Neoantigens: promising targets for cancer therapy

A targeted MAVS fusion protein for controlled innate immune activation and antitumor therapy

Targeted therapies leveraging the innate immune system are emerging as promising cancer treatments. The mitochondrial antiviral signaling protein (MAVS) plays a crucial role in initiating innate immune responses, but its clinical use is limited by the risk of uncontrolled activation and systemic toxicity. To address this, we developed a novel therapeutic agent, the truncated interferon activation switch (TRIAS), combining MAVS truncates with a tumor antigen-targeting single-chain variable fragment (scFv). This design ensures antigen-dependent, controlled activation. Lentiviral delivery of TRIAS induced significant antitumor responses, including complete tumor regression in some cases. Flow cytometry (FCM) analysis further confirmed that tumor cells were the predominant population expressing the transgene. TRIAS-expressing tumor cells exhibited enhanced antitumor activity, likely due to increased cytokine release and upregulated major histocompatibility complex (MHC) expression, enabling tumor cells to function as antigen-presenting cells. This activated other immune cells, driving adaptive immune responses. Additionally, TRIAS promoted a proinflammatory shift in the tumor microenvironment (TME). In conclusion, TRIAS was validated as an innovative immunotherapeutic agent with MAVS-like immune-activating properties and tightly controlled mechanisms, offering a safer and more effective approach for clinical cancer immunotherapy.

Effective design of therapeutic nanovaccines based on tumor neoantigens

Neoantigen vaccines are among the most potent immunotherapies for personalized cancer treatment. Therapeutic vaccines containing tumor-specific neoantigens that elicit specific T cell responses offer the potential for long-term clinical benefits to cancer patients. Unlike immune-checkpoint inhibitors (ICIs), which rely on pre-existing specific T cell responses, personalized neoantigen vaccines not only promote existing specific T cell responses but importantly stimulate the generation of neoantigen-specific T cells, leading to the establishment of a persistent specific memory T cell pool. The review discusses the current state of clinical research on neoantigen nanovaccines, focusing on the application of vectors, adjuvants, and combinational strategies to address a range of challenges and optimize therapeutic outcomes.

Restoring tumor antigenicity activates the "bystander" T cell immune cycle

Tumor-specific T cells play a crucial role in tumor immunity. However, these cells are often scarce and functionally exhausted within the tumor microenvironment (TME), leading to the limited efficacy of immunotherapy in many cancer patients. In contrast, increasing evidence suggests that the TME is rich in "bystander" T cells (TBYS), most of which are virus-specific and unrelated to the tumor. These TBYS cells retain functional memory characteristics and the potential to kill tumor cells. To utilize TBYS cells in the TME for tumor elimination, we designed an intracellular delivery system, ASCP, encoding a TBYS epitope to redirect tumor cell antigen specificity toward pre-existing TBYS cells, resulting in effective tumor inhibition in multiple preclinical models. The ASCP-antigen peptide strategy restores the antigenicity of tumor cells and induces epitope spreading of tumor antigens, thereby eliciting more diverse tumor-specific T cell responses. Remarkably, this strategy incorporates MHC-II epitopes containing unnatural amino acids (p-nitrophenylalanine, termed NiraTh), which stimulate CD4+ T cell-mediated immunity and assist CD8+ T cells in clearing tumors. Overall, the ASCP-mediated tumor antigen reprogramming strategy provides important insights for cancer immunotherapy in populations with a history of common viral infections.

Transforming tumors into 'high-risk bombs' triggers a neoantigen storm and amplifies immune responses

Although various immunotherapies have improved the treatment of several challenging malignancies in clinical applications, current research suggests that neoantigens remain fundamental to the initiation of immunotherapy, implying a dependence on high mutation loads in tumors and stable target antigens. To overcome these limitations, we propose a novel immunotherapy paradigm that interferes with splicing to induce the expression of neoantigens and neoepitopes while simultaneously blocking autophagy to prevent their degradation through endogenous pathways. This approach ensures the stable expression and accumulation of neoantigens and neoepitopes in tumor cells. To fully unleash the potential of neoantigens, we further induce tumors to undergo immunogenic cell death (ICD), triggering a "neoantigen storm" at the tumor site to recruit and activate more dendritic cells (DCs). Through a DC-dependent mechanism, communication between the tumor and the tumor-draining lymph node (TDLN) is enhanced, summoning more neoantigen-specific cytotoxic T lymphocytes to lyse tumor cells and establish immune circulation. In summary, this work presents a novel antigen-based immune sensitization strategy that stabilizes target antigens while exploring the potential of non-targeted antigens. By bypassing the cumbersome neoantigen identification process, this strategy holds promise for rapid clinical application in combination with other immunotherapies.

Engineered Proteins and Chemical Tools to Probe the Cell Surface Proteome

The cell surface proteome, or surfaceome, is the hub for cells to interact and communicate with the outside world. Many disease-associated changes are hard-wired within the surfaceome, yet approved drugs target less than 50 cell surface proteins. In the past decade, the proteomics community has made significant strides in developing new technologies tailored for studying the surfaceome in all its complexity. In this review, we first dive into the unique characteristics and functions of the surfaceome, emphasizing the necessity for specialized labeling, enrichment, and proteomic approaches. An overview of surfaceomics methods is provided, detailing techniques to measure changes in protein expression and how this leads to novel target discovery. Next, we highlight advances in proximity labeling proteomics (PLP), showcasing how various enzymatic and photoaffinity proximity labeling techniques can map protein-protein interactions and membrane protein complexes on the cell surface. We then review the role of extracellular post-translational modifications, focusing on cell surface glycosylation, proteolytic remodeling, and the secretome. Finally, we discuss methods for identifying tumor-specific peptide MHC complexes and how they have shaped therapeutic development. This emerging field of neo-protein epitopes is constantly evolving, where targets are identified at the proteome level and encompass defined disease-associated PTMs, complexes, and dysregulated cellular and tissue locations. Given the functional importance of the surfaceome for biology and therapy, we view surfaceomics as a critical piece of this quest for neo-epitope target discovery.

RNA modifications in the tumor microenvironment: insights into the cancer-immunity cycle and beyond

The chemical modification of biological molecules is a critical regulatory mechanism for controlling molecular functions. Although research has long focused on DNA and proteins, RNA modifications have recently attracted substantial interest with the advancement in detection technologies. In oncology, many studies have identified dysregulated RNA modifications including m6A, m1A, m5C, m7G, pseudouridylation and A to I editing, leading to disrupted downstream pathways. As the concept of the tumor microenvironment has gained prominence, studies have increasingly examined the role of RNA modifications in this context, focusing on interactions among cancer cells, immune cells, stromal cells, and other components. Here we review the RNA modifications in the tumor microenvironment through the perspective of the Cancer-Immunity Cycle. The extracellular RNA modifications including exosomes and influence of microbiome in RNA modifications are potential research questions. Additionally, RNA modifying enzymes including FTO, ALKBH5, METTL3, PUS7 are under investigation as potential biomarkers and targets for combination with immunotherapies. ADCs and mimetics of modified RNA could be potential novel drugs. This review discusses the regulatory roles of RNA modifications within the tumor microenvironment.

Polyamine-Depleting Hydrogen-Bond Organic Frameworks Unleash Dendritic Cell and T Cell Vigor for Targeted CRISPR/Cas-Assisted Cancer Immunotherapy

Polyamines have tantalized cancer researchers as a potential means to rein in the rampant growth of cancer cells. However, clinical trials in recent decades have disappointed in delivering notable progress. Herein, a microfluidic-assisted synthetic hydrogen-bond organic framework (HOF) as a polyamine-depleting nanoplatforms designed to unleash the vigor of both dendritic cells (DCs) and T cells for precision cancer immunotherapy is reported. Upon internalization by tumor cells, the loaded plasma amine oxidase (PAO) in HOF efficiently depletes polyamines, remolding the tumor microenvironment and alleviating T-cell immunosuppression. This process also generates acrolein and H2O2, triggering CRISPR-assisted neoantigen generation. Specifically, Acrolein induces carbonyl stress, increasing mutational burdens. Simultaneously, HOF leverages the energy from the bis[2,4,5-trichloro-6-(pentyloxycarbonyl)phenyl] oxalate (CPPO)-H2O2 reaction for CRET-triggered singlet oxygen production, leading to thioether bond cleavage and release CRISPR-Cas9. Once released, CRISPR-Cas9 knocks out the DNA mismatch repair (MMR)-related MLH1 gene, further elevating mutational burdens and generating neoantigens, ideal targets for DCs. This dual-action strategy not only corrects T-cell immunosuppression but also enhances DC efficacy, presenting a powerful approach for tumor immunotherapy.

Therapeutic potential of flavonoids in gastrointestinal cancer: Focus on signaling pathways and improvement strategies (Review)

Flavonoids are a group of polyphenolic compounds distributed in vegetables, fruits and other plants, which have considerable antioxidant, anti‑tumor and anti‑inflammatory activities. Several types of gastrointestinal (GI) cancer are the most common malignant tumors in the world. A large number of studies have shown that flavonoids have inhibitory effects on cancer, and they are recognized as a class of potential anti‑tumor drugs. Therefore, the present review investigated the molecular mechanisms of flavonoids in the treatment of different types of GI cancer and summarized the drug delivery systems commonly used to improve their bioavailability. First, the classification of flavonoids and the therapeutic effects of various flavonoids on human diseases were briefly introduced. Then, to clarify the mechanism of action of flavonoids on different types of GI cancer in the human body, the metabolic process of flavonoids in the human body and the associated signaling pathways causing five common types of GI cancer were discussed, as well as the corresponding therapeutic targets of flavonoids. Finally, in clinical settings, flavonoids have poor water solubility, low permeability and inferior stability, which lead to low absorption efficiency in vivo. Therefore, the three most widely used drug delivery systems were summarized. Suggestions for improving the bioavailability of flavonoids and the focus of the next stage of research were also put forward.

Enhancing immunotherapy with tumour-responsive nanomaterials

The targeted delivery of immunotherapies to tumours using tumour-responsive nanomaterials is a promising area of cancer research with the potential to address the limitations of systemic administration such as on-target off-tumour toxicities and a lack of activity owing to the immunosuppressive tumour microenvironment (TME). Attempts to address these challenges include the design and functionalization of nanomaterials capable of releasing their cargoes in response to specific TME characteristics, thus facilitating the targeted delivery of immune-checkpoint inhibitors, cytokines, mRNAs, vaccines and, potentially, chimaeric antigen receptors as well as of agents that modulate the extracellular matrix and induce immunogenic cell death. In this Review, we describe these various research efforts in the context of the dynamic properties of the TME, such as pH, reductive conditions, reactive oxygen species, hypoxia, specific enzymes, high levels of ATP and locoregional aspects, which can be leveraged to enhance the specificity and efficacy of nanomaterial-based immunotherapies. Highlighting preclinical successes and ongoing clinical trials, we evaluate the current landscape and potential of these innovative approaches. We also consider future research directions as well as the most important barriers to successful clinical translation, emphasizing the transformative potential of tumour-responsive nanomaterials in overcoming the barriers that limit the activity of traditional immunotherapies, thus improving patient outcomes.

Subtype-Specific Patterns of Tumor Purity and Mutation Load Suggest Treatment Implications: A Cross-Sectional Analysis of 7494 Soft Tissue and Bone Sarcomas (MSK Cohort)

OBJECTIVES

Sarcomas are complex mesenchymal malignancies whose molecular characteristics can significantly influence treatment strategies. This study aimed to investigate the relationship between tumor purity, mutation load, and clinical characteristics across sarcoma subtypes, focusing on potential implications for therapeutic stratification.

METHODS

This study analyzed the molecular characteristics of 7494 sarcoma cases from the Soft Tissue and Bone Sarcoma (MSK, Nat Commun 2022) data set using available case analysis. Correlations between tumor purity, mutation load, age, and sex were analyzed using nonparametric methods, with subtype-specific analyses conducted using Kruskal-Wallis tests and Bonferroni-corrected post hoc comparisons. A comprehensive analysis of mutation patterns was performed using microsatellite instability (MSI) status.

RESULTS

Significant correlations between mutation load and tumor purity (ρ=0.320, P <0.001) were identified, with marked heterogeneity across subtypes. Tumor purity ranged from 20.0% in brain sarcomas to 78.5% in dermatofibrosarcoma protuberans. Age-related molecular changes were observed in brain (ρ=0.711, P =0.006) and skin sarcomas (ρ=0.450, P =0.006), suggesting distinct evolutionary patterns. A subset of hypermutated, microsatellite stable cases (0.15%) with mutation loads exceeding 100 mutations/mb were identified, suggesting alternative mechanisms of genomic instability. MSI-high status was rare (0.24%) but associated with higher mutation loads (median: 25.84 vs. 2.42, P <0.001), particularly in uterine sarcomas (0.7% prevalence).

CONCLUSIONS

The identification of distinct molecular patterns across sarcoma subtypes challenge existing morphology-based classification systems and may hold implications for therapeutic stratification. These findings may help inform future immunotherapeutic and molecular-guided approaches to treatment in sarcoma patients, particularly for elderly patients with brain sarcomas or females with uterine sarcomas.

Clinical benefit of immune checkpoint inhibitors in elderly cancer patients: Current evidence from immunosenescence pathophysiology to clinical trial results

The age-related decline in immunity appears to be associated not only with cancer development but also with differential responses to immune checkpoint inhibitors (ICIs). Despite their increasing utility across various malignancies and therapeutic settings, limited data -derived primarily from subgroup analyses of randomized controlled trials (RCTs), pooled meta-analyses, and retrospective studies- are available on the effects of aging on their efficacy and toxicity. Immunosenescence, characterized by the progressive decline of the function of the immune system, and inflammaging, a state of persistent low-grade sterile inflammation, may influence ICI outcomes. Additionally, the incidence, severity, and subtypes of immune-related adverse events (irAEs) may differ between older and younger individuals due to loss of immunotolerance. In the current review, starting from a a comprehensive discussion of the pathophysiology of immunosenescence, we proceed to critically review age-related retrospective and randomized evidence supporting FDA-approved ICIs. We highlight similarities or differences across age groups and the clinical benefit of ICIs in elderly versus younger cancer patients. The optimal integration of ICIs in geriatric oncology necessitates greater inclusion of this patient demographic in RCTs along with real-world data in order to acquire robust data which will guide evidence-based treatment decisions for this population.

Advances in Therapeutic Cancer Vaccines, Their Obstacles, and Prospects Toward Tumor Immunotherapy

Over the past few decades, cancer immunotherapy has experienced a significant revolution due to the advancements in immune checkpoint inhibitors (ICIs) and adoptive cell therapies (ACTs), along with their regulatory approvals. In recent times, there has been hope in the effectiveness of cancer vaccines for therapy as they have been able to stimulate de novo T-cell reactions against tumor antigens. These tumor antigens include both tumor-associated antigen (TAA) and tumor-specific antigen (TSA). Nevertheless, the constant quest to fully achieve these abilities persists. Therefore, this review offers a broad perspective on the existing status of cancer immunizations. Cancer vaccine design has been revolutionized due to the advancements made in antigen selection, the development of antigen delivery systems, and a deeper understanding of the strategic intricacies involved in effective antigen presentation. In addition, this review addresses the present condition of clinical tests and deliberates on their approaches, with a particular emphasis on the immunogenicity specific to tumors and the evaluation of effectiveness against tumors. Nevertheless, the ongoing clinical endeavors to create cancer vaccines have failed to produce remarkable clinical results as a result of substantial obstacles, such as the suppression of the tumor immune microenvironment, the identification of suitable candidates, the assessment of immune responses, and the acceleration of vaccine production. Hence, there are possibilities for the industry to overcome challenges and enhance patient results in the coming years. This can be achieved by recognizing the intricate nature of clinical issues and continuously working toward surpassing existing limitations.

Advancing personalized immunotherapy for melanoma: Integrating immunoinformatics in multi-epitope vaccine development, neoantigen identification via NGS, and immune simulation evaluation

The use of cancer vaccines represents a promising avenue in cancer immunotherapy. Advances in next-generation sequencing (NGS) technology, coupled with the development of sophisticated analysis tools, have enabled the identification of somatic mutations by comparing genetic sequences between normal and tumor samples. Tumor neoantigens, derived from these mutations, have emerged as potential candidates for therapeutic cancer vaccines. In this study, raw NGS data from two melanoma patients (NCI_3903 and NCI_3998) were analyzed using publicly available SRA datasets from NCBI to identify patient-specific neoantigens. A comprehensive pipeline was employed to select candidate peptides based on their antigenicity, immunogenicity, physicochemical properties, and toxicity profiles. These validated epitopes were utilized to design multi-epitope chimeric vaccines tailored to each patient. Peptide linkers were employed to connect the epitopes, ensuring optimal vaccine structure and function. The two-dimensional (2D) and three-dimensional (3D) structures of the chimeric vaccines were predicted and refined to ensure structural stability and immunogenicity. Furthermore, molecular docking simulations were conducted to evaluate the binding interactions between the vaccine chimeras and the HLA class I receptors, confirming their potential to elicit a robust immune response. This work highlights a personalized approach to cancer vaccine development, demonstrating the feasibility of utilizing neoantigen-based immunoinformatics pipelines to design patient-specific therapeutic vaccines for melanoma.

Fabrication and functional validation of a hybrid biomimetic nanovaccine (HBNV) against Kit K641E -mutant melanoma

Cancer nanovaccines hold the promise for personalization, precision, and pliability by integrating all the elements essential for effective immune stimulation. An effective immune response requires communication and interplay between antigen-presenting cells (APCs), tumor cells, and immune cells to stimulate, extend, and differentiate antigen-specific and non-specific anti-tumor immune cells. The versatility of nanomedicine can be adapted to deliver both immunoadjuvant payloads and antigens from the key players in immunity (i.e., APCs and tumor cells). The imperative for novel cancer medicine is particularly pressing for less common but more devastating KIT-mutated acral and mucosal melanomas that are resistant to small molecule c-kit and immune checkpoint inhibitors. To overcome this challenge, we successfully engineered nanotechnology-enabled hybrid biomimetic nanovaccine (HBNV) comprised of membrane proteins (antigens to activate immunity and homing/targeting ligand to tumor microenvironment (TME) and lymphoid organs) from fused cells (of APCs and tumor cells) and immunoadjuvant. These HBNVs are efficiently internalized to the target cells, assisted in the maturation of APCs via antigens and adjuvant, activated the release of anti-tumor cytokines/inhibited the release of immunosuppressive cytokine, showed a homotypic effect on TME and lymph nodes, activated the anti-tumor immune cells/downregulated the immunosuppressive immune cells, reprogram the tumor microenvironment, and showed successful anti-tumor therapeutic and prophylactic effects.

Evoking the Cancer-immunity cycle by targeting the tumor-specific antigens in Cancer immunotherapy

Cancer-related deaths continue to rise, largely due to the suboptimal efficacy of current treatments. Fortunately, immunotherapy has emerged as a promising alternative, offering new hope for cancer patients. Among various immunotherapy approaches, targeting tumor-specific antigens (TSAs) has gained particular attention due to its demonstrated success in clinical settings. Despite these advancements, there are still gaps in our understanding of TSAs. Therefore, this review explores the life cycle of TSAs in cancer, the methods used to identify them, and recent advances in TSAs-targeted cancer therapies. Enhancing medical professionals' understanding of TSAs will help facilitate the development of more effective TSAs-based cancer treatments.

CAR T cells in lung cancer: Targeting tumor-associated antigens to revolutionize immunotherapy

Tumor-targeted T cells engineered for targeting and killing tumor cells have revolutionized cancer treatment, specifically in hematologic malignancies, through chimeric antigen receptor (CAR) T cell therapy. However, the migration of this success to lung cancer is challenging due to the tumor microenvironment (TME), antigen heterogeneity, and limitations of T cell infiltration. This review aims to evaluate current strategies addressing these barriers, focusing on the optimization of tumor-associated antigen (TAA) targeting, such as epidermal growth factor receptor (EGFR), mucin-1 (MUC1), and mesothelin (MSLN), which are frequently overexpressed in lung cancer and offer promising targets for CAR T-cell therapy. In this review, we discuss recent progress in CAR T cell engineering, applying enhanced costimulatory molecules, cytokine-secreting CAR T cells, and engineered modifications to improve T cell resilience in immunosuppressive environments. Additionally, this review also evaluates combination therapies of immune checkpoint inhibitors and recently published clinical trials on lung cancer with CAR T cells. We offer insights into the way to optimize CAR T cell therapy for lung cancer by analyzing antigen selection, immune evasion, and the strategies to enhance T cell persistence and tumor infiltration.

Microenvironment-based immunotherapy in oral cancer: a comprehensive review

Oral cancer, a prevalent form of head and neck malignancy, accounts for 4% of global cancer cases. The most common type, oral squamous cell carcinoma (OSCC), has a survival rate of about 50%. Even though emerging molecular therapies show promise for managing oral cancer, current treatments like surgery, radiotherapy, and chemotherapy have significant side effects. In addition, the complex tumor microenvironment (TME), involving the extracellular matrix (ECM) and cells like fibroblasts and stromal cells like immune cells, promotes tumor growth and inhibits immune responses, complicating treatment. Nonetheless, immunotherapy is crucial in cancer treatment, especially in oral cancers. Indeed, its effectiveness lies in targeting immune checkpoints such as PD-1 and CTLA-4 inhibitors, as well as monoclonal antibodies like pembrolizumab and cetuximab, adoptive cell transfer methods (including CAR-T cell therapy), cytokine therapy such as IL-2, and tumor vaccines. Thus, these interventions collectively regulate tumor proliferation and metastasis by targeting the TME through autocrine-paracrine signaling pathways. Immunotherapy indeed aims to stimulate the immune system, leveraging both innate and adaptive immunity to counteract cancer cell signals and promote tumor destruction. This review will explore how the TME controls tumor proliferation and metastasis via autocrine-paracrine signaling pathways. It will then detail the effectiveness of immunotherapy in oral cancers, focusing on immune checkpoints, targeted monoclonal antibodies, adoptive cell transfer, cytokine therapy, and tumor vaccines.

Tailoring nanovectors for optimal neoantigen vaccine efficacy

The primary objective of neoantigen vaccines is to elicit a robust anti-tumor immune response by generating neoantigen-specific T cells that can eradicate tumor cells. Despite substantial advancements in personalized neoantigen prediction using next-generation sequencing, machine learning, and mass spectrometry, challenges remain in efficiently expanding neoantigen-specific T cell populations in vivo. This challenge impedes the widespread clinical application of neoantigen vaccines. Nanovector-based neoantigen delivery systems have emerged as a promising solutions to this challenge. These nanovectors offer several advantages, such as enhanced stability, targeted intracellular delivery, sustained release, and improved antigen-presenting cell (APC) activation. Notably, they effectively deliver various neoantigen vaccine formulations (DC cell-based, synthetic long peptide (SLP)-based or DNA/mRNA-based) to APCs or T cells, thereby activating both CD4+ T and CD8+ T cells. This ultimately induces a specific anti-tumor immune response. This review focuses on recent innovations in neoantigen vaccine delivery vectors. We aim to identify optimal design parameters for vectors tailored to different neoantigen vaccine types, with an emphasis on enhancing the tumor microenvironment and stimulating the production of neoantigen-specific cytotoxic T cells. By maximizing the potential of these delivery systems, we aim to accelerate the clinical translation of neoantigen nanovaccines and advance cancer immunotherapy.

Non-Viral RNA Therapies for Non-Small Cell Lung Cancer and Their Corresponding Clinical Trials

Ribonucleic acid (RNA)-based therapies represent a promising class of drugs for the treatment of non-small cell lung cancer (NSCLC) due to their ability to modulate gene expression. Therapies leveraging small interfering RNA (siRNA), messenger RNA (mRNA), microRNA (miRNA), and antisense oligonucleotides (ASOs) offer various advantages over conventional treatments, including the ability to target specific genetic mutations and the potential for personalized medicine approaches. However, the clinical translation of these therapeutics for the treatment of NSCLC faces challenges in delivery due to their immunogenicity, negative charge, and large size, which can be mitigated with delivery platforms. In this review, we provide a description of the pathophysiology of NSCLC and an overview of RNA-based therapeutics, specifically highlighting their potential application in the treatment of NSCLC. We discuss relevant classes of RNA and their therapeutic potential for NSCLC. We then discuss challenges in delivery and non-viral delivery strategies such as lipid- and polymer-based nanoparticles that have been developed to address these issues in preclinical models. Furthermore, we provide a summary table of clinical trials that leverage RNA therapies for NSCLC [which includes their National Clinical Trial (NCT) numbers] to highlight the current progress in NSCLC. We also discuss how these NSCLC therapies can be integrated with existing treatment modalities to enhance their efficacy and improve patient outcomes. Overall, we aim to highlight non-viral strategies that tackle RNA delivery challenges while showcasing RNA's potential as a next-generation therapy for NSCLC treatment.

Thermoresistant flagellin-adjuvanted cancer vaccine combined with photothermal therapy synergizes with anti-PD-1 treatment

BACKGROUND

Cancer immunotherapy, leveraging the immune system to target and eradicate cancer cells, has transformed cancer treatment paradigms. Immune checkpoint inhibitors (ICIs) are used in a wide array of cancers, but only a limited fraction of patients are responding. Cancer vaccines could elicit antigen-specific immune responses and establish long-term immune memory, preventing recurrence and metastasis. Despite their promising profiles, ICIs and cancer vaccines by themselves are often insufficient to overcome the immunosuppressive tumor microenvironment (TME) and recurrence/metastasis. Addressing these challenges is crucial for improving cancer immunotherapy outcomes.

METHODS

The targeted liposomal formulation (TLIF), displaying Cyclic RGD (cRGD) peptide on the surface and encapsulating ICG and thermoresistant flagellin (FlaB) inside, was used for photothermal therapy (PTT), which was designed to induce robust immunogenic cell death (ICD) and release tumor antigens (TAs). We employed a mouse breast cancer model amenable to PTT. Utilizing a bilateral DD-Her2/neu tumor implantation model, we evaluated local and abscopal effects of combinatorial approaches employing PTT, FlaB-adjuvanted peptide vaccine (FlaB-Vax), and anti-PD-1 treatment. FlaB-Vax was designed to trigger tumor-associated antigen (TAA)-specific immune responses, which will trigger specific anti-tumor immunity. TLIF-PTT aimed to reduce tumor burden and induce ICD-mediated TA liberation for epitope spreading. Sustained anti-tumor immune memory was assessed by orthotopic rechallenging cured mice with the DD-Her2/neu tumor cells.

RESULTS

The combination of TLIF-PTT and FlaB-Vax provided significantly enhanced primary tumor suppression, with strong abscopal effects and long-lasting immune memory. The addition of anti-PD-1 therapy further improved long-term relapse-free survival, highlighting the potential of this combinatorial approach to induce durable antitumor immunity and sustainably prevent cancer recurrence and metastasis.

CONCLUSION

This study demonstrates that the combination of TLIF-PTT and FlaB-Vax synergistically induced synergistic anti-tumor immune responses, which were efficaciously potentiated by anti-PD-1 treatment for recurrence-free long-term survival.

Identification of new immune target and signaling for cancer immunotherapy

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

Autologous Peripheral Vγ9Vδ2 T Cell Synergizes with αβ T Cell Through Antigen Presentation and BTN3A1 Blockade in Immunotherapy of Cervical Cancer

New treatment strategies are urgently needed for patients with advanced cervical cancer (CC). Here, a synergistic anti-CC effect of a novel combinatorial immunotherapy with adoptively transferred autologous Vγ9Vδ2 T cells and αβ T cells is shown. The pivotal role of both circulating and tumor-infiltrating Vγ9Vδ2 T cells in anti-CC immunity is uncovered. Importantly, autologous Vγ9Vδ2 T cells show a synergistic anti-CC effect with αβ T cells not only through killing tumor directly, but also by promoting the activation and tumoricidal activity of syngeneic αβ T cells through antigen presentation, which can be further boosted by conventional chemotherapy. Moreover, Vγ9Vδ2 T cells can restore the tumoricidal function of αβ T cell through competitively binding to BTN3A1, a TCR-Vγ9Vδ2 ligand on CC cells upregulated by IFN-γ derived from activated αβ T cell. These findings uncover a critical synergistic effect of autologous Vγ9Vδ2 T cells and αβ T cells in immunotherapy of CC and reveal the underlying mechanisms.

Translation of bi-directional transcripts enhances MHC-I peptide diversity

Antisense transcripts play an important role in generating regulatory non-coding RNAs but whether these transcripts are also translated to generate functional peptides remains poorly understood. In this study, RNA sequencing and six-frame database generation were combined with mass spectrometry analysis of peptides isolated from polysomes to identify Nascent Pioneer Translation Products (Na-PTPs) originating from alternative reading frames of bi-directional transcripts. Two Na-PTP originating peptides derived from antisense strands stimulated CD8+ T cell proliferation when presented to peripheral blood mononuclear cells (PBMCs) from nine healthy donors. Importantly, an antigenic peptide derived from the reverse strand of two cDNA constructs was presented on MHC-I molecules and induced CD8+ T cell activation. The results demonstrate that three-frame translation of bi-directional transcripts generates antigenic peptide substrates for the immune system. This discovery holds significance for understanding the origin of self-discriminating peptide substrates for the major histocompatibility class I (MHC-I) pathway and for enhancing immune-based therapies against infected or transformed cells.

The Current Status of T Cell Receptor (TCR) Repertoire Analysis in Colorectal Cancer

The rapid increase in colorectal cancer (CRC) cases recently has highlighted the need to use predictive biomarkers to guide therapeutic approaches. Current studies have focused on the tumor-infiltrating lymphocytes present in the tumor microenvironment (TME), in which cytotoxic T cell activation and the amount are associated with CRC patient prognosis. The T cell receptor (TCR) is essential for antigen recognition and T cell identification, playing a central role in cancer immunotherapy. The T cell status reflects TCR diversity or clonality, known as the TCR repertoire. Accordingly, analyzing the TCR repertoire dynamics may help predict the immunological circumstances of the TME in a timely way. In this review, we summarize the TCR repertoire-related knowledge, including its potential use as predictive biomarkers in CRC. The intratumoral TCR repertoire is restricted in CRC patients compared with healthy individuals, as well as in peripheral blood. Patients with deficient mismatch repair display more restriction than those with proficient mismatch repair. Importantly, a higher TCR diversity before treatment and a decrease following treatment may indicate a good response and a better clinical outcome in CRC patients. The future use of TCR repertoire sequencing technology combined with artificial intelligence-based analysis is a potential strategy for CRC therapeutic decision making.

The Influence of Indisulam on Human Immune Effector Cells: Is a Combination with Immunotherapy Feasible?

Background: As a modulator of pre-mRNA splicing, the anti-cancer agent indisulam can induce aberrantly spliced neoantigens, enabling immunologic anti-tumor activity. Consequently, combining indisulam with immunotherapy is expected to be a promising novel approach in cancer therapy. However, a prerequisite for such a combination is that immune effector cells remain functional and unharmed by the chemical. Methods: To ensure the immunocompetence of human immune effector cells is maintained, we investigated the influence of indisulam on ex vivo-isolated T cells and monocyte-derived dendritic cells (moDCs) from healthy donors. We used indisulam concentrations from 0.625 µM to 160 µM and examined the impact on the following: (i) the activation of CD4+ and CD8+ T cells by CD3-crosslinking and via a high-affinity TCR, (ii) the cytotoxicity of CD8+ T cells, (iii) the maturation process of moDCs, and (iv) antigen-specific CD8+ T cell priming. Results: We observed dose-dependent inhibitory effects of indisulam, and substantial inhibition occurred at concentrations around 10 µM, but the various functions of the immune system exhibited different sensitivities. The weaker activation of T cells via CD3-crosslinking was more sensitive than the stronger activation via the high-affinity TCR. T cells remained capable of killing tumor cells after treatment with indisulam up to 40 µM, but T cell cytotoxicity was impaired at 160 µM indisulam. While moDC maturation was also rather resistant, T cell priming was almost completely abolished at a concentration of 10 µM. Conclusions: These effects should be considered in possible future combinations of immunotherapy with the mRNA splicing inhibitor indisulam.

Advancements and challenges in personalized neoantigen-based cancer vaccines

Advancements in personalized neoantigen-based cancer vaccines are ushering in a new era in oncology, targeting unique genetic alterations within tumors to enhance treatment precision and efficacy. Neoantigens, specific to cancer cells and absent in normal tissues, are at the heart of these vaccines, promising to direct the immune system specifically against the tumor, thereby maximizing therapeutic efficacy while minimizing side effects. The identification of neoantigens through genomic and proteomic technologies is central to developing these vaccines, allowing for the precise mapping of a tumor's mutational landscape. Despite advancements, accurately predicting which neoantigens will elicit strong immune responses remains challenging due to tumor variability and the complexity of immune system interactions. This necessitates further refinement of bioinformatics tools and predictive models. Moreover, the efficacy of these vaccines heavily depends on innovative delivery methods that enhance neoantigen presentation to the immune system. Techniques like encapsulating neoantigens in lipid nanoparticles and using viral vectors are critical for improving vaccine stability and delivery. Additionally, these vaccines contribute towards achieving Sustainable Development Goal 3.8, promoting universal health coverage by advancing access to safe and effective cancer treatments. This review delves into the potential of neoantigen-based vaccines to transform cancer treatment, examining both revolutionary advancements and the ongoing challenges they face.

Engineered dendritic cells-derived extracellular vesicles for cancer immunotherapy

Extracellular vesicles (EVs) have emerged as a cell-free therapeutic approach, garnering increasing attention for their potential to enhance the safety and efficacy of immunotherapy. This interest is primarily driven by the biocompatibility and cell/tissue tropism inherent to EVs, but also due to their reconfigurable content. This, termed as cargo, may comprise bioactive molecules as proteins, lipids, and nucleic acids that play a pivotal role in mediating intercellular communication. In particular, dendritic cells-derived extracellular vesicles (DC-EVs) facilitate the transfer of critical components, like antigens and immune-regulatory factors, and due to the expression of major histocompatibility complexes and co-stimulatory molecules on their surface can activate T cells, thereby modulating the immune response. Additionally, DC-EVs can be engineered to transport tumor-specific antigens, cytokines, or other agents in order to strength their immunotherapeutic potential, and even be used in vaccines formulation. In this review, the latest advancements in engineering DC-EVs to improve their immunotherapeutic potential is discussed in detail, while also addressing current challenges associated with DC-EVs therapies.

In Silico Validation of OncoOrigin: An Integrative AI Tool for Primary Cancer Site Prediction with Graphical User Interface to Facilitate Clinical Application

Cancers of unknown primary (CUPs) represent a significant diagnostic and therapeutic challenge in the field of oncology. Due to the limitations of current diagnostic tools in these cases, novel approaches must be brought forward to improve treatment outcomes for these patients. The objective of this study was to develop a machine-learning-based software for primary cancer site prediction (OncoOrigin), based on genetic data acquired from tumor DNA sequencing. By design, this was an in silico diagnostic study, conducted using data from the cBioPortal database (accessed on 21 September 2024) and several data processing and machine learning Python libraries. The study involved over 20,000 tumor samples with information on patient age, sex, and the presence of genetic variants in over 600 genes. The main outcome of interest was machine-learning-based discrimination between cancer site classes. Model quality was assessed by training set cross-validation and evaluation on a segregated test set. Finally, the optimal model was incorporated with a graphical user interface into the OncoOrigin software. Feature importance for class discrimination was also determined on the optimal model. Out of the four tested machine learning estimators, the XGBoostClassifier-based model proved superior in test set evaluation, with a top-2 accuracy of 0.91 and ROC-AUC of 0.97. Unlike other machine learning models published in the literature, OncoOrigin stands out as the only one integrated with a graphical user interface, which is crucial for facilitating its use by oncology specialists in everyday clinical practice, where its application and implementation will have the greatest value in the future.

Neoantigen-based mRNA vaccine exhibits superior anti-tumor activity compared to synthetic long peptides in an in vivo lung carcinoma model

Neoantigen vaccines hold great promise in cancer immunotherapy, but the comparative efficacy of different vaccine platforms, particularly in the context of tumor burden (TB), remains insufficiently studied. In this research, we evaluated the safety and therapeutic efficacy of synthetic long peptide and mRNA-based vaccines, both designed to target identical neoantigens across different Lewis Lung Carcinoma (LLC) tumor burdens. We employed the LLC syngeneic mouse model, a widely used preclinical model for aggressive and immunosuppressive tumors. Our findings demonstrated that the mRNA-based vaccine significantly outperformed the peptide-based vaccine in preventing tumor growth in mice with low TB. These results underscore the potential of mRNA vaccines as a more effective approach for treating aggressive tumors, contributing valuable insights for the future development of neoantigen-based cancer vaccines.

The application of emerging immunotherapy in the treatment of prostate cancer: progress, dilemma and promise

In recent years, there has been a growing trend towards the utilization of immunotherapy techniques for the treatment of cancer. Some malignancies have acquired significant progress with the use of cancer vaccines, immune checkpoint inhibitors, and adoptive cells therapy. Scholars are exploring the aforementioned methods as potential treatments for advanced prostate cancer (PCa) due to the absence of effective adjuvant therapy to improve the prognosis of metastatic castration-resistant prostate cancer (mCRPC). Immunotherapy strategies have yet to achieve significant advancements in the treatment of PCa, largely attributed to the inhibitory tumor microenvironment and low mutation load characteristic of this malignancy. Hence, researchers endeavor to address these challenges by optimizing the design and efficacy of immunotherapy approaches, as well as integrating them with other therapeutic modalities. To date, studies have also shown potential clinical benefits. This comprehensive review analyzed the utilization of immunotherapy techniques in the treatment of PCa, assessing their advantages and obstacles, with the aim of providing healthcare professionals and scholars with a comprehensive understanding of the progress in this field.

TCR-T cell therapy for solid tumors: challenges and emerging solutions

With the use of T cell receptor T cells (TCR-T cells) and chimeric antigen receptor T cells (CAR-T cells), T-cell immunotherapy for cancer has advanced significantly in recent years. CAR-T cell therapy has demonstrated extraordinary success when used to treat hematologic malignancies. Nevertheless, there are several barriers that prevent this achievement from being applied to solid tumors, such as challenges with tumor targeting and inadequate transit and adaption of genetically modified T-cells, especially in unfavorable tumor microenvironments The deficiencies of CAR-T cell therapy in the treatment of solid tumors are compensated for by TCR-T cells, which have a stronger homing ability to initiate intracellular commands, 90% of the proteins can be used as developmental targets, and they can recognize target antigens more broadly. As a result, TCR-T cells may be more effective in treating solid tumors. In this review, we discussed the structure of TCR-T and have outlined the drawbacks of TCR-T in cancer therapy, and suggested potential remedies. This review is crucial in understanding the current state and future potential of TCR-T cell therapy. We emphasize how important it is to use combinatorial approaches, combining new combinations of various emerging strategies with over-the-counter therapies designed for TCR-T, to increase the anti-tumor efficacy of TCR-T inside the TME and maximize treatment safety, especially when it comes to solid tumor immunotherapies.

Hybrid lipid nanoparticles with tumor antigen-primed dendritic cell membranes for post-surgical tumor immunotherapy

Post-surgical tumor recurrence poses a major challenge in cancer treatment due to residual tumor cells and surgery-induced immunosuppression. Here, we developed hybrid nanoparticles, termed T-DCNPs, designed to promote antigen-specific activation of cytotoxic CD8+ T cells while concurrently inhibiting immunosuppressive pathways within the tumor microenvironment. T-DCNPs were formulated by co-extruding lipid nanoparticles containing a transforming growth factor β inhibitor with dendritic cells that were pre-treated with autologous neoantigens derived from surgically excised tumors. By using whole tumor antigens rather than specific peptides, T-DCNPs effectively overcame tumor heterogeneity and elicited a robust, targeted immune response. In vitro studies showed that T-DCNPs enhanced CD8+ T cell proliferation and reduced programmed death-1 (PD-1) expression, leading to increased antitumor cytotoxicity. In vivo experiments, involving intratumoral injections of T-DCNPs in distant tumor and post-surgical melanoma models, demonstrated a significant reduction in distant tumor growth, decreased recurrence rates, and extended survival compared to control groups. Flow cytometry and immunohistochemistry analyses further confirmed the enhanced infiltration of activated CD8+ T cells and a marked reduction in immunosuppressive markers, including PD-1 and Foxp3, within the treated tumors. These results suggest that T-DCNPs, through the dual mechanisms of tumor antigen-specific T cell activation and immune modulation, offer a promising strategy to prevent tumor recurrence following surgery and could potentially improve the efficacy of postoperative cancer immunotherapy.

Glioblastoma Tumor Microenvironment and Purinergic Signaling: Implications for Novel Therapies

Glial-origin brain tumors, particularly glioblastomas (GBMs), are known for their devastating prognosis and are characterized by rapid progression and fatal outcomes. Despite advances in surgical resection, complete removal of the tumor remains unattainable, with residual cells driving recurrence that is resistant to conventional therapies. The GBM tumor microenviroment (TME) significantly impacts tumor progression and treatment response. In this review, we explore the emerging role of purinergic signaling, especially the P2X7 receptor (P2X7R). Due to its unique characteristics, it plays a key role in tumor progression and offers a potential therapeutic strategy for GBM through TME modulation. We discuss also the emerging role of the P2X4 receptor (P2X4R) as a promising therapeutic target. Overall, targeting purinergic signaling offers a potential approach to overcoming current GBM treatment limitations.

Pan-Cancer Molecular Biomarkers: Practical Considerations for the Surgical Pathologist

Traditional anatomic pathologic classification of cancer is based on tissue of origin and morphologic and immunohistochemical characterization of the malignant cells. With the technological improvements of massively parallel or next-generation sequencing, oncogenic drivers that are shared across different tumor types are increasingly being identified and used as pan-cancer biomarkers. This approach is reflected in the growing list of Food and Drug Administration-approved tumor-agnostic therapies, including pembrolizumab in the setting of microsatellite instability and high tumor mutational burden, larotrectinib and entrectinib for solid tumors with NTRK fusions, and combined dabrafenib-trametinib for BRAF V600E-mutated neoplasms. Several other biomarkers are currently under investigation, including fibroblast growth factor receptor (FGFR), RET, and ROS1 fusions; ERBB2 amplification; and mutations in the AKT1/2/3, NF1, RAS pathway and (mitogen-activated protein kinase (MAPK) pathway. As molecular assays are increasingly incorporated into routine tumor workup, the emergence of additional pan-cancer biomarkers is likely to be a matter more of "when" than "if." In this review, we first explore some of the conceptual and technical considerations at the intersection of surgical and molecular pathology, followed by a brief overview of both established and emerging molecular pan-cancer biomarkers and their diagnostic and clinical applications.

A 5-Year Update on the Clinical Development of Cancer Cell-Based Vaccines for Glioblastoma Multiforme

Glioblastoma multiforme (GBM) is considered one of the most aggressive forms of brain cancer with a 15-month median survival, despite advancements in surgery, radiotherapy, and chemotherapy. The immune-suppressed tumor microenvironment and the blood-brain barrier are major contributors to its poor prognosis and treatment resistance. In the last decade, significant progress has been made in developing cell-based vaccines to boost immune responses against GBM. This review provides an extensive update on recent clinical trials involving various cancer cell vaccines, including ICT-107, the α-type-1 DC vaccine, and others. Although these trials have demonstrated potential improvements in progression-free survival (PFS) and overall survival (OS), the diverse and immune-suppressed nature of GBM poses challenges for consistent therapeutic success. We discuss the details of these trials along with the potential mechanism of vaccine efficacy and immune activations. The findings of these trials highlight the significance of a personalized immunotherapy approach and suggest that patient stratification could significantly advance the clinical management of GBM.

Surface display of two neoantigens on Lactiplantibacillus plantarum

Lactic acid bacteria, such as Lactiplantibacillus plantarum, are becoming increasingly popular hosts for combining production and delivery of therapeutic proteins to immune cells. Soluble antigens are susceptible to rapid proteolysis, hence anchoring of antigens to bacterial cells, which likely protects the antigen, is a preferred delivery strategy that may increase immune responses. In cancer research, personalized immunotherapy has high potential and, in this respect, the so-called neoantigens that accumulate in tumor cells are promising tumor specific targets. Here, we demonstrate that, when using the inducible pSIP expression system, L. plantarum can produce and surface display two neoantigens, NAG1 and ETV6. The antigens could be targeted to both the cell membrane and the cell wall, utilizing four different anchoring methods. The production level and the degree of surface exposure of the antigens varied among the anchors. Flow cytometry analysis showed that antigens anchored to the cell wall were more exposed than those anchored to the cell membrane. To our knowledge these are the first reports of neoantigens being produced and surface-displayed in Lactobacillales.

Integration of proteomics profiling data to facilitate discovery of cancer neoantigens: a survey

Cancer neoantigens are peptides that originate from alterations in the genome, transcriptome, or proteome. These peptides can elicit cancer-specific T-cell recognition, making them potential candidates for cancer vaccines. The rapid advancement of proteomics technology holds tremendous potential for identifying these neoantigens. Here, we provided an up-to-date survey about database-based search methods and de novo peptide sequencing approaches in proteomics, and we also compared these methods to recommend reliable analytical tools for neoantigen identification. Unlike previous surveys on mass spectrometry-based neoantigen discovery, this survey summarizes the key advancements in de novo peptide sequencing approaches that utilize artificial intelligence. From a comparative study on a dataset of the HepG2 cell line and nine mixed hepatocellular carcinoma proteomics samples, we demonstrated the potential of proteomics for the identification of cancer neoantigens and conducted comparisons of the existing methods to illustrate their limits. Understanding these limits, we suggested a novel workflow for neoantigen discovery as perspectives.

The potential applications of peptide-loading complex in cancer treatment

Immunotherapy for cancer has made significant strides in the last several years. The prognosis for cancer patients has significantly improved as a result, particularly in hematological diseases. However, it was discovered that translating these achievements to solid tumors proved challenging. The peptide-loading complex (PLC), a temporary multisubunit membrane assembly in the endoplasmic reticulum (ER), is crucial for initiating a hierarchical immune response. Chaperones calreticulin and tapasin make up the PLC, unique to class I glycoproteins, thiooxido-reductase ERp57, and a transporter associated with antigen processing. The loading and editing of major histocompatibility complex class I (MHC-I) molecules with peptide translocation into the ER are synchronized by the PLC. One of the immune escape strategies revealed for tumors so far is changes in the expression of MHC molecules. This is because MHC antigens are crucial in presenting antigens to T-lymphocytes and controlling NK cell activity. Furthermore, decreased MHC-I expression has been linked to malignancies resistant to T-cell-based cancer immunotherapies (adoptive transfer of antitumor CD8 T-cells or checkpoint inhibition). The PLC is essential for T-cell priming, differentiation, and tumor growth control because it can bind to a wide range of MHC-I allomorphs. In this review, we have looked into PLC's function and effects in all forms of cancer to improve cancer therapy techniques.

The immunopeptidome of colon cancer cells treated with topoisomerase inhibiting drug reveals differential as well as common endogenous protein sampling and display of MHC I-associated peptides

Immunotherapy options for microsatellite stable (MSS) colorectal cancer are currently very limited. The lack of detectably unique or altered immunogens in the tumor microenvironment may be a factor. Radiation and chemotherapy may enhance immunotherapy by increasing cancer cell visibility through Major Histocompatibility Complex I (MHC I) expression. To investigate this, we treated MSS and microsatellite-instable (MSI) colon cancer cells with a topoisomerase inhibitor and analyzed MHC I-associated peptides. Treatment increased peptide numbers by 5% in RKO (MSI) cells and 83% in SW620 (MSS) cells, with 40-50% of peptides being exclusive to treatment. Additionally, clustering analysis revealed a set of peptides with uniquely conserved residues displayed only in treated MSS SW620 cells. Gene Ontology analysis of MHC I-displayed proteins revealed a treatment-induced increase in extracellular vesicle- and nuclear-derived proteins, alongside reduced cytosolic protein sampling. Overall, we present evidence for treatment-inducible differential display of peptides, some of which may affect interactions and functions of immune cells. Given the multitude of factors that modulate the effects of increased MHC I expression and associated peptides, further studies are needed to elucidate the pathophysiological implications of these changes.

The potential impact of RNA splicing abnormalities on immune regulation in endometrial cancer

RNA splicing controls the post-transcriptional level of gene expression, allowing for the synthesis of many transcripts with various configurations and roles. Variations in RNA splicing regulatory factors, including splicing factors, signaling pathways, epigenetic modifications, and environmental factors, are typically the origin of tumor-associated splicing anomalies. Furthermore, thorough literature assessments on the intricate connection between tumor-related splicing dysregulation and tumor immunity are currently lacking. Therefore, we also thoroughly discuss putative targets associated with RNA splicing in endometrial cancer (EC) and the possible impacts of aberrant RNA splicing on the immune control of tumor cells and tumor microenvironment (TME), which contributes to enhancing the utilization of immunotherapy in the management of EC and offers an alternative viewpoint for the exploration of cancer therapies and plausible prognostic indicators.

Ancestral Differences in Anticancer Treatment Efficacy and Their Underlying Genomic and Molecular Alterations

SIGNIFICANCE

Our study charts a global landscape of ancestry-associated differences in therapeutic efficacy, highlighting the importance of considering ancestry in anticancer therapies.

Peptide‑based therapeutic strategies for glioma: Current state and prospects

Glioma is a prevalent form of primary malignant central nervous system tumor, characterized by its cellular invasiveness, rapid growth, and the presence of the blood-brain barrier (BBB)/blood-brain tumor barrier (BBTB). Current therapeutic approaches, such as chemotherapy and radiotherapy, have shown limited efficacy in achieving significant antitumor effects. Therefore, there is an urgent demand for new treatments. Therapeutic peptides represent an innovative class of pharmaceutical agents with lower immunogenicity and toxicity. They are easily modifiable via chemical means and possess deep tissue penetration capabilities which reduce side effects and drug resistance. These unique pharmacokinetic characteristics make peptides a rapidly growing class of new therapeutics that have demonstrated significant progress in glioma treatment. This review outlines the efforts and accomplishments in peptide-based therapeutic strategies for glioma. These therapeutic peptides can be classified into four types based on their anti-tumor function: tumor-homing peptides, inhibitor/antagonist peptides targeting cell surface receptors, interference peptides, and peptide vaccines. Furthermore, we briefly summarize the results from clinical trials of therapeutic peptides in glioma, which shows that peptide-based therapeutic strategies exhibit great potential as multifunctional players in glioma therapy.

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.

Modeling and simulation of genotypic Tumor Mutational Burden and Phenotypic Immunogenicity biomarkers in cancer immunoediting with Ising-Hamiltonian characterization

BACKGROUND AND OBJECTIVE

In the Tumor Micro-Environment, cancer progression and its relationship with the Immune System (IS) are described in terms of cancer immunoediting (CI) phases, each of which is characterized by different types and levels of interaction between the tumor cells and elements of the IS, such as CD8+T cells. Said interactions are governed by genotypical (Tumor Mutational Burden, TMB) and phenotypical aspects pertaining to the tumor, as well as by the strength of the IS. In this work, a computational model of CI is presented that incorporates the TMB and the biomarker Tumor Immunogenic Phenotype (TIP) as its control parameters, and which employs the Ising-model Hamiltonian to characterize the system with respect to the CI phases.

METHODS

Our model is a probabilistic multi-agent system with agents for tumor cells and for the IS. The computer implementation includes the parametrization of the TMB and the TIP, which is useful for identifying whether a tumor is hot or cold based on tumor immunogenicity and inflammation. For modeling the interactions between tumor and immune cells, the relevant elements are integrated under a Michaelis-Menten equation that regulates the recruitment rate of CD8+T cells and other IS elements. This novel quantification of immune cell recruitment encompasses the growth of neoantigen production, which in turn triggers the growth of CD8+T cells.

RESULTS

Our model reliably captures the Elimination, Equilibrium, and Escape phases of tumor-immune cell interactions, modulating the observed behaviors through the introduced parametrization of TMB and TIP biomarkers. Notably, these results align well with the combination of genotypical and phenotypical biomarkers analyzed in recent literature. A remarkable instance is the appreciable inhibition of the tumor activity during the Escape phase, observed for phenotypically hot tumors with relatively high TMB, and pointing towards improved efficacy of the IS against such tumors. The Ising-Hamiltonian provides precise quantification of diverse tumor-immune interactions across different TMB and TIP value combinations.

CONCLUSIONS

The presented model, formed by relatively simple agents, generates emergent behaviors through which the phases of CI are identified. The flexible choice of control parameters is robust enough and provides a plausible explanation for the mechanisms through which tumors with high TMB and high immunogenicity (i.e., hot tumors) exhibit a higher probability of responding to immunotherapy treatment. Characterization via the Ising-model Hamiltonian supports this explanation by summarizing the system's dynamics, which, in turn, facilitates its analysis and methodical improvements. The complex interplay of TMB, TIP, and individual physiology is finely captured.

Neoantigen Vaccines in Cancer Prevention

Recent advances in cancer immunotherapy have established neoantigen-based vaccines as a promising approach to cancer prevention. Unlike tumor-associated antigens, neoantigens originate exclusively from somatic mutations, thus enabling tumor-specific targeting without harm to normal tissues. This distinctive feature promotes robust immune responses while reducing the risk of autoimmune side effects. Developing standardized "off-the-shelf" vaccines targeting shared neoantigens offers a scalable strategy for cancer prevention, particularly benefitting genetically predisposed high-risk populations. These vaccines can be administered to high-risk individuals before malignant transformation to potentially intercept cancer development through early immune activation. Advances in next-generation sequencing and computational biology have increased the accuracy of neoantigen prediction, while advances in vaccine delivery platforms have boosted vaccine efficacy. The integration of neoantigen-based vaccines with immune checkpoint inhibitors, immune stimulants, and classic chemopreventive agents has a synergistic potential to improve cellular immunity. This review examines biological mechanisms, clinical development, and future directions of neoantigen-based vaccines in cancer prevention, emphasizing their clinical potential to revolutionize risk-reduction strategies.

The Landmark Series: Cancer Vaccines for Solid Tumors

Immunotherapy has become an integral part of the treatment for solid tumors. Cancer vaccines represent a potentially powerful class of immunotherapeutic agents to drive antitumor immunity. Cancer vaccine development involves selecting immunogenic target antigens expressed by tumor cells that can be effectively delivered for uptake by antigen-presenting cells to generate a robust adaptive immune response against tumor. While numerous cancer vaccines have been shown to produce antigen-specific immune responses, translating promising results of immunogenicity from early-phase trials into durable clinical benefit in larger randomized trials has remained elusive. Recent findings support new enthusiasm for several cancer vaccine approaches for solid tumors. This review will discuss landmark historic clinical trials in cancer vaccine development and strategies to optimize cancer vaccines to achieve improved clinical efficacy.

Tumour-infiltrating Lymphocytes and Radiation Therapy in Rectal Cancer: Systematic Review and Meta-analysis

AIM

Tumour-infiltrating lymphocytes (TILs) represent a promising cancer biomarker. Different TILs, including CD8+, CD4+, CD3+, and FOXP3+, have been associated with clinical outcomes. However, data are lacking regarding the value of TILs for patients receiving radiation therapy (RT). We conducted a systemic review and meta-analysis of available data evaluating TILs for patients receiving curative-intent therapy including RT.

MATERIALS AND METHODS

Eligible studies presented a defined cohort of patients who all received curative-intent therapy, including RT, and also reported the relationship between any TIL score and either tumour response or survival outcomes. After comprehensive search of online databases (PubMed, EMBASE, Cochrane, and Web of Science), 2 authors conducted title, abstract, and whole-text review for quality and risk of bias following Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Data from publications that met quality criteria were grouped via (1) TIL analysed, (2) pre- or post-RT TIL assessment, and (3) clinical outcome measured.

RESULTS

Initial search yielded 669 unique studies. Thirty-one studies met quality criteria, of which 20 studied rectal cancer (RC), 4 oesophageal, 3 pancreas, 2 lung, cervical/uterine 1 each. We conducted systematic review and meta-analysis of the RC publications. All except 2 were single-institutional cohort studies. After meta-analysis, the pre-RT epithelial CD8+ (p = 0.04) and stromal FOXP3+ (p = 0.01) counts were associated with survival without disease, while pre-RT epithelial (p = 0.02) and stromal (p = 0.001) FOXP3+ TILs were associated with overall survival. On post-RT analysis, epithelial (p = .04) and stromal (p = 0.02) CD8+ TILs were associated with survival without disease and epithelial CD8+ TILs were associated with overall survival (p = 0.01).Preoperative CD8+ and FOXP3+ TILs were generally associated with tumour response to RT, but meta-analysis was not conducted due to heterogeneity of response measurement techniques.

CONCLUSION

TILs represent a useful parameter for tumour response and survival outcomes for patients receiving curative-intent therapy, including RT for RC. Future work should aim to standardise TIL measurement and quantification methods and to develop protocols to clarify clinical application of these findings.

Development of CAR-T Therapies and Personalized Vaccines for the Treatment of Cholangiocarcinoma: Current Progress, Mechanisms of Action, and Challenges

Cholangiocarcinoma (CCA) is a highly fatal malignancy with an increasing prevalence, a high mortality rate, poor overall survival, and limited responsiveness to conventional chemoradiotherapy. Targeted therapies addressing specific gene mutations have expanded treatment options for some patient populations. The introduction of chimeric antigen receptor-modified T-cell (CAR-T) immunotherapy and personalized vaccines have opened up a new avenue for managing various cancers. Considerable efforts have been dedicated to preclinical research and ongoing clinical trials of immunotherapeutic approaches including CAR-T therapy, vaccines, and antibody-based therapies such as antibody drug conjugates. However, the potential of CAR-T therapy and vaccines in treating advanced unresectable/metastatic cholangiocarcinoma remains largely unexplored. This article offers an overview of the current landscape of antibody-based immunotherapy, particularly CAR-T therapy and vaccines in the context of cholangiocarcinoma treatment. It outlines a framework for selecting CAR-T and vaccine targets and delves into the biology of promising targetable antigens, as well as potential future therapeutic targets.

Multiple Classes of Antigen Contribute to the Antigenic Landscape of Mesothelioma

Mesothelioma is an incurable, asbestos-exposure-related cancer that typically affects the lining or pleura of the lungs. Symptoms typically develop many decades after initial asbestos exposure, leaving an enduring legacy of disease. The current disease burden is peaking worldwide and thus there is a massive unmet clinical need for curative therapies. Recently, immune checkpoint blockade-based therapy has been adopted as a first-line of treatment for mesothelioma. Vaccine-induced augmentation of immune responses unleashed during checkpoint blockade may provide further clinical benefit in mesothelioma. In this study, we explore the human leukocyte antigen class I landscape (or immunopeptidome) of mesothelioma in patient-derived cell lines and clinical material (pleural effusion samples). We identify a range of peptide antigens derived from targets including cancer testis antigens, endogenous retroviruses as well as novel post-translational modification of peptides. This information will facilitate the characterization of the immune response to these antigens to determine which class of antigen is most immunogenic and has the potential to be tested in future vaccine studies.

Vax-Innate: improving therapeutic cancer vaccines by modulating T cells and the tumour microenvironment

T cells have a critical role in mediating antitumour immunity. The success of immune checkpoint inhibitors (ICIs) for cancer treatment highlights how enhancing endogenous T cell responses can mediate tumour regression. However, mortality remains high for many cancers, especially in the metastatic setting. Based on advances in the genetic characterization of tumours and identification of tumour-specific antigens, individualized therapeutic cancer vaccines targeting mutated tumour antigens (neoantigens) are being developed to generate tumour-specific T cells for improved therapeutic responses. Early clinical trials using individualized neoantigen vaccines for patients with advanced disease had limited clinical efficacy despite demonstrated induction of T cell responses. Therefore, enhancing T cell activity by improving the magnitude, quality and breadth of T cell responses following vaccination is one current goal for improving outcome against metastatic tumours. Another major consideration is how T cells can be further optimized to function within the tumour microenvironment (TME). In this Perspective, we focus on neoantigen vaccines and propose a new approach, termed Vax-Innate, in which vaccination through intravenous delivery or in combination with tumour-targeting immune modulators may improve antitumour efficacy by simultaneously increasing the magnitude, quality and breadth of T cells while transforming the TME into a largely immunostimulatory environment for T cells.