Elevated expression of prostate cancer-associated genes is linked to down-regulation of microRNAs

PSMA guided approach for bIoCHEmical relapse after prostatectomy- (PSICHE) trial (NCT05022914). Detection rate and treatment decision after 68Ga-PSMA PET/CT within a prospective study

BACKGROUND

Ultrasensitive imaging has been demonstrated to influence biochemical relapse treatment. PSICHE is a multicentric prospective study, aimed at exploring detection rate with 68Ga-PSMA-11 positron emission tomography/computed tomography (PET/CT) and outcomes with a predefined treatment algorithm tailored to the imaging.

METHODS

Patients affected by biochemical recurrence after surgery (prostate specific antigen [PSA] > 0.2 < 1 ng/mL) underwent staging with 68Ga-PSMA PET/CT. Management followed this treatment algorithm accordingly with PSMA results: prostate bed salvage radiotherapy (SRT) if negative or positive within prostate bed, stereotactic body radiotherapy (SBRT) if pelvic nodal recurrences or oligometastatic disease, androgen deprivation therapy (ADT) if nonoligometastatic disease. Chi-square test was used to evaluate the relationship between baseline features and rate of positive PSMA PET/CT.

RESULTS

One hundred patients were enrolled. PSMA results were negative/positive in the prostate bed in 72 patients, pelvic nodal or extrapelvic metastatic disease were detected in 23 and 5 patients. Twenty-one patients underwent observation because of prior postoperative radiotherapy (RT)/treatment refusal. Fifty patients were treated with prostate bed SRT, 23 patients underwent SBRT to pelvic nodal disease, five patients were treated with SBRT to oligometastatic disease. One patient underwent ADT. NCCN high-risk features, stage > pT3 and ISUP score >3 reported a significantly higher rate of positive PSMA PET/CT after restaging (p = 0.01, p = 0.02, and p = 0.002). By quartiles of PSA, rate of positive PSMA PET/CT was 26.9% (>0.2; <0.29 ng/mL), 24% (>0.3; <0.37 ng/mL), 26.9% (>0.38; <0.51 ng/mL), and 34.7% (>0. 52; <0.98 ng/mL).

CONCLUSIONS

PSICHE trial constitute a useful platform to collect data within a clinical framework where modern imaging and metastasis-directed therapy are integrated.

MicroRNAs as biomarkers for early diagnosis, targeting and prognosis of prostate cancer

Globally, prostate cancer (PC) is leading cause of cancer-related mortality in men worldwide. Despite significant advances in the treatment and management of this disease, the cure rates for PC remains low, largely due to late detection. PC detection is mostly reliant on prostate-specific antigen (PSA) and digital rectal examination (DRE); however, due to the low positive predictive value of current diagnostics, there is an urgent need to identify new accurate biomarkers. Recent studies support the biological role of microRNAs (miRNAs) in the initiation and progression of PC, as well as their potential as novel biomarkers for patients' diagnosis, prognosis, and disease relapse. In the advanced stages, cancer-cell-derived small extracellular vesicles (SEVs) may constitute a significant part of circulating vesicles and cause detectable changes in the plasma vesicular miRNA profile. Recent computational model for the identification of miRNA biomarkers discussed. In addition, accumulating evidence indicates that miRNAs can be utilized to target PC cells. In this article, the current understanding of the role of microRNAs and exosomes in the pathogenesis and their significance in PC prognosis, early diagnosis, chemoresistance, and treatment are reviewed.

Therapeutic potential of targeting mirnas to prostate cancer tumors: using psma as an active target

Prostate cancer (PC) is a commonly diagnosed malignancy in men and is associated with high mortality rates. Current treatments for PC include surgery, chemotherapy, and radiation therapy. However, recent advances in targeted delivery systems have yielded promising new approaches to PC treatment. As PC epithelial cells express high levels of prostate-specific membrane antigen (PSMA) on the cell surface, new drug conjugates focused on PSMA targeting have been developed. microRNAs (miRNAs) are small noncoding RNAs that regulate posttranscriptional gene expression in cells and show excellent possibilities for use in developing new therapeutics for PC. PSMA-targeted therapies based on a miRNA payload and that selectively target PC cells enhances therapeutic efficacy without eliciting damage to normal surrounding tissue. This review discusses the rationale for utilizing miRNAs to target PSMA, revealing their potential in therapeutic approaches to PC treatment. Different delivery systems for miRNAs and challenges to miRNA therapy are also explored.

MicroRNAs as Potential Liquid Biopsy Biomarker for Patients with Castration-Resistant Prostate Cancer

Purpose

Patients and Methods

Results

Conclusion

Hsa-miR-186-5p regulates TGFβ signaling pathway through expression suppression of SMAD6 and SMAD7 genes in colorectal cancer

TGFβ signaling is a known pathway to be involved in colorectal cancer (CRC) progression and miRNAs play crucial roles by regulating different components of this pathway. Hence, finding the link between miRNAs and the pathway could be beneficial for CRC therapy. Array data indicated that miR-186-5p is a differentially expressed miRNA in colorectal Tumor/Normal tissues and bioinformatics tools predicted SMAD6/7 (inhibitory SMADs) as bona fide targets of this miRNA. Here, we intended to investigate the regulatory effect of the miR-186-5p expression on TGFβ signaling in CRC. Firstly, the miR-186-5p overexpression in HCT116 cells resulted in a significant reduction of SMAD6/7 expression, measured through RT-qPCR. Then, the direct interactions of miR-186-5p with SMAD6/7 3'UTRs were supported through dual luciferase assay. Furthermore, miR-186-5p overexpression suppressed proliferation, cell viability, and migration while, it increased apoptosis in CRC cells, assessed by cell cycle, MTT, scratch and Annexin V/PI apoptosis assays. Consistently, miR-186-5p overexpression resulted in reduced CyclinD1 protein using western blot, and also resulted in increased P21 and decreased c-Myc expression. Overall, these results introduced miR-186-5p as a cell cycle suppressor through downregulation of SMAD6/7 expression. Thus, miR-186-5p might be served as a novel tumor suppressive biomarker and therapeutic target in CRC treatment.

Long intergenic non-coding RNA 1939 eliminates proliferation and migration of human renal cell carcinoma (RCC) cells by down-regulation of miR-154

Renal carcinoma (RCC) is widely accepted as a malignant tumour of urinary system. Long intergenic non-coding RNA 1939 (LINC01939) is a novel lncRNA which was found to be down-regulated in RCC. Thus, we set out to explore the effect and regulation mechanism of LINC01939 in RCC. LINC01939 and miR-154 in RCC tissues and cell lines were detected using qRT-PCR assay. To examine cellular viability of ACHN and CAKI-1 cells, cell counting kit-8 (CCK-8) assay was exploited here. Flow cytometric analysis was conducted to examine apoptosis. Cell mobility was valued through wound healing assays. Western blotting was applied for examination of proteins related to proliferation, apoptosis, migration and Wnt/β-catenin/Notch. LINC01939 was down-regulated in RCC tissues. LINC01939 overexpression impeded proliferation and migration, and induced apoptosis. Further study found that the overexpression of LINC01939 strongly suppressed miR-154 expression. Then, the inhibiting effect of overexpressed LINC01939 on proliferation and mobility and the promoting role of LINC01939 in apoptosis were abolished by the combination of miR-154 mimic. Finally, we found that overexpressed LINC01939 inactivated Wnt/β-catenin and Notch through suppressing miR-154. Up-regulation of LINC01939 inhibited proliferation and migration of RCC cells by down-regulating miR-154.

Evaluation of MicroRNAs as Non-Invasive Diagnostic Markers in Urinary Cells from Patients with Suspected Prostate Cancer

Currently used tumor markers for early diagnosis of prostate cancer (PCa) are often lacking sufficient specificity and sensitivity. Therefore, the diagnostic potential of selected microRNAs in comparison to serum PSA levels and PSA density (PSAD) was explored. A panel of 12 PCa-associated microRNAs was quantified by qPCR in urinary sediments from 50 patients with suspected PCa undergoing prostate biopsy, whereupon PCa was detected in 26 patients. Receiver operating characteristic (ROC) curve analyses revealed a potential for non-invasive urine-based PCa detection for miR-16 (AUC = 0.744, p = 0.012; accuracy = 76%) and miR-195 (AUC = 0.729, p = 0.017; accuracy = 70%). While serum PSA showed an insufficient diagnostic value (AUC = 0.564, p = 0.656; accuracy = 50%) in the present cohort, PSAD displayed an adequate diagnostic performance (AUC = 0.708, p = 0.031; accuracy = 70%). Noteworthy, the combination of PSAD with the best candidates miR-16 and miR-195 either individually or simultaneously improved the diagnostic power (AUC = 0.801–0.849, p < 0.05; accuracy = 76–90%). In the sub-group of patients with PSA ≤ 10 ng/mL (n = 34), an inadequate diagnostic power of PSAD alone (AUC = 0.595, p = 0.524; accuracy = 68%) was markedly surpassed by miR-16 and miR-195 individually as well as by their combination with PSAD (AUC = 0.772–0.882, p < 0.05; accuracy = 74–85%). These findings further highlight the potential of urinary microRNAs as molecular markers with high clinical performance. Overall, these results need to be validated in a larger patient cohort.

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.

Targeting Transient Receptor Potential Channels by MicroRNAs Drives Tumor Development and Progression

Transient receptor potential (TRP) cation channel superfamily plays important roles in a variety of cellular processes such polymodal cellular sensing, adhesion, polarity, proliferation, differentiation and apoptosis. The expression of TRP channels is strictly regulated and their de-regulation can stimulate cancer development and progression.In human cancers, specific miRNAs are expressed in different tissues, and changes in the regulation of gene expression mediated by specific miRNAs have been associated with carcinogenesis. Several miRNAs/TRP channel pairs have been reported to play an important role in tumor biology. Thus, the TRPM1 gene regulates melanocyte/melanoma behaviour via TRPM1 and microRNA-211 transcripts. Both miR-211 and TRPM1 proteins are regulated through microphthalmia-associated transcription factor (MIFT) and the expression of miR-211 is decreased during melanoma progression. Melanocyte phenotype and melanoma behaviour strictly depend on dual TRPM1 activity, with loss of TRPM1 protein promoting melanoma aggressiveness and miR-211 expression supporting tumour suppressor. TRPM3 plays a major role in the development and progression of human clear cell renal cell carcinoma (ccRCC) with von Hippel-Lindau (VHL) loss. TRPM3, a direct target of miR-204, is enhanced in ccRCC with inactivated or deleted VHL. Loss of VHL inhibits miR-204 expression that lead to increased oncogenic autophagy. Therefore, the understanding of specific TRP channels/miRNAs molecular pathways in distinct tumors could provide a clinical rationale for target therapy in cancer.

Suppression of α-methylacyl-coenzyme A racemase by miR200c inhibits prostate adenocarcinoma cell proliferation and migration

Overexpression of α-methylacyl-coenzyme A racemase (AMACR/P504S) is a major abnormality that has been observed in prostate cancer, whereas microRNA (miRNA/miR) 200c, is downregulated. The aim of the present study was to explore whether miR200c was able to exert any regulatory effects on AMACR. To meet this aim, bioinformatics analysis was performed to identify potential binding sites for miR200c in the 3′-untranslated region (3′-UTR) of AMACR. Recombinant adenoviral and dual reporter gene assays were designed to examine the binding of miR200c to the potential seed sequences in the AMACR 3′-UTR. Conventional reverse transcription (RT)-PCR, RT-quantitative (q)PCR and western blotting were also used to examine the regulatory effects of miR200c on AMACR at the mRNA and protein levels. Furthermore, Cell Counting Kit-8, wound healing and Transwell assays were performed to investigate the biological effects of miR200c-AMACR deregulation on prostate cancer cell proliferation, migration and invasion. It was revealed that miR200c post-transcriptionally suppressed AMACR expression by interacting with the 90–97 nucleotide sequence of the AMACR mRNA 3′-UTR. Artificial overexpression of miR200c significantly downregulated the mRNA and protein levels of AMACR in DU145 and PC-3 prostate cancer cells. Knockdown of AMACR by RNA interference, or overexpression of miR200c by recombinant adenoviral Ad-miR200c, inhibited prostate cancer cell proliferation, migration and invasiveness. Taken together, the results of the present study revealed that miR200c may suppress the AMACR expression level post-transcriptionally. The results also indicate that perturbation of the miR200c-AMACR regulatory mechanism may be involved in prostate carcinogenesis and that this may be exploited in future therapeutic approaches to prostate cancer.

Neferine inhibits MDA-MB-231 cells growth and metastasis by regulating miR-374a/FGFR-2

BACKGROUND

Neferine (NEF) is a major bisbenzylisoquinline alkaloid mainly exists in the seed embryo of Nelumbo nucifera (Gaertn.) that possesses anti-tumor effects. Our study designed to check the effect of NEF on breast cancer MDA-MB-231 cells and further explore the potential mechanism.

METHODS

MDA-MB-231 cells were administrated with various dosages of NEF for 24 h after which cell viability was measured. The effects of NEF on cell proliferation, apoptosis, migration and invasion were assessed by BrdU staining, flow cytometry assay and Transwell assay. Western blot was utilized to assess the accumulation of proteins related with proliferation, apoptosis, metastasis, PI3K/AKT and MEK/ERK pathways.

RESULTS

Viability was efficiently reduced by NEF in a dose-dependent manner. NEF (8 μM) significantly suppressed cell proliferation, migration and invasion but enhanced apoptosis in MDA-MB-213 cells. Interestingly, NEF suppressed miR-374a expression and miR-374a mediated the inhibitory effect of NEF. Moreover, miR-374a positively regulated FGFR-2 expression and FGFR-2 overexpression impeded the effect of NEF on MDA-MB-213 cells. FGFR-2 overexpression abolished the suppressive effect of NEF on PI3K/AKT and MEK/ERK pathways.

CONCLUSION

We found that NEF possessed the anti-growth and anti-metastasis effect on MDA-MB-231 cells through regulating miR-374a/FGFR-2, which might provide new insight for breast cancer management.

How hsa-miR-495 performed in the tumorigenesis of pancreatic adenocarcinoma by bioinformatics analysis

INTRODUCTION

Pancreatic adenocarcinoma (PAAD) is one of the most fatal cancers in the world for early metastasis, extensive invasion, and poor prognosis with a 5-year survival rate less than 5%. However, the underlying mechanisms are poorly understood. Therefore, it is urgent to explore molecular markers for early diagnosis or therapy target to improve the outcome of PAAD.

METHODS

We retrieved transcriptome data as well as clinical information from patients with PAAD in The Cancer Genome Altas (TCGA) database. Survival time associated microRNAs (miRNAs) and messenger RNAs (mRNAs) were initially identified, followed by enrichment analysis (Gene Ontology [GO] and pathway). The relationship between survival time associated miRNAs-mRNAs was also investigated to discover putative transcriptional control mechanisms of PAAD. Finally, by consulting the literature and retrieving the database, we found that hsa-miR-495 might have played an important role in PAAD.

RESULTS

In total, 146 miRNAs from 378 miRNAs and 580 mRNA from 17 100 mRNA, including 328 risk mRNA and 252 protective mRNA, were found to be associated with the survival time of PAAD. Eight hundred eighty-eight mRNA-miRNA pairs were related to the survival time of PAAD, involving in 755 mRNAs and 35 miRNAs. We chose 13 miRNAs predicted by target gene in the miRanda database for further research. Among these 13 miRNAs, hsa-miR-495 was identified as a good biomarker. Through GO and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, the significantly enriched pathways involved in focal adhesion, Staphylococcus aureus infection, and Intestinal immune network for immunoglobulin A production. And four target genes and 87 pathways of the hsa-miR-495 were enriched in PAAD. Interestingly, we found hsa-miR-495 with a low expression having a poor overall survival and significantly different recurrence rate within 5 years.

CONCLUSION

Hsa-miR-495 and its target genes may serve as a prognostic and predictive marker in PAAD. Further research on the function of the hsa-miR-495 and its target genes in the KEGG pathway may provide references for treatment of PAAD.

Downregulation of miR‑186 promotes the proliferation and drug resistance of glioblastoma cells by targeting Twist1

Temozolomide (TMZ) is widely used as a chemotherapeutic agent in the treatment of glioma; however, the development of drug resistance remains a major obstacle in the effective treatment of glioblastoma. Increasing evidence has indicated that microRNAs (miRs) are involved in the drug resistance of glioma; however, the role of miR‑186‑5p in the TMZ resistance of glioblastoma remains unknown. In the present study, the role of miR‑186‑5p in the resistance of glioblastoma to TMZ was investigated. mRNA and protein expression levels were detected via reverse transcription‑quantitative PCR and western blot analysis, respectively. It was determined that miR‑186‑5p was significantly downregulated in glioblastoma tissues and cell lines. Additionally, the expression of miR‑186‑5p was decreased, whereas that of Twist1 was upregulated during the development of drug resistance in glioma cells. The introduction of miR‑186 into glioblastoma cells via transfection decreased the proliferation and TMZ resistance of glioblastoma cells, as determined via 5‑ethynyl‑2'‑deoxyuridine and Cell Counting Kit‑8 assays, whereas the inhibition of miR‑186‑5p induced opposing effects. Furthermore, luciferase reporter and expression rescue assays revealed that miR‑186‑5p bound to the 3'‑untranslated region of Twist‑related protein 1 (Twist1). In conclusion, the present study demonstrated that downregulation of miR‑186‑5p may contribute to the proliferation and drug resistance of glioblastoma cells via the regulation of Twist1 expression. These results suggested that miR‑186‑5p may be a novel therapeutic target in the treatment of glioblastoma.

miR-93-5p may be an important oncogene in prostate cancer by bioinformatics analysis

INTRODUCTION

Prostate adenocarcinoma is one of the most prevalent causes of cancer-related deaths in males worldwide. However, the underlying mechanisms remain poorly understood. Hence, it is important to identify specific and effective therapeutic targets, to be able to determine appropriate therapy and management. So, this study aimed to predict that miR-93-5p is an important oncogene in prostate cancer by bioinformatics analysis.

METHODS

In this study, initially we identified differentially expressed genes (DEGs) and differently expressed miRNAs (DEMs) in the The Cancer Genome Atlas (TCGA) database, performed Gene Ontology (GO) and pathway enrichment analysis, then investigated the relationship between DEGs and DEMs, and finally through consulting the literature and retrieving the database, we found that miR-93-5p may play a major role in prostate cancer, so we predicted the expression and survival of miR-93-5p and its isomers by bioinformatics analysis, meanwhile, evaluated the function of miR-93-5p in vitro.

RESULTS

In total, 104 DEMs were differently expressed between prostate cancer and normal samples, including 56 downregulated ones and 48 upregulated ones; miR-93-5p (upregulated) was identified as a good biomarker. And 1904 DEGs were retrieved, including 794 downregulated ones and 1110 upregulated ones. We also obtained 1254 DEGs of the DEMs. In GO and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, the significantly enriched pathways involved pathway in focal adhesion, vascular smooth muscle contraction, and regulation of actin cytoskeleton. By the KEGG pathway, we got 16 target genes and 92 pathways of the miR-93-5p in prostate cancer. We also found that the miR-93-5p and its isomers can express in prostate cancer, and which with a high expression had a poor overall survival and a significant difference recurrence rate within 5 years. Further in vitro verification results demonstrated that the low expression of miR-93-5p can inhibit cell proliferation, migration, invasion, change cell cycle, and promote early apoptosis of PC-3 cells.

CONCLUSION

The miR-93-5p and its target genes were used to define important molecular targets that could serve as a prognostic and predictive marker in the treatment of prostate cancer. Further research on the function of the miR-93-5p and its target genes in the KEGG pathway could provide references for the treatment of prostate cancer.

Micro-RNA-186-5p inhibition attenuates proliferation, anchorage independent growth and invasion in metastatic prostate cancer cells

Background

Dysregulation of microRNA (miRNA) expression is associated with hallmarks of aggressive tumor phenotypes, e.g., enhanced cell growth, proliferation, invasion, and anchorage independent growth in prostate cancer (PCa).

Methods

Serum-based miRNA profiling involved 15 men diagnosed with non-metastatic (stage I, III) and metastatic (stage IV) PCa and five age-matched disease-free men using miRNA arrays with select targets confirmed by quantitative real-time PCR (qRT-PCR). The effect of miR-186-5p inhibition or ectopic expression on cellular behavior of PCa cells (i.e., PC-3, MDA-PCa-2b, and LNCaP) involved the use bromodeoxyuridine (BrdU) incorporation, invasion, and colony formation assays. Assessment of the impact of miR-186-5p inhibition or overexpression on selected targets entailed microarray analysis, qRT-PCR, and/or western blots. Statistical evaluation used the modified t-test and ANOVA analysis.

Results

MiR-186-5p was upregulated in serum from PCa patients and metastatic PCa cell lines (i.e., PC-3, MDA-PCa-2b, LNCaP) compared to serum from disease-free individuals or a normal prostate epithelial cell line (RWPE1), respectively. Inhibition of miR-186-5p reduced cell proliferation, invasion, and anchorage-independent growth of PC-3 and/or MDA-PCa-2b PCa cells. AKAP12, a tumor suppressor target of miR-186-5p, was upregulated in PC-3 and MDA-PCa-2b cells transfected with a miR-186-5p inhibitor. Conversely, ectopic miR-186-5p expression in HEK 293 T cells decreased AKAP12 expression by 30%. Both pAKT and β-catenin levels were down-regulated in miR-186-5p inhibited PCa cells.

Conclusions

Our findings suggest miR-186-5p plays an oncogenic role in PCa. Inhibition of miR-186-5p reduced PCa cell proliferation and invasion as well as increased AKAP12 expression. Future studies should explore whether miR-186-5p may serve as a candidate prognostic indicator and a therapeutic target for the treatment of aggressive prostate cancer.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4258-0) contains supplementary material, which is available to authorized users.

miR-204 suppresses the development and progression of human glioblastoma by targeting ATF2

In human cancers, miRNAs are important regulators of multiple cellular processes, and aberrant miRNA expression has been observed, and their alterations contribute to multiple cancer development and progression. Till now, little has been known about the role of miR-204 in human glioblastoma (GBM). In the present study, we used in-vitro assays to investigate the mechanisms of miR-204 in GBM cell lines and 60 cases of GBM tissues. Here, we found that miR-204 expression is downregulated in both GBM cell lines A172, U87 and U251 cells and GBM tissues as compared with NHA cells and normal tissues (all p<0.001). In addition, the ectopic expression of miR-204 suppressed A172 and U87 cell proliferation, migration and invasion. Meanwhile, miR-204 over-expression extremely inhibited the protein expression of ATF2. Notably, the enforced expression of ATF2 in A172 and U87 cells with the over-expression of miR-204 attenuated the inhibitory effects of miR-204 on proliferation, migration and invasion. In conclusion, our findings suggest that miR-204 suppressed cell proliferation, migration and invasion through inhibition of ATF2, thus, miR-204 may function as a useful drug target in the treatment and diagnosis of GBM.

Arresting of miR-186 and releasing of H19 by DDX43 facilitate tumorigenesis and CML progression

Cancer-testis (CT) antigens, rarely in normal tissues except testis, are expressed in many tumor types. In recent years, DDX43 has been shown to be expressed in several malignancies. However, the role of DDX43 during tumorigenesis is not well established. In the present study, we explored the function of DDX43 in chronic myeloid leukemia (CML). We found that DDX43 overexpression in CML cell lines enhanced survival and colony formation, inhibited cell apoptosis, promoted tumorigenesis, and CML progression. In contrast, silencing of DDX43 inhibited cell survival and tumorigenesis. Upregulated H19 and downregulated miR-186 were identified in DDX43-transfected cells. Furthermore, we demonstrated that miR-186 targeted DDX43, and overexpressed miR-186 increased apoptosis and decreased cell survival. We also showed that DDX43 regulated the expression of H19 through demethylation and silencing H19 inhibited cell survival. Taken together, these results indicate that DDX43 provides critical support to the progression of CML by enhancing cell survival, colony formation, and inhibiting cell apoptosis, thereby implicating DDX43 as a potential therapeutic target in CML.

miR-186 affects the proliferation, invasion and migration of human gastric cancer by inhibition of Twist1

Recent evidence shows that miRNAs are dysregulated in a variety of cancers including gastric cancer (GC), and emerging as key oncogenes or tumor suppressors. In this study, qRT-PCR was used to analyze the expression of miR-186 in GC tissues and adjacent non-cancerous tissues, and then more in-vitro experiments were used to investigate the role of miR-186 in GC cells. Here, we identified miR-186 was generally down-regulated in GC tissues; however, Twist1 was generally up-regulated in GC tissues. Moreover, miR-186 and Twist1 were associated with larger tumor size and advanced clinical stage of GC. In-vitro experiments demonstrated that ectopic overexpression of miR-186 inhibited GC cell proliferation, invasion and migration; however, inhibited expression of miR-186 enhanced cell proliferation, invasion and migration. Furthermore, the luciferase reporter assay demonstrated Twist1 as a direct target of miR-186. Finally, over-expression of Twist1 abrogated inhibitory impact of miR-186 on cell proliferation, invasion and migration. In conclusion, miR-186 affects the proliferation, invasion and migration of human gastric cancer by inhibition of Twist1, and could be a tumor suppressor in GC development. Thus, miR-186 may be served as a candidate prognostic biomarker and target for new therapies in human gastric cancer.

Targeting of short TRPM8 isoforms induces 4TM-TRPM8-dependent apoptosis in prostate cancer cells

Since its cloning a decade ago, TRPM8 channel has emerged as a promising prognostic marker and a putative therapeutic target in prostate cancer (PCa). However, recent studies have brought to light the complexity of TRPM8 isoforms in PCa. Consequently, the respective role of each TRPM8 isoform needs to be deciphered prior to considering TRPM8 as an attractive therapeutic target. Full-length (6 transmembrane (TM)-domain) TRPM8 channel is overexpressed in early PCa and repressed in advanced prostate tumors whereas the localization of the truncated, 4TM-TRPM8 channel (4 transmembrane (TM)-domain), in the membranes of endoplasmic reticulum (ER) is independent of the pathogenic status of epithelial cells. In the same line, expression of non-channel cytoplasmic small TRPM8 isoforms (namely sM8) is conserved in cancer cells. In this study, we identify sM8s as putative regulator of PCa cell death. Indeed, suppression of sM8 isoforms was found to induce concomitantly ER stress, oxidative stress, p21 expression and apoptosis in human epithelial prostate cancer cells. We furthermore demonstrate that induction of such mechanisms required the activity of 4TM-TRPM8 channels at the ER-mitochondria junction. Our study thus suggests that targeting sM8 could be an appropriate strategy to fight prostate cancer.

Circulating mRNAs and miRNAs as candidate markers for the diagnosis and prognosis of prostate cancer

Circulating nucleic acids are found in free form in body fluids and may serve as minimally invasive tools for cancer diagnosis and prognosis. Only a few studies have investigated the potential application of circulating mRNAs and microRNAs (miRNAs) in prostate cancer (PCa). The Cancer Genome Atlas (TCGA) database was used for an in silico analysis to identify circulating mRNA and miRNA as potential markers of PCa. A total of 2,267 genes and 49 miRNAs were differentially expressed between normal and tumor samples. The prediction analyses of target genes and integrative analysis of mRNA and miRNA expression revealed eleven genes and eight miRNAs which were validated by RT-qPCR in plasma samples from 102 untreated PCa patients and 50 cancer-free individuals. Two genes, OR51E2 and SIM2, and two miRNAs, miR-200c and miR-200b, showed significant association with PCa. Expression levels of these transcripts distinguished PCa patients from controls (67% sensitivity and 75% specificity). PCa patients and controls with prostate-specific antigen (PSA) ≤ 4.0 ng/mL were discriminated based on OR51E2 and SIM2 expression levels. The miR-200c expression showed association with Gleason score and miR-200b, with bone metastasis, bilateral tumor, and PSA > 10.0 ng/mL. The combination of circulating mRNA and miRNA was useful for the diagnosis and prognosis of PCa.

Induction of alpha-methylacyl-CoA racemase by miR-138 via up-regulation of β-catenin in prostate cancer cells

PURPOSE

Alpha-methylacyl-CoA racemase (AMACR) is highly overexpressed in prostate cancer (PCa) and its transcriptional regulators include various transcription factors and CTNNB1/β-catenin. Our previous findings suggested a post-transcriptional regulation by the tumor-suppressive microRNA miR-138 in PCa. Thus, the aim of this study was to demonstrate the direct interaction of miR-138 with the 3'-UTR of AMACR. Furthermore, the influence of miR-138 on the expression of AMACR and selected AMACR regulators was investigated in PCa cells.

METHODS

Using DU-145, PC-3, and LNCaP PCa cells, the effect of exogenous miR-138 on AMACR and selected AMACR regulators was determined by quantitative PCR and Western blot. Luciferase reporter assays were used to verify target and promoter interaction.

RESULTS

Using a luciferase reporter assay a direct interaction of miR-138 with the AMACR-3'-UTR was confirmed. Surprisingly, AMACR expression was up-regulated by up to 125% by exogenous miR-138 in PCa cells. The lack of any miR-138 binding sites within the AMACR promoter suggested an indirect mechanism of up-regulation. Therefore, the effect of miR-138 on selected AMACR regulators including CTNNB1/β-catenin, RELA, SMAD4, SP1, and TCF4 was evaluated. MiR-138 solely evoked an up-regulation of CTNNB1 mRNA expression and β-catenin protein levels by up to 75%. Further in silico analysis revealed a binding site for miR-138 within the CTNNB1 promoter. MiR-138 could enhance the activity of the CTNNB1 promoter, which in turn could contribute to the observed AMACR up-regulation.

CONCLUSIONS

The present findings suggest that miR-138 can indirectly up-regulate AMACR via transcriptional induction of CTNNB1, at least in vitro in PCa cells.

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.

miRNA-186 inhibits prostate cancer cell proliferation and tumor growth by targeting YY1 and CDK6

microRNAs (miRNAs) are known to be important in tumor initiation and progression. Recent studies have demonstrated that miR-186 is critical in several types of cancer, including human non-small cell lung cancer, bladder cancer and pancreatic ductal adenocarcinoma. However, the functions of miR-186 in prostate cancer (PCa) are still unclear. In the present study, downregulation of miR-186 in PCa cells was detected when compared with the normal prostate cell line. When miR-186 overexpressed in PCa cells, cell proliferation in vitro was evidently inhibited as shown using cell counting kit-8 assays and cell-cycle analysis, and tumor growth in vivo was decreased as shown by tumor growth assays in nude mice. Furthermore, through bioinformatics prediction and biochemical analyses, Yin Yang 1 (YY1) and cyclin-dependent kinase 6 (CDK6) have been proven to act as direct targets of miR-186. These results indicate that miR-186 is a negative regulator in PCa by inhibiting PCa cell proliferation via targeting YY1 and CDK6.

Computational Analysis of Specific MicroRNA Biomarkers for Noninvasive Early Cancer Detection

Cancer is a complex disease residing in various tissues of human body, accompanied with many abnormalities and mutations in genomes, transcriptome, and epigenome. Early detection plays a crucial role in extending survival time of all major cancer types. Recent advances in microarray and sequencing techniques have given more support to identifying effective biomarkers for early detection of cancer. MicroRNAs (miRNAs) are more and more frequently used as candidates for biomarkers in cancer related studies due to their regulation of target gene expression. In this paper, the comparative analysis is used to discover miRNA expression patterns in cancer versus normal samples on early stage of eight prevalent cancer types. Our work focuses on the specific miRNAs biomarkers identification and function analysis. Several identified miRNA biomarkers in this paper are matched well with those reported in existing researches, and most of them could serve as potential candidate indicators for clinical early diagnosis applications.

Clinical Validation of a Serum Protein Panel (FLNA, FLNB and KRT19) for Diagnosis of Prostate Cancer

This study reports on the development of a novel serum protein panel of three prostate cancer biomarkers, Filamin A, Filamin B and Keratin-19 (FLNA, FLNB and KRT19) using multivariate models for disease screening and prognosis. ELISA and IPMRM (LC-MS/MS) based assays were developed and analytically validated by quantitative measurements of the biomarkers in serum. Retrospectively collected and clinically annotated serum samples with PSA values and Gleason scores were analyzed from subjects who underwent prostate biopsy, and showed no evidence of cancer with or without indication of prostatic hyperplasia, or had a definitive pathology diagnosis of prostatic adenocarcinoma. Probit linear regression models were used to combine the analytes into score functions to address the following clinical questions: does the biomarker test augment PSA for population screening? Can aggressive disease be differentiated from lower risk disease, and can the panel discriminate between prostate cancer and benign prostate hyperplasia? Modelling of the data showed that the new prostate biomarkers and PSA in combination were better than PSA alone in identifying prostate cancer, improved the prediction of high and low risk disease, and improved prediction of cancer versus benign prostate hyperplasia.

Upregulation of kazrin F by miR-186 suppresses apoptosis but promotes epithelial-mesenchymal transition to contribute to malignancy in human cervical cancer cells

Objective

Previous studies have identified that kazrin is a constituent of desmosome and influences intercellular adhesion, growing development and morphology. We previously cloned another new isoform, kazrin F and found that it has anti-apoptotic effects on human glioma cell line. To further explore whether kazrin F is involved in tumorigenesis, we investigated its expression and role in cervical cancer (CC) cells.

Methods

The role of kazrin F and miR-186 in CC was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, colony formation, transwell, and apoptosis assays. Using enhanced green fluorescent protein (EGFP) reporter assays, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis, we identified kazrin F post-transcriptional regulation by miR-186.

Results

We demonstrate that kazrin F is highly expressed in CC tissues compared with the adjacent noncancerous tissues and promotes cell proliferation, colony formation, migration and invasion in HeLa and C33A cells by suppressing apoptosis and facilitating epithelial-to-mesenchymal transition (EMT). Furthermore, miR-186 was confirmed as a regulator of kazrin F dysregulation. An EGFP reporter assay proved that miR-186 directly targets the 3’-untranslated region (3’UTR) of kazrin F and downregulates its expression, and miR-186 expression showed an inverse correlation with kazrin F levels in CC tissues. In addition, overexpression of miR-186 suppressed the malignant behaviors of CC cells. The ectopic expression of kazrin F rescued the inhibitory effects of miR-186.

Conclusions

Our findings indicate that the upregulation of kazrin F due to downregulated miR-186 levels contributes to malignancy, and highlight the significance of kazrin F in CC tumorigenesis.

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

Introduction

Diagnosis of prostate cancer (PCa) is based on prostate biopsy that is performed when prostate specific antigen (PSA) is persistently altered over time and/or abnormal digital rectal examination is found. Serum PSA levels increase in both PCa and benign prostatic hyperplasia, leading to an increased number of unnecessary biopsies. There is an urgent need to unravel PCa-specific molecular signatures.

Patients and methods

This study aimed at characterizing a panel of circulating micro RNAs (miRNAs) that could distinguish PCa from benign prostatic hyperplasia in a population of age-matched patients with increased PSA levels. Both miRNAs targeting genes involved in PCa onset and miRNAs whose role in PCa has been highlighted in other studies were included. For this purpose, let-7c, let-7e, let-7i, miR-26a-5p, miR-26b-5p, miR-24-3p, miR-23b-3p, miR-27-b-3p, miR-106a-5p, miR-20b-5p, miR-18b-5p, miR-19b-2-5p, miR-363-3p, miR-497, miR-195, miR-25-3p, miR-30c-5p, miR-622, miR-874-3p, miR-346 and miR-940 were assayed through real-time PCR in 64 patients with PCa and compared with 60 patients with benign prostatic hyperplasia. The ability of miRNAs to predict the stage of disease was also analyzed.

Results

Let-7c, let-7e, let-7i, miR-26a-5p, miR-26b-5p, miR-18b-5p and miR-25-3p were able to discriminate patients with PCa from those harboring benign prostatic hyperplasia, both presenting altered PSA levels (>3 ng/mL). MiR-25-3p and miR-18b-5p showed the highest sensitivity and specificity to predict PCa, respectively. The combination of these two miRNAs improved the overall sensitivity. A correlation between pathological Gleason score and miRNA expression levels was reported; miR-363-3p, miR-26a-5p, miR-26b-5p, miR-106a-5p, miR-18b-5p, miR-25-3p and let-7i decreased in expression concomitantly with an increase in malignancy.

Conclusion

This study confirms serum miRNAs to be reliable candidates for the development of minimally invasive biomarkers for the diagnosis and prognosis of PCa, particularly in those cases where PSA acts as a flawed marker.

Recent scenario of microRNA as diagnostic and prognostic biomarkers of prostate cancer

Prostate cancer (CaP) is a leading cause of cancer death and displays a broad range of clinical behavior from relatively indolent to aggressive metastatic disease. Due to the alteration and incomplete characterization of the CaP genomic markers, the quest for novel cellular metabolic regulatory molecules like micro RNA (miRNA) as a biomarker could be considered for the prognosis and treatment of CaP in future. In this article, we review the existing literature pertaining to CaP. Study provides a comprehensive miRNA profile expressed in CaP. Beside the miRNA expressed in the tumor tissue, circulating miRNAs have been found highly stable and are both detectable and quantifiable in a range of accessible bio fluids; therefore, miRNA has the potential to be useful diagnostic, prognostic and predictive biomarker. Along with being an important molecule in modulation of CaP progression, the miRNA have certain limitations such as lack of stable expression of multiple target genes and often disrupt entire signaling networks of cellular metabolic pathways. We conclude that: The alteration of miRNA and their role played in cellular regulatory networks would be the next target of basic research in CaP. The miRNAs identified may be validated and modeled to understand their role in CaP, using bioinformatics. There is an immediate unmet need in the translational approach of identified miRNAs. The characterization of miRNAs involved in CaP is still incomplete: adequate validation studies are required to corroborate current results.

MiR-26a and miR-138 block the G1/S transition by targeting the cell cycle regulating network in prostate cancer cells

PURPOSE

The tumor-suppressive microRNAs miR-26a and miR-138 are significantly down-regulated in prostate cancer (PCa) and have been identified as direct regulators of enhancer of zeste homolog 2 (EZH2), which is a known oncogene in PCa. In the present study, the influence of miR-26a and miR-138 on EZH2 and cellular function including the impact on the cell cycle regulating network was evaluated in PCa cells.

METHODS

PC-3 and DU-145 PCa cells were transfected with 100 nM of miRNA mimics, siRNA against EZH2 (siR-EZH2) or control constructs for 4 h. Analyses of gene expression and cellular function were conducted 48 h after transfection.

RESULTS

Both miRNAs influenced the EZH2 expression and activity only marginally, whereas siR-EZH2 led to a notable decrease of the EZH2 expression and activity. Both miRNAs inhibited short- and/or long-term proliferation of PCa cells but showed no effect on viability and apoptosis. In PC-3 cells, miR-26a and miR-138 caused a significant surplus of cells in the G0/G1 phase of 6 and 12 %, respectively, thus blocking the G1/S-phase transition. Treatment with siR-EZH2 was without substantial influence on cellular function and cell cycle. Therefore, alternative target genes involved in cell cycle regulation were identified in silico. MiR-26a significantly diminished the expression of its targets CCNE1, CCNE2 and CDK6, whereas CCND1, CCND3 and CDK6 were suppressed by their regulator miR-138.

CONCLUSIONS

The present findings suggest an anti-proliferative role for miR-26a and miR-138 in PCa by blocking the G1/S-phase transition independent of EZH2 but via a concerted inhibition of crucial cell cycle regulators.

miR-186 inhibits cell proliferation of prostate cancer by targeting GOLPH3

Prostate cancer is one of the leading causes of cancer deaths among men, many miRNAs have been demonstrated to play critical role in the progression of prostate cancer, miR-186 suppresses the progression of many tumors, such as bladder cancer and glioma. Previous study shows miR-186 is downregulated in prostate cancer tissues, and is a good prognosis for prostate cancer patients. In this study, we found miR-186 was downregulated in prostate cancer cells and tissues, overexpression of miR-186 inhibited cell proliferation and tumorigenesis in vitro determined by MTT assay, colony formation assay and soft agar growth assay, whereas knockdown of miR-186 reduced these effects. Cell cycle analysis found miR-186 overexpression arrested cell cycle in G0/G1 phase, and reduced p21 and p27 levels, and enhanced Cyclin D1 and the phosphorylation of Rb levels, suggesting miR-186 blocked G1/S transition. A novel oncogene Golgi phhosphoprotein 3 (GOLPH3) was the target of miR-186, miR-186 bound to the 3'UTR of GOLPH3. Moreover, miR-186 was negatively correlated with GOLPH3 in prostate cancer tissues. In conclusion, our study suggested miR-186 inhibited cell proliferation through targeting oncogene GOLPH3.

MicroRNA-186 suppresses cell proliferation and metastasis through targeting MAP3K2 in non-small cell lung cancer

MicroRNAs are a class of small endogenous non-coding RNAs that play crucial roles in the initiation and progression of human cancers. miR-186 was found decreased in various human malignancies and function as a tumor suppressor. However, the regulating mechanism of miR-186 in growth and metastasis of human non-small cell lung cancer (NSCLC) is still poorly understood. We investigated the role of miR-186 in the growth and metastasis of human NSCLC. In the present study, we found that miR-186 was significantly decreased in lung cancer tissues and cells. Furthermore, overexpression of miR-186 suppressed lung cancer cell proliferation, migration and invasion, and induced cell apoptosis. Moreover, we found that confirmed mitogen-activated protein kinase kinase kinase 2 (MAP3K2) protein was increased in lung cancer tissues and confirmed that MAP3K2 is a target gene of miR-186. In addition, knockdown of MAP3K2 by RNA interference inhibited lung cancer cell proliferation, migration and invasion, and promoted cell apoptosis in vitro. Furthermore, we observed tthat the overexpression of MAP3K2 partially reversed the inhibitory effect of miR-186 on the proliferation and metastasis of A549 and HCC827 cell lines. Taken together, our data indicated that miR-186 regulates lung cancer growth and metastasis through suppressing MAP3K2 expression, at least partly. Therefore, miR-186-MAP3K2 may represent a new and useful potential clinical treatment and diagnosis target for NSCLC.

Loss of miR-26a-5p promotes proliferation, migration, and invasion in prostate cancer through negatively regulating SERBP1

The biological role of miR-26a involved in the carcinogenesis of prostate cancer (PC) has been controversial. Besides, the underlying mechanism by which miR-26a plays a role in PC has been unclear. To investigate the role of miR-26a-5p in the PC, miR-26a-5p was detected and statistically analyzed in clinical PC tissues and a panel of PC cell lines. Using bioinformatics analysis, we found that serpine1 messenger RNA (mRNA) binding protein 1 (SERBP1) was a potential downstream target of miR-26a-5p. Using luciferase reporter and western blot, we identified that miR-26a-5p negatively regulated SERBP1 on the PC cell line level. It was confirmed that miR-26a-5p was markedly downregulated in PC tissues compared with normal controls whose reduced expression was significantly associated with metastasis and poor overall prognosis and found that miR-26a-5p was able to prevent proliferation and motility of PC cells in vitro. Additionally, SERBP1 was identified as a downstream target of miR-26a-5p. Moreover, it was observed that SERBP1 was markedly upregulated in prostate cancer tissues and was significantly associated with tissue metastasis and Gleason score. Taken together, our results for the first time demonstrate that the loss of miR-26a-5p promotes proliferation, migration, and invasion through targeting SERBP1 in PC, supporting the tumor-suppressing role of miR-26a-5p in PC.

Assessing blood platelets as RNA biomarker source for prostate cancer

CONTEXT

Blood platelets may offer as RNA biomarker source for cancer as recently described for an oncogenic transcript in glioma patients and for PCA3 in prostate cancer (PCa) patients.

OBJECTIVE

Here, we elaborated on this aspect for PCa.

MATERIALS AND METHODS

PCA3 and other PCa-associated RNA markers were measured in platelets of PCa patients (cases) and healthy subjects (controls) in comparison to PCa cell lines by relative quantitative RT-PCR.

RESULTS

The RNA markers displayed heterogeneous expression patterns in cell lines and platelets, however, without significant differences between cases and controls.

DISCUSSION AND CONCLUSION

The data do not support platelets as a profitable RNA source for early detection of PCa. Nonetheless, certain PCa-derived RNA markers in platelets may merit further investigation as potential prognostic biomarkers for PCa.

MiR-374a suppresses lung adenocarcinoma cell proliferation and invasion by targeting TGFA gene expression

Aberrant expression of miR-374a has been reported in several types of human cancers, including lung cancer. However, the functional significance and molecular mechanisms underlying the role of miR-374a in lung cancer remain largely unknown. We found that the expression of miR-374a was significantly downregulated in lung adenocarcinoma tissues compared to adjacent normal lung tissues in samples included in The Cancer Genome Atlas. Functional studies revealed that overexpression of miR-374a led to inhibition of lung adenocarcinoma cell proliferation, migration and invasion and that miR-374a negatively regulated transforming growth factor-alpha (TGFA) gene expression by directly targeting the 3'-UTR of TGFA mRNA. Treating lung adenocarcinoma cells with TGF-α neutralizing antibody resulted in suppression of cell proliferation and invasion, which mimicked the action of miR-374a. Additionally, TGFA gene expression was significantly higher in tumor tissues compared to adjacent normal tissue and high TGFA gene expression strongly correlated with poor survival in patients with lung adenocarcinoma. Taken together, our studies suggest that miR-374a suppresses lung adenocarcinoma cell proliferation and invasion via targeting TGFA gene expression. Our findings may provide novel treatment strategies for lung adenocarcinoma patients.

miR-186 inhibits cell proliferation in multiple myeloma by repressing Jagged1

MicroRNAs (miRNAs) are small, noncoding ribonucleic acids that regulate gene expression by targeting mRNAs for translational repression and degradation. Accumulating experimental evidence supports a causal role of miRNAs in hematology tumorigenesis. However, the specific functions of miRNAs in the pathogenesis of multiple myeloma (MM) remain to be established. In this study, we demonstrated that miR-186 is commonly downregulated in MM cell lines and patient MM cells. Ectopic expression of miR-186 significantly inhibited cell growth, both in vitro and in vivo, and induced cell cycle G0/G1 arrest. Furthermore, miR-186 induced downregulation of Jagged1 protein expression by directly targeting its 3'-untranslated region (3'-UTR). Conversely, overexpression of Jagged1 rescued cells from miR-186-induced growth inhibition. Our collective results clearly indicate that miR-186 functions as a tumor suppressor in MM, supporting its potential as a therapeutic target for the disease.

Microtargeting cancer metabolism: opening new therapeutic windows based on lipid metabolism

Metabolic reprogramming has emerged as a hallmark of cancer. MicroRNAs are noncoding RNAs that posttranscriptionally repress the expression of target mRNAs implicated in multiple physiological processes, including apoptosis, differentiation, and cancer. MicroRNAs can affect entire biological pathways, making them good candidates for therapeutic intervention compared with classical single target approaches. Moreover, microRNAs may become more relevant in the fine-tuning adaptation to stress situations, such as oncogenic events, hypoxia, nutrient deprivation, and oxidative stress. Furthermore, artificial microRNAs can be designed to modulate the expression of multiple targets of a specific pathway. In this review, we describe the metabolic reprogramming associated to cancer, with a special interest in the altered lipid metabolism. Next, we describe specific features of microRNAs that make them relevant to target cancer cell metabolism. Finally, in an attempt to open new therapeutic windows, we emphasize two exciting scenarios for microRNA-mediated intervention that need to be further explored: 1) the cooperation between FA biosynthesis (lipogenesis) and FA oxidation as complementary partners for the survival of cancer cells; and 2) the regulation of the intracellular lipid content modulating both lipid storage into lipid droplets, and lipid mobilization through lipolysis and/or lipophagy.

AMACR amplification and overexpression in primary imatinib-naïve gastrointestinal stromal tumors: a driver of cell proliferation indicating adverse prognosis

Non-random gains of chromosome 5p have been observed in clinically aggressive gastrointestinal stromal tumors, whereas the driving oncogenes on 5p remain to be characterized. We used an integrative genomic and functional approach to identify amplified oncogenes on 5p and to evaluate the relevance of AMACR amplification at 5p13.3 and its overexpression in gastrointestinal stromal tumors. Thirty-seven tumor samples, imatinib-sensitive GIST882 cell line, and imatinib-resistant GIST48 cell line were analyzed for DNA imbalances using array-based genomic profiling. Forty-one fresh tumor samples of various risk categories were enriched for pure tumor cells by laser capture microdissection and quantified for AMACR mRNA expression. AMACR-specific fluorescence in situ hybridization and immunohistochemistry were both informative in tissue microarray sections of 350 independent primary gastrointestinal stromal tumors, including 213 cases with confirmed KIT /PDGFRA genotypes. To assess the oncogenic functions of AMACR, GIST882 and GIST48 cell lines were stably silenced against their endogenous AMACR expression. In 59% of cases featuring 5p gains, two major amplicons encompassed discontinuous chromosomal regions that were differentially overrepresented in high-risk cases, including the one harboring the mRNA-upregulated AMACR gene. Gene amplification was detected in 19.7% of cases (69/350) and strongly related to protein overexpression (p<0.001), although 52% of AMACR-overexpressing cases exhibited no amplification. Both gene amplification and protein overexpression were significantly associated with epithelioid histology, larger size, increased mitoses, higher risk levels, and unfavorable genotypes (all p≤0.03). They were also independently predictive of decreased disease-free survival (overexpression, p<0.001; amplification, p=0.020) in the multivariate analysis. Concomitant with downregulated cyclin D1, cyclin E, and CDK4, AMACR knockdown suppressed cell proliferation and induced G₁-phase arrest, but did not affect apoptosis in both GIST882 and GIST48 cells. In conclusion, AMACR amplification is a mechanism driving increased mRNA and protein expression and conferring aggressiveness through heightened cell proliferation in gastrointestinal stromal tumors.

MicroRNA-101 regulates the viability and invasion of cervical cancer cells

BACKGROUND

Cervical cancer has the second highest morbidity and mortality rates of any malignancy in women worldwide, and it is one of the leading causes of death in Uygur women in Xinjiang China. MicroRNAs are involved in cancer development and progression. Previously, we found that miR-101 is significantly down-regulated in cervical cancer tissues from Uyghur women. The underlying pathophysiology and relevance to tumorigenesis of miR-101 is still largely unknown. The purpose of this study was to elucidate the molecular mechanisms of miR-101 regulation of cervical cancer cell viability and invasion.

MATERIALS AND METHODS

The expression of miR-101 in cervical cancer cell line (SiHa) was detected by real-time PCR. A miR-101 mimic was overexpressed in SiHa cells, and MTT assays were performed to determine the impact on cell proliferation. Cell would heal assays and flow cytometry were used to detect migratory ability and cellular apoptosis, respectively. Immunohistochemistry was performed to assess protein expression of the miR-101 target gene COX-2.

RESULTS

MiR-101 was endogenously expressed in SiHa cells, and alterations in its expression had profound effects on cellular migration and invasion efficiency. Overexpression of miR-101 decreased proliferation in the MTT assay (the mimics at 490 nm absorbance is lower 60% than normal, and decreased cellular motility in the cell would healing assay (transfected: 37 ± 2 m, pre-transfected 184 ± 2 m). Apoptosis rate was significantly higher with overexpression of miR-101 relative to control (transfected: 76.6%, pre-transfected: 3.5%) (P < 0.05). The expression of Cox-2 was decreased in transfected cells.

CONCLUSIONS

MiR-101 likely acts as a tumor suppressor in cervical cancer. Overexpression of miR-101 decreased expression of its target gene Cox-2 and inhibited proliferation and invasion, and promoted apoptosis to suppress tumorigenicity. MiR-101 is a promising new target for the development of therapeutic strategies for the clinical treatment of cervical cancer.

MiR-186 suppresses the growth and metastasis of bladder cancer by targeting NSBP1

BACKGROUND

Increasing evidence has shown that microRNAs function as oncogenes or tumor suppressors in human malignancies, but the roles of miR-186 in human bladder cancer (BC) is still unclear.

METHODS

First, quantitative real-time PCR (qRT-PCR) was performed to detect miR-186 expression in bladder cancer tissues and cell lines. Then, Bioinformatics analysis, combined with luciferase reporter assay demonstrated the target gene of miR-186. Finally, the roles of miR-186 in regulation of tumor proliferation and invasion were further investigated.

RESULTS

Here, our study showed miR-186 was down-regulated in bladder cancer tissues and cell lines. Luciferase reporter assay showed that miR-186 targets NSBP1 3'-untranslated region (UTR) directly and suppresses NSBP1 (HMGN5) expression in human bladder cancer cells. NSBP1 siRNA- and miR-186-mediated NSBP1 knock-down experiments revealed that miR-186 suppresses cell proliferation and invasion through suppression of NSBP1 expression. Expression analysis of a set of epithelial-mesenchymal transition (EMT) markers showed that NSBP1 involves miR-186 suppressed EMT which reducing the expression of mesenchymal markers (vimentin and N-cadherin) and inducing the expression of epithelial marker (E-cadherin).

CONCLUSIONS

Our data first time identified miR-186 as the upstream regulator of NSBP1 and also suggest miR-186-suppressed NSBP1 as a novel therapeutic approach for bladder cancer.

miR-186 regulation of Twist1 and ovarian cancer sensitivity to cisplatin

Epithelial-mesenchymal transition (EMT) has an established role in promoting tumor progression and the acquisition of therapeutic resistance. Here, the EMT phenotype was detected in cisplatin-resistant ovarian cancer tissues and cell lines, and correlated with decreased miR-186 expression, increased Twist1 expression, chemoresistance and poor prognosis in epithelial ovarian cancer (EOC) patients. Introducing miR-186 into EOC cells led to a reduction in twist family bHLH transcription factor 1 (Twist1) expression along with morphological, functional and molecular changes consistent with mesenchymal-to-epithelial transition, G1 cell-cycle arrest and enhanced cell apoptosis, which consequently rendered the cells more sensitive to cisplatin in vitro and in vivo. Furthermore, luciferase reporter and rescue assay results showed that the EMT and drug resistance reversal in response to miR-186 was mediated by Twist1. Collectively, these findings implicate miR-186 as an attractive candidate for overcoming chemoresistance in ovarian cancer therapy.

miR-186 and 326 predict the prognosis of pancreatic ductal adenocarcinoma and affect the proliferation and migration of cancer cells

MicroRNAs can function as key tumor suppressors or oncogenes and act as biomarkers for cancer diagnosis or prognosis. Although high-throughput assays have revealed many miRNA biomarkers for pancreatic ductal adenocarcinoma (PDAC), only a few have been validated in independent populations or investigated for functional significance in PDAC pathogenesis. In this study, we correlated the expression of 36 potentially prognostic miRNAs within PDAC tissue with clinico-pathological features and survival in 151 Chinese patients. We then analyzed the functional roles and target genes of two miRNAs in PDAC development. We found that high expression of miR-186 and miR-326 predict poor and improved survival, respectively. miR-186 was over-expressed in PDAC patients compared with controls, especially in patients with large tumors (>2 cm), lymph node metastasis, or short-term survival (< 24 months). In contrast, miR-326 was down-regulated in patients compared with controls and displayed relatively increased expression in the patients with long-term survival or without venous invasion. Functional experiments revealed that PDAC cell proliferation and migration was decreased following inhibition and enhanced following over-expression of miR-186. In contrast, it was enhanced following inhibition and decreased after over-expression of miR-326. A luciferase assay indicated that miR-186 can bind directly to the 3′-UTR of NR5A2 to repress gene expression. These findings suggest that miR-186 over-expression contributes to the invasive potential of PDAC, likely via suppression of NR5A2, thereby leading to a poor prognosis; high miR-326 expression prolongs survival likely via the decreasing invasive potential of PDAC cells. These two miRNAs can be used as markers for clinical diagnosis and prognosis, and they represent therapeutic targets for PDAC.

MicroRNA-940 suppresses prostate cancer migration and invasion by regulating MIEN1

Background

MicroRNAs (miRNAs) are crucial molecules that regulate gene expression and hence pathways that are key to prostate cancer progression. These non-coding RNAs are highly deregulated in prostate cancer thus facilitating progression of the disease. Among the many genes that have gained importance in this disease, Migration and invasion enhancer 1 (MIEN1), a novel gene located next to HER2/neu in the 17q12 amplicon of the human chromosome, has been shown to enhance prostate cancer cell migration and invasion, two key processes in cancer progression. MIEN1 is differentially expressed between normal and cancer cells and tissues. Understanding the regulation of MIEN1 by microRNA may enable development of better targeting strategies.

Methods

The miRNAs that could target MIEN1 were predicted by in silico algorithms and microarray analysis. The validation for miRNA expression was performed by qPCR and northern blotting in cells and by in situ hybridization in tissues. MIEN1 and levels of other molecules upon miRNA regulation was determined by Western blotting, qPCR, and immunofluorescence. The functional effects of miRNA on cells were determined by wound healing cell migration, Boyden chamber cell invasion, clonal and colony formation assays. For knockdown or overexpression of the miRNA or overexpression of MIEN1 3′UTR, cells were transfected with the oligomiRs and plasmids, respectively.

Results

A novel miRNA, hsa-miR-940 (miR-940), identified and validated to be highly expressed in immortalized normal cells compared to cancer cells, is a regulator of MIEN1. Analysis of human prostate tumors and their matched normal tissues confirmed that miR-940 is highly expressed in the normal tissues compared to its low to negligible expression in the tumors. While MIEN1 is a direct target of miR-940, miR-940 alters MIEN1 RNA, in a quantity as well as cell dependent context, along with altering its downstream effectors. The miR-940 inhibited migratory and invasive potential of cells, attenuated their anchorage-independent growth ability, and increased E-cadherin expression, implicating its role in mesenchymal-to-epithelial transition (MET).

Conclusions

These results, for the first time, implicate miR-940, a regulator of MIEN1, as a promising novel diagnostic and prognostic tool for prostate cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/1476-4598-13-250) contains supplementary material, which is available to authorized users.

Expression of microRNAs and their target genes and pathways associated with ovarian follicle development in cattle

Development of ovarian follicles is controlled at the molecular level by several gene products whose precise expression leads to regression or ovulation of follicles. MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression through sequence-specific base pairing with target messenger RNAs (mRNAs) causing translation repression or mRNA degradation. The aim of this study was to identify miRNAs expressed in theca and/or granulosa layers and their putative target genes/pathways that are involved in bovine ovarian follicle development. By using miRCURY microarray (Exiqon) we identified 14 and 49 differentially expressed miRNAs (P < 0.01) between dominant and subordinate follicles in theca and granulosa cells, respectively. The expression levels of four selected miRNAs were confirmed by qRT-PCR. To identify target prediction and pathways of differentially expressed miRNAs we used Union of Genes option in DIANA miRPath v.2.0 software. The predicted targets for these miRNAs were enriched for pathways involving oocyte meiosis, Wnt, TGF-beta, ErbB, insulin, P13K-Akt, and MAPK signaling pathways. This study identified differentially expressed miRNAs in the theca and granulosa cells of dominant and subordinate follicles and implicates them in having important roles in regulating known molecular pathways that determine the fate of ovarian follicle development.

EZH2 promotes tumor progression by increasing VEGF expression in clear cell renal cell carcinoma

OBJECTIVES

The present study is to evaluate the expression level of enhancer of zeste homolog 2 (EZH2) and vascular endothelial growth factor (VEGF), and analyze their correlations with clinicopathological characteristics and survival in patients with clear cell renal cell carcinoma (CCRCC). The effect of EZH2 on apoptosis and cell proliferation in 786-O renal cancer cell line is investigated.

METHODS

The expression level of EZH2 and VEGF was detected in 185 primary CCRCC patients' tissues using tissue microarray and immunohistochemistry. Small interfering RNA or enhanced green fluorescent protein transfection was employed to investigate the effect of EZH2 inhibition or overexpression on VEGF expression, apoptosis and cell proliferation in 786-O cells using flow cytometry, immunofluorescence microscopy, quantitative real-time reverse-transcription polymerase chain reaction and Western blot analysis.

RESULTS

High expression level of EZH2 and VEGF was observed in advanced CCRCC and correlated with the TNM stage (p = 0.013, p = 0.001) and distant metastasis (p = 0.011, p = 0.038), respectively. EZH2 was positively correlated with VEGF in CCRCC tissues (correlation coefficient = 0.850, p < 0.001). Kaplan-Meier survival analysis revealed that patients with positive EZH2 expression had a shorter overall survival time compared to patients with negative EZH2 expression (34.3 vs. 67.2, p < 0.001). In 786-O cells, EZH2 silencing inhibited VEGF expression and cell proliferation while increasing apoptosis (p < 0.001). EZH2 overexpression promoted VEGF expression and cell proliferation while inhibiting apoptosis (p < 0.001).

CONCLUSIONS

EZH2 correlates positively with VEGF and associates with adverse clinicopathologic characteristics and shorter survival time in CCRCC patients. EZH2 accelerates antiapoptosis and cell cycle in 786-O cells.

MiR-26a inhibits prostate cancer progression by repression of Wnt5a

MicroRNAs (miRNAs) are small noncoding RNAs that are involved in different biological processes by suppressing target gene expression. miRNA microarray analysis revealed a significant decrease of miR-26a in prostate cancer tissues versus their normal counterparts, but the role of miR-26a is needed to investigate. In the present study, we found that miR-26a expression was lower in prostate cancer tissues compared with their normal controls, so did the prostate cancer cells. Next, by lentivirus-mediated gain-of-function studies, it was showed that stable miR-26a inhibited cell proliferation, metastasis, and epithelial mesenchymal transition and induced G1 phase arrest in prostate cancer. It was predicted that Wnt5a was a potential target gene of miR-26a by bioinformatics analysis. Then, luciferase assay and Western blot analysis identified that Wnt5a was a new direct target gene of miR-26a and miR-26a inhibited prostate cancer progression via Wnt5a. Altogether, the findings suggested that miR-26a may function as a tumor suppressor in prostate cancer by targeting Wnt5a.