Urinary miRNAs as a Diagnostic Tool for Bladder Cancer: A Systematic Review

Validation of a microRNA profile in urine liquid biopsy with diagnostic and stratification value for bladder cancer classification, available through the open app BladdermiRaCan

We aimed to identify a profile of urine microRNAs (miRNAs) with diagnostic and stratification potential in the whole range of bladder cancer (BC) categories, to avoid current invasive, harmful and expensive procedures. We collected a first morning urine sample from the screening (35 BC patients and 15 age- and gender-matched controls) and validation cohorts (172 BC and 94 controls). In the screening stage we analyzed the expression level of 179 miRNAs by real-time reverse transcription quantitative PCR in urine supernatants. miRNA levels in each sample were normalized by the levels of the previously identified and stably expressed miR-29c-3p. We performed an ordinal regression for each miRNA with False Discovery Rate (FDR) adjustment to identify dysregulated miRNAs, and an ordinal elastic net logistic regression model to identify a miRNA profile for BC diagnosis and stratification with the software R (v3.5.1). Next, we validated the most dysregulated miRNAs, and empirically identified the real miRNA targets in BC cells by miR-eCLIP immunoprecipitation and sequencing. We identified 70 dysregulated miRNAs in BC patients (p < 0.05 FDR-adjusted). With the expression level of 7 miRNAs in urine (miR-221-3p, miR-93-5p, miR-362-3p, miR-191-5p, miR-200c-3p, miR-192-5p, miR-21-5p) we could stratify BC patients and control subjects. To enable the global use of our model, we developed the free BladdermiRaCan online tool. Furthermore, we identified miR-21-5p, miR-425-5p and miR-99a-5p as follow-up markers for BC relapse, and miR-21-5p and miR-221-3p as markers for metastasis. These miRNAs were also dysregulated in BC tissue sections from a subgroup of patients from which urine samples were studied. In conclusion, we have validated and patented a 7-miRNAs urine profile able to diagnose and stratify BC patients; BladdermiRaCan will enable the global use of our model. The experimentally verified target proteins identified for these miRNAs may unravel novel therapeutic targets.

Liquid Biopsy Based Bladder Cancer Diagnostic by Machine Learning

Background/Objectives: The timely diagnostics of bladder cancer is still a challenge in clinical settings. The reliability of conventional testing methods does not reach desirable accuracy and sensitivity, and it has an invasive nature. The present study examines the application of machine learning to improve bladder cancer diagnostics by integrating miRNA expression levels, demographic routine laboratory test results, and clinical data. We proposed that merging these datasets would enhance diagnostic accuracy. Methods: This study combined molecular biology methods for liquid biopsy, routine clinical data, and application of machine learning approach for the acquired data analysis. We evaluated urinary exosome miRNA expression data in combination with patient test results, as well as clinical and demographic data using three machine learning models: Random Forest, SVM, and XGBoost classifiers. Results: Based solely on miRNA data, the SVM model achieved an ROC curve area of 0.75. Patient analysis' clinical and demographic data obtained ROC curve area of 0.80. Combining both data types enhanced performance, resulting in an F1 score of 0.79 and an ROC of 0.85. The feature importance analysis identified key predictors, including erythrocytes in urine, age, and several miRNAs. Conclusions: Our findings indicate the potential of a multi-modal approach to improve the accuracy of bladder cancer diagnosis in a non-invasive manner.

Review of microRNA detection workflows from liquid biopsy for disease diagnostics

MicroRNAs have emerged as effective biomarkers in disease diagnostics, particularly cancer, due to their role as regulatory sequences. More recently, microRNAs have been detected in liquid biopsies, which hold immense potential for early disease diagnostics. This review comprehensively analyses distinct liquid biopsy microRNA detection methods validated with clinical samples. Each step in the microRNA detection workflow, including sample collection, RNA isolation, processing, and detection of target microRNAs, has been thoroughly assessed. The review discusses the advantages and limitations of established and novel techniques in microRNA detection workflows, discussing their diagnostic capabilities and potential for future implementation at scale.

Urinary miRNA Expression in Pre-Eclampsia During Early and Mid-Pregnancy

Background: Pre-eclampsia (PE) is a serious condition affecting 2-8% of pregnancies worldwide, leading to high maternal and fetal morbidity and mortality. MicroRNAs (miRNAs), small non-coding RNA molecules, have emerged as potential biomarkers for various pregnancy-related pathologies, including PE. MiRNAs in plasma and serum have been extensively studied, but urinary miRNAs remain underexplored, especially during early pregnancy. This study aimed to investigate the urinary miRNA expression profiles in women with pre-eclampsia during the first and second trimesters. Materials and Methods: A prospective study was conducted using 48 urine samples from 24 pregnant women (n = 12 pre-eclampsia and n = 12 controls). Urine samples were collected in the first (9-13 weeks) and second (22-24 weeks) trimesters. MiRNA isolation, library preparation, and high-throughput sequencing were performed, followed by differential expression and enrichment analyses. Results: In the first trimester, five miRNAs were dysregulated in PE in comparison with the control group (hsa-miR-184, hsa-miR-203a-3p, hsa-miR-205-5p, hsa-miR-223-3p-downregulated; hsa-miR-1-3p-upregulated). In the second trimester, hsa-miR-205-5p and hsa-miR-223-3p were downregulated, and hsa-miR-9-5p, hsa-miR-1-3p, and hsa-miR-206 were upregulated. Conclusions: Our study identified differentially expressed miRNAs in the urine of pre-eclamptic patients during early pregnancy. These findings suggest that specific urinary miRNAs could serve as non-invasive biomarkers for the early detection and risk assessment of pre-eclampsia. The changes in the level of differential expression of miRNAs during gestation highlight their role in the progression of PE. Further research and validation with a larger cohort are needed to explore their clinical potential for improving maternal and fetal outcomes through early intervention.

Epigenetic Biomarkers as a New Diagnostic Tool in Bladder Cancer-From Early Detection to Prognosis

Bladder cancer (BC) currently ranks as the 9th most common cancer worldwide. It is characterised by very high rates of recurrence and metastasis. Most cases of BC are of urothelial origin, and due to its ability to penetrate muscle tissue, BC is divided into non-muscle-invasive BC (NMIBC) and muscle-invasive BC (MIBC). The current diagnosis of BC is still based primarily on invasive cystoscopy, which is an expensive and invasive method that carries a risk of various complications. Urine sediment cytology is often used as a complementary test, the biggest drawback of which is its very low sensitivity concerning the detection of BC at early stages, which is crucial for prompt implementation of appropriate treatment. Therefore, there is a great need to develop innovative diagnostic techniques that would enable early detection and accurate prognosis of BC. Great potential in this regard is shown by epigenetic changes, which are often possible to observe long before the onset of clinical symptoms of the disease. In addition, these changes can be detected in readily available biological material, such as urine or blood, indicating the possibility of constructing non-invasive diagnostic tests. Over the past few years, many studies have emerged using epigenetic alterations as novel diagnostic and prognostic biomarkers of BC. This review provides an update on promising diagnostic biomarkers for the detection and prognosis of BC based on epigenetic changes such as DNA methylation and expression levels of selected non-coding RNAs (ncRNAs), taking into account the latest literature data.

Relapse and Survival in Bladder Cancer Patients Undergoing microRNA-129 and microRNA-145 Assays

OBJECTIVE

The lack of indicators to measure tumor's invasive biological behavior is an important issue. The aim of this study was to examine the effect of miRNAs 129 and 145 on tumor progression as well as patient survival.

METHOD

Seventy five breast cancer (BC) patients and 75 controls were included in this research. Two miRNA expressions were estimated using real-time PCR. Biomarkers for BC detection was tested using ROC curves and AUC.

RESULT

miR-129 and miR-145 expressions were significant. miR-129 and miR-145 classifiers (AUC = 0.943 and 0.748, respectively) help diagnose BC. Unlike miR-145, miR-129 did not affect the Kaplan-Meier survival curve analysis for progression-free survival at the end of the trial. The development of transitional cell carcinoma disease was found to have a strong correlation with miR-145 in both univariate and multivariate Cox regression analyses. Additionally, infiltrating + invasive urothelial carcinoma was also found to be correlated with miR-145. Conversely, elevated miR-129 expression in BC patients did not lead to an increase in cancer-specific recurrence or mortality, as observed in both univariate and multivariate Cox regression studies.

CONCLUSION

The miRNA signature can help detect survival-associated miRNAs and develop BC miRNA therapeutics.

Potential clinical application of microRNAs in bladder cancer

Bladder cancer (BC) is the tenth most prevalent malignancy globally, presenting significant clinical and societal challenges because of its high incidence, rapid progression, and frequent recurrence. Presently, cystoscopy and urine cytology serve as the established diagnostic methods for BC. However, their efficacy is limited by their invasive nature and low sensitivity. Therefore, the development of highly specific biomarkers and effective non-invasive detection strategies is imperative for achieving a precise and timely diagnosis of BC, as well as for facilitating an optimal tumor treatment and an improved prognosis. microRNAs (miRNAs), short noncoding RNA molecules spanning around 20-25 nucleotides, are implicated in the regulation of diverse carcinogenic pathways. Substantially altered miRNAs form robust functional regulatory networks that exert a notable influence on the tumorigenesis and progression of BC. Investigations into aberrant miRNAs derived from blood, urine, or extracellular vesicles indicate their potential roles as diagnostic biomarkers and prognostic indicators in BC, enabling miRNAs to monitor the progression and predict the recurrence of the disease. Simultaneously, the investigation centered on miRNA as a potential therapeutic agent presents a novel approach for the treatment of BC. This review comprehensively analyzes biological roles of miRNAs in tumorigenesis and progression, and systematically summarizes their potential as diagnostic and prognostic biomarkers, as well as therapeutic targets for BC. Additionally, we evaluate the progress made in laboratory techniques within this field and discuss the prospects.

Amplification-Free Analysis of Bladder Cancer MicroRNAs on Wrinkled Silica Nanoparticles with DNA-Functionalized Quantum Dots

Bladder cancer (BC) occurrence and progression are accompanied by alterations in microRNAs (miRNAs) expression levels. Simultaneous detection of multiple miRNAs contributes to the accuracy and reliability of the BC diagnosis. In this work, wrinkled silica nanoparticles (WSNs) were applied as the microreactor for multiplex miRNAs analysis without enzymes or nucleic acid amplification. Conjugated on the surface of WSNs, the S9.6 antibody was adopted as the universal module for binding DNA/miRNA duplexes, regardless of their sequence. Furthermore, single-stranded DNA (ssDNA) was labeled with quantum dots (QDs) for identifying a given miRNA to form QDs-ssDNA/miRNA, which enabled the specific capture of the corresponding QDs on the wrinkled surface of WSNs. Based on the detection of fluorescence signals that were ultimately focused on WSNs, target miRNAs could be sensitively identified to a femtomolar level (5 fM) with a wide dynamic range of up to 6 orders of magnitude. The proposed strategy achieved high specificity to obviously distinguish single-base mutation sequences and possessed multiplex assay capability. Moreover, the assay exhibited excellent practicability in the multiplex detection of miRNAs in clinical serum specimens.

Urinary markers for bladder cancer diagnosis: A review of current status and future challenges

Bladder cancer is a common urological cancer with a high recurrence rate that requires long-term follow-up, and early detection positively affects prognosis. To date, the initial diagnosis and follow-up for bladder cancer rely on cystoscopy, which is an invasive and expensive procedure. Therefore, urinary markers for the detection of bladder cancer have attracted research attention for decades to reduce unnecessary cystoscopies. Urine, which is in continuous contact with bladder cancer, is considered a suitable fluid for providing tumor information. Urinary cytology is the only widely used urinary marker in clinical practice; however, it has poor sensitivity for low-grade tumors; indicating the need for novel urinary markers. Considerable research has been conducted on this topic over the years, resulting in a complex landscape with a wide range of urinary markers, including protein-, exfoliated cell-, RNA-, DNA-, and extracellular vesicle-based markers. Although some of these markers have been approved by the U.S. Food and Drug Administration and are commercially available, their use in clinical practice is limited. To facilitate clinical application, potential urinary markers must withstand prospective clinical trials and be easy for patients and clinicians to understand and utilize in a clinical context. This review provides a comprehensive overview of currently available and recently reported promising urinary markers for bladder cancer. Additionally, the challenges and the prospects of these urinary markers for clinical implementation in bladder cancer treatment were discussed.

Urinary miRNAs: Technical Updates

Due to its non-invasive nature and easy accessibility, urine serves as a convenient biological fluid for research purposes. Furthermore, urine samples are uncomplicated to preserve and relatively inexpensive. MicroRNAs (miRNAs), small molecules that regulate gene expression post-transcriptionally, play vital roles in numerous cellular processes, including apoptosis, cell differentiation, development, and proliferation. Their dysregulated expression in urine has been proposed as a potential biomarker for various human diseases, including bladder cancer. To draw reliable conclusions about the roles of urinary miRNAs in human diseases, it is essential to have dependable and reproducible methods for miRNA extraction and profiling. In this review, we address the technical challenges associated with studying urinary miRNAs and provide an update on the current technologies used for urinary miRNA isolation, quality control assessment, and miRNA profiling, highlighting both their advantages and limitations.

MicroRNAs for detecting occult genitourinary cancer

PURPOSE OF REVIEW

Genitourinary (GU) malignancies are a real burden in global health worldwide. Each model has its own clinical challenges, and the early screening and/or detection of occult cancer in follow-up is transversal to all of them. MicroRNAs (miRNAs) have been proposed as minimally invasive liquid biopsy cancer biomarkers, due to their stability and low degradation.

RECENT FINDINGS

The different GU tumor models are in different stages concerning miRNAs as biomarkers for cancer detection. Testicular germ cell tumors (TGCTs) already have a specific defined target, miR-371a-3p, that has shown high sensitivity and specificity in different clinical settings, and is now in final stages of preanalytical testing before entering the clinic. The other GU malignancies are in a different stage, with many liquid biopsy studies (both in urine and plasma/serum) being currently performed, but there is not an agreeable miRNA or set of miRNAs that is ready to follow the footsteps of miR-371a-3p in TGCTs.

SUMMARY

Further studies with proper molecular characterization of miRNA profiles of GU malignancies and standardization of sampling, biobanking and formal analysis may aid in the advance and choosing of specific target sets to be used for occult cancer detection.

Characterization of a miRNA Signature with Enhanced Diagnostic and Prognostic Power for Patients with Bladder Carcinoma

Bladder carcinoma is globally among the most prevalent cancers and is associated with a high mortality rate at advanced stages. Its detection relies on invasive diagnostic methods that are unpleasant for the patient. Non-invasive molecular biomarkers, such as miRNAs, could serve as alternatives for early detection and prognosis of this malignancy. We designed a computational approach that combines transcriptome profiling, survival analyses, and calculation of diagnostic power in order to isolate miRNA signatures with high diagnostic and prognostic utility. Our analysis of TCGA-BLCA data from 429 patients yielded one miRNA signature, consisting of five upregulated and three downregulated miRNAs with cumulative diagnostic power that outperforms current diagnostic methods. The same miRNAs have a strong prognostic significance since their expression is associated with the overall survival of bladder cancer patients. We evaluated the expression of this signature in 19 solid cancer types, supporting its unique diagnostic utility for bladder carcinoma. We provide computational evidence regarding the functional implications of this miRNA signature in cell cycle regulation, demonstrating its abundance in body fluids, including peripheral blood and urine. Our study characterized a novel miRNA signature with the potential to serve as a non-invasive method for bladder cancer diagnosis and prognosis.

An Overview of Angiogenesis in Bladder Cancer

PURPOSE OF THE REVIEW

Angiogenesis plays a key role in bladder cancer (BC) pathogenesis. In the last two decades, an increasing number of publications depicting a multitude of novel angiogenic molecules and pathways have emerged. The growing complexity necessitates an evaluation of the breadth of current knowledge to highlight key findings and guide future research.

RECENT FINDINGS

Angiogenesis is a dynamic biologic process that is inherently difficult to assess. Clinical assessment of angiogenesis in BCs is advancing with the integration of image analysis systems and dynamic contrast-enhanced and magnetic resonance imaging (DCE-MRI). Tumour-associated macrophages (TAMs) significantly influence the angiogenic process, and further research is needed to assess their potential as therapeutic targets. A rapidly growing list of non-coding RNAs affect angiogenesis in BCs, partly through modulation of vascular endothelial growth factor (VEGF) activity. Vascular mimicry (VM) has been repeatedly associated with increased tumour aggressiveness in BCs. Standardised assays are needed for appropriate identification and quantification of VM channels. This article demonstrates the dynamic and complex nature of the angiogenic process and asserts the need for further studies to deepen our understanding.

Targeted and untargeted urinary metabolic profiling of bladder cancer

Bladder cancer (BC) is frequent cancer affecting the urinary tract and is one of the most prevalent malignancies worldwide. No biomarkers that can be used for effective monitoring of therapeutic interventions for this cancer have been identified to date. This study investigated polar metabolite profiles in urine samples from 100 BC patients and 100 normal controls (NCs) using nuclear magnetic resonance (NMR) and two methods of high-resolution nanoparticle-based laser desorption/ionization mass spectrometry (LDI-MS). Five urine metabolites were identified and quantified using NMR spectroscopy to be potential indicators of bladder cancer. Twenty-five LDI-MS-detected compounds, predominantly peptides and lipids, distinguished urine samples from BC and NCs individuals. Level changes of three characteristic urine metabolites enabled BC tumor grades to be distinguished, and ten metabolites were reported to correlate with tumor stages. Receiver-Operating Characteristics analysis showed high predictive power for all three types of metabolomics data, with the area under the curve (AUC) values greater than 0.87. These findings suggest that metabolite markers identified in this study may be useful for the non-invasive detection and monitoring of bladder cancer stages and grades.

Urine Biomarkers in the Management of Adult Neurogenic Lower Urinary Tract Dysfunction: A Systematic Review

BACKGROUND

Neurogenic lower urinary tract dysfunction requires lifelong surveillance and management for the perseveration of patients' quality of life and the prevention of significant morbidity and mortality. Urine biomarkers are an attractive noninvasive method of surveillance for these patients. The aim of this systematic review is to search for and critically appraise studies that investigate the clinical usefulness of urine biomarkers in the management of neurogenic lower urinary tract dysfunction (NLUTD) in adults.

METHODS

This review was conducted according to PRISMA and MOOSE guidelines. Search strategy included PubMed, CENTRAL, and Scopus (until October 2022). Studies investigating potential urine biomarkers for the management of adults with NLUTD were included.

RESULTS

Fifteen studies fulfilled the criteria. To date, a variety of different urine molecules have been investigated for the diagnosis and management of neurogenic overactive bladder and detrusor overactivity (nerve growth factor, brain-derived neurotrophic factor, prostaglandin E2, prostaglandin F2α, transformation growth factor β-1, tissue inhibitor metalloproteinase-2, matrix metalloproteinase-2, substance P, microRNA), diagnosis of vesicoureteral reflux (exosomal vitronectin), urinary tract infection (neutrophil gelatinase-associated lipocalin, interleukin 6) and bladder cancer screening (cytology, BTA stat, survivin) in neurological patients.

CONCLUSION

Further studies are needed to specify the utility of each molecule in the management algorithm of adult NLUTD.