T-cell-based breast cancer immunotherapy

Knowledge mapping of immunotherapy for breast cancer: A bibliometric analysis from 2013 to 2022

Breast cancer is the leading cause of cancer-related death among women globally. Immunotherapy has emerged as a major milestone in contemporary oncology. This study aims to conduct a bibliometric analysis in the field of immunotherapy for breast cancer, providing a comprehensive overview of the current research status, identifying trends and hotspots in research topics. We searched and retrieved data from the Web of Science Core Collection, and performed a bibliometric analysis of publications on immunotherapy for breast cancer from 2013 to 2022. Current status and hotspots were evaluated by co-occurrence analysis using VOSviewer. Evolution and bursts of knowledge base were assessed by co-citation analysis using CiteSpace. Thematic evolution by bibliometrix package was used to discover keywords trends. The attribution and collaboration of countries/regions, institutions and authors were also explored. A total of 7,975 publications were included. In co-occurrence analysis of keywords, 6 major clusters were revealed: tumor microenvironment, prognosis biomarker, immune checkpoints, novel drug delivery methods, immune cells and therapeutic approaches. The top three most frequently mentioned keywords were tumor microenvironment, triple-negative breast cancer, and programmed cell death ligand 1. The most productive country, institution and author were the USA (2926 publications), the University of Texas MD Anderson Cancer Center (219 publications), and Sherene Loi (28 publications), respectively. There has been a rapid growth in studies on immunotherapy for breast cancer worldwide. This research area has gained increasing attention from different countries and institutions. With the rising incidence of breast cancer, immunotherapy represents a research field of significant clinical value and potential.

Application of mesenchymal stem cells exosomes as nanovesicles delivery system in the treatment of breast cancer

As people's living standards continue to improve and human life span expectancy increases, the incidence and mortality rates of breast cancer are continuously rising. Early detection of breast cancer and targeted therapy for different breast cancer subtypes can significantly reduce the mortality rate and alleviate the suffering of patients. Exosomes are extracellular vesicles secreted by various cells in the body. They participate in physiological and pathological responses by releasing active substances and play an important role in regulating intercellular communication. In recent years, research on exosomes has gradually expanded, and their special membrane structure and targetable characteristics are being increasingly applied in various clinical studies. Mesenchymal stem cells (MSCs)-derived exosomes play an important role in regulating the progression of breast cancer. In this review, we summarize the current treatment methods for breast cancer, the connection between MSCs, exosomes, and breast cancer, as well as the application of exosomes derived from MSCs from different sources in cancer treatment. We highlight how the rational design of modified MSCs-derived exosomes (MSCs-Exos) delivery systems can overcome the uncertainties of stem cell therapy and overcome the clinical translation challenges of nanomaterials. This work aims to promote future research on the application of MSCs-Exos in breast cancer treatment.

Recent developments in immunotherapy for gastrointestinal tract cancers

The past few decades have witnessed the rise of immunotherapy for Gastrointestinal (GI) tract cancers. The role of immune checkpoint inhibitors (ICIs), particularly programmed death protein 1 (PD-1) and PD ligand-1 antibodies, has become increasingly pivotal in the treatment of advanced and perioperative GI tract cancers. Currently, anti-PD-1 plus chemotherapy is considered as first-line regimen for unselected advanced gastric/gastroesophageal junction adenocarcinoma (G/GEJC), mismatch repair deficient (dMMR)/microsatellite instability-high (MSI-H) colorectal cancer (CRC), and advanced esophageal cancer (EC). In addition, the encouraging performance of claudin18.2-redirected chimeric antigen receptor T-cell (CAR-T) therapy in later-line GI tract cancers brings new hope for cell therapy in solid tumour treatment. Nevertheless, immunotherapy for GI tumour remains yet precise, and researchers are dedicated to further maximising and optimising the efficacy. This review summarises the important research, latest progress, and future directions of immunotherapy for GI tract cancers including EC, G/GEJC, and CRC.

Circadian rhythms and breast cancer: unraveling the biological clock's role in tumor microenvironment and ageing

Breast cancer (BC) is one of the most common and fatal malignancies among women worldwide. Circadian rhythms have emerged in recent studies as being involved in the pathogenesis of breast cancer. In this paper, we reviewed the molecular mechanisms by which the dysregulation of the circadian genes impacts the development of BC, focusing on the critical clock genes, brain and muscle ARNT-like protein 1 (BMAL1) and circadian locomotor output cycles kaput (CLOCK). We discussed how the circadian rhythm disruption (CRD) changes the tumor microenvironment (TME), immune responses, inflammation, and angiogenesis. The CRD compromises immune surveillance and features and activities of immune effectors, including CD8+ T cells and tumor-associated macrophages, that are important in an effective anti-tumor response. Meanwhile, in this review, we discuss bidirectional interactions: age and circadian rhythms, aging further increases the risk of breast cancer through reduced vasoactive intestinal polypeptide (VIP), affecting suprachiasmatic nucleus (SCN) synchronization, reduced ability to repair damaged DNA, and weakened immunity. These complex interplays open new avenues toward targeted therapies by the combination of clock drugs with chronotherapy to potentiate the immune response while reducing tumor progression for better breast cancer outcomes. This review tries to cover the broad area of emerging knowledge on the tumor-immune nexus affected by the circadian rhythm in breast cancer.

Senescence-related genes analysis in breast cancer reveals the immune microenvironment and implications for immunotherapy

Despite the advent of precision therapy for breast cancer (BRCA) treatment, some individuals are still unable to benefit from it and have poor survival prospects as a result of the disease's high heterogeneity. Cell senescence plays a crucial role in the tumorigenesis, progression, and immune regulation of cancer and has a major impact on the tumor microenvironment. To find new treatment strategies, we aimed to investigate the potential significance of cell senescence in BRCA prognosis and immunotherapy. We created a 9-gene senescence-related signature. We evaluated the predictive power and the role of signatures in the immune microenvironment and infiltration. In vitro tests were used to validate the expression and function of the distinctive critical gene ACTC1. Our risk signature allows BRCA patients to receive a Predictive Risk Signature (PRS), which may be used to further categorize a patient's response to immunotherapy. Compared to conventional clinicopathological characteristics, PRS showed strong predictive efficacy and precise survival prediction. Moreover, PRS subgroups were examined for altered pathways, mutational patterns, and possibly useful medicines. Our research offers suggestions for incorporating senescence-based molecular classification into risk assessment and ICI therapy decision-making.

(Nano)platforms in breast cancer therapy: Drug/gene delivery, advanced nanocarriers and immunotherapy

Breast cancer is the most malignant tumor in women, and there is no absolute cure for it. Although treatment modalities including surgery, chemotherapy, and radiotherapy are utilized for breast cancer, it is still a life-threatening disease for humans. Nanomedicine has provided a new opportunity in breast cancer treatment, which is the focus of the current study. The nanocarriers deliver chemotherapeutic agents and natural products, both of which increase cytotoxicity against breast tumor cells and prevent the development of drug resistance. The efficacy of gene therapy is boosted by nanoparticles and the delivery of CRISPR/Cas9, Noncoding RNAs, and RNAi, promoting their potential for gene expression regulation. The drug and gene codelivery by nanoparticles can exert a synergistic impact on breast tumors and enhance cellular uptake via endocytosis. Nanostructures are able to induce photothermal and photodynamic therapy for breast tumor ablation via cell death induction. The nanoparticles can provide tumor microenvironment remodeling and repolarization of macrophages for antitumor immunity. The stimuli-responsive nanocarriers, including pH-, redox-, and light-sensitive, can mediate targeted suppression of breast tumors. Besides, nanoparticles can provide a diagnosis of breast cancer and detect biomarkers. Various kinds of nanoparticles have been employed for breast cancer therapy, including carbon-, lipid-, polymeric- and metal-based nanostructures, which are different in terms of biocompatibility and delivery efficiency.

Synergistic efficacy of PI3Kδ inhibitor with anti-PD-1 mAbs in immune-humanized PDX model of endocrine resistance hormone receptor-positive advanced breast cancer

Purpose

Endocrine resistance hormone receptor-positive (HR+) advanced breast cancer (ABC) is generally insensitive to immunecheckpoint inhibitors (ICIs). This study sought to determine whether PI3Kδ inhibitor could enhance the sensitivity of endocrine resistance HR + advanced BC to ICIs by reducing immune evasion.

Methods

Patient-derived HR + ABC xenografts were implanted into immune-humanized NSG mice and subsequently treated with YY20394 (PI3Kδ inhibitor) and camrelizumab. The mice were monitored for tumor progression, biochemical blood indicators, and peripheral blood T-cell subsets. The xenografted tumors were collected at the end of the treatment cycle and subjected to HE staining, immunohistochemistry and protein phosphorylation analysis. Besides, the xenografted tumors were also used to isolate primary breast cancer cells (BCCs) and regulatory T-cells (Tregs), which were subsequently used to evaluate drug sensitivity in vitro.

Results

The humanized PDX model showed a favorable initial treatment response to camrelizumab combined with YY20394 and manageable toxicity. YY20394 plus camrelizumab showed a strong inhibitory effect on HR + BC in vivo mediated by suppression of Treg activity and an increased proportion of CD8+ T cells. Mice bearing tumors treated with YY20394 and camrelizumab had less invasion, mitotic figures, and ki67 expression, while having higher IL-12 expression compared with other groups. Mechanistically, YY20394 only effectively inhibited the PI3K pathway and proliferation activity in Tregs but not in BCCs.

Conclusion

Our study suggests PI3Kδ inhibitor could the enhance the efficacy of ICIs in HR + BC PDX models by combating immune suppression and provides a feasible approach that may overcome the resistance of ICIs in HR + BC patients.

Challenges in the combination of radiotherapy and immunotherapy for breast cancer

INTRODUCTION

Immunotherapy (IT) is showing promise in the treatment of breast cancer, but IT alone only benefits a minority of patients. Radiotherapy (RT) is usually included in the standard of care for breast cancer patients and is traditionally considered as a local form of treatment. The emerging knowledge of RT-induced systemic immune response, and the observation that the rare abscopal effect of RT on distant cancer metastases can be augmented by IT, have increased the enthusiasm for combinatorial immunoradiotherapy (IRT) for breast cancer patients. However, IRT largely follows the traditional sole RT and IT protocols and does not consider patient specificity, although patients' responses to treatment remain heterogeneous.

AREAS COVERED

This review discusses the rationale of IRT for breast cancer, the current knowledge, challenges, and future directions.

EXPERT OPINION

The synergy between RT and the immune system has been observed but not well understood at the basic level. The optimal dosages, timing, target, and impact of biomarkers are largely unknown. There is an urgent need to design efficacious pre-clinical and clinical trials to optimize IRT for cancer patients, maximize the synergy of radiation and immune response, and explore the abscopal effect in depth, taking into account patients' personal features.

Comprehensively Analyze the Prognosis Significance and Immune Implication of PTPRO in Lung Adenocarcinoma

Immunotherapy for lung adenocarcinoma (LUAD) is considered to be a promising treatment option, but only a minority of patients benefit from it. Therefore, it is essential to clarify the regulation mechanism of the tumor immune microenvironment (TIM) of the LUAD. Receptor-type protein tyrosine phosphatase (PTPRO) has been shown to be a tumor suppressor in a variety of tumor; however, its role in LUAD has never been reported. In this study, we first found that PTPRO was lowly expressed in LUAD and positively correlated with patient prognosis. Next, we investigated the relationship between PTPRO and clinical characteristics, and the results showed that gender, age, T, and stage were closely related to the expression level of PTPRO. Moreover, we performed univariate and multivariate analyses, and the results revealed that PTPRO was a protective factor for LUAD. By constructing a nomogram based on the expression level of PTPRO and various clinical characteristics, it was proved that the nomogram has a good predictive capacity. Furthermore, we analyzed the coexpression network of PTPRO through multiple databases and performed GO and KEGG enrichment analyses. The results demonstrated that PTPRO was involved in the regulation of multiple immune pathways. In addition, we analyzed whether PTPRO expression of LUAD regulate immune cell infiltration and the results demonstrated that PTPRO was closely related to the infiltration of various immune cells. Finally, we predicted LUAD sensitivity to chemotherapeutics and response to immunotherapy by PTPRO expression levels. The results showed that PTPRO expression level affect the sensitivity of various chemotherapeutic drugs and may be involved in the efficacy of immunotherapy. These results we obtained suggested that PTPRO is closely related to the prognosis and TIM of LUAD, which may be a potential immunotherapeutic target for LUAD.

Innovative Therapeutic Approaches for Patients with HER2-Positive Breast Cancer

Overexpression of human epidermal growth factor receptor 2 (HER2), a transmembrane tyrosine kinase receptor, has been described in about 15-20% of breast cancer (BC) and is associated with poor outcomes. Trastuzumab is the first anti-HER2 monoclonal antibody (mAB) that blocks receptor activity but it also activates immune response against cancer cells, thus, revolutionizing the prognosis of patients with HER2-positive BC. Over the years, new therapies have been developed, including other mAbs and tyrosine kinase inhibitors (TKIs) that required multimodal approaches with chemotherapy to optimize their anticancer activity. This chapter gives a comprehensive overview of the last advancements including new approaches and future combinations, which seem to be very promising in overcoming resistance to the traditional anti-HER2 treatments. A modern therapeutic algorithm should include treatment options based on tumour patterns and a patient-centred approach. A proper patient's selection is crucial to derive maximal benefits from a treatment strategy and emerging biomarkers should be integrated along with the HER2 status, which is currently the only validated biomarker in the context of HER2-positive disease. These biomarkers might include molecular features with reported prognostic/predictive significance, such as phosphatidylinositol 3' -kinase (PI3K) or mitogen-activated protein kinase (MAPK) pathways, programmed cell death protein ligand 1 (PD-L1), and tumour-infiltrating lymphocytes (TILs), which all affect prognosis and response to treatments.

Landscape of prognosis and immunotherapy responsiveness under tumor glycosylation-related lncRNA patterns in breast cancer

Aberrant glycosylation, a post-translational modification of proteins, is regarded to engage in tumorigenesis and malignant progression of breast cancer (BC). The altered expression of glycosyltransferases causes abnormal glycan biosynthesis changes, which can serve as diagnostic hallmarks in BC. This study attempts to establish a predictive signature based on glycosyltransferase-related lncRNAs (GT-lncRNAs) in BC prognosis and response to immune checkpoint inhibitors (ICIs) treatment. We firstly screened out characterized glycosyltransferase-related genes (GTGs) through NMF and WGCNA analysis and identified GT-lncRNAs through co-expression analysis. By using the coefficients of 8 GT-lncRNAs, a risk score was calculated and its median value divided BC patients into high- and low-risk groups. The analyses unraveled that patients in the high-risk group had shorter survival and the risk score was an independent predictor of BC prognosis. Besides, the predictive efficacy of our risk score was higher than other published models. Moreover, ESTIMATE analysis, immunophenoscore (IPS), and SubMAP analysis showed that the risk score could stratify patients with distinct immune infiltration, and patients in the high-risk group might benefit more from ICIs treatment. Finally, the vitro assay showed that MIR4435-2HG might promote the proliferation and migration of BC cells, facilitate the polarization of M1 into M2 macrophages, enhance the migration of macrophages and increase the PD-1/PD-L1/CTLA4 expression. Collectively, our well-constructed prognostic signature with GT-lncRNAs had the ability to identify two subtypes with different survival state and responses to immune therapy, which will provide reliable tools for predicting BC outcomes and making rational follow-up strategies.

High FLT3 expression indicates favorable prognosis and correlates with clinicopathological parameters and immune infiltration in breast cancer

Purpose: Breast cancer is a highly heterogeneous malignancy, seriously threatening female health worldwide and inducing higher mortalities. Few have the studies evaluated Fms-like TyrosineKinase-3 (FLT3) in prognostic risk, immunotherapy or any other treatment of breast cancer. Our study focused on investigating the function of FLT3 in breast cancer.

Patients and methods: Based on transcriptome and methylation data mined from The Cancer Gene Atlas (TCGA), we explored the clinical features of FLT3 expression in 1079 breast cancer samples. RT-qPCR in cell lines and tissue samples was used to verify the expression difference of FLT3. Kaplan–Meier survival analysis and cox regression models were employed for screening of FLT3 with potential prognostic capacity. Subsequently, functional analysis of the co-expressed genes was conducted using Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and gene-set enrichment analysis (GSEA). The correlation between FLT3 expression and tumor immune infiltration was jointly analyzed with estimate, ssGSEA, TIMER, and TISIDB. Then we employed checkpoint-related molecules, immunophenoscore (IPS), and tumor mutation burden (TMB) to assess the efficacy of immuno-checkpoint inhibitors (ICIs). Pearson correlation coefficient was employed to exam the association between DNA methylation and FLT3 expression.

Results: FLT3 displays an elevated expression in breast cancer than normal pairs and is significantly associated with multiple clinical characteristics like age, menopause status, histological type, pathological stage, and molecular subtype as well as increased overall survival (OS). Additionally, FLT3 is a favorable independent prognostic factor. GO, KEGG, and GSEA suggested that FLT3 was associated with diversified immune-related features. FLT3 expression is correlated with the abundance of various immune cells namely CD4+T cell, CD8+ T cell, myeloid dendritic cell, and neutrophil as well as immune inhibitors especially CTLA4, which is positively correlated with FLT3 expression. Moreover, TMB displayed a negative correlation with FLT3 expression while IPS showed adverse tendency. Ultimately, the methylation of FLT3 downregulates the gene expression and closely binds to a few clinical parameters.

Conclusion: FLT3 can be used for prognostic prediction and is relevant to immune infiltration in breast cancer. FLT3 may pave the way for future novel immunotherapies.

Targeting breast cancer with a combination of DNT and LAG3 checkpoint blockage and its mechanism

INTRODUCTION

The characteristics of the tumor immune microenvironment (TIME) are closely related to immunotherapy. Breast cancer can benefit from immunotherapy, and its TIME is still unclear.

METHODS

We utilized mass cytometry to explore the immune cell heterogeneity in breast cancer. Double-negative T cells (DNTs) from healthy volunteers (HBs) were enriched in vitro. Flow cytometry was used to detect the cell surface receptors of cancer cells and DNT cells. The correlation between immune checkpoints and the abundance of immune cells or prognosis of breast cancer was analyzed by the TCGA database. The messenger RNA (mRNA) expression of functional genes was performed by quantitative real-time PCR.

RESULTS

We found that the frequencies of Granzyme B (GZMB)+ CD8+ T and GZMB+ DNT cells in cancer tissues (CA) of breast cancer were lower than those in blood samples of patients (PB), and the frequencies of programmed cell death protein 1 (PD1)+ CD8+ T and PD1+ DNT cells in CA were higher than those in PB. DNTs from HBs had a cytotoxic effect on MDA-MB-231. LAG3Ab could upregulate the mRNA expression of interferon gamma and perforin by increasing T-BET transcription to enhance the cytotoxicity of DNT cells in vitro.

CONCLUSION

Our study revealed the suppressive status of TIME in breast cancer and supported DNT cells had the potential to be applied as a novel adoptive cell therapy for TNBC either alone or combined with LAG3Ab.

Recent advances in biomaterial-assisted cell therapy

With the outstanding achievement of chimeric antigen receptor (CAR)-T cell therapy in the clinic, cell-based medicines have attracted considerable attention for biomedical applications and thus generated encouraging progress. As the basic construction unit of organisms, cells harbor low immunogenicity, desirable compatibility, and a strong capability of crossing various biological barriers. However, there is still a long way to go to fix significant bottlenecks for their clinical translation, such as facile preparation, strict stability requirements, scale-up manufacturing, off-target toxicity, and affordability. The rapid development of biotechnology and engineering approaches in materials sciences has provided an ideal platform to assist cell-based therapeutics for wide application in disease treatments by overcoming these issues. Herein, we survey the most recent advances of various cells as bioactive ingredients and outline the roles of biomaterials in developing cell-based therapeutics. Besides, a perspective of cell therapies is offered with a particular focus on biomaterial-involved development of cell-based biopharmaceuticals.

Targeting Metabolic Reprogramming of T-Cells for Enhanced Anti-Tumor Response

Cancer immunotherapy is an effective treatment option against cancer. One of the approaches of cancer immunotherapy is the modification of T cell-based anti-tumor immune responses. T-cells, a type of adaptive immune response cells responsible for cell-mediated immunity, have long been recognized as key regulators of immune-mediated anti-tumor immunity. T-cell activities have been reported to be suppressed or enhanced by changes in cell metabolism. Moreover, metabolic reprogramming during activation of T cells is required for the development of distinct differentiation profiles of these cells, which may allow the development of long-term cell-mediated anti-tumor immunity. However, T cells have been shown to undergo metabolic exhaustion in tumor microenvironment (TME) as it poses several obstacles to their function. Applications of several mechanistic solutions to improve the efficacy of T cell-based therapies including chimeric antigen receptor (CAR) T cell therapy are yet to be determined. Modifying the metabolic properties of these cells and employing them in cancer immunotherapy is a potential strategy for improving their anti-tumor activity and therapeutic efficacy. To give an insight, in this review paper, we endeavoured to cover metabolic reprogramming in cancer and T cells, signalling mechanisms involved in immuno-metabolic regulation, the effects of the TME on T cell metabolic fitness, and targeting metabolic reprogramming of T cells for an enhanced anti-tumor response.

Gene Expression Profiling in Early Breast Cancer-Patient Stratification Based on Molecular and Tumor Microenvironment Features

Patients with early-stage hormone receptor-positive, human epidermal growth factor receptor 2-negative (HER2−) breast cancer (BC) are typically treated with surgery, followed by adjuvant systemic endocrine therapy with or without adjuvant chemotherapy and radiation therapy. Current guidelines regarding the use of adjuvant systemic therapy depend on clinical and pathological factors, such as the morphological assessment of tumor subtype; histological grade; tumor size; lymphovascular invasion; and lymph node status combined with estrogen receptor, progesterone receptor, and HER2 biomarker profiles assessed using immunohistochemistry and in situ hybridization. Additionally, the prognostic and predictive value of tumor-infiltrating lymphocytes and their composition is emerging as a key marker in triple negative (TNBC) and HER2-enriched molecular breast tumor subtypes. However, all these factors do not necessarily reflect the molecular heterogeneity and complexity of breast cancer. In the last two decades, gene expression signatures or profiling (GEP) tests have been developed to predict the risk of disease recurrence and estimate the potential benefit of receiving adjuvant systemic chemotherapy in patients with luminal breast cancer. GEPs have been utilized to help physicians to refine decision-making process, complementing clinicopathological parameters, and can now be used to classify the risk of recurrence and tailoring personalized treatments. Several clinical trials using GEPs validate the increasing value of such assays in different clinical settings, addressing relevant clinical endpoints. Finally, the recent approval of immune checkpoint inhibitors in TNBC and the increasing use of immunotherapy in different molecular BC populations highlight the opportunity to refine current GEPs by including a variety of immune-related genes that may help to improve predicting drug response and finetune prognosis.

Licorice extract inhibits growth of non-small cell lung cancer by down-regulating CDK4-Cyclin D1 complex and increasing CD8+ T cell infiltration

Background

Targeting tumor microenvironment (TME) may provide therapeutic activity and selectivity in treating cancers. Therefore, an improved understanding of the mechanism by which drug targeting TME would enable more informed and effective treatment measures. Glycyrrhiza uralensis Fisch (GUF, licorice), a widely used herb medicine, has shown promising immunomodulatory activity and anti-tumor activity. However, the molecular mechanism of this biological activity has not been fully elaborated.

Methods

Here, potential active compounds and specific targets of licorice that trigger the antitumor immunity were predicted with a systems pharmacology strategy. Flow cytometry technique was used to detect cell cycle profile and CD8⁺ T cell infiltration of licorice treatment. And anti-tumor activity of licorice was evaluated in the C57BL/6 mice.

Results

We reported the G0/G1 growth phase cycle arrest of tumor cells induced by licorice is related to the down-regulation of CDK4-Cyclin D1 complex, which subsequently led to an increased protein abundance of PD-L1. Further, in vivo studies demonstrated that mitigating the outgrowth of NSCLC tumor induced by licorice was reliant on increased antigen presentation and improved CD8⁺ T cell infiltration.

Conclusions

Briefly, our findings improved the understanding of the anti-tumor effects of licorice with the systems pharmacology strategy, thereby promoting the development of natural products in prevention or treatment of cancers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02223-0.

The Crosstalk Between Tumor Cells and the Immune Microenvironment in Breast Cancer: Implications for Immunotherapy

Breast cancer progression is a complex process controlled by genetic and epigenetic factors that coordinate the crosstalk between tumor cells and the components of tumor microenvironment (TME). Among those, the immune cells play a dual role during cancer onset and progression, as they can protect from tumor progression by killing immunogenic neoplastic cells, but in the meanwhile can also shape tumor immunogenicity, contributing to tumor escape. The complex interplay between cancer and the immune TME influences the outcome of immunotherapy and of many other anti-cancer therapies. Herein, we present an updated view of the pro- and anti-tumor activities of the main immune cell populations present in breast TME, such as T and NK cells, myeloid cells, innate lymphoid cells, mast cells and eosinophils, and of the underlying cytokine-, cell–cell contact- and microvesicle-based mechanisms. Moreover, current and novel therapeutic options that can revert the immunosuppressive activity of breast TME will be discussed. To this end, clinical trials assessing the efficacy of CAR-T and CAR-NK cells, cancer vaccination, immunogenic cell death-inducing chemotherapy, DNA methyl transferase and histone deacetylase inhibitors, cytokines or their inhibitors and other immunotherapies in breast cancer patients will be reviewed. The knowledge of the complex interplay that elapses between tumor and immune cells, and of the experimental therapies targeting it, would help to develop new combination treatments able to overcome tumor immune evasion mechanisms and optimize clinical benefit of current immunotherapies.

Hematopoietic versus Solid Cancers and T Cell Dysfunction: Looking for Similarities and Distinctions

Simple Summary

Dysfunction of the immune T cell compartment occurs in many hematopoietic as well as solid cancers and hampers successful application of new immunotherapeutic approaches. A complete understanding of T cell dysfunction might improve the outcome of such therapies, but an overview in the various cancers is still lacking. We aim to map areas of similarities and differences in solid versus hematopoietic malignancies, providing a high-level rather than a detailed perspective on T cell dysfunction in those tumors.

Abstract

Cancer cells escape, suppress and exploit the host immune system to sustain themselves, and the tumor microenvironment (TME) actively dampens T cell function by various mechanisms. Over the last years, new immunotherapeutic approaches, such as adoptive chimeric antigen receptor (CAR) T cell therapy and immune checkpoint inhibitors, have been successfully applied for refractory malignancies that could only be treated in a palliative manner previously. Engaging the anti-tumor activity of the immune system, including CAR T cell therapy to target the CD19 B cell antigen, proved to be effective in acute lymphocytic leukemia. In low-grade hematopoietic B cell malignancies, such as chronic lymphocytic leukemia, clinical outcomes have been tempered by cancer-induced T cell dysfunction characterized in part by a state of metabolic lethargy. In multiple myeloma, novel antigens such as BCMA and CD38 are being explored for CAR T cells. In solid cancers, T cell-based immunotherapies have been applied successfully to melanoma and lung cancers, whereas application in e.g., breast cancer lags behind and is modestly effective as yet. The main hurdles for CAR T cell immunotherapy in solid tumors are the lack of suitable antigens, anatomical inaccessibility, and T cell anergy due to immunosuppressive TME. Given the wide range of success and failure of immunotherapies in various cancer types, it is crucial to comprehend the underlying similarities and distinctions in T cell dysfunction. Hence, this review aims at comparing selected, distinct B cell-derived versus solid cancer types and at describing means by which malignant cells and TME might dampen T cell anti-tumor activity, with special focus on immunometabolism. Drawing a meaningful parallel between the efficacy of immunotherapy and the extent of T cell dysfunction will shed light on areas where we can improve immune function to battle cancer.

A prognostic nomogram for lung adenocarcinoma based on immune-infiltrating Treg-related genes: from bench to bedside

Background

Accumulating evidence suggests that lymphocyte infiltration in the tumor microenvironment is positively correlated with tumorigenesis and development, while the role of Tregs (regulatory T cells) has been controversial. Therefore, we attempted to discover the possible value of Tregs for lung adenocarcinoma (LUAD).

Methods

The gene-sequencing data of LUAD were applied from three Gene Expression Omnibus (GEO) datasets—GSE10072, GSE32863 and GSE43458; the corresponding fractions of tumor-infiltrating immune cells were extracted from the CIBERSORTx portal. Weighted gene coexpression network analysis (WGCNA) and protein-protein interaction (PPI) network analysis were conducted to identify the significant module and candidate genes related to Tregs. The role of candidate genes in LUAD was further verified using data from The Cancer Genome Atlas (TCGA) database. Finally, we constructed a nomogram model to predict the prognosis of LUAD by plotting Kaplan-Meier (K-M), receiver operating characteristic (ROC) and calibration curves, which elucidated the performance of the nomogram.

Results

In total, 10,047 genes in 333 samples (196 tumor and 137 normal samples) from the GEO database were included. By WGCNA and PPI analysis, we identified a significant black module and 36 candidate genes related to Treg. Next, the candidate genes were verified using TCGA data by Cox regression analysis to screen 13 hub genes that stratified LUAD patients into low- or high-risk groups. Low-risk patients showed a significantly longer overall survival (OS) than high-risk patients (3-year OS: 70.2% vs. 35.2%; 5-year OS: 36.6% vs. 0; P=1.651E-09), and the areas under the ROC curves (AUCs) showed good (3-year AUC: 0.733; 5-year AUC: 0.777). Next, we constructed a survival nomogram combining the hub genes and clinical parameters; the low-risk patients still showed a favorable prognosis compared with that of the high-risk patients (P=7.073E-13), and the AUCs were better (3-year AUC: 0.763; 5-year AUC: 0.873).

Conclusions

We revealed the role of immune-infiltrating Treg-related genes in LUAD and constructed a prognostic nomogram, which may help clinicians make optimal therapeutic decisions and help patients obtain better outcomes.

Chimeric antigen receptor T-cell immunotherapy in breast cancer: development and challenges

Chimeric antigen receptor (CAR) T-cell therapy is an innovative form of immunotherapy wherein autologous T-cells are genetically modified to express chimeric receptors encoding an antigen-specific single-chain variable fragment and costimulatory molecules. Moreover, CAR T-cell therapy can only work successfully in patients who have an intact immune system. Therefore, patients receiving cytotoxic chemotherapy will be immunosuppressed making CAR-T therapy less effective. In adoptive CD8+ T-cell therapy (ACT), numerous tumor-specific, engineered T-cells are sourced from patients, expanded in vitro, and infused back expressing tumor-specific antigen receptors. The most successful ACT, anti-CD19 chimeric antigen receptor T-cell therapy directed against B-cell lymphoma, has proved to be efficacious. However, current efforts to utilize this approach for solid tumors, like breast cancer, have shown only modest improvement. Nevertheless, the potential efficacy of CAR-T therapy is promising in an era of immunological advances. By appropriately manipulating CAR T-cells to combat the immunosuppressive forces of the tumor microenvironment, significant eradication of the solid tumor may occur. This review discusses CAR T-cell therapy and its specificity and safety in adoptive cell transfers in breast cancer. We will highlight novel discoveries in CAR T-cell immunotherapy and the formidable barriers including suppression of T-cell function and localization at tumor sites.

Adoptive Cell Therapy in Breast Cancer: A Current Perspective of Next-Generation Medicine

Immunotherapy has become a cornerstone in the treatment of cancer and changed the way clinicians and researchers approach tumor vulnerabilities. Durable responses are commonly observed with immune checkpoint inhibitors in highly immunogenic tumors, while the infusion of T cells genetically engineered to express chimeric antigen receptors (CARs) has shown impressive efficacy in certain types of blood cancer. Nevertheless, harnessing our own immunity has not proved successful for most breast cancer patients. In the era of genomic medicine, cellular immunotherapies may provide a more personalized and dynamic tool against tumors displaying heterogeneous mutational landscapes and antigenic pools. This approach encompasses multiple strategies including the adoptive transfer of tumor-infiltrating lymphocytes, dendritic cells, natural killer cells, and engineered immune components such as CAR constructs and engineered T cell receptors. Although far from permeating the clinical setting, technical advances have been overwhelming in recent years, with continuous improvement in traditional challenges such as toxicity, adoptive cell persistence, and intratumoral trafficking. Also, there is an avid search for neoantigens that can be targeted by these strategies, either alone or in combination. In this work, we aim to provide a clinically-oriented overview of preclinical and clinical data regarding the use of cellular immunotherapies in breast cancer.