Oncology
Abstract
BACKGROUND. Checkpoint inhibitor-associated autoimmune diabetes (CIADM) is a rare but life-altering complication of immune checkpoint inhibitor (ICI) therapy. Biomarkers that predict type 1 diabetes (T1D) are unreliable for CIADM. AIM. To identify biomarkers for prediction of CIADM. METHODS. From our prospective biobank, 14 CIADM patients who had metastatic melanoma treated with anti-PD-1 ± anti-CTLA4 were identified. Controls were selected from the same biobank, matched 2:1. Pre-treatment, on-ICI and post-CIADM serum and peripheral blood mononuclear cells (PBMCs) were analysed. Serum was analysed for T1D autoantibodies, C-peptide, glucose and cytokines. PBMCs were profiled using flow cytometry. Pancreatic volume was measured using CT volumetry. RESUTLS. Before treatment, CIADM patients had smaller pancreatic volume (27% reduction, p=0.044) and higher anti-GAD antibody titres (median 2.9 versus 0, p=0.01). They had significantly higher baseline proportions of Th17 helper cells (p=0.03), higher CD4+ central memory cells (p=0.04) and lower naïve CD4+ cells (p=0.01). With ICI treatment, greater declines in pancreatic volume were seen in CIADM patients (p<0.0001). Activated CD4+ subsets increased significantly in CIADM and controls with immune-related adverse effects (IRAE) but not controls without IRAE. Using only pre-treatment results, pancreatic volume, anti-GAD antibody titre and baseline immune flow profile were highly predictive of CIADM development, with an area under the curve (AUC) of >0.96. CONCLUSIONS. People who develop CIADM are immunologically predisposed and have antecedent pancreatic and immunological changes that accurately predict disease with excellent sensitivity. These biomarkers could be used to guide ICI use, particularly when planning treatment for low-risk tumours. FUNDING. JEG is supported by NHMRC Investigator grant 2033228. AMM by NHMRC Investigator grant 2009476 and GVL by NHMRC Investigator grant 2007839.
Authors
Linda Wu, John M. Wentworth, Christopher Liddle, Nicole Fewings, Matteo Carlino, David A. Brown, Roderick Clifton-Bligh, Georgina V. Long, Richard A. Scolyer, Nicholas Norris, Sarah C. Sasson, Venessa H.M. Tsang, Alexander M. Menzies, Jenny E. Gunton
Abstract
While immune checkpoint blockade (ICB) therapy has revolutionized the antitumor therapeutic landscape, it remains successful in only a small subset of cancer patients. Poor or loss of MHC-I expression has been implicated as a common mechanism of ICB resistance. Yet the molecular mechanisms underlying impaired MHC-I remain to be fully elucidated. Herein, we identified USP22 as a critical factor responsible for ICB resistance through suppressing MHC-I-mediated neoantigen presentation to CD8 T cells. Both genetic and pharmacologic USP22 inhibition increased immunogenicity and overcome anti-PD-1 immunotherapeutic resistance. At the molecular level, USP22 functions as a deubiquitinase for the methyltransferase EZH2, leading to transcriptional silencing of MHC-I gene expression. Targeted Usp22 inhibition resulted in increased tumoral MHC-I expression and consequently enhanced CD8 T cell killing, which was largely abrogated by Ezh2 reconstitution. Multiplexed immunofluorescence staining detected a strong reverse correlation between USP22 expression and both 2M expression and CD8+ T lymphocyte infiltration in solid tumors. Importantly, USP22 upregulation was associated with ICB immunotherapeutic resistance in patients with lung cancer. Collectively, this study highlights the role of USP22 as a diagnostic biomarker for ICB resistance and provides a potential therapeutic avenue to overcome the current ICB resistance through inhibition of USP22.
Authors
Kun Liu, Radhika Iyer, Yi Li, Jun Zhu, Zhaomeng Cai, Juncheng Wei, Yang Cheng, Amy Tang, Hai Wang, Qiong Gao, Nikita Lavanya Mani, Noah Marx, Beixue Gao, D. Martin Watterson, Seema A. Khan, William J. Gradishar, Huiping Liu, Deyu Fang
Abstract
N6-methyladenosine (m6A), the most predominant RNA modification in humans, participates in various fundamental and pathological bioprocesses. Dynamic manipulation of m6A deposition in the transcriptome is critical for cancer progression, while how this regulation is achieved remains understudied. Here, we report that in prostate cancer (PCa), Polycomb group (PcG) protein Enhancer of Zeste Homolog 2 (EZH2) exerts an additional function in m6A regulation via its enzymatic activity. Mechanistically, EZH2 methylates and stabilizes FOXA1 proteins from degradation, which in turn facilitates the transcription of m6A reader YTHDF1. Through activating an m6A autoregulation pathway, YTHDF1 enhances the translation of METTL14 and WTAP, two critical components of the m6A methyltransferase complex (MTC), and thereby upregulates the global m6A level in PCa cells. We further demonstrate that inhibiting the catalytic activity of EZH2 suppresses the translation process globally through targeting the YTHDF1-m6A axis. By disrupting both the expression and interaction of key m6A MTC subunits, combinational treatment of EZH2 degrader MS8815 and m6A inhibitor STM2457 mitigates prostate tumor growth synergistically. Together, our study decodes a previously hidden interrelationship between EZH2 and mRNA modification, which may be leveraged to advance the EZH2-targeting curative strategies in cancer.
Authors
Yang Yi, Joshua Fry, Chaehyun Yum, Rui Wang, Siqi Wu, Sharath Narayan, Qi Liu, Xingxing Zhang, Htoo Zarni Oo, Ning Xie, Yanqiang Li, Xinlei Gao, Xufen Yu, Xiaoping Hu, Qiaqia Li, Kemal Keseroglu, Ertuğrul M. Özbudak, Sarki A. Abdulkadir, Kaifu Chen, Jian Jin, Jonathan C. Zhao, Xuesen Dong, Daniel Arango, Rendong Yang, Qi Cao
Abstract
Resistance to genotoxic therapies remains a major contributor to tumor recurrence and treatment failure, yet the mechanisms by which cancer cells escape these therapies through DNA damage response (DDR) activation are not fully understood. Here, we identify a DDR regulatory pathway in which glycogen synthase kinase 3 β (GSK3B), a multifunctional serine/threonine kinase, governs DNA double-strand break (DSB) repair pathway choice by phosphorylating 53BP1 at threonine 334 (T334) — a site distinct from canonical ATM targets. This phosphorylation event disrupts 53BP1’s interaction with nonhomologous end joining (NHEJ) effectors PTIP and RIF1, promoting their dissociation from DSBs and inhibiting 53BP1-driven NHEJ. Simultaneously, T334 phosphorylation facilitates the recruitment of CtIP and RPA32 for DNA end resection and promotes homologous recombination (HR) by enabling BRCA1 and RAD51 loading. Notably, the phospho-deficient T334A mutant of 53BP1, unlike 53BP1 loss, accumulates aberrantly at DSBs along with PTIP/RIF1, impairs end resection, and suppresses HR activity. Importantly, both genetic and pharmacologic disruption of the GSK3B–53BP1 axis sensitizes tumors to PARP inhibitors (PARPi) independently of BRCA1 status. Together, these findings reveal a GSK3B-dependent mechanism that regulates DSB repair pathway choice and provide a rationale for targeting this axis to enhance PARPi efficacy in solid tumors regardless of BRCA1 status.
Authors
Heba S. Allam, Scarlett Acklin-Wehnert, Ratan Sadhukhan, Mousumi Patra, Fen Xia
Abstract
Macrophage-mediated phagocytosis plays a critical role in the elimination of cancer cells and shaping antitumor immunity. However, the tumor-intrinsic pathways that regulate cancer cell sensitivity to macrophage-mediated phagocytosis remain poorly defined. In this study, we performed a genome-wide CRISPR screen in murine pancreatic cancer cells cocultured with primary macrophages and identified that disruption of the tumor-intrinsic pyrimidine synthesis pathway enhances phagocytosis. Mechanistically, we discovered that macrophages inhibit the pyrimidine salvage pathway in tumor cells by upregulating Upp1-mediated uridine degradation through cytokines TNF-α and IL-1. This shift increased tumor cells’ reliance on de novo pyrimidine synthesis. As a result, tumor cells with impaired de novo pyrimidine synthesis showed depleted UMP and displayed enhanced exposure of phosphatidylserine (PtdSer), a major “eat-me” signal, thereby promoting macrophage-mediated phagocytosis. In multiple pancreatic cancer models, Cad-deficient tumors exhibited markedly reduced tumor burden with increased levels of phagocytosis by macrophages. Importantly, the Cad-mediated suppression of pancreatic cancer was dependent on TAMs and cytokines IL-1 and TNF-α. Pharmacological inhibition of DHODH, which blocks de novo pyrimidine synthesis, similarly decreased tumor burden with enhanced phagocytosis in pancreatic cancer models. These findings highlight the critical role of the tumor-intrinsic pyrimidine synthesis pathway in modulating macrophage-mediated antitumor immunity, with potential therapeutic implications.
Authors
Jie Zhao, Xinghao Li, Xinyu Li, Pengfei Ren, Yilan Wu, Hao Gong, Lijian Wu, Junran Huang, Saisai Wang, Ziwei Guo, Mo Chen, Zexian Zeng, Deng Pan
Abstract
Authors
William Ang, Travis D. Kerr, Ananya Kodiboyena, Cristina Valero, Joris L. Vos, Vladimir Makarov, Alex A. Adjei, Luc G.T. Morris, Stephanie L. Schmit, Natalie L. Silver, Sujata Patil, Daniel J. McGrail
Abstract
Authors
Dalin Zhang, Chun-Lung Chiu, Fernando Jose Garcia Marques, Abel Bermudez, Christian R. Hoerner, Nicholas Hadi, Elise Wang, Thomas J. Metzner, Ludimila Trabanino, John T. Leppert, Hongjuan Zhao, Robert Tibshirani, Alice C. Fan, Sharon J. Pitteri, James D. Brooks
Abstract
CAR-T therapy has led to significant improvements in patient survival. However, a subset of patients experience high-grade toxicities, including cytokine release syndrome (CRS) and immune cell-associated hematological toxicity (ICAHT). We utilized IL-2Rα knockout mice to model toxicities with elevated levels of IL6, IFNγ, and TNFα and increased M1-like macrophages. Onset of CRS was accompanied by a reduction in peripheral blood neutrophils due to disruption of bone marrow neutrophil homeostasis characterized by an increase in apoptotic neutrophils and a decrease in proliferative and mature neutrophils. Both non-tumor-bearing and Eμ-ALL tumor-bearing mice recapitulated the co-occurrence of CRS and neutropenia. IFNγ-blockade alleviated CRS and neutropenia without affecting CAR-T efficacy. Mechanistically, a Th1-Th17 imbalance was observed to drive co-occurrence of CRS and neutropenia in an IFNγ-dependent manner leading to decreased IL-17A and G-CSF, neutrophil production, and neutrophil survival. In patients, we observed an increase in the IFNγ-to-IL-17A ratio in the peripheral blood during high-grade CRS and neutropenia. We have uncovered a biological basis for ICAHT and provide support for the use of IFNγ-blockade to reduce both CRS and neutropenia.
Authors
Payal Goala, Yongliang Zhang, Nolan J. Beatty, Allan Pavy, Shannon L. McSain, Cooper J. Sailer, Muhammad Junaid Tariq, Showkat Hamid, Eduardo Cortes Gomez, Jianmin Wang, Duna Massillon, Maxwell Ilecki, Justin C. Boucher, Constanza Savid-Frontera, Sae Bom Lee, Hiroshi Kotani, Meredith L. Stone, Michael D. Jain, Marco L. Davila
Abstract
The E3 ligase SPOP plays a context-dependent role in cancer by targeting specific cellular proteins for degradation, thereby influencing cell behavior. However, its role in tumor immunity remains largely unexplored. In this study, we revealed that SPOP targeted the innate immune sensor STING for degradation in a CK1γ phosphorylation-dependent manner to promote melanoma growth. Stabilization of STING by escaping SPOP-mediated degradation enhanced anti-tumor immunity by increasing IFNβ production and ISG expression. Notably, small-molecule SPOP inhibitors not only blocked STING recognition by SPOP, but also acted as molecular glues, redirecting SPOP to target neo-substrates such as CBX4 for degradation. This CBX4 degradation led to increased DNA damage, which in turn activated STING and amplified innate immune responses. In a xenografted melanoma B16 tumor model, single-cell RNA-seq analysis demonstrated that SPOP inhibition induced the infiltration of immune cells associated with anti-PD1 responses. Consequently, SPOP inhibitors synergized with immune checkpoint blockade to suppress B16 tumor growth in syngeneic murine models and enhanced the efficacy of CD19-CAR-T therapy. Our findings highlight a molecular glue degrader property of SPOP inhibitors, with potential implications for other E3 ligase-targeting small molecules designed to disrupt protein-protein interactions.
Authors
Zhichuan Zhu, Xin Zhou, Max Xu, Jianfeng Chen, Kevin C. Robertson, Gatphan N. Atassi, Mark G. Woodcock, Allie C. Mills, Laura E. Herring, Gianpietro Dotti, Pengda Liu
Abstract
Liver metastases are relatively resistant to checkpoint blockade immunotherapy. The hepatic tissue has distinctive features including high numbers of NK cells. It was therefore important to conduct in depth single-cell analysis of NK cells in colorectal cancer liver metastases (CRLMs) with the effort to dissect their diversity and to identify candidate therapeutic targets. By combining unbiased single-cell transcriptomic with multiparametric flow cytometry analysis, we identified an abundant family of intrahepatic CD56Bright NK cells in CRLMs endowed with anti-tumor functions resulting from specific transcriptional liver programs. Intrahepatic CD56Bright and CD56Dim NK lymphocytes expressed unique transcription factors (IRF8, TOX2), high level of chemokines, and targetable immune checkpoints (ICs), including CXCR4 and the IL-1 receptor family member IL-1R8. CXCR4 pharmacological blocking and an anti-IL-1R8 mAb enhanced the effector function of CRLM NK cells. Targeting the diversity of liver NK cells and their distinct immune-checkpoint repertoires is key to optimize the current immune-therapy protocols in CRLM.
Authors
Joanna Mikulak, Domenico Supino, Paolo Marzano, Sara Terzoli, Roberta Carriero, Valentina Cazzetta, Rocco Piazza, Elena Bruni, Paolo Kunderfranco, Alessia Donato, Sarah Natalia Mapelli, Roberto Garuti, Silvia Carnevale, Francesco Scavello, Elena Magrini, Jelena Zeleznjak, Clelia Peano, Matteo Donadon, Guido Costa, Guido Torzilli, Alberto Mantovani, Cecilia Garlanda, Domenico Mavilio
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)