The Potential Diagnostic Value of Exosomal Long Noncoding RNAs in Solid Tumors: A Meta-Analysis and Systematic Review

Evolving Role of Exosomes in Plastic and Reconstructive Surgery and Dermatology

Exosomes, or extracellular vesicles, represent the latest cell-free addition to the regenerative medicine toolkit. In vitro preclinical studies have demonstrated the safety and efficacy of exosomes, which vary based on source and biomanufacturing, for a myriad of potential therapeutic applications relevant to skin and soft tissue reconstruction. Primary search was performed in September 2021 on the MEDLINE database via PubMed and Ovid, with focus on articles about therapeutic application of exosomes or extracellular vesicles. In total, 130 articles met criteria for applicability, including early-stage clinical trials, preclinical research studies with in vivo application, and articles applicable to plastic and reconstructive surgery and dermatology. Most studies used animal models of human disease processes, using either animal donor cells to isolate exosomes, or human donor cells in animal models. Exosome technology has catapulted as an acellular therapeutic vehicle with off-the-shelf accessibility. These features eliminate prior threshold for broad adoption of regenerative cell-based therapies into surgical and medical practice. To date, there are no exosome products approved by the US Food and Drug Administration. This review highlights exosomes as the new frontier in regenerative medicine and outlines its preclinical therapeutic applications for cutaneous repair and restoration.

Diagnostic Accuracy of Exosomal Long Noncoding RNAs in Diagnosis of NSCLC: A Meta-Analysis

PURPOSE

Globally, non-small cell lung cancer (NSCLC) is the primary cause of cancer-related mortality, both early and accurate diagnosis are essential for effective treatment and improved patient outcomes. Exosomal noncoding RNAs (ncRNAs) have emerged as promising biomarkers for NSCLC diagnosis. This meta-analysis aims to assess the diagnostic accuracy of exosomal long noncoding RNAs (lncRNAs) for diagnosing NSCLC.

METHODS

A comprehensive literature search was conducted to identify relevant studies that assessed the diagnostic performance of exosomal lncRNAs in NSCLC. Quality assessment and data extraction were performed independently by two reviewers. Pooled sensitivity, specificity, and other relevant diagnostic parameters were calculated using a bivariate random-effects model. Subgroup analyses and meta-regression were conducted to explore potential sources of heterogeneity.

RESULTS

Sixteen studies, comprising 1843 NSCLC cases and 1298 controls, were included in this meta-analysis. The pooled sensitivity and specificity of nine exosomal lncRNAs for diagnosing NSCLC were 0.74 [95% confidence interval (CI) 0.69-0.79] and 0.78 (95% CI 0.68-0.85). The pooled area under the receiver operating characteristic curve (AUC) for fifteen lncRNAs was 0.80 (95% CI 0.768-0.831). Meta-regression could not find any source for interstudy heterogeneity.

CONCLUSION

Exosomal lncRNAs, particularly AL139294.1, GAS5, LUCAT1, and SOX2-OT, have excellent diagnostic accuracy and promising diagnostic potential in NSCLC. Therefore, they can be used as diagnostic tools for early detection of NSCLC.

Diagnostic value of exosomal noncoding RNA in lung cancer: a meta-analysis

Background

Lung cancer is one of the most dangerous cancers in the world. Most lung cancer patients are diagnosed in the middle and later stages, which can lead to poor survival rates. The development of lung cancer is often accompanied by abnormal expression of exosomal non-coding RNAs, which means that they have the potential to serve as noninvasive novel molecular markers for lung cancer diagnosis.

Methods

For this study, we conducted a comprehensive literature search in PubMed, Web of science, Science direct, Embase, Cochrane, and Medline databases, and by reviewing published literature, The diagnostic capacity of exosomal microRNAs (miRNAs), long-chain non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) for lung cancer was evaluated. Functional enrichment analysis of miRNA target genes was performed.

Results

The study included 41 papers, a total of 68 studies. More than 60 miRNAs, 9 lncRNAs and 14 circRNAs were involved. The combined sensitivity and specificity were 0.83(95%CI, 0.80~0.86) and 0.83(95% CI,0.79~0.87); 0.71(95% CI,0.68~0.74) and 0.79(95%CI, 0.75~0.82); 0.79(95%CI,0.67~0.87) and 0.81(95%CI,0.74~0.86), and constructed overall subject operating characteristic curves with the summarized area under the curve values of 0.90, 0.82, and 0.86.

Conclusion

Our study shows that exosomes miRNAs, lncRNAs and circRNAs are effective in the diagnosis of lung cancer, providing evidence for studies related to novel lung cancer diagnostic markers.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42023457087.

Diagnostic accuracy of circulating exosomal circRNAs in malignances: A meta-analysis and systematic review

BACKGROUND

Pathogenesis of malignant tumors are often accompanied by aberrant expression of circular RNAs (circRNAs), indicating the potential diagnostic value of circRNAs in tumors. CircRNAs have been found to be enriched, stable and ubiquitous in serum and plasma exosomes. The study aims at evaluating the diagnostic performance of circulating (plasma and serum) exosomal circRNA in different types of cancer by synthesis of published data.

METHODS

A comprehensive literature search was conducted in PubMed, Embase, Medline and the Web of Science databases to identify potentially eligible studies published before April 2021. We conducted the meta-analysis following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations.

RESULTS

Eleven articles comprising 21 studies were included, and a total of 1609 cases and 1498 controls were evaluated. Six types of cancer were involved in these studies, including lung cancer, hepatocellular carcinoma, colorectal cancer, gastric cancer, multiple myeloma and osteosarcoma. The pooled sensitivity and specificity were 0.72 (95% confidence interval [CI], 0.62-0.81) and 0.83 (95% CI, 0.78-0.88), respectively. Summary receiver operating characteristic curve was constructed and the pooled value of area under curve was 0.86 (95% CI, 0.83-0.89), indicating a favorable diagnostic efficacy of circulating exosomal circRNAs in malignancies.

CONCLUSIONS

In conclusion, our study evaluated the diagnostic power of circulating exosomal circRNAs in 6 types of cancer by synthesis of published data comprising 21 studies from eleven articles. The pooled analysis provided the evidence supporting circulating exosomal circRNAs as a promising noninvasive diagnostic biomarkers for malignancies.

Extracellular Vesicles in Breast Cancer: From Biology and Function to Clinical Diagnosis and Therapeutic Management

Breast cancer (BC) is the first worldwide most frequent cancer in both sexes and the most commonly diagnosed in females. Although BC mortality has been thoroughly declining over the past decades, there are still considerable differences between women diagnosed with early BC and when metastatic BC is diagnosed. BC treatment choice is widely dependent on precise histological and molecular characterization. However, recurrence or distant metastasis still occurs even with the most recent efficient therapies. Thus, a better understanding of the different factors underlying tumor escape is mainly mandatory. Among the leading candidates is the continuous interplay between tumor cells and their microenvironment, where extracellular vesicles play a significant role. Among extracellular vesicles, smaller ones, also called exosomes, can carry biomolecules, such as lipids, proteins, and nucleic acids, and generate signal transmission through an intercellular transfer of their content. This mechanism allows tumor cells to recruit and modify the adjacent and systemic microenvironment to support further invasion and dissemination. By reciprocity, stromal cells can also use exosomes to profoundly modify tumor cell behavior. This review intends to cover the most recent literature on the role of extracellular vesicle production in normal and cancerous breast tissues. Specific attention is paid to the use of extracellular vesicles for early BC diagnosis, follow-up, and prognosis because exosomes are actually under the spotlight of researchers as a high-potential source of liquid biopsies. Extracellular vesicles in BC treatment as new targets for therapy or efficient nanovectors to drive drug delivery are also summarized.

Advances in early detection methods for solid tumors

During the last decade, non-invasive methods such as liquid biopsy have slowly replaced traditional imaging and invasive pathological methods used to diagnose and monitor cancer. Improvements in the available detection methods have enabled the early screening and diagnosis of solid tumors. In addition, advances in early detection methods have made the continuous monitoring of tumor progression using repeat sampling possible. Previously, the focus of liquid biopsy techniques included the following: 1) the isolation of circulating tumor cells, circulating tumor DNA, and extracellular tumor vesicles from solid tumor cells in the patient's blood; in addition to 2) analyzing genomic and proteomic data contained within the isolates. Recently, there has been a rapid devolvement in the techniques used to isolate and analyze molecular markers. This rapid evolvement in detection techniques improves their accuracy, especially when few samples are available. In addition, there is a tremendous expansion in the acquisition of samples and targets for testing; solid tumors can be detected from blood and other body fluids. Test objects have also expanded from samples taken directly from cancer to include indirect objects affected in cancer development. Liquid biopsy technology has limitations. Even so, this detection technique is the key to a new phase of oncogenetics. This review aims to provide an overview of the current advances in liquid biopsy marker selection, isolation, and detection methods for solid tumors. The advantages and disadvantages of liquid biopsy technology will also be explored.

Gastric cancer cell-derived extracellular vesicles elevate E2F7 expression and activate the MAPK/ERK signaling to promote peritoneal metastasis through the delivery of SNHG12

Cancer cell-derived extracellular vesicles (EVs) have extensive application in the formation of their environment, including metastasis. This study explored the ability of gastric cancer (GC) cell-derived EVs-mediated microRNA-129-5p/E2F transcription factor 7/mitogen-activated protein kinase/extracellular regulated protein kinase (miR-129-5p/E2F7/MAPK/ERK) axis to affect the peritoneal metastasis of GC by delivering lncRNA small nucleolar RNA host gene 12 (SNHG12). EV-derived lncRNA and SNHG12/miR-129-5p/E2F7 network were determined by bioinformatics analysis. The regulatory relationship among SNHG12, miR-129-5p, and E2F7 was verified using a combination of dual-luciferase reporter gene, RNA immunoprecipitation, and RNA pull-down assays. The SNHG12, miR-129-5p, and E2F7 expression was measured by RT-qPCR. After GC cell-derived EVs were isolated and co-cultured with human peritoneal mesothelial cells (HPMCs), the uptake of EVs by HPMCs was observed under laser scanning confocal microscopy. Cell viability and apoptosis were examined using cell counting kit-8 and flow cytometry, respectively. Western blot analysis was performed to measure the mesothelial–mesenchymal transition (MMT)-related protein expression. The pathological and morphological characteristics of metastatic tumors in nude mice were observed by hematoxylin–eosin staining. A high SNHG12 expression was correlated with the poor prognosis of patients with GC. GC-derived EVs led to increased HPMC apoptosis and MMT by transferring SNHG12, whereas the knockdown of SNHG12 annulled the aforementioned results. SNHG12 sponged miR-129-5p to boost E2F7 expression and activate the MAPK/ERK signaling, thus inducing HPMC apoptosis and MMT. In vivo experiments further verified that EVs derived from GC cells promoted peritoneal metastasis in nude mice. GC cell-derived EVs elevated the E2F7 expression and activated the MAPK/ERK signaling to promote peritoneal metastasis through the delivery of SNHG12.

Liquid biopsy: a step closer to transform diagnosis, prognosis and future of cancer treatments

Over the past decade, invasive techniques for diagnosing and monitoring cancers are slowly being replaced by non-invasive methods such as liquid biopsy. Liquid biopsies have drastically revolutionized the field of clinical oncology, offering ease in tumor sampling, continuous monitoring by repeated sampling, devising personalized therapeutic regimens, and screening for therapeutic resistance. Liquid biopsies consist of isolating tumor-derived entities like circulating tumor cells, circulating tumor DNA, tumor extracellular vesicles, etc., present in the body fluids of patients with cancer, followed by an analysis of genomic and proteomic data contained within them. Methods for isolation and analysis of liquid biopsies have rapidly evolved over the past few years as described in the review, thus providing greater details about tumor characteristics such as tumor progression, tumor staging, heterogeneity, gene mutations, and clonal evolution, etc. Liquid biopsies from cancer patients have opened up newer avenues in detection and continuous monitoring, treatment based on precision medicine, and screening of markers for therapeutic resistance. Though the technology of liquid biopsies is still evolving, its non-invasive nature promises to open new eras in clinical oncology. The purpose of this review is to provide an overview of the current methodologies involved in liquid biopsies and their application in isolating tumor markers for detection, prognosis, and monitoring cancer treatment outcomes.

Dental pulp stem cell-derived small extracellular vesicle in irradiation-induced senescence

Small extracellular vesicles (sEV) facilitate signaling molecule transfer among cells. We examined the therapeutic efficacy of human dental pulp stem cell-derived sEV (hDPSC-sEV) against cellular senescence in an irradiated-submandibular gland mouse model. Seven-week-old mice were exposed to 25 Gy radiation and randomly assigned to control, phosphate-buffered saline (PBS), or hDPSC-sEV groups. At 18 days post-irradiation, saliva production was measured; histological and reverse transcription-quantitative PCR analyses of the submandibular glands were performed. The salivary flow rate did not differ significantly between the PBS and hDPSC-sEV groups. AQP5-expressing acinar cell numbers and AQP5 expression levels in the submandibular glands were higher in the hDPSC-sEV group than in the other groups. Furthermore, compared with non-irradiated mice, mice in the 25 Gy + PBS group showed a high senescence-associated-β-galactosidase-positive cell number and upregulated senescence-related gene (p16^INK4a, p19^Arf, p21) and senescence-associated secretory phenotypic factor (MMP3, IL-6, PAI-1, NF-κB, and TGF-β) expression, all of which were downregulated in the hDPSC-sEV group. Superoxide dismutase levels were lower in the PBS group than in the hDPSC-sEV group. In summary, hDPSC-sEV reduced inflammatory cytokine and senescence-related gene expression and reversed oxidative stress in submandibular cells, thereby preventing irradiation-induced cellular senescence. Based on these results, we hope to contribute to the development of innovative treatment methods for salivary gland dysfunction that develops after radiotherapy for head and neck cancer.

Exosomes in Lung Cancer: Actors and Heralds of Tumor Development

Lung cancer is a leading cause of cancer-related death worldwide and in most cases, diagnosis is reached when the tumor has already spread and prognosis is quite poor. For that reason, the research for new biomarkers that could improve early diagnosis and its management is essential. Exosomes are microvesicles actively secreted by cells, especially by tumor cells, hauling molecules that mimic molecules of the producing cells. There are multiple methods for exosome isolation and analysis, although not standardized, and cancer exosomes from biological fluids are especially difficult to study. Exosomes' cargo proteins, RNA, and DNA participate in the communication between cells, favoring lung cancer development by delivering signals for growth, metastasis, epithelial mesenchymal transition, angiogenesis, immunosuppression and even drug resistance. Exosome analysis can be useful as a type of liquid biopsy in the diagnosis, prognosis and follow-up of lung cancer. In this review, we will discuss recent advances in the role of exosomes in lung cancer and their utility as liquid biopsy, with special attention to isolating methods.

Emerging Role of Exosomes in Liquid Biopsy for Monitoring Prostate Cancer Invasion and Metastasis

Prostate cancer (PCa) is the most common solid tumor in men. While patients with local PCa have better prognostic survival, patients with metastatic PCa have relatively high mortality rates. Existing diagnostic methods for PCa rely on tissue biopsy and blood prostate-specific antigen (PSA) detection; however, the PSA test does not detect aggressive PCa. Liquid biopsy is a promising technique to overcome tumor heterogeneity in diagnosis, provide more comprehensive information, and track tumor progression over time, allowing for the development of treatment options at all stages of PCa. Exosomes containing proteins and nucleic acids are potential sources of tumor biomarkers. Accumulating evidence indicates that exosomes play important roles in cell communication and tumor progression and are suitable for monitoring PCa progression and metastasis. In this review, we summarize recent advances in the use of exosomal proteins and miRNAs as biomarkers for monitoring PCa invasion and metastasis and discuss their feasibility in clinical diagnosis.