Exosome regulation of immune response mechanism: Pros and cons in immunotherapy

Due to its multiple features, including the ability to orchestrate remote communication between different tissues, the exosomes are the extracellular vesicles arousing the highest interest in the scientific community. Their size, established as an average of 30-150 nm, allows them to be easily uptaken by most cells. According to the type of cells-derived exosomes, they may carry specific biomolecular cargoes used to reprogram the cells they are interacting with. In certain circumstances, exosomes stimulate the immune response by facilitating or amplifying the release of foreign antigens-killing cells, inflammatory factors, or antibodies (immune activation). Meanwhile, in other cases, they are efficiently used by malignant elements such as cancer cells to mislead the immune recognition mechanism, carrying and transferring their cancerous cargoes to distant healthy cells, thus contributing to antigenic invasion (immune suppression). Exosome dichotomic patterns upon immune system regulation present broad advantages in immunotherapy. Its perfect comprehension, from its early biogenesis to its specific interaction with recipient cells, will promote a significant enhancement of immunotherapy employing molecular biology, nanomedicine, and nanotechnology.

A state-of-the-art review of the recent advances in exosome isolation and detection methods in viral infection

Proteins, RNA, DNA, lipids, and carbohydrates are only some of the molecular components found in exosomes released by tumor cells. They play an essential role in healthy and diseased cells as messengers of short- and long-distance intercellular communication. However, since exosomes are released by every kind of cell and may be found in blood and other bodily fluids, they may one day serve as biomarkers for a wide range of disorders. In many pathological conditions, including cancer, inflammation, and infection, they play a role. It has been shown that the biogenesis of exosomes is analogous to that of viruses and that the exosomal cargo plays an essential role in the propagation, dissemination, and infection of several viruses. Bidirectional modulation of the immune response is achieved by the ability of exosomes associated with viruses to facilitate immunological escape and stimulate the body's antiviral immune response. Recently, exosomes have received a lot of interest due to their potential therapeutic use as biomarkers for viral infections such as human immunodeficiency virus (HIV), Hepatitis B virus (HBV), Hepatitis C virus (HCV), Epstein-Barr virus (EBV), and SARS-CoV-2. This article discusses the purification procedures and detection techniques for exosomes and examines the research on exosomes as a biomarker of viral infection.

The mir-199b-5p encapsulated in adipocyte-derived exosomes mediates radioresistance of colorectal cancer cells by targeting JAG1

Radiotherapy is a key treatment option for colorectal cancer, but its efficacy varies among patients. Our previous studies suggested that adipose tissue may confer the radioresistance of several abdominal tumors, such as pancreatic cancer, biliary cancer, and others. In the present work, the effects of adipocytes in regulating the radiosensitivity of colorectal cancer are explored for the first time. It was found that colony formation was increased and radiation-induced apoptosis decreased in colorectal cancer cells HCT8 and HCT116 co-cultured with adipocytes, which verified the mediation of adipocyte-driven radioresistance in colorectal cancer in vitro. Next, the colorectal cancer cells were incubated with adipocyte-derived exosomes, and a perceptible reduction in radiosensitivity was detected. Furthermore, to investigate the possible mechanisms involved, the exosomes were isolated, the encapsulated microRNAs were extracted and analyzed by small RNA sequencing. Based on bioinformatics analysis and qRT-PCR verification, miR-199b-5p was chosen for functional annotation. It was shown that miR-199b-5p expression was significantly upregulated after 6 Gy irradiation, and overexpressed miR-199b-5p significantly suppressed the radiosensitivity of HCT8 and HCT116 cells. In addition, jagged canonical Notch ligand 1(JAG1) was identified as the target gene of miR-199b-5p by using bioinformatics prediction and dual luciferase reporter gene assay. It was demonstrated that JAG1 conferred the radioresistance of colorectal cancer cells both in vivo and in vitro. Taken together, the present study demonstrates that adipocytes trigger the radioresistance of colorectal cancer cells, probably by targeting JAG1 through an adipocyte-derived exosomal miR-199b-5p.

Exosome subpopulations: The isolation and the functions in diseases

Exosomes are nanoscale extracellular vesicles secreted by cells. Exosomes mediate intercellular communication by releasing their bioactive contents (e.g., DNAs, RNAs, lipids, proteins, and metabolites). The components of exosomes are regulated by the producing cells of exosomes. Due to their diverse origins, exosomes are highly heterogeneous in size, content, and function. Depending on these characteristics, exosomes can be divided into multiple subpopulations which have different functions. Efficient enrichment of specific subpopulations of exosomes helps to investigate their biological functions. Accordingly, numerous techniques have been developed to isolate specific subpopulations of exosomes. This review systematically introduces emerging new technologies for the isolation of different exosome subpopulations and summarizes the critical role of specific exosome subpopulations in diseases, especially in tumor occurrence and progression.

Exosome-based delivery strategies for tumor therapy: an update on modification, loading, and clinical application

Malignancy is a major public health problem and among the leading lethal diseases worldwide. Although the current tumor treatment methods have therapeutic effect to a certain extent, they still have some shortcomings such as poor water solubility, short half-life, local and systemic toxicity. Therefore, how to deliver therapeutic agent so as to realize safe and effective anti-tumor therapy become a problem urgently to be solved in this field. As a medium of information exchange and material transport between cells, exosomes are considered to be a promising drug delivery carrier due to their nano-size, good biocompatibility, natural targeting, and easy modification. In this review, we summarize recent advances in the isolation, identification, drug loading, and modification of exosomes as drug carriers for tumor therapy alongside their application in tumor therapy. Basic knowledge of exosomes, such as their biogenesis, sources, and characterization methods, is also introduced herein. In addition, challenges related to the use of exosomes as drug delivery vehicles are discussed, along with future trends. This review provides a scientific basis for the application of exosome delivery systems in oncological therapy.

Intrathecal injection of human placental mesenchymal stem cells derived exosomes significantly improves functional recovery in spinal cord injured rats

BACKGROUND

Spinal cord injury (SCI) due to lack of restoration of damaged neuronal cells is associated with sensorimotor impairment. This study was focused on using the human placental mesenchymal stem cells- exosome (HPMSCs- Exosomes) in an animal model of severe SCI under myelogram procedure.

METHODS AND RESULTS

Intrathecal injection of exosomes was performed in the acute phase of SCI in female rats. The improved functional recovery of the animals was followed for 6 weeks in control (saline, n = 6) and HPMSCs- EXO (HPMSCs-Exosomes, n = 6) groups. Pathological changes and glial scar size were evaluated. The Immunohistochemistry (IHC) of GFAP and NF200 factors as well as the apoptosis assay was investigated in the tissue samples from the injury site. The results demonstrated that HPMSCs-exosomes can improve motor function by attenuating apoptosis of neurons at the injury site, decreasing GFAP expression and increasing NF200 in the HPMSCs-EXO group. Also, HPMSCs-exosomes by preventing the formation of cavities causes preservation of tissue in SCI rats.

CONCLUSIONS

These findings demonstrate the effectiveness of HPMSC-Exosomes as a therapeutic method to improve functional recovery, reduce pathological changes associated with injury, and prevent chronicity after SCI. The neuroprotective and anti-apoptotic potential of HPMSCs- Exosomes may be a promising therapeutic approach for SCI. Another result was the importance of intrathecal injection of exosomes in the acute phase, which accelerated the healing process. Furthermore, the myelogram can be a feasible and suitable method to confirm the accuracy of intrathecal injection and examine the subarachnoid space in the laboratory animals.

A novel therapeutic strategy: the significance of exosomal miRNAs in acute myeloid leukemia

Acute myeloid leukemia (AML) is a fast-growing blood cancer that interferes with the normal growth of blood cells in the bone marrow and blood. It is characterized by its unpredictable outlook and high death rate. The main treatment for AML is chemotherapy, but this often results in drug resistance and the possibility of the disease returning. For this reason, new biomarkers are necessary to diagnose, predict, and treat this disease. Research has demonstrated that cells responsible for AML release exosomes that interact with the disease's microenvironment. These exosomes have significant roles in promoting leukemia growth, suppressing normal hematopoiesis, facilitating angiogenesis, and contributing to drug resistance in AML. Further investigations have shown that these exosomes contain miRNAs, which are transferred to target cells and have functional roles. Biomarkers are utilized to assess various aspects of tumor cell behavior, including proliferation, apoptosis, angiogenesis, changes in the microenvironment, transfer of drug resistance, and stability in serum and blood plasma. In this research, we showed that exosomal miRNAs and exosomes have the potential to be used as indicators for detecting various phases of AML and can aid in its medical treatment. Furthermore, they can be specifically targeted for therapeutic purposes in addressing this condition.

Spinal Cord Injury: From MicroRNAs to Exosomal MicroRNAs

Spinal cord injury (SCI) is an unfortunate experience that may generate extensive sensory and motor disabilities due to the destruction and passing of nerve cells. MicroRNAs are small RNA molecules that do not code for proteins but instead serve to regulate protein synthesis by targeting messenger RNA's expression. After SCI, secondary damage like apoptosis, oxidative stress, inflammation, and autophagy occurs, and differentially expressed microRNAs show a function in these procedures. Almost all animal and plant cells release exosomes, which are sophisticated formations of lipid membranes. These exosomes have the capacity to deliver significant materials, such as proteins, RNAs and lipids, to cells in need, regulating their functions and serving as a way of communication. This new method offers a fresh approach to treating spinal cord injury. Obviously, the exosome has the benefit of conveying the transported material across performing regulatory activities and the blood-brain barrier. Among the exosome cargoes, microRNAs, which modulate their mRNA targets, show considerable promise in the pathogenic diagnosis, process, and therapy of SCI. Herein, we describe the roles of microRNAs in SCI. Furthermore, we emphasize the importance of exosomal microRNAs in this disease.

Tetraspanin profiles of serum extracellular vesicles reflect functional limitations and pain perception in knee osteoarthritis

BACKGROUND

Emerging evidence suggests that extracellular vesicles (EVs) can play roles in inflammatory processes and joint degradation in primary osteoarthritis (OA), a common age-associated joint disease. EV subpopulations express tetraspanins and platelet markers that may reflect OA pathogenesis. The present study investigated the associations between these EV surface markers and articular cartilage degradation, subjectively and objectively assessed pain, and functional limitations in primary knee OA (KOA).

METHODS

Serum EVs were determined by high-sensitivity flow cytometry (large CD61+ EVs) and single particle interferometric reflectance imaging sensor (small CD41+, CD63+, CD81+, and CD9+ EVs) from end-stage KOA patients and controls (n = 8 per group). Knee pain and physical functions were assessed with several health- and pain-related questionnaires, established measurements of physical medicine, and neuromuscular examination. The obtained data were analyzed using supervised and unsupervised univariate and multivariate models.

RESULTS

With the combined dataset of cartilage thickness, knee function, pain, sensation, and EV molecular signatures, we identified highly correlated groups of variables and found several EV markers that were statistically significant predictors of pain, physical limitations, and other aspects of well-being for KOA patients, for instance CD41+/CD63+/CD9+ small EVs associated with the range of motion of the knee, physical performance, and pain sensitivity.

CONCLUSIONS

Particular serum EV subpopulations showed clear associations with KOA pain and functional limitations, suggesting that their implications in OA pathophysiology warrant further study.

Exosome-Transmitted miR-224-5p Promotes Colorectal Cancer Cell Proliferation via Targeting ULK2 in p53-Dependent Manner

Objective

To investigate the role and molecular mechanism of exosomal miR-224-5p in colorectal cancer (CRC).

Methods

The miR-224-5p expression in CRC patient tissues and cell-derived exosomes was measured by laser capture microdissection and qRT-PCR, respectively. Dual-luciferase reporter gene assay was used to determine the target gene of miR-224-5p. The protein expressions of p53 and unc-51 like kinase 2 (ULK2) in CRC cells were detected by western blot. Flow cytometry was used to detect cell cycle and apoptosis. Cell proliferation was measured by CCK8 and EdU assay.

Results

The miR-224-5p expression was upregulated in CRC tissues and increased progressively with the rise of CRC stage. CRC cells secreted extracellular miR-224-5p mainly in an exosome-dependent manner, and then miR-224-5p could be transferred to surrounding tumor cells to regulate cell proliferation in the form of autocrine or paracrine. Moreover, ULK2 was characterized as a direct target of miR-224-5p and was downregulated in CRC tissues. Interestingly, ULK2 inhibited CRC cell proliferation in a p53-dependent manner. Furthermore, exosome-derived miR-224-5p partially reversed the proliferation regulation of ULK2 on CRC cells.

Conclusion

Our findings demonstrate that exosome-transmitted miR-224-5p promotes p53-dependent cell proliferation by targeting ULK2 in CRC, which may offer promising targets for CRC prevention and therapy.

Exosomes secreted by metastatic cancer cells promotes epithelial mesenchymal transition in small cell lung carcinoma: The key role of Src/TGF-β1 axis

Exosome-mediated epithelial mesenchymal transition (EMT) is key to cancer metastasis. c-Src is involved in the secretion of exosomes and initiation of EMT. Effects of exosomes from metastatic non-small cell lung carcinoma (NSCLC) cells on the EMT process in primary NSCLC cells were assessed. Levels of c-Src in NSCLC tissues were detected and the influence of exosomes from metastatic NSCLC cells on the exosome secretion and EMT process in primary NSCLC cells was assessed. The expression of c-Src was modulated, and the influence on the secretion of exosomes and EMT initiation was evaluated. The level of c-Src was higher in NSCLC specimen and NSCLC cells with promoted EMT process. The suppression of c-Src inhibited secretion of exosomes. Exosomes from metastatic NSCLC cells enhanced migration and invasion abilities of primary NSCLC cells, which had identical effects to c-Src overexpression. The suppression of c-Src inhibited growth and metastasis of solid tumors as well as secretion of exosomes, while the injection of exosomes with c-Src overexpression promoted lung metastasis. TGF-β1 restored the invasion and migration abilities even with c-Src knockdown. The exosomes from metastatic NSCLC cells with high c-Src expression of can increase c-Src level in primary NSCLC cells, contributing to the promoted EMT process through TGF-β1 pathway.

Integrative analysis of serum-derived exosomal lncRNA profiles of alveolar echinococcosis patients

Alveolar echinococcosis is a severe zoonotic disease caused by the pseudotumoral intrahepatic development of the larval stage of the tapeworm Echinococcus multilocularis. The diagnosis of alveolar echinococcosis is hard since it has features of liver cancer. LncRNAs are among the non-coding RNAs that have received the most attention in recent biomarker studies. Here, we aimed to identify the serum-derived exosomal lncRNAs associated with alveolar echinococcosis in humans with RNA-seq. After RNA isolation from exosomes, we performed RNA-seq to determine the lncRNAs. We found 8 target genes in the cis direction and a total of 6468 gene targets for lncRNAs were identified in the trans direction. Totally 621 mRNA transcripts were found as differentially expressed between the controls and patients. 278 of them were up-regulated and 343 were down-regulated. Moreover, 234 lncRNAs were found as differentially expressed between the controls and patients. 58 of them were up-regulated, and 176 of them were down-regulated. The top five biological pathways regulated by identified lncRNAs were detected in this study. As a result, it is thought that these results will contribute to lncRNA-based biomarker studies that can be used in the early diagnosis of alveolar echinococcosis in humans.

How does exosome cause diabetes?

Exosomes are extracellular vesicles that are widely distributed in multiple cell types and circulating body fluids. They have a specific effect on the target cells by releasing different vesicle contents. They have recently been recognized as important means of intercellular communication, being involved, for example, in the development of diabetes by increasing β-cell apoptosis, activating autoimmunity, and regulating cytokines to affect islet β-cell function and insulin sensitivity. An in-depth study of the role of exosome in the pathogenesis of diabetes may therefore provide a novel means of diagnosing and treating diabetes. In this review, we detail how exosome is involved in the development of diabetes.

Exosomal noncoding RNAs as noninvasive biomarkers in bladder cancer: a diagnostic meta-analysis

BACKGROUND

In view of discordance consisting in different reports, a meta-analysis was conducted to comprehensively evaluate the diagnostic efficacy of exosomal noncoding RNAs (ncRNAs) in blood and urine in the detection of bladder cancer.

METHODS

Eligible studies were acquired by systematic retrieval through PubMed, Cochrane Library, and Embase. The pooled diagnostic efficacy was appraised by reckoning the area under the summary receiver operating characteristic (SROC) curve. The latent sources of heterogeneity were probed by subgroup analyses and meta-regression. STATA 12.0, Meta-DiSc 1.4, and RevMan 5.3 were applied to carry out all statistical analyses and plots.

RESULTS

A total of 46 studies from 15 articles comprising 2622 controls and 3015 bladder cancer patients were included in our meta-analysis. Exosomal ncRNAs in blood and urine represented relatively satisfactory diagnostic efficacy in detecting bladder cancer, with a pooled sensitivity of 0.75, a specificity of 0.79, and an area under the SROC curve (AUC) of 0.84. Exosomal microRNAs (miRNAs) exhibited better diagnostic value with a pooled AUC of 0.91 than that of exosomal long noncoding RNAs (lncRNAs). To some extent, the heterogeneity among studies was induced by exosomal ncRNA types (miRNA or lncRNA), exosomal ncRNA profiling (single- or multiple-ncRNA), sample size, specimen types, and ethnicity.

CONCLUSION

Exosomal ncRNAs in blood and urine may play a vital role in diagnosing bladder cancer as prospective noninvasive biomarkers; nonetheless, their clinical performance needs to be confirmed by further massive proactive researches.

Oral cancer cell to endothelial cell communication via exosomal miR-21/RMND5A pathway

Required for meiotic nuclear division 5 homolog A (RMND5A), a novel ubiquitin E3 Ligase, has been reported to correlate with poor prognosis of several cancers. However, its role in endothelial cells has not been reported. In this study, overexpression of RMND5A in human umbilical vein endothelial cells (HUVECs) was performed via lentiviral infection, followed by MTT, would healing and tube formation assay as well as signaling analysis. Moreover, crosstalk between HUVECs and oral squamous cell carcinoma (OSCC) cells was investigated by indirect co-culture with condition medium or tumor cell derived exosomes. Our results showed that overexpression of RMND5A reduced the proliferation, migration and tube formation ability of HUVECs by inhibiting the activation of ERK and NF-κB pathway. Interestingly, OSCC cells can inhibit RMND5A expression of endothelial cells via exosomal miR-21. In summary, our present study unveils that OSCC cells can activate endothelial cells via exosomal miR-21/RMND5A pathway to promote angiogenesis, which may provide novel therapeutic targets for the treatment of OSCC.

M1 macrophage-derived exosome for reprograming M2 macrophages and combining endogenous NO gas therapy with enhanced photodynamic synergistic therapy in colorectal cancer

Reprogramming immunosuppressive M2 macrophages into M1 macrophages in tumor site provides a new strategy for the immunotherapy of colorectal cancer. In this study, M1 macrophage-derived exosome nanoprobe (M1UC) with Ce6-loaded upconversion material is designed to enhance the photodynamic performance of Ce6 while reprogramming M2 macrophages at tumor site and producing NO gas for three-mode synergistic therapy. Under the excitation of near-infrared light at 808 nm, the probe can generate 660 nm up-conversion fluorescence, which enables the photosensitizer Ce6 to produce ROS efficiently. In addition, the probe leads the production of NO by nitric oxide synthase on exosomes. Confocal laser and flow cytometry results show that M1UC probe reprograms M2 macrophages into M1 macrophages with an efficiency of 95.12%. The cell experiments show that the apoptosis rate of the three-mode synergistic therapy group is 78.8%, and the therapeutic effect is significantly higher than those of the other single treatment groups. In vivo experiments results show that M1UC probes maximally gather at the tumor site after 12 h of intravenous injection in orthotopic colorectal cancer mice. After 808 nm laser irradiation, the survival rate of mice is 100% and the recurrence rate was 0 within 60 d, and the therapeutic effect is significantly higher than those of other single treatment groups, which is also confirmed by immunohistochemistry. This M1 macrophage-derived exosome nanoplatform which is based on the three modes of immunotherapy, gas therapy and photodynamic therapy, provides a new design idea for the diagnosis and treatment of deep tumors.

Role of Exosomes in Epithelial-Mesenchymal Transition

Epithelial-mesenchymal transition (EMT) is a fundamental process driving cancer metastasis, transforming non-motile cells into a motile population that migrates to distant organs and forms secondary tumors. In recent years, cancer research has revealed a strong connection between exosomes and the EMT. Exosomes, a subpopulation of extracellular vesicles, facilitate cellular communication and dynamically regulate various aspects of cancer metastasis, including immune cell suppression, extracellular matrix remodeling, metastasis initiation, EMT initiation, and organ-specific metastasis. Tumor-derived exosomes (TEXs) and their molecular cargo, comprising proteins, lipids, nucleic acids, and carbohydrates, are essential components that promote EMT in cancer. TEXs miRNAs play a crucial role in reprogramming the tumor microenvironment, while TEX surface integrins contribute to organ-specific metastasis. Exosome-based cancer metastasis research offers a deeper understanding about cancer and an effective theranostic platform development. Additionally, various therapeutic sources of exosomes are paving the way for innovative cancer treatment development. In this Review, we spotlight the role of exosomes in EMT and their theranostic impact, aiming to inspire cancer researchers worldwide to explore this fascinating field in more innovative ways.

Liquid biopsy in colorectal cancer

Liquid biopsy refers to a set of pathological samples retrieved from non-solid sources, such as blood, cerebrospinal fluid, urine, and saliva through non-invasive or minimally invasive approaches. In the recent decades, an increasing number of studies have focused on clinical applications and improving technological investigation of liquid biopsy biosources for diagnostic goals particularly in cancer. Materials extracted from these sources and used for medical evaluations include cells like circulating tumor cells (CTCs), tumor-educated platelets (TEPs), cell-free nucleic acids released by cells, such as circulating tumor DNA (ctDNA), cell-free DNA (cfDNA), cell-free RNA (cfRNA), and exosomes. Playing significant roles in the pathogenesis of human malignancies, analysis of these sources can provide easier access to genetic and transcriptomic information of the cancer tissue even better than the conventional tissue biopsy. Notably, they can represent the inter- and intra-tumoral heterogeneity and accordingly, liquid biopsies demonstrate strengths for improving diagnosis in early detection and screening, monitoring and follow-up after therapies, and personalization of therapeutical strategies in various types of human malignancies. In this review, we aim to discuss the roles, functions, and analysis approaches of liquid biopsy sources and their clinical implications in human malignancies with a focus on colorectal cancer.

Peptide-graphene logic sensing system for dual-mode detection of exosomes, molecular information processing and protection

Peptides with highly sequence-dependent recognition, assembly, and encoding abilities can perform functions similar to DNA or even better, such as biosensing, molecular information processing, coding, or storage. However, the combination of versatile peptides and 2D materials are rarely used for multipurpose integrated applications, including biosensing, information processing and security. Herein, peptide-graphene sensing system was comprehensively used for dual-signal sensing of tumor-derived exosomes (TDEs), logic computing, and information protection. The system used fluorescent-labeled CD63-binding peptide CP05 and graphene oxide (GO) to selectively detect CD63 and TDEs by fluorescence and resonance light scattering. From three levels such as matter, energy, and information analysis, the matter and energy changes in GO-CP05 peptide sensing system were transformed into valuable information, which achieve the dual-mode quantitative detection of TDEs and its marker CD63, and the actual serum analysis. This matter-energy interaction network was also informationized, and utilized for parallel and batch logic computing, two kinds of molecular crypto-steganography (based on peptide sequence and Boolean logic relationships), which facilitates development of intelligent sensing and advanced information technology. This work not only provides a new method for sensitive detection of important disease markers, but also provides ideas for integrating molecular sensing and informatization to open molecular digitization.

Characterizing Nanoparticle Isolated by Yam Bean (Pachyrhizus erosus) as a Potential Agent for Nanocosmetics: An in vitro and in vivo Approaches

BACKGROUND

This study investigated the potential of Plant-Derived Exosome-Like Nanoparticles (PDENs) as cosmeceutical nanocarriers for treating skin problems, such as scar removal, face rejuvenation, anti-aging, and anti-pigmentation.

OBJECTIVE

Researchers isolated PDENs from Yam Bean (Pachyrhizus erosus) using PEG-based precipitation, gradual filtration, and various centrifugations at low temperatures. Followed by in vitro and in vivo studies using HDF cells and Zebrafish.

METHODS

The morphology of the YB-PDENs was determined using TEM analysis, they had a spherical shape with diameters of 236,83 ± 9,27nm according to PSA. The study found that YB-PDENs were stable in aquabidest at 4°C for one month of storage and had ~-26,5 mV of Zeta Potential. The concentration of YB-PDENs was measured using the BCA Assay, and internalization of YB-PDENs to HDF cells was observed using a Confocal Laser Scanning Microscope labelled with PKH67.

RESULT

As for cytotoxicity, after 24 and 72 hours of incubation with YB-PDENs, the viability of HDF cells remained more than 80%. The study also examined cell migration using the Scratch Assay and found that at 2,5 μg/mL, YB-PDENs had better migration results than other concentrations. Immunocytochemistry showed that collagen expression was higher after 14 days of incubation with YB-PDENs, and melanocytes in zebrafish decreased at each concentration compared with controls.

CONCLUSION

In conclusion, this study is the first to extract and describe PDENs from Yam Bean (Pachyrhizus erosus), with YB-PDENs having a promising anti-melanogenic effect in skin treatment. This study highlights the potential of YB-PDENs as a promising alternative to depigmentation and skin whitening treatments.

MSC-derived exosomes protect auditory hair cells from neomycin-induced damage via autophagy regulation

BACKGROUND

Sensorineural hearing loss (SNHL) poses a major threat to both physical and mental health; however, there is still a lack of effective drugs to treat the disease. Recently, novel biological therapies, such as mesenchymal stem cells (MSCs) and their products, namely, exosomes, are showing promising therapeutic potential due to their low immunogenicity, few ethical concerns, and easy accessibility. Nevertheless, the precise mechanisms underlying the therapeutic effects of MSC-derived exosomes remain unclear.

RESULTS

Exosomes derived from MSCs reduced hearing and hair cell loss caused by neomycin-induced damage in models in vivo and in vitro. In addition, MSC-derived exosomes modulated autophagy in hair cells to exert a protective effect. Mechanistically, exogenously administered exosomes were internalized by hair cells and subsequently upregulated endocytic gene expression and endosome formation, ultimately leading to autophagy activation. This increased autophagic activity promoted cell survival, decreased the mitochondrial oxidative stress level and the apoptosis rate in hair cells, and ameliorated neomycin-induced ototoxicity.

CONCLUSIONS

In summary, our findings reveal the otoprotective capacity of exogenous exosome-mediated autophagy activation in hair cells in an endocytosis-dependent manner, suggesting possibilities for deafness treatment.

Exosomes in skin photoaging: biological functions and therapeutic opportunity

Exosomes are tiny extracellular vesicles secreted by most cell types, which are filled with proteins, lipids, and nucleic acids (non-coding RNAs, mRNA, DNA), can be released by donor cells to subsequently modulate the function of recipient cells. Skin photoaging is the premature aging of the skin structures over time due to repeated exposure to ultraviolet (UV) which is evidenced by dyspigmentation, telangiectasias, roughness, rhytides, elastosis, and precancerous changes. Exosomes are associated with aging-related processes including, oxidative stress, inflammation, and senescence. Anti-aging features of exosomes have been implicated in various in vitro and pre-clinical studies. Stem cell-derived exosomes can restore skin physiological function and regenerate or rejuvenate damaged skin tissue through various mechanisms such as decreased expression of matrix metalloproteinase (MMP), increased collagen and elastin production, and modulation of intracellular signaling pathways as well as, intercellular communication. All these evidences are promising for the therapeutic potential of exosomes in skin photoaging. This review aims to investigate the molecular mechanisms and the effects of exosomes in photoaging.

Mutual regulation of PD-L1 immunosuppression between tumor-associated macrophages and tumor cells: a critical role for exosomes

Tumor cells primarily employ the PD-1/PD-L1 pathway to thwart the anti-tumor capabilities of T lymphocytes, inducing immunosuppression. This occurs through the direct interaction of PD-L1 with PD-1 on T lymphocyte surfaces. Recent research focusing on the tumor microenvironment has illuminated the pivotal role of immune cells, particularly tumor-associated macrophages (TAMs), in facilitating PD-L1-mediated immunosuppression. Exosomes, characterized by their ability to convey information and be engulfed by cells, significantly contribute to promoting TAM involvement in establishing PD-L1-mediated immunosuppression within the tumor microenvironment. Exosomes, characterized by their ability to convey information and be engulfed by cells, significantly contribute to promoting TAM involvement in establishing PD-L1-mediated immunosuppression within the tumor microenvironment. In addition to receiving signals from tumor-derived exosomes that promote PD-L1 expression, TAMs also exert control over PD-L1 expression in tumor cells through the release of exosomes. This paper aims to summarize the mechanisms by which exosomes participate in this process, identify crucial factors that influence these mechanisms, and explore innovative strategies for inhibiting or reversing the tumor-promoting effects of TAMs by targeting exosomes.

Decidual stromal cells-derived exosomes incurred insufficient migration and invasion of trophoblast by disturbing of β-TrCP-mediated snail ubiquitination and degradation in unexplained recurrent spontaneous abortion

BACKGROUND

Exosomes released from decidual stromal cells (DSC-exos) play a crucial role in facilitating the epithelial-mesenchymal transition (EMT) of trophoblasts and insufficient trophoblasts EMT are associated with URSA (unexplained recurrent spontaneous abortion). However, the mechanisms underlying DSC-exos inducing EMT is not completely understood.

METHODS

DSC-exos of normal pregnant women (N-DSC-exos) and URSA patients (URSA-DSC-exos) were extracted and characterized. Characterization of the isolated DSC-exos was performed using with TEM (transmission electron microscopy), NTA (nanoparticle tracking analysis), and WB (western blot) techniques. Subsequently, these DSC-exos were co-cultured with trophoblasts cell lines (HTR-8/SVneo). The influence of both N-DSC-exos and URSA-DSC-exos on trophoblasts proliferation, invasion and migration, as well as on the expression of EMT-related proteins, was evaluated through a series of assays including CCK8 assays, wound healing assays, transwell assays, and western blot, respectively. Then rescue experiments were performed by β-TrCP knockdown or β-TrCP overexpressing trophoblasts with snail-siRNA transfection or β-TrCP overexpressing Lentivirus infection, respectively. Finally, animal experiments were employed to explore the effect of N-DSC-exos on embryo absorption in mice.

RESULTS

We found increased β-TrCP expression in the villus of URSA patients when compared to the normal pregnant women, alongside reduction in the levels of both snail and N-cadherin within URSA patients. N-DSC-exos can promote the EMT of the trophoblast by inhibiting β-TrCP-mediated ubiquitination and degradation of transcription factor snail. Moreover the capacity to promote EMT was found to be more potent in N-DSC-exos than URSA-DSC-exos. Down-regulation of snail or overexpression of β-TrCP can reverse the effects of N-DSC-exos on trophoblast. Finally, in vivo experiment suggested that N-DSC-exos significantly reduced the embryo resorption rate of spontaneous abortion mouse model.

CONCLUSIONS

Our findings indicate that URSA-DSC-exos caused insufficient migration and invasion of trophoblast because of disturbing of β-TrCP-mediated ubiquitination and degradation of EMT transcription factor snail. Elucidating the underlying mechanism of this dysregulation may shed light on the novel pathways through which DSC-exos influence trophoblast function, thereby contributing to our understanding of their role in URSA.

Circ_0006640 transferred by bone marrow-mesenchymal stem cell-exosomes suppresses lipopolysaccharide-induced apoptotic, inflammatory and oxidative injury in spinal cord injury

BACKGROUND

Emerging proofs have shown that differentially expressed circular RNAs (circRNAs) are closely associated with the pathophysiological process of spinal cord injury (SCI). Mesenchymal stem cell (MSC)-exosomes have been demonstrated to possess favorable therapeutic effects in diseases. Herein, this work aimed to investigate the action of circ_0006640 transferred by MSC-exosomes functional recovery after SCI.

METHODS

SCI animal models were established by spinal cord contusion surgery in mice and lipopolysaccharide (LPS)-stimulated mouse microglial cell line BV2. Levels of genes and proteins were detected by qRT-PCR and Western blot. Properties of BV2 cells were characterized using CCK-8 assay, flow cytometry and ELISA analysis. The oxidative stress was evaluated. Dual-luciferase reporter assay was used for verifying the binding between miR-382-5p and circ_0006640 or IGF-1 (Insulin-like Growth Factor 1). Exosome separation was conducted by using the commercial kit.

RESULTS

Circ_0006640 expression was lower in SCI mice and LPS-induced microglial cells. Circ_0006640 overexpression protected microglial cells from LPS-induced apoptotic, inflammatory and oxidative injury. Mechanistically, circ_0006640 directly sponged miR-382-5p, which targeted IGF-1. MiR-382-5p was increased, while IGF-1 was decreased in SCI mice and LPS-induced microglial cells. Knockdown of miR-382-5p suppressed apoptosis, inflammation and oxidative stress in LPS-induced microglial cells, which were reversed by IGF-1 deficiency. Moreover, miR-382-5p up-regulation abolished the protective functions of circ_0006640 in LPS-induced microglial cells. Additionally, circ_0006640 was packaged into MSC-exosomes and could be transferred by exosomes. Exosomal circ_0006640 also had protective effects on microglial cells via miR-382-5p/IGF-1 axis.

CONCLUSION

Circ_0006640 transferred by BMSC-exosomes suppressed LPS-induced apoptotic, inflammatory and oxidative injury via miR-382-5p/IGF-1 axis, indicating a new insight into the clinical application of exosomal circRNA-based therapeutic in the function recovery after SCI.

Exosomes derived from mesenchymal stem cells attenuate NLRP3-related pyroptosis in autoimmune premature ovarian insufficiency via the NF-κB pathway

RESEARCH QUESTION

What is the effect of exosomes derived from bone marrow mesenchymal stem cells (MSC-Exos) on the pyroptosis and recovery of granulosa cells in autoimmune premature ovarian insufficiency (POI)?

DESIGN

In vitro, KGN cells were exposed to interferon-gamma to simulate immune injury. Samples were collected after a 48 h incubation with MSC-Exos (30 μg/ml). The cell viability, secretion of oestrogen and expression of key molecules in pyroptosis and the nuclear factor kappa B (NF-κB) pathway were tested. In vivo, the BALB/c mouse model of autoimmune POI model induced by zona pellucida glycoprotein 3 was used. Fertility testing and sample collection were applied 4 weeks after the ovarian subcapsular injection of MSC-Exos (150 μg for each ovary). Hormone concentration measurements, follicle counting and pyroptotic pathway analyses were conducted for each group.

RESULTS

In vitro, MSC-Exos significantly promoted the proliferation rate and secretion of oestrogen, while at the same time suppressing apoptosis and pyroptosis. In vivo, exosomal treatment normalized the irregular oestrous cycles, rescued the follicular loss and increased the pregnancy rate and number of offspring in POI mice. Elevated serum concentrations of oestrogen and anti-Müllerian hormone, as well as decreased concentrations of FSH and interleukin-1β, were shown. Furthermore, MSC-Exos down-regulated the expression of the NLRP3/Casp1/GSDMD pathway and inhibited activation of the NF-κB pathway.

CONCLUSIONS

These findings demonstrate for the first time that MSC-Exos exert a significant effect on restoring ovarian function in autoimmune POI in vivo and in vitro by suppressing the NLRP3/Casp1/GSDMD pathway and pyroptosis. The NF-κB pathway may contribute to the regulation of NLRP3-related pyroptosis.

miR-21-5p-loaded bone mesenchymal stem cell-derived exosomes repair ovarian function in autoimmune premature ovarian insufficiency by targeting MSX1

RESEARCH QUESTION

What is the effect of micro-RNA (miR)-21-5p-loaded bone marrow mesenchymal stem cell-derived exosomes (miR-21-Exo) on autoimmune premature ovarian insufficiency (POI)?

DESIGN

The Cell Counting Kit 8 (CCK8) assay, fluorescence-activated cell sorting, western blotting, quantitative reverse transcriptase (qRT)-PCR and enzyme-linked immunosorbent assay (ELISA) verified the effect of miR-21-Exo on interferon-γ (IFN-γ)-induced KGN cells. qRT-PCR, western blotting and dual-luciferase reporter gene assays verified that miR-21-Exo mediated Msh homeobox 1 (MSX1) regulation of the Notch signalling pathway and that miR-21 interacted directly with MSX1. The effects of miR-21-Exo on the ovaries were verified by monitoring of the oestrous cycle, haematoxylin and eosin staining, follicle counts, ELISA, immunohistochemistry, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL), western blotting and qRT-PCR.

RESULTS

The results showed that miR-21-Exo promoted IFN-γ-induced KGN cell proliferation and hormone synthesis, and inhibited apoptosis. Using dual-luciferase reporter gene assays, miR-21 and MSX1 were shown to have direct interactions. Moreover, the findings elucidated that miR-21-Exo inhibited cell apoptosis and promoted hormone synthesis by mediating MSX1 to regulate the Notch signalling pathway. miR-21-Exo restored the ovarian structure in a mouse model of autoimmune POI, promoted endocrine function and proliferation, and inhibited apoptosis and inflammation in vivo.

CONCLUSIONS

This study demonstrates that miR-21-Exo regulates the MSX1-mediated Notch signalling pathway to inhibit granulosa cell apoptosis and improve hormone synthesis function, providing insight into a potential mechanism of molecular therapy for the treatment of autoimmune POI.

Exosome Content-Mediated Signaling Pathways in Multiple Sclerosis

Exosomes are small extracellular vesicles with a complex lipid-bilayer surface and 30-150 nm diameter. These vesicles play a critical role in intercellular signaling networks during physiopathological processes through data trafficking and cell reprogramming. It has been demonstrated that exosomes are involved in a variety of central nervous system (CNS) disorders such as multiple sclerosis (MS). Exosome mediators' cell-to-cell communication is possibly by delivering their contents such as proteins, RNAs (coding and non-coding), DNAs (mitochondrial and genomic), and transposable elements to the target cells. Exosomal microRNAs (miRNAs) differ in their expression patterns in MS disease, thereby providing novel diagnostic and prognostic biomarkers and therapeutic options for better treatment of MS disease. Furthermore, these microvesicles are non-immunogenic and non-toxic therapeutic tools for transferring miRNAs across the blood-brain barrier (BBB). Collectively, exosomes could be used as novel drug delivery devices for the treatment of MS patients. This review summarized research regarding the exosomes from serum, plasma, PBMC, and other cells in MS patients and experimental models. We also provide a critical view of exosome content-mediated signaling pathways in MS, including TNF-α, TGF-β, NF-κB, and Wnt pathways. The use of exosomes as a therapeutic potential in MS has also been discussed.

Engineered exosomes mediated targeted delivery of neuroprotective peptide NR2B9c for the treatment of traumatic brain injury

Neuroprotection is one of the core treatment strategies for brain injuries including traumatic brain injury (TBI). NR2B9c is a promising neuroprotective peptide but its clinical translation is limited because of poor brain penetrability. Exosomes are naturally occurring nanovesicles having therapeutic potential for TBI as well as an efficient drug delivery carrier to the brain. Here, we engineered exosomes with neuron targeting peptide rabies virus glycoprotein (RVG29) via bio-orthogonal click chemistry technique and loaded it with NR2B9c, developing RVG-ExoNR2B9c. RVG29 conjugated exosome had higher neuron targeting efficiency compared to naïve exosomes both in vivo and in vitro. RVG-ExoNR2B9c had great cytoprotective effect against oxygen glucose deprived Neuro2a cells. Intravenous administration of RVG-ExoNR2B9c significantly improved behavioral outcomes and reduced the lesion volume after TBI injury in a mice controlled cortical impact model. Due to their multifunctionality and significant efficacy, we anticipate that RVG-ExoNR2B9c have the potential to be translated both as therapeutic agent as well as cargo delivery system to the brain for the treatment of TBI.

Cancer-Associated Fibroblast-Secreted Exosomes Promote Gastric Cancer Cell Migration and Invasion via the IL-32/ESR1 Axis

Exosomes secreted by cancer-associated fibroblasts (CAFs) play a critical part in cancer progression. This study aimed to explore the effects of CAF-exosomes on gastric cancer (GC) cell metastasis. AGS and HGC-27 cells were treated with exosomes and cell viability, migration, and invasion were evaluated using Cell-Counting Kit-8 and Transwell assays. Exosome-regulated mRNAs were explored using quantitative real-time PCR. The relationship between interleukin (IL)32 and estrogen receptor 1 (ESR1) was evaluated using co-immunoprecipitation and dual-luciferase reporter assays. The results of this study show that CAF-derived exosomes promote GC cell viability, migration, and invasion. Exosome treatment increased the levels of IL32, which interacted with ESR1 and negatively regulated ESR1 levels. Rescue experiments were conducted to demonstrate that CAF-exosomes promoted biological behaviors of GC cells by upregulating IL32 and downregulating ESR1 expression. In conclusion, CAF-derived exosomes promote GC cell viability, migration, and invasion by elevating the IL32/ESR1 axis, suggesting a novel strategy for metastatic GC treatment.

Menstrual blood-derived stem cells exosomal miR-let-7 to ameliorate pulmonary fibrosis through inhibiting ferroptosis by Sp3/HDAC2/Nrf2 signaling pathway

Idiopathic pulmonary fibrosis (IPF) is a serious, lifelong lung disease with high morbidity and high mortality. Menstrual blood-derived stem cells (MenSCs) derived exosomes (MenSCs-Exo) emerge as an attractive tool for the treatment of acute lung injury and fibrosis-related diseases. However, more comprehensive mechanism over how MenSCs derived exosomes exhibits anti-pulmonary fibrosis needs to be elucidated. In this study, TGF-β was used to construct cell fibrosis model, and bleomycin (BLM) was applied to induce lung tissue fibrosis mice model. BLM- and TGF-β1-induced cellular reactive oxygen species (ROS), mitochondrial DNA (mtDNA) damage, and lung epithelial cell apoptosis were alleviated by MenSCs-Exo treatment in vivo and in vitro. Besides, it was found that MenSCs-Exo delivered miR-let-7 into MLE-12 cells/lung epithelial cell and the reduction of miR-let-7 blocked the improvement produced by MenSCs-Exo. Mechanistically, miR-let-7 directly bound to Sp3 and negatively regulated its expression. Sp3 elevation promoted the expression of ferroptosis-related protein and mitochondrial DNA (mtDNA) damage markers via recruiting HDAC2, thereby inactivating keap1/Nrf2 signal cascade, which were confirmed in BLM-induced pulmonary fibrosis mice model under the combination therapy of the MenSCs-Exo and let-7 inhibitor. Collectively, MenSCs derived exosomes could transmit miR-let-7 into MLE-12 cells to inhibit the expression of Sp3, thereby weakening the recruitment effect of Sp3 on HDAC2, lifting the deacetylation restriction of HDAC2 on Nrf2, and enhancing the Nrf2 pathway. These changes further declined ferroptosis and delayed the pathological process of oxidative damage and lung epithelial cell apoptosis in PF.

Hypoxia-induced ZEB1 promotes cervical cancer immune evasion by strengthening the CD47-SIRPα axis

BACKGROUND

The dynamic interaction between cancer cells and tumour-associated macrophages (TAMs) in the hypoxic tumour microenvironment (TME) is an active barrier to the effector arm of the antitumour immune response. Cancer-secreted exosomes are emerging mediators of this cancer-stromal cross-talk in the TME; however, the mechanisms underlying this interaction remain unclear.

METHODS

Exosomes were isolated with ExoQuick exosome precipitation solution. The polarizing effect of TAMs was evaluated by flow cytometry, western blot analysis, immunofluorescence staining and in vitro phagocytosis assays. Clinical cervical cancer specimens and an in vivo xenograft model were also employed.

RESULTS

Our previous study showed that hypoxia increased the expression of ZEB1 in cervical squamous cell carcinoma (CSCC) cells, which resulted in increased infiltration of TAMs. Here, we found that hypoxia-induced ZEB1 expression is closely correlated with CD47-SIRPα axis activity in CSCC, which enables cancer cells to evade phagocytosis by macrophages and promotes tumour progression. ZEB1 was found to directly activate the transcription of the CD47 gene in hypoxic CSCC cells. We further showed that endogenous ZEB1 was characteristically enriched in hypoxic CSCC cell-derived exosomes and transferred into macrophages via these exosomes to promote SIRPα+ TAM polarization. Intriguingly, exosomal ZEB1 retained transcriptional activity and reprogrammed SIRPα+ TAMs via activation of the STAT3 signalling pathway in vitro and in vivo. STAT3 inhibition reduced the polarizing effect induced by exosomal ZEB1. Knockdown of ZEB1 increased the phagocytosis of CSCC cells by macrophages via decreasing CD47 and SIRPα expression.

CONCLUSIONS

Our results suggest that hypoxia-induced ZEB1 promotes immune evasion in CSCC by strengthening the CD47-SIRPα axis. ZEB1-targeted therapy in combination with CD47-SIRPα checkpoint immunotherapy may improve the outcomes of CSCC patients in part by disinhibiting innate immunity.

Synergistic vesicle-vector systems for targeted delivery

With the immense progress in drug delivery systems (DDS) and the rise of nanotechnology, challenges such as target specificity remain. The vesicle-vector system (VVS) is a delivery system that uses lipid-based vesicles as vectors for a targeted drug delivery. When modified with target-probing materials, these vesicles become powerful vectors for drug delivery with high target specificity. In this review, we discuss three general types of VVS based on different modification strategies: (1) vesicle-probes; (2) vesicle-vesicles; and (3) genetically engineered vesicles. The synthesis of each VVS type and their corresponding properties that are advantageous for targeted drug delivery, are also highlighted. The applications, challenges, and limitations of VVS are briefly examined. Finally, we share a number of insights and perspectives regarding the future of VVS as a targeted drug delivery system at the nanoscale.

Metabolomic profiling of exosomes reveals age-related changes in ovarian follicular fluid

BACKGROUND

Female fertility declines with increased maternal age, and this decline is even more rapid after the age of 35 years. Follicular fluid (FF) is a crucial microenvironment that plays a significant role in the development of oocytes, permits intercellular communication, and provides the oocytes with nutrition. Exosomes have emerged as being important cell communication mediators that are linked to age-related physiological and pathological conditions. However, the metabolomic profiling of FF derived exosomes from advanced age females are still lacking.

METHODS

The individuals who were involved in this study were separated into two different groups: young age with a normal ovarian reserve and advanced age. The samples were analysed by using gas chromatography-time of flight mass spectrometry (GC-TOFMS) analysis. The altered metabolites were analysed by using Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis to identify the functions and pathways that were involved.

RESULTS

Our data showed that metabolites in exosomes from FF were different between women of young age and women of advanced age. The set of 17 FF exosomal metabolites (P ≤ 0.05) may be biomarkers to differentiate between the two groups. Most of these differentially expressed metabolites in FF were closely involved in the regulation of oocyte number and hormone levels.

CONCLUSIONS

In this study, we identified differences in the metabolites of exosomes from FF between women of young age and women of advanced age. These different metabolites were tightly related to oocyte count and hormone levels. Importantly, these findings elucidate the metabolites of the FF exosomes and provide a better understanding of the nutritional profiles of the follicles with age.

Exosome-mediated delivery of super-repressor IκBα alleviates inflammation and joint damages in rheumatoid arthritis

BACKGROUND

This study aims to investigate the potential anti-inflammatory effects of exosomes engineered to carry super-repressor IκB (Exo-srIκB), an exosome-based NF-κB inhibitor, in the context of RA.

METHODS

Peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) were collected from patients diagnosed with RA and treated with Exo-srIκB to test the therapeutic potential. Flow cytometry analysis was performed to assess the production of inflammatory cytokines (IL-17A and GM-CSF) by the cells. ELISA was utilized to measure the levels of TNF-α, IL-17A, IL-6, and GM-CSF. Arthritis was induced in SKG mice by intraperitoneal injection of curdlan. DBA/1 J mice were used in collagen-induced arthritis (CIA) experiments. After the development of arthritis, mice were injected with either Exo-Naïve (control exosome) or Exo-srIκB. Arthritis scores were recorded biweekly, and histological observations of the ankle joint were conducted using H&E and safranin-O staining. Additionally, bone erosion was evaluated using micro-CT imaging.

RESULTS

In the ex vivo study involving human PBMCs and SFMCs, treatment with Exo-srIκB demonstrated a notable reduction in inflammatory cytokines. Furthermore, in both the SKG and CIA models, Exo-srIκB treatment exhibited significant reductions in inflammation, cartilage destruction, and bone erosion within the joint tissues when compared to the Exo-Naive control group. Additionally, the radiographic score assessed through microCT showed a significant decrease compared to the Exo-Naive control group.

CONCLUSION

Overall, these findings suggest that Exo-srIκB possesses anti-inflammatory properties in human RA cells and animal models, making it a promising therapeutic candidate for the treatment of RA.

Recent Progress in Prompt Molecular Detection of Exosomes Using CRISPR/Cas and Microfluidic-Assisted Approaches Toward Smart Cancer Diagnosis and Analysis

Exosomes are essential indicators of molecular mechanisms involved in interacting with cancer cells and the tumor environment. As nanostructures based on lipids and nucleic acids, exosomes provide a communication pathway for information transfer by transporting biomolecules from the target cell to other cells. Importantly, these extracellular vesicles are released into the bloodstream by the most invasive cells, i. e., cancer cells; in this way, they could be considered a promising specific biomarker for cancer diagnosis. In this matter, CRISPR-Cas systems and microfluidic approaches could be considered practical tools for cancer diagnosis and understanding cancer biology. CRISPR-Cas systems, as a genome editing approach, provide a way to inactivate or even remove a target gene from the cell without affecting intracellular mechanisms. These practical systems provide vital information about the factors involved in cancer development that could lead to more effective cancer treatment. Meanwhile, microfluidic approaches can also significantly benefit cancer research due to their proper sensitivity, high throughput, low material consumption, low cost, and advanced spatial and temporal control. Thereby, employing CRISPR-Cas- and microfluidics-based approaches toward exosome monitoring could be considered a valuable source of information for cancer therapy and diagnosis. This review assesses the recent progress in these promising diagnosis approaches toward accurate cancer therapy and in-depth study of cancer cell behavior.

Exosome-mediated repair of spinal cord injury: a promising therapeutic strategy

Spinal cord injury (SCI) is a catastrophic injury to the central nervous system (CNS) that can lead to sensory and motor dysfunction, which seriously affects patients' quality of life and imposes a major economic burden on society. The pathological process of SCI is divided into primary and secondary injury, and secondary injury is a cascade of amplified responses triggered by the primary injury. Due to the complexity of the pathological mechanisms of SCI, there is no clear and effective treatment strategy in clinical practice. Exosomes, which are extracellular vesicles of endoplasmic origin with a diameter of 30-150 nm, play a critical role in intercellular communication and have become an ideal vehicle for drug delivery. A growing body of evidence suggests that exosomes have great potential for repairing SCI. In this review, we introduce exosome preparation, functions, and administration routes. In addition, we summarize the effect and mechanism by which various exosomes repair SCI and review the efficacy of exosomes in combination with other strategies to repair SCI. Finally, the challenges and prospects of the use of exosomes to repair SCI are described.

M2 macrophage-derived exosomes induce angiogenesis and increase skin flap survival through HIF1AN/HIF-1α/VEGFA control

BACKGROUND

Skin flap transplantation is a routine strategy in plastic and reconstructive surgery for skin-soft tissue defects. Recent research has shown that M2 macrophages have the potential for pro-angiogenesis during tissue healing.

METHODS

In our research, we extracted the exosomes from M2 macrophages(M2-exo) and applied the exosomes in the model of skin flap transplantation. The flap survival area was measured, and the choke vessels were assessed by morphological observation. Hematoxylin and eosin (H&E) staining and Immunohistochemistry were applied to assess the neovascularization. The effect of M2-exo on the function of Human umbilical vein endothelial cells (HUVECs) was also investigated. We also administrated 2-methoxyestradiol (2-ME2, an inhibitor of HIF-1α) to explore the underlying mechanism. We tested the effects of M2-Exo on the proliferation of HUVECs through CCK8 assay and EdU staining assay.

RESULTS

The survival area and number of micro-vessels in the skin flaps were increased in the M2-exo group. Besides, the dilation rate of choke vessels was also enhanced in the M2-exo group. Additionally, compared with the control group, M2-exo could accelerate the proliferation, migration and tube formation of HUVECs in vitro. Furthermore, the expression of the pro-angiogenesis factors, HIF-1α and VEGFA, were overexpressed with the treatment of the M2-exo. The expression of HIF1AN protein level was decreased in the M2-exo group. Finally, treatment with HIF-1α inhibitor reverses the pro-survival effect of M2-exo on skin flaps by interfering with the HIF1AN/HIF-1α/VEGFA signaling pathway.

CONCLUSION

This study showed that M2-exosomes promote skin flap survival by enhancing angiogenesis, with HIF1AN/HIF-1α/VEGFA playing a crucial role in this process.

Effect of miR-412-5p-loaded exosomes in H9c2 cardiomyocytes via the MAPK pathway

Objectives

MicroRNAs (miRNAs) are small non-coding RNAs that function in all biological processes. Recent findings suggest that exosomes, which are small vesicles abundantly secreted by various cell types, can transport miRNAs to target cells. Here, we elucidated the effect of miRNA-loaded exosomes on lipopolysaccharide (LPS)-induced inflammation in H9c2 cardiomyocytes.

Materials and Methods

Exosomes were isolated from mesenchymal stem cells (MSC) and loaded with miR-412-5p. Additionally, the effect of the miR-412-5p-loaded exosomes on LPS-induced inflammation in H9c2 cardiomyocytes was evaluated by assessing the levels of nitric oxide (NO), reactive oxygen species (ROS), and prostaglandin E2 (PGE2). The expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), inflammatory cytokines, and mitogen-activated protein kinase (MAPK) signaling factors was evaluated using reverse transcription-quantitative PCR and western blotting.

Results

miR-412-5p-loaded exosomes inhibited LPS-induced secretion of inflammatory mediators (NO, PGE2, and ROS), pro-inflammatory cytokines (IL-1β and IL-6), and COX-2 and iNOS expression. Additionally, miR-412-5p-loaded exosomes significantly decreased the expression of MAPK signaling molecules, including p-extracellular signal-regulated kinase (ERK), p-p38, and p-Jun kinase (JNK), in H9c2 cardiomyocytes.

Conclusion

These findings showed that miR-412-5p-loaded exosomes ameliorated LPS-induced inflammation in H9c2 cardiomyocytes by inhibiting COX-2 and iNOS expression, inflammatory mediators, and pro-inflammatory cytokines via the MAPK pathway. The findings indicate that miR-412-5p-loaded exosomes may be effective for the prevention of myocardial injury.

Tumor-derived Exosomal ENO2 Modulates Polarization of Tumor-associated Macrophages through Reprogramming Glycolysis to Promote Progression of Diffuse Large B-cell Lymphoma

Macrophages can be polarized into functional classically activated (M1) or alternatively activated (M2) phenotype. Tumor-associated macrophages (TAMs) mainly exhibit M2 phenotype. Previous works determined that up-regulation of enolase 2 (ENO2) in diffuse large B-cell lymphoma (DLBCL) cells can promote macrophages to an M2-like phenotype, thereby consequently promoting the progression of DLBCL. Exosomes are a subset of extracellular vesicles, carrying various bioactive molecules, mediate signals transduction and regulate immune cells. In our study, we investigated the role and related mechanisms of DLBCL-derived exosomal ENO2 in regulating macrophage polarization during DLBCL progression via bioinformatics analysis and a series of experiments. The results of bioinformatics analysis indicated that high expression of ENO2 was positively correlated with DLBCL progression and macrophages M2/M1 ratio. ENO2 protein levels were increased in the exosomes of the sera of DLBCL patients and DLBCL cells. Moreover, the DLBCL-derived exosomes were assimilated by macrophages and then regulated macrophage polarization. The results of in vitro and in vivo experiments showed that DLBCL-derived exosomal ENO2 modulated macrophages polarization (increased M2 phenotype and decreased M1 phenotype), thereby promoting DLBCL proliferation, migration, and invasion. We then revealed that the modulation of macrophages polarization by DLBCL-derived exosomal ENO2 depended on glycolysis and was promoted through GSK3β/β-catenin/c-Myc signaling pathway. These findings suggested that DLBCL-derived exosomal ENO2 accelerated glycolysis via GSK3β/β-catenin/c-Myc signaling pathway to ultimately promote macrophages to an M2-like phenotype, which can promote the proliferation, migration and invasion of DLBCL, suggesting that exosomal ENO2 may be a promising therapeutic target and prognostic biomarker for DLBCL.

Extracellular vesicles in degenerative retinal diseases: A new therapeutic paradigm

Nanoscale extracellular vesicles (EVs), consisting of exomers, exosomes and microvesicles/ectosomes, have been extensively investigated in the last 20 years, although their biological role is still something of a mystery. EVs are involved in the transfer of lipids, nucleic acids and proteins from donor to recipient cells or distant organs as well as regulating cell-cell communication and signaling. Thus, EVs are important in intercellular communication and this is not limited to sister cells, but may also mediate the crosstalk between different cell types even over long distances. EVs play crucial functions in both cellular homeostasis and the pathogenesis of diseases, and since their contents reflect the status of the donor cell, they represent an additional valuable source of information for characterizing complex biological processes. Recent advances in isolation and analytical methods have led to substantial improvements in both characterizing and engineering EVs, leading to their use either as novel biomarkers for disease diagnosis/prognosis or even as novel therapies. Due to their capacity to carry biomolecules, various EV-based therapeutic applications have been devised for several pathological conditions, including eye diseases. In the eye, EVs have been detected in the retina, aqueous humor, vitreous body and also in tears. Experiences with other forms of intraocular drug applications have opened new ways to use EVs in the treatment of retinal diseases. We here provide a comprehensive summary of the main in vitro, in vivo, and ex vivo literature-based studies on EVs' role in ocular physiological and pathological conditions. We have focused on age-related macular degeneration, diabetic retinopathy, glaucoma, which are common eye diseases leading to permanent blindness, if not treated properly. In addition, the putative use of EVs in retinitis pigmentosa and other retinopathies is discussed. Finally, we have reviewed the potential of EVs as therapeutic tools and/or biomarkers in the above-mentioned retinal disorders. Evidence emerging from experimental disease models and human material strongly suggests future diagnostic and/or therapeutic exploitation of these biological agents in various ocular disorders with a good possibility to improve the patient's quality of life.

lncRNA BANCR promotes the colorectal cancer metastasis through accelerating exosomes-mediated M2 macrophage polarization via regulating RhoA/ROCK signaling

Cancer cells-derived exosomal lncRNAs could modulate the tumorigenesis of colorectal cancer (CRC) via modulating macrophage M2 polarization. However, the clarified mechanism and function of lncRNA BANCR in CRC remains unclear. Exosomes were identified by TEM, NTA, western blot and fluorescent staining. M2 macrophages were identified by CD206 and CD163 expressions using by flow cytometry and RT-qPCR. In addition, the relation between IGF2BP2 and BANCR or RhoA were explored by RIP assay. The malignant behaviors of CRC cells were examined by CCK-8, EdU and transwell assays. Histopathological changes in mice were observed by H&E staining. Silencing of BANCR notably inhibited the proliferation, migration and invasion of CRC cells. SW620 and HCT-15 cells-derived exosomal BANCR positively regulated the macrophage M2 polarization. In addition, exosomal BANCR remarkably enhanced the promoting roles mediated by M2 macrophages on proliferation and invasion in CRC cells. Meanwhile, exosomal BANCR promoted the M2 macrophage polarization via activation of RhoA/Rock pathway by recruiting IGF2BP2. Inhibition of RhoA/Rock pathway reversed exosomal BANCR-mediated macrophages M2 polarization and CRC malignant behaviors in SW620 and HCT-15 cells. Exosomal lncRNA BANCR derived from SW620 and HCT-15 cells promoted the metastasis of CRC via inducing the polarization of M2 macrophages. Thus, BANCR might be a new target for the treatment of CRC.

Ambra1 in exosomes secreted by HK-2 cells damaged by supersaturated oxalate induce mitophagy and autophagy-ferroptosis in normal HK-2 cells to participate in the occurrence of kidney stones

Injury to the renal tubular epithelium has emerged as a leading factor underlying the formation of kidney stones. Indeed, epithelial cell damage contributes to the adherence and aggregation of crystals, thereby accelerating the formation of renal stones. Meanwhile, exosomes play an instrumental role in cellular communication, including DNA, RNA, mRNA, etc. In this study, homogenous cells were treated with exosomes derived from damaged cells in an attempt to establish "positive feedback" of cell damage, and the desired results were achieved. To begin, a serum-free medium and supersaturated concentrations of oxalate were added to the HK-2 cell line, and then exosomes were isolated from the two groups for analysis and comparison, and the autophagy-related gene Ambra1 (autophagy and beclin-1 regulator 1) was detected. Subsequently, normal HK-2 cells were treated with exosomes, and the related indexes of autophagy, ferroptosis and mitophagy were determined. Thereafter, Ambra1 was knocked down in exosome-derived HK-2 cells, resulting in the down-regulation of Ambra1 expression in exosomes produced by HK-2 cells following oxalate intervention. Thereafter, the ability of exosomes to stimulate autophagy, mitophagy and ferroptosis was re-evaluated in HK-2 cells after Ambra1 knockdown. The results corroborated that exosomes secreted by oxalate-treated HK-2 can directly elevate autophagy, ferroptosis and mitophagy levels in normal cells, and this effect was significantly mitigated following Ambra1 knockdown within exosomes. Meanwhile, exosomes-induced autophagy and ferroptosis were alleviated after knockdown of beclin-1 in recipient HK-2 cells. These results further suggest that beclin-1 plays a critical role in the process of exosome-induced autophagy-ferroptosis.

Applications of Exosome Vesicles in Different Cancer Types as Biomarkers

One of the biggest challenges in the fight against cancer is early detection. Early diagnosis is vital, but there are some barriers such as economic, cultural, and personal factors. Considering the disadvantages of radiological imaging techniques or serological analysis methods used in cancer diagnosis, such as being expensive, requiring expertise, and being time-consuming, there is a need to develop faster, more reliable, and cost-effective diagnostic methods for use in cancer diagnosis. Exosomes, which are responsible for intercellular communication with sizes ranging from 30-120 nm, are naturally produced biological nanoparticles. Thanks to the cargo contents they carry, they are a potential biomarker to be used in the diagnosis of cancer. Exosomes, defined as extracellular vesicles of endosomal origin, are effective in cancer growth, progression, metastasis, and drug resistance, and changes in microenvironmental conditions during tumor development change exosome secretion. Due to their high cellular activity, tumor cells produce much higher exosomes than healthy cells. Therefore, it is known that the number of exosomes in body fluids is significantly rich compared to other cells and can act as a stand-alone diagnostic biomarker. Cancer- derived exosomes have received great attention in recent years for the early detection of cancer and the evaluation of therapeutic response. In this article, the content, properties, and differences of exosomes detected in common types of cancer (lung, liver, pancreas, ovaries, breast, colorectal), which are the leading causes of cancer-related deaths, are reviewed. We also discuss the potential utility of exosome contents as a biomarker for early detection, which is known to be important in targeted cancer therapy.

Exosomes derived from CD271+CD56+ bone marrow mesenchymal stem cell subpopoulation identified by single-cell RNA sequencing promote axon regeneration after spinal cord injury

Rationale: Spinal cord injury (SCI) results in neural tissue damage. However, the limited regenerative capacity of adult mammals' axons upon SCI leads to persistent neurological dysfunction. Thus, exploring the pathways that can enhance axon regeneration in injured spinal cord is of great significance. Methods: Through the utilization of single-cell RNA sequencing in this research, a distinct subpopulation of bone marrow mesenchymal stem cells (BMSCs) that exhibits the capacity to facilitate axon regeneration has been discovered. Subsequently, the CD271+CD56+ BMSCs subpopulation was isolated using flow cytometry, and the exosomes derived from this subpopulation (CD271+CD56+ BMSC-Exos) were extracted and incorporated into a hydrogel to create a sustained release system. The aim was to investigate the therapeutic effects of CD271+CD56+ BMSC-Exos and elucidate the underlying mechanisms involved in promoting axon regeneration and neural function recovery. Results: The findings indicate that CD271+CD56+ BMSC-Exos share similar physical and chemical properties with conventional exosomes. Importantly, in an SCI model, in situ implantation of CD271+CD56+ BMSC-Exos hydrogel resulted in increased expression of NF and synaptophysin, markers associated with axon regeneration and synapse formation, respectively. This intervention also contributed to improved neural function recovery. In vitro experiments demonstrated that CD271+CD56+ BMSC-Exos treatment significantly enhanced axon extension distance and increased the number of branches in dorsal root ganglion axons. Moreover, further investigation into the molecular mechanisms underlying CD271+CD56+ BMSC-Exos-mediated axon regeneration revealed the crucial involvement of the miR-431-3p/RGMA axis. Conclusion: In summary, the implantation of CD271+CD56+ BMSC-Exos hydrogel presents a promising and effective therapeutic approach for SCI.

Mass Spectrometry-Based Characterization of Protein Aggregates in Tissues and Biofluids

Protein aggregation is a common mechanism in multiple neurodegenerative and heart diseases and the accumulation of proteins in aggregates is toxic to cells, causing injury and death. The degree of protein aggregation directly correlates with the severity of the disease. Misfolded proteins present thermodynamic barriers that culminate in the loss of structure and function and the exposure of hydrophobic residues. The exposure of hydrophobic residues is the driving force behind protein aggregation, as it reduces surface free energy and increases the propensity for the formation of large insoluble aggregates. Exploring the protein content of aggregates is fundamental to understanding their formation mechanism and pathophysiological effects. We demonstrate here a method for isolating aggregated protein content in human plasma and mouse brain samples. The samples were characterized by mass spectrometry analysis, transmission electron microscopy, and western blotting. We report the identification of proteins associated with neurodegenerative diseases in the isolated pellets. The western blotting analyses of the isolated pellet showed the positivity for CD89 and CD63, consolidated markers of exosomes, confirming the presence of exosomes within the pellet but not in the supernatant in human plasma. Notably, the concomitant isolation of exosomes together with the protein aggregates was feasible starting from 200 μL of human plasma. Moreover, the presented methodology separated albumin from the aggregated pellet, allowing identification of larger diversity of proteins through mass spectrometry analysis.

Exosomal microRNA profiling revealed enhanced autophagy suppression and anti-tumor effects of a combination of compound Phyllanthus urinaria and lenvatinib in hepatocellular carcinoma

BACKGROUND

Compound Phyllanthus urinaria (CP), a traditional Chinese herbal remedy, possesses strong anti-cancer effects and is extensively employed in the clinical management of hepatocellular carcinoma (HCC). While lenvatinib and other oral tyrosine kinase inhibitors have been authorized as initial treatments for advanced unresectable HCC, the survival of patients is ultimately restricted due to the gradual development of drug resistance. Fortunately, the co-administration of CP and lenvatinib holds promise for anti-cancer applications.

PURPOSE

Our objective was to understand the molecular-level mechanisms of bioactive phytocompounds in CP, in order to explore the anti-HCC effects of combining CP and lenvatinib treatment and reveal the underlying mechanisms. Furthermore, we discovered new miRNAs associated with autophagy that are common to both HepG2-derived exosomes and HepG2 cells. These miRNAs play a role in the advancement of HCC and were identified through the utilization of CP and lenvatinib.

METHODS

To assess the anti-HCC effects of CP in combination with lenvatinib, both an in vitro CCK-8 assay and an in vivo xenograft model assay were performed. TEM, NTA, and nano-flow cytometry were employed for the identification of isolated exosomes. To ascertain the miRNA expression patterns in HepG2 cells and HepG2-derived exosomes, miRNA-sequencing analysis was conducted. Further investigation involved the use of real-time PCR, examination of the fusion protein GFP-mRFP-LC3, TEM analysis, and western blotting.

RESULTS

In vitro and in vivo, the combination of CP and lenvatinib showed a stronger and more powerful impact on HCC compared to either CP or lenvatinib alone. The combination of CP and lenvatinib had a significant impact on autophagy-related miRNAs in HepG2-derived exosomes and HepG2 cells, as demonstrated by cellular and exosomal miRNA sequencing. Additional tests indicated that the increased inhibition of autophagy in HepG2 cells subjected to CP treatment, as well as the combination of CP and lenvatinib, was accomplished through the regulation of Beclin-1, LC3-II, and P62 expression.

CONCLUSION

In conclusion, our results indicate that the combination of CP and lenvatinib can effectively inhibit HCC by promoting the exosome-mediated suppression of autophagy. This novel therapeutic option is highly efficient and durable, making it a promising treatment for HCC. Moreover, the miRNAs that are differentially expressed and associated with exosome-mediated autophagy, which have been discovered in this study, could potentially be targeted for clinical treatment of HCC.

Hypoxia Induces Tumor-Derived Exosome SNHG16 to Mediate Nasopharyngeal Carcinoma Progression through the miR-23b-5p/MCM6 Pathway

This study aims to investigate the mechanism of tumor-derived exosomal (EVs) SNHG16 in promoting the progression of nasopharyngeal carcinoma (NPC). QRT-PCR was used to detect the expression of SNHG16, miR-23b-5p and MCM6 in NPC. MTT, flow cytometry and transwell were used to detect the effects of them on the proliferation, cycle, apoptosis and invasion ability of NPC. Transmission electron microscopy, Western blotting and BCA were used to verify the regulation of exosome secretion under different oxygen environments. Our results showed that hypoxia induces tumor-derived exosome SNHG16 to mediate NPC progression through the miR-23b-5p/MCM6 pathway.

Small RNA-big impact: exosomal miRNAs in mitochondrial dysfunction in various diseases

Mitochondria are multitasking organelles involved in maintaining the cell homoeostasis. Beyond its well-established role in cellular bioenergetics, mitochondria also function as signal organelles to propagate various cellular outcomes. However, mitochondria have a self-destructive arsenal of factors driving the development of diseases caused by mitochondrial dysfunction. Extracellular vesicles (EVs), a heterogeneous group of membranous nano-sized vesicles, are present in a variety of bodily fluids. EVs serve as mediators for intercellular interaction. Exosomes are a class of small EVs (30-100 nm) released by most cells. Exosomes carry various cargo including microRNAs (miRNAs), a class of short noncoding RNAs. Recent studies have closely associated exosomal miRNAs with various human diseases, including diseases caused by mitochondrial dysfunction, which are a group of complex multifactorial diseases and have not been comprehensively described. In this review, we first briefly introduce the characteristics of EVs. Then, we focus on possible mechanisms regarding exosome-mitochondria interaction through integrating signalling networks. Moreover, we summarize recent advances in the knowledge of the role of exosomal miRNAs in various diseases, describing how mitochondria are changed in disease status. Finally, we propose future research directions to provide a novel therapeutic strategy that could slow the disease progress mediated by mitochondrial dysfunction.

Improving cancer immunotherapy by preventing cancer stem cell and immune cell linking in the tumor microenvironment

Cancer stem cells are the key link between malignant tumor progression and drug resistance. This cell population has special properties that are different from those of conventional tumor cells, and the role of cancer stem cell-related exosomes in progression of tumor malignancy is becoming increasingly clear. Cancer stem cell-derived exosomes carry a variety of functional molecules involved in regulation of the microenvironment, especially with regard to immune cells, but how these exosomes exert their functions and the specific mechanisms need to be further clarified. Here, we summarize the role of cancer stem cell exosomes in regulating immune cells in detail, aiming to provide new insights for subsequent targeted drug development and clinical strategy formulation.