Hepatitis C virus proteins modulate microRNA expression and chemosensitivity in malignant hepatocytes

Identification of exosomal microRNAs and related hub genes associated with imatinib resistance in chronic myeloid leukemia

Chemotherapy resistance is a major obstacle in cancer therapy, and identifying novel druggable targets to reverse this phenomenon is essential. The exosome-mediated transmittance of drug resistance has been shown in various cancer models including ovarian and prostate cancer models. In this study, we aimed to investigate the role of exosomal miRNA transfer in chronic myeloid leukemia drug resistance. For this purpose, firstly exosomes were isolated from imatinib sensitive (K562S) and resistant (K562R) chronic myeloid leukemia (CML) cells and named as Sexo and Rexo, respectively. Then, miRNA microarray was used to compare miRNA profiles of K562S, K562R, Sexo, Rexo, and Rexo-treated K562S cells. According to our results, miR-125b-5p and miR-99a-5p exhibited increased expression in resistant cells, their exosomes, and Rexo-treated sensitive cells compared to their sensitive counterparts. On the other hand, miR-210-3p and miR-193b-3p were determined to be the two miRNAs which exhibited decreased expression profile in resistant cells and their exosomes compared to their sensitive counterparts. Gene targets, signaling pathways, and enrichment analysis were performed for these miRNAs by TargetScan, KEGG, and DAVID. Potential interactions between gene candidates at the protein level were analyzed via STRING and Cytoscape software. Our findings revealed CCR5, GRK2, EDN1, ARRB1, P2RY2, LAMC2, PAK3, PAK4, and GIT2 as novel gene targets that may play roles in exosomal imatinib resistance transfer as well as mTOR, STAT3, MCL1, LAMC1, and KRAS which are already linked to imatinib resistance. MDR1 mRNA exhibited higher expression in Rexo compared to Sexo as well as in K562S cells treated with Rexo compared to K562S cells which may suggest exosomal transfer of MDR1 mRNA.

Hepatocellular Carcinoma Prevention in the Era of Hepatitis C Elimination

The hepatitis C virus (HCV), a single-stranded RNA virus belonging to the Flaviviridae family, is a major cause of hepatocellular carcinoma (HCC) worldwide. Tumors caused by HCC have an increased mortality rate globally, which is more accentuated in Western countries. The carcinogenic potential of this virus is mediated through a wide range of mechanisms, spanning from the induction of chronic inflammation to oxidative stress and deregulation of cellular pathways by viral proteins. As the number of new infections continues unabated, HCC-related mortality should be prioritized through early detection, continued prevention of HCV transmission, and treatment of HCV with safe and efficacious direct antiviral agents (DAAs). People who inject drugs (PWID) are a significant reservoir of new HCV infections globally, and in order to eliminate hepatitis C as a global health threat, as set out by the World Health Organization, an integrated approach based on the optimization of care delivery and increased access to harm reduction and treatment for PWID is needed. Thanks to the development of safe and effective antiviral agents, eradication of the infection is now possible in almost all treated patients, leading to a significant reduction but not the elimination of the risk for HCC in cured patients. This is particularly relevant among aged populations who have cofactors of morbidity known to accelerate HCC progression, such as diabetes, obesity, and excessive alcohol consumption. Given the restless accumulation of individuals with cured HCV infection, the implementation of risk-stratified surveillance programs becomes impellent from a cost-effectiveness perspective, whereas the availability of a performant biomarker to predict HCC in cured patients remains an unmet clinical need.

The rapidly evolving landscape of HCC: Selecting the optimal systemic therapy

Over the past years, there has been a remarkable advance in the systemic treatment options for advanced HCC. The overall survival has gradually increased over time, with larger benefits for patients with sensitive tumors and preserved liver function, the latter being an essential condition for the delivery of sequential lines of treatment and optimization of clinical outcomes. With the approval of new first-line agents and the introduction of immune checkpoint inhibitor-based therapies, the treatment landscape of advanced HCC is becoming wider than ever. Atezolizumab plus bevacizumab and, more recently, durvalumab plus tremelimumab have entered the clinical practice and are the current standard of care for treatment-naïve patients, surpassing sorafenib and lenvatinib monopoly. As no head-to-head comparisons are available among all the first-line treatment options, the recommendation for the most appropriate choice and sequence is patient-driven and integrates efficacy data with clinical comorbidities, background liver disease, and the safety profile of available drugs. In addition, predictive biomarkers for successful patients' stratification are yet to be available and constitute the focus of ongoing research. The treatment algorithm is likely to become even more complex since systemic therapeutic approaches are now being translated into earlier stages of the disease, with an impact on the evolution of the sequential treatment of patients with HCC.

Potential roles of core and core+1 proteins during the chronic phase of hepatitis C virus infection

The HCV Core protein is a multifunctional protein that interacts with many viral and cellular proteins. In addition to the encapsidation of the viral genome, it can disturb various cellular pathways and impede antiviral cellular responses such as interferon (IFN) production. The Core protein can also disrupt the functions of immune cells against HCV. The Core protein helps viral infection persistency by interfering with apoptosis. The Core+1 protein plays a significant role in inducing chronic HCV infection through diverse mechanisms. We review some of the mechanisms by which Core and Core+1 proteins facilitate HCV infection to chronic infection. These proteins could be considered for designing more sufficient treatments and effective vaccines against HCV.

Systemic therapies in hepatocellular carcinoma: Existing and emerging biomarkers for treatment response

Hepatocellular carcinoma (HCC) is the fifth most common malignancy and the third most common cause of cancer-related death worldwide. Due to asymptomatic patients in the early stage, most patients are diagnosed at an advanced stage and lose the opportunity for radical resection. In addition, for patients who underwent procedures with curative intent for early-stage HCC, up to 70% of patients may have disease recurrence within 5 years. With the advent of an increasing number of systemic therapy medications, we now have more options for the treatment of HCC. However, data from clinical studies show that with different combinations of regimens, the objective response rate is approximately 40%, and most patients will not respond to treatment. In this setting, biomarkers for predicting treatment response are of great significance for precise treatment, reducing drug side effects and saving medical resources. In this review, we summarized the existing and emerging biomarkers in the literature, with special emphasis on the pathways and mechanism underlying the prediction value of those biomarkers for systemic treatment response.

Modulation of pancreatic cancer cell sensitivity to FOLFIRINOX through microRNA-mediated regulation of DNA damage

FOLFIRINOX, a combination of chemotherapy drugs (Fluorouracil, Oxaliplatin, Irinotecan -FOI), provides the best clinical benefit in pancreatic ductal adenocarcinoma (PDAC) patients. In this study we explore the role of miRNAs (MIR) as modulators of chemosensitivity to identify potential biomarkers of response. We find that 41 and 84 microRNA inhibitors enhance the sensitivity of Capan1 and MiaPaCa2 PDAC cells respectively. These include a MIR1307-inhibitor that we validate in further PDAC cell lines. Chemotherapy-induced apoptosis and DNA damage accumulation are higher in MIR1307 knock-out (MIR1307KO) versus control PDAC cells, while re-expression of MIR1307 in MIR1307KO cells rescues these effects. We identify binding of MIR1307 to CLIC5 mRNA through covalent ligation of endogenous Argonaute-bound RNAs cross-linking immunoprecipitation assay. We validate these findings in an in vivo model with MIR1307 disruption. In a pilot cohort of PDAC patients undergoing FOLFIRONX chemotherapy, circulating MIR1307 correlates with clinical outcome.

Treatment for Viral Hepatitis as Secondary Prevention for Hepatocellular Carcinoma

Chronic infections with either hepatitis B or C virus (HBV or HCV) are among the most common risk factors for developing hepatocellular carcinoma (HCC). The hepatocarcinogenic potential of these viruses is mediated through a wide range of mechanisms, including the induction of chronic inflammation and oxidative stress and the deregulation of cellular pathways by viral proteins. Over the last decade, effective anti-viral agents have made sustained viral suppression or cure a feasible treatment objective for most chronic HBV/HCV patients. Given the tumorigenic potential of HBV/HCV, it is no surprise that obtaining sustained viral suppression or eradication proves to be effective in preventing HCC. This review summarizes the mechanisms by which HCV and HBV exert their hepatocarcinogenic activity and describes in detail the efficacy of anti-HBV and anti-HCV therapies in terms of HCC prevention. Although these treatments significantly reduce the risk for HCC in patients with chronic viral hepatitis, this risk is not eliminated. Therefore, we evaluate potential strategies to improve these outcomes further and address some of the remaining controversies.

MicroRNAs in helminth parasites: a systematic review

BACKGROUND

MicroRNAs (miRNAs) are about 22-nucleotide, small, non-coding RNAs that control gene expression post-transcriptionally. Helminth parasites usually express a unique repertoire of genes, including miRNAs, across different developmental stages with subtle regulatory mechanisms.

OBJECTIVE

There is a necessity to investigate the involvement of miRNAs in the development of parasites, host-parasite interaction, immune evasion and their abilities to govern infection in hosts. miRNAs present in helminth parasites have been summarized in the current systematic review (SR).

METHODS

Electronic databases, including PubMed, Scopus, ProQuest, Embase, and Google Scholar search engine, were searched to identify helminth miRNA studies published from February 1993 till December 2019. Only the published articles in English were included in the study.

RESULTS

A total of 1769 articles were preliminarily recorded. Following the strict inclusion and exclusion criteria, 105 studies were included in this SR. Most of these studies focused on the identification of miRNAs in helminth parasites and/or probing of differentially expressed host miRNA profiles in specific relevant tissues, while 12 studies aimed to detect parasite-derived miRNAs in host circulating system and 15 studies characterized extracellular vesicles (EV)-derived miRNAs secreted by parasites.

CONCLUSION

In the current SR, information regarding all miRNAs expressed in helminth parasites has been comprehensively provided and the utility of helminth parasites-derived miRNAs in diagnosis and control of parasitic infections has been discussed. Furthermore, functional studies on helminth-derived miRNAs have also been presented.

Sorafenib in the Treatment of Virus-Related HCC: Differences Between HCV and HBV

Hepatitis B- and C-virus (HBV and HCV) infections contribute to hepatocellular carcinoma (HCC) development through several different mechanisms. In addition to a diverse molecular background, HCC subtypes also show differences in their metabolic profiles, suggesting that prevention and treatment might require the integration of multiple different approaches. We here analyzed the response of two HCC cell lines representative of different virus-related etiology, namely Hep3B (HBV+) and HUH7 (permissive to HCV replication) to sorafenib treatment. Our findings suggest that virus-related specificities influence treatment response in HCC, along with molecular, metabolic and microenvironmental factors. These differences have to be taken into account in the design of future clinical trial aimed to improve HCC patients' outcome.

Oncogenic viruses and chemoresistance: What do we know?

Chemoresistance is often referred to as a major leading reason for cancer therapy failure, causing cancer relapse and further metastasis. As a result, an urgent need has been raised to reach a full comprehension of chemoresistance-associated molecular pathways, thereby designing new therapy methods. Many of metastatic tumor masses are found to be related with a viral cause. Although combined therapy is perceived as the model role therapy in such cases, chemoresistant features, which is more common in viral carcinogenesis, often get into way of this kind of therapy, minimizing the chance of survival. Some investigations indicate that the infecting virus dominates other leading factors, i.e., genetic alternations and tumor microenvironment, in development of cancer cell chemoresistance. Herein, we have gathered the available evidence on the mechanisms under which oncogenic viruses cause drug-resistance in chemotherapy.

MicroRNAs as Predictive Biomarkers of Resistance to Targeted Therapies in Gastrointestinal Tumors

The advent of precision therapies against specific gene alterations characterizing different neoplasms is revolutionizing the oncology field, opening novel treatment scenarios. However, the onset of resistance mechanisms put in place by the tumor is increasingly emerging, making the use of these drugs ineffective over time. Therefore, the search for indicators that can monitor the development of resistance mechanisms and above all ways to overcome it, is increasingly important. In this scenario, microRNAs are ideal candidate biomarkers, being crucial post-transcriptional regulators of gene expression with a well-known role in mediating mechanisms of drug resistance. Moreover, as microRNAs are stable molecules, easily detectable in tissues and biofluids, they are the ideal candidate biomarker to identify patients with primary resistance to a specific targeted therapy and those who have developed acquired resistance. The aim of this review is to summarize the major studies that have investigated the role of microRNAs as mediators of resistance to targeted therapies currently in use in gastro-intestinal neoplasms, namely anti-EGFR, anti-HER2 and anti-VEGF antibodies, small-molecule tyrosine kinase inhibitors and immune checkpoint inhibitors. For every microRNA and microRNA signature analyzed, the putative mechanisms underlying drug resistance were outlined and the potential to be translated in clinical practice was evaluated.

Cell death pathways and viruses: Role of microRNAs

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

Biology and Clinical Application of Regulatory RNAs in Hepatocellular Carcinoma

Most of the human genome consists of DNA genes that are translated into RNAs but not into proteins. These RNA molecules are named noncoding RNAs (ncRNA). While in the past it was thought that ncRNAs would be redundant without relevant functions, it is now well established that ncRNAs identify a class of regulatory molecules that finely tune cell homeostasis and are deregulated in disease states, including hepatocellular carcinoma (HCC). Of note, the number of ncRNAs within a cell increases progressively, with the complexity of the species indicating their essential role in the maintenance of regulatory networks that affect the intricacy of the organism. ncRNAs have been demonstrated to mediate HCC development and progression by affecting intrinsic cancer cell signaling and crosstalk between malignant cells and the microenvironment. Moreover, ncRNAs hold promise as clinical biomarkers, but further evidence is warranted before their translation and integration within clinical practice.

Circulating microRNAs associated with liver fibrosis in chronic hepatitis C patients

A major challenge in hepatitis C research is the detection of early potential for progressive liver disease. MicroRNAs (miRNAs) are small RNAs that regulate gene expression and can be biomarkers of pathological processes. In this study, we compared circulating miRNAs identified in hepatitis C virus (HCV)-infected patients presenting two extremes of liver disease: mild/moderate fibrosis and cirrhosis. The patients in the cirrhosis group subsequently developed hepatocellular carcinoma (HCC). We identified 163 mature miRNAs in the mild/moderate fibrosis group and 171 in the cirrhosis group, with 144 in common to both groups. Differential expression analysis revealed 5 upregulated miRNAs and 2 downregulated miRNAs in the cirrhosis group relative to the mild/moderate fibrosis group. Functional analyses of regulatory networks (target gene and miRNA) identified gene categories involved in cell cycle biological processes and metabolic pathways related to cell cycle, cancer, and apoptosis. These results suggest that the differentially expressed circulating miRNAs observed in this work (miR-215-5p, miR-483-5p, miR-193b-3p, miR-34a-5p, miR-885-5p, miR-26b-5p and miR -197-3p) may be candidates for biomarkers in the prognosis of liver disease.

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Circulating miRNome was performed in patients infected with HCV-1a or 1b.

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Mature miRNAs were identified in patients with mild/moderate fibrosis and cirrhosis.

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Five upregulated and two downregulated miRNAs were observed in the cirrhosis group.

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Regulatory networks identified gene categories involved in cell cycle.

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A routine baseline circulating biomarkers detection can have a prognostic value.

Modulation of Biliary Cancer Chemo-Resistance Through MicroRNA-Mediated Rewiring of the Expansion of CD133+ Cells

BACKGROUND AND AIMS

Changes in single microRNA (miRNA) expression have been associated with chemo-resistance in biliary tract cancers (BTCs). However, a global assessment of the dynamic role of the microRNome has never been performed to identify potential therapeutic targets that are functionally relevant in the BTC cell response to chemotherapy.

APPROACH AND RESULTS

High-throughput screening (HTS) of 997 locked nucleic acid miRNA inhibitors was performed in six cholangiocarcinoma cell lines treated with cisplatin and gemcitabine (CG) seeking changes in cell viability. Validation experiments were performed with mirVana probes. MicroRNA and gene expression was assessed by TaqMan assay, RNA-sequencing, and in situ hybridization in four independent cohorts of human BTCs. Knockout of microRNA was achieved by CRISPR-CAS9 in CCLP cells (MIR1249KO) and tested for effects on chemotherapy sensitivity in vitro and in vivo. HTS revealed that MIR1249 inhibition enhanced chemotherapy sensitivity across all cell lines. MIR1249 expression was increased in 41% of cases in human BTCs. In validation experiments, MIR1249 inhibition did not alter cell viability in untreated or dimethyl sulfoxide-treated cells; however, it did increase the CG effect. MIR1249 expression was increased in CD133+ biliary cancer cells freshly isolated from the stem cell niche of human BTCs as well as in CD133+ chemo-resistant CCLP cells. MIR1249 modulated the chemotherapy-induced enrichment of CD133+ cells by controlling their clonal expansion through the Wnt-regulator FZD8. MIR1249KO cells had impaired expansion of the CD133+ subclone and its enrichment after chemotherapy, reduced expression of cancer stem cell markers, and increased chemosensitivity. MIR1249KO xenograft BTC models showed tumor shrinkage after exposure to weekly CG, whereas wild-type models showed only stable disease over treatment.

CONCLUSIONS

MIR1249 mediates resistance to CG in BTCs and may be tested as a target for therapeutics.

A novel microRNA boosts hyper-β-oxidation of fatty acids in liver by impeding CEP350-mediated sequestration of PPARα and thus restricts chronic hepatitis C

Imbalance in lipid metabolism induces steatosis in liver during Chronic hepatitis C (CHC). Contribution of microRNAs in regulating lipid homoeostasis and liver disease progression is well established using small RNA-transcriptome data. Owing to the complexity in the development of liver diseases, the existence and functional importance of yet undiscovered regulatory miRNAs in disease pathogenesis was explored in this study using the unmapped sequences of the transcriptome data of HCV-HCC liver tissues following miRDeep2.pl pipeline. MicroRNA-c12 derived from the first intron of LGR5 of chromosome 12 was identified as one of the miRNA like sequences retrieved in this analysis that showed human specific origin. Northern blot hybridization has proved its existence in the hepatic cell line. Enrichment of premiR-c12 in dicer-deficient cells and miR-c12 in Ago2-RISC complex clearly suggested that it followed canonical miRNA biogenesis pathway and accomplished its regulatory function. Expression of this miRNA was quite low in CHC tissues than normal liver implying HCV-proteins might be regulating its biogenesis. Promoter scanning and ChIP analysis further revealed that under expression of p53 and hyper-methylation of STAT3 binding site upon HCV infection restricted its expression in CHC tissues. Centrosomal protein 350 (CEP350), which sequestered PPARα, was identified as one of the targets of miR-c12 using Miranda and validated by luciferase assay/western blot analysis. Furthermore, reduced triglyceride accumulation and enhanced PPARα mediated transcription of β-oxidation genes upon restoration of miR-c12 in liver cells suggested its role in lipid catabolism. Thus this study is reporting miR-c12 for the first time and showed its' protective role during chronic HCV infection.

Non-coding RNAs: Emerging Regulators of Sorafenib Resistance in Hepatocellular Carcinoma

As the first oral multi-target anti-tumor drug proved for the treatment of patients with advanced liver cancer in 2007, sorafenib has changed the landscape of advanced hepatocellular carcinoma (HCC) treatment. However, drug resistance largely hinders its clinical application. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs), and long non-coding (lncRNAs), have recently been demonstrated playing critical roles in a variety of cancers including HCC, while the mechanisms of ncRNAs in HCC sorafenib resistance have not been extensively characterized yet. Herein, we summarize the mechanisms of recently reported ncRNAs involved in sorafenib resistance and discuss the potential strategies for their application in the battle against HCC.

Sorafenib treatment on Chinese patients with advanced hepatocellular carcinoma: A study on prognostic factors of the viral and tumor status

Sorafenib is of proven efficacy in treating patients of hepatocellular carcinoma (HCC). Our study was aimed to determine the factors influence the sorafenib efficacy.We evaluated data of HCC patients receiving sorafenib from June 2012 to October 2016. All HCC cases were of the Barcelona Clinic Liver Cancer (BCLC) classification stage C. The exclusion criteria: those of BCLC classification stage A or B, with the absence or co-infection of hepatitis B (HBV) and hepatitis C (HCV). The presence of HBV, HCV, macoscopic vascular invasion (MVI) or extrahepatic spread (EHS) was recorded for each patient. Time-to-progression (TTP) and overall survival (OS) were analyzed.Among a total of 90 HCC patients, 48 (53.3%) had HBV infection, 42 (46.7%) had HCV infection, 51 (56.7%) had MVI, and 39 (43.3%) had EHS. Patients with HCV infection showed better TTP and OS than those with HBV infection. Patients with EHS had a longer TTP and OS than those with MVI. For patients with HBV infection, those with EHS had a longer TTP (mean 4.60 vs 2.64 months, P = .002) and OS (mean 6.65 vs 4.53 months, P = .045) compared to those with MVI. Among those with MVI, patients with HBV infection had a poorer TTP (mean 2.64 vs 4.74 months, P = .019) and shorter OS (mean 4.53 vs 7.00 months, P = .059) compared to those with HCV infection.HCC patients with HCV infection or with the presence of EHS showed better sorafenib efficacy.

The emerging role of microRNAs and long noncoding RNAs in drug resistance of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common malignancy worldwide and the second most lethal human cancer. A portion of patients with advanced HCC can significantly benefit from treatments with sorafenib, adriamycin, 5-fluorouracil and platinum drugs. However, most HCC patients eventually develop drug resistance, resulting in a poor prognosis. The mechanisms involved in HCC drug resistance are complex and inconclusive. Human transcripts without protein-coding potential are known as noncoding RNAs (ncRNAs), including microRNAs (miRNAs), small nucleolar RNAs (snoRNAs), long noncoding RNAs (lncRNAs) and circular RNA (circRNA). Accumulated evidences demonstrate that several deregulated miRNAs and lncRNAs are important regulators in the development of HCC drug resistance which elucidates their potential clinical implications. In this review, we summarized the detailed mechanisms by which miRNAs and lncRNAs affect HCC drug resistance. Multiple tumor-specific miRNAs and lncRNAs may serve as novel therapeutic targets and prognostic biomarkers for HCC.

MicroRNA-221 inhibits human papillomavirus 16 E1-E2 mediated DNA replication through activating SOCS1/Type I IFN signaling pathway

Human Papillomavirus (HPV) 16 infection has led to clinical disorders and is considered one of the important causes of human cervical cancer. Recently, microRNAs (miRNAs) have been proven to play an important role in many viral infections through regulating the Type I IFN immune response. However, reports concerning the role of miRNAs in HPV 16 infection are unclear. The aim of this study was to identify and evaluate the potential functions of miRNAs in HPV 16 replication and reveal the detailed mechanism for regulating IFN immune response. Using microarray and qRT-PCR assays, microRNA-221 (miR-221) was found to be significantly up-regulated in the serum samples from patients with HPV 16 infection, as well as in HPV 16-positive cervical cancer cells. miR-221 overexpression inhibited, while miR-221 knockdown facilitated HPV 16 E1-E2 mediated DNA replication in vitro. Moreover, overexpression of miR-221 was associated with upregulation of IFN-α and IFN-β at mRNA and protein levels in infected cells. Conversely, IFN-α and IFN-β mRNA or protein expression was significantly downregulated during inhibition of miR-221. Subsequently, we demonstrated that upregulation of miR-221 promoted the expression of representative interferon stimulated genes (ISGs) such as myxovirus protein A (MxA), 2',5'-oligoadenylate synthetases (OAS) and murine IFN-stimulated gene 15 (ISG15). In contrast, miR-221 inhibition significantly decreased ISGs expression. Furthermore, we found that suppressor of cytokine signaling 1 (SOCS1), a suppressor of interferon signaling pathway, was a direct target of miR-221 and overexpression of SOCS1 reversed the effects of miR-221 on the IFN-I response and HPV 16 E1-E2 mediated DNA replication. Collectively, the findings provide new evidence that miR-221 could inhibit HPV 16 E1-E2 mediated DNA replication through the SOCS1/Type I IFN signaling pathway suggesting it may be a novel anti-HPV therapeutic target.

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

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

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

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

Clinical significances and diagnostic utilities of both miR-215 and squamous cell carcinoma antigen-IgM versus alpha-fetoprotein in Egyptian patients with hepatitis C virus-induced hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. It has been widely established that the early detection of HCC enables more treatment options with improvements in prognosis and survival.

Objectives

The aim of this study was to assess the diagnostic accuracy of both circulating miR-215 and squamous cell carcinoma antigen-IgM (SCCA-IgM) as serum biomarkers for HCC by examining their diagnostic sensitivity, specificity, accuracy, and predictive values in hepatitis C virus (HCV)-induced HCC patients.

Subjects and methods

This study included 60 patients with HCV-related HCC. In addition, 60 patients with HCV-related liver cirrhosis (LC) and 60 apparently healthy subjects were involved, and served as diseased and healthy control groups, respectively. The relative expression levels of miR-215 were detected using quantitative real-time PCR. SCCA-IgM levels in serum were measured by enzyme immunoassay. We used receiver operating characteristic (ROC) curve to calculate the diagnostic accuracy against alpha-fetoprotein (AFP).

Results

Relative miR-215 expression levels increased the most in HCC patients compared to that in healthy or diseased controls (P<0.001). Serum concentration of SCCA-IgM was significantly higher in HCC group than that in the two control groups. We performed multivariate analysis using AFP level, focal lesion size, and portal vein thrombosis as independent variables. ROC curves showed that the optimum diagnostic miR-215 cutoff value for identifying HCC patients from cirrhotic ones was 417 (sensitivity, 97%; specificity, 91%) and for SCCA-IgM was 95 AU/mL (sensitivity, 92%; specificity, 98%). Moreover, the superiority of both miR-215 and SCCA-IgM to AFP is obvious in our study and this superiority is more evident in distinguishing HCC with AFP levels <200 ng/mL and HCC patients with small-sized focal lesions from cirrhotic patients.

Conclusion

Cell-free miR-215 and serum SCCA-IgM could be used for early diagnosis of HCC either each one as a single marker or with AFP complement measurement.

MicroRNAs as Mediators of Resistance Mechanisms to Small-Molecule Tyrosine Kinase Inhibitors in Solid Tumours

Receptor tyrosine kinases (RTKs) are widely expressed transmembrane proteins that act as receptors for growth factors and other extracellular signalling molecules. Upon ligand binding, RTKs activate intracellular signalling cascades, and as such are involved in a broad variety of cellular functions including differentiation, proliferation, migration, invasion, angiogenesis, and survival under physiological as well as pathological conditions. Aberrant RTK activation can lead to benign proliferative conditions as well as to various forms of cancer. Indeed, more than 70% of the known oncogene and proto-oncogene transcripts involved in cancer code for RTKs. Consequently, these receptors are broadly studied as targets in the treatment of different tumours, and a large variety of small-molecule tyrosine kinase inhibitors (TKIs) are approved for therapy. In most cases, patients develop resistance to the TKIs within a short time. MicroRNAs are short (18-22 nucleotides) non-protein-coding RNAs that fine-tune cell homeostasis by controlling gene expression at the post-transcriptional level. Deregulation of microRNAs is common in many cancers, and increasing evidence exists for an important role of microRNAs in the development of resistance to therapies, including TKIs. In this review we focus on the role of microRNAs in mediating resistance to small-molecule TKIs in solid tumours.

Non-Coding RNAs and Resistance to Anticancer Drugs in Gastrointestinal Tumors

Non-coding RNAs are important regulators of gene expression and transcription. It is well established that impaired non-coding RNA expression especially the one of long non-coding RNAs and microRNAs is involved in a number of pathological conditions including cancer. Non-coding RNAs are responsible for the development of resistance to anticancer treatments as they regulate drug resistance-related genes, affect intracellular drug concentrations, induce alternative signaling pathways, alter drug efficiency via blocking cell cycle regulation, and DNA damage response. Furthermore, they can prevent therapeutic-induced cell death and promote epithelial-mesenchymal transition (EMT) and elicit non-cell autonomous mechanisms of resistance. In this review, we summarize the role of non-coding RNAs for different mechanisms resulting in drug resistance (e.g., drug transport, drug metabolism, cell cycle regulation, regulation of apoptotic pathways, cancer stem cells, and EMT) in the context of gastrointestinal cancers.

Differential plasma microvesicle and brain profiles of microRNA in experimental cerebral malaria

BACKGROUND

Cerebral malaria (CM) is a fatal complication of Plasmodium infection, mostly affecting children under the age of five in the sub-Saharan African region. CM pathogenesis remains incompletely understood, although sequestered infected red blood cells, inflammatory cells aggregating in the cerebral blood vessels, and the microvesicles (MV) that they release in the circulation, have been implicated. Plasma MV numbers increase in CM patients and in the murine model, where blocking their release, genetically or pharmacologically, protects against brain pathology, suggesting a role of MV in CM neuropathogenesis. In this work, the microRNA (miRNA) cargo of MV is defined for the first time during experimental CM with the overarching hypothesis that this characterization could help understand CM pathogenesis.

RESULTS

The change in abundance of miRNA was studied following infection of CBA mice with Plasmodium berghei ANKA strain (causing experimental CM), and Plasmodium yoelii, which causes severe malaria without cerebral complications, termed non-CM (NCM). miRNA expression was analyzed using microarrays to compare MV from healthy (NI) and CM mice, yielding several miRNA of interest. The differential expression profiles of these selected miRNA (miR-146a, miR-150, miR-193b, miR-205, miR-215, miR-467a, and miR-486) were analyzed in mouse MV, MV-free plasma, and brain tissue by quantitative reverse transcription PCR (RT-qPCR). Two miRNA-miR-146a and miR-193b-were confirmed as differentially abundant in MV from CM mice, compared with NCM and NI mice. These miRNA have been shown to play various roles in inflammation, and their dysregulation during CM may be critical for triggering the neurological syndrome via regulation of their potential downstream targets.

CONCLUSIONS

These data suggest that, in the mouse model at least, miRNA may have a regulatory role in the pathogenesis of severe malaria.

Extracellular Vesicles as Carriers of Non-coding RNAs in Liver Diseases

Extracellular vesicles (EVs) are small membranous vesicles secreted from normal, diseased, and transformed cells in vitro and in vivo. EVs have been found to play a critical role in cell-to-cell communication by transferring non-coding RNAs (ncRNAs) including microRNAs (miRNAs), long ncRNAs (lncRNAs) and so on. Emerging evidence shows that transferring biological information through EVs to neighboring cells in intercellular communication not only keep physiological functions, but also participate in the pathogenesis of liver diseases. Liver diseases often promote release of EVs and/or in different cargo sorting into these EVs. Either of these modifications can promote disease pathogenesis. Given this fact, EV-associated ncRNAs, such as miR-192, miR-122 and lncRNA-ROR and so on, can serve as new diagnostic biomarkers and new therapeutic targets for liver disease, because altered EV-associated ncRNAs may reflect the underlying liver disease condition. In this review, we focus on understanding the emerging role of EV-associated ncRNAs in viral hepatitis, liver fibrosis, alcoholic hepatitis (AH), non-alcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC) and discuss their utility in biomarker discovery and therapeutics. A better understanding of this multifaceted pattern of communication between different type cells in liver may contribute to developing novel approaches for personalized diagnostics and therapeutics.

Crosstalk mechanisms between the WNT signaling pathway and long non-coding RNAs

The WNT/β-catenin signaling pathway controls a plethora of biological processes throughout animal development and adult life. Because of its fundamental role during animal lifespan, the WNT pathway is subject to strict positive and negative multi-layered regulation, while its aberrant activity causes a wide range of pathologies, including cancer. At present, despite the inroads into the molecules involved in WNT-mediated transcriptional responses, the fine-tuning of WNT pathway activity and the totality of its target genes have not been fully elucidated. Over the past few years, long non-coding RNAs (lncRNAs), RNA transcripts longer that 200nt that do not code for proteins, have emerged as significant transcriptional regulators. Recent studies show that lncRNAs can modulate WNT pathway outcome by affecting gene expression through diversified mechanisms, from the transcriptional to post-translational level. In this review, we selectively discuss those lncRNA-mediated mechanisms we believe the most important to WNT pathway modulation.

MicroRNA-193b-3p represses neuroblastoma cell growth via downregulation of Cyclin D1, MCL-1 and MYCN

Neuroblastoma is the most common diagnosed tumor in infants and the second most common extracranial tumor of childhood. The survival rate of patients with high-risk neuroblastoma is still very low despite intensive multimodal treatments. Therefore, new treatment strategies are needed. In recent years, miRNA-based anticancer therapy has received growing attention. Advances in this novel treatment strategy strongly depends on the identification of candidate miRNAs with broad-spectrum antitumor activity. Here, we identify miR-193b as a miRNA with tumor suppressive properties. We show that miR-193b is expressed at low levels in neuroblastoma cell lines and primary tumor samples. Introduction of miR-193b mimics into nine neuroblastoma cell lines with distinct genetic characteristics significantly reduces cell growth in vitro independent of risk factors such as p53 functionality or MYCN amplification. Functionally, miR-193b induces a G1 cell cycle arrest and cell death in neuroblastoma cell lines by reducing the expression of MYCN, Cyclin D1 and MCL-1, three important oncogenes in neuroblastoma of which inhibition has shown promising results in preclinical testing. Therefore, we suggest that miR-193b may represent a new candidate for miRNA-based anticancer therapy in neuroblastoma.

MIR21 Drives Resistance to Heat Shock Protein 90 Inhibition in Cholangiocarcinoma

BACKGROUND & AIMS

Cholangiocarcinomas (CCA) are resistant to chemotherapy, so new therapeutic agents are needed. We performed a screen to identify small-molecule compounds that are active against CCAs. Levels of microRNA 21 (MIR21 or miRNA21) are increased in CCAs. We investigated whether miRNA21 mediates resistance of CCA cells and organoids to HSP90 inhibitors.

METHODS

We performed a high-throughput screen of 484 small-molecule compounds to identify those that reduced viability of 6 human CCA cell lines. We tested the effects of HSP90 inhibitors on cells with disruption of the MIR21 gene, cells incubated with MIR21 inhibitors, and stable cell lines with inducible expression of MIR21. We obtained CCA biopsies from patients, cultured them as organoids (patient-derived organoids). We assessed their architecture, mutation and gene expression patterns, response to compounds in culture, and when grown as subcutaneous xenograft tumors in mice.

RESULTS

Cells with IDH1 and PBRM1 mutations had the highest level of sensitivity to histone deacetylase inhibitors. HSP90 inhibitors were effective in all cell lines, irrespective of mutations. Sensitivity of cells to HSP90 inhibitors correlated inversely with baseline level of MIR21. Disruption of MIR21 increased cell sensitivity to HSP90 inhibitors. CCA cells that expressed transgenic MIR21 were more resistant to HSP90 inhibitors than cells transfected with control vectors; inactivation of MIR21 in these cells restored sensitivity to these agents. MIR21 was shown to target the DnaJ heat shock protein family (Hsp40) member B5 (DNAJB5). Transgenic expression of DNAJB5 in CCA cells that overexpressed MIR21 re-sensitized them to HSP90 inhibitors. Sensitivity of patient-derived organoids to HSP90 inhibitors, in culture and when grown as xenograft tumors in mice, depended on expression of miRNA21.

CONCLUSIONS

miRNA21 appears to mediate resistance of CCA cells to HSP90 inhibitors by reducing levels of DNAJB5. HSP90 inhibitors might be developed for the treatment of CCA and miRNA21 might be a marker of sensitivity to these agents.

Regulation of insulin resistance and type II diabetes by hepatitis C virus infection: A driver function of circulating miRNAs

Hepatitis C virus (HCV) infection is a serious worldwide healthcare issue. Its association with various liver diseases including hepatocellular carcinoma (HCC) is well studied. However, the study on the relationship between HCV infection and the development of insulin resistance and diabetes is very limited. Current research has already elucidated some underlying mechanisms, especially on the regulation of metabolism and insulin signalling by viral proteins. More studies have emerged recently on the correlation between HCV infection‐derived miRNAs and diabetes and insulin resistance. However, no studies have been carried out to directly address if these miRNAs, especially circulating miRNAs, have causal effects on the development of insulin resistance and diabetes. Here, we proposed a new perspective that circulating miRNAs can perform regulatory functions to modulate gene expression in peripheral tissues leading to insulin resistance and diabetes, rather than just a passive factor associated with these pathological processes. The detailed rationales were elaborated through comprehensive literature review and bioinformatic analyses. miR‐122 was identified to be one of the most potential circulating miRNAs to cause insulin resistance. This result along with the idea about the driver function of circulating miRNAs will promote further investigations that eventually lead to the development of novel strategies to treat HCV infection‐associated extrahepatic comorbidities.

Sorafenib response in hepatocellular carcinoma: MicroRNAs as tuning forks

Hepatocellular carcinoma (HCC) is the primary liver malignancy that contributes towards the second most common cause of cancer-related mortality. The targeted chemotherapeutic agent, sorafenib, is known to show a statistically significant but limited overall survival advantage in advanced HCC. However, the individual patient response towards sorafenib varies drastically, with most experiencing stable disease and few with partial response; complete response is very rare. Progressive disease despite the treatment is also evident in many patients, indicating drug resistance. These varied responses have been linked with the modulation of several intracellular signaling pathways. Notably, the regulation of these pathways through diverse operating biomolecules, including microRNAs (miRNAs), is the focus of recent studies. MicroRNAs are tiny, non-coding RNA molecules that regulate the expression of several target genes. In addition, miRNAs are known to play a role in the progression of HCC carcinogenesis. Interestingly, miRNAs have also been identified to play differential roles in terms of sorafenib response in HCC such as biomarkers and functional modulation of cellular response to sorafenib, hence, they are also being therapeutically evaluated. This review outlines the role of reported miRNAs in different aspects of sorafenib response in HCC.

miR-21 expression and clinical outcome in locally advanced pancreatic cancer: exploratory analysis of the pancreatic cancer Erbitux, radiotherapy and UFT (PERU) trial

Background

Locally advanced pancreatic cancer (LAPC) is associated with high mortality, and biomarker-driven treatment approach is currently lacking. This study evaluated safety and efficacy of a combination approach of chemotherapy followed by chemo-radiotherapy (CRT) +/− cetuximab, and the prognostic role of miR-21 in patients with LAPC treated with a multimodality approach.

Patients and Methods

This was a randomised phase II trial in which patients with inoperable LAPC were offered gemcitabine and capecitabine (GEM-CAP) for 16 weeks. Patients with stable disease or response after GEM-CAP were randomised to capecitabine or UFT plus radiotherapy (RT) (A), or capecitabine or UFT plus cetuximab plus RT (B). The primary outcome of the study was overall survival (OS). Clinical outcome was compared according to baseline circulating miR-21 levels.

Results

17 patients were enrolled and treated with GEM-CAP, with 13 patients achieving disease control and being randomised to arms A (n:7) and B (n:6). After a median follow-up of 61.2 months, median progression free survival (PFS) was 10.4 months and 12.7 months, median OS was 15.8 months and 22.0 months in arms A and B respectively (p > 0.05). Patients with high baseline plasma miR-21 had worse PFS (3.5 vs. 12.7 months; p:0.032) and OS (5.1 vs 15.3 months; p:0.5) compared to patients with low miR-21. Circulating miR-21 levels reflected miR-21 expression within the tissues.

Conclusions

Addition of Cetuximab to CRT following induction chemotherapy did not improve survival. High miR-21 baseline plasma expression was associated with poor clinical outcome in LAPC patients treated with induction chemotherapy followed by chemo-radiotherapy.

Crosstalk between liver-related microRNAs and Wnt/β-catenin pathway in hepatocellular carcinoma patients

BACKGROUND AND STUDY AIMS

Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide with highest incidence in Asia and Africa. MicroRNAs (miRNAs), a class of non-coding single stranded RNA, which not only post transcriptionally regulate gene expression but also respond to signaling molecules to affect cell functions such as Wnt/β-catenin signaling specifically in HCC. The goal of this study is to investigate the crosstalk between Wnt/β-catenin signaling proteins and microRNAs expression in HCC patients.

PATIENTS AND METHODS

Fresh tissue samples of 30 primary HCC patients and 10 control subjects were included. Expression level of 13 different miRNAs (miR-10a- miR-106b- miR-99a- miR-148a- miR-125b- miR-30e- miR-183- miR-155- miR-199a- miR-199a3p- miR-24- miR-122 and miR-215) were examined using real-time PCR assay. Five proteins involved in the Wnt/β-catenin pathway (β-catenin, APC, c-myc, survivin and cyclin D1) were analysed by immunohistochemistry technique. The correlation between miRNAs expression levels with protein expressions was assessed.

RESULTS

Up-regulation of miR-155 and miR-183 was reported in HCC patients compared to normal controls and this up-regulation was significantly correlated with liver cirrhosis in the case of miR-155 (p<0.05) referring to their oncogenic activity. Down-regulation was observed for 11 miRNAs in HCC indicating their tumour suppression activity. MiRNA-10a, miR-30e, miR-215, miR-125b and miR-148a were significantly correlated with the expression of important players in Wnt/β-catenin pathway including β-catenin, APC and c-myc (p<0.05). Detailed analysis revealed that miR-215 is associated with the grade of the disease and miR-125b is associated with HCV infection.

CONCLUSION

Collectively, our data showed potential role of miR-10a, miR-30e, miR-215, miR-125b and miR-148a as important mediators in HCC progression. Furthermore, their association with Wnt/β-catenin cascade proteins could be exploited to develop new therapeutic target strategies in HCC.

Apoptosis signaling and BCL-2 pathways provide opportunities for novel targeted therapeutic strategies in hematologic malignances

Apoptosis is an essential biological process involved in tissue homeostasis and immunity. Aberrations of the two main apoptotic pathways, extrinsic and intrinsic, have been identified in hematological malignancies; many of these aberrations are associated with pathogenesis, prognosis and resistance to standard chemotherapeutic agents. Targeting components of the apoptotic pathways, especially the chief regulatory BCL-2 family in the intrinsic pathway, has proved to be a promising therapeutic approach for patients with hematological malignances, with the expectation of enhanced efficacy and reduced adverse events. Continuous investigations regarding the biological importance of each of the BCL-2 family components and the clinical rationale to achieve optimal therapeutic outcomes, using either monotherapy or in combination with other targeted agents, have generated inspiring progress in the field. Genomic, epigenomic and biological analyses including BH3 profiling facilitate effective evaluation of treatment response, cancer recurrence and drug resistance. In this review, we summarize the biological features of each of the components in the BCL-2 apoptotic pathways, analyze the regulatory mechanisms and the pivotal roles of BCL-2 family members in the pathogenesis of major types of hematologic malignances, and evaluate the potential of apoptosis- and BCL-2-targeted strategies as effective approaches in anti-cancer therapies.

Wnt signalling modulates transcribed-ultraconserved regions in hepatobiliary cancers

OBJECTIVE

Transcribed-ultraconserved regions (T-UCR) are long non-coding RNAs which are conserved across species and are involved in carcinogenesis. We studied T-UCRs downstream of the Wnt/β-catenin pathway in liver cancer.

DESIGN

Hypomorphic Apc mice (Apcfl/fl) and thiocetamide (TAA)-treated rats developed Wnt/β-catenin dependent hepatocarcinoma (HCC) and cholangiocarcinoma (CCA), respectively. T-UCR expression was assessed by microarray, real-time PCR and in situ hybridisation.

RESULTS

Overexpression of the T-UCR uc.158- could differentiate Wnt/β-catenin dependent HCC from normal liver and from β-catenin negative diethylnitrosamine (DEN)-induced HCC. uc.158- was overexpressed in human HepG2 versus Huh7 cells in line with activation of the Wnt pathway. In vitro modulation of β-catenin altered uc.158- expression in human malignant hepatocytes. uc.158- expression was increased in CTNNB1-mutated human HCCs compared with non-mutated human HCCs, and in human HCC with nuclear localisation of β-catenin. uc.158- was increased in TAA rat CCA and reduced after treatment with Wnt/β-catenin inhibitors. uc.158- expression was negative in human normal liver and biliary epithelia, while it was increased in human CCA in two different cohorts. Locked nucleic acid-mediated inhibition of uc.158- reduced anchorage cell growth, 3D-spheroid formation and spheroid-based cell migration, and increased apoptosis in HepG2 and SW1 cells. miR-193b was predicted to have binding sites within the uc.158- sequence. Modulation of uc.158- changed miR-193b expression in human malignant hepatocytes. Co-transfection of uc.158- inhibitor and anti-miR-193b rescued the effect of uc.158- inhibition on cell viability.

CONCLUSIONS

We showed that uc.158- is activated by the Wnt pathway in liver cancers and drives their growth. Thus, it may represent a promising target for the development of novel therapeutics.

HCV core inhibits hepatocellular carcinoma cell replicative senescence through downregulating microRNA-138 expression

Hepatitis C virus (HCV) infection is a major cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma (HCC). HCV core protein is considered as a positive regulator of telomerase activity. In this study, we focused on the deregulated microRNA-138 (miR-138) in HCV-associated HCC. Differential expression of miR-138 was determined by TaqMan quantitative real-time PCR. The target gene of miR-138 was verified by luciferase reporter assay, quantitative real-time PCR, and Western blotting. Moreover, three assays based on telomerase activity, cell proliferation, and senescence-associated β-galactosidase activity were performed. The correlation analysis revealed a significantly negative correlation between miR-138 and telomerase reverse transcriptase (TERT) mRNA expression in HCC. Further, we showed that mature HCV core protein of 173 amino acids, but not full-length form of 191 amino acids, suppressed miR-138 expression. TERT was verified as a direct target of miR-138 in HCC cells. Furthermore, TERT-targeting miR-138 supplementation can prevent HCV core protein from repressing HCC cell replicative senescence. Collectively, HCV core protein can enhance TERT protein expression through downregulating TERT-targeting miR-138 expression, which in turn inhibits HCC cell replicative senescence. This study may further help our understanding on the pathogenic mechanisms of HCV core protein in HCV-associated HCC development. KEY MESSAGE: miR-138 is downregulated in HCV-associated HCC. Mature HCV core protein plays a pathogenic role in suppressing miR-138 expression. Telomerase reverse transcriptase represents a direct target of miR-138 in HCC cells. miR-138 promotes HCC cell senescence, suggesting potential for HCC treatment.

Impact of Viral Status on Survival in Patients Receiving Sorafenib for Advanced Hepatocellular Cancer: A Meta-Analysis of Randomized Phase III Trials

Purpose Following the Sorafenib Hepatocellular Carcinoma Assessment Randomized Protocol (SHARP) trial, sorafenib has become the standard of care for patients with advanced unresectable hepatocellular carcinoma, but the relation between survival advantage and disease etiology remains unclear. To address this, we undertook an individual patient data meta-analysis of three large prospective randomized trials in which sorafenib was the control arm. Methods Of a total of 3,256 patients, 1,643 (50%) who received sorafenib were available. The primary end point was overall survival (OS). A Bayesian hierarchical approach for individual patient data meta-analyses was applied using a piecewise exponential model. Results are presented in terms of hazard ratios comparing sorafenib with alternative therapies according to hepatitis C virus (HCV) or hepatitis B virus (HBV) status. Results Hazard ratios show improved OS for sorafenib in patients who are both HBV negative and HCV positive (log [hazard ratio], -0.27; 95% CI, -0.46 to -0.06). Median unadjusted survival is 12.6 (11.15 to 13.8) months for sorafenib and 10.2 (8.88 to 12.2) months for "other" treatments in this subgroup. There was no evidence of improvement in OS for any other patient subgroups defined by HBV and HCV. Results were consistent across all trials with heterogeneity assessed using Cochran's Q statistic. Conclusion There is consistent evidence that the effect of sorafenib on OS is dependent on patients' hepatitis status. There is an improved OS for patients negative for HBV and positive for HCV when treated with sorafenib. There was no evidence of any improvement in OS attributable to sorafenib for patients positive for HBV and negative for HCV.

Exceptional serological and radiological response to sorafenib in 2 patients with advanced hepatocellular carcinoma and chronic hepatitis C viral infection: case report and review of the literature

Background

In patients with advanced hepatocellular carcinoma (HCC), the multikinase inhibitor sorafenib is the only systemic treatment that has been shown to increase overall survival. However, similar to other tyrosine kinase inhibitors, most patients achieve disease stabilisation radiologically, and only 2–3% of patients achieve a partial response. Recent exploratory subgroup analyses of the large phase 3 trials have demonstrated that patients with chronic hepatitis C virus (HCV) infection associated HCC survive longer than those who are negative for HCV. The mechanism underlying this currently remains unknown. A small number of cases of complete response to sorafenib treatment have now been reported worldwide, however a prolonged response has only been reported in 2 cases, both of whom had HCV-related HCC.

Case presentation

A 55 year old gentleman was diagnosed with hepatocellular carcinoma and concomitant chronic hepatitis C viral infection. He progressed following transarterial chemoemoblisation treatment and was commenced on sorafenib treatment. His serum alphafetoprotein level normalised within 2 months of treatment and he achieved an almost complete radiological response. This response was maintained for 20 months before the patient progressed. A 75 year old lady was diagnosed with advanced hepatocellular carcinoma and concomitant chronic hepatitis C viral infection. She was commenced on sorafenib treatment but required early dose reductions due to palmar plantar erythrodysesthesia, and liver decompensation. Despite this she achieved an excellent serological and radiological response that was maintained for 24 months.

Conclusions

Our two cases show that patients with HCV-associated HCC can attain excellent responses to sorafenib treatment that is durable. Furthermore, such exceptional responses can be achieved even with dose reductions and treatment breaks.

Hepatitis C virus suppresses Hepatocyte Nuclear Factor 4 alpha, a key regulator of hepatocellular carcinoma

Hepatitis C Virus (HCV) infection presents with a disturbed lipid profile and can evolve to hepatic steatosis and hepatocellular carcinoma (HCC). Hepatocyte Nuclear Factor 4 alpha (HNF4α) is the most abundant transcription factor in the liver, a key regulator of hepatic lipid metabolism and a critical determinant of Epithelial to Mesenchymal Transition and hepatic development. We have previously shown that transient inhibition of HNF4α initiates transformation of immortalized hepatocytes through a feedback loop consisting of miR-24, IL6 receptor (IL6R), STAT3, miR-124 and miR-629, suggesting a central role of HNF4α in HCC. However, the role of HNF4α in Hepatitis C Virus (HCV)-related hepatocarcinoma has not been evaluated and remains controversial. In this study, we provide strong evidence suggesting that HCV downregulates HNF4α expression at both transcriptional and translational levels. The observed decrease of HNF4α expression correlated with the downregulation of its downstream targets, HNF1α and MTP. Ectopic overexpression of HCV proteins also exhibited an inhibitory effect on HNF4α levels. The inhibition of HNF4α expression by HCV appeared to be mediated at transcriptional level as HCV proteins suppressed HNF4α gene promoter activity. HCV also up-regulated IL6R, activated STAT3 protein phosphorylation and altered the expression of acute phase genes. Furthermore, as HCV triggered the loss of HNF4α a consequent change of miR-24, miR-629 or miR-124 was observed. Our findings demonstrated that HCV-related HCC could be mediated through HNF4α-microRNA deregulation implying a possible role of HNF4α in HCV hepatocarcinogenesis. HCV inhibition of HNF4α could be sustained to promote HCC.

Erratum to: Negative feedback of miR-29 family TET1 involves in hepatocellular cancer

Primary hepatocellular carcinoma (HCC) is the most common form of liver cancer and is one of the most common malignancies worldwide. Tumor suppressor gene silencing through DNA methylation contributes to cancer formation. The ten-eleven translocations (TET) family of α-ketogluta-rate-dependent dioxygenases catalyzes the sequential oxidation of 5-methylcytosine to 5-hydroxymethyl-cytosine, 5-formylcytosine and 5-carboxylcytosine, leading to eventual DNA demethylation. MicroRNAs are an abundant class of 17-25 nucleotides small noncoding RNAs, identified as important regulators of many diverse biological processes. In this study, we showed that TET1 expression was obviously reduced in the majority of examined HCC tissues. And we further investigated the expression and functional involvement of TET1 in proliferation, migration and invasion and determined that TET1 may function as a tumor suppressor. miR-29b was proved to inhibit metastasis through the targeting of TET1, indicating that downregulation of miR-29 may involve in HCC carcinogenesis and progression through potentiation of TET1 expression. Thus, we elucidated the roles of feedback of miR-29-TET1 downregulation in HCC development and suggested a potential target in identification of the prognosis and application of cancer therapy for HCC patients.

Relation between microRNAs and Apoptosis in Hepatocellular Carcinoma

AIM:

To determine the relation between serum microRNAs and apoptotic markers as regards development of HCC to understand the underlying mechanism of HCV related hepatocarcinogenesis.

PATIENTS AND METHODS:

A total of 65 serum samples (25 samples from controls, 20 samples from hepatitis and 20 samples from HCC patients) were collected for miRNAs (mir 21, mir 199-a, and mir 155) detection. Human Programmed cell death protein-4 (PDCD-4) and Human Cytochrome-C (CYT-C) were determined.

RESULTS:

miRNAs 21 and 155 were over expressed in sera of patients with HCC compared to patients with chronic hepatitis (p < 0.0001). While serum means values of miR 199a was significantly decreased among HCC group patients when compared to patients with chronic hepatitis (p < 0.0001). The serum levels of PCDC4 and CYTC were increased in patients with HCC when compared to chronic hepatitis patients. They were also increased in patients with chronic hepatitis when compared to controls (p < 0.05, significant). There was direct correlations between apoptotic markers and oncomirs miRNAs 21 and 155 while apoptotic markers were inversely correlated with miRNA 199-a.

CONCLUSION:

Both microRNAs and apoptotic markers have roles in HCC pathogenesis. It seems that oncogenic microRNAs induce liver carcinogenesis in HCV patients irrespective of suppression of apoptosis.

MicroRNA expression analysis in high fat diet-induced NAFLD-NASH-HCC progression: study on C57BL/6J mice

Background

Hepatocellular carcinoma (HCC) is the most common malignant tumor of the liver. Non-alcoholic fatty liver disease (NAFLD) is a frequent chronic liver disorder in developed countries. NAFLD can progress through the more severe non alcoholic steatohepatitis (NASH), cirrhosis and, lastly, HCC. Genetic and epigenetic alterations of coding genes as well as deregulation of microRNAs (miRNAs) activity play a role in HCC development. In this study, the C57BL/6J mouse model was long term high-fat (HF) or low-fat (LF) diet fed, in order to analyze molecular mechanisms responsible for the hepatic damage progression.

Methods

Mice were HF or LF diet fed for different time points, then plasma and hepatic tissues were collected. Histological and clinical chemistry assays were performed to assess the progression of liver disease. MicroRNAs’ differential expression was evaluated on pooled RNAs from tissues, and some miRNAs showing dysregulation were further analyzed at the individual level.

Results

Cholesterol, low and high density lipoproteins, triglycerides and alanine aminotransferase increase was detected in HF mice. Gross anatomical examination revealed hepatomegaly in HF livers, and histological analysis highlighted different degrees and levels of steatosis, inflammatory infiltrate and fibrosis in HF and LF animals, demonstrating the progression from NAFLD through NASH. Macroscopic nodules, showing typical neoplastic features, were observed in 20 % of HF diet fed mice. Fifteen miRNAs differentially expressed in HF with respect to LF hepatic tissues during the progression of liver damage, and in tumors with respect to HF non tumor liver specimens were identified. Among them, miR-340-5p, miR-484, miR-574-3p, miR-720, whose expression was never described in NAFLD, NASH and HCC tissues, and miR-125a-5p and miR-182, which showed early and significant dysregulation in the sequential hepatic damage process.

Conclusions

In this study, fifteen microRNAs which were modulated in hepatic tissues and in tumors during the transition NAFLD-NASH-HCC are reported. Besides some already described, new and early dysregulated miRNAs were identified. Functional analyses are needed to validate the results here obtained, and to better define the role of these molecules in the progression of the hepatic disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-2007-1) contains supplementary material, which is available to authorized users.

Bioinformatics approach to predict target genes for dysregulated microRNAs in hepatocellular carcinoma: study on a chemically-induced HCC mouse model

Background

Hepatocellular carcinoma (HCC) is an aggressive epithelial tumor which shows very poor prognosis and high rate of recurrence, representing an urgent problem for public healthcare. MicroRNAs (miRNAs/miRs) are a class of small, non-coding RNAs that attract great attention because of their role in regulation of processes such as cellular growth, proliferation, apoptosis. Because of the thousands of potential interactions between a single miR and target mRNAs, bioinformatics prediction tools are very useful to facilitate the task for individuating and selecting putative target genes. In this study, we present a chemically-induced HCC mouse model to identify differential expression of miRNAs during the progression of the hepatic injury up to HCC onset. In addition, we describe an established bioinformatics approach to highlight putative target genes and protein interaction networks where they are involved.

Results

We describe four miRs (miR-125a-5p, miR-27a, miR-182, miR-193b) which showed to be differentially expressed in the chemically-induced HCC mouse model. The miRs were subjected to four of the most used predictions tools and 15 predicted target genes were identified. The expression of one (ANK3) among the 15 predicted targets was further validated by immunoblotting. Then, enrichment annotation analysis was performed revealing significant clusters, including some playing a role in ion transporter activity, regulation of receptor protein serine/threonine kinase signaling pathway, protein import into nucleus, regulation of intracellular protein transport, regulation of cell adhesion, growth factor binding, and regulation of TGF-beta/SMAD signaling pathway. A network construction was created and links between the selected miRs, the predicted targets as well as the possible interactions among them and other proteins were built up.

Conclusions

In this study, we combined miRNA expression analysis, obtained by an in vivo HCC mouse model, with a bioinformatics-based workflow. New genes, pathways and protein interactions, putatively involved in HCC initiation and progression, were identified and explored.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-015-0836-1) contains supplementary material, which is available to authorized users.

Serum MicroRNAs as Potential Biomarkers for Early Diagnosis of Hepatitis C Virus-Related Hepatocellular Carcinoma in Egyptian Patients

Circulating microRNAs are deregulated in liver fibrosis and hepatocellular carcinoma (HCC) and are candidate biomarkers. This study investigated the potential of serum microRNAs; miR-19a, miR-296, miR-130a, miR-195, miR-192, miR-34a, and miR-146a as early diagnostic biomarkers for hepatitis C virus (HCV)-related HCC. As how these microRNAs change during liver fibrosis progression is not clear, we explored their serum levels during fibrosis progression in HCV-associated chronic liver disease (CLD) and if they could serve as non-invasive biomarkers for fibrosis progression to HCC. 112 Egyptian HCV-HCC patients, 125 non-malignant HCV-CLD patients, and 42 healthy controls were included. CLD patients were subdivided according to Metavir fibrosis-scoring. Serum microRNAs were measured by qRT-PCR custom array. Serum microRNAs were deregulated in HCC versus controls, and except miR-130a, they were differentially expressed between HCC and CLD or late fibrosis (F3-F4) subgroup. Serum microRNAs were not significantly different between individual fibrosis-stages or between F1-F2 (early/moderate fibrosis) and F3-F4. Only miR-19a was significantly downregulated from liver fibrosis (F1-F3) to cirrhosis (F4) to HCC. Individual microRNAs discriminated HCC from controls, and except miR-130a, they distinguished HCC from CLD or F3-F4 patients by receiver-operating-characteristic analysis. Multivariate logistic analysis revealed a panel of four microRNAs (miR-19a, miR-195, miR-192, and miR-146a) with high diagnostic accuracy for HCC (AUC = 0.946). The microRNA panel also discriminated HCC from controls (AUC = 0.949), CLD (AUC = 0.945), and F3-F4 (AUC = 0.955). Studied microRNAs were positively correlated in HCC group. miR-19a and miR-34a were correlated with portal vein thrombosis and HCC staging scores, respectively. In conclusion, studied microRNAs, but not miR-130a, could serve as potential early biomarkers for HCC in high-risk groups, with miR-19a as a biomarker for liver fibrosis progression to cirrhosis to HCC. We identified a panel of four serum microRNAs with high accuracy in HCC diagnosis. Additional studies are required to confirm this panel and test its prognostic significance.

MicroRNA expression in hepatitis C virus-related malignancies: A brief review

Not only is chronic hepatitis C virus (HCV) infection a major public health problem, but also it can cause hepatocellular carcinoma and, more rarely, non-Hodgkin’s lymphoma. These characteristics mean that HCV is the only virus infecting humans that is able to cause two different cancers. The fine pathogenetic and molecular mechanisms by which HCV induces these two malignancies are not completely clear. In the last decade, it has been shown that microRNAs (miRNAs), a class of 21-23-nucleotide molecules modulating post-transcriptional gene expression, make an important contribution to the pathogenesis of several cancers and are also considered highly promising biomarkers. Here, we briefly describe the current knowledge about microRNAs’ involvement in HCV-related molecular oncogenesis. We decided to focus our attention on studies fully conducted on ex vivo samples with this specific etiology, and on cultured cell lines partially or completely expressing the HCV genome. Some of the results reported in this review are controversial, possibly because of methodological issues, differences in sampling size and features, and ethnicity of patients. What is certain is that miRNAs play a remarkable role in regulating gene expression during oncogenetic processes and in viral infection. A clear understanding of their effects is fundamental to elucidating the mechanisms underlying virus-induced malignancies.

Non-Coding RNAs in Primary Liver Cancer

Hepatocellular carcinoma (HCC) is a primary malignancy of the liver with poor prognosis and limited therapeutic options. Over the past few years, many studies have evaluated the role of non-coding RNAs (ncRNAs) in hepatocarcinogenesis and tumor progression. ncRNAs were shown to have diagnostic, prognostic, and therapeutic potential in HCC. In this manuscript, we review the latest major discoveries concerning microRNAs and long ncRNAs in HCC pathogenesis, and discuss the potentials and the limitations for their use in clinical practice.