bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 1269: Activation of diverse signaling pathways in pancreatic cancer revealed by phosphoproteomics
Authors: Kim Min-Sik , Chaerkady Raghothama , Wu Xinyan , O'meally Robert , Kuppireddy Sarada Vineela , Zhong Jun , Jacob Harrys KC , Marimuthu Arivusudar , Kashyap Manoj K. , Cole Robert , Iacobuzio-Donahue Christine , Maitra Anirban , Pandey Akhilesh 
Published: August 2012

Abstract
Pancreatic cancer is the fourth leading cause of cancer-related deaths in the United States. A number of genes that have somatic mutations including CDKN2A, SMAD4, TP53 and KRAS have been linked to pancreatic cancer. Recently, a comprehensive genomic analysis was performed in a panel of 14 primary pancreatic cancer cell lines and 10 xenografts, in which ∼1,500 somatic alterations were identified and a core set of 12 activated signaling pathways were defined. We decided to use a phosphoproteomics approach to identify tyrosine kinase signaling pathways that could serve as attractive therapeutic targets. Based on immunoblotting with anti-phosphotyrosine antibodies, we observed a heterogeneous pattern of tyrosine phosphorylation in the 14 primary pancreatic cancer cell lines whose genomes have been sequenced previously, which indicated that different tyrosine kinases were likely activated in different cells. To identify these kinases, phosphotyrosine-containing peptides were enriched by immunoprecipitation by anti-phosphotyrosine antibodies and analyzed on a high resolution Fourier transform mass spectrometer coupled to nanoflow reversed phase liquid chromatography. W employed the SILAC methodology to quantitate tyrosine phosphorylated peptides across the panel of cell lines. Our preliminary data indicates that the approach used in this study is suitable for global profiling of tyrosine kinase pathways that are abnormally activated in cancers. The differential alteration of tyrosine kinases was confirmed from the accurate quantitative tyrosine phosphoproteomic analysis. For example, HPNE, a normal pancreatic cell line showed the lowest level of phosphotyrosine levels, while each pancreatic cancer cell line could be differentiated based on its own set of activated tyrosine kinases. Interestingly, some of tyrosine kinases were activated in a small number of cell lines (e.g. AXL, SYK, DDR2, RON and RET), while other tyrosine kinases were found to be activated more broadly (e.g. YES1, TYK2, EPHA2 and EPHB4). Overall, we conclude that these aberrantly activated tyrosine kinases could be targeted to develop newer therapeutic regimens.
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 1269. doi:1538-7445.AM2012-1269
Abstract 1272: MALDI imaging and next generation sequencing for dissecting prostate cancer heterogeneity
Authors: Stahl Phillip , Wurlitzer Markus , Schlüter Hartmut , Thiele Herbert , Becker Michael , Simon Ronald , Weischenfeldt Joachim , Korbel Jan , Minner Sarah , Sauter Guido 
Published: August 2012

Abstract
Prostate cancer is often heterogeneous with multiple tumor foci within the same prostate. MALDI (Matrix-Assisted Laser Desorption/Ionization) mass spectrometry imaging (MSI) allows for a comprehensive profiling of the molecular phenotype on the protein, peptide, lipid, and metabolite level across entire tissue slides without prior enrichment of tumor cells. This study aims in a MALDI-based discrimination of cancer areas that are heterogeneous with respect to morphology and molecular features. We established a method for cryopreservation of entire prostates from cancer patients, and build tissue microarrays from individual cancerous prostates representing &gt;30 different areas of the primary tumor as well as multiple lymph node metastases. We analyzed these arrays for ERG fusion by FISH and for peptide signatures by MALDI MSI. In addition, 2 selected tumor areas and 4 different lymph node metastases from one prostate were subjected to paired end next generation sequencing. MALDI identified 5 masses that were specific for epithelial cells. One particular mass was strongly related to presence of ERG fusion. In one prostate, we identified another mass that was present only in 2/35 tissue spots from the primary tumor as well as in 4/10 lymph nodes. Deep sequencing of different tumor areas of this case identified distinct patterns of structural genetic alterations. A cluster analysis showed that all samples were clonally related, and identified the area inside the primary tumor that gave rise to the metastases. In conclusion, these data suggest that MALDI imaging and next generation sequencing allow for identification of genetic and proteome patterns that correspond to metastatic spread of prostate cancer cells. A combination of both techniques is suited to dissect the genetic background of distinct MALDI signatures.
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 1272. doi:1538-7445.AM2012-1272
Abstract 1291: Tumor growth inhibitory effect in EIF4B silenced in vitro and in vivo lung cancer models
Authors: Shin Jung-Young , Zhang Xiang-Hua , Kim Jeong-Oh , Oh Ji-Eun , Chae Hiun Suk , Joe Young Ae , Kang Jin-Hyoung 
Published: August 2012

Abstract
Backgraound The eIF4B, a key molecule for initiation of protein translation, play an important role in cell growth, proliferation and survival. We investigated that eIF4B is associated with the molecular mechanism of de novo resistance against EGFR TKIs and its role on cell proliferation and survival in NSCLC cells. Method Among five NSCLC cell lines harboring EGFR and K-RAS wild type, PC14 cells showing the highest IC50, were selected for our experiment. In eIF4B silenced PC14 cells by shRNA, we evaluated cell proliferation by direct cell counts and SRB assay and cell cycle distribution using flow cytometry. The expression of signal molecules, transcription factors and apoptosis associated proteins was measured by Western blot. In vivo tumor model established by subcutaneous injection of eIF4B silenced PC14 cells, the retardation of tumor growth was measured. Results In PC14 cells transformed with eIF4B shRNA, we observed the protein expression of eIF4B was reduced (&gt;70% at day 5). The proliferation of eIF4B silenced cells was greatly inhibited both in vitro and in vivo tumor model. Between eIF4B silenced cells and control cells, there was no significant difference in anti-proliferative activity of several target inhibitors (enzastaurin, gefitinib, LY294002, vandetanib) against EGFR-PI3K-AKT signaling molecules. The expression of proteins involved in cell survival (pEGFR, pAKT and mTOR), transcription factors (pNFkB and TS) and anti-apoptotic protein (bcl-2), was decreased and apoptosis associated proteins (phospho-p53 and active caspase-3) were increased. The G0/G1 cell fraction in eIF4B silenced cells was reduced (47.3% vs. 55.1% in control cells) and accumulation of apoptotic cells was observed (12.7% vs. 1.5% in control cells; shown as sub G1 population). Conclusion Our results demonstrated that eIF4B silencing resulted in a marked decrease of several anti-apoptotic and pro-proliferative proteins and eIF4B was required for cell proliferation and survival by regulating cell cycle and cell signaling molecules.
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 1291. doi:1538-7445.AM2012-1291
Abstract 1294: Suppression of uPA in chemo-sensitization and p53 regulation in pancreatic cancer cells
Authors: Gorantla Bharathi , Asuthkar Swapna , Estes Norman , Rao Jasti S. , Gondi Christopher S. 
Published: August 2012

Abstract
Despite new knowledge of the molecular profile of pancreatic cancer and its precursor lesions, survival rates have changed very little over the last 40 years. The ability to predict which patients would benefit most from surgical intervention and/or chemotherapy would be a great clinical asset. Researchers have demonstrated that uPA is frequently present in a higher concentration in the serum of pancreaticobiliary cancer patients. It is known that uPA is involved in ECM degradation and has been correlated with malignant transformation of cancer cells. Emerging data have suggested that the capability of a tumor to grow and propagate is dependent on a small subset of cells within a tumor called cancer stem cells (CSCs) or cancer initiating cells. Under in vitro cell culture conditions, these cells possess sphere-forming ability, which is known to be one of the properties of CSCs. Interestingly, the significance of this sphere formation ability still remains unclear. Recent studies have demonstrated that these sphere-forming cells acquired chemoresistance to cisplatin. In the present study, as observed by FACS analysis, we show that a sub-population of MIA PaCa-2 and PANC-1 pancreatic cancer cells possess cancer stem cell properties. RNAi-mediated suppression of uPA in these cells retarded their tumor forming ability in a nude mouse model. We also observed that uPA-suppressed MIA PaCa-2 and PANC-1 cells, after supplementation with uPA protein regained their cancer stem cell phenotype and showed increased expression of Lhx-2. To determine whether these sub-population cells possess any chemoresistance, we treated these cells with varying concentrations of gemcitabine (0-1000 nM) and observed that these cells were resistant to gemcitabine even at the 1000 nM concentration. Further suppression of uPA using siRNA in these cells sensitized these cells to gemcitabine. In addition, to determine whether uPA has any transcriptional role, we examined whether uPA interacted with any known transcription factors we used a TF-protein array. We observed that uPA interacted with Hoxa-5 very strongly. To further determine whether the interaction of uPA with Hoxa-5 invokes any regulatory response, we used a p53 promoter known to possess Hoxa-5 binding regions to drive a Luciferace gene, both with and without the presence of uPA. We observed that uPA retarded p53 promoter activity. Finally, nude mice implanted with MIA PaCa-2 cancer stem cells were susceptible to gemcitabine treatment after uPA downregulation. Taken together, these results indicate that targeting uPA can sensitize chemoresistant pancreatic cells to gemcitabine.
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 1294. doi:1538-7445.AM2012-1294
Abstract 1298: TWIST1 is expressed by cells with fibroblastic phenotype in colon carcinoma
Authors: Irene Gomez , Paloma Martin , Mercedes Herrera , Esther Martinez , Alberto Herrera , Vanesa garcia , javier Silva , Gemma Dominguez , Cristina Peña , Felix Bonilla , Miguel Garcia Jose 
Published: August 2012

Abstract
Twist1 is a highly conserved transcription factor that belongs to the family of basic helix-loop-helix proteins, a family of proteins with well-described functions in cell growth and differentiation, in both vertebrates and invertebrates. TWIST1 is involved in epithelial-to-mesenchymal transition (EMT), especially in invasiveness processes. Recently we have demonstrated that the expression levels of TWIST1 in colon tumor tissues can be considered as a poor prognostic marker (Gomez I et al, Plos One 28; e18023). Following in this research line we are trying to identify the specific cells expressing TWIST1 in the tumor mass, epithelial cells or fibroblastic phenotype cells, as is expected for cells in EMT. With this purpose we have isolated epithelial cells from 52 colon tumor tissues (based on the expression of EPCAM) and fibroblasts from 18 of them (based in the expression of a fibroblastic marker, Miltenyi Biotec), after mechanical cell dissociation of the different cells populations present in the tumor mass. TWIST1 expression profile was also tested in 13 tumor colon-derived cells and in the immortalized normal fibroblasts, IMR90. First we found that while 51.9 % of tumors samples expressed TWIST1, this only occurred in 1 out of 13 colon carcinoma cell lines tested, besides the IMR90 fibroblasts. Moreover, expression of TWIST1 was never detected in the epithelial fractions but was detected in 17 out of 34 non-epithelial fractions and in 10 out of the 18 samples where fibroblasts were specifically isolated. The absence of epithelial markers, Ber-EP4 and CD326 according with our isolation system, and CK18 and E-cadherin, verified by subsequent western blot, in the cells expressing TWIST1, suggests a non-epithelial origin of this cell population. Additionally, IMR90 fibroblasts co-cultured with LS174T or SW620 colon carcinoma cells showed increased TWIST1 expression (p = 0.002; p = 0.009 respectively), which was associated to up-regulation of the myofibroblast marker α-smooth muscle actin (α-SMA). Finally, there was a correlation between TWIST1 mRNA levels and tumor desmoplasia degree among those TWIST1 positive cases. We conclude that TWIST1 expression in colon adenocarcinomas corresponds to carcinoma-associated fibroblasts and could be implicated in their activation process.
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 1298. doi:1538-7445.AM2012-1298
Abstract 1302: Effect of intestinal-specific Kaiso overexpression on the APC MIN/+ mouse colon cancer model
Authors: Wojtal Daria , Chaudhary Roopali , Nanan Kyster K. , Morone Simona , Daniel Juliet M. 
Published: August 2012

Abstract
The canonical Wnt signaling pathway is a crucial regulator of various cellular processes during embryogenesis but when aberrantly activated, it leads to tumorigenesis. The key downstream effector of the Wnt pathway is the Armadillo protein, β-catenin, which was first characterized as a cytoplasmic cofactor for the transmembrane, cell-cell adhesion tumor suppressor, E-cadherin. Recent evidence from our lab and others indicates that another E-cadherin cofactor, p120ctn and its binding partner, the POZ-ZF transcription factor Kaiso, co-regulate a subset of Wnt/β-catenin target genes and antagonize Wnt signaling. Specifically, using a Xenopus model system, we and others found that Kaiso overexpression rescued the β-catenin-induced duplicate axis phenotype; this implicated Kaiso as a negative regulator of Wnt signaling. However, it remains to be determined whether an analogous antagonistic role for Kaiso is conserved in mammals. Indeed, when Kaiso-null mice (which were viable and had no overt developmental defects or tumors) were crossed with the APCMIN/+ mouse model of colon cancer, the progeny had delayed tumor onset and reduced polyp size. This suggested that Kaiso played a positive role in tumor initiation and possibly cell proliferation in mammals. To resolve this discrepancy, we generated intestine-specific Kaiso overexpressing transgenic mice (KaisoTg/+) for subsequent mating with the APCMIN/+ mouse model of colon cancer. Histological analysis of small and large intestines from KaisoTg/+ and non-Tg mice revealed no gross morphological differences. Immunohistochemical (IHC) and immunofluorescence (IF) staining revealed strong nuclear Kaiso staining in intestinal tissues from KaisoTg/+ mice whereas intestinal tissues from non-Tg mice displayed weak cytoplasmic or no Kaiso staining. We detected no difference in β-Catenin expression levels in tissues from KaisoTg/+ mice and their wildtype littermates. This suggests that Kaiso's regulation of WNT signaling is downstream of its main effector β-Catenin. KaisoTg-APCMIN/+ double mutant mice have been generated and surprisingly they display decreased body size and weight, and have a decreased life span when compared to the parentals (i.e. KaisoTg or APCMIN/+). Current studies are aimed at assessing polyp formation and elucidating the expression levels of p120ctn, β-catenin, E-cadherin and cyclinD1 in the KaisoTg-APCMIN/+ intestines.
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 1302. doi:1538-7445.AM2012-1302
Abstract 1303: The Wilms’ tumor gene, WT1, regulates E-cadherin expression and migration of prostate cancer cells.
Authors: Brett Adina , Fraizer Gail 
Published: August 2012

Abstract
Carcinoma of the prostate is one of the most common malignancies and second leading cause of death among American men. Even though patients with localized disease have high survival rates, patients with detectable metastasis have a median survival of only 12-15 months. One key step in the metastatic process is the loss of E-cadherin expression associated with tumor invasion. However the regulation of E-cadherin gene expression in prostate cancer (PrCa) cells is not well understood. Recently, the zinc finger transcription factor, WT1 was shown to regulate E-cadherin in NIH 3T3 cells and epicardial cells. We have previously reported the presence of WT1 protein in high grade prostate tumor sections, with little or no WT1 staining in non-neoplastic or benign prostatic hyperplasia (BPH) tissues. However, the significance of WT1 expression in prostate cancer has not been established. The objective of this study was to determine whether WT1 might contribute to increase migration of PrCa cells by repressing E-cadherin expression. Using quantitative real-time PCR (QRTPCR), WT1 and E-cadherin mRNA levels were measured and found to be inversely related in PrCa cells. Similarly, QRTPCR results showed a decrease in E-cadherin mRNA in GFP/WT1 transfected PrCa cells, while E-cadherin levels were increased in PrCa cells with suppressed WT1 expression. Titration of WT1 levels also affected the migration of PrCa cells in wound healing and transwell migration assays. Silencing of WT1 by siWT1 RNA decreased the migratory potential of PC3 cells and the overexpression of GFP/WT1 increased the migration of LNCaP cells. A bioinformatics approach was used to identify potential WT1 binding sites in E-cadherin promoter, then direct in vivo binding of WT1 to the E-cadherin promoter in the chromatin of PrCa cells was confirmed by Chromatin Immunoprecipitation. Transcriptional control was quantified by co-transfection of a GFP/WT1 expression construct with E-cadherin promoter constructs. Results showed that WT1 decreased the activity of the proximal E-cadherin promoter in PC3 cells and DU145 cells. Using site directed mutagenesis, a newly identified WT1 binding site located 146 bp from the transcription start site was shown to be required for the repression of the E-cadherin proximal promoter by WT1. Overall these results demonstrate that WT1 transcriptionally down-regulates E-cadherin expression and thereby increases migration of PrCa cells. This finding suggests that the biological significance of WT1 expression in high grade prostate cancer lies in its contribution to cell migration and potentially to the promotion of metastasis. Supported by NIHR15CA11360 and the Ohio Board of Regents.
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 1303. doi:1538-7445.AM2012-1303
Abstract 1427: Signal rewiring induced by EWS/FLI-1 in mouse and human mesenchymal stem cells
Authors: Marques Michelle , Nieves Bethsaida , Chen Ron , Vaka Dideepya , Chan Charles , Zheng Grace , Chang Howard , Weissman Irv , Sweet-Cordero Alejandro 
Published: August 2012

Abstract
Translocations involving members of the Ets family of transcription factors are common in prostate cancer and sarcomas, yet their effects on signal rewiring in cancer are unclear. Translocations between EWS and the Ets transcription factor Fli1 are found in Ewing's sarcoma, an aggressive tumor found in children and young adults. To elucidate the mechanism of transformation by EWS-Fli1, we have developed a novel approach that leverages the advantages of both mouse and human model systems. A knock-in mouse in which a Fli1-cDNA was introduced downstream of the endogenous EWS allele was generated. To our knowledge, this is the first described genetically engineered model in which EWS-Fli1 (EF) can be expressed conditionally from the native EWS promotor. Expression of EF in MEFs and MSCs from this model demonstrates that MSCs tolerate EF expression better than MEFs, consistent with prior data suggesting that MSCs are the likely cell of origin of Ewing's sarcoma. Ongoing analysis of well-defined MSC subsets may provide additional information regarding the cell of origin. In parallel, we have analyzed the consequences of expression of EF in human MSCs derived from pediatric patients. Deep-sequencing of these human pediatric MSCs (hpMSCs) has identified many novel coding and non-coding transcripts that are specifically upregulated in hpMSCs as a consequence of expression of EF. We have used functional analysis using hMSC and ES cell lines to validate the role of these genes in EWS pathogenesis. Some, but not all of these novel transcripts are also upregulated in mouse MSCs and MEFs that express EF. In summary, a cross-species approach that combines mouse genetics with functional genomics has identified novel targets for ES specific therapeutic development.
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 1427. doi:1538-7445.AM2012-1427