bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 5065: Role of EpCAM in EGFR signaling and tumorigenesis
Authors: Muhoro Lincoln , Fleming Timothy , Sankpal Narendra , Gillanders William 
Published: July 2016

Abstract
EpCAM is a transmembrane glycoprotein that functions as a homophilic cell adhesion molecule. EpCAM is expressed in normal epithelium and at even higher levels in epithelial cancers, including breast, pancreatic and lung cancers. Since its discovery in the 1980s, EpCAM has been targeted in several different epithelial cancers. Even though numerous novel therapeutic strategies targeting EpCAM have been investigated, the biological role and functional significance of EpCAM expression in cancer remains unclear. EpCAM expression appears to be associated with prognosis in several epithelial cancers -in some cancers it is associated with a favorable prognosis (renal cell, rectal) and in others it is associated with a poor prognosis (lung, pancreatic, breast). Thus, the function of EpCAM appears to be context-dependent in epithelial cancers. To understand the impact of EpCAM in human cancer, we specifically ablated EpCAM expression in over 40 cancer cell lines, and assessed the impact on invasion. We identified the A431 epidermoid cancer cell line as a cell line that overexpresses EpCAM, but is exquisitely sensitive to manipulation of EpCAM expression. A431 is known to overexpress EGFR and serves as a model cell line for EGFR signaling. Specific ablation of EpCAM significantly enhanced the migration and invasion of the A431 cell line. Specific ablation of EpCAM was also associated with increased EGFR activity, as demonstrated by phospho-immunoblot. Immunoprecipitation studies demonstrate that EpCAM binds directly to EGFR. Using specific EpCAM mutant constructs, we showed that the N-terminal domain of EpCAM is required for binding and suppression of EGFR activity. Using a soft agar colony growth assay, we were able to confirm that N-terminal EpCAM domain mutants (NTD288) inhibited colony growth in 3T3-transfected cells relative to the wildtype. In addition, a transformation assay showed that the same N-terminal mutant was able to inhibit transformation of 3T3 cells. To assess the effects of EpCAM ablation on in vivo tumor growth, we specifically ablated EpCAM and then performed tumor challenge experiments using immunocompromised mice. Specific ablation of EpCAM increased tumor growth relative to control. These data suggest that EpCAM may modulate EGFR signaling. Further studies are ongoing to define the mechanisms by which EpCAM inhibits EGFR activity.
Citation Format: Lincoln Muhoro, Timothy Fleming, Narendra Sankpal, William Gillanders. Role of EpCAM in EGFR signaling and tumorigenesis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5065.
Abstract 5067: Casein kinase 2 alpha phosphorylation of cortactin governs actin cytoskeletal regulation of invadopodia function
Authors: Markwell Steven M. , Gatesman Ammer Amanda , Interval Erik T. , Schafer Dorothy A. , Hames River A. , Weed Scott A. 
Published: July 2016

Abstract
Malregulation of signal transduction events controlling cortical actin cytoskeleton dynamics is responsible for to enhancing tumor cell motility and invasion. The actin-binding protein cortactin facilitates branched actin network formation through activation of the actin related protein (Arp) 2/3 complex. Increased cortactin expression due to gene amplification is observed in many cancers, corresponding with increased tumor progression and poor patient outcome. In many cancer types, elevated Arp2/3 complex activation is responsible for driving increased migration and extracellular matrix (ECM) degradation by governing invadopodia formation and activity. While cortactin-mediated activation of Arp2/3 complex has been well established, the objective of this study is to identify upstream signaling pathways responsible for modulating the interaction between cortactin and Arp2/3 complex in invasive carcinoma cells. We have determined that casein kinase (CK) 2α is responsible for disrupting the ability of cortactin to bind and/or activate Arp2/3 complex. CK2α directly phosphorylates cortactin at a conserved threonine 24 (T24) adjacent to the canonical Arp2/3 binding motif in the cortactin amino-terminal acidic (NTA) domain. CK2α phosphorylation of cortactin T24 impairs the ability of cortactin to activate Arp2/3 actin nucleation as determined by spectrofluorometric analysis. Decreased invadopodia formation and ECM degradation activity is observed in head and neck squamous cell carcinoma (HNSCC) cells with shRNA-mediated CK2α knockdown, expression of a CK2α phosphorylation-null cortactin mutant (T24A), and with treatment of the Phase I CK2α inhibitor CX-4945 (Silmitasertib). Collectively, these data suggest that CK2α-mediated cortactin phosphorylation at T24 is a critical event in regulating the interaction with Arp2/3 complex, identifying a key anti-invasive mechanism impacted by targeted anti-CK2α therapeutics.
Citation Format: Steven M. Markwell, Amanda Gatesman Ammer, Erik T. Interval, Dorothy A. Schafer, River A. Hames, Scott A. Weed. Casein kinase 2 alpha phosphorylation of cortactin governs actin cytoskeletal regulation of invadopodia function. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5067.
Abstract 5071: Expression and cellular distribution of Profilin1/VASPp157 and cofilin1/VASPp239 is altered by docosahexaenoic acid and suppresses cancer cell migration and survival
Authors: Ali Mehboob , Heyob Kathryn M. , Rogers Lynette K. 
Published: July 2016

Abstract
The major risk factor for cancer associated death is uncontrolled metastasis and longer cancer cell survival. Mechanisms associated with actin binding protein-mediated actin dynamics and subcellular distributions are not well defined. Secondary messengers (cAMP and cGMP)differentially phosphorylate actin binding proteins like VASP and are associated with actin remodeling in cancer cells. We tested the hypothesis that differential phosphorylation of VASP precipitates association with two additional actin binding proteins, profilin1 and cofilin1. Furthermore, we speculate that the associations of VASP with profilin1 or cofilin1 are causing changes in subcellular location of the protein complexes. Briefly, non-invasive lung epithelial (MLE12) and cancer (A549) cells were treated with 8-Br-cAMP and/or DHA for 6h and 24h. Actin binding proteins (profilin1, cofilin1, VASP, VASPp157and VASPp239) expressions were analyzed by western blot in cell lysate. Wound assay and transwell apparatus were used to study cell migration. Confocal analysis was performed to analyze F-actin content and actin binding proteins at the wound leading edges and in human lung cancer biopsy samples. Flow cytometry, using ki-67, and cleaved-caspase-3 antibodies were performed to study proliferation and cell viability. Our data indicate an association between profilin1/VASPp157 and cofilin1/VASPp239 and changes in the relative cytoplasmic/nuclear distribution of these protein complexes that coincide with the invasive potential of the cell line or tissue. Additional studies showed that docosahexaenoic acid, inhibited cancer cell migration and viability and altered the expression and cellular distribution of profilin1/VASPp157 and cofilin1/VASPp239. In summary, profilin1/VASPp157 and cofilin1/VASPp239 protein complex expression and subcellular distribution could serve as novel, new areas of research, as biomarkers of disease progression, and/or as innovative therapeutic targets against metastasis.
Citation Format: Mehboob Ali, Kathryn M. Heyob, Lynette K. Rogers. Expression and cellular distribution of Profilin1/VASPp157 and cofilin1/VASPp239 is altered by docosahexaenoic acid and suppresses cancer cell migration and survival. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5071.
Abstract 5075: Hedgehog Pathway Transcription Factor Gli1 Promotes Glioma Invasiveness through Up-regulating Aquaporin 1
Authors: Yao Zhenzhen , Yang Chaoxu , Ma Lie , Tan Yexiong 
Published: July 2016

Abstract
Gliomas, especially Glioblastoma multiformes (GBMs) express increased aquaporin1(AQP1) compared to normal brain. AQPs may contribute to brain edema, cell motility, and tumor angiogenesis. Although the physiology of AQP1 has been the subject of several publications, much less is known about the trans-acting factors involved in the control of AQP1 gene expression and the relationship between the regulation of the AQP1 expression and the major intracellular signaling pathways is also poorly concerned. Hedgehog signaling pathway activation is required for sustained glioma growth and survival. playing an important role in the genesis of glioma and In the present study, we report that Gli1, the transcriptional activator of the Hedgehog pathway, is co-expressed with AQP1 in human glioma tissues and can enhance AQP1 gene transcription by binding to conserved core Gli-binding site in the 5’-flanking promoter region of the AQP1. Transfection of 293T and U251 (human glioblastoma cell line) with Gli1 can markedly increase the AQP1 promoter reporter activity and the AQP1 expression level. Moreover, suppressing the Gli1 expression with the specific RNAi can abort this effect. The ChIP and reporter mutation analysis showed that the -406∼-398 region of the AQP1 promoter is essential for regulation activity of Gli1. To elucidate the possible pathophysiological importance of this molecular interaction, we investigated the migration and invasion ability of cell lines expressing different levels of Gli1 and AQP1. The results demonstrated that restoring the AQP1 expression in the Gli1-knockdown cell line can abort the decrease in the migration ability, which suggested that Gli1 may contribute to the invasion ability of glioma cells through AQP1. The up-regulation of Gli1 and its consequences of increased AQP1 in gliomas may provide a new therapeutic target, either as a cell surface marker or as a functional intervention.
Citation Format: Zhenzhen Yao, Chaoxu Yang, Lie Ma, Yexiong Tan. Hedgehog Pathway Transcription Factor Gli1 Promotes Glioma Invasiveness through Up-regulating Aquaporin 1. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5075.
Abstract 5078: Tumor treating fields (TTFields) reduce migration and invasion properties of human glioma cancer cells in vitro
Authors: Schneiderman Rosa S. , Shteingauz Anna , Giladi Moshe , Voloshin Tali , Porat Yaara , Munster Mijal , Blat Roni , Kirson Eilon D. , Weinberg Uri , Palti Yoram 
Published: July 2016

Abstract
The ability of glioblastoma cells to invade adjacent brain tissue remains one of the major obstacles in obtaining therapeutic success. The development of novel treatment modalities that hinder glioma cancer cell motility could therefore facilitate disease control. TTFields are an effective treatment modality delivered via continuous, noninvasive application of low intensity, intermediate frequency, alternating electric fields. This therapy is approved for the treatment of patients with glioblastoma. Previous investigations have shown that TTFields disrupt microtubules and septin filaments, both of which govern key roles in mitosis. The goal of this study was to evaluate the possible effect of TTFields on human glioma cell migration and invasion properties. Four human glioma cell lines: U-87 MG, A-172, LN-229, and LN-18 (ATCC, USA) were treated with TTFields (1.75 V/cm RMS, 200 kHz) for 24 hours using the inovitro system. Cell migration was measured using in vitro wound healing assays. These were analyzed with Image Pro Premier (Media Cybernetics, USA) to determine migration rates. Invasion assays were performed using modified Matrigel coated Boyden chamber. Cells were stained, photographed and counted using image J (NIH, USA).
Application of TTFields in-vitro led to a significant reduction in both migratory and invasive phenotype in all tested cell lines. Specifically, cell migration velocity, as assessed by the wound healing assay, was significantly reduced in U-87 MG (60%, P&lt;0.001), and in A-172 (33%, P&lt;0.001) compared with untreated control cells. The number of invading cells, as assessed by the modified Boyden chamber assay, was reduced in U-87 MG (54%, P&lt;0.01), A-172 (51%, P&lt;0.001), LN-229 (52%, P&lt;0.001) and in LN-18 (30%, P&lt;0.001) compared with untreated control cells.
Our results suggest that human glioma cell motility is impaired by exposure to TTFields. Further studies are needed to elucidate the mechanism by which TTFields disrupts cellular motility in glioma cancer cells.
Citation Format: Rosa S. Schneiderman, Anna Shteingauz, Moshe Giladi, Tali Voloshin, Yaara Porat, Mijal Munster, Roni Blat, Eilon D. Kirson, Uri Weinberg, Yoram Palti. Tumor treating fields (TTFields) reduce migration and invasion properties of human glioma cancer cells in vitro. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5078.
Abstract 5092: CD151-α3β1 integrin complexes are prognostic markers of glioblastoma and cooperate with EGFR to drive tumor cell motility and invasion
Authors: Zhou Pengcheng , Erfani Sonia , Segal Rosalind , Horbinski Craig , Yang Xiuwei H. 
Published: July 2016

Abstract
Glioblastoma, one of the most aggressive forms of brain cancer, is featured by high tumor cell motility and invasiveness, which not only fuel tumor infiltration, but also enable escape from surgical or other clinical interventions. Thus, better understanding of how these malignant traits are controlled will be key to the discovery of novel biomarkers and therapies against this deadly disease. Tetraspanin CD151 and its associated α3β1 integrin have been implicated in facilitating tumor progression across multiple cancer types. How these adhesion molecules are involved in the progression of glioblastoma, however, remains largely unclear. Here, we examined an in-house tissue microarray-based cohort of 96 patient biopsies and TCGA dataset to evaluate the clinical significance of CD151 and α3β1 integrin. Functional, biochemical and signaling analyses were also conducted to understand how these molecules promote the aggressiveness of glioblastoma at molecular and cellular levels. Results from our analyses showed that CD151 and α3 integrin were significantly elevated in glioblastomas at both protein and mRNA levels, and exhibited strong inverse correlation with patient survival (p &lt;0.006). These adhesion molecules also formed tight protein complexes and synergized with EGF/EGFR to accelerate tumor cell motility and invasion. Furthermore, disruption of such complexes enhanced the survival of tumor-bearing mice in a xenograft model, and impaired activation of FAK and small GTPases. Also, knockdown- or pharmacological agent-based attenuation of EGFR, FAK or Graf (ARHGAP26)/small GTPase-mediated pathways markedly mitigated the aggressiveness of glioblastoma cells. Collectively, our findings provide clinical, molecular and cellular evidence of CD151-α3β1 integrin complexes as promising prognostic biomarkers and therapeutic targets for glioblastoma.
Citation Format: Pengcheng Zhou, Sonia Erfani, Rosalind Segal, Craig Horbinski, Xiuwei H. Yang. CD151-α3β1 integrin complexes are prognostic markers of glioblastoma and cooperate with EGFR to drive tumor cell motility and invasion. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5092.
Abstract 5098: In vitro designer microenvironments for modeling the endothelin axis in brain cancer
Authors: Rizzi Simone C. , Mermier Charlotte , Crettaz Sophie , Blumer-Nesca Valeria , Gandar. Céline 
Published: July 2016

Abstract
Preclinical studies in vivo have demonstrated that the endothelin (ET) axis is implicated in drug resistance of several tumors (e.g. brain and ovarian). Indeed, antagonists, blocking the binding of endothelin-1 to endothelin receptors (ETRs) overexpressed by cancer cells, have shown to make tumors more sensitive to conventional chemotherapies. In vitro, however, mechanistic studies have been hampered by the lack of adequate models, in which cell lines sufficiently express all key elements of the ET axis (e.g. ETRs), as they do in xenografts.
We argue that limitations of conventional in vitro systems are mainly due to their inability to take into account the role of the extracellular microenvironment (ME). To overcome these limitations we have exploited the design flexibility of the QGel Matrix technology to identify 3D cell microenvironments that induced cancer cells to naturally express ETRs in vitro. Briefly, brain cancer cells LN229 were grown clonogenically in differently functionalized poly(ethylene glycol) (PEG)-based gels whose biological and biophysical characteristics were combinatorially varied. AlamarBlue™ assays and intracellular calcium release measurements (ICRM) were employed to measure cell growth and functionality of ETRs in the different gel ME over time. All assays were performed in 384-well plate format with liquid handling devices.
ETR expression and functionality was confirmed in control cell lines when grown as clonogenic spheroids in MEs or as monolayer on tissue culture plastic (2D). Likewise, LN229 growth was observed in all tested MEs and in 2D. However, ETR functionality of LN229 differed considerably depending on the ME. For instance, in 2D, ICRM did not show ETR functionality. In contrast, clonogenically grown cell spheroids, in gel MEs containing cell integrin binding sites, showed significantly higher ETR functionality compared to LN229 in control gel MEs. Ongoing studies are further investigating the influence of other matrix characteristics (stiffness and degradability) to optimise expression and functionality of ETRs by LN229 for drug testing applications.
These data suggest that engineered MEs are powerful tools for the development of cell-based assays with enhanced physiological relevance. With their proven compatibility with standard laboratory automation systems and assay miniaturization, these in vitro disease models can be translated to industry for making more relevant decisions on compound efficacy in preclinical tests.
Citation Format: Simone C. Rizzi, Charlotte Mermier, Sophie Crettaz, Valeria Blumer-Nesca, Céline Gandar. In vitro designer microenvironments for modeling the endothelin axis in brain cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5098.
Abstract 5103: Crosstalk between osteoprotegerin (OPG), fatty acid synthase (FASN), and cyclooxygenase-2 (COX-2) in breast cancer: implications in carcinogenesis
Authors: Goswami Sudeshna , Sharma-Walia Neelam 
Published: July 2016

Abstract
The cross-talk between malignant and nonmalignant cells in the tumor microenvironment, as maneuvered by cytokines/chemokines, drives breast cancer progression. We demonstrated that OPG is expressed and secreted at very high levels from the highly invasive breast cancer cell lines SUM149PT and SUM1315MO2 as compared to human normal mammary epithelial HMEC cells (1). OPG was involved in modulating aneuploidy, cell proliferation, and angiogenesis in breast cancer (1). Mass spectrometry analysis performed in this study revealed OPG interacts with fatty acid synthase (FASN), which is a key enzyme of the fatty acid biosynthetic pathway in breast cancer cells. Further, electron microscopy, immunofluorescence, and fluorescence quantitation assay highlighted the presence of a large number of lipid bodies (lipid droplets) in SUM149PT and SUM1315MO2 cells in comparison to HMEC. We recently showed upregulation of COX-2 inflammatory pathway and its metabolite PGE2 secretion in SUM149PT and SUM1315MO2 breast cancer cells (2). Interestingly, human breast cancer tissue samples displayed high expression of OPG, PGE2 and FASN. Immunofluorescence staining exposed the co-existence of COX-2 and FASN in the lipid bodies of breast cancer cells. We reasoned that there might be cross-talk between OPG, FASN, and COX-2 that sustains the inflammatory pathways in breast cancer. Here, we identified cis-acting elements involved in the transcriptional regulation of COX-2 and FASN by recombinant human OPG (rhOPG). Treatment with FASN inhibitor C75 decreased the number of lipid body/cell, downregulated phosphorylation of ERK, GSK3β, and induced apoptosis by caspase-3 and caspapse-9 activation. Collectively, the novel biological cross-talk between OPG, FASN, and COX-2 advocates for combinatorial drug treatment to block these players of carcinogenesis as a promising therapeutic to target highly invasive breast cancer.
References:
1. Goswami, S., & Sharma-Walia, N. (2015). Osteoprotegerin secreted by inflammatory and invasive breast cancer cells induces aneuploidy, cell proliferation and angiogenesis. BMC. http://www.biomedcentral.com/1471-2407/15/935
2. Chandran, K., Goswami, S., & Sharma-Walia, N. (2015). Implications of a peroxisome proliferator-activated receptor alpha (PPARα) ligand clofibrate in breast cancer. Oncotarget, 5. http://www.impactjournals.com/oncotarget/index.php?journal = oncotarget&page = article&op = view&path%5B%5D = 6402
Citation Format: Sudeshna Goswami, Neelam Sharma-Walia. Crosstalk between osteoprotegerin (OPG), fatty acid synthase (FASN), and cyclooxygenase-2 (COX-2) in breast cancer: implications in carcinogenesis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5103.