bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 132: Cytoprotective induction of nitric oxide synthase in a cellular model of 5-aminolevulinic acid-based photodynamic therapy
Authors: Bhowmick Reshma , Girotti Albert W. 
Published: February 2011

Abstract
Photodynamic therapy (PDT) employs a photosensitizing agent, molecular oxygen, and visible light to produce reactive oxygen species that kill tumor and tumor vasculature cells. Nitric oxide (NO) produced by these cells could be pro-carcinogenic by inhibiting apoptosis or promoting angiogenesis and tumor growth. Our previous studies showed that NO from a chemical donor made COH-BR1 breast tumor cells hyperresistant to apoptotic photokilling induced by photoactivation of 5-aminolevulinic acid (ALA)-generated protoporphyrin IX localized in mitochondria. Hyperresistance was associated with inhibition of proapoptotic JNK and p38α MAP kinase phosphorylation-activation. The purpose of this study was to determine whether tumor cells upregulate NOS-generated NO as a cytoprotective measure during PDT.COH-BR1 cells sensitized in mitochondria with ALA-derived protoporphyrin IX died apoptotically following irradiation as measured by Hoechst staining. Western analysis revealed that inducible nitric oxide synthase (iNOS) was upregulated &gt;3-fold within 4 h after ALA/light treatment, while other NOS isoforms were unaffected. Exposing cells to the iNOS inhibitor, 1400W during photochallenge enhanced caspase-3/7 activation and apoptotic killing up to 2-3-fold while substantially reducing chemiluminescence-assessed NO production, suggesting that this NO was cytoprotective. Consistently, the NO scavenger cPTIO enhanced ALA/light-induced caspase-3/7 activation and apoptotic kill by &gt;2.5-fold. Of added significance, cells could be rescued from 1400W-exacerbated apoptosis by an exogenous NO donor, spermine-NONOate. Using Hoechst and TUNEL staining, we found that short hairpin RNA (shRNA)-induced knockdown of iNOS enhanced the apoptotic kill of ALA/light treated COH-BR1 cells. ALA/light-treated COH-BR1cells exhibited a transient post-irradiation activation of JNK and p38α as measured by Western blot analysis. Consistently, both effects were intensified and prolonged by 1400W. The survival MAP kinase ERK1/2 was deactivated more rapidly when 1400W was present during a PpIX/light challenge. Similar effects on MAP kinase activation/deactivation were observed for iNOS knockdown cells under photostress cinfirming iNOS's protective role. As demonstrated for non-photodynamic stress systems, NO could have interfered with apoptosis by inactivating participating MAP kinases and/or caspases. This is the first reported evidence for increased tumor cell resistance due to iNOS upregulation in a PDT model. Our findings indicate that stress-elicited NO in PDT-treated tumors could compromise therapeutic efficacy, and suggest NOS-based pharmacologic interventions for preventing this. (Supported by NIH Grant CA70823)
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 132.
Abstract 1322: Sensitizing radiation-induced integrin β-1 signaling by targeting uPAR in medulloblastoma cells
Authors: Nalla Arun Kumar , Kotipatruni Rama Prasadarao , Ganji Purnachandra Nagaraju , Fassett Daniel , Klopfenstein Jeffrey D. , Dinh Dzung H. , Gujrati Meena , Rao Jasti S. 
Published: February 2011

Abstract
Although radiation is an effective therapy, it has several adverse effects, including the induction of secondary (new) tumor within the irradiated field. Several studies have reported this effect with medulloblastoma despite effective radiotherapy during the initial stages. Here, we attempt to capitalize on the radiation-induced aggressive behavior of medulloblastoma cells by examining migration, cell adhesion and matrigel invasion properties. Comparison at the mRNA levels between the matrigel-invading and non-invading cells (with and without radiation) clearly demonstrates the aggressiveness of irradiated medulloblastoma cells. RT-PCR analysis confirmed the increased expression of uPA, uPAR, focal adhesion kinase (FAK), N-Cadherin, and integrins like α3, α5, β1 and β6 in irradiated cells. Increased expression of uPAR and integrin β-1 in irradiated cells was also confirmed by immunofluorescence and immunoprecipitation assays. The interaction between uPAR and integrin β-1 and subsequent downstream signaling is a key process in malignant progression and metastasis and has been recently reported in mediating resistance to radiation. With this view, we aimed to study the effect of siRNA-mediated knockdown of uPAR on cell migration and adhesion in irradiated and non-irradiated medulloblastoma cells. Downregulation of uPAR not only reduced cell migration and adhesion, but also reduced the increased migration and adhesiveness associated with irradiated cells. Apart from specific knockdown of uPAR in siRNA-transfected cells, the increased expression of uPAR and integrin β-1 upon radiation were also reduced both at the transcript and protein levels. Studies of the uPAR/integrin β-1 downstream signaling cascade have shown that uPAR knockdown reduces both the expression and phosphorylation of FAK, paxillin, p130Cas and Rac-1, which are known to be actively involved in coordinating tyrosine kinase based signaling related to cell migration and adhesion. Our in vitro results demonstrate that targeting uPAR might sensitize the radiation-induced aggressiveness of medulloblastoma cells by affecting the uPAR/integrin β-1 signaling pathway.
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 1322.
Abstract 1324: Modulation of IR induced NFKB activity by manipulation of NOS coupling
Authors: Rabender Chris , Mikkelsen Ross 
Published: February 2011

Abstract
The transcriptional activity of NFκβ is in part regulated by nitric oxide (NO) and reactive nitrogen species (RNS). Previously we demonstrated that low doses of ionizing radiation (IR) activate constitutive, Ca2+ dependent NO Synthases (NOS) and the generation of RNS, resulting in protein Tyr nitration and/or Cys s-nitrosylation. Previous studies in our lab demonstrated that nitration of IκBα is critical for the IR-induced activation of NFκβ whereas others have shown that s-nitrosylation of the p65 subunit leads to the inhibition of NFκβ. Here we show that exposing MCF-7 cells to 5Gy IR results not only in Tyr nitration of IκBα but also Cys s-nitrosylation of NFκβ both with a maximum at 30min. post IR. One explanation for the discordant results is that NOS activity is uncoupled, resulting in the production of increased levels of superoxide anion as opposed to NO. Tetrahydrobiopterin (BH4) is a necessary cofactor that stabilizes the enzyme and allows the generation of NO through oxidation of L-arginine. However, if BH4 levels become limiting as found in chronic inflammatory or oxidative conditions, electron transfer is instead shuttled to molecular oxygen resulting in the production of superoxide anion, a scenario in which NOS is described as “uncoupled.” When NOS is uncoupled the resulting increase in superoxide can lead to enhanced levels of peroxynitrite formation, resulting in enhanced IκBα Tyr nitration and NFκβ activity. This evidence has led to the hypothesis that by altering cellular levels of BH4, the levels of Tyr nitration and Cys s-nitrosylation can be manipulated, leading to changes in NFκβ activity. To determine the effects of exogenous BH4 on IκBα nitration in MCF-7 cells, cells were treated with varying concentrations of cell permeable sepiapterin (SP), a precursor of BH4, and exposed to 5Gy IR. The results show that between 100nM-500nM IκBα nitration is all but completely eliminated, resulting in decreased NFκβ activity as assessed by luciferase assay. Initial experiments looking at the effects of SP on p65 s-nitrosylation have been variable. At a minimum, levels of s-nitrosylation remain the same as untreated cells; however, enhancement of s-nitrosylation is seen in some experiments. Studies are ongoing to clarify SP's effects on p65 s-nitrosylation as well as studies to determine SP's effects on tumor cell survival post IR.
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 1324.
Abstract 1332: Pediatric sarcomas are infiltrated with myeloid derived suppressive cells
Authors: Bouchkouj Najat , Qin Haiying , Galli Susana , Buckley John , Meadors Joanna L. , Larabee Shannon , Mackall Crystall L. , Tsokos Maria G. , Fry Terry J. 
Published: February 2011

Abstract
Introduction: Pediatric cancers have been reported to be infiltrated with macrophages. Tumor associated macrophages and myeloid derived suppressive cells (MDSCs) are increasingly recognized to play an important role in cancer immune escape, promote tumor progression by suppression of adaptive immunity, and are associated with poor prognosis in adult cancers. Little is known about the presence and the role of these cells in the pathobiology of pediatric cancers. We sought to analyze pediatric sarcomas for the presence of myeloid cells expressing inducible nitric oxide synthase (iNOS), arginase1 (Arg1), and/or indolamine 2,3 deoxygenase (IDO). Concomitantly, we used a murine model of embryonal rhabdomyosarcoma (ERMS) to further explore MDSCs associated with pediatric sarcomas.
Methods: We conducted immunohistochemical (IHC) studies on 20 paraffin embedded tumor samples of rhabdomyosarcoma, Ewing's sarcoma, desmoplastic small round cell tumor and malignant peripheral nerve sheath tumor, assessing for CD68, CD163, iNOS, Arg1 and IDO immunoreactivity. In the murine model, 1×106 RMS M3-9-M murine ERMS cells were injected intramuscularly into the gastrocnemius muscle of C57BL/6 mice. Tumors and spleens were excised on days 7, 12, 16 and 19 post injection and tumor and spleen myeloid cell were analyzed for CD11b, CD11c, Gr-1 and IL4R alpha expression and for gene expression of iNOS, Arg1 and IDO using RT-PCR.
Results: Pediatric sarcomas demonstrate significant macrophage infiltration with iNOS, Arg1 and IDO present in most of these samples. Murine ERMS also shows substantial numbers of MDSCs both in the tumor and spleen of tumor bearing mice, with increasing numbers as tumor burden increased. Comparisons between different myeloid cells subsets by relative quantitation of gene expression reveal the presence of an expanded population of cells that bear the hallmarks of MDSCs by expressing iNOS and Arg1. Significantly higher IDO expression was seen in MDSCs compared to other myeloid cells as tumors progressed.
Conclusion: Macrophages infiltrating pediatric sarcomas expressed markers associated with MDSCs, which have been shown to contribute to immune evasion and augment tumor growth in several other model systems. Similarly, murine ERMS M3-9-M induced accumulation of MDSCs in spleen and tumor microenvironment, with increasing numbers associated with tumor progression, suggesting that they may play an important role in growth of pediatric sarcomas. Immunomodulation of these cells might be a key step in enhancing the effectiveness of immune-based therapies.
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 1332.
Abstract 1334: Intratumoral soluble interleukin-6 receptor associated with disease progression in colorectal cancer
Authors: Okugawa Yoshinaga , Miki Chikao , Toiyama Yuji , Yasuda Hiromi , Yokoe Takeshi , Saigusa Susumu , Hiro Junichiro , Tanaka Koji , Inoue Yasuhiro , Nobori Tsutomu , Kusunoki Masato 
Published: February 2011

Abstract
Purpose. Interleukin-6 (IL-6) binds not only to membrane form but also to soluble IL-6 receptor (sIL-6R), derived from the extracellular part of the membrane receptor. Although most soluble receptors act as functional antagonists to their cytokine, sIL-6R plays a role in agonistic activity. The aim of this study was to clarify the relationship between concentration of intra-tumoral soluble interleukin-6 receptor levels and cancer progression in colorectal cancer patients, and to clarify its kinetics with clinical outcome.
Methods. We studied 161 patients undergoing surgery for colorectal cancer. We measured concentrations of sIL-6R in tumors and normal mucosa, and in supernatants from colonic cancer cell lines. Expressions of IL-6, membranous IL-6R and gp130 were evaluated by immunohistochemically
Results. The net balance between the concentration of sIL-6R in cancer tissue and normal mucosa (sIL-6R Ca/N expression ratio: the cancer tissue sIL-6R concentration divided by normal mucosa sIL-6Rntration) was 1.262 ± 1.156. The decreased sIL-6R Ca/N expression ratio was significantly associated with T classification (p=0.0076), distant metastasis (p=0.0102), UICC stage (p=0.0251) and poor prognosis (p=0.0003). In Cox multivariate analysis, distant metastasis and decreased sIL-6R Ca/N expression ratio were independent risk factors for poor prognosis. Colon cancer cell lines produced sIL-6R, and the production was exaggerated by IL-1beta stimulation, and was suppressed by the addition of IL-1 receptor antagonist. Immunohistochemically, IL-6, membranous IL-6R and gp130 were intensely expressed in cancer cell specifically, and IL-6 expression in cancer cytoplasm was associated with poor prognosis (p=0.0266). The decreased levels of sIL-6R Ca/N expression ratio in cancer tissue was inversely correlated with the intense IL-6 immunoreactivity in cancer cytoplasm (p=0.0088). Conclusion: Relative decrease in sIL-6R in the tumor stroma which reflects increased IL-6/sIL-6R affinity may play a key role in the progression of colorectal carcinoma via IL-6 tran-signaling.
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 1334.
Abstract 1335: Immune regulation in endometriosis and epithelial ovarian cancer
Authors: Mantia-Smaldone Gina M. , Budiu Raluca , Mansuria Suketu , Lee Ted , Zorn Kristin , Elishaev Esther , Edwards Robert P. , Vlad Anda 
Published: February 2011

Abstract
Objective: Examine the expression and immunogenicity of a known ovarian tumor-associated antigen, MUC1, in ectopic endometriosis lesions and epithelial ovarian cancer (EOC). Determine whether an imbalance in CD4 T cell subsets contributes towards endometriosis pathogenesis and ovarian carcinogenesis.
Methods: Biologic specimens were obtained from women with endometriosis, endometriosis-related (endometrioid and clear cell) or serous EOC, and healthy controls, according to University of Pittsburgh IRB protocols. MUC1 and immune cell expression were determined via immunohistochemistry (IHC). Anti-MUC1 IgM and IgG antibody levels were determined via ELISA. Peripheral blood mononuclear cells and cryopreserved cell suspensions from tissue lesions were immunophenotyped using multicolor flow cytometry. Stroma and epithelial cells from tissue biopsies were collected by laser capture microdissection (LCM) and examined with immune-based quantitative RT-PCR arrays.
Results: MUC1 was overexpressed in 67% of endometriosis and 89% of EOC lesions. Women with early or late stages of endometriosis had significantly higher anti-MUC1 IgM responses when compared to those women with endometriosis-related EOC (25.3 % of positive control vs.14.2%, p=0.03; 26.3 vs. 14.2%, p=0.04) and to those with serous EOC (25.3 vs. 14.6%, p=0.04; 26.3 vs.14.6%, p=0.04). Women without disease also had significantly higher anti-MUC1 IgM responses compared to endometriosis-related (29.2 vs.14.2%, p=0.01) and serous EOC (29.2 vs.14.6%, p=0.02). Immune cells, including CD3, CD4, and CD8 T cells, are present in endometriotic lesions and appear more abundant than in eutopic endometrium. Flow cytometric analysis of endometriotic lesion-infiltrating T cells revealed a decrease in the frequency of IFN-γ CD4 and CD8 T cells, similar to that seen in patients with EOC.
Conclusions: MUC1 is present and appears to be overexpressed in ectopic endometriotic and EOC lesions. Women with endometriosis-related EOC or with serous EOC had significant lower anti-MUC1 IgM levels, suggesting that a compression of antigen-specific humoral (i.e., Th2 driven) immunity may play a role in carcinogenesis. Endometriotic and EOC lesions also appear to have diminished Th1 immunity, suggesting a possible role for local immune suppression. Quantitative analyses of several immune genes in the lesion microenvironment are currently ongoing and will potentially contribute to immune biomarker discovery and improvements in the early detection and prevention of ovarian cancer.
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 1335.
Abstract 1340: High densities of tumor-infiltrating FOXP3+ regulatory T cells in primary tumor or lymph node metastasis are associated with favorable outcome in gastric cancer
Authors: Lee Hee Eun , Chae Seoung Wan , Lee You Jeong , Kim Min A , Lee Hye Seung , Lee Byung Lan , Kim Woo Ho 
Published: February 2011

Abstract
Background: It has been reported that the frequency of FOXP3+ regulatory T cells (Tregs) among tumor-infiltrating lymphocytes is increased in cancer-bearing patients. We designed the study to determine the prognostic significance of FOXP3+ Tregs in gastric cancer.
Methods: Tissue microarray and immunohistochemistry were used to assess the densities of FOXP3+ T regs in primary tumor tissue (n=216) and unmatched metastatic tumor tissue of regional lymph nodes (n=149) from gastric cancer patients. Numbers of FOXP3+ Tregs were counted using an image analysis program. FOXP3+ Treg densities were evaluated for correlation with clinicopathologic characteristics and overall survival.
Results: With respect to primary tumor, low density of FOXP3+ Tregs was associated with advanced T stage (p = 0.028), but not with any other clinicopathologic features. Kaplan-Meier survival analysis revealed that the high density group of FOXP3+ Tregs had longer survival time than the low density group (p = 0.001, log-rank test). In multivariate analysis, FOXP3+ Treg density remained an independent prognostic factor with hazard ratio (95% CI) of 0.651 (0.435-0.975). In addition, it was found that FOXP3+ Treg density in metastatic tumor of lymph nodes was an independent prognostic indicator, i.e., high density of FOXP3+ Tregs was significantly associated with improved survival (hazard ratio (95% CI) = 0.519 (0.318-0.848)).
Conclusions: FOXP3+ Treg densities in not only primary tumor, but also metastatic loci of regional lymph nodes were significantly associated with patient survival in gastric cancer. As our finding that high density of FOXP3+ Tregs was related to favorable prognosis contrasts with several previous studies, further investigation will be needed.
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 1340.
Abstract 1343: Toll-like Receptor 9 (TLR9) stimulation results in a change in tumor macrophage infiltration associated with an anti tumor effect in a mouse model of lung adenocarcinoma induced by oncogenic K-ras
Authors: Rabbe Nathalie , Belmont Laure , Yu Jing , Poulot Virginie , Gounant Valérie , Antoine Martine , Kurie Jonathan , Cadranel Jacques , Wislez Marie 
Published: February 2011

Abstract
Microenvironment and immune system contribute to tumor escape in cancer. Toll-like Receptor 9 (TLR9) stimulation with a CpG ODN (PF-3512676) was expected to restore antitumor response in a mouse model of lung adenocarcinoma (ADC) induced by oncogenic K-ras (K-rasLA1 mice). In these mice, TLR9 was not expressed by normal lung, nor tumor cells but only by the inflammatory tumor component as shown by TLR9 mRNA quantification by real time quantitative fluorescent PCR and immunohistochemistry. Sixteen week-old K-rasLA1 mice received PF-3512676 (n=13) or vehicle (n=13) through subcutaneous administration for 3 weeks. Mice were killed after completion of treatment. During autopsy procedure, lesions were counted on lung surfaces by investigators blinded to treatment group. Compared to the vehicle group, there was a decrease of tumor cell proliferation (PCNA staining score: 28.5% ± 1 vs 22.4% ± 0.8; p&lt;0.0001, respectively) and an increase of tumor cell apoptosis (CC3 western blot and staining score: 0.058% ± 0.01 vs 0.105% ± 0.01; p=0.0154, respectively) in the PF group. No effect was observed on the autopsy count (26.5 ± 3.7 tumors vs 24 ± 2.3; p=0.85) nor on the histological count (27 ± 3.4 tumors vs 20.7 ± 2.2; p=0.23). Macrophage infiltration studied by F4/80 staining was different between the two groups with a higher number of macrophages inside the tumors in PF group while a higher number in peritumor area in the vehicle group (intra/peritumoral macrophage ratio: 3.35 ± 0.5, PF group vs 1.68 ± 0.1 vehicle, p=0.003). LKR-13, a lung ADC cell line derived from K-rasLA1 mice, does not express TLR9 and was resistant to treatment with PF in vitro. However, LKR-13 cells grown as syngeneic tumors recruited macrophages, and those tumors regressed in response to treatment with PF. These findings provide evidence that TLR9 stimulation might reduced the expansion of lung ADC induced by oncogenic K-ras and suggest that phenotypic modification of macrophages may contribute to ADC regression.
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 1343.