Exosomes are produced by all cell types, their biogenesis is of endosomal origin, originating as a result of cell membrane invagination. Furthermore, physiochemical characteristics are important prerequisites for their commercial application. The representative size range of exosomes is 50-200 nm. Whereas, comparative to animal cell, exosomes from plant cell sources have a relatively larger size range, moreover, exhibit broader therapeutic potential. In this review study, we have briefly discussed the research potential of plant-derived exosomes. Including their earlier studies on biogenesis, characterization, isolation methods, and possible therapeutic applications. Additionally, we have quoted targeted drug delivery for targeted therapies and have provided insights of methods for customizing exosomes produced from plants with various drugs. Most-importantly, here we have embodied exosomes from plant sources are natural nano-inducers possessing the ability for inter-kingdom communication, resulting in cross-kingdom regulations.

Our study explores the role of cancer-derived extracellular exosomes (EXs), particularly focusing on collagen alpha-3 (VI; COL6A3), in facilitating tumor dissemination and metastasis in epithelial ovarian cancer (EOC). We found that COL6A3 is expressed in aggressive ES2 derivatives, SKOV3 overexpressing COL6A3 (SKOV3/COL6A3), and mesenchymal-type ovarian carcinoma stromal progenitor cells (MSC-OCSPCs), as well as their EXs, but not in less aggressive SKOV3 cells or ES2 cells with COL6A3 knockdown (ES2/shCOL6A3). High COL6A3 expression correlates with worse overall survival in EOC patients, as evidenced by TCGA and GEO data analysis. In vitro experiments showed that EXs from MSC-OCSPCs or SKOV3/COL6A3 cells significantly enhance invasion ability in ES2 or SKOV3/COL6A3 cells, respectively (both, P <0.001). In contrast, ES2 cells with ES2/shCOL6A3 EXs exhibit reduced invasion ability (p<0.001). In vivo, the average disseminated tumor numbers in the peritoneal cavity were significantly greater in mice receiving intraperitoneally injected SKOV3/COL6A3 cells than in SKOV3 cells (p<0.001). Furthermore, mice intravenously (IV) injected with SKOV3/COL6A3 cells and SKOV3/COL6A3-EXs showed increased lung colonization compared to mice injected with SKOV3 cells and PBS (p=0.007) or SKOV3/COL6A3 cells and PBS (p=0.039). Knockdown of COL6A3 or treatment with EXs inhibitor GW4869 or rapamycin-abolished COL6A3-EXs may suppress the aggressiveness in EOC.

Exosomes, a subset of extracellular vesicles, have emerged as pivotal mediators of intercellular communication, revolutionizing our comprehension of cellular interactions. Their diverse cargo, comprising proteins, nucleic acids, and bioactive molecules, plays a crucial role in various physiological and pathological processes. In the intricate landscape of adult neurogenesis, exosomes wield significant influence, actively participating in the generation of new neurons within the adult mammalian brain. Originating predominantly from non-niche cells, these vesicles contribute substantially to the regulation of neuroinflammation, thereby impacting neurogenesis and offering therapeutic promise for neurological disorders. In the specific context of Parkinson's disease (PD), exosomes assume a multifaceted role, prominently implicated in the propagation of α-synuclein oligomers and the orchestration of neuroinflammation. Stem cell-derived exosomes present themselves as promising therapeutic agents, capable of reshaping the microenvironment, repairing neuronal damage, and mitigating apoptosis. The ongoing exploration of exosomes continues to unravel intricate biological processes, paving the way for innovative medical interventions and treatments, particularly within the challenging landscape of neurodegenerative diseases such as PD. The comprehensive understanding of exosomal functions holds the potential to advance our therapeutic approaches, offering new avenues for intervention and treatment strategies in the realm of neurodegenerative disorders.

The adipose tissue is responsible for fat storage and is the major producer of exosomes. Biological content transported by the exosomes provides information, such as immunometabolic alterations. This study aimed to isolate whole exosomes from plasma and supernatant of differentiated 3T3-L1 cells using three isolation techniques. Plasma from 120 individuals categorized by body adipose tissue proportion and differentiated 3T3-L1 cells were used in this study. The exosome isolation techniques were differential centrifugation (DC), size exclusion chromatography (SEC), and a commercial kit (Invitrogen), and characterized by cryo-TEM, TEM, and western blot for the tetraspanins CD9 and CD81. In the three isolation techniques, cryo-TEM and TEM analysis showed similar quality, quantity, and morphology of exosomes; at the same time, no difference was observed between individuals categorized by proportion of body fat. According to our results, the concentration of the circulating exosomes is not different between normal and high-fat percentage individuals, but rather their composition. The SEC and kit commercial proved that compile with most of the advantages of an exosome isolation technique, nerveless we emphasize the importance of selecting the appropriate methodology depending on the specific research objectives.

Cancer remains one of the main causes of death in the world due to its increasing incidence and treatment difficulties. Although several progresses have been done in this field, innovative approaches are needed to reduce tumor incidence, progression and spreading. In particular, the development of cancer vaccines is currently ongoing like both preventive and therapeutic strategy. This concept is not new, but few vaccines have been approved in oncology. Antigen-based vaccination emerges as a promising strategy, leveraging specific tumor antigens to activate the immune system response. However, challenges persist in finding suitable delivery systems and antigen preparation methods. Exosomes (EXs) are highly heterogeneous bilayered vesicles which carry several molecule types in the extracellular space. The peculiarity is that they may be released from different cells and may be able to induce a direct or indirect stimulation of immune system. In particular, EX-based vaccines may cause anti-tumor immune attack or produce memory cells recognizing cancer antigens and inhibit disease appearance. This review delves into EXs composition, biogenesis, and immune-modulating properties exploring their role as tool for prevention and therapy in solid tumors. Finally, here we describe future research directions to optimize vaccine efficacy and realize the full potential of EX-based cancer immunotherapy.

Preeclampsia (PE) is a serious complication of pregnancy with a pathogenesis that is not fully understood, though it involves the impaired invasion of extravillous trophoblasts (EVTs) into the decidual layer during implantation. Recently, others have found that diverse cell types, including EVTs, produce exosomes filled with molecular cargo (mainly proteins and RNAs) that can be transported to other cells and organs both locally and long-range. The cargo delivered by exosomes can signal to and modify the receiving cells and their environment, and EVT-derived exosomes may influence the pathogenesis of PE. Because the risk of PE is actually decreased by cigarette smoking, we considered the possibility that nicotine, a critical component of tobacco smoke, might protect against PE by modifying the content of exosomes from EVTs. In this study, we applied nicotine stimulation to cultured EVTs and subjected their secreted exosomes to proteomic analysis. We identified many proteins whose abundance in exosomes was modified by nicotine treatment of the donor EVTs, and we used bioinformatic annotation and network analysis to select five key hub proteins with potential roles in the pathogenesis or prevention of PE.

Subarachnoid hemorrhage (SAH) is most commonly seen in patients over 55 years of age and often results in a loss of many productive years. SAH has a high mortality rate, and sur-vivors often suffer from early and secondary brain injuries. Understanding the pathophysiology of the SAH is crucial to identifying potential therapeutic agents. One promising target for diagno-sis and prognosis of SAH is circulating microRNAs, which regulate gene expression and are in-volved in various physiological and pathological processes. In this review, we discuss the poten-tial of microRNAs as a target for diagnosis, treatment, and prognosis in SAH.

Background: diabetic nephropathy (DN) is a serious complication of diabetes mellitus and a common cause for end stage renal disease. Autophagy has a defensive role against kidney damage caused by hyperglycemia. The mesenchymal stem cells (MSCs) derived exosomes are currently considered as a new promising therapy in chronic renal injury. However, the renal protective mechanism of exosomes on DN has not been completely understood. We examined the potential role of MSCs derived exosomes in enhancement of autophagy activity and its effect on DN. In our study we used five groups of rats; control, DN, DN treated with exosomes, DN treated with 3-methyladenine (3-MA) and chloroquine (inhibitors of autophagy) and DN treated with 3-methyladenine (3-MA) and chloroquine and exosomes groups. We assessed renal functions, morphology and fibrosis. Moreover, autophagy markers; mTOR, Beclin-1, light chain-3 (LC3-II), and LC3-II/LC3-I ratio were detected. Additionally, electron microscopy was used for detection of autophagosomes. Results: Exosomes markedly improved the renal functions and showed histological restoration of renal tissues with significant increase in LC3 and Beclin-1 besides the significant decrease in mTOR and fibrotic markers expression in renal tissue. All previous effects were partially abolished by the autophagy inhibitor, chloroquine and 3-MA. Conclusions: we conclude that autophagy induction by exosomes could attenuate DN in a rat model of streptozotocin-induced diabetes mellitus.

Tumor-associated macrophages are a key component in the tumor microenvironment, secreting extracellular vesicles (EVs) such as exosomes and other various factors for intercellular communication. However, macrophage-derived EVs heterogeneity and their cytotoxicity to cancer cells has not been well understood. Here, we aimed to separately isolate various types of macro-phage-EVs by size exclusion chromatography (SEC) method and investigate EV transmission and cytotoxicity to oral cancer cells. For fluorescence-labeling of cellular and EV membranes, palmitoylation signal-fused GFP and tdTomato were expressed in THP-1 monocytic cells and HSC-3 oral cancer cells, respectively. We found that fluorescence-labeled EVs secreted by macrophages were highly transmissive to oral cancer cells than those from parental monocytic cells. In a co-culture system and conditioned medium (CM), a macrophage-secreted unidentified factor was cytotoxic to oral cancer cells. We fractionated macrophage-derived EVs by the SEC method and performed western blotting to characterize various EV types. Three fractions were characterized: small exosomes (EXO-S: < 50 nm) fraction containing HSP90α, HSP90β, CD63 (EV marker) and β-actin; large exosomes (EXO-L: 50-200 nm) fraction containing CD9 (EV marker) and HSP90β; large EVs (100-500 nm) fraction. Notably, the macrophage-derived small exosomes fraction was cytotoxic to oral cancer cells, while large exosomes and large EVs were not. There-fore, it was implicated that macrophage-derived small exosomes are cytotoxic with high trans-mission potential to cancer cells.

It has been widely established that the characterization of extracellular vesicles (EVs), particularly small EVs (sEVs), shed by different cell types into biofluids, helps identify biomarkers and therapeutic targets in neurological and neurodegenerative diseases. Recent studies are also exploring the efficacy of mesenchymal stem cell-derived extracellular vesicles naturally enriched with therapeutic microRNAs and proteins for treating various diseases. Besides, EVs released by various neural cells play a crucial function in the modulation of signal transmission in the brain in physiological conditions. However, in pathological conditions, such EVs can facilitate the spread of pathological proteins from one brain region to the other. On the other hand, analysis of EVs in biofluids can identify sensitive biomarkers for diagnosis, prognosis, and disease progression. This review discusses the potential therapeutic use of stem cell-derived EVs in several central nervous system diseases. It lists their differences and similarities and confers various studies exploring EVs as biomarkers. Further advances in EV research in the coming years will likely lead to the routine use of EVs in therapeutic settings.

Stroke is the number one cause of morbidity in the United States and number two cause of death worldwide. There is a critical unmet medical need for more effective treatments of ischemic stroke, and this need is increasing with the shift in demographics to an older population. Recently, several studies have reported the therapeutic potential of stem cell derived exosomes as new candidates for cell-free treatment in stoke. This review focuses on the use of stem cell-derived exosomes as a potential treatment tool for stroke patients. Therapy using exosomes can have a clear clinical advantage over stem cell transplantation in terms of safety, cost, and convenience, as well as reducing bench-to-bed latency due to fewer regulatory milestones. In this review article, we focus on 1) the therapeutic potential of exosomes in stroke treatment, 2) the optimization process of upstream and downstream production, and 3) preclinical application in stroke animal model. Finally, we discuss the limitations and challenges faced by exosome therapy in future clinical applications.

This review focuses on the role of small extracellular vesicles in the pathophysiological mechanisms of retinal degenerative diseases. Many of these mechanisms are related or modulated by the oxidative burden of the retinal cells. It has been recently demonstrated that cellular communication in the retina involves extracellular vesicles and that their rate of release and cargo features might be affected by the cellular environment and in some instances also mediated by autophagy. The fate of these vesicles is diverse, and could end up in the circulation and be used as markers, or target neighbour cells modulating gene and protein expression and eventually also angiogenesis. Neovascularization in the retina promotes vision loss in diseases such as diabetic retinopathy and age-related macular degeneration. The importance of micro RNAs, either as small extracellular vesicles’ cargo or free circulating, on the regulation of retinal angiogenesis is also discussed.

Pediatric brain tumors are the leading cause of cancer-related death in children. Diagnosis cur-rently relies on surgical biopsy to obtain tumor tissue for histological analysis. There is a great need for less invasive approaches to molecularly profile tumors and monitor therapeutic response. Liquid biopsy analysis of circulating tumor biomarkers in biofluids like cerebrospinal fluid (CSF) and blood offers a promising minimally invasive strategy. This review discusses recent advances in developing liquid biopsy assays using next-generation sequencing, digital PCR, and emerging techniques to detect circulating tumor DNA (ctDNA), cells (CTCs), and exosomes in pediatric brain tumors. The ability to use these circulating biomarkers for non-invasive diagnosis, thera-peutic targeting, tracking response to therapy, and understanding resistance mechanisms is ex-amined. Technical and clinical validation challenges to translate liquid biopsies into routine clin-ical practice are also discussed.

Background: Chronic Obstructive Pulmonary Disease (COPD) and Idiopathic Pulmonary Fibrosis (IPF) are chronic, progressive lung ailments which are characterized by distinct pathologies. Early detection biomarkers and disease mechanisms for these debilitating diseases are lacking. Exosomes are small extracellular vesicles attributed to carry proteins, mRNA, miRNA and sncRNA to facilitate cell-to-cell communication under normal and diseased conditions. Exosomal miRNAs have been studied in relation to many diseases. However, there is little to no knowledge regarding the miRNA population of BALF or the lung tissue derived exosomes in COPD and IPF. Here, we determined and compared the miRNA profiles of BALF and lung tissue-derived exosomes from healthy non-smokers, healthy smokers, and patients with COPD and IPF in independent cohorts. Results: Exosome characterization using NanoSight particle tracking and TEM demonstrated that the BALF-derived exosomes were approximately 89.85 nm in size and ~2.95 X 1010 particles/mL. Lung-derived exosomes were ~146.04 nm in size and ~2.38 X 1011 particles/mL. NGS results identified three differentially expressed miRNAs in the BALF, while one in the lung-derived exosomes from COPD patients as compared to healthy non-smokers. Of these, three- and five-fold downregulation of miR-122-5p amongst the lung tissue-derived exosomes from COPD patients as compared to healthy non-smokers and smokers, respectively. Interestingly, there were key 55 differentially expressed miRNAs in the lung tissue-derived exosomes of IPF patients compared to non-smoking controls. Conclusions: Overall, we identified specific miRNAs to develop as biomarkers or targets for pathogenesis of these chronic lung diseases.

Extracellular vesicles (EVs) present a great potential for the development of new treatments in the biomedical field. To be used as therapeutics, many different sources have been used for EVs obtention, while only few studies have addressed the use of platelet derived EVs (pEVs). In fact, pEVs have been shown to intervene in different healing responses, thus some studies have evaluated their regenerative capability in wound healing or hemorrhagic shock. Even more, pEVs have proven to induce cellular differentiation, enhancing musculoskeletal or neural regeneration. However, the obtention and characterization of pEVs is widely heterogeneous and differs from the recommendations of the International Society for Extracellular Vesicles. Therefore, in this review, we aim to present the main advances in the therapeutical use of pEVs in the regenerative medicine field while highlighting the isolation and characterization steps followed. The main goal of this review is to portray the studies performed in order to enhance the translation of the pEVs research into feasible therapeutical applications.

Urinary bladder cancer (UBC) is the most common malignancy of the urinary tract in humans, with an estimated global prevalence of 1.1 million cases over 5 years¹. Due to high rates of recurrence and resistance to chemotherapy, UBC is one of the most expensive cancers to treat, resulting in significant health care costs. There is, therefore, a critical need to develop innovative molecular and cellular tools to refine patient stratification and help predict response to treatment. Urine is an underused resource of biological components shed from bladder tumors, such as exfoliated cells and extracellular vesicles, that could serve as molecular fingerprints and provide valuable biological insights into tumor phenotype and mechanisms of resistance to chemotherapy. Additionally, characterization of urine-derived extracellular vesicles and cells could be used as reliable biomarkers for prediction of response to neoadjuvant therapy.

T-cell mediated immune responses should be regulated to avoid the development of autoimmune or chronic inflammation diseases. Several mechanisms have been described to regulate this process, namely death of overactivated T cells by cytokine deprivation, suppression by T regulatory cells (Treg), induction of expression of immune checkpoint molecules such as CTLA-4 and PD-1, or activation-induced cell death (AICD). In addition, activated T cells release membrane microvesicles called exosomes during these regulatory processes. In this review, we revise the role of exosome secretion in the different pathways of immune regulation described to date and its importance in the prevention of autoinmune disease. Expression of membrane-bound death ligands on the surface of exosomes during AICD, or the more recently described transfer of miRNA or even DNA inside T-cell exosomes are molecular mechanisms that will be analyzed.

Colorectal cancer (CRC) is one of the most commonly diagnosed malignancies with a high incidence and mortality. An essential challenge in colorectal cancer management is to identify new prognostic factors that could better estimate the evolution and treatment responses of this disease. Considering their role in cancer development, progression and metastasis, miRNAs have become an important class of molecules suitable for cancer biomarkers discovery. We performed a systematic search of studies investigating the role of miRNAs in colorectal progression and liver metastasis, published until October 2018. In this review, we present up-to-date information regarding the specific microRNAs involved in CRC development, considering their roles in alteration of Wnt/βcatenin, EGFR, TGFβ and TP53 signaling pathways. We also emphasize the role of miRNAs in controlling the epithelial-mesenchymal transition of CRC cells, a process responsible for liver metastasis in a circulating tumor cell-dependent manner. Furthermore, we discuss the role of miRNAs transported by CRC-derived exosomes in mediating liver metastases, by preparing the secondary pre-metastatic niche and in inducing liver carcinogenesis in a Dicer-dependent manner.

Melasma is a challenging skin condition which involves both structural and functional skin alterations. Despite the availability of various treatment options, the management remains complex. This is the first study to investigate topical application of Rosa Damascena stem cell exosomes when used concomitantly with microneedling in women and men with facial melasma. We recruited 20 subjects with Fitzpatrick skin types I-III, exhibiting melasma of varying severity. The modified Melasma Area and Severity Index (mMASI) and Global Aesthetic Improvement Scale (GAIS) were utilized to evaluate treatment response. The treatment protocol involved microneedling followed by exosome application over four or five sessions, at 4-week intervals. Ninety percent of subjects demonstrated a significant improvement in mMASI scores, while only 10% showed no change. GAIS assessment further supports overall improvement, with just 10% categorized as "not changed". Tolerability was favorable, with mild, transient side effects. Our findings suggest promising outcomes with this combined therapy, underscoring its potential as a safe and effective approach for treating melasma, particularly in severe and moderate cases. However, further research with larger sample sizes and control arms is warranted to validate these findings and explore long-term efficacy.

Diabetes and diabetes-induced micro and macrovascular complications are major causes of healthcare problems. The extracellular vesicles are produced by all cells from all organisms. They are shown to have properties of the producer cells and also reflect the host physiology and pathology. Since the EVs represent the cellular state they are excellent biomarkers. In this review, we will focus on the EVs produced by the Neuro Vascular Unit cells of the eye as well as the extraocular cells in the onset and progression of diabetic retinopathy. A brief account of the use of these nanovesicles in personalised medicine is also given.

In the last decades, it has been established that astrocytes play key roles in the regulation of neuronal morphology. However, the contribution of astrocyte-derived small extracellular vesicles (sEVs) to morphological differentiation of neurons has only recently been addressed. Here, we showed that cultured astrocytes expressing a GFP tagged version of the stress-regulated astrocytic enzyme Aldolase C (Aldo C-GFP) release small extracellular vesicles (sEVs) which are transferred into cultured hippocampal neurons. Surprisingly, Aldo C-GFP-containing sEVs (Aldo C-GFP sEVs) displayed an exacerbated capacity to reduce the dendritic complexity in developing hippocampal neurons compared to sEVs derived from control (i.e. GFP-expressing) astrocytes. Using bioinformatics and biochemical tools, we found that the total content of overexpressed Aldo C-GFP correlates with an increased content of endogenous miRNA-26a-5p in both total astrocyte homogenates and sEVs. Notably, neurons magnetofected with a nucleotide sequence that mimics endogenous miRNA-26a-5p (mimic 26a-5p) not only decreased the levels of neuronal proteins associated to morphogenesis regulation and also reproduced morphological changes induced by Aldo-C-GFP sEVs. Furthermore, neurons magnetofected with a sequence targeting miRNA-26a-5p (antago 26a-5p) were largely resistant to Aldo C-GFP sEVs. Our results support a novel and complex level of astrocyte-to-neuron communication mediated by astrocyte-derived sEVs and the activity of their miRNA content.

MFGE8 is a major exosome (EV) protein known to mediate inflammation and atherosclerosis in type 2 diabetes mellitus (T2DM) in animal studies. However, its role in the pathophysiology of human T2DM, obesity, and cardiovascular disease has been controversial and less explored. Earlier, we reported a rare Asian Indian population-specific missense variant (rs371227978; Arg148His) in the MFGE8 associated with increased circulating Mfge8 and T2DM. Here, we have further investigated the role of Mfge8 with T2DM risk in additional Asian Indians (n=4917) and Europeans and other multiethnic cohorts from UK Biobank (UKBB) (n= 455,808) and the US (n=1150). We also evaluated the exposure of Mfge8-enriched human EVs (with and without mutation) in zebrafish (ZF) for their impact on the cardiometabolic organ system. Most individual carriers of Arg148His variant not only had high circulating Mfge8 but also showed a positive significant correlation with glucose (r= 0.42; p = 4.9x10-04), while the non-carriers showed a negative correlation of Mfge8 with glucose (r = -0.38; p = 0.001) in Asian Indians. However, the same variant was monomorphic in Europeans and other ethnic groups of UKBB and US cohorts. Even in the absence of Arg148His variant, serum Mfge8 correlated significantly with blood glucose both in Caucasians (r = 0.56; p = 8.4x10-10) and individuals from other ethnicities (African Americans, Hispanics, and others) (r = 0.31; p = 5.8x10-4). Since Mfge8 is an EV marker, the exposure of Mfge8-enriched human EVs to ZF larvae rapidly developed fatty liver disease and heart hypertrophy and exhibited redundant growth with poor muscular architecture with and without the high-fat diet (HFD), while the control group fishes developed fatty liver disease and heart hypertrophy only after the HFD feeding. With strong evidence from animal studies supporting the role of Mfge8 in obesity, insulin resistance, and the development of atherosclerosis in T2DM, the current research suggests that circulating Mfge8 may be a potential marker for preventing or reducing the risk of T2DM and cardiovascular disease.

Developing a biomolecular detection method that minimizes photodamage while maintaining an environment suitable for biological constituents to maintain their physiological state is expected to drive new diagnostic and mechanistic breakthroughs. In addition, ultra-sensitive diagnostic platforms are needed for rapid and point-of-care technologies for various diseases. Considering this, surface-enhanced Raman scattering (SERS) is proposed as a non-destructive and sensitive approach to address the limitations of fluorescence, electrochemical, and other optical detection techniques. However, to advance the applications of SERS, novel approaches to enhance the signal of substrate materials are needed to improve reproducibility and costs associated with manu-facture and scale-up. Due to their physical properties and synthesis, semiconductor-based nanostructures have gained increasing recognition as SERS substrates; however, low signal en-hancements have offset their widespread adoption. To address this limitation and assess the po-tential for use in biological applications, zinc oxide (ZnO) was coated with different concentra-tions (0.01-0.1 M) of gold (Au) precursor. When crystal violet (CV) was used as a model target with the synthesized substrates, the highest enhancement was obtained with ZnO coated with 0.05 M Au precursor. This substrate was subsequently applied to differentiate exosomes derived from three cell types to provide insight into their molecular diversity. We anticipate this work will serve as a platform for colloidal hybrid SERS substrates in future bio-sensing applications.

Extracellular vesicles (EVs) are enclosed by a lipid-bilayer membrane and secreted by all types of the cells under various physiological conditions. EVs play important roles in intercellular communication and crosstalk between tissues in the body. They are classified into three groups, such as apoptotic bodies, microvesicles, and exosomes. Exosomes were isolated from biofluids including blood, urine, milk, and cell culture media. Exosomes have significant potential for drug delivery and diagnosis. However, the method of isolation affects the physical and biological properties of exosomes. Several methods based on different principles have been developed for exosome isolation. These include ultrafiltration, precipitation, ultracentrifugation, size-exclusion chromatography, and microfluidics. In this study, we applied three common methods, such as ultrafiltration, precipitation, and ultracentrifugation, to isolate exosomes from the cell culture medium and investigated the effects of these different isolation methods on the size distribution and quality of the isolated exosomes. Field emission scanning electron microscopy (FESEM) images, size distribution, total protein content, and the effect of exosomes on the viability of hypoxic cells were analyzed in this study. The analysis revealed that compared to other methods, the ultracentrifugation method can isolate exosomes with smaller diameter (ranging from 20 to 80 nm), lower total protein content (50 µg/ml), and causing the increased viability of the hypoxic cells. The precipitation method does not require special equipment and is inexpensive, if the quality and purity of this method are solved, and it can be used as the best method for exosome isolation. This study can serve as a guide for choosing the best exosome isolation method for applications in medicine according to the needs, time, cost, and equipment.

Chronic Traumatic Encephalopathy (CTE) is a neurodegenerative disease consistently associated with repetitive traumatic brain injuries (TBIs), which makes multiple professions, such as contact sports athletes, especially susceptible to its onset. There are currently no approved biomarkers to diagnose CTE, thus it can only be confirmed through a post-mortem brain autopsy. Several imaging and cerebrospinal fluid biomarkers have shown promise in the diagnosis. However, blood-based biomarkers can be more easily obtained and quantified, increasing their clinical feasibility and potential for prophylactic use. This article aimed to comprehensively review the studies into potential blood-based biomarkers of CTE, discussing common themes and limitations as well as suggesting future research directions. While the interest in blood-based biomarkers of CTE has recently increased, the research is still in its early stages. The main issue for many proposed biomarkers is their lack of selectivity for CTE. However, several molecules, such as tau phosphorylated on different epitopes, were able to discern CTE from different neurodegenerative diseases. Further, results from studies of exosomal biomarkers suggest that exosomes are a promising source of biomarkers reflective of the internal environment of the brain. Nonetheless, more longitudinal studies combining imaging, neurobehavioral and biochemical approaches are warranted to establish robust biomarkers of CTE.

Macrophages are the key effector cells of innate immunity which show two polarized states: M1, classically activated and M2, alternatively activated. Tumor-associated macrophages (TAMs) which usually show M2 polarization, are immunosuppressive cells that enhance tumor metastasis and invasion. Also, enrichment of TAMs is known to be closely associated with poor prognosis of cancer patients. Therefore, TAMs are considered to be promising targets for immunotherapy. Importantly, tumor-derived exosomes emerged as a crucial player in immune regulation which can remodel the tumor microenvironment towards immunosuppressive state. Of note, few studies have shown that exosomes could induce polarization of macrophages towards M2 type in tumor condition, while others showed activation of M1 or mixed phenotype. Considering the role of TAMs in cancer, there is an urgent need to decipher the exosome-mediated cross-talk between tumor cells and macrophages.For this, we used murine model of Dalton’s lymphoma (DL), wherein, firstly, we evaluated increased exosome burden by assessing exosome level in serum as well as in various tissues of tumor-bearing host. Next, proteomic profiling of lymphoma-derived exosomes was done which revealed the presence of immunomodulatory proteins. Of note, these proteins were known to alter the macrophage polarization. In order to assess the effect of these exosomes on macrophages, we performed in vitro study using RAW264.7 cells. In vitro study revealed that frequent uptake of exosomes mediated a morphological change in macrophages which reduced their phagocytic activity. In parallel, exosomes increased reactive oxygen species (ROS) level and inhibited LPS-induced nitric oxide (NO) level in macrophages. Also, exosomes upregulated the expression of arginase-1 (an M2 marker) in macrophages but decreased the LPS-induced nitric oxide synthase 2 (NOS2) (an M1 marker) expression. Moreover, we observed a pro-tumoral cytokine profile in macrophages incubated with exosomes. Our study suggests that exosome load increases in lymphoma-bearing hosts systemically. Importantly, lymphoma-derived exosomes mediate the activation of macrophages towards pro-tumoral M2 type. Our results give an insight into the exosome-mediated tumor and immune cell cross-talk which could serve as an important prospect for targeting in cancer immunotherapy.

Alzheimer´s Disease (AD) has currently no effective treatment; however, preventive measures can significantly delay the progress/onset of the disease. Thus, accurate and early prediction of risk is an important strategy to alleviate the AD burden. Neuroinflammation is a major factor prompting the onset of the disease. Inflammation exerts its toxic effect via multiple mechanisms. Amongst others, it is affecting gene expression via modulation of non-coding RNAs (ncRNAs), such as miRNAs. Recent evidence supports that inflammation can also affect long non-coding RNAs (lncRNAs) expression. While the association between miRNAs and inflammation in AD has been extensively studied, the role of lncRNAs in neurodegenerative diseases has been less explored. In this review, we focus on lncRNAs and inflammation in the context of AD. Furthermore, since plasma-isolated extracellular vesicles (EVs) are increasingly recognized as an effective monitoring strategy of brain pathologies, we have focused on the studies reporting dysregulated lncRNAs in EVs isolated from AD patients and controls. The revised literature shows a positive association between pro-inflammatory lncRNAs and AD. However, the reports evaluating lncRNAs alterations in EVs isolated from plasma of patients and controls, although still limited confirm the value of specific lncRNAs associated with AD as reliable biomarkers. This is an emerging field that will open new avenues to improve risk prediction, patients’ stratification and may lead to the discovery of potential novel therapeutic targets for AD

Recent years brought great focus in the field of development of extracellular vesicles (EVs) based drug-delivery systems. Considering possible applications of EVs as a drug carriers the isolation process is a crucial step. To solve problems related with EV isolation, we created and validated a new EVs isolation method – Low Vacuum Filtration (LVF) and compared it with two commonly applied procedures - differential centrifugation (DC) and ultracentrifugation (UC). EVs isolated from endothelial cells culture media have been characterized by a) transmission electron microscopy (TEM) b) nanoparticle tracking analysis (NTA), c) western blot and d) Fourier-Transform Infrared Spectroscopy (FTIR). Additionally, the membrane surface have been imaged with Environmental Scanning Electron Microscopy (ESEM). We showed that LVF is reproducible and efficient method for EVs isolation form conditioned media. Additionally, we observed correlation between ATR-FTIR spectra quality and the EVs and proteins concentration. ESEM imaging confirmed that actual pore diameter are close to the values calculated theoretically. LVF method is an easy, fast and inexpensive EVs isolation method which allows for isolation of both ectosomes and exosomes from high volume sources with good repeatability. We think that it could be an efficient alternative for commonly applied methods.

The lymphocyte function–associated antigen-1 (LFA-1) (also CD11a/CD18 and αLβ2), is just one of many integrins in the human body, but its significance derives from its exclusive presence in leukocytes. In this review, we summarize the studies relating LFA-1 and its major ligand ICAM-1 (CD54) with cancer, through the function of lymphocytes and myeloid cells on tumor cells. We consider how LFA-1 mediates the interaction of leukocytes with tumors and the role of ICAM-1 in tumor dynamics, which can be independent of its interaction with LFA-1. A more detailed examination of LFA’s role within B-cell chronic lymphocytic leukemia is made. Finally, we discuss the role of LFA-1-harboring exosomes in tumor growth and metastasis.

Cancer is a complex and heterogeneous disease, influenced by various factors that affect its progression and response to treatment. Although histopathological diagnosis is crucial for identifying and classifying cancer, it may not accurately predict the disease's development and evolution in all cases. To address this limitation, liquid biopsy has emerged as a valuable tool, enabling a more precise and non-invasive analysis of cancer. Liquid biopsy offers the ability to detect tumor DNA fragments, circulating tumor cells, and exosomes released by cancer cells into the bloodstream. Exosomes, in particular, have attracted significant attention in cancer research due to their specific protein composition, which can provide valuable insights into the disease. The protein profile of exosomes often differs from that of normal cells, reflecting the unique molecular characteristics of cancer. Analyzing these proteins can help identify cancer-associated markers that play critical roles in tumor progression, invasion, and metastasis. Ongoing research and clinical validation are essential to advance and effectively utilize protein biomarkers in cancer. Nevertheless, their potential to improve diagnosis and treatment is highly promising. This review discuss several exosome proteins of interest in breast cancer, particularly focusing on studies conducted in mammary tissue and cell lines in humans and experimental animals. Unfortunately, the studies conducted in the canine species are scarce. This emphasis sheds light on the limited research available in this field. Additionally, we present a curated selection of studies that have explored exosomal proteins as potential biomarkers, aiming to achieve the aforementioned benefits in breast cancer diagnosis, prognosis, monitoring, and treatment.

Exosomes have shown promising potential as a therapeutic approach for wound healing. Nevertheless, the translation from experimental studies to commercially available treatments is still lacking. To assess the current state of research in this field, a systematic review was performed to examine the methodological heterogeneity among studies conducted over the past five years. Additionally, the review analyzed the suitability of animal models used and their relevance to human medicine. A PubMed search was performed for english-language, full-text available papers published from 2018 to June 2023, focusing on exosomes derived from mammalian sources and their application in wound healing, particularly those involving in vivo assays. Out of 531 results, 148 papers were selected for analysis. The findings revealed significant variability in terms of cell sources and types, biomaterials, and administration routes under investigation, indicating the need for further research in this field. Additionally, a comparative examination encompassing diverse cellular origins, types, administration pathways, or biomaterials is imperative. Furthermore, the predominance of rodent-based animal models raises concerns, as there have been limited advancements towards more complex in vivo models and scale-up assays. These constraints underscore the substantial efforts that remain necessary before attaining commercially viable and extensively applicable therapeutic approaches using exosomes.

MicroRNAs (miRNAs) within the exosomes are short non-coding RNAs that are associated with many diseases including cancers and are crucial players in regulating gene expression and regula-tion. Owing to their potential role as emerging biomarkers, efficient isolation, and quantification methods of miRNA from the exosomes in the cell’s supernatant are complicated and challenging. The quantitative PCR method is the gold standard for miRNA identification and estimation. Nucleic acid-based assays are expensive, labour-intensive, and require expertise. In this work, we demon-strated an aptamer-based magnetic separation of the exosomes, and quantification of the miRNA using a fluorescence switching assay. The fluorescence assay relies on the fluorescence of the fluorophore labelled cDNA quenched by carbon nanomaterials coated on magnetic beads (OFF state). When the target miRNA210 is introduced to the system, the cDNA detaches from the quenching surface. As a result, the fluorescence intensity increases (ON state) with increasing miRNA concentration within the dynamic range of 0-100 nM. This method can detect miR210 as low as 5 pM. This method does not exhibit any cross-reactivity with other closely related miRNAs. The method was validated by spiking miRNA with the standard RT-PCR method using SYBR green as a fluorescent probe. This method can be used for the minimally invasive detection of cancer biomarkers in breast cancer patients.

Using a combination of pan proteomic platform associated with systemic biology analyses, we demonstrate that neonatal microglial cells derived from cortex and spinal cord expressed different phenotypes upon the physiological or pathological conditions. They also highlight great variability in protein production on both cellular and exosome levels. Bioinformatics data indicate for the cortical microglia anti-inflammatory and neurogenesis/tumorigenesis characteristics, while for the spinal cord microglia involvement in the inflammatory response. We confirmed these results by performing functional testing including neurite outgrowth assays in DRGs cell line, and glioma proliferation analysis in 3D spheroid cultures. Results from these in vitro assays indicate that the microglia located at different CNS areas reveal differential biological functions. While both microglia sources enhanced growth of DRGs axons, only the spinal microglia significantly attenuated glioma proliferation. Overall these findings are pointing to the fact that the origin of neonatal microglia affects the physio-pathological function, which may address the prevalence of the glioma in the brain in comparison with the spinal cord in adult.

Here we first report, how cholera toxin (CT) A subunit (CTA), the bacterial enzyme moiety responsible of cell signaling alteration, can take over the exosomal pathway, spread extracellularly and be transmitted in a cell population. A first evidence for long-term transmission of CT toxic effect via extracellular vesicles was obtained in CHO cells. To follow CT intracellular route towards exosome secretion we adopted a strategy apt to convert multivesicular body (MVB) derived exosomes in traceable fluorescent vectors. CT treated Me665 cells, a human melanoma cell line highly expressing caveolin-1 (Cav-1) and GM1, were used to purify and characterize fluorescent exosomes. Our results clearly show association of CT with exosomes together with typical exosomal markers and the HSP90 and PDI molecules, the required membrane translocation elements of CTA to the cytoplasm. Confocal microscopy proved direct CT containing fluorescent exo transfer into CHO cells coupled with the morphological cell change characteristic of CT action. Moreover, direct assessment of cAMP levels in Me665 cells treated with CT containing exo showed an efficient induction of cAMP increase comparable with CT alone. From our results, we can infer that CT can exploit exosome-mediated cell communication to target and extend its pathophysiological action throughout cell tissues.

To verify the efficacy of placental extracts (Pla-Ext) and human mesenchymal stem-cell-derived exosomes (hMSC-Exo) against human skin aging, we investigated the human dermal fibroblast (HDF) response following hMSC-Exo and Pla-Ext treatment and whether they elicited resistance to damage when HDFs were subjected to several types of aging stresses. The effect of hMSC-Exo alone, the combined effect of Pla-Ext and hMSC-Exo, and the effect of hMSC-Exo (Pla/MSC-Exo) recovered from cultures with Pla-Ext added to hMSC were verified using collagen, elastin, and hyaluronic acid synthase mRNA levels for each effect. Cells were subjected to photoaging (UV radiation), glycation (glycation end product stimulation), and oxidation (H2O2 stimulation) as HDF stressors. Pla-Ext did not significantly affect normal skin fibroblasts considering intracellular parameters; however, a pro-proliferative effect was observed. Pla-Ext induced resistance to several stresses in skin fibroblasts (UV irradiation, glycation stimulation, H2O2 stimulation) and inhibited reactive oxygen species accumulation following H2O2 stimulation. Although the combined efficacy of hMSC-Exo and Pla-Ext was unclear, some changes resulted in senescence stress resistance due to preconditioned hMSC-Exo stimulated by Pla-Ext. This suggests that Pla-Ext supplementation may cause some changes in the surface molecules or hMSC-Exo content (e.g., microRNA).

Bladder cancer (BC) diagnosis is reliant on cystoscopy, an invasive procedure associated with urinary tract infections. This has sparked interest in identifying non-invasive biomarkers in body fluids such as blood and urine. A source of biomarkers in these biofluids are extracellular vesicles (EVs), nanosized vesicles that contain a wide array of molecular cargo, including small non-coding RNA such as microRNA and transfer RNA-derived fragments (tRF). Here we performed small-RNA next-generation sequencing for urine EVs, serum EVs and serum supernatant from 41 patients with non-muscle invasive BC (27 stage Ta, 14 stage T1) and 15 non-cancer patients (NCP) with benign cystoscopy findings. Serum and urine samples were collected before transurethral resection of bladder tumors (TUR-b) and at routine postsurgery check-ups. Expression levels of tRFs in presurgery samples were compared to those at postsurgery check-ups and to NCPs. To strengthen the reliability of our results, samples from 10 patients with stage T1 disease were resequenced. When comparing tRF expression in urine EVs between BC patients with stage T1 disease and NCPs, 14 differentially expressed tRFs (DEtRFs) were identified. In serum supernatant, six DEtRFs were identified among stage T1 patients when comparing presurgery to postsurgery samples, and four DEtRFs were found when comparing presurgery samples to NCPs. By performing a blast search, we found that sequences of DEtRFs aligned with genomic sequences pertaining to processes relevant to cancer development, such as enhancers, regulatory elements and CpG islands. Our findings display a number of tRFs that may hold potential as biomarkers for the diagnosis and recurrence-free survival of BC.

Background: Alongside their long-term effects - post-concussion syndrome (PCS) - mild traumatic brain injuries (mTBI) are significant public health concerns. Currently, there is a lack of reliable biomarkers for diagnosing and monitoring mTBI and PCS. Exosomes are small extracellular vesicles secreted by cells that have recently emerged as a potential source of biomarkers for mTBI and PCS due to their ability to cross the blood-brain barrier and reflect the pathophysiology of brain injury. This study aimed to investigate the role of salivary exosomal biomarkers in mTBI and PCS. Methods: A systematic review using the PRISMA guidelines was conducted, and studies were selected based on their relevance to the topic. Results: Studies have shown that exosomal tau, phosphorylated tau (p-tau), amyloid beta (Aβ), and microRNAs (miRNAs) are potential biomarkers for mTBI and PCS. Specifically, elevated levels of exosomal tau and p-tau have been associated with mTBI and PCS, as well as with repetitive mTBI. Dysregulated exosomal miRNAs have also been observed in individuals with mTBI and PCS. Additionally, exosomal Prion cellular protein (PRPc), coagulation factor XIII (XIIIa), synaptogyrin-3, IL-6, and aquaporins have been identified as promising biomarkers for mTBI and PCS. Conclusion: Salivary exosomal biomarkers have the potential to serve as non-invasive and easily accessible diagnostic and prognostic tools for mTBI and PCS. Further studies are needed to validate these biomarkers and to develop standardized protocols for their use in clinical settings. Salivary exosomal biomarkers can improve the diagnosis, monitoring, and treatment of mTBI and PCS, leading to improved patient outcomes.

Amyotrophic lateral sclerosis (ALS) is a severe and incurable neurodegenerative disease, char-acterized by the progressive death of motor neurons, leading to paralysis and death. It is a rare disease distinguished by high patient-to-patient heterogeneity, making its study arduous and complex. Extracellular vesicles (EVs) emerged as an important player in ALS development. Thus, ALS phenotype-expressing cells can spread their abnormal bioactive cargos through the secretion of EVs, even at far distant tissues. Importantly, due to their nature and composition, EVs’ formation and cargo can be exploited for the better comprehension of this elusive disease and identification of novel biomarkers, as well as for potential therapeutic applications, such as those based on stem cell-derived exosomes. This review highlights the recent advances in the identification of the role of EVs in ALS etiopathology and how EVs can be promising new approaches for therapeutic strategies.

Viral infections induce exosomes containing viral material and inflammatory factors. During respiratory tract infection, exosomes can easily cross the blood-brain barrier and transmit the inflammatory signal to the brain; however, such a hypothesis has no experimental evidence. The study investigated whether exosomes from virus mimetic poly (I:C)-primed airway cells enter the brain and interact with brain immune cells microglia. Airway cells were isolated from Wistar rats and BALB/c mice; microglial cell cultures - from Wistar rats. Exosomes from poly (I:C)-stimulated airway cell culture medium were isolated by precipitation, visualised by transmission electron microscopy, and evaluated by nanoparticle analyser; exosomal markers CD81 and CD9 were determined by ELISA. For in vitro and in vivo tracking, exosomes were loaded with Alexa Fluor 555-labelled RNA. Intracellular reactive oxygen species (ROS) were evaluated by DCFDA fluo-rescence and mitochondrial superoxide - by MitoSOX. The exosomes from poly (I:C)-primed airway cells entered the brain within an hour after intranasal introduction, were internalised by microglia, and induced intracellular and intramitochondrial ROS production. There was no ROS increase in microglial cells was after treatment with exosomes from airway cells untreated with poly (I:C). The data indicate that virus-primed airway cell exosomes might enter the brain and induce the activation of microglial cells.

The proteomic profile of extracellular vesicles (EVs) has been of increasing interest, particularly in understanding cancer growth, drug resistance, and metastatic behavior. Emerging data suggests that cancer-derived EVs may carry an array of oncogenic cargo, including certain integrin proteins that may, in turn, promote cell detachment, migration, and selection of future metastatic sites. We previously reported a large comparison of secreted vesicle protein cargo across sixty diverse human cancer cell lines. Here, we analyze the distinct integrin profiles of these cancer EVs. We further demonstrate the enrichment of integrin receptors in breast cancer EVs compared to vesicles secreted from benign breast epithelial cells. Total EV integrin levels, including the quantity of integrins α2, αv, β4, and β5 correlate with breast tumor stage. In particular, integrin α2 also largely reflects progenitor cell expression, highlighting the utility of this integrin protein as a potential circulating biomarker of primary tumors. This study provides preliminary evidence of the value of vesicle-associated integrin proteins in cancer diagnosis and prediction of tumor stage. Differential expression of integrins across cancer cells, and selective packaging of integrins into EVs may contribute to further understanding the development and progression of tumor growth and metastasis across a variety of cancer types.

Exosomes, nanoscale extracellular vesicles, are a hot area of investigation in the biomedical field, as they have been shown to play a crucial role in the physiology of numerous tissues, including bone. This study explores the landscape of exosome-based bone regeneration research using infometric techniques. By relying on BERTopic, an advanced topic modeling algorithm, we analyzed a comprehensive corpus of scientific literature to identify key themes and trends in exosome research in the bone regeneration field. We then extracted significant concepts from the abstracts of the corpus and we used them to create knowledge graphs using GPT 3.5 turbo Large Language Model, to map the distribution of information within this domain. The resulting ide-oscape highlights the key ideas that aggregate most of the recent research in the area, from mesenchymal stem cell-derived exosomes to engineered exosome-integrated biomaterials. This exploration provides a holistic view of the field and uncovers its emerging trends, providing useful insight to guide future research directions.

Background: Alzheimer's Disease (AD) is a progressive neurodegenerative disorder with a rapidly increasing prevalence. Current therapeutic options primarily manage symptoms, not modifying the disease. Secretome-based therapies have emerged as a promising avenue for AD treatment in targeting multiple pathways and promoting neuroprotection and regeneration. This systematic review evaluated the preclinical and clinical evidences for secretome-based therapies in AD.Methods: A systematic search was conducted across Scopus, PubMed, ScienceDirect, and Cochrane Library. The SYRCLE risk of bias (RoB) tool was used for preclinical studies and Cochrane RoB 2.0 for clinical studies. We performed qualitative analysis of study results.Results: Included 21 in vivo studies and 2 clinical trials revealed promising outcomes of treatments involving secretomes, exosomes, and extracellular vesicles from different cell sources. The therapies could reduce amyloid plaque load, reactive gliosis, and enhance neuronal density. These findings suggested the treatments reveal mechanism of action in neuroprotection, neuroregeneration, and inflammation modulation, which are critical in AD pathology. Ongoing trials also supported the safety and efficacy of the treatment strategies. However, translational medical study faces several challenges regarding large-scale production, optimization of protocols, and understanding biomarkers. The heterogeneity in secretome-based therapies administration have complicated the comparison of study outcomes and the translation of preclinical findings into clinical settings. Deeper understanding of the secretome's mechanisms of action, optimal dosing, and delivery methods are needed to maximize therapeutic outcomes.Conclusion: Despite secretome-based therapies hold significant promise for AD treatment, addressing the identified gaps and limitations is crucial for advancing these therapies from preclinical research to clinical practice.

This study aimed to investigate the potential of Cord Blood Stem Cell-derived exosome vesicles (CBSC-EVs) in regulating cancer growth and preventing cellular damage. The study aimed to examine the effects of CBSC-EVs on CHL1 cancer cells and healthy fibroblasts. The study results reveal that CBSC-EVs have an anti-cancer/antioxidant effect on CHL1 cancer cells without inducing any toxic effects on healthy lymphocytes. Further analysis of CBSC-EVs revealed the presence of seven miRNAs (noncoding RNA molecules), including three from the Let 7 family, two from the Let 5 family, and two novel miRNAs. The function of the novel miRNAs was the main focus of the study. To assess the efficacy of CBSC-EVs, CHL1 cells (a type of malignant melanoma cell line) and human fibroblasts were grouped into different treatments. One group of those cell lines were treated with CBSC-EVs, and in the second group, the cells were transfected with either miRNA inhibitor Novel 1 (miRNA IN1) plus CBSC-EVs or miRNA inhibitor Novel 2 (miRNA IN2) and CBSC-EVs to knock down those novel miRNAs in the CBSC-EVs. Therefore, by comparing these groups, the function of novel miRNAs is more understandable. In this study, the Comet assay was employed to evaluate cancer cells' DNA damage and CCK8 to measure cell viability. The findings revealed that CBSC-EVs caused an increase in DNA damage in CHL1 cells compared to cells without treatment (p

Cancer-derived extracellular exosomes (EXs) promote tumor metastasis. This study investigates novel EXs influencing tumor aggressiveness and metastasis in gynecologic cancer. Data from ES2-derived EXs on aggressive ES2 cells and ascites-derived mesenchymal-type ovarian carcinoma stromal progenitor cells (MSC-OCSPCs) were analyzed using LC-MS/MS and integrated with TCGA survival analysis. Two novel EXs, UBE2NL and HIST2H3PS2, were identified in more aggressive ES2-derivatives and MSC-OCSPCs cells, but not in less aggressive SKOV3 cells. High UBE2NL and HIST2H3PS2 expression in EOC tissues was associated with advanced-stage carcinoma (p&lt;0.01) and shorter overall survival (p&lt;0.01). Besides, high HIST2H3PS2 expression in endometrial cancer (EC) tissues was also associated with shorter overall survival (p&lt;0.001) in all stages and advanced stages (p&lt;0.0001). In vitro, SKOV3 cells overexpressing UBE2NL or HIST2H3PS2 exhibited significantly greater invasion ability than controls (p&lt;0.001), further enhanced by their respective EXs (p&lt;0.001). In contrast, ES2 knockdown UBE2NL reduced invasion ability than ES2 cells (p&lt;0.001). In vivo, mice injected with ES2/shUBE2NL cells had a higher survival rate (p&lt;0.001) and fewer disseminated tumors (p&lt;0.05); in contrast, those injected with SKOV3/HIST2H3PS2 cells showed greater tumor dissemination (p&lt;0.01) and more severe ascites (p&lt;0.05) than controls. Tumor dissemination increased in mice receiving SKOV3/HIST2H3PS2 cells with EXs than those controls (p&lt;0.05). These findings suggest that UBE2NL and HIST2H3PS2 expression and EXs contribute to tumor aggressiveness and metastasis in gynecologic cancer.

Oral cancer (OC) presents a significant global health burden with rising incidence rates. Despite advancements in diagnosis and treatments, the survival rate for OC patients, particularly those with advanced or recurrent disease, remains low at approximately 20%. This poor prognosis is often due to a small population of cancer stem cells (CSCs) that are capable of self-renewal and immune evasion, thus playing pivotal roles in proliferation, tumor initiation, progression, metastasis, and therapy resistance. Exosomes, nano-sized extracellular vesicles (EVs), have emerged as crucial mediators of cell-to-cell communication within the tumor microenvironment (TME). These vesicles carry diverse molecules such as DNA, RNA, proteins, lipids, and metabolites, influencing various cellular processes. Emerging evidence suggests that CSC-derived EVs are significant in promoting tumor progression and metastasis and maintaining the balance between CSCs and non-CSCs, which is vital for intracellular communication within the TME of oral cancer. Recent reports indicate that oral cancer stem cell-derived EVs (OCSC-EVs) influence stemness, immune evasion, metastasis, angiogenesis, tumor reoccurrence, and drug resistance. Understanding OCSC-EVs could significantly improve oral cancer diagnosis, prognosis, and therapy. In this mini-review, we explore OCSC-derived exosomes in oral cancer, examining their potential as diagnostic and prognostic biomarkers that reflect CSC characteristics, and delve into their therapeutic implications, emphasizing their roles in tumor progression and therapy resistance. However, despite their promising potential, several challenges remain, including the need to standardize isolation and characterization methods and to elucidate exosome-mediated mechanisms. Thus, a comprehensive understanding of OCSC-EVs could pave the way for innovative therapeutic strategies that have the potential to improve clinical outcomes for OC patients.

Extracellular vesicles represent a large heterogeneous class of near and long-distance intercellular communication mediators, released by both prokaryotic and eukaryotic cells. Specifically, the scientific community has shown a growing interest in exosomes, which are nano-sized vesicles with an endosomal origin. Not so long ago, the physiological goal of exosome generation was largely unknown and required more investigation; at first, it was hypothesized that exosomes are able to remove excess, rejects and unnecessary constituents from cells to preserve cellular homeostasis. However, thanks to recent studies, the central role of exosomes in regulating cellular dialogue has emerged. Exosomes act as vectors on cell-cell signaling by their cargo, proteins, lipids, and nucleic acids, and influence physiological and pathological processes. The findings on exosomes are widespread in a large spectrum of biomedical applications from diagnosis and prognosis to thera-pies. In this review, we describe exosome biogenesis and the current methods for their isolation and characterization, emphasizing the role of their cargo in female reproductive processes, from gametogenesis to implantation, and the potential involvement in human female disorders.

Drug resistance in melanoma is a major hindrance in cancer therapy. Growth hormone (GH) plays a pivotal role in contributing to resistance to chemotherapy. Knocking down or blocking the GH receptor has been shown to sensitize the tumor cells to chemotherapy. Extensive studies have demonstrated that exosomes, a subset of extracellular vesicles, play an important role in drug resistance by transferring key factors to sensitize cancer cells to chemotherapy. In this study, we explore how GH modulates exosomal cargoes from melanoma cells and their role in drug resistance. We treated the melanoma cells with GH, doxorubicin, and GHR antagonist, pegvisomant, and analyzed the exosomes released. Additionally, we administered these exosomes to recipient cells. The GH-treated melanoma cells released exosomes with elevated levels of ABC transporters (ABCC1 and ABCB1), N-cadherin and MMP2, enhancing drug resistance and migration in recipient cells. GHR antagonism reduced these exosomal levels, restoring drug sensitivity and attenuating migration. Overall, our findings highlight a novel role of GH in modulating exosomal cargoes that drive chemoresistance and metastasis in melanoma. This understanding provides insights to the mechanisms of GH in melanoma chemoresistance and suggests GHR antagonism as a potential therapy to overcome chemoresistance in melanoma treatment.

Nucleic acid delivery through extracellular vesicles (EVs) is a well-preserved evolutionary mechanism in all life kingdoms including eukaryotes, prokaryotes, and plants. EVs naturally allow horizontal transfer of native as well as exogenous functional mRNA, that once incorporated in EVs is protected from enzymatic degradation. The possible use of EVs as carriers for vaccine has been investigated showing that EVs expressing recombinant SARS-CoV-2 S protein induced an immune response. Moreover, EV-based vaccines presenting the natural configuration of viral antigens have advantages in conferring long lasting immunization and lower toxicity than synthetic nanoparticles. To overcome the manufacturing limitations of EVs derived from eukaryotic cells, edible plant-derived EVs have been studied as an attractive alternative for vaccine delivery, especially for mucosal administration. We recently showed that EVs obtained from orange juice (oEVs) loaded with SARS-CoV-2 mRNAs protected their cargo from enzymatic degradation and were stable at room temperature for one year. Lyophilized oEVs containing the S1 mRNA were administered to rats by gavage and they induced a specific humoral immune response with generation of blocking antibodies, including IgA, that are the first mucosal barrier in the adaptive immune response. Moreover, a Th1 cytokine secretion occurred, suggesting a specific lymphocyte activation. In conclusion, mRNA-containing oEVs could be used for developing new oral vaccines due to optimal mucosal absorption, resistance to stress conditions, and the ability to stimulate a humoral and cellular immune response.

Exosomes are small subtypes of extracellular vesicles (EVs) naturally released by different types of cells into their environment. Their physiological roles appear to be multiple, and many aspects of their biological activities remain to be understood. These vesicles can transport and deliver a variety of cargoes, including proteins, metabolites, nucleic acids, and lipids. Consequently, it is argued that exosomes may serve as unconventional secretory vesicles, playing a crucial role as important vectors for intercellular communication and the maintenance of homeostasis. Exosome production and content can vary under several stresses or modifications in the cell microenvironment, influencing cellular responses both qualitatively and quantitatively. Thus, the analysis of EVs from multiple biofluids, due to its ease of implementation, has become a booming tool for monitoring various pathologies, particularly cancer, as we shall outline further on. During infectious processes, exosomes are described as double-edged swords, displaying both beneficial and detrimental effects. Indeed, during a viral infection, the production of EVs and circulating exosomes is often enhanced to signal danger, stimulate immunity, and possibly serve as pathological biomarkers. Conversely, viruses can disrupt or hijack the exosome content and production. In this review, we discuss the particular and ambiguous functions of exosomes in infectious contexts. Furthermore, we explore the vectoring capacity of exosomes in light of the extensive literature examining their function in mounting adaptive immune responses. Exosomes provide an interesting platform for antigen presentation and could therefore serve as novel therapeutic targets or be used in vaccine strategies.

Background: This review aims to explore the regulatory mechanism of microglial exosomes, particularly focusing on the role of miR-124-3p, in modulating neuroinflammation and promoting neuronal repair following traumatic brain injury (TBI). Methods: Multiple studies investigating the impact of microglial exosomal miRNAs, specifically miR-124-3p, on injured neurons and brain microvascular endothelial cells (BMVECs) in the context of TBI were reviewed. Results: Animal models of TBI, in vitro cell culture experiments, RNA sequencing analysis, and functional assays were employed to elucidate the mechanisms underlying the effects of miR-124-3p-loaded exosomes on neuroinflammation and neuronal repair. The increased expression of miR-124-3p in microglial exosomes after TBI inhibited neuronal inflammation and promoted neurite outgrowth. This effect was achieved by promoting the anti-inflammatory M2 polarization of microglia, suppressing mTOR signaling through downregulation of PDE4B, and inducing autophagy in BMVECs. These actions collectively contributed to neuroprotection, reduced blood-brain barrier leakage, and improved neurologic outcomes in animal models of TBI. Conclusion: Microglial exosomes, particularly those carrying miR-124-3p, have emerged as promising candidates for therapeutic interventions in TBI. These exosomes exhibit neuroprotective effects, attenuate neuroinflammation, and promote neuronal repair and plasticity. Targeting miR-124-3p and utilizing microglial exosomes as therapeutic agents hold great potential for future clinical translation in TBI management. However, further research is required to fully elucidate the underlying mechanisms and optimize their delivery strategies for effective treatment in human TBI cases.

Rapid progress in gene editing based on clustered regularly interspaced short palindromic repeats/CRISPR-associated protein (CRISPR/Cas) has revolutionized the study of gene and genome function and genetic disease correction. While numerous genetically modified cellular and animal models have been created to understand biological processes, the clinical application of CRISPR/Cas tools has been impeded by off-targeting and delivery problems. It is generally accepted that the delivery of CRISPR in the form of a ribonucleoprotein complex (RNP) substantially reduces the time of DNA exposure to the effector nuclease, minimizing off-target effects and facilitating clinical usage. This review focuses on CRISPR/Cas RNP delivery with retro/lentiviral particles and exosomes, whose parallel production by cells transfected with viral vectors is underestimated. We critically evaluate specific mechanisms of extracellular particle formation and loading with CRISPR/Cas for each system. Additionally, the details of Cas-nanoparticle entry and uncoating, previously unappreciated in the context of gene editing efficiency, are discussed. Based on existing knowledge about the consequences of intervention in retroviral assembly, entry, or exosome formation, we outline the potential problems with CRISPR/Cas delivery using extracellular nanoparticles and ways to address them.

Extracellular vesicles are considered a novel therapeutic tool, due to their ability to transfer their cargoes to target cells. Different strategies to directly load extracellular vesicles with RNA species have been proposed. Electroporation has been used for the loading of non-active vesicles, however the engineering of vesicles already carrying a therapeutically active cargo is still under investigation. We here set up a coincubation method to increase the anti-tumor effect of extracellular vesicles isolated from human liver stem cells (HLSC-EVs). Using the coincubation protocol, vesicles were loaded with the anti-tumor miRNA-145, and their effect was evaluated on renal cancer stem cell invasion. Loaded HLSC-EVs maintained their integrity and miR transfer ability, and miR-145 was protected by RNAse digestion possibly due to its binding to RNA-binding proteins on HLSC-EV surface, such as Annexin A2. Moreover, miR-145 coincubated HLSC-EVs were more effective in inhibiting the invasive properties of cancer stem cells, in comparison to naïve vesicles. The protocol reported here exploits a well-described property of extracellular vesicles to bind nucleic acids on their surface and protect them from degradation, in order to obtain an effective miRNA loading that results in the increase of the effect of naïve active extracellular vesicles.

The similarities between exosomes and liposomes, together with the high organotropism of several types of exosomes, have recently prompted the development of engineered-exosomes or exosome-mimetics, which may be artificial (liposomal) or cell-derived vesicles, as advanced platforms for targeted drug delivery. Here we provide the current state-of-the-art of using exosome or exosome-inspired systems for drug delivery. We review the various approaches investigated and the shortcomings of each approach. Finally the challenges identified up-to-date in this field are summarized.

Exosome-based therapy has emerged as a promising strategy for addressing diverse disorders, indicating the need for further exploration of the potential therapeutic effects of the exosome cargos. This study introduces "enhanced exosomes," a novel type of exosomes developed through a novel cell culture system. These specific exosomes may become potent therapeutic agents for treating ovarian disorders. In this study, we conducted a comparative analysis of the protein and miRNA cargo compositions of enhanced exosomes and naïve exosomes. Our findings revealed distinct cargo compositions in enhanced exosomes, featuring upregulated proteins such as EFEMP1, HTRA1, PAM, RSU1, and SDF4, suggesting their potential for treating ovarian disorders. MicroRNA profiling revealed that miR-1-3p, miR-103a-3p, miR-122-5p, miR-1271-5p, miR-133a-3p, miR-184, miR-203a-3p, and miR-206 are key players in regulating ovarian cancer and chemosensitivity by affecting cell cycle progression, cell proliferation, and cell development. We examined polycystic ovary syndrome and premature ovarian insufficiency and identified altered expression of various miRNAs, such as miR-106a-5p, miR-130b-5p, and miR-130b-3p, for diagnostic insights. This study highlights the potential of enhanced exosomes as new therapeutic agents for women's reproductive health, offering a detailed understanding of the impact of their cargo on ovarian disorders.

Urinary extracellular vesicles (uEV) hold non-invasive RNA biomarkers for genitourinary tract diseases. However, missing knowledge about reference genes and effects of pre-analytical choices hinder biomarker studies. We aimed to assess how pre-analytical variables (urine storage temperature, isolation workflow) affect diabetic kidney disease (DKD) -linked miRNAs or kidney -linked miRNAs and mRNAs (kidney-RNAs) in uEV isolates and to discover stable reference mRNAs across diverse uEV datasets. We studied nine raw and normalized sequencing datasets including healthy controls and individuals with prostate cancer or type 1 diabetes with or without albuminuria. We focused on kidney-RNAs reviewing literature for DKD-linked miRNAs from kidney tissue, cell culture and uEV/urine experiments. RNAs were analyzed by expression heatmaps, hierarchical clustering and selecting stable mRNAs with normalized counts (>200) and minimal coefficient of variation. Kidney-RNAs were decreased after urine storage at -20°C vs -80°C. Isolation workflows captured kidney-RNAs with different efficiencies. Ultracentrifugation captured DKD -linked miRNAs that separated healthy and diabetic macroalbuminuria groups. Eleven mRNAs were stably expressed across the datasets. Hence, preanalytical choices had variable effects on kidney-RNAs – analyzing kidney-RNAs complemented global correlation, which could fade differences in some relevant RNAs. Replicating prior DKD-marker results and discovery of candidate reference mRNAs encourages further uEV biomarker studies.

Abstract Metabolic syndrome (MetS) is considered a metabolic disorder that has been steadily increasing globally and seems to parallel the increasing prevalence of obesity. It consists of a cluster of risk factors, which traditionally includes obesity and hyperlipidemia, hyperinsulinemia, hypertension, and hyperglycemia. These four core risk factors are associated with insulin resistance (IR) and importantly, the MetS is known to increase the risk for developing cerebrocardiovascular disease and type 2 diabetes mellitus. The MetS had its early origins in IR and syndrome X. It has undergone numerous name changes with additional risk factors and variables being added over the years; however, it still remains the MetS worldwide for the past three decades. This overview continues to add novel insights to the MetS and suggests that leptin resistance with hyperleptinemia, aberrant mitochondrial stress and reactive oxygen species (ROS), impaired folate-mediated one-carbon metabolism with hyperhomocysteinemia, vascular stiffening, microalbuminuria, and visceral adipose tissues extracellular vesicle exosomes be added to the list of associated variables. Notably, the role of a dysfunctional and activated endothelium and deficient nitric oxide bioavailability along with a dysfunctional and attenuated endothelial glycocalyx, vascular inflammation, systemic metainflammation, and the important role ROS and reactive species interactome are discussed. With new insights and knowledge regarding the MetS, comes the possibility of new findings through further research.

Background/Aims: Obstructive sleep apnea syndrome (OSAS) affects a large part of the aging population. It is characterized by chronic intermittent hypoxia and associated with neurocognitive dysfunction. One hypothesis is that the blood-brain barrier (BBB) functions could be altered by exosomes. Exosomes are nanovesicles found in biological fluids. Through the study of exosomes and their content in tau and amyloid beta (Ab), the aim of this study was to show how exosomes could be used as biomarkers of OSAS and of their cognitive disorders. Methods: Two groups of 15 volunteers from the PROOF cohort were selected: severe apnea (AHI >30) and control (AHI <5). After exosome isolation from blood serum, we characterized and quantified them (CD81, CD9, CD63) by western blot and ELISAs and put them 5h in contact with an in vitro BBB model. The apparent permeability of the BBB was measured using sodium-fluorescein and TEER. Cell ELISAs were performed on tight junctions (ZO-1, claudin-5, occludin). The amount of tau and Ab proteins found in the exosomes was quantified using ELISAs. Results: Compared to controls, OSAS patients had a greater quantity of exosomes, tau and Ab proteins in their blood sera, which induced an increase in BBB permeability in the model and was reflected by a loss of tight junction’expression. Conclusion: Elderly patients suffering severe OSAS released more exosomes in serum from the brain compartment than controls. Such exosomes increased BBB permeability. The impact of such alterations on risk of developing cognitive dysfunction and/or neurodegenerative diseases is questioned.

Merkel cell carcinoma (MCC) is a rare, highly aggressive skin cancer characterized by two etiologies: the first one, observed in most cases, is attributed to Merkel cell polyomavirus (MCPyV), a DNA tumor virus, while the second one is due to ultraviolet (UV) radiation exposure. Currently, there are limited diagnostic, prognostic, and therapeutic biomarkers available for MCC. MicroRNAs (miRNAs) are small RNA molecules that do not code for proteins but regulate various cellular processes, including cell cycle progression, proliferation, differentiation, and apoptosis. The dysregulation of miRNAs has been associated with a wide range of cancers since they can act as either tumor suppressors or oncogenes. This paper aims to collect, summarize and re-organize the recent discoveries concerning miRNAs, whose dysregulation in the pathogenesis and progression of MCC is slowly emerging. Furthermore, the potential clinical applications of miRNAs as diagnostic biomarkers, possible differentiation between MCPyV-related and unrelated MCC, predictors of response to therapy and prognostics are also discussed. From this review, it emerges that miRNAs may have, in the near future, the potential to become clinically significant in improving the diagnostic accuracy, prognostic evaluation, and therapeutic options of MCCs. Finally, the new perspectives on the poorly explored field of artificial intelligence in MCC are provided.

Extracellular vesicles (EVs), a diverse group of cell-derived exocytosed particles, are pivotal in mediating intercellular communication due to their ability to selectively transfer biomolecules to specific cell types. EVs, composed of proteins, nucleic acids, and lipids, are taken up by cells to affect a variety of signaling cascades. Research in the field has primarily focused on stem-cell derived EVs, with a particular focus on mesenchymal stem cells, for their potential therapeutic benefits. Recently, tissue specific EVs or cell type specific extracellular vesicles (CTS-EVs), have garnered attention for their unique biogenesis and molecular composition because they enable highly targeted cell-specific communication. Various studies have outlined the roles that CTS-EVs play in signaling for physiological function and maintenance of homeostasis, including immune modulation, tissue regeneration, and organ development. These properties are also exploited for disease propagation, such as in cancer, neurological disorders, infectious diseases, autoimmune conditions, and more. The insights gained from analyzing CTS-EVs in different biological roles not only enhance our understanding of intercellular signaling and disease pathogenesis, but also open new avenues for innovative diagnostic biomarkers and therapeutic targets for a wide spectrum of medical conditions. This review comprehensively outlines current understanding of CTS-EV origins, function within normal physiology, and implications in diseased states.

Each year, millions of individuals suffer from a non-healing wound, abnormal scarring, or injuries accompanied by an infection. For these cases, scientists are searching for new therapeutic interventions, from which one of the most promising is the use of extracellular vesicles (EVs). Naturally, EV-based signalling takes part in all four wound healing phases: hemostasis, inflammation, proliferation and remodelling. Such an extensive involvement of EVs suggests exploiting their action to modulate the impaired healing phase. Furthermore, next to their natural wound healing capacity, EVs can be engineered for better defined pharmaceutical purposes, such as carrying specific cargo or targeting specific destinations by labelling them with certain surface proteins. This review aims to promote scientific awareness in basic and translational research of EVs by summarizing the current knowledge about their natural role in each stage of skin repair and the most recent findings in application areas, such as wound healing, skin regeneration and treatment of dermal diseases, including the stem cell-derived, plant-derived and engineered EVs.

Extracellular vesicles (EVs) are membranous vesicles secreted by both prokaryotic and eukaryotic cells and play a vital role in intercellular communication. EVs are classified into several subtypes based on their origin, physical characteristics, and biomolecular makeup. Exosomes, a subtype of EVs, are released by the fusion of multivesicular bodies (MVB) with the plasma membrane of the cell. Several methods have been described in literature to isolate exosomes from biofluids including blood, urine, milk, and cell culture media among others. While differential ultracentrifugation (dUC), has been widely used to isolate exosomes, other techniques including ultrafiltration, precipitating agents such as poly-ethylene glycol (PEG), immunoaffinity capture, microfluidics and size exclusion chromatography (SEC) have emerged as credible alternatives with pros and cons associated with each. In this review, we provide a summary of commonly used exosomal isolation techniques with a focus on SEC as an ideal methodology. We evaluate the efficacy of SEC to isolate exosomes from an array of biological fluids, with a particular focus on its application to adipose tissue-derived exosomes. We argue that exosomes isolated via SEC are relatively pure and functional, and that this methodology is reproducible, scalable, inexpensive, and does not require specialized equipment or user expertise.

Background: Extracellular Vesicles are pivotal mediators in intercellular communication, facilitating the exchange of biological information among healthy, pathological and tumor cells. Between the diverse subtypes of extracellular vesicles, exosomes have unique properties, clinical and therapeutical applications, even towards cancer. Breast cancer ranks as one of the most prevalent malignancies across the globe. Both the tumor core and its surrounding microenvironment engage in a complex, orchestrated interaction that facilitates the cancer’s growth and spread. Methods: The most valuable and significant PubMed Literature about extracellular vesicles and adipose–derived stem cells exosomes was selected and analyzed in order to report their biological properties and potential applications, in particular on the Triple–Negative Breast Cancer. Results: Adipose–derived stem cells exosomes represent a potential tool to target the tumor core of the Triple–Negative Breast Cancer, its microenvironment and surrounding tissues including metastasis. The authors are developing a supportive Triple–Adipose–derived stem cells Exosomes [T.A.E.] Technology against breast cancer in order to perform a selective preconditioning of the cancer before or while the traditional oncological treatments are running. Conclusion: The possibility to exploit the impact of Adipose–derived stem cells exosomes within the T.A.E. Technology against the Triple–Negative breast cancer is real, highlighting a new era for supportive measures against breast cancer.Keywords: Extracellular vesicles; Exosomes; Adipose–derived stem cells, Tumor microenvironment, Triple–Negative Breast Cancer, T.A.E. Technology.

Because of their high biocompatibility, stability, ability to negotiate biological barrier passage, and functionalization properties, biological nanoparticles have been actively investigated for many medical applications. Biological nanoparticles, including natural extracellular vesicles (EVs) and synthetic extracellular vesicle-mimetic nanovesicles (EMNVs) represent novel drug delivery vehicles that can accommodate different payloads. In this study, we investigated EVs and EMNVs for their physical, biological and delivery properties and we showed that EMNVs have similar delivery properties compared to EVs. In addition, these nanotherapeutics were analyzed for their cytostatic properties in combination with the FDA-approved drug hydroxychloroquine (HCQ), which increased their cytostatic thanks to its lysosome-destabilizing properties. Altogether, these data demonstrated that, at least in vitro, the use of synthetic biomimetic particles is comparable to the natural counterparts, while their synthesis is significantly faster and more cost effective. In addition, we highlighted the benefits of combining biological nanoparticles with a lysosome destabilizing agent that increased the delivery properties of the particles.

Extracellular vesicles (EV), including exosomes and microvesicles, are released from various cells and alter recipient cell phenotypes and fates by their biomolecules. Here we review current knowledge about tumor EVs and how they prompt malignant cell communication with tumor-associated cells, such as cancer-associated fibroblasts, tumor endothelial cells, and immune cells. We delineate the major pathways and molecular players that influence each step of cancer initiation, progression, and resistance. Of note, cancer exosomes involve immunosuppression by tumor-associated macrophages, myeloid-derived suppressor cells, and regulatory T cells. Moreover, tumor exosomes can induce the apoptosis of killer T cells and immune checkpoint of dendritic cells and attenuate natural killer cells. An in-depth understanding of EV biology is essential to ensure the clinical development of exosome/EV-based therapeutic products, which will be of benefit to exosome manipulation in cancer management.

Tumorigenesis is a complex and dynamic process involving cell-cell and cell-extracellular matrix (ECM) interactions that allow tumor cell growth, drug resistance and metastasis. This review provides an updated summary of the role played by the tumor microenvironment (TME) components and hypoxia in tumorigenesis and highlight various ways through which tumor cells reprogram normal cells including into phenotypes that are pro-tumorigenic including cancer associated- fibroblasts, -macrophages and -endothelial cells. Tumor cells secrete numerous factors leading to transformation of a previously anti-tumorigenic environment into a pro-tumorigenic environment. Once formed, solid tumors continue to interact with various stromal cells including local and infiltrating fibroblasts, macrophages, mesenchymal stem cells, endothelial cells, pericytes, and secreted factors and the ECM within the tumor microenvironment (TME). The TME is key to tumorigenesis, drug response and treatment outcome. Importantly, stromal cells and secreted factors can initially be anti-tumorigenic but over time promote tumorigenesis and induce therapy resistance. To counter hypoxia, increased angiogenesis leads to formation of new vascular networks in order to actively promote and sustain tumor growth via supply of oxygen and nutrients whilst removing metabolic waste. Angiogenic vascular network formation aid in tumor cell metastatic dissemination. Successful tumor treatment and novel drug development require the identification and therapeutic targeting of pro-tumorigenic components of the TME including cancer-associated- fibroblasts (CAFs) and -macrophages (CAMs), hypoxia, blocking ECM-receptor interactions, in addition to targeting of tumor cells. Re-programming of stromal cells and the immune response to be anti-tumorigenic is key to therapeutic success. Lastly, this review highlights potential TME- and hypoxia-centred therapies under investigations.

Extracellular vesicles (EV) such as exosomes, are newly recognized fundamental, natural and physiologic particles of life that seemingly are involved all biologic processes and clinical diseases. Due to their universal involvements, understanding the nature and the potential therapeutic uses of these nano-vesicles requires innovative experimental approaches, in virtually every field. Of the EV group, exosome nano-vesicles and larger companion extracellular micro vesicles (MV) can mediate completely new phenomena dependent on intercellular transfer of proteins and selected RNAs; particularly miRNAs, between donor and targeted cells to elicit epigenetic alterations inducing functional cellular changes. These recipient acceptor cells are nearby (paracrine transfers) or far away after distribution via the circulation (endocrine transfers). The major properties of such vesicles seem to have been conserved over eons, suggesting that they may have ancient evolutionary origins arising perhaps even before cells in the primordial soup from which life evolved. Their potential ancient evolutionary attributes may be responsible for the ability of some modern day exosomes to withstand unusually harsh conditions; perhaps due to unusual membrane lipid compositions. This is exemplified by maternal milk exosome survival of the neonatal acid/enzyme rich stomach. It is postulated that this also applies to their durable presence in phagolysosomes; suggesting unique intracellular release of contents. A major issue discussed is the generally poorly realized superiority of these naturally evolved nano vesicles to therapies compared human engineered artificial nanoparticles; say for treatment of cancers.

Exosomes, natural nanovesicles that contain a cargo of biologically active molecules such as lipids, proteins, and nucleic acids, are released from cells to the extracellular environment. They then act as autocrine, paracrine, or endocrine mediators of communication between cells by delivering their cargo into recipient cells and causing downstream effects. Exosomes are greatly enriched in miRNAs, which are small non-coding RNAs that act as cytoplasmic posttranscriptional repression agents, modulating the translation of mRNAs into proteins, as well as nuclear transcriptional gene activators. Neuronal exosomal miRNAs have important physiologic functions in the Central Nervous System (CNS), including cell-to-cell communication, synaptic plasticity, and neurogenesis, as well as modulating stress and inflammatory responses. Stress-induced changes of exosomal functions include effects on neurogenesis and neuroinflammation, which can lead to the appearance of various neuropsychiatric disorders, such as schizophrenia, major depression, bipolar disorder, and Alzheimer's and Huntington’s's diseases. The current knowledge regarding the roles of exosomes in the pathophysiology of common mental disorders is discussed in this review.

Lipofilling is an option for breast reconstruction after tumor resection to avoid the complications of an implant-based reconstruction. Although some concerns exist regarding the oncological safety of a tissue rich in mesenchymal stem cells with their proangiogenic and proliferation-supportive properties, there are also reports that adipose tissue-derived stem cells can exhibit antitumoral properties. We isolated primary adipose tissue-derived stem cells. Both conditioned medium and exosomes were harvested from the cell culture and used to treat the breast cancer cell line MCF-7. Cell viability, cytotoxicity, and gene expression of MCF-7 cells in response to the indirect co-culture were evaluated. MCF-7 cells incubated with exosomes from adipose tissue-derived stem cells show reduced cell viability in comparison to MCF-7 cells incubated with adipose-tissue derived stem cell-conditioned medium. Expression of proapoptotic genes was upregulated, expression of antiapoptotic genes was downregulated. The debate about the oncological safety of autologous fat grafting after tumor resection continues. Here, we show that exosomes from adipose tissue-derived stem cells exhibit some antitumoral properties on breast cancer cell line MCF-7.

Extracellular vesicles (EV) are a very heterogeneous group of cell-derived vesicles released by almost all kind of living cells. EV are involved in intercellular communication, both locally and systemically, since they induce signals and transfer their contents (proteins, lipids, RNAs) to other cells, which subsequently trigger a wide variety of biological responses in the target cells. How-ever, cell surface receptor-induced EV release is limited to cells from the immune system, includ-ing T lymphocytes. T cell receptor activation of T lymphocytes induces secretion of EV containing T cell receptor for antigen and several bioactive molecules, including proapoptotic proteins. These EV are thus specific for antigen-bearing cells, which make them ideal candidates for a cell-free, EV-dependent cancer therapy. In this review we discuss the generation of EV by T lymphocytes and some potential therapeutic approaches of these EV.

Background: Tumor microenvironment (TME) plays a crucial role in virtually every aspect of tumorigenesis of glioblastoma multiforme (GBM). The dysfunctional TME promotes drug resistance, disease recurrence and distant metastasis. Recent evidence indicates that exosomes released by stromal cells within TME may promote oncogenic phenotypes via transferring signaling molecules such as cytokines, proteins and microRNAs. Results: In this study, clinical GBM samples were collected and analyzed. We found that GBM-associated macrophages (GAMs) secreted exosomes which were enriched with oncomiR-21. Co-culture of GAMs (and GAM derived exosomes) and GBM cell lines resulted in the increased GBM cells’ resistance against temozolomide (TMZ) by upregulating pro-survival gene, PDCD4 and stemness markers Sox2, STAT3, Nestin and miR-21-5p and increased M2 cytokines, IL-6 and TGF-β1 secreted by GBM cells, promoting the M2 polarization of GAMs. Subsequently, pacritinib treatment suppressed GBM tumorigenesis and stemness; more importantly, pacritinib-treated GBM cells showed markedly reduced ability to secret M2 cytokines and reduced miR-21 enriched exosomes secreted by GAMs. Pacritinib-mediated effects were accompanied by a reduction of oncomiR miR-21-5p, by which tumor suppressor PDCD4 was targeted. We subsequently established a patient-derived xenograft models where mice bore patient GBM and GAMs. The treatment of pacritinib, and the combination of pacritinib/TMZ appeared to significantly reduce tumorigenesis of GBM/GAM PDX mice, overcome TMZ-resistance, and M2 polarization of GAMs. Conclusion: In summation, we showed that potential of pacritinib alone or in combination with TMZ for suppressing GBM tumorigenesis via modulating STAT3/miR-21/PDCD4 signaling. Further investigations are warranted for adopting pacritinib for the treatment of TMZ-resistant GBM in the clinical settings.

Neural tissue engineering, nanotechnology and neuroregeneration are diverse biomedical disciplines that have been working together in recent decades to solve the complex problems linked to central nervous system (CNS) repair. It is known that the CNS demonstrates a very limited regenerative capacity because of a microenvironment that impedes effective regenerative processes, making development of CNS therapeutics challenging. Given the high prevalence of CNS conditions such as stroke that damage the brain and place a severe burden on afflicted individuals and on society, it is of utmost significance to explore the optimum methodologies for finding treatments that could be applied to humans for restoration of function to pre-injury levels. Extracellular vesicles (EVs), also known as exosomes, when derived from mesenchymal stem cells, are one of the most promising approaches that have been attempted thus far, as EVs deliver factors that stimulate recovery by acting at the nanoscale level on intercellular communication while avoiding the risks linked to stem cell transplantation. At the same time, advances in tissue engineering and regenerative medicine have offered the potential of using hydrogels as bio-scaffolds in order to provide the stroma required for neural repair to occur, as well as the release of biomolecules facilitating or inducing the reparative processes. This review introduces a novel experimental hypothesis regarding the benefits that could be offered if EVs were to be combined with biocompatible injectable hydrogels. The rationale behind this hypothesis is presented, analyzing how a hydrogel might prolong the retention of EVs and maximize the localized benefit to the brain. This sustained delivery of EVs would be coupled with essential guidance cues and structural support from the hydrogel until neural tissue remodeling and regeneration occur. Finally, the importance of including non-human primate (NHP) models in the clinical translation pipeline, as well as the added benefit of multi-modal neuroimage analysis to establish non-invasive, in vivo, quantifiable imaging-based biomarkers for CNS repair are discussed, aiming for more effective and safe clinical translation of such regenerative therapies to humans.

Standard Non-Melanoma Skin Cancer (NMSC) treatment involves surgery, recently combined with chemotherapy or immunotherapy in case of advanced tumors. Exosomes, integral to carcinogenesis, are found in NMSC, releasing mediators impacting tumor progression. Nevertheless, the precise intercellular signaling role of NMSC-derived exosomes remains unclear. This review aims to elucidate their potential role in NMSC diagnosis and treatment. A systematic review encompassed literature searches in electronic databases from inception to September 2023, based on certain inclusion and exclusion criteria, addressing NMSC-derived exosomes, their molecular cargo and their implications in the diagnosis, prognosis, and treatment of NMSC. Key components were identified. Extracellular vesicle (EV) proteins and RNA emerged as diagnostic biomarkers in EV-based liquid biopsy. Circular RNA CYP24A1, known for its molecular stability, holds promise as a diagnostic biomarker. Long noncoding RNAs (lincRNA-PICSAR) and Desmoglein 2 (DSg2) are linked to drug resistance, serving as prognostic biomarkers. EV mediators are actively investigated for their potential role as drug delivery agents. In conclusion, this systematic review showed that NMSC-derived EVs display promise as therapeutic targets and diagnostic biomarkers. Further research is imperative to fully comprehend exosome mechanisms and explore their potential in cancer diagnosis and treatment.

Extracellular vesicles (EVs) are cell-derived membranous particles secreted by all cell types into the extracellular milieu. EVs carry, protect, and transport a wide array of bioactive cargoes to recipient/target cells. EVs regulate physiological and pathophysiological processes in recipient cells and are important in therapeutics/drug delivery. Despite these great attributes of EVs, an efficient protocol for EV separation from biofluids is lacking. Numerous techniques have been adapted for the separation of EVs with size exclusion chromatography (SEC)-based methods being the most promising. Here, we review the SEC protocols used for EV separation, and discuss opportunities for significant improvements, such as the development of novel particle purification liquid chromatography (PPLC) system capable of tandem purification and characterization of biological and synthetic particles with near-single vesicle resolution. Finally, we identify future perspectives and current issues to make PPLC a tool capable of providing a unified, automated, adaptable, yet simple and affordable particle separation resource.

In contrast to normal cells, tumor cells of multiple entities overexpress the Heat Shock Protein 70 (Hsp70) not only in the cytosol, but also present it on their plasma membrane in a tumor-specific manner. Furthermore, membrane-Hsp70 positive tumor cells actively release Hsp70 into lipid microvesicles termed exosomes into the blood. Due to conformational changes of Hsp70 in the lipid environment, most commercially available antibodies fail to detect membrane-bound and exosomal Hsp70. To fill this gap and to assess the role of exosomal Hsp70 in the circulation as a potential tumor biomarker, we established the novel complete Hsp70 (compHsp70) sandwich ELISA using two monoclonal antibodies (mAbs) that are able to recognize both, free and lipid-associated Hsp70 on the cell surface of viable tumor cells and exosomes. The epitopes of the mAbs cmHsp70.1 (aa 451-461) and cmHsp70.2 (aa 614-623) that are conserved among different species reside in the substrate-binding domain of Hsp70, with measured affinities of 0.42 nM and 0.44 nM, respectively. Validation of the compHsp70 ELISA revealed a high intra- and inter-assay precision, linearity in a concentration range of 1.56 to 25 ng/ml, high recovery rates of ‘spiked’ liposomal Hsp70 (>84%), comparable values between human serum and plasma samples, and no interference by food intake or age of the donors. Hsp70 concentrations in the circulation of patients with glioblastoma, squamous cell or adeno non-small cell lung carcinoma (NSCLC) at diagnosis were significantly higher than those of healthy volunteers. Hsp70 concentrations dropped concomitantly with the decrease in viable tumor mass on irradiation of patients with approximately 20 Gy (range 18 – 22.5 Gy) or after completion of radiotherapy (60 - 70 Gy). In summary, the compHsp70 ELISA presented herein provides a highly sensitive and reliable tool for measuring free and exosomal Hsp70 in liquid biopsies of tumor patients, levels of which can be used as a predictive tumor-specific biomarker, risk assessment and for monitoring therapeutic outcome.

Abstract Tetraspanin CD63 is a cluster of cell surface proteins with four transmembrane domains which associates with tetraspanin-enriched microdomains and typically localizes to late endosomes and lysosomes. CD63 plays an important role in cellular trafficking of different proteins, EV cargo sorting and vesicles formation. We have preciously shown that CD63 is important in LMP1 trafficking to EVs and this also affects LMP1 mediated intracellular signaling including MAPK/ERK, NF-κB and mTOR activation. Using the BioID combined with mass spectrometry, we sought to define the broad CD63 interactome and how LMP1 modulates this network of interacting proteins. We identified a total of 1600 total proteins as proximal interacting newtwork of proteins to CD63. Biological process enrichment analysis revealed significant involvement in signal transduction, cell communication, protein metabolism and transportation. The CD63 only interactome was enriched in Rab GTPases, SNARE proteins and sorting nexins while adding LMP1 into the interactome increased presence of signaling and ribosomal proteins. Our results showed that LMP1 alters the CD63 interactome, shifting the network of proteins enrichment from protein localization and vesicle mediated transportation to metabolic processes and translation. We also show that LMP1 interacts with mTor, Nedd4L and PP2A indicating formation of a multiprotein complex with CD63 thereby potentially regulating LMP1 dependent mTor signaling. Collectively, the comprehensive analysis of CD63 proximal interacting proteins provides insights into network of partners required for endocytic trafficking, extracellular vesicle cargo sorting, formation and secretion.

Neutrophils are the most abundant immune cells and make up about 70% of white blood cells in human blood and play a critical role as the first line of defense in the innate immune response. They also help regulate the inflammatory environment to promote tissue repair. However, in cancer, neutrophils can be manipulated by tumors to either promote or hinder tumor growth depending on the cytokine pool. Studies have shown that tumor-bearing mice have increased levels of neutrophils in peripheral circulation, and that neutrophil-derived exosomes can deliver various cargos, including lncRNA and miRNA, which contribute to tumor growth and degradation of extracellular matrix. Exosomes derived from immune cells generally possess anti-tumor activities and induce tumor-cell apoptosis by delivering cytotoxic proteins, ROS generation, H2O2 or activation of Fas-mediated apoptosis in target cells. Engineered exosome-like nanovesicles have been developed to deliver chemotherapeutic drugs precisely to tumor cells. However, tumor-derived exosomes can aggravate cancer-associated thrombosis through the formation of neutrophil extracellular traps. Despite the advancements in neutrophil-related research, a detailed understanding of tumor-neutrophil crosstalk is still lacking and remains a major barrier in developing neutrophil-based or targeted therapy. This review will focus on the communication pathways between tumors and neutrophils, and the role of neutrophil-derived exosomes (NDEs) in tumor growth. Additionally, potential strategies to manipulate NDEs for therapeutic purposes will be discussed.

Extracellular vesicles (EVs) have been identified as novel mediators of intercellular communication. They work via delivering the sequestered cargo to cells in close vicinity as well as distant sites in the body, regulating pathophysiological processes. Cell death and inflammation are biologically crucial processes in both normal physiology and pathology. These processes are indistinguishably linked with their effectors modulating the other process. For instance, during an unresolvable infection, the upregulation of specific immune mediators leads to inflammation causing cell death and tissue damage. EVs have gained considerable interest as mediators of both cell death and inflammation during conditions such as sepsis. This review summarizes the types of extracellular vesicles known to date and their roles in mediating immune responses leading to cell death and inflammation with specific focus on sepsis and lung inflammation.

(1) Background: Alcohol abuse has a high impact on the mortality and morbidity related to a great number of diseases and is responsible for the development of alcoholic liver disease (ALD). It remains challenging to detect and evaluate its severity, which is crucial for prognosis. In this work, we studied if urinary EVs (uEVs) could serve in diagnose and evaluate cirrhosis in ALD. (2) Methods: uEVs characterization by cryo-electron microscopy (Cryo-EM), Nanoparticle Tracking Analysis (NTA) and Western blotting (WB) was performed in a cohort of 21 controls and 21 cirrhotic patients. Then, proteomics of urinary EVs (uEVs) was carried out in a second cohort of 6 controls and 8 patients in order to identify new putative biomarkers for cirrhosis in ALD. (3) Results: uEVs concentration, size and composition were altered in cirrhotic patients. A total of 1304 proteins were identified in uEVs, and 90 of them were found to be altered in cirrhotic patients. (4) Conclusions: uEVs could be considered as a tool and a supplier of new biomarkers for ALD, whose application would be especially relevant in chronic patients. Yet, further research is necessary to obtain more relevant result in clinical terms.

Biological nanoparticles (NPs), such as extracellular vesicles (EVs), exosome-mimetic nanovesicles (EMNVs) and nanoghosts (NGs), are perspective non-viral delivery vehicles for all types of therapeutic cargo. Biological NPs are renowned for their exceptional biocompatibility and safety, alongside their ease of functionalization, but a significant challenge arises when attempting to load therapeutic payloads, such as nucleic acids (NAs). One effective strategy involves fusing biological NPs with liposomes loaded with NAs, resulting in hybrid carriers that offer the benefits of both biological NPs and the capacity for high cargo loads. Despite their unique parameters, one of the major issues of virtually any nanoformulation is the ability to escape degradation in the compartment of endosomes and lysosomes which determines the overall efficiency of nanotherapeutics. In this study, we fabricated all major types of biological and hybrid NPs and studied their response to acidic environment observed in endolysosomal compartment. In this study, we show that EMNVs display increased protonation and swelling relative to EVs and NGs in an acidic environment. Furthermore, the hybrid NPs exhibit an even greater response compared to EMNVs. Short-term incubation of EMNVs in acidic pH corresponding to late endosomes and lysosomes again induces protonation and swelling, whereas hybrid NPs are ruptured, resulting in the decline of their quantities. Our findings demonstrate that in an acidic environment, there is enhanced rupture and release of vesicular cargo observed in hybrid EMNVs that are fused with liposomes compared to EMNVs alone. This was confirmed through PAGE electrophoresis analysis of mCherry protein loaded into nanoparticles. In vitro analysis of NPs colocalization with lysosomes in HepG2 cells demonstrated that EMNVs mostly avoid endolysosomal compartment whereas hybrid NPs escape it over time. To conclude, (1) hybrid biological NPs fused with liposomes appear more efficient in the endolysosomal escape via the mechanism of proton sponge associated with scavenging of protons by NPs, influx of counterions and water, and rupture of endo/lysosomes, but (2) EMNVs are much more efficient than hybrid NPs in actually avoiding endolysosomal compartment in human cells. These results reveal biochemical differences across four major types of biological and hybrid NPs, and indicate that EMNVs are more efficient in escaping or avoiding endolysosomal compartment.

The onset and progression of human inflammatory joint diseases are strongly controlled by the activation of resident synovium/infrapatellar fat pad (IFP) pro-inflammatory and pain-transmitting signaling. We recently reported that intra-articularly injected IFP-derived Mesenchymal Stem/Stromal Cells (IFP-MSC) acquire a potent immunomodulatory phenotype and actively degrade Substance P (SP) via neutral endopeptidase CD10 (neprilysin). Our hypothesis is that IFP-MSC robust immunomodulatory therapeutic ef-fects are largely exerted via their CD10-bound exosomal secretome (IFP-MSC EXOs) by attenuating synoviocyte pro-inflammatory activation and articular cartilage degradation. Herein, IFP-MSC EXOs were isolated from CD10High- and CD10Low-expressing IFP-MSC cultures and their exosomal miRNA cargo was assessed using multiplex methods. Functionally, we interrogated the effect of CD10High and CD10Low EXOs on stimulated by inflammatory/fibrotic cues synoviocytes monocultures and cocultures with IFP-MSC de-rived chondropellets. Finally, CD10High EXOs were tested in vivo for their therapeutic capacity in an animal model of acute synovitis/fat pad fibrosis. Our results showed that CD10High and CD10Low EXOs possess distinct miRNA profiles. Reactome analysis of miRNAs highly present in exosomes showed their involvement in the regulation of six gene groups, particularly the immune system. Stimulated synoviocytes exposed to IFP-MSC EXOs demonstrated significantly reduced proliferation and altered inflammation-related molecular profiles compared to control stimulated synoviocytes. Importantly, CD10High EXOs treatment of stimulated chondropellets/synoviocytes cocultures indicated a significant chondroprotective effects. Therapeutically, CD10High EXOs treatment resulted in robust chondroprotective effects by retaining articular cartilage structure/composition and PRG4 (lubricin)-expressing cartilage cells in the animal model of acute synovitis/IFP fibrosis. Our study suggests that CD10High EXOs possess immuno-modulatory miRNA attributes with strong chondroprotective/anabolic effects for articular cartilage in vivo. The results could serve as a foundation for EXOs-based therapeutics for the resolution of detrimental aspects of immune-mediated inflammatory joint changes associated with conditions such as osteoarthritis (OA).

Inflammatory diseases are common pathological processes caused by various acute and chronic factors and some of them are autoimmune diseases. Exosomes are fundamental extracellular vesicles secreted by almost all cells, which contain a series of constituents, i.e. cytoskeletal and cytosolic proteins (actin, tubulin, histones), nucleic acids (mRNA, miRNA, DNA), lipids (diacylglycerophosphates, cholesterol, sphingomyelin, ceramide), and other bioactive components (cytokines, signal transduction proteins, enzymes, antigen presentation and membrane transport/fusion molecules, adhesion molecules). This review would be a synopsis of the actual knowledge on the contribution of exosomes from different cell sources as possible therapeutic agents against inflammation, focusing on several inflammatory diseases, neurological diseases, rheumatoid arthritis and osteoarthritis, intestinal bowel disease, asthma, liver and kidney injuries. Current knowledge indicates that the role of exosomes in therapy of inflammation and in inflammatory diseases could be distinctive. Main limitations to their clinical translation are still production, isolation, and storage. Additionally, there is an urgent need to personalize the treatments in terms of selection of exosomes, their dosages and routes of administration, and a deeper knowledge about their biodistribution, type and incidence of adverse events and long-term effects of exosomes. In conclusion, exosomes can very promising next generation therapeutic option, superior to synthetic nanocarriers and cell therapy, and can represent a new strategy of effective, safe, versatile and selective delivery systems in the future.

Extracellular vesicles (EVs) are involved in intercellular communication during carcinogenesis and cancer cells are able to secrete EVs, in particular exosomes containing molecules, that can be transferred to recipient cells to induce pathological processes and significant modifications, as metastasis, increase of proliferation and carcinogenesis evolution. FZD proteins, a family of receptors comprised in the Wnt signaling pathway, play an important role in carcinogenesis of gastroenteric tract. Here, a still unrecognized role of Frizzled 10 (FZD10) protein was identified. In particular, the presence of FZD10 and FZD10-mRNA in exosomes extracted from culture medium of the untreated colorectal, gastric, hepatic and cholangio cancer cell lines, was detected. A substantial reduction in the FZD10 and FZD10-mRNA level was achieved in FZD10-mRNA silenced cells and in their corresponding exosomes and, concomitantly a significant decrease in viability of the silenced cells compared to their respective controls was observed. Interestingly, the incubation of silenced cells with exosomes extracted from culture medium of the same untreated cells promoted a remarkable restoration of the cell viability and, also, of the FZD10 and FZD10-mRNA level, thus indicating that the FZD10 and FZD10-mRNA delivering exosomes may be potential messengers of cancer reactivation and play an active role in long-distance metastatization

The central reason behind emergence of clinically-detectable tumors is evasion from immune surveillance due to lack of cancer cells surface membrane expression of tumor-specific peptides in association with MHC class I molecules, concealment of natural killer cells-activating molecules, and absence of inflammation resulting from inefficient stimulation of innate immunity receptors and co-stimulatory molecules. The tumor microenvironment (TME) also contributes to tumor initiation, progression and resistance to therapeutic interventions because of its dense, fibrogenic, barrier-like composition, aberrant vasculature, and production of cytokines and chemokines responsible for recruitment of immune suppressive cells, notably myeloid-derived suppressor cells, M2 macrophages, regulatory T cells, extracellular trap-forming neutrophils, and cancer-associated fibroblasts. We herein show that the relentless efforts and strategies to overcome the TME elusive tumor-promoting impact produced contrasting, opposed, controversial effects, characterized by limited efficacy and proven adversity, and most importantly deterred from attempts to discover and counteract the fundamental inherent mechanisms initiating, and not consequent to, carcinogenesis.