Journal for Immunotherapy of Cancer最新文献

Background: Oncolytic viruses are tumor-specific immunotherapeutic agents that exploit inherent features of the tumor microenvironment to replicate, spread, and kill cancer cells. The exchange protein activated by cAMP (EPAC) is a cell signaling protein that regulates pathways important for cell growth, survival, and migration, which are commonly associated with cancer progression, but are also very important for regulation of viral infectivity. EPAC antagonism has been explored as a broad-spectrum antiviral strategy, while selective EPAC activation with cAMP analogs has been found to increase virus replication and enhance therapeutic outcome of oncolytic virotherapy. However, systemic EPAC agonism bears risk of cardiovascular complications and may potentiate cancer progression.

Methods: A constitutively active construct of EPAC was encoded into an oncolytic vaccinia virus (VV) and screened using plaque assays, spheroid infections, and Transwell migration assays for its ability to enhance virus replication and spread. In vivo luminescence imaging, titering and immunohistochemical staining was used to measure virus dissemination in primary injected tumors and to track their spread to distal untreated tumors. The impact of the VV-EPAC virus on the immune landscape of MC38 tumors was investigated by flow cytometry, ELISPOTs and cytokine ELISAs, while its overall therapeutic efficacy was explored in MC38, CT26LacZ, and B16F10 models. Combinational synergy was also tested with capecitabine and oxaliplatin chemotherapy, as well as with partial surgical resection.

Results: The EPAC-expressing virus exhibited an increase in migrative ability both in cell culture and in vivo, due in part to remodeling of the actin cytoskeleton leading to intercellular nanotube-like structures and enhanced syncytia formation. It reduced tumor burden and increased survival in multiple colorectal cancer models and reshaped the tumor microenvironment by inducing angiogenesis and recruiting CD8+T cells. The EPAC-expressing virus also synergized with conventional chemotherapy and exhibited a remarkable therapeutic benefit when used together with surgical resection to treat a metastatic melanoma model. Despite the noted benefits that EPAC offers to virus and cancer growth, no significant increase in off-target replication, cytotoxicity, or disease progression was observed.

Conclusions: Altogether, the encoding of cellular signaling proteins into oncolytic viruses that modulate the intracellular and extracellular environments of tumors to create conditions favorable for virus replication and dissemination appears as a promising strategy to treat tumors and synergize with other conventional cancer therapies.

Background: Elevated levels of SPP1⁺ tumor-associated macrophages (TAMs) are associated with reduced CD8⁺ T cell infiltration and poorer prognosis in cancer patients, but direct evidence demonstrating a causal role for SPP1⁺ TAMs in excluding CD8⁺ T cells is still missing. The precise mechanisms by which SPP1-activated signaling pathways and macrophage-derived factors regulate CD8⁺ T cell trafficking remain poorly understood.

Methods: We established multiple tumor mouse models to study the function of macrophage SPP1 in the tumor environment, especially its role in the relationship between macrophages and CD8 T cells. We combined the single-cell (sc) RNA sequencing data of clinical tumor samples and tumor tissues from Spp1^{fl/fl-Lyz2-Cre} mice to identify the differences in SPP1-related genes and found that SPP1 could regulate the expression of CXCL9 and CXCL10 in macrophages. Through Western blotting, immunofluorescence staining, and flow cytometry analyses, we elucidated the mechanistic basis by which macrophage-specific SPP1 deficiency suppressed tumorigenesis.

Results: This study demonstrated that macrophage-derived SPP1 played a crucial role in suppressing CD8 T cell infiltration, promoting tumor progression, and diminishing the effectiveness of immune checkpoint inhibitor (ICI) therapy. Sc-RNA sequencing analysis revealed a marked increase in CD8 T cell populations within tumor tissues of Spp1^{fl/fl-Lyz2-Cre} mice. Furthermore, a negative correlation was observed between CD8 T cells and SPP1 macrophages in human colorectal cancer specimens. Genetic deletion of SPP1 in macrophages markedly enhanced tumor growth suppression in a manner dependent on CD8 T cell-mediated immunity. Mechanistically, SPP1 deficiency in macrophages led to elevated mitochondrial reactive oxygen species (ROS) production, resulting in the accumulation of cytosolic double-stranded DNA (dsDNA) fragments. This accumulated dsDNA activated the cGAS-STING pathway, leading to subsequent STAT1 phosphorylation. The enhanced STAT1 activity upregulated the expression of chemokines CXCL9 and CXCL10, thereby facilitating CD8 T cell recruitment into the tumor microenvironment.

Conclusions: Deletion of SPP1 in TAMs upregulates CXCL9/10 production by activating the ROS-DNA fragment/cGAS-STING/STAT1 pathway, thereby enhancing CD8 T cell infiltration, inhibiting tumor progression, and improving ICI treatment outcomes in tumors.

Background: Bispecific T cell engagers have demonstrated promising clinical progress in both hematologic malignancies and solid tumors; however, their therapeutic efficacy is still limited by multiple challenges including T cell anergy resulting from single-signal activation exclusively through CD3 engagement. As a critical co-stimulatory molecule, CD28 enhances T-cell functionality through synergistic interaction with the TCR-mediated primary activation signal, thus potentiating antitumor efficacy. Non-superagonistic CD28 bispecific antibodies, while enhancing antitumor efficacy, can minimize systemic toxicity. Kita-Kyushu Lung Cancer Antigen-1 (KK-LC-1), a cancer-testis antigen overexpressed in diverse malignancies, emerges as a promising target for tumor-specific immunotherapy. Herein, the development of a dual-signal T-cell engager strategy targeting KK-LC-1, using a non-superagonist CD28-based co-stimulatory mechanism, is of critical importance.

Methods: Based on the successful acquisition of the designed ankyrin repeat proteins targeting KK-LC-1 and CD28 through phage display technology (KD=8.985 nM and 7.43 nM), we designed two T cell engagers (KK-LC-1×CD3 and KK-LC-1×CD28). The tumor-specific binding activity of KK-LC-1 designed ankyrin repeat protein was verified by surface plasmon resonance, flow cytometry, confocal microscopy, and in vivo imaging. We then fused it with CD3 single-chain variable fragment and CD28-designed ankyrin repeat protein, respectively, to construct two T cell engagers. Their biological activities and antitumor efficacy were systematically evaluated both in vitro and in vivo (n=5) using flow cytometric analysis, confocal microscopy imaging, and bioluminescence quantification.

Results: T-cell engagers KK-LC-1×CD3 and KK-LC-1×CD28 were successfully engineered and demonstrated high binding affinity for both KK-LC-1-positive tumor cells and T cells. Co-administration of these engagers significantly augmented T-cell activation and antitumor efficacy (88% vs 66%, p<0.001) compared with KK-LC-1×CD3 monotherapy. In vivo, the combination suppressed tumor growth by 59.6% vs monotherapy (p<0.05) with enhanced intratumoral CD8⁺ infiltration (5.4-fold, p<0.001) and CD4⁺ infiltration (2.7-fold, p<0.001), while triple therapy incorporating PD-1×CTLA-4 bispecific antibodies extended median survival from 44 to 48 days (p<0.05).

Conclusions: We validated the feasibility of the KK-LC-1-targeted dual-signal T-cell engager strategy for the treatment of solid tumors and demonstrated that its combination with PD-1×CTLA-4 bispecific antibodies synergistically enhanced antitumor efficacy in preclinical studies.

Background: Although most studies of anticancer T-cell immunity focus on αβ T cells, γδ T cells are attracting increasing attention due to their involvement in antitumor immune responses in various cancer entities, including melanoma. While immune checkpoint blockade (ICB) using the antagonistic programmed cell death protein 1 (PD-1) antibodies nivolumab and pembrolizumab significantly improved the survival of patients with melanoma with distant metastasis, prognosis remains poor. PD-1 is not only expressed by αβ T cells but also by γδ T cells, making this numerically minor population of unconventional T cells, whose role in melanoma is still elusive, a target of ICB.

Methods: Here, we present a detailed γδ T-cell profiling study in late-stage melanoma at single-cell level using mass and polychromatic flow cytometry, T-cell receptor repertoire analyses and immunohistochemistry.

Results: Our analyses link high frequencies of peripheral Vδ1 T cells before the start of anti-PD-1 therapy to a significantly reduced overall survival. In these patients, the Vδ1 compartment is dominated by a late-differentiated senescent-like phenotype that is presumably unresponsive to therapy. This phenotype is less prevalent at the tumor site and analysis of RNA sequencing data revealed that the abundance of Vδ1 T cells within the tumor was positively associated with survival.

Conclusions: Our study suggests that Vδ1 T cells are associated with clinical outcomes, with a responsive subset expanding under ICB in patients where such a response remains possible. The observed clinical effects may be supported by the infiltration of these cells into the tumor, where they contribute to cancer immunosurveillance.

Background: While cancer vaccines have demonstrated promising clinical potential, their therapeutic efficacy against advanced tumors remains suboptimal, highlighting the critical need to elucidate resistance mechanisms and develop targeted solutions. We previously developed a stimulator of interferon genes (STING)-activating PC7A nanovaccine that elicits strong antitumor efficacy in multiple tumor models. In this study, we systematically investigated the mechanisms mediating nanovaccine resistance and provided targeting approaches to overcome this therapeutic barrier.

Methods: Vaccine efficacy at early stage and advanced-stage tumors was investigated in the B16-OVA melanoma model and TC-1 human papillomavirus-induced cancer model, with tumor microenvironment being comprehensively analyzed by flow cytometry. In a vaccine-resistant tumor, elevated immunosuppressive activity of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) was assessed through multi-analysis including surface marker staining, reverse transcription-quantitative PCR, and functional T cell-suppression assay. To investigate the CD300ld blockade strategy, we employed CD300ld-knockout (KO) mice for genetic ablation, or recombinant protein capable of competitive inhibition for pharmacological intervention. For clinical relevance assessment, we tested different cancer vaccine formulations at late-stage tumors in humanized-CD3000ld mice.

Results: In contrast to early stage vaccination, PC7A nanovaccine administration at the late tumor stage exhibited minimal therapeutic effects on tumor progression, while concurrently increasing PMN-MDSC infiltration and enhancing their immunosuppressive activity. KO of CD300ld, a critical immune suppressor on PMN-MDSCs, abolished both PMN-MDSC recruitment and their T-cell suppressive function, restoring the antitumor efficacy of PC7A vaccine in multiple advanced tumor models. Furthermore, in wild-type and CD300ld humanized mouse models, competitive blockade of CD300ld using recombinant extracellular domain proteins overcame resistance of advanced tumors to different cancer vaccine formulations.

Conclusion: Our results reveal that vaccination at the late tumor stage significantly augments the recruitment and immunosuppressive capacity of PMN-MDSCs, driving resistance of advanced tumors to cancer vaccines. The findings demonstrate PMN-MDSCs as critical mediators of vaccine resistance in advanced tumors and highlight modulation of PMN-MDSCs by CD300ld blockade as a promising strategy to enhance the therapeutic efficacy of cancer vaccines, particularly for patients with late-stage malignancies.

Although immune checkpoint inhibitors (ICI) have greatly improved outcomes in several cancer types, their use is also associated with immune-related adverse events (irAEs) that can impact any organ system and lead to significant morbidity and even mortality. Current approaches to treatment of irAEs largely rely on the use of systemic corticosteroids, which can compromise antitumor immune responses and oncologic outcomes. Prolonged use of systemic corticosteroids is also associated with its own set of toxicities. Thus, there is a critical need for steroid-sparing treatment approaches for irAEs.In this article, we review the literature for alternative therapeutic approaches for irAEs, which include targeted delivery (alternate routes of administration) of steroids (eg, budesonide) as well as systemic non-steroidal strategies using other mechanisms of action, such as integrin/cytokine blockade, antibody depletion, disease-modifying antirheumatic drugs and fecal microbiota transplant, among others. Many of these approaches have shown significant promise in their ability to induce a clinical response and improve symptoms, even in the setting of steroid-refractory or steroid-dependent irAEs. These approaches are being increasingly used as primary and secondary prophylaxis in patients at high risk of irAEs. Importantly, these strategies may mitigate steroid-associated toxicities, preserve antitumor immune responses and allow continuation of ICI after development of irAEs, hence enabling the full potential of ICI against cancer.

Background: Glioblastoma is an aggressive tumor with poor prognosis and limited treatment options due to its resistance to chemotherapy and radiotherapy, high heterogeneity, and ability to evade the immune system. Nevertheless, immunotherapy and oncolytic virotherapy are emerging as promising strategies. This study aimed to evaluate the therapeutic efficacy of an engineered oncolytic Herpes Simplex Virus for glioblastoma treatment.

Methods: We investigated the efficacy of R-115, a retargeted oncolytic Herpes Simplex Virus directed against the human epidermal growth factor receptor 2 (HER2) and engineered to express murine interleukin-12, in an immunocompetent glioblastoma model that recapitulates HER2 tumor heterogeneity. We tested the translatability and reliability of R-115 by assessing overall survival in HER2⁺ or HER2⁺/HER2^- mixed tumors treated with different schedules. We assessed the potential of the treatment to elicit an antitumor vaccination effect by rechallenging previously treated mice with HER2-negative cells in the absence of any further therapy. Additionally, we characterized both the immune and tumor components by analyzing immune cells' proliferation, activation and the resulting tumor cells reduction.

Results: R-115 exhibited potent cytotoxic and immune-stimulatory effects, significantly prolonging survival and eradicating tumors in approximately 25% of treated mice independently from tumor composition and treatment schedule. Furthermore, it induced long-term immune memory, enabling the eradication of secondary transplanted tumors, effectively acting as a tumor-agnostic vaccination. Notably, in addition to the direct oncolysis mediated by the virus, R-115 treatment induced an immune response even against HER2-negative glioblastoma cells, potentially via cross-presentation or epitope spreading.

Conclusions: Our findings candidate R-115 as a promising alternative to standard glioblastoma treatments and support further investigation to advance its clinical application.

Background: Stearoyl-CoA desaturase 1 (SCD1) is a key enzyme in fatty acid (FA) metabolism that catalyzes the addition of a cis double bond to palmitic and stearic saturated FAs, producing palmitoleic and oleic monounsaturated FAs, respectively. Interleukin (IL)9-secreting CD4⁺ T-helper lymphocytes (Th9) exert antitumoral activity in preclinical cancer models. In the present study, we evaluated the role of SCD1 in Th9 differentiation and their antitumoral properties.

Results: A specific monounsaturated FA profile is found in Th9 lymphocytes compared with Th1, Th2, Th17 and regulatory T cell (Treg) lymphocyte subsets and is correlated to the induction of SCD1 expression in mouse and human Th9 differentiated in vitro with TGFβ1 and IL4. The expression of SCD1 is also detected in tumor-draining lymph nodes and tumor-infiltrating Th9 lymphocytes of mice. The canonical Smad3 and non-canonical Pi3K members of the TGFβ signaling drive SCD1 expression in combination with IL4 during Th9 polarization. The invalidation of SCD1 gene expression or inhibition of its activity blocks Th9 differentiation by disrupting Smad2/3 activation. Furthermore, the lipidomic analysis between Th9 and Th9 invalidated for SCD1 gene or activity reveals a change in the FA profile, specifically a decrease in palmitoleic and oleic acids. Nevertheless, only oleic acid restores Th9 differentiation in CD4⁺ T lymphocytes invalidated for SCD1 gene or activity under TGFβ1 and IL4 polarizing conditions. Finally, invalidation of the SCD1 gene or its activity leads to the loss of Th9 antitumoral functions and promotes tumor growth through the production of TGFβ1.

Conclusion: We demonstrate that SCD1 contributes to Th9 differentiation and their antitumoral activity via the regulation of Smad2/3 signaling.

Background: Cergutuzumab amunaleukin (CA) is an immunocytokine comprising an anticarcinoembryonic antigen (CEA) linked to an interleukin-2 (IL-2) variant. CA does not bind to CD25 (IL-2 receptor α) and was designed to maintain the T and natural killer (NK) cell stimulatory effect, while avoiding stimulating effects on regulatory T cells (Tregs). In mouse models, CA previously demonstrated superior tumor targeting to CEA surface expression-positive (CEA+) tumors and increased CD8+ T cells and NK cell numbers in peripheral blood and tumor tissue when compared with wild-type IL-2. We present biomarker data from the first-in-human, open-label, multicenter, phase I, dose-escalation study investigating CA in patients with metastatic/unresectable CEA+ solid tumors (NCT02004106).

Methods: Patients received ascending doses of CA intravenously weekly (qw: 6/10/20 mg) or every 2 weeks (q2w: 10/20/30/40 mg). Flow cytometry determined absolute numbers/mL of CD4+ and CD8+ T cells, NK cells, macrophages/monocytes, Tregs, and B cells and their expression of activation and proliferation markers in circulation. Sequential pretreatment and on-treatment paired tumor biopsies were studied by flow cytometry, multicolor immunohistochemistry, and bulk RNA sequencing. Antitumor activity was used for correlative studies.

Results: Biomarker data were collected from 55 patients. After treatment, peripheral blood samples showed increased proliferating NK cells, CD8+ T cells, and CD4+ T cells, without an apparent dose effect. Levels of circulating soluble CD25 increased in patients with intermediate/high CA doses on-treatment; levels of cytokines, such as tumor necrosis factor, also increased with high CA dose levels. On-treatment tumor samples showed increases in total and proliferating CD8+ T cells as well as CD3+ perforin+ T cells but, importantly, not in Tregs. Notably, increases in the ratio of CD8+/CD4+ T cells were more pronounced for qw than for q2w dosing, while programmed death ligand-1-positive CD14+ cells increased, particularly for the q2w schedule. Higher on-treatment circulating levels of cytokines correlated with longer progression-free survival (PFS). Apart from the positive correlation with NK cell density, no other correlations between PFS and infiltrating immune cell populations in the tumor were observed.

Conclusions: CA-induced immune pharmacodynamic effects in peripheral blood and in the tumor microenvironment without preferential Treg cell activation in patients with metastatic/unresectable CEA+ solid tumors.

Trial registration number: NCT02004106; BP28920.

Background: Patients with non-small cell lung cancer (NSCLC) exhibit heterogeneous responses to immunotherapy (IT) with high resistance rates, highlighting the need for precise biomarkers of treatment outcomes.

Methods: In a prospective cohort study, we longitudinally assessed liquid biopsy samples from patients with NSCLC undergoing IT at four distinct time points (T1 pretreatment, T2 post-second cycle, T3 6 months, and T4 1 year). We profiled plasma-derived cell-free DNA methylation and extracellular vesicle-associated microRNAs from 79 patients with metastatic NSCLC treated with immune checkpoint inhibitors (ICIs). High-dimensional omics data were integrated using Multi-Omics Factor Analysis (MOFA2) to uncover latent molecular subtypes, which we termed MOFA-Derived Clusters (MDCs), independently established at baseline (MDC-T1) and post-second cycle (MDC-T2). Differential expression and methylation analyses, pathway enrichment, and immune phenotyping via flow cytometry were used to characterize the molecular and immunological landscape of each MDC. External validation was performed using independent NSCLC cohorts for miRNAs (Genova et al, 2024, n=54) and methylation (SMC Cohort, GSE119144, n=57).

Results: MDCs captured divergent survival outcomes and reflected biologically coherent processes including angiogenesis, cytoskeletal remodeling, and immune signaling. Projection of MDCs onto later time points (T3, T4) supported the temporal relevance of early molecular signatures. MDCs also displayed immunological correlates via circulating immune cell subsets. Importantly, MDC classifiers demonstrated consistent survival stratification in external cohorts, particularly MDC-T2.

Conclusion: This study defines a multiomic, liquid biopsy-based framework for molecular subtyping in NSCLC to manage ICI treatment. Our MDC signatures reveal clinically meaningful, treatment-informative biology and offer a path toward minimally invasive patient stratification in immuno-oncology.