Urine exosomes as biomarkers in bladder cancer diagnosis and prognosis: From functional roles to clinical significance

New perspectives of exosomes in urologic malignancies - Mainly focus on biomarkers and tumor microenvironment

Bladder cancer (BCa) and renal cell carcinoma (RCC) are prevalent urologic malignancies (UM) characterized by high morbidity and frequent recurrence. Current diagnostic approaches, often invasive, often indicate an advanced disease stage. And the complex tumor microenvironment often promotes tumor progression and induces resistance to chemotherapy. Current diagnostic and therapeutic modalities often fail to achieve satisfactory outcomes for patients. Exosomes transport diverse cargoes, including cytokines, proteins, lipids, non-coding RNAs, and microRNAs, crucial for intercellular communication. Exosomes have shown potential as biomarkers for UM, participating in tumor progression, especially within the tumor microenvironment (TME), including tumor cell apoptosis, proliferation, migration, invasion, depletion of immune cell function, epithelial-mesenchymal transition (EMT), angiogenesis, and more.In this review, we summarize research advances related to exosomes in UM, focusing on the role of exosomes as biomarkers in bladder and renal cancer, highlighting their significance within the TME.

Long-Term Changes of Urinary Exosomal Peptide Levels After Thyroidectomy in Patients with Thyroid Cancer: A Prospective Observational Study

Background

The recurrence rate of thyroid cancer can be as high as 30%. The purpose of this study was to examine changes of urine exosomal peptide levels after thyroidectomy in patients with thyroid cancer to determine if levels can predict the risk of recurrence.

Methods

Patients >20 years old as newly diagnosed with papillary thyroid cancer who had received a thyroidectomy were recruited. Urine samples were collected at 12 months after enrollment to the study, and 1 year later. Urine exosomes containing different peptides were identified and compared.

Results

A total of 70 patients were enrolled in the study, and were classified by the interval between surgery and enrollment: 42 patients with < 5 years between surgery and enrollment, 14 patients between 5-10 years, and 14 patients longer than 10 years. No recurrence was observed in any patient during the 2 years after enrollment. No significant differences were found in the levels of serum proteins or urine exosomal peptides between groups, or between intervals. Known risk factors for high-risk thyroid cancer had only a mild correlation with serum protein levels and urine exosomal peptides.

Conclusion

Our study revealed the long-term basal fluctuation ranges of serum proteins and urine exosomal peptides in patients with thyroid cancer who underwent thyroidectomy. For high-risk patients after thyroidectomy, concentrations of serum proteins or urine exosomal peptides within the ranges may indicate there is a lower risk of thyroid cancer recurrence during long-term follow-up.

Trial Registration

ClinicalTrials.gov: NCT03488134.

Bladder Cancer in Exosomal Perspective: Unraveling New Regulatory Mechanisms

Bladder cancer, a prevalent malignant neoplasm of the urinary tract, exhibits escalating morbidity and mortality rates. Current diagnosis standards rely on invasive and costly cystoscopy and histopathology, underscoring the urgency for non-invasive, high-throughput, and cost-effective novel diagnostic techniques to ensure timely detection and standardized treatment. Recent years have witnessed the rise of exosome research in bladder cancer studies. Exosomes contain abundant bioactive molecules that can help elucidate the intricate mechanisms underlying bladder cancer pathogenesis and metastasis. Exosomes hold potential as biomarkers for early bladder cancer diagnosis while also serving as targeted drug delivery vehicles to enhance treatment efficacy and mitigate adverse effects. Furthermore, exosome analyses offer insights into the complex molecular signaling networks implicated in bladder cancer progression, revealing novel therapeutic targets. This review provides a comprehensive overview of prevalent exosome isolation techniques and highlights the promising clinical utility of exosomes in both diagnostic and therapeutic applications in bladder cancer management.

Beyond blood: Advancing the frontiers of liquid biopsy in oncology and personalized medicine

Liquid biopsy is emerging as a pivotal tool in precision oncology, offering a noninvasive and comprehensive approach to cancer diagnostics and management. By harnessing biofluids such as blood, urine, saliva, cerebrospinal fluid, and pleural effusions, this technique profiles key biomarkers including circulating tumor DNA, circulating tumor cells, microRNAs, and extracellular vesicles. This review discusses the extended scope of liquid biopsy, highlighting its indispensable role in enhancing patient outcomes through early detection, continuous monitoring, and tailored therapy. While the advantages are notable, we also address the challenges, emphasizing the necessity for precision, cost-effectiveness, and standardized methodologies in its broader application. The future trajectory of liquid biopsy is set to expand its reach in personalized medicine, fueled by technological advancements and collaborative research.

Urinary exosomal mRNA as a biomarker for the diagnosis of bladder cancer

OBJECTIVE

To study the diagnostic value of mRNA expression in urinary exocrine body in bladder cancer.

METHODS

From February 2022 to December 2022, 60 patients diagnosed with bladder cancer by pathology in the Department of Urology, Affiliated Hospital of Chengde Medical University were selected as the case group. In total, 40 healthy subjects receiving physical examinations were selected as the control group. 100 mL of morning urine samples were collected from the subjects in both groups based on the same standard. Three subjects were randomly selected from each group. Urinary exosomes were extracted by differential ultracentrifugation. High-throughput sequencing (RNA-seq) was used to detect mRNA expression profiles in urinary exosomes and identify differentially expressed genes. Bioinformatic analysis was performed to predict major biological functions of differentially expressed genes and related signaling pathways. RT-PCR validated expression levels of differentially expressed genes in urinary exosomes between the two groups. ROC curves evaluated the diagnostic value of differential genes for bladder cancer. Spearman's correlation analysis determined correlations between differentially expressed genes and the occurrence of bladder cancer. ROC curves speculated the diagnostic value of using combined differentially expressed genes.

RESULTS

Compared with normal subjects, there were 189 significantly differentially expressed genes in urinary exosomes of bladder cancer patients, including 33 up-regulated and 156 down-regulated. According to go and kyoto encyclopedia of genes and genomes (KEGG) analysis, the above differentially expressed genes may participate in the occurrence and development of bladder cancer through the MAPK pathway, PPAP signaling pathway, PI3K Akt signaling pathway and Hippo signaling pathway, affect protein and lipid metabolism, RNase activity, polysaccharide synthesis, signal transduction and other biological processes, and participate in cell proliferation, death, movement and adhesion, as well as cell differentiation and signal transduction. RT-PCR verified that the expression of tmeff1, SDPR, ACBD7, SCG2 and COL6A2 in the two groups of samples was statistically significant ( P  < 0.05). The ROC curve showed that the area under curve area under the curve of the five differential genes were 0.6934, 0.7746, 0.7239, 0.6396 and 0.6610, respectively. The sensitivity was 42.11%, 64.86%, 47.37%, 73.53% and 76.47%, and the specificity was 90%, 81.36%, 96.36%, 61.02% and 58.18%, respectively. Spearman correlation analysis showed that tmeff1, SDPR and acbd7 were associated with the occurrence of bladder cancer. The ROC curve of the combined diagnosis of the three and the two combined diagnoses suggested that the area under the curve of the combined diagnosis of SDPR and acbd7 was 0.7945, the sensitivity was 89.09%, and the specificity was 60.53%.

CONCLUSION

The gene expression profile in urinary exosomes of bladder cancer patients has changed significantly, and the differential genes may play an important biological role in the occurrence and development of bladder cancer. The combined detection of urinary exosome SDPR and ACBD7 has a certain diagnostic value for bladder cancer.

Potential molecular biomarkers for the diagnosis and prognosis of bladder cancer

Bladder cancer (BC) is a common malignant tumor of urinary system, which can be divided into muscle-invasive BC (MIBC) and nonmuscle-invasive BC (NMIBC). The number of BC patients has been gradually increasing currently. At present, bladder tumours are diagnosed and followed-up using a combination of cystoscopic examination, cytology and histology. However, the detection of early grade tumors, which is much easier to treat effectively than advanced stage disease, is still insufficient. It frequently recurs and can progress when not expeditiously diagnosed and monitored following initial therapy for NMIBC. Treatment strategies are totally different for different stage diseases. Therefore, it is of great practical significance to study new biomarkers for diagnosis and prognosis. In this review, we summarize the current state of biomarker development in BC diagnosis and prognosis prediction. We retrospectively analyse eight diagnostic biomarkers and eight prognostic biomarkers, in which CK, P53, PPARγ, PTEN and ncRNA are emphasized for discussion. Eight molecular subtype systems are also identified. Clinical translation of biomarkers for diagnosis, prognosis, monitoring and treatment will hopefully improve outcomes for patients. These potential biomarkers provide an opportunity to diagnose tumors earlier and with greater accuracy, and help identify those patients most at risk of disease recurrence.

Progress and challenges in intravesical drug delivery

INTRODUCTION

Intravesical drug delivery (IDD) has gained recognition as a viable approach for treating bladder-related diseases over the years. However, it comes with its set of challenges, including voiding difficulties and limitations in mucosal and epithelial penetration. These challenges lead to drug dilution and clearance, resulting in poor efficacy. Various strategies for drug delivery have been devised to overcome these issues, all aimed at optimizing drug delivery. Nevertheless, there has been minimal translation to clinical settings.

AREAS COVERED

This review provides a detailed description of IDD, including its history, advantages, and challenges. It also explores the physical barriers encountered in IDD, such as voiding, mucosal penetration, and epithelial penetration, and discusses current strategies for overcoming these challenges. Additionally, it offers a comprehensive roadmap for advancing IDD into clinical trials.

EXPERT OPINION

Physical bladder barriers and limitations of conventional treatments result in unsatisfactory efficacy against bladder diseases. Nevertheless, substantial recent efforts in this field have led to significant progress in overcoming these challenges and have raised important attributes for an optimal IDD system. However, there is still a lack of well-defined steps in the workflow to optimize the IDD system for clinical settings, and further research is required to establish more comprehensive in vitro and in vivo models to expedite clinical translation.

Changes in Urinary Exosomal Nuclear Matrix Protein-22 in Dogs With Urothelial Carcinoma: A Pilot Study

BACKGROUND/AIM

Nuclear matrix protein-22 (NMP-22) is widely used in human medicine as a prognostic and diagnostic tool for urothelial carcinoma (UC). In addition, the use of urinary exosomes as a liquid biopsy tool is emerging for the diagnosis of certain types of cancer in human medicine. This study aimed to investigate the change in urinary exosomal NMP-22 for the diagnosis of UC in dogs.

PATIENTS AND METHODS

Among canine patients who visited the veterinary hospital, urine was collected from those whose owners provided consent. A total of 23 dogs (UC group, n=6; control group, n=17) were included in the analysis. After exosomes were isolated from the urine, NMP-22 was measured using enzyme-linked immunosorbent assay.

RESULTS

In the UC group, the expression of NMP-22 in urinary exosomes was significantly higher than that in non-UC groups (p<0.0001).

CONCLUSION

NMP-22 is significantly increased in exosomes in the urine of dogs diagnosed with UC, suggesting that urinary exosome NMP-22 can be considered as one of the liquid biopsy tools for diagnosing UC in dogs.

Comet-FISH analysis of urothelial cells. A screening opportunity for bladder cancer?

INTRODUCTION

Bladder cancer (BCa) is the most frequent cancer of the urinary tract, with more than 500,000 reported cases and nearly 200,000 related deaths yearly. Cystoscopy is the standard examination used for the initial diagnosis and follow-up of BCa in the noninvasive stage. However, the American Cancer Society does not include BCa screening in its list of recommended cancer screenings.

AREAS COVERED

Recently, several urine-based bladder tumor markers (UBBTMs) that identify genomic, transcriptomic, epigenetic, or protein alterations have been introduced, some of which have been approved by the Food and Drug Administration (FDA) to improve its diagnosis and surveillance. Several biomarkers have been found in the tissues and blood of individuals with BCa or predisposed to develop the disease, further enriching our information.

EXPERT OPINION

From a prevention perspective, alkaline Comet-FISH could be a valuable tool with broad potential for clinical application. Furthermore, a comet assay could be more beneficial for diagnosing and monitoring bladder cancer and determining individual susceptibility. Thus, we recommend further studies to understand the potential of this combined assay in the general population as a potential screening test and in patients initiated into the diagnostic process.

Extracellular vesicles in the context of Chagas Disease - A systematic review

Extracellular vesicle (EVs) traffic is considered an important cellular communication process between cells that can be part of a single organism or belong to different living beings. The relevance of EV-mediated cellular communication is increasingly studied and appreciated, especially in relation to pathological conditions, including parasitic disorders, in which the EV release and uptake processes have been documented. In the context of Chagas Disease (CD), EVs have been explored, however, current data have not been systematically revised in order to provide an overview of the published literature and the main results obtained thus far. In this systematic review, 25 studies involving the investigation of EVs in CD were identified. The studies involved Trypanosoma cruzi (Tc)-derived EVs (Tc-EVs), as well as EVs derived from T. cruzi-infected mammalian cells-derived EVs, mainly isolated by ultracentrifugation and poorly characterized. The objectives of the identified studies included the characterization of the protein and RNA cargo of Tc-EVs, as well as investigation of EVs in parasitic infections and immune-related processes. Overall, our systematic review reveals that EVs play critical roles in several mechanisms related to the interaction between T. cruzi and mammalian hosts, their contribution to immune system evasion by the parasite, and to chronic inflammation in the host. Future studies will benefit from the consolidation of isolation and characterization methods, as well as the elucidation of the role of EVs in CD.

Serum exosomal miR-146a-3p associates with disease severity and efficacy of sublingual immunotherapy in allergic rhinitis

BACKGROUND

Sublingual immunotherapy (SLIT) is an effective treatment for allergic rhinitis (AR), but its efficacy is variable among individuals. This study aimed to characterize serum exosome-derived microRNAs (miRNAs) and evaluate their abilities in predicting the efficacy of SLIT in AR.

METHODS

RNA sequencing was performed to explore differentially expressed exosomal miRNAs in serum exosomes between AR patients and healthy controls (HCs). Sequencing analysis results were verified in an independent cohort, and the correlations between the levels of exosome-derived miRNAs and disease severity were evaluated. The most promising miRNAs were further tested in two AR cohorts treated with SLIT to assess their abilities in predicting short and long-term efficacy, respectively.

RESULTS

The exosome-derived miRNAs profiling in the AR group was significantly different from the HC group, and differentially expressed genes were enriched and clustered in pathways such as PI3K-Akt and ErbB signalling pathways. The top three most significant miRNAs were verified by reverse transcription-polymerase chain reaction (qRT-PCR), and results showed that miR-146a-3p levels were significantly elevated in the AR group and correlated with the total and specific gE levels, the visual analogue scale of the total nasal symptom score (all p < 0.05). Further data in the first validation cohort suggested that miR-146a-3p levels were significantly downregulated in the effective group, and logistic regression showed that miR-146a-3p levels were associated with the short-term efficacy of SLIT(p < 0.05). The receiver operating characteristic (ROC) curve showed that miR-146a-3p could early predict SLIT efficacy (AUC = 0.669, p = 0.047). In the second validation cohort, miR-146a-3p levels were also decreased in the effective group and the ROC curve further confirmed its reliable accuracy in predicting the long-term efficacy of SLIT in AR patients (AUC = 0.749, p < 0.001).

CONCLUSION

Serum exosome-derived miRNAs may be involved in the development of AR and associated with its disease severity. Serum exosome-derived miR-146a-3p seems to be a novel biomarker for predicting the short and long-term efficacies of SLIT in AR patients.