Lay Summaries - Volume 68 Issue 5
Lay Summary: Sofosbuvir/velpatasvir taken once daily for 12?weeks resulted in high sustained virologic response rates in patients infected with HCV, irrespective of the presence of NS5A resistance-associated variants prior to treatment. Single class NS5A inhibitor resistance, but not sofosbuvir resistance, was detected in the few patients with virologic failure. These data highlight the high barrier to resistance of this regimen for the treatment of chronic HCV across all genotypes in the vast majority of patients.
Lay Summary: Hepatitis C is an infectious disease that mainly infects the liver, but has also been shown to have negative effects on other organs. This nationwide study demonstrates an increased risk of hepatitis C patients developing reduced kidney function and the need for dialysis. The study also showed improved survival in dialysis patients who received antiviral treatment.
Lay Summary: New therapies to treat chronic hepatitis B (CHB) are urgently needed. In this study we performed a retrospective analysis of liver and blood samples from a chimpanzee model of CHB to help understand how GS-9620, a drug in clinical trials, suppressed hepatitis B virus (HBV). We found that the antiviral response to GS-9620 was associated with accumulation of immune cells in the liver that can either kill cells infected with HBV or can produce antibodies that may prevent HBV from infecting new liver cells. These findings have important implications for how GS-9620 may be used in patients and may also help guide the development of new therapies to treat chronic HBV infection.
Lay Summary: GS-9620 is a drug currently being tested in clinical trials for the treatment of chronic hepatitis B virus (HBV) infection. GS-9620 has previously been shown to suppress HBV in various animal models, but the underlying antiviral mechanisms were not completely understood. In this study, we determined that GS-9620 does not directly activate antiviral pathways in human liver cells, but can induce prolonged suppression of HBV via induction of an antiviral cytokine called interferon. However, interferon did not destroy the HBV genome, suggesting that other parts of the immune response (e.g. activation of immune cells that kill infected cells) also play an important role in the antiviral response to GS-9620.
Lay Summary: In Iceland, a nationwide program has been launched offering treatment for the entire population living with hepatitis C virus (HCV). A mathematical model was used to estimate the additional health system requirements to achieve the HCV elimination targets of the World Health Organization (WHO), as well as the year that this could occur. With some additional screening of people who inject drugs, Iceland could reach the WHO targets by 2020, becoming one of the first countries to achieve HCV elimination. The model estimated that once elimination targets were reached, maintaining current monitoring and harm reduction services while providing ongoing access to DAA therapy for people diagnosed with HCV would ensure that future HCV outbreaks are unlikely to occur.
Lay Summary: The prognosis of patients with severe comorbidities may not benefit from HCV viral clearance. An algorithm to decide who will benefit from the treatment is needed to manage the chronic HCV infection better.
Lay Summary: There are two main stages in cirrhosis, compensated and decompensated, each with a main relevant outcome. In compensated cirrhosis the main relevant outcome is the development of ascites, while in decompensated cirrhosis it is death. Major roles of cardiac dysfunction and systemic inflammation have been hypothesized in the evolution of the disease in decompensated patients. In this study, we have shown that these factors were also involved in the progression from compensated to decompensated stage.
Lay Summary: We here analyzed genomic features of 412 BTC samples from Japanese and Italian populations. A total of 32 significantly and commonly mutated genes were identified, some of which negatively affected patient prognosis, including a novel deletion of MUC17 at 7q22.1. Cell-of-origin predictions using WGS and epigenetic features suggest hepatocyte-origin of hepatitis-related ICCs. Deleterious germline mutations of cancer-predisposing genes were detected in 11% of patients with BTC. BTCs have distinct genetic features including somatic events and germline predisposition.
Lay Summary: For patients with unresectable malignant biliary obstruction (MBO), placement of a self-expandable metallic stent (SEMS) is a recommended palliative modality to relieve pruritus, cholangitis, pain, and jaundice. However, restenosis is a main pitfall after stent placement. Data from this first multicenter randomized controlled trial showed that insertion of an irradiation stent provided longer patency and better survival than a conventional metal stent.
Lay Summary: Cancer recurrence can occur after liver resection or liver transplantation for hepatocellular carcinoma (HCC). This study suggests that intestinal venous congestion, which often occurs during liver surgery, favors the translocation of gut-derived bacterial products in the portal vein, thereby facilitating cancer recurrence by enhancing the signaling of Toll-like receptor 4 in the liver. Using a mouse model of HCC recurrence, we show that strategies that (i) reduce bacterial translocation (by gut decontamination, or by protecting the intestine from venous ischemia damage) or (ii) inhibit Tlr4 signaling in the liver, could reduce cancer recurrence.
Lay Summary: Acute liver injury which can cause lethal liver failure is medicated by a class of proteins called cytokines. Among these, interleukin-1 (IL-1) and the corresponding receptor IL-1R1 play a prominent role in the immune system, but their role in the liver is undetermined. In the current study, a novel mouse model with defective IL-1R1 in liver cells was studied. Mice lacking this receptor in liver cells were protected from cell death to a certain extent. This protection occurred only in the presence of other, neighboring cells, arguing for the involvement of proteins derived from these cells. This effect is called paracrine signaling and the current study has for the first time shown that the IL-1R1 receptor on hepatocytes is involved in acute liver failure in this context. The approved drug anakinra – which blocks IL-1R1 – had the same effect, supporting the proposed mechanism of action. The findings of this study suggest new treatment options for patients with acute liver failure by blocking defined signals of the immune system.
Lay Summary: HSP72 constitutes a stress-inducible, protective protein. Our data demonstrate that it is upregulated in patients with chronic hepatitis C and non-alcoholic steatohepatitis. Moreover, Hsp72-overexpressing mice are protected from various forms of liver stress.
Lay Summary: Plectin is a cytolinker protein capable of interconnecting all three cytoskeletal filament systems and linking them to plasma membrane-bound junctional complexes. In liver, the plectin-controlled cytoskeleton mechanically stabilizes epithelial cells and provides them with the capacity to adapt to increased bile pressure under cholestasis.
Lay Summary: In asymptomatic individuals, non-alcoholic fatty liver disease (NAFLD) was an independent risk factor for non-calcified plaque, which has been known as a vulnerable plaque associated with sudden and unexpected cardiac events. Therefore, appropriate medical therapy for NAFLD was required to reduce future cardiac events.
Lay Summary: CAP is a new ultrasound-based technique for measuring fat content in the liver, but has never been tested for fatty liver caused by alcohol. Herein, we examined 562 patients in a multicentre setting. We show that CAP highly correlates with liver fat, and patients with a CAP value above 290?dB/m were highly likely to have more than 5% fat in their livers, determined by liver biopsy. CAP was also better than regular ultrasound for determining the severity of alcoholic fatty-liver disease. Finally, we show that three in four (non-obese) patients rapidly decrease in CAP after short-term alcohol withdrawal. In contrast, obese alcohol-overusing patients were more likely to have higher CAP values than lean patients, irrespective of drinking.