bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract A26: Modeling the ovarian cancer immune response and tumor microenvironment
Authors: Ozmadenci Duygu , Narayanan Jayanth S. Shankara , Andrew Jacob R. , Barrie Allison M. , Jiang Shulin , Bilir Esra , Bertotto Thomas , White Rebekah R. , Kuchroo Vijay K. , Pachter Jonathan A. , Stupack Dwayne G. , Schlaepfer David D.
Published: June 2020

High-grade serous ovarian cancer (HGSOC) is the leading cause of death from gynecologic malignancies. Many patients initially respond well to surgery followed by chemotherapy, yet ~80% of patients recur with disease that is frequently recalcitrant to chemotherapy. Across a number of chemoresistant cancers, immunotherapies have shown great promise. Correlative studies in patients with HGSOC support a role for immune system in patient outcome. Yet the HGSOC tumor microenvironment (TME) is highly immunosuppressive, which constitutes a major barrier to immunotherapy success. Understanding the molecular signals in HGSOC that promote resistance to chemo- or immunotherapies is required for identification of actionable targets within HGSOC; yet, there are limited models that recapitulate the TME in ovarian cancer. We have generated a new syngeneic C57Bl6 mouse model of ovarian cancer that exhibits genomic copy number gains in KRAS, MYC, and (PTK2) FAK genes (termed KMF) and aggressive malignant phenotypes commonly observed in HGSOC. The KMF TME, like HGSOC, is populated by immunosuppressive myeloid-derived suppressor cells (MDSC) and T-regulatory (Treg) cells but lacks CD8+ T cell infiltration. We find that tumor-associated FAK expression and kinase activity are essential for KMF tumor growth. Mechanistically, by knockout and cell reconstitution approaches, FAK promotes expression of a select group of proteins mediating chemo- and immune-resistance. Inhibiting FAK modulates checkpoint inhibitor protein expression, limits MDSC and Treg recruitment, and enhances CD4 and CD8 T cell infiltration. Pharmacologic FAK inhibition reduced CD112/CD155 expression on KMF cells and, together with anti-TIGIT immunotherapy, significantly increased mouse survival from 28 to 60+ days. The chemoresistant KMF model recapitulates key aspects of the aggressive HGSOC TME including the generation of an immunosuppressive milieu, and may be used as a preclinical model to identify new therapeutic targets for HGSOC.

Citation Format: Duygu Ozmadenci, Jayanth S. Shankara Narayanan, Jacob R. Andrew, Allison M. Barrie, Shulin Jiang, Esra Bilir, Thomas Bertotto, Rebekah R. White, Vijay K. Kuchroo, Jonathan A. Pachter, Dwayne G. Stupack, David D. Schlaepfer. Modeling the ovarian cancer immune response and tumor microenvironment [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr A26.
Abstract A31: Tumor stroma in the development of acquired cancer therapy resistance
Authors: Gomez-Escudero Jesus , Maniati Eleni , Whiting Freddie , Wang Jun , Graham Trevor , Hodivala-Dilke Kairbaan
Published: June 2020

Despite the onset of new treatment strategies, mortality rates for breast cancer are estimated at approximately 600,000 women per year, mostly due to acquired resistance to therapy. Chemotherapy, often combination therapy, includes DNA-damaging agents such as epirubicin, an epimer of doxorubicin. Although chemotherapy has been reported to reduce recurrence rates by 50% over two years, eight-year survival rates are approximately 30% and overall mortality is 20-25%. Studies aiming to overcome resistance to therapy have focused mainly on in vitro malignant cell assays. These have failed to deliver appropriate targets to overcome resistance because they have failed to account for the influence of the tumor microenvironment on chemoresistance. Published evidence indicates that resistance to therapy is not malignant cell-intrinsic, but instead depends on DNA-damaging chemotherapy-induced changes in paracrine signals from endothelial cells. Our current research has established that the doxorubicin treatment acutely affects endothelial cells with long-term effects on tumor cell resistance to therapy in vivo. Endothelial cells are heterogenous, and the effect of DNA damage on endothelial cell evolution and how this regulates malignant cell resistance to therapy is unknown. We have observed that orthotopic murine mammary tumors arising from the same source of primary mammary tumor cells show differential chemotherapy responses. RNA seq analysis of tumors after acute doxorubicin treatment reveal highest levels of differential transcript expression in endothelial cells compared with cancer-associated fibroblasts or malignant cells. In vitro assays show that conditioned media from tumor endothelial cells treated with chemotherapy can protect tumor cells from DNA damage and cell death. Current analysis now focuses on analyzing the complexity of endothelial cell regulation of tumor cell response to chemotherapy and how this could model clonal evolution of tumor cells. We aim to create a chemoresistance stromal evolution signature, to determine the individual components of this and commonalities between cancers and possible drug effects. Thus, our data could change the paradigm of drug resistance and define how stromal compartments regulate acquired resistance.

Citation Format: Jesus Gomez-Escudero, Eleni Maniati, Freddie Whiting, Jun Wang, Trevor Graham, Kairbaan Hodivala-Dilke. Tumor stroma in the development of acquired cancer therapy resistance [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr A31.
Abstract A46: A novel patient-derived approach for preclinical evaluation of predictive imaging biomarkers in early lung cancer
Authors: Koziolek Eva J. , Martin Desiree , Liu Jie , Barrio Jorge R. , Wallace W. Dean , Shackelford David B. , Yanagawa Jane , Dubinett Steven , Scafoglio Claudio
Published: June 2020

Background: Lung cancer is the number one cause of cancer-related death, and lung adenocarcinoma (LUAD) is the most frequent type. Lung screening with computed tomography has allowed detection of early nodules that need diagnostic definition. We have identified the sodium-dependent glucose transporter 2 (SGLT2) as a novel diagnostic and therapeutic target that may aid the identification and the treatment of early LUAD. However, a limitation of these studies is the lack of experimental models of early cancer. Patient-derived xenografts (PDXs) are a reliable tool of translational oncology. However, the establishment of PDXs from early-stage, low-grade LUAD is characterized by low efficiency and extremely long experimental times. To study the predictive value of SGLT2 activity in early LUAD, we have established an alternative model based on a double culture system: 1) implantation of tumor tissue on the chorioallantoic membrane (CAM) of the chicken egg (in ovo system), which can be imaged only 1 week after the patient surgery; 2) growth of tumor spheroids in 3D in vitro culture, to test response to treatments.

Methods: Each PDX of LUAD is divided in two specimens: one for in ovo growth in the CAM assay and one for the 3D culture as tumor spheroids. The CAM xenografts are imaged with two different tracers to characterize glucose uptake: [18F] fluorodeoxyglucose (FDG), to measure GLUT activity, and 4-[18F] fluorodeoxyglucose (Me4FDG), to assess sodium-dependent glucose transport (SGLT). The PD-tumor spheroids are cultured in 96-well plates and used for treatment with SGLT2 inhibitors as well as other drugs.

Results: PET imaging of LUADs with FDG and Me4FDG revealed the presence of both glucose transporters, GLUT1 and SGLT2. Treatment of the tumor spheroids with SGLT2 inhibitors reduced cell viability and caused integrity loss in a dose-dependent manner.

Conclusion: The CAM xenograft model is a useful model for implanting PD tumor fragments and studying glucose metabolism in ovo by PET imaging with very short experimental times. Tumor fragments connect to the chicken embryo vasculature within 3-5 days, so that PD material can be analyzed soon after surgery. The Me4FDG uptake in the CAM system predicts the treatment response of tumor spheroids cultured in vitro from the same PD samples.

Citation Format: Eva J. Koziolek, Desiree Martin, Jie Liu, Jorge R. Barrio, W. Dean Wallace, David B. Shackelford, Jane Yanagawa, Steven Dubinett, Claudio Scafoglio. A novel patient-derived approach for preclinical evaluation of predictive imaging biomarkers in early lung cancer [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr A46.
Abstract A47: In silico organoids: A model for deconvolution of microenvironmental and drug effects on tumor growth
Authors: Rejniak Katarzyna A. , Poonja Sharan , Kingsley Jessica , Mathur Shreya , Chamseddine Ibrahim , Karolak Aleksandra , Markov Dmitry A. , McCawley Lisa J.
Published: June 2020

In vivo tumor microenvironments are heterogeneous in their architecture, cellular contents, metabolic landscape, and extracellular matrix (ECM) composition. Moreover, these microenvironments can undergo temporal and spatial changes. This may alter tumor responses to anticancer therapies. To examine the complex and dynamic changes within tumors and in tumor microenvironments, we developed a computational single cell-based model of the three-dimensional multicellular organotypic cultures: Organoid3D. This model was calibrated to experimental data and reproduced growth dynamics and morphologies of four human breast cell lines: a nontumorigenic epithelial MCF-10A, a mildly tumorigenic MCF-10AT1, and metastatic MCF-10CA-1a and MCF-10CA-1d lines grown in various microenvironmental conditions. By explicitly including the fibril structure of the ECM in the model, we examined how ECM properties promote or suppress the growth of in silico tumor organoids. The quantitative integration of experimental data for organoids exposed to different concentrations of doxorubicin allowed us to derive hypotheses on relative importance of microenvironmental factors and chemotherapeutic treatments on organoid growth. Thus, the in silico organoid model interrogated with experimental data provides a tool for fast and broad hypotheses testing and presents an opportunity to explore experimental conditions beyond what is physically feasible in laboratory experiments.

Citation Format: Katarzyna A. Rejniak, Sharan Poonja, Jessica Kingsley, Shreya Mathur, Ibrahim Chamseddine, Aleksandra Karolak, Dmitry A. Markov, Lisa J. McCawley. In silico organoids: A model for deconvolution of microenvironmental and drug effects on tumor growth [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr A47.
Abstract A52: Deciphering MET-dependent modulation of global cellular responses to DNA damage by quantitative phosphoproteomics reveals Ser1016 as a novel MET phosphosite that regulates cellular response to irradiation
Authors: Koch Jonas P. , Bensimon Ariel , Roth Selina M. , Medo Matúš , Francica Paola , Orlando Eleonora , Riedo Rahel , Gavini Jacopo , Quintin Aurélie , Glück Astrid A. , Stroka Deborah M. , Blaukat Andree , Aebersold Daniel M. , Zimmer Yitzhak , Aebersold Ruedi , Medová Michaela
Published: June 2020

There is emerging evidence that DNA damage response (DDR) intertwines with signaling pathways downstream of oncogenic receptor tyrosine kinases (RTKs). Two complementary phosphoproteomic approaches revealed global networks and identified and validated core phosphosites that participate in a crosstalk between the MET RTK and the DDR, including a newly discovered phosphosite on MET itself, Ser1016. DNA-PK phosphorylates Ser1016, and this phosphorylation is increased following irradiation. Cell lines as well as animal models expressing Ser1016Ala phosphodeficient receptor exhibit greater sensitivity to irradiation. MET Ser1016Ala mutants fail to undergo proper radiation-induced cell cycle arrest by bypassing the G2 checkpoint with a premature entry into mitosis and abnormal mitotic spindles, leading to a lower proliferation rate of Ser1016-deficient cells. Regulation of MET activity through Ser1016 phosphorylation by a DDR core kinase represents a critical event involved in DNA repair signaling through a growth factor receptor that frequently functions as a tumor driver.

Citation Format: Jonas P. Koch, Ariel Bensimon, Selina M. Roth, Matúš Medo, Paola Francica, Eleonora Orlando, Rahel Riedo, Jacopo Gavini, Aurélie Quintin, Astrid A. Glück, Deborah M. Stroka, Andree Blaukat, Daniel M. Aebersold, Yitzhak Zimmer, Ruedi Aebersold, Michaela Medová. Deciphering MET-dependent modulation of global cellular responses to DNA damage by quantitative phosphoproteomics reveals Ser1016 as a novel MET phosphosite that regulates cellular response to irradiation [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr A52.
Abstract B28: Development and validation of a novel organotypic in vitro model of the tumor-lymph-immune interface for predicting immunotherapy resistance
Authors: Zhou Ruolan , Weathered Rachel , Kurtanich Trevin , Mezyk-Kopec Renata , Mansurov Aslan , Hubbell Jeffrey , Swartz Melody A.
Published: June 2020

Tumor-associated lymphatics and their connection to the tumor-draining lymph node (TdLN) play important roles in cancer metastasis as well as in modulating the tumor immune microenvironment. They bathe the TdLN in cytokines, exosomes, antigens, and suppressive factors from the tumor microenvironment (TME) to alter the antitumor immune response. Such interactions are complex and difficult to study in vivo, yet currently they cannot be readily explored in vitro either. To address this need, we developed a novel in vitro model system of the tumor-lympho-immune (TLI) circuit. These in vitro ”avatars,” dubbed TLI-Ivatars, can sustain ex vivo cocultures of tumors and their TdLNs in a parallelized format, within perfused 3D matrices and communicating channels in a flexible manner. The TLI-Ivatar platform has been shown to sustain long-term cultures (> 3 weeks) of a number of tumor cell lines, which form complex architectures reminiscent of actual tumors, as well as of ex vivo tumor tissue. It also supports the function and viability of immune cells (such as T lymphocytes and dendritic cells) and stromal cells (such as lymphatic endothelial cells and fibroblasts). To validate the modeling of the crosstalk between the tumor and TdLN, we demonstrate that TLI-Ivatar can faithfully recapitulate major in vivo immunotherapy responses with the B16 melanoma model, including (i) dampened cytotoxic T-cell function in tumor-conditioned tdLNs, (ii) enhanced tumor invasion to TdLN of lymphangiogenic (and more metastatic) tumors (compared to the TdLN of non-lymphangiogenic tumors), and (iii) immunotherapy potentiation by factors known to enhance immunotherapy efficacy in vivo, such as lymphangiogenic growth factors and matrix-binding immunomodulatory cytokines. Together, these data highlight the potential of TLI-Ivatar for long-term study of the complex tumor-host cell interplay in TME to gain mechanistic insight and pave the way for patient-specific screening of cancer immunotherapy.

Citation Format: Ruolan Zhou, Rachel Weathered, Trevin Kurtanich, Renata Mezyk-Kopec, Aslan Mansurov, Jeffrey Hubbell, Melody A. Swartz. Development and validation of a novel organotypic in vitro model of the tumor-lymph-immune interface for predicting immunotherapy resistance [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr B28.
Abstract B31: A preprocessing filter to improve superparamagnetic relaxometry (SPMR)-based early tumor detection
Authors: Baqri Mehdi , Kandala Sri , Fuentes David
Published: June 2020

The early detection of aggressive forms of ovarian cancer before they metastasize is critical for reducing overall mortality from the disease. Superparamagnetic relaxometry (SPMR) is an imaging technique useful for visualizing early-stage tumors with high sensitivity and specificity. It uses superconducting quantum interference devices (SQUIDs) to detect targeted superparamagnetic iron oxide nanoparticles (SPIONs) that visualize tumors ten times smaller than what conventional imaging techniques can. However, the ultra-sensitivity of SQUIDs increases their risk of distortion due to far-field artifacts. Therefore, a preprocessing filter was developed to mitigate far-field, low-frequency disturbances to SQUID signal acquisition. This is based on the hypothesis that correcting SQUID signal acquisition using a magnetometer for far-field detection will increase the accuracy of SPMR for early tumor detection. The hypothesis was tested in three steps. First, it was shown that the magnetometer (MAG) could specifically detect far-field noise and effectively avoid nanoparticle signatures. Second, high- and low-frequency noise was induced to show that far-field artifacts in the MAG signal correlated with distortions in the SQUID channels. Therefore, a processing filter was developed to parse through and parameterize MAG signal extrema to SQUID signal distortions. A series of further optimization steps included anchoring the MAG signal to respective channels, modeling and subtracting the component of structural (environmental) relaxation, and constraining a general subtraction window. Third, success was measured by the image reconstruction accuracy of sources with various nanoparticle concentrations, using the HSPMR dipole-fitting technique. Overall, the MAG-filter increased reconstruction accuracy more effectively with decreasing nanoparticle signal; accuracy increased the most at very low concentrations (~1ug). Therefore, these preliminary data indicate that the MAG-filter increases SPMR sensitivity for low concentrations representative of very small clusters of cells, typical of early disease stages. Future work will further optimize this initial filter to work uniformly and effectively across different nanoparticle concentrations (and tumor sizes) and translate this technology to highly sensitive early and sparse tumor detection.

Note: This abstract was not presented at the conference.

Citation Format: Mehdi Baqri, Sri Kandala, David Fuentes. A preprocessing filter to improve superparamagnetic relaxometry (SPMR)-based early tumor detection [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr B31.
Abstract IA01: Modeling and understanding tumor biologic mechanisms
Authors: Boutin Adam , Chen Peiwen , Dey Prasenjit , Hou Pingping , Liao Wen-Ting , Lu Xin , Ying Haoqiang , Zhao Di , DePinho Ronald A.
Published: June 2020

This presentation will highlight our use of mouse models to dissect molecular and cellular interactions in the tumor microenvironment, including (i) the illumination of the role of myeloid cells in driving immune suppression in prostate cancer, and the impact of combined MDSC-targeted and immune checkpoint blockade therapies in the treatment of metastatic castration-resistant prostate cancer; (ii) the generation and analysis of oncogenic Kras in an inducible colorectal cancer mouse model, revealing the role of IRF2 in the recruitment of myeloid cells into the tumor microenvironment and informing patient selection for more effective ICB therapy in CRC; (iii) the concept of “synthetic essentiality” (a means by which to target specific tumor-suppressor gene deficiencies in cancer), exemplified by the identification of the role of CHD1 in modulation of the tumor microenvironment in Pten-deficient prostate cancer; (iv) the discovery of a symbiotic interaction between glioma cell (LOX) and macrophage (SPP1) in PTEN-null glioma, as well as macrophage reprogramming in immune suppression in glioblastoma; and (v) the role of KRAS in cancer metabolism, in particular how the tumor microenvironment may support KRAS-directed cancer cell metabolism and provide a nonautonomous mechanism enabling escape from Kras-dependent tumor growth. These illustrative examples provide translational opportunities to improve cancer patient treatment and survival.

Citation Format: Adam Boutin, Peiwen Chen, Prasenjit Dey, Pingping Hou, Wen-Ting Liao, Xin Lu, Haoqiang Ying, Di Zhao, Ronald A. DePinho. Modeling and understanding tumor biologic mechanisms [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr IA01.
Abstract IA09: Tumor organoid cultures as a platform for functional genomics
Authors: Garnett Mathew
Published: June 2020

In an era of genomics-guided precision medicine, there is an increasing need for models that reflect the hallmarks of cancer and the molecular diversity of patient tumors. New cell culturing methods are transforming our ability to derive cell models from healthy and diseased tissues, with increased success rates, and linked to patient genomic and clinical data. I will update on our efforts as part of the Human Cancer Models Initiative (HCMI) to create a new biobank of molecularly annotated tumor organoids as a community resource. Furthermore, I will present how we are beginning to use these organoid cultures for chemical and genetic screens to identify new molecular targets and biomarkers of therapy response. These early studies are laying the foundation for a next-generation tumor organoid functional genomics platform to help guide the development of future precision cancer medicines.

Citation Format: Mathew Garnett. Tumor organoid cultures as a platform for functional genomics [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr IA09.
Abstract IA10: Modeling sensitivity and resistance to systemic therapies in lung cancer
Authors: Politi Katerina A.
Published: June 2020

Targeted therapies have transformed the landscape for the treatment of metastatic lung cancer. Despite their success, targeted therapies are not curative and acquired resistance is a major impediment to cures for patients treated with these therapies. A paradigm for the success of targeted therapies in lung cancer comes from epidermal growth factor receptor (EGFR) mutant lung cancer where mutations in exons encoding the tyrosine kinase domain of EGFR confer sensitivity to tyrosine kinase inhibitors (TKIs), and several TKIs are currently approved for the first-line treatment of EGFR mutant lung cancer. Moreover, there is heterogeneity in the durability and depth of responses between patients and at different metastatic sites within individual patients. Therefore, there is a need to understand the biology of EGFR mutant tumors and identify factors that affect TKI sensitivity. We developed transgenic mouse models of EGFR mutant lung cancer and have used them to study tumor progression and TKI resistance. When we modeled acquired resistance to the TKI osimertinib as a first-line therapy in transgenic mouse models of EGFRL858R-induced lung adenocarcinoma, we found that it is mediated largely through secondary mutations in EGFR—either C797S or L718V/Q or Kras mutations. We also identified a therapeutic approach to prevent the emergence of secondary mutations in EGFR. To determine whether the presence of co-occurring genetic alterations contributes to a more complex spectrum of resistance mechanisms in vivo, we have developed new mouse models to specifically evaluate the consequences of co-occurring tumor suppressor gene alterations on the progression and TKI sensitivity of EGFR mutant tumors. Collectively, our findings highlight how genetically engineered mouse models of lung cancer, including those with complex genotypes, can be leveraged to study tumor progression and drug resistance in vivo.

Citation Format: Katerina A. Politi. Modeling sensitivity and resistance to systemic therapies in lung cancer [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr IA10.
Abstract IA22: Systems approach to rational combination therapy
Authors: Mills Gordon B.
Published: June 2020

Tumors evolve under therapeutic pressure both through rapid epigenomic mechanisms primarily at the protein network level and long-term genomic evolution. The realization of the promise of personalized molecular medicine will require efficient development and implementation of effective combination therapies able to capitalize on or interdict tumor evolution under therapeutic pressure. While we are beginning to develop a series of biomarkers able to predict which patients will benefit from monotherapy, our ability to predict which combination therapies will be active in particular patients is in its infancy. Integration of spatially oriented DNA, RNA, and protein information content as they change under therapeutic pressure has the potential to help identify patients likely to respond to combination therapy.

Therapy resistance can be pre-existing, adaptive, or acquired. Resistance can also occur through a heterogeneity of molecular changes within the tumor and metastases. Adaptive resistance, which is the consequence of activation of homeostatic loops and phylogenetically conserved stress responses, provides a potential therapeutic liability that can be leveraged for rational combinatorial therapy. Thus, a comprehensive analysis of patient tumors before, during, and after treatment should become the standard of practice to enable identification of mechanisms of resistance as well as to allow rapid evolution of patient therapy. Testing these precepts will require the development and implementation of novel biopsy-driven trial designs and CLIA-compliant analytics that can be deployed in real time to allow rapid evolution of therapeutic approaches. We have implemented a suite of biopsy-driven trials linked to deep molecular analysis with the goal of rapid identification of tumor evolution to enable change in therapy to counter tumor evolution as it arises. We have implemented a series of studies based on PARP inhibitors as a backbone with the goal of increasing the depth and duration of response while at the same time extending the population of patients who benefit beyond those with homologous recombination defects. Concurrently, we have a series of n-of-one studies with combinations of FDA-approved drugs. Early data suggest that these approaches have the potential to greatly improve patient outcomes.

Citation Format: Gordon B. Mills. Systems approach to rational combination therapy [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr IA22.
Abstract PHB01: The zebrafish as a mechanical filter: Using zebrafish xenografts to model Ewing sarcoma metastasis in vivo
Authors: Segal Dagan , Chang Bo-Jui , Mazloom-Farsibaf Hanieh , Fiolka Reto , Amatruda James , Danuser Gaudenz
Published: June 2020

Ewing Sarcoma (ES), a pediatric cancer driven by the oncogenic fusion protein EWS-FLI1, recurs or metastasizes in 1 in 3 patients with no clear correlation to accumulation of secondary mutations, raising the possibility that environmental cues may drive metastasis. Previous work in the field has observed distinct cellular morphologies of ES cells in cell culture as a function of EWS-FLI1 level and posited the idea that this may correlate with distinct functional cellular states.

In this work, we use zebrafish xenografts to investigate the effect of variable microenvironments on cellular morphologies of ES cells. We use high resolution light-sheet microscopy to focus on specific recurring seeding sites within the 3-day old zebrafish larvae. We then implement a unique cell-shape classification method to distinguish discrete 3D cellular morphologies in these datasets.

Using this workflow, we observe a variety of cellular morphologies within the fish, including elongated cellular protrusions, blebbing, and rounded cells. We demonstrate that ES cells take on distinct morphological states as a function of the region in which they reside. We find cell proliferation, but not cell death, vary greatly in the different regions, suggesting differences in the functional state of the ES cells. Interestingly, knockdown of EWS-FLI1 in xenografted cells leads to discrete switches between cellular morphologies, but only as a function of seeding site within the fish, suggesting a previously undescribed environmental cue that modulates cellular effects of EWS-FLI1. Overall, the xenograft model for ES in zebrafish embryos can be viewed as a “mechanical filter”, which provides unique, complex 3-dimensional environments to study cell behavior within an organism, while leveraging the advantages of the zebrafish system, namely higher throughput and high resolution in vivo imaging capabilities. This work establishes a pipeline for classification and distinction of morphological states within a living organism, and, more specifically, helps our understanding of cellular plasticity of ES cells in response to microenvironment.

Citation Format: Dagan Segal, Bo-Jui Chang, Hanieh Mazloom-Farsibaf, Reto Fiolka, James Amatruda, Gaudenz Danuser. The zebrafish as a mechanical filter: Using zebrafish xenografts to model Ewing sarcoma metastasis in vivo [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr PHB01.
Abstract PR05: A metabolomics discovery profiling approach identifies an E2F1-associated purine synthesis pathway as a major component of the MET-DNA damage response network
Authors: Poliaková Michaela , Medo Matúš , Koch Jonas , Coggins SiAna , Kim Baek , Aebersold Daniel M. , Zamboni Nicola , Medová Michaela , Zimmer Yitzhak
Published: June 2020

Various lines of investigation support a signaling interphase shared by various receptor tyrosine kinases and the DNA damage response. However, the underlying driving network nodes and their contribution to the maintenance of DNA integrity remain unknown. We used discovery metabolomics combined with transcriptomics to identify changes in global metabolic pathways that are relevant to DNA repair following MET inhibition (METi). METi was associated with formation of γH2AX foci together with significant alterations in major metabolic circuits. Remarkably, 5′-phosphoribosyl-N-formylglycinamide (FGAR), a de novo purine synthesis pathway metabolite, was decreased in MET-dependent cancer models and a METi-related depletion of dNTPs was observed. Likewise, METi instigated the downregulation of critical purine synthesis enzymes including phosphoribosylglycinamide formyltransferase (GART), which is responsible for FGAR synthesis. Genes encoding these enzymes are regulated through the E2F1 transcription factor, whose levels decreased upon METi in MET-driven cells. To validate those findings, a transient E2F1 overexpression was sufficient to prevent MET targeting-dependent dNTPs depletion and the concomitant METi-associated DNA damage in MET-driven tumor cells. These novel observations support the notion that METi-mediated sensitization to DNA-damaging agents commonly used in cancer therapeutics is largely linked to the depletion of critical metabolites used in DNA repair due to downregulation of key metabolic enzymes whose expression is regulated through MET signaling.

This abstract is also being presented as Poster A51.

Citation Format: Michaela Poliaková, Matúš Medo, Jonas Koch, SiAna Coggins, Baek Kim, Daniel M. Aebersold, Nicola Zamboni, Michaela Medová, Yitzhak Zimmer. A metabolomics discovery profiling approach identifies an E2F1-associated purine synthesis pathway as a major component of the MET-DNA damage response network [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr PR05.
Abstract PR06: An in vivo KRAS allelic series reveals distinct phenotypes of common oncogenic variants
Authors: Zafra Maria Paz , Alonso-Curbelo Direna , Goswami Sukanya , Schatoff Emma M , Han Teng , Wilkinson John E. , Dow Lukas E.
Published: June 2020

KRAS is the most frequently mutated oncogene in cancer. Tumor sequencing has revealed a complex spectrum of KRAS mutations across different cancer types, yet there is little understanding of how specific KRAS alterations impact tumor in initiation, progression, or therapy response. Using high-fidelity CRISPR-based engineering, we created an allelic series of new LSL-Kras mutant mice, reflecting codon 12 and 13 mutations that are highly prevalent in lung (KRASG12C), pancreas (KRASG12R), and colon (KRASG13D) cancers. Induction of each mutation in the developing mouse pancreas reveals striking quantitative and qualitative differences in the degree of ductal transformation and premalignant progression. Further, using organoid models we show that KRASG13D mutants respond to EGFR inhibition, while the antiproliferative effect of KRASG12C-selective inhibitors can be overcome by upstream EGFR signaling. Together, these new mouse strains provide an ideal method for investigating KRAS biology in vivo and for developing preclinical precision oncology models of KRAS-mutant pancreas, colon, and lung cancers.

This abstract is also being presented as Poster A41.

Citation Format: Maria Paz Zafra, Direna Alonso-Curbelo, Sukanya Goswami, Emma M Schatoff, Teng Han, John E. Wilkinson, Lukas E. Dow. An in vivo KRAS allelic series reveals distinct phenotypes of common oncogenic variants [abstract]. In: Proceedings of the AACR Special Conference on the Evolving Landscape of Cancer Modeling; 2020 Mar 2-5; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2020;80(11 Suppl):Abstract nr PR06.
Dramatic Response of Pulmonary Sarcomatoid Carcinoma to Nivolumab Combined with Anlotinib: A Case Report
Authors: Jin Caibao , Yang Bin
Published: June 2020

Pulmonary sarcomatoid carcinoma (PSC) is a rare subtype of non-small-cell lung cancer, which is resistant to the conventional chemotherapy and radiotherapy with a poor prognosis. Limited case reports have showed good response to the immunotherapy in PSC patients with high PD-L1 expression generally. Herein, we report a case of rapid recurrence of PSC during postoperative adjuvant chemotherapy in a 62-year-old male ex-smoker. The patient had high PD-L1 expression (tumor proportion score: 90%) and KRAS exon 2 mutation. Nivolumab combined with anlotinib was administered synchronously. Clinical symptoms gradually relieved and response evaluation on imaging revealed a partial response after 8 weeks. This case suggests immunotherapy combined with antiangiogenic agent anlotinib may be a potential promising strategy to treat PSC patients.
Novel Mouse Model for Studying Hemostatic Function of Human Platelets
Authors: Paul David S. , Bergmeier Wolfgang
Published: June 2020

Objective:

Platelets are critical to the formation of a hemostatic plug and the pathogenesis of atherothrombosis. Preclinical animal models, especially the mouse, provide an important platform to assess the efficacy and safety of antiplatelet drugs. However, these studies are limited by inherent differences between human and mouse platelets and the species-selectivity of many drugs. To circumvent these limitations, we developed a new protocol for the adoptive transfer of human platelets into thrombocytopenic nonobese diabetic/severe combined immune deficiency mice, that is, a model where all endogenous platelets are replaced by human platelets in mice accepting xenogeneic tissues.

Approach and Results:

To demonstrate the power of this new model, we visualized and quantified hemostatic plug formation and stability by intravital spinning disk confocal microscopy following laser ablation injury to the saphenous vein. Integrin α
IIb
β
3
-dependent hemostatic platelet plug formation was achieved within ≈30 seconds after laser ablation injury in humanized platelet mice. Pretreatment of mice with standard dual antiplatelet therapy (Aspirin+Ticagrelor) or PAR1 inhibitor, L-003959712 (an analog of vorapaxar), mildly prolonged the bleeding time and significantly reduced platelet adhesion to the site of injury. Consistent with findings from clinical trials, inhibition of PAR1 in combination with dual antiplatelet therapy markedly prolonged bleeding time in humanized platelet mice.

Conclusions:

We propose that this novel mouse model will provide a robust platform to test and predict the safety and efficacy of experimental antiplatelet drugs and to characterize the hemostatic function of synthetic, stored and patient platelets.
LDL Receptor Regulates the Reverse Transport of Macrophage-Derived Unesterified Cholesterol via Concerted Action of the HDL-LDL Axis
Authors: Cedó Lídia , Metso Jari , Santos David , García-León Annabel , Plana Núria , Sabate-Soler Sonia , Rotllan Noemí , Rivas-Urbina Andrea , Méndez-Lara Karen A. , Tondo Mireia , Girona Josefa , Julve Josep , Pallarès Victor , Benitez-Amaro Aleyda , Llorente-Cortes Vicenta , Pérez Antonio , Gómez-Coronado Diego , Ruotsalainen Anna-Kaisa , Levonen Anna-Liisa , Sanchez-Quesada José Luis , Masana Luís , Kovanen Petri T. , Jauhiainen Matti , Lee-Rueckert Miriam , Blanco-Vaca Francisco , Escolà-Gil Joan Carles
Published: June 2020

Rationale:

The HDL (high-density lipoprotein)-mediated stimulation of cellular cholesterol efflux initiates macrophage-specific reverse cholesterol transport (m-RCT), which ends in the fecal excretion of macrophage-derived unesterified cholesterol (UC). Early studies established that LDL (low-density lipoprotein) particles could act as efficient intermediate acceptors of cellular-derived UC, thereby preventing the saturation of HDL particles and facilitating their cholesterol efflux capacity. However, the capacity of LDL to act as a plasma cholesterol reservoir and its potential impact in supporting the m-RCT pathway in vivo both remain unknown.

Objective:

We investigated LDL contributions to the m-RCT pathway in hypercholesterolemic mice.

Methods and Results:

Macrophage cholesterol efflux induced in vitro by LDL added to the culture media either alone or together with HDL or ex vivo by plasma derived from subjects with familial hypercholesterolemia was assessed. In vivo, m-RCT was evaluated in mouse models of hypercholesterolemia that were naturally deficient in CETP (cholesteryl ester transfer protein) and fed a Western-type diet. LDL induced the efflux of radiolabeled UC from cultured macrophages, and, in the simultaneous presence of HDL, a rapid transfer of the radiolabeled UC from HDL to LDL occurred. However, LDL did not exert a synergistic effect on HDL cholesterol efflux capacity in the familial hypercholesterolemia plasma. The m-RCT rates of the LDLr (LDL receptor)-KO (knockout), LDLr-KO/APOB100, and PCSK9 (proprotein convertase subtilisin/kexin type 9)-overexpressing mice were all significantly reduced relative to the wild-type mice. In contrast, m-RCT remained unchanged in HAPOB100 Tg (human APOB100 transgenic) mice with fully functional LDLr, despite increased levels of plasma APO (apolipoprotein)-B–containing lipoproteins.

Conclusions:

Hepatic LDLr plays a critical role in the flow of macrophage-derived UC to feces, while the plasma increase of APOB-containing lipoproteins is unable to stimulate m-RCT. The results indicate that, besides the major HDL-dependent m-RCT pathway via SR-BI (scavenger receptor class B type 1) to the liver, a CETP-independent m-RCT path exists, in which LDL mediates the transfer of cholesterol from macrophages to feces.

Graphical Abstract:

A graphical abstract is available for this article.
Label Adherence of Direct Oral Anticoagulants Dosing and Clinical Outcomes in Patients With Atrial Fibrillation
Authors: Yu Hee Tae , Yang Pil‐Sung , Jang Eunsun , Kim Tae‐Hoon , Uhm Jae‐Sun , Kim Jong‐Youn , Pak Hui‐Nam , Lee Moon‐Hyoung , Lip Gregory Y. H. , Joung Boyoung
Published: June 2020

Background

Dose adjustment of non‐vitamin K antagonist oral anticoagulants (
NOAC
s) is indicated in some patients with atrial fibrillation (
AF
), based on selected patient factors or concomitant medications. We assessed the frequency of label adherence of
NOAC
dosing among
AF
patients and the associations between off‐label
NOAC
dosing and clinical outcomes.

Methods and Results

We evaluated 53 649
AF
patients treated with an
NOAC
using Korean National Health Insurance Service database during the period from 2013 to 2016.
NOAC
doses were classified as either underdosed or overdosed, consistent with Korea Food and Drug Administration labeling. Cox proportional hazards regression was performed to investigate the effectiveness and safety outcomes including stroke or systemic embolism, major bleeding, and all‐cause mortality. Overall, 16 757
NOAC
‐treated patients (31.2%) were underdosed, 4492 were overdosed (8.4%), and 32 400 (60.4%) were dosed appropriately according to drug labeling. Compared with patients with label adherence, those who were underdosed or overdosed were older (aged 71±8 and 75±7 years versus 70±9 years, respectively;
P
<0.001) and had higher
CHA
2
DS
2
‐
VAS
c scores (4.6±1.7 and 5.3±1.7 versus 4.5±1.8, respectively;
P
<0.001).
NOAC
overdosing was associated with increased risk for stroke or systemic embolism (5.76 versus 4.03 events/100 patient‐years,
P
<0.001), major bleeding (4.77 versus 2.94 events/100 patient‐years,
P
<0.001), and all‐cause mortality (5.43 versus 3.05 events/100 patient‐years,
P
<0.001) compared with label‐adherent use.

Conclusions

In real‐world practice, a significant proportion (almost 2 in 5) of
AF
patients received
NOAC
doses inconsistent with drug labeling.
NOAC
overdosing is associated with worse clinical outcomes in Asian
AF
patients.
Antepartum Aspirin Administration Reduces Activin A and Cardiac Global Longitudinal Strain in Preeclamptic Women
Authors: Naseem Heba , Dreixler John , Mueller Ariel , Tung Avery , Dhir Rohin , Chibber Rachna , Fazal Abid , Granger Joey P. , Bakrania Bhavisha A. , deMartelly Victoria , Rana Sarosh , Shahul Sajid
Published: June 2020

Background

Approximately 60% of women have Stage B heart failure 1 year after a preeclamptic delivery. Emerging evidence suggests that the profibrotic growth factor activin A, which has been shown to induce cardiac fibrosis and hypertrophy, is elevated in preeclampsia and may be inhibited by aspirin therapy. We hypothesized that preeclamptic women receiving aspirin would have lower activin A levels and reduced global longitudinal strain (
GLS
), a sensitive measure of cardiac dysfunction, than women who do not receive aspirin. To test our hypothesis, we performed a cohort study of women with preeclampsia or superimposed preeclampsia and compared activin A levels and
GLS
in parturients who did or did not receive aspirin.

Methods and Results

Ninety‐two parturients were enrolled, of whom 25 (27%) received aspirin (81 mg/day) therapy.
GLS
, plasma activin A, and follistatin, which inactivates activin A, were measured. Women receiving aspirin therapy had lower median (interquartile range) levels of activin A (8.17 [3.70, 10.36] versus 12.77 [8.37, 31.25] ng/mL;
P
=0.001) and lower activin/follistatin ratio (0.59 [0.31, 0.93] versus 1.01 [0.64, 2.60]
P
=0.002) than women who did not receive aspirin, which also remained significant after multivariable analysis. Furthermore,
GLS
was worse in patients who did not receive aspirin (−19.84±2.50 versus −17.77±2.60%;
P
=0.03) despite no differences in blood pressure between groups.

Conclusions

Our study suggests that antepartum aspirin therapy reduced serum activin A levels and improved
GLS
in preeclamptic patients, suggesting that aspirin may mitigate the postpartum cardiac dysfunction seen in women with preeclampsia.
From Kings to Monsters: Jewish Perspectives on the Hellenistic and Roman Empires in Sibylline Oracles 3 and 5
Authors: McBay Susannah
Published: June 2020

Both the third and fifth books of the Sibylline Oracles engage with the threat and challenges of the political powers of their day, the Hellenistic and Roman respectively (Sib. Or. 3:657-714; 5:28-34, 155-161, 342-359). Both books also construe these powers as part of the reason for the arrival of God as Divine Warrior to execute judgement. In contrast to Alexandria Frisch, who argued that the Hellenistic Empire was the cause of greater Jewish critique, this article demonstrates that within the Sibylline tradition, the development in use of Jewish combat myth of the Divine Warrior across the two books actually shows the reverse. The texts from Sibylline Oracles 5 escalate the threat of the political enemy, not only depicting the Roman Empire and emperor within the cosmic drama, but as a force of chaos and agent of evil.
New species of Stylopoma (Bryozoa, Cheilostomata) from Bahia State, northeastern Brazil
Authors: RODRIGUES MARIA J.S. , ALMEIDA ANA C.S. , VIEIRA LEANDRO M.
Published: June 2020

At date, seven species of Stylopoma Levinsen, 1909 are reported from the Brazilian coast, five of which are known from Bahia State in the northeastern region. Here we describe four new species of Stylopoma, all from Bahia State: Stylopoma corallinum n. sp., Stylopoma faceluciae n. sp., Stylopoma multiavicularia n. sp. and Stylopoma sinuata n. sp. Unlike the Caribbean species of Stylopoma, that mainly have rounded primary orifice and slit-like sinus, the morphology of the primary orifice of Brazilian taxa, including the new species presented here, is quite variable. In the newly described taxa, the sinus is drop-shaped in S. corallinum n. sp. and S. faceluciae n. sp., U-shaped in S. multiavicularia n. sp. and V-shaped in S. sinuata n. sp. Like congeners from the Caribe, S. corallinum n. sp., S. faceluciae n. sp. and S. multiavicularia n. sp. have avicularia on the surface of the ooecia. Remarks on the morphological characters currently used in Stylopoma taxonomy are provided, including a comparative table of all living species worldwide.
Two new species of the genus Psorosa Zeller, 1846 (Lepidoptera: Pyralidae, Phycitinae) from South Kazakhstan
Authors: TSVETKOV EUGENE
Published: June 2020

Psorosa desaturata sp. nov. and Psorosa pseudoelbursella sp. nov. are described from Karatau Mts. in South Kazakhstan. Male and female genitalia of the species as well as the habitus of the imagines are illustrated. Psorosa desaturata sp. nov. is similar to Psorosa nucleolella (Möschler, 1866) and Psorosa mediterranella Amsel, 1954. Psorosa pseudoelbursella sp. nov. belongs to the Psorosa maraschella Caradja, 1910 species group.
Vertagopus (Collembola, Isotomidae) of Iran and Caucasus
Authors: LAFOORAKI ELHAM YOOSEFI , HAJIZADEH JALIL , ANTIPOVA MARIA , KREMENITSA ALEXANDER , SHAYANMEHR MASOUMEH , POTAPOV MIKHAIL , HOSSEINI REZA
Published: June 2020

The materials on the genus Vertagopus Börner from the Caucasus and Iran are revised. Two new species, V. persicus sp. nov. and V. nunataki sp. nov., are described and fauna of the genus in the Western Asia is commented.