Urine miR-21-5p as a potential non-invasive biomarker for gastric cancer

Potential diagnostic, prognostic, and predictive biomarkers of gastric cancer

Background

Gastric cancer (GC), a malignant epithelial tumor, is the fourth leading cause of cancer-related death worldwide. Therapeutic strategies for GC, despite the biggest challenges, can significantly improve survival rates through early detection and effective screening methods.

Aim

To provide brief information on the necessity of multiple specific diagnostic, prognostic, and predictive markers for GC.

Methods

This review was conducted using a variety of search engines, including PubMed Central, Scopus, Web of Science, Google Scholar, and others.

Results

Some potential biomarkers that provide essential information include circulating tumor cells (CTCs), DNA methylation, claudin 18.2, fibroblast growth factor receptor 2 (FGFR2), long noncoding RNAs (lncRNAs), cell-free DNA (cfDNA), microRNAs, and serum pepsinogens.

Conclusion

Multiple tumor markers are essential for screening, tumor identification, staging, prognostic assessment, and monitoring recurrence after therapy due to the absence of a single tumor indicator for diagnosing, prognosticating, and predicting GC.

Biomarker discovery and validation for gastrointestinal tumors: A comprehensive review of colorectal, gastric, and liver cancers

Gastrointestinal (GI) malignancies, encompassing gastric, hepatic, colonic, and rectal cancers, are prevalent forms of cancer globally and contribute substantially to cancer-related mortality. Although there have been improvements in methods for diagnosing and treating GI cancers, the chances of survival for these types of cancers are still extremely low. According to the World Cancer Research International Fund's most recent figures, stomach cancer was responsible for roughly one million deaths worldwide in 2020. This emphasizes the importance of developing more effective tools for detecting, diagnosing, and predicting the outcome of these cancers at an early stage. Biomarkers, quantitative indications of biological processes or disease states, have emerged as promising techniques for enhancing the diagnosis and prognosis of GI malignancies. Recently, there has been a considerable endeavor to discover and authenticate biomarkers for various GI cancers by the utilization of diverse methodologies, including genomics, proteomics, and metabolomics. This review provides a thorough examination of the current state of biomarker research in the field of gastrointestinal malignancies, with a specific emphasis on colorectal, stomach, and liver cancers. A thorough literature search was performed on prominent databases such as PubMed, Scopus, and Web of Science to find pertinent papers published until November, 2023 for the purpose of compiling this review. The diverse categories of biomarkers, encompassing genetic, epigenetic, and protein-based biomarkers, and their potential utility in the fields of diagnosis, prognosis, and treatment selection, are explored. Recent progress in identifying and confirming biomarkers, as well as the obstacles that persist in employing biomarkers in clinical settings are emphasized. The utilization of biomarkers in GI cancers has significant potential in enhancing patient outcomes. Ongoing research is expected to uncover more efficient biomarkers for the diagnosis and prognosis of these cancers.

The use of biological fluids in microfluidic paper-based analytical devices (μPADs): Recent advances, challenges and future perspectives

The use of microfluidic paper-based analytical devices (μPADs) for aiding medical diagnosis is a growing trend in the literature mainly due to their low cost, easy use, simple manufacturing, and great potential for application in low-resource settings. Many important biomarkers (proteins, ions, lipids, hormones, DNA, RNA, drugs, whole cells, and more) and biofluids are available for precise detection and diagnosis. We have reviewed the advances μPADs in medical diagnostics have achieved in the last few years, focusing on the most common human biofluids (whole blood/plasma, sweat, urine, tears, and saliva). The challenges of detecting specific biomarkers in each sample are discussed, along with innovative techniques that overcome such limitations. Finally, the difficulties of commercializing μPADs are considered, and future trends are presented, including wearable devices and integrating multiple steps in a single platform.

Bone Mesenchymal Stem Cell-Derived Small Extracellular Vesicles Ameliorated Lipopolysaccharide-Induced Lung Injury Via the miR-21-5p/PCSK6 Pathway

Acute lung injury (ALI) is a life-threatening disease that currently lacks a cure. Although stem cell-derived small extracellular vesicles (sEVs) have shown promising effects in the treatment of ALI, their underlying mechanisms and responsible components have yet to be identified. Proprotein convertase subtilisin/kexin type 6 (PCSK6) is a gene involved in inflammation and a potential target of miR-21-5p, a microRNA enriched in stem cell-derived sEVs. The current study investigated the role of PCSK6 in lipopolysaccharide (LPS)-induced ALI and its interaction with miR-21-5p. Notably, our results showed that PCSK6 expression was positively correlated with LPS stimulation. Knockdown of PCSK6 ameliorated LPS-induced inhibition of proliferation and upregulation of permeability in human BEAS-2B cells, whereas PCSK6 overexpression displayed the opposite effects. BEAS-2B cells were able to actively internalize the cocultured bone mesenchymal stem cell (MSC)-derived sEVs (BMSC-sEVs), which alleviated the cell damage caused by LPS. Overexpressing PCSK6, however, eliminated the therapeutic effects of BMSC-sEV coculture. Mechanistically, BMSC-sEVs inhibited PCSK6 expression via the delivery of miR-21-5p, which is directly bound to the PCSK6 gene. Our work provides evidence for the role of PCSK6 in LPS-induced ALI and identified miR-21-5p as a component of BMSC-derived sEVs that suppressed PCSK6 expression and ameliorated LPS-induced cell damage. These results reveal a novel molecular mechanism for ALI pathogenesis and highlight the therapeutic potential of using sEVs released by stem cells to deliver miR-21-5p for ALI treatment.

Comparison of Serum and Urine as Sources of miRNA Markers for the Detection of Ovarian Cancer

Ovarian cancer is the second most fatal gynecological cancer. Early detection, which could be achieved through widespread screening, has not yet had an impact on mortality. The aim of our pilot study was to investigate the expression of miRNAs analyzed by a human miRNA microarray chip in urine and serum of patients with ovarian cancer. We analyzed three serum and three urine samples from healthy donors and five serum and five urine samples from patients with ovarian cancer taken at first diagnosis, before any treatment. We selected the seven miRNAs with the highest expression fold change in the microarray chip (cancer vs. control) in urine and serum, for validation by qPCR. We were able to validate two of the seven miRNAs in serum. In contrast to these findings, we were able to validate all of the top seven miRNAs identified in urine using qPCR. The top seven miRNAs in urine identified by microarray chip showed significantly greater differences in expression between patients with ovarian cancer and healthy donors compared to serum. Based on our finding, we can suggest that urine as a biomaterial is more suitable than serum for miRNA profiling by microarray chip in the search for new biomarkers in ovarian cancer.

Urine biomarkers in cancer detection: A systematic review of preanalytical parameters and applied methods

The aim of this review was to explore the status of urine sampling as a liquid biopsy for noninvasive cancer research by reviewing used preanalytical parameters and protocols. We searched two main health sciences databases, PubMed and Web of Science. From all eligible publications (2010-2022), information was extracted regarding: (a) study population characteristics, (b) cancer type, (c) urine preanalytics, (d) analyte class, (e) isolation method, (f) detection method, (g) comparator used, (h) biomarker type, (i) conclusion and (j) sensitivity and specificity. The search query identified 7835 records, of which 924 unique publications remained after screening the title, abstract and full text. Our analysis demonstrated that many publications did not report information about the preanalytical parameters of their urine samples, even though several other studies have shown the importance of standardization of sample handling. Interestingly, it was noted that urine is used for many cancer types and not just cancers originating from the urogenital tract. Many different types of relevant analytes have been shown to be found in urine. Additionally, future considerations and recommendations are discussed: (a) the heterogeneous nature of urine, (b) the need for standardized practice protocols and (c) the road toward the clinic. Urine is an emerging liquid biopsy with broad applicability in different analytes and several cancer types. However, standard practice protocols for sample handling and processing would help to elaborate the clinical utility of urine in cancer research, detection and disease monitoring.

MiR-21-5p promotes sorafenib resistance and hepatocellular carcinoma progression by regulating SIRT7 ubiquitination through USP24

OBJECTIVE

To validate the mechanism by which miR-21-5p mediates autophagy in drug-resistant cells in hepatocellular carcinoma (HCC), aggravating sorafenib resistance and progression of HCC.

METHODS

HCC cells were treated with sorafenib to establish sorafenib-resistant cells, and nude mice were subcutaneously injected with hepatoma cells to establish animal models. RT-qPCR was used to determine the level of miR-21-5p, and Western blotting was used to determine the level of related proteins. Cell apoptosis, cell migration, the level of LC3 were accessed. Immunohistochemical staining was used for detection of Ki-67 and LC3. A dual-luciferase reporter assay certified that miR-21-5p targets USP42, and a co-immunoprecipitation assay validated the mutual effect between USP24 and SIRT7.

RESULTS

miR-21-5p and USP42 were highly expressed in HCC tissue and cells. Inhibition of miR-21-5p or knockdown of USP42 inhibited cell proliferation and cell migration, upregulated the level of E-cadherin, and downregulated the level of vimentin, fibronectin and N-cadherin. Overexpression of miR-21-5p reversed the knockdown of USP42. Inhibition of miR-21-5p downregulated the ubiquitination level of SIRT7, downregulated the levels of LC3II/I ratio and Beclin1, and upregulated the expression of p62. The tumor size in the miR-21-5p inhibitor group was smaller, and Ki-67 and LC3 in tumor tissue were reduced, while the overexpression of USP42 reversed the effect of the miR-21-5p inhibitor.

CONCLUSION

miR-21-5p promotes deterioration and sorafenib resistance in hepatocellular carcinoma by upregulating autophagy levels. Knockdown of miR-21-5p inhibits the development of sorafenib-resistant tumors by USP24-mediated SIRT7 ubiquitination.

MicroRNA-21: A critical underestimated molecule in diabetic retinopathy

Diabetes mellitus (DM) has grown in attention in recent years as a result of its debilitating complications and chronic disabilities. Diabetic retinopathy (DR) is a chronic microvascular complication of DM and is considered as the primary reason for blindness in adults. Early diagnosis of diabetes complications along with targeted therapy options are critical in avoiding morbidity and mortality associated with complications of diabetes. miR-21 is an important and widely studied non-coding-RNA (ncRNA) with considerable roles in various pathologic conditions including diabetic complications. miR-21 is one of the most elevated miRNAs in response to hyperglycemia and its role in angiogenesis is a major culprit of a wide range of disorders including DR. The main role of miR-21 in DR pathophysiology is believed to be through regulating angiogenesis in retina. This article aims to outline miR-21 biogenesis and distribution in human body along with discussions about its role in DR pathogenesis and its biomarker value in order to facilitate understanding of the new characteristics of miR-21 in DR management.

Pre-clinical and clinical importance of miR-21 in human cancers: Tumorigenesis, therapy response, delivery approaches and targeting agents

The field of non-coding RNA (ncRNA) has made significant progress in understanding the pathogenesis of diseases and has broadened our knowledge towards their targeting, especially in cancer therapy. ncRNAs are a large family of RNAs with microRNAs (miRNAs) being one kind of endogenous RNA which lack encoded proteins. By now, miRNAs have been well-coined in pathogenesis and development of cancer. The current review focuses on the role of miR-21 in cancers and its association with tumor progression. miR-21 has both oncogenic and onco-suppressor functions and most of the experiments are in agreement with the tumor-promoting function of this miRNA. miR-21 primarily decreases PTEN expression to induce PI3K/Akt signaling in cancer progression. Overexpression of miR-21 inhibits apoptosis and is vital for inducing pro-survival autophagy. miR-21 is vital for metabolic reprogramming and can induce glycolysis to enhance tumor progression. miR-21 stimulates EMT mechanisms and increases expression of MMP-2 and MMP-9 thereby elevating tumor metastasis. miR-21 is a target of anti-cancer agents such as curcumin and curcumol and its down-regulation impairs tumor progression. Upregulation of miR-21 results in cancer resistance to chemotherapy and radiotherapy. Increasing evidence has revealed the role of miR-21 as a biomarker as it is present in both the serum and exosomes making them beneficial biomarkers for non-invasive diagnosis of cancer.

Key methodological challenges in detecting circulating miRNAs in different biofluids

The technological advancement in diagnostic techniques has immensely improved the capability of predicting disease progression. Yet, there is a great interest in developing newer biomarkers that can enhance disease risk prediction thereby minimising the associated morbidity and mortality. Circulating miRNAs, a non-coding RNA molecule, are critical regulators in the pathophysiology of various complex multifactorial diseases. In recent years, circulating miRNAs have been enormously studied and are considered as an emerging biomarker due to their easy accessibility, stability, and detection by sequence-specific amplification methods. However, there is a distinct lack of consensus regarding the preanalytical factors such as preferred sample selection, methodological aspects, etc that may independently or together influence the detection of circulating miRNAs resulting in erroneous expression profiles. Therefore, the present review makes an attempt to highlight the various pre-analytical and analytical factors that can potentially influence the circulating miRNA levels. Literature on circulating miRNA's stability, processing and quantitation in different biofluids along with the effect of various controllable and uncontrollable factors influencing circulating miRNA expression have been summarised in the current review.

Gastric cancer detection by non-blood-based liquid biopsies: A systematic review looking into the last decade of research

Gastric cancer (GC) screening is arguable in most Western countries. Liquid biopsies are a great promise to answer the unmet need for less invasive diagnostic biomarkers in GC. Thus, we aimed at systematically reviewing the current knowledge on liquid biopsy-based biomarkers in GC screening. A systematic search on PubMed/MEDLINE and Scopus databases was performed on published articles reporting the use of non-blood specimen (saliva, gastric juice [GJ], urine and stool) on GC diagnosis. 3208 records were retrieved by June 2022. After removal of duplicate records, 2379 abstracts were screened, and 84 full texts included in this systematic review. More than 90% of studies were reported on Asian populations. Overall, 9 studies explored stool-, 12 saliva-, and 29 urine-derived biomarkers for GC detection. Additionally, 37 studies, representing the majority, analyzed GJ, focusing on nucleic acid molecules. Several miRNAs and lncRNA molecules have been associated with GC risk, particularly miR-21 (area under the curve [AUC] = 0.97, 95% CI: 0.94-1.00). Considering salivary biomarkers, the best described model in validation sets included the soybean agglutinin and Vicia villosa agglutinin lectins (AUC = 0.89, 95% CI: 0.80-0.99). Most studies in urine carried out metabolomic approaches, with two discriminatory models presenting AUC values superior to 0.97. This systematic review emphasizes the potential role of non-blood-based biomarkers, although further validation, particularly in Western countries, is mandatory, namely for non-invasive screening and/or monitoring, as well as the use of GJ as a tool to enhance upper gastrointestinal endoscopy accuracy.

Liquid biopsy in gastric cancer: predictive and prognostic biomarkers

Gastric cancer (GC) is a high-incidence cancer worldwide. Most patients are diagnosed at an advanced stage, by which time they have limited treatment options and poor prognosis. Early diagnosis and precise treatment are important. In the past few years, emerging research has been conducted on the use of non-invasive liquid biopsy, with its advantages of minimal invasiveness and repeated sampling, to monitor tumor occurrence and recurrence in real time and to evaluate prognosis and treatment response. Many studies have demonstrated the potential of liquid biopsy in GC, and the detection of circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), circulating free DNA (cfDNA), and exosomes has achieved gratifying results. In this review, we summarize evolving technologies for and information regarding liquid biopsy, the most recently discovered GC liquid biopsy biomarkers, and ongoing clinical trials and discuss the challenges and application prospects of liquid biopsy in GC.

Novel biomarkers of microRNAs in gastric cancer; an overview from diagnosis to treatment

The fourth frequent disease in the world and the second cause of cancer-related death is gastric cancer (GC). In this way, over 80% of diagnoses are made in the middle to advanced degrees of the disease, underscoring the requirement for innovative biomarkers that can be identified quickly. Meaningly, biomarkers that can complement endoscopic diagnosis and be used to detect patients with a high risk of GC are desperately needed. These biomarkers will allow for the accurate prediction of therapy response and prognosis in GC patients, as well as the development of an optimal treatment strategy for each individual. Conspicoiusly, microRNAs (miRNAs) and small noncoding RNA regulates the expression of target mRNA and thereby modifies critical biological mechanisms. According to the data, abnormally miRNAs expression in GC is linked to tumor growth, carcinogenesis, aggression and distant metastasis. Importantly, miRNA expression patterns and next-generation sequencing (NGS) can also be applied to analyze kinds of tissues and cancers. Given the high death rates and poor prognosis of GC, and the absence of a clinical diagnostic factor that is adequately sensitive to GC, research into novel sensitive and specific markers for GC diagnosis is critical. In this review,we evaluate the latest research findings that suggest the feasibility and clinical utility of miRNAs in GC.

miR-21-5p is a Biomarker for Predicting Prognosis of Lung Adenocarcinoma by Regulating PIK3R1 Expression

Background

Lung cancer (LUCA) is one of the most prevalent human malignancies, and the leading cause of cancer-related deaths worldwide. Previous reports have shown that miR-21-5p plays a vital role in development of various tumors. Here, we explored the relationship between miR-21-5p/PIK3R1 axis and prognosis of patients with lung adenocarcinoma (LUAD).

Methods

MiRNAseq data, deposited in The Cancer Genome Atlas (TCGA) database, was downloaded and used to determine patterns of miR-21-5p expression in both LUAD and normal lung tissues. Statistical analyses and data visualization were performed using dbDEMC v3.0 platform, starBase v3.0 database and packages implemented in R software. Next, we employed TargetScan Human, miRDB and DIANA Tools databases to predict miR-21-5p target genes, then analyzed their expression patterns as well as prognostic value in LUAD.

Findings

Most human cancers overexpressed miR-21-5p. Specifically, miR-21-5p was significantly upregulated in LUAD tissues relative to normal lung tissues (P < 0.001), and this high expression was significantly correlated with poor patient prognosis (hazard ratio [HR]=1.45, P = 0.014). PIK3R1 was predicted as a miR-21-5p target gene, and both were negatively correlated (r=-0.218, P < 0.01). Notably, PIK3R1 was significantly downregulated in LUAD, relative to normal lung tissues (P < 0.01), with its overexpression significantly associated with poor prognosis of LUAD patients (HR = 0.62, P = 0.0014).

Conclusion

miR-21-5p is a potential prognostic biomarker for LUAD patients. Moreover, it might be playing a role in LUAD progression by regulating PIK3R1 expression.

Clinical Applications of Liquid Biopsy in Gastric Cancer

Liquid biopsy represents an exciting new area in the field of cancer diagnosis and management, offering a less invasive and more convenient approach to obtain a time-point image of the tumor burden and its genomic profile. Samples collected from several body fluids, mostly blood, can be used to gain access to circulating tumor cells and DNA, non-coding RNAs, microRNAs, and exosomes, at any moment, offering a dynamic picture of the tumor. For patients with GC, the use of blood-based biopsies may be particularly beneficial since tissue biopsies are difficult to obtain and cause real distress to the patient. With advantages such as repeatability and minimal invasion, it is no wonder that the field of liquid biopsy has received tremendous attention. However, the abundance of studies, involving a wide range of assays with different principles, prevented for the moment the reproducibility of the results and therefore the translation into the clinic of liquid biopsy. In this review, we present the latest technical development and data on circulating biomarkers available through liquid biopsy in gastric cancer with an emphasis on their clinical utility in areas such as cancer screening, prognostic stratification, and therapeutic management.

Beyond liquid biopsy: Toward non-invasive assays for distanced cancer diagnostics in pandemics

Liquid biopsy technologies have seen a significant improvement in the last decade, offering the possibility of reliable analysis and diagnosis from several biological fluids. The use of these technologies can overcome the limits of standard clinical methods, related to invasiveness and poor patient compliance. Along with this there are now mature examples of lab-on-chips (LOC) which are available and could be an emerging and breakthrough technology for the present and near-future clinical demands that provide sample treatment, reagent addition and analysis in a sample-in/answer-out approach. The possibility of combining non-invasive liquid biopsy and LOC technologies could greatly assist in the current need for minimizing exposure and transmission risks. The recent and ongoing pandemic outbreak of SARS-CoV-2, indeed, has heavily influenced all aspects of life worldwide. Ordinary tasks have been forced to switch from “in presence” to “distanced”, limiting the possibilities for a large number of activities in all fields of life outside of the home. Unfortunately, one of the settings in which physical distancing has assumed noteworthy consequences is the screening, diagnosis and follow-up of diseases.

In this review, we analyse biological fluids that are easily collected without the intervention of specialized personnel and the possibility that they may be used -or not-for innovative diagnostic assays. We consider their advantages and limitations, mainly due to stability and storage and their integration into Point-of-Care diagnostics, demonstrating that technologies in some cases are mature enough to meet current clinical needs.

Microarray microRNA profiling of urinary exosomes in a 5XFAD mouse model of Alzheimer's disease

Background

Alzheimer's disease (AD) is an incurable and irreversible neurodegenerative disease, without a clear pathogenesis. Therefore, identification of candidates before amyloid-β plaque (Aβ) deposition proceeds is of major significance for earlier intervention in AD.

Methods

To explore the potential noninvasive earlier biomarkers of AD in a 5XFAD mouse model, microRNAs (miRNAs) from urinary exosomes in 1-month-old pre-Aβ accumulation 5XFAD mice models and their littermate controls were profiled by microarray analysis. The differentially expressed miRNAs were further analyzed via droplet digital PCR (ddPCR).

Results

Microarray analysis demonstrated that 48 differentially expressed miRNAs (18 upregulated and 30 downregulated), of which six miRNAs - miR-196b-5p, miR-339-3p, miR-34a-5p, miR-376b-3p, miR-677-5p, and miR-721 - were predicted to display gene targets and important signaling pathways closely associated with AD pathogenesis and verified by ddPCR.

Conclusions

Urinary exosomal miRNAs showing differences in expression prior to Aβ-plaque deposition were identified. These exosomal miRNAs represent potential noninvasive biomarkers that may be used to prevent AD in clinical applications.

Urine miR-93-5p is a promising biomarker for early detection of HBV-related hepatocellular carcinoma

INTRODUCTION

The mortality rate of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC)continues to increase because sensitive, early and readily available diagnostic tools are lacking. To address this problem, we aimed to identify diagnosticbio markers to be used for early detection of HCC.

MATERIALS AND METHODS

miR-93-5p was selected as a candidate biomarker based on the analyses of relevant Gene Expression Omnibus (GEO) datasets; it was validated using qPCR to quantify its expression levels in tissue, plasma and saliva sample sets.

RESULTS

miR-93-5p was significantly upregulated in HBV-related HCC tissue. Notably, miR-93-5p in plasma and urine was also significantly increased in patients with early HBV-related HCC. The expression of miR-93-5p was significantly and positively correlated in pairwise comparisons of samples (tissue vs. plasma, tissue vs. urine, plasma vs. urine). Moreover, after curative hepatectomy,miR-93-5p in plasma and urine decreased significantly over one month after the curative hepatectomy and returned to normal levels. Furthermore, receiver operating characteristic (ROC) analysis indicated that both plasma and urine miR-39-5p could detect be used to early, advanced and overall HBV-related HCC cases with more than 85% sensitivities and 93% of specificities. Finally, urine miR-93-5p could be used to predict progress-free survival for early HCC patients who received curative hepatectomy and overall survival for advanced HCC patients without curative treatments.

CONCLUSIONS

Plasma and urine miR-93-5p show great promise as potential novel biomarkers for early detection of HBV-related HCC. Moreover, urine miR-93-5p could be used to predict the prognosis of patients with HBV-related HCC.

Urine as a Source of Liquid Biopsy for Cancer

Simple Summary

Tissue biopsy is essential for diagnosis and characterization of a tumor. Recently circulating tumor cells and other tumor-derived nucleic acid can be detected from blood, which is called liquid biopsy. Now this concept has been expanded to many other body fluids including urine. Urine is the least invasive method to obtain a liquid biopsy and can be done anywhere, which allows longitudinal repeated sampling. Here, we review the latest update on urine liquid biopsy in urological and non-urological cancers.

Abstract

Tissue biopsy is the gold standard for diagnosis and morphological and immunohistochemical analyses to characterize cancer. However, tissue biopsy usually requires an invasive procedure, and it can be challenging depending on the condition of the patient and the location of the tumor. Even liquid biopsy analysis of body fluids such as blood, saliva, gastric juice, sweat, tears and cerebrospinal fluid may require invasive procedures to obtain samples. Liquid biopsy can be applied to circulating tumor cells (CTCs) or nucleic acids (NAs) in blood. Recently, urine has gained popularity due to its less invasive sampling, ability to easily repeat samples, and ability to follow tumor evolution in real-time, making it a powerful tool for diagnosis and treatment monitoring in cancer patients. With the development and advancements in extraction methods of urinary substances, urinary NAs have been found to be closely related to carcinogenesis, metastasis, and therapeutic response, not only in urological cancers but also in non-urological cancers. This review mainly highlights the components of urine liquid biopsy and their utility and limitations in oncology, especially in non-urological cancers.

Circulating miRNAs Act as Diagnostic Biomarkers for Bladder Cancer in Urine

MicroRNAs (miRNAs) can be secreted into body fluids and have thus been reported as a new type of cancer biomarker. This study aimed to determine whether urinary miRNAs act as noninvasive biomarkers for diagnosing bladder cancer. Small RNA profiles from urine were generated for 10 patients with bladder cancer and 10 healthy controls by using next-generation sequencing. We identified 50 urinary miRNAs that were differentially expressed in bladder cancer compared with controls, comprising 44 upregulated and six downregulated miRNAs. Pathway enrichment analysis revealed that the biological role of these differentially expressed miRNAs might be involved in cancer-associated signaling pathways. Further analysis of the public database revealed that let-7b-5p, miR-149-5p, miR-146a-5p, miR-193a-5p, and miR-423-5p were significantly increased in bladder cancer compared with corresponding adjacent normal tissues. Furthermore, high miR-149-5p and miR-193a-5p expression was significantly correlated with poor overall survival in patients with bladder cancer. The qRT-PCR approach revealed that the expression levels of let-7b-5p, miR-149-5p, miR-146a-5p and miR-423-5p were significantly increased in the urine of patients with bladder cancer compared with those of controls. Although our results indicated that urinary miRNAs are promising biomarkers for diagnosing bladder cancer, this must be validated in larger cohorts in the future.

miR-21-5p promotes lung adenocarcinoma cell proliferation, migration and invasion via targeting WWC2

OBJECTIVE

Studies have suggested that miR-21-5p and WWC2 are key players in most cancer types, yet the underlying mechanisms in lung adenocarcinoma (LUAD) remain elusive. This study made in-depth research on the two factors-dependent mechanisms underlying LUAD occurrence and development.

METHODS

Bioinformatics methods were employed to identify the miRNA and its target gene of interest. In all, 20 pairs of LUAD tumor tissue samples and matched adjacent normal samples along with 5 LUAD cell lines were collected for evaluating the aberrant expression of miR-21-5p and WWC2. Dual-luciferase reporter assay was performed to validate the targeted relationship between miR-21-5p and WWC2. A series of in vitro experiments including colony formation assay, EdU, wound healing assay and Transwell were conducted for assessment of the LUAD cell biological behaviors. In addition, Western blot was carried out to determine the protein expression of epithelial-mesenchymal transition (EMT)-related proteins.

RESULTS

miR-21-5p was found to be considerably increased in LUAD tissue and cells relative to that in the adjacent tissue and the human bronchial epithelial cells, whereas WWC2 was significantly decreased. Dual-luciferase reporter assay revealed that miR-21-5p targeted WWC2 and down-regulated its expression. Besides, silencing miR-21-5p or overexpressing WWC2 played an inhibitory role in PC-9 cancer cell proliferation, migration and invasion, but such effect was suppressed when miR-21-5p was overexpressed. Furthermore, Western blot uncovered that WWC2 overexpression impeded the EMT process in LUAD cells.

CONCLUSION

miR-21-5p facilitates LUAD cell proliferation, migration and invasion through targeting WWC2, which provides a novel therapeutic target for LUAD treatment.

The usefulness of microRNA in urine and saliva as a biomarker of gastroenterological cancer

MicroRNA (miR) is a type of short non-coding RNA comprising 21-25 nucleotides. While it has been researched widely, its relationship with cancer was clarified recently and it was found to play a significant role in the development and progression of cancer. Furthermore, miR can remain stable for relatively long periods in the blood by being present in exosomes (extracellular microvesicles) or by forming a complex with the Ago2 protein, which gives rise to cancer-specific miR. It is known that miR can indicate the presence and extent of cancer progression. Several reports have proved that miR in urine and saliva is detected in urinary and oral cancer, respectively, and recent studies have also shown it to be present in cases of gastroenterological cancer, showing evidence of it being a biomarker for cancer. To gather further knowledge on this topic, this review aims to summarize the usefulness of urinary and salivary miR as a biomarker for gastroenterological cancer and discuss its existence, stability mechanism, and direction of future research. The findings will be relevant for physicians and oncologists who routinely treat patients with gastric cancers.

Urinary microRNA and mRNA in Tumors

Liquid biopsy is gaining importance in the context of analysis of circulating subcellular components, such as exosomes and nucleic acids, and the investigation of biological fluids is increasing because they express features common to the tissue of origin. Particularly, urine has become one of the most attractive biofluids in clinical practice due to its easy collection approach, its availability of large quantities, and its noninvasiveness. Furthermore, a peculiarity is that, compared to serum or plasma, urine is characterized by a simpler composition that improves isolation and identification of biomarkers. Recent studies have been associated with the investigation of mRNAs and microRNAs as potential noninvasive cancer biomarkers in urine, and to date, several approaches for isolating and measuring urinary nucleic acids have been established, despite still developing. This chapter aims at giving some main published evidences on urinary microRNAs and mRNAs, with the intent to consider their potential translational use in clinical practice.

Cell-free microRNA-1246 in different body fluids as a diagnostic biomarker for esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma is a malignant tumor with unfavorable prognosis. In this study, we investigated the usefulness of microRNA (miR)-1246 detection in various body fluids as a biomarker for this disease. A total of 72 patients with esophageal squamous cell carcinoma were enrolled, and their blood, urine, and saliva samples were collected prior to treatment. Reverse transcription-polymerase chain reaction of miR-1246 was performed, and pre- and postoperative and intraday fluctuations in its expression were examined. The expression of miR-1246 in the blood and urine was significantly higher in the patients with esophageal squamous cell carcinoma than in 50 healthy control subjects. Receiver operating characteristic curves showed that the area under the curve values were 0.91 (sensitivity 91.7%, specificity 76.0%), 0.82 (sensitivity 90.3%, specificity 62.0%), and 0.80 (sensitivity 83.3%, specificity 66.0%) in the serum, urine, and saliva, respectively. A relatively high diagnostic performance of miR-1246 was observed in all samples, which was better than that of the existing biomarkers squamous cell carcinoma antigen, carcinoembryonic antigen, and cytokeratin 19 fragment. No clear correlation was observed in the levels of miR-1246 expression among the three body fluids. Postoperatively, serum samples displayed significantly decreased miR-1246 levels. Although not significant, changes in the miR-1246 levels were observed at all collection times, with large fluctuations in the saliva. Meanwhile, serum miR-1246 expression was found to be associated with the disease prognosis. The results indicate that the levels of miR-1246 in the urine, saliva, and serum are a useful biomarker for esophageal squamous cell carcinoma and support the use of urine samples instead of blood samples for noninvasive diagnosis.

Circulating microRNAs: Biomarkers of disease

MicroRNAs are a class of endogenous noncoding single-stranded RNA molecules with approximately 20-24 nucleotides and are associated with a broad range of biological processes. Researchers found that microRNAs are abundant in tissues, and more importantly, there are also trace circulating microRNAs that exist in biological fluids. In recent years, circulating microRNAs had emerged as promising diagnostic and prognostic biomarkers for the noninvasive detection of diseases with high specificity and sensitivity. More importantly, specific microRNA expression signatures reflect not only the existence of early-stage diseases but also the dynamic development of advanced-stage diseases, disease prognosis prediction, and drug resistance. To date, an increasing number of potential miRNA biomarkers have been reported, but their practical application prospects are still unclear. Therefore, microRNAs, as potential diagnostic and prognostic biomarkers in a variety of diseases, need to be updated, as they are of great importance in the diagnosis, prognosis and prediction of therapeutic responses. In this review, we summary our current understanding of microRNAs as potential biomarkers in the major diseases (e.g., cancers and cardio-cerebrovascular diseases), which provide the basis for the design of diagnosis and treatment plan and the improvement of the cure rate.

Cell lineage-specific methylome and genome alterations in gout

In this study, we examined data from 69 gout patients and 1,455 non-gout controls using a MethylationEPIC BeadChip assay and Illumina HiSeq platform to identify lineage-specific epigenetic alterations and associated genetic factors that contributed to gouty inflammation. Cell lineage-specific differentially methylated sites were identified using CellDMC after adjusting for sex, age, alcohol drinking, smoking status, and smoking history (total pack-years). Different cell lineages displayed distinct differential methylation. Ingenuity Pathway Analysis and NetworkAnalyst indicated that many differential methylated sites were associated with interleukin-1β expression in monocytes. On the UCSC Genome Browser and WashU Epigenome Browser, metabolic trait, cis-methylation quantitative trait loci, genetic, and functional annotation analyses identified nine methylation loci located in interleukin-1β-regulating genes (PRKCZ, CIDEC, VDAC1, CPT1A, BIRC2, BRCA1, STK11, and NLRP12) that were associated specifically with gouty inflammation. All nine sites mapped to active regulatory elements in monocytes. MoLoTool and ReMap analyses indicated that the nine methylation loci overlapped with binding sites of several transcription factors that regulated interleukin-1β production and gouty inflammation. Decreases in PRKCZ and STK11 methylation were also associated with higher numbers of first-degree relatives who also had gout. The gouty-inflammation specific methylome and genome alterations could potentially aid in the identification of novel therapeutic targets.

Identification and Validation a Necroptosis‑related Prognostic Signature and Associated Regulatory Axis in Stomach Adenocarcinoma

BACKGROUND

Gastric cancer (GC) ranks fifth in global cancer incidence and third in cancer-related mortality. The prognosis of GC patients was poor. Necroptosis is a type of regulated cell death mediated by RIP1, RIP3, and MLKL. Necroptosis was found to be involved in antitumor immunity in the cancer immunotherapy.

METHODS

LASSO Cox regression analysis was performed to construct a prognostic signature. Bioinformatics analysis was performed to construct a lncRNA-miRNA-mRNA regulatory axis. qRT-PCR was performed to verify the expression and prognosis of hub gene in STAD.

RESULTS

Most of necroptosis regulators were upregulated, while the mRNA level of TLR3, ALDH2, and NDRG2 was downregulated in STAD versus gastric tissues. The genetic mutation and copy number variation of necroptosis regulator in STAD were also summarized. GO and KEGG pathways analysis revealed that these necroptosis regulators were mainly involved in programmed necrotic cell death and TNF signaling pathway. A necroptosis‑related prognostic signature based on four genes (EZH2, PGAM5, TLR4, and TRAF2) had a good performance in predicting the prognosis of STAD patients. We also identified lncRNA SNHG1/miR-21-5p/TLR4 regulatory axis in the progression in STAD. Verification study suggested that the hub gene TLR4 upregulated in STAD and correlated with a poor overall survival. Moreover, Cox regression analysis revealed that TLR4 expression and clinical stage were independent factors affecting the prognosis of STAD patients.

CONCLUSION

We performed a comprehensive bioinformatics analysis and identified a necroptosis‑related prognostic signature and a lncRNA SNHG1/miR-21-5p/TLR4 regulatory axis in STAD. Further study should be performed to confirm our result.

Ready-to-use nanopore platform for the detection of any DNA/RNA oligo at attomole range using an Osmium tagged complementary probe

Nanopores can serve as single molecule sensors. We exploited the MinION, a portable nanopore device from Oxford Nanopore Technologies, and repurposed it to detect any DNA/RNA oligo (target) in a complex mixture by conducting voltage-driven ion-channel measurements. The detection and quantitation of the target is enabled by the use of a unique complementary probe. Using a validated labeling technology, probes are tagged with a bulky Osmium tag (Osmium tetroxide 2,2′-bipyridine), in a way that preserves strong hybridization between probe and target. Intact oligos traverse the MinION’s nanopore relatively quickly compared to the device’s acquisition rate, and exhibit count of events comparable to the baseline. Counts are reported by a publicly available software, OsBp_detect. Due to the presence of the bulky Osmium tag, probes traverse more slowly, produce multiple counts over the baseline, and are even detected at single digit attomole (amole) range. In the presence of the target the probe is “silenced”. Silencing is attributed to a 1:1 double stranded (ds) complex that does not fit and cannot traverse this nanopore. This ready-to-use platform can be tailored as a diagnostic test to meet the requirements for point-of-care cell-free tumor DNA (ctDNA) and microRNA (miRNA) detection and quantitation in body fluids.

miR-3940-5p/miR-8069 ratio in urine exosomes is a novel diagnostic biomarker for pancreatic ductal adenocarcinoma

Despite the development of several therapeutic options, the prognosis of pancreatic cancer remains poor. One reason for this is the difficulty of diagnosing the disease at an early stage. For example, carbohydrate antigen (CA) 19-9, which is the most widely used biomarker for pancreatic cancer, cannot be used to detect the disease at early stages. Some studies have attempted to find novel biomarkers for pancreatic cancer. The aim of the present study was to find a novel diagnostic biomarker for pancreatic ductal adenocarcinoma (PDAC) in urine exosomes. Exosomes were isolated from urine and serum samples of patients with PDAC and control subjects, or culture media of cancer cell lines. MicroRNAs (miRNAs) were purified from exosomes. Novel biomarker candidates for PDCA were identisfied from urine exosome miRNA using expression profiling, and validated in a larger number of samples using 3D digital PCR. The results of a preliminary analysis of nine PDAC and seven control subjects revealed that the miR-3940-5p/miR-8069 ratio in urine exosomes was elevated in the patients with PDAC. Experiments using cultured cancer cell lines revealed that the elevation of the miR-3940-5p/miR-8069 ratio was specific for PDAC. Furthermore, the elevation of the miR-3940-5p/miR-8069 ratio in exosomes tended to be higher in the urine than in the serum of patients with PDAC. Validation experiments on 43 PDAC, 12 chronic pancreatitis and 25 control subjects demonstrated that the miR-3940-5p/miR-8069 ratio in urine exosomes was elevated in PDAC at a relatively early stage of the disease. When this ratio was used in combination with CA19-9 for the diagnosis of PDAC, the sensitivity and positive predictive value improved to 93.0 and 78.4%, respectively, when either of them was positive. Additionally, the positive predictive value reached 100% when both were positive. The negative predictive value also improved to 89.7% when both were negative. The miR-3940-5p/miR-8069 ratio in urine exosomes may be useful as a tool for the diagnosis of PDAC, particularly when used in combination with CA19-9.

Update on urine as a biomarker in cancer: a necessary review of an old story

Introduction: Cancer causes thousands of deaths worldwide each year. Therefore, monitoring of health status and the early diagnosis of cancer using noninvasive assays, such as the analysis of molecular biomarkers in urine, is essential. However, effective biomarkers for early diagnosis of cancer have not been established in many types of cancer.Areas covered: In this review, we discuss recent findings with regard to the use of urine composition as a biomarker in eleven types of cancer. We also highlight the use of urine biomarkers for improving early diagnosis.Expert opinion: Urinary biomarkers have been applied for clinical application of early diagnosis. The main limitation is a lack of integrated approaches for identification of new biomarkers in most cancer. The utilization of urinary biomarker detection will be promoted by improved detection methods and new data from different types of cancers. With the development of precision medicine, urinary biomarkers will play an increasingly important clinical role. Future early diagnosis would benefit from changes in the utilization of urinary biomarkers.

Urine as a biological modality for colorectal cancer detection

Introduction: The increasing incidence of colorectal cancer (CRC) in young adults warrants early and preferably noninvasive diagnostic modalities. Although the current stool-based assays have had good performance indicators for CRC detection, the overall poor uptake remains a challenging issue. However, alternative blood and urine markers are emerging.Areas covered: This paper discusses the various urinary biomarkers available for the detection of CRC. The more commonly encountered drawbacks are the small number of studies and the size of the study population. We discuss the role of microRNA and ProstaglandinE2 in CRC detection. The emergence of new, low-cost technologies, specifically in the detection of volatile organic compounds (VOCs), presents a promising future. We postulate possible mechanisms for the origin of these VOCs in urine and their role in carcinogenesis.Expert opinion: Urinary biomarkers provide an alternative option to the stool-based screening tests. MicroRNA and ProstaglandinE2 have shown utility in CRC detection. Evidence so far suggests that VOCs could also be a potential biomarker for the detection of CRC. In addition to its interaction within the colon lumen, this altered 'VOC signature' might also play a role in carcinogenesis. Low-cost technology may enable such diagnostic methods to be utilized at the point of care.

MIR-107, MIR-223-3P and MIR-21-5P Reveals Potential Biomarkers in Penile Cancer

BACKGROUND

Inguinal lymph node involvement is the main prognostic factor in patients with penile cancer. However, there is a lack of marker/s for lymph node metastasis. microRNAs have been investigated as potential markers for prognosis of various types of cancer. Taking this into consideration, our main goal was to determine the association of miR-223-3p, miR-107, and miR-21-5p expression with clinicopathological characteristics, as well as presence of lymph node metastasis in patients with penile cancer.

METHODS

Formalin-fixed paraffin-embedded penile squamous cell carcinoma specimens from 50 patients, at diagnosis and prior to any cancer treatment, were obtained. Tissue samples comprising at least 70% malignant cells and adjacent non-tumor tissues were evaluated by using qRT-PCR for expression level of miR-223-3p, miR-107 and miR-21-5p. Additionally, molecular identification of HPV was performed by PCR, and the expression levels of PTEN were analyzed by immunohistochemistry.

RESULTS

Penile squamous cell carcinoma primary tumors presented higher expression of miR-223-3p, miR-107, and miR-21-5p when compared to non-tumor adjacent tissues. Upregulation of miR-223-3p was associated lymph node metastasis. Higher expression of miR-107 was associated with worsening of prognosis (as observed by histological grade II and III, tumors bigger than 2.0 cm, stage III and IV, and lower disease-free survival). In addition, higher expression of miR-107 and miR-21-5p was correlated to the absence of PTEN protein expression.

CONCLUSIONS

Our data demonstrate that higher expression of miR-223-3p, miR-107, and miR-21-5p is correlated with poor prognosis in penile cancer. The upregulation of these microRNAs potentially affect critical cancer pathways and may be important for the prognosis and response to therapy in penile cancer.

Cancer metabolomic markers in urine: evidence, techniques and recommendations

Urinary tests have been used as noninvasive, cost-effective tools for screening, diagnosis and monitoring of diseases since ancient times. As we progress through the 21st century, modern analytical platforms have enabled effective measurement of metabolites, with promising results for both a deeper understanding of cancer pathophysiology and, ultimately, clinical translation. The first study to measure metabolomic urinary cancer biomarkers using NMR and mass spectrometry (MS) was published in 2006 and, since then, these techniques have been used to detect cancers of the urological system (kidney, prostate and bladder) and nonurological tumours including those of the breast, ovary, lung, liver, gastrointestinal tract, pancreas, bone and blood. This growing field warrants an assessment of the current status of research developments and recommendations to help systematize future research.

Urinary MicroRNAs as Emerging Class of Noninvasive Biomarkers

MicroRNAs (miRNAs) are endogenous noncoding RNAs, which regulate gene expression on the post-transcriptional level. Since miRNAs are involved in the regulation of apoptosis, cellular proliferation, differentiation, and other important cellular processes, their deregulation is important for the development of a wide range of diseases including cancer. Apart from tissue, specific disease-related miRNA signatures can be found in body fluids as well. Especially for urologic diseases or injuries, urine miRNAs represent a promising group of biomarkers. Despite a large number of studies describing the importance of urinary miRNAs, there is a lack of recommendations for urine management and subsequent miRNA analysis. Thus, in this chapter, we aim to describe the origin and functions of urinary miRNAs and discuss the technical aspects of their detection including the pre-analytical phase principles and new directions in quantification, which could forward urine miRNA into clinical practice.

A novel urinary microRNA biomarker panel for detecting gastric cancer

BACKGROUND

Gastric cancer (GC) is one of the most common causes of cancer deaths worldwide; however, reliable and non-invasive screening methods for GC are not established. Therefore, we conducted this study to develop a biomarker for GC detection, consisting of urinary microRNAs (miRNAs).

METHODS

We matched 306 participants by age and sex [153 pairs consisting of patients with GC and healthy controls (HCs)], then randomly divided them across three groups: (1) the discovery cohort (4 pairs); (2) the training cohort (95 pairs); and (3) the validation cohort (54 pairs).

RESULTS

There were 22 urinary miRNAs with significantly aberrant expressions between the two groups in the discovery cohort. Upon multivariate analysis of the training cohort, urinary expression levels of miR-6807-5p and miR-6856-5p were significantly independent biomarkers for diagnosis of GC, in addition to Helicobacter pylori (H. pylori) status. A diagnostic panel that combined these 2 miRNAs and H. pylori status distinguished between HC and GC samples with an area under the curve (AUC) = 0.736. In the validation cohort, urinary miR-6807-5p and miR-6856-5p showed significantly higher expression levels in the GC group, and the combination biomarker panel of miR-6807-5p, miR-6856-5p, and H. pylori status also showed excellent performance (AUC = 0.885). In addition, this biomarker panel could distinguish between HC and stage I GC patients with an AUC = 0.748. Urinary expression levels of miR-6807-5p and miR-6856-5p significantly decreased to undetectable level after curative resection of GC.

CONCLUSIONS

This novel biomarker panel enables early and non-invasive detection of GC.

Expression and significance of urinary microRNA in patients with chronic hepatitis B

The aim of this study was to investigate the alterations of urinary microRNA (miRNA) expression and explore its clinical significance in patients with chronic hepatitis B (CHB).The expression levels of urinary miRNA were detected by miRNA microarray and quantitative reverse transcription polymerase chain reaction (qRT-PCR) from 106 CHB and 40 healthy controls (Ctrl) subjects. The correlation between the levels of miRNA expression and clinical characteristics were analyzed. Receiver-operator characteristic (ROC) curves were generated to determine the specificity and sensitivity of each individual miRNA. MiRNAs expression were further measured by PCR from exosomes, which were isolated from urine samples. LX2 cells were transfected with miRNA inhibitor and accumulation of cytoplasmic lipid droplets was analyzed by Oil Red O staining.miRNA expression profile analysis showed that 22 miRNAs were upregulated and 55 miRNAs were downregulated in CHB patients compared with Ctrl subjects (fold-change>1.5 and P < .05). miR-92b-3p, miR-770-5p, miR-5196-5p, and miR-7855-5p were significantly higher (P < .0001) in CHB subjects than in Ctrl subjects. ROC curve analysis showed that these four miRNAs were sensitive and specific enough to distinguish CHB and Ctrl subjects. The levels of miR-92b-3p expression were negatively correlated with total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and APOA-1. Moreover, in vitro experiments indicated that inhibition of miR-92b-3p increased lipid droplet formation in LX2 cells.Aberrant expression of miRNAs has been observed in urine of CHB patients. Our findings may provide novel insights into the pathogenesis of CHB and may assist in the diagnosis of patients with CHB.

Potential diagnostic and prognostic value of plasma long noncoding RNA LINC00086 and miR-214 expression in gastric cancer

BACKGROUND

Plasma carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9), and cancer antigen 72-4 (CA72-4) are common markers which are useful in the diagnosis and prognosis of GC. However, their sensitivity and specificity in GC remain unsatisfactory. Identification of cancer diagnosed-biomarkers would be of great value.

OBJECTIVE

Evaluate the diagnostic and prognostic value of LINC00086 and miR-214 in GC.

METHODS

In this study, we determined the expression of LINC00086 and miR-214 in GC by qRT-PCR. Additionally, we investigated the relationship between various clinicopathological features of GC patients and LINC00086 or miR-214 expression, and evaluated the diagnostic and prognostic value of LINC00086 and miR-214 in GC.

RESULTS

In this study, we found that plasma LINC00086 expression was significantly lower, whereas plasma miR-214 expression was significantly higher in GC patients than in normal individuals. LINC00086 and miR-214 exhibited high sensitivity and specificity in diagnosing GC. Additionally, GC patients with low LINC00086 or high miR-214 expression were likely to have larger tumors, lymphatic metastasis, larger TNM stage, and higher CEA and CA19-9 levels. Moreover, GC patients with low LINC00086 or high miR-214 expression showed lower survival rates. Lymphatic metastasis, LINC00086, and miR-214 are independent factors affecting patient diagnosis.

CONCLUSIONS

LINC00086 and miR-214 are potentially diagnostic and prognostic markers for GC.

Non-coding RNAs in regulating gastric cancer metastasis

Gastric cancer is one of the leading causes of cancer-related deaths worldwide, and mortality remains high, especially in East Asia. At present, the main method to diagnose gastric cancer is pathological biopsy. At the time of diagnosis, most patients have been diagnosed with advanced cancer and metastasis. The treatment of gastric cancer patients is mainly radical surgical resection and chemoradiotherapy, while patients with metastatic tumor have great challenges to radical surgery and are prone to drug resistance. Metastasis is an important factor affecting tumor development. In addition, evidence accumulated in the literature indicates that non-coding RNA plays a key role in tumor metastasis. This article reviews the role of ncRNAs in gastric cancer metastasis and discusses the regulatory mechanism in the development and treatment of gastric cancer.

miR-21-5p Suppressed the Sensitivity of Hepatocellular Carcinoma Cells to Cisplatin by Targeting FASLG

Accumulating evidence has suggested that microRNAs play important roles in the development of hepatocellular carcinoma (HCC) and are involved in drug resistance. miR-21-5p was overexpressed in a variety of cancers and promoted the tumorigenesis; however, the function of miR-21-5p in HCC still remains unknown. In this study, our results showed that miR-21-5p was highly expressed in HCC tissues and cell lines. Notably, the level of miR-21-5p was relatively higher in cisplatin (DDP)-resistant HCC patients. Overexpression of miR-21-5p attenuated the inhibitory effect of DDP on the proliferation and apoptosis of HCC cells. Mechanistically, the luciferase report assay-identified FAS ligand (FASLG) was a direct target of miR-21-5p. Overexpression of miR-21-5p decreased both the mRNA and protein levels of FASLG in HCC cells. FASLG was downregulated in HCC tissues and was significantly negatively correlated with the expression of miR-21-5p. Restoring the expression of FASLG upregulated the chemosensitivity of HCC cells expressing miR-21-5p. In conclusion, our results demonstrated that miR-21-5p targeted FASLG and suppressed the sensitivity of HCC cells to DDP treatment.

Genome-wide microRNA screening reveals miR-582-5p as a mesenchymal stem cell-specific microRNA in subchondral bone of the human knee joint

Emerging evidence suggests that microRNAs (miRNAs) may be pathologically involved in osteoarthritis (OA). Subchondral bone (SCB) sclerosis is accounted for the knee osteoarthritis (KOA) development and progression. In this study, we aimed to screen the miRNA biomarkers of KOA and investigated whether these miRNAs regulate the differentiation potential of mesenchymal stem cells (MSCs) and thus contributing to SCB. We identified 48 miRNAs in the blood samples in KOA patients (n = 5) through microarray expression profiling detection. After validation with larger sample number, we confirmed hsa-miR-582-5p and hsa-miR-424-5p were associated with the pathology of SCB sclerosis. Target genes prediction and pathway analysis were implemented with online databases, indicating these two candidate miRNAs were closely related to the pathways of pluripotency of stem cells and pathology of OA. Surprisingly, mmu-miR-582-5p (homology of hsa-miR-582-5p) was downregulated in osteogenic differentiation and upregulated in adipogenic differentiation of mesenchymal progenitor C3H10T1/2 cells, whereas mmu-mir-322-5p (homology of hsa-miR-424-5p) showed no change through the in vitro study. Supplementing mmu-miR-582-5p mimics blocked osteogenic and induced adipogenic differentiation of C3H10T1/2 cells, whereas silencing of the endogenous mmu-miR-582-5p enhanced osteogenic and repressed adipogenic differentiation. Further mechanism studies showed that mmu-miR-582-5p was directly targeted to Runx2. Mutation of putative mmu-miR-582-5p binding sites in Runx2 3' untranslated region (3'UTR) could abolish the response of the 3'UTR-luciferase construct to mmu-miR-582-5p supplementation. Generally speaking, our data suggest that miR-582-5p is an important biomarker of KOA and is able to regulate osteogenic and adipogenic differentiation of MSCs via targeting Runx2. The study also suggests that miR-582-5p may play a crucial role in SCB sclerosis of human KOA.

Comparison of plasma and urinary microRNA-483-5p for the diagnosis of adrenocortical malignancy

INTRODUCTION

Minimally invasive circulating microRNAs might be used for the preoperative differentiation of adrenocortical carcinoma (ACC) and adrenocortical adenoma (ACA). So far, the best blood-borne microRNA biomarker of ACC is circulating hsa-miR-483-5p. The expression of urinary hsa-miR-483-5p as a non-invasive marker of malignancy and its correlation with plasma hsa-miR-483-5p, has not been investigated, yet.

AIM

Our aim was to investigate the expression of urinary hsa-miR-483-5p and its correlation with its plasma counterpart.

METHODS

Plasma and urinary samples from 23 ACC and 23 ACA patients were analysed using real-time RT-qPCR. To evaluate the diagnostic applicability of hsa-miR-483-5p, ROC-analysis was performed.

RESULTS

Significant overexpression of hsa-miR-483-5p was observed in carcinoma patients' plasma samples compared to adenoma patients' (p < 0.0001, sensitivity: 87%, specificity: 78.3%). In urinary samples, however, no significant difference could be detected between ACC and ACA patients.

CONCLUSIONS

Plasma hsa-miR-483-5p has been confirmed as significantly overexpressed in adrenocortical cancer patients and thus might be exploited as a minimally invasive preoperative marker of malignancy. The applicability of urinary hsa-miR-483-5p for the diagnosis of adrenocortical malignancy could not be confirmed.

Droplet digital PCR improves urinary exosomal miRNA detection compared to real-time PCR

OBJECT

Quantification of urinary miRNAs can be challenging especially for low abundance miRNAs. We aimed to optimize the quantification of urinary exosomal miRNAs and compare the performance efficiency between droplet digital PCR (ddPCR) and real-time quantitative PCR (qPCR).

METHODS

We optimized a number of parameters for ddPCR such as annealing temperatures, annealing time and PCR cycle number. We also compared the performance of ddPCR and qPCR.

RESULTS

By comparing the fluorescence amplification separation, the optimal annealing temperature was 59 °C, optimal annealing time was 60s and optimal cycle number was 45 for measuring urinary exosomal miRNAs. ddPCR had much higher technical sensitivity compared to qPCR. The minimal detectable concentration of miR-29a was <50 copies/μL by ddPCR compared to 6473 copies/μL for qPCR. Also, ddPCR generated more consistent results for serially diluted samples compared to qPCR. ddPCR generated smaller within-run variations than qPCR though this did not reach statistical significance. It also resulted in better reproducibility with smaller between-run variations.

CONCLUSIONS

Optimization of urinary exosomal miRNA ddPCR assay is dependent on assessing key variables including experimental annealing temperature and time as well as the number of PCR cycles. ddPCR has a higher sensitivity, reproducibility, and accuracy in comparison to qPCR.

Clinical Significance of Circulatory miRNA-21 as an Efficient Non-Invasive Biomarker for the Screening of Lung Cancer Patients

Dysregulation in the miRNA-21 expression has been previously observed in a number of malignancies and not only in the tumor cell itself but also in the body fluids of the cancer patients. The present study aimed to find out the clinical significance of cell-free circulating miRNA-21 as an efficient non-invasive biomarker for the screening of lung cancer patients. The present case-control study included plasma samples from 80 lung cancer patients and 80 healthy controls. Magnetic bead technology was used for efficient miRNA isolation and advanced TaqMan miRNA assays were used for the quantification of miRNA-21 level in the plasma of the lung cancer patients and healthy individuals.The overall mean relative expression level of plasma miRNA-21 among lung cancer patients (2.32±1.7) was higher when compared to healthy individuals (0.715 ± 0.48) and it showed a significant difference of p<0.0001. The area under ROC curve was 0.8913 [95% confidence interval (CI): 0.8394 to 0.9431, p< 0.0001] and the sensitivity and specificity were both 80.0% when the cut-off value was 1.207. In conclusion, plasma miRNA-21 can be efficiently extracted by the magnetic bead technology and quantified by the advanced TaqMan miRNA assay. Plasma miRNA-21 showed a high ability to distinguish between lung cancer patients and healthy individuals, therefore can be used as an efficient non-invasive biomarker for the screening of Lung cancer patients.

Clinical Significance of Circulatory miRNA-21 as an Efficient Non-Invasive Biomarker for the Screening of Lung Cancer Patients

Dysregulation in the miRNA-21 expression has been previously observed in a number of malignancies and not only in the tumor cell itself but also in the body fluids of the cancer patients. The present study aimed to find out the clinical significance of cell-free circulating miRNA-21 as an efficient non-invasive biomarker for the screening of lung cancer patients. The present case-control study included plasma samples from 80 lung cancer patients and 80 healthy controls. Magnetic bead technology was used for efficient miRNA isolation and advanced TaqMan miRNA assays were used for the quantification of miRNA-21 level in the plasma of the lung cancer patients and healthy individuals.The overall mean relative expression level of plasma miRNA-21 among lung cancer patients (2.32±1.7) was higher when compared to healthy individuals (0.715 ± 0.48) and it showed a significant difference of p<0.0001. The area under ROC curve was 0.8913 [95% confidence interval (CI): 0.8394 to 0.9431, p< 0.0001] and the sensitivity and specificity were both 80.0% when the cut-off value was 1.207. In conclusion, plasma miRNA-21 can be efficiently extracted by the magnetic bead technology and quantified by the advanced TaqMan miRNA assay. Plasma miRNA-21 showed a high ability to distinguish between lung cancer patients and healthy individuals, therefore can be used as an efficient non-invasive biomarker for the screening of Lung cancer patients.

[Urinary long non-coding RNA H19 may serve as a biomarker for early diagnosis of acute intestinal necrosis]

OBJECTIVE

To explore the value of urinary long non-coding RNA(lncRNA) H19 in the differential diagnosis of acute intestinal necrosis against other abdominal emergencies.

METHODS

Surgical specimens of necrotic intestinal tissues, adjacent normal intestinal tissues, and serum and urine samples were collected from 51 patients with acute intestinal necrosis, and analyzed along with the serum and urine samples from 51 healthy controls, patients with 10 different acute abdominal conditions(35 cases for each condition), and patients with breast cancer, gastric cancer, bladder cancer, acute myeloid leukemia, and lung cancer(10 cases for each malignancy). The expression levels of H19 were measured with quantitative PCR in the collected samples. Receiver-operating characteristic(ROC)curves were used to determine the diagnostic value of serum and urine H19 levels for acute intestinal necrosis.

RESULTS

The 51 patients with acute intestinal necrosis included 35 women and 26 men(mean age of 74.4 years) with arterial thrombosis as the dominant etiology(26 cases). Compared with that in normal intestinal tissues, H19 was significantly overexpressed by 11.2 times in necrotic intestinal tissues(P < 0.001). Serum and urine H19 expression levels did not differ significantly among the healthy controls, patients with other acute abdominal conditions and malignancies(P > 0.05). Serum and urine H19 levels were significantly up-regulated in patients with acute intestinal necrosis as compared with those in the other subjects included in the analysis(P < 0.001). In patients with acute intestinal necrosis, H19 levels in the necrotic intestinal tissue, serum and urine samples were significantly correlated with correlation coefficients of 0.974(tissue vs serum), 0.967(serum vs urine), and 0.917(tissue vs urine). In ROC curve analysis, the areas under curves(AUCs)of serum and urine H19 for diagnosis of acute intestinal necrosis were 0.951 and 0.915, respectively; their diagnostic sensitivities were 94% and 79.6%, respectively, and they both had a diagnostic specificity of 100%.

CONCLUSIONS

In patients with acute intestinal necrosis, H19 is overexpressed in necrotic intestinal tissues, from which it is released into the blood circulation and urine. Urinary H19 may serve as a novel and non-invasive biomarker that assists in early diagnosis of acute intestinal necrosis.

Vasodilator-stimulated phosphoprotein (VASP), a novel target of miR-4455, promotes gastric cancer cell proliferation, migration, and invasion, through activating the PI3K/AKT signaling pathway

Background

MicroRNAs (miRNAs) are small non-coding RNAs which play important roles in the carcinogenesis of gastric cancer (GC). Expression profiling of miRNAs in paired gastric cancer and adjacent normal gastric tissues has demonstrated that miR-4455 is down-regulated in gastric cancer tissues, but its functional role in the carcinogenesis of GC had not previously been investigated.

Aims

The purpose of this study was to investigate the functional and biological mechanisms of miR-4455 in the progression of GC, in vitro.

Methods

Expression of miR-4455 was compared in human GC tissue samples and paired adjacent normal tissue samples. The in vitro effects of miR-4455 expression in MGC-803 cells on their proliferation, invasion, and migration were assessed by MTT assays and 5-bromo-2′-deoxyuridine staining, matrigel-invasion analysis and wound healing assays. Bioinformatics analysis (using PicTar, target scan and miRBase target) was used to identify potential targets for miR-4455, and the luciferase reporter assay, qRT-PCR and Western-blotting analyses were used to confirm VASP as the target of miR-4455. In addition, the effects of downregulation of VASP on the activation of PI3K/AKT signaling pathway were measured using Western-blot analysis.

Results

The expression of miR-4455 was markedly down-regulated in gastric cancer tissues vs. adjacent normal tissues, and miR-4455 expression inhibited the proliferation, invasion and migration of MGC-803 GC cells in vitro. Luciferase reporter assays revealed that miR-4455 inhibited VASP expression by targeting the 3′-UTR sequence of VASP. Furthermore, silencing of VASP markedly inhibited the activation of the PI3K/AKT signaling pathway.

Conclusion

Our results suggest that miR-4455 functions as a tumor suppressor in gastric cancer, by targeting VASP leading to activation of the PI3K/AKT signaling pathway and the inhibition of VASP mediated proliferation, migration and invasion of gastric cancer cells.

Electronic supplementary material

The online version of this article (10.1186/s12935-018-0573-4) contains supplementary material, which is available to authorized users.

MicroRNAs as potential biomarkers for diagnosis, therapy and prognosis of gastric cancer

Despite the widespread use of endoscopy and conventional tumor biomarkers, gastric cancer (GC) remains one of the most frequent causes of cancer-related deaths worldwide due to its late diagnosis and poor response to treatment. Valuable and practical biomarkers are urgently needed to screen patients with a high risk of GC that can complement endoscopic diagnosis. Such biomarkers will enable the efficient prediction of therapeutic response and prognosis of GC patients and favor the establishment of an effective treatment strategy for each and every patient. MicroRNAs (miRNAs) are a class of small non-coding RNA sequences that play important roles in modulating key biological processes by regulating the expression of target genes. Expectedly, miRNAs are abnormally expressed within the tumor tissue and in associated biological fluids of GC patients including their blood, gastric juice, and urine. Accumulating evidence indicates that miRNAs are potential biomarkers with multiple diagnostic functions for GC. Here, we review recent advances and challenges in using miRNAs, particularly biofluid miRNAs, as GC biomarkers with potential clinical applications including diagnosing, clinically staging, and predicting malignant behaviors, therapy response, recurrence after surgery and survival time.

Inhibition of miR-21-5p suppresses high glucose-induced proliferation and angiogenesis of human retinal microvascular endothelial cells by the regulation of AKT and ERK pathways via maspin

The aim of the present study is to investigate the role of miR-21-5p in angiogenesis of human retinal microvascular endothelial cells (HRMECs). HRMECs were incubated with 5 mM glucose, 30 mM glucose or 30 mM mannitol for 24 h, 48 h or 72 h. Then, HRMECs exposed to 30 mM glucose were transfected with miR-21-5p inhibitor. We found that high glucose increased the expression of miR-21-5p, VEGF, VEGFR2 and cell proliferation activity. Inhibition of miR-21-5p reduced high glucose-induced proliferation, migration, tube formation of HRMECs, and reversed the decreased expression of maspin as well as the abnormal activation of PI3K/AKT and ERK pathways. Down-regulation of maspin by siRNA significantly increased the activities of PI3K/AKT and ERK pathways. In conclusion, inhibition of miR-21-5p could suppress high glucose-induced proliferation and angiogenesis of HRMECs, and these effects may partly dependent on the regulation of PI3K/AKT and ERK pathways via its target protein maspin.