tbuckley/cabot-search huggingface dataset:
Abstract 516: The role of clathrin-mediated endocytosis of EGFR in glioblastoma cell viability and cell cycle progression
Authors: Aaron Deter, Andrew J. Tsung, Maheedhara R. Guda, Swapna Asuthkar, Kiran Velpula
Journal: Cancer Research (2024)

Abstract Glioblastoma (GBM) is characterized by poor prognosis and overexpression of epidermal growth factor receptor (EGFR). EGFR signaling is regulated through endocytosis, including clathrin-mediated endocytosis. We hypothesized that clathrin-mediated EGFR endocytosis promotes GBM cell viability and proliferation. Analysis of patient data from the Gliovis database revealed decreased overall survival in GBM patients with above-median clathrin expression (n=262) compared to below-median expression (n=263, p&amp;lt;0.05). Immunocytochemistry and Western blot analysis confirmed increased clathrin levels in GBM patient samples compared to normal brain tissue (n=15, p&amp;lt;0.01). To determine the functional effect of inhibiting clathrin-mediated endocytosis, U87 and U251 GBM cells were treated with 15 μM Pitstop-2, a clathrin inhibitor, for 24 hours. Pitstop-2 significantly reduced clathrin levels and cell viability by 40% compared to control (p&amp;lt;0.001, n=3). Cell cycle analysis by flow cytometry revealed Pitstop-2 treatment led to G2/M arrest in both cell lines versus control (p&amp;lt;0.01, n=3). Together, these findings indicate clathrin-mediated endocytosis of EGFR may promote GBM cell viability and proliferation. Further studies on the effects of clathrin inhibition on EGFR signaling and tumor growth in vivo will elucidate the therapeutic potential of targeting this pathway. Citation Format: Aaron Deter, Andrew J. Tsung, Maheedhara R. Guda, Swapna Asuthkar, Kiran Velpula. The role of clathrin-mediated endocytosis of EGFR in glioblastoma cell viability and cell cycle progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 516.
Abstract 6321: Developing a lenalidomide-inducible safety switch for CAR T cell therapy
Authors: Ditsa Sarkar, William Lin, Joanna Y. Kim, Nelson H. Knudsen, Isabel C. Lane, Tamina Kienka, Michael C. Kann, Amanda A. Bouffard, Andy Cheng, Marcela V. Maus, Robert T. Manguso, Max Jan
Journal: Cancer Research (2024)

Abstract While CAR T cell therapy is a medical breakthrough against various hematological malignancies, yet treatment failures often occur at least in part due to excessive engineered T cell activity leading to severe toxicities. To combat this, strategies pairing CAR T cells with safety systems, for example, suicide switches engineered to induce cell death are being actively pursued. However, existing designs have limited performance characteristics and generally use unapproved small molecule controllers or non-human sequences. To overcome these issues, we have developed a novel suicide switch leveraging the well-tolerated, FDA-approved anti-cancer drug lenalidomide, as a controller of the stability of fusion proteins tagged with a “degron” sequence. Specifically, we engineered a stoichiometric pair of transgenes using the apoptotic DNase pair, caspase activating DNase (CAD) and its degron tagged inhibitor (ICAD-degron). We hypothesized that the overexpressed ICAD-degron could restrain CAD, until lenalidomide treatment degrades ICAD to unleash CAD for apoptosis. We found that our system was stably overexpressed and rapidly induced cell death even at sub-nanomolar concentrations of lenalidomide. A comparison of our design with the frontline safety switch, inducible Caspase 9 in primary human T cells revealed that the lenalidomide-induced suicide switch enabled more complete depletion of engineered cells. We tested the effects of our suicide switch on CAR T cell function and found comparable proliferation and tumor cell cytolysis with fast depletion upon lenalidomide addition. In vivo, lenalidomide suicide switch CAR T cells exhibited similar anti-tumor function as control CAR T cells and were rapidly depleted after drug treatment. In summary, utilizing all human sequences and a clinically approved drug controller, we developed a suicide switch that is well tolerated and can rapidly induce cell death even at sub-therapeutic concentrations of lenalidomide. More broadly, chemogenetic regulation of stoichiometric protein pairs is a generalizable strategy for post-translational control of highly active transgenic elements. Citation Format: Ditsa Sarkar, William Lin, Joanna Y. Kim, Nelson H. Knudsen, Isabel C. Lane, Tamina Kienka, Michael C. Kann, Amanda A. Bouffard, Andy Cheng, Marcela V. Maus, Robert T. Manguso, Max Jan. Developing a lenalidomide-inducible safety switch for CAR T cell therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6321.
Abstract 6320: CAR-T cells targeting LGR5: An effective treatment for chemotherapy resistant ovarian cancer
Authors: Wanqi (Jady) Wang, Veronika Bandara, Noor A. Lokman, Zoe K K. Price, Tannith M. Noye, Silvana Napoli, Batjargal Gundsambuu, Martin K. Oehler, Simon C. Barry, Carmela Ricciardelli
Journal: Cancer Research (2024)

Abstract Ovarian cancer is the second leading cause of cancer-related mortality among gynaecological cancers in the Western world. CAR-T cell therapy is an adoptive immunotherapy used to treat some blood cancers. This study has investigated whether leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) is a suitable target for CAR-T cell therapy for ovarian cancer. We assessed the cytotoxic effects of LGR5-targeting CAR-T cells on a range of ovarian cancer cell lines and primary serous ovarian cancer cells derived from patient ascites (at diagnosis and following relapse with chemotherapy resistant disease) in monolayer culture, 3D spheroid assays and patient-derived explant assays. OVCAR3 and a chemoresistant patient-derived xenograft (PDX) models have been used to assess whether LGR5-targeting CAR-T cells can inhibit growth and metastasis in vivo. We found that LGR5 is highly expressed in high-grade serous ovarian carcinoma (HGSOC) cancer cell lines and LGR5 expression was increased in chemotherapy resistant primary ovarian cancer cells. We demonstrated that LGR5-targeting CAR-T cells were cytotoxic and significantly inhibited the survival of ovarian cancer cell lines and chemotherapy-resistant primary ovarian cancer cells with high LGR5 expression levels in both monolayer culture and 3D spheroids compared to un-transduced CD3+ T cells. In patient-derived explant assays, we observed increased apoptosis in HGSOC tissues expressing high LGR5 following treatment with LGR5-targeting CAR-T cells. In vivo, LGR5-targeting CAR-T cell treatment decreased the tumour burden in mice with OVCAR3 xenografts and a chemotherapy-resistant PDX model with high LGR5 expression, compared to CD3+ T cells. In summary, LGR5-targeting CAR-T cells have great potential to be developed as a novel immunotherapy for ovarian cancer. Citation Format: Wanqi (Jady) Wang, Veronika Bandara, Noor A. Lokman, Zoe K K. Price, Tannith M. Noye, Silvana Napoli, Batjargal Gundsambuu, Martin K. Oehler, Simon C. Barry, Carmela Ricciardelli. CAR-T cells targeting LGR5: An effective treatment for chemotherapy resistant ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6320.
Abstract 5187: VistaPlex immunofluorescence assay panels provide reliable deep spatial phenotyping for diverse immuno-oncology applications
Authors: Arne Christians, Charles E. Jackson, Jannik Boog, Matthew H. Ingalls, Adam Northcutt, Kayla E. Cashion, Jonah Rauer, Karen Kwarta, J Spencer Schwarz, Oliver Braubach
Journal: Cancer Research (2024)

Abstract Multiplex immunofluorescence (mIF) is a powerful tool that enables deep phenotyping of immune and cancer cells across a wide variety of tissue types. The initial effort and cost required to develop high-plex mIF panels is significant and poses a considerable hurdle for adoption of spatial biology. To streamline high-plex assay development, we developed a process for creating and validating multiplex antibody panels for use in immuno-oncology applications that leverage CellScape™, an automated end-to-end platform for Precise Spatial Multiplexing. Our multiplex assay development was a rigorous, multi-stage, iterative process to evaluate antibodies for suitability, specificity, and reproducibility. These assay panels are formulated as ready-to-use VistaPlex™ assay kits and are intended to enable rapid, reliable spatial phenotyping of key immune populations. To confirm the utility of VistaPlex, we deployed the Human FFPE Spatial Immune Profiling Panel to stain and image various FFPE tissue samples on the CellScape platform. With CellScape, tissues are mounted in enclosed fluidic chambers while on-instrument staining, imaging and signal erasure are conducted in iterative rounds. The panel presented here contains antibodies against 16 common biomarkers used in immune-oncology applications. Among these are CD3, CD4, CD8, CD20, and CD45 to detect cell lineages, PD-1 and PD-L1, to interrogate immune checkpoints, and markers that inform about cell state and activation. Spatial immune profiling data were obtained from human tonsil, colon, breast, and lung tissue samples. Deep immune phenotyping was performed using unsupervised clustering analysis and AI-assisted cluster labelling, and biomarker distributions were studied in the context of cellular neighborhoods and other proximity analyses. Overall, we identified more than 19 cell phenotypes with varying frequencies and spatial arrangements across tissue samples. Our data are robust and demonstrate that VistaPlex Assay kits for spatial profiling present an efficient and cost-effective solution for users that want to break into spatial biology. Citation Format: Arne Christians, Charles E. Jackson, Jannik Boog, Matthew H. Ingalls, Adam Northcutt, Kayla E. Cashion, Jonah Rauer, Karen Kwarta, J Spencer Schwarz, Oliver Braubach. VistaPlex immunofluorescence assay panels provide reliable deep spatial phenotyping for diverse immuno-oncology applications [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5187.
Abstract 6290: Effects of a circuit, interval-based exercise program on vascular function among cancer survivors
Authors: Cami N. Christopher, Dong-Woo Kang, Paola Gonzalo-Encabo, Rebekah L. Wilson, Amber J. Normann, Mary K. Norris, Christina M. Dieli-Conwright
Journal: Cancer Research (2024)

Abstract Background: Cancer survivors are at an increased risk of cardiovascular comorbidity, including atherosclerosis, hypertension, and heart failure, due to negative impacts of cancer treatments on vascular function. Exercise is recommended in recent cardio-oncology rehabilitation guidelines and has been shown to improve vascular function in clinical populations; however, its effects on vascular function are understudied in clinical oncology settings. Purpose: This pilot study examined whether a circuit, interval-based exercise intervention can improve vascular function, assessed by brachial artery flow-mediated dilation (baFMD) and carotid intima media thickness (cIMT) in breast, prostate, and colorectal cancer survivors. Methods: Overweight or obese (BMI&amp;gt;25.0 kg/m2), sedentary breast, prostate or colorectal cancer survivors were randomized to exercise (n=60) or usual care (n=30). Survivors in the 4-month exercise intervention trained three times/week, in a circuit, interval-based supervised moderate-vigorous aerobic (65-85% of VO2max) and resistance (65-85% of 1-repetition maximum) program. cIMT and baFMD were measured at baseline and post-intervention via an ultrasound. Paired t-tests and repeated-measures analysis of variance were run to assess within- and between-group differences. Results: The study sample included breast (n=38), prostate (n=24), colorectal (n=28) cancer survivors who were 63.2 ± 10.8 years old, completed chemotherapy and/or radiation (75%) and were obese (87%). Post-intervention, baFMD significantly increased in the exercise group compared to the control group (between-group mean difference: 6.3%; 95% CI: [1.9 to 9.3], p=0.001). There was also a significant reduction in cIMT in the exercise group compared to the control group (between-group mean difference: -0.039mm, 95% CI: [-0.080 to -0.009], p=0.002). Conclusions: Our findings in this pilot study support that a circuit, interval-based aerobic and resistance exercise intervention may improve vascular function in breast, prostate, and colorectal cancer survivors. Future studies are recommended to understand how exercise interventions can be utilized clinically to improve cardiovascular disease risk and co-morbidity among cancer survivors. Citation Format: Cami N. Christopher, Dong-Woo Kang, Paola Gonzalo-Encabo, Rebekah L. Wilson, Amber J. Normann, Mary K. Norris, Christina M. Dieli-Conwright. Effects of a circuit, interval-based exercise program on vascular function among cancer survivors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6290.
Abstract 5197: Identification of novel molecular biomarkers for predicting postoperative recurrence of ampulla of Vater carcinoma
Authors: Hyemin Kim, Jin Ho Choi, Hyoung-oh Jeong, Aryoung Kim, Se-Hoon Lee, Kwang Hyuck Lee, Kyu Taek Lee, Jong Kyun Lee, Semin Lee, Joo Kyung Park
Journal: Cancer Research (2024)

Abstract Background: Ampulla of Vater (AoV) carcinoma is a rare tumor that accounts for 20 % of periampullary cancers. Surgical resection is the only treatment that can expect cure of disease, and there is still an unmet need to predict postoperative recurrence. In this study, we investigated the novel molecular biomarkers that can predict the risk of recurrence after surgery with AoV carcinoma. Methods: In this retrospective study, we collected the surgically resected tissue and medical records of patients who were diagnosed with AoV carcinoma at Samsung Medical Center from January 2005 to December 2020. Patients were classified patients according to the initial stage and experience of tumor recurrence. Whole transcriptomic analysis using primary AOV tumor and recurred tumor tissue samples was conducted to identify the molecular biomarker for tumor recurrence. Results: A total of 40 tumor tissue from primary site in non-recurrence group, 22 tumor tissue from primary site in recurrence group, and paired 22 tumor tissue from recurrence site were analyzed. A total of 1005 genes differentially expressed between primary tumor of non-recurrence group and recurrence group were found. Gene set enrichment analysis showed that pathways related to fatty acid metabolism, adipogenesis, oxidative phosphorylation, and hypoxia were upregulated, and pathways associated with interferon gamma response, and mTOR signaling were downregulated in recurrence group. These pathways were significantly affecting the recurrence free survival which was verified with TCGA data, and we further identified some candidate genes including PIM3, IGFBP4, SLC19A1, HIF1A and CXCL11 to predict tumor recurrence . Moreover, we found candidates for single gene level biomarkers to predict early tumor recurrence in N0 stage. Low expression of UQCC3 and high expression of CLCNKB was related to early tumor recurrence. Conclusions: We found the candidates for novel molecular level biomarker to predict postoperative recurrence of AoV carcinoma. In the future, it is necessary to develop a predictive model for the risk of recurrence after surgical resection for AoV carcinoma. Citation Format: Hyemin Kim, Jin Ho Choi, Hyoung-oh Jeong, Aryoung Kim, Se-Hoon Lee, Kwang Hyuck Lee, Kyu Taek Lee, Jong Kyun Lee, Semin Lee, Joo Kyung Park. Identification of novel molecular biomarkers for predicting postoperative recurrence of ampulla of Vater carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5197.
Abstract 631: Functional genetics of APR-246 rescuable TP53 mutants
Authors: Anais Saunders, Caili Tong, Anthony N. Karnezis, Gary S. Leiserowitz, Jeremy R. Chein
Journal: Cancer Research (2024)

Abstract TP53, often referred to as the guardian of the genome, encodes for the p53 tumor suppressor protein, and is one of the most frequently mutated genes in human cancers. Some cancer sub-types, such as non-small cell lung carcinoma (NSCLC) and high grade serous carcinoma (HGSC), have high TP53 mutation rates reaching up to 56% and 96%, respectively. Given its multi-faceted role in human cancers, there have been several emerging therapeutic approaches targeting mutant p53. APR-246 is a small molecule drug currently in clinical trials for the functional rescue of p53 missense mutants, the most common type of p53 mutant protein, across various cancer types. APR-246 is proposed to bind mutant p53 and promote thermodynamic stabilization of the protein allowing it to regain wild-type-like conformation and consequentially regain WT-like functionality. However, there has yet to be a functional genomic screening of p53 mutants to systematically catalog which mutants are rescuable by APR-246. To address this critical gap, we have performed functional genetic screenings using a TP53 mutagenesis library. This pooled lentiviral library contains ~8,000 amino acid variants, spanning the entirety of the TP53 gene. Following stable transduction of this library into p53-null NSCLC and HGSOC cell lines, we performed functional screenings against sublethal doses of APR-246. Next-generation sequencing of the untreated and treated cell population allows for comparison of variant representation and determination of APR-246-sensitivity of p53 mutants. Preliminary statistical analysis of our screens has identified a pool of 117 “hit” mutants which are significantly depleted following treatment, indicative of APR-246-sensitivity. Two of these mutants, C242F and G266V, are non-functional, damaging mutations which occur in patients. Identifying p53 mutants that can be rescued by APR-246 will help identify which patients may benefit most from treatment with the drug. Citation Format: Anais Saunders, Caili Tong, Anthony N. Karnezis, Gary S. Leiserowitz, Jeremy R. Chein. Functional genetics of APR-246 rescuable TP53 mutants [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 631.
Abstract 5199: Protease-activated CDCP1 as a marker for aggressive primary prostate cancer and castration resistance
Authors: Ruusu-Maaria Merivirta, Timo-Pekka Lehto, Antti Rannikko, Tuomas Mirtti, Hannu Koistinen
Journal: Cancer Research (2024)

Abstract CUB domain-containing protein 1 (CDCP1) is a type 1 transmembrane protein overexpressed in many cancers, including prostate cancer. CDCP1 has been associated with tumor progression, metastasis, drug resistance and poor prognosis in prostate cancer, making it a potential prognostic biomarker and therapeutic target. It has been shown to be overexpressed in a subset of castration resistant prostate cancers (CRPC) and cooperate with the loss of tumor suppressor PTEN to promote metastatic dissemination. Extracellular serine proteases activate CDCP1 by cleaving it into an N-terminal and C-terminal fragments. Proteolytic cleavage has been associated with the tumor-promoting functions of CDCP1. We studied the expression of full-length and cleaved form of CDCP1 in grade group 2-4 primary prostate cancer tissues and CRPCs using immunohistochemistry. Total CDCP1 staining was observed in 60% of primary prostate cancer samples, while the staining of cleaved CDCP1 was somewhat less frequently observed (45%). The results will be further analyzed regarding the PTEN status and for association with survival of the patients. In conclusion, so far, our results have indicated that cleaved CDCP1, which likely represents activated CDCP1, is detectable in GG 2-4 prostate cancers. Citation Format: Ruusu-Maaria Merivirta, Timo-Pekka Lehto, Antti Rannikko, Tuomas Mirtti, Hannu Koistinen. Protease-activated CDCP1 as a marker for aggressive primary prostate cancer and castration resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5199.
Abstract 517: 2OHOA-mediated furin inhibition: Disrupting Notch via processing, transcription, and ADAM downregulation
Authors: Raquel Rodríguez-Lorca, Roberto Beteta-Göbel, Ramón Roman, Victoria Lladó, Pablo V. Escribá, Paula Fernández-García
Journal: Cancer Research (2024)

Abstract Purpose Glioblastomas (GBMs) are highly treatment-resistant and aggressive brain tumors. Herewe assessed the potential of melitherapy to treat GBM, a strategy based on regulating themembrane’s structure and organization to modify aspects of intracellular signaling. In thiscontext, we have evaluated the effects of 2-hydroxyoleic acid (2OHOA) on GBM cells, acompound currently under study in a phase IIB/III clinical trial for newly diagnosed GBMpatients. The current study aims to determine whether 2OHOA modulates the Notch pathway aspart of its antitumoral mechanism, as seen its relevance driving the pathogenesis of GBM. Methods The effect of 2OHOA was evaluated on different components of the pathway usingseveral methods: W-blot, Q-PCR, and confocal microscopy. The relevance of HES1 in itsmechanism of action was evaluated by its overexpression and pathway activation assays byJagged1. To analyze Notch receptor processing, we performed subcellular fractionation andcolocalization studies. Furin activity was assessed by fluorescence assays measuring its substratecleavage and its binding affinity to 2OHOA was determined by surface plasmon resonance. Results 2OHOA suppresses both the Notch3 and Notch2 signaling pathways in GBM cell linesusing a two-fold mechanism. Notch3 signaling is abolished by repressing its transcription.Instead, Notch2 pathway is hindered by blocking its first cleavage through the inactivation offurin activity by physical association. Consequently, the Notch2 receptor is retained in the Golgicomplex, preventing its trafficking to the plasma membrane to initiate the signaling cascade.Moreover, overexpression of its target gene, HES1, partially dampened the drug's antiproliferative effect showing the relevance of this pathway in the 2OHOA pharmacologicalefficacy. In addition, considering the levels of Notch intracellular domain (NICD) obtained inJagged1 assays in conjunction with 2OHOA, we evaluated the second cleavage of the Notchprocessing, being also downregulated, as ADAM10 constitutes a furin substrate. Conclusions These findings elucidate that the antitumoral activity of 2OHOA involves theinhibition of Notch signaling, potentially driven by the direct inhibition of furin. This reveals anovel molecular target for this bioactive lipid in the therapeutic approach to treating GBM. Citation Format: Raquel Rodríguez-Lorca, Roberto Beteta-Göbel, Ramón Roman, Victoria Lladó, Pablo V. Escribá, Paula Fernández-García. 2OHOA-mediated furin inhibition: Disrupting Notch via processing, transcription, and ADAM downregulation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 517.