Extracellular vesicles (EVs), whose main subtypes are exosomes, microparticles, and apoptotic bodies, are secreted by all cells and harbor biomolecules such as DNA, RNA, and proteins. They function as intercellular messengers and, depending on their cargo, may have multiple roles in cancer development. Thymidine kinase 1 (TK1) is a cell cycle-dependent enzyme used as a biomarker for cell proliferation. TK1 is usually elevated in cancer patients\' serum, making the enzyme a valuable tumor proliferation biomarker that strongly correlates with cancer stage and metastatic capabilities. Here, we investigated the presence of TK1 in EVs derived from three prostate cancer cell lines with various p53 mutation statuses (LNCaP, PC3, and DU145), EVs from the normal prostate epithelial cell line RWPE-1 and EVs isolated from human seminal fluid (prostasomes). We measured the TK1 activity by a real-time assay for these EVs. We demonstrated that the TK1 enzyme activity is higher in EVs derived from the malignant cell lines, with the highest activity from cells deriving from the most aggressive cancer, compared to the prostasomes and RWPE-1 EVs. The measurement of TK1 activity in EVs may be essential in future prostate cancer studies.

The investigation of biomarkers is constantly evolving. New molecules and molecular assemblies, such as soluble and particulate complexes, emerged as biomarkers from basic research and investigation of different proteomes, genomes, and glycomes. Extracellular vesicles (EVs), and glycans, complex carbohydrates are ubiquitous in nature. The composition and structure of both reflect physiological state of paternal cells and are strikingly changed in diseases. The EV-associated glycans, alone or in combination with soluble glycans in related biological fluids, used as analytes, aim to capture full complex biomarker picture, enabling its use in different clinical settings. Bringing together EVs and glycans can help to extract meaningful data from their extreme and distinct heterogeneities for use in the real-time diagnostics. The glycans on the surface of EVs could mark their subpopulations and establish the glycosignature, the solubilisation signature and molecular patterns. They all contribute to a new way of looking at and looking for composite biomarkers.

The prostate of the koala (Phascolarctos cinereus), and of marsupials more generally, is the primary contributor of seminal fluid, yet comparatively little is known about its microanatomy or biochemistry. This study explored evidence of parenchymal segmentation of the koala prostate. The prostate of three sexually mature koalas were processed for histopathology, histochemistry (Masson\'s trichrome, Alcian Blue, periodic acid Schiff staining), and immunohistochemistry using basal (tumor protein 63, cytokeratin 14) and luminal (cytokeratin 8/18, prostate specific antigen, androgen receptor) markers. Results confirmed clear segmentation of the koala prostate into three zones, anterior, central, and posterior, characterized by differences in the proportion of glandular tissue, as well as the thickness of collagen fibers; there were also distinct differences in the secretions produced in each zone. Based on immunohistochemistry, the koala prostate showed evidence of both basal proliferative and luminal secretory cells. The ratio of cell types varied across the three segments, with the central segment housing the highest density of basal cells. Globular bodies produced in the anterior zone were shown to possess the same markers as those described for human prostasomes. This study is the first to comprehensively document the marsupial prostate in terms of microanatomy and corresponding immunohistochemistry. While further biochemical analysis, such as proteomics of each segment will better define the relative functions of each tissue, the data presented here are consistent with the hypothesis that the koala prostate potentially represents an example of an ontological stage in the evolutionary differentiation of male eutherian accessory glands.

To review the role of extracellular vesicles (EVs) released from the male reproductive tract and their impact on developing sperm. We discuss how sperm exiting the seminiferous tubules, although developmentally mature, require further modification. Acquisition of various functions including increased motility, transfer of cargoes and ability to undertake the acrosome reaction is mediated through the interaction between sperm and EVs.
A review of the literature identified that EVs are released from different portions of the male reproductive tract, notably the epididymis and prostate. These EVs interact with sperm as they pass from the seminiferous tubules to the epididymis and vas deferens prior to ejaculation.
EVs are small lipid-bound particles carrying bespoke RNA, protein and lipid cargoes. These cargoes are loaded based on the state of the parent cell and are used to communicate with recipient cells. In sperm, these cargoes are essential for post-testicular modification.
Interactions between developing sperm and EVs are important for the subsequent function of sperm. Prior to ejaculation, these interactions confer important changes for the post-testicular modification and development of sperm. Little is known about the interaction between EVs from the testes and the spermatogonial stem cell niche or developing sperm within the seminiferous tubules. However, the numerous roles of EVs in the post-testicular modification of sperm have led many to suspect that they may also play important roles in developing sperm within the testes.
Sperm are crucial for successful fertility. In order to do this, they must be able to swim a large distance to meet the egg in the female reproductive tract and fertilise it. Once released from the testes, sperm may appear to be fully developed, but this is not the case. Several important modifications are required in order for them to swim and fertilise an egg. These modifications are carried out by sending sperm small packages from other cells which contain messages and cargo. We discuss the release of these small packages along with different parts of the male reproductive tract and how they change the way sperm behave and function. This article reviews the literature and known functions of these packages called extracellular vesicles, which are released by the male reproductive tract and modify sperm, transforming their function, before they are ejaculated.

Extracellular Vesicles (EVs) are membrane-limited particles containing proteins, lipids, metabolites and nucleic acids that are secreted by healthy and cancerous cells. These vesicles are very heterogeneous in size and content and mediate a variety of biological functions. Three subtypes of EV have been described in the male genital tract: microvesicles, myelinosomes and exosomes. Each type of EVs depends on the location of secretion such as the testis, prostate or epididymis. It has been shown that EVs can fuse together and deliver information to recipient cells, for example spermatozoa in the male genital tract. Cryo-electron microscopy remains the reference technique for determining EV morphology, but quantifying the absolute concentration of these EVs in biological fluids remains a challenge from a clinical point of view. The field of bio detection has considerably increased with the introduction of nanomaterials in biosensors and will provide a better understanding of the impact of these EVs. However, functional modifications of male gametes result from interactions with the components of the intraluminal fluid all along the genital tract and depend on the secretion and absorption of proteins and lipids from the local microenvironment. We cannot therefore exclude the possibility of epigenetic modulation of the information that will be transmitted to the embryo and therefore to the next generation via EVs.
RéSUMé: Les Vésicules Extracellulaires (VE) sont des constituants d’origine membranaire contenant des protéines solubles ou membranaires, des lipides, des métabolites ou des acides nucléiques. Ces vésicules sont très hétérogènes en taille et en contenu. Trois catégories de VE ont été décrites dans le tractus génital mâle: les microvésicules, les myélinosomes et les exosomes. Les types de VE sont différents selon le lieu de production testiculaire, prostatique ou encore épididymaire. Il a été montré que les VE peuvent fusionner et délivrer une information à la cellule réceptrice, en l’occurrence le spermatozoïde dans le tractus génital mâle. La cryo-microscopie électronique reste la technique de référence pour déterminer la morphologie des VE mais la quantification de la concentration absolue de ces VE dans les liquides biologiques reste un challenge dans le cadre d’une approche clinique. Le domaine de la biodétection s’est. considérablement développé avec l’introduction des nanomatériaux dans les biocapteurs et va permettre de mieux comprendre l’impact de ces VE. Or les modifications fonctionnelles des gamètes mâles résultent d’interactions avec les composants du liquide intraluminal tout le long du tractus génital et dépendent de la sécrétion et de l’absorption de protéines et de lipides du microenvironnement local. On ne peut donc pas exclure la possibilité d’une modulation épigénétique des informations qui seront transmises à l’embryon donc à la génération suivante via les VE.

BACKGROUND: Exosomes are nano-sized membrane vesicles, secreted by different types of cells into the body\'s biological fluids. They are found in abundance in semen as compared to other fluids. Exosomes contain a cargo of lipid molecules, proteins, phospholipids, cholesterol, mRNAs, and miRNAs. Each molecule of seminal exosomes (SE) has a potential role in male reproduction for childbirth. Many potential candidates are available within the seminal exosomes that can be used as diagnostic markers for various diseases or syndromes associated with male reproduction. Also these seminal exospmes play a major role in female reproductive tract for effective fertilization.
OBJECTIVE: The aim of this review is to focus on the advancement of human seminal exosomal research and its various properties.
METHODS: We used many databases like Scopus, Google scholar, NCBI-NLM and other sources to filter the articles of interest published in exosomes. We used phrases like \"Exosomes in human semen\", \"Composition of exosomes in human semen\" and other relevant words to filter the best articles.
RESULTS: Seminal exosomes play a major role in sperm functions like cell-to-cell communication, motility of the sperm cells, maintaining survival capacity for the sperm in the female reproductive tract and spermatogenesis. Also, seminal exosomes are used as a carrier for many regulatory elements using small RNA molecules. miRNAs of the seminal exosomes can be used as a diagnostic marker for prostate cancer instead of prostate specific antigen (PSA). Epididymosomes can be used as a biomarker for reproductive diseases and male infertility.
CONCLUSIONS: Seminal exosomes could be used as biological markers for various reproductive disorders, male infertility diagnosis, and it can be used in anti-retroviral research for the identification of novel therapeutics for HIV-1 infection and transmission.

Prostasomes, a secretory particle from prostate gland in human seminal fluid plays a role in enhancing the fertility and its absence or less presence will lead to male infertility. Very few fertility associated proteins were detected in prostasomes. In order to isolate the prostasomes from ejaculated semen, the characterization was done using biochemical, molecular and in silico methods. The objective of current work on prostasomes is to identify a novel protein biomarker for the diagnosis and prognosis of male infertility. Semen samples were collected, primary semen analysis was done and prostasomes were isolated from ejaculated semen of fertile and infertile categories. Biochemical parameters like protein content, total antioxidant capacity, cholesterol content were evaluated in prostasomes. The critical expressed protein was identified by using SDS page and MALDI TOF techniques. Isolated particle from the semen samples was confirmed as prostasomes from SEM analysis and particle size analyzer. In MALDI results, the maximum hit was obtained against Clusterin that been reported to be involved in capacitation and motility of sperm. Structural modeling and molecular dynamics were carried out on Clusterin and elucidate the structural insights in the dynamic system. Overall, our study reported the novel biomarker Clusterin in prostasomes for diagnosis and prognosis of male infertility.Communicated by Ramaswamy H. Sarma.

Extracellular vesicles (EVs) are small lipid bound structures released from cells containing bioactive cargoes. Both the type of cargo and amount loaded varies compared to that of the parent cell. The characterisation of EVs in cancers of the male urogenital tract has identified several cargoes with promising diagnostic and disease monitoring potential. EVs released by cancers of the male urogenital tract promote cell-to-cell communication, migration, cancer progression and manipulate the immune system promoting metastasis by evading the immune response. Their use as diagnostic biomarkers represents a new area of screening and disease detection, potentially reducing the need for invasive biopsies. Many validated EV cargoes have been found to have superior sensitivity and specificity than current diagnostic tools currently in use. The use of EVs to improve disease monitoring and develop novel therapeutics will enable clinicians to individualise patient management in the exciting era of personalised medicine.

Body fluids contain many populations of extracellular vesicles (EV) that differ in size, cellular origin, molecular composition, and biological activities. EV in seminal plasma are in majority originating from prostate epithelial cells, and hence are also referred to as prostasomes. Nevertheless, EV are also contributed by other accessory sex glands, as well as by the testis and epididymis. In a previous study, we isolated EV from seminal plasma of vasectomized men, thereby excluding contributions from the testis and epididymis, and identified two distinct EV populations with diameters of 50 and 100 nm, respectively. In the current study, we comprehensively analyzed the protein composition of these two EV populations using quantitative Liquid Chromatography-Mass Spectrometry (LC-MS/MS). In total 1558 proteins were identified. Of these, ≈45% was found only in the isolated 100 nm EV, 1% only in the isolated 50 nm EV, and 54% in both 100 nm and 50 nm EV. Gene ontology (GO) enrichment analysis suggest that both originate from the prostate, but with distinct biogenesis pathways. Finally, nine proteins, including KLK3, KLK2, MSMB, NEFH, PSCA, PABPC1, TGM4, ALOX15B, and ANO7, with known prostate specific expression and alternate expression levels in prostate cancer tissue were identified. These data have potential for the discovery of EV associated prostate cancer biomarkers in blood.

The participation of extracellular vesicles in many cellular processes, including reproduction, is unquestionable. Although currently, the tetraspanin proteins found in extracellular vesicles are mostly applied as markers, increasing evidence points to their role in extracellular vesicle biogenesis, cargo selection, cell targeting, and cell uptake under both physiological and pathological conditions. In this review, we bring other insight into the involvement of tetraspanin proteins in extracellular vesicle physiology in mammalian reproduction. We provide knowledge regarding the involvement of extracellular vesicle tetraspanins in these processes in somatic cells. Furthermore, we discuss the future direction towards an understanding of their functions in the tissues and fluids of the mammalian reproductive system in gamete maturation, fertilization, and embryo development; their involvement in mutual cell contact and communication in their complexity.