TIGIT as an emerging immune checkpoint

Unlocking the potential of TIGIT in enhancing therapeutic strategies for acute myeloid leukemia through combined azacitidine therapy

Immune checkpoint blockade (ICB) therapy has emerged as a pivotal advancement in cancer treatment, yet its efficacy varies among patients and resistance can develop. This study focuses on TIGIT, a newly identified immune checkpoint, to explore its expression, prognostic significance, and therapeutic potential in hematologic malignancies, particularly acute myeloid leukemia (AML). In this study, we found TIGIT highest expression levels in bone marrow and lymphoid tissues, with enrichment in immune cells such as NK-T cells and regulatory T cells (Tregs). A prognostic model incorporating TIGIT expression and other immune-related genes effectively stratified AML patients into high-risk and low-risk groups, with the former displaying significantly shorter overall survival times. Our model outperformed traditional prognostic factors, highlighting TIGIT's potential as a superior predictive biomarker. Additionally, our in vitro and in vivo studies showed that combining tiragolumab with azacitidine (AZA) synergistically enhanced anti-tumor efficacy, reducing tumor burden and extending survival in a murine AML model. Our findings underscore TIGIT's role in hematologic malignancies and its potential as a therapeutic target in AML. The combination of AZA with TIGIT inhibition offers a promising new approach for AML treatment, warranting further clinical evaluation.

Overcoming chimeric antigen receptor-T (CAR-T) resistance with checkpoint inhibitors: Existing methods, challenges, clinical success, and future prospects : A comprehensive review

Immune checkpoint blockade is, as of today, the most successful form of cancer immunotherapy, with more than 43 % of cancer patients in the US eligible to receive it; however, only up to 12.5 % of patients respond to it. Similarly, adoptive cell therapy using bioengineered chimeric antigen receptorT (CAR-T) cells and T-cell receptor (TCR) cells has provided excellent responses against liquid tumours, but both forms of immunotherapy have encountered challenges within a tumour microenvironment that is both lacking in tumour-specific T-cells and is strongly immunosuppressive toward externally administered CAR-T and TCR cells. This review focuses on understanding approved checkpoint blockade and adoptive cell therapy at both biological and clinical levels before delving into how and why their combination holds significant promise in overcoming their individual shortcomings. The advent of next-generation checkpoint inhibitors has further strengthened the immune checkpoint field, and a special section explores how these inhibitors can address existing hurdles in combining checkpoint blockade with adoptive cell therapy and homing in on our cancer target for long-term immunity.

Immunotherapy in OSCC: Current trend and challenges

OBJECTIVES

Oral Cancer is one of the most prevalent malignant tumors of the head and neck. The three primary clinical treatments available till now for oral cancer are chemotherapy, radiation, and surgery. The goal of this review was to outline the basic principles of immunotherapy along with various immunotherapeutic agents on Oral Squamous Cell Carcinoma.

MATERIALS AND METHODS

A comprehensive search in PubMed, Scopus, and Google Scholar was performed using relevant keywords. All the articles, both English as well as non-English were included also with inclusion data from high-incidence countries (South-east Asia) and the compilation was ten done after getting the data reviewed from two pathologists who were blinded to the data.

RESULTS

All the data has been compiled and the various sections in the manuscript provides an insight into the current trends in immunotherapy.

CONCLUSIONS

Advanced research studies are needed to counteract the hurdles associated with immunotherapy so that a greater proportion of patients can be treated.

CLINICAL RELEVANCE

One of the more recent developments that is promising is immunotherapy, which can be quite beneficial when used as a monotherapy or an adjuvant treatment. This more recent treatment approach could serve as the fourth pillar in cancer care, alongside radiation, chemotherapy, and surgery. Because immunotherapy relies on the patient's immunological environment, careful patient selection is essential to its effectiveness.

Revealing the mechanisms and therapeutic potential of immune checkpoint proteins across diverse protein families

Host immune responses to antigens are tightly regulated through the activation and inhibition of synergistic signaling networks that maintain homeostasis. Stimulatory checkpoint molecules initiate attacks on infected or tumor cells, while inhibitory molecules halt the immune response to prevent overreaction and self-injury. Multiple immune checkpoint proteins are grouped into families based on common structural domains or origins, yet the variability within and between these families remains largely unexplored. In this review, we discuss the current understanding of the mechanisms underlying the co-suppressive functions of CTLA-4, PD-1, and other prominent immune checkpoint pathways. Additionally, we examine the IgSF, PVR, TIM, SIRP, and TNF families, including key members such as TIGIT, LAG-3, VISTA, TIM-3, SIRPα, and OX40. We also highlight the unique dual role of VISTA and SIRPα in modulating immune responses under specific conditions, and explore potential immunotherapeutic pathways tailored to the distinct characteristics of different immune checkpoint proteins. These insights into the unique advantages of checkpoint proteins provide new directions for drug discovery, emphasizing that emerging immune checkpoint molecules could serve as targets for novel therapies in cancer, autoimmune diseases, infectious diseases, and transplant rejection.

CD155 expression and co-expression with PD-L1 are not associated with poor prognosis in patients with stage II and III lung adenocarcinoma undergoing surgical resection

BACKGROUND

CD155 has been identified as a ligand for T-cell immunoreceptor with Ig and ITIM domains. Herein, we investigated the relationship between the expressions of CD155 and programmed cell death-ligand 1 (PD-L1) and clinical outcomes in patients with surgically resected lung adenocarcinoma.

METHODS

This study included 426 patients diagnosed with pathological stage (pStage) I-III lung adenocarcinoma who underwent surgery at Kyushu University Hospital. The number of tumor cells expressing CD155 and PD-L1 was assessed by immunohistochemistry, and the clinical significance of CD155 expression and CD155/PD-L1 co-expression in prognosis was investigated.

RESULTS

Among the enrolled cohort, 320 (75.1%), 60 (14.1%), and 46 (10.8%) patients were diagnosed with pStage I, II, and III, respectively. Tissues from 112 patients (26.3%) were classified as having high CD155 expression. Co-expression of CD155 and PD-L1 was observed in 44 patients (10.3%). The High CD155 and CD155/PD-L1 co-expression groups had significantly poorer prognosis in pStage I-III lung adenocarcinoma. However, subgroup analysis revealed that the clinical significance of both CD155 expression and CD155/PD-L1 co-expression differed widely between patients with pStage I and II-III. Multivariate Cox proportional hazards regression analyses showed that high CD155 expression and CD155/PD-L1 co-expression were not independent poor prognostic factors in pStage II-III lung adenocarcinoma.

CONCLUSION

Our findings suggest that neither CD155 expression or CD155/PD-L1 co-expression are associated with poor prognosis in pStage II-III lung adenocarcinoma.

New Therapeutic Targets TIGIT, LAG-3 and TIM-3 in the Treatment of Advanced, Non-Small-Cell Lung Cancer

The introduction of immunotherapy and target therapy into clinical practice has become a chance for many patients with cancer to prolong their survival while maintaining optimal quality of life. Treatment of lung cancer is excellent evidence of the progress of medical therapies. An understanding of the mechanisms of tumor development has led to the evolution of new methods of treatment. Immunoreceptors of T cells with the immunoglobulin domain ITIM, TIM-3 (T-cell immunoglobulin- and mucin domain-3-containing molecule 3), and LAG-3 (lymphocyte activation gene-3) represent new interesting therapeutic targets. The combination of anti-PD-1 and anti-CTLA-4 blockade has proven the possibility of strengthening the anti-tumor response by acting via two separate mechanisms. Adding additional checkpoints to the PD-1 blockade offers hope for further improvements in the effects of the treatment of patients and expanding the group responding to immunotherapy. This paper presents new promising molecular targets along with studies demonstrating the treatment results using them.

Immune evasion and resistance in breast cancer

Breast cancer (BC) is the most common malignancy in females with an increasing incidence in the last decade. The previously observed decline in BC mortality rates has also slowed down recently with an increase in the incidence of invasive BC. BC has various molecular subtypes. Among these subtypes, triple-negative breast cancer (TNBC) represents the most aggressive BC, with a poor prognosis. Because lack of the hormonal or human epidermal growth factor receptor 2 (HER2) receptors, TNBC is resistant to hormonal and HER2 targeted therapy effective for other BC subtypes. The good news is that TNBC has recently been considered an immunologically 'hot' tumor. Therefore, immunotherapy, particularly immune checkpoint inhibitor therapy, represents a promising therapeutic approach TNBC. However, a considerable percentage of patients with TNBC do not respond well to immunotherapy, indicating that TNBC seems to adopt several mechanisms to evade immune surveillance. Thus, it is crucial to investigate the mechanisms underlying TNBC immune evasion and resistance to immunotherapy. In this review, we examine and discuss the most recently discovered mechanisms for BC, with a particular focus on TNBC, to evade the immune surveillance via kidnapping the immune checkpoints, suppressing the immune responses in tumor microenvironment and inhibiting the tumor antigen presentation. Evaluation of these mechanisms in BC will hopefully guide future immunotherapeutic research and clinical trials.

Targeting the poliovirus receptor to activate T cells and induce myeloid-derived suppressor cells to differentiate to pro-inflammatory macrophages via the IFN-γ-p-STAT1-IRF8 axis in cancer therapy

T cell immunoglobulin and ITIM domain (TIGIT) is one of the most important immune checkpoints expressed on lymphocytes, and poliovirus receptor (PVR, also CD155) serves as the most crucial ligand for TIGIT, harboring an important function in cancer cells and influencing the tumor microenvironment (TME). While it's well-established that TIGIT blockade could reverse immunosuppression, the question of whether direct inhibition of PVR yields comparable results remains to be fully elucidated. This study investigated the role of PVR within the TME on the LLC, CT26 and MC38 tumor models and found that direct blockade of PVR on tumor cells could trigger T cell activation, enhance the production of immunostimulatory cytokine IFN-γ, and drive the differentiation of intratumoral myeloid-derived suppressor cells (MDSCs) into pro-inflammatory macrophages through the IFN-γ-p-STAT1-IRF8 axis. Furthermore, this study found that the anti-PVR nanobody monotherapy reduced tumor volume in the CT26 and MC38 tumor models. Combination of anti-PVR nanobody and anti-PD-1 antibody was effective in the LLC, CT26 and MC38 tumor models and had acceptable toxicity. These findings collectively suggest that PVR exhibits considerable promise as a therapeutic target in the development of immunotherapies aimed at augmenting the anti-tumor immune response.

Navigating established and emerging biomarkers for immune checkpoint inhibitor therapy

Immune checkpoint inhibitors (ICIs) have improved outcomes of patients with many different cancers. These antibodies target molecules such as programmed cell death 1 (PD-1) or cytotoxic T lymphocyte associated protein 4 (CTLA-4) which normally function to limit immune activity. Treatment with ICIs reactivates T cells to destroy tumor cells in a highly specific manner, which in some patients, results in dramatic remissions and durable disease control. Over the last decade, much effort has been directed at characterizing factors that drive efficacy and resistance to ICI therapy. Food and Drug Administration (FDA)-approved biomarkers for ICI therapy have facilitated more judicious treatment of cancer patients and transformed the field of precision oncology. Yet, adaptive immunity against cancers is complex, and newer data have revealed the potential utility of other biomarkers. In this review, we discuss the utility of currently approved biomarkers and highlight how emerging biomarkers can further improve the identification of patients who benefit from ICIs.

Natural killer cells: the immune frontline against circulating tumor cells

Natural killer (NK) play a key role in controlling tumor dissemination by mediating cytotoxicity towards cancer cells without the need of education. These cells are pivotal in eliminating circulating tumor cells (CTCs) from the bloodstream, thus limiting cancer spread and metastasis. However, aggressive CTCs can evade NK cell surveillance, facilitating tumor growth at distant sites. In this review, we first discuss the biology of NK cells, focusing on their functions within the tumor microenvironment (TME), the lymphatic system, and circulation. We then examine the immune evasion mechanisms employed by cancer cells to inhibit NK cell activity, including the upregulation of inhibitory receptors. Finally, we explore the clinical implications of monitoring circulating biomarkers, such as NK cells and CTCs, for therapeutic decision-making and emphasize the need to enhance NK cell-based therapies by overcoming immune escape mechanisms.

The Role of NK Cells in Cancer Immunotherapy: Mechanisms, Evasion Strategies, and Therapeutic Advances

Background/Objectives: Natural killer (NK) cells play a crucial role in tumor surveillance by exerting cytotoxic activity and modulating immune responses. However, tumors employ diverse evasion strategies that limit NK cell effectiveness. This review aims to explore the molecular mechanisms of NK cell activation and inhibition in cancer, the influence of the tumor microenvironment, and the latest advancements in NK cell-based immunotherapies, including adoptive NK cell transfer and Chimeric Antigen Receptor-Natural Killer (CAR-NK) cell therapies. Methods: A comprehensive literature review was conducted, prioritizing peer-reviewed studies from the last decade on NK cell biology, tumor immune evasion, and immunotherapeutic applications. The analysis includes data from preclinical models and clinical trials evaluating NK cell expansion strategies, cytokine-based stimulation, and CAR-NK cell therapy developments. Results: NK cells eliminate tumors through cytotoxic granule release, death receptor pathways, and cytokine secretion. However, tumor cells evade NK-mediated immunity by downregulating activating ligands, secreting immunosuppressive molecules, and altering the tumor microenvironment. Novel NK cell-based therapies, such as CAR-NK cells and combination approaches with immune checkpoint inhibitors, enhance NK cell persistence and therapeutic efficacy against both hematologic and solid malignancies. Clinical trials suggest improved safety profiles compared to CAR-T therapies, with reduced cytokine release syndrome and graft-versus-host disease. Conclusions: While NK cell-based immunotherapies hold great promise, challenges remain, including limited persistence and tumor-induced immunosuppression. Addressing these hurdles will be critical for optimizing NK cell therapies and advancing next-generation, off-the-shelf immunotherapeutics for broader clinical applications.

Immune Checkpoint Molecules: A Review on Pathways and Immunotherapy Implications

BACKGROUND

Today, treating cancer patients with monoclonal antibodies (mAbs), by targeting immune checkpoints, is one of the most outstanding immunotherapeutic methods. Immune checkpoints are special molecules having regulatory role in immune system responses. Once these molecules are presented on cancer cells, these cells will be capable of evading the immune system through their own specific pathways. This Evasion can be prevented by counterbalancing immune system responses with immune checkpoints related antibodies.

AIMS

The current study aimed to highlight immunotherapy and its methods, describe the immune checkpoints pathways, outline the immune checkpoint inhibitors (ICIs), and recent advances in this field, and sketch an outlook on the best treatment options for the most prevalent cancers.

MATERIALS & METHODS

This research implemented a narrative review method. A comprehensive literature review on the history, molecular and cellular biology, and the clinical aspects of immune checkpoint molecules was performed to illustrate the pathways involved in various cancers. Also, currently-available and future potential immunotherapies targeting these pathways were extracted from the searched studies.

RESULTS

The immune checkpoint family consists of many molecules, including CTLA-4, PD-1, PD-L1, LAG-3, TIM-3, and TIGIT. Attempts to modify these molecules in cancer treatment led to the development of therapeutic monoclonal antibodies. Most of these antibodies have entered clinical studies and some of them have been approved by the Food and Drug Administration (FDA) to be used in cancer patients' treatment plans.

DISCUSSION

With these novel treatments and the combination therapies they offer, there is also hope for better treatment outcomes for the previously untreatable metastatic cancers. In spite of the beneficial aspects of immune checkpoint therapy, similar to other treatments, they may cause side effects in some patients. Therefore, more studies are needed to reduce the probable side effects and uncover their underlying mechanism.

CONCLUSION

Based on the data shown in this review, there is still a lack of knowledge about the complete properties of ICIs and the possible combination therapies that we may be able to implement to achieve a better treatment response in cancer patients.

Small molecules targeting immune checkpoint proteins for cancer immunotherapy: a patent and literature review (2020-2024)

INTRODUCTION

Targeting immune checkpoint proteins (ICPs) via small molecules open a new window for cancer immunotherapy. Herein, we summarize recent advances of small molecules with novel chemical structures targeting ICPs, discusses their anti-tumor efficacies, which are important for the development of novel small molecules for cancer immunotherapy.

AREAS COVERED

In this review, the latest patents and literature were gathered through the comprehensive searches in the databases of European Patent Office (EPO), Cortellis Drug Discovery Intelligence (CDDI), PubMed and Web of Science using ICPs and compounds as key words.

EXPERT OPINION

To develop novel weapons to fight against cancer, small molecules targeting ICPs including CTLA-4, LAG-3, PD-L1, Siglec-9, TIM-3, TIGIT, and VISTA have been synthesized and evaluated in succession. Chief among them are the small molecules targeting PD-L1, which have been intensively investigated in recent years. Various in vitro assays such as ALPHA, HTRF binding assay, NFAT assay have been successfully developed to screen novel IPCs inhibitors. However, the in vivo assay, for example, using double-humanized PD-1/PD-L1 (hPD-1/hPD-L1) mouse as evaluation model, are seldom reported. Novel pharmacophores with new working mechanisms such as proteolysis targeting chimeras (PROTACs) and peptides are needed to enhance the therapeutic efficacy.

Heterogeneity of γδ T-cell subsets and their clinical correlation in patients with AML

Background

γδ T cells are integral elements of the immune system and have shown therapeutic potential in the treatment of acute myeloid leukemia (AML). Nevertheless, the influence of distinct functional subsets, including the activating marker NKG2D, the immune exhaustion marker TIGIT, and the regulatory marker Foxp3, on therapeutic outcomes in AML patients remains unknown.

Methods

First, we analyzed RNA-seq data from 167 patients in The Cancer Genome Atlas (TCGA) database, concentrating on the correlations between NKG2D, TIGIT, and Foxp3 gene expressions and their association with prognosis in AML. We employed flow cytometry to assess the expression of these molecular markers on γδ T cells and the Vδ1/Vδ2 subsets in the peripheral blood of 25 de novo AML (AML-DN) patients, 15 patients in complete remission (CR), and 27 healthy controls (HCs). We also analyzed the relationship between the expression frequencies of NKG2D, TIGIT, and Foxp3 on γδ T cells and their subsets, and their clinical outcomes.

Results

Based on data from TCGA database, we found that a high expression level of NKG2D in combination with a low expression level of TIGIT was significantly associated with longer overall survival (OS) in AML patients. Clinical data revealed that γδ T cells from AML-DN patients exhibited higher expression levels of TIGIT and Foxp3, whereas NKG2D expression was lower compared to that of HCs. Notably, the expression of the NKG2D+TIGIT- Vδ1 subset was significantly reduced in AML-DN patients compared to CR patients. Univariate logistic regression and Cox regression analyses further indicated that a high expression of the NKG2D+TIGIT- Vδ1 subset was associated with better clinical prognosis.

Conclusion

This study indicates that NKG2D+TIGIT- Vδ1 T cells are strongly correlated with improved prognosis in AML, and future research should investigate their potential in adoptive immunotherapy to advance more personalized and precise treatment strategies.

Review on recent advancements in understanding acetylsalicylic acid-induced gastrointestinal injury: mechanisms, medication, and dosage refinement

Acetylsalicylic acid (ASA) is a clinical drug with multiple effects, including prevention of cardiovascular adverse events and anti-cancer effects. However, gastrointestinal side effects, such as gastrointestinal ulcers and bleeding, limit the use of ASA and reduce patient compliance. Various studies have investigated the mechanisms of ASA-induced gastrointestinal injury, and many medicines have been reported to be effective in preventing and treating the adverse gastrointestinal effects of ASA. New formulations of ASA have demonstrated milder gastrointestinal injury than ASA alone. In this article, we summarized the mechanisms of ASA-induced gastrointestinal injury, drugs that resist gastrointestinal side effects of ASA, and progress in research on formulation improvement of ASA to help resolve the clinical dilemma of ASA usage.

Computational screening for natural compounds as potential immune checkpoint inhibitors against TIGIT, a new avenue in cancer immunotherapy

The TIGIT-PVR signalling pathway is a key mechanism of tumour immune evasion, making it an attractive target for cancer immunotherapy. Despite the recent advances in anti-TIGIT antibodies, monoclonal antibody-based therapeutics present significant challenges because of their immunogenicity and immune-related side effects. This study presents a new path involving natural compounds as potential small molecule inhibitors of TIGIT, providing a possible alternative to antibodies in cancer immunotherapy. Through a comprehensive in silico workflow combining structure-based virtual screening, ADMET analysis, Molecular docking and molecular dynamics simulations, six promising candidates, mostly of bacterial origin, were identified: Neomycin K, 4'-Deoxybutirosin A, 5-Glucosyl-neamine, S-11-A, 12-carbamoylstreptothricin E acid, and Zwittermicin A. These candidates demonstrated favourable binding energies, stable interactions, and the capacity to block TIGIT-PVR signalling. The compounds can potentially compete with PVR to bind to TIGIT, limiting the formation of the TIGIT-PVR complex, which typically activates an inhibitory cascade in T cells and NK cells, reducing their anti-tumour activity. By disrupting this interaction, the identified compounds have the potential to stimulate T cell and NK cell responses against cancer cells. Such natural compounds potentially provide better tissue penetration and reduced immunogenicity compared to conventional antibody therapies. The discovery of bacterial-derived compounds as TIGIT inhibitors presents a new direction in the investigation of microbial metabolites for cancer immunotherapy. This strategy not only identifies a new class of TIGIT inhibitors but also provides a robust computational framework for discovering and characterizing small molecule immune checkpoint inhibitors, paving the way for subsequent experimental validation to explore their efficacy in restoring anti-tumour immune responses and improving clinical outcomes for cancer patients.

Mesenchymal stromal cells in bone marrow niche of patients with multiple myeloma: a double-edged sword

Multiple myeloma (MM) is a hematological malignancy defined by the abnormal proliferation and accumulation of plasma cells (PC) within the bone marrow (BM). While multiple myeloma impacts the bone, it is not classified as a primary bone cancer. The bone marrow microenvironment significantly influences the progression of myeloma and its treatment response. Mesenchymal stromal cells (MSCs) in this environment engage with myeloma cells and other bone marrow components via direct contact and the secretion of soluble factors. This review examines the established roles of MSCs in multiple facets of MM pathology, encompassing their pro-inflammatory functions, contributions to tumor epigenetics, effects on immune checkpoint inhibitors (ICIs), influence on reprogramming, chemotherapy resistance, and senescence. This review investigates the role of MSCs in the development and progression of MM.

Unraveling the breast cancer tumor microenvironment: crucial factors influencing natural killer cell function and therapeutic strategies

Natural killer (NK) cells have emerged as a novel and effective treatment for breast cancer. Nevertheless, the breast cancer tumor microenvironment (TME) manifests multiple immunosuppressive mechanisms, impeding the proper execution of NK cell functions. This review summarizes recent research on the influence of the TME on the functionality of NK cells in breast cancer. It delves into the effects of the internal environment of the TME on NK cells and elucidates the roles of diverse stromal components, immune cells, and signaling molecules in regulating NK cell activity within the TME. It also summarizes therapeutic strategies based on small-molecule inhibitors, antibody therapies, and natural products, as well as the progress of research in preclinical and clinical trials. By enhancing our understanding of the immunosuppressive TME and formulating strategies to counteract its effects, we could fully harness the therapeutic promise of NK cells in breast cancer treatment.

Identification of new immune target and signaling for cancer immunotherapy

Immunotherapy has become one of the innovative treatments in malignancy as it activates the immune system to find and eliminate malignant cells. The tumor immunology interface has become increasingly intricate, making the identification of new immune targets and signalling pathways on which to base improved therapeutic strategies an ongoing process. This review, we goal to clarify the contacts between cancer and immune system with a focus on immune surveillance as well as immune evasion mechanisms. Comprehensive immunotherapeutic therapies are overviewed with ICI (CTLA-4, PD-1, PD-L1), CAR-T cell therapy, and cancer vaccines whereas, advanced therapies targeting new immune checkpoints are also elucidated including TIM-3, LAG-3, and TIGIT. The JAK/STAT, MAPK and PI3K-AKT-mTOR pathways are reviewed with regards to cancer progression and immunotherapeutic resistance. The dysregulation of these pathways gives hope for the identification of fresh targets for therapy. Genomics, proteomics, immunopeptidomics, single cell mass spectrometry, CRISPR-based functional genomics and bioinformatics are described as essential for immune target identification and for mapping of cancer relevant signaling pathways. This review also considers some emerging issues in the subject area like the tumor heterogeneity, immune-related adverse events (irAEs), and personalized treatment. These barriers are described to facilitate the understanding of ways to overcome them and increase the efficacy of immunotherapies through combination therapies. This means that by developing new knowledge of immunological targets and pathways, immunoprecision medicine for cancer could greatly enhance outcomes.

Molecular Mechanisms in the Transformation from Indolent to Aggressive B Cell Malignancies

Histological transformation (HT) into aggressive lymphoma is a turning point in a significant fraction of patients affected by indolent lymphoproliferative neoplasms, namely, chronic lymphocytic leukemia (CLL), follicular lymphoma (FL), marginal zone lymphomas (MZLs), and lymphoplasmacytic lymphoma (LPL) [...].

Targeting Immune Checkpoint Inhibitors for Non-Small-Cell Lung Cancer: Beyond PD-1/PD-L1 Monoclonal Antibodies

Non-small-cell lung cancer (NSCLC) remains a leading cause of cancer-related mortality worldwide. Immunotherapy targeting the PD-1/PD-L1 axis has revolutionized treatment, providing durable responses in a subset of patients. However, with fewer than 50% of patients achieving significant benefits, there is a critical need to expand therapeutic strategies. This review explores emerging targets in immune checkpoint inhibition beyond PD-1/PD-L1, including CTLA-4, TIGIT, LAG-3, TIM-3, NKG2A, and CD39/CD73. We highlight the biological basis of CD8 T cell exhaustion in shaping the antitumor immune response. Novel therapeutic approaches targeting additional inhibitory receptors (IR) are discussed, with a focus on their distinct mechanisms of action and combinatory potential with existing therapies. Despite significant advancements, challenges remain in overcoming resistance mechanisms and optimizing patient selection. This review underscores the importance of dual checkpoint blockade and innovative bispecific antibody engineering to maximize therapeutic outcomes for NSCLC patients.

TIGIT/PVR axis regulates anti-tumor immunity in hematologic malignancies

Hematologic malignancy stands as a grave form of cancer characterized by its arduous treatment and heightened likelihood of recurrence. Over the recent years, immunotherapy has progressively evolved into a pivotal approach for addressing hematologic malignancies. As a novel inhibitory receptor of NK and T cells, TIGIT is similar to PD-1, and blocking TIGIT can play a huge anti-tumor effect. At present, target TIGIT is still in clinical trials. Within this context, the TIGIT/PVR axis, serving as a pivotal element within the immunomodulatory framework, assumes a critical role in tumor immunity orchestration. This composition delves into the advancement of research concerning the TIGIT/PVR axis within hematologic malignancies, elucidating its mechanism for impeding anti-tumor immune responses. Furthermore, potential therapeutic avenues are explored, encompassing immunotherapeutic strategies aimed at targeting the TIGIT/PVR axis, alongside the conceivable integration with alternative immune checkpoint inhibitors. Ultimately, the paper encapsulates forthcoming research trajectories, aspiring to provide a compass for deeper comprehension of the TIGIT/PVR axis's role within hematologic malignancies, consequently fostering the creation of more potent immunotherapeutic tactics. This review details the therapeutic prospects of TIGIT in hematological malignancies, which is expected to advance research targeting TIGIT in hematological malignancies and bring hope for survival to these patients.

Advances in Immunotherapy in Hepatocellular Carcinoma

Over the past several years, the therapeutic landscape for patients with advanced, unresectable, or metastatic hepatocellular carcinoma has been transformed by the incorporation of checkpoint inhibitor immunotherapy into the treatment paradigm. Frontline systemic treatment options have expanded beyond anti-angiogenic tyrosine kinase inhibitors, such as sorafenib, to a combination of immunotherapy approaches, including atezolizumab plus bevacizumab and durvalumab plus tremelimumab, both of which have demonstrated superior response and survival to sorafenib. Additionally, combination treatments with checkpoint inhibitors and tyrosine kinase inhibitors have been investigated with variable success. In this review, we discuss these advances in systemic treatment with immunotherapy, with a focus on understanding both the underlying biology and mechanism of these strategies and their efficacy outcomes in clinical trials. We also review challenges in identifying predictive biomarkers of treatments and discuss future directions with novel immunotherapy targets.

A combination of PD-1 and TIGIT immune checkpoint inhibitors elicits a strong anti-tumour response in mesothelioma

BACKGROUND

Finding effective and curative treatment for mesothelioma remains challenging. While the introduction of immunotherapy combinations using ipilimumab (anti-CTLA-4) and nivolumab (anti-PD-1) have offered hope for some patients, a large proportion of mesothelioma cases, particularly the epithelial subtype, have minimal benefit from this.

METHODS

Our study was inspired by the results of the AdvanTG-105 phase I clinical trial, which showed partial response with anti-TIGIT/PD-1 treatment in two epithelioid mesothelioma patients. Here, we conducted a comprehensive in vivo experiment involving eight animal treatment groups administered with either PBS (control group), cisplatin/pemetrexed, anti-PD-1, anti-PD-1 + anti-CTLA-4, anti-TIGIT, anti-PD-1 + anti-TIGIT, anti-PD-1 + anti-CTLA-4 + anti-TIGIT, and cisplatin/pemetrexed + anti-PD-1 + anti-TIGIT.

RESULTS

Our results indicate that animals receiving anti-PD-1 + TIGIT exhibited a superior anti-tumour response, with 90% of the treatment group exhibiting an objective response, compared to 60%, 20% and 40% for the standard-of-care anti-PD-1 + CTLA-4, single-agent anti-PD-1 and cisplatin/pemetrexed treatment groups, respectively. Animals receiving anti-PD-1 + TIGIT displayed a significantly reduced average tumour size, with improved weight and survival rates, and fewer adverse effects than those receiving anti-PD-1 + CTLA-4 treatment. Anti-PD-1 + TIGIT-treated animals achieved complete tumour regression, with heightened effector CD8 + T cell and NK cell activity, remaining tumour-free for over 300 days without immune-related adverse events. After initial tumour elimination, anti-PD-1 + TIGIT-treated animals showed no tumour regrowth in the rechallenge experiment.

CONCLUSION

These findings provide rationale for the development of an anti-PD-1 + TIGIT combination immunotherapy trial for mesothelioma patients.

TIGIT inhibitor M6223 as monotherapy or in combination with bintrafusp alfa in patients with advanced solid tumors: a first-in-human, phase 1, dose-escalation trial

BACKGROUND

M6223 is an intravenous (IV), Fc-competent, fully human, antagonistic, anti-T cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains (TIGIT) antibody. Bintrafusp alfa (BA) is a bifunctional fusion protein that simultaneously blocks nonredundant immunosuppressive TGF-β and PD-(L)1 pathways.

METHODS

This first-in-human, dose-escalation study in patients with advanced solid tumors (N=58; aged ≥18 years, ECOG PS≤1) evaluated M6223 alone (Part 1A, n=40; M6223 10-2400 mg every 2 weeks, n=32; M6223 2400 mg every 3 weeks, n=8) or with BA (Part 1B, n=18; M6223 300-1600 mg with BA 1200 mg; both every 2 weeks, intravenous). Primary objectives were safety, tolerability, maximum tolerated dose (MTD) and recommended dose for expansion (RDE). Additional objectives included pharmacokinetics, pharmacodynamics and clinical activity (NCT04457778).

RESULTS

Two dose-limiting toxicities were observed: grade 3 adrenal insufficiency (Part 1A: M6223 900 mg every 2 weeks) and grade 3 anemia (Part 1B: M6223 300 mg, only BA related). MTD was not reached. Overall, median overall survival and progression-free survival were 7.6 (95% CI 4.9, 12.0) and 1.4 (95% CI 1.3, 1.8) months, respectively. Stable disease as best response was observed in 13 (32.5%) and 5 (27.8%) patients in parts 1A and 1B, respectively. M6223±BA displayed a linear pharmacokinetic profile. Anti-TIGIT mode-of-action-related pharmacodynamic effects were observed in peripheral blood and in tumor tissue. RDEs were 1600 mg every 2 weeks or 2400 mg every 3 weeks for M6223 monotherapy and 1600+1200 mg every 2 weeks for M6223+BA.

CONCLUSIONS

M6223±BA had a manageable safety profile, with RDEs defined for both monotherapy and combination therapy. Further evaluation of M6223 is ongoing in combination with the PD-L1 inhibitor avelumab in patients with advanced urothelial carcinoma (JAVELIN Bladder Medley; NCT05327530).

TRIAL REGISTRATION NUMBER

NCT04457778.

TIGIT Regulates T Cell Inflammation in Airway Inflammatory Diseases

TIGIT, a co-inhibitory receptor found on T cells and NK cells, transmits inhibitory signals upon binding to its ligand. This interaction suppresses the activation of various signaling pathways, leading to functional exhaustion of cells, ultimately dampening excessive inflammatory responses or facilitating immune evasion in tumors. Dysregulated TIGIT expression has been noted in T cells across different inflammatory conditions, exhibiting varying effects based on T cell subsets. TIGIT predominantly restrains the effector function of pro-inflammatory T cells, upholds the suppressive function of regulatory T cells, and influences Tfh maturation. Mechanistically, the IL27-induced transcription factors c-Maf and Blimp-1 are believed to be key regulators of TIGIT expression in T cells. Notably, TIGIT expression in T cells is implicated in lung diseases, particularly airway inflammatory conditions such as lung cancer, obstructive pulmonary disease, interstitial lung disease, sarcoidosis, and COVID-19. This review emphasizes the significance of TIGIT in the context of T cell immunity and airway inflammatory diseases.

Immune checkpoints in B-cell Lymphoma: Still an Unmet challenge from Basic research to clinical practice

In the last decade, advancements in immunotherapy knowledge have highlighted CTLA-4, PD-1, LAG-3, TIM-3, and TIGIT, decisive immune checkpoints exhibiting within the tumor microenvironment (TME), as fundamental objects for cancer immunotherapy. The widespread clinical use of immune checkpoint inhibitors (ICls), employing PD-1/PD-L1 or CTLA-4 antibodies to obstruct crucial checkpoint regulators, is noted in treating B-cell lymphoma patients. Nevertheless, the prolonged advantages of the currently employed treatments against CTLA-4, PD-1, and PD-L1 are uncommon among patients. Thus, recent focus has been progressively moved to additional immune checkpoints on T cells, like LAG-3, TIM-3, and TIGIT, which are now seen as reassuring targets for treatment and broadly acknowledged. There are several types of immunecheckpoint molecules expressed by T cells, and inhibitors targeting immune checkpoints can revive and amplify the immune response of T lymphocytes against tumors, a crucial aspect in lymphoma therapy. However, there is little knowledge about their regulation. Herein, we discuss the anti-tumor effects and functions of ICIs in controlling T-cell activity, as well as the progress in combined application with other immunotherapies.

Single-cell RNA sequencing comparison of CD4+, CD8+ and T-cell receptor γδ+ cutaneous T-cell lymphomas reveals subset-specific molecular phenotypes

BACKGROUND

Malignant clones of primary cutaneous T-cell lymphomas (CTCL) can show a CD4+, CD8+ or T-cell receptor (TCR)-γδ+ phenotype, but their individual impact on tumour biology and skin lesion formation remains ill defined.

OBJECTIVES

To perform a comprehensive molecular characterization of CD4+ vs. CD8+ and TCR-γδ+ CTCL lesions.

METHODS

We performed single-cell RNA sequencing (scRNAseq) of 18 CTCL skin biopsies to compare classic CD4+ advanced-stage mycosis fungoides (MF) with TCR-γ/δ+ MF and primary cutaneous CD8+ aggressive epidermotropic cytotoxic T-cell lymphoma (Berti lymphoma).

RESULTS

Malignant clones of TCR-γ/δ+ MF and Bertilymphoma showed similar clustering patterns distinct from CD4+ MF, along with increased expression of cytotoxic markers such as NKG7, CTSW, GZMA and GZMM. Only advanced-stage CD4+ MF clones expressed central memory T-cell markers (SELL, CCR7, LEF1), alongside B1/B2 blood involvement, whereas TCR-γδ+ MF and Berti lymphoma harboured a more tissue-resident phenotype (CD69, CXCR4, NR4A1) without detectable cells in the blood. CD4+ MF and TCR-γδ+ MF skin lesions harboured strong type 2 immune activation across myeloid cells, while Berti lymphoma was more skewed toward type 1 immune responses. Both CD4+ MF and TCR-γδ+ MF lesions showed upregulation of keratinocyte hyperactivation markers such as S100A genes and KRT16. This increase was entirely absent in Berti lymphoma, possibly reflecting an aberrant keratinocyte response to invading tumour cells, which could contribute to the formation of the typical ulceronecrotic lesions within this entity.

CONCLUSIONS

Our scRNAseq profiling study reveals specific molecular patterns associated with distinct CTCL subtypes.

Multiple Myeloma Cells Shift the Fate of Cytolytic ILC2s Towards TIGIT-Mediated Cell Death

BACKGROUND

Growing evidence attests to the multifaceted roles of group 2 innate lymphoid cells (ILC2s) in cancer immunity. They exhibit either pro- or anticancer activity depending on tumor type but their function in Multiple Myeloma (MM) is still not elucidated.

METHODS

The bone marrow (BM) and peripheral blood (PB) of patients (pts) with MM or precancerous conditions were collected, and specific properties of ILC2 subsets were assessed by flow cytometry.

RESULTS

By dissecting ILC2s according to c-Kit marker, we observed that NKp30 and NKG2D were mainly confined to c-Kithi ILC2s, while levels of DNAM-1 was significantly higher in fully mature c-Kitlo cells. Among the total MM-associated ILC2s (MM-ILC2s), we observed a significant increase in c-the Kitlo subset, but the expression of DNAM-1 in these cells was significantly reduced, especially in BM. Interestingly, MM-ILC2s from PB expressed granzyme B (GZMB), but its expression was impaired in BM-ILC2s. Accordingly, MM cells were susceptible to killing by MM-ILC2s derived from PB while eluding ILC2 surveillance in BM. Indeed, in MM-ILC2s derived from BM, the downregulation of DNAM-1 is accompanied by the upregulation of TIGIT, which mediate cell death in ILC2s upon recognition of the cognate ligands expressed by MM cells. These ILC2 changes appeared in clinical precursor conditions and eventually accumulated with disease progression.

CONCLUSIONS

MM-ILC2s can act as cytolytic immune effectors that are fully competent in PB. However, MM cells shift ILC2 fate towards cell death in BM via the upregulation of TIGIT, thereby representing a potential therapeutic target to restore ILC2 antitumor activity.

Harnessing the tumor microenvironment: targeted cancer therapies through modulation of epithelial-mesenchymal transition

The tumor microenvironment (TME) is integral to cancer progression, impacting metastasis and treatment response. It consists of diverse cell types, extracellular matrix components, and signaling molecules that interact to promote tumor growth and therapeutic resistance. Elucidating the intricate interactions between cancer cells and the TME is crucial in understanding cancer progression and therapeutic challenges. A critical process induced by TME signaling is the epithelial-mesenchymal transition (EMT), wherein epithelial cells acquire mesenchymal traits, which enhance their motility and invasiveness and promote metastasis and cancer progression. By targeting various components of the TME, novel investigational strategies aim to disrupt the TME's contribution to the EMT, thereby improving treatment efficacy, addressing therapeutic resistance, and offering a nuanced approach to cancer therapy. This review scrutinizes the key players in the TME and the TME's contribution to the EMT, emphasizing avenues to therapeutically disrupt the interactions between the various TME components. Moreover, the article discusses the TME's implications for resistance mechanisms and highlights the current therapeutic strategies toward TME modulation along with potential caveats.

Effect of curcumin regulated memory Th7 cells in mice with DSS-induced colitis

Abnormal activation or dysfunction of memory helper T (mTh) cells is closely associated with the development of ulcerative colitis (UC). Curcumin (Cur), the main component of turmeric, plays a critical role in the treatment of UC due to its favorable anti-inflammatory and immunomodulatory bioactivities. However, whether Cur modulates mTh7 cells to alleviate UC is unknown. In the present study, dextran sulphate sodium (DSS) was administered to establish a colitis model in mice. Our current findings indicated that Cur effectively ameliorated the manifestations of colitis in mice, and had a significant effect in reducing disease activity index (DAI), as well as in the colonic weight and the proportion of colonic weight to colonic length. While Cur reduced the pathological injuries of the colon, restore the length of the colon, inhibited the secretion of IL-7 and IL-21, restored the secretion of IL-2, IL-4, and IL-10. Furthermore, Cur had a regulatory effect on mTh7 cells and their subpopulation status. The results of molecular docking simulations and Surface Plasmon Resonance (SPR) indicated that Cur demonstrates strong interaction capabilities with both IL-7 and IL-7R and reduced the expression levels of IL-7/IL-7R mRNA and protein. It is suggested that the alleviation of DSS-induced colitis by Cur may be achieved by reducing the level of mTh7 cells and inhibiting the activation of IL-7/IL-7R signaling.

Natural killer cell-based therapies in neuroblastoma

Neuroblastoma (NB) is the most common extracranial solid tumor of childhood forming around 15 % of all pediatric tumors. Despite advances in the treatment of NB, high-risk patients still face a grave prognosis. Adoptive cell therapies based on NK cells are becoming an assistive treatment for such cases. Moreover, there is also evidence that NKT-based therapies have promising results in the management of NB. Lower complications in comparison with adoptive T cell therapies, various cell sources, and miscellaneous tumor recognition mechanisms are some of the advantages of NK- and NKT-based therapies. This review is dedicated to searching for recent advances in this field.

Function and Spatial Organization of Tumor-Invasive Human γδ T Cells-What Do We Know?

Human gammadelta (γδ) T cells not only infiltrate or reside in healthy tissues but also enter solid cancers. A large body of evidence suggests that γδ T cells can exert potent anti-tumor effects, although conflicting or unfavorable effects have been reported in some cancer entities. Infiltration patterns are key to understanding the complexity of the tumor microenvironment (TME) and its interplay with γδ T cells. The limited data available describe different γδ T cell subsets that are located in different areas around and within tumors. Tumor-infiltrating γδ lymphocytes (γδ TIL) exert cytotoxicity, for example, via the CD95- or TRAIL-axis, produce high amounts of granzymes, and after their activation, tumor necrosis factor (TNF)-α or IFN-γ and express immune checkpoint receptors. Under certain conditions, γδ T cell subsets can express low amounts of IL-17 and seem to contribute to immune regulation/suppression. A polarization of γδ T cells can be influenced by the TME. Inflammatory cytokines, growth factors, or tumor promoters can suppress γδ T cell functionality or even push them toward tumor promotion. To avoid this and to exploit the unique features of γδ T cell-mediated anti-cancer and immune-orchestrating capabilities in future immune therapy approaches, a growing body of preclinical but also clinical studies can be observed.

Combining anti-checkpoint immunotherapies and cancer vaccines as a novel strategy in oncological therapy: A review

The field of cancer immunotherapy has experienced remarkable advancements in the treatment of human cancers over recent decades. Therapeutic cancer vaccines have been employed to elicit antitumor immune responses through the generation of specific reactions against tumor-associated antigens. Although preclinical studies have demonstrated hopeful results and at least one product is approved for clinical use, the overall efficacy of cancer vaccines remains restricted. The co-administration of anti-checkpoint antibodies alongside cancer vaccines is proposed as a potential strategy to enhance the clinical efficacy of immunotherapies. Among the various anti-checkpoint agents, monoclonal antibodies targeting CD127, OX40, and CD40 have been further investigated in combined administration with cancer vaccines, demonstrating a synergistic impact on disease outcomes in both animal models and human subjects. This combinational approach has been shown to suppress tumor regression, improve survival rates, and promote the efficacy of cancer vaccines via multiple mechanisms, including the augmentation of generation, activation, and expansion of CD8+ T cells, as well as the production of tumor-inhibitory cytokines. Importantly, the impact of the concurrent administration of anti-checkpoint agents and cancer vaccines surpass those observed with the sole vaccine, indicating that this strategy may offer significant advantages for clinical application in cancer patients. In this review, we aim to provide a comprehensive overview of the significance and therapeutic potential of the combined administration of checkpoint agonist/antagonist antibodies and cancer vaccines for human tumors.

The past, the present and the future of immune checkpoints inhibitors in multiple myeloma

INTRODUCTION

Myeloma genesis is a very complex mechanism in which the interaction between plasma cells and microenvironments with immune cells, cytokines and chemokines have a central role. In the last years, the improved knowledge of immune checkpoint models led to the development of new drugs (anti-PD1/PD-L1 axis or anti-TIGIT) that now have a crucial role in the treatment of many hematological malignancies.

AREAS COVERED

In this review, the current significant literature was discussed. In the past, initial trials combining immune checkpoint inhibitors (ICIs) with immunomodulatory drugs or proteasome inhibitors demonstrated suboptimal results in terms of efficacy and safety. On the other hand, recent trials based on the combination of ICIs with immunotherapies, such as CAR-T cells or bispecific antibodies, are a particularly promising area of investigation.

EXPERT OPINION

Our idea after the evaluation of scientific literature is that despite the past, ICIs may represent a promising therapeutic approach for myeloma, particularly when combined with CAR-T cells or bispecific antibodies. By targeting immune evasion mechanisms, ICIs may enhance the efficacy of these treatments and provide new hope for patients with resistant disease. Future research will be crucial to further elucidate their optimal use in myeloma and to develop personalized treatment strategies.

Comprehensive analysis of immune signatures in primary biliary cholangitis and autoimmune hepatitis

Primary biliary cholangitis (PBC) and autoimmune hepatitis (AIH) are autoimmune diseases that target hepatocytes and bile duct cells, respectively. Despite their shared autoimmune nature, the differences in immunologic characteristics between them remain largely unexplored. This study seeks to elucidate the unique immunological profiles of PBC and AIH and to identify key differences. We comprehensively analyzed various T cell subsets and their receptor expression in a cohort of 45 patients, including 27 PBC and 18 AIH cases. Both diseases exhibited T cell exhaustion and senescence along with a surge in inflammatory cytokines. Significantly increased CD38+HLA-DR+CD8+ T cell populations were observed in both diseases. AIH was characterized by an upregulation of CD8+ terminally differentiated T, CD4+ effector memory T, and CD4+ terminally differentiated T cells, and a concurrent reduction in regulatory T cells. In contrast, PBC displayed a pronounced presence of T follicular helper (Tfh) cells and a contraction of CD4-CD8- T cell populations. Correlation analysis revealed that NKP46+ natural killer frequency was closely tied to alanine aminotransferase and aspartate aminotransferase levels, and TIGIT expression on T cells was associated with globulin level in AIH. In PBC, there is a significant correlation between Tfh cells and ALP levels. Moreover, the identified immune landscapes in both diseases strongly related to disease severity. Through logistic regression analysis, γδ T, TIGIT+Vδ2 T, and Tfh1 cell frequencies emerged as distinct markers capable of differentiating PBC from AIH. In conclusion, our analyses reveal that PBC and AIH share similarities and differences regarding to immune profiles. γδ T, TIGIT+Vδ2 T, and Tfh1 cell frequencies are potential noninvasive immunological markers that can differentiate PBC from AIH.

Modulation of Tumor-Associated Macrophages to Overcome Immune Suppression in the Hepatocellular Carcinoma Microenvironment

Hepatocellular carcinoma (HCC) is a major global health issue characterized by poor prognosis and complex tumor biology. One of the critical components of the HCC tumor microenvironment (TME) is tumor-associated macrophages (TAMs), which play a pivotal role in modulating tumor growth, immune evasion, and metastasis. Macrophages are divided into two major subtypes: pro-inflammatory M1 and anti-inflammatory M2, both of which may exist in TME with altered function and proportion. The anti-inflammatory M2 macrophages are further subdivided into four distinct immune suppressive subsets. TAMs are generally counted as M2-like macrophages with altered immune suppressive functions that exert a significant influence on both cancer progression and the ability of tumors to escape immune surveillance. Their involvement in modulating immune responses via different mechanisms at the local and systemic levels has made them a key target for therapeutic interventions seeking to enhance treatment outcomes. How TAMs' depletion influences immune responses in cancer is the primary interest in cancer immunotherapies. The purpose of this review is to delve into the recent progress made in TAM-targeting therapies. We will explore the current theories, benefits, and challenges associated with TAMs' depletion or inhibition. The manuscript concludes with future directions and potential implications for clinical practice.

Single-cell transcriptomics reveals tumor microenvironment changes and prognostic gene signatures in hepatocellular carcinoma

BACKGROUND

Hepatocellular Carcinoma (HCC) is the most common type of primary liver cancer, accounting for the majority of liver cancer cases. Hepatocellular Carcinoma not only exhibits high heterogeneity but also possesses an immune-suppressive tumor microenvironment that promotes tumor evasion, posing substantial difficulties for efficient therapy. Our aim is to utilize single-cell RNA transcriptome data to investigate the dynamic changes in the tumor microenvironment during the malignant progression of HCC, the communication among immune cells, and the marker genes associated with patient prognosis.

METHODS

We constructed expression matrices from open single-cell RNA transcriptome data (GSE149614) of HCC patients (representing stages I-IV), establishing single-cell RNA transcriptional atlases for different stages of HCC progression. For each stage, we conducted cell subgroup analysis to identify cell types at each stage. Horizontally, we explored the dynamic changes of the same cell type across different stages, performing trajectory analysis and prognosis analysis. Vertically, we investigated pairwise comparisons of different stages of HCC progression, probing the dynamic alterations in tumor microenvironment immune cell signaling pathways. Finally, potential drugs for the treatment of HCC were predicted based on relevant genes.

FINDINGS

As the HCC advances towards increased malignancy, there is a shift in the predominant composition of the tumor microenvironment, with a decline in the dominance of hepatic cells. Tumor-infiltrating immune cells migrate and accumulate within the tumor microenvironment, where T cells and myeloid cells display distinct patterns of change. Genes associated with cancer-associated fibroblasts (CAFs) and T cells are correlated with adverse patient outcomes. In the late stages of HCC, the tumor microenvironment is infiltrated by more myeloid-derived suppressor cells (MDSCs), and a prognostic model constructed based on genes related to myeloid cells can predict patient outcomes. Additionally, in the analysis of transcription factors, YY1 and MYC are found to be highly expressed. Cell communication analysis among tumor-infiltrating immune cells reveals significant differences in the main signaling pathways at different stages of HCC progression. Finally, drug sensitivity analysis based on key genes identifies Acetalax, Allopurinol, and Amonafide as potential candidates for HCC treatment.

Insight of immune checkpoint inhibitor related myocarditis

As the understanding of immune-related mechanisms in the development and progression of cancer advances, immunotherapies, notably Immune Checkpoint Inhibitors (ICIs), have become integral in comprehensive cancer treatment strategies. ICIs reactivate T-cell cytotoxicity against tumors by blocking immune suppressive signals on T cells, such as Programmed Death-1 (PD-1) and Cytotoxic T-lymphocyte Antigen-4 (CTLA-4). Despite their beneficial effects, ICIs are associated with immune-related adverse events (irAEs), manifesting as autoimmune side effects across various organ systems. A particularly alarming irAE is life-threatening myocarditis. This rare but severe side effect of ICIs leads to significant long-term cardiac complications, including arrhythmias and heart failure, and has been observed to have a mortality rate of up to 50% in affected patients. This greatly limits the clinical application of ICI-based immunotherapy. In this review, we provide a comprehensive summary of the current knowledge regarding the diagnosis and management of ICI-related myocarditis. We also discuss the utility of preclinical mouse models in understanding and addressing this critical challenge.

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.

Lactylation-driven TNFR2 expression in regulatory T cells promotes the progression of malignant pleural effusion

BACKGROUND

Although tumor necrosis factor receptor 2 (TNFR2) has been recognized as an attractive next-generation candidate target for cancer immunotherapy, the factors that regulate the gene expression and their mechanistic effects on tumor-infiltrating regulatory T cells (Treg cells) remain poorly understood.

METHODS

Single-cell RNA sequencing analysis was employed to analyze the phenotypic and functional differences between TNFR2+ Treg cells and TNFR2- Treg cells. Malignant pleural effusion (MPE) from humans and mouse was used to investigate the potential mechanisms by which lactate regulates TNFR2 expression.

RESULTS

Treg cells with high TNFR2 expression exhibited elevated levels of immune checkpoint molecules. Additionally, the high expression of TNFR2 on Treg cells was positively correlated with a poor prognosis in MPE patients. Moreover, we revealed that lactate upregulated TNFR2 expression on Treg cells, thereby enhancing their immunosuppressive function in MPE. Mechanistically, lactate modulated the gene transcription of transcription factor nuclear factor-κB p65 (NF-κB p65) through histone H3K18 lactylation (H3K18la), subsequently upregulating the gene expression of TNFR2 and expediting the progression of MPE. Notably, lactate metabolism blockade combined with immune checkpoint blockade (ICB) therapy effectively enhanced the efficacy of ICB therapy, prolonged the survival time of MPE mice, and improved immunosuppression in the microenvironment of MPE.

CONCLUSIONS

The study explains the mechanism that regulates TNFR2 expression on Treg cells and its function in MPE progression, providing novel insights into the epigenetic regulation of tumor development and metabolic strategies for MPE treatment by targeting lactate metabolism in Treg cells.

Nanobodies as innovative immune checkpoint modulators: advancing cancer immunotherapy

The immune system relies on a delicate balance between attacking harmful pathogens and preserving the body's own tissues, a balance maintained by immune checkpoints. These checkpoints play a critical role in preventing autoimmune diseases by restraining excessive immune responses while allowing the immune system to recognize and destroy abnormal cells, such as tumors. In recent years, immune checkpoint inhibitors (ICIs) have become central to cancer therapy, enabling the immune system to target and eliminate cancer cells that evade detection. Traditional antibodies, such as IgGs, have been widely used in immune therapies but are limited by their size and complexity. Nanobodies (Nbs), derived from camelid heavy-chain-only antibodies, offer a promising alternative. These small, stable antibody fragments retain the antigen-binding specificity of traditional antibodies but have enhanced solubility and the ability to target otherwise inaccessible epitopes. This review explores the use of Nbs as ICIs, emphasizing their potential in cancer immunotherapy and other immune-related treatments. Their unique structural properties and small size make Nbs highly effective tools for modulating immune responses, representing a novel approach in the evolving landscape of checkpoint inhibitor therapies.

Progress of Immune Checkpoint Inhibitors Therapy for pMMR/MSS Metastatic Colorectal Cancer

Immunotherapy is one of the research hotspots in colorectal cancer field in recent years. The colorectal cancer patients with mismatch repair-deficient (dMMR) or high microsatellite instability (MSI-H) are the primary beneficiaries of immunotherapy. However, the vast majority of colorectal cancers are mismatch repair proficient (pMMR) or microsatellite stability (MSS), and their immune microenvironment is characterized by "cold tumors" that are generally insensitive to single immunotherapy based on immune checkpoint inhibitors (ICIs). Studies have shown that some pMMR/MSS colorectal cancer patients regulate the immune microenvironment by combining other treatments, such as multi-target tyrosine kinase inhibitors, anti-vascular endothelial growth factor (VEGF) monoclonal antibodies, chemotherapy, radiotherapy, anti-epithelial growth factor receptor (EGFR) monoclonal antibodies, and mitogen-activated protein kinase (MAPK) signaling pathway inhibitors and oncolytic viruses, etc. to transform "cold tumor" into "hot tumor", thereby improving the response to immunotherapy. In addition, screening for potential prognostic biomarkers can also enrich the population benefiting from immunotherapy for microsatellite stable colorectal cancer. Therefore, in pMMR or MSS metastatic colorectal cancer (mCRC), the optimization of immunotherapy regimens and the search for effective efficacy prediction biomarkers are currently important research directions. In this paper, we review the progress of efficacy of immunotherapy (mainly ICIs) in pMMR /MSS mCRC, challenges and potential markers, in order to provide research ideas for the development of immunotherapy for mCRC.

HIV infection is associated with compromised tumor microenvironment adaptive immune reactivity in Hodgkin lymphoma

ABSTRACT

The impact of HIV infection on the tumor microenvironment (TME) of classic Hodgkin lymphoma (cHL), one of the most common comorbidities after HIV infection, is not well understood. Here, we have used multiplexed immunofluorescence and spatial transcriptomic analysis to dissect the impact of viral infections (Epstein-Barr virus [EBV] and HIV/EBV) on cHL TME. HIV-EBV+ cHL TME was characterized by higher cell densities of CD8high T cells coexpressing inhibitory receptors (PD-1 and TIGIT), macrophage subsets, and an in situ inflammatory molecular profile associated with increased expression of T-cell receptor (TCR) and B-cell receptor cell signaling pathways than HIV-EBV- cHL TME. Compared with HIV-EBV+, HIV+EBV+ cHL TME was characterized by significantly less CD8high T cells coexpressing PD-1 and TIGIT, a profile concomitant with significantly increased cell densities of CD155high neoplastic cells. Significant downregulation of in situ TCR signaling and upregulation of extracellular matrix reorganization pathways were found in HIV+EBV+ cHL TME, in line with an altered topological organization of CXCL13 and heparan sulfate, an extracellular matrix glycosaminoglycan. Our data reveal the complexity of the cellular and molecular composition of cHL TME in the presence of viral infections, with possible implications for combinatorial immunotherapies. Furthermore, the data suggest specific molecular targets and pathways for further investigation that could improve our understanding of possible mechanistic links between HIV and lymphomagenesis.

CD8+ T cell exhaustion in the tumor microenvironment of breast cancer

CD8+ T cells are crucial cytotoxic components of the tumor immune system. In chronic inflammation, they become low-responsive, a state known as T cell exhaustion (TEX). The aim of immune checkpoint blockade is to counteract TEX, yet its dynamics in breast cancer remain poorly understood. This review defines CD8+ TEX and outlines its features and underlying mechanisms. It also discusses the primary mechanisms of CD8+ TEX in breast cancer, covering inhibitory receptors, immunosuppressive cells, cytokines, transcriptomic and epigenetic alterations, metabolic reprogramming, and exosome pathways, offering insights into potential immunotherapy strategies for breast cancer.

Immune alterations and overexpression of CTCF in endometrial carcinoma: insights from molecular subtyping

BACKGROUND

Endometrial cancer (EC) is a prevalent epithelial malignancy originating in the female endometrium, and its global incidence has been on the rise over the past decade. Despite significant scientific progress has been achieved recently, the genetic factors underlying EC pathogenesis remain poorly understood, warranting further investigation.

METHODS

We employed transcriptomic datasets from the Genomic Data Commons database to extract variable and clinical data. Quantile normalization and log2 transformations were applied to obtain a gene expression matrix for the sample cohort. Various assays, such as quantitative real-time polymerase chain reaction (qRT-PCR), western blotting, immunohistochemistry (IHC), wound healing assay, transwell assay, and TUNEL assay, were employed in the study to examine the involvement of CTCF in EC cell biology. Additionally, in vivo experiments were conducted using a subcutaneous transplantation tumor model in athymic nude mice. The potential mechanism of action of CTCF was also illustrated by identifying differentially expressed genes (DEGs) and functions after interfering with CTCF gene expression through the GSPAdb online database.

RESULTS

After categorizing 543 samples into cohorts with high and low ImmuneScores, we discovered 1025 genes that were differentially expressed, including 745 genes that were up-regulated and 280 genes that were down-regulated in the high scores group compared to the low scores group. Tumor mutation burden (TMB) analysis highlighted 11 genes with the highest mutation frequency. Furthermore, 16 immune checkpoints and 50 immune regulatory factors exhibited differential expression. Among these, CTCF was up-regulated in EC. We found that CTCF knockdown could diminish EC's invasive ability and metastatic potential while enhancing apoptosis. In vivo experiments corroborated that CTCF knockdown could reduce tumor growth. The GSPAdb online database identified differential expression pathways mainly enriched in cellular metabolism as well as some intracellular classical signaling pathways after interfering with CTCF gene expression. In addition, we identified potential downstream regulators of CTCF through protein interaction networks.

CONCLUSION

This study unveiled comprehensive molecular characteristics and DEGs in EC, emphasizing the up-regulation of CTCF in EC. Our findings collectively suggest that CTCF represents a promising therapeutic target, and our gene molecular typing model offers a novel approach for prognostic evaluation in EC.

TIGIT: Will it be the next star therapeutic target like PD-1 in hematological malignancies?

Research on the mechanism and application of checkpoint inhibitory receptors in hematologic diseases has progressed rapidly. However, in the treatment of relapserefractory (R/R) hematologic malignancies and anti-programmed cell death protein 1 (PD-1), patients who are resistant to anti-cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) are in urgent need of alternative therapeutic targets. T cell immunoreceptor with immunoglobulin and ITIM domains (TIGIT) has a broad prospect as an inhibitory receptor like PD-1, but its more specific mechanism of action and application in hematologic diseases still need to be further studied. In this review, we discuss the mechanism of TIGIT pathway, combined effects with other immune checkpoints, immune-related therapy, the impact of TIGIT on hematopoietic stem cell transplantation (HSCT) and the tumor microenvironment (TME) provides a potential therapeutic target for hematologic malignancies.

Emerging druggable targets for immune checkpoint modulation in cancer immunotherapy: the iceberg lies beneath the surface

The immune system serves as a fundamental defender against the initiation and progression of cancer. Failure of the immune system augments immunosuppressive action that leading to cancer manifestation. This immunosuppressive effect causes from significant alterations in immune checkpoint expression associated with tumoral progression. The tumor microenvironment promotes immune escape mechanisms that further amplifying immunosuppressive actions. Notably, substantial targeting of immune checkpoints has been pragmatic in the advancement of cancer research. This study highlights a comprehensive review of emerging druggable targets aimed at modulating immune checkpoint co-inhibitory as well as co-stimulatory molecules in response to immune system activation. This modulation has prompted to the development of newer therapeutic insights, eventually inducing immunogenic cell death through immunomodulatory actions. The study emphasizes the role of immune checkpoints in immunogenic regulation of cancer pathogenesis and explores potential therapeutic avenues in cancer immunotherapy.Modulation of Immunosuppressive and Immunostimulatory pathways of immune checkpoints in cancer immunotherapy.

Immune Checkpoints Are New Therapeutic Targets in Regulating Cardio-, and Cerebro-Vascular Diseases and CD4+Foxp3+ Regulatory T Cell Immunosuppression

Although previous reviews explored the roles of selected immune checkpoints (ICPs) in cardiovascular diseases (CVD) and cerebrovascular diseases from various perspectives, many related aspects have yet to be thoroughly reviewed and analyzed. Our comprehensive review addresses this gap by discussing the cellular functions of ICPs, focusing on the tissue-specific and microenvironment-localized transcriptomic and posttranslational regulation of ICP expressions, as well as their functional interactions with metabolic reprogramming. We also analyze how 14 pairs of ICPs, including CTLA-4/CD86-CD80, PD1-PDL-1, and TIGIT-CD155, regulate CVD pathogenesis. Additionally, the review covers the roles of ICPs in modulating CD4+Foxp3+ regulatory T cells (Tregs), T cells, and innate immune cells in various CVDs and cerebrovascular diseases. Furthermore, we outline seven immunological principles to guide the development of new ICP-based therapies for CVDs. This timely and thorough analysis of recent advancements and challenges provide new insights into the role of ICPs in CVDs, cerebrovascular diseases and Tregs, and will support the development of novel therapeutics strategies for these diseases.

TIGIT expression on neoplastic cells is a poor prognostic factor for adult T-cell leukaemia/lymphoma

Adult T-cell leukaemia/lymphoma (ATLL) is an aggressive peripheral T-cell neoplasm with a poor prognosis. T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domains (TIGIT) is an immune checkpoint receptor expressed on T and natural killer cells. Although increased TIGIT expression in the tumour microenvironment is associated with poor prognosis in various neoplasms, its relevance in ATLL remains unknown. Herein, we investigated the clinicopathological impact of TIGIT expression on ATLL using immunohistochemistry. TIGIT expression was detected in 21 of 84 patients (25%). A partial association between the clinical features and immune checkpoint molecules and the expression of TIGIT was found including sIL-2R, CD86 and GITR. TIGIT-positive patients [median survival time (MST) 8.9 months, 95% confidence interval (CI) 7.7-15.6] had inferior overall survival compared with TIGIT-negative patients (MST 18.7 months, 95% CI 12.0-36.4) (p=0.0124]. TIGIT expression maintained its prognostic value for overall survival in both univariate and multivariate analyses [hazard ratio (HR) 1.909; 95% CI 1.044-3.488; p=0.0356]. Further studies are required to clarify the clinical and biological significance of TIGIT expression in patients with ATLL.