A five-microRNA model (pCaP) for predicting prostate cancer aggressiveness using cell-free urine

Extracellular Microvesicle MicroRNAs and Imaging Metrics Improve the Detection of Aggressive Prostate Cancer: A Pilot Study

Background/Objectives: Prostate cancer (PCa) is the most diagnosed cancer in men worldwide. Early diagnosis of the disease provides better treatment options for these patients. Recent studies have demonstrated that plasma-based extracellular vesicle microRNAs (miRNAs) are functionally linked to cancer progression, metastasis, and aggressiveness. The use of magnetic resonance imaging (MRI) as the standard of care provides an overall assessment of prostate disease. Quantitative metrics (radiomics) from the MRI provide a better evaluation of the tumor and have been shown to improve disease detection. Methods: We conducted a study on prostate cancer patients, analyzing baseline blood plasma and MRI data. Exosomes were isolated from blood plasma samples to quantify miRNAs, while MRI scans provided detailed tumor morphology. Radiomics features from MRI and miRNA expression data were integrated to develop predictive models, which were evaluated using ROC curve analysis, highlighting the multivariable model's effectiveness. Results: Our findings indicate that the univariate feature-based model with the highest Youden's index achieved average areas under the receiver operating characteristic (ROC) curve of 0.76, 0.82, and 0.84 for miRNA, MR-T2W, and MR-ADC features, respectively, in identifying clinically aggressive (Gleason grade) disease. The multivariable feature-based model yielded an average area under the curve (AUC) of 0.88 and 0.95 using combinations of miRNA markers with imaging features in MR-ADC and MR-T2W, respectively. Conclusions: Our study demonstrates that combining miRNA markers with MRI-based radiomics improves the identification of clinically aggressive prostate cancer.

Exosomal Liquid Biopsy in Prostate Cancer: A Systematic Review of Biomarkers for Diagnosis, Prognosis, and Treatment Response

Prostate cancer, a leading cause of cancer-related mortality among men, often presents challenges in accurate diagnosis and effective monitoring. This systematic review explores the potential of exosomal biomolecules as noninvasive biomarkers for the diagnosis, prognosis, and treatment response of prostate cancer. A thorough systematic literature search through online public databases (Medline via PubMed, Scopus, and Web of science) using structured search terms and screening using predefined eligibility criteria resulted in 137 studies that we analyzed in this systematic review. We evaluated the findings from these clinical studies, revealing that the load of exosomes in the blood and urine of prostate cancer patients, which includes microRNAs (miRNAs), proteins, and lipids, demonstrates disease-specific changes. It also shows that some exosomal markers can differentiate between malignant and benign hyperplasia of the prostate, predict disease aggressiveness, and monitor treatment efficacy. Notably, miRNA emerged as the most frequently studied biomolecule, demonstrating superior diagnostic potential compared to traditional methods like prostate-specific antigen (PSA) testing. The analysis also highlights the pressing need for a standardised analytic approach through multi-centre studies to validate the full potential of exosomal biomarkers for the diagnosis and monitoring of prostate cancer.

Relationship between circulating miRNA-222-3p and miRNA-136-5p and the efficacy of docetaxel chemotherapy in metastatic castration-resistant prostate cancer patients

BACKGROUND

Metastatic castration-resistant prostate cancer is the most dangerous stage of prostate cancer, with a high mortality rate. Docetaxel chemotherapy is one of the most effective treatment methods currently, but some patients do not respond to chemotherapy. To avoid unnecessary toxicity in non-responders, this study explores the potential of circulating microRNAs as early biomarkers of docetaxel response in patients with metastatic castration-resistant prostate cancer.

METHODS

PC3 cells and DU145 cells were divided into the control, NC mimics, and miRNA-136-5p-mimics groups. Cell viability was measured using the CCK-8 assay. Cell apoptosis was determined by flow cytometry. Cell migration and invasion abilities were evaluated using the Transwell assay. Real-time quantitative PCR was used to measure the miRNA levels in cells and peripheral blood of patients. The miRNA-136-5p target genes were predicted by using the PITA, TargetScan, and miRanda databases. The target genes were analyzed with KEGG pathway analysis.

RESULTS

In both PC3 and DU145 cells, the miRNA-136-5p-mimics group exhibited significantly increased cell survival rates, migration and invasion numbers, and significantly decreased apoptosis rates than the control group (p < 0.05). The miRNA-222-3p and miRNA-136-5p levels were significantly increased in docetaxel-resistant PC3 and DU145 cells (p < 0.05). The levels of circulating miRNA-222-3p and miRNA-136-5p were significantly associated with docetaxel treatment (p < 0.05). Higher levels of miRNA-222-3p were observed in non-responsive patients (p < 0.05). The area under the curve for miRNA-222-3p was 0.76 (95%CI: 0.55-0.97), indicating its effectiveness as a predictive factor for non-responsive patients to docetaxel. Patients with high expression of miRNA-34c-5p after docetaxel chemotherapy had shorter overall survival times (P < 0.05). Bioinformatics analysis identified 110 potential target genes of miRNA-136-5p. KEGG revealed that these genes were mainly distributed in three pathways. Among them, the PI3K-AKT pathway was closely related to the metastasis of prostate cancer cells.

CONCLUSION

Our study demonstrates that miRNA-136-5p promotes the proliferation and invasion of PC3 and DU145 cells while inhibiting apoptosis. Circulating miRNA-222-3p may serve as a biomarker for early therapeutic response to docetaxel, and further clinical investigation is warranted. Additionally, miRNA-136-5p may have anti-cancer effects during docetaxel chemotherapy in metastatic castration-resistant prostate cancer.

Extracellular vesicle-derived biomarkers in prostate cancer care: Opportunities and challenges

Prostate cancer (PCa) is the second most prevalent cancer in men worldwide, presenting a significant global public health challenge that necessitates early detection and personalized treatment. Recently, non-invasive liquid biopsy methods have emerged as promising tools to provide insights into the genetic landscape of PCa and monitor disease progression, aiding decision-making at all stages. Research efforts have concentrated on identifying liquid biopsy biomarkers to improve PCa diagnosis, prognosis, and treatment prediction. This article reviews recent research advances over the last five years utilizing extracellular vesicles (EVs) as a natural biomarker library for PCa, and discusses the clinical translation of EV biomarkers, including ongoing trials and key implementation challenges. The findings underscore the transformative role of liquid biopsy, particularly EV-based biomarkers, in revolutionizing PCa diagnosis, prediction, and treatment.

MicroRNAs as promising diagnostic and prognostic markers for the human genitourinary cancer

Genitourinary cancer (GUC) represents more than one fifth of all human cancers. This makes the development of approaches to its early diagnosis an important task of modern biomedicine. Circulating microRNAs, short (17-25 nucleotides) non-coding RNA molecules found in human biological fluids and performing a regulatory role in the cell, are considered as promising diagnostic and prognostic biomarkers of cancers, including GUC. In this review we have considered the current state of research aimed at assessing microRNAs as biomarkers of such human GUC types as malignant tumors of the bladder, kidney, prostate, testicles, ovaries, and cervix. A special attention has been paid to studies devoted to the identification of microRNAs in urine as a surrogate "liquid biopsy" that may provide the simplest and cheapest approach to mass non-invasive screening of human GUC. The use of microRNA panels instead of single types of microRNA generally leads to higher sensitivity and specificity of the developed diagnostic tests. However, to date, work on the microRNAs assessment as biomarkers of human GUC is still of a research nature, and the further introduction of diagnostic tests based on microRNAs into practice requires successful clinical trials.

Small extracellular vesicles: Roles and clinical application in prostate cancer

Prostate cancer is a significant health problem in the United States. It is remarkably heterogenous, ranging from slow growing disease amenable to active surveillance to highly aggressive forms requiring active treatments. Therefore, being able to precisely determine the nature of disease and appropriately match patients to available and/or novel therapeutics is crucial to improve patients' overall outcome and quality of life. Recently small extracellular vesicles (sEVs), a subset of nanoscale membranous vesicles secreted by various cells, have emerged as important analytes for liquid biopsy and promising vehicles for drug delivery. sEVs contain various biomolecules such as genetic material, proteins, and lipids that recapitulate the characteristics and state of their donor cells. The application of existing and newly developed technologies has resulted in an increased depth of knowledge about biophysical structures, biogenesis, and functions of sEVs. In prostate cancer patients, tumor-derived sEVs can be isolated from biofluids, commonly urine and blood. They mediate intercellular signaling within the tumor microenvironment and distal organ-specific sites, supporting cancer initiation, progression, and metastasis. A mounting body of evidence suggests that sEV components can be potent biomarkers for prostate cancer diagnosis, prognosis, and prediction of disease progression and treatment response. Due to enhanced circulation stability and bio-barrier permeability, sEVs can be also used as effective drug delivery carriers to improve the efficacy and specificity of anti-tumor therapies. This review discusses recent studies on sEVs in prostate cancer and is focused on their role as biomarkers and drug delivery vehicles in the clinical management of prostate cancer.

Role of extracellular vesicles in castration-resistant prostate cancer

Prostate cancer (PCa) is a common health threat to men worldwide, and castration-resistant PCa (CRPC) is the leading cause of PCa-related deaths. Extracellular vesicles (EVs) are lipid bilayer compartments secreted by living cells that are important mediators of intercellular communication. EVs regulate the biological processes of recipient cells by transmitting heterogeneous cargoes, contributing to CRPC occurrence, progression, and drug resistance. These EVs originate not only from malignant cells, but also from various cell types within the tumor microenvironment. EVs are widely dispersed throughout diverse biological fluids and are attractive biomarkers derived from noninvasive liquid biopsy techniques. EV quantities and cargoes have been tested as potential biomarkers for CRPC diagnosis, progression, drug resistance, and prognosis; however, technical barriers to their clinical application continue to exist. Furthermore, exogenous EVs may provide tools for new therapies for CRPC. This review summarizes the current evidence on the role of EVs in CRPC.

Clinical Biofluid Assays for Prostate Cancer

This mini review summarizes the currently available clinical biofluid assays for PCa. The second most prevalent cancer worldwide is PCa. PCa is a heterogeneous disease, with a large percentage of prostate tumors being indolent, and with a relatively slow metastatic potential. However, due to the high case numbers, the absolute number of PCa-related deaths is still high. In fact, it causes the second highest number of cancer deaths in American men. As a first step for the diagnosis of PCa, the PSA test has been widely used. However, it has low specificity, which results in a high number of false positives leading to overdiagnosis and overtreatment. Newer derivatives of the original PSA test, including the Food and Drug Administration (FDA)-approved 4K (four kallikreins) and the PHI (Prostate Health Index) blood tests, have higher specificities. Tissue-based PCa tests are problematic as biopsies are invasive and have limited accuracy due to prostate tumor heterogeneity. Liquid biopsies offer a minimally or non-invasive choice for the patients, while providing a more representative reflection of the spatial heterogeneity in the prostate. In addition to the abovementioned blood-based tests, urine is a promising source of PCa biomarkers, offering a supplementary avenue for early detection and improved tumor classification. Four urine-based PCa tests are either FDA- or CLIA-approved: PCA3 (PROGENSA), ExoDX Prostate Intelliscore, MiPS, and SelectMDx. We will discuss these urine-based, as well as the blood-based, clinical PCa tests in more detail. We also briefly discuss a few promising biofluid marker candidates (DNA methylation, micro-RNAs) which are not in clinical application. As no single assay is perfect, we envision that a combination of biomarkers, together with imaging, will become the preferred practice.

The role of mir-151a-5p in tumorigenesis; A systematic review

BACKGROUND

Highly supported microRNAs (miRNAs) are key players in cancer development. Each of these miRNAs may act as an oncomir, a tumor-suppressor, or both in various cancers. Mir-151a-5p is believed to be one of these miRNAs with diverse roles. We have conducted this systematic review to clarify the role of mir-151a-5p in formation of various cancers.

METHODS AND MATERIALS

We searched for existing articles in PubMed, Web of Science, Cochrane, Scopus, and RNAcentral databases up to November 2022. A total of 23 articles were qualified and included in the present systematic review. This review is registered on JBI at https://jbi.global/systematic-review-register. Expression levels, diagnostic and prognostic values, biological processes, and targeted downstream genes are included.

RESULTS

Assembled data indicate the expression levels of mir-151a-5p vary from down- to up-regulated based on the type of the cancer. Its functional role depends on the genetic profile of cancerous tissue. Results mostly point to the oncogenic role of this miRNA in Pituitary adenomas, Acute Myeloid Leukemia (AML), Endometrial, Lung, Barrett's carcinogenesis, Colorectal, Myelodysplastic syndromes, Hepatocellular carcinoma and Breast cancers, as its inhibited targets seem to be controlling several signaling pathways, cell adhesion, and cell cycle. At the same time, tumor-suppressing role has also been observed only in Malignant Pleural Mesothelioma, Central Nerve System (CNS) lymphoma, Chronic Myeloid and Acute Lymphocytic Leukemia. Two types of cancers, prostate and colon, show contradictory results as there are studies supporting both up- and down-regulation in these cancers. Pituitary adenomas, Barrett's carcinogenesis and CNS lymphomas are top cancers diagnosed with mir-151-5p. However, prognostic feature is only applicable to Lung adenocarcinoma.

DISCUSSION

Based on the present findings and further studies in the future, mir-151a-5p may be used as diagnostic and prognostic biomarkers or even a therapeutic target in cancer studies.

DATA AVAILABILITY STATEMENT

The articles used in this study can be found with the defined search phrase in mentioned databases. A list of selected articles will be available on reasonable requests.

miR‑151a‑5p promotes the proliferation and metastasis of colorectal carcinoma cells by targeting AGMAT

Colorectal carcinoma (CRC) is one of the most common types of digestive cancer. It has been reported that the ectopic expression of microRNAs (miRs) plays a critical role in the occurrence and progression of CRC. In addition, it has also been suggested that miR‑151a‑5p may serve as a useful biomarker for the early detection and treatment of different types of cancer and particularly CRC. However, the specific effects and underlying mechanisms of miR‑151a‑5p in CRC remain elusive. The results of the current study demonstrated that miR‑151a‑5p was upregulated in CRC cell lines and clinical tissues derived from patients with CRC. Functionally, the results showed that miR‑151a‑5p significantly promoted CRC cell proliferation, migration and invasion. Additionally, dual luciferase reporter assays verified that agmatinase (AGMAT) was a direct target of miR‑151a‑5p and it was positively associated with miR‑151a‑5p expression. Mechanistically, miR‑151a‑5p could enhance the epithelial‑mesenchymal transition of CRC cells. Taken together, the results of the current study revealed a novel molecular mechanism indicating that the miR‑151a‑5p/AGMAT axis could serve a crucial role in the regulation of CRC and could therefore be considered as a potential therapeutic strategy for CRC.

Urinary extracellular vesicles miRNA-A new era of prostate cancer biomarkers

Prostate cancer is the second most common male cancer worldwide showing the highest rates of incidence in Western Europe. Although the measurement of serum prostate-specific antigen levels is the current gold standard in PCa diagnosis, PSA-based screening is not considered a reliable diagnosis and prognosis tool due to its lower sensitivity and poor predictive score which lead to a 22%-43% overdiagnosis, unnecessary biopsies, and over-treatment. These major limitations along with the heterogeneous nature of the disease have made PCa a very unappreciative subject for diagnostics, resulting in poor patient management; thus, it urges to identify and validate new reliable PCa biomarkers that can provide accurate information in regard to disease diagnosis and prognosis. Researchers have explored the analysis of microRNAs (miRNAs), messenger RNAs (mRNAs), small proteins, genomic rearrangements, and gene expression in body fluids and non-solid tissues in search of lesser invasive yet efficient PCa biomarkers. Although the presence of miRNAs in body fluids like blood, urine, and saliva initially sparked great interest among the scientific community; their potential use as liquid biopsy biomarkers in PCa is still at a very nascent stage with respect to other well-established diagnostics and prognosis tools. Up to date, numerous studies have been conducted in search of PCa miRNA-based biomarkers in whole blood or blood serum; however, only a few studies have investigated their presence in urine samples of which less than two tens involve the detection of miRNAs in extracellular vesicles isolated from urine. In addition, there exists some discrepancy around the identification of miRNAs in PCa urine samples due to the diversity of the urine fractions that can be targeted for analysis such as urine circulating cells, cell-free fractions, and exosomes. In this review, we aim to discuss research output from the most recent studies involving the analysis of urinary EVs for the identification of miRNA-based PCa-specific biomarkers.

Novel nomogram to predict biochemical recurrence-free survival after radical prostatectomy

PURPOSE

Conditional survival represents the probability of subsequent survival given that patients have already survived a certain length of time. Several models predict biochemical recurrence (BCR) after radical prostatectomy. However, none of them include postoperative prostate-specific antigen (PSA). We aimed to analyze BCR-free survival evolution over time and develop a nomogram incorporating the postoperative PSA value to predict BCR-free survival.

MATERIAL AND METHODS

We included patients treated with robot-assisted radical prostatectomy (RARP) for prostate cancer between 2009 and 2021 and calculated conditional survival. Cox proportional hazard regression analysis was used to assess the predictive variables of BCR. We developed a nomogram predicting BCR-free survival three and five years after RARP. We used c-index and decision curve analyses to compare the nomogram with the Cancer of the Prostate Risk Assessment post-Surgical (CAPRA-S) score.

RESULTS

We included 718 patients. The overall 3- and 5-year BCR-free survival rates were 85.1% and 75.7%, respectively. The 5-year BCR-free survival rates increased to 78.9%, 82.9%, 85.2%, and 84.7% for patients surviving 1, 2, 3, and 4 years without BCR, respectively. We developed a nomogram including the pathological Gleason score and T stage, positive surgical margin, PSA ≥ 0.05 ng/mL at one year, and lymph node involvement to predict BCR at 3 and 5 years postoperatively. Our nomogram presented a higher c-index (0.89) than the CAPRA-S score (0.78; p = 0.001) and a positive net benefit at 3 and 5 years postoperatively in the decision curve analyses.

CONCLUSION

The 5-year conditional BCR-free survival increased with survival without BCR. The developed nomogram significantly improved the accuracy in predicting BCR-free survival after RARP.

Development of a 7-miRNA prognostic signature for patients with bladder cancer

BACKGROUND

Bladder carcinoma (BC) represents one of the most prevalent malignant cancers, while predicting its clinical outcomes using traditional indicators is difficult. This study aimed to develop a miRNA signature for the prognostic prediction of patients with BC.

MATERIALS AND METHODS

MiRNAs that expressed differentially were identified between 413 BC and 19 non-tumor patients, whose prognostic values were evaluated using univariate and multivariate Cox regression analyses. The independent prognostic factors were screened out and were used to establish a signature. The risk score of the signature was calculated. Receiver operating characteristic (ROC) curves and Kaplan-Meier curves were used to verify the predictive performance of the miRNA signature and the risk score. A nomogram was constructed which integrated with the miRNA signature and clinical parameters. Experiments were performed.

RESULTS

7 prognosis related miRNAs were selected as independent risk factors, and a 7-miRNA signature was constructed, with an area under ROC (AUC) of 0.721. The 7-miRNA-signature based risk score acts as an independent prognostic factor, with satisfactory predictive performance (AUC = 0.744). Increased miR-337-3p expressions were detected in tumor samples and BC cell lines than in non-tumorigenic tissues and cell lines. Experiments suggested that miR-337-3p induces the proliferation, migration, and invasion of BC cells.

CONCLUSION

The constructed 7-miRNA signature is a promising biomarker for predicting the prognosis of patients with BC, and miR-337-3p may act as a candidate therapeutic target in BC treatments.

The Potential of MicroRNAs as Non-Invasive Prostate Cancer Biomarkers: A Systematic Literature Review Based on a Machine Learning Approach

Simple Summary

Prostate cancer (PCa) is the most common cancer in men worldwide. Screening and diagnosis are based on prostate-specific antigen (PSA) blood testing and digital rectal examination. Nevertheless, these methods are not specific and have a high risk of mistaken results. This has led to overtreatment and unnecessary radical therapy; thus, better prognostic tools are urgently needed. In this view, microRNAs (miRs) appear as potential non-invasive biomarkers for PCa diagnosis, prognosis, and therapy. As the scientific literature available in this field is huge and very often controversial, we identified and discussed three topics that characterize the investigated research area by combining the big data from the literature together with a novel machine learning approach. By analyzing the papers clustered into these topics we have offered a deeper understanding of the current research, which helps to contribute to the advancement of this research field.

Abstract

Background: Prostate cancer (PCa) is the second leading cause of cancer-related deaths in men. Although the prostate-specific antigen (PSA) test is used in clinical practice for screening and/or early detection of PCa, it is not specific, thus resulting in high false-positive rates. MicroRNAs (miRs) provide an opportunity as biomarkers for diagnosis, prognosis, and recurrence of PCa. Because the size of the literature on it is increasing and often controversial, this study aims to consolidate the state-of-art of relevant published research. Methods: A Systematic Literature Review (SLR) approach was applied to analyze a set of 213 scientific publications through a text mining method that makes use of the Latent Dirichlet Allocation (LDA) algorithm. Results and Conclusions: The result of this activity, performed through the MySLR digital platform, allowed us to identify a set of three relevant topics characterizing the investigated research area. We analyzed and discussed all the papers clustered into them. We highlighted that several miRs are associated with PCa progression, and that their detection in patients’ urine seems to be the more reliable and promising non-invasive tool for PCa diagnosis. Finally, we proposed some future research directions to help future scientists advance the field further.

Extracellular vesicles and particles impact the systemic landscape of cancer

Intercellular cross talk between cancer cells and stromal and immune cells is essential for tumor progression and metastasis. Extracellular vesicles and particles (EVPs) are a heterogeneous class of secreted messengers that carry bioactive molecules and that have been shown to be crucial for this cell-cell communication. Here, we highlight the multifaceted roles of EVPs in cancer. Functionally, transfer of EVP cargo between cells influences tumor cell growth and invasion, alters immune cell composition and function, and contributes to stromal cell activation. These EVP-mediated changes impact local tumor progression, foster cultivation of pre-metastatic niches at distant organ-specific sites, and mediate systemic effects of cancer. Furthermore, we discuss how exploiting the highly selective enrichment of molecules within EVPs has profound implications for advancing diagnostic and prognostic biomarker development and for improving therapy delivery in cancer patients. Altogether, these investigations into the role of EVPs in cancer have led to discoveries that hold great promise for improving cancer patient care and outcome.

Prostate Cancer Tumor Stroma: Responsibility in Tumor Biology, Diagnosis and Treatment

Simple Summary

The crosstalk between prostate stroma and its epithelium is essential to tissue homeostasis. Likewise, reciprocal signaling between tumor cells and the stromal compartment is required in tumor progression to facilitate or stimulate key processes such as cell proliferation and invasion. The aim of the present work was to review the current state of knowledge on the significance of tumor stroma in the genesis, progression and therapeutic response of prostate carcinoma. Additionally, we addressed the future therapeutic opportunities.

Abstract

Prostate cancer (PCa) is a common cancer among males globally, and its occurrence is growing worldwide. Clinical decisions about the combination of therapies are becoming highly relevant. However, this is a heterogeneous disease, ranging widely in prognosis. Therefore, new approaches are needed based on tumor biology, from which further prognostic assessments can be established and complementary strategies can be identified. The knowledge of both the morphological structure and functional biology of the PCa stroma compartment can provide new diagnostic, prognostic or therapeutic possibilities. In the present review, we analyzed the aspects related to the tumor stromal component (both acellular and cellular) in PCa, their influence on tumor behavior and the therapeutic response and their consideration as a new therapeutic target.

MiRNA biomarkers in cancers of the male reproductive system: are we approaching clinical application?

BACKGROUND

Specific cancer types face specific clinical management challenges. Owing to their stability, robustness and fast, easy, and cost-effective detection, microRNAs (miRNAs) are attractive candidate biomarkers to the clinic.

OBJECTIVES

Based on a comprehensive review of the relevant literature in the field, we explore the potential of miRNAs as biomarkers to answer relevant clinical dilemmas inherent to cancers of the male reproductive tract (prostate (PCa), testis (TGCTs) and penis (PeCa)) and identify some of the challenges/limitations hampering their widely application.

RESULTS AND DISCUSSION

We conclude that the use of miRNAs as biomarkers is at different stages for these distinct cancer types. While for TGCTs, miRNA-371a-3p is universally accepted to fill in important clinicals gaps and is moving fast towards clinical implementation, for PCa almost no overlap of miRNAs exists between studies, denoting the absence of a consistent miRNA biomarker, and for PeCa the field of miRNAs has just recently started, with only a few studies attempting to explore their clinical usefulness.

CONCLUSION

Technological advances influencing miRNA detection and quantification will be instrumental to continue to move forward with implementation of miRNAs in the clinic as biomarkers for non-invasive diagnosis, risk stratification, treatment monitoring and follow-up. This article is protected by copyright. All rights reserved.

Independent validation of a pre-specified four-kallikrein marker model for prediction of adverse pathology and biochemical recurrence

BACKGROUND

Accurate markers for prostate cancer (PC) risk stratification could aid decision-making for initial management strategies. The 4Kscore has an undefined role in predicting outcomes after radical prostatectomy (RP).

METHODS

We included 1476 patients with 4Kscore measured prior to RP at two institutions. The 4Kscore was assessed for prediction of adverse pathology at RP and biochemical recurrence (BCR) relative to a clinical model. We pre-specified that all analyses would be assessed in biopsy Grade Group 1 (GG1) or 2 (GG2) PC patients, separately.

RESULTS

The 4Kscore increased discrimination for adverse pathology in all patients (delta area under the receiver operative curve (AUC) 0.009, 95% confidence interval (CI) 0.002, 0.016; clinical model AUC 0.767), driven by GG1 (delta AUC 0.040, 95% CI 0.006, 0.073) rather than GG2 patients (delta AUC 0.005, 95% CI -0.012, 0.021). Adding 4Kscore improved prediction of BCR in all patients (delta C-index 0.014, 95% CI 0.007, 0.021; preop-BCR nomogram C-index 0.738), again with larger changes in GG1 than in GG2.

CONCLUSIONS

This study validates prior investigations on the use of 4Kscore in men with biopsy-confirmed PC. Men with GG1 PC and a high 4Kscore may benefit from additional testing to guide treatment selection. Further research is warranted regarding the value of the 4Kscore in men with biopsy GG2 PC.

Diagnostic and prognostic significance of extracellular vesicles in prostate cancer drug resistance: A systematic review of the literature

BACKGROUND

The clinical behavior of prostate cancer is highly heterogeneous, with most patients diagnosed with localized disease that successfully responds to surgery or radiotherapy. However, a fraction of men relapse after initial treatment because they develop drug resistance. The failure of anticancer drugs leaves resistant cancer cells to survive and proliferate, negatively affecting patient survival. Thus, drug resistance remains a significant obstacle to the effective treatment of prostate cancer patients. In this scenario, the involvement of extracellular vesicles (EVs) in intrinsic and acquired resistance have been reported in several tumors, and accumulating data suggests that their differential content can be used as diagnostic or prognostic factors. Thus, we propose a systematic study of literature to provide a snapshot of the current scenario regarding EVs as diagnostic and prognostic biomarkers resource in resistant prostate cancer.

METHODS

We performed the current systematic review according to PRISMA guidelines and comprehensively explored PubMed, EMBASE and Google Scholar databases to achieve the article search.

RESULTS

Thirty-three studies were included and investigated. Among all systematically reviewed EV biomarkers, we found mainly molecules with prognostic significance (61%), molecules with diagnostic relevance (18%), and molecules that serve both purposes (21%). Moreover, among all analyzed molecules isolated from EVs, proteins, mRNAs, and miRNAs emerged to be the most investigated and proposed as potential tools to diagnose or predict resistance/sensitivity to advanced PCa treatments.

DISCUSSION

Our analysis provides a snapshot of the current scenario regarding EVs as potential clinical biomarkers in resistant PCa. Nevertheless, despite many efforts, the use of EV biomarkers in PCa is currently at an early stage: none of the selected EV biomarkers goes beyond preclinical studies, and their translatability is yet far from clinical settings.

Extracellular vesicles as a source of prostate cancer biomarkers in liquid biopsies: a decade of research

Prostate cancer is a global cancer burden and considerable effort has been made through the years to identify biomarkers for the disease. Approximately a decade ago, the potential of analysing extracellular vesicles in liquid biopsies started to be envisaged. This was the beginning of a new exciting area of research investigating the rich molecular treasure found in extracellular vesicles to identify biomarkers for a variety of diseases. Vesicles released from prostate cancer cells and cells of the tumour microenvironment carry molecular information about the disease that can be analysed in several biological fluids. Numerous studies document the interest of researchers in this field of research. However, methodological issues such as the isolation of vesicles have been challenging. Remarkably, novel technologies, including those based on nanotechnology, show promise for the further development and clinical use of extracellular vesicles as liquid biomarkers. Development of biomarkers is a long and complicated process, and there are still not many biomarkers based on extracellular vesicles in clinical use. However, the knowledge acquired during the last decade constitutes a solid basis for the future development of liquid biopsy tests for prostate cancer. These are urgently needed to bring prostate cancer treatment to the next level in precision medicine.

Exosomal long noncoding RNA HOXD-AS1 promotes prostate cancer metastasis via miR-361-5p/FOXM1 axis

Development of distant metastasis is the main cause of deaths in prostate cancer (PCa) patients. Understanding the mechanism of PCa metastasis is of utmost importance to improve its prognosis. The role of exosomal long noncoding RNA (lncRNA) has been reported not yet fully understood in the metastasis of PCa. Here, we discovered an exosomal lncRNA HOXD-AS1 is upregulated in castration resistant prostate cancer (CRPC) cell line derived exosomes and serum exosomes from metastatic PCa patients, which correlated with its tissue expression. Further investigation confirmed exosomal HOXD-AS1 promotes prostate cancer cell metastasis in vitro and in vivo by inducing metastasis associated phenotype. Mechanistically exosomal HOXD-AS1 was internalized directly by PCa cells, acting as competing endogenous RNA (ceRNA) to modulate the miR-361-5p/FOXM1 axis, therefore promoting PCa metastasis. In addition, we found that serum exosomal HOXD-AS1 was upregulated in metastatic PCa patients, especially those with high volume disease. And it is correlated closely with Gleason Score, distant and nodal metastasis, Prostatic specific antigen (PSA) recurrence free survival, and progression free survival (PFS). This sheds a new insight into the regulation of PCa distant metastasis by exosomal HOXD-AS1 mediated miR-361-5p/FOXM1 axis, and provided a promising liquid biopsy biomarker to guide the detection and treatment of metastatic PCa.

Regulation of Neuroendocrine-like Differentiation in Prostate Cancer by Non-Coding RNAs

Neuroendocrine prostate cancer (NEPC) represents a variant of prostate cancer that occurs in response to treatment resistance or, to a much lesser extent, de novo. Unravelling the molecular mechanisms behind transdifferentiation of cancer cells to neuroendocrine-like cancer cells is essential for development of new treatment opportunities. This review focuses on summarizing the role of small molecules, predominantly microRNAs, in this phenomenon. A published literature search was performed to identify microRNAs, which are reported and experimentally validated to modulate neuroendocrine markers and/or regulators and to affect the complex neuroendocrine phenotype. Next, available patients’ expression datasets were surveyed to identify deregulated microRNAs, and their effect on NEPC and prostate cancer progression is summarized. Finally, possibilities of miRNA detection and quantification in body fluids of prostate cancer patients and their possible use as liquid biopsy in prostate cancer monitoring are discussed. All the addressed clinical and experimental contexts point to an association of NEPC with upregulation of miR-375 and downregulation of miR-34a and miR-19b-3p. Together, this review provides an overview of different roles of non-coding RNAs in the emergence of neuroendocrine prostate cancer.

Identification of colorectal cancer associated biomarkers: an integrated analysis of miRNA expression

Colorectal cancer is one of the leading causes of cancer-related deaths worldwide. This complex disease still holds severe problems concerning diagnosis due to the high invasiveness nature of colonoscopy and the low accuracy of the alternative diagnostic methods. Additionally, patient heterogeneity even within the same stage is not properly reflected in the current stratification system. This scenario highlights the need for new biomarkers to improve non-invasive screenings and clinical management of patients. MicroRNAs (miRNAs) have emerged as good candidate biomarkers in cancer as they are stable molecules, easily measurable and detected in body fluids thus allowing for non-invasive diagnosis and/or prognosis. In this study, we performed an integrated analysis first using 4 different datasets (discovery cohorts) to identify miRNAs associated with colorectal cancer development, unveil their role in this disease by identifying putative targets and regulatory networks and investigate their ability to serve as biomarkers. We have identified 26 differentially expressed miRNAs which interact with frequently deregulated genes known to participate in commonly altered pathways in colorectal cancer. Most of these miRNAs have high diagnostic power, and their prognostic potential is evidenced by panels of 5 miRNAs able to predict the outcome of stage II and III colorectal cancer patients. Notably, 8 miRNAs were validated in three additional independent cohorts (validation cohorts) including a plasma cohort thus reinforcing the value of miRNAs as non-invasive biomarkers.

miRNA-Based Potential Biomarkers and New Molecular Insights in Ulcerative Colitis

Ulcerative colitis (UC) is a chronic non-specific inflammatory bowel disease, which usually manifests as abdominal pain, diarrhea and hematochezia. The disease often recurs and is difficult to cure. At present, the pathogenesis is not clear, but it is believed that the disease is caused by a complex interaction among immunity, heredity, environment and intestinal microflora disorders. MicroRNA (miRNA) is endogenous single-stranded non-coding RNA of 17–25 nucleotides (nts). They target the 3'Untranslated Region of a target gene and inhibit or degrade the target gene according to the extent of complementary bases. As important gene expression regulators, miRNAs are involved in regulating the expression of most human genes, and play an important role in the pathogenesis of many autoimmune diseases including UC. Studies in recent years have illustrated that abnormal expression of miRNA occurs very early in disease pathogenesis. Moreover, this abnormal expression is highly related to disease activity of UC and colitis-associated cancer, and involves virtually all key UC-related mechanisms, such as immunity and intestinal microbiota dysregulation. Recently, it was discovered that miRNA is highly stable outside the cell in the form of microvesicles, exosomes or apoptotic vesicles, which raises the possibility that miRNA may serve as a novel diagnostic marker for UC. In this review, we summarize the biosynthetic pathway and the function of miRNA, and summarize the usefulness of miRNA for diagnosis, monitoring and prognosis of UC. Then, we described four types of miRNAs involved in regulating the mechanisms of UC occurrence and development: 1) miRNAs are involved in regulating immune cells; 2) affect the intestinal epithelial cells barrier; 3) regulate the homeostasis between gut microbiota and the host; and 4) participate in the formation of tumor in UC. Altogether, we aim to emphasize the close relationship between miRNA and UC as well as to propose that the field has value for developing potential biomarkers as well as therapeutic targets for UC.

Emerging roles and mechanisms of microRNA‑222‑3p in human cancer (Review)

MicroRNAs (miRNAs/miRs) are a class of small non‑coding RNAs that maintain the precise balance of various physiological processes through regulating the function of target mRNAs. Dysregulation of miRNAs is closely associated with various types of human cancer. miR‑222‑3p is considered a canonical factor affecting the expression and signal transduction of multiple genes involved in tumor occurrence and progression. miR‑222‑3p in human biofluids, such as urine and plasma, may be a potential biomarker for the early diagnosis of tumors. In addition, miR‑222‑3p acts as a prognostic factor for the survival of patients with cancer. The present review first summarizes and discusses the role of miR‑222‑3p as a biomarker for diverse types of cancers, and then focuses on its essential roles in tumorigenesis, progression, metastasis and chemoresistance. Finally, the current understanding of the regulatory mechanisms of miR‑222‑3p at the molecular level are summarized. Overall, the current evidence highlights the crucial role of miR‑222‑3p in cancer diagnosis, prognosis and treatment.

Circulating miRNAs Act as Diagnostic Biomarkers for Bladder Cancer in Urine

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

The discriminative ability of Prostate Health Index to detect prostate cancer is enhanced in combination with miR-222-3p

BACKGROUND

There is an urgent need for better prostate cancer (PCa) biomarkers due to the low specificity of prostate specific antigen (PSA).

OBJECTIVE

Prostate Health Index (PHI) is an advanced PSA-based test for early detection of PCa. The present study aim was to investigate the potential improvement of diagnostic accuracy of PHI by its combination with suitable discriminative microRNAs (miRNAs).

METHODS

A two-phase study was performed. In a discovery phase, a panel of 177 miRNAs was measured in ten men with biopsy proven PCa and ten men with histologically no evidence of malignancy (NEM). These results were validated in a second phase including 25 patients in each group. The patients of all groups were matched regarding their PSA values and PHI were measured.

RESULTS

Based on data in the discovery phase, four elevated miRNAs were selected as potential miRNA candidates for further validation. A combination of miR-222-3p as the best discriminative miRNA with PHI extended the diagnostic accuracy of PHI from an AUC value of 0.690 to 0.787 and resulted in a sensitivity of 72.0% and a specificity of 84.0%.

CONCLUSION

Circulating microRNAs show useful diagnostic potential in combination with common used biomarkers to enhance their diagnostic power.

Extracellular vesicles in prostate cancer: a narrative review

Over the past decade, there has been remarkable progress in prostate cancer biomarker discovery using urine- and blood-based assays. A liquid biopsy is a minimally invasive procedure to investigate the cancer-related molecules in circulating tumor cells (CTCs), cell-free DNA, and extracellular vesicles (EVs). Liquid biopsies have the advantage of detecting heterogeneity as well as acquired resistance in cancer. EVs are cell-derived vesicles enclosed by a lipid bilayer and contain various molecules, such as nucleic acids, proteins, and lipids. In patients with cancer, EVs derived from tumors can be isolated from urine, plasma, and serum. The advances in isolation techniques provide the opportunity to use EVs as biomarkers in the clinic. Emerging evidence suggests that EVs can be useful biomarkers for the diagnosis of prostate cancer, especially high-grade cancer. EVs can also be potent biomarkers for the prediction of disease progression in patients with castration-resistant prostate cancer (CRPC). EVs shed from cancer and stromal cells are involved in the development of tumor microenvironments, enhancing cancer progression, metastasis, and drug resistance. Here, we provide an overview of the use of EVs for the diagnosis of clinically significant prostate cancer as well as for predicting disease progression. We also discuss the biological function of EVs, which regulate cancer progression.

EWI-2 controls nucleocytoplasmic shuttling of EGFR signaling molecules and miRNA sorting in exosomes to inhibit prostate cancer cell metastasis

Early and accurate diagnosis of prostate cancer (PCa) is extremely important, as metastatic PCa remains hard to treat. EWI-2, a member of the Ig protein subfamily, is known to inhibit PCa cell migration. In this study, we found that EWI-2 localized on both the cell membrane and exosomes regulates the distribution of miR-3934-5p between cells and exosomes. Interestingly, we observed that EWI-2 is localized not only on the plasma membrane but also on the nuclear envelope (nuclear membrane), where it regulates the nuclear translocation of signaling molecules and miRNA. Collectively, these functions of EWI-2 found in lipid bilayers appear to regulate PCa cell metastasis through the epidermal growth factor receptor-mitogen-activated protein kinase-extracellular-signal-regulated kinase (EGFR-MAPK-ERK) pathway. Our research provides new insights into the molecular function of EWI-2 on PCa metastasis, and highlights EWI-2 as a potential PCa biomarker.

High-Throughput and Automated Acoustic Trapping of Extracellular Vesicles to Identify microRNAs With Diagnostic Potential for Prostate Cancer

Molecular profiling of extracellular vesicles (EVs) offers novel opportunities for diagnostic applications, but the current major obstacle for clinical translation is the lack of efficient, robust, and reproducible isolation methods. To bridge that gap, we developed a microfluidic, non-contact, and low-input volume compatible acoustic trapping technology for EV isolation that enabled downstream small RNA sequencing. In the current study, we have further automated the acoustic microfluidics-based EV enrichment technique that enables us to serially process 32 clinical samples per run. We utilized the system to enrich EVs from urine collected as the first morning void from 207 men referred to 10-core prostate biopsy performed the same day. Using automated acoustic trapping, we successfully enriched EVs from 199/207 samples (96%). After RNA extraction, size selection, and library preparation, a total of 173/199 samples (87%) provided sufficient materials for next-generation sequencing that generated an average of 2 × 10⁶ reads per sample mapping to the human reference genome. The predominant RNA species identified were fragments of long RNAs such as protein coding and retained introns, whereas small RNAs such as microRNAs (miRNA) accounted for less than 1% of the reads suggesting that partially degraded long RNAs out-competed miRNAs during sequencing. We found that the expression of six miRNAs was significantly different (P_adj < 0.05) in EVs isolated from patients found to have high grade prostate cancer [ISUP 2005 Grade Group (GG) 4 or higher] compared to those with GG3 or lower, including those with no evidence of prostate cancer at biopsy. These included miR-23b-3p, miR-27a-3p, and miR-27b-3p showing higher expression in patients with GG4 or high grade prostate cancer, whereas miR-1-3p, miR-10a-5p, and miR-423-3p had lower expression in the GG4 PCa cases. Cross referencing our differentially expressed miRNAs to two large prostate cancer datasets revealed that the putative tumor suppressors miR-1, miR-23b, and miR-27a are consistently deregulated in prostate cancer. Taken together, this is the first time that our automated microfluidic EV enrichment technique has been found to be capable of enriching EVs on a large scale from 900 μl of urine for small RNA sequencing in a robust and disease discriminatory manner.

Clinical significance and potential molecular mechanism of miRNA-222-3p in metastatic prostate cancer

The clinical significance and underlying molecular mechanism of miRNA-222-3p in metastatic prostate cancer (MPCa) remain unclear. The present study used a large number of cases (n = 1,502) based on miRNA chip and miRNA sequencing datasets to evaluate the expression and diagnostic potential of miRNA-222-3p in MPCa. We applied a variety of meta-analytic methods, including forest maps, sensitivity analysis, subgroup analysis and summary receiver operating characteristic curves, to prove the final results. MiRNA-222-3p was reduced in MPCa and had a moderate diagnostic potential in MPCa. We screened 118 miRNA-222-3p targets using three different methods including miRNA-222-3p transfected MPCa cell lines, online prediction databases and differently upregulated genes in MPCa. Moreover, functional enrichment analysis performed to explore the potential molecular mechanism of miRNA-222-3p showed that the potential target genes of miRNA-222-3p were significantly enriched in the p53 signal pathway. In the protein–protein interaction network analysis, SNAP91 was identified as a hub gene that may be closely related to MPCa. Gene chip and RNA sequencing datasets containing 1,237 samples were used to determine the expression level and diagnostic potential of SNAP91 in MPCa. SNAP91 was found to be overexpressed in MPCa and had a moderate diagnostic potential in MPCa. In addition, miRNA-222-3p expression was negatively correlated with SNAP91 expression in MPCa (r = −0.636, P = 0.006). These results demonstrated that miRNA-222-3p might play an important role in MPCa by negatively regulating SNAP91 expression. Thus, miRNA-222-3p might be a potential biomarker and therapeutic target of MPCa.

The nanostructured secretome

The term secretome, which traditionally strictly refers to single proteins, should be expanded to also include the great variety of nanoparticles secreted by cells (secNPs) into the extracellular space, which ranges from high-density lipoproteins of a few nanometers to extracellular vesicles and fat globules of hundreds of nanometers. Widening the definition is urged by the ever-increasing understanding of the role of secNPs as regulators/mediators of key physiological and pathological processes, which also puts them in the running as breakthrough cell-free therapeutics and diagnostics. "Made by cells for cells", secNPs are envisioned as a sweeping paradigm shift in nanomedicine, promising to overcome the limitations of synthetic nanoparticles by unsurpassed circulation and targeting abilities, precision and sustainability. From a longer/wider perspective, advanced manipulation would possibly make secNPs available as building blocks for future "biogenic" nanotechnology. However, the current knowledge is fragmented and sectorial (the majority of the studies being focused on a specific biological and/or medical aspect of a given secNP class or subclass), the understanding of the nanoscale and interfacial properties is limited and the development of bioprocesses and regulatory initiatives is in the early days. We believe that new multidisciplinary competencies and synergistic efforts need to be attracted and augmented to move forward. This review will contribute to the effort by attempting for the first time to rationally gather and elaborate secNPs and their traits into a unique concise framework - from biogenesis to colloidal properties, engineering and clinical translation - disclosing the overall view and easing comparative analysis and future exploitation.

Profiling of Circulating microRNAs in Prostate Cancer Reveals Diagnostic Biomarker Potential

Early detection of prostate cancer (PC) is paramount as localized disease is generally curable, while metastatic PC is generally incurable. There is a need for improved, minimally invasive biomarkers as current diagnostic tools are inaccurate, leading to extensive overtreatment while still missing some clinically significant cancers. Consequently, we profiled the expression levels of 92 selected microRNAs by RT-qPCR in plasma samples from 753 patients, representing multiple stages of PC and non-cancer controls. First, we compared plasma miRNA levels in patients with benign prostatic hyperplasia (BPH) or localized prostate cancer (LPC), versus advanced prostate cancer (APC). We identified several dysregulated microRNAs with a large overlap of 59 up/down-regulated microRNAs between BPH versus APC and LPC versus APC. Besides identifying several novel PC-associated dysregulated microRNAs in plasma, we confirmed the previously reported upregulation of miR-375 and downregulation of miR-146a-5p. Next, by randomly splitting our dataset into a training and test set, we identified and successfully validated a novel four microRNA diagnostic ratio model, termed bCaP (miR-375*miR-33a-5p/miR-16-5p*miR-409-3p). Combined in a model with prostate specific antigen (PSA), digital rectal examination status, and age, bCaP predicted the outcomes of transrectal ultrasound (TRUS)-guided biopsies (negative vs. positive) with greater accuracy than PSA alone (Training: area under the curve (AUC), model = 0.84; AUC, PSA = 0.63. Test set: AUC, model = 0.67; AUC, PSA = 0.56). It may be possible in the future to use this simple and minimally invasive bCaP test in combination with existing clinical parameters for a more accurate selection of patients for prostate biopsy.

A Three-Gene Classifier Associated With MicroRNA-Mediated Regulation Predicts Prostate Cancer Recurrence After Radical Prostatectomy

BACKGROUND AND OBJECTIVE

After radical prostatectomy (RP), prostate cancer (PCa) patients may experience biochemical recurrence (BCR) and clinical recurrence, which remains a dominant issue in PCa treatment. The purpose of this study was to identify a protein-coding gene classifier associated with microRNA (miRNA)-mediated regulation to provide a comprehensive prognostic index to predict PCa recurrence after RP.

METHODS

Candidate classifiers were constructed using two machine-learning algorithms (a least absolute shrinkage and selector operation [LASSO]-based classifier and a decision tree-based classifier) based on a discovery cohort (n = 156) from The Cancer Genome Atlas (TCGA) database. After selecting the LASSO-based classifier based on the prediction accuracy, both an internal validation cohort (n = 333) and an external validation cohort (n = 100) were used to examined the classifier using survival analysis, time-dependent receiver operating characteristic (ROC) curve analysis, and univariate and multivariate Cox proportional hazards regression analyses. Functional enrichment analysis of co-expressed genes was carried out to explore the underlying moleculer mechanisms of the genes included in the classifier.

RESULTS

We constructed a three-gene classifier that included FAM72B, GNE, and TRIM46, and we identified four upstream prognostic miRNAs (hsa-miR-133a-3p, hsa-miR-222-3p, hsa-miR-1301-3p, and hsa-miR-30c-2-3p). The classifier exhibited a remarkable ability (area under the curve [AUC] = 0.927) to distinguish PCa patients with high and low Gleason scores in the discovery cohort. Furthermore, it was significantly associated with clinical recurrence (p < 0.0001, log rank statistic = 20.7, AUC = 0.733) and could serve as an independent prognostic factor of recurrence-free survival (hazard ratio: 1.708, 95% CI: 1.180-2.472, p < 0.001). Additionally, it was a predictor of BCR according to BCR-free survival analysis (p = 0.0338, log rank statistic = 4.51).

CONCLUSIONS

The three-gene classifier associated with miRNA-mediated regulation may serve as a novel prognostic biomarker for PCa patients after RP.