Integrating mild hyperthermia (MH) with 125I brachytherapy holds potential for overcoming treatment resistance and improving anticancer efficacy. Here, magnetic nanoparticles (MNPs) with a suitable Curie temperature are constructed and incorporated with silver rods coated with 125I to form composite seeds. In vitro simulations and in vivo validations demonstrated their effective performance in radiation dose and temperature control. Compared with traditional thermoseeds and previously reported MNPs, this composite seed exhibits direction-independent and self-regulated heating efficiency. Additionally, the titanium shell prevented MNPs leakage and enabled its repeated hyperthermia treatment capacity. Subsequently, the enhanced pancancer anticancer efficacy of the composite seed-relied 125I@MH therapy is confirmed through cellular and animal experiments involving liver cancer and prostate cancer. Further tumor microenvironment investigations based on a subcutaneous liver cancer mouse model identified that 125I therapy recruited Cd274/Pd-l1+ neutrophils and induced T-cell exhaustion, leading to immune evasion and brachytherapy resistance. The addition of MH significantly reversed this effect, restoring the function of effector T cells (IFN-γ+ T cells) and activating T-cell immunity. In conclusion, this study developed a novel composite seed with superior anticancer efficacy, which holds promising therapeutic potential for the treatment of malignancies, particularly solid tumors, in future clinical practice.
© 2025 The Author(s). Advanced Science published by Wiley‐VCH GmbH.

Dendritic cells (DCs) are specialized immune cells that play a crucial role in presenting antigens and activating cytotoxic T lymphocytes to combat tumors. The immune checkpoint receptor programmed cell death-1 (PD-1) can bind to its ligand programmed cell death-ligand 1 (PD-L1), which is expressed on the surface of cancer cells. This interaction suppresses T-cell activation and promotes immune tolerance. Radiation therapy can increase the expression of PD-L1 on tumor cells, which can lead to a decrease in the effectiveness of the treatment, and detailed studies are needed to understand the mechanisms. As many patients develop resistance to chemotherapy and radiotherapy-either through lack of response or cancer recurrence-there is a critical need to maximize synergistic effects by selecting combination treatments that offer improved therapeutic efficacy with minimal side effects. In the present study, immature DCs (iDCs) were introduced directly into irradiated tumor sites (referred as IR/iDCs), and immune checkpoint blockades (ICBs) were administered intraperitoneally. We confirmed the antitumor effect of combining IR/iDCs and ICBs by examining tumor growth and mouse survival. The proportion of CD4 + and CD8 + T cells in splenocytes increased in the IR/iDCs-treated groups. Combining IR/iDCs with an anti-PD-L1 antibody led to a significant reduction in distant tumor growth and improved mouse survival rates compared with IR/iDCs alone or IR/iDCs + anti-PD-1 antibody. These findings suggest that integrating radiotherapy, DC-based immunotherapy, and ICB, specifically targeting PD-L1, may be an effective cancer treatment strategy.
Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.

The goal of therapeutic cancer vaccines and immune checkpoint therapy (ICT) is to promote T cells with anti-tumor capabilities. Here, we compared mutant neoantigen (neoAg) peptide-based vaccines with ICT in preclinical models. NeoAg vaccines induce the most robust expansion of proliferating and stem-like PD-1+TCF-1+ neoAg-specific CD8 T cells in tumors. Anti-CTLA-4 and/or anti-PD-1 ICT promotes intratumoral TCF-1- neoAg-specific CD8 T cells, although their phenotype depends in part on the specific ICT used. Anti-CTLA-4 also prompts substantial changes to CD4 T cells, including induction of ICOS+Bhlhe40+ T helper 1 (Th1)-like cells. Although neoAg vaccines or ICTs expand iNOS+ macrophages, neoAg vaccines maintain CX3CR1+CD206+ macrophages expressing the TREM2 receptor, unlike ICT, which suppresses them. TREM2 blockade enhances neoAg vaccine efficacy and is associated with fewer CX3CR1+CD206+ macrophages and induction of neoAg-specific CD8 T cells. Our findings highlight different mechanisms underlying neoAg vaccines and different forms of ICT and identify combinatorial therapies to enhance neoAg vaccine efficacy.
Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.

Aberrant activation of IL-18 signaling regulates tumor immune evasion and progression. However, the underlying mechanism remains unclear. Here, we report that long-chain acyl-CoA synthase 6 (ACSL6) is highly expressed in liver cancer and correlated with poor prognosis. ACSL6 promotes tumor growth, metastasis, and immune evasion mediated by IL-18, independent of its metabolic enzyme activity. Mechanistically, upon IL-18 stimulation, ACSL6 is phosphorylated by ERK2 at S674 and recruits IL-18RAP to interact with IL-18R1, thereby reinforcing the IL-18R1-IL-18RAP heterodimer and triggering NF-κB-dependent gene expression to facilitate tumor development. Furthermore, the up-regulation of CXCL1 and CXCL5 by ACSL6 promotes tumor-associated neutrophil and tumor-associated macrophage recruitment, thereby inhibiting cytotoxic CD8+ T cell infiltration. Ablation or S674A mutation of ACSL6 potentiated anti-PD-1 therapeutic efficacy by increasing the effector activity of intertumoral CD8+ T cells. We revealed that ACSL6 is a potential adaptor that activates IL-18-NF-κB axis-mediated tumor immune evasion and provides valuable insights for developing effective immunotherapy strategies for cancer.

Oncolytic Reovirus type 3 Dearing (RT3D), is a naturally occurring double-stranded (ds) RNA virus that is under development as an oncolytic immunotherapy We used an unbiased high-throughput cytotoxicity screen of different targeted therapeutic agents with the aim of identifying potential drug-viral sensitizers to enhance RT3D tumour killing. Talazoparib, a clinical poly(ADP)-ribose polymerase 1 (PARP-1) inhibitor, was identified as a top hit and found to cause profound sensitisation to RT3D. This effect was not seen with other classes of oncolytic virus and was not mediated by enhanced viral replication or PARP inhibitor-related effects on the DNA damage response. RT3D interacts with retinoic acid-induced gene-1 (RIG-I) and activates PARP-1, with consequent PARylation of components of the extrinsic apoptosis pathway. Pharmacological and genetic inhibition of PARP-1 abrogates this PARylation and increases levels of extrinsic apoptosis, NF-kB signalling and pro-inflammatory cell death. Direct interaction between PARP-1 and RIG-I following RT3D/talazoparib treatment is a key factor in activating downstream signaling pathways that lead to IFN-β and TNF-α/TRAIL production which, in turn, amplify the therapeutic effect through positive feedback. Critically, it was possible to phenocopy the effect of RT3D through the use of non-viral ds-RNA therapy and RIG-I agonism. In in vivo studies, we demonstrated profound combinatorial efficacy of RT3D and talazoparib in human A375 melanoma in immunodeficient mice. More impressively, in immunocompetent mouse models of 4434 murine melanoma, we achieved 100% tumour control and protection from subsequent tumour rechallenge with the combination regimen. Correlative immunophenotyping confirmed significant innate and adaptive immune activation with the combination of RT3D and PARP inhibition. Taken together, these data provide a clear line of sight to clinical translation of combined regimens of PARP inhibition or ds-RNA agonism, with either viral or non-viral agents, in tumour types beyond the relatively narrow confines of current licensed indications for PARP inhibition.