bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from A Rapid Embryonic Stem Cell–Based Mouse Model for B-cell Lymphomas Driven by Epstein–Barr Virus Protein LMP1
Authors: Ba Zhaoqing , Meng Fei-Long , Gostissa Monica , Huang Pei-Yi , Ke Qiang , Wang Zhe , Dao Mai N. , Fujiwara Yuko , Rajewsky Klaus , Zhang Baochun , Alt Frederick W.
Published: April 2023

Abstract
The Epstein–Barr virus (EBV) latent membrane protein 1 (LMP1) contributes to oncogenic human B-cell transformation. Mouse B cells conditionally expressing LMP1 are not predisposed to B-cell malignancies, as LMP1-expressing B cells are eliminated by T cells. However, mice with conditional B-cell LMP1 expression and genetic elimination of α/β and γ/δ T cells (“CLT” mice) die early in association with B-cell lymphoproliferation and lymphomagenesis. Generation of CLT mice involves in-breeding multiple independently segregating alleles. Thus, although introduction of additional activating or knockout mutations into the CLT model is desirable for further B-cell expansion and immunosurveillance studies, doing such experiments by germline breeding is time-consuming, expensive, and sometimes unfeasible. To generate a more tractable model, we generated clonal CLT embryonic stem (ES) cells from CLT embryos and injected them into RAG2-deficient blastocysts to generate chimeric mice, which, like germline CLT mice, harbor splenic CLT B cells and lack T cells. CLT chimeric mice generated by this RAG2-deficient blastocyst complementation (“RDBC”) approach die rapidly in association with B-cell lymphoproliferation and lymphoma. Because CLT lymphomas routinely express the activation-induced cytidine deaminase (AID) antibody diversifier, we tested potential AID roles by eliminating the AID gene in CLT ES cells and testing them via RDBC. We found that CLT and AID-deficient CLT ES chimeras had indistinguishable phenotypes, showing that AID is not essential for LMP1-induced lymphomagenesis. Beyond expanding accessibility and utility of CLT mice as a cancer immunotherapy model, our studies provide a new approach for facilitating generation of genetically complex mouse cancer models. Cancer Immunol Res; 3(6); 641–9. ©2015 AACR.
Data from Farnesoid X Receptor Constructs an Immunosuppressive Microenvironment and Sensitizes FXRhighPD-L1low NSCLC to Anti–PD-1 Immunotherapy
Authors: You Wenjie , Li Lijun , Sun Deqiao , Liu Xueqing , Xia Zongjun , Xue Shan , Chen Bi , Qin Hui , Ai Jing , Jiang Handong
Published: April 2023

Abstract
The farnesoid X receptor (FXR) regulates inflammation and immune responses in a subset of immune-mediated diseases. We previously reported that FXR expression promotes tumor cell proliferation in non–small cell lung cancer (NSCLC). Here we study the relevance of FXR to the immune microenvironment of NSCLC. We found an inverse correlation between FXR and PD-L1 expression in a cohort of 408 NSCLC specimens; from this, we identified a subgroup of FXRhighPD-L1low patients. We showed that FXR downregulates PD-L1 via transrepression and other mechanisms in NSCLC. Cocultured with FXRhighPD-L1low NSCLC cell lines, effector function and proliferation of CD8+ T cell in vitro are repressed. We also detected downregulation of PD-L1 in FXR-overexpressing Lewis lung carcinoma (LLC) mouse syngeneic models, indicating an FXRhighPD-L1low subtype in which FXR suppresses tumor-infiltrating immune cells. Anti–PD-1 therapy was effective against FXRhighPD-L1low mouse LLC tumors. Altogether, our findings demonstrate an immunosuppressive role for FXR in the FXRhighPD-L1low NSCLC subtype and provide translational insights into therapeutic response in PD-L1low NSCLC patients treated with anti–PD-1. We recommend FXRhighPD-L1low as a biomarker to predict responsiveness to anti–PD-1 immunotherapy.
Data from Whole Exome and Transcriptome Analyses Integrated with Microenvironmental Immune Signatures of Lung Squamous Cell Carcinoma
Authors: Seo Jeong-Sun , Lee Ji Won , Kim Ahreum , Shin Jong-Yeon , Jung Yoo Jin , Lee Sae Bom , Kim Yoon Ho , Park Samina , Lee Hyun Joo , Park In-Kyu , Kang Chang-Hyun , Yun Ji-Young , Kim Jihye , Kim Young Tae
Published: April 2023

Abstract
The immune microenvironment in lung squamous cell carcinoma (LUSC) is not well understood, with interactions between the host immune system and the tumor, as well as the molecular pathogenesis of LUSC, awaiting better characterization. To date, no molecularly targeted agents have been developed for LUSC treatment. Identification of predictive and prognostic biomarkers for LUSC could help optimize therapy decisions. We sequenced whole exomes and RNA from 101 tumors and matched noncancer control Korean samples. We used the information to predict subtype-specific interactions within the LUSC microenvironment and to connect genomic alterations with immune signatures. Hierarchical clustering based on gene expression and mutational profiling revealed subtypes that were either immune defective or immune competent. We analyzed infiltrating stromal and immune cells to further characterize the tumor microenvironment. Elevated expression of macrophage 2 signature genes in the immune competent subtype confirmed that tumor-associated macrophages (TAM) linked inflammation and mutation-driven cancer. A negative correlation was evident between the immune score and the amount of somatic copy-number variation (SCNV) of immune genes (r = −0.58). The SCNVs showed a potential detrimental effect on immunity in the immune-deficient subtype. Knowledge of the genomic alterations in the tumor microenvironment could be used to guide design of immunotherapy options that are appropriate for patients with certain cancer subtypes. Cancer Immunol Res; 6(7); 848–59. ©2018 AACR.
Data from Selective Targeting of Glioblastoma with EGFRvIII/EGFR Bitargeted Chimeric Antigen Receptor T Cell
Authors: Jiang Hua , Gao Huiping , Kong Juan , Song Bo , Wang Peng , Shi Bizhi , Wang Huamao , Li Zonghai
Published: April 2023

Abstract
The heterogeneous expression of EGFRvIII [variant III mutant of epidermal growth factor receptor (EGFR)] in glioblastoma has significant impact on the clinical response to the treatment of EGFRvIII-specific chimeric antigen receptor–engineered T (CAR T) cells. We hypothesized that CAR T cells that could target both EGFRvIII and the form of EGFR expressed on tumor cells, but not EGFR on normal cells, would greatly improve efficacy without inducing on-target, off-tumor toxicity. Therefore, we developed a humanized single-chain antibody, M27, with a single specificity that binds to an epitope found both on wild-type EGFR- and EGFRvIII-overexpressing tumor cells, but not EGFR-expressing normal cells, including primary keratinocytes, on which wild-type EGFR is highly expressed. M27-derived CAR T cells effectively lysed EGFRvIII- or EGFR-overexpressing tumor cells, but showed no observable toxicity on normal cells. Inclusion of the CD137 (4-1BB) costimulatory intracellular domain in the M27-28BBZ CAR provided CAR T cells with higher tumor lysis activity than when not included (as in the M27-28Z CAR). The growth of established EGFR- or EGFRvIII-overexpressing glioma xenografts was suppressed by M27-28BBZ CAR T cells as well. The growth of heterogeneic xenograft tumors, created by mixing EGFR- and EGFR-overexpressing glioblastoma cells, was also effectively inhibited by M27-28BBZ CAR T cells. The survival of mice in the orthotopic models was significantly prolonged after M27-28BBZ CAR T-cell infusion. These results suggested that tumor-selective, bitargeted anti-EGFR/EGFRvIII CAR T cells may be a promising modality for the treatment of patients with EGFR/EGFRvIII-overexpressing glioblastoma. Cancer Immunol Res; 6(11); 1314–26. ©2018 AACR.
Data from LIN28/let-7/PD-L1 Pathway as a Target for Cancer Immunotherapy
Authors: Chen Yanlian , Xie Chen , Zheng Xiaohui , Nie Xin , Wang Zining , Liu Haiying , Zhao Yong
Published: April 2023

Abstract
The immunocheckpoint protein PD-1/PD-L1 is considered a promising target for cancer immunotherapeutics. However, the objective response rate using antibodies that block the interaction between PD-1 and PD-L1 was less than 40%, and the mechanism underlying regulation of PD-1/PD-L1 expression is poorly understood. In this study, we identified the miRNA let-7 that posttranscriptionally suppresses PD-L1 expression. LIN28, an RNA binding protein upregulated in most cancer cells, inhibits the biogenesis of let-7, thus promoting PD-L1 expression. Therefore, inhibition of LIN28 may be a strategy to prevent immune evasion of cancer cells. We found that treatment with a LIN28 inhibitor, the small compound C1632, increases let-7 and suppresses PD-L1 expression, leading to reactivation of antitumor immunity in vitro and in vivo. In addition, C1632 also displayed the capacity to inhibit cancer cell proliferation and tumor growth in mice. Altogether, these findings identified LIN28/let-7 as a target for PD-L1–mediated immunotherapeutics and reveal the potential of C1632 and its derivatives as promising oncotherapeutic agents.
Data from Quantitative Analysis of Immune Infiltrates in Primary Melanoma
Authors: Gartrell Robyn D. , Marks Douglas K. , Hart Thomas D. , Li Gen , Davari Danielle R. , Wu Alan , Blake Zoë , Lu Yan , Askin Kayleigh N. , Monod Anthea , Esancy Camden L. , Stack Edward C. , Jia Dan Tong , Armenta Paul M. , Fu Yichun , Izaki Daisuke , Taback Bret , Rabadan Raul , Kaufman Howard L. , Drake Charles G. , Horst Basil A. , Saenger Yvonne M.
Published: April 2023

Abstract
Novel methods to analyze the tumor microenvironment (TME) are urgently needed to stratify melanoma patients for adjuvant immunotherapy. Tumor-infiltrating lymphocyte (TIL) analysis, by conventional pathologic methods, is predictive but is insufficiently precise for clinical application. Quantitative multiplex immunofluorescence (qmIF) allows for evaluation of the TME using multiparameter phenotyping, tissue segmentation, and quantitative spatial analysis (qSA). Given that CD3+CD8+ cytotoxic lymphocytes (CTLs) promote antitumor immunity, whereas CD68+ macrophages impair immunity, we hypothesized that quantification and spatial analysis of macrophages and CTLs would correlate with clinical outcome. We applied qmIF to 104 primary stage II to III melanoma tumors and found that CTLs were closer in proximity to activated (CD68+HLA-DR+) macrophages than nonactivated (CD68+HLA-DR−) macrophages (P < 0.0001). CTLs were further in proximity from proliferating SOX10+ melanoma cells than nonproliferating ones (P < 0.0001). In 64 patients with known cause of death, we found that high CTL and low macrophage density in the stroma (P = 0.0038 and P = 0.0006, respectively) correlated with disease-specific survival (DSS), but the correlation was less significant for CTL and macrophage density in the tumor (P = 0.0147 and P = 0.0426, respectively). DSS correlation was strongest for stromal HLA-DR+ CTLs (P = 0.0005). CTL distance to HLA-DR− macrophages associated with poor DSS (P = 0.0016), whereas distance to Ki67− tumor cells associated inversely with DSS (P = 0.0006). A low CTL/macrophage ratio in the stroma conferred a hazard ratio (HR) of 3.719 for death from melanoma and correlated with shortened overall survival (OS) in the complete 104 patient cohort by Cox analysis (P = 0.009) and merits further development as a biomarker for clinical application. Cancer Immunol Res; 6(4); 481–93. ©2018 AACR.
Data from Targeting Tissue Factor for Immunotherapy of Triple-Negative Breast Cancer Using a Second-Generation ICON
Authors: Hu Zhiwei , Shen Rulong , Campbell Amanda , McMichael Elizabeth , Yu Lianbo , Ramaswamy Bhuvaneswari , London Cheryl A. , Xu Tian , Carson William E.
Published: April 2023

Abstract
Triple-negative breast cancer (TNBC) is a leading cause of breast cancer death and is often associated with BRCA1 and BRCA2 mutation. Due to the lack of validated target molecules, no targeted therapy for TNBC is approved. Tissue factor (TF) is a common yet specific surface target receptor for cancer cells, tumor vascular endothelial cells, and cancer stem cells in several types of solid cancers, including breast cancer. Here, we report evidence supporting the idea that TF is a surface target in TNBC. We used in vitro cancer lines and in vivo tumor xenografts in mice, all with BRCA1 or BRCA2 mutations, derived from patients' tumors. We showed that TF is overexpressed on TNBC cells and tumor neovasculature in 50% to 85% of TNBC patients (n = 161) and in TNBC cell line–derived xenografts (CDX) and patient-derived xenografts (PDX) from mice, but was not detected in adjacent normal breast tissue. We then describe the development of a second-generation TF-targeting immunoconjugate (called L-ICON1, for lighter or light chain ICON) with improved efficacy and safety profiles compared with the original ICON. We showed that L-ICON1 kills TNBC cells in vitro via antibody-dependent cell-mediated cytotoxicity and can be used to treat human and murine TNBC CDX as well as PDX in vivo in orthotopic mouse models. Thus, TF could be a useful target for the development of immunotherapeutics for TNBC patients, with or without BRCA1 and BRCA2 mutations. Cancer Immunol Res; 6(6); 671–84. ©2018 AACR.
Data from Anti–CTLA-4 Activates Intratumoral NK Cells and Combined with IL15/IL15Rα Complexes Enhances Tumor Control
Authors: Sanseviero Emilio , O’Brien Erin M. , Karras Jenna R. , Shabaneh Tamer B. , Aksoy Bulent Arman , Xu Wei , Zheng Cathy , Yin Xiangfan , Xu Xiaowei , Karakousis Giorgos C. , Amaravadi Ravi K. , Nam Brian , Turk Mary Jo , Hammerbacher Jeff , Rubinstein Mark P. , Schuchter Lynn M. , Mitchell Tara C. , Liu Qin , Stone Erica L.
Published: April 2023

Abstract
Antibodies targeting CTLA-4 induce durable responses in some patients with melanoma and are being tested in a variety of human cancers. However, these therapies are ineffective for a majority of patients across tumor types. Further understanding the immune alterations induced by these therapies may enable the development of novel strategies to enhance tumor control and biomarkers to identify patients most likely to respond. In several murine models, including colon26, MC38, CT26, and B16 tumors cotreated with GVAX, anti–CTLA-4 efficacy depends on interactions between the Fc region of CTLA-4 antibodies and Fc receptors (FcR). Anti–CTLA-4 binding to FcRs has been linked to depletion of intratumoral T regulatory cells (Treg). In agreement with previous studies, we found that Tregs infiltrating CT26, B16-F1, and autochthonous BrafV600EPten−/− melanoma tumors had higher expression of surface CTLA-4 (sCTLA-4) than other T-cell subsets, and anti–CTLA-4 treatment led to FcR-dependent depletion of Tregs infiltrating CT26 tumors. This Treg depletion coincided with activation and degranulation of intratumoral natural killer cells. Similarly, in non–small cell lung cancer (NSCLC) and melanoma patient-derived tumor tissue, Tregs had higher sCTLA-4 expression than other intratumoral T-cell subsets, and Tregs infiltrating NSCLC expressed more sCTLA-4 than circulating Tregs. Patients with cutaneous melanoma who benefited from ipilimumab, a mAb targeting CTLA-4, had higher intratumoral CD56 expression, compared with patients who received little to no benefit from this therapy. Furthermore, using the murine CT26 model we found that combination therapy with anti–CTLA-4 plus IL15/IL15Rα complexes enhanced tumor control compared with either monotherapy.
Data from Lnc-C/EBPβ Negatively Regulates the Suppressive Function of Myeloid-Derived Suppressor Cells
Authors: Gao Yunhuan , Sun Wei , Shang Wencong , Li Yuanyuan , Zhang Dan , Wang Tianze , Zhang Xipeng , Zhang Shiwu , Zhang Yuan , Yang Rongcun
Published: April 2023

Abstract
Myeloid-derived suppressor cells (MDSC) are regulators of immune responses in cancer. The differentiation and function of these MDSCs may be regulated through multiple factors, such as microRNAs. However, the effect of long noncoding RNAs (lncRNA) on the differentiation and function of MDSCs is poorly understood. We identified a long noncoding RNA (lncRNA) named lnc-C/EBPβ in MDSCs, which may control suppressive functions of MDSCs. Lnc-C/EBPβ could be induced in in vitro and in vivo tumor and inflammatory environments. It regulated a set of target transcripts, such as Arg-1, NOS2, NOX2, and COX2, to control immune-suppressive function and differentiation of MDSCs. This lncRNA was also able to bind to the C/EBPβ isoform LIP to inhibit the activation of C/EBPβ. We also found that the conserved homologue lnc-C/EBPβ has a similar function to murine lnc-C/EBPβ. These findings suggest a negative feedback role for lnc-C/EBPβ in controlling the immunosuppressive functions of MDSC in the tumor environment. Cancer Immunol Res; 6(11); 1352–63. ©2018 AACR.
Data from Stromal Fibroblasts Mediate Anti–PD-1 Resistance via MMP-9 and Dictate TGFβ Inhibitor Sequencing in Melanoma
Authors: Zhao Fei , Evans Kathy , Xiao Christine , DeVito Nicholas , Theivanthiran Balamayooran , Holtzhausen Alisha , Siska Peter J. , Blobe Gerard C. , Hanks Brent A.
Published: April 2023

Abstract
Although anti–PD-1 therapy has improved clinical outcomes for select patients with advanced cancer, many patients exhibit either primary or adaptive resistance to checkpoint inhibitor immunotherapy. The role of the tumor stroma in the development of these mechanisms of resistance to checkpoint inhibitors remains unclear. We demonstrated that pharmacologic inhibition of the TGFβ signaling pathway synergistically enhanced the efficacy of anti–CTLA-4 immunotherapy but failed to augment anti–PD-1/PD-L1 responses in an autochthonous model of BRAFV600E melanoma. Additional mechanistic studies revealed that TGFβ pathway inhibition promoted the proliferative expansion of stromal fibroblasts, thereby facilitating MMP-9–dependent cleavage of PD-L1 surface expression, leading to anti–PD-1 resistance in this model. Further work demonstrated that melanomas escaping anti–PD-1 therapy exhibited a mesenchymal phenotype associated with enhanced TGFβ signaling activity. Delayed TGFβ inhibitor therapy, following anti–PD-1 escape, better served to control further disease progression and was superior to a continuous combination of anti–PD-1 and TGFβ inhibition. This work illustrates that formulating immunotherapy combination regimens to enhance the efficacy of checkpoint blockade requires an in-depth understanding of the impact of these agents on the tumor microenvironment. These data indicated that stromal fibroblast MMP-9 may desensitize tumors to anti–PD-1 and suggests that TGFβ inhibition may generate greater immunologic efficacy when administered following the development of acquired anti–PD-1 resistance.

See related Spotlight on p. 1444
Data from Converting Lymphoma Cells into Potent Antigen-Presenting Cells for Interferon-Induced Tumor Regression
Authors: Liao Jing , Luan Yan , Ren Zhenhua , Liu Xiaojuan , Xue Diyuan , Xu Hairong , Sun Zhichen , Yang Kaiting , Peng Hua , Fu Yang-Xin
Published: April 2023

Abstract
Anti-hCD20 is a therapeutic mAb that is clinically used to treat B-cell lymphoma. Some lymphomas are resistant to anti-hCD20; others relapse after treatment with anti-hCD20. Using a syngeneic immunocompetent mouse model, we observed that targeting lymphoma with interferon-α (IFNα) abolished resistance of B-cell lymphoma to anti-CD20 while limiting interferon (IFN)-associated systemic toxicity in the host. Control of tumors by a fusion of anti-CD20 and IFNα (anti–CD20-IFNα) depended on existing tumor-infiltrating CD8+ T cells. Although lymphomas were resistant to IFN-directed killing, IFN-exposed tumor cells became the dominant antigen-presenting cells (APC) for the reactivation of tumor-infiltrating CD8+ T cells that then controlled those lymphomas. Anti–CD20-IFNα also abolished checkpoint blockade resistance in advanced B-cell lymphoma. Our findings indicate that anti–CD20-IFNα eradicates B-cell lymphoma by employing tumor cells as APCs to reactivate tumor-infiltrating CD8+ T cells and synergizing with anti–PD-L1 treatment. Cancer Immunol Res; 5(7); 560–70. ©2017 AACR.
Data from Exosomes Released from Tumor-Associated Macrophages Transfer miRNAs That Induce a Treg/Th17 Cell Imbalance in Epithelial Ovarian Cancer
Authors: Zhou Jieru , Li Xiaoduan , Wu Xiaoli , Zhang Ting , Zhu Qinyi , Wang Xinjing , Wang Husheng , Wang Kai , Lin Yingying , Wang Xipeng
Published: April 2023

Abstract
The immune microenvironment is crucial for epithelial ovarian cancer (EOC) progression and consists of tumor-associated macrophages (TAM) and T lymphocytes, such as regulatory T cells (Treg) and T helper 17 (Th17) cells. In this study, the Treg/Th17 ratio was significantly higher in EOC in situ and in metastatic peritoneal tissues than in benign ovarian tumors and benign peritoneum. The Treg/Th17 ratio was associated with histologic grade and was an independent prognostic factor for overall survival of EOC patients. On the basis of microarray analysis of exosomes derived from TAMs, we identified miRNAs enriched in the exosomes, including miR-29a-3p and miR-21-5p. When the two miRNA mimics were transfected into CD4+ T cells, they directly suppressed STAT3 and regulated Treg/Th17 cells, inducing an imbalance, and they had a synergistic effect on STAT3 inhibition. Taken together, these results indicate that exosomes mediate the interaction between TAMs and T cells, generating an immune-suppressive microenvironment that facilitates EOC progression and metastasis. These findings suggest that targeting these exosomes or their associated miRNAs might pave the way for the development of novel treatments for EOC.
Data from Intracellular Activation of Complement C3 Leads to PD-L1 Antibody Treatment Resistance by Modulating Tumor-Associated Macrophages
Authors: Zha Haoran , Wang Xinxin , Zhu Ying , Chen Diangang , Han Xiao , Yang Fei , Gao Jianbao , Hu Chunyan , Shu Chi , Feng Yi , Tan Yulong , Zhang Jinyu , Li Yongsheng , Wan Yisong Y. , Guo Bo , Zhu Bo
Published: April 2023

Abstract
Complement aids in the construction of an immunosuppressive tumor microenvironment. Tumor cell–derived C3 has been previously reported, but whether and how it acts on antitumor immunity remains to be elucidated. Here, we describe a mechanism for tumor cell–derived C3 in suppressing antitumor immunity. Tumor cell–derived C3 was activated intracellularly, which results in generation of C3a. C3a modulated tumor-associated macrophages via C3a-C3aR-PI3Kγ signaling, thereby repressing antitumor immunity. Deletion of C3 in tumor cells that had high C3 expression enhanced efficacy of anti–PD-L1 treatment. Collectively, our results suggest tumor cell–derived C3 may be a useful target for cancer immunotherapy and that targeting C3 in tumor cells may enhance antitumor immunity.
Data from Myeloid-Derived Suppressive Cells Promote B cell–Mediated Immunosuppression via Transfer of PD-L1 in Glioblastoma
Authors: Lee-Chang Catalina , Rashidi Aida , Miska Jason , Zhang Peng , Pituch Katarzyna C. , Hou David , Xiao Ting , Fischietti Mariafausta , Kang Seong Jae , Appin Christina L. , Horbinski Craig , Platanias Leonidas C. , Lopez-Rosas Aurora , Han Yu , Balyasnikova Irina V. , Lesniak Maciej S.
Published: April 2023

Abstract
The potent immunosuppression induced by glioblastoma (GBM) is one of the primary obstacles to finding effective immunotherapies. One hallmark of the GBM-associated immunosuppressive landscape is the massive infiltration of myeloid-derived suppressor cells (MDSC) and, to a lesser extent, regulatory T cells (Treg) within the tumor microenvironment. Here, we showed that regulatory B cells (Breg) are a prominent feature of the GBM microenvironment in both preclinical models and clinical samples. Forty percent of GBM patients (n = 60) scored positive for B-cell tumor infiltration. Human and mouse GBM-associated Bregs were characterized by immunosuppressive activity toward activated CD8+ T cells, the overexpression of inhibitory molecules PD-L1 and CD155, and production of immunosuppressive cytokines TGFβ and IL10. Local delivery of B cell–depleting anti-CD20 immunotherapy improved overall survival of animals (IgG vs. anti-CD20 mean survival: 18.5 vs. 33 days, P = 0.0001), suggesting a potential role of Bregs in GBM progression. We unveiled that GBM-associated MDSCs promoted regulatory B-cell function by delivering microvesicles transporting membrane-bound PD-L1, able to be up-taken by tumoral B cells. The transfer of functional PD-L1 via microvesicles conferred Bregs the potential to suppress CD8+ T-cell activation and acquisition of an effector phenotype. This work uncovered the role of B cells in GBM physiopathology and provides a mechanism by which the GBM microenvironment controls B cell–mediated immunosuppression.

See related Spotlight on p. 1902
Data from Targeting the YB-1/PD-L1 Axis to Enhance Chemotherapy and Antitumor Immunity
Authors: Tao Zhen , Ruan Hailong , Sun Lin , Kuang Dong , Song Yongchun , Wang Qi , Wang Tao , Hao Yi , Chen Ke
Published: April 2023

Abstract
Tumor cells can escape immune destruction in tumor chemoresistance, but the mechanism for this phenomenon remains unclear. Y-box binding protein 1 (YB-1), which is upregulated in chemoresistant tumor cells, plays a role in the acquisition of multidrug resistance. Here, we demonstrate that chemotherapy induced an immunosuppressive microenvironment in the tumor and induced immune evasion through YB-1–mediated programmed death-1 ligand 1 (PD-L1) upregulation. Examination of the YB-1 protein and mRNA showed an increase in YB-1 expression in hepatocellular carcinoma (HCC). High YB-1 expression negatively correlated with the overall survival of HCC patients. YB-1 expression positively correlated with PD-L1, and YB-1 induced PD-L1 expression by binding a PD-L1 promoter motif. YB-1 expression was upregulated in chemoresistant HCC cells, and YB-1 knockdown reversed chemoresistance via T-cell activation in the tumor microenvironment due to blocked PD-L1 expression. We also found that inhibition of the tumor immunosuppressive environment and immune evasion was accompanied by proliferation of functional cytotoxic CD8+ T cells and inhibition of myeloid-derived suppressor cells and regulatory T cells in the tumor environment. Our data indicate that targeting the YB-1 signaling axis, which simultaneously reverses both tumor immune evasion and multidrug resistance, may improve the antitumor response. This finding suggests a treatment modality against tumor chemoresistance.
Data from Lactate-Modulated Immunosuppression of Myeloid-Derived Suppressor Cells Contributes to the Radioresistance of Pancreatic Cancer
Authors: Yang Xuguang , Lu Yun , Hang Junjie , Zhang Junfeng , Zhang Tiening , Huo Yanmiao , Liu Jun , Lai Songtao , Luo Dawei , Wang Liwei , Hua Rong , Lin Yuli
Published: April 2023

Abstract
The mechanisms responsible for radioresistance in pancreatic cancer have yet to be elucidated, and the suppressive tumor immune microenvironment must be considered. We investigated whether the radiotherapy-augmented Warburg effect helped myeloid cells acquire an immunosuppressive phenotype, resulting in limited treatment efficacy of pancreatic ductal adenocarcinoma (PDAC). Radiotherapy enhanced the tumor-promoting activity of myeloid-derived suppressor cells (MDSC) in pancreatic cancer. Sustained increase in lactate secretion, resulting from the radiation-augmented Warburg effect, was responsible for the enhanced immunosuppressive phenotype of MDSCs after radiotherapy. Hypoxia-inducible factor-1α (HIF-1α) was essential for tumor cell metabolism and lactate-regulated activation of MDSCs via the G protein-coupled receptor 81 (GPR81)/mTOR/HIF-1α/STAT3 pathway. Blocking lactate production in tumor cells or deleting Hif-1α in MDSCs reverted antitumor T-cell responses and effectively inhibited tumor progression after radiotherapy in pancreatic cancer. Our investigation highlighted the importance of radiation-induced lactate in regulating the inhibitory immune microenvironment of PDAC. Targeting lactate derived from tumor cells and the HIF-1α signaling in MDSCs may hold distinct promise for clinical therapies to alleviate radioresistance in PDAC.
Data from Spliced Peptides and Cytokine-Driven Changes in the Immunopeptidome of Melanoma
Authors: Faridi Pouya , Woods Katherine , Ostrouska Simone , Deceneux Cyril , Aranha Ritchlynn , Duscharla Divya , Wong Stephen Q. , Chen Weisan , Ramarathinam Sri H. , Lim Kam Sian Terry C.C. , Croft Nathan P. , Li Chen , Ayala Rochelle , Cebon Jonathan S. , Purcell Anthony W. , Schittenhelm Ralf B. , Behren Andreas
Published: April 2023

Abstract
Antigen recognition by CD8+ T cells is governed by the pool of peptide antigens presented on the cell surface in the context of HLA class I complexes. Studies have shown not only a high degree of plasticity in the immunopeptidome, but also that a considerable fraction of all presented peptides is generated through proteasome-mediated splicing of noncontiguous regions of proteins to form novel peptide antigens. Here, we used high-resolution mass spectrometry combined with new bioinformatic approaches to characterize the immunopeptidome of melanoma cells in the presence or absence of IFNγ. In total, we identified more than 60,000 peptides from a single patient-derived cell line (LM-MEL-44) and demonstrated that IFNγ induced changes in the peptidome, with an overlap of only approximately 50% between basal and treated cells. Around 6% to 8% of the peptides were identified as cis-spliced peptides, and 2,213 peptides (1,827 linear and 386 cis-spliced peptides) were derived from known melanoma-associated antigens. These peptide antigens were equally distributed between the constitutive- and IFNγ-induced peptidome. We next examined additional HLA-matched patient-derived cell lines to investigate how frequently these peptides were identified and found that a high proportion of both linear and spliced peptides was conserved between individual patient tumors, drawing on data amassing to more than 100,000 peptide sequences. Several of these peptides showed in vitro immunogenicity across multiple patients with melanoma. These observations highlight the breadth and complexity of the repertoire of immunogenic peptides that can be exploited therapeutically and suggest that spliced peptides are a major class of tumor antigens.
Data from Bispecific Targeting of PD-1 and PD-L1 Enhances T-cell Activation and Antitumor Immunity
Authors: Kotanides Helen , Li Yiwen , Malabunga Maria , Carpenito Carmine , Eastman Scott W. , Shen Yang , Wang George , Inigo Ivan , Surguladze David , Pennello Anthony L. , Persaud Krishnadatt , Hindi Sagit , Topper Michael , Chen Xinlei , Zhang Yiwei , Bulaon Danielle K. , Bailey Tim , Lao Yanbin , Han Bing , Torgerson Stacy , Chin Darin , Sonyi Andreas , Haidar Jaafar N. , Novosiadly Ruslan D. , Moxham Christopher M. , Plowman Gregory D. , Ludwig Dale L. , Kalos Michael
Published: April 2023

Abstract
The programmed cell death protein 1 receptor (PD-1) and programmed death ligand 1 (PD-L1) coinhibitory pathway suppresses T-cell–mediated immunity. We hypothesized that cotargeting of PD-1 and PD-L1 with a bispecific antibody molecule could provide an alternative therapeutic approach, with enhanced antitumor activity, compared with monospecific PD-1 and PD-L1 antibodies. Here, we describe LY3434172, a bispecific IgG1 mAb with ablated Fc immune effector function that targets both human PD-1 and PD-L1. LY3434172 fully inhibited the major inhibitory receptor–ligand interactions in the PD-1 pathway. LY3434172 enhanced functional activation of T cells in vitro compared with the parent anti–PD-1 and anti–PD-L1 antibody combination or respective monotherapies. In mouse tumor models reconstituted with human immune cells, LY3434172 therapy induced dramatic and potent antitumor activity compared with each parent antibody or their combination. Collectively, these results demonstrated the enhanced immunomodulatory (immune blockade) properties of LY3434172, which improved antitumor immune response in preclinical studies, thus supporting its evaluation as a novel bispecific cancer immunotherapy.
Data from Long Noncoding RNAs Control the Modulation of Immune Checkpoint Molecules in Cancer
Authors: Xu Shouping , Wang Qin , Kang Yujuan , Liu Jiena , Yin Yanling , Liu Lei , Wu Hao , Li Siwei , Sui Shiyao , Shen Meiying , Zheng Wei , Pang Da
Published: April 2023

Abstract
Long noncoding RNAs (lncRNA) that are associated with immune checkpoints have not been identified, and the mechanism by which such lncRNAs might regulate the expression of immune checkpoints is unknown in human cancer. Immune checkpoint–associated lncRNAs (ICP-lncRNA) were identified and validated via a comprehensive bioinformatic analysis of The Cancer Genome Atlas data. These ICP-lncRNAs were involved in key immune response and immune cell receptor signaling pathways. The expression of ICP-lncRNAs was upregulated and correlated with a poor prognosis in patients with cancer. HLA complex P5 (HCP5) and myocardial infarction associated transcript (MIAT) promoted tumor growth and upregulated the expression of PD-L1/CD274 via a competing endogenous RNA mechanism of sponging miR-150-5p. The combination of MIAT knockdown and PD-L1 antibody administration showed a synergistic inhibitory effect on tumor growth. Finally, the expression of both HCP5 and MIAT was confirmed to be transcriptionally suppressed by CCCTC-binding factor (CTCF), and lipopolysaccharide induced CTCF eviction from the HCP5 and MIAT promoters, attenuating the transcriptionally suppressive activity of CTCF. This study enlarges the functional landscape of known lncRNAs in human cancer and indicates novel insights into their roles in the field of tumor immunity and immunotherapy. These findings may aid in the comprehensive management of human cancer with immunotherapy.
Data from A Machine Learning Approach Yields a Multiparameter Prognostic Marker in Liver Cancer
Authors: Liu Xiaoli , Lu Jilin , Zhang Guanxiong , Han Junyan , Zhou Wei , Chen Huan , Zhang Henghui , Yang Zhiyun
Published: April 2023

Abstract
A number of staging systems have been developed to predict clinical outcomes in hepatocellular carcinoma (HCC). However, no general consensus has been reached regarding the optimal model. New approaches such as machine learning (ML) strategies are powerful tools for incorporating risk factors from multiple platforms. We retrospectively reviewed the baseline information, including clinicopathologic characteristics, laboratory parameters, and peripheral immune features reflecting T-cell function, from three HCC cohorts. A gradient-boosting survival (GBS) classifier was trained with prognosis-related variables in the training dataset and validated in two independent cohorts. We constructed a 20-feature GBS model classifier incorporating one clinical feature, 14 laboratory parameters, and five T-cell function parameters obtained from peripheral blood mononuclear cells. The GBS model–derived risk scores demonstrated high concordance indexes (C-indexes): 0.844, 0.827, and 0.806 in the training set and validation sets 1 and 2, respectively. The GBS classifier could separate patients into high-, medium- and low-risk subgroups with respect to death in all datasets (P < 0.05 for all comparisons). A higher risk score was positively correlated with a higher clinical stage and the presence of portal vein tumor thrombus (PVTT). Subgroup analyses with respect to Child–Pugh class, Barcelona Clinic Liver Cancer stage, and PVTT status supported the prognostic relevance of the GBS-derived risk algorithm independent of the conventional tumor staging system. In summary, a multiparameter ML algorithm incorporating clinical characteristics, laboratory parameters, and peripheral immune signatures offers a different approach to identify patients with the greatest risk of HCC-related death.
Data from Virus-Like Particle–Drug Conjugates Induce Protective, Long-lasting Adaptive Antitumor Immunity in the Absence of Specifically Targeted Tumor Antigens
Authors: Kines Rhonda C. , Thompson Cynthia D. , Spring Sean , Li Zhenyu , de los Pinos Elisabet , Monks Stephen , Schiller John T.
Published: April 2023

Abstract
This study examined the ability of a papillomavirus-like particle drug conjugate, belzupacap sarotalocan (AU-011), to eradicate subcutaneous tumors after intravenous injection and to subsequently elicit long-term antitumor immunity in the TC-1 syngeneic murine tumor model. Upon in vitro activation with near-infrared light (NIR), AU-011–mediated cell killing was proimmunogenic in nature, resulting in the release of damage-associated molecular patterns such as DNA, ATP, and HMGB-1, activation of caspase-1, and surface relocalization of calreticulin and HSP70 on killed tumor cells. A single in vivo administration of AU-011 followed by NIR caused rapid cell death, leading to long-term tumor regression in ∼50% of all animals. Within hours of treatment, calreticulin surface expression, caspase-1 activation, and depletion of immunosuppressive leukocytes were observed in tumors. Combination of AU-011 with immune-checkpoint inhibitor antibodies, anti–CTLA-4 or anti–PD-1, improved therapeutic efficacy, resulting in 70% to 100% complete response rate that was durable 100 days after treatment, with 50% to 80% of those animals displaying protection from secondary tumor rechallenge. Depletion of CD4+ or CD8+ T cells, either at the time of AU-011 treatment or secondary tumor rechallenge of tumor-free mice, indicated that both cell populations are vital to AU-011′s ability to eradicate primary tumors and induce long-lasting antitumor protection. Tumor-specific CD8+ T-cell responses could be observed in circulating peripheral blood mononuclear cells within 3 weeks of AU-011 treatment. These data, taken together, support the conclusion that AU-011 has a direct cytotoxic effect on tumor cells and induces long-term antitumor immunity, and this activity is enhanced when combined with checkpoint inhibitor antibodies.
Data from Intratumoral Delivery of a PD-1–Blocking scFv Encoded in Oncolytic HSV-1 Promotes Antitumor Immunity and Synergizes with TIGIT Blockade
Authors: Lin Chaolong , Ren Wenfeng , Luo Yong , Li Shaopeng , Chang Yating , Li Lu , Xiong Dan , Huang Xiaoxuan , Xu Zilong , Yu Zeng , Wang Yingbin , Zhang Jun , Huang Chenghao , Xia Ningshao
Published: April 2023

Abstract
Oncolytic virotherapy can lead to systemic antitumor immunity, but the therapeutic potential of oncolytic viruses in humans is limited due to their insufficient ability to overcome the immunosuppressive tumor microenvironment (TME). Here, we showed that locoregional oncolytic virotherapy upregulated the expression of PD-L1 in the TME, which was mediated by virus-induced type I and type II IFNs. To explore PD-1/PD-L1 signaling as a direct target in tumor tissue, we developed a novel immunotherapeutic herpes simplex virus (HSV), OVH-aMPD-1, that expressed a single-chain variable fragment (scFv) against PD-1 (aMPD-1 scFv). The virus was designed to locally deliver aMPD-1 scFv in the TME to achieve enhanced antitumor effects. This virus effectively modified the TME by releasing damage-associated molecular patterns, promoting antigen cross-presentation by dendritic cells, and enhancing the infiltration of activated T cells; these alterations resulted in antitumor T-cell activity that led to reduced tumor burdens in a liver cancer model. Compared with OVH, OVH-aMPD-1 promoted the infiltration of myeloid-derived suppressor cells (MDSC), resulting in significantly higher percentages of CD155+ granulocytic-MDSCs (G-MDSC) and monocytic-MDSCs (M-MDSC) in tumors. In combination with TIGIT blockade, this virus enhanced tumor-specific immune responses in mice with implanted subcutaneous tumors or invasive tumors. These findings highlighted that intratumoral immunomodulation with an OV expressing aMPD-1 scFv could be an effective stand-alone strategy to treat cancers or drive maximal efficacy of a combination therapy with other immune checkpoint inhibitors.
Data from CD19/CD22 Dual-Targeted CAR T-cell Therapy for Relapsed/Refractory Aggressive B-cell Lymphoma: A Safety and Efficacy Study
Authors: Wei Guoqing , Zhang Yanlei , Zhao Houli , Wang Yiyun , Liu Yandan , Liang Bin , Wang Xiujian , Xu Huijun , Cui Jiazhen , Wu Wenjun , Zhao Kui , Nagler Arnon , Chang Alex H. , Hu Yongxian , Huang He
Published: April 2023

Abstract
Chimeric antigen receptor (CAR) T-cell therapies that target either CD19 or CD22 alone have potent antilymphoma effects. However, antigen escape–mediated relapse often occurs. CAR T cells targeting both CD19 and CD22 may overcome this limitation. In this study, we developed bispecific CAR T cells simultaneously recognizing CD19- and CD22-expressing targets and assessed their safety and efficacy profiles in patients with relapsed/refractory aggressive B-cell lymphoma. Twenty-four patients were screened, and 16 were found eligible for the study. CAR T-cell–associated toxicities were recorded. Responses, overall survival (OS), and progression-free survival (PFS) were assessed. Of the 16 eligible patients, 14 (87.5%) achieved objective response and 10 (62.5%) achieved complete response (CR). The 2-year OS and PFS rates were 77.3% and 40.2%, respectively. Achieving CR (P = 0.046) and the number of prior chemotherapy lines (n = 2; P = 0.047) were independent prognostic factors associated with favorable PFS. The 2-year OS and PFS among patients who achieved CR were higher than among those who did not (P = 0.015 and P < 0.001, respectively). The 2-year PFS among patients who received two prior lines of chemotherapy was higher than that among patients who received more than two lines of chemotherapy (P = 0.049); OS did not differ between the groups. Severe grade 4 cytokine-release syndrome (CRS) was observed in 1 patient; 4 and 11 patients had grades 1 and 2 CRS, respectively. No patients developed neurotoxicity. CD19/CD22 dual-targeted CAR T cells may be a safe, potent antilymphoma cell-based targeted immunotherapy.
Data from TIGIT-Fc Promotes Antitumor Immunity
Authors: Shen Xian , Fu Wenyan , Wei Yongpeng , Zhu Junle , Yu Yue , Lei Changhai , Zhao Jian , Hu Shi
Published: April 2023

Abstract
T-cell immunoreceptor with Ig and ITIM domains (TIGIT) is a checkpoint receptor that mediates both T-cell and natural killer (NK)–cell exhaustion in tumors. An Fc-TIGIT fusion protein was shown to induce an immune-tolerance effect in a previous report, but the relevance of the TIGIT-Fc protein to tumor immunity is unknown. Here, we found that TIGIT-Fc promotes, rather than suppresses, tumor immunity. TIGIT-Fc treatment promoted the effector function of CD8+ T and NK cells in several tumor-bearing mouse models. TIGIT-Fc treatment resulted in potent T cell– and NK cell–mediated tumor reactivity, sustained memory-induced immunity in tumor rechallenge models, enhanced therapeutic effects via an antibody against PD-L1, and induction of Th1 development in CD4+ T cells. TIGIT-Fc showed a potent antibody-dependent cell-mediated cytotoxicity effect but had no intrinsic effect on tumor cell development. Our findings elucidate the role of TIGIT-Fc in tumor immune reprogramming, suggesting that TIGIT-Fc treatment alone or in combination with other checkpoint receptor blockers is a promising anticancer therapeutic strategy.
Data from Glycans as Immune Checkpoints: Removal of Branched N-glycans Enhances Immune Recognition Preventing Cancer Progression
Authors: Silva Mariana C. , Fernandes Ângela , Oliveira Maria , Resende Carlos , Correia Alexandra , de-Freitas-Junior Julio C. , Lavelle Aonghus , Andrade-da-Costa Jéssica , Leander Magdalena , Xavier-Ferreira Helena , Bessa José , Pereira Carina , Henrique Rui M. , Carneiro Fátima , Dinis-Ribeiro Mário , Marcos-Pinto Ricardo , Lima Margarida , Lepenies Bernd , Sokol Harry , Machado José C. , Vilanova Manuel , Pinho Salomé S.
Published: April 2023

Abstract
Tumor growth is accompanied with dramatic changes in the cellular glycome, such as the aberrant expression of complex branched N-glycans. However, the role of this protumoral N-glycan in immune evasion and whether its removal contributes to enhancement of immune recognition and to unleashing an antitumor immune response remain elusive. We demonstrated that branched N-glycans are used by colorectal cancer cells to escape immune recognition, instructing the creation of immunosuppressive networks through inhibition of IFNγ. The removal of this “glycan-mask” exposed immunogenic mannose glycans that potentiated immune recognition by DC-SIGN–expressing immune cells, resulting in an effective antitumor immune response. We revealed a glycoimmune checkpoint in colorectal cancer, highlighting the therapeutic efficacy of its deglycosylation to potentiate immune recognition and, thus, improving cancer immunotherapy.
Data from Targeting Triple-Negative Breast Cancer with Combination Therapy of EGFR CAR T Cells and CDK7 Inhibition
Authors: Xia Lin , Zheng Zaozao , Liu Jun-yi , Chen Yu-jie , Ding Jiancheng , Hu Guo-sheng , Hu Ya-hong , Liu Suling , Luo Wen-xin , Xia Ning-shao , Liu Wen
Published: April 2023

Abstract
EGFR-targeted chimeric antigen receptor (CAR) T cells are potent and specific in suppressing the growth of triple-negative breast cancer (TNBC) in vitro and in vivo. However, in this study, a subset of mice soon acquired resistance, which limits the potential use of EGFR CAR T cells. We aimed to find a way to overcome the observed resistance. Transcriptomic analysis results revealed that EGFR CAR T-cell treatment induced a set of immunosuppressive genes, presumably through IFNγ signaling, in EGFR CAR T-cell–resistant TNBC tumors. The EGFR CAR T-cell–induced immunosuppressive genes were associated with EGFR CAR T-cell–activated enhancers and were especially sensitive to THZ1, a CDK7 inhibitor we screened out of a panel of small molecules targeting epigenetic modulators. Accordingly, combination therapy with THZ1 and EGFR CAR T cells suppressed immune resistance, tumor growth, and metastasis in TNBC tumor models, including human MDA-MB-231 cell–derived and TNBC patient–derived xenografts, and mouse EMT6 cell–derived allografts. Taken together, we demonstrated that transcriptional modulation using epigenetic inhibitors could overcome CAR T-cell therapy–induced immune resistance, thus providing a therapeutic avenue for treating TNBC in the clinic.
Data from The Expression of Adenosine A2B Receptor on Antigen-Presenting Cells Suppresses CD8+ T-cell Responses and Promotes Tumor Growth
Authors: Chen Siqi , Akdemir Imran , Fan Jie , Linden Joel , Zhang Bin , Cekic Caglar
Published: April 2023

Abstract
Accumulating evidence suggests that inhibiting adenosine-generating ecto-enzymes (CD39 and CD73) and/or adenosine A2A or A2B receptors (R) stimulates antitumor immunity and limits tumor progression. Although activating A2ARs or A2BRs causes similar immunosuppressive and protumoral functions, few studies have investigated the distinct role of A2BR in cancer. Here, we showed that A2BR expression by hematopoietic cells was primarily responsible for promoting tumor growth. Deletion of A2BR profoundly enhanced anticancer T-cell immunity. Although T-cell A2BR plays an insignificant role for A2BR-mediated immunosuppression and tumor promotion, A2BR deficiency in tumor-bearing mice caused increased infiltration of myeloid and CD103+ dendritic cells, which was associated with more effective cross-priming of adoptively transferred tumor antigen–specific CD8+ T cells. A2BR deletion also intrinsically favored accumulation of myeloid and CD11bdim antigen-presenting cells (APC) in the tumor microenvironment. Both myeloid-specific or CD11c-specific conditional deletion of A2BR delayed primary tumor growth. Myeloid, but not CD11c-specific conditional, depletion delayed lung metastasis. Pharmacologic blockade of A2BR improved the antitumor effect of adoptive T-cell therapy. Overall, these results suggested that A2BR expression on myeloid cells and APCs indirectly suppressed CD8+ T-cell responses and promoted metastasis. These data provide a strong rationale to combine A2BR inhibition with T-cell–based immunotherapy for the treatment of tumor growth and metastasis.