Journal for Immunotherapy of Cancer最新文献

Background: Liver metastasis is highly aggressive and immune tolerant, and lacks effective treatment strategies. This study aimed to develop a neoantigen hydrogel vaccine (NPT-gels) with high clinical feasibility and further investigate its efficacy and antitumor molecular mechanisms in combination with immune checkpoint inhibitors (ICIs) for the treatment of liver metastases.

Methods: The effects of liver metastasis on survival and intratumor T-cell subpopulation infiltration in patients with advanced tumors were investigated using the Surveillance, Epidemiology, and End Results Program (SEER) database and immunofluorescence staining, respectively. NPT-gels were prepared using hyaluronic acid, screened neoantigen peptides, and dual clinical adjuvants [Poly(I:C) and thymosin α-1]. Then, the efficacy and corresponding antitumor molecular mechanisms of NPT-gels combined with programmed death receptor 1 and cytotoxic T-lymphocyte-associated protein 4 double blockade (PCDB) for the treatment of liver metastases were investigated using various preclinical liver metastasis models.

Results: Liver metastases are associated with poorer 5-year overall survival, characterized by low infiltration of cytotoxic CD8⁺ T cells and high infiltration of regulatory T cells (Tregs). NPT-gels overcame the challenges faced by conventional neoantigen peptide vaccines by sustaining a durable, high-intensity immune response with a single injection and significantly improving the infiltration of neoantigen-specific T-cell subpopulations in different mice subcutaneous tumor models. Importantly, NPT-gels further combined with PCDB could enhance neoantigen-specific T-cell infiltration and effectively unlock the immunosuppressive microenvironment of liver metastases, showing superior antitumor efficacy and inducing long-term immune memory in various preclinical liver metastasis models without obvious toxicity. Mechanistically, the combined strategy can inhibit Tregs, induce the production and infiltration of neoantigen-specific CD8⁺CD69⁺ T cells to enhance the immune response, and potentially elicit antigen-presenting effects in Naïve B_Ighd⁺ cells and M1-type macrophages.

Conclusions: This study demonstrated that NPT-gels combined with PCDB could exert a durable and powerful antitumor immunity by enhancing the recruitment and activation of CD8⁺CD69⁺ T cells, which supports the rationale and clinical translation of this combination strategy and provides important evidence for further improving the immunotherapy efficacy of liver metastases in the future.

Background: Pancreatic ductal adenocarcinoma (PDAC) represents a major clinical challenge due to its tumor microenvironment, which exhibits immune-suppressive properties that facilitate cancer progression, metastasis, and therapy resistance. Interleukin 1 (IL-1) signaling has been implicated as a driver in this process. Mechanistically, both IL-1α and IL-1β bind to the IL-1 receptor type 1, forming a complex with IL-1-receptor accessory protein (IL1RAP), which triggers downstream signaling pathways. The IL1RAP blocking antibody nadunolimab is currently in clinical development, but the precise consequences of inhibiting IL-1 signaling in PDAC remains elusive.

Methods: To evaluate the biological relevance of blocking IL1RAP using nadunolimab in a PDAC animal model, human PDAC cells and cancer-associated fibroblasts (CAFs) were co-transplanted into mice. To study the underlying mechanisms of IL1RAP blockade ex vivo, co-cultured PDAC cells and CAFs were treated with nadunolimab prior to RNA sequencing. Migration assays were performed to assess how nadunolimab affects interactions between CAFs and myeloid immune cells. Finally, to establish a clinical correlation between IL1RAP expression and nadunolimab treatment effects, we analyzed tumor biopsies from a clinical phase I/II study in which nadunolimab was administered to patients.

Results: In the xenograft mouse model, nadunolimab exhibited antitumor effects only when human CAFs were co-transplanted with PDAC cells. IL-1 stimulation induced CAFs to secrete chemokines that recruited neutrophils and monocytes. The secretion of this chemokine and the migration of myeloid cells were inhibited by nadunolimab. Media conditioned by IL-1-stimulated CAFs sustained a neutrophil population with a tissue invasion phenotype, an effect that was reversed by nadunolimab. In a cohort of metastatic late-stage PDAC patients receiving nadunolimab as monotherapy, high IL1RAP expression in tumors was associated with extended progression-free survival.

Conclusions: Our study demonstrates that targeting IL1RAP on CAFs inhibits IL-1-induced chemokine secretion and recruitment of neutrophils and monocytes, thereby counteracting the immunosuppressive microenvironment in PDAC. These findings highlight the therapeutic potential of targeting IL1RAP in PDAC.

Background: Amplification of the programmed cell death-ligand 1 gene (CD274) is highly prevalent and associated with a high response rate to immune checkpoint inhibitors (ICIs) in lymphomas, and is also a potential biomarker for ICI treatment of solid tumors. However, the efficacy of ICIs for solid tumors with CD274 amplification identified by comprehensive genomic profiling (CGP) has been unclear. We here examined ICI efficacy for solid tumors with CD274 amplification identified by CGP in a national database.

Methods: We retrospectively analyzed data from the Center for Cancer Genomics and Advanced Therapeutics database containing 60,155 CGP test results for individuals with solid tumors. Only clinical data from patients treated with ICIs alone (not those undergoing concomitant therapy with molecularly targeted or cytotoxic chemotherapeutic agents) were evaluated. We matched 48 patients in the CD274 amplification-positive group with 170 patients in the CD274 amplification-negative group in a 1:4 ratio based on tumor type, histology, treatment, and age. Overall survival (OS), time to next treatment (TTNT), and response rate were evaluated as treatment outcomes in the two groups.

Results: OS was similar in the CD274-amplified and matched CD274-non-amplified groups (median of 22.1 vs 26.3 months, respectively; HR of 0.92 with a 95% CI of 0.55 to 1.54; p=0.075). TTNT tended to be longer in the CD274-amplified group than in the matched CD274-non-amplified group (median of 16.5 vs 14.0 months; HR of 0.63 with a 95% CI of 0.37 to 1.08; p=0.091). The objective response rate was 33.3% and 18.4% (difference of 14.9%, with a 95% CI of -0.2% to 31.6%), and the disease control rate was 63.9% and 41.1% (difference of 22.8%, with a 95% CI of 5.1% to 40.4%), in the CD274-amplified and matched CD274-non-amplified groups, respectively.

Conclusions: The number of patients with solid tumors positive for CD274 amplification in this analysis is the largest to date, and our results suggest that such gene amplification may be associated with the outcome of ICI treatment in such individuals. CD274 amplification identified by CGP may therefore be a predictor of ICI efficacy for solid tumors.

Trial registration number: UMIN000029779.

Background: Infusion of T cells modified with a chimeric antigen receptor (CAR) targeting CD19 has achieved exceptional responses in patients with non-Hodgkin's lymphoma (NHL), which led to the approval of CAR targeting CD19 (CART19) (Axi-cel and Liso-cel) as second line of treatment for adult patients with relapsed/refractory NHL. Unfortunately, 60% of patients still relapse after CART19 due to either a loss of expression of the target antigen (CD19) in the tumor cell, observed in 27% of relapsed patients, a limited CAR-T persistence, and additional mechanisms, including the suppression of the tumor microenvironment. Clinic strategies to prevent target antigen loss include sequential treatment with CARs directed at CD20 or CD22, which have caused loss of the second antigen, suggesting targeting other antigens less prone to disappear. CD79b, expressed in NHL, is a target in patients treated with antibody-drug conjugates (ADC). However, the limited efficacy of ADC suggests that a CAR therapy targeting CD79b might improve results.

Methods: We designed three new CARs against CD79b termed CAR for Lymphoma (CARLY)1, 2 and 3. We compared their efficacy, phenotype, and inflammatory profiles with CART19 (ARI0001) and CARTBCMA (ARI0002h), which can treat NHL. We also analyzed the target antigen's expression loss (CD79b, CD19, and B-cell maturation antigen(BCMA)).

Results: We found that CARLY2 and CARLY3 had high affinity and specificity towards CD79b on B cells. In vitro, all CAR-T cells had similar anti-NHL efficacy, which was retained in an NHL model of CD19^- relapse. In vivo, CARLY3 showed the highest efficacy. Analysis of the loss of the target antigen demonstrated that CARLY cells induced CD79b and CD19 downregulation on NHL cells with concomitant trogocytosis of these antigens to T cells, being most notorious in CARLY2, which had the highest affinity towards CD79b and CD19, and supporting the selection of CARLY3 to design a new treatment for patients with NHL. Finally, we created a CAR treatment based on dual targeting of CD79b and BCMA to avoid losing the target antigen. This treatment showed the highest efficacy and did not cause loss of the target antigen.

Conclusions: Based on specificity, efficacy, and loss of the target antigen, CARLY3 represents a potential novel CAR treatment for NHL.

Background: Neoantigens are promising immunogens for cancer vaccines and are often delivered as adjuvanted peptide vaccines. Adenoviral (Ad) vectors have been shown to induce strong CD8⁺ T cell responses as vaccines against SARS-CoV-2, Ebola, and Zika, but their utility as neoantigen delivery vectors remains largely unexplored. In this study, we examine how an Ad-vectored neoantigen vaccine would impact tumor immunity compared with a peptide neoantigen vaccine.

Methods: We generated Ad serotype 26 (Ad26) vaccine candidates encoding B16-F10-ovalbumin (OVA) and MC38-specific neoantigens. Ad26 vaccines were compared with adjuvanted peptide delivery as prophylactic vaccines in B16-F10-OVA and MC38 challenge models. Immune responses induced by the best Ad26 vaccine (Ad26.VP22.7Epi) were compared with peptide vaccination systemically and within the tumor. Following vaccination with Ad26.VP22.7Epi, peptide, or sham, tumor-infiltrating CD45⁺ cells were analyzed using single-cell RNA sequencing (scRNA-seq) and T cell receptor sequencing (TCR-seq) to identify vaccine-induced differences in the tumor microenvironment.

Results: Single-shot Ad26 vaccines induced greater neoantigen-specific interferon-γ CD8⁺ T cell immune responses than two-shot adjuvanted peptide vaccines in mice, and Ad26.VP22.7Epi also provided superior protective efficacy compared with the peptide vaccine following tumor challenge. Ad26.VP22.7Epi induced a robust immunodominant CD8⁺ T cell response against the Adpgk neoantigen, while the peptide vaccine-induced lower responses against both Adpgk and Reps1 neoantigens. scRNA-seq analysis of CD45⁺ tumor-infiltrating cells demonstrated that both Ad26.VP22.7Epi and peptide vaccine-induced similar numbers of infiltrating CD8⁺ T cells. However, Ad26.VP22.7Epi induced CD8⁺ T cells showed more upregulation of T cell maturation, activation, and Th1 pathways compared with peptide vaccine induced CD8⁺ T cells, suggesting improved functional T cell quality. TCR-seq of these tumor-infiltrating lymphocytes also demonstrated that Ad26.VP22.7Epi generated larger T cell hyperexpanded clones compared with the peptide vaccine.

Conclusions: These results suggest that the Ad26.VP22.7Epi vaccine led to improved tumor control compared with the peptide vaccine due to increased T cell hyperexpansion and functional activation. Our data suggest that future cancer vaccine development strategies should focus on inducing functional hyperexpanded CD8⁺ T cell responses and not only maximizing tumor infiltrating CD8⁺ T cell numbers.

Background: Loss-of-function mutations of liver kinase B (LKB1, also termed as STK11 (serine/threonine kinase 11)) are frequently detected in patients with non-small cell lung cancer (NSCLC). The LKB1 mutant NSCLC was refractory to almost all the antitumor treatments, including programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) blockade therapy. Unfortunately, mechanisms underlying resistance to immunotherapy are not fully understood. In this study, we deciphered how LKB1 regulated sensitivity to anti-PD-1/PD-L1 immunotherapy.

Methods: We investigated the mutational landscape of LKB1 mutant NSCLC in next generation sequencing (NGS) data sets. Expression of LKB1, PD-L1 and S-phase kinase-associated protein 2 (Skp2) in NSCLC samples were assessed by immunohistochemistry (IHC). The tumor microenvironment (TME) profiling of LKB1 wild type (WT) and mutant NSCLC was performed using fluorescent multiplex IHC. Mass spectrometry and enrichment analysis were used to identify LKB1 interacting proteins. Mechanistic pathways were explored by immunoblotting, ubiquitination assay, cycloheximide chase assay and immunoprecipitation assay.

Results: By using NGS data sets and histological approaches, we demonstrated that LKB1 status was positively associated with PD-L1 protein expression and conferred a T cell-enriched "hot" TME in NSCLC. Patients with good responses to anti-PD-1/PD-L1 immunotherapy possessed a high level of LKB1 and PD-L1. Skp2 emerged as the molecular hub connecting LKB1 and PD-L1, by which Skp2 catalyzed K63-linked polyubiquitination on K136 and K280 residues to stabilize PD-L1 protein. Inhibition of Skp2 expression by short hairpin RNA or its E3 ligase activity by compound #25 abrogated intact expression of PD-L1 in vitro and generated a T cell-excluded "cold" TME in vivo. Thus, the LKB1-Skp2-PD-L1 regulatory loop was crucial for retaining PD-L1 protein expression and manipulation of this pathway would be a feasible approach for TME remodeling.

Conclusion: LKB1 and Skp2 are required for intact PD-L1 protein expression and TME remodeling in NSCLC. Inhibition of Skp2 resulted in a conversion from "hot" TME to "cold" TME and abrogated therapeutic outcomes of immunotherapy. Screening LKB1 and Skp2 status would be helpful to select recipients who may benefit from anti-PD-1/PD-L1 immunotherapy.

Background: Tertiary lymphoid structures (TLS) within the tumor microenvironment have been associated with cancer prognosis and therapeutic response. However, the immunological pattern of a high peritumoral TLS (pTLS) density and its clinical potential in hepatocellular carcinoma (HCC) remain poor. This study aimed to elucidate biological differences related to pTLS density and develop a radiomic classifier for predicting pTLS density in HCC, offering new insights for clinical diagnosis and treatment.

Methods: Spatial transcriptomics (n=4) and RNA sequencing data (n=952) were used to identify critical regulators of pTLS density and evaluate their prognostic significance in HCC. Baseline MRI images from 660 patients with HCC who had undergone surgery treatment between October 2015 and January 2023 were retrospectively recruited for model development and validation. This included training (n=307) and temporal validation (n=76) cohorts from Xiangya Hospital, and external validation cohorts from three independent hospitals (n=277). Radiomic features were extracted from intratumoral and peritumoral regions of interest and analyzed using machine learning algorithms to develop a predictive classifier. The classifier's performance was evaluated using the area under the curve (AUC), with prognostic and predictive value assessed across four independent cohorts and in a dual-center outcome cohort of 41 patients who received immunotherapy.

Results: Patients with HCC and a high pTLS density experienced prolonged median overall survival (p<0.05) and favorable immunotherapy response (p=0.03). Moreover, immune infiltration by mature B cells was observed in the high pTLS density region. Spatial pseudotime analysis and immunohistochemistry staining revealed that expansion of pTLS in HCC was associated with elevated CXCL9 and CXCL10 co-expression. We developed an optimal radiomic-based classifier with excellent discrimination for predicting pTLS density, achieving an AUC of 0.91 (95% CI 0.87, 0.94) in the external validation cohort. This classifier also exhibited promising stratification ability in terms of overall survival (p<0.01), relapse-free survival (p<0.05), and immunotherapy response (p<0.05).

Conclusion: We identified key regulators of pTLS density in patients with HCC and proposed a non-invasive radiomic classifier capable of assisting in stratification for prognosis and treatment.

Background: Immune checkpoint blockade is a promising anticancer therapy, whereas the presence of T cells in tumor sites is indispensable for its therapeutic efficacy. To promote the infiltration of T cells and dendritic cells (DCs) into the tumor, we previously proposed a local cell therapy using chemokine (C-C motif) ligand 19 (CCL19)-expressing immortalized syngeneic immortalized mesenchymal stem cells (syn-iMSC/CCL19). However, the preparation of syngeneic/autologous MSC from individual hosts limits the clinical application of this cell therapy.

Methods: In this study, we further developed a new cell therapy using allogeneic iMSC/CCL19 (allo-iMSC/CCL19) using several tumor mice models.

Results: The allo-iMSC/CCL19 therapy exerted drastic antitumor effects, in which the host's T cells were induced to respond to allogeneic MSC. In addition, the allo-iMSC/CCL19 therapy promoted the infiltration of CD103⁺ interleukin (IL)-12-producing DCs and priming of CD8⁺ T cells at tumor sites compared with that using syn-iMSC/CCL19. The antitumor effect of allo-iMSC/CCL19 therapy was not influenced by fingolimod, a sphingosine 1-phosphate receptor modulator, implying no involvement of draining lymph nodes in the priming of tumor-specific T cells.

Conclusion: These results suggest that allo-iMSC/CCL19 therapy exerts dramatic antitumor effects by promoting the infiltration of CD103⁺ IL-12-producing DCs and thereby priming tumor-specific CD8⁺ T cells at tumor sites. This local cell therapy could be a promising approach to anticancer therapy, particularly for overcoming dysfunction in the cancer-immunity cycle.

Objective: Although immune checkpoint blockade (ICB) therapy represents a bright spot in antitumor immunotherapy, its clinical benefits in colorectal cancer (CRC) are limited. Therefore, a new target for mediating CRC immunosuppression is urgently needed. Adenomatous polyposis coli (APC) mutations have been reported as early-stage characteristic events in CRC, but the role of truncated APC in the CRC immune microenvironment remains unclear and its clinical significance has yet to be explored.

Design: Adenocarcinoma formation in the colon of the APC^Min/+ mouse model, which displays features associated with the translation of truncated APC proteins, was induced by azoxymethane/dextran sodium sulfate. Multiplexed immunohistochemical consecutive staining on single slides and flow cytometry were used to explore the activation of immune cells and the expression of the immune checkpoint V-domain immunoglobulin suppressor of T-cell activation (VISTA) in the CRC tissues of APC^WT and APC^Min/+ mice. The construction of truncated APC vectors and an initial subserosal graft tumor mouse model was employed to mimic the tumor microenvironment (TME) during APC mutation. Methylated RNA immunoprecipitation-quantitative PCR assays were performed to investigate the N6-methyladenosine (m6A)-dependent transcriptional regulation of hypoxia-inducible factor-1 alpha (HIF1α) by methyltransferase-like protein 3 (METTL3). Mettl3^fl/fl vil1-cre^+/- mice were used to demonstrate that targeting METTL3 is a mediator that mitigates the deleterious effects of the APC978∆-HIF1α axis on antitumor immunity. A chimeric VISTA humanized mouse model was used to evaluate the drug efficacy of the VISTA-targeted compound onvatilimab.

Results: We showed that APC978∆, a truncated APC protein, mediated overexpression of METTL3, resulting in m6A methylation of HIF1α messenger RNA and high expression of HIF1α. Furthermore, HIF1α promotes the migration of myeloid-derived suppressor cells to the TME by binding to the promoters of MCP-1 and MIF. In addition, HIF1α enhances the expression of the immune checkpoint VISTA on CRC cells, weakening tumor immune monitoring.

Conclusions: We elucidate that an underappreciated function of truncated APC in CRC is its ability to drive an immunosuppressive program that boosts tumor progression. Our work could provide a new perspective for the clinical application of immunotherapy in patients with CRC resistant to ICB therapy.

Background: Chimeric antigen receptor (CAR) T cells have demonstrated remarkable breakthroughs in treating hematologic malignancies, yet their efficacy in solid tumors is limited by the immunosuppressive microenvironment. Sympathetic nerves significantly contribute to this immunosuppressive milieu in solid tumors. However, the impact of tumor sympathetic denervation on enhancing CAR T-cell antitumor efficacy remains unclear.

Methods: We screened for sympathetic gene sets in various types of cancers and investigated the association of sympathetic nerves with immunosuppression in renal clear cell carcinoma. Using antibodies to block the nerve growth factor (NGF) pathway, we explored sympathetic nerve distribution in tumor tissues and tumor progression. Additionally, we engineered CAR T cells to secrete NGF single chain fragment variable (scFv) to achieve tumor immunosympathectomy and assessed their antitumor efficacy. Bulk RNA sequencing and single-cell RNA sequencing analyses were conducted to evaluate changes in immune cell phenotypes within the tumor microenvironment.

Results: Blocking the NGF pathway with antibodies effectively reduced sympathetic nerve distribution in tumor tissues and delayed tumor progression. CAR T cells engineered to secrete NGF scFv achieved a similar tumor immunosympathectomy and exhibited enhanced tumor suppression. RNA sequencing analyses revealed that this augmented effect was primarily due to the inhibition of the terminal exhaustion phenotype in tumor-infiltrating CD8 T cells and the prevention of macrophage polarization from M1 to M2. This approach maintained a stronger antitumor immune state at the tumor site. Additionally, splenic T cells also exhibited a more potent immune effector phenotype following the infusion of NGF scFv-secreting CAR T cells.

Conclusions: Our results suggest that immunosympathectomy is a novel approach to weaken tumor microenvironment immunosuppression and synergistically enhance CAR T-cell efficacy against solid tumors.