bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract B100: An emerging model for cancer development from a tumor microenvironment perspective in mice and humans
Authors: Yamaguchi Ryuji , Perkins Guy 
Published: March 2020

Abstract
Introduction: We constructed a phylogenic tree of TME based on the transcriptomes from melanoma biopsy samples. From these data, we developed a model that fits the clinical observations in various solid cancer. However, clinical data on the development of TME are like snapshots of cancer at discrete points and thus represent partial views of a dynamic process. It is a model based on an inductive argument. To make the argument more deductive, we examined whether the model fits observations of murine cancer progression. There are only a few dozen mouse cancers in which cancer development takes place reliably and reproducibly in mice with intact immune system. These cancer models in mice augmented the developmental model of TME based on the clinical data.
Summary: The tumor development is initiated by a slowly growing, nearly homogeneous colony of cancer cells that can evade detection by the cells’ innate mechanism of immunity such as natural killer (NK) cells (1st Stage; Colonization). Subsequently, the colony develops into a tumor filled with lymphocytes and stromal cells, releasing proinflammatory cytokines, growth factors, and chemokines (2nd Stage; Lymphocyte Infiltration). Cancer progression proceeds to a well-vesiculated silent tumor releasing no inflammatory signal, being nearly devoid of lymphocytes (3rd Stage; Silenced). Eventually some cancer cells within a tumor undertake epithelial-to-mesenchymal transition (EMT), which leads to cancer metastasis (4th Stage; EMT). If a circulating metastasized cancer cell finds a niche in a new tissue and evades detection by NK cells, it can establish a new colony in which very few stromal cells are present (5th Stage; Metastasis), which is much like a colony at the first stage of development. At every stage, cancer cells influence their own TME and in turn, the TME influences the cancer cells contained within, either by direct interaction between cancer cells and stromal cells or through exchange of cytokines.
Conclusion: There seem to be aspects of cancer development that are independent of cell types and DNA mutations. The hypothesis is that the aspects that are governed solely by the TME can be discovered. Therefore, a productive approach would be to study a particular solid cancer and learn when and how a tumor recruits lymphocytes, fibroblasts, and macrophages to build a Stage 2 environment, and when and how the environment is changed into Stage 3 and Stage 4, and then test how chemotherapeutics and immunotherapies would affect these environments. It is anticipated that most of the knowledge gained would be applicable to essentially any other solid cancer.
Citation Format: Ryuji Yamaguchi, Guy Perkins. An emerging model for cancer development from a tumor microenvironment perspective in mice and humans [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B100.
Abstract B102: Epithelium-derived cytokines in breast carcinogenesis
Authors: Kroon Sanne , Dempsey Kaitlin , Boieri Margherita , Demehri Shawn 
Published: March 2020

Abstract
Novel approaches in cancer immunotherapy have led to effective therapeutics against late-stage cancers. However, the role of the immune system in protection against early-stage cancers remains uncertain. We have previously discovered that thymic stromal lymphopoietin (TSLP) blocks early stages of breast cancer development through activation of CD4+ T cells. TSLP is an epithelium-derived danger signal that plays a key role in initiating an immune response upon cell damage and stress. The aim of this study is to investigate the potential involvement of other epithelial-derived cytokines in the activation of an immune response against premalignant breast lesions. To identify these signals, we analyzed the expression of a wide range of epithelium-derived cytokines in normal mammary glands, premalignant lesions, and late-stage tumors of MMTV-PyMT (PyMTtg) and K14-Cre, Brca1f/f, p53f/f mouse models. These mice spontaneously develop breast tumors that resemble human luminal and basal-like breast cancers, respectively. Of the cytokines examined, IL-1a was highly expressed in premalignant lesions compared to mammary glands and tumors. Additionally, IL-12p40 was upregulated in both early and late stages of breast cancer compared to normal mammary gland. Other cytokines, like IL-7, IL-11, and IL-24, were highly expressed in the mammary gland, but their expression was lost during breast tumorigenesis. In conclusion, we identified upregulation of IL-1a and IL-12p40 in early-stage breast cancer, suggesting a role for these cytokines in inducing antitumor immunity in the breast. Furthermore, we demonstrate selection against expression of IL-7, IL-11, and IL-24 during the process of cancer initiation and promotion, suggesting a role in normal mammary gland homeostasis and possibly immunity against breast carcinogenesis. Taken together, we have identified potential novel therapeutic targets that can be leveraged for breast cancer immunoprevention.
Citation Format: Sanne Kroon, Kaitlin Dempsey, Margherita Boieri, Shawn Demehri. Epithelium-derived cytokines in breast carcinogenesis [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B102.
Abstract B12: Exploiting the zebrafish to study lymphocyte infiltration in MYCN-driven neuroblastoma
Authors: Qin Xiaodan , Lam Andrew , Zhang Xike , Hurlstone Adam , Feng Hui 
Published: March 2020

Abstract
Application of tumor immunotherapy has achieved an unprecedented success in patients with hematopoietic malignancies. However, it remains challenging to treat the majority of solid tumors with immunotherapy due to low lymphocyte infiltration, treatment resistance, and immunosuppressive tumor microenvironment. Improving the clinical efficacy of immunotherapy in solid tumors requires a deeper understanding of immune evasion. Neuroblastoma is the most common extracranial tumor in children and is responsible for ~15% of childhood cancer-related deaths. MYCN is a member of the MYC oncogene family, and its aberrant expression in neuroblastoma predicts aggressive disease and poor prognosis. This largely results from the low infiltration rates of cytotoxic lymphocytes in MYCN-amplified neuroblastoma. Elucidation of the mechanism by which MYCN suppresses antitumor response in the neuroblastoma microenvironment will provide useful information to guide immunotherapy. Here we generated a compound transgenic zebrafish, Tg(dβh:MYCN;dβh:EGFP;lck:EGFP;CD4:mCherry), in which lymphocytes and tumor cells are differentially fluorescently labeled. We first monitored the infiltration of mCherry-labeled CD4+ T cells in EGFP-positive MYCN-overexpressing premalignant neural crests at 7, 14, and 21 days post fertilization (dpf). We found that at day 14 and 21, MYCN-overexpressing premalignant neural crests can attract a significantly higher number of lymphocytes, compared to control neural crests without MYCN overexpression. Interestingly, we also found the increased number of infiltrated T cells was MYCN dose dependent by using low MYCN-expressing transgenic fish, Tg(dβh:MYCN;dβh:mCherry;lck:EGFP). To determine if T-cell development is impacted, we imaged the thymus of MYCN-overexpressing or control fish at day 7, 14, and 21 dpf. We found that fluorescent intensity of thymus is significantly higher in MYCN-overexpressing fish compared to control fish. Taken together, our study identified MYCN-overexpressing premalignant neural crests can not only affect T-cell development but also attract T cells to disease site. We will perform further experiments to understand how and why MYCN-overexpressing premalignant neural crests impact T-cell development and which population of T cells is attracted to disease site.
Citation Format: Xiaodan Qin, Andrew Lam, Xike Zhang, Adam Hurlstone, Hui Feng. Exploiting the zebrafish to study lymphocyte infiltration in MYCN-driven neuroblastoma [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B12.
Abstract B19: Cowpea mosaic virus stimulates antitumor immunity through recognition by MYD88-dependent signaling of multiple Toll-like receptors
Authors: Mao Chenkai , Beiss Veronique , Shukla Sourabh , Steinmetz Nicole , Fiering Steven 
Published: March 2020

Abstract
Cowpea mosaic virus (CPMV), a non-enveloped plant virus, and empty CPMV (eCPMV), a virus-like particle composed of CPMV capsid, have demonstrated strong activation of neutrophils, suppression of primary tumor growth, and durable systemic antitumor immunity in murine models with no side effects when administered intratumorally as an in situ vaccine. However, it is not known how immune cells recognize these nanoparticles. In this study, CPMV and eCPMV exhibited overlapping yet distinctive recognition patterns and immunostimulatory profiles. Specifically, CPMV generated stronger selective induction of cytokines and chemokines in naive splenocytes and exhibited more potent antitumor efficacy compared to eCPMV. We found that MyD88 is required for both CPMV- and eCPMV-elicited immune responses. Screening with HEK-BlueTM mouse and human Toll-like receptor (TLR) assays along with response and efficacy studies in corresponding TLR-/- mice indicated the recognition of both CPMV and eCPMV by MyD88-dependent TLR2 and TLR4 as well as recognition of CPMV by TLR7. Furthermore, the studies revealed that TLR2 and TLR4 are complementary to each other in recognizing the capsid of either particle in vivo and in vitro. We further confirmed that secretion of type I interferons (IFNs) by CPMV is critical to its stronger efficacy, which is dependent on the binding between TLR7 and the encapsulated single-stranded RNAs (ssRNAs) of CPMV. These findings link efficacy with molecular recognition and provide rationale for developing more potent viral particles as immunotherapeutic vaccines to cancer.
Citation Format: Chenkai Mao, Veronique Beiss, Sourabh Shukla, Nicole Steinmetz, Steven Fiering. Cowpea mosaic virus stimulates antitumor immunity through recognition by MYD88-dependent signaling of multiple Toll-like receptors [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B19.
Abstract B26: Prorapeutic vaccination against shared antigens induced in future tumors
Authors: Garrido Greta , Schrand Brett , Levay Agata , Rabasa Ailem , Ferrantella Anthony , Da Silva Diane , D’Eramo Francesca , Marijt Koen , Daley-Bauer Lisa , Kwon Deukwoo , Kast Martin , Mocarski Ed , Dudeja Vikas , van Hall Thorbald , Gilboa Eli 
Published: March 2020

Abstract
Vaccination of patients against mostly patient-specific neoantigens expressed in concurrent and recurring tumors, or tumors developing in individuals at high risk of cancer, is posing major challenges in terms of which antigens to target and is limited to a subset of patients expressing neoantigens in their tumors. Here we describe a broadly applicable vaccination strategy against shared antigens that are experimentally induced in tumor cells by downregulation of the peptide transporter TAP. Presentation of the new epitopes in tumor cells is achieved using a siRNA to downregulate TAP mRNA, which is targeted to tumor cells in situ by conjugation to a broad-range nucleolin binding oligonucleotide aptamer ligand. An immune response against the TAP downregulation-induced antigens presented by the tumor cells is elicited by downregulation of TAP in resident dendritic cells via conjugation to a CpG oligonucleotide. Vaccination against experimentally induced antigens is particularly suitable for vaccination against tumors that recur after a long period of remission, or tumors that will develop in individuals at high risk of cancer, because it eliminates the uncertainties of which neoantigens are expressed in the future tumors. Vaccination against the TAP downregulation-induced antigens was more effective than vaccination against tumor-resident, mutation-generated, shared neoantigens, was devoid of measurable toxicity, and inhibited the growth of future tumors in models of recurrence and premalignant disease. Human CD8+ T cells stimulated with TAPlow dendritic cells elicited a polyclonal CD8+ T-cell response that recognized tumor cells with experimentally reduced TAP expression, as well as CMV and EBV infected cells that naturally downregulate TAP expression. Vaccination against TAP downregulation-induced antigens overcomes the main limitations of vaccinating against mostly unique tumor-resident neoantigens and could represent a common vaccination strategy for patients with concurrent, recurrent, and future tumors.
Citation Format: Greta Garrido, Brett Schrand, Agata Levay, Ailem Rabasa, Anthony Ferrantella, Diane Da Silva, Francesca D’Eramo, Koen Marijt, Lisa Daley-Bauer, Deukwoo Kwon, Martin Kast, Ed Mocarski, Vikas Dudeja, Thorbald van Hall, Eli Gilboa. Prorapeutic vaccination against shared antigens induced in future tumors [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B26.
Abstract B41: Bis-indole derived NR4A1 antagonist induces PD-L1 degradation and enhances antitumor immunity
Authors: Karki Keshav , Wright Gus , Un-Ho Jin , Mohankumar Kumaravel , Zhang Xing , Safe Stephen 
Published: March 2020

Abstract
PD-L1 is expressed in tumor cells and interaction with PD-1 in immune cells plays an important role in evading immune surveillance, and this can be overcome by immunotherapy using antibodies against PD-L1 or PD-1. This study reports a novel approach for targeting PD-L1. Results of RNA interference, chromatin immunoprecipitation, and mutational analysis show that in MDA-MB-231 and other human breast cancer cells and 4T1 mouse mammary tumor cells the PD-L1 expression is regulated by the nuclear receptor 4A1/NR4A1/Sp1 complex bound to the proximal GC-rich region of the PD-L1 gene promoter. Treatment breast cancer cells with bis-indole derived NR4A1 antagonists including 1,1-bis(3´-indolyl)-1-(3-chloro-4-hydroxy-5-methoxyphenyl)methane (ClOCH3) decreased expression of PD-L1 mRNA promoter-dependent luciferase activity and protein. In vivo studies using a syngeneic mouse model with Balb/c mice bearing orthotopically injected 4T1 cells showed that 2.5, 7.5, and 12.5 mg/kg/d of ClOCH3 decreased tumor growth and weight and inhibited lung metastasis. The NR4A1 antagonist ClOCH3 also decreased expression of CD+/CD4+/CD25+/FoxP3 regulatory T cells in tumor-infiltrating lymphocytes and increased Teff/Treg ratios. Thus, the potent anticancer activities of NR4A1 antagonists are also accompanied by enhanced antitumor immunity in breast cancer and represent a novel class of drugs that are immunotherapy mimics.
Note:This abstract was not presented at the conference.
Citation Format: Keshav Karki, Gus Wright, Jin Un-Ho, Kumaravel Mohankumar, Xing Zhang, Stephen Safe. Bis-indole derived NR4A1 antagonist induces PD-L1 degradation and enhances antitumor immunity [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B41.
Abstract B67: Development of MyD88 L265P mutation-specific TCR gene therapy for treatment of B-cell lymphoma and leukemia
Authors: Çinar Özcan , Busse Antonia , Pezzutto Antonio 
Published: March 2020

Abstract
Lymphoproliferative malignancies form a major group of cancers and are responsible for nearly 10% of all cancer deaths in developed countries. Adoptive transfer of engineered T cells has been shown to be a promising treatment approach; hence, screening and evaluation of cellular antigens for T-cell therapy with higher specificity and efficacy is a rapidly progressing area of research. Cancer-specific antigens derived by somatic mutations acquired during tumor development, so called “neoantigens,” represent a very advantageous target repertoire. Here we aimed to develop T-cell receptors (TCRs) targeting recurrent neoantigens in lymphoma and leukemia, for a truly cancer-specific immunotherapy. With this purpose, we have generated T-cell lines from multiple healthy donors targeting one of the most common driver mutations found in B-cell lymphomas: a missense mutation on adaptor protein MyD88 changing leucine at position 265 to proline (L265P). T cell lines generated by autologous in vitro priming were reactive selectively against the predicted mutant epitope restricted to HLA-B7, but not against the corresponding wild-type peptide. TCR alpha and beta nucleotide sequences from these T-cell lines were successfully cloned into a retroviral vector and expressed on T cells of healthy donors for further characterization. All cloned TCRs have shown mutation-specific and HLA-restricted reactivity with varying functional avidity. TCR-transduced T cells were able to selectively recognize and kill engineered target cells expressing MYD88 mutation, proving that the mutant epitope can be naturally processed by human proteasome and presented on HLA-B7. In order to further evaluate the therapeutic potency, we tested TCR-transduced T cells with non-Hodgkin lymphoma cell lines naturally harboring MyD88 L265P, and again observed HLA-restricted and mutation-specific reactivity and cytotoxicity, accompanied by antigen-induced proliferation. Taken together, our data suggest that mutation-specific TCRs can be used to target cancer cells with MyD88 L265P, and hold promise for immunotherapy of B-cell malignancies. Therefore, an application to the European Patent Office for variable region sequences of the TCRs has been made (EP19152801.7) in collaboration with Charité Technology Transfer Office. Preclinical safety screening of the TCRs and in vivo efficacy assessment in mice are in progress.
Citation Format: Özcan Çinar, Antonia Busse, Antonio Pezzutto. Development of MyD88 L265P mutation-specific TCR gene therapy for treatment of B-cell lymphoma and leukemia [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B67.
Abstract B69: Assessment of CCR5/maraviroc immunotherapy in combination with PD1 and MR-guided radiotherapy for treatment of pancreatic cancer
Authors: Hughes Sophie , Lanfredini Simone , Thappa Asmita , Mukherjee Somnath , O’Neill Eric 
Published: March 2020

Abstract
Background: Pancreatic ductal adenocarcinoma (PDAC) is the most prevalent form of pancreatic cancers with poor survival outcomes, due to late diagnosis, its propensity to metastasize, and lack of therapeutic efficacy under current chemotherapeutic regimens. Despite recent advancements in the field of immunotherapy, results from the clinic have demonstrated lack of efficacy when either radiotherapy (RT) or immunotherapy is used as a monotherapy in PDAC. However, recent publications revealed a synergistic effect on RT-induced immune modulation and reduced immune suppression when administered concurrently. Moreover, these reports demonstrate immune evasion in PDAC is dependent on the CCL5/CCR5 axis to recruit immunosuppressive T-regulatory cells (Tregs) into the tumor microenvironment. Therefore, targeting the migration of Tregs through modulation of CCL5/CCR5 can potentially inhibit tumor growth in pancreatic cancer.
Aim: This preclinical study evaluates the impact of fractionated MR-image guided radiotherapy (MR-IGRT) in combination CCR5 inhibitor and simultaneous inhibition of the immune checkpoint axis PD1/PD-L1 in PDAC.
Methods: For the purpose of this study we generated a syngeneic orthotopic pancreatic mouse model. Tumor cells derived from the Lox-Stop-Lox (LSL)-KrasG12D; LSL-Trp53R172H; Pdx1-cre (KPC) mouse model are injected in the tail of the pancreas. We are able to monitor tumor growth using a respiratory motion desensitized T2-weighted MRI imager, allowing the generation of high-resolution and high-contrast MRI data. Taking advantage of in-house developed technology, the MR-IGRT was delivered using the Small Animal Radiation Research Platform (SARRP) in combination with MRI imaging to deliver MR-guided fractionated radiotherapy. Concurrently with the radiotherapy, CCR5 inhibitor (maraviroc) and PD1 inhibitor were administrated at specific time points. To investigate the immunologic microenvironment, we developed a 17-color flow cytometry (FC) panel to immune-phenotype cytotoxic T, T regulatory, NK, NK/T and B cells, M-MDSC, PMN-MDSC, M1 and M2 macrophages in the peripheral blood and tumor infiltrate.
Results/Conclusions: Using the established orthotopic mouse model and immune monitoring, we are investigating the therapeutic benefit of immunomodulation of the CCL5/CCR5 axis in combination with PD1/PDL1 and radiotherapy.
Citation Format: Sophie Hughes, Simone Lanfredini, Asmita Thappa, Somnath Mukherjee, Eric O’Neill. Assessment of CCR5/maraviroc immunotherapy in combination with PD1 and MR-guided radiotherapy for treatment of pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B69.