Cancer Immunology, Immunotherapy

BackgroundTumour-associated macrophages (TAMs) play critical roles within the tumour microenvironment regulating immune evasion and therapeutic response. Previously, we have shown that the combination of Checkpoint kinase 1 inhibitor (CHK1i) with a subclinical dose of hydroxyurea (LDHU) reprograms the tumour immune microenvironment to a pro-inflammatory status. MethodsWe investigated a tumour-restricted Fcgr4 (Cd16.2) expressing macrophage population in multiple murine tumour models and the impact of CHK1i+LDHU on this population, using conventional and imaging flow cytometry as well as single-cell sequencing. ResultsTranscriptional profiling using CITE-seq and single-cell RNA sequencing reveals that Fcgr4 TAMs closely resemble Fcgr4- TAMs but display modest enrichment of interferon-associated and inflammatory gene programs, consistent with a functionally biased state rather than a distinct lineage. Importantly, we show that a highly tumour selective CHK1i+LDHU therapy shifts TAMs toward a more inflammatory phenotype while preserving dominant immunosuppressive features. Depletion of CSF1R macrophages enhanced CD8 T cell activation without influencing tumour growth but significantly augmented therapeutic efficacy of CHK1i+LDHU. ConclusionTogether, these findings define a novel TAM population and establish how targeted therapy reshapes, but does not fully overcome, TAM-mediated immune regulation.

BackgroundAntibody-mediated blockade of innate receptor-MHC-I interactions represents a promising strategy to enhance anti-tumor immunity, particularly against metastatic cancers resistant to conventional checkpoint inhibitors. In this study, we investigated the effects of the pan anti-MHC-I monoclonal antibody M1/42, which targets MHC-I interactions with Ly49, selectively expressed on murine NK cell subsets. MethodsWe administered M1/42 to mice and assayed the proliferation and activation immune cells. Anti-tumor activity of growth and metastasis of checkpoint inhibitor-resistant pancreatic ductal adenocarcoma (PDAC) and B16F10 melanoma were assessed, complemented by extensive cellular phenotypic and RNA expression analysis. Binding and cryo-electron microscopic (cryo-EM) and X-ray crystallographic structural studies of M1/42 complexed with the mouse MHC-I molecule, H2-Dd, examined the Ab interaction site in comparison with those of Ly49 inhibitory receptors. ResultsM1/42 administration in mice robustly unleashed the proliferation and activation of natural killer (NK) cells, memory CD4+ and CD8+ T cells, dendritic cells, and macrophages in both lymphoid and non-lymphoid tissues, independent of Fc{gamma} receptors. M1/42 significantly restricted the growth and metastasis of checkpoint inhibitor-resistant pancreatic ductal adenocarcinoma (PDAC) and B16F10 melanoma in the liver and lungs, accompanied by increased tumor infiltration of effector CD8+ T cells, reduction of T regulatory cells, and a pro-inflammatory cytokine milieu. The anti-tumor effects of M1/42 depend on NK cells and are associated with upregulation of genes involved in antigen processing, interferon gamma responsiveness, and Th1 cytokine production, while downregulating inhibitory PD1/11 signaling. Structural analysis indicated that the effect of M1/42 on Ly49/MHC-I interactions was not due to direct steric competition. ConclusionsCollectively, these findings demonstrate that M1/42 unleashes coordinated innate and adaptive immune responses, overcoming tumor-induced immunosuppression and resistance to checkpoint blockade. This approach represents a paradigm shift in cancer immunotherapy, offering potential for more effective treatment of metastatic cancers that evade immune surveillance through MHC-I modulation. KEY MESSAGESO_ST_ABSWhat is already known on this topicC_ST_ABSA pan anti-mouse MHC-I mAb (M1/42) blocks interaction with several NK inhibitory receptors (Ly49A or Ly49C) resulting in NK cell activation and anti-viral and anti-tumor responses in vitro and in vivo. Other pan anti-human MHC-I mAbs (DX17 and W6/32) function similarly, blocking LILRB inhibitory receptor interaction of myeloid cells and NK cells. These stimulate human immune cells in humanized mouse models. What this study addsThis study analyzes the effects of the pan anti-mouse MHC-I mAb on NK and myeloid cell activation in detail, in the absence of T or B cells, and independent of FcR interaction. Additionally we analyze several mouse models of metastatic tumor progression, indicative of the progressive activation not only of the innate immune response, but also adaptive responses. The molecular mechanism of the mAb blocking of inhibitory receptors is revealed by cryo-EM and X-ray structures of M1/42 Fab/MHC-I (H2-Dd) complexes. How this study might affect research, practice, or policyElucidation of the details of the inhibitory effects of the mouse pan anti-mouse MHC-I mAb provides not only a more advanced understanding of the murine model system, but suggests additional functional avenues to be explored using the parallel an anti-human MHC-I mAbs.

Background: Immune checkpoint inhibitors have transformed cancer treatment, yet a large number of patients fail to respond. Identifying molecular characteristics that predict response before treatment initiation remains an unmet need. Towards that end, this study presents a large-scale integrative analysis of existing single-cell and bulk tissue datasets, aimed at identifying predictive features while providing insights into their cellular origin and potential function within the tumor microenvironment. Methods: A stepwise analysis was performed using single-cell RNA-sequencing data from 60 melanoma patients at baseline, separated into discovery (n=41) and validation (n=19) sets. An integrated bulk transcriptomics dataset (n=128) from melanoma patients and a bladder cancer dataset (n=298) were used for further validation. Results: Integrative analysis of melanoma single-cell datasets revealed that responders exhibit distinct molecular profiles across multiple cell types compared to non-responders. Notably, these included downregulation of the TNFR superfamily and other immunosuppressive genes (TNFRSF18, TNFRSF9, TNFRSF4, LGALS1, BATF, IL12RB2, LINGO1, DUSP4, SDC4, VCAM1) in T-cells. By investigating the findings from the immune cell populations in the bulk tumor context, 13 transcripts were found to be consistently associated with response across all cohorts. These were differentially expressed in T-cells (SELL, EPB41, CD96, UHFR2, LINGO1, LGALS1), B-cells (ALDH5A1), NK cells (PLEC, PDGFRB) and Monocytes (TLR10, ST6GAL1, IKZF1, MPRIP). A predictive model based on these features effectively discriminated responders from non-responders in melanoma (AUC=0.73). The model maintained significant predictive power in an independent bladder cancer dataset (IMvigor210; AUC=0.64). Of high clinical relevance, it demonstrated enhanced performance in identifying responders among patients with low tumor mutational burden (AUC=0.75). Conclusion: Our study reveals pre-treatment molecular features related to immune-cancer crosstalk that are associated with response to immunotherapy. A 13-gene model demonstrates potential added clinical value in stratifying responders, particularly in patients with low tumor mutational burden, meriting further validation.

While prostate cancer (PC) is defined as immunologically cold, limiting the efficacy of immune checkpoint inhibitors, therapeutic vaccination targeting tumor-associated antigens represents an attractive strategy to promote disease control in low volume metastatic patients. The UV1 cancer vaccine is based on immunization with tripeptide fragments from human telomerase reverse transcriptase (hTERT) and a phase II clinical trial demonstrated induction of robust T cell response in men with de novo metastatic castration-sensitive prostate cancer (mCSPC). Comparison with long-term survival data of non-metastatic CSPC patients as reference showed that despite metastatic disease at diagnosis, UV1-treated patients who mounted an early vaccine-induced immune response achieved progression-free and overall survival comparable to non-metastatic patients. We examined biological determinants of clinical benefit following UV1 vaccination including tumor transcriptome and T cell receptor (TCR) profiling from circulating and tissue resident T-cells of the 22 men enrolled. Analysis of diagnostic and post-UV1 treatment biopsies revealed that low baseline exhaustion of T cells and higher CD8+ T cell abundance are associated with early immune response to the vaccine and longer survival. Moreover, we identified specific TCR motifs relative to early responders, that can indicate potential benefit from UV1 vaccination. These findings indicate that baseline intratumoral T cell exhaustion state and repertoire shape responsiveness to hTERT vaccination and long-term outcome. Overall, our study underlines how baseline immune profiling may be used as a companion biomarker to predict mCSPC patients most likely to benefit from therapeutic vaccination.

BackgroundPancreatic ductal adenocarcinoma (PDAC) is the paradigmatic immunotherapy-refractory cancer, with a 5-year survival of approximately 12% and minimal benefit from immune checkpoint blockade (ICB). The dominant mechanistic explanation classifies PDAC as a T cell-excluded "cold" tumor, implying that no functional anti-tumor T cells are available for checkpoint release. Whether this Block-strategy view is correct has not been re-examined under integrated evasion-framework analysis. MethodsWe applied a previously developed 16-module immune evasion framework to TCGA-PAAD (n=183), integrated with hub-cytokine analysis (IL-10/TGF-{beta}), Kv1.3-immune channelome data, and clinical trial mapping (12,007 trials). Single-cell validation used two independent PDAC cohorts retrieved through TISCH2: PAAD_CRA001160 (Peng 2019, 35 samples [24 PDAC + 11 adjacent normal], 57,443 cells) and PAAD_GSE154778 (Lin 2020, 16 samples, 14,953 cells), examined for CD8A, TOX, PRF1, KCNA3, and FAP expression by cell type. ResultsPDAC scored highest in CAF Wall (z=0.768) and Platelet Cloak (z=0.663) modules; strategy classification yielded Brake -- not Block -- driven by a positive KCNA3-survival relationship (HR=0.649, 95% CI 0.43-0.97, p=0.037). Single-cell qualitative analysis of TISCH2 violin plots showed that CD8 exhausted T cells (CD8Tex) carried (i) high CD8A, (ii) the highest TOX expression among annotated cell types, (iii) preserved PRF1, and (iv) high KCNA3 expression. FAP was strongly localized to fibroblasts (peak [~]3.0 vs. <0.5 elsewhere). The pattern was reproduced in the second cohort. The optimal three-module attack (MHC restoration + CAF disruption + VEGF blockade) suppressed 10 of 16 evasion modules in silico (62.5%); zero of 370 PDAC immunotherapy trials test this combination. ConclusionsPDAC may not be T cell-cold but T cell-trapped: CD8 T cells with intact Kv1.3 channels appear immobilized behind a FAP-positive cancer-associated fibroblast wall. ICB monotherapy is mechanistically insufficient because the brake is engaged on T cells that cannot reach the tumor. The framework predicts that triple-targeted intervention -- checkpoint release + CAF wall disruption + vascular normalization -- is the minimum effective strategy. This is a hypothesis-generating computational analysis; prospective experimental and clinical validation are required.

Immune checkpoint inhibitors (ICI) have revolutionized cancer therapy, yet response rates remain suboptimal across many solid tumors, and resistance mechanisms, particularly those involving glycans, are not fully understood. Recent studies have identified sialic acid-containing glycans and their interactions with Siglec receptors on tumor-associated macrophages as an important contributor to immune suppression within the tumor microenvironment (TME). Targeting this sialic acid-Siglec axis by glycan engineering with sialidases and other glycosidases has shown therapeutic potential in preclinical models. However, safe and effective delivery of sialidases to tumors remains a challenge. Here, we present a novel approach using adeno-associated virus (AAV)-mediated therapy to deliver sialidases (AAVSia) and other glycosidases, including fucosidase, directly to the TME. Intratumoral administration of AAVSia in mouse models resulted in significant tumor growth reduction, enhanced survival, and robust systemic antitumor immunity through improved cross-presentation and dendritic cell activation. Furthermore, combining local sialidase expression with fucosidase treatment and classical PD-1 blockade allowed a synergistic effect, amplifying antitumor response. Our findings highlight the therapeutic promise of glycoengineering the TME using local delivery systems and support the development of combination strategies to overcome glycan-mediated resistance in cancer immunotherapy. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=129 SRC="FIGDIR/small/720097v1_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@dc9d72org.highwire.dtl.DTLVardef@1e4e455org.highwire.dtl.DTLVardef@4a8f93org.highwire.dtl.DTLVardef@11813a3_HPS_FORMAT_FIGEXP M_FIG C_FIG

Abstract Introduction: MET tyrosine kinase (TKI) therapy has improved outcomes in patients with non-small cell lung cancer (NSCLC) harboring MET alterations. However, primary and acquired resistance ultimately limits durability of response. This study evaluated the safety and efficacy of the MET inhibitor capmatinib with the MEK inhibitor trametinib in patients with metastatic MET-driven NSCLC who had progressed on prior treatment with at least one MET inhibitor. Methods: A multicenter phase I study evaluated capmatinib in combination with trametinib in patients with advanced stage NSCLC harboring activating MET alterations and prior exposure to at least one MET TKI. A 3+3 dose-escalation design was employed to assess safety and tolerability of the combination. Results: Three patients (n = 3) were enrolled in the study and completed a median of 3 cycles of therapy. Dose-limiting toxicities, including rash, edema, and nausea, necessitated dose reductions in the first two patients and initiation of the third patient at a lower dose level. Ultimately, all patients discontinued therapy due to treatment-related adverse events. The study was terminated early due to poor accrual and TRAEs. No radiographic objective responses were observed. Conclusions: In this phase I trial, capmatinib plus trametinib was associated with significant treatment-related adverse events and treatment was discontinued in all participants. Based on these findings, further investigation of this combination of MET and MEK inhibitors is not recommended.

BackgroundMesothelioma (Me) is an aggressive cancer with limited response to conventional therapies. The tumors harsh microenvironment contributes to immune escape and therapy resistance and the effects of ICIs on Me are still unclear. Adenosine, an immunosuppressive molecule produced from AMP by the enzyme CD73, accumulates in hypoxic tumor areas. Elevated CD73 and adenosine receptor A2B (A2Br) levels on Me cells are linked to worse patient outcomes, indicating their important role in disease progression and potential as targets for treatment. AimThis study characterizes the Me-ME (micro environment) and evaluates the efficacy of TT-4 (A2B inibitor) and AB680 (CD73 inibitor), alone or with aPD-1, using 3D models in vitro and in vivo. MethodsCD73 and A2B receptor levels were quantified in tumor and normal samples using qRT-PCR and IHC. Cells lines were treated with CoCl2 to mimic hypoxia, then CD73, A2Br and related markers were analyzed. MSTO-211H and REN cells were silenced for CD73, grown as spheroids and adenosine release was measured. Co-culture spheroids of MSTO-211H and Jurkat cells were treated with AMP and CD73 inhibitor, then analyzed for viability and immune markers. An orthotopic Me model was established by injecting AB1-B/c-LUC cells and monitored by in vivo imaging. Proteomic analysis of spheroids was conducted to identify proteins and pathways involved. ResultsHypoxia boosts CD73 and A2Br expression in Me cells, leading to adenosine production via CD73. In 3D co-cultures, AB680 lowered Me cell viability and enhanced activation of Jurkat T cells. In mice, combining aPD-1 therapy with A2Br or CD73 inhibitors strongly reduced tumor growth. Proteomics identified 93 proteins influenced by adenosine signaling through A2B. ConclusionTargeting the adenosine pathway alongside PD-1 blockade offers a promising new immunotherapy strategy for Me.

Glioblastoma (GBM) is the most common and lethal primary malignant brain tumor in adults, with median survival remaining approximately 12-15 months despite aggressive multimodal therapy. Therapeutic resistance and tumor recurrence are driven in part by limited drug penetration across the blood-brain barrier (BBB) and the persistence of brain cancer stem cells (BCSCs), highlighting the need for brain-penetrant therapeutic platforms capable of achieving sustained intratumoral delivery. Here, we developed a dendrimer-based nanotherapeutic by conjugating metformin to a fourth-generation hydroxyl-terminated polyamidoamine dendrimer (P4-MET) to enhance intracranial bioavailability and therapeutic efficacy in GBM. P4-MET exhibited favorable pharmacokinetic properties, including prolonged retention within the tumor microenvironment, and demonstrated enhanced cytotoxicity against GBM cell lines relative to free metformin (f-MET). Mechanistical studies with transcriptomic profiling by RNA sequencing revealed distinct treatment-associated molecular signatures, identifying BOLA2B as the most significantly differentially expressed gene between treatment groups. Specifically, BOLA2B expression was markedly elevated in f-MET-treated cells but not so following P4-MET treatment. Given the established association of BOLA2B with mTORC1 signaling and GPX4-mediated ferroptosis resistance, these findings suggest that P4-MET may, at least in part, enhance therapeutic efficacy by modulating ferroptosis-associated pathways. In orthotopic GBM models, combination treatment with P4-MET and radiotherapy (RT) significantly prolonged overall survival and increased tumor cell death compared with either monotherapy alone, consistent with a synergistic radiosensitizing effect. Importantly, P4-MET demonstrated minimal systemic toxicity, supporting its favorable therapeutic index and translational potential. Collectively, these findings establish P4-MET as a brain-penetrant nanomedicine platform that improves metformin delivery, modulates ferroptosis-related signaling networks, and potentiates radiotherapeutic response in GBM. This study highlights the potential of dendrimer-enabled metabolic nanotherapies to overcome therapeutic resistance in malignant brain tumors.

Immune checkpoint inhibition (ICI) is clinically active against multiple cancers, including urothelial cancer at the non-muscle invasive, muscle-invasive, and metastatic stages. Despite this, large numbers of patients experience disease progression and relapse after treatment with ICI-containing regimens. Tumor antigen-specific T cells are critical to ICI response, however few studies have evaluated the breadth and magnitude of tumor antigen-specific T cell responses with ICI therapy. In this study, we mapped the tumor antigen immunodominance hierarchy in the BBN963 model of murine basal-like bladder cancer for endogenous tumor neoantigens expressed physiologically. We used a high-throughput matrixed ELISpot assay to detect CD8+ T cell responses to predicted BBN963 tumor antigens derived from multiple mutational genomic sources. We found CD8+ T cell responses were directed against a subset of tumor antigens forming a stable and reproducible immunodominance hierarchy across individual mice. Treatment with anti-PD-1 or anti-CTLA-4 did not substantially reshape this hierarchy or broadly shift dominant responses to previously defined subdominant epitopes. Predicted peptide MHC binding stability and affinity was associated with antigen immunogenicity. Cancer-testis antigens, endogenous retroviral antigens, and SNV-derived tumor antigens that were immunogenic were found across tumor subclones. By diversifying the immunogenic antigen repertoire beyond SNVs, we achieved nearly 100% tumor subclone coverage, suggesting that broader antigen selection could help immunotherapy target more tumor subclones. In conclusion, this study supports the stability of the immunodominance hierarchy under ICI therapy and a role for broadening antigen discovery to multiple expressional sources in immunotherapy design.

Defining the genetic and cellular programs that allow solid tumours to evade immune control requires preclinical models that preserve the complexity of the human tumour immune microenvironment. Most available systems capture only part of this biology. Organoid cultures and ex vivo tumour fragments can retain patient-derived tumour architecture and associated immune cells, but immune populations are typically maintained only for short periods. These models also cannot capture antitumour immune responses in the physiological setting of a living organism. Patient-derived xenografts propagated in humanized mice offer a potential path to overcome these limitations by combining patient-derived tumour tissue with a reconstituted human immune system. However, few studies have systematically tested whether these models reproduce the diverse immune cell phenotypes present in the parental tumours from which they are derived. This has limited their use for studying tumour-intrinsic mechanisms that shape immune composition and promote immune evasion. To address this gap, we profiled tumour-infiltrating, splenic, and bone marrow immune cells from ovarian, head and neck, and renal PDX models propagated in CD34+ hematopoietic stem cell (HSC)-derived huNOG-EXL mice expressing human IL-3 and GM-CSF. By comparing tumours grown across distinct HSC donor backgrounds with their matched primary tumour samples, we found that tumour-intrinsic factors are a dominant determinant of immune composition in humanized PDX tumours. Across models, these immune infiltrates generally resembled those of the corresponding parental tumours. These findings support humanized PDX models as a platform for functionally interrogating tumour-intrinsic drivers of immune composition and immune evasion in solid tumours.

Dendritic cells (DCs) are central orchestrators of antitumor immunity. Several DC subsets--including conventional type 1 (cDC1), conventional type 2 (cDC2), plasmacytoid DCs (pDCs), and mature DC populations--play distinct roles in immune surveillance, tumor control, immunotherapy response and prognosis. Recent findings suggest that cDC1 are spatially closed to CD8 T-cell and contribute to tertiary lymphoid structure formation in lung cancer. However, how other DC subsets interact with cDC1 to shape the tumor microenvironment (TME) remains largely unknown. Here, we analyzed the spatial distribution of major DC subsets, including cDC1, cDC2, mature DC and pDC, together with CD8 T cells in a cohort of anti-PD1-treated NSCLC patients and we deciphered the corresponding immune microenvironment behavior by paired transcriptomic analysis. We found that, while other DC subsets populated the stroma, cDC2 were localized both in the stroma and in tumor nests. Moreover, unlike other DC subsets, cDC2 abundancy did not affect ICB response both at transcriptomic and in situ analysis. We described spatial organization of DCs in megaclusters characterized by distinct proportions of DC subsets. Patients enriched in megaclusters involving variable proportion of pDC, cDC1 and mature DC, exhibited pro-inflammatory transcriptomic programs while those enriched in cDC2-based megaclusters showed limited immune activation features. Globally, DC in lung cancer were structured around three distinct DC spatial patterns, namely cDC1-driven, cDC2-driven and DC-Scattered, each defined by unique compositions of DC megaclusters, immune features and pathways activation profiles. Among them, the cDC1-driven pattern was associated to prolonged anti-PD1 response in two independent cohorts.

BackgroundTrained immunity is a durable functional reprogramming of innate immune cells characterized by enhanced responsiveness upon secondary challenge. While metabolic rewiring and epigenetic remodeling are well-established features of this process, the contribution of ubiquitin-mediated post-translational regulation remains poorly defined. MethodsWe performed an integrative analysis of publicly available human transcriptomic datasets derived from monocytes, macrophages, and PBMCs exposed to established training stimuli ({beta}-glucan, Bacillus Calmette-Guerin [BCG], and hemin-{beta}-glucan) followed by secondary stimulation. A curated panel of deubiquitinating enzymes (DUBs) and E3 ubiquitin ligases with established immune functions was analyzed for differential expression. Gene Ontology (GO) and KEGG pathway enrichment analyses were conducted to evaluate higher-order convergence across independent datasets. ResultsAcross multiple trained immunity models, we identified reproducible transcriptional remodeling of ubiquitin-modifying enzymes. USP25, OTUB1, and TRIM25 were consistently upregulated following restimulation, whereas several chromatin- and cytokine-regulatory DUBs--including USP3, USP4, USP7, USP16, MYSM1, and USP38--were downregulated. Normalization to RPMI-restimulated controls reduced many activation-associated signals; however, USP25 remained persistently elevated, suggesting a stable training-associated signature. Pathway enrichment analysis independently demonstrated significant engagement of ubiquitin-related functional categories across datasets, supporting coordinated reorganization of ubiquitin regulatory networks. ConclusionThese findings identify selective transcriptional remodeling of the ubiquitin- proteasome system as a recurring feature of trained immunity. Integrating ubiquitin signaling into the established metabolic-epigenetic framework expands the conceptual model of innate immune memory and suggests that ubiquitin-modifying enzymes function as modulatory rheostats shaping immune amplitude and stability. Future functional and proteomic studies are required to determine whether these transcriptional signatures directly mediate trained immunity phenotypes.

Lung is a major site of metastases for many primary cancers associated with poor outcomes. A central challenge in cancer immunotherapy is overcoming tumor immune evasion, which limits effective antitumor responses. Here, we investigated whether combinatorial mRNA-encoded cytokine therapy can overcome tumor immune evasion by coordinately engaging innate and adaptive immunity, using murine models of pulmonary metastases. We employed intravenously administered cationic nucleoside-modified mRNA-lipoplexes (RNA-LPX) for targeted delivery of mRNA-encoded cytokines to the lung. The cytokine mix containing interferon-, half-life extended interleukin (IL)-7, and a half-life extended IL-2 variant with reduced CD25-binding modulated the tumor immune microenvironment resulting in a potent and broad anti-tumor response and prolonged survival with good tolerability at the conditions tested. Using cell depletion experiments, we demonstrated that both T and natural killer (NK) cells are crucial mediators of the observed anti-tumor efficacy of the cytokine RNA mix, which induced activation and effector function of NK and T cells, coupled with reduced regulatory T cells (Treg) numbers and Treg activation in the lung. Importantly, antitumor efficacy was maintained in models of impaired antigen presentation, including loss of an immunodominant tumor antigen and MHC class I deficiency, where NK cells served as the primary effectors. The cytokine RNA mix induced immune cell activation in the primary human lung tumor culture, suggesting potential for translational application. Collectively, these findings demonstrate that combinatorial cytokine therapy can drive both antigen-dependent and antigen-independent tumor control for the treatment of lung metastases.

BackgroundObesity significantly increases the risk of prognosis and clinical outcomes in pancreatic ductal adenocarcinoma (PDAC). While research on the interactions between obesity and the tumor microenvironment (TME) is mostly confined to a few interactions at a time, leaving a gap in the comprehensive understanding of obesity-driven PDAC. We set out to develop a cell-type-resolved model of obesity-driven PDAC using bulk transcriptomic data to investigate TME changes. MethodsWe conducted an integrated transcriptomic analysis of PDAC patients from the CPTAC-3 cohort (n=140) stratified by BMI. A custom immune and stromal functional gene signature database covering 65 cell types was constructed, followed by LLM-assisted review, overlap control, and validation. BayesPrism deconvolution using matched single-cell references was used to derive expression profiles for each cell type. Stabl, a machine-learning algorithm, was used to identify BMI-associated signatures. Bayesian hierarchical modeling, using both continuous and categorical BMI change, was applied to estimate effect sizes and assess the statistical credibility of the signature changes using the 95% Highest Density Interval (HDI) excluding zero. Virtual multiplex immunofluorescence was generated from whole-slide H&E images using gigaTIME to assess the spatial manifestation of BMI-associated TME changes in tissue ResultsBulk pathway analysis showed that ECM homeostasis and primary immunodeficiency pathways deteriorated with increasing BMI. However, Bayesian modeling revealed cell-type-specific, non-linear dynamics. Stromal populations in overweight (OW) individuals were altered, with changes in ECM synthesis and inflammatory signaling that stabilized rather than intensified during obesity. Immune compartments also showed diverse trajectories: CD4+ T cells remained functional in OW but collapsed in obesity; CD8+ T cells progressed linearly from activation to chronic exhaustion. NK cells exhibited non-monotonic behavior, and monocyte and B cell lineages became impaired prior to clinical obesity. Cell-cell interaction analysis showed a shift from a T cell and dendritic cell-centric adaptive interactome in normal weight patients to a neutrophil-dominated inflammatory network in OW. Spatial analysis showed stromal-trapped CD8+ T cells were compressed closer to the tumor boundary with rising BMI. ConclusionsOverweight status represents a critical tipping point in tumor microenvironmental reprogramming, challenging linear models of obesity-associated immune modulation and suggesting that early metabolic interventions may prevent PDAC functional deterioration. Model is available at https://obese-pdac-model.streamlit.app/ O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=138 SRC="FIGDIR/small/721695v1_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@b1c8cdorg.highwire.dtl.DTLVardef@1f61b7forg.highwire.dtl.DTLVardef@876c60org.highwire.dtl.DTLVardef@dc32b2_HPS_FORMAT_FIGEXP M_FIG C_FIG

BRAF-targeted therapy (BRAFi/MEKi) and immune checkpoint blockade (anti-PD-1/anti-CTLA-4) have transformed the treatment of BRAF-mutant metastatic melanoma. While most patients who respond to targeted therapy eventually progress, a subset derives durable benefit, and biomarkers to identify this subset would inform optimal treatment selection. In this study, we analyzed pre-treatment tumor samples from a clinically annotated cohort of 155 patients with BRAF-mutant metastatic melanoma treated with first-line BRAFi/MEKi and followed for up to five years. We stratified patients into durable responders (PFS [&ge;] 24 months) and rapid progressors (PFS < 6 months with progression) and found that a global metric of tumor genomic heterogeneity, rather than individual gene alterations, distinguished these groups. Combining genomic heterogeneity with baseline tumor burden (e.g., lactate dehydrogenase (LDH) or radiographic lesion dimensions), we developed a parsimonious model that predicted durable responders with high precision and specificity. Notably, the analogous population of patients treated instead with immunotherapy were not durable responders, suggesting that the selected predictors of durable responders are targeted therapy specific. Spatial profiling of a subset of pre-treatment biopsies (n = 47) demonstrated that high intratumoral, but not peritumoral, CD8+ T-cell infiltration correlated with prolonged survival on BRAF-targeted therapy and served as an independent predictive factor when considered with genomic heterogeneity and features of clinical tumor burden. Together, these findings highlight the distinct baseline intrinsic and extrinsic features underlying durable response to BRAF-targeted therapy and support their potential implication in guiding treatment selection for patients with BRAF-mutant metastatic melanoma. One-Sentence SummaryIntegrated clinical, tumor genomic, and immune microenvironmental features predict durable responses to BRAF-targeted therapy.

BackgroundThis study evaluated the safety and efficacy of primary resection and anastomosis (PRA) for colovesical fistula (CVF) of diverse etiologies and identified independent prognostic factors for oncological outcomes. MethodsWe retrospectively analyzed 112 CVF patients (2017-2024) undergoing PRA with or without a defunctioning stoma, comparing clinical outcomes across benign and malignant cohorts. ResultsBenign etiologies accounted for 33.0% (n=37) (colonic diverticulitis (n=19, 51.4%), Crohns disease (n=14, 37.8%), and iatrogenic injury (n=4, 10.8%)), all underwent PRA with partial cystectomy, achieving zero mortality and no recurrence. Malignancies (67.0%) primarily included colorectal adenocarcinoma (sigmoid colon cancer (n=44, 58.7%) or rectal cancer (n=31, 41.3%)). Within the malignant cohort, radical cystectomy (n=15) was strictly necessitated by advanced disease features, including distal tumor location and extensive bladder wall invasion (80.0% vs 36.7%, P=0.003). Consequently, this advanced cohort experienced longer operative times (589 vs. 289 min), higher blood loss (600 vs. 100 mL), increased morbidity (80.0% vs. 20.0%, P<0.001), and shorter disease-free survival (DFS) (8 vs. 20 months, P=0.008) compared to those amenable to partial cystectomy (n=60). Crucially, multivariate analysis identified perineural invasion (PNI) (HR: 3.83, 95% CI: 1.49-9.84; P=0.005) as a critical independent predictor of recurrence, reflecting the impact of tumor biology over surgical extent. ConclusionsPRA is a definitive and versatile strategy for CVF. In malignant cases, bladder-preserving strategies are oncologically viable when R0 margins are achievable. Integration of PNI status and neoadjuvant therapy was essential for refining personalized multidisciplinary management.

Background: The development of personalised mRNA cancer vaccines holds considerable promise for oncology, yet a significant translational gap persists between neoantigen identification and the selection of therapeutically impactful targets. Current approaches predominantly prioritise human leukocyte antigen (HLA) binding affinity and immunogenicity, often overlooking the systems-level biological context of the target. This can inadvertently favour immunogenic but biologically peripheral peptides that exert limited influence on tumour signalling networks, thereby constraining vaccine efficacy. Furthermore, mRNA therapeutics must satisfy additional design requirements, including favourable codon usage and favourable secondary-structure stability, which directly affect in vivo translation and half-life. A unified computational framework that integrates neoantigen discovery with network biology is therefore critically needed. Results: Here, we present PimRNA, a Priority index (Pi)-centric computational medicine framework that bridges this gap by unifying neoantigen identification, mRNA sequence optimisation, and gene interaction network analysis. First, high-confidence tumour-specific HLA class I and II neoantigenic peptides are identified from paired tumour-normal genomic and tumour transcriptomic data using NeoDisc. Second, the coding sequences of these peptides are optimised for stability and translational efficiency with LinearDesign, yielding a core set of neoantigen-encoding mRNAs. Third, a random walk with restart algorithm is applied to a knowledgebase of gene interactions to identify peripheral genes exhibiting significant network connectivity to core genes, generating a gene-predictor matrix in which each gene is assigned an affinity score reflecting its network proximity to immunogenic neoantigens. These scores are consolidated into a single, unified priority rating (0-5) for each gene, followed by subnetwork analysis that reveals therapeutically relevant gene modules. Application of PimRNA to breast cancer and melanoma datasets demonstrates that it successfully selects high-confidence immunogenic neoantigen candidates embedded within biologically meaningful tumour-specific networks. Conclusion: PimRNA provides a systems biology foundation for mRNA vaccine design, moving beyond isolated immunogenicity to prioritise targets that are both highly presented and central to tumour-relevant biological networks. This framework offers a generalisable strategy for the rational discovery and prioritisation of mRNA therapeutics, significantly advancing the field of computational medicine towards personalised cancer vaccines.

BackgroundPrimary and secondary resistance to immune checkpoint blockade (ICB) remains a critical challenge in advanced melanoma. Oncolytic Viruses (OV) selectively lyse tumor cells while generating systemic anti-tumor immune responses with minimal side effects. Yet their clinical use is limited to refractory melanoma patients and are only given in combination with second-line ICB regimens. ICB can both help and hinder OV efficacy depending on the source of checkpoint interactions across the tumor-immune microenvironment (TiME). However, functional checkpoint interactions are typically inferred from gene or protein expression and rarely contextualized within myeloid- and antigen presenting cell-associated immune niches during OV therapy, despite these populations dominating melanoma TiMEs and serving as key regulators of anti-viral immunity. MethodsAn integrated multi-omics framework combining Nanostring GeoMx digital spatial profiling (DSP), COMET sequential immunofluorescence (seqIF) and functional oncology mapping (FuncOmap) was applied to melanoma patient tissues collected pre- and post-neoadjuvant Talimogene Laherparepvec (T-VEC) to characterize immune remodeling and directly quantify checkpoint interaction dynamics associated with pathologic responses to OV therapy. ResultsT-VEC induced broad lymphocyte- and myeloid-associated immune transcriptional activation across melanoma TiMEs; however, pathologic responses could not be defined by bulk transcriptomics or cellular deconvolution alone. COMET seqIF analysis identified that HSV-associated M1/APC-like tumor-associated macrophages (TAMs) were enriched in complete pathologic response (CR) tissues and were a major source of PD-1/PD-L1 interaction niches. While partial (PR) and non-pathologic response (NR) tissues retained melanoma-centered PD-1/PD-L1 interaction niches and were enriched for B cell and M2-like TAM populations. FuncOmap analysis indicated that post-T-VEC PD-1/PD-L1 interaction states were consistently elevated in tumor bed, but not in lymph node tissues, across all pathologic response groups. Suggesting that immune checkpoint interactions may benefit T-VEC therapeutic responses depending on their spatial and immune context relative to OV infection. ConclusionsThese findings highlight the importance of integrated transcriptomic and functional proteomic analyses for resolving the spatial distribution and functional status of immune niches during OV therapy. Resolving PD-1/PD-L1 interaction states to specific M1/APC-like TAM and B cell niches may define mechanisms of responses and resistance to OV therapy.

Anaplastic thyroid carcinoma (ATC) is one of the most lethal malignancies. Immune dysregulation is believed to play an important role in ATC. Here, we aimed to characterize the systemic inflammation and the function of circulating immune cells of patients with ATC. First, we retrospectively assessed biochemical parameters of patients with ATC and observed that high systemic inflammation correlated with worse survival. Next, we prospectively investigated the inflammatory proteome, single-cell peripheral blood mononuclear cell transcriptome and epigenetic changes. Circulating concentrations of proinflammatory cytokines were increased in ATC patients. This proinflammatory profile was apparent at the level of gene transcription and chromatin accessibility, especially in monocytes. These findings were substantiated by an increased capacity of peripheral blood mononuclear cells of ATC patients to produce IL-6, IL-8 and lactate. As IL-6 is known to promote tumor cell survival, we assessed its capacity to influence ATC cell proliferation. Blocking IL-6/gp130/Jak/STAT3 pathway inhibited proliferation of ATC cell lines in vitro. In conclusion, these findings show that ATC is characterized by inappropriate systemic inflammation and epigenetic and transcriptional reprogramming of circulating monocytes. Proinflammatory cytokines released by monocytes support survival and proliferation of ATC tumor cells, suggesting a therapeutic potential of targeting this pathway in ATC patients.