Highlights d RSPO-LGR4 is essential for stem cell self-renewal in a subset of AML d LGR4 promotes aberrant self-renewal through cooperation with HOXA9 d RSPO3 acts as a stem cell growth factor to sustain proliferation of AML patient blasts d Clinical-grade anti-RSPO3 impairs LSC self-renewal in patient-derived xenografts

OPN is a key mediator of the alcohol-induced effects on hepatic stellate cell functions and liver fibrogenesis.

Liver disease is the greatest cause of death related to alcohol and a major public health problem. While excessive alcohol intake results in hepatosteatosis in most individuals, this can progress in some to more severe forms of liver disease including fibrosis and cirrhosis. An ongoing challenge in the management of alcoholic liver disease is the identification of liver injury early in the disease process such that intervention strategies can prevent serious long term outcomes. Given that excessive alcohol consumption results in dysregulation of lipid metabolism we applied lipid profiling technology to characterise and compare serum lipid profiles from excessive chronic drinkers with no liver disease to those with advanced alcoholic cirrhosis. In a cohort of 59 excessive drinkers (31 with liver cirrhosis and 28 with no evidence of liver disease) we used electrospray ionisation tandem mass spectrometry to measure over 300 individual lipid species in serum, including species of the major phospholipid, sphingolipid, glycerolipid and sterol classes. Six of the 25 lipid classes and subclasses were significantly associated with alcoholic liver cirrhosis; these included dihexosylceramide, trihexosylceramide, alkylphosphatidylcholine, lysoalkylphosphatidylcholine, phosphatidylinositol and free cholesterol. Multivariate classification models created with only clinical characteristics gave an optimal model with an AUC of 0.847 and an accuracy of 79.7%. The addition of lipid measurements to the clinical characteristics resulted in models of improved performance with an AUC of 0.892 and accuracy of 81.8%. The gain in AUC and accuracy of the combined models highlight the potential of serum lipids as markers of liver injury in alcoholic liver disease.

Background:Alcoholic liver disease (ALD) and non-alcoholic fatty liver disease (NAFLD) are highly prevalent liver diseases that may coexist and contribute significantly to liver disease-related mortality. Obesity is a common underlying risk factor for both disorders. There has been little research investigating the combined effects of high fat diet (HFD) and alcohol. Current mouse models of alcohol- or fat-rich diet alone do not lead to severe liver injury. There is a need to develop animal models recapitulating human settings of drinking and diet to study the mechanisms of liver injury progression.Methods:C57BL6 male mice were fed either chow or HFD ad libitum for 12 weeks. A sub-set of mice from each group were also given alcohol (2 g kg−1 body weight) twice a week via intra-gastric lavage. Animals were monitored progressively for weight gain and blood and livers were harvested at termination. The extent of liver injury was examined by histopathology as well as by liver and serum biochemistry. The expression of lipid metabolism, inflammation and fibrogenesis-related molecules was examined by quantitative reverse transcription PCR (Q-PCR) and immunofluorescence staining.Results:HFD significantly increased total body weight, triglyceride and cholesterol, whereas alcohol increased liver weight. Alcohol+HFD in combination produced maximum hepatic steatosis, increased micro- and macro-vesicular lipid droplets, increased de novo lipogenesis (steroid response-element binding protein 1 (SREBP-1) and stearoyl-CoA desaturase-1 (SCD-1)) and proliferation peroxisome activated receptor alpha (PPARα), and decreased fatty acid β-oxidation (Acyl-CoA oxidase 1 (ACOX1)). Alcohol+HFD treatment also increased the inflammation (CD45+, CD68+, F4/80+ cells; tumour necrosis factor-alpha (TNF-α), F4/80 mRNAs) and fibrogenesis (vimentin+ activated stellate cells, collagen 1 (Col1) production, transforming growth factor-beta (TGF-β) and Col-1 mRNAs) in mice livers.Conclusions:We report a novel mouse model with more severe liver injury than either alcohol or HFD alone recapitulating the human setting of intermittent alcohol drinking and HFD.