CD4⁺ follicular helper T cell infiltration predicts breast cancer survival

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.

Predictive value of lymphocyte subsets and lymphocyte-to-monocyte ratio in assessing the efficacy of neoadjuvant therapy in breast cancer

Lymphocyte subsets are the most intuitive expression of the body's immune ability, and the lymphocyte-to-monocyte ratio (LMR) also clearly reflect the degree of chronic inflammation activity. The purpose of this study is to investigate their predictive value of lymphocyte subsets and LMR to neoadjuvant therapy (NAT) efficacy in breast cancer patients. In this study, lymphocyte subsets and LMR were compared between breast cancer patients (n = 70) and benign breast tumor female populations (n = 48). Breast cancer patients were treated with NAT, and the chemotherapy response of the breast was evaluated using established criteria. The differences in lymphocyte subsets and LMR were also compared between pathological complete response (pCR) and non-pCR patients before and after NAT. Finally, data were analyzed using SPSS. The analytical results demonstrated that breast cancer patients showed significantly lower levels of CD3 + T cells, CD4 + T cells, CD4 + /CD8 + ratio, NK cells, and LMR compared to benign breast tumor women (P < 0.05). Among breast cancer patients, those who achieved pCR had higher levels of CD4 + T cells, NK cells, and LMR before NAT (P < 0.05). NAT increased CD4 + /CD8 + ratio and decreased CD8 + T cells in pCR patients (P < 0.05). Additionally, both pCR and non-pCR patients exhibited an increase in CD3 + T cells and CD4 + T cells after treatment, but the increase was significantly higher in pCR patients (P < 0.05). Conversely, both pCR and non-pCR patients experienced a decrease in LMR after treatment. However, this decrease was significantly lower in pCR patients (P < 0.05). These indicators demonstrated their predictive value for therapeutic efficacy. In conclusion, breast cancer patients experience tumor-related immunosuppression and high chronic inflammation response. But this phenomenon can be reversed to varying degrees by NAT. It has been found that lymphocyte subsets and LMR have good predictive value for pCR. Therefore, these markers can be utilized to identify individuals who are insensitive to NAT early on, enabling the adjustment of treatment plans and achieving precise breast cancer treatment.

Emerging measurements for tumor-infiltrating lymphocytes in breast cancer

Tumor-infiltrating lymphocytes are a general term for lymphocytes or immune cells infiltrating the tumor microenvironment. Numerous studies have demonstrated tumor-infiltrating lymphocytes to be robust prognostic and predictive biomarkers in breast cancer. Recently, immune checkpoint inhibitors, which directly target tumor-infiltrating lymphocytes, have become part of standard of care treatment for triple-negative breast cancer. Surprisingly, tumor-infiltrating lymphocytes quantified by conventional methods do not predict response to immune checkpoint inhibitors, which highlights the heterogeneity of tumor-infiltrating lymphocytes and the complexity of the immune network in the tumor microenvironment. Tumor-infiltrating lymphocytes are composed of diverse immune cell populations, including cytotoxic CD8-positive T lymphocytes, B cells and myeloid cells. Traditionally, tumor-infiltrating lymphocytes in tumor stroma have been evaluated by histology. However, the standardization of this approach is limited, necessitating the use of various novel technologies to elucidate the heterogeneity in the tumor microenvironment. This review outlines the evaluation methods for tumor-infiltrating lymphocytes from conventional pathological approaches that evaluate intratumoral and stromal tumor-infiltrating lymphocytes such as immunohistochemistry, to the more recent advancements in computer tissue imaging using artificial intelligence, flow cytometry sorting and multi-omics analyses using high-throughput assays to estimate tumor-infiltrating lymphocytes from bulk tumor using immune signatures or deconvolution tools. We also discuss higher resolution technologies that enable the analysis of tumor-infiltrating lymphocytes heterogeneity such as single-cell analysis and spatial transcriptomics. As we approach the era of personalized medicine, it is important for clinicians to understand these technologies.

The Absence of Intra-Tumoral Tertiary Lymphoid Structures is Associated with a Worse Prognosis and mTOR Signaling Activation in Hepatocellular Carcinoma with Liver Transplantation: A Multicenter Retrospective Study

Tertiary lymphoid structure (TLS) can predict the prognosis and sensitivity of tumors to immune checkpoint inhibitors (ICIs) therapy, whether it can be noninvasively predicted by radiomics in hepatocellular carcinoma with liver transplantation (HCC-LT) has not been explored. In this study, it is found that intra-tumoral TLS abundance is significantly correlated with recurrence-free survival (RFS) and overall survival (OS). Tumor tissues with TLS are characterized by inflammatory signatures and high infiltration of antitumor immune cells, while those without TLS exhibit uncontrolled cell cycle progression and activated mTOR signaling by bulk and single-cell RNA-seq analyses. The regulators involved in mTOR signaling (RHEB and LAMTOR4) and S-phase (RFC2, PSMC2, and ORC5) are highly expressed in HCC with low TLS. In addition, the largest cohort of HCC patients is studied with available radiomics data, and a classifier is built to detect the presence of TLS in a non-invasive manner. The classifier demonstrates remarkable performance in predicting intra-tumoral TLS abundance in both training and test sets, achieving areas under receiver operating characteristic curve (AUCs) of 92.9% and 90.2% respectively. In summary, the absence of intra-tumoral TLS abundance is associated with mTOR signaling activation and uncontrolled cell cycle progression in tumor cells, indicating unfavorable prognosis in HCC-LT.

Exploiting tertiary lymphoid structures gene signature to evaluate tumor microenvironment infiltration and immunotherapy response in colorectal cancer

Background

Tertiary lymphoid structures (TLS) is a particular component of tumor microenvironment (TME). However, its biological mechanisms in colorectal cancer (CRC) have not yet been understood. We desired to reveal the TLS gene signature in CRC and evaluate its role in prognosis and immunotherapy response.

Methods

The data was sourced from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. Based on TLS-related genes (TRGs), the TLS related subclusters were identified through unsupervised clustering. The TME between subclusters were evaluated by CIBERSORT and xCell. Subsequently, developing a risk model and conducting external validation. Integrating risk score and clinical characteristics to create a comprehensive nomogram. Further analyses were conducted to screen TLS-related hub genes and explore the relationship between hub genes, TME, and biological processes, using random forest analysis, enrichment and variation analysis, and competing endogenous RNA (ceRNA) network analysis. Multiple immunofluorescence (mIF) and immunohistochemistry (IHC) were employed to characterize the existence of TLS and the expression of hub gene.

Results

Two subclusters that enriched or depleted in TLS were identified. The two subclusters had distinct prognoses, clinical characteristics, and tumor immune infiltration. We established a TLS-related prognostic risk model including 14 genes and validated its predictive power in two external datasets. The model's AUC values for 1-, 3-, and 5-year overall survival (OS) were 0.704, 0.737, and 0.746. The low-risk group had a superior survival rate, more abundant infiltration of immune cells, lower tumor immune dysfunction and exclusion (TIDE) score, and exhibited better immunotherapy efficacy. In addition, we selected the top important features within the model: VSIG4, SELL and PRRX1. Enrichment analysis showed that the hub genes significantly affected signaling pathways related to TLS and tumor progression. The ceRNA network: PRRX1-miRNA (hsa-miR-20a-5p, hsa-miR-485-5p) -lncRNA has been discovered. Finally, IHC and mIF results confirmed that the expression level of PRRX1 was markedly elevated in the TLS- CRC group.

Conclusion

We conducted a study to thoroughly describe TLS gene signature in CRC. The TLS-related risk model was applicable for prognostic prediction and assessment of immunotherapy efficacy. The TLS-hub gene PRRX1, which had the potential to function as an immunomodulatory factor of TLS, could be a therapeutic target for CRC.

A comprehensive single-cell breast tumor atlas defines epithelial and immune heterogeneity and interactions predicting anti-PD-1 therapy response

We present an integrated single-cell RNA sequencing atlas of the primary breast tumor microenvironment (TME) containing 236,363 cells from 119 biopsy samples across eight datasets. In this study, we leverage this resource for multiple analyses of immune and cancer epithelial cell heterogeneity. We define natural killer (NK) cell heterogeneity through six subsets in the breast TME. Because NK cell heterogeneity correlates with epithelial cell heterogeneity, we characterize epithelial cells at the level of single-gene expression, molecular subtype, and 10 categories reflecting intratumoral transcriptional heterogeneity. We develop InteractPrint, which considers how cancer epithelial cell heterogeneity influences cancer-immune interactions. We use T cell InteractPrint to predict response to immune checkpoint inhibition (ICI) in two breast cancer clinical trials testing neoadjuvant anti-PD-1 therapy. T cell InteractPrint was predictive of response in both trials versus PD-L1 (AUC = 0.82, 0.83 vs. 0.50, 0.72). This resource enables additional high-resolution investigations of the breast TME.

HLA-A+ tertiary lymphoid structures with reactivated tumor infiltrating lymphocytes are associated with a positive immunotherapy response in esophageal squamous cell carcinoma

BACKGROUND

Immune checkpoint blockade (ICB) therapy provides remarkable clinical benefits for multiple cancer types. However, the overall response rate to ICB therapy remains low in esophageal squamous cell carcinoma (ESCC). This study aimed to identify biomarkers of ICB therapy for ESCC and interrogate its potential clinical relevance.

METHODS

We investigated gene expression in 42 treatment-naïve ESCC tumor tissues and identified differentially expressed genes, tumor-infiltrating lymphocytes and immune-related genes signatures associated with differential immunotherapy responses. We systematically assessed the tumor microenvironment using the NanoString GeoMx digital spatial profiler, single-cell RNA-seq and multiplex immunohistochemistry in ESCC. Finally, we evaluated the associations between HLA-A-positive tertiary lymphoid structures (TLSs) and patients' responses to ICB in 60 ESCC patients.

RESULTS

Tumor infiltrating B lymphocytes and several immune-related gene signatures, such as the antigen presenting machinery (APM) signature, are significantly elevated in ICB treatment responders. Multiplex immunohistochemistry identified the presence of HLA-A+ TLSs and showed that TLS-resident cells increasingly express HLA-A as TLSs mature. Most TLS-resident HLA-A+ cells are tumor-infiltrating T (TIL-T) or tumor-infiltrating B (TIL-B) lymphocytes. Digital spatial profiling of spatially distinct TIL-T lymphocytes and single-cell RNA-seq data from 60 ESCC tumor tissues revealed that CXCL13-expressing exhausted TIL-Ts inside TLSs are reactivated with elevated expression of the APM signature as TLSs mature. Finally, we demonstrated that HLA-A+ TLSs and their major cellular components, TIL-Ts and TIL-Bs, are associated with a clinical benefit from ICB treatment for ESCC.

CONCLUSIONS

HLA-A+ TLSs are present in ESCC tumor tissues. TLS-resident TIL-Ts with elevated expression of the APM signature may be reactivated. HLA-A+ TLSs and their major cellular components, TIL-Ts and TIL-Bs, may serve as biomarkers for ICB-treated ESCC patients.

Benign breast tumors may arise on different immunological backgrounds

Benign breast tumors are a nonthreatening condition defined as abnormal cell growth within the breast without the ability to invade nearby tissue. However, benign lesions hold valuable biological information that can lead us toward better understanding of tumor biology. In this study, we have used two pathway analysis algorithms, Pathifier and gene set variation analysis (GSVA), to identify biological differences between normal breast tissue, benign tumors and malignant tumors in our clinical dataset. Our results revealed that one-third of all pathways that were significantly different between benign and malignant tumors were immune-related pathways, and 227 of them were validated by both methods and in the METABRIC dataset. Furthermore, five of these pathways (all including genes involved in cytokine and interferon signaling) were related to overall survival in cancer patients in both datasets. The cellular moieties that contribute to immune differences in malignant and benign tumors were analyzed using the deconvolution tool, CIBERSORT. The results showed that levels of some immune cells were specifically higher in benign than in malignant tumors, and this was especially the case for resting dendritic cells and follicular T-helper cells. Understanding the distinct immune profiles of benign and malignant breast tumors may aid in developing noninvasive diagnostic methods to differentiate between them in the future.

High tumour-infiltrating lymphocytes correlate with distinct gene expression profile and favourable survival in single hormone receptor-positive breast cancer

Introduction

This study aimed to evaluate the impact of tumour-infiltrating lymphocytes (TILs) on the expression of immune-related genes and prognosis in single hormone receptor-positive breast cancer. Material and methods: Tumour-infiltrating lymphocytes were analysed according to the guidelines of the International TILs Working Group in a cohort of 206 patients with single hormone receptor-positive breast cancer. Of these, 44.7% were classified as ER+/PgR-/HER2-, 18.4% as ER+/PgR-/HER2+, 26.2% as ER-/PgR+/HER2-, and 10.7% as ER-/PgR+/HER2+. Moreover, in 52 samples the analysis of gene expression profiling was performed using nCounter technology.

Results

Most cases (74.3%) showed at least 1% of stromal TILs, with a median of 4%, mean of 16.3%, and interquartile range of 0-20%. ER-/PgR+ tumours displayed significantly higher TILs density than ER+/PgR- cases (p < 0.001, Wilcoxon test), regardless of HER2 status. The abundance of TILs was positively associated with ER-/PgR+ phenotype, higher Ki-67, and higher grade, but not with age, tumour size, or regional and distant metastases at diagnosis. Additionally, in ER+/PgR- subgroup higher TILs were associated with HER2-positive status. Stromal TILs > 5% were associated with better survival in the whole group, but this effect was less prominent in ER-/PgR+ patients. We identified 50 differentially expressed genes (DEGs) between single hormone receptor-positive breast tumours with high and low TILs, including 39 up-regulated and 11 down-regulated genes in the high TILs group.

Conclusions

The up-regulated expression of immune-related genes was consistent also among separately analysed single hormone receptor-positive groups (ER+/PgR- and ER-/PgR+).

In-depth immune profiling of peripheral blood mononuclear cells in patients with pancreatic ductal adenocarcinoma reveals discriminative immune subpopulations

Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis with a 5-year survival of less than 10%. More knowledge of the immune response developed in patients with PDAC is pivotal to develop better combination immune therapies to improve clinical outcome. In this study, we used mass cytometry time-of-flight to undertake an in-depth characterization of PBMCs from patients with PDAC and examine the differences with healthy controls and patients with benign diseases of the biliary system or pancreas. Peripheral blood mononuclear cells from patients with PDAC or benign disease are characterized by the increase of pro-inflammatory cells, as CD86+ classical monocytes and memory T cells expressing CCR6+ and CXCR3+, associated with T helper 1 (Th1) and Th17 immune responses, respectively. However, PBMCs from patients with PDAC present also an increase of CD39+ regulatory T cells and CCR4+CCR6-CXCR3- memory T cells, suggesting Th2 and regulatory responses. Concluding, our results show PDAC develops a multifaceted immunity, where a proinflammatory component is accompanied by regulatory responses, which could inhibit potential antitumor mechanisms.

Stromal B Lymphocytes Affecting Prognosis in Triple-Negative Breast Cancer by Opal/TSA Multiplexed Immunofluorescence

Objective

Immune cells play a key role in tumor microenvironment. The purpose of this study was to investigate the infiltration and clinical indication of immune cells including their combined prognostic value in microenvironment of triple negative breast cancer.

Methods

We investigated 100 patients with triple negative breast cancer by Opal/Tyramide Signal Amplification multispectral immunofluorescence between 2003 and 2017 at Zhejiang Provincial people's Hospital. Intratumoral and stromal immune cells of triple negative breast cancer were classified and quantitatively analyzed. Survival outcomes were compared using the Kaplan-Meier method and further analyzed with multivariate analysis.

Results

Infiltration level of stromal B lymphocytes, stromal and intratumoral CD8+ T cells, stromal CD4+ T cells, stromal PD-L1 and intratumoral tumor associated macrophages 2 cells were shown as independent factors affecting disease-free survival and overall survival in univariate analysis. Stromal B lymphocytes, T stage, N stage and pathological type were independent predictive factors for both DFS and OS in multivariate analysis. We firstly found that patients with B lymphocytes-enriched subtypes have a better prognosis than those with T lymphocytes-enriched subtypes and tumor-associated macrophage-enriched subtypes.

Conclusion

The present study identified a bunch of immune targets and subtypes, which could be exploited in future combined immunotherapy/chemotherapy strategies for triple negative breast cancer patients.

Impact of tertiary lymphoid structures on prognosis and therapeutic response in pancreatic ductal adenocarcinoma

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is known to have a heterogeneous desmoplastic tumour microenvironment (TME) with a large number of immunosuppressive cells. Recently, high B-cell infiltration in PDAC has received growing interest as a potential therapeutic target.

METHODS

Our literature review summarises the characteristics of tumour-associated tertiary lymphoid structures (TLSs) and highlight the key studies exploring the clinical outcomes of TLSs in PDAC patients and the direct effect on the TME.

RESULTS

The location, density and maturity stages of TLSs within tumours play a key role in determining the prognosis and is a new emerging target in cancer immunotherapy.

DISCUSSION

TLS development is imperative to improve the prognosis of PDAC patients. In the future, studying the genetics and immune characteristics of tumour infiltrating B cells and TLSs may lead towards enhancing adaptive immunity in PDAC and designing personalised therapies.

Tumor-infiltrating lymphocytes in HER2-positive breast cancer treated with neoadjuvant chemotherapy and dual HER2-blockade

Tumor-infiltrating lymphocytes (TILs) have been associated with outcomes in HER2-positive breast cancer patients treated with neoadjuvant chemotherapy and trastuzumab. However, it remains unclear if TILs could be a prognostic and/or predictive biomarker in the context of dual HER2-targeting treatment. In this study, we evaluated the association between TILs and pathological response (pCR) and invasive-disease free survival (IDFS) in 389 patients with stage II-III HER2 positive breast cancer who received neoadjuvant anthracycline-containing or anthracycline-free chemotherapy combined with trastuzumab and pertuzumab in the TRAIN-2 trial. Although no significant association was seen between TILs and pCR, patients with TIL scores ≥60% demonstrated an excellent 3-year IDFS of 100% (95% CI 100-100), regardless of hormone receptor status, nodal stage and attainment of pCR. Additionally, in patients with hormone receptor positive disease, TILs as a continuous variable showed a trend to a positive association with pCR (adjusted Odds Ratio per 10% increase in TILs 1.15, 95% CI 0.99-1.34, p = 0.070) and IDFS (adjusted Hazard Ratio per 10% increase in TILs 0.71, 95% CI 0.50-1.01, p = 0.058). We found no interactions between TILs and anthracycline treatment. Our results suggest that high TIL scores might be able to identify stage II-III HER2-positive breast cancer patients with a favorable prognosis.

Tertiary lymphoid structures in cancer: maturation and induction

Tertiary lymphoid structure (TLS) is an ectopic lymphocyte aggregate formed in peripheral non-lymphoid tissues, including inflamed or cancerous tissue. Tumor-associated TLS serves as a prominent center of antigen presentation and adaptive immune activation within the periphery, which has exhibited positive prognostic value in various cancers. In recent years, the concept of maturity regarding TLS has been proposed and mature TLS, characterized by well-developed germinal centers, exhibits a more potent tumor-suppressive capacity with stronger significance. Meanwhile, more and more evidence showed that TLS can be induced by therapeutic interventions during cancer treatments. Thus, the evaluation of TLS maturity and the therapeutic interventions that induce its formation are critical issues in current TLS research. In this review, we aim to provide a comprehensive summary of the existing classifications for TLS maturity and therapeutic strategies capable of inducing its formation in tumors.

B cells and the coordination of immune checkpoint inhibitor response in patients with solid tumors

Immunotherapy profoundly changed the landscape of cancer therapy by providing long-lasting responses in subsets of patients and is now the standard of care in several solid tumor types. However, immunotherapy activity beyond conventional immune checkpoint inhibition is plateauing, and biomarkers are overall lacking to guide treatment selection. Most studies have focused on T cell engagement and response, but there is a growing evidence that B cells may be key players in the establishment of an organized immune response, notably through tertiary lymphoid structures. Mechanisms of B cell response include antibody-dependent cellular cytotoxicity and phagocytosis, promotion of CD4+ and CD8+ T cell activation, maintenance of antitumor immune memory. In several solid tumor types, higher levels of B cells, specific B cell subpopulations, or the presence of tertiary lymphoid structures have been associated with improved outcomes on immune checkpoint inhibitors. The fate of B cell subpopulations may be widely influenced by the cytokine milieu, with versatile roles for B-specific cytokines B cell activating factor and B cell attracting chemokine-1/CXCL13, and a master regulatory role for IL-10. Roles of B cell-specific immune checkpoints such as TIM-1 are emerging and could represent potential therapeutic targets. Overall, the expanding field of B cells in solid tumors of holds promise for the improvement of current immunotherapy strategies and patient selection.

Triple-negative breast cancer survival prediction using artificial intelligence through integrated analysis of tertiary lymphoid structures and tumor budding

BACKGROUND

Triple-negative breast cancer (TNBC) is a highly heterogeneous and clinically aggressive disease. Accumulating evidence indicates that tertiary lymphoid structures (TLSs) and tumor budding (TB) are significantly correlated with the outcomes of patients who have TNBC, but no integrated TLS-TB profile has been established to predict their survival. The objective of this study was to investigate the relationship between the TLS/TB ratio and clinical outcomes of patients with TNBC using artificial intelligence (AI)-based analysis.

METHODS

The infiltration levels of TLSs and TB were evaluated using hematoxylin and eosin staining, immunohistochemistry staining, and AI-based analysis. Various cellular subtypes within TLS were determined by multiplex immunofluorescence. Subsequently, the authors established a nomogram model, conducted calibration curve analyses, and performed decision curve analyses using R software.

RESULTS

In both the training and validation cohorts, the antitumor/protumor model established by the authors demonstrated a positive correlation between the TLS/TB index and the overall survival (OS) and relapse-free survival (RFS) of patients with TNBC. Notably, patients who had a high percentage of CD8-positive T cells, CD45RO-positive T cells, or CD20-positive B cells within the TLSs experienced improved OS and RFS. Furthermore, the authors developed a comprehensive TLS-TB profile nomogram based on the TLS/TB index. This novel model outperformed the classical tumor-lymph node-metastasis staging system in predicting the OS and RFS of patients with TNBC.

CONCLUSIONS

A novel strategy for predicting the prognosis of patients with TNBC was established through integrated AI-based analysis and a machine-learning workflow. The TLS/TB index was identified as an independent prognostic factor for TNBC. This nomogram-based TLS-TB profile would help improve the accuracy of predicting the prognosis of patients who have TNBC.

Tertiary lymphoid structural heterogeneity determines tumour immunity and prospects for clinical application

Tertiary lymphoid structures (TLS) are clusters of immune cells that resemble and function similarly to secondary lymphoid organs (SLOs). While TLS is generally associated with an anti-tumour immune response in most cancer types, it has also been observed to act as a pro-tumour immune response. The heterogeneity of TLS function is largely determined by the composition of tumour-infiltrating lymphocytes (TILs) and the balance of cell subsets within the tumour-associated TLS (TA-TLS). TA-TLS of varying maturity, density, and location may have opposing effects on tumour immunity. Higher maturity and/or higher density TLS are often associated with favorable clinical outcomes and immunotherapeutic response, mainly due to crosstalk between different proportions of immune cell subpopulations in TA-TLS. Therefore, TLS can be used as a marker to predict the efficacy of immunotherapy in immune checkpoint blockade (ICB). Developing efficient imaging and induction methods to study TA-TLS is crucial for enhancing anti-tumour immunity. The integration of imaging techniques with biological materials, including nanoprobes and hydrogels, alongside artificial intelligence (AI), enables non-invasive in vivo visualization of TLS. In this review, we explore the dynamic interactions among T and B cell subpopulations of varying phenotypes that contribute to the structural and functional diversity of TLS, examining both existing and emerging techniques for TLS imaging and induction, focusing on cancer immunotherapies and biomaterials. We also highlight novel therapeutic approaches of TLS that are being explored with the aim of increasing ICB treatment efficacy and predicting prognosis.

Anti-PD-1 therapy triggers Tfh cell-dependent IL-4 release to boost CD8 T cell responses in tumor-draining lymph nodes

Anti-PD-1 therapy targets intratumoral CD8+ T cells to promote clinical responses in cancer patients. Recent evidence suggests an additional activity in the periphery, but the underlying mechanism is unclear. Here, we show that anti-PD-1 mAb enhances CD8+ T cell responses in tumor-draining lymph nodes by stimulating cytokine production in follicular helper T cells (Tfh). In two different models, anti-PD-1 mAb increased the activation and proliferation of tumor-specific T cells in lymph nodes. Surprisingly, anti-PD-1 mAb did not primarily target CD8+ T cells but instead stimulated IL-4 production by Tfh cells, the major population bound by anti-PD-1 mAb. Blocking IL-4 or inhibiting the Tfh master transcription factor BCL6 abrogated anti-PD-1 mAb activity in lymph nodes while injection of IL-4 complexes was sufficient to recapitulate anti-PD-1 mAb activity. A similar mechanism was observed in a vaccine model. Finally, nivolumab also boosted human Tfh cells in humanized mice. We propose that Tfh cells and IL-4 play a key role in the peripheral activity of anti-PD-1 mAb.

Machine Learning-Based Characterization and Identification of Tertiary Lymphoid Structures Using Spatial Transcriptomics Data

Tertiary lymphoid structures (TLSs) are organized aggregates of immune cells in non-lymphoid tissues and are associated with a favorable prognosis in tumors. However, TLS markers remain inconsistent, and the utilization of machine learning techniques for this purpose is limited. To tackle this challenge, we began by identifying TLS markers through bioinformatics analysis and machine learning techniques. Subsequently, we leveraged spatial transcriptomic data from Gene Expression Omnibus (GEO) and built two support vector classifier models for TLS prediction: one without feature selection and the other using the marker genes. The comparable performances of these two models confirm the efficacy of the selected markers. The majority of the markers are immunoglobulin genes, demonstrating their importance in the identification of TLSs. Our research has identified the markers of TLSs using machine learning methods and constructed a model to predict TLS location, contributing to the detection of TLS and holding the promising potential to impact cancer treatment strategies.

Tumor-Infiltrating Lymphocytes (TILs) in Breast Cancer: Prognostic and Predictive Significance across Molecular Subtypes

Tumor-infiltrating lymphocytes (TILs) are pivotal in the immune response against breast cancer (BC), with their prognostic and predictive significance varying across BC subtypes. In triple-negative BC (TNBC), higher TIL levels correlate with improved prognosis and treatment response, guiding therapeutic strategies and potentially offering avenues for treatment de-escalation. In metastatic TNBC, TILs identify patients with enhanced immunotherapy response. HER2+ BC, similar to TNBC, exhibits positive correlations between TILs and treatment response, especially in neoadjuvant settings. Luminal BC generally has low TILs, with limited prognostic impact. Single hormone receptor-positive BCs show distinct TIL associations, emphasizing subtype-specific considerations. TILs in ductal carcinoma in situ (DCIS) display ambiguous prognostic significance, necessitating further investigation. Standardizing TIL assessment methods is crucial for unlocking their full potential as biomarkers, guiding treatment decisions, and enhancing patient care in BC.

The anti-cancer immune response in breast cancer: current and emerging biomarkers and treatments

Triple-negative breast cancers (TNBCs) exhibit heightened T cell infiltration, contributing to an enhanced response to immune checkpoint blockade (ICB) compared with other subtypes. An immune-rich immune microenvironment correlates with improved prognosis in early and advanced TNBC. Combination chemotherapy and ICB is now the standard of care in early- and late-stage TNBC. Although programmed death ligand-1 (PD-L1) positivity predicts ICB response in advanced stages, its role in early-stage disease remains uncertain. Despite neoadjuvant ICB becoming common in early-stage TNBC, the necessity of adjuvant ICB after surgery remains unclear. Understanding the molecular basis of the immune response in breast cancer is vital for precise biomarkers for ICB and effective combination therapy strategies.

Clinical significance of low expression of CADM3 in breast cancer and preliminary exploration of related mechanisms

BACKGROUND

Cell adhesion molecule 3 (CADM3), a transmembrane glycoprotein on cell membranes, plays a role in the way of ligand and receptor interaction. However, there are few studies on CADM3 in tumors, and how it works in breast cancer (BC) remains unclear.

METHODS

The Cancer Genome Atlas (TCGA) database and clinical samples were used to analyze CADM3 expression and its correlation with clinicopathological factors and prognosis. Its correlation with immune infiltration was analyzed by TCGA. The effects of CADM3 on proliferation and migration were investigated by cell clonal formation, CCK-8, cell scratch and transwell assay. Protein interaction network was prepared and the function prediction of related genes was conducted. The correlation between CADM3 and MAPK pathway was further explored by western blot experiment.

RESULTS

The expression of CADM3 in BC tissues were significantly lower than that in adjacent normal tissues. High level of CADM3 was related to better prognosis of BC patients. CADM3 was an independent prognostic factor for BC. Expression of CADM3 was significantly associated with the status of ER and PR, age and PAM50 subtypes. CADM3 positively related to many immune infiltrating cells. Overexpression of CADM3 can notably reduce cell proliferation and migration. CADM3 was related to MAPK pathway and the phosphorylation of ERK1/2 and JNK1 was inhibited in BC cells with high CADM3.

CONCLUSIONS

Our research reveals the clinical significance of CADM3 in BC and indicates the critical roles of CADM3 in immune infiltration and MAPK pathway.

Tertiary lymphoid structures predict survival and response to neoadjuvant therapy in locally advanced rectal cancer

Tertiary lymphoid structure (TLS) contributes to the anti-tumor immune response, and predicts the prognosis of colorectal cancer patients. However, the potential impact of TLS in shaping the immune status of rectal adenocarcinoma, and the intrinsic relationship between TLS and neoadjuvant therapies (neoTx) remain unclear. We performed hematoxylin-eosin staining, immunohistochemical and biomolecular analyses to investigate TLS and tumor-infiltrating lymphocytes (TILs) in 221 neoTx-treated and 242 treatment-naïve locally advanced rectal cancer (LARC) patients. High TLS density was significantly associated with the absence of vascular invasion, a lower neutrophil-to-lymphocyte ratio, increased TLS maturity, a longer recurrence-free survival (RFS) (hazard ratio [HR] 0.2985 95% confidence interval [CI] 0.1894-0.4706, p < 0.0001) and enhanced infiltration of adaptive immune cells. Biomolecular analysis showed that high TLS-score was strongly associated with more infiltration of immune cells and increased activation of immune-related pathways. TLS+ tumors in pre-treatment specimens were associated with a higher proportion of good respond (62.5% vs. 29.8%, p < 0.0002) and pathological complete remission (pCR) (40.0% vs. 11.1%, p < 0.0001), and significantly increased RFS (HR 0.3574 95%CI 0.1489-0.8578 p = 0.0213) compared with TLS- tumors in the neoTx cohort, which was confirmed in GSE119409 and GSE150082. Further studies showed that neoTx significantly reduced TLS density and maturity, and abolished the prognostic value of TLS. Our study illustrates that TLS may have a key role in mediating the T-cell-inflamed tumor microenvironment, which also provides a new direction for neoTx, especially neoadjuvant immunotherapy, in LRAC patients.

Can we yet use tertiary lymphoid structures as predictive biomarkers for immunotherapy response in melanoma?

PURPOSE OF REVIEW

In this review, we explore the potential of tertiary lymphoid structures (TLS) as predictive biomarkers in the response to immunotherapy for melanoma patients.

RECENT FINDINGS

The significance of TLS as indicators predicting immunotherapy response becomes particularly pronounced. Melanoma, renowned for its aggressive characteristics, has undergone revolutionary transformations in treatment through immunotherapeutic interventions. Investigations have unveiled a compelling correlation between the presence of TLS in the melanoma tumor microenvironment and favorable responses to immunotherapy. These responses, characterized by heightened survival rates and improved clinical outcomes, imply that TLS might be pivotal in tailoring more efficient and personalized treatments for individuals with melanoma. The ongoing discourse regarding TLS as a predictive biomarker underscores the need for a meticulous examination of its potential in guiding clinical decisions and optimizing therapeutic strategies.

SUMMARY

TLS show great promises as potential biomarkers to melanoma patient's outcomes in ICI treatment; however, more studies are needed to understand their mechanisms of actions and the long-term impact of their functionality.

Mapping spatial heterogeneity in gastric cancer microenvironment

Gastric cancer (GC) is difficult to characterize due to its heterogeneity, and the complicated heterogeneity leads to the difficulty of precisely targeted therapy. The spatially heterogeneous composition plays a crucial role in GC onset, progression, treatment efficacy, and drug resistance. In recent years, the technological advancements in spatial omics has shifted our understanding of the tumor microenvironment (TME) from cancer-centered model to a dynamic and variant whole. In this review, we concentrated on the spatial heterogeneity within the primary lesions and between the primary and metastatic lesions of GC through the TME heterogeneity including the tertiary lymphoid structures (TLSs), the uniquely spatial organization. Meanwhile, the immune phenotype based on spatial distribution was also outlined. Furthermore, we recapitulated the clinical treatment in mediating spatial heterogeneity in GC, hoping to provide a systematic view of how spatial information could be integrated into anti-cancer immunity.

B-Cell-Mediated Immunity Predicts Survival of Patients With Estrogen Receptor-Positive Breast Cancer

PURPOSE

The estrogen receptor-positive (ER+) breast cancer (BC), which constitutes the majority of BC cases, exhibits highly heterogeneous clinical behavior. To aid precision treatments, we aimed to find molecular subtypes of ER+ BC representing the tumor microenvironment and prognosis.

METHODS

We analyzed RNA-seq data of 113 patients with BC and classified them according to the PAM50 intrinsic subtypes using gene expression profiles. Among them, we further focused on 44 patients with luminal-type (ER+) BC for subclassification. The Cancer Genome Atlas (TCGA) data of patients with BC were used as a validation data set to verify the new classification. We estimated the immune cell composition using CIBERSORT and further analyzed its association with clinical or molecular parameters.

RESULTS

Principal component analysis clearly divided the patients into two subgroups separately from the luminal A and B classification. The top differentially expressed genes between the subgroups were distinctly characterized by immunoglobulin and B-cell-related genes. We could also cluster a separate cohort of patients with luminal-type BC from TCGA into two subgroups on the basis of the expression of a B-cell-specific gene set, and patients who were predicted to have high B-cell immune activity had better prognoses than other patients.

CONCLUSION

Our transcriptomic approach emphasize a molecular phenotype of B-cell immunity in ER+ BC that may help to predict disease prognosis. Although further researches are required, B-cell immunity for patients with ER+ BC may be helpful for identifying patients who are good responders to chemotherapy or immunotherapy.

The cellular composition of the tumor microenvironment is an important marker for predicting therapeutic efficacy in breast cancer

At present, the incidence rate of breast cancer ranks first among new-onset malignant tumors in women. The tumor microenvironment is a hot topic in tumor research. There are abundant cells in the tumor microenvironment that play a protumor or antitumor role in breast cancer. During the treatment of breast cancer, different cells have different influences on the therapeutic response. And after treatment, the cellular composition in the tumor microenvironment will change too. In this review, we summarize the interactions between different cell compositions (such as immune cells, fibroblasts, endothelial cells, and adipocytes) in the tumor microenvironment and the treatment mechanism of breast cancer. We believe that detecting the cellular composition of the tumor microenvironment is able to predict the therapeutic efficacy of treatments for breast cancer and benefit to combination administration of breast cancer.

Molecular subtype identification and prognosis stratification based on lysosome-related genes in breast cancer

Background

Lysosomes are known to have a significant impact on the development and recurrence of breast cancer. However, the association between lysosome-related genes (LRGs) and breast cancer remains unclear. This study aims to explore the potential role of LRGs in predicting the prognosis and treatment response of breast cancer.

Methods

Breast cancer gene expression profile data and clinical information were downloaded from TCGA and GEO databases, and prognosis-related LRGs were screened for consensus clustering analysis. Lasso Cox regression analysis was used to construct risk features derived from LRGs, and immune cell infiltration, immune therapy response, drug sensitivity, and clinical pathological feature differences were evaluated for different molecular subtypes and risk groups. A nomogram based on risk features derived from LRGs was constructed and evaluated.

Results

Our study identified 176 differentially expressed LRGs that are associated with breast cancer prognosis. Based on these genes, we divided breast cancer into two molecular subtypes with significant prognostic differences. We also found significant differences in immune cell infiltration between these subtypes. Furthermore, we constructed a prognostic risk model consisting of 7 LRGs, which effectively divides breast cancer patients into high-risk and low-risk groups. Patients in the low-risk group have better prognostic characteristics, respond better to immunotherapy, and have lower sensitivity to chemotherapy drugs, indicating that the low-risk group is more likely to benefit from immunotherapy and chemotherapy. Additionally, the risk score based on LRGs is significantly correlated with immune cell infiltration, including CD8 T cells and macrophages. This risk score model, along with age, chemotherapy, clinical stage, and N stage, is an independent prognostic factor for breast cancer. Finally, the nomogram composed of these factors has excellent performance in predicting overall survival of breast cancer.

Conclusions

In conclusion, this study has constructed a novel LRG-derived breast cancer risk feature, which performs well in prognostic prediction when combined with clinical pathological features.

Stem-like progenitor and terminally differentiated TFH-like CD4+ T cell exhaustion in the tumor microenvironment

Immune checkpoint inhibitors exert clinical efficacy against various types of cancer through reinvigoration of exhausted CD8+ T cells that attack cancer cells directly in the tumor microenvironment (TME). Using single-cell sequencing and mouse models, we show that CXCL13, highly expressed in tumor-infiltrating exhausted CD8+ T cells, induces CD4+ follicular helper T (TFH) cell infiltration, contributing to anti-tumor immunity. Furthermore, a part of the TFH cells in the TME exhibits cytotoxicity and directly attacks major histocompatibility complex-II-expressing tumors. TFH-like cytotoxic CD4+ T cells have high LAG-3/BLIMP1 and low TCF1 expression without self-renewal ability, whereas non-cytotoxic TFH cells express low LAG-3/BLIMP1 and high TCF1 with self-renewal ability, closely resembling the relationship between terminally differentiated and stem-like progenitor exhaustion in CD8+ T cells, respectively. Our findings provide deep insights into TFH-like CD4+ T cell exhaustion with helper progenitor and cytotoxic differentiated functions, mediating anti-tumor immunity orchestrally with CD8+ T cells.

Clinical Relevance of Tumour-Infiltrating Immune Cells in HER2-Negative Breast Cancer Treated with Neoadjuvant Therapy

Currently, therapy response cannot be accurately predicted in HER2-negative breast cancer (BC). Measuring stromal tumour-infiltrating lymphocytes (sTILs) and mediators of the tumour microenvironment and characterizing tumour-infiltrating immune cells (TIICs) may improve treatment response in the neoadjuvant setting. Tumour tissue and peripheral blood samples were retrospectively collected from 118 patients, and sTILs were evaluated. Circulating exosomes and myeloid-derived suppressor cells were determined by flow cytometry. TIICs markers (CD4, CD8, CD20, CD1a, and CD68) were assessed immunohistochemically. High sTILs were significantly associated with pathological complete response (pCR; p = 0.048) and event-free survival (EFS; p = 0.027). High-CD68 cells were significantly associated with pCR in triple-negative (TN, p = 0.027) and high-CD1a cells with EFS in luminal-B (p = 0.012) BC. Cluster analyses of TIICs revealed two groups of tumours (C1 and C2) that had different immune patterns and clinical outcomes. An immunoscore based on clinicopathological variables was developed to identify high risk (C1) or low-risk (C2) patients. Additionally, cluster analyses revealed two groups of tumours for both luminal-B and TNBC. Our findings support the association of sTILs with pCR and show an immunological component in a subset of patients with HER2-negative BC. Our immunoscore may be useful for future escalation or de-escalation treatments.

Endothelial cells in tumor microenvironment: insights and perspectives

The tumor microenvironment is a highly complex and dynamic mixture of cell types, including tumor, immune and endothelial cells (ECs), soluble factors (cytokines, chemokines, and growth factors), blood vessels and extracellular matrix. Within this complex network, ECs are not only relevant for controlling blood fluidity and permeability, and orchestrating tumor angiogenesis but also for regulating the antitumor immune response. Lining the luminal side of vessels, ECs check the passage of molecules into the tumor compartment, regulate cellular transmigration, and interact with both circulating pathogens and innate and adaptive immune cells. Thus, they represent a first-line defense system that participates in immune responses. Tumor-associated ECs are involved in T cell priming, activation, and proliferation by acting as semi-professional antigen presenting cells. Thus, targeting ECs may assist in improving antitumor immune cell functions. Moreover, tumor-associated ECs contribute to the development at the tumor site of tertiary lymphoid structures, which have recently been associated with enhanced response to immune checkpoint inhibitors (ICI). When compared to normal ECs, tumor-associated ECs are abnormal in terms of phenotype, genetic expression profile, and functions. They are characterized by high proliferative potential and the ability to activate immunosuppressive mechanisms that support tumor progression and metastatic dissemination. A complete phenotypic and functional characterization of tumor-associated ECs could be helpful to clarify their complex role within the tumor microenvironment and to identify EC specific drug targets to improve cancer therapy. The emerging therapeutic strategies based on the combination of anti-angiogenic treatments with immunotherapy strategies, including ICI, CAR T cells and bispecific antibodies aim to impact both ECs and immune cells to block angiogenesis and at the same time to increase recruitment and activation of effector cells within the tumor.

A gene signature of cancer-associated fibroblasts predicts prognosis and treatment response in bladder cancer

OBJECTIVE

Due to the pivotal role cancer-associated fibroblasts (CAFs) play in tumor progression, our study aimed to develop a signature of CAFs-related gene (CRG) to predict the survival outcomes and treatment response of bladder cancer (BLCA).

METHODS

The transcriptome data and relevant clinical information about BLCA were collected from publicly available databases, including The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets. Weighted gene co-expression network analysis was utilized to uncover CAFs-associated hub genes, and subsequently, a risk model for survival prognosis was constructed using LASSO-Cox regression. The immune microenvironment, immune infiltration, immunotherapy response, and drug sensitivity were explored using ESTIMATE, CIBERSORT, TIDE, and oncoPredict algorithms. To verify the expression of the CRGs, additional analyses were performed using online databases (HPA, CCLE, TIMER, cBioPortal, and TISCH).

RESULTS

Our study developed a CRG signature and constructed a prognostic model. Significant differences in overall survival were observed between the two risk stratifications. The risk score increased with the infiltration of CAFs and tumor staging progression, while closely correlating with immune checkpoint expression and infiltration of CD8 T cells, follicular helper T cells, regulatory T cells, activated dendritic cells, M0 macrophages, M2 macrophages, and resting mast cells. Furthermore, a higher proportion of patients in the low-risk stratification exhibited responsiveness to immunotherapy, and significant variances in sensitivity to multiple chemotherapy medications were observed between the two risk stratifications.

CONCLUSION

The construction of the risk model based on the CRG signature offers new avenues for the prognosis evaluation and development of personalized treatment strategies for BLCA.

Translational and oncologic significance of tertiary lymphoid structures in pancreatic adenocarcinoma

Pancreatic adenocarcinoma (PDAC) is an aggressive tumor with poor survival and limited treatment options. PDAC resistance to immunotherapeutic strategies is multifactorial, but partially owed to an immunosuppressive tumor immune microenvironment (TiME). However, the PDAC TiME is heterogeneous and harbors favorable tumor-infiltrating lymphocyte (TIL) populations. Tertiary lymphoid structures (TLS) are organized aggregates of immune cells that develop within non-lymphoid tissue under chronic inflammation in multiple contexts, including cancers. Our current understanding of their role within the PDAC TiME remains limited; TLS are complex structures with multiple anatomic features such as location, density, and maturity that may impact clinical outcomes such as survival and therapy response in PDAC. Similarly, our understanding of methods to manipulate TLS is an actively developing field of research. TLS may function as anti-tumoral immune niches that can be leveraged as a therapeutic strategy to potentiate both existing chemotherapeutic regimens and potentiate future immune-based therapeutic strategies to improve patient outcomes. This review seeks to cover anatomy, relevant features, immune effects, translational significance, and future directions of understanding TLS within the context of PDAC.

Leptin/lipopolysaccharide-treated dendritic cell vaccine improved cellular immune responses in an animal model of breast cancer

PURPOSE

In dendritic cells (DCs), leptin as an immune-regulating hormone, increases the IL-12 generation whereas it reduces the IL-10 production, thus contributing to TH1 cell differentiation. Using a murine model of breast cancer (BC), we evaluated the impacts of the Leptin and/or lipopolysaccharide (LPS)-treated DC vaccine on various T-cell-related immunological markers.

MATERIALS AND METHODS

Tumors were established in mice by subcutaneously injecting 7 × 105 4T1 cells into the right flank. Mice received the DC vaccines pretreated with Leptin, LPS, and both Leptin/LPS, on days 12 and 19 following tumor induction. The animals were sacrificed on day 26 and after that the frequency of the splenic cytotoxic T lymphocytes (CTLs) and TH1 cells; interferon gamma (IFN-γ), interleukin 12 (IL-12) and tumor growth factor beta (TGF-β) generation by tumor lysate-stimulated spleen cells, and the mRNA expression of T-bet, FOXP3 and Granzyme B in the tumors were measured with flow cytometry, ELISA and real-time PCR methods, respectively.

RESULTS

Leptin/LPS-treated mDC group was more efficient in blunting tumor growth (p = .0002), increasing survival rate (p = .001), and preventing metastasis in comparison with the untreated tumor-bearing mice (UT-control). In comparison to the UT-control group, treatment with Leptin/LPS-treated mDC also significantly increased the splenic frequencies of CTLs (p < .001) and TH1 cells (p < .01); promoted the production of IFN-γ (p < .0001) and IL-12 (p < .001) by splenocytes; enhanced the T-bet (p < .05) and Granzyme B (p < .001) expression, whereas decreased the TGF-β and FOXP3 expression (p < .05).

CONCLUSION

Compared to the Leptin-treated mDC and LPS-treated mDC vaccines, the Leptin/LPS-treated mDC vaccine was more effective in inhibiting BC development and boosting immune responses against tumor.

Breast Cancer Immunity: It is TIME for the Next Chapter

Our ability to interrogate the tumor immune microenvironment (TIME) at an ever-increasing granularity has uncovered critical determinants of disease progression. Not only do we now have a better understanding of the immune response in breast cancer, but it is becoming possible to leverage key mechanisms to effectively combat this disease. Almost every component of the immune system plays a role in enabling or inhibiting breast tumor growth. Building on early seminal work showing the involvement of T cells and macrophages in controlling breast cancer progression and metastasis, single-cell genomics and spatial proteomics approaches have recently expanded our view of the TIME. In this article, we provide a detailed description of the immune response against breast cancer and examine its heterogeneity in disease subtypes. We discuss preclinical models that enable dissecting the mechanisms responsible for tumor clearance or immune evasion and draw parallels and distinctions between human disease and murine counterparts. Last, as the cancer immunology field is moving toward the analysis of the TIME at the cellular and spatial levels, we highlight key studies that revealed previously unappreciated complexity in breast cancer using these technologies. Taken together, this article summarizes what is known in breast cancer immunology through the lens of translational research and identifies future directions to improve clinical outcomes.

Analysis of Immune Resistance Mechanisms in TNBC: Dual Effects Inside and Outside the Tumor

Triple-negative breast cancer (TNBC) is a unique subtype of breast cancer characterized by the lack of expression of the estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2. TNBC exhibits a high degree of aggressiveness, metastatic potential, and a poor prognosis. Despite the limited success of conventional treatments, immune checkpoint inhibitors (ICIs) have emerged as promising therapeutics for TNBC. Therefore, understanding the mechanisms underlying innate and acquired resistance to ICIs in TNBC is essential. Numerous studies suggest that intrinsic and extrinsic factors significantly contribute to the development of ICI resistance in TNBC. Intrinsic resistance may result from alterations in tumor-intrinsic signaling pathways, such as dysregulation of interferon (IFN) signaling or other signaling pathways. In contrast, extratumoral mechanisms may develop due to alterations in the tumor microenvironment, changes in T cell-related factors or adaptations within the immune system itself. In this paper, we endeavor to elucidate the underlying mechanisms of immune resistance by systematically examining immune mechanisms, the present state of immunotherapy, and the processes of immune resistance. Nonetheless, enhancing our understanding of the mechanisms underlying intratumoral and extratumoral resistance to ICIs in TNBC is crucial for optimizing patient outcomes in this challenging disease. Persistent efforts to identify novel targets for combination therapies, biomarkers that can predict the response to immunotherapy, and resistance mechanisms will be instrumental in achieving this objective.

Reviewing the significance of dendritic cell vaccines in interrupting breast cancer development

Breast cancer is a heterogeneous disease and is the most prevalent cancer in women. According to the U.S breast cancer statistics, about 1 in every 8 women develop an invasive form of breast cancer during their lifetime. Immunotherapy has been a significant advancement in the treatment of cancer with multiple studies reporting favourable patient outcomes by modulating the immune response to cancer cells. Here, we review the significance of dendritic cell vaccines in treating breast cancer patients. We discuss the involvement of dendritic cells and oncodrivers in breast tumorigenesis, highlighting the rationale for targeting oncodrivers and neoantigens using dendritic cell vaccine therapy. We review different dendritic cell subsets and maturation states previously used to develop vaccines and suggest the use of DC vaccines for breast cancer prevention. Further, we highlight that the intratumoral delivery of type 1 dendritic cell vaccines in breast cancer patients activates tumor antigen-specific CD4+ T helper cell type 1 (Th1) cells, promoting an anti-tumorigenic immune response while concurrently blocking pro-tumorigenic responses. In summary, this review provides an overview of the current state of dendritic cell vaccines in breast cancer highlighting the challenges and considerations necessary for an efficient dendritic cell vaccine design in interrupting breast cancer development.

Epigenetic targets to enhance antitumor immune response through the induction of tertiary lymphoid structures

Tertiary lymphoid structures (TLS) are ectopic lymphoid aggregates found in sites of chronic inflammation such as tumors and autoimmune diseases. The discovery that TLS formation at tumor sites correlated with good patient prognosis has triggered extensive research into various techniques to induce their formation at the tumor microenvironment (TME). One strategy is the exogenous induction of specific cytokines and chemokine expression in murine models. However, applying such systemic chemokine expression can result in significant toxicity and damage to healthy tissues. Also, the TLS formed from exogenous chemokine induction is heterogeneous and different from the ones associated with favorable prognosis. Therefore, there is a need to optimize additional approaches like immune cell engineering with lentiviral transduction to improve the TLS formation in vivo. Similarly, the genetic and epigenetic regulation of the different phases of TLS neogenesis are still unknown. Understanding these molecular regulations could help identify novel targets to induce tissue-specific TLS in the TME. This review offers a unique insight into the molecular checkpoints of the different stages and mechanisms involved in TLS formation. This review also highlights potential epigenetic targets to induce TLS neogenesis. The review further explores epigenetic therapies (epi-therapy) and ongoing clinical trials using epi-therapy in cancers. In addition, it builds upon the current knowledge of tools to generate TLS and TLS phenotyping biomarkers with predictive and prognostic clinical potential.

Expression analysis of lymphocyte subsets and lymphocyte-to-monocyte ratio: reveling immunosuppression and chronic inflammation in breast cancer

OBJECTIVE

To explore the immune status and chronic inflammation of breast cancer patients, this study aims to analyze the diagnostic value of peripheral blood lymphocyte subsets (CD3+T, CD4+T, CD8+T, CD3+CD4-CD8-T, CD19+B, and NK cells) and lymphocyte-to-monocyte ratio (LMR) for breast cancer. Furthermore, it seeks to examine the correlation between these subsets and LMR with clinicopathological features.

METHODS

A total of 100 breast cancer patients were selected as the experimental group, while 55 patients with benign breast diseases were included in the control group. Statistical analysis, including the Wilcoxon test, Kruskal-Wallis test and the receiver operating characteristic curve, was employed to investigate the association between these serum indexes and the clinicopathological characteristics of the patients.

RESULTS

The levels of CD3+T cells, CD4+T cells, CD8+T cells, CD4+/CD8+ ratio, NK cells, CD3+CD4-CD8-T cells, and LMR were found to be related to the occurrence of breast cancer when analyzing data from patients with benign and malignant breast diseases. Among these biomarkers, CD3+T cells, CD4+T cells, CD4+/CD8+ ratio, CD3+CD4-CD8-T cells, and LMR were identified as independent risk factors for breast cancer development, and the AUCs were 0.760, 0.750, 0.598, 0.697, and 0.761 (P < 0.05), respectively. Furthermore, we observed varying degrees of differences in the expression of CD3+T cells, CD4+T cells, CD8+T cells, CD4+/CD8+ ratio, and LMR in lymph node metastasis, clinical staging, molecular typing, Ki-67 level (P < 0.05). However, statistical differences in histologic grade and pathology type were not found (P ≥ 0.05).

CONCLUSION

Lymphocyte subsets and LMR reflect the immune status and chronic inflammation of the body, respectively. They have certain value in the diagnosis of benign and malignant breast diseases, and correlate with lymph node metastasis, clinical staging, molecular typing and other clinicopathological features of breast cancer. Therefore, monitoring the expression of lymphocyte subsets and LMR in the body may help the auxiliary diagnosis and condition analysis of breast cancer in the clinic.

The Emerging Role of Tertiary Lymphoid Structures in Breast Cancer: A Narrative Review

This narrative review aims to clarify the role of tertiary lymphoid structures in breast cancer. We examine their development, composition, and prognostic value, and current ways of recognizing them. A comprehensive literature review was performed using the PubMed/Medline, Scopus, and EMBASE databases. A significant area of interest in breast cancer research involves targeting immune checkpoint molecules, particularly in the triple-negative subtype, where treatment options remain limited. However, existing biomarkers have limitations in accurately predicting treatment response. In this context, tertiary lymphoid structures (TLSs) emerge as a prognostic biomarker and also as a promising predictive marker for response. TLSs are ectopic lymphoid formations or neo-organogenesis that can develop after prolonged exposure to inflammatory signals mediated by chemokines and cytokines. Their presence is inversely correlated with estrogen receptor (ER) and/or progesterone receptor (PR) expression, but positively associated with a higher pathologic complete response rate and improved overall survival. In certain scenarios, TLS-positive tumors were associated with improved outcomes regardless of the presence of PDL-1 (programmed cell death ligand 1) expression or TILs (tumor-infiltrating lymphocytes).

Single-cell and spatial profiling identify three response trajectories to pembrolizumab and radiation therapy in triple negative breast cancer

Strategies are needed to better identify patients that will benefit from immunotherapy alone or who may require additional therapies like chemotherapy or radiotherapy to overcome resistance. Here we employ single-cell transcriptomics and spatial proteomics to profile triple negative breast cancer biopsies taken at baseline, after one cycle of pembrolizumab, and after a second cycle of pembrolizumab given with radiotherapy. Non-responders lack immune infiltrate before and after therapy and exhibit minimal therapy-induced immune changes. Responding tumors form two groups that are distinguishable by a classifier prior to therapy, with one showing high major histocompatibility complex expression, evidence of tertiary lymphoid structures, and displaying anti-tumor immunity before treatment. The other responder group resembles non-responders at baseline and mounts a maximal immune response, characterized by cytotoxic T cell and antigen presenting myeloid cell interactions, only after combination therapy, which is mirrored in a murine model of triple negative breast cancer.

Multi-resolution deep learning characterizes tertiary lymphoid structures and their prognostic relevance in solid tumors

BACKGROUND

Tertiary lymphoid structures (TLSs) are dense accumulations of lymphocytes in inflamed peripheral tissues, including cancer, and are associated with improved survival and response to immunotherapy in various solid tumors. Histological TLS quantification has been proposed as a novel predictive and prognostic biomarker, but lack of standardized methods of TLS characterization hampers assessment of TLS densities across different patients, diseases, and clinical centers.

METHODS

We introduce an approach based on HookNet-TLS, a multi-resolution deep learning model, for automated and unbiased TLS quantification and identification of germinal centers in routine hematoxylin and eosin stained digital pathology slides. We developed HookNet-TLS using n = 1019 manually annotated TCGA slides from clear cell renal cell carcinoma, muscle-invasive bladder cancer, and lung squamous cell carcinoma.

RESULTS

Here we show that HookNet-TLS automates TLS quantification across multiple cancer types achieving human-level performance and demonstrates prognostic associations similar to visual assessment.

CONCLUSIONS

HookNet-TLS has the potential to be used as a tool for objective quantification of TLS in routine H&E digital pathology slides. We make HookNet-TLS publicly available to promote its use in research.

Prognostic value of tertiary lymphoid structures (TLS) in digestive system cancers: a systematic review and meta-analysis

BACKGROUND

Existing literature suggests that tertiary lymphatic structure (TLS) is associated with the progression of cancer. However, the prognostic role of TLS in digestive system cancers remains controversial. This meta-analysis aims to synthesize currently available evidence in the association between TLS and the survival of digestive system cancers.

METHODS

We systematically searched three digital databases (PubMed, Embase, Web of Science) for articles published from database inception to December 23, 2022. Study selection criteria are based on PECO framework: P (population: patients with digestive system cancers), E (exposure: presence of TLS), C (comparator: absence of TLS), O (outcome: overall survival, OS; recurrence-free survival, RFS; disease-free survival, DFS). The Quality in Prognostic Studies (QUIPS) tool was used to assess risk of bias for included studies. The study protocol was registered with PROSPERO (CRD42023416307).

RESULTS

A total of 25 studies with 6910 patients were included into the final meta-analysis. Random-effects models revealed that the absence of TLS was associated with compromised OS, RFS, and DFS of digestive system cancers, with pooled hazard ratios (HRs) of 1.74 (95% CI: 1.50-2.03), 1.96 (95% CI: 1.58-2.44), and 1.81 (95% CI: 1.49-2.19), respectively. Subgroup analyses disclosed a stronger TLS-survival association for pancreatic cancer, compared with other digestive system cancers.

CONCLUSION

TLS may be of prognostic significance for digestive system cancers. More original studies are needed to further corroborate this finding.

Tumor infiltrating lymphocytes (TILs) are a prognosis biomarker in Colombian patients with triple negative breast cancer

Triple negative breast cancer (TNBC) is highly immunogenic and high levels of tumor infiltrating lymphocytes (TILs) have been associated with a better prognosis and higher probability to achieve pathological complete response. Here, we explore the potential role of stromal TILs level and composition as a prognostic and predictive biomarker in TNBC. 195 Tumor biospecimens from patients diagnosed with TNBC were included. Stromal TILs (sTILs), positive CD4/CD8 cells were evaluated. Differences in clinic-pathological characteristics according to immune infiltration were assessed. The predictive and prognostic value of immune infiltration was analyzed by multivariate models. Higher immune infiltration was observed in patients with favorable clinical-pathological features. Survival analysis showed that longer overall survival times were observed in patients with a higher infiltration of sTILs (p = 0.00043), CD4 + (p = 0.0074) and CD8 + (p = 0.008). In the multivariate analysis, low levels of sTILs were found to be associated with a higher mortality hazard (HR: 1.59, 95% CI 1.01-2.48). CD4 and CD8 immune infiltration were associated with higher odds for pathological complete response (OR: 1.20, 95% CI 1.00-1.46, OR: 1.28, 1.02-1.65, respectively). Our results suggest that immune infiltration could be used as a prognostic marker for overall survival in TNBC patients.

Immunotherapy-related biomarkers: Confirmations and uncertainties

Immunotherapy profoundly changed oncology treatment, becoming one of the main therapeutical strategies. Remarkable improvement has been achieved in survival outcomes, but the percentage of patients who benefit from immunotherapy is still limited. Only one-third of patients receiving immune checkpoint inhibitors (ICIs) achieve long-term response. Several patients are not responsive to treatment or relapse after an initial response. To date, programmed death-ligand 1, microsatellite instability, and tumor mutational burden are the three biomarkers validated to predict the ICIs response, but a single variable seems still insufficient in the patient's selection. Considering the substantial and increasing use of these drugs, the identification of new predictive biomarkers of ICI response is of paramount importance. We summarize the state of the art and the clinical use of immune biomarkers in oncology, highlighting the strength and weaknesses of currently approved biomarkers, describing the emerging tissues and circulating biomarkers, and outlining future perspectives.

Canonical Kaiso target genes define a functional signature that associates with breast cancer survival and the invasive lobular carcinoma histological type

Invasive lobular carcinoma (ILC) is a low- to intermediate-grade histological breast cancer type caused by mutational inactivation of E-cadherin function, resulting in the acquisition of anchorage independence (anoikis resistance). Most ILC cases express estrogen receptors, but options are limited in relapsed endocrine-refractory disease as ILC tends to be less responsive to standard chemotherapy. Moreover, ILC can relapse after >15 years, an event that currently cannot be predicted. E-cadherin inactivation leads to p120-catenin-dependent relief of the transcriptional repressor Kaiso (ZBTB33) and activation of canonical Kaiso target genes. Here, we examined whether an anchorage-independent and ILC-specific transcriptional program correlated with clinical parameters in breast cancer. Based on the presence of a canonical Kaiso-binding consensus sequence (cKBS) in the promoters of genes that are upregulated under anchorage-independent conditions, we defined an ILC-specific anoikis resistance transcriptome (ART). Converting the ART genes into human orthologs and adding published Kaiso target genes resulted in the Kaiso-specific ART (KART) 33-gene signature, used subsequently to study correlations with histological and clinical variables in primary breast cancer. Using publicly available data for ERPOS Her2NEG breast cancer, we found that expression of KART was positively associated with the histological ILC breast cancer type (p < 2.7E-07). KART expression associated with younger patients in all invasive breast cancers and smaller tumors in invasive ductal carcinoma of no special type (IDC-NST) (<2 cm, p < 6.3E-10). We observed associations with favorable long-term prognosis in both ILC (hazard ratio [HR] = 0.51, 95% CI = 0.29-0.91, p < 3.4E-02) and IDC-NST (HR = 0.79, 95% CI = 0.66-0.93, p < 1.2E-04). Our analysis thus defines a new mRNA expression signature for human breast cancer based on canonical Kaiso target genes that are upregulated in E-cadherin deficient ILC. The KART signature may enable a deeper understanding of ILC biology and etiology. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Association of systemic inflammatory markers and tertiary lymphoid structure with pathological complete response in gastric cancer patients receiving preoperative treatment: a retrospective cohort study

BACKGROUND

Assessment of systemic and local immune responses is crucial in determining the efficacy of cancer interventions. The identification of specific factors that correlate with pathological complete response (pCR) is essential for optimizing treatment decisions.

METHODS

In this retrospective study, a total of 521 patients diagnosed with gastric adenocarcinoma who underwent curative gastrectomy following preoperative treatment were reviewed. Of these patients, 463 did not achieve pCR (non-pCR) and 58 achieved pCR. Clinicopathological factors were evaluated to identify predictors for pCR using a logistic regression model. Additionally, a smaller cohort (n=76) was derived using propensity score matching to investigate local immune response, specifically the features of tertiary lymphoid structure (TLS) using H&E staining, immunohistochemistry, and multiplex immunofluorescence.

RESULTS

The multivariate regression analysis demonstrated a significant association between low systemic inflammatory status and pCR, as evidenced by reduced levels of the combined systemic immune-inflammation index (SII) and neutrophil-to-lymphocyte ratio (NLR) (SII+NLR) (odds ratio: 3.33, 95% CI: 1.79-6.17, P<0.001). In the smaller cohort analysis, distinct TLS characteristics were correlated with the presence of pCR. Specifically, a higher density of TLS and a lower proportion of PD1+ cells and CD8+ cells within TLS in the tumor bed were strongly associated with pCR.

CONCLUSION

Both systemic and local immune profile were associated with pCR. A low level of SII+NLR served as an independent predictor of pCR, while distinct TLS features were associated with the presence of pCR. Focusing on the immune profile was crucial for optimal management of gastric cancer patients receiving preoperative treatment.

Characterisation of luminal and triple-negative breast cancer with HER2 Low protein expression

BACKGROUND

Breast cancer (BC) expressing low levels of human epidermal growth factor receptor 2 (HER2 Low) is an emerging category that needs further refining. This study aims to provide a comprehensive clinico-pathological and molecular profile of HER2 Low BC including response to therapy and patient outcome in the adjuvant and neoadjuvant settings.

METHODS

Two different independent and well-characterised BC cohorts were included. Nottingham cohort (A) (n = 5744) and The Cancer Genome Atlas (TCGA) BC cohort (B) (n = 854). The clinical, molecular, biological and immunological profile of HER2 Low BC was investigated. Transcriptomic and pathway enrichment analyses were performed on the TCGA BC cohort and validated through next-generation sequencing in a subset of Nottingham cases.

RESULTS

Ninety percent of HER2 Low tumours were hormone receptor (HR) positive (HR+), enriched with luminal intrinsic molecular subtype, lacking significant expression of HER2 oncogenic signalling genes and of favourable clinical behaviour compared to HER2 negative (HER2-) BC. In HR+ BC, no significant prognostic differences were detected between HER2 Low and HER2- tumours. However, in HR- BC, HER2 Low tumours were less aggressive with longer patient survival. Transcriptomic data showed that the majority of HR- /HER2 Low tumours were of luminal androgen receptor (LAR) intrinsic subtype, enriched with T-helper lymphocytes, activated dendritic cells and tumour associated neutrophils, while most HR-/HER2- tumours were basal-like, enriched with tumour associated macrophages.

CONCLUSION

HER2 Low BC is mainly driven by HR signalling in HR+ tumours. HR-/HER2 Low tumours tend to be enriched with LAR genes with a unique immune profile.

Radiogenomic analysis of cellular tumor-stroma heterogeneity as a prognostic predictor in breast cancer

BACKGROUND

The tumor microenvironment and intercellular communication between solid tumors and the surrounding stroma play crucial roles in cancer initiation, progression, and prognosis. Radiomics provides clinically relevant information from radiological images; however, its biological implications in uncovering tumor pathophysiology driven by cellular heterogeneity between the tumor and stroma are largely unknown. We aimed to identify radiogenomic signatures of cellular tumor-stroma heterogeneity (TSH) to improve breast cancer management and prognosis analysis.

METHODS

This retrospective multicohort study included five datasets. Cell subpopulations were estimated using bulk gene expression data, and the relative difference in cell subpopulations between the tumor and stroma was used as a biomarker to categorize patients into good- and poor-survival groups. A radiogenomic signature-based model utilizing dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was developed to target TSH, and its clinical significance in relation to survival outcomes was independently validated.

RESULTS

The final cohorts of 1330 women were included for cellular TSH biomarker identification (n = 112, mean age, 57.3 years ± 14.6) and validation (n = 886, mean age, 58.9 years ± 13.1), radiogenomic signature of TSH identification (n = 91, mean age, 55.5 years ± 11.4), and prognostic (n = 241) assessments. The cytotoxic lymphocyte biomarker differentiated patients into good- and poor-survival groups (p < 0.0001) and was independently validated (p = 0.014). The good survival group exhibited denser cell interconnections. The radiogenomic signature of TSH was identified and showed a positive association with overall survival (p = 0.038) and recurrence-free survival (p = 3 × 10-4).

CONCLUSION

Radiogenomic signatures provide insights into prognostic factors that reflect the imbalanced tumor-stroma environment, thereby presenting breast cancer-specific biological implications and prognostic significance.

A pan-cancer analysis of the role of argininosuccinate synthase 1 in human tumors

Aim

There is accumulating evidence indicating that ASS1 is closely related to tumors. No pan-cancer analysis of ASS1 was available.

Methods

Here we explored the gene expression and survival analysis of ASS1 across thirty-three tumors based on the datasets of the TCGA (Cancer Genome Atlas), the GEO (Gene Expression Omnibus), and the GEPIA2 (Gene Expression Profiling Interactive Analysis, version 2).

Results

ASS1 is highly expressed in most normal tissues and is related to the progression of some tumors. We also report ASS1 genetic alteration and their association with tumor prognosis and report differences in ASS1 phosphorylation sites between tumors and control normal tissues. ASS1 expression was associated with the infiltration of cancer-associated fibroblasts (CAFs) for the TCGA tumors of BRCA (Breast invasive carcinoma), CESC (Cervical squamous cell carcinoma and endocervical adenocarcinoma), COAD (Colon adenocarcinoma), ESCA (Esophageal carcinoma), SKCM (Skin cutaneous melanoma), SKCM-Metastasis, TGCT (Testicular germ cell tumors), and endothelial cell for the tumors of BRCA, BRCA-Basal, CESC, ESCA, KIRC (Kidney renal clear cell carcinoma), LUAD (Lung adenocarcinoma), LUSC (Lung squamous cell carcinoma), SKCM, SKCM-Metastasis, SKCM-Primary, STAD (Stomach adenocarcinoma), and TGCT. The KEGG and GO analysis were used to analyze ASS1-related signaling pathways. Finally, we used Huh7 cell line to verify the function of ASS1 in vitro. After ASS1 knockdown using small interfering RNA (siRNA), the proliferation and invasion of Huh7 were enhanced, cyclin D1 was up-regulated, and anti-apoptotic protein bax was down-regulated, suggesting that ASS1 is a tumor suppressor gene in hepatocellular carcinoma.

Conclusion

Our first pan-cancer study offers a relatively comprehensive understanding of the roles of ASS1 in different tumors.