Downregulation of miR-101-3p by hepatitis B virus promotes proliferation and migration of hepatocellular carcinoma cells by targeting Rab5a

Non-coding ribonucleic acid-mediated CAMSAP1 upregulation leads to poor prognosis with suppressed immune infiltration in liver hepatocellular carcinoma

Liver hepatocellular carcinoma (LIHC) is well-known for its unfavorable prognosis due to the lack of reliable diagnostic and prognostic biomarkers. Calmodulin-regulated spectrin-associated protein 1 (CAMSAP1) is a non-centrosomal microtubule minus-end binding protein that regulates microtubule dynamics. This study aims to investigate the specific role and mechanisms of CAMSAP1 in LIHC. We performed systematical analyses of CAMSAP1 and demonstrated that differential expression of CAMSAP1 is associated with genetic alteration and DNA methylation, and serves as a potential diagnostic and prognostic biomarker in some cancers, especially LIHC. Further evidence suggested that CAMSAP1 overexpression leads to adverse clinical outcomes in advanced LIHC. Moreover, the AC145207.5/LINC01748-miR-101–3p axis is specifically responsible for CAMSAP1 overexpression in LIHC. In addition to the previously reported functions in the cell cycle and regulation of actin cytoskeleton, CAMSAP1-related genes are enriched in cancer- and immune-associated pathways. As expected, CAMSAP1-associated LIHC is infiltrated in the suppressed immune microenvironment. Specifically, except for immune cell infiltration, it is significantly positively correlated with immune checkpoint genes, especially CD274 (PD-L1), and cancer-associated fibroblasts. Prediction of immune checkpoint blockade therapy suggests that these patients may benefit from therapy. Our study is the first to demonstrate that besides genetic alteration and DNA methylation, AC145207.5/LINC01748-miR-101-3p-mediated CAMSAP1 upregulation in advanced LIHC leads to poor prognosis with suppressed immune infiltration, representing a potential diagnostic and prognostic biomarker as well as a promising immunotherapy target for LIHC.

Receptors for Respiratory Syncytial Virus Infection and Host Factors Regulating the Life Cycle of Respiratory Syncytial Virus

Respiratory syncytial virus (RSV) is a common cause of lower respiratory tract infections and responsible for a large proportion of mortality in children and the elderly. There are no licensed vaccines available to date. Prophylaxis and therapeutic RSV-specific antibodies are limited to populations at high risk owing to high cost and uncertain clinical value. Receptors and host factors are two determinants important for virus entry and establishment of infection in vivo. The identification and understanding of viral receptors and host factors can help us to gain insight into the pathogenesis of RSV infection. Herein, we reviewed receptors and host factors that have been reported thus far. RSV could bind to CX3C chemokine receptor 1 and heparan sulfate proteoglycans via the G protein, and to nucleolin, insulin-like growth factor-1 receptor, epidermal growth factor, and intercellular adhesion molecule-1 via the F protein. Seven host restriction factors and 13 host factors essential for RSV infection were reviewed. We characterized the functions and their roles in the life cycle of RSV, trying to provide an update on the information of RSV-related receptors and host factors.

Role of Rab GTPases in Hepatocellular Carcinoma

The Rab GTPase family contains almost 70 genes in the human genome and acts as the key regulator of intracellular membrane trafficking in human cells. The dysregulation of Rab GTPase has been shown to be associated with multiple human diseases, ranging from neurodegeneration, and infection to cancer. Rab GTPases not only play important roles in genome replication, morphogenesis and the release of hepatitis B virus (HBV) or hepatitis C virus (HCV), but also contribute to hepatitis-related hepatocarcinogenesis and hepatocellular carcinoma (HCC) progression. The alteration of Rab GTPase expression in HCC plays an important role in tumour cell proliferation, invasion and migration. Notably, the expression of Rab genes can be regulated by some noncoding RNAs, such as miRNAs and circRNAs. Thus, Rab GTPases can serve as promising rational and therapeutic targets for HCC treatments. In this review, we summarized recent advancements in this field focusing on Rab GTPases in HCC.

Autophagy Modulation by Viral Infections Influences Tumor Development

Autophagy is a self-degradative process important for balancing cellular homeostasis at critical times in development and/or in response to nutrient stress. This is particularly relevant in tumor model in which autophagy has been demonstrated to have an important impact on tumor behavior. In one hand, autophagy limits tumor transformation of precancerous cells in early stage, and in the other hand, it favors the survival, proliferation, metastasis, and resistance to antitumor therapies in more advanced tumors. This catabolic machinery can be induced by an important variety of extra- and intracellular stimuli. For instance, viral infection has often been associated to autophagic modulation, and the role of autophagy in virus replication differs according to the virus studied. In the context of tumor development, virus-modulated autophagy can have an important impact on tumor cells' fate. Extensive analyses have shed light on the molecular and/or functional complex mechanisms by which virus-modulated autophagy influences precancerous or tumor cell development. This review includes an overview of discoveries describing the repercussions of an autophagy perturbation during viral infections on tumor behavior.

Respiratory syncytial virus activates Rab5a to suppress IRF1-dependent IFN-λ production, subverting the antiviral defense of airway epithelial cells

The limited antiviral options and lack of an effective vaccine against human respiratory syncytial virus (RSV) highlight the need for a novel antiviral therapy. One alternative is to identify and target the host factors required for viral infection. Here, using RNA interference to knock down Rab proteins, we provide multiple lines of evidence that Rab5a is required for RSV infection: (a) Rab5a is upregulated both in RSV-A2-infected A549 cells and RSV-A2-challenged BALB/c mice's airway epithelial cells at early infection phase; (b) shRNA-mediated knockdown of Rab5a is associated with reduced lung pathology in RSV A2 challenged mice; (c) Rab5a expression is correlated with disease severity of RSV infection of infants. Knockdown of Rab5a increases IFN-λ (lambda) production by mediating IRF1 nuclear translocation. Our results highlight a new role for Rab5a in RSV infection, such that its depletion inhibits RSV infection by stimulating the endogenous respiratory epithelial antiviral immunity, which suggests that Rab5a is a potential target for novel therapeutics against RSV infection.Importance This study highlights the important role of Rab5a in RSV infection, such that its depletion inhibits RSV infection by stimulating the endogenous respiratory epithelial antiviral immunity and attenuates inflammation of the airway, which suggests that Rab5a is a powerful potential target for novel therapeutics against RSV infection.

Cell death pathways and viruses: Role of microRNAs

Viral infections lead to the death of more than a million people each year around the world, both directly and indirectly. Viruses interfere with many cell functions, particularly critical pathways for cell death, by affecting various intracellular mediators. MicroRNAs (miRNAs) are a major example of these mediators because they are involved in many (if not most) cellular mechanisms. Virus-regulated miRNAs have been implicated in three cell death pathways, namely, apoptosis, autophagy, and anoikis. Several molecules (e.g., BECN1 and B cell lymphoma 2 [BCL2] family members) are involved in both apoptosis and autophagy, while activation of anoikis leads to cell death similar to apoptosis. These mechanistic similarities suggest that common regulators, including some miRNAs (e.g., miR-21 and miR-192), are involved in different cell death pathways. Because the balance between cell proliferation and cell death is pivotal to the homeostasis of the human body, miRNAs that regulate cell death pathways have drawn much attention from researchers. miR-21 is regulated by several viruses and can affect both apoptosis and anoikis via modulating various targets, such as PDCD4, PTEN, interleukin (IL)-12, Maspin, and Fas-L. miR-34 can be downregulated by viral infection and has different effects on apoptosis, depending on the type of virus and/or host cell. The present review summarizes the existing knowledge on virus-regulated miRNAs involved in the modulation of cell death pathways. Understanding the mechanisms for virus-mediated regulation of cell death pathways could provide valuable information to improve the diagnosis and treatment of many viral diseases.

MicroRNA-101-3p inhibits fibroblast-like synoviocyte proliferation and inflammation in rheumatoid arthritis by targeting PTGS2

OBJECTIVE

Rheumatoid arthritis (RA) is the most frequently occurring inflammatory arthritis. The present study was performed to characterize the role of microRNA-101-3p (miR-101-3p) and prostaglandin-endoperoxide synthase 2 (PTGS2) in inflammation and biological activities of fibroblast-like synoviocytes (FLSs) in RA.

METHODS

Initially, miR-101-3p and PTGS2 expression in RA tissues of RA patients and RA rats was detected by qRT-PCR and Western blot analysis. Rat model of type II collagen-induced arthritis (CIA) was adopted to simulate RA, followed by injection of miR-101-3p mimics or siRNA against PTGS2. Next, the apoptosis in synovial tissue and the levels of tumor necrosis factor (TNF)-α, IL-1β and IL-6 were identified. Subsequently, FLSs in RA (RA-FLSs) were isolated, after which in vitro experiments were conducted to analyze cell proliferation, apoptosis, migration and invasion upon treatment of up-regulated miR-101-3p and silenced PTGS2. Furthermore, the relationship of miR-101-3p and PTGS2 was determined by bioinformatics prediction and luciferase activity assay.

RESULTS

We identified poorly expressed miR-101-3p and highly expressed PTGS2 in synovial tissues of RA patients and RA rats, which showed reduced synoviocyte apoptosis and enhanced inflammation. In response to miR-101-3p mimics and si-PTGS2, the RA-FLSs were observed with attenuated cell proliferation, migration and invasion, corresponding to promoted apoptosis. Down-regulation of PTGS2 could rescue the effect of inhibited miR-101-3p in synovial injury and phenotypic changes of FLS in RA rats. Notably, miR-101-3p was found to negatively regulate PTGS2.

CONCLUSION

Taken together, miR-101-3p reduces the joint swelling and arthritis index in RA rats by down-regulating PTGS2, as evidenced by inhibited FLS proliferation and inflammation.

Dysregulated microRNAs in Hepatitis B Virus-Related Hepatocellular Carcinoma: Potential as Biomarkers and Therapeutic Targets

MicroRNAs (miRNAs) are non-coding small RNAs that can function as gene regulators and are involved in tumorigenesis. We review the commonly dysregulated miRNAs in liver tumor tissues and plasma/serum of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) patients. The frequently reported up-regulated miRNAs in liver tumor tissues include miR-18a, miR-21, miR-221, miR-222, and miR-224, whereas down-regulated miRNAs include miR-26a, miR-101, miR-122, miR-125b, miR-145, miR-199a, miR-199b, miR-200a, and miR-223. For a subset of these miRNAs (up-regulated miR-222 and miR-224, down-regulated miR-26a and miR-125b), the pattern of dysregulated circulating miRNAs in plasma/serum is mirrored in tumor tissue based on multiple independent studies. Dysregulated miRNAs target oncogenes or tumor suppressor genes involved in hepatocarcinogenesis. Normalization of dysregulated miRNAs by up- or down-regulation has been shown to inhibit HCC cell proliferation or sensitize liver cancer cells to chemotherapeutic treatment. miRNAs hold as yet unrealized potential as biomarkers for early detection of HCC and as precision therapeutic targets, but further studies in diverse populations and across all stages of HCC are needed.

miRNA‑101‑3p.1 as an independent diagnostic biomarker aggravates chronic obstructive pulmonary disease via activation of the EGFR/PI3K/AKT signaling pathway

Exploring independent biomarkers and delineating pathogenic mechanisms could improve the early diagnosis and treatment of chronic obstructive pulmonary disease (COPD). In the present study, a study was conducted to determine the diagnostic potential of miRNA‑101‑3p.1 in identifying stable COPD (SCOPD) and acute exacerbation of COPD (AECOPD) patients and to reveal the molecular mechanism by which miRNA‑101‑3p.1 regulates COPD progression. miRNA‑101‑3p.1 profiles in peripheral blood mononuclear cells of COPD patients were evaluated. Subsequently, receiver operating characteristic curves were created to demonstrate the diagnostic accuracy of miRNA‑101‑3p.1 in discriminating SCOPD and AECOPD. Finally, the molecular mechanism by which miRNA‑101‑3p.1 regulates COPD progression was explored. The present study revealed that patients with COPD, and especially patients with AECOPD, had significantly increased levels of miRNA‑101‑3p.1 and the level of miRNA‑101‑3p.1 was closely correlated with CAT score and FEV1% predicted. Notably, miRNA‑101‑3p.1 accurately discriminated SCOPD and AECOPD. Furthermore, increasing miRNA‑101‑3p.1 promoted cell proliferation and induced the expression of inflammatory cytokines. Mechanistic investigations revealed that miRNA‑101‑3p.1 inhibited the expression of von Hippel‑Lindau tumor suppressor (pVHL) and ubiquitin conjugating enzyme E2 D1 (UBE2D1). pVHL and UBE2D1 co‑upregulated HIF‑1α, and HIF‑1α mediated activation of the EGFR/PI3K/AKT signaling pathway. The present results collectively demonstrated that miRNA‑101‑3p.1 could act as an independent biomarker for the diagnosis of SCOPD and AECOPD, and that miRNA‑101‑3p.1 facilitates COPD progression by activating the EGFR/PI3K/AKT signaling pathway.

Exosomes derived from microRNA-101-3p-overexpressing human bone marrow mesenchymal stem cells suppress oral cancer cell proliferation, invasion, and migration

Dysregulation of microRNAs (miRNAs) has been found to disrupt the progression of oral cancer. However, which miRNAs are most effective against oral cancer and how these miRNAs should be delivered are major unanswered problems. We aimed at investigating if human bone marrow mesenchymal stem cells (hBMSCs)-derived exosomes affect oral cancer development, and the potential regulatory mechanism associated with COL10A1 and miR-101-3p. COL10A1 was upregulated, while miR-101-3p was downregulated in oral cancer, and miR-101-3p targeted COL10A1 as verified by dual-luciferase reporter gene assay. Meanwhile, exosomes derived from hBMSCs were isolated and then co-cultured with oral cancer cells to identify the role of exosomes, and the results suggested that hBMSCs-derived exosomes overexpressing miR-101-3p inhibited oral cancer progression. Furthermore, tumorigenicity assay in nude mice further confirmed the inhibitory effects of hBMSCs-derived exosomes, loaded with miR-101-3p, on oral cancer, which provides a new theoretical basis in the treatment of oral cancer.

Identification of potential microRNA markers related to Crimean-Congo hemorrhagic fever disease

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease caused by the arbovirus Crimean-Congo hemorrhagic fever virus (CCHFV). The CCHFV has a single-stranded RNA genome of negative sense. MicroRNAs (miRNAs) are key players in virus-host interactions and viral pathogenesis. We investigated the miRNA gene expression profiles in patients with CCHF using microarray for the first time in the world. Microarray analysis was performed using mirBase Ver 21 (Agilent Technologies, Santa Clara, CA). All statistical analyses were performed across the case-control, fatal-control, and fatal-nonfatal case groups using Genespring (Ver 3.0). Fifteen miRNAs were statistical significant in patients with CCHF compared with the controls (5 were upregulated, 10 were downregulated). Seventy-five and sixty-six miRNAs are in fatal compared with control and nonfatal case, respectively (fold change ([FC] ≥50) were statistically significant. In this study, the target genes of important miRNAs were identified and Gene Ontology analyses were performed across all groups. As a result of this study, we propose that the detection of miRNAs in patients with CCHF will allow the determination of therapeutic targets in diseases. CCHF is an important public health problem that can often be fatal. In this study, we investigated miRNA expression in case-control, fatal-control, and fatal-nonfatal case groups. Significant miRNAs associated with fatality were detected in CCHF. This study will serve as a source of data for the development of an antagomir-based therapy against CCHF using miRNAs in the future.

miR-101 regulates cell proliferation and apoptosis by targeting KDM1A in diffuse large B cell lymphoma

Background

miR-101 is reported to be associated with cell proliferation and apoptosis. However, it is unknown whether miR-101 expression affects cell proliferation and apoptosis in diffuse large B cell lymphoma (DLBCL). The aim of the present study was to investigate the expression of miR-101 and its effect on cell proliferation and apoptosis in DLBCL.

Methods

miR-101 expression was detected in 30 cases of patients with DLBCL and normal lymph node by qRT-PCR. Then, miR-101 expression was up-regulated and down-regulated in Originated Cell Line-Large Lymphoma 8 (OCL-LY8) cell line, respectively. MTT and flow cytometry assay were used to evaluate the effect of miR-101 on cell proliferation and apoptosis, respectively. As KDM1A was confirmed to be as a specific target of miR-101 by TargetScanHuman, the relationship between MiR-101 and KDM1A was further investigated.

Results

miR-101 expression in patients with DLBCL was significantly reduced compared those in normal lymph node (P<0.05). miR-101 expression was significantly associated with tumor size, clinical stage and International Prognostic Index (IPI) scores (P<0.05). In OCL-LY8 cell line, miR-101 down-regulation significantly promoted cell proliferation and suppressed cell apoptosis. Meanwhile, miR-101 up-regulation reversed this effect. In addition, miR-101 negatively regulated the expression of KDM1A. KDM1A down-regulation was oberved in normal tissues compared with those in DLBCL tissues, which inhibited cell proliferation and promoted cell apoptosis.

Conclusion

These data indicate that miR-101 regulates cell proliferation and apoptosis by targeting KDM1A, which provides a potential therapeutic for DLBCL patients.

Molecular Mechanisms Driving Progression of Liver Cirrhosis towards Hepatocellular Carcinoma in Chronic Hepatitis B and C Infections: A Review

Almost all patients with hepatocellular carcinoma (HCC), a major type of primary liver cancer, also have liver cirrhosis, the severity of which hampers effective treatment for HCC despite recent progress in the efficacy of anticancer drugs for advanced stages of HCC. Here, we review recent knowledge concerning the molecular mechanisms of liver cirrhosis and its progression to HCC from genetic and epigenomic points of view. Because ~70% of patients with HCC have hepatitis B virus (HBV) and/or hepatitis C virus (HCV) infection, we focused on HBV- and HCV-associated HCC. The literature suggests that genetic and epigenetic factors, such as microRNAs, play a role in liver cirrhosis and its progression to HCC, and that HBV- and HCV-encoded proteins appear to be involved in hepatocarcinogenesis. Further studies are needed to elucidate the mechanisms, including immune checkpoints and molecular targets of kinase inhibitors, associated with liver cirrhosis and its progression to HCC.

Molecular Mechanisms Driving Progression of Liver Cirrhosis towards Hepatocellular Carcinoma in Chronic Hepatitis B and C Infections: A Review

Almost all patients with hepatocellular carcinoma (HCC), a major type of primary liver cancer, also have liver cirrhosis, the severity of which hampers effective treatment for HCC despite recent progress in the efficacy of anticancer drugs for advanced stages of HCC. Here, we review recent knowledge concerning the molecular mechanisms of liver cirrhosis and its progression to HCC from genetic and epigenomic points of view. Because ~70% of patients with HCC have hepatitis B virus (HBV) and/or hepatitis C virus (HCV) infection, we focused on HBV- and HCV-associated HCC. The literature suggests that genetic and epigenetic factors, such as microRNAs, play a role in liver cirrhosis and its progression to HCC, and that HBV- and HCV-encoded proteins appear to be involved in hepatocarcinogenesis. Further studies are needed to elucidate the mechanisms, including immune checkpoints and molecular targets of kinase inhibitors, associated with liver cirrhosis and its progression to HCC.

Effects of miR-101, miR-345 on HBV replication regulation and on the growth of liver cancer cells

The aim of the study was to investigate the effects of miRNA-101 and miRNA-345 on HBV replication and liver cancer cell growth. qPCR was performed to detect the expression of miRNA-101 and miRNA-345. The expression of HBV RNA was detected by PCR. The expression of HbsAg was detected using ELISA. BEL-7404 cell line proliferation was detected by MTT assay. The expression levels of miR-101 and miR-345 in BEL-7404 pSUPER.neo-miR-101 group and BEL-7404 pSUPER.neo-miR-345 group were significantly higher than those in BEL-7404 pSUPER.neo group (P<0.05). The expression levels of miR-101 and miR-345 in MHCC97-L pSUPER.neo-miR-101 group and MHCC97-L pSUPER.neo-miR-345 group were significantly higher than those in MHCC97-L pSUPER.neo group (P<0.05). The expression of HBV DNA in MHCC97-L pSUPER.neo-miR-101 group was significantly lower than that in MHCC97-L pSUPER.neo group (P<0.05), and the expression of HBV DNA in MHCC97-L pSUPER.neo-miR-345 group was significantly higher than that in MHCC97-L pSUPER.neo group (P<0.05). The expression of HbsAg in MHCC97-L pSUPER.neo-miR-101 group was significantly lower than that in MHCC97-L pSUPER.neo group (P<0.05), and the expression of HbsAg in MHCC97-L pSUPER.neo-miR-345 group was significantly higher than that in MHCC97-L pSUPER.neo group (P<0.05). There was a significant difference in terms of HbsAg expression between the MHCC97-L pSUPER.neo-miR-101 and MHCC97-L pSUPER.neo-miR-345 groups (P<0.05). The proliferation of BEL-7404 cells in the BEL-7404 pSUPER.neo-miR-101 group was significantly lower than that in the BEL-7404 pSUPER.neo group (P<0.05). The proliferation of BEL-7404 cells in the BEL-7404 pSUPER.neo-miR-345 group was significantly higher than that in the BEL-7404 pSUPER.neo group (P<0.05). The proliferation of BEL-7404 cells in BEL-7404 pSUPER.neo-miR-101 group was different from that in BEL-7404 pSUPER.neo-miR-345 group (P<0.05). miR-101 reduced the level of HBV replication, and inhibited the proliferation of liver cancer cells. miR-345 also upregulated the level of HBV replication, and promoted the proliferation of liver cancer cells.

The relationship between microRNAs and Rab family GTPases in human cancers

microRNAs (miRNAs), as a group of noncoding RNAs, posttranscriptionally control gene expression by binding to 3'-untranslated region (3'-UTR). Ras-associated binding (Rab) proteins function as molecular switches for regulating vesicular transport, which mainly have oncogenic roles in cancer development and preventing the efficacy of chemotherapies. Increased evidence supported that miRNAs/Rabs interaction have been determined as potential therapeutics for cancer therapy. Nevertheless, instability and cross-targeting of miRNAs are main limitations of using miRNA-based therapeutic. The mutual interplay between Rabs and miRNAs has been poorly understood. In the present review, we focused on the essence and activity of these molecules in cancer pathogenesis. Also, numerous hindrances and potential methods in the expansion of miRNA as an anticancer therapeutics are mentioned.

MicroRNA-101 inhibits cell migration and invasion in bladder cancer via targeting FZD4

Dysfunction of microRNAs (miRs) has been implicated in the development and progression of various human cancers. Our previous study demonstrated that miR-101 inhibited bladder cancer cell proliferation and invasion through inhibition of c-FOS expression. As an miR generally has many targets, other targets of miR-101 may also serve important roles in bladder cancer progression. Reverse transcription-quantitative polymerase chain reaction and western blot analyses were used to examine mRNA and protein expression, respectively. Wound healing and Transwell assays were conducted to study cell migration and invasion, respectively. The luciferase reporter gene assay was performed to verify one of the targets of miR-101. The data in the present study indicate that the expression of miR-101 is significantly reduced in bladder cancer tissues compared with that in adjacent non-tumour tissues. In addition, miR-101 expression is also downregulated in bladder cancer cell lines compared with that in normal bladder epithelial cells. Furthermore, low expression of miR-101 was significantly associated with tumour metastasis, advanced clinical stage, and poor prognosis in bladder cancer. Frizzled class receptor 4 (FZD4) was identified as a novel target of miR-101 in bladder cancer cells. The expression of FZD4 was significantly upregulated in bladder cancer tissues and cell lines. Both miR-101 overexpression and FZD4 inhibition caused a significant reduction of the migration and invasion of bladder cancer cells, whereas overexpression of FZD4 reversed the suppressive effects of miR-101 on bladder cancer cell migration and invasion. In conclusion, it was demonstrated that miR-101 downregulation is associated with bladder cancer progression and that miR-101 can inhibit bladder cancer cell migration and invasion via directly targeting FZD4. The present study expands the understanding of the molecular mechanisms underlying bladder cancer progression.

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.

LINC00052/miR-101-3p axis inhibits cell proliferation and metastasis by targeting SOX9 in hepatocellular carcinoma

Long non-coding RNAs (lncRNAs) have emerged as critical regulators in a variety of diseases, including many tumors, such as hepatocellular carcinoma (HCC). However, the function and mechanisms responsible for these molecules in HCC are not thoroughly understood. In our previous study, we found that LINC00052 was acted as a tumor suppressor in HCC. In this study, we performed transcription microarray analysis to investigate the target gene of LINC00052, and found that knockdown of LINC00052 significantly increased the expression of SRY-related HMG-box gene 9 (SOX9), which plays an oncogenic role in HCC. Moreover, luciferase reporter assay revealed that LINC00052 promoted miR-101-3p expression by enhancing its promoter activity. In addition, online database analysis tools and luciferase assays showed that miR-101-3p could target SOX9. Quantitative real-time polymerase chain reaction (qRT-PCR) demonstrated that miR-101-3p was downregulated in HCC tissues and HCC cell lines. And we found a positive relationship between LINC00052 and miR-101-3p, and a negative relationship between miR-101-3p and SOX9 in HCC tissues. Besides, miR-101-3p was involved in LINC00052 inhibits HCC cells proliferation and metastasis. At the molecular level, LINC00052 downgulated SOX9 to inhibit HCC cells proliferation and metastasis by interacting with miR-101-3p. It might be a potential application for HCC therapy.

Dysregulation of cellular microRNAs by human oncogenic viruses - Implications for tumorigenesis

Infection with certain animal and human viruses, often referred to as tumor viruses, induces oncogenic processes in their host. These viruses can induce tumorigenesis through direct and/or indirect mechanisms, and the regulation of microRNAs expression has been shown to play a key role in this process. Some human oncogenic viruses can express their own microRNAs; however, they all can dysregulate the expression of cellular microRNAs, facilitating their respective life cycles. The modulation of cellular microRNAs expression brings consequences to the host cells that may lead to malignant transformation, since microRNAs regulate the expression of genes involved in oncogenic pathways. This review focus on the mechanisms used by each human oncogenic virus to dysregulate the expression of cellular microRNAs, and their impact on tumorigenesis.

MicroRNA-26b-5p regulates cell proliferation, invasion and metastasis in human intrahepatic cholangiocarcinoma by targeting S100A7

The present study aimed to investigate the effects of microRNA expression in intrahepatic cholangiocarcinoma (ICC). It was identified that the expression of microRNA-26b-5p (miR-26b-5p) was downregulated in ICC tissues compared with matched adjacent non-tumor tissues. Furthermore, miR-26b-5p expression was downregulated in metastatic ICC tumor tissues and invasive ICC cell line subpopulations compared with non-metastatic tumor tissue and the parental ICC cells. In vitro studies demonstrated that transfection with an miR-26b-5p mimic inhibited the proliferation, migration and invasion of RBE and HCCC-9810 cells, whereas an miR-26b-5p inhibitor promoted these abilities. S100 calcium-binding protein A7 (S100A7) was predicted as a direct target of miR-26b-5p. Transfection with an miR-26b-5p mimic decreased S100A7 expression, whereas an miR-26b-5p inhibitor increased S100A7 expression. The result of a dual luciferase reporter assay also indicated this interaction. S100A7 was therefore confirmed as a direct target of miR-26b-5p in ICC. The knockdown of S100A7 abrogated the effect of miR-26b-5p on cell migration in RBE and HCCC-9810 cells. In conclusion, the present study demonstrated that miR-26b-5p suppresses the proliferation, migration and invasion of ICC cells by suppressing S100A7.

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.

MicroRNAs and cancer: Key paradigms in molecular therapy

MicroRNAs (miRNAs) are a type of small non-coding RNA molecule that performs an important role in post-transcriptional gene regulation. Since miRNAs were first identified in 1993, a number of studies have demonstrated that they act as tumor suppressors or oncogenes in human cancer, including colorectal, lung, brain, breast and liver cancer, and leukemia. Large high-throughput studies have previously revealed that miRNA profiling is critical for the diagnosis and prognosis of patients with cancer, while certain miRNAs possess the potential to be used as diagnostic and prognostic biomarkers or therapeutic targets in cancer. The present study reviews the studies and examines the roles of miRNAs in cancer diagnosis, prognosis and treatment, and discusses the potential therapeutic modality of exploiting miRNAs.

CMIP is oncogenic in human gastric cancer cells

Gastric cancer is one of the most common cancers and the second leading cause of cancer-associated mortality worldwide. Recurrence, metastasis and resistance to drug treatment are the main barrier to survival of patients with advanced stage gastric cancer. Further study of the molecular mechanisms involved will improve the therapeutic options for gastric cancer. In a previous study, c-Maf was discovered as an oncogene transduced in the avian AS42 retrovirus, and was found to be overexpressed in multiple myeloma and angioimmunoblastic T-cell lymphoma. c-Maf inducing protein (CMIP) is involved in the c-Maf signaling pathway, which was reported to serve an important role in human minimal change nephrotic syndrome and in human reading and language related behavior. However, the relationship between CMIP and human gastric cancer has not yet been reported. In the present study, CMIP protein levels in gastric cancer tissues and cells were measured using immunohistochemistry and western blot analysis; the expression of CMIP protein was significantly higher in gastric cancer tissues compared with normal gastric tissues. Expression was positively associated with poorer clinical parameters, relapse-free survival and overall survival. Furthermore, using cell counting, Cell Counting Kit-8, colony formation, wound healing and Transwell assays, together with flow cytometry, CMIP depletion by RNA interference was observed to reduce the capacity of gastric cancer cells to proliferate and migrate in vitro. Furthermore, the upstream and downstream genes of CMIP were analyzed by luciferase reporter assay and reverse transcription quantitative polymerase chain reaction, which indicated that CMIP was a direct target of miR-101-3p. In addition, CMIP knockdown was observed to result in the downregulation of MDM2 and mitogen activated protein kinase (MAPK) expression at the mRNA level. In conclusion, CMIP demonstrated an oncogenic role in human gastric cancer cells. Furthermore, microRNA-101-3p, MDM2 and MAPK were involved in the CMIP signaling pathway in gastric cancer. CMIP could be a novel target for further investigation in the clinical therapeutic management of gastric cancer.

1,25D3 differentially suppresses bladder cancer cell migration and invasion through the induction of miR-101-3p

Metastasis is the major cause of bladder cancer death. 1,25D3, the active metabolite of vitamin D, has shown anti-metastasis activity in several cancer model systems. However, the role of 1,25D3 in migration and invasion in bladder cancer is unknown. To investigate whether 1,25D3 affects migration and invasion, four human bladder cell lines with different reported invasiveness were selected: low-invasive T24 and 253J cells and highly invasive 253J-BV and TCCSUP cells. All of the four bladder cancer cells express endogenous and inducible vitamin D receptor (VDR) as examined by immunoblot analysis. 1,25D3 had no effect on the proliferation of bladder cancer cells as assessed by MTT assay. In contrast, 1,25D3 suppressed migration and invasion in the more invasive 253J-BV and TCCSUP cells, but not in the low-invasive 253J and T24 cells using "wound" healing, chemotactic migration and Matrigel-based invasion assays. 1,25D3 promoted the expression of miR-101-3p and miR-126-3p in 253J-BV cells as examined by qRT-PCR. miR-101-3p inhibitor partially abrogated and pre-miR-101-3p further suppressed the inhibition of 1,25D3 on migration and invasion in 253J-BV cells. Further, 1,25D3 enhanced VDR recruitment to the promoter region of miR-101-3p using ChIP-qPCR assay. 1,25D3 enhanced the promoter activity of miR-101-3p as evaluated by luciferase reporter assay. Taken together, 1,25D3 suppresses bladder cancer cell migration and invasion in two invasive/migration competent lines but not in two less invasive/motile lines, which is partially through the induction of miR-101-3p expression at the transcriptional level.

Association of RAB5 overexpression in pancreatic cancer with cancer progression and poor prognosis via E-cadherin suppression

Pancreatic cancer is a common type of cancer with poor prognosis worldwide. Postoperative survival depends on the existence of metastasis. Elucidation of the mechanism underlying cancer progression is important to improve prognosis. The RAS-associated protein RAB5 activates intracellular membrane trafficking, and RAB5 expression is correlated to progression and epithelial mesenchymal transition in various cancers.

The expression of RAB5 and E-cadherin in 111 pancreatic cancer samples was investigated by immunohistochemical staining, and the relationship among RAB5 expression, clinicopathological factors, and E-cadherin expression was assessed. Furthermore, RAB5 suppression analysis by siRNA was performed to determine the roles of RAB5 in morphological change, proliferation potency, cell migration ability, and invasiveness of the pancreatic cancer cell line.

High RAB5 expression correlated with the presence of lymphatic invasion and venous invasion and low E-cadherin expression. Patients with high RAB5 expression had a poorer prognosis than those with low RAB5 expression. RAB5 suppression in pancreatic cancer cells enhanced E-cadherin expression; changed cell morphology from spindle to round; and inhibited proliferation, invasion, and cell migration.

RAB5 contributes to poor prognosis and progression in pancreatic cancer patients. It may be a promising candidate for individualized therapy in refractory pancreatic cancer.

MiR-101-3p Regulates the Viability of Lung Squamous Carcinoma Cells via Targeting EZH2

The aim of this study was to investigate the effects of miR-101-3p on the viability, migration, invasion, and mitosis of lung squamous carcinoma cells by inhibiting EZH2. In this study, RT-qPCR was used to detect the expression of miR-101-3p and EZH2 in both tissues and cells at RNA level. The dual luciferase reporter gene system was used to determine whether there was targeting relationship between miR-101-3p and EZH2-3'UTR. Western Blot was used to detect the expression of EZH2 as well as the proliferation and invasion related proteins. The CCK-8 assay, Transwell invasion assay, wound healing assay and flow cytometry were conducted to test the cell viability, invasion, migration and apoptosis. The results of RT-qPCR and Western blot showed that miR-101-3p was low-expressed and EZH2 was overexpressed in lung squamous cell carcinoma tissues and cells. Meanwhile the Western blot confirmed the effects of EZH2 expression on the proliferation and invasion of carcinoma cells. The results of luciferase assay and RT-qPCR showed that miR-101-3p had a negative regulation effect on EZH2. The CCK-8 assay, Transwell invasion assay, wound healing assay and flow cytometry results showed that the inhibition of EZH2 or the up-regulation of miR-101-3p inhibited the viability, migration, invasion and cell cycle but promoted cell apoptosis of lung squamous cell carcinoma. MiR-101-3p could inhibit the viability, migration, invasion, and cell cycle of lung squamous carcinoma cells by inhibiting the EZH2. J. Cell. Biochem. 118: 3142-3149, 2017. © 2016 Wiley Periodicals, Inc.

Clinical Value of miR-101-3p and Biological Analysis of its Prospective Targets in Breast Cancer: A Study Based on The Cancer Genome Atlas (TCGA) and Bioinformatics

Background

MiR-101-3p can promote apoptosis and inhibit proliferation, invasion, and metastasis in breast cancer (BC) cells. However, its mechanisms in BC are not fully understood. Therefore, a comprehensive analysis of the target genes, pathways, and networks of miR-101-3p in BC is necessary.

Material/Methods

The miR-101 profiles for 781 patients with BC from The Cancer Genome Atlas (TCGA) were analyzed. Gene expression profiling of GSE31397 with miR-101-3p transfected MCF-7 cells and scramble control cells was downloaded from Gene Expression Omnibus (GEO), and the differentially expressed genes (DEGs) were identified. The potential genes targeted by miR-101-3p were also predicted. Gene Ontology (GO) and pathway and network analyses were constructed for the DEGs and predicted genes.

Results

In the TCGA data, a low level of miR-101-2 expression might represent a diagnostic (AUC: 0.63) marker, and the miR-101-1 was a prognostic (HR=1.79) marker. MiR-101-1 was linked to the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), and miR-101-2 was associated with the tumor (T), lymph node (N), and metastasis (M) stages of BC. Moreover, 427 genes were selected from the 921 DEGs in GEO and the 7924 potential target genes from the prediction databases. These genes were related to transcription, metabolism, biosynthesis, and proliferation. The results were also significantly enriched in the VEGF, mTOR, focal adhesion, Wnt, and chemokine signaling pathways.

Conclusions

MiR-101-1 and miR-101-2 may be prospective biomarkers for the prognosis and diagnosis of BC, respectively, and are associated with diverse clinical parameters. The target genes of miR-101-3p regulate the development and progression of BC. These results provide insight into the pathogenic mechanism and potential therapies for BC.

Targeting Rabs as a novel therapeutic strategy for cancer therapy

Rab GTPases constitute the largest family of small GTPases. Rabs regulate not only membrane trafficking but also cell signaling, growth and survival, and development. Increasingly, Rabs and their effectors are shown to be overexpressed or subject to loss-of-function mutations in a variety of disease settings, including cancer progression. This review provides an overview of dysregulated Rab proteins in cancer, and highlights the signaling and secretory pathways in which they operate, with the aim of identifying potential avenues for therapeutic intervention. Recent progress and perspectives for direct and/or indirect targeting of Rabs are also summarized.

miR-101-3p Suppresses HOX Transcript Antisense RNA (HOTAIR)-Induced Proliferation and Invasion Through Directly Targeting SRF in Gastric Carcinoma Cells

miR-101-3p has been identified as a tumor suppressor in several cancers, but its exact role in gastric adenocarcinoma is still largely unknown. In this study, we found that, compared with the RGM-1 human normal gastric epithelial cells, miR-101-3p was significantly downregulated in all six human gastric adenocarcinoma cell lines, including BGC-823, MNK-45, MGC-803, SGC-7901, AGS, and HGC-27. Overexpression of miR-101-3p suppressed both the proliferation and invasion of AGS gastric adenocarcinoma cells, and knockdown of miR-101-3p displayed the opposite effect. In addition, miR-101-3p could directly target and suppress the expression of the serum response factor (SRF) gene, which is a transcription factor of HOTAIR, a well-characterized tumor promoter lncRNA. miR-101-3p negatively regulated SRF-mediated transcription of HOTAIR. Moreover, silencing of either SRF or HOTAIR could counteract the promotion of gastric adenocarcinoma cell proliferation and invasion by miR-101-3p inhibition. Our findings indicate that miR-101-3p suppresses HOTAIR-induced proliferation and invasion through directly targeting SRF in gastric carcinoma cells.

MiR-101 and doxorubicin codelivered by liposomes suppressing malignant properties of hepatocellular carcinoma

MiR-101, an important tumor-suppressive microRNA (miRNA) in hepatocellular carcinoma (HCC), has been affirmed significantly downregulated in HCC and participated in promoting apoptosis, decreasing proliferation and invasiveness of HCC cells, as well as increasing sensitivity of chemotherapeutic drug. However, miR-101-based combination therapies with doxorubicin (DOX) are not reported yet. Recently, nanomaterials-based approaches, especially liposome formulations, have been approved for clinical use and seem to provide a great opportunity to codeliver therapeutic agents for cancer therapy. In this study, we have successfully prepared liposome (L) nanoparticles to efficiently deliver miR-101 and DOX to HCC cells simultaneously. The effects of codelivery system miR-101/doxorubicin liposome (miR-101/DOX-L) on tumor malignant phenotypes of HCC cells were evaluated through analyzing cell proliferation, colony formation, cell migration, cell invasion, cell apoptosis assay, and the expression of related genes. In subcutaneous xenografts developed by HCC cells, the inhibition of tumor growth was analyzed through gross morphology, growth curve, proliferation marker Ki-67, apoptosis signals, and the expression of related genes. These experiments demonstrated that miR-101/DOX-L inhibited tumor properties of liver cancer cells in vitro and in vivo through targeting correlative genes by combinatory role of miR-101 and DOX. In conclusion, our results indicated that liposome nanoparticle is a reliable delivery strategy to codeliver miR-101 and DOX simultaneously, and miR-101- and DOX-based combination therapy can result in significant synergetic antitumor effects in vivo and vitro.

Differentially Expressed Long Non-Coding RNAs Were Predicted to Be Involved in the Control of Signaling Pathways in Pediatric Astrocytoma

Expression changes for long non-coding RNAs (lncRNAs) have been identified in adult glioblastoma multiforme (GBM) and in a mixture of adult and pediatric astrocytoma. Since adult and pediatric astrocytomas are molecularly different, the mixture of both could mask specific features in each. We determined the global expression patterns of lncRNAs and messenger RNA (mRNAs) in pediatric astrocytoma of different histological grades. Transcript expression changes were determined with an HTA 2.0 array. lncRNA interactions with microRNAs and mRNAs were predicted by using an algorithm and the LncTar tool, respectively. Interactomes were constructed with the HIPPIE database and visualized with the Cytoscape platform. The array showed expression changes in 156 and 207 lncRNAs in tumors (versus the control) and in pediatric GBM (versus low-grade astrocytoma), respectively. Predictions identified lncRNAs that have putative microRNA binding sites, which might suggest that they function as sponges in these tumors. Also, lncRNAs were shown to interact with many mRNAs, such as Pleckstrin homology-like domain, family A, member 1 (PHLDA1) and sulfatase 2 (SULF2). For example, qPCR found long intergenic non-coding RNA regulator of reprogramming (linc-RoR) expression levels upregulated in pediatric GBM when they were compared with control tissues or with low-grade tumors. Meanwhile, PHLDA1 and ELAV-like RNA binding protein 1 (ELAV1) showed expression changes in tumors relative to the control. Our data showed many lncRNAs with expression changes in pediatric astrocytoma, which might be involved in the regulation of different signaling pathways.

HBV preS2 promotes the expression of TAZ via miRNA-338-3p to enhance the tumorigenesis of hepatocellular carcinoma

Transactivators encoded by HBV, including HBx and preS2, play critical role in hepatocellular carcinoma (HCC). YAP, a downstream effector of the Hippo pathway, is involved in hepatocarcinogenesis mediated by HBx. Here, we investigated whether preS2, another transactivator encoded by HBV, regulates the Hippo pathway to promote HCC. We found that preS2 overexpression upregulated TAZ, a downstream effector of the Hippo pathway, at protein level but not at mRNA level. preS2 suppressed miRNA-338-3p expression in HCC cell lines. miRNA-338-3p mimics downregulated TAZ, while miRNA-338-3p inhibitor restored the expression of TAZ, suggesting that TAZ is a direct target of miRNA-338-3p. TAZ overexpression stimulated growth of HCC cell lines. Knockdown of TAZ dampened preS2-promoted HCC proliferation and migration. Thus, preS2 upregulates TAZ expression by repressing miRNA-338-3p. TAZ is necessary for preS2-promoted HCC proliferation and migration

miR-101 inhibits glioma cell invasion via the downregulation of COX-2

Glioma is the most common type of primary tumor of the central nervous system. The present study aimed to demonstrate the role of miR-101 and cyclooxygenase-2 (COX-2) in the initiation and development of glioma. The expression of miR-101 and COX-2 in normal and malignant human glial cells and tissues was determined by western blotting and quantitative polymerase chain reaction analysis. The role of miR-101 on COX-2 expression was evaluated by a dual-luciferase reporter assay. The effects of miR-101 and COX-2 in glioma cell proliferation and invasion was verified by CCK-8 test and Transwell assays, respectively. The present study demonstrated that miR-101 expression was downregulated while COX-2 was upregulated in glioma tissues and cells. Furthermore, transfection of miR-101 significantly downregulated COX-2 expression in both U373 and U87 glioma cells. In addition, further experiments revealed that overexpression of miR-101 resulted in significant inhibition of the in vitro proliferation and migration of glioma cells, and the in vivo growth of established tumors. Direct downregulation of COX-2 by transfection with corresponding small interfering RNA also inhibited the proliferation and invasion of glioma cells. These results indicate that downregulation of miR-101 is involved in the initiation and development of glioma via COX-2 upregulation.

Dysregulated miRNA in progression of hepatocellular carcinoma: A systematic review

Hepatocellular carcinoma (HCC) is the fifth most frequent cancer and the third cause of cancer-related mortality worldwide. The primary risk factor for HCC is liver cirrhosis secondary to persistent infection with hepatitis B virus or hepatitis C virus. Although a number of cellular phenomena and molecular events have been reported to facilitate tumor initiation, progression and metastasis, the exact etiology of HCC has not yet been fully uncovered. miRNA, a class of non-coding RNA, negatively regulate post-transcriptional processes that participate in crucial biological processes, including development, differentiation, apoptosis and proliferation. In the liver, specific miRNA can be negative regulators of gene expression. Recent studies have uncovered the contribution of miRNA to cancer pathogenesis as they can function as oncogenes or tumor suppressor genes. In addition, other studies have demonstrated their potential value in the clinical management of patients with HCC as some miRNA may be used as prognostic or diagnostic markers. In this review, we summarize the current knowledge about the roles of miRNA in the carcinogenesis and progression of HCC.

Wnt-5a-regulated miR-101b controls COX2 expression in hippocampal neurons

Background

Wnt-5a is a member of the WNT family of secreted lipoglycoproteins, whose expression increases during development; moreover, Wnt-5a plays a key role in synaptic structure and function in the adult nervous system. However, the mechanism underlying these effects is still elusive. MicroRNAs (miRNAs) are a family of small non-coding RNAs that control the gene expression of their targets through hybridization with complementary sequences in the 3′ UTR, thereby inhibiting the translation of the target proteins. Several evidences indicate that the miRNAs are actively involved in the regulation of neuronal function.

Results

In the present study, we examined whether Wnt-5a modulates the levels of miRNAs in hippocampal neurons. Using PCR arrays, we identified a set of miRNAs that respond to Wnt-5a treatment. One of the most affected miRNAs was miR-101b, which targets cyclooxygenase-2 (COX2), an inducible enzyme that converts arachidonic acid to prostanoids, and has been involved in the injury/inflammatory response, and more recently in neuronal plasticity. Consistent with the Wnt-5a regulation of miR-101b, this Wnt ligand regulates COX2 expression in a time-dependent manner in cultured hippocampal neurons.

Conclusion

The biological processes induced by Wnt-5a in hippocampal neurons, involve the regulation of several miRNAs including miR-101b, which has the capacity to regulate several targets, including COX-2 in the central nervous system.

Early and late effects of prenatal corticosteroid treatment on the microRNA profiles of lung tissue in rats

Glucocorticoids have been administered to mothers at risk of premature delivery to induce maturation of preterm fetal lungs and prevent the development of respiratory distress syndrome. Micro (mi)RNAs serve various crucial functions in cell proliferation, differentiation and organ development; however, few studies have demonstrated an association between miRNAs and lung development. The aim of the present study was to investigate alterations in the miRNA profiles of rat lung tissue following prenatal glucocorticoid therapy for fetal lung development. The differences in miRNA expression profiles were compared between postnatal days 7 (D7) and 120 (D120) rat lung tissues, followed by validation using reverse transcription-quantitative polymerase chain reaction. The miRNA profiles of rat lung tissues following prenatal dexamethasone (DEX) therapy were also investigated. miRNAs with 2-fold changes were selected for further analysis. At D120, 6 upregulated and 6 downregulated miRNAs were detected, compared with D7. Among these differentially expressed miRNAs, miR-101-3p and miR-99b-5p were associated with the lowest and highest expressions of miRNA at D7, respectively. A limited impact on the miRNA profiles of rat lung tissues was observed following prenatal DEX treatment, which may help to further clarify the mechanisms underlying normal lung development. However, the results of the present study cannot entirely elucidate the effects of prenatal DEX treatment on the lung development of premature infants, and further studies investigating the impact of prenatal corticosteroids on fetal lung miRNA profiles are required.

Role of microRNAs in inflammation-associated liver cancer

Liver cancer, primarily hepatocellular carcinoma (HCC), is a major cause of cancer-related death worldwide. HCC is a suitable model of inflammation-induced cancer because more than 90% of HCC cases are caused by liver damage and chronic inflammation. Several inflammatory response pathways, such as NF-κB and JAK/STAT3 signaling pathways, play roles in the crosstalk between inflammation and HCC. MicroRNAs (miRNAs) are evolutionarily conserved, short endogenous, non-coding single-stranded RNAs that are involved in various biological and pathological processes by regulating gene expression and protein translation. Evidence showed that miRNAs play a pivotal role in hepatitis virus infection and serve as promoters or inhibitors of inflammatory response. Aberrant miRNA was observed during liver inflammation and HCC. Many dysregulated miRNAs modulate the initiation and progression of inflammation-induced HCC. This review summarizes the role and functions of miRNAs in inflammation-associated HCC, as well as the designed therapeutics targeting miRNAs to treat liver inflammation and HCC.

MicroRNA-101 suppresses migration and invasion via targeting vascular endothelial growth factor-C in hepatocellular carcinoma cells

MicroRNAs (miRNAs) are a class of non-coding RNAs 18-25 nucleotides in length, which play important roles in the regulation of cancer progression through gene silencing. miRNA (miR)-101 has been suggested to be associated with hepatocellular carcinoma (HCC). However, the detailed role of miR-101 in HCC metastasis and the underlying mechanism remain largely unclear. The present study demonstrated that the expression of miR-101 was significantly reduced in HCC tissues compared with that in matched normal adjacent tissues. miR-101 was also found to be downregulated in four HCC cell lines compared with its expression in a normal liver cell line. Vascular endothelial growth factor (VEGF)-C was further identified as a direct target of miR-101, and the protein expression of VEGF-C was downregulated by miR-101 in HepG2 HCC cells. Furthermore, the overexpression of miR-101 and the knockdown of VEGF-C significantly inhibited HepG2 cell migration and invasion, while restoration of VEGF-C reversed the inhibitory effect of miR-101 overexpression on HepG2 cell migration and invasion. Finally, the expression of VEGF-C was notably increased in HCC tissues and cell lines. These findings suggest that miR-101 exerts a suppressive effect on HCC cell migration and invasion, at least in part through the direct inhibition of VEGF-C protein expression. Therefore, the miR-101/VEGF-C axis may serve as a potential therapeutic target for HCC metastasis.

The role of endocytic Rab GTPases in regulation of growth factor signaling and the migration and invasion of tumor cells

Metastasis is characterized pathologically by uncontrolled cell invasion, proliferation, migration and angiogenesis. It is a multistep process that encompasses the modulation of membrane permeability and invasion, cell spreading, cell migration and proliferation of the extracellular matrix, increase in cell adhesion molecules and interaction, decrease in cell attachment and induced survival signals and propagation of nutrient supplies (blood vessels). In cancer, a solid tumor cannot expand and spread without a series of synchronized events. Changes in cell adhesion receptor molecules (e.g., integrins, cadherin-catenins) and protease expressions have been linked to tumor invasion and metastasis. It has also been determined that ligand-growth factor receptor interactions have been associated with cancer development and metastasis via the endocytic pathway. Specifically, growth factors, which include IGF-1 and IGF-2 therapy, have been associated with most if not all of the features of metastasis. In this review, we will revisit some of the key findings on perhaps one of the most important hallmarks of cancer metastasis: cell migration and cell invasion and the role of the endocytic pathway in mediating this phenomenon.

MicroRNA-101 is repressed by EZH2 and its restoration inhibits tumorigenic features in embryonal rhabdomyosarcoma

Background

Rhabdomyosarcoma (RMS) is a pediatric soft tissue sarcoma arising from myogenic precursors that have lost their capability to differentiate into skeletal muscle. The polycomb-group protein EZH2 is a Lys27 histone H3 methyltransferase that regulates the balance between cell proliferation and differentiation by epigenetically silencing muscle-specific genes. EZH2 is often over-expressed in several human cancers acting as an oncogene. We previously reported that EZH2 inhibition induces cell cycle arrest followed by myogenic differentiation of RMS cells of the embryonal subtype (eRMS). MiR-101 is a microRNA involved in a negative feedback circuit with EZH2 in different normal and tumor tissues. To that, miR-101 can behave as a tumor suppressor in several cancers by repressing EZH2 expression. We, therefore, evaluated whether miR-101 is de-regulated in eRMS and investigated its interplaying with EZH2 as well as its role in the in vitro tumorigenic potential of these tumor cells.

Results

Herein, we report that miR-101 is down-regulated in eRMS patients and in tumor cell lines compared to their controls showing an inverse pattern of expression with EZH2. We also show that miR-101 is up-regulated in eRMS cells following both genetic and pharmacological inhibition of EZH2. In turn, miR-101 forced expression reduces EZH2 levels as well as restrains the migratory potential of eRMS cells and impairs their clonogenic and anchorage-independent growth capabilities. Finally, EZH2 recruitment to regulatory region of miR-101-2 gene decreases in EZH2-silenced eRMS cells. This phenomenon is associated to reduced H3K27me3 levels at the same regulatory locus, indicating that EZH2 directly targets miR-101 for repression in eRMS cells.

Conclusions

Altogether, our data show that, in human eRMS, miR-101 is involved in a negative feedback loop with EZH2, whose targeting has been previously shown to halt eRMS tumorigenicity. They also demonstrate that the re-induction of miR-101 hampers the tumor features of eRMS cells. In this scenario, epigenetic dysregulations confirm their crucial role in the pathogenesis of this soft tissue sarcoma.

Electronic supplementary material

The online version of this article (doi:10.1186/s13148-015-0107-z) contains supplementary material, which is available to authorized users.

MiR-141 targets ZEB2 to suppress HCC progression

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related deaths worldwide. Increasing evidence suggests that microRNAs (miRNAs) are associated with HCC tumorigenesis. The present study was designed to define the role of miR-141 in HCC. The expression of miR-141 was significantly decreased in four HCC cell lines. Overexpression of miR-141 suppressed both the growth and the motility of HCC cells. Furthermore, we identified zinc finger E-box binding homeobox 2 (ZEB2) as a target of miR-141 and miR-141 functioned as a tumor suppressor via ZEB2 targeting in HCC. These data provide a novel potential therapeutic target for HCC treatment.