bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 5358: Comparison of tumor-forming ability in different fractions of pancreatic ductal adenocarcinoma cells
Authors: Hagio Masahito , Matsuda Yoko , Kawamoto Yoko , Yanagisawa Yuji , Makino Hiroshi , Naito Zenya , Ishiwata Toshiyuki 
Published: August 2012

Abstract
Introduction: Pancreatic ductal adenocarcinoma (PDAC) is associated with a high mortality rate due to its aggressive growth and high metastatic rate. Recently, cancer stem cells have been reported to play a central role in the proliferation, metastasis, and drug resistance of cancer. Although cancer stem cell-like cells seem to be included very loosely in cancer cells, information is still limited. Furthermore, the appropriate way of detecting cancer stem cells has remained controversial. In the present study, we tried to detect and collect a side population (SP) fraction as pancreatic cancer stem cells using Hoechst staining, and compared the in vivo tumor-forming abilities between the major population (MP) and SP of PDAC cells. Methods: A human pancreatic cancer cell line, KLM-1, was stained with Hoechst 33342. We distinguished between MP and SP of cells by the positivity of Hoechst, and then each fraction was isolated using a flow cytometer. Different numbers (1.0×102, 103, 104, and 105) and fractions (MP and SP) of cells were subcutaneously injected into the left and right sides of the back of NOD.CB17-Prkdcscid/J (NOD/SCID) mice. During a 5-week test period, the tumor size was measured regularly. Results: After 5 weeks, tumors were formed in mice injected with above 1.0×104 cells of both fractions. Especially, with the injection of 1.0×105 cells, the tumor-forming rate was 100% in the SP group, whereas it was 66.7% in the MP group. Furthermore, tumors were generated at about 1 week after the injection of the SP fraction (1.0×105 cells); however, in the MP group, it took about 3 weeks to generate a tumor after the injection of the same number of cells. Totally, the tumor volumes of the SP group were bigger than those of the MP group. Even with the injection of 1.0×104 cells of the SP fraction, the tumor volume was bigger than that on the injection of 1.0×105 cells of the MP fraction. Subcutaneous tumor tissues derived from SP and MP cells showed similar histological features. Conclusion: The malignancy of the SP fraction in PDAC cells was confirmed. This fraction might include cancer stem like-cell properties, and may be a candidate for therapeutic target in malignant PDAC.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5358. doi:1538-7445.AM2012-5358
Abstract 5359: Gene expression characterization of different cancer stem cell isolation methods in head and neck cancer
Authors: Thibodeau Bryan , Geddes Timothy , Galoforo Sandra , Akervall Jan , Wilson George 
Published: August 2012

Abstract
Background: Head and neck squamous cell cancer (HNSCC) is a heterogeneous cancer that continues to pose major clinical problems. There is growing evidence that cancer stem cells (CSCs) may be an important factor in disease progression and resistance to current treatments. Establishing that stem cells are present in HNSCC and characterizing their global gene expression patterns provides the rationale for this study. Methods: A series of 5 HNSCC cell lines that have been maintained at low passage number such that they maintain phenotypic and morphological characteristics similar to the primary tumor were used in this study. Three different strategies were used to isolate stem cells by flow cytometry sorting: 1) Hoechst 33342 “side” population, 2) Aldefluor, and 3) CD44 bright cells. Global gene expression for each isolated CSC-enriched population and its associated CSC-depleted population was analyzed using Affymetrix Human Exon 1.0ST arrays. Gene set enrichment analysis was performed using Ariadne Pathway Studio. Results: The different methods of identifying CSCs produced widely different populations. In side population cells, there were 77 differentially expressed genes (p&lt;0.05 and 1.5-fold cutoff) while only 59 and 17 genes were differentially expressed in the CD44 bright and Aldefluor bright populations, respectively. Not a single gene was commonly altered between any two of the isolation methods. Gene set enrichment analysis, however, was able to identify categories that differed between the CSC-enriched and CSC-depleted populations. Biological processes of cell cycle, cell division, mitosis, translational elongation, and spindle assembly were highly regulated. Microtubule binding/microtubule plus-end binding and structural constituent of ribosome were commonly altered molecular functions. Conclusions: This study suggests that current methods for isolating putative stem cells in HNSCC result in diverse populations with differing expression of specific genes. However, when examined for global expression patterns, several important categories of genes are commonly altered between the CSC-enriched and CSC-depleted populations. Some of the known characteristics of stem cells such as asymmetric division and unlimited growth potential are suggested by the highly regulated categories of cell division and spindle assembly. From these studies we hope to gain greater insight into the importance of stem cells in HNSCC as well as improve the capability of identifying these potentially important new targets for treatment.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5359. doi:1538-7445.AM2012-5359
Abstract 5362: Multidrug-resistance (MDR-1) gene expression in immature glioma cells
Authors: Shimizu Keiji , Ishida Eri , Higashi Yoichiro , Fujimoto Yasunori , Yawata Toshio 
Published: August 2012

Abstract
Cancer stem cell hypothesis suggests that small populations of stem-like cells exist in the tumor mass and harbor drug resistance and low radio-sensitivity, and thus resulting in tumor recurrence after various treatments. In this study, we investigated the relationship between cell differentiation and drug resistant gene expression in glioblastoma. Glioma stem-like cells freshly isolated from surgical specimens were enriched in tumor sphere (TS) culture and were more resistant to anti-cancer drugs compared with their differentiated cells in cell viability assay. These cells were also tested for phosphorylation of histone H2AX at Ser139, a biomarker of DNA lesions including DNA double-strand and single-strand breaks. Differentiated cells were much more susceptible to anti-cancer drug-induced DNA damage, compared with TS cells. The expression of drug resistance genes, MDR-1, MRP-1 and MRP-2 in TS cells was more than those in their differentiated cells by RT-PCR analysis. However, there was no correlation between drug resistance genes and stem cell marker CD133 expression. It is possibly caused by another cell population expressing drug resistance genes, therefore, we sought to define the existence of progenitor cells in glioma by detection of glial progenitor marker, A2B5 using flow cytometric analysis. CD133 and A2B5 positive cells were more abundant in TS cells and were decreased during induction of differentiation. The expression of MDR-1 was frequently observed in CD133+/A2B5−, CD133+/A2B5+ and CD133−/A2B5+ cells. Reduction of MDR-1 expression concomitantly occurred with the differentiation of these immature glioma cells. Thus, it is revealed that CD133 negative cells expressing MDR-1 are A2B5-positive glioma cells. These results suggest that drug resistance genes are expressed not only in tumor stem cells but also in progenitor cells.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5362. doi:1538-7445.AM2012-5362
Abstract 5363: Aggregation rather than monoclonal expansion explains ovarian cancer spheroid formation
Authors: Huang Zhiqing , Lowery William J. , Berchuck Andrew , Murphy Susan K. 
Published: August 2012

Abstract
Purpose: It is thought that a subpopulation of ovarian cancer cells possess stem cell like properties and are responsible for both the emergence of cancer and for subsequent chemoresistance and recurrence. A common approach used to enrich for cancer stems cells in vitro involves culture in selective media on low attachment plates resulting in non-attached multicellular spheres. Spheroids are present in ascites fluid of women with ovarian cancer, and may contain stem cells responsible for metastasis and recurrence. Our objective was to address whether spheroids are truly monoclonal in origin and arise from expansion of a single common progenitor cell. Procedures: We cultivated 5 ovarian cancer cell lines (DOV13, HEYC2, OVCAR2, OVCAR3, and PEO4) to confluence in monolayer cultures. The cell lines were chosen for their ability to form spheroids as well as variation in expression of the stem cell marker CD133 (OVCAR2, OVCAR3 CD133+, others negative). The cells were trypsinized to form single cell suspensions and plated at densities ranging from 100 to 5000 cells per plate in stem cell-selective media in ultra-low attachment culture dishes. A Zeiss Axio Observer microscope was used for time-lapse photography of the plated cells at 5-minute intervals over a 24-hour period. In addition, single cell suspensions were subjected to flow activated cell sorting to plate one cell in each well of 96-well Costar ultra-low cluster plates to monitor clonal formation of spheroids. Results: Cells were dissociated and plated under stem cell-selective conditions and 288 images of each cell line were recorded over 24 hours. The cells were found to begin to aggregate within two to four hours, regardless of cell numbers plated. By 24 hours post-plating, there was pronounced aggregation in 5/5 (100%) cell lines with formation of tightly compacted spheroid structures in 4/5 (80%) cell lines. Single cells in the 96-well plates showed no evidence of spheroid formation over a 14-day observation period. Conclusion: We observed spheroid formation in both CD133 positive and negative ovarian cancer cell lines. Formation occured due to cellular aggregation rather than clonal expansion from a single progenitor with stem cell properties. Although cellular aggregation may be relevant to ovarian cancer biology, these data suggest that spheroid formation should be viewed with caution if used as a proxy for monoclonal expansion of ovarian cancer stem cells.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5363. doi:1538-7445.AM2012-5363
Abstract 5372: Dendritic-cell based vaccine for advanced pancreatic cancer: A report of 39 cases treated in Seren Clinic Nagoya
Authors: Kobayashi Masanori , Sakabe Tomoyo , Kure Shigehiro , Okamoto Masato , Yokokawa Kiyoshi 
Published: August 2012

Abstract
Objective: In the current study, we retrospectively assessed the efficacy of dendritic cell (DC)-based vaccine in advanced pancreatic carcinoma (PC). Patients: From Jan 2009 to April 2010, 39 patients (19 males and 20 females; aged 32-78 years, median 64 years) with advanced PC were treated with DC-based vaccine, and 38 patients also received GEM and/or S-1. Methods: Patient-derived peripheral blood mononuclear cells were obtained by leukapheresis (400ml×13 cycles), then adherent cells were cultured with GM-CSF, IL-4, OK-432 and PGE2 to generate DCs. The DCs pulsed with tumor specific peptides (WT1/MUC1) were injected at 2-week intervals (mean=8.3, max= 16 vaccinations). Results: The mean observation period was 257.6 days. None of the 39 patients showed CR, but we have found out 9 cases of PR and 9 cases of SD in accordance with RECIST. Response rate was 55% in the patients in combination with S-1+GEM and 9% with GEM alone. Disease control rate was 77.8% with S-1+GEM and 38% with GEM alone. Conclusions: DC-based vaccination in combined with GEM/S-1 was shown to be safe and possibly effective in patients with advanced pancreatic cancer.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5372. doi:1538-7445.AM2012-5372
Abstract 5400: Investigating the role of IDO in MUC1 expressing breast cancers
Authors: Besmer Dahlia , Kidiyoor Amritha , Nath Sritama , Roy Lopamudra Das , Curry Jennifer , Mukherjee Pinku 
Published: August 2012

Abstract
Breast cancer is the second most common cancer in the U.S. and contributes to 40,000 deaths a year. Breast cancer vaccines are currently being considered as a clinical intervention that may reduce the chance of metastasis and recurrence, and perhaps even function to be effective in cancer prevention. MUC1, a membrane tethered mucin glycoprotein, is over expressed in &gt;90% of breast cancers, and therefore has been recently described as the second most targetable tumor antigen by the National Cancer Institute. There are currently ongoing trials using the MUC1 vaccine in patients with metastatic breast cancer. However, immunotherapy has had limited success because tumors have the ability to undergo immune evasion tactics. This includes expression of Indoleamine 2,3-dioxygenase (IDO) immunosuppressive enzymes. IDO was first identified in maintaining maternal tolerance towards the antigenically foreign fetus during pregnancy. Its activity is increased under pathological conditions, including during tumor development. IDO is emerging as a key player in T cell suppression and in the induction of immune tolerance to tumors. The present study is focused on understanding the role of IDO enzymatic activity on tumor development and immune function. In this study, we injected two cell lines that express IDO, and one cell line that is IDO null (MTAG, MTAG.MUC1 and IKOM, respectively). These cell lines were injected into either IDO null mice, or control c57/bk6 mice (n=3 each). We hypothesized that IDO expression in the tumor microenvironment of mice creates a pathological state of immune suppression resulting in altered tumor progression and immune function. We show that mice (whether they be IDO null or blk6) injected with IKOM cells have significantly slower tumor progression and rates of secondary metastasis as compared to those injected with IDO expressing tumor cells (p&lt;0.05). In vitro, IKOM cells had significantly lower proliferative rates than the IDO expressing cells. Furthermore, mice injected with IKOM cells had a greater percentage of CD4+ and CD8+ T cells as compared to those mice injected with IDO expressing tumor cells. Mice injected with IDO expressing cells had a greater percentage of MDSC's characterized by the expression of gr1 and cd11b. Future studies would investigate the role of MUC1 based vaccines in combination with an IDO inhibitor, with the goal of reducing metastasis and increasing survival in patients with breast cancer.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5400. doi:1538-7445.AM2012-5400
Abstract 5405: Immuno-phenotyping reveals cell types present in circulation of breast cancer patients and elucidates their funstional potential
Authors: Ramirez Oscar 
Published: August 2012

Abstract
Myeloid derived suppressor cells (MDSC) have an identified role in suppressing anti-tumor immunity through Jak/Stat pathway activation and the generation of reactive oxygen species and arginase -1, thus promoting cancer progression. There is robust data on the identification of functionally suppressive MDSCs in preclinical models. However, such knowledge is underdeveloped in human cancers. Specifically, the clear identification of the true MDSC and their role in tumor immunoevasion, cancer progression and metastasis is undefined. Therefore, comprehensive identification of MDSCs and their ability to augment tumor-induced immune suppression in newly diagnosed early stage breast cancer is warranted to define their potential as a novel immunotherapeutic target. To delineate the role of MDSCs in newly diagnosed, untreated breast cancer and their tumor immunosuppressive effects in comparison to normal hosts, we conducted a prospective trial of stage I-IV breast cancer patients enrolled prior to initiation of systemic therapy and their age-matched normal donors. The following immune cell subsets were analyzed: regulatory T cells (CD3+/CD4+/CD25+/Foxp3+), MDSCs (Linlo/HLA-DR-/CD33+/CD11b+), and DCs (Lin-/CD14-CD4+/CD303+/CD1c+/CD141+). Functional assays of T cell activation and MDSCs mediated-T cell suppression were performed. We identified no significant differences in the percentage of regulatory T cells or mDC2 between breast cancer subjects and normal controls. In contrast, the percent of MDSC, pDCs and conventional DCs detected were suprisingly significantly higher in the healthy donor population as compared to breast cancer subjects. Breast cancer T cells showed reduced capability to respond to external stimulus as measured by up-regulation of CD25 and CD69 as well as T cell proliferation, although not statistically significant relative to normal controls. Breast cancer MDSC were significantly more suppressive of T cell activation relative to normal controls. The granulocytic but not monocyte subset of MDSCs (distinguished by CD15 expression) were identified as the main responders to PMA stimulation. Our results demonstrate immune suppression in newly diagnosed invasive breast cancer is characterized by increased immune suppressive function of MDSCs in the absence of increased cellular levels. When we looked at our cases with the highest MDSC levels, no distinct trend towards advanced stage or poorer prognosis biologic subtype was identified. These data support the identification of MDSCs in breast cancer as a novel therapeutic target to improve treatment outcomes.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5405. doi:1538-7445.AM2012-5405
Abstract 5407: The upregulation of BTLA and PD-1 defines a novel subset of dysfunctional tumor antigen-specific CD8+ T cells
Authors: Fourcade Julien , Sun Zhaojun , Pagliano Ornella , Guillaume Philippe , Luescher Immanuel F. , Sander Cindy , Kirkwood John M. , Olive Daniel , Kuchroo Vijay , Zarour Hassane M. 
Published: August 2012

Abstract
Cytotoxic T cells present at the periphery or at tumor sites recognize tumor epitopes presented by melanoma cells but fail to induce tumor rejection in melanoma patients. Inhibitory receptors including PD-1 and Tim-3 expressed by spontaneous CD8+ T cells directed against the cancer-germline antigen NY-ESO-1 play a role in promoting tumor-induced T cell dysfunction. In the present study, we show that BTLA is upregulated on spontaneous NY-ESO-1-specific CD8+ T cells and that BTLA+PD-1+Tim-3− CD8+ T cells represent the largest subset of NY-ESO-1-specific CD8+ T cells in melanoma patients. BTLA+PD-1+Tim-3− CD8+ T cells are partially dysfunctional, producing less IFN-γ than BTLA−PD-1+Tim-3− and BTLA−PD-1−Tim-3− but more IFN-γ, TNF and IL-2 than highly dysfunctional BTLA+PD-1+Tim-3+ NY-ESO-1-specific CD8+ T cells. Unlike PD-1, BTLA expression by NY-ESO-1-specific CD8+ T cells does not increase with higher T cell dysfunction or upon cognate antigen stimulation, suggesting that BTLA upregulation occurs independently of functional exhaustion driven by high antigen load. Finally, BTLA pathway blockade adds to PD-1 and Tim-3 blockades, enhancing NY-ESO-1-specific CD8+ T cell expansion, proliferation and cytokine production. Collectively, our findings support the targeting of BTLA, PD-1 and Tim-3 pathways to reverse tumor-induced T cell dysfunction in patients with advanced melanoma. This work was supported by the National Institutes of Health/National Cancer Institute grants R01CA90360 and R01CA157467 (to H.M. Zarour), an award from the Melanoma Skin Spore grant NCI P50CA121973 (to H.M. Zarour) and a grant from the Cancer Research Institute (to H.M. Zarour).
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5407. doi:1538-7445.AM2012-5407
Abstract 5408: CD73 as a target in cancer immunotherapy
Authors: Smyth Mark J. , Beavis Paul , Darcy Phil K. , Loi Sherene , Stagg John 
Published: August 2012

Abstract
It is increasingly being recognised that the tumor microenvironment modulates the effector functions of tumor-infiltrating lymphocytes and consequently suppresses anti-tumor immunity. One immunosuppressive component of the tumor microenvironment is elevated levels of adenosine. The conversion of ATP into adenosine occurs in a stepwise manner essentially through the enzymatic activity of CD39 (NTPDase I) (ATP&gt;AMP) and CD73 (ecto-5′-nucleotidase- AMP&gt;adenosine). CD73 is a glycosylphosphatidyl-inositol (GPI)-linked cell surface enzyme constitutively expressed on endothelial cells, foxp3+ Tregs and subsets of leukocytes, and is considered as the rate-limiting enzyme in the production of extracellular adenosine. We have recently demonstrated that one of the mechanisms contributing to the immunosuppressive accumulation of extracellular adenosine in tumors is the expression of CD73 by tumor cells, but CD73 expression on foxp3+ Tregs is also important for their suppression of anti-tumor immunity. We now report on the role of host-derived CD73 in de novo tumor development in mice. Combinations of anti-CD73 with agonist and T cell checkpoint blockade antibodies demonstrate significant beneficial effects in experimental and de novo models of tumorigenesis. In humans using large cohorts we have shown that CD73 is highest in triple negative breast cancer (TNBC) and expression correlates with an invasion marker and the lack of ER signalling. CD73 expression is also associated with a worse prognosis in TNBC irrespective of treatment and predicts response to anthracycline therapy. The development of CD73 as a target for cancer immunotherapy will be further discussed.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5408. doi:1538-7445.AM2012-5408