Exosomes: composition, biogenesis, and mechanisms in cancer metastasis and drug resistance

Exosomes: the next-generation therapeutic platform for ischemic stroke

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional recovery. Therefore, there is an urgent need to develop new methods for the treatment of this condition. Exosomes are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological conditions. They have low immunogenicity, good stability, high delivery efficiency, and the ability to cross the blood-brain barrier. These physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic stroke. The rapid development of nanotechnology has advanced the application of engineered exosomes, which can effectively improve targeting ability, enhance therapeutic efficacy, and minimize the dosages needed. Advances in technology have also driven clinical translational research on exosomes. In this review, we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke, including their anti-inflammation, anti-apoptosis, autophagy-regulation, angiogenesis, neurogenesis, and glial scar formation reduction effects. However, it is worth noting that, despite their significant therapeutic potential, there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified exosomes. Future optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic stroke. Ultimately, our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

Integration of single-nucleus and exosome RNA sequencing dissected inter-cellular communication and biomarkers in pancreatic ductal adenocarcinoma

Background

Mounting evidence underscores the importance of cell communication within the tumor microenvironment, which is pivotal in tumor proliferation, invasion, and metastasis. Exosomes play a crucial role in cell-to-cell communication. Although single-cell RNA sequencing (scRNA-seq) provides insights into individual cell transcriptional characteristics, it falls short of comprehensively capturing exosome-mediated intercellular communication.

Method

We analyzed Pancreatic Ductal Adenocarcinoma (PDAC) tissues, separating supernatant and precipitate for exosome purification and single-cell nucleus suspension. We then constructed Single-nucleus RNA sequencing (snRNA-seq) and small RNA-seq libraries from these components. Our bioinformatic analysis integrated these sequences with ligand-receptor analysis and public miRNA data to map the cell communication network.

Results

We established intercellular communication networks using bioinformatic analysis to track exosome miRNA effects and ligand-receptor pairs. Significantly, hsa-miR-1293 emerged as a prognostic biomarker for pancreatic cancer, linked to immune evasion, increased myeloid-derived suppressor cells, and poorer prognosis. Targeting this miRNA may enhance anti-tumor immunity and improve outcomes.

Conclusion

Our study offers a novel approach to constructing intercellular communication networks using snRNA-seq and exosome-small RNA sequencing. By integrating miRNA tracing with ligand-receptor analysis, we illuminate the complex interactions in the pancreatic cancer microenvironment, highlighting the pivotal role of miRNAs and identifying potential biomarkers and therapeutic targets.

Camouflaging nanoreactor traverse the blood-brain barrier to catalyze redox cascade for synergistic therapy of glioblastoma

The blood-brain barrier (BBB) is a complex and highly restrictive barrier that prevents most biomolecules and drugs from entering the brain. However, effective strategies for delivering drugs to the brain are urgently needed for the treatment of glioblastoma. Based on the efficient BBB penetration properties of exosomes derived from brain metastatic breast cancer cells (EB), this work prepared a nanoreactor (denoted as MAG@EB), which was constructed by self-assembly of Mn2+, arsenate and glucose oxidase (GOx) into nanoparticles wrapped with EB. MAG@EB can enhance the efficiency of traversing the BBB, target and accumulate at in situ glioblastoma sites. The GOx-driven glycolysis effectively cuts off the glucose supply while also providing an abundance of H2O2 and lowering pH. Meanwhile, the released Mn2+ mediated Fenton-like reaction converts elevated H2O2 into highly toxic ·OH. Besides, AsV was reduced to AsIII by glutathione, and the tumor suppressor gene P53 was activated by AsIII to kill glioblastoma cells. Glioblastoma succumbed to the redox cascade triggered by MAG@EB, as the results demonstrated in vivo and in vitro, yielding a remarkable therapeutic effect. This work provides a promising therapeutic option mediated by cascaded nanoreactors for the future treatment of glioblastoma.

Effects of total coumarins from Pileostegia tomentella on exosomal miRNA expression and angiogenesis in colorectal cancer cells

CONTEXT

Pileostegia tomentella Hand. Mazz (Saxifragaceae) total coumarins (TCPT) show antitumour activity in colorectal cancer (CRC) with unknown mechanism of action. Tumour angiogenesis mediated by exosomes-derived miRNA exhibits the vital regulation of endothelial cell function in metastasis of CRC.

OBJECTIVE

To investigate the effect of TCPT on exosomal miRNA expression and angiogenesis of CRC cells.

MATERIALS AND METHODS

HT-29-derived exosomes were generated from human CRC cells (HT-29) or either treated with TCPT (100 μg/mL) for 24 h, followed by identification by transmission electron microscope, nanoparticle tracking analysis (NTA) and Western blot. Co-culture experiments for human umbilical vein endothelial cells (HUVECs) and exosomes were performed to detect the uptake of exosomes in HUVECs and its influence on HUVECs cells migration and lumen formation ability. Potential target miRNAs in exosomes were screened out by sequencing technology. Rescue assays of angiogenesis were performed by the transfecting mimics or inhibitors of targeted miRNA into HUVECs.

RESULTS

HT-29-derived exosomes, after TCPT treatment (Exo-TCPT), inhibited the migration and lumen formation of HUVECs, reduced the expression levels of vascular marker (FLT-1, VCAM-1 and VEGFR-2) in HUVECs. Furthermore, the level of miR-375-3p was significantly upregulated in Exo-TCPT. Rescue assays showed that high expression of miR-375-3p in HUVECs inhibited migration and lumen formation abilities, which was consistent with the effects of Exo-TCPT, whereas applying miR-375-3p inhibitors displayed opposite effects.

DISCUSSION AND CONCLUSION

TCPT exhibits anti-angiogenesis in CRC, possibly through upregulating exosomal miR-375-3p. Our findings will shed light on new target exosomes miRNA-mediated tumour microenvironment and the therapeutic application of Pileostegia tomentella in CRC.

Role of tumor-derived exosomes mediated immune cell reprograming in cancer

Tumor-derived exosomes (TDEs), as topologies of tumor cells, not only carry biological information from the mother, but also act as messengers for cellular communication. It has been demonstrated that TDEs play a key role in inducing an immunosuppressive tumor microenvironment (TME). They can reprogram immune cells indirectly or directly by delivering inhibitory proteins, cytokines, RNA and other substances. They not only inhibit the maturation and function of dendritic cells (DCs) and natural killer (NK) cells, but also remodel M2 macrophages and inhibit T cell infiltration to promote immunosuppression and create a favorable ecological niche for tumor growth, invasion and metastasis. Based on the specificity of TDEs, targeting TDEs has become a new strategy to monitor tumor progression and enhance treatment efficacy. This paper reviews the intricate molecular mechanisms underlying the immunosuppressive effects induced by TDEs to establish a theoretical foundation for cancer therapy. Additionally, the challenges of TDEs as a novel approach to tumor treatment are discussed.

Small extracellular vesicles associated miRNA in myocardial fibrosis

Myocardial fibrosis involves the loss of cardiomyocytes, myocardial fibroblast proliferation, and a reduction in angiogenesis, ultimately leading to heart failure, Given its significant implications, it is crucial to explore novel therapies for myocardial fibrosis. Recently one emerging avenue has been the use of small extracellular vesicles (sEV)-carried miRNA. In this review, we summarize the regulatory role of sEV-carried miRNA in myocardial fibrosis. We explored not only the potential diagnostic value of circulating miRNA as biomarkers for heart disease but also the therapeutic implications of sEV-carried miRNA derived from various cellular sources and applications of modified sEV. This exploration is paramount for researchers striving to develop innovative, cell-free therapies as potential drug candidates for the management of myocardial fibrosis.

RNAs in tumour-derived extracellular vesicles and their significance in the tumour microenvironment

Small extracellular vesicles (sEVs) secreted by various types of cells serve as crucial mediators of intercellular communication within the complex tumour microenvironment (TME). Tumour-derived small extracellular vesicles (TDEs) are massively produced and released by tumour cells, recapitulating the specificity of their cell of origin. TDEs encapsulate a variety of RNA species, especially messenger RNAs, microRNAs, long non-coding RNAs, and circular RNAs, which release to the TME plays multifaced roles in cancer progression through mediating cell proliferation, invasion, angiogenesis, and immune evasion. sEVs act as natural delivery vehicles of RNAs and can serve as useful targets for cancer therapy. This review article provides an overview of recent studies on TDEs and their RNA cargo, with emphasis on the role of these RNAs in carcinogenesis.

Mesenchymal Stem Cell-Derived Extracellular Vesicles Protect Rat Nucleus Pulposus Cells from Oxidative Stress

BACKGROUND

Oxidative stress (OS) is mainly associated with the pathogenesis of intervertebral disc (IVD) degeneration; it causes nucleus pulposus cells (NPCs) to undergo senescence and triggers autophagy and apoptosis. This study aims to evaluate the regeneration potential of extracellular vesicles (EVs) derived from human umbilical cord-mesenchymal stem cells (hUC-MSCs) in an in vitro rat NPC-induced OS model.

DESIGN

NPCs were isolated from rat coccygeal discs, propagated, and characterized. OS was induced by hydrogen peroxide (H2O2), which is confirmed by 2,7-dichlorofluorescein diacetate (H2DCFDA) assay. EVs were isolated from hUC-MSCs and characterized by analyzing the vesicles using fluorescence microscope, scanning electron microscope (SEM), atomic force microscope (AFM), dynamic light scattering (DLS), and Western blot (WB). The in vitro effects of EVs on migration, uptake, and survival of NPCs were determined.

RESULTS

SEM and AFM topographic images revealed the size distribution of EVs. The phenotypes of isolated EVs showed that the size of EVs was 403.3 ± 85.94 nm, and the zeta potential was -0.270 ± 4.02 mV. Protein expression analysis showed that EVs were positive for CD81 and annexin V. Treatment of NPCs with EVs reduced H2O2-induced OS as evidenced by a decrease in reactive oxygen species (ROS) levels. Co-culture of NPCs with DiI-labeled EVs showed the cellular internalization of EVs. In the scratch assay, EVs significantly increased NPC proliferation and migration toward the scratched area. Quantitative polymerase chain reaction analysis showed that EVs significantly reduced the expression of OS genes.

CONCLUSION

EVs protected NPCs from H2O2-induced OS by reducing intracellular ROS generation and improved NPC proliferation and migration.

Exosomal long non-coding RNAs in cancer: Interplay, modulation, and therapeutic avenues

In the intricate field of cancer biology, researchers are increasingly intrigued by the emerging role of exosomal long non-coding RNAs (lncRNAs) due to their multifaceted interactions, complex modulation mechanisms, and potential therapeutic applications. These exosomal lncRNAs, carried within extracellular vesicles, play a vital partin tumorigenesis and disease progression by facilitating communication networks between tumor cells and their local microenvironment, making them an ideal candidates for use in a liquid biopsy approach. However, exosomal lncRNAs remain an understudied area, especially in cancer biology. Therefore this review aims to comprehensively explore the dynamic interplay between exosomal lncRNAs and various cellular components, including interactions with tumor-stroma, immune modulation, and drug resistance mechanisms. Understanding the regulatory functions of exosomal lncRNAs in these processes can potentially unveil novel diagnostic markers and therapeutic targets for cancer. Additionally, the emergence of RNA-based therapeutics presents exciting opportunities for targeting exosomal lncRNAs, offering innovative strategies to combat cancer progression and improve treatment outcomes. Thus, this review provides insights into the current understanding of exosomal lncRNAs in cancer biology, highlighting their crucial roles, regulatory mechanisms, and the evolving landscape of therapeutic interventions. Furthermore, we have also discussed the advantage of exosomes as therapeutic carriers of lncRNAs for the development of personalized targeted therapy for cancer patients.

ARHGAP4 promotes colon cancer metastasis through the TGF-β signaling pathway and may be associated with T cell exhaustion

BACKGROUND

Colon cancer is a prevalent invasive neoplasm in the gastrointestinal system with a high degree of malignancy. Despite extensive research, the underlying mechanisms of its recurrence and metastasis remain elusive.Rho GTPase activating protein 4 (ARHGAP4), a member of the small GTPases protein family, may be closely related to tumor metastasis, and its expression is increased in colon cancer. However, the role of ARHGAP4 in colon cancer metastasis is uncertain. This study investigates the impact of ARHGAP4 on the metastasis of colon cancer cells. Our objective is to determine the role of ARHGAP4 in regulating the invasive behavior of colon cancer cells.

METHODS

We downloaded colon adenocarcinoma (COAD) data from the Cancer Genome Atlas (TCGA), and performed differential analysis and survival analysis. By using the CIBERSORT algorithm, we evaluated the proportion of infiltrating immune cells in colon cancer. We further analyzed whether ARHGAP4 is associated with T cell exhaustion. Finally, we investigated the impact of ARHGAP4 knockdown on the migration and invasion of colon cancer cells through in vitro cell experiments. Additionally, we utilized western blotting to assess the expression of protein related to the TGF-β signaling pathway and epithelial-mesenchymal transition (EMT).

RESULTS

We found that ARHGAP4 is upregulated in colon cancer. Subsequent survival analysis revealed that the high-expression group had significantly lower survival rates compared to the low-expression group. Immune infiltration analysis showed that ARHGAP4 was not only positively correlated with CD8+ T cells, but also positively correlated with T cell exhaustion markers programmed cell death 1 (PDCD-1), cytotoxic T-lymphocyte associated protein 4 (CTLA-4), and lymphocyte activating 3 (LAG-3). In vitro cell experiments, the knockdown of ARHGAP4 inhibited the migration and invasion of colon cancer cells. Among EMT-related proteins, when ARHGAP4 was knocked down, the expression of E-cadherin was increased, while the expression of N-cadherin and Vimentin was decreased. Meanwhile, the expression of TGF-β1, p-Smad2, and p-Smad3, which are associated with the TGF-β/Smad pathway, all decreased.

CONCLUSION

ARHGAP4 promotes colon cancer metastasis through the TGF-β/Smad signaling pathway and may be associated with T cell exhaustion. It plays an important role in the progression of colon cancer and may serve as a potential target for diagnosis and treatment of colon cancer.

Transcriptional switches in melanoma T Cells: Facilitating polarizing into regulatory T cells

Melanoma is a malignant skin tumor with a high mortality rate. Regulatory T cells (Tregs) are immune cells with immunosuppressive roles, however, the precise mechanisms governing Treg involvement in melanoma remain enigmatic. Experimental findings unveiled different transcription factor switches between normal and tumor T cell, with heightened FOXP3 and BATF in the latter. These factors induced immunosuppressive molecules and Treg maintenance genes, polarizing tumor T cells into Tregs. Spatial transcriptomics illuminated the preferential settlement of Tregs at the melanoma periphery. Within this context, FOXP3 in Tregs facilitated direct enhancement of specific ligand gene expression, fostering communication with neighboring cells. Novel functional molecules bound to FOXP3 or BATF in Tregs, such as SPOCK2, SH2D2A, and ligand molecules ITGB2, LTA, CLEC2C, CLEC2D, were discovered, which had not been previously reported in melanoma Treg studies. Furthermore, we validated our findings in a large number of clinical samples and identified the Melanoma Treg-Specific Regulatory Tag Set (Mel TregS). ELISA analysis showed that the protein levels of Mel TregS in melanoma Tregs were higher than in normal Tregs. We then utilized SERS technology to measure the signal values of Mel TregS in exosome, and successfully discriminated between healthy individuals and melanoma patients, as well as early and late-stage patients. This approach significantly enhanced detection sensitivity. In sum, our research elucidated fresh insights into the mechanisms governing Treg self-maintenance and communication with surrounding cells in melanoma. We also introduced an innovative method for clinical disease monitoring through SERS technology.

Stem cell and exosome therapies for regenerating damaged myocardium in heart failure

Finding novel treatments for cardiovascular diseases (CVDs) is a hot topic in medicine; cell-based therapies have reported promising news for controlling dangerous complications of heart disease such as myocardial infarction (MI) and heart failure (HF). Various progenitor/stem cells were tested in various in-vivo, in-vitro, and clinical studies for regeneration or repairing the injured tissue in the myocardial to accelerate the healing. Fetal, adult, embryonic, and induced pluripotent stem cells (iPSC) have revealed the proper potency for cardiac tissue repair. As an essential communicator among cells, exosomes with specific contacts (proteins, lncRNAs, and miRNAs) greatly promote cardiac rehabilitation. Interestingly, stem cell-derived exosomes have more efficiency than stem cell transplantation. Therefore, stem cells induced pluripotent stem cells (iPSCs), embryonic stem cells (ESCs), cardiac stem cells (CDC), and skeletal myoblasts) and their-derived exosomes will probably be considered an alternative therapy for CVDs remedy. In addition, stem cell-derived exosomes have been used in the diagnosis/prognosis of heart diseases. In this review, we explained the advances of stem cells/exosome-based treatment, their beneficial effects, and underlying mechanisms, which will present new insights in the clinical field in the future.

Multi-targeted nanoarrays for early broad-spectrum detection of lung cancer based on blood biopsy of tumor exosomes

Liquid biopsies utilizing tumor exosomes offer a noninvasive approach for cancer diagnosis. However, validation studies consistently report that in the early stages of cancer, the secretion of exosomes by cancer cells is relatively low, while bodily fluids exhibit a high abundance of other interfering biomolecules. Additionally, target mutations or differences in biomarker expression among various lung cancer subtypes may contribute to detection failures. In this study, we propose a targeted nanoarray-based early cancer diagnostic approach for multiple subtypes of lung cancer. The targeted nanoarray was constructed by modifying five targeting aptamers onto mesoporous silica nanoparticles through the conjugation between amino and carboxyl groups. The flow cytometry experiments demonstrated the specific recognition ability of the targeted nanoarray to tumor exosomes in PBS, even at biomarker expression levels as low as 1.5 %. Moreover, the TEM results indicated that the targeted nanoarray could isolate tumor exosomes in the blood of tumor-bearing mice. Furthermore, the targeted nanoarray could detect tumor exosomes in the blood of various lung cancer bearing mice, including at the early stages of cancer, which has just been established for 7 days. Overall, the targeted nanoarray represents a promising tool for the early detection of various subtypes of lung cancer.

Extracellular vesicles reshape the tumor microenvironment to improve cancer immunotherapy: Current knowledge and future prospects

Tumor immunotherapy has revolutionized cancer treatment, but limitations remain, including low response rates and immune complications. Extracellular vesicles (EVs) are emerging as a new class of therapeutic agents for various diseases. Recent research shows that changes in the amount and composition of EVs can reshape the tumor microenvironment (TME), potentially improving the effectiveness of immunotherapy. This exciting discovery has sparked clinical interest in using EVs to enhance the immune system's response to cancer. In this Review, we delve into the world of EVs, exploring their origins, how they're generated, and their complex interactions within the TME. We also discuss the crucial role EVs play in reshaping the TME during tumor development. Specifically, we examine how their cargo, including molecules like PD-1 and non-coding RNA, influences the behavior of key immune cells within the TME. Additionally, we explore the current applications of EVs in various cancer therapies, the latest advancements in engineering EVs for improved immunotherapy, and the challenges faced in translating this research into clinical practice. By gaining a deeper understanding of how EVs impact the TME, we can potentially uncover new therapeutic vulnerabilities and significantly enhance the effectiveness of existing cancer immunotherapies.

New insights into the potential of exosomal circular RNAs in mediating cancer chemotherapy resistance and their clinical applications

Chemotherapy resistance typically leads to tumour recurrence and is a major obstacle to cancer treatment. Increasing numbers of circular RNAs (circRNAs) have been confirmed to be abnormally expressed in various tumours, where they participate in the malignant progression of tumours, and play important roles in regulating the sensitivity of tumours to chemotherapy drugs. As exosomes mediate intercellular communication, they are rich in circRNAs and exhibit a specific RNA cargo sorting mechanism. By carrying and delivering circRNAs, exosomes can promote the efflux of chemotherapeutic drugs and reduce intracellular drug concentrations in recipient cells, thus affecting the cell cycle, apoptosis, autophagy, angiogenesis, invasion and migration. The mechanisms that affect the phenotype of tumour stem cells, epithelial-mesenchymal transformation and DNA damage repair also mediate chemotherapy resistance in many tumours. Exosomal circRNAs are diagnostic biomarkers and potential therapeutic targets for reversing chemotherapy resistance in tumours. Currently, the rise of new fields, such as machine learning and artificial intelligence, and new technologies such as biosensors, multimolecular diagnostic systems and platforms based on circRNAs, as well as the application of exosome-based vaccines, has provided novel ideas for precision cancer treatment. In this review, the recent progress in understanding how exosomal circRNAs mediate tumour chemotherapy resistance is reviewed, and the potential of exosomal circRNAs in tumour diagnosis, treatment and immune regulation is discussed, providing new ideas for inhibiting tumour chemotherapy resistance.

Non-coding RNA in exosomes: Regulating bone metastasis of lung cancer and its clinical application prospect

Lung cancer is a highly prevalent malignancy with poor prognosis and rapid progression. It most frequently metastasizes to the bone, where it can pose a severe threat to the patient's survival. Once metastasized, the disease is often incurable and can result in severe complications such as hypercalcemia, bone pain, fractures, spinal cord compression, and subsequent paralysis. Exosomes are bilayer vesicle nanoparticles secreted by most of the extracellular vesicles, which can be found in almost all organisms and play an essential role in intercellular communication. Through their ability to regulate related bone cells, exosomes carry bioactive molecules, including proteins, lipids, and non-coding RNAs (ncRNAs), that can be extremely important in bone remodeling. Studies have been conducted on the role play by proteins, lncRNA, and microRNA-all ncRNAs-carried by exosomes in the bone metastases of lung cancer. In this review, the latest progress of the regulatory mechanism of ncRNAs carried by exosomes in lung cancer bone metastasis has been reviewed. The clinical use of exosomes as a promising biomarker, drug transporter, and therapeutic target was highlighted to offer a novel diagnostic and treatment approach for patients with lung cancer bone metastases.

Non-coding RNAs in hepatocellular carcinoma metastasis: Remarkable indicators and potential oncogenic mechanism

Non-coding RNAs (ncRNAs), as key regulators involving in intercellular biological processes, are more prominent in many malignancies, especially for hepatocellular carcinoma (HCC). Herein, we conduct a comprehensive review to summarize diverse ncRNAs roles in HCC metastatic mechanism. We focus on four signaling pathways that predominate in HCC metastatic process, including Wnt/β-catenin, HIF-1α, IL-6, and TGF-β pathways. MicroRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) employed different mechanisms to participate in the regulation of the key genes in these pathways, typical as interaction with DNA to control transcription, with RNA to control translation, and with protein to control stability. Therefore, ncRNAs may become potential biomarkers and therapeutic targets for HCC metastasis.

Therapeutic effect of small extracellular vesicles from cytokine-induced memory-like natural killer cells on solid tumors

Small extracellular vesicles (sEV) derived from diverse natural killer (NK) cell lines have proven their exceptional antitumor activities. However, sEV from human primary NK cells, especially memory-like NK cells, are rarely utilized for cancer treatment. In this study, we obtained sEV from IL-12, IL-15 and IL-18 cultured human memory-like NK cells (mNK-sEV) that showed strong cytokine-secretory ability. It was uncovered that mNK-sEV entered cancer cells via macropinocytosis and induced cell apoptosis via caspase-dependent pathway. Compared to sEV from conventionally cultured NK cells (conNK-sEV), mNK-sEV inhibited tumor growth to a greater extent. Concomitantly, pharmacokinetics and biodistribution results validated a higher accumulation of mNK-sEV than conNK-sEV in tumors of xenografted murine models. Notably, elevated containment of granulysin (GNLY) within mNK-sEV, at least in part, may contribute to the enhanced therapeutic effect. Herein our results present that mNK-sEV can be a novel class of therapeutic reagent for effective cancer treatment.

Exosome-based anticancer vaccines: From Bench to bedside

Exosomes, a subset of extracellular vesicles, are released by all active cells and play a crucial role in intercellular communications. Exosomes could facilitate the transfer of various biologically active molecules, such as DNA, non-coding RNAs, and proteins, from donor to recipient cells, thereby participating in diverse biological and pathological processes. Besides, exosomes possess unique characteristics, including non-toxicity, low-immunogenicity, and stability within biological systems, rendering them highly advantageous for cancer drug development. Meanwhile, accumulating evidence suggests that exosomes originating from tumor cells and immune cells possess distinct composition profiles that play a direct role in anticancer immunotherapy. Of note, exosomes can transport their contents to specific cells, thereby exerting an impact on the phenotype and immune-regulatory functions of targeted cells. Therapeutic cancer vaccines, an emerging therapeutics of immunotherapy, could enhance antitumor immune responses by delivering a large number of tumor antigens, thereby augmenting the immune response against tumor cells. Therefore, the therapeutic rationale of cancer vaccines and exosome-based immunotherapy are almost similar to some extent, but some challenges have hindered their application in the clinical setting. Here, in this review, we first summarized the biogenesis, structure, compositions, and biological functions of exosomes. Then we described the roles of exosomes in cancer biology, particularly in tumor immunity. We also comprehensively reviewed current exosome-based anticancer vaccine development and we divided them into three types. Finally, we give some insights into clinical translation and clinical trial progress of exosome-based anticancer vaccines for future direction.

AML cell-derived exosomes suppress the activation and cytotoxicity of NK cells in AML via PD-1/PD-L1 pathway

Exosomes are bilayer lipid bodies and contain a variety of bioactive molecules such as proteins, lipids, and nucleic acids, and so forth. Exosomes derived from solid tumors may play critical roles in tumor development and immune evasion. However, the underlying effects of tumor-derived exosomes on immune function in modulating intercellular crosstalk within the bone marrow niche during acute myeloid leukemia (AML) development and immune evasion remain largely elusive. In this study, we aimed to explore the role of AML-exos in AML immune evasion. First, we isolated tumor-derived exosomes from AML cells (AML-exos) and revealed the presence of programmed cell death ligand-1 (PD-L1) protein in AML-exos. Next, we demonstrated that AML-exos can directly suppress the activation of natural killer (NK) cells and inhibit the cytotoxicity of NK cells, probably through activating the programmed cell death-1 (PD-1)/PD-L1 pathway. Furthermore, the inhibitory effect of AML-exos on NK cells could be alleviated by either PD-L1 inhibitor or antagonist. In summary, we demonstrated that AML-exos possess a PD-L1-dependent tumor-promoting effect which may contribute to immune tolerance in antitumor therapy, but blocking the PD-1/PD-L1 pathway may alleviate the tumor immunosuppression induced by AML-exos. Our findings in this study may offer a new immunotherapy strategy to cure AML.

Feline coronavirus influences the biogenesis and composition of extracellular vesicles derived from CRFK cells

Introduction

Coronavirus (CoV) has become a public health crisis that causes numerous illnesses in humans and certain animals. Studies have identified the small, lipid-bound structures called extracellular vesicles (EVs) as the mechanism through which viruses can enter host cells, spread, and evade the host's immune defenses. EVs are able to package and carry numerous viral compounds, including proteins, genetic substances, lipids, and receptor proteins. We proposed that the coronavirus could alter EV production and content, as well as influence EV biogenesis and composition in host cells.

Methods

In the current research, Crandell-Rees feline kidney (CRFK) cells were infected with feline coronavirus (FCoV) in an exosome-free media at a multiplicity of infection (MOI) of 2,500 infectious units (IFU) at 48 h and 72 h time points. Cell viability was analyzed and found to be significantly decreased by 9% (48 h) and 15% (72 h) due to FCoV infection. EVs were isolated by ultracentrifugation, and the surface morphology of isolated EVs was analyzed via Scanning Electron Microscope (SEM).

Results

NanoSight particle tracking analysis (NTA) confirmed that the mean particle sizes of control EVs were 131.9 nm and 126.6 nm, while FCoV infected-derived EVs were 143.4 nm and 120.9 nm at 48 and 72 h, respectively. Total DNA, RNA, and protein levels were determined in isolated EVs at both incubation time points; however, total protein was significantly increased at 48 h. Expression of specific protein markers such as TMPRSS2, ACE2, Alix, TSG101, CDs (29, 47, 63), TLRs (3, 6, 7), TNF-α, and others were altered in infection-derived EVs when compared to control-derived EVs after FCoV infection.

Discussion

Our findings suggested that FCoV infection could alter the EV production and composition in host cells, which affects the infection progression and disease evolution. One purpose of studying EVs in various animal coronaviruses that are in close contact with humans is to provide significant information about disease development, transmission, and adaptation. Hence, this study suggests that EVs could provide diagnostic and therapeutic applications in animal CoVs, and such understanding could provide information to prevent future coronavirus outbreaks.

Integration of photomagnetic bimodal imaging to monitor an autogenous exosome loaded platform: unveiling strong targeted retention effects for guiding the photothermal and magnetothermal therapy in a mouse prostate cancer model

BACKGROUND

Prostate cancer (PCa) is the most prevalent cancer among males, emphasizing the critical need for precise diagnosis and treatment to enhance patient prognosis. Recent studies have extensively utilized urine exosomes from patients with cancer for targeted delivery. This study aimed to employ highly sensitive magnetic particle imaging (MPI) and fluorescence molecular imaging (FMI) to monitor the targeted delivery of an exosome-loaded platform at the tumour site, offering insights into a potential combined photothermal and magnetic thermal therapy regime for PCa.

RESULTS

MPI and FMI were utilized to monitor the in vivo retention performance of exosomes in a prostate tumour mouse model. The exosome-loaded platform exhibited robust homologous targeting ability during imaging (SPIONs@EXO-Dye:66·48%±3·85%; Dye-SPIONs: 34·57%±7·55%, **P<0·01), as verified by in vitro imaging and in vitro tissue Prussian blue staining.

CONCLUSIONS

The experimental data underscore the feasibility of using MPI for in vivo PCa imaging. Furthermore, the exosome-loaded platform may contribute to the precise diagnosis and treatment of PCa.

The diagnostic value of serum exosomal SNORD116 and SNORA21 for NSCLC patients

PURPOSE

Non-small cell lung cancer (NSCLC) is a widespread and serious global malignancy. This study aimed to examine the clinical relevance of serum exosomal SNORD116 and SNORA21 as novel diagnostic biomarkers for NSCLC.

METHODS

Serum exosomes from 226 healthy controls and 305 NSCLC patients were isolated by ultracentrifugation. Characterization of exosomes was conducted by qNano, transmission electron microscopy (TEM) and Western immunoblotting. RT-PCR revealed snoRNAs that were differentially expressed. Receiver operating characteristic (ROC) analysis was used to assess the diagnostic performance.

RESULTS

In NSCLC patients, the levels of serum exosomal SNORD116 and SNORA21 were significantly reduced compared to those in healthy controls (P < 0.0001 for both). ROC curves showed AUC values of 0.738 and 0.761. By combining SNORD116 and SNORA21 with traditional blood biomarkers CYFRA21-1 and carcinoembryonic antigen (CEA), the AUC increased to 0.917. Moreover, these two exosomal snoRNAs distinguished between patients with metastatic NSCLC (n = 132) and those with non-metastatic NSCLC (n = 173) significantly (P < 0.0001 for both). The ROC curves gave AUC values of 0.743 and 0.694, respectively. The combined analysis raised the AUC to 0.751. The diagnostic power of these two exosomal snoRNAs combined with CYFRA21-1 and CEA increased to 0.784.

CONCLUSION

This study demonstrated that serum exosomal SNORD116 and SNORA21 can be used as potential promising non-invasive diagnostic biomarkers for NSCLC.

Regulation of the PD-1/PD-L1 Axis and NK Cell Dysfunction by Exosomal miR-552-5p in Gastric Cancer

OBJECTIVE

NK cells play a vital role in tumor immune resistance. Various factors affect NK cell activity. While NK cell dysfunction has been observed in numerous malignancies, the underlying mechanisms in gastric cancer remain unclear.

METHOD

Flow cytometry was used to identify the phenotypic distribution and expression of activated receptors on NK cells. ELISA was used to determine the expression of cytokines. We examined the expression of NK cell-related genes and explored their association with survival and prognosis. Additionally, we conducted PCR detection of miR-552-5p expression levels in plasma exosomes of patients and investigated its correlation with phenotypic distribution and activated receptors. We used flow cytometry and ELISA to verify the role of miR-552-5p in NK cell dysfunction. Furthermore, we investigated the potential role of PD-1/PD-L1 in regulating NK cell dysfunction in patients' cells.

RESULTS

We observed a significant decrease in the percentage of NKG2D and NKp30 and IFN-γ and TNF-α in patients than in healthy volunteers. Patients with low levels of CD56, CD16, NKG2D, and NKP46 exhibited poorer survival prognoses. Moreover, increased expression levels of plasma exosomal miR-552-5p in patients were negatively associated with NK cell phenotypic distribution and activated receptor expression. MiR-552-5p downregulated the secretion of perforin, granzyme, and IFN-γ as well as the expression of NKp30, NKp46, and NKG2D. Additionally, it suppressed the cytotoxicity of NK cells. The inhibitory effect of miR-552-5p, on NK cell function was reversed when anti-PD-L1 antibodies were used.

CONCLUSION

Exosomal miR-552-5p targets the PD-1/PD-L1 axis, leading to impaired NK cell function.

Bioengineered mesenchymal stem cell-derived exosomes: emerging strategies for diabetic wound healing

Diabetic wounds are among the most common complications of diabetes mellitus and their healing process can be delayed due to persistent inflammatory reactions, bacterial infections, damaged vascularization and impaired cell proliferation, which casts a blight on patients'health and quality of life. Therefore, new strategies to accelerate diabetic wound healing are being positively explored. Exosomes derived from mesenchymal stem cells (MSC-Exos) can inherit the therapeutic and reparative abilities of stem cells and play a crucial role in diabetic wound healing. However, poor targeting, low concentrations of therapeutic molecules, easy removal from wounds and limited yield of MSC-Exos are challenging for clinical applications. Bioengineering techniques have recently gained attention for their ability to enhance the efficacy and yield of MSC-Exos. In this review, we summarise the role of MSC-Exos in diabetic wound healing and focus on three bioengineering strategies, namely, parental MSC-Exos engineering, direct MSC-Exos engineering and MSC-Exos combined with biomaterials. Furthermore, the application of bioengineered MSC-Exos in diabetic wound healing is reviewed. Finally, we discuss the future prospects of bioengineered MSC-Exos, providing new insights into the exploration of therapeutic strategies.

Extracellular Vesicles, Circadian Rhythms, and Cancer: A Comprehensive Review with Emphasis on Hepatocellular Carcinoma

This review comprehensively explores the complex interplay between extracellular vesicles (ECVs)/exosomes and circadian rhythms, with a focus on the role of this interaction in hepatocellular carcinoma (HCC). Exosomes are nanovesicles derived from cells that facilitate intercellular communication by transporting bioactive molecules such as proteins, lipids, and RNA/DNA species. ECVs are implicated in a range of diseases, where they play crucial roles in signaling between cells and their surrounding environment. In the setting of cancer, ECVs are known to influence cancer initiation and progression. The scope of this review extends to all cancer types, synthesizing existing knowledge on the various roles of ECVs. A unique aspect of this review is the emphasis on the circadian-controlled release and composition of exosomes, highlighting their potential as biomarkers for early cancer detection and monitoring metastasis. We also discuss how circadian rhythms affect multiple cancer-related pathways, proposing that disruptions in the circadian clock can alter tumor development and treatment response. Additionally, this review delves into the influence of circadian clock components on ECV biogenesis and their impact on reshaping the tumor microenvironment, a key component driving HCC progression. Finally, we address the potential clinical applications of ECVs, particularly their use as diagnostic tools and drug delivery vehicles, while considering the challenges associated with clinical implementation.

Isolation and Characterization of Milk Exosomes for Use in Advanced Therapies

Exosomes are cell-derived extracellular vesicles (EVs) with diameters between 30 and 120 nm. In recent years, several studies have evaluated the therapeutic potential of exosomes derived from different fluids due to their low immunogenicity and high biocompatibility. However, producing exosomes on a large scale is still challenging. One of the fluids from which they could be isolated in large quantities is milk. Moreover, regeneration is a well-known property of milk. The present work seeks to optimize a method for isolating exosomes from bovine and human milk, comparing different storage conditions and different extraction protocols. We found differences in the yield extraction associated with pre-storage milk conditions and observed some differences according to the processing agent. When we removed milk fat globules and added rennet before freezing, we obtained a cleaner final fraction. In summary, we attempted to optimize a rennet-based new milk-exosome isolation method and concluded that pre-treatment, followed by freezing of samples, yielded the best exosome population.

Exosomes based strategies for cardiovascular diseases: Opportunities and challenges

Exosomes, as nanoscale extracellular vesicles (EVs), are secreted by all types of cells to facilitate intercellular communication in living organisms. After being taken up by neighboring or distant cells, exosomes can alter the expression levels of target genes in recipient cells and thereby affect their pathophysiological outcomes depending on payloads encapsulated therein. The functions and mechanisms of exosomes in cardiovascular diseases have attracted much attention in recent years and are thought to have cardioprotective and regenerative potential. This review summarizes the biogenesis and molecular contents of exosomes and details the roles played by exosomes released from various cells in the progression and recovery of cardiovascular disease. The review also discusses the current status of traditional exosomes in cardiovascular tissue engineering and regenerative medicine, pointing out several limitations in their application. It emphasizes that some of the existing emerging industrial or bioengineering technologies are promising to compensate for these shortcomings, and the combined application of exosomes and biomaterials provides an opportunity for mutual enhancement of their performance. The integration of exosome-based cell-free diagnostic and therapeutic options will contribute to the further development of cardiovascular regenerative medicine.

Harnessing tumor-derived exosomes: A promising approach for the expansion of clinical diagnosis, prognosis, and therapeutic outcome of prostate cancer

Prostate cancer is the second leading cause of men's death worldwide. Although early diagnosis and therapy for localized prostate cancer have improved, the majority of men with metastatic disease die from prostate cancer annually. Therefore, identification of the cellular-molecular mechanisms underlying the progression of prostate cancer is essential for overcoming controlled proliferation, invasion, and metastasis. Exosomes are small extracellular vesicles that mediate most cells' interactions and contain membrane proteins, cytosolic and nuclear proteins, extracellular matrix proteins, lipids, metabolites, and nucleic acids. Exosomes play an essential role in paracrine pathways, potentially influencing Prostate cancer progression through a wide variety of mechanisms. In the present review, we outline and discuss recent progress in our understanding of the role of exosomes in the Prostate cancer microenvironment, like their involvement in prostate cancer occurrence, progression, angiogenesis, epithelial-mesenchymal transition, metastasis, and drug resistance. We also present the latest findings regarding the function of exosomes as biomarkers, direct therapeutic targets in prostate cancer, and the challenges and advantages associated with using exosomes as natural carriers and in exosome-based immunotherapy. These findings are a promising avenue for the expansion of potential clinical approaches.

Novel Personalized Cancer Vaccine Using Tumor Extracellular Vesicles with Attenuated Tumorigenicity and Enhanced Immunogenicity

Cancer vaccines offer a promising avenue in cancer immunotherapy by inducing systemic, tumor-specific immune responses. Tumor extracellular vesicles (TEVs) are nanoparticles naturally laden with tumor antigens, making them appealing for vaccine development. However, their inherent malignant properties from the original tumor cells limit their direct therapeutic use. This study introduces a novel approach to repurpose TEVs as potent personalized cancer vaccines. The study shows that inhibition of both YAP and autophagy not only diminishes the malignancy-associated traits of TEVs but also enhances their immunogenic attributes by enriching their load of tumor antigens and adjuvants. These revamped TEVs, termed attenuated yet immunogenically potentiated TEVs (AI-TEVs), showcase potential in inhibiting tumor growth, both as a preventive measure and a possible treatment for recurrent cancers. They prompt a tumor-specific and enduring immune memory. In addition, by showing that AI-TEVs can counteract cancer growth in a personalized vaccine approach, a potential strategy is presented for developing postoperative cancer immunotherapy that's enduring and tailored to individual patients.

The role of extracellular vesicles in immune cell exhaustion and resistance to immunotherapy

INTRODUCTION

Extracellular vesicles (EVs) are membrane-bound nanoparticles for intercellular communication. Subtypes of EVs, namely exosomes and microvesicles transfer diverse, bioactive cargo to their target cells and eventually interfere with immune responses. Despite being a promising approach, cancer immunotherapy currently faces several challenges including immune resistance. EVs secreted from various sources in the tumor microenvironment provoke immune cell exhaustion and lower the efficacy of immunological treatments, such as CAR T cells and immune checkpoint inhibitors.

AREAS COVERED

This article goes through the mechanisms of action of various types of EVs in inhibiting immune response and immunotherapies, and provides a comprehensive review of EV-based treatments.

EXPERT OPINION

By making use of the distinctive features of EVs, natural or modified EVs are innovatively utilized as novel cancer therapeutics. They are occasionally coupled with currently established treatments to overcome their inadequacies. Investigating the properties and interactions of EVs and EV-based treatments is crucial for determining future steps in cancer therapeutics.

Epigenetic regulation of autophagy by non-coding RNAs and exosomal non-coding RNAs in colorectal cancer: A narrative review

One of the major diseases affecting people globally is colorectal cancer (CRC), which is primarily caused by a lack of effective medical treatment and a limited understanding of its underlying mechanisms. Cellular autophagy functions to break down and eliminate superfluous proteins and substances, thereby facilitating the continual replacement of cellular elements and generating vital energy for cell processes. Non-coding RNAs and exosomal ncRNAs have a crucial impact on regulating gene expression and essential cellular functions such as autophagy, metastasis, and treatment resistance. The latest research has indicated that specific ncRNAs and exosomal ncRNA to influence the process of autophagy in CRC cells, which could have significant consequences for the advancement and treatment of this disease. It has been determined that a variety of ncRNAs have a vital function in regulating the genes essential for the formation and maturation of autophagosomes. Furthermore, it has been confirmed that ncRNAs have a considerable influence on the signaling pathways associated with autophagy, such as those involving AMPK, AKT, and mTOR. Additionally, numerous ncRNAs have the potential to affect specific genes involved in autophagy. This study delves into the control mechanisms of ncRNAs and exosomal ncRNAs and examines how they simultaneously influence autophagy in CRC.

Exosomal IGFBP2 derived from highly metastatic promotes hepatocellular carcinoma metastasis by inducing epithelial mesenchymal transition

Liver cancer metastasis is the main cause of death in liver cancer patients. Exosomes, which are small vesicles released by cancer cells, play a crucial role in the metastasis of cancer. The aim of this study was to investigate the effect of exosomes derived from high metastatic potential liver cancer cells acting as cell to cell communication on liver cancer metastasis. Bioinformatics analysis was used to obtain the differential expression of exosomal mRNAs from the plasma of both liver cancer patients and healthy volunteers. Transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA), and protein blot were employed to characterize the exosomes. The molecular mechanisms and were explored by conducting CCK8, Transwell, Tunel, RTqPCR, western blot, and immunofluorescence staining. We examined IGFBP2 special expression in the plasma exosomes of both liver cancer patients and healthy volunteers, and its presence was associated with a poor prognosis in liver cancer patients. Furthermore, we observed that exosomes from highly metastatic liver cancer cells (MHCC97H) contained high levels of IGFBP2 and could enhance the metastatic potential of less aggressive liver cancer cells (Hep3B). Additionally, we discovered that IGFBP2 in MHCC97H-derived exosomes activated ERK signaling pathway, which triggered epithelial-mesenchymal transition (EMT) in Hep3B cells. Our study underscores the significance of exosomal IGFBP2 from highly metastatic liver cancer cells as a driver of metastasis in less invasive liver cancer cells. This suggests that targeting IGFBP2 in exosomes could be a promising strategy for the treatment and prognosis of liver cancer patients.

Natural killer cell-derived exosome-based cancer therapy: from biological roles to clinical significance and implications

Natural killer (NK) cells are important immune cells in the organism and are the third major type of lymphocytes besides T cells and B cells, which play an important function in cancer therapy. In addition to retaining the tumor cell killing function of natural killer cells, natural killer cell-derived exosomes cells also have the characteristics of high safety, wide source, easy to preserve and transport. At the same time, natural killer cell-derived exosomes are easy to modify, and the engineered exosomes can be used in combination with a variety of current cancer therapies, which not only enhances the therapeutic efficacy, but also significantly reduces the side effects. Therefore, this review summarizes the source, isolation and modification strategies of natural killer cell-derived exosomes and the combined application of natural killer cell-derived engineered exosomes with other antitumor therapies, which is expected to accelerate the clinical translation process of natural killer cell-derived engineered exosomes in cancer therapy.

Netrin-1-engineered endothelial cell exosomes induce the formation of pre-regenerative niche to accelerate peripheral nerve repair

The formation of vascular niche is pivotal during the early stage of peripheral nerve regeneration. Nevertheless, the mechanisms of vascular niche in the regulation of peripheral nerve repair remain unclear. Netrin-1 (NTN1) was found up-regulated in nerve stump after peripheral nerve injury (PNI). Herein, we demonstrated that NTN1-high endothelial cells (NTN1+ECs) were the critical component of vascular niche, fostering angiogenesis, axon regeneration, and repair-related phenotypes. We also found that NTN1+EC-derived exosomes (NTN1 EC-EXO) were involved in the formation of vascular niche as a critical role. Multi-omics analysis further verified that NTN1 EC-EXO carried a low-level expression of let7a-5p and activated key pathways associated with niche formation including focal adhesion, axon guidance, phosphatidylinositol 3-kinase-AKT, and mammalian target of rapamycin signaling pathway. Together, our study suggested that the construction of a pre-regenerative niche induced by NTN1 EC-EXO could establish a beneficial microenvironment for nerve repair and facilitate functional recovery after PNI.

Prospects and challenges of tissue-derived extracellular vesicles

Extracellular vesicles (EVs) are considered a vital component of cell-to-cell communication and represent a new frontier in diagnostics and a means to identify pathways for therapeutic intervention. Recently, studies have revealed the importance of tissue-derived EVs (Ti-EVs), which are EVs present in the interstitial spaces between cells, as they better represent the underlying physiology of complex, multicellular tissue microenvironments in biology and disease. EVs are native, lipid bilayer membraned nano-sized particles produced by all cells that are packaged with varied functional biomolecules including proteins, lipids, and nucleic acids. They are implicated in short- and long-range cellular communication and may elicit functional responses in recipient cells. To date, studies have often utilized cultured cells or biological fluids as a source for EVs that do not capture local molecular signatures of the tissue microenvironment. Recent work utilizing Ti-EVs has elucidated novel biomarkers for disease and provided insights into disease mechanisms that may lead to the development of novel therapeutic agents. Still, there are considerable challenges facing current studies. This review explores the vast potential and unique challenges for Ti-EV research and provides considerations for future studies that seek to advance this exciting field.

Harnessing exosomes and plant-derived exosomes as nanocarriers for the efficient delivery of plant bioactives

Exosomes, a category of extracellular vesicle (EV), are phospholipid bilayer structures ranging from 30 to 150 nm, produced by various organisms through the endosomal pathway. Recent studies have established the utilization of exosomes as nanocarriers for drug distribution across various therapeutic areas including cancer, acute liver injury, neuroprotection, oxidative stress, inflammation, etc. The importance of plant-derived exosomes and exosome vesicles derived from mammalian cells or milk, loaded with potent plant bioactives for various therapeutic indications are discussed along with insights into future perspectives. Moreover, this review provides a detailed understanding of exosome biogenesis, their composition, classification, stability of different types of exosomes, and different routes of administration along with the standard techniques used for isolating, purifying, and characterizing exosomes.

Modulatory effects of cancer stem cell-derived extracellular vesicles on the tumor immune microenvironment

Cancer stem cells (CSCs), accounting for only a minor cell proportion (< 1%) within tumors, have profound implications in tumor initiation, metastasis, recurrence, and treatment resistance due to their inherent ability of self-renewal, multi-lineage differentiation, and tumor-initiating potential. In recent years, accumulating studies indicate that CSCs and tumor immune microenvironment act reciprocally in driving tumor progression and diminishing the efficacy of cancer therapies. Extracellular vesicles (EVs), pivotal mediators of intercellular communications, build indispensable biological connections between CSCs and immune cells. By transferring bioactive molecules, including proteins, nucleic acids, and lipids, EVs can exert mutual influence on both CSCs and immune cells. This interaction plays a significant role in reshaping the tumor immune microenvironment, creating conditions favorable for the sustenance and propagation of CSCs. Deciphering the intricate interplay between CSCs and immune cells would provide valuable insights into the mechanisms of CSCs being more susceptible to immune escape. This review will highlight the EV-mediated communications between CSCs and each immune cell lineage in the tumor microenvironment and explore potential therapeutic opportunities.

Serum extracellular vesicle-derived miR-21-5p and miR-26a-5p as non-invasive diagnostic potential biomarkers for gastric cancer: A preliminary study

PURPOSE

Gastric cancer is the most common malignancy worldwide and is the third leading cause of cancer-related deaths, urgently requiring an early and non-invasive diagnosis. Circulating extracellular vesicles may emerge as promising biomarkers for the rapid diagnosis in a non-invasive manner.

METHODS

Using high-throughput small RNA sequencing, we profiled the small RNA population of serum-derived extracellular vesicles from healthy controls and gastric cancer patients. Differentially expressed microRNAs (miRNAs) were randomly selected and validated by reverse transcription-quantitative real-time polymerase chain reaction. Receiver operating characteristic curves were employed to assess the predictive value of miRNAs for gastric cancer.

RESULTS

In this study, 193 differentially expressed miRNAs were identified, of which 152 were upregulated and 41 were significantly downregulated. Among the differently expressed miRNA, the expression levels of miR-21-5p, miR-26a-5p, and miR-27a-3p were significantly elevated in serum-derived extracellular vesicles of gastric cancer patients. The miR-21-5p and miR-27a-3p were closely correlated with the tumor size. Moreover, the expression levels of serum miR-21-5p and miR-26a-5p were significantly decreased in gastric cancer patients after surgery.

CONCLUSIONS

The present study discovered the potential of serum miR-21-5p and miR-26a-5p as promising candidates for the diagnostic and prognostic markers of gastric cancer.

Mesenchymal stem cell-derived exosomes for management of prostate cancer: An updated view

Prostate cancer represents the second most prevalent form of cancer found in males, and stands as the fifth primary contributor to cancer-induced mortality on a global scale. Research has shown that transplanted mesenchymal stem cells (MSCs) can migrate by homing to tumor sites in the body. In prostate cancer, researchers have explored the fact that MSC-based therapies (including genetically modified delivery vehicles or vectors) and MSC-derived exosomes are emerging as attractive options to improve the efficacy and safety of traditional cancer therapies. In addition, researchers have reported new insights into the application of extracellular vesicle (EV)-MSC therapy as a novel treatment option that could provide a more effective and targeted approach to prostate cancer treatment. Moreover, the new generation of exosomes, which contain biologically functional molecules as signal transducers between cells, can simultaneously deliver different therapeutic agents and induce an anti-tumor phenotype in immune cells and their recruitment to the tumor site. The results of the current research on the use of MSCs in the treatment of prostate cancer may be helpful to researchers and clinicians working in this field. Nevertheless, it is crucial to emphasize that although dual-role MSCs show promise as a therapeutic modality for managing prostate cancer, further investigation is imperative to comprehensively grasp their safety and effectiveness. Ongoing clinical trials are being conducted to assess the viability of MSCs in the management of prostate cancer. The results of these trials will help determine the viability of this approach. Based on the current literature, engineered MSCs-EV offer great potential for application in targeted tumor therapy.

Shaping the immune-suppressive microenvironment on tumor-associated myeloid cells through tumor-derived exosomes

Tumor-associated myeloid cells (TAMCs) play a crucial role in orchestrating the dynamics of the tumor immune microenvironment. This heterogeneous population encompasses myeloid-derived suppressor cells, tumor-associated macrophages and dendritic cells, all of which contribute to the establishment of an immunosuppressive milieu that fosters tumor progression. Tumor-derived exosomes (TEXs), small extracellular vesicles secreted by tumor cells, have emerged as central mediators in intercellular communication within the tumor microenvironment. In this comprehensive review, we explore the intricate mechanisms through which TEXs modulate immune-suppressive effects on TAMCs and their profound implications in cancer progression. We delve into the multifaceted ways in which TEXs influence TAMC functions, subsequently affecting tumor immune evasion. Furthermore, we elucidate various therapeutic strategies aimed at targeting TEX-mediated immune suppression, with the ultimate goal of bolstering antitumor immunity.

Extracellular Vesicle Preparation and Analysis: A State-of-the-Art Review

In recent decades, research on Extracellular Vesicles (EVs) has gained prominence in the life sciences due to their critical roles in both health and disease states, offering promising applications in disease diagnosis, drug delivery, and therapy. However, their inherent heterogeneity and complex origins pose significant challenges to their preparation, analysis, and subsequent clinical application. This review is structured to provide an overview of the biogenesis, composition, and various sources of EVs, thereby laying the groundwork for a detailed discussion of contemporary techniques for their preparation and analysis. Particular focus is given to state-of-the-art technologies that employ both microfluidic and non-microfluidic platforms for EV processing. Furthermore, this discourse extends into innovative approaches that incorporate artificial intelligence and cutting-edge electrochemical sensors, with a particular emphasis on single EV analysis. This review proposes current challenges and outlines prospective avenues for future research. The objective is to motivate researchers to innovate and expand methods for the preparation and analysis of EVs, fully unlocking their biomedical potential.

Recent advances in the use of extracellular vesicles from adipose-derived stem cells for regenerative medical therapeutics

Adipose-derived stem cells (ADSCs) are a subset of mesenchymal stem cells (MSCs) isolated from adipose tissue. They possess remarkable properties, including multipotency, self-renewal, and easy clinical availability. ADSCs are also capable of promoting tissue regeneration through the secretion of various cytokines, factors, and extracellular vesicles (EVs). ADSC-derived EVs (ADSC-EVs) act as intercellular signaling mediators that encapsulate a range of biomolecules. These EVs have been found to mediate the therapeutic activities of donor cells by promoting the proliferation and migration of effector cells, facilitating angiogenesis, modulating immunity, and performing other specific functions in different tissues. Compared to the donor cells themselves, ADSC-EVs offer advantages such as fewer safety concerns and more convenient transportation and storage for clinical application. As a result, these EVs have received significant attention as cell-free therapeutic agents with potential future application in regenerative medicine. In this review, we focus on recent research progress regarding regenerative medical use of ADSC-EVs across various medical conditions, including wound healing, chronic limb ischemia, angiogenesis, myocardial infarction, diabetic nephropathy, fat graft survival, bone regeneration, cartilage regeneration, tendinopathy and tendon healing, peripheral nerve regeneration, and acute lung injury, among others. We also discuss the underlying mechanisms responsible for inducing these therapeutic effects. We believe that deciphering the biological properties, therapeutic effects, and underlying mechanisms associated with ADSC-EVs will provide a foundation for developing a novel therapeutic approach in regenerative medicine.

M2 Macrophage-Derived Exosomes Regulate miR-199a-3p Promoter Methylation Through the LINC00470-Mediated myc/DNMT3a Axis to Promote Breast Cancer Development

Breast cancer (BC) is the most common invasive cancer in women. M2 macrophage exosomes promote cancer development and play multiple roles in the tumor microenvironment, but the mechanism of action by which M2 macrophage exosomes promote BC remains unclear. Therefore, the purpose of this study was to investigate the mechanism by which M2 macrophage-derived exosomes promote the development of breast cancer. We collected BC tissues and determined the expression of LINC00470, followed by the establishment of M2 macrophages in culture and the isolation and identification of M2 macrophage exosomes. Next, we investigated the effects of M2 macrophage exosomes on BC cell proliferation, invasion, miR-199a-3p promoter methylation, and the expression of LINC00470, myc, DNMT3A, and miR-199a-3p. Finally, LINC00470 expression was inhibited in M2 macrophage exosomes, while miR-199a-3p expression was inhibited in BC cells, and changes in BC cell proliferation, invasion, miR-199a-3p promoter methylation, and the expression of LINC00470, myc, DNMT3A, and miR-199a-3p were analyzed. We demonstrated that LINC00470 was highly expressed in BC tissues, M2-type macrophages were successfully induced in vitro, and Dil-labeled M2 macrophage exosomes could successfully enter MDA-MB-231 and MCF-7 cells. Coculture of M2 macrophage exosomes with MDA-MB-231 and MCF-7 cells significantly enhanced the proliferation and invasion of MDA-MB-231 and MCF-7 cells, upregulated the expression of LINC00470, myc, and DNMT3A and downregulated the expression of miR-199a-3p. Moreover, the inhibition of LINC00470 expression in M2 macrophage exosomes significantly downregulated the expression of LINC00470, myc, and DNMT3A in MDA-MB-231 and MCF-7 cells, upregulated the expression of miR-199a-3p, and hypomethylated the promoter of the miR-199a-3p locus. Moreover, inhibition of LINC00470 expression in M2 macrophage-derived exosomes significantly attenuated the proliferation and invasive ability of MDA-MB-231 and MCF-7 cells, while miR-199a-3p inhibitor transfection reversed this effect. Collectively, these findings indicated that M2-type macrophage-derived exosomes promote BC proliferation and migration by regulating miR-199a-3p promoter methylation through the LINC00470-mediated myc/DNMT3a axis.

Hypoxic Exosomal circPLEKHM1-Mediated Crosstalk between Tumor Cells and Macrophages Drives Lung Cancer Metastasis

Intercellular communication often relies on exosomes as messengers and is critical for cancer metastasis in hypoxic tumor microenvironment. Some circular RNAs (circRNAs) are enriched in cancer cell-derived exosomes, but little is known about their ability to regulate intercellular communication and cancer metastasis. Here, by systematically analyzing exosomes secreted by non-small cell lung cancer (NSCLC) cells, a hypoxia-induced exosomal circPLEKHM1 is identified that drives NSCLC metastasis through polarizing macrophages toward to M2 type. Mechanistically, exosomal circPLEKHM1 promoted PABPC1-eIF4G interaction to facilitate the translation of the oncostatin M receptor (OSMR), thereby promoting macrophage polarization for cancer metastasis. Importantly, circPLEKHM1-targeted therapy significantly reduces NSCLC metastasis in vivo. circPLEKHM1 serves as a prognostic biomarker for metastasis and poor survival in NSCLC patients. This study unveils a new circRNA-mediated mechanism underlying how cancer cells crosstalk with macrophages within the hypoxic tumor microenvironment to promote metastasis, highlighting the importance of exosomal circPLEKHM1 as a prognostic biomarker and therapeutic target for lung cancer metastasis.

Current knowledge on therapeutic, diagnostic, and prognostics applications of exosomes in multiple myeloma: Opportunities and challenges

Interactions between the plasma cells and the BM microenvironment of Multiple myeloma (MM) take place through factors such as exosomes. Many studies have confirmed the role of exosomes in these interactions. By carrying proteins, cytokines, lipids, microRNAs, etc. as their cargo, exosomes can regulate the interactions between MM plasma cells and neighboring cells and participate in the signaling between cancer cells and the environment. It has been shown that MM-derived exosomes can induce angiogenesis, enhance osteoblast activity, confer drug resistance, and have immunosuppressive properties. Abnormal cargos in endosomes originating from MM patients, can be used as a cancer biomarker to detect or screen early prognosis in MM patients. The native nanostructure of exosomes, in addition to their biocompatibility, stability, and safety, make them excellent candidates for therapeutic, drug delivery, and immunomodulatory applications against MM. On the other hand, exosomes derived from dendritic cells (DC) may be used as vaccines against MM. Thanks to the development of new 'omics' approaches, we anticipate to hear more about exosomes in fight against MM. In the present review, we described the most current knowledge on the role of exosomes in MM pathogenesis and their potential role as novel biomarkers and therapeutic tools in MM.

Immune capture and protein profiling of small extracellular vesicles from human plasma

Extracellular vesicles (EVs), the key players in inter-cellular communication, are produced by all cell types and are present in all body fluids. Analysis of the proteome content is an important approach in structural and functional studies of these vesicles. EVs circulating in human plasma are heterogeneous in size, cellular origin, and functions. This heterogeneity and the potential presence of contamination with plasma components such as lipoprotein particles and soluble plasma proteins represent a challenge in profiling the proteome of EV subsets by mass spectrometry. An immunocapture strategy prior to mass spectrometry may be used to isolate a homogeneous subpopulation of small EVs (sEV) with a specific endocytic origin from plasma or other biofluids. Immunocapture selectively separates EV subpopulations in biofluids based on the presence of a unique protein carried on the vesicle surface. The advantages and disadvantages of EV immune capture as a preparative step for mass spectrometry are discussed.

Exosomal lncRNA-MIAT promotes neovascularization via the miR-133a-3p/MMP-X1 axis in diabetic retinopathy

Diabetic retinopathy (DR), a most common microangiopathy of diabetes, causes vision loss and even blindness. The mechanisms of exosomal lncRNA remain unclear in the development of DR. Here, we first identifed the pro-angiogenic effect of exosomes derived from vitreous humor of proliferative diabetic retinopathy patients, where lncRNA-MIAT was enriched inside. Secondly, lncRNA-MIAT was demonstrated significantly increased in exosomes from high glucose induced human retinal vascular endothelial cell, and can regulate tube formation, migration and proliferation ability to promote angiogenesis in vitro and in vivo. Mechanistically, the pro-angiogenic effect of lncRNA-MIAT was via the lncRNA-MIAT/miR-133a-3p/MMP-X1 axis. The reduced level of lncRNA-MIAT in this axis mitigated the generation of retinal neovascular in mouse model of oxygen-induced retinopathy (OIR), providing crucial evidence for lncRNA-MIAT as a potential clinical target. These findings enhance our understanding of the role of exosomal lncRNA-MIAT in retinal angiogenesis, and propose a promising therapeutic strategy against diabetic retinopathy.

Enhancing cancer therapy: The role of drug delivery systems in STAT3 inhibitor efficacy and safety

The signal transducer and activator of transcription 3 (STAT3), a member of the STAT family, resides in the nucleus to regulate genes essential for vital cellular functions, including survival, proliferation, self-renewal, angiogenesis, and immune response. However, continuous STAT3 activation in tumor cells promotes their initiation, progression, and metastasis, rendering STAT3 pathway inhibitors a promising avenue for cancer therapy. Nonetheless, these inhibitors frequently encounter challenges such as cytotoxicity and suboptimal biocompatibility in clinical trials. A viable strategy to mitigate these issues involves delivering STAT3 inhibitors via drug delivery systems (DDSs). This review delineates the regulatory mechanisms of the STAT3 signaling pathway and its association with cancer. It offers a comprehensive overview of the current application of DDSs for anti-STAT3 inhibitors and investigates the role of DDSs in cancer treatment. The conclusion posits that DDSs for anti-STAT3 inhibitors exhibit enhanced efficacy and reduced adverse effects in tumor therapy compared to anti-STAT3 inhibitors alone. This paper aims to provide an outline of the ongoing research and future prospects of DDSs for STAT3 inhibitors. Additionally, it presents our insights on the merits and future outlook of DDSs in cancer treatment.

Increasing the sensitivity and accuracy of detecting exosomes as biomarkers for cancer monitoring using optical nanobiosensors

The advancement of nanoscience and material design in recent times has facilitated the creation of point-of-care devices for cancer diagnosis and biomolecule sensing. Exosomes (EXOs) facilitate the transfer of bioactive molecules between cancer cells and diverse cells in the local and distant microenvironments, thereby contributing to cancer progression and metastasis. Specifically, EXOs derived from cancer are likely to function as biomarkers for early cancer detection due to the genetic or signaling alterations they transport as payload within the cancer cells of origin. It has been verified that EXOs circulate steadily in bodily secretions and contain a variety of information that indicates the progression of the tumor. However, acquiring molecular information and interactions regarding EXOs has presented significant technical challenges due to their nanoscale nature and high heterogeneity. Colorimetry, surface plasmon resonance (SPR), fluorescence, and Raman scattering are examples of optical techniques utilized to quantify cancer exosomal biomarkers, including lipids, proteins, RNA, and DNA. Many optically active nanoparticles (NPs), predominantly carbon-based, inorganic, organic, and composite-based nanomaterials, have been employed in biosensing technology. The exceptional physical properties exhibited by nanomaterials, including carbon NPs, noble metal NPs, and magnetic NPs, have facilitated significant progress in the development of optical nanobiosensors intended for the detection of EXOs originating from tumors. Following a summary of the biogenesis, biological functions, and biomarker value of known EXOs, this article provides an update on the detection methodologies currently under investigation. In conclusion, we propose some potential enhancements to optical biosensors utilized in detecting EXO, utilizing various NP materials such as silicon NPs, graphene oxide (GO), metal NPs, and quantum dots (QDs).