miRNAs In Hepatocellular Carcinoma Research Articles

MicroRNA-148b-colony-stimulating factor-1 signaling-induced tumor-associated macrophage infiltration promotes hepatocellular carcinoma metastasis

BackgroundMicroRNAs (miRNAs) are small non-coding molecules that exhibit important regulatory roles in various biological or cellular functions, including tumor metastasis. However, the detailed mechanisms of the expression and functions of miRNAs in hepatocellular carcinoma (HCC) have not yet been completely investigated. MethodsIn this study, the levels of miR-148b in HCC cells and patient specimens were determined using qPCR assays. MiR-148b-overexpressing HCC cells were used to investigate the effect of miR-148b in vitro and in vivo. The relationship between the expression of miR-148b and colony stimulating factor-1 (CSF1) in HCC patients and the infiltration of macrophages into the tumor microenvironment were assessed by immunohistochemical staining. ResultsMiR-148b expression was decreased in metastatic HCC cells. A positive association between downregulated miR-148b expression and several clinical parameters, including recurrence, metastasis, and poor prognosis, was observed in patients with HCC. The results of bio-functional experiments indicated that the biological characteristics of HCC cells were not affected by miR-148b deficiency in vitro. However, miR-148b deficiency significantly enhanced the progression and metastasis of HCC in nude mice. By analyzing the gene expression profiles, we demonstrated that CSF1 was regulated by miR-148b and that miR-148b deficiency promoted HCC growth and metastasis through CSF1/CSF1 receptor (CSF1R)-mediated tumor-associated macrophage (TAM) infiltration. These results were supported by the negative relationship between miR-148b and CSF1 expression and TAM infiltration in HCC patients. Moreover, HCC patients with low miR-148b levels and high TAM infiltration were associated with poorer prognosis. ConclusionMiR-148b-CSF1 signaling-induced TAM infiltration promotes HCC metastasis. Therefore, miR-148b plays a suppressor role in HCC and might be a potential prognostic factor and therapeutic candidate for HCC.

Regulation of mTOR singnaling pathway by microRNA in hepatocellular carcinoma

MicroRNA (miRNA) is a non-coding small molecule RNA, which is involved in the occu-rrence and development of tumor as an oncogene or tumor suppressor gene. The abnormal expression of many kinds of miRNAs in hepatocellular carcinoma (HCC) can directly or indirectly act on PI3K, Akt, mTOR, IGF-1R, TGF-β and other signal molecules in mTOR signal pathway, they are crucial in the appreciation, invasion and metastasis of HCC cells. Key words: Carcinoma, hepatocellular; MicroRNAs; TOR serine-threonine kinases

Adipose-derived exosomes deliver miR-23a/b to regulate tumor growth in hepatocellular cancer by targeting the VHL/HIF axis.

Adipose tissue has long been considered to be involved in tumor progression. However, the adipocyte-secreted molecular determinants that regulate hepatocellular cancer progression have not been defined yet. In this study, the expression pattern of exosome miRNAs in hepatocellular carcinoma (HCC) patients with high body fat ratio (BFR) were identified by using low-density microarray. And the targets of exosome-miRNAs in HCC cells were predicted by bioinformatics methods and verified by in vitro as well as in vivo experiments. Here, we show that microRNA-23a/b (miR-23a/b) was significantly upregulated in both serum exosomes and tumor tissues of HCC patients with a high body fat ratio than low BFR. Subsequently, in vitro studies suggested that miR-23a/b was most likely to be derived from adipocytes and was transported into cancer cells via exosomes, thus promoting HCC cell growth and migration. Meanwhile, exosome miR-23a and miR-23b confer chemoresistance by targeting the von Hippel-Lindau/hypoxia-inducible factor axis. Our study provides evidence in that high BFR-related exosome miR23-a/b is a promising target for future treatment of HCC.

MicroRNA‑584 prohibits hepatocellular carcinoma cell proliferation and invasion by directly targeting BDNF.

In recent decades, an increasing number of studies have demonstrated that numerous microRNAs (miRNAs) are dysregulated in hepatocellular carcinoma (HCC); these aberrantly expressed miRNAs are contributing regulators of HCC formation and progression. Thus, revealing the biological roles of miRNAs in HCC may provide novel information on the identification of effective therapeutic targets and valuable diagnosis methods. Herein, reverse transcription‑quantitative PCR was performed to determine the expression profile of miRNA‑584 (miR‑584) in HCC tissues and cell lines. Cell Counting Kit‑8 and cell invasion assays were utilized to evaluate the influence of mIR‑584 overexpression on HCC cell proliferation and invasion, respectively. The present study demonstrated that miR‑584 expression was reduced in HCC tissues and cell lines compared with normal controls. Clinical analysis indicated that decreased miR‑584 expression was significantly associated with tumor size, TNM stage and lymph node metastasis of patients with HCC. Additionally, resumption of miR‑584 expression inhibited proliferation and invasion of HCC cells. Mechanistically, it was demonstrated that miR‑584 can directly interact with the 3'‑untranslated regions of brain‑derived neurotrophic factor (BDNF) mRNA, and reduce its mRNA and protein levels in HCC cells. Furthermore, BDNF was upregulated in HCC tissues, and its level was inversely correlated with miR‑584 expression. Notably, restored BDNF expression antagonized the inhibitory effects of miR‑584 overexpression on HCC cells. In conclusion, miR‑584 may serve tumor‑suppressive roles in HCC by directly targeting BDNF, thus suggesting that miR‑584 may serve as a potential candidate for treatment of patients with this disease.

Exosomal miR-451a Functions as a Tumor Suppressor in Hepatocellular Carcinoma by Targeting LPIN1.

Emerging evidence suggests that exosomal microRNAs (miRNAs) mediate hepatoma progression through the post-translational regulation of their targets. However, characteristically-expressed miRNAs and their functions in the tumor and tumor-associated angiogenesis remain poorly understood. miRNA sequencing (HiSeq 2500 SE50) was performed to identify miRNA species that are involved in the hepatocellular carcinoma (HCC) pathogenesis. We identified miR-451a downregulation according to its expression and TCGA analysis. miR-451a was found to be mainly involved in cell viability, apoptosis, cell cycle and migration both in HCC and endothelial cell lines. LPIN1 was predicted to be a target of this miRNA based on TargetScan, GSEA analysis, and the Uniprot database. We performed real time PCR and dual luciferase assays to confirm these results. We identified that miR-451a is significantly downregulated in serum-derived exosomes from HCC patients, as compared to expression in those from normal individuals. We further confirmed that overexpression of miR-451a functions in HCC and endothelia cells in vitro and in vivo. Exosomal miR-451a, as a tumor suppressor, was found to induce apoptosis both in HCC cell lines and human umbilical vein endothelial cells (HUVECs). In addition, miR-451a suppressed HUVEC migration, tube formation, and vascular permeability. Importantly, we demonstrated that LPIN1 is a critical target of miR-451a, and promotes apoptosis in both HCC and endothelial cells. Our study provides the novel finding that exosomal miR-451a targets LPIN1 to inhibit hepatocellular tumorigenesis by regulating tumor cell apoptosis and angiogenesis. These results have clinical implications regarding the deregulation of miRNAs in HCC.

MiR-584-5p regulates hepatocellular carcinoma cell migration and invasion through targeting KCNE2.

BackgroundHepatocellular carcinoma (HCC) is one of the most commonly diagnosed cancer type. This study was aimed to investigate the role of microRNA‐584‐5p (miR‐584‐5p) in regulating HCC progression.MethodsThe expression of miR‐584‐5p in HCC cell lines was analyzed by quantitative real‐time polymerase chain reaction. Effects of miR‐584‐5p depletion on HCC cell proliferation, migration, and invasion in vitro were analyzed by cell counting kit‐8 assay, wound‐healing assay, and transwell invasion assay. miR‐584‐5p targeting potassium voltage‐gated channel subfamily E regulatory subunit 2 (KCNE2) was identified using bioinformatics algorithm and dual‐luciferase activity reporter assay. Kaplan–Meier Plotter website was used to investigate the effect of miR‐584‐5p or KCNE2 expression on the overall survival of HCC patients.ResultsIn vitro functional assays showed miR‐584‐5p depletion decreased HCC cell proliferation, cell migration, and cell invasion. Moreover, miR‐584‐5p functions by directly targeting KCNE2, and it in turn, mediates the effects of miR‐584‐5p on HCC cell behaviors.ConclusionsThese results demonstrated that miR‐584‐5p functions as an oncogenic miRNA in HCC.

MicroRNA-101-3p suppresses proliferation and migration in hepatocellular carcinoma by targeting the HGF/c-Met pathway.

MicroRNAs are involved in each stage of tumor development. Activation of the hepatocyte growth factor (HGF)/c-Met axis facilitates the proliferation and migration of cancer cells, and the HGF/c-MET pathway provides potential targets for anticancer treatment. However, the interaction between HGF and miRNAs in hepatocellular carcinoma (HCC) remains unknown. Previous studies have shown that miR-101 is downregulated in various types of cancer and acts as a tumor suppressor, but the role of miR-101 in HCC has not yet been well defined. Here, we show that HGF is upregulated while microRNA-101-3p is significantly downregulated in the tumor tissues of HCC. By combining bioinformatics analysis and luciferase reporter assays, we demonstrated that HGF is a direct target of miR-101. In vitro experiments indicated that miR-101 inhibits the migration and proliferation of HCC cells by targeting the HGF/c-MET axis, and in vivo studies showed that overexpressed miR-101 dramatically suppresses tumor growth. Therefore, the present study identifies miR-101 as a negative regulator of HGF/c-MET and suggests that miRNAs can be used as targeted drugs for the clinical treatment of HCC.

MicroRNA-424-5p acts as a potential biomarker and inhibits proliferation and invasion in hepatocellular carcinoma by targeting TRIM29

BackgroundmiRNA-424-5p (miR-424-5p) has been implicated in the development and progression of various tumors. However, the functional mechanisms of miR-424-5p in hepatocellular carcinoma (HCC) are unclear. In this study, we investigated the specific biological functions of miRNA in HCC. MethodsThe expression of miR-424-5p was measured by qRT-PCR in HCC tissues and cell lines. Western blot and immunohistochemistry were used to detect the protein expression level of TRIM29. The relationship between miR-424-5p and the clinicopathological features of HCC patients was analyzed. Cell function experiments were performed to examine proliferation and invasion in HCC cells. The miRNA database was used to predict downstream target genes of miR-424-5p, which were verified by a luciferase reporter assay. Furthermore, cell and animal experiments confirmed that miR-424-5p exerts its biological function through the target gene TRIM29. ResultsmiR-424-5p expression was decreased in HCC tissues and cell lines, and correlated with AFP, TNM stage, intrahepatic metastasis and poor overall survival in HCC. The upregulation of miR-424-5p inhibited cell proliferation and invasion in vitro and suppressed HCC tumor growth in vivo. TRIM29 was confirmed to be the downstream target gene of miR-424-5p. Finally, rescue experiments suggested that the upregulation of TRIM29 could rescue inhibitory effect of miR-424-5p overexpression on cell proliferation and migration. ConclusionmiR-424-5p is a tumor suppressor miRNA that inhibits cell proliferation and invasion via directly modulating TRIM29, which is related to cell proliferation and invasion in HCC. Thus, miR-424-5p may be a potential therapeutic and new prognostic marker for HCC.

Validation of miRNA prognostic power in hepatocellular carcinoma using expression data of independent datasets

Multiple studies suggested using different miRNAs as biomarkers for prognosis of hepatocellular carcinoma (HCC). We aimed to assemble a miRNA expression database from independent datasets to enable an independent validation of previously published prognostic biomarkers of HCC. A miRNA expression database was established by searching the TCGA (RNA-seq) and GEO (microarray) repositories to identify miRNA datasets with available expression and clinical data. A PubMed search was performed to identify prognostic miRNAs for HCC. We performed a uni- and multivariate Cox regression analysis to validate the prognostic significance of these miRNAs. The Limma R package was applied to compare the expression of miRNAs between tumor and normal tissues. We uncovered 214 publications containing 223 miRNAs identified as potential prognostic biomarkers for HCC. In the survival analysis, the expression levels of 55 and 84 miRNAs were significantly correlated with overall survival in RNA-seq and gene chip datasets, respectively. The most significant miRNAs were hsa-miR-149, hsa-miR-139, and hsa-miR-3677 in the RNA-seq and hsa-miR-146b-3p, hsa-miR-584, and hsa-miR-31 in the microarray dataset. Of the 223 miRNAs studied, the expression was significantly altered in 102 miRNAs in tumors compared to normal liver tissues. In summary, we set up an integrated miRNA expression database and validated prognostic miRNAs in HCC.

MicroRNA-374a Promotes Hepatocellular Carcinoma Cell Proliferation by Targeting Mitogen-Inducible Gene 6 (MIG-6).

Hepatocellular carcinoma (HCC) is a disease with poor prognosis rates and ineffective therapeutic options. Previous studies have reported the involvement of mitogen-inducible gene 6 (MIG-6) as a negative regulator in tumor formation. MicroRNAs (miRNAs) play crucial roles in the development of different types of cancer. However, the underlying mechanisms of miRNAs in HCC are poorly understood. This study was aimed to investigate the role of miR-374a in HCC and its role in the regulation of expression of MIG-6. The results showed that MIG-6 overexpression significantly inhibited cell viability of HepG2 cells after 4 days posttransfection. Moreover, MIG-6 was a direct target of miR-374a, and the expression of MIG-6 was remarkably downregulated by the overexpression of miR-374a in HepG2 cells. Furthermore, we found that overexpression of miR-374a promoted cell viability; however, the protective effect was abolished by MIG-6 overexpression. In addition, overexpression of miR-374a activated the EGFR and AKT/ERK signaling pathways by regulation of MIG-6. Our findings suggest that miR-374a could promote cell viability by targeting MIG-6 and activating the EGFR and AKT/ERK signaling pathways. These data provide a promising therapeutic strategy for HCC treatment.

Expression of C19MC miRNAs in HCC associates with stem-cell features and the cancer-testis genes signature

BackgroundIntratumor heterogeneity of hepatocellular carcinoma (HCC) and, among HCC cell subsets, the cancer stem cell population (hCSC), is responsible for therapeutic resistance and disease relapse. AimsTo characterize hCSC-enriched HCCs at the molecular level. MethodsSide population (SP) was used to identify the hCSCs in multiple tumor sampling from different patients and primary HCCs cultures. FACS was used to immunoprofile cultures. miRNAs were profiled in samples and correlated to SP. The Cancer Genome Atlas (TCGA) HCC dataset was analyzed to search for signatures associated with C19MC miRNAs expression. Results were confirmed by immunohistochemistry. ResultsThe miRNA cluster on chromosome 19 (C19MC) was enriched in SP and in HCCs with a high SP fraction. At the molecular level, an elevated C19MC was correlated with expression of precursor transcripts. In TCGA-HCC series, high C19MC expression identified a subset of patients with poorer prognosis, advanced disease and overexpression of the cancer-testis (CT) antigens. These data were confirmed in an independent cohort of HCCs and at the protein level. ConclusionC19MC miRNAs and CT antigens overexpression represents a novel oncogenic pathway in a subset of hCSC-enriched HCCs with dismal prognosis. CT antigens are promising immunotherapy targets. Therefore, these molecular signatures could identify HCCs who could benefit from immunotherapy.

Extract of Stellerachamaejasme L(ESC) inhibits growth and metastasis of human hepatocellular carcinoma via regulating microRNA expression

BackgroundMicroRNAs(miRNAs)are involved in the initiation and progression of hepatocellular carcinoma. ESC, an extract of Stellerachamaejasme L, had been confirmed as a potential anti-tumor extract of Traditional Chinese Medicine. In light of the important role of miRNAs in hepatocellular carcinoma, we questioned whether the inhibitory effects of ESC on hepatocellular carcinoma (HCC) were associated with miRNAs.MethodsThe proliferation inhibition of ESC on HCC cells was measured with MTT assay. The migration inhibition of ESC on HCC cells was measured with transwell assay. The influences of ESC on growth and metastasis inhibition were evaluated with xenograft tumor model of HCC. Protein expressions were measured with western blot and immunofluorescence methods and miRNA profiles were detected with miRNA array. Differential miRNA and target mRNAs were verified with real-time PCR.ResultsThe results showed that ESC could inhibit proliferation and epithelial mesenchymal transition (EMT) in HCC cells in vitro and tumor growth and metastasis in xenograft models in vivo. miRNA array results showed that 69 differential miRNAs in total of 429 ones were obtained in MHCC97H cells treated by ESC. hsa-miR-107, hsa-miR-638, hsa-miR-106b-5p were selected to be validated with real-time PCR method in HepG2 and MHCC97H cells. Expressions of hsa-miR-107 and hsa-miR-638 increased obviously in HCC cells treated by ESC. Target genes of three miRNAs were also validated with real-time PCR. Interestingly, only target genes of hsa-miR-107 changed greatly. ESC downregulated the MCL1, SALL4 and BCL2 gene expressions significantly but did not influence the expression of CACNA2D1.ConclusionThe findings suggested ESC regressed growth and metastasis of human hepatocellular carcinoma via regulating microRNAs expression and their corresponding target genes.

MiR-182-5p promotes hepatocellular carcinoma progression by repressing FOXO3a

BackgroundHigh frequency of recurrence is the major cause of the poor outcomes for patients with hepatocellular carcinoma (HCC). microRNA (miR)-182-5p emerged as a high-priority miRNA in HCC and was found to be related to HCC metastasis. Whether the expression of miR-182-5p in tumor tissue correlated with early recurrence in HCC patients underwent curative surgery was unknown.MethodsReal-time PCR (RT-PCR) and in situ hybridization (ISH) were conducted to assess the expression of miR-182-5p in HCC cells and tissues. Cell Counting Kit-8 (CCK-8), transwell assays were performed to detected cells proliferation and migration ability. Flow cytometry assays were used to detect cell apoptosis rate, and xenograft model was employed to study miR-182-5p in HCC growth and lung metastasis. The target of miR-182-5p was validated with a dual-luciferase reporter assay and western blotting. Immunohistochemistry, immumoblotting, and immunoprecipitation were performed to test relative protein expression.ResultsWe showed that high expression of miR-182-5p in tumor tissues correlated with poor prognosis as well as early recurrence in HCC patients underwent curative surgery. miR-182-5p enhanced motility and invasive ability of HCC cells both in vitro and in vivo. miR-182-5p directly targets 3′-UTR of FOXO3a and repressed FOXO3a expression, activating AKT/FOXO3a pathway to promote HCC proliferation. Notably, miR-182-5p activated Wnt/β-catenin signaling by inhibiting the degradation of β-catenin and enhancing the interaction between β-catenin and TCF4 which was mediated by repressed FOXO3a.ConclusionsConsistently, miR-182-5p can be a potential predictor of early recurrence for HCC patients underwent curative surgery, and FOXO3a plays a key mediator in miR-182-5p induced HCC progression.

The Role of MicroRNAs in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common cancers, leading to the second cancer-related death in the global. Although the treatment of HCC has greatly improved over the past few decades, the survival rate of patients is still quite low. Thus, it is urgent to explore new therapies, especially seek for more accurate biomarkers for early diagnosis, treatment and prognosis in HCC. MicroRNAs (miRNAs), small noncoding RNAs, are pivotal participants and regulators in the development and progression of HCC. Great progress has been made in the studies of miRNAs in HCC. The key regulatory mechanisms of miRNAs include proliferation, apoptosis, invasion, metastasis, epithelial-mesenchymal transition (EMT), angiogenesis, drug resistance and autophagy in HCC. And exosomal miRNAs also play important roles in proliferation, invasion, metastasis, and drug resistance in HCC by regulating gene expression in the target cells. In addition, some miRNAs, including exosomal miRNAs, can be as potential diagnostic and prediction markers in HCC. This review summarizes the latest researches development of miRNAs in HCC in recent years.

The biological and diagnostic role of miRNA's in hepatocellular carcinoma.

The potential of exploitation of miRNA as diagnostic agents and therapeutic tools will likely only be realized when a complete knowledge of their biology is revealed. Despite more than a decade of research, the use of miRNA as diagnostic and therapeutic tools remains a 'work in progress'. The objective of this review is to explore more recent developments in the role of deregulated miRNAs in hepatocellular carcinoma (HCC). This includes emerging insights involving miRNA biogenesis, their deregulation by cancer and their role in deregulating the principal HCC cancer pathways. Specific attention is directed at the role of deregulated miRNAs in HCC in a developing country context with high hepatitis B/C burden, as well as an examination of the challenges that confront the use of extracellular miRNAs as commercially viable diagnostic tools to detect early stage HCC.

A miRNA Combination as Promising Biomarker for Hepatocellular Carcinoma Diagnosis: A Study Based on Bioinformatics Analysis.

Background: miRNAs dysregulate in hepatocellular carcinoma (HCC), showing promise for diagnostic biomarkers which may be found through exploration of differentially expressed miRNAs when comparing HCC and normal liver tissues.Materials and Methods: In the present research, candidate miRNAs were selected and verified using screening dataset GSE12717 and training dataset GSE10694, respectively. A miRNA combination was constructed using stepwise logistic regression analysis and validated using two datasets GSE74618 and TCGA. Target genes of miRNAs in the combination were obtained using a miRNA target gene prediction database. Functional analysis was conducted using an online tool DAVID. We also analyzed the mRNA-Seq data of project LIHC from TCGA to identify the hub target genes of the miRNAs.Results: A miRNA combination, which is composed of hsa-miR-221 and hsa-miR-29c was defined in this study. The miRNA combination is more effective in discriminating HCC patients from normal individuals than individual miRNAs. Additionally, the combined miRNAs showed a lower misdiagnosis rate than AFP in HCC diagnosis. In terms of the functional analysis, a total of 27 target genes of hsa-miR-221 and 96 target genes of hsa-miR-29c were obtained. Among which, INSIG1 was the common target of the two miRNAs. It was also found that both previously mentioned miRNAs played important roles in the regulation of transcription, cell proliferation, and involvement in cancer-related pathways. Lastly, 2 hub target genes of hsa-miR-221 and 16 hub target genes of hsa-miR-29c were obtained.Conclusion: We established a miRNA combination as a promising tool for HCC diagnosis, and the target genes we predicted provide possible points of penetration for researching these two miRNAs in HCC.

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

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

MiR-520f promotes cell aggressiveness by regulating fibroblast growth factor 16 in hepatocellular carcinoma.

Cancer metastasis is a multistep cellular process, which has be confirmed one of mainly causes of cancer associated-death in hepatocellular carcinoma (HCC). MicroRNAs (miRNAs) participate in tumorigenesis function as either tumor suppressor genes or oncogenes. In order to elaborate the critical miRNAs and their targets in HCC, we compared the differential expression of miRNA between HCC tissues and normal tissues. Microarray analysis revealed there were several significantly up-expression miRNAs in HCC, compared to normal solid tissue. Among them, the expression of miR-520f was the most over-expression in HCC cell lines than that in human normal liver cells LO2, as well as up-regulated in HCC than that in the corresponding normal tissues. Moreover, Kaplan Meier-plotter analyses revealed that higher miR-520f levels were negatively correlated with poor overall survival. By applying bioinformatics methods to identify the targeting genes of miRNA, we demonstrated that fibroblast growth factor 16 (FGF16) was the miR-520f-targeted gene. Meanwhile, FGF16 exhibited similar expression patterns to miR-520f in HCC. Forced miR-520f expression accelerated HCC cells proliferation and aggressiveness in vitro and in vivo, whereas down-regulation of miR-520f caused an opposite outcome. Moreover, over-expression of FGF16 was closely related to the metastatic potential of HCC cells. Herein, we also confirmed that ectopic expression of FGF16 in HCC cells promoted proliferation, colony formation, and increased migration, invasion of HCC cells in vitro. Collectively, our results indicated that over-expression of miR-520f and FGF16 was positively associated with aggressive phenotypes and poor survival of patients with HCC, and miR-520f promoted HCC aggressive phenotypes by regulating the expression of FGF16. MiR-520f may be employed as a prognostic factor and therapeutic target for HCC.

Identifying key regulating miRNAs in hepatocellular carcinomas by an omics' method.

The miRNAs play important regulating roles in the pathogenesis of hepatocellular carcinoma (HCC). To uncover key regulating miRNAs in HCC that were neglected by traditional analyzing methods of transcriptomics data, we proposed a novel molecular-network-based omics’ (MNBO) method. With this method, we predicted HCC-regulating miRNAs, and confirmed the role of a novel miR-590-3P/EED axis by a clinical study and in vitro, in vivo wet-experiments. The miR-590-3P is significantly down-regulated in HCC patients. And low level of miR-590-3P in HCC is associated with poor prognosis of patients. In HCC cell lines, the miR-590-3P suppressed cell proliferation by inhibiting the transformation G1 phase to S phases of the cell cycle. Moreover, the miR-590-3P inhibited migration and invasion of HCC cells. Further investigations indicated that miR-590-3P play its roles by inhibiting polycomb protein EED. The experiments in animal model implied miR-590-3P could be a potential therapeutic agent for HCC in the future. In conclusion, the discovery of miR-590-3P revealed the MNBO would be a useful strategy to uncover key regulating miRNAs in HCC.

Factor VII-Induced MicroRNA-135a Inhibits Autophagy and Is Associated with Poor Prognosis in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common and aggressive malignancies worldwide. Treatment outcomes remain poor mainly due to lack of good diagnostic/prognostic markers and limited therapeutic strategies. We previously characterized aberrant activation of the TF/FVII/PAR2 pathway, which subsequently results in decreased autophagy, as a crucial event in malignant progression of HCC.Here, we identified miR-135a as a highly upregulated miRNA in HCC in response to TF/FVII/PAR2 activation. Analyzing 103 HCC patient specimens, we confirmed that miR-135a was frequently elevated in HCC tissues with higher FVII expression compared to adjacent non-cancerous counterparts. Increased miR-135a levels in HCC were also associated with tumor staging, recurrence, microvascular invasion, and decreased disease-free survival. We subsequently identified Atg14, a key component that regulates the formation of autophagosome as a direct target of miR-135a. Ectopic expression of miR-135a suppressed Atg14 levels and inhibited the autophagic processes. Our results indicate strong positive correlations between miR-135a levels and malignant behaviors in HCC patients and also suggest novel functions of miR-135a in regulation of autophagy, which could be useful as a potential target for prognostic and therapeutic uses.