Immunogenic Cell Death Research Articles

Enhancing Radiofrequency Ablation for Hepatocellular Carcinoma: Nano-Epidrug Effects on Immune Modulation and Antigenicity Restoration.

Radiofrequency ablation (RFA), a critical therapy for hepatocellular carcinoma (HCC), carries a significant risk of recurrence and metastasis, particularly owing to mechanisms involving immune evasion and antigen downregulation via epigenetic modifications. This study introduces a "nano-epidrug" named MFMP. MFMP, which is composed of hollow mesoporous manganese dioxide (MnO2) nanoparticles, FIDAS-5 as an MAT2A inhibitor, macrophage membrane, and anti-PD-L1 (aPD-L1), targets HCC cells. By selectively binding to these cells, MFMP initially reverses immune suppression via PD-L1 inhibition. After endocytosis, MFMP disassembles in the tumor microenvironment, releasing FIDAS-5 and Mn2+. FIDAS-5 prevents cGAS methylation, whereas Mn2+ aids STING pathway restoration. In addition, FIDAS-5 reduces m6A RNA modification, suppressing EGFR expression. These changes enhance HCC antigenicity to promote cytotoxic T cell recognition and cytotoxic killing. Furthermore, MFMP mediates immunogenic cell death in HCC by synergizing with RFA through cGAS DNA demethylation, EGFR mRNA demethylation, and TBK1 protein phosphorylation, thereby inhibiting recurrence and metastasis and enhancing immune memory. Thus, MFMP is a potential adjunctive therapy requiring clinical validation.

Charge Separation-Engineered Piezoelectric Ultrathin Nanorods Modulate Tumor Stromal Microenvironment and Enhance Cell Immunogenicity for Synergistically Piezo-Thermal-Immune Therapy.

The tumor microenvironment (TME) is characterized by hypoxia and low immunogenicity, with a dense and rigid extracellular matrix (ECM) that impedes the diffusion of therapeutic agents and immune cells, thereby limiting the efficacy of immunotherapy. To overcome these challenges, an oxygen defect piezoelectric-photothermal sensitizer, bismuth vanadate nanorod-supported platinum nanodots (BVP) is developed. The integration of platinum enhances the photothermal effect and improves charge separation efficiency under ultrasound, leading to increased heat generation and the production of reactive oxygen species (ROS) and oxygen. Platinum also catalyzes the conversion of hydrogen peroxide in the TME to oxygen, which serves as both a ROS source and a means to alleviate tumor hypoxia, thereby reversing the immunosuppressive TME. Moreover, the coordination of bismuth ions with glutathione further amplifies cellular oxidative stress. The generated heat and ROS not only denature the collagen in the ECM, facilitating the deeper penetration of BVP into the tumor but also induce immunogenic cell death in tumor cells. Through the "degeneration and penetration" strategy, photoacoustic therapy effectively activates immune cells, inhibiting both tumor growth and metastasis. This study introduces a pioneering approach in the design of antitumor nanomedicines aimed at reversing the immunosuppressive characteristics of the TME.

Ro 90-7501 suppresses colon cancer progression by inducing immunogenic cell death and promoting RIG-1-mediated autophagy.

Colon cancer is one of the leading causes of cancer-related mortality worldwide. Current treatments, including surgery, chemotherapy, and radiation therapy, often have limited efficacy due to tumor heterogeneity and resistance mechanisms. Therefore, there is a critical need for novel therapeutic strategies that can enhance the immune response against colon cancer cells while promoting their efficient clearance. In this study, we investigated the anti-tumor effects of Ro 90-7501, a specific small molecule, in colon cancer cell lines (HCT8 and SW480) and in vivo models. MTS, EdU, Scratch Wound and Transwell assays were performed to detect the cell proliferation and metastasis. Additionally, flow cytometry and immunofluorescence staining were used to analyze changes in apoptosis and necrosis. Furthermore, we examined its ability to induce immunogenic cell death (ICD) and promote retinoic acid-inducible gene I (RIG-I)-mediated autophagy. The expression levels of key molecules involved in ICD and autophagy were assessed using Western blot analysis, immunofluorescence staining, and enzyme-linked immunosorbent assay (ELISA). Our findings demonstrated that Ro 90-7501 significantly suppressed colon cancer cell proliferation and metastasis, inducing apoptosis and necrosis. Mechanistically, Ro 90-7501 triggered ICD by upregulating the exposure of calreticulin (CRT) on the cell surface and increasing the release of high mobility group box 1 (HMGB1) and extracellular ATP levels. Concurrently, it promoted RIG-I-mediated autophagy via the MAVS-TRAF6 signaling axis, evidenced by increased expression of autophagy-related genes, such as microtubule-associated protein 1 light chain 3 (LC3) and Beclin 1 proteins, coupled with a reduction in P62 protein. Additionally, Ro 90-7501 treatment activated the RIG-I-MAVS-TRAF6 signaling axis in colon cancer cells. Furthermore, Ro 90-7501 enhanced the secretion of pro-inflammatory cytokines, such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNFα), thereby activating the immune response. In conclusion, Ro 90-7501 exhibits potent anti-tumor activity against colon cancer by inducing ICD and promoting RIG-I-mediated autophagy. These results suggest that Ro 90-7501 may serve as a promising therapeutic candidate for colon cancer treatment by enhancing both intrinsic cellular processes and adaptive immune responses. Further studies are warranted to elucidate the detailed mechanisms underlying these effects and to evaluate its therapeutic potential in clinical settings.

Oligopeptide template-guided nanoconfined in situ mineralization of nanotherapeutics boosts self-sufficient immunogenic phototherapy.

As a promising cancer treatment modality that has emerged, photodynamic / photothermal therapy can harness antitumor immunity by triggering immunogenic cell death in addition to direct cell ablation. However, the efficacy of this phototherapy is always limited due to the hypoxic tumor microenvironment, and the induccd immune stimulation is insufficient to achieve satisfactory cancer eradication. We herein address the above issues by nanoconfined in situ mineralization of manganese oxide (MnO2) guided with an oligopeptide as template. The synthetic nanocomposites can be co-assembled efficiently with the photosensitiser through π-π stacking interactions. Crucially, the mineralised MnO2 composition catalytically decomposes tumor-derived hydrogen peroxide to alleviate the hypoxic microenvironment, thereby improving the efficacy of the photosensitiser in ROS generation. In the murine model of 4 T1 xenograft tumors, the fabricated nanotherapeutics elicited robust antitumor immune responses and boost immunogenic phototherapy toward malignant tumors.

Nanoplatform-based synergistic cancer Immuno-Chemodynamic therapy.

Immunotherapy has made excellent breakthroughs in the field of cancer treatments, but faces challenges with low immunogenicity of tumor cells and an immunosuppressive tumor microenvironment (ITME). The emerging chemodynamic therapy (CDT) based on the Fenton/Fenton-like reaction can induce immunogenic cell death (ICD) to enhance tumor immunogenicity, facilitating the transition from immune-cold to immune-hot tumors. Synergistic CDT and immunotherapy based on advanced nanotechnology have shown immense promise for improving therapeutic efficacy while minimizing side effects in cancer treatment. This review summarizes and discusses recent advances in the field, with the goal of designing a high-quality nanoplatform to enhance synergistic CDT in combination with immunotherapy and lay the foundation for its future clinical translation.

The circRNA cEMSY Induces Immunogenic Cell Death and Boosts Immunotherapy Efficacy in Lung Adenocarcinoma.

Immunogenic cell death (ICD) induces an active immune response. Activating ICD represents a potential approach to boost the anti-tumor activity of immunotherapy, highlighting the need to identify effective and safe ICD inducers. In this study, we identified a conserved, ICD-related circular RNA cEMSY by systematically screening ICD models induced by multiple cell stressors in lung adenocarcinoma (LUAD). cEMSY triggered ICD in LUAD both in vitro and in vivo, leading to the release of damage-associated molecular patterns and promoting T cell cross-priming by dendritic cells (DCs). Notably, the intratumoral delivery of lipid nanoparticle-encapsulated cEMSY induced a potent antitumor immune response in an immunosuppressed tumor model, which synergized with PD-1 blockade to facilitate long-term anti-tumor immunity with no apparent toxicities. Mechanistically, cEMSY mediated mitochondrial aggregation of the RNA-binding protein TDP-43 that enabled leakage of mitochondrial DNA to stimulate the cGAS-STING pathway, activating the antiviral immune response. Clinically, elevated expression of cEMSY correlated with enhanced infiltration of DCs and CD8+ T cells and favorable immunotherapy response in LUAD. Together, these findings support the dual potential of cEMSY as a target and biomarker for improving immune checkpoint inhibitor responses in LUAD.

Ferroptosis to Pyroptosis Regulation by Iron-Based Nanocatalysts for Enhanced Tumor Immunotherapy.

Immunogenic cell death serves as a pivotal mechanism in enhancing antitumor immunotherapy by engaging both innate and adaptive immune responses. However, a key unanswered question is which mode of cell death, particularly ferroptosis or pyroptosis, serves as the optimal pathway for activating the immune response. In this study, we introduce an innovative iron-based nanocatalytic medicine that strategically regulates ferroptosis to pyroptosis to augment antitumor immunotherapy. By harnessing the intricate interplay between iron and carbonyl cyanide m-chlorophenyl hydrazone (CP), we engineered the nanomedicine which is capable of regulating ferroptosis to the more immunogenic pyroptosis within tumor cells. In vitro analyses revealed that the treatment with CP-encapsulated iron-based nanomedicine (HFCP) can effectively induce pyroptosis of cancer cells, exhibiting greatly enhanced efficacy in eradicating tumor cells and stimulating immune responses compared to the ferroptosis-inducing counterpart without CP incorporation (iron alone). Resultantly, HFCP not only effectively inhibited primary tumor growth but also suppressed the growth of untreated distant tumors to a large extent, underscoring a notably induced immune memory. Taken together, these results indicate that HFCP-induced pyroptosis offers a significantly more powerful approach to tumor immunotherapy than ferroptosis, offering promising potentials for achieving long-term immunotherapeutic outcomes through the reversal of the immunosuppressive tumor microenvironment and the effective regulation of immunogenic cell death modes.

Engineered Biomimetic Cancer Cell Membrane Nanosystems Trigger Gas-Immunometabolic Therapy for Spinal-Metastasized Tumors.

Despite great progress in enhancing tumor immunogenicity, conventional gas therapy cannot effectively reverse the tumor immunosuppressive microenvironment (TIME), limiting immunotherapy. The development of therapeutic gases that are tumor microenvironment responsive and efficiently reverse the TIME for precisely targeted tumor gas-immunometabolic therapy remains a great challenge. In this study, a novel cancer cell membrane-encapsulated pH-responsive nitric oxide (NO)-releasing biomimetic nanosystem (MP@AL) is prepared. Lactate oxidase (Lox) in MP@AL consumed oxygen to promote the decomposition of lactate, a metabolic by-product of tumor glycolysis, and the generation of H2O2, while L-arginine (L-Arg) in MP@AL is oxidized by H2O2 to generate nitric oxide (NO). For one thing, NO led to mitochondrial dysfunction in tumor cells to reduce oxygen consumption and promote the efficiency of Lox in lactate decomposition, thus reversing lactate-induced TIME; for another, NO effectively triggered immunogenic cell death, activated anti-tumor immune response and long-term immune memory, and ensured a favorable effect in the synergistic interaction with PD-L1 antibody for inhibiting tumor growth and recurrence. Therefore, a novel gas-immunometabolic therapy dual closed-loop nanosystem for enhancing tumor immunogenicity and remodeling lactate-induced TIME is established. Overall, this work will provide new ideas for gas therapy to effectively remodel the TIME to enhance cancer immunotherapy.

EXTH-66. ONCOLYTIC ADENOVIRAL INFECTION SYNERGIZES WITH IMMUNE CHECKPOINT INHIBITION TO MEDIATE INTRACRANIAL TUMOR CONTROL IN DISPARATE MODELS OF MELANOMA BRAIN METASTASES

Abstract Amongst all solid cancers, melanoma brain metastases (MBM) have the highest likelihood of metastasizing to the brain. The emergence of immune checkpoint inhibitors (ICI) for metastatic melanoma have demonstrated increasingly promising results; however, intracranial progression remains a challenging obstacle. Oncolytic viral (OV) therapy leverages tumor cell replication machinery to selectively replicate and kill tumor cells and promote anti-tumor immunity. We propose this OV strategy can be applied to MBM through direct tumor infection that simultaneously sustains a distant antitumor immune response. To counteract immunosuppressive features of the tumor microenvironment (TME), a third-generation oncolytic adenovirus (Delta-24-RGDOX) has been developed which expresses the immune stimulatory OX40 ligand (OX40L). We quantified the cytotoxic capacity of Delta-24-RGDOX and its ability to achieve immunogenic cell death (ICD) in vitro along with cerebral organoid co-culture models. Additionally, we used a series of syngeneic murine melanoma models to explore local and systemic antitumor immunity following Delta-24-RGDOX infection. Delta-24-RGDOX inoculation achieved viral infection, OX40L cell surface expression, tumor cell cytotoxicity, and ICD in vitro. Viral oncolysis was recapitulated in a cerebral organoid melanoma co-culture model with concomitant alterations in microglia activation and detection of viral transcripts within microglia using single cell RNA sequencing, suggesting a viral-clearing role of microglia within the TME. Local tumor clearance was achieved in orthotopic intracranial models following direct intracranial viral inoculation alone, and in combination with ICI. Lastly, we demonstrated improvement in overall survival in a synchronous subcutaneous/intracranial B16F10 model where the subcutaneous tumor was treated with Delta-24-RGDOX in combination with ICI. In summary, Delta-24-RGDOX achieves viral infection, oncolysis, and ICD following infection of melanoma cell lines. These findings translated in multiple in vivo models including immune cell activation and systemic antitumor immunity against uninfected MBM. Future studies are needed to explore the role of immune cell trafficking, myeloid cell modulation, T cell priming, and clonal expansion withing locally infected and the distant melanoma TME.

EXTH-67. ONCOLYTIC ADENOVIRAL INFECTION OF CHORDOMA ACHIEVES TREATMENT EFFICACY THROUGH IMMUNOGENIC CELL DEATH AND TUMOR MICROENVIRONMENT ALTERATION

Abstract Chordomas are locally aggressive neoplasms of the axial skeleton with recurrence rates approaching 40%. Moreover, recurrent chordomas are nearly impossible to eradicate—highlighting an unmet clinical need. Immunotherapeutic approaches, such as immune checkpoint inhibition (ICI), has been a successful tool to modulate the tumor microenvironment (TME) towards a pro-inflammatory, antitumor state. There is emerging interest in exploring immunomodulatory agents for chordomas. Oncolytic viral (OV) therapy uses genetically modified viruses which selectively replicate in tumor cells, mediate tumor cell lysis, and initiate a pro-inflammatory response within the infected TME. These findings suggest that OV therapy may be a clinically relevant, novel immunotherapeutic approach for chordoma. Using the replicating oncolytic adenovirus Delta-24-RGD, we investigate the efficacy of chordoma treatment using in vitro approaches, ex vivo bone scaffolds, and in vivo murine models. Additionally, we explore the underlying mechanism of OV cytotoxicity, immunogenic cell death, Brachyury modulation, and reshaping of the TME towards a pro-inflammatory state. Across a panel of human chordoma cell lines, Delta-24-RGD achieved viral infectivity, oncolysis and immunogenic cell death. This treatment response was similarly demonstrated in chordoma cultured in bone scaffold models. Delta-24-RGD infection was associated with concomitant Brachyury downregulation within both infected and uninfected chordoma cells in vitro, suggesting a pleiotropic effect following oncolytic viral infection. In vivo models of CH22 chordoma treated with Delta-24-RGD demonstrated shrinkage in tumor volume and enhanced overall survival. Utilizing a human chordoma tissue microarray, the immunosuppressive macrophage marker CD163 was associated with shortened recurrence free survival. Using macrophage/chordoma co-culture, Delta-24-RGD infection achieved a reduction in macrophage expression of CD163. Taken together, Delta-24-RGD demonstrated efficacy in multiple models of chordoma including mice bearing CH22 tumors. The chordoma TME is associated with clinical outcomes and Delta-24-RGD infection reverses a deleterious immunosuppressive immune profile. These studies provide a framework for future clinical trial implementation for patients with metastatic or recurrent chordoma.

Integrated multiomics analysis identified comprehensive crosstalk between diverse programmed cell death patterns and novel molecular subtypes in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is a highly aggressive malignancy with increasing global prevalence and is one of the leading causes of cancer-related mortality in the human population. Developing robust clinical prediction models and prognostic stratification strategies is crucial for developing individualized treatment plans. A range of novel forms of programmed cell death (PCD) plays a role in the pathological progression and advancement of HCC, and in-depth study of PCD is expected to further improve the prognosis of HCC patients. Sixteen patterns (apoptosis, autophagy, anoikis, lysosome-dependent cell death, immunogenic cell death, necroptosis, ferroptosis, netosis, pyroptosis, disulfidptosis, entotic cell death, cuproptosis, parthanatos, netotic cell death, alkaliptosis, and oxeiptosis) related to PCD were collected from the literatures and used for subsequent analysis. Supervised (Elastic net, Random Forest, XgBoost, and Boruta) and unsupervised (Nonnegative Matrix Factorization, NMF) clustering algorithms were applied to develop and validate a novel classifier for the individualized management of HCC patients at the transcriptomic, proteomic and single-cell levels. Multiple machine learning algorithms developed a programmed cell death index (PCDI) comprising five robust signatures (FTL, G6PD, SLC2A1, HTRA2, and DLAT) in four independent HCC cohorts, and a higher PCDI was predictive of higher pathological grades and worse prognoses. Furthermore, a higher PCDI was found to be correlated with the presence of a repressive tumor immune microenvironment (TME), as determined through an integrated examination of bulk and single-cell transcriptome data. In addition, patients with TP53 mutation had higher PCDI in comparison with TP53 WT patients. Three HCC subtypes were identified through unsupervised clustering (NMF), exhibiting distinct prognoses and significant biological processes, among the three subtypes, PCDcluster 3 was of particular interest as it contained a large proportion of patients with high risk and low metabolic activity. Construction and evaluation of the Nomogram model was drawn based on the multivariate logistic regression analysis, and highlighted the robustness of the Nomogram model in other independent HCC cohorts. Finally, to explore the prognostic value, we also validated the frequent upregulation of DLAT in a real-world cohort of human HCC specimens by qPCR, western blot, and immunohistochemical staining (IHC). Together, our work herein comprehensively emphasized PCD-related patterns and key regulators, such as DLAT, contributed to the evolution and prognosis of tumor foci in HCC patients, and strengthened our understanding of PCD characteristics and promoted more effective risk stratification strategies.

CTIM-36. IN-SITU VACCINATION OF BIOPSY-ONLY GBM TUMORS BY TUMOR TREATING FIELDS PLUS ANTI-PD-1 IMMUNOTHERAPY RESULTS IN ROBUST ANTIGEN-SPECIFIC T CELL SELECTION AND EXPANSION, HIGH RESPONSE RATE, AND SIGNIFICANTLY EXTENDED SURVIVAL

Abstract We have recently described a complete in-situ immunizing protocol against GBM using Tumor Treating Fields (TTFields) to activate the DNA sensor-dependent inflammasomes and immunogenic cell death. Here, we report successful in-situ vaccination of patients with newly diagnosed GBM, especially in those with bulky, biopsy-only tumors as compared to those with maximally resected disease, using TTFields together with pembrolizumab, an anti-PD-1 immunotherapy. Patients with biopsy-only tumors displayed a marked improvement in both progression-free survival (27.2m vs 9.6m; HR 0.37, 95%CI 0.16-0.85; P=0.014), overall survival (31.6m vs 18.8m; HR 0.4, 95%CI 0.17-0.92; P=0.023), and response rates (66.6% vs 25%) when compared to those with maximally resected tumors. Using a combination of bulk RNA-seq of enriched T cells and single-cell RNA-seq and TCR clonotyping of tumors and PBMC, we tracked clonal evolution of T cells and confirmed that TTFields’ adaptive immune activation followed a type 1 interferon trajectory (T1IFN) specifically through the DC compartment in patients with biopsy-only tumor. From DC, the T1IFN pathway engaged the adaptive immune system, highly correlated with T cell activation (Pearson r=0.81; P=0.000027), and strongly predicted for extended survival (HR 0.3; P=0.034). Importantly, we discovered the adaptive replacement of expanded T cell clones induced by TTFields and enhanced by pembrolizumab predicted for prolonged survival (P=0.031), leading to sustained T cell activation (Pearson r=0.72; P=0.0018) and robust generation of central memory CD4+ and CD8+ T cells, especially in responders with biopsy-only tumors. In recurrent tumors, the PD-1/PD-L1 axis was suppressed, while concurrent upregulation of alternative immune checkpoints was observed in the periphery and TME. This was coupled with ineffective compensatory T cell activation, suggesting potential mechanisms of resistance. These findings highlight the potent in-situ vaccination effects of TTFields and support its co-application with immune checkpoint inhibitors as a promising strategy for GBM, especially in patients with substantial residual tumor.

CTIM-17. INDIVIDUALIZED MULTIMODAL IMMUNOTHERAPY (IMI) FOR ADULTS WITH DIFFUSE MIDLINE GLIOMA OR DIFFUSE HEMISPHERIC GLIOMA

Abstract Diffuse Midline Glioma (DMG, H3K27 mutant) and Diffuse Hemispheric Glioma (DHG, H3G34 mutant) are rare malignant CNS tumors with dismal prognosis. We retrospectively searched in our database for adults (>18y) with molecularly define DMG/DHG, treated between May 2015 and 2024 with IMI as part of first-line treatment. Amongst 157 IMI-treated malignant glioma patients, four patients fit these restrictions, pointing to scarce experience of IMI for DMG/DHG adult patients. HM (M, 29y) was diagnosed with a DMG in the pons. He received radiochemotherapy, and continued after 2x TMZm with BRAF-MEK-inhibition therapy. He received one IO-Vac® dendritic cell vaccine but showed fast progression thereafter. He died 9 months after diagnosis. GJE (F, 28y) had a DMG at the corpus callosum. She received radiochemotherapy and 6x TMZm, followed by 2x IO-Vac® and 3x maintenance immunogenic cell death (ICD) immunotherapy (NDV injections, sessions of modulated electrohyperthermia), combined with WT1 and H3K27M long-peptide vaccines. She progressed after 20 months, for which a new IO-Vac® and an H3K27M short- and long-peptide vaccine were given. She died 5 months later. Overall Survival (OS) was 26 months after initial diagnosis. JD (F, 27y) was diagnosed with a DMG in C2-C6. She received radiochemotherapy followed by IMI alone, including 2x IO-Vac®, one ICD immunotherapy, and four doses of anti-PD1. She died 17 months later, making OS 27 months after diagnosis. VJ (F, 21y) had a DHG in the left cerebrum. She received radiochemotherapy and 12 cycles of maintenance TMZ (TMZm), between which ICD immunotherapy was inserted each time. Afterwards, she received two IO-Vac®. Finally, she received ICD immunotherapy (6x) combined with checkpoint inhibitors (4x anti-CTLA4, 10x anti-PD1). Thirty months after diagnosis, she is in remission with a stable Health Utility Index of 0.72. IMI might have contributed to a better OS in three out of four DMG/DHG patients, and should be explored further as part of the treatment for these patients.

Proximal Anchoring of Nanodrugs through In Situ Generated Radical Hooks with Boosted Autophagy and Immunotherapy.

Efficient retention of drugs at tumor sites was always desirable to maximize therapeutic functions, yet the main concern is the dynamic blood clearance induced fast removal from localized lesion. Herein, a tumor microenvironment activated covalently conjugation (self- and proximal conjugation) of tyramine modified Pt nanoclusters (PCMT NPs) was constructed by in situ produced radical hooks, leading to efficient accumulation of PCMT NPs at tumor sites. Such accumulation further aggravated the oxidative stress and provoked autophagy of tumor cells via activating the caspase-3 pathway mediated massive apoptosis, thereby stimulating immunogenic cell death (ICD). As verified by in vivo results, the PCMT NPs effectively suppressed primary and distant tumor growth (with an inhibition rate of 99%) while eliciting immunotherapeutic responses. As such, a new paradigm for boosting drug retention was provided, which enabled specific tumor treatment with synergistic therapeutic outcomes.

CTIM-11. LONG-TERM SURVIVORS FROM A PHASE 1B STUDY OF IGV-001 IN PATIENTS WITH NEWLY DIAGNOSED GLIOBLASTOMA

Abstract Imvax has developed the Goldspire™ platform to create IGV-001, an autologous biologic-device combination product for the treatment of newly diagnosed glioblastoma (ndGBM). IGV-001 consists of autologous GBM tumor cells and an antisense oligonucleotide against IGF-1R mRNA (IMV-001), irradiated and administered via biodiffusion chambers (BDCs) implanted in the abdomen. Together, these components stimulate immunogenic cell death and antigen release. IGV-001 was well tolerated and multiple efficacy signals were observed in a Phase 1b study in patients with ndGBM (Andrews et al., 2021), including significant improvements in progression-free survival (PFS), radiographic evidence of tumor response, and changes in immune response biomarkers. The Phase 1b study enrolled 33 patients in four different cohorts implanted with 10 or 20 BDCs for 24 or 48 hours. Here we report on 6 subjects with survival beyond 4 years, including 5 subjects who survived 5 years or more (15.2%). There were 4 male and 2 female subjects, with a median age of 52 years (range 32-75). At diagnosis the MGMT promoter was methylated in 4 of 5 subjects that survived 5 years or more. We also report on T cell receptor Vβ CDR3 region sequencing of peripheral blood mononuclear cells and tissue infiltrated lymphocytes that was performed in a subset of 9 patients, including 3 subjects who survived beyond 4 years. Immune correlates of IGV-001 suggest an association between peripheral T cell clonal expansion and PFS/OS outcomes. A Phase 2b randomized, multicenter, double-blind, placebo-controlled study to assess the safety and efficacy of IGV-001 in patients with ndGBM (NCT04485949) has completed enrollment and results are expected to be available in 2025.

IMMU-62. INVIGORATING EFFECTOR IMMUNE CELLS WITH HIGHLY SELECTIVE IL-2R AGONISTS AND POTENTIAL SYNERGY WITH TUMOR TARGETING THERAPEUTICS FOR TREATMENT OF GLIOBLASTOMAS

Abstract Glioblastoma (GBM) is an aggressive brain tumor with a median overall survival (mOS) of 14 months. Treatment options are limited with no new approved therapies over the past 3 decades and no standard of care for a majority of patients (> 90%) who experience recurrence. GBM has a highly immune suppressive tumor microenvironment (TME) comprising of myeloid derived suppressor cells (MDSCs) and tumor associated macrophages (TAMs) that are capable of suppressing the activity of anti-cancer CD8+ T and NK cells. We have engineered highly selective IL-2 superkines (IL-2SK) that preferentially expand and activate CD8+ T and NK cells with limited effects on immune suppressive regulatory T cells (i.e., Tregs). MDNA11 is an IL-2SK -albumin fusion protein designed to increase half-life and promote tumor accumulation. MDNA223 is a bi-functional anti-PD1-IL-2SK designed to stimulate effector immune cells while preventing immune exhaustion. MDNA11 and MDNA223 extended survival of mice harboring orthotopic GBM tumors with accompanying increase in CD8+ T and NK cells within the TME. When patient-derived GBM tumor explants were treated with MDNA11 and MDNA223 ex vivo, there was clear evidence of activation among resident CD8+ T cells characterized by increased levels of intra-cellular Granzyme B responsible for tumor cell killing. There was also increased release of soluble Fas ligand and granulysin, consistent with an activated anti-tumor immune response within the TME. Ongoing studies include in depth immune profiling to further understand the mechanism of MDNA11 and MDNA223 in GBM as well as to test potential synergy with tumor targeting therapeutics and other treatment modalities capable of eliciting immunogenic cell death.

CTNI-18. RESULTS FROM A PHASE 1 STUDY OF SONODYNAMIC THERAPY WITH WHOLE HEMISPHERIC LOW INTENSITY NON-ABLATIVE ULTRASOUND IN PATIENTS WITH RECURRENT HIGH GRADE GLIOMA

Abstract We report the first use of a novel device that delivers non-ablative low intensity diffuse ultrasound (LIDU) across the entire hemisphere in combination with the oral sonosensitizing agent 5-ALA for the treatment of recurrent high grade glioma. LIDU in combination with 5-ALA focally targets tumor cells with sonodynamic therapy (SDT), causing selective tumor cell death across the entire hemisphere via 1) direct tumor targeting and 2) stimulation of immunogenic cell death. In this 3x3 clinical trial designed for safety (n=12, NCT05362409), two patients were enrolled after multiple recurrences and seven patients had multifocal or multicentric disease. Treatments were delivered monthly for a minimum of four sessions. A treatment duration of 120 minutes was established after dose escalation and expansion. SDT delivered via a novel device and in conjunction with 5-ALA was well tolerated, with no duration-limiting toxicities or serious related adverse events. Compared to historical data, we observed a significant increase in overall survival (mOS of 14.0+ months, with 7 of 12 patients still alive at the time of this submission and final median OS not yet achieved). A Phase 2b randomized, multicenter, double-blind, placebo-controlled study has been planned to commence in 2025 to assess the safety and efficacy of LIDU with sonosensitization in patients with newly diagnosed GBM.

Silver nanoparticle induced immunogenic cell death can improve immunotherapy

Cancer immunotherapy is often hindered by an immunosuppressive tumor microenvironment (TME). Various strategies are being evaluated to shift the TME from an immunologically ‘cold’ to ‘hot’ tumor and hereby improve current immune checkpoint blockades (ICB). One particular hot topic is the use of combination therapies. Here, we set out to screen a variety of metallic nanoparticles and explored their in vitro toxicity against a series of tumor and non-tumor cell lines. For silver nanoparticles, we also explored the effects of core size and surface chemistry on cytotoxicity. Ag-citrate-5 nm nanoparticles were found to induce high cytotoxicity in Renca cells through excessive generation of reactive oxygen species (ROS) and significantly increased cytokine production. The induced toxicity resulted in a shift of the immunogenic cell death (ICD) marker calreticulin to the cell surface in vitro and in vivo. Subcutaneous Renca tumors were treated with anti-PD1 or in combination with Ag-citrate-5 nm. The combination group resulted in significant reduction in tumor size, increased necrosis, and immune cell infiltration at the tumor site. Inhibition of cytotoxic CD8 + T cells confirmed the involvement of these cells in the observed therapeutic effects. Our results suggest that Ag-citrate-5 nm is able to promote immune cell influx and increase tumor responsiveness to ICB therapies.

Discovery of the First-in-Class Dual-Target ROCK/HDAC Inhibitor with Potent Antitumor Efficacy in Vivo That Trigger Antitumor Immunity.

Triple-negative breast cancer (TNBC) represents a highly aggressive and heterogeneous malignancy. Currently, multitarget drug approaches present a promising therapeutic approach for TNBC. Utilizing a combinatorial chemistry strategy to construct a virtual screening database, dual ROCK/HDAC-targeting benzothiophene compounds were identified. Notably, compound 10h effectively inhibits ROCK1/2 and HDAC1/2/3/6/8 while demonstrating potent antiproliferative activity against breast cancer cells. In an orthotopic mouse model of breast cancer, 10h significantly suppressed tumor growth without apparent toxicity. Importantly, 10h induced immunogenic cell death (ICD), promoted dendritic cells (DCs) maturation, and activated T cells, thereby initiating antitumor immunity. In conclusion, compound 10h is a novel dual-target ROCK/HDAC inhibitor that represents a promising treatment strategy for TNBC.

Biomimetic Dual‐Driven Heterojunction Nanomotors for Targeted Catalytic Immunotherapy of Glioblastoma

AbstractThe existence of the blood–brain barrier (BBB) and the characteristics of the immunosuppressive microenvironment in glioblastoma (GBM) present significant challenges for targeted GBM therapy. To address this, a biomimetic hybrid cell membrane‐modified dual‐driven heterojunction nanomotor (HM@MnO2‐AuNR‐SiO2) is proposed for targeted GBM treatment. These nanomotors are designed to bypass the BBB and target glioma regions by mimicking the surface characteristics of GBM and macrophage membranes. More importantly, the MnO2‐AuNR‐SiO2 heterojunction structure enables dual‐driven propulsion through near‐infrared‐II (NIR‐II) light and oxygen bubbles, allowing effective treatment at deep tumor sites. Meanwhile, the plasmonic AuNR‐MnO2 heterostructure facilitates the separation of electron–hole pairs and generates reactive oxygen species (ROS), inducing immunogenic tumor cell death under NIR‐II laser irradiation. Furthermore, MnO2 in the tumor microenvironment reacts to release Mn2+ ions, activating the cGAS‐STING pathway and enhancing antitumor immunity. In vitro and in vivo experiments demonstrate that these dual‐driven biomimetic nanomotors achieve active targeting and deep tumor infiltration, promoting M1 macrophage polarization, dendritic cell maturation, and effector T‐cell activation, thereby enhancing GBM catalysis and immunotherapy through ROS production and STING pathway activation.