Hepatitis B Virus-Encoded HBsAg Contributes to Hepatocarcinogenesis by Inducing the Oncogenic Long Noncoding RNA LINC00665 through the NF-κB Pathway

Dopamine Inhibits the Expression of Hepatitis B Virus Surface and e Antigens by Activating the JAK/STAT Pathway and Upregulating Interferon-stimulated Gene 15 Expression

Background and Aims

Hepatitis B virus (HBV) infection is a major risk factor for cirrhosis and liver cancer, and its treatment continues to be difficult. We previously demonstrated that a dopamine analog inhibited the packaging of pregenomic RNA into capsids. The present study aimed to determine the effect of dopamine on the expressions of hepatitis B virus surface and e antigens (HBsAg and HBeAg, respectively) and to elucidate the underlying mechanism.

Methods

We used dopamine-treated HBV-infected HepG2.2.15 and NTCP-G2 cells to monitor HBsAg and HBeAg expression levels. We analyzed interferon-stimulated gene 15 (ISG15) expression in dopamine-treated cells. We knocked down ISG15 and then monitored HBsAg and HBeAg expression levels. We analyzed the expression of Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway factors in dopamine-treated cells. We used dopamine hydrochloride-treated adeno-associated virus/HBV-infected mouse model to evaluate HBV DNA, HBsAg, and HBeAg expression. HBV virus was collected from HepAD38.7 cell culture medium.

Results

Dopamine inhibited HBsAg and HBeAg expression and upregulated ISG15 expression in HepG2.2.15 and HepG2-NTCP cell lines. ISG15 knockdown increased HBsAg and HBeAg expression in HepG2.2.15 cells. Dopamine-treated cells activated the JAK/STAT pathway, which upregulated ISG15 expression. In the adeno-associated virus-HBV murine infection model, dopamine downregulated HBsAg and HBeAg expression and activated the JAK-STAT/ISG15 axis.

Conclusions

Dopamine inhibits the expression of HBsAg and HBeAg by activating the JAK/STAT pathway and upregulating ISG15 expression.

Noncoding RNAs in hepatitis: Unraveling the apoptotic pathways

Hepatitis is a worldwide health issue that causes inflammation of the liver and is frequently brought on by viral infections, specifically those caused by the hepatitis B and C viruses. Although the pathophysiological causes of hepatitis are complex, recent research indicates that noncoding RNAs (ncRNAs) play a crucial role in regulating apoptosis, an essential process for maintaining liver homeostasis and advancing the illness. Noncoding RNAs have been linked to several biological processes, including apoptosis. These RNAs include microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs). Distinct expression patterns characterising different stages of the disease have been discovered, indicating dysregulation of these non-coding RNAs in liver tissues infected with hepatitis. The complex interplay that exists between these noncoding RNAs and apoptotic effectors, including caspases and members of the Bcl-2 family, plays a role in the precarious equilibrium that regulates cell survival and death during hepatitis. The purpose of this review is to provide an overview of ncRNA-mediated apoptosis in hepatitis, as well as insights into possible therapeutic targets and diagnostic indicators.

LINC00665: A Promising Biomarker in Gastrointestinal Tumors

An increasing volume of studies has reported that long non-codingRNAs (lncRNAs) are involved in the carcinogenesis of many different cancers. Especially in gastrointestinal tumors, lncRNAs are found to participate in various physiological and pathological processes. LncRNAs can regulate gene expression at multiple levels, including transcriptional, post-transcription, translational, and post-translational levels. Long intergenic non-protein coding RNA 665(LINC00665), a novel cancer-related lncRNA, is frequently dysregulated in multiple gastrointestinal tumors, including gastric and colorectal cancers, hepatocellular carcinoma, and so on. In this review, we analyzed the expression and prognostic value of LINC00665 in human gastrointestinal tumors, systematically summarized the current literature about the clinical significance of this lncRNA, and explored the regulatory mechanisms of LINC00665 as a competing endogenous RNA (ceRNA) in tumor progression. Consequently, we concluded that LINC00665 might act as a prognostic biomarker and a potential target for gastrointestinal tumor diagnosis and treatment.

Decoding hepatocarcinogenesis from a noncoding RNAs perspective

Being a leading lethal malignancy worldwide, the pathophysiology of hepatocellular carcinoma (HCC) has gained a lot of interest. Yet, underlying mechanistic basis of the liver tumorigenesis is poorly understood. The role of some coding genes and their respective translated proteins, then later on, some noncoding RNAs (ncRNAs) such as microRNAs have been extensively studied in context of HCC pathophysiology; however, the implication of long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) in HCC is indeed less investigated. As a subclass of the ncRNAs which has been elusive for long time ago, lncRNAs was found to be involved in plentiful cellular functions such as DNA, RNA, and proteins regulation. Hence, it is undisputed that lncRNAs dysregulation profoundly contributes to HCC via diverse etiologies. Accordingly, lncRNAs represent a hot research topic that requires prime focus in HCC. In this review, the authors discuss breakthrough discoveries involving lncRNAs and circRNAs dysregulation that have contributed to the contemporary concepts of HCC pathophysiology and how these concepts could be leveraged as potential novel diagnostic and prognostic HCC biomarkers. Further, this review article sheds light on future trends, thereby discussing the pathological roles of lncRNAs and circRNAs in HCC proliferation, migration, and epithelial-to-mesenchymal transition. Along this line of reasoning, future recommendations of how these targets could be exploited to achieve effective HCC-related drug development is highlighted.

Multifaceted role of NF-κB in hepatocellular carcinoma therapy: Molecular landscape, therapeutic compounds and nanomaterial approaches

The predominant kind of liver cancer is hepatocellular carcinoma (HCC) that its treatment have been troublesome difficulties for physicians due to aggressive behavior of tumor cells in proliferation and metastasis. Moreover, stemness of HCC cells can result in tumor recurrence and angiogenesis occurs. Another problem is development of resistance to chemotherapy and radiotherapy in HCC cells. Genomic mutations participate in malignant behavior of HCC and nuclear factor-kappaB (NF-κB) has been one of the oncogenic factors in different human cancers that after nuclear translocation, it binds to promoter of genes in regulating their expression. Overexpression of NF-κB has been well-documented in increasing proliferation and invasion of tumor cells and notably, when its expression enhances, it induces chemoresistance and radio-resistance. Highlighting function of NF-κB in HCC can shed some light on the pathways regulating progression of tumor cells. The first aspect is proliferation acceleration and apoptosis inhibition in HCC cells mediated by enhancement in expression level of NF-κB. Moreover, NF-κB is able to enhance invasion of HCC cells via upregulation of MMPs and EMT, and it triggers angiogenesis as another step for increasing spread of tumor cells in tissues and organs. When NF-κB expression enhances, it stimulates chemoresistance and radio-resistance in HCC cells and by increasing stemness and population of cancer-stem cells, it can provide the way for recurrence of tumor. Overexpression of NF-κB mediates therapy resistance in HCC cells and it can be regulated by non-coding RNAs in HCC. Moreover, inhibition of NF-κB by anti-cancer and epigenetic drugs suppresses HCC tumorigenesis. More importantly, nanoparticles are considered for suppressing NF-κB axis in cancer and their prospectives and results can also be utilized for treatment of HCC. Nanomaterials are promising factors in treatment of HCC and by delivery of genes and drugs, they suppress HCC progression. Furthermore, nanomaterials provide phototherapy in HCC ablation.