Exploring Small Extracellular Vesicles for Precision Medicine in Prostate Cancer

Improving dermal fibroblast-to-epidermis communications and aging wound repair through extracellular vesicle-mediated delivery of Gstm2 mRNA

Skin aging is characterized by the disruption of skin homeostasis and impaired skin injury repair. Treatment of aging skin has long been limited by the unclear intervention targets and delivery techniques. Engineering extracellular vesicles (EVs) as an upgraded version of natural EVs holds great potential in regenerative medicine. In this study, we found that the expression of the critical antioxidant and detoxification gene Gstm2 was significantly reduced in aging skin. Thus, we constructed the skin primary fibroblasts-derived EVs encapsulating Gstm2 mRNA (EVsGstm2), and found that EVsGstm2 could significantly improve skin homeostasis and accelerate wound healing in aged mice. Mechanistically, we found that EVsGstm2 alleviated oxidative stress damage of aging dermal fibroblasts by modulating mitochondrial oxidative phosphorylation, and promoted dermal fibroblasts to regulate skin epidermal cell function by paracrine secretion of Nascent Polypeptide-Associated Complex Alpha subunit (NACA). Furthermore, we confirmed that NACA is a novel skin epidermal cell protective molecule that regulates skin epidermal cell turnover through the ROS-ERK-ETS-Cyclin D pathway. Our findings demonstrate the feasibility and efficacy of EVs-mediated delivery of Gstm2 for aged skin treatment and unveil novel roles of GSTM2 and NACA for improving aging skin.

Correlation between membrane proteins and sizes of extracellular vesicles and particles: A potential signature for cancer diagnosis

Extracellular vesicles and particles (EVPs) are recognized as ideal liquid biopsy tools for cancer detection, and membrane proteins are commonly used EVP biomarkers. However, bulk analysis of EVP membrane protein biomarkers typically fails to meet the clinical requirement for diagnostic accuracy. We investigated the correlation between the membrane protein expression level, the binding kinetics to aptamers and the sizes of EVPs with interferometric plasmonic microscopy (iPM), and demonstrated the implementation of the correlative signature to determine cancer types. Using EVPs collected from both cell model and clinical plasma samples with liver, lung, breast, or prostate cancer, we found that the selective set of membrane protein expression levels of five protein markers and their binding kinetics were highly heterogeneous across various sizes of EVPs, resulting in the low overall accuracy (<50%) in cancer classification with bulk analysis of all populations. By grouping the EVPs into three subpopulations according to their sizes, the overall accuracy could be increased to about 70%. We further grouped the EVPs into subpopulations with a 10 nm interval in sizes and analysed the correlation between the membrane proteins and sizes with a machine learning algorithm. The results show that the overall accuracy to discriminate cancer types could be improved to 85%. Therefore, this work highlights the significance of size-dependent subtyping of EVPs and suggests that the correlation between the selective set of membrane proteins and sizes of EVP can serve as a signature for clinical cancer diagnosis.

Medium Extracellular Vesicles—A Qualitative and Quantitative Biomarker of Prostate Cancer

For years, the diagnosis of prostate cancer has been understated. Despite the relatively low mortality rate, prostate cancer is still one of the most common neoplasms in men, which proves the need for continuous improvements in the diagnostics of this disease. New biomarkers may address these challenges in the form of extracellular vesicles (EV) secreted by prostate cancer cells. The available literature in the PubMed, SCOPUS, and ResearchGate databases from the last ten years was analyzed using search phrases such as extracellular vesicles, microparticles, microvesicles, cancer biomarkers, and prostate cancer. Then, the research was selected in terms of the size of the tested EVs (the EV medium of 100–1000 nm diameter, was taken into account), the latest versions of the literature were selected and compiled, and their results were compared. The group of extracellular vesicles contain a substantial amount of genetic information that can be used in research on the specificity of prostate cancer and other cancers. So far, it has been shown that EVs produced by PCa cells express proteins specific for these cells, which, thanks to their specificity, can make EV useful biomarkers of prostate cancer. Moreover, the importance of the quantitative release of EV from PCa cells has been demonstrated, which may be necessary to diagnose prostate cancer malignancy. Each method positively correlates with Gleason’s results and is even characterized by greater diagnostic sensitivity. Medium extracellular vesicles are a promising research material, and their specificity and sensitivity may allow them to be used in future prostate cancer diagnostics as biomarkers.

Using single-vesicle technologies to unravel the heterogeneity of extracellular vesicles

Extracellular vesicles (EVs) are heterogeneous lipid containers with a complex molecular cargo comprising several populations with unique roles in biological processes. These vesicles are closely associated with specific physiological features, which makes them invaluable in the detection and monitoring of various diseases. EVs play a key role in pathophysiological processes by actively triggering genetic or metabolic responses. However, the heterogeneity of their structure and composition hinders their application in medical diagnosis and therapies. This diversity makes it difficult to establish their exact physiological roles, and the functions and composition of different EV (sub)populations. Ensemble averaging approaches currently employed for EV characterization, such as western blotting or 'omics' technologies, tend to obscure rather than reveal these heterogeneities. Recent developments in single-vesicle analysis have made it possible to overcome these limitations and have facilitated the development of practical clinical applications. In this review, we discuss the benefits and challenges inherent to the current methods for the analysis of single vesicles and review the contribution of these approaches to the understanding of EV biology. We describe the contributions of these recent technological advances to the characterization and phenotyping of EVs, examination of the role of EVs in cell-to-cell communication pathways and the identification and validation of EVs as disease biomarkers. Finally, we discuss the potential of innovative single-vesicle imaging and analysis methodologies using microfluidic devices, which promise to deliver rapid and effective basic and practical applications for minimally invasive prognosis systems.

Evaluating the role of extracellular vesicles as a biomarker under transmission electron microscope in prostate cancer and benign prostate hyperplasia patients

OBJECTIVES

To our knowledge, EVs (extracellular vesicles) are heterogenous encapsulated nanoparticles generated by the biological cells. EVs can be found in blood, urine and tissue of origin. They contain DNAs, RNAs, proteins specific to the cell of origin. It has been found that in PCa, increase in number of EVs can modulate phenotype and function of the recipient cells.

METHODS

This prospective randomized double-blind pilot study was conducted in the SMS Medical College, Jaipur in collaboration with All India Institute of Medical Sciences, New Delhi. For morphometric analysis, the number of extracellular vesicles per micrograph were counted under transmission electron microscope.

RESULTS

Out of 16 patients taken in our study, six were in group 1 (BPH group) and 10 were in group 2 (PCa group). The mean number of EVs was significantly higher in the cells of group 2 in comparison to the group 1. Among the PCa patients, mean number of EVs were 25, 30, 35, 43, 46 for the Gleason score 6, 7, 8, 9, 10 respectively. In our study the mean number of EVs in the newly diagnosed PCa group was less as compared to the CSPC and CRPC group.

CONCLUSIONS

EVs are membrane bound particles shed regularly from the cells in the extracellular milieu under normal physiological and pathological conditions. In our study the number of EVs were more in the PCa cells in comparison with the BPH cells and among the PCa cells they bear a positive correlation with the Gleason score, thus EVs have the potential to become a biomarker.

Urinary Exosomes in Prostate Cancer

The analysis of liquid biopsy as a source of diagnostic, prognostic, and predictive biomarkers is still object of the main research in the prostate cancer field. Many advantages, such as less invasiveness compared to plasma or serum analysis and the rich content, confer to urine a role as an interesting fluid to be analysed especially in urological diseases. Here we report a workflow focused on profile, concentration, and protein surface characterization of EVs from urinary supernatant.

EV Separation: Release of Intact Extracellular Vesicles Immunocaptured on Magnetic Particles

Extracellular vesicles (EVs) have attracted considerable interest due to their role in cell-cell communication, disease diagnosis, and drug delivery. Despite their potential in the medical field, there is no consensus on the best method for separating micro- and nanovesicles from cell culture supernatant and complex biological fluids. Obtaining a good recovery yield and preserving physical characteristics is critical for the diagnostic and therapeutic use of EVs. The separation of a single class of EVs, such as exosomes, is complex because blood and cell culture media contain many nanoparticles in the same size range. Methods that exploit immunoaffinity capture provide high-purity samples and overcome the issues of currently used separation methods. However, the release of captured nanovesicles usually requires harsh conditions that hinder their use in certain types of downstream analysis. A novel capture and release approach for small extracellular vesicles (sEVs) is presented based on DNA-directed immobilization of antiCD63 antibody. The flexible DNA linker increases the capture efficiency and allows for releasing EVs by exploiting the endonuclease activity of DNAse I. This separation protocol works under mild conditions, enabling the release of vesicles suitable for analysis by imaging techniques. In this study, sEVs recovered from plasma were characterized by established techniques for EV analysis, including nanoparticle tracking and transmission electron microscopy.

Quality Assessment and Comparison of Plasma-Derived Extracellular Vesicles Separated by Three Commercial Kits for Prostate Cancer Diagnosis

Introduction

Current standard biomarkers in clinic are not specific enough for prostate cancer (PCa) diagnosis. Extracellular vesicles (EVs) are nano-scale vesicles released by most mammalian cells. EVs are promising biomarker source for PCa liquid biopsy due to its minimal invasive approach, rich information and improved accuracy compared to the clinical standard prostate-specific antigen (PSA). However, current EV separation methods cannot separate pure EVs and the quality characteristics from these methods remain largely unknown. In this study, we evaluated the quality characteristics of human plasma-derived EVs by comparing three clinical suitable separation kits.

Methods

We combined EV separation by commercial kits with magnetic beads capture and flow cytometry analysis, and compared three kits including ExoQuick Ultra based on precipitation and qEV35 and qEV70 based on size exclusion chromatography (SEC).

Results

Our results indicated that two SEC kits provided higher EV purity and lower protein contamination compared to ExoQuick Ultra precipitation and that qEV35 demonstrated a higher EV yield but lower EV purity compared to qEV70. Particle number correlated very well particularly with CD9/81/63 positive EVs for all three kits, which confirms that particle number can be used as the estimate for EV amount. At last, we found that several EV metrics including total EVs and PSA-specific EVs could not differentiate PCa patients from health controls.

Conclusion

We provided a systematic workflow for the comparison of three separation kits as well as a general analysis process in clinical laboratories for EV-based cancer diagnosis. Better EV-associated cancer biomarkers need to be explored in the future study with a larger cohort.

Role of exosome in autoimmunity, with a particular emphasis on rheumatoid arthritis

Cell-derived exosomes are identified as carriers of lipids, proteins, and genetic materials that participate in cell-cell signal communication, biological process, and cell signaling. Also, their involvement has been reported in a vast array of disorders and inflammatory conditions such as autoimmune diseases. Rheumatoid arthritis (RA), a common cause of joint disorder, is an inflammation-based disease in which the precise understanding of its pathogenesis needs to be further investigated. Also, there is only a palliative care approach for the alleviation of RA symptoms. This paper discusses the recent advances in the biology of exosomes in autoimmune disorders especially in RA, and also provides a new line of research for arthritis therapy using exosomes.

Astrocyte regional diversity in ALS includes distinct aberrant phenotypes with common and causal pathological processes

Astrocytes are major contributors of motor neuron (MN) degeneration in amyotrophic lateral sclerosis (ALS). We investigated whether regional and cell maturation differences influence ALS astrocyte malfunction. Spinal and cortical astrocytes from SOD1G93A (mSOD1) 7-day-old mice were cultured for 5 and 13 days in vitro (DIV). Astrocyte aberrancies predominated in 13DIV cells with region specificity. 13DIV cortical mSOD1 astrocytes showed early morphological changes and a predominant reactive and inflammatory phenotype, while repressed proteins and genes were found in spinal cells. Inflammatory-associated miRNAs, e.g. miR-155/miR-21/miR-146a, were downregulated in the first and upregulated in the later ones. Interestingly, depleted miR-155/miR-21/miR-146a in small extracellular vesicles (sEVs/exosomes) was a common pathological feature. Cortical mSOD1 astrocytes induced late apoptosis and kinesin-1 downregulation in mSOD1 NSC-34 MNs, whereas spinal cells upregulated dynein, while decreased nNOS and synaptic-related genes. Both regional-distinct mSOD1 astrocytes enhanced iNOS gene expression in mSOD1 MNs. We provide information on the potential contribution of astrocytes to ALS bulbar-vs. spinal-onset pathology, local influence on neuronal dysfunction and their shared miRNA-depleted exosome trafficking. These causal and common features may have potential therapeutic implications in ALS. Future studies should clarify if astrocyte-derived sEVs are active players in ALS-related neuroinflammation and glial activation.

Analysis of Neat Biofluids Obtained During Cardiac Surgery Using Nanoparticle Tracking Analysis: Methodological Considerations

Small extracellular vesicles (sEVs) are those nanovesicles 30-150 nm in size with a role in cell signalling and potential as biomarkers of disease. Nanoparticle tracking analysis (NTA) techniques are commonly used to measure sEV concentration in biofluids. However, this quantification technique can be susceptible to sample handing and machine settings. Moreover, some classes of lipoproteins are of similar sizes and could therefore confound sEV quantification, particularly in blood-derived preparations, such serum and plasma. Here we have provided methodological information on NTA measurements and systematically investigated potential factors that could interfere with the reliability and repeatability of results obtained when looking at neat biofluids (i.e., human serum and pericardial fluid) obtained from patients undergoing cardiac surgery and from healthy controls. Data suggest that variables that can affect vesicle quantification include the level of contamination from lipoproteins, number of sample freeze/thaw cycles, sample filtration, using saline-based diluents, video length and keeping the number of particles per frame within defined limits. Those parameters that are of less concern include focus, the "Maximum Jump" setting and the number of videos recorded. However, if these settings are clearly inappropriate the results obtained will be spurious. Similarly, good experimental practice suggests that multiple videos should be recorded. In conclusion, NTA is a perfectible, but still commonly used system for sEVs analyses. Provided users handle their samples with a highly robust and consistent protocol, and accurately report these aspects, they can obtain data that could potentially translate into new clinical biomarkers for diagnosis and monitoring of cardiovascular disease.

Role of miRNAs in prostate cancer: Do we really know everything?

Many different genetic alterations, as well as complex epigenetic interactions, are the basis of the genesis and progression of prostate cancer (CaP). This is the reason why until now the molecular pathways related to development of this cancer were only partly known, and even less those that determine aggressive or indolent tumour behaviour. MicroRNAs (miRNAs) represent a class of about 22 nucleotides long, small non-coding RNAs, which are involved in gene expression regulation at the post-transcriptional level. MiRNAs play a crucial role in regulating several biological functions and preserving homeostasis, as they carry out a wide modulatory activity on various molecular signalling pathways. MiRNA genes are placed in cancer-related genomic regions or in fragile sites, and they have been proven to be involved in the main steps of carcinogenesis as oncogenes or oncosuppressors in many types of cancer, including CaP. We performed a narrative review to describe the relationship between miRNAs and the crucial steps of development and progression of CaP. The aims of this study were to improve the knowledge regarding the mechanisms underlying miRNA expression and their target genes, and to contribute to understanding the relationship between miRNA expression profiles and CaP.

Exosomes in Prostate Cancer Diagnosis, Prognosis and Therapy

Prostate cancer (PCa) is the second most common cause of cancer-related mortality among men in the developed world. Conventional anti-PCa therapies are not effective for patients with advanced and/or metastatic disease. In most cases, cancer therapies fail due to an incomplete depletion of tumor cells, resulting in tumor relapse. Exosomes are involved in tumor progression, promoting the angiogenesis and migration of tumor cells during metastasis. These structures contribute to the dissemination of pathogenic agents through interaction with recipient cells. Exosomes may deliver molecules that are able to induce the transdifferentiation process, known as “epithelial to mesenchymal transition”. The composition of exosomes and the associated possibilities of interacting with cells make exosomes multifaceted regulators of cancer development. Extracellular vesicles have biophysical properties, such as stability, biocompatibility, permeability, low toxicity and low immunogenicity, which are key for the successful development of an innovative drug delivery system. They have an enhanced circulation stability and bio-barrier permeation ability, and they can therefore be used as effective chemotherapeutic carriers to improve the regulation of target tissues and organs. Exosomes have the capacity to deliver different types of cargo and to target specific cells. Chemotherapeutics, natural products and RNA have been encapsulated for the treatment of prostate cancers.

Exosomal microRNAs as liquid biopsy biomarkers in prostate cancer

Prostate cancer (PCa) is the most commonly diagnosed solid-organ cancer in males. The PSA testing may cause overdiagnosis and overtreatment for PCa patients. There is an urgent need for new biomarkers with greater discriminative precision for diagnosis and risk-stratification, to select for prostate biopsy and treatment of PCa. Liquid biopsy is a promising field with the potential to provide comprehensive information on the genetic landscape at diagnosis and to track genomic evolution over time in order to tailor the therapeutic choices at all stages of PCa. Exosomes, containing RNAs, DNAs and proteins, have been shown to be involved in tumour progression and a rich potential source of tumour biomarkers, especially for profiling analysis of their miRNAs content. In this review, we summarise the exosomal miRNAs in PCa diagnosis, prognosis and management, and further discuss their possible technical challenges associated with isolating PCa-specific exosomes.

Challenges and opportunities in exosome research-Perspectives from biology, engineering, and cancer therapy

Exosomes are small (∼30-140 nm) lipid bilayer-enclosed particles of endosomal origin. They are a subset of extracellular vesicles (EVs) that are secreted by most cell types. There has been growing interest in exosome research in the last decade due to their emerging role as intercellular messengers and their potential in disease diagnosis. Indeed, exosomes contain proteins, lipids, and RNAs that are specific to their cell origin and could deliver cargo to both nearby and distant cells. As a result, investigation of exosome cargo contents could offer opportunities for disease detection and treatment. Moreover, exosomes have been explored as natural drug delivery vehicles since they can travel safely in extracellular fluids and deliver cargo to destined cells with high specificity and efficiency. Despite significant efforts made in this relatively new field of research, progress has been held back by challenges such as inefficient separation methods, difficulties in characterization, and lack of specific biomarkers. In this review, we summarize the current knowledge in exosome biogenesis, their roles in disease progression, and therapeutic applications and opportunities in bioengineering. Furthermore, we highlight the established and emerging technological developments in exosome isolation and characterization. We aim to consider critical challenges in exosome research and provide directions for future studies.

Modern urology perspectives on prostate cancer biomarkers

Introduction

Prostate cancer (PCa) is the most common type of cancer among men in Europe. Current recommendations for screening and diagnosis are based on prostate-specific antigen (PSA) measurements and the digital rectal examination (DRE). Both of them are triggers for prostate biopsy. Limited specificity of the PSA test brings, however, a need to develop new, better diagnostic tools. Several commercially available variations of the PSA test including: prostate health index (PHI), 4Kscore as well as molecular PCA3 score, have already revealed its value, lowering the number of unnecessary biopsies.

Material and methods

This review summarizes published results of the current most promising, clinically proven and experimentally evaluated PCa biomarkers which have potential for creation of new diagnostic tests.

Results

In the last few years new approaches for providing significantly better biomarkers, an alternative to PSA, have been introduced. Modern biomarkers show improvement in being used as not only a diagnosis procedure, but also for staging, evaluating aggressiveness and managing the therapeutic process. The most promising group are molecular markers, among them microRNAs(miRNAs) and long noncoding RNAs (lncRNAs) are most frequent. Their superiority, over standard PSA, in predicting tumor formation in early stages, and clinically non-symptomatic metastases has been noticed. Extracellular vesicles presence in biofluids have brought focus of many research groups, indicating their potential significance. This group of nanoparticles has potential not only in diagnostic and therapy management process, but also as a potential therapeutic target.

Conclusions

Finding better PCa biomarkers, replacing the current PSA measurement, is firmly needed in modern urology practice.

Emerging Biomarkers in Bladder Cancer Identified by Network Analysis of Transcriptomic Data

Bladder cancer is a very common malignancy. Although new treatment strategies have been developed, the identification of new therapeutic targets and reliable diagnostic/prognostic biomarkers for bladder cancer remains a priority. Generally, they are found among differentially expressed genes between patients and healthy subjects or among patients with different tumor stages. However, the classical approach includes processing these data taking into consideration only the expression of each single gene regardless of the expression of other genes. These complex gene interaction networks can be revealed by a recently developed systems biology approach called Weighted Gene Co-expression Network Analysis (WGCNA). It takes into account the expression of all genes assessed in an experiment in order to reveal the clusters of co-expressed genes (modules) that, very probably, are also co-regulated. If some genes are co-expressed in controls but not in pathological samples, it can be hypothesized that a regulatory mechanism was altered and that it could be the cause or the effect of the disease. Therefore, genes within these modules could play a role in cancer and thus be considered as potential therapeutic targets or diagnostic/prognostic biomarkers. Here, we have reviewed all the studies where WGCNA has been applied to gene expression data from bladder cancer patients. We have shown the importance of this new approach in identifying candidate biomarkers and therapeutic targets. They include both genes and miRNAs and some of them have already been identified in the literature to have a role in bladder cancer initiation, progression, metastasis, and patient survival.