Immunoregulatory Roles of Extracellular Vesicles and Associated Therapeutic Applications in Lung Cancer

Strategies for Small Extracellular Vesicle-Based Cancer Immunotherapy

Extracellular vesicles (EVs) are lipid bilayer-enclosed vesicles released by cells. EVs encapsulate proteins and nucleic acids of their parental cell and efficiently deliver the cargo to recipient cells. These vesicles act as mediators of intercellular communication and thus play a crucial role in various physiological and pathological processes. Moreover, EVs hold promise for clinical use. They have been explored as drug delivery vehicles, therapeutic agents, and targets for disease diagnosis. In the landscape of cancer research, while strides have been made in EV-focused cancer physiopathology, liquid biopsy, and drug delivery, the exploration of EVs as immunotherapeutic agents may not have seen substantial progress to date. Despite promising findings reported in cell and animal studies, the clinical translation of EV-based cancer immunotherapeutics encounters challenges. Here, we review the existing strategies used in EV-based cancer immunotherapy, aiming to propel the development of this emerging yet crucial field.

Extracellular vesicles biogenesis and uptake concepts: A comprehensive guide to studying host-pathogen communication

The study of host-pathogen interactions has increased considerably in recent decades. This intercellular communication has been mediated by extracellular vesicles (EVs) that play an important role during the interaction. EVs are particles of lipid bilayer and described in different types of cells, eukaryotic or prokaryotic. Depending on their biogenesis they are described as exosomes (derived from multivesicular bodies) and microvesicles (derived from the plasma membrane). The EVs carry biomolecules, including nucleic acids, lipids, and proteins that can be released or internalized by other cells in different pathways (endocytosis, macropinocytosis, phagocytosis, or membrane fusion) in the process described as uptake. The balance between biogenesis and uptake of EVs could modify physiological and pathophysiological processes of the cell. This review is focusing on the dynamic roles of release and capture of EVs during host-pathogen interaction. We also do a critical analysis of methodologies for obtaining and analyzing EVs. Finally, we draw attention to critical points to be considered in EV biogenesis and uptake studies.

The role of extracellular vesicles in non-small-cell lung cancer, the unknowns, and how new approach methodologies can support new knowledge generation in the field

Extracellular vesicles (EVs) are nanosized particles released from most human cell types that contain a variety of cargos responsible for mediating cell-to-cell and organ-to-organ communications. Current knowledge demonstrates that EVs also play critical roles in many aspects of the progression of Non-Small-Cell Lung Cancer (NSCLC). Their roles range from increasing proliferative signalling to inhibiting apoptosis, promoting cancer metastasis, and modulating the tumour microenvironment to support cancer development. However, due to the limited availability of patient samples, intrinsic inter-species differences between human and animal EV biology, and the complex nature of EV interactions in vivo, where multiple cell types are present and several events occur simultaneously, the use of conventional preclinical and clinical models has significantly hindered reaching conclusive results. This review discusses the biological roles that EVs are currently known to play in NSCLC and identifies specific challenges in advancing today's knowledge. It also describes the NSCLC models that have been used to define currently-known EV functions, the limitations associated with their use in this field, and how New Approach Methodologies (NAMs), such as microfluidic platforms, organoids, and spheroids, can be used to overcome these limitations, effectively supporting future exciting discoveries in the NSCLC field and the potential clinical exploitation of EVs.

Surface-Engineered Extracellular Vesicles in Cancer Immunotherapy

Extracellular vesicles (EVs) are lipid bilayer-enclosed bodies secreted by all cell types. EVs carry bioactive materials, such as proteins, lipids, metabolites, and nucleic acids, to communicate and elicit functional alterations and phenotypic changes in the counterpart stromal cells. In cancer, cells secrete EVs to shape a tumor-promoting niche. Tumor-secreted EVs mediate communications with immune cells that determine the fate of anti-tumor therapeutic effectiveness. Surface engineering of EVs has emerged as a promising tool for the modulation of tumor microenvironments for cancer immunotherapy. Modification of EVs' surface with various molecules, such as antibodies, peptides, and proteins, can enhance their targeting specificity, immunogenicity, biodistribution, and pharmacokinetics. The diverse approaches sought for engineering EV surfaces can be categorized as physical, chemical, and genetic engineering strategies. The choice of method depends on the specific application and desired outcome. Each has its advantages and disadvantages. This review lends a bird's-eye view of the recent progress in these approaches with respect to their rational implications in the immunomodulation of tumor microenvironments (TME) from pro-tumorigenic to anti-tumorigenic ones. The strategies for modulating TME using targeted EVs, their advantages, current limitations, and future directions are discussed.

Engineered Microparticles for Treatment of Murine Brain Metastasis by Reprograming Tumor Microenvironment and Inhibiting MAPK Pathway

Brain metastases (BRM) are common in advanced lung cancer. However, their treatment is challenging due to the blood-brain barrier (BBB) and the immunosuppressive tumor microenvironment (ITME). Microparticles (MPs), a type of extracellular vesicle, can serve as biocompatible drug delivery vehicles that can be further modulated with genetic engineering techniques. MPs prepared from cells induced with different insults are compared and it is found that radiation-treated cell-released microparticles (RMPs) achieve optimal targeting and macrophage activation. The enzyme ubiquitin-specific protease 7 (USP7), which simultaneously regulates tumor growth and reprograms M2 macrophages (M2Φ), is found to be expressed in BRM. Engineered RMPs are then constructed that comprise: 1) the RMP carrier that targets and reprograms M2Φ; 2) a genetically expressed SR-B1-targeting peptide for improved BBB permeability; and 3) a USP7 inhibitor to kill tumor cells and reprogram M2Φ. These RMPs successfully cross the BBB and target M2Φ in vitro and in vivo in mice, effectively reprogramming M2Φ and improving survival in a murine BRM model. Therapeutic effects are further augmented when combined with immune checkpoint blockade. This study provides proof-of-concept for the use of genetically engineered MPs for the treatment of BRM.

Extracellular Vesicles in Lung Cancer: Bystanders or Main Characters?

Lung cancer still represents the main cause of cancer death worldwide. The poor survival is mainly related to the diagnosis which is often obtained in advanced stages when the disease is unresectable and characterized by the worst prognosis. Only in the last decades have great discoveries led to the development of new therapies targeted to oncogenes and to boost the host immune response against the tumor. Tumor identification and molecular/immunological characterization rely on bioptic samples which represent the gold standard for diagnosis. Nonetheless, less invasive procedures providing small samples will be more and more common in the future. Extracellular vesicles (EV), submicron particles released by any cell type, are candidates for diagnostic and prognostic biomarkers. EV are mediators of intercellular communication and can convey cytokines, miRNAs, antigens, and many other factors of tumorigenesis. This review summarizes the most appealing findings on lung-cancer-related EV, debating the evidence on circulating versus airway EV as potential biomarkers in disease management and the main studies on the role of these particles on lung cancer pathogenesis. Overall, the available results point toward a wide range of possible applications, supported by the promising achievements of genotyping on BAL fluid EV and proteomic analysis on pleural effusion EV. Nonetheless, the study of lung EV is still affected by remarkable methodological issues, especially when in vitro evidence is translated into humans. Whether EV still represent an "information fog" or can be useful in lung cancer management will be discussed, with possible hints on how to improve their usage.

Current status of and progress in the treatment of malignant pleural effusion of lung cancer

Malignant pleural effusion (MPE) is a common complication in the late stage of malignant tumors. The appearance of MPE indicates that the primary tumor has spread to the pleura or progressed to an advanced stage. The survival time of the patients will be significantly shortened, with a median survival of only a few months. There are a variety of traditional treatments, and their advantages and disadvantages are relatively clear. There are still many problems that cannot be solved by traditional methods in clinical work. The most common one is intrapleural perfusion therapy with chemotherapy drugs, but it has a large side effect of chemotherapy. At present, with the development of medical technology, there are a variety of treatment methods, and many innovative, significant and valuable treatment methods have emerged, which also bring hope for the treatment of refractory and recurrent MPE patients. Several clinical trials had confirmed that drug-carrying microparticles has less adverse reactions and obvious curative effect. However, there is still a long way to go to completely control and cure MPE, and the organic combination of clinical work and scientific research results is needed to bring dawn to refractory MPE patients.

Synergies of Extracellular Vesicles and Microchimerism in Promoting Immunotolerance During Pregnancy

The concept of biological identity has been traditionally a central issue in immunology. The assumption that entities foreign to a specific organism should be rejected by its immune system, while self-entities do not trigger an immune response is challenged by the expanded immunotolerance observed in pregnancy. To explain this "immunological paradox", as it was first called by Sir Peter Medawar, several mechanisms have been described in the last decades. Among them, the intentional transfer and retention of small amounts of cells between a mother and her child have gained back attention. These microchimeric cells contribute to expanding allotolerance in both organisms and enhancing genetic fitness, but they could also provoke aberrant alloimmune activation. Understanding the mechanisms used by microchimeric cells to exert their function in pregnancy has proven to be challenging as per definition they are extremely rare. Profiting from studies in the field of transplantation and cancer research, a synergistic effect of microchimerism and cellular communication based on the secretion of extracellular vesicles (EVs) has begun to be unveiled. EVs are already known to play a pivotal role in feto-maternal tolerance by transferring cargo from fetal to maternal immune cells to reshape their function. A further aspect of EVs is their function in antigen presentation either directly or on the surface of recipient cells. Here, we review the current understanding of microchimerism in the feto-maternal tolerance during human pregnancy and the potential role of EVs in mediating the allorecognition and tropism of microchimeric cells.

Cancer Stem Cells (CSCs), Circulating Tumor Cells (CTCs) and Their Interplay with Cancer Associated Fibroblasts (CAFs): A New World of Targets and Treatments

Simple Summary

The world of small molecules in solid tumors as cancer stem cells (CSCs), circulating tumor cells (CTCs) and cancer-associated fibroblasts (CAFs) continues to be under-debated, but not of minor interest in recent decades. One of the main problems in regard to cancer is the development of tumor recurrence, even in the early stages, in addition to drug resistance and, consequently, ineffective or an incomplete response against the tumor. The findings behind this resistance are probably justified by the presence of small molecules such as CSCs, CTCs and CAFs connected with the tumor microenvironment, which may influence the aggressiveness and the metastatic process. The mechanisms, connections, and molecular pathways behind them are still unknown. Our review would like to represent an important step forward to highlight the roles of these molecules and the possible connections among them.

Abstract

The importance of defining new molecules to fight cancer is of significant interest to the scientific community. In particular, it has been shown that cancer stem cells (CSCs) are a small subpopulation of cells within tumors with capabilities of self-renewal, differentiation, and tumorigenicity; on the other side, circulating tumor cells (CTCs) seem to split away from the primary tumor and appear in the circulatory system as singular units or clusters. It is becoming more and more important to discover new biomarkers related to these populations of cells in combination to define the network among them and the tumor microenvironment. In particular, cancer-associated fibroblasts (CAFs) are a key component of the tumor microenvironment with different functions, including matrix deposition and remodeling, extensive reciprocal signaling interactions with cancer cells and crosstalk with immunity. The settings of new markers and the definition of the molecular connections may present new avenues, not only for fighting cancer but also for the definition of more tailored therapies.

Extracellular Vesicles and Interleukins: Novel Frontiers in Diagnostic and Therapeutic for Cancer

Tumor cells present many strategies for survival and dissemination in the tumor environment. Extracellular vesicles are a vital pathway used in crosstalk between tumor and non-malignant cells. They carry different types of molecules that, when internalized by target cells, can activate signaling pathways and molecular processes that will promote and disseminate neoplastic cells. Proteins, nucleic acids, and different cytokines, such as interleukins, are the main classes of molecules carried by extracellular vesicles and are being studied to understand the molecular mechanisms present in the tumor microenvironment. In particular, although poorly understood, the association between EVs and interleukins has revealed potential approaches to the diagnosis and therapeutics of several neoplasms.

Commensal and Pathogenic Bacterial-Derived Extracellular Vesicles in Host-Bacterial and Interbacterial Dialogues: Two Sides of the Same Coin

Extracellular vesicles (EVs) cause effective changes in various domains of life. These bioactive structures are essential to the bidirectional organ communication. Recently, increasing research attention has been paid to EVs derived from commensal and pathogenic bacteria in their potential role to affect human disease risk for cancers and a variety of metabolic, gastrointestinal, psychiatric, and mental disorders. The present review presents an overview of both the protective and harmful roles of commensal and pathogenic bacteria-derived EVs in host-bacterial and interbacterial interactions. Bacterial EVs could impact upon human health by regulating microbiota–host crosstalk intestinal homeostasis, even in distal organs. The importance of vesicles derived from bacteria has been also evaluated regarding epigenetic modifications and applications. Generally, the evaluation of bacterial EVs is important towards finding efficient strategies for the prevention and treatment of various human diseases and maintaining metabolic homeostasis.

Secretions from hypochlorous acid-treated tumor cells delivered in a melittin hydrogel potentiate cancer immunotherapy

Autologous tumor cells and cell-derived secretions (CDS) can induce antitumor immune responses. The conditions in which cells are cultured and treated impact CDS, and cellular insults alter their composition and function. In this study, we generated CDS from tumor cells exposed to normal culture conditions, hypoxia, cisplatin, radiotherapy, photodynamic therapy, or hypochlorous acid (HOCl). In vitro HOCl-CDS showed the strongest stimulatory effects on dendritic cells and macrophages compared to CDS generated by hypoxia, cisplatin, radiotherapy or photodynamic therapy. To improve HOCl-CDS activity at the tumor site, we loaded HOCl-CDS into a melittin-encapsulated hydrogel scaffold. When injected intratumorally, the HOCl-CDS hydrogel promoted tumor cell death, cytotoxic T lymphocyte infiltration, and tumor-associated macrophage reprogramming towards an M1 phenotype. The hydrogel inhibited tumor growth and prolonged the survival of mice bearing B16–F10 melanoma. Furthermore, hydrogel-delivered HOCl-CDS augmented the antitumor effects of immune checkpoint blockade. These results underscore the importance of the CDS generation method and delivery approach for improving cancer immunotherapy.

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HOCl-treated tumor cell-derived secretions (HOCl-CDS) is a robust immune-stimulator on dendritic cells and macrophages.

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A multifunctional HOCl-CDS hydrogel was developed by loading HOCl-CDS into a melittin-encapsulated hydrogel scaffold.

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HOCl-CDS hydrogel promoted tumor cell death, cytotoxic T lymphocyte infiltration and M1-TAM polarization in mice.

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HOCl-CDS hydrogel synergistically augmented the therapeutic effect of anti-PD-1 and further potentiated cancer immunotherapy.

The Role of Extracellular Vesicles from Human Macrophages on Host-Pathogen Interaction

The nano-sized membrane enclosed extracellular vesicles (EVs) released by virtually all cell types play an essential role in intercellular communication via delivering bio-molecules, such as nucleic acids, proteins, lipids, and other molecules to recipient cells. By mediating an active and steady-state cell-to-cell communication, EVs contribute to regulating and preserving cellular homeostasis. On the other hand, EVs can also spread pathogen-derived molecules during infections, subverting the host immune responses during infections and thus worsening pathophysiological processes. In recent years, the biological functioning of EVs has become a widespread research field in basic and clinical branches of medical sciences due to their potential role in therapeutic applications for several diseases. This review aims to summarize the main recent findings regarding the implication of EVs shed by human macrophages (MΦ-EVs) and how they can modulate the host immune response to control or increase the damage caused by infectious agents. We will also present the methods used to describe MΦ-EVs, as well as the potential of these EVs as disease diagnostic tools for some human pathogens. We believe that an in-depth understanding of the host–pathogen interactions mediated by MΦ-EVs may trigger the development of innovative therapeutic strategies against infectious diseases.

Development of Extracellular Vesicle Therapeutics: Challenges, Considerations, and Opportunities

Extracellular vesicles (EVs) hold great promise as therapeutic modalities due to their endogenous characteristics, however, further bioengineering refinement is required to address clinical and commercial limitations. Clinical applications of EV-based therapeutics are being trialed in immunomodulation, tissue regeneration and recovery, and as delivery vectors for combination therapies. Native/biological EVs possess diverse endogenous properties that offer stability and facilitate crossing of biological barriers for delivery of molecular cargo to cells, acting as a form of intercellular communication to regulate function and phenotype. Moreover, EVs are important components of paracrine signaling in stem/progenitor cell-based therapies, are employed as standalone therapies, and can be used as a drug delivery system. Despite remarkable utility of native/biological EVs, they can be improved using bio/engineering approaches to further therapeutic potential. EVs can be engineered to harbor specific pharmaceutical content, enhance their stability, and modify surface epitopes for improved tropism and targeting to cells and tissues in vivo. Limitations currently challenging the full realization of their therapeutic utility include scalability and standardization of generation, molecular characterization for design and regulation, therapeutic potency assessment, and targeted delivery. The fields' utilization of advanced technologies (imaging, quantitative analyses, multi-omics, labeling/live-cell reporters), and utility of biocompatible natural sources for producing EVs (plants, bacteria, milk) will play an important role in overcoming these limitations. Advancements in EV engineering methodologies and design will facilitate the development of EV-based therapeutics, revolutionizing the current pharmaceutical landscape.

Extracellular Vesicles in Lung Cancer: Prospects for Diagnostic and Therapeutic Applications

Extracellular vesicles (EVs) are nano-sized lipid-bound particles containing proteins, nucleic acids and metabolites released by cells. They have been identified in body fluids including blood, saliva, sputum and pleural effusions. In tumors, EVs derived from cancer and immune cells mediate intercellular communication and exchange, and can affect immunomodulatory functions. In the context of lung cancer, emerging evidence implicates EV involvement during various stages of tumor development and progression, including angiogenesis, epithelial to mesenchymal transformation, immune system suppression, metastasis and drug resistance. Additionally, tumor-derived EVs (TDEs) have potential as a liquid biopsy source and as a means of therapeutic targeting, and there is considerable interest in developing clinical applications for EVs in these contexts. In this review, we consider the biogenesis, components, biological functions and isolation methods of EVs, and the implications for their clinical utility for diagnostic and therapeutic applications in lung cancer.

A systematic review of extracellular vesicles as non-invasive biomarkers in glioma diagnosis, prognosis, and treatment response monitoring

The present systematic review was done to investigate the possible application of Extracellular vesicles (EVs) in the diagnosis, prognosis, and treatment response monitoring of gliomas using available literature to wrap up the final applicable conclusion in this regard. we searched PubMed/MEDLINE, Scopus, and ISI Web of Science databases. Authors evaluated the quality of the included studies by the QUADAS-2 tool. In total, 2037 published datasets were retrieved through systematic search. Upon screening for eligibility, 35 datasets were determined as eligible. Exosome was the EV-subtype described in the majority of studies, and most datasets used serum as the primary EVs isolation source. EVs isolation was primarily conducted by ultracentrifugation. 31 datasets reported that EVs hold considerable potential for being used in diagnostics, with the majority reporting different types of miRNAs as biomarkers. Besides, 8 datasets reported that EVs could be a potential source of prognostic biomarkers. And finally, 3 datasets reported that EVs might be a reliable strategy for monitoring therapy response in glioma patients. According to the findings of the current systematic review, it seems that miR-301, miR-21, and HOTAIR had the highest diagnostic accuracy. However, heterogeneous and limited evidence regarding prognosis and treatment response monitoring precludes us from drawing a practical conclusion regarding EVs.

MicroRNA-449a delays lung cancer development through inhibiting KDM3A/HIF-1α axis

Background

It has been established that microRNA (miR)-449a is anti-tumorigenic in cancers, including lung cancer. Therefore, this study further explored miR-449a-mediated mechanism in lung cancer, mainly focusing on lysine demethylase 3A/hypoxia-induced factor-1α (KDM3A/HIF-1α) axis.

Methods

miR-449a, KDM3A and HIF-1α levels in lung cancer tissues and cell lines (A549, H1299 and H460) were measured. Loss- and gain-of-function assays were performed and then cell proliferation, cell cycle, apoptosis, invasion and migration were traced. The relationship between KDM3A, miR-449a and HIF-1α was verified. Tumor growth in vivo was also monitored.

Results

Both lung cancer tissues and cells exhibited reduced miR-449a and raised KDM3A and HIF-1α levels. miR-449a interacted with KDM3A; HIF-1α could bind with KDM3A. Up-regulating miR-449a hindered while suppressing miR-449a induced lung cancer development via mediating HIF-1α. Elevating KDM3A promoted cellular aggression while down-regulating KDM3A had the opposite effects. Up-regulating KDM3A or HIF-1α negated up-regulated miR-449a-induced effects on cellular growth in lung cancer. Restoring miR-449a impaired tumorigenesis in vivo in lung cancer.

Conclusion

It is eventually concluded that miR-449a delays lung cancer development through suppressing KDM3A/HIF-1α axis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-02881-8.

Extracellular Vesicle Transportation and Uptake by Recipient Cells: A Critical Process to Regulate Human Diseases

Emerging evidence highlights the relevance of extracellular vesicles (EVs) in modulating human diseases including but not limited to cancer, inflammation, and neurological disorders. EVs can be found in almost all types of human body fluids, suggesting that their trafficking may allow for their targeting to remote recipient cells. While molecular processes underlying EV biogenesis and secretion are increasingly elucidated, mechanisms governing EV transportation, target finding and binding, as well as uptake into recipient cells remain to be characterized. Understanding the specificity of EV transport and uptake is critical to facilitating the development of EVs as valuable diagnostics and therapeutics. In this mini review, we focus on EV uptake mechanisms and specificities, as well as their implications in human diseases.