Resistance Mechanisms of Anti-PD1/PDL1 Therapy in Solid Tumors

Resistance to PD-1/PD-L1 immune checkpoint blockade in advanced non-small cell lung cancer

Lung cancer is one of the most common malignant tumors, of which non-small cell lung cancer (NSCLC) accounts for about 85 %. Although immune checkpoint inhibitors (ICIs), particularly PD-1/PD-L1 inhibitors, have significantly improved the prognosis of patients with NSCLC. There are still many patients do not benefit from ICIs. Primary resistance remains a major challenge in advanced NSCLC. The cancer-immunity cycle describes the process from antigen release to T cell recognition and killing of the tumor, which provides a framework for understanding anti-tumor immunity. The classical cycle consists of seven steps, and alterations at each stage can result in resistance. This review examines the current status of PD-1/PD-L1 blockade in the treatment of advanced NSCLC and explores potential mechanisms of resistance. We summarize the latest clinical trials of PD-1/PD-L1 inhibitors combined with other therapies and explore potential targets for overcoming primary resistance to PD-1/PD-L1 inhibitors.

Interactions between long non-coding RNAs and m6 A modification in cancer

Long non-coding RNAs (lncRNAs) are a class of transcripts exceeding 200 nucleotides (nt) in length, which are broadly implicated in a broad spectrum of physiological and pathological processes, including allelic imprinting, genome packaging, chromatin remodeling, transcriptional activation and disruption, as well as the occurrence and progression of oncogenesis. N6-methyladenosine (m6 A) methylation stands as the most prevalent RNA modification, affecting multiple facets of RNA biology such as stability, splicing, transport, translation, degradation, and tertiary structure. Aberrant m6 A modifications are intimately implicated in cancer progression. In recent years, there has been a growing number of studies illuminating the dynamic interplay between lncRNAs and m6 A modifications, revealing that lncRNAs can modulate the activity of m6 A regulators, while m6 A not only affects the structural integrity but also the translational efficiency and stability of lncRNAs. Together, the interactions between lncRNAs and m6 A modifications significantly impact downstream oncogenes, cancer suppressor genes, cellular metabolism, epithelial-mesenchymal transition, angiogenesis, drug transport, DNA homology repair, and epigenetics, subsequently influencing tumorigenesis, metastasis, and drug resistance. This article endeavors to clarify the functions and mechanisms of lncRNAs and m6 A modifications interaction in cancer to provide promising insights for cancer diagnosis and therapeutic strategies.

Breast cancer patient-derived scaffolds enhance the understanding of PD-L1 regulation and T cell cytotoxicity

Recent advances as well as obstacles for immune-based cancer treatment strategies, highlight the notable impact of patient cancer microenvironments on the immune cells and immune targets. Here, we use patient-derived scaffolds (PDS) generated from 110 primary breast cancers to monitor the impact of the cancer microenvironment on immune regulators. Pronounced variation in PD-L1 expression is observed in cancer cells adapted to different patient scaffolds. This variation is further linked to clinical observations and correlated with specific proteins detected in the cell-free PDSs using mass spectrometry. When adding T cells to the PDS-based cancer cultures, the killing efficiency of activated T cells vary between the cultures, whereas non-activated T cells modulate the cancer cell PD-L1 expression to treatment-predictive values, matching killing capacities of activated T cells. Surviving cancer cells show enrichment in cancer stem cell and epithelial-to-mesenchymal transition (EMT) features, suggesting that T cells may not efficiently target cells with metastatic potential. We conclude that clinically relevant insights in how to optimally target and guide immune-based cancer therapies can be obtained by including patient-derived scaffolds and cues from the cancer microenvironment in cancer patient handling and drug development.

Enhancing antitumor immunity: the role of immune checkpoint inhibitors, anti-angiogenic therapy, and macrophage reprogramming

Cancer treatment has long been hindered by the complexity of the tumor microenvironment (TME) and the mechanisms that tumors employ to evade immune detection. Recently, the combination of immune checkpoint inhibitors (ICIs) and anti-angiogenic therapies has emerged as a promising approach to improve cancer treatment outcomes. This review delves into the role of immunostimulatory molecules and ICIs in enhancing anti-tumor immunity, while also discussing the therapeutic potential of anti-angiogenic strategies in cancer. In particular, we highlight the critical role of endoplasmic reticulum (ER) stress in angiogenesis. Moreover, we explore the potential of macrophage reprogramming to bolster anti-tumor immunity, with a focus on restoring macrophage phagocytic function, modulating hypoxic tumor environments, and targeting cytokines and chemokines that shape immune responses. By examining the underlying mechanisms of combining ICIs with anti-angiogenic therapies, we also review recent clinical trials and discuss the potential of biomarkers to guide and predict treatment efficacy.

The potential role of PD-1/PD-L1 small molecule inhibitors in colorectal cancer with different mechanisms of action

Colorectal cancer (CRC) remains one of the leading causes of cancer-related death worldwide, with increasing incidence in younger ages highlighting the need for new or alternative therapy, of which is immune checkpoint inhibitors. Antibody-based immune checkpoint inhibitors targeting the interaction between programmed cell death protein 1 (PD-1) and programmed death-ligand 1 (PD-L1) have revolutionized cancer treatment, including CRC. However, the low response rate in CRC highlights the need for additional research and innovative therapies. Small molecule inhibitors have risen as another strategy worth exploring, considering their potential to target a wide array of PD-1/PD-L1-related pathways. This review focuses on the potential of small molecule inhibitors targeting the PD-1/PD-L1 axis in CRC. Exploring various classes of small molecule inhibitors, including those that directly block the PD-1/PD-L1 interaction and others that target upstream regulators or downstream signaling pathways involved in PD-1/PD-L1-mediated immune suppression. Additionally, modulation of post-transcriptional and post-translational processes, thereby influencing the expression, stability, or localization of PD-1/PD-L1 proteins to enhance antitumor immunity, provides a multifaceted treatment approach. By disrupting these pathways, these inhibitors can restore immune system activity against tumor cells, offering new hope for overcoming resistance and improving outcomes in CRC patients who do not respond to conventional immune checkpoint inhibitors (ICIs). Integrating these small molecules into CRC treatment strategies could represent a promising advancement in the battle against the challenging disease.

The benefits of Lactiplantibacillus plantarum: From immunomodulator to vaccine vector

Probiotics have been increasingly recognized for positively influencing many aspects of human health. Lactiplantibacillus plantarum (L. plantarum), a non-pathogenic bacterium, previously known as Lactobacillus plantarum, is one of the lactic acid bacteria commonly used in fermentation. The probiotic properties of L. plantarum have highlighted its health benefits to humans when consumed in adequate amounts. L. plantarum strains primarily enter the body orally and alter intestinal microflora and modulate the immune responses in their host; thereby benefiting human health. Furthermore, the use of L. plantarum as vaccine vectors delivering mucosal antigens has been shown to be a promising strategy. These aspects, from Immunomodulation to vaccine delivery by L. plantarum in preclinical settings, are highlighted in this review. Along these lines, construction of a recombinant L. plantarum strain expressing a B cell multi-peptide, as a future vaccine to modulate immunity and confer anti-tumor effect by targeting Her-2/neu-overexpressing cancers in local and distal sites, is also presented and discussed.

New approaches of chimeric antigen receptor (CAR)-immune cell-based therapy in gastric cancer; highlight CAR-T and CAR-NK

One characteristic that makes gastric cancer (GC) against other cancers is the intricate immune system's reaction, particularly to tenacious inflammation. Consequently, the immunological function is essential to the growth of this malignancy. Tumor immunotherapy has yielded several encouraging outcomes, but despite this, different patients continue to not respond to treatment, and a far larger number become resistant to it. Also, activated CAR-T cells express a majority of immunological checkpoint factors, containing PD1, CTLA4, and LAG3, which counteracts the anti-tumor actions of CAR-T cells. Moreover, cytokine release syndrome is one of the possible adverse responses of CAR-T cell therapy. Therefore, producing universal allogeneic T lymphocytes with potent anti-tumor activity is essential. This study demonstrates current research on this cutting-edge technology, including the composition and mode of action of CAR-NK and CAR-T cells in GC. Also, in this study, we examined recent studies about various specific GC biomarkers that target CAR-T cells and CAR-NK cells.

An engineered PD1-Fc fusion produced in N. benthamiana plants efficiently blocks PD1/PDL1 interaction

KEY MESSAGE

Plant-made PD1-Fc fusions engineered for optimized glycosylation and Fc-receptor engagement are highly efficient in blocking PD1/PDL1 interactions and can be cost-effective alternatives to antibody-based immune checkpoint inhibitors. Immune checkpoint inhibitors (ICIs) are antibodies to receptors that have pivotal roles during T-cell activation processes. The programmed cell death 1 (PD1) can be regarded as the primary immune checkpoint and antibodies targeting PD1 or its ligand PDL1 have revolutionized immunotherapy of cancer. However, the majority of patients fail to respond, and treatment resistance as well as immune-related adverse events are commonly associated with this therapy. Alternatives to antibody-based ICIs targeting the PD1 pathway may bear the potential to overcome some of these shortcomings. Here, we have used a plant expression platform based on the tobacco relative Nicotiana benthamiana to generate immunoglobulin fusion proteins harboring the wild type or an affinity-enhanced PD1 ectodomain. We have exploited the versatility of our system to generate variants that differed regarding their glycosylation profile as well as their capability to engage Fc-receptors. Unlike its wild-type counterpart, the affinity-enhanced versions showed strongly augmented capabilities to engage PDL1 in both protein- and cell-based assays. Moreover, in contrast with clinical antibodies, their binding is not affected by the glycosylation status of PDL1. Importantly, we could demonstrate that the plant-made PD1 fusion proteins are highly efficient in blocking inhibitory PD1 signaling in a T cell reporter assay. Taken together, our study highlights the utility of our plant-based protein expression platform to generate biologics with therapeutic potential. Targeting PDL1 with plant derived affinity-enhanced PD1 immunoglobulin fusion proteins may reduce overstimulation associated with antibody-based therapies while retaining favorable features of ICIs such as long serum half-life.

Tetrahydrocurcumin alleviates colorectal tumorigenesis by modulating the SPP1/CD44 axis and preventing M2 tumor-associated macrophage polarization

BACKGROUND

Recent studies show that secreted phosphoprotein 1 (SPP1) is linked to the progression of various cancers, including colorectal cancer (CRC). SPP1 also promotes M2 macrophage polarization, contributing to immune evasion in the tumor microenvironment. Tetrahydrocurcumin (THC) has been reported to alleviate CRC, but the mechanism remains unclear.

PURPOSE

The study aimed to explore how THC modulated the SPP1/CD44 axis to inhibit M2 polarization and suppress CRC development.

METHODS

Azoxymethane/dextran sulfate sodium (AOM/DSS)-induced mouse model was used to assess the anti-CRC effects of THC. Transcriptome sequencing was conducted to identify the key targets of THC in CRC. The effects of THC on CRC cells were evaluated by CCK-8, colony formation, migration assays, immunofluorescence staining and flow cytometry. Human monocytic cells, THP-1, and colon cancer cell line, HCT116, were co-cultured, both directly or indirectly, to mimic the tumor-macrophage interactions, and investigate the role of SPP1/CD44 axis and the intervention effect of THC.

RESULTS

THC significantly inhibited CRC carcinogenesis in mice and improved pathologic symptoms, serum inflammatory markers, and intestinal barrier integrity. THC inhibited CRC cell proliferation, migration and colony formation, while promoting apoptosis. Transcriptome analysis identified SPP1 as a key target of THC against CRC. SPP1 facilitated CRC progression by activating the ERK signaling pathway and maintaining the M2-like phenotype of macrophage, which further exacerbated this response. THC inhibited CRC development by targeting the SPP1/CD44 axis, rather than the integrin pathway.

CONCLUSIONS

SPP1 played a crucial role in maintaining the M2 phenotype of macrophage and promoting CRC cells proliferation. THC inhibited the activation of ERK signals in CRC cells and phenotypic transformation of M2-like macrophages through the SPP1/CD44 axis, thereby regulating the tumor immune microenvironment to exert anti-CRC effect.

AI-enhanced profiling of phage-display-identified anti-TIM3 and anti-TIGIT novel antibodies

Antibody discovery is a lengthy and labor-intensive process, requiring extensive laboratory work to ensure that an antibody demonstrates the appropriate efficacy, production, and safety characteristics necessary for its use as a therapeutic agent in human patients. Traditionally, this process begins with phage display or B-cells isolation campaigns, where affinity serves as the primary selection criterion. However, the initial leads identified through this approach lack sufficient characterization in terms of developability and epitope definition, which are typically performed at late stages. In this study, we present a pipeline that integrates early-stage phage display screening with AI-based characterization, enabling more informed decision-making throughout the selection process. Using immune checkpoints TIM3 and TIGIT as targets, we identified five initial leads exhibiting similar binding properties. Two of these leads were predicted to have poor developability profiles due to unfavorable surface physicochemical properties. Of the remaining three candidates, structural models of the complexes formed with their respective targets were generated for 2: T4 (against TIGIT) and 6E9 (against TIM3). The predicted epitopes allowed us to anticipate a competition with TIM3 and TIGIT binding partners, and to infer the antagonistic functions expected from these antibodies. This study lays the foundations of a multidimensional AI-driven selection of lead candidates derived from high throughput analysis.

Immunogenicity and Safety Profile of Two Adjuvanted-PD-L1-Based Vaccine Candidates in Mice, Rats, Rabbits, and Cynomolgus Monkeys

BACKGROUND

The therapeutic blockade of the PD1/PD-L1 axis with monoclonal antibodies has led to a breakthrough in cancer treatment, as it plays a key role in the immune evasion of tumors. Nevertheless, treating patients with cancer with vaccines that stimulate a targeted immune response is another attractive approach for which few side effects have been observed in combination immunotherapy clinical trials. In this sense, our group has recently developed a therapeutic cancer vaccine candidate called PKPD-L1Vac which contains as an antigen the extracellular domain of human PD-L1 fused to a 47 amino-terminal, part of the LpdA gene of N. meningitides, which is produced in E. coli. The investigation of potential toxicities associated with PD-L1 blockade by a new therapy in preclinical studies is critical to optimizing the efficacy and safety of that new therapy.

METHODS

Here, we describe immunogenicity and preliminary safety studies in mice, rats, rabbits, and non-human primates that make use of a 200 μg dose of PKPD-L1 in combination with VSSPs or alum phosphate to contribute to the assessment of potential adverse events that are relevant to the future clinical development program of this novel candidate.

RESULTS

The administration of PKPD-L1Vac to the four species at the doses studied was immunogenic and did not result in behavioral, clinical, hematological, or serum biochemical changes.

CONCLUSIONS

Therefore, PKPD-L1Vac could be considered suitable for further complex toxicological studies and the way for its clinical evaluation in humans has been opened.

Impact of cannabinoids on cancer outcomes in patients receiving immune checkpoint inhibitor immunotherapy

Cannabinoids relieve pain, nausea, anorexia and anxiety, and improve quality of life in several cancer patients. The immunotherapy with checkpoint inhibitors (ICIs), although very successful in a subset of patients, is accompanied by moderate to severe immune-related adverse events (ir-AE) that often necessitate its discontinuation. Because of their role in symptomatic relief, cannabinoids have been used in combination with immune checkpoint inhibitor (ICI) immunotherapy. A few studies strongly suggest that the use of medicinal cannabis in cancer patients attenuates many of the ir-AE associated with the use of ICI immunotherapy and increase its tolerability. However, no significant beneficial effects on overall survival, progression free survival or cancer relapses were observed; rather, some of the studies noted adverse effects of concurrent administration of cannabinoids with ICI immunotherapy on the clinical benefits of the latter. Because of cannabinoids' well documented immunosuppressive effects mediated through the cannabinoid recptor-2 (CB2), we propose considering this receptor as an inhibitory immune checkpoint per se. A simultaneous neutralization of CB2, concurrent with cannabinoid treatment, may lead to better clinical outcomes in cancer patients receiving ICI immunotherapy. In this regard, cannabinoids such as cannabidiol (CBD) and cannabigerol (CBG), with little agonism for CB2, may be better therapeutic choices. Additional strategies e.g., the use of monoacylglycerol lipase (MAGL) inhibitors that degrade some endocannabinoids as well as lipogenesis and formation of lipid bilayers in cancer cells may also be explored. Future studies should take into consideration gut microbiota, CYP450 polymorphism and haplotypes, cannabinoid-drug interactions as well as genetic and somatic variations occurring in the cannabinoid receptors and their signaling pathways in cancer cells for personalized cannabis-based therapies in cancer patients receiving ICIs. This may lead to rational knowledge-based regimens tailored to individual cancer patients.

Revolutionary Cancer Therapy for Personalization and Improved Efficacy: Strategies to Overcome Resistance to Immune Checkpoint Inhibitor Therapy

Cancer remains a significant public health issue worldwide, standing as a primary contributor to global mortality, accounting for approximately 10 million fatalities in 2020 [...].

Antitumor Research Based on Drug Delivery Carriers: Reversing the Polarization of Tumor-Associated Macrophages

The development of malignant tumors is a complex process that involves the tumor microenvironment (TME). An immunosuppressive TME presents significant challenges to current cancer therapies, serving as a key mechanism through which tumor cells evade immune detection and play a crucial role in tumor progression and metastasis. This impedes the optimal effectiveness of immunotherapeutic approaches, including cytokines, immune checkpoint inhibitors, and cancer vaccines. Tumor-associated macrophages (TAMs), a major component of tumor-infiltrating immune cells, exhibit dual functionalities: M1-like TAMs suppress tumorigenesis, while M2-like TAMs promote tumor growth and metastasis. Consequently, the development of various nanocarriers aimed at polarizing M2-like TAMs to M1-like phenotypes through distinct mechanisms has emerged as a promising therapeutic strategy to inhibit tumor immune escape and enhance antitumor responses. This Review covers the origin and types of TAMs, common pathways regulating macrophage polarization, the role of TAMs in tumor progression, and therapeutic strategies targeting TAMs, aiming to provide a comprehensive understanding and guidance for future research and clinical applications.

Unveiling lactylation modification: A new hope for cancer treatment

This review article delves into the multifaceted role of lactylation modification in antitumor therapy, revealing the complex interplay between lactylation modification and the tumor microenvironment (TME), metabolic reprogramming, gene expression, and immunotherapy. As an emerging epigenetic modification, lactylation has a significant impact on the metabolic pathways of tumor cells, immune evasion, gene expression regulation, and sensitivity to chemotherapy drugs. Studies have shown that lactylation modification significantly alters the development and therapeutic response of tumors by affecting metabolites in the TME, immune cell functions, and signaling pathways. In the field of immunotherapy, the regulatory role of lactylation modification provides a new perspective and potential targets for tumor treatment, including modulating the sensitivity of tumors to immunotherapy by affecting the expression of immune checkpoint molecules and the infiltration of immune cells. Moreover, research progress on lactylation modification in various types of tumors indicates that it may serve as a biomarker to predict patients' responses to chemotherapy and immunotherapy. Overall, research on lactylation modification provides a theoretical foundation for the development of new tumor treatment strategies and holds promise for improving patient prognosis and quality of life. Future research will further explore the application potential of lactylation modification in tumor therapy and how to improve treatment efficacy by targeting lactylation modification.

Construction of a prognostic model and analysis of related mechanisms in breast cancer based on multiple datasets

Background

Breast cancer (BC) is a common tumor among women and is a heterogeneous disease with many subtypes. Each subtype shows different clinical presentations, disease trajectories and prognoses, and different responses to neoadjuvant therapy; thus, a new and universal prognostic biomarker for BC patients is urgently needed. Our goal is to identify a novel prognostic molecular biomarker that can accurately predict the outcome of all BC subtypes and guide their clinical management.

Methods

Utilizing data from The Cancer Genome Atlas (TCGA), we analyzed differential gene expression and patient clinical data. Weighted gene coexpression network analysis (WGCNA), Cox univariate regression and least absolute shrinkage and selection operator (LASSO) analysis were used to construct a prognostic model; the differential expression of the core genes in this model was validated via real-time quantitative polymerase chain reaction (RT-qPCR), and the reliability of the predictive model was validated in both an internal cohort and a BC patient dataset from the Gene Expression Omnibus (GEO) database. Further studies, such as gene set variation analysis (GSVA) and gene set enrichment analysis (GSEA), were performed to investigate the enrichment of signaling pathways. The CIBERSORT algorithm was used to estimate immune infiltration and tumor mutation burden (TMB), and drug sensitivity analysis was performed to evaluate the treatment response.

Results

A total of 1,643 differentially expressed genes were identified. After WGCNA and Cox regression combined with LASSO analysis, 15 genes were identified by screening and used to establish a prognostic gene signature. Further analysis revealed that the epithelial-mesenchymal transition (EMT) pathway gene signature was enriched in these genes. Each patient was assigned a risk score, and according to the median risk score, patients were classified into a high-risk group or a low-risk group. The prognosis of the low-risk group was better than that of the high-risk group (P<0.01), and analyses of two independent GEO validation cohorts yielded similar results. Furthermore, a nomogram was constructed and found to perform well in predicting prognosis. GSVA revealed that the EMT pathway, transforming growth factor β (TGF-β) signaling pathway and PI3K-Akt signaling pathway genes were enriched in the high-risk group, and the Wnt-β-catenin signaling pathway, DNA repair pathway and P53 pathway gene sets were enriched in the low-risk group. GSEA revealed genes related to TGF-β signaling and the PI3K-Akt signaling pathways were enriched in the high-risk group. CIBERSORT demonstrated that the low-risk group had greater infiltration of antitumor immune cells. The TMB and drug sensitivity results suggested that immunotherapy and chemotherapy are likely to be more effective in the low-risk group.

Conclusions

We established a new EMT pathway-related prognostic gene signature that can be used to effectively predict BC prognosis and treatment response.

Bibliometric analysis: a study of the microenvironment in cervical cancer (2000-2024)

Objective

The incidence of cervical cancer has increased in recent years. The tumor microenvironment (TME) is the local biological environment involved in tumor occurrence and development. This study aimed to conduct a comprehensive analysis of the global research on the TME in cervical cancer (CC), providing a knowledge framework in this field from a holistic and systematic perspective based on a bibliometric analysis.

Methods

Studies focusing on the TME in cervical cancer were searched using the Web of Science Core Collection database. The annual output, cooperation, hotspots, research status, and development trends in this field were analyzed using bibliometric softwares (VOSviewer and CiteSpace).

Results

A total of 1,057 articles published between 2000 and 2024 were selected. The number of publications and citations has recently increased. Cooperation network analysis indicated that China holds the foremost position in research on the TME in cervical cancer with the highest volume of publications, thus exerting the greatest influence. Fudan University had the highest output. Frontiers in Oncology showed the highest degree of productivity in this field. Rofstad, Einar K. made the most article contributions and was the most co-cited author. Four clusters were obtained after a cluster analysis of the keywords: TME, cervical cancer, immunotherapy, and prognosis. Immunotherapy, human papillomavirus, and biomarkers were relatively recent keywords that attracted increasing attention from researchers.

Discussion

This bibliometric analysis provides a data-based and objective introduction to the TME of cervical cancer, and offers readers a valuable reference for future research.

Conclusions

Comprehensive research in this field was mainly distributed in the TME of cervical cancer through the analysis of keywords and documents. Sufficient evidence supports mechanism research and application exploration. Further research should explore new topics related to the TME of cervical cancer.

Recombinant CD80 fusion protein combined with discoidin domain receptor 1 inhibitor for cancer treatment

Immune checkpoint inhibitors (ICIs) have significantly advanced the field of cancer immunotherapy. However, clinical data has shown that many patients have a low response rate or even resistance to immune checkpoint inhibitor alone. The underlying reasons for its poor efficacy include the deficiency of immune infiltration and effective CD28/CD80 costimulatory signal in tumor. Discoidin domain receptor 1 (DDR1) has been reported to be negatively related to immune cell infiltration in tumors. Herein, we constructed a soluble fusion protein using CD80, the natural ligand of CD28, in combination with DDR1 inhibitor. Our results demonstrated that CD80-Fc effectively activated T cells and inhibited tumor growth in vivo, even in tumors with poor efficacy of ICIs. Importantly, CD80-Fc fusion protein had a milder affinity against the targets which suggested a potential higher safety than CD28 agonists. Further, in order to promote tumor immune infiltration, we attempted to combine CD80-Fc fusion protein with DDR1 inhibitor for treatment. Our results indicated that using CD80-Fc fusion protein along with DDR1 inhibitor significantly promoted T cell infiltration in tumor microenvironment and more strongly inhibited tumor growth. Therefore, the combination use of CD80 fusion protein and DDR1 inhibitor could become an effective tumor immunotherapy strategy, potentially benefiting a larger number of patients. KEY POINTS: • We successfully constructed, expressed, and purified the recombinant CD80-Fc fusion protein • We demonstrated that CD80-Fc fusion protein has good safety and anti-tumor activity • We demonstrated that using CD80-Fc fusion protein along with DDR1 inhibitor can significantly promote immune infiltration of T cells in tumor microenvironment and more strongly inhibit tumor growth.

Integrative analysis of 5-methylcytosine associated signature in papillary thyroid cancer

Emerging evidence has indicated that m5C modification plays a vital role in cancer development. However, the function of m5C-lncRNAs in PTC has never been reported. This study aims to explore the regulation mechanism of m5C RNA methylation-related long noncoding RNAs (m5C-lncRNAs) in papillary thyroid cancer (PTC). Bioinformatics analysis was used to investigate the role of m5C-lncRNAs in the prognosis and tumor immune microenvironment of PTC. Subsequently, we preliminarily verified the regulation mechanisms of m5C-lncRNAs in vivo and in vitro experiments. A total of six m5C-lncRNAs and five immune cell types were selected to construct the risk score and immune risk score (IRS) model, respectively. Patients with a high-risk score had a worse prognosis and the ROC indicated a reliable prediction performance (AUC = 0.796). As expected, the ESTIMATE and immune scores were higher (P < 0.001) and the tumor purity (P < 0.05) was significantly lower in the low-risk subgroup. CIBERSORT analysis showed Tregs, M0 macrophages, dendritic cells resting, and eosinophils were positively correlated to the risk score. Moreover, the expression levels of PD-1, PD-L1, CTLA-4, TIM-3, LAG-3, and KLRB1 were lower in the high-risk subgroup. Importantly, patients in high-risk subgroup tended to have a better response to immunotherapy than those in low-risk subgroup (P = 0.022). Similar to the above risk score, the IRS model also showed favorable prognosis predictive performance (AUC = 0.764). An integrated nomogram combining risk score, IRS, and age exhibited good prognostic predictive performance. Additionally, we validate the downregulation of PPP1R12A-AS1 promotes proliferation and metastasis by activating the MAPK signaling pathway. Our research confirms that m5C-lncRNAs not only contribute to evaluating the prognosis of patients with PTC but also help predict immune cell infiltration and immunotherapy response.

Influence of lactate in resistance to anti‑PD‑1/PD‑L1 therapy: Mechanisms and clinical applications (Review)

Metabolic reprogramming is a prominent characteristic of tumor cells, evidenced by heightened secretion of lactate, which is linked to tumor progression. Furthermore, the accumulation of lactate in the tumor microenvironment (TME) influences immune cell activity, including the activity of macrophages, dendritic cells and T cells, fostering an immunosuppressive milieu. Anti‑programmed cell death protein 1 (PD‑1)/programmed death‑ligand 1 (PD‑L1) therapy is associated with a prolonged survival time of patients with non‑small cell lung cancer. However, some patients still develop resistance to anti‑PD‑1/PD‑L1 therapy. Lactate is associated with resistance to anti‑PD‑1/PD‑L1 therapy. The present review summarizes what is known about lactate metabolism in tumor cells and how it affects immune cell function. In addition, the present review emphasizes the relationship between lactate secretion and immunotherapy resistance. The present review also explores the potential for targeting lactate within the TME to enhance the efficacy of immunotherapy.

Advances in the understanding and therapeutic manipulation of cancer immune responsiveness: a Society for Immunotherapy of Cancer (SITC) review

Cancer immunotherapy-including immune checkpoint inhibition (ICI) and adoptive cell therapy (ACT)-has become a standard, potentially curative treatment for a subset of advanced solid and liquid tumors. However, most patients with cancer do not benefit from the rapidly evolving improvements in the understanding of principal mechanisms determining cancer immune responsiveness (CIR); including patient-specific genetically determined and acquired factors, as well as intrinsic cancer cell biology. Though CIR is multifactorial, fundamental concepts are emerging that should be considered for the design of novel therapeutic strategies and related clinical studies. Recent advancements as well as novel approaches to address the limitations of current treatments are discussed here, with a specific focus on ICI and ACT.

Chimeric antigen receptor macrophages (CAR-M) sensitize HER2+ solid tumors to PD1 blockade in pre-clinical models

We previously developed human CAR macrophages (CAR-M) and demonstrated redirection of macrophage anti-tumor function leading to tumor control in immunodeficient xenograft models. Here, we develop clinically relevant fully immunocompetent syngeneic models to evaluate the potential for CAR-M to remodel the tumor microenvironment (TME), induce T cell anti-tumor immunity, and sensitize solid tumors to PD1/PDL1 checkpoint inhibition. In vivo, anti-HER2 CAR-M significantly reduce tumor burden, prolong survival, remodel the TME, increase intratumoral T cell and natural killer (NK) cell infiltration, and induce antigen spreading. CAR-M therapy protects against antigen-negative relapses in a T cell dependent fashion, confirming long-term anti-tumor immunity. In HER2+ solid tumors with limited sensitivity to anti-PD1 (aPD1) monotherapy, the combination of CAR-M and aPD1 significantly improves tumor growth control, survival, and remodeling of the TME in pre-clinical models. These results demonstrate synergy between CAR-M and T cell checkpoint blockade and provide a strategy to potentially enhance response to aPD1 therapy for patients with non-responsive tumors.

Developing an Effective Therapeutic HPV Vaccine to Eradicate Large Tumors by Genetically Fusing Xcl1 and Incorporating IL-9 as Molecular Adjuvants

BACKGROUND

Human papillomavirus (HPV) is a prevalent infection affecting both men and women, leading to various cytological lesions. Therapeutic vaccines mount a HPV-specific CD8+ cytotoxic T lymphocyte response, thus clearing HPV-infected cells. However, no therapeutic vaccines targeting HPV are currently approved for clinical treatment due to limited efficacy. Our goal is to develop a vaccine that can effectively eliminate tumors caused by HPV.

METHODS

We genetically fused the chemokine XCL1 with the E6 and E7 proteins of HPV16 to target cDC1 and enhance the vaccine-induced cytotoxic T cell response, ultimately developing a DNA vaccine. Additionally, we screened various interleukins and identified IL-9 as an effective molecular adjuvant for our DNA vaccine.

RESULTS

The fusion of Xcl1 significantly improved the quantity and quality of the specific CD8+ T cells. The fusion of Xcl1 also increased immune cell infiltration into the tumor microenvironment. The inclusion of IL-9 significantly elevated the vaccine-induced specific T cell response and enhanced anti-tumor efficacy. IL-9 promotes the formation of central memory T cells.

CONCLUSIONS

the fusion of Xcl1 and the use of IL-9 as a molecular adjuvant represent promising strategies for vaccine development.

Gefitinib Reverses PD-L1-Mediated Immunosuppression Induced by Long-term Glutamine Blockade in Bladder Cancer

Glutamine is a major energy source for tumor cells, and blocking glutamine metabolism is being investigated as a promising strategy for cancer therapy. However, the antitumor effect of glutamine blockade in bladder cancer remains unclear, necessitating further investigation. In this study, we demonstrated that glutamine metabolism was involved in the malignant progression of bladder cancer. Treatment with the glutamine antagonist 6-diazo-5-oxo-L-norleucine (DON) inhibited the growth of bladder cancer cells in vitro in several ways. In addition, we observed inhibition of tumor growth in bladder cancer-bearing mice by using JHU083, a prodrug that was designed to prevent DON-induced toxicity. However, the antitumor immune effect of T cells changed from activation to inhibition as the administrated time extended. We found that both in vitro treatment with DON and in vivo prolonged administration of JHU083 led to the upregulation of PD-L1 in bladder cancer cells. Mechanistically, glutamine blockade upregulated PD-L1 expression in bladder cancer cells by accumulating reactive oxygen species, subsequently activating the EGFR/ERK/C-Jun signaling pathway. Combination treatment of JHU083 and gefitinib reversed the upregulation of PD-L1 in bladder cancer cells induced by prolonged glutamine blockade, resulting in the alleviation of T-cell immunosuppression and a significant improvement in therapeutic outcome. These preclinical findings show promise for glutamine metabolism targeting as a viable therapeutic strategy for bladder cancer, with the potential for further enhancement through combined treatment with gefitinib.

Characteristics of Soluble PD-L1 and PD-1 Expression and Their Correlations With Immune Status and Prognosis in Advanced Lung Cancer

PURPOSE

Our study aims to evaluate the characteristics of serum soluble PD-1 (sPD-1) and soluble PD-L1 (sPD-L1) levels and their correlations with immune status and prognosis in advanced lung cancer patients.

METHODS

Patients diagnosed with advanced lung cancer based on histology or cytology in Peking University People's Hospital from July 2020 to November 2021 were enrolled. Clinicopathological data were recorded and analyzed. Treatment efficacy was evaluated according to RESIST 1.1 criteria. The serum levels of sPD-L1 and sPD-1 were detected by enzyme-linked immunosorbent assay (ELISA). Lymphocyte subsets were measured by flow cytometry to evaluate the immune status of the patients.

RESULTS

A total of 65 patients with advanced lung cancer were enrolled. sPD-L1 level in lung cancer patients (15.67 ± 11.09 pg/mL, p = 0.001) was significantly higher than those in healthy controls (5.21 ± 4.46 pg/mL). sPD-1 level did not show a significant difference between patients with lung cancer and healthy controls. sPD-L1 level in patients with progressive disease (PD) was significantly higher than those with partial response (PR) (20.94 ± 8.91 vs. 13.14 ± 12.66 pg/mL, p = 0.033). In treatment-naïve patients, sPD-L1 level was negatively correlated with the lymphocyte ratio (correlation coefficient = -0.452, p = 0.014). Kaplan-Meier survival analysis showed that patients with low sPD-L1 level had a significantly longer progression-free survival (PFS) (10.4 vs. 5.7 months, p = 0.023). However, sPD-1 level did not correlate with lymphocyte subsets or prognosis in overall patients with lung cancer. Subgroup analysis showed that prolonged PFS in patients with low sPD-L1 level was exclusively shown in the NSCLC subgroup, not in the SCLC subgroup. In the subgroups of patients who subsequently received immunotherapy, low sPD-L1 level was correlated with longer PFS in the overall patients and NSCLC patients, and low sPD-1 level was correlated with longer PFS exclusively in NSCLC patients.

CONCLUSION

Serum sPD-L1 level was higher in patients with advanced lung cancer than healthy individuals, which was negatively correlated with the proportion of lymphocytes and prognosis. Serum sPD-1 level did not show significant difference between patients with lung cancer and healthy individuals, which showed no correlation with lymphocyte subsets and the prognosis of overall patients, except NSCLC patients receiving immunotherapy.

Current landscape of immunotherapy in esophageal cancer: a literature review

Background and Objective

Esophageal cancer has witnessed a significant shift in its epidemiology within the United States. Adenocarcinoma of the esophagus is now the fastest-growing solid malignancy, surpassing esophageal squamous cell carcinoma (ESCC) in frequency. There has been a concentrated effort to establish new therapies for dealing with this malignancy including immunotherapy in conjunction with surgery and radiotherapy. Our objective is to provide a comprehensive review of the current therapeutic strategies for esophageal cancer, with a particular focus on the emerging role of immunotherapy in combination with surgery and radiotherapy, and its impact on treatment outcomes.

Methods

A thorough search was done using keywords of "esophageal cancer", "immunotherapy in esophageal cancer", and "immunotherapy" in PubMed, MEDLINE, and Google Scholar databases. All studies that were identified in this search were analyzed for relevance and content.

Key Content and Findings

A total of 1,555 studies were identified which were checked for relevance and content. Fifteen articles were reviewed which focused on esophageal cancer and the immunotherapy directed towards this condition. This review article summarizes the most recent and available evidence on immunotherapy directed towards the treatment of esophageal cancer.

Conclusions

Esophageal cancer treatment is undergoing a paradigm shift with the advent of immunotherapy, particularly programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitors. These therapies hold promise for both second-line and first-line settings, with evolving biomarkers guiding treatment decisions. Combination strategies and personalized approaches are actively investigated to overcome resistance mechanisms and enhance treatment outcomes in this challenging cancer type.

DSN1 may predict poor prognosis of lower-grade glioma patients and be a potential target for immunotherapy

DSN1 has been previously found to be positively correlated with various cancers. However, the effect of DSN1 or its methylation on the prognosis, molecular characteristics, and immune cell infiltration of low-grade glioma (LGG) has not yet been studied. We obtained 1046 LGG samples from the The Cancer Genome Atlas, The Chinese Glioma Genome Atlas (CGGA) microarray, and CGGA RNA-Seq databases. Bioinformatic methods (gene set enrichment analysis (GSEA), chi-square test, multivariate), and laboratory validation were used to investigate DSN1 in LGG. The expression levels of DSN1 mRNA and protein in LGG were substantially higher than those in normal brain tissue, and their expression was negatively regulated by methylation. The survival time of patients with low expression of DSN1 and cg12601032 hypermethylation was considerably prolonged. DSN1 was a risk factor, and of good diagnostic and prognostic value for LGG. Importantly, the expression of DSN1 is related to many types of tumor-infiltrating immune cells and has a positive correlation with PDL1. DSN1 promoted the activation of multiple cancer-related pathways, such as the cell cycle. Additionally, knockdown of DSN1 substantially inhibited the proliferation and invasion of LGG cells. To the best of our knowledge, this study is the first comprehensive analysis of the mechanism of DSN1 leading to poor prognosis of LGG, which provides a new perspective for revealing the pathogenesis of LGG. DSN1 or its methylation has diagnostic value for the prognosis of glioma, and may become a new biological target of anti-tumor immunotherapy.

Enhanced Antiglioma Effect by a Vitamin D3-Inserted Lipid Hybrid Neutrophil Membrane Biomimetic Multimodal Nanoplatform

Glioblastoma, the most prevalent malignant brain tumor, is a lethal threat to human health, with aggressive and infiltrative growth characteristics that compromise the clinical treatment. Herein, we developed a vitamin D3-inserted lipid hybrid neutrophil membrane biomimetic multimodal nanoplatform (designated as NED@MnO2-DOX) through doxorubicin (DOX)-loaded manganese dioxide nanoparticles (MnO2) which were coated with a vitamin D3-inserted lipid hybrid neutrophil membrane. It was demonstrated that in addition to chemotherapy and chemo-dynamic therapy efficacy, NED@MnO2-DOX exhibited great power to activate and amplify immune responses related to the cGAS STING pathway, bolstering the secretion of type I interferon-β and proinflammatory cytokines, promoting the maturation of DC cells and infiltration of CD8+T cells into the glioma tissue, thereby reversing the immunosuppressive microenvironment of glioma from a "cold" tumor to a "hot" tumor. The biomimetic multimodal nanoplatform has potential as a multimodal strategy for glioma-targeted treatment, especially holding considerable promise for the development of innate immune therapy for glioma.

HDAC3 inhibitors induce drug resistance by promoting IL-17 A production by T cells

HDAC3 has been demonstrated to play a crucial role in the progression of various tumors and the differentiation and development of T cells. However, its impact on peripheral T cells in the development of murine lung cancer remains unclear. In this experiment, a subcutaneous lung tumor model was established in C57BL/6 mice, and tumor-bearing mice were treated with the specific inhibitor of HDAC3, RGFP966, at different doses to observe changes in tumor size. Additionally, a lung tumor model was established using hdac3fl/flcd4cre+/+ mice to investigate its mechanism. Mice injected with 10 mg/kg RGFP966 had the smallest tumor volume, while those injected with 30 mg/kg RGFP966 had the largest tumors. Flow cytometry analysis revealed that the expression of HDAC3 in splenic T cells was reduced in all groups of mice, while IFN-γ and IL-17 A were increased. Moreover, the expression of granzyme B and perforin in splenic CD8+ T cells was increased in all groups of mice. Compared to the use of 30 mg/kg RGFP966 alone, the combination with anti-IL-17 A mAb reduced the infiltration of Neutrophils and exhausted T cells in mouse tumors, thereby impeding tumor development. These findings demonstrate that the use of RGFP966 or T cell-specific loss of hdac3 promotes the expression of IL-17 A in splenic T cells, leading to tumor resistance and providing insights for clinical treatment.

A comprehensive review of immune checkpoint inhibitors for cancer treatment

Immunology-based therapies are emerging as an effective cancer treatment, using the body's immune system to target tumors. Immune checkpoints, which regulate immune responses to prevent tissue damage and autoimmunity, are often exploited by cancer cells to avoid destruction. The discovery of checkpoint proteins like PD-1/PD-L1 and CTLA-4 was pivotal in developing cancer immunotherapy. Immune checkpoint inhibitors (ICIs) have shown great success, with FDA-approved drugs like PD-1 inhibitors (Nivolumab, Pembrolizumab, Cemiplimab), PD-L1 inhibitors (Atezolizumab, Durvalumab, Avelumab), and CTLA-4 inhibitors (Ipilimumab, Tremelimumab), alongside LAG-3 inhibitor Relatlimab. Research continues on new checkpoints like TIM-3, VISTA, B7-H3, BTLA, and TIGIT. Biomarkers like PDL-1 expression, tumor mutation burden, interferon-γ presence, microbiome composition, and extracellular matrix characteristics play a crucial role in predicting responses to immunotherapy with checkpoint inhibitors. Despite their effectiveness, not all patients experience the same level of benefit, and organ-specific immune-related adverse events (irAEs) such as rash or itching, colitis, diarrhea, hyperthyroidism, and hypothyroidism may occur. Given the rapid advancements in this field and the variability in patient outcomes, there is an urgent need for a comprehensive review that consolidates the latest findings on immune checkpoint inhibitors, covering their clinical status, biomarkers, resistance mechanisms, strategies to overcome resistance, and associated adverse effects. This review aims to fill this gap by providing an analysis of the current clinical status of ICIs, emerging biomarkers, mechanisms of resistance, strategies to enhance therapeutic efficacy, and assessment of adverse effects. This review is crucial to furthering our understanding of ICIs and optimizing their application in cancer therapy.

Strategies for the enhancement of IL-21 mediated antitumor activity in solid tumors

Solid tumors significantly impact global health, necessitating enhanced prevention, early diagnosis, and treatment approaches. Tumor immunotherapy, notably through programmed cell death protein 1 (PD-1) and programmed cell death-ligand 1 (PD-L1), offers new hope to patients with advanced tumors, although many still do not benefit. Interleukin-21 (IL-21), a cytokine produced by certain immune cells, performs various biological functions by activating the JAK/STAT signaling pathway. Currently, recombinant IL-21 demonstrates promising antitumor activity and acceptable toxicity in several clinical trials. However, challenges such as side effects, off-target reactions, and a short half-life limit the effectiveness of cytokine-based immunotherapies. Therefore, researching enhanced IL-21 treatment strategies in solid tumors is crucial. Integrating IL-21 with various treatment modalities, including immune checkpoint inhibitors, additional cytokines, vaccines, or radiotherapy, is essential for improving response rates and prolonging patient survival. This review explores the specific mechanisms of IL-21 in prevalent high-incidence tumors, examines improved strategies for IL-21 in solid tumors, and aims to provide a theoretical basis for developing targeted treatment strategies.

Discovering explainable biomarkers for breast cancer anti-PD1 response via network Shapley value analysis

BACKGROUND AND OBJECTIVE

Immunotherapy holds promise in enhancing pathological complete response rates in breast cancer, albeit confined to a select cohort of patients. Consequently, pinpointing factors predictive of treatment responsiveness is of paramount importance. Gene expression and regulation, inherently operating within intricate networks, constitute fundamental molecular machinery for cellular processes and often serve as robust biomarkers. Nevertheless, contemporary feature selection approaches grapple with two key challenges: opacity in modeling and scarcity in accounting for gene-gene interactions METHODS: To address these limitations, we devise a novel feature selection methodology grounded in cooperative game theory, harmoniously integrating with sophisticated machine learning models. This approach identifies interconnected gene regulatory network biomarker modules with priori genetic linkage architecture. Specifically, we leverage Shapley values on network to quantify feature importance, while strategically constraining their integration based on network expansion principles and nodal adjacency, thereby fostering enhanced interpretability in feature selection. We apply our methods to a publicly available single-cell RNA sequencing dataset of breast cancer immunotherapy responses, using the identified feature gene set as biomarkers. Functional enrichment analysis with independent validations further illustrates their effective predictive performance RESULTS: We demonstrate the sophistication and excellence of the proposed method in data with network structure. It unveiled a cohesive biomarker module encompassing 27 genes for immunotherapy response. Notably, this module proves adept at precisely predicting anti-PD1 therapeutic outcomes in breast cancer patients with classification accuracy of 0.905 and AUC value of 0.971, underscoring its unique capacity to illuminate gene functionalities CONCLUSION: The proposed method is effective for identifying network module biomarkers, and the detected anti-PD1 response biomarkers can enrich our understanding of the underlying physiological mechanisms of immunotherapy, which have a promising application for realizing precision medicine.

Advances in Understanding Drug Resistance Mechanisms and Innovative Clinical Treatments for Melanoma

OPINION STATEMENT

Melanoma, a highly invasive skin cancer resulting from melanocyte malignant transformation, is the third most common skin malignancy. Despite accounting for only 4% to 5% of all skin malignancies, it is responsible for 80% of skin cancer-related deaths. Targeted therapies and immune checkpoint inhibitors have improved survival rates, yet drug resistance remains a major challenge. In this review, I explore the latest research progress on melanoma drug resistance mechanisms and clinical treatment methods. This aims to provide insights for more effective treatment strategies and improve patient prognosis and quality of life. I also discuss potential strategies to overcome drug resistance based on the latest scientific findings, with a particular focus on the complex and multi-factorial drug resistance mechanisms of melanomas, including genetic mutations, epigenetic changes, and tumor microenvironment factors. Understanding these mechanisms is crucial for developing new drugs and combination therapies targeting drug-resistant tumors. Analyzing complex drug resistance pathways paves the way for personalized medical approaches, which is expected to provide enlightenment on breaking through drug resistance barriers and enhancing the effectiveness of melanoma treatment.

Tumor Microenvironment Drives the Cross-Talk Between Co-Stimulatory and Inhibitory Molecules in Tumor-Infiltrating Lymphocytes: Implications for Optimizing Immunotherapy Outcomes

This review explores some of the complex mechanisms underlying antitumor T-cell response, with a specific focus on the balance and cross-talk between selected co-stimulatory and inhibitory pathways. The tumor microenvironment (TME) fosters both T-cell activation and exhaustion, a dual role influenced by the local presence of inhibitory immune checkpoints (ICs), which are exploited by cancer cells to evade immune surveillance. Recent advancements in IC blockade (ICB) therapies have transformed cancer treatment. However, only a fraction of patients respond favorably, highlighting the need for predictive biomarkers and combination therapies to overcome ICB resistance. A crucial aspect is represented by the complexity of the TME, which encompasses diverse cell types that either enhance or suppress immune responses. This review underscores the importance of identifying the most critical cross-talk between inhibitory and co-stimulatory molecules for developing approaches tailored to patient-specific molecular and immune profiles to maximize the therapeutic efficacy of IC inhibitors and enhance clinical outcomes.

The Potential of PD-1 and PD-L1 as Prognostic and Predictive Biomarkers in Colorectal Adenocarcinoma Based on TILs Grading

AIM

Colorectal cancer (CRC) is a prevalent malignancy with a high mortality rate. Tumor-infiltrating lymphocytes (TILs) play a crucial role in the immune response against tumors. Programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1) are key immune checkpoints regulating T cells in the tumor microenvironment. This study aimed to assess the relationships among PD-1 expression on TILs, PD-L1 expression in tumors, and TIL grading in colorectal adenocarcinoma.

METHODS

A cross-sectional design was employed to analyze 130 colorectal adenocarcinoma samples. The expression of PD-1 and PD-L1 was assessed through immunohistochemistry. A semi-quantitative scoring system was applied. Statistical analysis with the chi-square test was performed to explore correlations, with the data analyzed in SPSS version 27.

RESULTS

PD-1 expression on TILs significantly correlated with a higher TIL grading (p < 0.001), while PD-L1 expression in tumors showed an inverse correlation with TIL grading (p < 0.001).

CONCLUSIONS

The expression of PD-1 on TILs and PD-L1 on tumor cells correlated significantly with the grading of TILs in colorectal adenocarcinoma. This finding shows potential as a predictive biomarker for PD-1/PD-L1 blockade therapy. Further studies are needed to strengthen these results.

Unlocking Benzosampangine's Potential: A Computational Approach to Investigating, Its Role as a PD-L1 Inhibitor in Tumor Immune Evasion via Molecular Docking, Dynamic Simulation, and ADMET Profiling

The interaction between programmed cell death protein 1 (PD-1) and its ligand PD-L1 plays a crucial role in tumor immune evasion, presenting a critical target for cancer immunotherapy. Despite being effective, current monoclonal antibodies present some drawbacks such as high costs, toxicity, and resistance development. Therefore, the development of small-molecule inhibitors is necessary, especially those derived from natural sources. In this study, benzosampangine is predicted as a promising PD-L1 inhibitor, with potential applications in cancer immunotherapy. Utilizing the high-resolution crystal structure of human PD-L1 (PDB ID: 5O45), we screened 511 natural compounds, identifying benzosampangine as a top candidate with exceptional inhibitory properties. Molecular docking predicted that benzosampangine exhibits a strong binding affinity for PD-L1 (-9.4 kcal/mol) compared with established controls such as CA-170 (-6.5 kcal/mol), BMS-202 (-8.6 kcal/mol), and pyrvinium (-8.9 kcal/mol). The compound's predicted binding efficacy is highlighted by robust interactions with key amino acids (ILE54, TYR56, GLN66, MET115, ILE116, SER117, ALA121, ASP122) within the active site, notably forming 3 Pi-sulfur interactions with MET115-an interaction absents in control inhibitors. In addition, ADMET profiling suggests that over the control molecules, benzosampangine has several key advantages, including favorable solubility, permeability, metabolic stability, and low toxicity, while adhering to Lipinski's rule of five. Molecular dynamic simulations predict the stability of the benzosampangine-PD-L1 complex, reinforcing its potential to sustain inhibition of the PD-1/PD-L1 pathway. MMGBSA analysis calculated a binding free energy (ΔGbind) of -39.39 kcal/mol for the benzosampangine-PD-L1 complex, with significant contributions from Coulombic, lipophilic, and Van der Waals interactions, validating the predicted docking results. This study investigates in silico benzosampangine, predicting its better molecular interactions and pharmacokinetic profile compared with several already known PD-L1 inhibitors.

IMM2520, a novel anti-CD47/PD-L1 bispecific antibody for cancer immune therapy

PD-1/PD-L1 is an important signaling pathway in the adaptive immune system. The CD47/SIRPα signaling pathway is a crucial "do not eat me" signal for innate immunity. This study evaluated the anti-tumor mechanism of IMM2520 in vitro and in vivo. IMM2520 was generated using the "mab-trap" platform. IMM2520 showed high affinity to PD-L1 and relatively lower affinity to CD47, displaying preferential binding to PD-L1 on tumor cells. IMM2520 had the potent ability to inhibit the PD-1/PD-L1 and CD47/SIRPα signaling pathways and killed tumor cells through ADCC and ADCP. Importantly, IMM2520 did not bind to human red blood cells or induce erythrocyte agglutination. IMM2520 demonstrated a tendency to bind to CD47+/PD-L1+ tumor cells, reducing its binding to CD47 single-positive cells. In mouse transplantation models, compared with the first-generation CD47/PD-L1 BsAb (IMM2505), IMM2520 exhibited stronger and dose-dependent antitumor activity. These findings imply that IMM2520 may offer a novel therapeutic alternative for cancer patients.

GPD1L may inhibit the development of esophageal squamous cell carcinoma through the PI3K/AKT signaling pathway: bioinformatics analysis and experimental exploration

BACKGROUND

Esophageal squamous carcinoma (ESCC) is the most prevalent pathological subtype of esophageal cancer (EC). It has the characteristics of significant local invasion, quick disease progression, high recurrence rates, and a dismal prognosis for survival. Phosphatidylinositol 3-kinase/serine-threonine kinase (PI3K/AKT) is a signaling system whose aberrant activation regulates downstream factors, leading to the promotion of cancer development. This study looks at a protein called Glycerol-3-phosphate dehydrogenase 1-like (GPD1L), which strongly affects the development of several cancers. However, its association with ESCC development and its underlying mechanisms are not clear.

METHODS

In this paper, we analyzed six ESCC transcriptome data obtained from the GEO database. We utilized bioinformatics technology and immunohistochemistry to differentially analyze GPD1L levels of mRNA and protein expression in ESCC and normal adjacent tissues. Furthermore, we conducted survival, co-expression, enrichment, immune infiltration and drug sensitivity analysis. Moreover, we further investigated the role and mechanism of GPD1L by Western Blot (WB), Cell Counting Kit-8 (CCK8), wound healing assay, Transwell assay, and flow cytometry. Finally, the addition of IGF-1, the activator of PI3K/AKT, could rescue the inhibitory effect of GPD1L on ESCC.

RESULTS

The findings manifest that the expression of GPD1L was low in ESCC, and functional experiments showed that GPD1L promoted apoptosis in vitro while blocking cell migration, invasion, and proliferation. Based on mechanism research, GPD1L's impact on ESCC could be explained by its suppression of the PI3K/AKT signaling pathway's activation.

CONCLUSION

To sum up, our findings imply that GPD1L may impede the initiation and advancement of ESCC via modulating the PI3K/AKT signaling pathway. GPD1L is considered to be a promising therapeutic target and biomarker to diagnose and treat ESCC.

In situ editing of tumour cell membranes induces aggregation and capture of PD-L1 membrane proteins for enhanced cancer immunotherapy

Immune checkpoint blockade (ICB) therapy has emerged as a new therapeutic paradigm for a variety of advanced cancers, but wide clinical application is hindered by low response rate. Here we use a peptide-based, biomimetic, self-assembly strategy to generate a nanoparticle, TPM1, for binding PD-L1 on tumour cell surface. Upon binding with PD-L1, TPM1 transforms into fibrillar networks in situ to facilitate the aggregation of both bound and unbound PD-L1, thereby resulting in the blockade of the PD-1/PD-L1 pathway. Characterizations of TPM1 manifest a prolonged retention in tumour ( > 7 days) and anti-cancer effects associated with reinvigorating CD8+ T cells in multiple mice tumour models. Our results thus hint TPM1 as a potential strategy for enhancing the ICB efficacy.

T-cell Responses to Individualized Neoantigen Therapy mRNA-4157 (V940) Alone or in Combination with Pembrolizumab in the Phase 1 KEYNOTE-603 Study

mRNA-4157 (V940) is an individualized neoantigen therapy targeting up to 34 patient-specific tumor neoantigens to induce T-cell responses and potentiate antitumor activity. We report mechanistic insights into the immunogenicity of mRNA-4157 via characterization of T-cell responses to neoantigens from the first-in-human, phase 1, KEYNOTE-603 study (NCT03313778) in patients with resected non-small cell lung cancer (Part A: 1-mg mRNA-4157, n = 4) or resected cutaneous melanoma (Part D: 1-mg mRNA-4157 + 200-mg pembrolizumab, n = 12). Safety, tolerability, and immunogenicity were assessed. All patients experienced ≥1 treatment-emergent adverse event; there were no grade 4/5 adverse events or dose-limiting toxicities. mRNA-4157 alone induced consistent de novo and strengthened preexisting T-cell responses to targeted neoantigens. Following combination therapy, sustained mRNA-4157-induced neoantigen-specific T-cell responses and expansion of cytotoxic CD8 and CD4 T cells were observed. These findings show the potential of a novel mRNA individualized neoantigen therapy approach in oncology. Significance: The safety and immunogenicity results from this phase 1 study of mRNA-4157 as adjuvant monotherapy or combination therapy with pembrolizumab show generation of de novo and enhancement of existing neoantigen-specific T-cell responses and provide mechanistic proof of concept to support further development of mRNA-4157 for patients with resected solid tumors. See related commentary by Berraondo et al., p. 2021.

Integration of circadian rhythms and immunotherapy for enhanced precision in brain cancer treatment

Circadian rhythms significantly impact (patho)physiological processes, with disruptions linked to neurodegenerative diseases and heightened cancer vulnerability. While immunotherapy has shown promise in treating various cancers, its efficacy in brain malignancies remains limited. This review explores the nexus of circadian rhythms and immunotherapy in brain cancer treatment, emphasising precision through alignment with the body's internal clock. We evaluate circadian regulation of immune responses, including cell localisation and functional phenotype, and discuss how circadian dysregulation affects anti-cancer immunity. Additionally, we analyse and assess the effectiveness of current immunotherapeutic approaches for brain cancer including immune checkpoint blockades, adoptive cellular therapies, and other novel strategies. Future directions, such as chronotherapy and personalised treatment schedules, are proposed to optimise immunotherapy precision against brain cancers. Overall, this review provides an understanding of the often-overlooked role of circadian rhythms in brain cancer and suggests avenues for improving immunotherapeutic outcomes.

Natural killer cells and engagers: Powerful weapons against cancer

Natural killer (NK) cells are innate immune effectors whose functions rely on receptors binding cytokines, recognizing self-molecules, or detecting danger signals expressed by virus-infected or tumor cells. The potent cytotoxic potential makes NK cells promising candidates for cancer immunotherapy. To enhance their activity strategies include cytokine administration, blocking of immune checkpoints, and designing of antibody-based NK cell engagers (NKCEs). NKCEs represent a cutting-edge approach to cancer therapy: they strengthen the NK-to-target cell interactions and optimize tumor killing, possibly overcoming the immunosuppressive tumor microenvironment. NK cells belong to the innate lymphoid cells (ILCs) and are categorized into different subsets also including cells with a memory-like phenotype: this complexity needs to be explored in the context of cancer immunotherapy, particularly when designing NKCEs. Two strategies to enhance NK cell activity in cancer patients can be adopted: activating patients' own NK cells versus the adoptive transfer of ex vivo activated NK cells. Furthermore, the capability of NKCEs to activate γδ T cells could have a significant synergistic effect in immunotherapy.

Immunologic signatures of response and resistance to nivolumab with ipilimumab in advanced metastatic cancer

Identifying pan-tumor biomarkers that predict responses to immune checkpoint inhibitors (ICI) is critically needed. In the AMADEUS clinical trial (NCT03651271), patients with various advanced solid tumors were assessed for changes in intratumoral CD8 percentages and their response to ICI. Patients were grouped based on tumoral CD8 levels: those with CD8 <15% (CD8-low) received nivolumab (anti-PD-1) plus ipilimumab (anti-CTLA4) and those with CD8 ≥15% (CD8-high) received nivolumab monotherapy. 79 patients (72 CD8-low and 7 CD8-high) were treated. The disease control rate was 25.0% (18/72; 95% CI: 15.8-35.2) in CD8-low and 14.3% (1/7; 95% CI: 1.1-43.8) in CD8-high. Tumors from 35.9% (14/39; 95% CI: 21.8-51.4) of patients converted from CD8 <15% pretreatment to ≥15% after treatment. Multiomic analyses showed that CD8-low responders had an inflammatory tumor microenvironment pretreatment, enhanced by an influx of CD8 T cells, CD4 T cells, B cells, and macrophages upon treatment. These findings reveal crucial pan-cancer immunological features for ICI response in patients with metastatic disease.

Genetic variants of LRRC8C, OAS2, and CCL25 in the T cell exhaustion-related genes are associated with non-small cell lung cancer survival

Background

T cell exhaustion is a state in which T cells become dysfunctional and is associated with a decreased efficacy of immune checkpoint inhibitors. Lung cancer has the highest mortality among all cancers. However, the roles of genetic variants of the T cell exhaustion-related genes in the prognosis of non-small cell lung cancer (NSCLC) patients has not been reported.

Methods

We conducted a two-stage multivariable Cox proportional hazards regression analysis with two previous genome-wide association study (GWAS) datasets to explore associations between genetic variants in the T cell exhaustion-related genes and survival of NSCLC patients. We also performed expression quantitative trait loci analysis for functional validation of the identified variants.

Results

Of all the 52,103 single nucleotide polymorphisms (SNPs) in 672 T cell exhaustion-related genes, 1,721 SNPs were found to be associated with overall survival (OS) of 1185 NSCLC patients of the discovery GWAS dataset from the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial, and 125 of these 1,721 SNPs remained significant after validation in an additional independent replication GWAS dataset of 984 patients from the Harvard Lung Cancer Susceptibility (HLCS) Study. In multivariable stepwise Cox model analysis, three independent SNPs (i.e., LRRC8C rs10493829 T>C, OAS2 rs2239193 A>G, and CCL25 rs3136651 T>A) remained significantly associated with OS with hazards ratios (HRs) of 0.86 (95% confidence interval (CI) = 0.77-0.96, P = 0.008), 1.48 (95% CI = 1.18-1.85, P < 0.0001) and 0.78 (95% CI = 0.66-0.91, P = 0.002), respectively. Further combined analysis for these three SNPs suggested that an unfavorable genotype score was associated with a poor OS and disease-specific survival. Expression quantitative trait loci analysis suggested that the LRRC8C rs10493829 C allele was associated with elevated LRRC8C mRNA expression levels in normal lymphoblastoid cells, lung tissue, and whole blood.

Conclusion

Our findings suggested that these functional SNPs in the T cell exhaustion-related genes may be prognostic predictors for survival of NSCLC patients, possibly via a mechanism of modulating corresponding gene expression.

Bioconjugated Antibody-Trojan Immune Converter Enhance Cancer Immunotherapy with Minimized Toxicity by Programmed Two-Step Immunomodulation of Myeloid Cells

Current immune checkpoint blockade therapy (ICBT) predominantly targets T cells to harness the antitumor effects of adaptive immune system. However, the effectiveness of ICBT is reduced by immunosuppressive innate myeloid cells in tumor microenvironments (TMEs). Toll-like receptor 7/8 agonists (TLR7/8a) are often used to address this problem because they can reprogram myeloid-derived suppressor cells (MDSCs) and tumor-associated M2 macrophages, and boost dendritic cell (DC)-based T-cell generation; however, the systemic toxicity of TLR7/8a limits its clinical translation. Here, to address this limitation and utilize the effectiveness of TLR7/8a, this work suggests a programmed two-step activation strategy via Antibody-Trojan Immune Converter Conjugates (ATICC) that specifically targets myeloid cells by anti-SIRPα followed by reactivation of transiently inactivated Trojan TLR7/8a after antibody-mediated endocytosis. ATICC blocks the CD47-SIRPα ("don't eat me" signal), enhances phagocytosis, reprograms M2 macrophages and MDSCs, and increases cross-presentation by DCs, resulting in antigen-specific CD8+ T-cell generation in tumor-draining lymph nodes and TME while minimizing systemic toxicity. The local or systemic administration of ATICC improves ICBT responsiveness through reprogramming of the immunosuppressive TME, increased infiltration of antigen-specific CD8+ T cells, and antibody-dependent cellular phagocytosis. These results highlight the programmed and target immunomodulation via ATICC could enhance cancer immunotherapy with minimized systemic toxicities.

High MAL2 expression predicts shorter survival in women with triple-negative breast cancer

INTRODUCTION

Due to its lack of conventional surface receptors, triple-negative breast cancer (TNBC) is inherently resistant to most targeted therapies. MAL2 overexpression prompts endocytosis, conferring resistance to novel therapeutics. This study explores the role of MAL2 and PD-L1 in TNBC patients' prognosis.

METHODS

We performed immunohistochemical analysis on 111 TNBC samples collected from 76 patients and evaluated the expression of MAL2 and PD-1. We expanded the study by including The Cancer Genome Atlas (TCGA) cohort.

RESULTS

MAL2 expression did not correlate with stage, grade, tumor size, lymph node invasion, metastasis, and PD-1 expression. Patients with high MAL2 had significantly lower 5-year survival rates (71.33% vs. 89.59%, p = 0.0224). In the tissue microarray cohort (TMA), node invasions, size, recurrence, and low MAL2 (HR 0.29 [CI 95% 0.087-0.95]; p < 0.05) predicted longer patients' survival. In the TCGA cohort, patients with low MAL2 had significantly longer overall survival and disease-specific survival than patients with high MAL2. Older age and high MAL2 expression were the only independent predictors of shorter patient survival in the BRCA TCGA cohort.

CONCLUSION

High MAL2 predicts unfavorable prognosis in triple-negative breast cancer, and its expression is independent of PD-1 levels and clinicopathological features of TNBC.

The advancements and prospective developments in anti-tumor targeted therapy

Cancer poses a major threat to human health worldwide. The development of anti-tumor materials provides new modalities for cancer diagnosis and treatment. In this review, we comprehensively summarize the research progress and clinical applications of anti-tumor materials. First, we introduce the etiology and pathogenesis of cancer, and the significance and challenges of anti-tumor materials research. Then, we classify anti-tumor materials and discuss their mechanisms of action. After that, we elaborate the research advances and clinical applications of anti-tumor materials, including those targeting tumor cells and therapeutic instruments. Finally, we discuss the future perspectives and challenges in the field of anti-tumor materials. This review aims to provide an overview of the current status of anti-tumor materials research and application, and to offer insights into future directions in this rapidly evolving field, which holds promise for more precise, efficient and customized treatment of cancer.

Bispecific antibodies: advancing precision oncology

Bispecific antibodies (bsAbs) are engineered molecules designed to target two different epitopes or antigens. The mechanism of action is determined by the bsAb molecular targets and structure (or format), which can be manipulated to create variable and novel functionalities, including linking immune cells with tumor cells, or dual signaling pathway blockade. Several bsAbs have already changed the treatment landscape of hematological malignancies and select solid cancers. However, the mechanisms of resistance to these agents are understudied and the management of toxicities remains challenging. Herein, we review the principles in bsAb engineering, current understanding of mechanisms of action and resistance, data for clinical application, and provide a perspective on ongoing challenges and future developments in this field.

The miRNA and PD-1/PD-L1 signaling axis: an arsenal of immunotherapeutic targets against lung cancer

Lung cancer is a severe challenge to the health care system with intrinsic resistance to first and second-line chemo/radiotherapies. In view of the sterile environment of lung cancer, several immunotherapeutic drugs including nivolumab, pembrolizumab, atezolizumab, and durvalumab are currently being used in clinics globally with the intention of releasing exhausted T-cells back against refractory tumor cells. Immunotherapies have a limited response rate and may cause immune-related adverse events (irAEs) in some patients. Hence, a deeper understanding of regulating immune checkpoint interactions could significantly enhance lung cancer treatments. In this review, we explore the role of miRNAs in modulating immunogenic responses against tumors. We discuss various aspects of how manipulating these checkpoints can bias the immune system's response against lung cancer. Specifically, we examine how altering the miRNA profile can impact the activity of various immune checkpoint inhibitors, focusing on the PD-1/PD-L1 pathway within the complex landscape of lung cancer. We believe that a clear understanding of the host's miRNA profile can influence the efficacy of checkpoint inhibitors and significantly contribute to existing immunotherapies for lung cancer patients. Additionally, we discuss ongoing clinical trials involving immunotherapeutic drugs, both as standalone treatments and in combination with other therapies, intending to advance the development of immunotherapy for lung cancer.

H3K9 lactylation in malignant cells facilitates CD8+ T cell dysfunction and poor immunotherapy response

Histone lysine lactylation (Kla) is a post-translational modification, and its role in tumor immune escape remains unclear. Here, we find that increased histone lactylation is associated with poor response to immunotherapy in head and neck squamous cell carcinoma (HNSCC). H3K9la is identified as a specific modification site in HNSCC. Using cleavage under targets and tagmentation analyses, interleukin-11 (IL-11) is identified as a downstream regulatory gene of H3K9la. IL-11 transcriptionally activates immune checkpoint genes through JAK2/STAT3 signaling in CD8+ T cells. Additionally, IL-11 overexpression promotes tumor progression and CD8+ T cell dysfunction in vivo. Moreover, IL11 knockdown reverses lactate-induced CD8+ T cell exhaustion, and cholesterol-modified siIL11 restores CD8+ T cell killing activity and enhances immunotherapy efficacy. Clinically, H3K9la positively correlates with IL-11 expression and unfavorable immunotherapy responses in patients. This study reveals the crucial role of histone lactylation in immune escape, providing insights into immunotherapy strategies for HNSCC.