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Purpose: With the development of immunotherapy research, the role of immune checkpoint blockade (ICB) in the treatment of cervical cancer has been emphasized, but many patients still can’t receive long-term benefits from ICB. Poly ADP ribose polymerase inhibitor (PARPi) has been proved to exert significant antitumor effects in multiple solid tumors. Whether cervical cancer patients obtain better benefits from the treatment regimen of PARPi combined with ICB remains unclear. Methods: The alteration of PD-L1 expression induced by niraparib in cervical cancer cells and its underlying mechanism were assessed by western blot and immunofluorescence and quantitative real-time polymerase chain reaction (qRT–PCR).The regulation of PTEN by KDM5A was confirmed using Chromatin immunoprecipitation (ChIP) assay and RNA interference. Analyzing the relationship between PD-L1 and immune effector molecules through searching online databases. Therapeutic efficacy of niraparib, PD-L1 blockade or combination was assessed in syngeneic tumor model. The changes of immune cells and cytokines in vivo was detected by immunohistochemistry (IHC) and qRT–PCR. Results: We found that niraparib upregulated PD-L1 expression and potentiated the antitumor effects of PD-L1 blockade in a murine cervical cancer model. Niraparib inhibited the Pten expression by increasing the abundance of KDM5A, which expanded PD-L1 abundance through activating the PI3K-AKT-S6K1 pathway. PD-L1 was positively correlated with immune effector molecules including TNF-α, IFN-γ, granzyme A and granzyme B based on biological information analysis. Niraparib increased the infiltration of CD8+ T cells and the level of IFN-γ, granzyme B in vivo. Conclusion: Our findings demonstrates the regulation of niraparib on local immune microenvironment of cervical cancer, and provides theoretical basis for supporting the combination of PARPi and PD-L1 blockade as a potential treatment for cervical cancer. [ABSTRACT FROM AUTHOR]

MSS/pMMR patients are unresponsive to PD-1/PD-L1 blockade in colorectal cancer (CRC), but the mechanisms are unclear. A better understanding of immunotherapy resistance in CRC may lead to more precise treatment and expand the benefit of immunotherapy to patients. In this study, we constructed mouse model of subcutaneous CRC tumor received anti-PD-L1 treatment with or without fusobacterium nucleatum (F. nucleatum) infection. Then we used single-cell RNA sequencing (scRNA-seq) to explore the comprehensive landscape of the tumor microenvironment (TME). Our data delineated the composition, subclonal diversity and putative function of distinct cells, tracked the developmental trajectory of tumor cells and highlighted cell-cell interactions. We found different compositions and functions of both tumor cells and immune cells. Single anti-PD-L1 monoclonal antibody (mAb) treated tumor exhibited two specific clusters which might be resistant to PD-L1 blockade. The accumulation of immune cells, including T cell, NK cell and pro-inflammatory macrophage subset in tumors infected with F. nucleatum may be one of the reasons for the increased sensitivity to PD-L1 blockade. Thus, targeting F. nucleatum to change the composition of tumor cell subclusters and enliven the immune response might help to overcome immune checkpoint blockade (ICB) resistance.

Abstract Background The efficacy of immune checkpoint blockade (ICB), in the treatment of hepatocellular carcinoma (HCC), is limited due to low levels of tumor-infiltrating T lymphocytes and deficient checkpoint blockade in this immunologically "cool" tumor. Thus, combination approaches are needed to increase the response rates of ICB and induce synergistic antitumor immunity. Methods Herein, we designed a pH-sensitive multifunctional nanoplatform based on layered double hydroxides (LDHs) loaded with siRNA to block the intracellular immune checkpoint NR2F6, together with the asynchronous blockade surface receptor PD-L1 to induce strong synergistic antitumor immunity. Moreover, photothermal therapy (PTT) generated by LDHs after laser irradiation modified an immunologically “cold” microenvironment to potentiate Nr2f6-siRNA and anti-PD-L1 immunotherapy. Flow cytometry was performed to assess the immune responses initiated by the multifunctional nanoplatform. Results Under the slightly acidic tumor extracellular environment, PEG detached and the re-exposed positively charged LDHs enhanced tumor accumulation and cell uptake. The accumulated siRNA suppressed the signal of dual protumor activity in both immune and H22 tumor cells by silencing the NR2F6 gene, which further reduced the tumor burden and enhanced systemic antitumor immunity. The responses include enhanced tumor infiltration by CD4+ helper T cells, CD8+ cytotoxic T cells, and mature dendritic cells; the significantly decreased level of immune suppressed regulator T cells. The therapeutic responses were also attributed to the production of IL-2, IFN-γ, and TNF-α. The prepared nanoparticles also exhibited potential magnetic resonance imaging (MRI) ability, which could serve to guide synergistic immunotherapy treatment. Conclusions In summary, the three combinations of PTT, NR2F6 gene ablation and anti-PD-L1 can promote a synergistic immune response to inhibit the progression of primary HCC tumors and prevent metastasis. This study can be considered a proof-of-concept for the targeting of surface and intracellular immune checkpoints to supplement the existing HCC immunotherapy treatments.

Induction of immunogenic cell death promotes antitumor immunity against cancer. However, majority of clinically-approved drugs are unable to elicit sufficient ICD. Here, our study revealed that mitochondria-targeted delivery of doxorubicin (DOX) massively amplified ICD via substantial generation of reactive oxygen species (ROS) after mitochondrial damage. The underlying mechanism behind increased ICD was further demonstrated to be ascribed to two pathways: (1) ROS elevated endoplasmic reticulum (ER) stress, leading to surface exposure of calreticulin; (2) ROS promoted release of various mitochondria-associated damage molecules including mitochondrial transcription factor A. Nevertheless, adaptive upregulation of PD-L1 was found after such ICD-inducing treatment. To overcome such immunosuppressive feedback, we developed a tumor stimuli-responsive nano vehicle to simultaneously exert mitochondrial targeted ICD induction and PD-L1 blockade. The nano vehicle was self-assembled from ICD-inducing copolymer and PD-L1 blocking copolymer, and possessed long-circulating property which contributed to better tumor accumulation and mitochondrial targeting. As a result, the nano vehicle remarkably activated antitumor immune responses and exhibited robust antitumor efficacy in both immunogenic and non-immunogenic tumor mouse models.

Glioblastoma (GBM) is the deadliest primary brain tumor and is generally resistant to immunotherapy because of severe dysfunction of T cells. Novel treatment options are critically needed to overcome the immunotherapy resistance of GBM. Here we demonstrate that Zika virus (ZIKV) treatment improves the efficacy of anti-PD ligand 1 (PD-L1) immunotherapy in GBM. We found that ZIKV induces a strong pro-inflammatory response and increases CD4+ and CD8+ T cell intratumoral infiltration and activation in GBM mouse models. ZIKV treatment of mice bearing GBM tumors inhibits tumor growth and prolongs survival. These therapeutic effects of ZIKV on GBM tumors are negated in mice depleted of T cells. Moreover, ZIKV dramatically promotes activation of the type I interferon signaling pathway in GBM cells. ZIKV treatment potently sensitizes GBM to PD-L1 blockade and provides significant and durable survival benefits. Our findings reveal that ZIKV overcomes the resistance of GBM to immune checkpoint blockade, which may lead to therapeutic applications of ZIKV in individuals with GBM receiving immunotherapy.

Tumor nanovaccines have potential applications in the prevention and treatment of malignant tumors. However, it remains a longstanding challenge in exploiting efficient nanocarriers for inducing potent specifically cellular immune responses. Toward this objective, we herein explore an intensive tumor immunotherapeutic strategy by combining mannosylated nanovaccines and gene regulated PD-L1 blockade for immune stimulation and killing activity. Here, we fabricate a mannose modified PLL-RT (Man-PLL-RT) mediated nanovaccines with dendritic cells (DCs) targeting capacity. Man-PLL-RT is capable of co-encapsulating with antigen (ovalbumin, OVA) and adjuvant (unmethylated cytosine-phosphate-guanine, CpG) by electrostatic interaction. This positively charged Man-PLL-RT/OVA/CpG nanovaccines can facilitate the endocytosis, maturation and cross presentation in DCs. However, the nanovaccines arouse limited inhibition of tumor growth, which is mainly due to the immunosuppressed microenvironment of tumors. Combining tumor nanovaccines with gene regulated PD-L1 blockade leads to an obvious tumor remission in B16F10 melanoma bearing mice. The collaborative strategy provides essential insights to boost the benefits of tumor vaccines by regulating the checkpoint blockade with gene therapy.

The use of immune checkpoint inhibitors to treat cancer resulted in unprecedented and durable clinical benefits. However, the response rate among patients remains rather modest. Previous work from our laboratory demonstrated the efficacy of using attenuated bacteria as immunomodulatory anti-cancer agents. The current study investigated the potential of utilizing a low dose of attenuated Salmonella typhimurium to enhance the efficacy of PD-L1 blockade in a relatively immunogenic model of colon cancer. The response of MC38 tumors to treatment with αPD-L1 monoclonal antibody (mAb) was variable, with only 30% of the mice being responsive. Combined treatment with αPD-L1 mAb and Salmonella resulted in 75% inhibition of tumor growth in 100% of animals. Mechanistically, the enhanced response correlated with a decrease in the percentage of tumor-associated granulocytic cells, upregulation in MHC class II expression by intratumoral monocytes and an increase in tumor infiltration by effector T cells. Collectively, these alterations resulted in improved anti-tumor effector responses and increased apoptosis within the tumor. Thus, our study demonstrates that a novel combination treatment utilizing attenuated Salmonella and αPD-L1 mAb could improve the outcome of immunotherapy in colorectal cancer.

T‐cell engagers (TCEs) represent a breakthrough in hematological malignancy treatment but are vulnerable to antigen escape and lack a vaccination effect. The "immunologically cold" solid tumor presents substantial challenges due to intratumor heterogeneity and an immunosuppressive tumor microenvironment (TME). Here, a methoxy poly(ethylene glycol) (mPEG)‐masked CD44×PD‐L1/CD3 trispecific T‐cell nanoengager loaded with the STING agonist c‐di‐AMP (CDA) (PmTriTNE@CDA) for the treatment of triple‐negative breast cancer (TNBC) is rationally designed. PmTriTNE@CDA shows tumor‐specific accumulation and is preferentially unmasked in response to a weakly acidic TME to prevent on‐target off‐tumor toxicity. The unmasked CD44×PD‐L1/CD3 trispecific T‐cell nanoengager (TriTNE) targets dual tumor‐associated antigens (TAAs) to redirect CD8+ T cells for heterogeneous TNBC lysis while achieving PD‐L1 blockade. PmTriTNE synergized with CDA to transform the cold tumor into a hot tumor, eradicate the large established TNBC tumor, and induce protective immune memory in a 4T1 orthotopic tumor model without causing obvious toxicity. PmTriTNE@CDA shows potent efficacy in cell line‐derived xenograft (CDX) and patient‐derived xenograft (PDX) mouse models. This study serves as a proof‐of‐concept demonstration of a nanobased TCEs strategy to expand therapeutic combinations that previously could not be achieved due to systemic toxicity with the aim of overcoming TNBC heterogeneity and immunotherapy resistance. [ABSTRACT FROM AUTHOR]

Checkpoint inhibitors targeting programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) have revolutionized cancer therapy across many indications including urothelial carcinoma (UC). Because many patients do not benefit, a better understanding of the molecular mechanisms underlying response and resistance is needed to improve outcomes. We profiled tumors from 2,803 UC patients from four late-stage randomized clinical trials evaluating the PD-L1 inhibitor atezolizumab by RNA sequencing (RNA-seq), a targeted DNA panel, immunohistochemistry, and digital pathology. Machine learning identifies four transcriptional subtypes, representing luminal desert, stromal, immune, and basal tumors. Overall survival benefit from atezolizumab over standard-of-care is observed in immune and basal tumors, through different response mechanisms. A self-supervised digital pathology approach can classify molecular subtypes from H&E slides with high accuracy, which could accelerate tumor molecular profiling. This study represents a large integration of UC molecular and clinical data in randomized trials, paving the way for clinical studies tailoring treatment to specific molecular subtypes in UC and other indications., Competing Interests: Declaration of interests All Genentech-affiliated authors are shareholders in Roche. H.H., S. Mariathasan., and R.B. are listed on a pending patent related to this work. P.G. is consulting for 4D Pharma, Aadi Bioscience, Asieris Pharmaceuticals, Astellas, AstraZeneca, BostonGene, Bristol Myers Squibb, CG Oncology, Dyania Health, Exelixis, Fresenius Kabi, G1 Therapeutics, Genentech, Gilead Sciences, Guardant Health, ImmunityBio, Infinity Pharmaceuticals, Janssen, Lucence, Merck KGaA, Mirati Therapeutics, MSD, Pfizer, PureTech, QED Therapeutics, Regeneron, Roche, Seattle Genetics, Silverback Therapeutics, Strata Oncology, UroGen Pharma, and receives institutional research funding from ALX Oncology, Acrivon Therapeutics, Bavarian Nordic, Bristol Myers Squibb, Clovis Oncology, Debiopharm Group, G1 Therapeutics, Gilead Sciences, GSK, Merck KGaA, Mirati Therapeutics, MSD, Pfizer, QED Therapeutics. E. Sokol. is an employee at Foundation Medicine and a shareholder in Roche. M.D.G. receives research funding from Bristol Myers Squibb, Novartis, Dendreon, Astra Zeneca, Merck, Genentech, and acts as Advisory Board/Consultant for Bristol Myers Squibb, Merck, Genentech, AstraZeneca, Pfizer, EMD Serono, SeaGen, Janssen, Numab, Dragonfly, GlaxoSmithKline, Basilea, UroGen, Rappta Therapeutics, Alligator, Silverback, Fujifilm, Curis, Gilead, Bicycle, Asieris, Abbvie, Analog Devices, Veracyte. T.P. receives honararia and research funding from Roche, Astellas, Seagen, MSD, Merck-Serono, BMS, Pfizer, Ipsen, AZ, Johnson and johnson, Mashup-Media, Exelixis, Eisai, Natera, FMI, Novartis, Bayer. J. Rosenberg is a Consultant for Aadi Bioscience; Alligator Bioscience; Astellas; AstraZeneca Pharmaceuticals LP; Boehringer Ingelheim Pharmaceuticals Inc; Bristol-Myers Squibb Company; Century Therapeutics Inc; EMD Serono Inc; Emergence Therapeutics; Genentech, a member of the Roche Group; Gilead Sciences Inc; Imvax Inc; Jiangsu Hengrui Medicine Co Ltd; Eli Lilly; Merck; Mirati Therapeutics Inc; Pfizer Inc; Seagen Inc; Tyra Biosciences, has Grant/Research support from Seagen Inc, Genentech/Roche, Astellas, Acrivon and receives honoraria from Pfizer Inc, EMD-Serono Inc, MJH Life Sciences, Research to Practice, Clinical Care Options. M.S.v.d.H. receives research funding from Bristol Myers Squibb, AstraZeneca, 4SC and Roche, and consultancy fees from Bristol Myers Squibb, Roche, Merck Sharp & Dohme, Merck, AstraZeneca, Pfizer, Janssen and Seattle Genetics, which were all paid to the Netherlands Cancer Institute., (Copyright © 2024 Elsevier Inc. All rights reserved.)

MSS/pMMR patients are unresponsive to PD-1/PD-L1 blockade in colorectal cancer (CRC), but the mechanisms are unclear. A better understanding of immunotherapy resistance in CRC may lead to more precise treatment and expand the benefit of immunotherapy to patients. In this study, we constructed mouse model of subcutaneous CRC tumor received anti-PD-L1 treatment with or without fusobacterium nucleatum ( F. nucleatum ) infection. Then we used single-cell RNA sequencing (scRNA-seq) to explore the comprehensive landscape of the tumor microenvironment (TME). Our data delineated the composition, subclonal diversity and putative function of distinct cells, tracked the developmental trajectory of tumor cells and highlighted cell-cell interactions. We found different compositions and functions of both tumor cells and immune cells. Single anti-PD-L1 monoclonal antibody (mAb) treated tumor exhibited two specific clusters which might be resistant to PD-L1 blockade. The accumulation of immune cells, including T cell, NK cell and pro-inflammatory macrophage subset in tumors infected with F. nucleatum may be one of the reasons for the increased sensitivity to PD-L1 blockade. Thus, targeting F. nucleatum to change the composition of tumor cell subclusters and enliven the immune response might help to overcome immune checkpoint blockade (ICB) resistance., Competing Interests: ☒ The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Ltd.)

Background: The efficacy of immune checkpoint blockade (ICB), in the treatment of hepatocellular carcinoma (HCC), is limited due to low levels of tumor-infiltrating T lymphocytes and deficient checkpoint blockade in this immunologically "cool" tumor. Thus, combination approaches are needed to increase the response rates of ICB and induce synergistic antitumor immunity. Methods: Herein, we designed a pH-sensitive multifunctional nanoplatform based on layered double hydroxides (LDHs) loaded with siRNA to block the intracellular immune checkpoint NR2F6, together with the asynchronous blockade surface receptor PD-L1 to induce strong synergistic antitumor immunity. Moreover, photothermal therapy (PTT) generated by LDHs after laser irradiation modified an immunologically "cold" microenvironment to potentiate Nr2f6-siRNA and anti-PD-L1 immunotherapy. Flow cytometry was performed to assess the immune responses initiated by the multifunctional nanoplatform. Results: Under the slightly acidic tumor extracellular environment, PEG detached and the re-exposed positively charged LDHs enhanced tumor accumulation and cell uptake. The accumulated siRNA suppressed the signal of dual protumor activity in both immune and H22 tumor cells by silencing the NR2F6 gene, which further reduced the tumor burden and enhanced systemic antitumor immunity. The responses include enhanced tumor infiltration by CD4+ helper T cells, CD8+ cytotoxic T cells, and mature dendritic cells; the significantly decreased level of immune suppressed regulator T cells. The therapeutic responses were also attributed to the production of IL-2, IFN-γ, and TNF-α. The prepared nanoparticles also exhibited potential magnetic resonance imaging (MRI) ability, which could serve to guide synergistic immunotherapy treatment. Conclusions: In summary, the three combinations of PTT, NR2F6 gene ablation and anti-PD-L1 can promote a synergistic immune response to inhibit the progression of primary HCC tumors and prevent metastasis. This study can be considered a proof-of-concept for the targeting of surface and intracellular immune checkpoints to supplement the existing HCC immunotherapy treatments. [ABSTRACT FROM AUTHOR]

Abstract Background Recent studies have demonstrated that multidrug resistance (MDR) is a critical factor in the low efficacy of cancer chemotherapy. The main mechanism of MDR arises from the overexpression of P-glycoprotein (P-gp), which actively enhances drug efflux and limits the effectiveness of chemotherapeutic agents. Results In this study, we fabricated a “combo” nanoagent equipping with triple synergistic strategies for enhancing antitumor efficacy against MDR cells. Tumor homing-penetrating peptide endows the nanosystem with targeting and penetrating capabilities in the first stage of tumor internalization. The abundant amine groups of polyethylenimine (PEI)-modified nanoparticles then trigger a proton sponge effect to promote endo/lysosomal escape, which enhances the intracellular accumulation and retention of anticancer drugs. Furthermore, copper tetrakis(4-carboxyphenyl)porphyrin (CuTCPP) encapsulated in the nanosystem, effectively scavenges endogenous glutathione (GSH) to reduce the detoxification mediated by GSH and sensitize the cancer cells to drugs, while simultaneously serving as a photoacoustic imaging (PAI) contrast agent for image visualization. Moreover, we also verify that these versatile nanoparticles in combination with PD-1/PD-L1 blockade therapy can not only activate immunological responses but also inhibit P-gp expression to obliterate primary and metastatic tumors. Conclusion This work shows a significant enhancement in therapeutic efficacy against MDR cells and syngeneic tumors by using multiple MDR reversing strategies compared to an equivalent dose of free paclitaxel. Graphic Abstract

Induction of immunogenic cell death promotes antitumor immunity against cancer. However, majority of clinically-approved drugs are unable to elicit sufficient ICD. Here, our study revealed that mitochondria-targeted delivery of doxorubicin (DOX) massively amplified ICD via substantial generation of reactive oxygen species (ROS) after mitochondrial damage. The underlying mechanism behind increased ICD was further demonstrated to be ascribed to two pathways: (1) ROS elevated endoplasmic reticulum (ER) stress, leading to surface exposure of calreticulin; (2) ROS promoted release of various mitochondria-associated damage molecules including mitochondrial transcription factor A. Nevertheless, adaptive upregulation of PD-L1 was found after such ICD-inducing treatment. To overcome such immunosuppressive feedback, we developed a tumor stimuli-responsive nano vehicle to simultaneously exert mitochondrial targeted ICD induction and PD-L1 blockade. The nano vehicle was self-assembled from ICD-inducing copolymer and PD-L1 blocking copolymer, and possessed long-circulating property which contributed to better tumor accumulation and mitochondrial targeting. As a result, the nano vehicle remarkably activated antitumor immune responses and exhibited robust antitumor efficacy in both immunogenic and non-immunogenic tumor mouse models. Insulin-loaded milk-derived exosomes overcame multiple oral drug delivery barriers in the meanwhile by different mechanisms, exerting excellent hypoglycemic effect on type I diabetic rats. [Display omitted] [ABSTRACT FROM AUTHOR]

Immune checkpoint inhibitor therapy combined with chemotherapy is safe and effective in treating advanced esophageal carcinoma; however, some patients still experience tumor progression and/or metastasis. Whether the addition of radiotherapy to immunotherapy combined with chemotherapy improves the prognosis of patients with advanced/metastatic esophageal carcinoma needs to be investigated. In the present study, we developed a protocol for our clinical trial indicating that toripalimab combined with induction chemotherapy followed by chemoradiotherapy can safely prolong survival in patients with stage IV esophageal carcinoma. This open-label, single-arm, phase II trial will include patients with unresectable stage IV esophageal squamous cell carcinoma who have not received prior systemic therapy. The patients will be treated with two cycles of toripalimab (240 mg, 1 day before chemotherapy, Q3W) combined with induction chemotherapy (paclitaxel, 135–175 mg/m2 + carboplatin, area under the curve = 4–6, day 1, intravenous, Q3W). Thereafter, they will undergo two cycles of the aforementioned treatment with concurrent radiotherapy (30–50 Gy in 15–25 fractions), followed by toripalimab (240 mg, day 1, Q3W) for 1 year. The primary outcome measure will be progression-free survival; the secondary outcome measures will include the objective response rate, disease control rate, duration of remission, 1- and 2-year overall survival rates, safety and tolerability, and changes in health-related quality of life. The study protocol was approved by the Ethics Committee of Sichuan Cancer Hospital (SCCHEC-02-2021-021). The trial is underway in accordance with the Declaration of Helsinki. Clinical Trial Registration: http://www.chictr.org.cn/showproj.aspx?proj=126830 , identifier ChiCTR2100046715. [ABSTRACT FROM AUTHOR]

Immune checkpoint inhibitor therapy combined with chemotherapy is safe and effective in treating advanced esophageal carcinoma; however, some patients still experience tumor progression and/or metastasis. Whether the addition of radiotherapy to immunotherapy combined with chemotherapy improves the prognosis of patients with advanced/metastatic esophageal carcinoma needs to be investigated. In the present study, we developed a protocol for our clinical trial indicating that toripalimab combined with induction chemotherapy followed by chemoradiotherapy can safely prolong survival in patients with stage IV esophageal carcinoma. This open-label, single-arm, phase II trial will include patients with unresectable stage IV esophageal squamous cell carcinoma who have not received prior systemic therapy. The patients will be treated with two cycles of toripalimab (240 mg, 1 day before chemotherapy, Q3W) combined with induction chemotherapy (paclitaxel, 135–175 mg/m2 + carboplatin, area under the curve = 4–6, day 1, intravenous, Q3W). Thereafter, they will undergo two cycles of the aforementioned treatment with concurrent radiotherapy (30–50 Gy in 15–25 fractions), followed by toripalimab (240 mg, day 1, Q3W) for 1 year. The primary outcome measure will be progression-free survival; the secondary outcome measures will include the objective response rate, disease control rate, duration of remission, 1- and 2-year overall survival rates, safety and tolerability, and changes in health-related quality of life. The study protocol was approved by the Ethics Committee of Sichuan Cancer Hospital (SCCHEC-02-2021-021). The trial is underway in accordance with the Declaration of Helsinki.Clinical Trial Registrationhttp://www.chictr.org.cn/showproj.aspx?proj=126830, identifier ChiCTR2100046715.

Background: A functional cure for chronic HBV could be achieved by boosting HBV-specific immunity. In vitro studies show that immunotherapy could be an effective strategy. However, these studies include strategies to enrich HBV-specific CD8 T cells, which could alter the expression of the anti-PD-1/anti-PD-L1 antibody targets. Our aim was to determine the efficacy of PD-L1 blockade ex vivo. Methods: HBV-specific CD8 T cells were characterized ex vivo by flow cytometry for the simultaneous analysis of six immune populations and 14 activating and inhibitory receptors. Ex vivo functionality was quantified by ELISpot and by combining peptide pool stimulation, dextramers and intracellular flow cytometry staining. Results: The functionality of HBV-specific CD8 T cells is associated with a higher frequency of cells with low exhaustion phenotype (LAG3-TIM3-PD-1+), independently of the clinical parameters. The accumulation of HBV-specific CD8 T cells with a functionally exhausted phenotype (LAG3+TIM3+PD-1+) is associated with lack of ex vivo functionality. PD-L1 blockade enhanced the HBV-specific CD8 T cell response only in patients with lower exhaustion levels, while response to PD-L1 blockade was abrogated in patients with higher frequencies of exhausted HBV-specific CD8 T cells. Conclusion: Higher levels of functionally exhausted HBV-specific CD8 T cells are associated with a lack of response that cannot be restored by blocking the PD-1:PD-L1 axis. This suggests that the clinical effectiveness of blocking the PD-1:PD-L1 axis as a monotherapy may be restricted. Combination strategies, potentially including the combination of anti-LAG-3 with other anti-iR antibodies, will likely be required to elicit a functional cure for patients with high levels of functionally exhausted HBV-specific CD8 T cells. [ABSTRACT FROM AUTHOR]

BackgroundA functional cure for chronic HBV could be achieved by boosting HBV-specific immunity. In vitro studies show that immunotherapy could be an effective strategy. However, these studies include strategies to enrich HBV-specific CD8 T cells, which could alter the expression of the anti-PD-1/anti-PD-L1 antibody targets. Our aim was to determine the efficacy of PD-L1 blockade ex vivo.MethodsHBV-specific CD8 T cells were characterized ex vivo by flow cytometry for the simultaneous analysis of six immune populations and 14 activating and inhibitory receptors. Ex vivo functionality was quantified by ELISpot and by combining peptide pool stimulation, dextramers and intracellular flow cytometry staining.ResultsThe functionality of HBV-specific CD8 T cells is associated with a higher frequency of cells with low exhaustion phenotype (LAG3-TIM3-PD-1+), independently of the clinical parameters. The accumulation of HBV-specific CD8 T cells with a functionally exhausted phenotype (LAG3+TIM3+PD-1+) is associated with lack of ex vivo functionality. PD-L1 blockade enhanced the HBV-specific CD8 T cell response only in patients with lower exhaustion levels, while response to PD-L1 blockade was abrogated in patients with higher frequencies of exhausted HBV-specific CD8 T cells.ConclusionHigher levels of functionally exhausted HBV-specific CD8 T cells are associated with a lack of response that cannot be restored by blocking the PD-1:PD-L1 axis. This suggests that the clinical effectiveness of blocking the PD-1:PD-L1 axis as a monotherapy may be restricted. Combination strategies, potentially including the combination of anti-LAG-3 with other anti-iR antibodies, will likely be required to elicit a functional cure for patients with high levels of functionally exhausted HBV-specific CD8 T cells.

Purpose: Apatinib, an antiangiogenic drug, has shown beneficial effects only in a fraction of advanced gastric cancer (GC) patients. Given the recent success of immunotherapies, combination of apatinib with immune checkpoint inhibitor may provide sustained and potent antitumor responses. Methods: Immunocompetent mice with subcutaneous MFC tumors grown were given a combination of apatinib and anti-PD-L1 antibody therapy. GC tissues from patients undergoing curative resection in China were collected, and the density of HEVs, MSI status and tumor-infiltrated lymphocytes were analyzed by immunohistochemical staining. Results: Combined apatinib and PD-L1 blockade therapy synergistically delayed tumor growth and increased survival in MFC-bearing immunocompetent mice. The combination therapy promoted antitumor immunity by increasing the ratio of CD8+ cytotoxic T cells to Foxp3+ Treg cells, the accumulation of CD20+ B cells and the Th1/Th2 cytokine ratio (IFN-γ/IL-10). The combination therapy induced the formation of HEVs through activation of LTβR signaling, thus promoting CD8+ cytotoxic T cell and CD20+ B cell infiltration in tumors. In clinical GC samples, the density of HEVs positively correlated with the intratumoral infiltration of CD8+ cytotoxic T cells and CD20+ B cells. MSI-high GC showed a higher density of HEVs, CD8+ cytotoxic T cells and CD20+ B cells than MSS/MSI-low GC. GC patients with high densities of HEVs, CD8+ cytotoxic T cells and CD20+ B cells had an improved prognosis with superior overall survival. Conclusion: Combining apatinib with PD-L1 blockade treatment synergistically enhances antitumor immune responses and promotes HEV formation in GC. [ABSTRACT FROM AUTHOR]

Background: Recent studies have demonstrated that multidrug resistance (MDR) is a critical factor in the low efficacy of cancer chemotherapy. The main mechanism of MDR arises from the overexpression of P-glycoprotein (P-gp), which actively enhances drug efflux and limits the effectiveness of chemotherapeutic agents. Results: In this study, we fabricated a "combo" nanoagent equipping with triple synergistic strategies for enhancing antitumor efficacy against MDR cells. Tumor homing-penetrating peptide endows the nanosystem with targeting and penetrating capabilities in the first stage of tumor internalization. The abundant amine groups of polyethylenimine (PEI)-modified nanoparticles then trigger a proton sponge effect to promote endo/lysosomal escape, which enhances the intracellular accumulation and retention of anticancer drugs. Furthermore, copper tetrakis(4-carboxyphenyl)porphyrin (CuTCPP) encapsulated in the nanosystem, effectively scavenges endogenous glutathione (GSH) to reduce the detoxification mediated by GSH and sensitize the cancer cells to drugs, while simultaneously serving as a photoacoustic imaging (PAI) contrast agent for image visualization. Moreover, we also verify that these versatile nanoparticles in combination with PD-1/PD-L1 blockade therapy can not only activate immunological responses but also inhibit P-gp expression to obliterate primary and metastatic tumors. Conclusion: This work shows a significant enhancement in therapeutic efficacy against MDR cells and syngeneic tumors by using multiple MDR reversing strategies compared to an equivalent dose of free paclitaxel. [ABSTRACT FROM AUTHOR]

Respiratory syncytial virus (RSV) is the major cause of lower respiratory tract infections in children under 1 year. RSV vaccines are currently unavailable, and children suffering from multiple reinfections by the same viral strain fail to develop protective responses. Although RSV‐specific antibodies can be detected upon infection, these have limited neutralizing capacity. Follicular helper T (Tfh) cells are specialized in providing signals to B cells and help the production and affinity maturation of antibodies, mainly via interleukin (IL) 21 secretion. In this study, we evaluated whether RSV could inhibit Tfh responses. We observed that Tfh cells fail to upregulate IL‐21 production upon RSV infection. In the lungs, RSV infection downregulated the expression of IL‐21/interleukin‐21 receptor (IL‐21R) in Tfh cells and upregulated programmed death‐ligand 1 (PD‐L1) expression in dendritic cells (DCs) and B cells. PD‐L1 blockade during infection recovered IL‐21R expression in Tfh cells and increased the secretion of IL‐21 in a DC‐dependent manner. IL‐21 treatment decreased RSV viral load and lung inflammation, inducing the formation of tertiary lymphoid organs in the lung. It also decreased regulatory follicular T cells, and increased Tfh cells, B cells, antibody avidity and neutralization capacity, leading to an overall improved anti‐RSV humoral response in infected mice. Passive immunization with purified immunoglobulin G from IL‐21‐treated RSV‐infected mice protected against RSV infection. Our results unveil a pathway by which RSV affects Tfh cells by increasing PD‐L1 expression on antigen‐presenting cells, highlighting the importance of an IL‐21–PD‐L1 axis for the generation of protective responses to RSV infection. [ABSTRACT FROM AUTHOR]

The architecture of multivalent polymers exerts an amplified interaction between attached ligands and targets. In current research, we reveal that a dendronized polymer augments the efficacy of an oncolytic peptide (OP; KKWWKKWDipK) for immunotherapy by exploiting (i) "flexible" linear polymer backbone to facilitate interactions with biomembrane systems, and (ii) "rigid" dendronized side chains to enhance the membrane lytic property. We show that a dendronized N -(2-hydroxypropyl)methacrylamide (HPMA) polymer-OP conjugate (PDOP) adopts α-helix secondary structure and induces robust immunogenic cell death (ICD) in cancer cells as characterized by multiple damage-associated molecular patterns (DAMPs) which include intracellular formation of reactive oxygen species (ROS) and surface exposure of calreticulin (CRT). These events convert immunosuppressive 4T1 tumor to an immunoresponsive one by recruiting CD8+ cytotoxic T cells into tumor beds. Combination of PDOP with anti-PD-L1 immune checkpoint blockade (ICB) increases the number of effector memory T cells and completely eradicates 4T1 tumors in mice. Our findings suggest that PDOP is a promising platform for oncolytic immunotherapy. Graphic abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Nanomedicine-based chemoimmunotherapy has shown a great potential for cancer therapies application in recent years. However, most nanoparticles still face a problem of low accumulation and limited penetration of chemotherapeutic drugs and immunotherapeutic drugs into solid tumors. Here, we developed a tumor microenvironment (TME)-activable therapeutic peptide-conjugated prodrug nanoparticle for enhanced tumor penetration and synergistic antitumor effects of chemotherapy and immune checkpoint blockade therapy. The prodrug nanoparticle is composed of a short D-peptide antagonist of PD-L1 (DPPA) conjugated doxorubicin (DOX) prodrug and a PEGylated DOX prodrug, which can dissociate into small DOX nanoparticles (<30 nm) and release DPPA antagonist in TME. The prodrug nanoparticles could co-deliver DOX and DPPA antagonist by one nanocarrier and improve tumor accumulation and penetration of the prodrug nanoparticels via a transcytosis process. It is demonstrated that co-delivery of DOX and DPPA antagonist directly killed tumor cells, promoted the tumor-infiltrating cytotoxic T lymphocytes, reduced the tumor-infiltrating regulatory T cells, and elicited a long-term immune memory effect to prevent tumor recurrence and metastasis. This TME-activable prodrug nanoparticle holds promise as a co-delivery nanoplatform for the improved chemoimmunotherapy of solid tumors. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Immune checkpoint blockade (ICB) therapy has been approved for breast cancer (BC), but clinical response rates are limited. Recent studies have shown that commensal microbes colonize a variety of tumors and are closely related to the host immune system response. Here, we demonstrated that Fusobacterium nucleatum ( F.n ), which is prevalent in BC, creates an immunosuppressive tumor microenvironment (ITME) characterized by a high-influx of myeloid cells that hinders ICB therapy. Administering the antibiotic metronidazole in BC can deplete F.n and remodel the ITME. To prevent an imbalance in the systemic microbiota caused by antibiotic administration, we designed a biomimetic nanovehicle for on-site antibiotic delivery inspired by F.n homing to BC. Additionally, ferritin-nanocaged doxorubicin was coloaded into this nanovehicle, as immunogenic chemotherapy has shown potential for synergy with ICB. It has been demonstrated that this biomimetic nanovehicle can be precisely homed to BC and efficiently eliminate intratumoral F.n without disrupting the diversity and abundance of systemic microbiota. This ultimately remodels the ITME, improving the therapeutic efficacy of the PD-L1 blocker with a tumor inhibition rate of over 90% and significantly extending the median survival of 4T1 tumor-bearing mice.

In chronic HIV infection, virus-specific cytotoxic CD8 T cells showed expression of checkpoint receptors and impaired function. Therefore, restoration of CD8 T-cell function is critical in cure strategies. Here, we show that in vitro blockade of programmed cell death ligand 1 (PD-L1) by an anti-PD-L1 antibody (avelumab) in combination with recombinant human interleukin-15 (rhIL-15) synergistically enhanced cytokine secretion by proliferating HIVGag-specific CD8 T cells. In addition, these CD8 T cells have a CXCR3+PD1−/low phenotype, suggesting a potential to traffic into peripheral tissues. In vitro, proliferating CD8 T cells express PD-L1 suggesting that anti-PD-L1 treatment also targets virus-specific CD8 T cells. Together, these data indicate that rhIL-15/avelumab combination therapy could be a useful strategy to enhance CD8 T-cell function in cure strategies. [ABSTRACT FROM AUTHOR]

• Synthesize defect-rich LDH nanosheets as inorganic photosensitizers for NIR III PDT. • The high concentration of H 2 O 2 in TME acted as the initial "key" to unlock the outer "doors" of hybrid CM-TK membrane shell. • The low pH would be the second "key" to trigger re-exposed pHLIP mediated GSDMD-N dependent pyroptosis. • Evoked pyroptosis together with anti-PD-L1 blockade therapy activated adaptive immunity in HCC. Immune checkpoint blockade (ICB) therapy for hepatocellular carcinoma (HCC) is limited due to its immunosuppressive tumor microenvironment (TME). Proinflammatory pyroptosis as a new schedule can induce immunogenic cell death (ICD), thereby reversing immunosuppressive TME and improving ICB efficiency. Herein, we report an acid-etched layered double hydroxides nanosheets (E-LDH)-based smart nanoplatforms armed with H 2 O 2 /pH dual "doorkeepers" (denoted as CTEP) targeting HCC to realize membrane-anchored photodynamic therapy (PDT) and evoke potent pyroptosis to effectively improve anti-tumor immunity. The hybrid Hepa1-6 cancer cell membrane (CM) and thylakoid (TK) membrane is cloaked on the surface of pH-(low)-insertion peptide (pHLIP) modified E-LDH to obtain CTEP. Once CTEP nanoplatforms arrive at tumor regions, the dual "doorkeepers" will orderly open to perform PDT precisely. Given the fact that TK membranes have the catalase mimetic function, CTEP is able to respond to high concentrations of H 2 O 2 in TME and rupture the hybrid CM-TK membrane to expose pH-sensitive peptide pHLIP. Membrane-localized PDT can induce gasdermin-D (GSDMD) mediated pyroptosis, effectively stimulating tumor immunogenicity. Pyroptotic cell death releases damage-associated molecular patterns (DAMPs) and consequently robust IaCB ability. CTEP-evoked pyroptosis together with anti-PD-L1 blockade therapy activates adaptive immunity in HCC, successfully inhibiting the progression of primary and distant HCC tumors with mitigation of the side effects. This research has demonstrated that CTEP with excellent biocompatibility and homologous targeting ability can act as a potent pyroptosis inducer to improve immune efficacy. The combination of PDT and immunotherapy via a photo-pyroptosis pathway can be a smart strategy for HCC treatment. [ABSTRACT FROM AUTHOR]

Cancer patients having anti-programmed cell death-1 (PD-1)/PD ligand 1 (L1)-unresponsive tumors may benefit from advanced immunotherapy. Double-stranded RNA triggers dendritic cell (DC) maturation to cross-prime antigen-specific cytotoxic T lymphocytes (CTLs) via Toll-like receptor 3 (TLR3). The TLR3-specific RNA agonist, ARNAX, can induce anti-tumor CTLs without systemic cytokine/interferon (IFN) production. Here, we have developed a safe vaccine adjuvant for cancer that effectively implements anti-PD-L1 therapy. Co-administration of ARNAX with a tumor-associated antigen facilitated tumor regression in mouse models, and in combination with anti-PD-L1 antibody, activated tumor-specific CTLs in lymphoid tissues, enhanced CTL infiltration, and overcame anti-PD-1 resistance without cytokinemia. The TLR3-TICAM-1-interferon regulatory factor (IRF)3-IFN-β axis in DCs exclusively participated in CD8+ T cell cross-priming. ARNAX therapy established Th1 immunity in the tumor microenvironment, upregulating genes involved in DC/T cell/natural killer (NK) cell recruitment and functionality. Human ex vivo studies disclosed that ARNAX+antigen induced antigen-specific CTL priming and proliferation in peripheral blood mononuclear cells (PBMCs), supporting the feasibility of ARNAX for potentiating anti-PD-1/PD-L1 therapy in human vaccine immunotherapy.

In metastatic urothelial cancer (mUC), cisplatin versus carboplatin leads to durable disease control in a subset of patients. The IMvigor130 trial reveals more favorable effects with atezolizumab combined with gemcitabine and cisplatin (GemCis) versus gemcitabine and carboplatin (GemCarbo). This study investigates the immunomodulatory effects of cisplatin as a potential explanation for these observations. Our findings indicate that improved outcomes with GemCis versus GemCarbo are primarily observed in patients with pretreatment tumors exhibiting features of restrained adaptive immunity. In addition, GemCis versus GemCarbo ± atezolizumab induces transcriptional changes in circulating immune cells, including upregulation of antigen presentation and T cell activation programs. In vitro experiments demonstrate that cisplatin, compared with carboplatin, exerts direct immunomodulatory effects on cancer cells, promoting dendritic cell activation and antigen-specific T cell killing. These results underscore the key role of immune modulation in cisplatin's efficacy in mUC and highlight the importance of specific chemotherapy backbones in immunotherapy combination regimens., Competing Interests: Declaration of interests M.D.G. has received grants or contracts from Bristol Myers Squibb, Novartis, Dendreon, AstraZeneca, and Merck; and has received consulting fees from Bristol Myers Squibb, Merck, Genentech Inc., AstraZeneca, Pfizer, EMD Serono, Seagen, Janssen, Numab, Dragonfly, GlaxoSmithKline, Basilea, UroGen, RapptaTherapeutics, Alligator, Silverback, Fujifilm, and Curis. X.G., D.R., A.S.R., H.M.S., R.B., K.Y., E.V., R.H., C.-J.H., Y.L., D.V., P.W., I.M., S.S., R.J., and S.M. are employees of Genentech Inc., and hold stocks or stock options in Roche/Genentech Inc. H.L. is an employee of Hoffmann-La Roche Ltd, Canada. L.W., J.Z., and H.Y. are employees of Sema4. E.H. was employed at Immunai during study conduct. R.H.H. and E. Kiner are employees of Immunai. A.B. has served as a consultant or advisor to Roche, Bristol Myers Squibb, MSD, and Pfizer; has received honoraria from Bristol Myers Squibb, MSD, and Pfizer; and has received educational and research grants from Pfizer, Pierre-Fabre, and Bristol Myers Squibb. M.D.S. has received consulting fees from AAA, Accord, Amgen, Astellas, AstraZeneca, Basilea, Bayer, Bioclin, Bristol Myers Squibb, Eisai, Ferring, Immunomedics, Ipsen, Janssen, MSD, Merck, Novartis, Pfizer, Pierre Fabre Oncology, Roche, Sandoz, Sanofi, and Seagen; has received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from AAA, Accord, Amgen, Astellas, AstraZeneca, Basilea, Bayer, Bioclin, Bristol Myers Squibb, Eisai, Ferring, Immunomedics, Ipsen, Janssen, MSD, Merck, Novartis, Pfizer, Pierre Fabre Oncology, Roche, Sandoz, Sanofi, and Seagen; has received support for attending meetings and/or travel from AAA, Accord, Amgen, Astellas, AstraZeneca, Basilea, Bayer, Bioclin, Bristol Myers Squibb, Eisai, Ferring, Immunomedics, Ipsen, Janssen, MSD, Merck, Novartis, Pfizer, Pierre Fabre Oncology, Roche, Sandoz, Sanofi, and Seagen; has participated in a Data Safety Monitoring Board or Advisory Board for Roche, Orion, and CR-UK; and has other financial or non-financial interests by having worked on the ESMO guidelines on bladder cancer and the German S3 Leitlinie Blasenkarzinom. I.D.D. has participated in a Data Safety Monitoring Board or Advisory Board for Roche/Genentech Inc. (WO30070 [IMvigor130] international steering committee; unpaid) and Merck/Pfizer (APAC GU Advisory Board; unpaid: honoraria are invoiced by and paid directly to ANZUP Cancer Trials Group); and has a leadership or fiduciary role in the ANZUP Cancer Trials Group (as a Director and Board Chair; unpaid). J.A.A. has received third-party service as collaboration in the selection, and management of administrative requirements for the participation of SOGUG centers in the study from SOGUG during the conduct of the study; speaking or consulting fees from Bristol Myers Squibb, MSD, Roche, Astellas, Janssen Cilag, Pfizer, Novartis, and Bayer outside the submitted work; travel support from Bristol Myers Squibb, MSD, Roche, and Janssen Cilag outside the submitted work; research funding (from SOGUG) outside the submitted work from Bristol Myers Squibb, Novartis, and Pierre Fabre; and has participated in industry-sponsored clinical trials for Bristol Myers Squibb, MSD, Roche, Astellas, Janssen Cilag, Pfizer, and Novartis outside the submitted work. E. Kikuchi has received grants or contracts (through his institution) from Takeda, Nippon Kayaku, and Taiho; has received consulting fees from Chugai, Nippon Kayaku, MSD, Takeda, Pfizer, Astellas, Bristol Myers Squibb, and Yansen; has received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Takeda, Nippon Kayaku, and Taiho; and has received consulting fees from Chugai, Nippon Kayaku, MSD, Takeda, Taiho, AstraZeneca, Pfizer, Astellas, Bristol Myers Squibb, and Yansen. S.B. is an employee of Roche Products Ltd, UK, holds stocks or stock options in Roche, and has other financial or non-financial interests in Roche. C.L. is an employee of Roche Products Ltd, UK, holds stocks or stock options in Roche, and has other financial or non-financial interests in Roche. P.C.B. has participated in advisory boards for Janssen, Merck, Roche/Genentech Inc., Bristol Myers Squibb, Urogen, EMD Serono, Bayer, Astellas, AbbVie, AstraZeneca, Ferring, H3-Biomedicine, Sanofi, Pfizer, Prokarium, Protara Therapeutics, Stimit, and Verity; has received payment or honoraria as a speaker from Janssen, Bayer, Ferring, H3-Biomedicine, and Pfizer; has participated in clinical trials for Roche/Genentech Inc., Bristol Myers Squibb, and AstraZeneca; and has received non-financial support (scientific collaboration on bladder cancer genomics/transcriptomics) from Decipher Biosciences/Veracyte. E.G. has received grants or contracts from Astellas, AstraZeneca, Ipsen, Merck KGaA, and Pfizer; has received payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Astellas, AstraZeneca, Bayer, Bristol Myers Squibb, Eisai, Esteve, Ipsen, Janssen, Lilly, Merck KGaA, MSD, Pfizer, Raffo, and Roche; and has received support for attending meetings and/or travel from Roche, AstraZeneca, Bristol Myers Squibb, Pfizer, and Merck KGaA., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Prior studies have demonstrated that fibroblast receptor 3 (FGFR3)-mutant urothelial cancers (UCs) are associated with decreased T-cell infiltration. As FGFR3 mutations are enriched in luminal-like UC and luminal-like UC has been shown to be relatively less responsive to PD-1/PD-L1 inhibition (checkpoint inhibition [CPI]), these data have led to the speculation that FGFR3 mutations may be causally related to poor T-cell infiltration and that UC patients harboring FGFR3 mutations may be suboptimal candidates for CPI. Using data derived from two clinical trials exploring CPI in metastatic UC, we demonstrate no statistically significant difference in response rates in patients with FGFR3 -mutant versus wild-type UC. We present hypothesis-generating data, suggesting that similar response rates may be explained by a "balancing out" of previously identified independent positive and negative predictors of CPI sensitivity; that is, compared with FGFR3 wild-type UC, FGFR3 -mutant UC is associated with a similar tumor mutational burden, lower T-cell infiltration, but also lower stromal/transforming growth factor beta (TGF-β) signals. Based on our findings, FGFR3 mutation status is not a biomarker of resistance to CPI. Indeed, the single-agent activity of both FGFR3 inhibitors and CPI in FGFR3 -mutant UC, and potential non-cross resistance provide a strong pragmatic rationale for combination approaches. In this report, we examined the impact of a mutated gene found in a subset of urothelial cancers on response to treatment with immunotherapy. We found that patients with tumors harboring mutations in the gene FGFR3 respond to immunotherapy similarly to patients without such mutations. Despite FGFR3 alterations in urothelial cancers being associated with decreased inferred T-cell infiltration, in two large clinical trial cohorts, patients with FGFR3-mutant metastatic urothelial cancers responded to immune checkpoint blockade similarly to patients with FGFR3 wild-type tumors. This disconnect may be related to decreased stromal-mediated resistance to immune checkpoint blockade in FGFR3-altered urothelial cancer, suggesting a potential "balancing out" of positive and negative predictors of immune checkpoint blockade sensitivity. [ABSTRACT FROM AUTHOR]

Owing to the limited therapeutic efficacy of glioma vaccines, new strategies are required to improve cancer vaccines. Our study aimed to assess the therapeutic efficacy of a glioma vaccine called STDENVANT. This vaccine, comprising glioma stem‐like cell (GSC) lysate, dendritic cells (DCs), and Toll‐like receptor (TLR) 9 agonist CpG motif‐containing oligodeoxynucleotides (CpG ODNs), was assessed using a GL261‐C57BL/6 orthotopic mouse model of glioma. STDENVANT markedly improved survival and tumor regression by enhancing anti‐tumor immune function. Moreover, STDENVANT upregulated programmed death 1 (PD‐1) and its ligand PD‐L1 on effector T cells, DCs, and glioma tissues, resulting in the accumulation of regulatory T (Treg) cells in the brain and lymph nodes. Combinatorial administration of anti‐PD‐L1 antibody and STDENVANT conferred a greater survival advantage and decreased the Treg cell population in the brain. The present results indicate that PD‐L1 blockade can promote tumor regression via STDENVANT in a mouse model of glioma, and combinatorial administration of anti‐PD‐L1 antibody and STDENVANT increases the therapeutic anti‐tumor efficacy of treatment. What's new? Vaccines based on dendritic cells harbouring glioma stem‐like cell (GSC)‐associated antigens are a promising therapeutic avenue against glioma, but efficacy remains limited. Here, the authors assessed the efficacy of a novel glioma vaccine called STDENVANT containing GSC lysate, dendritic cells, and CpG adjuvant. STDENVANT improved survival and tumor regression by enhancing anti‐tumor immune function in an orthotopic mouse model of glioma. Moreover, addition of anti‐PD‐L1 mAb enhanced the therapeutic potency of the vaccine and deterred Treg cell accumulation in the tumor microenvironment. The findings revealed the potential clinical efficacy of combinatorial administration of the GSC‐based vaccine with PD‐L1 blocking therapy. [ABSTRACT FROM AUTHOR]

Background & Aims Treatment with nucleos(t)ide analogues (NA) leads to hepatitis B virus (HBV) DNA suppression in most patients with chronic hepatitis B (CHB), but HBV surface antigen (HBsAg) loss rates are low. Upon NA discontinuation, HBV DNA can return rapidly with ensuing alanine aminotransferase flares and induction of cytokines. Several studies reported higher HBsAg loss rates after stopping therapy, but at present it is unclear if cell-mediated immune responses are altered after treatment discontinuation. The aim of this study was to characterise T cell responses during the early phase of virological relapse, following discontinuation of NA therapy in HBeAg-negative patients. Methods A total of 15 HBeAg-negative patients with CHB on long-term NA treatment were included in a prospective study and subjected to structured NA discontinuation. T cell responses were studied at the end of NA therapy and 4, 8 and 12 weeks thereafter. Results The T cell phenotype of patients with CHB on long-term NA therapy was markedly different compared to healthy individuals, but was only slightly altered after discontinuation of therapy. T cells from patients with HBsAg loss expressed low levels of KLRG1 and PD-1 at all time-points and high levels of Ki-67 and CD38 at week 12 after treatment cessation. In vitro peptide stimulated HBV-specific T cell responses were increased in several patients after NA cessation. Blocking of PD-L1 further enhanced HBV-specific T cell responses, especially after discontinuation of therapy. Conclusion Relapse of active HBV replication after stopping therapy may trigger an immunological environment that enhances the responsiveness of HBV-specific T cells in vitro . Together with other immune interventions, this approach might be of interest for the development of novel therapeutic options to induce HBsAg loss in CHB. Lay summary Relapse of hepatitis B virus replication after discontinuation of nucleos(t)ide analogue therapy in certain patients with chronic hepatitis B may alter the phenotype of T cells and enhance the responsiveness of hepatitis B virus-specific T cells to in vitro peptide stimulation. Blocking PD-L1 can further augment these hepatitis B virus-specific T cell responses. Interestingly, T cells of patients that subsequently achieve hepatitis B surface antigen loss are less exhausted at all time-points after stopping treatment and display a higher proliferative capacity 12-weeks after treatment discontinuation. These findings contribute to the understanding of the immunological events that occur during discontinuation of nucleos(t)ide analogue therapy. [ABSTRACT FROM AUTHOR]

We have recently described a novel therapeutic antibody product (IL2-F8-TNFmut), featuring the simultaneous fusion of murine IL2 and of a TNF mutant with scFv(F8), an antibody specific to the alternatively-spliced extra domain A of fibronectin (EDA). Here, we report on the in vivo characterization of the anti-cancer activity of IL2-F8-TNFmut in four immunocompetent murine models of cancer, CT26, WEHI-164, F9 teratocarcinoma and Lewis lung carcinoma (LLC), using the product alone or in combination with a monoclonal antibody specific to murine PD-L1. All four models exhibited a strong expression of EDA-fibronectin, which was confined to vascular structures for F9 tumors, while the other three malignancies exhibited a more stromal pattern of staining. A complete and long-lasting tumor eradication of CT26 and WEHI-164 tumors was observed in BALB/c mice when IL2-F8-TNFmut was used in combination with PD-L1 blockade. The combination treatment led to improved tumor growth inhibition in 129/SvEv mice bearing murine teratocarcinoma or in C57BL/6 mice bearing murine LLC, but those cancer cures were difficult to achieve in those models. A microscopic analysis of tumor sections, obtained 24 h after pharmacological treatment, revealed that the PD-L1 antibody had homogenously reached tumor cells in vivo and that the combination of PD-L1 blockade with IL2-F8-TNFmut stimulated an influx of NK cells and of T cells into the neoplastic mass. These data indicate that potency-matched dual-cytokine fusion proteins may be ideally suited to potentiate the therapeutic activity of immune check-point inhibitors. [ABSTRACT FROM AUTHOR]

Immunological checkpoint blockade therapies benefit a limited population of cancer patients. We have previously shown that vaccine immunotherapy with Toll‐like receptor (TLR)3‐adjuvant and tumor antigen overcomes anti‐programmed death ligand‐1 (PD‐L1) resistance in mouse tumor models. In the present study, 4 different ovalbumin (OVA)‐expressing tumor cell lines were implanted into syngeneic mice and subjected to anti‐tumor immunotherapy using ARNAX and whole OVA protein. ARNAX is a TLR3‐specific agonist that does not activate the mitochondrial antiviral‐signaling protein (MAVS) pathway, and thus does not induce systemic inflammation. Dendritic cell priming and proliferative CTL were induced by ARNAX + OVA, but complete remission was achieved only in a PD‐L1‐low cell line of EG7. Addition of anti‐PD‐L1 antibody to the ARNAX + OVA therapy brought complete remission to another PD‐L1‐high subline of EG7. Tumor shrinkage but not remission was observed in MO5 in that regimen. We analyzed tumor cells and tumor‐infiltrating immune cells to identify factors associated with successful ARNAX vaccine therapy. Tumors that responded to ARNAX therapy expressed high levels of MHC class I and low levels of PD‐L1. The tumor‐infiltrating immune cells in ARNAX‐susceptible tumors contained fewer immunosuppressive myeloid cells with low PD‐L1 expression. Combination with anti‐PD‐L1 antibody functioned not only within tumor sites but also within lymphoid tissues, augmenting the therapeutic efficacy of the ARNAX vaccine. Notably, ARNAX therapy induced memory CD8+ T cells and rejection of reimplanted tumors. Thus, ARNAX vaccine + anti‐PD‐L1 therapy enabled permanent remission against some tumors that stably present antigens. [ABSTRACT FROM AUTHOR]

Summary Cancer patients having anti-programmed cell death-1 (PD-1)/PD ligand 1 (L1)-unresponsive tumors may benefit from advanced immunotherapy. Double-stranded RNA triggers dendritic cell (DC) maturation to cross-prime antigen-specific cytotoxic T lymphocytes (CTLs) via Toll-like receptor 3 (TLR3). The TLR3-specific RNA agonist, ARNAX, can induce anti-tumor CTLs without systemic cytokine/interferon (IFN) production. Here, we have developed a safe vaccine adjuvant for cancer that effectively implements anti-PD-L1 therapy. Co-administration of ARNAX with a tumor-associated antigen facilitated tumor regression in mouse models, and in combination with anti-PD-L1 antibody, activated tumor-specific CTLs in lymphoid tissues, enhanced CTL infiltration, and overcame anti-PD-1 resistance without cytokinemia. The TLR3-TICAM-1-interferon regulatory factor (IRF)3-IFN-β axis in DCs exclusively participated in CD8 + T cell cross-priming. ARNAX therapy established Th1 immunity in the tumor microenvironment, upregulating genes involved in DC/T cell/natural killer (NK) cell recruitment and functionality. Human ex vivo studies disclosed that ARNAX+antigen induced antigen-specific CTL priming and proliferation in peripheral blood mononuclear cells (PBMCs), supporting the feasibility of ARNAX for potentiating anti-PD-1/PD-L1 therapy in human vaccine immunotherapy. [ABSTRACT FROM AUTHOR]

Background: Pancreatic cancer is one of the most aggressive and intractable malignant tumors, and most deaths from pancreatic cancer are related to metastases. It has been demonstrated in vitro that overexpression of programmed death-ligand 1 (PD-L1) correlates with a lack of phosphatase and tensin homologue (PTEN) expression in pancreatic cancer tissue. This loss of PTEN expression may aberrantly activate the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway, and thereby promote tumor cell survival, proliferation, and disease progression. In this study, we investigated the potential therapeutic effect of blockading PD-L1 expression on the progression of pancreatic cancer and its spontaneous liver metastases in vivo by inhibiting the PI3K/Akt/mTOR signaling pathway. Methods: We investigated the effect of blockading PD-L1 in an orthotopic pancreatic cancer mouse model. The pancreatic tumor weights and inhibition ratios were determined after treatment with antimouse PD-L1 antibody for 5 weeks. We used immunohistochemistry methods to investigate PD-L1 expression in pancreatic cancer tissue and spontaneous liver metastasis tissue. The levels of mRNA and protein expression for various components involved in the PI3K/Akt/mTOR signaling pathway as well as for matrix metalloproteinases-2 and -9 (MMP2 and MMP9) were measured by reverse transcription polymerase chain reaction (RT-PCR) and Western blot methods, respectively. Results: Blockading PD-L1 significantly inhibited tumor growth and decreased the levels of PD-L1 expression in tumor tissue. Furthermore, the levels of PTEN mRNA and protein expression were elevated, while the levels of phospho-Akt (p-Akt) and phospho-mTOR (p-mTOR) protein were decreased in pancreatic cancer and liver metastasis tissues after establishing a PD-L1 blockade. In addition, a PD-L1 blockade decreased the levels of MMP2 and MMP9 mRNA and protein expression in tumor tissues. Conclusion: Our results suggest that a blockade of PD-L1 may inhibit the growth and metastasis of pancreatic cancer by modulating the PI3K/Akt/mTOR pathway. [ABSTRACT FROM AUTHOR]

It is an engaging program for tumor treatment that rationalizes the specific microenvironments, activation of suppressed immune system (immune resistance/escape reversion), and synergistic target therapy. Herein, a biomimetic nanoplatform that combines oxidative stress with genetic immunotherapy to strengthen the therapeutic efficacy is developed. Ru-TePt nanorods, small interfering RNA (PD-L1 siRNA), and biomimetic cellular membrane vesicles with the targeting ability to design a multifunctional Ru-TePt@siRNA-MVs system are rationally integrated. Notably, the Fenton-like activity significantly enhances Ru-TePt nanorods sonosensitization, thus provoking stronger oxidative stress to kill cells directly. Meanwhile, immunogenic cell death is triggered to secrete numerous cytokines and activate T cells. The effective catalase characteristics of Ru-TePt enable the in situ oxygen-producing pump to improve tumor oxygen level and coordinately strengthen the therapeutic effect of SDT followed. More importantly, anti-PD-L1-siRNA mediated immune checkpoint silence of the PD-L1 gene creates an environment conducive to activating cytotoxic T lymphocytes, synergistic with boosted reactive oxygen species-triggered antitumor immune response. The experimental results in vitro and in vivo reveal that the Ru-TePt@siRNA-MVs nanosystems can effectively activate the oxidative stress-triggered immune response and inhibit PD-1/PD-L1 axis-mediated immune resistance. Consequently, this orchestrated treatment paradigm provides valuable insights for developing potential oxidative stress and genetic immunotherapy., (© 2023 Wiley-VCH GmbH.)

Insufficienct T lymphocyte infiltration and unresponsiveness to immune checkpoint blockade therapy are still major difficulties for the clinical treatment of pancreatic ductal adenocarcinoma (PDAC). Although econazole has shown promise in inhibiting PDAC growth, its poor bioavailability and water solubility limit its potential as a clinical therapy for PDAC. Furthermore, the synergistic role of econazole and biliverdin in immune checkpoint blockade therapy in PDAC remains elusive and challenging. Herein, a chemo-phototherapy nanoplatform is designed by which econazole and biliverdin can be co-assembled (defined as FBE NPs), which significantly improve the poor water solubility of econazole and enhance the efficacy of PD-L1 checkpoint blockade therapy against PDAC. Mechanistically, econazole and biliverdin are directly released into the acidic cancer microenvironment, to activate immunogenic cell death via biliverdin-induced PTT/PDT and boost the immunotherapeutic response of PD-L1 blockade. In addition, econazole simultaneously enhances PD-L1 expression to sensitize anti-PD-L1 therapy, leading to suppression of distant tumors, long-term immune memory effects, improved dendritic cell maturation, and tumor infiltration of CD8 + T lymphocytes. The combined FBE NPs and α-PDL1 show synergistic antitumor efficacy. Collectively, FBE NPs show excellent biosafety and antitumor efficacy by combining chemo-phototherapy with PD-L1 blockade, which has promising potential in a precision medicine approach as a PDAC treatment strategy., (© 2023 Wiley-VCH GmbH.)

Although cancer immunotherapy based on immune checkpoint blockade has shown promising clinical responses, the limited host response rate and systemic side effects still restrict immunotherapy efficacy. To address these challenges, here, we construct an aptamer-functionalized metal-organic framework (MOF) catalyst for bioorthogonal activation of Toll-like receptors (TLR) 7 agonists and programmed death-ligand 1 (PDL1) blockade for enhanced antitumor immunotherapy. The catalyst contains ultrasmall Pd nanoparticles enabling the local activation of TLR7 agonists in native form, which results in the remodeling of the tumor microenvironment (TME). Meanwhile, the loaded PDL1 aptamers release in response to phosphate and block the PD1/PDL1 signaling pathway between T cells and cancer cells. Thus, synergy between TLR7 agonists and PDL1 blockade induces the infiltration and activation of immune cells to initiate a robust immune response, thereby simultaneously inhibiting primary and distant metastatic tumors. The immunotherapeutic effect of our design has been demonstrated in both single and bilateral subcutaneous colorectal cancer (CT26) models. In situ bioorthogonal activation of agonists may offer an alternative approach to improve the therapeutic efficacy of immunotherapy with minimized systemic toxicity. Our work will provide good inspiration for current checkpoint blockade-based immunotherapy.

Despite the demonstrated immense potential of immune checkpoint inhibitors in various types of cancers, only a minority of patients respond to these therapies. Immunocytokines designed to deliver an immune-activating cytokine directly to the immunosuppressive tumor microenvironment (TME) and block the immune checkpoint simultaneously may provide a strategic advantage over the combination of two single agents. To increase the response rate to checkpoint blockade, in this study, we developed a novel immunocytokine (LH01) composed of the antibody against programmed death-ligand 1 (PD-L1) fused to interleukin (IL)-15 receptor alpha-sushi domain/IL-15 complex. We demonstrate that LH01 efficiently binds mouse or human PD-L1 and maintains IL-15 stimulatory activity. In syngeneic mouse models, LH01 showed improved antitumor efficacy and safety versus anti-PD-L1 plus LH02 (Fc-sushi-IL15) combination and overcame resistance to anti-PD-L1 treatment. Mechanistically, the dual anti-immunosuppressive function of LH01 activated both the innate and adaptive immune responses and induced a favorable and immunostimulatory TME. Furthermore, combination therapy with LH01 and bevacizumab exerts synergistic antitumor effects in an HT29 colorectal xenograft model. Collectively, our results provide supporting evidence that fusion of anti-PD-L1 and IL-15 might be a potent strategy to treat patients with cold tumors or resistance to checkpoint blockade., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022. Published by Elsevier Inc.)

The use of immune checkpoint inhibitors to treat cancer resulted in unprecedented and durable clinical benefits. However, the response rate among patients remains rather modest. Previous work from our laboratory demonstrated the efficacy of using attenuated bacteria as immunomodulatory anti-cancer agents. The current study investigated the potential of utilizing a low dose of attenuated Salmonella typhimurium to enhance the efficacy of PD-L1 blockade in a relatively immunogenic model of colon cancer. The response of MC38 tumors to treatment with αPD-L1 monoclonal antibody (mAb) was variable, with only 30% of the mice being responsive. Combined treatment with αPD-L1 mAb and Salmonella resulted in 75% inhibition of tumor growth in 100% of animals. Mechanistically, the enhanced response correlated with a decrease in the percentage of tumor-associated granulocytic cells, upregulation in MHC class II expression by intratumoral monocytes and an increase in tumor infiltration by effector T cells. Collectively, these alterations resulted in improved anti-tumor effector responses and increased apoptosis within the tumor. Thus, our study demonstrates that a novel combination treatment utilizing attenuated Salmonella and αPD-L1 mAb could improve the outcome of immunotherapy in colorectal cancer., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Al-Saafeen, Al-Sbiei, Bashir, Mohamed, Masad, Fernandez-Cabezudo and al-Ramadi.)

Checkpoint inhibitors, such as antibodies blocking the PD-1/PD-L1 pathway, are among the most promising immunotherapies to treat metastatic cancers, but their response rate remains low. In addition, the usage of monoclonal antibodies as checkpoint inhibitors is associated with a series of drawbacks. Herein, an all synthetic nanoparticle with PD-L1 blockade capability is developed for cancer photothermal-immunotherapy. The polymeric nanoparticle integrates photothermal treatment, antitumor vaccination, and PD-1/PD-L1 blockade in a single system to augment the antitumor efficacy. In a CT26 bilateral tumor model, intravenously injected nanoparticles accumulate in tumor sites and mediate strong photothermal effects, eradicate the NIR treated primary tumors and elicit strong antitumor immunity by inducing immunogenic cell death (ICD). Growth of the untreated distant tumors is also suppressed due to the synergies of systemic antitumor immune activation and PD-L1 blockade. Our strategy offers a simple but promising approach for the treatment of metastatic cancer. [Display omitted] [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the deadliest primary brain tumor and is generally resistant to immunotherapy because of severe dysfunction of T cells. Novel treatment options are critically needed to overcome the immunotherapy resistance of GBM. Here we demonstrate that Zika virus (ZIKV) treatment improves the efficacy of anti-PD ligand 1 (PD-L1) immunotherapy in GBM. We found that ZIKV induces a strong pro-inflammatory response and increases CD4 + and CD8 + T cell intratumoral infiltration and activation in GBM mouse models. ZIKV treatment of mice bearing GBM tumors inhibits tumor growth and prolongs survival. These therapeutic effects of ZIKV on GBM tumors are negated in mice depleted of T cells. Moreover, ZIKV dramatically promotes activation of the type I interferon signaling pathway in GBM cells. ZIKV treatment potently sensitizes GBM to PD-L1 blockade and provides significant and durable survival benefits. Our findings reveal that ZIKV overcomes the resistance of GBM to immune checkpoint blockade, which may lead to therapeutic applications of ZIKV in individuals with GBM receiving immunotherapy., Competing Interests: The authors declare no competing interests., (© 2022 The Author(s).)