Checkpoint blockade cancer immunotherapy targets tumour-specific mutant antigens

Identification of TTLL8, POTEE, and PKMYT1 as immunogenic cancer-associated antigens and potential immunotherapy targets in ovarian cancer

Most high-grade serous ovarian cancers (OC) do not respond to current immunotherapies. To identify potential new actionable tumor antigens in OC, we performed immunopeptidomics on a human OC cell line expressing the HLA-A02:01 haplotype, which is commonly expressed across many racial and ethnic groups. From this dataset, we identified TTLL8, POTEE, and PKMYT1 peptides as candidate tumor antigens with low expression in normal tissues and upregulated expression in OC. Using tissue microarrays, we assessed the protein expression of TTLL8 and POTEE and their association with patient outcomes in a large cohort of OC patients. TTLL8 was found to be expressed in 56.7% of OC and was associated with a worse overall prognosis. POTEE was expressed in 97.2% of OC patients and had no significant association with survival. In patient TILs, increases in cytokine production and tetramer-positive populations identified antigen-specific CD8 T cell responses, which were dependent on antigen presentation by HLA class I. Antigen-specific T cells triggered cancer cell killing of antigen-pulsed OC cells. These findings suggest that TTLL8, POTEE, and PKMYT1 are potential targets for the development of antigen-targeted immunotherapy in OC.

Shared neoantigens for cancer immunotherapy

Exploration of neoantigens holds the potential to be productive in immuno-oncotherapy. Among tumor-specific antigens, neoantigens result from genetic instability that gives rise to non-synonymous somatic mutations, highly specific to tumor cells. In addition to point mutations, gene rearrangements, indels leading to frameshifts, chromosomal translocations or inversions that may lead to fusion proteins, alternative mRNA splicing, and integration of genetic material of oncogenic viruses into the host genome provide consistent sources of neoantigens that are absent in healthy tissues. Out of these alterations, 2%-3% may generate T cell neoepitopes, possibly detectable by TCRs. Neoantigens are absent in healthy tissues and are thus at low risk of triggering autoimmunity. In addition, the host lymphocytes have not been rendered tolerant toward them and it is possible to induce immune responses against them. Here, we overview the two categories of neoantigens, i.e., private and shared, and their use in immuno-oncotherapy in selected pre-clinical and clinical studies. The vast majority of commonly occurring tumor-specific mutations are cancer causing and are permanently expressed by all malignant tumor cells, preventing the latter from escaping vaccine-induced anti-neoantigen immunity. The use of public neoantigens combined with efficient vaccine platforms can provide non-personalized "off-the-shelf" therapeutic vaccine candidates for broad-spectrum immunotherapy purposes.

A nanoparticle platform for the co-delivery of multiple antigen epitope peptides and STING agonist to lymph nodes for cancer immunotherapy

Nanoparticles loaded with cancer epitope peptides have shown great potential for cancer immunotherapy. However, preparing small-sized nanoparticles with a narrow size distribution for the co-delivery of multiple antigen peptides has been a challenge. The lack of scalable and reproducible nanoparticle preparation methods has also hindered the widespread application of nanoparticles in cancer immunotherapy. In this study, we developed lymph node-targeted nanoparticles for the co-delivery of a group of sixteen pancreatic cancer antigen peptides and a STING agonist as an adjuvant using the flash nanocomplexation (FNC) method. The nanoparticles generated by FNC had a smaller particle size and a narrower size distribution compared to the nanoparticles prepared by bulk mixing. The FNC-generated nanoparticles enhanced human monocyte activation, demonstrated lymph node-targeting effect, and activated dendritic cells in vivo, all without any observable toxicity. Additionally, in vivo studies demonstrated the strong anti-tumor efficacy of these nanoparticles in an orthotopic pancreatic cancer mouse model. This nanoparticle platform enables the effective co-delivery of multiple antigen epitope peptides and an adjuvant to the lymph nodes. Furthermore, the scalability and reproducibility of the FNC method could facilitate the rapid clinical translation of this nanoparticle platform.

Harnessing Exosomes: From Tumor Immune Escape to Therapeutic Innovation in Gastric Cancer Immunotherapy

Gastric cancer ranks fifth among the most prevalent cancers globally, with a dismal prognosis. In recent years, immunotherapy, particularly immune checkpoint inhibitors, has emerged as a glimmer of hope for advanced gastric cancer patients. However, not all patients can benefit from this treatment modality, as the tumor microenvironment significantly influences treatment efficacy. Exosomes, pivotal mediators of intercellular communication, exert intricate and diverse effects in shaping and regulating the tumor microenvironment. This review provides a comprehensive overview of the functional mechanisms of exosomes within the gastric cancer tumor microenvironment. It delves into their biogenesis, functions, and impact on innate and adaptive immune cells (such as dendritic cells, myeloid-derived suppressor cells, and T cells) and cancer-associated fibroblasts. Additionally, the potential applications of exosomes in gastric cancer immunotherapy are explored, including their use as biomarkers to predict responses to immune checkpoint inhibitors, and drug delivery vectors, and in the development of exosome-based vaccines and gene therapy. Notably, this review emphasizes the dual nature of exosomes: they can facilitate tumor immune escape, yet they also serve as promising targets for innovative therapeutic strategies. It also compares potential exosome-based strategies with existing immunotherapies like ICIs and emerging CAR-T cell therapies. Finally, insights into the future of exosomes in precision immunotherapy for gastric cancer are offered, presenting a forward-looking perspective on this emerging field.

Simultaneous co-delivery of Ginsenoside Rg3 and imiquimod from PLGA nanoparticles for effective breast cancer immunotherapy

Breast cancer is a fatal malignancy facing human health, with most patients experiencing recurrence and resistance to chemotherapy. The immunosuppressive tumor microenvironment (TME) greatly limits the actual outcome of immunotherapy. This study aimed to develop a modality of theranostics nanoparticles for breast cancer based on a near-infrared light-triggered nanoparticle for the targeted delivery of ginsenoside Rg3 and immune adjuvants imiquimod (R837) for effective breast cancer immunotherapy. Folate-receptor (FA) targeting IR780-R837/ginsenoside Rg3-perfluorohexane (PFH) @ polyethylene glycol (PEG)-poly (lactide-co-glycolic acid) (PLGA) nanoparticles (FA-NPs) can be activated by near-infrared laser irradiation in tumors, which leads to rapid release of ginsenoside Rg3 and R837 in the regions with high expression of folate receptors and glucose transporter 1 (GLUT1). Meanwhile, the nanoparticles can be used as dual-mode contrast agents for photoacoustic and ultrasound imaging. This strategy provides a strong immune memory effect, which can prevent tumor recurrence after eliminating the initial tumor.

Recent advances in therapeutic cancer vaccines

The success of cancer prevention vaccines targeting cancer-causing viruses has drastically reduced cancer mortality worldwide. However, the development of therapeutic cancer vaccines, which aim to elicit an immune response directly against cancer cells, has faced notable clinical setbacks. In this Review, we explore lessons learned from past cancer vaccine trials and how the field has progressed into an era of renewed promise. Previous vaccines primarily targeted tumour-associated antigens and were mainly tested as monotherapies in late-stage cancers. In contrast, contemporary vaccines focus on targeting tumour-specific antigens (neoantigens) and are showing initial evidence of clinical efficacy, particularly in early-stage cancers and precancers when combined with immune checkpoint inhibitors. Advances in tumour profiling and novel vaccine platforms have enhanced vaccine specificity and potency. We discuss recent clinical trials of therapeutic cancer vaccines and outline future directions for the field.

Translation dysregulation in cancer as a source for targetable antigens

Aberrant peptides presented by major histocompatibility complex (MHC) molecules are targets for tumor eradication, as these peptides can be recognized as foreign by T cells. Protein synthesis in malignant cells is dysregulated, which may result in the generation and presentation of aberrant peptides that can be exploited for T cell-based therapies. To investigate the role of translational dysregulation in immunological tumor control, we disrupt translation fidelity by deleting tRNA wybutosine (yW)-synthesizing protein 2 (TYW2) in tumor cells and characterize the downstream impact on translation fidelity and immunogenicity using immunopeptidomics, genomics, and functional assays. These analyses reveal that TYW2 knockout (KO) cells generate immunogenic out-of-frame peptides. Furthermore, Tyw2 loss increases tumor immunogenicity and leads to anti-programmed cell death 1 (PD-1) checkpoint blockade sensitivity in vivo. Importantly, reduced TYW2 expression is associated with increased response to checkpoint blockade in patients. Together, we demonstrate that defects in translation fidelity drive tumor immunogenicity and may be leveraged for cancer immunotherapy.

Atezolizumab plus personalized neoantigen vaccination in urothelial cancer: a phase 1 trial

Features of constrained adaptive immunity and high neoantigen burden have been correlated with response to immune checkpoint inhibitors (ICIs). In an attempt to stimulate antitumor immunity, we evaluated atezolizumab (anti-programmed cell death protein 1 ligand 1) in combination with PGV001, a personalized neoantigen vaccine, in participants with urothelial cancer. The primary endpoints were feasibility (as defined by neoantigen identification, peptide synthesis, vaccine production time and vaccine administration) and safety. Secondary endpoints included objective response rate, duration of response and progression-free survival for participants treated in the metastatic setting, time to progression for participants treated in the adjuvant setting, overall survival and vaccine-induced neoantigen-specific T cell immunity. A vaccine was successfully prepared (median 20.3 weeks) for 10 of 12 enrolled participants. All participants initiating treatment completed the priming cycle. The most common treatment-related adverse events were grade 1 injection site reactions, fatigue and fever. At a median follow-up of 39 months, three of four participants treated in the adjuvant setting were free of recurrence and two of five participants treated in the metastatic setting with measurable disease achieved an objective response. All participants demonstrated on-treatment emergence of neoantigen-specific T cell responses. Neoantigen vaccination plus ICI was feasible and safe, meeting its endpoints, and warrants further investigation. ClinicalTrials.gov registration: NCT03359239 .

A phase 2 trial of pembrolizumab for recurrent Lynch-like versus sporadic endometrial cancers with microsatellite instability (NCT02899793): Updated survival and response analyses

OBJECTIVE

Microsatellite instability-high (MSI-H)/mismatch repair deficiency (dMMR) is a biomarker for response to immune checkpoint inhibitors. We report updated results including objective response rate, progression free survival, and overall survival data with 5-year follow-up in recurrent platinum-resistant, MSI-H, endometrial cancer (EC) patients fully sequenced using whole exome sequencing (WES) and treated within a prospective phase II study with pembrolizumab (NCT02899793).

METHODS

Tumors from patients with measurable MSI-H/dMMR endometrial cancer confirmed by immunohistochemistry, polymerase chain reaction, and MLH-1 methylation assays were sequenced using whole exome sequencing and the FoundationOne platform for the identification of Lynch, Lynch-like, and MLH-1 methylated characteristics before receiving pembrolizumab 200 mg every 3 weeks for up to 24 months. The primary endpoint was objective response rate (ORR), and secondary endpoints were progression free survival (PFS), and overall survival (OS).

RESULTS

After almost 97 person-years of follow-up, the Lynch-like subgroup (n = 6) of MSI-H/dMMR patients continues to exhibit better ORR than the methylated (n = 18) subgroup (100 % versus 44 %, Fisher's exact P = 0.024), as well as improved PFS (unreached for Lynch-like versus 14.6 months, Log-Rank P = 0.005) and improved OS (unreached for Lynch-like versus 32.6 months, Log-Rank P = 0.058). Toxicity was manageable in both groups of MSI-H patients.

CONCLUSION

Mature follow-up results continue to suggest the prognostic significance of Lynch-like versus methylated MSI-H/dMMR features in endometrial cancer patients treated with pembrolizumab in terms of ORR, PFS, and OS. Stratification for these translational aspects may be warranted in future clinical trials with immune checkpoint inhibitors in MSI-H/dMMR endometrial cancer patients.

PCK1 inhibits cGAS-STING activation by consumption of GTP to promote tumor immune evasion

Hypoxia induces immunosuppressive phenotypes in tumor cells even in the presence of cytosolic DNA accumulation. The mechanisms by which tumor cells suppress hypoxia-induced cGAS-STING activation for immune evasion remain largely unclear. Here, we demonstrate that hypoxic stimulation induces JNK1/2-mediated S151 phosphorylation of phosphoenolpyruvate carboxykinase 1 (PCK1), a rate-limiting enzyme in gluconeogenesis. This phosphorylation triggers the interaction between PCK1 and cGAS. The PCK1 associated with cGAS competitively consumes GTP, a substrate shared by both PCK1 and cGAS. Consequently, PCK1 inhibits GTP-dependent cGAS activation and subsequent STING-promoted immune cell infiltration and activation in the tumor microenvironment, leading to promoted tumor growth in mice. The blockade of PCK1 function, in combination with anti-PD-1 antibody treatment, exhibits an additive therapeutic effect on tumor growth. Additionally, PCK1 S151 phosphorylation is inversely correlated with cGAS-STING activation in human breast cancer specimens and patient survival. These findings reveal a novel regulation of cGAS-STING pathway and uncover the metabolic control of immune response in tumor cells.

Enhanced efficiency of MHC class II tumor neoantigen vaccines with a novel CD4+ T-cell helper epitope

Tumor neoantigens, defined as tumor-specific antigens arising from somatic mutations, have shown great potential as targets for cancer vaccines in clinical studies. However, the number of neoantigens capable of effectively activating immune responses is quite limited. Over the past few decades, tumor neoantigen vaccines based on MHC-I epitopes that activate CD8+ T cells have been extensively studied. However, growing evidence suggests that CD4+ T cells are important in cancer immunotherapy. In contrast to CD8+ T cells, the receptors on CD4+ T cells exhibit a wider range of antigen peptide-MHC recognition, which can detect more tumor mutation antigens. In our earlier studies, a nitrated CD4+ T-cell epitope (NitraTh) was constructed as a novel CD4+ T-cell epitope that can enhance the immunogenicity of multiple tumor antigens. Therefore, we designed vaccines targeting MHC-II neoantigen epitopes using the nitrated T-cell epitope containing immunogenic amino acids. We found that vaccines conjugated with NitraTh exhibited enhanced immunogenicity. Crucially, the NitraTh-modified MHC-II tumor neoantigen vaccines increased the proportion of CD4+ T cells that infiltrate tumors and the spleen, elevated the expression of several cytokines with antitumor effects and facilitated the transformation of CD4+ T cells into Th1 cells, thereby reducing tumor growth. Additionally, the nitrated epitope has been shown to transform naïve CD4+ T cells into effector memory cells, thus facilitating enduring antitumor actions. The strategy of combining nitrated epitopes with MHC-II neoantigen epitopes confirms the significance of CD4+ T-cell immunity in cancer and may provide a novel approach for cancer vaccine design. SIGNIFICANCE STATEMENT: This study presents a novel design paradigm for tumor vaccines-combining MHC-II epitopes with nitrated CD4+ T-cell epitopes. This approach promotes the differentiation of CD4+ T cells toward a Th1 phenotype and generates long-lasting effector memory CD4+ T cells. Under the enhanced effects of CD4+ T cells, the vaccines we designed achieved superior antitumor efficacy and improved the immunosuppressive tumor microenvironment.

Synergistic action of combining photodynamic therapy with immunotherapy for eradicating solid tumors in animal models: A systematic review

Malignancies maintain a high rate of mortality worldwide each year, requiring the development of novel therapeutic platforms. Immunotherapy approaches are considered a revolutionary treatment for overcoming malignancies. Photodynamic therapy (PDT) has attracted significant attention in various cancer types. Recent progress in cancer therapies has underscored the potential of combining PDT with immunotherapy. This approach can improve therapeutic outcomes by directly eliminating tumor cells and boosting immune responses for sustained anti-tumor effects in the whole body. This study aims to determine the relative efficacy of combining PDT with immunotherapy compared to PDT alone. Following the PRISMA guidance, an extensive literature review was conducted utilizing Scopus, Web of Science, and PubMed to identify high-quality preclinical studies exploring various aspects of PDT combined with immunotherapy. The adopted PICO framework included studies with rigorous experimental designs and relevant outcomes. The present review reveals the characteristics of tumor models, delivery systems, photosensitizers, and immunotherapy approaches. Key findings indicate that the combined PDT-immunotherapy approach shows promise in treating multiple tumors according to their size, therapeutic biomarkers, and inhibition of distant tumors. Finally, this integrated therapeutic strategy holds significant promise for advancing cancer treatment paradigms by potentiating each treatment efficacy; however, its clinical utility requires careful consideration of the associated challenges.

Navigating established and emerging biomarkers for immune checkpoint inhibitor therapy

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

Radiotherapy-immunity lncRNA model predicts lung adenocarcinoma prognosis and treatment outcome and distinguishes between hot and cold tumors

BACKGROUND

There are many prognostic markers for lung adenocarcinoma (LUAD). However, studies on the prognosis of LUAD by radiotherapy immune-related long noncoding RNAs (lncRNAs) are extremely rare.

METHODS

We have compiled 1121 radiotherapy susceptibility differential genes and 6195 immune-related genes. After that, we screened radiotherapy-immunity lncRNAs associated with proliferation by co-expression, univariate, least absolute shrinkage selection operator regression (LASSO), and multivariate analysis of variance. Finally, we constructed a prognostic model based on 6 lncRNAs, and verified the accuracy of the predictive model by ROC and C index. In addition, we used the constructed scoring model to analyze the model's association with the characteristics of immune cell infiltration, immune checkpoint and drug sensitivity. Finally, the whole sample was divided into 2 clusters to further distinguish hot and cold tumors.

RESULTS

We constructed a risk score model built on 6 prognostically relevant lncRNAs. Patients were categorized into high-risk and low-risk patients based on median scores in the Train group. We found that people in the high-risk group had a lower survival rate than those in the low-risk group. However, those in the high-risk group were more sensitive to chemotherapy, targeted drugs and also more sensitive to immunotherapy drugs. Based on the line graphs of T, N, Age, Stage and Risk, the corresponding scores can be summed up to visualize the survival rate of patients at 1, 3 and 5 years. Gene set enrichment analysis (GSEA) suggested that radiotherapy-immunity-related lncRNA might be related to pathways such as cell cycle, T cell receptor signaling pathway. It is noteworthy that in our study, cluster 1 was considered to be a hot tumor more sensitive to immunotherapy.

CONCLUSION

In summary, we constructed a risk score model built on six radiosensitivity and immune-related lncRNAs, which is expected to be a potential predictive biomarker for radiosensitivity and LUAD prognosis.

5-Methylcytosine methylation predicts cervical cancer prognosis, shaping immune cell infiltration

BackgroundEpigenetics, encompassing DNA and RNA modifications, has emerged as a prominent area of research in the post-genomic era. Numerous studies have elucidated the impact of epigenetics on tumor regulation. However, the methylation patterns of 5-methylcytosine in cervical cancer as well as its role in the tumor microenvironment and immunotherapy remain poorly understood.MethodsUtilizing a comprehensive dataset encompassing samples from 306 patients with cervical cancer from The Cancer Genome Atlas and Gene Expression Omnibus repositories, we conducted an in-depth analysis to evaluate the potential association between the modification patterns of 5-methylcytosine and the infiltration of cells within the tumor microenvironment, taking into account 11 regulators of 5-methylcytosine modification. Subsequently, we employed stepwise regression and Least Absolute Shrinkage and Selection Operator Cox regression to quantify 5-methylcytosine modification patterns in patients with cervical squamous cell carcinoma and endocervical adenocarcinoma, yielding the 5-methylcytosine score. Our study explored the link between the 5-methylcytosine score and clinical characteristics as well as prognostic outcomes in patients with cervical squamous cell carcinoma and endocervical adenocarcinoma.ResultsA comprehensive analysis of 306 patients with cervical cancer revealed two distinct 5-methylcytosine modification patterns, henceforth labeled as 5-methylcytosine clusters A and B. These clusters exhibited distinct immunological profiles and biological attributes, with 5-methylcytosine cluster A exhibiting a higher degree of immune cell infiltration. Utilizing univariate Cox regression analysis, we identified 367 genes regulated by 5-methylcytosine that were significantly correlated with patient prognosis. This analysis further stratified the samples into three distinct genomic subtypes. Survival analyses indicated that patients belonging to gene cluster C exhibited more favorable survival outcomes than those belonging to gene clusters A and B. Intriguingly, most 5-methylcytosine regulatory factors had higher expression levels in gene cluster B than in gene cluster A. Gene set enrichment analysis of a single sample revealed elevated immune cell infiltration within gene cluster B, indicating a stronger immune response in this cluster. The 5-methylcytosine score feature was utilized to determine the 5-methylcytosine modification pattern in cervical cancer, revealing that patients with low 5-methylcytosine scores exhibited better survival rates, whereas those with high scores had increased mutation frequencies and better treatment responses.ConclusionsThis research underscores the key role of 5-methylcytosine modification patterns in cervical cancer. Analysis of these patterns will deepen our understanding of the cervical cancer tumor microenvironment, paving the way for the development of more refined and effective immunotherapy strategies.

Emerging roles of hyaluronic acid hydrogels in cancer treatment and wound healing: A review

Hyaluronic acid (HA)-derived hydrogels demonstrate a significant development in the biomedical uses, especially in cancer treatment and wound repair. Cancer continues to be one of the leading causes of death worldwide, with current therapies frequently impeded by lack of specificity, side effects, and the emergence of resistance. HA hydrogels, characterized by their distinctive three-dimensional structure, hydrophilic nature, and biocompatibility, develop an advanced platform for precise drug delivery, improving therapeutic results while minimizing systemic toxicity. These hydrogels facilitate the controlled release of drugs, genes, and various therapeutic substances, enhancing the effectiveness of chemotherapy, radiotherapy, and immunotherapy. Additionally, they can be designed to react to stimuli such as pH, light, and magnetic fields, enhancing their therapeutic capabilities. In the process of wound healing, the hydrophilic and porous characteristics of HA hydrogels establish a moist environment encouraging cell growth and contributes to the tissue recovery. By imitating the extracellular matrix, they promote tissue regeneration, improve angiogenesis, and influence immune reactions. This review examines the various functions of HA-based hydrogels in cancer treatment and wound healing, highlighting their advancement, applications, and ability to change existing therapeutic methods in these important health sectors.

Immunomodulation on tumor immune microenvironment in acquired targeted therapy resistance and implication for immunotherapy resistance

The emergence of molecularly targeted therapies and immunotherapies has revolutionized cancer treatment, yet the optimal sequencing of these modalities remains debated. While targeted therapies often induce initial immunostimulatory effects, the development of resistance is accompanied by dynamic alterations in the tumor-immune microenvironment. These changes can promote tumor growth, hinder immune surveillance, and contribute to subsequent immunotherapy resistance. This review focuses on solid tumors and summarizes the immunomodulatory effects arising in the context of targeted therapy resistance, highlighting the challenges they pose for the subsequent immunotherapy efficacy.

Synergistic Strategies for Lung Cancer Immunotherapy: Combining Phytochemicals and Immune-Checkpoint Inhibitors

Lung cancer remains one of the most widespread and deadliest malignant tumors globally, with a particularly high mortality rate among all cancers. Recently, immunotherapy, particularly immune checkpoint inhibitors (ICIs), has emerged as a crucial treatment strategy for lung cancer patients, following surgical intervention, radiotherapy, chemotherapy, and targeted drug therapies. However, the therapeutic limitations are caused owing to their low response rate and undesirable side effects such as immune-related pneumonitis. Therefore, developing new strategies to improve the efficacy of ICIs while minimizing immune-related adverse events will be crucial for cancer immunotherapy. The tumor immune microenvironment plays a significant role in the success of lung cancer immunotherapy, and the immunosuppressive characteristics of the immune microenvironment are one of the major obstacles to the poor immunotherapeutic effect. Phytochemicals, naturally occurring compounds in plants, have shown promise in enhancing cancer immunotherapy by remodeling the immunosuppressive microenvironment, offering the potential to increase the efficacy of ICIs. Therefore, this review summarizes the associated mechanisms of phytochemicals remodeling the immunosuppressive microenvironment in lung cancer. Additionally, the review will focus on the synergistic effects of combining phytochemicals with ICIs, aiming to improve anticancer efficacy and reduce side effects, which may hopefully offer novel strategies to overcome current limitations in immunotherapy.

Ezetimibe mediated RPS6KA2 inhibits colorectal cancer proliferation via PCSK9/MAPK signaling pathway

To investigate the effect and molecular mechanism of ezetimibe on colorectal cancer (CRC), our study found that ezetimibe significantly inhibited the proliferation and progression of CRC. Further study showed that RPS6KA2 might be the target gene of ezetimibe treatment on CRC. RPS6KA2 expression was significantly lower in human CRC tissue samples and associated with T classification and vascular invasion of tumor cells. RPS6KA2 inhibited proliferation, migration, and invasion of CRC cells. The underlying mechanisms indicated that interaction between RPS6KA2 and PCSK9 was observed within the cytoplasmic compartment of CRC cells. RPS6KA2 suppressed PCSK9 and MAPK signaling pathway in CRC cells. BI-D1780 which is an inhibitor of RPS6KA2 increased PCSK9 and MAPK signaling pathway related proteins expression in SW620 cells. However, an inhibitor or stimulator of MAPK did not affect RPS6KA2 and PCSK9 expression, respectively. In vivo, CRC cells with RPS6KA2 or PCSK9 overexpression could inhibit or promote tumor growth and metastasis, respectively. PCSK9 promoted proliferation, migration, and invasion of CRC cells. PCSK9 expression was higher in human CRC samples and associated with N classification and TNM stage of CRC. In conclusion, our study firstly suggests that ezetimibe suppresses CRC progression by upregulating RPS6KA2 while downregulating PCSK9/MAPK signaling pathway.

T-cell receptors identified by a personalized antigen-agnostic screening approach target shared neoantigen KRAS Q61H

Adoptive cell therapy (ACT) with TCR-engineered T-cells represents a promising alternative to TIL- or CAR-T therapies for patients with advanced solid cancers. Currently, selection of therapeutic TCRs critically depends on knowing the target antigens, a condition excluding most patients from treatment. Direct antigen-agnostic identification of tumor-specific T-cell clonotypes and TCR-T manufacturing using their TCRs can advance ACT for patients with aggressive solid cancers. We present a method to identify tumor-specific clonotypes from surgical specimens by comparing TCRβ-chain repertoires of TILs and adjacent tissue-resident lymphocytes. In six out of seven NSCLC-patients analyzed, our selection of tumor-specific clonotypes based on TIL-abundance and high tumor-to-nontumor frequency ratios was confirmed by gene expression signatures determined by scRNA-Seq. In three patients, we demonstrated that predicted tumor-specific clonotypes reacted against autologous tumors. For one of these patients, we engineered TCR-T cells with four candidate tumor-specific TCRs that showed reactivity against the patient's tumor and HLA-matched NSCLC cell lines. The TCR-T cells were then used to screen for candidate neoantigens and aberrantly expressed antigens. Three TCRs recognized recurrent driver-mutation KRAS Q61H-peptide ILDTAGHEEY presented by HLA-A*01:01. The TCRs were also dominant in a tumor relapse, one was found in cell free DNA. The finding of homologous TCRs in independent KRAS Q61H-positive cancers suggests a therapeutic opportunity for HLA-matched patients with KRAS Q61H-expressing tumors.

Advances in Studying Cancer Immunology in Mice

The recent rise in effective immuno-oncology therapies has increased demand for experimental approaches to model anticancer immunity. A variety of mouse models have been developed and used to study cancer immunology. These include mutagen-induced, genetically engineered, syngeneic, and other models of cancer immunology. These models each have the potential to define mechanistic aspects of anticancer immune responses, identify potential therapeutic targets, and serve as preclinical models for further therapeutic development. Specific benefits and liabilities are characteristic of particular cancer immunology modeling approaches. The optimal choice and utilization of models depends on the cancer immunology scientific question being addressed and can serve to increase mechanistic understanding and development of human immuno-oncology therapies.

Individualized Neoantigen-Directed Melanoma Therapy

Individualized neoantigen-directed therapy represents a groundbreaking approach in melanoma treatment that leverages the patient's own immune system to target cancer cells. This innovative strategy involves the identification of unique immunogenic neoantigens (mutated proteins specific to an individual's tumor) and the development of therapeutic vaccines that either consist of peptide sequences or RNA encoding these neoantigens. The goal of these therapies is to induce neoantigen-specific immune responses, enabling the immune system to recognize and destroy cancer cells presenting the targeted neoantigens. This individualized approach is particularly advantageous given the genetic heterogeneity of melanoma, which exhibits distinct mutations among different patients. In contrast to traditional therapies, neoantigen-directed therapy offers a tailored treatment that potentially reduces off-target side effects and enhances therapeutic efficacy. Recent advances in neoantigen prediction and vaccine development have facilitated clinical trials exploring the combination of neoantigen vaccines with immune checkpoint inhibitors. These trials have shown promising clinical outcomes, underscoring the potential of this personalized approach. This review provides an overview of the rationale behind neoantigen-directed therapies and summarizes the current state of knowledge regarding personalized neoantigen vaccines in melanoma treatment.

Regulation of PD-L1 glycosylation and advances in cancer immunotherapy

Protein glycosylation plays a versatile role in regulating homeostasis, such as cell migration, protein sorting, and the immune response. Drugs aimed at targeting glycosylation have strong implications for immunity enhancement, diagnosis, and cancer regression. Programmed death-ligand 1 (PD-L1), expressed in cancer or antigen-presenting cells, binds to programmed cell death protein 1 (PD-1) and suppresses T cells. Glycosylation of PD-L1 at N35, N192, N200, and N219 stabilizes PD-L1 on the cancer cell surface, which contributes to immune evasion by inhibiting T cell activity. To date, at least six glycosyltransferases and four associate proteins are known to regulate PD-L1 glycosylation. Terminal modifications such as poly-N-acetyl-lactosamine (poly-LacNAC), sulfation, and sialylation are commonly found on PD-L1, acting as an immune recognition ligand and regulating certain immune responses. Studies have identified many mechanisms and potential therapeutic targets within the glycosylation pathways of PD-L1, revealing their involvement in cancer pathology, immune evasion, and resistance to immunotherapy. In this review, we covered the glycoforms, terminal moiety, binding lectin, glycosyltransferase, as well as sugar analogs focusing on glycosylated PD-L1. We present a mechanism that originates from the endoplasmic reticulum (ER)-Golgi apparatus (Golgi) and its subsequent translocation to the cell membrane. This pathway determines the immune suppression function of PD-L1 and therefore regulates the immune response such as T cells, monocytes, and macrophages. This collection of findings underscores the significance of glycosylation in the role of PD-L1 in cancer and highlights multiple potential targets and strategies for improving therapeutic intervention and diagnostic techniques.

Antigen-presenting fibroblasts: emerging players in immune modulation and therapeutic targets

Antigen-presenting fibroblasts are a newly recognized subset that challenges the traditional view of these cells as mere structural components. Under pathological or environmental stimuli, fibroblasts acquire antigen-presenting capabilities through the expression of MHC-II molecules and co-stimulatory factors, enabling them to interact with T cells and modulate immune responses. These specialized fibroblasts have been identified across various tissues and diseases, where they play context-dependent roles, either amplifying immune dysregulation or contributing to immune homeostasis. This review synthesizes recent advances in understanding the origins, activation, and functions of antigen-presenting fibroblasts. It highlights their role in promoting pathogenic immune responses and offering therapeutic opportunities through targeted modulation. Advancing our understanding of antigen-presenting fibroblasts holds great promise for developing innovative approaches to immune modulation and therapy across a range of diseases.

Deep learning-based prediction of autoimmune diseases

Autoimmune Diseases are a complex group of diseases caused by the immune system mistakenly attacking body tissues. Their etiology involves multiple factors such as genetics, environmental factors, and abnormalities in immune cells, making prediction and treatment challenging. T cells, as a core component of the immune system, play a critical role in the human immune system and have a significant impact on the pathogenesis of autoimmune diseases. Several studies have demonstrated that T-cell receptors (TCRs) may be involved in the pathogenesis of various autoimmune diseases, which provides strong theoretical support and new therapeutic targets for the prediction and treatment of autoimmune diseases. This study focuses on the prediction of several autoimmune diseases mediated by T cells, and proposes two models: one is the AutoY model based on convolutional neural networks, and the other is the LSTMY model, a bidirectional LSTM network model that integrates the attention mechanism. Experimental results show that both models exhibit good performance in the prediction of the four autoimmune diseases, with the AutoY model performing slightly better in comparison. In particular, the average area under the ROC curve (AUC) of the AutoY model exceeded 0.93 in the prediction of all the diseases, and the AUC value reached 0.99 in two diseases, type 1 diabetes and multiple sclerosis. These results demonstrate the high accuracy, stability, and good generalization ability of the two models, which makes them promising tools in the field of autoimmune disease prediction and provides support for the use of the TCR bank for the noninvasive detection of autoimmune disease non-invasive detection is supported.

Identification and Phenotypic Characterization of Neoantigen-Specific Cytotoxic CD4+ T Cells in Endometrial Cancer

Tumor-reactive CD4+ T cells often accumulate in the tumor microenvironment (TME) in human cancer, but their functions and roles in antitumor responses remain elusive. Here, we investigated the immunopeptidome of HLA class II-positive (HLA-II+) endometrial cancer with an inflamed TME using a proteogenomic approach. We identified HLA-II neoantigens, one of which induced polyclonal CD4+ tumor-infiltrating lymphocyte responses. We then experimentally demonstrated that neoantigen-specific CD4+ tumor-infiltrating lymphocytes lyse target cells in an HLA-II-dependent manner. Single-cell transcriptomic analysis of the TME coupled with T-cell receptor sequencing revealed the presence of CD4+ T-cell clusters characterized by CXCL13 expression. The CXCL13+ clusters contained two subclusters with distinct cytotoxic gene expression patterns. The identified neoantigen-specific CD4+ T cells were found exclusively in one of the CXCL13+ subclusters characterized by granzyme B and CCL5 expression. These results demonstrate the involvement of tumor-reactive CD4+ T cells with cytotoxic function in immune surveillance of endometrial cancer and reveal their transcriptomic signature.

Discovery of tumor-reactive T cell receptors by massively parallel library synthesis and screening

T cell receptor (TCR) gene therapy is a potent form of cellular immunotherapy in which patient T cells are genetically engineered to express TCRs with defined tumor reactivity. However, the isolation of therapeutic TCRs is complicated by both the general scarcity of tumor-specific T cells among patient T cell repertoires and the patient-specific nature of T cell epitopes expressed on tumors. Here we describe a high-throughput, personalized TCR discovery pipeline that enables the assembly of complex synthetic TCR libraries in a one-pot reaction, followed by pooled expression in reporter T cells and functional genetic screening against patient-derived tumor or antigen-presenting cells. We applied the method to screen thousands of tumor-infiltrating lymphocyte (TIL)-derived TCRs from multiple patients and identified dozens of CD4+ and CD8+ T-cell-derived TCRs with potent tumor reactivity, including TCRs that recognized patient-specific neoantigens.

Low-avidity T cells drive endogenous tumor immunity in mice and humans

T cells recognize neoepitope peptide-major histocompatibility complex class I on cancer cells. The strength (or avidity) of the T cell receptor-peptide-major histocompatibility complex class I interaction is a critical variable in immune control of cancers. Here, we analyze neoepitope-specific CD8 cells of distinct avidities and show that low-avidity T cells are the sole mediators of cancer control in mice and are solely responsive to checkpoint blockade in mice and humans. High-avidity T cells are ineffective and immune-suppressive. The mechanistic basis of these differences lies in the higher exhaustion status of high-avidity cells. High-avidity T cells have a distinct transcriptomic profile that is used here to calculate an 'avidity score', which we then use for in silico identification of low-avidity and high-avidity T cells in mice and humans. Surprisingly, CD8+ T cells with identical T cell receptors exhibit wide variation in avidities, suggesting an additional level of regulation of T cell activity. Aside from providing a better understanding of endogenous T cell responses to cancer, these findings might instruct future immunotherapy strategies.

Pembrolizumab in microsatellite-instability-high and mismatch-repair-deficient advanced solid tumors: updated results of the KEYNOTE-158 trial

The phase 2 trial KEYNOTE-158 ( NCT02628067 ) evaluated pembrolizumab in microsatellite-instability-high and mismatch-repair-deficient (MSI-H/dMMR) noncolorectal tumors. With 373 participants (95% with baseline MSI/dMMR documentation) and 4.5 years of follow-up, the primary endpoint of overall response rate was 33.8%. Secondary endpoints of duration of response, overall survival and progression-free survival were 63.2, 19.8 and 4.0 months, respectively. Grade ≥3 treatment-related adverse events occurred in 50 (13%) participants. These results further support pembrolizumab use in MSI-H/dMMR tumors.

Loss of tumor cell MHC Class II drives insensitivity of BRAF-mutant anaplastic thyroid cancers to MAPK inhibitors

Cancer cells present neoantigens dominantly through MHC class I (MHCI) to drive tumor rejection through cytotoxic CD8+ T-cells. There is growing recognition that a subset of tumors express MHC class II (MHCII), causing recognition of antigens by TCRs of CD4+ T-cells that contribute to the anti-tumor response. We find that mouse Braf V600E -driven anaplastic thyroid cancers (ATC) respond markedly to the RAF + MEK inhibitors dabrafenib and trametinib (dab/tram) and that this is associated with upregulation of MhcII in cancer cells and increased CD4+ T-cell infiltration. A subset of recurrent tumors lose MhcII expression due to silencing of Ciita , the master transcriptional regulator of MhcII, despite preserved interferon gamma signal transduction, which can be rescued by EZH2 inhibition. Orthotopically-implanted Ciita -/- and H2-Ab1 -/- ATC cells into immune competent mice become unresponsive to the MAPK inhibitors. Moreover, depletion of CD4+, but not CD8+ T-cells, also abrogates response to dab/tram. These findings implicate MHCII-driven CD4+ T cell activation as a key determinant of the response of Braf-mutant ATCs to MAPK inhibition.

Centrosome protein TAX1BP2 mediates STING-dependent immune response and potentiates anti-PD-1 efficacy in hepatocellular carcinoma

Centrosome aberrations are a common feature in human cancer cells. Our previous studies demonstrated that the centrosomal protein Tax1 binding protein 2 (TAX1BP2) inhibits centrosome overduplication and is underexpressed in hepatocellular carcinoma (HCC). Here, we report that Intratumoral TAX1BP2 promotes tumor lymphocyte infiltration and enhances the efficacy of anti-PD-1 therapy. Clinically, we discovered that a hallmark of low TAX1BP2 expression in HCC tumors is T cell exclusion, whereas re-depression of TAX1BP2 in preclinical models restores antitumor immunity and potentiates anti-PD-1 efficacy. Mechanistically, we identified that reconstitution of intratumor TAX1BP2 triggers the type I interferon (IFN-I) response and subsequent facilitation of a subtype of CD27+CD8+ T cell recruitment. Furthermore, we demonstrated that Intratumor TAX1BP2 upregulates STING by inhibiting the hyperactivation of DNMT1, and EZH2 is linked to endogenous LKB1 activity.

Hypoxia is linked to acquired resistance to immune checkpoint inhibitors in lung cancer

Despite the established use of immune checkpoint inhibitors (ICIs) to treat non-small cell lung cancer (NSCLC), only a subset of patients benefit from treatment and ∼50% of patients whose tumors respond eventually develop acquired resistance (AR). To identify novel drivers of AR, we generated murine Msh2 knock-out (KO) lung tumors that initially responded but eventually developed AR to anti-PD-1, alone or in combination with anti-CTLA-4. Resistant tumors harbored decreased infiltrating T cells and reduced cancer cell-intrinsic MHC-I and MHC-II levels, yet remained responsive to IFNγ. Resistant tumors contained extensive regions of hypoxia, and a hypoxia signature derived from single-cell transcriptional profiling of resistant cancer cells was associated with decreased progression-free survival in a cohort of NSCLC patients treated with anti-PD-1/PD-L1 therapy. Targeting hypoxic tumor regions using a hypoxia-activated pro-drug delayed AR to ICIs in murine Msh2 KO tumors. Thus, this work provides a rationale for targeting tumor metabolic features, such as hypoxia, in combination with immune checkpoint inhibition.

Tumor immunology and immunotherapy for endometrial cancer

INTRODUCTION

Recent clinical trials show the efficacy of immune checkpoint inhibitors (ICIs) or a combination of ICI and poly (ADP-ribose) polymerase (PARP) inhibitors for advanced or recurrent endometrial cancer. However, the basis for such treatment effects remains unclear, hindering the advancement of personalized therapy.

AREAS COVERED

This review includes a detailed interpretation of subgroup analysis data from phase III clinical trials for endometrial cancer evaluating the efficacy of chemotherapy plus ICIs (NRG-GY018, RUBY, AtTEnd, KEYNOTE-B21) or chemotherapy plus ICI with/without olaparib (DUO-E). We focused on the relationship between obesity, the effect of PARP inhibitors, and tumor immunity in endometrial cancer, searched for relevant literature published from 2000 to 2024 in PubMed, and conducted a narrative review.

EXPERT OPINION

Chemotherapy plus ICI is appropriate for dMMR. Chemotherapy plus ICI and PARP inhibitor may be appropriate for TP53abn type or serous carcinoma because PARP inhibitor enhances the efficacy of ICI by activating the cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS)-stimulator of interferon genes (STING) pathway. Obese patients may benefit more from ICIs, and this appears to cause the variation in efficacy between regions/countries. Administration for measurable disease appears important to increase the effect of ICIs. Diet and exercise may also be important factors.

Acquired resistance to PD-L1 inhibition enhances a type I IFN-regulated secretory program in tumors

Therapeutic inhibition of programmed cell death ligand (PD-L1) is linked to alterations in interferon (IFN) signaling. Since IFN-regulated intracellular signaling can control extracellular secretory programs in tumors to modulate immunity, we examined IFN-related secretory changes in tumor cells following resistance to PD-L1 inhibition. Here we report an anti-PD-L1 treatment-induced secretome (PTIS) in tumor models of acquired resistance that is regulated by type I IFNs. These secretory changes can suppress activation of T cells ex vivo while diminishing tumor cell cytotoxicity, revealing that tumor-intrinsic treatment adaptations can exert broad tumor-extrinsic effects. When reimplanted in vivo, resistant tumor growth can slow or stop when PTIS components are disrupted individually, or when type I IFN signaling machinery is blocked. Interestingly, genetic and therapeutic disruption of PD-L1 in vitro can only partially recapitulate the PTIS phenotype highlighting the importance of developing in vivo-based resistance models to more faithfully mimic clinically-relevant treatment failure. Together, this study shows acquired resistance to immune-checkpoint inhibitors 'rewires' tumor secretory programs controlled by type I IFNs that, in turn, can protect from immune cell attack.

Efficient Predictor for Immunotherapy Efficacy: Detecting Pan-Clones Effector Tumor Antigen-Specific T Cells in Blood by Nanoparticles Loading Whole Tumor Antigens

Cancer involves tumor cells and tumor-specific immunity. The ability to accurately quantify tumor-specific immunity is limited. Most immunotherapies function by activating new effector tumor antigen-specific T cells (ETASTs) or reactivating the pre-existing ETASTs repertoire. Therefore, the amount of ETASTs can be used to characterize immunotherapy efficacy. Tumor antigens are highly heterogeneous and detecting most ETASTs is challenging. Therefore, nanoparticles loading whole-cell tumor antigens are used to activate and detect pan-clones ETASTs in the blood. The differences between ETASTs and other T cells are transformed into activated and non-activated states. By measuring markers of the activated status and cytotoxic function of ETASTs, it can distinguish ETASTs from other T cells. ETASTs in patients with lung cancer are higher than those in healthy individuals and those with benign pulmonary nodules. Therapeutic efficacy positively correlated with the number of ETASTs in the blood. ETATS levels increase only in the blood of patients who respond to immunotherapy. Single-cell sequencing studies validated these findings. This study provides a highly accurate, specific, non-invasive, and efficient biomarker for predicting immunotherapy efficacy in lung and other cancers. This method can also be applied to evaluate the efficacy of other treatments, such as radiotherapy, oncolytic viruses, and nanomedicine-based therapies.

Establishment of a novel tumor neoantigen prediction tool for personalized vaccine design

The personalized neoantigen nanovaccine (PNVAC) platform for patients with gastric cancer we established previously exhibited promising anti-tumor immunoreaction. However, limited by the ability of traditional neoantigen prediction tools, a portion of epitopes failed to induce specific immune response. In order to filter out more neoantigens to optimize our PNVAC platform, we develop a novel neoantigen prediction model, NUCC. This prediction tool trained through a deep learning approach exhibits better neoantigen prediction performance than other prediction tools, not only in two independent epitope datasets, but also in a totally new epitope dataset we construct from scratch, including 25 patients with advance gastric cancer and 150 candidate mutant peptides, 13 of which prove to be neoantigen by immunogenicity test in vitro. Our work lay the foundation for the improvement of our PNVAC platform for gastric cancer in the future.

Relevance of mutation-derived neoantigens and non-classical antigens for anticancer therapies

Efficacy of cancer immunotherapies relies on correct recognition of tumor antigens by lymphocytes, eliciting thus functional responses capable of eliminating tumor cells. Therefore, important efforts have been carried out in antigen identification, with the aim of understanding mechanisms of response to immunotherapy and to design safer and more efficient strategies. In addition to classical tumor-associated antigens identified during the last decades, implementation of next-generation sequencing methodologies is enabling the identification of neoantigens (neoAgs) arising from mutations, leading to the development of new neoAg-directed therapies. Moreover, there are numerous non-classical tumor antigens originated from other sources and identified by new methodologies. Here, we review the relevance of neoAgs in different immunotherapies and the results obtained by applying neoAg-based strategies. In addition, the different types of non-classical tumor antigens and the best approaches for their identification are described. This will help to increase the spectrum of targetable molecules useful in cancer immunotherapies.

Recent progress in mRNA cancer vaccines

The research and development of messenger RNA (mRNA) cancer vaccines have gradually overcome numerous challenges through the application of personalized cancer antigens, structural optimization of mRNA, and the development of alternative RNA-based vectors and efficient targeted delivery vectors. Clinical trials are currently underway for various cancer vaccines that encode tumor-associated antigens (TAAs), tumor-specific antigens (TSAs), or immunomodulators. In this paper, we summarize the optimization of mRNA and the emergence of RNA-based expression vectors in cancer vaccines. We begin by reviewing the advancement and utilization of state-of-the-art targeted lipid nanoparticles (LNPs), followed by presenting the primary classifications and clinical applications of mRNA cancer vaccines. Collectively, mRNA vaccines are emerging as a central focus in cancer immunotherapy, offering the potential to address multiple challenges in cancer treatment, either as standalone therapies or in combination with current cancer treatments.

Towards designing improved cancer immunotherapy targets with a peptide-MHC-I presentation model, HLApollo

Based on the success of cancer immunotherapy, personalized cancer vaccines have emerged as a leading oncology treatment. Antigen presentation on MHC class I (MHC-I) is crucial for the adaptive immune response to cancer cells, necessitating highly predictive computational methods to model this phenomenon. Here, we introduce HLApollo, a transformer-based model for peptide-MHC-I (pMHC-I) presentation prediction, leveraging the language of peptides, MHC, and source proteins. HLApollo provides end-to-end treatment of MHC-I sequences and deconvolution of multi-allelic data, using a negative-set switching strategy to mitigate misassigned negatives in unlabelled ligandome data. HLApollo shows a 12.65% increase in average precision (AP) on ligandome data and a 4.1% AP increase on immunogenicity test data compared to next-best models. Incorporating protein features from protein language models yields further gains and reduces the need for gene expression measurements. Guided by clinical use, we demonstrate pan-allelic generalization which effectively captures rare alleles in underrepresented ancestries.

Cytokine-armed pyroptosis induces antitumor immunity against diverse types of tumors

Inflammasomes are defense complexes that utilize cytokines and immunogenic cell death (ICD) to stimulate the immune system against pathogens. Inspired by their dual action, we present cytokine-armed pyroptosis as a strategy for boosting immune response against diverse types of tumors. To induce pyroptosis, we utilize designed tightly regulated gasdermin D variants comprising different pore-forming capabilities and diverse modes of activation, representing a toolbox of ICD inducers. We demonstrate that the electrogenic transfer of ICD effector-encoding plasmids into mouse melanoma tumors when combined with intratumoral expression of cytokines IL-1β, IL-12, or IL-18, enhanced anti-tumor immune responses. Careful selection of immunostimulatory molecules is, however, imperative as a combination of IL-1β and IL-18 antagonized the protective effect of pyroptosis by IFNγ-mediated upregulation of several immunosuppressive pathways. Additionally, we show that the intratumoral introduction of armed pyroptosis provides protection against distant tumors and proves effective across various tumor types without inducing systemic inflammation. Deconstructed inflammasomes thus serve as a powerful, tunable, and tumor-agnostic strategy to enhance antitumor response, even against the most resilient types of tumors.

Single-cell and spatial transcriptomics reveal SPP1-CD44 signaling drives primary resistance to immune checkpoint inhibitors in RCC

BACKGROUND

Immune checkpoint inhibitors (ICIs) are a cornerstone therapy for advanced renal cell carcinoma (RCC). However, significant rates of primary resistance hinder their efficacy, and the underlying mechanisms remain poorly understood. This study aims to unravel the tumor-immune interactions and signaling pathways driving primary resistance to ICIs in RCC.

METHODS

We integrated single-cell RNA sequencing, spatial transcriptomics, and clinical sample analysis to investigate the tumor microenvironment and intercellular signaling. Advanced computational methods, including cell-cell communication networks, pseudotime trajectories, and gene set enrichment analysis (GSEA), were employed to uncover the underlying resistance mechanisms.

RESULTS

Compared to the sensitive group, the primary resistance group exhibited a significant increase in SPP1-CD44 signaling-mediated interactions between tumor cells and immune cells. These interactions disrupted antigen presentation in immune effector cells and suppressed key chemokine and cytokine pathways, thereby impairing effective immune responses. In contrast, the sensitive group showed more active antigen presentation and cytokine signaling, which facilitated stronger immune responses. Furthermore, the interaction between SPP1-secreting tumor cells and CD44-expressing exhausted CD8 + T cells activated the MAPK signaling pathway within CD8 + Tex cells, exacerbating T cell exhaustion and driving the development of ICI resistance in RCC.

CONCLUSION

Our findings reveal a potential mechanism by which SPP1-CD44 signaling mediates tumor-immune cell interactions leading to ICI resistance, providing a theoretical basis for targeting and disrupting this signaling to overcome primary resistance in RCC.

Granulomatous inflammatory responses are elicited in the liver of PD-1 knockout mice by de novo genome mutagenesis

Introduction

Programmed death-1 (PD-1) is a negative regulator of immune responses. Upon deletion of PD-1 in mice, symptoms of autoimmunity developed only after they got old. In a model experiment in cancer immunotherapy, PD-1 was shown to prevent cytotoxic T lymphocytes from attacking cancer cells that expressed neoantigens derived from genome mutations. Furthermore, the larger number of genome mutations in cancer cells led to more robust anti-tumor immune responses after the PD-1 blockade. To understand the common molecular mechanisms underlying these findings, we hypothesize that we might have acquired PD-1 during evolution to avoid/suppress autoimmune reactions against neoantigens derived from mutations in the genome of aged individuals.

Methods

To test the hypothesis, we introduced random mutations into the genome of young PD-1-/- and PD-1+/+ mice. We employed two different procedures of random mutagenesis: administration of a potent chemical mutagen N-ethyl-N-nitrosourea (ENU) into the peritoneal cavity of mice and deletion of MSH2, which is essential for the mismatch-repair activity in the nucleus and therefore for the suppression of accumulation of random mutations in the genome.

Results

We observed granulomatous inflammatory changes in the liver of the ENU-treated PD-1 knockout (KO) mice but not in the wild-type (WT) counterparts. Such lesions also developed in the PD-1/MSH2 double KO mice but not in the MSH2 single KO mice.

Conclusion

These results support our hypothesis about the physiological function of PD-1 and address the mechanistic reasons for immune-related adverse events observed in cancer patients having PD-1-blockade immunotherapies.

Biomarkers for immunotherapy resistance in non-small cell lung cancer

Immunotherapy has revolutionised the treatment landscape of non-small cell lung cancer (NSCLC), significantly improving survival outcomes and offering renewed hope to patients with advanced disease. However, the majority of patients experience limited long-term benefits from immune checkpoint inhibition (ICI) due to the development of primary or acquired immunotherapy resistance. Accurate predictive biomarkers for immunotherapy resistance are essential for individualising treatment strategies, improving survival outcomes, and minimising potential treatment-related harm. This review discusses the mechanisms underlying resistance to immunotherapy, addressing both cancer cell-intrinsic and cancer cell-extrinsic resistance processes. We summarise the current utility and limitations of two clinically established biomarkers: programmed death ligand 1 (PD-L1) expression and tumour mutational burden (TMB). Following this, we present a comprehensive review of emerging immunotherapy biomarkers in NSCLC, including tumour neoantigens, epigenetic signatures, markers of the tumour microenvironment (TME), genomic alterations, host-microbiome composition, and circulating biomarkers. The potential clinical applications of these biomarkers, along with novel approaches to their biomarker identification and targeting, are discussed. Additionally, we explore current strategies to overcome immunotherapy resistance and propose incorporating predictive biomarkers into an adaptive clinical trial design, where specific immune signatures guide subsequent treatment selection.

Retrospective Analysis of HLA Class II-Restricted Neoantigen Peptide-Pulsed Dendritic Cell Vaccine for Breast Cancer

Background/Objectives: Neoantigens have attracted attention as ideal therapeutic targets for anti-tumour immunotherapy because the T cells that respond to neoantigens are not affected by central immune tolerance. Recent findings have revealed that the activation of CD4-positive T cells plays a central role in antitumor immunity, and thus targeting human leukocyte antigen (HLA) class II-restricted neoantigens, which are targets of CD4-positive T cells, is of significance. However, there are very few detailed reports of neoantigen vaccine therapies that use an HLA class II-restricted long peptide. In the present study, we retrospectively analysed the ability of HLA class II-restricted neoantigen-pulsed dendritic cell vaccines to induce immune response in five breast cancer patients. Methods: We performed whole exome and RNA sequencing of breast cancer tissues and neoantigen prediction using an in silico pipeline. We then administered dendritic cells pulsed with synthesized an HLA class II-restricted long peptide containing an epitope with high affinity to HLA class I in the lymph node. Results: ELISPOT analysis confirmed that a T-cell response specific for the HLA class II-restricted neoantigen was induced in all cases. TCR repertoire analysis of peripheral blood mononuclear cells before and after treatment in three patients showed increases of specific T-cell clones in two of the three patients. Importantly, no recurrence was observed in all patients. Conclusions: Our analysis demonstrated the immunological efficacy of the HLA class II-restricted neoantigen peptide dendritic cell vaccine against breast cancer and provides useful information for the development of neoantigen vaccine therapy for breast cancer.

Single-cell profiling of acral melanoma infiltrating lymphocytes reveals a suppressive tumor microenvironment

Acral lentiginous melanoma (ALM) is the most common melanoma subtype in non-Caucasians. Despite advances in cancer immunotherapy, current immune checkpoint inhibitors remain unsatisfactory for ALM. Hence, we conducted comprehensive immune profiling using single-cell phenotyping with reactivity screening of the T cell receptors of tumor-infiltrating T lymphocytes (TILs) in ALM. Compared with cutaneous melanoma, ALM showed a lower frequency of tumor-reactive CD8 clusters and an enrichment of regulatory T cells with direct tumor recognition ability, suggesting a suppressive immune microenvironment in ALM. Tumor-reactive CD8 TILs showed heterogeneous expression of coinhibitory molecules, including KLRC1 (NKG2A), in subpopulations with therapeutic implications. Overall, our study provides a foundation for enhancing the efficacy of immunotherapy in ALM.

A theranostic photosensitizer-conjugated albumin co-loading with resiquimod for cancer-targeted imaging and robust photo-immunotherapy

Cancer immunotherapy remains a low immune response rate in clinic because of dominant immunosuppressive tumor microenvironment (TME) and lack of effective drug to specifically remodel the TME. In this work, we introduced a tumor-seeking human serum albumin (HSA) based delivery platform by covalently conjugating with a tumor-targeting near-infrared (NIR) photosensitizer (IR-DBI) and non-covalently loading of immune modulator Resiquimod (R848). HSA exhibited tumor-preferential accumulation after covalent conjugation with IR-DBI. Meanwhile, HSA restricted the rotation of IR-DBI, narrowed the HOMO-LUMO energy gap, significantly enhanced fluorescent intensity and dual-modal phototherapy (PTT/PDT). The enhanced phototherapeutic effect further induced robust ICD effect. More importantly, non-covalent loading of R848 could be released from HSA at tumor sites by laser irradiation-induced heat. The in-situ release of R848 in TME efficiently promoted the maturation of DC cells and repolarized M2 macrophages to M1 macrophages. Consequently, robust photo-induced antitumor immunity was triggered in the different mice models bearing primary and distant tumors or lung metastasis, which was further enhanced by combining with CTLA-4 blockade therapy. Taken together, this work may present a versatile albumin composite which exhibits tumor-preferential accumulation and imaging-guided PDT/PTT/immunotherapy.

Research progress of paclitaxel nanodrug delivery system in the treatment of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, characterized by the loss or low expression of estrogen receptor (ER), human epidermal growth factor receptor 2 (HER2) and progesterone receptor (PR). Due to the lack of clear therapeutic targets, paclitaxel (PTX) is often used as a first-line standard chemotherapy drug for the treatment of high-risk and locally advanced TNBC. PTX is a diterpenoid alkaloid extracted and purified from Taxus plants, functioning as an anticancer agent by inducing and promoting tubulin polymerization, inhibiting spindle formation in cancer cells, and preventing mitosis. However, its clinical application is limited by low solubility and high toxicity. Nanodrug delivery system (NDDS) is one of the feasible methods to improve the water solubility of PTX and reduce side effects. In this review, we summarize the latest advancements in PTX-targeted NDDS, as well as its combination with other codelivery therapies for TNBC treatment. NDDS includes passive targeting, active targeting, stimuli-responsive, codelivery, and multimode strategies. These systems have good prospects in improving the bioavailability of PTX, enhancing tumor targeting, reducing toxicity, controlling drug release, and reverse tumor multidrug resistance (MDR). This review provides valuable insights into the clinical development and application of PTX-targeted NDDS in the treatment of TNBC.

A dendritic cell vaccine for both vaccination and neoantigen-reactive T cell preparation for cancer immunotherapy in mice

Adoptive cell transfer (ACT) using neoantigen-specific T cells is an effective immunotherapeutic strategy. However, the difficult isolation of neoantigen-specific T cells limits the clinical application of ACT. Here, we propose a method to prepare neoantigen-reactive T cells (NRT) for ACT following immunization with a tumor lysate-loaded dendritic cell (DC) vaccine. We show that the DC vaccine not only induces a neoantigen-reactive immune response in lung cancer-bearing mice in vivo, but also facilitate NRT cell preparation in vitro. Adoptive transfer of the NRTs as combinatorial therapy into DC vaccine-immunized, LL/2 tumor-bearing mice allows infiltration of the infused NRTs, as well as the enrichment of neoantigen reactive, non-ACT/NRT T cells into the tumor microenvironment with the function of these neoantigen-reactive T-cell receptors validated in vitro. In summary, we propose a method for preparing NRTs that increases ACT efficacy and paves the way to the design of personalized immunotherapies.

CD94 deficiency or blockade unleashes the anti-tumor immunity in mice and humanized murine models

NKG2 family members have emerged as promising targets in tumor immunotherapy. CD94 can dimerize with both inhibitory and activating NKG2 proteins, while the overall effect and value of targeting CD94 on anti-tumor immunity are unclear. Here, it is shown that the expression of CD94 is upregulated on tumor-infiltrating natural killer (NK) cells and CD8+ T cells, and is related to their exhausted characteristics. Tumor-bearing CD94 knockout (CD94-KO) mice exhibit delayed tumor growth, decreased lung metastases, and prolonged survival. Single cell RNA-seq reveals a remodeled tumor microenvironment in CD94-KO mice, with a reduction in immunosuppressive cells and an increase in anti-tumor immune cells. Moreover, NK cells and CD8+ T cells become proliferative and strongly tumoricidal in CD94-KO mice, thus contributing to the tumor inhibition effect of CD94 deficiency. Treatment with a humanized anti-CD94 blocking antibody (h15C10) alone, in tumor-bearing humanized mouse, delays tumor progression, and improves the therapeutic efficacy of PD-L1 blockade through combination therapy. Our study indicates that CD94 may work as a candidate target in checkpoint immunotherapy.