Different levels of serum microRNAs in prostate cancer and benign prostatic hyperplasia: evaluation of potential diagnostic and prognostic role

The power of microRNAs as diagnostic and prognostic biomarkers in liquid biopsies

In the last decades, progresses in medical oncology have ameliorated the treatment of patients and their outcome. However, further improvements are still necessary, in particular for certain types of tumors such as pancreatic, gastric, and lung cancer as well as acute myeloid leukemia where early detection and monitoring of the disease are crucial for final patient outcome. Liquid biopsy represents a great advance in the field because it is less invasive, less time-consuming, and safer compared to classical biopsies and it can be useful to monitor the evolution of the disease as well as the response of patients to therapy. Liquid biopsy allows the detection of circulating tumor cells, nucleic acids, and exosomes not only in blood but also in different biological fluids: urine, saliva, pleural effusions, cerebrospinal fluid, and stool. Among the potential biomarkers detectable in liquid biopsies, microRNAs (miRNAs) are gaining more and more attention, since they are easily detectable, quite stable in biological fluids, and show high sensitivity. Many data demonstrate that miRNAs alone or in combination with other biomarkers could improve the diagnostic and prognostic power for many different tumors. Despite this, standardization of methods, sample preparation, and analysis remain challenging and a huge effort should be made to address these issues before miRNA biomarkers can enter the clinic. This review summarizes the main findings in the field of circulating miRNAs in both solid and hematological tumors.

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.

Endorectal power Doppler/grayscale ultrasound-guided biopsies vs. multiparametric MRI/ultrasound fusion-guided biopsies in males with high risk of prostate cancer: A prospective cohort study

Multiparametric MRI fusion with transrectal ultrasound (mpMRI/TRUS)-guided biopsy has the sensitivity of mpMRI with the practicality of TRUS, but males with no cancerous lesion(s) detected on mpMRI have a considerable remaining risk of cancer. Endorectal power Doppler ultrasound improves the sensitivity of grayscale ultrasound-guided biopsies. The objective of the present study was to evaluate the beneficial effect of endorectal power Doppler/grayscale ultrasound-guided biopsy over that of mpMRI/TRUS-guided biopsy for decision-making regarding prostatectomy in males with a high risk of prostate cancer. Data regarding endorectal power Doppler/grayscale ultrasound-guided biopsies and mpMRI/TRUS-guided biopsies of 1,094 males with elevated specific prostate antigen, were included. Radical prostatectomy was performed in males aged <70 years with Gleason scores ≥3+4 in any one of the biopsy reports. The histopathological data of the surgical specimen of 776 males were included in the analysis. Compared to the histopathology of the surgical specimen, endorectal power Doppler/grayscale ultrasound-guided biopsies had a lower sensitivity (0.930 vs. 1.000; P<0.0001) but mpMRI/TRUS-guided biopsies had the same sensitivity (0.990 vs. 1.000; P=0.02). The accuracy of mpMRI/TRUS-guided biopsies was higher than that of endorectal power Doppler/grayscale ultrasound-guided biopsies (0.944 vs. 0.783). On mpMRI, lesions of 105 subjects (10%) with a Likert scale score of <3 were identified. Among them, 14 subjects (2%) had Gleason scores of ≥3+4 as determined by endorectal power Doppler/grayscale ultrasound-guided biopsies. In addition, 20 (2%) false-positive lesions compared to the histopathological analysis of the surgical specimen were identified from mpMRI/TRUS-guided biopsies. In conclusion, mpMRI/TRUS-guided biopsy was indicated to have a moderate performance and endorectal power Doppler/grayscale ultrasound-guided biopsy had a scant performance for decision-making regarding prostatectomy.

Regulation of microRNAs by rape bee pollen on benign prostate hyperplasia in rats

The miRNAs are dysregulated in BPH. Rape bee pollen (RBP) is used to improve benign prostatic hyperplasia (BPH). Whether RBP treats BPH by regulating the dysregulated miRNAs remains unclear. Here, we identified miRNAs regulated along with the improvement of BPH by RBP in posterior lobes of prostate in rats. Firstly, to screened miRNAs might relate to improvement of BPH by RBP, we compared differentially expressed miRNAs between BPH model group and RBP group by high-throughput sequencing. As a result, 10 known miRNAs and 17 novel miRNA were up-regulated in RBP group, and 6 known and 13 novel miRNAs were down-regulated. Secondly, among the known miRNAs, we identified those that might relate to BPH by RT-qPCR, while only rno-miR-184 was screened, so we compared it among normal control group, BPH model group and RBP group. The results showed that rno-miR-184 was significantly lower expressed in BPH group, but up-regulated along with the improvement of BPH by RBP. Moreover, expression level of rno-miR-184 was no difference between RBP group and normal control level. Therefore, we considered that RBP might improve BPH through regulating expression of miRNAs like rno-miR-184 in prostate in rats.

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.

Research status and progress of the RNA or protein biomarkers for prostate cancer

Prostate cancer is a kind of male malignancy. Recently, a large number of studies have reported many potential biomarkers for the diagnosis and prognosis of prostate cancer. In this literature review, we have collected a number of potential biomarkers for prostate cancer reported in the last 5 years. Among them, some are undergoing Phase III clinical trials, and others have been approved by the US Food and Drug Administration. However, most are still in the period of basic research. The review will contribute to future research to find the biomarkers to guide clinicians to make personalized treatment decisions for each prostate cancer patient.

MiR-106a directly targets LIMK1 to inhibit proliferation and EMT of oral carcinoma cells

Background

LIM kinase 1 (LIMK1) expression levels are closely associated with microRNA (miRNA) processing. Higher levels of LIMK1 are reported during the progression of many cancers. Our study explored the interaction between LIMK1 and miR-106a in oral squamous cell carcinoma (OSCC).

Methods

Quantitative RT-PCR was performed to detect the levels of LIMK1 and miR-106a in OSCC tissues and cell lines. The rates of cell proliferation and epithelial-mesenchymal transition (EMT) were assessed to determine the biological functions of miR-106a and LIMK1 in OSCC cells. The mRNA and protein levels of LIMK1 were measured using quantitative RT-PCR and western blotting. Luciferase assays were performed to validate LIMK1 as an miR-106a target in OSCC cells.

Results

We found that the level of miR-106a significantly decreased and the expression of LIMK1 significantly increased in OSCC tissues and cell lines. There was a close association between these changes. Knockdown of LIMK1 significantly inhibited the proliferation and EMT of OSCC cells. The bioinformatics analysis predicted that LIMK1 is a potential target gene of miR-106a and the luciferase reporter assay confirmed that miR-106a could directly target LIMK1. Introduction of miR-106a to OSCC cells had similar effects to LIMK1 silencing. Overexpression of LIMK1 in OSCC cells partially reversed the inhibitory effects of the miR-106a mimic.

Conclusion

MiR-106a inhibited the cell proliferation and EMT of OSCC cells by directly decreasing LIMK1 expression.

Robot-Assisted Surgery in Urology: The Show Must Go On

Initially, robot-assisted surgery (RAS) was developed by the USA forces as a tele-surgery tool in order to perform procedures in war zones without endangering the surgeon [...]

A Non-Enzymatic and Label-Free Fluorescence Bioassay for Ultrasensitive Detection of PSA

The early diagnosis of prostate cancer is very vital for the improvement of patient survival chances. The content of prostate specific antigen (PSA) in serum is closely related to the status of the prostate cancer. We report a fluorescence bioassay, capable of detecting PSA in a non-enzymatic and label-free manner. PSA gives rise to the structural change of a hairpin, consequently triggering the hybridization chain reaction and forming a long-nicked double-helix, which is not adsorbed by graphene oxide. GelRed, as the signal indicator, then binds with dsDNA molecule, thereby producing the fluorescence. The established bioassay has the merits of simple operation, favorable cost-to-benefit ratios, good stability, and specificity. Moreover, the detection limit of this assay is as low as 10 pg/mL, and the linearity range is wide-from 100 pg/mL to 200 ng/mL. At the same time, this bioassay can realize the detection of PSA in biological samples (human serum, saliva, and urine). Therefore, the bioassay provides a potential means for the early diagnosis of prostate cancer.

The role of microRNAs in prostate cancer migration, invasion, and metastasis

Prostate cancer (PCa) is considered the most prevalent malignancy and the second major cause of cancer-related death in males from Western countries. PCa exhibits variable clinical pictures, ranging from dormant to highly metastatic cancer. PCa suffers from poor prognosis and diagnosis markers, and novel biomarkers are required to define disease stages and to design appropriate therapeutic approach by considering the possible genomic and epigenomic differences. MicroRNAs (miRNAs) comprise a class of small noncoding RNAs, which have remarkable functions in cell formation, differentiation, and cancer development and contribute in these processes through controlling the expressions of protein-coding genes by repressing translation or breaking down the messenger RNA in a sequence-specific method. miRNAs in cancer are able to reflect informative data about the current status of disease and this might benefit PCa prognosis and diagnosis since that is concerned to PCa patients and we intend to highlight it in this paper.

Expression levels and co‑targets of miRNA‑126‑3p and miRNA‑126‑5p in lung adenocarcinoma tissues: Αn exploration with RT‑qPCR, microarray and bioinformatic analyses

Lung adenocarcinoma (LUAD) is the most common histological subtype of lung cancer. Previous studies have found that many microRNAs (miRNAs), including miRNA-126-3p, may play a critical role in the development of LUAD. However, no study of LUAD has researched the synergistic effects and co-targets of both miRNA-126-3p and miRNA-126-5p. The present study used real-time quantitative polymerase chain reaction (RT-qPCR) to explore the expression values of miRNA-126-3p and miRNA-126-5p in 101 LUAD and 101 normal lung tissues. Ten relevant microarray datasets were screened to further validate the expression levels of miRNA-126-3p and −5p in LUAD. Twelve prediction tools were employed to obtain potential targets of miRNA-126-3p and miRNA-126-5p. The results showed that both miRNA-126-3p and −5p were expressed significantly lower in LUAD. A significant positive correlation was also present between miRNA-126-3p and −5p expression in LUAD. In addition, lower expression of miRNA-126-3p and −5p was indicative of vascular invasion, lymph node metastasis (LNM), and a later tumor/node/metastasis (TNM) stage of LUAD. The authors obtained 167 targets of miRNA-126-3p and 212 targets of miRNA-126-5p; 44 targets were co-targets of both. Eight co-target genes (IGF2BP1, TRPM8, DUSP4, SOX11, PLOD2, LIN28A, LIN28B and SLC7A11) were initially identified as key genes in LUAD. The results of the present study indicated that the co-regulation of miRNA-126-3p and miRNA-126-5p plays a key role in the development of LUAD, which also suggests a fail-proof mode between miRNA-3p and miRNA-126-5p.

Prognostic value of serum alkaline phosphatase in the survival of prostate cancer: evidence from a meta-analysis

BACKGROUND

Many studies have evaluated the relationship between alkaline phosphatase (ALP) and the prognosis for prostate cancer (PCa). But they have not reached a widespread consensus yet. Therefore, we completed a meta-analysis to ascertain the significance of ALP and the prognosis for PCa.

METHODS

A literature search was performed in the PubMed, Embase, and Web of Science databases. HRs concerning overall survival (OS), progression-free survival (PFS), and cancer-specific survival (CSS) were extracted to evaluate the impacts of ALP on the prognosis for PCa. Subgroup analyses were conducted on different study types, regions, sample sizes, and cutoff values. Sensitivity analysis was performed by removing one study in sequence.

RESULTS

A total of 63 studies from 54 articles with 16,135 patients were included in this meta-analysis. The pooled results indicated that high baseline ALP was associated with obviously poor OS (HR=1.74, 95% CI: 1.47-2.06) and PFS (HR=1.60, 95% CI: 1.13-2.26) in patients with PCa. The pooled HR for bone-specific ALP and OS was 1.76 (95% CI: 1.45-2.15). However, no association between ALP and CSS (HR=1.002, 95% CI: 0.998-1.005) was found for PCa. The results of subgroup analyses were all in accordance with the main findings. Sensitivity analysis suggested that no single study could affect the stability of the results.

CONCLUSION

High serum ALP is significantly associated with poor OS and PFS except for CSS in PCa. ALP is an efficient and convenient biomarker for PCa prognosis.

Protocol for serum exosomal miRNAs analysis in prostate cancer patients treated with radiotherapy

BACKGROUND

Circulating exosomes from prostate cancer (PCa) patients undergoing radiotherapy are attractive candidate biomarkers for monitoring treatment response. Multiple workflows for isolation and content characterization of exosomes in biofluids have been attempted. We report a protocol to isolate and characterize exosomal miRNAs content and assess radiation-induced changes.

METHODS

In this pilot study, we performed targeted exosomal miRNA profiling of 25 serum samples obtained from PCa patients with intermediate- and high-risk disease treated with curative radiotherapy (RT), and controls. Post-treatment blood samples were collected at least 28 days after radiation therapy as a paired follow-up sample. The complete workflow consisted of two phases: I) filtration and polyethylene glycol salt precipitation phase which enriched particles below 200 nm in size followed by characterization using electron microscopy, and II) flow cytometry. Finally, miRNA expression analysis between untreated and treated patient samples was performed using RNA extraction kit, and qRT-PCR.

RESULTS

In our preliminary data, 1 ml of serum from PCa patients showed higher exosomal concentration (3.68E+10) compared to controls (6.07E+08). The overall expression of exosomes after RT was found to be higher compared to untreated samples; the median value changed from 3.68E+10 to 5.40E+10; p = 0.52. Using electron microscopy, we were able to visualize cup-shaped vesicles with morphology and size compatible with exosomes. The bead-based flow cytometry showed positivity for exosomal tetraspanins surface markers CD63 and CD9. All five miRNAs (hsa-let-7a-5p, hsa-miR-141-3p, hsa-miR-145-5p, hsa-miR-21-5p, hsa-miR-99b-5p) have been identified in exosomes. Despite overall changes in hsa-let-7a-5p expression after radiation, the difference was significant only in the high-risk group (p = 0.037). In addition, the radiation response to hsa-miR-21-5p was elevated in the high-risk group compared to the intermediate group (p = 0.036).

CONCLUSIONS

Herewith, we demonstrated a protocol for isolation of serum exosomes and exosomal miRNA amplification. The recovery of exosomal miRNAs and their differential expression after radiation treatment suggests promising biomarker potential that requires further investigation in larger patient cohorts.

Liquid biopsy and PCR-free ultrasensitive detection systems in oncology (Review)

In oncology, liquid biopsy is used in the detection of next-generation analytes, such as tumor cells, cell-free nucleic acids and exosomes in peripheral blood and other body fluids from cancer patients. It is considered one of the most advanced non-invasive diagnostic systems to enable clinically relevant actions and implement precision medicine. Medical actions include, but are not limited to, early diagnosis, staging, prognosis, anticipation (lead time) and the prediction of therapy responses, as well as follow-up. Historically, the applications of liquid biopsy in cancer have focused on circulating tumor cells (CTCs). More recently, this analysis has been extended to circulating free DNA (cfDNA) and microRNAs (miRNAs or miRs) associated with cancer, with potential applications for development into multi-marker diagnostic, prognostic and therapeutic signatures. Liquid biopsies avoid some key limitations of conventional tumor tissue biopsies, including invasive tumor sampling, under-representation of tumor heterogeneity and poor description of clonal evolution during metastatic dissemination, strongly reducing the need for multiple sampling. On the other hand, this approach suffers from important drawbacks, i.e., the fragmentation of cfDNA, the instability of RNA, the low concentrations of certain analytes in body fluids and the confounding presence of normal, as well as aberrant DNAs and RNAs. For these reasons, the analysis of cfDNA has been mostly focused on mutations arising in, and pathognomonicity of, tumor DNA, while the analysis of cfRNA has been mostly focused on miRNA patterns strongly associated with neoplastic transformation/progression. This review lists some major applicative areas, briefly addresses how technology is bypassing liquid biopsy limitations, and places a particular emphasis on novel, PCR-free platforms. The ongoing collaborative efforts of major international consortia are reviewed. In addition to basic and applied research, we will consider technological transfer, including patents, patent applications and available information on clinical trials aimed at verifying the potential of liquid biopsy in cancer.

Next Generation Sequencing of urine exfoliated cells: an approach of prostate cancer microRNAs research

There is emerging evidence that microRNAs (miRNAs) dysregulation is involved in the genesis and the progression of Prostate Cancer (PCa), thus potentially increasing their use in urological clinical practice. This is the first pilot study which utilizes Illumina Deep Sequencing to examine the entire miRNAs spectrum existent in urine exfoliated prostate cells (UEPCs) of PCa patients. A total of 11 male patients with histological diagnosis of PCa were enrolled in the present study. First-catch urine (30 mL) was collected following a prostate massage. Total RNA was extracted from urine and sequenced using an HiSeq2500 System (Illumina). QPCR assay was used to validate the highest NGS results in PCA patients and in age-matched, caucasian men. Remarkably, PCA let-7 family was down-regulated (P < 0.01), compared to the controls. The results of our study support the notion of a relatively high diagnostic value of miRNA family for PCa detection, especially in the let-7 family. The present research confirmed the potential use of miRNAs as non-invasive biomarkers in the diagnosis of PCa, potentially reducing the invasiveness of actual clinical strategy.

A myriad of roles of miR-25 in health and disease

Small non-coding RNAs including microRNAs (miRNAs) have been recently recognized as important regulators of gene expression. MicroRNAs play myriads of roles in physiological processes as well as in the pathogenesis of a number of diseases by translational repression or mRNA destabilization of numerous target genes. The miR-106b-25 cluster is highly conserved in vertebrates and consists of three members including miR-106b, miR-93 and miR-25. MiR-106b and miR-93 share the same seed sequences; however, miR-25 has only a similar seed sequence resulting in different predicted target mRNAs. In this review, we specifically focus on the role of miR-25 in healthy and diseased conditions. Many of miR-25 target mRNAs are involved in biological processes such as cell proliferation, differentiation, and migration, apoptosis, oxidative stress, inflammation, calcium handling, etc. Therefore, it is no surprise that miR-25 has been reported as a key regulator of common cancerous and non-cancerous diseases. MiR-25 plays an important role in the pathogenesis of acute myocardial infarction, left ventricular hypertrophy, heart failure, diabetes mellitus, diabetic nephropathy, tubulointerstitial nephropathy, asthma bronchiale, cerebral ischemia/reperfusion injury, neurodegenerative diseases, schizophrenia, multiple sclerosis, etc. MiR-25 is also a well-described oncogenic miRNA playing a crucial role in the development of many tumor types including brain tumors, lung, breast, ovarian, prostate, thyroid, oesophageal, gastric, colorectal, hepatocellular cancers, etc. In this review, our aim is to discuss the translational therapeutic role of miR-25 in common diseased conditions based on relevant basic research and clinical studies.

Role of Stromal Paracrine Signals in Proliferative Diseases of the Aging Human Prostate

Androgens are essential for the development, differentiation, growth, and function of the prostate through epithelial–stromal interactions. However, androgen concentrations in the hypertrophic human prostate decrease significantly with age, suggesting an inverse correlation between androgen levels and proliferative diseases of the aging prostate. In elderly males, age- and/or androgen-related stromal remodeling is spontaneously induced, i.e., increased fibroblast and myofibroblast numbers, but decreased smooth muscle cell numbers in the prostatic stroma. These fibroblasts produce not only growth factors, cytokines, and extracellular matrix proteins, but also microRNAs as stromal paracrine signals that stimulate prostate epithelial cell proliferation. Surgical or chemical castration is the standard systemic therapy for patients with advanced prostate cancer. Androgen deprivation therapy induces temporary remission, but the majority of patients eventually progress to castration-resistant prostate cancer, which is associated with a high mortality rate. Androgen deprivation therapy-induced stromal remodeling may be involved in the development and progression of castration-resistant prostate cancer. In the tumor microenvironment, activated fibroblasts stimulating prostate cancer cell proliferation are called carcinoma-associated fibroblasts. In this review, we summarize the role of stromal paracrine signals in proliferative diseases of the aging human prostate and discuss the potential clinical applications of carcinoma-associated fibroblast-derived exosomal microRNAs as promising biomarkers.

microRNA expression profiles of scar and normal tissue from patients with posterior urethral stricture caused by pelvic fracture urethral distraction defects

Pelvic fracture urethral distraction defect (PFUDD) seriously affects the quality of life of patients. At present, there are few effective drug treatments available for PFUDD-induced urethral stricture, which is associated with fibrosis and scar formation in urethra lumen. Emerging evidence suggests that microRNAs (miRNAs/miRs) may be involved in the regulation of fibrosis, and analysis of miRNA expression profiles in urethral scar and normal urethra tissues may therefore benefit the discovery of novel treatments for urethral stricture with micro invasive procedures. In the present study, miRNA sequencing and quantitative polymerase chain reaction (qPCR) validation using paired scar and normal tissues from patients with PFUDD, and functional analysis of the miRNAs involved in the fibrosis associated signaling pathway was performed. A total of 94 differentially expressed miRNAs were identified in the scar tissue of patients with PFUDD. Among them, 26 miRNAs had significantly altered expression in the scar tissue compared with the normal tissue from the same patient. qPCR validation confirmed that miR-129-5p was overexpressed in scar tissue. The TGF-β pathway-associated functions of a total of 5 miRNAs (hsa-miR-129-5p, hsa-miR-135a-5p, hsa-miR-363-3p, hsa-miR-6720-3p and hsa-miR-9-5p) were further analyzed, as well as their key molecular targets and functional mechanisms in signaling regulation. To conclude the miRNA sequencing indicated a significantly altered expression of hsa-miR-129-5p, hsa-miR-135a-5p, hsa-miR-363-3p, hsa-miR-6720-3p and hsa-miR-9-5p in patients with PFUDD. These miRNAs and their potential target genes were associated with fibrosis in several diseases, and the data from the present study may help explore potential miRNA targets for future precision treatments for urethral stricture.

Candidate diagnostic miRNAs that can detect cancer in prostate biopsy

BACKGROUND

While histopathological evaluation remains the gold standard for diagnosis of prostate cancer (PCa), sampling errors remain a frequent problem; therefore, use of tissue biomarkers that can distinguish between benign and malignant prostate disease is a potentially beneficial diagnostic strategy.

METHODS

Deep sequencing of the miRNA transcriptome of 14 benign prostatic hyperplasia (BPH) and 60 cancerous and non-cancerous prostate samples extracted from 34 cancer-bearing prostates removed by prostatectomy was performed; of the latter 60 samples, 16, 21, and 23 samples contained <10%, >30%, and no dysplastic cells, respectively. The predictive value of selected miRNAs was then tested by quantitative reverse-transcribed PCR (qRT-PCR), using two separate chemistries, Exiqon and Taqman, to evaluate the tissue samples obtained by prostatectomy. Validation experiments were also performed for a subset of miRNAs by qRT-PCR of 87 prostate core biopsies.

RESULTS

We identified 123 miRNAs significantly dysregulated in PCa (adjusted P-values <0.05); 110 and 13 miRNAs were dysregulated only in cancerous samples and non-cancerous samples extracted from cancer-bearing prostates, respectively, while 31 were dysregulated regardless of the dysplastic cell content of the studied specimens. The clinical utility of eight selected miRNAs was analyzed using the same sample set with two qRT-PCR chemistries. Measurable qRT-PCR signals were obtained for seven and six miRNAs using the Exiqon and Taqman chemistries, respectively, and expression levels of six and four of these miRNAs differed significantly between BPH and PCa samples, regardless of dysplastic cell content. Validation experiments on core biopsies using qRT-PCR confirmed differential expression between BPH and PCa of four miRNAs (miR-187-3p, miR-183-5p, miR-32-5p, and miR-141-5p) using the Exiqon and one miRNA (miR-187-3p) with the Taqman chemistry.

CONCLUSIONS

Our sequencing analyses identified several candidate diagnostic miRNAs and confirmed some which have previously been reported as diagnostic in prostate malignancy. The results of this study suggest also that some of selected miRNAs can differentiate between non-malignant and malignant prostates even when neoplastic cells are missing from the studied specimen.

Immunogenetics of prostate cancer: a still unexplored field of study

The immune system is a double-edged sword with regard to the prostate cancer (PCa) battle. Immunogenetics, the study of the potential role of immune-related polymorphisms, is taking its first steps in the treatment of this malignancy. This review summarizes the most recent papers addressing the potential of immunogenetics in PCa, reporting immune-related polymorphisms associated with tumor aggressiveness, treatment toxicity and patients' prognosis. With some peculiarities, RNASEL, IL-6, IL-10, IL-1β and MMP7 have arisen as the most significant biomarkers in PCa treatment and management, having a potential clinical role. Validation prospective clinical studies are required to translate immunogenetics into precision treatment of PCa.

Diagnostic value of strand-specific miRNA-101-3p and miRNA-101-5p for hepatocellular carcinoma and a bioinformatic analysis of their possible mechanism of action

There is accumulating evidence that miRNA might serve as potential diagnostic and prognostic markers for various types of cancer. Hepatocellular carcinoma (HCC) is the most common type of malignant lesion but the significance of miRNAs in HCC remains largely unknown. The present study aimed to establish the diagnostic value of miR-101-3p/5p in HCC and then further investigate the prospective molecular mechanism via a bioinformatic analysis. First, the miR-101 expression profiles and parallel clinical parameters from 362 HCC patients and 50 adjacent non-HCC tissue samples were downloaded from The Cancer Genome Atlas (TCGA). Second, we aggregated all miR-101-3p/5p expression profiles collected from published literature and the Gene Expression Omnibus and TCGA databases. Subsequently, target genes of miR-101-3p and miR-101-5p were predicted by using the miRWalk database and then overlapped with the differentially expressed genes of HCC identified by natural language processing. Finally, bioinformatic analyses were conducted with the overlapping genes. The level of miR-101 was significantly lower in HCC tissues compared with adjacent non-HCC tissues (P < 0.001), and the area under the curve of the low miR-101 level for HCC diagnosis was 0.925 (P < 0.001). The pooled summary receiver operator characteristic (SROC) of miR-101-3p was 0.86, and the combined SROC curve of miR-101-5p was 0.80. Bioinformatic analysis showed that the target genes of both miR-101-3p and miR-101-5p are involved in several pathways that are associated with HCC. The hub genes for miR-101-3p and miR-101-5p were also found. Our results suggested that both miR-101-3p and miR-101-5p might be potential diagnostic markers in HCC, and that they exert their functions via targeting various prospective genes in the same pathways.

MicroRNA expression profiles in benign prostatic hyperplasia

Although alterations in microRNA (miRNA) expression have been previously investigated prostate cancer, the expression of miRNAs specifically in benign prostate hyperplasia (BPH) of the prostatic stroma remains to be fully elucidated. In the present study, miRNAs and gene expression profiles were investigated using microarray analysis and reverse transcription quantitative‑polymerase chain reaction (RT‑qPCR) in BPH tissue to clarify the associations between miRNA expression and target genes. Prostate tissue samples from five patients with BPH and five healthy men were analyzed using human Affymetrix miRNA and mRNA microarrays and differentially expressed miRNAs were validated using RT‑qPCR with 30 BPH and 5 healthy control samples. A total of 8 miRNAs, including miRNA (miR)‑96‑5p, miR‑1271‑5p, miR‑21‑3p, miR‑96‑5p, miR‑181a‑5p, miR‑143‑3p, miR‑4428 and miR‑106a‑5p were upregulated and 8 miRNAs (miR‑16‑5p, miR‑19b‑5p, miR‑940, miR‑25, miR‑486‑3p, miR‑30a‑3p, let‑7c and miR‑191) were downregulated. Additionally, miR‑96‑5p was demonstrated to have an inhibitory effect on the mRNA expression levels of the following genes: Mechanistic target of rapamycin (MTOR), RPTOR independent companion of MTOR complex 2, syntaxin 10, autophagy‑related protein 9A, zinc finger E‑box binding homeobox 1, caspase 2 and protein kinase c ε. Additionally, 16 differentially expressed miRNAs were identified using RT‑qPCR analysis. This preliminary study provides a solid basis for a further functional study to investigate the underlying regulatory mechanisms of BPH.

miRNA-221 of exosomes originating from bone marrow mesenchymal stem cells promotes oncogenic activity in gastric cancer

Worldwide, gastric cancer (GC) is one of the deadliest malignant tumors of the digestive system. Moreover, microRNAs (miRNAs) of exosomes harbored within cancer cells have been determined to induce inflammatory conditions that accelerate tumor growth and metastasis. Interestingly, the oncogenic role of bone marrow mesenchymal stem cells (BM-MSCs) in the modulation of immunosuppression, tumor invasion, and metastasis was discovered to be partly mediated through the secretion of exosomes. In this article, high expression of miRNA-221 (miR-221) in exosomes of the peripheral blood was determined to be positively correlated with the poor clinical prognosis of GC, especially with respect to tumor, node, and metastases stage. Therefore, the expression of miR-221 in exosomes of the peripheral blood may be an important detection index for GC. Proliferation, migration, invasion, and adhesion to the matrix of GC BGC-823 and SGC-7901 cells were significantly enhanced by exosomes that originated from BM-MSCs that were transfected with miR-221 mimics. In conclusion, extracted exosomes from BM-MSCs transfected with miR-221 oligonucleotides can act as high-efficiency nanocarriers, which can provide sufficient miR-221 oligonucleotides to influence the tumor microenvironment and tumor aggressiveness effectively. Notably, the use of a miR-221 inhibitor with an excellent restraining effect in exosomes provides therapeutic potential for GC in future clinical medicine.

rhPDGF-BB combined with ADSCs in the treatment of Achilles tendinitis via miR-363/PI3 K/Akt pathway

To investigate the mechanism of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) and human adipose-derived stem cells (hADSCs) in the treatment of Achilles tendinitis. Biomechanical indices of stiffness, stress, and maximum load-to-failure were detected by biomechanical test. mRNA and protein levels of miR-363, p-PI3K/AKT, tendon-related genes Collagen I, Scleraxis (Scx), and Tenascin C (TNC) were measured by qRT-PCR and western blot. The proliferation of hADSCs was accessed by MTT assay. Biomechanical indices of stiffness, stress, and maximum load-to-failure, and mRNA and protein levels of tendon-related genes could be improved by rhPDGF-BB or hADSCs alone, and could be further improved by rhPDGF-BB + hADSCs. rhPDGF-BB and hADSCs downregulated the expression of miR-363 and upregulated the levels of p-PI3K/Akt, and rhPDGF-BB + hADSCs further strengthened these effects. In addition, rhPDGF-BB promoted the proliferation of hADSCs in vitro and upregulated the expression of tendon-related genes. miR-363 mimic downregulated the levels of p-PI3K/Akt, miR-363 inhibitor upregulated the levels of p-PI3K/Akt, and miR-363 mimic and PI3K/Akt pathway inhibitor LY294002 reversed the positive effect of rhPDGF-BB on the proliferation of hADSCs, which suggested that rhPDGF-BB promoted the proliferation of hADSCs via miR-363/PI3K/Akt pathway. Biomechanical indices and tendon-related genes could be improved by rhPDGF-BB and hADSCs. Moreover, rhPDGF-BB promoted the proliferation of hADSCs via miR-363/PI3K/Akt pathway, indicating that rhPDGF-BB combined with ADSCs could treat Achilles tendinitis via miR-363/PI3K/Akt pathway.

Resveratrol and pterostilbene as a microRNA-mediated chemopreventive and therapeutic strategy in prostate cancer

Growing evidence indicates that deregulation of the epigenetic machinery comprising the microRNA (miRNA) network is a critical factor in the progression of various diseases, including cancer. Concurrently, dietary phytochemicals are being intensively studied for their miRNA-mediated health-beneficial properties, such as anti-inflammatory, cardioprotective, antioxidative, and anticancer properties. Available experimental data have suggested that dietary polyphenols may be effective miRNA-modulating chemopreventive and therapeutic agents. Moreover, noninvasive detection of changes in miRNA expression in liquid biopsies opens enormous possibilities for their clinical utilization as novel prognostic and predictive biomarkers. In our published studies, we identified resveratrol-regulated miRNA profiles in prostate cancer. Resveratrol downregulated the phosphatase and tensin homolog (PTEN)-targeting members of the oncogenic miR-17 family of miRNAs, which are overexpressed in prostate cancer. We have functionally validated the miRNA-mediated ability of resveratrol and its potent analog pterostilbene to rescue the tumor suppressor activity of PTEN in vitro and in vivo. Taken together, our findings implicate the use of resveratrol and its analogs as an attractive miRNA-mediated chemopreventive and therapeutic strategy in prostate cancer and the use of circulating miRNAs as potential predictive biomarkers for clinical development.

A Panel of MicroRNAs as Diagnostic Biomarkers for the Identification of Prostate Cancer

Prostate cancer is the most common non-cutaneous cancer among men; yet, current diagnostic methods are insufficient, and more reliable diagnostic markers need to be developed. One answer that can bridge this gap may lie in microRNAs. These small RNA molecules impact protein expression at the translational level, regulating important cellular pathways, the dysregulation of which can exert tumorigenic effects contributing to cancer. In this study, high throughput sequencing of small RNAs extracted from blood from 28 prostate cancer patients at initial stages of diagnosis and prior to treatment was used to identify microRNAs that could be utilized as diagnostic biomarkers for prostate cancer compared to 12 healthy controls. In addition, a group of four microRNAs (miR-1468-3p, miR-146a-5p, miR-1538 and miR-197-3p) was identified as normalization standards for subsequent qRT-PCR confirmation. qRT-PCR analysis corroborated microRNA sequencing results for the seven top dysregulated microRNAs. The abundance of four microRNAs (miR-127-3p, miR-204-5p, miR-329-3p and miR-487b-3p) was upregulated in blood, whereas the levels of three microRNAs (miR-32-5p, miR-20a-5p and miR-454-3p) were downregulated. Data analysis of the receiver operating curves for these selected microRNAs exhibited a better correlation with prostate cancer than PSA (prostate-specific antigen), the current gold standard for prostate cancer detection. In summary, a panel of seven microRNAs is proposed, many of which have prostate-specific targets, which may represent a significant improvement over current testing methods.

Circulating cell-free microRNAs as clinical cancer biomarkers

MicroRNAs (miRNAs) are non-coding small RNAs that are master regulators of genic expression and consequently of many cellular processes. But their expression is often deregulated in human tumors leading to cancer development. Recently miRNAs were discovered in body fluids (serum, plasma and others) and their levels have often been reported to be altered in patients. Circulating miRNAs became one of the most promising biomarkers in oncology for early diagnosis, prognosis and therapeutic response prediction. Here we describe the origins and roles of miRNAs, and summarize the most recent studies focusing on their usefulness as cancer biomarkers in lung, breast, colon, prostate, ovary cancers and melanoma. Lastly, we describe the main methodologies related to miRNA detection, which should be standardized for their use in clinical practice.

MiR-346 suppresses cell proliferation through SMYD3 dependent approach in hepatocellular carcinoma

BACKGROUND & AIMS

The miRNAs are demonstrated to be involved in the carcinogenesis of hepatocellular carcinoma (HCC) and some exhibit potential value for oncotherapy. This study was designed to explore the role of miR-346 in the pathogenesis of hepatocellular carcinoma.

METHODS

High throughput screening was employed following with Real time-PCR to investigate the candidate miRNAs. 5-ethynyl-2-deoxyuridine (EdU) assay, CCK-8, transwell assay, cell cycle assay, luciferase reporter assay, western blot and mice xenotransplantation model were performed in the present study.

RESULTS

We found miR-346 was significantly down-regulated in the HCC tissues compared with the non-tumor controls and was associated with the tumor size and TNM grade. Additionally, the in vitro and in vivo assays confirmed that miR-346 suppressed the proliferation of HCC. Then, bioinformatic algorithms and luciferase reporter assays proved that miR-346 directly targeted SET and MYND domain containing 3(SMYD3). We also performed the rescue experiments by inhibiting the expression of SMYD3 and found the down-regulation of SMYD3 could neutralize the inhibitory effects of miR-346 on HCC. At last, the cox proportional hazards analysis showed that low expression of miR-346 was an an independent prognostic factor for HCC.

CONCLUSION

Our findings illuminated miR-346 targeting SMYD3 to inhibit the proliferation of HCC and its down-regulation predicts a poor prognosis.

Low expression of microRNA-30c promotes prostate cancer cells invasion involved in downregulation of KRAS protein

Aberrant microRNA expression is associated with tumor development. The present study aimed to elucidate the role of miR-30c in the development of prostate cancer. Quantitative polymerase chain reaction was performed to compare miR-30c expression in LNCaP, DU145, PC-3 and RWPE-1 cell lines. Lentivirus expressing miR-30c was used to create stable overexpression cell lines to investigate the effects of miR-30c overexpression on cell proliferation, migration and invasion, which were determined in the prostate cancer cell line PC-3 by MTT, colony formation, wound healing and Transwell assays. Effects of miR-30c on KRAS were examined by western blot analysis. miR-30c expression was significantly lower (P<0.05) in the PC-3 cell line compared with LNCaP, DU145 and RWPE-1 cell lines. miR-30c overexpression in PC-3 inhibited tumor cell proliferation, migration and invasion in vitro. Furthermore, KRAS protein expression was downregulated in miR-30c overexpression cell lines compared with the negative control (NC) group (P<0.05). The present results demonstrated that overexpression of miR-30c inhibits prostate cancer cell line proliferation, migration and invasion, which was possibly caused by downregulation of KRAS protein by miR-30c. The data implicate miR-30c in the prognosis and treatment of prostate cancer.

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.