Tumor-derived extracellular vesicles and microRNAs: Functional roles, diagnostic, prognostic and therapeutic options

Effect of human bone marrow mesenchymal stem cell-derived microvesicles on the apoptosis of the multiple myeloma cell line U266

BACKGROUND

Microvesicles are membraned particles produced by different types of cells recently investigated for anticancer purposes. The current study aimed to investigate the effects of human bone marrow mesenchymal stem cell-derived microvesicles (BMSC-MVs) on the multiple myeloma cell line U266. BMSC-MVs were isolated from BMSCs via ultracentrifugation and characterized using transmission electron microscopy (TEM) and dynamic light scattering (DLS). U266 cells were treated with 15, 30, 60, and 120 µg/mL BMSC-MVs for three and seven days and the effects of treatment in terms of viability, cytotoxicity, and DNA damage were investigated via the MTT assay, lactate dehydrogenase (LDH) assay, and 8‑hydroxy-2'-deoxyguanosine (8‑OHdG) measurement, respectively. Moreover, the apoptosis rate of the U266 cells treated with 60 µg/mL BMSC-MVs was also assessed seven days following treatment via flow cytometry. Ultimately, the expression level of BCL2, BAX, and CCND1 by the U266 cells was examined seven days following treatment with 60 µg/mL BMSC-MVs using qRT-PCR.

RESULTS

BMSC-MVs had an average size of ~ 410 nm. According to the MTT and LDH assays, BMSC-MV treatment reduced the U266 cell viability and mediated cytotoxic effects against them, respectively. Moreover, elevated 8‑OHdG levels following BMSC-MV treatment demonstrated a dose-dependent increase of DNA damage in the treated cells. BMSC-MV-treated U266 cells also exhibited an increased apoptosis rate after seven days of treatment. The expression level of BCL2 and CCND1 decreased in the treated cells whereas the BAX expression demonstrated an incremental pattern.

CONCLUSIONS

Our findings accentuate the therapeutic benefit of BMSC-MVs against the multiple myeloma cell line U266 and demonstrate how microvesicles could be of therapeutic advantage. Future in vivo studies could further corroborate these findings.

SERS microfluidic chip integrated with double amplified signal off-on strategy for detection of microRNA in NSCLC

In this work, based on Fe3O4@AuNPs and double amplified signal Off-On strategy, a simple and sensitive SERS microfluidic chip was constructed to detect microRNA associated with non-small cell lung cancer (NSCLC). Fe3O4@AuNPs have two advantages of SERS enhanced and magnetic adsorption, the introduction of microfluidic chip can realize double amplification of SERS signal. First, the binding of complementary ssDNA and hpDNA moved the Raman signaling molecule away from Fe3O4@AuNPs, at which point the signal was turned off. Second, in the presence of the target microRNA, they were captured by complementary ssDNA and bound to them. HpDNA restored the hairpin conformation, the Raman signaling molecule moved closer to Fe3O4@AuNPs. At this time, the signal was turned on and strong Raman signal was generated. And last, through the magnetic component of SERS microfluidic chip, Fe3O4@AuNPs could be enriched to realize the secondary enhancement of SERS signal. In this way, the proposed SERS microfluidic chip can detect microRNA with high sensitivity and specificity. The corresponding detection of limit (LOD) for miR-21 versus miR-125b was 6.38 aM and 7.94 aM, respectively. This SERS microfluidic chip was promising in the field of early detection of NSCLC.

Improving targeted small molecule drugs to overcome chemotherapy resistance

BACKGROUND

Conventional cancer treatments face the challenge of therapeutic resistance, which causes poor treatment outcomes. The use of combination therapies can improve treatment results in patients and is one of the solutions to overcome this challenge. Chemotherapy is one of the conventional treatments that, due to the non-targeted and lack of specificity in targeting cancer cells, can cause serious complications in the short and long-term for patients by damaging healthy cells. Also, the employment of a wide range of strategies for chemotherapy resistance by cancer cells, metastasis, and cancer recurrence create serious problems to achieve the desired results of chemotherapy. Accordingly, targeted therapies can be used as a combination treatment with chemotherapy to both cause less damage to healthy cells, which as a result, they reduce the side effects of chemotherapy, and by targeting the factors that cause therapeutic challenges, can improve the results of chemotherapy in patients.

RECENT FINDINGS

Small molecules are one of the main targeted therapies that can be used for diverse targets in cancer treatment due to their penetration ability and characteristics. However, small molecules in cancer treatment are facing obstacles that a better understanding of cancer biology, as well as the mechanisms and factors involved in chemotherapy resistance, can lead to the improvement of this type of major targeted therapy.

CONCLUSION

In this review article, at first, the challenges that lead to not achieving the desired results in chemotherapy and how cancer cells can be resistant to chemotherapy are examined, and at the end, research areas are suggested that more focusing on them, can lead to the improvement of the results of using targeted small molecules as an adjunctive treatment for chemotherapy in the conditions of chemotherapy resistance and metastasis of cancer cells.

A validation study for the utility of serum microRNA as a diagnostic and prognostic marker in patients with osteosarcoma

In our previous study, osteosarcoma advanced locally, and metastasis was promoted through the secretion of large number of small extracellular vesicles, followed by suppressing osteoclastogenesis via the upregulation of microRNA (miR)-146a-5p. An additional 12 miRNAs in small extracellular vesicles were also detected ≥6× as frequently in high-grade malignancy with the capacity to metastasize as in those with a low metastatic potential. However, the utility of these 13 miRNAs for determining the prognosis or diagnosis of osteosarcoma has not been validated in the clinical setting. In the present study, the utility of these miRNAs as prognostic and diagnostic markers was therefore assessed. In total, 30 patients with osteosarcoma were retrospectively reviewed, and the survival rate was compared according to the serum miRNA levels in 27 patients treated with chemotherapy and surgery. In addition, to confirm diagnostic competency for osteosarcoma, the serum miRNA levels were compared with those in patients with other bone tumors (n=112) and healthy controls (n=275). The patients with osteosarcoma with high serum levels of several miRNAs (miR-146a-5p, miR-1260a, miR-487b-3p, miR-1260b and miR-4758-3p) exhibited an improved survival rate compared with those with low levels. In particular, patients with high serum levels of miR-1260a exhibited a significantly improved overall survival rate, metastasis-free survival rate and disease-free survival rate compared with those with low levels. Thus, serum miR-1260a may potentially be a prognostic marker for patients with osteosarcoma. Moreover, patients with osteosarcoma had higher serum miR-1261 levels than those with benign or intermediate-grade bone tumors and thus may be a potential therapeutic target, in addition to being useful for differentiating whether or not a bone tumor is high-grade. A larger investigation is required to clarify the actual utility of these miRNAs in the clinical setting.

Advances of exosomal miRNAs in the diagnosis and treatment of ovarian cancer

Ovarian cancer is a tumor with the highest fatalities among female malignant tumors. This disease has no typical symptoms in its early stage, and most of the patients are in an advanced stage when being treated. The treatment effect is poor and it is easy to develop chemotherapy resistance. Therefore, it is particularly urgent to clarify the pathogenesis of ovarian cancer, explore its early diagnosis of biomarkers, and discover new treatment methods. As a carrier of intercellular information and genetic material transfer, exosomes are widely distributed in body fluids (e.g. blood and urine), which are regarded as latent tumor markers and take effects on tumor occurrence and invasion. Several articles have recently signified that exosomal miRNAs are widely implicated in the formation of the ovarian cancer tumor microenvironment, disease initiation and progression, and the generation of chemotherapy resistance. This article reviews the research on exosomal miRNAs in ovarian cancer.

Identification of differentially expressed miRNAs derived from serum exosomes associated with gastric cancer by microarray analysis

AIMS

To explore the differentially expressed microRNAs (DEMs) in serum exosomes between gastric cancer (GC) patients and healthy people to provide new targets for GC diagnosis and treatment.

METHODS

DEMs in serum exosomes were screened by microarray analysis and verified by RT-qPCR. The target genes of DEMs were predicted using Targetscan and miRTarBase databases and then overlapped with the DEGs of STAD in TCGA database to obtain the common target genes. Biological function and pathway enrichment were analyzed using enrichr database, and a PPI network was constructed using STRING database. The potential target genes of DEMs were identified using the MCODE and cytoHubba plug-ins of Cytoscape software. Survival analysis were conducted using KMP and TCGA databases. The DEMs -target genes-pathways network was established using Cytoscape software. A Cox proportional hazards regression model formed by optimal target genes was used to access the reliability of this prediction process.

RESULTS

Three serum exosomal microRNAs (exo-miRNAs, has-miR-1273 g-3p, has-miR-4793-3p, has-miR-619-5p) were identified to be highly expressed in GC patients and performed excellent diagnostic ability. A total of 179 common target genes related to GC were predicted. They were mainly involved in 79 GO functional annotations and 6 KEGG pathways. The prognostic model formed by eight optimal target genes (TIMELESS, DNA2, MELK, CHAF1B, DBF4, PAICS, CHEK1 and NCAPG2), which were low-risk genes of GC, also performed perfect prognostic ability.

CONCLUSIONS

Serum exosomal has-miR-1273 g-3p, has-miR-4793-3p and has-miR-619-5p can be used as new diagnostic biomarkers for GC. Among them, serum exosomal hsa-miR-1273 g-3p / hsa-miR-4793-3p targets MELK and hsa-miR-619-5p targets NCAPG2 were identified as novel mechanisms involved in the development of GC. It provides new targets for the diagnosis and treatment of GC by exo-miRNAs.

Exosome-derived noncoding RNAs: Function, mechanism, and application in tumor angiogenesis

Exosomes are extracellular vesicles released by various cell types that perform various biological functions, mainly mediating communication between different cells, especially those active in cancer. Noncoding RNAs (ncRNAs), of which there are many types, were recently identified as enriched and stable in the exocrine region and play various roles in the occurrence and progression of cancer. Abnormal angiogenesis has been confirmed to be related to human cancer. An increasing number of studies have shown that exosome-derived ncRNAs play an important role in tumor angiogenesis. In this review, we briefly outline the characteristics of exosomes, ncRNAs, and tumor angiogenesis. Then, the mechanism of the impact of exosome-derived ncRNAs on tumor angiogenesis is analyzed from various angles. In addition, we focus on the regulatory role of exosome-derived ncRNAs in angiogenesis in different types of cancer. Furthermore, we emphasize the potential role of exosome-derived ncRNAs as biomarkers in cancer diagnosis and prognosis and therapeutic targets in the treatment of tumors.

Application of engineered extracellular vesicles for targeted tumor therapy

All cells, including prokaryotes and eukaryotes, could release extracellular vesicles (EVs). EVs contain many cellular components, including RNA, and surface proteins, and are essential for maintaining normal intercellular communication and homeostasis of the internal environment. EVs released from different tissues and cells exhibit excellent properties and functions (e.g., targeting specificity, regulatory ability, physical durability, and immunogenicity), rendering them a potential new option for drug delivery and precision therapy. EVs have been demonstrated to transport antitumor drugs for tumor therapy; additionally, EVs' contents and surface substance can be altered to improve their therapeutic efficacy in the clinic by boosting targeting potential and drug delivery effectiveness. EVs can regulate immune system function by affecting the tumor microenvironment, thereby inhibiting tumor progression. Co-delivery systems for EVs can be utilized to further improve the drug delivery efficiency of EVs, including hydrogels and liposomes. In this review, we discuss the isolation technologies of EVs, as well as engineering approaches to their modification. Moreover, we evaluate the therapeutic potential of EVs in tumors, including engineered extracellular vesicles and EVs' co-delivery systems.

Technologies such as microfluidics can improve EVs isolation efficiency.

Engineering technologies can improve EVs drug loading efficiency and tumor targeting.

EVs-based drug co-delivery systems are being developed, such as those with liposomes and hydrogels.

Extracellular Vesicles from Esophageal Squamous Cell Carcinoma Promote Angiogenesis and Tumor Growth

Angiogenesis is a prerequisite for tumor development and metastasis. Emerging evidence shows that tumor-derived extracellular vesicles (EVs) are an important component of tumor microenvironment, which participate in the communication between normal cells and tumor cells. In this study, we aimed to investigate the role of EVs derived from esophageal squamous cell carcinoma (ESCC) on tumor angiogenesis. We found that ESCC cell-derived EVs promoted the proliferation, migration, and tubule formation of human umbilical vein endothelial cells in vitro, and enhanced angiogenesis and tumor growth in vivo. Our results suggest that ESCC cell-derived EVs could promote angio-genesis and tumor growth, which also indicated the application of EVs as a valuable therapeutic strategy of ESCC.

Tumor-derived extracellular vesicles inhibit HGF/c-Met and EGF/EGFR pathways to accelerate the radiosensitivity of nasopharyngeal carcinoma cells via microRNA-142-5p delivery

Radioresistance prevails as one of the largest obstacles in the clinical treatment of nasopharyngeal carcinoma (NPC). Meanwhile, tumor-derived extracellular vesicles (TEVs) possess the ability to manipulate radioresistance in NPC. However, its mechanism remains to be further explored. Therefore, the current study set out to explore the mechanism of microRNA (miR)-142-5p delivered by TEVs in regard to the radiosensitivity of NPC. Firstly, peripheral blood samples were collected from patients with radioresistance and radiosensitivity, followed by RT-qPCR detection of miR-142-5p expression. A dual-luciferase reporter assay was carried out to elucidate the targeting relationship of miR-142-5p with HGF and EGF. In addition, radiotherapy-resistant NPC cell models were established by screening NPC cells with gradient increasing radiation exposure, and co-incubated with EVs isolated from miR-142-5p mimic-transfected NPC cells, followed by overexpression of HGF and EGF. Moreover, cell viability was detected by means of MTS, cell proliferation with a colony formation assay, cell apoptosis with flow cytometry, and expression patterns of related genes with the help of Western blot analysis. NPC xenotransplantation models in nude mice were also established by subcutaneous injection of 5-8FR cells to determine apoptosis, tumorigenicity, and radiosensitivity in nude mice. It was found that miR-142-5p was poorly expressed in peripheral blood from NPC patients with radioresistance. Mechanistic experimentation illustrated that miR-142-5p inversely targeted HGF and EGF to inactivate the HGF/c-Met and EGF/EGFR pathways, respectively. NPC cell apoptosis was observed to be augmented, while their radioresistance and proliferation were restricted by EVs-miR-142-5p or HGF silencing, or EGF silencing. Furthermore, EVs-miR-142-5p inhibited growth and radioresistance and accelerated the apoptosis of radiotherapy-resistant NPC cells in nude mice by inhibiting the HGF/c-Met and EGF/EGFR pathways. Collectively, our findings indicated that TEVs might inhibit the HGF/c-Met and EGF/EGFR pathways by delivering miR-142-5p into radiotherapy-resistant NPC cells to enhance radiosensitivity in NPC.

Circulating exosomal miRNAs and cancer early diagnosis

Microribonucleic acids (miRNAs) are small non-coding ribonucleic acids (ncRNAs), which can affect recognition of homologous sequences and interfere with transcription. It plays key roles in the initiation, development, resistance, metastasis or recurrence of cancers. Identifying circulatory indicators will positively improve the prognosis and quality of life of patients with early cancer. Previous studies have shown that miRNA is highly involved in cancer. In addition, miRNA derived from cancers can be encapsulated as exosomes and further extracted into circulatory systems to realize malignant functions. It indicates that circulating exosome-derived miRNAs have the potential to replace conventional biomarkers as cancer derived exosomes carrying miRNAs can be identified by specific markers and might be more stable and accurate for early diagnosis.

The Sex-Related Interplay between TME and Cancer: On the Critical Role of Estrogen, MicroRNAs and Autophagy

The interplay between cancer cells and the tumor microenvironment (TME) has a fundamental role in tumor progression and response to therapy. The plethora of components constituting the TME, such as stroma, fibroblasts, endothelial and immune cells, as well as macromolecules, e.g., hormones and cytokines, and epigenetic factors, such as microRNAs, can modulate the survival or death of cancer cells. Actually, the TME can stimulate the genetically regulated programs that the cell puts in place under stress: apoptosis or, of interest here, autophagy. However, the implication of autophagy in tumor growth appears still undefined. Autophagy mainly represents a cyto-protective mechanism that allows cell survival but, in certain circumstances, also leads to the blocking of cell cycle progression, possibly leading to cell death. Since significant sex/gender differences in the incidence, progression and response to cancer therapy have been widely described in the literature, in this review, we analyzed the roles played by key components of the TME, e.g., estrogen and microRNAs, on autophagy regulation from a sex/gender-based perspective. We focused our attention on four paradigmatic and different forms of cancers-colon cancer, melanoma, lymphoma, and lung cancer-concluding that sex-specific differences may exert a significant impact on TME/cancer interaction and, thus, tumor growth.

Exosomes in the lung cancer microenvironment: biological functions and potential use as clinical biomarkers

Lung cancer is one of the most common malignant tumours worldwide. however, emerging immunotherapy and targeted therapies continue to show limited efficacy. In the search for new targets for lung cancer treatment, exosomes have become a major focus of research. Exosomes play an important role in the tumour microenvironment (TME) of lung cancer and affect invasion, metastasis, and treatment responses. This review describes our current understanding of the release of exosomes derived from different cells in the TME, the effects of exosomes on T/Tregs, myeloid-derived suppressor cells, tumour-associated macrophages, dendritic cells, and natural killer cells, and the role of exosomes in the endothelial–mesenchymal transition, angiogenesis, and cancer-associated fibroblasts. In particular, this review focuses on the potential clinical applications of exosomes in the lung cancer microenvironment and their prognostic and diagnostic value.

Biomarkers for Diagnosis, Prognosis and Response to Immunotherapy in Melanoma

Simple Summary

Cutaneous Melanoma is a form of skin cancer characterized by an elevated mutational load that favors high spread to distant organs and resistance to therapies. The identification of biomarkers, able to dissect normal and pathogenic biological processes and response to therapeutic intervention, is necessary to describe melanoma as accurately as possible, having a positive impact on early diagnosis, in turn selecting the best therapeutic option. Recently, a great number of new biomarkers were evaluated, in order to identify those patients who may have clinical benefit from a therapeutic choice, particularly for immunotherapy. At present, these new biomarkers wait to be validated before clinical use. Hence, the requirement to look at and periodically update the advances in this field.

Abstract

Cutaneous Melanoma classification is constantly looking for specific and sensitive biomarkers capable of having a positive effect on diagnosis, prognosis and risk assessment, eventually affecting clinical outcome. Classical morphological, immunohistochemical and the well-known BRAF and NRAS genetic biomarkers do not allow the correct categorization of patients, being melanoma conditioned by high genetic heterogeneity. At the same time, classic prognostic methods are unsatisfactory. Therefore, new advances in omics and high-throughput analytical techniques have enabled the identification of numerous possible biomarkers, but their potentiality needs to be validated and standardized in prospective studies. Melanoma is considered an immunogenic tumor, being the first form of cancer to take advantage of the clinical use of the immune-checkpoint blockers. However, as immunotherapy is effective only in a limited number of patients, biomarkers associated with different responses are essential to select the more promising therapeutic approach and maximize clinical benefits. In this review, we summarize the most utilized biomarkers for Cutaneous Melanoma diagnosis, focusing on new prognostic and predictive biomarkers mainly associated with immunotherapy.

Mycosis fungoides-derived exosomes promote cell motility and are enriched with microRNA-155 and microRNA-1246, and their plasma-cell-free expression may serve as a potential biomarker for disease burden

BACKGROUND

Literature regarding exosomes as mediators in intercellular communication to promote progression in mycosis fungoides (MF) is lacking.

OBJECTIVES

To characterize MF-derived exosomes and their involvement in the disease.

METHODS

Exosomes were isolated by ultracentrifugation from cutaneous T-cell lymphoma (CTCL) cell lines, and from plasma of patients with MF and controls (healthy individuals). Exosomes were confirmed by electron microscopy, NanoSight and CD81 staining. Cell-line exosomes were profiled for microRNA array. Exosomal microRNA (exomiRNA) expression and uptake, and plasma-cell-free microRNA (cfmiRNA) were analysed by reverse-transcriptase quantitative polymerase chain reaction. Exosome uptake was monitored by fluorescent labelling and CD81 immunostaining. Migration was analysed by transwell migration assay.

RESULTS

MyLa- and MJ-derived exosomes had a distinctive microRNA signature with abundant microRNA (miR)-155 and miR-1246. Both microRNAs were delivered into target cells, but only exomiR-155 was tested, demonstrating a migratory effect on target cells. Plasma levels of cfmiR-1246 were significantly highest in combined plaque/tumour MF, followed by patch MF, and were lowest in controls (plaque/tumour > patch > healthy), while cfmiR-155 was upregulated only in plaque/tumour MF vs. controls. Specifically, exomiR-1246 (and not exomiR-155) was higher in plasma of plaque/tumour MF than in healthy controls. Plasma exosomes from MF but not from controls increased cell migration.

CONCLUSIONS

Our findings show that MF-derived exosomes promote cell motility and are enriched with miR-155, a well-known microRNA in MF, and miR-1246, not previously reported in MF. Based on their plasma expression we suggest that they may serve as potential biomarkers for tumour burden.

Non-Coding RNAs in the Transcriptional Network That Differentiates Skeletal Muscles of Sedentary from Long-Term Endurance- and Resistance-Trained Elderly

In a previous study, the whole transcriptome of the vastus lateralis muscle from sedentary elderly and from age-matched athletes with an exceptional record of high-intensity, life-long exercise training was compared-the two groups representing the two extremes on a physical activity scale. Exercise training enabled the skeletal muscle to counteract age-related sarcopenia by inducing a wide range of adaptations, sustained by the expression of protein-coding genes involved in energy handling, proteostasis, cytoskeletal organization, inflammation control, and cellular senescence. Building on the previous study, we examined here the network of non-coding RNAs participating in the orchestration of gene expression and identified differentially expressed micro- and long-non-coding RNAs and some of their possible targets and roles. Unsupervised hierarchical clustering analyses of all non-coding RNAs were able to discriminate between sedentary and trained individuals, regardless of the exercise typology. Validated targets of differentially expressed miRNA were grouped by KEGG analysis, which pointed to functional areas involved in cell cycle, cytoskeletal control, longevity, and many signaling pathways, including AMP-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR), which had been shown to be pivotal in the modulation of the effects of high-intensity, life-long exercise training. The analysis of differentially expressed long-non-coding RNAs identified transcriptional networks, involving lncRNAs, miRNAs and mRNAs, affecting processes in line with the beneficial role of exercise training.

Exosome-mediated Hic-5 regulates proliferation and apoptosis of osteosarcoma via Wnt/β-catenin signal pathway

The expression of Hic-5 was detected in osteosarcoma patients and osteosarcoma cell lines by RT-PCR. Then RFP-sh-Hic-5 was transfected into osteosarcoma cell lines. The effect of Hic-5 on cell viability, proliferation and apoptosis were assessed by MTT, EdU kit and Flow cytometry. The exosomes were isolated from MG-63 cell supernatant by an Exosome Isolation Kit. The exosome-Hic-5 was confirmed by transmission electron microscope, particle size detection and RT-PCR. Next, exosome-Hic-5 treated cells were explored the cell viability, proliferation and apoptosis. Further, Co-IP assay was employed for identifying the relationship between Hic-5 and smad4. TCF/LEF and the protein level of components of wnt/β-catenin signals were detected by TOP luciferase assay and western blot. Hic-5 was upregulated in osteosarcoma tissues and cell. Forced decreased expression Hic-5 inhibited the proliferation of osteosarcoma cell lines, and induced apoptosis of MG-63 and HOS. In vivo, silencing Hic-5 remitted the tumor progression. Further, we isolated the exosomes from MG-63 supernatant, exosomes concluding Hic-5 would regulated the proliferation and apoptosis level of MG-63 and HOS cells. Further, Hic-5 interacted with smad4 and regulated Wnt/β-catenin signal by decreasing TCF/LEF activity. Silencing Hic-5 inhibited the proliferation and induced apoptosis of osteosarcoma cell via inactivating Wnt/β-catenin signal by exosome pathway.

Exosomes and Extracellular Vesicles as Emerging Theranostic Platforms in Cancer Research

Exosomes are endosome-derived nanovesicles produced by healthy as well as diseased cells. Their proteic, lipidic and nucleic acid composition is related to the cell of origin, and by vehiculating bioactive molecules they are involved in cell-to-cell signaling, both in healthy and pathologic conditions. Being nano-sized, non-toxic, biocompatible, scarcely immunogenic, and possessing targeting ability and organotropism, exosomes have been proposed as nanocarriers for their potential application in diagnosis and therapy. Among the different techniques exploited for exosome isolation, the sequential ultracentrifugation/ultrafiltration method seems to be the gold standard; alternatively, commercially available kits for exosome selective precipitation from cell culture media are frequently employed. To load a drug or a detectable agent into exosomes, endogenous or exogenous loading approaches have been developed, while surface engineering procedures, such as click chemistry, hydrophobic insertion and exosome display technology, allow for obtaining actively targeted exosomes. This review reports on diagnostic or theranostic platforms based on exosomes or exosome-mimetic vesicles, highlighting the diverse preparation, loading and surface modification methods applied, and the results achieved so far.

The potential roles of exosomal noncoding RNAs in osteosarcoma

Clinically, it is difficult to efficaciously screen and diagnose osteosarcoma (OS) in advance due to the low sensitivity and poor specificity of the existing tumor markers. Exosomes (Exos) are nanoscale vesicles containing RNAs, lipids, and proteins with a diameter of 30-100 nm. They are multivesicular bodies formed during the invagination of lysosomal particles in cells and released extracellularly after fusing with cell membranes. Besides, Exos are important carriers of cell-to-cell communication signals and genetic materials in the tumor microenvironment. During tumorigenesis, the tumor cells interplay with immune cells, endothelial cells, and related fibroblasts through Exos and boost cancer development. After altering the surrounding microenvironment, the Exos drive tumor cells to proliferate, speed up angiogenesis, and boost cancers to develop along with body fluid transportation. Currently, Exos are becoming novel noninvasive tumor diagnostic markers with high sensitivity, exerting pivotal impacts in fundamental research and clinical applications. Here, we review the existing literature on the roles of exosomal noncoding RNAs in OS progression and their potential clinical applications as novel biomarkers and therapeutics.

Exosome-mediated miR-9-5p promotes proliferation and migration of renal cancer cells both in vitro and in vivo by targeting SOCS4

Exosomes secreted by cancer cells play important roles in tumor progression by interacting with cell receptors. Renal cancer derived exosomes contain miRNAs which are associated with cell proliferation and invasion. Micro RNA 9-5 (miR-9-5) is highly expressed in the serum of renal cancer patients with advanced (tumor size - node - metastasis) TNM stage and Fuhrman grade. miR-9-5p is extensively expressed in exosomes derived from renal cancer cells. Overexpression of miR-9-5p promotes proliferation and invasion of A-704 (a cancer cell line of human kidney) cells via targeting and deregulating SOCS4 mRNA. Inhibition of the Janus kinase (JAK)/signaling transducer and activator of transcription (STAT) pathway by SOCS4 will be reduced, which leads to phosphorylation of STAT3 and JAK. Activated cytokine signaling promotes cell proliferation and invasion, and inhibits apoptosis. Moreover, overexpression of SOCS4 reduces miR-9-5p levels and plays an opposite role in cell. To conclude, exosomal miR-9-5p plays important roles in renal cancer both in vivo and in vitro, indicating it may be used as biomarker for diagnosis and for monitoring the efficacy if therapy.

Sex and Gender Disparities in Melanoma

Worldwide, the total incidence of cutaneous melanoma is higher in men than in women, with some differences related to ethnicity and age and, above all, sex and gender. Differences exist in respect to the anatomic localization of melanoma, in that it is more frequent on the trunk in men and on the lower limbs in women. A debated issue is if-and to what extent-melanoma development can be attributed to gender-specific behaviors or to biologically intrinsic differences. In the search for factors responsible for the divergences, a pivotal role of sex hormones has been observed, although conflicting results indicate the involvement of other mechanisms. The presence on the X chromosome of numerous miRNAs and coding genes playing immunological roles represents another important factor, whose relevance can be even increased by the incomplete X chromosome random inactivation. Considering the known advantages of the female immune system, a different cancer immune surveillance efficacy was suggested to explain some sex disparities. Indeed, the complexity of this picture emerged when the recently developed immunotherapies unexpectedly showed better improvements in men than in women. Altogether, these data support the necessity of further studies, which consider enrolling a balanced number of men and women in clinical trials to better understand the differences and obtain actual gender-equitable healthcare.

Exosomal miRNAs in tumor microenvironment

Tumor microenvironment (TME) is the internal environment in which tumor cells survive, consisting of tumor cells, fibroblasts, endothelial cells, and immune cells, as well as non-cellular components, such as exosomes and cytokines. Exosomes are tiny extracellular vesicles (40-160nm) containing active substances, such as proteins, lipids and nucleic acids. Exosomes carry biologically active miRNAs to shuttle between tumor cells and TME, thereby affecting tumor development. Tumor-derived exosomal miRNAs induce matrix reprogramming in TME, creating a microenvironment that is conducive to tumor growth, metastasis, immune escape and chemotherapy resistance. In this review, we updated the role of exosomal miRNAs in the process of TME reshaping.