Targeting neoantigens to augment antitumour immunity

Patient-specific vascularized tumor model: Blocking monocyte recruitment with multispecific antibodies targeting CCR2 and CSF-1R

Tumor-associated inflammation drives cancer progression and therapy resistance, often linked to the infiltration of monocyte-derived tumor-associated macrophages (TAMs), which are associated with poor prognosis in various cancers. To advance immunotherapies, testing on immunocompetent pre-clinical models of human tissue is crucial. We have developed an in vitro model of microvascular networks with tumor spheroids or patient tissues to assess monocyte trafficking into tumors and evaluate immunotherapies targeting the human tumor microenvironment. Our findings demonstrate that macrophages in vascularized breast and lung tumor models can enhance monocyte recruitment via CCL7 and CCL2, mediated by CSF-1R. Additionally, a multispecific antibody targeting CSF-1R, CCR2, and neutralizing TGF-β (CSF1R/CCR2/TGF-β Ab) repolarizes TAMs towards an anti-tumoral M1-like phenotype, reduces monocyte chemoattractant protein secretion, and blocks monocyte migration. This antibody also inhibits monocyte recruitment in patient-specific vascularized tumor models. In summary, this vascularized tumor model recapitulates the monocyte recruitment cascade, enabling functional testing of innovative therapeutic antibodies targeting TAMs in the tumor microenvironment.

Immunotherapy for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a major global healthcare challenge, with >1 million patients predicted to be affected annually by 2025. In contrast to other cancers, both incidence and mortality rates continue to rise, and HCC is now the third leading cause of cancer-related death worldwide. Immune checkpoint inhibitors (ICIs) have transformed the treatment landscape for advanced HCC, with trials demonstrating a superior overall survival benefit compared to sorafenib in the first-line setting. Combination therapy with either atezolizumab (anti-PD-L1) and bevacizumab (anti-VEGF) or durvalumab (anti-PD-L1) and tremelimumab (anti-CTLA-4) is now recognised as standard of care for advanced HCC. More recently, two phase III studies of ICI-based combination therapy in the early and intermediate disease settings have successfully met their primary end points of improved recurrence- and progression-free survival, respectively. Despite these advances, and in contrast to other tumour types, there remain no validated predictive biomarkers of response to ICIs in HCC. Ongoing research efforts are focused on further characterising the tumour microenvironment in order to select patients most likely to benefit from ICI and identify novel therapeutic targets. Herein, we review the current understanding of the immune landscape in which HCC develops and the evidence for ICI-based therapeutic strategies in HCC. Additionally, we describe the state of biomarker development and novel immunotherapy approaches in HCC which have progressed beyond the pre-clinical stage and into early-phase trials.

Crinophagic granules in pancreatic β cells contribute to mouse autoimmune diabetes by diversifying pathogenic epitope repertoire

Autoimmune attack toward pancreatic β cells causes permanent loss of glucose homeostasis in type 1 diabetes (T1D). Insulin secretory granules store and secrete insulin but are also thought to be tissue messengers for T1D. Here, we show that the crinophagic granules (crinosome), a minor set of vesicles formed by fusing lysosomes with the conventional insulin dense-core granules (DCG), are pathogenic in T1D development in mouse models. Pharmacological inhibition of crinosome formation in β cells delays T1D progression without affecting the dominant DCGs. Mechanistically, crinophagy inhibition diminishes the epitope repertoire in pancreatic islets, including cryptic, modified and disease-relevant epitopes derived from insulin. These unconventional insulin epitopes are largely undetectable in the MHC-II epitope repertoire of the thymus, where only canonical insulin epitopes are presented. CD4+ T cells targeting unconventional insulin epitopes display autoreactive phenotypes, unlike tolerized T cells recognizing epitopes presented in the thymus. Thus, the crinophagic pathway emerges as a tissue-intrinsic mechanism that transforms insulin from a signature thymic self-protein to a critical autoantigen by creating a peripheral-thymic mismatch in the epitope repertoire.

3D genome contributes to MHC-II neoantigen prediction

Reliable and ultra-fast DNA and RNA sequencing have been achieved with the emergence of high-throughput sequencing technology. When combining the results of DNA and RNA sequencing for tumor cells of cancer patients, neoantigens that potentially stimulate the immune response of either CD4+ or CD8+ T cells can be identified. However, due to the abundance of somatic mutations and the high polymorphic nature of human leukocyte antigen (HLA) it is challenging to accurately predict the neoantigens. Moreover, comparing to HLA-I presented peptides, the HLA-II presented peptides are more variable in length, making the prediction of HLA-II loaded neoantigens even harder. A number of computational approaches have been proposed to address this issue but none of them considers the DNA origin of the neoantigens from the perspective of 3D genome. Here we investigate the DNA origins of the immune-positive and non-negative HLA-II neoantigens in the context of 3D genome and discovered that the chromatin 3D architecture plays an important role in more effective HLA-II neoantigen prediction. We believe that the 3D genome information will help to increase the precision of HLA-II neoantigen discovery and eventually benefit precision and personalized medicine in cancer immunotherapy.

Glucosylated Nanovaccines for Dendritic Cell-Targeted Antigen Delivery and Amplified Cancer Immunotherapy

Engineering nanovaccines capable of targeting dendritic cells (DCs) is desperately required to maximize antigen cross-presentation to effector immune cells, elicit strong immune responses, and avoid adverse reactions. Here, we showed that glucose transporter 1 (Glut-1) on DCs is a reliable target for delivering antigens to DCs, and thus, a versatile antigen delivery strategy using glucosylated nanovaccines was developed for DC-targeted antigen delivery and tumor immunotherapy. The developed glucosylated ovalbumin-loaded nanovaccines highly accumulated in lymph nodes and efficiently engaged with Glut-1 on DCs to accelerate intracellular antigen delivery and promote DC maturation and antigen presentation, which elicited potent antitumor immunity to prevent and inhibit ovalbumin-expressing melanoma. Moreover, immunotherapeutic experiments in DC- and macrophage-depleted animal models confirmed that the glucosylated nanovaccines functioned mainly through DCs. In addition, the neoantigen-delivering glucosylated nanovaccines were further engineered to elicit tumor-specific immune responses against MC38 tumors. This study offers a DC-targeted antigen delivery strategy for cancer immunotherapy.

Epigenetic therapy potentiates transposable element transcription to create tumor-enriched antigens in glioblastoma cells

Inhibiting epigenetic modulators can transcriptionally reactivate transposable elements (TEs). These TE transcripts often generate unique peptides that can serve as immunogenic antigens for immunotherapy. Here, we ask whether TEs activated by epigenetic therapy could appreciably increase the antigen repertoire in glioblastoma, an aggressive brain cancer with low mutation and neoantigen burden. We treated patient-derived primary glioblastoma stem cell lines, an astrocyte cell line and primary fibroblast cell lines with epigenetic drugs, and identified treatment-induced, TE-derived transcripts that are preferentially expressed in cancer cells. We verified that these transcripts could produce human leukocyte antigen class I-presented antigens using liquid chromatography with tandem mass spectrometry pulldown experiments. Importantly, many TEs were also transcribed, even in proliferating nontumor cell lines, after epigenetic therapy, which suggests that targeted strategies like CRISPR-mediated activation could minimize potential side effects of activating unwanted genomic regions. The results highlight both the need for caution and the promise of future translational efforts in harnessing treatment-induced TE-derived antigens for targeted immunotherapy.

Merkel Cell Polyomavirus-Pathophysiology and Treatment in the Era of Gene-Targeted Therapies

Merkel cell polyomavirus (MCPyV) is a significant contributor to the development of Merkel cell carcinoma (MCC), an aggressive skin cancer with high recurrence and a low survival rate. In fact, it is the deadliest skin cancer. The precise routes of transmission for MCPyV-positive MCC remain unclear, but several factors may trigger its development. Conventional treatments for MCC are not highly effective, especially in patients with metastasis, with a clear need for new treatment options. Gene-targeted therapies hold great promise for the treatment of MCC, including the use of siRNA and CRISPR/Cas (C/Cas) but critically none have yet been translated into clinical trials. Validating this approach is the fact that several siRNA products are already FDA licenced, while C/Cas has entered clinical trial, albeit for conditions other than MCC. There are many challenges that must be overcome to move from preclinical research to the clinic. In this review, we provide a comprehensive summary of the current understanding of MCC, with a particular focus on MCPyV-positive MCC, and the status of gene-targeted therapies. Additionally, we discuss the major obstacles that impede MCC research and explore future prospects.

Immunotherapies targeting the oncogenic fusion gene CLDN18-ARHGAP in gastric cancer

The CLDN18-ARHGAP fusion gene is an oncogenic driver newly discovered in gastric cancer. It was detected in 9% (8/87) of gastric cancer patients in our center. An immunogenic peptide specifically targeting CLDN18-ARHGAP fusion gene was generated to induce neoantigen-reactive T cells, which was proved to have specific and robust anti-tumor capacity both in in vitro coculture models and in vivo xenograft gastric cancer models. Apart from the immunogenic potential, CLDN18-ARHGAP fusion gene was also found to contribute to immune suppression by inducing a regulatory T (Treg) cell-enriched microenvironment. Mechanistically, gastric cancer cells with CLDN18-ARHGAP fusion activate PI3K/AKT-mTOR-FAS signaling, which enhances free fatty acid production of gastric cancer cells to favor the survival of Treg cells. Furthermore, PI3K inhibition could effectively reverse Treg cells upregulation to enhance anti-tumor cytotoxicity of neoantigen-reactive T cells in vitro and reduce tumor growth in the xenograft gastric cancer model. Our study identified the CLDN18-ARHGAP fusion gene as a critical source of immunogenic neoepitopes, a key regulator of the tumor immune microenvironment, and immunotherapeutic applications specific to this oncogenic fusion.

Developing Vaccines in Pancreatic Adenocarcinoma: Trials and Tribulations

Pancreatic adenocarcinoma represents one of the most challenging malignancies to treat, with dismal survival rates despite advances in therapeutic modalities. Immunotherapy, particularly vaccines, has emerged as a promising strategy to harness the body's immune system in combating this aggressive cancer. This abstract reviews the trials and tribulations encountered in the development of vaccines targeting pancreatic adenocarcinoma. Key challenges include the immunosuppressive tumor microenvironment, the heterogeneity of tumor antigens, and a limited understanding of immune evasion mechanisms employed by pancreatic cancer cells. Various vaccine platforms, including peptide-based, dendritic cell-based, and viral vector-based vaccines, have been explored in preclinical and clinical settings. However, translating promising results from preclinical models to clinical efficacy has proven elusive. In recent years, mRNA vaccines have emerged as a promising immunotherapeutic strategy in the fight against various cancers, including pancreatic adenocarcinoma. We will discuss the potential applications, opportunities, and challenges associated with mRNA vaccines in pancreatic cancer treatment.

Advances in the study of LNPs for mRNA delivery and clinical applications

Messenger ribonucleic acid (mRNA) was discovered in 1961 as an intermediary for transferring genetic information from DNA to ribosomes for protein synthesis. The COVID-19 pandemic brought worldwide attention to mRNA vaccines. The emergency use authorization of two COVID-19 mRNA vaccines, BNT162b2 and mRNA-1273, were major achievements in the history of vaccine development. Lipid nanoparticles (LNPs), one of the most superior non-viral delivery vectors available, have made many exciting advances in clinical translation as part of the COVID-19 vaccine and therefore has the potential to accelerate the clinical translation of many gene drugs. In addition, due to these small size, biocompatibility and excellent biodegradability, LNPs can efficiently deliver nucleic acids into cells, which is particularly important for current mRNA therapeutic regimens. LNPs are composed cationic or pH-dependent ionizable lipid bilayer, polyethylene glycol (PEG), phospholipids, and cholesterol, represents an advanced system for the delivery of mRNA vaccines. Furthermore, optimization of these four components constituting the LNPs have demonstrated enhanced vaccine efficacy and diminished adverse effects. The incorporation of biodegradable lipids enhance the biocompatibility of LNPs, thereby improving its potential as an efficacious therapeutic approach for a wide range of challenging and intricate diseases, encompassing infectious diseases, liver disorders, cancer, cardiovascular diseases, cerebrovascular conditions, among others. Consequently, this review aims to furnish the scientific community with the most up-to-date information regarding mRNA vaccines and LNP delivery systems.

Neoantigen landscape supports feasibility of personalized cancer vaccine for follicular lymphoma

ABSTRACT

Personalized cancer vaccines designed to target neoantigens represent a promising new treatment paradigm in oncology. In contrast to classical idiotype vaccines, we hypothesized that "polyvalent" vaccines could be engineered for the personalized treatment of follicular lymphoma (FL) using neoantigen discovery by combined whole-exome sequencing (WES) and RNA sequencing (RNA-seq). Fifty-eight tumor samples from 57 patients with FL underwent WES and RNA-seq. Somatic and B-cell clonotype neoantigens were predicted and filtered to identify high-quality neoantigens. B-cell clonality was determined by the alignment of B-cell receptor (BCR) CDR3 regions from RNA-seq data, grouping at the protein level, and comparison with the BCR repertoire from healthy individuals using RNA-seq data. An average of 52 somatic mutations per patient (range, 2-172) were identified, and ≥2 (median, 15) high-quality neoantigens were predicted for 56 of 58 FL samples. The predicted neoantigen peptides were composed of missense mutations (77%), indels (9%), gene fusions (3%), and BCR sequences (11%). Building off of these preclinical analyses, we initiated a pilot clinical trial using personalized neoantigen vaccination combined with PD-1 blockade in patients with relapsed or refractory FL (#NCT03121677). Synthetic long peptide vaccines targeting predicted high-quality neoantigens were successfully synthesized for and administered to all 4 patients enrolled. Initial results demonstrate feasibility, safety, and potential immunologic and clinical responses. Our study suggests that a genomics-driven personalized cancer vaccine strategy is feasible for patients with FL, and this may overcome prior challenges in the field. This trial was registered at www.ClinicalTrials.gov as #NCT03121677.

Unlocking the potential of bispecific ADCs for targeted cancer therapy

Antibody-drug conjugates (ADCs) are biologically targeted drugs composed of antibodies and cytotoxic drugs connected by linkers. These innovative compounds enable precise drug delivery to tumor cells, minimizing harm to normal tissues and offering excellent prospects for cancer treatment. However, monoclonal antibody-based ADCs still present challenges, especially in terms of balancing efficacy and safety. Bispecific antibodies are alternatives to monoclonal antibodies and exhibit superior internalization and selectivity, producing ADCs with increased safety and therapeutic efficacy. In this review, we present available evidence and future prospects regarding the use of bispecific ADCs for cancer treatment, including a comprehensive overview of bispecific ADCs that are currently in clinical trials. We offer insights into the future development of bispecific ADCs to provide novel strategies for cancer treatment.

Enhancing in situ cancer vaccines using delivery technologies

In situ cancer vaccination refers to any approach that exploits tumour antigens available at a tumour site to induce tumour-specific adaptive immune responses. These approaches hold great promise for the treatment of many solid tumours, with numerous candidate drugs under preclinical or clinical evaluation and several products already approved. However, there are challenges in the development of effective in situ cancer vaccines. For example, inadequate release of tumour antigens from tumour cells limits antigen uptake by immune cells; insufficient antigen processing by antigen-presenting cells restricts the generation of antigen-specific T cell responses; and the suppressive immune microenvironment of the tumour leads to exhaustion and death of effector cells. Rationally designed delivery technologies such as lipid nanoparticles, hydrogels, scaffolds and polymeric nanoparticles are uniquely suited to overcome these challenges through the targeted delivery of therapeutics to tumour cells, immune cells or the extracellular matrix. Here, we discuss delivery technologies that have the potential to reduce various clinical barriers for in situ cancer vaccines. We also provide our perspective on this emerging field that lies at the interface of cancer vaccine biology and delivery technologies.

Unveiling the role of AGT in lipid metabolism and regulated cell death in colon cancer

BACKGROUND

Lipid metabolism and regulated cell death (RCD) play a role in the remodeling of tumor immune microenvironment and regulation of cancer progression. Since the underlying immune mechanisms of colon cancer remain elusive, this study aims to identify potential therapeutic target genes.

METHODS

Differential genes related to lipid metabolism and RCD in COAD patients were identified using R language and online tools. Based on the expression of genes, two groups were classified using consensus clustering. CIBERSORT and ssGSEA were used to detect immune infiltration in both groups. Prognostic signature genes for colon cancer were screened using machine learning algorithms. KEGG, GO and GSEA for gene pathway enrichment. In addition, interacting genes in the immune module were obtained using a weighted gene co-expression network (WGCNA). Finally, expression and mutation of key in colon cancer genes were detected using TIMER, HPR, cBioPortal website and qPCR.

RESULTS

The consensus clustering analysis revealed that 231 relevant differential genes were highly associated with immune infiltration. A series of machine learning and website analyses identified AGT as a hub gene linked to lipid metabolism and regulated cell death, which is overexpressed in colon cancer.

CONCLUSION

AGT, as a signature gene of lipid metabolism and regulated cell death, plays a critical role in the development of COAD and is associated with tumor immune infiltration.

Inhibition of DNMTs increases neoantigen-reactive T-cell toxicity against microsatellite-stable colorectal cancer in combination with radiotherapy

The therapeutic efficacy of immunotherapy is limited in the majority of colorectal cancer patients due to the low mutational and neoantigen burdens in this immunogenically "cold" microsatellite stability-colorectal cancer (MSS-CRC) cohort. Here, we showed that DNA methyltransferase (DNMT) inhibition upregulated neoantigen-bearing gene expression in MSS-CRC, resulting in increased neoantigen presentation by MHC class I in tumor cells and leading to increased neoantigen-specific T-cell activation in combination with radiotherapy. The cytotoxicity of neoantigen-reactive T cells (NRTs) to DNMTi-treated cancer cells was highly cytotoxic, and these cells secreted high IFNγ levels targeting MSS-CRC cells after ex vivo expansion of NRTs with DNMTi-treated tumor antigens. Moreover, the therapeutic efficacy of NRTs further increased when NRTs were combined with radiotherapy in vivo. Administration of DNMTi-augmented NRTs and radiotherapy achieved an ∼50 % complete response and extended survival time in an immunocompetent MSS-CRC animal model. Moreover, remarkably, splenocytes from these mice exhibited neoantigen-specific T-cell responses, indicating that radiotherapy in combination with DNMTi-augmented NRTs prolonged and increased neoantigen-specific T-cell toxicity in MSS-CRC patients. In addition, these DNMTi-augmented NRTs markedly increase the therapeutic efficacy of cancer vaccines and immune checkpoint inhibitors (ICIs). These data suggest that a combination of radiotherapy and epi-immunotherapeutic agents improves the function of ex vivo-expanded neoantigen-reactive T cells and increases the tumor-specific cytotoxic effector population to enhance therapeutic efficacy in MSS-CRC.

Vaccine a promising immunotherapy option for head and neck cancer patients

Head and neck cancer (HNC) is a diversified group of tumors arising from the upper aerodigestive tract, encompassing the oral cavity, larynx, and pharynx. Globally, this particular cancer ranks sixth in prevalence, resulting in an annual mortality rate above 325,000 individuals. Surgery, radiation, and chemotherapy are the primary therapeutic options for HNC, which are frequently used in combination. Despite their extensive use, these treatments are typically unsuccessful and can significantly impair patient quality of life. Therapeutic vaccinations are administered to cancer patients instead of preventative immunizations administered to a healthy population. The efficacy of this modality has considerably transformed the application and success of cancer management by providing an additional and effective therapeutic option for patients. Cancer treatment has been revolutionized by introducing Immune Checkpoint receptors inhibitors (ICR), such as anti-CTLA4, anti-PD-1, and anti-PD-L1.3. ICR have also established immunity against self-generated cancerous cells. Cancer vaccines have shown extraordinary synergistic potential with checkpoint inhibitors to maximize tumor-specific CD8+ expansion and activity, which detects and destroys tumor cells. Personalized neoantigen vaccination therapies can potentially combat the heterogeneity of each patient's tumor. The findings of this review suggest that recent advances in cancer immunology and genetics imply that cancer vaccination can be a promising alternative treatment for head and neck cancer patients. This review conducted a comprehensive literature search to identify relevant studies on immunotherapy options for head and neck cancer patients. The search strategy was designed to capture a wide range of peer-reviewed articles, conference proceedings, and grey literature from 2013 to 2023. The databases searched to ensure comprehensive coverage of the literature included PubMed, Web of Science, and Google Scholar; to include grey literature and articles not indexed in traditional databases.

The bright side of chemistry: Exploring synthetic peptide-based anticancer vaccines

The present review focuses on synthetic peptide-based vaccine strategies in the context of anticancer intervention, paying attention to critical aspects such as peptide epitope selection, adjuvant integration, and nuanced classification of synthetic peptide cancer vaccines. Within this discussion, we delve into the diverse array of synthetic peptide-based anticancer vaccines, each derived from tumor-associated antigens (TAAs), including melanoma antigen recognized by T cells 1 (Melan-A or MART-1), mucin 1 (MUC1), human epidermal growth factor receptor 2 (HER-2), tumor protein 53 (p53), human telomerase reverse transcriptase (hTERT), survivin, folate receptor (FR), cancer-testis antigen 1 (NY-ESO-1), and prostate-specific antigen (PSA). We also describe the synthetic peptide-based vaccines developed for cancers triggered by oncovirus, such as human papillomavirus (HPV), and hepatitis C virus (HCV). Additionally, the potential synergy of peptide-based vaccines with common therapeutics in cancer was considered. The last part of our discussion deals with the realm of the peptide-based vaccines delivery, highlighting its role in translating the most promising candidates into effective clinical strategies. Although this discussion does not cover all the ongoing peptide vaccine investigations, it aims at offering valuable insights into the chemical modifications and the structural complexities of anticancer peptide-based vaccines.

Bispecific and multispecific antibodies in oncology: opportunities and challenges

Research into bispecific antibodies, which are designed to simultaneously bind two antigens or epitopes, has advanced enormously over the past two decades. Owing to advances in protein engineering technologies and considerable preclinical research efforts, bispecific antibodies are constantly being developed and optimized to improve their efficacy and to mitigate toxicity. To date, >200 of these agents, the majority of which are bispecific immune cell engagers, are in either preclinical or clinical evaluation. In this Review, we discuss the role of bispecific antibodies in patients with cancer, including history and development, as well as innovative targeting strategies, clinical applications, and adverse events. We also discuss novel alternative bispecific antibody constructs, such as those targeting two antigens expressed by tumour cells or cells located in the tumour microenvironment. Finally, we consider future research directions in this rapidly evolving field, including innovative antibody engineering strategies, which might enable more effective delivery, overcome resistance, and thus optimize clinical outcomes.

Development and Clinical Applications of Therapeutic Cancer Vaccines with Individualized and Shared Neoantigens

Neoantigens, presented as peptides on the surfaces of cancer cells, have recently been proposed as optimal targets for immunotherapy in clinical practice. The promising outcomes of neoantigen-based cancer vaccines have inspired enthusiasm for their broader clinical applications. However, the individualized tumor-specific antigens (TSA) entail considerable costs and time due to the variable immunogenicity and response rates of these neoantigens-based vaccines, influenced by factors such as neoantigen response, vaccine types, and combination therapy. Given the crucial role of neoantigen efficacy, a number of bioinformatics algorithms and pipelines have been developed to improve the accuracy rate of prediction through considering a series of factors involving in HLA-peptide-TCR complex formation, including peptide presentation, HLA-peptide affinity, and TCR recognition. On the other hand, shared neoantigens, originating from driver mutations at hot mutation spots (e.g., KRASG12D), offer a promising and ideal target for the development of therapeutic cancer vaccines. A series of clinical practices have established the efficacy of these vaccines in patients with distinct HLA haplotypes. Moreover, increasing evidence demonstrated that a combination of tumor associated antigens (TAAs) and neoantigens can also improve the prognosis, thus expand the repertoire of shared neoantigens for cancer vaccines. In this review, we provide an overview of the complex process involved in identifying personalized neoantigens, their clinical applications, advances in vaccine technology, and explore the therapeutic potential of shared neoantigen strategies.

Association between tertiary lymphoid structures and clinical outcomes in cancer patients treated with immune checkpoint inhibitors: an updated meta-analysis

Background

Although numerous studies have reported the association between tertiary lymphoid structures (TLSs) and clinical outcomes in cancer patients treated with immune checkpoint inhibitors (ICIs), there remains a lack of a newer and more comprehensive meta-analysis. The main objective of this study is to explore prognostic biomarkers in immunotherapy-related patients, through analyzing the associations between tertiary lymphoid structures (TLSs) and clinical outcomes in cancer patients treated with ICIs, so as to investigate their prognostic value in cancer patients treated with ICIs.

Methods

A comprehensive search was conducted until February 2024 across PubMed, Embase, Web of Science, and the Cochrane Library databases to identify relevant studies evaluating the association between tertiary lymphoid structures and clinical outcomes in cancer patients treated with ICIs. The clinical outcomes were overall survival (OS), progression-free survival (PFS), and objective response rate (ORR).

Results

Thirteen studies were incorporated in this meta-analysis, among which nine evaluated the prognostic value of TLSs. The results showed the high levels of TLSs predicted a significantly prolonged OS (pooled HR = 0.35, 95% CI: 0.24-0.53, p < 0.001) and PFS (pooled HR = 0.47, 95% CI: 0.31-0.72, p < 0.001), while lower ORR (pooled OR = 3.78, 95% CI: 2.26-6.33, p < 0.001) in cancer patients treated with ICIs.

Conclusion

Our results indicated that high levels of TLSs could predict a favorable prognosis for cancer patients treated with ICIs and have the potential to become a prognostic biomarker of immunotherapy-related patients.

Frequency-dependent selection of neoantigens fosters tumor immune escape and predicts immunotherapy response

Cancer is an evolutionary process shaped by selective pressure from the microenvironments. However, recent studies reveal that certain tumors undergo neutral evolution where there is no detectable fitness difference amongst the cells following malignant transformation. Here, through computational modeling, we demonstrate that negative frequency-dependent selection (or NFDS), where the immune response against cancer cells depends on the clonality of neoantigens, can lead to an immunogenic landscape that is highly similar to neutral evolution. Crucially, NFDS promotes high antigenic heterogeneity and early immune evasion in hypermutable tumors, leading to poor responses to immune checkpoint blockade (ICB) therapy. Our model also reveals that NFDS is characterized by a negative association between average clonality and total burden of neoantigens. Indeed, this unique feature of NFDS is common in the whole-exome sequencing (WES) datasets (357 tumor samples from 275 patients) from four melanoma cohorts with ICB therapy and a non-small cell lung cancer (NSCLC) WES dataset (327 tumor samples from 100 patients). Altogether, our study provides quantitative evidence supporting the theory of NFDS in cancer, explaining the high prevalence of neutral-looking tumors. These findings also highlight the critical role of frequency-dependent selection in devising more efficient and predictive immunotherapies.

Tumor initiation and early tumorigenesis: molecular mechanisms and interventional targets

Tumorigenesis is a multistep process, with oncogenic mutations in a normal cell conferring clonal advantage as the initial event. However, despite pervasive somatic mutations and clonal expansion in normal tissues, their transformation into cancer remains a rare event, indicating the presence of additional driver events for progression to an irreversible, highly heterogeneous, and invasive lesion. Recently, researchers are emphasizing the mechanisms of environmental tumor risk factors and epigenetic alterations that are profoundly influencing early clonal expansion and malignant evolution, independently of inducing mutations. Additionally, clonal evolution in tumorigenesis reflects a multifaceted interplay between cell-intrinsic identities and various cell-extrinsic factors that exert selective pressures to either restrain uncontrolled proliferation or allow specific clones to progress into tumors. However, the mechanisms by which driver events induce both intrinsic cellular competency and remodel environmental stress to facilitate malignant transformation are not fully understood. In this review, we summarize the genetic, epigenetic, and external driver events, and their effects on the co-evolution of the transformed cells and their ecosystem during tumor initiation and early malignant evolution. A deeper understanding of the earliest molecular events holds promise for translational applications, predicting individuals at high-risk of tumor and developing strategies to intercept malignant transformation.

The effect of smoking on tumor immunoediting: Friend or foe?

The recognition of smoking as an independent risk factor for lung cancer has become a widely accepted within the realm of respiratory medicine. The emergence of tumor immunotherapy has notably enhanced the prognosis for numerous late-stage cancer patients. Nevertheless, some studies have noted a tendency for lung cancer patients who smoke to derive greater benefit from immunotherapy. This observation has sparked increased interest in the interaction between smoking and the immune response to tumors in lung cancer. The concept of cancer immunoediting has shed light on the intricate and nuanced relationship between the immune system and tumors. Starting from the perspectives of immune surveillance, immune equilibrium, and immune evasion, this narrative review explores how smoking undermines the immune response against tumor cells and induces the generation of tumor neoantigens, and examines other behaviors that trigger tumor immune evasion. By elucidating these aspects, the review concludes that smoking is not conducive to tumor immunoediting.

Phase I Trial of Viral Vector-Based Personalized Vaccination Elicits Robust Neoantigen-Specific Antitumor T-Cell Responses

PURPOSE

Personalized vaccines targeting multiple neoantigens (nAgs) are a promising strategy for eliciting a diversified antitumor T-cell response to overcome tumor heterogeneity. NOUS-PEV is a vector-based personalized vaccine, expressing 60 nAgs and consists of priming with a nonhuman Great Ape Adenoviral vector (GAd20) followed by boosts with Modified Vaccinia Ankara. Here, we report data of a phase Ib trial of NOUS-PEV in combination with pembrolizumab in treatment-naïve patients with metastatic melanoma (NCT04990479).

PATIENTS AND METHODS

The feasibility of this approach was demonstrated by producing, releasing, and administering to 6 patients 11 of 12 vaccines within 8 weeks from biopsy collection to GAd20 administration.

RESULTS

The regimen was safe, with no treatment-related serious adverse events observed and mild vaccine-related reactions. Vaccine immunogenicity was demonstrated in all evaluable patients receiving the prime/boost regimen, with detection of robust neoantigen-specific immune responses to multiple neoantigens comprising both CD4 and CD8 T cells. Expansion and diversification of vaccine-induced T-cell receptor (TCR) clonotypes was observed in the posttreatment biopsies of patients with clinical response, providing evidence of tumor infiltration by vaccine-induced neoantigen-specific T cells.

CONCLUSIONS

These findings indicate the ability of NOUS-PEV to amplify and broaden the repertoire of tumor-reactive T cells to empower a diverse, potent, and durable antitumor immune response. Finally, a gene signature indicative of the reduced presence of activated T cells together with very poor expression of the antigen-processing machinery genes has been identified in pretreatment biopsies as a potential biomarker of resistance to the treatment.

Neoantigen-specific stimulation of tumor-infiltrating lymphocytes enables effective TCR isolation and expansion while preserving stem-like memory phenotypes

BACKGROUND

Tumor-infiltrating lymphocytes (TILs) targeting neoantigens can effectively treat a selected set of metastatic solid cancers. However, harnessing TILs for cancer treatments remains challenging because neoantigen-reactive T cells are often rare and exhausted, and ex vivo expansion can further reduce their frequencies. This complicates the identification of neoantigen-reactive T-cell receptors (TCRs) and the development of TIL products with high reactivity for patient treatment.

METHODS

We tested whether TILs could be in vitro stimulated against neoantigens to achieve selective expansion of neoantigen-reactive TILs. Given their prevalence, mutant p53 or RAS were studied as models of human neoantigens. An in vitro stimulation method, termed "NeoExpand", was developed to provide neoantigen-specific stimulation to TILs. 25 consecutive patient TILs from tumors harboring p53 or RAS mutations were subjected to NeoExpand.

RESULTS

We show that neoantigenic stimulation achieved selective expansion of neoantigen-reactive TILs and broadened the neoantigen-reactive CD4+ and CD8+ TIL clonal repertoire. This allowed the effective isolation of novel neoantigen-reactive TCRs. Out of the 25 consecutive TIL samples, neoantigenic stimulation enabled the identification of 16 unique reactivities and 42 TCRs, while conventional TIL expansion identified 9 reactivities and 14 TCRs. Single-cell transcriptome analysis revealed that neoantigenic stimulation increased neoantigen-reactive TILs with stem-like memory phenotypes expressing IL-7R, CD62L, and KLF2. Furthermore, neoantigenic stimulation improved the in vivo antitumor efficacy of TILs relative to the conventional OKT3-induced rapid TIL expansion in p53-mutated or KRAS-mutated xenograft mouse models.

CONCLUSIONS

Taken together, neoantigenic stimulation of TILs selectively expands neoantigen-reactive TILs by frequencies and by their clonal repertoire. NeoExpand led to improved phenotypes and functions of neoantigen-reactive TILs. Our data warrant its clinical evaluation.

TRIAL REGISTRATION NUMBER

NCT00068003, NCT01174121, and NCT03412877.

Cancer biotherapy: review and prospect

Malignant tumors pose a grave threat to the quality of human life. The prevalence of malignant tumors in China is steadily rising. Presently, clinical interventions encompass surgery, radiotherapy, and pharmaceutical therapy in isolation or combination. Nonetheless, these modalities fail to completely eradicate malignant tumor cells, frequently leading to metastasis and recurrence. Conversely, tumor biotherapy has emerged as an encouraging fourth approach in preventing and managing malignant tumors owing to its safety, efficacy, and minimal adverse effects. Currently, a range of tumor biotherapy techniques are employed, including gene therapy, tumor vaccines, monoclonal antibody therapy, cancer stem cell therapy, cytokine therapy, and adoptive cellular immunotherapy. This study aims to comprehensively review the latest developments in biological treatments for malignant tumors.

Comprehensive profiling of cancer neoantigens from aberrant RNA splicing

BACKGROUND

Cancer neoantigens arise from protein-altering somatic mutations in tumor and rank among the most promising next-generation immuno-oncology agents when used in combination with immune checkpoint inhibitors. We previously developed a computational framework, REAL-neo, for identification, quality control, and prioritization of both class-I and class-II human leucocyte antigen (HLA)-presented neoantigens resulting from somatic single-nucleotide mutations, small insertions and deletions, and gene fusions. In this study, we developed a new module, SPLICE-neo, to identify neoantigens from aberrant RNA transcripts from two distinct sources: (1) DNA mutations within splice sites and (2) de novo RNA aberrant splicings.

METHODS

First, SPLICE-neo was used to profile all DNA splice-site mutations in 11,892 tumors from The Cancer Genome Atlas (TCGA) and identified 11 profiles of splicing donor or acceptor site gains or losses. Transcript isoforms resulting from the top seven most frequent profiles were computed using novel logic models. Second, SPLICE-neo identified de novo RNA splicing events using RNA sequencing reads mapped to novel exon junctions from either single, double, or multiple exon-skipping events. The aberrant transcripts from both sources were then ranked based on isoform expression levels and z-scores assuming that individual aberrant splicing events are rare. Finally, top-ranked novel isoforms were translated into protein, and the resulting neoepitopes were evaluated for neoantigen potential using REAL-neo. The top splicing neoantigen candidates binding to HLA-A*02:01 were validated using in vitro T2 binding assays.

RESULTS

We identified abundant splicing neoantigens in four representative TCGA cancers: BRCA, LUAD, LUSC, and LIHC. In addition to their substantial contribution to neoantigen load, several splicing neoantigens were potent tumor antigens with stronger bindings to HLA compared with the positive control of antigens from influenza virus.

CONCLUSIONS

SPLICE-neo is the first tool to comprehensively identify and prioritize splicing neoantigens from both DNA splice-site mutations and de novo RNA aberrant splicings. There are two major advances of SPLICE-neo. First, we developed novel logic models that assemble and prioritize full-length aberrant transcripts from DNA splice-site mutations. Second, SPLICE-neo can identify exon-skipping events involving more than two exons, which account for a quarter to one-third of all skipping events.

Current Trends in Vaccine Development for Hereditary Colorectal Cancer Syndromes

The coming of age for cancer treatment has experienced exponential growth in the last decade with the addition of immunotherapy as the fourth pillar to the fundamentals of cancer treatment-chemotherapy, surgery, and radiation-taking oncology to an astounding new frontier. In this time, rapid developments in computational biology coupled with immunology have led to the exploration of priming the host immune system through vaccination to prevent and treat certain subsets of cancer such as melanoma and hereditary colorectal cancer. By targeting the immune system through tumor-specific antigens-namely, neoantigens (neoAgs)-the future of cancer prevention may lie within arm's reach by employing neoAg vaccines as an immune-preventive modality for hereditary cancer syndromes like Lynch syndrome. In this review, we discuss the history, current trends, utilization, and future direction of neoAg-based vaccines in the setting of hereditary colorectal cancer.

Facts and Hopes in Using Omics to Advance Combined Immunotherapy Strategies

The field of oncology has been transformed by immune checkpoint inhibitors (ICI) and other immune-based agents; however, many patients do not receive a durable benefit. While biomarker assessments from pivotal ICI trials have uncovered certain mechanisms of resistance, results thus far have only scraped the surface. Mechanisms of resistance are as complex as the tumor microenvironment (TME) itself, and the development of effective therapeutic strategies will only be possible by building accurate models of the tumor-immune interface. With advancement of multi-omic technologies, high-resolution characterization of the TME is now possible. In addition to sequencing of bulk tumor, single-cell transcriptomic, proteomic, and epigenomic data as well as T-cell receptor profiling can now be simultaneously measured and compared between responders and nonresponders to ICI. Spatial sequencing and imaging platforms have further expanded the dimensionality of existing technologies. Rapid advancements in computation and data sharing strategies enable development of biologically interpretable machine learning models to integrate data from high-resolution, multi-omic platforms. These models catalyze the identification of resistance mechanisms and predictors of benefit in ICI-treated patients, providing scientific foundation for novel clinical trials. Moving forward, we propose a framework by which in silico screening, functional validation, and clinical trial biomarker assessment can be used for the advancement of combined immunotherapy strategies.

Regulatory T cell-mediated immunosuppression orchestrated by cancer: towards an immuno-genomic paradigm for precision medicine

Accumulating evidence indicates that aberrant signalling stemming from genetic abnormalities in cancer cells has a fundamental role in their evasion of antitumour immunity. Immune escape mechanisms include enhanced expression of immunosuppressive molecules, such as immune-checkpoint proteins, and the accumulation of immunosuppressive cells, including regulatory T (Treg) cells, in the tumour microenvironment. Therefore, Treg cells are key targets for cancer immunotherapy. Given that therapies targeting molecules predominantly expressed by Treg cells, such as CD25 or GITR, have thus far had limited antitumour efficacy, elucidating how certain characteristics of cancer, particularly genetic abnormalities, influence Treg cells is necessary to develop novel immunotherapeutic strategies. Hence, Treg cell-targeted strategies based on the particular characteristics of cancer in each patient, such as the combination of immune-checkpoint inhibitors with molecularly targeted agents that disrupt the immunosuppressive networks mediating Treg cell recruitment and/or activation, could become a new paradigm of cancer therapy. In this Review, we discuss new insights on the mechanisms by which cancers generate immunosuppressive networks that attenuate antitumour immunity and how these networks confer resistance to cancer immunotherapy, with a focus on Treg cells. These insights lead us to propose the concept of 'immuno-genomic precision medicine' based on specific characteristics of cancer, especially genetic profiles, that correlate with particular mechanisms of tumour immune escape and might, therefore, inform the optimal choice of immunotherapy for individual patients.

CD8+ T cell-based cancer immunotherapy

The immune system in humans is a defense department against both exogenous and endogenous hazards, where CD8+ T cells play a crucial role in opposing pathological threats. Various immunotherapies based on CD8+ T cells have emerged in recent decades, showing their promising results in treating intractable diseases. However, in the fight against the constantly changing and evolving cancers, the formation and function of CD8+ T cells can be challenged by tumors that might train a group of accomplices to resist the T cell killing. As cancer therapy stepped into the era of immunotherapy, understanding the physiological role of CD8+ T cells, studying the machinery of tumor immune escape, and thereby formulating different therapeutic strategies become the imperative missions for clinical and translational researchers to fulfill. After brief basics of CD8+ T cell-based biology is covered, this review delineates the mechanisms of tumor immune escape and discusses different cancer immunotherapy regimens with their own advantages and setbacks, embracing challenges and perspectives in near future.

Treatment Options for Hepatocellular Carcinoma Using Immunotherapy: Present and Future

Hepatocellular carcinoma (HCC) is a common cancer, and the body's immune responses greatly affect its progression and the prognosis of patients. Immunological suppression and the maintenance of self-tolerance in the tumor microenvironment are essential responses, and these form part of the theoretical foundations of immunotherapy. In this review, we first discuss the tumor microenvironment of HCC, describe immunosuppression in HCC, and review the major biomarkers used to track HCC progression and response to treatment. We then examine antibody-based therapies, with a focus on immune checkpoint inhibitors (ICIs), monoclonal antibodies that target key proteins in the immune response (programmed cell death protein 1, anti-cytotoxic T-lymphocyte associated protein 4, and programmed death-ligand 1) which have transformed the treatment of HCC and other cancers. ICIs may be used alone or in conjunction with various targeted therapies for patients with advanced HCC who are receiving first-line treatments or subsequent treatments. We also discuss the use of different cellular immunotherapies, including T cell receptor (TCR) T cell therapy and chimeric antigen receptor (CAR) T cell therapy. We then review the use of HCC vaccines, adjuvant immunotherapy, and oncolytic virotherapy, and describe the goals of future research in the development of treatments for HCC.

Prognosis stratification of cancer patients treated with immune checkpoint inhibitors through lung immune prognostic index: a meta-analysis and systematic review

BACKGROUND

Although numerous studies have reported the prognostic value of the lung immune prognostic index (LIPI) in non-small cell lung cancer (NSCLC) patients treated with immune checkpoint inhibitors (ICIs), the prognostic value of the LIPI in a pancancer setting remains unclear.

METHODS

A comprehensive search was conducted until July 2023 across the PubMed, Embase, Web of Science, and Cochrane Library databases to identify relevant studies evaluating the prognostic value of the LIPI in cancer patients treated with ICIs. The outcomes were overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and disease control rate (DCR). We described and compared the pooled outcomes by stratifying the patients based on different groupings of LIPI (good vs. intermediate [0 vs. 1], good vs. poor [0 vs. 2], and good vs. intermediate / poor [0 vs. 1 + 2]).

RESULTS

A total of 9959 patients in 35 studies were included. A higher score of LIPI was associated with impaired OS. The pooled HRs were 1.69 (95% CI: 1.55-1.85, p < 0.001; 0 vs. 1), 3.03 (95% CI: 2.53-3.63, p < 0.001; 0 vs. 2), and 2.38 (95% CI: 1.97-2.88, p < 0.001; 0 vs. 1 + 2). A higher LIPI score was associated with shorter PFS. The pooled HRs were 1.41 (95% CI: 1.31-1.52, p < 0.001; 0 vs. 1), 2.23 (95% CI: 1.87-2.66, p < 0.001; 0 vs. 2), and 1.65 (95% CI: 1.46-1.86, p < 0.001; 0 vs. 1 + 2). Similarly, a higher LIPI score was associated with a lower ORR. The pooled ORs were 0.63 (95% CI: 0.54-0.75, p < 0.001; 0 vs. 1) and 0.38 (95% CI: 0.29-0.50, p < 0.001; 0 vs. 2). A higher LIPI score was associated with a lower DCR. The pooled ORs were 0.47 (95% CI: 0.35-0.61, p < 0.001; 0 vs. 1) and 0.19 (95% CI: 0.12-0.30, p < 0.001; 0 vs. 2).

CONCLUSION

In patients with NSCLC or other solid tumours, the lung immune prognostic index could robustly stratify the clinical outcomes into three groups among the patients who receive ICIs. LIPI is a low-cost, simple, accessible, and accurate prognostic tool in a pancancer setting and it may contribute to the evaluation of risk stratification in patients treated with ICIs.

Targeting IDH2R140Q and other neoantigens in acute myeloid leukemia

ABSTRACT

For patients with high-risk or relapsed/refractory acute myeloid leukemia (AML), allogeneic stem cell transplantation (allo-HSCT) and the graft-versus-leukemia effect mediated by donor T cells, offer the best chance of long-term remission. However, the concurrent transfer of alloreactive T cells can lead to graft-versus-host disease that is associated with transplant-related morbidity and mortality. Furthermore, ∼60% of patients will ultimately relapse after allo-HSCT, thus, underscoring the need for novel therapeutic strategies that are safe and effective. In this study, we explored the feasibility of immunotherapeutically targeting neoantigens, which arise from recurrent nonsynonymous mutations in AML and thus represent attractive targets because they are exclusively present on the tumor. Focusing on 14 recurrent driver mutations across 8 genes found in AML, we investigated their immunogenicity in 23 individuals with diverse HLA profiles. We demonstrate the immunogenicity of AML neoantigens, with 17 of 23 (74%) reactive donors screened mounting a response. The most immunodominant neoantigens were IDH2R140Q (n = 11 of 17 responders), IDH1R132H (n = 7 of 17), and FLT3D835Y (n = 6 of 17). In-depth studies of IDH2R140Q-specific T cells revealed the presence of reactive CD4+ and CD8+ T cells capable of recognizing distinct mutant-specific epitopes restricted to different HLA alleles. These neo-T cells could selectively recognize and kill HLA-matched AML targets endogenously expressing IDH2R140Q both in vitro and in vivo. Overall, our findings support the clinical translation of neoantigen-specific T cells to treat relapsed/refractory AML.

Checkpoint inhibitor-expressing lentiviral vaccine suppresses tumor growth in preclinical cancer models

BACKGROUND

While immunotherapy has been highly successful for the treatment of some cancers, for others, the immune response to tumor antigens is weak leading to treatment failure. The resistance of tumors to checkpoint inhibitor therapy may be caused by T cell exhaustion resulting from checkpoint activation.

METHODS

In this study, lentiviral vectors that expressed T cell epitopes of an experimentally introduced tumor antigen, ovalbumin, or the endogenous tumor antigen, Trp1 were developed. The vectors coexpressed CD40 ligand (CD40L), which served to mature the dendritic cells (DCs), and a soluble programmed cell death protein 1 (PD-1) microbody to prevent checkpoint activation. Vaccination of mice bearing B16.OVA melanomas with vector-transduced DCs induced the proliferation and activation of functional, antigen-specific, cytolytic CD8 T cells.

RESULTS

Vaccination induced the expansion of CD8 T cells that infiltrated the tumors to suppress tumor growth. Vector-encoded CD40L and PD-1 microbody increased the extent of tumor growth suppression. Adoptive transfer demonstrated that the effect was mediated by CD8 T cells. Direct injection of the vector, without the need for ex vivo transduction of DCs, was also effective.

CONCLUSIONS

This study suggests that therapeutic vaccination that induces tumor antigen-specific CD8 T cells coupled with a vector-expressed checkpoint inhibitor can be an effective means to suppress the growth of tumors that are resistant to conventional immunotherapy.

Clustering of HR + /HER2- breast cancer in an Asian cohort is driven by immune phenotypes

Breast cancer exhibits significant heterogeneity, manifesting in various subtypes that are critical in guiding treatment decisions. This study aimed to investigate the existence of distinct subtypes of breast cancer within the Asian population, by analysing the transcriptomic profiles of 934 breast cancer patients from a Malaysian cohort. Our findings reveal that the HR + /HER2- breast cancer samples display a distinct clustering pattern based on immune phenotypes, rather than conforming to the conventional luminal A-luminal B paradigm previously reported in breast cancers from women of European descent. This suggests that the activation of the immune system may play a more important role in Asian HR + /HER2- breast cancer than has been previously recognized. Analysis of somatic mutations by whole exome sequencing showed that counter-intuitively, the cluster of HR + /HER2- samples exhibiting higher immune scores was associated with lower tumour mutational burden, lower homologous recombination deficiency scores, and fewer copy number aberrations, implicating the involvement of non-canonical tumour immune pathways. Further investigations are warranted to determine the underlying mechanisms of these pathways, with the potential to develop innovative immunotherapeutic approaches tailored to this specific patient population.

Highly variable timing renders immunotherapy efficacy and toxicity impractical biomarkers of one another in clinical practice

Background

A useful clinical biomarker requires not only association but also a consistent temporal relationship. For instance, chemotherapy-induced neutropenia and epidermal growth-factor inhibitor-related acneiform rash both occur within weeks of treatment initiation, thereby providing information prior to efficacy assessment. Although immune checkpoint inhibitor (ICI)-associated immune-related adverse events (irAE) have been associated with therapeutic benefit, irAE may have delayed and highly variable onset. To determine whether ICI efficacy and irAE could serve as clinically useful biomarkers for predicting each other, we determined the temporal relationship between initial efficacy assessment and irAE onset in a diverse population treated with ICI.

Methods

Using two-sided Fisher exact and Cochran-Armitage tests, we determined the relative timing of initial efficacy assessment and irAE occurrence in a cohort of 155 ICI-treated patients (median age 68 years, 40% women).

Results

Initial efficacy assessment was performed a median of 50 days [interquartile range (IQR) 39-59 days] after ICI initiation; median time to any irAE was 77 days (IQR 28-145 days) after ICI initiation. Median time to first irAE was 42 days (IQR 20-88 days). Overall, 58% of any irAE and 47% of first irAE occurred after initial efficacy assessment. For clinically significant (grade ≥2) irAE, 60% of any and 53% of first occurred after initial efficacy assessment. The likelihood of any future irAE did not differ according to response (45% for complete or partial response vs. 47% for other cases; P=1). In landmark analyses controlling for clinical and toxicity follow-up, patients demonstrating greater tumor shrinkage at initial efficacy assessment were more likely to develop future grade ≥2 (P=0.05) and multi-organ (P=0.02) irAE.

Conclusions

In contrast to that seen with chemotherapy and molecularly targeted therapies, the temporal relationship between ICI efficacy and toxicity is complex and bidirectional. In practice, neither parameter can be routinely relied on as a clinical biomarker to predict the other.

Advancing nanotechnology for neoantigen-based cancer theranostics

Neoantigens play a pivotal role in the field of tumour therapy, encompassing the stimulation of anti-tumour immune response and the enhancement of tumour targeting capability. Nonetheless, numerous factors directly influence the effectiveness of neoantigens in bolstering anti-tumour immune responses, including neoantigen quantity and specificity, uptake rates by antigen-presenting cells (APCs), residence duration within the tumour microenvironment (TME), and their ability to facilitate the maturation of APCs for immune response activation. Nanotechnology assumes a significant role in several aspects, including facilitating neoantigen release, promoting neoantigen delivery to antigen-presenting cells, augmenting neoantigen uptake by dendritic cells, shielding neoantigens from protease degradation, and optimizing interactions between neoantigens and the immune system. Consequently, the development of nanotechnology synergistically enhances the efficacy of neoantigens in cancer theranostics. In this review, we provide an overview of neoantigen sources, the mechanisms of neoantigen-induced immune responses, and the evolution of precision neoantigen-based nanomedicine. This encompasses various therapeutic modalities, such as neoantigen-based immunotherapy, phototherapy, radiotherapy, chemotherapy, chemodynamic therapy, and other strategies tailored to augment precision in cancer therapeutics. We also discuss the current challenges and prospects in the application of neoantigen-based precision nanomedicine, aiming to expedite its clinical translation.

Adjuvant and neoadjuvant immunotherapies in hepatocellular carcinoma

Liver cancer, specifically hepatocellular carcinoma (HCC), is the sixth most common cancer and the third leading cause of cancer mortality worldwide. The development of effective systemic therapies, particularly those involving immune-checkpoint inhibitors (ICIs), has substantially improved the outcomes of patients with advanced-stage HCC. Approximately 30% of patients are diagnosed with early stage disease and currently receive potentially curative therapies, such as resection, liver transplantation or local ablation, which result in median overall survival durations beyond 60 months. Nonetheless, up to 70% of these patients will have disease recurrence within 5 years of resection or local ablation. To date, the results of randomized clinical trials testing adjuvant therapy in patients with HCC have been negative. This major unmet need has been addressed with the IMbrave 050 trial, demonstrating a recurrence-free survival benefit in patients with a high risk of relapse after resection or local ablation who received adjuvant atezolizumab plus bevacizumab. In parallel, studies testing neoadjuvant ICIs alone or in combination in patients with early stage disease have also reported efficacy. In this Review, we provide a comprehensive overview of the current approaches to manage patients with early stage HCC. We also describe the tumour immune microenvironment and the mechanisms of action of ICIs and cancer vaccines in this setting. Finally, we summarize the available evidence from phase II/III trials of neoadjuvant and adjuvant approaches and discuss emerging clinical trials, identification of biomarkers and clinical trial design considerations for future studies.

Moving toward improved immune checkpoint immunotherapy for advanced prostate cancer

Human prostate cancer is a heterogenous malignancy that responds poorly to immunotherapy targeting immune checkpoints. The immunosuppressive tumor microenvironment that is typical of human prostate cancer has been the main obstacle to these treatments. The effectiveness of these therapies is also hindered by acquired resistance, leading to slow progress in prostate cancer immunotherapy. Results from the highly anticipated late-stage clinical trials of PD-1/PD-L1 immune checkpoint blockade in patients with advanced prostate cancer have highlighted some of the obstacles to immunotherapy. Despite the setbacks, there is much that has been learned about the mechanisms that drive resistance, and new strategies are being developed and tested. Here, we review the status of immune checkpoint blockade and the immunosuppressive tumor microenvironment and discuss factors contributing to innate and adaptive resistance to immune checkpoint blockade within the context of prostate cancer. We then examine current strategies aiming to overcome these challenges as well as prospects.

Personalized neoantigen vaccine and pembrolizumab in advanced hepatocellular carcinoma: a phase 1/2 trial

Programmed cell death protein 1 (PD-1) inhibitors have modest efficacy as a monotherapy in hepatocellular carcinoma (HCC). A personalized therapeutic cancer vaccine (PTCV) may enhance responses to PD-1 inhibitors through the induction of tumor-specific immunity. We present results from a single-arm, open-label, phase 1/2 study of a DNA plasmid PTCV (GNOS-PV02) encoding up to 40 neoantigens coadministered with plasmid-encoded interleukin-12 plus pembrolizumab in patients with advanced HCC previously treated with a multityrosine kinase inhibitor. Safety and immunogenicity were assessed as primary endpoints, and treatment efficacy and feasibility were evaluated as secondary endpoints. The most common treatment-related adverse events were injection-site reactions, observed in 15 of 36 (41.6%) patients. No dose-limiting toxicities or treatment-related grade ≥3 events were observed. The objective response rate (modified intention-to-treat) per Response Evaluation Criteria in Solid Tumors 1.1 was 30.6% (11 of 36 patients), with 8.3% (3 of 36) of patients achieving a complete response. Clinical responses were associated with the number of neoantigens encoded in the vaccine. Neoantigen-specific T cell responses were confirmed in 19 of 22 (86.4%) evaluable patients by enzyme-linked immunosorbent spot assays. Multiparametric cellular profiling revealed active, proliferative and cytolytic vaccine-specific CD4+ and CD8+ effector T cells. T cell receptor β-chain (TCRβ) bulk sequencing results demonstrated vaccination-enriched T cell clone expansion and tumor infiltration. Single-cell analysis revealed posttreatment T cell clonal expansion of cytotoxic T cell phenotypes. TCR complementarity-determining region cloning of expanded T cell clones in the tumors following vaccination confirmed reactivity against vaccine-encoded neoantigens. Our results support the PTCV's mechanism of action based on the induction of antitumor T cells and show that a PTCV plus pembrolizumab has clinical activity in advanced HCC. ClinicalTrials.gov identifier: NCT04251117 .

Research progress of immunotherapy against anaplastic thyroid cancer

Anaplastic thyroid cancer (ATC) is the most aggressive type of thyroid cancer. While ATC is rare, its mortality is high. Standard treatments, such as surgery, radiotherapy, and chemotherapy, have demonstrated limited efficacy in managing ATC. However, the advent of immunotherapy has significantly improved the prognosis for patients with ATC. Immunotherapy effectively targets and eliminates tumor cells by using the power of the body's immune cells. The neoantigen is an atypical protein generated by somatic mutation, is exclusively observed in neoplastic cells, and is devoid of central tolerance. Neoantigens exhibit enhanced specificity towards tumor cells and display robust immunogenic properties. Currently, neoantigen therapy is primarily applied in immune checkpoint inhibitors and cellular immunotherapy, encompassing adoptive immunotherapy and tumor vaccines. This study discusses the mechanism, tumor microenvironment, clinical trials, adverse events, limitations and future directions associated with ATC immunotherapy.

Unveiling the immunosuppressive landscape of pancreatic ductal adenocarcinoma: implications for innovative immunotherapy strategies

Pancreatic cancer, particularly pancreatic ductal adenocarcinoma (PDAC), stands as the fourth leading cause of cancer-related deaths in the United States, marked by challenging treatment and dismal prognoses. As immunotherapy emerges as a promising avenue for mitigating PDAC's malignant progression, a comprehensive understanding of the tumor's immunosuppressive characteristics becomes imperative. This paper systematically delves into the intricate immunosuppressive network within PDAC, spotlighting the significant crosstalk between immunosuppressive cells and factors in the hypoxic acidic pancreatic tumor microenvironment. By elucidating these mechanisms, we aim to provide insights into potential immunotherapy strategies and treatment targets, laying the groundwork for future studies on PDAC immunosuppression. Recognizing the profound impact of immunosuppression on PDAC invasion and metastasis, this discussion aims to catalyze the development of more effective and targeted immunotherapies for PDAC patients.

DNAJB1-PRKACA fusion neoantigens elicit rare endogenous T cell responses that potentiate cell therapy for fibrolamellar carcinoma

Fibrolamellar carcinoma (FLC) is a liver tumor with a high mortality burden and few treatment options. A promising therapeutic vulnerability in FLC is its driver mutation, a conserved DNAJB1-PRKACA gene fusion that could be an ideal target neoantigen for immunotherapy. In this study, we aim to define endogenous CD8 T cell responses to this fusion in FLC patients and evaluate fusion-specific T cell receptors (TCRs) for use in cellular immunotherapies. We observe that fusion-specific CD8 T cells are rare and that FLC patient TCR repertoires lack large clusters of related TCR sequences characteristic of potent antigen-specific responses, potentially explaining why endogenous immune responses are insufficient to clear FLC tumors. Nevertheless, we define two functional fusion-specific TCRs, one of which has strong anti-tumor activity in vivo. Together, our results provide insights into the fragmented nature of neoantigen-specific repertoires in humans and indicate routes for clinical development of successful immunotherapies for FLC.

Chemical immunology: Recent advances in tool development and applications

Immunology was one of the first biological fields to embrace chemical approaches. The development of new chemical approaches and techniques has provided immunologists with an impressive arsenal of tools to address challenges once considered insurmountable. This review focuses on advances at the interface of chemistry and immunobiology over the past two decades that have not only opened new avenues in basic immunological research, but also revolutionized drug development for the treatment of cancer and autoimmune diseases. These include chemical approaches to understand and manipulate antigen presentation and the T cell priming process, to facilitate immune cell trafficking and regulate immune cell functions, and therapeutic applications of chemical approaches to disease control and treatment.

Recent advances in light-triggered cancer immunotherapy

Light-triggered phototherapies, such as photodynamic therapy (PDT) and photothermal therapy (PTT), have shown strong therapeutic efficacy with minimal invasiveness and systemic toxicity, offering opportunities for tumor-specific therapies. Phototherapies not only induce direct tumor cell killing, but also trigger anti-tumor immune responses by releasing various immune-stimulating factors. In recent years, conventional phototherapies have been combined with cancer immunotherapy as synergistic therapeutic modalities to eradicate cancer by exploiting the innate and adaptive immunity. These combined photoimmunotherapies have demonstrated excellent therapeutic efficacy in preventing tumor recurrence and metastasis compared to phototherapy alone. This review covers recent advancements in combined photoimmunotherapy, including photoimmunotherapy (PIT), PDT-combined immunotherapy, and PTT-combined immunotherapy, along with their underlying anti-tumor immune response mechanisms. In addition, the challenges and future research directions for light-triggered cancer immunotherapy are discussed.

An engineered influenza virus to deliver antigens for lung cancer vaccination

The development of cancer neoantigen vaccines that prime the anti-tumor immune responses has been hindered in part by challenges in delivery of neoantigens to the tumor. Here, using the model antigen ovalbumin (OVA) in a melanoma model, we demonstrate a chimeric antigenic peptide influenza virus (CAP-Flu) system for delivery of antigenic peptides bound to influenza A virus (IAV) to the lung. We conjugated attenuated IAVs with the innate immunostimulatory agent CpG and, after intranasal administration to the mouse lung, observed increased immune cell infiltration to the tumor. OVA was then covalently displayed on IAV-CPG using click chemistry. Vaccination with this construct yielded robust antigen uptake by dendritic cells, a specific immune cell response and a significant increase in tumor-infiltrating lymphocytes compared to peptides alone. Lastly, we engineered the IAV to express anti-PD1-L1 nanobodies that further enhanced regression of lung metastases and prolonged mouse survival after rechallenge. Engineered IAVs can be equipped with any tumor neoantigen of interest to generate lung cancer vaccines.

Case report: A case of advanced gastric cancer with multiple skin metastases, with significant relief from immunotherapy

Gastric cancer is the fifth leading cause of cancer-related mortality worldwide, with a low 5-year survival rate in advanced stages. Cutaneous metastasis is rare in gastric cancer, with only 0.8-1% incidence. We reported a rare case of female gastric cancer. The patient had undergone subtotal gastrectomy and chemotherapy 13 years ago, followed by a subsequent surgery of residual stomach, partial jejunum, and partial colon resection 11 years later. The pathological examination revealed poorly differentiated stomach adenocarcinoma, Lauren classification: diffuse type. The patient received 2 cycles of SOX chemotherapy. Two years later, cauliflower-like skin nodules, which were surgically excised, appeared on the back. The histopathological examination showed a spindle cell tumor; no specific anti-tumor treatment was administered. Six months later, the skin lesions increased in size and number, spreading to the neck, chest, and abdomen, presenting as erythematous patches with some cauliflower-like elevations. A skin biopsy of a 1cm0.5cm0.3cm lesion on the left abdomen was performed, and based on the immunohistochemistry, clinical history, and the possibility of metastatic or infiltrating adenocarcinoma, the gastrointestinal origin was highly suspected. Genetic testing was performed on the gastric recurrence and skin lesions, revealing 103 shared genetic variations, further suggesting the skin metastasis originated from gastric cancer. Subsequently, the patient received 10 cycles of immunotherapy combined with intravenous chemotherapy (200mg Tislelizumab and 100mg albumin-bound paclitaxel). The treatment response was evaluated as partial remission, with significant improvement in the skin lesions compared to before. This case highlights the possibility of tumor metastasis in patients with extensive skin lesions in advanced gastric cancer. Early examination, diagnosis, skin biopsy, immunohistochemistry, and genetic sequencing are recommended.

Stimulating T cell responses against patient-derived breast cancer cells with neoantigen peptide-loaded peripheral blood mononuclear cells

Breast cancer stands as a formidable global health challenge for women. While neoantigens exhibit efficacy in activating T cells specific to cancer and instigating anti-tumor immune responses, the accuracy of neoantigen prediction remains suboptimal. In this study, we identified neoantigens from the patient-derived breast cancer cells, PC-B-142CA and PC-B-148CA cells, utilizing whole-genome and RNA sequencing. The pVAC-Seq pipeline was employed, with minor modification incorporating criteria (1) binding affinity of mutant (MT) peptide with HLA (IC50 MT) ≤ 500 nm in 3 of 5 algorithms and (2) IC50 wild type (WT)/MT > 1. Sequencing results unveiled 2513 and 3490 somatic mutations, and 646 and 652 non-synonymous mutations in PC-B-142CA and PC-B-148CA, respectively. We selected the top 3 neoantigens to perform molecular dynamic simulation and synthesized 9-12 amino acid neoantigen peptides, which were then pulsed onto healthy donor peripheral blood mononuclear cells (PBMCs). Results demonstrated that T cells activated by ADGRL1E274K, PARP1E619K, and SEC14L2R43Q peptides identified from PC-B-142CA exhibited significantly increased production of interferon-gamma (IFN-γ), while PARP1E619K and SEC14L2R43Q peptides induced the expression of CD107a on T cells. The % tumor cell lysis was notably enhanced by T cells activated with MT peptides across all three healthy donors. Moreover, ALKBH6V83M and GAAI823T peptides from PC-B-148CA remarkably stimulated IFN-γ- and CD107a-positive T cells, displaying high cell-killing activity against target cancer cells. In summary, our findings underscore the successful identification of neoantigens with anti-tumor T cell functions and highlight the potential of personalized neoantigens as a promising avenue for breast cancer treatment.

SOCS1 expression in cancer cells: potential roles in promoting antitumor immunity

Suppressor of cytokine signaling 1 (SOCS1) is a potent regulator immune cell responses and a proven tumor suppressor. Inhibition of SOCS1 in T cells can boost antitumor immunity, whereas its loss in tumor cells increases tumor aggressivity. Investigations into the tumor suppression mechanisms so far focused on tumor cell-intrinsic functions of SOCS1. However, it is possible that SOCS1 expression in tumor cells also regulate antitumor immune responses in a cell-extrinsic manner via direct and indirect mechanisms. Here, we discuss the evidence supporting the latter, and its implications for antitumor immunity.