bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract A22: Temozolomide upregulates B7-H1 in glioma cells and promotes immunoressistance against T cells
Authors: Irvin Dwain K. , Miyamoto Shinya , Black Keith , Rentsendorj Altanchimeg 
Published: January 2011

Abstract
Temozolomide is widely used as the first-line chemotherapeutic agent for malignant glioma. However, it can prolong the median survival and progression-free survival in glioblastoma patients by only a few months. Recently, it has been demonstrated that multiple human tumors express B7-H1 and B7-H4, immune inhibitory transmembrane glycoproteins, including glioblastoma. It has been suggested that tumor cells utilize these proteins as a potential mechanism of immunoressistance. Therefore, we sought to determine if glioma cells up-regulate B7-H1 and B7-H4 and promotes immunoressistance in glioma cells. We show by fluorescent activated cells sorting that T98G, human glioblastoma cell line, GBM157, GBM177, primary human glioblastoma cells, and GL26, murine glioma cell line, express both B7-H1 and B7-H4. We also demonstrate that both B7-H1 and B7-H4 were significantly up-regulated in surviving T98G, GBM157, and GL26 cells after 3-day temozolomide exposure. The standardized fluorescence index of B7-H1 protein after temozolomide (1000 mM) exposure significantly increased from 1.54 to 3.07 (p =0.0021) and that of B7-H4 significantly increased from 1.99 to 3.17 (p =0.0043) in surviving T98G cells. Real-time quantitative PCR also showed significant up-regulation in B7-H1 gene expression by 4.6 times (p &lt; 0.0001) and in B7-H4 gene expression by 2.0 times (p = 0.0398) after 3-day temozolomide (1000mM) exposure in surviving T98G cells. In order to determine if up-regulation of B7-H1 promoted immunoressistance we co-culture surviving temozolamide exposed glioma cells with either CD4+ or CD8+ T-cells and determined secreted levels of IL-10 by enzyme-linked immunofluorescence assay and T-cell apoptosis, respectively. We show that CD4+ T-cells significantly up-regulate IL-10 secretion after co-culture with surviving temozolamide exposed glioma cells and that CD8+ T-cells apoptosis is also significantly increased as compared to control GL26 glioma cells. Taken together, these results suggest that up-regulation of B7-H1 and B7-H4 in glioma cells promotes glioma immunoressistance through the up-regulation of CD4+ T-cell IL-10 secretion and CD8+ T-cell apoptosis.
Citation Information: Clin Cancer Res 2010;16(7 Suppl):A22
Abstract A24: Low mir-200c expression correlates with an aggressive, invasive, and chemoresistant phenotype of non-small cell lung cancer
Authors: Ceppi Paolo , Mudduluru Giridhar , Kumarswamy Regalla , Rapa Ida , Giorgio Scagliotti V. , Mauro Papotti , Heike Allgayer 
Published: January 2011

Abstract
The development of metastasis is the main reason for cancer-related death in non-small cell lung cancer (NSCLC). Initiation of metastasis involves an increase in cell motility mediated by the loss of cell-cell adhesion caused by E-cadherin repression, in a process commonly known as epithelial-to-mesenchymal transition (EMT). A central role for microRNA-200 family members in regulating EMT has been recently indicated, but data regarding the significance of their expression in lung tumors are still unavailable. The present study investigated the expression of mir-200c in a panel of NSCLC cell lines (n=9) and found a strong inverse correlation with cell invasive potential. Forced re-introduction of mir-200c into highly invasive/aggressive NSCLC cells induced a loss of mesenchymal phenotype, by restoring E-cadherin and reducing N-cadherin expression, and inhibited in vitro cell invasion as well as in vivo metastasis formation, as evaluated by chicken embryo metastasis assay. Moreover, mir-200c overexpression restored the sensitivity towards cisplatin and cetuximab, two chemotherapeutic agents widely used in the treatments of thoracic cancers, of the drug-resistant NCI-H1299 cells. Hyper-methylation of the promoter region was found to be the mechanism behind the loss of mir-200c in invasive cells, as evaluated by 5-aza-dC treatment and methylation specific PCR. In primary tumor specimens obtained from 45 consecutively resected NSCLC patients, mir-200c expression confirmed its role in malignant tumor progression, being significantly inversely associated with a poor grade of differentiation (p=0.01) and a higher propensity to lymph node metastases (p&lt;0.01). In conclusion, these data indicate that loss of miR-200c expression plays an important role in the initiation of an aggressive, invasive, and chemoresistant phenotype. The determination of its expression in tumors can be used for the stratification of the patients to be treated with anti-metastatic therapy.
Citation Information: Clin Cancer Res 2010;16(7 Suppl):A24
Abstract A28: The effects of combined treatment with NF-κB inhibitors and arsenic trioxide on leukemic cell lines
Authors: Stepnik Maciej , Smok-Pieniazek Anna , Komorowska Magdalena , Arkusz Joanna 
Published: January 2011

Abstract
Arsenic trioxide (ATO) induces growth inhibition and apoptosis in a wide variety of cancer cell lines. Some reports indicate that this effect can be enhanced by inhibiting the activity of transcription factor NF-κB.
The aim of our study was to evaluate the efficacy of combined treatment with ATO and selected NF-κB inhibitors (sulindac, parthenolide, BAY 11-7082, MG-132 and gliotoxin) in inducing cell death of five leukemic cell lines: EL-4 mouse thymoma, Jurkat, HL-60, K562 and HPB-ALL. The cytotoxicity of the chemicals was evaluated using 72-hrs WST-1 reduction assay and apoptosis was assessed with Annexin V-FITC/propidium iodide staining (FACS).
We observed that among the inhibitors tested, gliotoxin and MG-132 when used alone showed the highest cytotoxicity on all cell lines (effective concentrations less than 1 μM). Parthenolide and BAY11-7082 induced complete death of all cell lines at the concentration of 10 μM. All four inhibitors did not potentiated the effects of ATO used at 0.5 or 1 μM. Although sulindac was the least cytotoxic compound when used alone, it showed the highest potentiating effect on ATO induced cytotoxicity on all cell lines. The response of cells to the combination was rather diverse with Jurkat and HPB-ALL cells being the most sensitive. As a rule, all cell lines treated simultaneously with ATO (1 μM) and sulindac (100 μM) showed complete decrease in viability after 72 hrs. The results with annexin V/PI staining indicated apoptosis as the main cell death mechanism. This combination had much weaker effect on the viability of healthy blood lymphocytes.
The results of our study reveal an interesting cytotoxic effect of ATO with combination with sulindac on a panel of leukemic cell lines. The work was supported by the Polish State Committee for Scientific Research (grant No PB 2806/B/PO1/2007/33).
Citation Information: Clin Cancer Res 2010;16(7 Suppl):A28
Abstract A32: Pretargeted immunoPET of CEA-expressing in intraperitoneal human colonic tumor xenografts in nude mice
Authors: Schoffelen Rafke , Sharkey Robert M. , Franssen Gerben M. , Goldenberg David M. , McBride William J. , Rossi Edmund A. , Chang Chien-Hsing , Laverman Peter , Graaf Winette T.A. , Oyen Wim J.G. , Boerman Otto C. 
Published: January 2011

Abstract
Objective: Radiolabeled antibodies were being developed commercially for the detection of several cancer types. However, imaging with radiolabeled antibodies require a relatively long interval between injection and imaging acquisition for adequate contrast to develop. The pretargeting method is a 2-step method: a unlabeled bsMAb with affinity for the tumor and a small radiolabeled molecule is injected, followed by the a radiolabeled compound. This aims to optimize the imaging system by specific tumor accumulation and fast blood clearance of the radiopharmacon, which allows imaging within one hour. Short-lived positron emitting radionuclides, e.g. 68Ga (half life: 68 min) match the pharmacokinetics of the small molecule. In this study, pretargeted immunoPET with a bispecific monoclonal anti-carcinoembryonic antigen (CEA) x anti-histamine-succinyl-glycine (HSG) antibody, TF2, and a radiolabeled peptide, IMP288, was compared to 18F-FDG in detecting CEA-expressing tumors in nude mice.
Methods: Groups of five BALB/c nude mice were inoculated with CEA-expressing human colonic tumor cells intraperitoneally. One group received 5 MBq 18F-FDG intravenously (i.v.). Another group received TF2 and 5 MBq 68Ga-IMP288 i.v. 16 h later. After one hour PET/CT images were acquired. One day later this was repeated vice versa. Uptake of 68Ga-IMP288 or 18F-FDG in the tumors and other dissected tissues was determined.
Results: High, specific tumor uptake of 68Ga-IMP288 (23.4 ± 7.2% ID/g) was observed, with very low accretion in the normal tissues (intestines: 0.50 ± 0.19 % ID/g; liver: 1.83 ± 0.45 % ID/g). This resulted in high tumor-to-background ratios (e.g. tumor-to-intestines 57.5 ± 22.4) and in the clear visualization of the small intra-abdominal tumor lesions (1.5–5 mm), as soon as one hour after the injection of 68Ga-IMP288. 18F-FDG localized efficiently in the tumors (8.7 ± 3.1 % ID/g), but with physiological uptake in various normal tissues (intestines: 2.15 ± 0.61 % ID/g; liver: 2.78 ± 0.52 % ID/g). The low tumor-to-background ratio (e.g. tumor-to-intestines 4.0 ± 0.9) complicated the detection of the tumors.
Conclusions: This study indicated that pretargeted immunoPET with TF2 and 68Ga-IMP288 is a specific and sensitive method for detecting colon cancer.
Citation Information: Clin Cancer Res 2010;16(7 Suppl):A32
Abstract A37: Correlation of EGFR ligand expression with response to classical or targeted therapies in non-small cell lung cancer xenografts
Authors: Fichtner Iduna , Rolff Jana , Rivera Maria , Merk Johannes 
Published: January 2011

Abstract
Increased levels of the epidermal growth factor receptor (EGFR) and its cognate ligands are common in non-small cell lung cancer (NSCLC) and correlate with a poor prognosis. In the last years targeted therapies against the EGFR were developed, but results of clinical trials were rather disappointing. The identification of biomarkers in NSCLC as predictive factors for an individualized therapy is urgently needed.
Twenty six xenografts were established from fresh surgical material from NSCLC patients and characterized with regard to their sensitivity to four cytostatics (Carboplatin, Etoposide, Paclitaxel, Gemcitabine) and two EGFR-inhibitors (Cetuximab, Erlotinib). The expression of EGFR and its ligands epidermal growth factor (EGF), transforming growth factor alpha (TGFα), epiregulin and amphiregulin were examined at mRNA and protein level.
Three ligands, which bind exclusively to EGFR (EGF, TGFα and amphiregulin) showed correlations to the mRNA expression of the receptor. Also the mRNA-levels of amphiregulin and epiregulin correlated with each other. The responsiveness towards Etoposide correlated negatively with the EGF-protein (r=-0.479, P&lt;0.05) and with the EGFR-mRNA (r=-0.663, P&lt;0.01) expression. This could mean that the expression of the EGFR-pathway related molecules is able to protect tumor cells from the induction of apoptosis through a cytostatic drug. The response rate to Gemcitabine showed a negative correlation with the TGFα-mRNA level (r=-0.525, P&lt;0.01). Controversially, the amphiregulin-mRNA level correlated positively with the responsiveness to Gemcitabine (r=0.553, P&lt;0.01). A high level of TGFα-mRNA correlated with the resistance to Erlotinib (r=-0.456, P&lt;0.05). The epiregulin-mRNA level showed a positive correlation concerning the sensitivity towards Cetuximab (r=0.476, P&lt;0.05). High EGFR levels seem to be indicative for the resistance to Erlotinib (r=0.636, P&lt;0.05) in squamous cell carcinomas and for the sensitivity to Cetuximab (r=-0.888, P&lt;0.05) in adenocarcinomas.
The results of the present study showed the role of the EGFR activated pathways in the dynamics of tumor progression in NSCLC on the one hand and reflect the high level of redundancy and interrelationships of the EGFR signalling pathway on the other hand. The patient-derived NSCLC models are suitable tools for the identification of biomarkers and their regulation mechanisms in a clinically related and standardized way.
Citation Information: Clin Cancer Res 2010;16(7 Suppl):A37
Abstract A39: A newly defined role of clusterin in the formation of exosomes derived from prostate cancer cells
Authors: Hosseini-Beheshti Elham , Zoubeidi Amina , Nip Ka Mun , Gleave Martin E. , Guns Emma S. 
Published: January 2011

Abstract
Introduction: Molecular chaperones, including heat-shock proteins (Hsps), help cells cope with stress-induced protein misfolding and aggregation and play prominent roles in cellular signaling and transcriptional regulatory networks asscociated with cancer progression and treatment resistance. Clusterin (CLU) is a stress-activated cytoprotective chaperone, up-regulated in Castration Resistant Prostate Cancer (CPRC), that confers hormone and chemo-resistance. Targeting inhibition of CLU using OGX-011 enhances treatment-induced cell death therapeutic response as is currently in clinical trials of men with advanced prostate cancer. Recent studies have linked cancer with exosome formation; exosomes are 30–100 nm membrane-bound compartments secreted from normal and tumor cells. The mechanisms underlying exosome formation and secretion are not fully understood. Factors such as stage of cancer, cell type and cell cycle could affect the amount and composition of exosomes formed and secreted. Since CLU has chaperone activity with a potent ability to inhibit amorphous and fibrillar aggregation of many different proteins, we hypothesize that it can influence exosome formation and release from androgen independent PCa cells.
Methods-Results: PC3 cells were seeded and grown in DMEM with 5% FBS until 70% confluency. Media was changed to 5% charcoal strip serum DMEM and finally to a serum free media for 72 hours before exosome isolation. Exosomes were purified from the conditioned media using differential centrifugation after remove cell debris and protein aggregates. Further analysis by transmission electron microscopy detected the integrity of purified exosomes and their concentration. Western blot analysis was also used to probe for different exosome markers including Actin, Tubulin, TSG 101, HSP70 and CD36. In this study, we functionally analyzed the role of Clusterin in relation to exosome formation from PC-3 PCa cells. Clusterin was knocked down in PC3 cells using siRNA, and confirmed with western blot analysis. The content of Clusterin in exosomes after knockdown remains unchanged while, in contrast, cells become Clusterin depleted. Upon Clusterin knockdown in PC3 cells we also observe a dramatic reduction in the amount of exosomes formed.
Conclusion: We have found high levels of CLU in exosomes derived from PCa cells. Our data suggests that CLU may serve a role in exosome formation since knocking it down by siRNA dramatically inhibits the quantity of exosomes formed.
Citation Information: Clin Cancer Res 2010;16(7 Suppl):A39
Abstract A40: The incorporation of PTEN/EGFR (DNA) FISH and quantitative biomarker immunofluorescence identifies a phenotype associated with survival in patients with malignant glioma
Authors: Donovan Michael Joseph , Erill Nadina , Puig Pere , Colomer Anna , Boluda Susana , Ferrer Isidre 
Published: January 2011

Abstract
Introduction: Glioblastoma multiforme (GBM) is the most common and malignant of adult glial tumors. Despite best standard of care including surgical resection, radiation and chemotherapy (e.g. temozolomide), the median survival remains approximately 12 – 15 months, with fewer than 25% of patients surviving up to 2 years and less than 10% of patients surviving up to 5 years. We sought to identify a preliminary set of baseline tissue-based DNA and protein features which may reflect growth mechanisms responsible for disease progression, and overall survival (OS).
Methods: Formalin fixed paraffin embedded specimens from 54 patients (44 Astrocytoma (including 14 GBM), 6 oligodendroglioma and 4 mixed) with outcome data and a median follow-up of 3 years were evaluated using dual-color DNA FISH for PTEN and EGFR. A multispectral immunofluorescent (IF) assay was used as previously described (Cordon-Cardo et al., 2007) to evaluate Ki67, PTEN, and P-AKT. Feature performance was univariately assessed using Kaplan-Meier survival curves.
Results: A &gt;10% Loss of heterozygosity (LOH) for PTEN (p-value &lt;0.05) but not EGFR amplification / polysomy was associated with decreased OS in the total cohort. By comparison, the combination of PTEN LOH and EGFR amplification/polysomy in the GBM-only group (n=12, complete data files) was associated with improved survival (p-value 0.03). By quantitative IF, increasing levels of KI67 were associated with shortened OS (p-value 0.004) in the total cohort.
Conclusions: The incorporation of DNA FISH and quantitative IF is useful for developing a biologic baseline for understanding disease course in malignant gliomas. PTEN LOH and EGFR amplification / polysomy in GBM may suggest a pathway mechanism for favorable response.
Citation Information: Clin Cancer Res 2010;16(7 Suppl):A40
Abstract A9: Preclinical modeling of responses and resistance of residual metastatic disease to adjuvant chemotherapy
Authors: Day Chi-Ping , Carter John , Bonomi Carrie , Hollingshead Melinda , Merlino Glenn 
Published: January 2011

Abstract
The questionable predictive power of available preclinical models is explained in part by their failure to adequately replicate the clinical setting. Prevailing human xenograft models do not consider advanced disease, require the use of immunocompromised mice that reconstitute aberrant tumor-host interactions, and employ delayed tumor growth as an endpoint, which has limited clinical relevance. To overcome these deficiencies, we have developed a rapid preclinical model of spontaneous metastasis that more accurately recapitulates clinical procedures for advanced non-small cell lung cancer patients. Lewis Lung Carcinoma tumor tissue that was never adapted to cell culture was stably labeled using lentivirus-encoding bioimaging markers, inoculated into syngeneic C57BL/6 mice, and resected upon reaching a predetermined size. Mice were then treated in a setting akin to post-surgical, first-line adjuvant chemotherapy using cisplatin, paclitaxel and/or antiangiogenic agents. As in the clinic, these drugs were most effective against progression in combination. However, the response of metastases to agents could not be predicted from, and often opposed, their effects on subcutaneous tumors. Time to macrometastatic onset, instead of growth, correlated with mouse survival. Moreover, the most effective adjuvant chemotherapy did not inhibit growth, but rather extended the equivalent of clinical dormancy. These results indicate that metastatic disease is driven by micrometastatic to macrometastatic transition, and resistance to therapies is caused by the failure to maintain clinical dormancy. Identification of the mechanisms involved in these processes will provide new targets of anti-cancer therapies and biomarkers for monitoring therapeutic efficacy. We demonstrate the inadequacies of current preclinical models, and introduce a paradigm for a more clinically relevant model that may more accurately predict therapeutic response in late-stage cancer patients.
Citation Information: Clin Cancer Res 2010;16(7 Suppl):A9
Abstract B12: A novel gene signature associated with response to adoptively transferred T cells in a mouse model of breast cancer
Authors: Martin Michele L. , Chun Hye-Jung Elizabeth , Hsu Janine , Ou David , Jones Steven M. , Watson Peter , Nelson Brad H. 
Published: January 2011

Abstract
Introduction: Adoptive T cell therapy involves the infusion of large numbers of activated, tumor-reactive T cells. In clinical trials, this method often results in mixed responses, wherein some tumor nodules respond while others do not, indicating that the local tumor environment is a critical determinant of response.
Aim: We sought to identify a gene expression signature associated with sensitivity of mammary tumors to adoptive T cell therapy in a mouse model of breast cancer.
Materials and Methods: A transgenic mouse model was used to derive a panel of mammary tumor lines expressing an ovalbumin-tagged version of the HER-2/neu oncogene. Within the panel were tumor lines that reproducibly underwent complete regression (CR), partial regression (PR), or progressive disease (PD) after adoptive transfer of naive, ovalbumin-specific CD4+ (OT-II) and CD8+ (OT-I) T cells. Six representative tumors representing three outcome groups (CR, PR, and PD) underwent Affymetrix gene expression profiling, and results were validated by quantitative PCR.
Results: Gene expression profiling identified four biological pathways associated with outcome following adoptive immunotherapy: leukocyte extravasation, extracellular matrix receptor, GM-CSF receptor, and LXR/RXR receptor pathways. From these pathways, 32 genes that ranked highest for discriminating CR and PD were chosen for further study. The tight junction protein Claudin 4 was expressed at high levels in PD tumors, intermediate levels in PR tumors, and low levels in CR tumors. By contrast, expression levels of the secreted extracellular matrix protein Reelin and the pro-inflammatory cytokine IL-18 were higher in CR tumors compared to PR and PD tumors.
Conclusions: Pathways related to cell junctions, extracellular matrix and inflammation influence the response of mammary tumors to adoptively transferred T cells. Currently, we are modulating expression of these and other genes in mammary tumors to identify regulatory nodes that determine outcome and are amenable to therapeutic intervention. Funding: Canadian Institutes for Health Research, Michael Smith Foundation, BC Cancer Foundation
Citation Information: Clin Cancer Res 2010;16(7 Suppl):B12