Journal for Immunotherapy of Cancer最新文献

Background: Global clinical programs based on TIGIT (T cell immunoglobulin and ITIM domain) blockade have been terminated due to inadequate clinical efficacy. New approaches are needed to increase the antitumor activity of anti-TIGIT-based immunotherapy.

Methods: Multiomics analyses, including single-cell RNA sequencing (scRNA-seq), single-cell TCR sequencing (scTCR-seq), and The Cancer Genome Atlas bulk RNA-seq, were performed to profile TIGIT and the costimulator CD226 expression and assess intratumoral regulatory T cells (Tregs) clonality, with validation by flow cytometry in murine and patient-derived tumor-infiltrating lymphocytes. The therapeutic efficacy of anti-TIGIT antibodies (αTIGIT), including αTIGIT-IgG1-wild-type (WT), αTIGIT-IgG1-WT with enhanced antibody-dependent cellular cytotoxicity (ADCC) activity (αTIGIT-IgG1-ADCC), αTIGIT-IgG4-WT, and tiragolumab, was evaluated in MC38 tumors-inoculated humanized TIGIT knock-in mice (Tigit^h/h , Tigit^h/m ). Tumor microenvironment alterations were analyzed using flow cytometry and scRNA/TCR-seq. Antibody binding affinity and ADCC activity were assessed via biolayer interferometry and in vitro ADCC assays. Safety profiles were examined in a murine immune-related adverse events model through growth monitoring, survival analysis, and histopathological evaluation.

Results: Using mouse models and clinical sample analysis, we identified a population of TIGIT^high CD226^- clonally expanded intratumoral Tregs as a major barrier limiting the ability of TIGIT blockade to enhance effector cell function. αTIGIT-IgG1-ADCC specifically targeted and eliminated the TIGIT^high CD226^- clonally expanded Treg subset, resulting in a marked improvement in antitumor efficacy compared with WT and clinically unsuccessful αTIGIT. Mechanistically, removal of these Tregs through αTIGIT-IgG1-ADCC relieved their suppression of stem-like CD4⁺ T cells, facilitating their differentiation into T helper cell 1 (Th1) effector cells. Th1-derived interferon-gamma (IFN-γ) further enhanced the functionality of tumor-infiltrating CD8⁺ T cells. Importantly, the presence of clonally expanded intratumoral Tregs and the suppression of stem-like CD4⁺ T cells correlated with poor immunotherapy response in patients with non-small cell lung cancer.

Conclusions: Targeted elimination of clonally expanded intratumoral Tregs is essential to unlock the full therapeutic potential of αTIGIT. These novel findings provide a key rationale and strategic direction for overcoming the limitations of current αTIGIT-based cancer immunotherapy.

Background: Most colorectal cancers (CRCs) are mismatch repair-proficient (pMMR) and microsatellite stable (MSS), and they respond poorly to immune checkpoint inhibitors (ICIs). Radiotherapy (RT) can promote antitumor immunity but may also trigger adaptive immune suppression through checkpoint upregulation, providing a rationale for combination therapies.

Methods: We integrated transcriptomic analyses from The Cancer Genome Atlas and Gene Expression Omnibus cohorts-annotated for microsatellite instability (MSI)/MMR status-with single-cell RNA-sequencing data from the Human Colorectal Cancer Atlas. Mechanistic and translational experiments were conducted using CT26 (MSS/pMMR) and MC38 (microsatellite instability (MSI)-high/mismatch repair-deficient (dMMR)) mouse models, patient-derived organoid (PDO)-immune co-cultures, and clinical CRC specimens. Assessments included multicolor flow cytometry, immunohistochemistry/immunofluorescence, bulk RNA-sequencing, and immune profiling.

Results: HAVCR2 (T cell immunoglobulin and mucin-domain containing-3 (TIM-3)) and LGALS9 (galectin-9) were broadly expressed in CRC, remaining relatively high in MSS/pMMR tumors compared with most other checkpoints. In CT26 tumors, RT preferentially increased programmed cell death protein 1 (PD-1) and TIM-3 co-expression on intratumoral CD8⁺ T cells and natural killer (NK) cells, whereas these changes were weaker and less consistent in MC38 tumors. The addition of TIM-3 blockade to RT plus programmed death-ligand 1 (PD-L1) blockade produced the most durable antitumor activity in CT26 tumors, improving primary tumor control, abscopal effects, and protection against tumor rechallenge. In PDO-immune co-cultures, pMMR PDOs showed a consistent incremental benefit when TIM-3 blockade was added to RT+PD-L1 blockade, whereas this added benefit was less consistent in dMMR PDOs. In clinical datasets and specimens, RT-containing treatment was associated with increased T-cell infiltration and higher TIM-3/PD-1 signals; stereotactic body radiotherapy was accompanied by systemic immune alterations, including TIM-3 induction on circulating immune subsets. Across pan-cancer cohorts treated with ICIs, concomitantly high expression of HAVCR2 and PDCD1 correlated with an immune-activated transcriptional profile and improved clinical outcomes.

Conclusions: These findings identify TIM-3/PD-L1 as a context-dependent adaptive resistance axis following RT. The greatest incremental value of TIM-3 blockade was observed in MSS/pMMR settings, where RT more consistently increased PD-1 and TIM-3 co-expression on intratumoral CD8⁺ T cells and NK cells. Combining RT with dual TIM-3/PD-L1 blockade warrants further clinical evaluation for immunotherapy-refractory CRC.

Adoptive transfer of unmodified γδ T cells has shown limited clinical benefit, prompting a shift toward chimeric antigen receptor (CAR) engineering to enhance activation, persistence, and tumor specificity. CAR technology positions γδ T cells as promising carriers due to their innate-like cytotoxicity and HLA-independent recognition. Evidence from αβ CAR T-cell trials indicates that γδ CAR T cells can persist for months to years post-infusion, suggesting their potential contribution to long-term immune surveillance against cancer. Among γδ subsets, Vγ9Vδ2 T cells dominate peripheral blood and have been preferentially used for CAR engineering. Recent advances, however, enable the expansion of Vδ1 T cells, known for their tissue residency and resistance to exhaustion. In a key comparative study, Li et al benchmarked PSCA-targeted CARs in Vδ1, Vγ9Vδ2, and αβ T cells, showing similar short-term tumor control but distinct transcriptional and phenotypic programs. These findings highlight the need for subset-specific optimization of γδ CAR-T therapies. Early studies in hematologic malignancies could provide a practical proof of concept, before tackling the additional challenges of solid tumors. Such focused development may be essential to advance the γδ CAR-T field amid tightening industry investment.

Background: The complex tumor microenvironment (TME) of colorectal cancer (CRC), composed of diverse cellular components and dynamic interactions, constitutes a major barrier to effective immunotherapy and facilitates disease progression. There is a pressing need to elucidate CRC-intrinsic factors that induce the immunosuppressive TME. Here, we explored the role of homeobox D13 (HOXD13) in shaping the immune microenvironment of CRC and its contribution to immunosuppression.

Methods: The expression level of HOXD13 was assessed using quantitative real-time PCR, immunoblotting, and immunohistochemistry. The role of HOXD13 in CRC was investigated using orthotopic allograft models and azoxymethane/dextran sulfate sodium-induced spontaneous tumor models in intestine-specific HOXD13 knockout and knock-in mice. The immune landscape of the CRC microenvironment was characterized via flow cytometry and immunofluorescence.

Results: Our study revealed the upregulation mechanism of HOXD13 in CRC and its functional role in fostering an immunosuppressive TME. HOXD13 was upregulated in CRC, particularly in metastatic cases, and patients exhibiting high HOXD13 expression showed poorer clinical outcomes. Mechanistically, HOXD13 promoted M2-type polarization of tumor-associated macrophages (TAMs) and suppressed CD8⁺ T cells mediated antitumor immunity by transcriptionally upregulating amphiregulin (AREG) and paired immunoglobulin like type 2 receptor alpha (PILRA) in CRC cells. Concurrently, transforming growth factor beta 1 released from M2-polarized TAMs further augmented HOXD13 expression in CRC cells via activation of the Smad2/3 signaling pathway. This reciprocal interaction formed a self-reinforcing loop that sustained immunosuppression and thereby accelerated tumor progression. Notably, combined inhibition of AREG and programmed cell death ligand 1 effectively disrupted this crosstalk, restored antitumor immunity, and ultimately suppressed CRC progression.

Conclusions: Our study identified HOXD13 as a pivotal regulator in the establishment of an immunosuppressive TME and suggested that targeting the HOXD13 signaling axis represents a promising strategy to sensitize CRC to immunotherapy.

This Highlight describes a key observation where serotonin transporter (SERT) was shown to suppress CD8⁺ T cell antitumor responses via depletion of intratumoral 5-HT. While selective serotonin reuptake inhibitors (SSRIs)-among the most widely used antidepressants-significantly inhibit tumor growth and enhance T cell-mediated antitumor immunity in both mouse models and human xenografts, showing remarkable synergy with anti-PD-1 therapy. These findings emphasize the importance of intratumoral 5-HT signaling, establish SERT as an immune checkpoint, and identify SSRIs as promising candidates for cancer immunotherapy.

Therapeutic vaccines include DNA, mRNA, protein-loaded antigen-presenting cell, synthetic long peptide (SLP) and recombinant virus platforms. Only two therapeutic vaccines for neoplastic disease were approved by the Food and Drug Administration in the past 40 years: sipuleucel-T, approved in 2010 for hormone-resistant metastatic prostate cancer and targeting prostate acid phosphatase; and zopapogene imadenovec, approved in 2025 for recurrent respiratory papillomatosis, a rare, non-malignant but often invalidating disease caused by human papillomavirus (HPV) type 6 or type 11. In the last decade, DNA, mRNA and SLP vaccines directed against mutation-derived neoantigens have shown strong immunogenicity for T cells and clinical activity with or without additional immune checkpoint inhibition. Vaccine monotherapy is effective in premalignant disorders caused by high-risk HPV16 and virus-negative colonic polyps. Treatment of bulky or recurrent/metastatic (R/M) disease requires combination with surgery and/or chemotherapy or combination with an immune checkpoint inhibitor such as PD-1 blocker. In a recent study, adjuvant treatment with neoantigen-specific mRNA vaccine plus PD-1 blocker led to less melanoma recurrence than PD-1 blocker alone. In another randomized study, patients with R/M HPV16+ head and neck cancer only benefited from the combination of HPV16-specific SLP vaccine and a PD-1 blocker if they had high pretreatment PD-L1 biomarker expression in cancer tissue. Increasingly, biomarker-guided therapy is recommended.

Background: Immune checkpoint inhibitors (ICIs) improve survival in advanced non-small cell lung cancer (NSCLC), yet current biomarkers such as programmed death-ligand 1 (PD-L1) expression and response criteria (Response Evaluation Criteria in Solid Tumors, RECIST, V.1.1) align poorly with long-term survival. Radiomics has been proposed as a source of novel biomarkers, but standard radiomic approaches suffer from limited biological interpretability and poor generalizability across treatment settings. We address these gaps by developing the Quantitative Vessel Tortuosity (QVT) score, a biologically interpretable imaging biomarker that quantifies tumor vascular complexity-a known mediator of immune evasion-from routine imaging. We hypothesized that QVT score would improve prognostication and enable treatment response monitoring in ICI-treated NSCLC, independent of current biomarkers.

Methods: This retrospective, multicenter study analyzed 1,301 CT scans from 682 patients with ICI-treated NSCLC. An automated pipeline segmented lesions and tumor-associated vasculature within each scan, extracting 910 QVT features measuring vascular shape and complexity. Unsupervised clustering of these features in a discovery cohort (N=375) was performed to identify fundamental vascular phenotypes. A continuous QVT score was then derived using regularized logistic regression to map patients along this phenotypic spectrum. QVT score was externally validated in ICI monotherapy (N=172) and chemoimmunotherapy (N=135) cohorts. In a longitudinal cohort (n=143), early on-treatment QVT score changes were evaluated for overall survival (OS) association.

Results: Two robust vascular phenotypes emerged in the discovery cohort: a highly vascularized, chaotic "QVT High" phenotype with poor post-ICI OS and a "QVT Low" phenotype with normalized vasculature and improved ICI outcomes. The continuous QVT score was prognostic for ICI monotherapy (HR=1.17 per 0.1 increase, p=0.0028) and chemoimmunotherapy (HR = 1.23 per 0.1 increase, p = 4.9×10⁻⁵). High QVT status remained prognostic for both treatments after adjustment for PD-L1 and clinical variables (adjusted HR range: 2.13-2.38, p≤0.002). Early decreases in QVT score during therapy, indicating vascular normalization, were associated with improved OS (HR=1.93, p=0.0022) independent of RECIST best overall response and tumor volume change.

Conclusions: QVT score is a novel, biologically interpretable imaging biomarker that quantifies vascular complexity. It enables automated, non-invasive prediction and monitoring of ICI outcomes by capturing treatment-induced vascular remodeling. Integrating QVT score into clinical decision-making and drug development can address critical gaps in precision oncology.

Relapse remains the primary cause of treatment failure and death in pediatric B-cell acute lymphoblastic leukemia (B-ALL). Novel therapeutic approaches are imperative for those who are refractory to blinatumomab and chimeric antigen receptor T (CAR-T) cell therapy. CAR-natural killer (NK) cells have emerged as promising candidates for novel cancer immunotherapies, with enhanced antitumor activity and low rates of adverse events. However, data on the efficacy of CAR-NK cells for treating pediatric relapsed/refractory B-cell acute lymphoblastic leukemia (R/R B-ALL) are lacking.We report a challenging case of a boy with relapsed B-ALL after blinatumomab who failed to respond to autologous CD19-targeted CAR-T cell therapy and mitoxantrone-based reinduction chemotherapy. The patient achieved a complete remission after donor-derived CD19-targeted CAR-NK cell infusion, experiencing a grade 3 immune effector cell-associated neurotoxicity syndrome (ICANS), which was completely controlled by timely treatment. Then, the patient received the same donor-derived hematopoietic stem cell transplantation (HSCT) and remains in complete remission for a year post-HSCT.Our case provides an example of the utility of CAR-NK cell therapy as a bridge to HSCT in treating pediatric R/R B-ALL, despite the occurrence of ICANS as a manageable toxicity.

Background: Leptomeningeal metastasis (LM) is a fatal complication of advanced cancer with limited therapeutic options and poor prognosis. Immune checkpoint inhibitors (ICIs) have shown promise in systemic disease, but intrathecal ICIs efficacy and immunological impact in LM remain unclear. Cerebrospinal fluid (CSF) proteomics may provide a unique window into the CNS immune microenvironment and enable response prediction.

Methods: We enrolled 62 patients with LM who received intrathecal pemetrexed (InPe) with or without ICIs (InPe+programmed cell death protein-1 (PD-1), InPe+PD-1+cytotoxic T-lymphocyte associated protein 4 (CTLA-4), InPe+PD-1+vascular endothelial growth factor (VEGF)). Matched CSF (pretreatment and post-treatment) and pretreatment serum samples were collected for high-content proteomic profiling using the Olink platform. Differential expression, pathway enrichment, and machine learning-based modeling were applied to identify treatment-induced changes and predictive biomarkers.

Results: Nearly half of the patients achieved clinical response. Post-treatment CSF showed enrichment of cytokine and chemokine signaling pathways, with a marked decrease in EGF. Adding PD-1 inhibitor restored immune cell function and upregulated interferon-γ. Compared with serum, CSF proteomic profiles provided superior predictive performance (area under the curve (AUC) 0.884 vs 0.780). A five-protein CSF signature (ADGRG1, CD28, CCL23, DCN, IL-15) achieved robust prediction (AUC 0.968 in InPe+PD-1 training cohort, 0.917 in InPe+PD-1+CTLA-4 validation cohort, and 1 in InPe+PD-1 subsequent validation cohort). ADGRG1 was significantly higher in non-responders at baseline (p=0.031) and decreased after treatment, and specific enrichment in dura-derived LM-associated macrophages, suggesting a macrophage-derived source and potential role in LM progression.

Conclusions: This study provides the first high-content proteomic atlas of intrathecal ICI therapy in LM, identifies intrathecal ICI therapy-specific immune remodeling in LM, and establishes a CSF-based predictive model with high accuracy. ADGRG1 represents a promising biomarker of treatment responsiveness and a potential mechanistic link between macrophage biology and LM progression.