Re-analysis of hepatitis B virus integration sites reveals potential new loci associated with oncogenesis in hepatocellular carcinoma.

BACKGROUND: Hepatitis B virus (HBV) is a major cause of hepatocellular carcinoma (HCC). HBV DNA can get integrated into the hepatocyte genome to promote carcinogenesis. However, the precise mechanism by which the integrated HBV genome promotes HCC has not been elucidated. AIM: To analyze the features of HBV integration in HCC using a new reference database and integration detection method. METHODS: Published data, consisting of 426 Liver tumor samples and 426 paired adjacent non-tumor samples, were re-analyzed to identify the integration sites. Genome Reference Consortium Human Build 38 (GRCh38) and Telomere-to-Telomere Consortium CHM13 (T2T-CHM13 (v2.0)) were used as the human reference genomes. In contrast, human genome 19 (hg19) was used in the original study. In addition, GRIDSS VIRUSBreakend was used to detect HBV integration sites, whereas high-throughput viral integration detection (HIVID) was applied in the original study (HIVID-hg19). RESULTS: A total of 5361 integration sites were detected using T2T-CHM13. In the tumor samples, integration hotspots in the cancer driver genes, such as TERT and KMT2B, were consistent with those in the original study. GRIDSS VIRUSBreakend detected integrations in more samples than by HIVID-hg19. Enrichment of integration was observed at chromosome 11q13.3, including the CCND1 pro-moter, in tumor samples. Recurrent integration sites were observed in mitochondrial genes. CONCLUSION: GRIDSS VIRUSBreakend using T2T-CHM13 is accurate and sensitive in detecting HBV integration. Re-analysis provides new insights into the regions of HBV integration and their potential roles in HCC development.

Cabozantinib for Advanced Hepatocellular Carcinoma in the Latest Real-World Practice: A Multicenter Retrospective Analysis.

BACKGROUND: Cabozantinib was found to be effective as a second- or third-line treatment after sorafenib in patients with advanced hepatocellular carcinoma (HCC) in the phase 3 CELESTIAL trial. So far, as immunotherapy has substituted molecular target agents as the primary systemic therapy for advanced HCC, cabozantinib is extensively used in the latest real-world clinical practice in a greatly different position than that shown by the CELESTIAL trial. In the current analysis, we examined the safety and effectiveness of cabozantinib administration in real-life settings for patients with advanced HCC. METHODS: We retrospectively obtained data from patients with advanced HCC who received cabozantinib in three institutions in Japan between 14 September 2018 and 30 November 2021. RESULTS: During the study period, 23 patients with advanced HCC received cabozantinib. Our cohort included 21.7% of patients with Child-Pugh class B, and 52.2% of patients in fourth line or later. The median progression-free survival of patients given cabozantinib was 3.7 months. Regarding patients with Child-Pugh class B or administration in fourth line or later, the discontinuation rate due to adverse events in patients who initialized at 40 or 20 mg was lower than those who initialized at 60 mg (42.9% versus 75.0%). Patients who were able to continue treatment with cabozantinib for more than 3 months were more likely to undergo dose reduction than those who did not (85.7% versus 25.0%). CONCLUSIONS: Cabozantinib has recently been administered to a diverse range of patients, including those who were not enrolled in the CELESTIAL trial. Deliberate dose reduction could potentially offer clinical benefits to patients with impaired liver function. Furthermore, managing adverse events by reducing the dose could play a crucial role in extending the duration of treatment with cabozantinib. The preprint version of this work is available on https://www.researchsquare.com/article/rs-2655181/v1 .

Hyperprogressive disease during atezolizumab plus bevacizumab treatment in patients with advanced hepatocellular carcinoma from Japanese real-world practice.

BACKGROUND: Hyperprogressive disease (HPD) is a phenomenon with greatly accelerated tumor growth and clinical deterioration rates compared to pre-therapy, in patients treated with immune checkpoint inhibitors (ICI). The aim of this study is to clarify the reality of HPD in patients with advanced hepatocellular carcinoma (HCC) who were treated with atezolizumab plus bevacizumab (Atez/Bev) using tumor dynamics. METHODS: Medical records of consecutive patients with advanced HCC who were treated with Atez/Bev were retrospectively reviewed. HPD was defined as a more than two- or fourfold increase in tumor growth rate (TGR) or tumor growth kinetics rate (TGKR) before and after treatment. Overall survival (OS) and baseline characteristics with or without HPD were analyzed. RESULTS: A total of 85 patients were included in the analysis. When HPD was defined as a twofold of TGR or TGKR, 8 patients (8/85, 9.4%) had HPD and 11 had PD without HPD. A total of 5 patients (5/85, 5.9%) were diagnosed with HPD and 14 with PD without HPD when HPD was defined as a fourfold of TGR or TGKR. No significant difference was observed in the baseline characteristics between HPD and non-HPD. CONCLUSION: The prevalence of HPD in patients with advanced HCC treated with Atez/Bev was lower than those treated with nivolumab monotherapy. The HPD mechanism in ICI combined with antibodies targeting vascular endothelial growth factor (VEGF) remains to be elucidated.

Alteration of the tumor microenvironment by pharmacological inhibition of EZH2 in hepatocellular carcinoma.

Enhancer of zeste homolog 2 (EZH2), a core component of polycomb repressive component 2 is overexpressed in a variety of cancers and recognized as a therapeutic target molecule. However, EZH2 possesses immunomodulatory functions in the tumor microenvironment (TME). The impact of EZH2 on TME of hepatocellular carcinoma (HCC) using immunocompetent mouse model was evaluated in the present study. UNC1999, an EZH2 inhibitor, impaired growth of the murine HCC cells (H22 cells) and induced apoptosis in a dose-dependent manner. Although UNC1999 significantly inhibited the growth of H22 cells-derived and Hepa1-6 cells-derived tumors in nonobese diabetic/severe combined immunodeficiency mice, its antitumor effect was diminished in allogenic BALB/c and C57BL/6 mice. Flow cytometric analyses of TME cells in BALB/c mice demonstrated a significant decrease in the number of interferon­Î³+ CD8+ T cells and regulatory T cells and a significant increase in the number of myeloid-derived suppressor cells (MDSCs). Administration of Gr-1 neutralizing antibody concomitant with UNC1999 restored antitumor effect accompanied by an increase in the number of CD8+ T cells followed by a decrease in the number of MDSCs. Chemokine antibody array demonstrated an enhanced expression of chemokines responsible for MDSCs recruitment such as C5a, CCL8, and CCL9. In conclusion, the study results demonstrated that EZH2 inhibitor contributed to attenuation of tumor immunity caused by TME arrangement. Combination therapy with EZH2 inhibitors and agents that reduce MDSCs might represent a novel therapeutic strategy for HCC.

Miglustat, a glucosylceramide synthase inhibitor, mitigates liver fibrosis through TGF-ß/Smad pathway suppression in hepatic stellate cells.

Transforming growth factor (TGF)-ß/Smad pathway is implicated in the pathogenesis of liver fibrosis, a condition characterized by excessive deposition of extracellular matrix (ECM) proteins such as collagen in response to chronic inflammation. It has been reported that ceramide regulates collagen production through TGF-ß/Smad pathway activation. In this study, we examined whether miglustat, an inhibitor of glucosylceramide synthase, can suppress liver fibrosis by reducing TGF-ß/Smad pathway activity. Human hepatic stellate cells (HHSteCs) were cultured with TGF-ß and multiple miglustat concentrations to examine dose-dependent effects on the expression levels of ECM-related genes and Smad proteins. To evaluate the efficacy of miglustat for fibrosis mitigation, C57BL/6 mice were treated with carbon tetrachloride (CCl4) for 4 weeks to induce liver fibrosis, followed by combined CCl4 plus miglustat for a further 2 weeks. To examine if miglustat can also prevent fibrosis, mice were treated with CCl4 for 2 weeks, followed by CCl4 plus miglustat for 2 weeks. Miglustat dose-dependently downregulated expression of α-smooth muscle actin and ECM components in TGF-ß-treated HHSteCs. Both phosphorylation and nuclear translocation of Smad2 and Smad3 were also suppressed by miglustat treatment. Sirius-Red staining and hydroxyproline assays of model mouse liver samples revealed that miglustat reduced fibrosis, an effect accompanied by decreased expression of ECM. Our findings suggest that miglustat can both prevent and reverse liver fibrosis by inhibiting TGF-ß/Smad pathway.

Clinical effects and emerging issues of atezolizumab plus bevacizumab in patients with advanced hepatocellular carcinoma from Japanese real-world practice.

BACKGROUND: Although the efficacy of atezolizumab has been demonstrated in randomized controlled trials, its long-term efficacy and association with adverse events in real-world practice are unknown. This study was designed to shed light on these issues. METHODS: In this multicenter retrospective study, data were collected from patients with advanced hepatocellular carcinoma treated with atezolizumab plus bevacizumab in seven institutions in Japan. The authors focused on the efficacy and adverse events related to vascular endothelial growth factor (VEGF) inhibition. RESULTS: A total of 123 patients were enrolled in this study. The median progression-free survival (PFS) for the first-line treatment group was 8.0 months (95% confidence interval [CI], 6.1-9.9), whereas the median PFS for the second- or later-line treatment group was 4.1 months (95% CI, 2.6-5.7), which was significantly worse than that of the first-line treatment group (p = .005). Twenty-seven patients had interrupted bevacizumab treatment. Proteinuria accounted for the largest proportion of bevacizumab treatment interruptions. The cumulative incidence rate of bevacizumab interruption due to anti-VEGF-related adverse events was significantly higher in patients with hypertension and/or diabetes mellitus than in those without (p = .026). The landmark analysis showed that patients experienced bevacizumab interruption by 24 weeks from treatment initiation had poorer PFS than those who did not (p = .013). CONCLUSIONS: The PFS of atezolizumab plus bevacizumab as first-line treatment mostly replicates that of a global phase 3 trial. Interrupted bevacizumab treatment was more common in patients with hypertension and/or diabetes mellitus, which may be associated with worsening long-term PFS. PLAIN LANGUAGE SUMMARY: Atezolizumab plus bevacizumab has been the standard front line systemic therapy for advanced hepatocellular carcinoma. With the growing incidence of fatty liver due to metabolic syndrome as a background liver disease for hepatocellular carcinoma, the rate of comorbid hypertension and diabetes mellitus has been increasing accordingly. The present study demonstrated the cumulative incidence rate of bevacizumab interruption due to anti-VEGF-related adverse events was significantly higher in patients with hypertension and/or diabetes mellitus. The landmark analysis clarified that interruption of bevacizumab might be a risk of impaired efficacy of atezolizumab plus bevacizumab over the long term in patients with advanced hepatocellular carcinoma.

Antiviral Compounds Screening Targeting HBx Protein of the Hepatitis B Virus.

A functional cure of hepatitis B virus (HBV) infection or HB antigen loss is rarely achieved by nucleos(t)ide analogs which target viral polymerase. HBx protein is a regulatory protein associated with HBV replication. We thought to identify antiviral compounds targeting HBx protein by analyzing HBx binding activity. Recombinant GST-tagged HBx protein was applied on an FDA-approved drug library chip including 1018 compounds to determine binding affinity by surface plasmon resonance imaging (SPRi) using a PlexArray HT system. GST protein alone was used for control experiments. Candidate compounds were tested for anti-HBV activity as well as cell viability using HepG2.2.15.7 cells and HBV-infected human hepatocytes. Of the 1018 compounds screened, 24 compounds showed binding to HBx protein. Of the top 6 compounds with high affinity to HBx protein, tranilast was found to inhibit HBV replication without affecting cell viability using HepG2.2.15.7 cells. Tranilast also inhibited HBV infection using cultured human hepatocytes. Tranilast reduced HB antigen level dose-dependently. Overall, theSPRi screening assay identified novel drug candidates targeting HBx protein. Tranilast and its related compounds warrant further investigation for the treatment of HBV infection.