bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 3256: TIGIT humanized BALB/c mouse: A novel animal model for preclinical studies of human TIGIT antibodies
Authors: Ju Cunxiang , Zhang Mingkun , Yang Xiaoliu , Li Song , Sun Hongyan , Li Shuai , Tang Jing , Zhao Jing , Gao Xiang 
Published: September 2020

Abstract
TIGIT is an immune-checkpoint receptor mainly expressed on activated and memory T cells, regulatory T cells (Tregs), and NK cells. Engaged with CD155 and CD112, TIGIT can transmit an inhibitory signal that negatively regulate the cell functionality. TIGIT blockade antibodies that release the inhibitory signals and direct potent tumor killing are currently under active development. However, animal models appropriate for preclinical evaluation of human TIGIT antibodies are still largely unmet. To solve this problem, we established a TIGIT humanized mouse model (hTIGIT) in which the extracellular domain of mTIGIT was replaced with human counterparts while the trans-membrane and cytoplasmic domain kept intact. These hTIGIT mice express similar level of chimeric TIGIT as compared to mTIGIT in wildtype mice. Surprisingly, the growth of subcutaneously engrafted CT26 tumor in BALB/c-hTIGIT mice, but not MC38 tumor in B6-hTIGIT mice, was strongly inhibited when treated with human TIGIT antibody (anti-TIGIT). TILs analysis on CT26 engrafted BALB/c-hTIGIT revealed significantly higher levels of intra-tumoral NK and Treg cells, and more interesting, Treg was remarkably deleted after anti-TIGIT intervention. Furthermore, Fc mutation that blocks ADCC effect completely abolished its therapeutic activity. These data suggested that tumor infiltrated Treg clearance by ADCC may contribute to the tumor inhibition observed in BALB/c-hTIGIT model. Taken together, BALB/c-hTIGIT mouse is a novel non-human animal model that can recapitulate the tumor environment and appropriate for direct preclinical efficacy study of human TIGIT antibodies.
Citation Format: Cunxiang Ju, Mingkun Zhang, Xiaoliu Yang, Song Li, Hongyan Sun, Shuai Li, Jing Tang, Jing Zhao, Xiang Gao. TIGIT humanized BALB/c mouse: A novel animal model for preclinical studies of human TIGIT antibodies [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 3256.
Abstract 3260: The preclinical characterization of CS1001, an anti-PD-L1 IgG4 monoclonal antibody and its activity beyond T cell regulation
Authors: Zhang Juan , Li Zhenhu , Tang Liang , Liu Linlin , Ren Zhaoxiang , Ma Jingshu , Shi Qingmei , Bao Yuanwu , Lu Liang , Zheng Yong , Yang Baotian , Li Jing , Wang Xinzhong Jon 
Published: September 2020

Abstract
CS1001 is a high-affinity, fully human programmed death ligand-1 (PD-L1) blocking IgG4 monoclonal antibody. So far three therapeutic anti-PD-L1 antibodies (atezolizumab, avelumab, durvalumab) have been approved by US FDA in different cancer indications. CS1001 selectively bound to PD-L1 and blocked PD-L1/PD-1 ligation. The crystal structure of CS1001 complexed with human PD-L1 solved at 2.3Å revealed that CS1001 bound perpendicularly to PD-L1 and the binding epitope region well overlapped with the hPD1-binding region. In the Mixed Lymphocyte Reaction (MLR) assay, CS1001 effectively induced the proliferation of CD4+ T lymphocytes and the production of interferon-γ (IFN-γ) and interleukin-2 (IL-2). CS1001 employs IgG4 isotype and lacks antibody-dependent cellular mediated cytotoxicity (ADCC) or complement-dependent cytotoxicity (CDC). Furthermore, the in vivo efficacy of CS1001 in inhibiting tumor growth was demonstrated in the subcutaneous MC38-hPD-L1 murine colon carcinoma (murine MC38 cells expressing human PD-L1) in human PD-1 knock-in mouse (Biocytogen) model. In another dual-humanized animal model, i.e. PD-1/PD-L1 dual knock-in mice implanted with MC38-hPD-L1 tumor (Biocytogen) where human PD-L1 expressed in both tumor and host system, it is interestingly noticed that CS1001 not only enhanced the cytotoxic T cell/regulatory T cell ratio, but also significantly upregulated M1 macrophage & down-regulated MDSC population, suggesting that anti-PD-L1 antibody may play the pro-anti-tumor immune response through modulating myeloid cells that also express PD-L1, thus a non-ADCC/CDC antibody design could be beneficial. CS1001 is currently explored clinically in 5 registration trials as monotherapy or in combination with standard of care therapies. CS1001 monotherapy or combo with chemotherapy or targeted therapy were safe and well tolerated. CS1001 demonstrated promising efficacy in multiple tumor types and support full development of CS1001 as mono/combo therapy for multiple indications in ongoing and planned clinical trials including cHL, ENKTL, GC, EC, and NSCLC.
Citation Format: Juan Zhang, Zhenhu Li, Liang Tang, Linlin Liu, Zhaoxiang Ren, Jingshu Ma, Qingmei Shi, Yuanwu Bao, Liang Lu, Yong Zheng, Baotian Yang, Jing Li, Xinzhong Jon Wang. The preclinical characterization of CS1001, an anti-PD-L1 IgG4 monoclonal antibody and its activity beyond T cell regulation [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 3260.
Abstract 3264: CRISPR-Cas9 library screen in primary T cells to identify cancer immunotherapeutic targets
Authors: Yue Yangbo , Li Qian 
Published: September 2020

Abstract
Background: Immunotherapy, especially checkpoint blockers targeting programmed cell death protein 1 (PD-1) pathways, has transformed cancer treatment. Current checkpoint blockers are limited by low response rate, side effect and treatment relapse. An efficient and high-throughput screen platform in primary immune cells will accelerate the identification of key regulators in the immune response to tumor. New targets identified from the screen will be validated in in vitro and in vivo models that recapitulate key components of tumor-immune interaction.
Results: We developed a CRISPR-Cas9 genome targeting system that can achieve efficient gene disruption in primary CD8+T cells isolated from mouse (~60%) or human (~70%). We have applied this method to a pooled CRISPR library screen for key modulators of T cell-induced cytotoxicity to cancer cells in vitro and in vivo. This library contains sgRNAs targeting nearly all membrane proteins expressed in both murine and human T cells. In our in vitro model, cancer cells expressing chicken ovalbumin (OVA) were co-cultured with OVA-specific CD8+T cells isolated from OT-I transgenic mice. The proliferation and function of CD8+ T cell were damped by tumor cells in an antigen dependent way. In our in vivo model, OVA-specific CD8+T cells were transplanted into C57BL/6 mice implanted with OVA-expressing tumor. The accumulation, proliferation and function dynamics of transplanted CD8+T cells were monitored in tumors. They infiltrated into tumor in 3 days, substantially decreased in number in the following 4 days, and then continuously increased. Importantly, most CD8+T cells (~70%) in tumor were CD107a negative, which means they were non-functional.
Summary: We have established a high-throughput platform for identification of membrane proteins in primary CD8+ T cells to regulate T cell proliferation and function in tumor microenvironment.
Citation Format: Yangbo Yue, Qian Li. CRISPR-Cas9 library screen in primary T cells to identify cancer immunotherapeutic targets [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 3264.
Abstract 3269: Ablation of Cbl-b gene function leads to increased activation and resistance to immunosuppression in human primary T lymphocytes
Authors: Parmantier Eric , Kalouche Georges , Soulard Clara , Lanneau Christophe , Boisrobert-Blais Sophie , Nicolazzi Céline , Orsini Cécile 
Published: September 2020

Abstract
Purpose: The role of Cbl-b as an essential modulator of T cell activation has been widely documented, particularly in mouse studies. To substantiate the effects of Cbl-b ablation in human T cells, gene editing conditions were optimized, and gene KO efficiency was evaluated along with T cell response to stimulatory antibodies.
Experimental design: Non-preactivated human primary T cells obtained from several donors were electroporated with the CRISPR/Cas9-gRNA ribonucleoprotein complex targeting CBLB gene or controls. Cells were then activated in presence of anti-CD3 and anti-CD28 antibodies with or without the immunosuppressive factors PGE2 or TGFβ. Gene editing efficiency was measured using targeted NGS technology and cytokine release (IL2, IFNγ, TNFα), membrane activation markers (CD25, CD69) and cell proliferation were evaluated at various timepoints.
Results: Initial studies showed moderate gene editing efficiencies with on average 45% and 25% of out-of-frame mutations using 2 gRNAs targeting different regions of CBLB gene and were correlated with increased IL-2 release. By optimizing gene editing experimental conditions, out-of-frame mutations in CBLB gene reached more than 70% and were associated with higher levels of secreted IL2, IFNγ and TNFα early after T cell stimulation and increased CD25 membrane expression at later timepoints, compared to controls. Furthermore, CBLB gene-edited T cells were less susceptible to PGE2- and TGFβ-mediated inhibition of cell proliferation.
Conclusion: The efficient gene editing in human non-preactivated T cells, through the delivery of the CRISPR/Cas9-gRNA ribonucleoprotein complex, confirms that Cbl-b acts as a negative regulator of T cell activation and further validates its role in transducing immunosuppressive environmental cues.
Citation Format: Eric Parmantier, Georges Kalouche, Clara Soulard, Christophe Lanneau, Sophie Boisrobert-Blais, Céline Nicolazzi, Cécile Orsini. Ablation of Cbl-b gene function leads to increased activation and resistance to immunosuppression in human primary T lymphocytes [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 3269.
Abstract 3300: Association of molecular characteristics with survival in advanced non-small cell lung cancer patients treated with checkpoint inhibitors
Authors: Zhao Dan , Mambetsariev Isa , Li Haiqing , Chen Chen , Fricke Jeremy , Fann Patricia , Kulkarni Prakash , Xing Yan , Lee Peter , Bild Andrea , Massarelli Erminia , Koczywas Marianna , Reckamp Karen , Salgia Ravi 
Published: September 2020

Abstract
Objectives: Immune checkpoint inhibitors (ICIs) have changed the landscape of lung cancer therapy. However significant proportions of patients have primary or acquired resistance to ICIs. Molecular characterization is critical for patient selection and overcoming resistance to checkpoint inhibitors. The purpose of this study is to investigate the molecular characteristics associated with ICIs outcomes in advanced non-small cell lung cancer (NSCLC) patients.
Materials and methods: All advanced stage NSCLC patients at City of Hope who received ICIs (pembrolizumab, nivolumab, atezolizumab, and durvalumab) were identified retrospectively. Overall survival (OS, from the start of the ICIs), Pathology and information on genomic alterations (GAs) including next-generation sequencing (NGS) data, tumor mutation burden (TMB), and Programmed death-ligand 1 (PD-L1) levels were collected. Chi-square and Fisher's exact test, Log-rank test were used for comparison of demographics, and survival curves respectively. Univariate and multivariate COX proportional hazards model was used for survival analysis.
Results: 346 NSCLC patients were identified. Univariate and multivariate analysis found the association of OS with PD-L1 level ≥50% (Hazard ratio [HR], 0.19; 95% confidence interval [CI], 0.06-0.59; P&lt;0.01), EGFR (HR 7.38; 95% CI, 1.15-47.42; P&lt;0.05), and TET2 (HR 0.15; 95% CI, 0.03-0.90; P&lt;0.05). The median OS was not reached [NR] for the 12 patients who had genomic alterations (GAs) in TET2 (12/108, 11%) versus (vs) 11.5 months in TET2 negative patients (98/108, 89%). Interestingly, GAs in TET2 and FANCA were mutually exclusive and patients who had GAs in FANCA gene (6%) had shorter OS (5.5 months vs 14.5 months, Log-rank test, P&lt;0.05).
Conclusions: We described the clinical and molecular features of NSCLC patients treated with ICIs. The association of GAs in TET2 with longer OS and its mutual exclusivity with FANCA GAs were insightful for developing novel therapeutic strategies to improve ICIs outcomes in NSCLC.
Keywords: Lung cancer, molecular, next-generation sequencing (NGS), immune checkpoint inhibitors, TET2, FANCA, PD-L1, TMB, immunotherapy
Citation Format: Dan Zhao, Isa Mambetsariev, Haiqing Li, Chen Chen, Jeremy Fricke, Patricia Fann, Prakash Kulkarni, Yan Xing, Peter Lee, Andrea Bild, Erminia Massarelli, Marianna Koczywas, Karen Reckamp, Ravi Salgia. Association of molecular characteristics with survival in advanced non-small cell lung cancer patients treated with checkpoint inhibitors [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 3300.
Abstract 3311: B cell like neutrophil found in peripheral blood of melanoma patients
Authors: Meyer Melissa A. , Dinh Huy Q. , Zhu Yanfang , Liang Shu , Seumois Gregory , Vijayanand Pandurangan , Catz Sergio D. , Hedrick Catherine C. 
Published: September 2020

Abstract
An expansion of neutrophils often marks cancer. To date, neutrophils are assumed to be a relatively homogenous population, but recent studies describe both pro- and anti-tumor functions in neutrophils. This suggests there is more heterogeneity in neutrophils than previously appreciated. To better understand and target neutrophil functions in cancer, we must dissect neutrophil heterogeneity and how it changes from health to disease. To this end, we employed single-cell transcriptome technology to profile immature neutrophils from bone marrow of healthy individuals. Intriguingly, we identified a new neutrophil subset that expresses several B cell markers, including CD79a/b, components of the B cell receptors and PAX5, a lineage-specific transcriptional factor. We termed this population the BNeut. Using flow cytometry, we found that BNeuts are confined to the bone marrow of healthy individuals but expand into the blood of melanoma patients at an early stage, suggesting BNeuts might be a biomarker for disease. Additionally, we find BNeuts in the mouse models of different cancer types, including breast and lung carcinoma. The BNeut appears and functions more similar to a neutrophil than a B cell. BNeuts possess a neutrophil-like transcriptional profile, large cytoplasm with segmented nucleus, and produce ROS and NETs. Using imaging, we show that the BNeuts are single cells co-expressing both CD66b and CD79b, and lack the B cell surface marker CD19. To understand why neutrophils might use a B cell program, we explored different B cell functions including antigen presentation, a function that is usually absent from neutrophils. We show BNeuts are excellent at phagocytosis, including uptake of tumor cells. Further, BNeuts have increased expression of antigen presentation-related genes compared to other neutrophils and can modulate CD4+ T cell responses. Together, we have identified a novel neutrophil subset expressing B cell markers that is preferentially expanded in the blood of melanoma patients and poised to control T cell responses during disease.
Citation Format: Melissa A. Meyer, Huy Q. Dinh, Yanfang Zhu, Shu Liang, Gregory Seumois, Pandurangan Vijayanand, Sergio D. Catz, Catherine C. Hedrick. B cell like neutrophil found in peripheral blood of melanoma patients [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 3311.
Abstract 3323: In situ multiplex analysis of resident microglia and infiltrating macrophages in glioblastoma
Authors: Goulange Nicolas , Finan-Marchi Amanda , Tliba Maroua , Motte Manon , Estermann Fanny , Vernay Alexandre , Coton Jean-Philippe , Burrer Renaud 
Published: September 2020

Abstract
Glioblastoma mutliforme (GBM) is the most malignant primary brain tumor. Resident microglia and peripheral infiltrating macrophages account for up to half of the non-neoplastic cells in a GBM. These tumor-associated macrophages have been implicated in proliferation, angiogenesis, and immunosuppression in GBM and can influence the efficacy of chemo-, radio-, and immunotherapies. However, certain cancer specific interactions have been associated with either microglia or macrophages, necessitating an approach that can delineate the two populations. Multiplex immunofluorescence offers a technical advantage that allows for the profound phenotyping of cells in the tumor microenvironment as well as their spatial organization. We have designed a multiplex immunofluorescence protocol to differentiate microglia and infiltrating M1/M2 macrophages in GBM in situ. Human GBM tissues were investigated with a multiplex panel consisting of GFAP, TMEM119, CD68, c-maf, and CD163. After multi-spectral acquisition, the microglia and macrophage populations could be easily phenotyped and localized in all of the tissues examined. Microglia and peripherally recruited M1 and M2 macrophages were quantified. The spatial distribution of the populations within the tumor core, edge, or margin was evaluated. The approach presented here demonstrates the power of multiplex immunohistochemistry in the phenotyping and spatial analysis of resident and recruited immune cell populations on a single tissue section and the potential application of this method in clinical studies.
Citation Format: Nicolas Goulange, Amanda Finan-Marchi, Maroua Tliba, Manon Motte, Fanny Estermann, Alexandre Vernay, Jean-Philippe Coton, Renaud Burrer. In situ multiplex analysis of resident microglia and infiltrating macrophages in glioblastoma [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 3323.
Abstract 3331: Role of innate immune cells in the development of vessel co-opting CRC liver metastases
Authors: Mayer Thomas Z. , Kim Diane H. , Rada Miran , Petrillo Stephanie , Lazaris Anthoula , Metrakos Peter 
Published: September 2020

Abstract
Approximatively 50 % of patients who undergo resection for primary colorectal cancer will develop liver metastases. Liver metastases present as two major histopathological growth patterns (HGP) the desmoplastic and the replacement HGP. In the desmoplastic HGP, the cancer cells are surrounded by a desmoplastic stromal ring preventing their contact with the normal liver. In the replacement HGP, the cancer cells infiltrate the normal liver and replace hepatocytes near the tumour periphery. We have found that the desmoplastic HGP tumors derive their blood supply through angiogenesis while the replacement HGP tumors are non-angiogenic and co-opt the blood vessel of the liver they invade. Furthermore, we have published that patients under chemotherapy presenting with a vessel co-opting phenotype have a worse pathological response and five-year overall survival compared to patients presenting with angiogenic liver metastases. Their prognosis is worse when treated with bevacizumab an anti-VEGF antibody used alongside chemotherapy. CRCLM are considered immunologically cold lesions, with low numbers of infiltrating T-cells, and thought to be unlikely to benefit from immunotherapies. We have recently found that neutrophils and macrophages but not lymphocytes infiltrate vessel co-opting lesions to a greater extent than angiogenic lesions. Using flow cytometry and the Nanostring GeoMx spatial protein profiling platform capable of detecting up to 96 proteins simultaneously on FFPE tissue slices, we established the immunoprofile of immune cells recruited to angiogenic or vessel co-opting CRCLM lesions in chemonaive and treated patients. Many studies have demonstrated that neutrophils and macrophages play an important role in tumor progression, modification of the ECM, angiogenesis, and immunosuppression. We hypothesize that innate immune cells can facilitate blood vessel co-option of CRCLM lesions and contribute to an immunosupressive environment favorable to tumor growth. Fully understanding the role of the innate immune system in the developmend of vessel co-opting CRCLM tumors could allow for the development of immunotherapies capable of converting vessel co-opting lesions into angiogenic lesions that are more successfully treated with chemotherapy and anti-angiogenic therapies.
Citation Format: Thomas Z. Mayer, Diane H. Kim, Miran Rada, Stephanie Petrillo, Anthoula Lazaris, Peter Metrakos. Role of innate immune cells in the development of vessel co-opting CRC liver metastases [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 3331.
Abstract 3374: Development of novel and improved monoclonal antiMUC16 antibodies for the targeted therapy of ovarian cancer
Authors: Laster Ian , Yeku Oladapo , Spriggs David 
Published: September 2020

Abstract
There is a need for the development of better targeted therapies in the treatment of ovarian cancer. Monoclonal antibodies directed towards MUC16, a diagnostic and prognostic marker for ovarian cancer, with improved selectivity and specificity would be an instrumental component in the construction of novel methods of drug delivery and immunotherapies. C57BL/6 mice were immunized with various MUC16 peptides and truncated MUC16 constructs to extend the scope of MUC16 epitopes within the proximal COOH portion of the retained elements. Three rounds of hybridomas were made from harvested murine splenocytes, and subsequent rounds of peptide-based ELISA and cell-based flow cytometry were performed to select the most promising subclones from each of the fusions. Over 50 hybridomas producing antibodies against MUC16 have been identified and screened for reactivity with MUC16 peptide sequences and native, full-length MUC16 protein presented on the surface of ovarian cancer cell line cells. The antibodies were isotyped, and 10 have been selected for initial characterization. Non-overlapping epitopes were mapped via sequential and tandem peptide-based ELISA. With improved selectivity and specificity, these monoclonal antibodies will be used in the construction of antibody drug conjugates (ADCs) as potential targeted therapies in the treatment of ovarian cancer. Efficacy testing of the candidate antibodies in Matrigel invasion and direct growth inhibition assays is underway. Comparative effectiveness of the binding, internalization, and killing by ADCs in ovarian cancer cell lines will be presented. Antibodies against key MUC16 epitopes may have value in the development of antigen directed therapy.
Citation Format: Ian Laster, Oladapo Yeku, David Spriggs. Development of novel and improved monoclonal antiMUC16 antibodies for the targeted therapy of ovarian 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 3374.