Journal for Immunotherapy of Cancer最新文献

Background: To date, a growing body of evidence suggests that unfolded protein response (UPR) sensors play a vital role in carcinogenesis. However, it remains unclear whether they are involved in pancreatic ductal adenocarcinoma (PDAC) and how they relate to clinical outcomes. This study aims to investigate the biological function and mechanism of how a novel UPR sensor, CREB3L1 works in PDAC and further evaluate its clinical application prospect.

Methods: We tested UPR signaling including CREB3L1 in Thapsigargin-treated PDAC cells. Subsequently, we defined CREB3L1 expression and further analyzed its expression with clinical characteristics in PDAC. Then, we established gene-modified cells to determine whether CREB3L1 functions in cell proliferation and migration capacity. Besides, we constructed subcutaneously and orthotopically transplanted mice models to verify their progrowing function and pulmonary metastasis models to prove their proinvasion role. What's more, RNAseq, qPCR, Western blotting, immunohistochemistry and multicolor flow cytometry experiments were used to explore the mechanism of how CREB3L1 worked in PDAC. Lastly, CREB3L1 expression correlation with PDAC immunotherapy outcome and immune cell signatures were explored in the patients with advanced PDAC who received PD-1 antibody therapy.

Results: We first confirmed CREB3L1 could be induced by endoplasmic reticulum stressor and found its aberrant activation was associated with poorer overall survival in PDAC patients indicating the protumor function of the new UPR sensor. Functionally, we confirmed CREB3L1 contributing to PDAC malignant progression including growth and metastasis by multiple in in vitro and in vivo models. Mechanistically, CREB3L1 upregulated COL3A1 and promoted dense stroma formation for facilitating PDAC and knocking down COL3A1 disrupted CREB3L1 protumor function. Furthermore, CREB3L1-induced TAM polarization toward an M2 phenotype and reduced the infiltration of CD8⁺ T cells. Clinically, CREB3L1 correlated with immune cell signatures as well as immune checkpoint blockade (ICB) treatment response and outcome that CREB3L1aberrant activation indicated poorer efficacy and worse prognosis than the low in PDAC which might empower clinical decision.

Conclusions: Collectively, this study revealed CREB3L1 facilitated PDAC progression, shaped an immune exclude tumor microenvironment and distinguished therapy response and outcome of ICB therapy indicating CREB3L1 could be a promising novel molecular target and biomarker for PDAC treatment.

Background: Therapeutic efficacy of carcinoembryonic antigen (CEA)-specific chimeric antigen receptor (CAR) T cells against colorectal cancer (CRC) remains limited due to the unique characteristics and distinct microenvironments of tumor tissues. We modified CEA-specific CAR-T cells, aiming to stimulate endogenous CD8⁺ T cell responses against neoantigens that were derived from CEA-positive tumors destroyed by the CAR T cells.

Methods: In a conventional CEA CAR (reg-CAR), we modified it to express lymphotactin XCL1 and interleukin (IL)-7 genes, constructing a modified 7XCL1-CAR. By generating the CEA-specific 7XCL1-CAR T cells, we assessed their antitumor efficacy against CRC cells with varying levels of CEA expression, both in cell-cultures and in two strains of tumor-bearing syngeneic mice.

Results: Following retroviral transduction, 7XCL1-CAR T cells and reg-CAR T cells exhibited similar positive proportions of CEA-CAR and CD4:CD8 ratios. In co-culture system with CEA-negative CT26 cells, no differences in cytotoxicity were observed between 7XCL1-CAR and reg-CAR T cells. However, in co-culture with CT26.CEA^high and CT26.CEA^int cells, 7XCL1-CAR T cells displayed higher cytotoxicity than that reg-CAR T cells after 60 hours. On interaction with CT26.CEA-positive cells, 7XCL1-CAR T cells secreted higher levels of XCL1 and IL-7, effectively recruited the most potent cross-presenting cDC1s (type-I conventional dendritic cells), and sustained the antitumor activity of CAR-T cells. In treating mice that carried tumors derived from universally CEA-positive cells, 7XCL1-CAR T cells exhibited no difference compared with reg-CAR T cells. However, in treating mice with tumors containing both CEA-positive and CEA-negative cells, 7XCL1-CAR T cells displayed greater inhibition than that of reg-CAR-T cells. After treatment of 7XCL1-CAR T cells, tumor-bearing mice exhibited enhanced infiltration of cDC1s, maintained CAR-T activity, and generation of endogenous neoantigen-specific T cells. Consequently, 7XCL1-CAR T cell-treated mice demonstrated resistance to challenge with CEA-negative CT26 cells.

Conclusion: Treatment with CEA-specific, XCL1-secreting CAR-T cells for CEA-positive tumors promoted the generation of CD8⁺ T cells against tumor neoantigens, mediating a long-term antitumor immunity against heterogeneous CRCs.

Background: Tumor cells can drive the senescence of effector T cells by unbalancing their lipid metabolism, thereby limiting adoptive T cell therapy and contributing to tumor immune evasion. Our objective is to provide a feasible strategy for enhancing T cell treatment efficacy against solid tumors.

Methods: In this study, liposomal arachidonyl trifluoromethyl ketone (ATK) was anchored onto the adoptive T cell surface via bioorthogonal reactions, aiming to specifically inhibit the group IVA cytosolic phospholipase A₂α (cPLA₂α), a key enzyme facilitating phospholipid metabolism and senescent state of T cells.

Results: The surface engineering exerted rare side effects on the activation and migration of T cells, but local and sustained extravasation of ATK downregulated cPLA2α expression, reprogrammed lipid metabolism, and inhibited lipid droplet accumulation. This endows T cells with delayed senescence and declined apoptosis to maintain their tumor-killing potency. Systemic administration of surface-engineered T cells resulted in superior infiltration in solid tumors and improved antitumor efficacy by enhancing the secretion of cytotoxic molecules, thereby prolonging the survival of mice bearing colorectal carcinoma and melanoma xenografts.

Conclusions: Lipid-metabolically remodeled T cells with delayed senescence increase efficacy in tumor microenvironment, highlighting a novel strategy for solid tumor immunotherapy.

Background: Nivolumab is an immune checkpoint inhibitor (ICI) that selectively inhibits programmed cell death protein 1 activation, restoring antitumor immunity. ICIs are indicated for various types of advanced solid tumors; however, not all patients benefit from them, and tools that could be used in the clinic to predict response to treatment represent an unmet need. Here we describe the development of a new population pharmacokinetic (PPK) model in patients treated with nivolumab in clinical trials. Applying the model to a patient population with renal cell carcinoma identified nivolumab clearance and plasma concentration as predictors of overall survival (OS).

Methods: A custom liquid chromatography with tandem mass spectrometry method for quantifying nivolumab plasma concentration was developed and validated following the European Medicines Agency guidelines for bioanalytical method validation. The PPK model was developed using data from patients treated in the NIVIPIT (n=38) and NIVOREN (n=137) trials of nivolumab in metastatic melanoma and renal cell carcinoma, respectively. The PPK model was used to determine pharmacokinetic (PK) parameters such as baseline clearance and simulate individual clearance changes over time. The relationship between PK characteristics (including clearance at Cycle 1 (CLC1), plasma concentration at Cycle 3 and clinical outcomes was assessed in 137 patients treated in NIVOREN. Kaplan-Meier methodology was used in time-to-event analyses.

Results: In 137 patients, the median nivolumab CLC1 was 6 mL/hour and the median plasma concentration at Cycle 3 was 48 µg/mL. Median follow-up was 21.0 months (95% CI 20.2 to 22.5 months) with a survival rate at 6 months of 91.2% and 77.9% at 12 months. In univariate analysis, OS was significantly higher in patients with CLC1<6 mL/hour versus ≥6 mL/hour (HR 2.2 (95% CI 1.2 to 4.1), p=0.0146). Shorter OS was observed in patients with plasma concentration at Cycle 3 below the median (48 µg/mL) versus those above the median (HR 0.4 (95% CI 0.2 to 0.8), p=0.0069). Multivariate analysis showed a trend towards lower clearance, but this did not reach statistical significance (p=0.0694).

Conclusions: Results of the study may potentially be used to predict outcomes of nivolumab therapy in patients with renal cell carcinoma. Additional applications may include guiding dose adjustments of nivolumab in those who are less likely to respond to the initial dose.

Background: Sialic acid-binding immunoglobulin-like lectins (SIGLECs) are widely expressed on immune cell surfaces, play an important role in maintaining immune homeostasis and regulating inflammatory responses, and are increasingly emerging as potential targets for tumor immunotherapy. However, the expression profile and crucial role of SIGLEC11 in gastric cancer (GC) remain unclear. This study aimed to elucidate the prognostic relevance of SIGLEC11 expression and its role in the immune microenvironment in patients with GC.

Methods: SIGLEC11 expression profile was analyzed using bioinformatics, immunohistochemistry, and immunofluorescence staining. Flow cytometry, mouse tumor models, patient-derived tumor organoid models, and RNA sequencing were used to explore the potential functions with the underlying mechanisms of SIGLEC11 in a coculture system of macrophages and GC cells.

Results: We demonstrated that SIGLEC11 was predominantly expressed in normal tissues. However, tumor-infiltrating SIGLEC11⁺ cells in the high SIGLEC11 expression subgroups showed poor overall survival, which was associated with the expression of an immunosuppressive regulator. Our results showed that SIGLEC11 was predominantly expressed in monocytes and macrophages and selectively upregulated in tumor-associated macrophages. Furthermore, SIGLEC11 promoted macrophage M2 polarization via AKT-mTOR signaling. In addition, SIGLEC11⁺ macrophages accelerate GC progression.

Conclusions: The abundance of SIGLEC11⁺ M2-like macrophage-infiltrating tumors may serve as a biomarker for identifying immunosuppressive subtypes of GC. Thus, the potential role of SIGLEC11⁺ M2 macrophages as therapeutic targets warrants further investigation.

Background: Immune checkpoint inhibitors (ICIs) are recommended to treat patients with deficient mismatch repair/microsatellite instability high (dMMR/MSI-H) metastatic colorectal cancer (mCRC). Pivotal trials have fixed a maximum ICI duration of 2 years, without a compelling rationale. A shorter treatment duration has the potential to improve patients' quality of life and reduce both toxicity and cost without compromising efficacy. Here we examine whether early treatment discontinuation (ETD) before 13 months in patients without progressive disease (PD) can lead to similar long-term disease control compared with a longer treatment duration (LTD).

Methods: To assess whether ETD is associated with similar outcomes compared with LTD, we assembled an international cohort of patients with dMMR/MSI-H mCRC treated with ICIs who stopped treatment for a reason other than PD within 395 days (ETD group) and compared them to those who continued for >395 days (LTD group). Outcomes were adjusted for patient/tumor characteristics. Primary endpoint was progression-free survival (PFS) and secondary endpoints were objective response rate (ORR), overall survival (OS) and safety.

Results: Of 976 patients, 137 and 394 were allocated to the ETD and LTD groups, respectively. In the ETD group, treatment was discontinued due to toxicity (n=56), objective response (n=43), surgery (n=28), patient decision (n=2) or other reasons (n=8). Baseline characteristics were well balanced between the two groups: 22% in both groups received both anti-programmed death-(ligand) 1 (anti-PD-(L)1) + anti-cytotoxic T-lymphocyte antigen-4 (anti-CTLA-4); all others received anti-PD-(L)1 monotherapy. ORR to ICIs was 81% in both groups. Median duration of treatment was ~7 months in the ETD and ~24 months in the LTD group. After a median follow-up of 44 months (IQR: 30-67), similar PFS (HR: 0.92, 95% CI: 0.60 to 1.40, p=0.69) and OS (HR: 1.15, 95% CI: 0.66 to 1.99, p=0.62) from the start of ICIs were observed in ETD and LTD patients. In the ETD group, 28 (20%) patients had a PFS event and 9 restarted ICIs with a disease control rate of 66%.

Conclusions: In our international series of dMMR/MSI-H mCRC, ETD of ICIs in the absence of PD did not seem detrimental in terms of PFS and OS compared with continuing treatment beyond 1 year. Randomized clinical trials to compare short and long treatment duration are now warranted.

Background: Immune checkpoint inhibitors (ICIs) in combination with antiangiogenic drugs have shown promising outcomes in the third-line and subsequent treatments of patients with microsatellite stable metastatic colorectal cancer (MSS-mCRC). Radiotherapy (RT) may enhance the antitumor effect of immunotherapy. However, the effect of RT exposure on patients receiving ICIs and targeted therapy remains unclear. This study aimed to investigate the association between RT exposure and clinical responses to fruquintinib (a highly selective tyrosine kinase inhibitor of vascular endothelial growth factor receptor) plus sintilimab (an anti-programmed death 1 antibody; F&S) in previously treated patients with MSS-mCRC and to explore predictive biomarkers.

Methods: In this prospective observational study, patients with mCRC receiving F&S as third-line or subsequent treatment were enrolled. Eligible patients were divided into the RT cohort (RTC) and the non-RT cohort (NRTC) according to their RT history. The primary endpoint was the objective response rate (ORR). Secondary endpoints included disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety. Pretreatment fecal and serum samples were collected for microbiome analysis, metabolome analysis, and immune signatures to identify biomarkers for treatment.

Results: A total of 55 patients were included, of which 25 were in the RTC and 30 in the NRTC. Better ORR (28.0% vs 6.7%, p=0.048), DCR (80.0% vs 36.7%, p=0.002), median PFS (6.2 vs 2.7 months, p<0.001), and median OS (14.8 vs 5.9 months, p=0.019) were noted in patients with RTC than those with NRTC. The enrichment of Lactobacillus, Bifidobacterium, and PC(20:5(5Z,8Z,11Z,14Z,17Z)/20:3(8Z,11Z,14Z)) in RTC significantly predicted better DCR and PFS, whereas guanosine and interleukin-10 predominated in patients with NRTC were negatively correlated with PFS and OS.

Conclusions: Patients with RT exposure benefited significantly from F&S in the third-line or subsequent treatment for MSS-mCRC. Gut microbiota, metabolites, and cytokines may help predict F&S outcomes for mCRC, which may be helpful in treatment decision-making.

Trial registration number: ClinicalTrials.gov identifier: NCT05635149.

Background: Cancer immunotherapy using immune checkpoint blockade (ICB) has revolutionized cancer treatment. However, patients with multiple myeloma (MM) rarely respond to ICB. Accumulating evidence indicates that the complicated tumor microenvironment (TME) significantly impacts the efficacy of ICB therapy. Therefore, investigating how TME components in MM influence ICB treatment is urgent.

Methods: We employed two well-established murine myeloma models, 5TGM1 and Vk*MYC, by intravenously injecting 5TGM1 or Vk*MYC cells into mice, respectively, to determine ICB therapeutic efficacy in MM. Total mouse IgG or Ig2b ELISA or QuickGel split beta SPE kits and in vivo bioluminescent imaging were used to monitor MM tumor burden. Cytometry by time of flight (CyTOF) was used to quantify MM TME components. T cell proliferation and function were detected using flow cytometry. Peptide-Fc fusion proteins were used to deplete myeloid-derived suppressor cells (MDSCs). MM^DTR, Foxp3^DTR, CD4 KO and CD8 KO mice were used to elucidate the underlying mechanisms. Gene expression levels in human MM were analyzed using Gene Expression Omnibus public datasets.

Results: We found that programmed cell death protein 1 (PD-1) antibody treatment had a therapeutic effect in 5TGM1 mice; it was ineffective in Vk*MYC mice. CyTOF indicated that the bone marrow (BM) of both models was inflamed, suggesting that immune suppressive cells might be inhibiting the reactivation of T cells in the BM. We observed higher numbers of MDSCs, regulatory T (Treg) cells, and tumor-associated macrophage (TAMs) in myeloma BM compared with that of tumor-free mice. Specifically, depleting MDSCs, but not Treg cells or TAMs, sensitized Vk*MYC mice and enhanced the response of 5TGM1 mice to PD-1 ICB, which was dependent on CD8⁺ but not CD4⁺ T cells. MDSCs, especially M-MDSCs and CD84⁺ MDSCs, significantly inhibited the activation and cytotoxic cytokine production of CD8⁺ T cells in vitro. Moreover, database profiling of patient BM revealed a negative correlation between MDSCs signature genes and cytotoxic CD8⁺ T cell signature genes, with post-maintenance patients with myeloma displaying a higher ratio of cytotoxic CD8⁺ T cell to MDSCs signature genes compared with pretreated patients.

Conclusion: Our study highlights the potential of MDSCs depletion in enhancing the sensitivity of patients with myeloma to PD-1 ICB therapy.

Background: Siglec-E is an immune checkpoint inhibitory molecule. Expression of Siglec-E on the immune cells has been shown to promote tumor regression. This study aimed to develop an adenovirus (Ad) vaccine targeting Siglec-E and carbonic anhydrase IX (CAIX) (Ad-Siglec-E/CAIX) and to evaluate its potential antitumor effects in several preclinical renal cancer models.

Methods: Ad vaccines encoding Siglec-E or CAIX were developed and evaluated for their therapeutic potential in mouse subcutaneous, lung metastatic, and orthotopic tumor models. The expression of Ad-Siglec-E/CAIX was confirmed via PCR and flow cytometry. Immune responses induced by Ad-Siglec-E/CAIX were assessed in vitro and in vivo using flow cytometry, immunohistochemistry, ELISA, histological analysis, cell proliferation, enzyme-linked immunosorbent spot, cytotoxic T lymphocytes (CTL) killing, and cell depletion assays.

Results: Ad-Siglec-E/CAIX vaccine induced the increase of tumor-infiltrated immune cells, and significantly suppressed the subcutaneous tumor growth of renal carcinoma. Immunization with Ad-Siglec-E/CAIX promoted the induction and maturation of CD11c⁺ dendritic cells and their subsets, which in turn enhanced tumor-specific CD8⁺ T cell immune responses, as evidenced by increased CD8⁺ T cell proliferation and CTL activity. Importantly, the deletion of CD8⁺ T cells in vivo abolished the antitumor effect of the Ad-Siglec-E/CAIX vaccine, highlighting the essential role of functional CD8⁺ T cell responses. The potent therapeutic efficacy of the Ad-Siglec-E/CAIX vaccine was also observed in lung metastasis and orthotopic tumor models through tumor-specific CD8⁺ T cell immune responses.

Conclusions: Our results indicate that targeting Siglec-E enhances the therapeutic efficacy of Ad-CAIX against renal carcinoma, providing a promising therapeutic option for solid tumors.