bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Tumor Mutation Burden and Structural Chromosomal Aberrations Are Not Associated with T-cell Density or Patient Survival in Acral, Mucosal, and Cutaneous Melanomas
Authors: Edwards Jarem , Ferguson Peter M. , Lo Serigne N. , Pires da Silva Inês , Colebatch Andrew J. , Lee Hansol , Saw Robyn P.M. , Thompson John F. , Menzies Alexander M. , Long Georgina V. , Newell Felicity , Pearson John V. , Waddell Nicola , Hayward Nicholas K. , Johansson Peter A. , Mann Graham J. , Scolyer Richard A. , Palendira Umaimainthan , Wilmott James S.
Published: April 2023

Abstract
Tumor mutation burden (TMB) has been proposed as a key determinant of immunogenicity in several cancers, including melanoma. The evidence presented thus far, however, is often contradictory and based mostly on RNA-sequencing data for the quantification of immune cell phenotypes. Few studies have investigated TMB across acral, mucosal, and cutaneous melanoma subtypes, which are known to have different TMB. It is also unknown whether chromosomal structural mutations [structural variant (SV) mutations] contribute to the immunogenicity in acral and mucosal melanomas where such aberrations are common. We stained 151 cutaneous and 35 acral and mucosal melanoma patient samples using quantitative IHC and correlated immune infiltrate phenotypes with TMB and other genomic profiles. TMB and SVs did not correlate with the densities of CD8+ lymphocytes, CD103+ tumor-resident T cells (Trm), CD45RO+ cells, and other innate and adaptive immune cell subsets in cutaneous and acral/mucosal melanoma tumors, respectively, including in analyses restricted to the site of disease and in a validation cohort. In 43 patients with stage III treatment-naïve cutaneous melanoma, we found that the density of immune cells, particularly Trm, was significantly associated with patient survival, but not with TMB. Overall, TMB and chromosomal structural aberrations are not associated with protective antitumor immunity in treatment-naïve melanoma.
Data from Combined Vaccination with NY-ESO-1 Protein, Poly-ICLC, and Montanide Improves Humoral and Cellular Immune Responses in Patients with High-Risk Melanoma
Authors: Pavlick Anna , Blazquez Ana B. , Meseck Marcia , Lattanzi Michael , Ott Patrick A. , Marron Thomas U. , Holman Rose Marie , Mandeli John , Salazar Andres M. , McClain Christopher B. , Gimenez Gustavo , Balan Sreekumar , Gnjatic Sacha , Sabado Rachel Lubong , Bhardwaj Nina
Published: April 2023

Abstract
Given its ability to induce both humoral and cellular immune responses, NY-ESO-1 has been considered a suitable antigen for a cancer vaccine. Despite promising results from early-phase clinical studies in patients with melanoma, NY-ESO-1 vaccine immunotherapy has not been widely investigated in larger trials; consequently, many questions remain as to the optimal vaccine formulation, predictive biomarkers, and sequencing and timing of vaccines in melanoma treatment. We conducted an adjuvant phase I/II clinical trial in high-risk resected melanoma to optimize the delivery of poly-ICLC, a TLR-3/MDA-5 agonist, as a component of vaccine formulation. A phase I dose-escalation part was undertaken to identify the MTD of poly-ICLC administered in combination with NY-ESO-1 and montanide. This was followed by a randomized phase II part investigating the MTD of poly-ICLC with NY-ESO-1 with or without montanide. The vaccine regimens were generally well tolerated, with no treatment-related grade 3/4 adverse events. Both regimens induced integrated NY-ESO-1–specific CD4+ T-cell and humoral responses. CD8+ T-cell responses were mainly detected in patients receiving montanide. T-cell avidity toward NY-ESO-1 peptides was higher in patients vaccinated with montanide. In conclusion, NY-ESO-1 protein in combination with poly-ICLC is safe, well tolerated, and capable of inducing integrated antibody and CD4+ T-cell responses in most patients. Combination with montanide enhances antigen-specific T-cell avidity and CD8+ T-cell cross-priming in a fraction of patients, indicating that montanide contributes to the induction of specific CD8+ T-cell responses to NY-ESO-1.
Data from Transient Depletion of CD4+ Cells Induces Remodeling of the TCR Repertoire in Gastrointestinal Cancer
Authors: Aoki Hiroyasu , Ueha Satoshi , Shichino Shigeyuki , Ogiwara Haru , Shitara Kohei , Shimomura Manami , Suzuki Toshihiro , Nakatsura Tetsuya , Yamashita Makiko , Kitano Shigehisa , Kuroda Sakiko , Wakabayashi Masashi , Kurachi Makoto , Ito Satoru , Doi Toshihiko , Matsushima Kouji
Published: April 2023

Abstract
Antibody-mediated transient depletion of CD4+ cells enhances the expansion of tumor-reactive CD8+ T cells and exhibits robust antitumor effects in preclinical and clinical studies. To investigate the clonal T-cell responses following transient CD4+ cell depletion in patients with cancer, we conducted a temporal analysis of the T-cell receptor (TCR) repertoire in the first-in-human clinical trial of IT1208, a defucosylated humanized monoclonal anti-CD4. Transient depletion of CD4+ cells promoted replacement of T-cell clones among CD4+ and CD8+ T cells in the blood. This replacement of the TCR repertoire was associated with the extent of CD4+ T-cell depletion and an increase in CD8+ T-cell count in the blood. Next, we focused on T-cell clones overlapping between the blood and tumor in order to track tumor-associated T-cell clones in the blood. The total frequency of blood–tumor overlapping clones tended to increase in patients receiving a depleting dose of anti-CD4, which was accompanied by the replacement of overlapping clones. The greater expansion of CD8+ overlapping clones was commonly observed in the patients who achieved tumor shrinkage. These results suggested that the clonal replacement of the TCR repertoire induced by transient CD4+ cell depletion was accompanied by the expansion of tumor-reactive T-cell clones that mediated antitumor responses. Our findings propose beneficial remodeling of the TCR repertoire following transient CD4+ cell depletion and provide novel insight into the antitumor effects of monoclonal anti-CD4 treatment in patients with cancer.

See related Spotlight on p. 601
Data from An Antibody Targeting ICOS Increases Intratumoral Cytotoxic to Regulatory T-cell Ratio and Induces Tumor Regression
Authors: Sainson Richard C.A. , Thotakura Anil K. , Kosmac Miha , Borhis Gwenoline , Parveen Nahida , Kimber Rachael , Carvalho Joana , Henderson Simon J. , Pryke Kerstin L. , Okell Tracey , O'Leary Siobhan , Ball Stuart , Van Krinks Cassie , Gamand Lauriane , Taggart Emma , Pring Eleanor J. , Ali Hanif , Craig Hannah , Wong Vivian W.Y. , Liang Qi , Rowlands Robert J. , Lecointre Morgane , Campbell Jamie , Kirby Ian , Melvin David , Germaschewski Volker , Oelmann Elisabeth , Quaratino Sonia , McCourt Matthew
Published: April 2023

Abstract
The immunosuppressive tumor microenvironment constitutes a significant hurdle to immune checkpoint inhibitor responses. Both soluble factors and specialized immune cells, such as regulatory T cells (Treg), are key components of active intratumoral immunosuppression. Inducible costimulatory receptor (ICOS) can be highly expressed in the tumor microenvironment, especially on immunosuppressive Treg, suggesting that it represents a relevant target for preferential depletion of these cells. Here, we performed immune profiling of samples from tumor-bearing mice and patients with cancer to demonstrate differential expression of ICOS in immune T-cell subsets in different tissues. ICOS expression was higher on intratumoral Treg than on effector CD8 T cells. In addition, by immunizing an Icos knockout transgenic mouse line expressing antibodies with human variable domains, we selected a fully human IgG1 antibody called KY1044 that bound ICOS from different species. We showed that KY1044 induced sustained depletion of ICOShigh T cells but was also associated with increased secretion of proinflammatory cytokines from ICOSlow effector T cells (Teff). In syngeneic mouse tumor models, KY1044 depleted ICOShigh Treg and increased the intratumoral TEff:Treg ratio, resulting in increased secretion of IFNγ and TNFα by TEff cells. KY1044 demonstrated monotherapy antitumor efficacy and improved anti–PD-L1 efficacy. In summary, we demonstrated that using KY1044, one can exploit the differential expression of ICOS on T-cell subtypes to improve the intratumoral immune contexture and restore an antitumor immune response.
Data from Deciphering the Immunomodulatory Capacity of Oncolytic Vaccinia Virus to Enhance the Immune Response to Breast Cancer
Authors: Umer Brittany A. , Noyce Ryan S. , Franczak Brian C. , Shenouda Mira M. , Kelly Rees G. , Favis Nicole A. , Desaulniers Megan , Baldwin Troy A. , Hitt Mary M. , Evans David H.
Published: April 2023

Abstract
Vaccinia virus (VACV) is a double-stranded DNA virus that devotes a large portion of its 200 kbp genome to suppressing and manipulating the immune response of its host. Here, we investigated how targeted removal of immunomodulatory genes from the VACV genome impacted immune cells in the tumor microenvironment with the intention of improving the therapeutic efficacy of VACV in breast cancer. We performed a head-to-head comparison of six mutant oncolytic VACVs, each harboring deletions in genes that modulate different cellular pathways, such as nucleotide metabolism, apoptosis, inflammation, and chemokine and interferon signaling. We found that even minor changes to the VACV genome can impact the immune cell compartment in the tumor microenvironment. Viral genome modifications had the capacity to alter lymphocytic and myeloid cell compositions in tumors and spleens, PD-1 expression, and the percentages of virus-targeted and tumor-targeted CD8+ T cells. We observed that while some gene deletions improved responses in the nonimmunogenic 4T1 tumor model, very little therapeutic improvement was seen in the immunogenic HER2/neu TuBo model with the various genome modifications. We observed that the most promising candidate genes for deletion were those that interfere with interferon signaling. Collectively, this research helped focus attention on the pathways that modulate the immune response in the context of VACV oncolytic virotherapy. They also suggest that the greatest benefits to be obtained with these treatments may not always be seen in “hot tumors.”
Data from CRASH-IT Switch Enables Reversible and Dose-Dependent Control of TCR and CAR T-cell Function
Authors: Sahillioglu Ali Can , Toebes Mireille , Apriamashvili Georgi , Gomez Raquel , Schumacher Ton N.
Published: April 2023

Abstract
Adoptive transfer of genetically modified or donor-derived T cells can efficiently eradicate human tumors but is also frequently associated with major toxicity. There are several switches that can be used to kill the infused cell pool in the case of major toxicity, but the irreversible nature of these suicide switches means that the therapeutic effect is lost when they are used. To address this issue, we engineered a small-molecule responsive genetic safety switch that in the absence of drug robustly blocked cytotoxicity and cytokine expression of primary human T cells. Upon administration of drug, T-cell functions were restored in a reversible and titratable manner. We showed that this T-cell switch was universal, as it could be combined with endogenous or transduced T-cell receptors (TCR), as well as chimeric antigen receptors. The modular nature of the Chemically Regulated - SH2-delivered Inhibitory Tail (CRASH-IT) switch concept, in which inhibitory domains are brought to activating immune receptors in a controlled manner, makes it a versatile platform to regulate the activity of cell products that signal through immunoreceptor tyrosine-based activation motif (ITAM)–containing receptors.
Data from γδ T Cells in Merkel Cell Carcinomas Have a Proinflammatory Profile Prognostic of Patient Survival
Authors: Gherardin Nicholas A. , Waldeck Kelly , Caneborg Alex , Martelotto Luciano G. , Balachander Shiva , Zethoven Magnus , Petrone Pasquale M. , Pattison Andrew , Wilmott James S. , Quiñones-Parra Sergio M. , Rossello Fernando , Posner Atara , Wong Annie , Weppler Alison M. , Shannon Kerwin F. , Hong Angela , Ferguson Peter M. , Jakrot Valerie , Raleigh Jeanette , Hatzimihalis Athena , Neeson Paul J. , Deleso Paolo , Johnston Meredith , Chua Margaret , Becker Juergen C. , Sandhu Shahneen , McArthur Grant A. , Gill Anthony J. , Scolyer Richard A. , Hicks Rodney J. , Godfrey Dale I. , Tothill Richard W.
Published: April 2023

Abstract
Merkel cell carcinomas (MCC) are immunogenic skin cancers associated with viral infection or UV mutagenesis. To study T-cell infiltrates in MCC, we analyzed 58 MCC lesions from 39 patients using multiplex-IHC/immunofluorescence (m-IHC/IF). CD4+ or CD8+ T cells comprised the majority of infiltrating T lymphocytes in most tumors. However, almost half of the tumors harbored prominent CD4/CD8 double-negative (DN) T-cell infiltrates (>20% DN T cells), and in 12% of cases, DN T cells represented the majority of T cells. Flow cytometric analysis of single-cell suspensions from fresh tumors identified DN T cells as predominantly Vδ2− γδ T cells. In the context of γδ T–cell inflammation, these cells expressed PD-1 and LAG3, which is consistent with a suppressed or exhausted phenotype, and CD103, which indicates tissue residency. Furthermore, single-cell RNA sequencing (scRNA-seq) identified a transcriptional profile of γδ T cells suggestive of proinflammatory potential. T-cell receptor (TCR) analysis confirmed clonal expansion of Vδ1 and Vδ3 clonotypes, and functional studies using cloned γδ TCRs demonstrated restriction of these for CD1c and MR1 antigen-presenting molecules. On the basis of a 13-gene γδ T–cell signature derived from scRNA-seq analysis, gene-set enrichment on bulk RNA-seq data showed a positive correlation between enrichment scores and DN T-cell infiltrates. An improved disease-specific survival was evident for patients with high enrichment scores, and complete responses to anti–PD-1/PD-L1 treatment were observed in three of four cases with high enrichment scores. Thus, γδ T–cell infiltration may serve as a prognostic biomarker and should be explored for therapeutic interventions.

See related Spotlight on p. 600
Data from Prognostic Integrated Image-Based Immune and Molecular Profiling in Early-Stage Endometrial Cancer
Authors: Horeweg Nanda , de Bruyn Marco , Nout Remi A. , Stelloo Ellen , Kedzierska Katarzyna , León-Castillo Alicia , Plat Annechien , Mertz Kirsten D. , Osse Michelle , Jürgenliemk-Schulz Ina M. , Lutgens Ludy C.H.W. , Jobsen Jan J. , van der Steen-Banasik Elzbieta M. , Smit Vincent T. , Creutzberg Carien L. , Bosse Tjalling , Nijman Hans W. , Koelzer Viktor H. , Church David N.
Published: April 2023

Abstract
Optimum risk stratification in early-stage endometrial cancer combines clinicopathologic factors and the molecular endometrial cancer classification defined by The Cancer Genome Atlas (TCGA). It is unclear whether analysis of intratumoral immune infiltrate improves this. We developed a machine-learning, image-based algorithm to quantify density of CD8+ and CD103+ immune cells in tumor epithelium and stroma in 695 stage I endometrioid endometrial cancers from the PORTEC-1 and -2 trials. The relationship between immune cell density and clinicopathologic/molecular factors was analyzed by hierarchical clustering and multiple regression. The prognostic value of immune infiltrate by cell type and location was analyzed by univariable and multivariable Cox regression, incorporating the molecular endometrial cancer classification. Tumor-infiltrating immune cell density varied substantially between cases, and more modestly by immune cell type and location. Clustering revealed three groups with high, intermediate, and low densities, with highly significant variation in the proportion of molecular endometrial cancer subgroups between them. Univariable analysis revealed intraepithelial CD8+ cell density as the strongest predictor of endometrial cancer recurrence; multivariable analysis confirmed this was independent of pathologic factors and molecular subgroup. Exploratory analysis suggested this association was not uniform across molecular subgroups, but greatest in tumors with mutant p53 and absent in DNA mismatch repair–deficient cancers. Thus, this work identified that quantification of intraepithelial CD8+ cells improved upon the prognostic utility of the molecular endometrial cancer classification in early-stage endometrial cancer.
Data from Idelalisib Rescues Natural Killer Cells from Monocyte-Induced Immunosuppression by Inhibiting NOX2-Derived Reactive Oxygen Species
Authors: Akhiani Ali A. , Hallner Alexander , Kiffin Roberta , Aydin Ebru , Werlenius Olle , Aurelius Johan , Martner Anna , Thorén Fredrik B. , Hellstrand Kristoffer
Published: April 2023

Abstract
The phosphatidylinositol-4,5-bisphosphate-3 kinase-δ (PI3Kδ) inhibitor idelalisib, used alone or in combination with anti-CD20, is clinically efficacious in B-cell lymphoma and chronic lymphocytic leukemia (CLL) by promoting apoptosis of malignant B cells. PI3K regulates the formation of reactive oxygen species (ROS) by the myeloid NADPH oxidase NOX2, but the role of PI3Kδ in myeloid cell–induced immunosuppression is unexplored. We assessed the effects of idelalisib on the spontaneous and IgG antibody–induced ROS production by human monocytes, on ROS-induced cell death of human natural killer (NK) cells, and on tumor cell clearance in an NK cell–dependent mouse model of metastasis. Idelalisib potently and efficiently inhibited the formation of NOX2-derived ROS from monocytes and rescued NK cells from ROS-induced cell death. Idelalisib also promoted NK cell cytotoxicity against anti–CD20-coated primary human CLL cells and cultured malignant B cells. Experiments using multiple PI3K inhibitors implicated the PI3Kδ isoform in regulating NOX2-induced ROS formation and immunosuppression. In B6 mice, systemic treatment with idelalisib significantly reduced the formation of lung metastases from intravenously injected melanoma cells but did not affect metastasis in B6.129S6-Cybbtm1Din (Nox2−/−) mice or in NK cell–deficient mice. Our results imply that idelalisib rescues NK cells from NOX2/ROS-dependent immunosuppression and thus exerts antineoplastic efficacy beyond B-cell inhibition.
Data from Antitumor Effects of CAR T Cells Redirected to the EDB Splice Variant of Fibronectin
Authors: Wagner Jessica , Wickman Elizabeth , Shaw Timothy I. , Anido Alejandro Allo , Langfitt Deanna , Zhang Jinghui , Porter Shaina N. , Pruett-Miller Shondra M. , Tillman Heather , Krenciute Giedre , Gottschalk Stephen
Published: April 2023

Abstract
Chimeric antigen receptor (CAR) T-cell therapy has had limited success in early-phase clinical studies for solid tumors. Lack of efficacy is most likely multifactorial, including a limited array of targetable antigens. We reasoned that targeting the cancer-specific extra domain B (EDB) splice variant of fibronectin might overcome this limitation because it is abundantly secreted by cancer cells and adheres to their cell surface. In vitro, EDB-CAR T cells recognized and killed EDB-positive tumor cells. In vivo, 1 × 106 EDB-CAR T cells had potent antitumor activity in both subcutaneous and systemic tumor xenograft models, resulting in a significant survival advantage in comparison with control mice. EDB-CAR T cells also targeted the tumor vasculature, as judged by IHC and imaging, and their antivascular activity was dependent on the secretion of EDB by tumor cells. Thus, targeting tumor-specific splice variants such as EDB with CAR T cells is feasible and has the potential to improve the efficacy of CAR T-cell therapy.
Data from CD137/OX40 Bispecific Antibody Induces Potent Antitumor Activity that Is Dependent on Target Coengagement
Authors: Gaspar Miguel , Pravin John , Rodrigues Leonor , Uhlenbroich Sandra , Everett Katy L. , Wollerton Francisca , Morrow Michelle , Tuna Mihriban , Brewis Neil
Published: April 2023

Abstract
Following the success of immune checkpoint blockade therapy against cancer, agonistic antibodies targeting T-cell costimulatory pathways are in clinical trials. The TNF superfamily of receptors (TNFRSF) members CD137 and OX40 are costimulatory receptors that stimulate T-cell proliferation and activation upon interaction with their cognate ligands. Activating CD137 and OX40 with agonistic mAbs stimulates the immune system due to their broad expression on CD4+ and CD8+ T cells and natural killer cells and has antitumor effects in preclinical models. Most TNFRSF agonist antibodies require crosslinking via Fcγ receptors (FcγR), which can limit their clinical activity. FS120 mAb2, a dual agonist bispecific antibody targeting CD137 and OX40, activated both CD4+ and CD8+ T cells in an FcγR-independent mechanism, dependent on concurrent binding. A mouse surrogate version of the bispecific antibody displayed antitumor activity in syngeneic tumor models, independent of T regulatory cell depletion and of FcγR interaction, but associated with peripheral T-cell activation and proliferation. When compared with a crosslink-independent CD137 agonist mAb, the FS120 surrogate induced lower liver T-cell infiltration. These data support initiation of clinical development of FS120, a first-in-class dual agonist bispecific antibody for the treatment of human cancer.
Data from Characterization of BAY 1905254, an Immune Checkpoint Inhibitor Targeting the Immunoglobulin-Like Domain Containing Receptor 2 (ILDR2)
Authors: Huetter Julia , Gritzan Uwe , Gutcher Ilona , Doecke Wolf-Dietrich , Luetke-Eversloh Merlin V. , Golfier Sven , Roider Helge G. , Frisk Anna-Lena , Hunter John , Pow Andrew , Drake Andrew , Levine Zurit , Levy Ofer , Azulay Meir , Barbiro Inbal , Cojocaru Gady , Vaknin Ilan , Kreft Bertolt , Roese Lars
Published: April 2023

Abstract
The immunoglobulin-like domain containing receptor 2 (ILDR2), a type I transmembrane protein belonging to the B7 family of immunomodulatory receptors, has been described to induce an immunosuppressive effect on T-cell responses. Besides its expression in several nonlymphoid tissue types, we found that ILDR2 was also expressed in fibroblastic reticular cells (FRC) in the stromal part of the lymph node. These immunoregulatory cells were located in the T-cell zone and were essential for the recruitment of naïve T cells and activated dendritic cells to the lymph nodes. Previously, it has been shown that an ILDR2-Fc fusion protein exhibits immunomodulatory effects in several models of autoimmune diseases, such as multiple sclerosis, rheumatoid arthritis, and type I diabetes. Herein, we report the generation and characterization of a human/mouse/monkey cross-reactive anti-ILDR2 hIgG2 antibody, BAY 1905254, developed to block the immunosuppressive activity of ILDR2 for cancer immunotherapy. BAY 1905254 was shown to promote T-cell activation in vitro and enhance antigen-specific T-cell proliferation and cytotoxicity in vivo in mice. BAY 1905254 also showed potent efficacy in various syngeneic mouse cancer models, and the efficacy was found to correlate with increasing mutational load in the cancer models used. Additive or even synergistic antitumor effects were observed when BAY 1905254 was administered in combination with anti–PD-L1, an immunogenic cell death–inducing chemotherapeutic, or with tumor antigen immunization. Taken together, our data showed that BAY 1905254 is a potential drug candidate for cancer immunotherapy, supporting its further evaluation.
Data from Pharmacologic Screening Identifies Metabolic Vulnerabilities of CD8+ T Cells
Authors: Drijvers Jefte M. , Gillis Jacob E. , Muijlwijk Tara , Nguyen Thao H. , Gaudiano Emily F. , Harris Isaac S. , LaFleur Martin W. , Ringel Alison E. , Yao Cong-Hui , Kurmi Kiran , Juneja Vikram R. , Trombley Justin D. , Haigis Marcia C. , Sharpe Arlene H.
Published: April 2023

Abstract
Metabolic constraints in the tumor microenvironment constitute a barrier to effective antitumor immunity and similarities in the metabolic properties of T cells and cancer cells impede the specific therapeutic targeting of metabolism in either population. To identify distinct metabolic vulnerabilities of CD8+ T cells and cancer cells, we developed a high-throughput in vitro pharmacologic screening platform and used it to measure the cell type–specific sensitivities of activated CD8+ T cells and B16 melanoma cells to a wide array of metabolic perturbations during antigen-specific killing of cancer cells by CD8+ T cells. We illustrated the applicability of this screening platform by showing that CD8+ T cells were more sensitive to ferroptosis induction by inhibitors of glutathione peroxidase 4 (GPX4) than B16 and MC38 cancer cells. Overexpression of ferroptosis suppressor protein 1 (FSP1) or cytosolic GPX4 yielded ferroptosis-resistant CD8+ T cells without compromising their function, while genetic deletion of the ferroptosis sensitivity–promoting enzyme acyl-CoA synthetase long-chain family member 4 (ACSL4) protected CD8+ T cells from ferroptosis but impaired antitumor CD8+ T-cell responses. Our screen also revealed high T cell–specific vulnerabilities for compounds targeting NAD+ metabolism or autophagy and endoplasmic reticulum (ER) stress pathways. We focused the current screening effort on metabolic agents. However, this in vitro screening platform may also be valuable for rapid testing of other types of compounds to identify regulators of antitumor CD8+ T-cell function and potential therapeutic targets.
Data from Blockade of Immune-Checkpoint B7-H4 and Lysine Demethylase 5B in Esophageal Squamous Cell Carcinoma Confers Protective Immunity against P. gingivalis Infection
Authors: Yuan Xiang , Liu Yiwen , Li Guifang , Lan Zijun , Ma Mingyang , Li Huaxu , Kong Jinyu , Sun Jiangtao , Hou Gaochao , Hou Xurong , Ma Yingjian , Ren Feng , Zhou Fuyou , Gao Shegan
Published: April 2023

Abstract
Pathogens are capable of hijacking immune defense mechanisms, thereby creating a tolerogenic environment for hypermutated malignant cells that arise within the site of infection. Immune checkpoint–oriented immunotherapies have shown considerable promise. Equally important, the epigenetic reprogramming of an immune-evasive phenotype that activates the immune system in a synergistic manner can improve immunotherapy outcomes. These advances have led to combinations of epigenetic- and immune-based therapeutics. We previously demonstrated that Porphyromonas gingivalis isolated from esophageal squamous cell carcinoma (ESCC) lesions represents a major pathogen associated with this deadly disease. In this study, we examined the mechanisms associated with host immunity during P. gingivalis infection and demonstrated that experimentally infected ESCC responds by increasing the expression of B7-H4 and lysine demethylase 5B, which allowed subsequent in vivo analysis of the immunotherapeutic effects of anti–B7-H4 and histone demethylase inhibitors in models of chronic infection and immunity against xenografted human tumors. Using three different preclinical mouse models receiving combined therapy, we showed that mice mounted strong resistance against P. gingivalis infection and tumor challenge. This may have occurred via generation of a T cell–mediated response in the microenvironment and formation of immune memory. In ESCC subjects, coexpression of B7-H4 and KDM5B correlated more significantly with bacterial load than with the expression of either molecule alone. These results highlight the unique ability of P. gingivalis to evade immunity and define potential targets that can be exploited therapeutically to improve the control of P. gingivalis infection and the development of associated neoplasia.
Data from Combined BRAF, MEK, and CDK4/6 Inhibition Depletes Intratumoral Immune-Potentiating Myeloid Populations in Melanoma
Authors: Lelliott Emily J. , Mangiola Stefano , Ramsbottom Kelly M. , Zethoven Magnus , Lim Lydia , Lau Peter K.H. , Oliver Amanda J. , Martelotto Luciano G. , Kirby Laura , Martin Claire , Patel Riyaben P. , Slater Alison , Cullinane Carleen , Papenfuss Anthony T. , Haynes Nicole M. , McArthur Grant A. , Oliaro Jane , Sheppard Karen E.
Published: April 2023

Abstract
Combined inhibition of BRAF, MEK, and CDK4/6 is currently under evaluation in clinical trials for patients with melanoma harboring a BRAFV600 mutation. While this triple therapy has potent tumor-intrinsic effects, the impact of this combination on antitumor immunity remains unexplored. Here, using a syngeneic BrafV600ECdkn2a−/−Pten−/− melanoma model, we demonstrated that triple therapy promoted durable tumor control through tumor-intrinsic mechanisms and promoted immunogenic cell death and T-cell infiltration. Despite this, tumors treated with triple therapy were unresponsive to immune checkpoint blockade (ICB). Flow cytometric and single-cell RNA sequencing analyses of tumor-infiltrating immune populations revealed that triple therapy markedly depleted proinflammatory macrophages and cross-priming CD103+ dendritic cells, the absence of which correlated with poor overall survival and clinical responses to ICB in patients with melanoma. Indeed, immune populations isolated from tumors of mice treated with triple therapy failed to stimulate T-cell responses ex vivo. While combined BRAF, MEK, and CDK4/6 inhibition demonstrates favorable tumor-intrinsic activity, these data suggest that collateral effects on tumor-infiltrating myeloid populations may impact antitumor immunity. These findings have important implications for the design of combination strategies and clinical trials that incorporate BRAF, MEK, and CDK4/6 inhibition with immunotherapy for the treatment of patients with melanoma.
Data from Mammalian SWI/SNF Complex Genomic Alterations and Immune Checkpoint Blockade in Solid Tumors
Authors: Abou Alaiwi Sarah , Nassar Amin H. , Xie Wanling , Bakouny Ziad , Berchuck Jacob E. , Braun David A. , Baca Sylvan C. , Nuzzo Pier Vitale , Flippot Ronan , Mouhieddine Tarek H. , Spurr Liam F. , Li Yvonne Y. , Li Taiwen , Flaifel Abdallah , Steinharter John A. , Margolis Claire A. , Vokes Natalie I. , Du Heng , Shukla Sachet A. , Cherniack Andrew D. , Sonpavde Guru , Haddad Robert I. , Awad Mark M. , Giannakis Marios , Hodi F. Stephen , Liu X. Shirley , Signoretti Sabina , Kadoch Cigall , Freedman Matthew L. , Kwiatkowski David J. , Van Allen Eliezer M. , Choueiri Toni K.
Published: April 2023

Abstract
Prior data have variably implicated the inactivation of the mammalian SWItch/Sucrose Non-Fermentable (mSWI/SNF) complex with increased tumor sensitivity to immune checkpoint inhibitors (ICI). Herein, we examined the association between mSWI/SNF variants and clinical outcomes to ICIs. We correlated somatic loss-of-function (LOF) variants in a predefined set of mSWI/SNF genes (ARID1A, ARID1B, SMARCA4, SMARCB1, PBRM1, and ARID2) with clinical outcomes in patients with cancer treated with systemic ICIs. We identified 676 patients from Dana-Farber Cancer Institute (DFCI, Boston, MA) and 848 patients from a publicly available database from Memorial Sloan Kettering Cancer Center (MSKCC, New York, NY) who met the inclusion criteria. Multivariable analyses were conducted and adjusted for available baseline factors and tumor mutational burden. Median follow-up was 19.6 (17.6–22.0) months and 28.0 (25.0–29.0) months for the DFCI and MSKCC cohorts, respectively. Seven solid tumor subtypes were examined. In the DFCI cohort, LOF variants of mSWI/SNF did not predict improved overall survival (OS), time-to-treatment failure (TTF), or disease control rate. Only patients with renal cell carcinoma with mSWI/SNF LOF showed significantly improved OS and TTF with adjusted HRs (95% confidence interval) of 0.33 (0.16–0.7) and 0.49 (0.27–0.88), respectively, and this was mostly driven by PRBM1. In the MSKCC cohort, where only OS was captured, LOF mSWI/SNF did not correlate with improved outcomes across any tumor subtype. We did not find a consistent association between mSWI/SNF LOF variants and improved clinical outcomes to ICIs, suggesting that mSWI/SNF variants should not be considered as biomarkers of response to ICIs.
Data from Inhibition of MICA and MICB Shedding Elicits NK-Cell–Mediated Immunity against Tumors Resistant to Cytotoxic T Cells
Authors: Ferrari de Andrade Lucas , Kumar Sushil , Luoma Adrienne M. , Ito Yoshinaga , Alves da Silva Pedro Henrique , Pan Deng , Pyrdol Jason W. , Yoon Charles H. , Wucherpfennig Kai W.
Published: April 2023

Abstract
Resistance to cytotoxic T cells is frequently mediated by loss of MHC class I expression or IFNγ signaling in tumor cells, such as mutations of B2M or JAK1 genes. Natural killer (NK) cells could potentially target such resistant tumors, but suitable NK-cell–based strategies remain to be developed. We hypothesized that such tumors could be targeted by NK cells if sufficient activating signals were provided. Human tumors frequently express the MICA and MICB ligands of the activating NKG2D receptor, but proteolytic shedding of MICA/B represents an important immune evasion mechanism in many human cancers. We showed that B2M- and JAK1-deficient metastases were targeted by NK cells following treatment with a mAb that blocks MICA/B shedding. We also demonstrated that the FDA-approved HDAC inhibitor panobinostat and a MICA/B antibody acted synergistically to enhance MICA/B surface expression on tumor cells. The HDAC inhibitor enhanced MICA/B gene expression, whereas the MICA/B antibody stabilized the synthesized protein on the cell surface. The combination of panobinostat and the MICA/B antibody reduced the number of pulmonary metastases formed by a human melanoma cell line in NOD/SCID gamma mice reconstituted with human NK cells. NK-cell–mediated immunity induced by a mAb specific for MICA/B, therefore, provides an opportunity to target tumors with mutations that render them resistant to cytotoxic T cells.
Data from Immunotargeting of the xCT Cystine/Glutamate Antiporter Potentiates the Efficacy of HER2-Targeted Immunotherapies in Breast Cancer
Authors: Conti Laura , Bolli Elisabetta , Di Lorenzo Antonino , Franceschi Valentina , Macchi Francesca , Riccardo Federica , Ruiu Roberto , Russo Luca , Quaglino Elena , Donofrio Gaetano , Cavallo Federica
Published: April 2023

Abstract
Despite HER2-targeted therapies improving the outcome of HER2+ breast cancer, many patients experience resistance and metastatic progression. Cancer stem cells (CSC) play a role in this resistance and progression, thus combining HER2 targeting with CSC inhibition could improve the management of HER2+ breast cancer. The cystine–glutamate antiporter, xCT, is overexpressed in mammary CSCs and is crucial for their redox balance, self-renewal, and resistance to therapies, representing a potential target for breast cancer immunotherapy. We developed a combined immunotherapy targeting HER2 and xCT using the Bovine Herpes virus-4 vector, a safe vaccine that can confer immunogenicity to tumor antigens. Mammary cancer–prone BALB-neuT mice, transgenic for rat Her2, were immunized with the single or combined vaccines. Anti-HER2 vaccination slowed primary tumor growth, whereas anti-xCT vaccination primarily prevented metastasis formation. The combination of the two vaccines exerted a complementary effect by mediating the induction of cytotoxic T cells and of HER2 and xCT antibodies that induce antibody-dependent cell-mediated cytotoxicity and hinder cancer cell proliferation. Antibodies targeting xCT, but not those targeting HER2, directly affected CSC viability, self-renewal, and migration, inducing the antimetastatic effect of xCT vaccination. Our findings present a new therapy for HER2+ breast cancer, demonstrating that CSC immunotargeting via anti-xCT vaccination synergizes with HER2-directed immunotherapy.
Data from CD8+ T–cell Immune Surveillance against a Tumor Antigen Encoded by the Oncogenic Long Noncoding RNA PVT1
Authors: Kikuchi Yasuhiro , Tokita Serina , Hirama Tomomi , Kochin Vitaly , Nakatsugawa Munehide , Shinkawa Tomoyo , Hirohashi Yoshihiko , Tsukahara Tomohide , Hata Fumitake , Takemasa Ichiro , Sato Noriyuki , Kanaseki Takayuki , Torigoe Toshihiko
Published: April 2023

Abstract
CD8+ T cells recognize peptides displayed by HLA class I molecules on cell surfaces, monitoring pathologic conditions such as cancer. Advances in proteogenomic analysis of HLA ligandomes have demonstrated that cells present a subset of cryptic peptides derived from noncoding regions of the genome; however, the roles of cryptic HLA ligands in tumor immunity remain unknown. In the current study, we comprehensively and quantitatively investigated the HLA class I ligandome of a set of human colorectal cancer and matched normal tissues, showing that cryptic translation products accounted for approximately 5% of the HLA class I ligandome. We also found that a peptide encoded by the long noncoding RNA (lncRNA) PVT1 was predominantly enriched in multiple colorectal cancer tissues. The PVT1 gene is located downstream of the MYC gene in the genome and is aberrantly overexpressed across a variety of cancers, reflecting its oncogenic property. The PVT1 peptide was recognized by patient CD8+ tumor-infiltrating lymphocytes, as well as peripheral blood mononuclear cells, suggesting the presence of patient immune surveillance. Our findings show that peptides can be translated from lncRNAs and presented by HLA class I and that cancer patient T cells are capable of sensing aberrations in noncoding regions of the genome.
Data from Overproduction of IFNγ by Cbl-b–Deficient CD8+ T Cells Provides Resistance against Regulatory T Cells and Induces Potent Antitumor Immunity
Authors: Han SeongJun , Liu Zhe Qi , Chung Douglas C. , Paul Michael St. , Garcia-Batres Carlos R. , Sayad Azin , Elford Alisha R. , Gold Matthew J. , Grimshaw Natasha , Ohashi Pamela S.
Published: April 2023

Abstract
Regulatory T cells (Treg) are an integral component of the adaptive immune system that negatively affect antitumor immunity. Here, we investigated the role of the E3 ubiquitin ligase casitas B-lineage lymphoma-b (Cbl-b) in establishing CD8+ T-cell resistance to Treg-mediated suppression to enhance antitumor immunity. Transcriptomic analyses suggested that Cbl-b regulates pathways associated with cytokine signaling and cellular proliferation. We showed that the hypersecretion of IFNγ by Cbl-b–deficient CD8+ T cells selectively attenuated CD8+ T-cell suppression by Tregs. Although IFNγ production by Cbl-b–deficient T cells contributed to phenotypic alterations in Tregs, the cytokine did not attenuate the suppressive function of Tregs. Instead, IFNγ had a profound effect on CD8+ T cells by directly upregulating interferon-stimulated genes and modulating T-cell activation. In murine models of adoptive T-cell therapy, Cbl-b–deficient T cells elicited superior antitumor immune response. Furthermore, Cbl-b–deficient CD8+ T cells were less susceptible to suppression by Tregs in the tumor through the effects of IFNγ. Collectively, this study demonstrates that the hypersecretion of IFNγ serves as a key mechanism by which Cbl-b–deficient CD8+ T cells are rendered resistant to Tregs.

See related Spotlight by Wolf and Baier, p. 370.
Data from T Cell–Mediated Targeted Delivery of Anti–PD-L1 Nanobody Overcomes Poor Antibody Penetration and Improves PD-L1 Blocking at the Tumor Site
Authors: Petit Pierre-Florent , Bombart Raphaële , Desimpel Pierre-Hubert , Naulaerts Stefan , Thouvenel Laurie , Collet Jean-François , Van den Eynde Benoit J. , Zhu Jingjing
Published: April 2023

Abstract
Monoclonal antibodies (mAbs) blocking immune checkpoints such as programmed death ligand 1 (PD-L1) have yielded strong clinical benefits in many cancer types. Still, the current limitations are the lack of clinical response in a majority of patients and the development of immune-related adverse events in some. As an alternative to PD-L1–specific antibody injection, we have developed an approach based on the engineering of tumor-targeting T cells to deliver intratumorally an anti–PD-L1 nanobody. In the MC38-OVA model, our strategy enhanced tumor control as compared with injection of PD-L1–specific antibody combined with adoptive transfer of tumor-targeting T cells. As a possible explanation for this, we demonstrated that PD-L1–specific antibody massively occupied PD-L1 in the periphery but failed to penetrate to PD-L1–expressing cells at the tumor site. In sharp contrast, locally delivered anti–PD-L1 nanobody improved PD-L1 blocking at the tumor site while avoiding systemic exposure. Our approach appears promising to overcome the limitations of immunotherapy based on PD-L1–specific antibodies.
Data from A Costimulatory CAR Improves TCR-based Cancer Immunotherapy
Authors: Omer Bilal , Cardenas Mara G. , Pfeiffer Thomas , Daum Rachel , Huynh Mai , Sharma Sandhya , Nouraee Nazila , Xie Cicilyn , Tat Candise , Perconti Silvana , Van Pelt Stacey , Scherer Lauren , DeRenzo Chris , Shum Thomas , Gottschalk Stephen , Arber Caroline , Rooney Cliona M.
Published: April 2023

Abstract
T-cell receptors (TCR) recognize intracellular and extracellular cancer antigens, allowing T cells to target many tumor antigens. To sustain proliferation and persistence, T cells require not only signaling through the TCR (signal 1), but also costimulatory (signal 2) and cytokine (signal 3) signaling. Because most cancer cells lack costimulatory molecules, TCR engagement at the tumor site results in incomplete T-cell activation and transient antitumor effects. To overcome this lack of signal 2, we genetically modified tumor-specific T cells with a costimulatory chimeric antigen receptor (CoCAR). Like classical CARs, CoCARs combine the antigen-binding domain of an antibody with costimulatory endodomains to trigger T-cell proliferation, but CoCARs lack the cytotoxic CD3ζ chain to avoid toxicity to normal tissues. We first tested a CD19-targeting CoCAR in combination with an HLA-A*02:01-restricted, survivin-specific transgenic TCR (sTCR) in serial cocultures with leukemia cells coexpressing the cognate peptide–HLA complex (signal 1) and CD19 (signal 2). The CoCAR enabled sTCR+ T cells to kill tumors over a median of four additional tumor challenges. CoCAR activity depended on CD19 but was maintained in tumors with heterogeneous CD19 expression. In a murine tumor model, sTCR+CoCAR+ T cells improved tumor control and prolonged survival compared with sTCR+ T cells. We further evaluated the CoCAR in Epstein–Barr virus–specific T cells (EBVST). CoCAR-expressing EBVSTs expanded more rapidly than nontransduced EBVSTs and delayed tumor progression in an EBV+ murine lymphoma model. Overall, we demonstrated that the CoCAR can increase the activity of T cells expressing both native and transgenic TCRs and enhance antitumor responses.
Data from Modified Manufacturing Process Modulates CD19CAR T-cell Engraftment Fitness and Leukemia-Free Survival in Pediatric and Young Adult Subjects
Authors: Ceppi Francesco , Wilson Ashley L. , Annesley Colleen , Kimmerly Gabriella R. , Summers Corinne , Brand Adam , Seidel Kristy , Wu Qian Vicky , Beebe Adam , Brown Christopher , Mgebroff Stephanie , Lindgren Catherine , Rawlings-Rhea Stephanie D. , Huang Wenjun , Pulsipher Michael A. , Wayne Alan S. , Park Julie R. , Jensen Michael C. , Gardner Rebecca A.
Published: April 2023

Abstract
T cells modified to express a chimeric antigen receptor (CAR) targeting CD19 can induce potent and sustained responses in children with relapsed/refractory acute lymphoblastic leukemia (ALL). The durability of remission is related to the length of time the CAR T cells persist. Efforts to understand differences in persistence have focused on the CAR construct, in particular the costimulatory signaling module of the chimeric receptor. We previously reported a robust intent-to-treat product manufacturing success rate and remission induction rate in children and young adults with recurrent/refractory B-ALL using the SCRI-CAR19v1 product, a second-generation CD19-specific CAR with 4-1BB costimulation coexpressed with the EGFRt cell-surface tag (NCT02028455). Following completion of the phase I study, two changes to CAR T-cell manufacturing were introduced: switching the T-cell activation reagent and omitting midculture EGFRt immunomagnetic selection. We tested the modified manufacturing process and resulting product, designated SCRI-CAR19v2, in a cohort of 21 subjects on the phase II arm of the trial. Here, we describe the unanticipated enhancement in product performance resulting in prolonged persistence and B-cell aplasia and improved leukemia-free survival with SCRI-CAR19v2 as compared with SCRI-CAR19v1.
Data from APOBEC Mutagenesis Inhibits Breast Cancer Growth through Induction of T cell–Mediated Antitumor Immune Responses
Authors: DiMarco Ashley V. , Qin Xiaodi , McKinney Brock J. , Garcia Nina Marie G. , Van Alsten Sarah C. , Mendes Elizabeth A. , Force Jeremy , Hanks Brent A. , Troester Melissa A. , Owzar Kouros , Xie Jichun , Alvarez James V.
Published: April 2023

Abstract
The APOBEC family of cytidine deaminases is one of the most common endogenous sources of mutations in human cancer. Genomic studies of tumors have found that APOBEC mutational signatures are enriched in the HER2 subtype of breast cancer and are associated with immunotherapy response in diverse cancer types. However, the direct consequences of APOBEC mutagenesis on the tumor immune microenvironment have not been thoroughly investigated. To address this, we developed syngeneic murine mammary tumor models with inducible expression of APOBEC3B. We found that APOBEC activity induced antitumor adaptive immune responses and CD4+ T cell–mediated, antigen-specific tumor growth inhibition. Although polyclonal APOBEC tumors had a moderate growth defect, clonal APOBEC tumors were almost completely rejected, suggesting that APOBEC-mediated genetic heterogeneity limits antitumor adaptive immune responses. Consistent with the observed immune infiltration in APOBEC tumors, APOBEC activity sensitized HER2-driven breast tumors to anti–CTLA-4 checkpoint inhibition and led to a complete response to combination anti–CTLA-4 and anti-HER2 therapy. In human breast cancers, the relationship between APOBEC mutagenesis and immunogenicity varied by breast cancer subtype and the frequency of subclonal mutations. This work provides a mechanistic basis for the sensitivity of APOBEC tumors to checkpoint inhibitors and suggests a rationale for using APOBEC mutational signatures and clonality as biomarkers predicting immunotherapy response in HER2-positive (HER2+) breast cancers.