Liver Injury and Its Impact on Prognosis in Patients with HBV-Related Hepatocellular Carcinoma Undergoing Transarterial Chemoembolization Combined with Tyrosine Kinase Inhibitors Plus Immune Checkpoint Inhibitors.

Purpose: Recently, the triple therapy of transarterial chemoembolization (TACE) combined with tyrosine kinase inhibitors (TKIs) plus immune checkpoint inhibitors (ICIs) has become a new treatment option for advanced or unresectable hepatocellular carcinoma (HCC) patients. We aimed to explore the liver injury and its effect on overall survival (OS) in patients treated with this combination therapy. Patients and Methods: Patients with HBV-related HCC who were treated with TACE-TKIs-ICIs from January 2020 to December 2021 were enrolled. Liver injury and survival time were the main endpoints of the study. Logistic regression analysis was used to analyze the factors associated with liver injury. Cox regression and Kaplan-Meier analysis were used to determine prognostic factors for OS. Results: As of March 2022, 52 of the 119 enrolled patients developed any grade hepatotoxicity: 15 cases with grade 1, 19 cases with grade 2, 16 cases with grade 3 and 2 cases with grade 4. Our analysis indicated that lack of antiviral prevention was a risk factor for liver injury (OR = 0.149; 95% CI: 0.050-0.442; P = 0.001). The findings suggested that liver injury events (HR = 1.912; 95% CI: 1.031-3.546; P = 0.040) was associated with patient death. The median OS of patients without liver injury, grade 1-2 and grade 3-4 liver injury were undefined, 13.7 months and 11.1 months, respectively (log-rank P = 0.034). Conclusion: Liver injury adverse events are common in HBV-related HCC patients treated with TACE-TKIs-ICIs. Patients who developed liver injury had a poor prognosis. For HBV-related HCC patients, effective prophylactic antiviral therapy and regular liver function testing are required before and during this triple therapy.

HBV reactivation and its effect on survival in HBV-related hepatocarcinoma patients undergoing transarterial chemoembolization combined with tyrosine kinase inhibitors plus immune checkpoint inhibitors.

Objective: This study aimed to access hepatitis B virus (HBV) reactivation and its effect on survival in HBV-related hepatocarcinoma (HCC) patients who underwent transarterial chemoembolization (TACE) combined with tyrosine kinase inhibitors (TKIs) plus immune checkpoint inhibitors (ICIs). Methods: In this single-center retrospective study, we enrolled 119 HBV-related unresectable advanced HCC patients receiving TACE combined with TKIs plus ICIs. Risk factors for HBV reactivation were analyzed by logistic regression. Kaplan-Meier method was applied to draw the survival curve, and log-rank test was used to compare survival between patients with and without HBV reactivation. Results: A total of 12 patients (10.1%) encountered HBV reactivation in our study, of which only 4 patients received antiviral prophylaxis. The incidence of HBV reactivation was 1.8% (1/57) in patients with detectable baseline HBV DNA and 4.2% (4/95) in patients with antiviral prophylaxis respectively. Lack of prophylactic antiviral treatment (OR=0.047, 95%CI 0.008-0.273, P=0.001) and undetectable HBV DNA (OR=0.073, 95%CI 0.007-0.727, P=0.026) were independent risk factors for HBV reactivation. The median survival time (MST) for all patients was 22.4 months. No survival difference was observed in patients with or without HBV reactivation. (MST: undefined vs 22.4 months, log-rank test: P=0.614). Conclusion: HBV reactivation could occur in HBV-related HCC patients who treated with TACE in combination with TKIs plus ICIs. Before and during the combination treatment, it is necessary to routinely monitor HBV DNA and to take effective prophylactic antiviral therapy.

Development and validation of a nomogram to predict recompensation in HBV-related cirrhosis with ascites as the single first decompensating event.

BACKGROUND AND OBJECTIVE: Little is known about the influencing factors for recompensation in HBV-related cirrhosis patients with ascites as the single first decompensating event and it's necessary to build a prediction model for these patients. METHODS: Hepatitis B virus-related cirrhosis patients with ascites hospitalized for the first decompensation were included and they were divided into the training cohort (2010.03-2020.03) and the validation cohort (2020.04-2022.04). All patients received antiviral therapy within 3 months before admission or immediately after admission. Recompensation is defined as the patient's ascites disappeared without diuretics, which were maintained for more than 1 year and no other decompensated complications, hepatocellular carcinoma, or liver transplantation occurred. The nomogram was developed from a training cohort of 279 patients and validated in another cohort of 72 patients. RESULTS: Totally, 42.7% of the decompensated patients achieved recompensation. According to the results of logistic regression and competing risk analysis, six independent factors associated with recompensation were found and these factors comprised the nomogram: age, alanine aminotransferase (ALT), albumin (ALB), serum sodium (Na), alpha-fetoprotein (AFP), and maintained virological response (MVR). Through external validation, the area under the receiver operating characteristic curve (AUC) of the nomogram was 0.848 (95% CI: 0.761, 0.936), which was significantly better than CTP, MELD, MELDNa, MELD 3.0, and ALBI grade. CONCLUSIONS: Age, ALT, ALB, Na, AFP, and MVR are closely related to the recompensation. The nomogram developed based on these items can accurately predict the possibility of recompensation in hepatitis B cirrhosis patients with ascites as the single first decompensating event.

The emerging role of DEAD/H-box helicases in hepatitis B virus infection.

DEAD/H-box helicases are an essential protein family with a conserved motif containing unique amino acid sequences (Asp-Glu-Ala-Asp/His). Current evidence indicates that DEAD/H-box helicases regulate RNA metabolism and innate immune responses. In recent years, DEAD/H-box helicases have been reported to participate in the development of a variety of diseases, including hepatitis B virus (HBV) infection, which is a significant risk factor for hepatic fibrosis, cirrhosis, and liver cancer. Furthermore, emerging evidence suggests that different DEAD/H-box helicases play vital roles in the regulation of viral replication, based on the interaction of DEAD/H-box helicases with HBV and the modulation of innate signaling pathways mediated by DEAD/H-box helicases. Besides these, HBV can alter the expression and activity of DEAD/H-box helicases to facilitate its biosynthesis. More importantly, current investigation suggests that targeting DEAD/H-box helicases with appropriate compounds is an attractive treatment strategy for the virus infection. In this review, we delineate recent advances in molecular mechanisms relevant to the interplay of DEAD/H-box helicase and HBV and the potential of targeting DEAD/H-box helicase to eliminate HBV infection.

Regulation of Pattern-Recognition Receptor Signaling by HBX During Hepatitis B Virus Infection.

As a small DNA virus, hepatitis B virus (HBV) plays a pivotal role in the development of various liver diseases, including hepatitis, cirrhosis, and liver cancer. Among the molecules encoded by this virus, the HBV X protein (HBX) is a viral transactivator that plays a vital role in HBV replication and virus-associated diseases. Accumulating evidence so far indicates that pattern recognition receptors (PRRs) are at the front-line of the host defense responses to restrict the virus by inducing the expression of interferons and various inflammatory factors. However, depending on HBX, the virus can control PRR signaling by modulating the expression and activity of essential molecules involved in the toll-like receptor (TLR), retinoic acid inducible gene I (RIG-I)-like receptor (RLR), and NOD-like receptor (NLR) signaling pathways, to not only facilitate HBV replication, but also promote the development of viral diseases. In this review, we provide an overview of the mechanisms that are linked to the regulation of PRR signaling mediated by HBX to inhibit innate immunity, regulation of viral propagation, virus-induced inflammation, and hepatocarcinogenesis. Given the importance of PRRs in the control of HBV replication, we propose that a comprehensive understanding of the modulation of cellular factors involved in PRR signaling induced by the viral protein may open new avenues for the treatment of HBV infection.

Sirtuins as Potential Therapeutic Targets for Hepatitis B Virus Infection.

Sirtuins (SIRTs) are well-known histone deacetylases that are capable of modulating various cellular processes in numerous diseases, including the infection of hepatitis B virus (HBV), which is one of the primary pathogenic drivers of liver cirrhosis and hepatocellular carcinoma. Mounting evidence reveals that HBV can alter the expression levels of all SIRT proteins. In turn, all SIRTs regulate HBV replication via a cascade of molecular mechanisms. Furthermore, several studies suggest that targeting SIRTs using suitable drugs is a potential treatment strategy for HBV infection. Here, we discuss the molecular mechanisms associated with SIRT-mediated upregulation of viral propagation and the recent advances in SIRT-targeted therapy as potential therapeutic modalities against HBV infection.

Calcium signaling in hepatitis B virus infection and its potential as a therapeutic target.

As a ubiquitous second messenger, calcium (Ca2+) can interact with numerous cellular proteins to regulate multiple physiological processes and participate in a variety of diseases, including hepatitis B virus (HBV) infection, which is a major cause of hepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. In recent years, several studies have demonstrated that depends on the distinct Ca2+ channels on the plasma membrane, endoplasmic reticulum, as well as mitochondria, HBV can elevate cytosolic Ca2+ levels. Moreover, within HBV-infected cells, the activation of intracellular Ca2+ signaling contributes to viral replication via multiple molecular mechanisms. Besides, the available evidence indicates that targeting Ca2+ signaling by suitable pharmaceuticals is a potent approach for the treatment of HBV infection. In the present review, we summarized the molecular mechanisms related to the elevation of Ca2+ signaling induced by HBV to modulate viral propagation and the recent advances in Ca2+ signaling as a potential therapeutic target for HBV infection. Video Abstract.

Interleukin-34 mediated by hepatitis B virus X protein via CCAAT/enhancer-binding protein α contributes to the proliferation and migration of hepatoma cells.

OBJECTIVES: Interleukin-34 (IL-34) is associated with hepatitis B virus (HBV) infection and hepatocellular carcinoma (HCC). However, the role and associated mechanisms of IL-34 in HBV-related HCC remain unclear. In this study, the expression, biological function and associated mechanisms of IL-34 in HBV-related HCC cells were investigated. METHODS: IL-34 expression induced by HBV and HBV X (HBX) gene was measured in hepatoma cells. The role of CCAAT/enhancer-binding protein α (CEBP/α) in HBX-induced IL-34 expression was examined. The signal pathways involved in the expression of CEBP/α and IL-34 induced by HBX were assessed. The role of IL-34 in the proliferation and migration of HCC cells, and related mechanisms were explored. RESULTS: Dependent on HBX, HBV increased IL-34 expression in hepatoma cells, and HBX upregulated and interacted with CEBP/α to enhance the activity of IL-34 promoters. CEBP/α mediated by HBX was associated with the activation of PI3-K and NF-κB pathways to promote IL-34 expression. Via CSF1-R and CD138, IL-34 promoted the proliferation and migration of hepatoma cells, and contributed to the activation of ERK and STAT3 pathways and the upregulation of Bcl-xl and c-Myc mediated by HBX. CONCLUSION: We demonstrate that IL-34 contributes to HBX-mediated functional abnormality of HCC cells and provides a novel insight into the molecular mechanism of carcinogenesis mediated by HBX.

Amino acid sequence analysis in patients with chronic HCV genotype 1b infection during pegylated interferon-α2a and ribavirin therapy.

BACKGROUND: Amino acid variations in several HCV genomic regions have been reported to be associated with response to interferon (IFN)-α plus ribavirin (RBV) combination therapy. However, the results remain controversial. In this study, we further investigated the amino acid variation of full-length HCV genome and its correlation to the response to pegylated interferon (PEG-IFN)-α2a and RBV combination therapy in patients with HCV genotype 1b (HCV-1b). METHODS: We retrospectively analysed 18 chronic HCV-1b patients (9 with rapid virological response and 9 non-response to therapy) treated with PEG-IFN-α2a plus RBV for 48 weeks. The nearly full-length HCV genome sequence was amplified by reverse transcription (RT)-PCR followed by cloning and sequencing. Genetic diversity differences between two groups were analysed including the number of amino acid variations in the HCV polyprotein and the mean pair-wise protein distance. RESULTS: No single amino acid variations were closely associated with treatment outcome. However, the number of amino acid mutations in the NS5B region especially in the thumb domain and in the NS5A-V3 region was associated with the response to PEG-IFN-α/RBV therapy (P=0.002 and P=0.029, respectively). The number of substitutions in the NS5B region was significantly correlated with the numbers of substitutions in the V3 region (r=0.568, P=0.027). CONCLUSIONS: Amino acid substitutions in the NS5B region especially in the thumb domain and the NS5A-V3 region may play a role in the response to combined PEG-IFN-α2a and RBV therapy in HCV-1b patients.

Synergistic effects of soluble PD-1 and IL-21 on antitumor immunity against H22 murine hepatocellular carcinoma.

Cancer immunotherapies are designed to elicit T-cell responses that inhibit tumor growth. Previous studies have demonstrated that interleukin 21 (IL-21) is a promising cytokine for cancer immunotherapy due to its ability to induce the immunity of T cells and natural killer cells, whereas blockade of the interaction of programmed death receptor-1 (PD-1) with its ligand (PD-L1) reduces peripheral tolerance. In the current study, we investigated IL-21 alone and in combination with soluble PD-1 (sPD-1) for the treatment of experimental H22 murine hepatocarcinoma. The naked plasmids pmIL-21 and/or psPD-1 were used for local gene transfer by injection. In these assays, sPD-1 combined with IL-21 was found to significantly inhibit the growth of the tumors in mice. Combined treatment with IL-21 and sPD-1 enhanced the antitumor immune response compared with that induced by IL-21 alone. Combined treatment was found to increase CTL cytotoxicity, increase the number of CTLs and NK cells in splenocytes, upregulate the cytokines IFN-γ and IL-2 and downregulate IL-10. Thus, immunotherapy with IL-21 in combination with sPD-1 was found to induce a more efficacious antitumor immune response, which may have potential clinical implications.

[Effect of KLF6 and its splice variant KLF6V on proliferation and differentiation of human hepatocellular carcinoma HepG2 cells].

OBJECTIVE: To investigate the roles of Kruppel-like factor 6 (KLF6) and its splice variant KLF6V on suppressing growth and inducing differentiation of human hepatocellular carcinoma hepG2 cells. METHOD: KLF6V cDNA was amplificated by RT-PCR from human hepatocellular carcinoma (HCC) tissue and then sequenced. The recombinant vectors expressing KLF6 variant (KLF6V) were constructed using molecular clone technology based on established plasmid pcDNA3.1A(-)/wtKLF6. KLF6V or KLF6-transfected HepG2 cells were established after being screened with G418. Growth activity of HepG2/KLF6 or HepG2/KLF6V cells was detected by in vitro MTT assay. Expression of p21WAF1 or cyclin D1 protein was detected by Western blot, and expressions of AFP or ALB protein were measured by radioimmunoassay. RESULTS: A novel alternatively spliced transcript of the human KLF6 gene was found and its sequencing revealed that the variant form of KLF6 lacked 126nt and its encoded protein products had a deletion of 42 aa near the COOH-terminal amino acid in comparison with full-length KLF6. Although KLF6 alternative splicing was present in both normal and cancerous tissues, expression of the KLF6 splice variants seemed to be up-regulated in HCCs tissues. The isoform of KLF6 proteins antagonized the ability of wild-type KLF6 to up-regulate p21 expression or down-regulate cyclin D1 expression and suppress HepG2 cell proliferation. KLF6 gene increased albumin production and decreased alpha fetoprotein production of the cells. CONCLUSION: The isoform of KLF6 protein, present in HCC tissue, antagonizes the ability of wild-type KLF6 to suppress cell proliferation and induce cellular differentiation.

Inactivation of the tumor suppressor Krüppel-like factor 6 (KLF6) by mutation or decreased expression in hepatocellular carcinomas.

BACKGROUND AND AIM: The Krüppel-like transcription factor KLF6 is a novel tumor-suppressor gene. It was inactivated in human prostate cancer and other tumors tissue, as the result of frequent mutation and loss of heterozygosity (LOH). However, there is no data reporting the levels of KLF6 both mRNA and protein in hepatocellular carcinomas (HCCs). We therefore detected mutations and expression of KLF6 in HCC tissues and further observed the effect of it on cell growth in HCC cell lines. METHODS: We analyzed the exon-2 of KLF6 gene by direct DNA sequencing, and detected the expression of KLF6 by RT-PCR and Western blot in 23 HCC tissues and corresponding nontumorous tissues. Loss of growth suppressive effect of the HCC-derived KLF6 mutant was characterized by in vitro growth curves plotted, flow cytometry and Western blotting. RESULTS: KLF6 mutations were found in 2 of 23 HCC tissues and one of mutations was missense. Expression of KLF6 mRNA or protein was down-regulated in 8 (34.7%) or 9 (39.1%) of 23 HCC tissues. Wild-type KLF6 (wtKLF6) inhibited cellular proliferation and prolonged G1-S transition by inducing the expression of p21WAF1 following stable transfection into cultured HepG2 cells, but tumor-derived KLF6 mutant (mKLF6) had no effects. CONCLUSION: Our findings suggest that KLF6 may be involved in pathogenesis of HCC.

[Application of PCR-based tRNAval Pol III-shRNA expression cassettes in screening of efficient siRNA for inhibiting hepatitis B virus].

OBJECTIVE: To screen efficient siRNA for inhibiting hepatitis B virus using the technique of PCR-based tRNA(val) Pol III-shRNA expression cassettes (SECs). METHODS: Based on core gene sequence of HBV, five target sites of siRNA were designed. tRNAval Pol III-shRNA expression cassettes produced by one-step overlapping extension PCR strategy were co-transfected with HBV C gene and pC-EGFP plasmid into AD293 cells respectively. Forty-eight hours after transfection, fluorescence of HBVC-GFP protein was detected by fluorescence-activated cell sorting (FACS); HBV C mRNA was detected by semi-quantitative RT-PCR. HBV-producing HepG2. 2. 15 cells were transfected with selected SECs for 72 h, HBsAg and HBeAg in the cell culture medium were detected by radioimmunoassay assay (RIA). HBV pgRNA from cell total RNA was detected by semi-quantitative PCR. RESULT: Co-transfection with pC-GFP plasmid and SECs into AD293 cells resulted in inhibition expression of HBV C gene and decrease of EGFP fluorescence intensity. SEC-492i showed most significant inhibition effect on HBV C-EGFP expression compared with other SECs. Selected SEC-492i or SEC-282i targeting core gene could efficiently decrease expression of HBeAg and the level of HBV pgRNA in a dose-dependent manner. SEC-492i inhibited HBV replication and antigen expression in a more efficient way than SEC-282i at the same final concentration. CONCLUSION: The expressed shRNA, which targets sites on HBV C mRNA in 492i, is to have having most efficient RNAi effect. tRNAval Pol III-shRNA expression cassettes produced by one-step overlapping extension PCR strategy should be useful for identification of optimal siRNA.

[Mutations of the tumor suppressor Kruppel-like factor 6 (KLF6) gene in hepatocellular carcinoma and its effect of growth suppression on human hepatocellular carcinoma cell line HepG2].

OBJECTIVE: To explore the mutated KLF6 gene in hepatocellular carcinoma (HCC) and to characterize its behavior in human hepatocellular carcinoma cell line HepG2. METHODS: We analyzed the DNA isolated from 23 hepatocellular carcinoma tissues and their adjacent nontumor tissues by polymerase chain reaction (PCR). Direct sequencing was used to establish the incidence of mutation in exon2 of the KLF6 gene. Loss of growth suppressive function of the HCC-derived KLF6 mutants was characterized by in vitro analyzing alteration of cell cycle and MTT assay. Expression of p21WAF1, a possible downstream gene of KLF6, was detected in human hepatocellular carcinoma cell line HepG2 transiently transfected with KLF6 genes. RESULTS: Mutations of KLF6 were found in 2 of the 23 (8.7%) hepatocellular carcinomas. The two mutations were located in the transactivation domain and one of them resulted in single amino acid substitution of TGG (W) by GGG (G) at codon 162. Unlike the wild-type KLF6, cancer-derived KLF6 mutants neither suppressed growth nor induced p21WAF1 following transfection into culture cells. CONCLUSIONS: Mutations of the KLF6 gene may play a role in the pathogenesis of HCC, but are not the dominating mechanism resulting in inactivation of KLF6 functions. KLF6 suppresses hepatocellular carcinoma cell proliferation partly through upregulating expression of the p21WAF1 gene.

[Inhibition of HBs-GFP fusion gene expression by RNA interference].

OBJECTIVE: To develop an effective report gene system to test the effect of small interfering RNA (siRNA). METHODS: HBV S gene was fused with enhanced green fluorescent protein (EGFP) gene to form HBs-GFP and the plasmid containing HBs-GFP was constructed. A vector expressing small hairpin RNA (shRNA) pAVU6 + 4sh357 was also constructed. Two plasmids were co-transfected into HepG2 cells transiently. The fluorescence of HBs-GFP was detected by fluorescence-activated cell sorting (FACS). The mRNA expression in HepG2 cells was detected by conventional RT-PCR and real-time PCR. RESULTS: siRNA inhibited the expression of HBs-GFP 72 hours post transfection. The fluorescence of HBs-GFP in HepG2 cells treated with pAVU6+4sh357 was reduced by 55.4% compared with that of controls. The HBs-GFP expression in HepG2 cells treated with pAVU6+4sh357 was reduced by 76.3% and 90% as measured with conventional RT-PCR and real-time PCR, respectively. CONCLUSION: This investigation demonstrated siRNA derived from shRNA expression vectors can inhibit the expression of HBs-GFP in HepG2 cells.