A20 in hepatic stellate cells suppresses chronic hepatitis by inhibiting DCLK1-JNK pathway-dependent chemokines.

Hepatic stellate cells (HSCs) are responsible for liver fibrosis accompanied by its activation into myofibroblasts and the abundant production of extracellular matrix. However, the HSC contribution to progression of liver inflammation has been less known. We aimed to elucidate the mechanism in HSCs underlying the inflammatory response and the function of tumor necrosis factor α-related protein A20 (TNFAIP3). We established A20 conditional knockout (KO) mice crossing Twist2-Cre and A20 floxed mice. Using these mice, the effect of A20 was analyzed in mouse liver and HSCs. The human HSC line LX-2 was also used to examine the role and underlying molecular mechanism of A20. In this KO model, A20 was deficient in >80% of HSCs. Spontaneous inflammation with mild fibrosis was found in the liver of the mouse model without any exogenous agents, suggesting that A20 in HSCs suppresses chronic hepatitis. Comprehensive RNA sequence analysis revealed that A20-deficient HSCs exhibited an inflammatory phenotype and abnormally expressed chemokines. A20 suppressed JNK pathway activation in HSCs. Loss of A20 function in LX-2 cells also induced excessive chemokine expression, mimicking A20-deficient HSCs. A20 overexpression suppressed chemokine expression in LX-2. In addition, we identified DCLK1 in the genes regulated by A20. DCLK1 activated the JNK pathway and upregulates chemokine expression. DCLK1 inhibition significantly decreased chemokine induction by A20-silencing, suggesting that A20 controlled chemokine expression in HSCs via the DCLK1-JNK pathway. In conclusion, A20 suppresses chemokine induction dependent on the DCLK1-JNK signaling pathway. These findings demonstrate the therapeutic potential of A20 and the DCLK1-JNK pathway for the regulation of inflammation in chronic hepatitis.

High serum gamma-glutamyltransferase level after hepatitis C virus elimination is a risk factor for the development of hepatocellular carcinoma.

AIM: Gamma-glutamyltransferase (GGT) is known as an oxidative stress marker, induced by alcohol consumption and metabolic disorders, and is reported as a predictor of hepatocellular carcinoma (HCC) development after hepatitis C virus (HCV) elimination. However, it is not clear whether GGT serves simply as a surrogate marker for overlapping metabolic diseases or reflects HCV-specific carcinogenicity. We investigated the association between GGT and hepatocarcinogenesis after achieving a sustained viral response (SVR), accounting for drinking habits or diabetes, and examined predisposing factors associated with GGT levels after SVR. METHODS: This is a prospective, multicenter, and observational study using the database of 1001 patients after HCV eradication with direct-acting antiviral agents. The association of GGT at SVR with cumulative HCC development was examined in a multivariate analysis using Cox proportional hazard models after adjustment for covariates including alcohol and diabetes. The association between oxidative stress markers or genetic factors and GGT levels was analyzed. RESULTS: High GGT levels at SVR were associated with HCC development (HR] 2.38, 95% CI 1.10-5.17). This association was also significant when restricted to patients without alcohol consumption or diabetes (HR 8.38, 95% CI 2.87-24.47). GGT levels were correlated with serum growth differentiation factor 15 levels, a marker of mitochondrial dysfunction. Single-nucleotide polymorphisms of ZNF827 and GDF15 were associated with high GGT levels. CONCLUSIONS: High GGT levels at SVR were associated with HCC development after accounting for alcohol consumption and diabetes. GGT levels are influenced by genetic predisposition and may reflect mitochondrial dysfunction after HCV eradication.

Analysis of prognosis and background liver disease in non-advanced hepatocellular carcinoma in two decades.

BACKGROUND/AIM: Antiviral hepatitis and systemic therapies for hepatocellular carcinoma (HCC) remarkably progressed in the recent 10 years. This study aimed to reveal the actual transition and changes in the prognosis and background liver disease in non-advanced HCC in the past 20 years. METHODS: This retrospectively recruited 566 patients who were diagnosed with non-advanced HCC from February 2002 to February 2022. The prognosis was analyzed by subdividing according to the diagnosis date (period I: February 2002-April 2009 and period Ⅱ: May 2009-February 2022). RESULTS: Patients in period II (n = 351) were significantly older, with lower albumin-bilirubin (ALBI) scores and alpha-fetoprotein (AFP) and more anti-viral therapy, systemic therapy, and hepatic arterial infusion chemotherapy as compared with those in period I (n = 215). The etiology ratio of the background liver disease revealed decreased hepatitis C virus from 70.6% to 49.0% and increased non-B, non-C from 17.7% to 39.9% from periods I to Ⅱ. The multivariate analysis revealed older age and higher ALBI score in Barcelona Clinic Liver Cancer (BCLC) 0/A stage, AFP of >20 ng/mL, and higher ALBI score in BCLC B stage as independent prognosis factors. Fine-Gray competing risk model analysis revealed that liver-related deaths significantly decreased in period II as compared to period I, especially for BCLC stage 0/A (HR: 0.656; 95%CI: 0.442-0.972, P = 0.036). CONCLUSION: The characteristics of patients with non-advanced HCC have changed over time. Appropriate background liver management led to better liver-related prognoses in BCLC 0/A.

Prognostic significance of C-reactive protein in unresectable hepatocellular carcinoma treated with atezolizumab and bevacizumab.

AIM: C-reactive protein (CRP) is both an inflammatory and prognostic marker in various cancers. This study aimed to elucidate the characteristics of CRP and the prognostic factors in patients who were administered with atezolizumab plus bevacizumab (ATZ + BEV) for unresectable hepatocellular carcinoma (HCC). METHODS: A total of 213 patients who received ATZ + BEV for HCC from November 2020 to March 2023 at 15 hospitals were enrolled in this retrospective study. The prognosis was analyzed by subdividing the patients based on baseline characteristics, radiologic response, and treatment lines. Accuracy of survival prediction was assessed using CRP, alpha fetoprotein (AFP), C-reactive protein and alpha fetoprotein in immunotherapy (CRAFITY), and Glasgow Prognostic Score. RESULTS: Compared with patients with baseline CRP <1 mg/dL, those with baseline CRP ≥1 mg/dL (n = 45) had a significantly higher baseline albumin-bilirubin score and AFP levels, significantly lower disease control rate (62.2%), and significantly shorter median overall survival (hazards ratios 2.292; 95% confidence interval 1.313-5.107; log-rank test, p < 0.001). Multivariate analysis identified CRP ≥1 mg/dL, AFP ≥100 ng/mL, and modified albumin-bilirubin grade as the significant prognostic factors. The baseline CRP, AFP, CRAFITY, and Glasgow Prognostic Score demonstrated higher discrimination for 1-year survival prediction after first-line ATZ + BEV administration, compared with beyond second line, with area under the receiver operating characteristic curves of 0.759, 0.761, 0.805, and 0.717, respectively. CONCLUSIONS: CRP was a significant biomarker in patients treated with ATZ + BEV for HCC. Elevated CRP levels may indicate aggressive cancer progression and potential resistance to ATZ + BEV therapy.

Factors associated with liver injury and prognosis in advanced cancer patients treated with immune checkpoint inhibitors.

AIM: The use of immune checkpoint inhibitors (ICIs) has increased remarkably, and immune-related adverse events (irAEs) have also increased. This study aimed to identify factors associated with immune-related liver injury (irLI), and the relationship between the grades of irLI and overall survival (OS) in patients treated with ICIs. METHODS: A total of 571 patients who had been treated for advanced malignancies with ICIs between January 2015 and March 2022 were retrospectively recruited. The presence of liver injury was determined by the aspartate aminotransferase and alanine aminotransferase elevation. The irLI grading was based on Common Terminology Criteria for Adverse Events version 5.0. RESULTS: A total of 50 (8.8%) patients had grade ≥2 irLI and 24 (4.2%) had grade ≥3 irLI. Treatment with anti-cytotoxic T-lymphocyte-associated protein-4 agents and baseline grade 1 aspartate aminotransferase/alanine aminotransferase elevation were independent predictive factors of grade ≥2 irLI. Treatment with anti-cytotoxic T-lymphocyte-associated protein-4 was the only independent predictive factor of grade ≥3 irLI. The median OS for patients who experienced any irAEs was significantly longer than of those without irAEs (hazard ratio 0.503, 95% CI 0.398-0.636, p < 0.001). The median OS in patients with grade ≥2 irLI was significantly longer (HR 0.570, 95% CI 0.387-0.838, p = 0.022). There was no significant difference between the median OS in patients with grade ≥3 irLI and the others (p = 0.11). CONCLUSION: The incidence of irLI was significantly higher in patients treated with anti-cytotoxic T-lymphocyte-associated protein-4 agents. Even in patients with pre-existing grade 1 aspartate aminotransferase/alanine aminotransferase elevation, appropriate follow-up and control of the irLI can improve the prognosis.

Impact of eradication of hepatitis C virus on liver-related and -unrelated diseases: morbidity and mortality of chronic hepatitis C after SVR.

Hepatitis C virus infection is characterized by chronic liver inflammation and fibrogenesis, leading to end-stage liver failure and hepatocellular carcinoma over the course of 20 to 30 years. It seems not only the chronicity of hepatitis C but also the presence of the virus in non-hepatic tissues creates a favorable environment for the potential development of pathogenic impacts on extrahepatic systems and organs. Numerous extra-hepatic manifestations have been reported in association with HCV infection, all of which can substantially affect morbidity, mortality, and quality of life. With the recent development of DAAs, antiviral treatment can cure almost all patients with HCV infection, even those intolerant of or unresponsive to IFN treatment, and several large multicenter studies have confirmed the association of DAA-induced SVR with reductions in liver-related and liver-unrelated complications, such as cardiovascular events, end stage renal disease, and so on. Because, in addition to liver-related diseases, extrahepatic lesions are threatening for patients, it is important to eradicate the virus before these progress and affect life prognosis; in other words, patients should be treated before reaching the point of no return. Tailored surveillance with biomarkers such as M2BPGi and Ang-2, which can be used to identify patients with an elevated risk of EHM, and early prevention or treatment for these patients could improve the morbidity, mortality and QOL. Advancement of both basic and clinical research in this field including the development of more precise biomarkers is highly anticipated.

Bioassay-guided Fractionation of Clove Buds Extract Identifies Eugenol as Potent Melanogenic Inducer in Melanoma Cells.

Clove, a dried flower buds of Syzygium aromaticum, is used in traditional medicine, for culinary purposes, and in essential oil production. In our preliminary screening of crude drugs used in Japanese Kampo formulas, a methanol (MeOH) extract of clove buds was found to exhibit a melanin induction. To date, the effects of clove buds or their constituents on the activation of melanogenesis remain unclear. Thus, this study aimed to isolate active compounds from the MeOH extract of clove buds associated with melanin synthesis in melanoma cells and to investigate the molecular mechanism involved. The MeOH extract of clove buds increased melanin content in murine B16-F1 melanoma cells. To identify the active compounds responsible for melanin induction, the MeOH extract was suspended in water and successively partitioned using hexane, ethyl acetate (EtOAc), and n-butanol (n-BuOH). Comparative analysis revealed that the EtOAc fraction induced melanin synthesis. Bioassay-guided separation of the EtOAc fraction isolated three compounds including eugenol. The analysis of structure-activity relationships of eugenol and structurally related compounds indicated that eugenol was the most potent melanin inducer among the 11 compounds, and that a hydroxyl group at C-1 and a methoxy group at C-2 may contribute to melanin induction. Eugenol induced melanin synthesis in human HMV-II melanoma cells as well as in B16-F1 cells. Further analysis indicated that eugenol may invoke intracellular tyrosinase activity and expression of tyrosinase, tyrosinaserelated protein (TRP)-1, TRP-2, and microphthalmia-associated transcription factor (MITF). These results suggest that eugenol enhances melanin synthesis by upregulating the expression of MITF and subsequent expression of melanogenic enzymes, and that it may be a potent therapeutic agent for hypopigmentation.

[A curatively resectable case of cholangiocarcinoma 52 years after cholecystoduodenostomy for biliary atresia].

A 52-year-old female had cholecystoduodenostomy for biliary atresia of type I cyst at 120 days of age. The patient's surgery recovery was uneventful;however, the patient had recurring cholangitis at the age of 27. The patient had high hepatobiliary enzymes in the outpatient clinic and was diagnosed with cholangitis. In general, the Kasai method is the mainstream for biliary atresia, since it has a much-reduced incidence of both early and late postoperative problems. However, this patient had biliary atresia of type I cyst and had undergone cholecystoduodenostomy. We suspected that the obstructive cholangitis was caused by the relatively wide anastomosis opening into the duodenal bulb, where the stomach contents pass through the most, and the poor clearance owing to the convoluted cystic duct;therefore, we chose to place a stent endoscopically. However, to our surprise, Class V was detected in the bile cytology performed as a precaution. Although no tumor was seen on imaging such as contrast-enhanced CT, EUS, and PET/CT, mapping biopsy results showed the presence of cancer at the bifurcation of the cystic duct. The patient had cholangiocarcinoma confined to the extrahepatic bile ducts only;thus, extrahepatic bile duct resection was conducted. The patient was discovered to have biliary intraepithelial neoplasia-3, and the tumor was entirely respectable. The patient had a good postoperative course, with normalization of liver function and no recurrence of cholangitis. In this case, cholangiocarcinoma was detected at an early stage by cytological examination performed as a precaution during endoscopic therapy for recurrent cholangitis. In addition to the fact that the long-term pathogenesis of biliary atresia is still unknown, it is important to note the presence of malignancy, which has the greatest effect on the patient prognosis, considering that the course of the disease varies depending on the operation carried out. Because cholecystoduodenostomy for biliary atresia is a rare approach, and there has been no previous report of related cholangiocarcinoma, we report this case for the benefit of gastroenterologists who may encounter similar cases in the future.

Hepatocellular carcinoma recurrence after direct-acting antiviral therapy: an individual patient data meta-analysis.

OBJECTIVE: The benefit of direct-acting antivirals (DAAs) against HCV following successful treatment of hepatocellular carcinoma (HCC) remains controversial. This meta-analysis of individual patient data assessed HCC recurrence risk following DAA administration. DESIGN: We pooled the data of 977 consecutive patients from 21 studies of HCV-related cirrhosis and HCC, who achieved complete radiological response after surgical/locoregional treatments and received DAAs (DAA group). Recurrence or death risk was expressed as HCC recurrence or death per 100 person-years (100PY). Propensity score-matched patients from the ITA.LI.CA. cohort (n=328) served as DAA-unexposed controls (no-DAA group). Risk factors for HCC recurrence were identified using random-effects Poisson. RESULTS: Recurrence rate and death risk per 100PY in DAA-treated patients were 20 (95% CI 13.9 to 29.8, I2=74.6%) and 5.7 (2.5 to 15.3, I2=54.3), respectively. Predictive factors for recurrence were alpha-fetoprotein logarithm (relative risk (RR)=1.11, 95% CI 1.03 to 1.19; p=0.01, per 1 log of ng/mL), HCC recurrence history pre-DAA initiation (RR=1.11, 95% CI 1.07 to 1.16; p<0.001), performance status (2 vs 0, RR=4.35, 95% CI 1.54 to 11.11; 2 vs 1, RR=3.7, 95% CI 1.3 to 11.11; p=0.01) and tumour burden pre-HCC treatment (multifocal vs solitary nodule, RR=1.75, 95% CI 1.25 to 2.43; p<0.001). No significant difference was observed in RR between the DAA-exposed and DAA-unexposed groups in propensity score-matched patients (RR=0.64, 95% CI 0.37 to 1.1; p=0.1). CONCLUSION: Effects of DAA exposure on HCC recurrence risk remain inconclusive. Active clinical and radiological follow-up of patients with HCC after HCV eradication with DAA is justified.

A mixed methods study on the readiness of dental, medical, and nursing students for interprofessional learning.

BACKGROUND: Interprofessional education (IPE) is crucial in dentistry, medicine, and nursing. However, scant mixed methods studies have compared the IPE outcomes across these disciplines to develop evidence-based IPE. This study explored the differences in the readiness of dental, medical, and nursing students for interprofessional learning before and after IPE workshops and elucidated reasons for this disparity. METHODS: Data were obtained from dental, medical, and nursing students who participated in IPE workshops conducted at Tokyo Medical and Dental University in Japan in 2019 and 2020. The participants filled the validated Japanese version of the Readiness for Interprofessional Learning Scale (RIPLS) before and after attending the workshops (n = 378). Paired t-tests were performed to assess differences between the pre- and post- workshop RIPLS scores. Welch's t-tests were deployed to evaluate interdisciplinary differences in their scores. Qualitative analyses were conducted using an explanatory sequential design with focus group discussions (FGDs) held with 17 dental students to explain the quantitative results. RESULTS: Total RIPLS scores increased significantly for every discipline after the workshops (p < 0.001). Dental students scored significantly lower pre- and post- workshop aggregates than medical and nursing students, respectively (p < 0.001). The FGDs yielded three principal themes in the explanations tendered by dental students on their lower scores: 1) dental students rarely felt the need for interprofessional collaborations, 2) dentists often worked without the need for interprofessional collaborations, and 3) dental students believed their contribution to the workshop was insufficient. CONCLUSIONS: The results revealed divergences in the readiness of dental, medical, and nursing students for interprofessional learning, and the study illuminated possible reasons for these disparities. These outcomes will help develop evidence-based IPE by indicating approaches to place a higher value on interprofessional collaborations in educational environments, ameliorate the awareness of educators, and enhance the workshop facilitation style.

Mac-2 binding protein glycosylation isomer as a novel predictive biomarker for patient survival after hepatitis C virus eradication by DAAs.

BACKGROUND: It is crucial to identify risk factors for life prognosis after hepatitis C virus (HCV) eradication among patients with or without a high risk of liver cancer or complications. METHODS: This is a prospective, multicenter and observational study using the database of 1031 patients after HCV eradication by direct-acting antiviral agents (DAAs) to evaluate the development of hepatocellular carcinoma (HCC) and patients' survival after a sustained virological response (SVR). The Cox proportional hazards regression model was used to estimate hazard ratios associated with HCC development and survival. RESULTS: AFP at SVR was significantly associated with HCC recurrence in the adjusted model. Liver fibrosis, Mac-2 binding protein glycosylation isomer (M2BPGi) at SVR and smoking status before treatment were positively associated with the development of HCC and M2BPGi was positively associated with HCC recurrence, although not reaching statistical significance. Among patients without a history of HCC, M2BPGi and estimated glomerular filtration rate (eGFR) at SVR were significantly associated with death after viral eradication [M2BPGi (HR 4.07, 95% CI 1.22, 13.57), eGFR (HR 0.97, 95% CI 0.94, 0.99)]. Strikingly, of 16 patients who died, among participants without a history of HCC, only two died of liver cancer associated with HCV, whereas 11 died of non-HCV- related cancer or cardiovascular diseases. CONCLUSION: M2BPGi at SVR is a potential predictor for patients' survival and a candidate biomarker for detecting individuals who are at greater risk of death due to cancer-related and unrelated to HCV, as well as cardiovascular diseases, after viral eradication.

Associations between demographic factors and the academic trajectories of medical students in Japan.

BACKGROUND: Group-based trajectory modeling is a useful tool for categorizing students' academic trajectories and their determinants. Using insights gained from the analyses, we can identify students at risk for poor academic performance and monitor them to provide support. To date, studies investigating the associations between demographic factors and academic performance trajectories among medical students are scarce. The study objective was to examine the associations between demographic factors and academic performance trajectories in medical students using group-based trajectory modeling. METHODS: Participants included all medical students admitted to Tokyo Medical and Dental University in Japan in 2013 and 2014 (n = 202). Academic performance was evaluated by biannual grade point average (GPA) scores in preclinical years. We used group-based trajectory modeling to categorize students into GPA trajectories. Multinomial logistic regression was used to examine the association between the odds of being in a certain GPA trajectory group and demographic factors such as high school type, high school geographical area, admission test type, high school graduation year, whether the student was a biology major, and sex. RESULTS: Students' GPA trajectories were classified into four trajectory groups as well as another group that consisted of students who withdrew or repeated years. We found that students whose high school geographical area was outside the National Capital Region were 7.2 times more likely to withdraw or repeat years in comparison with students whose school was inside the National Capital Region (OR: 7.21, 95% CI: 1.87, 27.76). In addition, admission test type, high school graduation year, and sex were associated with GPA trajectories. CONCLUSIONS: High school geographical area, admission test type, high school graduation year, and sex were associated with GPA trajectories. These findings provide important insights into identifying students at risk for poor academic performance and strategies for monitoring them to provide adequate and timely support.

Differential effects of individual and school factors on the academic trajectories of Japanese dental students.

OBJECTIVE: Dental students follow different academic performance trajectories in response to increasing study load, based on individual and school factors. Group-based trajectory modeling is useful for clarifying the underlying trajectory patterns of students' academic performance and its determinants. To our knowledge, no studies have used group-based trajectory modeling to examine the effects of individual and school factors on academic performance trajectories in dental students. The objective of this study was to examine the effects of individual and school factors on academic performance trajectories in Japanese dental students using group-based trajectory modeling. METHODS: The analytical sample consists of 103 dental students admitted to Tokyo Medical and Dental University, Tokyo, Japan, in 2013 and 2014. Students' academic performance was assessed by biannual grade point average (GPA) score and GPA in the preclinical phase (second to fourth grade) was used for this study. We used group-based trajectory modeling to categorize students' GPA trajectories into different groups. A multinomial logistic regression model was fit to examine associations between students' individual and school factors, and odds of being assigned to certain GPA groups. RESULTS: GPA trajectories of dental students were classified into 4 different groups. Students' past academic performance in high school was associated with lower GPA trajectories and withdrawal or repeating years. Males were significantly associated with lower GPA trajectories and withdrawal or repeating years, even after adjusting for past academic performance. CONCLUSIONS: Past lower academic performance and being male were positively associated with lower academic performance trajectories in Japanese dental students.

Vasoactive Intestinal Peptide Derived From Liver Mesenchymal Cells Mediates Tight Junction Assembly in Mouse Intrahepatic Bile Ducts.

Formation of intrahepatic bile ducts (IHBDs) proceeds in accordance with their microenvironment. Particularly, mesenchymal cells around portal veins regulate the differentiation and ductular morphogenesis of cholangiocytes in the developing liver; however, further studies are needed to fully understand the arrangement of IHBDs into a continuous hierarchical network. This study aims to clarify the interaction between biliary and liver mesenchymal cells during IHBD formation. To identify candidate factors contributing to this cell-cell interaction, mesenchymal cells were isolated from embryonic day 16.5 matrix metalloproteinase 14 (MMP14)-deficient (knockout [KO]) mice livers, in which IHBD formation is retarded, and compared with those of the wild type (WT). WT mesenchymal cells significantly facilitated the formation of luminal structures comprised of hepatoblast-derived cholangiocytes (cholangiocytic cysts), whereas MMP14-KO mesenchymal cells failed to promote cyst formation. Comprehensive analysis revealed that expression of vasoactive intestinal peptide (VIP) was significantly suppressed in MMP14-KO mesenchymal cells. VIP and VIP receptor 1 (VIPR1) were mainly expressed in periportal mesenchymal cells and cholangiocytic progenitors during IHBD development, respectively, in vivo. VIP/VIPR1 signaling significantly encouraged cholangiocytic cyst formation and up-regulated tight junction protein 1, cystic fibrosis transmembrane conductance regulator, and aquaporin 1, in vitro. VIP antagonist significantly suppressed the tight junction assembly and the up-regulation of ion/water transporters during IHBD development in vivo. In a cholestatic injury model of adult mice, exogenous VIP administration promoted the restoration of damaged tight junctions in bile ducts and improved hyperbilirubinemia. Conclusion: VIP is produced by periportal mesenchymal cells during the perinatal stage. It supports bile duct development by establishing tight junctions and up-regulating ion/water transporters in cholangiocytes. VIP contributes to prompt recovery from cholestatic damage through the establishment of tight junctions in the bile ducts.

Time course alterations of virus sequences and immunoglobulin titers in a chronic hepatitis E patient.

AIM: Hepatitis E virus (HEV) can cause chronic infection in immunocompromised hosts. However, the dynamics of HEV during persistent infection is not well understood. To elucidate time course alterations in virus sequences and anti-HEV antibodies during persistent infection, we analyzed the HEV sequences and titers of anti-HEV antibodies from a chronic hepatitis E patient. METHODS: Serum samples were obtained from a chronic hepatitis E patient under corticosteroid therapy for neurological disease. The titers of anti-HEV antibodies (immunoglobulin A, immunoglobulin M, and immunoglobulin G) in serum samples were detected by enzyme immunoassay. The full or near-full nucleotide sequences of HEV isolated from consecutive serum samples were identified and compared. Phylogenetic analysis was also performed. RESULTS: Alterations of anti-HEV antibodies from a chronic hepatitis E patient were different from those previously reported in acute hepatitis E patients. The virus sequence was unchanged in the period without treatment, but nucleotide mutations were observed after ribavirin treatment was started. In addition, the sequence of this strain had extremely high identity to that isolated from swine liver in Japan. CONCLUSIONS: Virus mutations in HEV emerged after ribavirin treatment was started. Sequence analysis may useful for deciding the treatment strategy for chronic hepatitis E patients who did not eliminate the virus with 3 months of RBV treatment and inferring the origin of the infection. This report provides insights into the chronicity of hepatitis E, and the impact of persistent infection and ribavirin treatment on the emergence of virus mutations.

Comprehensive genetic analysis of cholangiolocellular carcinoma with a coexistent hepatocellular carcinoma-like area and metachronous hepatocellular carcinoma.

AIM: The genetic profile of cholangiolocellular carcinoma (CLC) and its origin in relation to hepatocellular carcinoma (HCC) remain unclear. To elucidate the genetic profile of CLC, a comprehensive analysis of genetic mutations was carried out in a case of CLC with an HCC-like focal area and metachronous HCC. METHOD: Liver tissue was obtained from CLC, a co-existent HCC-like area, and metachronously developed HCC by laser capture microdissection of formalin-fixed paraffin-embedded specimens obtained by hepatectomy. Gene mutational profiles were analyzed comprehensively by next-generation sequencing and digital PCR. Relationships among gene profiles, immunohistochemistry, and clinicopathological findings were investigated. RESULTS: Mutations in EGFR, PTEN, RB1, TP53, and ERBB2 were found in CLC, whereas mutations in KIT, BRAF, PTEN, TP53, and SMAD4 were found in the coexistent HCC-like area. Only the mutation in PTEN has a common Catalogue of Somatic Mutations in Cancer ID in the CLC and coexistent HCC-like area, and is related to the kinase-RAS module. In contrast, no cancer-related mutations were found in the metachronous HCC. No TERT mutations were found in any of the regions by digital PCR. Immunohistochemical staining for p53 was negative in CLC, although ≤10% positive in the coexistent HCC-like area. Immunostaining of C-kit, HER2, PTEN, and SMAD4 were negative. CONCLUSION: The genomic features of CLC and the focal area of an HCC-like region differ, but are related to the kinase-RAS module. The development of carcinogenesis in the CLC and HCC-like areas in this case might differ, following a common PTEN mutation, although alteration of the kinase-RAS module is the most common molecular event in CLC.

Impact of novel NS5A resistance-associated substitutions of hepatitis C virus detected in treatment-experienced patients.

Resistance-associated substitutions (RASs) of hepatitis C virus (HCV) in the NS5A region impair the efficacy of NS5A inhibitors. In this study, we evaluated the characteristics of the novel RASs observed in treatment-failure patients, A92K and a deletion at P32 (P32del), and the susceptibility of viruses with these RASs to various anti-HCV reagents by using JFH-1 based recombinant HCV with NS5A from a genotype 1b Con1 strain (JFH1/5ACon1). We introduced A92K or P32del solely or in combination with Q24K, L28M, R30Q or L31F into the NS5A of JFH1/5ACon1. Viruses harboring R30Q/A92K showed high extracellular core antigens and infectivity titers, whereas the other viruses with RASs showed low replication levels and infectivity titers. All the viruses with A92K or P32del were markedly resistant to ledipasvir, velpatasvir and elbasvir. Interestingly, viruses with R30Q/A92K were more susceptible to grazoprevir than viruses without RAS. All the viruses had a similar susceptibility to ribavirin and sofosbuvir. In conclusion, combination RASs R30Q/A92K enhanced virus production whereas other RASs impaired virus replication. Both A92K and P32del conferred severe resistance even to second generation NS5A inhibitors. However, these viruses were susceptible to grazoprevir, ribavirin and sofosbuvir. Thus, combination regimens with these reagents may eradicate viruses harboring A92K or P32del.

Loss of fibrocystin promotes interleukin-8-dependent proliferation and CTGF production of biliary epithelium.

BACKGROUND & AIMS: Congenital hepatic fibrosis (CHF) is a genetic liver disease resulting in abnormal proliferation of cholangiocytes and progressive hepatic fibrosis. CHF is caused by mutations in the PKHD1 gene and the subsequent dysfunction of the protein it encodes, fibrocystin. However, the underlying molecular mechanism of CHF, which is quite different from liver cirrhosis, remains unclear. This study investigated the molecular mechanism of CHF pathophysiology using a genetically engineered human induced pluripotent stem (iPS) cell model to aid the discovery of novel therapeutic agents for CHF. METHODS: PKHD1-knockout (PKHD1-KO) and heterozygously mutated PKHD1 iPS clones were established by RNA-guided genome editing using the CRISPR/Cas9 system. The iPS clones were differentiated into cholangiocyte-like cells in cysts (cholangiocytic cysts [CCs]) in a 3D-culture system. RESULTS: The CCs were composed of a monolayer of cholangiocyte-like cells. The proliferation of PKHD1-KO CCs was significantly increased by interleukin-8 (IL-8) secreted in an autocrine manner. IL-8 production was significantly elevated in PKHD1-KO CCs due to mitogen-activated protein kinase pathway activation caused by fibrocystin deficiency. The production of connective tissue growth factor (CTGF) was also increased in PKHD1-KO CCs in an IL-8-dependent manner. Furthermore, validation analysis demonstrated that both the serum IL-8 level and the expression of IL-8 and CTGF in the liver samples were significantly increased in patients with CHF, consistent with our in vitro human iPS-disease model of CHF. CONCLUSIONS: Loss of fibrocystin function promotes IL-8-dependent proliferation of, and CTGF production by, human cholangiocytes, suggesting that IL-8 and CTGF are essential for the pathogenesis of CHF. IL-8 and CTGF are candidate molecular targets for the treatment of CHF. LAY SUMMARY: Congenital hepatic fibrosis (CHF) is a genetic liver disease caused by mutations of the PKHD1 gene. Dysfunction of the protein it encodes, fibrocystin, is closely associated with CHF pathogenesis. Using an in vitro human induced pluripotent stem cell model and patient samples, we showed that the loss of fibrocystin function promotes proliferation of cholangiocytes and the production of connective tissue growth factor (CTGF) in an interleukin 8 (IL-8)-dependent manner. These results suggest that IL-8 and CTGF are essential for the pathogenesis of CHF.

LIM homeobox 2 promotes interaction between human iPS-derived hepatic progenitors and iPS-derived hepatic stellate-like cells.

Human induced pluripotent stem (iPS) cells can differentiate into hepatocyte lineages, although the phenotype of the differentiated cells is immature compared to adult hepatocytes. Improvement of cell-cell interactions between epithelium and mesenchyme is a potential approach to address this phenotype issue. In this study, we developed a model system for improving interactions between human iPS-derived hepatic progenitor cells (iPS-HPCs) and human iPS-derived hepatic stellate cell-like cells (iPS-HSCs). The phenotype of iPS-HSCs, including gene and protein expression profiles and vitamin A storage, resembled that of hepatic stellate cells. Direct co-culture of iPS-HSCs with iPS-HPCs significantly improved hepatocytic maturation in iPS-HPCs, such as their capacity for albumin production. Next, we generated iPS cell lines overexpressing LIM homeobox 2 (LHX2), which suppresses myofibroblastic changes in HSCs in mice. Hepatocytic maturation in iPS-HPCs was significantly increased in direct co-culture with iPS-HSCs overexpressing LHX2, but not in co-culture with a human hepatic stellate cell line (LX-2) overexpressing LHX2. LHX2 regulated the expression of extracellular matrices, such as laminin and collagen, in iPS-HSCs. In conclusion, this study provides an evidence that LHX2 upregulation in iPS-HSCs promotes hepatocytic maturation of iPS-HPCs, and indicates that genetically modified iPS-HSCs will be of value for research into cell-cell interactions.