Key features of the environment promoting liver cancer in the absence of cirrhosis.

The prevalence of obesity and non-alcoholic fatty liver disease (NAFLD) associated hepatocellular carcinoma (HCC) is rising, even in the absence of cirrhosis. We aimed to develop a murine model that would facilitate further understanding of NAFLD-HCC pathogenesis. A total of 144 C3H/He mice were fed either control or American lifestyle (ALIOS) diet, with or without interventions, for up to 48 weeks of age. Gross, liver histology, immunohistochemistry (IHC) and RNA-sequencing data were interpreted alongside human datasets. The ALIOS diet promoted obesity, elevated liver weight, impaired glucose tolerance, non-alcoholic fatty liver disease (NAFLD) and spontaneous HCC. Liver weight, fasting blood glucose, steatosis, lobular inflammation and lipogranulomas were associated with development of HCC, as were markers of hepatocyte proliferation and DNA damage. An antioxidant diminished cellular injury, fibrosis and DNA damage, but not lobular inflammation, lipogranulomas, proliferation and HCC development. An acquired CD44 phenotype in macrophages was associated with type 2 diabetes and NAFLD-HCC. In this diet induced NASH and HCC (DINAH) model, key features of obesity associated NAFLD-HCC have been reproduced, highlighting roles for hepatic steatosis and proliferation, with the acquisition of lobular inflammation and CD44 positive macrophages in the development of HCC-even in the absence of progressive injury and fibrosis.

Elastic fibres in alcoholic liver disease.

The literature on the contribution of elastic fibre deposition to alcohol-related liver disease (ARLD) is limited. We studied: (1) 180 liver biopsies from ARLD patients; (2) 20 ARLD explant livers; (3) 213 liver biopsies with non-ARLD injury. Elastic fibres were assessed in terms of their distribution around hepatocytes [pericellular elastosis (PCE)] and within bridging fibrous septa (septal elastosis) and scored using a semiquantitative system. We also investigated the composition of the elastic fibres (oxytalan, elaunin and mature elastic fibres) in 20 cases. PCE was associated with steatohepatitis in ARLD patients and with ARLD when compared to non-ARLD cases (p < 0.001). Oxytalan fibres were identified in PCE in ARLD biopsies and broken dense perisinusoidal mature elastic fibres in explanted livers. Septal elastosis increased from intermediate to advanced fibrosis stage. Early septal elastosis contained oxytalan fibres, whereas septal elastosis at more advanced stages contained mainly mature elastic fibres. PCE is a typical feature of steatohepatitis in ARLD and includes oxytalan fibres. Septal elastosis is a gradual process with a transition from oxytalan to mature elastic fibres usually present in explanted livers. There may be different dynamics in the assembly and reabsorption of pericellular and septal elastic fibres, and a potential role for stratification of patients with advanced stage ARLD.

Sinusoidal and pericellular fibrosis in adult post-transplant liver biopsies: association with hepatic stellate cell activation and patient outcome.

Post-transplant sinusoidal fibrosis (SF) and pericellular fibrosis (PCF) have not been extensively investigated in adults. Fifty-two post-transplant liver biopsies from 28 consented patients (12 men, mean age 49, range 33-67 years) were studied. Tissue morphology, including an arbitrary summative fibrosis score was assessed in detail. Collagen proportionate area (CPA) and alpha-smooth muscle actin (α-SMA) immunostain were evaluated by digital image analysis (DIA). Anti-keratin 7, anti-C4d and anti-sonic hedgehog (Shh) immunostains were scored semi-quantitatively. SF was observed in 36/52 (69.2%) biopsies and most of these (20/36, 55.6%) had centrilobular fibrosis (CLF). PCF was seen in 7/52 (13.5%) biopsies exclusively in cases with CLF. CPA was significantly correlated with time since liver transplantation (p = 0.043), summative fibrosis score and its main components but not with α-SMA. α-SMA-positive area significantly correlated with the Banff rejection score (p = 0.022) and centrilobular inflammatory changes were more severe in cases with CLF (p = 0.003). Hepatocyte ballooning of cholestatic type was associated with PCF (p = 0.016) and Shh expression (p < 0.001). Sinusoidal fibrosis is a frequent occurrence in post-transplant adult livers, with predilection toward centrilobular areas. Graft age and oxidative stress may contribute to SF development, while hepatocyte ballooning may be implicated in PCF development. Hepatic stellate cell (HSC) activation is likely affected by centrilobular inflammation.