bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 3322: Spatio-temporal regulation of epithelial transformation by mistrafficking of EGFR ligand, epiregulin
Authors: Singh Bhuminder , Bogatcheva Galina , Washington Mary K. , Coffey Robert J. 
Published: May 2015

Abstract
The EGF receptor (EGFR) ligand epiregulin (EREG) is delivered preferentially to the basolateral cell surface of polarized MDCK cells. Recently, we showed that EREG basolateral trafficking is regulated by a conserved tyrosine residue within a YXXΦ motif (Y156ERV) in its cytoplasmic domain. Interestingly, a Y156A substitution led to apical mistrafficking of EREG and transformation of polarized MDCK cells (PNAS 110: 8960-5, 2013). We have identified EREG mutations (R147stop) in human tumors that would disrupt the basolateral sorting motif of EREG and now report that EREG harboring these patient mutations mistrafficks to the apical surface. We propose that ligand mistrafficking is a driver of transformation rather than being a mere passenger. To test our proposal wild-type and mutant EREG will be inducibly (Tet-ON) expressed at various stages of MDCK cyst formation and maintenance in 3D Matrigel cultures where we have now recapitulated the transformation phenotype induced by EREG-mistrafficking. Results from these experiments will be presented at the meeting.
Citation Format: Bhuminder Singh, Galina Bogatcheva, Mary K. Washington, Robert J. Coffey. Spatio-temporal regulation of epithelial transformation by mistrafficking of EGFR ligand, epiregulin. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3322. doi:10.1158/1538-7445.AM2014-3322
Abstract 3325: Role of AP2A1 in EGFR nuclear translocation and transcriptional activation activity
Authors: Chen Huai-Gu , Hsu Sheng-Chieh 
Published: May 2015

Abstract
The tyrosine kinase activity and endocytosis of epidermal growth factor receptor (EGFR) are activated by ligand binding. The adaptor protein 2 (AP2) complex found in the clathrin coated vesicles mediates intracellular trafficking of EGFR. Accumulating evidence suggest that the nucleus is one of intracellular destination. Nuclear EGFR severs as a transcriptional co-activator to regulate expression of several genes which are involved in tumor growth, progression and drug resistance. The carboxyl terminal 186 amino acids of EGFR has transcriptional activation activity and the AT-rich sequence (ATRS) of the target gene promoter is required for EGFR binding. In the present study, we show that AP2A1, the alpha 1 adaptin subunit of AP2 complex, interact with EGFR not only in the cytoplasm but also in the nucleus. The EGFR-AP2A1 interaction is stimulated by EGF and suppressed by Iressa, a tyrosine kinase inhibitor. Knockdown AP2A1 expression in cancer cells abrogates EGF-induced EGFR nuclear translocation. Interesting, the ATRS reporter activity is enhanced by depletion of cellular AP2A1. These results indicate that AP2A1 is required for EGFR nuclear translocation and suppresses the transcriptional activation activity of EGFR. Thus, we demonstrate here the novel role of AP2A1 in EGFR trafficking and transcriptional regulation.
Citation Format: Huai-Gu Chen, Sheng-Chieh Hsu. Role of AP2A1 in EGFR nuclear translocation and transcriptional activation activity. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3325. doi:10.1158/1538-7445.AM2014-3325
Abstract 3352: miR-122 targets pyruvate kinase M2 and affects metabolism of hepatocellular carcinoma
Authors: Xu Zhi , Liu Angela , Lee Nikki , Chen Jinfei , Luk John M. 
Published: May 2015

Abstract
In contrast to normal differentiated cells that depend on mitochondrial oxidative phosphorylation for energy production, cancer cells have evolved to utilize aerobic glycolysis (Warburg's effect), with benefit of providing intermediates for biomass production. MicroRNA-122 (miR-122) is highly expressed in normal liver tissue regulating a wide variety of biological processes including cellular metabolism, but is reduced in hepatocellular carcinoma (HCC). Overexpression of miR-122 was shown to inhibit cancer cell proliferation, metastasis, and increase chemosensitivity, but its functions in cancer metabolism remains unknown. The present study aims to identify the miR-122 targeted genes and to investigate the associated regulatory mechanisms in HCC metabolism. We found the ectopic overexpression of miR-122 affected metabolic activities of HCC cells, evidenced by the reduced lactate production and increased oxygen consumption. Integrated gene expression analysis in a cohort of 94 HCC tissues revealed miR-122 level tightly associated with a battery of glycolytic genes, in which pyruvate kinase (PK) gene showed the strongest anti-correlation coefficient (Pearson r = -0.6938, p = &lt;0.0001). In addition, reduced PK level was significantly associated with poor clinical outcomes of HCC patients. We found isoform M2 (PKM2) is the dominant form highly expressed in HCC and is a direct target of miR-122, as overexpression of miR-122 reduced both the mRNA and protein levels of PKM2, whereas PKM2 re-expression abrogated the miR-122-mediated glycolytic activities. The present study demonstrated the regulatory role of miR-122 on PKM2 in HCC, having an implication of therapeutic intervention targeting cancer metabolic pathways.
Citation Format: Zhi Xu, Angela Liu, Nikki Lee, Jinfei Chen, John M. Luk. miR-122 targets pyruvate kinase M2 and affects metabolism of hepatocellular carcinoma. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3352. doi:10.1158/1538-7445.AM2014-3352
Abstract 3360: Loss of sulf-1 reprograms energy metabolism in ovarian cancer
Authors: Mondal Susmita , Roy Debarshi , Pereira Juliana Camacho , Chini Eduardo N. , Shridhar Vijayalakshmi 
Published: May 2015

Abstract
We have previously shown that loss of HSulf-1, an endosulfatase that removes 6-O sulfation of HSPGs augmented heparin binding growth factor (HB-GF) signaling resulting in enhanced tumorigenesis, angiogenesis and metastasis in ovarian cancer. However, the role of HSulf-1 in energy metabolism and how the increased growth factor signaling in cells with loss of HSulf-1 altered cellular metabolism in cancer yet to be investigated. Here, we show for the first time that batch clonal lines of HSulf-1 knockdown cells [OV202 (Sh1/2)] and HSulf-1 knock out (KO) MEFs showed a significantly higher glycolytic flux (glucose uptake and lactate production) and reduced oxygen consumption rate (OCR) compared to a non-transduced control (OV202NTC) and wild-type (WT) MEF cells respectively. Conversely, enhanced expression of HSulf-1 in TOV21G cells resulted in lower glycolytic flux and higher OCR. Microarray analysis revealed that several of the genes in the glycolytic pathway such as Glut1, HK2, PFKFB3, ALDOC, PGAM, PKM2 and LDHA were upregulated in Sh1/2, cells compared to NTC cells. Expression of these genes and their respective products were validated both at the mRNA and protein levels in OV202Sh1/2, TOV21G Vec and MEFs KO cells compared to OV202NTC, TOV21G Cl13 and MEF WT respectively. Importantly, we found that loss of HSulf-1 decouples the energy flow from glycolysis to mitochondria by lowering the PDH and up-regulating PDK1 expression. We further demonstrated that loss of HSulf-1 reduced the total cellular ATP levels in Sh1/Sh2, TOV21G VEC, and MEFs KO cells, all consistent with lower mitochondrial activity as evidenced by decreased total number of mitochondria, its cross sectional area and perimeter in Sh1/Sh2, TOV21G Vec and MEF KO cells. This augmented aerobic glycolysis with loss of HSulf-1 was further corroborated by metabolomics study which showed significantly higher glycolytic metabolites such as G-6P, F1,6BP, F2,6BP, 3PG. While most of the TCA intermediates were downregulated in Sh1 and Sh2 cells; glutamate, glutamine, α-ketoglutarate and 2-hydroxyglutarate were higher upon loss of HSulf-1. These results suggests that loss of HSulf-1 plays a pivotal role in reprogramming the energy metabolism towards the Warburg effect which are critical to sustain cancer cells proliferation, transformation and angiogenesis.
Citation Format: Susmita Mondal, Debarshi Roy, Juliana Camacho Pereira, Eduardo N. Chini, Vijayalakshmi Shridhar. Loss of sulf-1 reprograms energy metabolism in ovarian cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3360. doi:10.1158/1538-7445.AM2014-3360
Abstract 337: Carfilzomib synergistically enhances ABT-263-induced apoptosis due to NOXA induction in KRAS wild type and mutant colorectal cancer cell lines
Authors: Huang Shengbing , Okamoto Koichi , Sinicrope Frank A. 
Published: May 2015

Abstract
BACKGROUND. Proteosome inhibition is associated with induction of the proapoptotic BH3 protein NOXA. Therefore, we hypothesize that the combination of the irreversible proteosome inhibitor, carfilzomib, will cooperatively enhance apoptosis induction by the BH3 mimetic drug, ABT-263. Given that nononcogenic addiction to proteosome activity has been reported in KRAS mutant cells, we utilized isogenic colorectal cancer (CRC) cell lines in which the endogenous wild-type (wt) or mutant alleles had been inactivated through targeted homologous recombination. Since proteasome blockade results in proteotoxic stress, we determined whether an autophagy inhibitor can enhance chemosensitivity.
EXPERIMENTAL METHODS. Isogenic KRAS mutant (MUT) CRC cells (HCT116, DLD1; obtained from B. Vogelstein, JHU) were incubated with carfilzomib (25,50nM) alone or combined with ABT-263 (1 µM) and apoptosis was measured by caspase cleavage and annexin V+ labeling. Synergy was measured by calculation of the combination index. Effect of carfilzomib on Bcl-2 family proteins was determined by immunoblotting. Interaction of NOXA with MCL-1 was examined by immunoprecipitation. Knockdown of NOXA was achieved by lentiviral shRNA. Cells were incubated with drugs alone or combined with chloroquine, and autophagy (LC3I/II conversion) and apoptosis were analyzed.
RESULTS. Carfilzomib was shown to potently and synergistically enhance ABT-263-induced apoptosis (2-fold) in both KRAS MUT and wild type (WT) cell lines, with the effect being modestly higher in wild type cells, as shown by annexin V+ staining and caspase cleavage. Carfilzomib induced NOXA expression in both KRAS MUT and WT cells, and reduced MCL-1 expression. Induced NOXA was shown to bind and sequester MCL-1 proteins. Knockdown of NOXA attenuated drug-induced apoptosis. Autophagy inhibition by chloroquine accumulated LC3II, but only modestly increased carfilzomib-induced cell death.
CONCLUSION. Irreversible proteasome inhibition by carfilzomib synergistically enhanced ABT-263-induced cell death that is mediated by NOXA upregulation and its sequestration/neutralization of MCL-1. The finding of similar efficacy in KRAS MUT vs WT cells suggests that this combination may represent a novel therapeutic strategy in this tumor subset.
Citation Format: Shengbing Huang, Koichi Okamoto, Frank A. Sinicrope. Carfilzomib synergistically enhances ABT-263-induced apoptosis due to NOXA induction in KRAS wild type and mutant colorectal cancer cell lines. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 337. doi:10.1158/1538-7445.AM2014-337
Abstract 3372: Constraints-based metabolic flux analysis approach links tumor stage to metabolic adaptations and survival in cancer cells
Authors: Achreja Abhinav , Yang Lifeng , Zhao Hongyun , Marini Juan , Nagrath Deepak 
Published: May 2015

Abstract
The Warburg effect has been observed in many cancers and their high glycolytic capacity has signified their dependence on glucose. More recently, glutamine has emerged not only as an important nutrient for many cancers, but also necessary for their elevated energetic requirements. Due to these high energetic demands, certain cancer cells become addicted to glutamine to maintain viability. We postulate that distinct metabolic reconfigurations of certain cancers define their dependence or independence on glutamine for survival while maintaining their proliferative propensity and redox status. An intricate picture of the metabolic profiles is to be drawn from estimating intracellular fluxes, by combining stable isotope tracer measurements and experimental metabolomics data from different cancer cell lines, which have been observed to be glutamine dependent and independent. To this extent, we describe an approach that utilizes a redox-balanced model incorporating the electron transport chain and comprehensive amino-acid metabolic reactions to elucidate the importance of oxidative phosphorylation, often overlooked in classical approaches. Diving deeper into the foray of metabolic reprogramming, we perform in silico experiments using a constraint-based multi-objective modeling approach. This methodology elucidates the switching of metabolic pathways in glutamine-dependent and -independent cancers under nutrient-available and nutrient-deprived conditions. Our approach assumes that cancer cells operate at optimal levels, maintaining multiple objectives under certain environmental conditions. Constraining the proliferative phenotype from a maximal to minimal levels of the cells under different nutrient conditions emulates the observed behavior of glutamine-dependent cells under deprivation conditions and contrasts their metabolic reprogramming against that of glutamine-independent cells. We corroborated our simulations with experimentally derived metabolic fluxes and found that glutamine anabolism over catabolism dictates adaptations and survival in invasive cancers. Our results will lead to identification of potential targets for inducing nutrient-sensitivity and enhance current therapeutic approaches.
Citation Format: Abhinav Achreja, Lifeng Yang, Hongyun Zhao, Juan Marini, Deepak Nagrath. Constraints-based metabolic flux analysis approach links tumor stage to metabolic adaptations and survival in cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3372. doi:10.1158/1538-7445.AM2014-3372
Abstract 3393: Nuclear receptor Nurr1 mediates cell proliferation and is involved in a p53-microRNA-34 regulatory network
Authors: Beard Jordan A. , Hills Justin L. , Tenga Alexa , Takwi Apana A. , Chen Taosheng 
Published: May 2015

Abstract
Nuclear receptor (NR) subfamily 4 member 2 (NR4A2), also known as Nurr1, has been shown to have oncogenic properties, in which it can mediate cell transformation, migration and drug resistance. However, the manner in which Nurr1 mediates these cancer-promoting features is not completely understood, but research implicates p53 as a potential intermediary. In this study, we show that Nurr1 enhances the proliferative rate of colorectal cancer cells. This increase in cell growth is accompanied by an upregulation of cyclin D3, a putative target gene of Nurr1. To understand how Nurr1 itself is regulated, we performed a reporter screen to identify microRNA regulators of Nurr1's 3’UTR. We identified miR-34c as a putative regulator of Nurr1 and this direct regulation was confirmed through site-directed mutagenesis of the predicted seed region. We next determined if p53 activation could affect Nurr1 expression through transcriptional activation of miR-34. Using Nutlin-3a to activate p53, we found that Nurr1 expression decreased in a dose response manner. Lastly, we sought to determine if Nurr1 could attenuate p53 activation. We found that overexpression of Nurr1 in colorectal cancer cells caused an attenuation of p53 transactivation of target genes following Nutlin-3a treatment. Our results suggest that a p53-miR-34-Nurr1 regulatory network exists, which would allow p53 to maintain Nurr1 in a suppressed state through miR-34-mediated regulation and prevent tumorigenesis. In cases of p53 mutation or Nurr1 overexpression, this network would be compromised, allowing Nurr1 to enhance tumorigenesis or drug resistance.
Citation Format: Jordan A. Beard, Justin L. Hills, Alexa Tenga, Apana A. Takwi, Taosheng Chen. Nuclear receptor Nurr1 mediates cell proliferation and is involved in a p53-microRNA-34 regulatory network. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3393. doi:10.1158/1538-7445.AM2014-3393
Abstract 3396: Dual lineage inhibition of ETV1 and KIT disrupts the ETV1-KIT feed forward circuit and potentiates imatinib antitumor effect in GIST oncogenesis
Authors: Ran Leili , Sirota Inna , Cao Zhen , Murphy Devan , Shukla Shipra , Rossi Ferdinando , Wongvipat John , Tap William D. , Besmer Peter , Antonescu Cristina R. , Chen Yu , Chi Ping 
Published: May 2015

Abstract
Gastrointestinal stromal tumour (GIST) is one of the most common types of human sarcoma and is primarily defined by activating mutations in the KIT or PDGFRA receptor tyrosine kinases. Despite the initial clinical success of imatinib that specifically target mutant KIT and PDGFRA, imatinib resistance has become the biggest challenge in the management of advanced GIST patient. Novel therapeutics that can improve the efficacy of first line imatinib therapy and/or prevent and overcome imatinib resistance is imperative. The ETS family member, ETV1, has been previously identified as a lineage-specific survival factor that cooperates with mutant KIT by ETV1 protein stabilization by active MAP kinase signaling downstream of KIT signaling in GIST oncogenesis. Here we demonstrate that ETV1 is required for GIST initiation and maintenance in vivo using compound genetically engineered mouse models (GEMM). We further identified that ETV1 forms a feed forward circuit in GIST oncogenesis where the ETV1 protein is stabilized by active MAP kinase signaling downstream of KIT and stabilized ETV1enhances KIT expression through direct binding to the KIT enhancer regions in both GIST mouse models and human GIST cell lines. The dual lineage targeting of KIT by imatinib and ETV1 by MEK162 (an MEK inhibitor) disrupts the ETV1-KIT feed forward circuit and induces more apoptosis than single agent imatinib or MEK162 in human GIST cells. The combination therapy resulted in complete tumor regression whereas single agent imatinib or MEK162 resulted in stabilization of disease in human GIST xenograft studies. Moreover, the combination therapy also induced more tumor fibrosis than single agent imatinib or MEK162 in GIST GEMM. These observations demonstrate the in vivo role of ETV1 in GIST oncogenesis and the feasibility of targeting ETV1 protein stability by inhibiting MAP kinase signaling. They also suggest that the dual lineage targeting of ETV1 and KIT by the combination therapy may provide a more effective therapeutic strategy than imatinib alone in GIST management.
Citation Format: Leili Ran, Inna Sirota, Zhen Cao, Devan Murphy, Shipra Shukla, Ferdinando Rossi, John Wongvipat, William D. Tap, Peter Besmer, Cristina R. Antonescu, Yu Chen, Ping Chi. Dual lineage inhibition of ETV1 and KIT disrupts the ETV1-KIT feed forward circuit and potentiates imatinib antitumor effect in GIST oncogenesis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3396. doi:10.1158/1538-7445.AM2014-3396
Abstract 34: The receptor for hyaluronan acid mediator motility (RHAMM, CD168) expression in EMT-like cancer cells is a predictor of tumor progression in colorectal cancer
Authors: Mele Valentina , Koelzer Viktor H. , Huber Bettina , Muraro Manuele G. , Pfaff Dennis , Iezzi Giandomenica , Terracciano Luigi M. , Karamitopoulou Eva , Zlobec Inti , Lugli Alessandro 
Published: May 2015

Abstract
Background/Aim: The receptor for hyaluronan acid mediator motility (RHAMM) is a marker of tumor progression and decreased overall survival in patients with different solid tumor types. The aim of the present study was to investigate the functional and clinical role of RHAMM in colorectal cancer (CRC) using in vitro and in vivo models and to validate the results on a cohort (n=200) of CRC patients with full clinico-pathological features.
Material and Methods: Two established CRC cell lines HT29 and HT116 (mismatch-repair proficient and deficient) expressing RHAMM by flow-cytometry were selected for proliferation, invasion and migration assays. For the in vivo analysis tumor cells were injected in immune-deficient NOD/SCID mice. RHAMM expression was additionally analyzed by immunohistochemistry on 200 CRC whole tissue sections, with particular focus on the single, detached and aggressive EMT-like cells at the invasion front and correlated to clinicopathological data and survival.
Results: In vitro, RHAMM silenced HT29 and HCT116 cell lines showed a significant decrease in invasiveness and migration compared to untreated cells. In vivo, a lower tumorigenicity of HT29 and HT116 cells silenced for RHAMM compared to untreated cells was reflected by smaller tumor volumes in the injected immune-deficient NOD/SCID mice. In the immunohistochemical analysis RHAMM expression in EMT-like cancer cells was associated with lymphatic invasion (p=0.0013), higher tumor grade (p=0.021) and worse survival (p=0.034).
Conclusion: In vitro and in vivo findings as well as results on clinical patient data support the notion that over-expression of RHAMM is involved in tumor progression in CRC and highlight a promising basis for a therapeutic approach.
Citation Format: Valentina Mele, Viktor H. Koelzer, Bettina Huber, Manuele G. Muraro, Dennis Pfaff, Giandomenica Iezzi, Luigi M. Terracciano, Eva Karamitopoulou, Inti Zlobec, Alessandro Lugli. The receptor for hyaluronan acid mediator motility (RHAMM, CD168) expression in EMT-like cancer cells is a predictor of tumor progression in colorectal cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 34. doi:10.1158/1538-7445.AM2014-34