Tertiary lymphoid structures correlate with enhancement of antitumor immunity in esophageal squamous cell carcinoma

The Extra-Tumoral Vaccine Effects of Apoptotic Bodies in the Advancement of Cancer Treatment

The induction of apoptosis in tumor cells is a common target for the development of anti-tumor therapies; however, these therapies still leave patients at increased risk of disease recurrence. For example, apoptotic tumor cells can promote tumor growth and immune evasion via the secretion of metabolites, apoptotic extracellular vesicles, and induction of pro-tumorigenic macrophages. This paradox of apoptosis induction and the pro-tumorigenic effects of tumor cell apoptosis has begged the question of whether apoptosis is a suitable cancer therapy, and led to further explorations into other immunogenic cell death-based approaches. However, these strategies still face multiple challenges, the most critical of which is the tumor microenvironment. Contrary to the promotion of immune tolerance mediated by apoptotic tumor cells, apoptotic bodies with enriched tumor-related antigens have demonstrated great immunogenic potential, as evidenced by their ability to initiate systemic T-cell immune responses. These characteristics indicate that apoptotic body-based therapies could be ideal "in situ" extra-tumoral tumor vaccine candidates for the treatment of cancers, and further address the current issues with apoptosis-based or immunotherapy treatments. Although not yet tested clinically, apoptotic body-based vaccines have the potential to better treatment strategies and patient outcomes in the future.

Tumor infiltration of inactive CD8 + T cells was associated with poor prognosis in Gastric Cancer

BACKGROUND

Gastric cancer (GC) shows limited response to immune checkpoint inhibitors due to its complex tumor immune microenvironment (TIME). This study explores the functions of various immune cells in the complex TIME in GC.

METHODS

We assessed CD8 + T-cell infiltration of GC tissues by immunohistochemistry, and performed single-cell RNA sequencing (scRNA-seq) of tumor and normal tissues from 34 patients with GC.

RESULTS

We categorized 157 GC patients into LOW, MID, and HIGH groups based on their CD8 + T-cell infiltration. Overall survival was notably lower for the HIGH and LOW groups compared with the MID group. Our scRNA-seq data analysis showed that CD8 + T-cell activity markers in the HIGH group were expressed at lower levels than in normal tissue, but the T-cell-attracting chemokine CCL5 was expressed at a higher level. Notably, CD8 + T-cells in the HIGH group displayed lower PD1 expression and higher CTLA4 expression. TCR repertoire analysis using only Epstein-Barr virus-negative cases showed that CD8 + T-cell receptor clonality was lower in the HIGH group than in the MID group. Furthermore, in the HIGH group, the antigen-presenting capacity of type 1 conventional dendritic cells was lower, the immunosuppressive capacity of myeloid-derived suppressor cells was higher, and the expression of CTLA4 in regulatory T-cells was higher.

CONCLUSION

The present data suggest that the infiltration of inactive CD8 + T-cells with low clonality is induced by chemotaxis in the HIGH group, possibly leading to a poor prognosis for patients with GC.

Tertiary Lymphoid Structures are Linked to Enhanced Antitumor Immunity and Better Prognosis in Muscle-Invasive Bladder Cancer

The prognosis for muscle-invasive bladder cancer (MIBC) remains poor, and reliable prognostic markers have yet to be identified. Tertiary lymphoid structures (TLS) have been associated with favorable outcomes in certain cancers. However, the relationship between TLS and MIBC remains unclear. A multi-omics approach is utilized, leveraging single-cell RNA sequencing, spatial transcriptomics, bulk RNA sequencing, and immunohistochemistry, to investigate the roles of B cells and TLS in MIBC. These findings indicate that elevated levels of B cells and TLS correlate with improved prognoses in patients with MIBC, aligning with the robust antitumor immune responses observed in the TLS region. From a mechanistic perspective, CXCL13 serves as a critical cytokine for TLS formation in MIBC, primarily secreted by clonally expanded CXCL13+ T cells. This cytokine interacts with the CXCR5 receptor on NR4A2+ B cells, promoting TLS development. Plasma cells arising within the TLS microenvironment predominantly produce the IGHG antibody, potentially enhancing the phagocytic capabilities of C1QC+ macrophages. From an application standpoint, a TLS-specific gene signature is developed that effectively predicts outcomes in MIBC and other cancers. This study highlights the prognostic potential of TLS in MIBC and reveals immune mechanisms, offering insights for personalized treatment strategies.

An Introduction to Tertiary Lymphoid Structures in Cancer

Immunotherapy has revolutionized therapeutics for cancer patients, which signifies the importance of effective antitumor immunity in combatting cancer. However, the benefit of immunotherapies is limited to specific patient populations and tumor types, suggesting the overt need for new immunotherapeutic targets. Tertiary lymphoid structures (TLS) are ectopic lymph node-like structures that develop at the sites of chronic inflammation such as cancer. TLS are correlated with favorable clinical outcomes across multiple solid tumors and are associated with increased tumor-infiltrating lymphocytes (TILs), particularly effector memory CD8+ T cells. Despite strong clinical data in humans, there are still major knowledge gaps on the function of TLS in cancer. Herein, we highlight the known biology and clinical impact of TLS, which offer further evidence to harness TLS for improved immunotherapeutics.

HLA class II neoantigen presentation for CD4+ T cell surveillance in HLA class II-negative colorectal cancer

Neoantigen-reactive CD4+ T cells play a key role in the anti-tumor immune response. However, the majority of epithelial tumors are negative for HLA class II (HLA-II) surface expression, and less is known about the processing of HLA-II antigens. Here, we directly identified naturally presented HLA-II neoantigens in HLA-II negative colorectal cancer (CRC) tissue using a proteogenomic approach. The neoantigens were immunogenic and induced patient CD4+ T cells with a Th1-like memory phenotype that produced IFN-γ, IL2 and TNF-α. Multiplex immunohistochemistry (IHC) demonstrated an interaction between Th cells and HLA-II-positive antigen-presenting cells (APCs) at the invasive margin and within the tertiary lymphoid structures (TLS). In our CRC cohort, the density of stromal APCs was associated with HLA-II antigen presentation in the tumor microenvironment (TME), and the number of TLS was positively correlated with the number of somatic mutations in the tumors. These results demonstrate the presence of neoantigen-specific CD4+ surveillance in HLA-II-negative CRC and suggest a potential role for macrophages and dendritic cells (DCs) at the invasive margin and in TLS for antigen presentation. Stromal APCs in the TME can potentially be used as a source for HLA-II neoantigen identification.

Gut microbiota in cancer initiation, development and therapy

Cancer has long been associated with genetic and environmental factors, but recent studies reveal the important role of gut microbiota in its initiation and progression. Around 13% of cancers are linked to infectious agents, highlighting the need to identify the specific microorganisms involved. Gut microbiota can either promote or inhibit cancer growth by influencing oncogenic signaling pathways and altering immune responses. Dysbiosis can lead to cancer, while certain probiotics and their metabolites may help reestablish micro-ecological balance and improve anti-tumor immune responses. Research into targeted approaches that enhance therapy with probiotics is promising. However, the effects of probiotics in humans are complex and not yet fully understood. Additionally, methods to counteract harmful bacteria are still in development. Early clinical trials also indicate that modifying gut microbiota may help manage side effects of cancer treatments. Ongoing research is crucial to understand better how gut microbiota can be used to improve cancer prevention and treatment outcomes.

From tumor microenvironment to emerging biomarkers: the reshaping of the esophageal squamous cell carcinoma tumor microenvironment by neoadjuvant chemotherapy combined with immunotherapy

Esophageal squamous cell carcinoma is a cancer with high morbidity and mortality. The advent of immune checkpoint inhibitors has significantly increased complete response rates and postoperative R0 resection rates after neoadjuvant therapy. These drugs can largely reverse the suppression of the immune system caused by the tumor microenvironment, allowing the reactivation of anti-tumor immune infiltrating cells, significantly improving the patient's tumor microenvironment, and thus preventing tumor development. However, there are still some patients who respond poorly to neoadjuvant combined immunotherapy and cannot achieve the expected results. It is now found that exploring changes in the tumor microenvironment not only elucidates patient responsiveness to immunotherapy and identifies more reliable biomarkers, but also addresses the limitations of prediction with imaging examination such as CT and the instability of existing biomarkers. In light of these considerations, this review aims to delve into the alterations within the tumor microenvironment and identify potential predictive biomarkers ensuing from neoadjuvant immunotherapy in the context of esophageal squamous cell carcinoma.

Induction Therapy of Tislelizumab Combined with Cisplatin and 5-Fluorouracil and Subsequent Conversion Surgery in Patients with Unresectable Advanced Esophageal Squamous Cell Carcinoma: A Phase 2, Single Center Study

BACKGROUND

This study reported the safety and efficacy of a phase 2, open-label, single-arm, exploratory clinical trial of induction immunochemotherapy in patients with initially unresectable advanced esophageal squamous cell carcinoma (ESCC).

PATIENTS AND METHODS

Patients underwent three cycles of induction therapy with tislelizumab, cisplatin, and 5-fluorouracil. The primary endpoints were the safety, major pathological response (MPR), and pathological complete response (pCR). Secondary endpoints included the R0 resection rate, disease-free survival (DFS), and overall survival (OS). Genomic data and immune microenvironment data were analyzed exploratively.

RESULTS

The treatment was safe, with a grade 3 or higher adverse event rate of 14.9% (7/47). Of the total 47 patients enrolled in the study, 19 (40.4%) achieved MPR, 12 (25.5%) achieved pCR, 4 (8.5%) achieved complete clinical response (cCR) and declined surgery, and 23 (48.94%) underwent successful resection. Median follow-up was 18 months, with a median DFS of 24 months, a median OS of 36 months. A high tumor mutation burden was associated with a better prognosis for patients who underwent surgery. Patients who achieved pCR had higher levels of immune cell infiltration and a greater proportion and concentration of tertiary lymphoid structures compared with those who experienced a major pathological response.

CONCLUSIONS

Tislelizumab combined with chemotherapy is effective for ESCC, yielding high cCR, pCR, surgical conversion, and R0 resection rates, and tolerable adverse events.

TRIAL REGISTRATION

NCT05469061.

Single-cell sequencing reveals immune features of treatment response to neoadjuvant immunochemotherapy in esophageal squamous cell carcinoma

Neoadjuvant immunochemotherapy (nICT) has dramatically changed the treatment landscape of operable esophageal squamous cell carcinoma (ESCC), but factors influencing tumor response to nICT are not well understood. Here, using single-cell RNA sequencing paired with T cell receptor sequencing, we profile tissues from ESCC patients accepting nICT treatment and characterize the tumor microenvironment context. CXCL13+CD8+ Tex cells, a subset of exhausted CD8+ T cells, are revealed to highly infiltrate in pre-treatment tumors and show prominent progenitor exhaustion phenotype in post-treatment samples from responders. We validate CXCL13+CD8+ Tex cells as a predictor of improved response to nICT and reveal CXCL13 to potentiate anti-PD-1 efficacy in vivo. Post-treatment tumors from non-responders are enriched for CXCL13+CD8+ Tex cells with notably remarkable exhaustion phenotype and TNFRSF4+CD4+ Tregs with activated immunosuppressive function and a significant clone expansion. Several critical markers for therapeutic resistance are also identified, including LRRC15+ fibroblasts and SPP1+ macrophages, which may recruit Tregs to form an immunosuppressive landscape. Overall, our findings unravel immune features of distinct therapeutic response to nICT treatment, providing a rationale for optimizing individualized neoadjuvant strategy in ESCC.

Cold and hot tumors: from molecular mechanisms to targeted therapy

Immunotherapy has made significant strides in cancer treatment, particularly through immune checkpoint blockade (ICB), which has shown notable clinical benefits across various tumor types. Despite the transformative impact of ICB treatment in cancer therapy, only a minority of patients exhibit a positive response to it. In patients with solid tumors, those who respond well to ICB treatment typically demonstrate an active immune profile referred to as the "hot" (immune-inflamed) phenotype. On the other hand, non-responsive patients may exhibit a distinct "cold" (immune-desert) phenotype, differing from the features of "hot" tumors. Additionally, there is a more nuanced "excluded" immune phenotype, positioned between the "cold" and "hot" categories, known as the immune "excluded" type. Effective differentiation between "cold" and "hot" tumors, and understanding tumor intrinsic factors, immune characteristics, TME, and external factors are critical for predicting tumor response and treatment results. It is widely accepted that ICB therapy exerts a more profound effect on "hot" tumors, with limited efficacy against "cold" or "altered" tumors, necessitating combinations with other therapeutic modalities to enhance immune cell infiltration into tumor tissue and convert "cold" or "altered" tumors into "hot" ones. Therefore, aligning with the traits of "cold" and "hot" tumors, this review systematically delineates the respective immune characteristics, influencing factors, and extensively discusses varied treatment approaches and drug targets based on "cold" and "hot" tumors to assess clinical efficacy.

Tertiary Lymphoid Structures in Microorganism-Related Cancer

Tertiary lymphoid structures (TLSs) are ectopic lymphoid tissues formed by the accumulation of lymphocytes and other components outside lymphoid organs. They have been shown to be widespread in cancers and have predictive effects on prognosis and immunotherapy efficacy; however, there is no standardized measurement guide. This paper provides a reference for future research. Moreover, the induction strategy for the formation mechanism of TLSs is a new direction for future cancer treatment, such as cancer vaccines for microorganisms. The effects of microorganisms on cancer are dual. The role of microorganisms, including bacteria, parasites, viruses, and fungi, in promoting cancer has been widely confirmed. However, the specific mechanism of their tumor suppressor effect, particularly the promotion of TLS formation, is currently unknown. In this review, we summarize the role of TLSs in cancer related to microbial infection and provide new ideas for further understanding their mechanisms of action in cancer.

Survival benefit and spatial properties of tertiary lymphoid structures in esophageal squamous cell carcinoma with neoadjuvant therapies

Tertiary lymphoid structures (TLSs) were associated with survival in esophageal squamous cell carcinoma (ESCC) undergoing surgery alone (SA). However, their clinical relevance in neoadjuvant therapies remains less known. Here, we firstly investigated the presence, maturation and spatial distribution of TLSs in 359 ESCC patients receiving neoadjuvant chemotherapy (NCT), neoadjuvant immunotherapy (NCI), neoadjuvant chemoradiotherapy (NCRT) or SA. We found mature TLS (MTLS) was an independent prognostic factor in ESCC. NCI group had the lowest immature TLS cases. NCRT group had the lowest MTLSs. MTLSs mostly located in stromal and normal compartments; these MTLSs were positively correlated with neoadjuvant therapy outcomes. NCI group displayed the highest T cells within 150 μm proximity of TLSs among the four groups. Most T cells were dispersed up to more than 150 μm from TLSs, while B cells remained concentrated within TLSs. Innate lymphoid cells and follicular dendritic cells infiltrated and connected with survival differently in NCRT and NCI groups compared with SA group. The novel PD-L1 combined positive score, NCPS, was positively connected with MTLSs and neoadjuvant therapy efficacy. ScRNA-seq analysis revealed TLS+ tumors had increased plasma cells, B cells, Th17, Tfh and Th1, and elevated exhausted CD8+ T cells that highly expressed checkpoint molecules and granzymes. Conclusively, MTLSs favored treatment outcome in ESCC patients receiving multiple neoadjuvant therapies. The spatial distribution of MTLSs was associated with multiregional immune status modified by the neoadjuvant therapies.

Tertiary lymphoid structures' pattern and prognostic value in primary adenocarcinoma of jejunum and ileum

To date, there have been no reports on tertiary lymphoid structures (TLS) in primary adenocarcinoma of jejunum and ileum. In this study, we employed digital pathology image analysis software to classify and quantify TLS, and evaluated the maturity of TLS using immunohistochemistry. Molecular genetics and immunotherapy biomarker detection were performed using next-generation sequencing technology, such as tumor mutational burden (TMB) and microsatellite instability (MSI). The aim of this study was to investigate the presence, location, maturity, association with immunotherapy biomarkers, and prognostic value of TLS in primary adenocarcinoma of jejunum and ileum. Compared to secondary follicle-like TLS (SFL-TLS), intra-tumoral TLS (IT-TLS) were more likely to manifest as early TLS (E-TLS) (P = 0.007). Compared to IT-TLS, SFL-TLS had a higher propensity to occur at the invasive margin (IM) (P = 0.032) and showed a trend towards being more prevalent at the tumor periphery (P = 0.057). In terms of immunotherapy biomarkers, there was a higher trend of IM-TLS density in PD-L1(22C3) score CPS < 1 group compared to PD-L1(22C3) score CPS ≥ 1 group (P = 0.071). TMB-H was significantly associated with MSI-H (P = 0.040). Univariate survival analysis demonstrated a correlation between high SFL-TLS group and prolonged disease free survival (DFS) (P = 0.047). There was also a trend towards prolonged DFS in the E-TLS-high group compared to the E-TLS-low group (P = 0.069). The peri-tumoral TLS (PT-TLS)-high group showed a trend of prolonged overall survival (OS) compared to the PT-TLS-low group (P = 0.090). In conclusion, the majority of TLS were located at the invasive margin and tumor periphery, predominantly consisting of mature TLS, while IT-TLS were mainly immature. Notably, TMB was closely associated with MSI and PD-L1, indicating potential predictive value for immunotherapy in primary adenocarcinoma of jejunum and ileum.

Macrophages and tertiary lymphoid structures as indicators of prognosis and therapeutic response in cancer patients

Tertiary lymphoid structures (TLS) can reflect cancer prognosis and clinical outcomes in various tumour tissues. Tumour-associated macrophages (TAMs) are indispensable components of the tumour microenvironment and play crucial roles in tumour development and immunotherapy. TAMs are associated with TLS induction via the modulation of the T cell response, which is a major component of the TLS. Despite their important roles in cancer immunology, the subtypes of TAMs that influence TLS and their correlation with prognosis are not completely understood. Here, we provide novel insights into the role of TAMs in regulating TLS formation. Furthermore, we discuss the prognostic value of these TAM subtypes and TLS, as well as the current antitumour therapies for inducing TLS. This study highlights an entirely new field of TLS regulation that may lead to the development of an innovative perspective on immunotherapy for cancer treatment.

Tertiary lymphoid structures in diseases: immune mechanisms and therapeutic advances

Tertiary lymphoid structures (TLSs) are defined as lymphoid aggregates formed in non-hematopoietic organs under pathological conditions. Similar to secondary lymphoid organs (SLOs), the formation of TLSs relies on the interaction between lymphoid tissue inducer (LTi) cells and lymphoid tissue organizer (LTo) cells, involving multiple cytokines. Heterogeneity is a distinguishing feature of TLSs, which may lead to differences in their functions. Growing evidence suggests that TLSs are associated with various diseases, such as cancers, autoimmune diseases, transplant rejection, chronic inflammation, infection, and even ageing. However, the detailed mechanisms behind these clinical associations are not yet fully understood. The mechanisms by which TLS maturation and localization affect immune function are also unclear. Therefore, it is necessary to enhance the understanding of TLS development and function at the cellular and molecular level, which may allow us to utilize them to improve the immune microenvironment. In this review, we delve into the composition, formation mechanism, associations with diseases, and potential therapeutic applications of TLSs. Furthermore, we discuss the therapeutic implications of TLSs, such as their role as markers of therapeutic response and prognosis. Finally, we summarize various methods for detecting and targeting TLSs. Overall, we provide a comprehensive understanding of TLSs and aim to develop more effective therapeutic strategies.

B cells present a double-sided effect in digestive system tumors: a review for tumor microenvironment

Over the past few years, there has been an increasing interest in investigating tumor-infiltrating lymphocytes. B lymphocytes (B cells) are extensively distributed within tertiary lymphoid structure (TLS) as multifaceted subgroups and are intimately linked to the anti-tumor properties of TLS, as well as the survival and prognostication of individuals. While the investigation of T lymphocytes in the TLS has advanced to the level of clinical practice, the study of B cells remains limited. The principal impediment to the utilization of B cells in immunotherapy is their notable dual impact on tumors. Compared with tumors in other parts and systems, the function of B cells in the microenvironment of digestive system tumors to promote tumors proliferation, differentiation and migration cannot be ignored. Therefore, this review collects the studies of B cell subsets in tumor microenvironments, particularly related single cell sequencing research. The multifaceted role and function of B cells are investigated in esophageal, liver, colorectal, gastric and pancreatic cancers. And through the identification of B cell subsets and specific markers, this review attempts to explain the reasons why B cells produce different tumor-promoting effects in those tumors. The insights gleaned from this review may provide potential help and support the development of B cell-based immunotherapies.

Innovative prognostic modeling in ESCC: leveraging scRNA-seq and bulk-RNA for dendritic cell heterogeneity analysis

Background

Globally, esophageal squamous cell carcinoma (ESCC) stands out as a common cancer type, characterized by its notably high rates of occurrence and mortality. Recent advancements in treatment methods, including immunotherapy, have shown promise, yet the prognosis remains poor. In the context of tumor development and treatment outcomes, the tumor microenvironment (TME), especially the function of dendritic cells (DCs), is significantly influential. Our study aims to delve deeper into the heterogeneity of DCs in ESCC using single-cell RNA sequencing (scRNA-seq) and bulk RNA analysis.

Methods

In the scRNA-seq analysis, we utilized the SCP package for result visualization and functional enrichment analysis of cell subpopulations. CellChat was employed to identify potential oncogenic mechanisms in DCs, while Monocle 2 traced the evolutionary trajectory of the three DC subtypes. CopyKAT assessed the benign or malignant nature of cells, and SCENIC conducted transcription factor regulatory network analysis, offering a preliminary exploration of DC heterogeneity. In Bulk-RNA analysis, we constructed a prognostic model for ESCC prognosis and immunotherapy response, based on DC marker genes. This model was validated through quantitative PCR (qPCR) and immunohistochemistry (IHC), confirming the gene expression levels.

Results

In this study, through intercellular communication analysis, we identified GALECTIN and MHC-I signaling pathways as potential oncogenic mechanisms within dendritic cells. We categorized DCs into three subtypes: plasmacytoid (pDC), conventional (cDC), and tolerogenic (tDC). Our findings revealed that pDCs exhibited an increased proportion of cells in the G2/M and S phases, indicating enhanced cellular activity. Pseudotime trajectory analysis demonstrated that cDCs were in early stages of differentiation, whereas tDCs were in more advanced stages, with pDCs distributed across both early and late differentiation phases. Prognostic analysis highlighted a significant correlation between pDCs and tDCs with the prognosis of ESCC (P< 0.05), while no significant correlation was observed between cDCs and ESCC prognosis (P = 0.31). The analysis of cell malignancy showed the lowest proportion of malignant cells in cDCs (17%), followed by pDCs (29%), and the highest in tDCs (48%), with these results being statistically significant (P< 0.05). We developed a robust ESCC prognostic model based on marker genes of pDCs and tDCs in the GSE53624 cohort (n = 119), which was validated in the TCGA-ESCC cohort (n = 139) and the IMvigor210 immunotherapy cohort (n = 298) (P< 0.05). Additionally, we supplemented the study with a novel nomogram that integrates clinical features and risk assessments. Finally, the expression levels of genes involved in the model were validated using qPCR (n = 8) and IHC (n = 16), thereby confirming the accuracy of our analysis.

Conclusion

This study enhances the understanding of dendritic cell heterogeneity in ESCC and its impact on patient prognosis. The insights gained from scRNA-seq and Bulk-RNA analysis contribute to the development of novel biomarkers and therapeutic targets. Our prognostic models based on DC-related gene signatures hold promise for improving ESCC patient stratification and guiding treatment decisions.

Tertiary lymphoid structures in cancer: immune mechanisms and clinical implications

Cancer is a major cause of death globally, and traditional treatments often have limited efficacy and adverse effects. Immunotherapy has shown promise in various malignancies but is less effective in tumors with low immunogenicity or immunosuppressive microenvironment, especially sarcomas. Tertiary lymphoid structures (TLSs) have been associated with a favorable response to immunotherapy and improved survival in cancer patients. However, the immunological mechanisms and clinical significance of TLS in malignant tumors are not fully understood. In this review, we elucidate the composition, neogenesis, and immune characteristics of TLS in tumors, as well as the inflammatory response in cancer development. An in-depth discussion of the unique immune characteristics of TLSs in lung cancer, breast cancer, melanoma, and soft tissue sarcomas will be presented. Additionally, the therapeutic implications of TLS, including its role as a marker of therapeutic response and prognosis, and strategies to promote TLS formation and maturation will be explored. Overall, we aim to provide a comprehensive understanding of the role of TLS in the tumor immune microenvironment and suggest potential interventions for cancer treatment.