bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract A89: Identification of novel costimulatory pathways in T cells with functional assays on the Membrane Proteome Array (MPA)
Authors: Sullivan Jonathan T. , Huston-Paterson Duncan , Azuelos Charles , Doranz Benjamin J. 
Published: June 2021

Abstract
To identify membrane proteins involved in cytotoxic T-cell (CTL) stimulation, we screened our proprietary Membrane Proteome Array (MPA) for activation of CTLs. The MPA comprises 5,300 different human membrane proteins, each overexpressed in live HEK-293 cells. CTLs were layered on the MPA, incubated overnight, stained for an activation marker, and quantified for expression by high-throughput flow cytometry. We identified 38 putative membrane proteins involved in CTL activation. Eight of these “hits” are known activators of CTLs, such as CD86. Other hits include membrane proteins that are involved in multiple functional activities. Here, we describe the functional validation of two of these previously unreported stimulatory proteins. For Hit A, we converted the extracellular domain to an Fc-fusion protein and used the construct to probe the MPA for binding partners. We identified two proteins that interact with Hit A: one protein found on neurons and one protein found on T cells. Hit B was a commercially available molecular agonist. Using the agonist in our assay, we were able to modulate the extent to which this target stimulated CTLs. In addition to identifying factors of CTL activation, we are currently using the MPA to identify novel viral receptors and therapeutic targets for neurodegenerative diseases, as well as deorphaning and testing the specificity of antibodies.
Citation Format: Jonathan T. Sullivan, Duncan Huston-Paterson, Charles Azuelos, Benjamin J. Doranz. Identification of novel costimulatory pathways in T cells with functional assays on the Membrane Proteome Array (MPA) [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr A89.
Abstract A92: Assessing the T-cell exhaustion status of TCR discovery outputs
Authors: Mallini Paraskevi , Bravo-Lopes Filipa , Lech Karolina , Malla Sunir , Busz Maria , Davies Nathaniel , Hurst Jacob , Williams Luke , Davis Sterenn , Teng Michelle 
Published: June 2021

Abstract
Identification of antigen-specific T cell receptors (TCRs) is an essential component of the ImmTAC (Immune mobilizing monoclonal TCRs Against Cancer) platform at Immunocore. ImmTAC molecules are formed of a soluble TCR fused to an anti-CD3 effector function that engages, redirects and activates T cells to kill cancerous cells. TCRs recognize peptide antigens presented on the surface of the cancer cell by human leukocyte antigen (HLA). Thus, a fundamental step in our pipeline is to isolate T-cell receptors specific for validated cancer antigens for downstream development. T cells are isolated from whole blood of healthy donors to identify antigen-specific T cell clones using an in vitro model that consists of several stimulation steps. Activated CD8+ T cells are sorted into single cells for subsequent analysis and characterization. Despite the relative success of this approach, often analysis of T-cell clones is limited by low or absent mRNA expression for either or both TCR alpha (TRAV) and beta (TRBV) chains. We predict that TCR downregulation may result from overstimulation of T cells, leading to exhaustion. Here, we aimed to establish an in vitro model of T-cell exhaustion that would enable us to better understand the molecular mechanisms behind this process and thus facilitate method development. We induced extreme conditions of stimulation using CD3/CD28 beads and recombinant human IL-2 (rhIL-2) for 2-3 weeks. Whole-transcriptome analysis of the resulting activated T cells was compared to rested cells using a 5′ single-cell RNA-seq method from 10X Genomics (California, USA). Our preliminary analysis indicates that the activated T cells express several checkpoint inhibitors at higher levels. Our findings will be further investigated by performing full-length RNA sequencing of previously isolated single T-cell clones with low TRAV and/or TRBV detection rates. By identifying a molecular signature that represents the phenotype of exhausted T cells, we can potentially assess the state of T cells in TCR discovery outputs. Most importantly, determination of the expression levels of inhibitory receptors that are responsible for the decrease or loss of TCR expression is expected to enhance our understanding of the potential impact of T-cell exhaustion.
Citation Format: Paraskevi Mallini, Filipa Bravo-Lopes, Karolina Lech, Sunir Malla, Maria Busz, Nathaniel Davies, Jacob Hurst, Luke Williams, Sterenn Davis, Michelle Teng. Assessing the T-cell exhaustion status of TCR discovery outputs [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr A92.
Abstract A98: Molecular dynamics study of pH-dependent interactions between immune checkpoint receptor PD-1 and PD-L1
Authors: Alexandrov Vitaly , Klyukin Konstantin 
Published: June 2021

Abstract
Understanding of how small variations in checkpoint protein chemistry (e.g., mutations) and tumor immune microenvironment (e.g., pH) influence receptor-ligand binding and define both the mechanisms and magnitude of immune response is of great importance, but the molecular details are still missing. Here, we employ enhanced free-energy sampling molecular dynamics simulations to unveil pH-dependent binding/unbinding mechanisms and kinetics of PD-1/PD-L1 interactions. By identifying the binding pocket in the PD-1/PD-L1 complex, we show a key role of the His68 protonation state in PD-1 in the complex stabilization at low pH. Specifically, we estimate the unbinding free-energy barrier to be around 15 kJ/mol higher at pH 5.5 than at pH 7.4. The estimated ratio of binding (kon) and unbinding (koff) rate constants is found to agree well with recent experimental data on KD values at different pH. Also, simulations show an important role of solvation state of the binding pocket in mediating polar interactions at the PD-1/PD-L1 binding interface. These initial molecular insights are important for further engineering of binding/unbinding kinetics to formulate more efficient immune checkpoint blockade strategies.
Citation Format: Vitaly Alexandrov, Konstantin Klyukin. Molecular dynamics study of pH-dependent interactions between immune checkpoint receptor PD-1 and PD-L1 [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr A98.
Abstract B06: Immune inhibitory receptors restrain hyperactivated effector T cells in the tumor microenvironment
Authors: Lu Binfeng , Yang Min , Du Wenwen , Zhai Wensi , Sun Runzi , Yue Cuihua , Jiang Jingting 
Published: June 2021

Abstract
The immune checkpoint blockade (ICB) immunotherapy of cancer has prolonged overall survival for some patients; however, the response rates are still low. Rational design of combination therapy targeting multiple immune checkpoint inhibitors promises to significantly improve the current ICB therapy. TIM-3 and LAG3 are highly expressed in the tumoral-infiltrating lymphocytes (TIL) and monoclonal antibodies targeting these immune inhibitors have been subjected to intensive clinical development. However, the underlying mechanisms are not fully understood. In order to dissect the mechanisms, we first systematically examined Tim-3 expression in immune cells in mouse tumors. We found Tim-3 was expressed in large portions of Treg, CD4, CD8 T cells, DC1, M1, and MDSC. Administration of a none-depleting Tim-3 antibody alone did not affect tumor progress, but combination treatment with Tim-3 and PD-1 mAbs resulted in a synergistic antitumor efficacy. Mechanistically, treatment with either Tim-3 mAbs or PD-1/Tim-3 mAbs led to a decrease of Treg in the tumor microenvironment (TME). In addition, Tim-3 mAbs and PD-1 mAbs either alone or synergistically increased IFN-γ and granzymes production by CD4+ and CD8+ TIL. Interestingly, combined treatment with Tim-3 and PD-1 mAbs greatly increased the expression of Lag3 in TIL, suggesting induction of hyperactivated effector T cells is associated with increased level of checkpoint inhibitory molecules. We further found that the antitumor efficacy with triple combination of PD-1, Tim-3, and Lag3 mAbs was much greater than double combination. Our data demonstrated that checkpoint inhibitors are genetically encoded to control the graded activation of effector T cells and simultaneous blockade of several inhibitors is necessary to fully unleash the power of immunotherapy of cancer.
Citation Format: Binfeng Lu, Min Yang, Wenwen Du, Wensi Zhai, Runzi Sun, Cuihua Yue, Jingting Jiang. Immune inhibitory receptors restrain hyperactivated effector T cells in the tumor microenvironment [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr B06.
Abstract B32: Cxcr3-expressing leukocytes are necessary for neurofibroma formation in mice
Authors: Fletcher Jonathan S. , Wu Jianqiang , Jessen Walter J. , Pundavela Jay , Dombi Eva , Kim Mi-Ok , Rizvi Tilat A. , Chetal Kashish , Salomonis Nathan , Ratner Nancy 
Published: June 2021

Abstract
Plexiform neurofibroma is a major contributor to morbidity in neurofibromatosis type I (NF1) patients. Macrophages and mast cells infiltrate neurofibroma, and data from mouse models implicate these leukocytes in neurofibroma development. Anti-inflammatory therapy targeting these cell populations has been suggested as a means to prevent neurofibroma development. Here, we compare gene expression in inflamed nerves from NF1 models that invariably form neurofibroma to those with inflammation driven by EGFR overexpression, which rarely progresses to neurofibroma. We find that the chemokine Cxcl10 is uniquely upregulated in NF1 mice that invariably develop neurofibroma. Global deletion of the Cxcl10 receptor Cxcr3 prevented neurofibroma development in these neurofibroma-prone mice. Cxcr3 expression localized to T cells and dendritic cells (DCs) in both inflamed nerves and neurofibromas. These data support a heretofore unappreciated role for T cells/DCs in neurofibroma initiation.
Citation Format: Jonathan S. Fletcher, Jianqiang Wu, Walter J. Jessen, Jay Pundavela, Eva Dombi, Mi-Ok Kim, Tilat A. Rizvi, Kashish Chetal, Nathan Salomonis, Nancy Ratner. Cxcr3-expressing leukocytes are necessary for neurofibroma formation in mice [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr B32.
Abstract B40: Translational control of tumor immune escape via the eIF4F-STAT1-PDL1 axis in melanoma
Authors: Cerezo Michael , Guemiri Ramdane , Girault Isabelle , Robert Caroline , Vagner Stephan 
Published: June 2021

Abstract
Preventing the immune escape of tumor cells by blocking inhibitory checkpoints, such as the interaction between Programmed Death Ligand 1 (PD-L1) and Programmed Death-1 (PD-1) receptor, is a powerful anticancer approach. However, many patients do not respond to checkpoint blockade. Tumor PD-L1 expression is a potential efficacy biomarker, but the complex regulatory mechanisms underlying its regulation are not completely understood. Here, we show that the eIF4F eukaryotic translation initiation complex, which binds the 5’ cap of mRNAs, regulates the surface expression of interferon-induced PD-L1 on cancer cells by regulating translation of the mRNA encoding the STAT1 transcription factor. eIF4F complex formation correlates with response to immunotherapy in human melanoma. Pharmacologic inhibition of eIF4A, the RNA helicase component of eIF4F, elicits powerful antitumor immune-mediated effects via PD-L1 downregulation. Thus, eIF4A inhibitors, in development as anti-ancer drugs, may also act as cancer immunotherapies.
Citation Format: Michael Cerezo, Ramdane Guemiri, Isabelle Girault, Caroline Robert, Stephan Vagner. Translational control of tumor immune escape via the eIF4F-STAT1-PDL1 axis in melanoma [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr B40.
Abstract B41: BRAF targeting sensitizes resistant melanoma to cytotoxic T cells
Authors: Atay Cigdem , Kwak Taekyoung , Lavilla-Alonso Sergio , Richards Allison , Moberg Valerie , Pilon-Thomas Shari , Schell Michael , Messina Jane L. , Rebecca Vito W. , Zhang Gao , Weber Jeffrey S. , Herlyn Meenhard , Sarnaik Amod A. , Gabrilovich Dmitry I. 
Published: June 2021

Abstract
Although treatment of combination therapy with BRAF and MEK inhibitors in patient with melanoma has shown longer duration of response and higher rate of tumor responses, recurrence of tumor from dual targeted therapy in patients with metastatic melanoma has still remained a challenge to overcome. Here, we provide new therapeutic approaches for BRAF inhibitors-resistant melanoma model that upregulation of mannose-6-phosphate receptor (M6PR) on melanoma by treatment of BRAF inhibitors enhances tumor cytotoxicity level via Granzyme B uptake, which is major component of cytotoxic activity of cytotoxic T lymphocytes (CTLs). Our results demonstrate that treatment of BRAF inhibitor increases M6PR expression temporally in both sensitive and resistant BRAFi melanoma cell lines as well as tumor-bearing mouse models (NOD/SCID). Cytotoxic activity of human melanoma cells by co-culture with patient-derived tumor-infiltrating lymphocytes (TILs) shows correlation with M6PR expression level. Furthermore, treatment of mice bearing resistant tumor with BRAFi enhances the antitumor effect of adaptive TILs transfer. In pilot clinical trials of 16 patients with metastatic melanoma, our results support that administration of BRAF inhibitor to patient shows high level of M6PR expression on tumor tissues. Also, combination treatment of BRAF inhibitor and adaptive cell transfer with patient-derived TILs shows promising clinical results in terms of longer response and tumor-free survival. Taken together, BRAF targeted therapy upregulates M6PR level, which enhances activity of TILs to kill resistant melanoma, providing new therapeutic approaches for patients who have recurrence melanoma.
Note: This abstract was not presented at the conference.
Citation Format: Cigdem Atay, Taekyoung Kwak, Sergio Lavilla-Alonso, Allison Richards, Valerie Moberg, Shari Pilon-Thomas, Michael Schell, Jane L. Messina, Vito W. Rebecca, Gao Zhang, Jeffrey S. Weber, Meenhard Herlyn, Amod A. Sarnaik, Dmitry I. Gabrilovich. BRAF targeting sensitizes resistant melanoma to cytotoxic T cells [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr B41.
Abstract B45: NFAT5/TonEBP mediated anti-tumor efficiency of high salt activated CD4+T lymphocytes
Authors: Amara Suneetha , Yenuga Pooja , Zent Roy , Tiriveedhi Venkataswarup 
Published: June 2021

Abstract
Cell-based immunotherapy is rapidly emerging as a promising alternative to conventional chemotherapy-based treatment for cancer. Previous studies have shown that high salt treatment induces naive CD4+T lymphocytes to differentiate into a highly proinflammatory Th17 phenotype. In our current study, we analyzed the ability of salt treatment to induce cancer-specific Th17 lymphocytes. Naive CD4+T cells isolated by immunomagnetic bead isolation from splenocytes of 10-week-old BALB/c mice were treated in vitro with high salt (Δ0.05 M NaCl) along with CD3 monoclonal antibodies (mAbs), CD28 mAbs and IL-2 for 4 days along with heat killed 4T1 breast cancer cells. The isolated CD4+CCR6+CD45RA-CXCR3- cells were tested for IL-17 expression by flow cytometry and determined to be &gt;95% pure. Orthotopic murine breast tumor models established by injection of 4T1 cells into the mammary fat pad of Nu/J mice were administered two doses of (1 × 106) salt induced Th17 cells on day 7 and day 12, post-tumor implantation. By day 28, the high salt induced Th17 cells cohort demonstrated significantly reduced tumor growth (97 ± 34 mm3 vs 512 ± 91 mm3, untreated control, p&lt;0.05) and lung metastasis. However, no effect on tumor growth was noted when these 4T1 sensitized high salt treated Th17 cells were injected into Nu/J mice with prostrate (RM1) and lung tumors (KLN205), thus suggesting that the specificity of salt induced Th17 cells to breast tumors. Similarly, in vitro high salt mediated differentiation of Th17 cells when co-treated with heat killed RM1 and KLN205 cancer cells were able to induce respective murine tumor regression. Mechanistic studies demonstrated that the high salt induction to the Th17 phenotype was mediated by the tonicity-dependent transcription factor, TonEBP/NFAT5. The shRNA-based knockdown of TonEBP abrogated the induction of the Th17 phenotype and expression of proinflammatory cytokines IL-17, IL-1β and IL-6. Taken together, our data suggests that high salt mediated in vitro differentiation of Th17 cells could induce tumor specific anticancer CD4+T lymphocytes, which may give rise to a cell-based anticancer immunotherapy application.
Citation Format: Suneetha Amara, Pooja Yenuga, Roy Zent, Venkataswarup Tiriveedhi. NFAT5/TonEBP mediated anti-tumor efficiency of high salt activated CD4+T lymphocytes [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr B45.
Abstract B48: PBRM1 loss promotes resistance to immunotherapy in RCC
Authors: Liu Xian-De , Kong Wen , Hoang Anh , Zhang Xuesong , Zhou Lijun , Pilie Patrick G. , Isgandrova Sevinj , Moczygemba Margie M. , Jonasch Eric 
Published: June 2021

Abstract
PBRM1 is a subunit of a SWI/SNF chromatin remodeling complex, and more than 30% of clear cell RCCs show PBRM1 mutations. The function of PBRM1 in tumor immune microenvironment, tumor prognosis and response to immune checkpoint therapies still remain unclear. Here we found that Pbrm1 knockout in mouse Renca RCC cells decreased the activity of IFNγ-STAT1 signaling pathway and consequently the expression of chemokines that recruit effector CD8+ T cells. Pbrm1 deficient murine RCC tumors showed reduced infiltration of CD8+ T cells, which was associated with less PD-1 expression. Pbrm1 deficient tumors demonstrated longer latency but they were more resistant to anti-PD1 treatment. This study provided mechanistic insights and therapeutic guideline to manage ccRCC associated with PBRM1 inactivation.
Citation Format: Xian-De Liu, Wen Kong, Anh Hoang, Xuesong Zhang, Lijun Zhou, Patrick G. Pilie, Sevinj Isgandrova, Margie M. Moczygemba, Eric Jonasch. PBRM1 loss promotes resistance to immunotherapy in RCC [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr B48.
Abstract B53: Immunomodulatory effect of prostaglandin dehydrogenase in metastatic colon cancer
Authors: Satapathy Shakti R. , Sjolander Anita 
Published: June 2021

Abstract
Cyclooxygenase-2, the key player in the biosynthesis of prostaglandin-E2 (PGE2) is often upregulated in colon cancer (CC). TNF-α, the main regulator of COX-2 and mPGES-1, contributes to the increased synthesis of PGE2, which is inhibited by overexpressed prostaglandin dehydrogenase (15-PGDH), a tumor suppressor playing major role in PGE2 catabolism but often downregulated in CC. Interestingly, CC patients expressing high levels of cysteinyl leukotriene receptor-2 (CysLT2R) have good prognosis and therefore, we investigated a potential link between CysLT2R-signaling and 15-PGDH in metastatic CC. Elevation of 15-PGDH expression by LTC4, a CysLT2R ligand, exhibited anti-tumor activity in colon cancer cells with significant phosphorylation of β-catenin with concurrent activation of CASPASE-3 and dramatic down-regulation of TNF-α mRNA expression in two different colon cancer cells. Colony-stimulating factor 1 (CSF-1) is a key regulator of macrophage differentiation that supports the protumorigenic role of tumor-associated macrophages (TAMs). We observed high CSF-1 in metastatic colon cancer with low CysLT2R expression, which is correlated with high level of CD-8+ T-cells and CD-163+ TAMs. CC cell lines produced high amount of CSF-1 when co-cultured with CC-specific CD-8+ T-cell or exposed to T-cell derived cytokines in vitro and exhibited significant reduction with LTC4 stimulation or 15-PGDH overexpression. Furthermore, longer use of 15-PGDH led to downregulation in the PD-L1 in a time-dependent manner. Combination of anti-CSF-1, anti-PD-1 and LTC4 exhibited significant reduction in CC tumor rich in macrophages. Blockade of PD-1/PD-L1 axis also facilitated upregulation of IFN-γ in γδ-T cells. Hence restoration of 15-PGDH expression through CysLT2R-signaling promotes immunomodulatory effect, indicating a promising therapeutic alternative for metastatic CC with high TAM infiltration.
Citation Format: Shakti R. Satapathy, Anita Sjolander. Immunomodulatory effect of prostaglandin dehydrogenase in metastatic colon cancer [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr B53.
Abstract B72: Lineage specifiers SOX2 and NKX2-1 inversely regulate tumor cell fate and neutrophil recruitment in lung cancer
Authors: Mollaoglu Gurkan , Jones Alex , Wait Sarah , Mukhopadhyay Anandaroop , Jeong Sangmin , Arya Rahul , Camolotto Soledad , Mosbruger Timothy , Stubben Chris , Conley Christopher , Bhutkar Arjun , Vahrenkamp Jeffery , Berrett Kristofer , Cessna Melissa , Lane Thomas , Witt Benjamin , Salama Mohamed , Gertz Jason , Jones Kevin , Snyder Eric , Oliver Trudy 
Published: June 2021

Abstract
The major types of non-small cell lung cancer, squamous cell carcinoma and adenocarcinoma, have distinct tumor immune microenvironments. Understanding the mechanisms underlying these differences is of particular importance given the success and current limitations of immunotherapy. We developed multiple mouse models of lung cancer to demonstrate that NKX2-1 potently suppresses SOX2-driven squamous tumorigenesis by repressing adeno-to-squamous transdifferentiation. Furthermore, SOX2 recruits, whereas NKX2-1 suppresses, tumor-associated neutrophils (TANs) at least partly through inverse regulation of the chemoattractant CXCL5/6. Single-cell RNA sequencing revealed that TANs exhibit tumor-promoting features and distinct gene expression profiles compared to blood neutrophils. Finally, TANs cooperate with squamous-associated genetic alterations to promote squamous tumors. These data reveal how transcription factors with key functions in normal development dictate not only cancer cell identity but also distinct tumor immune microenvironments.
Citation Format: Gurkan Mollaoglu, Alex Jones, Sarah Wait, Anandaroop Mukhopadhyay, Sangmin Jeong, Rahul Arya, Soledad Camolotto, Timothy Mosbruger, Chris Stubben, Christopher Conley, Arjun Bhutkar, Jeffery Vahrenkamp, Kristofer Berrett, Melissa Cessna, Thomas Lane, Benjamin Witt, Mohamed Salama, Jason Gertz, Kevin Jones, Eric Snyder, Trudy Oliver. Lineage specifiers SOX2 and NKX2-1 inversely regulate tumor cell fate and neutrophil recruitment in lung cancer [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2018 Nov 27-30; Miami Beach, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(4 Suppl):Abstract nr B72.