Genetically Engineered Mouse Models for Liver Cancer

Liver cancer is the fourth leading cause of cancer-related death globally, accounting for approximately 800,000 deaths annually. Hepatocellular carcinoma (HCC) is the most common type of liver cancer, comprising approximately 80% of cases. Murine models of HCC, such as chemically-induced models, xenograft models, and genetically engineered mouse (GEM) models, are valuable tools to reproduce human HCC biopathology and biochemistry. These models can be used to identify potential biomarkers, evaluate potential novel therapeutic drugs in pre-clinical trials, and develop molecular target therapies. Considering molecular target therapies, a novel approach has been developed to create genetically engineered murine models for HCC, employing hydrodynamics-based transfection (HT). The HT method, coupled with the Sleeping Beauty transposon system or the CRISPR/Cas9 genome editing tool, has been used to rapidly and cost-effectively produce a variety of HCC models containing diverse oncogenes or inactivated tumor suppressor genes. The versatility of these models is expected to broaden our knowledge of the genetic mechanisms underlying human hepatocarcinogenesis, allowing the study of premalignant and malignant liver lesions and the evaluation of new therapeutic strategies. Here, we review recent advances in GEM models of HCC with an emphasis on new technologies.ope

Assessment of fibrotic burden among chronic hepatitis B virus-infected patients with normal transaminase level

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Non-Inferior Efficacy of Tenofovir Disoproxil to Tenofovir Disoproxil Fumarate in Virologically Suppressed Chronic Hepatitis B Patients

Purpose: Tenofovir disoproxil (TD), modified from tenofovir disoproxil fumarate (TDF), was developed as a salt-free formulation, removing fumarate to improve the ease of oral intake by reducing the tablet's size. We evaluated the maintenance of antiviral effects and overall safety profile of TD 245 mg after switching from TDF 300 mg in patients with chronic hepatitis B (CHB). Patients and methods: CHB patients with HBV-DNA <69 IU/mL after ≥24 weeks of TDF therapy were enrolled. The primary efficacy endpoint was the HBV-DNA suppression rate (HBV-DNA <69 IU/mL) at week 48; We evaluated the non-inferiority (10% margin) of TD to TDF in terms of efficacy. Safety was assessed based on adverse events (AEs), laboratory tests, bone mineral density, and renal function abnormalities. Results: Overall, 189 subjects were randomized in a 2:1 ratio, and 117 and 66 subjects in the TD and TDF groups, respectively, completed the study. In the per-protocol set, the HBV-DNA suppression rate at week 48 was 99.1% and 100% in the TD and TDF groups, respectively. The lower limit of the 97.5% one-sided confidence interval for the intergroup difference in HBV-DNA suppression rate was -2.8%, which was greater than the prespecified margin of non-inferiority. The changes in creatinine clearance from baseline to week 48 was significantly less in the TD group and in the TDF group; -0.8 ± 9.8 versus -2.4 ± 12.8 mL/min, respectively (P=0.017). Conclusion: TD was non-inferior to TDF for maintaining viral suppression in CHB patients, showing the less decline of renal function.ope

Age, Sex, and Body Mass Index Should Be Considered When Assessing Spleen Length in Patients with Compensated Advanced Chronic Liver Disease

Background/aims: We investigated the factors related to spleen length and the diagnostic accuracy of a model using spleen length corrected by related factors, for the prediction of varices needing treatment (VNT). Methods: Various prediction models for VNT including spleen length were analyzed in the cohort of compensated advanced chronic liver disease (cACLD), defined as liver stiffness (LS) ≥10 kPa in a recent study. The associated factors for spleen length were identified in healthy subjects to improve the prediction of VNT. Results: Among 1,218 cACLD patients, VNT was noted in 249 patients (20.4%). On multivariate analysis, longer spleen length, lower platelet count, and higher LS value were independent predictors for VNT (all p<0.001). In multivariate analysis of 1,041 healthy subjects, age (β=-0.027), sex (β=0.762), and body mass index (β=0.097) were found to be significant factors for spleen length (all p<0.001). Using the β values, the estimated spleen length was calculated. To improve the prediction of VNT, the ratio of measured and estimated spleen length was calculated. Based on binary regression analysis results, the LS value-spleen ratio to platelet score (LSRPS) was calculated as follows: 0.027×LS value (kPa)+2.690×measured/estimated spleen ratio-0.011×platelet count (cells×109/L)-4.215. The area under the receiver operating characteristic of the LSRPS for VNT was 0.820, which was significantly higher than 0.797 of LS value-spleen diameter to platelet ratio score (LSPS) (p=0.006). Conclusions: Spleen length is influenced by age, sex, and body mass index in the Asian population. The LSRPS using the measured/estimated spleen ratio had higher diagnostic accuracy than LSPS in predicting VNT in patients with cACLD.ope

Endoscopic variceal obturation and retrograde transvenous obliteration for acute gastric cardiofundal variceal bleeding in liver cirrhosis

Background/aims: We retrospectively compared the effect of endoscopic variceal obturation (EVO) and retrograde transvenous obliteration (RTO) in acute cardiofundal variceal bleeding. Methods: Patients with acute cardiofundal variceal bleeding treated with EVO or RTO at two hospitals were included. Results: Ninety patients treated with EVO and 86 treated with RTO were analyzed. The mean model for end-stage liver disease score was significantly higher in EVO group than in RTO group (13.5 vs. 11.7, P = 0.016). The bleeding control rates were high (97.8% vs. 96.5%), and the treatment-related complication rates were low in both EVO and RTO groups (2.2% vs. 3.5%). During the median follow-up of 18.0 months, gastric variceal (GV) and esophageal variceal rebleeding occurred in 34 (19.3%) and 7 (4.0%) patients, respectively. The all-variceal rebleeding rates were comparable between EVO and RTO groups (32.4% vs. 20.8% at 2-year, P = 0.150), while the GV rebleeding rate was significantly higher in EVO group than in RTO group (32.4% vs. 12.8% at 2-year, P = 0.003). On propensity score-matched analysis (71 patients in EVO vs. 71 patients in RTO group), both all-variceal and GV rebleeding rates were significantly higher in EVO group than in RTO group (all P < 0.05). In Cox regression analysis, EVO (vs. RTO) was the only significant predictor of higher GV rebleeding risk (hazard ratio 3.132, P = 0.005). The mortality rates were similar between two groups (P = 0.597). Conclusions: Both EVO and RTO effectively controlled acute cardiofundal variceal bleeding. RTO was superior to EVO in preventing all-variceal and GV rebleeding after treatment, with similar survival outcomes.ope

Can Magnetic Resonance Elastography Fill a Niche in the Market for Noninvasive Assessment of Liver Fibrosis?

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From nonalcoholic fatty liver disease to metabolic-associated fatty liver disease: Big wave or ripple?

There is some dissatisfaction with the term "nonalcoholic fatty liver disease (NAFLD)," which overemphasizes alcohol and underemphasizes the importance of metabolic risk factors in this disease. Recently, a consensus recommended "metabolic (dysfunction)-associated fatty liver disease (MAFLD)" as a more appropriate term to describe fatty liver diseases (FLD) associated with metabolic dysfunction. During the definition change from NAFLD to MAFLD, subjects with FLD and metabolic abnormalities, together with other etiologies of liver diseases such as alcohol, virus, or medication who have been excluded from the NAFLD criteria, were added to the MAFLD criteria, while subjects with FLD but without metabolic abnormality, who have been included in the NAFLD criteria, were excluded from the MAFLD criteria. This means that there is an emphasis on the metabolic dysfunction in MAFLD which may underestimate the prognostic value of hepatic steatosis itself, whereas the MAFLD criteria might better identify subjects who are at a higher risk of hepatic or cardiovascular outcomes. However, non-metabolic risk NAFLD subjects who are excluded from the MAFLD criteria are missed from the diagnosis, and their potential risk can be the cause of future diseases. Although huge controversies remain, this review focused on summarizing recent studies that compared the clinical and prognostic characteristics between subjects with NAFLD and MAFLD.ope

Entecavir versus tenofovir in patients with chronic hepatitis B: Enemies or partners in the prevention of hepatocellular carcinoma

Over the past several decades, entecavir (ETV) and tenofovir disoproxil fumarate (TDF) have remained the first-line antiviral agents in several international guidelines. These two antiviral agents have shown similar short to intermediateterm efficacy, including virologic, biochemical, serologic, and histologic responses. However, huge controversies regarding the antiviral efficacy of ETV and TDF in preventing the development of hepatocellular carcinoma (HCC) still exist. In this review, we summarized recent studies that compared the treatment efficacy of ETV and TDF in terms of HCC development.ope

Serum Wisteria floribunda agglutinin-positive human Mac-2 binding protein level predicts recurrence of hepatitis B virus-related hepatocellular carcinoma after curative resection

BACKGROUND/AIMS: To investigate whether serum Wisteria floribunda agglutinin-positive human Mac-2-binding protein (WFA+-M2BP) can predict the recurrence of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) after curative resection. METHODS: Patients with chronic hepatitis B (CHB) who underwent curative resection for HCC between 2004 and 2015 were eligible for the study. Recurrence was sub-classified as early (<2 years) or late (≥2 years). RESULTS: A total of 170 patients with CHB were selected. During the follow-up period (median, 22.6 months), 64 (37.6%) patients developed recurrence. In multivariate analyses, WFA+-M2BP level was an independent predictor of overall (hazard ratio [HR]=1.490), early (HR=1.667), and late recurrence (HR=1.416), together with male sex, des-gamma carboxyprothrombin level, maximal tumor size, portal vein invasion, and satellite nodules (all P2.14 experienced recurrence more frequently than those with a WFA+-M2BP level ≤2.14 (P=0.011 by log-rank test), and had poorer postoperative outcomes than those with a WFA+-M2BP level ≤2.14 in terms of overall recurrence (56.0 vs. 34.5%, P=0.047) and early recurrence (52.0 vs. 20.7%, P=0.001). CONCLUSION: WFA+-M2BP level is an independent predictive factor of HBV-related HCC recurrence after curative resection. Further studies should investigate incorporation of WFA+-M2BP level into tailored postoperative surveillance strategies for patients with CHB.ope

Clinical application of liver stiffness measurement using transient elastography in chronic liver disease from longitudinal perspectives

Accurate determination of the presence and degree of fibrosis in liver is of great importance, because the prognosis and management strategies for chronic liver disease depend mainly on these factors. To date, liver biopsy (LB) remains the “gold standard” for assessing the severity of liver fibrosis; however, LB is often limited by its invasiveness, sampling error, and intra/inter-observer variability in histological interpretation. Furthermore, repeated LB examinations within a short time interval are indeed ineligible in a real clinical practice. Thus, due to the pressing need for non-invasive surrogates for liver fibrosis, transient elastography (TE), as a novel ultrasound based technology, has allowed a noninvasive measurement of liver stiffness and has gained in popularity over recent years. In the past few years, additional roles for transient TE beyond the initial purpose of a non-invasive surrogate for LB have included the prediction of the most two critical consequences of fibrosis progression: the development of portal hypertension-related complications and hepatocellular carcinoma. This indicates that the role of transient TE is not merely limited to reducing the need for LB, but transient TE can enable the establishment of tailored management strategies by providing more detailed prognostic information. In particular, under the concept in which the clinical course of liver fibrosis is dynamic and bidirectional, especially when appropriate intervention is commenced, transient TE can be used to track the dynamic changes in fibrotic burden during antiviral or antifibrotic treatment. This review discussed extended applications of transient TE in prediction of the development of real clinical endpoints from a longitudinal perspective.ope