Serum exosomal microRNA-766-3p expression is associated with poor prognosis of esophageal squamous cell carcinoma

Exosomes in esophageal cancer: a promising frontier for liquid biopsy in diagnosis and therapeutic monitoring

Esophageal cancer is a common and lethal digestive system malignancy, and both treatment efficacy and patient survival rates face significant challenges. In recent years, exosomes have emerged as crucial mediators of intercellular communication, demonstrating tremendous clinical potential, particularly in the diagnosis, treatment, and prognostic evaluation of esophageal cancer. These exosomes not only serve as biomarkers for early diagnosis and prognosis but also modulate tumor growth, metastasis, and drug resistance by delivering bioactive molecules. Importantly, exosomes can act as carriers for esophageal cancer-related therapeutic agents, optimizing gene therapy strategies to enhance efficacy while reducing toxicity and side effects. Despite facing challenges in clinical applications such as purification, enrichment, and standardization of analytical methods, exosomes maintain broad prospects for application in esophageal cancer treatment, with the potential to significantly improve patient outcomes and quality of life. This review focuses on the innovative role of exosomes in the early diagnosis of esophageal cancer, exploring their application value and safety in disease monitoring and assessment of treatment response. Furthermore, this study outlines the challenges and limitations of transitioning exosome research from basic studies to clinical applications, as well as potential solutions and future research directions to address these obstacles.

Exosomes in esophageal cancer: function and therapeutic prospects

Esophageal cancer (EC) is one of the most common malignant tumors worldwide. Exosomes are a type of extracellular vesicles produced by eukaryotic cells and present in all body fluids. Recent studies have revealed that exosomes can be used as a tool for cell signaling and have great potential in cancer diagnosis and treatment strategies. This article reviews the research progress of exosomes in EC in recent years, mainly including the mechanism of action, diagnostic markers, therapeutic targets, and drug carriers. The challenges faced are discussed to provide guidelines for further research in future.

Extracellular vesicles and the "six Rs" in radiotherapy

Over half of patients with cancer receive radiation therapy during the course of their disease. Decades of radiobiological research have identified 6 parameters affecting the biological response to radiation referred to as the 6 "Rs": Repair, Radiosensitivity, Repopulation, Redistribution, Reoxygenation, and Reactivation of the anti-tumour immune response. Extracellular Vesicles (EVs) are small membrane-bound particles whose multiple biological functions are increasingly documented. Here we discuss the evidence for a role of EVs in the orchestration of the response of cancer cells to radiotherapy. We highlight that EVs are involved in DNA repair mechanisms, modulation of cellular sensitivity to radiation, and facilitation of tumour repopulation. Moreover, EVs influence tumour reoxygenation dynamics, and play a pivotal role in fostering radioresistance. Last, we examine how EV-related strategies could be translated into novel strategies aimed at enhancing the efficacy of radiation therapy against cancer.

Exosomes in esophageal cancer: Promising nanocarriers in cancer progression, diagnosis, prognosis, and therapy

Esophageal cancer (EC) is one of the most fatal cancers all over the world. Sensitive detection modalities for early-stage EC and efficient treatment methods are urgently needed for the improvement of the prognosis of EC. Exosomes are small vesicles for intercellular communication, mediating many biological responses including cancer progression, which are not only promising biomarkers for diagnosis and prognosis but also therapeutic tools for EC. This review provides an overview of the relationships between exosomes and EC progression, as well as the application of exosomes in the diagnosis, prognosis, and treatment of EC. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

The roles of exosomes in esophageal cancer

The incidence and mortality rate of esophageal cancer (EC) are higher worldwide. Exosomes are nanoscale vesicles derived from various types of cells, exhibiting a stable presence in bodily fluids, and contain a plethora of bioactive components including proteins, DNA, and RNA. Exosomes can mediate cell-to-cell communication and signaling. Numerous studies conducted both domestically and internationally have indicated the significant involvement of exosomes in tumor development and their potential as novel diagnostic and prognostic biomarkers for liquid biopsy. This review seeks to consolidate the role of exosomes and bioactive substances in the progression of EC and elaborate on the opportunities and challenges associated with the clinical application of exosomes in EC.

Liquid biopsy of oesophageal squamous cell carcinoma: implications in diagnosis, prognosis, and treatment monitoring

Oesophageal squamous cell carcinoma (ESCC) is a common malignant tumour of the gastrointestinal tract. Early detection and access to appropriate treatment are crucial for the long-term survival of patients. However, limited diagnostic and monitoring methods are available for identifying early stage ESCC. Endoscopic screening and surgical resection are commonly used to diagnose and treat early ESCC. However, these methods have disadvantages, such as high recurrence, lethality, and mortality rates. Therefore, methods to improve early diagnosis of ESCC and reduce its mortality rate are urgently required. In 1961, Gary et al. proposed a novel liquid biopsy approach for clinical diagnosis. This involved examining exosomes, circulating tumour cells, circulating free DNA, and circulating free RNA in body fluids. The ability of liquid biopsy to obtain samples repeatedly, wide detection range, and fast detection speed make it a feasible option for non-invasive tumour detection. In clinical practice, liquid biopsy technology has gained popularity for early screening, diagnosis, treatment efficacy monitoring, and prognosis assessment. Thus, this is a highly promising examination method. However, there have been no comprehensive reviews on the four factors of liquid biopsy in the context of ESCC. This review aimed to analyse the progress of liquid biopsy research for ESCC, including its classification, components, and potential future applications.

MicroRNAs: A novel signature in the metastasis of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is a malignant epithelial tumor, characterized by squamous cell differentiation, it is the sixth leading cause of cancer-related deaths globally. The increased mortality rate of ESCC patients is predominantly due to the advanced stage of the disease when discovered, coupled with higher risk of metastasis, which is an exceedingly malignant characteristic of cancer, frequently leading to a high mortality rate. Unfortunately, there is currently no specific and effective marker to predict and treat metastasis in ESCC. MicroRNAs (miRNAs) are a class of small non-coding RNA molecules, approximately 22 nucleotides in length. miRNAs are vital in modulating gene expression and serve pivotal regulatory roles in the occurrence, progression, and prognosis of cancer. Here, we have examined the literature to highlight the intimate correlations between miRNAs and ESCC metastasis, and show that ESCC metastasis is predominantly regulated or regulated by genetic and epigenetic factors. This review proposes a potential role for miRNAs as diagnostic and therapeutic biomarkers for metastasis in ESCC metastasis, with the ultimate aim of reducing the mortality rate among patients with ESCC.

Comprehensive landscape and future perspectives of non-coding RNAs in esophageal squamous cell carcinoma, a bibliometric analysis from 2008 to 2023

Objectives: Summarize the progress and hot topic evolution of non-coding RNAs (ncRNAs) research in esophageal squamous cell carcinoma (ESCC) in recent years and predict future research directions. Methods: Relevant articles from the Web of Science until 31 October 2023 were obtained. Bibliometric analysis of included articles was performed using software (VOSviewer, CiteSpace, and Bibliometrix). The volume and citation of publications, as well as the country, institution, author, journal, keywords of the articles were used as variables to analyze the research trends and hot spot evolution. Results: 1,118 literature from 2008 to 2023 were retrieved from database, with 25 countries/regions, 793 institutions, 5,426 authors, 261 journals involved. Global cooperation was centered on China, Japan, and the United States. Zhengzhou University, an institution from China, had the highest publication. The most prolific author was Guo Wei, and the most prolific journal was Oncology Letters. Analysis of keywords revealed that the research in this field revolved around the role of ncRNAs in the occurrence, development, diagnosis, treatment, and prognosis of ESCC, mainly including micro RNAs, long non-coding RNAs, and then circular RNAs. Conclusion: Overall, research on ncRNAs in ESCC remains strong. Previous research has mainly focused on the basic research, with a focus on the mechanism of ncRNAs in the occurrence, development, diagnosis, treatment, and prognosis of ESCC. Combining current research with emerging disciplines to further explore its mechanisms of action or shifting the focus of research from preclinical research to clinical research based on diagnosis, treatment, and prognosis, will be the main breakthrough in this field in the future.

Prediction of Response to Chemoradiotherapy by Dynamic Changes of Circulating Exosome Levels in Patients with Esophageal Squamous Cell Carcinoma

Background

The exosomes-based liquid biopsy represents a prospective biomarker for tumor screening, prognosis prediction, and tumor regression. This study aimed to isolate circulating exosomes (CEs) from plasma of the esophageal squamous cell carcinoma (ESCC) patients who received chemoradiotherapy through exosome detection method via the ultrafast-isolation system (EXODUS) and investigated the association between the dynamic changes of CE levels and therapeutic effect.

Methods

We isolated and quantitatively analyzed CEs from plasma of locally advanced ESCC patients received chemoradiotherapy at 2 time points: baseline (pre-chemoradiotherapy) and 2 months after the chemoradiotherapy (post-chemoradiotherapy). We isolated exosomes from plasma by EXODUS platform and confirmed them through nanoparticle tracking analysis (NTA), transmission electron microscope (TEM), and Western blot. The associations of CE level with clinicopathological characteristics, tumor regression, and progression-free survival (PFS) were analyzed.

Results

The average diameter of CEs was 107.4±14.3 nm at baseline and 101.7±17.1 nm at post-chemoradiotherapy. The mean exosome concentration significantly decreased after chemoradiotherapy (7.3×1011 particles/mL vs 5.4×1011 particles/mL, P < 0.001). The patients with stage III-IVA and tumor length ≥5cm had obviously higher baseline CE levels. Dynamic changes in CE levels were successfully applied for evaluation of chemoradiotherapy response and PFS. Furthermore, through multivariate Cox regression analysis, it was revealed that dynamic changes of CE levels were an independent predictor of PFS in locally advanced ESCC patients who received chemoradiotherapy.

Conclusion

Here, we demonstrated EXODUS platform isolated and enriched CEs from plasma of ESCC patients with high-purity and high-yield. The EXODUS platform can facilitate liquid biopsy based on exosomes translation to the clinic. Baseline CE levels can reflect ESCC tumor burden. The dynamic changes of CE levels during chemoradiotherapy allow the prediction of treatment effect and PFS of ESCC patients, requiring further investigations in larger patient cohorts.

Extracellular vesicles associated microRNAs: Their biology and clinical significance as biomarkers in gastrointestinal cancers

Gastrointestinal (GI) cancers, including colorectal, gastric, esophageal, pancreatic, and liver, are associated with high mortality and morbidity rates worldwide. One of the underlying reasons for the poor survival outcomes in patients with these malignancies is late disease detection, typically when the tumor has already advanced and potentially spread to distant organs. Increasing evidence indicates that earlier detection of these cancers is associated with improved survival outcomes and, in some cases, allows curative treatments. Consequently, there is a growing interest in the development of molecular biomarkers that offer promise for screening, diagnosis, treatment selection, response assessment, and predicting the prognosis of these cancers. Extracellular vesicles (EVs) are membranous vesicles released from cells containing a repertoire of biological molecules, including nucleic acids, proteins, lipids, and carbohydrates. MicroRNAs (miRNAs) are the most extensively studied non-coding RNAs, and the deregulation of miRNA levels is a feature of cancer cells. EVs miRNAs can serve as messengers for facilitating interactions between tumor cells and the cellular milieu, including immune cells, endothelial cells, and other tumor cells. Furthermore, recent years have witnessed considerable technological advances that have permitted in-depth sequence profiling of these small non-coding RNAs within EVs for their development as promising cancer biomarkers -particularly non-invasive, liquid biopsy markers in various cancers, including GI cancers. Herein, we summarize and discuss the roles of EV-associated miRNAs as they play a seminal role in GI cancer progression, as well as their promising translational and clinical potential as cancer biomarkers as we usher into the area of precision oncology.

Role of exosomes in metastasis and therapeutic resistance in esophageal cancer

Esophageal cancer (EC) has a high incidence and mortality rate and is emerging as one of the most common health problems globally. Owing to the lack of sensitive detection methods, uncontrollable rapid metastasis, and pervasive treatment resistance, EC is often diagnosed in advanced stages and is susceptible to local recurrence. Exosomes are important components of intercellular communication and the exosome-mediated crosstalk between the cancer and surrounding cells within the tumor microenvironment plays a crucial role in the metastasis, progression, and therapeutic resistance of EC. Considering the critical role of exosomes in tumor pathogenesis, this review focused on elucidating the impact of exosomes on EC metastasis and therapeutic resistance. Here, we summarized the relevant signaling pathways involved in these processes. In addition, we discussed the potential clinical applications of exosomes for the early diagnosis, prognosis, and treatment of EC.

Serum‑derived exosomal hsa‑let‑7b‑5p as a biomarker for predicting the severity of coronary stenosis in patients with coronary heart disease and hyperglycemia

Exosomal microRNAs (miRNAs/miRs) are potential biomarkers for the diagnosis and treatment of cardiovascular disease, and hyperglycemia serves an important role in the development of atherosclerosis. The present study aimed to investigate the expression profile of serum‑derived exosomal miRNAs in coronary heart disease (CHD) with hyperglycemia, and to identify effective biomarkers for predicting coronary artery lesions. Serum samples were collected from eight patients with CHD and hyperglycemia and eight patients with CHD and normoglycemia, exosomes were isolated and differentially expressed miRNAs (DEMIs) were filtered using a human miRNA microarray. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed using standard enrichment computational methods for the target genes of DEMIs. Receiver operating characteristic (ROC) curve analysis was applied to evaluate the values of the selected DEMIs in predicting the severity of coronary stenosis. A total of 10 DEMIs, including four upregulated miRNAs (hsa‑let‑7b‑5p, hsa‑miR‑4313, hsa‑miR‑4665‑3p and hsa‑miR‑940) and six downregulated miRNAs (hsa‑miR‑4459, hsa‑miR‑4687‑3p, hsa‑miR‑6087, hsa‑miR‑6089, hsa‑miR‑6740‑5p and hsa‑miR‑6800‑5p), were screened in patients with CHD and hyperglycemia. GO analysis showed that the 'cellular process', 'single‑organism process' and 'biological regulation' were significantly enriched. KEGG pathway analysis revealed that the 'mTOR signaling pathway', 'FoxO signaling pathway' and 'neurotrophin signaling pathway' were significantly enriched. Among these DEMIs, only hsa‑let‑7b‑5p expression was positively correlated with both hemoglobin A1C levels and Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery score. ROC curves showed that hsa‑let‑7b‑5p could serve as an effective biomarker for differentiating the severity of coronary stenosis. In conclusion, the present study demonstrated that serum‑derived exosomal hsa‑let‑7b‑5p is upregulated in patients with CHD and hyperglycemia, and may serve as a noninvasive biomarker for the severity of coronary stenosis.

Identification of combinatorial miRNA panels derived from extracellular vesicles as biomarkers for esophageal squamous cell carcinoma

MicroRNAs (miRNAs) are relatively stable in blood, emerging as one of the most promising biomarkers in tumor liquid biopsy. Both total and extracellular vesicles (EVs) encapsulated miRNA have been studied for prognostic potential in a variety of cancers. Here, we systematically compared and verified the total and vesicle-derived miRNA expression profiles from plasma samples in healthy controls and patients with esophageal squamous cell carcinoma (ESCC). In the present study, four miRNA species miR-636, miR-7641, miR-28-3p, and miR-1246 that were differentially expressed in ESCC patients were chosen for further study. We first elucidated their essential function in ESCC progression and further explored their preliminary mechanism by identifying target proteins and involving signal pathways. Subsequently, the prognostic miRNA panels including miR-636, miR-7641, miR-1246, and miR-28-3p for ESCC diagnosis were constructed and validated using different cohort. Our results showed that the panel including the above four miRNAs derived from plasma EVs was most effective in distinguishing tumor patients from normal subjects, while integrated plasma EVs-derived miR-1246, miR-28-3p and total plasma miRNAs miR-636, miR-7641 showed the best capability in predicting lymph node metastasis. In summary, our studies revealed that plasma EVs-derived miRNAs could be emerged as promising biomarkers for ESCC diagnosis.

Glimepiride Compared to Liraglutide Increases Plasma Levels of miR-206, miR-182-5p, and miR-766-3p in Type 2 Diabetes Mellitus: A Randomized Controlled Trial

BACKGRUOUND

Diabetes is a chronic disease with several long-term complications. Several glucose-lowering drugs are used to treat type 2 diabetes mellitus (T2DM), e.g., glimepiride and liraglutide, in which both having different modes of action. Circulating microRNAs (miRNAs) are suggested as potential biomarkers that are associated with the disease development and the effects of the treatment. In the current study we evaluated the effect of glimepiride, liraglutide on the expression of the circulating miRNAs.

METHODS

The present study is a post hoc trial from a previously randomized control trial comparing liraglutide versus glimepiride both in combination with metformin in subjects with T2DM, and subclinical heart failure. miRNAs were determined in the subjects' serum samples with next generation sequencing. Expression patterns of the circulating miRNAs were analyzed using bioinformatic univariate and multivariate analyses (clinical trial registration: NCT01425580).

RESULTS

Univariate analyses show that treatment with glimepiride altered expression of three miRNAs in patient serum, miR-206, miR-182-5p, and miR-766-3p. Both miR-182-5p and miR-766-3p were also picked up among the top contributing miRNAs with penalized regularised logistic regressions (Lasso). The highest-ranked miRNAs with respect to Lasso coefficients were miR-3960, miR-31-5p, miR-3613-3p, and miR-378a-3p. Liraglutide treatment did not significantly influence levels of circulating miRNAs.

CONCLUSION

Present study indicates that glucose-lowering drugs differently affect the expression of circulating miRNAs in serum in individuals with T2DM. More studies are required to investigate possible mechanisms by which glimepiride is affecting the expression of circulating miRNAs.

Mechanisms of function and clinical potential of exosomes in esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) remains one of the most lethal and widespread malignancies in China. Exosomes, a subset of tiny extracellular vesicles manufactured by all cells and present in all body fluids, contribute to intercellular communication and have become a focus of the search for new therapeutic strategies for cancer. A number of global analyses of exosome-mediated functions and regulatory mechanism in malignant diseases have recently been reported. There is extensive evidence that exosomes can be used as diagnostic and prognostic markers for cancer. However, our understanding of their clinical value and mechanisms of action in ESCC is still limited and has not been systematically reviewed. Here, we review current research specifically focused on the functions and mechanisms of action of ESCC tumor-derived exosomes and non-ESCC-derived exosomes in ESCC progression and describe opportunities and challenges in the clinical translation of exosomes.

Extracellular Vesicles Are Important Mediators That Regulate Tumor Lymph Node Metastasis via the Immune System

Extracellular vesicles (EVs) are particles with a lipid bilayer structure, and they are secreted by various cells in the body. EVs interact with and modulate the biological functions of recipient cells by transporting their cargoes, such as nucleic acids and proteins. EVs influence various biological phenomena, including disease progression. They also participate in tumor progression by stimulating a variety of signaling pathways and regulating immune system activation. EVs induce immune tolerance by suppressing CD8⁺ T-cell activation or polarizing macrophages toward the M2 phenotype, which results in tumor cell proliferation, migration, invasion, and metastasis. Moreover, immune checkpoint molecules are also expressed on the surface of EVs that are secreted by tumors that express these molecules, allowing tumor cells to not only evade immune cell attack but also acquire resistance to immune checkpoint inhibitors. During tumor metastasis, EVs contribute to microenvironmental changes in distant organs before metastatic lesions appear; thus, EVs establish a premetastatic niche. In particular, lymph nodes are adjacent organs that are connected to tumor lesions via lymph vessels, so that tumor cells metastasize to draining lymph nodes at first, such as sentinel lymph nodes. When EVs influence the microenvironment of lymph nodes, which are secondary lymphoid tissues, the immune response against tumor cells is weakened; subsequently, tumor cells spread throughout the body. In this review, we will discuss the association between EVs and tumor progression via the immune system as well as the clinical application of EVs as biomarkers and therapeutic agents.

Exosomal miR-10527-5p Inhibits Migration, Invasion, Lymphangiogenesis and Lymphatic Metastasis by Affecting Wnt/β-Catenin Signaling via Rab10 in Esophageal Squamous Cell Carcinoma

Background

Cancer cell-derived exosomal microRNAs (miRNAs) play critical role in orchestrating intercellular communication between tumor cells and tumor microenvironmental factors, including lymphatic endothelial cells (LECs). Nevertheless, the functions and underlying mechanisms of exosomal miRNAs in lymphatic metastasis and lymphangiogenesis in esophageal squamous cell carcinoma (ESCC) remain unclear.

Methods

Small RNA sequencing, Gene Expression Omnibus (GEO) analysis and qRT‒PCR were performed to identify the candidate exosomal miRNAs involved in ESCC metastasis. Receiver operating characteristic curve analysis was conducted to evaluate the diagnostic potential of exosomal miR-10527-5p in predicting lymph node metastasis (LNM) status. An in vitro coculture system was used to investigate the effects of exosomal miR-10527-5p on ESCC cells and human LECs (HLECs), followed by a popliteal LNM assay in vivo. The relationship between miR-10527-5p and Rab10 was identified by dual-luciferase reporter, fluorescence in situ hybridization and qRT‒PCR assays. Then, a series of rescue assays were performed to further investigate whether Rab10 is involved in exosomal miR-10527-5p mediated ESCC metastasis.

Results

MiR-10527-5p was found to be notably reduced in both the plasma exosomes and tumor tissues of ESCC patients with LNM, and plasma exosomal miR-10527-5p had a high sensitivity and specificity for discrimination of LNM status. Moreover, exosome-shuttled miR-10527-5p suppressed the migration, invasion and epithelial-to-mesenchymal transition (EMT) of ESCC cells as well as the migration and tube formation of HLECs via Wnt/β-catenin signaling in vitro and in vivo. Further investigation revealed that Rab10 was a direct target of miR-10527-5p, and re-expression of Rab10 neutralized the inhibitory effects of exosomal miR-10527-5p.

Conclusion

Our study demonstrated that exosomal miR-10527-5p had a strong capability to predict preoperative LNM status and anti-lymphangiogenic effect. Exosomal miR-10527-5p inhibited lymphangiogenesis and lymphatic metastasis of ESCC in a vascular endothelial growth factor-C (VEGF-C)-independent manner, showing potential as a therapeutic target for ESCC patients.

Exosomal microRNAs: A Diagnostic and Therapeutic Small Bio-molecule in Esophageal Cancer

Esophageal cancer (EC) is one of the major causes of cancer-related death worldwide. EC is usually diagnosed at a late stage, and despite aggressive therapy, the five-year survival rate of patients remains poor. Exosomes play important roles in cancer biology. Indeed, exosomes are implicated in tumor proliferation, angiogenesis, and invasion. They contain bioactive molecules such as lipids, proteins, and non-coding RNAs. Exosome research has recently concentrated on microRNAs, which are tiny noncoding endogenous RNAs that can alter gene expression and are linked to nearly all physiological and pathological processes, including cancer. It is suggested that deregulation of miRNAs results in cancer progression and directly induces tumor initiation. In esophageal cancer, miRNA dysregulation plays an important role in cancer prognosis and patients' responsiveness to therapy, indicating that miRNAs are important in tumorigenesis. In this review, we summarize the impact of exosomal miRNAs on esophageal cancer pathogenesis and their potential applications for EC diagnosis and therapy.

Proteomic profiling of plasma exosomes reveals CD82 involvement in the development of esophageal squamous cell carcinoma

The Xinjiang Uygur autonomous region has a high incidence of esophageal cancer. For the early diagnosis of patients with esophageal squamous cell carcinoma (ESCC), exosomes were isolated and quantified by liquid chromatography tandem mass spectrometry ((LC-MS/MS) with data independent acquisition (DIA) from the peripheral blood of patients with benign esophageal disease (BED), esophageal intraepithelial neoplasia (EIN) and ESCC. A total of 1117 proteins were identified in the above 9 samples. The proteomic results showed that the quantity of CD82 in exosomes of EIN was significantly higher than that in patients with BED and ESCC. Meanwhile, our ELISA test verified our proteomic results. In addition, the immunohistochemical results showed high CD82 expression in adjacent normal tissues and low expression in ESCC tissues. CD82 expression in ESCC tissues was negatively correlated with tumor stage and the expression of PKM2, and the high expression of CD82 combined with low expression of PKM2 in ESCC tissues suggested a good prognosis. To further clarify the tumor suppressive mechanism of CD82, the TIMER and TISDB databases were analyzed, and CD82 expression in tumor tissues was found to be related to the infiltration of immune cells. CD82 in exosomes is involved in the development of ESCC. SIGNIFICANCE: Xinjiang is a high incidence area of ESCC. When diagnosed in the middle and late stages of the disease, the prognosis of patients is poor. Exosomes provide the possibility of relatively noninvasive and early detection of esophageal carcinogenesis. To the best of our knowledge, this was the first study using the DIA technique to analyze the exosomal proteins of patients with different stages of ESCC. The proteins identified in the exosomes in these three groups could provide insights for understanding how exosomes promote the occurrence of ESCC, the antitumour mechanism of humans and the early diagnosis of ESCC.

Healthy Serum-Derived Exosomes Improve Neurological Outcomes and Protect Blood–Brain Barrier by Inhibiting Endothelial Cell Apoptosis and Reversing Autophagy-Mediated Tight Junction Protein Reduction in Rat Stroke Model

Blood–brain barrier (BBB) dysfunction causing edema and hemorrhagic transformation is one of the pathophysiological characteristics of stroke. Protection of BBB integrity has shown great potential in improving stroke outcome. Here, we assessed the efficacy of exosomes extracted from healthy rat serum in protection against ischemic stroke in vivo and in vitro. Exosomes were isolated by gradient centrifugation and ultracentrifugation and exosomes were characterized by transmission electron microscopy (TEM) and nanoparticle tracking video microscope. Exosomes were applied to middle cerebral artery occlusion (MCAO) rats or brain microvascular endothelial cell line (bEnd.3) subjected to oxygen-glucose deprivation (OGD) injury. Serum-derived exosomes were injected intravenously into adult male rats 2 h after transient MCAO. Infarct volume and gross cognitive function were assessed 24 h after reperfusion. Poststroke rats treated with serum-derived exosomes exhibited significantly reduced infarct volumes and enhanced neurological function. Apoptosis was assessed via terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick-end labeling (TUNEL) staining and the expression of B-cell lymphoma-2 (Bcl-2), Bax, and cleaved caspase-3 24 h after injury. Our data showed that serum exosomes treatment strikingly decreased TUNEL⁺ cells in the striatum, enhanced the ratio of Bcl-2 to Bax, and inhibited cleaved caspase-3 production in MCAO rats and OGD/reoxygenation insulted bEnd.3 cells. Under the consistent treatment, the expression of microtubule-associated protein 1 light chain 3B-II (LC3B-II), LC3B-I, and Sequestosome-1 (SQSTM1)/p62 was detected by Western blotting. Autolysosomes were observed via TEM. We found that serum exosomes reversed the ratio of LC3B-II to LC3B-I, prevented SQSTM1/p62 degradation, autolysosome formation, and autophagic flux. Together, these results indicated that exosomes isolated from healthy serum provided neuroprotection against experimental stroke partially via inhibition of endothelial cell apoptosis and autophagy-mediated BBB breakdown. Intravenous serum-derived exosome treatment may, therefore, provide a novel clinical therapeutic strategy for ischemic stroke.

CircAGFG1 acts as a sponge of miR-4306 to stimulate esophageal cancer progression by modulating MAPRE2 expression

OBJECTIVE

This work aims to determine the role of circular RNA (circRNA) AGFG1 and related molecular mechanism in esophageal squamous cell carcinoma (ESCC) cells.

METHODS

CircAGFG1 expression in ESCC cell lines was probed with qRT-PCR. ESCC cells were transfected/cotransfected with si-circAGFG1, pcDNA3.1-circAGFG1, si-Microtubule Associated Protein RP/EB Family Member 2 (MAPRE2), pcDNA3.1-circAGFG1 + miR-4306 mimic or pcDNA3.1-circAGFG1 + si-MAPRE2. The interactions between circAGFG1 and miR-4306 as well as miR-4306 and MAPRE2 were confirmed by dual-luciferase reporter assay. Cell proliferation, migration and invasion were detected by CCK-8, cell scratch and Transwell assays, respectively. Relative RNA expression levels of circAGFG1, miR-4306 and MAPRE2 in ESCC cells were measured by qRT-PCR. The protein level of MAPRE2 in ESCC cells was monitored by Western blot.

RESULTS

CircAGFG1 was observably upregulated in ESCC cell lines. Besides, circAGFG1 silencing hindered ESCC cell development in vitro, and these effects were enhanced by miR-4306 overexpression or MAPRE2 silencing. Mechanistic analysis evidenced that circAGFG1 might act as a competitive endogenous RNA of miR-4306 to relieve the repressive effect of miR-4306 on its target MAPRE2.

CONCLUSION

CircAGFG1 facilitates ESCC progression via the miR-4306/MAPRE2 axis, and it may act as a possible biomarker for therapy and diagnosis in ESCC treatment.

Small Extracellular Vesicles in the Development, Diagnosis, and Possible Therapeutic Application of Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) persists among the most lethal and broad-spreading malignancies in China. The exosome is a kind of extracellular vesicle (EV) from about 30 to 200 nm in diameter, contributing to the transfer of specific functional molecules, such as metabolites, proteins, lipids, and nucleic acids. The paramount role of exosomes in the formation and development of ESCC, which relies on promoting intercellular communication in the tumor microenvironment (TME), is manifested with immense amounts. Tumor-derived exosomes (TDEs) participate in most hallmarks of ESCC, including tumorigenesis, invasion, angiogenesis, immunologic escape, metastasis, radioresistance, and chemoresistance. Published reports have delineated that exosome-encapsulated cargos like miRNAs may have utility in the diagnosis, as prognostic biomarkers, and in the treatment of ESCC. This review summarizes the function of exosomes in the neoplasia, progression, and metastasis of ESCC, which improves our understanding of the etiology and pathogenesis of ESCC, and presents a promising target for early diagnostics in ESCC. However, recent studies of exosomes in the treatment of ESCC are sparse. Thus, we introduce the advances in exosome-based methods and indicate the possible applications for ESCC therapy in the future.

The Significance of Exosomes in Pathogenesis, Diagnosis, and Treatment of Esophageal Cancer

Esophageal cancer is one of the most common malignancy in China with high mortality. Understanding pathogenesis and identifying early diagnosis biomarkers can significantly improve the prognosis of patients with esophageal cancer. Exosomes are small vesicular structures containing a variety of components (including DNA, RNA, and proteins) mediating cell-to-cell material exchange and signal communication. Growing evidences have shown that exosomes and its components are involved in growth, metastasis and angiogenesis in cancer, and could also be used as diagnostic and prognostic markers. In this review, we summarized recent progress to elucidate the significance of exosomes in the esophageal cancer progression, microenvironment remodeling, therapeutic resistance, and immunosuppression. We also discuss the utility of exosomes as diagnostic and prognostic biomarkers and therapeutic tool in esophageal cancer.

CEACAM Gene Family Mutations Associated With Inherited Breast Cancer Risk - A Comparative Oncology Approach to Discovery

Introduction

Recent studies comparing canine mammary tumors (CMTs) and human breast cancers have revealed remarkable tumor similarities, identifying shared expression profiles and acquired mutations. CMTs can also provide a model of inherited breast cancer susceptibility in humans; thus, we investigated breed-specific whole genome sequencing (WGS) data in search for novel CMT risk factors that could subsequently explain inherited breast cancer risk in humans.

Methods

WGS was carried out on five CMT-affected Gold Retrievers from a large pedigree of 18 CMT-affected dogs. Protein truncating variants (PTVs) detected in all five samples (within human orthlogs) were validated and then genotyped in the 13 remaining CMT-affected Golden Retrievers. Allele frequencies were compared to canine controls. Subsequently, human blood-derived exomes from The Cancer Genome Atlas breast cancer cases were analyzed and allele frequencies were compared to Exome Variant Server ethnic-matched controls.

Results

Carcinoembryonic Antigen-related Cell Adhesion Molecule 24 (CEACAM24) c.247dupG;p.(Val83Glyfs^∗48) was the only validated variant and had a frequency of 66.7% amongst the 18 Golden Retrievers with CMT. This was significant compared to the European Variation Archive (p-value 1.52 × 10^–8) and non-Golden Retriever American Kennel Club breeds (p-value 2.48 × 10^–5). With no direct ortholog of CEACAM24 in humans but high homology to all CEACAM gene family proteins, all human CEACAM genes were investigated for PTVs. A total of six and sixteen rare PTVs were identified in African and European American breast cancer cases, respectively. Single variant assessment revealed five PTVs associated with breast cancer risk. Gene-based aggregation analyses revealed that rare PTVs in CEACAM6, CEACAM7, and CEACAM8 are associated with European American breast cancer risk, and rare PTVs in CEACAM7 are associated with breast cancer risk in African Americans. Ultimately, rare PTVs in the entire CEACAM gene family are associated with breast cancer risk in both European and African Americans with respective p-values of 1.75 × 10^–13 and 1.87 × 10^–04.

Conclusion

This study reports the first association of inherited CEACAM mutations and breast cancer risk, and potentially implicates the whole gene family in genetic risk. Precisely how these mutations contribute to breast cancer needs to be determined; especially considering our current knowledge on the role that the CEACAM gene family plays in tumor development, progression, and metastasis.

Exosome-derived microRNA-433 inhibits tumorigenesis through incremental infiltration of CD4 and CD8 cells in non-small cell lung cancer

Tumor-derived exosomal microRNAs (miRNAs/miRs) serve a vital biological role in tumorigenesis and development, but the effects and underlying mechanisms remain unclear. To explore the impact of exosomal miR-433 in non-small cell lung cancer (NSCLC) and understand its mechanism of action in NSCLC progression, the present study isolated the exosomes from the plasma of patients with NSCLC after chemotherapy and found that miR-433 expression was lower in plasma of patients with resistant NSCLC compared with in plasma of patients with sensitive NSCLC and in normal serum. Additionally, miR-433 expression was markedly negatively associated with a large tumor size, distant metastasis, advanced TNM stage and a poor prognosis in patients with NSCLC. miR-433 inhibited tumor growth by blocking the cell cycle in vitro and in vivo, as well as by promoting apoptosis and T-cell infiltration in the tumor microenvironment. Additionally, miR-433 inhibited chemoresistance to cisplatin by regulating DNA damage. Moreover, miR-433 inactivated the WNT/β-catenin signaling pathway by targeting transmembrane p24 trafficking protein 5 in NSCLC. Overall, the current findings may provide a potential prognostic biomarker and therapeutic target for patients with NSCLC.

MiR-1539 and Its Potential Role as a Novel Biomarker for Colorectal Cancer

Purpose

We investigated microRNA (miR) 1539 as a potential biomarker for predicting the risk and pathobiological behavior of colorectal cancer (CRC).

Methods

Our strategy consisted of analyzing 100 serum samples from 51 CRC patients, 49 healthy controls (HCs), and another 56 CRC tissue and matched normal adjacent to tumor (NAT) samples. The relative expression levels of miR-1539 in exosomes, serum and tissues were detected and compared in the different groups, using reverse transcription-polymerase chain reaction (RT-qPCR). The diagnostic value and potential function of miR-1539 were investigated using clinicopathological data combined with bioinformatics analysis.

Results

MiR-1539 expression was significantly up-regulated in exosomes (p = 0.003) and cancer tissue (p < 0.001) from CRC patients. MiR-1539 expression levels in serum varied according to different tumor sites (right-sided vs. left-sided, p = 0.047; left-side CRC vs. HCs, p = 0.031). In terms of diagnostic efficacy, miR-1539 expression in exosomes may help distinguish CRC cases from HCs with a sensitivity of 92.2%, and miR-1539 expression in serum may improve the specificity to 96.6% for left-sided CRC diagnosis. When combined with clinicopathological data, serum miR-1539 levels were positively associated with vascular endothelial growth factor (VEGF) expression (p = 0.028), whilst levels in CRC tissue were positively associated with increased Ki-67 levels (p = 0.035). Poorer pathologic differentiation was potentially related to an increased tendency of miR-1539 expression in CRC tissue (p = 0.071). Based on our bioinformatics analysis, miR-1539 may have a significant mechanistic influence on CRC genesis and progression.

Conclusions

Circulating or tissue based miR-1539 may be used as a novel potential biomarker for CRC screening, and a predictor of poor clinicopathological behavior in tumors.

MicroRNA-210 targets FBXO31 to inhibit tumor progression and regulates the Wnt/β-catenin signaling pathway and EMT in esophageal squamous cell carcinoma

Evidence from previous studies showed that the dysregulation of microRNA (miR) is frequently associated with tumor progression. The aberrant miR‐210 expression has been identified in a variety of tumors. However, its biological roles in esophageal squamous cell carcinoma (ESCC) still need further elucidation. Thus, in the current study we explore the roles of miR‐210 in ESCC progression. The findings of our study reveal that miR‐210 is down‐regulated in ESCC, which indicates poor prognosis and aggressive tumor progression. Moreover, miR‐210 restoration was found to enhance ESCC viability, invasion, and migration abilities. F‐Box only protein 31 (FBXO31) was confirmed to be one of the targets of miR‐210 in ESCC cells. Results also revealed that miR‐210 played crucial roles in regulating ESCC cell epithelial‐mesenchymal transition (EMT) and Wnt/β‐catenin signaling. In conclusion, data show that miR‐210 serves as an anti‐ESCC miR via down‐regulation of FBXO31 and regulation of EMT and Wnt signaling, suggesting that the miR‐210/FBXO31 axis may function as promising therapeutic targets and effective prognostic markers for ESCC patients.

miR‐210 serves as an anti‐ESCC miR via down‐regulation of FBXO31 and regulation of EMT and Wnt signaling

miR-766-3p Targeting BCL9L Suppressed Tumorigenesis, Epithelial-Mesenchymal Transition, and Metastasis Through the β-Catenin Signaling Pathway in Osteosarcoma Cells

Accumulating evidence has indicated that abnormal microRNAs (miRNAs) serve critical roles in carcinogenesis and development of osteosarcoma (OS). The purpose of the present study was to elucidate the relationship between miR-766-3p and development of osteosarcoma and explore the potential mechanism. In this study, we found that miR-766-3p was the most downregulated miRNA by analyzing GSE65071 from the GEO database. miR-766-3p was lowly expressed in OS tissue samples and cells, and high miR-766-3p expression repressed the malignant level of OS, including cell proliferation, EMT, migration, and invasion in vitro and in vivo. B-Cell Lymphoma 9-Like Protein (BCL9L) was negatively associated with miR-766-3p expression in OS cells and tissue samples and was validated as the downstream target by luciferase reporter assay and western blotting. Rescue experiment indicated that BCL9L could restore the influence of miR-766-3p on OS cells. In addition, the β-Catenin/TCF-4 signal pathway was demonstrated to be related to the miR-766-3p/BCL9L axis. In summary, miR-766-3p, a negative regulator of BCL9L, plays the role of tumor metastasis suppressor via the β-catenin signaling pathway in the progression of OS.

The Value of Serum MicroRNA Expression Signature in Predicting Refractoriness to Bortezomib-Based Therapy in Multiple Myeloma Patients

Bortezomib is the first-in-class proteasome inhibitor, commonly used in the treatment of multiple myeloma (MM). The mechanisms underlying acquired bortezomib resistance in MM are poorly understood. Several cell-free miRNAs have been found to be aberrantly regulated in MM patients. The aim of this pilot study was to identify a blood-based miRNA signature that predicts bortezomib-based therapy efficacy in MM patients. Thirty MM patients treated with bortezomib-based regimens were studied, including 19 with refractory disease and 11 who were bortezomib sensitive. Serum miRNA expression patterns were identified with miRCURY LNA miRNA miRNome PCR Panels I+II (Exiqon/Qiagen). Univariate analysis found a total of 21 miRNAs to be differentially expressed in patients with MM according to bortezomib sensitivity. Multivariate logistic regression was created and allowed us to discriminate refractory from sensitive patients with a very high AUC of 0.95 (95%CI: 0.84-1.00); sensitivity, specificity and accuracy were estimated as 0.95, 0.91, and 0.93. The model used expression of 3 miRNAs: miR-215-5p, miR-181a-5p and miR-376c-3p. This study is the first to demonstrate that serum expression of several miRNAs differs between patients who are bortezomib refractory and those who are sensitive which may prove useful in studies aimed at overcoming drug resistance in MM treatment.

Serum exosomal microRNA-766-3p expression is associated with poor prognosis of esophageal squamous cell carcinoma

The aim was to analyze the association between exosomal microRNA (miR)‐766‐3p expression levels in serum and the prognosis of esophageal squamous cell carcinoma (ESCC). The serum global exosomal miRNA expression of ESCC patients was measured by microRNA microarray. Quantitative real‐time PCR was used to analyze the expression levels of candidate miRNAs in both serum and tissues from ESCC patients. Wilcoxon tests were applied to evaluate clinical characteristics and their association with serum levels of exosomal miR‐766‐3p. A Cox regression model was used to identify prognostic factors. The effects of miR‐766‐3p expression on cell migration and invasion were examined using Transwell assays, and CCK‐8 assays were carried out to measure cell proliferation. The TNM stage was associated with high serum exosomal miR‐766‐3p levels of ESCC patients (P = .030). Higher serum exosomal miR‐766‐3p expression levels were associated with poor prognosis (for overall survival, hazard ratio [HR] [95% confidence interval (CI)], 2.21 [1.00, 4.87]; for disease‐free survival, HR [95% CI], 2.15 [1.01, 4.59]). However, we found no association between the expression of miR‐766‐3p in tissue and ESCC prognosis. In vitro results showed that miR‐766‐3p promotes cell migration and invasion, but not cell proliferation. By using dual‐luciferase reporter assay, HOXA13 was confirmed as a direct target gene of miR‐766‐3p. The ESCC patients with highly expressed serum exosomal miR‐766‐3p had a significantly worse survival. Therefore, serum exosomal miR‐766‐3p could serve as a prognostic marker for the assessment of ESCC.