Telomerase reverse transcriptase (TERT) mutations are reportedly the most frequent somatic genetic alterations in hepatocellular carcinoma (HCC). An integrative analysis of TERT-telomere signaling during hepatocarcinogenesis is lacking. This study aimed to investigate the clinicopathological association and prognostic value of TERT gene alterations and telomere length in HCC patients undergoing hepatectomy as well as transarterial chemotherapy (TACE). TERT promoter mutation, expression, and telomere length were analyzed by Sanger sequencing and real-time PCR in 305 tissue samples. Protein–protein interaction (PPI) analysis was performed to identify a set of genes that physically interact with TERT. The PPI analysis identified eight key TERT-interacting genes, namely CCT5, TUBA1B, mTOR, RPS6KB1, AKT1, WHAZ, YWHAQ, and TERT. Among these, TERT was the most strongly differentially expressed gene. TERT promoter mutations were more frequent, TERT expression was significantly higher, and telomere length was longer in tumors versus non-tumors. TERT promoter mutations were most frequent in HCV-related HCCs and less frequent in HBV-related HCCs. TERT promoter mutations were associated with higher TERT levels and longer telomere length and were an independent predictor of worse overall survival after hepatectomy. TERT expression was positively correlated with tumor differentiation and stage progression, and independently predicted shorter time to progression after TACE. The TERT-telomere network may have a crucial role in the development and progression of HCC. TERT-telomere abnormalities might serve as useful biomarkers for HCC, but the prognostic values may differ with tumor characteristics and treatment.

Background/Aims: Lenvatinib was recently approved as a first-line oral multikinase inhibitor for unresectable hepatocellular carcinoma (HCC). In this study, we aimed to compare the efficacy and safety of lenvatinib and sorafenib for the treatment of unresectable HCC in patients with prior failure of transarterial treatment. Methods: Between January 2019 and September 2020, 98 unresectable HCC patients treated with lenvatinib or sorafenib as salvage therapy were enrolled from five Korean university-affiliated hospitals. Progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and disease control rate were calculated to assess the antitumor response. Results: A total of 43 and 55 patients were treated with lenvatinib and sorafenib, respectively, as salvage therapy after the failure of transarterial treatments. The median PFS was 4.97 months in the lenvatinib group and 2.47 months in the sorafenib group (p = 0.001, log-rank test). The ORR was significantly higher in the lenvatinib group (25.6%) than in the sorafenib group (3.6%, p = 0.002). Use of lenvatinib over sorafenib (hazard ratio: 0.359, 95% confidence interval: 0.203–0.635, p < 0.001) was the most significant factor for a favorable PFS after the failure of transarterial treatments in all enrolled patients. For favorable OS, achieving objective response was the significant factor (hazard ratio 0.356, 95% confidence interval: 0.132–0.957, p = 0.041). There were no significant differences in the safety profile between the two groups. Conclusions: In this real-world study, lenvatinib was demonstrated to be more efficacious than sorafenib as a salvage therapy for transarterial treatments in unresectable HCC.

A predictive biomarker of immune checkpoint inhibitor (ICI)-based treatments in hepatocellular carcinoma (HCC) has not been clearly demonstrated. In this study, we focused on the infiltration and programmed death ligand 1 (PD-L1) expression of tumor-associated macrophages (TAMs) in the tumor microenvironment of HCC. Immunohistochemistry demonstrated that PD-L1 was preferentially expressed on CD68⁺ macrophages in the tumor microenvironment of HCC, suggestive of its expression in TAMs rather than in T cells or tumor cells (P < 0.05). A co-culture experiment using activated T cells and M2 macrophages confirmed a significant increase in T cell functionality after the pretreatment of M2 macrophages with anti-PD-L1. Syngeneic mouse model experiments demonstrated that TAMs expressed PD-L1 and tumors treated with anti-PD-L1 showed smaller diameters than those treated with IgG. In these mice, anti-PD-L1 treatment increased activation markers in intratumoral CD8⁺ T cells and reduced the size of the TAM population. Regarding nivolumab-treated patients, three of eight patients responded to the anti-PD-1 treatment. The percentage of Ki-67-positive CD4⁺ and CD8⁺ T cells was higher in responders than non-responders after nivolumab. Overall, PD-L1 expression on TAMs may be targeted by immune-based HCC treatment, and ICI treatment results in the reinvigoration of exhausted CD8⁺ T cells in HCC.

Purpose: Given its heterogeneity and diverse clinical outcomes, precise subclassification of Barcelona Clinic Liver Cancer stage C (BCLC-C) hepatocellular carcinoma (HCC) is required for appropriately determining patient prognosis and selecting treatment. Experimental Design: We recruited 2,626 patients with BCLC-C HCC from multiple centers, comprising training/test (n = 1,693) and validation cohorts (n = 933). The XGBoost model was chosen for maximum performance among the machine learning (ML) models. Patients were categorized into low-, intermediate-, high-, and very high-risk subgroups based on the estimated prognosis, and this subclassification was named the CLAssification via Machine learning of BCLC-C (CLAM-C). Results: The areas under the receiver operating characteristic curve of the CLAM-C for predicting the 6-, 12-, and 24-month survival of patients with BCLC-C were 0.800, 0.831, and 0.715, respectively—significantly higher than those of the conventional models, which were consistent in the validation cohort. The four subgroups had significantly different median overall survivals, and this difference was maintained among various patient subgroups and treatment modalities. Immune-checkpoint inhibitors and transarterial therapies were associated with significantly better survival than tyrosine kinase inhibitors (TKI) in the low- and intermediate-risk subgroups. In cases with first-line systemic therapy, the CLAM-C identified atezolizumab–bevacizumab as the best therapy, particularly in the high-risk group. In cases with later-line systemic therapy, nivolumab had better survival than TKIs in the low-to-intermediate-risk subgroup, whereas TKIs had better survival in the high- to very high-risk subgroup. Conclusions: ML modeling effectively subclassified patients with BCLC-C HCC, potentially aiding treatment allocation. Our study underscores the potential utilization of ML modeling in terms of prognostication and treatment allocation in patients with BCLC-C HCC.

Although hepatitis B virus (HBV) integration into the cellular genome is well known in HCC (hepatocellular carcinoma) patients, its biological role still remains uncertain. This study investigated the patterns of HBV integration and correlated them with TERT (telomerase reverse transcriptase) alterations in paired tumor and non-tumor tissues. Compared to those in non-tumors, tumoral integrations occurred less frequently but with higher read counts and were more preferentially observed in genic regions with significant enrichment of integration into promoters. In HBV-related tumors, TERT promoter was identified as the most frequent site (38.5% (10/26)) of HBV integration. TERT promoter mutation was observed only in tumors (24.2% (8/33)), but not in non-tumors. Only 3.00% (34/1133) of HBV integration sites were shared between tumors and non-tumors. Within the HBV genome, HBV breakpoints were distributed preferentially in the 3’ end of HBx, with more tumoral integrations detected in the preS/S region. The major genes that were recurrently affected by HBV integration included TERT and MLL4 for tumors and FN1 for non-tumors. Functional enrichment analysis of tumoral genes with integrations showed enrichment of cancer-associated genes. The patterns and functions of HBV integration are distinct between tumors and non-tumors. Tumoral integration is often enriched into both human-virus regions with oncogenic regulatory function. The characteristic genomic features of HBV integration together with TERT alteration may dysregulate the affected gene function, thereby contributing to hepatocarcinogenesis.

Hepatitis B (HB) is an infectious disease with unfavorable consequence for patients and involved in chronic inflammation of liver. The present study aimed to investigate whether High-mobility group protein B (HMGB)1/receptor for advanced glycation end products (RAGE) aggravates inflammation enhancing the expression of interleukin (IL)-17. Mild and severe HB liver tissue and peripheral blood samples were obtained intra-operatively. Histological analysis of the livers was performed by immunohistochemistry. IL-1β and IL-6 of liver tissue were detected by confocal microscopy staining. Relative mRNA expression was measured by real-time PCR and protein levels were measured by enzyme-linked immunosorbent assay. HMGB1, RAGE and IL-17 expression is increased in liver of HB patients with acute on chronic liver failure (ACLF) compared to healthy controls. HMGB1 treatment induced inflammatory cytokines including IL-17 in peripheral blood cells of HB patients. IL-17 also induced the expression of RAGE and IL-1β in peripheral blood cells of HB patients with ACLF. On the other hands, the inhibitory factor of p38 and nuclear factor-kappa B reduced the expression of RAGE and IL-1β in peripheral blood cells HB patients with ACLF. HMGB1, RAGE and IL-17 expression is increased in liver of severe HB patients. HMGB1 and RAGE interaction may contribute to the inflammation of liver enhancing the expression of IL-17, which can be possibly restored through the decline of the HMGB1/RAGE axis.