bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2892: Glycogen synthase kinase-3α regulates cell proliferation in pancreatic cancer cells by regulating constitutive TAK1 and NF-κB signaling
Authors: Bang Deepali , Wilson Willie , Yeh Jen Jen , Baldwin Albert S. 
Published: June 2012

Abstract
Pancreatic ductal adenocarinoma (PDA) represents the fourth leading cause of cancer-related deaths in the United States with a 5-year patient survival rate less than 5%. The transcription factor NF-κB is constitutively active and contributes to cell survival and cancer therapy resistance in these tumors. Previous reports have linked constitutive IκB kinase (IKK) activity to canonical NF-κB signaling in human pancreatic cancer cells. However, the signaling events that drive IKK activity remain poorly understood. TGF-β activated kinase 1 (TAK1) is an established regulator of IKK activity and has been shown to be active in human cancer cell lines. Moreover, we previously reported that glycogen synthase kinase-3 (GSK-3) signals through IκB kinase (IKK) to facilitate downstream pro-survival NF-κB signaling and inhibition of GSK-3 suppressed cell proliferation in pancreatic cancer cells. Here, we investigate the status of TAK1 activity in pancreatic cancer cells and explore the potential regulation of constitutive TAK1-IKK signaling by GSK-3.
We observed elevated levels of TAK1 phosphorylation and its association with TAB1 in a panel of pancreatic cancer cell lines. Genetic ablation of TAK1 in Panc-1 and MiaPaCa-2 cell lines resulted in decreased pro-survival NF-κB signaling. TAK1 was found to interact with GSK-3α in co-immunoprecipitation studies and both the genetic ablation and inhibition of GSK-3α suppressed NF-κB activity, TAK1 levels and growth of pancreatic cancer cells. We also observed reduction in the levels of TAB1 and TAB2, binding partners of TAK1, upon pharmacological inhibition of GSK-3. Additionally, pharmacological inhibition of GSK-3 significantly suppressed the levels of TAK1 and the growth of human pancreatic tumor explants in mice. Recently non-canonical or IKK- independent NF-κB signaling was also observed to be constitutively active and contributing to cell survival in pancreatic cancer cells. Preliminary data from si-RNA mediated knockdown studies suggests a positive regulation of non-canonical NF-κB signaling by GSK-3α. Overall, our data suggests that constitutive TAK1/TAB1-IKK and non-canonical NF-κB signaling in pancreatic cancer is driven by novel GSK-3α dependent mechanisms. These data provide new insight into our understanding of constitutive NF-κB regulation in pancreatic cancer and presents TAK1 as a potential new therapeutic target for this disease. Further investigation is required to understand the mechanism of GSK-3α-TAK1/TAB1 and GSK-3α-non canonical NF-κB regulation and their effect on pro-survival NF-κB signaling in pancreatic cancers.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2892. doi:10.1158/1538-7445.AM2011-2892
Abstract 2928: Regulation of MST1 and MST2 by mTOR and androgen receptor signaling in prostate cancer
Authors: Collak Filiz Kisaayak , Luthringer Daniel , Kim Hyung L. , Chung Leland , Cinar Bekir 
Published: June 2012

Abstract
The serine/threonine kinases MST1 and MST2 (hippo in Drosophila) were originally identified as pro-apoptotic proteins. In addition to their pro-apoptotic functions, evidence suggests that deficiency in MST1 and MST2 and their downstream effectors has been linked to developmental defects, tissue overgrowth, and cancer, including prostate cancer (PCa). However, the molecular mechanism that may modulate MST1 or MST2 signaling in PCa cells remains unknown. Here we investigate the impact of androgen receptor (AR) and PI3K-AKT-mTOR signaling on MST1 or MST2. We used biochemical, mutagenesis, histochemical, and pharmacological approaches to carry out this investigation. First, we demonstrate that AR and MST1 co-localize and form protein complexes in cell nuclei. Androgen further stimulates the interaction between the two proteins and reduces MST1 kinase activity in LNCaP PCa cells, suggesting that AR may sequester MST1 in an inactive form. Second, we showed that MST1 at Threonine120 (T120) was exclusively phosphorylated in cell nuclei, whereas MST2 at Threonine117 (T117), corresponding to MST1-T120, was phosphorylated only in the cytoplasm, although MST1 and MST2 were found in both locations. Similar phosphorylation patterns were also observed in prostate cancer tissue samples. Third, we have found that the T120 is not a physiologic target of AKT kinase in vivo, because the inhibition of AKT activity by a specific PI3K inhibitor, LY294002, had no effect on the phosphorylation of MST1 at the T120 site, but it did inhibit MST1-T117 phosphorylation. Furthermore, attenuation of mTOR activity by Ku0063794, a specific mTOR1 and mTOR2 inhibitor, abolished MST2-T117 phosphorylation, but without having an effect on the levels of phospho-MST1-Thr120. Lastly, the use of combined LY294002 and Ku0063794 compounds synergistically inhibited PCa cell growth, relative to a single compound. Our data suggest that AR and mTOR pathway signaling may oppose MST1 and MST2 in discrete cell locations. Thus, understanding the functional relationship between these signal networks in the context of cell proliferation and cell death may have important therapeutic implications in prostate cancer.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2928. doi:10.1158/1538-7445.AM2011-2928
Abstract 2933: Inhibition of MAPK signaling prevents Fra-1-mediated CD44 expression in human brain tumor cells
Authors: Beasley Selina A. , Raines Timothy A. , Martin Patrick M. 
Published: June 2012

Abstract
Glioblastoma multiforme (GBM) is a grade IV brain tumor that exhibits a high growth rate and the capacity to invade surrounding tissue. The invasive capacity displayed by GBM cells is a major reason patients diagnosed with GBMs have poor prognosis. Currently, there are few effective treatment options for GBM. The invasive capacity of GBM cells has been associated with CD44, a transmsmbrane glycoprotein. CD44 is a cell surface receptor for hyaluronic acid (HA) which is a major component of the extracellular matrix that comprises the brain. Recent studies demonstrate that CD44 expression has been associated with fos related antigen 1 (Fra-1) an AP-1 transcription factor in GBM. Specifically, our lab has shown that reducing Fra-1 protein levels with siRNA results in decreased amounts of CD44 protein. To better understand Fra-1 regulation of CD44 we examined the signaling mechanisms that mediate Fra-1-regulated CD44 expression. Several human GBM cell lines (U-251 MG, U-1242 MG, and A-172) were treated with epidermal growth factor (EGF 20ng/ml) at various time points to determine the role of EGF stimulation on Fra-1 and CD44 protein expression. In addition to EGF cells were treated with inhibitors to four known signaling pathways: PI3 kinase (LY 294002, 20µM); mTOR (rapamycin, 25nM); Jun kinase (SB203580, 20 µM); and MAP kinase (U-0126, 20µM) to determine whether these pathways mediate Fra-1-regulated CD44 expression. Western blot analysis was used to determine the level of protein expression of Fra-1 and CD44 following inhibitor treatment. Inhibition of the MAPK pathway demonstrated a significant decrease in Fra-1 and CD44 protein levels while inhibition of the AKT and mTOR signaling pathways respectively, exhibit less regulation of Fra-1 and CD44 levels. In addition to determining the regulation of Fra-1 and CD44 protein expression we also assayed the mRNA levels of Fra-1 and CD44 following inhibitor treatment. Fra-1 and CD44 mRNA levels decreased following U-0126 treatment, correlating the decrease of mRNA levels with the decrease of protein expression described previously. Taken together these data suggest that the MAP kinase pathway is responsible for regulating Fra-1-mediated CD44 mRNA and protein expression in malignant brain tumor cell lines.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2933. doi:10.1158/1538-7445.AM2011-2933
Abstract 296: Characterization of prostate cancer circulating tumor cells using E-selectin coated-microtubes
Authors: Gakhar Gunjan , Geng Yue , Jodari-Karimi Mona , Tagawa Scott , Bander Neil , King Michael , Nanus David 
Published: June 2012

Abstract
Background: Metastasis and invasion is facilitated by adhesion of circulating tumor cells (CTCs) to endothelial cells in the blood vessel. Initial recruitment of CTCs to the blood vessel endothelium is mediated through selectin proteins. We used microtube coated with selectin proteins to simulate CTC adhesion under flow, to elucidate the complex physicochemical dynamics that control CTC adhesion in the bloodstream.
Methods: Sterilized microrenathane microtubes were functionalized by E-selectin +/- anti-PSMA (mAb J591) and anti-EpCAM antibodies. Functionalized microtubes were used to observe the rolling behavior of prostate cancer cell lines MDAPCa2b, LNCaP C4-2, and PC-3. MDAPCa2b cells alone or mixed with normal peripheral blood mononuclear cells (PBMCs) were incubated with fluorescently conjugated mAbJ591, and the mixture flowed through the microtube for identification and capture efficiency. PBMCs isolated from prostate cancer patient's blood were similarly processed.
Results: MDAPCa2b cells showed robust rolling at 1 dyne/cm2 shear stress while LNCaP, C4-2, and PC-3 cells did not exhibit rolling behavior on E-selectin coated microtubes. 7.5 cells were observed rolling at 1 dyne/cm2 compared to 1.5 cells at 8 dyne/cm2 per 100 mm2 area. To determine if prostate cancer cells could be identified in a mixture of PBMCs, MDAPCa2b cells were spiked in PBMCs and labeled with fluorescently conjugated mAb J591. MDAPCa2b cells demonstrated selective fluorescence which did not alter their rolling behavior. A 50% capture efficiency of MDAPCa2b cells spiked in PBMCs was achieved when flowed through E-selectin and anti-PSMA coated microtube. After establishing rolling and selective fluorescence in prostate cancer cell line, we used prostate cancer patient's blood. CTCs in prostate cancer patient's blood showed rolling behavior on E-selectin coated microtube. Further, these CTCs were PSMA-positive after incubation with fluorescently conjugated mAbJ591 and easily identified during the flow through the microtube.
Conclusion: Our data shows that CTCs in prostate cancer patients exhibit rolling behavior, which may facilitate invasion and metastasis. Further, selective ex vivo labeling of CTCs enables rapid identification for subsequent characterization of their adhesion and invasive phenotype.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 296. doi:10.1158/1538-7445.AM2011-296
Abstract 2990: Characterization of a mitotic interaction of ATM with AuroraB
Authors: Danforth Rebecca L. , Tang Xi , Yang Chunying , Xu Bo 
Published: June 2012

Abstract
Ataxia-telangiectasia mutated (ATM) is a protein kinase that plays a pivotal role in DNA damage-induced cell cycle checkpoints and DNA repair. Mutation of ATM leads to the autosomal recessive disorder ataxia-telangiectasia, characterized by comprehensive clinical phenotypes such as cancer predisposition and neurodegeneration. One of the cellular phenotypes of ATM-deficiency is the spindle assembly checkpoint (SAC) defect and aneuploidy, indicating that ATM has a functional role in mitosis. We have recently demonstrated that ATM is activated in mitosis and that ATM is required for SAC. The molecular mechanism of mitotic ATM activation has started to emerge. We show here using coimmunoprecipitation that ATM interacts with Aurora B in unsynchronized cells and that this interaction increases during mitosis. Aurora B is a protein kinase and mitotic chromosomal passenger involved in the progression of mitosis. Although regulation of the Aurora B activity in response to DNA damage is dependent on ATM, Aurora B appears to serve as an upstream element of the mitotic ATM activation pathway. Aurora B phosphorylates ATM at Ser1403 and this phosphorylation event is required for activation of the SAC. We also show that Ser1403 is dephosphorylated by Protein Phosphatase 1 (PP1), thus implicating PP1 in the regulation of mitosis and the SAC. We demonstrate that the interaction between ATM and Aurora B is partially dependent on the enzymatic activity of both proteins. We also characterize the protein domains essential for the interaction of ATM with Aurora B and study the functional significance of this interaction. These data expand to our understanding of the roles of ATM outside of DNA damage repair and link ATM to cell cycle control.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2990. doi:10.1158/1538-7445.AM2011-2990
Abstract 3024: Methylation analysis of the VDR gene in ovarian normal and tumorous tissue
Authors: Poulin Matthew , Meyer Ann , Bartley Andrew , Guo Qin , Xu Jessica , Yan Liying 
Published: June 2012

Abstract
Ovarian cancer remains the most lethal gynaecological cancer. Various molecular changes have been identified and have shown promise for their diagnostic, prognostic and curative capacity but still need further validation. Vitamin D has been shown to play a role in the suppression of tumor growth and in the modification of some properties of fully transformed malignant cells. In light of evidence for promoter methylation of the vitamin D receptor in the control of the expression of this gene, we have designed methylation assays that cover many regions of this gene in order to determine its methylation profile in normal individuals, ovarian tumors and ovarian cell lines. This gene is highly polymorphic and SNP assays were also designed to analyze the genetic variability within the VDR gene as well. In order to determine if the methylation state and/or the genetic make-up within the VDR gene plays a role in ovarian cancer we analyzed 76 CpG sites and 20 SNPs in normal male blood DNA and tumor sample DNA. We determined the base-line methylation and genetic state in a non-cancerous sample and found that the promoter region from -700 from the transcriptional start site, through the 5’UTR and into intron 1 shows very low or no methylation. Conversely the CpG sites at the intron 10/Exon 11 boundaries were very highly methylated in normal blood DNA. We examined these same regions in 10 sets of ovarian tumors and their corresponding normal surrounding tissue. There is a small increase in methylation around -700 region in the tumor tissue compared to the normal blood DNA. Some cell line showed higher levels of methylation as well. COV318 has an elevated level of methylation and so has SKOV, OB58, and OV17r. There was no significant difference, however, between tumor/normal samples starting from -500 into intron 1. The methylation level in these samples is all very low. Within the intron 10/exon 11 region, a majority of the tumors show slightly higher levels of methylation than the normal tissue. The T&gt;C SNP rs731236 at the intron 10/exon 11 boundary is within a CpG site that gives an interesting methylation profile between some of the samples that will be presented.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3024. doi:10.1158/1538-7445.AM2011-3024
Abstract 3046: Phosphodiesterase 4D (PDE4D) as a new drug target for prostate cancer
Authors: Hammer Kimberly D.P , Domenech Maribella , Beebe David , Marker Paul C. 
Published: June 2012

Abstract
Our laboratory used an insertional somatic mutagenesis screen in mice to identify novel genes that may drive prostate cancer initiation and progression. Using this screen, we have identified candidate prostate cancer genes including the candidate oncogene phosphodiesterase 4D (PDE4D). Investigation of PDE4D showed that it was over-expressed in human prostate cancer cell lines and in human prostate cancers. Stable knockdown of PDE4D by shRNA reduced the growth and migration of prostate cancer cells in vitro and in vivo. PDE4D has been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD). Several small molecule PDE4D selective inhibitors have been developed and tested in clinical trials for COPD. Although these studies showed that the inhibitors had modest efficacy as a therapy for COPD, they confirmed that the inhibitors were safe for use in humans at doses that inhibited PDE4D in vivo. Based on our previous studies with PDE4D, we postulated that PDE4D small molecule inhibitors would be candidate anti-prostate cancer drugs. Daily oral administration of PDE4D inhibitors, NVP-ABE171 or cilomilast, for 6 weeks significantly reduced the growth of LNCaP-C4 prostate cancer xenografts in immune-compromised mice. Under in vitro conditions in which prostate cancer cell growth was inhibited by either NVP-ABE171 or cilomilast, we also observed changes in the activation of potential downstream molecular targets of PDE4D inhibition. Affected pathways included the sonic hedgehog and mitogen-activated protein kinase pathways. We also tested the potential role of the PDE4D pathway in prostate cancer stromal-epithelial interactions by modeling these interactions using novel microchannel co-culture devices. In this context, PDE4D inhibitors reduced the activation of Shh pathway target genes in mesenchymal cells and reduced the proliferation of epithelial cancer cell lines, supporting the potential importance of the PDE4D pathway for prostate cancer stromal-epithelial interactions. We are continuing in vitro and in vivo studies with these candidate drugs to further support the use of NVP-ABE171 and cilomilast as anti-prostate cancer drugs and to understand their mechanism of action.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3046. doi:10.1158/1538-7445.AM2011-3046
Abstract 3065: Is cytology a suitable source of NSCLC tumor material for EGFR mutation testing
Authors: Dalgliesh Gillian L. , Donald Emma , Sahoo Rashmita , Patil Geeta , Augustus Meena , McCormack Rose , Ellison Gillian 
Published: June 2012

Abstract
Somatic mutations in the epidermal growth factor receptor (EGFR) affect non small cell lung cancer (NSCLC) sensitivity to the EGFR tyrosine kinase inhibitor gefitinib. In many countries, prospective testing of NSCLC patients for EGFR mutations is required to determine patient suitability for gefitinib. Mutation profiling is usually performed on DNA extracted from tumour biopsy samples, however the acquisition of biopsy material from NSCLC patients is often difficult and, in some cases is not available, as diagnosis is routinely made by other means. Diagnostic cytology samples, obtained by fine needle aspiration (FNA), may provide an additional source of tumour material for molecular analysis. The aims of this project were to assess the suitability of FNA for EGFR mutation testing and optimisation of DNA extraction and mutation detection methods suitable for analysis of FNA material. FNA smears of 3 human cell lines, obtained from mouse xenografts, were used to optimise DNA extraction methods. DNA was extracted from diagnostic FNA smears or paraffin embedded FNA derived cells, from 25 NSCLC patients of Indian origin, using the optimised protocols. Following successful DNA extraction from all patient samples, EGFR mutation status was determined by both DNA sequencing and using the therascreen EGFR Mutation Test Kit (L858R and exon 19 deletion mutations only). Twelve of the 25 patients harboured an EGFR mutation. For this sample type, the therascreen EGFR Mutation Test Kit was more effective at identifying mutation positive patients with only 4 of 12 detected mutations also evident by DNA sequencing. DNA extracted using a spin column based kit and quantified by real time PCR prior to performing molecular analysis gave the most robust, reproducible results. In conclusion, these data suggest that diagnostic FNA smears or cell blocks are suitable for assessing EGFR mutation status of NSCLC patients and may prove a useful source of tumour material when biopsies are unavailable.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3065. doi:10.1158/1538-7445.AM2011-3065
Abstract 3074: Identification of a predominant pattern of co-regulation among kinetochore genes; prospective regulatory elements, and association with genomic instability
Authors: Reinhold William C. , Erliandri Indri , Liu Hongfang , Zoppoli Gabriele , Pommier Yves , Larionov Vladimir 
Published: June 2012

Abstract
The NCI-60 cell line panel is the most extensively characterized set of cells in existence. It provides multiple forms of data on different cancer types, and has been used extensively as a screening tool for drug discovery. Previously, the potential of this panel has not been applied to the fundamental cellular processes of chromosome segregation. In the current study, we used data from multiple microarray platforms accumulated for the NCI-60 to characterize an expression pattern of genes involved in kinetochore assembly. This analysis revealed that 17 genes encoding the constitutive centromere associated network of the kinetochore core (the CCAN complex) plus four additional genes with established importance in kinetochore maintenance (CENPE, CENPF, INCENP, and MIS12) exhibit similar patterns of expression in the NCI-60, suggesting a mechanism for co-regulated transcription of these genes which is maintained despite the multiple genetic and epigenetic rearrangements accumulated in these cells (such as variations in DNA copy number and karyotypic complexity). Several potential regulatory influences are identified for these genes, including transcription factors and microRNAs. Thus, our results provide a template for experimental studies on regulation of genes encoding kinetochore proteins, the process that, when aberrant, leads to the aneuploidy that is a hallmark of many cancers. We propose that the comparison of expression profiles in the NCI-60 cell line panel could be a tool for the identification of other genes groups whose products are involved in the assembly of organelle protein complexes.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3074. doi:10.1158/1538-7445.AM2011-3074