Macrophage-Based Approaches for Cancer Immunotherapy

Occurrences and Functions of Ly6Chi and Ly6Clo Macrophages in Health and Disease

Macrophages originating from the yolk sac or bone marrow play essential roles in tissue homeostasis and disease. Bone marrow-derived monocytes differentiate into Ly6C^hi and Ly6C^lo macrophages according to the differential expression of the surface marker protein Ly6C. Ly6C^hi and Ly6C^lo cells possess diverse functions and transcriptional profiles and can accelerate the disease process or support tissue repair and reconstruction. In this review, we discuss the basic biology of Ly6C^hi and Ly6C^lo macrophages, including their origin, differentiation, and phenotypic switching, and the diverse functions of Ly6C^hi and Ly6C^lo macrophages in homeostasis and disease, including in injury, chronic inflammation, wound repair, autoimmune disease, and cancer. Furthermore, we clarify the differences between Ly6C^hi and Ly6C^lo macrophages and their connections with traditional M1 and M2 macrophages. We also summarize the limitations and perspectives for Ly6C^hi and Ly6C^lo macrophages. Overall, continued efforts to understand these cells may provide therapeutic approaches for disease treatment.

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.

The Expression and Survival Significance of FOXD1 in Lung Squamous Cell Carcinoma: A Meta-Analysis, Immunohistochemistry Validation, and Bioinformatics Analysis

Accumulating evidence demonstrated that FOXD1 dysregulation was correlated with a broad spectrum of malignancies. However, litter is known about the role of FOXD1 in the progression of lung squamous cell carcinoma (LUSC). We conducted the comprehensive bioinformatics analysis to investigate FOXD1 expression in LUSC from TCGA and GEO datasets, and validated the FOXD1 expression pattern in clinical samples using immunohistochemistry method. ESTIMATE and CIBERSORT algorithms were performed to assess the relationship of FOXD1 and tumor microenvironment and immune cell infiltration. Our study showed that FOXD1 expression was significantly upregulated in LUSC tissues in TCGA dataset, validated by GEO datasets and clinical samples. In TCGA dataset, Kaplan-Meier curves showed that high FOXD1 expression was significantly correlated with favorable prognosis in LUSC patients. Moreover, FOXD1 expression has an impact on immune score and the proportions of immune cell infiltration subgroups. Finally, we predicted FOXD1 may be involved in many immune-related biological functions and cancer-related signaling pathways. Taken together, FOXD1 was upregulated in LUSC tissues, and FOXD1 expression could be a potential prognostic marker. FOXD1 might be associated with tumor microenvironment and perhaps a potential target in the tumor immunotherapy.

Off-the-Shelf Chimeric Antigen Receptor Immune Cells from Human Pluripotent Stem Cells

Autologous chimeric antigen receptor (CAR) T cells have expanded the scope and therapeutic potential of anti-cancer therapy. Nevertheless, autologous CAR-T therapy has been challenging due to labor some manufacturing processes for every patient, and the cost due to the complexity of the process. Moreover, T cell dysfunction results from the immunosuppressive tumor microenvironment in certain patients. Considering technical challenges in autologous donors, the development of safe and efficient allogeneic CAR-T therapy will address these issues. Since the advent of the generation of immune cells from pluripotent stem cells (PSCs), numerous studies focus on the off-the-shelf generation of CAR-immune cells derived from the universal donor PSCs, which simplifies the manufacturing process and standardizes CAR-T products. In this review, we will discuss advances in the generation of immune cells from PSCs, together with the potential and perspectives of CAR-T, CAR-macrophages, and CAR-natural killer (NK) cells in cancer treatment. The combination of PSC-derived immune cells and CAR engineering will pave the way for developing next-generation cancer immunotherapy.

Integrative analysis identifies CXCL11 as an immune-related prognostic biomarker correlated with cell proliferation and immune infiltration in multiple myeloma microenvironment

Purpose

The interaction between tumor cells and tumor microenvironment (TME) has an important impact on progression and prognosis of multiple myeloma (MM), and has been proven to be promising therapeutic targets. This study intended to explore the relationship between TME and prognosis and identify valuable biomarkers of MM.

Methods

The transcriptomic and clinical information of MM retrieved from the Gene Expression Omnibus (GEO) were used to establish the model. The curve of Kaplan–Meier survival and the time-dependent receiver operating characteristic (ROC) were used to appraise the predictive ability. A nomogram was established for clinical application. Furthermore, the CIBERSORT algorithm was used to investigate the relation between IRGPI with the infiltration of immune cells. We also used histology, as well as in vitro and in vivo experiments to validate these findings.

Results

The results demonstrated an immune-related gene-based prognostic index (IRGPI) combined with clinical information. Patients were separated into high- and low-risk groups based on risk score, which had significantly difference in survival status and immune infiltrations. Furthermore, we identified CXCL11 as a key factor, which positively promotes the progression of MM and correlate with macrophage M2-like polarization and tumor immune cells infiltration.

Conclusion

Our findings suggest the IRGPI significantly demonstrate the differential prognosis and prediction of immune cells infiltration. It provides some insights into the complex interaction between myeloma tumor cells and the TME, as well as in the development of a novel biomarker target for anti-MM therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02608-9.

Application of lipid nanovesicle drug delivery system in cancer immunotherapy

Immunotherapy has gradually emerged as the most promising anticancer therapy. In addition to conventional anti-PD-1/PD-L1 therapy, anti-CTLA-4 therapy, CAR-T therapy, etc., immunotherapy can also be induced by stimulating the maturation of immune cells or inhibiting negative immune cells, regulating the tumor immune microenvironment and cancer vaccines. Lipid nanovesicle drug delivery system includes liposomes, cell membrane vesicles, bacterial outer membrane vesicles, extracellular vesicles and hybrid vesicles. Lipid nanovesicles can be used as functional vesicles for cancer immunotherapy, and can also be used as drug carriers to deliver immunotherapy drugs to the tumor site for cancer immunotherapy. Here, we review recent advances in five kinds of lipid nanovesicles in cancer immunotherapy and assess the clinical application prospects of various lipid nanovesicles, hoping to provide valuable information for clinical translation in the future.

Homogeneous Polyporus Polysaccharide Inhibit Bladder Cancer by Resetting Tumor-Associated Macrophages Toward M1 Through NF-κB/NLRP3 Signaling

Bladder cancer(BC)is one of the most common urinary system tumors, which characterized by a high incidence. Polyporus polysaccharide is the main active component of polyporus, which is clinically used in the treatment of bladder cancer, but the mechanism is not clear. In previous study, we isolated homogeneous polyporus polysaccharide(HPP) with high purity from polyporus. The goal of this study was to assess the polarization of macrophages induced by HPP in the bladder tumor microenvironment and explored its anti-bladder cancer mechanism through BBN bladder cancer rat model and Tumor associated macrophages(TAM). The results suggested that HPP regulates TAM polarization to improve the tumor inflammatory microenvironment, possibly through the NF-κB/NLRP3 signaling pathway. Our results suggested that HPP may be a potential therapeutic agent for bladder tumors.

Adoptive Cell Therapy in Pediatric and Young Adult Solid Tumors: Current Status and Future Directions

Advances from novel adoptive cellular therapies have yet to be fully realized for the treatment of children and young adults with solid tumors. This review discusses the strategies and preliminary results, including T-cell, NK-cell and myeloid cell-based therapies. While each of these approaches have shown some early promise, there remain challenges. These include poor trafficking to the tumor as well as a hostile tumor microenvironment with numerous immunosuppressive mechanisms which result in exhaustion of cellular therapies. We then turn our attention to new strategies proposed to address these challenges including novel clinical trials that are ongoing and in development.

Human Tumor Targeted Cytotoxic Mast Cells for Cancer Immunotherapy

The diversity of autologous cells being used and investigated for cancer therapy continues to increase. Mast cells (MCs) are tissue cells that contain a unique set of anti-cancer mediators and are found in and around tumors. We sought to exploit the anti-tumor mediators in MC granules to selectively target them to tumor cells using tumor specific immunoglobin E (IgE) and controllably trigger release of anti-tumor mediators upon tumor cell engagement. We used a human HER2/neu-specific IgE to arm human MCs through the high affinity IgE receptor (FcεRI). The ability of MCs to bind to and induce apoptosis of HER2/neu-positive cancer cells in vitro and in vivo was assessed. The interactions between MCs and cancer cells were investigated in real time using confocal microscopy. The mechanism of action using cytotoxic MCs was examined using gene array profiling. Genetically manipulating autologous MC to assess the effects of MC-specific mediators have on apoptosis of tumor cells was developed using siRNA. We found that HER2/neu tumor-specific IgE-sensitized MCs bound, penetrated, and killed HER2/neu-positive tumor masses in vitro. Tunneling nanotubes formed between MCs and tumor cells are described that parallel tumor cell apoptosis. In solid tumor, human breast cancer (BC) xenograft mouse models, infusion of HER2/neu IgE-sensitized human MCs co-localized to BC cells, decreased tumor burden, and prolonged overall survival without indications of toxicity. Gene microarray of tumor cells suggests a dependence on TNF and TGFβ signaling pathways leading to apoptosis. Knocking down MC-released tryptase did not affect apoptosis of cancer cells. These studies suggest MCs can be polarized from Type I hypersensitivity-mediating cells to cytotoxic cells that selectively target tumor cells and specifically triggered to release anti-tumor mediators. A strategy to investigate which MC mediators are responsible for the observed tumor killing is described so that rational decisions can be made in the future when selecting which mediators to target for deletion or those that could further polarize them to cytotoxic MC by adding other known anti-tumor agents. Using autologous human MC may provide further options for cancer therapeutics that offers a unique anti-cancer mechanism of action using tumor targeted IgE’s.

Single-Cell Transcriptome Analysis Reveals Inter-Tumor Heterogeneity in Bilateral Papillary Thyroid Carcinoma

BACKGROUND

The tumor microenvironment (TME) plays a pivotal role in cancer progression in papillary thyroid carcinoma (PTC), yet the composition and the phenotype of cells within the TME in bilateral PTC are poorly understood.

METHODS

We performed unbiased transcriptome-wide single-cell RNA sequencing (scRNA-seq) analysis on 29,561 cells from 3 pairs of bilateral PTC and 1 non-tumor thyroid sample. The results of the analysis were validated by a large-scale bulk transcriptomic dataset deposited in The Cancer Genome Atlas (TCGA) database.

RESULTS

Our integrative analysis of thyroid follicular cells revealed 42 signaling pathways enriched in malignant follicular cells, including cytokine-cytokine receptor interaction, PI3K/Akt signaling pathway, mitogen-activated protein kinase (MAPK) signaling pathway, and tumor necrosis factor (TNF) signaling pathway. A 6-gene signature (CXCL3, CXCL1, IL1A, CCL5, TNFRSF12A, and IL18) in the cytokine-cytokine receptor interaction pathway was constructed to predict the prognosis of patients with PTC, with high risk scores being associated with decreased overall survival [hazard ratio (HR) = 3.863, 95% CI = 2.233-6.682, p < 0.001]. Gene set variation analysis (GSVA) indicated that the pathways enriched in bilateral PTC were significantly different, indicating great heterogeneity in bilateral PTC, even with the same BRAF V600E mutation. Comprehensive analysis of T cells revealed that the proportion of CD8+ tissue-resident memory T cells expressing IFNG decreased in tumor samples with advanced N stage. Within the myeloid compartment, the ratio of suppressive M2-like to pro-inflammatory M1-like macrophages increased with advanced disease stage, which was confirmed in the bulk dataset using transcriptomic profiles. In addition, we also identified numerous biologically critical interactions among myeloid cells, T cells, and follicular cells, which were related to T-cell recruitment, M2-like macrophage polarization, malignant follicular cell progression, and T-cell inhibitory signaling.

CONCLUSION

Our integrative analyses revealed great inter-tumor heterogeneity within the TME in bilateral PTC, which will offer assistance for precise diagnosis and treatment.

A SIRPαFc Fusion Protein Conjugated With the Collagen-Binding Domain for Targeted Immunotherapy of Non-Small Cell Lung Cancer

The SIRPαFc fusion protein can block the immunosuppressive CD47-SIRPα signal between macrophages and tumor cells as a decoy receptor and has demonstrated its immunotherapeutic efficacy in various tumors. However, its clinical application was limited because of the potential hematologic toxicity. The heptapeptide “TKKTLRT” is a collagen-binding domain (CBD) which can bind collagen specifically. Herein, we aim to improve the tumor targeting of SIRPαFc and therefore avoid its unnecessary exposure to normal cells through synthesizing a TKKTLRT–SIRPαFc conjugate. Experiments at molecular and cellular levels indicate that the TKKTLRT–SIRPαFc conjugate-derived collagen-binding affinity and the introduction of CBD did not impact the CD47-binding affinity as well as its phagocytosis-promoting effect on NSCLC cells. In vivo distribution experiments showed that CBD–SIRPαFc accumulated in tumor tissue more effectively compared to unmodified SIRPαFc, probably due to the exposed collagen in the tumor vascular endothelium and stroma resulting from the abnormal vessel structure. On an A549 NSCLC nude mouse xenograft model, CBD–SIRPαFc presented more stable and effective antitumor efficacy than SIRPαFc, along with significantly increased CD11b⁺F4/80⁺ macrophages especially MHC II⁺ M1 macrophages within tumors. All of these results revealed that CBD brought a tumor-targeting ability to the SIRPαFc fusion protein, which contributed to the enhanced antitumor immune response. Altogether, the CBD–SIRPαFc conjugate may have the potential to be an effective tumor immunotherapy with improved antitumor efficacy but less non-tumor-targeted side effect.

FGF-2 signaling in nasopharyngeal carcinoma modulates pericyte-macrophage crosstalk and metastasis

Molecular signaling in the tumor microenvironment (TME) is complex, and crosstalks among various cell compartments in supporting metastasis remain poorly understood. In particular, the role of vascular pericytes, a critical cellular component in the TME, in cancer invasion and metastasis warrants further investigation. Here we report an elevation of FGF-2 signaling in both nasopharyngeal carcinoma (NPC) patient samples and xenograft mouse models promotes NPC metastasis. Mechanistically, tumor cell-derived FGF-2 strongly promoted pericyte proliferation and pericyte-specific expression of an orphan chemokine (C-X-C motif) ligand 14 (CXCL14) via FGFR1- AHR signaling. Gain and loss-of-function experiments validated that pericyte-derived CXCL14 promoted macrophage recruitment and polarization towards an M2-like phenotype. Genetic knockdown of FGF2 or genetic depletion of tumoral pericytes blocked CXCL14 expression and tumor-associated macrophage (TAM) infiltration. Pharmacological inhibition of TAMs by clodronate liposomes treatment resulted in a reduction of FGF-2-induced pulmonary metastasis. Together, these findings shed light on the inflammatory role of tumoral pericytes in promoting TAM-mediated metastasis. We provide mechanistic insight into an FGF-2-FGFR1-pericyte-CXCL14-TAM stromal communication axis in NPC and propose an effective anti-metastasis therapy concept by targeting a pericyte-derived inflammation for NPC or FGF-2-high tumors.

Tumor Immunogenomic Features Determine Outcomes in Patients with Metastatic Colorectal Cancer Treated with Standard-of-Care Combinations of Bevacizumab and Cetuximab

PURPOSE

CALGB/SWOG 80405 was a randomized phase III trial in first-line patients with metastatic colorectal cancer treated with bevacizumab, cetuximab, or both, plus chemotherapy. We tested the effect of tumor immune features on overall survival (OS).

EXPERIMENTAL DESIGN

Primary tumors (N = 554) were profiled by RNA sequencing. Immune signatures of macrophages, lymphocytes, TGFβ, IFNγ, wound healing, and cytotoxicity were measured. CIBERSORTx scores of naive and memory B cells, plasma cells, CD8+ T cells, resting and activated memory CD4+ T cells, M0 and M2 macrophages, and activated mast cells were measured.

RESULTS

Increased M2 macrophage score [HR, 6.30; 95% confidence interval (CI), 3.0-12.15] and TGFβ signature expression (HR, 1.35; 95% CI, 1.05-1.77) were associated with shorter OS. Increased scores of plasma cells (HR, 0.55; 95% CI, 0.38-0.87) and activated memory CD4+ T cells (HR, 0.34; 95% CI, 0.16-0.65) were associated with longer OS. Using optimal cutoffs from these four features, patients were categorized as having either 4, 3, 2, or 0-1 beneficial features associated with longer OS, and the median (95% CI) OS decreased from 42.5 (35.8-47.8) to 31.0 (28.8-34.4), 25.2 (20.6-27.9), and 17.7 (13.5-20.4) months respectively (P = 3.48e-11).

CONCLUSIONS

New immune features can be further evaluated to improve patient response. They provide the rationale for more effective immunotherapy strategies.

Identification and Validation of a Prognostic Immune-Related Gene Signature in Esophageal Squamous Cell Carcinoma

Esophageal carcinoma (EC) is a common malignant cancer worldwide. Esophageal squamous cell carcinoma (ESCC), the main type of EC, is difficult to treat because of the widespread morbidity, high fatality rates, and low quality of life caused by postoperative complications and no specific molecular target. In this study, we screened genes to establish a prognostic model for ESCC. The transcriptome expression profiles of 81 ESCC tissues and 340 normal esophageal mucosal epithelium tissues were obtained from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) cohorts. The transcriptome expression datasets of 19 esophageal squamous carcinoma cell lines were downloaded from Cancer Cell Line Encyclopedia (CCLE). The R software Limma package was used to identify 6,231 differentially expressed genes and 647 differentially expressed immune-related genes between normal and ESCC tissues. Gene functional analysis was performed using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). Weighted gene co-expression network analysis (WGCNA) was used to screen out 18 immune-related prognostic genes. We then established the prognostic and risk signature using these genes, and the patients were divided into low-risk and high-risk groups. Compared with high-risk group patients, the low-risk group patients had longer overall survival. M1 macrophages and resting dendritic cells were differentially distributed between the low-risk and high-risk groups and were related to patient survival. We also examined the functional immune cell and immune molecule levels in low-risk and high-risk group patients, with significant differences in the tumor microenvironment between the two groups. To further verify the accuracy of the prognostic risk model, we performed area under the ROC curve (AUC) analysis. The AUC value was 0.931 for the prognostic risk, which was better than the microsatellite instability (MSI) and Tumor Immune Dysfunction and Exclusion (TIDE) scores. In conclusion, we found 18 immune-related prognostic genes related to the occurrence of ESCC and established a prognostic model for predicting disease severity.

Harnessing the Anti-Tumor Mediators in Mast Cells as a New Strategy for Adoptive Cell Transfer for Cancer

The emergence of cancer immunotherapies utilizing adoptive cell transfer (ACT) continues to be one of the most promising strategies for cancer treatment. Mast cells (MCs) which occur throughout vascularized tissues, are most commonly associated with Type I hypersensitivity, bind immunoglobin E (IgE) with high affinity, produce anti-cancer mediators such as tumor necrosis factor alpha (TNF-α) and granulocyte macrophage colony-stimulating factor (GM-CSF), and generally populate the tumor microenvironments. Yet, the role of MCs in cancer pathologies remains controversial with evidence for both anti-tumor and pro-tumor effects. Here, we review the studies examining the role of MCs in multiple forms of cancer, provide an alternative, MC-based hypothesis underlying the mechanism of therapeutic tumor IgE efficacy in clinical trials, and propose a novel strategy for using tumor-targeted, IgE-sensitized MCs as a platform for developing new cellular cancer immunotherapies. This autologous MC cancer immunotherapy could have several advantages over current cell-based cancer immunotherapies and provide new mechanistic strategies for cancer therapeutics alone or in combination with current approaches.

Optimizing the Method for Differentiation of Macrophages from Human Induced Pluripotent Stem Cells

Macrophage is a very promising cell type for cancer immunotherapy, yet it is difficult to obtain enough functional macrophages for clinical cell therapy. Herein, we descibe a reliable method to produce functional macrophages through the differentiation of human induced pluripotent stem cells (hiPSCs). By optimizing the size control of embryoid bodies (EBs), we accelerated the differentiation process of macrophages and increased the production of macrophages without attenuating macrophage functions. Our final yield of macrophages was close to 50-fold of starting iPSCs. The macrophages showed phagocytic capacity in vitro and a xenograft tumor model. M0 macrophages could be further polarized into M1 and M2 subtypes, and M1 cells exhibited typical proinflammatory characteristics. Moreover, we found that hematopoietic differentiation originated from the outside of EB and matured inward gradually. Taken together, our protocol provides an effective method for the generation of macrophages comparable to blood-derived macrophages, which provides potential value for cell therapy and gene editing studies.

Driving role of macrophages in transition from acute kidney injury to chronic kidney disease

Acute kidney injury (AKI), characterized by acute renal dysfunction, is an increasingly common clinical problem and an important risk factor in the subsequent development of chronic kidney disease (CKD). Regardless of the initial insults, the progression of CKD after AKI involves multiple types of cells, including renal resident cells and immune cells such as macrophages. Recently, the involvements of macrophages in AKI-to-CKD transition have garnered significant attention. Furthermore, substantial progress has also been made in elucidating the pathophysiological functions of macrophages from the acute kidney to repair or fibrosis. In this review, we highlight current knowledge regarding the roles and mechanisms of macrophage activation and phenotypic polarization, and transdifferentiation in the development of AKI-to-CKD transition. In addition, the potential of macrophage-based therapy for preventing AKI-to-CKD transition is also discussed.

IgD ligation allows peritoneal cavity B cell proliferation

Atypical cytokine production and immune cell subset ratios, particularly those that include high proportions of macrophages, characterize tumor microenvironments (TMEs). TMEs can be modeled by culturing peritoneal cavity (PerC) cells which have a high macrophage to lymphocyte ratio. With TCR or BCR ligation, PerC lymphocyte proliferation is tempered by macrophages. However, PHA (T cells) and anti-CD40 (B cells) are activators that induce proliferation. Herein, we report that ligating IgD, in contrast to IgM, triggers PerC B cell proliferation. IL-4 addition enhanced the IgD response for BALB/c PerC B cells but suppressed that of C57BL/6 mice. Intriguingly, concurrent ligation of IgD and CD3_ε rescued a PerC T cell proliferative response. These results serve to expand the list of targets for promoting cellular and humoral immunity in conditions that model macrophage-rich TMEs.

Recent advances in targeted drug delivery for the treatment of pancreatic ductal adenocarcinoma

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) has become a serious health problem with high impact worldwide. The heterogeneity of PDAC makes it difficult to apply drug delivery systems (DDS) used in other cancer models, for example, the poorly developed vascular system makes anti-angiogenic therapy ineffective. Due to its various malignant pathological changes, drug delivery against PDAC is a matter of urgent concern. Based on this situation, various drug delivery strategies specially designed for PDAC have been generated.

AREAS COVERED

This review will briefly describe how delivery systems can be designed through nanotechnology and formulation science. Most research focused on penetrating the stromal barrier, exploiting and alleviating the hypoxic microenvironment, targeting immune cells, or designing vaccines, and combination therapies. This review will summarize the ways to reverse the malignant pathological features of PDAC and hopefully provide ideas for subsequent studies.

EXPERT OPINION

Drug delivery systems designed to achieve penetrating functions or to alleviate hypoxia and activate immunity have achieved good therapeutic results in animal models in several studies. In future studies, there is a need to deliver PDAC therapeutics in a more precise manner, or the use of drug carriers for multiple functions simultaneously, are potential therapeutic strategy.

Challenges and Opportunities for Immunotherapeutic Intervention against Myeloid Immunosuppression in Glioblastoma

Glioblastoma multiforme (GBM), the most common and deadly brain cancer, exemplifies the paradigm that cancers grow with help from an immunosuppressive tumor microenvironment (TME). In general, TME includes a large contribution from various myeloid lineage-derived cell types, including (in the brain) altered pathogenic microglia as well as monocyte-macrophages (Macs), myeloid-derived suppressor cells (MDSC) and dendritic cell (DC) populations. Each can have protective roles, but has, by definition, been coopted by the tumor in patients with progressive disease. However, evidence demonstrates that myeloid immunosuppressive activities can be reversed in different ways, leading to enthusiasm for this therapeutic approach, both alone and in combination with potentially synergistic immunotherapeutic and other strategies. Here, we review the current understanding of myeloid cell immunosuppression of anti-tumor responses as well as potential targets, challenges, and developing means to reverse immunosuppression with various therapeutics and their status. Targets include myeloid cell colony stimulating factors (CSFs), insulin-like growth factor 1 (IGF1), several cytokines and chemokines, as well as CD40 activation and COX2 inhibition. Approaches in clinical development include antibodies, antisense RNA-based drugs, cell-based combinations, polarizing cytokines, and utilizing Macs as a platform for Chimeric Antigen Receptors (CAR)-based tumor targeting, like with CAR-T cells. To date, promising clinical results have been reported with several of these approaches.

Apoptosis Induction, a Sharp Edge of Berberine to Exert Anti-Cancer Effects, Focus on Breast, Lung, and Liver Cancer

Cancer is the leading cause of death and one of the greatest barriers to increased life expectancy worldwide. Currently, chemotherapy with synthetic drugs remains one of the predominant ways for cancer treatment, which may lead to drug resistance and normal organ damage. Increasing researches have suggested that apoptosis, a type of programmed cell death, is a promising way for cancer therapy. Furthermore, natural products are important sources for finding new drugs with high availability, low cost and low toxicity. As a well-known isoquinoline alkaloid, accumulating evidence has revealed that berberine (BBR) exerts potential pro-apoptotic effects on multiple cancers, including breast, lung, liver, gastric, colorectal, pancreatic, and ovarian cancers. The related potential signal pathways are AMP-activated protein kinase, mitogen-activated protein kinase, and protein kinase B pathways. In this review, we provide a timely and comprehensive summary of the detailed molecular mechanisms of BBR in treating three types of cancer (breast, lung and liver cancer) by inducing apoptosis. Furthermore, we also discuss the existing challenges and strategies to improve BBR’s bioavailability. Hopefully, this review provides valuable information for the comprehension of BBR in treating three types of cancer and highlight the pro-apoptotic effects of BBR, which would be beneficial for the further development of this natural compound as an effective clinical drug for treating cancers.

Nanotherapeutic macrophage-based immunotherapy for the peritoneal carcinomatosis of lung cancer

Lung cancer is the top cause of cancer mortality in the world. Distant metastasis leads to high mortality. Abdominal metastasis of lung cancer is characterized by very poor prognosis and the median survival time is usually less than two months. Therefore, it is of clinical significance to develop a new effective method for the treatment of abdominal metastasis of lung cancer. Cell therapy has promoted the development of new technology and strategy in oncology. Macrophages, as an important component of solid tumors, have also attracted great attention as a promising strategy of cell therapy in oncology. However, the reinfusion of autologous macrophages would be easily "re-educated" by the tumor microenvironment into a phenotype that promotes tumor development. This work developed a potential therapy using celastrol nanoparticle-containing M1-like macrophages (NP@M1) as a combinatory therapeutic system. M1-like macrophages (M1Φ) not only can serve as a drug delivery carrier for celastrol but also as a biotherapeutic agent. In turn, the celastrol nanoparticles (NPs) can maintain an anticancer polarized status of M1Φ, and subsequently, the exocytosed NPs can also execute the tumor cell-killing effect. Such a system thus provides a "two-birds-one-stone" therapeutic strategy and a proof of concept for the currently incurable abdominal metastasis of lung cancer.

Advances in CAR-T Cell Genetic Engineering Strategies to Overcome Hurdles in Solid Tumors Treatment

During this last decade, adoptive transfer of T lymphocytes genetically modified to express chimeric antigen receptors (CARs) emerged as a valuable therapeutic strategy in hematological cancers. However, this immunotherapy has demonstrated limited efficacy in solid tumors. The main obstacle encountered by CAR-T cells in solid malignancies is the immunosuppressive tumor microenvironment (TME). The TME impedes tumor trafficking and penetration of T lymphocytes and installs an immunosuppressive milieu by producing suppressive soluble factors and by overexpressing negative immune checkpoints. In order to overcome these hurdles, new CAR-T cells engineering strategies were designed, to potentiate tumor recognition and infiltration and anti-cancer activity in the hostile TME. In this review, we provide an overview of the major mechanisms used by tumor cells to evade immune defenses and we critically expose the most optimistic engineering strategies to make CAR-T cell therapy a solid option for solid tumors.

Metabolic installation of macrophage-recruiting glycan ligand on tumor cell surface for in vivo tumor suppression

Synthetic probes that could direct immune cells against tumors are potential immunotherapeutics. We herein report in vivo tumor suppression via an intravenously injected abiotic sialic acid (TCCSia) that could be metabolically incorporated into tumor cell surface to yield of a high affinity ligand (TCCSiaα2,3-Gal) of Siglec-1 specifically expressed on macrophages. We observed marked suppression of pulmonary metastasis and subcutaneous tumor growth of B16F10 melanoma cells in mice with TCCSia, suggesting the utility of abiotic sialic acid to modulate tumor immunity via recruiting Siglec+ immune cells.

Cell-based immunotherapies in gynecologic cancers

PURPOSE OF REVIEW

This review provides an update on recent developments in cell-based immunotherapy in gynecologic cancers.

RECENT FINDINGS

Chimeric antigen receptor (CAR) technology has made significant progress allowing now for not only expressing CARs on T-cells, but also on other immune effector cells, such as natural killer cells and macrophages. Cell-based vaccines have started to show promising results in clinical trials.

SUMMARY

Cell-based immunotherapies in gynecologic cancers continue to evolve with promising clinical efficacy in select patients.

BiTE secretion from in situ-programmed myeloid cells results in tumor-retained pharmacology

Bispecific T-Cell Engagers (BiTEs) are effective at inducing remission in hematologic cancers, but their use in solid tumors has been challenging due to their extreme potency and on-target, off-tumor toxicities in healthy tissue. Their deployment against solid tumors is further complicated by insufficient drug penetration, a hostile tumor microenvironment, and immune escape. To address these challenges, we developed targeted nanocarriers that can deliver in vitro-transcribed mRNA encoding BiTEs to host myeloid cells – a cell type that is actively recruited into the tumor microenvironment. We demonstrate in an immunocompetent mouse model of ovarian cancer, that infusion of these nanoparticles directs BiTE expression to tumor sites, which reshapes the microenvironment from suppressive to permissive and triggers disease regression without systemic toxicity. In contrast, conventional injections of recombinant BiTE protein at doses required to achieve anti-tumor activity, induced systemic inflammatory responses and severe tissue damage in all treated animals. Implemented in the clinic, this in situ gene therapy could enable physicians – with a single therapeutic – to safely target tumor antigen that would otherwise not be druggable due to the risks of on-target toxicity and, at the same time, reset the tumor milieu to boost key mediators of antitumor immune responses.

Fighting fire with fire: the immune system might be key in our fight against Alzheimer's disease

The ultimate cause of Alzheimer's disease (AD) is still unknown and no disease-modifying treatment exists. Emerging evidence supports the concept that the immune system has a key role in AD pathogenesis. This awareness leads to the idea that specific parts of the immune system must be engaged to ward off the disease. Immunotherapy has dramatically improved the management of several previously untreatable cancers and could hold similar promise as a novel therapy for treating AD. However, before potent immunotherapies can be rationally designed as treatment against AD, we need to fully understand the dynamic interplay between AD and the different parts of our immune system. Accordingly, here we review the most important aspects of both the innate and adaptive immune system in relation to AD pathology. Teaser: Emerging results support the concept that Alzheimer's disease is affected by the inability of the immune system to contain the pathology of the brain. Here, we discuss how we can engage our immune system to fight this devastating disease.

Pan-Cancer Integrated Analysis of HSF2 Expression, Prognostic Value and Potential Implications for Cancer Immunity

Heat shock factor 2 (HSF2), a transcription factor, plays significant roles in corticogenesis and spermatogenesis by regulating various target genes and signaling pathways. However, its expression, clinical significance and correlation with tumor-infiltrating immune cells across cancers have rarely been explored. In the present study, we comprehensively investigated the expression dysregulation and prognostic significance of HSF2, and the relationship with clinicopathological parameters and immune infiltration across cancers. The mRNA expression status of HSF2 was analyzed by TCGA, GTEx, and CCLE. Kaplan-Meier analysis and Cox regression were applied to explore the prognostic significance of HSF2 in different cancers. The relationship between HSF2 expression and DNA methylation, immune infiltration of different immune cells, immune checkpoints, tumor mutation burden (TMB), and microsatellite instability (MSI) were analyzed using data directly from the TCGA database. HSF2 expression was dysregulated in the human pan-cancer dataset. High expression of HSF2 was associated with poor overall survival (OS) in BRCA, KIRP, LIHC, and MESO but correlated with favorable OS in LAML, KIRC, and PAAD. The results of Cox regression and nomogram analyses revealed that HSF2 was an independent factor for KIRP, ACC, and LIHC prognosis. GO, KEGG, and GSEA results indicated that HSF2 was involved in various oncogenesis- and immunity-related signaling pathways. HSF2 expression was associated with TMB in 9 cancer types and associated with MSI in 5 cancer types, while there was a correlation between HSF2 expression and DNA methylation in 27 types of cancer. Additionally, HSF2 expression was correlated with immune cell infiltration, immune checkpoint genes, and the tumor immune microenvironment in various cancers, indicating that HSF2 could be a potential therapeutic target for immunotherapy. Our findings revealed the important roles of HSF2 across different cancer types.

Myeloid Immune Cells CARrying a New Weapon Against Cancer

Chimeric antigen receptor (CAR) engineering for T cells and natural killer cells (NK) are now under clinical evaluation for the treatment of hematologic cancers. Although encouraging clinical results have been reported for hematologic diseases, pre-clinical studies in solid tumors have failed to prove the same effectiveness. Thus, there is a growing interest of the scientific community to find other immune cell candidate to express CAR for the treatment of solid tumors and other diseases. Mononuclear phagocytes may be the most adapted group of cells with potential to overcome the dense barrier imposed by solid tumors. In addition, intrinsic features of these cells, such as migration, phagocytic capability, release of soluble factors and adaptive immunity activation, could be further explored along with gene therapy approaches. Here, we discuss the elements that constitute the tumor microenvironment, the features and advantages of these cell subtypes and the latest studies using CAR-myeloid immune cells in solid tumor models.

HMGA2 facilitates colorectal cancer progression via STAT3-mediated tumor-associated macrophage recruitment

Rationale: Tumor-associated macrophages (TAMs), generally displaying the pro-tumor M2-like phenotype, strongly influence the progression of colorectal cancer (CRC) via their immunosuppressive activities. The high-mobility gene group A2 (HMGA2), an oncoprotein, is aberrantly overexpressed in CRC cells. However, the mechanisms by which tumor-derived HMGA2 modulates tumor microenvironment in CRC remain poorly understood.

Methods:In vivo subcutaneous tumor xenograft model, azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced tumor mouse model and in vitro co-culture assays were used to investigate the Hmga2 role in TAM recruitment and polarization. Luciferase and chromatin immunoprecipitation (ChIP) assays were applied to examine the mechanism of HMGA2-mediated transcriptional regulation of signal transducer and activator of transcription 3 (STAT3). The CD68 correlation with patient outcome was analyzed in 167 human CRC tissues.

Results: We found that HMGA2 in cancer cells promoted macrophage recruitment and M2 polarization in vitro and in vivo. HMGA2 directly bound to the STAT3 promoter to activate its transcription and subsequently induced CCL2 secretion, thus promoting macrophage recruitment. Our results from human CRC specimens also revealed a strong positive association between HMGA2 expression in tumor cells and CD68 expression in the stroma. We further showed that patients with an elevated CD68 expression had an unfavorable overall survival in all of the patients or in the subgroup with negative distant metastasis.

Conclusion: Our work uncovers new insight into the link between the HMGA2/STAT3/CCL2 axis and macrophage recruitment in CRC. These findings provide a novel therapeutic option for targeting the HMGA2/STAT3/CCL2 axis in CRC.

Recent progress of macrophage vesicle-based drug delivery systems

Nanoparticle drug delivery systems (NDDSs) are promising platforms for efficient delivery of drugs. In the past decades, many nanomedicines have received clinical approval and completed translation. With the rapid advance of nanobiotechnology, natural vectors are emerging as novel strategies to carry and delivery nanoparticles and drugs for biomedical applications. Among diverse types of cells, macrophage is of great interest for their essential roles in inflammatory and immune responses. Macrophage-derived vesicles (MVs), including exosomes, microvesicles, and those from reconstructed membranes, may inherit the chemotactic migration ability and high biocompatibility. The unique properties of MVs make them competing candidates as novel drug delivery systems for precision nanomedicine. In this review, the advantages and disadvantages of existing NDDSs and MV-based drug delivery systems (MVDDSs) were compared. Then, we summarized the potential applications of MVDDSs and discuss future perspectives. The development of MVDDS may provide avenues for the treatment of diseases involving an inflammatory process.

Role of macrophages in cancer progression and targeted immunotherapies

The vast complexity of the tumor microenvironment (TME) aggrandizes the underlying principles responsible for immune escape, therapy resistance, and treatment failure. The stromal and immune cell population circumjacent to the tumor cells affects the cancer cell cycle leading to tumor progression. Tumor-associated macrophages (TAMs) exhibiting a unique M2 polarization state constitute a significant portion of the TME. They serve as tumor suppressors at early stages and tumor promoters at advanced stages by governing various microenvironmental cues. TAMs secreted various pro-tumoral cytokines, chemokines, and matrix metalloproteases are known to regulate the different cell cycle molecules including checkpoint inhibitors in cancer cells leading to cell cycle progression with faulty cellular components. Moreover, TAMs are well-known immunosuppressors and thereby facilitating the tumor cells' evasion from immune recognition. This chapter will describe the interaction between TAMs and tumor cells, the involvement of TAMs in the regulation of cancer cell progression by controlling cell cycle checkpoints or molecular pathways, and current TAM-based therapies, including restriction of TAM recruitment, anti-survival strategies, or switching polarity. Moreover, this chapter will also emphasize recently developed drug targets and CAR-macrophage cell therapy that restricts tumor progression.

Glycogenes in Oncofetal Chondroitin Sulfate Biosynthesis are Differently Expressed and Correlated With Immune Response in Placenta and Colorectal Cancer

Oncofetal chondroitin sulfate expression plays an important role in the development of tumors and the pathogenesis of malaria in pregnancy. However, the biosynthesis and functions of these chondroitin sulfates, particularly the tissue-specific regulation either in tumors or placenta, have not been fully elucidated. Here, by examining the glycogenes availability in chondroitin sulfate biosynthesis such as xylosytransferase, chondroitin synthase, sulfotransferase, and epimerase, the conserved or differential CS glycosylation in normal, colorectal cancer (CRC), and placenta tissue were predicted. We found that the expression of seven chondroitin sulfate biosynthetic enzymes, namely B4GALT7, B3GALT6, B3GAT3, CHSY3, CHSY1, CHPF, and CHPF2, were significantly increased, while four other enzymes (XYLT1, CHST7, CHST15, and UST) were decreased in the colon adenocarcinoma (COAD) and rectum adenocarcinoma (READ) patients. In the human placenta, where the distinct chondroitin sulfate is specifically bound with VAR2CSA on Plasmodium parasite-infected RBC, eight chondroitin sulfate biosynthesis enzymes (CSGALNACT1, CSGALNACT2, CHSY3, CHSY1, CHPF, DSE, CHST11, and CHST3) were significantly higher than the normal colon tissue. The similarly up-regulated chondroitin synthases (CHSY1, CHSY3, and CHPF) in both cancer tissue and human placenta indicate an important role of the proteoglycan CS chains length for Plasmodium falciparum VAR2CSA protein binding. Interestingly, twelve highly expressed chondroitin sulfate enzymes were significantly correlated to worse outcomes (prognosis) in both COAD and READ. Furthermore, we showed that the levels of chondroitin sulfate enzymes are significantly correlated with the expression of immuno-regulators and immune infiltration levels in CRCs and placenta, and involved in multiple essential pathways, such as extracellular matrix organization, epithelial-mesenchymal transition, and cell adhesion. Our study provides novel insights into the oncofetal chondroitin sulfate biosynthesis regulation and identifies promising targets and biomarkers of immunotherapy for CRC and malaria in pregnancy.

Immunotherapy of cancer in single-cell RNA sequencing era: A precision medicine perspective

Immunotherapy has revolutionized cancer treatment and brought new aspects into tumor immunology. Effective immunotherapy will require using the suitable target antigens, optimizing the interaction between the antigenic peptide, the APC, and the T cell, and the simultaneous inhibitor of the negative regulatory process that inhibits immunotherapeutic effects and develop resistance. Tumor heterogeneity and its microenvironment is the leading cause of resistance in patients. Recently by emerging the single-cell RNA sequencing technology and its combination with immunotherapy, now we can specifically evaluate the mechanism of tumors in the face of immunotherapy agents at the single-cell resolution by detecting the transcriptional activity of immune checkpoints, screening neoantigens with high transcription levels, identifying rare cells, and other important processes. This review focuses on scRNA-seq, particularly on its application in cancer immunotherapy.

Combination of GNRs-PEI/cGAMP-laden macrophages-based photothermal induced in situ tumor vaccines and immune checkpoint blockade for synergistic anti-tumor immunotherapy

Immunotherapy is an effective strategy to control and eliminate primary and metastatic tumor by restarting and restoring the specific anti-tumor immune response. However, tumor immunotherapy often showed limited efficacy due to the poor T cell responses in vivo and the tumor suppressive microenvironments. Herein, we constructed polyethyleimine modified gold nanorods (GNRs-PEI) by conjugating PEI to GNRs via SAu bonds. GNRs-PEI/cGAMP nanoparticles were formed via electrostatic interaction and then loaded by macrophages. The GNRs-PEI/cGAMP-laden macrophages (GPc-RAWs) were intravenously injected into the tumor bearing mice and the in situ tumor vaccines were obtained after NIR irradiation. Besides, anti-PD-L1 antibody, an immune checkpoint inhibitor, was introduced to reverse immunosuppressive microenvironment and assisted to achieve the synergistic anti-tumor immunotherapy. GNRs-PEI/cGAMP-laden macrophages with NIR irradiation could effectively inhibit the primary tumors, while little effect for the contralateral tumors. When combined with anti-PD-L1 antibody, the combined strategy not only inhibited the growth of primary tumor, but also significantly delayed the proliferation of the contralateral tumors. More importantly, this strategy reversed immunosuppressive microenvironment without obvious side effects. Therefore, this study provided a great immunotherapy platform for the efficient treatment of primary and metastatic tumors.

The protein 4.1R downregulates VEGFA in M2 macrophages to inhibit colon cancer metastasis

M2 macrophages are crucial components of the tumour microenvironment and have been shown to be closely related to tumour progression. Co-culture with 4.1R^-/- M2 macrophages enhances the malignancy of colon cancer (CC), but the mechanism remains unclear. Here, we report that protein 4.1R knockout reduced the phagocytosis of M2 macrophages (M-CSF/IL-4-treated bone marrow cells) and promoted MC38 colon cancer cell proliferation, migration, invasion, tumour formation and epithelial-mesenchymal transition (EMT), which are regulated by M2 macrophages. Further mechanistic dissection revealed that the 4.1R knockout upregulated vascular endothelial growth factor A (VEGFA) secreted by M2 macrophages and promoted colon cancer progression by activating the PI3K/AKT signalling pathway. In summary, our present study identified that 4.1R downregulates VEGFA secretion in M2 macrophages and delays the malignant potential of colon cancer by inhibiting the PI3K/AKT signalling pathway.

circRNAs: Insight Into Their Role in Tumor-Associated Macrophages

Currently, it is well known that the tumor microenvironment not only provides energy support for tumor growth but also regulates tumor signaling pathways and promotes the proliferation, invasion, metastasis, and drug resistance of tumor cells. The tumor microenvironment, especially the function and mechanism of tumor-associated macrophages (TAMs), has attracted great attention. TAMs are the most common immune cells in the tumor microenvironment and play a vital role in the occurrence and development of tumors. circular RNA (circRNA) is a unique, widespread, and stable form of non-coding RNA (ncRNA), but little is known about the role of circRNAs in TAMs or how TAMs affect circRNAs. In this review, we summarize the specific manifestations of circRNAs that affect the tumor-associated macrophages and play a significant role in tumor progression. This review helps improve our understanding of the association between circRNAs and TAMs, thereby promoting the development and progress of potential clinical targeted therapies.

Double Strike Approach for Tumor Attack: Engineering T Cells Using a CD40L:CD28 Chimeric Co-Stimulatory Switch Protein for Enhanced Tumor Targeting in Adoptive Cell Therapy

Activation of co-stimulatory pathways in cytotoxic T lymphocytes expressing chimeric antigen receptors (CARs) have proven to boost effector activity, tumor rejection and long-term T cell persistence. When using antigen-specific T cell receptors (TCR) instead of CARs, the lack of co-stimulatory signals hampers robust antitumoral response, hence limiting clinical efficacy. In solid tumors, tumor stroma poses an additional hurdle through hindrance of infiltration and active inhibition. Our project aimed at generating chimeric co-stimulatory switch proteins (CSP) consisting of intracellular co-stimulatory domains (ICD) fused to extracellular protein domains (ECD) for which ligands are expressed in solid tumors. The ECD of CD40L was selected for combination with the ICD from the CD28 protein. With this approach, it was expected to not only provide co-stimulation and strengthen the TCR signaling, but also, through the CD40L ECD, facilitate the activation of tumor-resident antigen-presenting cells (APCs), modulate activation of tumor endothelium and induce TCR-MHC independent apoptotic effect on tumor cells. Since CD28 and CD40L belong to different classes of transmembrane proteins (type I and type II, respectively), creating a chimeric protein presented a structural and functional challenge. We present solutions to this challenge describing different CSP formats that were successfully expressed in human T cells along with an antigen-specific TCR. The level of surface expression of the CSPs depended on their distinct design and the state of T cell activation. In particular, CSPs were upregulated by TCR stimulation and downregulated following interaction with CD40 on target cells. Ligation of the CSP in the context of TCR-stimulation modulated intracellular signaling cascades and led to improved TCR-induced cytokine secretion and cytotoxicity. Moreover, the CD40L ECD exhibited activity as evidenced by effective maturation and activation of B cells and DCs. CD40L:CD28 CSPs are a new type of switch proteins designed to exert dual beneficial antitumor effect by acting directly on the gene-modified T cells and simultaneously on tumor cells and tumor-supporting cells of the TME. The observed effects suggest that they constitute a promising tool to be included in the engineering process of T cells to endow them with complementary features for improved performance in the tumor milieu.

M2 macrophage microvesicle-inspired nanovehicles improve accessibility to cancer cells and cancer stem cells in tumors

Cancer cells and cancer stem cells (CSCs) are the major players of cancer malignancy and metastasis, but they are extremely difficult to access. Inspired by the vital role of macrophages and microvesicle-mediated cell–cell communication in tumors, we herein designed M2 macrophage microvesicle-inspired nanovehicle of cabazitaxel (M-CFN) to promote accessibility to cancer cells and CSCs in tumors. In the 4T1 tumor model, M-CFN flexibly permeated the tumor mass, accessed cancer cells and CD90-positive cells, and significantly promoted their entry into CSC fractions in tumors. Moreover, M-CFN treatment profoundly eliminated aldehyde dehydrogenase (ALDH)-expressing CSCs in 4T1 and MCF-7 tumors, produced notable depression of tumor growth and caused 93.86% suppression of lung metastasis in 4T1 models. Therefore, the M2 macrophage microvesicle-inspired nanovehicle provides an encouraging strategy to penetrate the tumor tissues and access these insult cells in tumors for effective cancer therapy.

Combination of Nanomaterials in Cell-Based Drug Delivery Systems for Cancer Treatment

Cell-based drug delivery systems have shown tremendous advantages in cancer treatment due to their distinctive properties. For instance, delivery of therapeutics using tumor-tropic cells like neutrophils, lymphocytes and mesenchymal stem cells can achieve specific tumor targeting due to the "Trojan Horse" effect. Other circulatory cells like erythrocytes and platelets can greatly improve the circulation time of nanoparticles due to their innate long circulation property. Adipocytes, especially cancer-associated adipocytes, play key roles in tumor development and metabolism, therefore, adipocytes are regarded as promising bio-derived nanoplatforms for anticancer targeted drug delivery. Nanomaterials are important participants in cell-based drug delivery because of their unique physicochemical characteristics. Therefore, the integration of various nanomaterials with different cell types will endow the constructed delivery systems with many attractive properties due to the merits of both. In this review, a number of strategies based on nanomaterial-involved cell-mediated drug delivery systems for cancer treatment will be summarized. This review discusses how nanomaterials can be a benefit to cell-based therapies and how cell-derived carriers overcome the limitations of nanomaterials, which highlights recent advancements and specific biomedical applications based on nanomaterial-mediated, cell-based drug delivery systems.

Modulation of Immune Components on Stem Cell and Dormancy in Cancer

Cancer stem cells (CSCs) refer to a certain subpopulation within the tumor entity that is characterized by restricted cellular proliferation and multipotent differentiation potency. The existence of CSCs has been proven to contribute to the heterogeneity of malignancies, accounting for intensified tumorigenesis, treatment resistance, and metastatic spread. Dormancy was proposed as a reversible state of cancer cells that are temporarily arrested in the cell cycle, possessing several hallmarks that facilitate their survival within a devastating niche. This transient period is evoked to enter an actively proliferating state by multiple regulatory alterations, and one of the most significant and complex factors comes from local and systemic inflammatory reactions and immune components. Although CSCs and dormant cancer cells share several similarities, the clear relationship between these two concepts remains unclear. Thus, the detailed mechanism of immune cells interacting with CSCs and dormant cancer cells also warrants elucidation for prevention of cancer relapse and metastasis. In this review, we summarize recent findings and prospective studies on CSCs and cancer dormancy to conclude the relationship between these two concepts. Furthermore, we aim to outline the mechanism of immune components in interfering with CSCs and dormant cancer cells to provide a theoretical basis for the prevention of relapse and metastasis.

Phototherapy of Brain Tumours Using a Fibre Optic Neurosystem

In this work, a new approach was tested to assess the cellular composition of tissues by time-resolved methods of fluorescence analysis of exogenous and endogenous fluorophores. First of all, the differences in fluorescence kinetics of endogenous fluorophores (coenzymes NADH and FAD) in tumour and immunocompetent cells were determined. After that, differences in fluorescence kinetics of photosensitizer 5 ALA-induced protoporphyrin IX were established due to its different metabolism in cells of different phenotypes. Kinetics of photoluminescence of NADH and FAD coenzymes as well as photosensitizer were studied by means of two different methods: time-resolved spectroscopy based on a streak-camera and fibre optic neuroscopy, which served to perform process monitoring and regular fluorescence diagnosis of the probed region. Time-resolved fluorescence microscopy (FLIM) was used as a control technique. Time-resolved spectroscopic fluorescence lifetime analysis was performed on sexually mature female rats induced with glioma C6 brain tumour under in vivo conditions; thus, under conditions where the immune system actively intervenes in the process of oncogenesis. In this regard, the aim of the study was to recognize the cellular composition of the brain tumour tissue, namely the ratio of cancer and immunocompetent cells and their mutual localization. Understanding the role of the immune system thus provides new ways and approaches for further diagnosis and therapy, making tumour-associated immune cells a prime target for modern therapies.

Macrophage-tumor chimeric exosomes accumulate in lymph node and tumor to activate the immune response and the tumor microenvironment

[Figure: see text].

Next frontier in tumor immunotherapy: macrophage-mediated immune evasion

Tumor-associated macrophages (TAMs), at the core of immunosuppressive cells and cytokines networks, play a crucial role in tumor immune evasion. Increasing evidences suggest that potential mechanisms of macrophage-mediated tumor immune escape imply interpretation and breakthrough to bottleneck of current tumor immunotherapy. Therefore, it is pivotal to understand the interactions between macrophages and other immune cells and factors for enhancing existing anti-cancer treatments. In this review, we focus on the specific signaling pathways through which TAMs involve in tumor antigen recognition disorders, recruitment and function of immunosuppressive cells, secretion of immunosuppressive cytokines, crosstalk with immune checkpoints and formation of immune privileged sites. Furthermore, we summarize correlative pre-clinical and clinical studies to provide new ideas for immunotherapy. From our perspective, macrophage-targeted therapy is expected to be the next frontier of cancer immunotherapy.

Characterization of Molecular Subtypes in Head and Neck Squamous Cell Carcinoma With Distinct Prognosis and Treatment Responsiveness

Head and neck squamous cell carcinoma (HNSCC) is one of the most aggressive malignancies with complex phenotypic, etiological, biological, and clinical heterogeneities. Previous studies have proposed different clinically relevant subtypes of HNSCC, but little is known about its corresponding prognosis or suitable treatment strategy. Here, we identified 101 core genes from three prognostic pathways, including mTORC1 signaling, unfold protein response, and UV response UP, in 124 pairs of tumor and matched normal tissues of HNSCC. Moreover, we identified three robust subtypes associated with distinct molecular characteristics and clinical outcomes using consensus clustering based on the gene expression profiles of 944 HNSCC patients from four independent datasets. We then integrated the genomic information of The Cancer Genome Atlas (TCGA) HNSCC cohort to comprehensively evaluate the molecular features of different subtypes and screen for potentially effective therapeutic agents. Cluster 1 had more arrested oncogenic signaling, the highest immune cell infiltration, the highest immunotherapy and chemotherapeutic responsiveness, and the best prognosis. By contrast, Cluster 3 showed more activated oncogenic signaling, the lowest immune cell infiltration, the lowest immunotherapy and chemotherapy responsiveness, and the worst prognosis. Our findings corroborate the molecular diversity of HNSCC tumors and provide a novel classification strategy that may guide for prognosis and treatment allocation.

Empowering patients from within: Emerging nanomedicines for in vivo immune cell reprogramming

Currently, medicine lacks the ability to reprogram selected immune cells so they possess all the functions which, from a clinical standpoint, physicians might wish them to have. To solve this problem, scientists have been marrying concepts from materials science, immunology, and genetic engineering to develop novel nanotherapeutics that directly genetically reprogram immune cells inside the body. These products could address key limitations of existing ex vivo-engineered cell immunotherapies and substantially enhance patient access and outcomes. This review highlights the latest advances in this rapidly emerging biotech field and discusses challenges in translating these preclinical studies into successful clinical nanomedicines.

Nanobiotechnology and Immunotherapy: Two Powerful and Cooperative Allies against Cancer

A number of novel cancer therapies have recently emerged that have rapidly moved from the bench to the clinic. Onco-immunotherapies, such as immune checkpoint blockade inhibitors and adoptive cell therapies, have revolutionized the field, since they provide a way to induce strong anti-tumor immune responses, which are able to fight cancer effectively. However, despite showing great efficacy in hematological and some solid tumors, unresponsiveness, development of therapy resistance and the development of serious adverse effects, limit their capacity to impact the vast majority of tumors. Nanoparticle-based delivery systems are versatile vehicles for a wide variety of molecular cargoes and provide an innovative strategy to improve conventional onco-immunotherapies. They can be finely tuned to release their contents in the tumor microenvironment, or to deliver combinations of adjuvants and antigens in the case of nanovaccines. In this review, we summarize the recent advancements in the field of nanobiotechnology, to remodel the tumor microenvironment and to enhance immunotherapies.

Exploiting Single-Cell Tools in Gene and Cell Therapy

Single-cell molecular tools have been developed at an incredible pace over the last five years as sequencing costs continue to drop and numerous molecular assays have been coupled to sequencing readouts. This rapid period of technological development has facilitated the delineation of individual molecular characteristics including the genome, transcriptome, epigenome, and proteome of individual cells, leading to an unprecedented resolution of the molecular networks governing complex biological systems. The immense power of single-cell molecular screens has been particularly highlighted through work in systems where cellular heterogeneity is a key feature, such as stem cell biology, immunology, and tumor cell biology. Single-cell-omics technologies have already contributed to the identification of novel disease biomarkers, cellular subsets, therapeutic targets and diagnostics, many of which would have been undetectable by bulk sequencing approaches. More recently, efforts to integrate single-cell multi-omics with single cell functional output and/or physical location have been challenging but have led to substantial advances. Perhaps most excitingly, there are emerging opportunities to reach beyond the description of static cellular states with recent advances in modulation of cells through CRISPR technology, in particular with the development of base editors which greatly raises the prospect of cell and gene therapies. In this review, we provide a brief overview of emerging single-cell technologies and discuss current developments in integrating single-cell molecular screens and performing single-cell multi-omics for clinical applications. We also discuss how single-cell molecular assays can be usefully combined with functional data to unpick the mechanism of cellular decision-making. Finally, we reflect upon the introduction of spatial transcriptomics and proteomics, its complementary role with single-cell RNA sequencing (scRNA-seq) and potential application in cellular and gene therapy.