Novel diagnostic and prognostic classifiers for prostate cancer identified by genome-wide microRNA profiling

Elevated miR-221-3p inhibits epithelial-mesenchymal transition and biochemical recurrence of prostate cancer via targeting KPNA2: an evidence-based and knowledge-guided strategy

BACKGROUND

Prostate cancer (PCa) is commonly occurred among males worldwide and its prognosis could be influenced by biochemical recurrence (BCR). MicroRNAs (miRNAs) are functional regulators in carcinogenesis, and miR-221-3p was reported as one of the significant candidates deregulated in PCa. However, its regulatory pattern in PCa BCR across literature reports was not consistent, and the targets and mechanisms in PCa malignant transition and BCR are less explored.

METHODS

In this study, an evidence-based and knowledge-guided approach was proposed to decipher the role and mechanism of miR-221-3p in PCa development. First, the literature-reported inconsistency between miR-221-3p and PCa BCR was quantitatively measured by meta-analysis. Then a knowledge-guided network strategy was applied to prioritize key targets of miR-221-3p in PCa progression based both on topological and functional characterization of genes in multi-omics miRNA-mRNA and protein-protein interaction networks. Finally, a key gene was computationally identified and experimentally validated using cell line and clinical samples through EdU assay, scratch assay, transwell assay, dual-luciferase reporter assay and the epithelial-to-mesenchymal transition (EMT)-related analysis.

RESULTS

Down-regulation of miR-221-3p was correlated with a lower biochemical recurrence-free survival (BRFS) in PCa (HR: 0.72, 95%, CI: 0.64-0.81, P < 0.00001). A significant down-regulation of miR-221-3p was observed in most of the PCa cells compared with the normal control. KPNA2 was identified as a key target of miR-221-3p and it was over-expressed in all the PCa cells and human PCa tissues. Moreover, elevated miR-221-3p inhibited the proliferation, migration, invasion, and EMT of PCa cells in vitro via directly and negatively mediating KPNA2 expression.

CONCLUSIONS

miR-221-3p down-regulation was a risk factor for PCa BRFS, and its over-expression could inhibit the malignant phenotype and EMT of PCa cells by directly targeting KPNA2. Translational and personalized applications of the findings will be conducted in the future.

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.

Integrated grade-wise profiling analysis reveals potential plasma miR-373-3p as prognostic indicator in Prostate Cancer & its target KPNA2

Background

Plasma microRNAs (miRNAs) have recently garnered attention for their potential as stable biomarkers in the context of Prostate Cancer (PCa), demonstrating established associations with tumor grade, biochemical recurrence (BCR), and metastasis. This study seeks to assess the utility of plasma miRNAs as prognostic indicators for distinguishing between high-grade and low-grade PCa, and to explore their involvement in PCa pathogenesis.

Methodology

We conducted miRNA profiling in both plasma and tissue specimens from patients with varying PCa grades. Subsequently, the identified miRNAs were validated in a substantial independent PCa cohort. Furthermore, we identified and confirmed the gene targets of these selected miRNAs through Western blot analysis.

Results

In our plasma profiling investigation, we identified 98, 132, and 154 differentially expressed miRNAs (DEMs) in high-grade PCa vs. benign prostatic hyperplasia (BPH), low-grade PCa vs. BPH, and high-grade PCa vs. low-grade PCa, respectively. Our tissue profiling study revealed 111, 132, and 257 statistically significant DEMs for the same comparisons. Notably, miR-373-3p emerged as the sole consistently dysregulated miRNA in both plasma and tissue samples of PCa. This miRNA displayed significant overexpression in plasma and tissue samples, with fold changes of 3.584 ± 0.5638 and 8.796 ± 1.245, respectively. Furthermore, we observed a significant reduction in KPNA2 protein expression in PCa.

Conclusion

Our findings lend support to the potential of plasma miR-373-3p as a valuable biomarker for predicting and diagnosing PCa. Additionally, this miRNA may contribute to the progression of PCa by inhibiting KPNA2 expression, shedding light on its role in the disease.

TP53 gene implications in prostate cancer evolution: potential role in tumor classification

Background and aims

Prostate adenocarcinoma (PRAD) is a complex disease that can be driven by alterations in both coding and noncoding genes. Recent research has identified coding and non-coding genes that are considered to play important roles in prostate cancer evolution and which may be used as biomarkers for disease diagnosis, prognosis, and treatment. TP53 is a critical hub gene in prostate cancer. Advanced studies have demonstrated the crosstalk between coding and non-coding RNAs, particularly microRNAs (miRNAs).

Methods

In this study, we investigated the roundabout of TP53 and their regulatory miRNAs (miR-15a-5p, miR-34a-5p, and miR-141-3p) based on the TCGA data set. We validated an additional patient cohort of 28 matched samples of patients with PRAD at tissue and plasma level.

Results

Therefore, using the UALCAN online database, we evaluated the expression level in PRAD of these genes revealing overexpression of TP53. qRT-PCR validation step endorsed the expression level for these genes. Additionally, we evaluated the expression level of the four key miRNAs (miR-15a-5p, miR-34a-5p, and miR-141-3p) interconnected as a network at tissue and plasma levels.

Conclusions

Through these results, we demonstrated the essential function of TP53 and its associated miRNAs that play a significant role in tumor control, highlighting miRNAs' potential as future therapeutic targets and biomarkers with important implications in managing prostate cancer.

The role of microRNA-185 in the pathogenesis of human diseases: A focus on cancer

MicroRNAs (miRNAs) are a widely-studied class of non-coding RNAs characterized by their short length (18-25 nucleotides). The precise functions of miRNAs are not well-elucidated; however, an increasing number of studies suggest their involvement in various physiologic processes and deregulation in pathologic conditions. miRNA-185 (miR-185) is among the mostly-studied miRNAs in human diseases, which is found to play putative roles in conditions like metabolic disorders, asthma, frailty, schizophrenia, and hepatitis. Notably, many cancer studies report the downregulation of miR-185 in cell lines, tumor tissues, and plasma specimens of patients, while it demonstrates a suppressing role on the malignant properties of cancer cells in vitro and in vivo. Accordingly, miR-185 can be considered a tumor suppressor miRNA in human malignancies, while a few studies also report inconsistent findings. Being suggested as a prognostic/diagnostic biomarker, mi-185 is also found to offer clinical potentials, particularly for early diagnosis and prediction of the prognosis of cancer patients. In this review, we have outlined the studies that have evaluated the functions and clinical significance of miR-185 in different human diseases with a particular focus on cancer.

Cancer Stem Cells and Prostate Cancer: A Narrative Review

Cancer stem cells (CSCs) are a small and elusive subpopulation of self-renewing cancer cells with the remarkable ability to initiate, propagate, and spread malignant disease. In the past years, several authors have focused on the possible role of CSCs in PCa development and progression. PCa CSCs typically originate from a luminal prostate cell. Three main pathways are involved in the CSC development, including the Wnt, Sonic Hedgehog, and Notch signaling pathways. Studies have observed an important role for epithelial mesenchymal transition in this process as well as for some specific miRNA. These studies led to the development of studies targeting these specific pathways to improve the management of PCa development and progression. CSCs in prostate cancer represent an actual and promising field of research.

Differential Expression of miRNAs Contributes to Tumor Aggressiveness and Racial Disparity in African American Men with Prostate Cancer

Prostate cancer is the leading cancer in incidence and second leading cause of cancer mortality in US men. African American men have significantly higher incidence and mortality rates from prostate cancer than European American men. Previous studies reported that the disparity in prostate cancer survival or mortality can be explained by different biological backgrounds. microRNAs (miRNAs) regulate gene expression of their cognate mRNAs in many cancers. Therefore, miRNAs may be a potentially promising diagnostic tool. The role of miRNAs in prostate cancer aggressiveness and racial disparity has not been fully established. The goal of this study is to identify miRNAs associated with aggressiveness and racial disparity in prostate cancer. Here we report miRNAs that are associated with tumor status and aggressiveness in prostate cancer using a profiling approach. Further, downregulated miRNAs in African American tissues were confirmed by qRT-PCR. These miRNAs have also been shown to negatively regulate the expression of the androgen receptor in prostate cancer cells. This report provides a novel insight into understanding tumor aggressiveness and racial disparities of prostate cancer.

Using Small Non-Coding RNAs in Extracellular Vesicles of Semen as Biomarkers of Male Reproductive System Health: Opportunities and Challenges

Reproductive dysfunction and urogenital malignancies represent a serious health concern in men. This is in part as a result of the absence of reliable non-invasive tests of diagnosis/prognosis. Optimizing diagnosis and predicting the patient’s prognosis will affect the choice of the most appropriate treatment and therefore increase the chances of success and the result of therapy, that is, it will lead to a more personalized treatment of the patient. This review aims firstly to critically summarize the current knowledge of the reproductive roles played by extracellular vesicle small RNA components, which are typically altered in diseases affecting the male reproductive tract. Secondly, it aims to describe the use of semen extracellular vesicles as a non-invasive source of sncRNA-based biomarkers for urogenital diseases.

Potential plasma microRNAs signature miR-190b-5p, miR-215-5p and miR-527 as non-invasive biomarkers for prostate cancer

BackgroundProstate cancer (PCa) is the most prevalent (20%) pathological cancer among males globally. MicroRNAs (miRNAs) are short (19-22 nucleotide), conserved, noncoding molecules that regulate post-transcriptional processes either by repressing or degrading mRNA or by translation inhibition binding to complementary sites on mRNA. The goal of this study was to find out whether differentially expressed microRNA (DEM) could be used as a potential marker in the prognosis and diagnosis of PCa.MethodologyThe miRNAs profiling was done both from plasma and tissue samples of the same PCa patient (n = 3) by real-time quantitative PCR (qRT-PCR) and compared with BPH (benign prostatic hyperplasia) patients (n = 3) as controls and further validation of selected miRNAs.ResultsWe found 55 significant overexpressed DEMs, 44 significant underexpressed DEMs in plasma and 6 significant overexpressed DEMs, 27 significant underexpressed DEMs in tissue compared between PCa and BPH. Furthermore, there were eight miRNAs namely miR-190b, miR-215, miR-300, miR-329, miR-504, miR-525-3p, miR-527, miR-548a-3p found to be significantly differentially expressed in plasma and tissue samples via profiling, however only three showed concordant expression. After validation, miR-190b-5p were shown to be significantly downexpressed with fold changes of 0.4177 (p value - 0.0072) and 0.7264 (p value - 0.0143) in plasma and tissue samples, respectively. The expression of miR-215-5p was shown to be significantly overexpressed with fold change of 1.820 (p - 0.0016) and 1.476 (p - 0.0407) in plasma and tissue samples, respectively. Furthermore, miR-527 was shown to be significantly downexpressed with fold changes of 0.6018 (p - 0.0095) and 0.6917 (p - 0.0155) in plasma and tissue samples, respectively.ConclusionAccording to our findings, plasma miR-190b-5p, miR-215-5p, miR-527 levels alteration is consistently linked with PCa tissue. For establishing significant miRNAs as biomarkers, additional research of a larger population is needed.

Biomarkers for the Detection and Risk Stratification of Aggressive Prostate Cancer

Current strategies for the clinical management of prostate cancer are inadequate for a precise risk stratification between indolent and aggressive tumors. Recently developed tissue-based molecular biomarkers have refined the risk assessment of the disease. The characterization of tissue biopsy components and subsequent identification of relevant tissue-based molecular alterations have the potential to improve the clinical decision making and patient outcomes. However, tissue biopsies are invasive and spatially restricted due to tumor heterogeneity. Therefore, there is an urgent need for complementary diagnostic and prognostic options. Liquid biopsy approaches are minimally invasive with potential utility for the early detection, risk stratification, and monitoring of tumors. In this review, we focus on tissue and liquid biopsy biomarkers for early diagnosis and risk stratification of prostate cancer, including modifications on the genomic, epigenomic, transcriptomic, and proteomic levels. High-risk molecular alterations combined with orthogonal clinical parameters can improve the identification of aggressive tumors and increase patient survival.

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.

A Study to Investigate the Role of Noncoding RNA miR146 Alpha as a Potential Biomarker in Prostate Cancer

There is a need for additional biomarkers for the diagnosis and prognosis of prostate cancer. MicroRNAs are a class of non-protein coding RNA molecules that are frequently dysregulated in different cancers including prostate cancer and show promise as diagnostic biomarkers and targets for therapy. Here we describe the role of micro RNA 146 a (miR-146a) which may serve as a diagnostic marker for prostate cancer, as indicated from the data presented in this report. Also, a pilot study indicated differential expression of miR-146a in prostate cancer cell lines and tissues from different racial groups. This report provides a novel insight into understanding the prostate carcinogenesis.

miRNAs as molecular biomarkers for prostate cancer

MicroRNAs (miRNAs) are short noncoding RNA able to regulate specific mRNA stability, thus influencing target gene expression. Disrupted levels of several miRNA have been associated with prostate cancer, the leading cause of cancer death among men and the fifth leading cause of death worldwide. Here, we investigated whether miR-145, miR-148, and miR-185 circulating levels in plasma could be used as molecular biomarkers, to allow distinguishing between individuals with benign prostatic hyperplasia, precancerous lesion, and prostate cancer. In this study, we recruited 170 urological clinic patients with suspected prostate cancer who underwent prostate biopsy. Total RNA was isolated from plasma, and TaqMan MicroRNA assays were used to analyze miR-145, miR-185, and miR-148 expression. First, differential miRNA expression among patient groups was evaluated. Then, miRNA levels were combined with clinical assessment outcomes, including results from invasive tests, using multivariate analysis to examine their ability in discriminating among the three patient groups. Our results suggest that miRNA is a promising molecular tool for clinical management of at-risk patients.

Role of miRNA-145, 148, and 185 and Stem Cells in Prostate Cancer

MicroRNAs (miRNAs) are small non-coding RNA molecules that play a role in cancer linked to the regulation of important cellular processes and pathways involving tumorigenesis, cell proliferation, differentiation, and apoptosis. A lot of human miRNA sequences have been identified which are linked to cancer pathogenesis. MicroRNAs, in prostate cancer (PC), play a relevant role as biomarkers, show a specific profile, and have been used as therapeutic targets. Prostate cancer (PC) is the most frequently diagnosed cancer in men. Clinical diagnoses among the gold standards for PC diagnosis and monitoring are prostate-specific antigen (PSA) testing, digital rectal examination, and prostate needle biopsies. PSA screening still has a large grey area of patients, which leads to overdiagnosis. Therefore, new biomarkers are needed to improve existing diagnostic tools. The miRNA expression profiles from tumour versus normal tissues are helpful and exhibit significant differences not only between cancerous and non-cancerous tissues, but also between different cancer types and subtypes. In this review, we focus on the role of miRNAs-145, 148, and 185 and their correlation with stem cells in prostate cancer pathogenesis. MiR-145, by modulating multiple oncogenes, regulates different cellular processes in PC, which are involved in the transition from localised to metastatic disease. MiR-148 is downregulated in high-grade tumours, suggesting that the miR-148-3 family might act as tumour suppressors in PC as a potential biomarker for detecting this disease. MiR-185 regulation is still unclear in being able to regulate tumour processes in PC. Nevertheless, other authors confirm the role of this miRNA as a tumour suppressor, suggesting its potential use as a suitable biomarker in disease prognosis. These three miRNAs are all involved in the regulation of prostate cancer stem cell behaviour (PCSCs). Within this contest, PCSCs are often involved in the onset of chemo-resistance in PC, therefore strategies for targeting this subset of cells are strongly required to control the disease. Hence, the relationship between these two players is interesting and important in prostate cancer pathogenesis and in PCSC stemness regulation, in the attempt to pave the way for novel therapeutic targets in prostate cancer.

Prognostic value of miR-21 for prostate cancer: a systematic review and meta-analysis

Elevated levels of miR-21 expression are associated with many cancers, suggesting it may be a promising clinical biomarker. In prostate cancer (PCa), however, there is still no consensus about the usefulness of miR-21 as an indicator of disease progression. This systematic review and meta-analysis was conducted to investigate the value of miR-21 expression as a prognostic measurement in PCa patients. Medline (Ovid), EMBASE, Web of Science, Scopus and Cochrane Library databases were systematically searched for relevant publications between 2010 to 2021. Studies exploring the relationship between miR-21 expression, PCa prognosis and clinicopathological factors were selected for review. Those reporting hazard ratio (HR) and 95% confidence intervals (CIs) were subject to meta-analyses. Fixed-effect models were employed to calculated pooled HRs and 95% CIs. Risk of bias in each study was assessed using QUIPS tool. Certainty of evidence in each meta-analysis was assessed using GRADE guidelines. A total of 64 studies were included in the systematic review. Of these, 11 were eligible for inclusion in meta-analysis. Meta-analyses revealed that high miR-21 expression was associated with poor prognosis: HR = 1.58 (95% CI = 1.19–2.09) for biochemical recurrence, MODERATE certainty; HR = 1.46 (95% CI = 1.06–2.01) for death, VERY LOW certainty; and HR = 1.26 (95% CI = 0.70–2.27) for disease progression, VERY LOW certainty. Qualitative summary revealed elevated miR-21 expression was significantly positively associated with PCa stage, Gleason score and risk groups. This systematic review and meta-analysis suggests that elevated levels of miR-21 are associated with poor prognosis in PCa patients. miR-21 expression may therefore be a useful prognostic biomarker in this disease.

High expression level of miR-1260 family in the peripheral blood of patients with ovarian carcinoma

The most common gynecologic cancers detected in women in Turkey are uterine cancer, ovarian cancer, and cervical cancer. These data reported that a mean of 3800 individuals were diagnosed with uterine cancer, 2790 were diagnosed with ovarian cancer, and 1950 were diagnosed with cervical cancer, and 400 individuals were diagnosed with other gynecologic cancers each year in Turkey. A mean of 14.270 individuals were detected to have been diagnosed with gynecologic cancers each year in the United States of America (USA). Ovarian cancer treatment is generally composed of chemotherapy, and surgery. In general, chemotherapy is administered after surgery. The identification of the molecular pathogenesis of ovarian cancer, and discovery of new moleculer biomarkers which facilitate the ovarian cancer treatment are required for an effective ovarian cancer treatment in clinics. miRNAs are reported to be the possible biologic indicators for various cancer types. We aimed to investigate 2 miRNAs which were suggested to have effect in ovarian cancer in our (previous) monozygotic twin study from miR-1260 microRNA family whose association with ovarian cancer yet has not been reported in the literature. We investigated the expression levels of miR-1260a, and miR-1260b miRNAs, in the peripheral blood lymphocytes of 150 familial and sporadic ovarian cancer patients, and of 100 healthy individuals of the control group who were matched for age, sex, and ethnicity with the patient group, and investigated their possible property of being a biologic indicator for ovarian cancer. The expression results of ovarian cancer patients were evaluated by comparison of the results of the control group in the study. The expression levels of miR-1260a, and miR-1260b in ovarian cancer patients were found highly increased compared with the levels in the control group. miR-1260a expression level in ovarian cancer patients was detected to have increased approximately 17 fold compared with the control group, and miR-1260b expression level in ovarian cancer patients was detected to have increased approximately 33 fold compared with the levels in the control group. The String Analyses showed that the miR-1260a was associated with the ribosomal protein family which was known to be effective in the translation stage of cell and that miR-1260b was associated with CHEK2 protein which was a member of the serine/threonine-protein kinase family. It should be investigated for larger cohorts in benign ovarian diseases and in different stages of patients receiving ovarian cancer treatment whether these two molecules are a noninvasive biomarker and therapeutic target to be used especially in the early diagnosis and prognosis of ovarian cancer in future.

Clinical Significance and Underlying Mechanisms of CELSR3 in Metastatic Prostate Cancer Based on Immunohistochemistry, Data Mining, and In Silico Analysis

Background: The treatment and survival rate of patients with metastatic prostate cancer (MPCa) remain unsatisfactory. Herein, the authors investigated the clinical value and potential mechanisms of cadherin EGF LAG seven-pass G-type receptor 3 (CELSR3) in MPCa to identify novel targets for clinical diagnosis and treatment. Materials and Methods: mRNA microarray and RNA-Seq (n = 1246 samples) data were utilized to estimate CELSR3 expression and to assess its differentiation ability in MPCa. Similar analyses were performed with miRNA-221-3p. Immunohistochemistry performed on clinical samples were used to evaluate the protein expression level of CELSR3 in MPCa. Based on CELSR3 differentially coexpressed genes (DCEGs), enrichment analysis was performed to investigate potential mechanisms of CELSR3 in MPCa. Results: The pooled standard mean difference (SMD) for CELSR3 was 0.80, demonstrating that CELSR3 expression was higher in MPCa than in localized prostate cancer (LPCa). CELSR3 showed moderate potential to distinguish MPCa from LPCa. CELSR3 protein expression was found to be markedly upregulated in MPCa than in LPCa tissues. The authors screened 894 CELSR3 DCEGs, which were notably enriched in the focal adhesion pathway. miRNA-221-3p showed a significantly negative correlation with CELSR3 in MPCa. Besides, miRNA-221-3p expression was downregulated in MPCa than in LPCa (SMD = -1.04), and miRNA-221-3p was moderately capable of distinguishing MPCa from LPCa. Conclusions: CELSR3 seems to play a pivotal role in MPCa by affecting the focal adhesion pathway and/or being targeted by miRNA-221-3p.

miR-425-5p as an exosomal biomarker for metastatic prostate cancer

Prostate cancer-related deaths are mostly caused by metastasis, which indicates the importance of identifying clinical prognostic biomarkers. In this study, we evaluated the expression profile of exosomal microRNAs (miRNAs) derived from metastatic prostate cancer (mPCa) cell lines (LNCaP and PC-3). miRNA signatures in exosomes and cells were evaluated by miRNA microarray analysis. Fourteen miRNAs were identified as candidates for specific noninvasive biomarkers. The expression of five miRNAs was validated using RT-qPCR, which confirmed that miR-205-5p, miR-148a-3p, miR-125b-5p, miR-183-5p, and miR-425-5p were differentially expressed in mPCa exosomes. Bioinformatic analyses showed that miR-425-5p was associated with residual tumor, pathologic T and N stages, and TP53 status in PCa samples. Gene ontology analysis of negatively correlated and predicted targeted genes showed enrichment of genes related to bone development pathways. The LinkedOmics database indicated that the potential target HSPB8 has a significant negative correlation with miR-425-5p. In conclusion, this study identified a panel of exosomal miRNAs with potential value as prognostic biomarkers for prostate cancer.

MiRNAs and radical prostatectomy: Current data, bioinformatic analysis and utility as predictors of tumour relapse

BACKGROUND

Studies of microRNAs (miRNAs) and genes have particular interest for cancer biology and medicine due to the discovery of new therapeutic targets and markers. These studies are extensively influenced by anticancer therapy, as miRNAs interfere with the therapy's efficacy in prostate cancer (PCa).

OBJECTIVES

In this article, we summarise the available data on the influence of radical prostatectomy (RP) and biochemical recurrence on miRNA expression.

MATERIALS AND METHODS

Molecular targets of these miRNAs, as well as the reciprocal relations between different miRNAs and their targets, were studied using the DIANA, STRING and TransmiR databases. Special attention was dedicated to the mechanisms of PCa development, miRNA, and associated genes as tumour development mediators.

RESULTS AND DISCUSSION

Combined analysis of the databases and available literature indicates that expression of four miRNAs that are associated with prostate cancer relapse and alter their expression after RP, combined with genes that closely interact with selected miRNAs, has high potential for the prediction of PCa relapse after RP. PCa tissues and biofluids, both immediately after RP for diagnostics/prognostics and in long-term (relapse) monitoring, may be used as sources of these miRNAs.

CONCLUSION

An overview of the usefulness of published data and bioinformatics resources looking for diagnostic markers and molecular targets is presented in this article. The selected miRNA and gene panels have good potential as prognostic and PCa relapse markers after RP and likely could also serve as markers for therapeutic efficiency on a broader scale.

Liquid Biopsy-Based Exo-oncomiRNAs Can Predict Prostate Cancer Aggressiveness

Liquid biopsy-based biomarkers, including microRNAs packaged within extracellular vesicles, are promising tools for patient management. The cytokine tumor necrosis factor-like weak inducer of apoptosis (TWEAK) is related to PCa progression and is found in the semen of patients with PCa. TWEAK can induce the transfer of exo-oncomiRNAs from tumor cells to body fluids, and this process might have utility in non-invasive PCa prognosis. We investigated TWEAK-regulated exo-microRNAs in semen and in post-digital rectal examination urine from patients with different degrees of PCa aggressiveness. We first identified 14 exo-oncomiRNAs regulated by TWEAK in PCa cells in vitro, and subsequently validated those using liquid biopsies from 97 patients with PCa. Exo-oncomiR-221-3p, -222-3p and -31-5p were significantly higher in the semen of high-risk patients than in low-risk peers, whereas exo-oncomiR-193-3p and -423-5p were significantly lower in paired samples of post-digital rectal examination urine. A panel of semen biomarkers comprising exo-oncomiR-221-3p, -222-3p and TWEAK was designed that could correctly classify 87.5% of patients with aggressive PCa, with 85.7% specificity and 76.9% sensitivity with an area under the curve of 0.857. We additionally found that TWEAK modulated two exo-oncomiR-221-3p targets, TCF12 and NLK. Overall, we show that liquid biopsy detection of TWEAK-regulated exo-oncomiRNAs can improve PCa prognosis prediction.

Identification of a Transcriptomic Prognostic Signature by Machine Learning Using a Combination of Small Cohorts of Prostate Cancer

Determining which treatment to provide to men with prostate cancer (PCa) is a major challenge for clinicians. Currently, the clinical risk-stratification for PCa is based on clinico-pathological variables such as Gleason grade, stage and prostate specific antigen (PSA) levels. But transcriptomic data have the potential to enable the development of more precise approaches to predict evolution of the disease. However, high quality RNA sequencing (RNA-seq) datasets along with clinical data with long follow-up allowing discovery of biochemical recurrence (BCR) biomarkers are small and rare. In this study, we propose a machine learning approach that is robust to batch effect and enables the discovery of highly predictive signatures despite using small datasets. Gene expression data were extracted from three RNA-Seq datasets cumulating a total of 171 PCa patients. Data were re-analyzed using a unique pipeline to ensure uniformity. Using a machine learning approach, a total of 14 classifiers were tested with various parameters to identify the best model and gene signature to predict BCR. Using a random forest model, we have identified a signature composed of only three genes (JUN, HES4, PPDPF) predicting BCR with better accuracy [74.2%, balanced error rate (BER) = 27%] than the clinico-pathological variables (69.2%, BER = 32%) currently in use to predict PCa evolution. This score is in the range of the studies that predicted BCR in single-cohort with a higher number of patients. We showed that it is possible to merge and analyze different small and heterogeneous datasets altogether to obtain a better signature than if they were analyzed individually, thus reducing the need for very large cohorts. This study demonstrates the feasibility to regroup different small datasets in one larger to identify a predictive genomic signature that would benefit PCa patients.

Omics Derived Biomarkers and Novel Drug Targets for Improved Intervention in Advanced Prostate Cancer

Prostate cancer (PCa) is one of the most frequently diagnosed malignancies, and the fifth leading cause of cancer related mortality in men. For advanced PCa, radical prostatectomy, radiotherapy, and/or long-term androgen deprivation therapy are the recommended treatment options. However, subsequent progression to metastatic disease after initial therapy results in low 5-year survival rates (29%). Omics technologies enable the acquisition of high-resolution large datasets that can provide insights into molecular mechanisms underlying PCa pathology. For the purpose of this article, a systematic literature search was conducted through the Web of Science Database to critically evaluate recent omics-driven studies that were performed towards: (a) Biomarker development and (b) characterization of novel molecular-based therapeutic targets. The results indicate that multiple omics-based biomarkers with prognostic and predictive value have been validated in the context of PCa, with several of those being also available for commercial use. At the same time, omics-driven potential drug targets have been investigated in pre-clinical settings and even in clinical trials, holding the promise for improved clinical management of advanced PCa, as part of personalized medicine pipelines.

MiR-93/miR-375: Diagnostic Potential, Aggressiveness Correlation and Common Target Genes in Prostate Cancer

Dysregulation of miRNAs has a fundamental role in the initiation, development and progression of prostate cancer (PCa). The potential of miRNA in gene therapy and diagnostic applications is well documented. To further improve miRNAs' ability to distinguish between PCa and benign prostatic hyperplasia (BPH) patients, nine miRNA (-21, -27b, -93, -141, -205, -221, -182, -375 and let-7a) with the highest reported differentiation power were chosen and for the first time used in comparative studies of serum and prostate tissue samples. Spearman correlations and response operating characteristic (ROC) analyses were applied to assess the capability of the miRNAs present in serum to discriminate between PCa and BPH patients. The present study clearly demonstrates that miR-93 and miR-375 could be taken into consideration as single blood-based non-invasive molecules to distinguish PCa from BPH patients. We indicate that these two miRNAs have six common, PCa-related, target genes (CCND2, MAP3K2, MXI1, PAFAH1B1, YOD1, ZFYVE26) that share the molecular function of protein binding (GO:0005515 term). A high diagnostic value of the new serum derived miR-182 (AUC = 0.881, 95% confidence interval, CI = 0.816-0.946, p < 0.0001, sensitivity and specificity were 85% and 79%, respectively) is also described.

Comparative analysis of epi-miRNA expression levels in local/locally advanced and metastatic prostate cancer patients

Abnormal expression of enzymes involved in epigenetic mechanisms, such as DNA methyl transferases, can trigger large chaos in cellular gene expression networks and eventually lead to cancer progression. In our study, which is a pioneer in the literature that clinicopathologically evaluates the expression of 30 epi-miRNAs in prostate cancer (PCa), we investigated which of the new miRNA class epi-miRNAs could be an effective biomarker in the diagnosis and progression of PCa. In this study, the expression levels of 30 epi-miRNAs in whole blood samples from 25 control, 25 PCa and 40 metastatic PCa patients were investigated by the Quantitative Real-Time PCR method. Then, promoter methylation levels of 11 epi-miRNAs, whose expression levels were found to be significantly higher, were examined by methylation-specific qPCR method. The correlations between miRNA expression levels and clinicopathological parameters (Gleason Score (GS), PSA levels, TNM Staging) in different stages of PCa groups as well as disease-specific expression levels were examined. We found a hypomethylation in the promoter regions of miRNAs that showed a direct proportional increase with PSA levels (miR-34b/c, miR-148a, miR-152), GS's (miR-34a-5p, miR-34b/c, miR-101-2, miR-126, miR-148a, miR- 152, miR-185-5p) and T staging (miR-34a-5p, miR-34b/c, miR-101-2, miR-126, miR-140, miR-148a, miR-152, miR-185-5p) (p < 0.05). When miR-200a/b was evaluated according to clinicopathological parameters, it acted as an onco-miR in local/local advanced PCa and as a tumor-suppressor-miR in metastatic stage. This study is novel in the sense that our findings draw attention to the important role of miRNAs as diagnostic and prognostic biomarkers in PCa.

Validation of the four-miRNA biomarker panel MiCaP for prediction of long-term prostate cancer outcome

Improved prostate cancer prognostic biomarkers are urgently needed. We previously identified the four-miRNA prognostic biomarker panel MiCaP ((miR-23a-3p × miR-10b-5p)/(miR-133a-3p × miR-374b-5p)) for prediction of biochemical recurrence (BCR) after radical prostatectomy (RP). Here, we identified an optimal numerical cut-off for MiCaP dichotomisation using a training cohort of 475 RP patients and tested this in an independent cohort of 281 RP patients (PCA281). Kaplan–Meier, uni- and multivariate Cox regression analyses were conducted for multiple endpoints: BCR, metastatic-(mPC) and castration-resistant prostate cancer (CRPC), prostate cancer-specific (PCSS) and overall survival (OS). Functional effects of the four MiCaP miRNAs were assessed by overexpression and inhibition experiments in prostate cancer cell lines. We found the numerical value 5.709 optimal for MiCaP dichotomisation. This was independently validated in PCA281, where a high MiCaP score significantly [and independent of the Cancer of the Prostate Risk Assessment Postsurgical (CAPRA-S) score] predicted BCR, progression to mPC and CRPC, and PCSS, but not OS. Harrell’s C-index increased upon addition of MiCaP to CAPRA-S for all endpoints. Inhibition of miR-23a-3p and miR-10b-5p, and overexpression of miR-133a-3p and miR-374b-5p significantly reduced cell survival. Our results may promote future implementation of a MiCaP-based test for improved prostate cancer risk stratification.

A health disparities study of MicroRNA-146a expression in prostate cancer samples derived from African American and European American patients

Considering the prevalence of prostate cancer all over the world, it is desired to have tools, technologies, and biomarkers which help in early detection of the disease and discriminate different races and ethnic groups. Genetic information from the single gene analysis and genome-wide association studies have identified few biomarkers, however, the drivers of prostate cancer remain unknown in the majority of prostate cancer patients. In those cases where genetic association has been identified, the genes confer only a modest risk of this cancer, hence, making them less relevant for risk counseling and disease management. There is a need for additional biomarkers for diagnosis and prognosis of prostate cancer. MicroRNAs are a class of non-protein coding RNA molecules that are frequently dysregulated in different cancers including prostate cancer and show promise as diagnostic biomarkers and targets for therapy. Here we describe the role of micro RNA 146a (miR-146a) which may serve as a diagnostic and prognostic marker for prostate cancer, as indicated from the data presented in this report. Also, a pilot study indicated differential expression of miR-146a in prostate cancer cell lines and tissues from different racial groups. Reduced expression of miR-146a was observed in African American tumor tissues compared to those from European Whites This report provides a novel insight into understanding the prostate carcinogenesis.

Seminal plasma microRNAs improve diagnosis/prognosis of prostate cancer in men with moderately altered prostate-specific antigen

There is an urgent need for accurate non-invasive biomarkers for prostate cancer (PCa) diagnosis and disease risk stratification. Previous data suggests that total seminal plasma (SP) represents a source of miRNAs for screening. We have evaluated a panel of eight PCa-associated miRNAs for their potential use as PCa biomarkers in SP by analyzing their levels using RT-qPCR. Multivariate logistic regression modelling and clinical risk assessment were performed for those SP miRNAs statistically altered between PCa and non-PCa (HCt and/or BPH) groups. Our results provide evidence that altered miRNA expression in PCa tissue can also be detected in total SP. We obtained a clinically useful SP miRNA-based combined model (PSA+miR-142-3p+miR-223-3p+miR-93-5p), which improves PCa specificity of the PSA test, for, firstly, predicting the presence of malignant tumors in a sample from the total population and secondly, and more interestingly for clinicians, for predicting PCa in samples from the positive PSA screening test (PSA>4 ng/ml). Additionally, [PSA+miR-30d-5p+miR-93-5p] and [PSA+miR-30d-5p] models have been shown to be useful for predicting the disease aggressiveness with diagnostic accuracy. In conclusion, our results provide evidence that miRNAs in total SP represent a useful target for evaluation for PCa, which technically simplifies the future use of semen miRNA-based models as non-invasive biomarkers to increase the efficiency of PCa diagnosis and prognosis.

Challenges in Cancer Biomarker Discovery Exemplified by the Identification of Diagnostic MicroRNAs in Prostate Tissues

Identification and clinical translation of routinely tested biomarkers require a complex and multistep workflow. Here, we described a confirmatory process estimating the utility of previously identified candidate tissue miRNAs for diagnosis of prostate cancer (PCa). RNA was isolated from formalin-fixed paraffin-embedded (FFPE) prostate tissue surgically resected from 44 patients with PCa and 24 patients with benign prostate hyperplasia (BPH). Of the 92 RNA samples obtained, 68 represented 42 malignant (PCa) areas and 26 represented nonmalignant (PCa 0%) areas of the prostate tissue sections. The levels of miR-32-5p, miR-183-5p, miR-141-5p, miR-187-3p, miR-375, miR-663b, miR-615-3p, miR-205-5p, miR-221-3p, and miR-222-3p were evaluated using Exiqon chemistry. Five (miR-32-5p, miR-141-5p, miR-187-3p, miR-375, and miR-615-3p), one (miR-32-5p), and two (miR-32-5p and miR-141-5p) miRNAs discriminated between BPH and areas of cancer-bearing prostate tissue harboring different numbers of cancer cells (PCa 15–70%, PCa 2–10%, and PCA 0%, respectively), with an area under the receiver operating characteristics curve (AUC-ROC) > 0.9. Only miRNA 32-5p discriminated BPH specimens from sections of cancer-bearing prostate tissue with a low percentage, a high percentage, or no dysplastic cells. miR-32-5p could be considered as potential diagnostic biomarker discriminating BPH from noncancerous areas within cancer-bearing prostate tissue. However, further clinical studies are warranted to confirm its diagnostic utility.

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.

The Panel of 12 Cell-Free MicroRNAs as Potential Biomarkers in Prostate Neoplasms

Prostate cancer is a global biological, medical, and social issue aggravated by the lack of reliable, highly specific, and sensitive non-invasive tests for diagnosis and staging of prostate cancer. One prospective source of biomarkers are the cell-free miRNAs present in various biological fluids. In the present study, we validated the diagnostic potential of cell-free miRNAs: miR-19b, miR-22, miR-92a, miR-378, miR-425, miR-30e, miR-31, miR-125b, miR-200b, miR-205, miR-375, and miR-660; we estimated the required sample size and the minimal miRNA set for a subsequent large-scale validation study. Relative expression of 12 miRNA combined in 31 ratios was investigated in three fractions of biological fluids (urine extracellular vesicles, clarified urine, and plasma) obtained from patients with prostate cancer (n = 10), benign prostate hyperplasia (n = 8), and healthy volunteers (n = 11). Eight of the miRNAs found in urine vesicles (miR-19b, miR-30e, miR-31, miR-92a, miR-125, miR-200, miR-205, and miR-660) showed great promise and when combined into six ratios (miR-125b/miR-30e, miR-200/miR-30e, miR-205/miR-30e, miR-31/miR-30e, miR-660/miR-30e, and miR-19b/miR-92a) could classify patients with prostate cancer, benign prostate hyperplasia, and healthy donors with 100% specificity, 100% sensitivity, and with a high degree of reliability for most donors.

Training and validation of a novel 4-miRNA ratio model (MiCaP) for prediction of postoperative outcome in prostate cancer patients

Background

New molecular biomarkers for prostate cancer (PC) prognosis are urgently needed. Ratio-based models are attractive, as they require no additional normalization. Here, we train and independently validate a novel 4-miRNA prognostic ratio model for PC.

Patients and methods

By genome-wide miRNA expression profiling of PC tissue samples from 123 men who underwent radical prostatectomy (RP) (PCA123, training cohort), we identified six top candidate prognostic miRNAs and systematically tested their ability to predict postoperative biochemical recurrence (BCR). The best miRNA-based prognostic ratio model (MiCaP) was validated in two independent cohorts (PCA352 and PCA476) including >800 RP patients in total. Clinical end points were BCR and prostate cancer-specific survival (CSS). The prognostic potential of MiCaP was assessed by univariate and multivariate Cox-regression analyses and Kaplan-Meier analyses.

Results

We identified a 4-miRNA ratio model, MiCaP (miR-23a-3p×miR-10b-5p)/(miR-133a×miR-374b-5p), that predicted time to BCR independently of routine clinicopathologic variables in the training cohort (PCA123) and was successfully validated in two independent RP cohorts. In addition, MiCaP was a significant predictor of CSS in univariate analysis [HR 3.35 (95% CI 1.34 - 8.35), P = 0.0096] and in multivariate analysis [HR 2.43 (95% CI 1.45-4.07), P = 0.0210]. As proof-of-principle, we also analyzed MiCaP in plasma samples from 111 RP patients. A high MiCaP score in plasma was significantly associated with BCR (P = 0.0036, Kaplan-Meier analysis). Limitations include low mortality rates (CSS: 5.4%).

Conclusions

We identified a novel 4-miRNA ratio model (MiCaP) with significant independent prognostic value in three RP cohorts, indicating promising potential to improve PC risk stratification.

Molecular Biomarkers in Localized Prostate Cancer: ASCO Guideline

PURPOSE

This guideline provides recommendations for available tissue-based prostate cancer biomarkers geared toward patient selection for active surveillance, identification of clinically significant disease, choice of postprostatectomy adjuvant versus salvage radiotherapy, and to address emerging questions such as the relative value of tissue biomarkers compared with magnetic resonance imaging.

METHODS

An ASCO multidisciplinary Expert Panel, with representatives from the European Association of Urology, American Urological Association, and the College of American Pathologists, conducted a systematic literature review of localized prostate cancer biomarker studies between January 2013 and January 2019. Numerous tissue-based molecular biomarkers were evaluated for their prognostic capabilities and potential for improving management decisions. Here, the Panel makes recommendations regarding the clinical use and indications of these biomarkers.

RESULTS

Of 555 studies identified, 77 were selected for inclusion plus 32 additional references selected by the Expert Panel. Few biomarkers had rigorous testing involving multiple cohorts and only 5 of these tests are commercially available currently: Oncotype Dx Prostate, Prolaris, Decipher, Decipher PORTOS, and ProMark. With various degrees of value and validation, multiple biomarkers have been shown to refine risk stratification and can be considered for select men to improve management decisions. There is a paucity of prospective studies assessing short- and long-term outcomes of patients when these markers are integrated into clinical decision making.

RECOMMENDATIONS

Tissue-based molecular biomarkers (evaluating the sample with the highest volume of the highest Gleason pattern) may improve risk stratification when added to standard clinical parameters, but the Expert Panel endorses their use only in situations in which the assay results, when considered as a whole with routine clinical factors, are likely to affect a clinical decision. These assays are not recommended for routine use as they have not been prospectively tested or shown to improve long-term outcomes-for example, quality of life, need for treatment, or survival. Additional information is available at www.asco.org/genitourinary-cancer-guidelines.

A Novel Predictor Tool of Biochemical Recurrence after Radical Prostatectomy Based on a Five-MicroRNA Tissue Signature

Within five to ten years after radical prostatectomy (RP), approximately 15–34% of prostate cancer (PCa) patients experience biochemical recurrence (BCR), which is defined as recurrence of serum levels of prostate-specific antigen >0.2 µg/L, indicating probable cancer recurrence. Models using clinicopathological variables for predicting this risk for patients lack accuracy. There is hope that new molecular biomarkers, like microRNAs (miRNAs), could be potential candidates to improve risk prediction. Therefore, we evaluated the BCR prognostic capability of 20 miRNAs, which were selected by a systematic literature review. MiRNA expressions were measured in formalin-fixed, paraffin-embedded (FFPE) tissue RP samples of 206 PCa patients by RT-qPCR. Univariate and multivariate Cox regression analyses were performed, to assess the independent prognostic potential of miRNAs. Internal validation was performed, using bootstrapping and the split-sample method. Five miRNAs (miR-30c-5p/31-5p/141-3p/148a-3p/miR-221-3p) were finally validated as independent prognostic biomarkers. Their prognostic ability and accuracy were evaluated using C-statistics of the obtained prognostic indices in the Cox regression, time-dependent receiver-operating characteristics, and decision curve analyses. Models of miRNAs, combined with relevant clinicopathological factors, were built. The five-miRNA-panel outperformed clinically established BCR scoring systems, while their combination significantly improved predictive power, based on clinicopathological factors alone. We conclude that this miRNA-based-predictor panel will be worth to be including in future studies.

Circulating miRNAs as Diagnostic and Prognostic Biomarkers in Common Solid Tumors: Focus on Lung, Breast, Prostate Cancers, and Osteosarcoma

An early cancer diagnosis is essential to treat and manage patients, but it is difficult to achieve this goal due to the still too low specificity and sensitivity of classical methods (imaging, actual biomarkers), together with the high invasiveness of tissue biopsies. The discovery of novel, reliable, and easily collectable cancer markers is a topic of interest, with human biofluids, especially blood, as important sources of minimal invasive biomarkers such as circulating microRNAs (miRNAs), the most promising. MiRNAs are small non-coding RNAs and known epigenetic modulators of gene expression, with specific roles in cancer development/progression, which are next to be implemented in the clinical routine as biomarkers for early diagnosis and the efficient monitoring of tumor progression and treatment response. Unfortunately, several issues regarding their validation process are still to be resolved. In this review, updated findings specifically focused on the clinical relevance of circulating miRNAs as prognostic and diagnostic biomarkers for the most prevalent cancer types (breast, lung, and prostate cancers in adults, and osteosarcoma in children) are described. In addition, deep analysis of pre-analytical, analytical, and post-analytical issues still affecting the circulation of miRNAs' validation process and routine implementation is included.

Circular RNA profile identifies circOSBPL10 as an oncogenic factor and prognostic marker in gastric cancer

The prognosis after curative resection of gastric cancer (GC) remains unsatisfactory, and thus, the development of treatments involving alternative molecular and genetic targets is critical. Circular RNAs (circRNAs), which are newly discovered molecules with key roles in the non-coding RNA network, have been identified as critical regulators in various cancers. Here, we aimed to determine the circRNA expression profile and to investigate the functional and prognostic significance of circRNA in GC. Using next-generation sequencing profiling, we first characterized an abundant circRNA in GC, hsa_circ_0008549, derived from the OSBPL10 gene and named it circOSBPL10. The expression of circOSBPL10 was found to be upregulated in GC tissues by quantitative RT-PCR, and silencing of circOSBPL10 significantly inhibited GC cell growth, migration, and invasion in multiple experiments. We further confirmed that miR-136-5p is a downstream target of circOSBPL10 using RNA pull-down and luciferase reporter assays. Rescue experiments confirmed that circOSBPL10 regulates biological functions in GC cells via a circOSBPL10-miR-136-5p-WNT2 axis. In vivo experiments showed that circOSBPL10 promotes tumor growth and metastasis in mice. Furthermore, the level of circOSBPL10 was observed to be a prognostic marker of the overall survival and disease-free survival of patients with GC. Taken together, our findings reveal that circOSBPL10 may serve as a new proliferation factor and prognostic marker in GC.

Semen miRNAs Contained in Exosomes as Non-Invasive Biomarkers for Prostate Cancer Diagnosis

Although it is specific for prostatic tissue, serum prostate-specific antigen (PSA) screening has resulted in an over-diagnosis of prostate cancer (PCa) and many unnecessary biopsies of benign disease due to a well-documented low cancer specificity, thus improvement is required. We profiled the expression level of miRNAs contained in semen exosomes from men with moderately increased PSA levels to assess their usefulness, either alone or in addition to PSA marker, as non-invasive biomarkers, for the early efficient diagnosis and prognosis of PCa. An altered miRNA expression pattern was found by a high throughput profiling analysis in PCa when compared with healthy individuals (HCt) exosomal semen samples. The presence of vasectomy was taken into account for the interpretation of results. Fourteen miRNAs were selected for miRNA validation as PCa biomarkers in a subsequent set of semen samples. In this explorative study, we describe miRNA-based models, which included miRNA expression values together with PSA levels, that increased the classification function of the PSA screening test with diagnostic and/or prognostic potential: [PSA + miR-142-3p + miR-142-5p + miR-223-3p] model (AUC:0,821) to discriminate PCa from BPH (Sn:91,7% Sp:42,9% vs Sn:100% Sp:14,3%); and [PSA + miR-342-3p + miR-374b-5p] model (AUC: 0,891) to discriminate between GS ≥ 7 tumours and men presenting PSA ≥ 4 ng/ml with no cancer or GS6 tumours (Sn:81,8% Sp:95% vs Sn:54,5% Sp:90%). The pathway analysis of predicted miRNA target genes supports a role for these miRNAs in PCa aetiology and/or progression. Our study shows semen exosome miRNA-based models as molecular biomarkers with the potential to improve PCa diagnosis/prognosis efficiency. As the next step, further prospective studies on larger cohorts of patients are required to validate the diagnostic and/or prognostic role of the miRNA panel before it could be adopted into clinical practice.

Predictive factors for response to salvage stereotactic body radiotherapy in oligorecurrent prostate cancer limited to lymph nodes: a single institution experience

Background

In patients presenting with limited nodal recurrence following radical prostatectomy (RP), stereotactic body radiotherapy (SBRT) results might improve with a better case selection.

Methods

Single-institution retrospective analysis of patients presenting with 1–3 lymph node (LN) recurrences (N1 or M1a) on 18F-Choline PET/CT. Prior therapy included radical prostatectomy (RP) ± salvage radiotherapy (RT), in absence of any systemic therapy.

Outcome parameters were biochemical response (BR), time to biochemical recurrence (TBR) and time interval between SBRT and androgen deprivation therapy start (TADT). Time to event endpoints was analysed using Kaplan-Meier method. Potential prognostic factors were examined using univariate proportional hazards regression for TADT and logistic regression for BR. The optimal cut-off point for LN size was calculated using the Contal and O’Quigley method.

Results

25 patients fulfilling study criteria were treated with SBRT from January 2010 to January 2015 and retrospectively analysed. Median follow up was 18 months and median LN diameter 10.5 mm. SBRT was delivered to a median dose of 36 Gy in three fractions (range: 30–45 Gy). BR was reached in 52% of cases. Median TBR was 11.9 months and significantly longer in patients with larger LN (Hazard ratio [HR] = 0.87, P = 0.03). Using 14 mm as cut off for LN, median TBR was 10.8 months for patients with small LN (18 patients), and 21.2 months for patients with large LN (6 patients) (P unadjusted = 0.009; P adjusted = 0.099). ADT was started in 32% of patients after a median follow-up of 18 months.

Conclusions

For PCa patients with 1–3 LN recurrence after RP (± salvage RT), SBRT might result in a better biochemical control when delivered to larger sized (≥ 14 mm) LN metastases. This study is hypothesis generating and results should be tested in a larger prospective trial.

Electronic supplementary material

The online version of this article (10.1186/s12894-019-0515-z) contains supplementary material, which is available to authorized users.

A novel combined miRNA and methylation marker panel (miMe) for prediction of prostate cancer outcome after radical prostatectomy

Improved prognostic biomarkers are needed to guide personalized prostate cancer (PC) treatment decisions. Due to the prominent molecular heterogeneity of PC, multimarker panels may be more robust. Here, 25 selected top-candidate miRNA and methylation markers for PC were profiled by qPCR in malignant radical prostatectomy (RP) tissue specimens from 198 PC patients (Cohort 1, training). Using GLMnet, we trained a novel multimarker model (miMe) comprising nine miRNAs and three methylation markers that predicted postoperative biochemical recurrence (BCR) independently of the established clinicopathological CAPRA-S nomogram in Cox multivariate regression analysis in Cohort 1 (HR [95% CI]: 1.53 [1.26-1.84], p < 0.001). This result was successfully validated in two independent RP cohorts (Cohort 2, n = 159: HR [95% CI]: 1.35 [1.06-1.73], p = 0.015. TCGA, n = 350: HR [95% CI]: 1.34 [1.01-1.77], p = 0.04). Notably, in CAPRA-S low-risk patients, a high miMe score was associated with >6 times higher risk of BCR, suggesting that miMe may help identify PC patients at high risk of progression despite favorable clinicopathological factors postsurgery. Finally, miMe was a significant predictor of cancer-specific survival (p = 0.019, log-rank test) in a merged analysis of 357 RP patients. In conclusion, we trained, tested and validated a novel 12-marker panel (miMe) that showed significant independent prognostic value in three RP cohorts. In the future, combining miMe score with existing clinical nomograms may improve PC risk stratification and thus help guide treatment decisions.

The previously uncharacterized lncRNA APP promotes prostate cancer progression by acting as a competing endogenous RNA

Long noncoding RNAs (lncRNAs) promote cell proliferation, migration, invasion and castration resistance in prostate cancer (PCa). Understanding the inherited molecular mechanisms by which lncRNAs contribute to the progression of PCa to a lethal disease could have an important impact on cancer detection, diagnosis and prognosis. In our study, PCa-associated lncRNA transcripts from RNA-seq data were identified and screened via bioinformatics analysis, NCBI annotations and literature review. We identified a novel lncRNA, lncAPP (lncRNA activated in PCa progression), which activates in PCa progression and is expressed in primary tumor tissues and urine samples of patients with localized or advanced PCa. Urinary-based lncAPP is a promising biomarker for predicting PCa progression. In vitro and in vivo studies demonstrated that lncAPP enhanced cell proliferation and promoted migration and invasion. The underlying mechanism of lncRNA was investigated by RNA immunoprecipitation, dual-luciferase reporter system assay, etc. Upregulation of lncAPP promoted cell migration and invasion via competitively binding miR218 to facilitate ZEB2/CDH2 expression. In addition, in vivo subcutaneous tumor xenograft models and tail intravenously injection metastatic models were constructed to evaluate lncRNA function. Targeting lncAPP/miR218 axis in cell lines and tumor xenografts restrained tumor progression properties both in vitro and in vivo. These results establish that lncAPP/miR218 axis plays a critical role in PCa progression, and they also suggest new strategies to prevent tumor progression for therapeutic purposes.

Diagnostic biomarker and therapeutic target applications of miR-326 in cancers: A systematic review

MicroRNAs (miRNAs) are endogenous mediators of RNA interference and have key roles in the modulation of gene expression under healthy, inflamed, stimulated, carcinogenic, or other cells, and tissues of a pathological state. Many studies have proved the association between miRNAs and cancer. The role of miR-326 as a tumor suppressor miRNA in much human cancer confirmed. We will explain the history and the role of miRNAs changes, especially miR-326 in cancers and other pathological conditions. Attuned with these facts, this review highlights recent preclinical and clinical research performed on miRNAs as novel promising diagnostic biomarkers of patients at early stages, prediction of prognosis, and monitoring of the patients in response to treatment. All related publications retrieved from the PubMed database, with keywords such as epigenetic, miRNA, microRNA, miR-326, cancer, diagnostic biomarker, and therapeutic target similar terms from 1899 to 2018 with limitations in the English language. Recently, researchers have focused on the impacts of miRNAs and their association in inflammatory, autoinflammatory, and cancerous conditions. Recent studies have suggested a major pathogenic role in cancers and autoinflammatory diseases. Investigations have explained the role of miRNAs in cancers, autoimmunity, and autoinflammatory diseases, and so on. The miRNA-326 expression has an important role in cancer conditions and other diseases.

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

Improved biomarkers for prostate cancer (PC) risk stratification are urgently needed. Here, we aimed to develop a novel multimarker model for prediction of biochemical recurrence (BCR) after curatively intended radical prostatectomy (RP), based on minimally invasive sampling of blood and urine. We initially measured the levels of 45 selected miRNAs by RT-qPCR in exosome enriched cell-free urine samples collected prior to RP from 215 PC patients (Cohort 1, training). We trained a novel logistic regression model (pCaP), comprising five urine miRNAs (miR-151a-5p, miR-204-5p, miR-222-3p, miR-23b-3p and miR-331-3p) and serum prostate-specific antigen (PSA), which significantly predicted time to BCR in Cohort 1 (univariate Cox regression analysis: HR = 3.12, p < 0.001). Next, using the same exact numeric cutoff for dichotomization as trained in Cohort 1, we tested and successfully validated the prognostic potential of pCaP in two additional cohorts, including 199 (Cohort 2, HR = 2.24, p = 0.002) and 205 (Cohort 3, HR = 2.15, p = 0.004) RP patients, respectively. pCaP remained a significant predictor of BCR, also after adjustment for pathological T-stage, surgical margin status and Gleason grade group (p < 0.05 in multivariate Cox regression analysis: HR = 2.72, 1.94 and 1.83 for Cohorts 1, 2 and 3, respectively). Additionally, pCaP scores correlated positively with the established clinical risk stratification nomogram CAPRA in all three PC cohorts (Pearson's rho: 0.45, 0.39 and 0.44). Together, our results suggest that the minimally invasive pCaP model could potentially be used in the future to improve PC risk stratification and to guide more personalized treatment decisions. Further clinical validation studies are warranted.

Assessment of miR-98-5p, miR-152-3p, miR-326 and miR-4289 Expression as Biomarker for Prostate Cancer Diagnosis

Prostate cancer (PCa) is one of the most commonly diagnosed cancers worldwide, accounting for almost 1 in 5 new cancer diagnoses in the US alone. The current non-invasive biomarker prostate specific antigen (PSA) has lately been presented with many limitations, such as low specificity and often associated with over-diagnosis. The dysregulation of miRNAs in cancer has been widely reported and it has often been shown to be specific, sensitive and stable, suggesting miRNAs could be a potential specific biomarker for the disease. Previously, we identified four miRNAs that are significantly upregulated in plasma from PCa patients when compared to healthy controls: miR-98-5p, miR-152-3p, miR-326 and miR-4289. This panel showed high specificity and sensitivity in detecting PCa (area under the curve (AUC) = 0.88). To investigate the specificity of these miRNAs as biomarkers for PCa, we undertook an in depth analysis on these miRNAs in cancer from the existing literature and data. Additionally, we explored their prognostic value found in the literature when available. Most studies showed these miRNAs are downregulated in cancer and this is often associated with cancer progression and poorer overall survival rate. These results suggest our four miRNA signatures could potentially become a specific PCa diagnostic tool of which prognostic potential should also be explored.

Independent Validation of a Diagnostic Noninvasive 3-MicroRNA Ratio Model (uCaP) for Prostate Cancer in Cell-Free Urine

BACKGROUND

Detection of prostate cancer (PC) based on serum prostate-specific antigen (PSA) testing leads to many unnecessary prostate biopsies, overdiagnosis, and overtreatment of clinically insignificant tumors. Thus, novel and more accurate molecular biomarkers are required.

METHODS

Using reverse transcription quantitative PCR, we measured the concentrations of 45 preselected microRNAs (miRNAs) in extracellular vesicle-enriched cell-free urine samples from 4 independent patient cohorts from Spain and Denmark, including 758 patients with clinically localized PC, 289 noncancer controls with benign prostatic hyperplasia (BPH), and 233 patients undergoing initial transrectal ultrasound (TRUS)-guided prostate biopsy owing to PC suspicion (101 with benign and 132 with malignant outcome). Diagnostic potential was assessed by ROC and decision curve analysis.

RESULTS

We identified and successfully validated 8 upregulated and 21 downregulated miRNAs in urine from PC patients. Furthermore, we validated a previously identified 3-miRNA diagnostic ratio model, uCaP (miR-222-3p*miR-24-3p/miR-30c-5p). High uCaP scores were distinctive of PC in urine samples from BPH vs PC patients in 3 independent cohorts [area under the curve (AUC) = 0.84, 0.71, 0.72]. Additionally, uCaP predicted TRUS biopsy results with greater accuracy than PSA (AUC uCaP = 0.644; AUC PSA = 0.527) for patients within the diagnostic gray zone (PSA ≤ 10 ng/mL).

CONCLUSIONS

We successfully validated a urine-based diagnostic 3-miRNA signature for PC (uCaP) in 3 independent patient cohorts from 2 countries. In the future, the simple and noninvasive uCaP test may be used to help more accurately select patients for prostate biopsy. Prospective clinical validation is warranted.

Anabolic Androgenic Steroids: Searching New Molecular Biomarkers

Even if anabolic androgenic steroid (AAS) abuse is clearly associated with a wide spectrum of collateral effects, adolescents and athletes frequently use a large group of synthetic derivatives of testosterone, both for aesthetic uses and for improving performance. Over the last few years, the development of MicroRNA (miRNA) technologies has become an essential part of research projects and their role as potential molecular biomarkers is being investigated by the scientific community. The circulating miRNAs detection as a diagnostic or prognostic tool for the diagnosis and treatment of several diseases is very useful, because with a minimal quantity of sample (peripheral blood), miRNAs are very sensitive. Even more, miRNAs remain stable both at room temperature and during freeze-thaw cycles. These characteristics highlight the important role of miRNAs in the near future as new tools for anti-doping. The article provides a systematic review and meta-analysis on the role of miRNAs as new potential molecular biomarkers of AAS use/abuse. Particularly, this paper analyzed the “miRNA signature” use as biomarkers for health disorders, focusing on the organ damages which are related to ASS use/abuse. Moreover, this review aims to provide a future prospect for less invasive or non-invasive procedures for the detection of circulating miRNA biomarkers as doping assumption signaling.

Expression patterns and bioinformatic analysis of miR-1260a and miR-1274a in Prostate Cancer Tunisian patients

Currently, microRNAs (miRs) represent great biomarkers in cancer due to their stability and their potential role in diagnosis, prognosis and therapy. This study aims to evaluate the expression levels of miRs-1260 and -1274a in prostate cancer (PC) samples and to identify their eventual targets by using bioinformatic analysis. In this project, we evaluated the expression status of miRs-1260 and -1274a in 86 PC patients and 19 controls by using real-time quantitative PCR and 2^-ΔΔCt method. Moreover, we retrieved validated and predicted targets of miRs from several datasets by using the "multiMir" R/Bioconductor package. We have found that miRs-1260 and -1274a were over-expressed in PC patients compared to controls (p < 1 × 10^-5). Moreover ROC curve for miRs-1260 and 1274a showed a good performance to distinguish between controls group and PC samples with an area under the ROC curve of 0.897 and 0.784 respectively. However, no significant association could be shown between these two miRs and clinical parameters such as PSA levels, Gleason score, tumor stage, D'Amico classification, lymph node metastasis statues, tumor recurrence, metastasis status and progression after a minimum of 5 years follow-up. Finally, a bioinformatic analysis revealed the association between these two miRs and several targets implicated in prostate cancer initiation pathways.

The MicroRNA-326: Autoimmune diseases, diagnostic biomarker, and therapeutic target

MicroRNAs (miRNAs) are uniquely regulated in healthy, inflamed, activated, cancerous, or other cells and tissues of a pathological state. Many studies confirm that immune dysregulation and autoimmune diseases with inflammation are correlated with various miRNA expression changes in targeted tissues and cells in innate or adaptive immunity. In this review, we will explain the history and classification of epigenetic changes. Next, we will describe the role of miRNAs changes, especially mir-326 in autoimmunity, autoinflammatory, and other pathological conditions. A systematic search of MEDLINE, Embase, and Cochrane Library was presented for all related studies from 1899 to 2017 with restrictions in the English language. In recent years, researchers have concentrated on mostly those roles of miRNA that are correlated with the inflammatory and anti-inflammatory process. Latest studies have proposed a fundamental pathogenic role in cancers and autoinflammatory diseases. Studies have described the role of microRNAs in autoimmunity and autoinflammatory diseases, cancers, and so on. The miRNA-326 expression plays a significant role in autoimmune and other types of diseases.