bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 5222: Molecular imaging of GSK-3β and CK1α kinase activities in response to Wnt signaling
Authors: Nyati Shyam , Bhojani Mahaveer Swaroop , Pasupulathi SwathiChitra , Ross Brian D. , Rehemtulla Alnawaz 
Published: February 2011

Abstract
The Wnt signaling pathway has been found to be disregulated in many carcinomas of gastrointestinal system. GSK-3β and CK1α act as molecular switch that dictates both on and off states of Wnt/beta-catenin signaling by regulating cellular levels of the Wnt effector molecule β-catenin. In the absence of the Wnt signal β-catenin is initially phosphorylated by CK1α at S45, followed by GSK-3β at S41, T37 and S33 which marks it for proteosomal degradation. Although GSK-3β is one of the key regulators of the Wnt signaling pathway, the ability for direct, non-invasive & real-time measurement of its kinase activity has been unavailable. Here we describe a chimeric, gain of function, split luciferase based novel reporter for monitoring of dual kinase (GSK-3β and CK1α) activity.
The N-terminal β-catenin peptide (aa 29-48) harboring phosphorylation sites for GSK-3β and CK1α was synthesized and used to construct bioluminescence β-catenin reporter (BCR). This reporter when expressed in SW620 colon carcinoma cells and treated with LiCl and small molecular inhibitors SB415286 (GSK-3β) and CKI-7 (CK1α), lead to a dose and time dependent increase in the bioluminescence which was validated by western blotting. Cell lines stably expressing mutant reporters exhibited attenuated response to LiCl & SB415286 (S37A mutant) and to CKI-7 (S45A mutant) confirming specificity of the reporter. To quantify the Wnt dependent change in the activity of the reporters, stable cell lines were generated in HEK293 background which has an intact Wnt signaling pathway. The WT reporter cell line showed over two fold induction with Wnt conditioned media while S37A mutant reporter cell line did not show a significant change in reporter activity corroborating the specificity of the reporters.
In mice bearing tumors expressing the wild-type reporter, treatment with LiCl resulted an initial increase in the bioluminescence activity at 4 h which peaked at 7 h. Subsequent imaging revealed oscillations of the bioluminescence activity with a frequency of 14 h and an amplitude that decreased with time. Our reporters provide a powerful, novel tool for sensitive, real time, dynamic, non-invasive monitoring of GSK-3β and CK1α kinase activities in-vitro and in-vivo and have the potential in executing novel therapeutic regimens targeting GSK-3β/CK1α.
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 5222.
Abstract 5225: Pemetrexed induced thymidylate synthase inhibition in non-small cell lung cancer in vivo: a pilot study with 18F-FLT PET
Authors: Frings Virginie , van der Veldt Astrid AM , Lubberink Mark , Herder Judith , Peters Godefridus J. , Honeywell Richard , Thunnissen Frederik BJM , Hoekstra Otto S. , Smit Egbert F. 
Published: February 2011

Abstract
Objectives Thymidylate synthase (TS) is a key enzyme for de novo synthesis of DNA and as such a target for anticancer drugs. In a mouse model, effective TS inhibition resulted in a 1.8 fold increase of 3′-deoxy-3′-[(18)F]fluorothymidine (18F-FLT) cellular uptake (Cancer Res 2006;66:8558-64). Here we investigated changes in 18F-FLT uptake 4 hours after the first dose of pemetrexed in patients with non-small cell lung cancer (NSCLC).
Methods Twelve NSCLC patients (mean age 64 yrs, 4 male) treated with pemetrexed (in combination with cisplatin, carboplatin or monotherapy) were included. Patients underwent dynamic 18F-FLT PET at baseline and 4 hours after the first therapeutic dose of pemetrexed. For primary tumors, regions of interest (ROI) were defined with a 41, 50 and 70% threshold of the maximum pixel, and the maximum standardized uptake value (SUVmax) was determined (as well as full kinetic analysis). One, 2, 3, 4 and 6 hours after pemetrexed administration, blood samples were collected to measure deoxyuridine levels using LCMSMS. After six weeks, RECIST was used to evaluate tumor response. Association between 18F-FLT uptake and RECIST was tested with a chi-square test.
Results According to RECIST 3 patients had PR, 7 SD and 2 PD. Four hours after administration of pemetrexed, two patients had increased 18F-FLT uptake (beyond test-retest borders, 22% for SUVmax), while three patients had a significantly decreased uptake (see Table). In 7 out of 12 patients, the change in 18F-FLT uptake was within the test-retest variability. In all patients deoxyuridine levels raised after administration of pemetrexed with a average maximum at 4 hours. There was no significant association between 18F-FLT uptake and RECIST.
Conclusions Measuring TS inhibition in a clinical setting 4 hours after pemetrexed revealed a non-systematic change in 18F-FLT uptake. The association with response measurement on CT was not significant.18F-FLT PET and RECIST per patientPt No.Baseline 18F-FLT uptake (SUVmax)18F-FLT uptake 4 hours after pemetrexed (SUVmax)Change 18F-FLT in uptake (%)RECIST after 6 weeks14.74.94.1SD24.44.75.0SD34.12.3−44.7SD44.04.411.0PD53.54.528.6PR63.42.2−33.3SD74.85.05.7SD812.57.9−36.6PR911.312.17.1PD105.67.228.3SD115.15.35.7PR124.73.7−21.5SD
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 5225.
Abstract 5230: In vivo imaging of tumor malignancy with near-infrared fluorescence probes specific to HIF-active cells
Authors: Kuchimaru Takahiro , Kadonosono Tetsuya , Ushiki Takashi , McDougall Mark , Kizaka-Kondoh Shinae , Hiraoka Masahiro 
Published: February 2011

Abstract
In solid tumors, the distribution of oxygen pressure is not homogenous because of the uncontrolled tumor growth and immature blood vessels during angiogenesis, which generate a hypoxic microenvironment. Tumor hypoxia causes resistance to radiotherapy and chemotherapy, and malignant progression Hypoxia-inducible factor-1 (HIF-1) is a master transcriptional regulator for adaptation to hypoxia by inducing more than 100 genes, which are closely associated with malignant phenotype. Thus, HIF-1-active cells are hallmark of malignant tumors. We have been developing fusion protein probes specific to HIF-1-active microenvironment for imaging and targeting malignant tumors. We recently constructed a fusion protein POH, which consisted of Protein Transduction Domain (PTD), Oxygen-dependent Degradation Domain (ODD) and HaloTag. The PTD was a membrane-permeable peptide, which efficiently delivered fusion proteins into cells. The ODD was responsible for the oxygen-dependent regulation of the probe, which stabilized in a hypoxic environment and degraded immediately under normoxic conditions. In addition, HaloTag was used to covalently conjugate with its specific ligand labeled with near-infrared fluorescence (NIRF) dye. POH-NIRF was examined for its target-specificity and in vivo dynamic status by in vivo and ex vivo fluorescence imaging with IVIS-SPECTRUM. To visualize the targets in vivo, we used bioluminescence imaging of tumor cells, which stably retained a HIF-1-dependent luciferase reporter gene. POH-NIRF probes successfully imaged HIF-1-active regions defined by bioluminescence imaging in subcutaneously implanted human xenograft tumors and orthotopic pancreatic cancers 9 to 24 hrs after POH-NIRF injection. Furthermore, immunohistochemical analysis of tumor sections from the mice 6h after POH-NIRF injection revealed the regions imaged with POH-NIFR was overlapped with HIF-1α-positive regions, while the intracellular localization of POH-NIRF was in cytoplasm. Overall results demonstrated that POH-NIRF was a specific probe for HIF-1-active/hypoxic cells and suggested that a PTD-ODD probe would become a unique imaging probe for tumor malignancy.
Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.
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 5230.
Abstract 5233: Imaging breast cancer xenograft using multienergy modality and target-specific molecular agents
Authors: Wang Wei , Qiu Xiuchun , Carmeron Arlin G. , Zhang Siyuan , Yu Dihua , Mawad Michel E. , Shi Ke 
Published: February 2011

Abstract
Interleukin-11 (IL-11) and its receptor (IL-11R) involve in many normal and abnormal biological progress. Studies strongly suggest that interleukin-11 (IL-11) plays an important role in early bone metastases. We synthesized an IL-11Rα homing peptide identified from in vivo patient screening with a peptide phage display and to conjugate it to both an NIR dye for optical imaging and a chelator for nuclear imaging. Cell binding and internalization of the imaging agent was evaluated using NIR confocal microscopy and human breast cancer MDA-MB-231 cell lines. Specificity was demonstrated by comparing with free dye and blocking with the unlabeled recombinant IL-11. Tumor cell growth, vasculature formation and IL-11 agent binding to the tumor were demonstrated in vivo using luciferase positive tumor xenograft model and the injection of both vasculature and IL-11 agents. Tissue autoradiography and H&E staining of the same tissue sections were conducted to verify imaging data. Biodistribution was analyzed by percentage injection dose per gram tissue. Confocal microscopy demonstrated that the target specific imaging agent accumulated on the cell membrane and internalized into cell while free dye had significant lower cell binding than the IL-11 agent. Pre-incubated by the presence of IL-11 protein significantly decreased the agent binding to the cell. Multienergy in vivo imaging revealed the tumor growth, vasculature formation and IL-11 agent binding on the tumor as early as 4 days after the tumor cell inoculation. Overlaid the autoradiography tissue image with H&E staining results demonstrated the heterogeneous distribution of the imaging agent inside tumor mass. Furthermore, the images showed the IL-11 agent only bound to the viable tumor cells. These results suggest a potential imaging agent for study IL-11Rα expression at noninvasive whole body level as well as organ, tissue and cellular levels.
*WW, XQ: These authors contributed equally to this work.
Grant support: DoD W81XWH-08-1-0489, Department of Defense, Department of Radiology research fund, Curtis Hankamer Basic Research Fund and the L.E. and Josephine S. Gordy Memorial Cancer Research Fund, Dan L. Duncan Cancer Center Scholar, American Society for Clinical Oncology and Hope Street Kids Foundation, and National Science Foundation of China grants (30471988, 30973409, and 30873027).
Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.
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 5233.
Abstract 5247: Analysis of stemness gene expression and CD133 abnormal methylation in neuroblastoma cell lines
Authors: Schiapparelli Paula , Enguita Monica , Balbuena Jana , Fan Xing , Lazcoz Paula , Castresana Javier S. 
Published: February 2011

Abstract
Neuroblastoma is the most common extracranial solid tumor of childhood. Cellular heterogeneity is a hallmark of this embryonal malignancy, as distinct neural crest lineages can be found within the same tumor sample.
The aim of our study was to investigate the presence of a subpopulation of immature cells with features of cancer-like stem cells in 12 neuroblastoma cell lines. RT-PCR and flow citometry were performed in order to analyze different kinds of “stemness genes” such as: NESTIN (NES), CD133, SOX-2, BMI1, c-KIT, MELK1, MUSASHI-1 (MSI1), FAS, CD44 and VIMENTIN (VIM). Also, glial and neuronal markers like NCAM1, GFAP and B-TUBULIN III (TUBB3) were analyzed. Interestingly, we found that neuroblastoma cell lines showed a particular pattern of expression suggesting the presence of a subpopulation of immature stem like cancer cells.
Epigenetic changes regarding the CD133 (Prominin-1) promoter gene were also analyzed. This protein has been extensively used to enrich putative cancer propagating stem-like cell populations of different kinds of solid tumors. We found unusual DNA methylation, as 7 of the 12 neuroblastoma cell lines analysed featured a half-methylated state. An increase of RNA and protein levels of CD133 was achieved following demethylation assays using 5-aza-2′-deoxycytidine.
Because cancer stem cells are believed responsible for tumor metastasis, escape from anticancer therapies and disease relapse, their therapeutic targeting and analysis is crucial in neuroblastoma. Also, the regulation of CD133 by epigenetic changes may provide an innovative mechanism of CD133 expression as its regulation still remains unclear.
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 5247.
Abstract 5256: The identification of fatty acid synthase (FASN) as a candidate oncogene and therapeutic target in neuroblastoma
Authors: Mayes Patrick A. , Diskin Sharon , Attiyeh Edward F. , Toporovskaya Yana , Maris John M. 
Published: February 2011

Abstract
Neuroblastoma is a common and lethal pediatric cancer. More than half of patients are at high-risk for relapse and die despite intensive therapy; thus presenting an urgent need for new, rationally designed drugs. To address the need for new therapeutic targets we sought to identify metabolic genes that are critical to neuroblastoma growth and survival. We restricted our analysis to a set of 12 metabolic genes that can be targeted therapeutically and had previously been implicated in other cancers. Analysis of 188 primary human neuroblastomas genotyped on the Illumina HumanHap SNP Array identified high-level, unbalanced gain at the FASN locus (17q25) in 23% of tumors. Analysis of FASN mRNA expression in 99 of these primary neuroblastomas using the IlluminaHT Expression Array identified significant increases in FASN expression restricted to high-risk neuroblastomas with amplification of the MYCN oncogene (P=0.0001). Within the subset of high-risk tumors with MYCN amplification, those that harbored FASN DNA copy number gains showed greater FASN mRNA expression than those with two copy FASN DNA. We next tested siRNAs targeted to the set of 12 metabolic genes in a panel of 12 neuroblastoma cell lines. We found that siRNA inhibition of fatty acid synthase (FASN) and hexokinase 2 (HK2) resulted in significant growth inhibition in 9/12 and 6/12 cell lines, respectively, whereas the others showed no appreciable cytotoxicity. Inhibition of FASN resulted in significant growth inhibition and apoptosis in 8/8 neuroblastoma cell lines with MYCN amplification, suggesting a synthetic lethal effect of FASN inhibition in neuroblastomas with MYCN amplification. Taken together, an integrated genomic and functional analytic approach has identified fatty acid synthase, a key enzymatic mediator of de novo fatty acid metabolism, as a candidate oncogene and therapeutic target in neuroblastoma, especially those harboring MYCN amplification. Ongoing analyses of pharmacologic inhibitors of FASN in neuroblastoma cell line animal models, including impact on global lipidomic profiles will be reported.
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 5256.
Abstract 526: Tetraspanin CD81/TAPA-1 up-regulates MT1-MMP involved in melanoma cell motility through Akt-dependent Sp1 activation signaling pathways
Authors: Hong In-Kee , Wang Sun-Ju , Lee Moon-Sung , Park Iha , Kim Young-Myeong , Lee Hansoo 
Published: February 2011

Abstract
Tetraspanin CD81 is a member of transmembrane 4 superfamily proteins that have four putative membrane-spanning domains, short C- and N-terminal cytoplasmic domains, two extracellular loops and small intracellular loop. Tetraspanin CD81 is involved in cell adhesion, cell proliferation, motility and metastasis. In this study, to reveal the role of CD81 in tumor invasion, we examined the effect of CD81 overexpression on invasive phenotype in human melanoma cells. We also investigated the intracellular signaling pathways mediated by CD81 involved in these invasive phenotypes. For this study, we generated MelJuSo human melanoma cell lines stably expressing CD81. Cell invasion and motility of the CD81-transfected cells was enhanced significantly as compared to control transfectant cells lacking CD81 expression. In addition, MT1-MMP expression is up-regulated in CD81 transfectant cells as compared to control transfectant cells. MT1-MMP knockdown in CD81 transfectant cells abolished the increase of cell motility by CD81 expression, suggesting the role of MT1-MMP in CD81-induced cell motility. Through the studies using chemical inhibitors and siRNAs for gene knockdown, we found that Akt/PI3K signaling pathway is involved in CD81-mediated MT1-MMP expression. The enhancement of cell motility by CD81 expression was abolished by knockdown of Akt. Finally, we found the involvement of Sp1 transcription factor in the induction of MT1-MMP expression mediated by CD81. Sp1 binding site in MT1-MMP gene promoter was indispensable for the induction of MT1-MMP expression by CD81. Electrophoretic mobility shift assay confirmed the involvement of Sp1 in MT1-MMP expression by CD81. Taken together, these results suggest that tetraspanin CD81 stimulates melanoma cell invasion and motility by up-regulating MT1-MMP expression through the activation of AKT signaling pathways and Sp1 transcription factor.
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 526.
Abstract 5262: Resistance to fenretinide in neuroblastoma is associated with increased expression of sphingosine kinase and sphingosine-1-phosphate receptors and targeting sphingosine kinase reverses resistance
Authors: Ghent Matthew V. , Kim Youngleem , Jakimenko Ana , Reynolds C Patrick 
Published: February 2011

Abstract
The synthetic retinoid fenretinide, N-(4-hydroxyphenyl) retinamide (4-HPR), is selectively cytotoxic to cancer cells via increases in dihydroceramide levels and generation of reactive oxygen species and has clinical activity against recurrent neuroblastoma (J Clin Oncol 27: 15s abstr 10009, 2009). Metabolism of ceramides into various sphingolipid species, including sphingosine, and phosphorylation of dihydrosphingosine and sphingosine by sphingosine kinase 1 (SPHK1) are anti-apoptotic and thought to counter cytotoxicity mediated by ceramides. Multistep selection for resistance to 4-HPR was performed with a 4-HPR sensitive neuroblastoma cell line, SMS-KCNR (IC99=4.6 uM), resulting in the 4-HPR resistant line, KCNR-FR (IC99=19.9 uM). We generated a TaqMan low-density array (TLDA) that measures expression of 42 genes involved in ceramide synthesis and metabolism by quantitative RT-PCR. Genes overexpressed in KCNR-FR relative to SMS-KCNR included ceramide desaturase 2 (14.1-fold), sphingosine-1-phosphate receptors S1PR2, 3, and 4 (2.4, 1.6, and 1.3-fold, respectively), and SPHK1 (5.2-fold). These data point toward 4-HPR resistance being mediated by sphingosine-1-phosphate or dihydrosphingosine-1-phosphate, both of which are generated via phosphorylation of sphingosine by SPHK1. SPHK1-specific RNAi knockdown decreased SPHK1 mRNA expression (36% ± 0.007 of scrambled RNAi, p&lt;0.05) and significantly increased apoptosis (35.8 ± 1.7%; p&lt;0.05) in KCNR-FR treated with 4-HPR relative to scrambled RNAi controls (8.8 ± 6.5%; p&lt;0.05). Safingol (L-threo-dihydrosphingosine), a putative sphingosine kinase inhibitor in phase I trials, partially reversed KCNR-FR resistance to 4-HPR (Combination Index = 0.56). Thus, selection for resistance to 4-HPR in neuroblastoma was associated with increased expression of multiple components of the anti-apoptotic sphingosine kinase signaling pathway, and such resistance can be partially overcome by targeting sphingosine kinase.
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 5262.
Abstract 5264: Are the methylation of MGMT (O6-methylguanine-DNA methyltransferase) and the DNA mismatch repair (MMR) mechanism frequently involved in pediatric cancers?
Authors: Nguyen Aurelia , LEGRAIN Michele , Neuville Agnès , Pencreach Erwan , Guerin Eric , Lutz Patrick , Gaub Marie Pierre , Guenot Dominique , Entz-Werlé Natacha 
Published: February 2011

Abstract
In pediatric oncology more and more protocols are including now temozolomide (TMZ) as a drug in the first line treatment or at relapse time. MGMT activity is known to circumvent the toxicity of alkylating agents such as TMZ. The defect of MMR mechanism is involved also as a cellular way for cancers to resist to TMZ. Only few studies have been already done in the pediatric field focusing on the study of these markers of TMZ resistance. Based on the new therapeutic indications of this drug in pediatric cancers, we performed a study in 100 malignant pediatric tumors from various origins to evaluate the MGMT methylation and the MMR mechanism.
Material and methods: 12 high grade gliomas (HGG), 13 medulloblastomas (MB), 15 osteosarcomas (OS), 15 Ewing sarcomas (EWS), 15 rhabdomyosarcomas (RMS), 15 NBs and 15 acute lymphoblastic leukemias (ALLs) were included retrospectively in the study. DNA was extracted from tumors at diagnosis. In all tumors, the methylated status of MGMT was analyzed by methylation specific PCR (MS-PCR). Simultaneously, its expression was studied by immunohistochemistry. To analyze the MMR status in each tumor, an allelotyping method was performed in these tumors by using the NIH recommended microsatellites.
Results: Out of these 100 samples, 3 tumors (2 HGGs and 1 MB) were presenting a MSI (microsatellite instability), witness of a MMR deficiency. Only 5 tumors (2 EWSs, 2 HGGs and 1 MB) had a methylated MGMT promoter. One HGG was presenting both abnormalities at the same time. The immunohistochemical results were concordant with MS-PCR observations. Concerning the tumors treated with TMZ (12 HGGs, 4 MBs, 2 EWSs and 4 NBs), we do not observed any differences on survival between the unmethylated and methylated tumors.
Discussion: Methylation of MGMT promoter and MMR deficiency are rare in pediatric tumors and therefore seem not to be the major mechanisms involved in the sensitivity to TMZ. Our results suggest that in pediatric tumors, other mechanisms for TMZ sensitivity or resistance should be activated.
Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.
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 5264.