Journal for Immunotherapy of Cancer最新文献

Background: Patients with metastatic pancreatic ductal adenocarcinoma (mPDAC) often respond to cytotoxic therapy, but early disease progression is typical. Responses to immunotherapy alone are rare. Recent advances in chemoimmunotherapy combinations offer promise. We report results from cohorts A and B of REVOLUTION, an adaptive platform trial designed to evaluate the safety and antitumor activity of chemoimmunotherapy combinations in untreated mPDAC.

Methods: REVOLUTION (NCT04787991) is an open-label, exploratory platform trial. Patients were assigned to enrolling cohorts in a non-randomized fashion. All patients received gemcitabine (1,000 mg/m²), nab-paclitaxel (125 mg/m²), and two doses of ipilimumab (1 mg/kg), administered intravenously. In addition, cohort A received nivolumab (360 mg intravenously every 3 weeks) and cohort B received hydroxychloroquine (600 mg orally two times a day). The primary endpoint was safety. Secondary endpoints included objective response rate (ORR), disease control rate, duration of response, progression-free survival, and overall survival (OS). Exploratory endpoints included pharmacodynamic changes and associations between biomarkers and clinical outcomes.

Results: Both cohorts enrolled 15 patients. Grade 3-4 treatment-related adverse events occurred in 60% and 53% of patients in cohorts A and B, respectively. One grade 5 event occurred in cohort B, which exhibited more frequent dose modifications and non-compliance. Cohort A demonstrated an ORR of 33% (5/15) and a 12-month OS rate of 65.5% (95% CI 35.7% to 84.0%), with higher baseline levels of programmed cell death protein-1 (PD-1)⁺CD39⁺ central memory CD4⁺ T cells associated with prolonged survival. Cohort B demonstrated an ORR of 40% (6/15) and a 12-month OS rate of 53.9% (95% CI 24.3% to 76.3%). Cohort A showed increases in activated and proliferating CD4⁺ and CD8⁺ T cells, regulatory T cells, and circulating soluble PD-1 and Th1-associated cytokines. Cohort B exhibited delayed but sustained increases in activated CD4⁺ T cells and pharmacodynamic evidence of autophagy inhibition.

Conclusions: REVOLUTION cohorts A and B demonstrated encouraging antitumor activity in patients with mPDAC. In cohort B, hydroxychloroquine-related tolerability issues contributed to early discontinuations and reduced drug exposure. These findings highlight the potential and limitations of current chemoimmunotherapy approaches. Although neither cohort will be expanded, the results reinforce the continued promise of chemoimmunotherapy in mPDAC and the importance of refining these strategies.

Background: Neoadjuvant PD-1/PD-L1 blockade yields robust efficacy in advanced cutaneous squamous cell carcinoma (cSCC), yet many patients fail to achieve a complete or major pathologic response. The reasons why some patients experience response but others do not are unclear.

Methods: We profiled cSCC specimens before, after 1 dose, and after 3-4 doses of PD-1/PD-L1 blockade to uncover resistance mechanisms and predict therapeutic response. In total, 27 patients across three cohorts, including two phase II trials, were studied. We created 1.7 mm tissue-core microarrays and performed single-cell spatial transcriptomics, including spatial clustering, gene-set enrichment, and spatial correlation analyses.

Results: After profiling all samples, six distinct spatial niches emerged, each differentially enriched in responders versus non-responders. A high antigen presentation niche, B/plasma cell enriched niche, and inflammatory keratinocyte niche were more frequent in responders, whereas proliferative keratinocyte, low antigen presentation myeloid, and fibroblast-rich epithelial-mesenchymal transition niches prevailed in non-responders. Notably, spatial niche profiling on pretreatment samples outperformed PD-L1 status in predicting pathologic response. Each niche displayed unique gene coexpression modules, suggesting niche-specific resistance mechanisms. Individual tumor analyses revealed varied immune evasion strategies, including defective interferon-induced antigen presentation, immunosuppressive myeloid environments, and epithelial-mesenchymal transition.

Conclusions: Our single-cell spatial transcriptomic approach identifies six spatial niches that predict immunotherapy response better than PD-L1 status using only 1.7 mm tissue cores and may inform the development of biomarkers. Our results further underscore the heterogeneity of resistance mechanisms among cSCC patients, highlighting the need for tailored therapeutic strategies.

Background: Although immunotherapy has revolutionized cancer treatment, its efficacy in castration-resistant prostate cancer (CRPC) remains limited, largely due to an immunologically "cold" tumor microenvironment with scarce T-cell infiltration. Unraveling the molecular mechanisms underlying immune evasion and developing novel strategies to activate innate antitumor immunity are therefore critical to overcoming immunotherapy resistance in CRPC.

Methods: Using bioinformatic approaches, we analyzed the protein kinase membrane-associated tyrosine/threonine 1 (PKMYT1) expression and its correlation with immune cell infiltration and response to immune checkpoint blockade (ICB) in public databases. PKMYT1 protein expression was further evaluated via immunohistochemistry in a clinical cohort of prostate cancer (PCa) specimens. Mechanistic investigations were conducted in PCa cell lines and mouse models. The immunological impact of PKMYT1 inhibition was delineated using single-cell RNA sequencing, and the therapeutic efficacy of RP-6306, either as monotherapy or in combination with programmed death-ligand 1 (PD-L1) blockade, was evaluated in syngeneic mouse models.

Results: PKMYT1 expression was significantly overexpressed in CRPC compared with primary PCa. High PKMYT1 expression correlated with a suppressed antitumor immunity and poor clinical response to ICB. Mechanistically, PKMYT1 inhibition activated the cyclic guanosine monophosphate-adenosine monophosphate adenosine synthase (cGAS)-stimulator of interferon genes (STING) pathway, potentiated both type I and II interferon signaling, and upregulated chemokines, including CCL5 and CXCL10. The selective PKMYT1 inhibitor, RP-6306, enhanced the efficacy of ICB in the presence of CD8⁺ T cells. Treatment with a PKMYT1 inhibitor alone or in combination with PD-L1 blockade significantly increased the infiltration of activated CD8⁺ T cells and induced significant tumor suppression in vivo.

Conclusion: PKMYT1 is a pivotal dual regulator of tumor progression and immune evasion in CRPC. Our findings provide a compelling preclinical rationale for targeting PKMYT1 as a novel strategy to reprogram the tumor immune microenvironment and overcome resistance to immunotherapy.

Background: Immune checkpoint inhibitor (ICI)-based regimens can be associated with prolonged survival and disease control after treatment discontinuation without further anticancer therapy. An integrated, comprehensive partitioned survival analysis describes how patients spend overall survival (OS) time both on/off treatment and with/without toxicity. Previous analysis of first-line (1L) nivolumab+ipilimumab for advanced renal cell carcinoma (aRCC) in CheckMate 214 showed treatment-free survival (TFS; time between 1L and second-line (2L) therapies) was twice as long versus sunitinib. TFS and survival states for ICI plus vascular endothelial growth factor receptor-tyrosine kinase inhibitor are of interest.

Methods: In CheckMate 9ER, 651 randomized patients with aRCC received 1L nivolumab+cabozantinib or sunitinib. Minimum follow-up was 4 years. We partitioned area under the Kaplan-Meier OS curve into three survival states defined from randomization: time on 1L protocol therapy, TFS, and survival after 2L subsequent systemic therapy initiation. TFS and protocol therapy were subdivided into mean times with/without grade 2+ treatment-related adverse events. Areas under and between Kaplan-Meier curves were estimated by 48-month restricted mean times to event. Bootstrapped 95% CIs for between-group differences are reported.

Results: At 4 years post-randomization, Kaplan-Meier OS estimates were 49.2% versus 40.2% with nivolumab+cabozantinib and sunitinib, respectively; 17.6% versus 4.7% of patients were in TFS; 15.8% versus 8.2% remained on 1L protocol therapy. The 48-month mean time on protocol therapy for nivolumab+cabozantinib versus sunitinib was 22.6 and 14.1 months; 48-month mean TFS was 7.0 and 4.6 months (difference, 2.4 (95% CI 0.8 to 3.9)); 48-month mean survival after 2L therapy initiation was 5.5 and 12.0 months, respectively. The nivolumab+cabozantinib group spent 8.5 (95% CI 6.2 to 10.8) months more mean survival time on 1L protocol therapy, whereas the sunitinib group had 6.5 (95% CI 4.4 to 8.6) months more mean survival time after 2L therapy initiation. Both treatment groups spent at least half of TFS with grade 2+toxicity, resulting in a difference in mean TFS without toxicity of 0.7 (95% CI -0.4 to 1.8) months.

Conclusions: Partitioned survival analysis over 4 years after initiation of 1L therapy for aRCC indicated that longer OS with nivolumab+cabozantinib versus sunitinib involved more time on 1L therapy and in TFS, and less survival time after 2L therapy initiation.

Trial registration number: NCT03141177.

The inducible T-cell co-stimulator (ICOS, CD278) represents an appealing yet complex target within the CD28 immunoglobulin receptor superfamily. Unlike constitutively expressed co-stimulatory molecules, ICOS is minimally present on naïve T cells and is upregulated following T-cell receptor engagement. This inducible expression pattern, and its crosstalk with other co-stimulatory pathways such as OX40, 4-1BB, CD40, and CD28, position ICOS as a promising candidate for immune agonism. The phase I INDUCE-1 study of the ICOS agonist feladilimab (GSK3359609) employed a pharmacodynamically guided design that prioritized biological activity over toxicity thresholds. Although feladilimab demonstrated favorable safety and robust receptor occupancy, clinical responses were limited-echoing similar experiences with vopratelimab (JTX-2011) and other ICOS agonists. These outcomes highlight that effective ICOS modulation depends not only on receptor engagement but also on spatial and temporal regulation of effector versus regulatory T-cell responses. Future ICOS-directed strategies, whether agonistic or antagonistic, monoclonal or bispecific, will require rational combination approaches and biomarker-driven patient selection to fully harness this pathway's therapeutic potential.

Background: Myeloid-derived suppressor cells (MDSCs) have a dominating presence in the postoperative period, mediating the suppression of natural killer (NK) cells and promoting cancer metastases after surgery. However, their phenotype and effects on postoperative cellular immunity remain incompletely understood. This study aims to functionally characterize surgery-induced (sx) MDSCs and identify potential therapeutic strategies to mitigate their immunosuppressive effects.

Methods: We used multicolor flow cytometry to characterize sx-MDSCs from n=55 patients with cancer undergoing surgery at various time points. Furthermore, single-cell RNA sequencing was performed on a cohort of patients. Our functional ex vivo sx-MDSC:NK cell suppression assay was used to investigate the activity of sx-MDSCs and to screen a 147 small molecule library to identify sx-MDSC antagonists. Lastly, we used preclinical murine models of postoperative metastases to evaluate the therapeutic potential of the inhibitors identified.

Results: Sx-MDSCs significantly expanded after surgery and single-cell RNA sequencing identified signatures resembling immunosuppressive monocytes, including an upregulation of PI3K signaling. These sx-MDSCs also suppressed NK cell activity from patient samples and the small molecule screen identified PI3K-γ inhibitors as potent modulators of sx-MDSC activity. In our murine models, inhibiting PI3K-γ with specific inhibitors reduced postoperative metastases, further corroborating the role of this pathway in sx-MDSC-mediated immune suppression.

Conclusions: Our findings highlight the critical role of PI3K-γ signaling in postoperative sx-MDSC-mediated immune suppression. Targeting this pathway with PI3K-γ inhibitors represents a promising therapeutic strategy to prevent NK cell suppression and reduce postoperative metastases.

Background: Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and the leading cause of cancer-related deaths. Immune checkpoint inhibitors (ICIs) of programmed death-1 (PD-1)/programmed death ligand-1 signaling induce tumor regression in some patients with NSCLC, but most patients with NSCLC exhibit resistance to ICIs therapy. NSCLC shapes the potent tumor immunosuppressive microenvironment (TIME) that underlies tumor immune tolerance and acquired resistance. Therefore, elucidating the cellular and molecular mechanisms by which NSCLC establishes and sustains the TIME is essential for developing novel strategies to overcome immune resistance and enhance the clinical benefit of ICIs.

Methods: The correlation between sterile alpha motif domain and histidine-aspartate domain-containing protein 1 (SAMHD1) expression and ICIs was analyzed via immunohistochemistry. Cell migration assay was performed to assess the effect of SAMHD1 on macrophage recruitment. Multicolor flow cytometry was performed to analyze the effect of SAMHD1 knockdown on the tumor microenvironment. SAMHD1 regulation of the dual specificity phosphatase 6-extracellular regulated protein kinases 1/2 (DUSP6-ERK1/2) pathway was verified by RNA sequencing and western blotting.

Results: Here, we identify the SAMHD1 as a potential therapeutic target and a major determinant of poor response to ICIs in patients with NSCLC. Tumors with high SAMHD1 expression show resistance to anti-PD-1 antibody (αPD-1) treatment, whereas tumors with low SAMHD1 expression are highly sensitive. SAMHD1-dependent resistance to αPD-1 is characterized by increased tumor-associated macrophages (TAMs) infiltration and reduced CD8+T cell numbers. Mechanistically, SAMHD1 regulates the expression of macrophage-associated chemokines by influencing the activation of the DUSP6-ERK1/2 pathway, which contributes to TAMs aggregation within NSCLC tumors to shape an immunosuppressive microenvironment. The HIV accessory protein viral protein-x (VPX) specifically degrades SAMHD1 to promote HIV replication. Similarly, the vpx-engineered oncolytic adenovirus (oAd-vpx) targets SAMDH1 degradation to enhance oncolytic adenovirus replication and weaken the hostile immune microenvironment shaped by TAMs, thereby triggering a CD8+T-cell-dependent antitumor immune response. The combination of oAd-vpx and αPD-1 inhibits tumor growth and enhances sensitivity to ICIs in both mouse and human NSCLC.

Conclusions: This research identifies a key mechanism of SAMHD1-driven immunosuppression and highlights its important role in oncolytic adenovirus therapy. This study provides a theoretical basis for targeting SAMHD1 as a drug therapy strategy in patients with NSCLC.

Background: Chimeric antigen receptor (CAR) T cell therapy has shown remarkable success in hematologic malignancies but faces substantial challenges in solid tumors. One of the main obstacles is the extracellular matrix (ECM), which serves as the physical barrier that hinders T cell infiltration into tumor tissues.

Methods: We engineered CAR-T cells targeting mesothelin or B7H3 to co-express matrix metalloproteinase-3 (MMP3). We evaluated the effects of MMP3 overexpression on CAR-T cell proliferation, activation, cytotoxicity, and tumor infiltration using both in vitro Matrigel-based assays and in vivo xenograft and syngeneic models enriched with cancer-associated fibroblasts (CAFs).

Results: MMP3 overexpression did not impair CAR-T cell proliferation, activation, or cytotoxicity. However, it significantly enhanced their capacity to invade through ECM and improved tumor cell killing in vitro. In CAF-enriched xenograft models, MMP3-engineered CAR-T cells demonstrated superior tumor infiltration, expansion, and antitumor activity. Notably, MMP3 overexpression rescued the function of B7H3 CAR-T cells in the stringent CAF-enriched tumor microenvironment, while conventional CAR-T cells showed limited activity. Importantly, MMP3 overexpression also conferred potent antitumor activity in an immunocompetent mouse model, underscoring its therapeutic benefit in a more physiologically and clinically related setting.

Conclusions: These findings suggest that MMP3 engineering is a simple yet effective strategy to overcome stromal barriers and enhance the efficacy of CAR-T cell therapy in solid tumors.

Purpose: This study was conducted to assess the clinical significance of programmed cell death-ligand 1 (PD-L1)-positive circulating tumor cells (CTCs) as predictive biomarkers for the efficacy of PD-(L)1 inhibitor-based treatment in advanced hepatocellular carcinoma (HCC).

Experimental design: We enrolled 59 patients with unresectable HCC who received immunotherapy-based treatment and analyzed CTCs, PD-L1⁺CTCs and molecules in peripheral blood. An innovative telomerase reverse transcriptase-based method was applied to detect specific CTCs. Kaplan-Meier analysis and Cox regression were used to evaluate clinical outcomes, such as progression-free survival (PFS) and overall survival (OS).

Results: CTCs were detected in 86.4% (51/59) of patients, with a PD-L1-positive rate of 83.7% (41/49). Compared with the "PD-L1⁺CTC Low" group, the "PD-L1⁺CTC High" group had significantly shorter PFS (median PFS: 7.72 vs 16.1 months, p=0.037) and shorter OS (median OS: 13.89 vs 36.97 months, p=0.031). The "PD-L1⁺CTC Fewer & Low" group had the longest survival outcomes (median PFS: 17.03 months, median OS: 36.97 months), whereas the "PD-L1⁺CTC More & High" group had the poorest outcomes (median PFS: 5.3 months, median OS: 10.77 months) (p<0.05). Multivariate analysis revealed that the PD-L1⁺CTC count and ratio were an independent predictor of PFS. Significant correlations were found between PD-L1⁺CTC and several immune-related molecules, such as immune checkpoint molecules (CD28, TIM-3, and CD80) and regulatory factors (BDNF, and BLTA).

Conclusions: PD-L1⁺CTCs are potential indicators correlating with the shorter PFS and OS of immunotherapy-based treatment in patients with advanced HCC. The "PD-L1⁺CTC Low & Fewer" classification was associated with better clinical outcomes and immune-related molecules.