STAT3-regulated exosomal miR-21 promotes angiogenesis and is involved in neoplastic processes of transformed human bronchial epithelial cells

Role of Exosomes and its emerging therapeutic applications in the pathophysiology of Non-Infectious disease

Exosomes are a type of small Extracellular Vesicles (EVs) and play crucial roles in cancer and other diseases. Exosomes role in various diseases has been studied as they regulate intercellular communication and are obtained from almost any part of the body. Exosomes use is complicated in diseases as they promote pathogenesis but also act as a very good therapeutic agent in most diseases. The presence of a complex molecular cargo consisting of nucleic acids (DNA, RNA, miRNA, siRNA, etc.,) makes it a very good delivery agent and acts as a biomarker for many cancers, cardiovascular and neurodegenerative diseases. They can be used to selectively target cells and activate immune cell responses depending on the source obtained. Exosomes based immunotherapy is an area of gaining importance due to the proteins present in them and their specificity to the targeted cells. The role of exosomes in the diagnosis and treatment of non-infectious diseases is discussed in detail in this article.

Interleukin-17A mediates tobacco smoke-induced lung cancer epithelial-mesenchymal transition through transcriptional regulation of ΔNp63α on miR-19

Interleukin-17A (IL-17A) is an essential inflammatory cytokine in the progress of carcinogenesis. Tobacco smoke (TS) is a major risk factor of lung cancer that influences epithelial-mesenchymal transition (EMT) process. However, the potential mechanism by which IL-17A mediates the progression of lung cancer in TS-induced EMT remains elusive. In the present study, it was revealed that the IL-17A level was elevated in lung cancer tissues, especially in tumor tissues of cases with experience of smoking, and a higher IL-17A level was correlated with induction of EMT in those specimens. Moreover, the expression of ΔNp63α was increased in IL-17A-stimulated lung cancer cells. ΔNp63α functioned as a key oncogene that bound to the miR-17-92 cluster promoter and transcriptionally increased the expression of miR-19 in lung cancer cells. Overexpression of miR-19 promoted EMT in lung cancer with downregulation of E-cadherin and upregulation of N-cadherin, while its inhibition suppressed EMT. Finally, the upregulated levels of IL-17A, ΔNp63α, and miR-19 along with the alteration of EMT-associated biomarkers were found in lung tissues of TS-exposed mice. Taken together, the abovementioned results suggest that IL-17A increases ΔNp63α expression, transcriptionally elevates miR-19 expression, and promotes TS-induced EMT in lung cancer. These findings may provide a new insight for the identification of therapeutic targets for lung cancer.

Molecular functions and therapeutic applications of exosomal noncoding RNAs in cancer

Cancer is one of the most difficult diseases in human society. Therefore, it is urgent for us to understand its pathogenesis and improve the cure rate. Exosomes are nanoscale membrane vesicles formed by a variety of cells through endocytosis. As a new means of intercellular information exchange, exosomes have attracted much attention. Noncoding RNAs exist in various cell compartments and participate in a variety of cellular reactions; in particular, they can be detected in exosomes bound to lipoproteins and free circulating molecules. Increasing evidence has suggested the potential roles of exosomal noncoding RNAs in the progression of tumors. Herein, we present a comprehensive update on the biological functions of exosomal noncoding RNAs in the development of cancer. Specifically, we mainly focus on the effects of exosomal noncoding RNAs, including microRNAs, circular RNAs, long noncoding RNAs, small nuclear RNAs, and small nucleolar RNAs, on tumor growth, metastasis, angiogenesis, and chemoresistance. Moreover, we outline the current clinical implications concerning exosomal noncoding RNAs in cancer treatment.

Tumor-Derived Exosomes Modulate Primary Site Tumor Metastasis

Tumor-derived exosomes (TDEs) are actively produced and released by tumor cells and carry messages from tumor cells to healthy cells or abnormal cells, and they participate in tumor metastasis. In this review, we explore the underlying mechanism of action of TDEs in tumor metastasis. TDEs transport tumor-derived proteins and non-coding RNA to tumor cells and promote migration. Transport to normal cells, such as vascular endothelial cells and immune cells, promotes angiogenesis, inhibits immune cell activation, and improves chances of tumor implantation. Thus, TDEs contribute to tumor metastasis. We summarize the function of TDEs and their components in tumor metastasis and illuminate shortcomings for advancing research on TDEs in tumor metastasis.

Exosome-derived noncoding RNAs: Function, mechanism, and application in tumor angiogenesis

Exosomes are extracellular vesicles released by various cell types that perform various biological functions, mainly mediating communication between different cells, especially those active in cancer. Noncoding RNAs (ncRNAs), of which there are many types, were recently identified as enriched and stable in the exocrine region and play various roles in the occurrence and progression of cancer. Abnormal angiogenesis has been confirmed to be related to human cancer. An increasing number of studies have shown that exosome-derived ncRNAs play an important role in tumor angiogenesis. In this review, we briefly outline the characteristics of exosomes, ncRNAs, and tumor angiogenesis. Then, the mechanism of the impact of exosome-derived ncRNAs on tumor angiogenesis is analyzed from various angles. In addition, we focus on the regulatory role of exosome-derived ncRNAs in angiogenesis in different types of cancer. Furthermore, we emphasize the potential role of exosome-derived ncRNAs as biomarkers in cancer diagnosis and prognosis and therapeutic targets in the treatment of tumors.

Extracellular vesicles released by non-small cell lung cancer cells drive invasion and permeability in non-tumorigenic lung epithelial cells

Extracellular vesicles (EVs) released from non-small cell lung cancer (NSCLC) cells are known to promote cancer progression. However, it remains unclear how EVs from various NSCLC cells differ in their secretion profile and their ability to promote phenotypic changes in non-tumorigenic cells. Here, we performed a comparative analysis of EV release from non-tumorigenic cells (HBEC/BEAS-2B) and several NSCLC cell lines (A549, H460, H358, SKMES, and Calu6) and evaluated the potential impact of NSCLC EVs, including EV-encapsulated RNA (EV-RNA), in driving invasion and epithelial barrier impairment in HBEC/BEAS-2B cells. Secretion analysis revealed that cancer cells vary in their secretion level, with some cell lines having relatively low secretion rates. Differential uptake of NSCLC EVs was also observed, with uptake of A549 and SKMES EVs being the highest. Phenotypically, EVs derived from Calu6 and H358 cells significantly enhanced invasion, disrupted an epithelial barrier, and increased barrier permeability through downregulation of E-cadherin and ZO-1. EV-RNA was a key contributing factor in mediating these phenotypes. More nuanced analysis suggests a potential correlation between the aggressiveness of NSCLC subtypes and the ability of their respective EVs to induce cancerous phenotypes.

Exosomes of A549 Cells Induced Migration, Invasion, and EMT of BEAS-2B Cells Related to let-7c-5p and miR-181b-5p

As carriers containing abundant biological information, exosomes could deliver the property of donor cells to recipient cells. Emerging studies have shown that tumor cells could secrete a mass of exosomes into the microenvironment to regulate bystander cells. However, the underlying mechanisms of such a phenomenon remain largely unexplored. In this research, we purified and identified the exosomes of A549 cells and found that A549-cell-derived exosomes promoted BEAS-2B cells migration, invasion, and epithelial-mesenchymal transition (EMT). Importantly, we observed that let-7c-5p and miR-181b-5p were attenuated in A549-cell-derived exosomes compared to BEAS-2B-cell-derived exosomes. The analysis of miRNA expression level in BEAS-2B cells indicated that incubation with A549-cell-derived exosomes reduced the expression levels of let-7c-5p and miR-181b-5p. In transient transfections assay, we found that downregulation of let-7c-5p and miR-181b-5p simultaneously showed stronger promotion of BEAS-2B cells migration and invasion than individually. Moreover, exosomes secreted from A549 cells with upregulated expression of let-7c-5p and miR-181b-5p significantly reduce their regulatory effect on BEAS-2B cells. Bioinformatics analyses revealed that let-7c-5p and miR-181b-5p inhibit the EMT process mainly by regulating focal adhesion and mitogen-activated protein kinase (MAPK) signaling pathway. Thus, our data demonstrated that A549-cell-derived exosomal let-7c-5p and miR-181b-5p could induce migration, invasion, and EMT in BEAS-2B cells, which might be regulated through focal adhesion and MAPK signaling pathway. The expression level of let-7c-5p and miR-181b-5p may show great significance for the early diagnosis of lung cancer.

Fine Particulate Matter Induces Childhood Asthma Attacks via Extracellular Vesicle-Packaged Let-7i-5p-Mediated Modulation of the MAPK Signaling Pathway

Fine particulate matter less than 2.5 µm in diameter (PM2.5 ) is a major risk factor for acute asthma attacks in children. However, the biological mechanism underlying this association remains unclear. In the present study, PM2.5 -treated HBE cells-secreted extracellular vesicles (PM2.5 -EVs) caused cytotoxicity in "horizontal" HBE cells and increased the contractility of "longitudinal" sensitive human bronchial smooth muscle cells (HBSMCs). RNA sequencing showed that let-7i-5p is significantly overexpressed in PM2.5 -EVs and asthmatic plasma; additionally, its level is correlated with PM2.5 exposure in children with asthma. The combination of EV-packaged let-7i-5p and the traditional clinical biomarker IgE exhibits the best diagnostic performance (area under the curve [AUC] = 0.855, 95% CI = 0.786-0.923). Mechanistically, let-7i-5p is packaged into PM2.5 -EVs by interacting with ELAVL1 and internalized by both "horizontal" recipient HBE cells and "longitudinal" recipient-sensitive HBSMCs, with subsequent activation of the MAPK signaling pathway via suppression of its target DUSP1. Furthermore, an injection of EV-packaged let-7i-5p into PM2.5 -treated juvenile mice aggravated asthma symptoms. This comprehensive study deciphered the remodeling of the extracellular environment mediated by the secretion of let-7i-5p-enriched EVs during PM2.5 -induced asthma attacks and identified plasma EV-packaged let-7i-5p as a novel predictor of childhood asthma.

Exosomal miR-101-3p and miR-423-5p inhibit medulloblastoma tumorigenesis through targeting FOXP4 and EZH2

Exosomal microRNAs (miRNAs) have been implicated in the development and progression of a variety of tumors; however, whether they contribute to medulloblastoma (MB) tumorigenesis remains to be elucidated. To address this, we first characterized the miRNA profiles of circulating exosomes by miRNA sequencing to identify miRNAs differentially expressed between children with MB and healthy controls. Then, we conducted in vitro and in vivo functional assays with the identified miRNAs and their predicted targets. We found that, compared with healthy controls, 35 miRNAs were upregulated and 5 downregulated in exosomes isolated from the plasma of MB patients. We further found that the expression of miR-101-3p and miR-423-5p was significantly higher in plasma exosomes from MB patients than in healthy controls in an expanded cohort and these exosomal miRNAs could be delivered to tumor cells via exosomes. An in vitro functional analysis of miR-101-3p and miR-423-5p showed that treating MB cells with the corresponding mimics significantly inhibited the proliferation, colony-forming ability, migratory ability, and invasive capacity of tumor cells, and promoted cell apoptosis. Additionally, miR-101-3p and miR-423-5p were found to act as tumor suppressors by directly targeting a common gene, FOXP4, which encodes a transcription factor with a vital role in embryonic development and tumorigenesis. Moreover, miR-101-3p also targeted EZH2, a histone methyltransferase, to reinforce its tumor inhibitory effects. Using a xenograft nude mouse model of MB, we further identified that the overexpression of miR-101-3p and miR-423-5p inhibited tumorigenesis in vivo. Our findings provide novel insights into the functions of exosomal miRNAs in mediating MB progression and suggest a potential therapeutic approach for the treatment of children with MB.

New Insights Into the Regulatory Roles of Extracellular Vesicles in Tumor Angiogenesis and Their Clinical Implications

Angiogenesis is required for tumor growth and development. Extracellular vesicles (EVs) are important signaling entities that mediate communication between diverse types of cells and regulate various cell biological processes, including angiogenesis. Recently, emerging evidence has suggested that tumor-derived EVs play essential roles in tumor progression by regulating angiogenesis. Thousands of molecules are carried by EVs, and the two major types of biomolecules, noncoding RNAs (ncRNAs) and proteins, are transported between cells and regulate physiological and pathological functions in recipient cells. Understanding the regulation of EVs and their cargoes in tumor angiogenesis has become increasingly important. In this review, we summarize the effects of tumor-derived EVs and their cargoes, especially ncRNAs and proteins, on tumor angiogenesis and their mechanisms, and we highlight the clinical implications of EVs in bodily fluids as biomarkers and as diagnostic, prognostic, and therapeutic targets in cancer patients.

Exosomes in Cardiovascular Diseases: Pathological Potential of Nano-Messenger

Cardiovascular diseases (CVDs) represent a major global health problem, due to their continued high incidences and mortality. The last few decades have witnessed new advances in clinical research which led to increased survival and recovery in CVD patients. Nevertheless, elusive and multifactorial pathophysiological mechanisms of CVD development perplexed researchers in identifying efficacious therapeutic interventions. Search for novel and effective strategies for diagnosis, prevention, and intervention for CVD has shifted research focus on extracellular vesicles (EVs) in recent years. By transporting molecular cargo from donor to recipient cells, EVs modulate gene expression and influence the phenotype of recipient cells, thus EVs prove to be an imperative component of intercellular signaling. Elucidation of the role of EVs in intercellular communications under physiological conditions implied the enormous potential of EVs in monitoring and treatment of CVD. The EVs secreted from the myriad of cells in the cardiovascular system such as cardiomyocytes, cardiac fibroblasts, cardiac progenitor cells, endothelial cells, inflammatory cells may facilitate the communication in physiological and pathological conditions. Understanding EVs-mediated cellular communication may delineate the mechanism of origin and progression of cardiovascular diseases. The current review summarizes exosome-mediated paracrine signaling leading to cardiovascular disease. The mechanistic role of exosomes in cardiovascular disease will provide novel avenues in designing diagnosis and therapeutic interventions.

Strategies for Engineering Exosomes and Their Applications in Drug Delivery

Exosomes are representative of a promising vehicle for delivery of biomolecules. Despite their discovery nearly 40 years, knowledge of exosomes and extracellular vesicles (EVs) and the role they play in etiology of disease and normal cellular physiology remains in its infancy. EVs are produced in almost all cells, containing nucleic acids, lipids, and proteins delivered from donor cells to recipient cells. Consequently, they act as mediators of intercellular communication and molecular transfer. Recent studies have shown that, exosomes are associated with numerous physiological and pathological processes as a small subset of EVs, and they play a significant role in disease progression and treatment. In this review, we discuss several key questions: what are exosomes, why do they matter, and how do we repurpose them in their strategies and applications in drug delivery systems. In addition, opportunities and challenges of exosome-based theranostics are also described and directions for future research are presented.

Extracellular Vesicles in Lung Cancer Metastasis and Their Clinical Applications

Extracellular vesicles (EVs) are heterogenous membrane-encapsulated vesicles secreted by every cell into the extracellular environment. EVs carry bioactive molecules, including proteins, lipids, DNA, and different RNA forms, which can be internalized by recipient cells, thus altering their biological characteristics. Given that EVs are commonly found in most body fluids, they have been widely described as mediators of communication in several physiological and pathological processes, including cancer. Moreover, their easy detection in biofluids makes them potentially useful candidates as tumor biomarkers. In this manuscript, we review the current knowledge regarding EVs and non-coding RNAs and their role as drivers of the metastatic process in lung cancer. Furthermore, we present the most recent applications for EVs and non-coding RNAs as cancer therapeutics and their relevance as clinical biomarkers.

Roles and mechanisms of exosomal non-coding RNAs in human health and diseases

Exosomes play a role as mediators of cell-to-cell communication, thus exhibiting pleiotropic activities to homeostasis regulation. Exosomal non-coding RNAs (ncRNAs), mainly microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), are closely related to a variety of biological and functional aspects of human health. When the exosomal ncRNAs undergo tissue-specific changes due to diverse internal or external disorders, they can cause tissue dysfunction, aging, and diseases. In this review, we comprehensively discuss the underlying regulatory mechanisms of exosomes in human diseases. In addition, we explore the current knowledge on the roles of exosomal miRNAs, lncRNAs, and circRNAs in human health and diseases, including cancers, metabolic diseases, neurodegenerative diseases, cardiovascular diseases, autoimmune diseases, and infectious diseases, to determine their potential implication in biomarker identification and therapeutic exploration.

Non-coding RNAs in Regulating Tumor Angiogenesis

Non-coding RNAs (ncRNAs) are RNAs that do not encode proteins, but perform biological functions in various physiological and pathological processes, including cancer formation, inflammation, and neurological diseases. Tumor blood vessels are a key target for cancer management. A number of factors regulate the angiogenesis of malignant tumors. NcRNAs participate in the regulation of tumor angiogenesis. Abnormal expression of ncRNAs act as tumor suppressors or oncogenes to affect the development of tumors. In this review we summarized the biological functions of ncRNAs, and discussed its regulatory mechanisms in tumor angiogenesis. This article will provide new insights for the research of ncRNAs in tumor angiogenesis.

The role of microRNA-21 in the onset and progression of cancer

MicroRNAs (miRNAs), a class of small noncoding RNA, posttranscriptionally regulate the expression of genes. Aberrant expression of miRNA is reported in various types of cancer. Since the first report of oncomiR-21 involvement in the glioma, its upregulation was reported in multiple cancers and was allied with high oncogenic property. In addition to the downregulation of tumor suppressor genes, the miR-21 is also associated with cancer resistance to various chemotherapy. The recent research is appraising miR-21 as a promising cancer target and biomarker for early cancer detection. In this review, we briefly explain the biogenesis and regulation of miR-21 in cancer cells. Additionally, the review features the assorted genes/pathways regulated by the miR-21 in various cancer and cancer stem cells.

Extracellular Vesicles and Cancer Stem Cells in Tumor Progression: New Therapeutic Perspectives

Tumor burden is a complex microenvironment where different cell populations coexist and have intense cross-talk. Among them, a heterogeneous population of tumor cells with staminal features are grouped under the definition of cancer stem cells (CSCs). CSCs are also considered responsible for tumor progression, drug resistance, and disease relapse. Furthermore, CSCs secrete a wide variety of extracellular vesicles (EVs) with different cargos, including proteins, lipids, ssDNA, dsDNA, mRNA, siRNA, or miRNA. EVs are internalized by other cells, orienting the microenvironment toward a protumorigenic and prometastatic one. Given their importance in tumor growth and metastasis, EVs could be exploited as a new therapeutic target. The inhibition of biogenesis, release, or uptake of EVs could represent an efficacious strategy to impair the cross-talk between CSCs and other cells present in the tumor microenvironment. Moreover, natural or synthetic EVs could represent suitable carriers for drugs or bioactive molecules to target specific cell populations, including CSCs. This review will discuss the role of CSCs and EVs in tumor growth, progression, and metastasis and how they affect drug resistance and disease relapse. Furthermore, we will analyze the potential role of EVs as a target or vehicle of new therapies.

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.

Tumor-associated exosomes promote lung cancer metastasis through multiple mechanisms

As an important medium of intercellular communication, exosomes play an important role in information transmission between tumor cells and their microenvironment. Tumor metastasis is a serious influencing factor for poor treatment effect and shortened survival. Lung cancer is a major malignant tumor that seriously threatens human health. The study of the underlying mechanisms of exosomes in tumor genesis and development may provide new ideas for early and effective diagnosis and treatment of lung cancer metastasis. Many studies have shown that tumor-derived exosomes promote lung cancer development through a number of processes. By promoting epithelial-mesenchymal transition of tumor cells, they induce angiogenesis, establishment of the pretransfer microenvironment, and immune escape. This understanding enables researchers to better understand the mechanism of lung cancer metastasis and explore new treatments for clinical application. In this article, we systematically review current research progress of tumor-derived exosomes in metastasis of lung cancer. Although positive progress has been made toward understanding the mechanism of exosomes in lung cancer metastasis, systematic basic research and clinical translational research remains lacking and are needed to translate our scientific understanding toward applications in the clinical diagnosis and treatment of lung cancer metastasis in the near future.

Exosomes in Lung Cancer: Actors and Heralds of Tumor Development

Lung cancer is a leading cause of cancer-related death worldwide and in most cases, diagnosis is reached when the tumor has already spread and prognosis is quite poor. For that reason, the research for new biomarkers that could improve early diagnosis and its management is essential. Exosomes are microvesicles actively secreted by cells, especially by tumor cells, hauling molecules that mimic molecules of the producing cells. There are multiple methods for exosome isolation and analysis, although not standardized, and cancer exosomes from biological fluids are especially difficult to study. Exosomes' cargo proteins, RNA, and DNA participate in the communication between cells, favoring lung cancer development by delivering signals for growth, metastasis, epithelial mesenchymal transition, angiogenesis, immunosuppression and even drug resistance. Exosome analysis can be useful as a type of liquid biopsy in the diagnosis, prognosis and follow-up of lung cancer. In this review, we will discuss recent advances in the role of exosomes in lung cancer and their utility as liquid biopsy, with special attention to isolating methods.

MicroRNAs Patterns as Potential Tools for Diagnostic and Prognostic Follow-Up in Cancer Survivorship

Advances in screening methods and pharmacological treatments are increasing the life expectancy of cancer patients. During recent decades, the community of long-term disease-free cancer survivors (LCS) has grown exponentially, raising the issues related to cancer follow-up. Cancer relapse and other cancer-related diseases, as well as lifestyle, influence cancer survival. Recently, the regulatory role of microRNAs (miRNAs) in gene expression and their involvement in human diseases, including cancer, has been identified. Extracellular circulating miRNAs (ECmiRNAs) have been found in biological fluids and specific ECmiRNAs have been associated with cancer development and progression or with a therapy response. Here, we focus on the pivotal role of ECmiRNAs as biomarkers in cancer diagnosis and prognosis. Then, we discuss the relevance of ECmiRNAs expression in cancer survivors for the identification of specific ECmiRNAs profiles as potential tools to assess cancer outcome and to control LCS follow-up.

Tumor-derived exosomes: Nanovesicles made by cancer cells to promote cancer metastasis

Nanomedicine usually refers to nanoparticles that deliver the functional drugs and siRNAs to treat cancer. Recent research has suggested that cancer cells can also make nanoparticles that also deliver functional molecules in promoting cancer metastasis, which is the leading cause of various cancer mortalities. This nanoparticle is called tumor-derived vesicles, or better-known as tumor-derived exosomes (TEXs). TEXs are nanoscale membrane vesicles (30-140 nm) that are released continuously by various types of cancer cells and contain tumor-derived functional biomolecules, including lipids, proteins, and genetic molecules. These endogenous TEXs can interact with host immune cells and epithelial cells locally and systemically. More importantly, they can reprogram the recipient cells in favor of promoting metastasis through facilitating tumor cell local invasion, intravasation, immune evasion, extravasation, and survival and growth in distant organs. Growing evidence suggests that TEXs play a key role in cancer metastasis. Here, we will review the most recent findings of how cancer cells harness TEXs to promote cancer metastasis through modulating vascular permeability, suppressing systemic immune surveillance, and creating metastatic niches. We will also summarize recent research in targeting TEXs to treat cancer metastasis.

RETRACTED: Pancreatic cancer cells-derived exosomal long non-coding RNA CCAT1/microRNA-138-5p/HMGA1 axis promotes tumor angiogenesis

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Concern was raised about the reliability of the Western blot results in Figs. 2B and 5I+J, which appear to have the same eyebrow shaped phenotype as many other publications tabulated here (https://docs.google.com/spreadsheets/d/149EjFXVxpwkBXYJOnOHb6RhAqT4a2llhj9LM60MBffM/edit#gid=0). In addition, Fig. 4B appears to show a digital composition of xenografted tumors. The journal requested the corresponding author comment on these concerns and provide the raw data. However the authors were not able to satisfactorily fulfil this request and therefore the Editor-in-Chief decided to retract the article.

Exosomes in the lung cancer microenvironment: biological functions and potential use as clinical biomarkers

Lung cancer is one of the most common malignant tumours worldwide. however, emerging immunotherapy and targeted therapies continue to show limited efficacy. In the search for new targets for lung cancer treatment, exosomes have become a major focus of research. Exosomes play an important role in the tumour microenvironment (TME) of lung cancer and affect invasion, metastasis, and treatment responses. This review describes our current understanding of the release of exosomes derived from different cells in the TME, the effects of exosomes on T/Tregs, myeloid-derived suppressor cells, tumour-associated macrophages, dendritic cells, and natural killer cells, and the role of exosomes in the endothelial–mesenchymal transition, angiogenesis, and cancer-associated fibroblasts. In particular, this review focuses on the potential clinical applications of exosomes in the lung cancer microenvironment and their prognostic and diagnostic value.

MicroRNAs: emerging driver of cancer perineural invasion

The perineural invasion (PNI), which refers to tumor cells encroaching on nerve, is a clinical feature frequently occurred in various malignant tumors, and responsible for postoperative recurrence, metastasis and decreased survival. The pathogenesis of PNI switches from 'low-resistance channel' hypothesis to 'mutual attraction' theory between peripheral nerves and tumor cells in perineural niche. Among various molecules in perineural niche, microRNA (miRNA) as an emerging modulator of PNI through generating RNA-induced silencing complex (RISC) to orchestrate oncogene and anti-oncogene has aroused a wide attention. This article systematically reviewed the role of microRNA in PNI, promising to identify new biomarkers and offer cancer therapeutic targets.

The roles of tumor-derived exosomes in altered differentiation, maturation and function of dendritic cells

Tumor-derived exosomes (TDEs) have been shown to impede anti-tumor immune responses via their immunosuppressive cargo. Since dendritic cells (DCs) are the key mediators of priming and maintenance of T cell-mediated responses; thus it is logical that the exosomes released by tumor cells can exert a dominant influence on DCs biology. This paper intends to provide a mechanistic insight into the TDEs-mediated DCs abnormalities in the tumor context. More importantly, we discuss extensively how tumor exosomes induce subversion of DCs differentiation, maturation and function in separate sections. We also briefly describe the importance of TDEs at therapeutic level to help guide future treatment options, in particular DC-based vaccination strategy, and review advances in the design and discovery of exosome inhibitors. Understanding the exosomal content and the pathways by which TDEs are responsible for immune evasion may help to revise treatment rationales and devise novel therapeutic approaches to overcome the hurdles in cancer treatment.

Exosomal microRNAs in non-small cell lung cancer

Lung cancer is one of the highest incidence cancer types worldwide and one with the lowest 5-year survival rate of all cancer types. Despite recent insights into lung cancer pathobiology, including novel biomarker-targeted therapies and immunotherapies, most of lung patients are diagnosed at late stages with limited and ineffective treatments. Therefore, more approaches are needed to eradicate lung cancer. In the last years, small extracellular vesicles (EVs) secreted by tumor cells have been gaining relevance. These intercellular signal mediators, called exosomes, contain a huge range of biological elements, including lipids, nucleic acids and miRNAs, among others, that carry relevant information. The role of exosomes in cancer progression is dependent on cancer type, molecular characteristics and stage. MicroRNAs molecules are a big part of the content of exosomes cargo and probably the most studied ones. Due to the regulatory role in gene expression, miRNAs may provide information of the molecular characteristics of the tumor and be also able to reprogram distant target cells. Exosomal miRNAs can modulate different biological processes in cancer such as growth, progression, invasion, angiogenesis, metastasis and drug resistance; playing a critical role in modifying the microenvironment of non-small cell lung cancer (NSCLC). Therefore, they can act by regulating tumor resistance and also be useful to monitoring the response/relapse to targeted therapies. In this work, we summarize the relevant advances on the potential role of exosomal miRNAs in NSCLC pathobiogenesis, highlighting the clinical utility of exosomal microRNAs as biomarkers for the NSCLC diagnosis, prognosis, drug resistance and therapeutic strategies.

Mesenchymal stem cell-derived exosomes containing miR-145-5p reduce inflammation in spinal cord injury by regulating the TLR4/NF-κB signaling pathway

EXs (Exosomes) secreted by mesenchymal stem cells (MSCs) have the potential to treat spinal cord injury (SCI), this study aimed to further explore the therapeutic effect of EXs on SCI. Firstly, EXs were extracted from MSCs and analyzed with a transmission electron microscope. Next, MSCs with or without the miR-145-5p plasmid were injected into the SCI rat model, and then rat damage was evaluated by BBB score, HE staining and Nissl staining. And then Luciferase experiment verified the targeting relationship between miR-145-5p and TLR4. Furthermore, LPS-induced PC12 cells were established and incubated with Dil-labeled MSC-EXs to explore their effects on cell viability, apoptosis and inflammation through MTT, flow cytometry and ELISA, respectively. In addition, expressions of TLR4/NF-κB signaling pathway related factors were measured by qRT-PCR and Western blot. The results showed that after MSCs were successfully isolated, the existence of EXs in MSCs was confirmed. Moreover, MSC-EXs containing miR-145-5p improved functional recovery and reduced histopathological injury and inflammation in SCI rats. And MSC-EXs promoted miR-145-5p expression in spinal cord tissue and inhibited TLR4/NF-κB pathway activation in SCI rats. MSC-EXs inhibited LPS-induced inflammatory response and activation of the TLR4/NF-κB pathway in PC12 cells. In addition, we also found that miR-145-5p specifically targeted TLR4. TLR4 overexpression significantly reversed the effect of EX-miR-145-5p on maintaining PC12 cell viability, inhibiting apoptosis and inflammatory response, and activating TLR4/NF- κB pathway. In conclusion, mesenchymal stem cell-derived EXs containing miR-145-5p reduce inflammation in spinal cord injury by regulating the TLR4/NF-κB signaling pathway.

Epigenetic regulation of angiogenesis in lung cancer

Lung cancer is the leading cause of cancer-related deaths worldwide, in which angiogenesis is highly required for lung cancer cell growth and metastasis. Genetic regulation of this multistep process is being studied extensively, however, relatively less is known about the epigenetic regulation of angiogenesis in lung cancer. Several epigenetic alterations contribute to regulating angiogenesis, such as epimodifications of DNA, posttranslational modification of histones, and expression of noncoding RNAs. Here, we review the current knowledge of the epigenetic regulation of angiogenesis and discuss the potential clinical applications of epigenetic-based anticancer therapy in lung cancer. Overall, epigenetic-based therapy will likely emerge as a prominent approach to treat lung cancer in the future.

Extracellular Vesicle Mediated Vascular Pathology in Glioblastoma

Glioblastoma (GBM) is an incurable, infiltrative high-grade brain tumour associated with dramatic vascular responses observed both locally (angiogenesis, vascular cooption, angiocrine effects, microthrombosis) and systemically (venous thromboembolism). GBM-associated vascular pathology is diagnostically relevant and constitutes a source of morbidity, mortality and progressive changes in tumour biology. Extracellular vesicles (EVs) have emerged as unique mediators of vascular effects in brain tumours acting as vehicles for intercellular transfer of oncoproteins (e.g. EGFRvIII), RNA, DNA and molecular effectors of angiogenesis and thrombosis. Vascular effects of GBM EVs are regulated by cancer cell genome, epigenome and microenvironment and differ between subtypes of cancer cells and stem cells. Understanding and targeting EV-driven vascular processes in GBM may offer new approaches to diagnose and treat these intractable tumours.

The roles of small extracellular vesicles in lung cancer: Molecular pathology, mechanisms, diagnostics, and therapeutics

Small extracellular vesicles (sEVs) are submicron-sized, lipid-bilayer-enclosed particles that are released from cells. A variety of tissue-specific molecules, including proteins, DNA fragments, RNA, lipids, and metabolites, can be selectively encapsulated into sEVs and delivered to nearby and distant recipient cells. Incontestable and growing evidence shows the important biological roles and the clinical relevance of sEVs in tumors. In particular, recent studies validate sEVs can be used for early tumor diagnostics, staging, and treatment monitoring. Moreover, sEVs have been used as drug delivery nanocarriers, cancer vaccines, and antigen conferrers. While still in its infancy, the field of sEV-based fundamental and translational studies has been rapidly advancing. This review comprehensively examines the latest sEV-related studies in lung cancers, encompassing extracellular vesicles and their roles in lung cancer pathophysiology, diagnostics, and therapeutics. The state-of-the-art technologies for sEV isolation, downstream molecular analyses, and sEV-based therapies indicate their potency as tools for understanding the pathology and promising clinical management of lung cancers.

A meta-analysis on the relationship of exosomes and the prognosis of lung cancer

BACKGROUND

A lot of research evidence shows that exosomes play an indelible role in the prognosis of lung cancer, but there are many disputes. Therefore, we conduct a meta-analysis to further demonstrate.

METHODS

A literature retrieval was performed through a search of PubMed, Embase, Web of Science, Cochrane, CKNI, Wanfang, and other databases to locate documents from the literature that satisfied the inclusion criteria. There were four outcome indicators: overall survival (OS), disease-free survival (DFS), disease-specific survival (DSS), and progression-free survival (PFS). Subgroup analysis was conducted according to sample size, country, detection method, analysis method, and pathological type. Stata 14.0 software was used to evaluate the prognostic value of exosomes in lung cancer.

RESULTS

A total of 2456 patients with lung cancer from 29 studies in 16 articles were included. The expression level of exosomes was closely associated with the OS and DFS of patients, although no statistical difference was observed between exosomes and DSS or PFS. Eighteen studies with 2,110 patients were evaluated to examine the prognostic value of exosomes in lung cancer by exploring the association between exosomes and OS. The results showed that exosomes were strongly associated with worse OS, and the combined hazard ratio (HR) was 2.01 (95% confidence interval [CI]: 1.70-2.39, P = .000). Six studies investigated the association between exosomes and DFS, and showed a pooled HR of 2.48 (95% CI: 1.75-3.53, P = .000).

CONCLUSION

Our analysis indicated that the expression level of exosomes was closely associated with the OS and DFS of patients with lung cancer, suggesting that exosomes are associated with poor prognosis of lung cancer. Exosomes may be a new biomarker for the prognosis of lung cancer, although a large number of prospective studies are still needed to support this.

The role of extracellular vesicles and PD-L1 in glioblastoma-mediated immunosuppressive monocyte induction

BACKGROUND

Immunosuppression in glioblastoma (GBM) is an obstacle to effective immunotherapy. GBM-derived immunosuppressive monocytes are central to this. Programmed cell death ligand 1 (PD-L1) is an immune checkpoint molecule, expressed by GBM cells and GBM extracellular vesicles (EVs). We sought to determine the role of EV-associated PD-L1 in the formation of immunosuppressive monocytes.

METHODS

Monocytes collected from healthy donors were conditioned with GBM-derived EVs to induce the formation of immunosuppressive monocytes, which were quantified via flow cytometry. Donor-matched T cells were subsequently co-cultured with EV-conditioned monocytes in order to assess effects on T-cell proliferation. PD-L1 constitutive overexpression or short hairpin RNA-mediated knockdown was used to determined the role of altered PD-L1 expression.

RESULTS

GBM EVs interact with both T cells and monocytes but do not directly inhibit T-cell activation. However, GBM EVs induce immunosuppressive monocytes, including myeloid-derived suppressor cells (MDSCs) and nonclassical monocytes (NCMs). MDSCs and NCMs inhibit T-cell proliferation in vitro and are found within GBM in situ. EV PD-L1 expression induces NCMs but not MDSCs, and does not affect EV-conditioned monocytes T-cell inhibition.

CONCLUSION

These findings indicate that GBM EV-mediated immunosuppression occurs through induction of immunosuppressive monocytes rather than direct T-cell inhibition and that, while PD-L1 expression is important for the induction of specific immunosuppressive monocyte populations, immunosuppressive signaling mechanisms through EVs are complex and not limited to PD-L1.

Exosomal MicroRNAs Mediating Crosstalk Between Cancer Cells With Cancer-Associated Fibroblasts and Tumor-Associated Macrophages in the Tumor Microenvironment

Exosomes are small extracellular vesicles containing diverse bioactive molecules. They play essential roles in mediating bidirectional interplay between cancer and stromal cells. Specific elements are selected into different types of exosomes via various mechanisms, including microRNAs (miRNAs), a subset of non-coding RNA that could epigenetically reprogram cells and modulate their activities. Cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAMs) are two major types of stromal cells inhibiting immune response and facilitating tumor progression. Notably, accumulated studies provided critical evidence regarding the significance of exosomal miRNA–mediated intercellular crosstalk between cancer cells with TAMs and CAFs for tumor progression. This review aimed to summarize the current knowledge of cell–cell interactions between stromal and cancer cells conveyed by exosome-derived miRNAs. The findings might help find effective therapeutic targets of cancer.

Study of NSCLC cell migration promoted by NSCLC-derived extracellular vesicle using atomic force microscopy

Extracellular vesicles (EVs) secreted by cancer cells play a key role in the cancer microenvironment and progression. Previous studies have mainly focused on molecular functions, cellular components and biological processes using chemical and biological methods. However, whether the mechanical properties of cancer cells change due to EVs remains poorly understood. This work studies the effects of mechanical changes in non-small cell lung cancer (NSCLC) cells after treatment with EVs on migration by atomic force microscopy (AFM). Different concentrations of EVs were added into the experimental groups based on co-culture experiments, while the control group was cultured without EVs for 48 h. Cellular migration was evaluated by wound healing experiments. The cellular morphology, cell stiffness and surface adhesion were investigated by AFM. Cytoskeleton changes were detected by fluorescence staining assay. By comparison to the control group, the cell migration was enhanced. After treatment with EVs, the cell length and height show an upward trend, and the adhesion force and Young's modulus show a downward trend, and filopodia were also detected in the cells. Overall, the EVs promoted the migration of NSCLC cells by regulating cells' physical properties and skeletal rearrangement.

Extracellular vesicles from human airway basal cells respond to cigarette smoke extract and affect vascular endothelial cells

The human airway epithelium lining the bronchial tree contains basal cells that proliferate, differentiate, and communicate with other components of their microenvironment. One method that cells use for intercellular communication involves the secretion of exosomes and other extracellular vesicles (EVs). We isolated exosome-enriched EVs that were produced from an immortalized human airway basal cell line (BCi-NS1.1) and found that their secretion is increased by exposure to cigarette smoke extract, suggesting that this stress stimulates release of EVs which could affect signaling to other cells. We have previously shown that primary human airway basal cells secrete vascular endothelial growth factor A (VEGFA) which can activate MAPK signaling cascades in endothelial cells via VEGF receptor-2 (VEGFR2). Here, we show that exposure of endothelial cells to exosome-enriched airway basal cell EVs promotes the survival of these cells and that this effect also involves VEGFR2 activation and is, at least in part, mediated by VEGFA present in the EVs. These observations demonstrate that EVs are involved in the intercellular signaling between airway basal cells and the endothelium which we previously reported. The downstream signaling pathways involved may be distinct and specific to the EVs, however, as increased phosphorylation of Akt, STAT3, p44/42 MAPK, and p38 MAPK was not seen following exposure of endothelial cells to airway basal cell EVs.

The Causes and Consequences of miR-503 Dysregulation and Its Impact on Cardiovascular Disease and Cancer

microRNAs (miRs) are short, non-coding RNAs that regulate gene expression by mRNA degradation or translational repression. Accumulated studies have demonstrated that miRs participate in various biological processes including cell differentiation, proliferation, apoptosis, metabolism and development, and the dysregulation of miRs expression are involved in different human diseases, such as neurological, cardiovascular disease and cancer. microRNA-503 (miR-503), one member of miR-16 family, has been studied widely in cardiovascular disease and cancer. In this review, we summarize and discuss the studies of miR-503 in vitro and in vivo, and how miR-503 regulates gene expression from different aspects of pathological processes of diseases, including carcinogenesis, angiogenesis, tissue fibrosis and oxidative stress; We will also discuss the mechanisms of dysregulation of miR-503, and whether miR-503 could be applied as a diagnostic marker or therapeutic target in cardiovascular disease or cancer.

METTL3-mediated m6A modification of ZBTB4 mRNA is involved in the smoking-induced EMT in cancer of the lung

N6-methyladenosine (m6A) is an epigenetic modification associated with various tumors, but its role in tumorigenesis remains unexplored. Here, as confirmed by methylated RNA immunoprecipitation sequencing (meRIP-seq) and RNA sequencing (RNA-seq) analyses, exposure of human bronchial epithelial (HBE) cells to cigarette smoke extract (CSE) caused an m6A modification in the 3' UTR of ZBTB4, a transcriptional repressor. For these cells, CSE also elevated methyltransferase-like 3 (METTL3) levels, which increased the m6A modification of ZBTB4. RIP-qPCR illustrated that ZBTB4 was the intent gene of YTHDF2 and that levels of ZBTB4 were decreased in an YTHDF2-dependent mechanism. The lower levels of ZBTB4 were associated with upregulation of EZH2, which enhanced H3K27me3 combining with E-cadherin promoter, causing lower E-cadherin levels and induction of the epithelial-mesenchymal transition (EMT). Further, in the lungs of mice, downregulation of METTL3 alleviated the cigarette smoke (CS)-induced EMT. Further, the expression of METTL3 was high in the lung tissues of smokers and inversely correlated with ZBTB4. Overall, our results show that the METTL3-mediated m6A modification of ZBTB4 via EZH2 is involved in the CS-induced EMT and in lung cancer. These results indicate that m6A modifications are a potential therapeutic target of lung damage induced by CS.

Circulating MicroRNAs in Blood and Other Body Fluids as Biomarkers for Diagnosis, Prognosis, and Therapy Response in Lung Cancer

The identification of circulating microRNAs (miRNAs) in peripheral blood and other body fluids has led to considerable research interest in investigating their potential clinical application as non-invasive biomarkers of cancer, including lung cancer, the deadliest malignancy worldwide. Several studies have found that alterations in the levels of miRNAs in circulation are able to discriminate lung cancer patients from healthy individuals (diagnosis) and are associated with patient outcome (prognosis) and treatment response (prediction). Increasing evidence indicates that circulating miRNAs may function as mediators of cell-to-cell communication, affecting biological processes associated with tumor initiation and progression. This review is focused on the most recent studies that provide evidence of the potential value of circulating miRNAs in blood and other body fluids as non-invasive biomarkers of lung cancer in terms of diagnosis, prognosis, and response to treatment. The status of their potential clinical application in lung cancer is also discussed, and relevant clinical trials were sought and are described. Because of the relevance of their biological characteristics and potential value as biomarkers, this review provides an overview of the canonical biogenesis, release mechanisms, and biological role of miRNAs in lung cancer.

Diagnostic and Therapeutic Applications of Exosome Nanovesicles in Lung Cancer: State-of-The-Art

Lung cancer is a malignant disease with a frequency of various morbidity, mortality, and poor prognosis in patients that the conventional therapeutic approaches are not efficient sufficiently. Recently, with the discovery of exosomes, researchers have examined new approaches in the development, diagnosis, treatment, and drug delivery of various cancer, such as lung cancer, and display various its potential. Investigation of exosome-derived lung cancer cells contents and preparation of their exhaustive profile by advanced technics such as labeling exosome with nanoparticle and types of mass spectroscopy methods will assist researchers for take advantage of the specific properties of exosomes. Moreover, scientists will present encouraging ways for the treatment of lung cancer with loaded of drugs, proteins, microRNA, and siRNA in specific antigen targeted exosomes. This manuscript will include brief details on the role of exosomes as a novel prognostic biomarker (by the content of lipid, surface and internal protein, miRNAs, and LnRNAs) and therapeutic agent (as vaccine and targeted drug delivery) in lung cancer.

Extracellular vesicle-mediated regulation of tumor angiogenesis- implications for anti-angiogenesis therapy

Angiogenesis plays an important role in tumour progression. However, anti‐angiogenesis therapy of inhibiting pro‐angiogenic factors failed to meet expectations in certain types of tumour in clinical trials. Recent studies reveal that tumour‐derived extracellular vesicles (EVs) are essential in tumour angiogenesis and anti‐angiogenesis drug resistance. This function has most commonly been attributed to EV contents including proteins and non‐coding RNAs. Here, we summarize the recent findings of tumour‐derived EV contents associated with regulating angiogenesis and illustrate the underlying mechanisms. In addition, the roles of EVs in tumour microenvironmental cells are also illustrated with a focus on how EVs participate in cell‐cell communication, contributing to tumour‐mediated angiogenesis. It will help offer new perspectives on developing targets of anti‐angiogenesis drugs and improve the efficacy of anti‐angiogenesis therapies based on tumour‐derived EVs.

Exosomes and Lung Cancer: Roles in Pathophysiology, Diagnosis and Therapeutic Applications

Lung cancer is a malignancy with a high morbidity and mortality rate, and affected patients have low survival and poor prognosis. The therapeutic approaches for the treatment of this cancer, including radiotherapy and chemotherapy, are not particularly effective partly due to late diagnosis. Therefore, the search for new diagnostic and prognostic tools is a critical issue. Novel biomarkers, such as exosomes, could be considered as potential diagnostic tools for malignancies, particularly lung cancer. Exosomes are nanovesicles, which are associated with different physiological and pathological conditions. It has been shown that these particles are released from many cells, such as cancer cells, immune cells and to some degree normal cells. Exosomes could alter the behavior of target cells through intercellular transfer of their cargo (e.g. DNA, mRNA, long non-coding RNAs, microRNAs and proteins). Thus, these vehicles may play pivotal roles in various physiological and pathological conditions. The current insights into lung cancer pathogenesis suggest that exosomes are key players in the pathogenesis of this cancer. Hence, these nanovesicles and their cargos could be used as new diagnostic, prognostic and therapeutic biomarkers in the treatment of lung cancer. Besides the diagnostic roles of exosomes, their use as drug delivery systems and as cancer vaccines is under investigation. The present review summarizes the current information on the diagnostic and pathogenic functions of exosomes in lung cancer.

Role of Exosomal miRNA in Bladder Cancer: A Promising Liquid Biopsy Biomarker

Bladder cancer (BCa) is the most prevalent neoplasia of the urinary tract. Unfortunately, limited improvements in effective BCa management have meant that it remains a challenging disease. Cystoscopy has been the gold standard for BCa diagnosis and surveillance for over two centuries but is an invasive and expensive approach. Recently, liquid biopsy has been identified as a promising field of cancer research, due to its noninvasiveness and ease of sampling. Liquid biopsy samples could provide comprehensive information regarding the genetic landscape of cancer and could track genomic evolution of the disease over time. Exosomes, which contain RNAs, DNAs, and proteins, are a potential source of tumor biomarkers in liquid biopsy samples. In particular, exosomal miRNAs (exomiRs) hold great promise as biomarkers for tumor development and progression. In this review, we provide an overview of liquid biopsy biomarkers, with a particular focus on the use of exomiRs as biomarkers of cancer, and summarize their clinical implications for BCa. Finally, we discuss the future perspectives of these biomarkers in cancer research.

Exosome-derived miR-142-5p remodels lymphatic vessels and induces IDO to promote immune privilege in the tumour microenvironment

Clinical response to immunotherapy is closely associated with the immunosuppressive tumour microenvironment (TME), and influenced by the dynamic interaction between tumour cells and lymphatic endothelial cells (LECs). Here, we show that high levels of miR-142-5p positively correlate with indoleamine 2,3-dioxygenase (IDO) expression in tumour-associated lymphatic vessels in advanced cervical squamous cell carcinoma (CSCC). The miR-142-5p is transferred by CSCC-secreted exosomes into LECs to exhaust CD8+ T cells via the up-regulation of lymphatic IDO expression, which was abrogated by an IDO inhibitor. Mechanistically, miR-142-5p directly down-regulates lymphatic AT-rich interactive domain-containing protein 2 (ARID2) expression, inhibits DNA methyltransferase 1 (DNMT1) recruitment to interferon (IFN)-γ promoter, and enhances IFN-γ transcription by suppressing promoter methylation, thereby leading to elevated IDO activity. Furthermore, increased serum exosomal miR-142-5p levels and the consequent IDO activity positively correlate with CSCC progression. In conclusion, exosomes secreted by CSCC cells deliver miR-142-5p to LECs and induce IDO expression via ARID2-DNMT1-IFN-γ signalling to suppress and exhaust CD8+ T cells. Our study suggests that LECs act as an integral component of the immune checkpoint(s) in the TME and may serve as a potential new target for CSCC diagnosis and treatment.

Progress on pivotal role and application of exosome in lung cancer carcinogenesis, diagnosis, therapy and prognosis

Lung cancer is often diagnosed at an advanced stage and has a poor prognosis. Conventional treatments are not effective for metastatic lung cancer therapy. Although some of molecular targets have been identified with favorable response, those targets cannot be exploited due to the lack of suitable drug carriers. Lung cancer cell-derived exosomes (LCCDEs) receive recent interest in its role in carcinogenesis, diagnosis, therapy, and prognosis of lung cancer due to its biological functions and natural ability to carry donor cell biomolecules. LCCDEs can promote cell proliferation and metastasis, affect angiogenesis, modulate antitumor immune responses during lung cancer carcinogenesis, regulate drug resistance in lung cancer therapy, and be now considered an important component in liquid biopsy assessments for detecting lung cancer. Therapeutic deliverable exosomes are emerging as promising drug delivery agents specifically to tumor high precision medicine because of their natural intercellular communication role, excellent biocompatibility, low immunogenicity, low toxicity, long blood circulation ability, biodegradable characteristics, and their ability to cross various biological barriers. Several studies are currently underway to develop novel diagnostic and prognostic modalities using LCCDEs, and to develop methods of exploiting exosomes for use as efficient drug delivery vehicles. Current status of lung cancer and extensive applicability of LCCDEs are illustrated in this review. The promising data and technologies indicate that the approach on LCCDEs implies the potential application of LCCDEs to clinical management of lung cancer patients.

MicroRNAs: Emerging oncogenic and tumor-suppressive regulators, biomarkers and therapeutic targets in lung cancer

Lung cancer is one of the most common solid tumors worldwide and the leading cause of cancer-related deaths, causing a devastating impact on human health. The clinical prognosis of lung cancer is usually restricted by delayed diagnosis and resistance to anticancer therapies. MicroRNAs, a range of small endogenous noncoding RNAs 22 nucleotides in length, have emerged as one of the most important players in cancer initiation and progression in recent decades. Current evidence reveals pivotal roles of microRNAs in regulating cell proliferation, migration, invasion and metastasis in lung cancer. An increasing number of preclinical and clinical studies have also explored the potential of microRNAs as promising biomarkers and new therapeutic targets for lung cancer. The current review summarizes the most recent progress on the functional mechanisms of microRNAs involved in lung cancer development and progression and further discusses the clinical application of miRNAs as putative therapeutic targets for molecular diagnosis and prognostic prediction in lung cancer.

MicroRNA and ER stress in cancer

The development of biological technologies in genomics, proteomics, and bioinformatics has led to the identification and characterization of the complete set of coding genes and their roles in various cellular pathways in cancer. Nevertheless, the cellular pathways have not been fully figured out like a jigsaw puzzle with missing pieces. The discovery of noncoding RNAs including microRNAs (miRNAs) has provided the missing pieces of the cellular pathways. Likewise, miRNAs have settled many questions of inexplicable patches in the endoplasmic reticulum (ER) stress pathways. The ER stress-caused pathways typified by the unfolded protein response (UPR) are pivotal processes for cellular homeostasis and survival, rectifying uncontrolled proteostasis and determining the cell fate. Although various factors and pathways have been studied and characterized, the understanding of the ER stress requires more wedges to fill the cracks of knowledge about the ER stress pathways. Moreover, the roles of the ER stress and UPR are still controversial in cancer despite their strong potential to promote cancer. The noncoding RNAs, in particular, miRNAs aid in a better understanding of the ER stress and its role in cancer. In this review, miRNAs that are the more-investigated subtype of noncoding RNAs are focused on the interpretation of the ER stress in cancer, following the introduction of miRNA and ER stress.

The Application of Exosomal MicroRNAs in the Treatment of Pancreatic Cancer and Its Research Progress

ABSTRACT

Despite great progress in the treatment of pancreatic cancer under the efforts of researchers, the survival time of patients with pancreatic cancer is shorter than that of patients with other cancers. Thus, we have a great need for innovative therapeutic methods, including research and development of new drugs and innovation of administration methods. Exosomes are a type of extracellular vesicles wrapped by a lipid bilayer. Thanks to the low clearance ratio and strong specificity of exosomes in circulation, together with in-depth research on the surface protein of exosomes and a targeted modification method, there is a strong potential to apply exosomes in the transfer and even targeted delivery of chemotherapeutics, RNA, and natural products. Particularly, exosomes carrying microRNA show good application prospects in cancer therapy. This article is intended to summarize the progress of research relating to the treatment of pancreatic cancer via exosomal microRNAs.

Exosomes: Their Role in Pathogenesis, Diagnosis and Treatment of Diseases

Simple Summary

The aim of this review is to provide an overview of the current scientific evidence concerning the role played by exosomes in the pathogenesis, diagnosis and treatment of diseases. The potential use of exosomes as delivery vectors for small-molecule therapeutic agents will be discussed. In addition, a special emphasis will be placed on the involvement of exosomes in oncological diseases, as well as to their potential therapeutic application as liquid biopsy tools mainly in cancer diagnosis. A better understanding of exosome biology could improve the results of clinical interventions using exosomes as therapeutic agents.

Abstract

Exosomes are lipid bilayer particles released from cells into their surrounding environment. These vesicles are mediators of near and long-distance intercellular communication and affect various aspects of cell biology. In addition to their biological function, they play an increasingly important role both in diagnosis and as therapeutic agents. In this paper, we review recent literature related to the molecular composition of exosomes, paying special attention to their role in pathogenesis, along with their application as biomarkers and as therapeutic tools. In this context, we analyze the potential use of exosomes in biomedicine, as well as the limitations that preclude their wider application.

Progress of exosomes in the diagnosis and treatment of lung cancer

The incidence and mortality of lung cancer account for first place all over the world. Lung cancer lacks early diagnostic biomarkers; lung cancer patients are usually diagnosed in both middle and advanced stages and have poor treatment outcomes. It is more important to find the first diagnostic tools for lung cancer with high specificity and sensitivity. Besides, exosomes are usually nanometer-sized bi-layered lipid vesicles formed and produced by various types of cells. As one of the main modes of intercellular communication, they can deliver multiple functional biomolecules, such as DNA, microRNAs, messenger RNA (mRNA), long non-coding RNA, and proteins, and the events as mentioned above affects different physiological processes of recipient cells. It has been reported that exosomes are involved in different types of cancer, including lung cancer. Various studies proved that exosomes are involved in multiple cancer processes such as cell proliferation, metastasis, epithelial-mesenchymal transition (EMT), angiogenesis, and the tumor microenvironment in lung cancer. Tumor-derived exosomes (TEX) contain a variety of stimulatory and inhibitory factors involved in regulating immune response, which can affect the tumor microenvironment (TME) and thus participate in the formation and progression of lung cancer. This review's primary purpose to review the latest research progress of exosomes in diagnosing and treating lung cancer.