miR-19, miR-345, miR-519c-5p serum levels predict adverse pathology in prostate cancer patients eligible for active surveillance

Epigenetics as a Key Factor in Prostate Cancer

Nowadays, prostate cancer is one of the most common forms of malignant neoplasms in men all over the world. Against the background of increasing incidence, there is a high mortality rate from prostate cancer, which is associated with an inadequate treatment strategy. Such a high prevalence of prostate cancer requires the development of methods that can ensure early detection of the disease, improve the effectiveness of treatment, and predict the therapeutic effect. Under these circumstances, it becomes crucial to focus on the development of effective diagnostic and therapeutic approaches. Due to the development of molecular genetic methods, a large number of studies have been accumulated on the role of epigenetic regulation of gene activity in cancer development, since it is epigenetic changes that can be detected at the earliest stages of cancer development. The presence of epigenetic aberrations in tumor tissue and correlations with drug resistance suggest new therapeutic approaches. Detection of epigenetic alterations such as CpG island methylation, histone modification, and microRNAs as biomarkers will improve the diagnosis of the disease, and the use of these strategies as targets for therapy will allow for greater personalization of prostate cancer treatment.

Prostate-derived circulating microRNAs add prognostic value to prostate cancer risk calculators

Prostate cancer is the second leading cause of malignancy-related deaths among American men. Active surveillance is a safe option for many men with less aggressive disease, yet definitively determining low-risk cancer is challenging with biopsy alone. Herein, we sought to identify prostate-derived microRNAs in patient sera and serum extracellular vesicles, and determine if those microRNAs improve upon the current clinical risk calculators for prostate cancer prognosis before and after biopsy. Prostate-derived intracellular and extracellular vesicle-contained microRNAs were identified by small RNA sequencing of prostate cancer patient explants and primary cells. Abundant microRNAs were included in a custom microRNA PCR panel that was queried in whole serum and serum extracellular vesicles from a diverse cohort of men diagnosed with prostate cancer. The levels of these circulating microRNAs significantly differed between indolent and aggressive disease and improved the area under the curve for pretreatment nomograms of prostate cancer disease risk. The microRNAs within the extracellular vesicles were the most informative and improved the AUC to 0.739 compared to the existing nomogram alone, which has an AUC of 0.561. The microRNAs in the whole serum improved it to AUC 0.675. In summary, quantifying microRNAs circulating in extracellular vesicles is a clinically feasible assay that may provide additional information for assessing prostate cancer risk stratification.

Prostate-derived circulating microRNAs add prognostic value to prostate cancer risk calculators

Prostate cancer is the second leading cause of malignancy-related deaths among American men. Active surveillance is a safe option for many men with less aggressive disease, yet definitively determining low-risk cancer is challenging with biopsy alone. Herein, we sought to identify prostate-derived microRNAs in patient sera and serum extracellular vesicles, and determine if those microRNAs improve upon the current clinical risk calculators for prostate cancer prognosis before and after biopsy. Prostate-derived intracellular and extracellular vesicle-contained microRNAs were identified by small RNA sequencing of prostate cancer patient explants and primary cells. Abundant microRNAs were included in a custom microRNA PCR panel that was queried in whole serum and serum extracellular vesicles from a diverse cohort of men diagnosed with prostate cancer. The levels of these circulating microRNAs significantly differed between indolent and aggressive disease and improved the area under the curve for pretreatment nomograms of prostate cancer disease risk. The microRNAs within the extracellular vesicles had improved prognostic value compared to the microRNAs in the whole serum. In summary, quantifying microRNAs circulating in extracellular vesicles is a clinically feasible assay that may provide additional information for assessing prostate cancer risk stratification.

Salivary miR-31-5p, miR-345-3p, and miR-424-3p Are Reliable Biomarkers in Patients with Oral Squamous Cell Carcinoma

If not detected early, oral squamous cell carcinoma (OSCC) has very poor prognosis, emphasizing the need for reliable early diagnostics. Saliva is considered a promising surrogate biosample for OSCC detection, because it comes into contact with many cells of the tumor mass, providing a comprehensive sampling of tumor-specific biomolecules. Although several protein- and RNA-based salivary biomarkers have been proposed for the detection of OSCC, the results of the studies show large differences. Our goal was to clarify which salivary microRNAs (miRNA) show reliably high expression in the saliva of OSCC patients, to be used as cancer-specific biomarkers, and potentially as early diagnostic biomarkers. Based on a detailed literature search, we selected six miRNAs commonly overexpressed in OSCC, and analyzed their expression in saliva samples of cancer patients and controls by real-time quantitative PCR. Our results suggest that miR-345 and miR-31-5p are consistently upregulated salivary biomarkers for OSCC, and a three-miRNA panel of miR-345, miR-31-5p, and miR-424-3p can distinguish cancer and control patients with high sensitivity.

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.

Prediction of Grade Reclassification of Prostate Cancer Patients on Active Surveillance through the Combination of a Three-miRNA Signature and Selected Clinical Variables

Simple Summary

Active surveillance (AS) has evolved as an alternative to radical treatment for potentially indolent prostate cancer. However, current selection criteria for entering AS are suboptimal, and a significant percentage of patients discontinue AS because of disease reclassification. Hence, there is an unmet need for novel biomarkers for the accurate identification of high-risk PCa and the unequivocal classification of indolent disease. Circulating biomarkers, including microRNAs identified through liquid biopsies, represent a valuable approach to improve on currently available clinicopathological risk-stratification tools. In an attempt to identify specific microRNA signatures as potential circulating biomarkers, the authors performed an unprecedented analysis of the global microRNA profile in plasma samples from AS patients and identified and validated a three-microRNA signature able to predict patient reclassification. The addition of the three-microRNA signature was able to improve the performance of currently available clinicopathological variables, thus showing potential for the refinement of AS patients’ selection.

Abstract

Active surveillance (AS) has evolved as a strategy alternative to radical treatments for very low risk and low-risk prostate cancer (PCa). However, current criteria for selecting AS patients are still suboptimal. Here, we performed an unprecedented analysis of the circulating miRNome to investigate whether specific miRNAs associated with disease reclassification can provide risk refinement to standard clinicopathological features for improving patient selection. The global miRNA expression profiles were assessed in plasma samples prospectively collected at baseline from 386 patients on AS included in three independent mono-institutional cohorts (training, testing and validation sets). A three-miRNA signature (miR-511-5p, miR-598-3p and miR-199a-5p) was found to predict reclassification in all patient cohorts (training set: AUC 0.74, 95% CI 0.60–0.87, testing set: AUC 0.65, 95% CI 0.51–0.80, validation set: AUC 0.68, 95% CI 0.56–0.80). Importantly, the addition of the three-miRNA signature improved the performance of the clinical model including clinicopathological variables only (AUC 0.70, 95% CI 0.61–0.78 vs. 0.76, 95% CI 0.68–0.84). Overall, we trained, tested and validated a three-miRNA signature which, combined with selected clinicopathological variables, may represent a promising biomarker to improve on currently available clinicopathological risk stratification tools for a better selection of truly indolent PCa patients suitable for AS.

The effectiveness of plasma miR-33a-5p as a predictive biomarker for the efficacy of colorectal cancer chemotherapy

Several chemotherapeutic options are available for patients with metastatic colorectal cancer (mCRC), making it important to individualize treatment regimens. Individualization requires the clinical application of biomarkers for regimen selection, which is presently insufficient. miRNAs serve an important role in the control of biological processes in several types of cancer, acting as plasma biomarkers. The current study aimed to evaluate novel plasma microRNAs for predicting chemo-resistance in chemotherapy for patients with colorectal cancer (CRC) by employing a Toray 3D-Gene microRNA array-based approach, which compared plasma content before and during treatment. Specific miRNAs that acted as biomarkers of the fluoropyrimidine (FP) + oxaliplatin (OX) + bevacizumab (BEV) regime, a common first-line treatment for mCRC, were searched. The plasma samples of 110 patients with mCRC who had received the FP+OX+BEV regimen were subjected to microarray analyses using the 3D-Gene miRNA microarray platform, after which miRNAs levels were quantified via reverse transcription- quantitative PCR. Patients exhibiting complete response, partial response (PR) and reduced stable disease (SD) were defined as responders. Patients with extended SD and progression disease (PD) were defined as non-responders. Following microarray analysis, miR-33a-5p was selected as the candidate miRNA as it was upregulated in non-responder plasma samples. The expression of miR-33a-5p was upregulated in the non-responders (n=15) compared with the responders (n=95) (P=0.032). The high expression group demonstrated significantly poor progression-free survival (P<0.01). To evaluate whether miR-33a-5p can serve as a marker of chemo-resistance, miR-33a-5p expression levels were assessed at the following three time-points: Pre-point (before chemotherapy); PR-point (3-months after chemotherapy began); and PD-point (the time at which recurrence or progression was recorded). The results revealed that expression levels were significantly increased at the PD-point when compared with that at the pre-point (P=0.024). The current study determined that the miR-33a-5p expression level in the plasma may serve as a predictive marker of efficacy and as a biomarker of chemo-resistance.

miR-345-3p serves a protective role during gestational diabetes mellitus by targeting BAK1

Recent studies have demonstrated that microRNAs (miRs) serve a crucial role during the development of gestational diabetes mellitus (GDM). However, the mechanisms underlying miR-345-3p and its protective role during GDM have not been previously reported. The present study investigated miR-345-3p expression and function in vitro, and the possible molecular mechanisms underlying GDM. Compared with healthy pregnant women, miR-345-3p was downregulated in the placental tissue and peripheral blood of patients with GDM. Further investigation revealed that BCL2-antagonist/killer 1 (BAK1) was a predicted target gene of miR-345-3p, and the expression of BAK1 was significantly increased in patients with GDM compared with healthy pregnant women. In vitro analysis revealed that miR-345-3p mimic significantly increased cell viability, migration and invasion, inhibited apoptosis, upregulated Bcl-2 and matrix metallopeptidase 9 expression, and decreased Bax expression compared with the control group. Furthermore, miR-245-3p mimic-induced alterations were reversed by BAK1 overexpression. The results suggested that miR-345-3p overexpression exhibited a protective role in patients with GDM by inhibiting HTR8-/SVneo cell apoptosis, and promoting cell proliferation and migration via targeting BAK1. The use of miR-345-3p for the diagnosis of GDM requires further investigation.

MicroRNA-92a Targets SERTAD3 and Regulates the Growth, Invasion, and Migration of Prostate Cancer Cells via the P53 Pathway

Background

The miR-17-92 cluster, consisting of six mature miRNAs including miR-17, miR-18a, miR-19a, miR-19b, miR-20a, and miR-92a, plays a key role in the tumorigenesis and development of various cancers. The dysregulation of the cluster correlates with the biological mechanism of tumor growth and metastasis in vivo. However, the relationship between miR-17-92 cluster and malignancy of prostate cancer remains unclear, and its regulatory mechanism is worth investigating for controlling the proliferation and invasion of prostate cancer.

Materials and Methods

The expressions of miR-17-92 cluster members were measured using real-time quantitative RT-PCR. WB and real-time quantitative RT-PCR were used to detect the expression of SERTAD3, p38, p21, p53 protein levels and transcription levels. Cell proliferation and apoptosis were evaluated using cell proliferation assay, EdU and Hoechst assay, colony formation experiment and flow cytometry analyses. Cell migration and invasion were determined via transwell assays. The TargetScan, miRDB, starBase databases and luciferase reporter assays were used to confirm the target gene of miR-92a.

Results

The relative expression of miR-92a was threefold higher in the metastatic PC-3 cells compared with the non-metastatic LNCaP cells. Down-regulation of miR-92a in PC-3 cells led to the inhibition of cell proliferation, migration, and invasion, while its overexpression in LNCaP cells resulted in the promotion of cell proliferation, migration, and invasion. The role of SERTAD3 in prostate cancer can be alleviated by miR-92a inhibitor.

Conclusion

SERTAD3 was the direct target gene of miR-92a in prostate cancer cells; inhibition of SERTAD3-dependent miR-92a alleviated the growth, invasion, and migration of prostate cancer cells by regulating the expression of the key genes of the p53 pathway, including p38, p53 and p21. These results suggested that targeting SERTAD3 by the induction of overexpression of miR-92a may be a treatment option in prostate cancer.

A Tetra-Panel of Serum Circulating miRNAs for the Diagnosis of the Four Most Prevalent Tumor Types

The purpose of this study is to clinically validate a series of circulating miRNAs that distinguish between the 4 most prevalent tumor types (lung cancer (LC); breast cancer (BC); colorectal cancer (CRC); and prostate cancer (PCa)) and healthy donors (HDs). A total of 18 miRNAs and 3 housekeeping miRNA genes were evaluated by qRT-PCR on RNA extracted from serum of cancer patients, 44 LC, 45 BC, 27 CRC, and 40 PCa, and on 45 HDs. The cancer detection performance of the miRNA expression levels was evaluated by studying the area under the curve (AUC) of receiver operating characteristic (ROC) curves at univariate and multivariate levels. miR-21 was significantly overexpressed in all cancer types compared with HDs, with accuracy of 67.5% (p = 0.001) for all 4 tumor types and of 80.8% (p < 0.0001) when PCa cases were removed from the analysis. For each tumor type, a panel of miRNAs was defined that provided cancer-detection accuracies of 91%, 94%, 89%, and 77%, respectively. In conclusion, we have described a series of circulating miRNAs that define different tumor types with a very high diagnostic performance. These panels of miRNAs would constitute the basis of different approaches of cancer-detection systems for which clinical utility should be validated in prospective cohorts.

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.

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.

Functional roles and potential clinical application of miRNA-345-5p in prostate cancer

BACKGROUND

MicroRNAs (miRNAs) are small non-coding RNAs, which negatively regulate gene expression and impact prostate cancer (PCa) growth and progression. Circulating miRNAs are stable and detectable in cell-free body fluids, such as serum. Investigation of circulating miRNAs presents great potential in uncovering new insights into the roles of miRNAs in PCa diagnosis and therapy.

METHODS

Using TaqMan miRNA quantitative reverse transcription polymerase chain reaction (RT-qPCR), we compared the expression levels of five miRNAs (miR-193a-3p, miR-9-3p, miR-335-5p, miR-330-3p, and miR-345-5p) in serum samples from 20 normal individuals without cancer, 25 patients with localized disease, 25 patients with hormone-naïve or hormone sensitive metastatic disease, and 25 patients with metastatic castration-resistant prostate cancer (CRPC). These five miRNAs were identified as potential oncogenes in our previous studies. MiR-345-5p was further investigated for its functional roles in CRPC cells.

RESULTS

We discovered that miR-9-3p, miR-330-3p-3p, and miR-345-5p were significantly overexpressed in serum from PCa patients when compared to serum from individuals without cancer. No differential expression patterns were observed between different disease categories. However, patients who were in remission after androgen deprivation therapy (ADT) appeared to have significantly lower miR-345-5p levels compared to the rest of the groups. We further demonstrated that miR-345-5p promotes CRPC cell growth and migration in vitro and validated that CDKN1A (the gene encoding p21) is the direct target of miR-345-5p.

CONCLUSIONS

Our results set the stage for a further investigation on the potential application of circulating miR-345-5p as a biomarker for PCa diagnosis and therapeutic response. The oncogenic roles of miR-345-5p through targeting CDKN1A render it a potential therapeutic target for PCa.

Long noncoding RNA n339260 promotes vasculogenic mimicry and cancer stem cell development in hepatocellular carcinoma

Vasculogenic mimicry (VM) refers to the unique capability of aggressive tumor cells to mimic the pattern of embryonic vasculogenic networks. Cancer stem cells (CSC) represent a subpopulation of tumor cells endowed with the capacity for self‐renewal and multilineage differentiation. Previous studies have indicated that CSC may participate in the formation of VM. With the advance of high‐resolution microarrays and massively parallel sequencing technology, long noncoding RNAs (lncRNAs) are suggested to play a critical role in tumorigenesis and, in particular, the development of human hepatocellular carcinoma (HCC). Currently, no definitive relationship between lncRNA and VM formation has been described. In the current study, we demonstrated that expression of the lncRNA, n339260, is associated with CSC phenotype in HCC, and n339260 level correlated with VM, metastasis, and shorter survival time in an animal model. Overexpression of n339260 in HepG2 cells was associated with a significant increase in CSC. Additionally, the appearance of VM and vascular endothelial (VE)‐cadherin, a molecular marker of VM, was also induced by n339260 overexpression. Using a short hairpin RNA approach, n339260 was silenced in tumor cells, and knockdown of n339260 was associated with reduced VM and CSC. The results of this study indicate that n339260 promotes VM, possibly by the development of CSC. The related molecular pathways may be used as novel therapeutic targets for the inhibition of HCC angiogenesis and metastasis.

Correlation between body mass index (BMI) and the Gleason score of prostate biopsies in Chinese population

We assessed the correlation between BMI and Gleason score in prostate biopsies in Chinese Population. In this retrospective study, we collected the Gleason score, PSA, BMI, age, race, and other related clinical data on 290 patients who had undergone prostatic biopsy. We then compared the prostate cancer detection rates and Gleason scores between the high BMI group (BMI ≥ 25; 143 cases) and low BMI group (< 25; 147 cases). Among the 137 patients in whom prostate cancer detected, 70 had high BMIs and 67 had normal BMIs, making the detection rates 48.95% and 45.58% respectively. Seventeen prostate cancer patients had low Gleason scores (Gleason score < 7), while 120 had high Gleason scores (≥ 7). Within the high BMI group, 44.76% had high Gleason scores, which was significantly greater than the 38.10% in the low BMI group (P = 0.027). These results indicate that while there was no effect of BMI on the rate of positive prostate cancer biopsies, the rate of high Gleason scores was greater in the high BMI group than the normal BMI group.

Hiding in Plain Sight: Rediscovering the Importance of Noncoding RNA in Human Malignancy

At the time of its construction in the 1950s, the central dogma of molecular biology was a useful model that represented the current state of knowledge for the flow of genetic information after a period of prolific scientific discovery. Unknowingly, it also biased many of our assumptions going forward. Whether intentional or not, genomic elements not fitting into this paradigm were deemed unimportant and emphasis on the study of protein-coding genes prevailed for decades. The phrase "Junk DNA," first popularized in the 1960s, is still used with alarming frequency to describe the entirety of noncoding DNA. It has since become apparent that RNA molecules not coding for protein are vitally important in both normal development and human malignancy. Cancer researchers have been pioneers in determining noncoding RNA function and developing new technologies to study these molecules. In this review, we will discuss well known and newly emerging species of noncoding RNAs, their functions in cancer, and new technologies being utilized to understand their mechanisms of action in cancer. Cancer Res; 78(9); 2149-58. ©2018 AACR.

Circulating serum microRNA-345 correlates with unfavorable pathological response to preoperative chemoradiotherapy in locally advanced rectal cancer

Preoperative chemoradiotherapy (pre-CRT) has been represented as the standard treatment for locally advanced rectal cancer (LARC), but large variations of tumor radiation response to CRT have been reported in the clinic. To explore the function of microRNAs as potential therapeutic predictors of pre-CRT pathological response in LARC, we analyzed global miRNA expression in CRT-sensitive and CRT-resistant groups before treatment. MiR-345 was significantly elevated in the CRT-resistant group. Therefore, miR-345 was selected as a candidate for further analysis. We assessed the correlation between the miRNA signatures and the chemoradiotherapeutic response in 20 randomly selected LARC tissue samples (Validation set) and 87 serum samples (Training set) by qRT-PCR. Further, we validated the results in 42 randomly selected LARC serum samples (Validation set). High miR-345 expression was significantly correlated with unfavorable pre-CRT pathological response in tissue and serum. Moreover, low miR-345 levels predicted superior 3-year local recurrence free survival (LRFS). Taken together, circulating serum miR-345 correlates with unfavorable pre-CRT response and poor locoregional control in LARC. It might be a promising biomarker to facilitate patient stratification for personalized treatment.

miR-19-5p Enhances Tumorigenesis in Human Colorectal Cancer Cells by Targeting TSPYL5

The cancer suppressor gene, testis-specific protein Y-encoded-like 5 (TSPYL5), has been implicated in various cancers, including colorectal cancer (CRC). In this study, we investigated the role of TSPYL5 in the development of CRC in vitro. First, we used bioinformatics to predict the binding target of TSPYL5, and found that the microRNA, miR-19-5p, bound to the 3' untranslated region (UTR) of TSPYL5. This interaction was further validated by the dual-luciferase assay. Second, we found that overexpressed TSPYL5 enhanced apoptosis in HT29 cells and reduced cell proliferation, reduced cell migration/invasion, and most of the cells accumulated in the G0/G1 phase of the cell cycle. These effects were reversed after addition of miR-19-5p mimics. Third, knocking down expression of miR-19-5p also increased apoptosis, and reduced cell proliferation, migration, and invasion in HT29 cells. We speculate that miR-19-5p induces the degradation of TSPYL5 by binding to its 3'UTR. Our results suggest that increasing the expression of TSPYL5 in HT29 cells or inhibiting miR-19-5p promotes apoptosis of HT29 cells. Thus, miR-19-5p could be used as biomarkers of CRC, with potential implications for diagnosis and therapeutic intervention.

MicroRNA-19a acts as a prognostic marker and promotes prostate cancer progression via inhibiting VPS37A expression

Prostate cancer (PCa) is a leading cause of cancer-related deaths among males worldwide. However, the molecular mechanisms underlying the progression of PCa remain unclear. Despite several reported miRNAs in prostate cancer, these reports lacked system-level identification of differentially expressed miRNAs in large sample size. Moreover, it's still largely unknown how miRNAs result in tumorigenesis and progression of PCa. Therefore, by analyzing three public databases, we identified 16 upregulated miRNAs and 13 downregulated miRNAs, and validated miR-19a was one of the most upregulated miRNAs using qRT-PCR. The dual-luciferase reporter assays indicated VPS37A was a potential target of miR-19a. Functional assays revealed miR-19a served as an oncogene by inhibiting VPS37A. Notably, a significant inverse correlation of miR-19a and VPS37A expression was observed in PCa specimens. Moreover, miR-19a-high and VPS37A-low phenotypes were associated with poor prognosis with biochemical recurrence-free probability. In this study, we confirmed the oncogenic role of miR-19a via targeting VPS37A in PCa, identifying miR-19a and VPS37A as diagnosis and therapeutic biomarkers for PCa.

Combinations of elevated tissue miRNA-17-92 cluster expression and serum prostate-specific antigen as potential diagnostic biomarkers for prostate cancer

The aim of the present study was to investigate the effectiveness of the miR-17-92 cluster as a disease progression marker in prostate cancer (PCa). Reverse transcription-quantitative polymerase chain reaction analysis was used to detect the microRNA (miR)-17-92 cluster expression levels in tissues from patients with PCa or benign prostatic hyperplasia (BPH), in addition to in PCa and BPH cell lines. Spearman correlation was used for comparison and estimation of correlations between miRNA expression levels and clinicopathological characteristics such as the Gleason score and prostate-specific antigen (PSA). Receiver operating curve (ROC) analysis was performed for evaluation of specificity and sensitivity of miR-17-92 cluster expression levels for discriminating patients with PCa from patients with BPH. Kaplan-Meier analysis was plotted to investigate the predictive potential of miR-17-92 cluster for PCa biochemical recurrence. Expression of the majority of miRNAs in the miR-17-92 cluster was identified to be significantly increased in PCa tissues and cell lines. Bivariate correlation analysis indicated that the high expression of unregulated miRNAs was positively correlated with Gleason grade, but had no significant association with PSA. ROC curves demonstrated that high expression of miR-17-92 cluster predicted a higher diagnostic accuracy compared with PSA. Improved discriminating quotients were observed when combinations of unregulated miRNAs with PSA were used. Survival analysis confirmed a high combined miRNA score of miR-17-92 cluster was associated with shorter biochemical recurrence interval. miR-17-92 cluster could be a potential diagnostic and prognostic biomarker for PCa, and the combination of the miR-17-92 cluster and serum PSA may enhance the accuracy for diagnosis of PCa.

Targeting MicroRNAs in Prostate Cancer Radiotherapy

Radiotherapy is one of the most important treatment options for localized early-stage or advanced-stage prostate cancer (CaP). Radioresistance (relapse after radiotherapy) is a major challenge for the current radiotherapy. There is great interest in investigating mechanisms of radioresistance and developing novel treatment strategies to overcome radioresistance. MicroRNAs (miRNAs) are small, non-coding RNAs that regulate gene expression at the post-transcriptional level, participating in numerous physiological and pathological processes including cancer invasion, progression, metastasis and therapeutic resistance. Emerging evidence indicates that miRNAs play a critical role in the modulation of key cellular pathways that mediate response to radiation, influencing the radiosensitivity of the cancer cells through interplaying with other biological processes such as cell cycle checkpoints, apoptosis, autophagy, epithelial-mesenchymal transition and cancer stem cells. Here, we summarize several important miRNAs in CaP radiation response and then discuss the regulation of the major signalling pathways and biological processes by miRNAs in CaP radiotherapy. Finally, we emphasize on microRNAs as potential predictive biomarkers and/or therapeutic targets to improve CaP radiosensitivity.

Comparison of microRNA profiles between benign and malignant salivary gland tumors in tissue, blood and saliva samples: a prospective, case-control study

Introduction

Salivary gland tumors (SGTs) are rare head and neck malignancies consisting of a spectrum of tumors with different biological behaviors.

Objective

In this study we aimed to find out differential expression of microRNA profiles between benign and malignant SGTs.

Methods

We investigated the possible role of 95 microRNAs in the 20 patients with salivary gland tumors with comparison of 17 patients without malignancy or salivary gland diseases. Sixteen of the tumors were benign (seven pleomorphic adenomas, nine Warthin tumors), four of them were malignant (two squamous cell carcinomas, one high grade mucoepidermoid carcinoma, one adenocarcinoma). Serum and saliva samples were collected from both patients and control group. Tissue samples of tumor masses were also collected from patient group.

Results

Among studied microRNAs miR-21, miR-23a, miR-27a, miR-223, miR-125b, miR-126, miR-146a, miR-30e were down regulated in the benign group compared to control group in the serum samples (p-values are 0.04, 0.00005, 0.00005, 0.0022, 0.031, 0.00008, 0.044, and 0.0007, respectively). When tissue samples were studied miR-21, miR-31, miR-199a-5p, miR-146b, miR-345 were up-regulated in the malignant group compared to benign group (p values are 0.006, 0.02, 0.013, 0.013, 0.041, respectively). miR-30e showed statistically significant up-regulation in malignant tumor group's plasma samples compared to benign group (p = 0.034). There was no statistically significant difference in saliva samples between groups.

Conclusion

Our results showed that different microRNAs may play role in salivary tumor pathogenesis according to biological behavior. Although there was no difference in saliva samples between groups, according to tissue and serum samples miR-21 and 30e may have an important role; since they were down-regulated in benign tumors whereas up-regulated in malignant ones.

Exosomal and Non-Exosomal Urinary miRNAs in Prostate Cancer Detection and Prognosis

BACKGROUND

MicroRNAs (miRNAs) are non-coding small RNAs, involved in post-transcriptional regulation of many target genes.

METHODS

Five miRNAs that have been consistently found deregulated in PCa (miR-21, miR-141, miR-214, miR-375, and let-7c) were analyzed in urinary pellets from 60 prostate cancer (PCa) patients and 10 healthy subjects by qRT-PCR. Besides, urinary exosomes were isolated by differential centrifugation and analyzed for those miRNAs.

RESULTS

Significant upregulation of miR-21, miR-141, and miR-375 was found comparing PCa patients with healthy subjects in urinary pellets, while miR-214 was found significantly downregulated. Regarding urinary exosomes, miR-21 and miR-375 were also significantly upregulated in PCa but no differences were found for miR-141. Significant differences were found for let-7c in PCa in urinary exosomes while no differences were observed in urinary pellets. A panel combining miR-21 and miR-375 is suggested as the best combination to distinguish PCa patients and healthy subjects, with an AUC of 0.872. Furthermore, the association of miRNAs with clinicopathological characteristics was investigated. MiR-141 resulted significantly correlated with Gleason score in urinary pellets and let-7c with clinical stage in urinary exosomes. Additionally, miR-21, miR-141, and miR-214 were found significantly deregulated in intermediate/high-risk PCa versus low-risk/healthy subjects in urinary pellets. Significant differences between both groups were found in urinary exosomes for miR-21, miR-375, and let-7c.

CONCLUSIONS

These findings suggest that the analysis of miRNAs-especially miRNA-21 and miR-375- in urine could be useful as biomarkers in PCa. Prostate 77: 573-583, 2017. © 2016 Wiley Periodicals, Inc.

MiR-199a-3p suppresses proliferation and invasion of prostate cancer cells by targeting Smad1

OBJECTIVES

This study was intended to analyze effects of miR-199a-3p and Smad1 on proliferation, migration and invasion of prostate cancer (PCa) cells.

RESULTS

MiR-199a-3p was significantly decreased in PCa tissues in comparison to that in adjacent normal tissues (P < 0.05). Over-expressed miR-199a-3p markedly suppressed proliferation and invasion of PCa cells (P < 0.05). MiR-199a-3p was negatively correlated with Smad1 expression, and overexpression of Smad1 could antagonize the effects of miR-199a-3p on PCa cells.

MATERIALS AND METHODS

The PCa tissues and their adjacent normal tissues were collected from 54 PCa patients. Expressions of miR-199a-3p and Smad1 mRNA in tissues and cells were evaluated with real-time quantitative polymerase chain reaction (RT-qPCR), and immunohistochemistry assay was used to detect Smad1 protein expressions. The target relationship between miR-199a-3p and Smad1 was assessed by luciferase reporter assay. The PCa cell lines (i.e. PC-3 cells) were transfected with miR-199a-3p mimics and Smad1-cDNA. MTT and Transwell assays were applied to detect proliferative, migratory and invasive abilities of PCa cells.

CONCLUSIONS

MiR-199a-3p suppressed proliferation and invasion of PCa cells by targeting Smad1.

miRNAs associated with prostate cancer risk and progression

Prostate cancer is the most common malignancy among men in the US. Though considerable improvement in the diagnosis of prostate cancer has been achieved in the past decade, predicting disease outcome remains a major clinical challenge. Recent expression profiling studies in prostate cancer suggest microRNAs (miRNAs) may serve as potential biomarkers for prostate cancer risk and disease progression. miRNAs comprise a large family of about 22-nucleotide-long non-protein coding RNAs, regulate gene expression post-transcriptionally and participate in the regulation of numerous cellular processes. In this review, we discuss the current status of miRNA in studies evaluating the disease progression of prostate cancer. The discussion highlights key findings from previous studies, which reported the role of miRNAs in risk and progression of prostate cancer, providing an understanding of the influence of miRNA on prostate cancer. Our review indicates that somewhat consistent results exist between these studies and reports on several prostate cancer related miRNAs. Present promising candidates are miR-1, −21, 106b, 141, −145, −205, −221, and −375, which are the most frequently studied and seem to be the most promising for diagnosis and prognosis for prostate cancer. Nevertheless, the findings from previous studies suggest miRNAs may play an important role in the risk and progression of prostate cancer as promising biomarkers.

Profiling of a panel of radioresistant prostate cancer cells identifies deregulation of key miRNAs

Background

miRNAs are increasingly associated with the aggressive phenotype of prostate tumours. Their ability to control radiobiologically-relevant cellular processes strengthens their potential as novel markers of response to radiation therapy.

Purpose

To identify miRNAs associated with increased clonogenic survival following radiation exposure.

Material and methods

The miRNA expression profiles of a panel of 22RV1 cells with varying levels of radiosensitivities (hypoxic H-22Rv1 cells, RR-22Rv1 cells derived from WT-22Rv1 cells through 2-Gy fractionated repeated exposure, the associated aged matched cells (AMC-22Rv1) and the WT-22Rv1 cell lines) were generated and cross-analysed to identify common miRNAs associated with a radioresistant phenotype.

Results

Increased clonogenic survival following irradiation was associated with significant modifications in miRNA expression pattern. miR-221 (up) and miR-4284 (down) in RR-22Rv1 and MiR-31 and miR-200c in AMC-22Rv1 were the most uniquely significantly deregulated miRNAs when compared to WT-22Rv1 cells. miR-200c ranked as the most downregulated miRNAs in hypoxic, when compared to RR-22Rv1 cells. miR-200a was the only differentially expressed miRNA between RR-22Rv1 and AMC-22Rv1 cells. miR-210 yielded the highest fold change in expression in H-22Rv1, when compared to WT-22RV1 cells.

Conclusion

This study identifies candidate miRNAs for the development of novel prognostic biomarkers for radiotherapy prostate cancer patients.

miRNAs as novel biomarkers in the management of prostate cancer

microRNAs (miRNAs) are small non-coding RNAs that control gene expression posttranscriptionally and are part of the giant non codifying genoma. Cumulating data suggest that miRNAs are promising potential biomarkers for many diseases, including cancer. Prostate cancer (PCa) detection is currently based in the serum prostate-specific antigen biomarker and digital rectal examination. However, these methods are limited by a low predictive value and the adverse consequences associated with overdiagnosis and overtreatment. New biomarkers that could be used for PCa detection and prognosis are still needed. Recent studies have demonstrated that aberrant expressions of microRNAs are associated with the underlying mechanisms of PCa. This review attempts to extensively summarize the current knowledge of miRNA expression patterns, as well as their targets and involvement in PCa pathogenesis. We focused our review in the value of circulating and urine miRNAs as biomarkers in PCa patients, highlighting the existing discrepancies between different studies, probably associated with the important methodological issues related to their quantitation and normalization. The majority of studies have been performed in serum or plasma, but urine obtained after prostate massage appears as a new way to explore the usefulness of miRNAs. Large screening studies to select a miRNA profile have been completed, but bioinformatics tools appear as a new approach to select miRNAs that are relevant in PCa development. Promising preliminary results were published concerning miR-141, miR-375 and miR-21, but larger and prospective studies using standardized methodology are necessary to define the value of miRNAs in the detection and prognosis of PCa.

Evidence and potential in vivo functions for biofluid miRNAs: From expression profiling to functional testing: Potential roles of extracellular miRNAs as indicators of physiological change and as agents of intercellular information exchange

A controversial hypothesis in RNA biology is that extracellular microRNAs (miRNAs), including those in biofluids, have non-cell-autonomous activities. Several studies have characterized biofluid miRNA profiles in healthy or diseased individuals but generally have failed to identify distinct disease signatures. It remains unclear whether alterations in fluid miRNA levels are simply indicators of physiological change or whether miRNAs are taken up by new cells at concentrations sufficient to affect gene expression. There are limitations to biofluid miRNA studies performed to date: methodology for isolating and quantifying biofluid miRNAs is not standardized across studies; mechanistic details of miRNA release and uptake are incomplete; and efforts to assess non-cell-autonomous effects of extracellular miRNAs have employed predominantly in vitro strategies. We describe controversies and questions that need to be addressed to test possible in vivo roles of extracellular miRNAs and propose model organisms with rich genetic toolkits for carrying out in vivo functional analyses.

[Oncological principles for local control of primary tumor]

OBJECTIVE

Review of the databases of carcinogenesis and the principles of local control of the primary tumor in order to decrease the risk of tumor progression and predict metastatic behavior.

MATERIALS AND METHODS

Review of the literature using Medline databases based on scientific relevance. Research was centered on the characteristics of solid tumor development, the basics of local control of the primary tumor, latest advance in genomics and the oncological principles applied on prostate cancer surgery.

RESULTS

The cornerstone in order to cure a local or locally advanced cancer is to eradicate the primary tumor. This should be done using effective methods that can assure local control, decrease the risk of progression and metastasis. The oncological surgery is the most important step in order to have this tumor control, beside radiotherapy and systemic therapy associated. In localized prostate cancer, surgery remains the gold standard between the multiple therapeutic modalities proposed.

CONCLUSION

The local control of solid malignant tumor is primordial in order to change the natural history of the disease and decrease its risk of progression. This is the goal of oncological surgery, and starting from these principles radical prostatectomy was favored.

Biogenesis, delivery, and function of extracellular RNA

The Extracellular RNA (exRNA) Communication Consortium was launched by the National Institutes of Health to focus on the extent to which RNA might function in a non-cell-autonomous manner. With the availability of increasingly sensitive tools, small amounts of RNA can be detected in serum, plasma, and other bodily fluids. The exact mechanism(s) by which RNA can be secreted from cells and the mechanisms for the delivery and uptake by recipient cells remain to be determined. This review will summarize current knowledge about the biogenesis and delivery of exRNA and outline projects seeking to understand the functional impact of exRNA.

Diagnostic associations of gene expression signatures in prostate cancer tissue

PURPOSE OF REVIEW

Over the past several years, multiple biomarkers designed to improve prostate cancer risk stratification have become commercially available, while others are still being developed. In this review, we focus on the evidence supporting recently reported biomarkers, with a focus on gene expression signatures.

RECENT FINDINGS

Many recently developed biomarkers are able to improve upon traditional risk assessment at nearly all stages of disease. Prominent examples are reviewed in this article. ConfirmMDx uses gene methylation patterns to improve detection of clinically significant cancer following negative biopsy. Both the Prolaris and Oncotype DX Genomic Prostate Score tests can improve risk stratification following biopsy, especially among men who are eligible for active surveillance. Prolaris and the Decipher genomic classifier have been associated with risk of adverse outcome following prostatectomy, while Oncotype DX is being studied in this setting. Finally, recent reports of the association of androgen receptor-V7 in circulating tumor cells with resistance to enzalutamide and abiraterone raise the possibility of extending the use of genetic biomarkers to advanced disease.

SUMMARY

With the development of multiple genetic expression panels in prostate cancer, careful study and validation of these tests and integration into clinical practice will be critical to realizing the potential of these tools.

Elevated serum microRNA levels associate with absence of high-grade prostate cancer in a retrospective cohort

To reduce treatment of indolent prostate cancer (PCa), biomarkers are needed to improve identification of patients with a low-risk of having aggressive disease. Over-treatment of these patients occurs because of uncertainty in the aggressiveness of the entire tumor based on the biopsies, which do not accurately sample multifocal tumors. Circulating microRNAs (miRNAs) are stable serum markers and differential miRNA levels occur in men with PCa. The goal of this study was to identify circulating miRNAs that were associated with aggressive or indolent PCa. We measured circulating miRNAs in 150 patients prior to surgery and compared the miRNA levels to the pathology of the entire radical prostatectomy specimen. For this study we used an exceptionally well-characterized cohort of patients who had benign prostatic hyperplasia (BPH), low-grade or high-grade PCa. Low-grade was defined as patients with 100% Gleason grade 3 tumor as determined by step-wise sectioning. High-grade PCa patients had 30-90% Gleason grade 4+5 in the tumor. BPH patients had at least two biopsies negative for PCa. Twenty one miRNAs were selected for analysis. The miRNAs were quantified by RT-qPCR and analyzed by logistic regression. High levels of 14 miRNAs were exclusively present in the serum from patients with low-grade PCa or BPH, compared to men with high-grade PCa who had consistently low levels. The expression levels of the 14 miRNAs were combined into a “miR Score” which had a negative predictive value (NPV) of 0.939 to predict absence of high-grade PCa among PCa and BPH patients. Biochemical recurrence (BCR) was known for the PCa patients and a combined “miR Risk Score” accurately classified a subset of patients with low risk of BCR (NPV 0.941). In summary, measurement of serum miRNAs may have pre-surgical utility in combination with clinical risk calculators to identify patients with low risk of harboring aggressive PCa.

MicroRNA in radiotherapy: miRage or miRador?

At least half of all cancer patients will receive radiation therapy. Tumour radioresistance, or the failure to control certain tumours with this treatment, can result in locoregional recurrence; thus there is great interest in understanding the underlying biology and developing strategies to overcome this problem. The expanding investigation of microRNA in cancer suggests that these regulatory factors can influence the DNA damage response, the microenvironment and survival pathways, among other processes, and thereby may affect tumour radioresistance. As microRNA are readily detectable in tumours and biofluids, they hold promise as predictive biomarkers for therapy response and prognosis. This review highlights the current insights on the major ways that microRNA may contribute to tumour radiation response and whether their levels reflect treatment success. We conclude by applying the potential framework of future roles of miR in personalised radiotherapy using prostate cancer clinical management as an example.

Prognostic significance of tissue miR-345 downregulation in non-small cell lung cancer

BACKGROUND

MiRNAs might function as oncogenes or tumor suppressor genes in the tumorigenesis process. Dysregulation of miR-345 is a frequent event in many types of human cancers. However, the tissue miR-345 expression level in non-small cell lung cancer (NSCLC) and its potential clinical significance remains unknown.

MATERIALS AND METHODS

Real-time PCR was conducted to evaluate the expression level of miR-345 in NSCLC tissues as well as cell lines. Then the association between tissue miR-345 expression level and clinical outcome was investigated.

RESULTS

The expression level of miR-345 was significantly decreased in NSCLC tissues and cell lines compared with the controls (P<0.05; P<0.01). Tissue miR-345 expression level was associated with various clinicopathological parameters including LN metastasis (P=0.012), distant metastasis (P=0.007), TNM stage (P=0.008) and grade (P=0.030). In addition, the NSCLC patients in thelow tissue miR-345 expression group had significantly shorter 5-year overall survival time than those in the high tissue miR-345expression group (P=0.016). Multivariate analysis showed that tissue miR-345 was an independent risk factor for NSCLC (HR=3.921, 95% CI: 2.285-10.540; P=0.008).

CONCLUSIONS

The expression level of miR-345 was reduced in NSCLC tissues and cell lines. Low tissue miR-345 expression was associated with progression and poor prognosis of NSCLC, indicating that tissue miR-345 may serve as a novel prognostic marker in NSCLC.

miR-124 exhibits antiproliferative and antiaggressive effects on prostate cancer cells through PACE4 pathway

INTRODUCTION

PACE4 plays an important role in prostate cancer (PCa) proliferation and aggression, which might provide a useful target against prostate cancer. In this study, we had strived to find some key miRNAs to decrease malignancy and invasiveness of PCa through regulating PACE4 expression.

METHODS

Clinically pathological analysis of immunohistochemistry/in situ hybridization was carried out to detect the relationship between PACE4 expression/miRNAs and the malignancy of prostate mass. Prostate cell lines (DU145, C4-2, and BPH-1) were cultured for growth curve, immunocytochemistry analysis, colony formation, Matrigel invasion, and transcriptional/translational expression assay of PACE4-related signaling molecules for confirming the relationship. MiRNAs targeting PACE4 were predicted, validated and further-corroborated using bio-software, real-time PCR, luciferase reporter assay and transfection of miRNA mimics and inhibitor.

RESULTS

It was suggested that PACE4 might reflect the pathological malignancy of prostate lesion from pathology analysis. Moreover, DU145 cells, the highest PACE4-level and related TF expression indicated of the strongest malignancy and invasiveness. It was significantly found that miR-124 was presented with the biggest odd to target PACE4-3'UTR, the capability of decreasing PACE expression and slowing down cell growth and cell invasion.

CONCLUSIONS

It was clear that PACE4 level was closely associated with malignancy and invasiveness of PCa in vivo or in vitro MiR-124, played a crucial role inhibiting PACE4 transcription thus exhibiting obvious effects of antiproliferation and antiaggression of PCa.