Exosomal microRNA-205 is involved in proliferation, migration, invasion, and apoptosis of ovarian cancer cells via regulating VEGFA

Clinical relevance of exosome-derived microRNAs in Ovarian Cancer: Looking for new tumor biological fingerprints

Specific tumor-derived extracellular vesicles, called exosomes, are considered as potential key players in cross-talk between immune system and tumor microenvironment in several solid tumors. Different studies highlighted the clinical relevance of exosomes in ovarian cancer (OC) for their role in early diagnosis, prognosis, chemoresistance, targeted therapy. The exosomes are nanosize vesicles carrying lipids, proteins, and nucleic acids. In particular, exosomes shuttle a wide spectrum of microRNAs (miRNAs) able to induce phenotypic reprogramming of target cells, contributing to tumor progression. In this review, we will discuss the promising role of miRNAs shuttled by exosomes, called exosomal miRNAs (exo-miRNAs), as potential biomarkers for early detection, tumour progression and metastasis, prognosis, and response to therapy in OC women, in order to search for new potential biological fingerprints able to better characterize the evolution of this malignancy and provide a clinically relevant non-invasive approach useful for adopting, in future, personalized therapeutic strategies.

Exosomal Cargo in Ovarian Cancer Dissemination

Ovarian cancer (OC) has the highest mortality rate among all gynecologic cancers and is characterized by early peritoneal spread. The growth and development of OC are associated with the formation of ascitic fluid, creating a unique tumor microenvironment. Understanding the mechanisms of tumor progression is crucial in identifying new diagnostic biomarkers and developing novel therapeutic strategies. Exosomes, lipid bilayer vesicles measuring 30-150 nm in size, are known to establish a crucial link between malignant cells and their microenvironment. Additionally, the confirmed involvement of exosomes in carcinogenesis enables them to mediate the invasion, migration, metastasis, and angiogenesis of tumor cells. Functionally active non-coding RNAs (such as microRNAs, long non-coding RNAs, circRNAs), proteins, and lipid rafts transported within exosomes can activate numerous signaling pathways and modify gene expression. This review aims to expand our understanding of the role of exosomes and their contents in OC carcinogenesis processes such as epithelial-mesenchymal transition (EMT), angiogenesis, vasculogenic mimicry, tumor cell proliferation, and peritoneal spread. It also discusses the potential for utilizing exosomal cargo to develop novel "liquid biopsy" biomarkers for early OC diagnosis.

Emerging Applications of Liquid Biopsies in Ovarian Cancer

Liquid biopsy is a new diagnostic tool in precision oncology that can be used as a complementary or alternative method to surgical biopsies. It is a cutting-edge sampling technique that examines distinct cancer components, such as exosomes and circulating tumor cells discharged into the peripheral circulation, to identify tumor biomarkers through various methods, including polymerase chain reaction (PCR). Liquid biopsy has several benefits, including its non-invasiveness and practicality, which permit serial sampling and long-term monitoring of dynamic tumor changes. Ovarian cancer (OC), the most lethal gynecologic malignancy in the world, is typically diagnosed at stages II and III, which makes recovery and treatment extremely difficult. Relapsed OC and chemotherapy resistance of ovarian tumor cells are other clinical challenges. Although liquid biopsy is not a routinely used diagnostic test, it should be utilized in the diagnosis and prognosis of OC for early detection and treatment. It is less intrusive than conventional tissue biopsies, allowing for the continuous collection of serial blood samples to track cancer development in real time. Before therapeutic application, more investigation is required to pinpoint the particular release processes, the source tissue, and the biological significance of the bulk of liquid biopsy contents.

The role of extracellular vesicles in circulating tumor cell-mediated distant metastasis

Current research has demonstrated that extracellular vesicles (EVs) and circulating tumor cells (CTCs) are very closely related in the process of distant tumor metastasis. Primary tumors are shed and released into the bloodstream to form CTCs that are referred to as seeds to colonize and grow in soil-like distant target organs, while EVs of tumor and nontumor origin act as fertilizers in the process of tumor metastasis. There is no previous text that provides a comprehensive review of the role of EVs on CTCs during tumor metastasis. In this paper, we reviewed the mechanisms of EVs on CTCs during tumor metastasis, including the ability of EVs to enhance the shedding of CTCs, protect CTCs in circulation and determine the direction of CTC metastasis, thus affecting the distant metastasis of tumors.

Knockdown of Simulated-Solar-Radiation-Sensitive miR-205-5p Does Not Induce Progression of Cutaneous Squamous Cell Carcinoma In Vitro

Solar radiation is the main risk factor for cSCC development, yet it is unclear whether the progression of cSCC is promoted by solar radiation in the same way as initial tumorigenesis. Additionally, the role of miRNAs, which exert crucial functions in various tumors, needs to be further elucidated in the context of cSCC progression and connection to solar radiation. Thus, we chronically irradiated five cSCC cell lines (Met-1, Met-4, SCC-12, SCC-13, SCL-II) with a custom-built irradiation device mimicking the solar spectrum (UVB, UVA, visible light (VIS), and near-infrared (IRA)). Subsequently, miRNA expression of 51 cancer-associated miRNAs was scrutinized using a flow cytometric multiplex quantification assay (FirePlex®, Abcam). In total, nine miRNAs were differentially expressed in cell-type-specific as well as universal manners. miR-205-5p was the only miRNA downregulated after SSR-irradiation in agreement with previously gathered data in tissue samples. However, inhibition of miR-205-5p with an antagomir did not affect cell cycle, cell growth, apoptosis, or migration in vitro despite transient upregulation of oncogenic target genes after miR-205-5p knockdown. These results render miR-205-5p an unlikely intracellular effector in cSCC progression. Thus, effects on intercellular communication in cSCC or the simultaneous examination of complementary miRNA sets should be investigated.

Microfluidic platforms in diagnostic of ovarian cancer

The most important reason for death from ovarian cancer is the late diagnosis of this disease. The standard treatment of ovarian cancer includes surgery and chemotherapy based on platinum, which is associated with side effects for the body. Due to the nonspecific nature of clinical symptoms, developing a platform for early detection of this disease is needed. In recent decades, the advancements of microfluidic devices and systems have provided several advantages for diagnosing ovarian cancer. Designing and manufacturing new platforms using specialized technologies can be a big step toward improving the prevention, diagnosis, and treatment of this group of diseases. Organ-on-a-chip microfluidic devices are increasingly used as a promising platform in cancer research, with a focus on specific biological aspects of the disease. This review focusing on ovarian cancer and microfluidic application technologies in its diagnosis. Additionally, it discusses microfluidic platforms and their potential future perspectives in advancing ovarian cancer diagnosis.

Liquid biopsy in ovarian cancer: advantages and limitations for prognosis and diagnosis

Ovarian cancer (OC) is a highly fatal gynecologic malignancy, often diagnosed at an advanced stage which presents significant challenges for disease management. The clinical application of conventional tissue biopsy methods and serological biomarkers has limitations for the diagnosis and prognosis of OC patients. Liquid biopsy is a novel sampling method that involves analyzing distinctive tumor elements secreted into the peripheral blood. Growing evidence suggests that liquid biopsy methods such as circulating tumor cells, cell-free RNA, circulating tumor DNA, exosomes, and tumor-educated platelets may improve early prognosis and diagnosis of OC, leading to enhanced therapeutic management of the disease. This study reviewed the evidence demonstrating the utility of liquid biopsy components in OC prognosis and diagnosis, and evaluated the current advantages and limitations of these methods. Additionally, the existing obstacles and crucial topics for future studies utilizing liquid biopsy in OC patients were discussed.

BCL10 correlates with bad prognosis and immune infiltration of tumor microenvironment in hepatocellular carcinoma

It has been reported that B-cell CLL-lymphoma 10 (BCL10) serves as an oncogene in cervical cancer. However, the roles of BCL10 in hepatocellular carcinoma (HCC), especially involved in immune infiltration remain not clear. This study aims to explore the relationship between BCL10 and the prognosis and clinical significance, and immune infiltration in HCC. The expression of BCL10 was analyzed between HCC samples and non-tumor samples in the multiple datasets. In addition, the prognostic values of BCL10 and its methylation in HCC were also investigated. The clinical significance of BCL10 has also been explored. Furthermore, the correlation between BCL10 and immune infiltration in HCC microenvironment was assessed. Finally, the biological behaviors of BCL10 in HCC were verified by cell function experiments. It was found that the expression levels of BCL10 were increased in HCC patients in multiple datasets. Moreover, the increased BCL10 and its reduced methylation were associated with the poor survival. BCL10 was significantly associated with immune infiltration. When BCL10 was knocked down in HCC cells, their proliferation ability was significantly inhibited, their migration was significantly decreased, their apoptosis was significantly increased, and AKT signaling pathway was inhibited. In conclusion, BCL10 is a potential prognostic and diagnostic biomarker related to immune infiltration in HCC microenvironment.

Research progress on anti-ovarian cancer mechanism of miRNA regulating tumor microenvironment

Ovarian cancer is the most deadly malignancy among women, but its complex pathogenesis is unknown. Most patients with ovarian cancer have a poor prognosis due to high recurrence rates and chemotherapy resistance as well as the lack of effective early diagnostic methods. The tumor microenvironment mainly includes extracellular matrix, CAFs, tumor angiogenesis and immune-associated cells. The interaction between tumor cells and TME plays a key role in tumorigenesis, progression, metastasis and treatment, affecting tumor progression. Therefore, it is significant to find new tumor biomarkers and therapeutic targets. MicroRNAs are non-coding RNAs that post-transcriptionally regulate the expression of target genes and affect a variety of biological processes. Studies have shown that miRNAs regulate tumor development by affecting TME. In this review, we summarize the mechanisms by which miRNAs affect ovarian cancer by regulating TME and highlight the key role of miRNAs in TME, which provides new targets and theoretical basis for ovarian cancer treatment.

Extracellular vesicle contents as non-invasive biomarkers in ovarian malignancies

Ovarian cancer most commonly presents at an advanced stage where survival is approximately 30% compared with >80% if diagnosed and treated before disease spreads. Diagnostic capabilities have progressed from surgical staging via laparotomy to image-guided biopsies and immunohistochemistry staining, along with advances in technology and medicine. Despite improvements in diagnostic capabilities, population-level screening for ovarian cancer is not recommended. Extracellular vesicles (EVs) are 40–150 nm structures formed when the cellular lipid bilayer invaginates. These structures function in cell signaling, immune responses, cancer progression, and establishing the tumor microenvironment. EVs are found in nearly every bodily fluid, including serum, plasma, ascites, urine, and effusion fluid, and contain molecular cargo from their cell of origin. This cargo can be analyzed to yield information about a possible malignancy. In this review we describe how the cargo of EVs has been studied as biomarkers in ovarian cancer. We bring together studies analyzing evidence for various cargos as ovarian cancer biomarkers. Then, we describe the role of EVs in modulation of the tumor microenvironment. This review also summarizes the therapeutic and translational potential of EVs for their optimal utilization as non-invasive biomarkers for novel treatments against cancer.

Cancer-Secreted Exosomal MiR-620 Inhibits ESCC Aerobic Glycolysis via FOXM1/HER2 Pathway and Promotes Metastasis

Background

Esophageal squamous cell carcinoma (ESCC) is a leading cause of cancer death worldwide. MicroRNAs (MiRNAs) have been reported to regulate cell functions through exosomes. Through the Gene Expression Omnibus (GEO) database, miR-620 was selected as a serum miRNA highly expressed in ESCC, but its detailed role in ESCC has not been explored. Tumor-secreted miRNAs have been reported to promote cancer metastasis through reprogramming the aerobic glycolysis of lung fibroblasts. Therefore, we intended to verify whether exosomal miR-620 secreted in ESCC cells may regulate the aerobic glycolysis of lung fibroblasts.

Methods

The effect of miR-620 on the aerobic glycolysis of ESCC cells was firstly verified through bioinformatics prediction and mechanism assays. Exosomes secreted from ESCC cells was detected, and the influence of exosomal miR-620 in regulating the aerobic glycolysis of lung fibroblasts was then verified both in vitro and in vivo.

Results

MiR-620 inhibited ESCC malignancy and suppressed the aerobic glycolysis of ESCC cells via targeting Forkhead box M1 (FOXM1) and human epidermal growth factor receptor 2 (HER2). Moreover, exosomal miR-620 was highly secreted in ESCC and could regulate HFL1 aerobic glycolysis via FOXM1/HER2 signaling. Furthermore, exosomal miR-620 could promote ESCC metastasis by reprogramming the aerobic glycolysis of lung fibroblasts (HFL1).

Conclusion

Exosomal miR-620 secreted by ESCC cells inhibited the aerobic glycolysis via FOXM1/HER2 axis and promoted cancer metastasis.

Potential clinical utility of liquid biopsies in ovarian cancer

Ovarian cancer (OC) is the most lethal gynecologic malignancy worldwide. One of the main challenges in the management of OC is the late clinical presentation of disease that results in poor survival. Conventional tissue biopsy methods and serological biomarkers such as CA-125 have limited clinical applications. Liquid biopsy is a novel sampling method that analyzes distinctive tumour components released into the peripheral circulation, including circulating tumour DNA (ctDNA), circulating tumour cells (CTCs), cell-free RNA (cfRNA), tumour-educated platelets (TEPs) and exosomes. Increasing evidence suggests that liquid biopsy could enhance the clinical management of OC by improving early diagnosis, predicting prognosis, detecting recurrence, and monitoring response to treatment. Capturing the unique tumour genetic landscape can also guide treatment decisions and the selection of appropriate targeted therapies. Key advantages of liquid biopsy include its non-invasive nature and feasibility, which allow for serial sampling and longitudinal monitoring of dynamic tumour changes over time. In this review, we outline the evidence for the clinical utility of each liquid biopsy component and review the advantages and current limitations of applying liquid biopsy in managing ovarian cancer. We also highlight future directions considering the current challenges and explore areas where more studies are warranted to elucidate its emerging clinical potential.

Extracellular vesicles in ovarian cancer chemoresistance, metastasis, and immune evasion

Chemoresistance and metastasis are the major challenges for the current ovarian cancer treatment. Understanding the mechanisms of ovarian cancer progression and metastasis is critically important for developing novel therapies. The advances in extracellular vesicles (EVs) research in recent years have attracted extensive attention. EVs contain a variety of proteins, RNAs, DNAs, and metabolites. Accumulating evidence indicates that ovarian cancer cells secrete a large amount of EVs, playing an important role in tumor progression and recurrence. In the microenvironment of ovarian tumor, EVs participate in the information transmission between stromal cells and immune cells, promoting the immune escape of ovarian cancer cells and facilitating cancer metastasis. Here, we review the recent advances of EVs in chemoresistance, mechanisms of metastasis, and immune evasion of ovarian cancer. Furthermore, we also discuss the challenges of EV research and future application of EVs as promising biomarker sources in response to therapy and in therapy-delivery approaches for ovarian cancer patients.

Exosome-mediated lncRNA SNHG11 regulates angiogenesis in pancreatic carcinoma through miR-324-3p/VEGFA axis

Pancreatic carcinoma (PC) is one of the most common and deadly human malignancies worldwide. LncRNAs play significant roles in the occurrence and development of various cancers. LncRNA SNHG11 (SNHG11) has been found to display high expression in serum of PC patients, which implies that dysregulated SNHG11 may be related to the development of PC. However, there is still a knowledge gap concerning the specific function and molecular mechanism of SNHG11 in PC. After conducting experiments with constructed models in vitro or in vivo, we found that exosomal SNHG11 promoted cell proliferation, migration, and angiogenesis but impeded cell apoptosis in PC in vitro, and additionally, it facilitated tumor growth in vivo. Exosome-mediated SNHG11 regulated the expression of VEGFA through sponging miR-324-3p. Rescue assays validated that the inhibitory effect of SNHG11 depletion on cell proliferation, migration, and angiogenesis could be reversed by miR-324-3p downregulation or VEGFA upregulation, and the promoting effect of SNHG11 silence on cell apoptosis could be rescued by transfection of miR-324-3p inhibitor or pcDNA3.1-VEGFA. To conclude, exosomal-mediated SNHG11 could regulate PC progression via miR-324-3p/VEGFA axis. Our findings may provide a novel insight for understanding PC, which might contribute to the development of potential PC biomarker.

Exosome miR-23a-3p From Osteoblast Alleviates Spinal Cord Ischemia/Reperfusion Injury by Down-regulating KLF3-activated CCNL2 Transcription

BACKGROUND

Spinal cord ischemia/reperfusion injury (SCIRI) is usually caused by spinal surgery or aortic aneurysm surgery and can eventually lead to paralysis or paraplegia and neurological dysfunction. Exosomes are considered as one of the most promising therapeutic strategies for SCIRI as they can pass the blood-spinal barrier. Previous studies have proved that exosomes secreted by osteocytes have a certain slowing effect on SCIRI.

AIM

We aimed to explore the effect of osteoblast secreted exosomes on SCIRI.

METHODS

Firstly, neurons and osteoblasts were co-cultured under different conditions. GEO database was utilized to detect the expression of miR-23a-3p in osteoblast exosomes. SCIRI cells were treated with exosomes, and the detection was taken to prove whether miR-23a-3p could slow the progression of SCIRI. Downstream gene and the potential regulatory mechanism were explored through database and functional experiments.

RESULTS

MiR-23a-3p was highly expressed in exosomes and it slowed down the process of SCIRI. Downstream mRNA KLF3 could bind to miR-23a-3p and was highly expressed in IRI. Moreover, CCNL2 was regulated by KLF3 and was highly expressed in IRI. Rescue experiments verified that miR-23a-3p suppressed the transcription of CCNL2 by targeting KLF3.

CONCLUSION

Exosome miR-23a-3p from osteoblast alleviates SCIRI by down-regulating KLF3-activated CCNL2 transcription.

MicroRNAs as Biomarkers for Early Diagnosis, Prognosis, and Therapeutic Targeting of Ovarian Cancer

Ovarian cancer is the major cause of gynecologic cancer-related mortality. Regardless of outstanding advances, which have been made for improving the prognosis, diagnosis, and treatment of ovarian cancer, the majority of the patients will die of the disease. Late-stage diagnosis and the occurrence of recurrent cancer after treatment are the most important causes of the high mortality rate observed in ovarian cancer patients. Unraveling the molecular mechanisms involved in the pathogenesis of ovarian cancer may help find new biomarkers and therapeutic targets for ovarian cancer. MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression, mostly at the posttranscriptional stage, through binding to mRNA targets and inducing translational repression or degradation of target via the RNA-induced silencing complex. Over the last two decades, the role of miRNAs in the pathogenesis of various human cancers, including ovarian cancer, has been documented in multiple studies. Consequently, these small RNAs could be considered as reliable markers for prognosis and early diagnosis. Furthermore, given the function of miRNAs in various cellular pathways, including cell survival and differentiation, targeting miRNAs could be an interesting approach for the treatment of human cancers. Here, we review our current understanding of the most updated role of the important dysregulation of miRNAs and their roles in the progression and metastasis of ovarian cancer. Furthermore, we meticulously discuss the significance of miRNAs as prognostic and diagnostic markers. Lastly, we mention the opportunities and the efforts made for targeting ovarian cancer through inhibition and/or stimulation of the miRNAs.

The functions and potential roles of extracellular vesicle noncoding RNAs in gynecological malignancies

Extracellular vesicles (EVs) are small membranous vesicles secreted by multiple kinds of cells and are widely present in human body fluids. EVs containing various constituents can transfer functional molecules from donor cells to recipient cells, thereby mediating intercellular communication. Noncoding RNAs (ncRNAs) are a type of RNA transcript with limited protein-coding capacity, that have been confirmed to be enriched in EVs in recent years. EV ncRNAs have become a hot topic because of their crucial regulating effect in disease progression, especially in cancer development. In this review, we summarized the biological functions of EV ncRNAs in the occurrence and progression of gynecological malignancies. In addition, we reviewed their potential applications in the diagnosis and treatment of gynecological malignancies.

circ_C20orf11 enhances DDP resistance by inhibiting miR-527/YWHAZ through the promotion of extracellular vesicle-mediated macrophage M2 polarization in ovarian cancer

Ovarian cancer is a fatal gynecologic tumor, and conventional treatment is mainly limited by chemoresistance. The mechanism contributing to chemoresistance in ovarian cancer has yet to be established. This study aimed to investigate the specific role of circ_C20orf11 in regulating chemoresistance to cisplatin (DDP)in ovarian cancer. We first established two DDP-resistant ovarian cancer cell lines. Then, we identified the effect of circ_C20orf11 on specific cellular characteristics (proliferation, apoptosis, DDP resistance) via a series of experiments. The binding sites between circ_C20orf11 and miR-527 and between miR-527 and YWHAZ were predicted using a bioinformatics tool and confirmed with a dual-luciferase reporter assay. Furthermore, extracellular vesicles (EVs) derived from DDP-resistant cell lines were identified, and the effect of EVs on macrophage polarization was examined. circ_C20orf11 was upregulated in ovarian cancer. Increased circ_C20orf11 expression enhanced DDP resistance and cell proliferation and reduced cell apoptosis in DDP-resistant cell lines after DDP treatment by sponging miR-527 and promoting YWHAZ expression. In addition, we found that DDP-resistant cell-derived EVs can induce macrophage M2 polarization, whereas silencing of circ_C20orf11 inhibited EV-induced macrophage M2 polarization. Consistent with these results, silencing of circ_C20orf11 enhanced sensitivity to DDP in vivo. Importantly, we proved that circ_C20orf11 expression was upregulated in EVs extracted from the serum of DDP-resistant patients. Our study demonstrated that silencing circ_C20orf11 sensitizes ovarian cancer to DDP by promoting miR-527/YWHAZ signaling and EV-mediated macrophage M2 polarization.

Future Screening Prospects for Ovarian Cancer

Simple Summary

Ovarian cancer (OC) has the highest mortality rate of all gynecological cancers. It is usually diagnosed in late stages (FIGO III-IV), and therefore, overall survival is very poor. If diagnosed at the early stages, ovarian cancer has a 90% five-year survival rate. Liquid biopsy has a good potential to improve early ovarian cancer detection and is discussed in this review.

Abstract

Current diagnostic tools used in clinical practice such as transvaginal ultrasound, CA 125, and HE4 are not sensitive and specific enough to diagnose OC in the early stages. A lack of early symptoms and an effective asymptomatic population screening strategy leads to a poor prognosis in OC. New diagnostic and screening methods are urgently needed for early OC diagnosis. Liquid biopsies have been considered as a new noninvasive and promising method, using plasma/serum, uterine lavage, and urine samples for early cancer detection. We analyzed recent studies on molecular biomarkers with specific emphasis on liquid biopsy methods and diagnostic efficacy for OC through the detection of circulating tumor cells, circulating cell-free DNA, small noncoding RNAs, and tumor-educated platelets.

Exosomal miR-21-5p contributes to ovarian cancer progression by regulating CDK6

Ovarian cancer is a predominant gynecologic malignancy and correlated with high mortality and severe morbidity. Exosomal microRNAs (miRNAs) play crucial roles in various processes during the progression of ovarian cancer, such as cell proliferation, apoptosis, and invasion. However, the function of exosomal miR-21-5p in ovarian cancer is still unknown. Here, we found that miR-21-5p was upregulated in ovarian cancer tissues, plasma exosomes of ovarian cancer patients, and exosomes from ovarian cancer cells. MiR-21-5p was incorporated in the exosomes from the ovarian cancer cells. In addition, 5-ethynyl-2'-deoxyuridine (Edu), a marker of cancer cell proliferation, was enhanced by miR-21-5p mimic while reduced by miR-21-5p inhibitor in ovarian cancer cells. MiR-21-5p mimic could increase, but miR-21-5p inhibitor could decrease the migration and invasion of cancer cells. Ovarian cancer cell apoptosis was induced by miR-21-5p inhibitor. Moreover, miR-21-5p inhibitor could up-regulate the expression of pro-apoptotic cleaved caspase3 and Bax while downregulate the expression of anti-apoptotic Bcl2 in the cells. Exosomal miR-21-5p inhibited the expression of cyclin-dependent kinase 6 (CDK6) by targeting its 3'-untranslated region (3'-UTR) at both the mRNA and protein levels. Tumorigenicity analysis in nude mice revealed that exosomal miR-21-5p could increase tumor volume, size, and weight of ovarian cancer in vivo. Besides, miR-21-5p targeted CDK6 in tumor tissues of nude mice. In conclusion, exosomal miR-21-5p contributes to the progression of ovarian cancer by regulating CDK6. Our findings will provide novel insights into the mechanism of exosomal miR-21-5p in the development of ovarian cancer. Exosomal miR-21-5p may serve as a potential target for the therapy of ovarian cancer.

Exosomes derived from colon cancer cells and plasma of colon cancer patients promote migration of SW480 cells through Akt/mTOR pathway

OBJECTIVE

To investigate the effect of exosomes derived from colon cancer (CC) cells and plasma of CC patients on migration of SW480 cells.

METHODS

The exosomes derived from culture medium of human colon epithelial cell line NCM460 and CC cell line SW620 were isolated by ultracentrifugation. The exosomes derived from plasma of CC patients and healthy controls were isolated by size exclusion chromatography (SEC). The particle size and morphology of exosomes were identified by nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM) respectively, and exosomal markers were detected by Western blotting. The uptake of fluorescent DiI labeled exosomes by SW480 cells was observed by confocal microscopy. Transwell assay was used to detect the effect of exosomes on the migration of SW480 cells. The expression level of associated proteins in signaling pathway were analyzed by Western blotting. Rapamycin, an inhibitor of mTOR, was used to study the role of mTOR signaling pathway on exosomes mediated migration of SW480 cells.

RESULTS

The results of NTA and TEM showed that the particle size of the isolated exosomes was about 120 nm, which were small vesicles with membrane structure. The expressions of exosomal markers Alix, TSG101 and CD63 could be detected. The exosomes were evidenced by a red fluorescent signal inside the cytoplasm of SW480 recipient cells, and could promote the migration of SW480 cells, which is associated with Akt/mTOR signaling pathway. Compared with the control group, plasma exosomes derived from CC patients could significantly promote the migration of SW480 cells. Inhibition the activity of mTOR signaling could attenuate the migration of SW480 cells.

CONCLUSIONS

Exosomes derived from CC cells and plasma of CC patients could promote the migration of SW480 cells, which is associated with Akt/mTOR signaling pathway.

Exosomes in ovarian cancer ascites promote epithelial-mesenchymal transition of ovarian cancer cells by delivery of miR-6780b-5p

The poor prognosis of ovarian cancer is mainly due to metastasis, and the specific mechanism underlying ovarian cancer metastasis is not clear. Ascites-derived exosomes (ADEs) play an important role in the progression of ovarian cancer, but the mechanism is unknown. Here, we found that ADEs promoted ovarian cancer metastasis not only in vitro but also in vivo. This promotive function was based on epithelial-mesenchymal transition (EMT) of ovarian cancer cells. Bioinformatics analysis of RNA sequencing microarray data indicated that miR-6780b-5p may be the key microRNA (miRNA) in ADEs that facilitates cancer metastasis. Moreover, the expression of exosomal miR-6780b-5p correlated with tumor metastasis in ovarian cancer patients. miR-6780b-5p overexpression promoted and miR-6780b-5p downregulation suppressed EMT of ovarian cancer cells. These results suggest that ADEs transfer miR-6780b-5p to ovarian cancer cells, promoting EMT and finally facilitating ovarian cancer metastasis.

Exosomal microRNAs and exosomal long non-coding RNAs in gynecologic cancers

Gynecologic cancer is a group of any malignancies affecting reproductive tissues and organs of women, including ovaries, uterine, cervix, vagina, vulva, and endometrium. Several types of molecular mechanisms are associated with the progression of gynecologic cancers. Among it can be referred to the most widely studied non-coding RNAs (ncRNAs), specifically microRNAs (miRNAs) and long ncRNAs (lncRNAs). As yet, lncRNAs are known to serve key biological roles via various mechanisms, such as splicing regulation, chromatin rearrangement, translation regulation, cell-cycle control, genetic imprinting and mRNA decay. Besides, miRNAs govern gene expression by modulation of mRNAs and lncRNAs degradation, suggestive of needing more research in this field. Generally, driving gynecological cancers pathways by miRNAs and lncRNAs lead to the current improvement in cancer-related technologies. Exosomes are extracellular microvesicles which can carry cargo molecules among cells. In recent years, more studies have been focused on exosomal non-coding RNAs (exo-ncRNAs) and exosomal microRNAs (exo-miRs) because of being natural carriers of lnc RNAs and microRNAs via programmed process. In this review we summarized recent reports concerning the function of exosomal microRNAs and exosomal long non-coding RNAs in gynecological cancers.

Ligustrazine inhibits the proliferation and migration of ovarian cancer cells via regulating miR-211

Ovarian cancer (OC) is a commonly diagnosed female cancer. Ligustrazine (LSZ), a natural compound, has been reported to exert anti-cancer activity, although the mechanisms underlying the anti-cancer effects are not clear. The present study investigated the impact of LSZ on cell proliferation and migration by regulating microRNA-211 (miR-211) expression using the human ovarian cancer SK-OV-3 and OVCAR-3 cell lines. OC cells were treated with 0, 0.5, 1, and 2 mM LSZ, and quantitative real-time PCR was utilized to measure miR-211 levels in SK-OV-3 and OVCAR-3 cells with different treatment. Moreover, to further confirm the roles of miR-211 in LSZ induced anti-tumor effects, miR-211 expression was inhibited by transfection of miR-211 inhibitors in SK-OV-3 cells. Cell proliferation of transfected cells was evaluated using the CCK-8 and colony formation assay. The scratch assay was employed to assess cell migration and transwell assay was performed for evaluating the cell invasion. Protein levels of epithelial–mesenchymal transition (EMT) markers were determined by Western blotting. We found that LSZ inhibited the viability, proliferation, migration and invasion ability of SK-OV-3 and OVCAR-3 cells in a dose-dependent manner; moreover, LSZ could significantly increase the expression of miR-211 in both SK-OV-3 and OVCAR-3, and knockdown of miR-211 in SK-OV-3 cells partially abrogated the anti-tumor behavior of LSZ by promoting the viability, proliferation, migration, invasion and EMT of SK-OV-3 cells. Thus, we found that LSZ can inhibit the proliferation and migration of OC cells via regulating miR-211. Our study suggests that LSZ might be a potential and effective treatment for OC.

Extracellular vesicle-based liquid biopsy holds great promise for the management of ovarian cancer

Ovarian cancer is a highly lethal gynecological disease because most patients are diagnosed in advanced stages due to a lack of appropriate markers or methods for early detection. Extracellular vesicles (EVs) are small biological vesicles released by all types of cells and are widely distributed in biofluids. These vesicles and their bioactive contents are involved in various aspects of tumorigenesis and development, and some of them could be detected in biofluids from liquid biopsy and used as markers for cancer management. Liquid biopsy is a recently developed method for disease diagnosis and real-time monitoring by detecting biomolecules in biofluids such as plasma. The operation is minimally invasive and relatively convenient, especially for patients with cancer. In this review, we describe the use of EV-based liquid biopsy in ovarian cancer and summarize recent advances in technologies for EV isolation and detection, as well as biomarkers identified from ovarian cancer-derived EVs, with a focus on their potential roles in diagnosis and progression monitoring. Although the advantages of liquid biopsy make this approach promising, some technological challenges remain, and qualified biomarkers for clinical use are still being explored.

Elevated expression of exosomal microRNA-21 as a potential biomarker for the early diagnosis of pancreatic cancer using a tethered cationic lipoplex nanoparticle biochip

Pancreatic cancer (PC) has a poor prognosis due to the lack of effective molecular biomarkers for early diagnosis. Recent studies have investigated the use of exosomal microRNAs (exmiRs) as diagnostic biomarkers in cancer. The present study examined exmiR-21, exmiR-10b and exmiR-212-3p expression in patients with PC and healthy individuals. The expression levels of exmiR-21, exmiR-10b and exmiR-212-3p were examined in the peripheral blood plasma of 36 patients with PC and 65 healthy controls, using tethered cationic lipoplex nanoparticle biochip. The levels of exmiR-21 in the plasma of 34 mice were also evaluated. The expression levels of exmiR-21 and exmiR-10b were significantly greater in patients with PC compared with the control group. The receiver operating characteristic (ROC) analysis indicated that exmiR-21 had better diagnostic performance (P=0.0003; AUC, 0.7171) compared with the other two exmiRs. The diagnostic value of exmiR-21 improved when combined with exmiR-10b (P<0.0001; AUC, 0.791). Furthermore, exmiR-21 was capable of distinguishing patients with early-stage PC from controls and advanced-stage PC (P<0.05, early stage vs. healthy; P<0.001, early stage vs. advanced stage). The results of the present study revealed that the plasma levels of exmiR-21 and exmiR-10b were upregulated in patients with PC. The ROC analyses indicated that exmiR-21 had the best diagnostic performance among the three exmiRs. Furthermore, exmiR-21 was capable of discriminating patients with early-stage PC from healthy controls. These findings indicate the potential of determining the expression of exmiR-21 from serum using a tethered cationic lipoplex nanoparticle biochip as a novel non-invasive strategy for the early diagnosis of PC.

microRNA-214 Prevents Traits of Cutaneous Squamous Cell Carcinoma via VEGFA and Bcl-2

BACKGROUND

Dysregulation of microRNA-214 (miR-214) has been indicated in different tumors. The function of miR-214 in cutaneous squamous cell carcinoma (CSCC) is yet to be deciphered. The current study aimed to investigate the specific mechanism underpinning CSCC development with the involvement of miR-214 and its putative targets.

METHODS

Microarray analysis of CSCC and adjacent tissues was carried out to filter the most significant downregulated miRNA. Survival analysis of patients was subsequently implemented, followed by miRNA expression determination in CSCC cells. Gain-of-function assays were performed to evaluate its function on cellular level. The targets of the determined miRNA were predicted and their expression in CSCC and adjacent tissues was evaluated. The targeting relationship was analyzed by dual-luciferase assays. Finally, rescue experiments were conducted.

RESULTS

miR-214 was reduced in CSCC tissues and cells, and the survival of patients harboring overexpression of miR-214 was higher. miR-214 restoration increased CSCC cell apoptosis, while decreased proliferative, invasive and migratory activities. miR-214 interacted with vascular endothelial growth factor A (VEGFA) and B-cell CLL/lymphoma 2 (Bcl-2). VEGFA and Bcl-2, overexpressed in CSCC tissues and cells, were negatively correlated with miR-214. Moreover, VEGFA and Bcl-2 overexpression reversed the anti-tumor phenotypes of miR-214 on CSCC cells. miR-214 disrupted the Wnt/β-catenin pathway through VEGFA and Bcl-2 in the CSCC cells.

CONCLUSION

Our data demonstrates that miR-214 exerts a suppressing role in CSCC. The discovery of novel targets such as miR-214 and VEGFA/Bcl-2 may facilitate the development of therapeutic options.