrapolating the median progression free survival as reported in the Iressa-Pan-Asia Study (IPASS. Data from a network meta-analysis was used to estimate the mean progression free survival for therapies of interest relative to Pac/Carb. Adjustment for health-related quality of life was done by incorporating utilities for the Dutch population, obtained by converting FACT-L data (from IPASS to utility values and multiplying these with the mean progression free survival for each treatment arm to determine the Quality Adjusted progression free survival. Probabilistic sensitivity analysis was carried out to determine 95% credibility intervals. Results The Quality Adjusted progression free survival (PFS (mean, (95% credibility interval was 5.2 months (4.5; 5.8 for Gem/Cis, 5.3 months (4.6; 6.1 for Pem/Cis; 4.9 months (4.4; 5.5 for Pac/Carb and 8

  5. Effect of Genetic African Ancestry on eGFR and Kidney Disease

    Science.gov (United States)

    Nadkarni, Girish N.; Belbin, Gillian; Lotay, Vaneet; Wyatt, Christina; Gottesman, Omri; Bottinger, Erwin P.; Kenny, Eimear E.; Peter, Inga

    2015-01-01

    Self-reported ancestry, genetically determined ancestry, and APOL1 polymorphisms are associated with variation in kidney function and related disease risk, but the relative importance of these factors remains unclear. We estimated the global proportion of African ancestry for 9048 individuals at Mount Sinai Medical Center in Manhattan (3189 African Americans, 1721 European Americans, and 4138 Hispanic/Latino Americans by self-report) using genome-wide genotype data. CKD-EPI eGFR and genotypes of three APOL1 coding variants were available. In admixed African Americans and Hispanic/Latino Americans, serum creatinine values increased as African ancestry increased (per 10% increase in African ancestry, creatinine values increased 1% in African Americans and 0.9% in Hispanic/Latino Americans; P≤1x10−7). eGFR was likewise significantly associated with African genetic ancestry in both populations. In contrast, APOL1 risk haplotypes were significantly associated with CKD, eGFRblack on the basis of ≥50% African ancestry resulted in higher eGFR for 14.7% of Hispanic/Latino Americans and lower eGFR for 4.1% of African Americans, affecting CKD staging in 4.3% and 1% of participants, respectively. Reclassified individuals had electrolyte values consistent with their newly assigned CKD stage. In summary, proportion of African ancestry was significantly associated with normal-range creatinine and eGFR, whereas APOL1 risk haplotypes drove the associations with CKD. Recalculation of eGFR on the basis of genetic ancestry affected CKD staging and warrants additional investigation. PMID:25349204

  6. Efficacy of Icotinib for Advanced Non-small Cell Lung Cancer Patients with EGFR Status Identified

    Directory of Open Access Journals (Sweden)

    Yiping ZHANG

    2013-03-01

    Full Text Available Background and objective As the first epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI in China, icotinib shows promising anticancer activity in vitro and vivo. The phase III clinical study (ICOGEN showed that icotinib has a good efficacy and tolerability in Chinese patients with advanced non-small cell lung cancer (NSCLC compared with gefitinib. This retrospective study aims to evaluate the efficacy and tolerability of icotinib monotherapy for advanced NSCLC patients with EGFR mutation and wild-type patients in our hospital. Methods Patients with advanced NSCLC who were treated with icotinib in Zhejiang Cancer Hospital were retrospectively analyzed from August, 2011 to August, 2012. Survival was estimated using Kaplan-Meier analysis and Log-rank tests. Results The clinical data of 49 patients (13 with wild-type and 36 with EGFR mutation with NSCLC were enrolled in the current study. The patients’ overall objective response rate (ORR was 58.3% and the disease control rate (DCR in 36 EGFR mutation patients was 88.9%. The ORR was 7.7% and DCR was 53.8% in the wild-type patients. Median progression-free survival (PFS with icotinib treatment in EGFR mutation patients was 9.5 months and 2.2 months in wild-type patients (P<0.001. Nineteen patients with EGFR mutation received icotinib as first-line and 17 in further-line treatment. The PFS was 9.5 months in the first-line and 8.5 months for second-line or further-line patients (P=0.41. Median overall survival (OS in EGFR mutation patients was not reached, but was 12.6 months in wild-type patients. Most of the drug-related adverse events were mild (grade I or II and reversible with no grade IV toxicity. Conclusion Icotinib monotherapy showed significant antitumor activity in advanced NSCLC EGFR mutation patients. The toxicity was well tolerated and acceptable.

  7. A bi-paratopic anti-EGFR nanobody efficiently inhibits solid tumour growth

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    Roovers, Rob C.; Vosjan, Maria J.W.D.; Laeremans, Toon; el Khoulati, Rachid; de Bruin, Renée C.G.; Ferguson, Kathryn M.; Verkleij, Arie J.; van Dongen, Guus A.M.S.; van Bergen en Henegouwen, Paul M. P.

    2014-01-01

    The epidermal growth factor receptor (EGFR) has been shown to be a valid cancer target for antibody-based therapy. At present, several anti-EGFR monoclonal antibodies (mAbs) have been successfully used, among which cetuximab and matuzumab. X-ray crystallography data show that these antibodies bind to different epitopes on the ecto-domain of EGFR, providing a rationale for the combined use of these two antibody specificities. We have previously reported on the successful isolation of antagonistic anti-EGFR nanobodies. In the present study, we aimed to improve on these molecules by combining nanobodies with specificities similar to both cetuximab and matuzumab into a single bi-paratopic molecule. Carefully designed phage nanobody selections resulted in two sets of nanobodies that specifically blocked the binding of either matuzumab or of cetuximab to EGFR and that did not compete for each others binding. A combination of nanobodies from both epitope groups into the bi-paratopic nanobody CONAN-1 was shown to block EGFR activation more efficiently than monovalent or bivalent (monospecific) nanobodies. In addition, this bi-paratopic nanobody potently inhibited EGF-dependent cell proliferation. Importantly, in an in vivo model of athymic mice bearing A431 xenografts, CONAN-1 inhibited tumour outgrowth with an almost similar potency as the whole mAb cetuximab, despite the fact that CONAN-1 is devoid of an Fc portion that could mediate immune effector functions. Compared to therapy using bivalent, mono-specific nanobodies, CONAN-1 was clearly more potent in tumour growth inhibition. These results show that the rational design of bi-paratopic nanobody-based anti-cancer therapeutics may yield potent lead molecules for further development. PMID:21520037

  8. Upregulation of HLA Class I Expression on Tumor Cells by the Anti-EGFR Antibody Nimotuzumab

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    Greta Garrido

    2017-10-01

    Full Text Available Defining how epidermal growth factor receptor (EGFR-targeting therapies influence the immune response is essential to increase their clinical efficacy. A growing emphasis is being placed on immune regulator genes that govern tumor – T cell interactions. Previous studies showed an increase in HLA class I cell surface expression in tumor cell lines treated with anti-EGFR agents. In particular, earlier studies of the anti-EGFR blocking antibody cetuximab, have suggested that increased tumor expression of HLA class I is associated with positive clinical response. We investigated the effect of another commercially available anti-EGFR antibody nimotuzumab on HLA class I expression in tumor cell lines. We observed, for the first time, that nimotuzumab increases HLA class I expression and its effect is associated with a coordinated increase in mRNA levels of the principal antigen processing and presentation components. Moreover, using 7A7 (a specific surrogate antibody against murine EGFR, we obtained results suggesting the importance of the increased MHC-I expression induced by EGFR-targeted therapies display higher in antitumor immune response. 7A7 therapy induced upregulation of tumor MHC-I expression in vivo and tumors treated with this antibody display higher susceptibility to CD8+ T cells-mediated lysis. Our results represent the first evidence suggesting the importance of the adaptive immunity in nimotuzumab-mediated antitumor activity. More experiments should be conducted in order to elucidate the relevance of this mechanism in cancer patients. This novel immune-related antitumor mechanism mediated by nimotuzumab opens new perspectives for its combination with various immunotherapeutic agents and cancer vaccines.

  9. Long-term treatment with EGFR inhibitor erlotinib attenuates renal inflammatory cytokines but not nephropathy in Alport syndrome mouse model.

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    Omachi, Kohei; Miyakita, Rui; Fukuda, Ryosuke; Kai, Yukari; Suico, Mary Ann; Yokota, Tsubasa; Kamura, Misato; Shuto, Tsuyoshi; Kai, Hirofumi

    2017-12-01

    Alport syndrome (AS) is a hereditary kidney disease caused by mutation of type IV collagen. Loss of collagen network induces collapse of glomerular basement membrane (GBM) structure. The previous studies showed that upregulation of some tyrosine kinase receptors signaling accompanied GBM disorder in AS mouse model. EGFR signaling is one of the well-known receptor kinase signaling that is involved in glomerular diseases. However, whether EGFR signaling is relevant to AS progression is still uninvestigated. Here, we determined the involvement of EGFR in AS and the effect of suppressing EGFR signaling by erlotinib treatment on AS progression. Phosphorylated EGFR expression was investigated by Western blotting analysis and immunostaining of kidney tissues of Col4a5 mutant mice (a mouse model of X-linked AS). To check the effect of blocking EGFR signaling in AS, we administered erlotinib to AS mice once a day (10 mg/kg/day) orally for 18 weeks. Renal function parameters (proteinuria, serum creatinine, and BUN) and renal histology were assessed, and the gene expressions of inflammatory cytokines were analyzed in renal tissues. Phosphorylated EGFR expression was upregulated in AS mice kidney tissues. Erlotinib slightly reduced the urinary protein and suppressed the expression of renal injury markers (Lcn2, Lysozyme) and inflammatory cytokines (Il-6, Il-1β and KC). Erlotinib did not improve renal pathology, such as glomerular sclerosis and fibrosis. These findings suggest that EGFR signaling is upregulated in kidney, but although inhibiting this signaling pathway suppressed renal inflammatory cytokines, it did not ameliorate renal dysfunction in AS mouse model.

  10. EGFR and HER2 expression in primary cervical cancers and corresponding lymph node metastases: Implications for targeted radiotherapy

    International Nuclear Information System (INIS)

    Shen, Li; Shui, Yongjie; Wang, Xiaojia; Sheng, Liming; Yang, Zhengyan; Xue, Danfeng; Wei, Qichun

    2008-01-01

    Proteins overexpressed on the surface of tumor cells can be selectively targeted. Epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) are among the most often targeted proteins. The level and stability of expression in both primary tumors and corresponding metastases is crucial in the assessment of a receptor as target for imaging in nuclear medicine and for various forms of therapy. So far, the expression of EGFR and HER2 has only been determined in primary cervical cancers, and we have not found published data regarding the receptor status in corresponding metastatic lesions. The goal of this study was to evaluate whether any of these receptors are suitable as target for clinical diagnosis and therapy. Expression of EGFR and HER2 was investigated immunohistochemically in both lymph node metastases and corresponding primary cervical cancers (n = 53). HER2 and EGFR expression was scored using HercepTest criteria (0, 1+, 2+ or 3+). EGFR overexpression (2+ or 3+) was found in 64% (35/53) of the primary cervical tumors and 60% (32/53) of the corresponding lymph node metastases. There was a good concordance between the primary tumors and the paired metastases regarding EGFR expression. Only four patients who had 2+ or 3+ in the primary tumors changed to 0 or 1+ in lymph node metastases, and another two cases changed the other way around. None of the primary tumors or the lymph node metastases expressed HER2 protein. The EGFR expression seems to be common and stable during cervical cancer metastasis, which is encouraging for testing of EGFR targeted radiotherapy. HER2 appears to be of poor interest as a potential target in the treatment of cervical cancer

  11. Cellular and Tumor Radiosensitivity is Correlated to Epidermal Growth Factor Receptor Protein Expression Level in Tumors Without EGFR Amplification

    International Nuclear Information System (INIS)

    Kasten-Pisula, Ulla; Saker, Jarob; Eicheler, Wolfgang; Krause, Mechthild; Yaromina, Ala; Meyer-Staeckling, Soenke; Scherkl, Benjamin; Kriegs, Malte; Brandt, Burkhard; Grenman, Reidar; Petersen, Cordula; Baumann, Michael; Dikomey, Ekkehard

    2011-01-01

    Purpose: There is conflicting evidence for whether the expression of epidermal growth factor receptor in human tumors can be used as a marker of radioresponse. Therefore, this association was studied in a systematic manner using squamous cell carcinoma (SCC) cell lines grown as cell cultures and xenografts. Methods and Materials: The study was performed with 24 tumor cell lines of different tumor types, including 10 SCC lines, which were also investigated as xenografts on nude mice. Egfr gene dose and the length of CA-repeats in intron 1 were determined by polymerase chain reaction, protein expression in vitro by Western blot and in vivo by enzyme-linked immunosorbent assay, and radiosensitivity in vitro by colony formation. Data were correlated with previously published tumor control dose 50% data after fractionated irradiation of xenografts of the 10 SCC. Results: EGFR protein expression varies considerably, with most tumor cell lines showing moderate and only few showing pronounced upregulation. EGFR upregulation could only be attributed to massive gene amplification in the latter. In the case of little or no amplification, in vitro EGFR expression correlated with both cellular and tumor radioresponse. In vivo EGFR expression did not show this correlation. Conclusions: Local tumor control after the fractionated irradiation of tumors with little or no gene amplification seems to be dependent on in vitro EGFR via its effect on cellular radiosensitivity.

  12. EPIDERMAL GROWTH FACTOR RECEPTOR (EGFR AND HUMAN PAPILLOMAVIRUS (HPV L1 CAPSID PROTEIN IN CERVICAL SQUAMOUS INTRAEPITHELIAL LESIONS

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    Balan Raluca

    2010-09-01

    Full Text Available We analyzed the immunohistochemical pattern of epidermal growth factor receptor (EGFR in cervical squamous intraepithelial lesions (SILs in correlation with L1 HPV capsid protein, in order to determine the relationship between EGFR expression and the infection status of human papillomavirus (HPV. The study included 40 cases, 24 LSIL (low grade SIL (CIN1, cervical intraepithelial neoplasia and 16 HSIL (high grade SIL (6 cases of CIN2 and 10 cases of CIN3. The immunoexpression of L1 HPV protein was assessed on conventional cervico-vaginal smears and EGFR was immunohistochemically evaluated on the corresponding cervical biopsies. The HPV L1 capsid protein was expressed in 45.83% of LSIL and 25% of HSIL. EGFR was overexpressed in 62,4% of HSIL (58,4% CIN2 and 41,6% CIN3 and 37,6% LSIL. The immunoexpression of L1 HPV has clinical application in the progression assessment of the cervical precancerous lesions without a correlation to the grade of the cervical SIL. EGFR is expressed by all proliferating squamous epithelial cells, thus corresponding with the grade of SIL. The evaluation of EGFR status, correlated with L1 HPV protein expression, can provide useful data of progression risk of cervical squamous intraepithelial lesions

  13. Serum bilirubin concentration is associated with eGFR and urinary albumin excretion in patients with type 1 diabetes mellitus.

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    Nishimura, Takeshi; Tanaka, Masami; Sekioka, Risa; Itoh, Hiroshi

    2015-01-01

    Although relationships of serum bilirubin concentration with estimated glomerular filtration rate (eGFR) and urinary albumin excretion (UAE) in patients with type 2 diabetes have been reported, whether such relationships exist in patients with type 1 diabetes is unknown. A total of 123 patients with type 1 diabetes were investigated in this cross-sectional study. The relationship between bilirubin (total and indirect) concentrations and log(UAE) as well as eGFR was examined by Pearson's correlation analyses. Multivariate regression analyses were used to assess the association of bilirubin (total and indirect) with eGFR as well as log(UAE). A positive correlation was found between serum bilirubin concentration and eGFR; total bilirubin (r=0.223, p=0.013), indirect bilirubin (r=0.244, p=0.007). A negative correlation was found between serum bilirubin concentration and log(UAE); total bilirubin (r=-0.258, p=0.005), indirect bilirubin (r=-0.271, p=0.003). Multivariate regression analyses showed that indirect bilirubin concentration was an independent determinant of eGFR and log(UAE). Bilirubin concentration is associated with both eGFR and log(UAE) in patients with type 1 diabetes. Bilirubin might have a protective role in the progression of type 1 diabetic nephropathy. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. [Clinical Observation of Icotinib Hydrochloride for Advanced Non-small Cell Lung Cancer Patients with EGFR Status Identified].

    Science.gov (United States)

    Li, Xi; Qin, Na; Wang, Jinghui; Yang, Xinjie; Zhang, Xinyong; Lv, Jialin; Wu, Yuhua; Zhang, Hui; Nong, Jingying; Zhang, Quan; Zhang, Shucai

    2015-12-01

    Icotinib is the first self-developed small molecular drug in China for targeted therapy of lung cancer. Compared to the other two commercially available epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors, gefitinib and erlotinib, icotinib is similar to them in chemical structure, mechanism of activity and therapeutic effects. To explore the efficacy and side effects of icotinib hydrochloride in the treatment of the advanced non-small cell lung cancer (NSCLC) patients with EGFR mutation and wild-type. Patients with advanced NSCLC who were treated with icotinib hydrochloride in Beijing Chest Hospital were retrospective analyzed from March 2009 to December 2014. The clinical data of 124 patients (99 with EGFR mutation and 25 with wild type) with advanced NSCLC were enrolled in this study. The patients' overall objective response rate (ORR) was 51.6 % and the disease control rate (DCR) was 79.8%; The patients with EGFR mutation, ORR was 63.6%, DCR was 93.9%. The ORR was 4.0% and the DCR was 24.0% in the wild-type patients. Median progression-free survival (PFS) with icotinib treatment in EGFR mutation patients was 10.5 months and 1.0 month in wild-type patients. The major adverse events were mild skin rash (30.6%) and diarrhea (16.1%). Monotherapy with icotinib hydrochloride is effective and tolerable for the advanced NSCLC EGFR mutation patients.


  15. Clinical Observation of Icotinib Hydrochloride for Advanced Non-small Cell Lung Cancer Patients with EGFR Status Identified

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    Xi LI

    2015-12-01

    Full Text Available Background and objective Icotinib is the first self-developed small molecular drug in China for targeted therapy of lung cancer. Compared to the other two commercially available epidermal growth factor receptor (EGFR tyrosine kinase inhibitors, gefitinib and erlotinib, icotinib is similar to them in chemical structure, mechanism of activity and therapeutic effects. To explore the efficacy and side effects of icotinib hydrochloride in the treatment of the advanced non-small cell lung cancer (NSCLC patients with EGFR mutation and wild-type. Methods Patients with advanced NSCLC who were treated with icotinib hydrochloride in Beijing Chest Hospital were retrospective analyzed from March 2009 to December 2014. Results The clinical data of 124 patients (99 with EGFR mutation and 25 with wild type with advanced NSCLC were enrolled in this study. The patients’ overall objective response rate (ORR was 51.6 % and the disease control rate (DCR was 79.8%; The patients with EGFR mutation, ORR was 63.6%, DCR was 93.9%. The ORR was 4.0% and the DCR was 24.0% in the wild-type patients. Median progression-free survival (PFS with icotinib treatment in EGFR mutation patients was 10.5 months and 1.0 month in wild-type patients. The major adverse events were mild skin rash (30.6% and diarrhea (16.1%. Conclusion Monotherapy with icotinib hydrochloride is effective and tolerable for the advanced NSCLC EGFR mutation patients.

  16. Targeting TORC1/2 Enhances Sensitivity to EGFR Inhibitors in Head and Neck Cancer Preclinical Models

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    Andre Cassell

    2012-11-01

    Full Text Available Head and neck squamous cell carcinoma (HNSCC is characterized by overexpression of the epidermal growth factor receptor (EGFR where treatments targeting EGFR have met with limited clinical success. Elucidation of the key downstream-pathways that remain activated in the setting of EGFR blockade may reveal new therapeutic targets. The present study was undertaken to test the hypothesis that inhibition of the mammalian target of rapamycin (mTOR complex would enhance the effects of EGFR blockade in HNSCC preclinical models. Treatment of HNSCC cell lines with the newly developed TORC1/TORC2 inhibitor OSI-027/ASP4876 resulted in dose-dependent inhibition of proliferation with abrogation of phosphorylation of known downstream targets including phospho-AKT (Ser473, phospho-4E-BP1, phospho-p70s6K, and phospho-PRAS40. Furthermore, combined treatment with OSI-027 and erlotinib resulted in enhanced biochemical effects and synergistic growth inhibition in vitro. Treatment of mice bearing HNSCC xenografts with a combination of the Food and Drug Administration (FDA-approved EGFR inhibitor cetuximab and OSI-027 demonstrated a significant reduction of tumor volumes compared with either treatment alone. These findings suggest that TORC1/TORC2 inhibition in conjunction with EGFR blockade represents a plausible therapeutic strategy for HNSCC.

  17. Sex-specific incidence of EGFR mutation and its association with age and obesity in lung adenocarcinomas: a retrospective analysis.

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    Kim, Hye-Ryoun; Kim, Seo Yun; Kim, Cheol Hyeon; Yang, Sung Hyun; Lee, Jae Cheol; Choi, Chang-Min; Na, Im Il

    2017-11-01

    Age and obesity are well-known risk factors for various cancers, but the potential roles of age and obesity in lung cancer, especially in those with activating EGFR mutations, have not been thoroughly evaluated. The aim of this retrospective study is to evaluate the associations between the sex-specific incidence of EGFR mutations and age and obesity. We conducted a retrospective study based on the data from 1378 lung adenocarcinoma cases. The degree of obesity was categorized by body mass index (BMI). The associations between EGFR mutational status and clinical factors, including stage, smoking history, age group (≤45 years, 46-55, 56-65 and >65), and BMI group (obesity (adjusted OR for BMI group = 1.23, p-trend = 0.04). In contrast, in women, the incidence of EGFR mutation was positively associated with age (adjusted OR for age group = 1.19, p-trend = 0.02). However, the incidence of EGFR mutation was not statistically associated with obesity (adjusted OR for BMI group = 1.03, p-trend = 0.76). Our data suggests that age and obesity may contribute to the sex-specific incidence of EGFR mutation in lung adenocarcinoma in different manners.

  18. Targeting TORC1/2 enhances sensitivity to EGFR inhibitors in head and neck cancer preclinical models.

    Science.gov (United States)

    Cassell, Andre; Freilino, Maria L; Lee, Jessica; Barr, Sharon; Wang, Lin; Panahandeh, Mary C; Thomas, Sufi M; Grandis, Jennifer R

    2012-11-01

    Head and neck squamous cell carcinoma (HNSCC) is characterized by overexpression of the epidermal growth factor receptor (EGFR) where treatments targeting EGFR have met with limited clinical success. Elucidation of the key downstream-pathways that remain activated in the setting of EGFR blockade may reveal new therapeutic targets. The present study was undertaken to test the hypothesis that inhibition of the mammalian target of rapamycin (mTOR) complex would enhance the effects of EGFR blockade in HNSCC preclinical models. Treatment of HNSCC cell lines with the newly developed TORC1/TORC2 inhibitor OSI-027/ASP4876 resulted in dose-dependent inhibition of proliferation with abrogation of phosphorylation of known downstream targets including phospho-AKT (Ser473), phospho-4E-BP1, phospho-p70s6K, and phospho-PRAS40. Furthermore, combined treatment with OSI-027 and erlotinib resulted in enhanced biochemical effects and synergistic growth inhibition in vitro. Treatment of mice bearing HNSCC xenografts with a combination of the Food and Drug Administration (FDA)-approved EGFR inhibitor cetuximab and OSI-027 demonstrated a significant reduction of tumor volumes compared with either treatment alone. These findings suggest that TORC1/TORC2 inhibition in conjunction with EGFR blockade represents a plausible therapeutic strategy for HNSCC.

  19. Targeting TORC1/2 Enhances Sensitivity to EGFR Inhibitors in Head and Neck Cancer Preclinical Models1

    Science.gov (United States)

    Cassell, Andre; Freilino, Maria L; Lee, Jessica; Barr, Sharon; Wang, Lin; Panahandeh, Mary C; Thomas, Sufi M; Grandis, Jennifer R

    2012-01-01

    Head and neck squamous cell carcinoma (HNSCC) is characterized by overexpression of the epidermal growth factor receptor (EGFR) where treatments targeting EGFR have met with limited clinical success. Elucidation of the key downstream-pathways that remain activated in the setting of EGFR blockade may reveal new therapeutic targets. The present study was undertaken to test the hypothesis that inhibition of the mammalian target of rapamycin (mTOR) complex would enhance the effects of EGFR blockade in HNSCC preclinical models. Treatment of HNSCC cell lines with the newly developed TORC1/TORC2 inhibitor OSI-027/ASP4876 resulted in dose-dependent inhibition of proliferation with abrogation of phosphorylation of known downstream targets including phospho-AKT (Ser473), phospho-4E-BP1, phospho-p70s6K, and phospho-PRAS40. Furthermore, combined treatment with OSI-027 and erlotinib resulted in enhanced biochemical effects and synergistic growth inhibition in vitro. Treatment of mice bearing HNSCC xenografts with a combination of the Food and Drug Administration (FDA)-approved EGFR inhibitor cetuximab and OSI-027 demonstrated a significant reduction of tumor volumes compared with either treatment alone. These findings suggest that TORC1/TORC2 inhibition in conjunction with EGFR blockade represents a plausible therapeutic strategy for HNSCC. PMID:23226094

  20. Prognostic and predictive values of EGFR overexpression and EGFR copy number alteration in HER2-positive breast cancer.

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    Lee, H J; Seo, A N; Kim, E J; Jang, M H; Kim, Y J; Kim, J H; Kim, S-W; Ryu, H S; Park, I A; Im, S-A; Gong, G; Jung, K H; Kim, H J; Park, S Y

    2015-01-06

    Epidermal growth factor receptor (EGFR) is overexpressed in a subset of human epidermal growth factor receptor 2 (HER2)-positive breast cancers, and coexpression of HER2 and EGFR has been reported to be associated with poor clinical outcome. Moreover, interaction between HER2 and EGFR has been suggested to be a possible basis for trastuzumab resistance. We analysed the clinical significance of EGFR overexpression and EGFR gene copy number alterations in 242 HER2-positive primary breast cancers. In addition, we examined the correlations between EGFR overexpression, trastuzumab response and clinical outcome in 447 primary, and 112 metastatic HER2-positive breast cancer patients treated by trastuzumab. Of the 242 primary cases, the level of EGFR overexpression was 2+ in 12.7% and 3+ in 11.8%. High EGFR gene copy number was detected in 10.3%. Epidermal growth factor receptor overexpression was associated with hormone receptor negativity and high Ki-67 proliferation index. In survival analyses, EGFR overexpression, but not high EGFR copy number, was associated with poor disease-free survival in all patients, and in the subgroup not receiving adjuvant trastuzumab. In 447 HER2-positive primary breast cancer patients treated with adjuvant trastuzumab, EGFR overexpression was also an independent poor prognostic factor. However, EGFR overexpression was not associated with trastuzumab response, progression-free survival or overall survival in the metastatic setting. Epidermal growth factor receptor overexpression, but not high EGFR copy number, is a poor prognostic factor in HER2-positive primary breast cancer. Epidermal growth factor receptor overexpression is a predictive factor for trastuzumab response in HER2-positive primary breast cancer, but not in metastatic breast cancer.

  1. Metaplastic Breast Cancer and EGFR Expression

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    Nilufer Avci

    2014-03-01

    Full Text Available Aim: Metaplastic breast cancer has poor prognosis and is usually triple negative. Although it is morphologically more heterogeneous than triple negative breast cancers, expression profile is more homogeneous. In this study, we investigated our metaplastic breast cancer cases regarding their pathology and clinical characteristics. Material and Method: 16 metaplastic breast cancer cases from four different center were included in the study. Pathology and clinical characteristics of the cases were evaluated retrospectively. Results: All the cases are female and median age is 48 (39-45. Tumor is commonly localized to the outer quadrant and mean diameter of the mass is 37.5 (15-100 mm. Tumor diameter is ≤20 mm in 3 (15.8%, >20-≤50 mm in 11 (57.9% and >50 mm in 3 (10.51% of the cases. Only 4 (16.1% patients have axillary lymph node involvement. When considering histological subtypes, five of the cases has squamous cell, five of them has spindle cell, one of them has mucoepidermoid, and in five cases the subtype was not identified. Considering hormone receptor status ER and PR was negative in 78.9%, 63.2% respectively. HER2 protein expression was positive by immunohistochemical staining in 1 (5.3% case. CK5/6 and CK17 was both positive in 7 (36.8% cases. EGFR expression was positive in 4 (21.1% cases, was negative in 5 (26.3% cases and not identified in 7 (36.8% cases. Three of the cases were offered neoadjuvant chemotherapy. As neoadjuvant chemotherapy, anthracycline and taxane combination (n:2 TAC, n:1 AC-paclitaxel was preferred. Mean follow-up was 41 months. Mean survival was 42.4 months in EGFR negative patients and 47.5 months in EGFR positive patients. This difference was not statistically significant. During follow-up 3 cases had recurrence. Discussion: EGFR expression is seen in metaplastic breast cancer. Although EGFR expression is related to poor prognosis, it is not a predictive marker. Therefore, predictive molecular markers are

  2. Focal Adhesion Kinase Inhibitors in Combination with Erlotinib Demonstrate Enhanced Anti-Tumor Activity in Non-Small Cell Lung Cancer.

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    Grant A Howe

    Full Text Available Blockade of epidermal growth factor receptor (EGFR activity has been a primary therapeutic target for non-small cell lung cancers (NSCLC. As patients with wild-type EGFR have demonstrated only modest benefit from EGFR tyrosine kinase inhibitors (TKIs, there is a need for additional therapeutic approaches in patients with wild-type EGFR. As a key component of downstream integrin signalling and known receptor cross-talk with EGFR, we hypothesized that targeting focal adhesion kinase (FAK activity, which has also been shown to correlate with aggressive stage in NSCLC, would lead to enhanced activity of EGFR TKIs. As such, EGFR TKI-resistant NSCLC cells (A549, H1299, H1975 were treated with the EGFR TKI erlotinib and FAK inhibitors (PF-573,228 or PF-562,271 both as single agents and in combination. We determined cell viability, apoptosis and 3-dimensional growth in vitro and assessed tumor growth in vivo. Treatment of EGFR TKI-resistant NSCLC cells with FAK inhibitor alone effectively inhibited cell viability in all cell lines tested; however, its use in combination with the EGFR TKI erlotinib was more effective at reducing cell viability than either treatment alone when tested in both 2- and 3-dimensional assays in vitro, with enhanced benefit seen in A549 cells. This increased efficacy may be due in part to the observed inhibition of Akt phosphorylation when the drugs were used in combination, where again A549 cells demonstrated the most inhibition following treatment with the drug combination. Combining erlotinib with FAK inhibitor was also potent in vivo as evidenced by reduced tumor growth in the A549 mouse xenograft model. We further ascertained that the enhanced sensitivity was irrespective of the LKB1 mutational status. In summary, we demonstrate the effectiveness of combining erlotinib and FAK inhibitors for use in known EGFR wild-type, EGFR TKI resistant cells, with the potential that a subset of cell types, which includes A549, could be

  3. SOX2 plays a critical role in EGFR-mediated self-renewal of human prostate cancer stem-like cells.

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    Rybak, Adrian P; Tang, Damu

    2013-12-01

    SOX2 is an essential transcription factor for stem cells and plays a role in tumorigenesis, however its role in prostate cancer stem cells (PCSCs) remains unclear. We report here a significant upregulation of SOX2 at both mRNA and protein levels in DU145 PCSCs propagated as suspension spheres in vitro. The expression of SOX2 in DU145 PCSCs is positively regulated by epidermal growth factor receptor (EGFR) signaling. Activation of EGFR signaling, following the addition of epidermal growth factor (EGF) or ectopic expression of a constitutively-active EGFR mutant (EGFRvIII), increased SOX2 expression and the self-renewal of DU145 PCSCs. Conversely, a small molecule EGFR inhibitor (AG1478) blocked EGFR activation, reduced SOX2 expression and inhibited PCSC self-renewal activity, implicating SOX2 in mediating EGFR-dependent self-renewal of PCSCs. In line with this notion, ectopic SOX2 expression enhanced EGF-induced self-renewal of DU145 PCSCs, while SOX2 knockdown reduced PCSC self-renewal with EGF treatment no longer capable of enhancing their propagation. Furthermore, SOX2 knockdown reduced the capacity of DU145 PCSCs to grow under anchorage-independent conditions. Finally, DU145 PCSCs generated xenograft tumors more aggressively with elevated levels of SOX2 expression compared to xenograft tumors derived from non-PCSCs. Collectively, we provide evidence that SOX2 plays a critical role in EGFR-mediated self-renewal of DU145 PCSCs. © 2013.

  4. Assessment of early changes in 3H-fluorothymidine uptake after treatment with gefitinib in human tumor xenograft in comparison with Ki-67 and phospho-EGFR expression

    International Nuclear Information System (INIS)

    Zhao, Songji; Kuge, Yuji; Zhao, Yan; Takeuchi, Satoshi; Hirata, Kenji; Takei, Toshiki; Shiga, Tohru; Dosaka-Akita, Hirotoshi; Tamaki, Nagara

    2013-01-01

    The purpose of this study was to evaluate whether early changes in 3′-deoxy-3′- 3 H-fluorothymidine ( 3 H-FLT) uptake can reflect the antiproliferative effect of gefitinib in a human tumor xenograft, in comparison with the histopathological markers, Ki-67 and phosphorylated EGFR (phospho-EGFR). An EGFR-dependent human tumor xenograft model (A431) was established in female BALB/c athymic mice, which were divided into three groups: one control group and two treatment groups. Mice in the treatment groups were orally administered a partial regression dose (100 mg/kg/day) or the maximum tolerated dose of gefitinib (200 mg/kg/day), once daily for 2 days. Mice in the control group were administered the vehicle (0.1% Tween 80). Tumor size was measured before and 3 days after the start of treatment. Biodistribution of 3 H-FLT and 18 F-FDG (%ID/g/kg) was examined 3 days after the start of the treatment. Tumor cell proliferative activity with Ki-67 was determined. Immunohistochemical staining of EGFR and measurement of phospho-EGFR were also performed. High expression levels of EGFR and Ki-67 were observed in the A431 tumor. After the treatment with 100 and 200 mg/kg gefitinib, the uptake levels of 3 H-FLT in the tumor were significantly reduced to 67% and 61% of the control value, respectively (0.39 ± 0.09, 0.36 ± 0.06, 0.59 ± 0.11%ID/g/kg for 100 mg/kg, 200 mg/kg, and control groups, respectively; p < 0.01 vs. control), but those of 18 F-FDG were not. After the treatment with 100 and 200 mg/kg gefitinib, the expression levels of Ki-67 in the tumor were markedly decreased (4.6 ± 2.4%, 6.2 ± 1.8%, and 10.4 ± 5.7% for 100 mg/kg, 200 mg/kg, and control groups, respectively, p < 0.01 vs. control). The expression levels of the phospho-EGFR protein also significantly decreased (29% and 21% of the control value for 100, and 200 mg/kg, respectively p < 0.01 vs. control). There was no statistically significant difference in tumor size between pre- and post-treatments in

  5. EGFR gene amplification is relatively common and associates with outcome in intestinal adenocarcinoma of the stomach, gastro-oesophageal junction and distal oesophagus

    International Nuclear Information System (INIS)

    Birkman, Eva-Maria; Ålgars, Annika; Lintunen, Minnamaija; Ristamäki, Raija; Sundström, Jari; Carpén, Olli

    2016-01-01

    and associates with decreased survival. It is rarely concurrent with HER2 gene amplification, suggesting that anti-EGFR therapies might be applicable to some patients not eligible for anti-HER2 treatment. Analogous to HER2 testing, determination of EGFR gene amplification status in concert with immunohistochemistry could improve the specificity of patient selection when investigating the possible benefits of anti-EGFR therapies in the treatment of gastric adenocarcinomas

  6. Acquired EGFR L718V mutation mediates resistance to osimertinib in non-small cell lung cancer but retains sensitivity to afatinib.

    Science.gov (United States)

    Liu, Yutao; Li, Yan; Ou, Qiuxiang; Wu, Xue; Wang, Xiaonan; Shao, Yang W; Ying, Jianming

    2018-04-01

    Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are promising targeted therapies for EGFR-mutated non-small-cell lung cancer (NSCLC) patients. However, acquired resistance inevitably develops. Comprehensive and dynamic companion genomic diagnosis can gain insights into underlying resistance mechanisms, thereby help oncologists and patients to make informed decision on the potential benefit of the treatment. A 67-year-old male who was initially diagnosed of EGFR L858R-mediated NSCLC received multiple lines of chemotherapy and EGFR TKI therapies after surgery. The EGFR mutational status of individual metastatic lesion was determined by genetic testing of the tumor tissue biopsies using next generation sequencing (NGS) throughout the patient's clinical course. An acquired potentially drug-resistant EGFR mutation was functionally validated in vitro and its sensitivity to different EGFR TKIs was assessed simultaneously. We have identified distinct resistance mechanisms to EGFR blockade in different metastatic lung lesions. Acquired EGFR T790M was first detected that leads to the resistance to the gefitinib treatment. Consequently, osimertinib was administrated and the response lasted until disease progressed. We identified a newly acquired EGFR L718V mutation in one lesion in conjunction with L858R, but not T790M, which showed stable disease on the following erlotinib treatment, while EGFR C797S together with L858R/T790M was detected in the other lesion that continuously progressed. In vitro functional studies demonstrated that EGFR-L858R/L718V confers resistance to osimertinib, but retains sensitivity to the second generation TKI afatinib. We reported that distinct resistance mechanisms could arise in different metastases within the same patient in response to EGFR blockade. We also demonstrated in vitro that EGFR L718V mutation mediates resistance to osimertinib, but retains sensitivity to afatinib. We evidenced that dynamic companion genomic

  7. 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

  8. The prognostic values of EGFR expression and KRAS mutation in patients with synchronous or metachronous metastatic colorectal cancer

    International Nuclear Information System (INIS)

    Huang, Ching-Wen; Wang, Jaw-Yuan; Tsai, Hsiang-Lin; Chen, Yi-Ting; Huang, Chun-Ming; Ma, Cheng-Jen; Lu, Chien-Yu; Kuo, Chao-Hung; Wu, Deng-Chyang; Chai, Chee-Yin

    2013-01-01

    The epidermal growth factor receptor (EGFR)/RAS/RAF/MEK/MAPK pathway is an important pathway in the carcinogenesis, invasion and metastasis of colorectal cancers (CRCs). We conducted a retrospective study to determine the prognostic values of EGFR expression and KRAS mutation in patients with metastatic CRC (mCRC) based on synchronous or metachronous status. From October 2002 to March 2012, 205 patients with mCRC were retrospectively analyzed; 98 were found to have metachronous mCRC while 107 were found to have synchronous mCRC. The EGFR expressions were determinate by IHC (immunohistochemistry) analysis and categorized 1+ (weak intensity), 2+ (moderate intensity), and 3+ (strong intensity). Genomic DNA was isolated from frozen primary CRC tissues and direct sequencing of KRAS was performed. The clinicopathological features of these mCRC patients were retrospectively investigated according to EGFR expression and KRAS mutation status. Moreover, we analyzed the prognostic values of EGFR expression and KRAS mutation among these patients. Of the 205 patients with mCRC, EGFR expression was analyzed in 167 patients, and positive EGFR expression was noted in 140 of those patients (83.8%). KRAS mutation was investigated in 205 patients and mutations were noted in 88 of those patients (42.9%). In patients with metachronous mCRC, positive EGFR expression was significantly correlated with well-and moderately-differentiated tumors (P = 0.028), poorer disease-free survival (DFS) (P < 0.001), and overall survival (OS) (P < 0.001). Furthermore, positive EGFR expression was a significant independent prognostic factor of DFS (P = 0.006, HR: 4.012, 95% CI: 1.130–8.445) and OS (P = 0.028, HR: 3.090, 95% CI: 1.477–10.900) in metachronous mCRC patients. KRAS mutation status was not significantly related to DFS and OS of patients with metachronous mCRC; likewise, KRAS mutation status was not significantly different in the progression-free survival (PFS) and OS of patients with

  9. 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.

  10. 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.

    2013-01-01

    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. PMID:23888049

  11. Dual Inhibition of EGFR with Afatinib and Cetuximab in Kinase Inhibitor-Resistant EGFR-Mutant Lung Cancer with and without T790M Mutations

    NARCIS (Netherlands)

    Janjigian, Yelena Y.; Smit, Egbert F.; Groen, Harry J. M.; Horn, Leora; Gettinger, Scott; Camidge, D. Ross; Riely, Gregory J.; Wang, Bushi; Fu, Yali; Chand, Vikram K.; Miller, Vincent A.; Pao, William

    EGFR-mutant lung cancers responsive to reversible EGFR inhibitors (gefitinib/erlotinib) develop acquired resistance, mediated by second-site EGFR T790M mutation in >50% of cases. Preclinically, afatinib (irreversible ErbB family blocker) plus cetuximab (anti-EGFR monoclonal antibody) overcomes

  12. The Use of EGFR Tyrosine Kinase Inhibitors in EGFR Wild-Type Non-Small-Cell Lung Cancer.

    Science.gov (United States)

    Stinchcombe, Thomas E

    2016-04-01

    The objective response rate and progression-free survival observed with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) in patients with metastatic epidermal growth factor receptor (EGFR) wild-type non-small cell lung cancer (NSCLC) are modest. The adverse events associated with EGFR TKIs are manageable but they must be considered in the context of the limited efficacy. The development of anti-PD-1 immunotherapy as second-line therapy has reduced the role of EGFR TKIs in EGFR wild-type NSCLC. Recently, there has been increased recognition of the benefit of the earlier integration of palliative care and symptom management, and this is reasonable alternative to treatment with an EGFR TKI for many patients. My practice pattern for patients with EGFR wild-type NSCLC is platinum-based chemotherapy as first-line therapy, immunotherapy as second-line therapy, and single-agent chemotherapy as third-line therapy for patients with preserved performance status who want to pursue further therapy. Only a small proportion of patients are eligible for fourth-line therapy, and I prefer to enroll them in clinical trials rather than use EGFR TKIs. I suspect that the use of EGFR TKIs in clinical use and as a comparator arm for clinical trials will continue to decline over the next several years.

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

    International Nuclear Information System (INIS)

    Liang, Yu; Bollen, Andrew W; Aldape, Ken D; Gupta, Nalin

    2006-01-01

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

  14. Combination treatment with ionising radiation and gefitinib ('Iressa', ZD1839), an epidermal growth factor receptor (EGFR) inhibitor, significantly inhibits bladder cancer cell growth in vitro and in vivo

    International Nuclear Information System (INIS)

    Colquhoun, AJ; Mchugh, LA; Tulchinsky, E.; Kriajevska, M.; Mellon, JK

    2007-01-01

    External beam radiotherapy (EBRT) is the principal bladder-preserving monotherapy for muscle-invasive bladder cancer. Seventy percent of muscle-invasive bladder cancers express epidermal growth factor receptor (EGFR), which is associated with poor prognosis. Ionising radiation (IR) stimulates EGFR causing activation of cytoprotective signalling cascades and thus may be an underlying cause of radioresistance in bladder tumours. We assessed the ability of IR to activate EGFR in bladder cancer cells and the effect of the anti-EGFR therapy, gefitinib on potential radiation-induced activation. Subsequently we assessed the effect of IR on signalling pathways downstream of EGFR. Finally we assessed the activity of gefitinib as a monotherapy, and in combination with IR, using clonogenic assay in vitro, and a murine model in vivo. IR activated EGFR and gefitinib partially inhibited this activation. Radiation-induced activation of EGFR activated the MAPK and Akt pathways. Gefitinib partially inhibited activation of the MAPK pathway but not the Akt pathway. Treatment with combined gefitinib and IR significantly inhibited bladder cancer cell colony formation more than treatment with gefitinib alone (p=0.001-0.03). J82 xenograft tumours treated with combined gefitinib and IR showed significantly greater growth inhibition than tumours treated with IR alone (p=0.04). Combining gefitinib and IR results in significantly greater inhibition of invasive bladder cancer cell colony formation in vitro and significantly greater tumour growth inhibition in vivo. Given the high frequency of EGFR expression by bladder tumours and the low toxicity of gefitinib there is justification to translate this work into a clinical trial. (author)

  15. Growth/differentiation factor 15 promotes EGFR signalling, and regulates proliferation and migration in the hippocampus of neonatal and young adult mice.

    Science.gov (United States)

    Carrillo-García, Carmen; Prochnow, Sebastian; Simeonova, Ina K; Strelau, Jens; Hölzl-Wenig, Gabriele; Mandl, Claudia; Unsicker, Klaus; von Bohlen Und Halbach, Oliver; Ciccolini, Francesca

    2014-02-01

    The activation of epidermal growth factor receptor (EGFR) affects multiple aspects of neural precursor behaviour, including proliferation and migration. Telencephalic precursors acquire EGF responsiveness and upregulate EGFR expression at late stages of development. The events regulating this process and its significance are still unclear. We here show that in the developing and postnatal hippocampus (HP), growth/differentiation factor (GDF) 15 and EGFR are co-expressed in primitive precursors as well as in more differentiated cells. We also provide evidence that GDF15 promotes responsiveness to EGF and EGFR expression in hippocampal precursors through a mechanism that requires active CXC chemokine receptor (CXCR) 4. Besides EGFR expression, GDF15 ablation also leads to decreased proliferation and migration. In particular, lack of GDF15 impairs both processes in the cornu ammonis (CA) 1 and only proliferation in the dentate gyrus (DG). Importantly, migration and proliferation in the mutant HP were altered only perinatally, when EGFR expression was also affected. These data suggest that GDF15 regulates migration and proliferation by promoting EGFR signalling in the perinatal HP and represent a first description of a functional role for GDF15 in the developing telencephalon.

  16. Alteration of major vault protein in human glioblastoma and its relation with EGFR and PTEN status.

    Science.gov (United States)

    Navarro, L; Gil-Benso, R; Megías, J; Muñoz-Hidalgo, L; San-Miguel, T; Callaghan, R C; González-Darder, J M; López-Ginés, C; Cerdá-Nicolás, M J

    2015-06-25

    Glioblastoma (GBM) is the most frequent and malignant primary brain tumor. Conventional therapy of surgical removal, radiation and chemotherapy is largely palliative. Major vault protein (MVP), the main component of the vault organelle has been associated with multidrug resistance by reducing cellular accumulation of chemotherapeutic agents. With regard to cancer, MVP has been shown to be overexpressed in drug resistance development and malignant progression. The aim of the present study was to evaluate the MVP gene dosage levels in 113 archival samples from GBM and its correlation with patients' survival and epidermal growth factor receptor (EGFR) and phosphatase and tensin homolog (PTEN) gene dosages. Fluorescent in situ hybridization revealed polysomy of chromosome 7 in 76.1% of the GBMs and EGFR amplification in a 64.6% of the tumors. Genetic status of EGFR, PTEN and MVP copies was determined by multiplex ligation-dependent probe amplification (MLPA) technique. 31% of the tumors showed the EGFR is variant III mutation (EGFRvIII) mutation and 74.3% of them presented amplification of MVP gene. Amplification of EGFR and MVP was found in a 63.7% and 56.6% of the GBM, respectively. An inverse correlation between MVP and PTEN dosage values was observed. Besides, an inverse relationship between the survival of the patients treated with chemotherapy and the levels of MVP copies was determined. In conclusion, our study reveals an important role of MVP, together with EGFRvIII and PTEN, in the progression of GBM and proposes it as a novel and interesting target for new treatment approaches. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  17. iRhom2 promotes lupus nephritis through TNF-α and EGFR signaling.

    Science.gov (United States)

    Qing, Xiaoping; Chinenov, Yurii; Redecha, Patricia; Madaio, Michael; Roelofs, Joris Jth; Farber, Gregory; Issuree, Priya D; Donlin, Laura; Mcllwain, David R; Mak, Tak W; Blobel, Carl P; Salmon, Jane E

    2018-04-02

    Lupus nephritis (LN) often results in progressive renal dysfunction. The inactive rhomboid 2 (iRhom2) is a newly identified key regulator of A disintegrin and metalloprotease 17 (ADAM17), whose substrates, such as TNF-α and heparin-binding EGF (HB-EGF), have been implicated in the pathogenesis of chronic kidney diseases. Here, we demonstrate that deficiency of iRhom2 protects the lupus-prone Fcgr2b-/- mice from developing severe kidney damage without altering anti-double-stranded DNA (anti-dsDNA) Ab production by simultaneously blocking HB-EGF/EGFR and TNF-α signaling in the kidney tissues. Unbiased transcriptome profiling of kidneys and kidney macrophages revealed that TNF-α and HB-EGF/EGFR signaling pathways are highly upregulated in Fcgr2b-/- mice, alterations that were diminished in the absence of iRhom2. Pharmacological blockade of either TNF-α or EGFR signaling protected Fcgr2b-/- mice from severe renal damage. Finally, kidneys from LN patients showed increased iRhom2 and HB-EGF expression, with interstitial HB-EGF expression significantly associated with chronicity indices. Our data suggest that activation of iRhom2/ADAM17-dependent TNF-α and EGFR signaling plays a crucial role in mediating irreversible kidney damage in LN, thereby uncovering a target for selective and simultaneous dual inhibition of 2 major pathological pathways in the effector arm of the disease.

  18. 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.

  19. A camelid nanobody against EGFR was easily obtained through refolding of inclusion body expressed in Escherichia coli.

    Science.gov (United States)

    Xu, Li; Song, Xiaoyu; Jia, Lingyun

    2017-11-01

    Using anti-EGFR (epidermal growth factor receptor) nanobody is a good choice for diagnoses and therapeutics for high EGFR expression diseases. In the present study, the percentage composition of anti-EGFR nanobody attained 25% of the total cell protein expressed in Escherichia coli BL21 (DE3). However, almost all nanobodies were expressed as inclusion bodies. To acquire active nanobodies, a series of dilution refolding procedures were optimized after inclusion bodies were dissolved into 6 M urea and purified with immobilized metal affinity chromatography. The results showed the refolding rate of the anti-EGFR nanobodies attained to 73%, and about 100 mg nanobodies were refolded from 1 L cells under the conditions that the initial nanobody concentration was 0.3 mg/mL, the dilution speed was 2.5 mL/Min, the dilution buffer was Tris-HCl at pH 8.0, the additives were 0.2 M Arg, 5 mM reduced glutathione (GSH), and 1 mM oxidized glutathione (GSSG). Then the activity of the refolded nanobodies was confirmed. The results showed that the refolded anti-EGFR nanobodies, in a dose-dependent manner, bounded to the tumor cell surface of A431 and MCF-7 and significantly inhibited the proliferation of A431 caused by the epidermal growth factor. Our study provides a facile method to rapidly, efficiently, and massively prepare anti-EGFR antibodies and promotes anti-EGFR-based recognition in cancer diagnoses and therapeutics. © 2016 International Union of Biochemistry and Molecular Biology, Inc.

  20. Targeted sequencing identifies genetic alterations that confer primary resistance to EGFR tyrosine kinase inhibitor (Korean Lung Cancer Consortium).

    Science.gov (United States)

    Lim, Sun Min; Kim, Hye Ryun; Cho, Eun Kyung; Min, Young Joo; Ahn, Jin Seok; Ahn, Myung-Ju; Park, Keunchil; Cho, Byoung Chul; Lee, Ji-Hyun; Jeong, Hye Cheol; Kim, Eun Kyung; Kim, Joo-Hang

    2016-06-14

    Non-small-cell lung cancer (NSCLC) patients with activating epidermal growth factor receptor (EGFR) mutations may exhibit primary resistance to EGFR tyrosine kinase inhibitor (TKI). We aimed to examine genomic alterations associated with de novo resistance to gefitinib in a prospective study of NSCLC patients. One-hundred and fifty two patients with activating EGFR mutations were included in this study and 136 patients' tumor sample were available for targeted sequencing of genomic alterations in 22 genes using the Colon and Lung Cancer panel (Ampliseq, Life Technologies). All 132 patients with EGFR mutation were treated with gefitinib for their treatment of advanced NSCLC. Twenty patients showed primary resistance to EGFR TKI, and were classified as non-responders. A total of 543 somatic single-nucleotide variants (498 missense, 13 nonsense) and 32 frameshift insertions/deletions, with a median of 3 mutations per sample. TP53 was most commonly mutated (47%) and mutations in SMAD4 was also common (19%), as well as DDR2 (16%), PIK3CA (15%), STK11 (14%), and BRAF (7%). Genomic mutations in the PI3K/Akt/mTOR pathway were commonly found in non-responders (45%) compared to responders (27%), and they had significantly shorter progression-free survival and overall survival compared to patients without mutations (2.1 vs. 12.8 months, P=0.04, 15.7 vs. not reached, PAkt/mTOR pathway were commonly identified in non-responders and may confer resistance to EGFR TKI. Screening lung adenocarcinoma patients with clinical cancer gene test may aid in selecting out those who show primary resistance to EGFR TKI (NCT01697163).

  1. EGFR-dependent signalling reduced and p38 dependent apoptosis required by Gallic acid in Malignant Mesothelioma cells.

    Science.gov (United States)

    Demiroglu-Zergeroglu, Asuman; Candemir, Gulsife; Turhanlar, Ebru; Sagir, Fatma; Ayvali, Nurettin

    2016-12-01

    The unrestrained EGFR signalling contributes to malignant phenotype in a number of cancers including Malignant Mesotheliomas. Present study was designed to evaluate EGFR-dependent anti-proliferative and apoptotic effects of Gallic acid in transformed Mesothelial (MeT-5A) and Malignant Mesothelioma (SPC212) cells. Gallic acid reduced the viability of Malignant Mesothelioma cells in a concentration and time-dependent manner. However, viability of mesothelial cells reduced only at high concentration and longer time periods. Gallic acid restrained the activation of EGFR, ERK1/2 and AKT proteins and down regulated expression of Cyclin D and Bcl-2 genes, but upregulated the expression of p21 gene in EGF-induced SPC212 cells. GA-induced transitory G1 arrest and triggered mitochondrial and death receptor mediated apoptosis, which requires p38MAPK activation. The data provided here indicate that GA is able to inhibit EGFR dependent proliferation and survival signals and induces p38 pathway dependent apoptosis in Malignant Mesothelioma cells. On the basis of these experimental findings it is worthwhile to investigate further the biological activity of Gallic acid on other Mesothelioma cell lines harbouring aberrant EGFR signals. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  2. PAI-1 and EGFR expression in adult glioma tumors: toward a molecular prognostic classification

    International Nuclear Information System (INIS)

    Muracciole, Xavier; Romain, Sylvie; Dufour, Henri; Palmari, Jacqueline; Chinot, Olivier; Ouafik, L'Houcine; Grisoli, Francois; Figarella-Branger, Dominique; Martin, Pierre-Marie

    2002-01-01

    Purpose: Molecular classification of gliomas is a major challenge in the effort to improve therapeutic decisions. The plasminogen activator system, including plasminogen activator inhibitor type 1 (PAI-1), plays a key role in tumor invasion and neoangiogenesis. Epidermal growth factor receptor (EGFR) is involved in the control of proliferation. The contribution of PAI-1 and EGFR to the survival of gliomas was retrospectively investigated. Methods and Materials: Fifty-nine adult gliomas treated by neurosurgery and conventional irradiation were analyzed, including 9 low-grade (2) and 50 high-grade (3-4) tumors (WHO classification). PAI-1 was measured on cytosols and EGFR on solubilized membranes using ELISA methods. Results: High PAI-1 levels were strongly associated with high histologic grade (p<0.001) and histologic necrosis (p<0.001). PAI-1 also correlated positively with patient age (p=0.05) and negatively with Karnofsky index (p=0.01). By univariate analysis of the high-grade population, higher PAI-1 (p<0.0001) and EGFR values (p=0.02) were associated with shorter overall survival. Only PAI-1 was an independent factor in multivariate analysis. Grade 3 tumors with low PAI-1 (100% 3-year overall survival rate) presented the same clinical outcome as the low-grade tumors. Conclusions: In this prognostic study, PAI-1 and EGFR expression revealed similarities and differences between high-grade gliomas that were not apparent by traditional clinical criteria. These data strongly support that biologic factors should be included in glioma classification and the design of clinical trials to treat more homogeneous populations

  3. Epidermal to Mesenchymal Transition and Failure of EGFR-Targeted Therapy in Glioblastoma

    Directory of Open Access Journals (Sweden)

    Marc-Eric Halatsch

    2012-05-01

    Full Text Available Glioblastoma multiforme (GBM, the most common primary brain tumor in adults, is almost never curable with the current standard treatment consisting of surgical resection, irradiation and temozolomide. The prognosis remains poor despite undisputable advances in the understanding of this tumor’s molecular biology and pathophysiology, which unfortunately has so far failed to translate into a meaningful clinical benefit. Dysregulation and a resulting prominent pathophysiological role of the epidermal growth factor receptor (EGFR have been identified in several different malignant tumor entities, GBM among them. The EGFR is overexpressed in about 40% of GBM cases, and half of these coexpress a mutant, constitutively activated subtype, EGFRvIII. Unfortunately, recent trials studying with therapeutic approaches targeted against the EGFR and EGFRvIII have failed to meet expectations, with only a minority of patients responding despite evidence of good in vitro and rodent model activity. Having potentially high relevance within this context, epithelial to mesenchymal transition (EMT is a phenomenon associated with early stages of carcinogenesis, cancer invasion and recurrence. During EMT, epithelial cells lose many of their epithelial characteristics, prominently E-cadherin expression, and acquire properties that are typical for mesenchymal cells such as the expression of vimentin. Epithelial to mesenchymal transition has been specifically demonstrated in GBM. In this review, we summarize the evidence that EMT may precipitate GBM resistance to EGFR-targeted therapy, and may thus be among the principal factors contributing to the clinical failure of targeted therapy against EGFR and EGFRvIII.

  4. Phosphorus Determination by Derivative Activation Analysis: A Multifaceted Radiochemical Application.

    Science.gov (United States)

    Kleppinger, E. W.; And Others

    1984-01-01

    Although determination of phosphorus is important in biology, physiology, and environmental science, traditional gravimetric and colorimetric methods are cumbersome and lack the requisite sensitivity. Therefore, a derivative activation analysis method is suggested. Background information, procedures, and results are provided. (JN)

  5. Dose Determination of Activated Charcoal in Management of ...

    African Journals Online (AJOL)

    measured by high performance liquid chromatography (HPLC) for dose determination of activated ... paracetamol, benzodiazepines and alcohol [11]. .... Stability. The stability (short term) of standard and amitriptyline sample solutions was ...

  6. Determinants of Fisher's Choice of Fishing Activity along the Volta ...

    African Journals Online (AJOL)

    Determinants of Fisher's Choice of Fishing Activity along the Volta Lake in Yeji ... The analysis was done using the Ordered Probit Model and descriptive statistics. ... economic growth, reduce poverty and ensure household food security in Yeji.

  7. Comparison of EGFR and KRAS Status between Primary Non-small Cell Lung Cancer and Corresponding Metastases: A Systematic Review and meta-analysis

    Directory of Open Access Journals (Sweden)

    Chengbo HAN

    2010-09-01

    Full Text Available Background and objective Epidermal growth factor receptor (EGFR and KRAS status were particularly critical for the choice of first-line targeted therapy of non-small cell lung cancer (NSCLC, while the primary tumor and metastases might be different in the EGFR and KRAS gene status. The aim of this pooled analysis is to compare EGFR and KRAS status in matching primary NSCLC and metastases and further to guide clinical practice. Methods Systematic computerized searches of the Pubmed and Medline databases (up to May 10, 2010 meeting specified search criteria were performed, followed by a further screening according to inclusive and exclusive criteria. Results Fourteen articles were selected into the final meta-analysis with paired primary and metastatic cases of 598. Expression level of EGFR protein and mutation frequency of KRAS gene in primary tumors were higher than that in metastases, relative risk (RR=1.13 (95%CI: 0.98-1.31, P=0.09 and RR=1.39 (95%CI: 0.95-2.03, P=0.09, respectively. EGFR gene copy number in metastases was higher than that in primary tumor, RR=0.74 (95%CI: 0.53-1.02, P=0.06. There was no statistically significant difference of EGFR mutation frequency in primary tumors and metastases (P=0.31. The discordant rate in primary and metastases was 17.09% for EGFR mutation, 27.07% for EGFR amplification, 27.84% for EGFR protein expression and 25.91% for KRAS mutation. Conclusion The systematic analysis showed that the EGFR mutation status in primary lung cancer and corresponding metastases was more stable than KRAS gene. KRAS mutation in primary lung cancerous foci seems to better reflect systemically cancerous genetic characteristics of KRAS gene. Determination of KRAS gene status based merely on metastatic foci might lead to more resistant selections of EGFR tyrosine kinase inhibitor (TKI therapy. Combined detection of EGFR and KRAS mutation from primary NSCLC foci might serve as a better predictive biomarker for anti-EGFR targeted

  8. Effects of the EGFR Inhibitor Erlotinib on Magnesium Handling

    NARCIS (Netherlands)

    Dimke, Henrik; van der Wijst, Jenny; Alexander, Todd R.; Meijer, Inez M. J.; Mulder, Gemma M.; van Goor, Harry; Tejpar, Sabine; Hoenderop, Joost G.; Bindels, Rene J.

    A mutation in pro-EGF causes isolated hypomagnesemia, and monoclonal antibodies targeting the extracellular domain of the EGF receptor (EGFR) affect epithelial Mg2+ transport. The effect of the EGFR tyrosine kinase inhibitor erlotinib on Mg2+ homeostasis, however, remains unknown. Here, we injected

  9. Detecting and treating breast cancer resistance to EGFR inhibitors

    Science.gov (United States)

    Moonlee, Sun-Young; Bissell, Mina J.; Furuta, Saori; Meier, Roland; Kenny, Paraic A.

    2016-04-05

    The application describes therapeutic compositions and methods for treating cancer. For example, therapeutic compositions and methods related to inhibition of FAM83A (family with sequence similarity 83) are provided. The application also describes methods for diagnosing cancer resistance to EGFR inhibitors. For example, a method of diagnosing cancer resistance to EGFR inhibitors by detecting increased FAM83A levels is described.

  10. Decreased EGFR mRNA expression in response to antipsoriatic ...

    African Journals Online (AJOL)

    Dithranol is enormously effective in the treatment of psoriasis; however its molecular mode of action should be further elucidated. Since epidermal growth factor receptor (EGFR) is involved in the pathogenesis of psoriasis, the objective of this study was to investigate the transcriptional effect of dithranol on EGFR gene ...

  11. EGFR and KRAS mutation coexistence in lung adenocarcinomas

    Directory of Open Access Journals (Sweden)

    Vitor Manuel Leitão de Sousa

    2015-04-01

    Full Text Available Lung cancer is one of the most common causes of cancer deaths. The development of EGFR targeted therapies, including monoclonal antibodies and tyrosine kinase inhibitors have generated an interest in the molecular characterization of these tumours. KRAS mutations are associated with resistance to EGFR TKIs. EGFR and KRAS mutations have been considered as mutually exclusive. This paper presents three bronchial-pulmonary carcinomas, two adenocarcinomas and one pleomorphic sarcomatoid carcinoma, harboring EGFR and KRAS mutations. Case 1 corresponded to an adenocarcinoma with EGFR exon 21 mutation (L858R and KRAS codon 12 point mutation (G12V; case 2, a  mucinous adenocarcinoma expressed coexistence of EGFR exon 21 mutation (L858R and KRAS codon 12 point mutation (G12V; and case 3 a sarcomatoid carcinoma with EGFR exon 19 deletion – del 9bp and KRAS codon 12 point mutation (G12C - cysteine. Based on our experience and on the literature, we conclude that EGFR and KRAS mutations can indeed coexist in the same bronchial-pulmonary carcinoma, either in the same histological type or in different patterns. The biological implications of this coexistence are still poorly understood mainly because these cases are not frequent or currently searched. It is therefore necessary to study larger series of cases with the two mutations to better understand the biological, clinical and therapeutic implications.

  12. Determination of rhenium in molybdenite by neutron-activation analysis.

    Science.gov (United States)

    Terada, K; Yoshimura, Y; Osaki, S; Kiba, T

    1967-01-01

    A neutron-activation method is described for the determination of rhenium in molybdenite. Radiochemical separation by a carrier technique was carried out very rapidly by means of successive liquid-liquid extraction processes. The recovery of rhenium, which was determined by a spectrophotometric method, was about 93%. About 10 samples could be analysed within 6 hr in parallel runs.

  13. Determination of activities of human carbonic anhydrase II inhibitors ...

    African Journals Online (AJOL)

    Purpose: To evaluate the activities of new curcumin analogs as carbonic anhydrase II (CA-II) inhibitor. Methods: Carbonic anhydrase II (CA-II) inhibition was determined by each ligand capability to inhibit the esterase activity of CA-II using 4-NPA as a substrate in 96-well plates. Dimethyl sulfoxide was used to dissolve each ...

  14. Determinants of Foreign Technological Activity in German Regions

    DEFF Research Database (Denmark)

    Dettmann, Eva; Lacasa, Iciar Dominguez; Günther, Jutta

    This paper analyses the determinants of spatial distribution of foreign technological activity across 96 German regions (1996-2009). We identify foreign inventive activity by applying the ‘cross-border-ownership concept’ to transnational patent applications. The descriptive analysis shows...

  15. 48 CFR 218.270 - Head of contracting activity determinations.

    Science.gov (United States)

    2010-10-01

    ... REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES EMERGENCY ACQUISITIONS Emergency Acquisition Flexibilities 218.270 Head of contracting activity determinations. For contract... contracting activity,” as defined in FAR 2.101, in the following locations: (a) FAR 2.101: (1) Definition of...

  16. Determination of average activating thermal neutron flux in bulk samples

    International Nuclear Information System (INIS)

    Doczi, R.; Csikai, J.; Doczi, R.; Csikai, J.; Hassan, F. M.; Ali, M.A.

    2004-01-01

    A previous method used for the determination of the average neutron flux within bulky samples has been applied for the measurements of hydrogen contents of different samples. An analytical function is given for the description of the correlation between the activity of Dy foils and the hydrogen concentrations. Results obtained by the activation and the thermal neutron reflection methods are compared

  17. Determination of amylase activity of crude extract from partially ...

    African Journals Online (AJOL)

    Amylase activity of crude extract from partially germinated mango seeds ( Mangifera oraphila) was determined using Caraway-Somogyi iodine/potassium iodide (IKI) method. The effects of varied pH and temperature were also investigated. The amylase was extracted with 0.1 M acetate buffer (pH 4.2). Amylase activity of the ...

  18. Determination of activated plasma fibronectin using radioactive labelled collagen I

    DEFF Research Database (Denmark)

    Fenger, M

    1984-01-01

    The plasma concentration of biological active fibronectin was assayed by a protein binding assay using 125I-collagen I as ligand and heparin as activator. The standard curve is linear for a fibronectin range of 1.1-11 pmol (0.5-5.0 micrograms) and the coefficient of variation was less than 10......%. The active or activable fibronectin was compared to the immunoreactive fibronectin in plasma from patients with various bacterial diseases. Similar concentrations were detected by the two assays suggesting that all the circulating fibronectin was functionally active. The assay was also applied to determine...

  19. Effects of icotinib, a novel epidermal growth factor receptor tyrosine kinase inhibitor, in EGFR-mutated non-small cell lung cancer.

    Science.gov (United States)

    Yang, Guangdie; Yao, Yinan; Zhou, Jianya; Zhao, Qiong

    2012-06-01

    Epidermal growth factor receptor (EGFR) is one of the most promising targets for non-small cell lung cancer (NSCLC). Our study demonstrated the antitumor effects of icotinib hydrochloride, a highly selective epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI), in two EGFR-mutated lung cancer cell lines compared to A549, a cell line without EGFR mutations. We incubated PC-9 and HCC827 human lung cancer cell lines both with (E746-A750) mutations with various concentrations of icotinib and gefitinib for 48 h. Cell proliferation and migration were determined using a real-time cell invasion and migration assay and cytotoxicity assay. Apoptosis was assessed by measuring Annexin V staining using flow cytometry. The antitumor effects of icotinib compared to gefitinib were similar and were most effective in reducing the proliferation of EGFR-mutated cells compared to non-mutated controls. Our results suggest the possibility of icotinib as a new therapeutic agent of EGFR-mutated cancer cells, which has the potential to be used in the first-line treatment of EGFR-mutated NSCLC.

  20. Clinical and CT characteristics of surgically resected lung adenocarcinomas harboring ALK rearrangements or EGFR mutations

    International Nuclear Information System (INIS)

    Wang, Hua; Schabath, Matthew B.; Liu, Ying; Han, Ying; Li, Qi; Gillies, Robert J.; Ye, Zhaoxiang

    2016-01-01

    Purpose: To determine if clinical and CT characteristics of surgically resected lung adenocarcinomas can distinguish those harboring ALK rearrangements from EGFR mutations. Materials and methods: Patients who had surgical resection and histologically confirmed lung adenocarcinoma were enrolled, including 41 patients with ALK rearrangements and 66 patients with EGFR mutations. Eighteen categorical and six quantitative CT characteristics were used to evaluate the tumors. Differences in clinical and CT characteristics between the two groups were investigated. Results: Age (P = 0.003), histological subtypes (P < 0.001), pathological stage (P = 0.007), and five CT characteristics, including size (P < 0.001), GGO (P = 0.001), bubble-like lucency (P = 0.048), lymphadenopathy (P = 0.001), and tumor shadow disappearance rate (P = 0.005) were significantly different between patients harboring ALK rearrangements compared to patients with EGFR mutations. When we compared histologic components, a solid pattern was more common (P = 0.009) in tumors with ALK rearrangements, and lepidic and acinar patterns were more common (P < 0.001 and P = 0.040, respectively) in those with EGFR mutations. Backward elimination analyses revealed that age (OR = 0.93; 95% CI 0.89–0.98), GGO (OR = 0.14; 95% CI 0.03–0.67), and lymphadenopathy (OR = 4.15; 95% CI 1.49–11.60) were significantly associated with ALK rearrangement status. Conclusion: Our analyses revealed that clinical and CT characteristics of lung adenocarcinomas harboring ALK rearrangements were significantly different, compared with those with EGFR mutations. These differences may be related to the molecular pathology of these diseases.

  1. Clinical and CT characteristics of surgically resected lung adenocarcinomas harboring ALK rearrangements or EGFR mutations

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hua [Department of Radiology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin (China); Schabath, Matthew B. [Department of Cancer Epidemiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States); Liu, Ying [Department of Radiology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin (China); Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States); Han, Ying [Department of Biotherapy, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin (China); Li, Qi [Department of Pathology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin (China); Gillies, Robert J. [Department of Cancer Imaging and Metabolism, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States); Department of Radiology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL (United States); Ye, Zhaoxiang, E-mail: yezhaoxiang@163.com [Department of Radiology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center of Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin (China)

    2016-11-15

    Purpose: To determine if clinical and CT characteristics of surgically resected lung adenocarcinomas can distinguish those harboring ALK rearrangements from EGFR mutations. Materials and methods: Patients who had surgical resection and histologically confirmed lung adenocarcinoma were enrolled, including 41 patients with ALK rearrangements and 66 patients with EGFR mutations. Eighteen categorical and six quantitative CT characteristics were used to evaluate the tumors. Differences in clinical and CT characteristics between the two groups were investigated. Results: Age (P = 0.003), histological subtypes (P < 0.001), pathological stage (P = 0.007), and five CT characteristics, including size (P < 0.001), GGO (P = 0.001), bubble-like lucency (P = 0.048), lymphadenopathy (P = 0.001), and tumor shadow disappearance rate (P = 0.005) were significantly different between patients harboring ALK rearrangements compared to patients with EGFR mutations. When we compared histologic components, a solid pattern was more common (P = 0.009) in tumors with ALK rearrangements, and lepidic and acinar patterns were more common (P < 0.001 and P = 0.040, respectively) in those with EGFR mutations. Backward elimination analyses revealed that age (OR = 0.93; 95% CI 0.89–0.98), GGO (OR = 0.14; 95% CI 0.03–0.67), and lymphadenopathy (OR = 4.15; 95% CI 1.49–11.60) were significantly associated with ALK rearrangement status. Conclusion: Our analyses revealed that clinical and CT characteristics of lung adenocarcinomas harboring ALK rearrangements were significantly different, compared with those with EGFR mutations. These differences may be related to the molecular pathology of these diseases.

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

    International Nuclear Information System (INIS)

    Xu, Ling; Hausmann, Martin; Dietmaier, Wolfgang; Kellermeier, Silvia; Pesch, Theresa; Stieber-Gunckel, Manuela; Lippert, Elisabeth; Klebl, Frank; Rogler, Gerhard

    2010-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Kellermeier Silvia

    2010-06-01

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

  4. Quantitative proteomic analysis reveals effects of epidermal growth factor receptor (EGFR) on invasion-promoting proteins secreted by glioblastoma cells.

    Science.gov (United States)

    Sangar, Vineet; Funk, Cory C; Kusebauch, Ulrike; Campbell, David S; Moritz, Robert L; Price, Nathan D

    2014-10-01

    Glioblastoma multiforme is a highly invasive and aggressive brain tumor with an invariably poor prognosis. The overexpression of epidermal growth factor receptor (EGFR) is a primary influencer of invasion and proliferation in tumor cells and the constitutively active EGFRvIII mutant, found in 30-65% of Glioblastoma multiforme, confers more aggressive invasion. To better understand how EGFR contributes to tumor aggressiveness, we investigated the effect of EGFR on the secreted levels of 65 rationally selected proteins involved in invasion. We employed selected reaction monitoring targeted mass spectrometry using stable isotope labeled internal peptide standards to quantity proteins in the secretome from five GBM (U87) isogenic cell lines in which EGFR, EGFRvIII, and/or PTEN were expressed. Our results show that cell lines with EGFR overexpression and constitutive EGFRvIII expression differ remarkably in the expression profiles for both secreted and intracellular signaling proteins, and alterations in EGFR signaling result in reproducible changes in concentrations of secreted proteins. Furthermore, the EGFRvIII-expressing mutant cell line secretes the majority of the selected invasion-promoting proteins at higher levels than other cell lines tested. Additionally, the intracellular and extracellular protein measurements indicate elevated oxidative stress in the EGFRvIII-expressing cell line. In conclusion, the results of our study demonstrate that EGFR signaling has a significant effect on the levels of secreted invasion-promoting proteins, likely contributing to the aggressiveness of Glioblastoma multiforme. Further characterization of these proteins may provide candidates for new therapeutic strategies and targets as well as biomarkers for this aggressive disease. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. Systems biology modeling reveals a possible mechanism of the tumor cell death upon oncogene inactivation in EGFR addicted cancers.

    Directory of Open Access Journals (Sweden)

    Jian-Ping Zhou

    Full Text Available Despite many evidences supporting the concept of "oncogene addiction" and many hypotheses rationalizing it, there is still a lack of detailed understanding to the precise molecular mechanism underlying oncogene addiction. In this account, we developed a mathematic model of epidermal growth factor receptor (EGFR associated signaling network, which involves EGFR-driving proliferation/pro-survival signaling pathways Ras/extracellular-signal-regulated kinase (ERK and phosphoinositol-3 kinase (PI3K/AKT, and pro-apoptotic signaling pathway apoptosis signal-regulating kinase 1 (ASK1/p38. In the setting of sustained EGFR activation, the simulation results show a persistent high level of proliferation/pro-survival effectors phospho-ERK and phospho-AKT, and a basal level of pro-apoptotic effector phospho-p38. The potential of p38 activation (apoptotic potential due to the elevated level of reactive oxygen species (ROS is largely suppressed by the negative crosstalk between PI3K/AKT and ASK1/p38 pathways. Upon acute EGFR inactivation, the survival signals decay rapidly, followed by a fast increase of the apoptotic signal due to the release of apoptotic potential. Overall, our systems biology modeling together with experimental validations reveals that inhibition of survival signals and concomitant release of apoptotic potential jointly contribute to the tumor cell death following the inhibition of addicted oncogene in EGFR addicted cancers.

  6. Determination of superoxide dismutase mimetic activity in common culinary herbs.

    Science.gov (United States)

    Chohan, Magali; Naughton, Declan P; Opara, Elizabeth I

    2014-01-01

    Under conditions of oxidative stress, the removal of superoxide, a free radical associated with chronic inflammation, is catalysed by superoxide dismutase (SOD). Thus in addition to acting as an antioxidant, SOD may also be utilized as an anti-inflammatory agent. Some plant derived foods have been shown to have SOD mimetic (SODm) activity however it is not known if this activity is possessed by culinary herbs which have previously been shown to possess both antioxidant and anti-inflammatory properties. The aim of the study was to ascertain if the culinary herbs rosemary, sage and thyme possess SODm activity, and to investigate the influence of cooking and digestion on this activity. Transition metal ion content was also determined to establish if it could likely contribute to any SODm activity detected. All extracts of uncooked (U), cooked (C) and cooked and digested (C&D) herbs were shown to possess SODm activity, which was significantly correlated with previously determined antioxidant and anti-inflammatory activities of these herbs. SODm activity was significantly increased following (C) and (C&D) for rosemary and sage only. The impact of (C) and (C&D) on the SODm for thyme may have been influenced by its transition metal ion content. SODm activity may contribute to the herbs' antioxidant and anti-inflammatory activities however the source and significance of this activity need to be established.

  7. Manganese contents of soils as determined by activation analysis

    International Nuclear Information System (INIS)

    El-Kholi, A.F.; Hamdy, A.A.; Al Metwally, A.I.; El-Damaty, A.H.

    1976-01-01

    The object of this investigation is to determine total manganese by means of neutron activation analysis and evaluate this technique in comparison with the corresponding data obtained by conventional chemical analysis. Data obtained revealed that the values of total manganese in calcareous soils obtained by both chemical analysis and that by neutron activation analysis were similar. Therefore, activation analysis could be recommended as a quick laboratory, less tedious, and time consuming method for the determination of Mn content in both soils and plants than the conventional chemical techniques due to its great specificity, sensitivity and simplicity. Statistical analysis showed that there is a significant correlation at 5% probability level between manganese content in Soybean plant and total manganese determined by activation and chemical analysis giving the evidence that in the case of those highly calcareous soils of low total manganese content this fraction has to be considered as far as available soil manganese is concerned

  8. Single molecule force spectroscopy for in-situ probing oridonin inhibited ROS-mediated EGF-EGFR interactions in living KYSE-150 cells.

    Science.gov (United States)

    Pi, Jiang; Jin, Hua; Jiang, Jinhuan; Yang, Fen; Cai, Huaihong; Yang, Peihui; Cai, Jiye; Chen, Zheng W

    2017-05-01

    As the active anticancer component of Rabdosia Rubescens, oridonin has been proved to show strong anticancer activity in cancer cells, which is also found to be closely related to its specific inhibition effects on the EGFR tyrosine kinase activity. In this study, atomic force microscopy based single molecule force spectroscopy (AFM-SMFS) was used for real-time and in-situ detection of EGF-EGFR interactions in living esophageal cancer KYSE-150 cells to evaluate the anticancer activity of oridonin for the first time. Oridonin was found to induce apoptosis and also reduce EGFR expression in KYSE-150 cells. AFM-SMFS results demonstrated that oridonin could inhibit the binding between EGF and EGFR in KYSE-150 cells by decreasing the unbinding force and binding probability for EGF-EGFR complexes, which was further proved to be closely associated with the intracellular ROS level. More precise mechanism studies based on AFM-SMFS demonstrated that oridonin treatment could decrease the energy barrier width, increase the dissociation off rate constant and decrease the activation energy of EGF-EGFR complexes in ROS dependent way, suggesting oridonin as a strong anticancer agent targeting EGF-EGFR interactions in cancer cells through ROS dependent mechanism. Our results not only suggested oridonin as a strong anticancer agent targeting EGF-EGFR interactions in ROS dependent mechanism, but also highlighted AFM-SMFS as a powerful technique for pharmacodynamic studies by detecting ligand-receptor interactions, which was also expected to be developed into a promising tool for the screening and mechanism studies of drugs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. The association between creatinine versus cystatin C-based eGFR and cardiovascular risk in children with chronic kidney disease using a modified PDAY risk score.

    Science.gov (United States)

    Sharma, Sheena; Denburg, Michelle R; Furth, Susan L

    2017-08-01

    Children with chronic kidney disease (CKD) have a high prevalence of cardiovascular disease (CVD) risk factors which may contribute to the development of cardiovascular events in adulthood. Among adults with CKD, cystatin C-based estimates of glomerular filtration rate (eGFR) demonstrate a stronger predictive value for cardiovascular events than creatinine-based eGFR. The PDAY (Pathobiological Determinants of Atherosclerosis in Youth) risk score is a validated tool used to estimate the probability of advanced coronary atherosclerotic lesions in young adults. To assess the association between cystatin C-based versus creatinine-based eGFR (eGFR cystatin C and eGFR creatinine, respectively) and cardiovascular risk using a modified PDAY risk score as a proxy for CVD in children and young adults. We performed a cross-sectional study of 71 participants with CKD [median age 15.5 years; inter-quartile range (IQR) 13, 17], and 33 healthy controls (median age 15.1 years; IQR 13, 17). eGFR was calculated using age-appropriate creatinine- and cystatin C-based formulas. Median eGFR creatinine and eGFR cystatin C for CKD participants were 50 (IQR 30, 75) and 53 (32, 74) mL/min/1.73 m 2 , respectively. For the healthy controls, median eGFR creatinine and eGFR cystatin were 112 (IQR 85, 128) and 106 mL/min/1.73m 2 (95, 123) mL/min/1.73 m 2 , respectively. A modified PDAY risk score was calculated based on sex, age, serum lipoprotein concentrations, obesity, smoking status, hypertension, and hyperglycemia. Modified PDAY scores ranged from -2 to 20. The Spearman's correlations of eGFR creatinine and eGFR cystatin C with coronary artery PDAY scores were -0.23 (p = 0.02) and -0.28 (p = 0.004), respectively. Ordinal logistic regression also showed a similar association of higher eGFR creatinine and higher eGFR cystatin C with lower PDAY scores. When stratified by age creatinine and eGFR cystatin C with PDAY score were modest and similar in children [-0.29 (p = 0.008) vs. -0.32 (p = 0

  10. Direct determination of phosphatase activity from physiological substrates in cells.

    Directory of Open Access Journals (Sweden)

    Zhongyuan Ren

    Full Text Available A direct and continuous approach to determine simultaneously protein and phosphate concentrations in cells and kinetics of phosphate release from physiological substrates by cells without any labeling has been developed. Among the enzymes having a phosphatase activity, tissue non-specific alkaline phosphatase (TNAP performs indispensable, multiple functions in humans. It is expressed in numerous tissues with high levels detected in bones, liver and neurons. It is absolutely required for bone mineralization and also necessary for neurotransmitter synthesis. We provided the proof of concept that infrared spectroscopy is a reliable assay to determine a phosphatase activity in the osteoblasts. For the first time, an overall specific phosphatase activity in cells was determined in a single step by measuring simultaneously protein and substrate concentrations. We found specific activities in osteoblast like cells amounting to 116 ± 13 nmol min(-1 mg(-1 for PPi, to 56 ± 11 nmol min(-1 mg(-1 for AMP, to 79 ± 23 nmol min(-1 mg(-1 for beta-glycerophosphate and to 73 ± 15 nmol min(-1 mg(-1 for 1-alpha-D glucose phosphate. The assay was also effective to monitor phosphatase activity in primary osteoblasts and in matrix vesicles. The use of levamisole--a TNAP inhibitor--served to demonstrate that a part of the phosphatase activity originated from this enzyme. An IC50 value of 1.16 ± 0.03 mM was obtained for the inhibition of phosphatase activity of levamisole in osteoblast like cells. The infrared assay could be extended to determine any type of phosphatase activity in other cells. It may serve as a metabolomic tool to monitor an overall phosphatase activity including acid phosphatases or other related enzymes.

  11. Crosstalk between EGFR and integrin affects invasion and proliferation of gastric cancer cell line, SGC7901

    Directory of Open Access Journals (Sweden)

    Dan L

    2012-10-01

    Full Text Available Li Dan,1,* Ding Jian,2,* Lin Na,1 Wang Xiaozhong,1 1Digestive Department, the Union Hospital of Fujian Medical University, Fujian, People’s Republic of China; 2Digestive Department, the First Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian, People’s Republic of China*These authors contributed equally to this workBackground/objective: To investigate the crosstalk between epidermal growth factor receptor (EGFR and integrin-mediated signal transduction pathways in human gastric adenocarcinoma cells.Methods: EGF was used as a ligand of EGFR to stimulate the gastric adenocarcinoma cell, SGC7901. Signal molecules downstream of the integrin, FAK(Y397 and p130cas(Y410 phosphorylation, were measured by immunoprecipitation and western blot. Fibronectin (Fn was used as a ligand of integrin to stimulate the same cell line. Signal molecules downstream of EGFR and extracellular signal-regulated kinase (ERK general phosphorylation were also measured. Focal adhesion kinase (FAK small-interfering RNA was designed and transfected into SGC7901 cells to decrease the expression of FAK. Modified Boyden chambers and MTT assay were used to examine the effect of FAK inhibition on the invasiveness and proliferation of SGC7901.Results: EGF activated FAK(Y397 and p130cas(Y410 phosphorylation, while Fn activated ERK general phosphorylation. Inhibition of FAK expression decreased p130cas(Y410 phosphorylation activated by EGF and ERK general phosphorylation activated by Fn, also decreased the invasiveness and proliferation of SGC7901 cells activated by EGF or Fn.Conclusion: There is crosstalk between EGFR and integrin signal transduction. FAK may be a key cross point of the two signal pathways and acts as a potential target for human gastric cancer therapy.Keywords: gastric adenocarcinoma, epidermal growth factor receptor, integrin, focal adhesion kinase, crosstalk

  12. Chemovirotherapy for head and neck squamous cell carcinoma with EGFR-targeted and CD/UPRT-armed oncolytic measles virus.

    Science.gov (United States)

    Zaoui, K; Bossow, S; Grossardt, C; Leber, M F; Springfeld, C; Plinkert, P K; Kalle, C von; Ungerechts, G

    2012-03-01

    First-line treatment of recurrent and/or refractory head and neck squamous cell carcinoma (HNSCC) is based on platinum, 5-fluorouracil (5-FU) and the monoclonal antiEGFR antibody cetuximab. However, in most cases this chemoimmunotherapy does not cure the disease, and more than 50% of HNSCC patients are dying because of local recurrence of the tumors. In the majority of cases, HNSCC overexpress the epidermal growth factor receptor (EGFR), and its presence is associated with a poor outcome. In this study, we engineered an EGFR-targeted oncolytic measles virus (MV), armed with the bifunctional enzyme cytosine deaminase/uracil phosphoribosyltransferase (CD/UPRT). CD/UPRT converts 5-fluorocytosine (5-FC) into the chemotherapeutic 5-FU, a mainstay of HNSCC chemotherapy. This virus efficiently replicates in and lyses primary HNSCC cells in vitro. Arming with CD/UPRT mediates efficient prodrug activation with high bystander killing of non-infected tumor cells. In mice bearing primary HNSCC xenografts, intratumoral administration of MV-antiEGFR resulted in statistically significant tumor growth delay and prolongation of survival. Importantly, combination with 5-FC is superior to virus-only treatment leading to significant tumor growth inhibition. Thus, chemovirotherapy with EGFR-targeted and CD/UPRT-armed MV is highly efficacious in preclinical settings with direct translational implications for a planned Phase I clinical trial of MV for locoregional treatment of HNSCC.

  13. Protein determination in soya bean by fast neutron activation analysis

    International Nuclear Information System (INIS)

    Szegedi, S.; Mosbah, D.S.; Varadi, M.; Szaloki, I.

    1988-01-01

    For a non-destructive determination of the protein content in soya bean samples, 14-MeV neutron activation analysis was applied. To check the method, the results obtained by X-ray fluorescence analysis and the Kjeldahl procedure were compared. For pressed pellet samples of about 1 g with 15 min irradiation and 10 min measuring times the accuracy of the protein determination was found to be 15%. (author) 7 refs.; 4 figs.; 3 tabs

  14. Neutron activation determination of rhenium in shales shales and molybdenites

    International Nuclear Information System (INIS)

    Zajtsev, E.I.; Radinovich, B.S.

    1977-01-01

    Described is the technique for neutron activation determination of rhenium in shales and molybdenites with its radiochemical extraction separation by methyl-ethyl ketone. The sensitivity of the analysis is 5x10 -7 %. Experimental checking of the developed technique in reference to the analysis of shales and molybdenites was carried out. Estimated is the possibility of application of X-ray gamma-spectrometer to instrumental determination of rhenium in molybdenites

  15. Determination of platinum concentration in gold matrix by neutron activation

    International Nuclear Information System (INIS)

    Cojocaru, V.; Spiridon, S.

    1985-01-01

    A comparative study was made of the neutron activation technique and atomic absorption spectrometry applied for the analysis of high purity Bi 2 O 3 and PbCl 2 . The study showed that in most cases NAA is sensitive enough to give reliable results. Atomic absorption spectroscopy was preferable for some elements which cannot be determined by NAA due to high matrice activity. So the combination of the two methods proved very successful and permits the determination of more than 20 elements. Additionally this approach enabled to control the accuracy of the method by comparison of the results obtained

  16. Determination of mercury in food by neutron activation

    International Nuclear Information System (INIS)

    Anand, S.J.S.

    1976-01-01

    Determination of mercury in food samples has been carried out by neutron activation followed by chemical separation to remove the interfering activities of copper, zinc etc. Chemical separation was carried out using anion exchange resin (DOWEX 1x8). Mercury was determined by counting 77 keV γ-rays of 197 Hg on a NaI(Tl) crystal in conjunction with a 400-channel pulse-height analyser. Levels of mercury in the following foods are tabulated: rice, wheat, pulses, millets, leafy vegetables, flower, carrot, potato, tomato, onion, chilli powder, sugar, tea leaves, milk. (T.I.)

  17. Determination of mercury in food by neutron activation

    Energy Technology Data Exchange (ETDEWEB)

    Anand, S J.S. [Bhabha Atomic Research Centre, Bombay (India). Air Monitoring Section

    1976-01-01

    Determination of mercury in food samples has been carried out by neutron activation followed by chemical separation to remove the interfering activities of copper, zinc etc. Chemical separation was carried out using anion exchange resin (DOWEX 1x8). Mercury was determined by counting 77 keV ..gamma..-rays of /sup 197/Hg on a NaI(Tl) crystal in conjunction with a 400-channel pulse-height analyser. Levels of mercury in the following foods are tabulated: rice, wheat, pulses, millets, leafy vegetables, flower, carrot, potato, tomato, onion, chilli powder, sugar, tea leaves, milk.

  18. DETERMINANTS OF LEISURE-TIME PHYSICAL ACTIVITY: EVIDENCE FROM MALAYSIA

    OpenAIRE

    YONG KANG CHEAH; ANDREW K. G. TAN

    2014-01-01

    This paper examines how socio-demographic and health-lifestyle factors determine participation and duration of leisure-time physical activity in Malaysia. Based on the Malaysia Non-Communicable Disease Surveillance-1 data, Heckman's sample selection model is employed to estimate the probability to participate and duration on physical activity. Results indicate that gender, age, years of education and family illness history are significant in explaining participation probability in leisure-tim...

  19. Determinants of physical activity frequency and provider advice during pregnancy.

    Science.gov (United States)

    Santo, Eilann C; Forbes, Peter W; Oken, Emily; Belfort, Mandy B

    2017-09-05

    Our aims were to (1) describe the frequency of physical activity and prenatal healthcare provider advice about physical activity during pregnancy and (2) examine determinants and correlates of 3rd trimester physical activity and receipt of physical activity advice. We analyzed data from the 2008 Pregnancy Risk Assessment Monitoring System. We studied 2669 women from North Carolina and Colorado with data on physical activity frequency in the 3 months prior to pregnancy and during the 3rd trimester and 1584 women from Oklahoma with data on provider advice regarding physical activity during pregnancy. Respondents reported physical activity, defined as 30 min or more of exercise/physical activity (excluding vocationally related activity), in in these categories: pregnancy was strongly associated with low likelihood of ACOG guideline adherence in the 3rd trimester (aOR 0.10, 95% CU 0.04, 0.30 vs. 1-4 days/week). Underweight women were more likely to adhere to ACOG guidelines than normal weight women (aOR 2.27, 95% CI 1.36, 3.79). Overweight women were more likely to receive physical activity advice (aOR 2.9, 95% CI 1.3, 6.3 vs. normal weight), but obese women were not (aOR 0.65, 95% CI 0.4, 1.2). Few women meet ACOG guideline criteria for physical activity during pregnancy. Improving physical activity and weight status prior to pregnancy may improve activity levels during pregnancy. Nearly one third did not receive advice about physical activity during prenatal care. Obese women were no more likely to receive advice than their normal weight counterparts, indicating the need for targeted physical activity counseling in this population.

  20. Simultaneous determination of aluminium and phosphorus by neutron activation analysis

    International Nuclear Information System (INIS)

    Gatschke, W.; Gawlik, D.

    1980-01-01

    With the use of the pneumatic tube system of the BER II reactor, the irradiation position of which is equipped with a movable cadmium shield, the aluminium and phosphorus levels in bone powder and in human bone biopsies were determined. The contribution of aluminium and phosphorus to the 28 Al activity could be separated mathematically after the samples had been irradiated with and without cadmium shielding. The sensitivity and limit of quantitative determination of the analytical procedure were determined using the addition method and the fact that the levels of each element measured was independent of the amount of the other element was proved. (author)

  1. Mercury determination in natural waters using neutron activation analysis

    International Nuclear Information System (INIS)

    Cagnone, M.; Marques, R.O.

    1994-01-01

    Available as short communication only. An analytical method for quantitative determination of Mercury traces in river and sea water is proposed. The neutron activation method and radiochemical separation of Mercury by developing of C L 4 Hg -2 complex, and their chromatographic separation using anionic exchange resin Dowex 1 X 8 of 400 mesh is used. The quantitative determination is done by gamma spectrometric analysis. The selection limits reached with this method showed that this is an amenable procedure in routine mercury determination in the ppb level, specially useful in the environmental contamination analysis. (author). 3 refs, 2 figs, 1 tab

  2. Gefitinib-induced killing of NSCLC cell lines expressing mutant EGFR requires BIM and can be enhanced by BH3 mimetics.

    Directory of Open Access Journals (Sweden)

    Mark S Cragg

    2007-10-01

    Full Text Available The epidermal growth factor receptor (EGFR plays a critical role in the control of cellular proliferation, differentiation, and survival. Abnormalities in EGF-EGFR signaling, such as mutations that render the EGFR hyperactive or cause overexpression of the wild-type receptor, have been found in a broad range of cancers, including carcinomas of the lung, breast, and colon. EGFR inhibitors such as gefitinib have proven successful in the treatment of certain cancers, particularly non-small cell lung cancers (NSCLCs harboring activating mutations within the EGFR gene, but the molecular mechanisms leading to tumor regression remain unknown. Therefore, we wished to delineate these mechanisms.We performed biochemical and genetic studies to investigate the mechanisms by which inhibitors of EGFR tyrosine kinase activity, such as gefitinib, inhibit the growth of human NSCLCs. We found that gefitinib triggered intrinsic (also called "mitochondrial" apoptosis signaling, involving the activation of BAX and mitochondrial release of cytochrome c, ultimately unleashing the caspase cascade. Gefitinib caused a rapid increase in the level of the proapoptotic BH3-only protein BIM (also called BCL2-like 11 through both transcriptional and post-translational mechanisms. Experiments with pharmacological inhibitors indicated that blockade of MEK-ERK1/2 (mitogen-activated protein kinase kinase-extracellular signal-regulated protein kinase 1/2 signaling, but not blockade of PI3K (phosphatidylinositol 3-kinase, JNK (c-Jun N-terminal kinase or mitogen-activated protein kinase 8, or AKT (protein kinase B, was critical for BIM activation. Using RNA interference, we demonstrated that BIM is essential for gefitinib-induced killing of NSCLC cells. Moreover, we found that gefitinib-induced apoptosis is enhanced by addition of the BH3 mimetic ABT-737.Inhibitors of the EGFR tyrosine kinase have proven useful in the therapy of certain cancers, in particular NSCLCs possessing

  3. EGFR and EGFRvIII Promote Angiogenesis and Cell Invasion in Glioblastoma: Combination Therapies for an Effective Treatment

    Directory of Open Access Journals (Sweden)

    Stefanie Keller

    2017-06-01

    Full Text Available Epidermal growth factor receptor (EGFR and the mutant EGFRvIII are major focal points in current concepts of targeted cancer therapy for glioblastoma multiforme (GBM, the most malignant primary brain tumor. The receptors participate in the key processes of tumor cell invasion and tumor-related angiogenesis and their upregulation correlates with the poor prognosis of glioma patients. Glioma cell invasion and increased angiogenesis share mechanisms of the degradation of the extracellular matrix (ECM through upregulation of ECM-degrading proteases as well as the activation of aberrant signaling pathways. This review describes the role of EGFR and EGFRvIII in those mechanisms which might offer new combined therapeutic approaches targeting EGFR or EGFRvIII together with drug treatments against proteases of the ECM or downstream signaling to increase the inhibitory effects of mono-therapies.

  4. EGFR testing and clinical management of advanced NSCLC: a Galician Lung Cancer Group study (GGCP 048-10

    Directory of Open Access Journals (Sweden)

    Vázquez S

    2016-02-01

    %, respectively. All but two patients received gefitinib. Median progression-free survival and overall survival were 10 (95% confidence interval: 4.8–15.3 months and 17.8 (95% confidence interval: 13.9–21.6 months, respectively, in patients carrying sensitizing mutations. Conclusion: The incidence of EGFR mutations in Galicia is consistent with previous data in Spain. Our results also support the feasibility of EGFR testing to guide treatment decision making using tumor tissue or cytology samples, or serum samples if tumor specimens are unavailable. These findings also confirm that first-line gefitinib is an active treatment option in Caucasians with EGFR mutation-positive NSCLC. Keywords: epidermal growth factor receptor, EGFR tyrosine inhibitors, TKIs, EGFR gene mutation, EGFR mutation testing, non-small-cell lung cancer

  5. Determining and Accounting of Fair Value in Agricultural Activities

    Directory of Open Access Journals (Sweden)

    Ahmet GÖKGÖZ

    2012-12-01

    Full Text Available Biological assets and agricultural products bring about the subject of agricultural production. Having biological transformation of biological assets and agricultural products via the cases such as growth, reproduction, deterioration, decay; makes the valuation of agricultural activities important. The Fair Value Approach is adopted in TAS 41, the Agricultural Activities Standard regulating agricultural activities, about the valuation of biological assets and agricultural products. In the study; determining process of biological assets and agricultural products’ fair value adopted by TAS 41 is explained. Afterwards; recording of increase and decrease, occured due to the valuation by the framework of TAS 41, through the accounts offered to the Uniform Chart of Accounts.

  6. Osimertinib and Necitumumab in Treating Patients With EGFR-Mutant Stage IV or Recurrent Non-small Cell Lung Cancer Who Have Progressed on a Previous EGFR Tyrosine Kinase Inhibitor

    Science.gov (United States)

    2018-03-07

    EGFR Exon 19 Deletion Mutation; EGFR Exon 20 Insertion Mutation; EGFR NP_005219.2:p.G719X; EGFR NP_005219.2:p.L858R; EGFR NP_005219.2:p.L861Q; EGFR NP_005219.2:p.T790M; EGFR T790M Mutation Negative; Recurrent Non-Small Cell Lung Carcinoma; Stage IV Non-Small Cell Lung Cancer AJCC v7

  7. Radiosensitivity and TP 53, EGFR amplification and LOH10 analysis of primary glioma cell cultures

    International Nuclear Information System (INIS)

    Gerlach, B.; Harder, A.H.; Slotman, B.J.; Sminia, P.; Hulsebos, T.J.M.; Leenstra, S.; Peter Vandertop, W.; Hartmann, K.A.

    2002-01-01

    Aim: Determination of in-vitro radiosensitivity and genetic alterations of cell cultures derived from human glioma biopsy tissue and established glioma cell lines. Material and Methods: Fresh brain tumor specimens of six patients were processed to early passage cell cultures. In addition the cell lines D 384 and Gli 6 were used. Cell cultures were irradiated with doses from 2 to 10 Gy. Following irradiation, cell survival was determined by clonogenic assay and survival curves were generated. The surviving fractions after 2 Gy (SF2) and 4 Gy (SF4) were used as radiosensitivity parameters. Genetic analysis included determination of the mutational and loss of heterozygosity (LOH) status of TP 53 (exons 5-8), the LOH 10- and epidermal growth factor receptor gene (EGFR) amplification status. Results: The SF2 and SF4 values ranged from 0.54 to 0.88 (mean: 0.70) and from 0.13 to 0.52 (mean: 0.32), respectively. Genetic alterations were found in the Gli 6 cell line and in two primary cell cultures. The genetic profile of Gli 6 showed LOH but no TP 53 mutation, complete LOH 10 and no EGFR amplification. The VU 15 cell culture showed TP 53 mutation but no LOH 10 or EGFR amplification, while VU 24 showed incomplete LOH 10, EGFR amplification and no TP 53 mutation. In the other four cell cultures and D 384 cell line no genetic alterations were diagnosed. Histopathological classification of glioblastoma multiforme and/or genetic alterations resulted in lower radiosensitivity. Conclusion: In this small series of early passage glioma cell cultures low radiosensitivity and alterations in cell regulatory genes were seen. Further testing of biological behavior in larger series of patient-derived material is ongoing. (orig.)

  8. The application of different techniques to determine activated sludge ...

    African Journals Online (AJOL)

    The application of different techniques to determine activated sludge kinetic parameters in a food industry wastewater. ... method) and a respirometric technique based on oxygen consumption measurements, were used to compare microbial parameters using a wastewater model system of a potato processing plant.

  9. Physical Activity And Dietary Fat As Determinants Of Body Mass ...

    African Journals Online (AJOL)

    Overweight/obesity and related disease conditions will constitute a major threat to the economically productive adults and subsequently, will present a huge health-care burden on developing countries in the near future. Suspected determinants include physical activity and dietary fat. The main indicator of ...

  10. The Determinants of Participation in Physical Activity in Malaysia

    Science.gov (United States)

    Cheah, Yong Kang; Poh, Bee Koon

    2014-01-01

    Objectives In light of the importance of physical activity, the aim of the present study is to examine the factors affecting participation in physical activity among adults in Malaysia. Methods A logistic regression model and the Third National Health and Morbidity Survey consisting of 30,992 respondents were used. Results Age, income, gender, education, marital status, region, house locality, job characteristics, and medical conditions are significantly associated with participation in physical activity. In particular, old individuals, high income earners, females, the well-educated, widowed or divorced individuals, East Malaysians, urban dwellers, the unemployed, and individuals who are not diagnosed with hypercholesterolemia are less likely to be physically active than others. Conclusion Because sociodemographic and health factors play an important role in determining physical activity, the government should take them into account when formulating policy. PMID:24955308

  11. Identifying EGFR-Expressed Cells and Detecting EGFR Multi-Mutations at Single-Cell Level by Microfluidic Chip

    Science.gov (United States)

    Li, Ren; Zhou, Mingxing; Li, Jine; Wang, Zihua; Zhang, Weikai; Yue, Chunyan; Ma, Yan; Peng, Hailin; Wei, Zewen; Hu, Zhiyuan

    2018-03-01

    EGFR mutations companion diagnostics have been proved to be crucial for the efficacy of tyrosine kinase inhibitor targeted cancer therapies. To uncover multiple mutations occurred in minority of EGFR-mutated cells, which may be covered by the noises from majority of un-mutated cells, is currently becoming an urgent clinical requirement. Here we present the validation of a microfluidic-chip-based method for detecting EGFR multi-mutations at single-cell level. By trapping and immunofluorescently imaging single cells in specifically designed silicon microwells, the EGFR-expressed cells were easily identified. By in situ lysing single cells, the cell lysates of EGFR-expressed cells were retrieved without cross-contamination. Benefited from excluding the noise from cells without EGFR expression, the simple and cost-effective Sanger's sequencing, but not the expensive deep sequencing of the whole cell population, was used to discover multi-mutations. We verified the new method with precisely discovering three most important EGFR drug-related mutations from a sample in which EGFR-mutated cells only account for a small percentage of whole cell population. The microfluidic chip is capable of discovering not only the existence of specific EGFR multi-mutations, but also other valuable single-cell-level information: on which specific cells the mutations occurred, or whether different mutations coexist on the same cells. This microfluidic chip constitutes a promising method to promote simple and cost-effective Sanger's sequencing to be a routine test before performing targeted cancer therapy.[Figure not available: see fulltext.

  12. Phase I/II clinical and pharmacokinetic study evaluating a fully human monoclonal antibody against EGFr (HuMax-EGFr) in patients with advanced squamous cell carcinoma of the head and neck

    DEFF Research Database (Denmark)

    Bastholt, Lars; Specht, Lena; Jensen, Kenneth

    2007-01-01

    PURPOSE: To assess safety, tolerability, pharmacokinetics and clinical activity of HuMax-EGFr in patients with SCCHN. PATIENTS AND METHODS: Twenty-eight patients with SCCHN were enrolled. The study comprised a single-dose escalation part for assessment of safety issues followed by a repeat dose e...

  13. Determination of chromium in biological matrices by neutron activation

    International Nuclear Information System (INIS)

    McClendon, L.T.

    1978-01-01

    Chromium is recognized to be an essential trace element in several biological systems. It exists in many biological materials in a variety of chemical forms and very low concentration levels which cause problems for many analytical techniques. Both instrumental and destructive neutron activation analysis were used to determine the chromium concentration in Orchard Leaves, SRM 1571, Brewers Yeast, SRM 1569, and Bovine Liver, SRM 1577. Some of the problems inherent with determining chromium in certain biological matrices and the data obtained here at the National Bureau of Standards using this technique are discussed. The results obtained from dissolution of brewers yeast in a closed system as described in the DNAA procedure are in good agreement with the INAA results. The same phenomenon existed in the determination of chromium in bovine liver. The radiochemical procedure described for chromium (DNAA) provides the analyst with a simple, rapid and selective technique for chromium determination in a variety of matrices. (T.G.)

  14. Statistical Analysis of EGFR Structures’ Performance in Virtual Screening

    Science.gov (United States)

    Li, Yan; Li, Xiang; Dong, Zigang

    2015-01-01

    In this work the ability of EGFR structures to distinguish true inhibitors from decoys in docking and MM-PBSA is assessed by statistical procedures. The docking performance depends critically on the receptor conformation and bound state. The enrichment of known inhibitors is well correlated with the difference between EGFR structures rather than the bound-ligand property. The optimal structures for virtual screening can be selected based purely on the complex information. And the mixed combination of distinct EGFR conformations is recommended for ensemble docking. In MM-PBSA, a variety of EGFR structures have identically good performance in the scoring and ranking of known inhibitors, indicating that the choice of the receptor structure has little effect on the screening. PMID:26476847

  15. Determination of β-activity of foodstuffs and menus

    International Nuclear Information System (INIS)

    Cieleszky, V.; Czegledi, P.; Tarjan, R.; Dobrovolszky, A.; Hapka, S.

    1974-01-01

    The total β and potassium activities of a lot of foodstuffs and menus have been determined. The average remaining β-activities were as follows: 33 pCi/100 g for vegetables; 132 pCi/100 g for wheat samples; 154 pCi/100 g for rye; 47-52 pCi/100 g for meat; 115 pCi/100 g for fish. The rest β-activity was max. 119 pCi/100 g (rasberry mash) for baby-conserves and 1120 pCi/100 g (Indian tea) for the examined import foodstuffs. The average daily intake of artificial β-activity by foods is in the range of 1000 pCi. (K.A.)

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

    OpenAIRE

    Choudhary, Kumari Sonal; Rohatgi, Neha; Halldorsson, Skarphedinn; Briem, Eirikur; Gudjonsson, Thorarinn; Gudmundsson, Steinn; Rolfsson, Ottar

    2016-01-01

    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 modelli...

  17. Icotinib (BPI-2009H), a novel EGFR tyrosine kinase inhibitor, displays potent efficacy in preclinical studies.

    Science.gov (United States)

    Tan, Fenlai; Shen, Xiaoyan; Wang, Dechang; Xie, Guojian; Zhang, Xiaodong; Ding, Lieming; Hu, Yunyan; He, Wei; Wang, Yanping; Wang, Yinxiang

    2012-05-01

    Icotinib, one of the leading compounds selected from our compound library, was found to be a potent and specific epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) with an IC(50) of 5 nM. When profiled with 88 kinases, Icotinib only showed meaningful inhibitory activity to EGFR and its mutants. Icotinib blocked EGFR-mediated intracellular tyrosine phosphorylation (IC(50)=45 nM) in the human epidermoid carcinoma A431 cell line and inhibits tumor cell proliferation. In vivo studies demonstrated that Icotinib exhibited potent dose-dependent antitumor effects in nude mice carrying a variety of human tumor-derived xenografts. The drug was well tolerated at doses up to 120 mg/kg/day in mice without mortality or significant body weight loss during the treatment. A head to head randomized, double blind phase III trial using Gefitinib as an active control for patients with advanced non-small cell lung cancer (NSCLC) was finished recently (Trial registration ID: NCT01040780). The data shows that Icotinib was non-inferior to Gefitinib in terms of median progression free survival (PFS) and safety superior favor to Icotinib compared to Gefitinib. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  18. Determinants of clean development mechanism activity: Evidence from China

    International Nuclear Information System (INIS)

    Xie, Huiming; Shen, Manhong; Wang, Rui

    2014-01-01

    As regards the dual goals of additionality and sustainability, some clean development mechanism (CDM) projects were successfully registered while some were rejected by the Executive Board (EB). This paper focuses on two final statuses of these projects and aims to explore the potential determinants of CDM activities. Based on the Chinese samples of the rejections and registrations, we find that (1) according to the financial barrier analysis with the internal rate of return without CDM, the additionality is the most important and robust rule of CDM activities and the CDM projects successfully registered are more additional than the rejected ones in China; (2) the sustainability is another important determinant of CDM activities in China and Chinese CDM activities are sustainable in terms of size, while the EB is criticized for its selection of unsustainable CDM projects in terms of cost-effectiveness on emission reductions within a long period or in terms of hydropower plants; (3) some other factors including the prices of sale electricity and certified emission reductions, the generating capacity and installed capacity all tend to pose significant impacts on the final status of each project that features the CDM activities in local areas of China. - Highlights: • The final status of each project features the CDM activities in local areas. • Microeconomic factors have significant impacts on the final statuses. • The additionality is the most important and robust rule of CDM activities in China. • Chinese CDM activities are sustainable in terms of size. • Chinese unsustainable CDM projects were selected by the EB in terms of cost-effectiveness

  19. Erlotinib Versus Radiation Therapy for Brain Metastases in Patients With EGFR-Mutant Lung Adenocarcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Gerber, Naamit K.; Yamada, Yoshiya; Rimner, Andreas [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Shi, Weiji [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Riely, Gregory J. [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Beal, Kathryn [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Yu, Helena A. [Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Chan, Timothy A. [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Zhang, Zhigang [Department of Epidemiology and Biostatistics, Memorial Sloan-Kettering Cancer Center, New York, New York (United States); Wu, Abraham J., E-mail: wua@mskcc.org [Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York (United States)

    2014-06-01

    Purpose/Objectives: Radiation therapy (RT) is the principal modality in the treatment of patients with brain metastases (BM). However, given the activity of EGFR tyrosine kinase inhibitors in the central nervous system, it is uncertain whether upfront brain RT is necessary for patients with EGFR-mutant lung adenocarcinoma with BM. Methods and Materials: Patients with EGFR-mutant lung adenocarcinoma and newly diagnosed BM were identified. Results: 222 patients were identified. Exclusion criteria included prior erlotinib use, presence of a de novo erlotinib resistance mutation, or incomplete data. Of the remaining 110 patients, 63 were treated with erlotinib, 32 with whole brain RT (WBRT), and 15 with stereotactic radiosurgery (SRS). The median overall survival (OS) for the whole cohort was 33 months. There was no significant difference in OS between the WBRT and erlotinib groups (median, 35 vs 26 months; P=.62), whereas patients treated with SRS had a longer OS than did those in the erlotinib group (median, 64 months; P=.004). The median time to intracranial progression was 17 months. There was a longer time to intracranial progression in patients who received WBRT than in those who received erlotinib upfront (median, 24 vs 16 months, P=.04). Patients in the erlotinib or SRS group were more likely to experience intracranial failure as a component of first failure, whereas WBRT patients were more likely to experience failure outside the brain (P=.004). Conclusions: The survival of patients with EGFR-mutant adenocarcinoma with BM is notably long, whether they receive upfront erlotinib or brain RT. We observed longer intracranial control with WBRT, even though the WBRT patients had a higher burden of intracranial disease. Despite the equivalent survival between the WBRT and erlotinib group, this study underscores the role of WBRT in producing durable intracranial control in comparison with a targeted biologic agent with known central nervous system activity.

  20. Determination of mercury in dentists through Neutron activation analysis

    International Nuclear Information System (INIS)

    Padilla M, M.A.; Granados C, F.

    1999-01-01

    It was determined the mercury levels in urine through Neutron activation analysis to 25 dentists who have been exposed to mercury by several time periods, because of the routine manipulations of amalgams. The determined concentrations of mercury were less to 10 μ g Hg/l of urine. The results were founded inside the safety limits reported in the literature. The mercury levels in the dentists are associated with a wide variety of factors that contribute to their exposure as: number of years of dental practice, number of amalgams manipulated between others. (Author)

  1. EGFR signaling in colorectal cancer: a clinical perspective

    Directory of Open Access Journals (Sweden)

    Saletti P

    2015-01-01

    Full Text Available Piercarlo Saletti,1 Francesca Molinari,2 Sara De Dosso,1 Milo Frattini2 1Oncology Institute of Southern Switzerland, Bellinzona, 2Laboratory of Molecular Pathology, Institute of Pathology, Locarno, Switzerland Abstract: Colorectal cancer (CRC remains a formidable health burden worldwide, with up to 50% of patients developing metastases during the course of their disease. This group of CRC patients, characterized by the worst prognosis, has been extensively investigated to improve their life expectancy. Main efforts, focused on the epidermal growth-factor receptor (EGFR, which plays a pivotal role in CRC pathogenesis, have led to the development and introduction in clinical practice of specific targeted therapies (ie, monoclonal antibodies. Subsequently, the scientific community has tried to identify molecular predictors of the efficacy of such therapies. However, it has become clear that EGFR alterations occurring in CRC are difficult to investigate, and therefore their predictive role is unclear. In contrast, the clinical role of two downstream members (KRAS and NRAS has been clearly demonstrated. Currently, EGFR-targeted therapies can be administered only to patients with wild-type KRAS and NRAS genes. Our review addresses the medical management of metastatic CRC. Specifically, we describe in detail the molecular biology of metastatic CRC, focusing on the EGFR signaling pathway, and we discuss the role of current and emerging related biomarkers and therapies in this field. We also summarize the clinical evidence regarding anti-EGFR monoclonal antibodies and examine potential future perspectives. Keywords: colorectal cancer, EGFR, gene mutations, cetuximab, panitumumab

  2. Determination of ultraviolet filter activity on coconut oil cosmetic cream

    Science.gov (United States)

    Widiyati, Eni

    2017-08-01

    A research on determination of ultraviolet (UV) filter activity of cosmetic cream with coconut oil as raw material has been done. The cream was made by mixing the oil phase (coconut oil, stearic acid, lanolin and cetyl alcohol) at 70°C and the water phase (glycerin, aquadest and triethanolamine) at 70°C, while stirring until reached a temperature of 35°C. It was made also a cream with inorganic sunscreen TiO2 and organic sunscreen benzophenone-3 as a comparison. To study the UV filter activity, each cream was determined the UV absorption using UV spectrophotometer. The results show that cosmetic cream with coconut oil as raw material absorbs UV rays in the region of UV-C, whereas the cream with TiO2 absorbs the UV rays from UV-C to UV-A and cream with benzophenone-3 absorbs the UV rays from UV-B to UV-A region. This means that, the cosmetic cream with coconut oil as raw material has an activity as UV-C filter. If this cream is expected to have an activity as a sunscreen, it must be added an inorganic or organic sunscreen or a mixture of both as an active materials.

  3. Determination of silver using cyclic epithermal neutron activation analysis

    International Nuclear Information System (INIS)

    Pun, T.H.; Landsberger, S.

    2012-01-01

    A fast pneumatic transfer facility was installed in Nuclear Engineering Teaching Laboratory (NETL) of the University of Texas at Austin for the purpose of cyclic thermal and epithermal neutron activation analysis. In this study efforts were focused on the evaluation of cyclic epithermal neutron activation analysis (CENAA). Various NIST and CANMET certified materials were analyzed by the system. Experiment results showed 110 Ag with its 25 s half-life as one of the isotopes favored by the system. Thus, the system was put into practical application in identifying silver in metallic ores. Comparison of sliver concentrations as determined by CENAA in CANMET certified reference materials gave very good results. (author)

  4. Vanadium determination in pretoleum by neutron activation analysis

    International Nuclear Information System (INIS)

    Lopez, M.; Espinosa, R.

    1983-01-01

    The vanadium concentration in an Peruvian petroleum sample is determined by neutron activation analysis. The samples were irradiated for 20 minutes with a flux of thermal neutrons of 1.75 x 10 7 n/cm 2 -s in a subcritical assembly. The activity of the created samples decreases to half 15 minutes after the irradiation. The result is 28.3 +- 0.8 p.p.m. with a typical deviation of 2.8%. The detection limit of this method is 4 p.p.m

  5. 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...... this NCAM-180-induced EGFR down-regulation involves increased EGFR ubiquitination and lysosomal EGFR degradation. Furthermore, NCAM-180-mediated EGFR down-regulation requires NCAM homophilic binding and interactions of the cytoplasmic domain of NCAM-180 with intracellular interaction partners, but does...

  6. Calcium determination in bone by proton activation analysis. Progress report

    International Nuclear Information System (INIS)

    Wilson, R.; Adelstein, S.

    1974-01-01

    The incidence of post-menopausal osteoporosis in almost epidemic proportions makes the early diagnosis and development of effective therapy a matter of considerable concern. Current status of the project is reviewed and new applications of calcium determination by in vivo proton activation analysis are discussed. The proton activation method promises to give precise and reproducible measurements of calcium content for a single vertebra or several vertebrae in vivo. By controlling the number and energy of protons incident on a vertebra and by accurately detecting the number of 2.17 MeV gamma rays emitted, one may determine the 40Ca content. The proton technique offers advantages by directly measuring calcium in a very well-defined region. On-going studies by the construction of a lead shield for in vivo counting and for the analysis of the results are also given

  7. Neutron activation determination of phosphorus in semiconductor materials

    International Nuclear Information System (INIS)

    Verevkin, G.V.; Gil'bert, Eh.N.; Gol'dshtejn, M.M.; Yudelevich, I.G.; Yurchenko, V.K.

    1976-01-01

    The solvent extraction of molybdophosphoric acid (MPA) with benzene and dichloroethane solutions of dioctylsulphoxide has been studied. A neutron-activation method has been worked out of determining phosphorus in semiconductor silicon, high purity gallium, and homoepitaxial films of gallium arsenide. The method is based on separation of radiochemically pure phosphorus in the form of MPA by extraction with 0.2 M solution of dioctylsulphoxide in benzene and measurement of 32 P activity on a liquid scintillation spectrometer. The method makes it possible to determine phosphorus in the materials enumerated with a limit of detection of 1.9x10 -10 g and a relative standard deviation of not more than 0.05

  8. Determination of sodium in pharmaceuticals by neutron activation analysis

    International Nuclear Information System (INIS)

    Kanias, G.D.

    1985-01-01

    A simple, fast and accurate neutron activation analysis method for determination of Na in drugs concerning either active compound or total content was developed. The examined dosage forms consisted of 10 injectable ampoules and 10 bottles of oral solutions. The irradiation of samples and standards was carried out in the rotation system of the Reactor of Nuclear Research Center Democritos with maximal neutron flux of 2,9.10 13 n.cm -2 .sec -1 . Gamma-ray spectrometry of the irradiated samples and standards was accomplished with a coaxial Ge(Li) detector series Win 15 with an efficiency of 15% connected to an Ino-Tech 1024 channel analyser (Model IT 5200). The accuracy and precision of the method are found to be very high and therefore it could be established as an official one for the determination of sodium in parmaceuticals

  9. Limitations of absolute activity determination of I-125 sources

    Energy Technology Data Exchange (ETDEWEB)

    Pelled, O; German, U; Kol, R; Levinson, S; Weinstein, M; Laichter, Y [Israel Atomic Energy Commission, Beersheba (Israel). Nuclear Research Center-Negev; Alphasy, Z [Ben-Gurion Univ. of the Negev, Beersheba (Israel)

    1996-12-01

    A method for absolute determination of the activity of a I-125 source, based on the counting rate values of the 27 keV photons and the coincidence photon peak is given in the literature. It is based on the principle that if a radionuclide emits two photons in coincidence , a measurement of its disintegration rate in the photopeak and in the sum- peak can determinate it`s absolute activity. When using this method , the system calibration is simplified and parameters such as source geometry or source position relative to the detector have no significant influence. However, when the coincidence rate is very low, the application of this method is limited because of the statistics of the coincidence peak (authors).

  10. DETERMINATION OF ANTIMICROBIAL ACTIVITY OF EXTRACTS OF CALENDULA OFFICINALIS FLOWERS

    Directory of Open Access Journals (Sweden)

    P. V. Afanasyeva

    2016-01-01

    Full Text Available Pot marigold (Calendula officinalis L. is one of the most popular medicinal plants in the Russian Federation and abroad. The wide range of pharmacological activity of this medicinal plant is determined by carotenoids, flavonoids, saponins. These biologically active substances give total therapeutic effect of flowers of Calendula officinalis and medicines on base of pot marigold. This paper discusses the results of comparative investigations for a determination of antimicrobial activity of aqueous and aqueous- alcoholic extracts from pot marigold flowers. Detection of the minimum inhibitory concentration (MIC was carried out by using the method of double serial dilutions in broth. The following microorganisms were used as test cultures: Bacillus cereus, Candida albicans, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. The study showed that the widest spectrum of antibacterial activity has water extract of pot marigold flowers. As for Pseudomonas aeruginosa the most active medicine is tincture (1:10 with 70% alcohol. As for Escherichia coli the only phytopharmaceutical – water extract of marigold flowers, reveals antimicrobial activity. Against Bacillus cereus the most effective properties was indicated for tincture (1:5 with 70% ethanol and the liquid extract (1:2 with 70% alcohol. In case of Candida albicans, tincture (1:10 with 70% alcohol exhibited the highest activity.

  11. Determination of 210Pb activity concentration in lead shielding

    International Nuclear Information System (INIS)

    Slivka, J.; Mrdja, D.; Varga, E.; Veskovic, M.

    2005-01-01

    210 Pb is concentrated during the separation lead from the ore and therefore it is the main pollutant of lead products. The content of this isotope limits the applicability of lead for low-level shielding of gamma spectrometers. In this paper, a new method for the determination of 210 Pb activity concentration in lead shielding from 46.5 keV gamma line intensity is presented. (author) [sr

  12. Development of freeze-dried kit for direct 99mTc -labeling of nimotuzumab to diagnose human EGFR positive tumors

    International Nuclear Information System (INIS)

    Toledo, Darien; Figueiras, Jenneby; Rojas, Gertrudis; León, Kalet; Gongora Bravo, Magdiel; Miguel Martínez, Antonio; Michel Alonso, Luis; Hernández, Ignacio; León, Mariela; Leyva, René; Hernández, Gerardo Ramses

    2016-01-01

    Epidermal growth factor receptor (EGFR), a 170 kDa transmembrane tyrosine kinase receptor which specifically binds epidermal growth factor (EGF) and transforming growth factor-a (TGFa) that are crucial in signaling cell proliferation, differentiation, and survival1. Overexpression of EGFR has been observed in breast cancer2, colorectal cancer, ovarian cancer, squamous cell lung carcinoma3 head and neck cancer4 and bladder cancer. Molecular imaging using radiopharmaceuticals directed towards EGFR could characterize the receptor status of tumors and thereby predict response to anti-EGFR agents for the treatment of cancer. Nimotuzumab is a humanized anti-EGFR monoclonal antibody5 designed to reduce immunogenicity and rate of clearance from the body6. Radiolabelled formulations of nimotuzumab would have applications for non-invasive imaging in order to characterize EGFR-positive tumors and thus to select patient populations that could benefit from therapy7, 8. The studies described in this work were designed to develop and evaluate the in vitro and in vivo the properties of a radiolabeled freeze dried kit of nimotuzumab and to determine its potential for radio immunodiagnostic applications. (author)

  13. ADCC responses and blocking of EGFR-mediated signaling and cell growth by combining the anti-EGFR antibodies imgatuzumab and cetuximab in NSCLC cells

    NARCIS (Netherlands)

    Kol, Arjan; Terwisscha van Scheltinga, Anton; Pool, Martin; Gerdes, Christian; de Vries, Elisabeth; de Jong, Steven

    2017-01-01

    Imgatuzumab is a novel glycoengineered anti-epidermal growth factor receptor (EGFR) monoclonal antibody optimized to induce both antibody-dependent cellular cytotoxicity (ADCC) and EGFR signal transduction inhibition. We investigated antiEGFR monoclonal antibodies imgatuzumab and cetuximab-induced

  14. Absolute activity determination of I-125 in the thyroid

    International Nuclear Information System (INIS)

    Peled, O; German, U.; Laichter, Y.

    1999-06-01

    In special cases were a radionuclide emits two photons in cascade, a sum-peak is created in the detector at energy which is the sum of the two single energies. In those cases, it is possible to use the Sum-Peak method in which the system calibration is simplified and parameters such as source geometry, source position relative to the detector and self-absorption can have no significant influence. The purpose of the present work was to check the range of the different parameters where the Sum-Peak method can be applied with good accuracy. The application of the method to determine the activity of I-125 in human thyroid is also presented. The measurements were performed with a Phoswich detector, which is part of a Whole Body Counter (WBC) system and with a standard 1mm. thick NaI(Tl) detector. For the following parameters range it is expected that the error of the activity determination, when using the Sum-Peak method, is up to 15% : activity up to 2000nCi, distance between the detector and the thyroid gland up to 7 cm, thyroid gland dimension up to 20cc . Using improved software that fits Gaussian functions to the spectrum can improve the range of the geometrical constraints and can reduce the error in the activity determination, when using the Sum-Peak method. However, when the coincidence rate is very low, the application of this method is limited because of the poor counting statistics in the coincidence peak. In those cases, the Personal Calibration factor can be used. Comparing the results obtained by using the Sum-Peak method on people to the results received when using the direct method (based on phantom calibration), we obtained a significant over estimation of the thyroid activity when using the direct method by a factor of 4 to 9, because this method can not compensate for the geometry differences between different persons and the calibration phantom

  15. Inhibitors of EGFR and PI3K/Akt/mtor pathways for the treatment of head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Navarro Palomares, E. M.

    2015-07-01

    Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and although new therapeutic approaches have been recently evaluated, improvement in overall patient survival is still poor. For this reason, new effective and selective clinical treatments are urgently needed. Genomic analysis allowing the identification of differences between normal and tumor cells provides new therapeutic options identifying novel targets or drugs that have shown efficacy in other tumor types. In this sense, EGFR amplification and/or overexpression are frequent events in HNSCC; in fact, the only targeted therapy approved to treat HNSCC is the anti-EFGR antibody Cetuximab. Based on cell line drug screening studies we identified Bosutinib (SKI-606), a Src/Abl inhibitor, as a candidate drug to treat HNSCC. Using a panel of HNSCC cell lines we found that the treatment with Bosutinib was able to reduce cell proliferation and to induce apoptosis at higher doses. We verified that the drug rapidly inhibited EGFR phosphorylation, and sensitivity to Bosutinib correlated with the activation of EGFR in tumor-derived cell lines. Moreover, Bosutinib showed a synergistic effect on cell viability with the PI3K? inhibitor BYL719 only in those cell lines with mutations in PIK3CA. These results suggest that Bosutinib could be a new effective drug in the treatment of HNSCC cancer, especially in tumors with high activity of EGFR, and its combination with BYL719 could especially benefit those patients bearing activating mutations of PIK3CA. (Author)

  16. 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.

  17. Role of [18F]FDG PET in prediction of KRAS and EGFR mutation status in patients with advanced non-small-cell lung cancer

    International Nuclear Information System (INIS)

    Caicedo, Carlos; Garcia-Velloso, Maria Jose; Vigil Diaz, Carmen; Richter Echevarria, Jose Angel; Lozano, Maria Dolores; Labiano, Tania; Lopez-Picazo, Jose Maria; Gurpide, Alfonso; Perez Gracia, Jose Luis; Zulueta, Javier

    2014-01-01

    The tumour molecular profile predicts the activity of epidermal growth factor receptor (EGFR) inhibitors in non-small-cell lung cancer (NSCLC). However, tissue availability and tumour heterogeneity limit its assessment. We evaluated whether [ 18 F]FDG PET might help predict KRAS and EFGR mutation status in NSCLC. Between January 2005 and October 2011, 340 NSCLC patients were tested for KRAS and EGFR mutation status. We identified patients with stage III and IV disease who had undergone [ 18 F]FDG PET/CT scanning for initial staging. SUVpeak, SUVmax and SUVmean of the single hottest tumour lesions were calculated, and their association with KRAS and EGFR mutation status was assessed. A receiver operator characteristic (ROC) curve analysis and a multivariate analysis (including SUVmean, gender, age and AJCC stage) were performed to identify the potential value of [ 18 F]FDG PET/CT for predicting KRAS mutation. From 102 patients staged using [ 18 F]FDG PET/CT, 28 (27 %) had KRAS mutation (KRAS+), 22 (22 %) had EGFR mutation (EGFR+) and 52 (51 %) had wild-type KRAS and EGFR profiles (WT). KRAS+ patients showed significantly higher [ 18 F]FDG uptake than EGFR+ and WT patients (SUVmean 9.5, 5.7 and 6.6, respectively; p 18 F]FDG uptake between EGFR+ patients and WT patients. ROC curve analysis for KRAS mutation status discrimination yielded an area under the curve of 0.740 for SUVmean (p 18 F]FDG uptake than WT patients, as assessed in terms of SUVpeak, SUVmax and SUVmean. A multivariate model based on age, gender, AJCC stage and SUVmean might be used as a predictive marker of KRAS mutation status in patients with stage III or IV NSCLC. (orig.)

  18. EGFR mutation is a better predictor of response to tyrosine kinase inhibitors in non-small cell lung carcinoma than FISH, CISH, and immunohistochemistry.

    Science.gov (United States)

    Sholl, Lynette M; Xiao, Yun; Joshi, Victoria; Yeap, Beow Y; Cioffredi, Leigh-Anne; Jackman, David M; Lee, Charles; Jänne, Pasi A; Lindeman, Neal I

    2010-06-01

    About 10% of patients with non-small cell lung carcinoma (NSCLC) respond to epidermal growth factor receptor (EGFR)-targeted tyrosine kinase inhibitors (TKIs). More than 75% of "responders" have activating mutations in EGFR. However, mutation analysis is not widely available, and proposed alternatives (in situ hybridization and immunohistochemical analysis) have shown inconsistent associations with outcome. Fluorescence in situ hybridization (FISH), chromogenic in situ hybridization (CISH), immunohistochemical analysis, and DNA sequencing were compared in this study of 40 NSCLC samples from TKI-treated patients. Response rates were 12 of 19 in EGFR-mutant vs 1 of 20 EGFR wild-type tumors (P = .0001), 7 of 19 FISH+ vs 4 of 17 FISH- tumors (not significant [NS]), 5 of 16 CISH+ vs 6 of 21 CISH- tumors (NS), and 3 of 9 immunohistochemically positive vs 7 of 22 immunohistochemically negative tumors (NS). EGFR mutation was associated with improved progression-free survival (P = .0004). Increased copy number (FISH or CISH) and protein expression (immunohistochemical) did not independently predict outcome. Thus, EGFR sequence analysis was the only method useful for predicting response and progression-free survival following TKI therapy in NSCLC.

  19. Determination of iodine 129 in vegetables using neutron activation analysis

    International Nuclear Information System (INIS)

    Quintana, Eduardo E.; Thyssen, Sandra M.; Bruno, Hector A.

    1999-01-01

    The developed methodology allows the determination of iodine 129 in vegetables, using neutron activation analysis. The chemical treatment removes the interferences present in these matrixes, as well as the bromine 82 originated in the activation process. The experimental method for the determination of iodine 129 by neutron activation analysis involves five steps: 1- digestion by alkaline fusion; 2- pre-irradiation purification of iodine 129 by distillation followed by solvent extraction, and adsorption on activated charcoal by distillation; 3- neutron irradiation; 4- post-irradiation purification of iodine 130 by distillation followed by solvent extraction; 5- gamma spectrometry. A chemical recovery of 95 % is obtained in the distillations, measured using iodine 131 as tracer. The whole process recovery is within 70 % and 85 %. The detection limit is 2 mBq/kg of sample, but several factors affect this value, such as type of vegetable, natural iodine concentration, irradiation time and neutron flux. The methodology developed is applied at environmental surveillance with safeguards proposes, in the detection of undeclared reprocessing of irradiated fuel. (authors)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-06-15

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

  1. Association of BIM Deletion Polymorphism and BIM-γ RNA Expression in NSCLC with EGFR Mutation.

    Science.gov (United States)

    Isobe, Kazutoshi; Kakimoto, Atsushi; Mikami, Tetsuo; Kaburaki, Kyohei; Kobayashi, Hiroshi; Yoshizawa, Takahiro; Makino, Takashi; Otsuka, Hajime; Sano, G O; Sugino, Keishi; Sakamoto, Susumu; Takai, Yujiro; Tochigi, Naobumi; Iyoda, Akira; Homma, Sakae

    This pilot study assessed the association of BIM deletion polymorphism and BIM RNA isoform in patients with EGFR-positive non-small cell lung cancer (NSCLC). The study included 33 patients with EGFR-positive NSCLC treated with gefitinib. BIM deletion polymorphism and BIM RNA isoform (EL/L/S/γ) were determined by polymerase chain reaction (PCR). BIM-γ expression was significantly higher in patients with BIM deletion polymorphism than among those without BIM deletion polymorphism inside tumors (p=0.038) and around tumors (p=0.0024). Relative BIM-γ expression was significantly higher in patients with BIM deletion polymorphism than among those without BIM deletion polymorphism (p=0.0017). Patients with BIM-γ had significantly shorter progression-free survival than those without BIM-γ (median: 304 vs. 732 days; p=0.023). Expression of BIM-γ mRNA and BIM deletion polymorphism were strongly associated. BIM-γ overexpression may have a role in apoptosis related to EGFR-tyrosine kinase inhibitor. Copyright© 2016, International Institute of Anticancer Research (Dr. John G. Delinasios), All rights reserved.

  2. EGFR mutations predict a favorable outcome for malignant pleural effusion of lung adenocarcinoma with Tarceva therapy.

    Science.gov (United States)

    Guo, Haisheng; Wan, Yunyan; Tian, Guangyan; Liu, Qinghua; Kang, Yanmeng; Li, Yuye; Yao, Zhouhong; Lin, Dianjie

    2012-03-01

    The aim of the present study was to evaluate the therapeutic effects and adverse reactions of Tarceva treatment for malignant pleural effusion (MPE) caused by metastatic lung adenocarcinomas. One hundred and twenty-eight patients who failed first-line chemotherapy drug treatment were divided into a mutation and a non-mutation group according to the presence or absence of epidermal growth factor receptor (EGFR) mutations. Each patient received closed drainage combined with simple negative pressure suction after thoracoscopic talc poudrage pleurodesis and oral Tarceva treatment. Short-term and long-term clinical therapeutic effects of Tarceva were evaluated. The EGFR mutation rate in pleural metastatic tissues of lung adenocarcinoma acquired through video-assisted thoracoscopic surgery was higher compared to that in surgical resection specimens, plasma specimens and pleural effusion specimens compared to previously reported results. There were significant statistical differences in the average extubation time (ppleural effusion (ppleural effusion 4 weeks after surgery (ppleural hypertrophy in the mutation group was significantly higher compared to the non-mutation group (ppleural hypertrophy was significantly reduced (ppleural effusion of lung adenocarcinoma with Tarceva therapy. Detection of EGFR mutations may determine the responsiveness of malignant pleural effusion to Tarceva treatment.

  3. EGFR Amplification and IDH Mutations in Glioblastoma Patients of the Northeast of Morocco

    Directory of Open Access Journals (Sweden)

    Nadia Senhaji

    2017-01-01

    Full Text Available Glioblastomas are the most frequent and aggressive primary brain tumors which are expressing various evolutions, aggressiveness, and prognosis. Thus, the 2007 World Health Organization classification based solely on the histological criteria is no longer sufficient. It should be complemented by molecular analysis for a true histomolecular classification. The new 2016 WHO classification of tumors of the central nervous system uses molecular parameters in addition to histology to reclassify these tumors and reduce the interobserver variability. The aim of this study is to determine the prevalence of IDH mutations and EGFR amplifications in the population of the northeast region of Morocco and then to compare the results with other studies. Methods. IDH1 codon 132 and IDH2 codon 172 were directly sequenced and the amplification of exon 20 of EGFR gene was investigated by qPCR in 65 glioblastoma tumors diagnosed at the University Hospital of Fez between 2010 and 2014. Results. The R132H IDH1 mutation was observed in 8 of 65 tumor samples (12.31%. No mutation of IDH2 was detected. EGFR amplification was identified in 17 cases (26.15%. Conclusion. A systematic search of both histological and molecular markers should be requisite for a good diagnosis and a better management of glioblastomas.

  4. Chronic pharmacologic inhibition of EGFR leads to cardiac dysfunction in C57BL/6J mice

    International Nuclear Information System (INIS)

    Barrick, Cordelia J.; Yu Ming; Chao, H.-H.; Threadgill, David W.

    2008-01-01

    Molecule-targeted therapies like those against the epidermal growth factor receptor (EGFR) are becoming widely used in the oncology clinic. With improvements in treatment efficacy, many cancers are being treated as chronic diseases, with patients having prolonged exposure to several therapies that were previously only given acutely. The consequence of chronic suppression of EGFR activity may lead to unexpected toxicities like altered cardiac physiology, a common organ site for adverse drug effects. To explore this possibility, we treated C57BL/6J (B6) mice with two EGFR small molecule tyrosine kinase inhibitors (TKIs), irreversible EKB-569 and reversible AG-1478, orally for 3 months. In B6 female mice, chronic exposure to both TKIs depressed body weight gain and caused significant changes in left ventricular (LV) wall thickness and cardiac function. No significant differences were observed in heart weight or cardiomyocyte size but histological analysis revealed an increase in fibrosis and in the numbers of TUNEL-positive cells in the hearts from treated female mice. Consistent with histological results, LV apoptotic gene expression was altered, with significant downregulation of the anti-apoptotic gene Bcl2l1. Although there were no significant differences in any of these endpoints in treated male mice, suggesting sex may influence susceptibility to TKI mediated toxicity, the LVs of treated male mice had significant upregulation of Egf, Erbb2 and Nppb over controls. Taken together, these data suggest that chronic dietary exposure to TKIs may result in pathological and physiological changes in the heart

  5. EGFR targeted therapy in non-small cell lung cancer: potential role of cetuximab

    Directory of Open Access Journals (Sweden)

    Chad A Reade

    2009-05-01

    Full Text Available Chad A Reade1, Apar Kishor Ganti1,21Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, USA; 2Section of Oncology-Hematology, Department of internal Medicine, VA Medical Center, Omaha, NE, USAAbstract: Chemotherapy alone has limited ability to significantly improve survival in non-small lung cancer (NSCLC beyond what has already been achieved. The epidermal growth factor (EGF pathway plays a vital role in the pathogenesis and progression of NSCLC. Two classes of drugs inhibit the EGF receptor (EGFR pathway: small molecules that inhibit the intracellular tyrosine kinase activity of the receptor, and monoclonal antibodies that target the extracellular domain in the ligand-binding region. Cetuximab is a human – mouse chimeric immunoglobulin G1 class monoclonal antibody directed against EGFR. Preclinical studies with cetuximab suggested that there was inhibition of growth of human NSCLC cell lines. Cetuximab is currently the focus of intense investigation in various patient populations with NSCLC. This review focuses on clinical trials of cetuximab in NSCLC and identifies future directions with this agent.Keywords: non-small cell lung cancer, EGFR, cetuximab, monoclonal antibodies

  6. Adenocarcinoma of the lung with EGFR gene mutation and subsequent resistance mechanisms exploration: case report

    Directory of Open Access Journals (Sweden)

    Xu L

    2017-09-01

    Full Text Available Li Xu,1,2 Qian Z Wang,1,2 Lin Wu1,2 1Department of the Second Chest Medicine, Hunan Cancer Hospital, Changsha, Hunan, People’s Republic of China; 2Department of the Second Chest Medicine, The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, People’s Republic of China Abstract: The treatment of lung cancer has made paradigm-shift advancements in the past decade with the development of therapies directed at specific genetic alterations, such as epidermal growth factor receptor (EGFR. Here, we present a rare case of lung adenocarcinoma harboring EGFR activating mutation and ALK overexpression. During the EGFR-tyrosine kinase inhibitors treatment, next-generation sequencing revealed phosphatidylinositol 3-kinase/Akt/mammalian target of rapamycin pathway amplifications in tumor specimen and subsequent T790M mutation via plasma circulating tumor DNA. In conclusion, this case illustrates the existence of concomitant resistance mechanisms and demonstrates that circulating tumor DNA can reflect tumor heterogeneity. Keywords: epidermal growth factor receptor, PI3K/Akt/mTOR pathway, T790M, next-generation sequencing, circulating tumor DNA

  7. Dynamic Bayesian Network Modeling of the Interplay between EGFR and Hedgehog Signaling.

    Science.gov (United States)

    Fröhlich, Holger; Bahamondez, Gloria; Götschel, Frank; Korf, Ulrike

    2015-01-01

    Aberrant activation of sonic Hegdehog (SHH) signaling has been found to disrupt cellular differentiation in many human cancers and to increase proliferation. The SHH pathway is known to cross-talk with EGFR dependent signaling. Recent studies experimentally addressed this interplay in Daoy cells, which are presumable a model system for medulloblastoma, a highly malignant brain tumor that predominately occurs in children. Currently ongoing are several clinical trials for different solid cancers, which are designed to validate the clinical benefits of targeting the SHH in combination with other pathways. This has motivated us to investigate interactions between EGFR and SHH dependent signaling in greater depth. To our knowledge, there is no mathematical model describing the interplay between EGFR and SHH dependent signaling in medulloblastoma so far. Here we come up with a fully probabilistic approach using Dynamic Bayesian Networks (DBNs). To build our model, we made use of literature based knowledge describing SHH and EGFR signaling and integrated gene expression (Illumina) and cellular location dependent time series protein expression data (Reverse Phase Protein Arrays). We validated our model by sub-sampling training data and making Bayesian predictions on the left out test data. Our predictions focusing on key transcription factors and p70S6K, showed a high level of concordance with experimental data. Furthermore, the stability of our model was tested by a parametric bootstrap approach. Stable network features were in agreement with published data. Altogether we believe that our model improved our understanding of the interplay between two highly oncogenic signaling pathways in Daoy cells. This may open new perspectives for the future therapy of Hedghog/EGF-dependent solid tumors.

  8. Inhibition of GRP78 abrogates radioresistance in oropharyngeal carcinoma cells after EGFR inhibition by cetuximab.

    Directory of Open Access Journals (Sweden)

    Chaonan Sun

    Full Text Available The EGFR-specific mAb cetuximab is one of the most effective treatments for oropharyngeal carcinoma, while patient responses to EGFR inhibitors given alone are modest. Combination treatment with radiation can improve the efficacy of treatment through increasing radiosensitivity, while resistance to radiation after administration of cetuximab limits its efficiency. Radiation and drugs can damage the endoplasmic reticulum (ER homeostatic state and result in ER stress (ERS, subsequently causing resistance to radiation and drugs. Whether the ERS pathway is involved in radioresistance after administration of cetuximab has not been reported. Herein, we show that cetuximab could increase the radiosensitivity of FaDu cells but not Detroit562 cells. In addition, cetuximab inhibited the radiation-induced activation of the ERS signalling pathway IRE1α/ATF6-GRP78 in FaDu cells, while this effect was absent in Detroit562 cells. Silencing GRP78 increased the radiosensitivity of oropharyngeal carcinoma cells and inhibited radiation-induced DNA double-strand-break (DSB repair and autophagy. More interestingly, silencing GRP78 abrogated resistance to cetuximab and radiation in Detroit562 cells and had a synergistic effect with cetuximab in increasing the radiosensitivity of FaDu cells. Immunohistochemistry showed that overexpression of both GRP78 and EGFR was associated with a poor prognosis in oropharyngeal carcinoma patients (P<0.05. Overall, the results of this study show that radioresistance after EGFR inhibition by cetuximab is mediated by the ERS signalling pathway IRE1α/ATF6-GRP78. This suppression was consequently unable to inhibit radiation-induced DSB repair and autophagy in oropharyngeal carcinoma cells, which conferred resistance to radiotherapy and cetuximab. These results suggest that the cooperative effects of radiotherapy and cetuximab could be further improved by inhibiting GRP78 in non-responsive oropharyngeal carcinoma patients.

  9. Cellular Response to Titanium Dioxide Nanoparticles in Intestinal Epithelial Caco-2 Cells is Dependent on Endocytosis-Associated Structures and Mediated by EGFR

    Science.gov (United States)

    Krüger, Kristin; Schrader, Katrin; Klempt, Martin

    2017-01-01

    Titanium dioxide (TiO2) is one of the most applied nanomaterials and widely used in food and non-food industries as an additive or coating material (E171). It has been shown that E171 contains up to 37% particles which are smaller than 100 nm and that TiO2 nanoparticles (NPs) induce cytotoxicity and inflammation. Using a nuclear factor Kappa-light-chain enhancer of activated B cells (NF-κB) reporter cell line (Caco-2nfkb-RE), Real time polymerase chain reaction (PCR), and inhibition of dynamin and clathrin, it was shown that cellular responses induced by 5 nm and 10 nm TiO2 NPs (nominal size) depends on endocytic processes. As endocytosis is often dependent on the epithelial growth factor receptor (EGFR), further investigations focused on the involvement of EGFR in the uptake of TiO2 NPs: (1) inhibition of EGFR reduced inflammatory markers of the cell (i.e., nuclear factor (NF)-κB activity, mRNA of IL8, CCL20, and CXCL10); and (2) exposure of Caco-2 cells to TiO2 NPs activated the intracellular EGFR cascade beginning with EGFR-mediated extracellular signal-regulated kinases (ERK)1/2, and including transcription factor ELK1. This was followed by the expression of ERK1/2 target genes CCL2 and CXCL3. We concluded that TiO2 NPs enter the cell via EGFR-associated endocytosis, followed by activation of the EGFR/ERK/ELK signaling pathway, which finally induces NF-κB. No changes in inflammatory response are observed in Caco-2 cells exposed to 32 nm and 490 nm TiO2 particles. PMID:28387727

  10. Cellular Response to Titanium Dioxide Nanoparticles in Intestinal Epithelial Caco-2 Cells is Dependent on Endocytosis-Associated Structures and Mediated by EGFR.

    Science.gov (United States)

    Krüger, Kristin; Schrader, Katrin; Klempt, Martin

    2017-04-07

    Titanium dioxide (TiO₂) is one of the most applied nanomaterials and widely used in food and non-food industries as an additive or coating material (E171). It has been shown that E171 contains up to 37% particles which are smaller than 100 nm and that TiO₂ nanoparticles (NPs) induce cytotoxicity and inflammation. Using a nuclear factor Kappa-light-chain enhancer of activated B cells (NF-κB) reporter cell line (Caco-2 nfkb-RE ), Real time polymerase chain reaction (PCR), and inhibition of dynamin and clathrin, it was shown that cellular responses induced by 5 nm and 10 nm TiO₂ NPs (nominal size) depends on endocytic processes. As endocytosis is often dependent on the epithelial growth factor receptor (EGFR), further investigations focused on the involvement of EGFR in the uptake of TiO₂ NPs: (1) inhibition of EGFR reduced inflammatory markers of the cell (i.e., nuclear factor (NF)-κB activity, mRNA of IL8, CCL20, and CXCL10); and (2) exposure of Caco-2 cells to TiO₂ NPs activated the intracellular EGFR cascade beginning with EGFR-mediated extracellular signal-regulated kinases (ERK)1/2, and including transcription factor ELK1. This was followed by the expression of ERK1/2 target genes CCL2 and CXCL3. We concluded that TiO₂ NPs enter the cell via EGFR-associated endocytosis, followed by activation of the EGFR/ERK/ELK signaling pathway, which finally induces NF-κB. No changes in inflammatory response are observed in Caco-2 cells exposed to 32 nm and 490 nm TiO₂ particles.

  11. P2Y2 Receptor and EGFR Cooperate to Promote Prostate Cancer Cell Invasion via ERK1/2 Pathway.

    Science.gov (United States)

    Li, Wei-Hua; Qiu, Ying; Zhang, Hong-Quan; Tian, Xin-Xia; Fang, Wei-Gang

    2015-01-01

    As one member of G protein-coupled P2Y receptors, P2Y2 receptor can be equally activated by extracellular ATP and UTP. Our previous studies have proved that activation of P2Y2 receptor by extracellular ATP could promote prostate cancer cell invasion and metastasis in vitro and in vivo via regulating the expressions of some epithelial-mesenchymal transition/invasion-related genes (including IL-8, E-cadherin, Snail and Claudin-1), and the most significant change in expression of IL-8 was observed after P2Y2 receptor activation. However, the signaling pathway downstream of P2Y2 receptor and the role of IL-8 in P2Y2-mediated prostate cancer cell invasion remain unclear. Here, we found that extracellular ATP/UTP induced activation of EGFR and ERK1/2. After knockdown of P2Y2 receptor, the ATP -stimulated phosphorylation of EGFR and ERK1/2 was significantly suppressed. Further experiments showed that inactivation of EGFR and ERK1/2 attenuated ATP-induced invasion and migration, and suppressed ATP-mediated IL-8 production. In addition, knockdown of IL-8 inhibited ATP-mediated invasion and migration of prostate cancer cells. These findings suggest that P2Y2 receptor and EGFR cooperate to upregulate IL-8 production via ERK1/2 pathway, thereby promoting prostate cancer cell invasion and migration. Thus blocking of the P2Y2-EGFR-ERK1/2 pathway may provide effective therapeutic interventions for prostate cancer.

  12. Colon-specific delivery of a probiotic-derived soluble protein ameliorates intestinal inflammation in mice through an EGFR-dependent mechanism

    Science.gov (United States)

    Yan, Fang; Cao, Hanwei; Cover, Timothy L.; Washington, M. Kay; Shi, Yan; Liu, LinShu; Chaturvedi, Rupesh; Peek, Richard M.; Wilson, Keith T.; Polk, D. Brent

    2011-01-01

    Probiotic bacteria can potentially have beneficial effects on the clinical course of several intestinal disorders, but our understanding of probiotic action is limited. We have identified a probiotic bacteria–derived soluble protein, p40, from Lactobacillus rhamnosus GG (LGG), which prevents cytokine-induced apoptosis in intestinal epithelial cells. In the current study, we analyzed the mechanisms by which p40 regulates cellular responses in intestinal epithelial cells and p40’s effects on experimental colitis using mouse models. We show that the recombinant p40 protein activated EGFR, leading to Akt activation. Activation of EGFR by p40 was required for inhibition of cytokine-induced apoptosis in intestinal epithelial cells in vitro and ex vivo. Furthermore, we developed a pectin/zein hydrogel bead system to specifically deliver p40 to the mouse colon, which activated EGFR in colon epithelial cells. Administration of p40-containing beads reduced intestinal epithelial apoptosis and disruption of barrier function in the colon epithelium in an EGFR-dependent manner, thereby preventing and treating DSS-induced intestinal injury and acute colitis. Furthermore, p40 activation of EGFR was required for ameliorating colon epithelial cell apoptosis and chronic inflammation in oxazolone-induced colitis. These data define what we believe to be a previously unrecognized mechanism of probiotic-derived soluble proteins in protecting the intestine from injury and inflammation. PMID:21606592

  13. Rapid optical determination of β-lactamase and antibiotic activity

    Science.gov (United States)

    2014-01-01

    Background The absence of rapid tests evaluating antibiotic susceptibility results in the empirical prescription of antibiotics. This can lead to treatment failures due to escalating antibiotic resistance, and also furthers the emergence of drug-resistant bacteria. This study reports a rapid optical method to detect β-lactamase and thereby assess activity of β-lactam antibiotics, which could provide an approach for targeted prescription of antibiotics. The methodology is centred on a fluorescence quenching based probe (β-LEAF – β-Lactamase Enzyme Activated Fluorophore) that mimics the structure of β-lactam antibiotics. Results The β-LEAF assay was performed for rapid determination of β-lactamase production and activity of β-lactam antibiotic (cefazolin) on a panel of Staphylococcus aureus ATCC strains and clinical isolates. Four of the clinical isolates were determined to be lactamase producers, with the capacity to inactivate cefazolin, out of the twenty-five isolates tested. These results were compared against gold standard methods, nitrocefin disk test for β-lactamase detection and disk diffusion for antibiotic susceptibility, showing results to be largely consistent. Furthermore, in the sub-set of β-lactamase producers, it was demonstrated and validated that multiple antibiotics (cefazolin, cefoxitin, cefepime) could be assessed simultaneously to predict the antibiotic that would be most active for a given bacterial isolate. Conclusions The study establishes the rapid β-LEAF assay for β-lactamase detection and prediction of antibiotic activity using S. aureus clinical isolates. Although the focus in the current study is β-lactamase-based resistance, the overall approach represents a broad diagnostic platform. In the long-term, these studies form the basis for the development of assays utilizing a broader variety of targets, pathogens and drugs. PMID:24708478

  14. Determination of root activity pattern in citrus under irrigation (Tumbaco)

    International Nuclear Information System (INIS)

    Aizaga, Jorge; Calvache, Marcelo

    1992-01-01

    This experiment was carried out in Tumbaco, province of Pichincha, from january to april 1991. The objective of the study was to determine the root activity patterns in citrus. Tangerine plants of two varieties(common and willowleaf on rugged lemon pattern) three years old were used. A solution of Na H 2 PO 4 labeled with 3 2 P was applied at four distances: 0.30, 0.60, 0.90 and 1.20 m, distributed in a circle around the trees. Leaf samples were taken at 20,37 and 64 days after application and 3 2 P activity was determined. Statistical analysis of the data showed a highly significant variation between treatments and two ranges of significance were defined: the first one included the treatments at 0.30 and 0.60 m, and the second, the treatments at 0.90 and 1.20 m. At the same time soil moisture data were collected. These data demonstrated the relation between soil moisture and root activity and efficiency. With the obtained information it can be concluded that in trees over three years old, and in Tumbaco conditions of citrus management and ecology, the best distance to apply fertilizer is in circles located at 0.30 to 0.60 . from the trunck of tree

  15. Determination of impurities in beryl by neutron activation analysis

    International Nuclear Information System (INIS)

    Swain, K.K.; Dalvi, Aditi A.; Ajith, Nicy

    2015-01-01

    Beryl is a chemically complex and highly compositionally variable gem-forming mineral found in a variety of locations worldwide. Pure beryl is colorless, but the presence of impurities imparts colors such as green, blue, yellow, red, and white. It is one of the most important gem minerals and the gems are named by their color. The impurities in beryl can be determined using various analytical techniques. Neutron activation analysis (NAA) is a sensitive technique for multielement analysis of geological samples. Four beryl samples, collected from Nayakund Mehandi Block, Parseoni, Maharashtra, were received from Geological Survey of India (GSI), Pune. Powdered samples (50-100 mg) along with comparators (IAEA Soil-7) were packed in aluminum foils, sealed in an aluminum container and irradiated for 7 days in tray rod facility of Dhruva reactor, BARC, Mumbai. After irradiation, samples were brought to laboratory. Samples were opened, transferred into polyethylene packets and weighed. Gamma activity measurements were carried out using 45% HPGe detector coupled to 8 k multi channel analyzer. For the determination of manganese, which produces relatively shorter lived activation product ( 56 Mn: T 1/2 = 2.56 h), samples were sealed in polyethylene pouches and irradiated in graphite reflector position of Critical facility reactor, BARC, Mumbai. Relative method of NAA was used for concentration calculations. IAEA reference material (RM), SL -1 (lake sediment) was analyzed for quality control. Percentage errors on the measured concentrations of the elements are within ± 8% with respect to the recommended/information values

  16. Method to determine the activity concentration and total activity of radioactive waste

    International Nuclear Information System (INIS)

    Angeles C, A.

    2001-02-01

    A characteristic system of radioactive waste is described to determine the concentration of radionuclides activity and the total activity of bundles of radioactive waste. The system this integrated by three subsystems: - Elevator of drums. - Electromechanics. - Gamma spectroscopy. In the system it is analyzed waste of issuing gamma specifically, and this designed for materials of relative low density and it analyzes materials of cylindrical recipients

  17. The activation method for determining neutron spectra and fluences

    International Nuclear Information System (INIS)

    Hogel, J.; Vespalec, R.

    1980-01-01

    3 mm thick foils of 4 and 17 mm in diameter were used for measurements. NaI scintillation detectors 45 mm in diameter by 50 mm thick and 40 mm in diameter by 1 mm thick, and a Ge-Li spectrometer of 53 cm 3 in volume were used for gamma detection. A photopeak or a certain part of the integral spectrum was measured for each radionuclide. Computer code PIKAR was applied in automatic calculation of a simple gamma spectrum obtained using the semiconductor spectrometer. The FACT code was used for calculating foil activity. Codes SAND II and RFSP were used for neutron spectra unfolding. Ge-Li detector spectrometry was used for determining neutron fluence. Code FLUE was used for determining the mean value of neutron flux density and fluence. (J.P.)

  18. Neutron activation analysis on determination of arsenic in biological matrixes

    Energy Technology Data Exchange (ETDEWEB)

    Menezes, Maria Angela de B.C.; Silva, Maria Aparecida, E-mail: menezes@cdtn.br, E-mail: cida@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    Aiming at giving support to the Worker's Health Awareness Program of the Municipal Department of Health of Belo Horizonte, an assessment related arsenic was carried out in two galvanising factories by means of hair and toenail samples analysis as biomonitors. The arsenic was determined in all matrixes from the factories where gold electrodeposition process was applied. This is because arsenic salts are usually added to gold bath to improve the metal covering. The high concentration results surprised the health surveillance professionals, and alerted for the need of assessing the influence of a long-term exposure. Studies concerning galvanising process have usually been developed broaching many aspects, but so far few works has pointed out the detection and measurement of other elements like arsenic. The k{sub 0}-Instrumental Neutron Activation method was applied confirming to be a suitable technique on determination of arsenic in biological matrixes. (author)

  19. Proton-activation technique for the determination of antimony

    International Nuclear Information System (INIS)

    Krivan, V.; Barth, P.

    1979-01-01

    Photon-activation analysis has been applied to the determination of antimony. Thick-target yields and analytical sensitivities are given for the indicator-radionuclides sup(119m)Te, sup(119g)Te, sup(121m)Te, sup(121g)Te, sup(123m)Te, sup(120m)Sb and sup(122g)Sb for proton energies between 9 and 25 MeV. In irradiations with a 5-μA beam for 5 hr, followed by a specific separation of the indicator-radionuclides, limits of detection at the ppm level can be achieved. Data are given for the most significant interfering reactions. Antimony was determined instrumentally in bismuth of very pure grade and the results are compared with those obtained from two independent techniques. (author)

  20. Neutron activation analysis on determination of arsenic in biological matrixes

    International Nuclear Information System (INIS)

    Menezes, Maria Angela de B.C.; Silva, Maria Aparecida

    2013-01-01

    Aiming at giving support to the Worker's Health Awareness Program of the Municipal Department of Health of Belo Horizonte, an assessment related arsenic was carried out in two galvanising factories by means of hair and toenail samples analysis as biomonitors. The arsenic was determined in all matrixes from the factories where gold electrodeposition process was applied. This is because arsenic salts are usually added to gold bath to improve the metal covering. The high concentration results surprised the health surveillance professionals, and alerted for the need of assessing the influence of a long-term exposure. Studies concerning galvanising process have usually been developed broaching many aspects, but so far few works has pointed out the detection and measurement of other elements like arsenic. The k 0 -Instrumental Neutron Activation method was applied confirming to be a suitable technique on determination of arsenic in biological matrixes. (author)

  1. Precise determination of aluminium by instrumental neutron activation

    Energy Technology Data Exchange (ETDEWEB)

    Fleming, R F; Lindstrom, R M

    1987-06-01

    Because of the short half-life of /sup 28/Al, the determination of aluminium by neutron activation is subject to many inaccuracies. These errors can all be made smaller by counting statistics. The transfer function from the observed number of net counts to the counting rate at the end of irradiation is modeled as a product of three processes: radioactive decay and extending and nonextending dead time. The procedure was applied to the analysis of NBS SRM 1633a Fly Ash. The mean concentration measured was 14.085% Al, with a standard deviation of the mean 0.023% Al for four determinations. The final results showed no significant imprecision beyond counting statistics. The accuracy of the method is shown by the analysis of high-purity single-crystal sapphire

  2. Determination of inorganic component in plastics by neutron activation analysis

    International Nuclear Information System (INIS)

    Mateus, Sandra Fonseca; Saiki, Mitiko

    1995-01-01

    In order to identify possible sources of heavy metals in municipal solid waste incinerator ashes, plastic materials originated mainly from household waste were analyzed by using instrumental neutron activation analysis method. Plastic samples and synthetic standards of elements were irradiated at the IEA-R1 nuclear reactor for 8 h under thermal neutron flux of about 10 13 n cm -2 s -1 . After adequate decay time, counting were carried out using a hyperpure Ge detector and the concentrations of the elements As, Ba, Br, Cd, Co, Cr, Fe, Sb, Sc, Se, Sn, Ti and Zn were determined. For some samples, not all these elements were detected. Besides, the range of concentrations determined in similar type and colored samples varied from a few ppb to percentage. In general, colored and opaque plastic samples presented higher concentrations of the elements than those obtained from transparent and milky plastics. Precision of the results was also evaluated. (author). 3 refs., 2 tabs

  3. Determination of gallium in flint clay by neutron activation analysis

    International Nuclear Information System (INIS)

    Padova, A.; Even, O.

    1975-01-01

    Neutron activation analysis was applied to determine gallium traces in different flint clay samples found in Israel. The principal 835 KeV gamma ray of gallium-72 was measured with a 60 cm 2 Ge(Li) spectrometer in conjunction with a Packard 4000 channel analyzer and Wang table computer, model 720 C. Samples were weighed into polyethylene vials, sealed and inserted into polyethylene rabbit. Gallium metal and gallium oxide used as standards were similarly prepared for irradiation for 10 minutes in the I.R.R.I., at a thermal flux of 3.5x10 12 n/cm 2 sec. Careful calibration of the spectrometer and judicious choice of cooling time eliminate the influence of such elements as europium-152, and sodium-24 and make possible the determination of gallium without prior chemical separation. Representative Israel flint clay samples contain about 55 ppm gallium. (B.G.)

  4. Cetuximab insufficiently inhibits glioma cell growth due to persistent EGFR downstream signaling

    DEFF Research Database (Denmark)

    Hasselbalch, Benedikte; Lassen, Ulrik; Poulsen, Hans S

    2010-01-01

    Overexpression and/or amplification of the epidermal growth factor receptor (EGFR) is present in 35-45% of primary glioblastoma multiforme tumors and has been correlated with a poor prognosis. In this study, we investigated the effect of cetuximab and intracellular signaling pathways downstream...... of EGFR, important for cell survival and proliferation. We show insufficient EGFR downregulation and competition with endogenous EGFR ligands upon cetuximab treatment. Dose-response experiments showed inhibition of EGFR phosphorylation without affecting two of the prominent downstream signaling pathways....... Our results indicate that amplification and/or overexpression of EGFR is an unsatisfactory predictor for response to cetuximab....

  5. Combined EGFR and VEGFR versus single EGFR signaling pathways inhibition therapy for NSCLC: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Xinji Zhang

    Full Text Available BACKGROUND: Lung cancer is a heterogeneous disease with multiple signaling pathways influencing tumor cell survival and proliferation, and it is likely that blocking only one of these pathways allows others to act as salvage or escape mechanisms for cancer cells. Whether combined inhibition therapy has greater anti-tumor activity than single inhibition therapy is a matter of debate. Hence, a meta-analysis comparing therapy inhibiting both VEGFR and EGFR signaling pathways with that inhibiting EGFR signaling pathway alone was performed. METHODOLOGY AND PRINCIPAL FINDINGS: We searched PubMed, EMBASE database and the proceedings of major conferences for relevant clinical trials. Outcomes analyzed were objective tumor response rate (ORR, progression-free survival (PFS, overall survival (OS and toxicity. Besides, subgroup analyses were performed to investigate whether the combined inhibition therapy is best performed using combination of selective agents or a single agent with multiple targets. Six trials recruiting 3,302 patients were included in the analysis. Combined inhibition therapy was associated with a 3% improvement in OS as compared with single-targeted therapy, but this difference was not statistically significant (HR, 0.97; 95% CI, 0.89-1.05; P=0.472. Patients receiving combined inhibition therapy had significant longer PFS than the group with single-targeted therapy (HR, 0.80; 95% CI, 0.67-0.95; P=0.011. There was no difference in the ORR between the groups (OR, 1.44; 95% CI, 0.95-2.18; P=0.085. Subgroup analysis revealed that combined inhibition therapy using combination regimens was associated with statistically significant improvement in both ORR and PFS. Toxicity was greater in combined inhibition therapy. CONCLUSIONS: There is no evidence to support the use of combined inhibition therapy in unselected patients with advanced NSCLC. However, given the significant advantage in ORR and PFS, combined inhibition therapy using combination

  6. Determination of ancient ceramics reference material by neutron activation analysis

    International Nuclear Information System (INIS)

    Li Huhou; Sun Jingxin; Wang Yuqi; Lu Liangcai

    1986-01-01

    Contents of trace elements in the reference material of ancient ceramics (KPS-1) were determined by means of activation analysis, using thermal neutron irradiation produced in nuclear reactor. KPS-1 favoured the analysis of ancient ceramics because it had not only many kinds of element but also appropriate contents of composition. The values presented here are reliable within the experimental precision, and have shown that the reference material had a good homogeneity. So KPS-1 can be used as a suitable reference material for the ancient ceramics analysis

  7. Radon determination by activated charcoal adsorption and liquid scintillation measurement

    International Nuclear Information System (INIS)

    Lopez, F.O.; Canoba, A.C.

    1998-01-01

    A passive diffusion method for the determination of radon concentration has been optimised and calibrated. The device consists of a scintillation vial containing activated charcoal, a diffusion barrier and a desiccant agent. The response to diverse atmospheric humidity and variable exposure intervals was studied. The result is a detector, which is independent of atmospheric humidity for at least (up to) 7 days of exposure. The method was compared with electret detectors (US EPA) with very satisfactory results. The advantages of this method are its simplicity, low cost, low detection limit, the total automatization of the measurement and its total independence of humidity to measure in a wide range of radon concentrations. (author) [es

  8. Determination of thorium concentration in seawater by neutron activation analysis

    International Nuclear Information System (INIS)

    Huh, C.A.; Bacon, M.P.

    1985-01-01

    A sensitive neutron activation analysis method has been successfully developed to determine 232 Th concentration in seawater. The method involves both preirradiation and postirradiation radiochemical separations. The isotopes were separated from the samples and purified during the preirradiation chemistry. 233 Pa was extracted and counted after the irradiation. Yields were monitored with 230 Th and 231 Pa tracers. The separation and purification schemes include ion exchange chromatography and solvent extraction. By this method the authors have measured 232 Th concentrations in some seawater samples that are 1 order of magnitude lower than most previously reported values. 21 references, 3 figures, 2 tables

  9. Determination of phosphorus in silicate rocks by activation analysis

    International Nuclear Information System (INIS)

    Khalil, S.O.

    1974-01-01

    A neutron activation method for the determination of phosphorus from ammonium phosphomolibdate precipitate is applied to silicate rocks. Ammonium phosphate is added as carrier to the irradiated rock powder and the phosphorus is recovered as ammonium phosphomolibdate, which is precipitated several times in the presence of appropriate holdback carriers to ensure its radiochemical purity and then finally dissolved and reprecipitated as AgTlPO 4 for weighing and counting. The samples were irradiated for 3 1/2 days in a thermal flux of 2.10 10 n.s -1 .cm -2 and the β-activities were measured by an end-window Geiger-Mueller counter. The results for rock standards granite G-1 and diabase W-1 are given. (K.A.)

  10. EGF stimulates the activation of EGF receptors and the selective activation of major signaling pathways during mitosis.

    Science.gov (United States)

    Wee, Ping; Shi, Huaiping; Jiang, Jennifer; Wang, Yuluan; Wang, Zhixiang

    2015-03-01

    Mitosis and epidermal growth factor (EGF) receptor (EGFR) are both targets for cancer therapy. The role of EGFR signaling in mitosis has been rarely studied and poorly understood. The limited studies indicate that the activation of EGFR and downstream signaling pathways is mostly inhibited during mitosis. However, we recently showed that EGFR is phosphorylated in response to EGF stimulation in mitosis. Here we studied EGF-induced EGFR activation and the activation of major signaling pathways downstream of EGFR during mitosis. We showed that EGFR was strongly activated by EGF during mitosis as all the five major tyrosine residues including Y992, Y1045, Y1068, Y1086, and Y1173 were phosphorylated to a level similar to that in the interphase. We further showed that the activated EGFR is able to selectively activate some downstream signaling pathways while avoiding others. Activated EGFR is able to activate PI3K and AKT2, but not AKT1, which may be responsible for the observed effects of EGF against nocodazole-induced cell death. Activated EGFR is also able to activate c-Src, c-Cbl and PLC-γ1 during mitosis. However, activated EGFR is unable to activate ERK1/2 and their downstream substrates RSK and Elk-1. While it activated Ras, EGFR failed to fully activate Raf-1 in mitosis due to the lack of phosphorylation at Y341 and the lack of dephosphorylation at pS259. We conclude that contrary to the dogma, EGFR is activated by EGF during mitosis. Moreover, EGFR-mediated cell signaling is regulated differently from the interphase to specifically serve the needs of the cell in mitosis. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. The determination of chromium in water samples by neutron activation analysis after preconcentration on activated carbon

    International Nuclear Information System (INIS)

    Sloot, H.A. van der

    1977-01-01

    A method is presented for the determination of chromium in sea- and fresh water. Chromium is concentrated on activated carbon from a neutral solution after a previous reduction of chromate with sodium sulfite at pH 1.5. The adsorption conditions, acidity, concentrations, amount of carbon, stirring-time, sample-volume, salinity, the influence of storage on the ratio of tervalent to hexavalent chromium, were investigated. The final determination of the total chromium content is performed by instrumental neutron-activation analysis. By preconcentration on activated carbon, a differentiation between tervalent and hexavalent chromium is possible. A separate determination of both species is not yet feasible due to the high carbon blank and to the necessity of measuring the adsorption percentage on carbon. The lower limit of determination, which depends on the value of the carbon blank, is 0.05 μg Cr/l with a precision of 20%. The determination is hampered by the considerable blank from the carbon. The use of activated carbon prepared from recrystallized sugar will probably improve the lower limit of determination and possibly allow the determination of chromate. (T.G.)

  12. Determination of chromium in water samples by neutron activation analysis after preconcentration on activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    van der Sloot, H A [Stichting Reactor Centrum Nederland, Petten

    1977-01-01

    A method is presented for the determination of chromium in sea- and fresh water. Chromium is concentrated on activated carbon from a neutral solution after a previous reduction of chromate with sodium sulfite at pH 1.5. The adsorption conditions, acidity, concentrations, amount of carbon, stirring-time, sample-volume, salinity, the influence of storage on the ratio of tervalent to hexavalent chromium, were investigated. The final determination of the total chromium content is performed by instrumental neutron-activation analysis. By preconcentration on activated carbon, a differentiation between tervalent and hexavalent chromium is possible. A separate determination of both species is not yet feasible due to the high carbon blank and to the necessity of measuring the adsorption percentage on carbon. The lower limit of determination, which depends on the value of the carbon blank, is 0.05 ..mu..g Cr/l with a precision of 20%. The determination is hampered by the considerable blank from the carbon. The use of activated carbon prepared from recrystallized sugar will probably improve the lower limit of determination and possibly allow the determination of chromate.

  13. Propolin C Inhibited Migration and Invasion via Suppression of EGFR-Mediated Epithelial-to-Mesenchymal Transition in Human Lung Cancer Cells

    Directory of Open Access Journals (Sweden)

    Jih-Tung Pai

    2018-01-01

    Full Text Available Controlling lung cancer cell migration and invasion via epithelial-to-mesenchymal transition (EMT through the regulation of epidermal growth factor receptor (EGFR signaling pathway has been demonstrated. Searching biological active phytochemicals to repress EGFR-regulated EMT might prevent lung cancer progression. Propolis has been used as folk medicine in many countries and possesses anti-inflammatory, antioxidant, and anticancer activities. In this study, the antimigration and anti-invasion activities of propolin C, a c-prenylflavanone from Taiwanese propolis, were investigated on EGFR-regulated EMT signaling pathway. Cell migration and invasion activities were dose-dependently suppressed by noncytotoxic concentration of propolin C. Downregulations of vimentin and snail as well as upregulation of E-cadherin expressions were through the inhibition of EGFR-mediated phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt and extracellular signal-regulated kinase (ERK signaling pathway in propolin C-treated cells. In addition, EGF-induced migration and invasion were suppressed by propolin C-treated A549 lung cancer cells. No significant differences in E-cadherin expression were observed in EGF-stimulated cells. Interestingly, EGF-induced expressions of vimentin, snail, and slug were suppressed through the inhibition of PI3K/Akt and ERK signaling pathway in propolin C-treated cells. Inhibition of cell migration and invasion by propolin C was through the inhibition of EGF/EGFR-mediated signaling pathway, followed by EMT suppression in lung cancer.

  14. Intracranial Pressure Is a Determinant of Sympathetic Activity

    Directory of Open Access Journals (Sweden)

    Eric A. Schmidt

    2018-02-01

    Full Text Available Intracranial pressure (ICP is the pressure within the cranium. ICP rise compresses brain vessels and reduces cerebral blood delivery. Massive ICP rise leads to cerebral ischemia, but it is also known to produce hypertension, bradycardia and respiratory irregularities due to a sympatho-adrenal mechanism termed Cushing response. One still unresolved question is whether the Cushing response is a non-synaptic acute brainstem ischemic mechanism or part of a larger physiological reflex for arterial blood pressure control and homeostasis regulation. We hypothesize that changes in ICP modulates sympathetic activity. Thus, modest ICP increase and decrease were achieved in mice and patients with respectively intra-ventricular and lumbar fluid infusion. Sympathetic activity was gauged directly by microneurography, recording renal sympathetic nerve activity in mice and muscle sympathetic nerve activity in patients, and gauged indirectly in both species by heart-rate variability analysis. In mice (n = 15, renal sympathetic activity increased from 29.9 ± 4.0 bursts.s−1 (baseline ICP 6.6 ± 0.7 mmHg to 45.7 ± 6.4 bursts.s−1 (plateau ICP 38.6 ± 1.0 mmHg and decreased to 34.8 ± 5.6 bursts.s−1 (post-infusion ICP 9.1 ± 0.8 mmHg. In patients (n = 10, muscle sympathetic activity increased from 51.2 ± 2.5 bursts.min−1 (baseline ICP 8.3 ± 1.0 mmHg to 66.7 ± 2.9 bursts.min−1 (plateau ICP 25 ± 0.3 mmHg and decreased to 58.8 ± 2.6 bursts.min−1 (post-infusion ICP 14.8 ± 0.9 mmHg. In patients 7 mmHg ICP rise significantly increases sympathetic activity by 17%. Heart-rate variability analysis demonstrated a significant vagal withdrawal during the ICP rise, in accordance with the microneurography findings. Mice and human results are alike. We demonstrate in animal and human that ICP is a reversible determinant of efferent sympathetic outflow, even at relatively low ICP levels. ICP is a biophysical stress related to the forces within the brain. But ICP

  15. Co-expression of periostin and EGFR in patients with esophageal squamous cell carcinoma and their prognostic significance

    Directory of Open Access Journals (Sweden)

    Jia W

    2016-08-01

    Full Text Available Wei Jia,1 Wei Wang,1 Chu-shu Ji,1 Jun-yang Niu,2 Ya-jing Lv,1 Hang-cheng Zhou,2 Bing Hu1 1Department of Medical Oncology, 2Department of Pathology, Anhui Provincial Hospital, Anhui Medical University, Hefei, People’s Republic of China Background: Both periostin (PN and epidermal growth factor receptor (EGFR can predict the prognosis of several carcinomas alone. However, coexpression of PN and EGFR in esophageal squamous cell carcinoma (ESCC still remains unknown. We aimed to clarify their relationship with clinicopathological factors and prognostic significance of their coexpression in ESCC. Patients and methods: In this single-center retrospective study, immunohistochemistry was performed to evaluate the expression of PN and EGFR in ESCC and paracarcinomatous tissues of 83 patients. The quantitative expression levels of PN and EGFR were examined in two ESCC and tumor-adjacent tissues. The levels of PN and EGFR expression were correlated with clinicopathological parameters by the χ2 or Kruskal–Wallis method. Spearman’s rank correlation test was performed to determine the relationship between PN and EGFR expression levels. Kaplan–Meier and Cox regression analyses were used to detect the prognostic factors of disease-free survival (DFS and overall survival (OS. Results: The high expression of PN protein in ESCC tissues was significantly associated with tumor length (P=0.044, differentiation grade (P=0.003, venous invasion (P=0.010, invasion depth (P=0.007, lymphatic metastasis (P=0.000, and tumor stage (P=0.000. The high expression of EGFR protein in ESCC tissues was only significantly related to lymphatic metastasis (P=0.000, invasion depth (P=0.022, and tumor stage (P=0.000. Kaplan–Meier analysis showed that high expression of PN was closely correlated to reduced OS (P=0.000 and DFS (P=0.000, which was consistent with EGFR expression. Cox regression analysis identified PN and EGFR as independent poor prognostic factors of OS and DFS

  16. EGFR and KRAS quality assurance schemes in pathology : generating normative data for molecular predictive marker analysis in targeted therapy

    NARCIS (Netherlands)

    Thunnissen, Erik; Bovée, Judith V M G; Bruinsma, Hans; van den Brule, Adriaan J C; Dinjens, Winand; Heideman, Daniëlle A M; Meulemans, Els; Nederlof, Petra; van Noesel, Carel; Prinsen, Clemens F M; Scheidel, Karen; van de Ven, Peter M; de Weger, Roel; Schuuring, Ed; Ligtenberg, Marjolijn

    2011-01-01

    Introduction The aim of this study was to compare the reproducibility of epidermal growth factor receptor (EGFR) immunohistochemistry (IHC), EGFR gene amplification analysis, and EGFR and KRAS mutation analysis among different laboratories performing routine diagnostic analyses in pathology in The

  17. Determination of mutually interfering elements in activation analysis

    International Nuclear Information System (INIS)

    Figueiredo, A.M.G.

    1979-01-01

    The determination of the elements present in the groups scandium-zinc, mercury-selenium and arsenic-antimony-bromine represents a classical problem in thermal neutron activation analysis because the gamma-ray peaks of the radioisotopes produced from these elements by activation appear very close in the spectrum. A study is made of the possibility of simultaneous instrumental determination of these elements by means of the spectrum stripping technique, using a 400-channel analyser coupled to a Nal(Tl) detector and a 4096-channel analyser coupled to a Ge(Li) detector. Artificial mixtures of the interfering elements in varying proportions are prepared, so as to reproduce possible real samples, where the elements may be present at several concentrations. Radiochemical separation techniques for the cited elements are studied with the use of tracers. For the separation of scadium and zinc, the technique of extraction chromatography is applied. The separation of mercury and selenium is accomplished by means of ion exchange. The technique of coprecipitation is used to separate bromine from arsenic and antimony followed by ion exchange to isolate these two elements from each other. The precision and the accuracy of the results are discussed. (Author) [pt

  18. Uranium in coral skeletons determined by epithermal neutron activation analysis

    International Nuclear Information System (INIS)

    Ohde, S.; Hossain, M.M.M.; Ozaki, H.; Masuzawa, T.

    2003-01-01

    A simple and non-destructive method has been proposed for the routine determination of uranium by epithermal neutron activation analysis in coral skeletons. Using a cadmium capsule, about 0.1-0.2 g samples were irradiated for 6 hours in the Triga Mark II Reactor. Measurements of γ-ray ( 239 Np via 239 U) were performed with each sample and standard after cooling for about three days. Compared with a non-destructive thermal NAA, the present method was found to improve the sensitivity because it reduced the intense Compton background induced by 24 Na. Uranium in coral standards was determined within 2% of analytical precision. The data obtained for the carbonate standards are mostly consistent with reported values. The present method could be usefully applied to determine uranium contents in fossil corals from the Funafuti Atoll in the Pacific. The distribution of uranium between seawater and coral skeletons is also discussed in order to understand the environmental media in which the coral grew. (author)

  19. Substoichiometric determination of chromium by neutron activation analysis

    International Nuclear Information System (INIS)

    Kudo, K.; Shigematsu, T.; Kobayashi, K.

    1977-01-01

    A method of radioactivation analysis has been developed for the determination of chromium. It is based on the substoichiometric extraction of chromium diethyldithiocarbamate into methyl-isobutyl-ketone from acetate buffer solution in the presence of EDTA and potassium cyanide. A solution of NaDDC was prepared by dissolving an appropriate amount of GR grade salt in bidistelled water. The concentration of NaDDC was determined by substoichiometric isotope dilution method using 64 Cu or sup(114m)In tracer of known specific activity. The extraction of chromium is not influenced by the presence of EDTA or potassium cyanide while the extraction of chromium is inhibited in tartrate or citrate solution. All metal ions examined are extracted by NaDDC together with chromium and become to interfere for the substoichiometric extraction of chromium. This can be avoided, however, by the addition of EDTA except for copper and silver. The method has been applied for the determination of chromium in high-purity calcium carbonate and NBS glasses as standard reference materials. (T.G.)

  20. Chemotherapeutics-resistance "arms" race: An update on mechanisms involved in resistance limiting EGFR inhibitors in lung cancer.

    Science.gov (United States)

    Singh, Pankaj Kumar; Silakari, Om

    2017-10-01

    Clinical reports suggest that EGFR-mutated lung cancer usually respond significantly towards small molecule tyrosine kinase inhibitors. Same studies also report the eventual development of acquired resistance within a median time interval of 9 to 14months. One of the major mechanisms involved in this acquired resistance was found to be a secondary point mutation at gate-keeper residue, EGFR T790M. However, there are other recent studies which disclose the role of few other novel key players such as, ZEB1, TOPK etc., in the development of tolerance towards the EGFR TKI's, along with other commonly known mechanisms, such as amplification of signalling pathways such as, c-MET, Erbb2, AXL, additional acquired secondary mutations (PIK3CA, BRAF), or phenotypic transformation (small cell or epithelial to mesenchymal transitions). Interestingly, a recent study showed development of resistance via another point mutation, C797S, in case of tumors which were previously resistant and were administered agents capable of overcoming T790M gatekeeper mutation based resistance. Thus, raising serious concern over the direction of drug development involving tyrosine kinases such as EGFR. Current approaches focussing on development of third generation inhibitors, dual inhibitors or inhibitors of HSP90 have shown significant activity but do not answer the long term question of resistance. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Research Progress of the Resistance Mechanism of Non-small Cell Lung Cancer 
to EGFR-TKIs

    Directory of Open Access Journals (Sweden)

    Huihui LIU

    2013-10-01

    Full Text Available Nowadays, lung cancer is the malignant tumor of the highest morbidity and mortality over the world, and non-small cell lung cancer (NSCLC makes up about 80%. There is a great many NSCLC patients have been in advanced stage when diagnosed. As a result, people pay more attention to curing advanced NSCLC. The standard treatment to advanced NSCLC is platinum-based combined chemotherapy. However, chemotherapy drugs usually have limited effects on improving the survival of the patients. Then exploring new therapies is extremely urgent to us. Now, molecular targeted therapy has been the most promising research area for the treatment of NSCLC with researches going deep into pathogenesis and biological behavior of lung cancer. Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs have achieved a great success in the treatment of advanced NSCLC. Their representatives are erlotinib and gefitinib. The two drugs have been widely used to treat advanced NSCLCs worldwide, especially for the patients with EGFR activating mutations. However, after a period of treatment (median time is 6 to 12 months, most patients will develop drug resistance to EGFR-TKIs. Intense research in these NSCLCs has identified two major mechanisms of resistance to TKIs: primary and acquired resistances. The research about resistance mechanism of NSCLC to EGFR-TKIs is a hot one because of their excellent effects on improving overall and progression-free survival. The aim of this article was to summarize the development of the resistance mechanisms.

  2. Correlation between egfr expression and accelerated proliferation during radiotherapy of head and neck squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Pedicini Piernicola

    2012-08-01

    Full Text Available Abstract Purpose To investigate the correlation between the expression of Epidermal Growth Factor receptor (EGFr and the reduction of the effective doubling time (TD during radiotherapy treatment and also to determine the dose per fraction to be taken into account when the overall treatment time (OTT is reduced in accelerated radiotherapy of head and neck squamous cell carcinoma (HNSCC. Methods A survey of the published papers comparing 3-years of local regional control rate (LCR for a total of 2162 patients treated with conventional and accelerated radiotherapy and with a pretreatment assessment of EGFr expression, was made. Different values of TD were obtained by a model incorporating the overall time corrected biologically effective dose (BED and a 3-year clinical LCR for high and low EGFr groups of patients (HEGFr and LEGFr, respectively. By obtaining the TD from the above analysis and the sub-sites’ potential doubling time (Tpot from flow cytometry and immunohistochemical methods, we were able to estimate the average TD for each sub-site included in the analysis. Moreover, the dose that would be required to offset the modified proliferation occurring in one day (Dprolif, was estimated. Results The averages of TD were 77 (27-9095% days in LEGFr and 8.8 (7.3-11.095% days in HEGFr, if an onset of accelerated proliferation TK at day 21 was assumed. The correspondent HEGFr sub-sites’ TD were 5.9 (6.6, 5.9 (6.6, 4.6 (6.1, 14.3 (12.9 days, with respect to literature immunohistochemical (flow cytometry data of Tpot for Oral-Cavity, Oro-pharynx, Hypo-pharynx, and Larynx respectively. The Dprolif for the HEGFr groups were 0.33 (0.29, 0.33 (0.29, 0.42 (0.31, 0.14 (0.15 Gy/day if α = 0.3 Gy-1 and α/β = 10 Gy were assumed. Conclusions A higher expression of the EGFr leads to enhanced proliferation. This study allowed to quantify the extent of the effect which EGFr expression has in terms of reduced TD and Dprolif for each head and neck

  3. A nuclear data library for activity determinations of selected nuclides

    International Nuclear Information System (INIS)

    Baard, J.H.

    1991-11-01

    This report describes the GAMLIB 1-5 library, which is used in the calculation of the activity of radionuclides present in the gamma-ray spectra of irradiated neutron fluence detectors. The library contains all constants needed to calculate the activity for reactions normally applied in neutron fluence determinations, performed in irradiation experiments in the HFR. It also contains the nuclide constants for the activity calculation of gamma-ray measurements of U and Pu samples. The library consists of two kinds of tables, the first containing gamma-ray energies and gamma-ray emission probabilities with their uncertainties and the nuclide code, the other the nuclide code, decay constant, gamma -ray energies and gamma-ray emission probabilities. No cross-section data are stored in this library. All the relevant dat of the Nuclear Data Guide (Dordrecht, Kluwer 1989) have been used as base for this library. Other data have been obtained from recent literature. This library comprises 155 nuclides and 1115 gamma-ray energies. (author). 9 refs

  4. Equilibrium curve determination of HF adsorption by activated carbon

    International Nuclear Information System (INIS)

    Bahrami, H.; Safdari, S. J.; Mousavian, S. M. A.

    2010-01-01

    One of the byproducts of uranium enrichment industry is hydrogen fluoride gas. Due to the toxicity and corrosivity of the molecule, it has adverse effects on the environment and the process. Therefore, it must be removed by adsorption towers. The activated carbon is one of the proposed sorbent for the adsorption. Hydrogen fluoride adsorption equilibrium curve gives important information for designing the adsorption towers. In this article, the hydrogen fluoride adsorption and adsorption factors were determined experimentally, and four different types of carbon have been used. The operating pressure in all tests was less than 30 mbar. Comparison between the obtained experimental equilibrium curves shows that the first, second and fourth types of activated carbon are suitable for the adsorption of hydrogen fluoride. The experimental data were fitted using mathematical models of Langmuir, Freundlich, Toth and Henry. The results show that Toth mathematical model is more suitable than other models. Also, the absolute error were predicted by the model of Toth for the first, second and fourth types of the activated carbon were 12.9, 16.5 and 34 percent, respectively.

  5. A gasometric method to determine erythrocyte catalase activity

    Directory of Open Access Journals (Sweden)

    A.J.S. Siqueira

    1999-09-01

    Full Text Available We describe a new gasometric method to determine erythrocyte catalase activity by the measurement of the volume of oxygen produced as a result of hydrogen peroxide decomposition in a system where enzyme and substrate are separated in a special reaction test tube connected to a manometer and the reagents are mixed with a motor-driven stirrer. The position of the reagents in the test tube permits the continuous measurement of oxygen evolution from the time of mixing, without the need to stop the reaction by the addition of acid after each incubation time. The enzyme activity is reported as KHb, i.e., mg hydrogen peroxide decomposed per second per gram of hemoglobin (s-1 g Hb-1. The value obtained for catalase activity in 28 samples of hemolyzed human blood was 94.4 ± 6.17 mg H2O2 s-1 g Hb-1. The results obtained were precise and consistent, indicating that this rapid, simple and inexpensive method could be useful for research and routine work.

  6. 2-Triazenoazaindoles: α novel class of triazenes inducing transcriptional down-regulation of EGFR and HER-2 in human pancreatic cancer cells.

    Science.gov (United States)

    Kreutzer, Jan N; Salvador, Alessia; Diana, Patrizia; Cirrincione, Girolamo; Vedaldi, Daniela; Litchfield, David W; Issinger, Olaf-Georg; Guerra, Barbara

    2012-04-01

    Pancreatic cancer is a complex malignancy arising from the accumulation of genetic and epigenetic defects in the affected cells. Standard chemotherapy for patients with advanced disease shows only modest effects and is associated with considerable toxicity. Overexpression or aberrant activation of members of the epidermal growth factor receptor tyrosine kinase family, which includes EGFR and HER-2, occurs frequently and is associated with multiple drug resistance and decreased patient survival. In this study, we have investigated the therapeutic potential of AS104, a novel compound of the triazene class, with potential inhibitory effects on EGFR. We found that treatment of cells with AS104 causes significant reduction of cell growth and metabolic activity in four human pancreatic cancer cell lines. Furthermore, we show that the AS104-mediated induction of apoptotic cell death is associated with stimulation of autophagy in a dose-dependent manner. Treatment of cells with AS104 results in significant down-regulation of EGFR and HER-2 expression and activity and subsequent inhibition of downstream signaling proteins. Quantitative RT-PCR analysis and assays with proteasome inhibitors revealed that AS104 regulates the expression of EGFR and HER-2 at the transcriptional level. These findings provide for the first time experimental evidence for efficacy of AS104 in the simultaneous transcriptional repression of EGFR and HER-2 genes and suggest that AS104 may have therapeutic potential in the treatment of pancreatic cancers that express high levels of the aforementioned receptor tyrosine kinases.

  7. 2-Triazenoazaindoles: A novel class of triazenes inducing transcriptional down-regulation of EGFR and HER-2 in human pancreatic cancer cells

    Science.gov (United States)

    KREUTZER, JAN N.; SALVADOR, ALESSIA; DIANA, PATRIZIA; CIRRINCIONE, GIROLAMO; VEDALDI, DANIELA; LITCHFIELD, DAVID W.; ISSINGER, OLAF-GEORG; GUERRA, BARBARA

    2012-01-01

    Pancreatic cancer is a complex malignancy arising from the accumulation of genetic and epigenetic defects in the affected cells. Standard chemotherapy for patients with advanced disease shows only modest effects and is associated with considerable toxicity. Overexpression or aberrant activation of members of the epidermal growth factor receptor tyrosine kinase family, which includes EGFR and HER-2, occurs frequently and is associated with multiple drug resistance and decreased patient survival. In this study, we have investigated the therapeutic potential of AS104, a novel compound of the triazene class, with potential inhibitory effects on EGFR. We found that treatment of cells with AS104 causes significant reduction of cell growth and metabolic activity in four human pancreatic cancer cell lines. Furthermore, we show that the AS104-mediated induction of apoptotic cell death is associated with stimulation of autophagy in a dose-dependent manner. Treatment of cells with AS104 results in significant down-regulation of EGFR and HER-2 expression and activity and subsequent inhibition of downstream signaling proteins. Quantitative RT-PCR analysis and assays with proteasome inhibitors revealed that AS104 regulates the expression of EGFR and HER-2 at the transcriptional level. These findings provide for the first time experimental evidence for efficacy of AS104 in the simultaneous transcriptional repression of EGFR and HER-2 genes and suggest that AS104 may have therapeutic potential in the treatment of pancreatic cancers that express high levels of the aforementioned receptor tyrosine kinases. PMID:22134789

  8. Fluorescent Affibody Molecule Administered In Vivo at a Microdose Level Labels EGFR Expressing Glioma Tumor Regions.

    Science.gov (United States)

    de Souza, Ana Luiza Ribeiro; Marra, Kayla; Gunn, Jason; Samkoe, Kimberley S; Hoopes, P Jack; Feldwisch, Joachim; Paulsen, Keith D; Pogue, Brian W

    2017-02-01

    Fluorescence guidance in surgical oncology provides the potential to realize enhanced molecular tumor contrast with dedicated targeted tracers, potentially with a microdose injection level. For most glioma tumors, the blood brain barrier is compromised allowing some exogenous drug/molecule delivery and accumulation for imaging. The aberrant overexpression and/or activation of epidermal growth factor receptor (EGFR) is associated with many types of cancers, including glioblastoma, and so the use of a near-infrared (NIR) fluorescent molecule targeted to the EGFR receptor provides the potential for improving tumor contrast during surgery. Fluorescently labeled affibody molecule (ABY-029) has high EGFR affinity and high potential specificity with reasonably fast plasma clearance. In this study, ABY-29 was evaluated in glioma versus normal brain uptake from intravenous injection at a range of doses, down to a microdose injection level. Nude rats were inoculated with the U251 human glioma cell line in the brain. Tumors were allowed to grow for 3-4 weeks. ABY-029 fluorescence ex vivo imaging of brain slices was acquired at different time points (1-48 h) and varying injection doses from 25 to 122 μg/kg (from human protein microdose equivalent to five times microdose levels). The tumor was most clearly visualized at 1-h post-injection with 8- to 16-fold average contrast relative to normal brain. However, the tumor still could be identified after 48 h. In all cases, the ABY-029 fluorescence appeared to localize preferentially in EGFR-positive regions. Increasing the injected dose from a microdose level to five times, a microdose level increased the signal by 10-fold, and the contrast was from 8 to 16, showing that there was value in doses slightly higher than the microdose restriction. Normal tissue uptake was found to be affected by the tumor size, indicating that edema was a likely factor affecting the expected tumor to normal tissue contrast. These results suggest

  9. Computational design of binding proteins to EGFR domain II.

    Directory of Open Access Journals (Sweden)

    Yoon Sup Choi

    Full Text Available We developed a process to produce novel interactions between two previously unrelated proteins. This process selects protein scaffolds and designs protein interfaces that bind to a surface patch of interest on a target protein. Scaffolds with shapes complementary to the target surface patch were screened using an exhaustive computational search of the human proteome and optimized by directed evolution using phage display. This method was applied to successfully design scaffolds that bind to epidermal growth factor receptor (EGFR domain II, the interface of EGFR dimerization, with high reactivity toward the target surface patch of EGFR domain II. One potential application of these tailor-made protein interactions is the development of therapeutic agents against specific protein targets.