bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 6289: Phenotypic screening of small molecules for novel immuno-oncology potential using BioMAP® Early Screening Services
Authors: O'Mahony Alison , Denker Sheryl P. , Velichko Sharlene 
Published: September 2020

Abstract
Approved immuno-oncology (IO) drugs that have expanded the arsenal of available treatment options for recalcitrant cancers include antibodies to PD-(L)1 checkpoints–a relatively new class of immunotherapies. While the clinical success reported for these drugs is compelling, efficacy is limited to a small cohort of patients. The need for more IO therapeutic options has prompted the pursuit of next-generation candidates that can achieve better patient outcomes. One approach is to screen compounds for novel targets that elicit an immunorestorative response within the tumor microenvironment (TME), consistent with approved IO drugs. Ideally, a small molecule therapeutic would represent a distinct advantage over existing biologics, both in terms of administration as well as ability to optimize chemistry. In order to efficiently identify molecules with IO potential, a high throughput, physiologically relevant screening approach that recapitulates the complexity of the TME is needed. BioMAP Oncology systems are co-cultures of human primary cell types (endothelial cells, fibroblasts, and PBMCs) and cancer cells that model immune suppressed TME biology. Compounds can be screened in these in vitro TME models to look for impacts on protein biomarkers relevant for immune responses, inflammation, matrix modulation and for impacts on cancer cells. These systems were validated for immune restorative activities using anti PD-(L)1 therapeutics such as pembrolizumab, nivolumab, and durvalumab. Specifically, increased pro-inflammatory cytokine levels served as hallmark activities indicating a reversal of the immune suppressive influence of the cancer cell. In one of the BioMAP Oncology systems, we screened a library of 72 compounds targeting different molecules, the vast majority of which had not previously been identified as potential immuno-oncology candidates. Several small molecules that increased one or more cytokines were identified, indicating immune restorative potential. Other small molecules inhibited immune responses and/or demonstrated anti-inflammatory activities. Additionally, modulation of matrix biomarkers on tissue and tumor cells indicate impacts on distinct compartments of the TME. This approach using human cell-based in vitro TME models represents a rapid and cost-effective manner to rapidly screen libraries of small molecules (both novel and repurposed) for immuno-oncology potential.
Citation Format: Alison O'Mahony, Sheryl P. Denker, Sharlene Velichko. Phenotypic screening of small molecules for novel immuno-oncology potential using BioMAP® Early Screening Services [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6289.
Abstract 6303: CRISPR/Cas9 RNP mediated efficient gene editing in hard-to-transfect cells
Authors: Li Peixue , Li Zhao , Lin Qing 
Published: September 2020

Abstract
It has been challenging for efficient gene editing in cells which are hard to transfect, such as stem cells and primary T cells. Typical sgRNA and Cas9 intracellular delivery techniques are limited by their reliance on cell type and exogenous materials as well as their toxic effects on cells (for example, electroporation) or packaging capacity limitation by viral vectors. Here we established an effective approach for gene editing in different cell types and achieved successful genome editing with CRISPR RNP electroporation. Also, high efficient double knockout mutations could be obtained by electroporation of multiple sgRNAs at one shot. Furthermore, this method also could reduce the exposure time to Cas9 nuclease which may cause potential off-target effects. With the advantages of broad applicability across different cell types, particularly hard-to-transfect cells, and flexibility of application, these methods could potentially enable the development of the stem cell or T cell based therapies.
Citation Format: Peixue Li, Zhao Li, Qing Lin. CRISPR/Cas9 RNP mediated efficient gene editing in hard-to-transfect cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6303.
Abstract 6307: In vivo drug screening platform accelerates anti-hCD40 antibody drug discovery
Authors: Yang Yi , Li Zhihong , Zhu Yu , Xie Jingshu , Chen Yunyun 
Published: September 2020

Abstract
The CD40 (also known as TNFRSF5) and its ligand CD40L (also known as CD154) belong to the TNF/TNFR family. CD40 is expressed on antigen presenting cells (APCs), including B cell, monocytes, macrophages and dendritic cells. CD40-CD40L is a pair of costimulatory molecules that, after interacting at the cell surface, promotes intracellular signaling by recruiting TNFR-associated factor (TRAF) in the cytosol, thereby activating multiple downstream signaling pathways. Therapeutic targeting of CD40 by agonistic monoclonal antibodies (mAbs) aims to activate CD40+ APCs to effectively boost tumor-specific cytotoxic T cells to eliminate tumor cells. In principle it has the advantage of greater tumor specificity over other T cell activating approaches, such as checkpoint inhibition or indiscriminate T cell activation.
We are interested in developing a novel immune checkpoint monoclonal antibody that targets CD40 and can treat cancer patients. Using Biocytogen's antibody research platform, dozens of candidate antibodies were obtained by classical hybridoma technology as well as high-throughput flow cytometry screening. Next, these murine antibodies were screened directly in humanized mouse models (B-hCD40) bearing a syngeneic cancer cell line. We discovered candidates that have potent anti-tumor activity in vivo. These candidate antibodies were further humanized, and we found an antibody called YH003 with potent antitumor activity in the MC38 tumor model. Fortunately, YH003 was able to inhibit tumor growth in combination with Pembrolizumab in the double humanized model of h-CD40 and h-PD1 bearing a syngeneic B16F10 cancer cell line. In vitro studies demonstrated that YH003 bound specifically and potently to human and monkey CD40 proteins, we used cynomolgus monkeys to further explore the safety evaluation. In conclusion, we use Biocytogen's in vivo drug screening platform to obtain more novel CD40 antibodies with anti-tumor activity in addition to YH003, accelerating the progress of preclinical antibody discovery.
Citation Format: Yi Yang, Zhihong Li, Yu Zhu, Jingshu Xie, Yunyun Chen. In vivo drug screening platform accelerates anti-hCD40 antibody drug discovery [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6307.
Abstract 6321: BEND3 modulates sensitivity to the UBA1 inhibitor TAK-243 by regulating expression of the multidrug transporter BCRP
Authors: Barghout Samir H. , Aman Ahmed , Blatman Zachary , Arevalo Karen , Thomas Geethu , MacLean Neil , Wang Xiaoming , Hurren Rose , Ketela Troy , Abohawya Moustafa , Kiyota Taira , Al-Awar Rima , Schimmer Aaron D. 
Published: September 2020

Abstract
TAK-243 (MLN7243) is a first-in-class inhibitor of the ubiquitin-activating enzyme (UBA1) that catalyzes the first step in the ubiquitylation cascade whereby proteins are tagged with mono- or poly-ubiquitin to induce their degradation or modify their functions. Based on its preclinical efficacy and tolerability, TAK-243 has entered phase 1 clinical trials in advanced malignancies. However, the determinants of sensitivity to TAK-243 remain largely unknown. Therefore, we conducted a positive-selection, genome-wide CRISPR/Cas9 knockout screen in OCI-AML2 cells followed by selection with lethal TAK-243 concentrations to identify genes essential for TAK-243 action. We identified BEN domain-containing protein 3 (BEND3), a transcriptional repressor and a regulator of chromatin organization, as the top gene whose knockout conferred resistance to TAK-243 (FDR = 0.0012). BEND3-targeting gRNAs were enriched up to 10,000-fold after selection with the drug. To validate the screen results, we independently knocked out BEND3 in OCI-AML2 cells and confirmed the resistance phenotype. In vivo, tumors of BEND3-knockout cells were resistant to TAK243 (20 mg/kg twice weekly) as opposed to control tumors that showed dramatic reductions in tumor growth rate. As assessed by immunoblotting, BEND3 knockout dampened TAK-243 effects on ubiquitylation, proteotoxic stress and DNA damage response. Mechanistically, BEND3 knockout upregulated the ABC efflux transporter breast cancer resistance protein (BCRP; ABCG2), and decreased intracellular levels of TAK-243. It also conferred partial cross-resistance to pevonedistat and TAK-981–related selective inhibitors of the NEDD8-activating enzyme (NAE) and the SUMO-activating enzyme (SAE), respectively, as well as known substrates of BCRP (mitoxantrone and doxorubicin). Finally, TAK-243 sensitivity strongly correlated with BCRP expression in a panel of 30 cancer cell lines of different origin, and chemical inhibition of BCRP but not P-gp sensitized intrinsically resistant high-BCRP cells to TAK-243. Thus, our data demonstrate that BEND3 regulates the expression of BCRP for which TAK-243 is a substrate. Moreover, BCRP expression could serve as a predictor of TAK-243 sensitivity.
Citation Format: Samir H. Barghout, Ahmed Aman, Zachary Blatman, Karen Arevalo, Geethu Thomas, Neil MacLean, Xiaoming Wang, Rose Hurren, Troy Ketela, Moustafa Abohawya, Taira Kiyota, Rima Al-Awar, Aaron D. Schimmer. BEND3 modulates sensitivity to the UBA1 inhibitor TAK-243 by regulating expression of the multidrug transporter BCRP [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6321.
Abstract 6330: DPP4 modulates ACSL4 to promote lipid peroxidation and regulate ferroptosis in pancreatic cancer
Authors: Zhou Xiang , Wang Weiming , Zhang Baofu , Lin Zixia , Wang Yi , Chen Gang 
Published: September 2020

Abstract
BACKGROUND and AIMS: Pancreatic ductal adenocarcinoma (PDAC) is one of the highest mortality rate cancers with almost no curative chemotherapeutic treatment. Ferroptosis is a recently recognized regulated necrotic cell death and that has emerged to play an important role in cancer biology. Recent discoveries have highlighted the important role of Dipeptidyl-peptidase-4 (DPP4) in TP53-deficient cancer cells. PDAC Patients with a lower DPP4 level have a poorer postoperative survival. We investigated whether DPP4 contributes to ferroptosis in pancreatic cancer.
METHODS: DPP4 expression status was evaluated in PDAC tissues using tissue chip immunohistochemistry. The effects of DPP4 re-expression or knockdown on cell proliferation, the cell cycle and energy metabolism were determined. DPP4 interacting protein was identified by mass spectrometry and DPP4-related cancer pathways by RNA-seq analyses. The clinical impact of DPP4 in driving ferroptosis and enhancing gemcitabine sensitivity was assessed in patient-derived xenograft tumours (PDX), subcutaneous, and DPP4 knock-down (KD) or knock-in (KI) mice orthotopic xenograft models of PDAC.
RESULTS: DPP4 was commonly low expression in PDAC. DPP4 significantly inhibited cell proliferation by causing G1-S cell cycle arrest, inhibiting energy metabolism and promoting erastin-induced ferroptosis in vitro, and suppressed xenograft tumour growth in both subcutaneous and orthotopic xenograft mouse models (both p&lt;0.001). Mechanistically, DPP4 facilitated ferroptosis by binding ACSL4 and the DPP4-ACSL4 interaction stabilized ACSL4 by inhibiting its ubiquitin-mediated degradation, and subsequent lipid peroxidation. This interaction inactivated their downstream key elements of NF2-YAP signalling cascades. Importantly, the DPP4-ACSL4 pathway dictated ferroptosis sensitivity and promoted the anticancer activity of gemcitabine. Activating of the DPP4-ACSL4 pathway enhanced gemcitabine sensitivity by disinhibiting ferroptosis in vitro and in PDX, subcutaneous, and DPP4 KD or KI orthotopic xenograft models of PDAC.
CONCLUSIONS: Collectively, these findings identify a novel role of DPP4 in ferroptosis and suggest a potential therapeutic strategy for overcoming gemcitabine resistance.
Citation Format: Xiang Zhou, Weiming Wang, Baofu Zhang, Zixia Lin, Yi Wang, Gang Chen. DPP4 modulates ACSL4 to promote lipid peroxidation and regulate ferroptosis in pancreatic cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6330.
Abstract 6332: Pim kinase inhibition promotes mitochondrial fission to combat chemoresistance in non-small cell lung cancer
Authors: Chauhan Shailender S. , Toth Rachel K. , Jensen Corbin C. , Kashatus David F. , Casillas Andrea L. , Warfel Noel A. 
Published: September 2020

Abstract
Background: Resistance to chemotherapy represents a major obstacle to the successful treatment of non-small cell lung cancer (NSCLC). A fused mitochondrial network is associated with therapeutic resistance, but the factors controlling mitochondrial dynamics in lung cancer are not fully understood. The goal of this study was to determine how PIM kinases impact mitochondrial dynamics, ROS production, and response to chemotherapy in lung cancer.
Methods: Live cell imaging and microscopy were used to determine the effect of PIM on mitochondrial phenotype and ROS. Biochemical studies were performed to characterize the signaling axis linking PIM1 to Drp1 and mitochondrial fission in lung cancer. Xenograft models of lung cancer were used to evaluate the combination of PIM inhibition and chemotherapy. Immunohistochemistry and transmission electron microscopy were used to analyze mitochondrial phenotype, proliferation, and apoptosis in vivo.
Results: Inhibition of PIM kinases caused excessive mitochondrial fission and significant upregulation of mitochondrial superoxide, increasing intercellular ROS. PIM inhibition significantly increased the protein levels and mitochondrial localization of Drp1. An inverse correlation between PIM1 and Drp1 was confirmed in NSCLC patient samples. Inhibition of PIM sensitized NSCLC cells to chemotherapy and produced a synergistic anti-tumor response, characterized by significantly increased ROS and apoptosis.
Conclusion: PIM kinase expression is an important mechanism of intrinsic and acquired resistance to chemotherapy in NSCLC. PIM inhibition activates Drp1 to promote mitochondrial fission and superoxide production, sensitizing cancer cells to chemotherapy. These data improve our knowledge of how mitochondria are regulated in cancer and provide justification for combining PIM inhibition with chemotherapy in NSCLC.
Citation Format: Shailender S. Chauhan, Rachel K. Toth, Corbin C. Jensen, David F. Kashatus, Andrea L. Casillas, Noel A. Warfel. Pim kinase inhibition promotes mitochondrial fission to combat chemoresistance in non-small cell lung cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6332.
Abstract 6367: KPG-818, a novel cereblon modulator, inhibits hematological malignancies in preclinical models
Authors: Ge Chuansheng , Liao Baisong , Zhang Lei 
Published: September 2020

Abstract
The clinical use of lenalidomide in multiple myeloma (MM), mantle cell lymphoma (MCL) and myelodysplastic syndromes (MDS) represents a significant advance in the treatment of hematological malignancies and has altered the landscape of the blood cancer therapy. Yet, many hematological indications and refractory diseases are still without effective systemic and curative therapies. Here we present KPG-818, a small molecule compound with high affinity binding to cereblon of the E3 ubiquitin ligase (CRBN-CRL4) complex, significantly inhibits the production of the pre-inflammatory cytokines such as TNF-α and IL-6 in LPS-stimulated human PBMC cells, inhibits HUVEC tube formation, and exhibits potent anti-proliferation in multiple lymphoma and multiple myeloma cell lines in vitro. Consistent with the finding in that lenalidomide causes selective degradation of Aiolos and Ikaros, KPG-818 potently inhibits the level of the two lymphoid transcription factors in MM1.S cell line model and human PBMC cells. In in vivo pharmacology studies, KPG-818 significantly inhibits tumor growth in MM.1S multiple myeloma, WSU-DLCL-2 diffuse large B cell lymphoma, DOHH-2 follicular lymphoma, REC-1 mantle cell lymphoma xenograft models. Importantly, KPG-818 prolongs the survival of the mouse cohorts bearing systemic human H929 multiple myeloma in a dose-dependent manner. Moreover, KPG-818 shows favorable DMPK and toxicity profiles in pre-clinical IND enabling studies.
In summary, these immune modulation, anti-angiogenesis and antitumor results encourage the further clinical evaluation of KPG-818 in patients with Multiple Myeloma, Diffuse Large B Cell Lymphoma, Follicular Lymphoma, Mantle Cell Lymphoma and other hematological malignancies.
Citation Format: Chuansheng Ge, Baisong Liao, Lei Zhang. KPG-818, a novel cereblon modulator, inhibits hematological malignancies in preclinical models [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6367.
Abstract 6378: CDC20 is a novel therapeutic target in triple-negative breast cancer
Authors: Sharma Jayesh K. , Alluri Prasanna , Udden Nashir 
Published: September 2020

Abstract
Background:
Approximately 15% of breast cancers lack expression of Estrogen Receptor (ER), Progesterone Receptor (PR) and Human Epidermal Growth Factor Receptor 2 (HER-2), and are referred to as Triple-Negative Breast Cancer (TNBC). Due to a lack of targeted therapies, clinical outcomes in patients with TNBC continue to be poor. Likewise, due to the inherently aggressive biology of the disease, patients are forced to deal with the toughest breast cancer while having the least treatment options. In this study, we identified Cell Division Cycle protein 20 (CDC20), a key regulatory protein that mediates sister chromatid separation in mitosis, as a novel therapeutic target in TNBC.
Methods:
To uncover new drivers of TNBC, we nominated genes that are significantly overexpressed in patients with TNBC, compared to non-TNBCs. After identifying CDC20 as a top hit in this analysis, we used RNAseq analyses, expression microarrays, and Western blotting to assess CDC20 expression levels in breast cancer patients and cell lines. Kaplan-Meier analyses were formed to study the correlation between clinical outcomes and CDC20 expression levels, including recurrence-free survival, metastasis-free survival and overall survival. shRNA and siRNA-mediated knockdown of CDC20 in TNBC cell lines were employed to study the role of CDC20 in TNBC proliferation, invasion, and migration.
Results:
CDC20 was significantly overexpressed in TNBCs (compared to non-TNBCs) patients and is a predictor of poor clinical outcomes and radiation resistance. CDC20 expression was also significantly higher in TNBC cell lines compared to non-TNBC cell lines, reflecting what is seen in clinical data sets, such as in The Cancer Genome Atlas. Sh and siRNA-mediated knockdown of CDC20 expression resulted in decreased proliferation, invasion and migration in TNBC cell lines.
Conclusions and future directions:
Our findings support the development of pharmacologic strategies to inhibit CDC20 function as a potential targeted therapy against TNBC. Efforts are underway to validate our findings in vivo in xenograft models of TNBC in mice.
Citation Format: Jayesh K. Sharma, Prasanna Alluri, Nashir Udden. CDC20 is a novel therapeutic target in triple-negative breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6378.
Abstract 6384: TEAD inhibition reduces tumor proliferation in Merlin null meningioma and schwannoma
Authors: Laraba Liyam , de Guibert Julio Grimm , Tang Tracy T. , Post Leonard , Parkinson David B. 
Published: September 2020

Abstract
Introduction:
Meningiomas are the most common intracranial tumor and arise from the arachnoidal cell layer of the meninges. Schwannomas develop from Schwann cells which provide myelin and trophic support in the peripheral nerves. The tumor suppressor Merlin is deleted in approximately 50-60% of meningiomas and 70% of schwannomas. Loss of Merlin results in dysregulation of the Hippo pathway and consequent aberrant activation of the transcriptional coactivators YAP and TAZ. Nuclear localisation of YAP and TAZ has been shown to drive tumor phenotypes in many cancers. The TEAD family of transcription factors are major targets of YAP and TAZ-dependent signaling. TEAD family members undergo autopalmitoylation and this modification is required for transcriptional activation by YAP or TAZ. Vivace therapeutics have identified small molecule inhibitors of autopalmitoylation that block the interaction of TEAD family members with YAP and TAZ. This study seeks to establish the efficacy of small molecule inhibitors of TEAD activity in meningioma and schwannoma tumor cells.
Experimental Procedures:
Meningioma cell lines, primary human meningioma and schwannoma cells, as well as a schwannoma mouse model (PerisotinCRE /NF2 fl/fl) were treated with Vivace inhibitors to assess their effects upon tumor cell proliferation and TEAD driven transcription.
Results:
TEAD inhibition significantly reduced the proliferation of the BenMen-1 meningioma cell line, as well as in primary human meningioma cells. In schwannoma, inhibitors reduced proliferation and also reduced the expression of CTGF, a target of TEAD activation in both primary human meningioma and schwannoma cells. These novel inhibitors are also currently being tested in the Periostin CRE-NF2fl/fl schwannoma mouse model to evaluate their efficacy in vivo.
Conclusions:
The use of these novel compounds to inhibit TEAD function shows great potential as an effective treatment for reducing the rate of cell proliferation in meningioma and schwannoma, two clinically important tumor types.
Citation Format: Liyam Laraba, Julio Grimm de Guibert, Tracy T. Tang, Leonard Post, David B. Parkinson. TEAD inhibition reduces tumor proliferation in Merlin null meningioma and schwannoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6384.