PD-1/PD-L1 Checkpoint Inhibitors in Tumor Immunotherapy

Advances in targeted therapy for triple-negative breast cancer: a review of key antigens and recent advances

The most aggressive subtype of breast cancer is triple-negative breast cancer (TNBC), which affects about 10-15% of all breast cancer cases. TNBC is associated with a poor prognosis and drug resistance due to the lack of oestrogen, progesterone, and HER2 receptors. Developing targeted immunotherapy for TNBC was challenged by identifying TNBC-specific antigens that can be suitable targets for antibody and nanobody-based therapies. Evidence from cancer- targeted therapy demonstrates that treatment outcomes are more successful when the target antigen is either overexpressed in tumour tissue or exhibits tumour specificity. Several antigens have been overexpressed in TNBC, including programmed cell death protein 1 (PD-1), programmed death-ligand 1(PD-L1), mesothelin (MSLN), trophoblast cell-surface antigen 2 (Trop-2), tumour endothelial marker 8 (TEM8), etc. There have been investigations targeting these antigens with antibodies, nanobodies, small molecules, peptides, and miniproteins for targeted treatment of TNBC. Antibodies known as Aembrolizumab, Atezolizumab, and Sacituzumab Govitecan-hziy have been approved by the FDA, and many are under investigation. The present review discusses the antigens with high expression in TNBC, their role in cancer development and progression, and the targeted therapies like antibodies, recombinant proteins, and antibody-drug conjugates (ADC).

High‑dose sodium propionate contributes to tumor immune escape through the IGF2BP3/PD‑L1 axis in colorectal cancer

The understanding of how gut microbiota metabolites modulate immune escape mechanisms in colorectal cancer (CRC) remains limited. In the present study, the impact of gut microbiota metabolites on the efficacy of programmed cell death protein 1 (PD-1) and programmed cell death ligand-1 (PD-L1) immunotherapy in CRC was explored, with a particular focus on the short-chain fatty acid, sodium propionate (SP), as they key metabolite. The results of the present study, determined by CCK-8 and flow cytometry, demonstrated that 10 mM SP significantly suppressed CRC cell proliferation and induced apoptosis. By contrast, 40 mM SP, but not 10 mM, markedly increased the PD-L1 mRNA and protein expression levels. Insulin-like growth factor 2 mRNA binding protein 3 (IGF2BP3) expression, analyzed via bioinformatics using The Cancer Genoma Atlas datasets, was significantly higher in CRC tissues compared with healthy tissues. Additionally, survival analysis uncovered that elevated IGF2BP3 levels in tumor tissues were strongly associated with poor clinical outcomes. Moreover, 40 mM SP significantly induced the expression of IGF2BP3 mRNA and protein in CRC cells. The actinomycin D assay was conducted to assess mRNA stability, whereas methylated RNA immunoprecipitation coupled with quantitative polymerase chain reaction (qPCR) and RNA immunoprecipitation-qPCR were utilized to confirm the interaction between IGF2BP3 and PD-L1 mRNA. These results indicated that IGF2BP3 served as an N6-methyladenosine (m6A) reader for PD-L1, stabilizing its mRNA in an m6A-dependent manner, thereby upregulating the PD-L1 mRNA and protein expression levels. Therefore, high-dose SP may promote tumor immune escape via the IGF2BP3/PD-L1 axis in CRC. As such, high-dose SP may synergize with PD-1/PD-L1 blockade therapies to improve clinical outcomes in patients with CRC, particularly by upregulating PD-L1 expression.

The Era of Precision Medicine: Advancing Treatment Paradigms for Small Cell Lung Cancer

Small cell lung cancer (SCLC) remains a challenge prognostically. A clinically silent early stage and predilection for early metastasis leads to over half of patients presenting with metastatic disease at the time of diagnosis. Akin to many other cancers, once SCLC metastasizes, current therapies begin to lose their effectiveness. The future of SCLC rests in innovative treatments aimed at improving patient outcomes. Chemotherapy and radiation remain the backbone treatment for SCLC. Most patients diagnosed with SCLC begin treatment with combination chemotherapy consisting of a platinum analog and topoisomerase inhibitor with or without concurrent radiation. Disease progression or recurrence warrants new treatment approaches. New chemotherapy combinations and advances in radiation precision offer patients novel approaches using the same backbone of treatment used in many other cancers. The introduction of newer therapeutic approaches, such as immune checkpoint inhibitors, small molecule targeted therapies, bispecific antibodies, and antibody-drug conjugates offer a bright future for patients with SCLC who fail first-line therapy. This review will focus on advancing treatment paradigms for SCLC in the era of precision medicine. Such a study might be helpful for pulmonologists and oncologists to manage precisely patients with SCLC.

Unlocking the potential of immune checkpoint inhibitors in advanced cervical cancer: a meta-analysis and systematic review

OBJECTIVE

This meta-analysis systematically evaluated the effectiveness and safety of immune checkpoint inhibitors (ICIs) in treating advanced cervical cancer, emphasizing their potential as transformative therapeutic options in this complex clinical landscape.

METHODS

EMBASE, Web of Science, PubMed, and the Cochrane Library were thoroughly searched for articles on the outcomes of ICIs in advanced cervical cancer patients. A pooled analysis was performed to evaluate the objective response rate (ORR: reported as an odds ratio (OR), progression-free survival (PFS; hazard ratio (HR), overall survival (OS; HR), and safety outcomes risk ratio (RR). Subgroup and sensitivity analyses were also conducted to identify potential sources of bias and heterogeneity.

RESULTS

Our meta-analysis included 5 studies involving 3,112 patients. Compared with standard therapies, treatment with immune checkpoint inhibitors (ICIs) significantly improved the objective response rate (ORR; OR = 1.68, 95% CI = 1.27-2.23), prolonged progression-free survival (PFS; HR = 0.72, 95% CI = 0.65-0.80), and extended overall survival (OS; HR = 0.69, 95% CI = 0.61-0.79). Subgroup analyses revealed potential predictors of treatment response. Moreover, ICIs exhibit a manageable safety profile, with adverse events consistent with known immune-related toxicities.

CONCLUSION

This meta-analysis highlights the promising efficacy and favourable safety profile of immune checkpoint inhibitors in advanced cervical cancer. These findings suggest a paradigm shift in treatment strategies, with ICIs emerging as a potential cornerstone therapy. Further research is warranted to elucidate optimal patient selection, combination therapies, and long-term outcomes. This study provides valuable insights for clinicians and researchers, paving the way for personalized and effective treatment approaches for advanced cervical cancer.

Unraveling the Specific Recognition Between PD-L1 and Engineered CLP002 Functionalized Gold Nanostructures: MD Simulation Studies

PD-L1 (programmed cell death ligand-1) is a protein located on the surface of regulatory cells. It has an immunosuppressive role as it binds specifically to the protein programmed cell death-1 (PD-1), a checkpoint glycoprotein, present on the surface of immune cells such as T and B lymphocytes. Many tumor cells block the immune response by overexpressing PD-L1 on their surface; therefore, targeting PD-L1 represents a powerful strategy that allows tumor localization. To determine the presence of PD-L1 in cells, the use of ad hoc functionalized peptides that bind to PD-L1 can be exploited. One of them is the peptide CLP002 (Trp-His-Arg-Ser-Tyr-Tyr-Thr-Trp-Asn-Leu-Asn-Thr), which, bound to surface-enhanced Raman scattering (SERS) gold nanostructures via a suitable linker, was shown to be highly effective in recognizing MDA-MB-231 breast cancer cells and, importantly, this recognition can be measured by SERS experiments. To characterize, on a molecular scale, the interaction between PD-L1 and peptide functionalized nanostructures, we performed molecular dynamics (MDs) simulations, studying the features of peptide monolayers bound on gold surfaces in the absence and presence of PD-L1. The results obtained allow us to explain why the nature of the linker plays a fundamental role in the binding and why a peptide carrying the same amino acids as CPL002 but with a different sequence (scrambled) is much less active than CLP002. These results open the way to an in silico evaluation of the key parameters that regulate the binding of PD-L1 useful for cancer recognition.

Newer Immunosuppressants for Rheumatologic Disease: Preoperative Considerations

With the advent of small-molecule immune modulators, recombinant fusion proteins, and monoclonal antibodies, treatment options for patients with rheumatic diseases are now broad. These agents carry significant risks and an individualized approach to each patient, balancing known risks and benefits, remains the most prudent course. This review summarizes the available immunosuppressant treatments, discusses their perioperative implications, and provides recommendations for their perioperative management.

The Role of Monoclonal Antibodies as Therapeutics in HPV-Related Head and Neck Cancers: An Updated Review

BACKGROUND/OBJECTIVES

The increasing prevalence of human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (OPSCC) has necessitated a revaluation of therapeutic strategies. HPV-driven OPSCC differs from HPV-negative OPSCC due to its distinct molecular signatures, increased radiosensitivity, and better prognoses. However, despite these differences, treatment strategies have remained largely uniform, resulting in minimal reductions in morbidity and exposing HPV-positive patients to unnecessary toxicity. Monoclonal antibodies (mAbs) have become a promising therapeutic option due to their ability to target treatment with fewer systemic side effects. Immune checkpoint inhibitors (ICIs) such as pembrolizumab have shown efficacy in enhancing the immune response against tumors, while EGFR inhibitors like cetuximab offer an alternative modality. Current clinical trials aim to refine dosing regimens and identify combination strategies that may enhance therapeutic outcomes.

RESULTS

Despite promising evidence, several challenges hinder the widespread adoption of mAbs as a standard treatment for HPV-positive OPSCC in clinical practice. This review examines the current role of mAbs in HPV-positive OPSCC treatment, highlighting their limitations and future research directions.

CONCLUSIONS

Further studies are needed to optimize patient selection, establish standardized treatment protocols, and investigate the long-term benefits of mAb-based therapies in this patient population.

Multimodal Imaging Demonstrated a Case of Buccal Cancer Cardiac Metastases Treated With Immune Checkpoint Inhibitor Therapy

A 35-year-old man with recurrent oral cancer underwent restaging FDG PET/CT imaging, which revealed neck lymph node metastasis and multiple distant metastases, including involvement of the right atrium, right ventricle, and pericardium. Doppler echocardiography and cardiac MRI confirmed the cardiac metastases while demonstrating preserved left ventricular systolic function. Follow-up FDG PET/CT imaging at 3 and 6 months after immune checkpoint inhibitor therapy, initiated due to high PD-L1 expression in the primary tumor, showed complete remission.

PD‑1/PD‑L1 immune checkpoint in bone and soft tissue tumors (Review)

Anti-programmed cell death 1 (PD-1)/PD-1 ligand-1 (PD-L1) drugs have been used clinically, including those for skin cancer, with reasonable efficacy. Despite extensive ongoing research on bone and soft tissue sarcomas, there is a paucity of reviews that present a coherent picture. The present article is a comprehensive narrative review on the role of the PD-1/PD-L1 immune checkpoint in bone and soft tissue tumors. The review outlines the biological functions and mechanisms of action of PD-1/PD-L1 and its expression and clinical significance in various tumor types, including osteosarcoma and soft tissue sarcoma. Clinical trial results of immune checkpoint inhibitors, their association with prognosis, mechanisms of resistance to therapy, immune-related adverse events, and their potential in combination therapies, were also discussed.

Epigenetic regulators combined with tumour immunotherapy: current status and perspectives

Immunotherapy, particularly immune checkpoint inhibitor therapy, has demonstrated clinical benefits in solid tumours. Despite its satisfactory clinical efficacy, it still faces several issues, such as limited eligibility, low response rates and cytotoxicity. Cancer epigenetics implies that tumour cells exhibit unique phenotypes because of their unique characteristics, thus reprogramming of the epigenome holds promise for cancer therapy. Epigenetic regulation plays an important role in regulating gene expression during tumour development and maintenance. Epigenetic regulators induce cancer cell cycle arrest, apoptosis and differentiation of cancer cells, thereby exerting anti-tumour effects. Recent studies have revealed a significant correlation between epigenetic regulatory factors and immune checkpoint therapy. Epigenetics can modulate various aspects of the tumour immune microenvironment and immune response to enhance the sensitivity of immunotherapy, such as lowering the concentration required and mitigating cytotoxicity. This review primarily discusses DNA methyltransferase inhibitors, histone deacetylase inhibitors, enhancer of zeste homolog 2 inhibitors and lysine-specific demethylase 1 inhibitors, which are associated with transcriptional repression. This repression alters the expression of genes involved in the immune checkpoint, thereby enhancing the effectiveness of immunotherapy. We also discuss the potential and challenges of tumour immunotherapy and highlight its advantages, application challenges and clinical research on integrating epigenetic regulatory factors with tumour immunotherapy.

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.

A hemoperfusion column selectively adsorbs LAP+ lymphocytes to improve anti-tumor immunity and survival of tumor-bearing rats

Reducing the number of immunosuppressive cells in blood is a potential strategy for activating anti-tumor immunity, which provides a promising approach to cancer treatment. In this study, we developed an adsorbent designed to selectively target and adsorb lymphocytes expressing latency-associated peptide (LAP), which is abundantly expressed on the surface of CD4+ regulatory T cells (Tregs) and CD14+ monocytes. We investigated whether diethylenetriamine-conjugated polysulfone adsorbent-based direct hemoperfusion (DHP) enhances anti-tumor immunity in a rat cancer model with KDH-V liver cells. Our findings revealed that DHP significantly reduced LAP+ Tregs in both peripheral blood and tumor tissues in treated mice. Consequently, cytotoxic T-lymphocytes increased in tumor-bearing rats. The anti-tumor effect was negated by the addition of cells detached from the absorbent, indicating that these cells play a crucial role in inhibiting the observed therapeutic effect. The results suggest that depleting LAP+ immunosuppressive cells in blood can enhance anti-tumor immunity and improve survival of patients.

Antibody-drug conjugates in breast cancer treatment: resistance mechanisms and the role of therapeutic sequencing

Antibody-drug conjugates (ADCs) are a transformative approach in breast cancer therapy, offering targeted treatment with reduced toxicity by selectively delivering cytotoxic agents to cancer cells. While ADCs like trastuzumab emtansine (T-DM1), trastuzumab deruxtecan (T-DXd), and sacituzumab govitecan have shown significant efficacy, resistance mechanisms such as antigen loss, impaired internalization, and efflux of cytotoxic payloads challenge their effectiveness. This review discusses these resistance mechanisms and explores advanced strategies to overcome them, including innovations in linker chemistry, multi-antigen targeting, and biomarker-driven personalization. Additionally, therapeutic sequencing - determining the optimal order of ADCs with other treatments such as chemotherapy, endocrine therapy, and immunotherapy - is examined as a crucial approach to maximize ADC efficacy and manage resistance. Evidence-based sequencing strategies, particularly for human epidermal growth factor receptor 2 (HER2)-positive and triple-negative breast cancer (TNBC), are supported by clinical trials demonstrating the benefits of ADCs in both early-stage and metastatic settings. The potential of combination therapies, such as ADCs with immune checkpoint inhibitors (ICIs), further highlights the evolving landscape of breast cancer treatment. As ADC technology advances, personalized approaches integrating biomarkers and optimized sequencing protocols offer promising avenues to enhance treatment outcomes and combat resistance in breast cancer.

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.

Investigating the Tumor-Suppressive, Antioxidant Effects and Molecular Binding Affinity of Quercetin-Loaded Selenium Nanoparticles in Breast Cancer Cells

In 2023, breast cancer is expected to have nearly 2 million new cases, making it the second most common cancer overall and the most prevalent among women. Multidrug resistance limits the effectiveness of chemotherapy; however, quercetin, a natural flavonoid, helps combat this issue. The goal of the current investigation is to determine the impact of a novel composite of quercetin and selenium nanoparticles (SeNPs) on the breast cancer cell lines MDA-MB-231 and MCF-7 in order to enhance quercetin’s tumor-suppressive action and decrease selenium (Se) toxicity. Particle size, zeta potential, FTIR, SEM, UV–VIS spectroscopy, and EDX were used to characterize quercetin-selenium nanoparticles (Que-SeNPs), in addition to evaluation of the antioxidant, apoptotic, and anticancer properties. Moreover, autophagy (Atg-13) protein receptors and PD-1/PD-L1 checkpoint were targeted using molecular docking modeling and molecular dynamics (MD) simulations to assess the interaction stability between Que-SeNPs and three targets: PDL-1, PD-1, and Atg-13HORMA domain. Que-SeNPs, synthesized with quercetin, were stable, semi-spherical (80–117 nm), and had a zeta potential of − 37.8 mV. They enhanced cytotoxicity, antioxidant activity, and apoptosis compared to quercetin alone in MCF-7 and MDA-MB-231 cells. Docking simulations showed strong binding to the PD-1/PD-L1 checkpoint and Atg-13HORMA protein receptors. Moreover, the molecular dynamics simulation revealed that the behavior of the PD-L1 intriguing insights into its structural dynamics, therefore, suggesting a stable phase where the complex is adjusting to the simulation environment. The present data confirmed that the stable formula of Que-SeNPs is cytotoxic, antioxidant, and has a potential activity to increase apoptosis in breast cancer cells, with the potential to inhibit PD-1/PD-L1 and Atg-13 proteins.

Graphical Abstract

Role of Que-SeNPs on breast cancer cells in vitro against two breast cancer cell lines MDA-MB-231 and MCF-7.

Utilizing Nanoparticles to Overcome Anti-PD-1/PD-L1 Immunotherapy Resistance in Non-Small Cell Lung cancer: A Potential Strategy

Lung cancer is the leading cause of cancer-related mortality globally, with non-small cell lung cancer (NSCLC) constituting 85% of cases. Immune checkpoint inhibitors (ICIs) represented by anti-programmed cell death protein 1 (PD-1)/ programmed cell death ligand 1 (PD-L1) have emerged as a promising frontier in cancer treatment, effectively extending the survival of patients with NSCLC. However, the efficacy of ICIs exhibits significant variability across diverse patient populations, with a substantial proportion showing poor responsiveness and acquired resistance in those initially responsive to ICIs treatments. With the advancement of nanotechnology, nanoparticles offer unique advantages in tumor immunotherapy, including high permeability and prolonged retention(EPR) effects, enhanced drug delivery and stability, and modulation of the inflammatory tumor microenvironment(TME). This review summarizes the mechanisms of resistance to ICIs in NSCLC, focusing on tumor antigens loss and defective antigen processing and presentation, failure T cell priming, impaired T cell migration and infiltration, immunosuppressive TME, and genetic mutations. Furthermore, we discuss how nanoparticles, through their intrinsic properties such as the EPR effect, active targeting effect, shielding effect, self-regulatory effect, and synergistic effect, can potentiate the efficacy of ICIs and reverse resistance. In conclusion, nanoparticles serve as a robust platform for ICIs-based NSCLC therapy, aiding in overcoming resistance challenges.

Somatostatin receptor-targeted polymeric nanoplatform for efficient CRISPR/Cas9 gene editing to enhance synergistic hepatocellular carcinoma therapy

INTRODUCTION

The CRISPR/Cas9 system-based gene therapy can fundamentally address the issues of cancer occurrence, development, progression, and metastasis. However, the lack of targeting and effectiveness hinders gene therapy from entering clinical application. Herein, a somatostatin receptor-targeted polymeric nanoplatform is developed for the delivery of a PD-L1-targeted CRISPR/Cas9 system and synergistic treatment of hepatocellular carcinoma. This nanoplatform can effectively incorporate the CRISPR/Cas9 system and the chemotherapeutic drug paclitaxel to simultaneously address the biological safety and packaging capacity issues of viral vectors. After the octreotide-modified polymer (LNA-PEG-OCT) guided the nanoparticle into hepatoma carcinoma cells, the nanoparticle protected the CRISPR/Cas9 ribonucleoprotein complex (RNP) and achieved lysosomal escape. Then, the RNP reached the target gene (PD-L1) under the guidance of the single guide RNA (sgRNA) in the RNP. The PD-L1 gene editing efficiency reached up to 55.8% for HepG2 cells in vitro and 46.0% for tumor tissues in vivo, leading to effective suppression of PD-L1 protein expression. Substantial inhibition of hepatocellular carcinoma cell proliferation and further 79.45% growth repression against subcutaneous xenograft tumors were achieved. Overall, this somatostatin receptor-targeted polymeric nanoplatform system not only provides a promising nanocarrier for CRISPR/Cas9 system delivery, but also expands the potential of combining gene editing and chemotherapy.

Exploring the application of metal-based photothermal agents in photothermal therapy combined with immune checkpoint therapy

Photothermal therapy (PTT), a popular local treatment that uses heat to ablate tumors, has limited efficacy in addressing metastatic and deeply located tumors when used alone. Integrating PTT with immunotherapy not only yields a synergistic effect but also promotes cancer regression and confers the benefit of immune memory, which can surmount the challenges faced by PTT when used in isolation. Metal-based nanomaterials, renowned for their superior photothermal conversion efficiency and distinctive photochemical properties, have been extensively researched and applied in the field of PTT. This review summarizes the latest developments in combination therapies, with a specific focus on the combination of PTT and immune checkpoint therapy (ICT) for cancer treatment, including a comprehensive overview of the recent advancements in noble metal-based and 2D transition metal chalcogenides (TMDCs)-based photothermal agents, and their anticancer effect when combining PTT with immune checkpoint blockades (anti-CTLA-4 and anti-PD-L1) therapy. The goal of this review is to present an overview of the application, current challenges and future prospects of metal-based photothermal agents in PTT combined with ICT for cancer treatment.

Spatial interaction mapping of PD-1/PD-L1 in head and neck cancer reveals the role of macrophage-tumour barriers associated with immunotherapy response

BACKGROUND

Mucosal head and neck squamous cell carcinoma (HNSCC) is often diagnosed at an advanced stage, where the prognosis is poor due to the high rates of recurrence and metastasis. With approximately one million new cases projected in 2024, worldwide mortality of HNSCC is estimated to reach 50% of detected cases the same year. Patients with early-stage tumours showed a 50-60% five-year survival rate in the US. Immune checkpoint inhibitors (ICIs) have shown promising results in prolonging survival in a subset of patients with recurrent or metastatic disease. However, challenges remain, particularly the limited efficacy of PD-1/PD-L1 blockade therapies. PD-L1 protein expression has been shown to be limited in its predictive power for ICI therapies. Emerging evidence shows that intricate characterisation of the tumour microenvironment (TME) is fundamental to understand interacting cells. This study aims to bridge the gap in understanding the tumor microenvironment by identifying distinct spatial patterns of PD-1/PD-L1 interactions and their association with immunotherapy responses in head and neck squamous cell carcinoma (HNSCC).

METHODS

In this study, we sought to apply a more nuanced approach to understanding cellular interactions by mapping PD-1/PD-L1 interactions across whole-slide HNSCC tissue samples collected prior to ICI therapy. We used a combination of spatial proteomics (Akoya Biosciences) and an in situ proximity ligation assay (isPLA, Navinci Diagnostics) to visualise PD-1/PD-L1 interactions across cell types and cellular neighbourhoods within the tumour TME.

RESULTS

Our findings indicate the existence of isPLA+ PD-1/PD-L1 interactions between macrophages/CD3 T cell-enriched neighbourhoods and tumour cells at the tumour-stroma boundaries in ICI-resistant tumours. The presence of these dense macrophage-tumour layers, which are either absent or dispersed in responders, indicates a barrier that may restrict immune cell infiltration and promote immune escape mechanisms. In contrast, responders had abundant B and T cell aggregates, predominantly around the tumour edges linked to enhanced immune responses to ICI therapy and better clinical outcomes.

CONCLUSION

This study highlights the utility of isPLA in detecting distinct tumour-immune interactions within the TME, offering new cellular interaction metrics for stratifying and optimising immunotherapy strategies.

TONSL promotes lung adenocarcinoma progression, immune escape and drug sensitivity

PURPOSE

The tonsoku-like DNA repair protein (TONSL) encoded by the TONSL gene, located on chromosome 8q24.3, is crucial for repairing DNA double-strand breaks through homologous recombination. However, TONSL overexpression in lung adenocarcinoma (LUAD) promotes tumor development, leading to a poor prognosis.

METHODS

TONSL was verified as a reliable prognostic marker for LUAD using bioinformatics, and clinical features related to LUAD prognosis were screened from the TCGA database to establish the relationship between risk factors and TONSL expression. In addition, TONSL expression in normal and LUAD tissues was verified using real-time quantitative polymerase chain reaction and immunohistochemistry. To elucidate the possible functions of TONSL, TONSL-related differentially expressed genes were screened, and functional enrichment analysis was performed. Subsequently, siRNA was used to knock down TONSL expression in lung cancer cells for cytobehavioral experiments. The effects of TONSL expression on tumor immune escape were analyzed using the ESTIMATE algorithm and tumor immune-infiltration analysis. In addition, the half-maximal inhibitory concentration of LUAD with varying TONSL expression levels in response to first-line chemotherapeutic drugs and epidermal growth factor receptor-tyrosine kinase inhibitors was analyzed for drug sensitivity.

RESULTS

Up-regulation of TONSL in LUAD promotes the proliferation, migration, and invasion of lung cancer cells, thereby contributing to a poor prognosis. Furthermore, TONSL overexpression promotes immune escape and drug sensitivity in LUAD.

CONCLUSION

TONSL serves as a reliable prognostic marker for LUAD, and its up-regulation is associated with increased immune escape and drug sensitivity. These findings suggest that TONSL holds potential as a novel therapeutic target for LUAD.

Manipulating the EphB4-ephrinB2 axis to reduce metastasis in HNSCC

The EphB4-ephrinB2 signaling axis has been heavily implicated in metastasis across numerous cancer types. Our emerging understanding of the dichotomous roles that EphB4 and ephrinB2 play in head and neck squamous cell carcinoma (HNSCC) poses a significant challenge to rational drug design. We find that EphB4 knockdown in cancer cells enhances metastasis in preclinical HNSCC models by augmenting immunosuppressive cells like T regulatory cells (Tregs) within the tumor microenvironment. EphB4 inhibition in cancer cells also amplifies their ability to metastasize through increased expression of genes associated with hallmark pathways of metastasis along with classical and non-classical epithelial-mesenchymal transition. In contrast, vascular ephrinB2 knockout coupled with radiation therapy (RT) enhances anti-tumor immunity, reduces Treg accumulation into the tumor, and decreases metastasis. Notably, targeting the EphB4-ephrinB2 signaling axis with the engineered ligands ephrinB2-Fc-His and Fc-TNYL-RAW-GS reduces local tumor growth and distant metastasis in a preclinical model of HNSCC. Our data suggests that targeted inhibition of vascular ephrinB2 while avoiding inhibition of EphB4 in cancer cells could be a promising strategy to mitigate HNSCC metastasis.

Efficacy and safety of PD-1 inhibitors as second-line treatment for advanced squamous esophageal cancer: a systematic review and network meta-analysis with a focus on PD-L1 expression levels

Background

PD-1 inhibitors have shown promising efficacy in enhancing OS and AEs as second-line therapies for patients with advanced esophageal squamous cell carcinoma (ESCC). However, there remains no clear consensus on which PD-1 inhibitor provides the best balance between efficacy and safety. To address this key issue in the second-line treatment of ESCC, we conducted a network meta-analysis (NMA) with a focus on OS benefits, particularly in patients with different levels of PD-L1 expression.

Methods

A systematic search of relevant literature was conducted in Web of Science, Embase, PubMed, and Cochrane Library, covering publications from the inception of these database to June 2024. The evaluated endpoints included OS, progression-free survival (PFS), objective response rate (ORR), AEs, and Grade ≥ 3 adverse events (Grade ≥ 3 AEs). A systematic review and Bayesian network meta-analysis were performed to assess the efficacy and safety of various immunotherapy regimens in patients with advanced ESCC. To ensure transparency, novelty, and reliability, this study was prospectively registered in the systematic review registry (CRD42024540581).

Results

Five randomized controlled trials (RCTs), encompassing 2,078 patients and six treatment regimens, were included in this study. Among advanced ESCC patients not selected based on PD-L1 expression, Sintilimab demonstrated the greatest OS benefit (HR = 0.70, 95% CI: 0.50-0.98). Camrelizumab showed the most favorable improvement in PFS compared to chemotherapy (HR = 0.64, 95% CI: 0.47-0.87) and also achieved the best ORR benefit (OR = 3.72, 95% CI: 1.98-6.99). In terms of safety, Nivolumab (OR = 0.10, 95% CI: 0.05-0.19) and Tislelizumab (OR = 0.18, 95% CI: 0.10-0.33) exhibited significant safety advantages over chemotherapy concerning AEs. Moreover, Nivolumab (OR = 0.13, 95% CI: 0.08-0.20) was associated with a markedly lower risk of Grade ≥ 3 AEs compared to chemotherapy. Subgroup analysis based on PD-L1 expression revealed that Tislelizumab (HR = 0.53, 95% CI: 0.37-0.76) offered the greatest OS benefit for patients with PD-L1 ≥ 10%, while Camrelizumab (HR = 0.71, 95% CI: 0.57-0.89) was the most likely regimen to provide an OS advantage for patients with PD-L1 < 10%.

Conclusion

Compared to chemotherapy, PD-1 inhibitors may provide improved survival outcomes for patients with advanced ESCC. Among patients not selected based on PD-L1 expression, Sintilimab is most likely to deliver the best survival benefit. For patients with PD-L1 expression ≥ 10%, Tislelizumab is expected to offer the greatest efficacy, while Camrelizumab appears to be the most effective for those with PD-L1 < 10%.

Systematic Review Registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42024540581.

Innovative CDR grafting and computational methods for PD-1 specific nanobody design

Introduction

The development of nanobodies targeting Programmed Cell Death Protein-1 (PD-1) offers a promising approach in cancer immunotherapy. This study aims to design and characterize a PD-1-specific nanobody using an integrated computational and experimental approach.

Methods

An in silico design strategy was employed, involving Complementarity-Determining Region (CDR) grafting to construct the nanobody sequence. The three-dimensional structure of the nanobody was predicted using AlphaFold2, and molecular docking simulations via ClusPro were conducted to evaluate binding interactions with PD-1. Physicochemical properties, including stability and solubility, were analyzed using web-based tools, while molecular dynamics (MD) simulations assessed stability under physiological conditions. The nanobody was produced and purified using Ni-NTA chromatography, and experimental validation was performed through Western blotting, ELISA, and dot blot analysis.

Results

Computational findings demonstrated favorable binding interactions, stability, and physicochemical properties of the nanobody. Experimental results confirmed the nanobody's specific binding affinity to PD-1, with ELISA and dot blot analyses providing evidence of robust interaction.

Discussion

This study highlights the potential of combining computational and experimental approaches for engineering nanobodies. The engineered PD-1 nanobody exhibits promising characteristics, making it a strong candidate for further testing in cancer immunotherapy applications.

Helicobacter pylori CagA promotes gastric cancer immune escape by upregulating SQLE

Helicobacter pylori (H. pylori) infection is a well-established risk factor for gastric cancer, primarily due to its virulence factor, cytotoxin-associated gene A (CagA). Although PD-L1/PD-1-mediated immune evasion is critical in cancer development, the impact of CagA on PD-L1 regulation remains unclear. This study revealed that H. pylori CagA upregulated squalene epoxidase (SQLE) expression, a key enzyme in the cholesterol biosynthesis pathway. Elevated SQLE activity increased cellular palmitoyl-CoA levels, enhancing PD-L1 palmitoylation while decreasing its ubiquitination. This ultimately increases PD-L1 stability, suppressing T cell activity and facilitating immune evasion in gastric cancer. In summary, our findings highlight the crucial role of the CagA-SQLE-PD-L1 axis in gastric cancer progression, suggesting potential therapeutic strategies for targeting CagA-positive gastric cancer.

Exosomal miR-142-3p from M1-polarized macrophages suppresses cell growth and immune escape in glioblastoma through regulating HMGB1-mediated PD-1/PD-L1 checkpoint

Glioblastoma (GBM) is one of the most prevalent cancerous brain tumors. Former studies have reported that exosomes derived from M1-polarized macrophages (M1 exosomes) inhibit tumor occurrence and development through delivery of tumor suppressor genes. Also, microRNA-142-3p (miR-142-3p) has been verified to function as a tumor suppressor. GBM cell proliferation was evaluated by Cell Counting Kit-8 (CCK-8), colony formation assay and 5-ethynyl-2'-deoxyuridine (EdU) assay; cell apoptosis was determined by flow cytometry analysis and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Mechanism investigations were conducted for analyzing the molecular mechanism by which miR-142-3p and M1 exosomes affect GBM progression. Upregulation of miR-142-3p expression was detected in M1-polarized macrophages and M1 exosomes. M1 exosomes inhibit GBM cell proliferation and trigger cell apoptosis. Functionally, miR-142-3p silencing promotes the proliferation and inhibits the apoptosis of GBM cells treated with M1 exosomes. As for molecular mechanism, miR-142-3p inhibits GBM cell growth via targeting high-mobility group box 1 (HMGB1). In addition, miR-142-3p/HMGB1 axis affects GBM cell immune escape through modulation of programmed death-1/programmed death ligand-1 (PD-1/PD-L1) checkpoint. Our study demonstrated that exosomal miR-142-3p from M1-polarized macrophages suppresses cell growth and immune escape in GBM through regulating HMGB1-mediated PD-1/PD-L1 checkpoint.

Shifting cold to hot tumors by nanoparticle-loaded drugs and products

Cold tumors lack antitumor immunity and are resistant to therapy, representing a major challenge in cancer medicine. Because of the immunosuppressive spirit of the tumor microenvironment (TME), this form of tumor has a low response to immunotherapy, radiotherapy, and also chemotherapy. Cold tumors have low infiltration of immune cells and a high expression of co-inhibitory molecules, such as immune checkpoints and immunosuppressive molecules. Therefore, targeting TME and remodeling immunity in cold tumors can improve the chance of tumor repression after therapy. However, tumor stroma prevents the infiltration of inflammatory cells and hinders the penetration of diverse molecules and drugs. Nanoparticles are an intriguing tool for the delivery of immune modulatory agents and shifting cold to hot tumors. In this review article, we discuss the mechanisms underlying the ability of nanoparticles loaded with different drugs and products to modulate TME and enhance immune cell infiltration. We also focus on newest progresses in the design and development of nanoparticle-based strategies for changing cold to hot tumors. These include the use of nanoparticles for targeted delivery of immunomodulatory agents, such as cytokines, small molecules, and checkpoint inhibitors, and for co-delivery of chemotherapy drugs and immunomodulatory agents. Furthermore, we discuss the potential of nanoparticles for enhancing the efficacy of cancer vaccines and cell therapy for overcoming resistance to treatment.

Efficacy and Safety of Paclitaxel-Based PD-1/PD-L1 Immunotherapies for Triple-Negative Breast Cancer: A Systematic Review and Network Meta-Analysis

Background

Triple negative breast cancer (TNBC) is a deadly subtype of breast cancer with limited treatment options. Currently, programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors have become the first choice for breast cancer immunotherapies. Despite paclitaxel being considered a cornerstone drug in breast cancer treatment, the effectiveness, safety, and optimal drug selection for its combination with PD-1/PD-L1 inhibitors remain uncertain.

Methods

We conducted a systematic review and network meta-analysis, performing a comprehensive literature search across PubMed, Embase, and the Cochrane Library from the inception of each database through May 18, 2024. Selected trials were those that assessed the efficacy and safety of paclitaxel-based PD-1/PD-L1 therapies for the treatment of TNBC. The primary endpoint assessed was overall survival (OS), while secondary outcomes included progression-free survival (PFS), adverse events (AEs), overall response rate (ORR), and Pathological complete response (pCR). This study is registered in PROSPERO under registration number CRD42023429651.

Results

A total of 8 RCTs meeting our eligibility criteria were included, involving 4626 patients who received either Paclitaxel (Paclitaxel-placebo/chemotherapy) or a combination of durvalumab, pembrolizumab, atezolizumab, toripalimab with paclitaxel. The pooled results demonstrated that Durvalumab combined with Paclitaxel significantly reduced the hazard ratio for OS (surface under the cumulative ranking [SUCRA]: 91.05%) and PFS compared with Paclitaxel alone (SUCRA: 83.52%). Additionally, Durvalumab plus Paclitaxel significantly improved the ORR compared with Paclitaxel (odds ratio [OR]: 2.30; 95% credible interval [CrI]: 1.10-5.20). For safety outcomes, Atezolizumab plus Paclitaxel showed a favorable profile in AEs, with no significant differences observed between groups. In the pCR study, Pembrolizumab plus Paclitaxel was the most effective treatment option (SUCRA: 81.85%).

Conclusions

When combined with paclitaxel, PD-1/PD-L1 inhibitors exhibit a favorable survival benefit. The combination of Durvalumab and paclitaxel represents the optimal treatment option. In the future, attention should be paid to the TNBC subtypes and drug dosage, as these factors may help to design personalized TNBC treatment programs.

Role of PD-1/PD-L1 signaling axis in oncogenesis and its targeting by bioactive natural compounds for cancer immunotherapy

Cancer is a global health problem and one of the leading causes of mortality. Immune checkpoint inhibitors have revolutionized the field of oncology, emerging as a powerful treatment strategy. A key pathway that has garnered considerable attention is programmed cell death-1 (PD-1)/programmed cell death ligand-1 (PD-L1). The interaction between PD-L1 expressed on tumor cells and PD-1 reduces the innate immune response and thus compromises the capability of the body's immune system. Furthermore, it controls the phenotype and functionality of innate and adaptive immune components. A range of monoclonal antibodies, including avelumab, atezolizumab, camrelizumab, dostarlimab, durvalumab, sinitilimab, toripalimab, and zimberelimab, have been developed for targeting the interaction between PD-1 and PD-L1. These agents can induce a broad spectrum of autoimmune-like complications that may affect any organ system. Recent studies have focused on the effect of various natural compounds that inhibit immune checkpoints. This could contribute to the existing arsenal of anticancer drugs. Several bioactive natural agents have been shown to affect the PD-1/PD-L1 signaling axis, promoting tumor cell apoptosis, influencing cell proliferation, and eventually leading to tumor cell death and inhibiting cancer progression. However, there is a substantial knowledge gap regarding the role of different natural compounds targeting PD-1 in the context of cancer. Hence, this review aims to provide a common connection between PD-1/PD-L1 blockade and the anticancer effects of distinct natural molecules. Moreover, the primary focus will be on the underlying mechanism of action as well as the clinical efficacy of bioactive molecules. Current challenges along with the scope of future research directions targeting PD-1/PD-L1 interactions through natural substances are also discussed.

Efficacy and safety of PD-1 and PD-L1 inhibitors in advanced colorectal cancer: a meta-analysis of randomized controlled trials

BACKGROUND

PD-1 and PD-L1 inhibitors have emerged as promising therapies for advanced colorectal cancer (CRC), but their efficacy and safety profiles require further evaluation. This meta-analysis aims to assess the efficacy and safety of PD-1/PD-L1 inhibitors in this patient population.

METHODS

A systematic review and meta-analysis were conducted following PRISMA guidelines, with data sourced from PubMed, Embase, CENTRAL, Web of Science, and CNKI up to August 3, 2024. Nine randomized controlled trials (RCTs) involving 1680 patients were included. The primary outcomes were overall survival (OS), progression-free survival (PFS) and objective response rate (ORR), while safety was assessed through adverse events (AEs) and grade ≥ 3 AEs. Effect sizes were calculated using mean differences (MD) and risk ratios (RR) with 95% confidence intervals (CIs).

RESULTS

Overall, the meta-analysis showed that PD-1/PD-L1 inhibitors did not significantly extend OS (MD = 0.86, 95% CI: -0.55, 2.27), but they significantly improved PFS (MD = 2.53, 95% CI: 0.92, 4.15). Additionally, PD-1/PD-L1 inhibitors did not significantly increase the ORR compared to controls (RR = 1.19, 95% CI: 0.99, 1.44). In terms of safety, PD-1/PD-L1 inhibitors did not significantly increase the incidence of overall AEs. Subgroup analysis further indicated that PD-1 inhibitors significantly improved OS (MD = 1.24, 95% CI: 0.20, 2.29) and PFS (MD = 6.27, 95% CI: 0.56, 11.97), while PD-L1 inhibitors did not have a significant impact on these outcomes. Additionally, PD-L1 inhibitors were associated with a higher risk of grade ≥ 3 AEs (RR = 1.29, 95% CI: 1.07, 1.57), a risk not observed with PD-1 inhibitors.

CONCLUSION

PD-1 inhibitors significantly improve PFS and OS in advanced CRC, making them a preferable option over PD-L1 inhibitors, which show limited efficacy and a higher risk of severe AEs. These findings support prioritizing PD-1 inhibitors in clinical practice for this patient group, while caution is warranted with PD-L1 inhibitors due to their safety concerns.

TRIAL REGISTRATION

PROSPERO (CRD42024611696).

99mTc(I)-Labeled His-Tagged Proteins: Impact in the Development of Novel Imaging Probes and in Drug Discovery

Technetium-99 m (99mTc) remains the cornerstone of nuclear medicine for single photon emission computed tomography (SPECT) due to its widespread availability and chemical and physical features. Its multiple oxidation states allow for the design and production of radiopharmaceuticals with versatile properties, namely in terms of pharmacokinetic profile. 99mTc(V) is the most common oxidation state, but 99mTc(I) gained traction after the pioneering work of Alberto and colleagues, which resulted in the introduction of the organometallic core fac-[99mTc(CO)3(H2O)3]+. This core is readily available from [99mTcO4]- and displays three labile water molecules that can be easily swapped for ligands with different denticity and/or donor atoms in aqueous environment. This makes it possible to radiolabel small molecules as well as high molecular weight molecules, such as antibodies or other proteins, while assuring biological activity. Direct radiolabelling of those proteins with fac-[99mTc(CO)3]+ under mild conditions is accomplished through incorporation of a polyhistidine tag (His-tag), a commonly used tag for purification of recombinant proteins. This review aims to address the direct radiolabelling of His-tagged macromolecules with fac-[99mTc(CO)3]+ for development of molecular imaging agents and the impact of this technology in the discovery and development of imaging and/or therapeutic agents towards clinical application.

Hydrogel systems for spatiotemporal controlled delivery of immunomodulators: engineering the tumor immune microenvironment for enhanced cancer immunotherapy

Tumor immunotherapy, modulating innate and adaptive immunity, has become an important therapeutic strategy. However, the tumor immune microenvironment's (TIME) complexity and heterogeneity challenge tumor immunotherapy. Hydrogel is a hydrophilic three-dimensional (3D) mesh structure with good biocompatibility and drug release control, which is widely used in drug delivery, agriculture, industry, etc. Hydrogels loaded with immune cells, cytokines, immune checkpoint inhibitors, and anti-tumor drugs can achieve targeted delivery and ultimately activate the immune response in the TIME. In this review, we will summarize the components of the TIME and their immune effects, the emerging immunomodulatory agents, the characteristics and functions of hydrogels, and how hydrogels regulate innate and adaptive immune cells in the TIME.

Prognostic significance of combined PD-L1 expression in malignant and infiltrating cells in hepatocellular carcinoma treated with atezolizumab and bevacizumab

Background

Programmed death-ligand 1 (PD-L1) expression is abundant not only in malignant cells but also in infiltrating cells within the tumor microenvironment (TME) of hepatocellular carcinoma (HCC). This study explored the association between PD-L1 expression in TME and outcomes in HCC patients treated with atezolizumab plus bevacizumab (AB), emphasizing the implications of PD-L1 expression in both malignant and tumor-infiltrating cells.

Methods

This study included 72 patients with HCC who underwent percutaneous core needle liver biopsy before AB treatment between September 2020 and December 2023. PD-L1 expression on tumor tissues was assessed using the combined positive score (CPS) with cutoff values of 1 and 10, utilizing antibody clone 22C3 (Dako).

Results

The distribution of PD-L1 CPS included 24 patients with CPS <1, 33 patients with CPS 1-10, and 15 patients with CPS ≥10. Significant differences in overall survival (OS) were observed across the three groups, with CPS ≥10 showing the highest survival rates (p = 0.010). Patients with CPS ≥10 had better OS than those with CPS <10 (median OS 14.8 vs. 8.3 months, P = 0.046), and CPS ≥1 had better OS than CPS <1 (P = 0.021). For progression-free survival (mPFS), the CPS ≥10 group had the highest median PFS of 11.0 months among the three groups (P = 0.044). Objective response rates (ORR) were higher in the PD-L1 CPS ≥10 group than in the 1-10 and <1 group (53.3%, 27.3%, and 16.7%, respectively; P = .047). Multivariate analysis identified that PD-L1 expression ≥10 and ≥1 were associated with favorable outcomes regarding OS (hazard ratio [HR] 0.283, P = .027 and HR 0.303, P = .006, respectively).

Conclusions

Combined analysis of PD-L1 expression in malignant and tumor-infiltrating cells can be a promising biomarker for the prognosis of HCC patients treated with AB.

Akkermansia muciniphila- and Pathogenic Bacteria-Derived Endotoxins Differently Regulate Human Dendritic Cell Generation and γδ T Lymphocyte Activation

Lipopolysaccharide (LPS) is a potent endotoxin released at high concentrations in acute infections, causing massive host inflammatory response. Accumulating evidence indicates that dysbiosis-associated chronic low levels of circulating LPS can sustain a prolonged sterile low-grade inflammation that increases the risk of several non-communicable diseases. Interventions aimed at increasing the abundance of beneficial/probiotic bacteria, including Akkermansia muciniphila, result in reduced inflammation, favoring metabolic and immune health. Immunosuppression is a common feature in conditions of chronic inflammation, and dendritic cells (DCs) represent key targets given their ability to shift the balance toward immunity or tolerance. In this study, the effects of low concentrations of LPS from pathogenic (Escherichia coli and Salmonella enterica) and probiotic (Akkermansia muciniphila) bacterial species on human DC generation and functions were compared. We report that monocyte precursor priming with Escherichia coli and Salmonella enterica LPS forces the differentiation of PD-L1-expressing DCs, releasing high levels of IL-6 and IL-10, and impairs their capacity to drive full TCR-Vδ2 T cell activation. Conversely, comparable concentrations of Akkermansia muciniphila promoted the generation of DCs with preserved activating potential and immunostimulatory properties. These results shed light on potential mechanisms underlying the impact of low endotoxemia on disease risk and pathogenesis, and increase our understanding of the immunomodulatory effects of Akkermansia muciniphila.

Comparison of the efficacy and safety of perioperative immunochemotherapeutic strategies for locally advanced esophageal cancer: a systematic review and network meta-analysis

Background

The aim of this network meta-analysis was to clarify the efficacy and safety of different immune checkpoint inhibitors (ICIs) in combination with chemotherapy in the neoadjuvant phase for the treatment of locally advanced esophageal cancer.

Methods

We searched PubMed, EMBASE, Web of Science, Cochrane Library, CNKI and WanFang databases from January 2000 until May 2024. The primary endpoints were pathological complete response (pCR), major pathological response (MPR), R0 resection rate, objective response rate (ORR), disease control rate (DCR), treatment-related adverse events(TRAEs) of any grade and TRAEs of grade 3 or higher. The Newcastle-Ottawa Scale (NOS) and the Cochrane Risk of Bias tool were used to evaluate risk of bias. To analyze the data, Review Manager 5.3 and Stata16.0 were applied.

Results

Fourteen eligible studies (six randomized controlled trials) and 8 retrospective cohort studies) enrolling 1139 patients were included for this network meta-analysis. All studies originated from China. For patients with locally advanced esophageal cancer, neoadjuvant immunochemotherapeutic strategies showed significant advantages over traditional neoadjuvant therapy in terms of pCR, MPR, ORR and DCR. Among the analyzed regimens, camrelizumab plus chemotherapy demonstrated the most pronounced improvements in pCR and MPR, while pembrolizumab plus chemotherapy achieved the best outcomes in terms of ORR and DCR. There were no significant differences observed among the various neoadjuvant treatment strategies regarding R0 resection rate, any grade TRAEs, or grade≥3 TRAEs. The most common TRAEs in the neoadjuvant chemotherapy plus immunotherapy group were myelosuppression and gastrointestinal damage, with most grade 3 or higher TRAEs being hematologic adverse events. The most frequent immune-related adverse events(irAEs) included rash (4.2-21.7%), thyroid dysfunction (hypothyroidism or hyperthyroidism, 6.3-17.4%), and pneumonia (4.2-6.3%), with the majority being mild to moderate (grade 1 or 2).

Conclusions

Neoadjuvant immunotherapy combined with chemotherapy regimens demonstrate relatively high efficacy and tolerable safety profiles. Among the evaluated regimens, the combination chemotherapy with camrelizumab had relatively high pCR and MPR, whereas the combination chemotherapy with pembrolizumab had relatively high ORR and DCR. There were no significant differences in safety among the various regimens. Our study suggests that evaluating the efficacy and safety of different ICIs may be helpful in clinical decision-making.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024583548.

Structural basis for the synergetic neutralization of hepatitis E virus by antibody-antibody interaction

Neutralizing antibodies (nAbs) play a crucial role in virology, antibody drug development, and vaccine research. In this study, we investigated the synergistic effect of two hepatitis E virus (HEV) nAbs, 8H3, and 8C11, which have exhibited enhanced neutralizing activity in a rhesus monkey model. We presented crystal structures of 8H3 Fab alone and a triple complex of 8C11 Fab and 8H3 Fab simultaneously binding to the HEV E2s protein (8C11:E2s:8H3). Through structural analysis, we identified critical binding sites and fully elucidated the binding footprints of nAb 8H3 in the 8C11:E2s:8H3 complex using site-directed mutagenesis, pinpointing Ile 529, Glu 549, Lys 554, and Ser 566 in the E2s domain, and K66H, S67H, D88H in the 8C11 heavy chain. Interestingly, the synergetic enhancement of 8C11 to 8H3 converted to an antagonistic effect when 8C11 bound to E2s with pretreatment of 8H3, indicating a unidirectional synergistic effect associated with the sequence of antibody involvement. We demonstrated this phenomenon through structural comparisons of E2s:8C11 vs. 8C11:E2s:8H3 crystal structures and molecular dynamics simulations, found that Ile 529 played a key role in the synergistic interplay between these two nAbs. The two-antibody combination showed a more potent antibody-imposed physical disruption mechanism and enhanced coneutralization in an authentic HEV-based cell model. Our study suggests a strategy for synergistic antibody cocktail design with antibody-antibody side-by-side interaction.

Immunoproteasome Activation Expands the MHC Class I Immunopeptidome, Unmasks Neoantigens, and Enhances T-cell Anti-Myeloma Activity

Proteasomes generate antigenic peptides that are presented on the tumor surface to cytotoxic T-lymphocytes. Immunoproteasomes are highly specialized proteasome variants that are expressed at higher levels in antigen-presenting cells and contain replacements of the three constitutive proteasome catalytic subunits to generate peptides with a hydrophobic C-terminus that fit within the groove of MHC class I (MHC-I) molecules. A hallmark of cancer is the ability to evade immunosurveillance by disrupting the antigen presentation machinery and downregulating MHC-I antigen presentation. High-throughput screening was performed to identify compound A, a novel molecule that selectively increased immunoproteasome activity and expanded the number and diversity of MHC-I-bound peptides presented on multiple myeloma cells. Compound A increased the presentation of individual MHC-I-bound peptides by >100-fold and unmasked tumor-specific neoantigens on myeloma cells. Global proteomic integral stability assays determined that compound A binds to the proteasome structural subunit PSMA1 and promotes association of the proteasome activator PA28α/β (PSME1/PSME2) with immunoproteasomes. CRISPR/Cas9 silencing of PSMA1, PSME1, or PSME2 as well as treatment with immunoproteasome-specific suicide inhibitors abolished the effects of compound A on antigen presentation. Treatment of multiple myeloma cell lines and patient bone marrow-derived CD138+ cells with compound A increased the anti-myeloma activity of allogenic and autologous T cells. Compound A was well-tolerated in vivo and co-treatment with allogeneic T cells reduced the growth of myeloma xenotransplants in NOD/SCID gamma mice. Taken together, our results demonstrate the paradigm shifting impact of immunoproteasome activators to diversify the antigenic landscape, expand the immunopeptidome, potentiate T-cell-directed therapy, and reveal actionable neoantigens for personalized T-cell immunotherapy.

S-acylation of Ca2+ transport proteins in cancer

Alterations in cellular calcium (Ca2+) signals have been causally associated with the development and progression of human cancers. Cellular Ca2+ signals are generated by channels, pumps, and exchangers that move Ca2+ ions across membranes and are decoded by effector proteins in the cytosol or in organelles. S-acylation, the reversible addition of 16-carbon fatty acids to proteins, modulates the activity of Ca2+ transporters by altering their affinity for lipids, and enzymes mediating this reversible post-translational modification have also been linked to several types of cancers. Here, we compile studies reporting an association between Ca2+ transporters or S-acylation enzymes with specific cancers, as well as studies reporting or predicting the S-acylation of Ca2+ transporters. We then discuss the potential role of S-acylation in the oncogenic potential of a subset of Ca2+ transport proteins involved in cancer.

Immune Checkpoints in B Cells: Unlocking New Potentials in Cancer Treatment

B cells are crucial component of humoral immunity, and their role in the tumor immune microenvironment (TME) has garnered significant attention in recent years. These cells hold great potential and application prospects in the field of tumor immunotherapy. Research has demonstrated that the TME can remodel various B cell functions, including proliferation, differentiation, antigen presentation, and antibody production, thereby invalidating the anti-tumor effects of B cells. Concurrently, numerous immune checkpoints (ICs) on the surface of B cells are upregulated. Aberrant B-cell IC signals not only impair the function of B cells themselves, but also modulate the tumor-killing effects of other immune cells, ultimately fostering an immunosuppressive TME and facilitating tumor immune escape. Blocking ICs on B cells is beneficial for reversing the immunosuppressive TME and restoring anti-tumor immune responses. In this paper, the intricate connection between B-cell ICs and the TME is delved into, emphasizing the critical role of targeting B-cell ICs in anti-tumor immunity, which may provide valuable insights for the future development of tumor immunotherapy based on B cells.

Deubiquitinases as novel therapeutic targets for diseases

Deubiquitinating enzymes (DUBs) regulate substrate ubiquitination by removing ubiquitin or cleaving within ubiquitin chains, thereby maintaining cellular homeostasis. Approximately 100 DUBs in humans counteract E3 ubiquitin ligases, finely balancing ubiquitination and deubiquitination processes to maintain cellular proteostasis and respond to various stimuli and stresses. Given their role in modulating ubiquitination levels of various substrates, DUBs are increasingly linked to human health and disease. Here, we review the DUB family, highlighting their distinctive structural characteristics and chain-type specificities. We show that DUB family members regulate key signaling pathways, such as NF-κB, PI3K/Akt/mTOR, and MAPK, and play crucial roles in tumorigenesis and other diseases (neurodegenerative disorders, cardiovascular diseases, inflammatory disorders, and developmental diseases), making them promising therapeutic targets Our review also discusses the challenges in developing DUB inhibitors and underscores the critical role of the DUBs in cellular signaling and cancer. This comprehensive analysis enhances our understanding of the complex biological functions of the DUBs and underscores their therapeutic potential.

Into the Future: Fighting Melanoma with Immunity

Immunotherapy offers a novel and promising option in the treatment of late-stage melanoma. By utilizing the immune system to assist in tumor destruction, patients have additional options after tumor progression. Immune checkpoint inhibitors reduce the ability for tumors to evade the immune system by inhibiting key surface proteins used to inactivate T-cells. Without these surface proteins, T-cells can induce cytotoxic responses against tumors. Tumor infiltrating lymphocyte therapy is a form of adoptive cell therapy that takes advantage of a small subset of T-cells that recognize and infiltrate tumors. Isolation and rapid expansion of these colonies assist the immune system in mounting a charged response that can induce remission. Tumor vaccines deliver a high dose of unique antigens expressed by tumor cells to the entire body. The introduction of large quantities of tumor antigens upregulates antigen presenting cells and leads to effective activation of the immune system against tumors. Cytokine therapy introduces high amounts of chemical messengers that are endogenous to the immune system and support T-cell expansion. While other methods of immunotherapy exist, immune checkpoint inhibitors, tumor infiltrating lymphocytes, tumor vaccines, and cytokine therapy are commonly used to treat melanoma. Like many other cancer treatments, immunotherapy is not without adverse effects, as toxicities represent a major obstacle. However, immunotherapy has been efficacious in the treatment of melanoma.

Microsatellite Instability in Urine: Breakthrough Method for Bladder Cancer Identification

Bladder cancer (BC) is the most common neoplasm of the urinary system and ranks tenth in global cancer incidence. Due to its high recurrence rate and the need for continuous monitoring, it is the cancer with the highest cost per patient. Cystoscopy is the traditional method for its detection and surveillance; however, this is an invasive technique, while non-invasive methods, such as cytology, have a limited sensitivity. For this reason, new non-invasive strategies have emerged, analyzing useful markers for BC detection from urine samples. The identification of tumor markers is essential for early cancer detection and treatment. Urine analysis offers a non-invasive method to identify these markers. Microsatellite instability (MSI) has been proposed as a promising marker for tumor cell detection and guided targeted therapies. Therefore, this review aims to explore the evidence supporting the identification of MSI in exfoliated bladder tumor cells (EBTCs) in the urine, emphasizing its potential as a non-invasive and clinically effective alternative for tumor identification. Furthermore, establishing clinical guidelines is crucial for standardizing its application in oncological screening and validating its clinical utility.

Advances in Immunotherapy for Endometrial Cancer: Insights into MMR Status and Tumor Microenvironment

Endometrial cancer is one of the most common gynecological malignancies, and while early-stage cases are highly treatable, recurrent or advanced EC remains challenging to manage. Immunotherapy, particularly immune checkpoint inhibitors, has revolutionized treatment approaches in oncology, and its application in EC has shown promising results. Key to immunotherapy efficacy in EC is the tumor's mismatch repair status, with MMR-deficient tumors demonstrating a higher tumor mutational burden and increased PD-L1 expression, making them more susceptible to immune checkpoint inhibitors (ICIs) such as pembrolizumab, durvalumab, and dostarlimab. However, not all mismatch repair-deficient (MMRd) tumors respond to ICIs, particularly those with a "cold" tumor microenvironment (TME) characterized by poor immune infiltration. In contrast, some MMR-proficient tumors with a "hot" TME respond well to ICIs, underscoring the complex interplay between MMR status, tumor mutational burden (TMB), and TME. To overcome resistance in cold tumors, novel therapies, including Chimeric Antigen Receptor (CAR) T cells and tumor-infiltrating lymphocytes are being explored, offering targeted immune-based strategies to enhance treatment efficacy. This review discusses the current understanding of immunotherapy in EC, emphasizing the prognostic and therapeutic implications of MMR status, TME composition, and emerging cell-based therapies.

From regulation to deregulation of p53 in hematologic malignancies: implications for diagnosis, prognosis and therapy

The p53 protein, encoded by the TP53 gene, serves as a critical tumor suppressor, playing a vital role in maintaining genomic stability and regulating cellular responses to stress. Dysregulation of p53 is frequently observed in hematological malignancies, significantly impacting disease progression and patient outcomes. This review aims to examine the regulatory mechanisms of p53, the implications of TP53 mutations in various hematological cancers, and emerging therapeutic strategies targeting p53. We conducted a comprehensive literature review to synthesize recent findings related to p53's multifaceted role in hematologic cancers, focusing on its regulatory pathways and therapeutic potential. TP53 mutations in hematological malignancies often lead to treatment resistance and poor prognosis. Current therapeutic strategies, including p53 reactivation and gene therapy, show promise in improving treatment outcomes. Understanding the intricacies of p53 regulation and the consequences of its mutations is essential for developing effective diagnostic and therapeutic strategies in hematological malignancies, ultimately enhancing patient care and survival.

Computational identification of PDL1 inhibitors and their cytotoxic effects with silver and gold nanoparticles

Immunotherapy is a promising treatment for cancer that aims to boost the immune system's response to cancer cells. This can be achieved by blocking Programmed cell death protein 1/Programmed death-ligand 1 (PD1/PDL1), which activates T cells. In this work, the aim was to find high-affinity drugs against PDL1 using computational tools and conjugate nanoparticles with them. The cytotoxic activity of the nanoparticle conjugated drugs was then tested. The screening of 100,000 drugs from the ZINC database and FDA-approved drugs was done computationally. The physicochemical properties and toxicity of the drugs were analyzed using SwissADME and ProTox-II, respectively. Silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) were synthesized using extracts of Catharanthus roseus flowers and Juglans regia shells, respectively. The characterization of AgNPs and AuNPs was performed using UV-Vis spectroscopy, X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Their conjugation with the drugs Irinotecan, Imatinib, and Methotrexate was also confirmed using UV-Vis, FTIR, and Dynamic light scattering (DLS). The top screened drugs were ZINC1098661 and 3 FDA-approved drugs (Irinotecan, Imatinib, and Methotrexate). Docking studies revealed that Irinotecan had the highest binding affinity towards PDL1 when conjugated with silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs). The Irinotecan-PDL1 complex was confirmed as the most stable through molecular dynamics simulations. The result of the methylthiazol tetrazolium (MTT) assay showed that conjugated AgNPs and AuNPs with Irinotecan had a higher toxic effect on the A549 cancer cell line than AgNPs and AuNPs conjugated with Imatinib. This study provides a promising avenue for further investigation and development of nanoparticle-drug conjugates as a potential cancer immunotherapy strategy.

Current and Future Perspectives of PDL1 PET and SPECT Imaging

Programmed Death 1 (PD1) and Programmed Death Ligand (PDL1) play a crucial role in tumor microenvironment by helping cancer cells evade innate immunity. Numerous inhibitor anticancer drugs targeting this interplay have been used in clinical practice and many more are in preclinical stage. These drugs have shown promising results in achieving good response and long-term clinical benefit, is routinely performed to identify patients who may benefit. However, there are major challenges associated with these immunohistochemistry tests which have opened the space for noninvasive imaging modalities using PD1 and PDL1 inhibitors labeled with either PET or SPECT radionuclides. These radiopharmaceuticals, although primarily developed for the field of immunotherapy, have great potential in expanding and optimizing the combination of radiopharmaceutical therapies with PD1-PDL1 targeting anticancer drugs. This review elaborates currently available PET and SPECT radiopharmaceuticals targeting PD1-PDL1 axis. It also explores the potential future role of newer targets which are being developed and tested in various preclinical studies.

CRISPR/Cas9-mediated knockout strategies for enhancing immunotherapy in breast cancer

Breast cancer, a prevalent disease with significant mortality rates, often presents treatment challenges due to its complex genetic makeup. This review explores the potential of combining Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) gene knockout strategies with immunotherapeutic approaches to enhance breast cancer treatment. The CRISPR/Cas9 system, renowned for its precision in inducing genetic alterations, can target and eliminate specific cancer cells, thereby minimizing off-target effects. Concurrently, immunotherapy, which leverages the immune system's power to combat cancer, has shown promise in treating breast cancer. By integrating these two strategies, we can potentially augment the effectiveness of immunotherapies by knocking out genes that enable cancer cells to evade the immune system. However, safety considerations, such as off-target effects and immune responses, necessitate careful evaluation. Current research endeavors aim to optimize these strategies and ascertain the most effective methods to stimulate the immune response. This review provides novel insights into the integration of CRISPR/Cas9-mediated knockout strategies and immunotherapy, a promising avenue that could revolutionize breast cancer treatment as our understanding of the immune system's interplay with cancer deepens.

Advances in immunotherapy for hepatitis B virus associated hepatocellular carcinoma patients

Hepatitis B virus (HBV) infection plays an important role in the occurrence and development of hepatocellular carcinoma (HCC), and the rate of HBV infection in liver cancer patients in China is as high as 92.05%. Due to long-term exposure to chronic antigens from the gut, the liver needs to maintain a certain level of immune tolerance, both to avoid severe inflammation caused by non-pathogenic antigens and to maintain the possibility of rapid and violent responses to infection and tumors. Therefore, HBV infection interacts with the tumor microenvironment (TME) through a highly complex and intertwined signaling pathway, which results in a special TME in HCC. Due to changes in the TME, tumor cells can evade immune surveillance by inhibiting tumor-specific T cell function through cytotoxic T-lymphocy-associated protein-4 (CTLA-4) and programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1). Interferons, as a class of immune factors with strong biological activity, can improve the TME of HBV-HCC through various pathways. In recent years, the systematic treatment of HCC has gradually come out of the dilemma. In addition to the continuous emergence of new multi-target anti-vascular tyrosine kinase inhibitor drugs, immune checkpoint inhibitors have opened up a new avenue for the systematic treatment of HCC. At present, immunotherapy based on PD-1/L1 inhibitors has gradually become a new direction of systematic treatment for HCC, and the disease characteristics of patients included in global clinical studies are different from those of Chinese patients. Therefore, whether a group of HCC patients with HBV background and poor prognosis in China can also benefit from immunotherapy is an issue of wide concern. This review aims to elucidate the advances of immunotherapy for HBV related HCC patients with regard to: (1) Immunotherapy based on interferons; (2) Immunotherapy based on PD-1/L1 inhibitors; (3) Immunotherapy based on CTLA4 inhibitors; (4) Adoptive cell transfer; (5) Combination immunotherapy strategy; and (6) Shortcomings of immunotherapy.

Advances in immunotherapy for hepatitis B virus associated hepatocellular carcinoma patients

Hepatitis B virus (HBV) infection plays an important role in the occurrence and development of hepatocellular carcinoma (HCC), and the rate of HBV infection in liver cancer patients in China is as high as 92.05%. Due to long-term exposure to chronic antigens from the gut, the liver needs to maintain a certain level of immune tolerance, both to avoid severe inflammation caused by non-pathogenic antigens and to maintain the possibility of rapid and violent responses to infection and tumors. Therefore, HBV infection interacts with the tumor microenvironment (TME) through a highly complex and intertwined signaling pathway, which results in a special TME in HCC. Due to changes in the TME, tumor cells can evade immune surveillance by inhibiting tumor-specific T cell function through cytotoxic T-lymphocy-associated protein-4 (CTLA-4) and programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1). Interferons, as a class of immune factors with strong biological activity, can improve the TME of HBV-HCC through various pathways. In recent years, the systematic treatment of HCC has gradually come out of the dilemma. In addition to the continuous emergence of new multi-target anti-vascular tyrosine kinase inhibitor drugs, immune checkpoint inhibitors have opened up a new avenue for the systematic treatment of HCC. At present, immunotherapy based on PD-1/L1 inhibitors has gradually become a new direction of systematic treatment for HCC, and the disease characteristics of patients included in global clinical studies are different from those of Chinese patients. Therefore, whether a group of HCC patients with HBV background and poor prognosis in China can also benefit from immunotherapy is an issue of wide concern. This review aims to elucidate the advances of immunotherapy for HBV related HCC patients with regard to: (1) Immunotherapy based on interferons; (2) Immunotherapy based on PD-1/L1 inhibitors; (3) Immunotherapy based on CTLA4 inhibitors; (4) Adoptive cell transfer; (5) Combination immunotherapy strategy; and (6) Shortcomings of immunotherapy.

Evaluation of the safety of PD-1/PD-L1 inhibitors for immunotherapy in patients with malignant tumors after COVID-19 infection: A single-center cohort study

INTRODUCTION

An increasing body of evidence suggests a close association between COVID-19 infection and the safety of PD-1/PD-L1 inhibitor therapy in cancer patients. However, the available data concerning these impacts remain limited and occasionally contradictory.

MATERIAL AND METHODS

We conducted a retrospective analysis of cancer patients who received PD-1/PD-L1 inhibitor therapy at the same institution from November 2022 to May 2023. After excluding patients with missing information, a total of 224 cases were included. In our study, immune-related adverse events (irAEs) that occurred during the hospitalization of patients were included in the analysis. Further analysis of inter-subgroup differences was conducted following a 1:2 propensity score matching. Statistical analyses were performed using the Fisher's exact, chi-squared, and Mann-Whitney U-tests.

RESULT

The results showed that no statistically significant differences between the two subgroups in the incidence of irAEs, changes in immune function before and after using PD-1/PD-L1 inhibitors, and alterations in hepatic and renal function (p > 0.05).

CONCLUSION

Our findings suggest that infection with COVID-19 does not significantly impact the safety of PD-1/PD-L1 inhibitors in cancer patients. Most cancer patients used PD-1/PD-L1 inhibitors during COVID-19 infection (asymptomatic or mild infection) did not experience exacerbation of their underlying condition, nor did they exhibit a substantial increase in toxic side effects.