Six Serum-Based miRNAs as Potential Diagnostic Biomarkers for Gastric Cancer

Ultrasensitive fluorescence microRNA biosensor by coupling hybridization-initiated exonuclease I protection and tyramine signal amplification

Tyramine signal amplification (TSA) has made its mark in immunoassay due to its excellent signal amplification ability and short reaction time, but its application in nucleic acid detection is still very limited. Herein, an ultrasensitive microRNA (miRNA) biosensor by coupling hybridization-initiated exonuclease I (Exo I) protection and TSA strategy was established. Target miRNA is complementarily hybridized to the biotin-modified DNA probe to form a double strand, which protects the DNA probe from Exo I hydrolysis. Subsequently, horseradish peroxidase (HRP) is attached to the duplex via the biotin-streptavidin reaction and catalyzes the deposition of large amounts of biotin-tyramine in the presence of hydrogen peroxide (H2O2), followed by the conjugation of signal molecule streptavidin-phycoerythrin (SA-PE), which generates an intense fluorescence signal upon laser excitation. This method gave broad linearity in the range of 0.1 fM - 10 pM, yielding a detection limit as low as 74 aM. An increase in sensitivity of 4 orders of magnitude was observed compared to the miRNA detection without TSA amplification. This biosensor was successfully applied to the determination of miR-21 in breast cancer cells and human serum. By further design of specific DNA probes and coupling with the Luminex xMAP technology, it could be easily extended to multiplex miRNA assay, which possesses great application potential in clinical diagnosis.

Non-Coding RNA as Biomarkers and Their Role in the Pathogenesis of Gastric Cancer-A Narrative Review

Non-coding RNAs (ncRNAs) represent a broad family of molecules that regulate gene expression, including microRNAs, long non-coding RNAs and circular RNAs, amongst others. Dysregulated expression of ncRNAs alters gene expression, which is implicated in the pathogenesis of several malignancies and inflammatory diseases. Gastric cancer is the fifth most frequently diagnosed cancer and the fourth most common cause of cancer-related death. Studies have found that altered expression of ncRNAs may contribute to tumourigenesis through regulating proliferation, apoptosis, drug resistance and metastasis. This review describes the potential use of ncRNAs as diagnostic and prognostic biomarkers. Moreover, we discuss the involvement of ncRNAs in the pathogenesis of gastric cancer, including their interactions with the members of major signalling pathways.

Roles and application of exosomes in the development, diagnosis and treatment of gastric cancer

As important messengers of intercellular communication, exosomes can regulate local and distant cellular communication by transporting specific exosomal contents and can also promote or suppress the development and progression of gastric cancer (GC) by regulating the growth and proliferation of tumor cells, the tumor-related immune response and tumor angiogenesis. Exosomes transport bioactive molecules including DNA, proteins, and RNA (coding and noncoding) from donor cells to recipient cells, causing reprogramming of the target cells. In this review, we will describe how exosomes regulate the cellular immune response, tumor angiogenesis, proliferation and metastasis of GC cells, and the role and mechanism of exosome-based therapy in human cancer. We will also discuss the potential application value of exosomes as biomarkers in the diagnosis and treatment of GC and their relationship with drug resistance.

Identification and validation of molecular subtypes and prognostic signature for stage I and stage II gastric cancer based on neutrophil extracellular traps

Purpose

This study identified subtypes and prognostic signature of stage I and stage II gastric cancer based on neutrophil extracellular trap (NET)-related genes.

Methods

The gene expression data associated with stage I and stage II gastric cancer were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. NET-related genes were obtained from previous reference. Differentially expressed NET-related genes were selected by consensus cluster analysis. The differences in immune infiltration between two subtypes were analyzed. Prognosis-related genes were further screened by univariate Cox regression analysis. Gene Set Enrichment Analysis (GSEA) of prognostic signatures was conducted with clusterprofiler. Finally, a miRNA-mRNA-transcription factor (TF) network was constructed.

Results

Total 43 differential NET-related genes were obtained and two subtypes were obtained based on these genes. Patients of cluster 2 had a better prognosis compared to cluster 1. Eight types of immune cells were differential in infiltration level between two subtypes. Following univariate Cox regression analysis, two genes of CXC chemokine receptor 4 (CXCR4) and nuclear factor, erythroid 2-like 2 (NFE2L2) significantly related to patient survival were selected. GSEA of single gene revealed that CXCR4 was associated with allograft rejection and NFE2L2 was associated with drug metabolism-cytochrome P450. A network with 421 miRNA-mRNA-TF regulatory pairs was constructed.

Conclusion

The present study identified two subtypes and a prognostic signature for stage I and stage II gastric cancer based on NET-related genes.

Aptamer-Based Functionalized SERS Biosensor for Rapid and Ultrasensitive Detection of Gastric Cancer-Related Biomarkers

Background

Gastric cancer (GC) as is the second deadliest malignancy still lacks rapid, simple and economical detection and early clinical screening techniques. Surface-enhanced Raman spectroscopy (SERS) is a spectroscopic technique based on the surface plasmon resonance of precious metal nanoparticles, which can effectively detect low-abundance tumor markers. Combining SERS technology with sensors has high potential in the diagnosis and screening of GC.

Methods

A novel Au/Si nano-umbrella array (Au/SiNUA) was prepared as a SERS substrate and the substrate was functionalized using the corresponding tumor marker aptamers for the detection of clinical biological samples using a one-step recognition release mechanism. Optimization of aptamer and complementary chain concentrations and detection time for optimal sensor preparation.

Results

Au/SiNUA were tested to have good SERS enhancement activity. The proposed aptamer biosensor has good specificity and stability, with a low detection time of 18 min and a limit of detection (LOD) at the fM level, which is superior to most of the methods reported so far; and the accuracy of the clinical assay is comparable to that of the ELISA method. The expression levels of PDGF-B and thrombin in the serum of GC patients and healthy individuals can be effectively detected and differentiated.

Conclusion

The ultrasensitive and specific aptamer biosensor is highly feasible for the diagnosis and screening of GC and has good application prospects.

Circulating microRNA Panels for Detection of Liver Cancers and Liver-Metastasizing Primary Cancers

Malignant liver tumors, including primary malignant liver tumors and liver metastases, are among the most frequent malignancies worldwide. The disease carries a poor prognosis and poor overall survival, particularly in cases involving liver metastases. Consequently, the early detection and precise differentiation of malignant liver tumors are of paramount importance for making informed decisions regarding patient treatment. Significant research efforts are currently directed towards the development of diagnostic tools for different types of cancer using minimally invasive techniques. A prominent area of focus within this research is the evaluation of circulating microRNA, for which dysregulated expression is well documented in different cancers. Combining microRNAs in panels using serum or plasma samples derived from blood holds great promise for better sensitivity and specificity for detection of certain types of cancer.

Circ-SHPRH in human cancers: a systematic review and meta-analysis

Circular RNA (circRNA) molecules are noncoding RNAs with ring-like structures formed by covalent bonds and are characterized by no 5'caps or 3'polyadenylated tails. Increasing evidence shows that circRNAs may play an important role in tumorigenesis and cancer metastasis. Circ-SHPRH originates from exons 26-29 of the SHPRH gene, and it is closely associated with human cancers. We searched PubMed, Web of Science, and Embase databases for relevant literatures until 24 December 2022. Eighteen research papers were included in this review, and 11 papers were selected for meta-analysis after screening. Three eligible published studies about circ-SHPRH were enrolled based on their tumor diagnosis aspect, 7 eligible published studies were related to overall survival (OS), and 3 eligible published studies were related to tumor grade. Many studies have shown that circ-SHPRH acts as a miRNA sponge or encodes a protein to regulate downstream genes or signal pathways, and exerts specific biological functions that affect the proliferation, invasion, and apoptosis of cancer cells. Meta-analysis showed that patients with high expression of circ-SHPRH had better OS (HR = 0.53, 95% CI 0.38-0.74, p-value <0.05) and lower TNM stage (HR = 0.33, 95% CI 0.18-0.62, p-value = 0.001). In addition, circ-SHPRH has potential diagnostic value (AUC = 0.8357). This review will help enrich our understanding of the role and mechanism of circ-SHPRH in human cancers. Circ-SHPRH has the potential to be a novel diagnostic and prognostic biomarker for various solid cancers.

NGS Data Repurposing Allows Detection of tRNA Fragments as Gastric Cancer Biomarkers in Patient-Derived Extracellular Vesicles

Transfer RNA fragments (tRFs) have gene silencing effects similarly to miRNAs, can be sorted into extracellular vesicles (EVs) and are emerging as potential circulating biomarkers for cancer diagnoses. We aimed at analyzing the expression of tRFs in gastric cancer (GC) and understanding their potential as biomarkers. We explored miRNA datasets from gastric tumors and normal adjacent tissues (NATs) from TCGA repository, as well as proprietary 3D-cultured GC cell lines and corresponding EVs, in order to identify differentially represented tRFs using MINTmap and R/Bioconductor packages. Selected tRFs were validated in patient-derived EVs. We found 613 Differentially Expressed (DE)-tRFs in the TCGA dataset, of which 19 were concomitantly upregulated in TCGA gastric tumors and present in 3D cells and EVs, but barely expressed in NATs. Moreover, 20 tRFs were expressed in 3D cells and EVs and downregulated in TCGA gastric tumors. Of these 39 DE-tRFs, 9 tRFs were also detected in patient-derived EVs. Interestingly, the targets of these 9 tRFs affect neutrophil activation and degranulation, cadherin binding, focal adhesion and the cell-substrate junction, highlighting these pathways as major targets of EV-mediated crosstalk with the tumor microenvironment. Furthermore, as they are present in four distinct GC datasets and can be detected even in low quality patient-derived EV samples, they hold promise as GC biomarkers. By repurposing already available NGS data, we could identify and cross-validate a set of tRFs holding potential as GC diagnosis biomarkers.

Crosstalk between miRNAs and DNA Methylation in Cancer

miRNAs are some of the most well-characterized regulators of gene expression. Integral to several physiological processes, their aberrant expression often drives the pathogenesis of both benign and malignant diseases. Similarly, DNA methylation represents an epigenetic modification influencing transcription and playing a critical role in silencing numerous genes. The silencing of tumor suppressor genes through DNA methylation has been reported in many types of cancer and is associated with tumor development and progression. A growing body of literature has described the crosstalk between DNA methylation and miRNAs as an additional layer in the regulation of gene expression. Methylation in miRNA promoter regions inhibits its transcription, while miRNAs can target transcripts and subsequently regulate the proteins responsible for DNA methylation. Such relationships between miRNA and DNA methylation serve an important regulatory role in several tumor types and highlight a novel avenue for potential therapeutic targets. In this review, we discuss the crosstalk between DNA methylation and miRNA expression in the pathogenesis of cancer and describe how miRNAs influence DNA methylation and, conversely, how methylation impacts the expression of miRNAs. Finally, we address how these epigenetic modifications may be leveraged as biomarkers in cancer.

NF1-Related MicroRNA Gene Polymorphisms and the Susceptibility to Soft Tissue Sarcomas: A Case-Control Study

Soft tissue sarcomas (STS) are rare malignant tumors of mesenchymal origin, which are easy to metastasize and relapse and are a great threat to human health. In our previous study, the abnormal expression of neurofibromin 1 (NF1) is observed in tumor tissue of STS, and the NF1 gene is regulated by miRNAs. The study aimed to assess the association between NF1-related miRNA gene polymorphisms and the risk of STS. In this case-control study, the information and peripheral blood were collected from 169 patients with STS and 170 healthy controls. Six single-nucleotide polymorphisms of the NF1-related miRNAs were investigated and genotyped using a Sequenom MassARRAY® matrix-assisted laser desorption/ionization time-of-flight mass spectrometry platform. The association between the polymorphisms and the risk of STS was estimated using unconditional logistic regression analysis. There was a significant statistical difference on genotype distribution of miR-199a2 rs12139213 between the case group and the control group (p = 0.026). Comparing with individuals with wild-type AA, individuals with the AT/TT genotype had a 1.753-fold (odds ratio [OR] = 1.753, 95% confidence interval [CI] = 1.090-2.819, p = 0.021) increased risk of STS and 1.907-fold (OR = 1.907, 95% CI = 1.173-3.102, p = 0.009) increased risk of STS adjusted for age and smoking status. Individuals with the AG/GG genotype for miR24-3p rs4743988 displayed a significantly reduced risk of STS compared with individuals with homozygous mutations AA (OR = 0.605, 95% CI = 0.376-0.973, p = 0.038). Individuals carrying the AT/TT genotype for miR-199a2 rs12139213 or the AA genotype for miR24-3p rs4743988 may be susceptible to STS, which could be potential biomarkers for the diagnosis of STS.

Diagnostic and Prognostic Value of Serum miR-296-5p and miR-28-3p in Human Gastric Cancer

Background: Previous studies reported the use of microRNAs (miRNAs) as diagnostic and/or prognostic biomarkers for various cancers, including gastric cancer (GC). This study evaluated the diagnostic and prognostic significance of serum miR-296-5p and miR-28-3p in GC. Materials and Methods: Serum samples of 90 patients with GC and 90 healthy individuals, and 20 pairs of tissue specimens from patients with GC were collected. The expression of miR-296-5p and miR-28-3p in both the serum and tissue samples were detected using quantitative real-time polymerase chain reaction analysis. The diagnostic and prognostic values of miR-296-5p and miR-28-3p were evaluated by using receiver operating characteristic curve and Kaplan-Meier analyses, respectively. Results: Compared with the healthy controls, the expression of miR-296-5p in the serum and tissues of patients with GC was significantly upregulated, whereas that of miR-28-3p was significantly downregulated. High miR-296-5p and low miR-28-3p levels in the serum significantly correlated with larger tumor size (>5 cm), lymph node metastasis, and TNM stage III+IV. The area under the curve values of miR-296-5p and miR-28-3p were 0.919 and 0.911, respectively, with high sensitivity and specificity. Kaplan-Meier survival curves showed that patients with GC with high level of miR-296-5p or low level of miR-1236-3p in the serum had the poorest overall survival. COX analysis showed that lymphatic metastasis, high miR-296-5p expression, and low miR-28-3p expression are independent parameters indicating poor prognosis in GC. Conclusion: Our findings indicate that serum miR-296-5p and miR-28-3p levels are potential biomarkers in the diagnosis and prognosis of GC.

Exosomes as a Source of Biomarkers for Gastrointestinal Cancers

Exosomes are small, lipid-bilayer bound extracellular vesicles of 40-160 nanometers in size that carry important information for intercellular communication. Exosomes are produced more by tumor cells than normal cells and carry tumor-specific content, such as DNA, RNA, and proteins, which have been implicated in tumorigenesis, tumor progression, and treatment response. Due to the critical role of exosomes in cancer development and progression, they can be exploited to develop specific biomarkers and therapeutic targets. Since exosomes are present in various biofluids, such as blood, saliva, urine, and peritoneal fluid, they are ideally suited to be developed as liquid biopsy tools for early diagnosis, molecular profiling, disease surveillance, and treatment response monitoring. In the past decade, numerous studies have been published about the functional significance of exosomes in a wide variety of cancers, with a particular focus on exosome-derived RNAs and proteins as biomarkers. In this review, utilizing human studies on exosomes, we highlight their potential as diagnostic, prognostic, and predictive biomarkers in gastrointestinal cancers.

The Emerging Role of Exosomal miRNAs as Biomarkers for Early Cancer Detection: A Comprehensive Literature Review

A significant number of cancer-related deaths are recorded globally each year, despite attempts to cure this illness. Medical science is working to develop new medication therapies as well as to find ways to identify this illness as early as possible, even using noninvasive techniques. Early detection of cancer can greatly aid its treatment. Studies into cancer diagnosis and therapy have recently shifted their focus to exosome (EXO) biomarkers, which comprise numerous RNA and proteins. EXOs are minuscule goblet vesicles that have a width of 30 to 140 nm and are released by a variety of cells, including immune, stem, and tumor cells, as well as bodily fluids. According to a growing body of research, EXOs, and cancer appear to be related. EXOs from tumors play a role in the genetic information transfer between tumor and basal cells, which controls angiogenesis and fosters tumor development and spread. To identify malignant activities early on, microRNAs (miRNAs) from cancers can be extracted from circulatory system EXOs. Specific markers can be used to identify cancer-derived EXOs containing miRNAs, which may be more reliable and precise for early detection. Conventional solid biopsy has become increasingly limited as precision and personalized medicine has advanced, while liquid biopsy offers a viable platform for noninvasive diagnosis and prognosis. Therefore, the use of body fluids such as serum, plasma, urine, and salivary secretions can help find cancer biomarkers using technologies related to EXOs.

Repurposed Drugs in Gastric Cancer

Gastric cancer (GC) is one of the major causes of death worldwide, ranking as the fifth most incident cancer in 2020 and the fourth leading cause of cancer mortality. The majority of GC patients are in an advanced stage at the time of diagnosis, presenting a poor prognosis and outcome. Current GC treatment approaches involve endoscopic detection, gastrectomy and chemotherapy or chemoradiotherapy in an adjuvant or neoadjuvant setting. Drug development approaches demand extreme effort to identify molecular mechanisms of action of new drug candidates. Drug repurposing is based on the research of new therapeutic indications of drugs approved for other pathologies. In this review, we explore GC and the different drugs repurposed for this disease.

Recent Trends and Advancements in the Diagnosis and Management of Gastric Cancer

Gastric cancer is an enigmatic malignancy that has recently been shown to be increasing in incidence globally. There has been recent progress in emerging technologies for the diagnosis and treatment of the disease. Improvements in non-invasive diagnostic techniques with serological tests and biomarkers have led to decreased use of invasive procedures such as endoscopy. A multidisciplinary approach is used to treat gastric cancer, with recent significant advancements in systemic therapies used in combination with cytotoxic chemotherapies. New therapeutic targets have been identified and clinical trials are taking place to assess their efficacy and safety. In this review, we provide an overview of the current and emerging treatment strategies and diagnostic techniques for gastric cancer.

Application progress of liquid biopsy in gastric cancer

Gastric cancer (GC) is one of the most common malignant tumors globally. Guiding the individualized treatment of GC is the focus of research. Obtaining representative biological samples to study the biological characteristics of GC is the focus of diagnosis and treatment of GC. Liquid biopsy technology can use high-throughput sequencing technology to detect biological genetic information in blood. Compared with traditional tissue biopsy, liquid biopsy can determine the dynamic changes of tumor. As a noninvasive auxiliary diagnostic method, liquid biopsy can provide diagnostic and prognostic information concerning the progression of the disease. Liquid biopsy includes circulating tumor cells, circulating tumor DNA, circulating tumor RNA, tumor educated platelets, exosomes, and cytokines. This article describes the classification of liquid biopsy and its application value in the occurrence, development, and therapeutic efficacy of GC.

Current perspectives on clinical use of exosomes as novel biomarkers for cancer diagnosis

Exosomes are a heterogeneous subset of extracellular vesicles (EVs) that biogenesis from endosomes. Besides, exosomes contain a variety of molecular cargoes including proteins, lipids and nucleic acids, which play a key role in the mechanism of exosome formation. Meanwhile, exosomes are involved with physiological and pathological conditions. The molecular profile of exosomes reflects the type and pathophysiological status of the originating cells so could potentially be exploited for diagnostic of cancer. This review aims to describe important molecular cargoes involved in exosome biogenesis. In addition, we highlight exogenous factors, especially autophagy, hypoxia and pharmacology, that regulate the release of exosomes and their corresponding cargoes. Particularly, we also emphasize exosome molecular cargoes as potential biomarkers in liquid biopsy for diagnosis of cancer.

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.

Long non-coding RNA CCL2 promoted gastric cancer function via miR-128/ PARP2 signal pathway

Amounts of studies have revealed long non-coding RNA (lncRNA) was related to the development of gastric cancer. Here, our results suggested the function and regulatory mechanism of CCL2 in gastric cancer. Quantitative polymerase-chain reaction (qPCR) was employed to inspect lncRNA CCL2 and miR-128 expression in normal gastric cell line (GES-1) and tumor cell lines (HGC-27 and MKN-45). The effects of CCL2 and miR-128 were measured via Luciferase reporter test. Western blot was used to check PARP2 protein expression. CCL2 expression and PARP2 protein levels were up-regulated, while miR-128 expression was obviously lower. Meanwhile, CCL2 down-regulating significantly repressed the proliferation, migration, and invasion by regulating miR-128. In addition, we proved miR-128 was a direct target of CCL2 through double luciferase assay and bioinformatics analysis. Moreover, miR-128 markedly inhibited the proliferation, migration, and invasion in gastric cancer. More importantly, miR-128 could reverse the effects of lncRNA CCL2 knocked down. PARP2-si obviously suppressed in gastric cancer proliferation, migration, and invasion. Meanwhile, miR-128 mimic and the knockout of CCL2 distinctly decreased PARP2 protein level. Additionally, luciferase report experiments certificated that PARP2 targeted miR-128, implying PARP2 directly interacted with miR-128 in gastric cancer. More interestingly, the downregulation of PARP could reverse the trend triggered by miR-128 inhibitor in gastric tumor. All over these results showed lncRNA CCL2 played importance of role in gastric tumor via miR-128/PARP2 axis signal pathway. LncRNA CCL2 accelerated gastric cancer progression by regulating miR-128/PARP2 signaling pathway, providing a novel possible strategy for the treatment of gastric cancer.

miR-638 Serves as a Biomarker of 5-Fluorouracil Sensitivity to Neoadjuvant Chemotherapy in Breast Cancer

Purpose

Neoadjuvant chemotherapy (NAC) is widely used to treat breast cancer (BC). The prediction and evaluation of chemotherapy responses remains a significant challenge.

Methods

MicroRNAs (miRNAs) play a crucial role in cancer drug resistance. We used a miRNA microarray and identified that miR-638 is downregulated in chemoresistant cases. However, the exact role of miR-638 and the underlying mechanisms of chemoresistance remain unclear. Using real-time quantitative reverse transcription polymerase chain reaction, we found significant downregulation of miR-638 in chemoresistant patients compared with chemosensitive patients. To explore the function of miR-638, we overexpressed and inhibited miR-638 expression in MDA-MB-231 and MCF-7 cells by transfecting them with miR-638 mimics and miR-638 inhibitor, respectively. Cell proliferation and apoptosis were measured using MTS and flow cytometry, respectively. A minimal patient-derived xenograft (MiniPDX™) model was established to evaluate the chemosensitivity to different drugs.

Results

The results showed that cell proliferation decreased and cell apoptosis increased in cells transfected with the miR-638 mimic, and cell proliferation and apoptosis were reversed with transfection of miR-638 inhibitor compared with the control group. Among patients who received 5-fluorouracil (5-FU), miR-638 expression levels were lower in the chemoresistant group than in the chemosensitive group. The MiniPDX™ model showed that MDA-MB-231 cells overexpressing miR-638 were more susceptible to 5-FU treatment in vivo.

Conclusion

We provided evidence of acquired resistance to 5-FU caused by miR-638 deficiency. Alterations in miR-638 may be used with 5-FU chemotherapy during NAC for BC.

Detecting attomolar concentrations of microRNA related to myelodysplastic syndromes in blood plasma using a novel sandwich assay with nanoparticle release

Microribonucleic acids (miRNAs) are short noncoding ribonucleic acids that have been linked with a multitude of human diseases including lung, breast, and hematological cancers. In this work, we present a novel, extremely sensitive assay for the label-free optical biosensor-based detection of miRNAs, which is based on the oligonucleotide-triggered release of nanoparticles from a sensor surface. We combine this assay (herein referred to as the nanoparticle-release (NPR) assay) with a surface plasmon resonance biosensor and show that the assay is able to enhance the specific sensor response associated with the binding of target miRNA while suppressing the interfering effects caused by the non-specific binding. We apply the assay to the detection of miRNAs related to myelodysplastic syndromes (miR-125b, miR-16) in blood plasma and demonstrate that the assay enables detection of miR-125b with a limit of detection (LOD) of 349 aM (corresponding to the lowest detectable amounts of 419 zmol). The achieved LOD is better by a factor of ∼100 when compared to the conventional nanoparticle-enhanced sandwich assay. Moreover, we demonstrate that the NPR assay may be combined with time-division multiplexing for the multiplexed miRNA detection.

High diagnostic value of miRNAs for NSCLC: quantitative analysis for both single and combined miRNAs in lung cancer

BACKGROUND

MicroRNAs (miRNAs) are good candidates as biomarkers for Lung cancer (LC). The aim of this article is to figure out the diagnostic value of both single and combined miRNAs in LC.

METHODS

Normative meta-analysis was conducted based on PRISMA. We assessed the diagnostic value by calculating the combined sensitivity (Sen), specificity (Spe), positive likelihood ratio (PLR), negative likelihood ratio (NLR) and diagnostic odds ratio (DOR) and the area under the curve (AUC) of single and combined miRNAs for LC and specific subgroups.

RESULTS

A total of 80 qualified studies with a total of 8971 patients and 10758 controls were included. In non-small cell lung carcinoma (NSCLC), we involved 20 single-miRNAs and found their Sen, Spe and AUC ranged from 0.52-0.81, 0.66-0.88, and 0.68-0.90, respectively, specially, miR-19 with the maximum Sen, miR-20 and miR-10 with the highest Spe as well as miR-17 with the maximum AUC. Additionally, we detected miR-21 with the maximum Sen of 0.74 [95%CI: 0.62-0.83], miR-146 with the maximum Spe and AUC of 0.93 [95%CI: 0.79-0.98] and 0.89 [95%CI: 0.86-0.92] for early-stage NSCLC. We also identified the diagnostic power of available panel (miR-210, miR-31 and miR-21) for NSCLC with satisfying Sen, Spe and AUC of 0.82 [95%CI: 0.78-0.84], 0.87 [95%CI: 0.84-0.89] and 0.91 [95%CI: 0.88-0.93], and furtherly constructed 2 models for better diagnosis.

CONCLUSIONS

We identified several single miRNAs and combined groups with high diagnostic power for NSCLC through pooled quantitative analysis, which shows that specific miRNAs are good biomarker candidates for NSCLC and further researches needed.

miR-25 Regulates Gastric Cancer Cell Growth and Apoptosis by Targeting EGR2

Gastric cancer is one of the most common malignancies harmful to human health. The search for effective drugs or gene therapy has aroused the attention of scientists. So far, microRNAs, as small non-coding RNAs, have the potential to be therapeutic targets for cancer. Herein, we found a highly expressed miR-25 in gastric cancer cell. However, the function of miR-25 for gastric cancer cell growth and apoptosis was unknown. Functionally, we used RT-qPCR, western blot, CCK-8, and flow cytometry to detect gastric cancer cell growth and apoptosis. The results indicated that miR-25 promoted gastric cancer cell growth and inhibited their apoptosis. Mechanistically, we found that a gene EGR2 was a potential target gene of miR-25. Further dual-luciferase results supported this prediction. Moreover, knockdown of EGR2 promoted gastric cancer cell growth and inhibited their apoptosis by flow cytometry detection. Altogether, these findings revealed miR-25 as a regulator of gastric cancer cell growth and apoptosis through targeting EGR2.

Unveiling the World of Circulating and Exosomal microRNAs in Renal Cell Carcinoma

Simple Summary

Liquid biopsies have emerged as a new tool for early diagnosis. In renal cell carcinoma, this need is also evident and may represent an improvement in disease management. Hence, in this review we discuss the most updated advances in the assessment of miRNAs in liquid biopsies. Moreover, we explore the potential of circulating or exosome miRNAs in renal cell carcinoma to overcome the tissue biopsies limitations.

Abstract

Renal cell carcinoma is the third most common urological cancer. Despite recent advances, late diagnosis and poor prognosis of advanced-stage disease remain a major problem, entailing the need for novel early diagnosis tools. Liquid biopsies represent a promising minimally invasive clinical tool, providing real-time feedback of tumor behavior and biological potential, addressing its clonal evolution and representing its heterogeneity. In particular, the study of circulating microRNAs and exosomal microRNAs in liquid biopsies experienced an exponential increase in recent years, considering the potential clinical utility and available technology that facilitates implementation. Herein, we provide a systematic review on the applicability of these biomarkers in the context of renal cell carcinoma. Issues such as additional benefit from extracting microRNAs transported in extracellular vesicles, use for subtyping and representation of different histological types, correlation with tumor burden, and prediction of patient outcome are also addressed. Despite the need for more conclusive research, available data indicate that exosomal microRNAs represent a robust minimally invasive biomarker for renal cell carcinoma. Thus, innovative research on microRNAs and novel detection techniques are likely to provide clinically relevant biomarkers, overcome current clinical challenges, and improve patient management.

Recent advances in blood-based and artificial intelligence-enhanced approaches for gastrointestinal cancer diagnosis

Gastrointestinal (GI) cancers are among the most common cancer types and leading causes of cancer-related deaths worldwide. There is a tremendous clinical need for effective early diagnosis for better healthcare of GI cancer patients. In this article, we provide a short overview of the recent advances in GI cancer diagnosis. In the first part, we discuss the applications of blood-based biomarkers, such as plasma circulating cell-free DNA, circulating tumor cells, extracellular vesicles, and circulating cell-free RNA, for cancer liquid biopsies. In the second part, we review the current trends of artificial intelligence (AI) for pathology image and tissue biopsy analysis for GI cancer, as well as deep learning-based approaches for purity assessment of tissue biopsies. We further provide our opinions on the future directions in blood-based and AI-enhanced approaches for GI cancer diagnosis, and we think that these fields will have more intensive integrations with clinical needs in the near future.

Diagnostic value of oncofetal miRNAs in cancers: A comprehensive analysis of circulating miRNAs in pan-cancers and UCB

BACKGROUND

Circulating miRNAs are promising biomarkers for detection of various cancers. As a "developmental" disorder, cancer showed great similarities with embryos.

OBJECTIVE

A comprehensive analysis of circulating miRNAs in umbilical cord blood (UCB) and pan-cancers was conducted to identify circulating miRNAs with potential for cancer detection.

METHODS

A total of 3831 cancer samples (2050 serum samples from 15 types of cancers and 1781 plasma samples from 13 types of cancers) and 248 UCB samples (120 serum and 128 plasma samples) with corresponding NCs from Chinese populations were analyzed via consistent experiment workflow with Exiqon panel followed by multiple-stage validation with qRT-PCR.

RESULTS

Thirty-four serum and 32 plasma miRNAs were dysregulated in at least one type of cancer. Eighteen serum and 16 plasma miRNAs were related with embryos. Among them, 9 serum and 8 plasma miRNAs with consistent expression patterns between pan-cancers and UCB were identified as circulating oncofetal miRNAs. Retrospective analysis confirmed the diagnostic ability of circulating oncofetal miRNAs for specific cancers. And the oncofetal miRNAs were mainly up-regulated in tissues of pan-cancers.

CONCLUSIONS

Our study might serve as bases for the potential application of the non-invasive biomarkers in the future clinical.

Emerging Role of Extracellular Vesicles in Biomarking the Gastrointestinal Diseases

INTRODUCTION

Extracellular vesicles (EVs) play an important role in cell-cell communication and regulation of various cellular functions under physiological and pathophysiological conditions through transferring their cargo to recipient cells. Molecular constituents of EVs are a fingerprinting profile of secreting cells which can be used as promising prognostic, diagnostic, and drug-response biomarkers in clinical settings.

AREAS COVERED

The present study provides a brief introduction about the biology of EVs and reviews methodologies used for EV isolation and characterization as well as high-throughput strategies to analyze EV contents. Furthermore, this review highlights the importance and unique role of EVs in the development and progression of gastrointestinal (GI) diseases, especially GI cancers, and then discusses their potential use, particularly those isolated from body fluids, in diagnosis and prognosis of GI diseases.

EXPERT OPINION

In-depth analysis of EV content can lead to the identification of new potential biomarkers for early diagnosis and prognosis prediction of GI diseases. The use of a more targeted approach by establishing more reproducible and standardized methods to decrease variations and obtain desired EV population as well as revisiting large pools of identified biomarkers and their evaluation in larger patient cohorts can result in the introduction of more reliable biomarkers in clinic.

The distinct roles of exosomes in tumor-stroma crosstalk within gastric tumor microenvironment

Gastric cancer (GC) development is a complex process displaying polytropic cell and molecular landscape within gastric tumor microenvironment (TME). Stromal cells in TME, including fibroblasts, endothelial cells, mesenchymal stem cells, and various immune cells, support tumor growth, metastasis, and recurrence, functioning as the soil for gastric tumorigenesis. Importantly, exosomes secreted by either stromal cells or tumor cells during tumor-stroma crosstalk perform as crucial transporter of agents including RNAs and proteins for cell-cell communication in GC pathogenesis. Therefore, given the distinct roles of exosomes secreted by various cell types in GC TME, increasing evidence has indicated that exosomes present as new biomarkers for GC diagnosis and prognosis and shed light on novel approaches for GC treatment.

Current and potential biomarkers in gastric cancer: a critical review of the literature

Gastric cancer is the fourth most common type of cancer worldwide and the second most lethal. Gastric cancer biomarkers can be used for diagnosis, prediction of sensitivity to treatment, and prognosis. The following search terms were applied to PubMed as of December 2020: 'gastric cancer classification', 'gastric cancer epidemiology', 'cancer metastasis' and 'gastric cancer biomarker'. Only experimental studies were reported in the 'biomarkers' section. Some biomarkers can serve as therapeutic targets for antitumoral drugs. The genes analyzed include E-cadherin, RPRM, XAF1, MINT25, TFF1, p16 and p53. The miRNAs analyzed include miR-18a, miR185-5p, miR-125b and miR-21. Some molecules were associated with metastasis of gastric cancer, specifically those involved with EMT process and tissue degradation.

The Emerging Role of Circ-SHPRH in Cancer

PURPOSE

Circ-SHPRH is a circular RNA that can regulate the expression of target genes by sponging microRNAs (miRNAs) or translating tumor suppressor proteins. Recent studies have suggested that circ-SHPRH may play a role in the development of tumors and cancers. Hence, this paper aimed to review the biological characteristics, molecular mechanisms, and potential clinical significance of circ-SHPRH in a variety of tumors and to evaluate its potential as a new diagnostic and prognostic biomarker.

METHODS

Numerous experiments were performed regarding the abnormal expression of circ-SHPRH in a variety of tumors, including hepatocellular carcinoma, gastric carcinoma, non-small cell lung cancer, osteosarcoma, colorectal cancer, cholangiocarcinoma, pancreatic ductal adenocarcinoma, retinoblastoma, and glioblastoma.

RESULTS

Upregulation of circ-SHPRH reportedly inhibits tumor cell proliferation, migration, and invasion, leading to the inhibition of tumor development. The clinicopathological parameters and the functional characteristics of circ-SHPRH in multiple human tumors and cancers were summarized. Circ-SHPRH functions as a tumor suppressor gene and has great potential as a diagnostic and prognostic biomarker for different types of cancer.

Circulating MicroRNAs in Gastrointestinal Cancer

Simple Summary

The screening methods and therapeutic strategies for gastrointestinal cancer (GIC) have improved, but mortality in GIC patients remains high. Early detection and precise evaluation of GIC are required to further improve treatment outcomes in GIC patients. MicroRNAs (miRNAs), which do not encode proteins, have attracted attention as biomarkers of various diseases. Since the first report revealing the strong correlation between miRNAs and cancer in 2002, numerous studies have illustrated the changes in the expression and the biological and oncological effects of miRNAs in GIC. Furthermore, miRNAs circulating in the blood are reported to be associated with GIC status. These miRNAs are thought to be useful as noninvasive biomarkers because of their stability in blood. Herein, we discuss the potential of miRNAs as noninvasive biomarkers for each type of GIC on the basis of previous reports and describe perspectives for their future application.

Abstract

Gastrointestinal cancer (GIC) is a common disease and is considered to be the leading cause of cancer-related death worldwide; thus, new diagnostic and therapeutic strategies for GIC are urgently required. Noncoding RNAs (ncRNAs) are functional RNAs that are transcribed from the genome but do not encode proteins. MicroRNAs (miRNAs) are short ncRNAs that are reported to function as both oncogenes and tumor suppressors. Moreover, several miRNA-based drugs are currently proceeding to clinical trials for various diseases, including cancer. In recent years, the stability of circulating miRNAs in blood has been demonstrated. This is of interest because these miRNAs could be potential noninvasive biomarkers of cancer. In this review, we focus on circulating miRNAs associated with GIC and discuss their potential as novel biomarkers.

Circulating MicroRNAs in Small-bowel Neuroendocrine Tumors: A Potential Tool for Diagnosis and Assessment of Effectiveness of Surgical Resection

OBJECTIVE

To discover serum-based microRNA (miRNA) biomarkers for small-bowel neuroendocrine tumors (SBNET) to help guide clinical decisions.

BACKGROUND

MiRNAs are small noncoding RNA molecules implicated in the initiation and progression of many cancers. MiRNAs are remarkably stable in bodily fluids, and can potentially be translated into clinically useful biomarkers. Novel biomarkers are needed in SBNET to determine disease aggressiveness, select patients for treatment, detect early recurrence, and monitor response.

METHODS

This study was performed in 3 stages (discovery, validation, and a prospective, longitudinal assessment). Discovery comprised of global profiling of 376 miRNA in sera from SBNET patients (n = 11) versus healthy controls (HCs; n = 3). Up-regulated miRNAs were subsequently validated in additional SBNET (n = 33) and HC sera (n = 14); and then longitudinally after SBNET resection (n = 12), with serial serum sampling (preoperatively day 0; postoperatively at 1 week, 1 month, and 12 months).

RESULTS

Four serum miRNAs (miR-125b-5p, -362-5p, -425-5p and -500a-5p) were significantly up-regulated in SBNET (P < 0.05; fold-change >2) based on multiple normalization strategies, and were validated by RT-qPCR. This combination was able to differentiate SBNET from HC with an area under the curve of 0.951. Longitudinal assessment revealed that miR-125b-5p returned towards HC levels at 1 month postoperatively in patients without disease, whereas remaining up-regulated in those with residual disease (RSD). This was also true at 12 months postoperatively. In addition, miR-362-5p appeared up-regulated at 12 months in RSD and recurrent disease (RCD).

CONCLUSIONS

Our study represents the largest global profiling of serum miRNAs in SBNET patients, and the first to evaluate ongoing serum miRNA expression changes after surgical resection. Serum miR-125b-5p and miR-362-5p have potential to be used to detect RSD/RCD.

Role of Exosomal Non-coding RNAs in Gastric Cancer: Biological Functions and Potential Clinical Applications

Gastric cancer (GC) is one of the most common fatal cancers worldwide. The communication between GC and other cells in the GC microenvironment directly affects GC progression. Recently, exosomes have been revealed as new players in intercellular communication. They play an important role in human health and diseases, including cancer, owing to their ability to carry various bioactive molecules, including non-coding RNAs (ncRNAs). NcRNAs, including micro RNAs, long non-coding RNAs, and circular RNAs, play a significant role in various pathophysiological processes, especially cancer. Increasing evidence has shown that exosomal ncRNAs are involved in the regulation of tumor proliferation, invasion, metastasis, angiogenesis, immune regulation, and treatment resistance in GC. In addition, exosomal ncRNAs have promising potential as diagnostic and prognostic markers for GC. Considering the biocompatibility of exosomes, they can also be used as biological carriers for targeted therapy. This review summarizes the current research progress on exosomal ncRNAs in gastric cancer, focusing on their biological role in GC and their potential as new biomarkers for GC and therapeutics. Our review provides insight into the mechanisms involved in GC progression, which may provide a new point cut for the discovery of new diagnostic markers and therapeutic strategies.

MicroRNA panel in serum reveals novel diagnostic biomarkers for prostate cancer

Purpose

MicroRNAs (miRNAs), which could be stably preserved and detected in serum or plasma, could act as biomarkers in cancer diagnosis. Prostate cancer is the second cancer in males for incidence. This study aimed to establish a miRNA panel in peripheral serum which could act as a non-invasive biomarker helping diagnosing PC.

Methods

A total of 86 PC patients and 86 normal control serum samples were analyzed through a four-stage experimental process using quantitative real-time polymerase chain reaction. Logistic regression method was used to construct a diagnostic model based on the differentially expressed miRNAs in serum. Receiver operating characteristic curves were constructed to evaluate the diagnostic accuracy. We also compared the 3-miRNA panel with previously reported biomarkers and verified in four public datasets. In addition, the expression characteristics of the identified miRNAs were further explored in tissue and serum exosomes samples.

Results

We identified a 3-miRNA signature including up-regulated miR-146a-5p, miR-24-3p and miR-93-5p for PC detection. Areas under the receiver operating characteristic curve of the 3-miRNA panel for the training, testing and external validation phase were 0.819, 0.831 and 0.814, respectively. The identified signature has a very stable diagnostic performance in the large cohorts of four public datasets. Compared with previously identified miRNA biomarkers, the 3-miRNA signature in this study has superior performance in diagnosing PC. What’s more, the expression level of miR-93-5p was also elevated in exosomes from PC samples. However, in PC tissues, none of the three miRNAs showed significantly dysregulated expression.

Conclusions

We established a three-miRNA panel (miR-146a-5p, miR-24-3p and miR-93-5p) in peripheral serum which could act as a non-invasive biomarker helping diagnosing PC.

Recent advances of miRNAs in the development and clinical application of gastric cancer

Gastric cancer (GC) is one of the most common malignant tumors. The mechanism of how GC develops is vague, and therapies are inefficient. The function of microRNAs (miRNAs) in tumorigenesis has attracted the attention from many scientists. During the development of GC, miRNAs function in the regulation of different phenotypes, such as proliferation, apoptosis, invasion and metastasis, drug sensitivity and resistance, and stem-cell-like properties. MiRNAs were evaluated for use in diagnostic and prognostic predictions and exhibited considerable accuracy. Although many problems exist for the application of therapy, current studies showed the antitumor effects of miRNAs. This paper reviews recent advances in miRNA mechanisms in the development of GC and the potential use of miRNAs in the diagnosis and treatment of GC.

A three-microRNA panel in serum as novel biomarker for papillary thyroid carcinoma diagnosis

Background

Accumulating evidence has revealed that circulating microRNAs (miRNAs) can serve as non-invasive biomarkers for cancer diagnosis. This study aimed to identify differentially expressed miRNAs in serum which might become potential biomarkers for non-invasive diagnosis of papillary thyroid carcinoma (PTC).

Methods

The experiment was carried out between 2015 and 2017. In the screening stage, the Exiqon miRNA quantitative real-time polymerase chain reaction (qPCR) panel was applied to select candidate miRNAs. In the following training, testing, and external validation stages, the serum samples of 100 patients and 96 healthy controls (HCs) were analyzed to compare the expression levels of the identified miRNAs. The areas under the receiver operating characteristic curves (AUCs) were calculated to assess the diagnostic value of the identified signature.

Results

Three miRNAs (miR-25-3p, miR-296-5p, and miR-92a-3p) in serum were consistently up-regulated in PTC patients compared with HCs. A three-miRNA panel was constructed by logistic regression analysis and showed better diagnostic performance than a single miRNA for PTC detection. The AUCs of the panel were 0.727, 0.771, and 0.862 for the training, testing, and external validation stage, respectively. Meanwhile, the panel showed stable capability in differentiating PTC patients from patients with benign goiters, with an AUC as high as 0.969. For further exploration, the three identified miRNAs were analyzed in tissue samples (23 PTC vs. 23 HCs) and serum-derived exosomes samples (24 PTC vs. 24 HCs), and the altered expression in the tumor also indicated their close relationship with PTC disease.

Conclusion

We identify a three-miRNA panel in serum which might serve as a promising biomarker for PTC diagnosis.

Comprehensive evaluation of microRNA-10b in digestive system cancers reveals prognostic implication and signaling pathways associated with tumor progression

Background: Digestive system cancers (DSCs) have been recognized to be linked with high morbidity and mortality. Recent studies have reported that microRNA-10b (miR-10b) is abnormally expressed in DSCs and associated with prognosis. However, the inconclusive results and unknown underlying mechanisms promoted us to perform this study. Methods: We systematic searched several databases for eligible studies and conducted quantitative analysis for evidence regarding the associations between miR-10b and survival outcome of DSCs. We also performed a series of bioinformatics analyses to uncover the potential mechanisms. Results: A total of 32 eligible studies with 3392 patients were included. Increased miR-10b expression was linked with unfavorable overall survival (OS) in DSCs (HR=1.72; 95% CI: 1.30-2.27; P <0.001). When stratified by tumor type, the impact of miR-10b overexpression on poor prognosis was observed in colorectal cancer, gastric cancer, hepatocellular carcinoma, and esophageal carcinoma, but not in pancreatic cancer. Subsequently, we predicted the targets of miR-10b and conducted functional enrichment analyses. The results disclosed that miR-10b targets were predominantly enriched in some vital biological terms and pivotal signaling pathways associated with tumor progression including cell cycle, FoxO, proteoglycans, central carbon metabolism, p53, Notch, HIF-1, focal adhesion, AMPK, and pancreatic cancer. Moreover, a protein-protein interaction (PPI) network was also constructed to identify the top ten hub genes and significant modules and demonstrated the underlying interactions among them. Conclusion: Our results indicated that miR-10b could act as a significant biomarker in the prognosis DSCs. However, more research should be performed to test these findings.

Identification of miRNA Signature in Breast Cancer to Predict Neoadjuvant Chemotherapy Response

Background: Chemotherapy failure causes high breast cancer recurrence and poor patient prognosis. Thus, we studied a cohort of novel biomarkers to predict chemotherapeutic response in breast cancer. In this study, miRNA expression profiling was performed on 10 breast cancer punctured specimens sensitive to chemotherapy (MP grade 4, 5) and 10 chemotherapy resistant (MP grade 1). Differentially expressed miRNAs were verified by qRT-PCR in 60 initial samples, 59 validated samples and 71 independent samples. A miRNA signature was generated using a Logistic regression model. A receiver operating characteristic (ROC) test was used to assess specificity and sensitivity of single miRNA and miRNA signature. Target genes regulated by miRNAs and their involved signaling pathways were analyzed using GO enrichment and KEGG software. MiRNAs expression were separately compared with ER, PR, HER2 immunohistochemical staining and different drugs. qRT-PCR showed that the high expression of miR-23a-3p, miR-200c-3p, miR-214-3p and the low expression of miR-451a and miR-638 were closely related to chemoresistance. According to the formula for calculating the drug resistance risk, patients in the high-risk group were more likely to develop chemotherapy resistance than the low-risk group. Bioinformatics analysis showed that 5 miRNAs and target genes are mainly involved in p53, ubiquitin-mediated proteolysis, mTOR, Wnt, cells skeletal protein regulation, cell adhesion and ErbB signaling pathways. miR-451a expression was associated with ER, HER-2 status and anthracyclines. A miRNA signature of chemotherapeutic response may be clinically valuable for improving current chemotherapy regimens of individual treatment for patients with breast cancer.

The role and application of small extracellular vesicles in gastric cancer

Gastric cancer (GC) is a common tumour that affects humans worldwide, is highly malignant and has a poor prognosis. Small extracellular vesicles (sEVs), especially exosomes, are nanoscale vesicles released by various cells that deliver bioactive molecules to recipient cells, affecting their biological characteristics, changing the tumour microenvironment and producing long-distance effects. In recent years, many studies have clarified the mechanisms by which sEVs function with regard to the initiation, progression, angiogenesis, metastasis and chemoresistance of GC. These molecules can function as mediators of cell-cell communication in the tumour microenvironment and might affect the efficacy of immunotherapy. Due to their unique physiochemical characteristics, sEVs show potential as effective antitumour vaccines as well as drug carriers. In this review, we summarize the roles of sEVs in GC and highlight the clinical application prospects in the future.

MicroRNA-653-5p Promotes Gastric Cancer Proliferation and Metastasis by Targeting the SOCS6-STAT3 Pathway

MicroRNAs (miRNAs) are emerging as significant regulators of the tumorigenesis of gastric cancer (GC), and may be effective biomarkers for diagnosis, prognosis, and therapeutic targeting for GC. In this study, miR-653-5p was found to be significantly upregulated in GC tissues, serum, and cell lines and was strongly associated with poor prognosis in patients with GC. Furthermore, miR-653-5p promoted GC cell proliferation and metastasis in vivo and in vitro. Suppressor of cytokine signaling 6 (SOCS6) was directly targeted by miR-653-5p, and SOCS6 attenuated miR-653-5p-mediated GC cell growth, migration, and invasion. In addition, SOCS6-mediated inactivation of the Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling pathway was also reversed by the administration of miR-653-5p. The findings from this study support a novel regulatory axis between miR-653-5p, SOCS6, and JAK2/STAT3 that may be a target for diagnosis and therapeutic intervention for GC.

Plasmonic Alloys Reveal a Distinct Metabolic Phenotype of Early Gastric Cancer

Gastric cancer (GC) is a multifactorial process, accompanied by alterations in metabolic pathways. Non-invasive metabolic profiling facilitates GC diagnosis at early stage leading to an improved prognostic outcome. Herein, mesoporous PdPtAu alloys are designed to characterize the metabolic profiles in human blood. The elemental composition is optimized with heterogeneous surface plasmonic resonance, offering preferred charge transfer for photoinduced desorption/ionization and enhanced photothermal conversion for thermally driven desorption. The surface structure of PdPtAu is further tuned with controlled mesopores, accommodating metabolites only, rather than large interfering compounds. Consequently, the optimized PdPtAu alloy yields direct metabolic fingerprints by laser desorption/ionization mass spectrometry in seconds, consuming 500 nL of native plasma. A distinct metabolic phenotype is revealed for early GC by sparse learning, resulting in precise GC diagnosis with an area under the curve of 0.942. It is envisioned that the plasmonic alloy will open up a new era of minimally invasive blood analysis to improve the surveillance of cancer patients in the clinical setting.

Novel Biomarkers in the Diagnosis of Benign and Malignant Gastrointestinal Diseases

BACKGROUND

Various noninvasive biomarkers have been used in the diagnosis, prognosis, and treatment of different gastrointestinal (GI) diseases for years. Novel technological developments and profound perception of molecular processes related to GI diseases over the last decade have allowed researchers to evaluate genetic, epigenetic, and many other potential molecular biomarkers in different diseases and clinical settings. Here, we present a review of recent and most relevant articles in order to summarize major findings on novel biomarkers in the diagnosis of benign and malignant GI diseases.

SUMMARY

Genetic variations, noncoding RNAs (ncRNAs), cell-free DNA (cfDNA), and microbiome-based biomarkers have been extensively analyzed as potential biomarkers in benign and malignant GI diseases. Multiple single-nucleotide polymorphisms have been linked with a number of GI diseases, and these observations are further being used to build up disease-specific genetic risk scores. Micro-RNAs and long ncRNAs have a large potential as noninvasive biomarkers in the management of inflammatory bowel diseases and GI tumors. Altered microbiome profiles were observed in multiple GI diseases, but most of the findings still lack translational clinical application. As of today, cfDNA appears to be the most potent biomarker for early detection and screening of GI cancers. Key Messages: Novel noninvasive molecular biomarkers show huge potential as useful tools in the diagnostics and management of different GI diseases. However, the use of these biomarkers in real-life clinical practice still remains limited, and further large studies are needed to elucidate the ultimate role of these potential noninvasive clinical tools.

Identifying Novel Biomarkers Ready for Evaluation in Low-Prevalence Populations for the Early Detection of Upper Gastrointestinal Cancers: A Systematic Review

Introduction

Detecting upper gastrointestinal (GI) cancers in primary care is challenging, as cancer symptoms are common, often non-specific, and most patients presenting with these symptoms will not have cancer. Substantial investment has been made to develop biomarkers for cancer detection, but few have reached routine clinical practice. We aimed to identify novel biomarkers for upper GI cancers which have been sufficiently validated to be ready for evaluation in low-prevalence populations.

Methods

We systematically searched MEDLINE, Embase, Emcare, and Web of Science for studies published in English from January 2000 to October 2019 (PROSPERO registration CRD42020165005). Reference lists of included studies were assessed. Studies had to report on second measures of diagnostic performance (beyond discovery phase) for biomarkers (single or in panels) used to detect pancreatic, oesophageal, gastric, and biliary tract cancers. We included all designs and excluded studies with less than 50 cases/controls. Data were extracted on types of biomarkers, populations and outcomes. Heterogeneity prevented pooling of outcomes.

Results

We identified 149 eligible studies, involving 22,264 cancer cases and 49,474 controls. A total of 431 biomarkers were identified (183 microRNAs and other RNAs, 79 autoantibodies and other immunological markers, 119 other proteins, 36 metabolic markers, 6 circulating tumour DNA and 8 other). Over half (n = 231) were reported in pancreatic cancer studies. Only 35 biomarkers had been investigated in at least two studies, with reported outcomes for that individual marker for the same tumour type. Apolipoproteins (apoAII-AT and apoAII-ATQ), and pepsinogens (PGI and PGII) were the most promising biomarkers for pancreatic and gastric cancer, respectively.

Conclusion

Most novel biomarkers for the early detection of upper GI cancers are still at an early stage of matureness. Further evidence is needed on biomarker performance in low-prevalence populations, in addition to implementation and health economic studies, before extensive adoption into clinical practice can be recommended.

Electronic Supplementary Material

The online version of this article (10.1007/s12325-020-01571-z) contains supplementary material, which is available to authorized users.

Investigation of microRNA-10b values for the discrimination of metastasis due to melanoma

Background:

Melanoma is one of the most invasive cutaneous cancers with characteristics such as rapid progression and distant metastasis. The early diagnosis and staging of melanoma can help better manage the patients. The current study is aimed to assess the values of microRNA-10b (miRNA-10b) in the discrimination of metastatic melanomas.

Materials and Methods:

The current cross-sectional study has been conducted on forty patients diagnosed with melanoma since 2011. Cell culture of melanoma cell lines derived from the cancerous tissue, including WM115, BLM, K1735, WM793, and A375M, was cultured. In order to assess miRNA-10b levels, the real-time polymerase chain reaction was utilized. The absence (n = 20)/presence (n = 20) of metastasis was diagnosed with chest computed tomography or chest X-ray. The values of miRNA-10b for the discrimination of metastasis incidence were assessed.

Results:

The demographic characteristics, including age and gender of the metastatic and nonmetastatic patients, were similar (P > 0.05). The specimen cultures were positive for miRNA-10b in 14 (35%) of the metastatic cases versus 4 (20%) of the nonmetastatic ones (P = 0.004). The quantitative analysis of miR-2b revealed significantly higher levels in metastatic cases (−1.59 ± 1.13 in metastatic vs. −0.16 ± 0.67 in nonmetastatic cases; P = 0.001). The measured area under the curve for the value of miRNA-10b was 0.923 (P < 0.001; 95% confidence interval: 0.811–1) with sensitivity and specificity of 100% and 94.4%.

Conclusion:

Based on this study, metastatic melanoma was associated with elevated levels of miRNA-10b. This marker had the sensitivity and specificity of 100% and 94.4% for the discrimination of metastatic melanoma from nonmetastatic ones.

MiR-4310 induced by SP1 targets PTEN to promote glioma progression

Background

miRNAs have been reported to be involved in multiple biological processes of gliomas. Here, we aimed to analyze miR-4310 and its correlation genes involved in the progression of human glioma.

Methods

miR-4310 expression levels were examined in glioma and non-tumor brain (NB) tissues. The molecular mechanisms of miR-4310 expression and its effects on cell proliferation, migration, and invasion were explored using 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide, Transwell chamber, Boyden chamber, and western blot analyses, as well as its effect on tumorigenesis was explored in vivo in nude mice. The relationships between miR-4310, SP1, phosphatase, and tensin homolog (PTEN) were explored using chromatin immunoprecipitation, agarose gel electrophoresis, electrophoresis mobility shift, and dual-luciferase reporter gene assays.

Results

miR-4310 expression was upregulated in glioma tissues compared to that in NB tissues. Overexpressed miR-4310 promoted glioma cell proliferation, migration, and invasion in vitro, as well as tumorigenesis in vivo. The inhibition of miR-4310 expression was sufficient to reverse these results. Mechanistic analyses revealed that miR-4310 promoted glioma progression through the PI3K/AKT pathway by targeting PTEN. Additionally, SP1 induced the expression of miR-4310 by binding to its promoter region.

Conclusion

miR-4310 promotes the progression of glioma by targeting PTEN and activating the PI3K/AKT pathway; meanwhile, the expression of miR-4310 was induced by SP1.

Non-Coding RNAs: Uncharted Mediators of Thyroid Cancer Pathogenesis

Thyroid cancer is the most prevalent malignancy of the endocrine system and the ninth most common cancer globally. Despite the advances in the management of thyroid cancer, there are critical issues with the diagnosis and treatment of thyroid cancer that result in the poor overall survival of undifferentiated and metastatic thyroid cancer patients. Recent studies have revealed the role of different non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) that are dysregulated during thyroid cancer development or the acquisition of resistance to therapeutics, and may play key roles in treatment failure and poor prognosis of the thyroid cancer patients. Here, we systematically review the emerging roles and molecular mechanisms of ncRNAs that regulate thyroid tumorigenesis and drug response. We then propose the potential clinical implications of ncRNAs as novel diagnostic and prognostic biomarkers for thyroid cancer.

MicroRNA in Gastric Cancer Development: Mechanisms and Biomarkers

Gastric cancer (GC) is one of the most common and difficult diseases to treat. The study of signaling pathway regulation by microRNA provides information on the mechanisms of GC development and is the basis for biomarker creation. In this study, a circuit of microRNA interactions with signaling pathways was constructed. The microRNAs, associated with metastasis and chemoresistance, are described. In most cases, microRNAs in GC regulate the Wnt/β-catenin, PI3K/AKT/mTOR, RAS/RAF/ERK/MAPK, NF-kB, TGF-β, and JAK/STAT pathways. Part of the microRNA acts on several target genes that function in different pathways. This often leads to an intensification of the induced processes. MicroRNAs have also been described that have the opposite effect on different pathways, causing different functional consequences. By acting on several target genes, or genes associated with several pathways, microRNAs can function in a signaling network. MicroRNAs associated with metastasis most often interact with the Wnt/β-catenin pathway. MicroRNAs affecting chemoresistance, in most cases, affect the regulators of apoptosis and are associated with the PI3K/AKT/mTOR pathway. The characteristics of microRNAs proposed as candidates for GC biomarkers were analyzed. The currently developed diagnostic and prognostic panels of microRNAs are also considered.

EVs as Potential New Therapeutic Tool/Target in Gastrointestinal Cancer and HCC

For more than a decade, extracellular vesicles (EVs) have been in focus of science. Once thought to be an efficient way to eliminate undesirable cell content, EVs are now well-accepted as being an important alternative to cytokines and chemokines in cell-to-cell communication route. With their cargos, mainly consisting of functional proteins, lipids and nucleic acids, they can activate signalling cascades and thus change the phenotype of recipient cells at local and systemic levels. Their substantial role as modulators of various physiological and pathological processes is acknowledged. Importantly, more and more evidence arises that EVs play a pivotal role in many stages of carcinogenesis. Via EV-mediated communication, tumour cells can manipulate cells from host immune system or from the tumour microenvironment, and, ultimately, they promote tumour progression and modulate host immunity towards tumour's favour. Additionally, the role of EVs in modulating resistance to pharmacological and radiological therapy of many cancer types has become evident lately. Our understanding of EV biology and their role in cancer promotion and drug resistance has evolved considerably in recent years. In this review, we specifically discuss the current knowledge on the association between EVs and gastrointestinal (GI) and liver cancers, including their potential for diagnosis and treatment.

Non-Invasive Early Molecular Detection of Gastric Cancers

Gastric cancer (GC) is a significant source of global cancer death with a high mortality rate, because the majority of patients with GC are diagnosed at a late stage, with limited therapeutic choices and poor outcomes. Therefore, development of minimally invasive or noninvasive biomarkers which are specific to GC is crucially needed. The latest advancements in the understanding of GC molecular landscapes and molecular biological methods have accelerated attempts to diagnose GC at an early stage. Body fluids, including peripheral blood, saliva, gastric juice/wash, urine, and others, can be a source of biomarkers, offering new methods for the early detection of GC. Liquid biopsy-based methods using circulating sources of cancer nucleic acids could also be considered as alternative strategies. Moreover, investigating gastric juices/washes could represent an alternative for the detection of GC via invasive biopsy. This review summarizes recently reported biomarkers based on DNA methylation, microRNA, long noncoding RNA, circular RNA, or extracellular vesicles (exosomes) for the detection of GC. Although the majority of studies have been conducted to detect these alterations in advanced-stage GC and only a few in population studies or early-stage GC, some biomarkers are potentially valuable for the development of novel approaches for an early noninvasive detection of GC.