miR-21 Inhibition Reduces Liver Fibrosis and Prevents Tumor Development by Inducing Apoptosis of CD24+ Progenitor Cells

Significant response to pembrolizumab plus lenvatinib in Epstein-Barr-virus-associated intrahepatic cholangiocarcinoma: a case report

BACKGROUND

The prognosis for advanced intrahepatic cholangiocarcinoma (iCCA) is poor, and there remains an urgent need to develop efficient systemic therapy. The efficacy of Pembrolizumab immunotherapy combined with lenvatinibin in iCCA is still unclear. The role of Epstein-Barr-virus (EBV) as a biomarker in iCCA for response to immunotherapy needs further exploration.

CASE PRESENTATION

We report a case of a 60-year-old female with EBV-associated advanced iCCA (EBVaiCCA) who progressed after first-line therapy. She accomplished an available response to the combination therapy of pembrolizumab with lenvatinib, with overall survival of 20 months.

CONCLUSIONS

As far as we know, this is the first case report about the application of Pembrolizumab with lenvatinib for EBVaiCCA patients. This case indicates that the combination of immunotherapy and antiangiogenic therapy provides a glimmer of hope for advanced EBVaiCCA patients.

MiR-21 regulates skeletal muscle atrophy and fibrosis by targeting TGF-beta/SMAD7-SMAD2/3 signaling pathway

Long-term denervation-induced atrophy and fibrosis of skeletal muscle due to denervation leads to poor recovery of muscle function. Studies have shown that the transforming growth factor-β1 (TGF-β1)-Smad signaling pathway plays a central role in muscle atrophy and fibrosis. Recent studies demonstrate the role of microRNAs (miRs) in various pathological conditions, including muscle regeneration. miR-21 has been shown to play a dynamic role in inflammatory responses and in accelerating injury responses to fibrosis. We used both RNA sequencing and quantitative RT-PCR strategies to examine the alternations of miRNAs during denervation-induced gastrocnemius muscle atrophy and fibrosis. Our data showed that MiR-21 was upregulated in denervated gastrocnemius muscle tissue, and TGF-β1treatment increased miR-21 expression. Inhibition of miR-21 reduced gastrocnemius muscle fibrosis and significantly downregulated the expression of p-SMAD2/3 and the fibrosis-associated markers TGF-β1, connective tissue growth factor, alpha smooth muscle actin. Masson's trichrome staining revealed that atrophy and fibrosis in gastrocnemius muscle tissue were reduced in the miR-21 inhibition group compared to the control group. We confirmed that SMAD7 is a direct target of miR-21 using a dual luciferase assay. Furthermore, Immunofluorescence and Western blot analyses revealed that miR-21 inhibition reduced SMAD2/3 phosphorylation and nuclear translocation. While SMAD7-siRNA abolished the effect. Consequently, the discovery that miR-21 regulates the atrophy and fibrosis of the gastrocnemius muscle offers a possible therapeutic approach for their management.

Potential targets and therapeutics for cancer stem cell-based therapy against drug resistance in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common digestive malignancyin the world, which is frequently diagnosed at late stage with a poor prognosis. For most patients with advanced HCC, the therapeutic options arelimiteddue to cancer occurrence of drug resistance. Hepatic cancer stem cells (CSCs) account for a small subset of tumor cells with the ability of self-renewal and differentiationin HCC. It is widely recognized that the presence of CSCs contributes to primary and acquired drug resistance. Therefore, hepatic CSCs-targeted therapy is considered as a promising strategy to overcome drug resistance and improve therapeutic outcome in HCC. In this article, we review drug resistance in HCC and provide a summary of potential targets for CSCs-based therapy. In addition, the development of CSCs-targeted therapeuticsagainst drug resistance in HCC is summarized in both preclinical and clinical trials. The in-depth understanding of CSCs-related drug resistance in HCC will favor optimization of the current therapeutic strategies and gain encouraging therapeutic outcomes.

Functionalized Carbon Nanotubes for Delivery of Ferulic Acid and Diosgenin Anticancer Natural Agents

It was investigated whether loading multi-wall carbon nanotubes (CNTs) with two natural anticancer agents: ferulic acid (FUA) and diosgenin (DGN), may enhance the anticancer effect of these drugs. The CNTs were functionalized with carboxylic acid (CNTCOOH) or amine (CNTNH2), loaded with the above pro-drugs, as well as both combined and coated with chitosan or chitosan-stearic acid. Following physicochemical characterization, the drug-loading properties and kinetics of the drug's release were investigated. Their effects on normal human skin fibroblasts and MCF-7 breast carcinoma cells, HepG2 hepatocellular carcinoma cells, and A549 non-small-cell lung cancer cells were evaluated in vitro. Their actions at the molecular level were evaluated by assessing the expression of lncRNAs (HULC, HOTAIR, CCAT-2, H19, and HOTTIP), microRNAs (mir-21, mir-92, mir-145, and mir-181a), and proteins (TGF-β and E-cadherin) in HepG2 cells. The release of both pro-drugs depended on the glutathione concentration, coating, and functionalization. Release occurred in two stages: a no-burst/zero-order release followed by a sustained release best fitted to Korsmeyer-Peppas kinetics. The combined nanoformulation cancer inhibition effect on HepG2 cancer cells was more pronounced than for A549 and MCF7 cells. The combined nanoformulations had an additive impact followed by a synergistic effect, with antagonism demonstrated at high concentrations. The nanoformulation coated with chitosan and stearic acid was particularly successful in targeting HepG2 cells and inducing apoptosis. The CNT functionalized with carboxylic acid (CNTCOOH), loaded with both FUA and DGN, and coated with chitosan-stearic acid inhibited the expression of lncRNAs and modulated both microRNAs and proteins. Thus, nanoformulations composed of functionalized CNTs dual-loaded with FUA and DGN and coated with chitosan-stearic acid are a promising drug delivery system that enhances the activity of natural pro-drugs.

Non-coding RNA therapeutics: Towards a new candidate for arsenic-induced liver disease

Arsenic, a metalloid toxicant, has caused serious environmental pollution and is presently a global health issue. Long-term exposure to arsenic causes diverse organ and system dysfunctions, including liver disease. Arsenic-induced liver disease comprises a spectrum of liver pathologies, ranging from hepatocyte damage, steatosis, fibrosis, to hepatocellular carcinoma. Various mechanisms, including an imbalance in redox reactions, mitochondrial dysfunction and epigenetic changes, participate in the pathogenesis of arsenic-induced liver disease. Altered epigenetic processes involved in its initiation and progression. Dysregulated modulations of non-coding RNAs (ncRNAs), including miRNAs, lncRNAs and circRNAs, exert regulating effects on these processes. Here, we have reviewed the underlying pathogenic mechanisms that lead to progressive arsenic-induced liver disease, and we provide a discussion focusing on the effects of ncRNAs on dysfunctions in intercellular communication and on the activation of hepatic stellate cells and malignant transformation of hepatocytes. Further, we have discussed the roles of ncRNAs in intercellular communication via extracellular vesicles and cytokines, and have provided a perspective for the application of ncRNAs as biomarkers in the early diagnosis and evaluation of the pathogenesis of arsenic-induced liver disease. Further investigations of ncRNAs will help us to understand the nature of arsenic-induced liver disease and to identify biomarkers and therapeutic targets.

Cellular and Molecular Mechanisms of Liver Fibrosis in Patients with NAFLD

The expression of immune- and cancer-related genes was measured in liver biopsies from 107 NAFLD patients. The strongest difference in overall gene expression was between liver fibrosis stages F3 and F4, with 162 cirrhosis-associated genes identified. Strong correlations with fibrosis progression from F1 to F4 were observed for 91 genes, including CCL21, CCL2, CXCL6, and CCL19. In addition, the expression of 21 genes was associated with fast progression to F3/F4 in an independent group of eight NAFLD patients. These included the four chemokines, SPP1, HAMP, CXCL2, and IL-8. A six-gene signature including SOX9, THY-1, and CD3D had the highest performance detecting the progressors among F1/F2 NAFLD patients. We also characterized immune cell changes using multiplex immunofluorescence platforms. Fibrotic areas were strongly enriched in CD3+ T cells compared to CD68+ macrophages. While the number of CD68+ macrophages increased with fibrosis severity, the increase in CD3+ T-cell density was more substantial and progressive from F1 to F4. The strongest correlation with fibrosis progression was observed for CD3+CD45R0+ memory T cells, while the most significant increase in density between F1/F2 and F3/F4 was for CD3+CD45RO+FOXP3+CD8- and CD3+CD45RO-FOXP3+CD8- regulatory T cells. A specific increase in the density of CD68+CD11b+ Kupffer cells with liver fibrosis progression was also observed.

Spatial molecular and cellular determinants of STAT3 activation in liver fibrosis progression in non-alcoholic fatty liver disease

Background & Aims

The prevalence of non-alcoholic fatty liver disease (NAFLD) and its severe form, non-alcoholic steatohepatitis (NASH), is increasing. Individuals with NASH often develop liver fibrosis and advanced liver fibrosis is the main determinant of mortality in individuals with NASH. We and others have reported that STAT3 contributes to liver fibrosis and hepatocellular carcinoma in mice.

Methods

Here, we explored whether STAT3 activation in hepatocyte and non-hepatocyte areas, measured by phospho-STAT3 (pSTAT3), is associated with liver fibrosis progression in 133 patients with NAFLD. We further characterized the molecular and cellular determinants of STAT3 activation by integrating spatial distribution and transcriptomic changes in fibrotic NAFLD livers.Results: pSTAT3 scores in non-hepatocyte areas progressively increased with fibrosis severity (r = 0.53, p <0.001). Correlation analyses between pSTAT3 scores and expression of 1,540 immune- and cancer-associated genes revealed a large effect of STAT3 activation on gene expression changes in non-hepatocyte areas and confirmed a major role for STAT3 activation in fibrogenesis. Digital spatial transcriptomic profiling was also performed on 13 regions selected in hepatocyte and non-hepatocyte areas from four NAFLD liver biopsies with advanced fibrosis, using a customized panel of markers including pSTAT3, PanCK+CK8/18, and CD45. The regions were further segmented based on positive or negative pSTAT3 staining. Cell deconvolution analysis revealed that activated STAT3 was enriched in hepatic progenitor cells (HPCs) and sinusoidal endothelial cells. Regression of liver fibrosis upon STAT3 inhibition in mice with NASH resulted in a reduction of HPCs, demonstrating a direct role for STAT3 in HPC expansion.

Conclusion

Increased understanding of the spatial dependence of STAT3 signaling in NASH and liver fibrosis progression could lead to novel targeted treatment approaches.

Impact and implications

Advanced liver fibrosis is the main determinant of mortality in patients with NASH. This study showed using liver biopsies from 133 patients with NAFLD, that STAT3 activation in non-hepatocyte areas is strongly associated with fibrosis severity, inflammation, and progression to NASH. STAT3 activation was enriched in hepatic progenitor cells (HPCs) and sinusoidal endothelial cells (SECs), as determined by innovative technologies interrogating the spatial distribution of pSTAT3. Finally, STAT3 inhibition in mice resulted in reduced liver fibrosis and depletion of HPCs, suggesting that STAT3 activation in HPCs contributes to their expansion and fibrogenesis in NAFLD.

Circulating miRNAs associated with nonalcoholic fatty liver disease

MicroRNAs (miRNAs) are secreted from cells as either protein-bound or enclosed in extracellular vesicles. Circulating liver-derived miRNAs are modifiable by weight-loss or insulin-sensitizing treatments, indicating that they could be important biomarker candidates for diagnosis, monitoring, and prognosis in nonalcoholic liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Unfortunately, the noninvasive diagnosis of NASH and fibrosis remains a key challenge, which limits case finding. Current diagnostic guidelines, therefore, recommend liver biopsies, with risks of pain and bleeding for the patient and substantial healthcare costs. Here, we summarize mechanisms of RNA secretion and review circulating RNAs associated with NAFLD and NASH for their biomarker potential. Few circulating miRNAs are consistently associated with NAFLD/NASH: miR-122, miR-21, miR-34a, miR-192, miR-193, and the miR-17-92 miRNA-cluster. The hepatocyte-enriched miRNA-122 is consistently increased in NAFLD and NASH but decreased in liver cirrhosis. Circulating miR-34a, part of an existing diagnostic algorithm for NAFLD, and miR-21 are consistently increased in NAFLD and NASH. MiR-192 appears to be prominently upregulated in NASH compared with NAFDL, whereas miR-193 was reported to distinguish NASH from fibrosis. Various members of miRNA cluster miR-17-92 are reported to be associated with NAFLD and NASH, although with less consistency. Several other circulating miRNAs have been reported to be associated with fatty liver in a few studies, indicating the existence of more circulating miRNAs with relevant as diagnostic markers for NAFLD or NASH. Thus, circulating miRNAs show potential as biomarkers of fatty liver disease, but more information about phenotype specificity and longitudinal regulation is needed.

miRNA-21, which disrupts metabolic reprogramming to facilitate CD4+ T cell polarization toward the Th2 phenotype, accelerates arsenite-induced hepatic fibrosis

Elevated levels of arsenic may be present in groundwater, and long-term exposure to arsenic increases hepatic fibrosis. T helper 2 (Th2) cells are involved in the fibrotic cascade, and cell metabolism is a regulatory factor participating in CD4⁺ T cell differentiation and function. However, the mechanism for Th2 cell regulation of arsenite-induced hepatic fibrosis is not fully understood. In present study, for arsenite-fed mice, activated hepatic stellate cells may be involved in the infiltration of CD4⁺ T cells, accompanied by up-regulation of GATA3, a transcription factor, and IL-13, the major Th2 cytokine. Exposed to arsenite, Jurkat cells had increased aerobic glycolysis to promote the cell cycle and cell proliferation. Further, this process elevated levels of marker molecules, including those of the Th2 paradigm characterized by GATA3, IL-4, and IL-13. LX-2 cells were activated when treated with culture medium from Jurkat cells exposed to arsenite. miR-21 may be a therapeutic target for arsenite-induced hepatic fibrosis. In vitro, miR-21 knock-down caused inhibition of the PTEN/PI3K/AKT pathway induced by arsenite. It also reversed the elevated glycolysis and the accelerated cell cycle and cell proliferation. Indeed, this alteration led to diminished expression of GATA3, IL-4, and IL-13 in T cells differentiated under Th2 conditions, which inhibits activation of LX-2 cells. Consistent with the results in vitro, miR-21 knock-out in mice reversed hepatic fibrosis and attenuated the levels of GATA3 and IL-13 induced by arsenite. These findings indicate that miR-21 regulates the glycolysis of CD4⁺ T cells through the PTEN/PI3K/AKT pathway to accelerate the cell cycle, thereby facilitating CD4⁺ T cell polarization toward Th2 and releasing the fibrogenic factor IL-13, which participates in arsenite-associated hepatic fibrosis. Inhibition of Th2 polarization of CD4⁺T cells or miR-21 could be a therapeutic strategy to combat hepatic fibrosis caused by exposure to arsenic.

Pomegranate juice and punicalagin-mediated chemoprevention of hepatocellular carcinogenesis via regulating miR-21 and NF-κB-p65 in a rat model

Background

Hepatocellular carcinoma (HCC) is the most common neoplasm among primary liver malignancies, accounting for 70%–85% of total liver cancer cases worldwide. It is also the second-leading cause of cancer-related death worldwide. Recent research has investigated naturally occurring products high in polyphenolic compounds in the regression and prevention of HCC. This study investigated the chemoprevention effects of pomegranate juice (PJ) and punicalagin (PCG) against diethylnitrosamine (DENA)-induced hepatocarcinogenesis in male albino rats.

Methods

Animals were randomized into six groups and treated for 11 weeks as follows: group 1 was a negative control group, group 2 was treated orally with 10 mL PJ per kilogram body weight (kg bw), group 3 was treated orally with 18.5 mg PCG/kg bw, and groups 4–6 were injected with an intraperitoneal dose of DENA (50 mg/kg bw) weekly beginning in the third week. Group 4 was a HCC control (DENA-treated group), group 5 was HCC + PJ, and group 6 was HCC + PCG.

Results

PJ antagonized DENA-induced elevations of ALAT, TNF-α, NF-κB-p65, GST, MDA, and NO and restored total protein, IL-10, SOD, and CAT levels. Moreover, PJ resulted in downregulation of miR-21, Bcl-2, and Bcl-XL and an upregulation of caspase-3 and Bax mRNA expressions. These chemoprevention effects of PJ also alleviated the hepatic preneoplastic lesions induced by DENA. Although PCG treatment induced some modulation in DENA-treated rats, it did not show potent chemoprevention activity and induced some side effects.

Conclusion

Both of PJ and PCG downregulated miR-21 expression and triggered apoptosis. However, PJ was more effective than pure PCG in alleviating the hepatic antioxidant defense state and the inflammatory status. So, PJ was superior in prevention of DENA-induced hepatocellular carcinogenesis in rats than pure PCG.

Graphical Abstract

Non-Coding RNAs in Hepatocellular Carcinoma

Liver cancer ranks as the fourth leading cause of cancer-related deaths. Despite extensive research efforts aiming to evaluate the biological mechanisms underlying hepatocellular carcinoma (HCC) development, little has been translated towards new diagnostic and treatment options for HCC patients. Historically, the focus has been centered on coding RNAs and their respective proteins. However, significant advances in sequencing and RNA detection technologies have shifted the research focus towards non-coding RNAs (ncRNA), as well as their impact on HCC development and progression. A number of studies reported complex post-transcriptional interactions between various ncRNA and coding RNA molecules. These interactions offer insights into the role of ncRNAs in both the known pathways leading to oncogenesis, such as dysregulation of p53, and lesser-known mechanisms, such as small nucleolar RNA methylation. Studies investigating these mechanisms have identified prevalent ncRNA changes in microRNAs, snoRNAs, and long non-coding RNAs that can both pre- and post-translationally regulate key factors in HCC progression. In this review, we present relevant publications describing ncRNAs to summarize the impact of different ncRNA species on liver cancer development and progression and to evaluate recent attempts at clinical translation.

The Potential Role of Gut Microbial-Derived Exosomes in Metabolic-Associated Fatty Liver Disease: Implications for Treatment

The prevalence and incidence of metabolic-associated fatty liver disease (MAFLD), a clinically heterogeneous disease whose primary clinical therapies include dietary control and exercise therapy, is increasing worldwide and constitutes a significant medical burden. Gut microbes influence the physiopathological processes of the liver through different mechanisms based on the gut-liver axis. Exosomes are essential carriers of intercellular communication. Most previous studies have focused on adipocyte- and hepatocyte-derived exosomes, while the critical role of microbial-derived exosomes and the molecular mechanisms behind them in MAFLD have received little attention. Therefore, we searched and screened the latest relevant studies in the PubMeb database to elucidate the link between microbial-derived exosomes and the pathogenesis of MAFLD, mainly in terms of insulin resistance, intestinal barrier, inflammatory response, lipid metabolism, and liver fibrosis. The aim was to provide a theoretical framework and support for clinical protocols and innovative drug development.

ROLE OF MICRO RNA IN THE REGULATION OF CELL POLARIZATION IN HEPATOCELLULAR CARCINOMA

BACKGROUND

The occurrence of tissue scarring, and architecture-modifying signalling led to a tumorigenic microenvironment. Targeting specifically the biological mediators responsible for the physiological and morphological changes accommodating Hepatocellular carcinoma (HCC) growth may be the key for identifying a future HCC cure.

METHODS

Morphological and physiological features of cultured HepG2 cells in both stimulated recombinant human vascular endothelial growth factor (VEGF165), and unstimulated (control) conditions were assessed. Quantitative RT-PCR measured endogenous VEGF expression levels. The assessment of pro-angiogenic biological mediator (miR-296, miR-31, and miR-17) profiles was achieved by polarization-inducing VEGF165 stimulation followed by quantitative RT-PCR.

RESULTS

In-vitro conditions reproduced successfully the physiological environment leading to the occurrence of HCC, including the successful HepG2 polarization following VEGF stimulation. While endogenous VEGF production only occurs if complete polarization has been reached, the quantified biological mediator profiles determined here pointed at either possible early stages of depolarization or at the lack of tumorigenic potential of the HepG2 cells. All tested micro RNAs (miRs) displayed upregulated profiles, although the miR-296 was less amplified (3.78-fold as compared to control) than miR-31 or miR-17 (6.5- and 6.6-fold, respectively).

CONCLUSIONS

The findings surrounding miR-17 reproduce similar data reported in the literature; the unexpected high miR-31 expression was intriguing. Given HepG2 cells' minimal tumorigenic potential, the unexpected multi-fold upregulation of miR-31 may be a cause or a consequence of HepG2 cells' low tumorigenic potential. The exploration of miR-31 therapeutic potential may be a future rewarding endeavor.

Mir-21 Suppression Promotes Mouse Hepatocarcinogenesis

Simple Summary

Hepatocellular carcinoma (HCC) is a frequent cancer of the liver with limited therapeutic options. MicroRNAs are a class of small molecules regulating a wide range of cellular processes that are important for cancer development. Among these microRNAs, miR-21 is strongly upregulated in almost all human cancers including HCC, and is considered as a strong driver of cancer development, suggesting that its pharmacological inhibition might represent a potential therapy. In this study, we show that deletion of miR-21 in genetically engineered mice promotes instead the development of HCC in several mouse models of this liver cancer. We further show that the lack of miR-21 is associated with increases in the expression of oncogenes such as Cdc25a, subtle deregulations of the MAPK, HiPPO, and STAT3 signaling pathways, as well as alterations of the inflammatory/immune anti-tumoral responses in the liver, which overtime contribute to enhanced tumorigenesis and progression toward malignancy. These results call for cautiousness when considering miR-21 inhibition for therapeutic purposes in HCC.

Abstract

The microRNA 21 (miR-21) is upregulated in almost all known human cancers and is considered a highly potent oncogene and potential therapeutic target for cancer treatment. In the liver, miR-21 was reported to promote hepatic steatosis and inflammation, but whether miR-21 also drives hepatocarcinogenesis remains poorly investigated in vivo. Here we show using both carcinogen (Diethylnitrosamine, DEN) or genetically (PTEN deficiency)-induced mouse models of hepatocellular carcinoma (HCC), total or hepatocyte-specific genetic deletion of this microRNA fosters HCC development—contrasting the expected oncogenic role of miR-21. Gene and protein expression analyses of mouse liver tissues further indicate that total or hepatocyte-specific miR-21 deficiency is associated with an increased expression of oncogenes such as Cdc25a, subtle deregulations of the MAPK, HiPPO, and STAT3 signaling pathways, as well as alterations of the inflammatory/immune anti-tumoral responses in the liver. Together, our data show that miR-21 deficiency promotes a pro-tumoral microenvironment, which over time fosters HCC development via pleiotropic and complex mechanisms. These results question the current dogma of miR-21 being a potent oncomiR in the liver and call for cautiousness when considering miR-21 inhibition for therapeutic purposes in HCC.

Hepatic Cancer Stem Cells: Molecular Mechanisms, Therapeutic Implications, and Circulating Biomarkers

Hepatocellular carcinoma (HCC) is one of the deadliest cancers. HCC is associated with multiple risk factors and is characterized by a marked tumor heterogeneity that makes its molecular classification difficult to apply in the clinics. The lack of circulating biomarkers for the diagnosis, prognosis, and prediction of response to treatments further undermines the possibility of developing personalized therapies. Accumulating evidence affirms the involvement of cancer stem cells (CSCs) in tumor heterogeneity, recurrence, and drug resistance. Owing to the contribution of CSCs to treatment failure, there is an urgent need to develop novel therapeutic strategies targeting, not only the tumor bulk, but also the CSC subpopulation. Clarification of the molecular mechanisms influencing CSC properties, and the identification of their functional roles in tumor progression, may facilitate the discovery of novel CSC-based therapeutic targets to be used alone, or in combination with current anticancer agents, for the treatment of HCC. Here, we review the driving forces behind the regulation of liver CSCs and their therapeutic implications. Additionally, we provide data on their possible exploitation as prognostic and predictive biomarkers in patients with HCC.

Molecular mechanisms underlying curcumin-mediated microRNA regulation in carcinogenesis; Focused on gastrointestinal cancers

Curcumin is a bioactive ingredient found in the Rhizomes of Curcuma longa. Curcumin is well known for its chemopreventive and anti-cancer properties. Recent findings have demonstrated several pharmacological and biological impacts of curcumin, related to the control and the management of gastrointestinal cancers. Mechanistically, curcumin exerts its biological impacts via antioxidant and anti-inflammatory effects through the interaction with various transcription factors and signaling molecules. Moreover, epigenetic modulators such as microRNAs (miRNAs) have been revealed as novel targets of curcumin. Curcumin was discovered to regulate the expression of numerous pathogenic miRNAs in gastric, colorectal, esophageal and liver cancers. The present systematic review was performed to identify miRNAs that are modulated by curcumin in gastrointestinal cancers.

MicroRNA‑101 inhibits renal tubular epithelial‑to‑mesenchymal transition by targeting TGF‑β1 type I receptor

MicroRNAs (miRNAs/miRs) are key regulators of renal interstitial fibrosis (RIF). The present study was designed to identify miRNAs associated with the development of RIF, and to explore the ability of these identified miRNAs to modulate the renal tubular epithelial‑to‑mesenchymal transition (EMT) process. To this end, miRNAs that were differentially expressed between normal and fibrotic kidneys in a rat model of mercury chloride (HgCl₂)‑induced RIF were detected via an array‑based approach. Bioinformatics analyses revealed that miR‑101 was the miRNA that was most significantly downregulated in the fibrotic renal tissue samples, and this was confirmed by RT‑qPCR, which also demonstrated that this miRNA was downregulated in transforming growth factor (TGF)‑β1‑treated human proximal tubular epithelial (HK‑2) cells. When miR‑101 was overexpressed, this was sufficient to reverse TGF‑β1‑induced EMT in HK‑2 cells, leading to the upregulation of the epithelial marker, E‑cadherin, and the downregulation of the mesenchymal marker, α‑smooth muscle actin. By contrast, the downregulation of miR‑101 using an inhibitor exerted the opposite effect. The overexpression of miR‑101 also suppressed the expression of the miR‑101 target gene, TGF‑β1 type I receptor (TβR‑I), and thereby impaired TGF‑β1/Smad3 signaling, while the opposite was observed upon miR‑101 inhibition. To further confirm the ability of miR‑101 to modulate EMT, the HK‑2 cells were treated with the TβR‑I inhibitor, SB‑431542, which significantly suppressed TGF‑β1‑induced EMT in these cells. Notably, miR‑101 inhibition exerted a less pronounced effect upon EMT‑related phenotypes in these TβR‑I inhibitor‑treated HK‑2 cells, supporting a model wherein miR‑101 inhibits TGF‑β1‑induced EMT by suppressing TβR‑I expression. On the whole, the present study demonstrates that miR‑101 is capable of inhibiting TGF‑β1‑induced tubular EMT by targeting TβR‑I, suggesting that it may be an important regulator of RIF.

MicroRNAs as regulators, biomarkers and therapeutic targets in liver diseases

MicroRNAs (miRNAs) are small, non-coding RNAs that post-transcriptionally regulate gene expression by binding to specific mRNA targets and promoting their degradation and/or translational inhibition. miRNAs regulate both physiological and pathological liver functions. Altered expression of miRNAs is associated with liver metabolism dysregulation, liver injury, liver fibrosis and tumour development, making miRNAs attractive therapeutic strategies for the diagnosis and treatment of liver diseases. Here, we review recent advances regarding the regulation and function of miRNAs in liver diseases with a major focus on miRNAs that are specifically expressed or enriched in hepatocytes (miR-122, miR-194/192), neutrophils (miR-223), hepatic stellate cells (miR-29), immune cells (miR-155) and in circulation (miR-21). The functions and target genes of these miRNAs are emphasised in alcohol-associated liver disease, non-alcoholic fatty liver disease, drug-induced liver injury, viral hepatitis and hepatocellular carcinoma, as well liver fibrosis and liver failure. We touch on the roles of miRNAs in intercellular communication between hepatocytes and other types of cells via extracellular vesicles in the pathogenesis of liver diseases. We provide perspective on the application of miRNAs as biomarkers for early diagnosis, prognosis and assessment of liver diseases and discuss the challenges in miRNA-based therapy for liver diseases. Further investigation of miRNAs in the liver will help us better understand the pathogeneses of liver diseases and may identify biomarkers and therapeutic targets for liver diseases in the future.

Dairy consumption and hepatocellular carcinoma risk

This review provides epidemiological and translational evidence for milk and dairy intake as critical risk factors in the pathogenesis of hepatocellular carcinoma (HCC). Large epidemiological studies in the United States and Europe identified total dairy, milk and butter intake with the exception of yogurt as independent risk factors of HCC. Enhanced activity of mechanistic target of rapamycin complex 1 (mTORC1) is a hallmark of HCC promoted by hepatitis B virus (HBV) and hepatitis C virus (HCV). mTORC1 is also activated by milk protein-induced synthesis of hepatic insulin-like growth factor 1 (IGF-1) and branched-chain amino acids (BCAAs), abundant constituents of milk proteins. Over the last decades, annual milk protein-derived BCAA intake increased 3 to 5 times in Western countries. In synergy with HBV- and HCV-induced secretion of hepatocyte-derived exosomes enriched in microRNA-21 (miR-21) and miR-155, exosomes of pasteurized milk as well deliver these oncogenic miRs to the human liver. Thus, milk exosomes operate in a comparable fashion to HBV- or HCV- induced exosomes. Milk-derived miRs synergistically enhance IGF-1-AKT-mTORC1 signaling and promote mTORC1-dependent translation, a meaningful mechanism during the postnatal growth phase, but a long-term adverse effect promoting the development of HCC. Both, dietary BCAA abundance combined with oncogenic milk exosome exposure persistently overstimulate hepatic mTORC1. Chronic alcohol consumption as well as type 2 diabetes mellitus (T2DM), two HCC-related conditions, increase BCAA plasma levels. In HCC, mTORC1 is further hyperactivated due to RAB1 mutations as well as impaired hepatic BCAA catabolism, a metabolic hallmark of T2DM. The potential HCC-preventive effect of yogurt may be caused by lactobacilli-mediated degradation of BCAAs, inhibition of branched-chain α-ketoacid dehydrogenase kinase via production of intestinal medium-chain fatty acids as well as degradation of milk exosomes including their oncogenic miRs. A restriction of total animal protein intake realized by a vegetable-based diet is recommended for the prevention of HCC.

Notch Signaling Regulation in HCC: From Hepatitis Virus to Non-Coding RNAs

The Notch family includes evolutionary conserved genes that encode for single-pass transmembrane receptors involved in stem cell maintenance, development and cell fate determination of many cell lineages. Upon activation by different ligands, and depending on the cell type, Notch signaling plays pleomorphic roles in hepatocellular carcinoma (HCC) affecting neoplastic growth, invasion capability and stem like properties. A specific knowledge of the deregulated expression of each Notch receptor and ligand, coupled with resultant phenotypic changes, is still lacking in HCC. Therefore, while interfering with Notch signaling might represent a promising therapeutic approach, the complexity of Notch/ligands interactions and the variable consequences of their modulations raises concerns when performed in undefined molecular background. The gamma-secretase inhibitors (GSIs), representing the most utilized approach for Notch inhibition in clinical trials, are characterized by important adverse effects due to the non-specific nature of GSIs themselves and to the lack of molecular criteria guiding patient selection. In this review, we briefly summarize the mechanisms involved in Notch pathway activation in HCC supporting the development of alternatives to the γ-secretase pan-inhibitor for HCC therapy.

MicroRNA-21-Dependent Macrophage-to-Fibroblast Signaling Determines the Cardiac Response to Pressure Overload

Supplemental Digital Content is available in the text.

Background:

Cardiac macrophages (cMPs) are increasingly recognized as important regulators of myocardial homeostasis and disease, yet the role of noncoding RNA in these cells is largely unknown. Small RNA sequencing of the entire miRNomes of the major cardiac cell fractions revealed microRNA-21 (miR-21) as the single highest expressed microRNA in cMPs, both in health and disease (25% and 43% of all microRNA reads, respectively). MiR-21 has been previously reported as a key microRNA driving tissue fibrosis. Here, we aimed to determine the function of macrophage miR-21 on myocardial homeostasis and disease-associated remodeling.

Methods:

Macrophage-specific ablation of miR-21 in mice driven by Cx3cr1-Cre was used to determine the function of miR-21 in this cell type. As a disease model, mice were subjected to pressure overload for 6 and 28 days. Cardiac function was assessed in vivo by echocardiography, followed by histological analyses and single-cell sequencing. Cocultures of macrophages and cardiac fibroblasts were used to study macrophage-to-fibroblast signaling.

Results:

Mice with macrophage-specific genetic deletion of miR-21 were protected from interstitial fibrosis and cardiac dysfunction when subjected to pressure overload of the left ventricle. Single-cell sequencing of pressure-overloaded hearts from these mice revealed that miR-21 in macrophages is essential for their polarization toward a M1-like phenotype. Systematic quantification of intercellular communication mediated by ligand-receptor interactions across all cell types revealed that miR-21 primarily determined macrophage-fibroblast communication, promoting the transition from quiescent fibroblasts to myofibroblasts. Polarization of isolated macrophages in vitro toward a proinflammatory (M1-like) phenotype activated myofibroblast transdifferentiation of cardiac fibroblasts in a paracrine manner and was dependent on miR-21 in cMPs.

Conclusions:

Our data indicate a critical role of cMPs in pressure overload–induced cardiac fibrosis and dysfunction and reveal macrophage miR-21 as a key molecule for the profibrotic role of cMPs.

AntimiR-21 Prevents Myocardial Dysfunction in a Pig Model of Ischemia/Reperfusion Injury

BACKGROUND

miR-21 is a central regulator of cardiac fibrosis, and its inhibition in small-animal models has been shown to be an effective antifibrotic strategy in various organs, including the heart. Effective delivery of therapeutic antisense micro-ribonucleic acid (antimiR) molecules to the myocardium in larger organisms is challenging, though, and remains to be established for models of chronic heart failure.

OBJECTIVES

The aims of this study were to test the applicability and therapeutic efficacy of local, catheter-based delivery of antimiR-21 in a pig model of heart failure and determine its effect on the cardiac transcriptomic signature and cellular composition.

METHODS

Pigs underwent transient percutaneous occlusion of the left coronary artery and were followed up for 33 days. AntimiR-21 (10 mg) was applied by intracoronary infusion at days 5 and 19 after the injury. Cardiac function was assessed in vivo, followed by histological analyses and deep ribonucleic acid sequencing (RNA-seq) of the myocardium and genetic deconvolution analysis.

RESULTS

AntimiR-21 effectively suppressed the remodeling-associated increase of miR-21. At 33 days after ischemia/reperfusion injury, LNA-21-treated hearts exhibited reduced cardiac fibrosis and hypertrophy and improved cardiac function. Deep RNA-seq revealed a significant derepression of the miR-21 targetome in antimiR-21-treated myocardium and a suppression of the inflammatory response and mitogen-activated protein kinase signaling. A genetic deconvolution approach built on deep RNA-seq and single-cell RNA-seq data identified reductions in macrophage and fibroblast numbers as the key cell types affected by antimiR-21 treatment.

CONCLUSIONS

This study provides the first evidence for the feasibility and therapeutic efficacy of miR-21 inhibition in a large animal model of heart failure.

Notch signalling pathway in development of cholangiocarcinoma

Cholangiocarcinoma (CCA) comprises of extra-hepatic cholangiocarcinoma and intrahepatic cholangiocarcinoma cancers as a result of inflammation of epithelium cell lining of the bile duct. The incidence rate is increasing dramatically worldwide with highest rates in Eastern and South Asian regions. Major risk factors involve chronic damage and inflammation of bile duct epithelium from primary sclerosing cholangitis, chronic hepatitis virus infection, gallstones and liver fluke infection. Various genetic variants have also been identified and as CCA develops on the background of biliary inflammation, diverse range of molecular mechanisms are involved in its progression. Among these, the Notch signalling pathway acts as a major driver of cholangiocarcinogenesis and its components (receptors, ligands and downstream signalling molecules) represent a promising therapeutic targets. Gamma-Secretase Inhibitors have been recognized in inhibiting the Notch pathway efficiently. A comprehensive knowledge of the molecular pathways activated by the Notch signalling cascade as well as its functional crosstalk with other signalling pathways provide better approach in developing innovative therapies against CCA.

Potential role of miR-214 in β-catenin gene expression within hepatocellular carcinoma

MicroRNAs (miRNAs) are important gene regulators whose dysregulations can be involved in tumorigenesis. β-catenin, the main agent in the Wnt/β-catenin pathway, controls various genes and its over-expression has been discovered in different kinds of cancers including Hepatocellular Carcinoma (HCC). Extensive research demonstrated that the Wnt signaling is one of the major affected pathways in HCC. This study aimed to find miRNA targeting β-catenin gene by bioinformatic approaches and confirm this correlation to propose new therapeutic targets for HCC. Prediction of miRNAs targeting 3'-Untranslated Regions (UTR) of β-catenin mRNA, were done using different types of credible bioinformatic databases. The luciferase assay was also recruited for further confirmation of the bioinformatic predictions. In the first step, the expression of β-catenin was assessed in the HepG2 cell line by real-time PCR technique. Next, transduction of HepG2 cells were done by lentiviral vectors containing the desired miRNA. Then, the expression level of miRNA and the β-catenin gene were evaluated. Based on the results obtained from different bioinformatic databases, miR-214 was selected as the potential miRNA with the highest probability in targeting β-catenin. Furthermore, Luciferase assay results confirmed the accuracy of our bioinformatic prediction. In line with our hypothesis, after the overexpression of miR-214 in HepG2 cells, β-catenin gene expression was reduced significantly. Gathered results indicate the miRNAs role in the down-regulation of their target genes. Hence, the results propose that miR-214 can prevent HCC development by suppressing β-catenin and may supply a newfound approach towards HCC therapy in humans.

Fuzheng Huayu recipe, a traditional Chinese compound herbal medicine, attenuates renal interstitial fibrosis via targeting the miR-21/PTEN/AKT axis

OBJECTIVE

MicroRNAs (miRNAs) may be viable targets for treating renal interstitial fibrosis (RIF). Fuzheng Huayu recipe (FZHY), a traditional Chinese compound herbal medicine, is often used in China to treat fibrosis. This study sought to assess the mechanisms through which FZHY influences miRNAs to treat RIF.

METHODS

RIF was induced in rats by mercury chloride and treated with FZHY. Hydroxyproline content, Masson's staining and type I collagen expression were used to evaluate renal collagen deposition. Renal miRNA profiles were evaluated using a miRNA microarray. Those miRNAs that were differentially expressed following FZHY treatment were identified and subjected to bioinformatic analyses. The miR-21 target gene phosphatase and tensin homolog (PTEN) expression and AKT phosphorylation in kidney tissues were assessed via Western blotting. In addition, HK-2 human proximal tubule epithelial cells were treated using angiotensin II (Ang-II) to induce epithelial-to-mesenchymal transition (EMT), followed by FZHY exposure. miR-21 and PTEN expressions were evaluated via quantitative reverse transcription-polymerase chain reaction (qRT-PCR), while E-cadherin and α-smooth muscle actin (α-SMA) expressions were assessed by immunofluorescent staining and qRT-PCR. Western blotting was used to assess PTEN and AKT phosphorylation.

RESULTS

FZHY significantly decreased kidney collagen deposition, hydroxyproline content and type I collagen level. The miRNA microarray identified 20 miRNAs that were differentially expressed in response to FZHY treatment. Subsequent bioinformatic analyses found that miR-21 was the key fibrosis-related miRNA regulated by FZHY. FZHY also decreased PTEN expression and AKT phosphorylation in fibrotic kidneys. Results from in vitro tests also suggested that FZHY promoted E-cadherin upregulation and inhibited α-SMA expression in Ang-II-treated HK-2 cells, effectively reversing Ang-II-mediated EMT. We also determined that FZHY reduced miR-21 expression, increased PTEN expression and decreased AKT phosphorylation in these cells.

CONCLUSION

miR-21 is the key fibrosis-related miRNA regulated by FZHY. The ability of FZHY to modulate miR-21/PTEN/AKT signaling may be a viable approach for treating RIF.

Downregulation of Acat1 by miR-21 may participate in liver fibrosis upon chronic DDT exposure

The main objective of the present study was to investigate the toxic effect of long-term exposure to DDT (2,2-dichlorodiphenyl-1,1,1-trichloroethane) on rat livers. Female Wistar rats were treated with once-weekly i.p. doses of DDT (10 and 50 mg/kg) for 12 weeks. Histological analysis revealed significant changes in the liver structure, especially at a dose of 50 mg/kg, which consistent with a fibrotic state. Long-term DDT exposure increased micro RNA-21 (miR-21) level and decreased Acetyl-CoA acetyltransferase 1 (Acat1) mRNA and protein levels in a dose-dependent manner. A dual-luciferase reporter assay confirmed the regulation of the rat Acat1 3'-UTR by miR-21. Previous studies have described the involvement of ACAT1 in fibrogenesis; thus, regulation of the Acat1 gene by miR-21 may play a role in DDT exposure-mediated liver fibrosis.

Prospective Advances in Non-coding RNAs Investigation

Non-coding RNAs (ncRNAs) play significant roles in numerous physiological cellular processes and molecular alterations during pathological conditions including heart diseases, cancer, immunological disorders and neurological diseases. This chapter is focusing on the basis of ncRNA relation with their functions and prospective advances in non-coding RNAs particularly miRNAs investigation in the cardiovascular disease management.The field of ncRNAs therapeutics is a very fascinating and challenging too. Scientists have opportunity to develop more advanced therapeutics as well as diagnostic approaches for cardiovascular conditions. Advanced studies are critically needed to deepen the understanding of the molecular biology, mechanism and modulation of ncRNAs and chemical formulations for managing CVDs.

The Promising Role of miR-21 as a Cancer Biomarker and Its Importance in RNA-Based Therapeutics

MicroRNAs are small noncoding transcripts that posttranscriptionally regulate gene expression via base-pairing complementarity. Their role in cancer can be related to tumor suppression or oncogenic function. Moreover, they have been linked to processes recognized as hallmarks of cancer, such as apoptosis, invasion, metastasis, and proliferation. Particularly, one of the first oncomiRs found upregulated in a variety of cancers, such as gliomas, breast cancer, and colorectal cancer, was microRNA-21 (miR-21). Some of its target genes associated with cancer are PTEN (phosphatase and tensin homolog), PDCD4 (programmed cell death protein 4), RECK (reversion-inducing cysteine-rich protein with Kazal motifs), and STAT3 (signal transducer activator of transcription 3). As a result, miR-21 has been proposed as a plausible diagnostic and prognostic biomarker, as well as a therapeutic target for several types of cancer. Currently, research and clinical trials to inhibit miR-21 through anti-miR-21 oligonucleotides and ADM-21 are being conducted. As all of the evidence suggests, miR-21 is involved in carcinogenic processes; therefore, inhibiting it could have effects on more than one type of cancer. However, whether miR-21 can be used as a tissue-specific biomarker should be analyzed with caution. Consequently, the purpose of this review is to outline the available information and recent advances regarding miR-21 as a potential biomarker in the clinical setting and as a therapeutic target in cancer to highlight its importance in the era of precision medicine.

The Therapeutic Potential of MicroRNAs in Atrial Fibrillation

One of the most globally prevalent supraventricular arrhythmias is atrial fibrillation (AF). Knowledge of the structures and functions of messenger RNA (mRNA) has recently increased. It is no longer viewed as solely an intermediate molecule between DNA and proteins but has come to be seen as a dynamic and modifiable gene regulator. This new perspective on mRNA has led to rising interest in it and its presence in research into new therapeutic schemes. This paper, therefore, focuses on microRNAs (miRNAs), which are small noncoding RNAs that regulate posttranscriptional gene expression and play a vital role in the physiology and normative development of cardiovascular systems. This means they play an equally vital role in the development and progression of cardiovascular diseases. In recent years, multiple studies have pinpointed particular miRNA expression profiles as being associated with varying histological features of AF. These studies have been carried out in both animal models and AF patients. The emergence of miRNAs as biomarkers and their therapeutic potential in AF patients will be discussed in the body of this paper.

Animal Models of Hepatocellular Carcinoma Prevention

Hepatocellular carcinoma (HCC) is a deadly disease and therapeutic efficacy in advanced HCC is limited. Since progression of chronic liver disease to HCC involves a long latency period of a few decades, a significant window of therapeutic opportunities exists for prevention of HCC and improve patient prognosis. Nonetheless, there has been no clinical advancement in instituting HCC chemopreventive strategies. Some of the major challenges are heterogenous genetic aberrations of HCC, significant modulation of tumor microenvironment and incomplete understanding of HCC tumorigenesis. To this end, animal models of HCC are valuable tools to evaluate biology of tumor initiation and progression with specific insight into molecular and genetic mechanisms involved. In this review, we describe various animal models of HCC that facilitate effective ways to study therapeutic prevention strategies that have translational potential to be evaluated in a clinical context.

Activation of the oncogenic miR-21-5p promotes HCV replication and steatosis induced by the viral core 3a protein

BACKGROUND & AIMS

miR-21-5p is a potent oncogenic microRNA targeting many key tumour suppressors including phosphatase and tensin homolog (PTEN). We recently identified PTEN as a key factor modulated by hepatitis C virus (HCV) to promote virion egress. In hepatocytes, expression of HCV-3a core protein was sufficient to downregulate PTEN and to trigger lipid droplet accumulation. Here, we investigated whether HCV controls PTEN expression through miR-21-5p-dependent mechanisms to trigger steatosis in hepatocytes and to promote HCV life cycle.

METHODS

MiR-21-5p expression in HCV-infected patients was evaluated by transcriptome meta-analysis. HCV replication and viral particle production were investigated in Jc1-infected Huh-7 cells after miR-21-5p inhibition. PTEN expression and steatosis were assessed in HCV-3a core protein-expressing Huh-7 cells and in mouse primary hepatocytes having miR-21-5p inhibited or genetically deleted respectively. HCV-3a core-induced steatosis was assessed in vivo in Mir21a knockout mice.

RESULTS

MiR-21-5p expression was significantly increased in hepatic tissues from HCV-infected patients. Infection by HCV-Jc1, or transduction with HCV-3a core, upregulated miR-21-5p expression and/or activity in Huh-7 cells. miR-21-5p inhibition decreased HCV replication and release of infectious virions by Huh-7 cells. HCV-3a core-induced PTEN downregulation and steatosis were further prevented in Huh-7 cells following miR-21-5p inhibition or in Mir21a knockout mouse primary hepatocytes. Finally, steatosis induction by AAV8-mediated HCV-3a core expression was reduced in vivo in Mir21a knockout mice.

CONCLUSION

MiR-21-5p activation by HCV is a key molecular step, promoting both HCV life cycle and HCV-3a core-induced steatosis and may be among the molecular changes induced by HCV-3a to promote carcinogenesis.

Acrylamide induces HepG2 cell proliferation through upregulation of miR-21 expression

Acrylamide, a potential carcinogen, exists in carbohydrate-rich foods cooked at a high temperature. It has been reported that acrylamide can cause DNA damage and cytotoxicity. The present study aimed to investigate the potential mechanism of human hepatocarcinoma HepG2 cell proliferation induced by acrylamide and to explore the antagonistic effects of a natural polyphenol curcumin against acrylamide via miR-21. The results indicated that acrylamide (≤100 μmol/L) significantly increased HepG2 cell proliferation and miR-21 expression. In addition, acrylamide reduced the PTEN expression in protein level, while induced the expressions of p-AKT, EGFR and cyclin D1. The PI3K/AKT inhibitor decreased p-AKT protein expression and inhibited the proliferation of HepG2 cells. In addition, curcumin effectively reduced acrylamide-induced HepG2 cell proliferation and induced apoptosis through the expression of miR-21. In conclusion, the results showed that acrylamide increased HepG2 cell proliferation via upregulating miR-21 expression, which may be a new target for the treatment and prevention of cancer.

The role of oncogenic Notch2 signaling in cancer: a novel therapeutic target

Deregulated Notch signaling is a key factor thought to facilitate the stem-like proliferation of cancer cells, thereby facilitating disease progression. Four subtypes of Notch receptor have been described to date, with each playing a distinct role in cancer development and progression, therefore warranting a careful and comprehensive examination of the targeting of each receptor subtype in the context of oncogenesis. Clinical efforts to translate the DAPT, which blocks Notch signaling, have been unsuccessful due to a combination of serious gastrointestinal side effects and a lack of complete blocking efficacy. There is therefore a clear need to identify better therapeutic strategies for targeting and manipulating Notch signaling. Notch2 is a Notch receptor that is commonly overexpressed in a range of cancers, and which is linked to a unique oncogenic mechanism. Successful efforts to block Notch2 signaling will depend upon doing so both efficiently and specifically in patients. As such, in the present review we will explore the role of Notch2 signaling in the development and progression of cancer, and we will assess agents and strategies with the potential to effectively disrupt Notch2 signaling and thereby yield novel cancer treatment regimens.

microRNA-21 expressions impact on liver fibrosis in biliary atresia patients

OBJECTIVE

Biliary atresia (BA) is the most common cause of neonatal jaundice, characterized by progressive and rapid liver fibrosis. Recent studies have shown that microRNAs (miRNAs) contribute to the liver fibrogenesis. We investigated the miRNA-21 impact in liver fibrogenesis in Indonesian BA patients.

RESULTS

There were 5, 4, and 7 BA patients with type 2A, 2B, and 3, respectively. Quantitative real-time polymerase chain reaction (qPCR) showed that the miRNA-21 expression was significantly increased (18-fold) in BA patients compared to controls (- 4.4 ± 4.0 vs. - 0.2 ± 4.8; p = 0.041). Furthermore, the phosphatase and tensin homolog deleted on chromosome ten (PTEN) expression was significantly down-regulated (3.1-fold) in BA group compared to control group (0.2 ± 1.4 vs. - 1.4 ± 1.7; p = 0.036). The α-smooth muscle actin (α-SMA) expression was not statistically significantly different between groups (13.7 ± 3.8 vs. 15.0 ± 4.8; p = 0.87). Interestingly, the miRNA-21 expression was significantly lower (25-fold) in cirrhosis than non-cirrhosis BA patients (- 0.8 ± 2.2 vs. - 5.3 ± 3.9; p = 0.004). In conclusions, our study provides support for the association between miRNA-21 expression and liver cirrhosis in BA patients. Further study with a larger sample size of patients is important to confirm our results.

Eicosapentaenoic Acid Improves Hepatic Metabolism and Reduces Inflammation Independent of Obesity in High-Fat-Fed Mice and in HepG2 Cells

The prevalence of nonalcoholic fatty liver disease (NAFLD) is increasing worldwide, concurrent with increased obesity. Thus, there is urgent need for research that can lead to effective NAFLD prevention/treatment strategies. Omega-3 polyunsaturated fatty acids (n-3 PUFAs), including eicosapentaenoic acid (EPA), improve inflammation- and dyslipidemia-related metabolic disorders; however, mechanisms mediating the benefits of n-3 PUFAs in NAFLD treatment are less understood. We previously reported that EPA reversed obesity-induced hepatic steatosis in high-fat (HF)-fed B6 mice. Utilizing a combination of biochemical analyses of liver tissues from HF and HF-EPA-fed mice and a series of in vitro studies in tumor necrosis factor-alpha (TNF-α)-stimulated HepG2 cells, we dissect the mechanistic effects of EPA in reducing hepatic steatosis, including the role of EPA-targeted microRNAs (miRNA). With EPA, hepatic lipid metabolism was improved in HF-EPA mice, as indicated by decreased protein and messenger RNA (mRNA) levels of fatty acid synthase (FASN) and acetyl-CoA carboxylase (Acaca) gene, and increased mRNA levels for the peroxisome proliferator activated receptor-α (Pparα), and carnitine palmitoyltransferase (Cpt) 1a and 2 genes in the HF-EPA mice. Additionally, inflammation was reduced, as shown by decreased tumor necrosis factor-alpha (Tnfα) gene expression. Accordingly, EPA also significantly reduced FASN and ACACA mRNAs in human HepG2 cells. Glycolysis, estimated by extracellular acidification rate, was significantly reduced in HepG2 cells treated with EPA vs. vehicle. Furthermore, we identified several miRNAs that are regulated by EPA in mouse liver, including miR-19b-3p, miR-21a-5p, and others, which target lipid metabolism and inflammatory pathways. In conclusion, our findings provide novel mechanistic evidence for beneficial effects of EPA in NAFLD, through the identification of specific genes and miRNAs, which may be further exploited as future NAFLD therapies.

Circulating microRNAs as predictive biomarkers for liver disease progression of chronic hepatitis C (genotype-4) Egyptian patients

Egypt is one of the highest prevalence rates of hepatitis C virus (HCV) infection worldwide. HCV is among major reasons for chronic liver diseases. MicroRNA (miRNAs), small noncoding regulatory molecules play a key role in the pathogenesis of liver. Circulating miRNAs represent potential noninvasive biomarkers for diagnosis and monitoring patients with liver diseases progression. To investigate the potential role of circulating miRNAs for surveillance of liver disease progression, we assessed the expression of 20 liver-related miRNAs in sera of 47 chronic hepatitis C Egyptian patients compared with 25 controls using quantitative reverse-transcription polymerase chain reaction assay. The sensitivity and specificity were evaluated using receiver operating characteristic (ROC) curve. The correlations between their levels and the clinicopathological features were assessed. Fourteen miRNAs showed upregulation and six miRNAs showed downregulation. ROC curve analyses revealed that the explored miRNAs could serve as valuable biomarkers for chronic hepatitis with an area under the curve ranged from 0.708 (95% confidence interval [95% CI], 0.587 to 0.829; P = 0.004) for miR-199 up to 0.974 (95% CI, 0.943 to 1.00; P < 0.001) for miR-23b. The expression level of miR-21 demonstrated significant correlation with age, liver enzymes, ALT/AST, and α-fetoprotein level. AST level was directly correlated with miR-122, while an inversely correlated with miR-23b. Fibrosis and steatosis stages possessed positive correlation with miR-199 expression and negative correlation with miR-27a and miR-93. In conclusion, miR-23b and miR-106 might be a useful biomarker for chronic hepatitis C (CHC). MiR-27a, miR-93, and miR-199 might have a potential role in the progression of liver diseases. Unravel the role of these miRNAs in CHC patients might lead to precise prognosis and management.

Clinical significance of microRNA-21 expression in disease progression of patients with hepatocellular carcinoma

AIM

Aberrant microRNA (miR) expression is associated with hepatocellular carcinoma (HCC).

MATERIALS & METHODS

Here, we investigated the clinical significance of miR-21 and miR-31 for HCC-specific prognostic effect. HCC patients (n = 93) who underwent liver biopsy or surgical resection were enrolled, and HCC tissues and paired adjacent nontumor liver tissues were collected and analyzed for miRs expression.

RESULTS

MiR-21 expression was significantly upregulated in HCC tissues relative to nontumor tissues. Both miR-21 and miR-31 expression in HCC tissues did not predict overall survival; however, miR-21 was considered an independent predictor of disease progression together with portal vein thrombosis and higher Barcelona Clinical Liver Cancer stage.

CONCLUSION

Elevated miR-21 expression might represent a biomarker for HCC prognosis.

Potential Effect of Exosomes Derived from Cancer Stem Cells and MSCs on Progression of DEN-Induced HCC in Rats

Cross talk, mediated by exosomes, between normal stem cells and cancer stem cells (CSCs) in the tumor microenvironment has been given less attention so far. In addition, no publications are available in the literature that address the in vivo impact of exosomes derived from CSCs and mesenchymal stem cells (MSCs) on progression of long-term hepatocellular carcinoma (HCC). Herein, we hypothesized that transfer of exosomes among the cells in the HCC microenvironment could either induce or inhibit tumor growth and metastasis depending on their source. To check this hypothesis, we investigated the effect of exosomes coming from two different stem cell populations, hepatic CSCs and bone marrow (BM) MSCs, on progression of long-term DEN-induced HCC in rats and the involved underlying mechanisms. CSCs-exosomes induced a significant increase in liver relative weight and serum levels of cancer markers (AFP and GGT) and liver enzymes (ALT, AST, and ALP), intensive immunostaining for the HCC marker GST-P, and an increased number and area of tumor nodules as compared to HCC rats injected by PBS. CSCs-exosomes also decreased apoptosis (marked by downregulation of Bax and p53 and upregulation of Bcl2, and increased immunostaining of PCNA), increased angiogenetic activity (revealed by upregulation of VEGF), enhanced metastasis and invasiveness (indicated by upregulation of P13K and ERK proteins and their downstream target MMP9 and downregulation of TIMP1), and induced epithelial mesenchymal transition (marked by increased serum and hepatic level of TGFβ1 mRNA and protein). Notably, CSCs-exosomes also elevated HCC exosomal microRNA (miR) 21, exosomal long noncoding (lnc) RNA Tuc339, lncHEIH, and the HCC lncHOTAIR and decreased liver miR122 and HCC miRs (miR148a, miR16, and miR125b). All these cellular, functional, and molecular changes were reversed following injection of BM-MSCs-exosomes. However, both CSCs- and MSCs-exosomes failed to change the elevated oxidative stress or the inhibited antioxidant activities induced by HCC. Collectively, our results revealed a tumor stimulatory effect (induction of tumor growth, progression, and metastasis) for exosomes derived from CSCs and an inhibitory effect for exosomes derived from MSCs. These results provide valuable insight on the effect of CSCs- and MSCs-exosomes on HCC growth and progression in vivo, which may be helpful to understand the mechanism of HCC development.

Serum MicroRNA Levels as a Noninvasive Diagnostic Biomarker for the Early Diagnosis of Hepatitis B Virus-Related Liver Fibrosis

Background/Aims

To investigate the role of selected serum microRNA (miRNA) levels as potential noninvasive biomarkers for differentiating S0-S2 (early fibrosis) from S3-S4 (late fibrosis) in patients with a chronic hepatitis B virus (HBV) infection.

Methods

One hundred twenty-three treatment-naive patients with a chronic HBV infection who underwent a liver biopsy were enrolled in this study. The levels of selected miRNAs were measured using a real-time quantitative polymerase chain reaction assay. A logistic regression analysis was performed to assess factors associated with fibrosis progression. Receiver operating characteristic (ROC) curve and discriminant analyses validated these the ability of these predicted variables to discriminate S0-S2 from S3-S4.

Results

Serum miR-29, miR-143, miR-223, miR-21, and miR-374 levels were significantly downregulated as fibrosis progressed from S0-S2 to S3-S4 (p<0.05), but not miR-16. The multivariate logistic regression analysis identified a panel of three miRNAs and platelets that were associated with a high diagnostic accuracy in discriminating S0-S2 from S3-S4, with an area under the curve of 0.936.

Conclusions

The levels of the studied miRNAs, with the exception of miR-16, varied with fibrosis progression. A panel was identified that was capable of discriminating S0-S2 from S3-S4, indicating that serum miRNA levels could serve as a potential noninvasive biomarker of fibrosis progression.

Hepatitis B virus pathogenesis: Fresh insights into hepatitis B virus RNA

Hepatitis B virus (HBV) is still a worldwide health concern. While divergent factors are involved in its pathogenesis, it is now clear that HBV RNAs, principally templates for viral proteins and viral DNAs, have diverse biological functions involved in HBV pathogenesis. These functions include viral replication, hepatic fibrosis and hepatocarcinogenesis. Depending on the sequence similarities, HBV RNAs may act as sponges for host miRNAs and may deregulate miRNA functions, possibly leading to pathological consequences. Some parts of the HBV RNA molecule may function as viral-derived miRNA, which regulates viral replication. HBV DNA can integrate into the host genomic DNA and produce novel viral-host fusion RNA, which may have pathological functions. To date, elimination of HBV-derived covalently closed circular DNA has not been achieved. However, RNA transcription silencing may be an alternative practical approach to treat HBV-induced pathogenesis. A full understanding of HBV RNA transcription and the biological functions of HBV RNA may open a new avenue for the development of novel HBV therapeutics.

MicroRNA-21 and Dicer are dispensable for hepatic stellate cell activation and the development of liver fibrosis

Fibrosis and cancer represent two major complications of chronic liver disease. MicroRNAs have been implicated in the development of fibrosis and cancer, thus constituting potential therapeutic targets. Here, we investigated the role of microRNA-21 (miR-21), a microRNA that has been implicated in the development of fibrosis in multiple organs and has also been suggested to act as an "oncomir." Accordingly, miR-21 was the microRNA that showed the strongest up-regulation in activated hepatic stellate cells (HSCs) in multiple models of fibrogenesis, with an 8-fold to 24-fold induction compared to quiescent HSCs. However, miR-21 antisense inhibition did not suppress the activation of murine or human HSCs in culture or in liver slices. Moreover, genetic deletion of miR-21 in two independently generated knockout mice or miR-21 antisense inhibition did not alter HSC activation or liver fibrosis in models of toxic and biliary liver injury. Despite a strong up-regulation of miR-21 in injury-associated hepatocellular carcinoma and in cholangiocarcinoma, miR-21 deletion or antisense inhibition did not reduce the development of liver tumors. As inhibition of the most up-regulated microRNA did not affect HSC activation, liver fibrosis, or fibrosis-associated liver cancer, we additionally tested the role of microRNAs in HSCs by HSC-specific Dicer deletion. Although Dicer deletion decreased microRNA expression in HSCs and altered the expression of select genes, it only exerted negligible effects on HSC activation and liver fibrosis.

CONCLUSION

Genetic and pharmacologic manipulation of miR-21 does not inhibit the development of liver fibrosis and liver cancer. Moreover, suppression of microRNA synthesis does not significantly affect HSC phenotype and activation. (Hepatology 2018;67:2414-2429).

Personalized RNA Medicine for Pancreatic Cancer

Purpose: Since drug responses vary between patients, it is crucial to develop pre-clinical or co-clinical strategies that forecast patient response. In this study, we tested whether RNA-based therapeutics were suitable for personalized medicine by using patient-derived-organoid (PDO) and patient-derived-xenograft (PDX) models.Experimental Design: We performed microRNA (miRNA) profiling of PDX samples to determine the status of miRNA deregulation in individual pancreatic ductal adenocarcinoma (PDAC) patients. To deliver personalized RNA-based-therapy targeting oncogenic miRNAs that form part of this common PDAC miRNA over-expression signature, we packaged antimiR oligonucleotides against one of these miRNAs in tumor-penetrating nanocomplexes (TPN) targeting cell surface proteins on PDAC tumors.Results: As a validation for our pre-clinical strategy, the therapeutic potential of one of our nano-drugs, TPN-21, was first shown to decrease tumor cell growth and survival in PDO avatars for individual patients, then in their PDX avatars.Conclusions: This general approach appears suitable for co-clinical validation of personalized RNA medicine and paves the way to prospectively identify patients with eligible miRNA profiles for personalized RNA-based therapy. Clin Cancer Res; 24(7); 1734-47. ©2018 AACR.