MicroRNA-379 Suppresses Cervical Cancer Cell Proliferation and Invasion by Directly Targeting V-crk Avian Sarcoma Virus CT10 Oncogene Homolog-Like (CRKL)

Regulation and tumor-suppressive function of the miR-379/miR-656 (C14MC) cluster in cervical cancer

Cervical cancer (CC) is a key contributor to cancer-related mortality in several countries. The identification of molecular markers and the underlying mechanism may help improve CC management. We studied the regulation and biological function of the chromosome 14 microRNA cluster (C14MC; miR-379/miR-656) in CC. Most C14MC members exhibited considerably lower expression in CC tissues and cell lines in The Cancer Genome Atlas (TCGA) cervical squamous cell carcinoma and endocervical adenocarcinoma patient cohorts. Bisulfite Sanger sequencing revealed hypermethylation of the C14MC promoter in CC tissues and cell lines. 5-aza-2 deoxy cytidine treatment reactivated expression of the C14MC members. We demonstrated that C14MC is a methylation-regulated miRNA cluster via artificial methylation and luciferase reporter assays. C14MC downregulation correlated with poor overall survival and may promote metastasis. C14MC activation via the lentiviral-based CRISPRa approach inhibited growth, proliferation, migration, and invasion; enhanced G2/M arrest; and induced senescence. Post-transcriptional regulatory network analysis of C14MC transcriptomic data revealed enrichment of key cancer-related pathways, such as metabolism, the cell cycle, and phosphatidylinositol 3-kinase (PI3K)-AKT signaling. Reduced cell proliferation, growth, migration, invasion, and senescence correlated with the downregulation of active AKT, MYC, and cyclin E1 (CCNE1) and the overexpression of p16, p21, and p27. We showed that C14MC miRNA activation increases reactive oxygen species (ROS) levels, intracellular Ca2+ levels, and lipid peroxidation rates, and inhibits epithelial-mesenchymal transition (EMT). C14MC targets pyruvate dehydrogenase kinase-3 (PDK3) according to the luciferase reporter assay. PDK3 is overexpressed in CC and is inversely correlated with C14MC. Both miR-494-mimic transfection and C14MC activation inhibited PDK3 expression. Reduced glucose uptake and lactate production, and upregulation of PDK3 upon C14MC activation suggest the potential role of these proteins in metabolic reprogramming. Finally, we showed that C14MC activation may inhibit EMT signaling. Thus, C14MC is a tumor-suppressive and methylation-regulated miRNA cluster in CC. Reactivation of C14MC can be useful in the management of CC.

Expression of microRNA-379 reduces metastatic spread of prostate cancer

Introduction

Prostate cancer (PCa) is the most common type of cancer in males, and the metastatic form is a leading cause of death worldwide. There are currently no curative treatments for this subset of patients. To decrease the mortality of this disease, greater focus must be placed on developing therapeutics to reduce metastatic spread. We focus on dissemination to the bone since this is both the most common site of metastatic spread and associated with extreme pain and discomfort for patients. Our strategy is to exploit microRNAs (miRNAs) to disrupt the spread of primary PCa to the bone.

Methods

PCa cell lines were transduced to overexpress microRNA-379 (miR-379). These transduced PCa cells were assessed using cell growth, migration, colony formation and adhesion assays. We also performed in vivo intracardiac injections to look at metastatic spread in NSG mice. A cytokine array was also performed to identify targets of miR-379 that may drive metastatic spread.

Results

PCa cells with increased levels of miR-379 showed a significant decrease in proliferation, migration, colony formation, and adhesion to bone cells in vitro. In vivo miR-379 overexpression in PC3 cells significantly decreased metastatic spread to bone and reduced levels of miR-379 were seen in patients with metastases. We identified GDF-15 to be secreted from osteoblasts when grown in conditioned media from PCa cells with reduced miR-379 levels.

Discussion

Taken together, our in vitro and in vivo functional assays support a role for miR-379 as a tumour suppressor. A potential mechanism is unravelled whereby miR-379 deregulation in PCa cells affects the secretion of GDF-15 from osteoblasts which in turn facilitates the metastatic establishment in bone. Our findings support the potential role of miR-379 as a therapeutic solution for prostate cancer.

miRNAs role in cervical cancer pathogenesis and targeted therapy: Signaling pathways interplay

Cervical cancer (CC) is the primary cause of cancer deaths in underdeveloped countries. The persistence of infection with high-risk human papillomavirus (HPV) is a significant contributor to the development of CC. However, few women with morphologic HPV infection develop invasive illnesses, suggesting other mechanisms contribute to cervical carcinogenesis. MicroRNAs (miRNAs, miRs) are small chain nucleic acids that can regulate wide networks of cellular events. They can inhibit or degrade their target protein-encoding genes. They had the power to regulate CC's invasion, pathophysiology, angiogenesis, apoptosis, proliferation, and cell cycle phases. Further research is required, even though novel methods have been developed for employing miRNAs in the diagnosis, and treatment of CC. We'll go through some of the new findings about miRNAs and their function in CC below. The function of miRNAs in the development of CC and its treatment is one of these. Clinical uses of miRNAs in the analysis, prediction, and management of CC are also covered.

MicroRNA and cyclooxygenase-2 in breast cancer

Cancer remains a major public health problem worldwide and the latest statistics show that breast cancer (BC) is among the most frequent in women. MicroRNAs (miRNAs; miRs) and cyclooxygenase-2 (COX-2) are new diagnostic and therapeutic biomarkers for monitoring BC. COX-2 is a prominent tumor-associated inflammatory factor highly expressed in human tumor cells, including BC. Expression of COX-2 contributes to tumor growth, metastasis and recurrence. MiRs are a group of short (~22 nucleotides), noncoding regulatory RNAs that downregulate gene expression post-transcriptionally and play vital roles in regulating cancer development and progression. Interestingly, there are a group of miRNAs differentially expressed in breast tumor tissue. Understanding the pathway linking miRNAs to COX-2 can provide novel insight for suppressing COX-2 expression via gene silencing thereby leading to the development of selective miRNA inhibitors. Further research can also reveal key intermediate players and their potential as therapeutic targets. Given the association between different miRNAs and COX-2 expression in BC, this review presents a comprehensive overview of the current literature concerning how miRNAs and COX-2 signaling interact in BC progression.

MicroRNA 379 Regulates Klotho Deficiency-Induced Cardiomyocyte Apoptosis Via Repression of Smurf1

[Figure: see text].

Crk and CrkL as Therapeutic Targets for Cancer Treatment

Crk and CrkL are cellular counterparts of the viral oncoprotein v-Crk. Crk and CrkL are overexpressed in many types of human cancer, correlating with poor prognosis. Furthermore, gene knockdown and knockout of Crk and CrkL in tumor cell lines suppress tumor cell functions, including cell proliferation, transformation, migration, invasion, epithelial-mesenchymal transition, resistance to chemotherapy drugs, and in vivo tumor growth and metastasis. Conversely, overexpression of tumor cells with Crk or CrkL enhances tumor cell functions. Therefore, Crk and CrkL have been proposed as therapeutic targets for cancer treatment. However, it is unclear whether Crk and CrkL make distinct or overlapping contributions to tumor cell functions in various cancer types because Crk or CrkL have been examined independently in most studies. Two recent studies using colorectal cancer and glioblastoma cells clearly demonstrated that Crk and CrkL need to be ablated individually and combined to understand distinct and overlapping roles of the two proteins in cancer. A comprehensive understanding of individual and overlapping roles of Crk and CrkL in tumor cell functions is necessary to develop effective therapeutic strategies. This review systematically discusses crucial functions of Crk and CrkL in tumor cell functions and provides new perspectives on targeting Crk and CrkL in cancer therapy.

Quantitative assessment of glioblastoma phenotypes in vitro establishes cell migration as a robust readout of Crk and CrkL activity

The expression levels of CT10 regulator of kinase (Crk) and Crk-like (CrkL) are elevated in many human cancers, including glioblastoma (GBM), and are believed to contribute to poor prognosis. Although Crk and CrkL have been proposed as therapeutic targets in these tumors, the lack of a reliable, quantitative assay to measure Crk and CrkL activity has hindered development of inhibitors. Here, we knocked down Crk, CrkL, or both using siRNAs in a human GBM cell line, U-118MG, to determine the respective, quantitative contributions of Crk and CrkL to cellular phenotypes. The combined use of specific and potent Crk and CrkL siRNAs induced effective knockdown of CrkII, CrkI, and CrkL. Whereas Crk knockdown did not affect cell morphology, proliferation, adhesion, or invasion, CrkL knockdown caused shrinkage of cells and inhibition of cell proliferation, adhesion, and invasion. Crk/CrkL double knockdown resulted in more pronounced morphological alterations and more robust inhibition of proliferation, adhesion, and invasion. Furthermore, Crk/CrkL double knockdown completely blocked cell migration, and this effect was rescued by transient overexpression of CrkL but not of Crk. Quantification of protein levels indicated that CrkL is expressed more abundantly than CrkII and CrkI in U-118MG cells. These results demonstrate both the predominant role of CrkL and the essential overlapping functions of Crk and CrkL in U-118MG cells. Furthermore, our study indicates that migration of U-118MG cells depends entirely on Crk and CrkL. Thus, impedance-based, real-time measurement of tumor cell migration represents a robust assay for monitoring Crk and CrkL activities.

miRNA profiles of canine cutaneous mast cell tumours with early nodal metastasis and evaluation as potential biomarkers

Cutaneous mast cell tumours (MCTs) are common skin neoplasms in dogs. MicroRNAs (miRNAs) are post-transcriptional regulators involved in several cellular processes, and they can function as tumour promoters or suppressors. However, the role of miRNAs in canine MCTs has not yet been elucidated. Thus, the current study aimed to characterize miRNA profiles and to assess their value as biomarkers for MCTs. miRNA expression profiles were assessed in formalin-fixed, paraffin-embedded samples by next-generation sequencing. Ten samples were MCT tissues, and 7 were healthy adjacent tissues. Nine dysregulated miRNAs (DE-miRNAs) were then validated using RT-qPCR in a larger group of MCT samples, allowing the calculation of ROC curves and performance of multiple factor analysis (MFA). Pathway enrichment analysis was performed to investigate miRNA biological functions. The results showed that the expression of 63 miRNAs (18 up- and 45 downregulated) was significantly affected in MCTs. Five DE-miRNAs, namely, miR-21-5p, miR-92a-3p, miR-338, miR-379 and miR-885, were validated by RT-qPCR. The diagnostic accuracy of a panel of 3 DE-miRNAs—miR-21, miR-379 and miR-885—exhibited increased efficiency in discriminating animals with MCTs (AUC = 0.9854) and animals with lymph node metastasis (AUC = 0.8923). Multiple factor analysis revealed clusters based on nodal metastasis. Gene Ontology and KEGG analyses confirmed that the DE-miRNAs were involved in cell proliferation, survival and metastasis pathways. In conclusion, the present study demonstrated that the miRNA expression profile is changed in the MCT microenvironment, suggesting the involvement of the altered miRNAs in the epigenetic regulation of MCTs and identifying miR-21, miR-379 and miR-885 as promising biomarkers.

A case–control study of microRNA polymorphisms in gastric cancer screening by SNP chip combined with time of flight mass spectrometry

Aims: To explore new SNP sites of miRNAs associated with gastric cancer, thereby providing valuable biomarkers to diagnose and screen gastric cancer. Materials & methods: A 1:1 case–control study was carried out. Microarrays were used to screen the SNP loci of miRNAs in the genomes of matched pairs of patients, 96 with gastric cancer and 96 healthy controls. For validation, mass spectrometry was used to classify miRNA SNP loci in 622 pairs of subjects. Results: rs7143252 was linked to a higher occurrence of gastric cancer. Conclusion: These results suggest that rs7143252 could be used as a specific biomarker to diagnose and screen gastric cancer.

MicroRNA-379-5p/YBX1 Axis Regulates Cellular EMT to Suppress Migration and Invasion of Nasopharyngeal Carcinoma Cells

Background

Epithelial–mesenchymal transition (EMT) is a major actor modulating the metastasis of nasopharyngeal carcinoma (NPC). Increasing evidence indicates that microRNAs (miRs) are the important regulators of EMT program. However, the potential roles and underlying mechanisms of miR‑379-5p in regulating EMT of NPC cells remain unclear.

Methods

miR-379-5p expression levels in human NPC tissues and cell lines were detected via quantitative real-time PCR (qRT-PCR). Then, the correlations between miR-379-5p expression in NPC tissues and clinicopathologic features and patients’ prognosis were analyzed. The effect of miR-379-5p on the expression of EMT markers in NPC cells was evaluated by Western blot and qRT-PCR. NPC cells’ migration and invasion were evaluated in vitro by Transwell migration and invasion assays, respectively. The target of miR-379-5p was predicted with three publicly available databases and further validated with dual-luciferase reporter assay, qRT-PCR, and Western blot.

Results

The expression of miR-379-5p was significantly decreased in NPC tissues, and its low expression was significantly associated with multiple unfavorable clinicopathological factors and poor prognosis of NPC patients. Meanwhile, miR-379-5p was downregulated in NPC cell lines, and its exotic expression inhibited EMT to reduce the migration and invasion of NPC cells. Furthermore, Y-box binding protein 1 (YBX1) was identified and validated as a direct target of miR-379-5p, and restoring YBX1 expression could reverse the inhibitive effect of miR-379-5p on NPC cell EMT, migration and invasion.

Conclusion

Taken together, our findings indicate that miR-379-5p inhibits the EMT of NPC cells to reduce their migration and invasion abilities by post-transcriptionally suppressing YBX1 expression, providing a novel potential treatment target for NPC patients.

Serum miR-379 expression is related to the development and progression of hypercholesterolemia in non-alcoholic fatty liver disease

Introduction

Non-alcoholic fatty liver disease (NAFLD) has a wide spectrum, eventually leading to cirrhosis and hepatic carcinogenesis. We previously reported that a series of microRNAs (miRNAs) mapped in the 14q32.2 maternally imprinted gene region (Dlk1-Dio3 mat) are related to NAFLD development and progression in a mouse model. We examined the suitability of miR-379, a circulating Dlk1-Dio3 mat miRNA, as a human NAFLD biomarker.

Methods

Eighty NAFLD patients were recruited for this study. miR-379 was selected from the putative Dlk1-Dio3 mat miRNA cluster because it exhibited the greatest expression difference between NAFLD and non-alcoholic steatohepatitis in our preliminary study. Real-time PCR was used to examine the expression levels of miR-379 and miR-16 as an internal control. One patient was excluded due to low RT-PCR signal.

Results

Compared to normal controls, serum miR-379 expression was significantly up-regulated in NAFLD patients. Receiver operating characteristic curve analysis suggested that miR-379 is a suitable marker for discriminating NAFLD patients from controls, with an area under the curve value of 0.72. Serum miR-379 exhibited positive correlations with alkaline phosphatase, total cholesterol, low-density-lipoprotein cholesterol and non-high-density-lipoprotein cholesterol levels in patients with early stage NAFLD (Brunt fibrosis stage 0 to 1). The correlation between serum miR-379 and cholesterol levels was lost in early stage NAFLD patients treated with statins. Software-based predictions indicated that various energy metabolism–related genes, including insulin-like growth factor-1 (IGF-1) and IGF-1 receptor, are potential targets of miR-379.

Conclusions

Serum miR-379 exhibits high potential as a biomarker for NAFLD. miR-379 appears to increase cholesterol lipotoxicity, leading to the development and progression of NAFLD, via interference with the expression of target genes, including those related to the IGF-1 signaling pathway. Our results could facilitate future research into the pathogenesis, diagnosis, and treatment of NAFLD.

Prognostic and predictive roles of microRNA‑411 and its target STK17A in evaluating radiotherapy efficacy and their effects on cell migration and invasion via the p53 signaling pathway in cervical cancer

Cervical cancer is one of the most common gynecological malignancies worldwide. However, the pathogenesis of cervical cancer remains to be fully elucidated. Increasing evidence shows that microRNAs (miRNAs) may be involved in the pathogenesis of cervical cancer. The present study tested the hypothesis that the overexpression of miRNA (miR)-411 may delay, whereas the overexpression of serine/threonine kinase 17a (STK17A) may contribute to, cervical cancer development and progression through the p53 pathway. Cervical cancer tissues and adjacent normal tissues were obtained from 141 patients with cervical cancer following radiotherapy, with efficacy evaluated. The receiver operating characteristic curve was plotted to show the value of miR-411 and STK17A in predicting the efficacy of radiotherapy. Cox's proportional hazards regression model was utilized for multivariate analysis. A series of inhibitors, mimics or small interfering RNAs against STK17A were introduced to validate the regulatory mechanism of miR-411 in governing STK17A, determined with a luciferase reporter gene assay. The expression of miR-411 and STK17A, and the status of the p53 signaling pathway were evaluated. The colony forming ability, proliferation, migration, invasion and apoptosis of CaSki cells were assessed using a colony formation assay, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Transwell assay and flow cytometry, respectively. miR-411 was upregulated but STK17A was reciprocal in cervical tissues. The overexpression of miR-411 and low expression of STK17A were correlated with high efficacy of radiotherapy. miR-411 and STK17A had predictive value for the efficacy of radiotherapy; miR-411 was the protective factor and STK17A was a risk factor for prognosis of cervical cancer. Increasing miR-411 activated the p53 signaling pathway and promoted cell apoptosis, but inhibited cell proliferation, invasion and migration. STK17A, an miR-411 target, increased following miR-411 over-expression, whereas the p53 signaling pathway was activated following STK17A inhibition. It was observed that the effect of miR-411 inhibition was lost following STK17A silencing. These findings indicate that the miR-411-mediated direct suppression of STK17A induces apoptosis and suppresses the proliferation, migration and invasion of human cervical cancer cells via the p53 signaling pathway. Additionally, miR-411 and STK17A have predictive value for the efficacy of radiotherapy.

Clustering analysis of microRNA and mRNA expression data from TCGA using maximum edge-weighted matching algorithms

Background

microRNA (miRNA) is a short RNA (~ 22 nt) that regulates gene expression at the posttranscriptional level. Aberration of miRNA expressions could affect their targeting mRNAs involved in cancer-related signaling pathways. We conduct clustering analysis of miRNA and mRNA using expression data from the Cancer Genome Atlas (TCGA). We combine the Hungarian algorithm and blossom algorithm in graph theory. Data analysis is done using programming language R and Python.

Methods

We first quantify edge-weights of the miRNA-mRNA pairs by combining their expression correlation coefficient in tumor (T_CC) and correlation coefficient in normal (N_CC). We thereby introduce a bipartite graph partition procedure to identify cluster candidates. Specifically, we propose six weight formulas to quantify the change of miRNA-mRNA expression T_CC relative to N_CC, and apply the traditional hierarchical clustering to subjectively evaluate the different weight formulas of miRNA-mRNA pairs. Among these six different weight formulas, we choose the optimal one, which we define as the integrated mean value weights, to represent the connections between miRNA and mRNAs. Then the Hungarian algorithm and the blossom algorithm are employed on the miRNA-mRNA bipartite graph to passively determine the clusters. The combination of Hungarian and the blossom algorithms is dubbed maximum weighted merger method (MWMM).

Results

MWMM identifies clusters of different sizes that meet the mathematical criterion that internal connections inside a cluster are relatively denser than external connections outside the cluster and biological criterion that the intra-cluster Gene Ontology (GO) term similarities are larger than the inter-cluster GO term similarities. MWMM is developed using breast invasive carcinoma (BRCA) as training data set, but can also applies to other cancer type data sets. MWMM shows advantage in GO term similarity in most cancer types, when compared to other algorithms.

Conclusions

miRNAs and mRNAs that are likely to be affected by common underlying causal factors in cancer can be clustered by MWMM approach and potentially be used as candidate biomarkers for different cancer types and provide clues for targets of precision medicine in cancer treatment.

Electronic supplementary material

The online version of this article (10.1186/s12920-019-0562-z) contains supplementary material, which is available to authorized users.

Integrated analysis of circular RNA-associated ceRNA network in cervical cancer: Observational Study

BACKGROUND

Circular RNAs (circRNAs) have displayed dysregulated expression in several types of cancer. Nevertheless, their function and underlying mechanisms in cervical cancer remains largely unknown. This study aimed to describe the regulatory mechanisms in cervical cancer.

METHODS

We downloaded the circRNAs expression profiles from Gene Expression Omnibus database, and RNAs expression profiles from The Cancer Genome Atlas database. We established a circRNA-miRNA-mRNA and circRNA-miRNA-hubgene network. The interactions between proteins were analyzed using the STRING database and hubgenes were identified using MCODE plugin. Then, we conducted a circRNA-miRNA-hubgenes regulatory module. Functional and pathway enrichment analyses were conducted using R packages "Clusterprofile".

RESULTS

Six circRNAs, 15 miRNAs, and 158 mRNAs were identified to construct the ceRNA network of cervical cancer. PPI (protein-protein interaction) network and module analysis identified 7 hubgenes. Then, a circRNA-miRNA-hubgene subnetwork was constructed based on the 1 DEcircRNAs, 3 DEmiRNAs, and 3 DEmRNAs. The KEGG pathway analysis indicated DEmRNAs are involved in progesterone-mediated oocyte maturation, cell cycle, and oocyte meiosis.

CONCLUSION

These ceRNAs are critical in the pathogenesis of cervical and may serve as future therapeutic biomarkers.

Correlation of circulating pro-angiogenic miRNAs with cardiotoxicity induced by epirubicin/cyclophosphamide followed by docetaxel in patients with breast cancer

OBJECTIVE

This study aimed to evaluate predictive value of 14 pro-angiogenic miRNAs for cardiotoxicity induced by epirubicin/cyclophosphamide follow by docetaxel (EC-D) in breast cancer (BC) patients.

METHODS

Three hundred and sixty-three BC patients receiving EC-D neoadjuvant chemotherapy were consecutively enrolled in this prospective cohort study. Peripheral blood sample was obtained from each patient, and plasma was separated. The expressions of 14 pro-angiogenic miRNAs, cardiac troponin I (cTnI) and N-terminal pro brain natriuretic peptide (NT-proBNP) were evaluated. Left ventricular ejection fraction (LVEF) level at C0, the end of 4 cycles of EC chemotherapy (C4), the end of 4 cycles of docetaxel treatment (C8), 3rd months (M3), 6th months (M6), 9th months (M9) and 12th months (M12) after surgery were assessed.

RESULTS

LVEF decreased at C4, C8, M3, M6, M9 and M12 compared with C0, and the total cardiotoxicity incidence was 5.2%. Additionally, the levels of let-7f, miR-17-5p, miR-20a, miR-126, miR-210 and miR-378 were reduced in cardiotoxicity patients. Multivariate logistic regression revealed that miR-17-5p and miR-20a were independently predictive factors for less cardiotoxicity. Receiver operating characteristics (ROC) curve displayed a satisfactory predictive value for lower cardiotoxicity risk with area under curve (AUC) of 0.842 of the combination of the miR-17-5p and miR-20a expressions. In addition, let-7f,miR-126, miR-210 and miR-378 levels negatively correlated with cTnI expression, and let-7f and miR-130a expressions reversely correlated with NT-proBNP level.CONLUSIONS: miR-17-5p and miR-20a could be served as biomarkers for lower cardiotoxicity induced by EC-D neoadjuvant chemotherapy in BC patients.

microRNAs: New prognostic, diagnostic, and therapeutic biomarkers in cervical cancer

Cervical cancer is as a kind of cancer beginning from the cervix. Given that cervical cancer could be observed in women who infected with papillomavirus, regular oral contraceptives, and multiple pregnancies. Early detection of cervical cancer is one of the most important aspects of the therapy of this malignancy. Despite several efforts, finding and developing new biomarkers for cervical cancer diagnosis are required. Among various prognostic, diagnostic, and therapeutic biomarkers, miRNA have been emerged as powerful biomarkers for detection, treatment, and monitoring of response to therapy in cervical cancer. Here, we summarized various miRNAs as an employable platform for prognostic, diagnostic, and therapeutic biomarkers in the treatment of cervical cancer.

The role of miRNAs in the invasion and metastasis of cervical cancer

Cervical cancer (CC) with early metastasis of the primary tumor results in poor prognosis and poor therapeutic outcomes. MicroRNAs (miRNAs) are small, noncoding RNA molecules that play a substantial role in regulating gene expression post-transcriptionally and influence the development and progression of tumors. Numerous studies have discovered that miRNAs play significant roles in the invasion and metastasis of CC by affecting specific pathways, including Notch, Wnt/β-catenin, and phosphoinositide-3 kinase (PI3K)-Akt pathways. miRNAs also effectively modulate the process of epithelial–mesenchymal transition. Many studies provide new insights into the role of miRNAs and the pathogenesis of metastatic CC. In this review, we will offer an overview and update of our present understanding of the potential roles of miRNAs in metastatic CC.