Immune checkpoint blockade: a common denominator approach to cancer therapy

The critical role of tumor microbiome in cancer immunotherapy

In recent years, the microbiome has shown an integral role in cancer immunotherapy and has become a prominent and widely studied topic. A full understanding of the interactions between the tumor microbiome and various immunotherapies offers opportunities for immunotherapy of cancer. This review scrutinizes the composition of the tumor microbiome, the mechanism of microbial immune regulation, the influence of tumor microorganisms on tumor metastasis, and the interaction between tumor microorganisms and immunotherapy. In addition, this review also summarizes the challenges and opportunities of immunotherapy through tumor microbes, as well as the prospects and directions for future related research. In conclusion, the potential of microbial immunotherapy to enhance treatment outcomes for cancer patients should not be underestimated. Through this review, it is hoped that more research on tumor microbial immunotherapy will be done to better solve the treatment problems of cancer patients.

A landscape of checkpoint blockade resistance in cancer: underlying mechanisms and current strategies to overcome resistance

The discovery of immune checkpoints and the development of immune checkpoint inhibitors (ICI) have achieved a durable response in advanced-stage cancer patients. However, there is still a high proportion of patients who do not benefit from ICI therapy due to a lack of response when first treated (primary resistance) or detection of disease progression months after objective response is observed (acquired resistance). Here, we review the current FDA-approved ICI for the treatment of certain solid malignancies, evaluate the contrasting responses to checkpoint blockade in different cancer types, explore the known mechanisms associated with checkpoint blockade resistance (CBR), and assess current strategies in the field that seek to overcome these mechanisms. In order to improve current therapies and develop new ones, the immunotherapy field still has an unmet need in identifying other molecules that act as immune checkpoints, and uncovering other mechanisms that promote CBR.

PD-1/PD-L1 axis: implications in immune regulation, cancer progression, and translational applications

The PD-1/PD-L1 axis is a complex signaling pathway that has an important role in the immune system cells. Programmed cell death protein 1 (PD-1) acts as an immune checkpoint on the T lymphocytes, B lymphocytes, natural killer (NK), macrophages, dendritic cells (DCs), monocytes, and myeloid cells. Its ligand, the programmed cell death 1 ligand (PD-L1), is expressed in the surface of the antigen-presenting cells (APCs). The binding of both promotes the downregulation of the T cell response to ensure the activation to prevent the onset of chronic immune inflammation. This axis in the tumor microenvironment (TME) performs a crucial role in the tumor progression and the escape of the tumor by neutralizing the immune system, the engagement of PD-L1 with PD-1 in the T cell causes dysfunctions, neutralization, and exhaustion, providing the tumor mass production. This review will provide a comprehensive overview of the functions of the PD-1/PD-L1 system in immune function, cancer, and the potential therapeutic implications of the PD-1/PD-L1 pathway for cancer management.

Comprehensive pan‑cancer analysis of MTDH for human tumor prognosis and as an immunological biomarker including breast and kidney cancer

Metadherin (MTDH), initially discovered in primary astrocytes of the human fetus through rapid subtraction hybridization and labeled as astrocyte elevated gene-1, represents a widely recognized oncogene present in multiple types of cancers. However, the role of MTDH in different types of cancer remains unclear. To address this, a comprehensive analysis of MTDH across various types of cancers was conducted by utilizing multiple databases such as The Cancer Genome Atlas. The present analysis discovered that MTDH exhibits differential expression in different types of cancer and is associated with important factors including tumor mutational burden and microsatellite instability. These findings highlighted the significance of MTDH in the tumor microenvironment and its involvement in the development of immune cells in specific cancers. Furthermore, the results of the present study indicated that the expression of MTDH is strongly correlated with clinical prognosis, mutations and immune cell infiltration. MTDH could serve as a potential indicator of patient prognosis and potentially play a role in modulating the immune system. Given its potential as a novel immunological checkpoint, MTDH may be a viable target for tumor immunotherapy.

Subclone from CT26 resistant to anti-PD-1 therapy associated with increased expression of genes related to glucocorticoids

BACKGROUND

Although the use of anti-PD-1 antibodies has fundamentally changed traditional cancer treatment, most patients are resistant to anti-PD-1 treatment. Glucocorticoids (GCs) play an important role in tumorigenesis and tumor progression, but the role of endogenous GCs in resistance to anti-PD-1 antibody therapy remains unclear.

METHODS

Single cell-derived cell lines (SCDCLs) were generated from a colorectal cancer cell line (CT26) using limiting dilution. We analyzed tumor tissues from anti-PD-1 antibody-treated and untreated mice inoculated with SCDCLs via transcriptome sequencing and flow cytometry to detect pathway activity and immune cell composition changes in the tumor microenvironment.

RESULTS

Five SCDCLs were inoculated into wild-type BALB/c mice (all tumorigenic). Single-cell clone (SCC)-2 exhibited the slowest growth rates both in vivo and in vitro compared to other single-cell clones, and better long-term survival than SCC1 and CT26. Flow cytometry showed that SCC2 tumor-bearing mice exhibited significantly higher infiltration of T cells within the tumor tissue, and higher expression of PD-1 on these T cells than the other groups in vivo. However, the SCC2 group showed no response to anti-PD-1 therapy. Transcriptome analysis revealed that the SCC2 group exhibited increased expression of genes related to GC (Hsd11b1, Sgk3, Tgfbr2, and Il7r) compared to SCC2-anti-PD-1 treated tumors.

CONCLUSIONS

GC pathway activation is related to resistance to anti-PD-1 therapy.

Microecological regulation in HCC therapy: Gut microbiome enhances ICI treatment

The exploration of the complex mechanisms of cancer immunotherapy is rapidly evolving worldwide, and our focus is on the interaction of hepatocellular carcinoma (HCC) with immune checkpoint inhibitors (ICIs), particularly as it relates to the regulatory role of the gut microbiome. An important basis for the induction of immune responses in HCC is the presence of specific anti-tumor cells that can be activated and reinforced by ICIs, which is why the application of ICIs results in sustained tumor response rates in the majority of HCC patients. However, mechanisms of acquired resistance to immunotherapy in unresectable HCC result in no long-term benefit for some patients. The significant heterogeneity of inter-individual differences in the gut microbiome in response to treatment with ICIs makes it possible to target modulation of specific gut microbes to assist in augmenting checkpoint blockade therapies in HCC. This review focuses on the complex relationship between the gut microbiome, host immunity, and HCC, and emphasizes that manipulating the gut microbiome to improve response rates to cancer ICI therapy is a clinical strategy with unlimited potential.

Colorectal medullary carcinoma: a pathological subtype with intense immune response and potential to benefit from immune checkpoint inhibitors

INTRODUCTION

Different pathological types of colorectal cancer have distinguished immune landscape, and the efficacy of immunotherapy will be completely different. Colorectal medullary carcinoma, accounting for 2.2-3.2%, is characterized by massive lymphocyte infiltration. However, the attention to the immune characteristics of colorectal medullary carcinoma is insufficient.

AREA COVERED

We searched the literature about colorectal medullary carcinoma on PubMed through November 2023to investigate the hallmarks of colorectal medullary carcinoma's immune landscape, compare medullary carcinoma originating from different organs and provide theoretical evidence for precise treatment, including applying immunotherapy and BRAF inhibitors.

EXPERT OPINION

Colorectal medullary carcinoma is a pathological subtype with intense immune response, with six immune characteristics and has the potential to benefit from immunotherapy. Mismatch repair deficiency, ARID1A missing and BRAF V600E mutation often occurs. IFN-γ pathway is activated and PD-L1 expression is increased. Abundant lymphocyte infiltration performs tumor killing function. In addition, BRAF mutation plays an important role in the occurrence and development, and we can consider the combination of BRAF inhibitors and immunotherapy in patients with BRAF mutant. The exploration of colorectal medullary carcinoma will arouse researchers' attention to the correlation between pathological subtypes and immune response, and promote the process of precise immunotherapy.

Advances and clinical applications of immune checkpoint inhibitors in hematological malignancies

Immune checkpoints are differentially expressed on various immune cells to regulate immune responses in tumor microenvironment. Tumor cells can activate the immune checkpoint pathway to establish an immunosuppressive tumor microenvironment and inhibit the anti-tumor immune response, which may lead to tumor progression by evading immune surveillance. Interrupting co-inhibitory signaling pathways with immune checkpoint inhibitors (ICIs) could reinvigorate the anti-tumor immune response and promote immune-mediated eradication of tumor cells. As a milestone in tumor treatment, ICIs have been firstly used in solid tumors and subsequently expanded to hematological malignancies, which are in their infancy. Currently, immune checkpoints have been investigated as promising biomarkers and therapeutic targets in hematological malignancies, and novel immune checkpoints, such as signal regulatory protein α (SIRPα) and tumor necrosis factor-alpha-inducible protein 8-like 2 (TIPE2), are constantly being discovered. Numerous ICIs have received clinical approval for clinical application in the treatment of hematological malignancies, especially when used in combination with other strategies, including oncolytic viruses (OVs), neoantigen vaccines, bispecific antibodies (bsAb), bio-nanomaterials, tumor vaccines, and cytokine-induced killer (CIK) cells. Moreover, the proportion of individuals with hematological malignancies benefiting from ICIs remains lower than expected due to multiple mechanisms of drug resistance and immune-related adverse events (irAEs). Close monitoring and appropriate intervention are needed to mitigate irAEs while using ICIs. This review provided a comprehensive overview of immune checkpoints on different immune cells, the latest advances of ICIs and highlighted the clinical applications of immune checkpoints in hematological malignancies, including biomarkers, targets, combination of ICIs with other therapies, mechanisms of resistance to ICIs, and irAEs, which can provide novel insight into the future exploration of ICIs in tumor treatment.

Dual blockade immunotherapy targeting PD-1/PD-L1 and CTLA-4 in lung cancer

Cancer immunotherapies, represented by immune checkpoint inhibitors (ICIs), have reshaped the treatment paradigm for both advanced non-small cell lung cancer and small cell lung cancer. Programmed death receptor-1/programmed death receptor ligand-1 (PD-1/PD-L1) and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) are some of the most common and promising targets in ICIs. Compared to ICI monotherapy, which occasionally demonstrates treatment resistance and limited efficacy, the dual blockade immunotherapy targeting PD-1/PD-L1 and CTLA-4 operates at different stages of T cell activation with synergistically enhancing immune responses against cancer cells. This emerging dual therapy heralds a new direction for cancer immunotherapy, which, however, may increase the risk of drug-related adverse reactions while improving efficacy. Previous clinical trials have explored combination therapy strategy of anti-PD-1/PD-L1 and anti-CTLA-4 agents in lung cancer, yet its efficacy remains to be unclear with the inevitable incidence of immune-related adverse events. The recent advent of bispecific antibodies has made this sort of dual targeting more feasible, aiming to alleviate toxicity without compromising efficacy. Thus, this review highlights the role of dual blockade immunotherapy targeting PD-1/PD-L1 and CTLA-4 in treating lung cancer, and further elucidates its pre-clinical mechanisms and current advancements in clinical trials. Besides, we also provide novel insights into the potential combinations of dual blockade therapies with other strategies to optimize the future treatment mode for lung cancer.

Novel insights into the regulation of exosomal PD-L1 in cancer: From generation to clinical application

Programmed cell death ligand 1 (PD-L1) interacts with programmed cell death 1 (PD-1), leading to T cell exhaustion and promoting tumor cell survival, ultimately mediating immunosuppression. While FDA-approved monoclonal antibodies targeting the PD-1/PD-L1 interaction have shown success in cancer treatment, some patients experience limited and short-lived therapeutic outcomes. Recent studies have identified PD-L1 expression not only on tumor cell surfaces but also on exosomes, with secretion pathways including both conventional and unconventional endocytosis routes, presenting a unique therapeutic opportunity. Emerging evidence suggests that exosomal PD-L1 contributes to systemic immunosuppression, potentially counteracting the effects of anti-PD-1 checkpoint therapies. However, the significance of exosomal PD-L1 in clinical cancer patients unresponsive to anti-PD-1/PD-L1 immunotherapy, as well as the factors regulating its generation, remain unclear. Moreover, the mechanisms underlying PD-L1 expression on exosomes and its regulation in cancer are yet to be fully elucidated. This review primarily focuses on the mechanisms modulating exosomal PD-L1 generation in cancer, while also outlining its involvement in immunosuppression, tumor proliferation, and response to cancer immunotherapy. Additionally, we explore the potential of exosomal PD-L1 as a cancer biomarker and therapeutic target, aiming to provide a comprehensive overview of this emerging field and its implications for cancer treatment and diagnosis.

Novel insights into immune cells modulation of tumor resistance

Tumor resistance poses a significant challenge to effective cancer treatment, making it imperative to explore new therapeutic strategies. Recent studies have highlighted the profound involvement of immune cells in the development of tumor resistance. Within the tumor microenvironment, macrophages undergo polarization into the M2 phenotype, thus promoting the emergence of drug-resistant tumors. Neutrophils contribute to tumor resistance by forming extracellular traps. While T cells and natural killer (NK) cells exert their impact through direct cytotoxicity against tumor cells. Additionally, dendritic cells (DCs) have been implicated in preventing tumor drug resistance by stimulating T cell activation. In this review, we provide a comprehensive summary of the current knowledge regarding immune cell-mediated modulation of tumor resistance at the molecular level, with a particular focus on macrophages, neutrophils, DCs, T cells, and NK cells. The targeting of immune cell modulation exhibits considerable potential for addressing drug resistance, and an in-depth understanding of the molecular interactions between immune cells and tumor cells holds promise for the development of innovative therapies. Furthermore, we explore the clinical implications of these immune cells in the treatment of drug-resistant tumors. This review emphasizes the exploration of novel approaches that harness the functional capabilities of immune cells to effectively overcome drug-resistant tumors.

Neuromedin U receptor 1 deletion leads to impaired immunotherapy response and high malignancy in colorectal cancer

Colorectal cancer (CRC) exhibits significant heterogeneity, impacting immunotherapy efficacy, particularly in immune desert subtypes. Neuromedin U receptor 1 (NMUR1) has been reported to perform a vital function in immunity and inflammation. Through comprehensive multi-omics analyses, we have systematically characterized NMUR1 across various tumors, assessing expression patterns, genetic alterations, prognostic significance, immune infiltration, and pathway associations at both the bulk sequencing and single-cell scales. Our findings demonstrate a positive correlation between NMUR1 and CD8+ T cell infiltration, with elevated NMUR1 levels in CD8+ T cells linked to improved immunotherapy outcomes in patients with CRC. Further, we have validated the NMUR1 expression signature in CRC cell lines and patient-derived tissues, revealing its interaction with key immune checkpoints, including lymphocyte activation gene 3 and cytotoxic T-lymphocyte-associated protein 4. Additionally, NMUR1 suppression enhances CRC cell proliferation and invasiveness. Our integrated analyses and experiments open new avenues for personalized immunotherapy strategies in CRC treatment.

PD-1/LAG-3 co-signaling profiling uncovers CBL ubiquitin ligases as key immunotherapy targets

Many cancer patients do not benefit from PD-L1/PD-1 blockade immunotherapies. PD-1 and LAG-3 co-upregulation in T-cells is one of the major mechanisms of resistance by establishing a highly dysfunctional state in T-cells. To identify shared features associated to PD-1/LAG-3 dysfunctionality in human cancers and T-cells, multiomic expression profiles were obtained for all TCGA cancers immune infiltrates. A PD-1/LAG-3 dysfunctional signature was found which regulated immune, metabolic, genetic, and epigenetic pathways, but especially a reinforced negative regulation of the TCR signalosome. These results were validated in T-cell lines with constitutively active PD-1, LAG-3 pathways and their combination. A differential analysis of the proteome of PD-1/LAG-3 T-cells showed a specific enrichment in ubiquitin ligases participating in E3 ubiquitination pathways. PD-1/LAG-3 co-blockade inhibited CBL-B expression, while the use of a bispecific drug in clinical development also repressed C-CBL expression, which reverted T-cell dysfunctionality in lung cancer patients resistant to PD-L1/PD-1 blockade. The combination of CBL-B-specific small molecule inhibitors with anti-PD-1/anti-LAG-3 immunotherapies demonstrated notable therapeutic efficacy in models of lung cancer refractory to immunotherapies, overcoming PD-1/LAG-3 mediated resistance.

Aptamer-assisted phage display: enhancing checkpoint inhibition with a peptide and an aptamer targeting distinct sites on a single PD-L1 protein

Utilizing a novel approach known as aptamer-assisted phage display (APD), we identified an anti-PD-L1 peptide, NV Pep, capable of simultaneous binding to PD-L1 alongside the DNA aptamer MJ5C. Combined inhibition using NV Pep and MJ5C demonstrated significant enhancement compared to individual ligands against the PD-1/PD-L1 interaction.

Unlocking immunotherapy targets: programmed death 1 and its ligand and their correlation with tumour grade in feline injection site sarcoma

In this study, the immunohistochemical expression of programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1), which could facilitate a novel approach to immunotherapy for feline injection site sarcomas (FISSs), was investigated. Treatment strategies based on the suppression of this pathway are possible for tumours expressing PD-1/PD-L1. In this context, FISSs were histologically classified, the grade of sarcoma and the intensity of lymphocyte infiltration determined and PD-1 and PD-L1 expression evaluated in tumours of different grade. Tumours were immunolabelled for vimentin, S100, smooth muscle actin and sarcomeric actin. Fibrosarcoma was diagnosed in eight cases, undifferentiated sarcoma in one case, liposarcoma in one case and rhabdomyosarcoma in one case. PD-1 expression was found mainly in lymphoid infiltrations and macrophage-like cells, while PD-L1 was found primarily in tumour cells and infiltrated macrophage-like cells. By Pearson correlation analysis, tumour differentiation was found to have a moderate correlation with PD-1 (P <0.05) and a high correlation with PD-L1 (P <0.01). Tumour grade had a low correlation with PD-1 and a moderate correlation with PD-L1 (P >0.05). A moderate correlation was also detected between PD-1 and PD-L1 (P <0.05). It was concluded that the increased expression of PD-1 and PD-L1 may be associated with poor tumour differentiation and, therefore, poor prognosis in FISS.

ACT001 inhibits primary central nervous system lymphoma tumor growth by enhancing the anti-tumor effect of T cells

Primary central nervous system lymphoma (PCNSL) is a group of malignant brain tumors with a poor prognosis, and new therapeutic approaches for this tumor urgently need to be investigated. Formulated from a long-standing anti-inflammatory drugs, ACT001 has demonstrated in clinical research to be able to pass through the blood-brain barrier (BBB) and affect the central nervous system. The effects of ACT001 on PCNSL cell apoptosis, proliferation and immune-related indexes were detected by flow cytometry, and the efficacy of ACT001 was verified in vivo by constructing a mouse PCNSL tumor model. ACT001 significantly inhibited PCNSL cell proliferation and induced apoptosis in vitro. In addition, ACT001 can significantly inhibit the PD-1/PD-L1 expression and restore the function of T cells, so that the immune system cannot allow tumor cells to escape. In vivo experiments show that co-infusion of ACT001 and T cells effectively inhibits PCNSL tumor growth in NSG mice. Our work describes the inhibitory effect of ACT001 on the PCNSL cell line and demonstrated the inhibitory effect of ACT001 on immune checkpoints.

Construction of Hierarchically Biomimetic Iron Oxide Nanosystems for Macrophage Repolarization-Promoted Immune Checkpoint Blockade of Cancer Immunotherapy

Cancer immunotherapy is developing as the mainstream strategy for treatment of cancer. However, the interaction between the programmed cell death protein-1 (PD-1) and the programmed death ligand 1 (PD-L1) restricts T cell proliferation, resulting in the immune escape of tumor cells. Recently, immune checkpoint inhibitor therapy has achieved clinical success in tumor treatment through blocking the PD-1/PD-L1 checkpoint pathway. However, the presence of M2 tumor-associated macrophages (TAMs) in the tumor microenvironment (TME) will inhibit antitumor immune responses and facilitate tumor growth, which can weaken the effectiveness of immune checkpoint inhibitor therapy. The repolarization of M2 TAMs into M1 TAMs can induce the immune response to secrete proinflammatory factors and active T cells to attack tumor cells. Herein, hollow iron oxide (Fe3O4) nanoparticles (NPs) were prepared for reprogramming M2 TAMs into M1 TAMs. BMS-202, a small-molecule PD-1/PD-L1 inhibitor that has a lower price, higher stability, lower immunogenicity, and higher tumor penetration ability compared with antibodies, was loaded together with pH-sensitive NaHCO3 inside hollow Fe3O4 NPs, followed by wrapping with macrophage membranes. The formed biomimetic FBN@M could produce gaseous carbon dioxide (CO2) from NaHCO3 in response to the acidic TME, breaking up the macrophage membranes to release BMS-202. A series of in vitro and in vivo assessments revealed that FBN@M could reprogram M2 TAMs into M1 TAMs and block the PD-1/PD-L1 pathway, which eventually induced T cell activation and the secretion of TNF-α and IFN-γ to kill the tumor cells. FBN@M has shown a significant immunotherapeutic efficacy for tumor treatment.

Light-activated azobenzene peptide inhibitor of the PD-1/PD-L1 interaction

Inhibiting the PD-1/PD-L1 protein-protein interaction is a key immunotherapy for cancer. Antibodies dominate the clinical space but are costly, with limited applicability and immune side effects. We developed a photo-controlled azobenzene peptide that selectively inhibits the PD-1/PD-L1 interaction when in the cis isomer only. Activity is demonstrated in in vitro and cellular assays.

Canopy FGF signaling regulator 3 affects prognosis, immune infiltration, and PI3K/AKT pathway in colon adenocarcinoma

BACKGROUND

Colon adenocarcinoma (COAD) is a malignant tumor of the digestive system. The mechanisms underlying COAD development and progression are still largely unknown.

AIM

To identify the role of canopy FGF signaling regulator 3 (CNPY3) in the development and progression of COAD by using bioinformatic tools and functional experiments.

METHODS

Bioinformatic data were downloaded from public databases. The associations of clinicopathological features, survival, and immune function with the expression of CNPY3 were analyzed. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses and Gene Set Enrichment Analysis were used to explore the related pathways. Then, quantitative real-time PCR and immunohistochemistry were used for validation of CNPY3 expression in clinical samples and tumor cell lines. Cell lines with CNPY3 knockdown were constructed to further analyze gene functions. The functional experiments included proliferation, invasion, migration and apoptosis assays.

RESULTS

In both the TCGA cohort and the merged dataset, elevated CNPY3 expression was observed in tumor tissues. High CNPY3 expression correlated with adverse survival and compromised immune functions. Functional enrichment analysis suggested that the pro-oncogenic properties of CNPY3 might be linked to the PI3K-AKT signaling pathway. CNPY3 expression was validated at both the RNA and protein levels. Functional assays indicated that cell proliferation, invasion, and migration were inhibited and cell apoptosis was promoted after CNPY3 knockdown. Additionally, Western blot results revealed the downregulation of key proteins in the PI3K/AKT pathway following CNPY3 knockdown. PI3K/AKT pathway activator reversed the decrease in proliferation, invasion, and migration and the increase in apoptosis. Notably, CNPY3 knockdown still affected the cells when the pathway was inhibited.

CONCLUSION

This study showed that CNPY3 is upregulated in COAD and might regulate COAD development and progression by the PI3K/AKT pathway. Thus, CNPY3 might be a promising therapeutic target.

Risk and survival of patients with non-small cell lung cancer and pre-existing autoimmune disorders receiving immune checkpoint blockade therapy: Survival analysis with inverse probability weighting from a nationwide, multi-institutional, retrospective study (NEJ047)

BACKGROUND

The risk and survival of patients with non-small cell lung cancer (NSCLC) with pre-existing autoimmune disorders (AIDs) receiving immune checkpoint blockade (ICB) therapy have not been clearly established.

PATIENTS AND METHODS

This multi-institutional, retrospective cohort study was conducted in collaboration with 20 centers in Japan.

RESULTS

In total, 229 patients with advanced or recurrent NSCLC and pre-existing AID, with or without ICB treatment from January 2010-February 2020, were included and analyzed. Among 69 patients who received ICB, 2 received two lines of ICBs with a total of 71 ICB treatments; 57 (80.3 %) and 14 (19.7 %) patients received ICB monotherapy and combination therapy, respectively. AID flares were observed in 18 patients (25.4 %, 95 % confidence interval [CI], 15.8-37.1 %) receiving ICB. AID exacerbations were more likely when NSCLC was diagnosed less than 1 year after the AID diagnosis (odds ratio 5.26 [95 % CI, 1.40-21.61]; P = 0.016). Immune-related adverse events were observed in 32 patients (45.1 %, 95 % CI, 33.2-57.3 %); 17 had grade 3 or higher. The safety profile of combination immunotherapy was not significantly different from that of the monotherapy. After inverse probability weighting, the use of ICB prolonged survival (hazard ratio 0.43 [95 % CI, 0.26-0.70]; P = 0.0006).

CONCLUSIONS

These findings revealed a novel risk factor for AID flares following ICB treatment, that is the diagnosis of NSCLC within 1 year of AID diagnosis, and showed that ICBs may improve survival in this population. These results support the utilization of ICB in patients with NSCLC and pre-existing AID.

Release of Exosomal PD-L1 in Bone and Soft Tissue Sarcomas and Its Relationship to Radiotherapy

(1) Background: Exosomal PD-L1 has garnered attention owing to its role in instigating systemic immune suppression. The objective of this study is to elucidate whether bone and soft tissue sarcoma cells possess the capacity to secrete functionally active exosomal PD-L1 and whether radiotherapy (RT) induces the exosomal PD-L1 release. (2) Methods: Human osteosarcoma cell line 143B and human fibrosarcoma cell line HT1080 were utilized. Exosomes were isolated from the culture medium and blood via ultracentrifugation. The expression of PD-L1 on both tumor cells and exosomes was evaluated. The inhibitory effect on PBMC was employed to assess the activity of exosomal PD-L1. Post radiotherapy, changes in PD-L1 expression were compared. (3) Results: Exosomal PD-L1 was detected in the culture medium of tumor cells but was absent in the culture medium of PD-L1 knockout cells. Exosomal PD-L1 exhibited an inhibitory effect on PBMC activation. In tumor-bearing mice, human-derived exosomal PD-L1 was detected in the bloodstream. Following radiotherapy, tumor cells upregulated PD-L1, and human-derived exosomal PD-L1 were detected in the bloodstream. (4) Conclusions: Exosomal PD-L1 emanates from bone and soft tissue sarcoma cells and is disseminated into the circulatory system. The levels of PD-L1 in tumor cells and the release of exosomal PD-L1 were augmented after irradiation with RT.

Differential impact of genetic deletion of TIGIT or PD-1 on melanoma-specific T-lymphocytes

Immune checkpoint (IC) blockade and adoptive transfer of tumor-specific T-cells (ACT) are two major strategies to treat metastatic melanoma. Their combination can potentiate T-cell activation in the suppressive tumor microenvironment, but the autoimmune adverse effects associated with systemic injection of IC blockers persist with this strategy. ACT of tumor-reactive T-cells defective for IC expression would overcome this issue. For this purpose, PD-1 and TIGIT appear to be relevant candidates, because their co-expression on highly tumor-reactive lymphocytes limits their therapeutic efficacy within the tumor microenvironme,nt. Our study compares the consequences of PDCD1 or TIGIT genetic deletion on anti-tumor properties and T-cell fitness of melanoma-specific T lymphocytes. Transcriptomic analyses revealed down-regulation of cell cycle-related genes in PD-1KO T-cells, consistent with biological observations, whereas proliferative pathways were preserved in TIGITKO T-cells. Functional analyses showed that PD-1KO and TIGITKO T-cells displayed superior antitumor reactivity than their wild-type counterpart in vitro and in a preclinical melanoma model using immunodeficient mice. Interestingly, it appears that TIGITKO T-cells were more effective at inhibiting tumor cell proliferation in vivo, and persist longer within tumors than PD-1KO T-cells, consistent with the absence of impact of TIGIT deletion on T-cell fitness. Taken together, these results suggest that TIGIT deletion, over PD-1 deletion, in melanoma-specific T-cells is a compelling option for future immunotherapeutic strategies.

Bifunctional black phosphorus quantum dots platform: Delivery and remarkable immunotherapy enhancement of STING agonist

Cancer immunotherapy has been developed to improve therapeutic effects for patients by activating the innate immune stimulator of interferon gene (STING) pathway. However, most patients cannot benefit from this therapy, mainly due to the problems of excessively low immune responses and lack of tumor specificity. Herein, we report a solution to these two problems by developing a bifunctional platform of black phosphorus quantum dots (BPQDs) for STING agonists. Specifically, BPQDs could connect targeted functional groups and regulate surface zeta potential by coordinating metal ions to increase loading (over 5 times) while maintaining high universality (7 STING agonists). The controlled release of STING agonists enabled specific interactions with their proteins, activating the STING pathway and stimulating the secretion release of immunosuppressive factors by phosphorylating TBK1 and IFN-IRF3 and secreting high levels of immunostimulatory cytokines, including IL-6, IFN-α, and IFN-β. Moreover, the immunotherapy was enhanced was enhanced mild photothermal therapy (PTT) of BPQDs platform, producing enough T cells to eliminate tumors and prevent tumor recurrence. This work facilitates further research on targeted delivery of small-molecule immune drugs to enhance the development of clinical immunotherapy.

High-dimensional mapping of human CEACAM1 expression on immune cells and association with melanoma drug resistance

BACKGROUND

Human carcinoembryonic antigen cell adhesion molecule 1 (CEACAM1) is an inhibitory cell surface protein that functions through homophilic and heterophilic ligand binding. Its expression on immune cells in human tumors is poorly understood.

METHODS

An antibody that distinguishes human CEACAM1 from other highly related CEACAM family members was labeled with 159Tb and inserted into a panel of antibodies that included specificity for programmed cell death protein 1 (PD1) and PD-L1, which are targets of immunotherapy, to gain a data-driven immune cell atlas using cytometry by time-of-flight (CyTOF). A detailed inventory of CEACAM1, PD1, and PD-L1 expression on immune cells in metastatic lesions to lymph node or soft tissues and peripheral blood samples from patients with treatment-naive and -resistant melanoma as well as peripheral blood samples from healthy controls was performed.

RESULTS

CEACAM1 is absent or at low levels on healthy circulating immune cells but is increased on immune cells in peripheral blood and tumors of melanoma patients. The majority of circulating PD1-positive NK cells, innate T cells, B cells, monocytic cells, dendritic cells, and CD4+ T cells in the peripheral circulation of treatment-resistant disease co-express CEACAM1 and are demonstrable as discrete populations. CEACAM1 is present on distinct types of cells that are unique to the tumor microenvironment and exhibit expression levels that are highest in treatment resistance; this includes tumor-infiltrating CD8+ T cells.

CONCLUSIONS

To the best of our knowledge, this work represents the first comprehensive atlas of CEACAM1 expression on immune cells in a human tumor and reveals an important correlation with treatment-resistant disease. These studies suggest that agents targeting CEACAM1 may represent appropriate partners for PD1-related pathway therapies.

Harnessing the capacity of phytochemicals to enhance immune checkpoint inhibitor therapy of cancers: A focus on brain malignancies

Brain cancers, particularly glioblastoma multiforme (GBM), are challenging health issues with frequent unmet aspects. Today, discovering safe and effective therapeutic modalities for brain tumors is among the top research interests. Immunotherapy is an emerging area of investigation in cancer treatment. Since immune checkpoints play fundamental roles in repressing anti-cancer immunity, diverse immune checkpoint inhibitors (ICIs) have been developed, and some monoclonal antibodies have been approved clinically for particular cancers; nevertheless, there are significant concerns regarding their efficacy and safety in brain tumors. Among the various tools to modify the immune checkpoints, phytochemicals show good effectiveness and excellent safety, making them suitable candidates for developing better ICIs. Phytochemicals regulate multiple immunological checkpoint-related signaling pathways in cancer biology; however, their efficacy for clinical cancer immunotherapy remains to be established. Here, we discussed the involvement of immune checkpoints in cancer pathology and summarized recent advancements in applying phytochemicals in modulating immune checkpoints in brain tumors to highlight the state-of-the-art and give constructive prospects for future research.

Therapeutic implications of signaling pathways and tumor microenvironment interactions in esophageal cancer

Esophageal cancer (EC) is significantly influenced by the tumor microenvironment (TME) and altered signaling pathways. Downregulating these pathways in EC is essential for suppressing tumor development, preventing metastasis, and enhancing therapeutic outcomes. This approach can increase tumor sensitivity to treatments, enhance patient outcomes, and inhibit cancer cell proliferation and spread. The TME, comprising cellular and non-cellular elements surrounding the tumor, significantly influences EC's development, course, and treatment responsiveness. Understanding the complex relationships within the TME is crucial for developing successful EC treatments. Immunotherapy is a vital TME treatment for EC. However, the heterogeneity within the TME limits the application of anticancer drugs outside clinical settings. Therefore, identifying reliable microenvironmental biomarkers that can detect therapeutic responses before initiating therapy is crucial. Combining approaches focusing on EC signaling pathways with TME can enhance treatment outcomes. This integrated strategy aims to interfere with essential signaling pathways promoting cancer spread while disrupting factors encouraging tumor development. Unraveling aberrant signaling pathways and TME components can lead to more focused and efficient treatment approaches, identifying specific cellular targets for treatments. Targeting the TME and signaling pathways may reduce metastasis risk by interfering with mechanisms facilitating cancer cell invasion and dissemination. In conclusion, this integrative strategy has significant potential for improving patient outcomes and advancing EC research and therapy. This review discusses the altered signaling pathways and TME in EC, focusing on potential future therapeutics.

A Comparative Study of Antitumor Immunity Induced by Radiofrequency Microwave and Cryoablation in Hepatocellular Carcinoma

PURPOSE

This study aimed to compare the immune responses induced by microwave ablation (MWA), radiofrequency ablation (RFA), and cryoablation (CRYO) in hepatocellular carcinoma (HCC) and identify differences in immune responses and the timing of immune changes.

MATERIALS AND METHODS

A bilateral subcutaneous model was established in C57 mice, and the successfully modeled mice were divided into the microwave (n = 15), radiofrequency (n = 15), CRYO (n = 15), control (n = 9), and blank groups (n = 3). Mice in the control group were dissected before ablation, whereas mice in the three ablation groups underwent ultrasound-guided ablation of one axillary tumor. Three mice were sacrificed and dissected at 1-4 weeks after ablation. After tissue processing, flow cytometry was used to detect the levels of CD8 + T and regulatory T (Treg) cells in the tissue, and western blotting was used to assess the level of programmed cell death ligand 1 (PD-L1) protein in the tumor tissue.

RESULTS

The pattern of immune changes after the three types of ablation was consistent, with immune changes occurring at 3-4 weeks. CRYO induced the most significant increase in the percentage of CD8 + T cells. There were no significant differences in the levels of Treg cells and the level of PD-L1 protein among the three types of ablation (p > 0.05), but the decline in Treg cells and PD-L1 protein level caused by CRYO was the most pronounced.

CONCLUSION

In the HCC mouse model, the immune changes following the three types of ablation were consistent, with immune changes occurring at 3-4 weeks. Among them, CRYO elicited the strongest adaptive immune response, and RFA outperformed MWA.

Intratumoral Injection of Immunotherapeutics: State of the Art and Future Directions

Systemic immunotherapies have led to tremendous progress across the cancer landscape. However, several challenges exist, potentially limiting their efficacy in the treatment of solid tumors. Direct intratumoral injection can increase the therapeutic index of immunotherapies while overcoming many of the barriers associated with systemic administration, including limited bioavailability to tumors and potential systemic safety concerns. However, challenges remain, including the lack of standardized approaches for administration, issues relating to effective drug delivery, logistical hurdles, and safety concerns specific to this mode of administration. This article reviews the biologic rationale for the localized injection of immunotherapeutic agents into tumors. It also addresses the existing limitations and practical considerations for safe and effective implementation and provide recommendations for optimizing logistics and treatment workflows. It also highlights the critical role that radiologists, interventional radiologists, and medical physicists play in intratumoral immunotherapy with respect to target selection, image-guided administration, and response assessment.

PD-L1 at the crossroad between RNA metabolism and immunosuppression

Programmed death ligand-1 (PD-L1) is a key component of tumor immunosuppression. The uneven therapeutic results of PD-L1 therapy have stimulated intensive studies to better understand the mechanisms underlying altered PD-L1 expression in cancer cells, and to determine whether, beyond its immune function, PD-L1 might have intracellular functions promoting tumor progression and resistance to treatments. In this Opinion, we focus on paradigmatic examples highlighting the central role of PD-L1 in post-transcriptional regulation, with PD-L1 being both a target and an effector of molecular mechanisms featured prominently in RNA research, such as RNA methylation, phase separation and RNA G-quadruplex structures, in order to highlight vulnerabilities on which future anti-PD-L1 therapies could be built.

Identification of TNFAIP6 as a reliable prognostic indicator of low-grade glioma

Glioma is the most common primary malignant tumor in the brain, characterizing by high disability rate and high recurrence rate. Although low-grade glioma (LGG) has a relative benign biological behavior, the prognosis of LGG patients still varies greatly. Glioma stem cells (GSCs) are considered as the chief offenders of glioma cell proliferation, invasion and resistance to therapies. Our study screened a series of glioma stem cell-related genes (GSCRG) based on mDNAsi and WCGNA, and finally established a reliable single-gene prognostic model through 101 combinations of 10 machine learning methods. Our result suggested that the expression level of TNFAIP6 is negatively correlated with the prognosis of LGG patients, which may be the result of pro-cancer signaling pathways activation and immunosuppression. In general, this study revealed that TNFAIP6 is a robust and valuable prognostic factor in LGG, and may be a new target for LGG treatment.

Comprehensive pan-cancer analysis reveals that C5orf34 regulates the proliferation and mortality of lung cancer

The gene C5orf34 exhibits evolutionary conservation among mammals, and emerging evidence suggests its potential involvement in tumor development; however, comprehensive investigations of this gene are lacking. This study aims to elucidate the functional attributes and underlying mechanisms of C5orf34 in cancer. To evaluate its clinical predictive value, we conducted an analysis of the pan-cancerous expression, clinical data, mutation, and methylation data of C5orf34. Additionally, we investigated the correlation between C5orf34 and tumor mutant load (TMB), immune cell infiltration, and microsatellite instability (MSI) through relevant analyses. Furthermore, immunohistochemical (IHC) staining was employed to validate clinical samples, while knockdown and overexpression experiments and transcriptome RNA sequencing were utilized to examine the impact of C5orf34 on LUAD cells. According to our study, C5orf34 exhibits high expression levels in the majority of malignant tumors. The upregulation of C5orf34 is governed by DNA copy number alterations and methylation patterns, and it is closely associated with patients' survival prognosis and immune characteristics, thereby holding significant clinical implications. Furthermore, IHC staining analysis, cellular experiments, and transcriptome RNA sequencing have provided evidence supporting the role of C5orf34 in modulating the cell cycle to promote LUAD proliferation, migration, and invasion. This highlights its potential as a promising therapeutic target. The findings of this investigation suggest that C5orf34 may serve as a valuable biomarker for various tumor types and represent a potential target for immunotherapy, particularly in relation to the proliferation, migration, and apoptosis of LUAD cells.

Progestogen-driven B7-H4 contributes to onco-fetal immune tolerance

Immune tolerance mechanisms are shared in cancer and pregnancy. Through cross-analyzing single-cell RNA-sequencing data from multiple human cancer types and the maternal-fetal interface, we found B7-H4 (VTCN1) is an onco-fetal immune tolerance checkpoint. We showed that genetic deficiency of B7-H4 resulted in immune activation and fetal resorption in allogeneic pregnancy models. Analogously, B7-H4 contributed to MPA/DMBA-induced breast cancer progression, accompanied by CD8+ T cell exhaustion. Female hormone screening revealed that progesterone stimulated B7-H4 expression in placental and breast cancer cells. Mechanistically, progesterone receptor (PR) bound to a newly identified -58 kb enhancer, thereby mediating B7-H4 transcription via the PR-P300-BRD4 axis. PR antagonist or BRD4 degrader potentiated immunotherapy in a murine B7-H4+ breast cancer model. Thus, our work unravels a mechanistic and biological connection of a female sex hormone (progesterone) to onco-fetal immune tolerance via B7-H4 and suggests that the PR-P300-BRD4 axis is targetable for treating B7-H4+ cancer.

Lysosome-Targeting Bacterial Outer Membrane Vesicles for Tumor Specific Degradation of PD-L1

Increased expression of immune check point genes, such as PD-L1, is one of the main reasons for immunosuppression, especially for colon cancer. Development of novel therapeutic strategies is of great importance to improve the prognosis. In this study, outer membrane vesicles (OMV) derived from Gram-negative bacteria are engineered to immune checkpoint blockade nanosystem for efficient elicitation of anti-tumor immunity. Briefly, the OMVs are engineered with Lyp1-Traptavidin (S52G, R53D mutant of streptavidin) fusion protein displayed on the surface. The Lyp-1 endows the OMV with the capacity to target tumor tissues, while the Traptavidin ensures easy decoration of biotinylated anti-PD-L1 and biotinylated M6P (mannose 6-phosphate). The simultaneously anchored anti-PD-L1 and M6P (ligand for cation-independent mannose 6-phosphate receptor) on the engineered OMVs coordinately direct the membrane PD-L1 to lysosome for degradation, and thus unleash the anti-tumor immunity. With syngeneic tumor model, the engineered OMVs are confirmed to boost immunity, inhibit cancer growth, and thus prolong survival. Together, A proposed OMV-based modular nanosystem that enables assembly of biotinylated anti-PD-L1 and M6P on the surface for tumor-targeted immune checkpoint blockade.

Identification of immunotherapy-related subtypes, characterization of tumor microenvironment infiltration, and development of a prognostic signature in gastric carcinoma

BACKGROUND

Recent advances in immunotherapy have elicited a considerable amount of attention as viable therapeutic options for several cancer types, the present study aimed to explore the immunotherapy-related genes (IRGs) and develop a prognostic risk signature in gastric carcinoma (GC) based on these genes.

METHODS

IRGs were identified by comparing immunotherapy responders and non-responders in GC. Then, GC patients were divided into distinct subtypes by unsupervised clustering method based on IRGs, and the differences in immune characteristics and prognostic stratification between these subtypes were analyzed. An immunotherapy-related risk score (IRRS) signature was developed and validated for risk classification and prognosis prediction based on The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) cohorts. Besides, the predictive ability of the IRRS in immunotherapy response was also determined.

RESULTS

A total of 63 IRGs were identified, and 371 GC patients were stratified into two molecular subgroups with significantly different prognosis and immune characteristics. Then, an IRRS signature comprised of three IRGs (CENP8, NRP1, and SERPINE1) was constructed to predict the prognosis of GC patients in TCGA cohort. Importantly, external validation in multiple GEO cohorts further confirmed the universal applicability of the IRRS in distinct populations. Furthermore, we found that the IRRS was significantly correlated with patient's responsiveness to immunotherapy, GC patients with low IRRS are more likely to benefit from existing immunotherapy.

CONCLUSIONS

The risk score could serve as a robust prognostic biomarker, provide therapeutic benefits for immunotherapy and may be helpful for clinical decision making in GC patients.

Sialic Acids Blockade-Based Chemo-Immunotherapy Featuring Cancer Cell Chemosensitivity and Antitumor Immune Response Synergies

Immune checkpoint blockade (ICB) has significantly improved the prognosis of patients with cancer, although the majority of such patients achieve low response rates; consequently, new therapeutic approaches are urgently needed. The upregulation of sialic acid-containing glycans is a common characteristic of cancer-related glycosylation, which drives disease progression and immune escape via numerous pathways. Herein, the development of self-assembled core-shell nanoscale coordination polymer nanoparticles loaded with a sialyltransferase inhibitor, referred to as NCP-STI which effectively stripped diverse sialoglycans from cancer cells, providing an antibody-independent pattern to disrupt the emerging Siglec-sialic acid glyco-immune checkpoint is reported. Furthermore, NCP-STI inhibits sialylation of the concentrated nucleoside transporter 1 (CNT1), promotes the intracellular accumulation of anticancer agent gemcitabine (Gem), and enhances Gem-induced immunogenic cell death (ICD). As a result, the combination of NCP-STI and Gem (NCP-STI/Gem) evokes a robust antitumor immune response and exhibits superior efficacy in restraining the growth of multiple murine tumors and pulmonary metastasis. Collectively, the findings demonstrate a novel form of small molecule-based chemo-immunotherapy approach which features sialic acids blockade that enables cooperative effects of cancer cell chemosensitivity and antitumor immune responses for cancer treatment.

In Situ Synthesis of an Immune-Checkpoint Blocker from Engineered Bacteria Elicits a Potent Antitumor Response

Immune-checkpoint blockade (ICB) reinvigorates T cells from exhaustion and potentiates T-cell responses to tumors. However, most patients do not respond to ICB therapy, and only a limited response can be achieved in a "cold" tumor with few infiltrated lymphocytes. Synthetic biology can be used to engineer bacteria as controllable bioreactors to synthesize biotherapeutics in situ. We engineered attenuated Salmonella VNP20009 with synthetic gene circuits to produce PD-1 and Tim-3 scFv to block immunosuppressive receptors on exhausted T cells to reinvigorate their antitumor response. Secreted PD-1 and Tim-3 scFv bound PD-1+ Tim-3+ T cells through their targeting receptors in vitro and potentiated the T-cell secretion of IFN-γ. Engineered bacteria colonized the hypoxic core of the tumor and synthesized PD-1 and Tim-3 scFv in situ, reviving CD4+ T cells and CD8+ T cells to execute an antitumor response. The bacteria also triggered a strong innate immune response, which stimulated the expansion of IFN-γ+ CD4+ T cells within the tumors to induce direct and indirect antitumor immunity.

NOTCH3 as a prognostic biomarker and its correlation with immune infiltration in gastrointestinal cancers

NOTCH receptor 3 (NOTCH3) is known to regulate the transcription of oncogenes or tumor suppressor genes, thereby playing a crucial role in tumor development, invasion, maintenance, and chemotherapy resistance. However, the specific mechanism of how NOTCH3 drives immune infiltration in gastrointestinal cancer remains uncertain. The expression of NOTCH3 was analyzed through Western blot, PCR, Oncomine database, and the Tumor Immune Estimation Resource (TIMER) site. Kaplan-Meier plotter, PrognoScan database, and gene expression profile interactive analysis (GEPIA) were used to assess the impact of NOTCH3 on clinical prognosis. The correlation between NOTCH3 expression and immune infiltration gene markers was investigated using TIMER and GEPIA. NOTCH3 was found to be commonly overexpressed in various types of gastrointestinal tumors and was significantly associated with poor prognosis. Furthermore, the expression level of NOTCH3 showed a significant correlation with the tumor purity of gastrointestinal tumors and the extent of immune infiltration by different immune cells. Our findings suggest that NOTCH3 may act as a crucial regulator of tumor immune cell infiltration and can serve as a valuable prognostic biomarker in gastrointestinal cancers.

Identification and Validation of Tumor Microenvironment-Associated Signature in Clear-Cell Renal Cell Carcinoma through Integration of DNA Methylation and Gene Expression

The tumor microenvironment (TME) is crucial in tumor development, metastasis, and response to immunotherapy. DNA methylation can regulate the TME without altering the DNA sequence. However, research on the methylation-driven TME in clear-cell renal cell carcinoma (ccRCC) is still lacking. In this study, integrated DNA methylation and RNA-seq data were used to explore methylation-driven genes (MDGs). Immune scores were calculated using the ESTIMATE, which was employed to identify TME-related genes. A new signature connected with methylation-regulated TME using univariate, multivariate Cox regression and LASSO regression analyses was developed. This signature consists of four TME-MDGs, including AJAP1, HOXB9, MYH14, and SLC6A19, which exhibit high methylation and low expression in tumors. Validation was performed using qRT-PCR which confirmed their downregulation in ccRCC clinical samples. Additionally, the signature demonstrated stable predictive performance in different subtypes of ccRCC. Risk scores are positively correlated with TMN stages, immune cell infiltration, tumor mutation burden, and adverse outcomes of immunotherapy. Interestingly, the expression of four TME-MDGs are highly correlated with the sensitivity of first-line drugs in ccRCC treatment, especially pazopanib. Molecular docking indicates a high affinity binding between the proteins and pazopanib. In summary, our study elucidates the comprehensive role of methylation-driven TME in ccRCC, aiding in identifying patients sensitive to immunotherapy and targeted therapy, and providing new therapeutic targets for ccRCC treatment.

First-line hepatic arterial infusion chemotherapy plus lenvatinib and PD-(L)1 inhibitors versus systemic chemotherapy alone or with PD-(L)1 inhibitors in unresectable intrahepatic cholangiocarcinoma

PURPOSE

Limited treatment options exist for unresectable intrahepatic cholangiocarcinoma (ICC), with systemic chemotherapy (SC) serving as the primary approach. This study aimed to assess the effectiveness of first-line hepatic arterial infusion chemotherapy (HAIC) in combination with lenvatinib and PD-(L)1 inhibitors (HLP) compared to SC combined with PD-(L)1 inhibitors (SCP) or SC alone in treating unresectable ICC.

METHODS

Patient with unresectable ICC who underwent first-line treatment with HLP, SCP or SC from January 2016 to December 2022 were retrospectively analyzed. The study evaluated and compared efficacy and safety outcomes across the three treatment groups.

RESULTS

The study comprised 42, 49, and 50 patients in the HLP, SCP, and SC groups, respectively. Median progression-free survival (PFS) times were 30.0, 10.2, and 6.5 months for HLP, SCP, and SC groups. While the SC group had a median overall survival (OS) time of 21.8 months, the HLP and SCP groups hadn't reached median OS. The HLP group demonstrated significantly superior PFS (p < 0.001) and OS (p = 0.014) compared to the others. Moreover, the HLP group exhibited the highest objective response rate (ORR) at 50.0% and the highest disease control rate (DCR) at 88.1%, surpassing the SC group (ORR, 6.0%; DCR, 52.0%) and SCP group (ORR, 18.4%; DCR, 73.5%) (p < 0.05). Generally, the HLP group reported fewer grades 3-4 adverse events (AEs) compared with others.

CONCLUSION

In contrast to systemic chemotherapy with or without PD-(L)1 inhibitors, the triple combination therapy incorporating HAIC, lenvatinib, and PD-(L)1 inhibitors showcased favorable survival benefits and manageable adverse events for unresectable ICC.

Tumor-treating fields in cancer therapy: advances of cellular and molecular mechanisms

Tumor-Treating Fields (TTFields) use intermediate-frequency and low-intensity electric fields to inhibit tumor cells. However, their mechanisms are still not well understood. This article reviews their key antitumor mechanisms at the cellular and molecular levels, including inhibition of proliferation, induction of death, disturbance of migration, and activation of the immune system. The multifaceted biological effects in combination with other cancer treatments are also summarized. The deep insight into their mechanism will help develop more potential antitumor treatments.

Immunological nanomaterials to combat cancer metastasis

Metastasis causes greater than 90% of cancer-associated deaths, presenting huge challenges for detection and efficient treatment of cancer due to its high heterogeneity and widespread dissemination to various organs. Therefore, it is imperative to combat cancer metastasis, which is the key to achieving complete cancer eradication. Immunotherapy as a systemic approach has shown promising potential to combat metastasis. However, current clinical immunotherapies are not effective for all patients or all types of cancer metastases owing to insufficient immune responses. In recent years, immunological nanomaterials with intrinsic immunogenicity or immunomodulatory agents with efficient loading have been shown to enhance immune responses to eliminate metastasis. In this review, we would like to summarize various types of immunological nanomaterials against metastasis. Moreover, this review will summarize a series of immunological nanomaterial-mediated immunotherapy strategies to combat metastasis, including immunogenic cell death, regulation of chemokines and cytokines, improving the immunosuppressive tumour microenvironment, activation of the STING pathway, enhancing cytotoxic natural killer cell activity, enhancing antigen presentation of dendritic cells, and enhancing chimeric antigen receptor T cell therapy. Furthermore, the synergistic anti-metastasis strategies based on the combinational use of immunotherapy and other therapeutic modalities will also be introduced. In addition, the nanomaterial-mediated imaging techniques (e.g., optical imaging, magnetic resonance imaging, computed tomography, photoacoustic imaging, surface-enhanced Raman scattering, radionuclide imaging, etc.) for detecting metastasis and monitoring anti-metastasis efficacy are also summarized. Finally, the current challenges and future prospects of immunological nanomaterial-based anti-metastasis are also elucidated with the intention to accelerate its clinical translation.

Neurological Immune-Related Adverse Events Induced by Immune Checkpoint Inhibitors

The use of immune checkpoint inhibitors (ICIs) for the treatment of various advanced and aggressive types of malignancy has significantly increased both survival and long-term remission rates. ICIs block crucial inhibitory pathways of the immune system, in order to trigger an aggravated immune response against the tumor. However, this enhanced immune activation leads to the development of numerous immune-related adverse events (irAEs), which may affect any system. Although severe neurological irAEs are relatively rare, they carry a high disability burden, and they can be potentially life-threatening. Therefore, clinicians must be alert and act promptly when individuals receiving ICIs present with new-onset neurological symptoms. In this narrative review, we have collected all the currently available data regarding the epidemiology, pathogenesis, clinical manifestations, diagnosis, and treatment of post-ICI neurological irAEs. This review aims to raise physicians' awareness, enrich their knowledge regarding disease pathogenesis, and guide them through the diagnosis and management of post-ICI neurological irAEs.

Crosstalk between CXCL12/CXCR4/ACKR3 and the STAT3 Pathway

The reciprocal modulation between the CXCL12/CXCR4/ACKR3 axis and the STAT3 signaling pathway plays a crucial role in the progression of various diseases and neoplasms. Activation of the CXCL12/CXCR4/ACKR3 axis triggers the STAT3 pathway through multiple mechanisms, while the STAT3 pathway also regulates the expression of CXCL12. This review offers a thorough and systematic analysis of the reciprocal regulatory mechanisms between the CXCL12/CXCR4/ACKR3 signaling axis and the STAT3 signaling pathway in the context of diseases, particularly tumors. It explores the potential clinical applications in tumor treatment, highlighting possible therapeutic targets and novel strategies for targeted tumor therapy.

Nano-Delivery of Immunogenic Cell Death Inducers and Immune Checkpoint Blockade Agents: Single-Nanostructure Strategies for Enhancing Immunotherapy

Cancer immunotherapy has revolutionized oncology by harnessing the patient's immune system to target and eliminate cancer cells. However, immune checkpoint blockades (ICBs) face limitations such as low response rates, particularly in immunologically 'cold' tumors. Enhancing tumor immunogenicity through immunogenic cell death (ICD) inducers and advanced drug delivery systems represents a promising solution. This review discusses the development and application of various nanocarriers, including polymeric nanoparticles, liposomes, peptide-based nanoparticles, and inorganic nanoparticles, designed to deliver ICD inducers and ICBs effectively. These nanocarriers improve therapeutic outcomes by converting cold tumors into hot tumors, thus enhancing immune responses and reducing systemic toxicity. By focusing on single-nanoparticle systems that co-deliver both ICD inducers and ICBs, this review highlights their potential in achieving higher drug concentrations at tumor sites, improving pharmacokinetics and pharmacodynamics, and facilitating clinical translation. Future research should aim to optimize these nanocarrier systems for better in vivo performance and clinical applications, ultimately advancing cancer immunotherapy.

Programmed Death Ligand 1 (PD-L1) Expression in Lymphomas: State of the Art

The interaction of programmed death-1 (PD-1) on T lymphocytes with its ligands Programmed Death Ligand 1 (PD-L1) and Programmed Death Ligand 2 (PD-L2) on tumor cells and/or tumor-associated macrophages results in inhibitory signals to the T-cell receptor pathway, consequently causing tumor immune escape. PD-L1/PD-L2 are currently used as predictive tissue biomarkers in clinical practice. Virtually PD-L1 levels expressed by tumor cells are associated with a good response to immune checkpoint blockade therapies targeting the PD-1/PD-L1 axis. These therapies restore T-cell antitumor immune response by releasing T-lymphocytes from the inhibitory effects of tumor cells. Immune checkpoint therapies have completely changed the management of patients with solid cancers. This therapeutic strategy is less used in hematological malignancies, although good results have been achieved in some settings, such as refractory/relapsed classic Hodgkin lymphoma and primary mediastinal large B-cell lymphoma. Variable results have been obtained in diffuse large B-cell lymphoma and T-cell lymphomas. Immunohistochemistry represents the main technique for assessing PD-L1 expression on tumor cells. This review aims to describe the current knowledge of PD-L1 expression in various types of lymphomas, focusing on the principal mechanisms underlying PD-L1 overexpression, its prognostic significance and practical issues concerning the evaluation of PD-L1 immunohistochemical results in lymphomas.

Tailored Covalent Organic Framework Platform: From Multistimuli, Targeted Dual Drug Delivery by Architecturally Engineering to Enhance Photothermal Tumor Therapy

Engineering bulk covalent organic frameworks (COFs) to access specific morphological structures holds paramount significance in boosting their functions in cancer treatment; nevertheless, scant effort has been dedicated to exploring this realm. Herein, silica core-shell templates and multifunctional COF-based reticulated hollow nanospheres (HCOFs) are novelly designed as a versatile nanoplatform to investigate the simultaneous effect of dual-drug chemotherapy and photothermal ablation. Taking advantage of the distinct structural properties of the template, the resulting two-dimensional (2D) HCOF, featuring large internal voids and a peripheral interconnected mesoporous shell, presents intriguing benefits over its bulk counterparts for cancer treatment, including a well-defined morphology, an outstanding drug loading capability (99.6%) attributed to its ultrahigh surface area (2087 m2/g), great crystallinity, improved tumor accumulation, and an adjustable drug release profile. After being loaded with hydrophilic doxorubicin with a remarkable loading capacity, the obtained drug-loaded HCOFs were coated with gold nanoparticles (Au NPs) to confer them with three properties, including pore entrance blockage, active-targeting capability, and improved biocompatibility via secondary modification, besides high near infrared (NIR) absorption for efficient photothermal hyperthermia cancer suppression. The resultant structure was functionalized with mono-6-thio-β-cyclodextrin (β-CD) as a second pocket to load docetaxel as the hydrophobic anticancer agent (combination index = 0.33). The dual-drug-loaded HCOF displayed both pH- and near-infrared-responsive on-demand drug release. In vitro and in vivo evaluations unveiled the prominent synergistic performance of coloaded HCOF in cancer elimination upon NIR light irradiation. This work opens up a new avenue for exciting applications of structurally engineered HCOFs as hydrophobic/hydrophilic drug carriers as well as multimodal treatment agents.

Discovery of an efficacious KDM5B PROTAC degrader GT-653 up-regulating IFN response genes in prostate cancer

Epigenetic alterations promote cancer development by regulating the expression of various oncogenes and anti-oncogenes. Histone methylation modification represents a pivotal area in epigenetic research and numerous publications have demonstrated that aberrant histone methylation is highly correlated with tumorigenesis and development. As a key histone demethylase, lysine-specific demethylase 5B (KDM5B) demethylates lysine 4 of histone 3 (H3K4) and serves as a transcriptional repressor of certain tumor suppressor genes. Meanwhile, KDM5B inhibits STING-induced intrinsic immune response of tumor cells or recruits SETDB1 through non-enzymatic function to silence reverse transcription elements to promote immune escape. The conventional small molecule inhibitors can only inhibit the enzymatic function of KDM5B with no effect on the non-enzymatic function. In the article, we present the development of the first series of KDM5B degraders based on CPI-455 to inhibit the non-enzymatic function. Among them, GT-653 showed optimal KDM5B degradation efficiency in a ubiquitin proteasome-dependent manner. GT-653 efficiently reduced KDM5B protein levels without affecting KDM5B transcription. Interestingly, GT-653 increased H3K4me3 levels and activated the type-I interferon signaling pathway in 22RV1 cells without significant phenotypic response on cell proliferation.

Further knowledge and developments in resistance mechanisms to immune checkpoint inhibitors

The past decade has witnessed a revolution in cancer treatment, shifting from conventional drugs (chemotherapies) towards targeted molecular therapies and immune-based therapies, in particular immune-checkpoint inhibitors (ICIs). These immunotherapies release the host's immune system against the tumor and have shown unprecedented durable remission for patients with cancers that were thought incurable, such as metastatic melanoma, metastatic renal cell carcinoma (RCC), microsatellite instability (MSI) high colorectal cancer and late stages of non-small cell lung cancer (NSCLC). However, about 80% of the patients fail to respond to these immunotherapies and are therefore left with other less effective and potentially toxic treatments. Identifying and understanding the mechanisms that enable cancerous cells to adapt to and eventually overcome therapy can help circumvent resistance and improve treatment. In this review, we describe the recent discoveries on the onco-immunological processes which govern the tumor microenvironment and their impact on the resistance to PD-1/PD-L1 checkpoint blockade.

GSK0660 enhances antitumor immunotherapy by reducing PD-L1 expression

Blockade of PD-1/PD-L1 immune checkpoint is wildly used for multiple types of cancer treatment, while the low response rate for patients is still completely unknown. As nuclear hormone receptor, PPARδ (peroxisome-proliferator-activated receptor) regulates cell proliferation, inflammation, and tumor progression, while the effect of PPARδ on tumor immune escape is still unclear. Here we found that PPARδ antagonist GSK0660 significantly reduced colon cancer cell PD-L1 protein and gene expression. Luciferase analysis showed that GSK0660 decreased PD-L1 gene transcription activity. Moreover, reduced PD-L1 expression in colon cancer cells led to increased T cell activity. Further analysis showed that GSK0660 decreased PD-L1 expression in a PPARδ dependent manner. Implanted tumor model analysis showed that GSK0660 inhibited tumor immune escape and the combined PD-1 antibody with GSK0660 effectively enhanced colorectal cancer immunotherapy. These findings suggest that GSK0660 treatment could be an effective strategy for cancer immunotherapy.

Posttranslational regulatory mechanism of PD-L1 in cancers and associated opportunities for novel small-molecule therapeutics

Despite the tremendous progress in cancer research over the past few decades, effective therapeutic strategies are still urgently needed. Accumulating evidence suggests that immune checkpoints are the cause of tumor immune escape. PD-1/PD-L1 are among them. Posttranslational modification is the most critical step for protein function, and the regulation of PD-L1 by small molecules through posttranslational modification is highly valuable. In this review, we discuss the mechanisms of tumor cell immune escape and several posttranslational modifications associated with PD-L1 and describe examples in which small molecules can regulate PD-L1 through posttranslational modifications. Herein, we propose that the use of small molecule compounds that act by inhibiting PD-L1 through posttranslational modifications is a promising therapeutic approach with the potential to improve clinical outcomes for cancer patients.