bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract LB-014: Targeting insulin receptor splicing as a therapeutic intervention for pediatric rhabdomyosarcoma
Authors: Chandler Dawn S. , Brown Chelsea , Bid Hemant , Bebee Thomas , Comiskey Daniel F. , Rigo Frank , Houghton Peter J. 
Published: July 2016

Abstract
The insulin receptor (IN-R) alternatively spliced variant A, encoding a receptor lacking exon 11, is the predominant isoform expressed in both pediatric sarcoma cells and vascular endothelial cells. Exon 11 of the IN-R gene is composed of 36 nucleotides that encode 12-amino acids that reside at the carboxyl terminus of the alpha subunit. Though only a small change in the protein composition, deletion of these 12 amino acids results in a receptor that has increased binding affinity for the IGF-2 growth factor and is exquisitely capable of responding to autocrine and paracrine signaling. Cells expressing both the IN-R A variant and the IGF-2 growth factor are therefore programmed for growth and angiogenesis, two essential steps in tumorigenesis. Furthermore, the IGF-2 can maintain angiogenesis through IN-R A when the IGF-1 receptor is blocked. We also demonstrate that hypoxia induces IN-R alternative splicing. This finding is particularly intriguing since recent studies have shown that adaptation to hypoxic environments is a hallmark of the neoplastic phenotype. We therefore hypothesize that the expression of splicing factors is altered by hypoxia leading to the generation of the IN-R A isoform, which contributes to cancer progression beyond the micrometastatic stage.
To characterize sequence elements and RNA binding proteins in the regulation of IN-R alternative splicing, we have designed a hypoxia-induced splicing system that recapitulates the IN-R splicing seen in tumors. We have shown that sequence elements flanking the regulated exon are important for the hypoxia-induced splicing changes. Furthermore, have performed an antisense oligonucleotide (ASO) walk to target these splicing enhancer and repressor sequences to interfere with IN-R splicing. We have successfully targeted the CUGBP1 negative regulator of splicing that resides in intron 10 to increase the IN-R B full-length isoform. We have shown that an ASO used to drive production of the IN-R B isoform in a rhabdomyosarcoma (RMS) cell line, which normally expresses the IN-R A isoform, affects cancer cell behavior to induce reduced motility and cell migration. We therefore postulate that modulation of the splicing of the IN-R, alone or in conjunction with IGF-1R blocking antibodies, could be used as a therapeutic intervention in pediatric RMS cells.
Citation Format: Dawn S. Chandler, Chelsea Brown, Hemant Bid, Thomas Bebee, Daniel F. Comiskey, Frank Rigo, Peter J. Houghton. Targeting insulin receptor splicing as a therapeutic intervention for pediatric rhabdomyosarcoma. [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 LB-014.
Abstract LB-018: Loss of function mutations of an ETS repressor expand the ETS positive subset of prostate cancer
Authors: Bose Rohit , Abida Wassim , Karthaus Wouter , Armenia Joshua , Iaquinta Phillip , Wongvipat John , Doran Michael , Hieronymus Haley , Watson Philip , Sullivan Patrick , Liang Yupu , Schultz Nikolaus , Sawyers Charles 
Published: July 2016

Abstract
Recent genomic profiling of both primary and metastatic prostate cancers has revealed novel loss-of-function point mutations and copy number deletions of the gene ERF, an ETS transcriptional repressor with a nearly identical DNA-binding domain to the TMPRSS2-ERG oncogene product. Furthermore, ERF homozygous loss or point mutations occur exclusive of the ERG upregulation that occurs in 50% of prostate cancers following fusion of androgen-regulated upstream genomic elements of TMPRSS2 to the ERG gene.
We characterized the function of ERF, as well as its relationship to ERG using CRISPR and shRNA technology to investigate both normal prostate- and patient tumor-derived organoid cultures, as well as existing TMPRSS2-ERG positive models. In both normal prostate and tumor models lacking upregulated ERG, inhibition of the ERF repressor leads to an expansion of the androgen transcriptome, and recapitulates phenotypic features seen with ERG upregulation. Cistromic analysis reveals that ERF occupies androgen-receptor (AR) associated chromatin, overlapping with potential ERG sites. Accordingly, in the presence of the upregulated ERG oncogene, ERF is now unable to bind any AR associated chromatin, and the AR transcriptome is expanded. CRISPR-mediated loss of ERG in TMPRSS2-ERG positive models leads to a halt of tumor cell growth, but concomitant loss of the ERF repressor partially restores cellular proliferation.
We conclude that ERF is an endogenous repressor of androgen signaling in normal prostatic tissue and a potential tumor suppressor in prostate cancer. It occupies chromatin associated with AR-regulated genes and inhibits their transcriptional regulation. Loss of ERF function, either by mutation or more frequently by competition with the TMPRSS2-ERG gene product, leads to an expansion of the androgen transcriptome. Thereby, the ETS positive subtype of prostate cancer, currently defined by an activating ETS fusion event (e.g. TMPRSS2-ERG) should be expanded to encompass genomic loss of a repressive ETS factor.
Citation Format: Rohit Bose, Wassim Abida, Wouter Karthaus, Joshua Armenia, Phillip Iaquinta, John Wongvipat, Michael Doran, Haley Hieronymus, Philip Watson, Patrick Sullivan, Yupu Liang, Nikolaus Schultz, Charles Sawyers. Loss of function mutations of an ETS repressor expand the ETS positive subset of prostate 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 LB-018.
Abstract LB-028: CIRP promotes keratinocytes survival following low-dose UVB irradiation through Stat3-mediated Bag-1/S expression
Authors: Liao Yi , Tang Liling , Wu Shiyong 
Published: July 2016

Abstract
UV induces CIRP expression and subsequent Stat3 activation, but the biological function and mechanism of CIRP and Stat3 in mediating UVB-induced skin carcinogenesis have not been fully elucidated. In this study, we demonstrate that CIRP is elevated in all tested melanoma and non-melanoma skin cancer cell lines; and the expression of CIRP is upregulated in keratinocytes after being irradiated with relatively low dose (&lt;5 mJ/cm2), but not high dose (50 mJ/cm2), UVB acutely and chronically. The increased expression of CIRP, either induced by UVB or through overexpression, leads to resistance of keratinocytes to UVB-induced growth arrest and death; and reduced expression of CIRP by RNA knockdown sensitizes keratinocyte cells to the low dose UVB irradiation. We also demonstrated that CIRP expression is required for the low dose UVB-induced Tyr705-phosphorylation, but not total amount, of Stat3. The p-Stat3 level is correlated with the expression levels of cyclin D1 and VEGF, two known downstream cell growth regulators of Stat3, as well as Bag-1/S, an apoptosis regulator. Inhibition of Stat3 DNA-binding activity by S3I-201 leads to a reduction of the p-Stat3 and Bag-1/S along with growth and survival of keratinocytes post-UVB; and the effect of S3I-201 on the UVB-irradiated cells can be partially inhibited by overexpression of CIRP or Bag-1/S. Furthermore, the overexpression of Bag-1/S can totally inhibit UVB-induced PARP cleavage and caspase 3 activation. The results presented above led us to propose that CIRP-p(705)-Stat3 cascade promotes cell proliferation and survival post-UVB via upregulating the expression of cyclin D1 and Bag-1/S respectively.
Citation Format: Yi Liao, Liling Tang, Shiyong Wu. CIRP promotes keratinocytes survival following low-dose UVB irradiation through Stat3-mediated Bag-1/S expression. [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 LB-028.
Abstract LB-031: Generation of inducible oncogenic chromosomal translocations using CRISPR-Cas9 genomic editing
Authors: Spraggon Lee , Martelotto Luciano , Hmeljak Julija , Slotkin Emily , Wang Lu , Reis-Filho Jorge , Ladanyi Marc 
Published: July 2016

Abstract
Specific, reciprocal chromosomal translocations are found in numerous cancers, typically leading to the formation and expression of fusion genes with oncogenic properties. It has been demonstrated that by inducing double-stranded breaks (DSBs) in genomic DNA, using either zinc fingers nucleases (ZF), transcription activator-like effector nucleases (TALENs), or the CRISPR-Cas9 system, it is possible to faithfully recapitulate such chromosomal translocations in human cell lines.
A potential pitfall is that the induction of the chromosomal translocation generates a constitutively active oncogenic fusion product, which can be detrimental to cell growth or viability in certain heterologous cell types. To overcome these obstacles, we have combined homology directed repair (HDR) with CRISPR-Cas9 genome editing to generate conditionally inducible chromosomal translocations. As proof of principle, we have used this approach to engineer human cell lines to carry the molecular hallmark present in Ewing Sarcoma, the t(11;22)(q24;q12) translocation.
Our approach allows for the de novo generation and capture of the desired chromosomal translocation in the context of a conditional allele. Whole genome sequencing (WGS) and fluorescence in situ hybridization (FISH) confirmed the accuracy of our genomic editing approach, whilst analysis of mRNA and protein levels confirmed the selective inducibility and generation of biologically functional EWSR1-FLI1 fusion oncogene. Therefore, our approach establishes an innovative platform for constructing isogenic and conditionally inducible biologically relevant models for a variety of cancers driven by chromosomal translocations.
Citation Format: Lee Spraggon, Luciano Martelotto, Julija Hmeljak, Emily Slotkin, Lu Wang, Jorge Reis-Filho, Marc Ladanyi. Generation of inducible oncogenic chromosomal translocations using CRISPR-Cas9 genomic editing. [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 LB-031.
Abstract LB-038: Constitutive activation of mTORC1 in endothelial cells leads to the development and progression of lymphangiosarcoma through VEGF autocrine signaling
Authors: Sun Shaogang , Chen Song , Liu Fei , Wu Haige , McHugh Jonathan , Bergin Ingrid , Gupta Anita , Adams Denise , Guan Jun-Lin 
Published: July 2016

Abstract
Angiosarcoma/ lymphangiosarcoma is a rare malignancy with poor prognosis, for which animal models with a defined molecular pathogenesis are lacking. Here, we generated a new mouse model with an inducible endothelial cell specific deletion of Tsc1 to examine the potential role of abnormal activation of mTORC1 signaling in lymphangiosarcoma. We found that loss of Tsc1 increased EC proliferation and retinal angiogenesis in neonates. In adult mice, Tsc1 deletion led to a spectrum of endothelial proliferative lesions, ranging from vascular malformations to vascular tumors. Studies using rapamycin indicated that sustained mTORC1 signaling is required for both the development and maintenance of lymphangiosarcomas. Further analysis showed increased VEGF expression through increased activity of HIF1α and c-Myc transcription factors in tumor cells, and that blockade of autocrine VEGF signaling decreased proliferation of these cells both in vitro and in vivo. Lastly, we found significant correlations between mTORC1 activation and expression of VEGF, HIF1α and c-Myc in human angiosarcoma samples. Together, these studies demonstrate critical mechanisms of aberrant mTORC1 activation in the development of lymphangiosarcoma, and validate Tsc1iΔEC mice as a valuable novel model of lymphangiosarcoma with known molecular underpinnings for further study.
Citation Format: Shaogang Sun, Song Chen, Fei Liu, Haige Wu, Jonathan McHugh, Ingrid Bergin, Anita Gupta, Denise Adams, Jun-Lin Guan. Constitutive activation of mTORC1 in endothelial cells leads to the development and progression of lymphangiosarcoma through VEGF autocrine signaling. [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 LB-038.
Abstract LB-043: Improving rectal cancer therapy using a patient-derived tumor xenograft model
Authors: Camp Ernest R. , Wang Cindy , Hurst Katie , Nogueira Lourdes M. , Findlay Victoria J. 
Published: July 2016

Abstract
Mechanisms of locally advanced rectal cancer (LARC) neoadjuvant chemoradiation resistance are poorly understood. Current research models to study this issue are incomplete and restricted by the limited supply of untreated tissue samples. Patient-derived xenografts (PDX) are commonly developed from surgical specimens and can serve as effective tools to investigate therapy. We previously demonstrated that the SNAI2/ miR-145 signaling axis enhanced the tumor-initiating cell (TIC) and chemotherapy resistance. We developed a unique PDX model from pre-neoadjuvant therapy LARC biopsy samples to study chemoradiation resistance. Further, we hypothesized that TICs isolated from LARC patient-derived xenografts would demonstrated increased SNAI2/ miR-145 signaling.
Methods: Fresh LARC endoscopic biopsy samples were digested using Liberase DH to yield a dissociated single-cell solution. All in vivo experiments consisted of injecting cells with Matrigel subcutaneously into NSG NODSCID/IL2Rgnull immunocompromised mice. Xenograft (Passage 1, P1) single cells were resuspended in ALDEFLUOR assay buffer. ALDEFLUOR and EPCAM positive cells (ALDH+/EPCAM+) were then detected using a flow cytometer to identify the TICs. Using the negative control ALDH inhibitor, DEAB (1.5 μM), identify the ALDH+ cells compared with background. For limited dilution (LD) in vitro spheroid assay, 5000 EPCAM+/ALDH+ and ALDH- cells were cultured in ultra-low attachment plates in cancer stem-cell medium (DMEM-F12; 1X B-27, βEGF, βFGF, 1% penicillin/streptomycin, BSA, heparin, β-mercaptoethanol). For LD in vivo study, EPCAM+ ALDH sorted cells were implanted subcutaneously with Matrigel and closely observed. Droplet Digital PCR was conducted using the QX200 Droplet Digital PCR System. miR-145 PCR was performed using TaqMan MicroRNA Assays (Applied Biosystems) and normalized to RNU6B.
Results: Our LARC PDX model had high outgrowth and engraftment rates of 70 and 85% respectively and maintained critical histologic features. Both LD in vitro and in vivo experiments demonstrated that EPCAM+/ALDH+ cells were highly tumorigenic suggestive of TICs (p&lt;0.05). The ALDH+ population enriched for SNAI2/ miR-145 signaling. miR-145 was inhibited by at least 8.8 fold in the TIC population.
Conclusions: The lack of novel strategies plays a central role in the inability to overcome therapeutic resistance in LARC. Our results demonstrate a novel model to investigate LARC and suggest that a novel miR-145 therapeutic strategy may be able to target the TIC in LARC patients.
Citation Format: Ernest R. Camp, Cindy Wang, Katie Hurst, Lourdes M. Nogueira, Victoria J. Findlay. Improving rectal cancer therapy using a patient-derived tumor xenograft model. [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 LB-043.
Abstract LB-067: Proteomic analysis identifies multi-dimensional deregulated signaling pathways in SCLC lung cancer
Authors: Rikova Klarisa , Hall Ben , Levy Tyler , Possemato Anthony , Aguiar Mike , Beausoleil Sean , Min Ren Jian , Lee Kimberly Lee , Lonning Scott , Comb Michael 
Published: July 2016

Abstract
Lung cancer is the most common type of cancer in the U.S., with 5 yr. survival rates of 18% and 6% for non-small cell lung carcinoma (NSCLC) and small cell lung carcinoma (SCLC) patients, respectively. In spite of success with targeted therapies for 15-20% of patients with NSCLCs, the success is generally short-lived as the tumors become resistant to treatment. In contrast to NSCLC, no successful targeted therapies have been identified in SCLC. Further understanding of the regulatory cell signaling networks for SCLCs, may enable the discovery of new actionable lung cancer drivers.
Posttranslational modifications (PTMs), including phosphorylation, acetylation and methylation, act alone and in combination to regulate protein function, cellular behavior and epigenetics. All three types of PTMs are deregulated in various cancers. In this study we developed a highly quantitative MS/MS approach combining TMT labeling with a number of motif and site-specific antibodies to identify deregulated signaling pathways between tumor and normal specimens. PTM-specific antibodies were used to enrich modified peptides followed by 6-plex TMT mass-spec analyses to quantitatively measure over 15,300 differentially phosphorylated, acetylated, and methylated sites on over 4,600 proteins from 17 SCLC patient tissues and 5 para-normals.
Understanding cell-signaling networks at the intersection of multiple pathways and protein modification systems in SCLC lung cancers leads to the identification of new druggable disease drivers.
Citation Format: Klarisa Rikova, Ben Hall, Tyler Levy, Anthony Possemato, Mike Aguiar, Sean Beausoleil, Jian Min Ren, Kimberly Lee Lee, Scott Lonning, Michael Comb. Proteomic analysis identifies multi-dimensional deregulated signaling pathways in SCLC lung 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 LB-067.
Abstract LB-082: Endoplasmic reticulum stress induces secretion of high mobility group (HMG) proteins and is associated with tumor-infiltrating lymphocytes in triple-negative breast cancer
Authors: Heo Sun-Hee , Park In Ah , Lee Hee Jin , Kim Young-Ae , Gong Gyungyub 
Published: July 2016

Abstract
Purpose: Even though prognostic and predictive significance of tumor-infiltrating lymphocytes (TILs) in triple-negative breast cancer (TNBC) have been demonstrated widely, the cause of TIL influx is not clear. High mobility group (HMG) N1, one of the three subtypes of HMGs which are nucleosome-binding proteins is recently known as a potent alarmin that binds to TLR4 and induces Th1 immune responses. The mechanisms which involve transportation of HMGN1 are not identified. We, in this study, suggest that extracellular secretion of HMGN1 might be associated with influx of TILs and subsequent formation of TLSs, as well as dendritic cell maturation and activation in human TNBC.
Experimental Design: We reviewed the hematoxylin and eosin (H&E)-stained slides of 767 patients with TNBC and evaluated the degree of TILs. We also measured the degree of expression of HMGs (HMGB1 and HMGN1) and several endoplasmic reticulum stress (ERS)-associated molecules (PERK, p-eIF2a, and XBP1) by immunohistochemical (IHC) staining in tissue microarrays of the patients. The hypothesis that HMGN1 migrates from nucleus to cytoplasm and extracellular space as the cell gets variable ER stresses was confirmed by Western blot analyses using human TNBC cell lines and pharmacological ER stress inducers. Results: On IHC staining, high cytoplasmic expression of HMGB1, HMGN1, PERK, p-eIF2a, and XBP1 were identified in 43.1%, 25.7%, 45.9%, 46.9%, and 41.8% of TNBCs, respectively. Cytoplasmic expression of HMGB1 was significantly correlated with cytoplasmic expression of HMGN1, amount of TILs, expression of PERK and XBP1 (p&lt;0.001∼0.039). Cytoplasmic expression of HMGN1 was also significantly correlated with amount of TILs, expression of p-eIF2a and XBP1 (p&lt;0.001∼0.004). Higher nuclear expression of both HMGB1 (p&lt;0.001) and HMGN1 (p&lt;0.001) showed significant association with ER stress. On Western blot analyses using TBNC cell lines, treatment of a ERS inducer resulted in the secretion of HMG proteins to the extracellular space. Conclusions: To the best of our knowledge, it is the first study that elucidated the associations among ERS, extracellular secretion of HMGs, and degree of TILs in TNBCs. Understanding the mechanisms of TIL influx will help to develop effective immunotherapeutic agents for treatment of TNBC.
Citation Format: Sun-Hee Heo, In Ah Park, Hee Jin Lee, Young-Ae Kim, Gyungyub Gong. Endoplasmic reticulum stress induces secretion of high mobility group (HMG) proteins and is associated with tumor-infiltrating lymphocytes in triple-negative breast 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 LB-082.