A novel urinary microRNA biomarker panel for detecting gastric cancer

Urinary dipeptidase 1 and trefoil factor 1 are promising biomarkers for early diagnosis of colorectal cancer

BACKGROUND

Currently utilized serum tumor markers and fecal immunochemical tests do not have sufficient diagnostic power for colorectal cancer (CRC) due to their low sensitivities. To establish non-invasive urinary protein biomarkers for early CRC diagnosis, we performed stepwise analyses employing urine samples from CRCs and healthy controls (HCs).

METHODS

Among 474 urine samples, 363 age- and sex-matched participants (188 HCs, 175 stage 0-III CRCs) were randomly divided into discovery (16 HCs, 16 CRCs), training (110 HCs, 110 CRCs), and validation (62 HCs, 49 CRCs) cohorts.

RESULTS

Of the 23 urinary protein candidates comprehensively identified from mass spectrometry in the discovery cohort, urinary levels of dipeptidase 1 (uDPEP1) and Trefoil factor1 (uTFF1) were the two most significant diagnostic biomarkers for CRC in both training and validation cohorts using enzyme-linked immunosorbent assays. A urinary biomarker panel comprising uDPEP1 and uTFF1 significantly distinguished CRCs from HCs, showing area under the curves of 0.825-0.956 for stage 0-III CRC and 0.792-0.852 for stage 0/I CRC. uDPEP1 and uTFF1 also significantly distinguished colorectal adenoma (CRA) patients from HCs, with uDPEP1 and uTFF1 increasing significantly in the order of HCs, CRA patients, and CRC patients. Moreover, expression levels of DPEP1 and TFF1 were also significantly higher in the serum and tumor tissues of CRC, compared to HCs and normal tissues, respectively.

CONCLUSIONS

This study established a promising and non-invasive urinary protein biomarker panel, which enables the early detection of CRC with high sensitivity.

MicroRNAs in Helicobacter pylori-infected gastric cancer: Function and clinical application

Gastric cancer (GC) is the leading cause of cancer-related death worldwide, and it is associated with a combination of genetic, environmental, and microbial risk factors. Helicobacter pylori (H. pylori) is classified as a type I carcinogen, however, the exact regulatory mechanisms underlying H. pylori-induced GC are incompletely defined. MicroRNAs (miRNAs), one of small non-coding RNAs, negatively regulate gene expression through binding to their target genes. Dysregulation of miRNAs is crucial in human cancer. A noteworthy quantity of aberrant miRNAs induced by H. pylori through complex regulatory networks have been identified. These miRNAs substantially affect genetic instability, cell proliferation, apoptosis, invasion, metastasis, autophagy, chemoresistance, and the tumor microenvironment, leading to GC development and progression. Importantly, some H. pylori-associated miRNAs hold promise as therapeutic tools and biomarkers for GC prevention, diagnosis, and prognosis. Nonetheless, clinical application of miRNAs remains in its infancy with multiple issues, including sensitivity and specificity, stability, reliable delivery systems, and off-target effects. Additional research on the specific molecular mechanisms and more clinical data are still required. This review investigated the biogenesis, regulatory mechanisms, and functions of miRNAs in H. pylori-induced GC, offering novel insights into the potential clinical applications of miRNA-based therapeutics and biomarkers.

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.

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.

Liquid Biopsy: An Emerging Diagnostic, Prognostic, and Predictive Tool in Gastric Cancer

Liquid biopsy, a minimally invasive procedure that causes minimal pain and complication risks to patients, has been extensively studied for cancer diagnosis and treatment. Moreover, it facilitates comprehensive quantification and serial assessment of the whole-body tumor burden. Several biosources obtained through liquid biopsy have been studied as important biomarkers for establishing early diagnosis, monitoring minimal residual disease, and predicting the prognosis and response to treatment in patients with cancer. Although the clinical application of liquid biopsy in gastric cancer is not as robust as that in other cancers, biomarker studies using liquid biopsy are being actively conducted in patients with gastric cancer. Herein, we aimed to review the role of various biosources that can be obtained from patients with gastric cancer through liquid biopsies, such as blood, saliva, gastric juice, urine, stool, peritoneal lavage fluid, and ascites, by dividing them into cellular and acellular components. In addition, we reviewed previous studies on the diagnostic, prognostic, and predictive biomarkers for gastric cancer using liquid biopsy and discussed the limitations of liquid biopsy and the challenges to overcome these limitations in patients with gastric cancer.

MiR-200b categorizes patients into pancreas cystic lesion subgroups with different malignant potential

Extracellular vesicles (EV) carry their cargo in a membrane protected form, however, their value in early diagnostics is not well known. Although pancreatic cysts are heterogeneous, they can be clustered into the larger groups of pseudocysts (PC), and serous and mucinous pancreatic cystic neoplasms (S-PCN and M-PCN, respectively). In contrast to PCs and S-PCNs, M-PCNs may progress to malignant pancreatic cancers. Since current diagnostic tools do not meet the criteria of high sensitivity and specificity, novel methods are urgently needed to differentiate M-PCNs from other cysts. We show that cyst fluid is a rich source of EVs that are positive and negative for the EV markers CD63 and CD81, respectively. Whereas we found no difference in the EV number when comparing M-PCN with other pancreatic cysts, our EV-based biomarker identification showed that EVs from M-PCNs had a higher level of miR-200b. We also prove that not only EV-derived, but also total cyst fluid miR-200b discriminates patients with M-PCN from other pancreatic cysts with a higher sensitivity and specificity compared to other diagnostic methods, providing the possibility for clinical applications. Our results show that measuring miR-200b in cyst fluid-derived EVs or from cyst fluid may be clinically important in categorizing patients.

Recent progress in biomarker-based diagnostics of Helicobacter pylori, gastric cancer-causing bacteria

The progression of any disease and its outcomes depend on the complicated interaction between pathogens, host and environmental factors. Thus, complete knowledge of bacterial toxins involved in pathogenesis is necessary to develop diagnostic methods and alternative therapies, including vaccines. This review summarizes recently employed biomarkers to diagnose the presence of Helicobacter pylori bacteria. The authors review distinct types of disease-associated biomarkers such as urease, DNA, miRNA, aptamers and bacteriophages that can be utilized as targets to detect Helicobacter pylori and, moreover, gastric cancer in its early stage. A detailed explanation is also given in the context of the recent utilization of these biomarkers in the development of a highly specific and sensitive biosensing platform.

Site-specific protein biomarkers in gastric cancer: a comprehensive review of novel biomarkers and clinical applications

INTRODUCTION

Gastric cancer (GC) is the fifth most common cancer and the fourth leading cause of cancer-related death worldwide, thus representing a significant global health burden. Early detection and monitoring of GC are essential to improve patient outcomes. While traditional cancer biomarkers such as carcinoembryonic antigen, carbohydrate antigen (CA) 19-9, and CA 72-4 are widely used, their limited sensitivity and specificity necessitate the exploration of alternative biomarkers.

AREAS COVERED

This review comprehensively analyzes the landscape of GC protein biomarkers identified from 2019 to 2022, with a focus on tissue, blood, urine, saliva, gastric juice, ascites, and exhaled breath as sample sources. We address the potential clinical applications of these biomarkers in early diagnosis, monitoring recurrence, and predicting survival and therapeutic response of GC patients.

EXPERT OPINION

The discovery of novel protein biomarkers holds great promise for improving the clinical management of GC. However, further validation in large, diverse cohorts is needed to establish the clinical utility of these biomarkers. Integrating these biomarkers with existing diagnostic and monitoring approaches will likely lead to improved personalized treatment plans and patient outcomes.

The Comprehensive Analysis of Specific Proteins as Novel Biomarkers Involved in the Diagnosis and Progression of Gastric Cancer

Gastric cancer (GC) cases are predicted to rise by 2040 to approximately 1.8 million cases, while GC-caused deaths to 1.3 million yearly worldwide. To change this prognosis, there is a need to improve the diagnosis of GC patients because this deadly malignancy is usually detected at an advanced stage. Therefore, new biomarkers of early GC are sorely needed. In the present paper, we summarized and referred to a number of original pieces of research concerning the clinical significance of specific proteins as potential biomarkers for GC in comparison to well-established tumor markers for this malignancy. It has been proved that selected chemokines and their specific receptors, vascular endothelial growth factor (VEGF) and epidermal growth factor receptor (EGFR), specific proteins such as interleukin 6 (IL-6) and C-reactive protein (CRP), matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs), a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS), as well as DNA- and RNA-based biomarkers, and c-MET (tyrosine-protein kinase Met) play a role in the pathogenesis of GC. Based on the recent scientific literature, our review indicates that presented specific proteins are potential biomarkers in the diagnosis and progression of GC as well as might be used as prognostic factors of GC patients' survival.

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.

Evaluation of the role of kefir in management of non-alcoholic steatohepatitis rat model via modulation of NASH linked mRNA-miRNA panel

Non-alcoholic steatohepatitis (NASH) is the clinically aggressive variant of non-alcoholic fatty liver disease. Hippo pathway dysregulation can contribute to NASH development and progression. The use of probiotics is effective in NASH management. Our aim is to investigate the efficacy of kefir Milk in NASH management via modulation of hepatic mRNA-miRNA based panel linked to NAFLD/NASH Hippo signaling and gut microbita regulated genes which was identified using bioinformatics tools. Firstly, we analyzed mRNAs (SOX11, SMAD4 and AMOTL2), and their epigenetic regulator (miR-6807) followed by validation of target effector proteins (TGFB1, IL6 and HepPar1). Molecular, biochemical, and histopathological, analyses were used to evaluate the effects of kefir on high sucrose high fat (HSHF) diet -induced NASH in rats. We found that administration of Kefir proved to prevent steatosis and development of the inflammatory component of NASH. Moreover, Kefir improved liver function and lipid panel. At the molecular level, kefir down-regulated the expression of miR 6807-5p with subsequent increase in the expression of SOX 11, AMOTL2 associated with downregulated SMAD4, resulting in reduction in the expression of the inflammatory and fibrotic markers, IL6 and TGF-β1 in the treated and prophylactic groups compared to the untreated rats. In conclusion, Kefir suppressed NASH progression and improved both fibrosis and hepatic inflammation. The produced effect was correlated with modulation of SOX11, SMAD4 and AMOTL2 mRNAs) - (miR-6807-5p) - (TGFB, IL6 and, HepPar1) expression.

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.

Microfluidics-Based Urine Biopsy for Cancer Diagnosis: Recent Advances and Future Trends

Urine biopsy, allowing for the detection, analysis and monitoring of numerous cancer-associated urinary biomarkers to provide insights into cancer occurrence, progression and metastasis, has emerged as an attractive liquid biopsy strategy with enormous advantages over traditional tissue biopsy, such as noninvasiveness, large sample volume, and simple sampling operation. Microfluidics enables precise manipulation of fluids in a tiny chip and exhibits outstanding performance in urine biopsy owing to its minimization, low cost, high integration, high throughput and low sample consumption. Herein, we review recent advances in microfluidic techniques employed in urine biopsy for cancer detection. After briefly summarizing the major urinary biomarkers used for cancer diagnosis, we provide an overview of the typical microfluidic techniques utilized to develop urine biopsy devices. Some prospects along with the major challenges to be addressed for the future of microfluidic-based urine biopsy are also discussed.

A Novel Urinary miRNA Biomarker for Early Detection of Colorectal Cancer

Simple Summary

Early diagnosis is critically important to achieve life-saving therapy for colorectal cancer (CRC). Since colonoscopy is not suitable as a screening method for CRC due to its invasiveness and high-cost, reliable and non-invasive diagnostic biomarkers are hopeful for CRC. In this case-control study, we established completely non-invasive, novel urinary microRNA (miRNA) biomarker panel combining miR-129-1-3p and miR-566 for the diagnosis of CRC. In the independent age- and sex-matched three cohorts comprising 415 participants, urinary levels of these miRNAs were consistently elevated in the CRC group compared to the healthy controls. Notably, the panel of combining miR-129-1-3p and miR-566 revealed an AUC of 0.845 for stage 0/I CRC that can be treated with endoscopic resection.

Abstract

Since noninvasive biomarkers as an alternative to invasive colonoscopy to detect colorectal cancer (CRC) are desired, we conducted this study to determine the urinary biomarker consisting of microRNAs (miRNAs). In total, 415 age- and sex-matched participants, including 206 patients with CRC and 209 healthy controls (HCs), were randomly divided into three groups: (1) the discovery cohort (CRC, n = 3; HC, n = 6); (2) the training cohort (140 pairs); and (3) the validation cohort (63 pairs). Among 11 urinary miRNAs with aberrant expressions between the two groups, miR-129-1-3p and miR-566 were significantly independent biomarkers that detect CRC. The panel consisting of two miRNAs could distinguish patients with CRC from HC participants with an area under the curve (AUC) = 0.811 in the training cohort. This panel showed good efficacy with an AUC = 0.868 in the validation cohort. This urinary biomarker combining miR-129-1-3p and miR-566 could detect even stage 0/I CRC effectively with an AUC = 0.845. Moreover, the expression levels of both miR-129-1-3p and miR-566 were significantly higher in primary tumor tissues than in adjacent normal tissue. Our established novel biomarker consisting of urinary miR-129-1-3p and miR-566 enables noninvasive and early detection of CRC.

A four-miRNA signature in serum as a biomarker for bladder cancer diagnosis

BACKGROUND

Urinary bladder cancer (BCa) is globally the 10th most frequent cancer. As a novel diagnostic tool, miRNA in serum screening is non-invasive. This project aimed to determine particular serum miRNAs as novel biomarkers for diagnosing urinary BCa.

METHODS

We designed a three-phase study with 122 healthy controls (HCs) and 132 BCa patients. The 30 miRNAs' expressions in serum from HCs and BCa patients were detected during the screening phase. The miRNAs with the most dysregulation were tested in the training (HCs vs. BCa, 30 each) and validation (80 HCs vs. 82 BCa) phase further. The diagnostic ability of these candidate miRNAs was estimated by the receiver operating characteristic (ROC) curves as well as the area under the ROC curve (AUC). The miRNAs' target genes and their annotations to functions were predicted utilizing bioinformatic assays.

RESULTS

Six serum miRNAs (miR-124-3p, miR-182-5p, miR-1-3p, miR-196a-5p, miR-23b-3p and miR-34a-5p) had significantly different expression between BCa patients and HCs in the training and validation phase. The four-microRNA panel improved the diagnostic value, with AUC =0.985. The result of bioinformatic analysis showed that these miRNAs' target genes in the panel may be related to the MAPK signaling pathway in bladder cancer.

CONCLUSIONS

Our study identified a four-miRNA panel that is a non-invasive new biomarker for diagnosing BCa.

miR-6807-5p Inhibited the Odontogenic Differentiation of Human Dental Pulp Stem Cells Through Directly Targeting METTL7A

Background: Tooth tissue regeneration mediated by mesenchymal stem cells (MSCs) has become the most ideal treatment. Although the known regulatory mechanism and some achievements have been discovered, directional differentiation cannot effectively induce regeneration of tooth tissue. In this study, we intended to explore the function and mechanism of miR-6807-5p and its target gene METTL7A in odontogenic differentiation.

Methods: In this study, human dental pulp stem cells (DPSCs) were used. Alkaline phosphatase (ALP), Alizarin red staining (ARS), and calcium ion quantification were used to detect the odontogenic differentiation of miR-6807-5p and METTL7A. Real-time RT-PCR, western blot, dual-luciferase reporter assay, and pull-down assay with biotinylated miRNA were used to confirm that METTL7A was the downstream gene of miR-6807-5p. Protein mass spectrometry and co-immunoprecipitation (Co-IP) were used to detect that SNRNP200 was the co-binding protein of METTL7A.

Results: After mineralized induction, the odontogenic differentiation was enhanced in the miR-6807-5p-knockdown group and weakened in the miR-6807-5p-overexpressed group compared with the control group. METTL7A was the downstream target of miR-6807-5p. After mineralized induction, the odontogenic differentiation was weakened in the METTL7A-knockdown group and enhanced in the METTL7A-overexpressed group compared with the control group. SNRNP200 was the co-binding protein of METTL7A. The knockdown of SNRNP200 inhibited the odontogenic differentiation of DPSCs.

Conclusion: This study verified that miR-6807-5p inhibited the odontogenic differentiation of DPSCs. The binding site of miR-6807-5p was the 3′UTR region of METTL7A, which was silenced by miR-6807-5p. METTL7A promoted the odontogenic differentiation of DPSCs. SNRNP200, a co-binding protein of METTL7A, promoted the odontogenic differentiation of DPSCs.

Urinary estrogen metabolites and gastric cancer risk among postmenopausal women

BACKGROUND

The overall incidence of gastric cancer in women is half that in men for most global populations. Sex hormone pathways may be involved in carcinogenesis and estrogens have been postulated to protect women against gastric cancer.

AIM

To evaluate associations of gastric cancer with estrogen metabolites in postmenopausal women.

METHODS AND RESULTS

We performed an analysis of 233 gastric cancer cases and 281 age-matched controls from three prospective cohorts and two case-control studies of early-stage gastric cancer, mainly conducted in high-risk Asian populations. Fifteen estrogen-parent (estrone and estradiol) and -metabolite analytes (2-hydroxyestrone, 2-hydroxyestradiol, 2-hydroxyestrone-3-methyl ether, 4-hydroxyestrone; 4-methoxyestrone, 4-methoxyestradiol, 2-methoxyestrone, 2-methoxyestradiol, estriol, 16α-hydroxyestrone, 16-ketoestradiol, 16-epiestriol, and 17-epiestriol) were measured in spot urines using liquid chromatography-tandem mass spectrometry. Odds ratios for association with each marker were estimated by logistic regression. Heterogeneity was assessed by Cochran's Q test. Study-specific odds ratios were pooled by fixed-effects meta-analysis. Urinary levels of estrogen-related molecules were not associated with gastric cancer (adjusted odds ratios ranged from 0.87 to 1.27; p-values >.05), with low between-study heterogeneity (p-values >.1) for all but two metabolites (2-hydroxyestrone-3-methyl ether and 2-methoxyestradiol).

CONCLUSION

To date, this is the first comprehensive assessment of endogenous estrogens with gastric cancer risk in women. Estrogens do not appear to have an etiologic role in gastric cancer risk among postmenopausal women. Given the complex network of sex steroid hormones and their extreme variation over the lifespan, further evaluation of this hypothesis is warranted.

Small extracellular vesicles in cancer

Extracellular vesicles (EV) are lipid-bilayer enclosed vesicles in submicron size that are released from cells. A variety of molecules, including proteins, DNA fragments, RNAs, lipids, and metabolites can be selectively encapsulated into EVs and delivered to nearby and distant recipient cells. In tumors, through such intercellular communication, EVs can regulate initiation, growth, metastasis and invasion of tumors. Recent studies have found that EVs exhibit specific expression patterns which mimic the parental cell, providing a fingerprint for early cancer diagnosis and prognosis as well as monitoring responses to treatment. Accordingly, various EV isolation and detection technologies have been developed for research and diagnostic purposes. Moreover, natural and engineered EVs have also been used as drug delivery nanocarriers, cancer vaccines, cell surface modulators, therapeutic agents and therapeutic targets. Overall, EVs are under intense investigation as they hold promise for pathophysiological and translational discoveries. This comprehensive review examines the latest EV research trends over the last five years, encompassing their roles in cancer pathophysiology, diagnostics and therapeutics. This review aims to examine the full spectrum of tumor-EV studies and provide a comprehensive foundation to enhance the field. The topics which are discussed and scrutinized in this review encompass isolation techniques and how these issues need to be overcome for EV-based diagnostics, EVs and their roles in cancer biology, biomarkers for diagnosis and monitoring, EVs as vaccines, therapeutic targets, and EVs as drug delivery systems. We will also examine the challenges involved in EV research and promote a framework for catalyzing scientific discovery and innovation for tumor-EV-focused research.

Biomarkers for Gastric Cancer Screening and Early Diagnosis

Gastric cancer is one of the most common cancers worldwide, with a bad prognosis associated with late-stage diagnosis, significantly decreasing the overall survival. This highlights the importance of early detection to improve the clinical course of these patients. Although screening programs, based on endoscopic or radiologic approaches, have been useful in countries with high incidence, they are not cost-effective in low-incidence populations as a massive screening strategy. Additionally, current biomarkers used in daily routine are not specific and sensitive enough, and most of them are obtained invasively. Thus, it is imperative to discover new noninvasive biomarkers able to diagnose early-stage gastric cancer. In this context, liquid biopsy is a promising strategy. In this review, we briefly discuss some of the potential biomarkers for gastric cancer screening and diagnosis identified in blood, saliva, urine, stool, and gastric juice.

Urine miRNAs as potential biomarkers for systemic reactions induced by exposure to embedded metal

Aim: Explore the potential of urine microRNAs as biomarkers that may reflect the biological responses to pure metals embedded in skeletal muscle over time. Materials & methods: We tested a panel of military-relevant metals embedded in the gastrocnemius muscles of 3-month-old, male, Sprague-Dawley rats (n = 8/group) for a duration of 1, 3, 6 and 12 months, and performed small RNA-sequencing on the urine samples. Results: Results provide potential tissue targets affected by metal exposure and a list of unique or common urine microRNA biomarkers indicative of exposure to various metals, highlighting a complex systemic response. Conclusion: We have identified a panel of miRNAs as potential urine biomarkers to reflect the complex systemic response to embedded metal exposure.

Technical Challenges for CTC Implementation in Breast Cancer

Breast cancer is the most common neoplasm in women worldwide. Tissue biopsy, currently the gold standard to obtain tumor molecular information, is invasive and might be affected by tumor heterogeneity rendering it incapable to portray the complete dynamic picture by the absence of specific genetic changes during the evolution of the disease. In contrast, liquid biopsy can provide unique opportunities for real-time monitoring of disease progression, treatment response and for studying tumor heterogeneity combining the information of DNA that tumors spread in the blood (circulating tumor DNA) with CTCs analysis. In this review, we analyze the technical and biological challenges for isolation and characterization of circulating tumor cells from breast cancer patients. Circulating tumor cell (CTC) enumeration value is included in numerous clinical studies due to the prognostic's role of these cells. Despite this, there are so many questions pending to answer. How to manage lymphocytes background, how to distinguish the CTCs subtypes or how to work with frozen samples, are some of the issues that will discuss in this review. Based on our experience, we try to address these issues and other technical limitations that should be solved to optimize the standardization of protocols, sample extraction procedures, circulating-tumor material isolation (CTCs vs. ctDNA) and the very diverse methodologies employed, aiming to consolidate the use of CTCs in the clinic. Furthermore, we think that new approaches focusing on isolation CTCs in other body fluids such as cerebrospinal or ascitic fluid are necessary to increase the opportunities of circulating tumor cells in the practice clinic as well as to study the promising role of CTC clusters and their prognostic value in metastatic breast cancer.

Serum Exosomal Dicer Is a Useful Biomarker for Early Detection of Differentiated Gastric Adenocarcinoma

BACKGROUND AND AIM

A recent basic study identified that Dicer is contained in exosomes derived from cancer cells and plays crucial roles in microRNA maturation and cancer development. Based on this novel basic concept, we analyzed the usefulness of serum exosomal Dicer as a diagnostic biomarker for gastrointestinal cancers.

METHODS

Enrolled participants (691) were categorized into 3 groups: gastric cancer (GC) cohort, 183 patients (90 healthy controls (HCs) and 93 GC patients); esophageal cancer (EC) cohort, 115 patients (90 HCs and 25 EC patients); and colorectal cancer (CRC) cohort, 188 patients (92 HCs and 96 CRC patients) after age- and sex matching using the propensity score. The quality of isolated serum exosomes was validated with an electron microscope, particle size analyzer, and exosome marker, CD63.

RESULTS

Serum exosomal Dicer was significantly higher in the GC group than in the HC group (p = 0.004), whereas no significant differences were found in both EC and CRC cohorts. Serum exosomal Dicer was significantly higher in only differentiated gastric adenocarcinoma and not in the undifferentiated type. Moreover, serum exosomal Dicer showed no significant differences regardless of Helicobacter pylori (H. pylori) status. The biomarker panel combining serum exosomal Dicer with H. pylori status distinguished between HC and differentiated GC patients with an area under the curve (AUC) of 0.762. As for early-stage diagnosis, this combination distinguished between HC and stage I differentiated GC with an AUC = 0.758.

CONCLUSIONS

Serum exosomal Dicer is a potential noninvasive diagnostic biomarker for early detection of differentiated gastric adenocarcinoma.

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.

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.

Function of Non-coding RNA in Helicobacter pylori-Infected Gastric Cancer

Gastric cancer is a common malignant tumor of the digestive system. Its occurrence and development are the result of a combination of genetic, environmental, and microbial factors. Helicobacter pylori infection is a chronic infection that is closely related to the occurrence of gastric tumorigenesis. Non-coding RNA has been demonstrated to play a very important role in the organism, exerting a prominent role in the carcinogenesis, proliferation, apoptosis, invasion, metastasis, and chemoresistance of tumor progression. H. pylori infection affects the expression of non-coding RNA at multiple levels such as genetic polymorphisms and signaling pathways, thereby promoting or inhibiting tumor progression or chemoresistance. This paper mainly introduces the relationship between H. pylori-infected gastric cancer and non-coding RNA, providing a new perspective for gastric cancer treatment.

Urinary microRNA biomarkers for detecting the presence of esophageal cancer

Esophageal cancer (EC) including esophageal squamous cell carcinoma (ESCC) and adenocarcinoma (EAC) generally exhibits poor prognosis; hence, a noninvasive biomarker enabling early detection is necessary. Age- and sex-matched 150 healthy controls (HCs) and 43 patients with ESCC were randomly divided into two groups: 9 individuals in the discovery cohort for microarray analysis and 184 individuals in the training/test cohort with cross-validation for qRT-PCR analysis. Using 152 urine samples (144 HCs and 8 EACs), we validated the urinary miRNA biomarkers for EAC diagnosis. Among eight miRNAs selected in the discovery cohort, urinary levels of five miRNAs (miR-1273f, miR-619-5p, miR-150-3p, miR-4327, and miR-3135b) were significantly higher in the ESCC group than in the HC group, in the training/test cohort. Consistently, these five urinary miRNAs were significantly different between HC and ESCC in both training and test sets. Especially, urinary miR-1273f and miR-619-5p showed excellent values of area under the curve (AUC) ≥ 0.80 for diagnosing stage I ESCC. Similarly, the EAC group had significantly higher urinary levels of these five miRNAs than the HC group, with AUC values of approximately 0.80. The present study established novel urinary miRNA biomarkers that can early detect ESCC and EAC.

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.

Gastric cancer: a comprehensive review of current and future treatment strategies

Gastric cancer remains a major unmet clinical problem with over 1 million new cases worldwide. It is the fourth most commonly occurring cancer in men and the seventh most commonly occurring cancer in women. A major fraction of gastric cancer has been linked to variety of pathogenic infections including but not limited to Helicobacter pylori (H. pylori) or Epstein Barr virus (EBV). Strategies are being pursued to prevent gastric cancer development such as H. pylori eradication, which has helped to prevent significant proportion of gastric cancer. Today, treatments have helped to manage this disease and the 5-year survival for stage IA and IB tumors treated with surgery are between 60 and 80%. However, patients with stage III tumors undergoing surgery have a dismal 5-year survival rate between 18 and 50% depending on the dataset. These figures indicate the need for more effective molecularly driven treatment strategies. This review discusses the molecular profile of gastric tumors, the success, and challenges with available therapeutic targets along with newer biomarkers and emerging targets.

Multifunctional role of microRNAs in mesenchymal stem cell-derived exosomes in treatment of diseases

Mesenchymal stem cells can be replaced by exosomes for the treatment of inflammatory diseases, injury repair, degenerative diseases, and tumors. Exosomes are small vesicles rich in a variety of nucleic acids [including messenger RNA, Long non-coding RNA, microRNA (miRNA), and circular RNA], proteins, and lipids. Exosomes can be secreted by most cells in the human body and are known to play a key role in the communication of information and material transport between cells. Like exosomes, miRNAs were neglected before their role in various activities of organisms was discovered. Several studies have confirmed that miRNAs play a vital role within exosomes. This review focuses on the specific role of miRNAs in MSC-derived exosomes (MSC-exosomes) and the methods commonly used by researchers to study miRNAs in exosomes. Taken together, miRNAs from MSC-exosomes display immense potential and practical value, both in basic medicine and future clinical applications, in treating several diseases.

Novel urinary protein biomarker panel for early diagnosis of gastric cancer

Background

With the goal of discovering non-invasive biomarkers for early diagnosis of GC, we conducted a case-control study utilising urine samples from individuals with predominantly early GC vs. healthy control (HC).

Methods

Among urine samples from 372 patients, age- and sex-matched 282 patients were randomly divided into three groups: 18 patients in a discovery cohort; 176 patients in a training cohort and 88 patients in a validation cohort.

Results

Among urinary proteins identified in the comprehensive quantitative proteomics analysis, urinary levels of TFF1 (uTFF1) and ADAM12 (uADAM12) were significantly independent diagnostic biomarkers for GC, in addition to Helicobacter pylori status. A urinary biomarker panel combining uTFF1, uADAM12 and H. pylori significantly distinguished between HC and GC patients in both training and validation cohorts. On the analysis for sex-specific biomarkers, this combination panel demonstrated a good AUC of 0.858 for male GC, whereas another combination panel of uTFF1, uBARD1 and H. pylori also provided a good AUC of 0.893 for female GC. Notably, each panel could distinguish even stage I GC patients from HC patients (AUC = 0.850 for males; AUC = 0.845 for females).

Conclusions

Novel urinary protein biomarker panels represent promising non-invasive biomarkers for GC, including early-stage disease.

The potential of liquid biopsies in gastrointestinal cancer

BACKGROUND

Liquid biopsy is a novel approach for cancer diagnosis, the value of which in human gastrointestinal (GI) cancer has been confirmed by the previous studies. This article summarized the recent advances in liquid biopsy with a focus on novel technologies and the use of it in the screening, monitoring, and treatment of human GI cancer.

CONTENT

The concept of liquid biopsy was first used to define the detection of circulating tumor cells (CTCs) in cancer patients, and has been expanded to other biomarkers in blood and body fluids, such as circulating tumor DNA (ctDNA), extracellular vesicles (EVs) and circulating tumor RNA. If analyzed with proper and advanced techniques like next generation sequencing (NGS) or proteomics, liquid biopsies can open an enormous array of potential biomarkers. The amount changes of target biomarkers and the mutation of genetic materials provide quantitative and qualitative information, which can be utilized clinically for cancer diagnosis and disease monitoring.

SUMMARY

As a highly efficient, minimally invasive, and cost-effective approach to diagnose and evaluate prognosis of GI cancer, liquid biopsy has lots of advantages over traditional biopsy and is promising in future clinical utility. If the challenges are overcome in the near future, liquid biopsy will become a widely available and dependable option.

Omental adipocytes promote peritoneal metastasis of gastric cancer through the CXCL2-VEGFA axis

Background

Gastric cancer (GC) patients frequently develop peritoneal metastasis; however, the underlying mechanism remains unknown. We hypothesised that omental adipocytes (OmAd) trigger GC cells towards malignant activity to induce peritoneal metastasis.

Methods

We analysed interactions among human GC cells, endothelial cells and OmAd using a 3D co-culture system. We also employed a multipronged animal study, including subcutaneous and orthotopic tumours, and humanised omental adipose tissue models. Urinary levels of CXCL2 were analysed in human GC patients with and without peritoneal metastasis.

Results

Conditioned media derived from OmAd (OmAd-CM) promoted the proliferation, migration and capacity to induce angiogenesis of GC cells through AKT phosphorylation and VEGFA overexpression, whereas silencing CXCL2 in OmAd cancelled OmAd-induced effects. In an orthotopic tumour model using SCID mice, omentectomy suppressed GC growth and peritoneal dissemination, and reduced serum levels of CXCL2. OmAd promoted GC growth in a humanised omental adipose tissue model using NSG mice, but silencing CXCL2 in OmAd cancelled OmAd-induced tumour growth. Finally, urinary levels of CXCL2 were significantly higher in GC patients with peritoneal metastasis than in those without.

Conclusion

Omental adipocytes trigger GC cells to an aggressive phenotype through CXCL2 secretion, which induces angiogenesis followed by cell growth and peritoneal metastasis.

MicroRNA-4290 suppresses PDK1-mediated glycolysis to enhance the sensitivity of gastric cancer cell to cisplatin

The development of chemotherapy resistance significantly impairs the efficiency of chemotherapy, but the underlying mechanisms of chemotherapy resistance in gastric cancer (GC) are complicated and still need to be further explored. Here, we aimed to reveal the effects of miR-4290/PDK1 (pyruvate dehydrogenase kinase 1) axis on chemotherapy resistance of GC in vitro. The expression patterns of miR-4290 in GC tissues and cell lines were determined by real-time quantitative PCR. Kaplan-Meier was used to assess the relationship between miR-4290 expression levels and patients' overall survival. CCK-8 and flow cytometry technologies were applied to detect cell proliferation and apoptosis. The luciferase gene reporter assay was used to evaluate the interaction between miR-4290 and PDK1. miR-4290 was lowly expressed in GC tissues and cell lines, which was closely associated with the shorter overall survival of GC patients. miR-4290 mimics significantly inhibited cell proliferation and induced cell apoptosis, as well as induced a significant reduction in the expression of PDK1. Moreover, miR-4290 significantly inhibited glycolysis and decreased the IC50 value to cisplatin in SGC7901 cells, whereas these effects were abolished and cell apoptosis was promoted when PDK1 was overexpressed. In conclusion, this study revealed that miR-4290 suppressed PDK1-mediated glycolysis to enhance the sensitivity of GC cells to cisplatin.

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.

The power of microRNAs as diagnostic and prognostic biomarkers in liquid biopsies

In the last decades, progresses in medical oncology have ameliorated the treatment of patients and their outcome. However, further improvements are still necessary, in particular for certain types of tumors such as pancreatic, gastric, and lung cancer as well as acute myeloid leukemia where early detection and monitoring of the disease are crucial for final patient outcome. Liquid biopsy represents a great advance in the field because it is less invasive, less time-consuming, and safer compared to classical biopsies and it can be useful to monitor the evolution of the disease as well as the response of patients to therapy. Liquid biopsy allows the detection of circulating tumor cells, nucleic acids, and exosomes not only in blood but also in different biological fluids: urine, saliva, pleural effusions, cerebrospinal fluid, and stool. Among the potential biomarkers detectable in liquid biopsies, microRNAs (miRNAs) are gaining more and more attention, since they are easily detectable, quite stable in biological fluids, and show high sensitivity. Many data demonstrate that miRNAs alone or in combination with other biomarkers could improve the diagnostic and prognostic power for many different tumors. Despite this, standardization of methods, sample preparation, and analysis remain challenging and a huge effort should be made to address these issues before miRNA biomarkers can enter the clinic. This review summarizes the main findings in the field of circulating miRNAs in both solid and hematological tumors.

MiR-122-5p suppresses the proliferation, migration, and invasion of gastric cancer cells by targeting LYN

Gastric cancer (GC) is one of malignant tumors with high mortality and morbidity in the world. MicroRNA-122 (miR-122) acts as a tumor suppressor in a variety of cancers and has been found to be dominant in gastric adenocarcinoma. However, the specific biological function of miR-122-5p in GC is not completely clear. In this study, we found that miR-122-5p was low-expressed in GC tissues and cell lines by using qRT-PCR. Overexpression of miR-122-5p inhibited the proliferation, migration, and invasion of GC cells by using CCK-8 and transwell assays. On the contrary, downregulation of miR-122-5p promoted the proliferation, migration, and invasion of GC cells. In addition, we found that the expression of LYN, an Src family tyrosine kinase, was inversely correlated with miR-122-5p expression in GC tissues by using western blot analysis, immunohistochemistry, and qRT-PCR assays. Meanwhile, luciferase assay results indicated that LYN is a direct target of miR-122-5p in GC cells. Moreover, silencing LYN expression by its siRNA inhibited the proliferation, migration, and invasion of GC cells. Importantly, overexpression of LYN restored miR-122-5p-mediated inhibition of the proliferation, migration, and invasion of GC cells. Taken together, our results indicated miR-122-5p inhibited the proliferation, migration, and invasion by targeting LYN in GC.

Use of a Four-miRNA Panel as a Biomarker for the Diagnosis of Stomach Adenocarcinoma

BACKGROUND

MicroRNAs (miRNAs) have been applied to cancer diagnosis taking into account their role in tumorigenesis. The main purpose of our study was to confirm the possibility of using miRNAs as noninvasive biomarkers for stomach adenocarcinoma (STAD) diagnosis.

METHODS

A total of 246 participants (130 STAD patients and 116 healthy controls (HCs)) were enrolled in this 3-phase study. Five STAD pools and 3 HC pools (with 4 participants in each pool) were used for the screening of the 28 miRNAs using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The training phase (30 STAD patients vs. 24 HCs) and validation phase (80 STAD patients vs. 80 HCs) were used to further verify the identity of these miRNAs. Kaplan-Meier survival analysis and bioinformatics analysis were also used.

RESULTS

The expression levels of miR-125b-5p and miR-196a-5p were upregulated in STAD serum, compared with the HCs, while miR-1-3p and miR-149-5p showed the opposite result. A four-serum miRNA panel was constructed, and the area under the receiver operating characteristic curve (AUC) was found to be 0.892 (95% CI: 0.834 to 0.936, sensitivity = 86.25%, specificity = 78.75%). Only miR-125b-5p expression showed a significant difference between STAD patients and NCs in the survival analysis. The neurotrophin signaling pathway was associated with 4 miRNAs identified in STAD patients.

CONCLUSION

The four-serum miRNA panel has great potential to be used as a noninvasive biomarker for STAD diagnosis.

Current status of urinary diagnostic biomarkers for colorectal cancer

Fecal occult blood test (FOBT) and flexible sigmoidoscopy are the currently using screening methods for colorectal cancer (CRC). However, these methods still have problems of high false positive rates in FOBT and increased invasiveness and cost associated with endoscopy. The development of non-invasive biomarkers is thus important for the diagnosis of CRC. Urine is one of the most commonly used samples for mass screening owing to its non-invasive and simple process of collection; however, the discovery of urinary diagnostic biomarkers for malignancies is still challenging and developing. Since urine contains abundant substances reflecting systemic body condition, urinary biomarker might contribute to detect CRC in a completely non-invasive manner. In this review, we describe the current utility of urinary diagnostic biomarkers for CRC.