MicroRNA miR-204 and miR-1236 inhibit hepatitis B virus replication via two different mechanisms

Potential diagnostic value of miRNAs in sexually transmitted infections

MiRNAs are small endogenous non-coding RNAs that have been demonstrated to be involved in post-transcriptional gene silencing, regulating a number of metabolic functions in the human body, including immune response, cellular physiology, organ development, angiogenesis, signaling, and other aspects. As popular molecules that have been studied in previous years, given their extensive regulatory functions, miRNAs hold considerable promise as non-invasive biomarkers. Sexually transmitted infections(STIs) are still widespread and have an adverse effect on individuals, communities, and society worldwide. miRNAs in the regulatory networks are generally involved in their molecular processes of formation and development. In this review, we discuss the value of miRNAs for the diagnosis of STIs.

Hepatitis B Virus Modulated Transcriptional Regulatory Map of Hepatic Cellular MicroRNAs

Hepatitis B virus (HBV) is an enveloped, hepatotropic, noncytopathic virus with a partially double-stranded DNA genome. It infects hepatocytes and is associated with progression to liver fibrosis and cirrhosis, culminating in hepatocellular carcinoma (HCC), accounting for 55% of total HCC cases. MicroRNAs (miRNAs) regulated by HBV play an important role in these pathologies. Mapping the miRNAs responsive to HBV and HBV-specific proteins, including HBV X protein (HBx) that harbor the majority of HBV-human protein interactions, could aid accelerate the diagnostics and therapeutics innovation against the infection and associated diseases. With this in mind, we used a unique annotation strategy whereby we first amassed 362 mature HBV responsive-human Differentially Expressed miRNAs (HBV-hDEmiRs). The core experimentally-validated messenger RNA targets of the HBV-hDEmiRs were mostly associated with viral infections and hepatic inflammation processes. Moreover, our annotation strategy enabled the characterization of HBx-dependent/independent HBV-hDEmiRs as a tool for evaluation of the impact of HBx as a therapeutic target. Bioinformatics analysis of the HBV-human protein-protein interactome revealed new insights into the transcriptional regulatory network of the HBV-hDEmiRs. We performed a comparative analysis of data on miRNAs gathered from HBV infected cell line studies and from tissue studies of fibrosis, cirrhosis, and HCC. Accordingly, we propose hsa-miR-15a-5p that is downregulated by multiple HBV proteins, including HBx, as a potential biomarker of HBV infection, and its progression to HCC. In all, this study underscores (1) the complexity of miRNA regulation in response to HBV infection and its progression into other liver pathologies and (2) provides a regulatory map of HBV-hDEmiRs and the underlying mechanisms modulating their expression through a cross talk between HBV viral proteins and human transcription factors.

The Circulating miRNA Profile of Chronic Hepatitis D and B Patients Is Comparable but Differs from That of Individuals with HBeAg-Negative HBV Infection

miRNAs circulating in whole serum and HBsAg-particles are differentially expressed in chronic hepatitis B (CHB) and HBeAg-negative-HBV infection (ENI); their profiles are unknown in chronic hepatitis D (CHD). Serum- and HBsAg-associated miRNAs were analyzed in 75 subjects of 3 well-characterized groups (CHB 25, CHD 25, ENI 25) using next-generation sequencing (NGS). Overall miRNA profiles were consonant in serum and HBsAg-particles but significantly different according to the presence of hepatitis independently of Hepatitis D Virus (HDV)-co-infection. Stringent (Bonferroni Correction < 0.001) differential expression analysis showed 39 miRNAs upregulated in CHB vs. ENI and 31 of them also in CHD vs. ENI. miRNA profiles were coincident in CHB and CHD with only miR-200a-3p upregulated in CHB. Three miRNAs (miR-625-3p, miR-142-5p, and miR-223-3p) involved in immune response were upregulated in ENI. All 3 hepatocellular miRNAs of MiR-B-Index (miR-122-5p, miR-99a-5p, miR-192-5p) were overexpressed in both CHB and CHD patients. In conclusion, CHD and CHB patients showed highly similar serum miRNA profiling that was significantly different from that of individuals with HBeAg-negative infection and without liver disease.

Dysregulated microRNAs as a biomarker for diagnosis and prognosis of hepatitis B virus-associated hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a malignancy with a high incidence and fatality rate worldwide. Hepatitis B virus (HBV) infection is one of the most important risk factors for its occurrence and development. Early detection of HBV-associated HCC (HBV-HCC) can improve clinical decision-making and patient outcomes. Biomarkers are extremely helpful, not only for early diagnosis, but also for the development of therapeutics. MicroRNAs (miRNAs), a subset of non-coding RNAs approximately 22 nucleotides in length, have increasingly attracted scientists' attention due to their potential utility as biomarkers for cancer detection and therapy. HBV profoundly impacts the expression of miRNAs potentially involved in the development of hepatocarcinogenesis. In this review, we summarize the current progress on the role of miRNAs in the diagnosis and treatment of HBV-HCC. From a molecular standpoint, we discuss the mechanism by which HBV regulates miRNAs and investigate the exact effect of miRNAs on the promotion of HCC. In the near future, miRNA-based diagnostic, prognostic, and therapeutic applications will make their way into the clinical routine.

MicroRNAs: Small molecules with big impacts in liver injury

A type of small noncoding RNAs known as microRNAs (miRNAs) fine-tune gene expression posttranscriptionally by binding to certain messenger RNA targets. Numerous physiological processes in the liver, such as differentiation, proliferation, and apoptosis, are regulated by miRNAs. Additionally, there is growing evidence that miRNAs contribute to liver pathology. Extracellular vesicles like exosomes, which contain secreted miRNAs, may facilitate paracrine and endocrine communication between various tissues by changing the gene expression and function of distal cells. The use of stable miRNAs as noninvasive biomarkers was made possible by the discovery of these molecules in body fluids. Circulating miRNAs reflect the conditions of the liver that are abnormal and may serve as new biomarkers for the early detection, prognosis, and evaluation of liver pathological states. miRNAs are appealing therapeutic targets for a range of liver disease states because altered miRNA expression is associated with deregulation of the liver's metabolism, liver damage, liver fibrosis, and tumor formation. This review provides a comprehensive review and update on miRNAs biogenesis pathways and mechanisms of miRNA-mediated gene silencing. It also outlines how miRNAs affect hepatic cell proliferation, death, and regeneration as well as hepatic detoxification. Additionally, it highlights the diverse functions that miRNAs play in the onset and progression of various liver diseases, including nonalcoholic fatty liver disease, alcoholic liver disease, fibrosis, hepatitis C virus infection, and hepatocellular carcinoma. Further, it summarizes the diverse liver-specific miRNAs, illustrating the potential merits and possible caveats of their utilization as noninvasive biomarkers and appealing therapeutic targets for liver illnesses.

Advances in Multi-Omics Applications in HBV-Associated Hepatocellular Carcinoma

Hepatitis B virus (HBV) specifically infects liver cells, leading to progressive liver cirrhosis and significantly increasing the risk of hepatocellular carcinoma (HCC). The maturity of sequencing technology, improvement in bioinformatics data analysis and progress of omics technologies had improved research efficiency. The occurrence and progression of HCC are affected by multisystem and multilevel pathological changes. With the application of single-omics technologies, including genomics, transcriptomics, metabolomics and proteomics in tissue and body fluid samples, and even the novel development of multi-omics analysis on a single-cell platform, HBV-associated HCC changes can be better analyzed. The review summarizes the application of single omics and combined analysis of multi-omics data in HBV-associated HCC and proposes the importance of multi-omics analysis in the type of HCC, which provide the possibility for the precise diagnosis and therapy of HBV-associated HCC.

LncRNA SNHG6 promotes G1/S-phase transition in hepatocellular carcinoma by impairing miR-204-5p-mediated inhibition of E2F1

Emerging evidence suggests that long noncoding RNAs (lncRNAs) function as competitive endogenous RNA (ceRNA) targeting proteins and genes; however, the role of lncRNAs in hepatocellular carcinoma (HCC) is not well understood. We investigated the mechanism by which lncRNA SNHG6 promotes the development of HCC. RT-qPCR revealed upregulated lncRNA SNHG6 in the HCC setting. Elevated SNHG6 expression was indicative of poor prognosis in patients with HCC. SNHG6 overexpression resulted in increased cyclin D1, cyclin E1, and E2F1 expression both in vitro and in vivo. SNHG6 also promoted HCC cell proliferation by enhancing G1-S phase transition in vitro. Dual luciferase reporter assays, RIP, and RNA pull-down assays demonstrated SNHG6 competitively bound to miR-204-5p and inhibited its expression preventing miR-204-5p from targeting E2F1. Overexpression of miR-204-5p abolished the effect of SNHG6. Our data suggest that SNHG6 functions as a ceRNA that targets miR-204-5p resulting in an increased E2F1 expression and enhanced G1-S phase transition, thereby promoting the tumorigenesis of HCC.

MicroRNA‑1271‑5p alleviates the malignant development of hepatitis B virus‑mediated liver cancer via binding to AQP5

Hepatitis B virus (HBV) is a leading cause of liver-related cancer. Progress has been made on the study of microRNA (miRNA or miR) function in HBV-related liver cancer. Hence, the objective of the present study was to determine the role and functional mechanism of miR-1271-5p in HBV-associated liver cancer. miR-1271-5p and aquaporin 5 (AQP5) expression at the mRNA level were measured by reverse transcription-quantitative PCR (RT-qPCR). The levels of hepatitis B e-antigen (HBeAg), hepatitis B surface antigen (HBsAg) and HBV DNA were assessed by ELISA or qPCR. Cell viability, apoptosis, migration and invasion were detected by Cell Counting Kit-8, flow cytometry or Transwell assay. The interaction of miR-1271-5p and AQP5 was predicted by TargetScan, and verified by Dual-luciferase reporter assay and RNA binding protein immunoprecipitation assay. The protein levels of AQP5, Bax, Bcl-2, cleaved-caspase-3 and proliferating cell nuclear antigen were quantified by western blot analysis. Nude mouse tumorigenicity assay was conducted to examine the role of miR-1271-5p in vivo. miR-1271-5p was downregulated, while AQP5 was upregulated in HBV-related liver cancer cells and tissues. Overexpression of miR-1271-5p or AQP5 knockdown inhibited the levels of HBeAg, HBsAg and HBV DNA, blocked cell viability, migration and invasion, and induced apoptosis. AQP5 was confirmed to be a direct target of miR-1271-5p, and miR-1271-5p exerted its role through targeting AQP5. Overexpression of miR-1271-5p impeded tumor growth in vivo by weakening the expression of AQP5. In conclusion, miR-1271-5p blocked the progression of HBV-induced liver cancer by competitively targeting AQP5.

Hepatitis B virus American genotypes: Pathogenic variants ?

Hepatitis B virus (HBV) chronic infection is responsible for almost 900.000 deaths each year, due to cirrhosis or hepatocellular carcinoma (HCC). Ten HBV genotypes have been described (A-J). HBV genotype F and H circulate in America. HBV genotypes have been further classified in subgenotypes. There is a strong correlation between the genetic admixture of the American continent and the frequency of genotypes F or H: a high frequency of these genotypes is found in countries with a population with a higher ratio of Amerindian to African genetic admixture. The frequency of occult HBV infection in Amerindian communities from Latin America seems to be higher than the one found in other HBV-infected groups, but its association with American genotypes is unknown. There is growing evidence that some genotypes might be associated with a faster evolution to HCC. In particular, HBV genotype F has been implicated in a frequent and rapid progression to HCC. However, HBV genotype H has been associated to a less severe progression of disease. This study reviews the diversity and frequency of autochthonous HBV variants in the Americas and evaluates their association to severe progression of disease. Although no significant differences were found in the methylation pattern between different genotypes and subgenotypes of the American types, basal core promoter mutations might be more frequent in some subgenotypes, such as F1b and F2, than in other American subgenotypes or genotype H. F1b and probably F2 may be associated with a severe presentation of liver disease as opposed to a more benign course for subgenotype F4 and genotype H. Thus, preliminary evidence suggests that not all of the American variants are associated with a rapid progression to HCC.

Advanced Therapeutics, Vaccinations, and Precision Medicine in the Treatment and Management of Chronic Hepatitis B Viral Infections; Where Are We and Where Are We Going?

The management of chronic hepatitis B virus (CHB) infection is an area of massive unmet clinical need worldwide. In spite of the development of powerful nucleoside/nucleotide analogue (NUC) drugs, and the widespread use of immune stimulators such as interferon-alpha (IFNα) or PEGylated interferon-alpha (PEG-IFNα), substantial improvements in CHB standards of care are still required. We believe that the future for CHB treatment now rests with advanced therapeutics, vaccination, and precision medicine, if all are to bring under control this most resilient of virus infections. In spite of a plethora of active drug treatments, anti-viral vaccinations and diagnostic techniques, the management of CHB infection remains unresolved. The reason for this is the very complexity of the virus replication cycle itself, giving rise to multiple potential targets for therapeutic intervention some of which remain very intractable indeed. Our review is focused on discussing the potential impact that advanced therapeutics, vaccinations and precision medicine could have on the future management of CHB infection. We demonstrate that advanced therapeutic approaches for the treatment of CHB, in the form of gene and immune therapies, together with modern vaccination strategies, are now emerging rapidly to tackle the limitations of current therapeutic approaches to CHB treatment in clinic. In addition, precision medicine approaches are now gathering pace too, starting with personalized medicine. On the basis of this, we argue that the time has now come to accelerate the design and creation of precision therapeutic approaches (PTAs) for CHB treatment that are based on advanced diagnostic tools and nanomedicine, and which could maximize CHB disease detection, treatment, and monitoring in ways that could genuinely eliminate CHB infection altogether.

The regulatory role of miR-107 in Coxsackie B3 virus replication

Coxsackie B3 virus (CVB3) is a member of small RNA viruses that belongs to the genus Enterovirus of the family Picornaviridae and CVB3 is the main pathogen of acute and chronic viral myocarditis. In this study RT-qPCR was used to determine the expression of miR-107 in CVB3-infected and uninfected HeLa cells. The experimental results show that the level of miR-107 began to rise at 4 h after the infection, and significantly boosted at 6 h. Based on the results of this experiment, we consider that miR-107 expression is related to CVB3 infection. In order to further clarify the effect of miR-107 in the process of CVB3 infection, we studied the effect of miR-107 upstream and downstream target genes on CVB3 replication. Levels of the target RNAs were detected by RT-qPCR after CVB3 infection, and the expression of CVB3 capsid protein VP1 by western blot analysis. Then the virus in the supernatant was quantitated via a viral plaque assay, reflecting the release of the virus. The experimental results showed that miRNA-107 expression is associated with CVB3 replication and proliferation, while KLF4 and BACE1 as the downstream of miR-107 weakened CVB3 replication. Overexpressions of KLF4 and BACE1 negatively regulated CVB3 replication, this effect on CVB3 was completely opposite to that of miR-107. Further experiments revealed that the upstream lncRNA004787, a new lncRNA that had not been reported, was located on chromosome 5, strand - from 37073250 to 37070908 (genome assembly: hg19). We sequenced and studied lncRNA004787 and found that it partially inhibited CVB3 replication. This prompted us to speculate that lncRNA004787 probably impacted the replication by other means. In conclusion, miR-107 interfered with CVB3 replication and release.

Downregulation of hsa-microRNA-204-5p and identification of its potential regulatory network in non-small cell lung cancer: RT-qPCR, bioinformatic- and meta-analyses

Background

Pulmonary malignant neoplasms have a high worldwide morbidity and mortality, so the study of these malignancies using microRNAs (miRNAs) has attracted great interest and enthusiasm. The aim of this study was to determine the clinical effect of hsa-microRNA-204-5p (miR-204-5p) and its underlying molecular mechanisms in non-small cell lung cancer (NSCLC).

Methods

Expression of miR-204-5p was investigated by real-time quantitative PCR (RT-qPCR). After data mining from public online repositories, several integrative assessment methods, including receiver operating characteristic (ROC) curves, hazard ratios (HR) with 95% confidence intervals (95% CI), and comprehensive meta-analyses, were conducted to explore the expression and clinical utility of miR-204-5p. The potential objects regulated and controlled by miR-204-5p in the course of NSCLC were identified by estimated target prediction and analysis. The regulatory network of miR-204-5p, with its target genes and transcription factors (TFs), was structured from database evidence and literature references.

Results

The expression of miR-204-5p was downregulated in NSCLC, and the downtrend was related to gender, histological type, vascular invasion, tumor size, clinicopathologic grade and lymph node metastasis (P<0.05). MiR-204-5p was useful in prognosis, but was deemed unsuitable at present as an auxiliary diagnostic or prognostic risk factor for NSCLC due to the lack of statistical significance in meta-analyses and absence of large-scale investigations. Gene enrichment and annotation analyses identified miR-204-5p candidate targets that took part in various genetic activities and biological functions. The predicted TFs, like MAX, MYC, and RUNX1, interfered in regulatory networks involving miR-204-5p and its predicted hub genes, though a modulatory loop or axis of the miRNA-TF-gene that was out of range with shortage in database prediction, experimental proof and literature confirmation.

Conclusions

The frequently observed decrease in miR-204-5p was helpful for NSCLC diagnosis. The estimated target genes and TFs contributed to the anti-oncogene effects of miR-204-5p.

Hepatitis B virus X protein upregulates alpha-fetoprotein to promote hepatocellular carcinoma by targeting miR-1236 and miR-329

Hepatitis B virus (HBV) infection is the most common cause of hepatocellular carcinoma (HCC) worldwide, wherein the expression of alpha-fetoprotein (AFP) is reactivated to promote tumorgenesis. Hepatitis B virus X protein (HBx) protein encoded by the HBV virus X gene has been considered to be oncogenic and implicated in hepatocarcinogenesis. However, the relationship between HBx and abnormal AFP expression in HCC is yet to be fully understood. To explore the potential regulation of HBx on AFP re-expression in HCC, 97 HCC samples of different etiologies were analyzed, and extremely higher serum AFP levels were found in patients with HBsAg⁺ . Analyses of HBV-related HCC specimens showed that the expression of AFP was negatively correlated with the levels of miR-1236 and miR-329. Further analyses indicated that HBx promotes the expression of AFP by orchestrating the levels of miR-1236 and miR-329 both in vitro and in vivo. Specifically, miR-1236 and miR-329 bind to the potential target sequences in AFP mRNA 3'-untranslated region to suppress its expression. HBx transfection resulted in the significant decrement of these microRNAs and increment of AFP expression. Moreover, AFP promotes the proliferation of hepatoma cells and attenuates the proapoptotic effect of chemotherapy agents. These findings revealed a novel regulatory mechanism of HBx on the abnormal AFP expression in HCC, which may provide a therapeutic approach for combating HBV-related HCC by targeting the regulation of AFP expression.

Circulating miRNA expression profile and bioinformatics analysis in patients with occult hepatitis B virus infection

Emerging suggest that microRNAs (miRNAs) play vital roles in the occurrence and development of hepatitis B virus (HBV) infectious disease. However, miRNAs in occult hepatitis B virus infection (OBI), a special stage of HBV infection, remain largely unknown. Herein, we conducted this study to identify differentially expressed miRNAs and then to investigate the potential roles of these miRNAs in OBI. Plasma miRNA expression profiles of three OBI patients and three healthy controls were analyzed with high through-put miRNA sequencing technology. Altered expression of miRNAs was further confirmed with reverse transcription quantitative polymerase chain reaction (qRT-PCR). Finally, bioinformatics analysis was conducted to investigate the involved pathways and target genes for these differentially expressed miRNAs. Totally, 32 differentially expressed miRNAs were identified between OBI and healthy controls by miRNA sequencing (fold change ≥ 1.5, P < .1, and counts per million reads ≥ 1), including 16 downregulated and 16 upregulated miRNAs. Differential expression of hsa-miR-486-5p, -25-3p, and -92a-3p and -1-3p was further validated by qRT-PCR analysis, which was consistent with miRNA sequencing analysis. Moreover, these four miRNAs might distinguish OBI from HCs efficiently. Bioinformatics analyses indicated that the differentially expressed miRNAs were primarily involved in various biological processes related to gene expression and transcription, cell development and metabolism, protein modification and kinase activity regulation, as well as multiple signaling pathways such as PI3K/Akt signaling pathway. This study provided a global view of miRNA expression in plasma from OBI patients. These differentially expressed miRNAs might play important roles in the development of OBI, which provided intriguing insights into the screening and molecular mechanism of OBI.

Circulating miR-122 Is a Predictor for Virological Response in CHB Patients With High Viral Load Treated With Nucleos(t)ide Analogs

Chronic hepatitis B (CHB) infection remains worldwide health problem. Antiviral treatment options for CHB patients include nucleos(t)ide analogs (NAs) and interferon. Most of the current biomarkers for predicting treatment response are virus-dependent. MicroRNA-122 is the most abundant liver-specific miRNA and has been identified involved in multiple liver physiology and pathology including hepatotropic virus infection. To identify the role of miR-122 in NA therapy, 80 CHB patients with high viral load (HVL) were enrolled and serum miR-122 levels at baseline, week 12 and week 24 were measured. Serum miR-122 levels were significantly lower in patients who developed virological response (VR), compared with non-VR group. Levels of miR-122 at week 12 and week 24 were determined to be independent prognostic indicators for a VR with satisfactory AUROC values at 0.812 and 0.800, respectively. During NA therapy, serum miR-122 level deceased steadily and an earlier reduction was observed in VR group, indicating early reduction of miR-122 level might increase the possibility of developing virological response. In conclusion, we identified the dynamic change of serum miR-122 level and miR-122 levels at week 12 and week 24 as independent predictors for VR in CHB patients with HVL treated with NAs.

miRNA-548ah promotes the replication and expression of hepatitis B virus by targeting histone deacetylase 4

AIM

Many studies have shown that some microRNAs (miRNAs) play an important role in the pathogenesis of chronic hepatitis B (CHB) infection. In this study, we aimed to explore the role and molecular mechanism of miRNA-548ah in the replication and expression of the hepatitis B virus (HBV).

MAIN METHODS

Overexpression and knockdown of miRNA-548ah were performed in three hepatoma cell lines with HBV replication and in a murine HBV model injected with adenovirus HBV vector. The effect of miRNA-548ah on its target gene, histone deacetylase (HDAC) 4, were confirmed in in vitro studies and further investigated in liver tissues from CHB patients.

KEY FINDINGS

miRNA-548ah significantly increased the expression of HBV in hepatoma cell lines and in a HBV mouse model. The expression level of covalently closed circular DNA (cccDNA) in the miRNA-548ah mimics group was significantly higher than the negative control group and significantly lower in the miRNA-548ah inhibitor group. The HBV core antigen promotes the expression of miRNA-548ah in hepatocytes. Finally, we observed a negative correlation between the expression of miRNA-548ah and HDAC4 in the liver tissue of patients with CHB.

SIGNIFICANCE

miRNA-548ah promoted the replication and expression of HBV through the regulation of the target gene, HDAC4. Inhibition of HDAC4 by miRNA-548ah might influence the deacetylation state of histones binding to cccDNA, thereby enhancing the replication of cccDNA. The HBV core antigen might increase the expression of miRNA-548ah. These results may provide new potential molecular targets for the prevention and treatment of CHB.

Zika virus E protein alters the properties of human fetal neural stem cells by modulating microRNA circuitry

Zika virus (ZV) infects neural stem cells (NSCs) and causes quiescence in NSCs, reducing the pool of brain cells, leading to microcephaly. Despite conscientious efforts, the molecular mechanisms for ZV-mediated effects on NSCs lack clarity. This study aimed to explore the underlying mechanisms for ZV-mediated induction of quiescence in the primary cultures of human fetal neural stem cells (fNSCs). We demonstrate that expression of ZV envelope (E) protein displays maximum quiescence in human fNSCs by accumulating cells in the G0/G1 phase of the cell cycle as compared to other non-structural proteins, viz. NS2A, NS4A and NS4B. E protein induces immature differentiation by induction of pro-neuronal genes in proliferating fNSCs, induces apoptosis in differentiating fNSCs 3 days post differentiation, and disrupts migration of cells from differentiating neurospheres. In utero electroporation of mouse brain with E protein shows drastic downregulation of proliferating cells in ventricular and subventricular zone regions. Global microRNA sequencing suggests that E protein modulates miRNA circuitry. Among differentially expressed miRNAs, we found 14 upregulated and 11 downregulated miRNAs. Mir-204-3p and mir-1273g-3p directly regulate NOTCH2 and PAX3 expression, respectively, by binding to their 3'UTR. Bioinformatic analysis using GO analysis for the targets of differentially expressed miRNAs revealed enrichment of cell cycle and developmental processes. Furthermore, WNT, CCKR, PDGF, EGF, p53, and NOTCH signaling pathways were among the top enriched pathways. Thus, our study provides evidence for the involvement of ZV E protein and novel insights into the molecular mechanism through identification of miRNA circuitry. Art work depicting the effect of Zika virus E protein on human fetal neural stem cells.

MicroRNA-204-3p inhibits lipopolysaccharide-induced cytokines in familial Mediterranean fever via the phosphoinositide 3-kinase γ pathway

Objective

We sought to identify the microRNA (miRNA) profile and potential biomarkers in FMF and to clarify their gene targets to elucidate the pathogenesis of FMF.

Methods

We performed an miRNA microarray using serum from FMF patients in attack and in remission. We then examined the expression of miRNAs in macrophages derived from THP-1 cells stimulated with toll-like receptor (TLR) ligands. Macrophages derived from THP-1 cells transfected with pre-miRNA were stimulated with lipopolysaccharides (LPSs) for the quantification of inflammatory cytokine production. To identify the target genes, we overexpressed their miRNA and performed a complementary DNA microarray. Transfection with reporter construct and the precursor miRNA was performed to confirm the suppression of target mRNA.

Results

We found that miR-204-3p was greatly decreased in the serum from FMF patients in attack. The expression of miR-204-3p was suppressed by LPS stimulation in the macrophages derived from THP-1 cells and the inhibition of miR-204-3p significantly induced the production of TLR4-related cytokines. The bioinformatic analysis showed that miR-204-3p is predicted to target genes implicated in the TLR pathway through the regulation of PI3Kγ signalling. The reporter assay revealed that miR-204-3p directly suppressed the luciferase activity of 3'-UTR of PIK3CG reporter construct. The inhibition of PI3Kγ resulted in decreased amounts of IL-6 and IL-12p40 in monocytes from FMF patients.

Conclusion

These data suggest that serum miR-204-3p has potential as a useful biomarker in FMF patients and that miR-204-3p serves as a suppressor of inflammatory cytokine production in FMF by targeting the PI3Kγ pathway.

Hepatitis B Virus Activates Signal Transducer and Activator of Transcription 3 Supporting Hepatocyte Survival and Virus Replication

BACKGROUND & AIMS

The human hepatitis B virus (HBV) is a major cause of chronic hepatitis and hepatocellular carcinoma, but molecular mechanisms driving liver disease and carcinogenesis are largely unknown. We therefore studied cellular pathways altered by HBV infection.

METHODS

We performed gene expression profiling of primary human hepatocytes infected with HBV and proved the results in HBV-replicating cell lines and human liver tissue using real-time polymerase chain reaction and Western blotting. Activation of signal transducer and activator of transcription (STAT3) was examined in HBV-replicating human hepatocytes, HBV-replicating mice, and liver tissue from HBV-infected individuals using Western blotting, STAT3-luciferase reporter assay, and immunohistochemistry. The consequences of STAT3 activation on HBV infection and cell survival were studied by chemical inhibition of STAT3 phosphorylation and small interfering RNA-mediated knockdown of STAT3.

RESULTS

Gene expression profiling of HBV-infected primary human hepatocytes detected no interferon response, while genes encoding for acute phase and antiapoptotic proteins were up-regulated. This gene regulation was confirmed in liver tissue samples of patients with chronic HBV infection and in HBV-related hepatocellular carcinoma. Pathway analysis revealed activation of STAT3 to be the major regulator. Interleukin-6-dependent and -independent activation of STAT3 was detected in HBV-replicating hepatocytes in cell culture and in vivo. Prevention of STAT3 activation by inhibition of Janus tyrosine kinases as well as small interfering RNA-mediated knockdown of STAT3-induced apoptosis and reduced HBV replication and gene expression.

CONCLUSIONS

HBV activates STAT3 signaling in hepatocytes to foster its own replication but also to prevent apoptosis of infected cells. This very likely supports HBV-related carcinogenesis.

Promising significance of the association of miR-204-5p expression with clinicopathological features of hepatocellular carcinoma

Decreased level of miR-204-5p has been documented in various malignancies. However, the expression and clinical significance of miR-204-5p in hepatocellular carcinoma has not been investigated. The aim of this study is to examine the relationship between miR-204-5p expression and clinicopathological features in hepatocellular carcinoma (HCC) as well as to predict the relevant signaling pathways. The miR-204-5p expression level was detected in HCC and in matched paraneoplastic liver from 95 formalin-fixed paraffin-embedded tissues by the real-time reverse transcription polymerized chain reaction (qRT-PCR). The association of miR-204-5p expression with clinicopathological features as well as the prognosis of HCC was examined. Public data portals including the Gene Expression Omnibus and The Cancer Genome Atlas were used to retrieve the HCC-related data in order to perform a comprehensive meta-analysis. Meanwhile, protein-protein interaction (PPI) and enrichment analyses were performed using predicted target genes. The relative expression of miR-204-5p was remarkably reduced in HCC than that in paraneoplastic hepatic tissues. In HCC, the miR-204-5p expression was downregulated in the metastasis, vasoinvasion, and advanced stage (III and IV) subgroups compared with their counterparts. Furthermore, the meta-analysis based on qRT-PCR data demonstrated that miR-204-5p was markedly downregulated in HCC with a standardized mean difference of -5.19 (P < .001). However, no significant association was observed between miR-204-5p and survival outcomes. The potential target genes of miR-204-5p were significantly enriched in several pathways which might be associated with HCC, such as "cell proliferation" from GO terms and "pathways in cancer" from the KEGG analysis. A PPI network of miR-204-5p potential target genes identified prospective core genes potentially involved in the regulation of HCC oncogenesis and progression. Our findings suggested that miR-204-5p might act as a tumor-suppressive gene in the tumorigenesis and progression of HCC via vital signaling pathways and that miR-204-5p could be regarded as a protective factor in HCC.

Circulating microRNAs as potential biomarkers of HBV infection persistence

OBJECTIVES

To investigate different microRNA (miRNA) expression profile in patients of hepatitis B virus (HBV) infection compared with virus spontaneous clearance ones, and try to find new biomarker for diagnosis and treatment assessment.

METHODS

miRNA expression profiling was analyzed in patients with HBV infection and patients with virus spontaneous clearance by Affymetrix Gene Chip miRNA 4.0 Arrays. The differently expressed miRNAs, as verified by RT-PCR, were analyzed and compared with each other in the two groups of patients.

RESULTS

Significant difference was found in the expression of miR-29b, miR-34, miR-4485, miR-3180, miR-125, miR-330-3p, miR-1468 in spontaneous clearance group and CHB group. miR-29b, miR-34, miR-4485 was significantly increased in CHB group, while miR-125, miR-330-3p, miR-1468, miR-3180 was significantly decreased. Correlation analysis indicate only miR-29b was positive correlation with HBsAg.

CONCLUSIONS

These results indicated above miRNAs may be associated with HBV infection persistence, and provided us new ideas for finding potential biomarkers.

The role of microRNAs in hepatocyte metabolism and hepatitis B virus replication

Though efficient vaccines against hepatitis B virus (HBV) and antiviral therapies are available, chronic HBV infection is still a global health problem. The process of HBV infection and HBV life cycle are extensively studied in last decades, however, the mechanisms of HBV-induced alterations of host cell metabolisms and host factors involved in modulating of viral replication are not fully understood. Thus, it is an important issue to examine these specific HBV-host interactions for development of novel strategies for antiviral therapies. Recently, microRNAs (miRNAs), a class of post-transcriptional regulatory small RNA, seem to be the relevant fine tuning factors of various cellular activities and pathways, including cell growth, metabolism, and viral replication. In this review, we summarize the up to date knowledge concerning the virus-host interactions and emphasizing on the role of miRNAs in regulation of HBV replication and host cell metabolism.