Immune checkpoint modulators in cancer immunotherapy: recent advances and emerging concepts

Biological mechanisms and immunotherapy of brain metastases in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related mortality worldwide, with Brain Metastases serving as a significant adverse prognostic factor. The blood-brain barrier poses a substantial challenge in the treatment of brain metastases, as it restricts the penetration of many anticancer agents. Novel immunotherapy, such as immune checkpoint inhibitors (ICIs) have emerged as promising treatment for NSCLC and its associated brain metastases. This review summarizes the biological mechanism underlying NSCLC brain metastases and provides an overview of the current landscape of immunotherapy, exploring the mechanism of action and clinical applications of these advanced treatments.

The next generation of immunotherapies for lung cancers

Immunotherapies, specifically immune-checkpoint inhibitors (ICIs) targeting PD-(L)1 or CTLA4, have revolutionized the treatment of lung cancer; however, many patients do not have a response to ICIs and most of those with an initial tumour response eventually have disease progression owing to acquired resistance. Over the past few years, numerous therapeutic strategies have been explored to address the problems of intrinsic and acquired resistance to ICIs. In 2024, regulatory approvals of the bispecific PD-1 × VEGF antibody ivonescimab for the treatment of non-small-cell lung cancer in China and the bispecific DLL3 × CD3 T cell engager tarlatamab for patients with small cell lung cancer in the USA provided clinical proof-of-concept for overcoming the challenge of ICI resistance using novel immunotherapeutic agents, thereby increasing enthusiasm for the exploration of next-generation immunotherapies for lung cancer. A large variety of immunotherapies with diverse targets and mechanisms of action are currently being tested in clinical trials involving patients with lung cancer. In this Review, we provide an overview of these emerging immunotherapies in clinical development for non-small-cell lung cancer and/or small cell lung cancer, including novel immune-checkpoint modulators, immune cell engagers, adoptive cell therapies and therapeutic cancer vaccines. We describe the designs of these agents and the mechanisms by which they might overcome resistance to the current generation of ICIs. We also discuss hurdles impeding the clinical translation of each immunotherapeutic modality and potential strategies to address these challenges, using representative examples of agents that have entered the later phases of clinical testing.

Discovery of Orally Potent Small-Molecule CD73 Inhibitor for Cancer Immunotherapy

CD73, an emerging immune checkpoint, plays a pivotal role in the adenosine (ADO) metabolic pathway by catalyzing the conversion of AMP to ADO. This process has been shown to inhibit the functions of T cells and natural killer (NK) cells, thereby exacerbating the immunosuppressive effects within the tumor microenvironment. These findings underscore the critical role of CD73 in modulating immune cell function and represent a promising therapeutic target for cancer treatment. Herein, a series of novel CD73 inhibitors featuring a 1H,3H-dihydro-2,4-pyrimidinone moiety was achieved. Notably, XC-12 exhibited potent in vitro anti-CD73 activity against both soluble and membrane-bound forms (IC50 = 12.36 and 1.29 nM, respectively). Furthermore, XC-12 was orally bioavailable and significantly inhibited the tumor growth in the CT26 syngeneic mouse model (TGI: 74%) at a dose of 135 mg/kg. These results suggest that XC-12 may serve as a promising candidate for cancer immunotherapy.

Clinical study of adebrelimab in combination with apatinib and irinotecan for PD-1 inhibitor-ineffective advanced-stage gastric cancer: study protocol for a single-arm, single-centre, exploratory trial

INTRODUCTION

Immunotherapy has revolutionised cancer treatment. Immune checkpoint inhibitors have demonstrated significant efficacy across multiple tumour types, including gastric cancer, where several approved programmed cell death 1/programmed cell death-ligand 1 (PD-1/PD-L1) inhibitors show promising antitumour activity. While PD-L1 expression serves as a predictive biomarker for PD-1 inhibitor response, and PD-L1-positive patients generally show better outcomes, therapeutic resistance remains a challenge. Many initial responders eventually develop resistance, and surprisingly, some PD-L1-positive patients fail to achieve expected response rates, indicating emerging resistance mechanisms in potentially responsive populations. Adebrelimab, a PD-L1 inhibitor, demonstrates mechanistic advantages over PD-1 inhibitors, with clinical studies suggesting promising therapeutic potential. When combined with irinotecan, apatinib has shown efficacy in second-line gastric cancer treatment. This study aims to evaluate the efficacy and safety of combining adebrelimab with apatinib and irinotecan for advanced gastric cancer refractory to PD-1 inhibitors.

METHOD AND ANALYSIS

This single-arm, single-centre exploratory trial will be conducted at Renji Hospital, enrolling 32 patients aged 18-75 years. Eligible patients must have initially achieved partial response, complete response or stable disease with progression-free survival (PFS)≥3 months during prior immunotherapy but subsequently progressive disease on imaging. Treatment will continue until meeting discontinuation criteria. The primary endpoint is objective response rate with Clopper-Pearson 95% CI. Secondary endpoints include disease control rate (95% CI), PFS and overall survival (estimated by Kaplan-Meier method), along with safety assessments.

ETHICS AND DISSEMINATION

All participants will provide informed consent. The protocol has been approved by the Shanghai Jiaotong University School of Medicine, Renji Hospital Ethics Committee (LY2023-201-C). The results will be disseminated through peer-reviewed manuscripts, reports and presentations.

TRIAL REGISTRATION NUMBER

ChiCTR2300077329.

Bone marrow microenvironment in myelodysplastic neoplasms: insights into pathogenesis, biomarkers, and therapeutic targets

Myelodysplastic neoplasms (MDS) represent a heterogeneous group of malignant hematopoietic stem and progenitor cell (HSPC) disorders characterized by cytopenia, ineffective hematopoiesis, as well as the potential to progress to acute myeloid leukemia (AML). The pathogenesis of MDS is influenced by intrinsic factors, such as genetic insults, and extrinsic factors, including altered bone marrow microenvironment (BMM) composition and architecture. BMM is reprogrammed in MDS, initially to prevent the development of the disease but eventually to provide a survival advantage to dysplastic cells. Recently, inflammation or age-related inflammation in the bone marrow has been identified as a key pathogenic mechanism for MDS. Inflammatory signals trigger stress hematopoiesis, causing HSPCs to emerge from quiescence and resulting in MDS development. A better understanding of the role of the BMM in the pathogenesis of MDS has opened up new avenues for improving diagnosis, prognosis, and treatment of the disease. This article provides a comprehensive review of the current knowledge regarding the significance of the BMM to MDS pathophysiology and highlights recent advances in developing innovative therapies.

Evaluation of surrogate endpoints in phase III randomized control trials of advanced hepatocellular carcinoma treated with immune checkpoint inhibitors

PURPOSE

Overall survival (OS) is recommended as a gold standard endpoint but has some limitations. We aimed to finding more effective surrogate endpoints for advanced hepatocellular carcinoma (HCC) treated with immune checkpoint inhibitors (ICIs).

METHODS

Three online databases were searched for randomized control trials (RCTs) on HCC, published between January 2015 and July 2023, that evaluated ICIs and reported progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and OS. The correlation between the potential surrogate endpoints and OS was evaluated at the trial, arm, and patient levels. The prediction models were validated in single-arm or non-RCTs. Individual data were collected from a real-world (RW) cohort with advanced HCC underwent ICI monotherapy at three tertiary medical centers in China.

RESULTS

Ten RCTs (6023 participants) with 11 comparisons were included. PFS had a moderately significant association with OS (R2 = 0.50, p = 0.014). ORR, DCR, and OS showed weak correlations. On limiting the analysis to ICI monotherapy studies, the correlations of OS with PFS became stronger (R2 = 0.85, p = 0.02). The RW cohort also verified that PFS was closely related to OS when patient received with ICI monotherapy.

CONCLUSION

PFS are recommended as surrogate markers in patients with advanced HCC treated with ICI monotherapy.

Role of Tumor-Associated Macrophages in Breast Cancer Immunotherapy

Breast cancer (BC) is the second leading cause of death among women worldwide. Immunotherapy has become an effective treatment for BC patients due to the rapid development of medical technology. Considerable breakthroughs have been made in research, marking the beginning of a new era in cancer treatment. Among them, various cancer immunotherapies such as immune checkpoint inhibitors (ICIs), cancer vaccines, and adoptive cell transfer are effective and have good prospects. The tumor microenvironment (TME) plays a crucial role in determining the outcomes of tumor immunotherapy. Tumor-associated macrophages (TAMs) are a key component of the TME, with an immunomodulatory effect closely related to the immune evasion of tumor cells, thereby affecting malignant progression. TAMs also significantly affect the therapeutic effect of ICIs (such as programmed death 1/programmed death ligand 1 (PD-1/PD-L1) inhibitors). TAMs are composed of multiple heterogeneous subpopulations, including M1 phenotypes macrophages (M1) and M2 phenotypes macrophages (M2). Furthermore, they mainly play an M2-like role and moderate a variety of harmful consequences such as angiogenesis, immunosuppression, and metastasis. Therefore, TAMs have become a key area of focus in the development of tumor therapies. However, several tumor immunotherapy studies demonstrated that ICIs are effective only in a small number of solid cancers, and tumor immunotherapy still faces relevant challenges in the treatment of solid tumors. This review explores the role of TAMs in BC immunotherapy, summarizing their involvement in BC development. It also explains the classification and functions of TAMs, outlines current tumor immunotherapy approaches and combination therapies, and discusses the challenges and potential strategies for TAMs in immuno-oncology treatments.

Harnessing Oncolytic Viruses for Targeted Therapy in Triple-Negative Breast Cancer

Breast cancer is the most prevalent malignant tumor among women, with triple-negative breast cancer (TNBC) being one of the most aggressive forms due to its high invasiveness and metastatic potential. Traditional treatments such as endocrine therapy and anti-HER2-targeted therapy are largely ineffective for TNBC, and while chemotherapy shows some promise, resistance remains a significant hurdle. Recently, there has been increasing interest in biological therapies, especially oncolytic viruses (OVs). OVs promote anti-tumor effects by selectively killing tumor cells and stimulating immune responses, and have achieved notable breakthroughs in breast cancer treatment. OVs have demonstrated effectiveness comparable to surgery, radiotherapy, or chemotherapy in selected cancers, but data are sparse in the context of TNBC. This review provides an overview of recent progress in the application of OVs as a tool for precision TNBC treatment.

Ultra-low dose immunoPET using 64Cu-rituximab tracer for a human CD20 mouse model

Antibodies (Abs) and their fragments can be labeled with PET radioisotope (immunoPET) for in vivo diagnostic imaging. Compared to the conventional FDG-PET, immunoPET can be designed to target in vivo cancer-specific antigen expression levels for various tumors and metastasis, which makes immunoPET (iPET) a powerful technique for molecular imaging and therapy monitoring. However, achieving the optimal dose to minimize radioisotope toxicity without compromising the visualization of the smallest tumor is challenging. To find an ultra-minimal tracer dose, we have developed a novel iPET with an intact rituximab Ab labeled with 64Cu to image human CD20 (hCD20) in a transgenic mouse model for non-Hodgkin's lymphoma (NHL) imaging. Using phantom and in vivo mouse models, we optimized the minimal dose that can be administered in a mouse using a high-specific iPET tracer prepared from 64Cu-rituximab. A phantom study was used to characterize the scanner capability and limit for imaging using low doses. An ultra-minimal dose administered in a mouse model showed good image quality with high signal-to-noise ratio without compromising quantitative accuracy. The phantom study with below 50 μCi dose level indicated a slight increase in variability due to reduced dose specifically for target regions with lower uptakes (<3:1 ratio) relative to the background. In vivo study performed with four groups of mice (n = 3), each group injected with ~90, ~50, ~25, and ~10 μCi showed a linear increase of tracer uptake measured as percentage injected dose per gram (%ID/g). This tracer has shown high specific uptake in the spleen, where most B-cells are engineered to express hCD20. The study demonstrated that the lowest dose threshold limit for 64Cu-antibody-based iPET was about 25 μCi while achieving a high-quality image and quantitative accuracy.

The Benefits and Safety of Monoclonal Antibodies: Implications for Cancer Immunotherapy

Monoclonal antibodies (mAbs) have transformed cancer treatment by providing highly targeted and effective therapies that specifically attack cancer cells, thus reducing the likelihood of adverse events (AEs) in patients. mAbs exert their action through various mechanisms, such as receptor blockade, antibody-dependent cellular cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), and inhibition of immune checkpoints (eg, PD-1, PD-L1, and CTLA-4). These therapies have led to significant improvements in the treatment of several cancers, including HER2-positive breast cancer, non-small cell lung cancer (NSCLC), and melanoma. The efficacy of mAb therapy in cancer treatment is influenced by various intrinsic and extrinsic factors, such as environmental exposures, psychosocial factors, infection status, ways of life, and tumor microenvironment (TME), all of which can impact immune responses and treatment outcomes. Notably, the therapeutic benefits of mAbs are often accompanied by immune-related AEs (irAEs), which can vary from mild to severe and affect multiple organ systems. The dual nature of mAbs-stimulating antitumor immune responses while also inducing immune-related side effects-presents a notable challenge in clinical practice. This review highlights the importance of proactive strategies for managing irAEs, such as early detection, corticosteroid use, targeted immunosuppressive treatments, and the urgent need for reliable predictive biomarkers to improve treatment outcomes. Advancements in the prevention, prediction, and management of irAEs are essential to enhance the safety and effectiveness of mAb-based therapies, ultimately aiming to improve cancer patient outcomes.

CD47 Knock-Out Using CRISPR-Cas9 RNA Lipid Nanocarriers Results in Reduced Mesenchymal Glioblastoma Growth In Vivo

Immune checkpoint (ICP) blockade has shown limited effectiveness in glioblastoma (GBM), particularly in the mesenchymal subtype, where interactions between immune cells and glioblastoma cancer stem cells (GSCs) drive immunosuppression and therapy resistance. Tailoring ICPs specific to GSCs can enhance the antitumor immune response. This study proposes the use of lipid nanoparticles (LNPs) encapsulating CRISPR RNAs as an in vivo screening tool for ICPs in a syngeneic model of mesenchymal GSCs. Using PD-L1 and CD47 to validate the proof of concept, intratumoral administration of LNPs in orthotopic tumors achieved efficient editing of ICPs, leading to enhanced immune cell infiltration within the tumor microenvironment. Targeting CD47 reduced tumor growth, suggesting improved cancer cell sensitization to the immune system post-ICP editing. The study positions LNPs as a robust tool for in vivo validation of ICPs as therapeutic targets in clinically relevant GBM models. LNPs could serve as a screening tool in patient-derived xenografts to identify and optimize ICP combinations, potentially expediting ICP translation and enhancing personalized GBM immunotherapies.

Pembrolizumab-induced Guillain-Barré syndrome in triple-negative breast cancer: A case report

BACKGROUND

The programmed cell death protein 1 inhibitor pembrolizumab has become a key treatment for various cancers, including triple-negative breast cancer. However, it is associated with immune-related adverse events, including rare but serious neurological complications such as Guillain-Barré syndrome (GBS). GBS is a potentially life-threatening autoimmune disorder characterized by muscle weakness and paralysis. We present a unique case of pembrolizumab-induced GBS to highlight the importance of recognizing this complication and managing it promptly in patients receiving immune checkpoint inhibitors.

CASE SUMMARY

A 69-year-old woman with a medical history of hypertension, anxiety, depression, and stage IIIB triple-negative breast cancer treated with pembrolizumab, carboplatin, and paclitaxel, presented to the emergency department with a 1-month history of tingling, lower extremity weakness, and shooting pain. Symptoms progressed to global weakness, ascending paralysis, and double vision. Neurological examination revealed significant lower extremity weakness and sensory deficits. Magnetic resonance imaging of the lumbar spine and cerebrospinal fluid analysis confirmed GBS. Initial treatment with intravenous immunoglobulin led to relapse, requiring additional intravenous immunoglobulin and high-dose glucocorticoids. The patient's condition improved, pembrolizumab therapy was permanently discontinued, and she was discharged to a rehabilitation facility.

CONCLUSION

Pembrolizumab can induce GBS, necessitating early recognition, prompt diagnosis, and multidisciplinary management to prevent serious complications.

Triple-Negative Breast Cancer Systemic Treatment: Disruptive Early-Stage Developments for Overcoming Stagnation in the Advanced Pipeline

New breast cancer (BC) diagnoses will soon reach 2.5-3 million/year worldwide, with 15-25% of them being triple-negative breast cancer (TNBC), the most aggressive type, characterized for lacking the main pharmacological targets: estrogen and progesterone receptors (ERs and PRs), as well as HER2 overexpression. Therefore, chemotherapy remains the almost-unique systemic treatment for TNBC. However, some targeted therapies are recommended for use in combination with chemotherapy; namely, PARP inhibitors for BRCA-mutated TNBC, the immune checkpoint inhibitors pembrolizumab and atezolizumab, as well as the antibody-drug conjugates sacituzumab govitecan and trastuzumab deruxtecan, the latter for HER2low subtypes. Regardless of the limited benefits they provide, other treatments with similar mechanisms of action are being investigated in advanced clinical stages. Further, therapies that benefit other cancers, like PI3K/Akt/mTOR pathway and CDK4/6 inhibitors, are still being investigated for TNBC, although convincing results have not been obtained. Given this scenario, it might appear innovation for TNBC treatments has become stuck. However, the huge unmet medical need drives intense research into the biology of the disease. As a result, emerging disruptive therapies are being tested in early-stage trials, designed for novel targets and applying cutting-edge advances in immunotherapy and precision oncology.

Tri-specific tribodies targeting 5T4, CD3, and immune checkpoint drive stronger functional T-cell responses than combinations of antibody therapeutics

One of the most promising cancer immunotherapies is based on bi-specific T-cell engagers (BiTEs) that simultaneously bind with one arm to a tumor-associated antigen on tumor cells and with the other one to CD3 complex on T cells to form a TCR-MHC independent immune synapse. We previously generated four novel tri-specific tribodies made up of a Fab targeting 5T4, an oncofetal tumor antigen expressed on several types of tumors, a scFv targeting CD3 on T cells, and an additional scFv specific for an immune checkpoint (IC), such as PD-1, PD-L1 or LAG-3. To verify their advantages over the combinations of BiTEs (CD3/TAA) with IC inhibitors, recently used to overcome tumor immunosuppressive environment, here we tested their functional properties in comparison with clinically validated mAbs targeting the same ICs, used alone or in combination with a control bi-specific devoid of immunomodulatory scFvs, called 53 P. We found that the novel tri-specific tribodies activated human peripheral blood mononuclear cells more efficiently than clinically validated mAbs (atezolizumab, pembrolizumab, and relatlimab) either used alone or in combination with 53 P, leading to a stronger tumor cytotoxicity and cytokines release. In particular, 53L10 tribody targeting PD-L1 displayed much more potent effects than the combination of 53 P with all the clinically validated mAbs and led to complete tumor regression in vivo, showing much higher efficacy than the combination of 53 P and atezolizumab. We shed light on the molecular basis of this potentiated anti-tumor activity by evidencing that the insertion of the anti-PD-L1 moiety in 53L10 led not only to stronger binding of the tri-specific to tumor cells but also efficiently blocked the effects of increased PD-L1 on tumor cells, induced by IFNγ secretion also due to T-cell activation. These results are important also for the design of novel T-cell engagers targeting other tumor antigens.

Targeting ferroptosis: a promising approach for treating lung carcinoma

Lung carcinoma incidence and fatality rates remain among the highest on a global scale. The efficacy of targeted therapies and immunotherapies is commonly compromised by the emergence of drug resistance and other factors, resulting in a lack of durable therapeutic benefits. Ferroptosis, a distinct pattern of cell death marked by the buildup of iron-dependent lipid peroxides, has been shown to be a novel and potentially more effective treatment for lung carcinoma. However, the mechanism and regulatory network of ferroptosis are exceptionally complex, and many unanswered questions remain. In addition, research on ferroptosis in the diagnosis and treatment of lung cancer has been growing exponentially. Therefore, it is necessary to provide a thorough summary of the latest advancements in the field of ferroptosis. Here, we comprehensively analyze the mechanisms underlying the preconditions of ferroptosis, the defense system, and the associated molecular networks. The potential strategies of ferroptosis in the treatment of lung carcinoma are also highlighted. Targeting ferroptosis improves tumor cell drug resistance and enhances the effectiveness of targeted drugs and immunotherapies. These findings may shed fresh light on the diagnosis and management of lung carcinoma, as well as the development of drugs related to ferroptosis.

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.

From Pioneering Discoveries to Innovative Therapies: A Journey Through the History and Advancements of Nanoparticles in Breast Cancer Treatment

Nanoparticle technology has revolutionized breast cancer treatment by offering innovative solutions addressing the gaps in traditional treatment methods. This paper aimed to comprehensively explore the historical journey and advancements of nanoparticles in breast cancer treatment, highlighting their transformative impact on modern medicine. The discussion traces the evolution of nanoparticle-based therapies from their early conceptualization to their current applications and future potential. We initially explored the historical context of breast cancer treatment, highlighting the limitations of conventional therapies, such as surgery, radiation, and chemotherapy. The advent of nanotechnology has introduced a new era characterized by the development of various nanoparticles, including liposomes, dendrimers, and gold nanoparticles, designed to target cancer cells with remarkable precision. We further described the mechanisms of action for nanoparticles, including passive and active targeting, and reviewed significant breakthroughs and clinical trials that have validated their efficacy. Current applications of nanoparticles in breast cancer treatment have been examined, showcasing clinically approved therapies and comparing their effectiveness with traditional methods. This article also discusses the latest advancements in nanoparticle research, including drug delivery systems and combination therapy innovations, while addressing the current technical, biological, and regulatory challenges. The technical challenges include efficient and targeted delivery to tumor sites without affecting healthy tissue; biological, such as potential toxicity, immune system activation, or resistance mechanisms; economic, involving high production and scaling costs; and regulatory, requiring rigorous testing for safety, efficacy, and long-term effects to meet stringent approval standards. Finally, we have explored emerging trends, the potential for personalized medicine, and the ethical and social implications of this transformative technology. In conclusion, through comprehensive analysis and case studies, this paper underscores the profound impact of nanoparticles on breast cancer treatment and their future potential.

Beyond checkpoint inhibitors: the three generations of immunotherapy

Anti-tumor immunotherapy was rediscovered and rejuvenated in the last two decades with the discovery of CTLA-4, PD-1 and PD-L1 and the roles in inhibiting immune function and tumor evasion of anti-tumor immune response. Following the approval of the first checkpoint inhibitor ipilimumab against CTLA-4 in melanoma in 2011, there has been a rapid development of tumor immunotherapy. Furthermore, additional positive and negative molecules among the T-cell regulatory systems have been identified that that function to fine tune the stimulatory or inhibitory immune cells and modulate their functions (checkpoint modulators). Many strategies are being explored to target macrophages, NK-cells, cytotoxic T-cells, fibroblasts, endothelial cells, cytokines and molecules involved in tumor tolerance and microbiome. Similar to agents that target checkpoint modulators, these newer targets have the potential to synergize with other classes of immunotherapeutic agents and importantly may overcome the resistance to other immunotherapies. In order to better understand the mechanism of action of all major classes of immunotherapy, design clinical trials taking advantage of different types of immunotherapeutic agents and use them rationally in clinical practice either in combination or in sequence, we propose the group all immunotherapies into three generations: with CTLA-4, PD-1 and PD-L1 inhibitors as the first generation, agents that target the checkpoint modulators as the second generation, while those that target TME as the third generation. This review discusses all three generations of immunotherapy in oncology, their mechanism of actions, major clinical trial results and indication, strategies for future clinical trial designs and rational clinical applications.

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.

Target therapy of TIGIT; a novel approach of immunotherapy for the treatment of colorectal cancer

The T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT), a newly discovered checkpoint, is characterized by its elevated expression on CD4 + T cells, CD8 + T cells, natural killer (NK) cells, regulatory T cells (Tregs), and tumor-infiltrating lymphocytes (TILs). Research to date has been shown that TIGIT has been linked to exhaustion of NK cell both and T cells in numerous cancers. CD155, being the specific ligand of TIGIT in humans, emerges as a key target for immunotherapy owing to its crucial interaction with TIGIT. Furthermore, numerous studies have demonstrated that the combination of TIGIT with other immune checkpoint inhibitors (ICIs) and/or traditional treatments elicits a potent antitumor response in colorectal cancer (CRC). This review provides an overview of the structure, function, and signaling pathways associated with TIGIT across multiple immune system cell types. Additionally, focusing on the role of TIGIT in the progression of CRC, this study reviewed various studies exploring TIGIT-based immunotherapy in CRC.

Diagnosis and management of immune checkpoint inhibitor-associated nephrotoxicity: a position statement from the American Society of Onco-nephrology

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of cancer and are now the backbone of therapy for several malignancies. However, ICIs can cause a spectrum of kidney immune-related adverse events including acute kidney injury (AKI), most commonly manifesting as acute interstitial nephritis (AIN), although glomerular disease and electrolyte disturbances have also been reported. In this position statement by the American Society of Onco-nephrology (ASON), we summarize the incidence and risk factors for ICI-AKI, pathophysiological mechanisms, and clinicopathologic features of ICI-AKI. We also discuss novel diagnostic approaches and promising biomarkers for ICI-AKI. From expert panel consensus, we provide clinical practice points for the initial assessment and diagnosis of ICI-AKI, management and immunosuppressive therapy, and consideration for rechallenge with ICI following AKI episodes. In addition, we explore ICI use in special populations, such as kidney transplant recipients, and propose key areas of focus for future research and clinical investigation.

A comprehensively prognostic and immunological analysis of PARP11 in pan-cancer

Poly (ADP-ribose) polymerase family member 11 (PARP11) has important immune regulatory functions in viral infection and tumor immune response. Particularly, PARP11 showed protumor activities in multiple preclinical murine models. However, no systematic pan-cancer analysis has been conducted to explore PARP11 function. In this study, we used multiple databases to assess PARP11 expression, which is associated with clinical outcomes, immune checkpoint factors, prognostic significance, genomic characteristics, and immunological aspects. The analysis revealed varying expression levels of PARP11 across different cancer types and a significant correlation between its expression and immune cell infiltration. Insights from the CellMiner database suggest a strong link between PARP11 expression and sensitivity to anticancer drugs, highlighting its potential as a therapeutic target. Moreover, PARP11 expression correlates with patient survival during anti-PD1 and anti-CTLA4 treatments, suggesting that PARP11 would be a predictor of immune checkpoint inhibitor treatment. In summary, PARP11 would be a potential immunoregulatory target and a diagnosis and prognosis marker for certain types of cancers. The detailed mechanisms of PARP11 in tumor immune responses need to be further investigated.

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.

The emerging roles of liquid-liquid phase separation in tumor immunity

Recent advancements in tumor immunotherapy, particularly PD-1 targeted therapy, have shown significant promise, marking major progress in tumor treatment approaches. Despite this, the development of resistance to therapy and mechanisms of immune evasion by tumors pose considerable obstacles to the broad application of immunotherapy. This necessitates a deeper exploration of complex immune signaling pathways integral to tumor immunity. This review aims to critically analyze the role of liquid-liquid phase separation (LLPS) within tumor immunity, specifically its impact on immune signaling pathways and its potential to foster the development of novel cancer therapies. LLPS, a biophysical process newly recognized for its ability to spontaneously segregate and organize biomacromolecules into liquid-like condensates through weak multivalent interactions, offers a novel perspective on the formation of signaling clusters and the functionality of immune molecules. The review delves into the micromolecular mechanisms behind the creation of signaling condensates via LLPS and reviews recent progress in adjusting signaling pathways pertinent to tumor immunity, including the T cell receptor (TCR), B cell receptor (BCR), immune checkpoints, and innate immune pathways such as the cGAS-STING pathway, stress granules, and the ADP-heptose-ALPK1 signaling axis. Furthermore, it considers the prospects of utilizing LLPS to generate groundbreaking cancer therapies capable of navigating past current treatment barriers. Through an extensive examination of LLPS's impact on tumor immunity, the review seeks to highlight novel therapeutic strategies and address the challenges and future directions in this rapidly evolving field.

Revolutionizing cancer treatment: the rise of personalized immunotherapies

Interest in biological therapy for cancer has surged due to its precise targeting of cancer cells and minimized impact on surrounding healthy tissues. This review discusses various biological cancer therapies, highlighting advanced alternatives over conventional chemotherapy alone. It explores DNA and RNA-based vaccines, T-cell modifications, adoptive cell transfer, CAR T cell therapy, angiogenesis inhibitors, and the combination of immunotherapy with chemotherapy, offering a holistic view of the potential in cancer treatment. Additionally, it discusses the role of nanotechnology in increasing the efficacy of cancer-targeting drugs, as well as cytokine and immunoconjugate therapies for bolstering immune system effectiveness against neoplastic cells. The potential of gene potential for precise targeting of cancer-linked genes and the application of oncolytic viruses against virus-associated cancers are also discussed. The review identifies significant advancements in the targeted treatment of cancer by biological methods. It acknowledges the challenges, including drug resistance and the need for high specificity in certain therapies, while also highlighting the effectiveness of cancer vaccines, modified T-cells, and oncolytic viruses. Biological therapies are a promising frontier in cancer treatment, offering the potential for more personalized and effective therapeutic strategies. Despite existing challenges, ongoing research and clinical trials are fundamental for overcoming current limitations and enhancing the efficacy of biological therapies in cancer care.

Discovery of small molecules for autophagy-lysosome degradation of immune checkpoint proteins

Targeted protein degradation (TPD) technologies, particularly proteolysis targeting chimeras (PROTACs), have emerged as a promising branch of targeted therapy. Current ubiquitin-proteasome-dependent TPD technologies are limited to targeting intracellular proteins. Although the blockade of immune checkpoints has achieved great clinical success, most immune checkpoints are transmembrane proteins, which are difficult to be ubiquitinated and degraded by PROTACs. Herein, we developed a novel discovery strategy of bifunctional small molecules, which could mediate autophagy-lysosome degradation of immune checkpoints. F-1 was demonstrated to activate the autophagy-lysosome system, and conjugation of F-1 with inhibitors targeting programmed cell death-ligand 1 (PD-L1) or V-domain Ig suppressor of T-cell activation (VISTA) generated a new class of small molecules that effectively induce the degradation of PD-L1 or VISTA in tumor cells. The most promising PD-L1 degrader B3 significantly induced PD-L1 degradation in RKO cells through the autophagy-lysosome system and exhibited good tumor-inhibiting effects in vivo. Our work could expand the development of degraders targeting immune checkpoints and provide a promising discovery strategy for future autophagy-lysosome targeting degradation technology.

Network-based drug repurposing identifies small molecule drugs as immune checkpoint inhibitors for endometrial cancer

Endometrial cancer (EC) is the 6th most common cancer in women around the world. Alone in the United States (US), 66,200 new cases and 13,030 deaths are expected to occur in 2023 which needs the rapid development of potential therapies against EC. Here, a network-based drug-repurposing strategy is developed which led to the identification of 16 FDA-approved drugs potentially repurposable for EC as potential immune checkpoint inhibitors (ICIs). A network of EC-associated immune checkpoint proteins (ICPs)-induced protein interactions (P-ICP) was constructed. As a result of network analysis of P-ICP, top key target genes closely interacting with ICPs were shortlisted followed by network proximity analysis in drug-target interaction (DTI) network and pathway cross-examination which identified 115 distinct pathways of approved drugs as potential immune checkpoint inhibitors. The presented approach predicted 16 drugs to target EC-associated ICPs-induced pathways, three of which have already been used for EC and six of them possess immunomodulatory properties providing evidence of the validity of the strategy. Classification of the predicted pathways indicated that 15 drugs can be divided into two distinct pathway groups, containing 17 immune pathways and 98 metabolic pathways. In addition, drug-drug correlation analysis provided insight into finding useful drug combinations. This fair and verified analysis creates new opportunities for the quick repurposing of FDA-approved medications in clinical trials.

Euphorbia Pekinensis Rupr. sensitizes colorectal cancer to PD-1 blockade by remodeling the tumor microenvironment and enhancing peripheral immunity

BACKGROUND

Immune checkpoint blockade, such as monoclonal antibodies targeting programmed cell death protein 1 (PD-1), has been a major breakthrough in the treatment of several cancers, but has limited effect in colorectal cancer (CRC), which is a highly prevalent cancer worldwide. Current chemotherapy-based strategies to boost PD-1 response have many limitations. And the role of peripheral immunity in boosting PD-1 response continues to attract attention. Therefore, candidate combinations of PD-1 blockade need to be drugs with multi-targets and multi-modulatory functions. However, it is still unknown whether traditional Chinese medicines with such property can enhance the applicability and efficacy of PD-1 blockade in colorectal cancer.

METHODS

Euphorbia Pekinensis extract (EP) was prepared and the constituents were analyzed by HPLC. CRC cells were used for in vitro experiments, including cell viability assay, colony formation assay, flow cytometry for 7-AAD staining, western blotting for caspase 3 and caspase 7, HMGB1 and ATP detection. An orthotopic CT26 mouse model was subsequently used to investigate the combination of EP and PD-1 blockade therapy. Tumor volume and tumor weight were assessed, tumor tissues were subjected to histopathological HE staining and TUNEL staining, and tumor-infiltrating immune cells were evaluated by immunofluorescence staining. RNA-sequencing, target prediction and pathway analysis were further employed to explore the mechanism. Molecular docking and cellular thermal shift assay (CETSA) were utilized to verify the direct target of the core component of EP. And, loss-of-function analysis was carried to confirm the upstream-downstream relationship. Flow cytometry was employed to analyze CD8+ T cells in the peripheral blood and spleen.

RESULTS

The main constituents of EP are diterpenoids and flavonoids. EP dramatically suppresses CRC cell growth and exerts its cytotoxic effect by triggering immunogenic cell death in vitro. Moreover, EP synergizes with PD-1 blockade to inhibit tumorigenesis in tumor-bearing mice. Disruption of ISX nuclear localization by helioscopinolide E is a central mechanism of EP-induced apoptosis in CRC cell. Meanwhile, EP activates immune response by upregulating Phox2b to reshape the immune microenvironment. In addition, EP regulates peripheral immunity by regulating the T cell activation and proliferation, and the ratio of CD8+ T cells in peripheral blood is drastically increased, thereby enhancing the therapeutic efficacy of anti-PD1 immunotherapy.

CONCLUSION

EP triggers intra-tumor immunogenic cell death and modulates the immunoregulatory signaling to elicit the tumor immunogenicity. Moreover, EP participates in transcriptional activation of immune response-related pathways. Consequently, multiple stimulating functions of EP on macro- and micro-immune potentiates the anti-tumor effect of PD-1 blockade in CRC.

A surprising complete response to cadonilimab in a primary metastatic cervical cancer: a case report

The outcome of patients with recurrent/metastatic cervical cancer (R/M CC) is poor, with a 5-year survival rate of only 10%-20%. Recent advances in immunotherapy renewed its interest in R/M CC treatment. It has been suggested that cadonilimab, a novel bispecific antibody targeting programmed death 1 (PD-1) and cytotoxic T-lymphocyte antigen-4 (CTLA-4), significantly improved the survival outcomes of the R/M CC. In the present study, we reported a programmed death ligand 1 (PD-L1) and human epidermal growth factor receptor 2 (HER-2) positive CC case at stage IV who was treated with cadonilimab and achieved a surprising radiographic complete response (CR) for 10 months, even in the PD-L1 negative metastatic site. Demographic, clinical, histopathological, laboratory, treatment regime and imaging data were recorded. Unfortunately, the patient progressed rapidly during maintenance therapy when cadonilimab was replaced by sintilimab, the monoclonal antibody against PD-1, indicating the more powerful anti-tumor activity of dual blockade immunotherapy. To conclude, cadonilimab offers a promising and effective therapeutic approach for R/M CC. Notably, HER-2 is also expected to be a new reference target for cadonilimab therapy.

Potential predictive biomarkers in antitumor immunotherapy: navigating the future of antitumor treatment and immune checkpoint inhibitor efficacy

Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment modality, offering promising outcomes for various malignancies. However, the efficacy of ICIs varies among patients, highlighting the essential need of accurate predictive biomarkers. This review synthesizes the current understanding of biomarkers for ICI therapy, and discusses the clinical utility and limitations of these biomarkers in predicting treatment outcomes. It discusses three US Food and Drug Administration (FDA)-approved biomarkers, programmed cell death ligand 1 (PD-L1) expression, tumor mutational burden (TMB), and microsatellite instability (MSI), and explores other potential biomarkers, including tumor immune microenvironment (TIME)-related signatures, human leukocyte antigen (HLA) diversity, non-invasive biomarkers such as circulating tumor DNA (ctDNA), and combination biomarker strategies. The review also addresses multivariable predictive models integrating multiple features of patients, tumors, and TIME, which could be a promising approach to enhance predictive accuracy. The existing challenges are also pointed out, such as the tumor heterogeneity, the inconstant nature of TIME, nonuniformed thresholds and standardization approaches. The review concludes by emphasizing the importance of biomarker research in realizing the potential of personalized immunotherapy, with the goal of improving patient selection, treatment strategies, and overall outcomes in cancer treatment.

Resistance Management for Cancer: Lessons from Farmers

One of the main reasons we have not been able to cure cancers is that treatments select for drug-resistant cells. Pest managers face similar challenges with pesticides selecting for pesticide-resistant insects, resulting in similar mechanisms of resistance. Pest managers have developed 10 principles that could be translated to controlling cancers: (i) prevent onset, (ii) monitor continuously, (iii) identify thresholds below which there will be no intervention, (iv) change interventions in response to burden, (v) preferentially select nonchemical control methods, (vi) use target-specific drugs, (vii) use the lowest effective dose, (viii) reduce cross-resistance, (ix) evaluate success based on long-term management, and (x) forecast growth and response. These principles are general to all cancers and cancer drugs and so could be employed broadly to improve oncology. Here, we review the parallel difficulties in controlling drug resistance in pests and cancer cells. We show how the principles of resistance management in pests might be applied to cancer. Integrated pest management inspired the development of adaptive therapy in oncology to increase progression-free survival and quality of life in patients with cancers where cures are unlikely. These pest management principles have the potential to inform clinical trial design.

Therapeutic Landscape of FOXM1 in Triple-Negative Breast Cancer and Aggressive Solid Cancers

Triple-negative breast cancer (TNBC) is one of the most aggressive forms of breast cancer, lacking common treatment targets such as estrogen (ER), progesterone (PR), and HER2 receptors. This subtype is associated with significant heterogeneity, chemoresistance, early recurrence, metastasis, and poor patient survival. FOXM1 is a cancer-promoting transcription factor that plays a critical role in TNBC and other highly aggressive cancers by driving cell proliferation, invasion, metastasis, and drug resistance. In TNBC, mutations in the TP53 gene-detected in approximately 80% of patients-lead to the overexpression of FOXM1, making it a promising therapeutic target. Beyond TNBC, FOXM1 is implicated in other solid cancers, such as brain (glioblastoma), lung, and pancreatic cancers, and is considered an Achilles' heel of aggressive cancers. Despite its potential as a therapeutic target, there are currently no FDA-approved FOXM1 inhibitors, and none have advanced to clinical trials. This review explores the role of FOXM1 in cancer progression and highlights the current status of efforts to develop effective FOXM1 inhibitors.

Overcoming immunosuppression in cancer: how ketogenic diets boost immune checkpoint blockade

Immune checkpoint blockade (ICB) is now part of the standard of care in the treatment of many forms of cancer, yet it lacks efficacy in some patients, necessitating adjunct therapies to support the anti-tumor immune response. Ketogenic diets (KDs), i.e., high-fat low-carbohydrate diets, have been shown to have antiproliferative and immunomodulatory effects in various preclinical cancer studies. Here, we review current knowledge of the complex interplay of KDs and the anti-tumor immune response in the context of ICB therapy, to update our understanding of diet-induced immunometabolic reprogramming in cancer. Preclinical cancer studies have revealed increased activation of and infiltration by tumor-fighting immune cells, especially CD8+ T cells, but also M1 macrophages and natural killer cells, in response to a KD regimen. In contrast, immune-suppressive cells such as regulatory CD4+ T lymphocytes, M2 macrophages, and myeloid-derived suppressor cells were reported to be decreased or largely unaffected in tumors of KD-fed mice. KDs also showed synergism with ICB therapy in several preclinical tumor studies. The observed effects are ascribed to the ability of KDs to improve immune cell infiltration and induce downregulation of immune-inhibitory processes, thus creating a more immunogenic tumor microenvironment. The studies reviewed herein show that altering the metabolic composition of the tumor microenvironment by a KD can boost the anti-tumor immune response and diminish even immunotherapy-resistant as well as immunologically "cold" tumors. However, the exact underlying mechanisms remain to be elucidated, requiring further studies before KDs can be successfully implemented as an adjunct tumor therapy to improve survival rates for cancer patients.

Tumor microenvironment and cancer metastasis: molecular mechanisms and therapeutic implications

The tumor microenvironment (TME) plays a crucial role in cancer development and metastasis. This review summarizes the current research on how the TME promotes metastasis through molecular pathways, focusing on key components, such as cancer-associated fibroblasts, immune cells, endothelial cells, cytokines, and the extracellular matrix. Significant findings have highlighted that alterations in cellular communication within the TME enable tumor cells to evade immune surveillance, survive, and invade other tissues. This review highlights the roles of TGF-β and VEGF signaling in promoting angiogenesis and extracellular matrix remodeling, which facilitate metastasis. Additionally, we explored how metabolic reprogramming of tumor and stromal cells, influenced by nutrient availability in the TME, drives cancer progression. This study also evaluated the therapeutic strategies targeting these interactions to disrupt metastasis. By providing a multidisciplinary perspective, this study suggests that understanding the molecular basis of the TME can lead to more effective cancer therapies and identify potential avenues for future research. Future research on the TME should prioritize unraveling the molecular and cellular interactions within this complex environment, which could lead to novel therapeutic strategies and personalized cancer treatments. Moreover, advancements in technologies such as single-cell analysis, spatial transcriptomics, and epigenetic profiling offer promising avenues for identifying new therapeutic targets and improving the efficacy of immunotherapies, particularly in the context of metastasis.

Single-cell sequencing unveils mitophagy-related prognostic model for triple-negative breast cancer

Background

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer lacking hormone receptors and HER2 expression, leading to limited treatment options and poor prognosis. Mitophagy, a selective autophagy process targeting damaged mitochondria, plays a complex role in cancer progression, yet its prognostic significance in TNBC is not well understood.

Methods

This study utilized single-cell RNA sequencing data from the TCGA and GEO databases to identify mitophagy-related genes (MRGs) associated with TNBC. A prognostic model was developed using univariate Cox analysis and LASSO regression. The model was validated across multiple independent cohorts, and correlations between MRG expression, immune infiltration, and drug sensitivity were explored.

Results

Nine key MRGs were identified and used to stratify TNBC patients into high-risk and low-risk groups, with the high-risk group showing significantly worse survival outcomes. The model demonstrated strong predictive accuracy across various datasets. Additionally, the study revealed a correlation between higher MRG expression levels and increased immune cell infiltration, as well as potential responsiveness to specific chemotherapeutic agents.

Conclusion

The mitophagy-related prognostic model offers a novel method for predicting outcomes in TNBC patients and highlights the role of mitophagy in influencing the tumor microenvironment, with potential applications in personalized treatment strategies.

Blockade of CCR5+ T Cell Accumulation in the Tumor Microenvironment Optimizes Anti-TGF-β/PD-L1 Bispecific Antibody

In the previous studies, anti-TGF-β/PD-L1 bispecific antibody YM101 is demonstrated, with superior efficacy to anti-PD-L1 monotherapy in multiple tumor models. However, YM101 therapy can not achieve complete regression in most tumor-bearing mice, suggesting the presence of other immunosuppressive elements in the tumor microenvironment (TME) beyond TGF-β and PD-L1. Thoroughly exploring the TME is imperative to pave the way for the successful translation of anti-TGF-β/PD-L1 BsAb into clinical practice. In this work, scRNA-seq is employed to comprehensively profile the TME changes induced by YM101. The scRNA-seq analysis reveals an increase in immune cell populations associated with antitumor immunity and enhances cell-killing pathways. However, the analysis also uncovers the presence of immunosuppressive CCR5+ T cells in the TME after YM101 treatment. To overcome this hurdle, YM101 is combined with Maraviroc, a widely used CCR5 antagonist for treating HIV infection, suppressing CCR5+ T cell accumulation, and optimizing the immune response. Mechanistically, YM101-induced neutrophil activation recruits immunosuppressive CCR5+ T cells via CCR5 ligand secretion, creating a feedback loop that diminishes the antitumor response. Maraviroc then cleared these infiltrating cells and offset YM101-mediated immunosuppressive effects, further unleashing the antitumor immunity. These findings suggest selectively targeting CCR5 signaling with Maraviroc represents a promising and strategic approach to enhance YM101 efficacy.

Discovery of Benzo[d]oxazoles as Novel Dual Small-Molecule Inhibitors Targeting PD-1/PD-L1 and VISTA Pathway

The blockers of programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) pathway have achieved great clinical success. However, the limited efficacy and low tumor response rate of anti-PD-1/PD-L1 monotherapy limit the clinical application of PD-1/PD-L1 inhibitors. V-domain immunoglobulin suppressor of T-cell activation (VISTA), a novel checkpoint regulator, exhibits potential synergy with PD-1/PD-L1 in enhancing antitumor immunity. Herein, we report the discovery of benzo[d]oxazole B3 as novel dual small-molecule inhibitors targeting PD-1/PD-L1 and VISTA with high PD-1/PD-L1 inhibitory activity and VISTA binding affinity. B3 rescues the immunosuppression of T-cells mediated by PD-L1 and VISTA and activates antitumor immunity effectively. Moreover, B3 could induce degradation of PD-L1 and VISTA in tumor cell. Furthermore, B3 displays significant in vivo antitumor efficacy in a CT26 mouse model. Our results discover B3 as a promising dual PD-1/PD-L1 and VISTA inhibitor, providing a novel therapeutic strategy to overcome the limitations of current anti-PD-1/PD-L1 therapy.

Gastrointestinal adverse events associated with immune checkpoint inhibitors: a pharmacovigilance analysis of the EudraVigilance and VigiAccess databases

BACKGROUND

This study aimed to provide an overview of gastrointestinal (GI) adverse events associated with immune checkpoint inhibitors (ICIs) using two pharmacovigilance databases, EudraVigilance and VigiAccess.

RESEARCH DESIGN AND METHODS

Data was collected from the date of ICI's marketing authorization until 30 November 2023. Reporting odds ratio (ROR) was used as a measure of ADR reporting disproportionality for signal detection.

RESULTS

Overall, across both databases, EudraVigilance and VigiAccess, a total of 76,606 ADR reports were analyzed. In EudraVigilance, colitis (12,581) and diarrhea (12,108) were the most reported GI adverse events, with similar findings in VigiAccess. Furthermore, in both databases, the most ADR reports were associated with nivolumab and pembrolizumab. Durvalumab (ROR:3.96,95%CI:3.65-4.28), ipilimumab (ROR:1.95,95%CI:1.89-2.01), nivolumab (ROR:1.05,95%CI:1.02-1.07), and atezolizumab (ROR:1.04,95%CI:1.01-1.07) demonstrated higher risks of GI events compared to other ICIs. EudraVigilance analysis identified dysphagia, ascites, hematochezia, and gastroesophageal reflux disease as potential signals associated with ICI therapy. Majority of ADR reports (87.2%) comprised serious GI adverse events, a portion of which was associated with fatal outcomes (14.5%). Atezolizumab (14.9%) and pembrolizumab (11.9%) were linked to a higher incidence of fatal outcomes compared to other ICIs.

CONCLUSION

The differential risk profiles of ICIs-associated-GI adverse events underscore the importance of personalized therapy in oncology.

Small-Molecule Radiotracers for Visualization of V-Domain Immunoglobulin Suppressor of T Cell Activation

V-domain immunoglobulin suppressor of T cell activation (VISTA) plays a critical role in regulating innate and adaptive immune responses within the tumor immune microenvironment. Quantifying VISTA expression is necessary to determine whether patients respond to a related combination immunotherapy. This study developed two 68Ga-labeled small-molecule probes ([68Ga]Ga-DCA and [68Ga]Ga-DNCA) for visualizing and differentiating VISTA expression. These probes exhibited excellent targeting capabilities for multiple tumor types (including B16-F10, 4T1, MC38, and CT26 tumors), consistent with the levels of VISTA expression determined by immunoblotting. Co-injection of inhibitor CA-170 led to decreased tumor uptake of both [68Ga]Ga-DCA and [68Ga]Ga-DNCA. [68Ga]Ga-DCA was used to verify the feasibility of monitoring VISTA expression in lung metastasis models. In summary, this study describes the use of 68Ga-labeled CA-170 analogues as small-molecule probes for imaging VISTA. This could provide a visual method and enable personalized immunotherapy in patients.

The Mutual Regulatory Role of Ferroptosis and Immunotherapy in Anti-tumor Therapy

Ferroptosis is a form of cell death that is triggered by the presence of ferrous ions and is characterized by lipid peroxidation induced by these ions. The mechanism exhibits distinct morphological characteristics compared to apoptosis, autophagy, and necrosis. A notable aspect of ferroptosis is its ability to inhibit uncontrolled tumor replication and immortalization, especially in malignant, drug-resistant, and metastatic tumors. Additionally, immunotherapy, a novel therapeutic approach for tumors, has been found to have a reciprocal regulatory relationship with ferroptosis in the context of anti-tumor therapy. A comprehensive analysis of ferroptosis and immunotherapy in tumor therapy is presented in this paper, highlighting the potential for mutual adjuvant effects. Specifically, we discuss the mechanisms underlying ferroptosis and immunotherapy, emphasizing their ability to improve the tumor immune microenvironment and enhance immunotherapeutic effects. Furthermore, we investigate how immunotherapeutic factors may increase the sensitivity of tumor cells to ferroptosis. We aim to provide a prospective view of the promising value of combined ferroptosis and immunotherapy in anticancer therapy by elucidating the mutual regulatory network between each.

Prognostic biomarkers for immunotherapy in esophageal cancer

Esophageal cancer (EC), a common type of malignant tumor, ranks as the sixth highest contributor to cancer-related mortality worldwide. Due to the condition that most patients with EC are diagnosed at advanced or metastatic status, the efficacy of conventional treatments including surgery, chemotherapy and radiotherapy is limited, resulting in a dismal 5-year overall survival rate. In recent years, the application of immune checkpoint inhibitors (ICIs) has presented a novel therapeutic avenue for EC patients. Both ICIs monotherapy and immunotherapy combined with chemotherapy or chemoradiotherapy (CRT) have demonstrated marked benefits for patients with advanced EC. Adjuvant or neoadjuvant therapy incorporating immunotherapy has also demonstrated promising prospects in the context of perioperative treatment. Nonetheless, due to the variable response observed among patients undergoing immunotherapy, it is of vital importance to identify predictive biomarkers for patient stratification, to facilitate identification of subgroups who may derive greater benefits from immunotherapy. In this review, we summarize validated or potential biomarkers for immunotherapy in EC in three dimensions: tumor-cell-associated biomarkers, tumor-immune microenvironment (TIME)-associated factors, and host-associated biomarkers, so as to provide a theoretical foundation to inform tailored therapy for individuals diagnosed with EC.

Unveiling promising targets in gastric cancer therapy: A comprehensive review

Gastric cancer (GC) poses a significant global health challenge, ranking fifth in incidence and third in mortality among all malignancies worldwide. Its insidious onset, aggressive growth, proclivity for metastasis, and limited treatment options have contributed to its high fatality rate. Traditional approaches for GC treatment primarily involve surgery and chemotherapy. However, there is growing interest in targeted therapies and immunotherapies. This comprehensive review highlights recent advancements in GC targeted therapy and immunotherapy. It delves into the mechanisms of various strategies, underscoring their potential in GC treatment. Additionally, the review evaluates the efficacy and safety of relevant clinical trials. Despite the benefits observed in numerous advanced GC patients with targeted therapies and immunotherapies, challenges persist. We discuss pertinent strategies to overcome these challenges, thereby providing a solid foundation for enhancing the clinical effectiveness of targeted therapies and immunotherapies.

CDK6 as a Biomarker for Immunotherapy, Drug Sensitivity, and Prognosis in Bladder Cancer: Bioinformatics and Immunohistochemical Analysis

Background: CDK6 is linked to tumor progression and metastasis, although its molecular mechanism and prognostic value are unclear in bladder cancer. Materials and methods: In our study, raw data were obtained from public databases and Single-center retrospective case series. We conducted a bioinformatics analysis and immunohistochemistry to explore the biological landscape of CDK6 in tumors, with a particular focus on bladder cancer. We examined its expression characteristics and prognostic value and performed functional annotation analysis using gene function enrichment. We also assessed the association between bladder cancer molecular subtypes and mutation spectra and analyzed the landscape of the tumor immune microenvironment to predict treatment response sensitivity. Results: Our study found that CDK6 was a potential prognostic marker for bladder cancer. We discovered that bladder cancer patients with high CDK6 expression do not respond well to immunotherapy and have a poor prognosis. CDK6 regulates tumor immune status, metabolism, and cell cycle-related signaling pathways, thereby influencing tumor biological behavior. Furthermore, CDK6 mediated the suppression of the immune microenvironment to weaken anti-tumor immune responses. Finally, a comprehensive characterization of CDK6 was applied in the prognostic prediction of bladder cancer, suggesting that targeting CDK6 represents a potential therapeutic option. Conclusions: These results indicated that CDK6 is an independent biomarker for predicting prognosis and immunotherapy efficacy of bladder cancer. A deeper understanding of its specific molecular mechanisms may provide new treatment strategies.

Comprehensive Glycomic and Glycoproteomic Analyses of Human Programmed Cell Death Protein 1 Extracellular Domain

Human programmed cell death protein 1 (hPD-1) is an essential receptor in the immune checkpoint pathway. It has played an important role in cancer therapy. However, not all patients respond positively to the PD-1 antibody treatment, and the underlying mechanism remains unknown. PD-1 is a transmembrane glycoprotein, and its extracellular domain (ECD) is reported to be responsible for interactions and signal transduction. This domain contains 4 N-glycosylation sites and 25 potential O-glycosylation sites, which implicates the importance of glycosylation. The structure of hPD-1 has been intensively studied, but the glycosylation of this protein, especially the glycan on each glycosylation site, has not been comprehensively illustrated. In this study, hPD-1 ECD expressed by human embryonic kidney 293 (HEK 293) and Chinese hamster ovary (CHO) cells was analyzed; not only N- and O-glycosylation sites but also the glycans on these sites were comprehensively analyzed using mass spectrometry. In addition, hPD-1 ECD binding to different anti-hPD-1 antibodies was tested, and N-glycans were found functioned differently. All of this glycan information will be beneficial for future PD-1 studies.

Biological functions and potential mechanisms of miR‑143‑3p in cancers (Review)

In recent years, microRNAs (miRNAs or miRs) have been increasingly studied for their role in cancer and have shown potential as cancer biomarkers. miR‑143‑3p and miR‑143‑5p are the mature miRNAs derived from pre‑miRNA‑143. At present, there are numerous studies on the function of miR‑143‑3p in cancer progression, but there are no systematic reviews describing the function of miR‑143‑3p in cancer. It is widely considered that miR‑143‑3p is downregulated in most malignant tumors and that upstream regulators can act on this gene, which in turn regulates the corresponding target to act on the tumor. In addition, miRNA‑143‑3p can regulate target genes to affect the biological process of tumors through various signaling pathways, such as the PI3K/Akt, Wnt/β‑catenin, AKT/STAT3 and Ras‑Raf‑MEK‑ERK pathways. The present review comprehensively described the biogenesis of miR‑143‑3p, the biological functions of miR‑143‑3p and the related roles and mechanisms in different cancer types. The potential of miR‑143‑3p as a biomarker for cancer was also highlighted and valuable future research directions were discussed.

Immune checkpoint reprogramming via sequential nucleic acid delivery strategy optimizes systemic immune responses for gastrointestinal cancer immunotherapy

Monoclonal antibodies targeting immune checkpoints have been widely applied in gastrointestinal cancer immunotherapy. However, systemic administration of various monoclonal antibodies does not often result in sustained effects in reversing the immunosuppressive tumor microenvironment (TME), which may be due to the spatiotemporal dynamic changes of immune checkpoints. Herein, we reported a novel immune checkpoint reprogramming strategy for gastrointestinal cancer immunotherapy. It was achieved by the sequential delivery of siPD-L1 (siRNA for programmed cell death ligand 1) and pOX40L (plasmid for OX40 ligand), which were complexed with two cationic polymer brush-grafted carbon nanotubes (dense short (DS) and dense long (DL)) designed based on the structural characteristics of nucleic acids and brush architectures. Upon administrating DL/pOX40L for the first three dosages, then followed by DS/siPD-L1 for the next three dosages to the TME, it upregulated the stimulatory checkpoint OX40L on dendritic cells (DCs) and downregulated inhibitory checkpoint PD-L1 on tumor cells and DCs in a sequential reprogramming manner. Compared with other combination treatments, this sequential strategy drastically boosted the DCs maturation, and CD8+ cytotoxic T lymphocytes infiltration in tumor site. Furthermore, it could augment the local antitumor response and improve the T cell infiltration in tumor-draining lymph nodes to reverse the peripheral immunosuppression. Our study demonstrated that sequential nucleic acid delivery strategy via personalized nanoplatforms effectively reversed the immunosuppression status in both tumor microenvironment and peripheral immune landscape, which significantly enhanced the systemic antitumor immune responses and established an optimal immunotherapy strategy against gastrointestinal cancer.

Immunosuppressive tumor microenvironment in the progression, metastasis, and therapy of hepatocellular carcinoma: from bench to bedside

Hepatocellular carcinoma (HCC) is a highly heterogeneous malignancy with high incidence, recurrence, and metastasis rates. The emergence of immunotherapy has improved the treatment of advanced HCC, but problems such as drug resistance and immune-related adverse events still exist in clinical practice. The immunosuppressive tumor microenvironment (TME) of HCC restricts the efficacy of immunotherapy and is essential for HCC progression and metastasis. Therefore, it is necessary to elucidate the mechanisms behind immunosuppressive TME to develop and apply immunotherapy. This review systematically summarizes the pathogenesis of HCC, the formation of the highly heterogeneous TME, and the mechanisms by which the immunosuppressive TME accelerates HCC progression and metastasis. We also review the status of HCC immunotherapy and further discuss the existing challenges and potential therapeutic strategies targeting immunosuppressive TME. We hope to inspire optimizing and innovating immunotherapeutic strategies by comprehensively understanding the structure and function of immunosuppressive TME in HCC.

The immune regulatory function of B7-H3 in malignancy: spotlight on the IFN-STAT1 axis and regulation of tumor-associated macrophages

B7-H3 is a member of the B7 superfamily and a putative inhibitory immune checkpoint molecule. Several early-phase clinical trials have reported promising anti-tumor activity and safety of anti-cancer drugs targeting B7-H3, suggesting that it may be a promising target for a potential next-generation immune checkpoint inhibitor. Despite ongoing clinical studies, most B7-H3-targeted drugs being currently investigated rely on direct cytotoxicity as their mechanisms of action rather than modulating its function as an immune checkpoint, at least in part due to its incompletely understood immune regulatory function. Recent studies have begun to elucidate the role of B7-H3 in regulating the tumor microenvironment (TME). Emerging evidence suggests that B7-H3 may regulate the interferon-STAT1 axis in the TME and promote immune suppression. Similarly, increasing evidence shows B7-H3 may be implicated in promoting M1 to M2 polarization of tumor-associated macrophages (TAMs). There is also accumulating evidence suggesting that B7-H3 may play a role in the heterotypic fusion of cancer stem cells and macrophages, thereby promoting tumor invasion and metastasis. Here, we review the recent advances in the understanding of B7-H3 cancer immunobiology with a focus on highlighting its potential role in the interferon priming of TAMs and the heterotypic fusion of TAMs with cancer stem cells and suggest future direction in elucidating its immune checkpoint function.

Targeting novel regulated cell death: Ferroptosis, pyroptosis and necroptosis in anti-PD-1/PD-L1 cancer immunotherapy

Chemotherapy, radiotherapy, and immunotherapy represent key tumour treatment strategies. Notably, immune checkpoint inhibitors (ICIs), particularly anti-programmed cell death 1 (PD1) and anti-programmed cell death ligand 1 (PD-L1), have shown clinical efficacy in clinical tumour immunotherapy. However, the limited effectiveness of ICIs is evident due to many cancers exhibiting poor responses to this treatment. An emerging avenue involves triggering non-apoptotic regulated cell death (RCD), a significant mechanism driving cancer cell death in diverse cancer treatments. Recent research demonstrates that combining RCD inducers with ICIs significantly enhances their antitumor efficacy across various cancer types. The use of anti-PD-1/PD-L1 immunotherapy activates CD8+ T cells, prompting the initiation of novel RCD forms, such as ferroptosis, pyroptosis, and necroptosis. However, the functions and mechanisms of non-apoptotic RCD in anti-PD1/PD-L1 therapy remain insufficiently explored. This review summarises the emerging roles of ferroptosis, pyroptosis, and necroptosis in anti-PD1/PD-L1 immunotherapy. It emphasises the synergy between nanomaterials and PD-1/PD-L1 inhibitors to induce non-apoptotic RCD in different cancer types. Furthermore, targeting cell death signalling pathways in combination with anti-PD1/PD-L1 therapies holds promise as a prospective immunotherapy strategy for tumour treatment.

Peptide-stimulated T cells bypass immune checkpoint inhibitor resistance and eliminate autologous microsatellite instable colorectal cancer cells

Two hypermutated colon cancer cases with patient-derived cell lines, peripheral and tumor-infiltrating T cells available were selected for detailed investigation of immunological response.T cells co-cultured with autologous tumor cells showed only low levels of pro-inflammatory cytokines and failed at tumor recognition. Similarly, treatment of co-cultures with immune checkpoint inhibitors (ICI) did not boost antitumor immune responses. Since proteinase inhibitor 9 (PI-9) was detected in tumor cells, a specific inhibitor (PI-9i) was used in addition to ICI in T cell cytotoxicity testing. However, only pre-stimulation with tumor-specific peptides (cryptic and neoantigenic) significantly increased recognition and elimination of tumor cells by T cells independently of ICI or PI-9i.We showed, that ICI resistant tumor cells can be targeted by tumor-primed T cells and also demonstrated the superiority of tumor-naïve peripheral blood T cells compared to highly exhausted tumor-infiltrating T cells. Future precision immunotherapeutic approaches should include multimodal strategies to successfully induce durable anti-tumor immune responses.