DNMT3A epigenetically regulates key microRNAs involved in epithelial-to-mesenchymal transition in prostate cancer

Epithelial-to-Mesenchymal Transition (EMT) is involved in prostate cancer metastatic progression, and its plasticity suggests epigenetic implications. Deregulation of DNMTs and several miRNAs plays a relevant role in EMT, but their interplay has not been clarified yet. In this study we provide evidence that DNMT3A interaction with several miRNAs has a central role in an ex-vivo EMT prostate cancer model obtained via exposure of PC3 cells to conditioned media from cancer-associated fibroblasts (CM-CAFs). The analysis of the alterations of the miRNA profile shows that miR-200 family (miR-200a/200b/429, miR-200c/141), miR-205, and miR-203, known to modulate key EMT factors, are downregulated and hyper-methylated at their promoters. DNMT3A (mainly isoform a) is recruited onto these miRNA promoters, coupled with the increase of H3K27me3/H3K9me3 and/or the decrease of H3K4me3/H3K36me3. Most interestingly, our results reveal the differential expression of two DNMT3A isoforms (a and b) during ex-vivo EMT and a regulatory feedback loop between miR-429 and DNMT3A that can promote and sustain the transition toward a more mesenchymal phenotype. We demonstrate the ability of miR-429 to target DNMT3A 3'UTR and modulate the expression of EMT factors, in particular ZEB1. Survey of the PRAD-TCGA data set shows that patients expressing an EMT-like signature are indeed characterized by down-regulation of the same miRNAs with a diffused hyper-methylation at miR-200c/141 and miR-200a/200b/429 promoters. Finally, we show that miR-1260a also targets DNMT3A, although it does not seem involved in EMT in prostate cancer.

Angiogenesis and Anti-Angiogenic Treatment in Prostate Cancer: Mechanisms of Action and Molecular Targets

Prostate cancer (PC) is the most common cancer in men and the second leading cause of cancer-related death worldwide. Many therapeutic advances over the last two decades have led to an improvement in the survival of patients with metastatic PC, yet the majority of these patients still succumb to their disease. Antiagiogenic therapies have shown substantial benefits for many types of cancer but only a marginal benefit for PC. Ongoing clinical trials investigate antiangiogenic monotherapies or combination therapies. Despite the important role of angiogenesis in PC, clinical trials in refractory castration-resistant PC (CRPC) have demonstrated increased toxicity with no clinical benefit. A better understanding of the mechanism of angiogenesis may help to understand the failure of trials, possibly leading to the development of new targeted anti-angiogenic therapies in PC. These could include the identification of specific subsets of patients who might benefit from these therapeutic strategies. This paper provides a comprehensive review of the pathways involved in the angiogenesis, the chemotherapeutic agents with antiangiogenic activity, the available studies on anti-angiogenic agents and the potential mechanisms of resistance.

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

BACKGROUND

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

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS AND DISCUSSION

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

CONCLUSION

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

Isolation of Extracellular Vesicles from Biological Fluids via the Aggregation-Precipitation Approach for Downstream miRNAs Detection

Extracellular vesicles (EVs) have high potential as sources of biomarkers for non-invasive diagnostics. Thus, a simple and productive method of EV isolation is demanded for certain scientific and medical applications of EVs. Here we aim to develop a simple and effective method of EV isolation from different biofluids, suitable for both scientific, and clinical analyses of miRNAs transported by EVs. The proposed aggregation-precipitation method is based on the aggregation of EVs using dextran blue and the subsequent precipitation of EVs using 1.5% polyethylene glycol solutions. The developed method allows the effective isolation of EVs from plasma and urine. As shown using TEM, dynamic light scattering, and miRNA analyses, this method is not inferior to ultracentrifugation-based EV isolation in terms of its efficacy, lack of inhibitors for polymerase reactions and applicable for both healthy donors and cancer patients. This method is fast, simple, does not need complicated equipment, can be adapted for different biofluids, and has a low cost. The aggregation-precipitation method of EV isolation accessible and suitable for both research and clinical laboratories. This method has the potential to increase the diagnostic and prognostic utilization of EVs and miRNA-based diagnostics of urogenital pathologies.

The PTEN Conundrum: How to Target PTEN-Deficient Prostate Cancer

Loss of the tumor suppressor phosphatase and tensin homologue deleted on chromosome 10 (PTEN), which negatively regulates the PI3K-AKT-mTOR pathway, is strongly linked to advanced prostate cancer progression and poor clinical outcome. Accordingly, several therapeutic approaches are currently being explored to combat PTEN-deficient tumors. These include classical inhibition of the PI3K-AKT-mTOR signaling network, as well as new approaches that restore PTEN function, or target PTEN regulation of chromosome stability, DNA damage repair and the tumor microenvironment. While targeting PTEN-deficient prostate cancer remains a clinical challenge, new advances in the field of precision medicine indicate that PTEN loss provides a valuable biomarker to stratify prostate cancer patients for treatments, which may improve overall outcome. Here, we discuss the clinical implications of PTEN loss in the management of prostate cancer and review recent therapeutic advances in targeting PTEN-deficient prostate cancer. Deepening our understanding of how PTEN loss contributes to prostate cancer growth and therapeutic resistance will inform the design of future clinical studies and precision-medicine strategies that will ultimately improve patient care.

Thyroid hormone, gene expression, and Central Nervous System: Where we are

Thyroid hormones (TH; T3 and T4) play a fundamental role in the fetal stage to the adult phase, controlling gene and protein expression in virtually all tissues. The endocrine and CNS systems have relevant interaction, and the TH are pivotal for the proper functioning of the CNS. A slight failure to regulate TH availability during pregnancy and/or childhood can lead to neurological disorders, for example, autism and cognitive impairment, or depression. In this review, we highlight how TH acts in controlling gene expression, its role in the CNS, and what substances widely found in the environment can cause in this tissue. We highlight the role of Endocrine Disruptors used on an everyday basis in the processing of mRNAs responsible for neurodevelopment. We conclude that TH, more precisely T3, acts mainly throughout its nuclear receptors, that the deficiency of this hormone, either due to the lack of its main substrate iodine, or by to incorrect organification of T4 and T3 in the gland, or by a mutation in transporters, receptors and deiodinases may cause mild (dysregulated mood in adulthood) to severe neurological impairment (Allan-Herndon-Dudley syndrome, presented as early as childhood); T3 is responsible for the expression of numerous CNS genes related to oxygen transport, growth factors, myelination, cell maturation. Substances present in the environment and widely used can interfere with the functioning of the thyroid gland, the action of TH, and the functioning of the CNS.

The Influence of Radical Prostatectomy on the Expression of Cell-Free MiRNA

MiRNAs of blood and urine have been shown to represent a convenient source of biomarkers for prostate cancer (PCa) diagnosis and assessment of the therapy effectiveness due to their high stability and representation and the low invasiveness of sample collection. Here, we studied the influence of radical prostatectomy (RP) on the expression of 12 cell-free miRNAs previously shown as potential markers of PCa (i.e., 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). The relative expression of the miRNAs combined into 31 paired ratios was evaluated in the urine extracellular vesicles (EVs), clarified urine (CU) and blood plasma of healthy donors, pre- and post-RP samples of PCa patients. Nineteen miRNA ratios based on combinations of ten of the miRNAs (miR-19b, miR-30e, miR-31, miR-125b, miR-200b, miR-205, miR-375, miR-378, miR-425, and miR-660) were altered by RP. The comparative expression analysis of the cell-free miRNA ratios between healthy donors and PCa patients revealed miR-125b/miR-30e and miR-375/miR-30e as potential markers for evaluating therapeutic efficacy. MiR-378/miR-19b, miR-425/miR-19b, miR-200/miR-30e, miR-660/miR-30e, and miR-205/miR-30e had minor prognostic value but could be used to increase the steadiness of the diagnostic system. The urine EVs had the highest potential as a source of markers.

Recent advances in circulating nucleic acids in oncology

Circulating cell-free DNA (cfDNA) is one of the fastest growing and most exciting areas in oncology in recent years. Its potential clinical uses cover now each phase of cancer patient management care (predictive information, detection of the minimal residual disease, early detection of resistance, treatment monitoring, recurrence surveillance, and cancer early detection/screening). This review relates the recent advances in the application of circulating DNA or RNA in oncology building on unpublished or initial findings/work presented at the 10th international symposium on circulating nucleic acids in plasma and serum held in Montpellier from the 20th to the 22nd of September 2017. This year, presenters revealed their latest data and crucial observations notably in relation to (i) the circulating cell-free (cfDNA) structure and implications regarding their optimal detection; (ii) their role in the metastatic or immunological processes; (iii) evaluation of miRNA panels for cancer patient follow up; (iv) the detection of the minimal residual disease; (v) the evaluation of a screening tests for cancer using cfDNA analysis; and (vi) elements of preanalytical guidelines. This work reviews the recent progresses in the field brought to light in the meeting, as well as in the most important reports from the literature, past and present. It proposes a broader picture of the basic research and its potential, and of the implementation and current challenges in the use of circulating nucleic acids in oncology.

Cationic Polymer Nanoparticles-Mediated Delivery of miR-124 Impairs Tumorigenicity of Prostate Cancer Cells

MicroRNAs (miRNAs) play a pivotal role in regulating the expression of genes involved in tumor development, invasion, and metastasis. In particular, microRNA-124 (miR-124) modulates the expression of carnitine palmitoyltransferase 1A (CPT1A) at the post-transcriptional level, impairing the ability of androgen-independent prostate cancer (PC3) cells to completely metabolize lipid substrates. However, the clinical translation of miRNAs requires the development of effective and safe delivery systems able to protect nucleic acids from degradation. Herein, biodegradable polyethyleneimine-functionalized polyhydroxybutyrate nanoparticles (PHB-PEI NPs) were prepared by aminolysis and used as cationic non-viral vectors to complex and deliver miR-124 in PC3 cells. Notably, the PHB-PEI NPs/miRNA complex effectively protected miR-124 from RNAse degradation, resulting in a 30% increase in delivery efficiency in PC3 cells compared to a commercial transfection agent (Lipofectamine RNAiMAX). Furthermore, the NPs-delivered miR-124 successfully impaired hallmarks of tumorigenicity, such as cell proliferation, motility, and colony formation, through CPT1A modulation. These results demonstrate that the use of PHB-PEI NPs represents a suitable and convenient strategy to develop novel nanomaterials with excellent biocompatibility and high transfection efficiency for cancer therapy.

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.

MicroRNA-769-5p Inhibits Pancreatic Ductal Adenocarcinoma Progression by Directly Targeting and Downregulating ETS Proto-Oncogene 1

Purpose

MicroRNA-769-5p (miR-769) is aberrantly expressed and plays crucial roles in non-small cell lung cancer and melanoma. However, the expression pattern, biological role, and mechanisms of action of miR-769 in pancreatic ductal adenocarcinoma (PDAC) are yet to be fully elucidated. Therefore, we attempted to determine the potential regulatory function of miR-769 in PDAC progression and to explore the underlying mechanisms in detail.

Methods

In this study, reverse-transcription quantitative polymerase chain reaction was carried out to determine the expression profile of miR-769 in PDAC. A series of experiments, including a Cell Counting Kit-8 assay, flow-cytometric analysis, Transwell migration and invasion assays, and a xenograft animal model, were applied to test whether miR-769 affects the malignancy of PDAC.

Results

We found that miR-769 was significantly underexpressed in PDAC tissues and cell lines. The low miR-769 expression significantly correlated with the TNM stage and lymph node metastasis. Patients with PDAC harboring low miR-769 expression showed shorter overall survival than did the patients with high miR-769 expression. Forced upregulation of miR-769 suppressed PDAC cell proliferation, migration, and invasion in vitro; promoted apoptosis in vitro; and hindered tumor growth in vivo. Experiments on the mechanism identified ETS proto-oncogene 1 (ETS1) as a direct target gene of miR-769 in PDAC cells. Furthermore, ETS1 turned out to be upregulated in PDAC tissue samples, and the upregulation of ETS1 negatively correlated with miR-769 expression. Moreover, ETS1 knockdown simulated the tumor-suppressive effects of miR-769 overexpression on PDAC cells. Besides, ETS1 reintroduction attenuated the antitumor actions of miR-769 upregulation in PDAC cells.

Conclusion

Our findings indicate that miR-769 performs tumor-suppressive functions in PDAC by directly targeting ETS1, and this miRNA may represent a potential therapeutic target for the development of anticancer therapies.

Role of non-coding RNA in the pathogenesis of depression

Depression is increasingly threatening human health as a serious psychological problem. However, it is remarkable that the precise mechanism underlying depression remains unelucidated. Recent studies have clarified that non-coding RNA, including but not limited to microRNA, long non-coding RNA, and circular RNA, plays an important role in the pathogenesis of depression. The research results cited in this paper reveal the origin, expression, distribution, function, and mechanism of microRNA in the nervous system. MicroRNA is involved in regulation of life activities, including growth, immune reaction, haematopoiesis, and metabolism, which are significant for maintaining normal physiological functions. Moreover, microRNA plays an important role in cell death and proliferation, development of cancer, and disease prognosis. Here, we also introduce the general research status of long non-coding RNA and circular RNA. Next, descriptive study methods, including fluorescence quantitative polymerase chain reaction, northern blot, microarray technology, RNA-seq, and fluorescent in situ hybridization are discussed. Functional study methods are also summarized and divided into gain- and loss-of-function studies. Moreover, the roles of non-coding RNA in the pathogenesis of depression, including neurogenesis, synaptic plasticity, brain-derived neurotrophic factor expression, HPA axis regulation, neurotransmission, neuropeptide expression, neuro-inflammation, and polyamine synthesis are discussed. Nevertheless, many unknown associations between non-coding RNA and depression remain to be clarified.

miR-1303 promotes the proliferation, migration and invasion of prostate cancer cells through regulating the Wnt/β-catenin pathway by targeting DKK3

MicroRNA-1303 (miR-1303) is involved in the tumorigenesis and progression of several cancers, and yet the role of miR-1303 in prostate cancer (PCa) and its underlying mechanism are unknown. To explore this issue, the present study aimed to use PCa tissues, cell lines and a PCa-engrafted mouse model to determine the expression and roles of miR-1303 in PCa. Furthermore, a series of experiments were conducted to explore the underlying mechanisms of action of miR-1303 in PCa cells. miR-1303 was demonstrated to be highly expressed in PCa tissues and cell lines. The level of miR-1303 expression was closely associated with higher Gleason scores and a more developed tumor stage in patients with PCa, and patients with higher levels of miR-1303 displayed a reduced overall survival rate. miR-1303 overexpression promoted the proliferation, migration and invasion of PCa cells. In vivo experiments showed that miR-1303 inhibition suppressed the growth of PCa tumors in mice. Additionally, dickkopf Wnt signaling pathway inhibitor 3 (DKK3) was identified as a target of miR-1303. Knockdown of miR-1303 suppressed the proliferation, migration and invasion of PCa cells, increased DKK3 expression, and inhibited the activity of the Wnt/β-catenin pathway. In conclusion, miR-1303 may promote proliferation, migration and invasion of PCa cells through activating the Wnt/β-catenin pathway by regulating DKK3 expression. These results indicated that miR-1303 may be considered as a potential biomarker for PCa treatment.

miR-628 reduces prostate cancer proliferation and invasion via the FGFR2 signaling pathway

Recently, microRNA (miR)-628 was identified as a potential biomarker for several types of cancer, including prostate cancer (PCa). The aim of the present study was to investigate miR-628 expression and its underlying mechanism in PCa cell proliferation and invasion and the fibroblast growth factor receptor 2 (FGFR2) signaling pathway. The serum expression levels of miR-628, prostate-specific antigen, fibroblast growth factor 1, and FGFR2 were examined in patients with PCa. The relative expression levels of miR-628 and FGFR2 were determined by reverse transcription-quantitative polymerase chain reaction in PCa cells following transfection with miR-628-5p mimic or inhibitor. In addition, the protein expression level of FGFR2 was examined by western blot analysis following transfection with miR-628-5p mimic or inhibitor. Following bioinformatics analysis, dual-luciferase reporter assay was used to confirm the direct interaction between miR-628 and FGFR2. The current study demonstrated that the protein expression level of FGFR2 decreased following transfection with miR-628-5p mimic and increased following transfection with miR-628-5p inhibitor. Similarly, the proliferation and invasion of PCa cells were significantly enhanced following transfection with miR-628-5p inhibitor. By contrast, the proliferation and invasion of PCa cells were significantly inhibited following transfection with miR-628 mimic. Therefore, downregulating the expression level of miR-628 may increase the expression level of FGF in PCa, thereby promoting tumor proliferation and invasion. In conclusion, the FGF signaling pathway may be involved in promoting PCa cell proliferation and invasion. miR-628 may be a potential therapeutic target for patients with PCa.

microRNA-877 inhibits malignant progression of colorectal cancer by directly targeting MTDH and regulating the PTEN/Akt pathway

Background: Recently, microRNA-877-5p (miR-877) was recognized as a cancer-associated miRNA in hepatocellular and renal cell carcinomas. However, little is known regarding its expression pattern and role in colorectal cancer (CRC) tumorigenesis.

Material and methods: In the present study, reverse-transcription quantitative polymerase chain reaction was performed to detect miR-877 expression in CRC tissues and cell lines. A series of functional experiments were used to determine the effects of miR-877 upregulation on CRC cell proliferation, colony formation, apoptosis, migration, and invasion. In addition, the regulatory role of miR-877 in tumor growth was examined in vivo using a xenograft experiment. More importantly, the mechanisms underlying the action of miR-877 in CRC were explored.

Results: A significant decrease in the expression of miR-877 was observed in CRC tissues and cell lines. Low miR-877 expression correlated with lymph node metastasis and TNM stage of CRC patients. Functional experiments revealed that ectopic expression of miR-877 suppressed CRC cell proliferation and colony formation ability, induced cell apoptosis, inhibited cell migration and invasion in vitro, and reduced tumor growth in vivo. Metadherin (MTDH) was recognized as a direct target of miR-877 in CRC cells. It was notably overexpressed in CRC tissues, and its expression was inversely correlated with that of miR-877 expression. Furthermore, MTDH knockdown simulated the tumor suppressor activity of miR-877 in CRC cells. MTDH restoration impaired the suppressive effects of miR-877 on malignant phenotypes of CRC cells. In addition, miR-877 inhibited the activation of the PTEN/Akt signaling pathway by regulating MTDH expression both in vitro and in vivo.

Conclusion: Collectively, these results demonstrate that miR-877 inhibits the progression of CRC, at least partly by the direct targeting of MTDH and regulation of the PTEN/Akt pathway. Thus, miR-877 may serve as a potential therapeutic target for the treatment of patients with CRC.

MicroRNA-664 targets paired box protein 6 to inhibit the oncogenicity of pancreatic ductal adenocarcinoma

The abnormal expression of microRNAs (miRNAs or miRs) with oncogenic or tumor‑suppressive roles in pancreatic ductal adenocarcinoma (PDAC) has been widely reported in recent years, and these dysregulated miRNAs are implicated in the formation and progression of PDAC. Therefore, an investigation into the functional roles of miRNAs in PDAC may facilitate the identification of effective therapeutic targets. miRNA‑664 (miR‑664) has been found to be aberrantly expressed and to play crucial roles in several human cancer types. However, the expression pattern and functional roles of miR‑664 in the malignant capacity of PDAC have yet to be elucidated. In this study, the results revealed that miR‑664 was clearly downregulated in PDAC tissues and cell lines. The low miR‑664 expression was strongly associated with pathological T stage and lymph node metastasis of the patients with PDAC. Patients with PDAC with a low miR‑664 expression had a poorer overall survival and a worse disease‑free survival than those patients with a high miR‑664 level. Functional experiments suggested that exogenous miR‑664 expression suppressed the growth and metastasis of PDAC cells in vitro, whereas miR‑664 downregulation exerted the opposite effects. In addition, miR‑664 suppressed the tumor growth of PDAC cells in vivo. Mechanistically, paired box protein 6 (PAX6) was identified as a direct target gene of miR‑664 in PDAC cells. Furthermore, PAX6 was upregulated in PDAC tissues, and its upregulation inversely correlated with miR‑664 levels. Moreover, the silencing of PAX6 mimicked the effects of miR‑664 upregulation in PDAC cells, and the recovered expression of PAX6 eliminated the effects of miR‑664 on PDAC cells. Notably, miR‑664 could inhibit the activation of PI3K/Akt pathway in PDAC cells in vitro and in vivo. Cumulatively, these results indicate an important role of the miR‑664/PAX6 pathway in suppressing the aggressiveness of PDAC cells, suggesting that miR‑664 may be an attractive therapeutic target for the treatment of patients with this fatal disease.

MicroRNA-508 is downregulated in clear cell renal cell carcinoma and targets ZEB1 to suppress cell proliferation and invasion

Recent studies have identified several microRNAs (miRNAs/miRs) that are dysregulated in clear cell renal cell carcinoma (ccRCC), and their dysregulation may serve important roles in the occurrence and development of ccRCC. Therefore, understanding the expression pattern and functional roles of miRNAs in ccRCC may facilitate the identification of novel therapeutic targets for the treatment of ccRCC. In the current study, reverse transcription-quantitative polymerase chain reaction was used to determine miR-508 expression levels in ccRCC tissue samples and cell lines. The cell counting kit-8 and in vitro Transwell invasion assays were used to examine the effects of miR-508 overexpression on ccRCC cell proliferation and invasion, respectively. In addition, bioinformatics analysis and dual-luciferase reporter gene assays were used to investigate the underlying mechanism of miR-508 in ccRCC cells. Furthermore, the regulatory role of miR-508 on zinc finger E-box-binding homeobox 1 (ZEB1) mRNA and protein expression in ccRCC cells was investigated using RT-qPCR and western blot analysis, respectively. Additionally, the association between miR-508 and ZEB1 expression in ccRCC tissue samples was examined. Rescue experiments were performed to determine whether the tumor suppressive effects of miR-508 may be mediated by ZEB1 in ccRCC cells. The results of the current study demonstrated that miR-508 expression was significantly downregulated in ccRCC tissue samples and cell lines. In addition, miR-508 overexpression significantly decreased the proliferation and invasion of ccRCC cells. ZEB1 was identified as a direct target gene of miR-508 in ccRCC cells and the relative expression level of ZEB1 mRNA was significantly increased in ccRCC tissue samples. Furthermore, a negative correlation between miR-508 and ZEB1 expression was identified in ccRCC tissues. ZEB1 knockdown exhibited a functional role similar to miR-508 overexpression in ccRCC cells, and restoration of ZEB1 expression significantly reversed the inhibitory effects of miR-508 on the malignant phenotype of ccRCC cells. Taken together, the results of the current study demonstrated that miR-508 may serve a tumor suppressive role in ccRCC via direct targeting of ZEB1. MiR-508 may present a novel and efficient therapeutic target for the treatment of patients with ccRCC.

MicroRNA‑758 inhibits tumorous behavior in tongue squamous cell carcinoma by directly targeting metadherin

Numerous microRNAs (miRNAs) are dysregulated in tongue squamous cell carcinoma (TSCC), and their dysregulation has been demonstrated to have a strong correlation with TSCC progression via regulation of their targets. Therefore, miRNAs have potential use in the diagnosis and treatment of patients with TSCC. In the present study, miRNA‑758 (miR‑758) expression in TSCC tissues and cell lines was detected through reverse transcription‑quantitative polymerase chain reaction, and the effects of miR‑758 on TSCC cell proliferation and invasion were investigated by using Cell Counting kit‑8 and Transwell invasion assays. A luciferase reporter assay was performed to determine the target interaction between miR‑758 and metadherin (MTDH) in TSCC cells. The results revealed that miR‑758 was downregulated in TSCC tissues and cell lines. miR‑758 overexpression restricted the proliferation and invasion of TSCC cells. Additionally, MTDH was verified as a direct target gene of miR‑758 in TSCC cells. Furthermore, MTDH was observed to be upregulated in TSCC tissues, and the upregulation of MTDH was inversely correlated with miR‑758 expression. Moreover, restored MTDH expression significantly counteracted the suppressive effects of miR‑758 overexpression on TSCC cells. These results suggested that miR‑758 may prevent TSCC progression and development by directly targeting MTDH, thereby providing evidence that miR‑758 is a novel therapeutic target for the treatment of patients with TSCC.

Searching for the Novel Specific Predictors of Prostate Cancer in Urine: The Analysis of 84 miRNA Expression

The aim of this study was to investigate miRNA profiles of clarified urine supernatant and combined urine vesicle fractions of healthy donors and patients with benign prostatic hyperplasia and prostate cancer (PCa). The comparative analysis of miRNA expression was conducted with a custom miRCURY LNA miRNA qPCR panel. Significant combinations of miRNA pairs were selected by the RandomForest-based feature selection algorithm Boruta; the difference of the medians between the groups and a 95% confidence interval was built using the bootstrap approach. The Asymptotic Wilcoxon-Mann-Whitney Test was performed for miRNA combinations to compare different groups of donors. Benjamini-Hochberg correction was used to adjust the statistical significance for multiple comparisons. The most diagnostically significant miRNAs pairs were miR-107-miR-26b.5p and miR-375.3p-miR-26b.5p in the urine supernatant fraction that discriminated the group of healthy patients and PCa patients, as well as miR-31.5p-miR-16.5p, miR-31.5p-miR-200b, miR-31.5p-miR-30e.3p and miR-31.5p-miR-660.5p in the fraction extracellular vesicles that were different between healthy men and benign prostate hyperplasia patients. Such statistical criteria as the occurrence of individual significant miRNA pairs in the total number of comparisons, median ΔCt difference, and confidence interval can be useful tools for determining reliable markers of PCa.