Molecular alterations in hepatocellular carcinoma associated with hepatitis B and hepatitis C infections

Liver fibrosis pathologies and potentials of RNA based therapeutics modalities

Liver fibrosis (LF) occurs when the liver tissue responds to injury or inflammation by producing excessive amounts of scar tissue, known as the extracellular matrix. This buildup stiffens the liver tissue, hinders blood flow, and ultimately impairs liver function. Various factors can trigger this process, including bloodborne pathogens, genetic predisposition, alcohol abuse, non-steroidal anti-inflammatory drugs, non-alcoholic steatohepatitis, and non-alcoholic fatty liver disease. While some existing small-molecule therapies offer limited benefits, there is a pressing need for more effective treatments that can truly cure LF. RNA therapeutics have emerged as a promising approach, as they can potentially downregulate cytokine levels in cells responsible for liver fibrosis. Researchers are actively exploring various RNA-based therapeutics, such as mRNA, siRNA, miRNA, lncRNA, and oligonucleotides, to assess their efficacy in animal models. Furthermore, targeted drug delivery systems hold immense potential in this field. By utilizing lipid nanoparticles, exosomes, nanocomplexes, micelles, and polymeric nanoparticles, researchers aim to deliver therapeutic agents directly to specific biomarkers or cytokines within the fibrotic liver, increasing their effectiveness and reducing side effects. In conclusion, this review highlights the complex nature of liver fibrosis, its underlying causes, and the promising potential of RNA-based therapeutics and targeted delivery systems. Continued research in these areas could lead to the development of more effective and personalized treatment options for LF patients.

Liver Fibrosis: From Basic Science towards Clinical Progress, Focusing on the Central Role of Hepatic Stellate Cells

The burden of chronic liver disease is globally increasing at an alarming rate. Chronic liver injury leads to liver inflammation and fibrosis (LF) as critical determinants of long-term outcomes such as cirrhosis, liver cancer, and mortality. LF is a wound-healing process characterized by excessive deposition of extracellular matrix (ECM) proteins due to the activation of hepatic stellate cells (HSCs). In the healthy liver, quiescent HSCs metabolize and store retinoids. Upon fibrogenic activation, quiescent HSCs transdifferentiate into myofibroblasts; lose their vitamin A; upregulate α-smooth muscle actin; and produce proinflammatory soluble mediators, collagens, and inhibitors of ECM degradation. Activated HSCs are the main effector cells during hepatic fibrogenesis. In addition, the accumulation and activation of profibrogenic macrophages in response to hepatocyte death play a critical role in the initiation of HSC activation and survival. The main source of myofibroblasts is resident HSCs. Activated HSCs migrate to the site of active fibrogenesis to initiate the formation of a fibrous scar. Single-cell technologies revealed that quiescent HSCs are highly homogenous, while activated HSCs/myofibroblasts are much more heterogeneous. The complex process of inflammation results from the response of various hepatic cells to hepatocellular death and inflammatory signals related to intrahepatic injury pathways or extrahepatic mediators. Inflammatory processes modulate fibrogenesis by activating HSCs and, in turn, drive immune mechanisms via cytokines and chemokines. Increasing evidence also suggests that cellular stress responses contribute to fibrogenesis. Recent data demonstrated that LF can revert even at advanced stages of cirrhosis if the underlying cause is eliminated, which inhibits the inflammatory and profibrogenic cells. However, despite numerous clinical studies on plausible drug candidates, an approved antifibrotic therapy still remains elusive. This state-of-the-art review presents cellular and molecular mechanisms involved in hepatic fibrogenesis and its resolution, as well as comprehensively discusses the drivers linking liver injury to chronic liver inflammation and LF.

Molecular Mechanisms in Tumorigenesis of Hepatocellular Carcinoma and in Target Treatments-An Overview

Hepatocellular carcinoma is the most common primary malignancy of the liver, with hepatocellular differentiation. It is ranked sixth among the most common cancers worldwide and is the third leading cause of cancer-related deaths. The most important etiological factors discussed here are viral infection (HBV, HCV), exposure to aflatoxin B1, metabolic syndrome, and obesity (as an independent factor). Directly or indirectly, they induce chromosomal aberrations, mutations, and epigenetic changes in specific genes involved in intracellular signaling pathways, responsible for synthesis of growth factors, cell proliferation, differentiation, survival, the metastasis process (including the epithelial-mesenchymal transition and the expression of adhesion molecules), and angiogenesis. All these disrupted molecular mechanisms contribute to hepatocarcinogenesis. Furthermore, equally important is the interaction between tumor cells and the components of the tumor microenvironment: inflammatory cells and macrophages-predominantly with a pro-tumoral role-hepatic stellate cells, tumor-associated fibroblasts, cancer stem cells, extracellular vesicles, and the extracellular matrix. In this paper, we reviewed the molecular biology of hepatocellular carcinoma and the intricate mechanisms involved in hepatocarcinogenesis, and we highlighted how certain signaling pathways can be pharmacologically influenced at various levels with specific molecules. Additionally, we mentioned several examples of recent clinical trials and briefly described the current treatment protocol according to the NCCN guidelines.

Integrative Analysis of the Role of TP53 in Human Pan-Cancer

Tumor protein P53 (TP53) is an important tumor suppressor gene in humans. Under normal circumstances, TP53 can help repair mutated genes, or promote the death of cells with severe gene mutations (specifically, TP53 prevents cells from arrest in the G1/S phase when deoxyribonucleic acid (DNA) is damaged and promotes apoptosis if not repaired), and prevents normal cells from becoming malignant cells. TP53 mutations affect its tumor suppressor function, leading to the development of malignant tumors. In this study, using a public database, we explored the pan-cancer expression of TP53, its impact on patient survival and prognosis, the types of gene mutations, its correlation with immunity, and its regulation of other transcription factors and micro RNA (miRNA). The docking sites of therapeutic drugs and key amino acid sites of action provide a basis for future targeted therapies. TP53 has important biological functions in the human body. This study provides a theoretical basis for clinical TP53 gene therapy.

System Biology Investigation Revealed Lipopolysaccharide and Alcohol-Induced Hepatocellular Carcinoma Resembled Hepatitis B Virus Immunobiology and Pathogenesis

Hepatitis B infection caused by the hepatitis B virus is a life-threatening cause of liver fibrosis, cirrhosis, and hepatocellular carcinoma. Researchers have produced multiple in vivo models for hepatitis B virus (HBV) and, currently, there are no specific laboratory animal models available to study HBV pathogenesis or immune response; nonetheless, their limitations prevent them from being used to study HBV pathogenesis, immune response, or therapeutic methods because HBV can only infect humans and chimpanzees. The current study is the first of its kind to identify a suitable chemically induced liver cirrhosis/HCC model that parallels HBV pathophysiology. Initially, data from the peer-reviewed literature and the GeneCards database were compiled to identify the genes that HBV and seven drugs (acetaminophen, isoniazid, alcohol, D-galactosamine, lipopolysaccharide, thioacetamide, and rifampicin) regulate. Functional enrichment analysis was performed in the STRING server. The network HBV/Chemical, genes, and pathways were constructed by Cytoscape 3.6.1. About 1546 genes were modulated by HBV, of which 25.2% and 17.6% of the genes were common for alcohol and lipopolysaccharide-induced hepatitis. In accordance with the enrichment analysis, HBV activates the signaling pathways for apoptosis, cell cycle, PI3K-Akt, TNF, JAK-STAT, MAPK, chemokines, NF-kappa B, and TGF-beta. In addition, alcohol and lipopolysaccharide significantly activated these pathways more than other chemicals, with higher gene counts and lower FDR scores. In conclusion, alcohol-induced hepatitis could be a suitable model to study chronic HBV infection and lipopolysaccharide-induced hepatitis for an acute inflammatory response to HBV.

Liver fibrosis and MAFLD: the exploration of multi-drug combination therapy strategies

In recent years, the prevalence of metabolic-associated fatty liver disease (MAFLD) has reached pandemic proportions as a leading cause of liver fibrosis worldwide. However, the stage of liver fibrosis is associated with an increased risk of severe liver-related and cardiovascular events and is the strongest predictor of mortality in MAFLD patients. More and more people believe that MAFLD is a multifactorial disease with multiple pathways are involved in promoting the progression of liver fibrosis. Numerous drug targets and drugs have been explored for various anti-fibrosis pathways. The treatment of single medicines is brutal to obtain satisfactory results, so the strategies of multi-drug combination therapies have attracted increasing attention. In this review, we discuss the mechanism of MAFLD-related liver fibrosis and its regression, summarize the current intervention and treatment methods for this disease, and focus on the analysis of drug combination strategies for MAFLD and its subsequent liver fibrosis in recent years to explore safer and more effective multi-drug combination therapy strategies.

Protective Effects of Naringin-Dextrin Nanoformula against Chemically Induced Hepatocellular Carcinoma in Wistar Rats: Roles of Oxidative Stress, Inflammation, Cell Apoptosis, and Proliferation

Nanotechnology holds great promise for the development of treatments for deadly human diseases, such as hepatocellular carcinoma (HCC). In the current study, we compared the hepatoprotective effects of naringin-dextrin nanoparticles (NDNPs) against HCC in male Wistar rats with those of pure naringin and investigated the underlying cellular and molecular mechanisms. HCC was induced by intraperitoneal injection of diethylnitrosamine (DEN, 150 mg/kg body weight (b.w.) per week) for two weeks, followed by oral administration of 2-acetylaminofluorene (2AAF, 20 mg/kg b.w.) four times per week for three weeks. DEN/2AAF-administered rats were divided into three groups that respectively received 1% carboxymethyl cellulose (as vehicle), 10 mg/kg b.w. naringin, or 10 mg/kg b.w. NDNP every other day by oral gavage for 24 weeks. Both naringin and NDNP significantly attenuated the harmful effects of DEN on liver function. Both compounds also suppressed tumorigenesis as indicated by the reduced serum concentrations of liver tumor markers, and this antitumor effect was confirmed by histopathological evaluation. Additionally, naringin and NDNP prevented DEN-induced changes in hepatic oxidative stress and antioxidant activities. In addition, naringin and NDNP suppressed inflammation induced by DEN. Moreover, naringin and NDNP significantly reduced the hepatic expression of Bcl-2 and increased Bax, p53, and PDCD5 expressions. Naringin and NDNP also reduced expression of IQGAP1, IQGAP3, Ras signaling, and Ki-67 while increasing expression of IQGAP2. Notably, NDNP more effectively mitigated oxidative stress and inflammatory signaling than free naringin and demonstrated improved antitumor efficacy, suggesting that this nanoformulation improves bioavailability within nascent tumor sites.

Clinical Characteristics of TZAP (ZBTB48) in Hepatocellular Carcinomas from Tissue, Cell Line, and TCGA

Background and Objectives: ZBTB48 is a telomere-related protein that has been renamed telomeric zinc finger-associated protein (TZAP). It favorably binds to elongated telomeres to regulate their appropriate length. However, TZAP expression has not been investigated in hepatocellular carcinomas (HCC). Materials and Methods: The clinical significance of TZAP expression in 72 HCC was investigated. Additionally, its findings were supported by open big data and cancer cell lines. Results: TZAP expression level was not associated with the clinical parameters of HCC. TZAP expression induced a poorer survival result (overall survival, p = 0.020; disease-free survival, p = 0.012). TCGA data showed TZAP expression was more frequently found in HCCs with hepatitis C infection (p = 0.023). However, TCGA data revealed that TZAP expression did not predict HCC prognosis. In a cell line study, TZAP inhibition via siRNA suppressed PLC/PRF/5 cell growth; however, cell viability was increased in HepG2 cells. Conclusions: We presented the clinical and prognostic values of TZAP expression in HCC tissues and cancer cell lines. Additionally, the TCGA results also revealed a significant role for TZAP expression. TZAP expression may involve HCC progression and its prognosis.

MicroRNA 21as a novel biomarker in hepatitis C virus-related hepatocellular carcinoma

Background

Hepatocellular carcinoma is considered one of the most common cancers occurring in human population all over the world. It became an increasingly threatening malignancy due to both morbidity and mortality. Chronic viral hepatitis B and hepatitis C are two risk factors, which account for 80–90% of all HCC cases worldwide. Alfa Feto protien is used as a tumor marker for HCC diagnosis and prognosis prediction; however, its false negative rate when used alone is as high as 40% for patients with early-stage HCC. AFP levels remain normal in 15–30% of all the patients, even patients with advanced HCC. It has been demonstrated that miRNAs (MicroRNAs) are an important class of non-coding RNAs. They act as tumor oncogenes or suppressors and are involved in the HCC development. MiRNAs are endogenous nucleotides that can be found in intra- and extracellular spaces, such as the blood, urine, and saliva.

The study evaluated the miRNA 21 as a novel biomarker in patients with HCV related hepatocellular carcinoma.

Results

The study was conducted on three groups. Group (1) included 25 patients with liver cirrhosis due to hepatitis C virus infection. Group (2) included 25 patients with hepatocellular carcinoma (HCC) on top of liver cirrhosis due to hepatitis C virus infection. Group (3) included 10 normal control subjects. There was a significant difference in the mean level of miRNA between the three groups with p value < 0.001 with the highest value in group 2 ( 8.28 ± 2.55), then in group1 (5.04 ± 2.11) and the lowest in group 3 (control) (1.02 ± 0.07). MiRNA 21 has a sensitivity of 68% and a specificity of 96%, to differentiate between the liver cirrhosis group and HCC group.

Conclusion

miRNA 21 can be a promising marker for detection of patients with HCV-related hepatocellular carcinoma, with higher specificity compared to α feto protein; however, its cost is higher.

Custom gene expression panel for evaluation of potential molecular markers in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related mortality worldwide. It is a highly heterogeneous disease with poor prognosis and limited treatment options, which highlights the need for reliable biomarkers. This study aims to explore molecular markers that allow stratification of HCC and may lead to better prognosis and treatment prediction.

MATERIALS AND METHODS

We studied 20 candidate genes (HCC hub genes, potential drug target genes, predominant somatic mutant genes) retrieved from literature and public databases with potential to be used as the molecular markers. We analysed expression of the genes by RT-qPCR in 30 HCC tumour and adjacent non-tumour paired samples from Vietnamese patients. Fold changes in expression were then determined using the 2-∆∆CT method, and unsupervised hierarchical clustering was generated using Cluster v3.0 software.

RESULTS

Clustering of expression data revealed two subtypes of tumours (proliferative and normal-like) and four clusters for genes. The expression profiles of the genes TOP2A, CDK1, BIRC5, GPC3, IGF2, and AFP were strongly correlated. Proliferative tumours were characterized by high expression of the c-MET, ARID1A, CTNNB1, RAF1, LGR5, and GLUL1 genes. TOP2A, CDK1, and BIRC5 HCC hub genes were highly expressed (> twofold) in 90% (27/30), 83% (25/30), and 83% (24/30) in the tissue samples, respectively. Among the drug target genes, high expression was observed in the GPC3, IGF2 and c-MET genes in 77% (23/30), 63% (19/30), and 37% (11/30), respectively. The somatic mutant Wnt/ß-catenin genes (CTNNB1, GLUL and LGR5) and TERT were highly expressed in 40% and 33% of HCCs, respectively. Among the HCC marker genes, a higher percentage of tumours showed GPC3 expression compared to AFP expression [73% (23/30) vs. 43% (13/30)].

CONCLUSION

The custom panel and molecular markers from this study may be useful for diagnosis, prognosis, biomarker-guided clinical trial design, and prediction of treatment outcomes.

An overview of "Chronic viral infection and cancer, openings for vaccines" virtual symposium of the TechVac Network - December 16-17, 2021

This is a report on the research activities currently ongoing in virology, oncology and virus-associated cancers and possibilities of their treatment and prevention by vaccines and immunotherapies as outlined at the symposium “Chronic viral infection and cancer, openings for vaccines” virtually held on December 16–17, 2021. Experts from the various disciplines involved in the study of the complex relationships between solid tumors and viruses met to discuss recent developments in the field and to report their personal contributions to the specified topics. Secondary end point was to sustain the TECHVAC Network established in 2016 as a multidisciplinary work group specifically devoted to development of vaccines and immunotherapies against chronic viral infections and associated cancers, with the aim to identify areas of common interest, promote research cooperation, establish collaborative cross-border programs and projects, and to coordinate clinical and research activities.

A Narrative Review on LI-RADS Algorithm in Liver Tumors: Prospects and Pitfalls

Liver cancer is the sixth most detected tumor and the third leading cause of tumor death worldwide. Hepatocellular carcinoma (HCC) is the most common primary liver malignancy with specific risk factors and a targeted population. Imaging plays a major role in the management of HCC from screening to post-therapy follow-up. In order to optimize the diagnostic-therapeutic management and using a universal report, which allows more effective communication among the multidisciplinary team, several classification systems have been proposed over time, and LI-RADS is the most utilized. Currently, LI-RADS comprises four algorithms addressing screening and surveillance, diagnosis on computed tomography (CT)/magnetic resonance imaging (MRI), diagnosis on contrast-enhanced ultrasound (CEUS) and treatment response on CT/MRI. The algorithm allows guiding the radiologist through a stepwise process of assigning a category to a liver observation, recognizing both major and ancillary features. This process allows for characterizing liver lesions and assessing treatment. In this review, we highlighted both major and ancillary features that could define HCC. The distinctive dynamic vascular pattern of arterial hyperenhancement followed by washout in the portal-venous phase is the key hallmark of HCC, with a specificity value close to 100%. However, the sensitivity value of these combined criteria is inadequate. Recent evidence has proven that liver-specific contrast could be an important tool not only in increasing sensitivity but also in diagnosis as a major criterion. Although LI-RADS emerges as an essential instrument to support the management of liver tumors, still many improvements are needed to overcome the current limitations. In particular, features that may clearly distinguish HCC from cholangiocarcinoma (CCA) and combined HCC-CCA lesions and the assessment after locoregional radiation-based therapy are still fields of research.

All-trans retinoic acid inhibits HCV replication by downregulating core levels via E6AP-mediated proteasomal degradation

Here, we found that all-trans retinoic acid (ATRA), the most biologically active metabolite of vitamin A, strengthens the anti-viral defense mechanism of E6-associated protein (E6AP) that downregulates hepatitis C virus (HCV) Core levels via ubiquitin-dependent proteasomal degradation. For this effect, ATRA downregulated both protein and enzyme activity levels of DNA methyltransferase 1 and 3b and activated E6AP expression via promoter hypomethylation in HepG2 cells but not in Hep3B cells, in which p53 was absent. Ectopic p53 expression but not E6AP overexpression restored the ability of ATRA to downregulate HCV Core levels in Hep3B cells, suggesting a direct role of p53 in the E6AP-mediated ubiquitination of HCV Core. ATRA also downregulated HCV Core levels during HCV infection in Huh7D cells to inhibit virus replication, providing theoretical basis for the clinical application of ATRA against HCV infection.

Virus-Like Particles as Preventive and Therapeutic Cancer Vaccines

Virus-like particles (VLPs) are self-assembled viral protein complexes that mimic the native virus structure without being infectious. VLPs, similarly to wild type viruses, are able to efficiently target and activate dendritic cells (DCs) triggering the B and T cell immunities. Therefore, VLPs hold great promise for the development of effective and affordable vaccines in infectious diseases and cancers. Vaccine formulations based on VLPs, compared to other nanoparticles, have the advantage of incorporating multiple antigens derived from different proteins. Moreover, such antigens can be functionalized by chemical modifications without affecting the structural conformation or the antigenicity. This review summarizes the current status of preventive and therapeutic VLP-based vaccines developed against human oncoviruses as well as cancers.

Silybum marianum total extract, silymarin and silibinin abate hepatocarcinogenesis and hepatocellular carcinoma growth via modulation of the HGF/c-Met, Wnt/β-catenin, and PI3K/Akt/mTOR signaling pathways

Hepatocellular carcinoma (HCC) has been identified as one of the most deadly malignancies with limited therapeutic efficacy worldwide. However, understanding the molecular mechanisms of crosstalk between signaling pathways in HCC and predicting cancer cell responses to targeted therapeutic interventions remain to be challenge. Thus, in this study, we aimed to evaluate the anticancerous efficacy of Silybum marianum total extract (STE), silymarin (Sm), and silibinin (Sb) against experimentally-induced HCC in rats. In vitro investigations were also performed and the anticancer effects against HCC cell lines (HepG2 and Huh7) were confirmed. Wistar rats were given diethylnitrosamine (DEN)/2-acetylaminofluorene (AAF)/carbon tetrachloride (CCl4) and were orally treated with STE (200 mg/kg body weight (bw)), Sm (150 mg/kg bw), and Sb (5 mg/kg bw) every other day from the 1st or 16th week to the 25th week of DEN/AAF/CCl4 injection. Treatment with STE, Sm, and Sb inhibited the growth of cancerous lesions in DEN/AAF/CCl4-treated rats. This inhibition was associated with inhibition of Ki-67 expression and repression of HGF/cMet, Wnt/β-catenin, and PI3K/Akt/mTOR signaling pathways. STE, Sm, and Sb improved liver function biomarkers and tumor markers (AFP, CEA, and CA19.9) and increased total protein and albumin levels in serum. STE, Sm, and Sb treatment was also noted to reduce the hepatic production of lipid peroxides, increase hepatic glutathione content, and induce the activities of hepatic antioxidant enzymes in DEN/AAF/CCl4-treated rats. These results indicate that STE, Sm, and Sb exert anti-HCC effects through multiple pathways, including suppression of Ki-67 expression and HGF/cMet, Wnt/β-catenin, and PI3K/Akt/mTOR pathways and enhancement of antioxidant defense mechanisms.

Clinical Value for Diagnosis and Prognosis of Signal Sequence Receptor 1 (SSR1) and Its Potential Mechanism in Hepatocellular Carcinoma: A Comprehensive Study Based on High-Throughput Data Analysis

Objective

Hepatocellular Carcinoma (HCC) has the characteristics of high incidence and poor prognosis. However, the underlying mechanism of HCC has not yet been fully elucidated. This study aims to investigate the potential mechanism and clinical significance of signal sequence receptor (SSR1) in HCC through bioinformatics methods.

Methods

Four online (GEPIA, TIMER, TCGA, and GEO) databases were used to explore the expression level of SSR1 in HCC. The summary receiver operating characteristic (SROC) analysis and standardized mean difference (SMD) calculation were performed further to detect its diagnostic ability and expression level. The Human Protein Atlas (HPA) database was applied to verify the level of SSR1 protein expression. Chi-square test and Fisher’s exact test were carried out to determine the clinical relevance of SSR1 expression. KM survival analysis, univariate and multivariate COX regression analyses were employed to explore the prognostic impact of SSR1. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and Gene set enrichment analysis (GSEA) were implemented to reveal the underlying mechanism of SSR1. Quantitative Real-Time Polymerase Chain Reaction (QRT-PCR) was used to verify the expression of SSR1 in HCC.

Results

SSR1 was significantly overexpressed in HCC (SMD=1.25, P=0.03) and had the moderate diagnostic ability (AUC=0.84). SSR1 expression was significantly correlated with T stage, Gender, Pathologic stage (All P<0.05). Patients with high SSR1 expression had shorter overall survival (OS). Univariate and multivariate Cox regression analyses showed that high SSR1 expression was an independent risk factor for poor prognosis. KEGG analysis showed that SSR1-related genes were enriched in the cell cycle, DNA replication, and TGF-beta signaling pathway. GSEA analysis also shows that the high expression of SSR1 is related to the activation of the above three signal pathways. qRT-PCR showed that the SSR1 expression in HCC was significantly higher than the Peri-carcinoma tissue (PHCC) and the corresponding normal liver tissue.

Conclusion

SSR1 expression was significantly up-regulated, and it had the potential as a biomarker for the diagnosis and prognosis of HCC. It was very likely to participate in the occurrence and development of HCC by regulating the cell cycle. In summary, our study comprehensively analyzed the clinical value of SSR1 and also conducted a preliminary study on its potential mechanism, which will provide inspiration for the in-depth study of SSR1 in HCC.

Interleukin-17 in Liver Disease Pathogenesis

Interleukin 17A (IL-17A)-producing T helper 17 (Th17) cells were identified as a subset of T helper cells that play a critical role in host defense against bacterial and fungal pathogens. Th17 cells differentiate from Th0 naïve T-cells in response to transforming growth factor β1 (TGF-β1) and IL-6, the cytokines which also drive development of liver fibrosis, require activation of transcription factor retinoic acid receptor-related orphan nuclear receptor gamma t (RORγt). IL-17A signals through the ubiquitously expressed receptor IL-17RA. Expression of IL-17RA is upregulated in patients with hepatitis B virus/hepatitis C virus (HBV/HCV) infections, nonalcoholic steatohepatitis (NASH), alcohol-associated liver disease (AALD), hepatocellular carcinoma (HCC), and experimental models of chronic toxic liver injury. The role of IL-17 signaling in the pathogenesis of NASH- and AALD-induced metabolic liver injury and HCC will be the focus of this review. The role of IL-17A-IL-17RA axis in mediation of the cross-talk between metabolically injured hepatic macrophages, hepatocytes, and fibrogenic myofibroblasts will be discussed.

Identification and validation of viral antigens sharing sequence and structural homology with tumor-associated antigens (TAAs)

Background

The host’s immune system develops in equilibrium with both cellular self-antigens and non-self-antigens derived from microorganisms which enter the body during lifetime. In addition, during the years, a tumor may arise presenting to the immune system an additional pool of non-self-antigens, namely tumor antigens (tumor-associated antigens, TAAs; tumor-specific antigens, TSAs).

Methods

In the present study, we looked for homology between published TAAs and non-self-viral-derived epitopes. Bioinformatics analyses and ex vivo immunological validations have been performed.

Results

Surprisingly, several of such homologies have been found. Moreover, structural similarities between paired TAAs and viral peptides as well as comparable patterns of contact with HLA and T cell receptor (TCR) α and β chains have been observed. Therefore, the two classes of non-self-antigens (viral antigens and tumor antigens) may converge, eliciting cross-reacting CD8⁺ T cell responses which possibly drive the fate of cancer development and progression.

Conclusions

An established antiviral T cell memory may turn out to be an anticancer T cell memory, able to control the growth of a cancer developed during the lifetime if the expressed TAA is similar to the viral epitope. This may ultimately represent a relevant selective advantage for patients with cancer and may lead to a novel preventive anticancer vaccine strategy.

Roles of Toll-Like Receptor 3 in Human Tumors

Toll-like receptor 3 (TLR3) is an important member of the TLR family, which is an important group of pathogen-associated molecular patterns. TLR3 can recognize double-stranded RNA and induce activation of NF-κB and the production of type I interferons. In addition to its immune-associated role, TLR3 has also been detected in some tumors. However TLR3 can play protumor or antitumor roles in different tumors or cell lines. Here, we review the basic signaling associated with TLR3 and the pro- or antitumor roles of TLR3 in different types of tumors and discuss the possible reasons for the opposing roles of TLR3 in tumors.

Current status of ctDNA in precision oncology for hepatocellular carcinoma

The conventional method used to obtain a tumor biopsy for hepatocellular carcinoma (HCC) is invasive and does not evaluate dynamic cancer progression or assess tumor heterogeneity. It is thus imperative to create a novel non-invasive diagnostic technique for improvement in cancer screening, diagnosis, treatment selection, response assessment, and predicting prognosis for HCC. Circulating tumor DNA (ctDNA) is a non-invasive liquid biopsy method that reveals cancer-specific genetic and epigenetic aberrations. Owing to the development of technology in next-generation sequencing and PCR-based assays, the detection and quantification of ctDNA have greatly improved. In this publication, we provide an overview of current technologies used to detect ctDNA, the ctDNA markers utilized, and recent advances regarding the multiple clinical applications in the field of precision medicine for HCC.

Role of Mitochondria in Viral Infections

Viral diseases account for an increasing proportion of deaths worldwide. Viruses maneuver host cell machinery in an attempt to subvert the intracellular environment favorable for their replication. The mitochondrial network is highly susceptible to physiological and environmental insults, including viral infections. Viruses affect mitochondrial functions and impact mitochondrial metabolism, and innate immune signaling. Resurgence of host-virus interactions in recent literature emphasizes the key role of mitochondria and host metabolism on viral life processes. Mitochondrial dysfunction leads to damage of mitochondria that generate toxic compounds, importantly mitochondrial DNA, inducing systemic toxicity, leading to damage of multiple organs in the body. Mitochondrial dynamics and mitophagy are essential for the maintenance of mitochondrial quality control and homeostasis. Therefore, metabolic antagonists may be essential to gain a better understanding of viral diseases and develop effective antiviral therapeutics. This review briefly discusses how viruses exploit mitochondrial dynamics for virus proliferation and induce associated diseases.

Molecular and cellular mechanisms of liver fibrosis and its regression

Chronic liver injury leads to liver inflammation and fibrosis, through which activated myofibroblasts in the liver secrete extracellular matrix proteins that generate the fibrous scar. The primary source of these myofibroblasts are the resident hepatic stellate cells. Clinical and experimental liver fibrosis regresses when the causative agent is removed, which is associated with the elimination of these activated myofibroblasts and resorption of the fibrous scar. Understanding the mechanisms of liver fibrosis regression could identify new therapeutic targets to treat liver fibrosis. This Review summarizes studies of the molecular mechanisms underlying the reversibility of liver fibrosis, including apoptosis and the inactivation of hepatic stellate cells, the crosstalk between the liver and the systems that orchestrate the recruitment of bone marrow-derived macrophages (and other inflammatory cells) driving fibrosis resolution, and the interactions between various cell types that lead to the intracellular signalling that induces fibrosis or its regression. We also discuss strategies to target hepatic myofibroblasts (for example, via apoptosis or inactivation) and the myeloid cells that degrade the matrix (for example, via their recruitment to fibrotic liver) to facilitate fibrosis resolution and liver regeneration.

Hepatitis C virus core protein activates proteasomal activator 28 gamma to downregulate p16 levels via ubiquitin-independent proteasomal degradation

Proteasomal activator 28 gamma (PA28γ), an essential constituent of the 20S proteasome, is frequently overexpressed in hepatocellular carcinoma. Hepatitis C virus (HCV) core protein is recently known to activate PA28γ expression in human hepatocytes via upregulation of p53 levels; however, its role in HCV tumorigenesis remains unknown. Here, we found that HCV core-activated PA28γ downregulates p16 levels via ubiquitin-independent proteasomal degradation. As a result, HCV core protein activated the Rb-E2F pathway to stimulate cell cycle progression from G₁ to S phase, resulting in an increase in cell proliferation. The potential of HCV core protein to induce these effects was almost completely abolished by either PA28γ knockdown or p16 overexpression, confirming the role of the PA28γ-mediated p16 degradation in HCV tumorigenesis.

Gene and protein expression of mTOR and LC3 in hepatocellular carcinoma, colorectal liver metastasis and "normal" liver tissues

The physiological role of autophagy in the progression of liver diseases is still debated. To understand the clinical relevance of autophagy in primary e secondary hepatic tumors, we analyzed the expression of mTOR (mammalian target of rapamycin), a key regulator of autophagy; Raptor (regulatory-associated protein of mTOR); ULK1 (Unc-51 like kinase 1) determinant in the autophagy initiation; LC3 (microtubule-associated protein 1A/1B-light chain 3), a specific marker of autophagosomes; and p62, a selective autophagy receptor. Samples from subjects with chronic hepatitis (n.58), cirrhosis (n.12), hepatocellular carcinoma (HCC, n.56), metastases (n.48) from colorectal cancer and hyperplasia or gallbladder stones (n.7), the latter considered as controls, were examined. Gene expression analysis was carried out in n.213 tissues by absolute q-PCR, while protein expression by Western Blot in n.191 lysates, including tumoral, surrounding tumoral and normal tissues. Nonparametric statistical tests were used for comparing expression levels in the above-mentioned groups. Subgroup analysis was performed considering viral infection and chemotherapy treatment. The mTOR transcriptional level was significantly lower in metastases compared to HCC (P = 0.0001). p-mTOR(Ser2448) and LC3II/LC3I protein levels were significantly higher in metastases compared to HCC (P = 0.008 and P<0.0001, respectively). ULK(Ser757) levels were significantly higher in HCC compared to metastases (P = 0.0002) while the HCV- and HBV- related HCC showed the highest p62 levels. Chemotherapy induced a down-regulation of the p-mTOR(Ser2448) in metastases and in non-tumor surrounding tissues in treated patients compared to untreated (P = 0.001 and P = 0.005, respectively). Conclusions: the different expression of proteins considered, owning their interaction and diverse tissue microenvironment, indicate an impairment of the autophagy flux in primary liver tumors that is critical for the promotion of tumorigenesis process and a coexistence of autophagy inhibition and activation mechanisms in secondary liver tumors. Differences in mTOR and LC3 transcripts emerged in tumor-free tissues, therefore particular attention should be considered in selecting the control group.

lncRNA DLGAP1-AS2 Knockdown Inhibits Hepatocellular Carcinoma Cell Migration and Invasion by Regulating miR-154-5p Methylation

Objective

DLGAP1-AS2 has been characterized as an oncogenic lncRNA in glioma. Our preliminary microarray analysis revealed the altered expression of DLGAP1-AS2 in hepatocellular carcinoma (HCC), but the role of DLGAP1-AS2 in HCC remains unknown.

Method

Expression of DLGAP1-AS2 and miR-154-5p in paired HCC and nontumor tissues from 62 HCC patients was determined by RT-qPCR. The 62 HCC patients were followed up for 5 years to analyze the prognostic value of DLGAP1-AS2 for HCC. DLGAP1-AS2 knockdown and miR-154-5p overexpression was achieved in HCC cells to study the relationship between them. Methylation of miR-154-5p was analyzed by methylation-specific PCR. Cell proliferation was analyzed by CCK-8 assay.

Results

DLGAP1-AS2 was upregulated in HCC and predicted poor survival. miR-154-5p was downregulated in HCC and inversely correlated with DLGAP1-AS2. In HCC cells, DLGAP1-AS2 knockdown resulted in the upregulation of miR-154-5p expression and decreased methylation of miR-154-5p gene. Transwell assay showed that DLGAP1-AS2 knockdown and miR-154-5p overexpression inhibited cell invasion and migration, and the combination of LGAP1-AS2 knockdown and miR-154-5p overexpression showed stronger effects.

Conclusion

DLGAP1-AS2 knockdown may inhibit HCC cell migration and invasion by regulating miR-154-5p methylation.

Eradication of Hepatitis C Virus (HCV) Improves Survival of Hepatocellular Carcinoma Patients with Active HCV Infection - A Real-World Cohort Study

Background

Hepatocellular carcinoma (HCC) caused by hepatitis C virus (HCV) infection has become less and less due to the use of direct-acting antiviral agents (DAAs). Although it may be common to assume that eradication of the virus should improve the survival of HCC patients, large-scale randomized clinical data to support the correlation between viral load and prognosis are still lacking in China. The aim of the study was to evaluate the efficacy of antiviral therapy for HCC patients with active HCV infection.

Patients and Methods

We retrospectively enrolled 80 HCC patients with active HCV infection. Active HCV infection was defined as positive for HCV antibody with detectable HCV RNA by polymerase chain reaction.

Results

Forty-four patients (55.0%) received interferon combined with ribavirin treatment and 23 patients achieved sustained virological response (SVR). The 1-year survival rate in patients who achieved SVR was the highest, followed by those with non-SVR after antiviral treatment, and those without antiviral therapy (1-year survival rate were 91.3%, 88.4%, and 73.1%, respectively, P = 0.012). In the univariate analysis, alcohol intake and alpha-fetoprotein >20 ng/mL were associated with lower overall survival (OS) (P = 0.025 and P = 0.044, respectively), while SVR after antiviral treatment was associated with longer OS (P = 0.016). In the multivariate analysis, only SVR after antiviral treatment was significantly associated with OS (P = 0.014).

Conclusion

Our results ensured that the elimination of HCV substantially improved OS in HCC patients with active HCV infection, and the prognosis of those patients without antiviral therapy was poor.

Quantitative assessment of lncRNA H19 polymorphisms and cancer risk: a meta-analysis based on 48,166 subjects

Recently, numerous studies have been performed to detect the association between H19 polymorphisms and cancer susceptibility. However, their results were inconsistent and controversial. So, we carried out a meta-analysis aiming to define the association exactly. Eligible studies were collected using PubMed and Embase databases up to March 31, 2019. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the strength of association. Sensitivity analysis and publication bias were established to evaluate the robustness of our results. Totally, 60 studies involving 20763 cases and 27403 patients were analysed in our meta-analysis. Our results indicated that H19 rs217727 C > T polymorphism was significantly associated with increased cancer risk. In subgroup analysis, similarly increased risk could be found in gastrointestinal group for rs2839698 and protective effect was observed in rs2107425 polymorphism for cancer development in Caucasian population. Trial sequential analysis strengthened findings of our meta-analysis that cumulative evidence was adequate. In summary, our meta-analysis supported that H19 polymorphisms may be associated with cancer susceptibility.

Hepatocellular Carcinoma Mechanisms Associated with Chronic HCV Infection and the Impact of Direct-Acting Antiviral Treatment

Hepatitis C virus (HCV) infection is the major risk factor for liver cirrhosis and hepatocellular carcinoma (HCC). The mechanisms of HCC initiation, growth, and metastasis appear to be highly complex due to the decade-long interactions between the virus, immune system, and overlapping bystander effects of host metabolic liver disease. The lack of a readily accessible animal model system for HCV is a significant obstacle to understand the mechanisms of viral carcinogenesis. Traditionally, the primary prevention strategy of HCC has been to eliminate infection by antiviral therapy. The success of virus elimination by antiviral treatment is determined by the SVR when the HCV is no longer detectable in serum. Interferon-alpha (IFN-α) and its analogs, pegylated IFN-α (PEG-IFN-α) alone with ribavirin (RBV), have been the primary antiviral treatment of HCV for many years with a low cure rate. The cloning and sequencing of HCV have allowed the development of cell culture models, which accelerated antiviral drug discovery. It resulted in the selection of highly effective direct-acting antiviral (DAA)-based combination therapy that now offers incredible success in curing HCV infection in more than 95% of all patients, including those with cirrhosis. However, several emerging recent publications claim that patients who have liver cirrhosis at the time of DAAs treatment face the risk of HCC occurrence and recurrence after viral cure. This remains a substantial challenge while addressing the long-term benefit of antiviral medicine. The host-related mechanisms that drive the risk of HCC in the absence of the virus are unknown. This review describes the multifaceted mechanisms that create a tumorigenic environment during chronic HCV infection. In addition to the potential oncogenic programming that drives HCC after viral clearance by DAAs, the current status of a biomarker development for early prediction of cirrhosis regression and HCC detection post viral treatment is discussed. Since DAAs treatment does not provide full protection against reinfection or viral transmission to other individuals, the recent studies for a vaccine development are also reviewed.

Identification of miRNA-mRNA associations in hepatocellular carcinoma using hierarchical integrative model

Background

The established role miRNA-mRNA regulation of gene expression has in oncogenesis highlights the importance of integrating miRNA with downstream mRNA targets. These findings call for investigations aimed at identifying disease-associated miRNA-mRNA pairs. Hierarchical integrative models (HIM) offer the opportunity to uncover the relationships between disease and the levels of different molecules measured in multiple omic studies.

Methods

The HIM model we formulated for analysis of mRNA-seq and miRNA-seq data can be specified with two levels: (1) a mechanistic submodel relating mRNAs to miRNAs, and (2) a clinical submodel relating disease status to mRNA and miRNA, while accounting for the mechanistic relationships in the first level.

Results

mRNA-seq and miRNA-seq data were acquired by analysis of tumor and normal liver tissues from 30 patients with hepatocellular carcinoma (HCC). We analyzed the data using HIM and identified 157 significant miRNA-mRNA pairs in HCC. The majority of these molecules have already been independently identified as being either diagnostic, prognostic, or therapeutic biomarker candidates for HCC. These pairs appear to be involved in processes contributing to the pathogenesis of HCC involving inflammation, regulation of cell cycle, apoptosis, and metabolism. For further evaluation of our method, we analyzed miRNA-seq and mRNA-seq data from TCGA network. While some of the miRNA-mRNA pairs we identified by analyzing both our and TCGA data are previously reported in the literature and overlap in regulation and function, new pairs have been identified that may contribute to the discovery of novel targets.

Conclusion

The results strongly support the hypothesis that miRNAs are important regulators of mRNAs in HCC. Furthermore, these results emphasize the biological relevance of studying miRNA-mRNA pairs.

Stem Cell Therapy for Hepatocellular Carcinoma: Future Perspectives

Hepatocellular carcinoma (HCC) is one of the most common types of cancer and results in a high mortality rate worldwide. Unfortunately, most cases of HCC are diagnosed in an advanced stage, resulting in a poor prognosis and ineffective treatment. HCC is often resistant to both radiotherapy and chemotherapy, resulting in a high recurrence rate. Although the use of stem cells is evolving into a potentially effective approach for the treatment of cancer, few studies on stem cell therapy in HCC have been published. The administration of stem cells from bone marrow, adipose tissue, the amnion, and the umbilical cord to experimental animal models of HCC has not yielded consistent responses. However, it is possible to induce the apoptosis of cancer cells, repress angiogenesis, and cause tumor regression by administration of genetically modified stem cells. New alternative approaches to cancer therapy, such as the use of stem cell derivatives, exosomes or stem cell extracts, have been proposed. In this review, we highlight these experimental approaches for the use of stem cells as a vehicle for local drug delivery.

Influence of Interferon-free Direct-acting Antiviral Therapy on Primary Hepatocellular Carcinoma Recurrence: A Landmark Time Analysis and Time-dependent Extended Cox Proportional Hazards Model Analysis

Objective The influence of interferon (IFN)-free direct-acting antiviral (DAA) on hepatocellular carcinoma (HCC) recurrence remains unclear. Previous retrospective analyses revealed that the time interval between HCC curative treatment and IFN-free DAA induction is the critical factor affecting HCC recurrence. Thus, this study aimed to examine the influence of DAA therapy on HCC recurrence considering this interval. Methods Factors contributing to HCC recurrence were retrospectively analyzed using a landmark time analysis and time-dependent extended Cox proportional hazards model. Patients After screening 620 patients who were diagnosed with primary HCC from January 2001 to December 2016, 76 patients with early-stage (primary and solitary) disease who received curative treatment and were positive for serum hepatitis C virus RNA were included. Results HCC recurrence was observed in 8 of 17 (47.1%) patients who had received IFN-free DAA therapy and 45 of 59 (76.3%) who had not. No significant difference was seen between the IFN-free DAA (-) and IFN-free DAA (+) groups in the landmark time and time-dependent Cox proportional hazards model analyses. However, IFN-free DAA therapy tended to decrease the HCC recurrence rate after curative treatment for primary HCC in patients with chronic hepatitis. In addition, IFN-free DAA therapy tended to decrease the second HCC recurrence rate after treatment for the first HCC recurrence. Conclusion Our results, with a consideration of the time interval between HCC curative treatment and IFN-free DAA induction, showed that IFN-free DAA therapy was not associated with early-stage HCC recurrence after curative treatment.

MTF2 Induces Epithelial-Mesenchymal Transition and Progression of Hepatocellular Carcinoma by Transcriptionally Activating Snail

Background

Metal regulatory transcription factor 2 (MTF2) has been previously reported as a protein binding to the metal response element of the mouse metallothionein promoter, which is involved in chromosome inactivation and pluripotency. However, the function of MTF2 in tumor formation and progression has not yet been completely elucidated.

Methods

The expression of MTF2 and clinicopathological characteristics were evaluated by hepatocellular carcinoma (HCC) tissue microarray of 240 specimens. The role of MTF2 on HCC progression was determined using MTT, crystal violet, and transwell assays. Tumor growth was monitored in a xenograft model, and intrahepatic metastasis models were established.

Results

The expression of MTF2 was increased in HCC and strongly associated with the clinical characteristics and prognosis. Forced expression of MTF2 in HCC cells significantly promoted cell growth, migration, and invasion in vitro. In contrast, downregulation of MTF2 inhibited cell growth, migration, and invasion in vitro. Moreover, knock down of MTF2 suppressed tumorigenesis and intrahepatic metastasis of HCC cells in vivo. Mechanistically, MTF2 overexpression may promote growth and epithelial-mesenchymal transition processes of HCC cells by facilitating Snail transcription.

Conclusion

MTF2 promotes the proliferation, migration, and invasion of HCC cells by regulating Snail transcription, providing a potential therapeutic candidate for patients with HCC.

Circulating tumor DNA/circulating tumor cells and the applicability in different causes induced hepatocellular carcinoma

In 2015, liquid biopsy was rated one of the top 10 breakthrough technologies of the year by MIT Technology Review. Liquid biopsy is a type of in vitro diagnostic method involving a noninvasive blood test. It is also a breakthrough technology used to detect tumors and cancers and assist in therapeutic strategies. The most widely used markers are circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA). Primary carcinoma of the liver is a malignancy of hepatocytes or intrahepatic biliary epithelial cells. The most common type of liver cancer is hepatocellular carcinoma (HCC), the causes of which mainly include infection with hepatitis B virus (HBV) and/or hepatitis C virus (HCV), alcohol abuse, aflatoxicosis, and nonalcoholic fatty liver disease/ nonalcoholic steatohepatitis. As there are few typical clinical characteristics during the early stage of the disease, early diagnosis of HCC is very challenging. However, CTCs and ctDNA carry tumor-specific information. Therefore, the detection and analysis of CTCs and ctDNA can provide evidence for the early diagnosis of HCC and guide treatment. Furthermore, several studies have indicated that different inducers of HCC cause different DNA mutations, and accordingly, detection of specific mutations in ctDNA will facilitate the determination of the HCC type and help physicians provide distinctive therapies.

Sweroside ameliorated carbon tetrachloride (CCl4)-induced liver fibrosis through FXR-miR-29a signaling pathway

To date, there are very few effective drugs for liver fibrosis treatment; therefore, it is urgent to develop novel therapeutic targets and approaches. In the present research, we sought to study the protective effect of sweroside contained in Lonicera japonica or blue honeysuckle berries in a mouse model of liver fibrosis and investigate the underlying mechanism. The mouse model of liver fibrosis in was induced by intraperitoneal injections of 10% CCl₄ for 6 weeks (three times/week). At the beginning of the fourth week, sweroside was intragastrically administered once a day and at the end of the treatment, biochemical and histological studies were investigated. The expression of FXR, miR-29a and the downstream targets were analyzed as well. Moreover, the effect of sweroside on cell proliferation was observed in human hepatic stellate cells (HSCs) (LX-2), along with using the siRNA for FXR and miR-29a inhibitor to investigate the underpinning of the anti-fibrotic effect of sweroside. Sweroside successfully protected the liver fibrosis in CCl₄-induced mouse model, accompanied by miR-29a induction. Furthermore, sweroside also induced miR-29a in HSCs, resulting in the inhibition of COL1 and TIMP1. Our data also showed that either silencing miR-29a or knockdown of FXR in LX-2 cell abolished the inhibition of COL1 and TIMP1 as well as the inhibition of cell proliferation by sweroside treatment. In conclusion, sweroside exerted its anti-fibrotic effect in vivo and in vitro by up-regulation of miR-29a and repression of COL1 and TIMP1, which was at least in part through FXR.

Diffuse and canalicular patterns of glypican-3 expression reflect malignancy of hepatocellular carcinoma

Glypican-3 (GPC3) is expressed in most hepatocellular carcinomas (HCCs). To investigate the significance of various GPC3 staining patterns in HCC, we classified 134 HCC patients into three groups: those with diffuse GPC3 staining, canalicular GPC3 staining, and others (including negative staining). HCCs with diffuse staining were correlated with poor differentiation, high Ki-67 indices, high serum α-fetoprotein (AFP) levels, and early recurrence. In contrast, HCCs with canalicular staining were well differentiated with lower AFP levels. Overall survival in this group was better than that of the other two groups. Comparative analysis of GPC3 staining patterns with markers for HCC subclassification showed that diffuse staining was correlated with the expression of biliary/stem cell markers, whereas canalicular staining was correlated with expression of the markers of WNT-activated HCCs. Induction of leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), known as a target of the WNT signaling pathway, in HCC cells resulted in reduced GPC3 expression in vitro. The LGR5-induced cells formed tumors with canaliculus-like structures in mice and showed canalicular GPC3 staining. The current findings showed the significance of recognizing distinct GPC3 staining patterns, i.e., diffuse and canalicular, which may reflect different carcinogenetic mechanisms and indicate the level of malignancy of HCC.

Molecular Mechanisms of Hepatocarcinogenesis Following Sustained Virological Response in Patients with Chronic Hepatitis C Virus Infection

Despite the success of direct-acting antiviral (DAA) agents in treating chronic hepatitis C virus (HCV) infection, the number of cases of HCV-related hepatocellular carcinoma (HCC) is expected to increase over the next five years. HCC develops over the span of decades and is closely associated with fibrosis stage. HCV both directly and indirectly establishes a pro-inflammatory environment favorable for viral replication. Repeated cycles of cell death and regeneration lead to genomic instability and loss of cell cycle control. DAA therapy offers >90% sustained virological response (SVR) rates with fewer side effects and restrictions than interferon. While elimination of HCV helps to restore liver function and reverse mild fibrosis, post-SVR patients remain at elevated risk of HCC. A series of studies reporting higher than expected rates of HCC development among DAA-treated patients ignited debate over whether use of DAAs elevates HCC risk compared to interferon. However, recent prospective and retrospective studies based on larger patient cohorts have found no significant difference in risk between DAA and interferon therapy once other factors are taken into account. Although many mechanisms and pathways involved in hepatocarcinogenesis have been elucidated, our understanding of drivers specific to post-SVR hepatocarcinogenesis is still limited, and lack of suitable in vivo and in vitro experimental systems has hampered efforts to examine etiology-specific mechanisms that might serve to answer this question more thoroughly. Further research is needed to identify risk factors and biomarkers for post-SVR HCC and to develop targeted therapies based on more complete understanding of the molecules and pathways implicated in hepatocarcinogenesis.

IL-6/STAT3 pathway intermediates M1/M2 macrophage polarization during the development of hepatocellular carcinoma

Human cancers, including hepatocellular carcinoma (HCC), are characterized by a high degree of drug resistance in chemotherapy. However, the underlying molecular mechanism remains unknown. To the role of interleukin-6 (IL-6)/signal transducer and activator of transcription 3 (STAT3) signaling pathway in the regulation of macrophage polarization, M1-type and M2-type macrophages were separately induced using lipopolysaccharide and interleukin-4 (IL-4), and we found that the IL-6/STAT3 signaling pathway was inhibited in M1-type macrophages but activated in M2-type macrophages. After anti-IL-6-treated macrophages were separately induced by lipopolysaccharide and IL-4, we found that the inhibition of IL-6/STAT3 signaling pathway turned macrophages into M1-type. Co-culture with M1-type macrophages reduced HCC cell viability, proliferation, invasion, migration, drug resistance, but increased apoptosis. Co-culture with M2-type macrophages yielded reciprocal results. The inhibition of IL-6/STAT3 signaling pathway mediated by anti-IL6 was shown to significantly enhance the effects of M1-type macrophages on HCC cells and rescue HCC cells from co-culture with M2-type macrophages. Tumor xenografts of co-cultured HCC cells were established in nude mice and the results showed that the inhibition of IL-6/STAT3 signaling pathway mediated by anti-IL6 was found to reduce tumor formation of HCC cells co-cultured with M1- or M2-type macrophages and lung metastases. The current study reveals a novel mechanism of IL-6/STAT3 signaling pathway in the regulation of macrophage polarization, thus contributing to HCC metastasis and drug resistance in chemotherapy.

Phase II Studies with Refametinib or Refametinib plus Sorafenib in Patients with RAS-Mutated Hepatocellular Carcinoma

Purpose: Refametinib, an oral MEK inhibitor, has demonstrated antitumor activity in combination with sorafenib in patients with RAS-mutated hepatocellular carcinoma (HCC). Two phase II studies evaluated the efficacy of refametinib monotherapy and refametinib plus sorafenib in patients with RAS-mutant unresectable or metastatic HCC.Patients and Methods: Eligible patients with RAS mutations of cell-free circulating tumor DNA (ctDNA) determined by beads, emulsion, amplification, and magnetics technology received twice-daily refametinib 50 mg ± sorafenib 400 mg. Potential biomarkers were assessed in ctDNA via next-generation sequencing (NGS).Results: Of 1,318 patients screened, 59 (4.4%) had a RAS mutation, of whom 16 received refametinib and 16 received refametinib plus sorafenib. With refametinib monotherapy, the objective response rate (ORR) was 0%, the disease control rate (DCR) was 56.3%, overall survival (OS) was 5.8 months, and progression-free survival (PFS) was 1.9 months. With refametinib plus sorafenib, the ORR was 6.3%, the DCR was 43.8%, OS was 12.7 months, and PFS was 1.5 months. In both studies, time to progression was 2.8 months. Treatment-emergent toxicities included fatigue, hypertension, and acneiform rash. Twenty-seven patients had ctDNA samples available for NGS. The most frequently detected mutations were in TERT (63.0%), TP53 (48.1%), and β-catenin (CTNNB1; 37.0%).Conclusions: Prospective testing for RAS family mutations using ctDNA was a feasible, noninvasive approach for large-scale mutational testing in patients with HCC. A median OS of 12.7 months with refametinib plus sorafenib in this small population of RAS-mutant patients may indicate a synergistic effect between sorafenib and refametinib-this preliminary finding should be further explored. Clin Cancer Res; 24(19); 4650-61. ©2018 AACR.

Ancient cancers and infection-induced oncogenesis

Cancers have been reported in bone and soft tissue of ancient agricultural populations. Fossilized bones from prehistoric periods provide evidence of tumors but only one example of cancer. Difficulties in diagnosing the causes of lesions in mummified tissue and fossilized bone, and in interpreting the prevalence of cancers from remains, draw attention to the need for complementary approaches to assess the occurrence of cancer in ancient populations. This paper integrates current knowledge about pathogen induction of cancer with phylogenetic analyses of oncogenic pathogens, and concludes that pathogen-induced cancers were probably generally present in ancient historic and prehistoric human populations. Consideration of cancers in extant human populations and wildlife lends credence to this conclusion, with the caveat that the presence of cancers may depend on population-specific exposures to oncogenic parasites and carcinogens.

Significant association between lncRNA H19 polymorphisms and cancer susceptibility: a meta-analysis

Previous epidemiological research suggests polymorphisms in long non-coding RNA (lncRNA) H19 are associated with an increased risk of cancer, but the results are inconsistent. We therefore conducted a meta-analysis to more accurately determine the association between lncRNA H19 polymorphisms and cancer risk. The PubMed, Embase, and Science Citation Index online databases were searched and 11 relevant studies involving a total of 33,209 participants were identified. Odds ratios (ORs) and corresponding 95% confidence interval (CIs) from these studies were used to detect associations between H19 polymorphisms and cancer risk using five genetic models. The pooled result suggested that the rs2839698 G>A polymorphism was associated with digestive cancer risk in all five models. Moreover, a protective effect against cancer development was observed for the T allele variant of the rs2107425 C>T polymorphism, especially in Caucasian patient populations. No significant associations were found between lncRNA H19 rs217727 G>A polymorphism and cancer risk. In summary, the rs2839698 G>A and rs2107425 C>T polymorphisms in lncRNA H19 may therefore play opposing roles during cancer development, and their effects may vary depending on cancer type and patient ethnicity.

Hepatitis C Virus-Associated Cancers

Most hepatitis C virus (HCV) infection results in persistent infection. Significant portion of chronic HCV-infected patients develop hepatocellular carcinoma (HCC). Chronic hepatitis C is also associated with extrahepatic manifestations, including cryoglobulinemia, lymphoma, insulin resistance, type 2 diabetes, and neurological disorders. The molecular mechanisms of how HCV infection causes liver cancer are largely unknown. HCV replication or viral proteins may perturb cellular hemostasis and induce the generation of reactive oxygen species (ROS); viral components or viral replication products act as agonist to trigger innate immune response and cause chronic inflammation. Within the liver, non-hepatocytes such as hepatic stellate cell (HSC) are activated upon HCV infection to provide the major source of extracellular proteins and play important roles in fibrogenesis. With the great achievements of HCV treatment, especially the direct-acting antivirals (DAAs) against HCV, HCV eradication is possible. However, until now there are only very limited data on the effect of DAA-based anti-HCV treatment on HCC patients.

The Role of Circulating Free DNA and MicroRNA in Non-Invasive Diagnosis of HBV- and HCV-Related Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the third and the fifth leading cause of cancer related death worldwide in men and in women, respectively. HCC generally has a poor prognosis, with a very low 5-year overall survival, due to delayed diagnosis and treatment. Early tumour detection and timely intervention are the best strategies to reduce morbidity and mortality in HCC patients. Histological evaluation of liver biopsies is the gold standard for cancer diagnosis, although it is an invasive, time-consuming and expensive procedure. Recently, the analysis of circulating free DNA (cfDNA) and RNA molecules released by tumour cells in body fluids, such as blood serum, saliva and urine, has attracted great interest for development of diagnostic assays based on circulating liver cancer molecular biomarkers. Such "liquid biopsies" have shown to be useful for the identification of specific molecular signatures in nucleic acids released by cancer cells, such as gene mutations and altered methylation of DNA as well as variations in the levels of circulating microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). Body fluids analysis may represent a valuable strategy to monitor liver disease progression in subjects chronically infected with hepatitis viruses or cancer relapse in HCC treated patients. Several studies showed that qualitative and quantitative assays evaluating molecular profiles of circulating cell-free nucleic acids could be successfully employed for early diagnosis and therapeutic management of HCC patients. This review describes the state of art on the use of liquid biopsy for cancer driver gene mutations, deregulated DNA methylation as well as miRNA levels in HCC diagnosis.

Tumor specific mutations in TERT promoter and CTNNB1 gene in hepatitis B and hepatitis C related hepatocellular carcinoma

Recurrent somatic mutations in the promoter region of telomerase reverse transcriptase (TERT) gene and in the exon 3 of CTNNB1 gene have been recognized as common events in hepatocellular carcinoma (HCC) with variable frequencies depending on etiology and geographical region. We have analyzed TERT promoter and CTNNB1 gene mutations in 122 cases of hepatitis B (HBV) and hepatitis C (HCV) related HCCs, in 7 cases of cholangiocarcinoma (CC) and hepatocholangiocarcinoma (HCC-CC) as well as in autologous cirrhotic tissues. Overall, 50.4% and 26% of HCC as well as 14.3% and none of CC and HCC-CC were mutated in TERT promoter and in CTNNB1 exon 3, respectively. TERT and CTNNB1 mutations were found more frequently in HCV related (53.6% and 26.4%, respectively) than HBV related (41.7% and 16.7%, respectively) HCCs and coexisted in 57.6% of CTNNB1 mutated tumors. Mutations in TERT and CTNNB1 were not associated with the functional promoter polymorphism rs2853669. No mutations were detected in the 129 non-HCC cirrhotic tissues. In conclusion, mutations in TERT promoter and in CTNNB1 gene represent specific cancer signatures in the pathogenesis of viral related HCC and could be promising early biomarkers as well as targets for tailored therapies.

The TERT promoter mutation incidence is modified by germline TERT rs2736098 and rs2736100 polymorphisms in hepatocellular carcinoma

Telomerase activation via induction of the catalytic component telomerase reverse transcriptase (TERT) plays essential roles in malignant transformation. TERT promoter-activating mutations were recently identified as a novel mechanism to activate telomerase in hepatocellular carcinoma (HCC) and many other malignancies. In addition, single nucleotide polymorphisms (SNPs) in the TERT rs2736098 and rs2736100 are significantly associated with cancer susceptibility. It is currently unclear whether different germline TERT variants modify TERT promoter mutations. Here we analyzed the TERT promoter status and genotyped the TERT SNPs at rs2736098 and rs2736100 in patients with HCC. Thirty percent of HCCs harbored TERT promoter mutations and there was a significant difference in rs2736098 and rs2736100 genotypes between wt and mutant TERT promoter-bearing HCC tumors (P = 0.007 and 0.018, respectively). For rs2736100, the cancer risk genotype CC was significantly associated with a reduced incidence of TERT promoter mutations compared to AA + AC variants [Odds ratio (OR): 0.181, 95% Confidence interval (CI): 0.0543-0.601, P = 0.004]. The rs2736098_CT genotype was significantly associated with the TERT promoter mutation-positive tumors compared to the TT genotype (OR: 5.391, 95% CI: 1.234-23.553, P = 0.025). These differences in genotype distribution did not differ between patients with a wt TERT promoter and controls. The presence of TERT promoter mutations was not associated with clinico-pathological variables. Taken together, the germline TERT genetic background may significantly affect the onset of TERT promoter mutations in HCCs, which provides a better understanding of HCC-related TERT promoter mutations and telomerase regulation in cancer.

MicroRNA-493-5p promotes apoptosis and suppresses proliferation and invasion in liver cancer cells by targeting VAMP2

The aim of the present study was to explore the role of miR‑493-5p in liver cancer tissues and cell lines, and its effect on cell behavioral characteristics. The expression of miR-493-5p was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) in liver cancer tissues and cell lines (hepatic cell line HL-7702 and the liver cancer cell lines HCCC-9810, HuH-7 and HepG2). In addition, the mechanism by which miR-493-5p mediates its effects was analyzed via the transfection of miR-493-5p mimic and negative control miRNA into HepG2 cells. The viability, proliferation, apoptosis and invasion of the cells were analyzed using MTT assay, flow cytometry and Transwell chamber experiments. Furthermore, the effect of miR-493-5p on the expression of vesicle associated membrane protein 2 (VAMP2) was assayed using a dual-luciferase reporter system, and VAMP2 protein levels were determined by western blot analysis. In addition, following the cotransfection of HepG2 cells with pcDNA3.1‑VAMP2 plasmid and miR‑493-5p mimic, the role of miR-493-5p as a regulator of VAMP2 was evaluated using MTT assay, flow cytometry and Transwell chamber experiments. RT-qPCR analysis indicated that the expression of miR-493-5p in liver cancer tissues and cell lines was decreased significantly compared with that in adjacent normal liver tissues and normal liver cell lines, respectively. Compared with the control group, the cells transfected with miR-493-5p mimic (the miR-493-5p overexpression group) exhibited reduced cell viability, a reduced percentage of cells in the S phase and an increased percentage of apoptotic cells. In addition, fewer cells passed through the Transwell membrane in the miR-493-5p overexpression group compared with the control group. In the dual-luciferase reporter assay, luciferase activity in the miR‑493-5p overexpression group was attenuated compared with that in the control group. In addition, western blot analysis indicated that the VAMP2 protein levels in the miR‑493-5p overexpression group were lower than those in the control group. Furthermore, in cells overexpressing miR-493-5p and VAMP2 simultaneously, the biological behavior of the cells, including cell viability, cell cycle and cell invasiveness, was significantly rescued compared with that of the control group transfected with miR‑493-5p alone. In conclusion, miR-493-5p is indicated to be a tumor suppressor gene, and is downregulated in human liver cancer. miR-493-5p overexpression promotes cell apoptosis and inhibits the proliferation and migration of liver cancer cells by negatively regulating the expression of VAMP. These observations suggest the potential of treating liver cancer by the overexpression of microRNA-493-5p.

Molecular basis of hepatocellular carcinoma induced by hepatitis C virus infection

Present study outlines a comprehensive view of published information about the underlying mechanisms operational for progression of chronic hepatitis C virus (HCV) infection to development of hepatocellular carcinoma (HCC). These reports are based on the results of animal experiments and human based studies. Although, the exact delineated mechanism is not yet established, there are evidences available to emphasize the involvement of HCV induced chronic inflammation, oxidative stress, insulin resistance, endoplasmic reticulum stress, hepato steatosis and liver fibrosis in the progression of HCV chronic disease to HCC. Persistent infection with replicating HCV not only initiates several liver alterations but also creates an environment for development of liver cancer. Various studies have reported that HCV acts both directly as well as indirectly in promoting this process. Whereas HCV related proteins, like HCV core, E1, E2, NS3 and NS5A, modulate signal pathways dysregulating cell cycle and cell metabolism, the chronic infection produces similar changes in an indirect way. HCV is an RNA virus and does not integrate with host genome and therefore, HCV induced hepatocarcinogenesis pursues a totally different mechanism causing imbalance between suppressors and proto-oncogenes and genomic integrity. However, the exact mechanism of HCC inducement still needs a full understanding of various steps involved in this process.

Hepatitis C virus Core overcomes all-trans retinoic acid-induced apoptosis in human hepatoma cells by inhibiting p14 expression via DNA methylation

All-trans retinoic acid (ATRA), the most biologically active metabolite of vitamin A, is known to induce p14 expression via promoter hypomethylation to activate the p14-MDM2-p53 pathway, which leads to activation of the p53-dependent apoptotic pathway and subsequent induction of apoptosis in human hepatoma cells. In the present study, we found that hepatitis C virus (HCV) Core derived from ectopic expression or HCV infection overcomes ATRA-induced apoptosis in p53-positive hepatoma cells. For this effect, HCV Core upregulated both protein levels and enzyme activities of DNA methyltransferase 1 (DNMT1), DNMT3a, and DNMT3b and thereby repressed p14 expression via promoter hypermethylation, resulting in inactivation of the pathway leading to p53 accumulation in the presence of ATRA. As a result, HCV Core prevented ATRA from activating several apoptosis-related molecules, including Bax, p53 upregulated modulator of apoptosis, caspase-9, caspase-3, and poly (ADP-ribose) polymerase. In addition, complementation of p14 in the Core-expressing cells by either ectopic expression or treatment with 5-Aza-2′dC almost completely abolished the potential of HCV Core to suppress ATRA-induced apoptosis. Based on these observations, we conclude that HCV Core executes its oncogenic potential by suppressing the p53-dependent apoptosis induced by ATRA in human hepatoma cells.

miRNA-346 promotes proliferation, migration and invasion in liver cancer

Liver cancer primarily accounts for the majority of malignancies of the liver. MicroRNAs (miRNAs) are endogenous non-coding RNAs, which are important in tumorigenesis. Abnormal expression of microRNA-346 (miR-346) has been demonstrated in various types of human cancer, however, its expression and potential molecular mechanism in liver cancer remains to be elucidated. Expression levels of miR-346 in liver cancer cell lines were determined by quantitative polymerase chain reaction. The effect of miR-346 on proliferation was evaluated by an MTT assay; cell migration and invasion were evaluated by Transwell migration and invasion assays and target protein expression was determined by western blotting. The present study observed that miR-346 was upregulated in liver cancer cell lines. miR-346 overexpression promoted cell proliferation, migration and invasion in liver cancer cells and conversely, inhibition of miR-346 resulted in the opposite effects. Furthermore, F-Box and leucine rich repeat protein (FBXL)2 was identified as a direct target of miR-346. miR-346 promoted proliferation, migration and invasion of liver cancer via FBXL2. Overall, these findings demonstrated that miR-346 may act as a potential prognostic marker and therapeutic target against liver cancer in the future.

Changes in renal function indices in cirrhotic chronic hepatitis C patients treated with sofosbuvir-containing regimens

This study aimed to explore changes in hepatic and renal function indices in chronic hepatitis C (CHC) patients treated with direct-acting antivirals (DAAs). Forty-three CHC patients treated with sofosbuvir (SOF)-containing regimens were enrolled. At the end of treatment, the estimated glomerular filtration rate (eGFR) level was significantly decreased and the serum creatinine (Scr) and uric acid (UA) levels were significantly increased compared with baseline levels (eGFR: 86.7 ± 20.4 vs 80.5 ± 21.3, P₀₁ = 0.005; Scr: 83.9 ± 19.1 vs 89.6 ± 21.1, P₀₁ < 0.001; UA: 323.7± 86.2 vs 358.5 ± 93.2, P₀₁ < 0.001); no significant improvements were observed at 24 w post-treatment (eGFR: 86.7 ± 20.4 vs 81.4 ± 18.6, P₀₂ = 0.013; Scr: 83.6 ± 17.9 vs 87.9 ± 18.3, P₀₂ = 0.014; UA: 320.8 ± 76.3 vs 349.3 ± 91.0, P₀₂ = 0.004). When the patients were grouped by liver conditions, non-cirrhotic patients and cirrhotic patients had decreased eGFR levels and increased Scr levels at the end of treatment; at 24 w post-treatment, the eGFR and Scr levels were significantly improved in non-cirrhotic patients (88.4 ± 21.7 vs 83.8 ± 18.5, P₀₂ = 0.142; 84.4 ± 20.4 vs 87.0 ± 16.9, P₀₂ = 0.088), while no obvious improvements were observed in cirrhotic patients (84.3 ± 18.7 vs 78.1 ± 18.6, P₀₂ = 0.002; 83.2 ± 17.7 vs 89.2 ± 20.6, P₀₂ = 0.006). Clinical physicians should closely monitor renal function in patients treated with SOF-containing regimens, especially in cirrhotic patients.