Immune checkpoint signaling and cancer immunotherapy

Immunotherapy resistance in solid tumors: mechanisms and potential solutions

While the emergence of immunotherapies has fundamentally altered the management of solid tumors, cancers exploit many complex biological mechanisms that result in resistance to these agents. These encompass a broad range of cellular activities - from modification of traditional paradigms of immunity via antigen presentation and immunoregulation to metabolic modifications and manipulation of the tumor microenvironment. Intervening on these intricate processes may provide clinical benefit in patients with solid tumors by overcoming resistance to immunotherapies, which is why it has become an area of tremendous research interest with practice-changing implications. This review details the major ways cancers avoid both natural immunity and immunotherapies through primary (innate) and secondary (acquired) mechanisms of resistance, and it considers available and emerging therapeutic approaches to overcoming immunotherapy resistance.

Identification of novel PD-1/PD-L1 small molecule inhibitors: virtual screening, synthesis and in vitro characterisation

The PD-1/PD-L1 pathway is considered as one of the most promising immune checkpoints in tumour immunotherapy. However, researchers are faced with the inherent limitations of antibodies, driving them to pursue PD-L1 small molecule inhibitors. Virtual screening followed by experimental validation is a proven approach to discover active compounds. In this study, we employed multistage virtual screening methods to screen multiple compound databases to predict new PD-1/PD-L1 ligands. 35 compounds were proposed by combined analysis of fitness scores, interaction pattern and MM-GBSA binding affinities. Enzymatic assay confirmed that 10 out of 35 ligands were potential PD-L1 inhibitors, with inhibitory rate higher than 50% at the concentration of 30 µM. Among them, ZDS20 was identified as the most effective inhibitor with low micromolar activity (IC50 = 3.27 μM). Altogether, ZDS20 carrying novel scaffold was identified and could serve as a lead for the development of new classes of PD-L1 inhibitors.

Emerging trends and therapeutic applications of monoclonal antibodies

Monoclonal antibodies (mAbs) are being used to prevent, detect, and treat a broad spectrum of malignancies and infectious and autoimmune diseases. Over the past few years, the market for mAbs has grown exponentially. They have become a significant part of many pharmaceutical product lines, and more than 250 therapeutic mAbs are undergoing clinical trials. Ever since the advent of hybridoma technology, antibody-based therapeutics were realized using murine antibodies which further progressed into humanized and fully human antibodies, reducing the risk of immunogenicity. Some of the benefits of using mAbs over conventional drugs include a drastic reduction in the chances of adverse reactions, interactions between drugs, and targeting specific proteins. While antibodies are very efficient, their higher production costs impede the process of commercialization. However, their cost factor has been improved by developing biosimilar antibodies, which are affordable versions of therapeutic antibodies. Along with biosimilars, innovations in antibody engineering have helped to design bio-better antibodies with improved efficacy than the conventional ones. These novel mAb-based therapeutics are set to revolutionize existing drug therapies targeting a wide spectrum of diseases, thereby meeting several unmet medical needs. In the future, mAbs generated by applying next-generation sequencing (NGS) are expected to become a powerful tool in clinical therapeutics. This article describes the methods of mAb production, pre-clinical and clinical development of mAbs, approved indications targeted by mAbs, and novel developments in the field of mAb research.

Immune-checkpoint gene expression and BCG response in non-muscle invasive bladder cancer

METHODS

One-hundred-six patients diagnosed with non-muscle invasive bladder cancer and treated with intravesical BCG were included and divided into two groups, BCG-responsive (n = 47) and -unresponsive (n = 59). Immunohistochemistry was used to evaluate PD-L1 expression and MSI was assessed by a commercial multiplex PCR kit. The mRNA expression profile of 15 immune checkpoints was performed using the nCounter technology. For in silico validation, two distinct cohorts sourced from the Gene Expression Omnibus (GEO) database were used.

RESULTS

Among the 106 patients, only one (<1 %) exhibited MSI instability. PD-L1 expression was present in 9.4 % of cases, and no association was found with BCG-responsive status. We found low gene expression of canonic actionable immune checkpoints PDCD1 (PD-1), CD274 (PD-L1), and CTLA4, while high expression was observed for CD276 (B7-H3), CD47, TNFRSF14, IDO1 and PVR (CD155) genes. High IDO1 expression levels was associated with worst overall survival. The PDCD1, CTLA4 and TNFRSF14 expression levels were associated with BCG responsiveness, whereas TIGIT and CD276 were associated with unresponsiveness. Finally, CD276 was validated in silico cohorts.

CONCLUSION

In NMIBC, MSI is rare and PD-L1 expression is present in a small subset of cases. Expression levels of PDCD1, CTLA4, TNFRSF14, TIGIT and CD276 could constitute predictive biomarkers of BCG responsiveness.

Synthesis and Characterization of a Novel PET Tracer for Noninvasive Evaluation of FGL1 Status in Tumors

Fibrinogen-like protein 1 (FGL1) is a potential novel immune checkpoint target for malignant tumor diagnosis and therapy. Accurate detection of FGL1 levels in tumors via noninvasive PET imaging might be beneficial for managing the disease. To achieve this, multiple FGL1-targeting peptides (FGLP) were designed, and a promising candidate, 68Ga-NOTA-FGLP2, was identified through a high-throughput screening approach using microPET imaging of 68Ga-labeled peptides. Subsequent in vitro cell experiments showed that uptake values of 68Ga-NOTA-FGLP2 in FGL1 positive Huh7 tumor cells were significantly higher than those in FGL1 negative U87 MG tumor cells. Further microPET imaging showed that the Huh7 xenografts were clearly visualized with a favorable contrast. ROI analysis showed that the uptake values of the tracer in Huh7 xenografts were 2.63 ± 0.07% ID/g at 30 min p.i.. After treatment with an excess of unlabeled FGLP2, the tumor uptake significantly decreased to 0.54 ± 0.05% ID/g at 30 min p.i.. Moreover, the uptake in U87 MG xenografts was 0.44 ± 0.06% ID/g at the same time point. The tracer was excreted mainly through the renal system. 18F-FDG PET imaging was also performed in mice bearing Huh7 and U87 MG xenografts, respectively. However, there was no significant difference in the uptake between the tumors with different FGL1 expressions. Preclinical data indicated that 68Ga-NOTA-FGLP2 might be a suitable radiotracer for in vivo noninvasive visualization of tumors with abundant expression of FGL1. Further investigation of 68Ga-NOTA-FGLP2 for tumor diagnosis and therapy is undergoing.

Soluble form of immune checkpoints in autoimmune diseases

Immune checkpoints are essential regulators of immune responses, either by activating or suppressing them. Consequently, they are regarded as pivotal elements in the management of infections, cancer, and autoimmune disorders. In recent years, researchers have identified numerous soluble immune checkpoints that are produced through various mechanisms and demonstrated biological activity. These soluble immune checkpoints can be produced and distributed in the bloodstream and various tissues, with their roles in immune response dysregulation and autoimmunity extensively documented. This review aims to provide a thorough overview of the generation of various soluble immune checkpoints, such as sPD-1, sCTLA-4, sTim-3, s4-1BB, sBTLA, sLAG-3, sCD200, and the B7 family, and their importance as indicators for the diagnosis and prediction of autoimmune conditions. Furthermore, the review will investigate the potential pathological mechanisms of soluble immune checkpoints in autoimmune diseases, emphasizing their association with autoimmune diseases development, prognosis, and treatment.

Construction of [89Zr]Zr-Labeled HuL13 for ImmunoPET Imaging of LAG-3 Checkpoint Expression on Tumor-Infiltrating T Cells

Lymphocyte activation gene 3 (LAG-3) has attracted much attention as a potentially valuable immune checkpoint. Individual identification of LAG-3 expression at screening and during treatment could improve the successful implementation of anti-LAG-3 therapies. HuL13 is a human IgG1 monoclonal antibody that binds to the LAG-3 receptor in T cells. Here, we used [89Zr]Zr-labeled HuL13 to delineate LAG-3+ T-cell infiltration into tumors via positron emission tomography (PET) imaging. A549/LAG-3 cells, which stably express LAG-3, were generated by infection with lentivirus. The uptake of [89Zr]Zr-DFO-HuL13 in A549/LAG-3 cells was greater than that in the negative control (A549/NC) cells at each time point. The equilibrium dissociation constant (Kd) of [89Zr]Zr-DFO-HuL13 for the LAG-3 receptor was 8.22 nM. PET imaging revealed significant uptake in the tumor areas of A549/LAG-3 tumor-bearing mice from 24 h after injection (SUVmax = 2.43 ± 0.06 at 24 h). As a proof of concept, PET imaging of the [89Zr]Zr-DFO-HuL13 tracer was further investigated in an MC38 tumor-bearing humanized LAG-3 mouse model. PET imaging revealed that the [89Zr]Zr-DFO-HuL13 tracer specifically targets human LAG-3 expressed on tumor-infiltrating lymphocytes (TILs). In addition to the tumors, the spleen was also noticeably visible. Tumor uptake of the [89Zr]Zr-DFO-HuL13 tracer was lower than its uptake in the spleen, but high uptake in the spleen could be reduced by coinjection of unlabeled antibodies. Coinjection of unlabeled antibodies increases tracer activity in the blood pool, thereby improving tumor uptake. Dosimetry evaluation of the healthy mouse models revealed that the highest absorbed radiation dose was in the spleen, followed by the liver and heart wall. In summary, these studies demonstrate the feasibility of using the [89Zr]Zr-DFO-HuL13 tracer for the detection of LAG-3 expression on TILs. Further clinical evaluation of the [89Zr]Zr-DFO-HuL13 tracer may be of significant help in the stratification and management of patients suitable for anti-LAG-3 therapy.

Design, Synthesis, and Biological Evaluation of Chroman Derivatives as PD-1/PD-L1 Antagonists

Programmed death-ligand 1 (PD-L1) has emerged as a promising therapeutic target for various cancers due to its crucial role in promoting tumor immune evasion. Here, we report a novel class of chroman-like small-molecule PD-L1 inhibitors exhibiting significant activity in inhibiting the PD-1/PD-L1 interaction. Employing a "ring-close" strategy for conformational restriction, we have achieved compound C27, which demonstrates superior PD-1/PD-L1 inhibitory activity compared to the positive control. Molecular dynamics simulation and binding free energy calculation predict that (R)-C27 with inhibitory activity surpassed (S)-C27. The experimental results from bioassay and X-ray structural analysis corroborate these findings. All these results collectively indicate that (R)-C27 is a promising lead compound deserving further exploration.

Cancer cell plasticity defines response to immunotherapy in cutaneous squamous cell carcinoma

Immune checkpoint blockade (ICB) approaches have changed the therapeutic landscape for many tumor types. However, half of cutaneous squamous cell carcinoma (cSCC) patients remain unresponsive or develop resistance. Here, we show that, during cSCC progression in male mice, cancer cells acquire epithelial/mesenchymal plasticity and change their immune checkpoint (IC) ligand profile according to their features, dictating the IC pathways involved in immune evasion. Epithelial cancer cells, through the PD-1/PD-L1 pathway, and mesenchymal cancer cells, through the CTLA-4/CD80 and TIGIT/CD155 pathways, differentially block antitumor immune responses and determine the response to ICB therapies. Accordingly, the anti-PD-L1/TIGIT combination is the most effective strategy for blocking the growth of cSCCs that contain both epithelial and mesenchymal cancer cells. The expression of E-cadherin/Vimentin/CD80/CD155 proteins in cSCC, HNSCC and melanoma patient samples predicts response to anti-PD-1/PD-L1 therapy. Collectively, our findings indicate that the selection of ICB therapies should take into account the epithelial/mesenchymal features of cancer cells.

Hypomethylation-enhanced CRTC2 expression drives malignant phenotypes and primary resistance to immunotherapy in hepatocellular carcinoma

The cyclic AMP-responsive element-binding protein (CREB)-regulated transcription coactivator 2 (CRTC2) is a crucial regulator of hepatic lipid metabolism and gluconeogenesis and correlates with tumorigenesis. However, the mechanism through which CRTC2 regulates hepatocellular carcinoma (HCC) progression is largely unknown. Here, we found that increased CRTC2 expression predicted advanced tumor grade and stage, as well as worse prognosis in patients with HCC. DNA promoter hypomethylation led to higher CRTC2 expression in HCC. Functionally, CRTC2 contributed to HCC malignant phenotypes through the activated Wnt/β-catenin pathway, which could be abrogated by the small-molecular inhibitor XAV-939. Moreover, Crtc2 facilitated tumor growth while concurrently downregulating the PD-L1/PD-1 axis, resulting in primary resistance to immunotherapy. In immunocompetent mice models of HCC, targeting Crtc2 in combination with anti-PD-1 therapy prominently suppressed tumor growth by synergistically enhancing responsiveness to immunotherapy. Collectively, targeting CRTC2 might be a promising therapeutic strategy to sensitize immunotherapy in HCC.

Enhancing antitumor efficacy of oncolytic virus M1 via albendazole-sustained CD8+ T cell activation

The immune response plays a crucial role in the functionality of oncolytic viruses. In this study, Albendazole, an antihelminthic drug known to modulate the immune checkpoint PD-L1, was combined with the oncolytic virus M1 (OVM1) to treat mice with either prostate cancer (RM-1) or glioma (GL261) tumors. This combination therapy enhanced anti-tumor effects in immunocompetent mice, but not in immunodeficient ones, without increasing OVM1 replication. Instead, it led to an increase in the number of CD8+ T cells within the tumor, downregulated the expression of PD1 on CD8+ T cells, and upregulated activation markers such as Ki67, CD44, and CD69 and the secretion of cytotoxic factors including interferon (IFN)-γ, granzyme B, and tumor necrosis factor (TNF)-α. Consistently, it enhanced the in vitro tumor-killing activity of lymphocytes from tumor-draining lymph nodes or spleens. The synergistic effect of Albendazole on OVM1 was abolished by depleting CD8+ T cells, suggesting a CD8+ T cell-dependent mechanism. In addition, Albendazole and OVM1 therapy increased CTLA4 expression in the spleen, and the addition of CTLA4 antibodies further enhanced the anti-tumor efficacy in vivo. In summary, Albendazole can act synergistically with oncolytic viruses via CD8+ T cell activation, and the Albendazole/OVM1 combination can overcome resistance to CTLA4-based immune checkpoint blockade therapy.

Dissolving microneedles for transdermal drug delivery in cancer immunotherapy

Immunotherapy is an important approach in cancer treatment. Transdermal administration is emerging as a promising method for delivering immunotherapeutics. Dissolving microneedles are made mainly of soluble or biodegradable polymers and have garnered widespread attention due to their painlessness, safety, convenience, excellent drug loading capacity, and easy availability of various materials, making them an ideal transdermal delivery system. This review comprehensively summarized the preparation methods, materials, and applications of dissolving microneedles in cancer vaccines, immune checkpoint inhibitors, and adoptive cell therapy. Additionally, the challenges and perspectives associated with their future clinical translation are discussed.

Discovery of Novel Proteolysis-Targeting Chimera Molecules as Degraders of Programmed Cell Death-Ligand 1 for Breast Cancer Therapy

The immune checkpoint blockade represents a pivotal strategy for tumor immunotherapy. At present, various programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) monoclonal antibodies have been successfully applied to tumor treatment. Additionally, numerous small molecule inhibitors of the PD-1/PD-L1 interaction have also been developed, with some advancing into clinical trials. Here, a novel PD-L1 proteolysis-targeting chimera (PROTAC) library was designed and synthesized utilizing the PD-L1 inhibitor BMS202 and the E3 ligand PG as foundational components. Among these, we identified a highly potent molecule PA8 for PD-L1 degradation in 4T1 cells (DC50 = 0.609 μM). Significantly, compound PA8 potentially inhibits 4T1 cell growth both in vitro and in vivo. Further mechanistic studies revealed that PA8 effectively promoted the immune activation of model mice. Thus, these results suggest that PA8 could be a novel strategy for cancer immunotherapy in the 4T1 tumor model. Although PA8 exhibits weaker degradation activity in some human cancer cells, it still provides a certain basis for further research on PD-L1 PROTAC.

The role of transforming growth factor-β (TGF-β) in the formation of exhausted CD8 + T cells

CD8 + T cells exert a critical role in eliminating cancers and chronic infections, and can provide long-term protective immunity. However, under the exposure of persistent antigen, CD8 + T cells can differentiate into terminally exhausted CD8 + T cells and lose the ability of immune surveillance and disease clearance. New insights into the molecular mechanisms of T-cell exhaustion suggest that it is a potential way to improve the efficacy of immunotherapy by restoring the function of exhausted CD8 + T cells. Transforming growth factor-β (TGF-β) is an important executor of immune homeostasis and tolerance, inhibiting the expansion and function of many components of the immune system. Recent studies have shown that TGF-β is one of the drivers for the development of exhausted CD8 + T cells. In this review, we summarized the role and mechanisms of TGF-β in the formation of exhausted CD8 + T cells and discussed ways to target those to ultimately enhance the efficacy of immunotherapy.

The immune checkpoint TIGIT is upregulated on T cells during bacterial infection and is a potential target for immunotherapy

Antibiotic resistance is a major public health threat, and alternatives to antibiotic therapy are urgently needed. Immunotherapy, particularly the blockade of inhibitory immune checkpoints, is a leading treatment option in cancer and autoimmunity. In this study, we used a murine model of Salmonella Typhimurium infection to investigate whether immune checkpoint blockade could be applied to bacterial infection. We found that the immune checkpoint T-cell immunoglobulin and ITIM domain (TIGIT) was significantly upregulated on lymphocytes during infection, particularly on CD4+ T cells, drastically limiting their proinflammatory function. Blockade of TIGIT in vivo using monoclonal antibodies was able to enhance immunity and improve bacterial clearance. The efficacy of anti-TIGIT was dependent on the capacity of the antibody to bind to Fc (fragment crystallizable) receptors, giving important insights into the mechanism of anti-TIGIT therapy. This research suggests that targeting immune checkpoints, such as TIGIT, has the potential to enhance immune responses toward bacteria and restore antibacterial treatment options in the face of antibiotic resistance.

Non-viral vector-based genome editing for cancer immunotherapy

Despite the exciting promise of cancer immunotherapy in the clinic, immune checkpoint blockade therapy and T cell-based therapies are often associated with low response rates, intrinsic and adaptive immune resistance, and systemic side effects. CRISPR-Cas-based genome editing appears to be an effective strategy to overcome these unmet clinical needs. As a safer delivery platform for the CRISPR-Cas system, non-viral nanoformulations have been recently explored to target tumor cells and immune cells, aiming to improve cancer immunotherapy on a gene level. In this review, we summarized the efforts of non-viral vector-based CRISPR-Cas-mediated genome editing in tumor cells and immune cells for cancer immunotherapy. Their design rationale and specific applications were highlighted.

Exploring the Complexity and Promise of Tumor Immunotherapy in Drug Development

Cancer represents a significant threat to human health, and traditional chemotherapy or cytotoxic therapy is no longer the sole or preferred approach for managing malignant tumors. With advanced research into the immunogenicity of tumor cells and the growing elderly population, tumor immunotherapy has emerged as a prominent therapeutic option. Its significance in treating elderly cancer patients is increasingly recognized. In this study, we review the conceptual classifications and benefits of immunotherapy, and discuss recent developments in new drugs and clinical progress in cancer treatment through various immunotherapeutic modalities with different mechanisms. Additionally, we explore the impact of immunosenescence on the effectiveness of cancer immunotherapy and propose innovative and effective strategies to rejuvenate senescent T cells.

Targeting PD-L1 in cholangiocarcinoma using nanovesicle-based immunotherapy

This study demonstrates the potential of using biological nanoparticles to deliver RNA therapeutics targeting programmed death-ligand 1 (PD-L1) as a treatment strategy for cholangiocarcinoma (CCA). RNA therapeutics offer prospects for intracellular immune modulation, but effective clinical translation requires appropriate delivery strategies. Milk-derived nanovesicles were decorated with epithelial cellular adhesion molecule (EpCAM) aptamers and used to deliver PD-L1 small interfering RNA (siRNA) or Cas9 ribonucleoproteins directly to CCA cells. In vitro, nanovesicle treatments reduced PD-L1 expression in CCA cells while increasing degranulation, cytokine release, and tumor cell cytotoxicity when tumor cells were co-cultured with T cells or natural killer cells. Similarly, immunomodulation was observed in multicellular spheroids that mimicked the tumor microenvironment. Combining targeted therapeutic vesicles loaded with siRNA to PD-L1 with gemcitabine effectively reduced tumor burden in an immunocompetent mouse CCA model compared with controls. This proof-of-concept study demonstrates the potential of engineered targeted nanovesicle platforms for delivering therapeutic RNA cargoes to tumors, as well as their use in generating effective targeted immunomodulatory therapies for difficult-to-treat cancers such as CCA.

Pooled Rate of Pseudoprogression, Patterns of Response, and Tumor Burden Analysis in Patients Undergoing Immunotherapy Oncologic Trials for Different Malignancies

AIMS

Assess rates of true pseudoprogression in unconfirmed progressive disease (iUPD) in a pool of immunotherapy clinical trials for different cancers, analyze tumor characteristics that drive iUPD classification, and investigate potentials predictors of pseudoprogression.

MATERIALS AND METHODS

Retrospective interpretation of prospectively acquired data. Patients from 18 immunotherapy clinical trials with two arms (RECIST 1.1, iRECIST), of 10 cancer types were selected. Pooled rate of true pseudoprogression among iUPD was estimated using a common effect meta-analysis. Target, Non-target, and new lesions as the trigger of confirmed-vs pseudo-progression were compared using Chi-Square and Fisher exact tests. Conditional logistic regression was used to investigate the association between age, sex, tumor burden at baseline, and number of follow ups and pseudoprogression.

RESULTS

60/287 (21%) patients (17 women) were classified as iUPD with at least one subsequent confirmatory timepoint. The overall pooled estimate of pseudoprogression was 15% (95%CI: 8%--26%). Nontarget lesions were significantly more frequent the cause of iUPD than change in Target lesions size (p< 0.001). Most observations of true pseudoprogression occurred in the first follow-up (77%), whereas confirmed progression occurred in later time points during the trial. Pseudoprogression was not significantly associated with age, sex, tumor burden at baseline, or number of timepoints.

CONCLUSION

In a pool of immunotherapy trials, the rate of true pseudoprogression was 15%, most often in the first timepoint after baseline than later in treatment. iUPD categorization was mostly driven by changes in NT lesions rather than objective changes in measurements of target lesions.

Insufficient PD-1 expression during active autoimmune responses: a deep single-cell proteomics analysis in inflammatory arthritis

Objectives

Programmed cell death protein-1 (PD-1) maintains peripheral immune tolerance by preventing T cell continuous activation. Aiming to understand the extent of PD-1 expression in inflammatory arthritis beyond its involvement with T cells, we assess its presence on various circulating single cells.

Methods

Mass cytometry analysis of patients with active seropositive/seronegative rheumatoid (RA; n=9/8) and psoriatic (PsA; n=9) arthritis versus healthy controls (HC; n=13), re-evaluating patients after 3 months of anti-rheumatic treatment.

Results

PD-1 was expressed in all leukocyte subpopulations, with the highest PD-1+ cell frequencies in eosinophils (59-73%) and T cells (50-60%), and the lowest in natural-killer cells (1-3%). PD-1+ cell frequencies and PD-1 median expression were comparable between patient subgroups and HC, in the majority of cell subsets. Exceptions included increases in certain T cell/B cell subsets of seropositive RA and specific monocyte subsets and dendritic cells of PsA; an expanded PD-1+CD4+CD45RA+CD27+CD28+ T subset, denoting exhausted T cells, was common across patient subgroups. Strikingly, significant inverse correlations between individual biomarkers of systemic inflammation (ESR and/or serum CRP) and PD-1+ cell frequencies and/or median expression were evident in several innate and adaptive immunity cell subsets of RA and PsA patients. Furthermore, all inverse correlations noted in individuals with active arthritis were no longer discernible in those who attained remission/low disease activity post-treatment.

Conclusion

PD-1 expression may be insufficient, relative to the magnitude of the concomitant systemic inflammatory response on distinct leukocyte subsets, varying between RA and PsA. Our results point to the potential therapeutic benefits of pharmacological PD-1 activation, to rebalance the autoimmune response and reduce inflammation.

The impact of antibiotic use in gastrointestinal tumors treated with immune checkpoint inhibitors: systematic review and meta-analysis

Background

Immune checkpoint inhibitors (ICI) have improved overall survival in patients with different cancer types. However, treatment efficacy varies between patients depending on several factors. Recent research suggested that antibiotic-induced dysbiosis can impair ICI efficacy. Here we review the impact of antibiotic use in clinical outcome of patients with gastrointestinal cancer treated with ICI.

Methods

This is a systematic review and utilized a thorough search of MEDLINE, Cochrane, Scopus, EB-SCO, Web of Science of studies published till September 2023. The aim of the study is to determine the association between antibiotic use and ICI treatment efficacy in patients with gastrointestinal cancers (GI). We utilized a meta-analysis of the association between the use of antibiotics and overall survival and progression-free survival.

Results

Nine studies met the inclusion criteria with a total of 2,214 patients. The most common type of cancers was hepatocellular carcinoma (HCC). The majority of the studies were retrospective, and one was collective of clinical trials. The use of antibiotics was associated with decreased both overall survival [haz-ard ratio (HR) 1.92, 95% confidence interval (CI) 1.41, 2.63] and progression-free survival [HR 1.81, 95% CI 1.29, 2.54].

Conclusion

The use of antibiotics may affect clinical outcomes in patients with GI cancers treated with ICI. Further prospective studies are needed to improve the understanding of this phenomenon.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023462172.

Immune checkpoint inhibitors and neurotoxicity: a focus on diagnosis and management for a multidisciplinary approach

INTRODUCTION

Although immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment, the consequential over activation of the immune system is often complicated by adverse events that can affect several organs and systems, including the nervous system. The precise pathophysiology underlying neurological irAEs (n-irAEs) is not completely known. Around 3.8% of patients receiving anti-CTLA-4 agents, 6.1% of patients receiving anti-PD-1/PD-L1, and 12% of patients receiving combination therapies have n-irAEs. Most n-irAEs are low-grade, while severe toxicities have rarely been reported. in this article, we performed an updated literature search on immuno-related neurotoxicity on main medical research database, from February 2017 to December 2023.

AREAS COVERED

We have also compared the latest national and international guidelines on n-irAEs management with each other in order to better define patient management.

EXPERT OPINION

A multidisciplinary approach appears necessary in the management of oncological patients during immunotherapy. Therefore, in order to better manage these toxicities, we believe that it is essential to collaborate with neurologists specialized in the diagnosis and treatment of n-irAEs, and that a global neurological assessment, both central and peripheral, is necessary before starting immunotherapy, with regular reassessment during treatment.

Nanodrugs based on co-delivery strategies to combat cisplatin resistance

Cisplatin (CDDP), as a broad-spectrum anticancer drug, is able to bind to DNA and inhibit cell division. Despite the widespread use of cisplatin since its discovery, cisplatin resistance developed during prolonged chemotherapy, similar to other small molecule chemotherapeutic agents, severely limits its clinical application. Cisplatin resistance in cancer cells is mainly caused by three reasons: DNA repair, decreased cisplatin uptake/increased efflux, and cisplatin inactivation. In earlier combination therapies, the emergence of multidrug resistance (MDR) in cancer cells prevented the achievement of the desired therapeutic effect even with the accurate combination of two chemotherapeutic drugs. Therefore, combination therapy using nanocarriers for co-delivery of drugs is considered to be ideal for alleviating cisplatin resistance and reducing cisplatin-related toxicity in cancer cells. This article provides an overview of the design of cisplatin nano-drugs used to combat cancer cell resistance, elucidates the mechanisms of action of cisplatin and the pathways through which cancer cells develop resistance, and finally discusses the design of drugs and related carriers that can synergistically reduce cancer resistance when combined with cisplatin.

Immune checkpoint molecules in solid organ transplantation: A promising way to prevent rejection

Immune checkpoint (IC) molecules modulate immune responses upon antigen presentation; the interaction between different IC molecules will result in the stimulation or, rather, the thwarting of such responses. Tumor cells express increased amounts of inhibitory IC molecules in an attempt to evade immune responses; therapeutic agents have been developed that bind inhibitory IC molecules, restoring tumor-directed immune responses and changing the prognosis of a number of cancers. Stimulation of inhibitory IC molecules could be beneficial in preventing rejection in the setting of solid organ transplantation (SOT), and in vivo as well as in vivo results obtained in animal models show this to indeed to be the case. With the exception of belatacept, a monoclonal antibody (mAb) in which an IgG Fc fragment is linked to the extracellular domain of CTLA-4, this has not yet translated into the generation of novel therapeutic approaches to prevent SOT rejection. We provide a review of state-of-the art knowledge on the role played by IC molecules in transplantation, confident that innovative research will lead to new avenues to manage rejection in solid organ transplant.

Knocking down of Xkr8 enhances chemotherapy efficacy through modulating tumor immune microenvironment

Scramblase Xk-related protein 8 (Xkr8) regulates the externalization of phosphatidylserine (PS) during apoptosis and holds a pivotal role in fostering tumor immunosuppression. Targeting Xkr8 in conjunction with chemotherapy demonstrated a novel avenue for amplifying antitumor immune response and overcoming chemo-immune resistance. Here we further evaluated this strategy by using a clinically relevant orthotopic model and elucidated the mechanism through in-depth single-cell RNA sequencing (scRNA-seq). We found that Xkr8 knockdown exhibited the potential to lead to immunogenic cell death (ICD) by impeding the normal clearance of apoptotic cells. Co-delivery of Xkr8 small interference RNA (siRNA) and a prodrug conjugate of 5-fluorouracil (5-Fu) and oxoplatin (FuOXP) showed remarkable therapeutic efficacy in an orthotopic pancreatic tumor model with increased infiltration of proliferative NK cells and activated macrophages in the tumor microenvironment (TME). Single-cell trajectory analysis further unveiled that tumor infiltrating CD8+ T cells are differentiated favorably to cytotoxic over exhausted phenotype after combination treatment. Our study sheds new light on the impact of Xkr8 knockdown on TME and solidifies the rationale of combining Xkr8 knockdown with chemotherapy to treat various types of cancers.

A systematic review of immunotherapy in high-grade glioma: learning from the past to shape future perspectives

High-grade gliomas (HGGs) constitute the most common malignant primary brain tumor with a poor prognosis despite the standard multimodal therapy. In recent years, immunotherapy has changed the prognosis of many cancers, increasing the hope for HGG therapy. We conducted a comprehensive search on PubMed, Scopus, Embase, and Web of Science databases to include relevant studies. This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Fifty-two papers were finally included (44 phase II and eight phase III clinical trials) and further divided into four different subgroups: 14 peptide vaccine trials, 15 dendritic cell vaccination (DCV) trials, six immune checkpoint inhibitor (ICI) trials, and 17 miscellaneous group trials that included both "active" and "passive" immunotherapies. In the last decade, immunotherapy created great hope to increase the survival of patients affected by HGGs; however, it has yielded mostly dismal results in the setting of phase III clinical trials. An in-depth analysis of these clinical results provides clues about common patterns that have led to failures at the clinical level and helps shape the perspective for the next generation of immunotherapies in neuro-oncology.

A 67-Year-Old Man with Grade 3 Reactive Cutaneous Capillary Endothelial Proliferation Induced by Camrelizumab First Manifested in the Oral Mucosa - A Case Report

Reactive cutaneous capillary endothelial proliferation (RCCEP) is the most common immune-related adverse event induced by camrelizumab (SHR-1210). Very rare cases have been reported in oral tissues, especially the oral mucosa. We reported a 67-year-old male with Grade 3 RCCEP. Multiple dome-shaped and bright red papules were first observed in the oral mucosa, which gradually developed on his lip, face, scalp, neck, foot, calf, abdomen and groin. The patient's symptoms gradually improved at 4 weeks after SHR-1210 discontinuation and were mostly relieved at 7 weeks after discontinuation. Our findings revealed that oral examination should be performed regularly during SHR-1210 treatment.

Comprehensive prognostic assessment in kidney cancer: A multidimensional approach analyzing Fufang Sanling granules, genetic variants, and immune infiltration

This study delves into the potential therapeutic benefits of Fufang Sanling Granules for kidney cancer, focusing on their active components and the underlying mechanisms of their interaction with cancer-related targets. By constructing a drug-active component-target network based on eight herbs, key active compounds such as kaempferol, quercetin, and linolenic acid were identified, suggesting their pivotal roles in modulating immune responses and cellular signaling pathways relevant to cancer progression. The research further identified 51 central drug-disease genes through comprehensive bioinformatics analyses, implicating their involvement in crucial biological processes and pathways. A novel risk score model, encompassing six genes with significant prognostic value for renal cancer, was established and validated, showcasing its effectiveness in predicting patient outcomes through mutation analysis and survival studies. The model's predictive power was further confirmed by its ability to stratify patients into distinct risk groups with significant survival differences, highlighting its potential as a prognostic tool. Additionally, the study explored the relationship between gene expression within the identified black module and the risk score, uncovering significant associations with the extracellular matrix and immune infiltration patterns. This reveals the complex interplay between the tumor microenvironment and cancer progression. The integration of the risk score with clinical parameters through a nomogram significantly improved the model's predictive accuracy, offering a more comprehensive tool for predicting kidney cancer prognosis. In summary, by combining detailed molecular analyses with clinical insights, this study presents a robust framework for understanding the therapeutic potential of Fufang Sanling Granules in kidney cancer. It not only sheds light on the active components and their interactions with cancer-related genes but also introduces a reliable risk score model, paving the way for personalized treatment strategies and improved patient management in the future.

Non-viral expression of chimeric antigen receptors with multiplex gene editing in primary T cells

Efficient engineering of T cells to express exogenous tumor-targeting receptors such as chimeric antigen receptors (CARs) or T-cell receptors (TCRs) is a key requirement of effective adoptive cell therapy for cancer. Genome editing technologies, such as CRISPR/Cas9, can further alter the functional characteristics of therapeutic T cells through the knockout of genes of interest while knocking in synthetic receptors that can recognize cancer cells. Performing multiple rounds of gene transfer with precise genome editing, termed multiplexing, remains a key challenge, especially for non-viral delivery platforms. Here, we demonstrate the efficient production of primary human T cells incorporating the knockout of three clinically relevant genes (B2M, TRAC, and PD1) along with the non-viral transfection of a CAR targeting disialoganglioside GD2. Multiplexed knockout results in high on-target deletion for all three genes, with low off-target editing and chromosome alterations. Incorporating non-viral delivery to knock in a GD2-CAR resulted in a TRAC-B2M-PD1-deficient GD2 CAR T-cell product with a central memory cell phenotype and high cytotoxicity against GD2-expressing neuroblastoma target cells. Multiplexed gene-editing with non-viral delivery by CRISPR/Cas9 is feasible and safe, with a high potential for rapid and efficient manufacturing of highly potent allogeneic CAR T-cell products.

Immune Checkpoint Inhibitors in Hepatocellular Carcinoma and Their Hepatic-Related Side Effects: A Review

Primary liver cancer is one of the leading causes of cancer mortality worldwide, with hepatocellular carcinoma (HCC) being the most prevalent type of liver cancer. The prognosis of patients with advanced, unresectable HCC has historically been poor. However, with the emergence of immunotherapy, specifically immune checkpoint inhibitors (ICIs), there is reason for optimism. Nevertheless, ICIs do not come without risk, especially when administered in patients with HCC, given their potential underlying poor hepatic reserve. Given their novelty in the management of HCC, there are few studies to date specifically investigating ICI-related side effects on the liver in patients with underlying HCC. This review will serve as a guide for clinicians on ICIs' role in the management of HCC and their potential side effect profile. There will be a discussion on ICI-related hepatotoxicity, the potential for hepatitis B and C reactivation with ICI use, the potential for the development of autoimmune hepatitis with ICI use, and the risk of gastrointestinal bleeding with ICI use. As ICIs become more commonplace as a treatment option in patients with advanced HCC, it is imperative that clinicians not only understand the mechanism of action of such agents but also understand and are able to identify hepatic-related side effects.

Apoptosis, a Metabolic "Head-to-Head" between Tumor and T Cells: Implications for Immunotherapy

Induction of apoptosis represents a promising therapeutic approach to drive tumor cells to death. However, this poses challenges due to the intricate nature of cancer biology and the mechanisms employed by cancer cells to survive and escape immune surveillance. Furthermore, molecules released from apoptotic cells and phagocytes in the tumor microenvironment (TME) can facilitate cancer progression and immune evasion. Apoptosis is also a pivotal mechanism in modulating the strength and duration of anti-tumor T-cell responses. Combined strategies including molecular targeting of apoptosis, promoting immunogenic cell death, modulating immunosuppressive cells, and affecting energy pathways can potentially overcome resistance and enhance therapeutic outcomes. Thus, an effective approach for targeting apoptosis within the TME should delicately balance the selective induction of apoptosis in tumor cells, while safeguarding survival, metabolic changes, and functionality of T cells targeting crucial molecular pathways involved in T-cell apoptosis regulation. Enhancing the persistence and effectiveness of T cells may bolster a more resilient and enduring anti-tumor immune response, ultimately advancing therapeutic outcomes in cancer treatment. This review delves into the pivotal topics of this multifaceted issue and suggests drugs and druggable targets for possible combined therapies.

Safety of immune checkpoint inhibitors: An updated comprehensive disproportionality analysis and meta-analysis

BACKGROUND

The exact safety profile of Immune checkpoint inhibitors (ICIs) is unclear so far.

AIM

The aim of the current study is to analyse the safety profile of ICIs in cancer patients.

METHODOLOGY

The updated comprehensive disproportionality analysis of post-marketing data using the FAERS database and meta-analysis of randomized clinical trials (RCTs) was conducted. Disproportionality measures were calculated in terms of PRR associated with chi-square value and ROR with 95% confidence intervals whereas overall estimate measures with 95% CIs, publication bias and heterogeneity were calculated using RevMan 5.4. The GRADE analysis was also done to check the quality of evidence for each outcome.

RESULTS

Various novel signals such as cholangitis, encephalitis, anuria, myelosuppression, and cachexia related to different system organ class were identified with ICIs. The sensitivity analysis results have indicated the influence of concomitant drugs on the identified signals. The meta-analysis results have shown a good safety profile of atezolizumab in non-small cell lung cancer (NSCLC) and melanoma, pembrolizumab in gastro-oesophageal cancer, urothelial cancer and head and neck squamous cell carcinoma (HNSCC), nivolumab in HNSCC as compared to the non-ICI group.

CONCLUSION

The safety of ICIs is dependent on their types as well as on the types of cancer.

The recent advancement of TCR-T cell therapies for cancer treatment

Adoptive cell therapies involve infusing engineered immune cells into cancer patients to recognize and eliminate tumor cells. Adoptive cell therapy, as a form of living drug, has undergone explosive growth over the past decade. The recognition of tumor antigens by the T-cell receptor (TCR) is one of the natural mechanisms that the immune system used to eliminate tumor cells. TCR-T cell therapy, which involves introducing exogenous TCRs into patients' T cells, is a novel cell therapy strategy. TCR-T cell therapy can target the entire proteome of cancer cells. Engineering T cells with exogenous TCRs to help patients combat cancer has achieved success in clinical trials, particularly in treating solid tumors. In this review, we examine the progress of TCR-T cell therapy over the past five years. This includes the discovery of new tumor antigens, protein engineering techniques for TCR, reprogramming strategies for TCR-T cell therapy, clinical studies on TCR-T cell therapy, and the advancement of TCR-T cell therapy in China. We also propose several potential directions for the future development of TCR-T cell therapy.

Checkpoint Inhibitors in Dogs: Are We There Yet?

Immune checkpoint inhibitors (ICI) have revolutionised cancer treatment in people. Immune checkpoints are important regulators of the body's reaction to immunological stimuli. The most studied immune checkpoint molecules are programmed death (PD-1) with its ligand (PD-L1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) with its ligands CD80 (B7-1) and CD86 (B7-2). Certain tumours can evade immunosurveillance by activating these immunological checkpoint targets. These proteins are often upregulated in cancer cells and tumour-infiltrating lymphocytes, allowing cancer cells to evade immune surveillance and promote tumour growth. By blocking inhibitory checkpoints, ICI can help restore the immune system to effectively fight cancer. Several studies have investigated the expression of these and other immune checkpoints in human cancers and have shown their potential as therapeutic targets. In recent years, there has been growing interest in studying the expression of immune checkpoints in dogs with cancer, and a few small clinical trials with ICI have already been performed on these species. Emerging studies in veterinary oncology are centred around developing and validating canine-targeted antibodies. Among ICIs, anti-PD-1 and anti-PD-L1 treatments stand out as the most promising, mirroring the success in human medicine over the past decade. Nevertheless, the efficacy of caninized antibodies remains suboptimal, especially for canine oral melanoma. To enhance the utilisation of ICIs, the identification of predictive biomarkers for treatment response and the thorough screening of individual tumours are crucial. Such endeavours hold promise for advancing personalised medicine within veterinary practice, thereby improving treatment outcomes. This article aims to review the current research literature about the expression of immune checkpoints in canine cancer and the current results of ICI treatment in dogs.

Current Progress in the Science of Novel Adjuvant Nano-Vaccine-Induced Protective Immune Responses

Vaccinations are vital as they protect us from various illness-causing agents. Despite all the advancements in vaccine-related research, developing improved and safer vaccines against devastating infectious diseases including Ebola, tuberculosis and acquired immune deficiency syndrome (AIDS) remains a significant challenge. In addition, some of the current human vaccines can cause adverse reactions in some individuals, which limits their use for massive vaccination program. Therefore, it is necessary to design optimal vaccine candidates that can elicit appropriate immune responses but do not induce side effects. Subunit vaccines are relatively safe for the vaccination of humans, but they are unable to trigger an optimal protective immune response without an adjuvant. Although different types of adjuvants have been used for the formulation of vaccines to fight pathogens that have high antigenic diversity, due to the toxicity and safety issues associated with human-specific adjuvants, there are only a few adjuvants that have been approved for the formulation of human vaccines. Recently, nanoparticles (NPs) have gain specific attention and are commonly used as adjuvants for vaccine development as well as for drug delivery due to their excellent immune modulation properties. This review will focus on the current state of adjuvants in vaccine development, the mechanisms of human-compatible adjuvants and future research directions. We hope this review will provide valuable information to discovery novel adjuvants and drug delivery systems for developing novel vaccines and treatments.

TWIST1 Drives Cytotoxic CD8+ T-Cell Exhaustion through Transcriptional Activation of CD274 (PD-L1) Expression in Breast Cancer Cells

In breast cancer, epithelial-mesenchymal transition (EMT) is positively associated with programmed death ligand 1 (PD-L1) expression and immune escape, and TWIST1 silences ERα expression and induces EMT and cancer metastasis. However, how TWIST1 regulates PD-L1 and immune evasion is unknown. This study analyzed TWIST1 and PD-L1 expression in breast cancers, investigated the mechanism for TWIST1 to regulate PD-L1 transcription, and assessed the effects of TWIST1 and PD-L1 in cancer cells on cytotoxic CD8+ T cells. Interestingly, TWIST1 expression is correlated with high-level PD-L1 expression in ERα-negative breast cancer cells. The overexpression and knockdown of TWIST1 robustly upregulate and downregulate PD-L1 expression, respectively. TWIST1 binds to the PD-L1 promoter and recruits the TIP60 acetyltransferase complex in a BRD8-dependent manner to transcriptionally activate PD-L1 expression, which significantly accelerates the exhaustion and death of the cytotoxic CD8+ T cells. Accordingly, knockdown of TWIST1 or BRD8 or inhibition of PD-L1 significantly enhances the tumor antigen-specific CD8+ T cells to suppress the growth of breast cancer cells. These results demonstrate that TWIST1 directly induces PD-L1 expression in ERα-negative breast cancer cells to promote immune evasion. Targeting TWIST1, BRD8, and/or PD-L1 in ERα-negative breast cancer cells with TWIST1 expression may sensitize CD8+ T-cell-mediated immunotherapy.

Utilizing a Proximity Dependent Labeling Strategy to Study Cancer-Immune Intercellular Interactions In Vitro and In Vivo

Immune cells play a critical role in surveilling and defending against cancer, emphasizing the importance of understanding how they interact and communicate with cancer cells to determine cancer status, treatment response, and the formation of the tumor microenvironment (TME). To this end, we conducted a study demonstrating the effectiveness of an enzyme-mediated intercellular proximity labeling (EXCELL) method, which utilizes a modified version of the sortase A enzyme known as mgSrtA, in detecting and characterizing immune-tumor cell interactions. The mgSrtA enzyme is expressed on the membrane of tumor cells, which is able to label immune cells that interact with tumor cells in a proximity-dependent manner. Our research indicates that the EXCELL technique can detect and characterize immune-tumor cell interactions in a time- and concentration-dependent manner, both in vitro and in vivo, without requiring pre-engineering of the immune cells. We also highlight its ability to detect various types of immune cell subpopulations in vivo that have migrated out of the tumor into the spleen, providing insights into the role of peripheral T-cell recruitment in tumor progression. Overall, our findings suggest that the EXCELL method has great potential for improving our understanding of immune cell dynamics within the TME, ultimately leading to more potent pharmacological effects and cancer immunotherapy strategies. SIGNIFICANCE STATEMENT: The enzyme-mediated intercellular proximity labeling method holds promise for detecting immune cell interactions with cancer cells, both in vitro and in vivo. It has important implications for studying immune tumor cell dynamics and potentially uncovering novel subtypes of immune cells within the tumor microenvironment, both prior to and during immunotherapeutic interventions.

The role of extracellular vesicle immune checkpoints in cancer

Immune checkpoints (ICPs) play a crucial role in regulating the immune response. In the tumor, malignant cells can hijack the immunosuppressive effects of inhibitory ICPs to promote tumor progression. Extracellular vesicles (EVs) are produced by a variety of cells and contain bioactive molecules on their surface or within their lumen. The expression of ICPs has also been detected in EVs. In vitro and in vivo studies have shown that extracellular vesicle immune checkpoints (EV ICPs) have immunomodulatory effects and are involved in tumor immunity. EV ICPs isolated from the peripheral blood of cancer patients are closely associated with the tumor progression and the prognosis of cancer patients. Blocking inhibitory ICPs has been recognized as an effective strategy in cancer treatment. However, the efficacy of immune checkpoint inhibitors (ICIs) in cancer treatment is hindered by the emergence of therapeutic resistance, which limits their widespread use. Researchers have demonstrated that EV ICPs are correlated with clinical response to ICIs therapy and were involved in therapeutic resistance. Therefore, it is essential to investigate the immunomodulatory effects, underlying mechanisms, and clinical significance of EV ICPs in cancer. This review aims to comprehensively explore these aspects. We have provided a comprehensive description of the cellular origins, immunomodulatory effects, and clinical significance of EV ICPs in cancer, based on relevant studies.

The synergistic immunotherapeutic impact of engineered CAR-T cells with PD-1 blockade in lymphomas and solid tumors: a systematic review

Currently, therapies such as chimeric antigen receptor-T Cell (CAR-T) and immune checkpoint inhibitors like programmed cell death protein-1 (PD-1) blockers are showing promising results for numerous cancer patients. However, significant advancements are required before CAR-T therapies become readily available as off-the-shelf treatments, particularly for solid tumors and lymphomas. In this review, we have systematically analyzed the combination therapy involving engineered CAR-T cells and anti PD-1 agents. This approach aims at overcoming the limitations of current treatments and offers potential advantages such as enhanced tumor inhibition, alleviated T-cell exhaustion, heightened T-cell activation, and minimized toxicity. The integration of CAR-T therapy, which targets tumor-associated antigens, with PD-1 blockade augments T-cell function and mitigates immune suppression within the tumor microenvironment. To assess the impact of combination therapy on various tumors and lymphomas, we categorized them based on six major tumor-associated antigens: mesothelin, disialoganglioside GD-2, CD-19, CD-22, CD-133, and CD-30, which are present in different tumor types. We evaluated the efficacy, complete and partial responses, and progression-free survival in both pre-clinical and clinical models. Additionally, we discussed potential implications, including the feasibility of combination immunotherapies, emphasizing the importance of ongoing research to optimize treatment strategies and improve outcomes for cancer patients. Overall, we believe combining CAR-T therapy with PD-1 blockade holds promise for the next generation of cancer immunotherapy.

Development of small molecule drugs targeting immune checkpoints

Immune checkpoint inhibitors (ICIs) are used to relieve and refuel anti-tumor immunity by blocking the interaction, transcription, and translation of co-inhibitory immune checkpoints or degrading co-inhibitory immune checkpoints. Thousands of small molecule drugs or biological materials, especially antibody-based ICIs, are actively being studied and antibodies are currently widely used. Limitations, such as anti-tumor efficacy, poor membrane permeability, and unneglected tolerance issues of antibody-based ICIs, remain evident but are thought to be overcome by small molecule drugs. Recent structural studies have broadened the scope of candidate immune checkpoint molecules, as well as innovative chemical inhibitors. By way of comparison, small molecule drug-based ICIs represent superior oral bioavailability and favorable pharmacokinetic features. Several ongoing clinical trials are exploring the synergetic effect of ICIs and other therapeutic strategies based on multiple ICI functions, including immune regulation, anti-angiogenesis, and cell cycle regulation. In this review we summarized the current progression of small molecule ICIs and the mechanism underlying immune checkpoint proteins, which will lay the foundation for further exploration.

Current immunotherapeutic approaches to diffuse intrinsic pontine glioma

Diffuse intrinsic pontine glioma (DIPG) is an aggressive brain tumour that occurs in the pons of the brainstem and accounts for over 80% of all brainstem gliomas. The median age at diagnosis is 6-7 years old, with less than 10% overall survival 2 years after diagnosis and less than 1% after 5 years. DIPGs are surgically inaccessible, and radiation therapy provides only transient benefit, with death ensuing from relentless local tumour infiltration. DIPGs are now the leading cause of brain tumour deaths in children, with a societal cancer burden in years of life lost (YLL) of more than 67 per individual, versus approximately 14 and 16 YLL for lung and breast cancer respectively. More than 95 clinical drug trials have been conducted on children with DIPGs, and all have failed to improve survival. No single or combination chemotherapeutic strategy has been successful to date because of our inability to identify targeted drugs for this disease and to deliver these drugs across an intact blood-brain barrier (BBB). Accordingly, there has been an increased focus on immunotherapy research in DIPG, with explorations into treatments such as chimeric antigen receptor T (CAR-T) cells, immune checkpoint blockades, cancer vaccines, and autologous cell transfer therapy. Here, we review the most recent advances in identifying genetic factors influencing the development of immunotherapy for DIPG. Additionally, we explore emerging technologies such as Magnetic Resonance-guided Focused Ultrasound (MRgFUS) in potential combinatorial approaches to treat DIPG.

Prognostic Value of B7H4 Expression in Patients with Solid Cancers: A Systematic Review and Meta-Analysis

V-set domain-containing T-cell activation inhibitor 1 (aliases VTCN1, B7H4) participates in tumour immune escape by delivering inhibitory signals to T cells. The purpose of this article was to assess the B7H4 prognostic value in solid cancers. Three databases were searched for relevant articles. The main endpoints were overall survival (OS), disease-specific survival (DSS), progression-free survival (PFS), recurrence-free survival (RFS), and disease-free survival (DFS). Appropriate hazard ratios (HRs) were pooled. The R studio software (version 4.0.3) was used for data analysis. Thirty-one studies met the inclusion criteria. High expression of B7H4 was associated with worse OS (HR = 1.52, 95% CI: 1.37-1.68) but not with DSS (HR = 1.14, 95% CI: 0.49-2.63), RFS (HR = 1.77, 95% CI: 0.75-4.18), DFS (HR = 1.29, 95% CI: 0.8-2.09), or PFS (HR = 1.71, 95% CI: 0.91-3.2) in patients with solid cancers. High expression of B7H4 is associated with a poorer prognosis in patients with solid cancers. B7H4 is a promising prognostic biomarker and immunotherapeutic target for various solid cancers because of its activity in cancer immunity and tumourigenesis.

Engineering PD-1-targeted small protein variants for in vitro diagnostics and in vivo PET imaging

BACKGROUND

Programmed cell death 1 (PD-1) belongs to immune checkpoint proteins ensuring negative regulation of the immune response. In non-small cell lung cancer (NSCLC), the sensitivity to treatment with anti-PD-1 therapeutics, and its efficacy, mostly correlated with the increase of tumor infiltrating PD-1+ lymphocytes. Due to solid tumor heterogeneity of PD-1+ populations, novel low molecular weight anti-PD-1 high-affinity diagnostic probes can increase the reliability of expression profiling of PD-1+ tumor infiltrating lymphocytes (TILs) in tumor tissue biopsies and in vivo mapping efficiency using immune-PET imaging.

METHODS

We designed a 13 kDa β-sheet Myomedin scaffold combinatorial library by randomization of 12 mutable residues, and in combination with ribosome display, we identified anti-PD-1 Myomedin variants (MBA ligands) that specifically bound to human and murine PD-1-transfected HEK293T cells and human SUP-T1 cells spontaneously overexpressing cell surface PD-1.

RESULTS

Binding affinity to cell-surface expressed human and murine PD-1 on transfected HEK293T cells was measured by fluorescence with LigandTracer and resulted in the selection of most promising variants MBA066 (hPD-1 KD = 6.9 nM; mPD-1 KD = 40.5 nM), MBA197 (hPD-1 KD = 29.7 nM; mPD-1 KD = 21.4 nM) and MBA414 (hPD-1 KD = 8.6 nM; mPD-1 KD = 2.4 nM). The potential of MBA proteins for imaging of PD-1+ populations in vivo was demonstrated using deferoxamine-conjugated MBA labeled with 68Galium isotope. Radiochemical purity of 68Ga-MBA proteins reached values 94.7-99.3% and in vitro stability in human serum after 120 min was in the range 94.6-98.2%. The distribution of 68Ga-MBA proteins in mice was monitored using whole-body positron emission tomography combined with computerized tomography (PET/CT) imaging up to 90 min post-injection and post mortem examined in 12 mouse organs. The specificity of MBA proteins was proven by co-staining frozen sections of human tonsils and NSCLC tissue biopsies with anti-PD-1 antibody, and demonstrated their potential for mapping PD-1+ populations in solid tumors.

CONCLUSIONS

Using directed evolution, we developed a unique set of small binding proteins that can improve PD-1 diagnostics in vitro as well as in vivo using PET/CT imaging.

DIRMC: a database of immunotherapy-related molecular characteristics

Cancer immunotherapy has brought about a revolutionary breakthrough in the field of cancer treatment. Immunotherapy has changed the treatment landscape for a variety of solid and hematologic malignancies. To assist researchers in efficiently uncovering valuable information related to cancer immunotherapy, we have presented a manually curated comprehensive database called DIRMC, which focuses on molecular features involved in cancer immunotherapy. All the content was collected manually from published literature, authoritative clinical trial data submitted by clinicians, some databases for drug target prediction such as DrugBank, and some experimentally confirmed high-throughput data sets for the characterization of immune-related molecular interactions in cancer, such as a curated database of T-cell receptor sequences with known antigen specificity (VDJdb), a pathology-associated TCR database (McPAS-TCR) et al. By constructing a fully connected functional network, ranging from cancer-related gene mutations to target genes to translated target proteins to protein regions or sites that may specifically affect protein function, we aim to comprehensively characterize molecular features related to cancer immunotherapy. We have developed the scoring criteria to assess the reliability of each MHC-peptide-T-cell receptor (TCR) interaction item to provide a reference for users. The database provides a user-friendly interface to browse and retrieve data by genes, target proteins, diseases and more. DIRMC also provides a download and submission page for researchers to access data of interest for further investigation or submit new interactions related to cancer immunotherapy targets. Furthermore, DIRMC provides a graphical interface to help users predict the binding affinity between their own peptide of interest and MHC or TCR. This database will provide researchers with a one-stop resource to understand cancer immunotherapy-related targets as well as data on MHC-peptide-TCR interactions. It aims to offer reliable molecular characteristics support for both the analysis of the current status of cancer immunotherapy and the development of new immunotherapy. DIRMC is available at http://www.dirmc.tech/. Database URL: http://www.dirmc.tech/.

NIR Absorbing Organic Chromophores Combination with NSAIDs for Remodeling of the Inflammatory Microenvironment to Amplify Tumor Ferroptosis-Photothermal Synergistic Therapy

Photothermal therapy has emerged as a promising approach for cancer treatment, which can cause ferroptosis to enhance immunotherapeutic efficacy. However, excessively generated immunogenicity will induce serious inflammatory response syndrome, resulting in a discounted therapeutic effect. Herein, a kind of NIR absorption small organic chromophore nanoparticles (TTHM NPs) with high photothermal conversion efficiency (68.33%) is developed, which can induce mitochondria dysfunction, generate mitochondrial superoxide, and following ferroptosis. TTHM NPs-based photothermal therapy is combined with Sulfasalazine (SUZ), a kind of nonsteroidal anti-inflammatory drugs, to weaken inflammation and promote ferroptosis through suppressing glutamate/cystine (Glu/Cys) antiporter system Xc- (xCT). Additionally, the combination of SUZ with PTT can induce immunogenic cell death (ICD), followed by promoting the maturation of DCs and the attraction of CD8+ T cell, which will secrete IFN-γ and trigger self-amplified ferroptosis via inhibiting xCT and simulating Acyl-CoA synthetase long-chain family member 4 (ACSL4). Moreover, the in vivo results demonstrate that this combination therapy can suppress the expression of inflammatory factors, enhance dendritic cell activation, facilitate T-cell infiltration, and realize effective thermal elimination of primary tumors and distant tumors. In general, this work provides an excellent example of combined medication and stimulates new thinking about onco-therapy and inflammatory response.

The cuproptosis-related gene UBE2D2 functions as an immunotherapeutic and prognostic biomarker in pan-cancer

BACKGROUND

Cuproptosis, as a unique modality of regulated cell death, requires the involvement of ubiquitin-binding enzyme UBE2D2. However, the prognostic and immunotherapeutic values of UBE2D2 in pan-cancer remain largely unknown.

METHODS

Using UCSC Xena, TIMER, Clinical Proteomic Tumor Analysis Consortium (CPTAC), and Human Protein Atlas (HPA) databases, we aimed to explore the differential expression pattern of UBE2D2 across multiple cancer types and to evaluate its association with patient prognosis, clinical features, and genetic variations. The association between UBE2D2 and immunotherapy response was assessed by gene set enrichment analysis, tumor microenvironment, immune gene co-expression and drug half maximal inhibitory concentration (IC50) analysis.

RESULTS

The mRNA and protein levels of UBE2D2 were markedly elevated in most cancer types, and UBE2D2 exhibited prognostic significance in liver hepatocellular carcinoma (LIHC), kidney chromophobe (KICH), uveal melanomas (UVM), cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC), and kidney renal papillary cell carcinoma (KIRP). UBE2D2 expression was correlated with clinical features, tumor mutation burden, microsatellite instability, and anti-tumor drug resistance in several tumor types. Gene enrichment analysis showed that UBE2D2 was significantly associated with immune-related pathways. The expression level of UBE2D2 was correlated with immune cell infiltration, including CD4 + T cells、Macrophages M2、CD8 + T cells in pan-cancer. PDCD1, CD274 and CTLA4 expression levels were positively correlated with UBE2D2 level in multiple cancers.

CONCLUSIONS

We comprehensively investigated the potential value of UBE2D2 as a prognostic and immunotherapeutic predictor for pan-cancer, providing a novel insight for cancer immunotherapy.

Frontiers and future of immunotherapy for pancreatic cancer: from molecular mechanisms to clinical application

Pancreatic cancer is a highly aggressive malignant tumor, that is becoming increasingly common in recent years. Despite advances in intensive treatment modalities including surgery, radiotherapy, biological therapy, and targeted therapy, the overall survival rate has not significantly improved in patients with pancreatic cancer. This may be attributed to the insidious onset, unknown pathophysiology, and poor prognosis of the disease. It is therefore essential to identify and develop more effective and safer treatments for pancreatic cancer. Tumor immunotherapy is the new and fourth pillar of anti-tumor therapy after surgery, radiotherapy, and chemotherapy. Significant progress has made in the use of immunotherapy for a wide variety of malignant tumors in recent years; a breakthrough has also been made in the treatment of pancreatic cancer. This review describes the advances in immune checkpoint inhibitors, cancer vaccines, adoptive cell therapy, oncolytic virus, and matrix-depletion therapies for the treatment of pancreatic cancer. At the same time, some new potential biomarkers and potential immunotherapy combinations for pancreatic cancer are discussed. The molecular mechanisms of various immunotherapies have also been elucidated, and their clinical applications have been highlighted. The current challenges associated with immunotherapy and proposed strategies that hold promise in overcoming these limitations have also been discussed, with the aim of offering new insights into immunotherapy for pancreatic cancer.

A potassium-chloride co-transporter with altered genome architecture functions as a suppressor in glioma

Gliomas, the most lethal tumours in brain, have a poor prognosis despite accepting standard treatment. Limited benefits from current therapies can be attributed to genetic, epigenetic and microenvironmental cues that affect cell programming and drive tumour heterogeneity. Through the analysis of Hi-C data, we identified a potassium-chloride co-transporter SLC12A5 associated with disrupted topologically associating domain which was downregulated in tumour tissues. Multiple independent glioma cohorts were included to analyse the characterization of SLC12A5 and found it was significantly associated with pathological features, prognostic value, genomic alterations, transcriptional landscape and drug response. We constructed two SLC12A5 overexpression cell lines to verify the function of SLC12A5 that suppressed tumour cell proliferation and migration in vitro. In addition, SLC12A5 was also positively associated with GABAA receptor activity and negatively associated with pro-tumour immune signatures and immunotherapy response. Collectively, our study provides a comprehensive characterization of SLC12A5 in glioma and supports SLC12A5 as a potential suppressor of disease progression.

Everolimus treatment enhances inhibitory immune checkpoint molecules' expression in monocyte-derived dendritic cells

BACKGROUND

Antigen-specific T-cell immunity is provided by dendritic cells (DCs), which are specialized antigen-presenting cells. Furthermore, they establish a link between innate and adaptive immune responses. Currently, DC modification is a new approach for the therapy of several disorders. During solid organ transplantation, Everolimus, which is a mammalian target of rapamycin (mTOR) inhibitor, was initially utilized to suppress the immune system's functionality. Due to the intervention of Everolimus in various signaling pathways in cells and its modulatory properties on the immune system, this study aims to investigate the effect of treatment with Everolimus on the maturation and expression of immune checkpoint genes in monocyte-derived DCs.

METHODS

To isolate monocytes from PBMCs, the CD14 marker was used via the MACS method. Monocytes were cultured and induced to differentiate into monocyte-derived DCs by utilizing GM-CSF and IL-4 cytokines. On the fifth day, immature DCs were treated with Everolimus and incubated for 24 h. On the sixth day, the flow cytometry technique was used to investigate the effect of Everolimus on the phenotypic characteristics of DCs. In the end, the expression of immune checkpoint genes in both the Everolimus-treated and untreated DCs groups was assessed using the real-time PCR method.

RESULTS

The findings of this research demonstrated that the administration of Everolimus to DCs led to a notable rise in human leukocyte antigen (HLA)-DR expression and a decrease in CD11c expression. Furthermore, there was a significant increase in the expression of immune checkpoint molecules, namely CTLA-4, VISTA, PD-L1, and BTLA, in DCs treated with Everolimus.

CONCLUSION

The findings of this study show that Everolimus can target DCs and affect their phenotype and function in order to shift them toward a partially tolerogenic state. However, additional research is required to gain a comprehensive understanding of the precise impact of Everolimus on the activation status of DCs.

Cancer Nanovaccines: Nanomaterials and Clinical Perspectives

Cancer nanovaccines represent a promising frontier in cancer immunotherapy, utilizing nanotechnology to augment traditional vaccine efficacy. This review comprehensively examines the current state-of-the-art in cancer nanovaccine development, elucidating innovative strategies and technologies employed in their design. It explores both preclinical and clinical advancements, emphasizing key studies demonstrating their potential to elicit robust anti-tumor immune responses. The study encompasses various facets, including integrating biomaterial-based nanocarriers for antigen delivery, adjuvant selection, and the impact of nanoscale properties on vaccine performance. Detailed insights into the complex interplay between the tumor microenvironment and nanovaccine responses are provided, highlighting challenges and opportunities in optimizing therapeutic outcomes. Additionally, the study presents a thorough analysis of ongoing clinical trials, presenting a snapshot of the current clinical landscape. By curating the latest scientific findings and clinical developments, this study aims to serve as a comprehensive resource for researchers and clinicians engaged in advancing cancer immunotherapy. Integrating nanotechnology into vaccine design holds immense promise for revolutionizing cancer treatment paradigms, and this review provides a timely update on the evolving landscape of cancer nanovaccines.