MiR-146a-5p inhibits cell proliferation and cell cycle progression in NSCLC cell lines by targeting CCND1 and CCND2

Differences in microRNA expression between melanoma and healthy adjacent skin

Background

The tumor microenvironment is composed of cancer-associated fibroblasts, tumor-associated macrophages, endothelial cells, immune cells, signaling molecules and extracellular matrix structures, which closelycommunicate with the tumor via multiple mechanisms. MicroRNAs are paracrine regulators that provide a direct interaction between the microenvironment and cancer cells. In the presentstudy, we aimed to identify the microRNA expression profile in melanoma compared with thatin healthy adjacent skin, with a further assessment of altered microRNA signaling pathways and target genes.

Methods

Formalin-fixed paraffin-embedded (FFPE) melanoma tissue samples were separated by dissection into tumor and surrounding health tissue fragments. MicroRNA expression profiles were obtained by microarray using Gene Atlas Microarray System (Affymetrix, California, USA). To confirm microarray results real-time PCR was carried out. Bioinformatic analysis was performed using the DIANA-miRPath v.3.0 database. Target genes for miR-146a-5p were determined using three algorithms: TargetScan 7.0, miRWalk 2.0 and miRTarBase v.4.5.

Results

A microarray profiling revealed 143 microRNAs asdifferent in tumor versus adjacent tissues. Expression level of hsa-miR-146a-5p showedto be higher in melanoma cells as compared to thehealthy adjacent skin. The bioinformatic study has determined several signaling cascades associated with miR-146a-5p:Toll-like receptor pathway, NF-κB pathway, ErB pathway, and measles signaling pathway. The 38 target genes have been shown for miR-146a-5p of which NRAS gene is known asone of the most frequent mutated in melanoma.

Conclusions

Elucidation of the role of miR-146-a-5p in complex interactions between the tumor and the cells of healthy adjacent skin is necessary for our understanding of the mechanisms oftumor progression. Significant differences found between cancer cells and adjacent tissues in microRNA expression profile corresponding to divergent mRNA/protein levels in these structures should be taken into account when tumor samples characterization estimatedby high-throughput methods.

Electronic supplementary material

The online version of this article (10.1186/s12895-018-0081-1) contains supplementary material, which is available to authorized users.

Systems pharmacology uncover the mechanism of anti-non-small cell lung cancer for Hedyotis diffusa Willd

Non-small cell lung cancer (NSCLC) has become one of the most general malignancies in the world and has been shown to be the leading cause of cancer-related deaths. Traditional Chinese medicine (TCM) is considered to be a useful medicine for survival, and has been used in Asia for thousands of years. Hedyotis diffusa Willd (HDW) is an important folk herb that is used in clinical treatment of various cancers in various Chinese medicine prescriptions. However, its underlying mechanism of action remains unclear. Presently, we used an innovative system-pharmacology platform to systematically uncover the pharmacological mechanisms of HDW in the treatment of NSCLC from molecules, targets, and pathway levels. The results show that HDW treatment of NSCLC may activate immunity, achieve anti-inflammatory, anti-proliferative and anti-migration therapeutic effects by regulating multiple pathways. This research provides a new idea for understanding the mechanism of TCM and promotes to develop potential drugs from HDW in modern medicine.

MicroRNA-146 protects A549 and H1975 cells from LPS-induced apoptosis and inflammation injury

Pneumonia is an inflammatory condition affecting the lungs, in which pro-inflammatory cytokines are secreted. It has been shown that microRNA-146 (miR-146) is involved in the regulation of immune and inflammatory responses. The present study explored the protective effects of miR-146 overexpression on lipopolysaccharide (LPS)-mediated injury in A549 and H1975 cells. In this study, A549 and H1975 cells were transfected with miR-146 mimic or inhibitor, and then were subjected with LPS. Thereafter, cell viability, colony formation capacity, apoptosis, the release of proinflammatory factors, Sirt1 expression, and the expression of NF-κB and Notch pathway proteins were respectively assessed. As a result, miR- 146 overexpression exerted protective functions on LPS-damaged A549 and H1975 cells, as evidenced by the increases in cell viability and colony number, the decrease in apoptotic cell rate, as well as the down-regulations of IL-1, IL-6, and TNF-α. Sirt1 can be positively regulated by miR-146. Furthermore, miR-146 overexpression blocked NF-κB and Notch pathways, while these blocking effects were abolished when Sirt1 was silenced. The findings in the current study indicated that miR-146 protected A549 and H1975 cells from LPS-induced apoptosis and inflammation injury. miR-146 exerted protective functions might be via up-regulation of Sirt1 and thereby blocking NF-κB and Notch pathways.

Role of miR-146a in neural stem cell differentiation and neural lineage determination: relevance for neurodevelopmental disorders

Background

MicroRNAs (miRNAs) are small, non-coding RNAs that regulate gene expression at the post-transcriptional level. miRNAs have emerged as important modulators of brain development and neuronal function and are implicated in several neurological diseases. Previous studies found miR-146a upregulation is the most common miRNA deregulation event in neurodevelopmental disorders such as autism spectrum disorder (ASD), epilepsy, and intellectual disability (ID). Yet, how miR-146a upregulation affects the developing fetal brain remains unclear.

Methods

We analyzed the expression of miR-146a in the temporal lobe of ASD children using Taqman assay. To assess the role of miR-146a in early brain development, we generated and characterized stably induced H9 human neural stem cell (H9 hNSC) overexpressing miR-146a using various cell and molecular biology techniques.

Results

We first showed that miR-146a upregulation occurs early during childhood in the ASD brain. In H9 hNSC, miR-146a overexpression enhances neurite outgrowth and branching and favors differentiation into neuronal like cells. Expression analyses revealed that 10% of the transcriptome was deregulated and organized into two modules critical for cell cycle control and neuronal differentiation. Twenty known or predicted targets of miR-146a were significantly deregulated in the modules, acting as potential drivers. The two modules also display distinct transcription profiles during human brain development, affecting regions relevant for ASD including the neocortex, amygdala, and hippocampus. Cell type analyses indicate markers for pyramidal, and interneurons are highly enriched in the deregulated gene list. Up to 40% of known markers of newly defined neuronal lineages were deregulated, suggesting that miR-146a could participate also in the acquisition of neuronal identities.

Conclusion

Our results demonstrate the dynamic roles of miR-146a in early neuronal development and provide new insight into the molecular events that link miR-146a overexpression to impaired neurodevelopment. This, in turn, may yield new therapeutic targets and strategies.

Electronic supplementary material

The online version of this article (10.1186/s13229-018-0219-3) contains supplementary material, which is available to authorized users.

miR-146a suppresses 5-lipoxygenase activating protein (FLAP) expression and Leukotriene B4 production in lung cancer cells

Arachidonic acid (AA) can be converted into prostaglandins (PGs) or leukotrienes (LTs) by the enzymatic actions of cyclooxygenases (COX-1 and COX-2) or 5-lipoxygenase (5-LO), respectively. PGs and LTs are lipid signaling molecules that have been implicated in various diseases, including multiple cancers. 5-LO and its activating protein (FLAP) work together in the first two conversion steps of LT production. Previous work has suggested a role for LTs in cancer development and progression. MicroRNAs (miRNAs) are small RNA molecules that negatively regulate gene expression post-transcriptionally, and have previously been shown to be involved in cancer. Here, we show that high FLAP expression is associated with lower overall survival in lung adenocarcinoma patients, and FLAP protein is overexpressed in lung cancer cells compared to normal lung cells. Our lab has previously shown that miR-146a regulates COX-2 in lung cancer cells, and this miRNA is also predicted to target FLAP. Transient and stable transfections of miR-146a repress endogenous FLAP expression in lung cancer cells, and reporter assays show this regulation occurs through a direct interaction between the FLAP 3′ untranslated region (UTR) and miR-146a. Restoration of miR-146a also results in decreased cancer cell Leukotriene B4 (LTB₄) production. Additionally, methylation analysis indicates the miR-146a promoter is hypermethylated in lung cancer cell lines. Taken together, this study and previous work from our lab suggest miR-146a is an endogenous dual inhibitor of AA metabolism in lung cancer cells by regulating both PG and LT production through direct targeting of the COX-2 and FLAP 3’ UTRs.

A functional polymorphism in the pre-miR-146a gene is associated with the risk of nonsyndromic orofacial cleft

microRNAs (miRNAs) are widely involved in craniofacial development, and genetic variants of miRNAs may be associated with the risk of nonsyndromic orofacial cleft (NSOC). Here, we systematically selected five single nucleotide polymorphisms (SNPs) of miRNAs and investigated the associations between these variants and NSOC susceptibility in a two-stage case-control study including 1,406 NSOC patients and 1,578 controls from the Chinese population. We found that compared with the C allele, the rs2910164 G allele of pre-miR-146a was associated with an increased risk of NSOC (additive model: odds ratio [OR] = 1.17, 95% confidence interval [CI]: 1.06-1.30, P = 0.002), including both cleft lip with or without cleft palate (CL/P) and cleft palate only (CPO). Bioinformatic prediction and functional assays revealed that the C allele of rs2910164 was significantly associated with inhibited HEK-293 and HEPM cell proliferation and decreased abundance of TRAF6. Both miR-146a and TRAF6 were expressed in the lip tissue samples of NSOC patients, and a moderate inverse correlation was observed between them. Taken together, these results demonstrated that miR-146a/rs2910164 is associated with susceptibility to NSOC, providing novel insights into the genetic etiology and underlying biology of NSOC.

Effect of miR-146a-5p on proliferation and metastasis of triple-negative breast cancer via regulation of SOX5

MicroRNA (miR)-146a-5p functions as a tumor suppressor in various types of cancer. However, the role of miR-146a-5p in the development of triple-negative breast cancer (TNBC) is unclear. The present study aimed to investigate the role of miR-146a-5p in TNBC. The expression level of miR-146a-5p in TNBC tissues and cell lines was initially detected using reverse transcription-quantitative polymerase chain reaction. To predict the target gene of miR-146a-5p, TargetScan software was used and a dual luciferase assay was performed to verify the prediction. Furthermore, in order to explore the role of miR-146a-5p in TNBC, miR-146a-5p was overexpressed in TNBC cells using miR-146a-5p mimics. An MTT assay was performed to detect cell proliferation, and a Transwell assay was conducted to determine cell migration and invasion. Furthermore, western blotting was performed to measure associated protein expression. It was revealed that miR-146a-5p was downregulated in TNBC tissues and cell lines. SOX5 was indicated to be a target gene of miR-146a-5p and was upregulated in TNBC cells. Additionally, miR-146a-5p could inhibit TNBC cell proliferation, migration and invasion, repress the expression of mesenchymal markers (N-cadherin, vimentin and fibronectin) and increase epithelial marker (E-cadherin) expression. Furthermore, SOX5 overexpression eliminated the effects of miR-146a-5p mimics on TNBC cells. In conclusion, the data of the present study indicated that miR-146a-5p inhibits the proliferation and metastasis of TNBC cells by regulating SOX5.

mTOR signaling-related MicroRNAs and Cancer involvement

MicroRNAs (miRNAs) are a class of single-stranded RNAs, 18-23 nucleotides in length that regulate gene expression at the post-transcriptional level. Dysregulation of miRNAs has been closely associated with the development of cancer. In the process of tumorigenesis, mammalian target of rapamycin (mTOR) plays important roles, and the mTOR signaling pathway is aberrant in various types of human cancers, including non-small cell lung cancer (NSCLC), breast cancer, prostate cancer, as well as others. However, the relationship between miRNAs and the mTOR signaling pathway is indistinct. Herein, we not only summarize the progress of miRNAs and the mTOR signaling pathway in cancers, but also highlight their role in the diagnosis and treatment in the clinic.

Predictive analysis of long non-coding RNA expression profiles in diffuse large B-cell lymphoma

Long non-coding RNAs (lncRNAs) are implicated in many tumors. To find novel targets for study of diffuse large B-cell lymphoma (DLBCL), our team performed genome-wide analyses of lncRNA expression in 5 DLBCL cell lines using the 4*180K Agilent lncRNA Chip system, and in normal B cells. Five lncRNAs were validated by quantitative reverse transcription polymerase chain reaction. The differentially expressed lncRNAs and mRNAs were identified via false discovery rate and fold-change filtering. Potential targets correlated with DLBCL were recognized via gene ontology and pathway analysis. Establishment of the co-expression network was done using Cytoscape. In total, 1053 lncRNAs and 4391 mRNAs were dysregulated in DLBCL cells, being comparing with normal B cells. The results suggested that the expressions of the 5 lncRNAs were consistent with the chip results. Several terms including the cell cycle, apoptosis, B cell receptor and NF-κB signaling pathways were important in the progression of DLBCL. The chromosome locations of a few lncRNAs and the associated coexpressed genes were demonstrated by cis-regulatory gene analyses. The results of trans-analyses showed that multiple transcription factors regulated lncRNA and gene expression. Those outstanding lncRNAs in each group were implicated in the regulation of the TF-lncRNA-target gene network. Our study identified a set of lncRNAs differentially expressed in DLBCL cells.

Targeting microRNA/UHRF1 pathways as a novel strategy for cancer therapy

Ubiquitin-like containing plant homeodomain and RING finger domains 1 (UHRF1) is an anti-apoptotic protein involved in the silencing of several tumor suppressor genes (TSGs) through epigenetic modifications including DNA methylation and histone post-translational alterations, and also epigenetic-independent mechanisms. UHRF1 overexpression is observed in a number of solid tumors and hematological malignancies, and is considered a primary mechanism in inhibiting apoptosis. UHRF1 exerts its inhibitory activity on TSGs by binding to functional domains and therefore influences several epigenetic actors including DNA methyltransferase, histone deacetylase 1, histone acetyltransferase Tat-interacting protein 60 and histone methyltransferases G9a and Suv39H1. UHRF1 is considered to control a large macromolecular protein complex termed epigenetic code replication machinery, in order to maintain epigenetic silencing of TSGs during cell division, thus enabling cancer cells to escape apoptosis. MicroRNAs (miRNAs) are able to regulate the expression of its target gene by functioning as either an oncogene or a tumor suppressor. In the present review, the role of tumor suppressive miRNAs in the regulation of UHRF1, and the importance of targeting the microRNA/UHRF1 pathways in order to induce the reactivation of silenced TSGs and subsequent apoptosis are discussed.

Effect of miR‑146a‑5p on tumor growth in NSCLC using chick chorioallantoic membrane assay and bioinformatics investigation

Our previous study demonstrated that the expression of miR-146a-5p was downregulated in non-small cell lung cancer (NSCLC) tissue, which affected the progression and prognosis of patients with NSCLC. Thus, the present study was conducted to investigate the functional mechanism of miR-146a-5p in tumorigenesis and angiogenesis in NSCLC. Following the construction of a H460 NSCLC cell line in which miR-146a-5p was overexpressed via lentivirus transduction, the NSCLC chick embryo chorioallantoic membrane (CAM) model was established by transplanting miR-146a-5p-overexpressing NSCLC cells into the CAM. Then, the size of the neoplasms within the CAM was measured, the vessel ratio was calculated, and the cellular morphology, metastasis and inflammation of tumor cell was observed using hematoxylin and eosin staining. The target genes of miR-146a-5p were predicted by 12 online software programs; these genes were then subjected to Gene Ontology enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway annotations using the Database for Annotation, Visualization and Integrated Discovery 6.7 as well as constructed into a protein interaction network using protein-protein interaction from Search Tool for the Retrieval of Interacting Genes/Proteins. The xenograft tumor size and angiogenesis conditions of the miR-146a-5p-overexpressing group (volume 6.340±0.066 mm³, vessel ratio 9.326±0.083) was obviously restricted (P<0.001) when compared with the low expression group (volume 30.13±0.06 mm³, vessel ratio 16.94±0.11). In addition, marked necrosis along with inflammatory cell infiltration was observed with the HE-stained slices from the miR-146a-5p low expression group. Regarding the results of the target gene prediction, cancer and toll-like receptor signaling were the two most significant pathways represented among the target genes, while JUN, EGFR and RAC1 were the most relevant proteins among the selected potential targets of miR-146a-5p. In a CAM xenograft tumor model, overexpression of miR-146a-5p inhibited the tumorigenesis and angiogenesis of an NSCLC cell line. miR-146a-5p may act as a tumor suppressor gene in NSCLC and have moderate prognostic value in lung cancer.

GSK-J4-Mediated Transcriptomic Alterations in Differentiating Embryoid Bodies

Histone-modifying enzymes are key players in the field of cellular differentiation. Here, we used GSK-J4 to profile important target genes that are responsible for neural differentiation. Embryoid bodies were treated with retinoic acid (10 μM) to induce neural differentiation in the presence or absence of GSK-J4. To profile GSKJ4-target genes, we performed RNA sequencing for both normal and demethylase-inhibited cells. A total of 47 and 58 genes were up- and down-regulated, respectively, after GSK-J4 exposure at a log2-fold-change cut-off value of 1.2 (p-value < 0.05). Functional annotations of all of the differentially expressed genes revealed that a significant number of genes were associated with the suppression of cellular proliferation, cell cycle progression and induction of cell death. We also identified an enrichment of potent motifs in selected genes that were differentially expressed. Additionally, we listed upstream transcriptional regulators of all of the differentially expressed genes. Our data indicate that GSK-J4 affects cellular biology by inhibiting cellular proliferation through cell cycle suppression and induction of cell death. These findings will expand the current understanding of the biology of histone-modifying enzymes, thereby promoting further investigations to elucidate the underlying mechanisms.

miR-146a promotes growth of osteosarcoma cells by targeting ZNRF3/GSK-3β/β-catenin signaling pathway

MicroRNA-146a-5p (miR-146a) functions as a tumor suppressor or oncogene involved in multiple biological processes. But, the underlying molecular mechanisms by which miR-146a contributes to osteosarcoma (OS) remain unclear. The correlation of miR-146a expression with clinicopathologic characteristics and prognosis of OS patients was analyzed by Kaplan-Meier and Cox regression analysis. Cell growth in vitro and in vivo was assessed by MTT, cell colony formation and animal models. The target of miR-146a was identified by bioinformatics software and gene luciferase reporter. As a result, miR-146a expression was substantially elevated in OS tissues and was positively associated with the tumor size (P=0.001) and recurrence (P=0.027) of OS patients. Moreover, knockdown of miR-146a suppressed cell proliferation and colony formation in vitro and in vivo. In addition, zinc and ring finger 3 (ZNRF3) was identified as a direct target of miR-146a in OS cells, and was negatively correlated with miR-146a expression in OS tissues. Overexpression of ZNRF3 inhibited cell growth and rescued the tumor-promoting role of miR-146a via inhibition of GSK-3β/β-catenin signaling pathway. Taken together, miR-146a may function as an oncogene in OS cells by targeting ZNRF3/GSK-3β/β-catenin signaling pathway, and represent a promising biomarker for OS patients.

MicroRNA-34a/EGFR axis plays pivotal roles in lung tumorigenesis

MicroRNAs (miRNAs) are vital in the regulation of tumor progression and invasion. Dysregulation of miRNAs has been linked to the development of various types of human cancers, including non-small-cell lung cancer (NSCLC). However, the effect of miRNA-34a (miR-34a), a key regulator of tumor suppression, on the tumorigenesis of NSCLC has not been fully elaborated. Herein, we reveal that miR-34a is significantly downregulated in NSCLC tissues and cell lines, suggesting that miR-34a might function as a tumor suppressor in lung cancer. We also confirmed that epidermal growth factor receptor (EGFR) is a direct target of miR-34a, and our data reveal that siRNA knockdown of EGFR can inhibit cell proliferation, promote apoptosis and arrest cell-cycle progression. In addition, EGFR can reverse the suppressive function of miR-34a overexpression on proliferation and cell apoptosis. Furthermore, in vivo experiments demonstrated that miR-34a suppress tumor growth, both in the A549 xenograft model, as well as in the metastatic tumors in nude mice. Taken together, our findings suggest that miR-34a inhibits NSCLC tumor growth and metastasis through targeting EGFR.

Plasma microRNA alterations between EGFR-activating mutational NSCLC patients with and without primary resistance to TKI

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have obtained excellent therapeutic effects against non-small cell lung cancer (NSCLC) harboring activating EGFR mutations. However, some patients have exhibited primary resistance which becomes a major obstacle in effective treatment of NSCLC. The mechanisms of EGFR-TKIs resistance involved are still poorly understood. Many studies suggest that miRNAs play an important role in regulating drug sensitivity of EGFR-TKIs. The aim of the present study was to examine differentially expressed miRNAs in plasma between EGFR-TKIs sensitive and EGFR-TKIs primary resistance patients. MiRNA microarray of plasma from patients' blood identified 16 differentially expressed miRNAs of which 15 (hsv2-miR-H19, hsa-miR-744-5p, hsa-miR-3196, hsa-miR-3153, hsa-miR-4791, hsa-miR-4803, hsa-miR-4796-3p, hsa-miR-372-5p, hsa-miR-138-2-3p, hsa-miR-16-1-3p, hsa-miR-1469, hsa-miR-585-3p, ebv-miR-BART14-5p, hsa-miR-769-3p, hsa-miR-548aq-5p) were down regulated while only hsa-miR-503-3p was up regulated in primary resistant patients' plasma. Volcano plot and hierarchical clustering were performed to examine the accuracy of the miRNAs. Then validation with quantitative real-time PCR was performed and the result was in accordance with the array data. Functional analysis of these differentially expressed miRNAs with Ingenuity Pathway Analysis (IPA) revealed a common signaling network including MYC, CCND1, IGF1 and RELA. In conclusion, our finding may play important role in understanding the mechanisms underlying the problem and should be further evaluated as potential biomarkers in primary resistance of NSCLC.

MicroRNA-107-5p suppresses non-small cell lung cancer by directly targeting oncogene epidermal growth factor receptor

MicroRNAs (miRNAs) are dysregulated in cancers, including human non-small cell lung cancer (NSCLC). The function of MicroRNA-107-5p (miR-107-5p) in NSCLC is not fully elucidated. Epidermal growth factor receptor (EGFR) is a cancer-driven gene in tumorigenesis. In this study, we found that miR-107-5p was significantly decreased in NSCLC tissues and NSCLC cell lines. Moreover, our results indicated that miR-107-5p could suppress cell proliferation, inhibit metastasis, impede cell cycle, and promote apoptosis via directly targeting EGFR. We also investigated roles of miR-107-5p in vivo. The results showed that it could inhibit tumor growth. Therefore, our study demonstrated that miR-107-5p not only suppressed the progression in NSCLC cells by inhibiting the expression of EGFR, but also could be a promising and a new potential therapeutic target for lung cancer.

Aryl hydrocarbon receptor (AhR)-dependent regulation of pulmonary miRNA by chronic cigarette smoke exposure

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor historically known for its toxic responses to man-made pollutants such as dioxin. More recently, the AhR has emerged as a suppressor of inflammation, oxidative stress and apoptosis from cigarette smoke by mechanisms that may involve the regulation of microRNA. However, little is known about the AhR regulation of miRNA expression in the lung in response to inhaled toxicants. Therefore, we exposed Ahr^−/− and Ahr^+/− mice to cigarette smoke for 4 weeks and evaluated lung miRNA expression by PCR array. There was a dramatic regulation of lung miRNA by the AhR in the absence of exogenous ligand. In response to cigarette smoke, there were more up-regulated miRNA in Ahr^−/− mice compared to Ahr^+/− mice, including the cancer-associated miRNA miR-96. There was no significant change in the expression of the AhR regulated proteins HuR and cyclooxygenase-2 (COX-2). There were significant increases in the anti-oxidant gene sulfiredoxin 1 (Srxn1) and FOXO3a- predicted targets of miR-96. Collectively, these data support a prominent role for the AhR in regulating lung miRNA expression. Further studies to elucidate a role for these miRNA may further uncover novel biological function for the AhR in respiratory health and disease.

MicroRNA-206 acts as a tumor suppressor in bladder cancer via targeting YRDC

Accumulating evidence suggested that microRNA (miRNA) plays important regulatory roles in the initiation and development of various cancers. Previous study showed that microRNA-206 (miR-206) is dysregulated in human bladder cancer tissues, however, the biological function and underlying mechanisms of miR-206 in human bladder cancer remain unknown. In the present study, we aimed to investigate the clinical significance of miR-206 and its target gene YRDC in human bladder cancer, and to determine its effects on oncogenic phenotypes of this disease. Our results showed that miR-206 expression was downregulated significantly in bladder cancer tissues and cell lines compared with adjacent normal bladder tissues and human bladder epithelial immortalized SV-HUC-1 cell line, respectively. Overexpression of miR-206 reduced the expression of YRDC and inhibited bladder cancer cell proliferation, colony formation, migration, invasion and induced cell cycle arrest at G0/G1 phase. In addition, knockdown of YRDC exhibited similar effects with miR-206 overexpression in bladder cancer cells and restoration of YRDC partially reversed the effects of miR-206 in bladder cancer cells. These findings indicated that mir-206 might be a novel target for bladder cancer therapy by targeting YRDC.