bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Combining DNA Vaccine and AIDA-1 in Attenuated Salmonella Activates Tumor-Specific CD4+ and CD8+ T-cell Responses
Authors: Mei Yu , Zhao Lixiang , Liu Yonghao , Gong Huanle , Song Yuan , Lei Lei , Zhu Ying , Jin Ziqi , Ma Shoubao , Hu Bo , Sun Qing , Liu Haiyan
Published: April 2023

Abstract
Stimulation of tumor-specific responses in both CD4+ and CD8+ T cells has been a challenge for effective tumor vaccines. We designed a vaccine vector containing the AIDA-1 autotransporter and DNA vaccine elements, generating a murine melanoma vaccine that was delivered by the attenuated Salmonella strain SL7207. Growth of murine subcutaneous melanoma was significantly inhibited by intranasal immunization with the Salmonella tumor vaccine. The vaccine activated tumor-specific CD4+ and CD8+ T-cell responses, with increased T-cell proliferation, tumor antigen–specific Th1 cytokine production, increased percentages of tetramer positive cells, and cytotoxicity. CD4+ or CD8+ T-cell depletion resulted in the loss of antitumor activity of the Salmonella tumor vaccine, suggesting that the efficacy of the vaccine was dependent on both CD4+ and CD8+ T cells. Lung metastasis of the tumor was also inhibited by vaccine treatment. Similarly, the percentages of tumor-specific Th1 cytokine production by CD4+ and CD8+ T cells in the spleen, tumor, and bronchoalveolar lavage were increased after vaccine treatment. Tumor-specific proliferation of CD4+ and CD8+ T cells was also promoted by the vaccine. Tetramer staining and cytotoxicity assay showed enhanced tumor-specific CD8+ T-cell response after vaccine treatment. Therefore, the Salmonella tumor vaccine could activate both tumor-specific CD4+ and CD8+ T-cell responses. This vaccine strategy may be widely applicable to the development of oral or nasal vaccines against tumors. Cancer Immunol Res; 5(6); 503–14. ©2017 AACR.
Data from ImmunoMap: A Bioinformatics Tool for T-cell Repertoire Analysis
Authors: Sidhom John-William , Bessell Catherine A. , Havel Jonathan J. , Kosmides Alyssa , Chan Timothy A. , Schneck Jonathan P.
Published: April 2023

Abstract
Despite a dramatic increase in T-cell receptor (TCR) sequencing, few approaches biologically parse the data in a fashion that both helps yield new information about immune responses and may guide immunotherapeutic interventions. To address this issue, we developed a method, ImmunoMap, that utilizes a sequence analysis approach inspired by phylogenetics to examine TCR repertoire relatedness. ImmunoMap analysis of the CD8 T-cell response to self-antigen (Kb-TRP2) or to a model foreign antigen (Kb-SIY) in naïve and tumor-bearing B6 mice showed differences in the T-cell repertoire of self- versus foreign antigen-specific responses, potentially reflecting immune pressure by the tumor, and also detected lymphoid organ–specific differences in TCR repertoires. When ImmunoMap was used to analyze clinical trial data of tumor-infiltrating lymphocytes from patients being treated with anti–PD-1, ImmunoMap, but not standard TCR sequence analyses, revealed a clinically predicative signature in pre- and posttherapy samples. Cancer Immunol Res; 6(2); 151–62. ©2017 AACR.
Data from Cripto-1 Plasmid DNA Vaccination Targets Metastasis and Cancer Stem Cells in Murine Mammary Carcinoma
Authors: Witt Kristina , Ligtenberg Maarten A. , Conti Laura , Lanzardo Stefania , Ruiu Roberto , Wallmann Tatjana , Tufvesson-Stiller Helena , Chambers Benedict J. , Rolny Charlotte , Lladser Alvaro , Lundqvist Andreas , Cavallo Federica , Kiessling Rolf
Published: April 2023

Abstract
Metastatic breast cancer is a fatal disease that responds poorly to treatment. Cancer vaccines targeting antigens expressed by metastatic breast cancer cells and cancer stem cells could function as anticancer therapies. Cripto-1 is an oncofetal protein overexpressed in invasive breast cancer and cancer-initiating cells. In this study, we explored the potential of a Cripto-1–encoding DNA vaccine to target breast cancer in preclinical mouse models. BALB/c mice and BALB-neuT mice were treated with a DNA vaccine encoding mouse Cripto-1 (mCr-1). BALB/c mice were challenged with murine breast cancer 4T1 cells or TUBO spheres; BALB-neuT mice spontaneously developed breast cancer. Tumor growth was followed in all mouse models and lung metastases were evaluated. In vitro assays were performed to identify the immune response elicited by vaccination. Vaccination against mCr-1 reduced primary tumor growth in the 4T1 metastatic breast cancer model and reduced lung metastatic burden. In BALB-neuT mice, because the primary tumors are Cripto-1 negative, vaccination against mCr-1 did not affect primary tumors but did reduce lung metastatic burden. Spheroid-cultured TUBO cells, derived from a BALB/neuT primary tumor, develop a cancer stem cell–like phenotype and express mCr-1. We observed reduced tumor growth in vaccinated mice after challenge with TUBO spheres. Our data indicate that vaccination against Cripto-1 results in a protective immune response against mCr-1 expressing and metastasizing cells. Targeting Cripto-1 by vaccination holds promise as an immunotherapy for treatment of metastatic breast cancer. Cancer Immunol Res; 6(11); 1417–25. ©2018 AACR.
Data from Disruption of IFN-I Signaling Promotes HER2/Neu Tumor Progression and Breast Cancer Stem Cells
Authors: Castiello Luciano , Sestili Paola , Schiavoni Giovanna , Dattilo Rosanna , Monque Domenica M. , Ciaffoni Fiorella , Iezzi Manuela , Lamolinara Alessia , Sistigu Antonella , Moschella Federica , Pacca Anna Maria , Macchia Daniele , Ferrantini Maria , Zeuner Ann , Biffoni Mauro , Proietti Enrico , Belardelli Filippo , Aricò Eleonora
Published: April 2023

Abstract
Type I interferon (IFN-I) is a class of antiviral immunomodulatory cytokines involved in many stages of tumor initiation and progression. IFN-I acts directly on tumor cells to inhibit cell growth and indirectly by activating immune cells to mount antitumor responses. To understand the role of endogenous IFN-I in spontaneous, oncogene-driven carcinogenesis, we characterized tumors arising in HER2/neu transgenic (neuT) mice carrying a nonfunctional mutation in the IFNI receptor (IFNAR1). Such mice are unresponsive to this family of cytokines. Compared with parental neu+/− mice (neuT mice), IFNAR1−/− neu+/− mice (IFNAR-neuT mice) showed earlier onset and increased tumor multiplicity with marked vascularization. IFNAR-neuT tumors exhibited deregulation of genes having adverse prognostic value in breast cancer patients, including the breast cancer stem cell (BCSC) marker aldehyde dehydrogenase-1A1 (ALDH1A1). An increased number of BCSCs were observed in IFNAR-neuT tumors, as assessed by ALDH1A1 enzymatic activity, clonogenic assay, and tumorigenic capacity. In vitro exposure of neuT+ mammospheres and cell lines to antibodies to IFN-I resulted in increased frequency of ALDH+ cells, suggesting that IFN-I controls stemness in tumor cells. Altogether, these results reveal a role of IFN-I in neuT-driven spontaneous carcinogenesis through intrinsic control of BCSCs. Cancer Immunol Res; 6(6); 658–70. ©2018 AACR.
Data from CCL20 Expression by Tumor-Associated Macrophages Predicts Progression of Human Primary Cutaneous Melanoma
Authors: Samaniego Rafael , Gutiérrez-González Alejandra , Gutiérrez-Seijo Alba , Sánchez-Gregorio Sandra , García-Giménez Jorge , Mercader Enrique , Márquez-Rodas Iván , Avilés José Antonio , Relloso Miguel , Sánchez-Mateos Paloma
Published: April 2023

Abstract
The chemokine axis CCR6/CCL20 is involved in cancer progression in a variety of tumors. Here, we show that CCR6 is expressed by melanoma cells. The CCR6 ligand, CCL20, induces migration and proliferation in vitro, and enhances tumor growth and metastasis in vivo. Confocal analysis of melanoma tissues showed that CCR6 is expressed by tumor cells, whereas CCL20 is preferentially expressed by nontumoral cells in the stroma of certain tumors. Stromal CCL20, but not tumoral CCR6, predicted poor survival in a cohort of 40 primary melanoma patients. Tumor-associated macrophages (TAM), independently of their M1/M2 polarization profile, were identified as the main source of CCL20 in primary melanomas that developed metastasis. In addition to CCL20, TAMs expressed TNF and VEGF-A protumoral cytokines, suggesting that melanoma progression is supported by macrophages with a differential activation state. Our data highlight the synergistic interaction between melanoma tumor cells and prometastatic macrophages through a CCR6/CCL20 paracrine loop. Stromal levels of CCL20 in primary melanomas may be a clinically useful marker for assessing patient risk, making treatment decisions, and planning or analyzing clinical trials. Cancer Immunol Res; 6(3); 267–75. ©2018 AACR.
Data from The Clinical Activity of PD-1/PD-L1 Inhibitors in Metastatic Non–Clear Cell Renal Cell Carcinoma
Authors: McKay Rana R. , Bossé Dominick , Xie Wanling , Wankowicz Stephanie A.M. , Flaifel Abdallah , Brandao Raphael , Lalani Aly-Khan A. , Martini Dylan J. , Wei Xiao X. , Braun David A. , Van Allen Eliezer , Castellano Daniel , De Velasco Guillermo , Wells J. Connor , Heng Daniel Y. , Fay Andre P. , Schutz Fabio A. , Hsu JoAnn , Pal Sumanta K. , Lee Jae Lyun , Hsieh James J. , Harshman Lauren C. , Signoretti Sabina , Motzer Robert J. , Feldman Darren , Choueiri Toni K.
Published: April 2023

Abstract
Programmed death 1 (PD-1) and PD ligand 1 (PD-L1) inhibitors have shown activity in metastatic clear cell renal cell carcinoma (ccRCC). Data on the activity of these agents in patients with non–clear cell RCC (nccRCC) or patients with sarcomatoid/rhabdoid differentiation are limited. In this multicenter analysis, we explored the efficacy of PD-1/PD-L1 inhibitors in patients with nccRCC or sarcomatoid/rhabdoid differentiation. Baseline and follow-up demographic, clinical, treatment, and radiographic data were collected. The primary endpoint was objective response rate. Secondary endpoints include time-to-treatment failure (TTF), overall survival (OS), and biomarker correlates. Forty-three patients were included: papillary (n = 14; 33%), chromophobe (n = 10; 23%), unclassified (n = 9; 21%), translocation (n = 3; 7%), and ccRCC with sarcomatoid differentiation (n = 7, 16%). Of those 43 patients, 11 patients (26%) had sarcomatoid and/or rhabdoid differentiation (n = 7 with ccRCC; n = 4 nccRCC). Overall, 8 patients (19%) objectively responded, including 4 patients (13%) who received PD-1/PD-L1 monotherapy. Responses were observed in patients with ccRCC with sarcomatoid and/or rhabdoid differentiation (n = 3/7, 43%), translocation RCC (n = 1/3, 33%), and papillary RCC (n = 4/14, 29%). The median TTF was 4.0 months [95% confidence interval (CI), 2.8–5.5] and median OS was 12.9 months (95% CI, 7.4–not reached). No specific genomic alteration was associated with clinical benefit. Modest antitumor activity for PD-1/PD-L1–blocking agents was observed in some patients with nccRCC. Further prospective studies are warranted to investigate the efficacy of PD-1/PD-L1 blockade in this heterogeneous patient population. Cancer Immunol Res; 6(7); 758–65. ©2018 AACR.
Data from Association of Tumor Microenvironment T-cell Repertoire and Mutational Load with Clinical Outcome after Sequential Checkpoint Blockade in Melanoma
Authors: Yusko Erik , Vignali Marissa , Wilson Richard K. , Mardis Elaine R. , Hodi F. Stephen , Horak Christine , Chang Han , Woods David M. , Robins Harlan , Weber Jeffrey
Published: April 2023

Abstract
To understand prognostic factors for outcome between differentially sequenced nivolumab and ipilimumab in a randomized phase II trial, we measured T-cell infiltration and PD-L1 by IHC, T-cell repertoire metrics, and mutational load within the tumor. We used next-generation sequencing (NGS) and assessed the association of those parameters with response and overall survival. Immunosequencing of the T-cell receptor β-chain locus (TCRβ) from DNA of 91 pretreatment tumor samples and an additional 22 pairs of matched pre- and posttreatment samples from patients who received nivolumab followed by ipilimumab (nivo/ipi), or the reverse (ipi/nivo), was performed to measure T-cell clonality and fraction. Mutational and neoantigen load were also assessed by NGS in 82 of the 91 patients. Tumors were stained using IHC for PD-L1+ and CD8+ T cells. Pretreatment tumor TCR clonality and neoantigen load were marginally associated with best response with nivo/ipi (P = 0.04 and 0.05, respectively), but not with ipi/nivo. Amalgamated pretreatment mutational load and tumor T-cell fraction were significantly associated with best response with nivo/ipi (P = 0.002). Pretreatment PD-L1 staining intensity and CD8+ T-cell counts were correlated with T-cell fraction and clonality, but not mutational or neoantigen load. Patients with increased T-cell fraction posttreatment at week 13 had a 30-fold increased likelihood of survival (P = 0.002). Mutational and neoantigen load, and T-cell infiltrate within the tumor, were associated with outcome of sequential checkpoint inhibition using nivolumab then ipilimumab, but not when ipilimumab was administered before nivolumab.
Data from Enhanced Cancer Immunotherapy with Smad3-Silenced NK-92 Cells
Authors: Wang Qing-Ming , Tang Patrick Ming-Kuen , Lian Guang-Yu , Li Chunjie , Li Jinhong , Huang Xiao-Ru , To Ka-Fai , Lan Hui-Yao
Published: April 2023

Abstract
Natural killer (NK) cells, early effectors in anticancer immunity, are paralyzed by TGFβ1, an immunosuppressive cytokine produced by cancer cells. Development and activity of NK cells are largely inhibited in the Smad3-dependent tumor microenvironment. Here, we used genetic engineering to generate a stable SMAD3-silencing human NK cell line, NK-92-S3KD, whose cancer-killing activity and cytokine production were significantly enhanced under TGFβ1-rich condition compared with the parental cell line. Interestingly, we identified that the IFNG gene is a direct E4BP4 target gene. Thus, silencing of SMAD3 allows upregulation of E4BP4 that subsequently promoting interferon-γ (IFNγ) production in the NK-92-S3KD cells. More importantly, NK-92-S3KD immunotherapy increases the production of not only IFNγ, but also granzyme B and perforin in tumors; therefore, inhibiting cancer progression in two xenograft mouse models with human hepatoma (HepG2) and melanoma (A375). Thus, the NK-92-S3KD cell line may be useful for the clinical immunotherapy of cancer. Cancer Immunol Res; 6(8); 965–77. ©2018 AACR.
Data from Constitutive IDO1 Expression in Human Tumors Is Driven by Cyclooxygenase-2 and Mediates Intrinsic Immune Resistance
Authors: Hennequart Marc , Pilotte Luc , Cane Stefania , Hoffmann Delia , Stroobant Vincent , Plaen Etienne De , Eynde Benoît J. Van den
Published: April 2023

Abstract
Tumors use various mechanisms to avoid immune destruction. Cyclooxygenase-2 (COX-2) expression may be a driver of immune suppression in melanoma, but the mechanisms involved remain elusive. Here, we show that COX-2 expression drives constitutive expression of indoleamine 2,3-dioxygenase 1 (IDO1) in human tumor cells. IDO1 is an immunosuppressive enzyme that degrades tryptophan. In a series of seven human tumor lines, constitutive IDO1 expression depends on COX-2 and prostaglandin E2 (PGE2), which, upon autocrine signaling through the EP receptor, activates IDO1 via the PKC and PI3K pathways. COX-2 expression itself depends on the MAPK pathway, which therefore indirectly controls IDO1 expression. Most of these tumors carry PI3K or MAPK oncogenic mutations, which may favor constitutive IDO1 expression. Celecoxib treatment promoted immune rejection of IDO1-expressing human tumor xenografts in immunodeficient mice reconstituted with human allogeneic lymphocytes. This effect was associated with a reduced expression of IDO1 in those ovarian SKOV3 tumors and an increased infiltration of CD3+ and CD8+ cells. Our results highlight the role of COX-2 in constitutive IDO1 expression by human tumors and substantiate the use of COX-2 inhibitors to improve the efficacy of cancer immunotherapy, by reducing constitutive IDO1 expression, which contributes to the lack of T-cell infiltration in “cold” tumors, which fail to respond to immunotherapy. Cancer Immunol Res; 5(8); 695–709. ©2017 AACR.
Data from Introduction of Genetically Modified CD3ζ Improves Proliferation and Persistence of Antigen-Specific CTLs
Authors: Miyao Kotaro , Terakura Seitaro , Okuno Shingo , Julamanee Jakrawadee , Watanabe Keisuke , Hamana Hiroshi , Kishi Hiroyuki , Sakemura Reona , Koyama Daisuke , Goto Tatsunori , Nishida Tetsuya , Murata Makoto , Kiyoi Hitoshi
Published: April 2023

Abstract
The clinical efficacy of T-cell therapies based on T cells transduced with genes encoding tumor-specific T-cell receptors (TCR-T) is related to the in vivo persistence of the T cells. To improve persistence without modifying TCR affinity, we instead modified intracellular signaling, using artificial T cell–activating adapter molecules (ATAM), generated by inserting the intracellular domain (ICD) of activating T-cell signaling moieties into CD3ζ. ATAMs with the ICD of either CD28 or 4-1BB were generated, assembled into the TCR complex as a part of CD3ζ, and enhanced downstream signaling from the supramolecular activation cluster. ATAMs were retrovirally introduced into human CMV-specific or NY-ESO-1–specific TCR-transduced CD8+ T lymphocytes, and downstream functionality was then examined. ATAM-transduced NY-ESO-1 TCR-T cells were also investigated using the U266-xenograft mouse model. ATAMs were successfully transduced and localized to the cell membrane. ATAM-transduced CMV-specific T cells retained their cytotoxic activity and cytokine production against peptide-pulsed target cells without altering antigen-specificity and showed resistance to activation-induced cell death. Upon both single and repeated stimulation, CD3ζ/4-1BB–transduced T cells had superior proliferation to the CD3ζ-transduced T cells in both the CMV-specific and the NY-ESO-1 TCR-T models and significantly improved antitumor activity compared with untransduced T cells both in vitro and in a mouse xenograft model. ATAM-transduced TCR-T cells demonstrated improved proliferation and persistence in vitro and in vivo. This strategy to control the intracellular signaling of TCR-T cells by ATAM transduction in combination with various tumor-specific TCRs may improve the efficacy of TCR-T therapy. Cancer Immunol Res; 6(6); 733–44. ©2018 AACR.
Data from Automated Analysis of Lymphocytic Infiltration, Tumor Budding, and Their Spatial Relationship Improves Prognostic Accuracy in Colorectal Cancer
Authors: Nearchou Ines P. , Lillard Kate , Gavriel Christos G. , Ueno Hideki , Harrison David J. , Caie Peter D.
Published: April 2023

Abstract
Both immune profiling and tumor budding significantly correlate with colorectal cancer patient outcome but are traditionally reported independently. This study evaluated the association and interaction between lymphocytic infiltration and tumor budding, coregistered on a single slide, in order to determine a more precise prognostic algorithm for patients with stage II colorectal cancer. Multiplexed immunofluorescence and automated image analysis were used for the quantification of CD3+CD8+ T cells, and tumor buds (TBs), across whole slide images of three independent cohorts (training cohort: n = 114, validation cohort 1: n = 56, validation cohort 2: n = 62). Machine learning algorithms were used for feature selection and prognostic risk model development. High numbers of TBs [HR = 5.899; 95% confidence interval (CI) 1.875–18.55], low CD3+ T-cell density (HR = 9.964; 95% CI, 3.156–31.46), and low mean number of CD3+CD8+ T cells within 50 μm of TBs (HR = 8.907; 95% CI, 2.834–28.0) were associated with reduced disease-specific survival. A prognostic signature, derived from integrating TBs, lymphocyte infiltration, and their spatial relationship, reported a more significant cohort stratification (HR = 18.75; 95% CI, 6.46–54.43), than TBs, a lymphocytic infiltration score, or pT stage. This was confirmed in two independent validation cohorts (HR = 12.27; 95% CI, 3.524–42.73; HR = 15.61; 95% CI, 4.692–51.91). The investigation of the spatial relationship between lymphocytes and TBs within the tumor microenvironment improves accuracy of prognosis of patients with stage II colorectal cancer through an automated image analysis and machine learning workflow.
Data from Adaptive NK Cells Resist Regulatory T-cell Suppression Driven by IL37
Authors: Sarhan Dhifaf , Hippen Keli L. , Lemire Amanda , Hying Skyler , Luo Xianghua , Lenvik Todd , Curtsinger Julie , Davis Zachary , Zhang Bin , Cooley Sarah , Cichocki Frank , Blazar Bruce R. , Miller Jeffrey S.
Published: April 2023

Abstract
Natural killer (NK) cells are capable of fighting viral infections and cancer. However, these responses are inhibited by immune suppressor cells in the tumor microenvironment. Tumor progression promotes the recruitment and generation of intratumoral regulatory T cells (Treg), associated with a poor prognosis in cancer patients. Here, we show that canonical NK cells are highly susceptible to Treg-mediated suppression, in contrast to highly resistant CD57+ FcϵRγ−NKG2C+ adaptive (CD56+CD3−) NK cells that expand in cytomegalovirus exposed individuals. Specifically, Tregs suppressed canonical but not adaptive NK-cell proliferation, IFNγ production, degranulation, and cytotoxicity. Treg-mediated suppression was associated with canonical NK-cell downregulation of TIM3, a receptor that activates NK-cell IFNγ production upon ligand engagement, and upregulation of the NK-cell inhibitory receptors PD-1 and the IL1 receptor family member, IL1R8 (SIGIRR or TIR8). Treg production of the IL1R8 ligand, IL37, contributed to the phenotypic changes and diminished function in Treg-suppressed canonical NK cells. Blocking PD-1, IL1R8, or IL37 abrogated Treg suppression of canonical NK cells while maintaining NK-cell TIM3 expression. Our data uncover new mechanisms of Treg-mediated suppression of canonical NK cells and identify that adaptive NK cells are inherently resistant to Treg suppression. Strategies to enhance the frequency of adaptive NK cells in the tumor microenvironment or to blunt Treg suppression of canonical NK cells will enhance the efficacy of NK-cell cancer immunotherapy. Cancer Immunol Res; 6(7); 766–75. ©2018 AACR.
Data from Intratumoral CD8+ T-cell Apoptosis Is a Major Component of T-cell Dysfunction and Impedes Antitumor Immunity
Authors: Horton Brendan L. , Williams Jason B. , Cabanov Alexandra , Spranger Stefani , Gajewski Thomas F.
Published: April 2023

Abstract
Subsets of human tumors are infiltrated with tumor antigen–specific CD8+ T cells [tumor-infiltrating lymphocytes (TILs)] despite tumor progression. These TILs are thought to be inactivated by the immunosuppressive tumor microenvironment, through the engagement of inhibitory receptors such as CTLA-4 and PD-1. However, antigen-specific CD8+ TILs are not functionally inert but are undergoing activation in situ. Here, we show that antigen-specific CD8+ TILs are actively proliferating, yet also undergo high rates of apoptosis, leading to a vicious cycle of activation and death that limits immune efficacy. Preventing CD8+ TIL apoptosis by Bcl-xL overexpression enabled accumulation and improved tumor control. Effective combination immunotherapy with an agonist 4-1BB mAb plus either CTLA-4 or PD-L1 neutralization led to a marked accumulation of specific CD8+ TILs through decreased apoptosis rather than increased T-cell entry or proliferation. Our data suggest that antigen-driven apoptosis of CD8+ TILs is a barrier to effective spontaneous antitumor immunity and should be considered as a critical factor in the development of cancer immunotherapies. Cancer Immunol Res; 6(1); 14–24. ©2017 AACR.
Data from Dual PD-1 and CTLA-4 Checkpoint Blockade Promotes Antitumor Immune Responses through CD4+Foxp3− Cell–Mediated Modulation of CD103+ Dendritic Cells
Authors: Beavis Paul A. , Henderson Melissa A. , Giuffrida Lauren , Davenport Alexander J. , Petley Emma V. , House Imran G. , Lai Junyun , Sek Kevin , Milenkovski Nicole , John Liza B. , Mardiana Sherly , Slaney Clare Y. , Trapani Joseph A. , Loi Sherene , Kershaw Michael H. , Haynes Nicole M. , Darcy Phillip K.
Published: April 2023

Abstract
Immunotherapy is widely accepted as a powerful new treatment modality for the treatment of cancer. The most successful form of immunotherapy to date has been the blockade of the immune checkpoints PD-1 and CTLA-4. Combining inhibitors of both PD-1 and CTLA-4 increases the proportion of patients who respond to immunotherapy. However, most patients still do not respond to checkpoint inhibitors, and prognostic biomarkers are currently lacking. Therefore, a better understanding of the mechanism by which these checkpoint inhibitors enhance antitumor immune responses is required to more accurately predict which patients are likely to respond and further enhance this treatment modality. Our current study of two mouse tumor models revealed that CD4+Foxp3− cells activated by dual PD-1/CTLA-4 blockade modulated the myeloid compartment, including activation of conventional CD103+ dendritic cells (DC) and expansion of a myeloid subset that produces TNFα and iNOS (TIP-DCs). CD4+Foxp3− T cell–mediated activation of CD103+ DCs resulted in enhanced IL12 production by these cells and IL12 enhanced the therapeutic effect of dual PD-1/CTLA-4 blockade. Given the importance of these myeloid subsets in the antitumor immune response, our data point to a previously underappreciated role of CD4+Foxp3− cells in modulating this arm of the antitumor immune response. Cancer Immunol Res; 6(9); 1069–81. ©2018 AACR.
Data from The Mutation-Associated Neoantigen Functional Expansion of Specific T Cells (MANAFEST) Assay: A Sensitive Platform for Monitoring Antitumor Immunity
Authors: Danilova Ludmila , Anagnostou Valsamo , Caushi Justina X. , Sidhom John-William , Guo Haidan , Chan Hok Yee , Suri Prerna , Tam Ada , Zhang Jiajia , Asmar Margueritta El , Marrone Kristen A. , Naidoo Jarushka , Brahmer Julie R. , Forde Patrick M. , Baras Alexander S. , Cope Leslie , Velculescu Victor E. , Pardoll Drew M. , Housseau Franck , Smith Kellie N.
Published: April 2023

Abstract
Mutation-associated neoantigens (MANA) are a target of antitumor T-cell immunity. Sensitive, simple, and standardized assays are needed to assess the repertoire of functional MANA-specific T cells in oncology. Assays analyzing in vitro cytokine production such as ELISpot and intracellular cytokine staining have been useful but have limited sensitivity in assessing tumor-specific T-cell responses and do not analyze antigen-specific T-cell repertoires. The FEST (Functional Expansion of Specific T cells) assay described herein integrates T-cell receptor sequencing of short-term, peptide-stimulated cultures with a bioinformatic platform to identify antigen-specific clonotypic amplifications. This assay can be adapted for all types of antigens, including MANAs via tumor exome-guided prediction of MANAs. Following in vitro identification by the MANAFEST assay, the MANA-specific CDR3 sequence can be used as a molecular barcode to detect and monitor the dynamics of these clonotypes in blood, tumor, and normal tissue of patients receiving immunotherapy. MANAFEST is compatible with high-throughput routine clinical and lab practices. Cancer Immunol Res; 6(8); 888–99. ©2018 AACR.
Data from Reversible Transgene Expression Reduces Fratricide and Permits 4-1BB Costimulation of CAR T Cells Directed to T-cell Malignancies
Authors: Mamonkin Maksim , Mukherjee Malini , Srinivasan Madhuwanti , Sharma Sandhya , Gomes-Silva Diogo , Mo Feiyan , Krenciute Giedre , Orange Jordan S. , Brenner Malcolm K.
Published: April 2023

Abstract
T cells expressing second-generation chimeric antigen receptors (CARs) specific for CD5, a T-cell surface marker present on normal and malignant T cells, can selectively kill tumor cells. We aimed to improve this killing by substituting the CD28 costimulatory endodomain (28.z) with 4-1BB (BB.z), as 28.z CD5 CAR T cells rapidly differentiated into short-lived effector cells. In contrast, 4-1BB costimulation is known to promote development of the central memory subpopulation. Here, we found BB.z CD5 CAR T cells had impaired growth compared with 28.z CD5.CAR T cells, due to increased T-cell–T-cell fratricide. We demonstrate that TRAF signaling from the 4-1BB endodomain upregulated the intercellular adhesion molecule 1, which stabilized the fratricidal immunologic synapse between CD5 CAR T cells. As the surviving BB.z CD5 CAR T cells retained the desired central memory phenotype, we aimed to circumvent the 4-1BB–mediated toxicity using a regulated expression system that reversibly inhibits CAR expression. This system minimized CAR signaling and T-cell fratricide during in vitro expansion in the presence of a small-molecule inhibitor, and restored CAR expression and antitumor function of transduced T cells in vivo. These studies reveal a mechanism by which 4-1BB costimulation impairs expansion of CD5 CAR T cells and offer a solution to mitigate this toxicity. Cancer Immunol Res; 6(1); 47–58. ©2017 AACR.
Data from Late-Stage Tumor Regression after PD-L1 Blockade Plus a Concurrent OX40 Agonist
Authors: Polesso Fanny , Weinberg Andrew D. , Moran Amy E.
Published: April 2023

Abstract
The protective capability of tumor antigen–specific T cells is regulated by costimulatory and inhibitory signals. Current approaches in cancer immunotherapy seek to restore the function of unresponsive T cells by blocking inhibitory pathways. In contrast, providing exogenous costimulatory signals to T cells also enhances antitumor functionality. By combining these two clinical approaches, we demonstrate the synergy of targeting PD-L1 together with the costimulatory molecule OX40, to enhance antitumor immunity. Concurrently blocking PD-L1 and providing a costimulatory agonist to OX40 increased the presence and functionality of tumor antigen–specific CD8+ T cells with simultaneous enhancement of T-helper type 1 (Th1)-skewed CD4+ T cells. This shift was functionally supported by increased glucose metabolism of antigen-specific CD8+ T cells and the acquisition of granzyme B by regulatory T cells. Together, this mechanism promoted tumor regression of late-stage tumors beyond that achieved by either blockade as monotherapy. These findings indicate that targeting both T-cell intrinsic (OX40) and extrinsic (PD-L1) regulatory molecules increases the bioenergetic potential of T cells, thereby expanding functional and tumor antigen–specific T cells.
Data from Irreversible Electroporation Combined with Checkpoint Blockade and TLR7 Stimulation Induces Antitumor Immunity in a Murine Pancreatic Cancer Model
Authors: Narayanan Jayanth S. Shankara , Ray Partha , Hayashi Tomoko , Whisenant Thomas C. , Vicente Diego , Carson Dennis A. , Miller Aaron M. , Schoenberger Stephen P. , White Rebekah R.
Published: April 2023

Abstract
Irreversible electroporation (IRE) is a nonthermal ablation technique that is used clinically in selected patients with locally advanced pancreatic cancer, but most patients develop recurrent distant metastatic disease. We hypothesize that IRE can induce an in situ vaccination effect by releasing tumor neoantigens in an inflammatory context. Using an immunocompetent mouse model, we demonstrated that IRE alone produced complete regression of subcutaneous tumors in approximately 20% to 30% of mice. IRE was not effective in immunodeficient mice. Mice with complete response to IRE demonstrated prophylactic immunity and remained tumor free when rechallenged with secondary tumors on the contralateral flank. CD8+ T cells from IRE-responsive mice were reactive against peptides representing model-inherent alloantigens and conferred protection against tumor challenge when adoptively transferred into immunocompromised, tumor-naïve mice. Combining IRE with intratumoral Toll-like receptor-7 (TLR7) agonist (1V270) and systemic anti-programmed death-1 receptor (PD)-1 checkpoint blockade resulted in improved treatment responses. This combination also resulted in elimination of untreated concomitant distant tumors (abscopal effects), an effect not seen with IRE alone. These results suggest that the systemic antitumor immune response triggered by IRE can be enhanced by stimulating the innate immune system with a TLR7 agonist and the adaptive immune system with anti–PD-1 checkpoint blockade simultaneously. Combinatorial approaches such as this may help overcome the immunosuppressive pancreatic cancer microenvironment.
Data from HPV Epitope Processing Differences Correlate with ERAP1 Allotype and Extent of CD8+ T-cell Tumor Infiltration in OPSCC
Authors: Reeves Emma , Wood Oliver , Ottensmeier Christian H. , King Emma V. , Thomas Gareth J. , Elliott Tim , James Edward
Published: April 2023

Abstract
Presence of tumor-infiltrating lymphocytes (TIL) predicts survival in many cancer types. In HPV-driven cancers, cervical and oropharyngeal squamous cell carcinomas (CSCC and OPSCC, respectively), numbers of infiltrating T cells, particularly CD8+ T cells, and presentation of HPV E6/E7 epitopes are associated with improved prognosis. Endoplasmic reticulum aminopeptidase 1 (ERAP1) regulates the presented peptide repertoire, trimming peptide precursors prior to MHC I loading. ERAP1 is polymorphic, and allotypic variation of ERAP1 enzyme activity has an impact on the presented peptide repertoire. Individual SNPs are associated with incidence and outcome in a number of diseases, including CSCC. Here, we highlight the requirement for ERAP1 in the generation of HPV E6/E7 epitopes and show that the functional activity of ERAP1 allotype combinations identified in OPSCC correlate with tumor-infiltrating CD8+ T-cell (CD8)/TIL (CD8/TIL) status of the tumor. Functional analyses revealed that ERAP1 allotype combinations associated with CD8/TILlow tumors have a reduced capacity to generate both a model antigen SIINFEHL and the HPV-16 E782-90 epitope LLMGTLGIV from N-terminally extended precursor peptides. In contrast, ERAP1 allotypes from CD8/TILhigh tumors generated the epitopes efficiently. These data reveal that ERAP1 function correlates with CD8/TIL numbers and, by implication, prognosis, suggesting that the presentation of HPV-16 epitopes at the cell surface, resulting in an anti-HPV T-cell response, may depend on the ERAP1 allotype combinations expressed within an individual.
Data from An IL6–Adenosine Positive Feedback Loop between CD73+ γδTregs and CAFs Promotes Tumor Progression in Human Breast Cancer
Authors: Hu Guoming , Cheng Pu , Pan Jun , Wang Shimin , Ding Qiannan , Jiang Zhou , Cheng Lu , Shao Xuan , Huang Liming , Huang Jian
Published: April 2023

Abstract
The tumor microenvironment induces immunosuppression via recruiting and expanding suppressive immune cells such as regulatory T cells (Treg) to promote cancer progression. In this study, we documented that tumor-infiltrating CD73+ γδTregs were the predominant Tregs in human breast cancer and exerted more potent immunosuppressive activity than CD4+ or CD8+ Tregs. We further demonstrated that cancer-associated fibroblast (CAF)–derived IL6, rather than TGFβ1, induced CD73+ γδTreg differentiation from paired normal breast tissues via the IL6/STAT3 pathway to produce more adenosine and become potent immunosuppressive T cells. CD73+ γδTregs could in turn promote IL6 secretion by CAFs through adenosine/A2BR/p38MAPK signaling, thereby forming an IL6–adenosine positive feedback loop. CD73+ γδTreg infiltration also impaired the tumoricidal functions of CD8+ T cells and significantly correlated with worse prognosis of patients. The data indicate that the IL6–adenosine loop between CD73+ γδTregs and CAFs is important to promote immunosuppression and tumor progression in human breast cancer, which may be critical for tumor immunotherapy.
Data from NK Cells Expressing a Chimeric Activating Receptor Eliminate MDSCs and Rescue Impaired CAR-T Cell Activity against Solid Tumors
Authors: Parihar Robin , Rivas Charlotte , Huynh Mai , Omer Bilal , Lapteva Natalia , Metelitsa Leonid S. , Gottschalk Stephen M. , Rooney Cliona M.
Published: April 2023

Abstract
Solid tumors are refractory to cellular immunotherapies in part because they contain suppressive immune effectors such as myeloid-derived suppressor cells (MDSCs) that inhibit cytotoxic lymphocytes. Strategies to reverse the suppressive tumor microenvironment (TME) should also attract and activate immune effectors with antitumor activity. To address this need, we developed gene-modified natural killer (NK) cells bearing a chimeric receptor in which the activating receptor NKG2D is fused to the cytotoxic ζ-chain of the T-cell receptor (NKG2D.ζ). NKG2D.ζ–NK cells target MDSCs, which overexpress NKG2D ligands within the TME. We examined the ability of NKG2D.ζ–NK cells to eliminate MDSCs in a xenograft TME model and improve the antitumor function of tumor-directed chimeric antigen receptor (CAR)–modified T cells. We show that NKG2D.ζ–NK cells are cytotoxic against MDSCs, but spare NKG2D ligand–expressing normal tissues. NKG2D.ζ–NK cells, but not unmodified NK cells, secrete proinflammatory cytokines and chemokines in response to MDSCs at the tumor site and improve infiltration and antitumor activity of subsequently infused CAR-T cells, even in tumors for which an immunosuppressive TME is an impediment to treatment. Unlike endogenous NKG2D, NKG2D.ζ is not susceptible to TME-mediated downmodulation and thus maintains its function even within suppressive microenvironments. As clinical confirmation, NKG2D.ζ–NK cells generated from patients with neuroblastoma killed autologous intratumoral MDSCs capable of suppressing CAR-T function. A combination therapy for solid tumors that includes both NKG2D.ζ–NK cells and CAR-T cells may improve responses over therapies based on CAR-T cells alone.
Data from Mouse PVRIG Has CD8+ T Cell–Specific Coinhibitory Functions and Dampens Antitumor Immunity
Authors: Murter Benjamin , Pan Xiaoyu , Ophir Eran , Alteber Zoya , Azulay Meir , Sen Rupashree , Levy Ofer , Dassa Liat , Vaknin Ilan , Fridman-Kfir Tal , Salomon Ran , Ravet Achinoam , Tam Ada , Levin Doron , Vaknin Yakir , Tatirovsky Evgeny , Machlenkin Arthur , Pardoll Drew , Ganguly Sudipto
Published: April 2023

Abstract
A limitation to antitumor immunity is the dysfunction of T cells in the tumor microenvironment, in part due to upregulation of coinhibitory receptors such as PD-1. Here, we describe that poliovirus receptor–related immunoglobulin domain protein (PVRIG) acts as a coinhibitory receptor in mice. Murine PVRIG interacted weakly with poliovirus receptor (PVR) but bound poliovirus receptor–like 2 (PVRL2) strongly, making the latter its principal ligand. As in humans, murine NK and NKT cells constitutively expressed PVRIG. However, when compared with humans, less PVRIG transcript and surface protein was detected in murine CD8+ T cells ex vivo. However, activated CD8+ T cells upregulated PVRIG expression. In the mouse tumor microenvironment, infiltrating CD8+ T cells expressed PVRIG whereas its ligand, PVRL2, was detected predominantly on myeloid cells and tumor cells, mirroring the expression pattern in human tumors. PVRIG-deficient mouse CD8+ T cells mounted a stronger antigen-specific effector response compared with wild-type CD8+ T cells during acute Listeria monocytogenes infection. Furthermore, enhanced CD8+ T-cell effector function inhibited tumor growth in PVRIG−/− mice compared with wild-type mice and PD-L1 blockade conferred a synergistic antitumor response in PVRIG−/− mice. Therapeutic intervention with antagonistic anti-PVRIG in combination with anti–PD-L1 reduced tumor growth. Taken together, our results suggest PVRIG is an inducible checkpoint receptor and that targeting PVRIG–PVRL2 interactions results in increased CD8+ T-cell function and reduced tumor growth.

See related article on p. 257
Data from Intravesical Ty21a Vaccine Promotes Dendritic Cells and T Cell–Mediated Tumor Regression in the MB49 Bladder Cancer Model
Authors: Domingos-Pereira Sonia , Sathiyanadan Karthik , La Rosa Stefano , Polák Lenka , Chevalier Mathieu F. , Martel Paul , Hojeij Rim , Derré Laurent , Haefliger Jacques-Antoine , Jichlinski Patrice , Nardelli-Haefliger Denise
Published: April 2023

Abstract
Preclinical data show that intravesical instillation of Ty21a/Vivotif, a commercial vaccine against typhoid fever, is an effective alternative option to standard Bacillus Calmette–Guérin (BCG) immunotherapy for non–muscle-invasive bladder cancer (NMIBC). Here, we characterized the inflammatory effects of Ty21a on the bladder and investigated the immune mechanisms underlying tumor regression toward the use of this bacterial vaccine in NMIBC patients. MB49 bladder tumor–bearing mice had significantly improved survival after intravesical instillations of Ty21a doses of 106 to 108 colony-forming units. By IHC and morphology, both BCG and Ty21a instillations were associated with bladder inflammation, which was decreased with the use of low, but effective doses of Ty21a. Flow-cytometry analysis showed a significant infiltration of T cells, natural killer (NK) cells, and myeloid cells, compared with controls, after a single dose of Ty21a, whereas this was only observed after multiple doses of BCG. The induced myeloid cells were predominantly neutrophils and Ly6C+CD103+ dendritic cells (DC), the latter being significantly more numerous after instillation of Ty21a than BCG. Ex vivo infection of human leukocytes with Ty21a, but not BCG, similarly significantly increased DC frequency. CD4+ and CD8+ T cells, but not NK cells nor neutrophils, were required for effective bladder tumor regression upon Ty21a treatment. Thus, the generation of antitumor adaptive immunity was identified as a key process underlying Ty21a-mediated treatment efficacy. Altogether, these results demonstrate mechanisms behind intravesical Ty21a therapy and suggest its potential as a safe and effective treatment for NMIBC patients.
Data from A Genetic Screen to Identify Gain- and Loss-of-Function Modifications that Enhance T-cell Infiltration into Tumors
Authors: Rogers Laura M. , Wang Zhaoming , Mott Sarah L. , Dupuy Adam J. , Weiner George J.
Published: April 2023

Abstract
T-cell–mediated cancer immunotherapies, including anti–PD-1 and T cells expressing chimeric antigen receptors (CAR-T cells), are becoming standard treatments for many cancer types. CAR-T therapy, in particular, has been successful in treating circulating, but not solid, tumors. One challenge limiting immunotherapy success is that tumors lacking T-cell infiltration do not respond to treatment. Therefore, one potential strategy to overcome resistance is to enhance the ability of T cells to traffic into tumors. Here, we describe an unbiased in vivo genetic screen approach utilizing the Sleeping Beauty mutagenesis system to identify candidate genes in T cells that might be modified to drive intratumoral T-cell accumulation. This screen identified over 400 candidate genes in three tumor models. These results indicated substantial variation in gene candidate selection, depending on the tumor model and whether or not mice were treated with anti–PD-1, yet some candidate genes were identified in all tumor models and with anti–PD-1 therapy. Inhibition of the most frequently mutated gene, Aak1, affected chemokine receptor expression and enhanced T-cell trafficking in vitro and in vivo. Screen candidates should be further validated as therapeutic targets, with particular relevance to enhancing infiltration of adoptively transferred T cells into solid tumors.
Data from Immunologic Recognition of a Shared p53 Mutated Neoantigen in a Patient with Metastatic Colorectal Cancer
Authors: Lo Winifred , Parkhurst Maria , Robbins Paul F. , Tran Eric , Lu Yong-Chen , Jia Li , Gartner Jared J. , Pasetto Anna , Deniger Drew , Malekzadeh Parisa , Shelton Thomas E. , Prickett Todd , Ray Satyajit , Kivitz Scott , Paria Biman C. , Kriley Isaac , Schrump David S. , Rosenberg Steven A.
Published: April 2023

Abstract
Adoptive cell therapy (ACT) with T cells targeting neoantigens can mediate durable responses in patients with metastatic cancer. Cell therapies targeting common shared antigens for epithelial cancers are not yet broadly available. Here, we report the identification and characterization in one patient of T-cell receptors (TCRs) recognizing mutated p53 p.R175H, which is shared among a subset of patients with cancer. Tumor-infiltrating lymphocytes were screened for recognition of mutated neoantigens in a patient with metastatic colorectal cancer. HLA-A*0201–restricted recognition of mutated p53 p.R175H was identified, and the minimal peptide epitope was HMTEVVRHC. Reactive T cells were isolated by tetramer sorting, and three TCRs were identified. These TCRs mediated recognition of commercially available ovarian cancer, uterine carcinoma, and myeloma cell lines, as well as an NIH patient–derived esophageal adenocarcinoma line that endogenously expressed p53 p.R175H and HLA-A*0201. They also mediated recognition of p53 p.R175H+ colon, breast, and leukemia cell lines after transduction with a retrovirus encoding HLA-A*0201. This work demonstrates that common shared mutated epitopes such as those found in p53 can elicit immunogenic responses and that the application of ACT may be extended to patients with any cancer histology that expresses both HLA-A*0201 and the p53 p.R175H mutation.
Data from BCMA-Targeted CAR T-cell Therapy plus Radiotherapy for the Treatment of Refractory Myeloma Reveals Potential Synergy
Authors: Smith Eric L. , Mailankody Sham , Staehr Mette , Wang Xiuyan , Senechal Brigitte , Purdon Terence J. , Daniyan Anthony F. , Geyer Mark B. , Goldberg Aaron D. , Mead Elena , Santomasso Bianca D. , Landa Jonathan , Rimner Andreas , Riviere Isabelle , Landgren Ola , Brentjens Renier J.
Published: April 2023

Abstract
We present a case of a patient with multiply relapsed, refractory myeloma whose clinical course showed evidence of a synergistic abscopal-like response to chimeric antigen receptor (CAR) T-cell therapy and localized radiotherapy (XRT). Shortly after receiving B-cell maturation antigen (BCMA)–targeted CAR T-cell therapy, the patient required urgent high-dose steroids and XRT for spinal cord compression. Despite the steroids, the patient had a durable systemic response that could not be attributed to XRT alone. Post-XRT findings included a second wave of fever and increased CRP and IL6, beginning 21 days after CAR T cells, which is late for cytokine-release syndrome from CAR T-cell therapy alone on this trial. Given this response, which resembled cytokine-release syndrome, immediately following XRT, we investigated changes in the patient's T-cell receptor (TCR) repertoire over 10 serial time points. Comparing T-cell diversity via Morisita's overlap indices (CD), we discovered that, although the diversity was initially stable after CAR T-cell therapy compared with baseline (CD = 0.89–0.97, baseline vs. 4 time points after CAR T cells), T-cell diversity changed after the conclusion of XRT, with >30% newly expanded TCRs (CD = 0.56–0.69, baseline vs. 4 time points after XRT). These findings suggest potential synergy between radiation and CAR T-cell therapies resulting in an abscopal-like response.