bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 3642: Combination nanotherapy using the PARP inhibitor talazoparib and cyclin dependent kinase inhibitor dinaciclib
Authors: Baldwin Paige , Orriols Adrienne , Sridhar Srinivas 
Published: August 2019

Abstract
Introduction: PARP inhibitors exploit defects in DNA repair pathways to selectively target cancerous cells. As such, Talazoparib (TLZ), a potent PARP inhibitor, offers a way to target the biology of a number of cancers with DNA repair defects until these tumors develop resistance. PARP inhibitors must be used in combination with other inhibitors or chemotherapeutics to reverse resistance and sensitize non-responsive tumors. Dinaciclib, a potent cyclin dependent kinase (CDK) inhibitor, has been shown to sensitize both BRCA wild-type tumors and PARP inhibitor resistant tumors to PARP inhibition through disruption of homologous recombination. In clinical trials, Talazoparib and Dinaciclib have both demonstrated hematologic toxicities, suggesting a combination of these drugs would result in compounded toxicity, leading to dose reduction and an ineffective combination. Nanoparticle delivery systems offer a means to modify the toxicity profiles of these drugs and enhance the therapeutic window, therefore allowing for effective combination treatment.
Methods: Separate nanoformulations of Talazoparib (NanoTLZ) and Dinaciclib (NanoDCB) were optimized, and pharmacokinetics and pharmacodynamics assessed. Nanoformulations were tested alone and in combination in vitro to ensure NanoDCB could sensitize a model with no known DNA repair defects to NanoTLZ. The combination of the two nanoformulations was then assessed for efficacy and toxicity in orthotopic MDA-MB-231 xenografts.
Results: Robust formulations of NanoTLZ and NanoDCB were developed. Each nanoformulation extended the half-life of the drug it encapsulates. A constant low dose of Dinaciclib sensitized MDA-MB-231 cells to Talazoparib, significantly lowering the IC50 value. As a single agent NanoDCB was more effective in vitro than free Dinaciclib. In vivo, the combination of the two nanoformulations was more effective than either single nanoformulation or the combination of the two free drugs. Assessments of hematologic toxicities are underway, but thus far, there were no signs of gross toxicity in the combination therapy group.
Conclusions: The combination of NanoDCB and NanoTLZ has provided an effective method for sensitizing tumors to PARP inhibition that are otherwise nonresponsive to this therapy. The development of two separate nanoformulations has allowed for tailored dosing. These long-circulating nanoformulations have proven more effective than the free drugs in stabilizing tumor growth and were well tolerated. This work was supported by ARMY/W81XWH-16-1-0731.
Citation Format: Paige Baldwin, Adrienne Orriols, Srinivas Sridhar. Combination nanotherapy using the PARP inhibitor talazoparib and cyclin dependent kinase inhibitor dinaciclib [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3642.
Abstract 3655: Mapping the osteogenic lineage and identification of the cell of origin of osteosarcoma through high-dimensional analysis
Authors: Wang Yifei , Kannan Sankaranarayanan , Zhang Zhongting , Zhang Wendong , Roth Michael , Gill Jonathan B. , Xu Zhaohui , Tian Xiangjun , Wang Jing , Gorlick Richard 
Published: August 2019

Abstract
Osteosarcoma (OS) is the most common primary malignant bone tumor in children and young adults. Neo-adjuvant chemotherapy combined with wide resection increased the 5-year survival rate to 60%-70%. However, treatment and outcome of OS have not changed in several decades. OS is histologically defined by the presence of malignant osteoid, suggesting it could be derived from anywhere in the osteogenic lineage between mesenchymal stem cells (MSC) and mature osteoblasts, but the cell of origin of OS is still undefined. Tracing the cells from which most cancers formed are characterized by its multipotent and/or unipotent stem cell nature. Studies on the cellular origin of tumors from phenotypic lineage-tracking and its derived progeny can reveal tissue-specific tumor-initiating cells. Investigating cell of origin of OS and osteogenic differentiation using developmentally relevant model using MSC to OB differentiation is promising. Here we developed a high-dimensional analytic pipeline using single-cell mass cytometry (CyTOF) and RNA sequencing to discover the unrecognized progenitor-osteoblast populations in the osteogenic lineage. For the data analysis, the population clustering using Flowsom and ConsensusClusterPlus on arcsinh transformed FCS data combined with t-SNE plot visualization shows that combination of CD49f, CD95, CD56, CD117 expression enables the identification and future isolation of the progenitor populations. Also, when comparing OS with the populations from MSC to OB, there are progenitor -osteoblast / mature osteoblast-like populations in tumor cells, but no MSC-like component is found. The expression level of CD56 and CD117 are significantly higher in OS compare to MSC and OB, which warrants future investigation of new therapeutic strategy. Isolation of the progenitor-osteoblast cells, gene expression comparison between OS and these progenitors, validation of their differentiation potential and tumor-initiating capacity is still underway. In this study, we developed a CyTOF based pipeline to discover the progenitor populations in the osteogenic lineage. By comparison of the OS and these progenitor cells, we may be able to unveil the cell of origin and new targeted treatment strategy of OS.
Citation Format: Yifei Wang, Sankaranarayanan Kannan, Zhongting Zhang, Wendong Zhang, Michael Roth, Jonathan B. Gill, Zhaohui Xu, Xiangjun Tian, Jing Wang, Richard Gorlick. Mapping the osteogenic lineage and identification of the cell of origin of osteosarcoma through high-dimensional analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3655.
Abstract 3675: Elucidating the role and function of APOBEC3 DNA deaminases in myeloproliferative neoplasms
Authors: Isquith Jane , Jiang Qingfei , Diep Raymond , Pham Jessica , Holm Frida , Jamieson Catriona 
Published: August 2019

Abstract
The prevalence of upregulated apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3 (APOBEC3) transcripts as well as a distinct mutational signature has been identified and presented extensively in numerous cancer types. Previously, this family of cytidine deaminases has been studied in innate immunity, as they are active in the conversion of cytosine to uracil to restrict retroviral replication. Recent studies employing whole exome sequencing of multiple cancer types have shown a significant increase in both APOBEC3 transcript level as well as an increase in mutations indicated as a result of APOBEC3 driven mutagenesis. However, the expression and role of these enzymes in cancer initiation and progression as well as the mechanisms by which the APOBEC3 enzymes elicit a response in the cancer microenvironment remains unknown, especially in hematopoietic malignancies. Here, we elucidate the APOBEC3 mutation phenotype in Myeloproliferative Neoplasms (MPNs) as well as the naïve cell populations of CD34+ cord blood and normal aged samples. Through RNA sequencing we have found a cell type and context specific nature of these enzymes, notably the upregulation of APOBEC3G (A3G) in the Myelofibrosis (MF) stem and progenitor cell population as compared to normal aged counterparts. There is also significant differential expression of APOBEC3C (A3C), APOBEC3D (A3D), and APOBEC3F (A3F) in MF disease states compared to normal controls. By cloning the APOBEC3 enzymes into lentiviral expression vectors, we can now study the physiological effects of changes in APOBEC3 transcript level in relation to the known changes in expression seen in many cancers, focusing on the upregulation of A3G through lentiviral overexpression. Using these techniques, we will also elucidate the mutation signature of APOBEC3G in CD34+ cord blood as compared to the known mutagenesis pattern derived from the editing signature of APOBEC3B. Upon APOBEC3G overexpression we can connect the prevalence and proposed activity of the enzymes to the physiological deregulation present in hematopoietic malignancies. We have found that A3G induces a proliferative burst in normal CD34+ cord blood, which leads us to study the effects of APOBEC3 upregulation in regards to proliferation, differentiation and self-renewal in normal and malignant cells as well as their potential function in disease initiation and progression in MPNs.
Citation Format: Jane Isquith, Qingfei Jiang, Raymond Diep, Jessica Pham, Frida Holm, Catriona Jamieson. Elucidating the role and function of APOBEC3 DNA deaminases in myeloproliferative neoplasms [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3675.
Abstract 369: Antitumor activity of M4344, a potent and selective ATR inhibitor, in monotherapy and combination therapy
Authors: Zenke Frank T. , Zimmermann Astrid , Dahmen Heike , Elenbaas Brian , Pollard John , Reaper Philip , Bagrodia S , Spilker M E. , Amendt C , Blaukat Andree 
Published: August 2019

Abstract
The protein kinase ataxia telangiectasia mutated and Rad3-related ATR is one of the key mediators of the DNA damage response. ATR is recruited to regions of single-stranded DNA, which most commonly arise during replication stress (RS). RS occurs during S-phase when the cell’s DNA replication machinery encounters problems such as unresolved DNA lesions. In addition, treatment of cells with DNA-damaging agents can lead to RS as cells progress to S-phase without resolving damage incurred by such agents. Elevated levels of RS are evident in some cancer cells, even in the absence of a DNA-damaging agent resulting from expression of oncogenes that drive dysregulated replication, a hypoxic environment, or from defects in other repair pathways. RS in cancer cells can drive reliance on ATR for survival and, accordingly, ATR inhibitors may have benefit as monotherapy. M4344 was determined to be an adenosine triphosphate (ATP)-competitive, highly potent, and tight-binding inhibitor of ATR with a Ki of &lt; 150 pM. Minimal inhibitory activity was observed against a large panel of unrelated protein kinases, with 308 of 312 kinases tested having a measured Ki corresponding to more than 100-fold selectivity. M4344 potently inhibits ATR-driven phosphorylated checkpoint kinase-1 (P-Chk1) phosphorylation with an IC50 of 8 nM. Profiling on a selected set of cancer cell lines showed synergy with several types of DNA damaging chemotherapeutics as well as PARP1/2 and CHK1 inhibitors. In monotherapy efficacy studies M4344 showed tumor stasis to regression in tumor models with alternative lengthening of telomeres (ALT). In combination with PARP inhibitors, tumor regression could be observed in triple-negative breast cancer xenograft models. A dose-escalation phase 1 study in patients with advanced solid tumors is currently ongoing.
Citation Format: Frank T. Zenke, Astrid Zimmermann, Heike Dahmen, Brian Elenbaas, John Pollard, Philip Reaper, S Bagrodia, M E. Spilker, C Amendt, Andree Blaukat. Antitumor activity of M4344, a potent and selective ATR inhibitor, in monotherapy and combination therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 369.
Abstract 3693: GLIS1 can replace MYC to generate induced pluripotent stem cells from ovarian cancer cells
Authors: Bindhya S , Sidhanth C , Krishnapriya S , Nagare R P. , Garg M , Ganesan T S. 
Published: August 2019

Abstract
Ovarian cancer is the most common cause of mortality among gynecological cancers, despite advances in treatment. Recurrence is common and is due to development of drug resistance. One of the reasons for drug resistance is the persistence of cancer stem cells. To understand the role of CSCs, it is essential to capture and propagate cells continuously in culture. Reprogramming cancer cells to induced pluripotent stem cells (iPSCs) is an approach to achieve this. An ovarian cancer cell line, PEO4 (high grade serous adenocarcinoma), was initially reprogrammed into iPSCs using the classical four factors OCT4, SOX2, KLF4 and MYC (OSKM) using STEMCCA by lentivirus transduction. Embryonic stem cell (ESC)-like bodies appeared between 8 to 15 days post-transduction. Morphology of the colonies resembled that of ESC colonies with defined border and tightly-packed cells. Two individual clones were further characterized. The reprogrammed PEO4-OSKM-iPSCs expressed alkaline phosphatase and pluripotency markers, NANOG, OCT4, SSEA4, TRA-1-60 and TRA-1-81 by immunofluorescence. Further, reverse-transcriptase-polymerase chain reaction (RT-PCR) analysis showed expression of the pluripotency markers NANOG, SOX2, OCT4, TERT, NESTIN, DMNT, DPPA4 in PEO4-OSKM-iPSC which were absent in the parental PEO4 cells. PEO4-OSKM-iPSC cells could be differentiated in vitro with appropriate growth factors into ectodermal, mesodermal and endodermal lineages. MYC was replaced with GLIS1 in the lentiviral cassette and PEO4 cells were able to be transformed to iPSCs. The transfection efficiency was two fold better with OCT4-SOX2-KLF4-GLIS1 with larger colonies. Individual iPSC colonies expressed all pluripotency markers and were able to differentiate into all 3 lineages. Characterization of iPSC cells for expression of cell surface markers specific for serous adenocarcinoma, showed that CD133, EPHA1, CD44 and LGR5 were expressed. Cell viability assays demonstrated that IC50 of cisplatin in parental PEO4 cells (15uM) was less as compared to iPSC cells (32uM) (p&lt;0.03) and similarly, IC50 of paclitaxel was less in parental PEO4 (17 uM) as compared to iPSC cells (27 uM) (p&lt;0.02). These results demonstrate for the first time that an ovarian cancer cell line derived from a patient with high grade serous adenocarcinoma can be reprogrammed. Further, GLIS1 can successfully replace MYC as a transcription factor to generate induced pluripotent stem cells.
Citation Format: S Bindhya, C Sidhanth, S Krishnapriya, R P. Nagare, M Garg, T S. Ganesan. GLIS1 can replace MYC to generate induced pluripotent stem cells from ovarian cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3693.
Abstract 370: The role of DLX1 as a biomarker and novel target in poor prognostic prostate cancer
Authors: Forsythe Nicholas , McKinney Cathal , McCabe Nuala , Kennedy Richard D. 
Published: August 2019

Abstract
Introduction: Previous work from our lab has identified a molecularly distinct subgroup of primary prostate cancers with biology similar to metastatic prostate cancers. These “met-like” cancers can be identified by a 70 gene classifier and are statistically more likely to result in distant metastases than their “non-met like” counterparts. This study aimed to identify exploitable biology common to both “met-like” primary tumours and metastatic prostate cancer.
Experimental procedures: Differential gene expression and Ingenuity pathway analysis (IPA) was used to identify nodal genes upregulated in both “met-like” primary prostate cancers and metastatic prostate cancers. siRNA screening was performed on 40 nodal genes in a panel of normal, primary and metastatic prostate cancers. Cell viability was assessed using cell titer-glo luminescent Assay. Relative levels of apoptosis were assessed using PARP, caspase-8 and caspase-3 cleavage Western Blots. siRNA mediated knockdowns were confirmed by Western Blot and rtPCR.
Results: We have identified upregulation of the homeobox transcription factor DLX1 in “met-like” primary prostate cancers and metastatic prostate cancers. High levels of DLX1 expression were found to be independently predicative of biochemical recurrence and metastatic disease in primary prostate cancers. DLX1 knockdown resulted in significantly decreased cell viability in primary and metastatic prostate cancer cell lines with minimal reduction of viability in normal prostate cells. Additionally DLX1 knockdown was shown to result in increased PARP, caspase-8 and caspase-3 cleavage providing evidence of apoptotic cell death. Furthermore knockdown of DLX1 resulted in significantly increased transcript levels of the pro-apoptotic BH3 protein BIK, suggesting its involvement in the observed apoptotic cell death.
Conclusion: DLX1 has previously been identified as a marker of prostate cancer metastasis with increased expression being observed in both primary and metastatic prostate cancers. However we have observed increased DLX1 expression in a subset of primary prostate cancers that developed metastatic diseased compared to primary tumors that did not metastasise. The elucidation of apoptotic mechanisms following DLX1 knockdown may uncover potential exploitable biology that may be used for the treatment of prostate cancer.
Citation Format: Nicholas Forsythe, Cathal McKinney, Nuala McCabe, Richard D. Kennedy. The role of DLX1 as a biomarker and novel target in poor prognostic prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 370.
Abstract 3706: The CRISPR-Cas9 minipig: A transgenic toolbox pig to produce specific genome editing in designated tissues
Authors: Berthelsen Martin F. , Riedel Maria , Vendelbo Mikkel H. , Alstrup Aage K. , Dagnæs-Hansen Frederik , Luo Yonglun , Møller Simone S. , Callesen Henrik , Jakobsen Jannik E. , Thomsen Martin K. 
Published: August 2019

Abstract
The aim of the project is to generate a toolbox pig model. This is being done because the pig probably is the best non-primate model in translational medicine. Unfortunately, pig models have proven difficult to produce. The two main complications have been the cloning of viable pigs and that just a few genes are altered, which often is not sufficient to induce the desired disease. Especially, models based on multiple genetic modifications of the pig genome, e.g. cancer, are challenging to generate. This was changed with the development of the CRISPR-Cas9 technology, which made it possible to perform multiple in vivo gene editing.
We have cloned an inducible Cas9 expressing minipig and have obtained healthy F1 offspring. Activation of the Cas9 expression is attained by transduction with adeno-associated virus that delivers both the recombinase and the guide RNA to the designated tissue. This design provides spatial and temporal control of the activation. The Cas9 expression is mediated by a ubiquitous promotor, which also co-expresses fluorescent proteins for expression analysis. Transgenic Cas9 expression is observed in all major organs with strong expression in the epithelia, muscles and hepatocytes. Successful in vitro gene editing has been conducted in primary keratinocytes and fibroblast obtained from the transgenic pigs, which confirms the genetic design.
By delivery of our construct by adeno-associated virus to the skin of the pigs, In vivo activation of the transgenic construct has been achieved. To validate the model, lung cancer has been induced in nine pigs by alteration a panel of cancer related genes including STK11, TP53, PTEN, and KRAS, all key drivers of human lung cancer. To obtain the constitutive active KRAS-G12D isoform of the KRAS oncogene a repair template was supplied. The pigs are being followed by PET/CT scanning in combination with 18F-FDG as a tracer. Preliminary data indicates abnormalities/cancer initiation in the pigs eight months after induction.
In conclusion, an inducible Cas9 expressing minipig allows rapid gene editing to study different scenarios of human cancer in a pig model. The development of the Cas9 pig will extend the variety of pig disease models, both to generate a model of lung cancer as proposed but also models for other cancers.
Citation Format: Martin F. Berthelsen, Maria Riedel, Mikkel H. Vendelbo, Aage K. Alstrup, Frederik Dagnæs-Hansen, Yonglun Luo, Simone S. Møller, Henrik Callesen, Jannik E. Jakobsen, Martin K. Thomsen. The CRISPR-Cas9 minipig: A transgenic toolbox pig to produce specific genome editing in designated tissues [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3706.
Abstract 3713: Strong expression of EZH2 and H3K27me3 is associated with poor survival time in small cell lung cancer
Authors: Fernandes Ana Paula , Alves Rita deCassia S , Watte Guilherme , Kunze Philipp , Roehe Adriana Vial , Schneider-Stock Regine 
Published: August 2019

Abstract
BACKGROUND: Small-cell lung cancer (SCLC) is a highly aggressive neoplasm, characterized by early development of metastasis and very poor clinical outcome. The therapeutic possibilities are limited and poorly changed over the past three decades. Enhancer of zeste homolog 2 (EZH2) is a member of the polycomb repressive complex 2. It is involved in epigenetic gene silencing through the trimethylation of H3K27 and it has been identified as a biomarker of aggressive and highly proliferating tumors, emerging as a potential target for cancer therapy.
OBJECTIVE: We aimed to correlate the expression profile of the EZH2 and H3K27me3 proteins in tumor tissues of non-treated SCLC patients with patient's outcome.
METHODS: EZH2 and H3K27me3 expression were analyzed by immunohistochemistry in 48 SCLC tumor biopsies. The expression of the markers was quantified in a semi quantitative way and correlated with clinic pathological factors and patients overall survival. To mimic an EZH2 loss, H209 SCLC cells were treated with an EZH2 inhibitor for 48h and the in vivo growth pattern was investigated in the chorioallantoic membrane (CAM) assay.
RESULTS: All patients died within one year after diagnosis. There was a heterogeneous expression pattern for EZH2 and H3K27me3. Strong expression of EZH2 and H3K27me3 was observed in appr. 50% of the patients. The Kaplan Meier curve showed a significant association of high expression pattern of EZH2 and shorter overall patient survival time after 12 and 25 weeks of follow up, respectively (p=0.030; p=0.014) Different markers of tumor aggressiveness after EZH2 inhibition were investigated in the CAM model.
CONCLUSION: Strong EZH2 and H3K27me3 expression in non-treated SCLC patients was related to worse prognosis. EZH2 inhibitors should be considered in future trials for SCLC.
Citation Format: Ana Paula Fernandes, Rita deCassia S Alves, Guilherme Watte, Philipp Kunze, Adriana Vial Roehe, Regine Schneider-Stock. Strong expression of EZH2 and H3K27me3 is associated with poor survival time in small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3713.