bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 1360: A PARylation biosensor genetic screen to identify novel PARylation targets
Authors: Krastev Dragomir B. , Pettitt Stephen J. , Campbell James , Ashworth Alan , Lord Christopher J. 
Published: August 2018

Abstract
Poly(ADP-ribosylation) (PARylation) is a reversible post-translational protein modification that regulates a number of cellular processes. It is generated by a family of PAR polymerases (PARP), of which PARP1 has recently been exploited as a target in ovarian cancer carrying BRCA1/2 mutations. In addition, tankyrase (PARP5A and B), with its regulation of Wnt signalling, telomeres and the mitotic apparatus, has attracted much effort in the development of targeted therapies. All this necessitates the identification of PARylation targets and their mode of regulation by the modification. Genetically encoded fluorescent biosensor that can report the PARylation state of a target protein has the potential to report the modulation of the PARylation target in living cells. We used PAR-binding PBZ domains fused to a non-fluorescent fragment of a GFP molecule in combination with a protein of interest fused to the complementing fragment of GFP. When this protein is PARylated, it is recognized by the PBZ domain, which brings in proximity the two GFP fragments, and restores the GFP fluorescence. Known targets of PARylation, e.g. TERF1 and AXIN1, showed specific spatial patterns of PARylation validating our approach. In order to identify novel PARylation targets, we have designed a genetic screen based on the biosensor. We introduced the GFP fragment in a transposon, which was randomly integrated in cellular genome, thus generating cellular libraries of thousands of tagged genes. The introduction of the PAR binding probe lead to GFP fluorescence in clones that harbour putative PARylation targets. We developed a next generation sequencing approach to isolate the transposon integration sites and annotated the target genes. Reassuringly, we have identified NPM1, a well-known PARylation target, as a strongly scoring gene. We focused on one of novel identified hits (CTIF). We showed that CTIF is PARylated in vivo in a tankyrase-dependent manner. Furthermore, the biosensor revealed that this PARylation is predominant in a specific cellular compartment surrounding the centrosome. Functional studies have implicated this protein the regulation of the centrosomal satellites. Collectively, we are presenting a new approach to identify PARylated proteins and study their patterns of PARylation and regulation in vivo.
Citation Format: Dragomir B. Krastev, Stephen J. Pettitt, James Campbell, Alan Ashworth, Christopher J. Lord. A PARylation biosensor genetic screen to identify novel PARylation targets [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1360.
Abstract 1365: NR1D1 enhances reactive oxygen species-induced DNA damage by inhibition of PARP1
Authors: Ka Na-Lee , Na Tae-Young , Lee Mi-Ock 
Published: August 2018

Abstract
Breast cancer is the most commonly diagnosed cancer in women worldwide. Cancer cells produce higher levels of intracellular reactive oxygen species (ROS) than their normal counterparts, because of their accelerated metabolism, mitochondrial dysfunction, and antioxidant deficit. The oxidative stress in cancer cells may provide clinical benefits, which can be associated with a better response to anticancer therapies. Therefore, identifying the regulatory pathway of oxidative stress in cancer cells is important in the development of therapeutic targets that enhance sensitivity to ROS-generating anticancer therapies. In this study, we identified that nuclear receptor subfamily 1, group D, member 1 (NR1D1; Rev-erbα) inhibited DNA repair of ROS-induced DNA damage in breast cancer cells. NR1D1 interacted with poly(ADP-ribose) polymerase 1 (PARP1) and subsequently inhibited catalytic activity of PARP1. NR1D1 enhanced accumulation of oxidative DNA damage, which increased sensitivity of breast cancer cells to the ROS-induced cell death. Our findings suggest that NR1D1 may provide better therapeutic options for breast cancer treatment, especially in those patients treated with ROS-inducing chemotherapeutic agents.
Citation Format: Na-Lee Ka, Tae-Young Na, Mi-Ock Lee. NR1D1 enhances reactive oxygen species-induced DNA damage by inhibition of PARP1 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1365.
Abstract 138: PRMT6 promotes lung tumor growth via the modulation of macrophage M2 polarization
Authors: Avasarala Sreedevi , Wu Pei-Ying , Khan Samia Q. , Scoyk Michelle Van , Su Yanlin , David Odile , Gupta Vineet , Bedford Mark T. , Winn Robert A. , Bikkavilli Rama Kamesh 
Published: August 2018

Abstract
Lung cancer kills more people in the United States than any other malignancy. High mortalities are in part due to the diagnosis at an advanced inoperable stage where the 5-year survival is only 4%. Therefore, improving survival will require increased knowledge of genes that drive the complex mechanisms of lung cancer initiation and progression. Emerging data implicate novel roles for protein arginine methylation in lung cancers. In protein arginine methylation, nitrogen/s of arginine can be post-translationally modified via the addition of a methyl group, catalyzed by a class of enzymes, protein arginine methyl transferases (PRMTs). Based on the computational analysis, tissue staining, and immunoblotting we have identified an increased expression of PRMT6 in lung tumors. To test the biologic relevance of PRMT6 in lung tumor development, we employed an inducible lung-targeted PRMT6 gain-of-function (GOF) mouse model. For the first time, we show that lung-targeted overexpression of PRMT6 results in spontaneous lung tumor development. We also observed a robust increase in lung tumors in the PRMT6 GOF mice in response to urethane, a KRas mutagen, and a prototypical model to study lung tumorigenesis. Excitingly, we detected an increase in the number of tumor-associated macrophages (TAMs) in the PRMT6 GOF mice. Further characterization of the TAMs from the PRMT6 GOF mice revealed that they were M2 polarized with immunosuppressive, angiogenesis-enhancing, and tumor-promoting activities. Taken together, these results demonstrate a novel role for PRMT6 in lung tumor development by way of macrophage M2 polarization. Therefore, defining the complete mechanism of PRMT6-mediated macrophage M2 polarization could lead to the development of novel therapeutic strategies to treat lung cancer.
Citation Format: Sreedevi Avasarala, Pei-Ying Wu, Samia Q. Khan, Michelle Van Scoyk, Yanlin Su, Odile David, Vineet Gupta, Mark T. Bedford, Robert A. Winn, Rama Kamesh Bikkavilli. PRMT6 promotes lung tumor growth via the modulation of macrophage M2 polarization [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 138.
Abstract 1380: Towards peptidomimetics to target DOT1L recruitment in MLL-AF9 leukemia
Authors: Grigsby Sierrah Marie , Chase Jennifer , Waas Bridget , Friedman Ann , Du Lei , Yao Aihong , Ropa James , Serio Justin , Muntean Andrew , Maillard Ivan , Sun Haying , Nikolovska-Coleska Zaneta 
Published: August 2018

Abstract
Leukemias harboring rearrangements of mixed-lineage leukemia gene (MLL1) are associated with poor clinical outcomes, and new therapeutic approaches are needed. Rearrangement of the MLL1 gene generates fusion oncoproteins which drive the high expression of the clustered homeobox (HOX) genes and induce leukemic transformation. Genome-wide histone methylation studies have revealed that the abnormal expression of MLL1 fusion target genes is associated with high levels of histone H3 lysine 79 (H3K79) methylation. Recruitment of DOT1L (disruptor of telomeric silencing 1-like), a unique histone methyltransferase that catalyzes methylation of H3K79, proved to be essential for the transforming activity of multiple MLL fusion proteins. We have mapped the binding site to a short segment of 10 amino acids in DOT1L and shown that DOT1L mutants lacking these residues did not support transformation by MLL-AF9. We hypothesized that by targeting the AF9-DOT1L protein-protein interactions (PPIs), we would selectively kill MLL-AF9 cells without effecting DOT1L role in normal hematopoiesis. Using established DOT1Lf/f MLL-AF9 with reintroduced WT-DOT1L, DOT1L missing 10aa AF9-binding domain (D10), DOT1L with a point mutation in the AF9-binding domain (I867A) and enzymatically inactive DOT1L (RCR), we were able to demonstrate that by disrupting the AF9-DOT1L PPIs, although we can inhibit leukemogenesis similarly to enzymatic inhibition, this interaction is not essential for normal hematopoiesis. Based on our initial studies to map the DOT1L interaction site and in conjunction with utilizing reported NMR structures of the AF9-DOT1L complex, we investigated the nature of the interactions and the minimum length of the peptide. Using different natural and unnatural amino acids, we successfully designed a 7mer peptide with KD of 10 nM and 25 nM against AF9 and ENL, respectively, showing similar potency as the originally identified and validated 10mer peptide. These results lay the groundwork for further optimization of the 7mer peptide towards developing DOT1L peptidomimetics with improved potency and cellular activity, to further validate the PPIs between DOT1L and MLL-fusion proteins as a potential therapeutic target for MLL rearranged leukemia.
Citation Format: Sierrah Marie Grigsby, Jennifer Chase, Bridget Waas, Ann Friedman, Lei Du, Aihong Yao, James Ropa, Justin Serio, Andrew Muntean, Ivan Maillard, Haying Sun, Zaneta Nikolovska-Coleska. Towards peptidomimetics to target DOT1L recruitment in MLL-AF9 leukemia [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1380.
Abstract 1396: Pathway-directed DNA demethylation as an epithelial to mesenchymal targeting strategy
Authors: HUANG HAO , Yu Qing , Kandpal Maooj , Davuluri Ramana V. , Matei Daniela 
Published: August 2018

Abstract
It has been proposed that by silencing tumor suppressor genes, DNA methylation plays an important function in cancer initiation and progression. DNA hypomethylating agents are being developed as anti-cancer agents. However, this approach causes unrestricted hypomethylation, which could potentially activate tumor-promoting mechanisms. Therefore a strategy capable of inducing hypomethylation of selected genes is needed. Towards this goal, we designed a strategy to induce demethylation of a coordinated gene program by using Ten-eleven translocation (TET1) dioxygenase, which converts 5 -methylcytosine to 5-hydroxymethylcytosine. We constructed a fusion gene TET1-DBD containing the catalytic domain of TET1 and the DNA binding domain of Snail, the transcription factor that regulates epithelial-to-mesenchymal transition (EMT). We hypothesized that this fusion gene will bind to promoters targeted by Snail, induce hypomethylation, reactivate gene expression, and block EMT. To test this hypothesis, we used TET1-DBD and measured induction of EMT in an ovarian (SKOV3) and breast cancer (MCF10A) model driven by TGF-β. Genome-wide DNA methylation was assessed by Reduced Representation Bisulfite Sequencing (RRBS) to measure the downstream targets of TET1-DBD. TET1-DBD increased mRNA and protein expression levels of E-cadherin in transfected cells and prevented TGF-β induced expression of fibronectin and vimentin in MCF10A and SKOV3 cells. RRBS analysis demonstrated hypomethylation of genes targeted by Snail-DBD. Our results suggest that TET1-DBD selectively binds to and hypomethylates promoters of genes targeted by Snail, resulting in inhibition of the EMT program. We propose a novel approach to induce selective promoter hypomethylation and to block key oncogenic processes by using TET1 fused to a transcription factor “carrier”.
Citation Format: HAO HUANG, Qing Yu, Maooj Kandpal, Ramana V. Davuluri, Daniela Matei. Pathway-directed DNA demethylation as an epithelial to mesenchymal targeting strategy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1396.
Abstract 1402: Silencing of B4GALT1 inversely regulates malignant phenotypes of hepatocellular carcinoma cells
Authors: Chen Po-Da , Chang Ai-An , Wu Yao-Ming , Huang Min-Chuan 
Published: August 2018

Abstract
Identifying molecular targets for hepatocellular carcinoma (HCC) is an urgent need to overcome the treatment failure and death from cancer cell invasion and metastasis. Beta-1,4-galactosyltransferase 1 (B4GALT1) has been documented as the key enzyme in morphogenesis and cellular adhesion, for it adds galactose to N-acetylglucosamine residues of glycoprotein carbohydrate chains; whereas abnormal B4GALT1 expression is associated with tumor progress in many cancers. However, functional roles of B4GALT1 in HCC remains unclear. With clinical correlation, the immunohistochemistry confirmed that lower expression of B4GALT1 in cancer tissue is associated with higher ratio of vascular invasion and worse overall survival. Consistently, stable knockdown of B4GALT1 regarding HCC cell lines promoted cell migration, and invasion; as the overexpressed B4GALT1 inhibited cell migration and invasion of HCC cell lines. Moreover, our data suggested that down-regulated B4GALT1 modified LEL lectin, and interfered hepatocyte growth factor receptor (HGFR), Epidermal growth factor receptor (EGFR), and Axl signaling. Given that, B4GALT1 is sufficient to inversely regulate malignant behaviors of HCC cells with a significant correlation between gene expression and clinical prognosis, implying that B4GALT1 played a crucial role in cancer progress of HCC.
Citation Format: Po-Da Chen, Ai-An Chang, Yao-Ming Wu, Min-Chuan Huang. Silencing of B4GALT1 inversely regulates malignant phenotypes of hepatocellular carcinoma cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1402.
Abstract 1409: p53 negatively regulates keratin 17 expression in oral squamous cell carcinoma
Authors: Enaka Mayu , Nakanishi Masako , Muragaki Yasuteru 
Published: August 2018

Abstract
Background: Cytokeratin 17 (K17) has been shown to promote tumorigenesis and aggressiveness in oral squamous cell carcinomas (OSCCs) and other various carcinomas. Although p53 reportedly induces K17 transcription by irradiation, the correlation between p53 and K17 in OSCCs remains unknown. Methods: Human OSCC cell lines SAS and Ca9-22 were examined by Western blot, immunohistochemistry, ChIP assays, and overexpression of wild-type p53. Biopsy specimens from patients with OSCC were used for immunohistochemistry.Results: Western blot and immunohistochemistry showed that K17 expression negatively correlated with p53 expression. In biopsy specimens, positive staining for K17 was observed in OSCC cells that were negative for p53 in a mutually exclusive manner. SAS cells, which have higher K17 expression and almost negative p53 expression, showed more aggressive characteristics than Ca9-22 cells. A mutation to cause a premature stop codon was identified in the TP53 gene in SAS cells by DNA sequencing, whereas no mutation in the TP53 gene was identified in Ca9-22 cells. In addition, ChIP analysis showed that p53 bound specifically to the promoter region of the K17 gene. Furthermore, overexpression of wild-type p53 suppressed K17 expression in SAS cells. Conclusion: p53 acts as a direct transcriptional repressor of K17 in OSCCs. The interaction between p53 and K17 may regulate aggressiveness of the carcinoma cells.
Citation Format: Mayu Enaka, Masako Nakanishi, Yasuteru Muragaki. p53 negatively regulates keratin 17 expression in oral squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1409.
Abstract 141: HEY1-mediated inhibition of glioma stem cell proliferation is associated with restoration of glioma stem cell division asymmetry and transcriptional repression of PDGFRA
Authors: Bonnin Damian A. Almiron , Sullivan Jaclyn , Israel Mark A. , Havrda Matthew Havrda C. 
Published: August 2018

Abstract
Emerging evidence suggests that deregulation of cell-fate regulatory mechanisms in subpopulations of stem-like tumor cells can contribute to the initiation, progression, and recurrence of glioma. In this study, we report that Hey1 expression suppresses the expansion of oligodendroglial progenitor (OPC)-like glioma stem cells, which are a putative cell of origin for high-grade gliomas. We found that Hey1 expression reduced the proliferation of primary neural progenitor cells isolated from mice without the tumor suppressor Tp53, and OPC-like glioma stem cell cultures isolated from a mouse model of glioma driven by an EGFR gain-of-function mutation and Tp53 loss (v-ErbB/p53-/-). Further analysis of these cultures revealed that Hey1-mediated reductions in proliferation were associated with suppression of self-renewal and a reduced percentage of symmetric cell divisions. Mechanistically, we found that HEY1 directly bound to novel promoter elements and repressed the mRNA expression of a key marker and mitogenic driver of OPCs, the PDGF Receptor A (Pdgfra). Furthermore, Hey1-mediated of Pdgfra expression was associated with inactivation of the canonical PDGF/PDGFRA downstream target, extracellular signal-regulated kinases (ERK), in v-ErbB/p53-/- glioma stem-like cells. Key findings made in the murine system were validated in patient-derived glioma stem-like cells. Moreover, analyzing publicly available databases, we found that the subset of glioma patients with high levels of HEY1 expression had improved survival compared to patients with tumors expressing low levels of HEY1. Further supporting a role for HEY1 in the regulation of the oligodendroglial lineage, ontologic analysis revealed that the subset of patients with high levels of HEY1 expression were also characterized by the expression of gene sets associated with oligodendroglial differentiation. These cellular, molecular and genetic findings provide support for a model in which HEY1 functions to suppress glioma progression by inhibiting the expansion of glioma stem cells.
Citation Format: Damian A. Almiron Bonnin, Jaclyn Sullivan, Mark A. Israel, Matthew Havrda C. Havrda. HEY1-mediated inhibition of glioma stem cell proliferation is associated with restoration of glioma stem cell division asymmetry and transcriptional repression of PDGFRA [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 141.
Abstract 1421: Flexible tools for the development and performance verification of customized target enrichment panels
Authors: Hendrickson Cynthia L. , Mauceli Evan , Barry Andrew , Patel Kruti , Huang Catherine , Adams Scott , Anekella Bharathi 
Published: August 2018

Abstract
Implementation of next generation sequencing for variant identification and discovery presents difficulties both in the selection of genomic loci for inclusion in a panel, as well as the ability to effectively verify the performance of the assay based on the content selected. Balancing the relevance of genomic content with the practical hurdles of developing specific assays necessitates new approaches for the application of next generation sequencing toward precision medicine that are aimed at providing the flexibility of content to efficiently provide data capable of testing fundamental biological hypotheses.
NEBNext Direct Custom Ready Panels overcome these obstacles by enabling the rapid development and deployment of customized target enrichment panels. This offering allows researchers to select from a large library of genes for which baits have been developed and optimized to produce sequencing data with extremely high specificity and coverage uniformity. These panels are effective in targeting a wide range of content, from highly focused, single-gene panels, to comprehensive panels comprised of hundreds of genes.
In a similar approach for the verification and validation of new panels, SeraCare has developed the VariantFlex™ system, which is comprised of a broad library of mutations to develop custom controls and reference materials for NGS-based assays. These biosynthetic constructs contain variants such as SNVs, indel, frameshift and fusion variants that can be used to formulate controls across a range of variant allele frequencies, providing the necessary content and flexibility to verify assay performance.
Here we will present data demonstrating the combined utility of these offerings to assess target enrichment panel performance with a range of genomic content, panel sizes and variant allele frequencies.
Citation Format: Cynthia L. Hendrickson, Evan Mauceli, Andrew Barry, Kruti Patel, Catherine Huang, Scott Adams, Bharathi Anekella. Flexible tools for the development and performance verification of customized target enrichment panels [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 1421.