MicroRNA-99a inhibits hepatocellular carcinoma growth and correlates with prognosis of patients with hepatocellular carcinoma

The Circulating Micro-RNAs (-122, -34a and -99a) as Predictive Biomarkers for Non-Alcoholic Fatty Liver Diseases

BACKGROUND

It remains essential for patient safety to develop non-invasive diagnostic tools to diagnose non-alcoholic fatty liver rather than invasive techniques.

AIM

Our case-control study was to address the value of circulating miRNAs as a potential non-invasive biomarker for the diagnosis of non-alcoholic fatty acid diseases (NAFLD) and monitoring of disease progression.

METHODS

Routine clinical assessment, laboratory tests, anthropometric study, and liver biopsy results reported for 210 patients with NAFLD (124 patients of simple steatosis (SS) and 86 of non-alcoholic steatohepatitis (NASH)). Apparently matched for age and gender, healthy participants (n= 90) were enrolled as a control group. Serum samples were tested for micro-RNAs (-122, -34a and -99a) by quantitative-PCR.

RESULTS

By histopathology, 124 of the NAFLD group were of SS and 86 patients were of NASH. Compared with the control subjects, both mi-RNA-122 and -34a levels were increased in NAFLD (p< 001) and at a cut-off = 1.261, mi-RNA-122 had 92% sensitivity, 85% specificity to differentiate NAFLD from healthy controls, while mi-RNA-99a were significantly decreased in NAFLD patients with an observed decrease in disease severity, and at a cut-off = 0.46, miRNA-99a had 94% sensitivity and 96% specificity to discriminate SS from NASH.

CONCLUSION

The integration of a circulating mi-RNA panel to diagnose NAFLD cases and to discriminate between SS and NASH. Large-scale study is still needed to verify the other mi-RNA profiles and their role in NAFLD pathogenesis and targeting therapy.

regQTLs: Single nucleotide polymorphisms that modulate microRNA regulation of gene expression in tumors

Genome-wide association studies (GWAS) have identified single nucleotide polymorphisms (SNPs) associated with trait diversity and disease susceptibility, yet their functional properties often remain unclear. It has been hypothesized that SNPs in microRNA binding sites may disrupt gene regulation by microRNAs (miRNAs), short non-coding RNAs that bind to mRNA and downregulate the target gene. While several studies have predicted the location of SNPs in miRNA binding sites, to date there has been no comprehensive analysis of their impact on miRNA regulation. Here we investigate the functional properties of genetic variants and their effects on miRNA regulation of gene expression in cancer. Our analysis is motivated by the hypothesis that distinct alleles may cause differential binding (from miRNAs to mRNAs or from transcription factors to DNA) and change the expression of genes. We previously identified pathways—systems of genes conferring specific cell functions—that are dysregulated by miRNAs in cancer, by comparing miRNA–pathway associations between healthy and tumor tissue. We draw on these results as a starting point to assess whether SNPs on dysregulated pathways are responsible for miRNA dysregulation of individual genes in tumors. Using an integrative regression analysis that incorporates miRNA expression, mRNA expression, and SNP genotype data, we identify functional SNPs that we term “regulatory QTLs (regQTLs)”: loci whose alleles impact the regulation of genes by miRNAs. We apply the method to breast, liver, lung, and prostate cancer data from The Cancer Genome Atlas, and provide a tool to explore the findings.

Genomics studies have identified single nucleotide polymorphisms (SNPs) associated with trait diversity and disease susceptibility, yet the mechanism of action of many genetic variants remains unclear. MicroRNAs (miRNAs) are a class of small non-coding RNA molecules that base-pair coding mRNAs to regulate gene transcription. We hypothesize that SNP variants may affect the ability of miRNAs to bind their target genes, thus influencing gene regulation. To identify these “regulatory QTLs” (regQTLs), we integrate miRNA expression, mRNA expression, and SNP data to identify miRNAs that are associated with pathway dysregulation in tumors, and assess whether SNPs on these pathways are responsible for disrupted miRNA-gene regulation. This data-driven approach enables the discovery of SNPs whose alleles impact gene regulation by miRNAs, with functional consequences for tumor biology. We detail the method, apply it to data from The Cancer Genome Atlas, and provide a tool to explore the findings.

microRNAs: Key players in virus-associated hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is known as one of the major health problems worldwide. Pathological analysis indicated that a variety of risk factors including genetical (i.e., alteration of tumor suppressors and oncogenes) and environmental factors (i.e., viruses) are involved in beginning and development of HCC. The understanding of these risk factors could guide scientists and clinicians to design effective therapeutic options in HCC treatment. Various viruses such as hepatitis B virus (HBV) and hepatitis C virus (HCV) via targeting several cellular and molecular pathways involved in HCC pathogenesis. Among various cellular and molecular targets, microRNAs (miRNAs) have appeared as key players in HCC progression. miRNAs are short noncoding RNAs which could play important roles as oncogenes or tumor suppressors in several malignancies such as HCC. Deregulation of many miRNAs (i.e., miR-222, miR-25, miR-92a, miR-1, let-7f, and miR-21) could be associated with different stages of HCC. Besides miRNAs, exosomes are other particles which are involved in HCC pathogenesis via targeting different cargos, such as DNAs, RNAs, miRNAs, and proteins. In this review, we summarize the current knowledge of the role of miRNAs and exosomes as important players in HCC pathogenesis. Moreover, we highlighted HCV- and HBV-related miRNAs which led to HCC progression.

MicroRNA-32 Regulates Development and Progression of Hepatocellular Carcinoma by Targeting ADAMTS9 and Affects Its Prognosis

Background

MicroRNA-32 (miR-32) induces cell proliferation and metastasis in hepatocellular carcinoma (HCC), but the detailed mechanisms of miR-32 in regulating oncogenesis and development of HCC have not been clarified. The aim of this study was to investigate the effects of miR-32 on HCC and its clinical pathological significance, as well as to determine the functional connection between miR-32 and ADAMTS9 in HCC.

Material/Methods

Quantitative RT-PCR was used to assess the expression levels of miR-32 in HCC tissues, adjacent non-cancerous tissues, and liver cancer cell lines. In vitro cell proliferation, migration, and invasion assays were performed to confirm the biological functions of miR-32. Quantitative RT-PCR, Western blot analysis, and luciferase reporter assays were used to evaluate the role of miR-32 in the regulation of ADAMTS9.

Results

miR-32 was highly expressed in HCC tissues compared with corresponding adjacent non-cancerous tissues. Over-expression of miR-32 was also found in 3 human liver cancer cell lines: SMMC-7721, Huh7, and HepG2. Moreover, increasing expression of miR-32 in HCC tissues was related to shorter overall survival. In vitro over-expression of miR-32 promoted cell proliferation, migration, and invasion; however, the under-expression of miR-32 revealed the opposite effects. Dual-luciferase reporter assay indicated that miR-32 can directly bind to the 3′-UTR of ADAMTS9. Western blot analysis showed that over-expression of miR-32 decreased expression of ADAMTS9 protein. Rescue tests further verified the connection between miR-32 and ADAMTS9.

Conclusions

Our data indicate that miR-32 accelerates progression in HCC by targeting ADAMTS9, and the abnormal expression of miR-32 is correlated with prognosis and could become a potential therapeutic target.

MiRNA-99a can regulate proliferation and apoptosis of human granulosa cells via targeting IGF-1R in polycystic ovary syndrome

PURPOSE

We aimed to evaluate the regulation of miR-99a to the biological functions of granulosa cells in polycystic ovary syndrome (PCOS) via targeting IGF-1R.

METHODS

We collected aspirated follicular fluid in both patients with and without PCOS. Granulosa cells (GCs) were isolated through Percoll differential centrifugation to detect both miR-99a and IGF-1R expressions. We further transfected COV434 cells with miR-99a mimics to establish a miRNA-99a (miR-99a) overexpression model. We explored the regulation of miR-99a to the proliferation and apoptosis of human GCs via IGF-1R in COV434. The effect of different insulin concentrations on miR-99a expression was also evaluated.

RESULTS

MiR-99a was significantly downregulated while IGF-1R was upregulated in patients with PCOS. MiR-99a can regulate IGF-1R on a post-transcriptional level. After transfection of miR-99a mimics, the proliferation rate was decreased and apoptosis rate was increased significantly in COV434. Exogenous insulin-like growth factor 1 (IGF-1) treatment could reverse the effect of miR-99a. MiR-99a was negatively and dose-dependently regulated by insulin in vitro.

CONCLUSIONS

MiR-99a expression was downregulated in patients with PCOS, the degree of which may be closely related to insulin resistance and hyperinsulinemia. MiR-99a could attenuate proliferation and promote apoptosis of human GCs through targeting IGF-1R, which could partly explain the abnormal folliculogenesis in PCOS.

MiR-545-3p/MT1M axis regulates cell proliferation, invasion and migration in hepatocellular carcinoma

Studies have shown that metallothionein 1 M (MT1M) is a tumor suppressor gene which is frequently down-regulated in human hepatocellular carcinoma (HCC). The methylation of MT1M promoter region is one of the important transcriptional regulation mechanisms that contribute to the loss of its expression. In our study, we found that there are still half of the 55 HCC tumor tissues in our cohort do not share the promoter methylation of MT1M. So, we speculated there maybe another mechanism participating in the downregulation of MT1M in HCC. Then, we provided evidences that miR-545-3p, which served as a tumor promoter, post-transcriptionally regulate MT1M in HCC through binding to its untranslated region (3'UTR). Taking together, we investigated the role of miR-545-3p in the process of HCC through regulating MT1M.

Expression of microRNA-99a-3p in Prostate Cancer Based on Bioinformatics Data and Meta-Analysis of a Literature Review of 965 Cases

BACKGROUND microRNAs (miRNAs) have a role as biomarkers in human cancer. The aim of this study was to use bioinformatics data, and review of cases identified from the literature, to investigate the role of microRNA-99a-3p (miR-99a-3p) in prostate cancer, including the identification of its target genes and signaling pathways. MATERIAL AND METHODS Meta-analysis from a literature review included 965 cases of prostate cancer. Bioinformatics databases interrogated for miR-99a-3p in prostate cancer included The Cancer Genome Atlas (TCGA), the Gene Expression Omnibus (GEO), and ArrayExpress. Twelve computational predictive algorithms were developed to integrate miR-99a-3p target gene prediction data. Bioinformatics analysis data from Gene Ontology (GO), the Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein-protein interaction (PPI) network analysis were used investigate the possible pathways and target genes for miR-99a-3p in prostate cancer. RESULTS TCGA data showed that miR-99a was down-regulated in prostate cancer when compared with normal prostate tissue. Receiver-operating characteristic (ROC) curve area under the curve (AUC) for miR-99a-3p was 0.660 (95% CI, 0.587-0.732) or a moderate level of discriminations. Pathway analysis showed that miR-99a-3p was associated with the Wnt and vascular endothelial growth factor (VEGF) signaling pathways. The PPP3CA and HYOU1 genes, selected from the PPI network, were highly expressed in prostate cancer tissue compared with normal prostate tissue, and negatively correlated with the expression of miR-99a-3p. CONCLUSIONS In prostate cancer, miR-99a-3p expression was associated with the Wnt and VEGF signaling pathways, which might inhibit the expression of PPP3CA or HYOU1.

Combined seven miRNAs for early hepatocellular carcinoma detection with chronic low-dose exposure to microcystin-LR in mice

Aberrant miRNA expression has been detected in various tumor tissues, which may be considered as a marker for early cancer diagnosis. One miRNA has multiple downstream target genes, which can be regulated by multiple upstream other miRNAs. Hence, this dynamic regulation is likely characterized by volatility, and thus, finding the appropriate time point for tests becomes essential for the use of miRNAs as an early marker of tumor diagnosis. In this study, we established a chronic liver cancer progression model in mice by using low doses of the harmful substance microcystin-LR (MC-LR). On the basis of miRNAs microarray assay, we further tested seven miRNAs that showed characteristic expression changes in pre-hepatocarcinogenesis. Our results showed that the levels of four miRNAs (miR-122-5p, miR-125-5p, miR-199a-5p, and miR-503-5p) decreased dramatically, whereas those of two miRNAs (miR-222-5p and miR-590-5p) increased significantly in the early stages, which were all accompanied by an increase in atypia of hepatocytes. MiR-490-5p was a sensitive molecular, suitable only for evaluation of pathological changes in young mice. Therefore the combination the seven of miRNAs for a set may prove to be an effective method in healthy assessment of environmental toxicants for detection of hepatocarcinogenesis caused by hazardous materials.

Biological role and clinical value of miR-99a-5p in head and neck squamous cell carcinoma (HNSCC): A bioinformatics-based study

MicroRNAs (miRNAs) are confirmed to be tumor promoters or suppressors in multiple squamous cell carcinomas (SCCs). miR‐99a‐5p has been demonstrated to be downregulated in cancerous tissues, but its functional role in head and neck SCC (HNSCC) and its mechanism of action have not been fully elucidated. Here, we studied the expression of miR‐99a‐5p in HNSCC and performed a clinical value assessment and then extracted mature expression data from The Cancer Genome Atlas (TCGA) and microarrays from Gene Expression Omnibus (GEO). Furthermore, biological analysis was constructed via online prediction tools. The results revealed that miR‐99a‐5p expression was markedly lower in HNSCC tissues than in normal tissues, which also showed significance in the prognosis of HNSCC. However, its diagnostic value could not be verified due to the lack of body fluid samples. Additionally, miR‐99a‐5p was expressed at higher levels in patients with low histological grade neoplasms than those with high histological grade neoplasms. The age of the patient might also be a possible clinical parameter affecting miR‐99a‐5p expression. Furthermore, miR‐99a‐5p significantly influenced HNSCC progression by regulating the PI3K‐Akt signaling pathway, in which the key target genes were upregulated in 519 HNSCC tissues compared to 44 normal tissues, as determined by the Gene Expression Profiling Interactive Analysis (GEPIA). In conclusion, our study may provide insights into the expression and mechanism of miR‐99a‐5p in HNSCC. Further studies are required to elucidate the role of miR‐99a‐5p and its potential clinical applications for HNSCC.

The tumor suppressor role of miR-155-5p in gastric cancer

Gastric cancer (GC) is the fifth most common type of malignant tumor worldwide and the most common cause of cancer-associated mortality in China. Recent studies revealed that microRNAs (miRNAs) function in the pathogenesis of GC, and that miR-155-5p expression is downregulated in GC tissues. However, the function of miR-155-5p has not been fully identified. In the present study, it was demonstrated that overexpression of miR-155-5p inhibited GC-cell proliferation and promoted apoptosis, while downregulation of miR-155-5p promoted GC-cell proliferation and decreased the cisplatin sensitivity of GC cells. Mitogen-activated protein kinase kinase kinase 10 was demonstrated to be a potential target gene of miR-155-5p. In conclusion, an antitumor role of miR-155-5p in gastric cancer was suggested.

The tumor suppressor role of microRNA-338-3p in renal cell carcinoma

Human renal cell carcinoma (RCC) is the most common type of kidney malignancy in adults accounting for 2-3% of all adult malignancies. In China, RCC accounts for ~0.5% of all cancer-associated mortalities, ranking 16th among all cancer types. For early-stage RCC, surgery is the recommended treatment. Molecularly targeted therapy is the preferred first-line treatment for clear-cell RCC. However, more potential targets are required. MicroRNA-338-3p (miR-338-3p) functions as a tumor suppressor in various cancers, but has not been studied in RCC. Accordingly, the present study investigated the role of miR-338-3p of RCC. It was demonstrated that miR-338-3p was present at low levels in RCC tissues. Also, overexpression of miR-338-3p inhibited cell proliferation and promoted cell apoptosis, and downregulation of miR-338-3p promoted cell proliferation. The 3' untranslated region of AKT serine/threonine kinase 3 was targeted by miR-338-3p. In conclusion, the data of the present study revealed the inhibitory function of miR-338-3p in RCC and suggested that miR-338-3p is novel therapeutic target for RCC, but further investigation is needed.

Co-targeting of IGF1R/mTOR pathway by miR-497 and miR-99a impairs hepatocellular carcinoma development

Persistent activation of IGF1R/mTOR signaling pathway plays crucial role in the development of hepatocellular carcinoma (HCC). Therefore, our goal was to elucidate microRNAs (miRNAs) targeting IGF1R/mTOR and the therapeutic potential of single or dual miRNA on HCC development. In this study, we found that miR-497 and miR-99a that target the 3′-UTR of both IGF1R and mTOR were down-regulated in HCC human tissues and cell lines. Functional assay revealed that ectopic expression of miR-497 or miR-99a in HCC cells resulted in a significant inhibition on tumor growth and invasiveness in vitro and tumor development in vivo via repressing the expression of IGF1R and mTOR. Such inhibitory effect on tumor growth is reversed by application of IGF1 ((IGF1R ligand) or MHY1485 (mTOR agonist) in vitro. Furthermore, we found that simultaneous over-expression of both miR-497 and miR-99a exhibited much stronger inhibitory effects on tumor growth than their individual effect, which is still correlated with significantly stronger repression of IGF1R and mTOR. Overall, our results suggest that miR-497 and miR-99a both function as tumor-suppressive miRNAs by suppressing IGF1R/mTOR signaling pathway. The synergistic actions of these two miRNAs partly correlated with IGF1R and mTOR levels, which may represent new strategies for the molecular treatment of HCC.

MiR-425-5p promotes invasion and metastasis of hepatocellular carcinoma cells through SCAI-mediated dysregulation of multiple signaling pathways

MicroRNAs (miRNAs) play critical roles in hepatocellular carcinoma (HCC) progression and are key determinants of prognosis. In this study, we found that miR-425-5p was elevated in HCC and correlated with poor prognostic clinicopathological features and low post-operative long-term survival. Multivariate survival analysis indicated that miR-425-5p expression was an independent risk factor for overall and disease-free survival. Interestingly, miR-425-5p promoted invasion and metastasis by HCC cells, but not HCC cell proliferation or apoptosis in vitro. SCAI and PTEN were determined to be downstream targets of miR-425-5p. miR-425-5p-mediated effects were inhibited by ectopic expression of SCAI, and PTEN exhibited a smaller inhibitory effect. SCAI also suppressed PTEN expression. In addition, miR-425-5p promoted epithelial-to-mesenchymal transition (EMT), which was antagonized by SCAI. miR-425-5p also promoted HCC cell invasion and metastasis via SCAI-mediated dysregulation of integrin β1-Fak/Src-RhoA/CDC42, PTEN-AKT, and TIMP2-MMP2/MMP9 signaling. Finally, miR-425-5p promoted metastasis in a xenograft mouse model of HCC. These results indicate that miR-425-5p facilitates EMT and extracellular matrix degradation and promotes HCC metastasis through SCAI-mediated dysregulation of multiple signaling pathways. MiR-425-5p is therefore a potential prognostic biomarker and novel therapeutic target in HCC.

MicroRNA-320a inhibits breast cancer metastasis by targeting metadherin

Dysregulated microRNAs play important pathological roles in carcinogenesis that are yet to be fully elucidated. This study was performed to investigate the biological functions of microRNA-320a (miR-320a) in breast cancer and the underlying mechanisms. Function analyses for cell proliferation, cell cycle, and cell invasion/migration, were conducted after miR-320a silencing and overexpression. The specific target genes of miR-320a were predicted by TargetScan algorithm and then determined by dual luciferase reporter assay and rescue experiment. The relationship between miR-320a and its target genes was explored in human breast cancer tissues. We found that miR-320a overexpression could inhibit breast cancer invasion and migration abilities in vitro, while miR-320a silencing could enhance that. In addition, miR-320a could suppress activity of 3′-untranslated region luciferase of metadherin (MTDH), a potent oncogene. The rescue experiment revealed that MTDH was a functional target of miR-320a. Moreover, we found that MTDH was negatively correlated with miR-320a expression, and it was related to clinical outcomes of breast cancer. Further xenograft experiment also showed that miR-320a could inhibit breast cancer metastasis in vivo. Our findings clearly demonstrate that miR-320a suppresses breast cancer metastasis by directly inhibiting MTDH expression. The present study provides a new insight into anti-oncogenic roles of miR-320a and suggests that miR-320a/MTDH pathway is a putative therapeutic target in breast cancer.

Potential tumor suppressing role of microRNA-545 in epithelial ovarian cancer

Epithelial ovarian cancer (EOC) is the most common type of ovarian cancer, which exhibits invasive traits. MicroRNAs (miRNAs/miRs) have been demonstrated to serve important functions in the pathogenesis of EOC. However, the function of miR-545 in EOC remains unknown. In the present study, the function of miR-545 in EOC was analyzed and it was identified that miR-545 is downregulated in EOC tissues and cell lines. Additionally, a low level of miR-545 expression was associated with a low survival rate of patients with EOC. Furthermore, overexpression of miR-545 inhibited cell growth and promoted apoptosis. Suppression of miR-545 promoted cell growth and inhibited apoptosis. Additionally, the RAC-γ serine/threonine-protein kinase gene was targeted by miR-545. Thus, it may be concluded that miR-545 exhibited antitumor traits in EOC.

miR-22 targets YWHAZ to inhibit metastasis of hepatocellular carcinoma and its down-regulation predicts a poor survival

Many miRNAs are associated with the carcinogenesis of hepatocellular carcinoma (HCC) and some exhibit potential prognostic value. In this study, to further confirm the prognostic value of miRNAs in HCC, we employed miRNA-sequencing data of tumor tissues of 372 HCC patients released by The Cancer Genome Atlas (TCGA) and identified 3 miRNAs including miR-22, miR-9-1 and miR-9-2 could be used as independent predictors for HCC prognostic evaluation. As a tumor-suppressive miRNA, miR-22 was down-regulated in HCC tissues. This down-regulation correlated with tumor vascular invasion, Edmondson–Steiner grade, TNM stage, and AFP level. Moreover, biofunctional investigations revealed that miR-22 significantly attenuated cellular proliferation, migration and invasion of HCC cells. Additionally, through gene expression profiles and bioinformatics analysis, YWHAZ was identified to be a direct target of miR-22 and its overexpression partially counteracted the inhibitory effects of miR-22 on HCC cells. Finally, molecular studies further confirmed that miR-22 promoted the accumulation of FOXO3a in nucleus and subsequently reversed invasive phenotype of HCC cells by repressing YWHAZ-mediated AKT phosphorylation. Taken together, these data demonstrate that miR-22 exhibits tumor-suppressive effects in HCC cells by regulating YWHAZ/AKT/FOXO3a signaling and might be used as an independent prognostic indicator for HCC patients.

miR-99a-5p acts as tumor suppressor via targeting to mTOR and enhances RAD001-induced apoptosis in human urinary bladder urothelial carcinoma cells

Introduction

miR-99a-5p, known to play an important role in mammalian target of rapamycin (mTOR) regulation, is downregulated in human bladder cancer. The study aimed to investigate the anticancer activity of miR-99a-5p and the possible mechanism associated with mTOR in bladder cancer cells.

Materials and methods

Vectors expressing miR-99a-5p were transfected into human urinary bladder urothelial carcinoma (5637 and T24) cells. The level of miR-99a-5p was monitored by microRNA (miRNA) quantitative polymerase chain reaction (QPCR). Luciferase reporter assays were performed to verify the direct binding of miR-99a-5p to mTOR transcripts. The mTOR transcripts and protein levels were measured by QPCR and Western blot, respectively. Cell viability of miR-99a-5p-transfected cells was detected by tetrazolium salt (WST-1). Inhibition of mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2) signaling was detected by the phosphorylation of mTOR and AKT using Western blot. The ability of miR-99a-5p to enhance RAD001-induced apoptosis was determined as the expression of cleaved caspase 3 and levels of DNA fragmentation.

Results

Transfection of miR-99a-5p-expressing vector elevated the expression level of miR-99a-5p up to sixfold compared to vector-only controls. The results from luciferase assay verified that miR-99a-5p directly binds to the predicted sequence in the 3′ untranslated region (3′-UTR) of mTOR. The levels of mTOR RNA and protein were decreased in miR-99a-5p-transfected cells. Dual inhibition of mTORC1 and mTORC2 by miR-99a-5p was confirmed by the decreased phosphorylation of mTOR (at Ser2448 and Ser2481), phospho-rpS6 and phospho-4EBP1. The phosphorylation of AKT was significantly inhibited in miR-99a-5p-transfected cells upon RAD001 treatment. Enforced expression of miR-99a-5p potentiated RAD001-induced apoptosis in these cells.

Conclusion

This is the first study showing that miR-99a-5p markedly inhibits the growth of bladder cancer cells via dual inhibition of mTORC1 and mTORC2. Our data demonstrated that forced expression of miR-99a-5p inhibits the feedback of AKT survival pathway and enhances the induction of apoptosis in RAD001-treated bladder cancer cells.

PSC-derived Galectin-1 inducing epithelial-mesenchymal transition of pancreatic ductal adenocarcinoma cells by activating the NF-κB pathway

Galectin-1 has previously been shown to be strongly expressed in activated pancreatic stellate cells (PSCs) and promote the development and metastasis of pancreatic ductal adenocarcinoma (PDAC). However, the molecular mechanisms by which Galectin-1 promotes the malignant behavior of pancreatic cancer cells remain unclear. In this study, we examined the effects of Galectin-1 knockdown or overexpression in PSCs co-cultured with pancreatic cancer (PANC-1) cells. Immunohistochemical analysis showed expression of epithelial-mesenchymal transition (EMT) markers and MMP9 were positively associated with the expression of Galectin-1 in 66 human PDAC tissues. In addition, our in vitro studies showed PSC-derived Galectin-1 promoted the proliferation, invasion, and survival (anti-apoptotic effects) of PANC-1 cells. We also showed PSC-derived Galectin-1 induced EMT of PANC-1 cells and activated the NF-кB pathway in vitro. Our mixed (PSCs and PANC-1 cells) mouse orthotopic xenograft model indicated that overexpression of Galectin-1 in PSCs significantly promoted the proliferation, growth, invasion, and liver metastasis of the transplanted tumor. Moreover, Galectin-1 overexpression in PSCs was strongly associated with increased expression of EMT markers in both the orthotopic xenograft tumor in the pancreas and in metastatic lesions of naked mice. We conclude that PSC-derived Galectin-1 promotes the malignant behavior of PDAC by inducing EMT via activation of the NF-κB pathway. Our results suggest that targeting Galectin-1 in PSCs could represent a promising therapeutic strategy for PDAC progression and metastasis.

MicroRNA-1271 inhibits cellular proliferation of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common causes of cancer-associated mortality worldwide, particularly in China. MicroRNAs (miRs) serve important roles in the pathogenesis of HCC. The present study investigated the function of miR-1271 in HCC. The miR-1271 levels were analyzed by quantitative reverse transcription polymerase chain reaction. Cells growth was examined by MTT assay. Bioinformatics algorithms from TargetScanHuman were used to predict the target genes of miR-1271. The protein level was assayed by western blotting. miR-1271 demonstrated a lower expression level in HCC tissues. Upregulation of miR-1271 suppressed the growth of HepG-2 and Huh-7 cells and induced apoptosis of cells. Forkhead box Q1 (FOXQ1) was targeted by miR-1271. In conclusion, miR-1271 is a novel tumor suppressor that inhibits HCC proliferation and induces cellular apoptosis by targeting FOXQ1 in HCC. The results of the present study may provide a novel therapeutic target of HCC.

Prognostic value of microRNAs in hepatocellular carcinoma: a meta-analysis

Background

Numerous articles reported that dysregulated expression levels of miRNAs correlated with survival time of HCC patients. However, there has not been a comprehensive meta-analysis to evaluate the accurate prognostic value of miRNAs in HCC.

Design

Meta-analysis.

Materials and Methods

Studies, published in English, estimating expression levels of miRNAs with any survival curves in HCC were identified up until 15 April, 2017 by performing online searches in PubMed, EMBASE, Web of Science and Cochrane Database of Systematic Reviews by two independent authors. The pooled hazard ratios (HR) with 95% confidence intervals (CI) were used to estimate the correlation between miRNA expression and overall survival (OS).

Results

54 relevant articles about 16 miRNAs, with 6464 patients, were ultimately included. HCC patients with high expression of tissue miR-9 (HR = 2.35, 95% CI = 1.46–3.76), miR-21 (HR = 1.76, 95% CI = 1.29–2.41), miR-34c (HR = 1.64, 95% CI = 1.05–2.57), miR-155 (HR = 2.84, 95% CI = 1.46–5.51), miR-221 (HR = 1.76, 95% CI = 1.02–3.04) or low expression of tissue miR-22 (HR = 2.29, 95% CI = 1.63–3.21), miR-29c (HR = 1.35, 95% CI = 1.10–1.65), miR-34a (HR = 1.84, 95% CI = 1.30–2.59), miR-199a (HR = 2.78, 95% CI = 1.89–4.08), miR-200a (HR = 2.64, 95% CI = 1.86–3.77), miR-203 (HR = 2.20, 95% CI = 1.61–3.00) have significantly poor OS (P < 0.05). Likewise, HCC patients with high expression of blood miR-21 (HR = 1.73, 95% CI = 1.07–2.80), miR-192 (HR = 2.42, 95% CI = 1.15–5.10), miR-224 (HR = 1.56, 95% CI = 1.14–2.12) or low expression of blood miR-148a (HR = 2.26, 95% CI = 1.11–4.59) have significantly short OS (P < 0.05).

Conclusions

In conclusion, tissue miR-9, miR-21, miR-22, miR-29c, miR-34a, miR-34c, miR-155, miR-199a, miR-200a, miR-203, miR-221 and blood miR-21, miR-148a, miR-192, miR-224 demonstrate significantly prognostic value. Among them, tissue miR-9, miR-22, miR-155, miR-199a, miR-200a, miR-203 and blood miR-148a, miR-192 are potential prognostic candidates for predicting OS in HCC.

MicroRNA-203 suppresses proliferation in liver cancer associated with PIK3CA, p38 MAPK, c-Jun, and GSK3 signaling

Primary liver cancer (hepatocellular carcinoma, HCC) is a leading cause of cancer-related deaths, and alternative ways to treat this disease are urgently needed. In recent years, novel approaches to cancer treatment have been based on microRNAs, small non-coding RNA molecules that play a crucial role in cancer progression by regulating gene expression. Overexpression of some microRNAs has shown therapeutic potential, but whether or not this was the case for microRNA-203 (miR-203) in liver cancer was unknown. Therefore, the aim of this study was to investigate the effect of miR-203 overexpression in liver cancer and explore the related mechanisms. Liver cancer cells from the HepG2 and Hep3B cell lines were transfected with either miR-203 mimics or negative control RNA, and then the cells were subjected to cell viability, cell proliferation, and Western blotting assays. As a result of microRNA-203 overexpression, HepG2 and Hep3B cell viability and cell proliferation significantly declined. Furthermore, microRNA-203 overexpression led to inhibited expression of phosphatidylinositol-4,5-bisphosphate 3-kinase (PIK3)/protein kinase B (Akt), c-Jun, and p38 mitogen-activated protein kinases (p38 MAPK), and restored glycogen synthase kinase 3 (GSK 3) activity in HepG2 cells. Our results suggest that c-Jun, p38 MAPK, PIK3CA/Akt, and GSK3 signaling involved in the effect of miR-203 on the proliferation of HCC cells.

MicroRNA-204-5p inhibits invasion and metastasis of laryngeal squamous cell carcinoma by suppressing forkhead box C1

Background and aim: Understanding the molecular biological mechanisms underlying laryngeal squamous cell carcinoma (LSCC) invasion and metastasis is crucial for diagnosis, treatment, and prognosis. We aimed to examine the expression of the tumor suppressor microRNA-204-5p (miR-204-5p) and its target gene, forkhead box C1 (FOXC1), in human LSCC and explore their roles in the malignant behaviors of LSCC Hep-2 and TU-177 cells. Methods: The regulatory effects of miR-204-5p on the 3' untranslated region of FOXC1 predicted by bioinformatics were tested by dual-luciferase reporter assay. Quantitative RT-PCR was used to detect mRNA expression in 43 fresh samples of LSCC and corresponding adjacent normal mucosa (ANM). FOXC1 protein expression was examined by immunohistochemistry. miR-204-5p mimics and FOXC1 siRNA were transfected into LSCC cell lines Hep-2 and TU-177 to observe malignant behavior. miR-204-5p mimics were injected into Hep-2 or TU-177 xenograft tumors in nude mice to examine tumor growth.Results: The miR-204-5p mRNA level was lower in all 43 LSCC samples than in the ANM samples, but the FOXC1 level was higher in the LSCC samples than in the ANM samples. The miR-204-5p level was lower for stage III and IV cancer and lymph node N+ status samples than for stage I and II cancer and N0 status samples. FOXC1 mRNA and protein levels were higher for N+ than for N0 LSCC. The miR-204-5p mRNA levels were lower in Hep-2 and TU-177 cells than in ANM tissues, but FOXC1 mRNA levels were higher in Hep-2 and TU-177 cells than in ANM tissues. Dual-luciferase reporter assays demonstrated the targeted regulatory effects of miR-204-5p on the FOXC1 3' UTR. Cell proliferation and colony formation was facilitated with miR-204-5p mimics and FOXC1 siRNA, with weaker cell migration and invasion than the controls. Moreover, miR-204-5p overexpression or FOXC1 knockdown inhibited the EMT process in LSCC cells. In vivo experiments demonstrated that injection of miR-204-5p into Hep-2 and TU-177 xenograft tumors in nude mice significantly inhibited tumor growth. Conclusions: miR-204-5p is involved in the invasion and metastasis of LSCC. It has a targeted regulatory effect on FOXC1 expression; malignant LSCC behaviors, including cell proliferation, invasion, and metastasis, are suppressed, and tumor growth in vivo is inhibited. This suggests that miR-204-5p may be a target for molecular therapy of LSCC in the future.

Upregulation of miR-520b promotes ovarian cancer growth

Ovarian cancer is the most common gynecological malignant cancer in female genitalia. Dysregulation or dysfunction of microRNAs (miRs) contribute to cancer development. The role of miR-520b in ovarian cancer remains unclear. The present study investigated the role of miR-520b in ovarian cancer and determined that the expression levels of miR-520b in ovarian cancer tissues and cell lines were upregulated. By contrast, reverse transcription-quantitative polymerase chain reaction and immunohistochemistry revealed that the mRNA and protein expression levels of ring finger protein 216 (RNF216) were downregulated in ovarian cancer, indicating that there was a negative correlation between miR-520b and RNF216. In miR-520b-knockdown cells, downregulation of miR-520b reduced cell proliferation, while upregulation of miR-520b promoted cell proliferation. In addition, RNF216 was predicted by TargetScanHuman and was observed to be targeted by miR-520b. In conclusion, the present data indicated that high expression of miR-520b in ovarian cancer promoted cell growth via RNF216.

Label-free pharmacological profiling based on dynamic mass redistribution for characterization and authentication of hazardous natural products

Natural products are becoming increasingly popular in multiple fields involving medicines, foods and beverages. However, due to the frequent occurrence of poisoning incidents, their toxicity and safety have caused a serious concern. Here we report a method of biosensor-based two-phase pharmacological profiling (BTPP) for discovery, monitor and control of receptor-targeted natural products. BTPP uses a resonant waveguide grating biosensor for label-free and non-invasive detection of intracellular dynamic mass redistribution (DMR), a phenomenon caused by protein relocalization after receptors receiving stimulation from toxicants. The method can not only facilitate the identification of hazardous materials but also quantify their bioactivity by EC₅₀. As a proof of concept, the method was successfully applied to recognize Daturae Flos (DF), an herb that can antagonize muscarinic acetylcholine M₂ receptor and further cause poisoning, from other easily confused species. BTPP combined with high performance liquid chromatography revealed that scopolamine and hyoscyamine in DF were the key marker compounds. Moreover, the method accurately picked out 2 M₂ receptor antagonists from 25 natural compounds, displaying its potential in high-throughput screening. This study provides a systematic illustration about the establishment, applicability and advantages of BTPP, which contributes to the safety assessment of natural products in related fields.

miRNA-708 functions as a tumour suppressor in hepatocellular carcinoma by targeting SMAD3

Hepatocellular carcinoma (HCC) is the most frequent subtype of primary liver cancer and the third most common cause of cancer-associated mortality worldwide. Previous studies have reported that microRNAs (miRNAs) serve key roles in the carcinogenesis and progression of HCC by regulating gene expression. The present study investigated the expression patterns, biological roles and underlying mechanisms of miRNA-708 (miR-708) in HCC. The expression levels of miR-708 in HCC tissue samples and cell lines were examined. Cell proliferation, migration and invasion assays were used to evaluate the effect of miR-708 on HCC cells. In addition, bioinformatic and western blotting analyses, and dual luciferase reporter assays were performed to investigate the direct gene target of miR-708. The results of the present study demonstrated that miR-708 expression was significantly decreased in HCC tissue samples and cell lines. In addition, the expression level of miR-708 was associated with increased HCC tumour stage. Furthermore, ectopic expression of miR-708 suppressed HCC cell proliferation, migration and invasion. The results of the present study also indicated that miR-708 targets SMAD family member 3 directly in vitro. The results of the present study indicated that miR-708 may be a novel target for future HCC therapy.

消化系肿瘤循环微小RNA研究进展

微小RNA(microRNA, miRNA)是一类内源性的、21-25个碱基长度的小分子非编码RNA, 在转录后水平调节靶基因mRNA表达, 并在多种肿瘤的发生和发展中过程中发挥重要的促癌或抑癌作用. 不同肿瘤类型有着各自特异性miRNA表达谱. 近来研究发现游离的miRNA可稳定地存在于血清和血浆中, 并作为一个潜在的非侵入性生物标志物, 该研究领域已成为当前临床研究的热点. 循环中的miRNA作为肿瘤相关生物标志物, 不仅可以反应早期肿瘤的存在, 而且可以检测肿瘤的发展、复发情况以及对药物敏感性. 这种"液体活检"的方法可提供非侵袭性的和持续表达的生物标志物, 并且为肿瘤患者个体化治疗提供一种新的策略. 本文综述了近几年循环miRNA在实体瘤尤其是消化系肿瘤的研究进展, 并探讨了其作为消化系恶性肿瘤潜在的诊断标志物或治疗靶点的发展前景.

microRNA-99a Reduces Lipopolysaccharide-Induced Oxidative Injury by Activating Notch Pathway in H9c2 Cells

microRNA-99a (miR-99a) is recently recognized as a key regulator in various cancers and cardiovascular diseases. In the present study, we sought to investigate the effects of miR-99a in rat cardiomyocyte H9c2 cells against oxidative injury induced by lipopolysaccharide (LPS).MTT assay, reactive oxygen species (ROS) assay, flow cytometry and lactate dehydrogenase (LDH) assay were respectively used to explore viability, ROS levels, apoptosis, and cell death in H9c2 cells. Quantitative PCR (qRT-PCR) was performed to confirm the expression of miR-99a. Western blot was performed to determine the expression of Notch pathway factors.LPS could significantly suppress viability and increase cell death, apoptosis, and ROS level (P < 0.05). However, miR-99a could significantly increase the viability and decrease apoptosis and ROS level of H9c2 cells (P < 0.05). Overexpression of miR-99a could activate a Notch pathway and regulate the expression of B-cell CLL/lymphoma 2 (BCL2) and cleaved caspase 3.Our study found that overexpression of miR-99a could attenuate LPS-induced oxidative injury in H9c2 cells, possibly via a Notch pathway. These findings suggest that miR-99a may be a key factor in cardiomyocyte oxidative injury and could be a new therapeutic strategy for cardiovascular diseases.

PLGA-based dual targeted nanoparticles enhance miRNA transfection efficiency in hepatic carcinoma

Hepatic carcinoma (HCC) is a lethal disease associated with high morbidity and poor prognosis. Recently years, gene therapies have offered novel modalities to improve the prognosis of HCC patients. MicroRNA-99a (miR-99a) is frequently down-regulated in HCC, where it acts as a tumor suppressor. Therefore, we constructed monomethoxy (polyethylene glycol)-poly(D,L-lactide-co-glycolide)-poly(L-lysine)-lactobionic acid- anti-vascular endothelial growth factor antibody (mPEG-PLGA-PLL-LA/VEGFab or PEAL-LA/VEGFab) nanoparticles (NPs) with highly specific targeting properties as carriers to restore the expression of miR-99a both in vitro and in vivo, to inhibit HCC progression. In vitro, PEAL-LA/VEGFab NPs showed more efficient delivery of miR-99a to HepG2 cells than the conventional transfection reagent Lipofectamine^TM2000 (Lip2000). The higher delivery efficiency associated with PEAL-LA/VEGFab NPs consequently resulted in down-regulation of target genes and suppression of the proliferation, migration and invasion of HepG2 cells. In vivo, miR-99a-PEAL-LA/VEGFab NPs inhibited tumor xenograft growth in HCC-bearing mice without causing obvious systemic toxicity. Our results demonstrate that PEAL-LA/VEGFab NPs selectively and effectively deliver miR-99a to HCC cells based on the double-targeting character of these nanoparticles, thereby offering potential for translation into effective clinical therapies for HCC.

MicroRNA-592 targets IGF-1R to suppress cellular proliferation, migration and invasion in hepatocellular carcinoma

MicroRNAs (miRs) can function as tumor suppressors or oncogenes in different types of human malignancy, and may provide an effective therapy for cancer. The expression and functions of miR-592 have previously been studied in relation to cancer. However, the expression and potential functions of miR-592 in hepatocellular carcinoma (HCC) are still unknown. Using quantitative polymerase chain reaction, MTT assays, cellular migration and invasion assays, bioinformatics software, western blot analysis and dual-luciferase report assays, the present study explored the expression and roles of miR-592 in HCC. It was identified that miR-592 was significantly downregulated in HCC tissues and cell lines. The statistical analysis revealed that low expression of miR-592 was evidently associated with tumor node metastasis stage and lymph node metastasis. Additionally, the present study provided the first evidence that miR-592 was likely to directly target the insulin-like growth factor 1 receptor in vitro. The present results indicated that miR-592 could be investigated as an efficacious therapeutic target for HCC in the future.

MicroRNA-99a inhibits insulin-induced proliferation, migration, dedifferentiation, and rapamycin resistance of vascular smooth muscle cells by inhibiting insulin-like growth factor-1 receptor and mammalian target of rapamycin

Patients with type 2 diabetes mellitus (T2DM) are characterized by insulin resistance and are subsequently at high risk for atherosclerosis. Hyperinsulinemia has been associated with proliferation, migration, and dedifferentiation of vascular smooth muscle cells (VSMCs) during the pathogenesis of atherosclerosis. Moreover, insulin-like growth factor-1 receptor (IGF-1R) and mammalian target of rapamycin (mTOR) have been demonstrated to be the underlying signaling pathways. Recently, microRNA-99a (miR-99a) has been suggested to regulate the phenotypic changes of VSMCs in cancer cells. However, whether it is involved in insulin-induced changes of VSCMs has not been determined. In this study, we found that insulin induced proliferation, migration, and dedifferentiation of mouse VSMCs in a dose-dependent manner. Furthermore, the stimulating effects of high-dose insulin on proliferation, migration, and dedifferentiation of mouse VSMCs were found to be associated with the attenuation of the inhibitory effects of miR-99a on IGF-1R and mTOR signaling activities. Finally, we found that the inducing effect of high-dose insulin on proliferation, migration, and dedifferentiation of VSMCs was partially inhibited by an active mimic of miR-99a. Taken together, these results suggest that miR-99a plays a key regulatory role in the pathogenesis of insulin-induced proliferation, migration, and phenotype conversion of VSMCs at least partly via inhibition of IGF-1R and mTOR signaling. Our results provide evidence that miR-99a may be a novel target for the treatment of hyperinsulinemia-induced atherosclerosis.

MicroRNA-125b-5p mediates post-transcriptional regulation of hepatitis B virus replication via the LIN28B/let-7 axis

MicroRNAs (miRNAs) are able to modulate hepatitis B virus (HBV) replication and play an important role in the pathogenesis of HBV infection. Recently, we have identified that serum miR-125b-5p levels correlated with HBV DNA levels and liver necroinflammation. In the present study, we addressed how miR-125b-5p regulated HBV replication at the different steps, inclduing viral transcription, assembly, and virion production and investigated the underlying mechanisms. We found that miR-125b-5p overexpression increased HBV replication without altering HBV transcription. This is the first demonstration of post-transcriptional miRNA regulation of HBV replication. In contrast, transfection of miR-125b-5p inhibitor resulted in downregulation of HBV replication in hepatoma cells. Further, miR-125b-5p inhibited the phosphorylation of retinoblastoma protein and blocked cell cycle progression at the G1/S phase in hepatoma cell lines. Our results indicate that certain miRNAs are able to arrest the cell cycle at G1 phase and may increase HBV replication. RNA sequencing revealed several liver-specific metabolic pathways regulated by miR-125b-5p, which was also found to suppress LIN28B and induce let-7 family members. Additional data demonstrated that miR-125b-5p targeted the LIN28B/let-7 axis to stimulate HBV replication at a post-transcriptional step.

Emerging Role of MicroRNAs in mTOR Signaling

Mechanistic target of rapamycin (mTOR) is a conserved serine/threonine kinase that plays a critical role in the control of cellular growth and metabolism. Hyperactivation of mTOR pathway is common in human cancers, driving uncontrolled proliferation. MicroRNA (miRNA) is a class of short noncoding RNAs that regulate the expression of a wide variety of genes. Deregulation of miRNAs is a hallmark of cancer. Recent studies have revealed interplays between miRNAs and the mTOR pathway during cancer development. Such interactions appear to provide a fine-tuning of various cellular functions and contribute qualitatively to the behavior of cancer. Here we provide an overview of current knowledge regarding the reciprocal relationship between miRNAs and mTOR pathway: regulation of mTOR signaling by miRNAs and control of miRNA biogenesis by mTOR. Further research in this area may prove important for the diagnosis and therapy of human cancer.

MiR-99a suppresses cell invasion and metastasis in nasopharyngeal carcinoma through targeting HOXA1

Background

Recent studies reported that miRNAs play important roles in the carcinogenesis and progression of nasopharyngeal carcinoma (NPC). Therefore, further studies are warranted to better elucidate the function and mechanism of miRNAs in NPC.

Methods

Quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the miR-99a expression in NPC cell lines and tissue samples. Wound healing, transwell migration and invasion, and lung metastatic colonization assays were performed to determine NPC cell migratory, invasive and metastatic abilities of NPC cells. Luciferase reporter assays, quantitative RT-PCR and Western blotting were used to validate the target of miR-99a.

Results

We found that miR-99a was significantly downregulated in NPC cell lines and tissue samples. Ectopic overexpression of miR-99a significantly inhibited NPC cell migration and invasion in vitro, and suppressed lung macroscopic and microscopic metastatic colonization in vivo. Conversely, silencing of miR-99a significantly promoted the migratory and invasive abilities of NPC cells. Furthermore, HOXA1 was validated as a direct target of miR-99a, and ectopic expression of HOXA1 could rescue the suppressive effect of miR-99a overexpression on NPC cell migration and invasion.

Conclusion

Together, these results indicated that miR-99a could inhibit NPC invasion and metastasis by targeting HOXA1, thus providing a novel potential target for miRNA-based treatment for NPC patients in the future.

Sex and age differences in the expression of liver microRNAs during the life span of F344 rats

Background

Physiological factors such as age and sex have been shown to be risk factors for adverse effects in the liver, including liver diseases and drug-induced liver injury. Previously, we have reported age- and sex-related significant differences in hepatic basal gene expression in rats during the life span that may be related to susceptibility to such adverse effects. However, the underlying mechanisms of the gene expression changes were not fully understood. In recent years, increasing evidence for epigenetic mechanisms of gene regulation has fueled interest in the role of microRNAs (miRNAs) in toxicogenomics and biomarker discovery. We therefore proposed that significant age and sex differences exist in baseline liver miRNA expression, and that comprehensive profiling of miRNAs will provide insights into the epigenetic regulation of gene expression in rat liver.

Methods

To address this, liver tissues from male and female F344 rats were examined at 2, 5, 6, 8, 15, 21, 52, 78, and 104 weeks of age for the expression of 677 unique miRNAs. Following data processing, predictive pathway analysis was performed on selected miRNAs that exhibited prominent age and/or sex differences in expression.

Results

Of the 314 miRNAs found to be expressed, 214 were differentially expressed; 65 and 212 miRNAs showed significant (false discovery rate (FDR) <5% and ≥1.5-fold change) sex- and age-related differences in expression, respectively. Thirty-eight miRNAs showed 2-week-specific expression, of which 31 miRNAs were found to be encoded within the Dlk1-Dio3 cluster located on chromosome 6. This cluster has been associated with tissue proliferation and differentiation, and liver energy homeostasis in postnatal development. Predictive pathway analysis linked sex-biased miRNA expression with sexually dimorphic molecular functions and toxicological functions that may reflect sex differences in hepatic physiology and disease. The expression of miRNAs (miR-18a, miR-99a, and miR-203, miR-451) was also found to associate with specific sexually dimorphic hepatic histopathology. The expression of miRNAs involved in regulating cell death, cell proliferation, and cell cycle was found to change as the rats matured from adult to old age.

Conclusions

Overall, significant age- and sex-related differences in liver miRNA expression were identified and linked to histopathological findings and predicted functional pathways that may underlie susceptibilities to liver toxicity and disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s13293-017-0127-9) contains supplementary material, which is available to authorized users.

Viral hemorrhagic septicemia virus (VHSV) infection-mediated sequential changes in microRNAs profile of Epithelioma papulosum cyprini (EPC) cells

MicroRNAs are small non-coding RNAs and are involved in the regulation of wide biological processes. Viral hemorrhagic septicemia virus (VHSV) is the causative agent of viral hemorrhagic septicemia (VHS) disease causing a heavy loss in aquaculture farms. In this study, we tried to explore the effect of VHSV infection on microRNAs profile of Epithelioma papulosum cyprini (EPC) cells at different points of time (0, 3, 12, 24, and 48 h post infection). A total of 355 conserved microRNAs and 3 novel microRNAs were identified, and among them, 103 microRNAs were differentially expressed. The number of differentially expressed microRNAs was highly increased at 24 h.p.i compared to 3 h.p.i and 12 h.p.i., suggesting that EPC cells might not actively respond to VHSV infection at an early infection period, which can allow viruses to transcript and translate their genes enough to produce viral particles that can infect to another cells. Among the differentially expressed microRNAs, 2 miRNAs (miR-735 and miR-738) that were reported only in fish species were highly upregulated, and based on the target prediction, they could regulate several immune pathways. Furthermore, the present results showed the upregulation of representative immune regulating microRNAs such as miR-146a, miR-155, and miR-99. The target prediction of differentially expressed miRNAs, GO, and KEGG pathways analysis revealed that several biological processes and different pathways were affected by the viral infection. The present dynamical changing patterns of differentially expressed microRNAs in response to the progression of VHSV infection suggest that microRNA profile that was analyzed at one time point cannot provide enough information for the interpretation of the disease mechanism. Considering the wide and complex interactions between microRNAs and genes expression, the present results provide the basis for the understanding of VHSV infection-mediated cellular responses and for future investigations on the development of possible control measures.

WITHDRAWN: MicroRNA-99a Suppresses Proliferation, Migration, Invasion and Induces G1-phase Cell Cycle Arrest via Targeting Insulin-like Growth Factor 1 Receptor Pathway in Renal Cell Carcinoma 786-0 and OS-RC-2 Cells

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The microRNA-99 family modulates hepatitis B virus replication by promoting IGF-1R/PI3K/Akt/mTOR/ULK1 signaling-induced autophagy

MicroRNAs are small highly conserved noncoding RNAs that are widely expressed in multicellular organisms and participate in the regulation of various cellular processes including autophagy and viral replication. Evidently, microRNAs are able to modulate host gene expression and thereby inhibit or enhance hepatitis B virus (HBV) replication. The miR-99 family members are highly expressed in the liver. Interestingly, the plasma levels of miR-99 family in the peripheral blood correspond with HBV DNA loads. Thus, we asked whether the miR-99 family regulated HBV replication and analyzed the underlying molecular mechanism. Compared with primary hepatocytes, miR-99 family expression was downregulated in hepatoma cells. Transfection of miR-99a, miR-99b, and miR-100 markedly increased HBV replication, progeny secretion, and antigen expression in hepatoma cells. However, miR-99 family had no effect on HBV transcription and HBV promoter activities, suggesting that they regulate HBV replication at posttranscriptional steps. Consistent with bioinformatic analysis and recent reports, ectopic expression of miR-99 family attenuated IGF-1R/Akt/mTOR pathway signaling and repressed insulin-stimulated activation in hepatoma cells. Moreover, the experimental data demonstrated that the miR-99 family promoted autophagy through mTOR/ULK1 signaling and thereby enhanced HBV replication. In conclusion, the miR-99 family promotes HBV replication posttranscriptionally through IGF-1R/PI3K/Akt/mTOR/ULK1 signaling-induced autophagy.

Hepatoepigenetic Alterations in Viral and Nonviral-Induced Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a major public health concern and one of the leading causes of tumour-related deaths worldwide. Extensive evidence endorses that HCC is a multifactorial disease characterised by hepatic cirrhosis mostly associated with chronic inflammation and hepatitis B/C viral infections. Interaction of viral products with the host cell machinery may lead to increased frequency of genetic and epigenetic aberrations that cause harmful alterations in gene transcription. This may provide a progressive selective advantage for neoplastic transformation of hepatocytes associated with phenotypic heterogeneity of intratumour HCC cells, thus posing even more challenges in HCC treatment development. Epigenetic aberrations involving DNA methylation, histone modifications, and noncoding miRNA dysregulation have been shown to be intimately linked with and play a critical role in tumour initiation, progression, and metastases. The current review focuses on the aberrant hepatoepigenetics events that play important roles in hepatocarcinogenesis and their utilities in the development of HCC therapy.

Biomarker MicroRNAs for Diagnosis, Prognosis and Treatment of Hepatocellular Carcinoma: A Functional Survey and Comparison

Hepatocellular Carcinoma (HCC) is one of the most common malignant tumors with high incidence and mortality rate. Precision and effective biomarkers are therefore urgently needed for the early diagnosis and prognostic estimation. MicroRNAs (miRNAs) are important regulators which play functions in various cellular processes and biological activities. Accumulating evidence indicated that the abnormal expression of miRNAs are closely associated with HCC initiation and progression. Recently, many biomarker miRNAs for HCC have been identified from blood or tissues samples, however, the universality and specificity on clinicopathological features of them are less investigated. In this review, we comprehensively surveyed and compared the diagnostic, prognostic, and therapeutic roles of HCC biomarker miRNAs in blood and tissues based on the cancer hallmarks, etiological factors as well as ethnic groups, which will be helpful to the understanding of the pathogenesis of biomarker miRNAs in HCC development and further provide accurate clinical decisions for HCC diagnosis and treatment.

miR-96, miR-145 and miR-9 expression increases, and IGF-1R and FOXO1 expression decreases in peripheral blood mononuclear cells of aging humans

Background

In mammals, the IGF-1 pathway affects the phenotype of aging. Since the function of the immune system is modulated by IGF-1, it is plausible that immunosenescence might in part result from altered control by this pathway. We therefore examined whether the expression of IGF-1R, FOXO1, and FOXO3a in peripheral blood mononuclear cells (PBMC) changes with age and if this might be due to changes in the expression of select miRNAs.

Methods

The expression of IGF-1R, FOXO1, FOXO3a, as well as of miR-9, miR-96, miR-99a, miR-132, miR-145, and miR-182 was examined in PBMC of young (27.8 ± 3.7 years), elderly (65.6 ± 3.4 years), and long-lived (94.0 ± 3.7 years) Polish Caucasians using real-time PCR. mRNA/miRNA interactions were studied in HEK 293 cells using luciferase-expressing pmirGLO reporter vector.

Results

The median expression of IGF-1R decreased with age (p < 0.000001), as did the expression of FOXO1 (p < 0.000001), while the expression of FOXO3a remained stable. We also found an age-associated increase of the median expression of miR-96 (p = 0.002), miR-145 (p = 0.024) and miR-9 (p = 0.026), decrease of the expression of miR-99a (p = 0.037), and no changes regarding miR-132 and miR-182. Functional studies revealed that miR-96 and miR-182 interacted with human IGF-1R mRNA, and that miR-145 and miR-132 interacted with human FOXO1 mRNA.

Conclusions

The age-associated higher expression of miR-96 and miR-145 might contribute to the lower expression of IGF-1R while the higher expression of miR-96, miR-145 and miR-9 might contribute to the lower expression of FOXO1 in peripheral blood mononuclear cells of aging humans. Sustained expression/function of FOXO3a but not of the other two genes might be important for the maintenance of the immune system function in these individuals.

Insights for hepatitis C virus related hepatocellular carcinoma genetic biomarkers: Early diagnosis and therapeutic intervention

The current review explores the role of emerging molecular contributing factors in liver carcinogenesis on top of hepatitis C virus (HCV). Here we will try to discuss the role genetic and epigenetic factors in pathogenesis of hepatocellular carcinoma. Understanding the role of these factors will help in discovering the mystery of liver carcinogenesis on top of chronic HCV infection. Moreover, use of the studied molecular factors will provide the hepatologists with tailored diagnostic promising biomarkers and flatten the way for establishment of emerging molecular treatment based on exploring the molecular subscription of this aggressive liver cancer.

MiR-940 Inhibited Cell Growth and Migration in Triple-Negative Breast Cancer

BACKGROUND Breast cancer is the main type of cancer in women, and triple-negative breast cancer (TNBC) is a unique subtype of breast cancer. The expression of miR-940 has been shown to play an important role in various cancers; however, the role of miR-940 in TNBC remains unknown. MATERIAL AND METHODS The expression of miR-940 in TNBC tissues or cells were tested by qRT-PCR; the expression of miR-940 in cells were overexpressed by miR-940 mimics, and suppressed by anti-miR-940. Bioinformatics algorithms from TargetScanHuman were used to predict the target genes of miR-940. The interaction between miR-940 and ZNF24 was confirmed by dual luciferase assays. The protein level was assayed by Western blot. RESULTS TNBC tissues and cells showed lower miR-940 levels. CONCLUSIONS MiR-940 inhibited cellular proliferation and migration in TNBC.

MicroRNA-99a inhibits tumor aggressive phenotypes through regulating HOXA1 in breast cancer cells

MicroRNAs (miRNAs) are key regulators of tumor progression. Based on microarray data, we identified miR-99a as a potential tumor suppressor in breast cancer. Expression of miR-99a is frequently down-regulated in breast cancer tissues relative to normal breast tissues. Reduced miR-99a expression was highly associated with lymph node metastasis and shorter overall survival of patients with breast cancer. Gain- and loss-of-function studies revealed that, miR-99a significantly inhibits breast cancer cell proliferation, migration, and invasion. An integrated bioinformatics analysis identified HOXA1 mRNA as the direct functional target of miR-99a, and this regulation was confirmed by luciferase reporter assay. Furthermore, we showed for the first time that HOXA1 expression is elevated in breast cancer tissues. Knockdown of HOXA1 significantly inhibited breast cancer cell proliferation, migration and invasion, and restoration of HOXA1 partially rescued the inhibitory effect of miR-99a in breast cancer cells. Collectively, our data indicate that miR-99a plays a tumor-suppressor role in the development of breast cancer, and could serve as a potential therapeutic target for breast cancer treatment.

Integrative analysis of transcriptome and miRNome unveils the key regulatory connections involved in different stages of hepatocellular carcinoma

Dysregulated molecular processes are the major factors that drive and feed the signaling processes involved in carcinogenesis. In recent years, regulation of mRNAs by microRNAs (miRNAs) has been found to play a vital role in many cancers including hepatocellular carcinoma (HCC). However, genomewide studies defining molecular regulatory circuits at both mRNA and miRNA levels are just emerging. To uncover the molecular and functional processes involved in liver tumorigenesis at mRNA and miRNA level, a co-expression-based network of miRNAs was constructed from multiple miRNA profiles. The applicability of the network approach to microRNA expression profiles was assessed. Although the clustering consistency of miRNAs across the profiles was found moderate, miRNA networking has been found informative. Furthermore, microRNA network modules were integrated with the functionally defined mRNA modules derived from an mRNA co-expression network of an earlier study. Three highly clustered regulatory circuits of mRNA-miRNA modules have been identified as involved in hepatocyte, inflammatory-stress and proliferative process activated subcategories of HCC. A subset of the proliferative miRNA module was found clustered in the 14q32.31 chromosomal region. The current integrative network analysis of mRNA-miRNA modules shows the intricate miRNA-mRNA functional circuits and signaling interactions involved in liver tumorigenesis.

MicroRNA-486-5p enhances hepatocellular carcinoma tumor suppression through repression of IGF-1R and its downstream mTOR, STAT3 and c-Myc

The insulin-like growth factor (IGF)-axis has been paradigmatically involved in hepatocellular carcinoma (HCC) tumor initiation, progression and drug resistance. Consequently, members of the IGF-axis and most importantly, IGF-1 receptor (IGF-1R) have been considered as intriguing targets for HCC therapy. Few miRNAs have been recently reported to be associated with IGF-1R regulation. The present study aimed to investigate the role of microRNA (miRNA/miR)-486-5p in the regulation of IGF-1R and its downstream signaling cascades. miR-486-5p was markedly downregulated in hepatitis C virus-induced HCC tissues and Huh-7 cells. Forcing the expression of miR-486-5p in Huh-7 cells resulted in the repression of IGF-1R, mammalian target of rapamycin (mTOR), signal transducer and activator of transcription 3 (STAT3) and c-Myc mRNA levels. Ectopic expression of miR-486-5p in Huh-7 cells markedly repressed cellular viability, proliferation, migration and clonogenicity in a similar pattern to IGF-1R small interfering RNAs, and were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, BrdU incorporation, wound healing and colony forming assays, respectively. Overall, the study findings demonstrated that miR-486-5p acts as a tumor suppressor in HCC through the repression of essential members of the IGF-axis, including IGF-1R and its downstream mediators mTOR, STAT3 and c-Myc.

MiR-1 downregulation correlates with poor survival in clear cell renal cell carcinoma where it interferes with cell cycle regulation and metastasis

MicroRNAs (miRNA) that are strongly implicated in carcinogenesis have recently reshaped our understanding of the role of noncoding RNAs. Here, we focused on the function and molecular mechanism of miR-1 and its potential clinical application in clear cell renal cell carcinoma (ccRCC). First, miR-1 was significantly downregulated in 87.8% renal cancer samples compared with corresponding noncancerous tissues (NCT), which was significantly associated with clinical stage, T classification and poor overall survival. Functional study demonstrated that enforced overexpression of miR-1 in renal cancer cells inhibited proliferation and metastasis in vitro and in vivo. Conversely, miR-1 inhibitor silencing miR-1 expression promoted cell proliferation and metastasis in ccRCC. CDK4, CDK6, Caprin1 and Slug were each directly targeted for inhibition by miR-1 and restoring their expression reversed miR-1-mediated inhibition of cell cycle progression and metastasis. Taken together, our findings established a tumor suppressive role for miR-1 in the progression of ccRCC by targeting CDK4, CDK6, Caprin1 and Slug and suggested miR-1 can be served as a novel potential therapeutic target for ccRCC.

MiR-99a Inhibits Cell Proliferation and Tumorigenesis through Targeting mTOR in Human Anaplastic Thyroid Cancer

MicroRNAs (miRNAs) are emerging as critical regulators in carcinogenesis and tumor progression. Recently, miR-99a has been reported as a tumor suppressor gene in various human cancers, but its functions in the context of anaplastic thyroid cancer (ATC) remain unknown. In this study, we reported that miR-99a was commonly downregulated in ATC tissue specimens and cell lines with important functional consequences. Overexpression of miR-99a not only dramatically reduced ATC cell viability by inducing cell apoptosis and accumulation of cells at G1 phase, but also inhibited tumorigenicity in vivo. We then screened and identified a novel miR-99a target, mammalian target of rapamycin (mTOR), and it was further confirmed by luciferase assay. Up-regulation of miR-99a would markedly reduce the expression of mTOR and its downstream phosphorylated proteins (p-4E- BP1 and p-S6K1). Similar to restoring miR-99a expression, mTOR down-regulation suppressed cell viability and increased cell apoptosis, whereas restoration of mTOR expression significantly reversed the miR-99a antitumor activity and the inhibition of mTOR/p-4E-BP1/p-S6K1 signal pathway profile. In clinical specimens and cell lines, mTOR was commonly overexpressed and its protein levels were statistically inversely correlated with miR-99a expression. Taken together, our results demonstrated for the first time that miR-99a functions as a tumor suppressor and plays an important role in inhibiting the tumorigenesis through targeting the mTOR/p- 4E-BP1/p-S6K1 pathway in ATC cells. Given these, miR-99a may serve as a novel prognostic/diagnostic and therapeutic target for treating ATC.

Aberrant expression of microRNA-99a and its target gene mTOR associated with malignant progression and poor prognosis in patients with osteosarcoma

Background

The mammalian target of rapamycin (mTOR) has been reported to act as a target gene of microRNA (miR)-99a in various cancer cells and identified as an independent prognostic marker of human osteosarcoma. The aim of this study was to investigate the clinical significance of miR-99a/mTOR axis in human osteosarcoma.

Methods

A total of 130 pairs of osteosarcoma and matched noncancerous bone tissues were used to detect the expression levels of miR-99a and mTOR mRNA by quantitative real-time polymerase chain reaction. Then, associations of miR-99a and/or mTOR expression with clinico-pathological features and prognosis of patients with osteosarcoma were statistically analyzed.

Results

The expression levels of miR-99a (tumor vs normal: 2.11±1.03 vs 4.69±1.21, P<0.001) and mTOR mRNA (tumor vs normal: 4.40±1.13 vs 1.74±0.85, P<0.001) in osteosarcoma tissues were, respectively, lower and higher than those in noncancerous bone tissues. The expression levels of miR-99a in osteosarcoma tissues were negatively correlated with those of mTOR mRNA. Additionally, miR-99a-low and/or mTOR-high expression were all significantly associated with advanced surgical stage, positive metastasis and recurrence, and poor response to chemotherapy (all P<0.05). Moreover, patients with osteosarcoma with miR-99a-low and/or mTOR-high expression had shorter overall and disease-free survivals than those in miR-99a-high and/or mTOR-low expression groups. Multivariate Cox analyses showed that miR-99a and/or mTOR expression were all independent prognostic factors of osteosarcoma.

Conclusion

Our data showed the crucial role of miR-99a/mTOR axis in the malignant progression of human osteosarcoma, implying that conjoined expression of miR-99a and mTOR may offer an attractive novel prognostic marker for this disease.