Journal Articles

Immune checkpoint blockade facilitates primary tumor rejection in a cDC1-independent manner without immunological memory acquisition

Spotlight 

Arisato et al. found that the LLC-2B2 subclone of LLC was universally rejected in ICB-treated WT mice and was also rejected in 36% of ICB-treated Batf3-/- mice. In Batf3-/- mice, rejection was dependent on CD8+ T cells primed by alternative XCR1- APCs, which upregulated costimulatory CD80, CD86, and CD40 in response to soluble factors secreted by LLC-2B2 cells. However, when mice that had cleared LLC-2B2 tumors were rechallenged, all WT mice rejected tumors, while most Batf3-/- mice did not, suggesting that cDC1s were important in establishing protective immune memory. Intratumoral injection of Flt3L-DCs restored protection from rechallenge.

Contributed by Lauren Hitchings

Arisato et al. found that the LLC-2B2 subclone of LLC was universally rejected in ICB-treated WT mice and was also rejected in 36% of ICB-treated Batf3-/- mice. In Batf3-/- mice, rejection was dependent on CD8+ T cells primed by alternative XCR1- APCs, which upregulated costimulatory CD80, CD86, and CD40 in response to soluble factors secreted by LLC-2B2 cells. However, when mice that had cleared LLC-2B2 tumors were rechallenged, all WT mice rejected tumors, while most Batf3-/- mice did not, suggesting that cDC1s were important in establishing protective immune memory. Intratumoral injection of Flt3L-DCs restored protection from rechallenge.

Contributed by Lauren Hitchings

ABSTRACT: Immune checkpoint blockade (ICB) provides durable therapeutic responses across multiple cancer types. Although crosstalk between T cells and conventional type 1 dendritic cells (cDC1s) is essential, the contribution of other antigen-presenting cells (APCs) to ICB-induced tumor rejection remains unclear. To address this, we show that while the majority of wild type (WT) mice rejected an immunogenic clone of Lewis lung carcinoma (LLC) following ICB, 35.7% of Batf3–/– mice, which lack the cDC1 subset, also rejected this LLC clone. ICB induced the upregulation of costimulatory markers on XCR1– APCs in the tumors and lymph nodes of Batf3–/– mice, similar to responses observed in wild-type mice. Mechanistically, conditioned culture media from LLC, but not from ICB-resistant B16F10 melanoma cells, stimulated bone marrow-derived cDC1s and cDC2s, as evidenced by the upregulation of CD40 and CD80 expression. RNA sequencing revealed that antitumor immunity-related genes were upregulated in LLC cells compared with B16F10 cells. To determine the role of cDC1-independent long-term immune memory, we rechallenged ICB-induced tumor-free mice with LLC tumors. We found that, without supplementation of cDC1s during primary rejection, Batf3–/– mice failed to spontaneously reject the rechallenged tumors. These findings demonstrate that ICB can elicit primary antitumor T cell responses against immunogenic tumors in the absence of cDC1s, whereas cDC1s are essential for the establishment of ICB-induced long-term memory. Our study underscores the importance of clinical strategies targeting both cDC1-dependent and cDC1-independent pathways to enhance the durable efficacy of ICB.

Author Info: 1. Department of Medical Oncology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan 2. Department of Respiratory Medicine, Faculty of Medici

Author Info: 1. Department of Medical Oncology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan 2. Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University, Sapporo, Japan 3. Department of Medical Oncology, Shinshu Cancer Center, Shinshu University Hospital, Matsumoto, Japan 4. Division of Molecular Psychoimmunology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan 5. Department of Medical Oncology, Hokkaido University Hospital, Sapporo, Japan 6. Division of Clinical Cancer Genomics, Hokkaido University Hospital, Sapporo, Japan 7. Quantum immunology Team, Institute for Quantum Life science, National Institute for Quantum and Radiological Science and Technology (QST), Chiba, Japan 8. Division of Molecular Neuroimmunology, Department of Homeostatic Regulation, National Institute for Physiological Sciences, National Institutes of Natural Sciences, Aichi, Japan 9. Institute for Vaccine Research and Development, Hokkaido University, Sapporo 001-0021, Japan

Enfortumab vedotin induces immunogenic cell death and shows enhanced preclinical antitumor activity when combined with a PD-1 inhibitor Featured  

Untangling the mechanism of enfortumab vedotin – an antibody–drug conjugate that targets Nectin-4 on cancer cells – Olson and Liu et al. showed that upon target binding, the drug is imported into the cell and transported to the lysosome, where MMAE is released, inducing direct cytotoxicity by disrupting microtubule formation and inducing ER stress and immunogenic cell death (ICD). Upon ICD, MMAE is released from the cell, killing nearby bystander cells. ICD also induces macrophage and DC activation, initiating protective antitumor immunity against both Nectin-4+ and Nectin-4- tumor cells. Enfortuman vedotin also synergized with anti-PD-1.

Untangling the mechanism of enfortumab vedotin – an antibody–drug conjugate that targets Nectin-4 on cancer cells – Olson and Liu et al. showed that upon target binding, the drug is imported into the cell and transported to the lysosome, where MMAE is released, inducing direct cytotoxicity by disrupting microtubule formation and inducing ER stress and immunogenic cell death (ICD). Upon ICD, MMAE is released from the cell, killing nearby bystander cells. ICD also induces macrophage and DC activation, initiating protective antitumor immunity against both Nectin-4+ and Nectin-4- tumor cells. Enfortuman vedotin also synergized with anti-PD-1.

ABSTRACT: Enfortumab vedotin is a Nectin-4-directed antibody-drug conjugate designed to deliver the microtubule-disrupting agent monomethyl auristatin E (MMAE) to tumor cells. Using preclinical models of urothelial cancer (UC), we expand the understanding of the multifaceted mechanism of action for enfortumab vedotin that includes direct cytotoxicity on Nectin-4-positive tumor cells, indirect bystander effect on neighboring Nectin-4-negative tumor cells, and MMAE-mediated induction of immunogenic cell death (ICD) and associated increase in activated immune cells in the tumor microenvironment. Importantly, vaccination with enfortumab vedotin-treated tumor cells results in protection against tumor rechallenge in mice, consistent with antitumor immunity. MMAE-mediated ICD induction modulates the tumor microenvironment in a complementary manner to immune checkpoint inhibition. Accordingly, enfortumab vedotin plus PD-1 inhibitor shows enhanced antitumor activity in vivo. These preclinical findings provide mechanistic hypotheses that may be relevant to the improved clinical outcomes observed for enfortumab vedotin plus pembrolizumab relative to chemotherapy.

Author Info: (1) Pfizer, Inc., Bothell, WA 98021, USA. (2) Pfizer, Inc., Bothell, WA 98021, USA. (3) Seagen, Inc., Bothell, WA 98021, USA. (4) Pfizer, Inc., Bothell, WA 98021, USA. (5) Pfizer,

Author Info: (1) Pfizer, Inc., Bothell, WA 98021, USA. (2) Pfizer, Inc., Bothell, WA 98021, USA. (3) Seagen, Inc., Bothell, WA 98021, USA. (4) Pfizer, Inc., Bothell, WA 98021, USA. (5) Pfizer, Inc., Bothell, WA 98021, USA. (6) Pfizer, Inc., Bothell, WA 98021, USA. (7) Pfizer, Inc., Bothell, WA 98021, USA. (8) Seagen, Inc., Bothell, WA 98021, USA. (9) Pfizer, Inc., Bothell, WA 98021, USA. (10) Pfizer, Inc., Bothell, WA 98021, USA. (11) Pfizer, Inc., Bothell, WA 98021, USA. (12) Seagen, Inc., Bothell, WA 98021, USA. (13) Seagen, Inc., Bothell, WA 98021, USA. (14) Pfizer, Inc., Bothell, WA 98021, USA. (15) Pfizer, Inc., Bothell, WA 98021, USA. (16) Seagen, Inc., Bothell, WA 98021, USA. (17) Seagen, Inc., Bothell, WA 98021, USA. (18) Astellas Pharma Inc., Tsukuba, Ibaraki, Japan. (19) Astellas Research Institute of America LLC, Northbrook, IL 60062, USA. (20) Pfizer, Inc., Bothell, WA 98021, USA. (21) Pfizer, Inc., Bothell, WA 98021, USA. (22) Pfizer, Inc., Bothell, WA 98021, USA. Electronic address: sharsti.sandall@pfizer.com.

Neutralizing the IL-12/IL-23 p40 subunit prevents immune checkpoint blockade toxicity without compromising antitumor efficacy Spotlight 

Groeneveldt et al. investigated mechanisms driving early-stage immune-related adverse events (irAEs) in patients with metastatic melanoma treated with combination ICB (anti-PD-1 and anti-CTLA-4). Proteomic analysis of serum identified an early, significant increase of p40, a subunit of IL-12/I-23, prior to the onset of clinically apparent irAEs, which was not associated with ICB efficacy. In mouse models that mimic irAEs in patients, p40 neutralization prevented ICB-induced toxicity, without compromising antitumor T cell immunity, including the establishment of tumor-specific responses, suggesting distinct mechanisms that can be uncoupled.

Contributed by Katherine Turner

Groeneveldt et al. investigated mechanisms driving early-stage immune-related adverse events (irAEs) in patients with metastatic melanoma treated with combination ICB (anti-PD-1 and anti-CTLA-4). Proteomic analysis of serum identified an early, significant increase of p40, a subunit of IL-12/I-23, prior to the onset of clinically apparent irAEs, which was not associated with ICB efficacy. In mouse models that mimic irAEs in patients, p40 neutralization prevented ICB-induced toxicity, without compromising antitumor T cell immunity, including the establishment of tumor-specific responses, suggesting distinct mechanisms that can be uncoupled.

Contributed by Katherine Turner

ABSTRACT: Immune checkpoint blockade (ICB) has markedly improved overall survival in various cancers, but is associated with severe and sometimes fatal immune-related adverse events (irAEs). Current management of irAEs involves discontinuation of ICB therapy and administration of immunosuppressive drugs, such as corticosteroids, which have been associated with decreased antitumor efficacy. Although irAE development is associated with ICB response, it is currently unknown whether their underlying mechanisms are shared or distinct. To identify early and targetable drivers of irAEs, we performed proteomic analyses on the serum of patients with cancer treated with anti-PD-1 and anti-CTLA-4 combination ICB. We identified a significantly increased concentration of p40, a subunit of IL-12/IL-23, shortly after the start of ICB but before the onset of clinically apparent irAEs. Importantly, increased p40 levels were not associated with ICB efficacy. Neutralizing p40 mitigated ICB-induced toxicity in various mouse models without impairing ICB-induced antitumor efficacy. In conclusion, we demonstrated that IL-12/IL-23p40 is a key mediator of ICB-induced toxicity while being redundant for ICB antitumor efficacy. This shows that the mechanisms underlying ICB toxicity and efficacy can be uncoupled and provides a rationale for p40 blockade in clinical trials with ICB treatment to prevent irAEs in patients.

Author Info: (1) Erasmus MC Rotterdam Netherlands. ROR: https://ror.org/018906e22 (2) Erasmus MC Cancer Institute Rotterdam, South-Holland Netherlands. ROR: https://ror.org/03r4m3349 (3) Erasmu

Author Info: (1) Erasmus MC Rotterdam Netherlands. ROR: https://ror.org/018906e22 (2) Erasmus MC Cancer Institute Rotterdam, South-Holland Netherlands. ROR: https://ror.org/03r4m3349 (3) Erasmus MC Netherlands. ROR: https://ror.org/018906e22 (4) Cancer Research UK Scotland Institute United Kingdom. ROR: https://ror.org/03pv69j64 (5) Erasmus MC Cancer Institute Rotterdam Netherlands. ROR: https://ror.org/03r4m3349 (6) Erasmus MC Cancer Institute Netherlands. ROR: https://ror.org/03r4m3349 (7) Erasmus MC Rotterdam Rotterdam Netherlands. (8) Erasmus MC Cancer Institute Netherlands. ROR: https://ror.org/03r4m3349 (9) Erasmus MC Rotterdam Rotterdam Netherlands. (10) Erasmus MC Cancer Institute Rotterdam Netherlands. ROR: https://ror.org/03r4m3349 (11) Erasmus MC Cancer Institute Rotterdam Netherlands. ROR: https://ror.org/03r4m3349 (12) Erasmus MC Rotterdam Netherlands. ROR: https://ror.org/018906e22 (13) University of Warsaw Poland. ROR: https://ror.org/039bjqg32 (14) Erasmus MC Rotterdam Netherlands. ROR: https://ror.org/018906e22 (15) Erasmus MC - Sophia Children's Hospital Rotterdam, South Holland Netherlands. ROR: https://ror.org/047afsm11 (16) Erasmus MC Rotterdam Netherlands. ROR: https://ror.org/018906e22 (17) Erasmus MC Rotterdam Rotterdam Netherlands. (18) Erasmus MC Cancer Institute Rotterdam Netherlands. ROR: https://ror.org/03r4m3349 (19) Erasmus MC Cancer Institute Rotterdam Netherlands. ROR: https://ror.org/03r4m3349

Tumor immune microenvironment remodeling predicts response to checkpoint inhibitor therapy Spotlight 

Lin et al. developed a longitudinal scRNAseq atlas of 441 ICI-treated tumors from 241 patients across 10 cancer types, and identified 4 conserved TIME states. ICI induced temporal TIME remodeling with early T cell activation, resolution of distinct ISG patterns, and progressive stromal and immune restructuring. During treatment, approximately 40% of tumors transitioned between TIME states, with inflamed or B cell-enriched transitions associated with response and survival, while myeloid-dominant states associated with resistance. A baseline 59-gene transition signature was predictive of ICI response and survival across 1,383 tumors from 19 independent cohorts.

Contributed by Shishir Pant

Lin et al. developed a longitudinal scRNAseq atlas of 441 ICI-treated tumors from 241 patients across 10 cancer types, and identified 4 conserved TIME states. ICI induced temporal TIME remodeling with early T cell activation, resolution of distinct ISG patterns, and progressive stromal and immune restructuring. During treatment, approximately 40% of tumors transitioned between TIME states, with inflamed or B cell-enriched transitions associated with response and survival, while myeloid-dominant states associated with resistance. A baseline 59-gene transition signature was predictive of ICI response and survival across 1,383 tumors from 19 independent cohorts.

Contributed by Shishir Pant

ABSTRACT: Immune checkpoint inhibitors (ICIs) have transformed cancer therapy, yet the basis of variable patient responses remains unclear. We assemble a longitudinal single-cell RNA sequencing atlas of 441 samples from 241 patients across ten cancer entities to map treatment-associated remodeling of the tumor immune microenvironment (TIME). With a hierarchical reference-guided deep-phenotyping framework, we define 77 immune and stromal subtypes and resolve four conserved TIME subtypes. Approximately 40% of tumors shift between states during therapy, and the transition is more predictive of outcome than the baseline state. Favorable transitions toward inflamed or B cell-enriched subtype track with improved response and survival, while persistence in or shifts toward myeloid dominance indicate resistance. We derive a 59-gene signature that predicted response and survival for 1,383 baseline tumors across 19 independent cohorts. These findings establish immunotype transitions as a central determinant of ICI efficacy, offering new avenues for response prediction and rational immunotherapy design.

Author Info: (1) Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel. (2) Translational Skin Cancer Research, German Cancer Consortium (DKTK), Partner Site Essen, Medical

Author Info: (1) Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel. (2) Translational Skin Cancer Research, German Cancer Consortium (DKTK), Partner Site Essen, Medical Faculty, University of Duisburg-Essen, Essen, Germany; German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany. (3) Translational Skin Cancer Research, German Cancer Consortium (DKTK), Partner Site Essen, Medical Faculty, University of Duisburg-Essen, Essen, Germany; German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany; Department of Dermatology, University Hospital Essen, Essen, Germany. (4) German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany; Department of Dermatology, University Hospital Essen, Essen, Germany. (5) Translational Skin Cancer Research, German Cancer Consortium (DKTK), Partner Site Essen, Medical Faculty, University of Duisburg-Essen, Essen, Germany; German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany; Department of Dermatology, University Hospital Essen, Essen, Germany. Electronic address: j.becker@dkfz-heidelberg.de. (6) Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel; The Taub Faculty of Computer Science, Technion-Israel Institute of Technology, Haifa, Israel. Electronic address: dviraran@technion.ac.il.

In vivo genome-wide CRISPR screens of human T cells in solid tumours Spotlight 

Liu et al. developed a genome-wide in vivo CRISPR screening platform using a T cell-attracting anti-CD3 scFv-expressing A375 tumor model and primary human T cells to identify in vivo regulators of intratumoral T cell abundance and effector function. The abundance screen identified P2RY8-Gα13 as a negative regulator of T cell tumor infiltration, whereas the IFNγ-based functional screen identified GNAS as a key driver of intratumoral T cell dysfunction. GNAS deletion enhanced CAR- and TCR-T cell fitness and efficacy across solid tumor models. P2RY8 and GNAS dual-knockout CAR T cells showed increased infiltration and improved tumor control.

Contributed by Shishir Pant

Liu et al. developed a genome-wide in vivo CRISPR screening platform using a T cell-attracting anti-CD3 scFv-expressing A375 tumor model and primary human T cells to identify in vivo regulators of intratumoral T cell abundance and effector function. The abundance screen identified P2RY8-Gα13 as a negative regulator of T cell tumor infiltration, whereas the IFNγ-based functional screen identified GNAS as a key driver of intratumoral T cell dysfunction. GNAS deletion enhanced CAR- and TCR-T cell fitness and efficacy across solid tumor models. P2RY8 and GNAS dual-knockout CAR T cells showed increased infiltration and improved tumor control.

Contributed by Shishir Pant

ABSTRACT: Large-scale CRISPR screening in human T cells holds significant promise for identifying genetic modifications that enhance cellular immunotherapy. Yet, many regulators of T cell performance in solid tumours are not revealed in vitro(1,2). In vivo screening in tumour-bearing mice is more physiological but has been limited by low intratumoural T cell recovery. Here we developed an in vivo model that efficiently recovers human T cells from solid tumours, permitting genome-wide CRISPR screens with few mice. Tumour-infiltrating T cells from this model exhibit hallmarks of dysfunction compared with splenic T cells, creating an ideal screening context. We performed two genome-wide CRISPR knockout screens to identify regulators of intratumoural T cell abundance and effector function. The abundance screen revealed the P2RY8-G_13 GPCR signalling axis as a negative regulator of T cell tumour infiltration. The effector function screen identified GNAS as a key driver of T cell dysfunction in tumours, whose product, G_s, acts as a convergent node downstream of multiple GPCRs sensing distinct suppressive ligands. Knockout of GNAS rendered T cells resistant to multiple suppressive cues and significantly improved efficacy across diverse solid tumour models in chimeric antigen receptor (CAR) and T cell receptor (TCR) systems. Combinatorial knockout of P2RY8-GNAS further enhanced tumour control, demonstrating that complementary in vivo screens can identify orthogonal targets whose combined editing improves therapeutic potency. This flexible, scalable platform can be adapted for systematic discovery of genetic strategies to improve solid tumour T cell therapies.

Author Info: (1) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. qi.liu3@ucsf.edu. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA

Author Info: (1) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. qi.liu3@ucsf.edu. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. qi.liu3@ucsf.edu. (2) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (3) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (4) Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (5) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (6) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (7) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (8) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. UCSF CoLabs, University of California San Francisco, San Francisco, CA, USA. Department of Surgery, University of California San Francisco, San Francisco, CA, USA. Diabetes Center, University of California San Francisco, San Francisco, CA, USA. (9) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (10) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (11) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (12) Department of Microbiology and Immunology and Howard Hughes Medical Institute, University of California San Francisco, San Francisco, CA, USA. (13) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (14) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (15) Department of Microbiology and Immunology and Howard Hughes Medical Institute, University of California San Francisco, San Francisco, CA, USA. Division of Pediatric Rheumatology, Department of Pediatrics, University of California San Francisco, San Francisco, CA, USA. (16) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. (17) Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (18) Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA. (19) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (20) Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA. (21) Division of Oncology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA. (22) Division of Immunology and Rheumatology, Department of Medicine, Stanford University, Stanford, CA, USA. Division of Computational Medicine, Department of Medicine, Stanford University, Stanford, CA, USA. (23) Division of Immunology and Rheumatology, Department of Medicine, Stanford University, Stanford, CA, USA. Division of Computational Medicine, Department of Medicine, Stanford University, Stanford, CA, USA. Parker Institute for Cancer Immunotherapy, San Francisco, CA, USA. Weill Cancer Hub West, Stanford University and University of California, San Francisco, CA, USA. (24) Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. Weill Cancer Hub West, Stanford University and University of California, San Francisco, CA, USA. Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA. UCSF Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA. (25) Gray Faculty of Medical and Health Sciences, Tel Aviv University, Tel Aviv, Israel. George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel. Dotan Center for Advanced Therapies, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel. (26) Weill Cancer Hub West, Stanford University and University of California, San Francisco, CA, USA. Department of Pathology, University of California San Francisco, San Francisco, CA, USA. (27) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Parker Institute for Cancer Immunotherapy, San Francisco, CA, USA. Weill Cancer Hub West, Stanford University and University of California, San Francisco, CA, USA. UCSF Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA. (28) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. Parker Institute for Cancer Immunotherapy, San Francisco, CA, USA. Weill Cancer Hub West, Stanford University and University of California, San Francisco, CA, USA. (29) Department of OB/Gyn, Center for Reproductive Sciences, University of California San Francisco, San Francisco, CA, USA. (30) Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. (31) Department of Microbiology and Immunology and Howard Hughes Medical Institute, University of California San Francisco, San Francisco, CA, USA. (32) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. Parker Institute for Cancer Immunotherapy, San Francisco, CA, USA. Weill Cancer Hub West, Stanford University and University of California, San Francisco, CA, USA. UCSF Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA. Institute for Human Genetics (IHG), University of California San Francisco, San Francisco, CA, USA. Department of Microbiology and Immunology, University of California San Francisco, San Francisco, CA, USA. Innovative Genomics Institute, University of California Berkeley, Berkeley, CA, USA. (33) Department of Medicine, University of California San Francisco, San Francisco, CA, USA. julia.carnevale@ucsf.edu. Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA. julia.carnevale@ucsf.edu. Parker Institute for Cancer Immunotherapy, San Francisco, CA, USA. julia.carnevale@ucsf.edu. Weill Cancer Hub West, Stanford University and University of California, San Francisco, CA, USA. julia.carnevale@ucsf.edu. UCSF Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA. julia.carnevale@ucsf.edu.

Scalable generation of hematopoietic stem cell-engineered off-the-shelf mono-specific cytotoxic T cells targeting solid tumors Spotlight 

Zhu and Yu et al. developed and characterized a scalable, feeder-free, high-yield platform that generated allogeneic NY-ESO-1-specific cytotoxic T (AlloESO-T) cells from cord blood-derived hematopoietic stem and progenitor cells. Compared to PBMC-derived TCR-T cells, monospecific AlloESO-T cells showed superior cytotoxicity (with dual TCR and NKR targeting), solid tumor homing, HLA-independence, durable killing persistence (with IL-15), and enhanced efficacy in solid tumor models. AlloESO-T cells, which lack endogenous TCRs, exhibited an improved safety profile and minimal GvHD or /cytokine release syndrome risk in vitro and in vivo.

Contributed by Katherine Turner

Zhu and Yu et al. developed and characterized a scalable, feeder-free, high-yield platform that generated allogeneic NY-ESO-1-specific cytotoxic T (AlloESO-T) cells from cord blood-derived hematopoietic stem and progenitor cells. Compared to PBMC-derived TCR-T cells, monospecific AlloESO-T cells showed superior cytotoxicity (with dual TCR and NKR targeting), solid tumor homing, HLA-independence, durable killing persistence (with IL-15), and enhanced efficacy in solid tumor models. AlloESO-T cells, which lack endogenous TCRs, exhibited an improved safety profile and minimal GvHD or /cytokine release syndrome risk in vitro and in vivo.

Contributed by Katherine Turner

ABSTRACT: Adoptive T cell therapy for solid tumors is limited by autologous manufacturing complexity and, in allogeneic settings, risks including graft-versus-host disease (GvHD), HLA restriction, and donor variability. We develop a scalable, feeder-free platform to differentiate gene-engineered hematopoietic stem and progenitor cells (HSPCs) into allogeneic, NY-ESO-1-specific cytotoxic T ((Allo)ESO-T) cells. Product phenotype, function, tumor homing, and safety are assessed against solid tumor models and benchmarked to peripheral blood mononuclear cell (PBMC)-derived TCR-engineered T cells. (Allo)ESO-T cells display a uniform cytotoxic phenotype, with dual tumor targeting through a transgenic TCR and natural killer receptors. Relative to PBMC-derived counterparts, (Allo)ESO-T cells show superior cytotoxicity, selective solid-tumor homing, durable killing persistence, and resilience to immune evasion. They also maintain low GvHD and cytokine release syndrome risk, while retaining stable hypoimmunogenic features. These findings establish HSPC-derived (Allo)ESO-T cells as an off-the-shelf, mono-specific cytotoxic T cell therapy with scalable manufacturing, enhanced efficacy, and improved safety, which support broad applicability of (Allo)ESO-T cells across solid tumors.

Author Info: (1) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los A

Author Info: (1) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (2) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (3) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (4) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (5) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (6) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (7) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (8) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (9) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (10) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (11) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (12) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (13) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (14) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (15) Department of Medicine, Division of Cardiology, UCLA, Los Angeles, CA 90095, USA. (16) Department of Biomedical Engineering, University of California, Davis, Davis, CA 95616, USA. (17) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (18) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (19) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. (20) Department of Biomedical Engineering, University of California, Davis, Davis, CA 95616, USA. (21) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA. Electronic address: charlie.li@ucla.edu. (22) Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA; Department of Bioengineering, UCLA, Los Angeles, CA 90095, USA; Eli and Edythe Broad Centre of Regenerative Medicine and Stem Cell Research, UCLA, Los Angeles, CA 90095, USA; Jonsson Comprehensive Cancer Center, UCLA, Los Angeles, CA 90095, USA; Molecular Biology Institute, UCLA, Los Angeles, CA 90095, USA; Parker Institute for Cancer Immunotherapy, UCLA, Los Angeles, CA 90095, USA; Goodman-Luskin Microbiome Center, UCLA, Los Angeles, CA 90095, USA. Electronic address: liliyang@ucla.edu.

Synthetic transcription factors designed by domain recombination enhance CAR T cell antitumor function Spotlight 

Takacsi-Nagy et al. generated a library of synthetic T cell Transcription Factors (sTFs) through combinatorial assembly of AP-1 family TF subdomains. Expressed in CAR-T cells, certain sTFs improved CAR-T persistence/proliferation over natural TFs in a chronic stimulation assay. sTFs induced unique transcriptional and epigenetic T cell states from natural TFs, although their DNA binding sites were conserved. One combination (JUN-FOS-BATF) especially improved cytotoxicity and in vivo persistence. The most impactful subdomains did not correlate with natural expression levels. Recombination of ETS and FOX family TF domains was also effective.

Contributed by Alex Najibi

Takacsi-Nagy et al. generated a library of synthetic T cell Transcription Factors (sTFs) through combinatorial assembly of AP-1 family TF subdomains. Expressed in CAR-T cells, certain sTFs improved CAR-T persistence/proliferation over natural TFs in a chronic stimulation assay. sTFs induced unique transcriptional and epigenetic T cell states from natural TFs, although their DNA binding sites were conserved. One combination (JUN-FOS-BATF) especially improved cytotoxicity and in vivo persistence. The most impactful subdomains did not correlate with natural expression levels. Recombination of ETS and FOX family TF domains was also effective.

Contributed by Alex Najibi

ABSTRACT: Human protein-coding genes evolved via rearrangement of domains from ancestral genes. We develop a scalable, evolutionarily guided method to assemble novel genes from constituent domains within a protein family, termed DESynR (domain engineered via synthesis and recombination) genes. In primary human T cells, DESynR activator protein-1 (AP-1) transcription factors (TFs) significantly outperform natural AP-1 TFs across in vitro and in vivo antitumor assays. DESynR AP-1 TFs induce broad transcriptional and epigenetic reprogramming and establish non-natural T cell states that optimize features of exhaustion, effector and cytotoxic function, and persistence-sometimes co-opting gene modules from disparate cell types. Reprogramming is primarily driven by differential regulation of established AP-1-bound regulatory elements rather than unique binding. Finally, we screen DESynR erythroblast transformation-specific (ETS) and forkhead box (FOX) TFs to support generalizability across protein families. Overall, we demonstrate that reconfiguring existing protein domains may uncover non-evolved genes that program therapeutically relevant cell states.

Author Info: (1) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA; Program in Immunology, Stanford Univer

Author Info: (1) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA; Program in Immunology, Stanford University, Stanford, CA, USA. (2) Center for Immunotherapy Design, Stanford University, Stanford, CA, USA; Division of Allergy, Immunology, and Rheumatology, Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, USA. (3) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA; Department of Genetics, Stanford University, Stanford, CA, USA. (4) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA. (5) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA. (6) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA; Department of Bioengineering, Stanford University, Stanford, CA, USA. (7) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA. (8) Program in Immunology, Stanford University, Stanford, CA, USA; Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA; Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA. (9) Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA; Department of Medicine, University of California, San Francisco, San Francisco, CA, USA; Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, USA. (10) Department of Pathology, Stanford University, Stanford, CA, USA. (11) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA. (12) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA. (13) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA. (14) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA; Program in Immunology, Stanford University, Stanford, CA, USA. (15) Department of Pathology, Stanford University, Stanford, CA, USA. (16) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA. (17) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA; Program in Immunology, Stanford University, Stanford, CA, USA. (18) Center for Cancer Cell Therapy, Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA. (19) Center for Cancer Cell Therapy, Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA; Weill Cancer Hub West, Stanford, CA, USA. (20) Gladstone-UCSF Institute of Genomic Immunology, San Francisco, CA, USA; Department of Medicine, University of California, San Francisco, San Francisco, CA, USA; Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA, USA; Parker Institute for Cancer Immunotherapy, San Francisco, CA, USA; Weill Cancer Hub West, Stanford, CA, USA. (21) Parker Institute for Cancer Immunotherapy, San Francisco, CA, USA; Center for Cancer Cell Therapy, Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA; Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA; Department of Pediatrics, Stanford University School of Medicine, Stanford, CA, USA; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA, USA; Ludwig Center for Cancer Stem Cell Research and Medicine, Stanford University School of Medicine, Stanford, CA, USA; Weill Cancer Hub West, Stanford, CA, USA. (22) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA; Parker Institute for Cancer Immunotherapy, San Francisco, CA, USA; Weill Cancer Hub West, Stanford, CA, USA. Electronic address: troth@stanford.edu. (23) Department of Pathology, Stanford University, Stanford, CA, USA; Center for Immunotherapy Design, Stanford University, Stanford, CA, USA; Program in Immunology, Stanford University, Stanford, CA, USA; Parker Institute for Cancer Immunotherapy, San Francisco, CA, USA; Weill Cancer Hub West, Stanford, CA, USA. Electronic address: satpathy@stanford.edu.

SYS6010, epidermal growth factor receptor-targeting antibody-drug conjugate for advanced non-small cell lung cancer: A phase 1 trial Spotlight 

In a phase 1 trial, Li and Zhou et al. evaluated the EGFR-targeting, topoisomerase I inhibitor JS-1-carrying ADC SYS6010 in 236 patients with previously treated, advanced NSCLC (diverse subtypes and EGFR status). One dose-limiting toxicity was observed (thrombocytopenia), and a recommended phase 2 dose was established. Treatment-related adverse events of all grades and grade ≥3 (mainly hematological) occurred in 99.6% and 57.2% of patients, respectively. Encouraging clinical activity was observed across disease types, irrespective of EGFR mutation status, and correlated with EGFR expression levels.

Contributed by Ute Burkhardt

In a phase 1 trial, Li and Zhou et al. evaluated the EGFR-targeting, topoisomerase I inhibitor JS-1-carrying ADC SYS6010 in 236 patients with previously treated, advanced NSCLC (diverse subtypes and EGFR status). One dose-limiting toxicity was observed (thrombocytopenia), and a recommended phase 2 dose was established. Treatment-related adverse events of all grades and grade ≥3 (mainly hematological) occurred in 99.6% and 57.2% of patients, respectively. Encouraging clinical activity was observed across disease types, irrespective of EGFR mutation status, and correlated with EGFR expression levels.

Contributed by Ute Burkhardt

ABSTRACT: SYS6010 is an antibody-drug conjugate targeting epidermal growth factor receptor (EGFR). We report the results of a phase 1 trial (ChiCTR2300072141) of SYS6010 in patients with non-small cell lung cancer (NSCLC). A total of 236 patients were treated. One dose-limiting toxicity occurred at 6.4 mg/kg; therefore, 4.2, 4.5, and 4.8 mg/kg were selected for cohort expansion. Treatment-related adverse events (TRAEs; any/grade ³ 3) occurred in 99.6%/57.2% of patients. Common grade ³3 TRAEs included neutropenia (30.9%), leukopenia (25.0%), and thrombocytopenia (17.4%). Objective response rate was 34.7% in EGFR-mutant NSCLC treated with EGFR tyrosine kinase inhibitors (TKIs) and platinum chemotherapy, 45.7% in EGFR-mutant NSCLC treated with EGFR TKIs, 20.0% in EGFR wild-type squamous NSCLC, and 35.7% in EGFR wild-type non-squamous NSCLC. Median progression-free survival and overall survival were 7.6 and 19.4 months, respectively, in EGFR-mutant NSCLC treated with EGFR TKIs and platinum chemotherapy. Overall, SYS6010 shows a manageable safety profile and encouraging antitumor activity in previously treated, advanced NSCLC.

Author Info: (1) Department of Medical Oncology, Shanghai Chest Hospital, Shanghai Jiaotong University, School of Medicine, Shanghai Key Laboratory of Thoracic Tumor Biotherapy, Shanghai 200030

Author Info: (1) Department of Medical Oncology, Shanghai Chest Hospital, Shanghai Jiaotong University, School of Medicine, Shanghai Key Laboratory of Thoracic Tumor Biotherapy, Shanghai 200030, P.R. China. (2) Department of Medical Oncology, Shanghai Chest Hospital, Shanghai Jiaotong University, School of Medicine, Shanghai Key Laboratory of Thoracic Tumor Biotherapy, Shanghai 200030, P.R. China. (3) Department of Thoracic Oncology, Fujian Provincial Cancer Hospital, Fuzhou 350014, P.R. China. (4) Department of Oncology, Xuzhou Center Hospital, Xuzhou 221000, P.R. China. (5) Department of Thoracic Oncology II, Beijing Cancer Hospital, Beijing 100142, P.R. China. (6) Department of Medical Oncology, Jiamusi Tumor Hospital, Jiamusi 154000 P.R. China. (7) Department of Critical Care Medicine, Jilin Cancer Hospital, Changchun 130000 P.R. China. (8) Clinical Pharmacology and Medical Department, The Fourth Hospital of Hebei Medical University, Shijiazhuang 050000, P.R. China. (9) Department of Medical Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang 050000, P.R. China. (10) Department of Medical Oncology, The First Affiliated Hospital of China Medical University, Shenyang 110000, P.R. China. (11) Department of Oncology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an 710061, P.R. China. (12) Phase I Ward, Chongqing University Cancer Hospital, Chongqing 400030, P.R. China. (13) Respiratory Medicine Ward 3, Cancer Hospital Affiliated to Harbin Medical University, Harbin 150000, P.R. China. (14) Department of Oncology, First Affiliated Hospital of Gannan Medical University, Ganzhou 341001, P.R. China. (15) Department of Medical Oncology, National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021, P.R. China. (16) Continuity of Care Unit, Shanghai Pulmonary Hospital, Shanghai 200433, P.R. China. (17) Department of Oro-maxillofacial Head and Neck Oncology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430048, P.R. China. (18) Department of Medical Oncology, Affiliated Hospital of Hebei University, Baoding 071000, P.R. China. (19) Department of Medical Oncology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, P.R. China. (20) Department of Medical Oncology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, P.R. China. (21) Department of Oncology, The Second Affiliated Hospital of Anhui Medical University, Hefei 230601, P.R. China. (22) Department of Thoracic Tumor Radiotherapy, Jiangxi Cancer Hospital, Nanchang 330029 P.R. China. (23) Department of Oncology, The First Hospital of Jilin University, Changchun 130021, P.R. China. (24) Department of Medical Oncology, Fujian Medical University Union Hospital, Fuzhou 350001, P.R. China. (25) Department of Oncology, Army Medical Center with Distinctive Features, Chongqing, 400010, P.R. China. (26) Department of Oncology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou 310000, P.R. China. (27) Department of Internal Medicine No.2, Yunnan Cancer Hospital, Kunming 650106, P.R. China. (28) Department of Oncology, The First Affiliated Hospital with Nanjing Medical University, Nanjing 210029, P.R. China. (29) Department of Oncology, The First Affiliated Hospital of Guangdong Pharmaceutical University, Guangzhou 510080, P.R. China. (30) Preclinical Division, CSPC Pharmaceutical Group Co., Ltd, Shijiazhuang 050035, P.R. China. (31) Clinical Development Division, CSPC Pharmaceutical Group Co., Ltd, Shijiazhuang 050035, P.R. China. (32) Clinical Development Division, CSPC Pharmaceutical Group Co., Ltd, Shijiazhuang 050035, P.R. China. (33) Clinical Development Division, CSPC Pharmaceutical Group Co., Ltd, Shijiazhuang 050035, P.R. China. (34) Clinical Development Division, CSPC Pharmaceutical Group Co., Ltd, Shijiazhuang 050035, P.R. China. (35) Clinical Development Division, CSPC Pharmaceutical Group Co., Ltd, Shijiazhuang 050035, P.R. China. (36) Department of Medical Oncology, Shanghai Chest Hospital, Shanghai Jiaotong University, School of Medicine, Shanghai Key Laboratory of Thoracic Tumor Biotherapy, Shanghai 200030, P.R. China. Electronic address: shunlu@sjtu.edu.cn.

UV irradiation drives lineage-specific MITF-mediated transcription of PD-L1 to confer immune tolerance to UV-mutated melanocytes Featured  

Lo et al. found that in melanocytes, MITF mediates upregulation of PD-L1 by binding to an enhancer, inducing high baseline PD-L1 that is further upregulated upon exposure to UVR. This mechanism has a tolerogenic effect, protecting melanocytes from immune-mediated elimination, even after the accumulation of UV-induced mutations. While this mechanism did not appear to play a major role in immune-hot melanomas with high IFNγ expression, it did show an effect in less infiltrated melanomas, and could contribute to their development.

Lo et al. found that in melanocytes, MITF mediates upregulation of PD-L1 by binding to an enhancer, inducing high baseline PD-L1 that is further upregulated upon exposure to UVR. This mechanism has a tolerogenic effect, protecting melanocytes from immune-mediated elimination, even after the accumulation of UV-induced mutations. While this mechanism did not appear to play a major role in immune-hot melanomas with high IFNγ expression, it did show an effect in less infiltrated melanomas, and could contribute to their development.

ABSTRACT: UV radiation (UVR) drives high mutational burdens, yet precursor melanocytes accumulate these mutations without triggering immune clearance. Here, we investigated whether melanocyte-intrinsic transcriptional program(s) underlie immune tolerance to mutations resulting from UVR exposure. In primary human melanocytes, expression of PD-L1 (CD274) was dependent on microphthalmia-associated transcription factor (MITF), a crucial regulator of melanocyte development and an intermediate in the UV-tanning pathway. MITF directly activated PD-L1 transcription by binding a conserved upstream enhancer containing functional E-box elements. MITF determined both baseline melanocytic PD-L1 expression in healthy skin and its induction following UVR, independent of interferon signaling. Melanocyte-restricted Pd-l1 deletion in mice triggered CD8(+) T cell infiltration and depigmentation after long-term UVB exposure, recapitulating features of human vitiligo. PD-L1-deficient human induced pluripotent stem cell (iPSC)-derived melanocytes underwent increased apoptosis and were more susceptible than PD-L1-intact melanocytes to gp100-specific CD8(+) T cell killing. Thus, a melanocyte-intrinsic MITF-PD-L1 tolerance program protects melanocytes from autoimmune destruction, potentially facilitating early immune evasion during melanoma development and conversely underlying the responsiveness of melanoma to PD-1/PD-L1 blockade.

Author Info: (1) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA; Department of Dermatology, Beth

Author Info: (1) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA; Department of Dermatology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA 02215, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA. (2) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. (3) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. (4) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. (5) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA; Department of Dermatology, Kyoto University Graduate School of Medicine, Sakyo-ku, Kyoto 606-8507, Japan. (6) Department of Physics, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA. (7) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. (8) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. (9) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. (10) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA; Department of Stomatology, Central Hospital Affiliated to Shandong First Medical University, Jinan 250013, Shandong, China. (11) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. (12) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA; HCEMM-SU Translational Dermatology Research Group, Semmelweis University, Budapest 1085, Hungary; Department of Physiology, Faculty of Medicine, Semmelweis University, Budapest 1094, Hungary; Department of Dermatology, Venereology and Dermatooncology, Faculty of Medicine, Semmelweis University, Budapest 1085, Hungary; MTA-SE LendŸlet "Momentum" Dermatology Research Group, Hungarian Academy of Sciences and Semmelweis University, Budapest 1085, Hungary. (13) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. (14) Department of Dermatology, University of California, San Francisco, San Francisco, CA 94143, USA; Dermatology Service, San Francisco Veterans Administration Health Care System, San Francisco, CA 94121, USA. (15) Lautenberg Center for Immunology and Cancer Research, The Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem 91120, Israel; Center for Melanoma and Cancer Immunotherapy, Sharett Institute of Oncology, Jerusalem 91120, Israel; Hadassah Cancer Research Institute, Hadassah Hebrew University Medical Center, Jerusalem 91120, Israel. (16) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. (17) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. (18) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA; Department of Dermatology, University Hospital of Basel, 4031 Basel, Switzerland. (19) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA; Department of Dermatology, University of Utah, Salt Lake City, UT 84132, USA. (20) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. (21) Department of Melanoma Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA. (22) IStem, CECS, Corbeil-Essonnes 91100, France. (23) UniversitŽ Paris-Saclay, UniversitŽ d'Evry, Inserm, IStem, UMR861, Corbeil-Essonnes 91100, France. (24) UniversitŽ Paris-Saclay, UniversitŽ d'Evry, Inserm, IStem, UMR861, Corbeil-Essonnes 91100, France. (25) UniversitŽ Paris-Saclay, UniversitŽ d'Evry, Inserm, IStem, UMR861, Corbeil-Essonnes 91100, France. (26) UniversitŽ Paris-Saclay, UniversitŽ d'Evry, Inserm, IStem, UMR861, Corbeil-Essonnes 91100, France. (27) Department of Medical Oncology, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, Boston, MA 02215, USA. (28) Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Center for Cancer Research, Massachusetts General Hospital, Boston, MA 02142, USA. (29) Mass General Brigham Cancer Institute, Boston, MA 02114, USA. (30) Department of Surgery, Massachusetts General Hospital, Boston, MA 02114, USA; Krantz Family Center for Cancer Research, Massachusetts General Hospital, Boston, MA 02114, USA. (31) Department of Physics, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA. (32) Department of Immunology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA; Gene Lay Institute of Immunology and Inflammation of Brigham and Women's Hospital, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02115, USA. (33) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. (34) Department of Melanoma Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Department of Immunology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA; Parker Institute of Cancer Immunotherapy, San Francisco, CA 94129, USA. (35) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA; UniversitŽ Paris-Saclay, UniversitŽ d'Evry, Inserm, IStem, UMR861, Corbeil-Essonnes 91100, France. Electronic address: jeallouche@gmail.com. (36) Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02129, USA. Electronic address: dfisher3@mgh.harvard.edu.

CAR T Cells Targeting O-Glycosylated Fibronectin Exhibit Potent Cytolytic Activity and Combine with Tumoral Toll-Like Receptor Agonism to Overcome Tumor Resistance Spotlight 

King-Peoples et al. assessed the Tn-glycosylated IIICS domain of fibronectin (Tn-FN) as an ECM-derived CAR target, and generated FDC6-BBζ CAR T cells using the FDC6 mAb. FDC6-BBζ CAR T cells recognized and lysed PC3 targets in an antigen-dependent manner in vitro, and showed durable tumor control, increased intratumoral CD3+ infiltration, and reduced tumor-collagen overlap in NSG PC3 xenografts. FDC6-BBζ CAR-mediated in vitro cytotoxicity against PC3 was dependent on IFNγR1 signaling, but was Fas-independent. TLR2/6 or TLR4 agonists restored FDC6-BBζ killing of IFNγR1-deficient targets via caspase/NLRP3 inflammasome activity.

Contributed by Shishir Pant

King-Peoples et al. assessed the Tn-glycosylated IIICS domain of fibronectin (Tn-FN) as an ECM-derived CAR target, and generated FDC6-BBζ CAR T cells using the FDC6 mAb. FDC6-BBζ CAR T cells recognized and lysed PC3 targets in an antigen-dependent manner in vitro, and showed durable tumor control, increased intratumoral CD3+ infiltration, and reduced tumor-collagen overlap in NSG PC3 xenografts. FDC6-BBζ CAR-mediated in vitro cytotoxicity against PC3 was dependent on IFNγR1 signaling, but was Fas-independent. TLR2/6 or TLR4 agonists restored FDC6-BBζ killing of IFNγR1-deficient targets via caspase/NLRP3 inflammasome activity.

Contributed by Shishir Pant

ABSTRACT: Tumors remodel extracellular matrix (ECM) and glycosylation, yielding epitopes with restricted or limited detectability in normal adult tissues. Here, we evaluated the O-glycosylated IIICS domain of fibronectin (Tn-FN) as a chimeric antigen receptor (CAR) T cell target. FDC6-BBζ CAR T cells recognizing Tn-FN were benchmarked against EDB-FN-targeted L19-BBζ and Tn-MUC1-targeted 5E5-BBζ. FDC6-BBζ mediated robust, antigen-dependent activation and cytotoxicity, outperforming L19-BBζ and matching 5E5-BBζ in vitro and in NSG xenografts of prostate cancer. FDC6-BBζ and 5E5-BBζ CAR T cells achieved durable tumor control with increased intratumoral CD3⁺ infiltration and reduced tumor-collagen overlap. Cytotoxicity required intact tumor interferon-γ (IFNγ) receptor 1; L19-BBζ further depended on Fas, whereas FDC6-BBζ and 5E5-BBζ were less Fas-dependent. Tumoral toll-like receptor (TLR) 2/6 or TLR4 agonism restored FDC6-BBζ killing of IFNγR1-deficient targets and induced broad inflammatory and stress-response programs. Pharmacologic perturbation implicated caspase-dependent mechanisms and a contribution from inflammasome-linked signaling, whereas ferroptosis blockade did not abrogate restored killing. These findings establish Tn-FN as a glycoform-restricted, ECM-derived CAR target and show that innate agonists can reprogram tumor state to overcome resistance from impaired IFNγ signaling.

Author Info: (1) University of Pennsylvania Philadelphia, PA United States. ROR: https://ror.org/00b30xv10 (2) University of Pennsylvania United States. ROR: https://ror.org/00b30xv10 (3) Unive

Author Info: (1) University of Pennsylvania Philadelphia, PA United States. ROR: https://ror.org/00b30xv10 (2) University of Pennsylvania United States. ROR: https://ror.org/00b30xv10 (3) University of Pennsylvania Philadelphia, Pennsylvania United States. ROR: https://ror.org/00b30xv10 (4) University of Pennsylvania Philadelphia, Pennsylvania United States. ROR: https://ror.org/00b30xv10 (5) University of Pennsylvania United States. ROR: https://ror.org/00b30xv10 (6) University of Pennsylvania United States. ROR: https://ror.org/00b30xv10 (7) University of Pennsylvania Philadelphia United States. ROR: https://ror.org/00b30xv10 (8) University of Pennsylvania United States. ROR: https://ror.org/00b30xv10 (9) University of Pennsylvania United States. ROR: https://ror.org/00b30xv10 (10) University of Pennsylvania Philadelphia, PA United States. ROR: https://ror.org/00b30xv10 (11) Hospital of the University of Pennsylvania Philadelphia, PA United States. ROR: https://ror.org/02917wp91 (12) University of Pennsylvania Philadelphia, PA United States. ROR: https://ror.org/00b30xv10

Close Modal

Small change for you. Big change for us!

This Thanksgiving season, show your support for cancer research by donating your change.

In less than a minute, link your credit card with our partner RoundUp App.

Every purchase you make with that card will be rounded up and the change will be donated to ACIR.

All transactions are securely made through Stripe.