Extracellular vesicles in cancer diagnostics and therapeutics

Shedding Light on Cellular Secrets: A Review of Advanced Optical Biosensing Techniques for Detecting Extracellular Vesicles with a Special Focus on Cancer Diagnosis

In the relentless pursuit of innovative diagnostic tools for cancer, this review illuminates the cutting-edge realm of extracellular vesicles (EVs) and their biomolecular cargo detection through advanced optical biosensing techniques with a primary emphasis on their significance in cancer diagnosis. From the sophisticated domain of nanomaterials to the precision of surface plasmon resonance, we herein examine the diverse universe of optical biosensors, emphasizing their specified applications in cancer diagnosis. Exploring and understanding the details of EVs, we present innovative applications of enhancing and blending signals, going beyond the limits to sharpen our ability to sense and distinguish with greater sensitivity and specificity. Our special focus on cancer diagnosis underscores the transformative potential of optical biosensors in early detection and personalized medicine. This review aims to help guide researchers, clinicians, and enthusiasts into the captivating domain where light meets cellular secrets, creating innovative opportunities in cancer diagnostics.

The role of the hematopoietic stem/progenitor cells-derived extracellular vesicles in hematopoiesis

Hematopoietic stem cells (HSCs) are tightly regulated by specific microenvironments called niches to produce an appropriate number of mature blood cell types. Self-renewal and differentiation are two hallmarks of hematopoietic stem and progenitor cells, and their balance is critical for proper functioning of blood and immune cells throughout life. In addition to cell-intrinsic regulation, extrinsic cues within the bone marrow niche and systemic factors also affect the fate of HSCs. Despite this, many paracrine and endocrine factors that influence the function of hematopoietic cells remain unknown. In hematological malignancies, malignant cells remodel their niche into a permissive environment to enhance the survival of leukemic cells. These events are accompanied by loss of normal hematopoiesis. It is well known that extracellular vehicles (EVs) mediate intracellular interactions under physiological and pathological conditions. In other words, EVs transfer biological information to surrounding cells and contribute not only to physiological functions but also to the pathogenesis of some diseases, such as cancers. Therefore, a better understanding of cell-to-cell interactions may lead to identification of potential therapeutic targets. Recent reports have suggested that EVs are evolutionarily conserved constitutive mediators that regulate hematopoiesis. Here, we focus on the emerging roles of EVs in normal and pathological conditions, particularly in hematological malignancies. Owing to the high abundance of EVs in biological fluids, their potential use as biomarkers and therapeutic tools is discussed.

Emerging concepts of migrasome: An up-and-coming organelle from biology to the clinic

Since the migrasome concept was first proposed in 2015, extensive research has been conducted on these novel organelles, which grow on retracted fibers at the posterior end of migrating cells. Recently, molecular markers, biological functions, and clinical values based on the initial formation mechanism of migrasomes have emerged. Additionally, researchers are recognizing the significant role that migrasomes play in the pathological and diagnostic processes of clinical diseases. In this review, we summarize recent advances in the biology and clinical application of migrasomes and provide a comprehensive view of the prospective challenges surrounding their clinical application.

Ultrasensitive quantification of PD-L1+ extracellular vesicles in melanoma patient plasma using a parallelized high throughput droplet digital assay

The expression of programmed death-ligand 1 (PD-L1) on extracellular vesicles (EVs) is an emerging biomarker for cancer, and has gained particular interest for its role mediating immunotherapy. However, precise quantification of PD-L1+ EVs in clinical samples remains challenging due to their sparse concentration and the enormity of the number of background EVs in human plasma, limiting applicability of conventional approaches. In this study, we develop a high-throughput droplet-based extracellular vesicle analysis (DEVA) assay for ultrasensitive quantification of EVs in plasma that are dual positive for both PD-L1 and tetraspanin (CD81) known to be expressed on EVs. We achieve a performance that significantly surpasses conventional approaches, demonstrating 360× enhancement in the limit of detection (LOD) and a 750× improvement in the limit of quantitation (LOQ) compared to conventional plate enzyme-linked immunoassay (ELISA). Underlying this performance is DEVA's high throughput analysis of individual EVs one at a time and the high specificity to targeted EVs versus background. We achieve a 0.006% false positive rate per droplet by leveraging avidity effects that arise from EVs having multiple copies of their target ligands on their surface. We use parallelized optofluidics to rapidly process 10 million droplets per minute, ∼100× greater than conventional approaches. A validation study on a cohort of 14 patients with melanoma confirms DEVA's ability to match conventional ELISA measurements with reduced plasma sample volume and without the need for prior EV purification. This proof-of-concept study demonstrates DEVA's potential for clinical utility to enhance prognosis as well as guide treatment for cancer.

Urinary exosomes: Potential diagnostic markers and application in bladder cancer

Background

The exosome is a critical component of the intercellular communication., playing a vital role in regulating cell function. These small vesicles contain proteins, mRNAs, miRNAs, and lncRNAs, surrounded by lipid bilayer substances. Most cells in the human body can produce exosomes, released into various body fluids such as urine, blood, and cerebrospinal fluid. Bladder cancer is the most common tumor in the urinary system, with high recurrence and metastasis rates. Early diagnosis and treatment are crucial for improving patient outcomes.

Methods

This study employed the PubMed search engine to retrieve publicly accessible data pertaining to urinary exosomes.

Results

We summarize the origins and intricate biological characteristics of urinary exosomes, the introduction of research methodologies used in basic experiments to isolate and analyze these exosomes, the discussion of their applications and progress in the diagnosis and treatment of bladder cancer, and the exploration of the current limitations associated with using urinary exosomes as molecular biomarkers for diagnosing bladder cancer.

Conclusion

Exosomes isolated from urine may be used as molecular biomarkers for early detection of bladder cancer.

Identification of Transcriptomic Signatures of Pancreatic Ductal Adenocarcinoma-Derived Exosomes That Promote Macrophage M2 Polarization and Predict Prognosis: S100A9 Reveals Tumor Progression

Background

Exosomes play a role in intercellular communication and participate in the interaction between pancreatic ductal adenocarcinoma (PDAC) cells and immune cells. Macrophages can receive tumor cell-derived exosomes to polarize into M2-type macrophages, which can enhance the invasion and metastasis of pancreatic cancer, leading to poor prognosis. However, the mechanism by which pancreatic cancer cell-derived exosomes promote M2-type macrophages is still unclear.

Methods

M2 macrophage-associated exosome-derived key module genes were identified by differentially expressed genes (DEGs) and weighted gene co-expression network analysis (WGCNA) analysis using exoRbase 2.0, The Cancer Genome Atlas (TCGA), and The International Cancer Genome Consortium (ICGC) databases. Multivariate Cox regression analysis was used to identify key prognostic genes and obtain regression coefficients to establish prognostic signature. Immune infiltration, tumor mutations, and GSEA among different risk groups were compared. exoRbase 2.0, Gene Expression Profiling Interactive Analysis 2 (GEPIA2), HPA, and TISCH2 databases were used to further analyze the expression pattern of S100A9 in pancreatic cancer. In vitro experiments, cell-derived exosome isolation, quantitative polymerase chain reaction (qPCR), western blot, flow cytometry analysis, cell transfection, transwell assay, and CCK-8 assay were applied to investigate the roles of S100A9 in macrophage M2 polarization and tumor progression.

Results

The key genes of PDAC-derived exosomes promoting M2-type macrophage polarization were identified, and a risk score model was established. The risk score is related to the expression of common immune checkpoints, immune score, and stromal score, and the tumor mutational burden and biological function of high- and low-risk groups were also different. S100A9 was positively correlated with M2-type macrophage marker. In addition, scRNA-seq data from the TISCH2 database revealed that S100A9 is predominantly expressed in pancreatic cancer cells and mono/macrophage cells, suggesting that S100A9 in pancreatic cancer cells could be received by macrophages, thereby inducing macrophage polarization. In vitro, we used exosomes from BxPC-3 cell lines to coculture macrophages and found that macrophages were mainly polarized toward M2 type, which further promoted the proliferation and metastasis of PDAC.

Conclusions

Our study established a reliable risk score model for PDAC-derived exosomes and M2 macrophages, identified the important role of S100A9 in macrophage M2 polarization, which provides a new strategy for the diagnosis and treatment of PDAC, and strengthened the understanding of the mechanism of tumor development and metastasis.

Extracellular vesicle-mediated ferroptosis, pyroptosis, and necroptosis: potential clinical applications in cancer therapy

Extracellular vesicles (EVs) have gained increasing recognition as significant regulators of intercellular communication in various physiological and pathological processes. These vesicles play a pivotal role in cancer progression by facilitating the transfer of diverse cargoes, including lipids, proteins, and nucleic acids. Regulated cell death (RCD), the orderly and autonomous death of cells, is controlled by a variety of biomacromolecules and, in turn, influences various biological processes and cancer progression. Recent studies have demonstrated that EV cargoes regulate diverse oncogenes and tumor suppressors to mediate different nonapoptotic forms of RCD, notably ferroptosis, pyroptosis, and necroptosis. Nevertheless, comprehensive exploration of EV-mediated nonapoptotic RCD forms in the context of cancer has not been performed. This review summarizes the progress regarding the biological functions and underlying mechanisms of EVs in mediating nonapoptotic RCD by delivery of cargoes to regulate tumor progression. Additionally, the review delves into the potential clinical applications of EV-mediated cell death and its significance in the areas of cancer diagnosis and therapy.

Genetically engineered nano-melittin vesicles for multimodal synergetic cancer therapy

Melittin, the principal constituent in bee venom, is an attractive candidate for cancer therapy. However, its clinical applications are limited by hemolysis, nonspecific cytotoxicity, and rapid metabolism. Herein, a novel genetically engineered vesicular antibody-melittin (VAM) drug delivery platform was proposed and validated for targeted cancer combination therapy. VAM generated from the cellular plasma membrane was bio-synthetically fabricated, with the recombinant protein (hGC33 scFv-melittin) being harbored and displayed on the cell membrane. The bioactive and targetable nanomelittin conjugated by hGC33 scFv could be released in an MMP14-responsive manner at tumor sites, which reduced off-target toxicity, especially the hemolytic activity of melittin. Importantly, VAM could be loaded with small-molecule drugs or nanoparticles for combination therapy. Nanomelittin formed pores in membranes and disturbed phospholipid bilayers, which allowed the anticancer agents (i.e., chemotherapeutic drug doxorubicin and sonosensitizer purpurin 18 nanoparticles) co-delivered by VAM to penetrate deeper tumor sites, leading to synergistic therapeutic effects. In particular, the punching effect generated by sonodynamic therapy further improved the immunomodulatory effect of nanomelittin to activate the immune response. Taken together, our findings indicate that clinically translatable VAM-based strategies represent a universal, promising approach to multimodal synergetic cancer therapy.

The role of mesenchymal stem cells derived exosomes as a novel nanobiotechnology target in the diagnosis and treatment of cancer

Mesenchymal stem cells (MSCs), one of the most common types of stem cells, are involved in the modulation of the tumor microenvironment (TME). With the advancement of nanotechnology, exosomes, especially exosomes secreted by MSCs, have been found to play an important role in the initiation and development of tumors. In recent years, nanobiotechnology and bioengineering technology have been gradually developed to detect and identify exosomes for diagnosis and modify exosomes for tumor treatment. Several novel therapeutic strategies bioengineer exosomes to carry drugs, proteins, and RNAs, and further deliver their encapsulated cargoes to cancer cells through the properties of exosomes. The unique properties of exosomes in cancer treatment include targeting, low immunogenicity, flexibility in modification, and high biological barrier permeability. Nevertheless, the current comprehensive understanding of the roles of MSCs and their secreted exosomes in cancer development remain inadequate. It is necessary to better understand/update the mechanism of action of MSCs-secreted exosomes in cancer development, providing insights for better modification of exosomes through bioengineering technology and nanobiotechnology. Therefore, this review focuses on the role of MSCs-secreted exosomes and bioengineered exosomes in the development, progression, diagnosis, and treatment of cancer.

EXOSOMES AND MICROVESICLES FROM ADIPOSE-DERIVED MESENCHYMAL STEM CELLS PROTECTS THE ENDOTHELIAL GLYCOCALYX FROM LPS INJURY

ABSTRACT

Introduction: Endothelial glycocalyx damage occurs in numerous pathological conditions and results in endotheliopathy. Extracellular vesicles, including exosomes and microvesicles, isolated from adipose-derived mesenchymal stem cells (ASCs) have therapeutic potential in multiple disease states; however, their role in preventing glycocalyx shedding has not been defined. We hypothesized that ASC-derived exosomes and microvesicles would protect the endothelial glycocalyx from damage by LPS injury in cultured endothelial cells. Methods : Exosomes and microvesicles were collected from ASC conditioned media by centrifugation (10,000 g for microvesicles, 100,000 g for exosomes). Human umbilical vein endothelial cells (HUVECs) were exposed to 1 μg/mL lipopolysaccharide (LPS). LPS-injured cells (n = 578) were compared with HUVECS with concomitant LPS injury plus 1.0 μg/mL of exosomes (n = 540) or microvesicles (n = 510) for 24 hours. These two cohorts were compared with control HUVECs that received phosphate-buffered saline only (n = 786) and HUVECs exposed to exosomes (n = 505) or microvesicles (n = 500) alone. Cells were fixed and stained with FITC-labeled wheat germ agglutinin to quantify EGX. Real-time quantitative reverse-transcription polymerase chain reaction was used on HUVECs cell lystate to quantify hyaluron synthase-1 (HAS1) expression. Results: Exosomes alone decreased endothelial glycocalyx staining intensity when compared with control (4.94 vs. 6.41 AU, P < 0.001), while microvesicles did not cause a change glycocalyx staining intensity (6.39 vs. 6.41, P = 0.99). LPS injury resulted in decreased glycocalyx intensity as compared with control (5.60 vs. 6.41, P < 0.001). Exosomes (6.85 vs. 5.60, P < 0.001) and microvesicles (6.35 vs. 5.60, P < 0.001) preserved endothelial glycocalyx staining intensity after LPS injury. HAS1 levels were found to be higher in the exosome (1.14 vs. 3.67 RE, P = 0.02) and microvesicle groups (1.14 vs. 3.59 RE, P = 0.02) when compared with LPS injury. Hyaluron synthase-2 and synthase-3 expressions were not different in the various experimental groups. Conclusions: Exosomes alone can damage the endothelial glycocalyx. However, in the presence of LPS injury, both exosomes and microvesicles protect the glycocalyx layer. This effect seems to be mediated by HAS1. Level of Evidence : Basic science study.

Emerging extracellular vesicle-based carriers for glioblastoma diagnosis and therapy

Glioblastoma (GBM) treatment is still a big clinical challenge because of its highly malignant, invasive, and lethal characteristics. After treatment with the conventional therapeutic paradigm of surgery combined with radio- and chemotherapy, patients bearing GBMs generally exhibit a poor prognosis, with high mortality and a high disability rate. The main reason is the existence of the formidable blood-brain barrier (BBB), aggressive growth, and the infiltration nature of GBMs. Especially, the BBB suppresses the delivery of imaging and therapeutic agents to lesion sites, and thus this leads to difficulties in achieving a timely diagnosis and treatment. Recent studies have demonstrated that extracellular vesicles (EVs) exhibit favorable merits including good biocompatibility, a strong drug loading capacity, long circulation time, good BBB crossing efficiency, specific targeting to lesion sites, and high efficiency in the delivery of a variety of cargos for GBM therapy. Importantly, EVs inherit physiological and pathological molecules from the source cells, which are ideal biomarkers for molecularly tracking the malignant progression of GBMs. Herein, we start by introducing the pathophysiology and physiology of GBMs, followed by presenting the biological functions of EVs in GBMs with a special focus on their role as biomarkers for GBM diagnosis and as messengers in the modulation of the GBM microenvironment. Furthermore, we provide an update on the recent progress of using EVs in biology, functionality, and isolation applications. More importantly, we systematically summarize the most recent advances of EV-based carriers for GBM therapy by delivering different drugs including gene/RNA-based drugs, chemotherapy drugs, imaging agents, and combinatory drugs. Lastly, we point out the challenges and prospects of future research on EVs for diagnosing and treating GBMs. We hope this review will stimulate interest from researchers with different backgrounds and expedite the progress of GBM treatment paradigms.

Metastatic Dissemination: Role of Tumor-Derived Extracellular Vesicles and Their Use as Clinical Biomarkers

Cancer is a major cause of mortality in humans; often, rather than the primary tumor, it is the presence of metastases that are the cause of death. Extracellular vesicles (EVs) are small structures released by both normal and cancer cells; regarding the latter, they have been demonstrated to modulate almost all cancer-related processes, such as invasion, angiogenesis induction, drug resistance, and immune evasion. In the last years, it has become clear how EVs are widely involved in metastatic dissemination as well as in pre-metastatic niche (PMN) formation. Indeed, in order to achieve a successful metastatic process, i.e., penetration by cancer cells into distant tissues, the shaping of a favorable environment into those distant tissue, i.e., PMN formation, is mandatory. This process consists of an alteration that takes place in a distant organ and paves the way for the engraftment and growth of circulating tumor cells derived from the tumor primary site. This review focuses on the role of EVs in pre-metastatic niche formation and metastatic dissemination, also reporting the last studies suggesting the EVs role as biomarkers of metastatic diseases, possibly in a liquid biopsy approach.

Extracellular Vesicles and Their Zeta Potential as Future Markers Associated with Nutrition and Molecular Biomarkers in Breast Cancer

A nutritional intervention promotes the loss of body and visceral fat while maintaining muscle mass in breast cancer patients. Extracellular vesicles (EVs) and their characteristics can be potential biomarkers of disease. Here, we explore the changes in the Zeta potential of EVs; the content of miRNA-30, miRNA-145, and miRNA-155; and their association with body composition and biomarkers of metabolic risk in breast cancer patients, before and 6 months after a nutritional intervention. Clinicopathological data (HER2neu, estrogen receptor, and Ki67), anthropometric and body composition data, and plasma samples were available from a previous study. Plasma EVs were isolated and characterized in 16 patients. The expression of miRNA-30, miRNA-145, and miRNA-155 was analyzed. The Zeta potential was associated with HER2neu (β = 2.1; p = 0.00), Ki67 (β = -1.39; p = 0.007), estrogen positive (β = 1.57; p = 0.01), weight (β = -0.09; p = 0.00), and visceral fat (β = 0.004; p = 0.00). miRNA-30 was associated with LDL (β = -0.012; p = 0.01) and HDL (β = -0.02; p = 0.05). miRNA-155 was associated with visceral fat (β = -0.0007; p = 0.05) and Ki67 (β = -0.47; p = 0.04). Our results reveal significant associations between the expression of miRNA-30 and miRNA-155 and the Zeta potential of the EVs with biomarkers of metabolic risk and disease prognosis in women with breast cancer; particularly, the Zeta potential of EVs can be a new biomarker sensitive to changes in the nutritional status and breast cancer progression.

Application of small extracellular vesicles in the diagnosis and prognosis of nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is a malignant tumor originating from the epithelium of the nasopharynx. The disease is insidious, and most patients are diagnosed at the advanced stage, resulting in poor prognosis. Early diagnosis is important to reduce NPC mortality. Small extracellular vesicles (sEVs) are rich in a variety of bioactive molecules, such as proteins, nucleic acids, and lipids, which can participate in the physiological and pathological regulation of the body by affecting the function of target cells. Numerous studies have shown that some RNAs and proteins in sEVs of tumor origin have a key role in the development of NPC and are potential candidates for malignancy detection. Studying the relationship between the cargoes of these sEVs and NPC may help in the diagnosis of the disease. Here in this review, we summarize the application of sEVs as biomarkers in the diagnosis of NPC and their role in NPC metastasis and prognosis. In addition, we discuss possible future applications and limitations of sEVs as biomarkers.

T cell-derived exosomes in tumor immune modulation and immunotherapy

Exosomes are nanoscale vesicles secreted by most cells and have a phospholipid bilayer structure. Exosomes contain DNA, small RNA, proteins, and other substances that can carry proteins and nucleic acids and participate in communication between cells. T cells are an indispensable part of adaptive immunity, and the functions of T cell-derived exosomes have been widely studied. In the more than three decades since the discovery of exosomes, several studies have revealed that T cell-derived exosomes play a novel role in cell-to-cell signaling, especially in the tumor immune response. In this review, we discuss the function of exosomes derived from different T cell subsets, explore applications in tumor immunotherapy, and consider the associated challenges.

Metabolomics of Extracellular Vesicles: A Future Promise of Multiple Clinical Applications

Extracellular vesicles (EVs) can contain DNA, RNA, proteins and metabolic molecules from primary origins; they are coated with a phospholipid bilayer membrane and released by cells into the extracellular matrix. EVs can be obtained from various body liquids, including the blood, saliva, cerebrospinal fluid, and urine. As has been proved, EVs-mediated transfer of biologically active molecules is crucial for various physiological and pathological processes. Extensive investigations have already begun to explore the diagnosis and prognosis potentials for EVs. Furthermore, research has continued to recognize the critical role of nucleic acids and proteins in EVs. However, our understanding of the comprehensive effects of metabolites in these nanoparticles is currently limited and in its infancy. Therefore, we have attempted to summarize the recent research into the metabolomics of EVs in relation to potential clinical applications and discuss the problems and challenges that have occurred, to provide more guidance for the future development in this field.

Functions and therapeutic potentials of exosomes in osteosarcoma

Osteosarcoma is a primary malignant tumor of the skeleton with the morbidity of 2.5 in 1 million. The regularly on-set is in the epiphysis of the extremities with a high possibility of early metastasis, rapid progression, and poor prognosis. The survival rate of patients with metastatic or recurrent osteosarcoma remains low, and novel diagnostic and therapeutic methods are urgently needed. Exosomes are extracellular vesicles 30-150 nm in diameter secreted by various cells that are widely present in various body fluids. Exosomes are abundant in biologically active components such as proteins, nucleic acids, and lipids. Exosomes participate in numerous physiological and pathological processes via intercellular substance exchange and signaling. This review presents the novel findings of exosomes in osteosarcoma in diagnosis, prognosis, and therapeutic aspects.

Cancer Three-Dimensional Spheroids Mimic In Vivo Tumor Features, Displaying “Inner” Extracellular Vesicles and Vasculogenic Mimicry

The role of extracellular vesicles (EVs) as mediators of cell-to-cell communication in cancer progression is widely recognized. In vitro studies are routinely performed on 2D culture models, but recent studies suggest that 3D cultures could represent a more valid model. Human ovarian cancer cells CABA I were cultured by the hanging drop method to form tumor spheroids, that were moved to low adhesion supports to observe their morphology by Scanning Electron Microscopy (SEM) and to isolate the EVs. EVs release was verified by SEM and their identity confirmed by morphology (Transmission Electron Microscopy, TEM), size distribution (Nanoparticles Tracking Analysis), and markers (CD63, CD9, TSG-101, Calnexin). CABA I form spheroids with a clinically relevant size, above 400 μm; they release EVs on their external surface and also trap “inner” EVs. They also produce vasculogenic mimicry-like tubules, that bulge from the spheroid and are composed of a hollow lumen delimited by tumor cells. CABA I can be grown as multicellular spheroids to easily isolate EVs. The presence of features typical of in vivo tumors (inner entrapped EVs and vasculogenic mimicry) suggests their use as faithful experimental models to screen therapeutic drugs targeting these pro-tumorigenic processes.

Extracellular vesicles: A new diagnostic biomarker and targeted drug in osteosarcoma

Osteosarcoma (OS) is a primary bone cancer that is highly prevalent among adolescents and adults below the age of 20 years. The prognostic outcome of metastatic OS or relapse is extremely poor; thus, developing new diagnostic and therapeutic strategies for treating OS is necessary. Extracellular vesicles (EVs) ranging from 30–150 nm in diameter are commonly produced in different cells and are found in various types of body fluids. EVs are rich in biologically active components like proteins, lipids, and nucleic acids. They also strongly affect pathophysiological processes by modulating the intercellular signaling pathways and the exchange of biomolecules. Many studies have found that EVs influence the occurrence, development, and metastasis of osteosarcoma. The regulation of inflammatory communication pathways by EVs affects OS and other bone-related pathological conditions, such as osteoarthritis and rheumatoid arthritis. In this study, we reviewed the latest findings related to diagnosis, prognosis prediction, and the development of treatment strategies for OS from the perspective of EVs.

Exosomes as Crucial Players in Pathogenesis of Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that affects multiple systems. Its clinical manifestation varies across patients, from skin mucosa to multiorgan damage to severe central nervous system involvement. The exosome has been shown to play an important role in the pathogenesis of autoimmune diseases, including SLE. We review the recent knowledge of exosomes, including their biology, functions, mechanism, and standardized extraction and purification methods in SLE, to highlight potential therapeutic targets for SLE.

High-Resolution Secretome Analysis of Chemical Hypoxia Treated Cells Identifies Putative Biomarkers of Chondrosarcoma

Chondrosarcoma is the second most common bone tumor, accounting for 20% of all cases. Little is known about the pathology and molecular mechanisms involved in the development and in the metastatic process of chondrosarcoma. As a consequence, there are no approved therapies for this tumor and surgical resection is the only treatment currently available. Moreover, there are no available biomarkers for this type of tumor, and chondrosarcoma classification relies on operator-dependent histopathological assessment. Reliable biomarkers of chondrosarcoma are urgently needed, as well as greater understanding of the molecular mechanisms of its development for translational purposes. Hypoxia is a central feature of chondrosarcoma progression. The hypoxic tumor microenvironment of chondrosarcoma triggers a number of cellular events, culminating in increased invasiveness and migratory capability. Herein, we analyzed the effects of chemically-induced hypoxia on the secretome of SW 1353, a human chondrosarcoma cell line, using high-resolution quantitative proteomics. We found that hypoxia induced unconventional protein secretion and the release of proteins associated to exosomes. Among these proteins, which may be used to monitor chondrosarcoma development, we validated the increased secretion in response to hypoxia of glyceraldehyde 3-phosphate dehydrogenase (GAPDH), a glycolytic enzyme well-known for its different functional roles in a wide range of tumors. In conclusion, by analyzing the changes induced by hypoxia in the secretome of chondrosarcoma cells, we identified molecular mechanisms that can play a role in chondrosarcoma progression and pinpointed proteins, including GAPDH, that may be developed as potential biomarkers for the diagnosis and therapeutic management of chondrosarcoma.

PLGA Containing Human Adipose-Derived Stem Cell-Derived Extracellular Vesicles Accelerates the Repair of Alveolar Bone Defects via Transfer of CGRP

Calcitonin gene-related peptide (CGRP) is an important neuropeptide expressed in the nerve fibers during bone repair. Here, we aimed to pinpoint the role of CGRP in the osteogenic differentiation property of human periodontal ligament stem cells (hPDLSCs) and the resultant repair of alveolar bone defect. The key factor related to the osteogenic differentiation of hPDLSCs was retrieved from the GEO database. After extraction from hADSCs (hADSC-EVs) and identification, EVs were subjected to coculture with hPDLSCs, in which the expression patterns of CGRP and osteogenic differentiation marker proteins (ALP, RUNX2, and OCN), as well as ALP activity, were detected. A novel cell-free tissue-engineered bone (TEB) comprised of PLGA/pDA and hADSC-EVs was implanted into the rats with alveolar bone defects to evaluate the repair of alveolar bone defects. CGRP was enriched in hADSC-EVs. hADSCs delivered CGRP to hPDLSCs through EVs, thereby promoting the osteogenic differentiation potential of hPDLSCs. The PLGA/pDA-EV scaffold released EVs slowly, and its implantation into the rat alveolar bone defect area significantly induced bone defect repair, which was reversed by further knockdown of CGRP. In conclusion, our newly discovered cell-free system consisted of hADSC-EVs, and PLGA/pDA scaffold shows promising function in repairing alveolar bone defects.

Pharmacological mechanism of xanthoangelol underlying Nrf-2/TRPV1 and anti-apoptotic pathway against scopolamine-induced amnesia in mice

Alzheimer's disease (AD) is a well-known type of age-related dementia. The present study was conducted to investigate the effect of xanthoangelol against memory deficit and neurodegeneration associated with AD. Preliminarily, xanthoangelol produced neuroprotective effect against H₂O₂-induced HT-22 cells. Furthermore, effect of xanthoangelol against scopolamine-induced amnesia in mice was determined by intraperitoneally (i.p.) administering xanthoangelol (1, 10 and 20 mg/kg), 30 min prior to induction. Mice were administered scopolamine at a concentration of 1 mg/kg; i.p. for the induction of amnesia associated with AD. Xanthoangelol dose dependently reduced the symptoms of Alzheimer's disease as observed by the results obtained from the behavioral analysis performed using Morris water maze and Y-maze test. The immunohistochemical analysis suggested that xanthoangelol significantly improved Keap-1/Nrf-2 signaling pathway. It greatly reduced the effects of oxidative stress and showed improvement in the anti-oxidant enzyme such as GSH, GST, SOD and catalase. Additionally, xanthoangelol decreased the expression of transient receptor potential vanilloid 1 (TRPV-1), a nonselective cation channel, involved in synaptic plasticity and memory. It activated the anti-oxidants and attenuated the apoptotic (Bax/Bcl-2) pathway. Xanthoangelol also significantly attenuated the scopolamine-induced neuroinflammation by the inhibition of interleukin-1 beta (IL-1β), and tumor necrosis factor-α (TNF-α) levels. The histological analysis, showed a significant reduction in amyloid plaques by xanthoangelol. Therefore, the present study indicated that xanthoangelol has the ability to ameliorate the AD symptoms by attenuating neuroinflammation and neurodegeneration induced by scopolamine.

The potential role of extracellular vesicles in bioactive compound-based therapy: A review of recent developments

Recent studies have explored the field of extracellular vesicles (EVs), driving an increasing interest in their application to human health. EVs have unique physicochemical traits to participate in intercellular communication, thus fostering the idea of using EVs to yield synergistic, preventive, and therapeutic effects. Many reports have shown that EVs contain natural bioactive compounds, such as lipids, proteins, RNA, and other active components that regulate biological processes, thereby contributing to human health. Therefore, in this review, we comprehensively elucidate various facets of the relationship between EVs and bioactive compounds that modulate EVs contents, including RNAs and proteins, discussing different forms of biological regulation. The use of EVs for cargo-loading bioactive compounds to exert biological functions and methods to load bioactive compounds into EVs are also discussed. This review highlighted the effect of EV-delivered bioactive compounds on several therapeutic mechanisms and applications, providing new insight into nutrition and pharmacology.

Studies of the Efficacy of Low-Dose Apatinib Monotherapy as Third-Line Treatment in Patients with Metastatic Colorectal Cancer and Apatinib’s Novel Anticancer Effect by Inhibiting Tumor-Derived Exosome Secretion

Simple Summary

We assessed the efficacy and safety of low-dose apatinib monotherapy as a third-line treatment in patients with metastatic colorectal cancer. The ORR and DCR were 4.0% (2/50) and 70% (35/50), and the median PFS and OS were 4.7 months and 10.1 months, which demonstrated comparable survival outcomes, significant improvements to the patient’s quality of life, and tolerable adverse reactions. We also disclosed a novel role of apatinib’s anticancer effect, i.e., inhibiting tumor-derived exosome release. Our results indicated that apatinib treatment inhibited exosome secretion through the regulation of MVB biogenesis, transport, and fusion by regulating LAMP2, RAB11, Snap23, and VAMP2. This novel regulatory mechanism provides a new perspective for the antitumor effect of apatinib in CRC treatment.

Abstract

Antiangiogenic therapy is an important treatment strategy for metastatic colorectal cancer (mCRC). We carried out a clinical study of low-dose apatinib (250 mg) monotherapy as a third-line treatment in patients with mCRC and assessed its efficacy and safety. It demonstrated that low-dose apatinib had comparable survival outcomes, significantly improved the patient quality of life, and caused tolerable adverse reactions. To further investigate the underlying mechanism of the effects of apatinib in CRC besides angiogenesis, we performed RNA-seq, and our results suggested that apatinib may have other potential antitumor mechanisms in CRC through multiple pathways, including exosomes secretion. In RKO and HCT116 cells, apatinib significantly reduced exosomes secretion by targeting multivesicular body (MVB) transport. Further studies have indicated that apatinib not only promoted the degradation of MVBs via the regulation of LAMP2 but also interfered with MVB transport by inhibiting Rab11 expression. Moreover, apatinib inhibited MVB membrane fusion by reducing SNAP23 and VAMP2 expression. In vivo, apatinib inhibited orthotopic murine colon cancer growth and metastasis and reduced the serum exosomes amount. This novel regulatory mechanism provides a new perspective for the antitumor effect of apatinib beyond angiogenesis inhibition.

Extracellular Vesicle (EV) Dot Blotting for Multiplexed EV Protein Detection in Complex Biofluids

Extracellular vesicles (EVs) are nanoscale vesicles secreted from cells, carrying biomolecular cargos similar to their cells of origin. Measuring the protein content of EVs in biofluids can offer a crucial insight into human health and disease. For example, detecting tumor-derived EVs' protein markers can aid in early diagnosis of cancer, which is life-saving. In order to use these EV proteins for diagnosis, sensitive and multiplexed methods are required. The current methods for EV protein detection typically require large sample consumption due to challenges with sensitivity and often need an EV isolation step for complex biofluid samples such as blood plasma. In this work, we have developed a simple and sensitive method for multiplexed detection of protein markers on EV membrane surfaces, which we call "EV dot blotting", inspired by conventional dot blotting techniques. After optimization of multiple factors such as antibody concentration, blocking reagent, type of 3D membranes, and use of gold nanoparticles for signal enhancement, cancer-cell-derived EVs were spiked in pooled normal human plasma for conducting a multiplexed assay in a microarray format. Without the need of isolating EVs from blood plasma, a limit of detection of 3.1 × 10⁵ EVs/mL or 1863 EVs/sample was achieved for CD9 protein, 4.7 × 10⁴ EVs/mL or 281 EVs/sample for CD24, and 9.0 × 10⁴ EVs/mL or 538 EVs/sample for EpCAM, up to 4 orders of magnitude lower than those of conventional ELISA. This platform offers sensitive, multiplexed, simple, and low-cost EV protein detection directly from complex biofluids with minimal sample consumption, providing a useful tool for multiplexed EV protein quantification for a variety of applications.

Microfluidic Size Exclusion Chromatography (μSEC) for Extracellular Vesicles and Plasma Protein Separation

Extracellular vesicles (EVs) are recognized as next generation diagnostic biomarkers due to their disease-specific biomolecular cargoes and importance in cell-cell communications. A major bottleneck in EV sample preparation is the inefficient and laborious isolation of nanoscale EVs (≈50-200 nm) from endogenous proteins in biological samples. Herein, a unique microfluidic platform is reported for EV-protein fractionation based on the principle of size exclusion chromatography (SEC). Using a novel rapid (≈20 min) replica molding technique, a fritless microfluidic SEC device (μSEC) is fabricated using thiol-ene polymer (UV glue NOA81, Young's modulus ≈1 GPa) for high pressure (up to 6 bar) sample processing. Controlled on-chip nanoliter sample plug injection (600 nL) using a modified T-junction injector is first demonstrated with rapid flow switching response time (<1.5 s). Device performance is validated using fluorescent nanoparticles (50 nm), albumin, and breast cancer cells (MCF-7)-derived EVs. As a proof-of-concept for clinical applications, EVs are directly isolated from undiluted human platelet-poor plasma using μSEC and show distinct elution profiles between EVs and proteins based on nanoparticle particle analysis (NTA), Western blot and flow cytometry analysis. Overall, the optically transparent μSEC can be readily automated and integrated with EV detection assays for EVs manufacturing and clinical diagnostics.

Advances in the Application of Exosomes Identification Using Surface-Enhanced Raman Spectroscopy for the Early Detection of Cancers

Exosomes are small nanoscale vesicles with a double-layered lipid membrane structure secreted by cells, and almost all types of cells can secrete exosomes. Exosomes carry a variety of biologically active contents such as nucleic acids and proteins, and play an important role not only in intercellular information exchange and signal transduction, but also in various pathophysiological processes in the human body. Surface-enhanced Raman Spectroscopy (SERS) uses light to interact with nanostructured materials such as gold and silver to produce a strong surface plasmon resonance effect, which can significantly enhance the Raman signal of molecules adsorbed on the surface of nanostructures to obtain a rich fingerprint of the sample itself or Raman probe molecules with ultra-sensitivity. The unique advantages of SERS, such as non-invasive and high sensitivity, good selectivity, fast analysis speed, and low water interference, make it a promising technology for life science and clinical testing applications. In this paper, we briefly introduce exosomes and the current main detection methods. We also describe the basic principles of SERS and the progress of the application of unlabeled and labeled SERS in exosome detection. This paper also summarizes the value of SERS-based exosome assays for early tumor diagnosis.

The potential role of exosomal circRNAs in the tumor microenvironment: insights into cancer diagnosis and therapy

Exosomes are multifunctional regulators of intercellular communication by carrying various messages under both physiological and pathological status of cancer patients. Accumulating studies have identified the presence of circular RNAs (circRNAs) in exosomes with crucial regulatory roles in diverse pathophysiological processes. Exosomal circRNAs derived from donor cells can modulate crosstalk with recipient cells locally or remotely to enhance cancer development and propagation, and play crucial roles in the tumor microenvironment (TME), leading to significant enhancement of tumor immunity, metabolism, angiogenesis, drug resistance, epithelial mesenchymal transition (EMT), invasion and metastasis. In this review, we describe the advances of exosomal circRNAs and their roles in modulating cancer hallmarks, especially those in the TME. Moreover, clinical application potential of exosomal circRNAs in cancer diagnosis and therapy are highlighted, bridging the gap between basic knowledge and clinical practice.

In sickness and in health: The functional role of extracellular vesicles in physiology and pathology in vivo: Part II: Pathology: Part II: Pathology

It is clear from Part I of this series that extracellular vesicles (EVs) play a critical role in maintaining the homeostasis of most, if not all, normal physiological systems. However, the majority of our knowledge about EV signalling has come from studying them in disease. Indeed, EVs have consistently been associated with propagating disease pathophysiology. The analysis of EVs in biofluids, obtained in the clinic, has been an essential of the work to improve our understanding of their role in disease. However, to interfere with EV signalling for therapeutic gain, a more fundamental understanding of the mechanisms by which they contribute to pathogenic processes is required. Only by discovering how the EV populations in different biofluids change-size, number, and physicochemical composition-in clinical samples, may we then begin to unravel their functional roles in translational models in vitro and in vivo, which can then feedback to the clinic. In Part II of this review series, the functional role of EVs in pathology and disease will be discussed, with a focus on in vivo evidence and their potential to be used as both biomarkers and points of therapeutic intervention.

Diverse RNAs in adipose-derived extracellular vesicles and their therapeutic potential

Adipose tissue, which is considered an energy storage and active endocrine organ, produces and secretes a large amount of adipokines to regulate distant targets through blood circulation, especially extracellular vesicles (EVs). As cell-derived, membranous nanoparticles, EVs have recently garnered great attention as novel mediators in establishing intercellular communications as well as in accelerating interorgan crosstalk. Studies have revealed that the RNAs, including coding RNAs (messenger RNAs) and noncoding RNAs (long noncoding RNAs, microRNAs, and circular RNAs) are key bioactive cargoes of EV functions in various pathophysiological processes, such as cell differentiation, metabolic homeostasis, immune signal transduction, and cancer. Moreover, certain EV-contained RNAs have gradually been recognized as novel biomarkers, prognostic indicators, or even therapeutic nanodrugs of diseases. Therefore, in this review, we comprehensively summarize different classes of RNAs presented in adipose-derived EVs and discuss their therapeutic potential according to the latest research progress to provide valuable knowledge in this area.

Liquid biopsy approach to pancreatic cancer

Pancreatic cancer (PC) continues to pose a major clinical challenge. There has been little improvement in patient survival over the past few decades, and it is projected to become the second leading cause of cancer mortality by 2030. The dismal 5-year survival rate of less than 10% after the diagnosis is attributable to the lack of early symptoms, the absence of specific biomarkers for an early diagnosis, and the inadequacy of available chemotherapies. Most patients are diagnosed when the disease has already metastasized and cannot be treated. Cancer interception is vital, actively intervening in the malignization process before the development of a full-blown advanced tumor. An early diagnosis of PC has a dramatic impact on the survival of patients, and improved techniques are urgently needed to detect and evaluate this disease at an early stage. It is difficult to obtain tissue biopsies from the pancreas due to its anatomical position; however, liquid biopsies are readily available and can provide useful information for the diagnosis, prognosis, stratification, and follow-up of patients with PC and for the design of individually tailored treatments. The aim of this review was to provide an update of the latest advances in knowledge on the application of carbohydrates, proteins, cell-free nucleic acids, circulating tumor cells, metabolome compounds, exosomes, and platelets in blood as potential biomarkers for PC, focusing on their clinical relevance and potential for improving patient outcomes.

Circ-SFMBT2 drives the malignant phenotypes of esophageal cancer by the miR-107-dependent regulation of SLC1A5

Background

Increasing studies focused on the regulatory roles of circular RNAs (circRNAs) in diverse cancers. This study was to evaluate the function and mechanism of circRNA Scm-like with four malignant brain tumor domains 2 (circ-SFMBT2) in esophageal cancer (EC).

Methods

The circ-SFMBT2, microRNA-107 (miR-107) and solute-linked carrier family A1 member 5 (SLC1A5) levels were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was evaluated by 3-(4, 5-dimethylthiazol-2-y1)-2, 5-diphenyl tetrazolium bromide (MTT) assay, colony formation assay and EdU assay. Cell apoptosis and invasion were detected by flow cytometry and transwell assay. Glutamine metabolism was assessed by the corresponding kits for glutamine consumption, α-ketoglutarate production and glutamate production. Western blot was used for protein quantification. The binding analysis was performed using dual-luciferase reporter assay, RNA immunoprecipitation (RIP) and pull-down assays. The functional research of circ-SFMBT2 in vivo was performed by xenograft tumor assay. Exosomes were identified by morphological observation and protein detection.

Results

Circ-SFMBT2 was overexpressed in EC samples and cells. Circ-SFMBT2 downregulation inhibited EC cell proliferation, invasion and glutamine metabolism. Circ-SFMBT2 targeted miR-107 and the regulation of circ-SFMBT2 was achieved by sponging miR-107. SLC1A5 was a target of miR-107, and it worked as an oncogene in EC cells. MiR-107 retarded the EC progression by downregulating SLC1A5. Circ-SFMBT2 could affect the SLC1A5 expression by targeting miR-107. Circ-SFMBT2 regulated EC progression in vivo by miR-107/SLC1A5 axis. Circ-SFMBT2 was transferred by exosomes in EC cells.

Conclusion

These results suggested that circ-SFMBT2 upregulated the SLC1A5 expression to promote the malignant development of EC by serving as a miR-107 sponge.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02156-8.

The role and application of small extracellular vesicles in gastric cancer

Gastric cancer (GC) is a common tumour that affects humans worldwide, is highly malignant and has a poor prognosis. Small extracellular vesicles (sEVs), especially exosomes, are nanoscale vesicles released by various cells that deliver bioactive molecules to recipient cells, affecting their biological characteristics, changing the tumour microenvironment and producing long-distance effects. In recent years, many studies have clarified the mechanisms by which sEVs function with regard to the initiation, progression, angiogenesis, metastasis and chemoresistance of GC. These molecules can function as mediators of cell-cell communication in the tumour microenvironment and might affect the efficacy of immunotherapy. Due to their unique physiochemical characteristics, sEVs show potential as effective antitumour vaccines as well as drug carriers. In this review, we summarize the roles of sEVs in GC and highlight the clinical application prospects in the future.

Current perspectives on exosomes in the diagnosis and treatment of hepatocellular carcinoma (review)

The prognosis of hepatocellular carcinoma (HCC), a malignant tumor, is poor. Tumor recurrence and metastasis are the major challenges for the treatment of HCC. Various studies have demonstrated that exosomes, which are loaded with various biomolecules including nucleic acids, lipids, and proteins are involved in the recurrence and metastasis of HCC. Additionally, exosomes mediate various biological processes, such as immune response, cell apoptosis, angiogenesis, thrombosis, autophagy, and intercellular signal transduction. In cancer, exosomes regulate cancer cell differentiation, development, and drug resistance. Circular RNAs, microRNAs, and proteins in the exosomes can serve as early diagnostic and prognostic markers for HCC. As exosomes are characterized by low immunogenicity and high stability in the tissues and circulation, they can be used to deliver the drugs in cancer therapies.

Detection and Investigation of Extracellular Vesicles in Serum and Urine Supernatant of Prostate Cancer Patients

Prostate Cancer (PCa) is one of the most frequently identified urological cancers. PCa patients are often over-diagnosed due to still not highly specific diagnostic methods. The need for more accurate diagnostic tools to prevent overestimated diagnosis and unnecessary treatment of patients with non-malignant conditions is clear, and new markers and methods are strongly desirable. Extracellular vesicles (EVs) hold great promises as liquid biopsy-based markers. Despite the biological and technical issues present in their detection and study, these particles can be found highly abundantly in the biofluid and encompass a wealth of macromolecules that have been reported to be related to many physiological and pathological processes, including cancer onset, metastasis spreading, and treatment resistance. The present study aims to perform a technical feasibility study to develop a new workflow for investigating EVs from several biological sources. Serum and urinary supernatant EVs of PCa, benign prostatic hyperplasia (BPH) patients, and healthy donors were isolated and investigated by a fast, easily performable, and cost-effective cytofluorimetric approach for a multiplex detection of 37 EV-antigens. We also observed significant alterations in serum and urinary supernatant EVs potentially related to BPH and PCa, suggesting a potential clinical application of this workflow.