Exosomes In Progression Research Articles

Small but Mighty—Exosomes, Novel Intercellular Messengers in Neurodegeneration

Simple SummaryExosomes are biological nanoparticles recently recognized as intercellular messengers. They contain a cargo of lipids, proteins, and RNA. They can transfer their content to not only cells in the vicinity but also to cells at a distance. This unique ability empowers them to modulate the physiology of recipient cells. In brain, exosomes play a role in neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease and amyotrophic lateral sclerosis.Exosomes of endosomal origin are one class of extracellular vesicles that are important in intercellular communication. Exosomes are released by all cells in our body and their cargo consisting of lipids, proteins and nucleic acids has a footprint reflective of their parental origin. The exosomal cargo has the power to modulate the physiology of recipient cells in the vicinity of the releasing cells or cells at a distance. Harnessing the potential of exosomes relies upon the purity of exosome preparation. Hence, many methods for isolation have been developed and we provide a succinct summary of several methods. In spite of the seclusion imposed by the blood–brain barrier, cells in the CNS are not immune from exosomal intrusive influences. Both neurons and glia release exosomes, often in an activity-dependent manner. A brief description of exosomes released by different cells in the brain and their role in maintaining CNS homeostasis is provided. The hallmark of several neurodegenerative diseases is the accumulation of protein aggregates. Recent studies implicate exosomes’ intercellular communicator role in the spread of misfolded proteins aiding the propagation of pathology. In this review, we discuss the potential contributions made by exosomes in progression of Alzheimer’s disease, Parkinson’s disease, and amyotrophic lateral sclerosis. Understanding contributions made by exosomes in pathogenesis of neurodegeneration opens the field for employing exosomes as therapeutic agents for drug delivery to brain since exosomes do cross the blood–brain barrier.

Exosomal miR-21-5p derived from bone marrow mesenchymal stem cells promote osteosarcoma cell proliferation and invasion by targeting PIK3R1.

Mesenchymal stem cells (MSCs) are a class of pluripotent cells that can release a large number of exosomes which act as paracrine mediators in tumour‐associated microenvironment. However, the role of MSC‐derived exosomes in pathogenesis and progression of cancer cells especially osteosarcoma has not been thoroughly clarified until now. In this study, we established a co‐culture model for human bone marrow‐derived MSCs with osteosarcoma cells, then extraction of exosomes from induced MSCs and study the role of MSC‐derived exosomes in the progression of osteosarcoma cell. The aim of this study was to address potential cell biological effects between MSCs and osteosarcoma cells. The results showed that MSC‐derived exosomes can significantly promote osteosarcoma cells’ proliferation and invasion. We also found that miR‐21‐5p was significantly over‐expressed in MSCs and MSC‐derived exosomes by quantitative real‐time polymerase chain reaction (qRT‐PCR), compared with human foetal osteoblastic cells hFOB1.19. MSC‐derived exosomes transfected with miR‐21‐5p could significantly enhance the proliferation and invasion of osteosarcoma cells in vitro and in vivo. Bioinformatics analysis and dual‐luciferase reporter gene assays validated the targeted relationship between exosomal miR‐21‐5p and PIK3R1; we further demonstrated that miR‐21‐5p‐abundant exosomes derived human bone marrow MSCs could activate PI3K/Akt/mTOR pathway by suppressing PIK3R1 expression in osteosarcoma cells. In summary, our study provides new insights into the interaction between human bone marrow MSCs and osteosarcoma cells in tumour‐associated microenvironment.

A review on the role of CAFs and CAF-derived exosomes in progression and metastasis of digestive system cancers.

Cancers evolve as a result of the accelerated proliferation of cancer cells in a complicated, enriched, and active microenvironment. Tumor microenvironment (TME) components are the master regulators of any step of cancer development. The tumor microenvironment is composed of many cellular and noncellular components that contribute to the evolution of cancer cells. Cancer-associated fibroblasts (CAFs) are activated fibroblasts in the TME that implicate in tumor progression and metastasis dissemination through secretion of oncogenic factors which are carried to the secondary metastatic sites through exosomes. In this review, we aimed to assess the role of CAF-derived exosomes in TME construction and pre-metastatic niche formation in different cancers of the digestive system in order to better understand some important mechanisms of metastasis and provide possible targets for clinical intervention. This review article is divided into two thematic parts explaining the general mechanisms of pre-metastatic niche formation and metastasis and the role of CAF-derived exosomes in different digestive system cancers including colorectal, gastric, esophageal, pancreatic, and liver cancers.

Exosomes in HIV infection.

Purpose of reviewThe exosomes play a critical role in HIV infection, which constitute a pathway to release intracellular material and exchange material and information between cells. Exosomes have become a hotspot in the field of AIDS research. This review introduces the formation process of HIV particles and exosomes, and summarizes the role of exosomes in the progression of HIV disease from multiple aspects.Recent findingsMany components of the exosomes involved in HIV transfer and replication affect the occurrence, development, and outcome of AIDS, and are closely related to HIV infection. Exosomes can have a dual impact on HIV infection, and play an important role in activating the latent reservoir of HIV and affecting the chronic inflammation of HIV. The biological information carried by exosomes is also of great significance for the prediction of HIV disease.SummaryThe present review summarizes the role of exosomes in HIV disease progression in various aspects in order to further understand the underlying mechanism affecting the infection and providing a new idea for the clinical diagnosis and treatment of AIDS.

Exosome-mediated transfer of CD44 from high-metastatic ovarian cancer cells promotes migration and invasion of low-metastatic ovarian cancer cells

ObjectiveTo investigate the detailed roles and mechanisms of tumor-derived exosomes in progression and metastasis of ovarian cancer in vitro.MethodsExosomes were isolated by differential centrifugation method; the morphology, size and biological markers of exosomes were separately defined by transmission electron microscopy, nanoS90 and Western blotting; Trans-well chambers assay was used to assess the ability of migration and invasion of recipient cells uptaking the exosomes from HO8910PM cells. The downstream molecule was screened by mass spectrometry.CD44 was identified by western blotting and the function of CD44 was identified by trans-well chambers assay and CCK8 assay.ResultsExosomes derived from HO8910PM cells could be transferred to HO8910 cells and promote cell migration and invasion in the recipient cells of ovarian cancer. And CD44 could be transferred to the HO8910 cells through exosomes from HO8910PM cells and influence the migration and invasion ability of HO8910 cells.ConclusionThe more aggressive subpopulation can transfer a metastatic phenotype to the less one via secreting exosomes within a heterogeneous tumor. CD44 may be a potential therapeutic approach for ovarian cancer.

Tumor-derived exosomal lnc-Sox2ot promotes EMT and stemness by acting as a ceRNA in pancreatic ductal adenocarcinoma.

Long noncoding RNAs (lncRNAs) or exosomes have recently been shown to play vital regulatory or communication roles in cancer biology. However, the roles and mechanisms of exosomal lncRNAs in tumor invasion or metastasis of pancreatic ductal adenocarcinoma (PDAC) remain unknown. In this study, we aimed to investigate the detailed roles and mechanisms of tumor-generated exosomes in progression and metastasis of PDAC in vitro and in vivo. We identified a lncRNA-Sox2ot from exosomes of highly invasive PDAC cells, and analyzed the expression of Sox2ot in the plasma samples and found that the plasma exosomal Sox2ot expression was high and correlated with TNM stage and overall survival rate of PDAC patients. Further research showed that Sox2ot promotes epithelial-mesenchymal transition (EMT) and stem cell like properties by regulating Sox2 expression. Sox2ot competitively binds to the miR-200 family to regulate the expression of Sox2, thus promoting invasion and metastasis of PDAC. We also confirmed the transmission of the exosomes from producer cells to recipient PDAC cells, exosomal Sox2ot can promote tumor invasion and metastasis in vitro and in vivo. We further confirmed tumor generated exosomes could excrete to tumor cell or blood circulation in vivo condition. Finally, we observed a decreased exosomal Sox2ot expression in postoperative blood samples of PDAC patients. The exosomal lncRNA Sox2ot plays important roles in tumor progression and may be a useful maker for pancreatic cancer prognosis.