bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 62: Alteration of metabolic pathways of glucose consumption by CENU treatment in B16 melanoma tumors: A NMR spectroscopy-based [1,2-13C]glucose fluxomics analysis
Authors: Morvan Daniel , Fages Anne , Schwartz Laurent , Steyaert Jean Marc , Stepien Georges , Demidem Aicha 
Published: February 2011

Abstract
We have previously shown using proton NMR spectroscopy-based metabolomics that mice bearing B16 melanoma tumors treated by chloroethylnitrosourea (CENU) had a strong intratumoral decrease in glycolysis involving the accumulation of intracellular glucose and glucose-6-phosphate, together the accumulation of glutamate derivatives, despite no significant lactate content change (1).
To get insights into the metabolic pathway followed by glucose carbons in CENU-treated tumor, we used double labelled glucose ([1,2-13C]glucose) and investigated the obtained isotopomers of lactate, the final product of glycolysis. Mice bearing B16 melanoma tumors were treated by CENU or saline solution (control) at days 11, 14 and 17 at dose 15µg/g weight. At day 23, mice were injected intraperitoneally with [1,2-13C]glucose at 25 mg in 150µl saline solution. Animals were sacrificed 30 minutes after glucose injection. Tumors were removed and kept at −80°C until use. The analysis of lactate isotopomers, a fluxomics approach, was done at 500 MHz using high resolution magic angle spinning (HRMAS) 1H-NMR spectroscopy by exploiting 1H-13C coupling signals. The two lactate signals, the methyl (C3) signal centered at 1.33 ppm and the methine (C2) signal centered at 4.12 ppm were differentially analyzed, and quantified from spectra witout and with broadband 13C-decoupling. In addition, the activity of pyruvate-kinase was measured using enzyme assay.
In comparison with control tumors, CENU-treated tumors exhibited an overall decrease of labelled lactate both at C3 and C2 position, together with a significant increase in the relative proportion of C2 to C3 labelling (0.65±0.10 vs 0.91±0.13, P&lt;0.01, n=3 vs n=3). Because lactate only labelled on C3 was a product of glucose metabolism through the pentose phosphate pathway, it was concluded that most of glucose in CENU-treated tumors was directly metabolized to lactate, thus dedicated to ATP production rather than macromolecular biosynthesis. Consistently, the activity of pyruvate kinase, the main source of glycolysis-derived ATP was increased under CENU treatment (+48%, P&lt;0.01).
Altogether these fluxomics data provide evidence of glycolysis adaptation that may be correlated to reduced proliferation, decreased aggressiveness, and redifferentiation, as previously shown in this model (2). In addition, this study suggests that metabolic targeting of glycolysis-related ATP production may improve CENU efficacy.
1- Morvan D, Demidem A. Cancer Res, 67; 2150-59, 2007
2- Demidem A et al. Cancer Res, 61; 2294-300, 2001
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 62.
Abstract 629: Hepatocyte growth factor induces resistance to an irreversible epidermal growth factor receptor inhibitor in EGFR-T790M mutant lung cancer
Authors: Yamada Tadaaki , Matsumoto Kunio , Donev Ivan Shterev , Sekido Yoshitaka , Nishioka Yasuhiko , Sone Saburo , Yano Seiji 
Published: February 2011

Abstract
Purpose:
Epidermal growth factor receptor (EGFR)-activating mutations, such as deletion in exon 19 and L858R point mutation in exon 21,were found in non-small cell lung cancer and associated with favorable response to the reversible EGFR tyrosine kinase inhibitors (EGFR-TKI), gefitinib and erlotinib. However, almost all NSCLC patients with EGFR mutations who show response to reversible EGFR-TKI ultimately develop resistance to these agents.
Recently, several mechanisms were reported to induce acquired resistance to reversible EGFR-TKI for non-small cell lung cancer with EGFR-activating mutations. Of these, the secondary T790M mutation in EGFR is the most frequent cause of acquired resistance to the reversible EGFR-TKI.
Irreversible EGFR-TKIs are expected to overcome the reversible EGFR-TKI resistance of lung cancer harboring T790M mutation in EGFR. However, it is clear that resistance may also develop to this class of inhibitors. We showed previously that hepatocyte growth factor (HGF) induced gefitinib resistance of lung cancer harboring EGFR-activating mutations.
Here, we investigated whether HGF induced resistance to the irreversible EGFR-TKI, CL-387,785, in lung cancer cells (H1975) harboring both L858R activating mutation and T790M secondary mutation in EGFR.
Experimental Design:
CL-387,785 sensitivity and signal transduction in H1975 cells were examined in the presence or absence of HGF or HGF-producing fibroblasts with or without HGF-MET inhibitors.
Results:
HGF induces resistance to CL-387,785 in H1975 cells. Western blotting and small interfering RNA analyses indicated that HGF-induced resistance was mediated by the MET/phosphoinositide 3-kinase/Akt signaling pathway independent of EGFR, ErbB2, ErbB3, and ErbB4. Resistance of H1975 cells to CL-387,785 was also induced by coculture with high-level HGF-producing lung fibroblasts. The resistance was abrogated by treatment with anti-HGF neutralizing antibody, HGF antagonist NK4, or MET-TKI.
Conclusions:
We showed HGF-mediated resistance as a novel mechanism of resistance to irreversible EGFR-TKIs. Our findings provide a novel insight into the involvement of HGF-MET mediated signaling in de novo and acquired resistance to irreversible EGFR-TKIs in lung cancer harboring T790M mutation in EGFR.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 629.
Abstract 635: Triggering cancer cell death using light-inactivation of the Ki-67 protein
Authors: Rahmanzadeh Ramtin , Rai Prakash , Rizvi Imran , Celli Jonathan , Abu-Yousif Adnan , Baron-Lühr Bettina , Gerdes Johannes , Hasan Tayyaba 
Published: February 2011

Abstract
INTRODUCTION: Specific destruction of cancer cells can reduce the acute systemic toxicity associated with current treatments. This can be achieved by targeting key molecular markers implicated in cancer cell growth. One such marker associated with cell proliferation is the Ki-67 protein (pKi-67) and is highly expressed in cancer cells. However it is a protein that resides inside the nuclei of cells and thus targeting it has been a challenge so far. Here, we show an innovative proof-of-principle approach for efficient killing of proliferating ovarian cancer cells by photoinactivation of pKi-67 with nanotechnology-based photodynamic therapy (PDT). METHODS: Anti pKi-67 antibodies were conjugated to fluorescein isothiocyanate (FITC) which is used as a photoactivatable agent. These conjugates were then encapsulated inside liposomes for intracellular delivery. The efficacy of Ki-67 targeting was evaluated using two in vitro models of ovarian cancer, monolayer cultures and 3D cultures established in our lab. Cell viability after irradiation with laser light at 488 nm was assessed using MTT viability assay for monolayer cultures while a Live/Dead assay kit was used for analyzing 3D cultures. RESULTS: First we demonstrated the delivery of pKi-67 antibodies to the nucleoli of ovarian cancer cells with liposomal constructs. Irradiation of these cells with a 488 nm laser led to a significant loss of viability when pKi-67 was targeted with the TuBB-9-FITC antibodies. The antibody TuBB-9 recognizes a fraction of pKi-67, which is involved in ribosomal RNA synthesis. The efficacy of this approach was also demonstrated in a 3D culture model of OVCAR-5 cells. Incubation of 3D cultures with the liposomal constructs followed by light irradiation led to destruction of their acinar structures over 72 h following treatment. Analysis of cell killing with dependence on acinar size showed that largest acini responded best to the treatment. The specificity of this approach was demonstrated in confluent human lung fibroblasts (MRC-5) where only a small population expresses pKi-67 and consistent with our hypothesis, minimal cell death was observed here. CONCLUSIONS: Our findings suggest that pKi-67 is an attractive therapeutic target in cancer. This approach allows destruction of the most aggressive cancer cells and holds promise as an effective alternative treatment.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 635.
Abstract 636: Role of Prostaglandin E2 in breast-cancer associated lymphangiogenesis in an in vitro system
Authors: Girish Gannareddy V. , Radan Lida , Tutunea-Fatan Elena , Majumder Mousumi , Bhattacharjee Rabindra , Xin Xiping , Lala Neena , Lala Peeyush K. 
Published: February 2011

Abstract
Lymphatic metastasis is a common occurence in breast cancer. Molecular mechanisms in breast cancer-associated lymphangiogenesis and lymphatic metastasis are poorly defined. We had earlier shown that elevated cyclo-oxygenase (COX)-2 expression by human as well as murine breast cancer cells promotes tumor progression and metastasis by multiple mechanisms: inactivation of host anti-tumor immune cells, stimulation of tumor cell migration and tumor-associated angiogenesis. Furthermore, COX-2 was causally associated with increased VEGF-C expression/secretion in human and murine breast cancer cell lines, thus promoting tumor-associated lymphangiogenesis. VEGF-C production was partially dependent on endogenous PGE-2 mediated activation of EP4 receptors on breast cancer cells thus making EP4 a good therapeutic target. It was unclear whether tumor or host derived PGE-2 had any direct effect on lymphangiogenesis, and if so, whether EP4 receptors on lymphatic endothelial cells played any role. To address these questions, we devised an in vitro lymphangiogenesis assay using a LYVE-1 expressing rat mesenteric lymphatic endothelial cell line (RMLEC) plated on growth factor- reduced Matrigel. Endothelial tube formation by RMLEC was rapidly induced in 12-18 hours after plating on Matrigel even under serum-free conditions, whereas plating them on collagen gel even in the presence of serum did not induce any tube formation. This suggested the presence of some inducing factor(s) in the Matrigel, possibly also present in the ECM in vivo. Matrigel-induced tube formation was completely abrogated in the presence of COX 1/2 inhibitor indomethacin (10mM), COX-2 inhibitor NS-398 (15mM), and a selective EP4 antagonist CJ-042794 (2.5 mM). In each case, an additional presence of PGE2 (1 µM) or an EP4 agonist PGE-1 alcohol (1µM) completely restored the tube formation on matrigel. A similar restoration was also achieved in the presence of serum-free conditioned media (24 h culture) of a COX-2 expressing murine breast cancer cell line C3L5 that induces lymphangiogenesis in vivo. These results indicate the roles of tumor as well as host-derived PGE2 in inducing lymphangiogenesis possibly by activating COX-2/EP4 receptors on lymphatic endothelial cells. Further studies are in progress to identify the tube-inducing component(s) in the Matrigel and C3L5 cell conditioned medium. (Supported by grants from the Canadian Breast Cancer Foundation, Ontario chapter and the Ontario Institute of Cancer Research to PKL. The gift of the RMLEC from Dr Sophia Ran, Southern Illinois Univ School of Medicine is gratefully acknowledged).
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 636.
Abstract 640: SIRT2 deacetylates peroxiredoxin and increases sensitivity to oxidative stress in human breast cancer cells
Authors: CoothanKandaswamy Veena , Chen Jianguang , Joshi Atul , Rao Rekha , Fiskus Warren , Buckley Kathleen M. , Nalluri Srilatha , Bhalla Kapil N. 
Published: February 2011

Abstract
SIRT2, the mammalian ortholog of yeast Hst2, is a predominantly cytosolic and nuclear member of sirtuins, which is the class III, NAD+ dependent, histone deacetylase (HDAC) family. Sirtuins play a key role in modulating cellular stress resistance, longevity and cancer transformation. SIRT2 is known to deacetylate FOXO1 and FOXO3, thereby regulating FOXO-regulated stress resistance. In the cytosol, SIRT2 co-localizes with microtubules and deacetylates α-tubulin at the lysine-40, indicating a role in proper cytokinensis. Here, we determined other biologically important SIRT2 targets and their functions. Knockdown and overexpression of SIRT2 in HEK293 cells significantly altered the acetylation status of many proteins, including a group of proteins ranging in molecular weight from 23-50 kDa. In cells with knockdown of SIRT2, differential in-gel electrophoresis of cytosolic extract of cells followed by mass spectrometric analysis identified several significantly hyper-acetylated proteins, notably peroxiredoxin 1. Peroxiredoxins are ubiquitous family of evolutionarily conserved, thiol-dependent peroxidases, which catalyze the reduction of hydrogen peroxide. SIRT2 co-immunoprecipitated with peroxiredoxin 1, and ectopic overexpression of SIRT2 attenuated acetylation of peroxiredoxin 1 in HEK 293 cells. While acetylation activates, reduced acetylation is known to inhibit the activity of peroxiredoxins. Ectopic overexpression of SIRT2, but not the catalytically dead SIRT2 mutant, markedly increased reactive oxygen species (ROS) levels as well as increased the sensitivity of the human breast cancer MCF7 and MDA MB231 cells to oxidant stress induced by hydrogen peroxide. SIRT2 overexpression in breast cancer cells also increased their sensitivity to ROS generating agents such as arsenic trioxide and menadione. These findings demonstrate that SIRT2 plays an important role in regulating oxidative stress in cells by modulating the activity of peroxiredoxin 1. The findings also highlight the possibility that increased SIRT2 levels and activity can be therapeutically exploited for augmenting the antitumor effects of therapeutic agents that induce cancer cell death by increasing intracellular ROS levels.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 640.
Abstract 646: Identification of FURIN as a tumor maintenance gene in solid tumors by in vivo Retroviral Mutagenesis and Directed Complementation
Authors: Lorena Lerner , Liu Qing , Yang John , Krieger Brian , Tao Nianjun , Zarycki Jodi , You Fanglei , Kabbarah Omar , Robinson Murray O. , Chiu M. Isabel 
Published: February 2011

Abstract
To identify tumor maintenance genes and pathways, we applied a genome-wide, large-scale functional screening approach using retrovirus-mediated mutagenesis on a number of inducible murine solid tumor models, including a HER2-driven breast tumor model and kRAS-driven breast and lung cancer models, in which viral integration could maintain established tumors in the absence of the initiating oncogene.
We identified more than 3,000 recurrent viral integration sites in a collection of about 400 tumors. Whereas some genes were targeted by viral integration in specific tumor models, others were prominently hit in all the models. For example, insertions targeting the Furin locus were detected in tumors from all three models. In such tumors, viral integrations mapped to the Furin promoter consistent with the notion that activation of this gene and/or pathway may represent a common mechanism of tumor maintenance.
Using our inducible directed complementation (DC) platform, we show that introduction of a wild type FURIN cDNA can maintain primary tumors in vivo in the absence of the initial driving oncogene. The FURIN DC tumors provide a useful pre-clinical model with which we can examine the effects of FURIN antagonists on tumor maintenance. Next, we sought to extend the utility of these validated DC tumor models to drug discovery by establishing FURIN-dependent cell lines for high-throughput screening.
Here we describe detailed molecular characterization of the FURIN DC tumor models as well as from the cell lines derived from these tumor models. Furthermore, FURIN DC Tumor Models as wells as cell lines serve as a unique experimental tools, with which response to novel targeted therapies and other cancer agents can be studied.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 646.
Abstract 654: High-throughput RNAi screening for the identification of genes that potentiate paclitaxel response in metastatic breast cancer
Authors: Henderson Meredith C. , Gonzales Irma M. , Arora Shilpi , Peralta Lourdes , Little Tanya H. , Choudhary Ashish , Azorsa David O. 
Published: February 2011

Abstract
In the United States, metastatic breast cancer is currently the second leading cause of death in women after lung cancer and it has been estimated that over 400,000 women worldwide die from the disease each year. Two chemotherapeutic agents that have shown much promise in treatment of metastatic breast cancer are paclitaxel and docetaxel, both being members of a class of drugs known as taxanes. Although the current regimens in the treatment of metastatic breast cancer often include one of these taxanes, the overall response rate is between 30-60%, indicating that about half the patients that receive treatment for metastatic breast cancer do not respond. In order to improve paclitaxel response in breast cancer cells, we employed a functional genomics based approach, utilizing high-throughput RNAi (HT-RNAi) to identify genes that, when silenced, would sensitize breast cancer cells to paclitaxel. The HT-RNAi assay was developed to quantify the growth inhibition of MDA-MB-231 breast cancer cells transfected with siRNA and treated with an EC30 dose of paclitaxel. For screening, MDA-MB-231 cells were reverse-transfected with siRNA from a library targeting 7000 druggable genes (2 siRNA per gene). Twenty-four hours after siRNA transfection, an EC30 dose of paclitaxel was added and cell viability was assessed after 72 hours of drug exposure. The data was analysed using the B-score method. Following data analysis, we generated a list of “gene targets”, which upon silencing individually, lead to potentiation of paclitaxel in breast cancer cells. Validation of these genes will identify potential therapeutic targets for novel paclitaxel combinations in order to improve clinical efficacy. Furthermore, these findings demonstrate the effectiveness of using HT-RNAi as a tool for identifying sensitizing targets to chemotherapeutic agents.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 654.
Abstract 658: Identification of a molecular signature after L-methionine treatment in MCF-7 and LNCaP cancer cells
Authors: Benavides Max A. , Hu Dong , Baraoidan Marie K. , Bruno Annette , Du Pan , Lin Simon , Yang Wancai , Bland Kirby I. , Grizzle William E. , Bosland Maarten C. 
Published: February 2011

Abstract
Our previous research has shown that the essential sulfur-amino acid methionine inhibited proliferation of breast and prostate cancer cell lines, concomitant with p53 modification. The aim of this study was to increment understanding of the mechanisms underlying these effects by determining the influence of L-methionine on functional molecular signatures in these cell lines. Wild-type p53-expressing MCF-7 (breast cancer) and LNCaP (prostate cancer) cells were treated with L-methionine (5mg/ml) for 72hrs. Changes in molecular signatures of these cells were examined by microarray analysis of 15,814 probes in triplicate samples. Genes with significant expression changes were identified by False Discovery Rate analysis (p-value &lt; 0.01; fold-change &gt; 1.5). In LNCaP cells, 325 genes were up-regulated by methionine treatment and 517 genes down-regulated. In MCF-7 cells, 86 genes were up-regulated by methionine and 135 genes up-regulated. Ninety eight genes were regulated in the same direction by methionine in both cell lines; 10 of these genes were up-regulated (AFF3, AKR1C2, ATF3, C8ORF4, GPX8, LAMA3, RBM4B, NQO1, SH3BGRL, and VAMP5) and 88 genes were down-regulated. The expression of five other genes (H1F0, TNF, CENPN, ACAT2, and DHRS2) was changed in opposite directions in the two cell lines. Increases in expression were verified by quantitative RT-PCR. Several of the up-regulated genes encode proteins involved in cellular redox regulation and many of the down-regulated genes belonged to protein kinase families. These observations suggest that methionine is an enhancer of antioxidant activities and has potential as an anti-cancer agent that targets breast and prostate cancer cells.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 658.
Abstract 666: Regulation of IGF-1 signaling by lysosomal cathepsins in neuroblastoma
Authors: Soori Mehrnoosh , Cartledge Donna , Glazewski Lisa , Lu Guizhen , Mason Robert W. 
Published: February 2011

Abstract
Neuroblastoma is the most common extracranial solid tumor of childhood. Despite intensive combination therapies, the survival rate for children diagnosed with high-risk neuroblastoma remains below 40%, with surviving children suffering from severe side-effects of aggressive surgery, cytotoxic chemotherapy and radiation. We show that specific inhibition of a group of lysosomal proteases results in accumulation of autophagic vacuoles and eventual apoptosis of neuroblastoma cell lines. Cell death is not caused in breast and prostate cancer cell lines or mouse primary fibroblasts, indicating specificity of the apoptotic response in neuroblastoma. In this study we have examined mechanisms by which inhibition of these proteases can lead to the specific death of these tumors. IGF-1 signaling is essential for cellular proliferation, survival, and apoptotic resistance. We found that in neuroblastoma cells IGF-1 signaling is impaired by inhibition of cathepsins B and L. Western blotting shows that lower molecular weight fragments of the IGF-1 receptor beta subunit accumulate in inhibitor-treated cells, indicating that lysosomal proteases are essential for the complete the degradation of the IGF-1 receptor. Phosphorylation and activation of full-length IGF-1 receptor was not modified by inhibitor treatment, but phosphorylation and activation of MAPK and Akt (downstream effectors of IGF-1 receptor signaling) was greatly diminished. Fractionation of cellular lysates showed that the IGF-1R β fragments accumulate in compartments that contain a cleaved form of LC-3, a marker of autophagic vacuoles. Intermediates of the IGF-1 signaling cascade were also sequestered within these compartments, and significantly depleted in the cytoplasm. We conclude that inhibition of lysosomal proteases results in sequestration of critical components of the cell signaling transduction pathway, causing cell death by uncoupling of cell surface and endosomal signaling from intracellular effector signals.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 666.