Potential utility of l-carnitine for preventing liver tumors derived from metabolic dysfunction-associated steatohepatitis.

BACKGROUND: Recent reports have unveiled the potential utility of l-carnitine to alleviate metabolic dysfunction-associated steatohepatitis (MASH) by enhancing mitochondrial metabolic function. However, its efficacy at preventing the development of HCC has not been assessed fully. METHODS: l-carnitine (2 g/d) was administered to 11 patients with MASH for 10 weeks, and blood liver function tests were performed. Five patients received a serial liver biopsy, and liver histology and hepatic gene expression were evaluated using this tissue. An atherogenic plus high-fat diet MASH mouse model received long-term l-carnitine administration, and liver histology and liver tumor development were evaluated. RESULTS: Ten-week l-carnitine administration significantly improved serum alanine transaminase and aspartate transaminase levels along with a histological improvement in the NAFLD activity score, while steatosis and fibrosis were not improved. Gene expression profiling revealed a significant improvement in the inflammation and profibrotic gene signature as well as the recovery of lipid metabolism. Long-term l-carnitine administration to atherogenic plus high-fat diet MASH mice substantially improved liver histology (inflammation, steatosis, and fibrosis) and significantly reduced the incidence of liver tumors. l-carnitine directly reduced the expression of the MASH-associated and stress-induced transcriptional factor early growth response 1. Early growth response 1 activated the promoter activity of neural precursor cell expressed, developmentally downregulated protein 9 (NEDD9), an oncogenic protein. Thus, l-carnitine reduced the activation of the NEDD9, focal adhesion kinase 1, and AKT oncogenic signaling pathway. CONCLUSIONS: Short-term l-carnitine administration ameliorated MASH through its anti-inflammatory effects. Long-term l-carnitine administration potentially improved the steatosis and fibrosis of MASH and may eventually reduce the risk of HCC.

Nucleos(t)ide analogs for hepatitis B virus infection differentially regulate the growth factor signaling in hepatocytes.

BACKGROUND: Recent clinical studies have suggested that the risk of developing HCC might be lower in patients with chronic hepatitis B receiving tenofovir disoproxil fumarate than in patients receiving entecavir, although there is no difference in biochemical and virological remission between the 2 drugs. METHODS: The effects of nucleoside analogs (NsAs; lamivudine and entecavir) or nucleotide analogs (NtAs; adefovir disoproxil, tenofovir disoproxil fumarate, and tenofovir alafenamide) on cell growth and the expression of growth signaling molecules in hepatoma cell lines and PXB cells were investigated in vitro. The tumor inhibitory effects of NsAs or NtAs were evaluated using a mouse xenograft model, and protein phosphorylation profiles were investigated. The binding of NsAs or NtAs to the insulin receptor (INSR) was investigated by thermal shift assays. RESULTS: NtAs, but not NsAs, showed direct growth inhibitory effects on hepatoma cell lines in vitro and a mouse model in vivo. A phosphoprotein array revealed that INSR signaling was impaired and the levels of phosphorylated (p)-INSRß and downstream molecules phosphorylated (p)-IRS1, p-AKT, p-Gab1, and p-SHP2 were substantially reduced by NtAs. In addition, p-epidermal growth factor receptor and p-AKT levels were substantially reduced by NtAs. Similar findings were also found in PXB cells and nontumor lesions of liver tissues from patients with chronic hepatitis B. Prodrug NtAs, but not their metabolites (adefovir, adefovir monophosphate, adefovir diphosphate, tenofovir, tenofovir monophosphate, and tenofovir diphosphate), had such effects. A thermal shift assay showed the binding of NtAs to INSRß. CONCLUSIONS: NtAs (adefovir disoproxil, tenofovir disoproxil fumarate, and tenofovir alafenamide), which are adenine derivative acyclic nucleotide analogs, potentially bind to the ATP-binding site of growth factor receptors and inhibit their autophosphorylation, which might reduce the risk of HCC in patients with chronic hepatitis B.

Photodynamic therapy with talaporfin sodium for endoscopically unresectable gastric cancer using a novel simultaneous light-emitting method.

We describe a case of gastric cancer treated by photodynamic therapy (PDT) with talaporfin sodium using a novel simultaneous light-emitting method. An 82-year-old man was diagnosed with gastric cancer near the cardia with suspected deep submucosal invasion. Surgical resection was deemed high-risk owing to an underlying pulmonary disease. After ruling out endoscopic procedures due to intense fibrosis resulting from the scarring, PDT with talaporfin sodium was chosen. PDT was successfully conducted using an endoscope with simultaneous light emission. The patient experienced a complete response to the treatment and showed no signs of recurrence during follow-up. This case highlights the potential of PDT with talaporfin sodium as a viable alternative for challenging cases, particularly in patients unsuitable for surgery and endoscopic resection. Furthermore, the novel simultaneous light-emitting method may improve the efficiency of the procedure. This case demonstrates the potential of PDT in gastric cancer treatment, especially for high-risk patients.

Successful second-line treatment with cabozantinib for hepatocellular carcinoma harboring cytoplasmic mesenchymal-epithelial transition factor amplification.

A 72-year-old man with metastatic hepatocellular carcinoma previously received first-line systemic therapy with atezolizumab plus bevacizumab. His disease was judged to be progressing 5 months after treatment initiation. Comprehensive genomic profiling revealed cytoplasmic mesenchymal-epithelial transition factor amplification. On the basis of an expert panel's recommendation, he received cabozantinib as second-line therapy. The tumors shrank markedly and continued to shrink 6 months after treatment. Comprehensive genomic profiling could provide useful information for selecting effective second-line treatments for patients with hepatocellular carcinoma after first-line immunotherapy.

Post-allogeneic Hematopoietic Stem Cell Transplantation Portal Hypertension Not Associated with Liver Cirrhosis, Veno-occlusive Disease, or Graft-versus-host Disease: A Case Report.

We herein report a rare case of idiopathic portal hypertension (IPH)-like disease that developed after allogeneic hematopoietic stem cell transplantation (allo-HSCT). A 53-year-old woman who underwent allo-HSCT for acute myeloid leukemia showed portal hypertension with radiological and histopathological findings consistent with IPH, distinct from veno-occlusive disease (VOD) and graft-versus-host disease (GVHD) of the liver. This case highlights the importance of considering IPH-like disease as a potential cause of portal hypertension after allo-HSCT. Awareness of this complication can aid in the early diagnosis and appropriate management of patients post allo-HSCT.

Aldo-keto reductase family 1 member B10 is regulated by nucleos(t)ide analogues for chronic hepatitis B.

The number of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) patients persists even under nucleos(t)ide analogues (NAs) treatment. Aldo-keto reductase family 1 member B10 (AKR1B10) expression has been reported in advanced chronic liver diseases as well as cancer tissues. We observed an association between related to HCC incidence and serum AKR1B10 by analyzing patients under treatment with NAs. Serum AKR1B10 levels measured by ELISA were higher in HCC cases under NA treatment compared with non-HCC cases and were associated with lamivudine- and adefovir pivoxil-, but not entecavir- or tenofovir alafenamide-treated cases. The latter drugs did not increase AKR1B10 values even in HCC cases, suggesting that they influence the reduction of AKR1B10 in any cases. This analysis was supported by in-vitro examination, which showed reduced AKR1B10 expression by entecavir and tenofovir via immunofluorescence staining. In conclusion there was a relationship between HBV-related HCC incidence and AKR1B10 under nucleos(t)ide analogues, especially in the use of lamivudine and adefovir pivoxil, but entecavir and tenofovir had suppressive effects of AKR1B10.

Plasma Antithrombin III Levels Can Be a Prognostic Factor in Liver Cirrhosis Patients with Portal Vein Thrombosis.

Liver function influences the plasma antithrombin (AT)-III levels. AT-III is beneficial for patients with portal vein thrombosis (PVT) and low plasma AT-III levels. However, whether these levels affect prognosis in patients with cirrhosis-associated PVT remains unknown. This retrospective study involved 75 patients with cirrhosis and PVT treated with danaparoid sodium with or without AT-III. The plasma AT-III level was significantly lower in patients with liver failure-related death than in those with hepatocellular carcinoma (HCC)-related death (p = 0.005), although the Child-Pugh and albumin-bilirubin (ALBI) scores were not significantly different between these two groups. Receiver operating characteristic curve analysis of the plasma AT-III levels showed cutoff values of 54.0% at 5-year survival. Low plasma AT-III levels (<54.0%) were associated with significantly worse prognosis than high levels in both overall survival (p = 0.0013) and survival excluding HCC-related death (p < 0.0001). Low plasma AT-III (<54.0%) was also associated with a significantly worse prognosis among patients with Child-Pugh A/B or ALBI grade 1/2 (p < 0.0001). Multivariate analyses indicated that low plasma AT-III levels (<54.0%) were an independent prognostic factor for poor survival outcome. Low plasma AT-III levels may be associated with mortality, particularly liver failure-related death, independent of liver function.

Identification of a Transmembrane Protein Involved in Shear Stress Signaling and Hepatocarcinogenesis After a Sustained Virological Response to Hepatitis C Virus.

BACKGROUND & AIMS: The risk of hepatocellular carcinoma (HCC) remains after achieving a sustained virological response (SVR) in patients with chronic hepatitis C (CHC). Epigenetic abnormalities might be key regulators in the development of HCC. This study aimed to identify the genes involved in hepatocarcinogenesis after an SVR. METHODS: DNA methylation in liver tissue was compared between 21 CHC patients without HCC and 28 CHC patients with HCC, all of whom had achieved an SVR. Additional comparisons with 23 CHC patients before treatment and 10 normal livers were performed. The characteristics of a newly identified gene were explored in vitro and in vivo. RESULTS: We found that the transmembrane protein no. 164 (TMEM164) gene was demethylated by hepatitis C virus infection and HCC development after achieving an SVR. TMEM164 was expressed mainly in endothelial cells, alpha smooth muscle actin-positive cells, and some capillarized liver sinusoidal endothelial cells. TMEM164 expression was significantly correlated with liver fibrosis and relapse-free survival in HCC patients. TMEM164 was induced by shear stress, interacted with GRP78/BiP, accelerated ATF6 (activating transcription factor 6)-mediated endoplasmic reticulum (ER) stress signaling, and activated interleukin-6/STAT3 (signal transducer and activator of transcription 3) signaling in the TMNK1 liver endothelial cell line. Therefore, we termed TMEM164 "shear stress-induced transmembrane protein associated with ER stress signaling" (SHERMER). SHERMER knockout mice were protected against CCL4-induced liver fibrosis. SHERMER overexpression in TMNK1 cells accelerated HCC growth in a xenograft model. CONCLUSIONS: We identified a new transmembrane protein, SHERMER, in CHC patients with HCC after achieving an SVR. SHERMER was induced by shear stress and accelerated ATF6-mediated ER stress signaling in endothelial cells. Thus, SHERMER is a novel endothelial marker associated with liver fibrosis, hepatocarcinogenesis, and progression of HCC.

Development of performance indicators for hepatitis countermeasures as a tool for the assessment and promotion of liver cancer prevention in Japan.

BACKGROUND: Hepatitis countermeasures are being promoted by governments in Japan. We aimed to develop performance indicators (PIs) to assess the process and outcome of such countermeasures implemented for the prevention of viral hepatitis-related liver cancer at the national and prefectural government levels. METHODS: We developed 19 PIs for hepatitis countermeasures implemented by local governments, covering the morbidity and mortality of liver cancer, hepatitis testing, subsidy programs for examinations and antiviral treatment, and education on hepatitis patient care to healthcare workers. We analyzed the PIs for each prefecture from Fiscal Year (FY) 2018-2020. RESULTS: The morbidity and mortality of liver cancer significantly decreased in the study period. The percentage of municipalities conducting hepatitis screening was already high at 95% in FY2017. The usage rate of government-subsidized screenings did not change. The subsidy usage rate for periodic viral hepatitis examination significantly increased. Meanwhile, the subsidy usage rate for antiviral treatment of hepatitis B increased, whereas that for hepatitis C decreased. The number of certified healthcare workers providing care for hepatitis patients increased significantly, and these workers were efficiently placed at regional core centers, institutions specialized in liver diseases, health care centers, and municipal governments. Liver cancer mortality was positively correlated with hepatitis screening, subsidies for periodic examinations, and the number of hepatitis medical care coordinators but was negatively correlated with subsidies for anti-HCV therapy, suggesting that rigorous countermeasures were implemented in prefectures with high liver cancer mortality. CONCLUSIONS: The developed PIs could be a useful tool for monitoring government efforts and achievements, thereby providing basic data for setting practical goals in liver cancer prevention.

Hepatitis B Virus Utilizes a Retrograde Trafficking Route via the Trans-Golgi Network to Avoid Lysosomal Degradation.

BACKGROUND & AIMS: Hepatitis B virus (HBV) infection is difficult to cure owing to the persistence of covalently closed circular viral DNA (cccDNA). We performed single-cell transcriptome analysis of newly established HBV-positive and HBV-negative hepatocellular carcinoma cell lines and found that dedicator of cytokinesis 11 (DOCK11) was crucially involved in HBV persistence. However, the roles of DOCK11 in the HBV lifecycle have not been clarified. METHODS: The cccDNA levels were measured by Southern blotting and real-time detection polymerase chain reaction in various hepatocytes including PXB cells by using an HBV-infected model. The retrograde trafficking route of HBV capsid was investigated by super-resolution microscopy, proximity ligation assay, and time-lapse analysis. The downstream molecules of DOCK11 and underlying mechanism were examined by liquid chromatography-tandem mass spectrometry, immunoblotting, and enzyme-linked immunosorbent assay. RESULTS: The cccDNA levels were strongly increased by DOCK11 overexpression and repressed by DOCK11 suppression. Interestingly, DOCK11 functionally associated with retrograde trafficking proteins in the trans-Golgi network (TGN), Arf-GAP with GTPase domain, ankyrin repeat, and pleckstrin homology domain-containing protein 2 (AGAP2), and ADP-ribosylation factor 1 (ARF1), together with HBV capsid, to open an alternative retrograde trafficking route for HBV from early endosomes (EEs) to the TGN and then to the endoplasmic reticulum (ER), thereby avoiding lysosomal degradation. Clinically, DOCK11 levels in liver biopsies from patients with chronic hepatitis B were significantly reduced by entecavir treatment, and this reduction correlated with HBV surface antigen levels. CONCLUSIONS: HBV uses a retrograde trafficking route via EEs-TGN-ER for infection that is facilitated by DOCK11 and serves to maintain cccDNA. Therefore, DOCK11 is a potential therapeutic target to prevent persistent HBV infection.

Alterations in Hepatocellular Carcinoma-Specific Immune Responses Following Hepatitis C Virus Elimination by Direct-Acting Antivirals.

Direct-acting antivirals (DAAs) have recently revolutionized the eradication of chronic hepatitis C virus (HCV) infection. However, the effects of DAAs on the development of hepatocellular carcinoma (HCC) remain unknown. Therefore, the present study aimed to investigate immune responses to HCC influenced by DAAs in HCV-infected patients and elucidate the underlying mechanisms. We compared immune responses to 19 different HCC-related tumor-associated antigen (TAA)-derived peptides and host immune cell profiles before and 24 weeks after a treatment with DAAs in 47 HLA-A24-positive patients. The relationships between the different immune responses and phenotypic changes in immune cells were also examined. The treatment with DAAs induced four types of immune responses to TAAs and markedly altered host immune cell profiles. Prominently, reductions in the frequencies of PD-1+CD4+ and PD-1+CD8+ T cells by DAAs were associated with enhanced immune responses to TAAs. The HCV F protein was identified as contributing to the increased frequency of PD-1+ T cells, which may be decreased after eradication by DAAs. DAAs altered the immune responses of patients to HCC by decreasing the frequency of PD-1-expressing CD4+ and CD8+ T cells.

FOXM1 Is a Novel Molecular Target of AFP-Positive Hepatocellular Carcinoma Abrogated by Proteasome Inhibition.

Alpha-fetoprotein (AFP) is an oncofetal protein that is elevated in a subset of hepatocellular carcinoma (HCC) with poor prognosis, but the molecular target activated in AFP-positive HCC remains elusive. Here, we demonstrated that the transcription factor forkhead box M1 (FOXM1) is upregulated in AFP-positive HCC. We found that FOXM1 expression was highly elevated in approximately 40% of HCC cases, and FOXM1-high HCC was associated with high serum AFP levels, a high frequency of microscopic portal vein invasion, and poor prognosis. A transcriptome and pathway analysis revealed the activation of the mitotic cell cycle and the inactivation of mature hepatocyte metabolism function in FOXM1-high HCC. The knockdown of FOXM1 reduced AFP expression and induced G2/M cell cycle arrest. We further identified that the proteasome inhibitor carfilzomib attenuated FOXM1 protein expression and suppressed cell proliferation in AFP-positive HCC cells. Carfilzomib in combination with vascular endothelial growth factor receptor 2 (VEGFR2) blockade significantly prolonged survival by suppressing AFP-positive HCC growth in a subcutaneous tumor xenotransplantation model. These data indicated that FOXM1 plays a pivotal role in the proliferation of AFP-positive liver cancer cells. Carfilzomib can effectively inhibit FOXM1 expression to inhibit tumor growth and could be a novel therapeutic option in patients with AFP-positive HCC who receive anti-VEGFR2 antibodies.

Leukocyte cell-derived chemotaxin 2 is an antiviral regulator acting through the proto-oncogene MET.

Retinoic acid-inducible gene (RIG)-I is an essential innate immune sensor that recognises pathogen RNAs and induces interferon (IFN) production. However, little is known about how host proteins regulate RIG-I activation. Here, we show that leukocyte cell-derived chemotaxin 2 (LECT2), a hepatokine and ligand of the MET receptor tyrosine kinase is an antiviral regulator that promotes the RIG-I-mediated innate immune response. Upon binding to MET, LECT2 induces the recruitment of the phosphatase PTP4A1 to MET and facilitates the dissociation and dephosphorylation of phosphorylated SHP2 from MET, thereby protecting RIG-I from SHP2/c-Cbl-mediated degradation. In vivo, LECT2 overexpression enhances RIG-I-dependent IFN production and inhibits lymphocytic choriomeningitis virus (LCMV) replication in the liver, whereas these changes are reversed in LECT2 knockout mice. Forced suppression of MET abolishes IFN production and antiviral activity in vitro and in vivo. Interestingly, hepatocyte growth factor (HGF), an original MET ligand, inhibits LECT2-mediated anti-viral signalling; conversely, LECT2-MET signalling competes with HGF-MET signalling. Our findings reveal previously unrecognized crosstalk between MET-mediated proliferation and innate immunity and suggest that targeting LECT2 may have therapeutic value in infectious diseases and cancer.

Upregulation of the Long Noncoding RNA HULC by Hepatitis C Virus and Its Regulation of Viral Replication.

BACKGROUND: Many long noncoding RNAs (lncRNAs) have important roles in biological processes. The lncRNA HULC was found to be upregulated in human hepatoma tissues. HULC is thought to be involved in multiple steps of hepatoma development and progression; however, the relationship between HULC and hepatitis C virus (HCV) infection, which is a leading cause of hepatoma, remains unclear. METHODS: We examined the effect of HCV replication on HULC expression and the underlying mechanism using cell culture systems. Subsequently, we tested the effect of HULC suppression and overexpression on HCV replication. Finally, we examined the impact of HCV eradication on HULC expression using human liver tissue and blood samples. RESULTS: HCV replication increased HULC expression in cell cultures. A promoter assay showed that an HCV nonstructural protein, NS5A, increased HULC transcription. HULC suppression inhibited HCV replication; conversely, its overexpression enhanced HCV replication. These effects on HCV replication seemed to occur by the modification of HCV translation. Measurements from human liver and blood samples showed that HCV eradication significantly reduced HULC levels in the liver and blood. CONCLUSIONS: HCV infection increases HULC expression in vitro and in vivo. HULC modulates HCV replication through an HCV internal ribosome entry site-directed translation step.

Decline in serum albumin concentration is a predictor of serious events in nonalcoholic fatty liver disease.

ABSTRACT: Nonalcoholic fatty liver disease (NAFLD) is associated with metabolic syndrome, which includes diabetes mellitus and hyperlipidemia. A fraction of NAFLD patients develop nonalcoholic steatohepatitis, leading to cirrhosis associated with various serious complications, including hepatocellular carcinoma, gastroesophageal varices, cardiovascular events, and other organ malignancy. Although the incidence of chronic viral hepatitis with associated complications has gradually decreased as highly effective antiviral therapies have been established, the number of patients with steatohepatitis has been increasing.This retrospective study examined data of 229 patients from 22 hospitals in our region. We examined 155 cases of chronological data and assessed the development of liver fibrosis and evaluated hepatic reserve-related markers such as platelet count, FIB-4 index, prothrombin time, and serum albumin concentration. We analyzed the relationship of these chronological changes and the incidence of NAFLD related serious complications.Data related to liver fibrosis progression, albumin, and prothrombin time were significantly associated with the occurrence of serious complications associated with cirrhosis. We compared 22 event and 133 nonevent cases of chronological changes in the data per year and found that serum albumin concentration was significantly lower in the group that developed serious complications (event cases: -0.21 g/dL/year, nonevent cases: -0.04 g/dL/year (P < .001)). This albumin decline was only the associated factor with the event incidence by multivariate analysis (P < .01).Annual decline in serum albumin concentration in patients with NAFLD is associated with serious events from the outcome of multicenter retrospective study. This highlights its potential utility as a surrogate marker to assess the efficacy of prediction of NAFLD related serious events.

Establishment of liver tumor cell lines from atherogenic and high fat diet fed hepatitis C virus transgenic mice.

A syngeneic mouse model bearing a transplanted tumor is indispensable for the evaluation of the efficacy of immune checkpoint inhibitors (ICIs). However, few syngeneic mouse models of liver cancer are available. We established liver tumor cell lines (MHCF1 and MHCF5) from hepatitis C virus transgenic mice fed an atherogenic high-fat diet. MHCF1 and MHCF5 were successfully transplanted into the subcutaneous space of syngeneic C57BL/6 mice, in addition, they efficiently developed orthotopic tumors in the liver of syngeneic C57BL/6 mice. MHCF5 grew rapidly and showed a more malignant phenotype compared with MHCF1. Histologically, MHCF1-derived tumors were a combined type of hepatocellular carcinoma and MHCF5-derived tumors showed a sarcomatous morphology. Interestingly, MHCF1 and MHCF5 showed different sensitivity against an anti-PD1 antibody and MHCF5-derived tumors were resistant to this antibody. CD8 T cells infiltrated the MHCF1-derived tumors, but no CD8 T cells were found within the MHCF5-derived tumors. Gene expression profiling and whole-exon sequencing revealed that MHCF5 displayed the features of an activated cancer stem cell-like signature of sonic hedgehog and Wnt signaling. Therefore, these cell lines could be useful for the identification of new biomarkers and molecular mechanisms of ICI resistance and the development of new drugs against liver cancer.

BMP9-ID1 signaling promotes EpCAM-positive cancer stem cell properties in hepatocellular carcinoma.

The malignant nature of hepatocellular carcinoma (HCC) is closely related to the presence of cancer stem cells (CSCs). Bone morphologic protein 9 (BMP9), a member of the transforming growth factor-beta (TGF-ß) superfamily, was recently reported to be involved in liver diseases including cancer. We aimed to elucidate the role of BMP9 signaling in HCC-CSC properties and to assess the therapeutic effect of BMP receptor inhibitors in HCC. We have identified that high BMP9 expression in tumor tissues or serum from patients with HCC leads to poorer outcome. BMP9 promoted CSC properties in epithelial cell adhesion molecule (EpCAM)-positive HCC subtype via enhancing inhibitor of DNA-binding protein 1 (ID1) expression in vitro. Additionally, ID1 knockdown significantly repressed BMP9-promoted HCC-CSC properties by suppressing Wnt/ß-catenin signaling. Interestingly, cells treated with BMP receptor inhibitors K02288 and LDN-212854 blocked HCC-CSC activation by inhibiting BMP9-ID1 signaling, in contrast to cells treated with the TGF-ß receptor inhibitor galunisertib. Treatment with LDN-212854 suppressed HCC tumor growth by repressing ID1 and EpCAM in vivo. Our study demonstrates the pivotal role of BMP9-ID1 signaling in promoting HCC-CSC properties and the therapeutic potential of BMP receptor inhibitors in treating EpCAM-positive HCC. Therefore, targeting BMP9-ID1 signaling could offer novel therapeutic options for patients with malignant HCC.

Serum Laminin γ2 Monomer as a Diagnostic and Predictive Biomarker for Hepatocellular Carcinoma.

BACKGROUNDS AND AIMS: Structural dynamics of basement membrane components are still to be elucidated in the process of hepatocarcinogenesis. We evaluated the characteristics of HCC expressing laminin γ2 monomer (LG2m), a basement membrane component not detected in normal tissues, for HCC diagnosis. We further determined whether elevated serum LG2m is a risk factor for HCC development in patients with chronic hepatitis C (CHC). APPROACH AND RESULTS: In HCC cell lines, LG2m was expressed in alpha-fetoprotein (AFP)-negative, CD90-positive cells characterized by highly metastatic natures. Using 14 cell lines and 258 HCC microarray data, we identified that LG2m gene signature was associated with Hoshida's S1/Boyault's G3 molecular subclasses with poor prognosis, which could not be recognized by AFP. Serum LG2m was assessed in 24 healthy donors, 133 chronic liver disease patients, and 142 HCC patients, and sensitivity and specificity of LG2m testing for HCC diagnosis were 62.9% and 70.5%, respectively (cutoff, 30 pg/mL). We evaluated the consequence of LG2m elevation in two independent HCC cohorts (n = 47 and n = 81), and LG2m-high HCC showed poor prognosis with later development of distant organ metastasis (cutoff, 60 pg/mL). LG2m was slightly elevated in a subset of CHC patients, and Kaplan-Meier analysis indicated a high incidence of HCC (n = 70). For validation, we enrolled 399 CHC patients with sustained virological response (SVR) as a multicenter, prospective study, and serum LG2m elevation correlated with a high incidence of HCC in the CHC patients with SVR (P < 0.0001). CONCLUSIONS: LG2m is a predictive biomarker for the development of metastatic HCC. Elevated serum LG2m is an HCC risk in CHC patients who have achieved SVR.

Safety and efficacy of sorafenib followed by regorafenib or lenvatinib in patients with hepatocellular carcinoma.

AIM: Sequential administration of sorafenib followed by regorafenib or lenvatinib is effective against advanced hepatocellular carcinoma (HCC). In this study, we compared the safety profiles and anti-tumor effects of sequential sorafenib and regorafenib or lenvatinib therapy in patients with HCC. METHODS: We investigated adverse events, treatment responses and dose intensities in patients with HCC who were consecutively treated with sorafenib followed by regorafenib or lenvatinib at the individual level. RESULTS: Each group included 20 patients. The safety profiles of regorafenib and sorafenib were similar. The severity of hypophosphatemia, palmar-plantar erythrodysesthesia syndrome, and decreased neutrophil counts associated with regorafenib or sorafenib was similar in 12 patients. Conversely, the incidences and grades of adverse events differed between sorafenib and lenvatinib treatment. The anti-tumor effects of regorafenib and lenvatinib compared with sorafenib were significantly different for each patient. The response to treatment and progression-free survival were comparable for regorafenib and lenvatinib. The median relative dose intensities during the first 56 days of regorafenib and lenvatinib treatment were 83.6 and 80.0%, respectively. CONCLUSIONS: Similar adverse events were experienced by patients during consecutive treatment with sorafenib and regorafenib, which was not observed during treatment with sorafenib and lenvatinib. The obtained safety profile of sorafenib provided meaningful insights for selecting sequential therapy for patients with advanced HCC.

Extended interaction networks with HCV protease NS3-4A substrates explain the lack of adaptive capability against protease inhibitors.

Inhibitors against the NS3-4A protease of hepatitis C virus (HCV) have proven to be useful drugs in the treatment of HCV infection. Although variants have been identified with mutations that confer resistance to these inhibitors, the mutations do not restore replicative fitness and no secondary mutations that rescue fitness have been found. To gain insight into the molecular mechanisms underlying the lack of fitness compensation, we screened known resistance mutations in infectious HCV cell culture with different genomic backgrounds. We observed that the Q41R mutation of NS3-4A efficiently rescues the replicative fitness in cell culture for virus variants containing mutations at NS3-Asp168 To understand how the Q41R mutation rescues activity, we performed protease activity assays complemented by molecular dynamics simulations, which showed that protease-peptide interactions far outside the targeted peptide cleavage sites mediate substrate recognition by NS3-4A and support protease cleavage kinetics. These interactions shed new light on the mechanisms by which NS3-4A cleaves its substrates, viral polyproteins and a prime cellular antiviral adaptor protein, the mitochondrial antiviral signaling protein MAVS. Peptide binding is mediated by an extended hydrogen-bond network in NS3-4A that was effectively optimized for protease-MAVS binding in Asp168 variants with rescued replicative fitness from NS3-Q41R. In the protease harboring NS3-Q41R, the N-terminal cleavage products of MAVS retained high affinity to the active site, rendering the protease susceptible for potential product inhibition. Our findings reveal delicately balanced protease-peptide interactions in viral replication and immune escape that likely restrict the protease adaptive capability and narrow the virus evolutionary space.