bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract A060: Targeting glioma-macrophage interplay via LOX in PTEN-deficient glioblastoma
Authors: Chen Peiwen , Wang Alan , DePinho Ronald
Published: February 2019

Glioblastoma multiforme (GBM) is the most lethal form of brain cancer in adults. The median survival of GBM patients is only about one year after initial diagnosis. Genomic profiling has stratified GBM into various subgroups, which are driven by specific genetic alternations of core signaling pathways, including RTK/RAS/PI3K/PTEN, P53/ARF/MDM2 and RB/CDKN2A pathways. However, targeted therapies, such as therapy against EGFR, have failed in the clinic, and no effective therapeutic drugs are available to target tumor suppressors. A key reason for therapeutic failure is inter- and intra-tumoral cancer cell genetic instability and heterogeneity, resulting in aberrant activation of multiple signaling pathways within and across tumors. Stromal/immune cells in the tumor microenvironment (TME) are genetically stable, which not only play a pivotal role in GBM progression by affecting multiple cancer hallmarks, but can also be educated by cancer cells. However, whether and how the behavior and function of specific stromal/immune cells in the TME are regulated by cancer cell with specific genetic alterations in GBM remain relatively undefined. Utilizing a large scale of bioinformatic analysis in TCGA GBM patients, we revealed that genetic alteration (deletion/mutation) of PTEN in GBM patients specifically triggers immune response by promoting macrophage recruitment, without affecting macroglia and other immune cells. Using unbiased transcriptome profiling following functional validation, we identified that lysyl oxidase (LOX) is preferentially secreted by PTEN-deficient cancer cells. In vitro transwell migration assay and in vivo Matrigel Plug assay demonstrated that LOX is a potent macrophage chemoattractant. Transcriptome profiling following Gene Set Enrichment Analysis (GSEA) and functional validation demonstrated that activation of SRC and AKT signaling pathways drives LOX upregulation in PTEN-deficient cancer cells. Genetic and pharmacologic inhibition of LOX in PTEN-deficient cancer cells does not affect tumor cell proliferation in vitro, but markedly inhibits macrophage density and tumor growth in vivo. Using the bioinformatics analysis in clinical GBM samples, we demonstrated that LOX is enriched in GBM patients with higher macrophage density, and that these patients show lower survival. Together, our findings highlight the significance of PTEN-LOX axis in macrophage infiltration in GBM, and demonstrate a possibility of improving GBM treatment by targeting this axis-mediated macrophage recruitment.

Citation Format: Peiwen Chen, Alan Wang, Ronald DePinho. Targeting glioma-macrophage interplay via LOX in PTEN-deficient glioblastoma [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A060.
Abstract A078: Dissecting the myeloid lineage in human gliomas
Authors: Han Claudia Z. , Duttke Sascha H. , Ouyang Zhengyu , Preissl Sebastian , Schlachetzki Johannes C.M. , Nott Alexander , Fitzpatrick Conor , O'Connor Carolyn , Coufal Nicole G. , Gupta Mihir , Gonda David D. , Levy Michael L. , Sharona Ben-Haim , David Barba , Ciacci Joseph D. , Khalessi Alexander A. , Chen Clark C. , Ren Bing , Glass Christopher K.
Published: February 2019

The immune cell composition of the tumor microenvironment can be a decisive factor for tumor pathogenesis. Gliomas are tumors that develop from the glial cells of the brain and spinal cord and make up to 30% of all brain tumors. In gliomas, microglia and infiltrating macrophages can comprise up to 30 to 50% of total tumor-associated cells. Increased CD68 staining, a marker of microglia/macrophages, in adult gliomas is positively associated with histologic tumor grade. Despite the accumulated evidence substantiating a critical role for microglia and infiltrating macrophages in gliomagenesis, little is known is about the molecular mechanisms driving microglial contribution to tumor growth and whether microglia/macrophages are therapeutic targets in both low- and high-grade gliomas. Despite microglia sharing common properties with other tissue-resident macrophages, they express hundreds of genes at higher levels compared to other tissue-resident macrophages, many of which are influenced by the brain micro-environment. Additionally, engraftment of bone-marrow derived cells into the central nervous system fails to produce microglia identical to yolk sac-derived microglia at the transcriptional level. Hence, in any inflammatory context, including cancer, an interesting question arises: how does each population contribute to the pathogenesis and/or resolution of inflammation? To elucidate the role(s) of microglia/macrophages in gliomas, we isolated the myeloid fraction from primary pediatric and adult low-grade and high-grade gliomas using flow cytometry. By integrating bulk and single-cell transcriptome analysis, we find significant inter- and intratumoral heterogeneity within the myeloid population. Additionally, we find evidence for tumor environment-dependent gene change. In combination with ongoing comparative analysis of the corresponding epigenetic landscapes of the myeloid populations, we seek to decipher how the tumor microenvironment reprograms the transcription factor network in microglia/macrophages to generate tumor-promoting cells.

Citation Format: Claudia Z. Han, Sascha H. Duttke, Zhengyu Ouyang, Sebastian Preissl, Johannes C.M. Schlachetzki, Alexander Nott, Conor Fitzpatrick, Carolyn O'Connor, Nicole G. Coufal, Mihir Gupta, David D. Gonda, Michael L. Levy, Ben-Haim Sharona, Barba David, Joseph D. Ciacci, Alexander A. Khalessi, Clark C. Chen, Bing Ren, Christopher K. Glass. Dissecting the myeloid lineage in human gliomas [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A078.
Abstract A081: Tumors expressing ACKR1 exhibit a unique signature of tumor-infiltrating immune cells in women with breast cancer
Authors: Jenkins Brittany D. , Fleifel Talina , Martini Rachel , Ali Haythem , Newman Lisa , Davis Melissa
Published: February 2019

Tumor-associated immune cells, stroma and several other cell types make up the complex tumor microenvironment (TME) that contributes to a broad spectrum of potential clinical outcomes for breast cancer (BC) patients. Part of this delicate interplay is the interaction between pro-inflammatory chemokines and their receptors, which direct the migration of immune cells to areas of tumor-associated inflammation. Our focus in this complex process is on the role of the Atypical Chemokine Receptor 1 (ACKR1/DARC). In general immune response, its expression on erythrocytes helps to maintain chemokine homeostasis by sequestering chemokines in circulation while its expression on endothelial tissue transcytoses the chemokines from tissue into circulation, which ultimately affects which immune cells are brought to the TME. Its role in epithelial tissue expression is less understood. The purpose of this study is to investigate differential gene expression of ACKR1 in breast epithelial tumor tissue through IHC methods, and to determine how that expression correlates with both circulating and infiltrating proinflammatory chemokines. In addition, we will show this role to be associated with specific classes of tumor-infiltrating lymphocytes (TIL) in BC. Circulating chemokine levels for a variety of ACKR1-associated proinflammatory chemokines were determined using Luminex multiplexing assays. Results from our study cohort indicate differential expression of ACKR1 on epithelial tumor tissue, which correlated with a unique signature of immune cell infiltrates and associated proinflammatory chemokines. Tumors positive for AKCR1 expressed higher levels of circulating and infiltrating CCL2 (MCP-1) and lower levels of CXCL8 (IL-8). Tumor-expressing ACKR1 was also found to be associated with T-cells, B-cells, macrophages, and monocytes, where positive tumors tended to express a more robust profile of TILs. Our preliminary data suggest the presence or absence of ACKR1 on breast epithelial tumor tissue can influence the chemokine and immune cell profile within the TME, which can ultimately influence tumor aggressiveness, proliferation, and response to treatments, such as immunotherapies.

Citation Format: Brittany D. Jenkins, Talina Fleifel, Rachel Martini, Haythem Ali, Lisa Newman, Melissa Davis. Tumors expressing ACKR1 exhibit a unique signature of tumor-infiltrating immune cells in women with breast cancer [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A081.
Abstract A086: Omental fat in ovarian cancer induces lymphangiogenesis
Authors: Lenoir Bénédicte M.A. , Ferber Dyke , Starrach Victor , Suarez-Carmona Meggy , Schott Sarah , Zoernig Inka , Jäger Dirk , Halama Niels
Published: February 2019

Ovarian cancer metastasis occurs by direct multifocal seeding into the peritoneum as well as by migration through the lymphatic system. High-grade ovarian carcinoma patients often present with distant metastases. Significant risk factors for the development of those are stage, grade, and lymph node involvement. The increase of the number of lymphatic vessels seems to be implicated in ovarian tumor progression. While the tropism of ovarian cancer cells for fat is well described, the potential impact of an adipose-rich microenvironment on the dissemination of metastasis via lymphatic vessels has never been investigated. So far, in this study, we examined the effect of omental fat on lymphangiogenesis in ovarian carcinoma. For that we used a cohort of 80 ovarian cancer specimens. We observed a higher number of tumor-associated vessels and principally lymphatic vessels in ovarian cancer in contact with the omentum. These lymphatic vessels are predominantly localized along the fat tissue. A higher secretion of VEGF-C is observed in ovarian tissues containing fat compared to the ones without fat, giving a potential explanation to the observed increase of lymphatic vessels in fatty tissues. We also developed a healthy fat tissue explant culture model and treated whole tissue explants with ascites. Herein, we saw an increase of the number of adipose-derived stem cells (ADSCs). These ADSCs express lymphatic markers such as D2-40 and Lyve-1. We also observed an impact of fat supernatant on the proliferation, migration and tube formation of lymphatic endothelial cells in vitro. In conclusion, we can say that omental fat in ovarian cancer seems to have an impact on lymphangiogenesis. The close contact of ascites with fat tissue seems to lead to a differentiation of adipose-derived stem cells into lymphatic endothelial cells. Further investigations must be performed to understand the exact mechanisms underlying this phenomenon.

Citation Format: Bénédicte M.A. Lenoir, Dyke Ferber, Victor Starrach, Meggy Suarez-Carmona, Sarah Schott, Inka Zoernig, Dirk Jäger, Niels Halama. Omental fat in ovarian cancer induces lymphangiogenesis [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A086.
Abstract A100: ROBO2 is a stroma suppressor gene in the pancreas through regulation of TGF-β
Authors: Pinho Andreia V. , Bulck Mathias Van , Chantrill Lorraine , Arshi Mehreen , Herrmann David , Vennin Claire , Initiative APGI - Australian Pancreatic Cancer Genome , Gill Anthony , Timpson Paul , Biankin Andrew , Wu Jianmin , Rooman Ilse
Published: February 2019

Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis, being predicted to become the second leading cause of cancer-related death by 2030. Chronic pancreatitis is a risk factor for PDAC and both diseases are characterized by a strong desmoplastic response, comprised of activated myofibroblasts and immune cell infiltrates. Genomic aberrations in the SLIT-ROBO pathway are frequent in PDAC. Nevertheless, their role in the pancreas is unclear. We have used an integrative approach combining the study of murine models and PDAC patients with the objective of unraveling the function of the SLIT-ROBO signaling pathway in pancreatic disease. RNA expression of SLIT-ROBO genes was analyzed in murine normal pancreas, pancreatitis and PDAC. Primary cell cultures and experimental pancreatitis were studied using pancreas-specific Robo2 (Pdx1-Cre;Robo2F/F) and whole-body Slit1 (Slit1-/-) knockout mice. Gene and protein expression were assessed in a cohort of PDAC patients (n=109). In mouse pancreatitis and PDAC, epithelial Robo2 expression is lost while Robo1 expression becomes most prominent in the stroma. Pdx1Cre;Robo2F/F pancreatic cell cultures showed increased activation of Robo1-positive myofibroblasts and induction of TGF-β and Wnt pathways. Likewise, induction of pancreatitis in Pdx1Cre;Robo2F/F mice enhanced myofibroblast activation, collagen crosslinking, T-cell infiltration and tumorigenic immune markers. Similar results were obtained using Slit1-/- animals. Moreover, TGF-β inhibition using galunisertib treatment suppressed Robo2-mediated effects in the microenvironment. In patients, ROBO2 expression is overall low in PDAC, while ROBO1 is variably expressed in epithelium and high in the stroma. ROBO1 expression is correlated with markers of activated stroma, Wnt and TGF-β pathways. ROBO2low;ROBO1high subpopulation of patients present the poorest survival rates. In conclusion, Robo2 acts nonautonomously as a stroma suppressor gene by restraining myofibroblast activation and inflammation in the pancreatic microenvironment. ROBO1/2 expression is prognostic in PDAC patients and may guide therapy with TGF-β inhibitors or immunotherapies, currently being tested in clinical trials for advanced pancreatic cancer.

Citation Format: Andreia V. Pinho, Mathias Van Bulck, Lorraine Chantrill, Mehreen Arshi, David Herrmann, Claire Vennin, APGI - Australian Pancreatic Cancer Genome Initiative, Anthony Gill, Paul Timpson, Andrew Biankin, Jianmin Wu, Ilse Rooman. ROBO2 is a stroma suppressor gene in the pancreas through regulation of TGF-β [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A100.
Abstract A110: Efficacy of anti-PD1 immune checkpoint blockade involves the cooperative interaction of myeloid and lymphoid subpopulations in the tumor microenvironment
Authors: Schetters Sjoerd , Kooyk Yvette Van
Published: February 2019

Suppression of the immune system by solid malignancies has proven to be a driving force of tumor development and an effective target for therapeutic intervention. The suppression of cytolytic T-cells by inhibitory receptors like PD1 can be blocked by antagonistic antibodies, reinvigorating suppressed antitumor responses. Nonetheless, only a minority of patients show clinical benefit. It is becoming clear the efficacy of checkpoint blockade relies on many factors, including pretreatment conditions, collaboration between innate and adaptive immune cells and immune-architecture of the tumor microenvironment (TME). To investigate this, we studied the immune profiles of the PD1-unresponsive murine B16 melanoma and PD1-responsive MC38 colorectal carcinoma models, systemically and in the TME before and during treatment. By using high-dimensional flow cytometry and unsupervised clustering analyses based on immune checkpoints, we show comparable early establishment of heterogeneity of tumor-infiltrating CD8+ and CD4+ T-cells. However, PD1-responsive MC38 tumor shows correlations in abundance between specific CD8+ T-cell, NK cells and myeloid subsets before checkpoint blockade treatment, while the PD1-unresponsive B16 tumors do not show lymphoid-myeloid codependences. Interestingly, the abundance of monocyte-derived dendritic cells did not increase upon anti-PD1 treatment but instead showed abundance correlation with PD1 CD4+ and CD8+ T-cells, suggesting a putative interaction. The unresponsive B16 tumors showed increased correlation of cDC1 and cDC2 with Foxp3+ regulatory T-cells. We have visualized these putative interactions within the myeloid and lymphoid population in the changing immune-architecture of the TME, using multiplex fluorescence and confocal microscopy. We show heterogeneity and interactive hotspots during immune checkpoint blockade and postulate that successful anti-PD1 treatment requires the location-dependent cooperation of specific myeloid and lymphoid subsets in the TME.

Citation Format: Sjoerd Schetters, Yvette Van Kooyk. Efficacy of anti-PD1 immune checkpoint blockade involves the cooperative interaction of myeloid and lymphoid subpopulations in the tumor microenvironment [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A110.
Abstract A122: Self-recognition of Alu duplex RNAs is the basis for MDA5-mediated interferonopathies
Authors: Ahmad Sadeem , Mu Xin , Hur Sun
Published: February 2019

Melanoma Differentiation Associated Gene-5 (MDA5) is an innate immune receptor that binds to viral double-stranded RNAs (dsRNAs) and initiates type I and III interferon signaling cascade thereby playing a key role in antiviral immune response. Recently, a number of mutations that lead to aberrant activation of MDA5 have been implicated in various autoinflammatory disorders including Aicardi-Goutières syndrome. The mechanistic basis of this constitutive MDA5 activation, however, has remained elusive. An understanding of the subtle balance of self vs. non-self discrimination by MDA5 is important, especially in the context of recent reports demonstrating the targeted activation of MDA5 as a potential therapeutic strategy against diverse carcinoma. Our work revealed a hitherto unknown role played by the RNA-rich cellular environment in preventing aberrant MDA5 activation by imposing cooperative filament assembly on dsRNAs as a functional requirement for signal activation. We further employed a novel RNase protection-RNAseq approach to show that the disease-causing gain-of-function (GOF) mutants of MDA5 can form signaling-competent filaments on endogenous RNA populations comprising mainly Alu RNA duplexes. Strikingly, under physiologic conditions, the wild type MDA5 is not activated by Alu RNAs because of its sensitivity to structural irregularities such as bulges and mismatches commonly occurring in Alu:Alu hybrids. The GOF mutants, on the other hand, show reduced sensitivity to disruptions in duplex RNA structures as revealed by our in-depth biochemical probing. Overall, the work reveals the underlying mechanism behind MDA5-mediated inflammatory disorders. Moreover, it highlights the unique role played by Alu RNAs as an evolutionary tether on MDA5, keeping its affinity towards “self” ligands under check during the course of evolution.

Citation Format: Sadeem Ahmad, Xin Mu, Sun Hur. Self-recognition of Alu duplex RNAs is the basis for MDA5-mediated interferonopathies [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A122.
Abstract A123: Skewed CD4 and CD8 T-cell differentiation in pancreatic cancer patients
Authors: Alanio Cecile , Bengsch Bertram , Gies Josephine R. , Henrickson Sarah , Weng Nan Ping , Ritz-Romeo Janáe A , O'Hara Mark , Melenhorst Joseph J , Lacey Simon , Young Regina M , June Carl H , Wherry E. John
Published: February 2019

To understand potential immune system alterations in newly diagnosed, untreated, pancreatic cancer patients and provide a foundation for immunotherapy, we profiled PBMC from pancreatic ductal adenocarcinoma (PDA) patients and age-matched healthy controls using high-dimensional CyTOF analysis. We developed two immune profiling panels: a broad profiling panel that includes 45 phenotypic markers that together permit the identification and enumeration of the main innate and adaptive immune cell subsets in humans, and a deep profiling panel that includes 45 features focusing on T-cell phenotype and biology. We report a 2-fold increase in monocytes, more regulatory T-cells, and more plasmocytes in circulation in pancreatic cancer patients as compared to age-matched controls, as well as a bias towards cytokine-producing NK cells. Using high-dimensional approaches, we observed skewed T-cell differentiation in pancreatic cancer patients, with peripheral blood CD8 T-cells being biased towards more CD45RA-positive CD27-positive CCR7-positive CD95-positive CD49d-positive stem cell memory cells (P=7x10-5), more CD45RA-negative CD27-positive CCR7-negative effector memory cells (P=0.002) and less CD45RA-positive CD27-negative CCR7-negative late effector memory cells (P=0.003) as compared to age-matched controls. Strikingly, when examinating T-cell differentiation in human spleens, we found increased proportions of late effector memory T-cells in the splenic CD8 T-cell compartment of pancreatic cancer patients as compared to age-matched controls. These results suggest an impaired T-cell trafficking in pancreatic cancer patients, with late memory T-cells being retained in the spleen. We are now investigating the mechanisms underlying these observations, as well as their impact on T-cell immunity of the cancer patients. Our goal is to understand the nature of the skewing and how any changes in baseline immune health of the T-cell compartment relate to disease progression and/or response to therapy. These studies should provide a foundation for improving therapy in pancreatic cancer patients.

Citation Format: Cecile Alanio, Bertram Bengsch, Josephine R. Gies, Sarah Henrickson, Nan Ping Weng, Janáe A Ritz-Romeo, Mark O'Hara, Joseph J Melenhorst, Simon Lacey, Regina M Young, Carl H June, E. John Wherry. Skewed CD4 and CD8 T-cell differentiation in pancreatic cancer patients [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A123.
Abstract A128: Tumor endothelial cells say IDO to CD40-stimulating immunotherapy
Authors: Dimberg Anna , Karampatzakis Alexandros , Tuit Sander , Ramachandran Mohanraj , Fotaki Grammatiki , Hooren Luuk van , Huang Hua , Lugano Roberta , Aura Kaunisto , Ellmark Peter , Mangsbo Sara M , Schultze Joachim L. , Essand Magnus , Georganaki Maria
Published: February 2019

CD40, a tumor necrosis factor receptor superfamily member, is a promising immune-boosting target in cancer immunotherapy due to its role in promoting antitumor responses of immune cells. CD40 is also expressed on endothelial cells but the response of the tumor-associated vasculature to CD40-stimulating immunotherapy has not been studied. Herein, we have performed RNA-sequencing analysis of murine tumor endothelial cells (TECs) isolated from B16.F10 melanoma and MB49 bladder cancer treated with agonistic CD40 monoclonal antibody (mAb) or isotype control. Gene set and gene ontology enrichment analyses of the differentially expressed genes revealed that CD40 mAb treatment induces interferon-γ (IFNγ) signaling in the tumor microenvironment associated with up-regulation of immunosuppressive genes in TECs, including the enzyme indoleamine 2, 3-dioxygenase 1 (IDO1). Importantly, IDO1 was preferentially expressed in endothelial cells in the tumor and was positively correlated to infiltration of T-cells in the tumor microenvironment. In vitro, endothelial cells up-regulated IDO1 in response to T-cell-derived IFNγ, but not in response to CD40-stimulation. Collectively, our data suggest that IDO1 up-regulation in TECs occurs as a response to T-cell activation. Combining CD40 mAb therapy with the IDO1 inhibitor epacadostat delayed tumor growth and increased survival of B16.F10 tumor-bearing mice, which was associated with increased activation of cytotoxic T-cells. Hereby, we have uncovered a novel immunosuppressive feedback mechanism, in which the tumor vasculature limits the response to cancer immunotherapy by up-regulating IDO1.

Citation Format: Anna Dimberg, Alexandros Karampatzakis, Sander Tuit, Mohanraj Ramachandran, Grammatiki Fotaki, Luuk van Hooren, Hua Huang, Roberta Lugano, Kaunisto Aura, Peter Ellmark, Sara M Mangsbo, Joachim L. Schultze, Magnus Essand, Maria Georganaki. Tumor endothelial cells say IDO to CD40-stimulating immunotherapy [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A128.
Abstract A148: A hydrogel platform for the delivery of specialized pro-resolving mediators to treat chronic inflammatory disease
Authors: Pillai Padmini Sushila , Webster Jamie , Langer Robert
Published: February 2019

The resolution of acute inflammation is an active process orchestrated by mediators that prevent further recruitment of inflammatory cells and promote clearance of microbes and dying cells. Chronic inflammation can arise when resolution is diminished due to a scarcity of these pro-resolving mediators. Current immunosuppressive drugs for the treatment of chronic inflammatory diseases such as IBD, arthritis, or psoriasis temporarily block inflammation without initiating resolution or tissue repair, leading to the recurrence of chronic inflammation. Additionally, systemic administration of these drugs leaves patients susceptible to tuberculosis, lymphoma, and opportunistic infections. Resolvins are a class of evolutionarily conserved lipid mediators that return tissue to homeostasis without immunosuppression by promoting phagocytosis of debris and microbes, and preventing proinflammatory cytokine production and cellular infiltration. To enhance dose sparing and stability, we have developed a tunable hydrogel platform to deliver resolvins to various sites of chronic inflammation. For oral delivery, this hydrogel is further encapsulated into a pH-sensitive microparticle formulated using anionic polymers, to target the large intestine. Using a mouse model of colitis, we demonstrate the ability of the hydrogel to resolve intestinal inflammation, initiate repair of the intestinal barrier, and regulate the gut microbiota. Our tunable hydrogel platform could have profound effects on the prevention of gastrointestinal cancers and chronic inflammatory disease.

Citation Format: Padmini Sushila Pillai, Jamie Webster, Robert Langer. A hydrogel platform for the delivery of specialized pro-resolving mediators to treat chronic inflammatory disease [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A148.
Abstract A152: Investigating metabolic basis of neurotoxicity during CAR-T therapies
Authors: Salloum Darin , Santomasso Bianca , Brentjens Renier J. , Wendel Hans-Guido
Published: February 2019

Chimeric antigen receptor T (CAR-T) cell therapies are rapidly becoming first in line therapies for treatment of hematologic malignancies. This is due to the efficacy of the treatment and long-lasting tumor responses. However, CAR-T therapies are associated with unique set of acute toxicities— cytokine release syndrome (CRS) and neurologic toxicities—the cause of which is not clear. As other immune therapies are becoming more widely used, these toxicities are observed in patients undergoing bispecific T-cell engaging antibodies (BiTEs) and checkpoint blockade therapies. Here, we sought to define metabolic changes in patients undergoing chimeric antigen receptor (CAR) T-cell therapy for B-acute lymphoblastic leukemia. We performed metabolic analysis of amino acids in serum samples, and identified significant up-regulation of tryptophan-kynurenine metabolism in patients with high-grade neurotoxicity. In-depth look at tryptophan-kynurenine pathway in cerebrospinal fluid patient samples determined quinolinic acid up-regulation to correlate with low- and high-grade neurotoxicity, indicating local production of this metabolite. We show that quinolinic acid is produced by activated monocytes and microglia in response to Il1beta and TNF. Importantly, tryptophan metabolite—kynurenine— stimulates Il1beta production and further activation of monocytes, possibly exacerbating CSR and neurotoxicity. This study suggests that inhibition of tryptophan-kynurenine pathway may offer some benefit to manage neurotoxicity and CRS associated with CAR-T-cell therapy treatment.

Citation Format: Darin Salloum, Bianca Santomasso, Renier J. Brentjens, Hans-Guido Wendel. Investigating metabolic basis of neurotoxicity during CAR-T therapies [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A152.
Abstract A169: Macrophage targeted zoledronic acid conjugated biomineral nanoparticles for γδT-cell-based cancer immunotherapy
Authors: Ashokan Anusha , Anoop Minu , Surendran Siju , Balakrishnan Aparna , Anna Ida M. , Ramkumar Anjana , Madathil Girish Chundayil , Harish Vijay , Koyakutty Manzoor
Published: February 2019

Nanoparticle platforms can be engineered to deliver immune-stimulatory molecules to specific immune cell populations, thereby evoke desired response. Here, we present a novel biomineral nanoparticle system for macrophage specific delivery of bisphosphonate molecules to evoke activation of γδ T-cells for cancer immunotherapy. Generally, γδ T-cells therapy is implemented either by ex vivo expansion followed by adoptive transfer or by in vivo activation using intravenous injection of bisphosphonates. One of the major limitations of intravenously injection of bisphosphonates such as zoledronic acid is its unfavorable biodistribution in the skeletal system due to covalent binding with calcium in the bone. In the present work, we have pre-conjugated zoledronic acid in a calcium-containing biomineral nanoparticle (Zol-BM) that has spontaneous specificity towards macrophages in the liver, spleen and lymph nodes. This enabled targeted expression of γδT-cell stimulating ligand, isopentyl pyrophosphate, in macrophages, leading to enhanced activation of γδT-cells. Optimized Zol-BM showed a drug conjugation efficiency of ~95% with particle size ~ 100 nm and zeta potential, -15mV. The compatibility of Zol-BM was tested in primary human peripheral blood mononuclear cells and macrophages cell lines. The biodistribution analysis of Zol-BM in healthy rat models showed accumulation in liver, spleen and lymph nodes which was confirmed by MRI and Prussian-blue analysis. Flow cytometry based γδT-cell proliferation analysis gave ~18% enhancement in γδ T-cell subset compared to untreated control. Thus, we show that by rational design of engineered nanoparticles, specific immuno-stimulatory molecules like zolendronate can be delivered to desired immune cells of interest (macrophages) for activating another sub-population of immune cells such as γδ T-cells, for cancer-immunotherapy applications.

Citation Format: Anusha Ashokan, Minu Anoop, Siju Surendran, Aparna Balakrishnan, Ida M. Anna, Anjana Ramkumar, Girish Chundayil Madathil, Vijay Harish, Manzoor Koyakutty. Macrophage targeted zoledronic acid conjugated biomineral nanoparticles for γδT-cell-based cancer immunotherapy [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A169.
Abstract A172: Cxcr6-deficiency impairs cancer vaccine efficacy and resident memory CD8+ T-cells recruitment in tumor
Authors: Karaki Soumaya , Blanc Charlotte , Tran Thi , Galy-Fauroux Isabelle , Anson Marie , Golub Rachel , Tartour Eric
Published: February 2019

Immunization route is directly correlated with cancer vaccine efficacy. Our team previously showed that mucosal (intranasal, i.n.) and systemic (intramuscular) vaccinations are both able to induce systemic specific CD8+ T-cells but only i.n. immunization allows an efficient control of mucosal tumor growth. Indeed, the i.n. vaccination favors the tumor infiltration of specific CD8+ T-cells and especially tissue-resident memory T-cells (Trm), which are crucial for a potent antitumor activity. Based on a transcriptomic analysis, we have identified a chemokine receptor, CXCR6, highly expressed by these specific Trm CD8+ T-cells, induced by the i.n. vaccination. To understand the role of CXCR6 in vaccination efficacy, we have set up a body of experiments using heterozygous Cxcr6gfp/+ mice, where GFP reflects CXCR6 expression and homozygous Cxcr6-deficient mice Cxcr6gfp/gfp.We have then confirmed CXCR6 expression on specific Trm CD8+ T-cells induced by i.n. vaccination in lung mucosa. Using an orthotopic head and neck tumor model, CXCR6 expression on tumor-infiltrating Trm induced by i.n. immunization has also been reported. In addition, we showed that Cxcr6-deficiency impairs mice survival in a prophylactic and therapeutic i.n. vaccination settings in various mucosal tumor models. In this Cxcr6-deficient mouse model, the loss of vaccine-induced protection against tumor graft correlates with a clear reduction of Trm infiltration in tumor. Finally, in a cohort of human lung cancer, we have observed endogenous CXCR6+ Trm infiltrating these tumors in situ. To conclude, we have identified CXCR6 as a required parameter to recruit the crucial anti-tumor Trm in mucosal tumor. Our results finally indicate that CXCR6 might be a new surrogate biomarker to evaluate antitumor vaccine efficacy.

Citation Format: Soumaya Karaki, Charlotte Blanc, Thi Tran, Isabelle Galy-Fauroux, Marie Anson, Rachel Golub, Eric Tartour. Cxcr6-deficiency impairs cancer vaccine efficacy and resident memory CD8+ T-cells recruitment in tumor [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A172.
Abstract A180: HHLA2 is a novel tumor-expressed member of the B7 immune checkpoint family
Authors: Chinai Jordan Manek , Wang Hao , Tang Xudong , Janakiram Murali , Cheng Haiying , Zang Xingxing
Published: February 2019

The purpose of this study was to assess the function and expression-regulation of the new B7 family member, HHLA2, in the tumor microenvironment. HHLA2 is a newly identified B7 family member that has been reported to both inhibit and stimulate T-cell function in vitro. Expression of HHLA2 has been noted on a wide variety of cancers and relatively few normal tissues. The function of HHLA2 in the tumor microenvironment remains elusive and the mechanisms regulating its expression are currently unknown. Challenges to addressing these questions include the lack of a functional HHLA2 gene in mice and, consequently, the lack of in vivo tumor models in which HHLA2 can be studied. Here we assess factors that drive expression of HHLA2 in vivo and present the first humanized mouse model to study the function of HHLA2 expression in the tumor microenvironment. Human cancer cell lines derived from lung, prostate, pancreas, kidney, and colon malignancies were identified with varying levels of HHLA2 expression. HHLA2 surface expression was monitored as these cell lines were grown in vivo as tumors in NSG mice and in vitro under conditions including cytokine stimulation, 3D culture, and hypoxia. Expression was assessed by both flow cytometry and qPCR. HHLA2-knockout cancer cell lines and controls were generated using CRISPR and grown as tumors in NSG mice with human immune cells. These tumors were dissociated and the immune infiltrates were phenotyped by flow cytometry. HHLA2 was upregulated in numerous human cancer cell lines in vivo and expression was reduced or lost in vitro under standard cell culture conditions. Conditions mimicking the tumor microenvironment including 3D culture, hypoxia, and cytokine stimulation all contributed to HHLA2 upregulation. We successfully generated HHLA2-knockout human cancer cell lines and developed a humanized tumor immunotherapy model. HHLA2-expressing tumors contained significantly less infiltrating CD8 and CD4 T-cells than the HHLA2-knockout tumors. The T-cells were also phenotypically less active in the HHLA2-expressing tumors. Expression of HHLA2 in human cancers is driven by environmental conditions that are specific to the tumor microenvironment and this expression appears to have a suppressive effect on infiltrating T-cells. HHLA2 is the newest B7 family member and a promising candidate for targeted immunotherapy against a wide range of cancers.

Citation Format: Jordan Manek Chinai, Hao Wang, Xudong Tang, Murali Janakiram, Haiying Cheng, Xingxing Zang. HHLA2 is a novel tumor-expressed member of the B7 immune checkpoint family [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A180.
Abstract A181: Origin of tumor-elicited cytotoxic innate-like T-cell responses
Authors: Chou Chun , Dadi Saida , Nixon Briana G. , Li Ming
Published: February 2019

In most murine cancer models and human patients, cell-mediated cytotoxicity is critical for the destruction of tumor cells. Conventional CD8+ T-cells, which possess cytotoxic capacity, are thus the targets of most cancer immunotherapies. However, tumors that are poorly antigenic, immunosuppressive, or have low T-cell infiltration are often resistant to CD8+ T-cell-centric modalities. Thus, exploring the roles of other cytotoxic immune cell types will complement and synergistically enhance the potency of current treatments. Recently, our lab identified a population of tumor-infiltrating innate-like T-cells (ILTCs), which constitutively express high levels of cytotoxic molecules, are closely juxtaposed to tumor cells, and readily induce cytolysis of transformed target cells. Although armed with a polyclonal T-cell receptor (TCR) repertoire similar to conventional T-cells, ILTCs are phenotypically unconventional and innate-like by the concomitant expression of activating and inhibitory receptors typically found on natural killer (NK) cells but not on conventional T-cells. The specificity of ILTC TCR is unknown, and the extent to which TCR engagement maintains ILTCs and activates their effector functions in the context of tumor also remains ill-defined. While ILTCs and conventional T-cells share a thymic origin, genome-wide analyses revealed a distinct epigenetic landscape in ILTCs compared to conventional T-cells, suggesting that ILTCs constitute a disparate lineage and that alternative selection processes drive their fate choice during thymic development. Here, we showed that commitment to ILTC fate is instructed by distinct TCR specificity. Utilizing TCR retrogenic models and adoptive cell transfer approach, we identified the thymic and circulating ILTC-lineage-committed progenitor. These precursors are continuously generated by adult hematopoiesis and replenish the ILTC pool as the tumor develops. By acutely ablating TCRs, we demonstrated that tumor-resident ILTCs continuously require TCR for their maintenance. Together, our results delineate the ontogeny of ILTCs. Their unique TCR specificity, homing pattern, and innate-like features make ILTC a powerful candidate for bioengineering and adoptive cellular therapy.

Citation Format: Chun Chou, Saida Dadi, Briana G. Nixon, Ming Li. Origin of tumor-elicited cytotoxic innate-like T-cell responses [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A181.
Abstract A185: Effective expansion of poly-functional tumor-reactive TILs from NSCLC correlates with an immune-engaged T-cell profile in tumor tissues
Authors: Groot Rosa De , Loenen Marleen M. van , Guislain Aurélie , Amsen Derk , Haanen John B.A.G. , Monkhorst Kim , Hartemink Koen J. , Wolkers Monika C.
Published: February 2019

Non-small cell lung cancer (NSCLC) is the second most frequently occurring type of cancer. Because of the high mortality rates with the current treatment regimens, novel therapeutic approaches are warranted. The high mutational rate of the tumors, and the high level of T-cell infiltrates should render NSCLC patients eligible for autologous T-cell therapy. Here we show that tumor-infiltrating lymphocytes (TILs) from treatment naive, stage I-IIIa NSCLC tumors can be effectively expanded and reprogrammed. With an optimized detection essay for tumor-reactive T-cells, we observed that 13/17 tested TIL products (76.5%) from primary NSCLC tumor tissues contained cytokine-producing CD4+ and/or CD8+ T-cells in response to primary tumor digest. Tumor responses ranged from 0.5%-30%, and correlated well with activation markers on CD4+ and CD8+ T-cells. Importantly, 29.4% of the TIL products contained poly-functional T-cells that produced TNF-alfa and/or IL-2 in addition to IFN-gamma, and poly-functional T-cells correlated with high levels of tumor reactivity. Furthermore, high percentages of CD103+CD69+CD8+ T-cells, PD-1+CD4+ T-cells and FoxP3+CD25+CD4+ T-cells in the tumors were good predictors for the generation of highly tumor-reactive TIL products. In conclusion, we show that most NSCLCs contain tumor-specific T-cells that can be efficiently expanded and become highly poly-functional, depending on the initial T-cell profile of TILs. Our findings show the feasibility of culturing tumor-reactive TILs from NSCLC and provide keys to individualize adoptive T-cell therapy. Therefore, autologous T-cell therapy should be reconsidered as treatment for NSCLC patients.

Citation Format: Rosa De Groot, Marleen M. van Loenen, Aurélie Guislain, Derk Amsen, John B.A.G. Haanen, Kim Monkhorst, Koen J. Hartemink, Monika C. Wolkers. Effective expansion of poly-functional tumor-reactive TILs from NSCLC correlates with an immune-engaged T-cell profile in tumor tissues [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A185.
Abstract A192: Non-IL-2 blocking anti-CD25-targeting antibodies: depletion of regulatory T-cells driving optimal effector response for rejection of established tumors
Authors: Goubier Anne , Solomon Isabelle , Vargas Frederick Arce , Zervas Dimitrios , Qing Chen , Salimu Josephine , Brown Mark , Merchiers Pascal , Peggs Karl S. , Quezada Sergio A.
Published: February 2019

The accumulation of regulatory T-cells (Tregs) in the tumor hampers effector antitumor activity and correlates with a poor prognosis in several human cancers. Increasing the effector T-cell (Teff) to regulatory T-cell (Treg) ratio is known to result in improved control of established tumors. Studies demonstrating high levels of CD25 expression on Tregs and only low levels on Teff in human tumors have underscored its relevance as a target for Treg depletion. This supported the development of anti-CD25 depleting monoclonal antibodies (mAbs) as a promising monotherapy as well as combination partner in cancer immunotherapies. To date, anti-CD25 antibodies for clinical use have been designed to block IL-2 binding and signaling through the IL-2 receptor complex and also depletes CD25 positive cells. Since IL-2 is a critical cytokine involved in T-cell activation and proliferation, we hypothesized that a depleting antibody targeting CD25 but unable to block IL-2 signaling would promote a more potent anti-tumor response by preferentially depleting Tregs while still allowing IL-2 to stimulate effector T-cells expressing low levels of CD25 on their surface. We therefore compared the functional activity of anti-mouse CD25 depleting mAbs with and without IL-2 blocking activity. After having confirmed their differential impact on IL-2 signaling in vitro and in vivo, we evaluated the therapeutic activity of these mAbs in various syngeneic tumor models. While both the IL-2 blocking and non-IL-2 blocking mAbs showed equivalent Treg-depleting activity, the antibody sparing IL-2 signaling (αCD25NIB) promoted stronger antitumor effect than the IL-2 blocking mAb, with complete tumor regression observed in 70-100% of the mice after a single administration of the antibody. We demonstrated that the αCD25NIB would be an ideal partner for combination against several tumor types including “immune cold” tumors and αPD-L1 resistant tumors. Our data demonstrate that targeting CD25 with ADCC enabled antibodies preserving IL-2 signaling is a novel and powerful strategy for rejection of established tumors via depletion of Treg cells and enhanced, cell intrinsic, IL-2-driven effector T-cell activation.

Citation Format: Anne Goubier, Isabelle Solomon, Frederick Arce Vargas, Dimitrios Zervas, Chen Qing, Josephine Salimu, Mark Brown, Pascal Merchiers, Karl S. Peggs, Sergio A. Quezada. Non-IL-2 blocking anti-CD25-targeting antibodies: depletion of regulatory T-cells driving optimal effector response for rejection of established tumors [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A192.