bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stellate cells as mediators of immune suppressive features in pancreatic cancer
Authors: McQuinn Christopher William , Mace Thomas A , Farren Matthew R , Komar Hannah , Kitano Mio , Yu Lianbo , Bloomston Mark , Zhong Xiaoling , Zimmers Teresa , Bekaii-Saab Tanios , Lesinski Gregory Brian 
Published: January 2023

Abstract
One hallmark of pancreatic ductal adenocarcinoma (PDAC) is the dense stroma that includes activated myofibroblast-like cells termed ‘pancreatic stellate cells’ (PSC). We hypothesized that antitumor immunity is restrained by PSC, and that key pathways can be identified to augment efficacy of immunotherapy. To gain insight into the most relevant soluble factors and pathways, primary PSC (n=10) were isolated from PDAC patients. A normal human pancreatic fibroblast (HPF) cell line was used as a control. RNA obtained from PSC or HPF underwent nanostring analysis using the nCounter PanCancer Immune Profiling panel. Cytokine and chemokine expression in supernatants was measured via bioplex analysis or ELISA. Unsupervised clustering analysis revealed the greatest fold change in IL-6 transcript between PSC and HPF, versus other cytokines in the panel. Abundant IL-6 expression was validated in supernatants by bioplex analysis, and was accompanied by other cytokines, most notably, MCP-1, VEGF and SDF-1. Supernatants from human PSC also expanded suppressive myeloid cells from bulk, human peripheral blood mononuclear cells. Analysis of a separate cohort of human pancreatic tumors (n=12) via immunohistochemistry further revealed abundant IL-6 protein in stromal regions of tumors. This prominent stromal localization of IL-6, and STAT3 phosphorylation STAT3 was also evident in pancreata from mice with mutant Kras-driven, PDAC. These data point to stromal IL-6 as a target in PDAC, and complement our data confirming plasma IL‑6 as a poor prognostic factor in a large cohort (n=73) of treatment naïve PDAC patients. Ongoing studies are exploring the role of IL-6 in PSC and the effect of targeting this cytokine in combination with immunotherapy.
CD8α+ Dendritic Cells Induce Leukemia-Specific T cell Tolerance
Authors: Kline Douglas E , Chen Xiufen , Fosco Dominick , Kline Justin 
Published: January 2023

Abstract
Antigen presenting cells (APCs) are critical for the acquisition of tumor-derived antigens and the orchestration of anti-tumor T cell responses. Batf3-dependent CD8α+ and CD103+ dendritic cells (DCs) have been implicated as the critical APCs that initiate and maintain spontaneous CD8+ T cell priming against solid tumors. In contrast, little is known about the APCs that regulate immunity against malignancies of hematopoietic origin. Using a murine model of acute myeloid leukemia (AML) that induces T cell tolerance, we demonstrate that leukemia-derived antigens are exclusively acquired and cross-presented by CD8α+ DCs. In the steady state, CD8α+ DCs rapidly induce leukemia-specific T cell tolerance, which can be prevented upon the activation of these DCs. Together, our data reveal that the same DC lineage can imprint disparate T cell fates in mice with solid verses hematopoietic malignancies. In the context of solid tumors, Batf3-dependent DCs stimulate productive effector responses; however, in AML-bearing mice, CD8α+ DCs actively promote T cell tolerance.
B cell subset biology in a tumor microenvironment model
Authors: Riggs James Edward , Goldman Naomi , Valiuskyte Kornelija , DePierri Kelley , Somerville John 
Published: January 2023

Abstract
The high myeloid to lymphoid ratio of cultured peritoneal cavity (PerC) leukocytes can serve as an in vitro model to study the tumor microenvironment (TME). C57BL/6J PerC T cell responses to TCR ligation (anti-CD3) and mitogen (ConA) are suppressed in these cultures. Likewise, the PerC B cell response to BCR (F[ab’2] anti-IgM) and TLR4 (TLR4L/LPS) ligation are suppressed. T cell suppression can be liberated by neutralizing IFNγ or by blocking iNOS with 1-methyl arginine. The BCR response is recovered by blocking prostaglandin production with indomethacin; the LPS response by neutralizing IL10. To dissect putative receptor-ligand signals in this model, we investigated expression of the inhibitory cell surface marker PDL1/B7H1/CD274 on PerC cells. TCR ligation increased PDL1 expression on macrophages (Mfs), B1, and B2 cells and was reduced by blocking IFNγ. TLR4 ligation increased PDL1 expression on Mfs and both B cell subsets and was reduced by blocking IFNAR1. Interestingly, BCR ligation increased B7H1 and Class II expression on Mfs and B2 cells, but not B-1 cells. Increased B7H1 expression could be reduced by neutralizing IL6, IFNβ, IFNγ, or IFNAR1. TCR ligation led to B1, but not B2, cell division and proliferating B cells increased IL10 production. These findings illustrate that TCR, and surprisingly BCR, ligation can foster immune suppression in macrophage-dense cultures and suggest that regulatory B cells must be considered when designing immunomodulatory cancer therapies.
PRMT5 is a novel cofactor of Foxp3 and can be a target for tumor immunotherapy
Authors: Nagai Yasuhiro , Ji Mei , Xiao Yan , Zhang Hongtao , Li Bin , Ohtani Takuya , Greene Mark I 
Published: January 2023

Abstract
Regulatory T cells (Tregs) are a subpopulation of T cells specialized for suppressing host immune systems, whose dysfunction can lead to severe autoimmunity and inflammatory disease in humans and animals. In a tumor bearing host, an enhanced activity of Tregs may limit host immunity against tumor antigens. Our laboratory has studied the Foxp3 transcriptional complex at the molecular and atomic levels. We identified a protein arginine methyl transferase 5 (PRMT5) as a binding partner of Foxp3. Mice whose expression of PRMT5 was deleted in Tregs developed severe autoimmunity, scurfy like phenotypes and died at ~3 weeks of age. A limited number of Tregs were found in the spleen, but there were normal numbers of Tregs in the peripheral lymph nodes. Tregs that lacked PRMT5 displayed limited suppressive function when compared to wild type cells. Two types of PRMT5 inhibitors, EPZ004777 and EPZ015666, were studied to determine if inhibition of PRMT5 reduces human Treg functions. While EPZ004777 could inhibit human Treg functions in vitro, EPZ015666 had limited ability to limit these Treg activities. EPZ004777 could also inhibit the methylation of Foxp3. Injection of EPZ004777 to p185/erbB2/neu tumor bearing mice enhanced the effect of anti-erbB2/neu monoclonal antibody therapy. Furthermore, treatment with EPZ004777 reduced the numbers of tumor infiltrating Tregs, indicating that EPZ004777 functions by inhibiting Treg functions and/or migration of Tregs into p185 expressing tumors. These studies support the concept that controlling PRMT5 activity is a promising strategy in a p185 targeted monoclonal antibody therapy in which host immunity against tumors is augmented in a Foxp3 dependent manner.
Growth inhibitory effects of Withaferin A on MDS-L cells – A human 5q Myelodysplastic Syndrome (MDS) cell line
Authors: Oben Karine Zinkeng , Gachuki Beth , Akunuru Shailaja , Jinpeng Liu , Brandon Jason , St Clair Daret , Wang Chi , Geiger Hartmut , Gupta Ramesh , Bondada Subbarao 
Published: January 2023

Abstract
Myelodysplastic syndrome (MDS) affects bone marrow production of white blood cells and erythrocytes. At least 40% of MDS patients who go into remission after treatment eventually progress to acute myelogenous leukemia (AML) which is very difficult to treat. Hence, there is a compelling need for new and better therapies. Withaferin A (WFA), a withanolide isolated from Winter cherry (Withania somnifera), has been shown to have potent anti-cancer properties in several animal models of cancer. We found that WFA inhibited the growth of MDS-L cells, a human cell line derived from a 5q MDS patient. Treatment with WFA induced apoptosis of MDS-L cells, indicated by the cleavage of caspase-3 as early as 6hrs after treatment and a dose dependent increase of annexin positive cells. Cell cycle analysis revealed that WFA caused MDS-L cells to arrest at S and G2/M and accordingly there was a reduction in cyclin A/CDK2 and cyclin B/CDK1 respectively. WFA also inhibited the activity of the heat shock protein (Hsp 90) chaperone as shown by the degradation of its client proteins such as Akt, an important pro-survival kinase and increased expression of Hsp70 which partially compensates for decrease in Hsp90 function. Interestingly, the mechanism by which WFA acts on MDS-L cells is independent of its well-recognized action on Nf-κB. Microarray analysis of gene expression in MDS-L cells showed a dramatic increase in several genes that may have a role in Nf-κB independent growth inhibitory effects of WFA. Studies with a xenograft model of MDS-L cells in NSGS mice suggest WFA might also be effective in vivo. The potent anti-proliferative and anti-survival effects of WFA on MDS-L cells, suggest that it could be a novel therapeutic agent for the treatment of 5q MDS.
Aberrant tumor derived LPA production suppresses CD8+ T cells though the LPA5R to promote tumor growth.
Authors: Mathew Divij , Strauch Pamela , Berry Karin Zemski , Schroeder Kristin Shotts , Murphy Robert , Torres Raul M 
Published: January 2023

Abstract
As a bioactive signaling lipid, lysophosphatidic acid (LPA) is in the same phospholipid family as sphingosine-1-phosphate (S1P) yet its impact on immune cells remains unclear, despite that all immune cells express specific LPA receptors. Generated systemically through the extracellular enzyme Autotaxin, LPA exerts its biological influence through 6 known G protein couple receptors (GPCRs), LPAR1-6. Aberrant LPA production has been linked to multiple “hallmarks” of tumorigenesis, including enhancing tumor promoting inflammation, metastasis, and angiogenesis. We propose that up regulation of tumor-derived LPA can also dampen adaptive immune responses, thereby creating an immune suppressive tumor microenvironment. CD8+ T cells are known to be able to eliminate nascent tumors, yet over time are often rendered functionally silent due to tumor-derived signals that act on inhibitory receptors such as CTLA4 and PD1. Work from our lab has found that pathological levels of LPA can also dampen TCR signaling suggesting an additional mechanism by which cancers avoid elimination. Strikingly, ablation of LPAR5 on CD8+ T cells significantly reduced tumor burden compared to wild type CD8+ T cells, suggesting that LPAR5 is a novel inhibitory lipid receptor. Given the recent success of checkpoint blockade therapy for the treatment of cancers, we are currently characterizing this novel inhibitory interaction between CD8+ T cells and LPA generated in the tumor microenvironment.
A multikinase inhibitor and DNA-PK inhibitor combination reduces tumor growth and alters the tumor microenvironment of B16 melanoma
Authors: Tsai Alexander , Davila Eduardo 
Published: January 2023

Abstract
Recent breakthroughs in targeted therapies and immunotherapies for melanoma have prolonged survival in certain patients. Yet, many patients are not candidates for targeted therapies and response rates to immunotherapies remain low. Thus, there is an unmet need to develop novel melanoma therapies that generate: the high response rates that are characteristic of targeted therapies, the durable responses often observed with immunotherapies, and can be used in a majority of melanoma patients. Therefore, a high-throughput approach evaluating nearly 2,000 compounds was taken to identify FDA-approved therapies that alter the expression of immunologically relevant molecules commonly found on human melanomas. Eight compounds were identified based on their ability to reduce melanoma proliferation without negatively impacting T cell proliferation and function. Studies examining the expression of immunosuppressive molecules on melanoma, melanoma proliferation, and T cell-melanoma co-cultures were used to select a multikinase inhibitor and DNA-PK inhibitor for further investigation. The compounds sensitized melanoma to T cell cytotoxicity which was associated with increased MHC class I and antigen expression. In mice with established B16 tumors, the therapeutic combination significantly reduced tumor growth while prolonging survival. Preliminary data suggests that the drug combination impacts the tumor microenvironment and alters various immune cells present in the tumor. Studies using alternative models of melanomas and additional therapeutic combinations are ongoing. These studies represent a proof of concept demonstrating the ability to repurpose drugs to immunosensitize tumors to T cell-based therapies.
Epigenetic silencing of TH1-type chemokines shapes tumour immunity and immunotherapy
Authors: Kryczek Ilona , Peng Dongjun , Nagarsheth Nisha B , Zhao Lili , Wei Shuang , Zhao Ende , Vatan Linda , Szeliga Wojciech , Liu Rebecca , Kotarski Jan , Tarkowski Rafal , Wang Weimin , Zou Weiping 
Published: January 2023

Abstract
Epigenetic silencing including histone modifications and DNA methylation is an important tumorigenic mechanism. However, its role in cancer immunopathology and immunotherapy is poorly understood. Using human ovarian cancers as our model, here we show that enhancer of zeste homologue 2 (EZH2)-mediated histone H3 lysine 27 trimethylation (H3K27me3) and DNA methyltransferase 1 (DNMT1)-mediated DNA methylation repress the tumour production of T helper 1 (TH1)-type chemokines CXCL9 and CXCL10, and subsequently determine effector T-cell trafficking to the tumour microenvironment. Treatment with epigenetic modulators removes the repression and increases effector T-cell tumour infiltration, slows down tumour progression, and improves the therapeutic efficacy of programmed death-ligand 1 (PD-L1; also known as B7-H1) checkpoint blockade and adoptive T-cell transfusion in tumour-bearing mice. Moreover, tumour EZH2 and DNMT1 are negatively associated with tumour-infiltrating CD8(+) T cells and patient outcome. Thus, epigenetic silencing of TH1-type chemokines is a novel immune-evasion mechanism of tumours. Selective epigenetic reprogramming alters the T-cell landscape in cancer and may enhance the clinical efficacy of cancer therapy
NF-κB acts as a molecular link between tumor cells and Th1/Tc1 T cells in the tumor microenvironment to exert radiation-mediated tumor suppression.
Authors: Redd Priscilla S , Bardhan Kankana , Chen May R , Paschall Amy V , Lu Chunwan , Bollag Roni J , Kong Fengchong , Jin JianYue , Kong Feng-Ming , Waller Jennifer L , Pollock Raphael E , Liu Kebin 
Published: January 2023

Abstract
Radiation is a local treatment for many types of solid cancers. About two thirds of cancer patients require radiation during the course of their disease treatment. Radiation modulates both tumor cells and immune cells in the tumor microenvironment to exert anti-tumor activity, but the molecular connection between tumor cells and immune cells that mediates radiation-exerted tumor suppression activity is largely unknown. We report here that radiation induces rapid activation of the p65/p50 and p50/p50 NF-κB complexes in human soft tissue sarcoma (STS) cells. Radiation-activated p65/p50 and p50/p50 bind to the TNFα promoter to activate its transcription in STS cells. Radiation-induced TNFα then induces tumor cell death in an autocrine manner. Smac mimetic BV6 induces cIAP1 and cIAP2 degradation to increase tumor cell sensitivity to radiation-induced cell death in vitro and to enhance radiation-mediated suppression of STS xenografts in vivo. Inhibition of caspases, RIP1, or RIP3 blocks radiation/TNFα-induced cell death, whereas inhibition of RIP1 blocks TNFα-induced caspase activation, suggesting that caspases and RIP1 act sequentially to mediate the non-compensatory cell death pathways. We determined in a syngeneic sarcoma mouse model that radiation up-regulates the NF-κB target genes IRF3, IFNβ, and the T cell chemokines CCL2 and CCL5 in the tumor microenvironment, which is associated with activation and increased infiltration of Th1/Tc1 T cells in the tumor microenvironment. Consequently, combined BV6 and radiation completely suppressed tumor growth in vivo. Radiation-induced NF-κB functions as a molecular link between tumor cells and immune cells in the tumor microenvironment for radiation mediated tumor suppression.
Following the fate of genetically modified T cells in melanoma patients
Authors: Moore Tamson V , Scurti Gina , Regan Courtney , Hutchens Kelli , Godellas Constatine , Clark Ann Lau , Moxley Kelly , Dropulic Boro , Embree Heather , Shirai Keisuke , Garrett-Mayer Elizabeth , Li Mingli , Eby Jonathan , Clark Joseph I. , Le Poole Caroline , Nishimura Michael I. 
Published: January 2023

Abstract
In an open clinical trial for Stage IV melanoma patients, we are testing a promising new therapy in which the patient’s own T cells are genetically engineered with a T cell receptor (TIL 1383I TCR) targeting the melanoma antigen tyrosinase. Included in the TIL 1383I TCR vector is a nonfunctional CD34 marker that can be readily tracked by flow cytometry. These transgenic T cells are infused into the patient with the goals of killing tumor cells and promoting anti-tumor inflammatory responses.
We find that the transgenic T cells persist at low levels for at least twenty months in vivo. Many of the transgenic T cells are activated in the patient, indicating that they are responding to antigen. A subset of activated cells express inhibitory receptors, including PD-1 and CTLA-4. Upon further analysis of patient samples, we found that the percent of transgene-expressing T cells can be increased up to three-fold with either cytokine stimulation and/or CD3/CD28-bead stimulation.
When cultured in vitro, transduced T cells lose transgene expression over time, and culturing in the absence of cytokines dramatically increases the rate of transgene expression loss. As seen ex vivo, restimulation of in vitro cultured T cells restores transgene expression. Cells undergoing division express substantially more transgene than resting cells. These data suggest that mitogenic factors causing cell division may promote transgene expression. We next plan to test mitogenic (high dose IL-2, IL-15) and anti-inhibition (PD-1 and CTLA-4 blockade) therapies with T cell transfer utilizing murine mouse models and potentially amend our protocol in the future to reduce the effects of exhaustion and transgene loss on transgenic anti-tumor T cells.
Toll-like receptor agonist therapy augments the antitumor activity of adoptively transferred CD8+ T cells without host preconditioning
Authors: Paulos Chrystal M , Bowers Jacob S , Bailey Stefanie R , Diven Marshall A , Fugle Caroline W , Kaiser Andrew D , Wrzesinski Claudia , Liu Bei , Restifo Nicholas P , Nelson Michelle 
Published: January 2023

Abstract
Lymphodepletion enhances adoptive T cell transfer (ACT) therapy by activating the innate immune system via microbes released from the radiation-injured gut. Microbial LPS is a key mediator of lymphodepletion enhancement, but our ability to use these TLR agonists to bolster the potency of T cell-based cancer therapies remains elusive. Herein, we used LPS as a tool to address how and when to use TLR agonists to improve cancer immunotherapy. We utilized the pmel-1 melanoma mouse model. B16F10-bearing mice were lymphodepleted with 5Gy total body irradiation (TBI) and given a tripartite ACT therapy (consisting of transferred pmel-1 CD8+ T cells, vaccination with fowlpox encoding gp100, and IL-2) along with TLR4 agonist LPS. The timing of LPS administration and the requirement of individual components of the tripartite therapy were evaluated. We discovered that while exogenous administration of LPS was able to enhance CD8+ T cells’ tumor destruction, LPS treatment alone did not replace individual components of the tripartite regimen. Interestingly, administering LPS one day before ACT compromised tumor regression. Conversely, administering LPS after ACT potentiated the antitumor effectiveness of the regimen, thereby supporting the expansion of transferred CD8+ T cells over host Treg cells. Non-toxic TLR agonists MPL and CpG also improved ACT therapy. Finally, TBI preconditioning was no longer needed to regress tumors in mice depleted of host CD4+ T cells, given a tripartite ACT regimen and then treated with a TLR agonist. Collectively, our results identify how and when to administer TLR agonists to augment ACT in the absence of host preconditioning. These findings have implications for the design of next generation T cell therapies.
First generation CAR-T therapies can be rendered therapeutically effective when engineered into a novel human CD26high CD4+ T cell
Authors: Nelson Michelle , Bailey Stefanie R , Huff Logan , Bowers Jacob , Paulos Chrystal M 
Published: January 2023

Abstract
Despite a few very exciting results from adoptive cell transfer (ACT) therapy-based clinical trials, most studies have infused less than ideal cell populations into patients. Human CD4+ T cells differentiate into multiple effector subsets, but their distinct roles in anti-tumor immunity remain elusive. Interestingly, we found that CD26high CD4+ T cells were more polyfunctional than the other CD4+ T cells subsets- with increased production of IL-17, IFN-γ, IL-22 and TNF-α. Additionally, CD26high T cells had increased expression of anti-apoptotic molecules c-flip, bcl2, AKT and CEBPD. Moreover, CD26high T cells had a more pathogenic phenotype compared to Th17 cells. To test the therapeutic potential, cells were genetically redirected to recognize human mesothelioma using a 1st generation chimeric antigen receptor (CAR, scFv from monoclonal antibodies that are linked to the CD3z intracellular signaling domain of the TCR complex). To date, effective antitumor responses were only seen in 2nd generation CARs with additional costimulatory molecules. Surprisingly, 1st generation CAR-engineered CD26high T cells possessed a superior ability to kill large human tumors when infused into NSG mice compared to Th1, Th2 or Th17 cells. Furthermore, CD26high T cells strongly bolster infused CD8+ T cells, as seen by an increase in both cell number and functionality. Contrary to Th17 cells, CD26high T cells do not require CD8+ T cells to aid in tumor killing, as the antitumor response was similar with or without CD8+ T cell infusion. These results suggest that the generation of multifunctional, long-lived human CD26high T cells could be instrumental to the design of novel, effective T cell-based therapies, targeted to any number of malignancies.