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Introduction The majority (80%) of hepatocellular carcinomas (HCC) develop within the context of advanced liver fibrosis and cirrhosis. Recent studies with ultrasound elastography have demonstrated that increased liver stiffness is a strong predictor of HCC. Aim To establish whether alterations in matrix stiffness regulate the phenotype and chemotherapeutic response of HCC cells. Method Experiments were conducted using a system of ligand-coated polyacrylamide gels of variable stiffness. Matrix stiffness (expressed as shear modulus) was modelled across a physiologically-relevant range (1–12 kPa), corresponding to values encountered in normal and fibrotic livers. Experiments were conducted in two HCC cells lines (Huh7/ HepG2). Results In each cell type, there was a consistent morphological response to changes in matrix stiffness. There was increased cell spreading on stiff gels in association with both stress-fibre and mature focal adhesion formation. Increasing matrix stiffness promoted cellular proliferation. The proliferative index (assessed by Ki67 staining) of Huh7 and HepG2 cells was 2.7-fold (p<0.001) and 12.2-fold (p<0.001) higher, respectively, when the cells were cultured on stiff (12 kPa) vs soft (1 kPa) supports. Cells cultured on soft supports developed a quiescent (dormant) phenotype with marked reduction in cyclinD1/ D3 expression, without upregulation of p21/p27. We postulated that altered sensitivity to mitogenic growth factors mediates the stiffness-dependent regulation of proliferation. Matrix stiffness modulated both the magnitude and time-course of mitogenic signalling in response to HGF, with lower baseline and HGF-induced FAK, ERK and STAT3 pathway activation. Increasing stiffness results in upregulation of mesenchymal markers (including N-cadherin and vimentin), consistent with mesenchymal shift, and down-regulation of differentiated hepatocyte markers (including albumin, α-1-antitrypsin and HNF4). Following treatment with cisplatin, cells cultured on soft supports were more susceptible to apoptosis (PARP/ Caspase-3 cleavage). However, in both Huh7 and HepG2 cells, surviving cells from soft supports had 2.2-fold (p<0.05) and 2.4-fold (p<0.001) higher clonogenic capacity respectively, than surviving cells from stiff supports. This was associated with upregulation of cancer stem cell markers (Oct4, NANOG, CD44, CD133, c-kit and CXCR4). Conclusion HCC is a tumour that develops within an altered biomechanical niche. Increasing matrix stiffness regulates HCC mitogenic signalling, proliferation, differentiation and chemotherapeutic resistance. However, a soft microenvironment (as may be encountered by disseminated tumour cells) promotes stem cell characteristics following chemotherapy. This provides a possible explanation for the failure of systemic chemotherapy both in relation to treatment of primary HCCs and the eradication of disseminated tumour cells that give rise to metastases. The selective targeting of the cytoskeleton represents a potentially novel approach to the treatment of HCC. [ABSTRACT FROM PUBLISHER]

Introduction Bone marrow (BM) cell populations have a number of roles in the development and resolution of chronic liver disease. Clinical trials of BM cell therapy have already begun. These have generally employed mixed cell populations often enriched for adult stem cells. Such cells may have a range of phenotypically diverse progeny. The identification of a defined cell type with beneficial effect will provide the basis of rational and predictable therapy. We have previously shown that macrophages are key mediators of scar remodelling. Iterative injury with carbon tetrachloride (CCl4) results in a well characterised model of murine hepatic fibrosis. Aim We sought to determine whether bone marrow derived macrophages (BMMs) could be used as cell therapy for liver fibrosis. Method Liver fibrosis was induced in female C57/Bl6 mice by 12 weeks i.p. carbon tetrachloride (CCl4). Macrophages were derived from the bone marrow of age-matched syngeneic mice cultured for 7 days under low adherence conditions in macrophage colony stimulating factor conditioned media. 8 weeks into the CCl4 injury protocol, mice received either 106 BMMs via the hepatic portal vein (n=8) or control medium (n=8). Serum was analysed for albumin and livers were analysed for mediators of inflammation, fibrosis and regeneration. To track donor cells, male (C57Bl/6) or transgenic green fluorescent protein+ (CBA) BMMs were delivered to strain-matched fibrotic wild type mice. Results BMMs were 88% F4/80+/CD11b+, possessed characteristic morphologic and phenotypic features, and expressed the chemokines MCP-1, MIP-1α and MIP-2. At 12 weeks, C57Bl/6 mice receiving the macrophage injection had 32% less fibrosis (mean±SEM: 2.5±0.4 vs 3.7±0.3%, p<0.05) and higher serum albumin levels (46±2.6 vs 39.9±0.86 g/l, p=0.05). Significant improvements in fibrosis and serum albumin were also demonstrated in CBA mice. Donor macrophages transiently engrafted the scar increasing hepatic levels of macrophage (MCP-1), and neutrophil (MIP-1α, MIP-2 and KC) chemoattractants (p<0.05). This enhanced recruitment of host macrophages and neutrophils to the hepatic scar areas with associated increases in MMP-13 and MMP-9 (p<0.05). A 60% reduction in myofibroblast staining (p<0.05) followed. The early influx of host leukocytes was accompanied by a 346% increase in hepatic levels of the anti-inflammatory cytokine IL-10. Donor BMMs expressed high levels of the progenitor cell mitogen TWEAK. Macrophage recipients upregulated hepatic TWEAK by 216% with a 40% increase in the number of liver progenitor cells (p<0.05). Hepatocyte proliferation was not significantly affected. Conclusion BMM therapy decreases fibrosis and increases regeneration improving clinically meaningful parameters of chronic liver disease in this model. The actions of the donor BMMs are amplified through paracrine signalling to numerically greater endogenous cell populations. Importantly, these effects are mediated by a single differentiated donor cell type, bringing clarity to the cause-effect relationship. [ABSTRACT FROM PUBLISHER]

Introduction The peptide hormone relaxin (H2-RLN) has a broad range of biological activities including antifibrotic, anti-inflammatory and haemodynamic effects in a range of target tissues. Increased intrahepatic vascular resistance in cirrhosis is due to mechanical factors related to scarring, but also a dynamic component mediated by myofibroblast (MFB) contractility. We hypothesised that H2-RLN could modulate the dynamic attribute of portal hypertension (PHT) via a direct effect on hepatic stellate cell (HSC)-MFB mediated vasoconstriction. Aim To determine whether H2-RLN could target the contractile phenotype of activated HSC-MFBs in vitro, counterbalance the contractile response in vivo in a model of sinusoidal portal hypertension, and explore the mechanisms underlying its portal hypotensive effect. Method Gene expression in culture activated human HSCs was analysed by qRT-PCR and Western blotting. Collagen gel contraction assays were used to assess HSC-MFB contractility. Nitric oxide (NO) production was measured by Griess assay. Cirrhosis and portal hypertension was induced in age matched male Sprague–Dawley rats by 8 weeks bi-weekly i.p. CCl4, before randomisation to treatment with recombinant human H2-RLN or placebo delivered by s.c. osmotic minipump for 72 hrs (n=10 per group). Portal pressure was measured by direct cannulation. Serum H2-RLN levels were quantified by immunoassay. Liver fibrosis was measured after Sirius red staining by calculation of collagen proportionate area by digital image analysis. Finally, systemic arterial and portal pressure was measured simultaneously in groups of cirrhotic and control rats randomised to acute i.v. H2-RLN or placebo. Results Treatment of culture activated HSCs with H2-RLN downregulated expression of the major cytoskeletal protein, alpha-smooth muscle actin (alpha-SMA), in a dose dependent manner. In collagen gel contraction assays, H2-RLN inhibited HSC-MFB contraction, an effect shown by RNA interference to be mediated via RXFP-1 receptor signaling and increased NO production. Rats treated with CCl4 for 8 weeks developed micronodular cirrhosis, splenomegaly and portal hypertension. Treatment with s.c. H2-RLN for 72 h achieved physiologically relevant serum concentrations and decreased portal pressure by 24% (mean 12.8±0.8 mm Hg vs 9.8±0.3 mm Hg; p=0.002), whereas placebo had no significant effect. The observed haemodynamic response was independent of fibrosis regression. Hepatic expression of alpha-SMA and other intermediate filament proteins was markedly inhibited by H2-RLN, while eNOS activity was increased. Infusion of i.v. H2-RLN in cirrhotic rats rapidly depressed portal pressure (mean 28%±6) but not systemic pressure, compared to placebo which had minimal effect on either parameter. Conclusion We demonstrate for the first time that H2-RLN will effectively downregulate MFB contractile filament expression, contractile function and has a portal hypotensive effect in vivo. Our findings support the deployment of H2-RLN in clinical studies of cirrhosis and PHT. [ABSTRACT FROM PUBLISHER]

Background: Following the introduction of an algorithm aiming to maximise life-years gained from liver transplantation in the UK (the transplant benefit score [TBS]), donor livers were redirected from younger to older patients, mortality rate equalised across the age range and short-term waiting list mortality reduced. Understanding age-related prioritisation has been challenging, especially for younger patients and clinicians allocating non-TBS-directed livers. We aimed to assess age-related prioritisation within the TBS algorithm by modelling liver transplantation prioritisation based on data from a UK transplant unit and comparing these data with other regions., Methods: In this population-based modelling study, serum parameters and age at liver transplantation assessment of patients attending the Scottish Liver Transplant Unit, Edinburgh, UK, between December, 2002, and November, 2023, were combined with representative synthetic data to model TBS survival predictions, which were compared according to age group (25-49 years vs ≥60 years), chronic liver disease severity, and disease cause. Models for end-stage liver disease (UKELD [UK], MELD [Eurotransplant region], and MELD 3.0 [USA]) were used as validated comparators of liver disease severity., Findings: Of 2093 patients with chronic liver disease, 1808 (86%) had complete datasets and liver disease parameters consistent with eligibility for the liver transplant waiting list in the UK (UKELD ≥49). Disease severity as assessed by UKELD, MELD, and MELD 3.0 did not differ by age (median UKELD scores of 56 for patients aged ≥60 years vs 56 for patients aged 25-49 years; MELD scores of 16 vs 16; and MELD 3.0 scores of 18 vs 18). TBS increased with advancing age (R=0·45, p<0·0001). TBS predicted that transplantation in patients aged 60 years or older would provide a two-fold greater net benefit at 5 years than in patients aged 25-49 years (median TBS 1317 [IQR 1116-1436] in older patients vs 706 [411-1095] in younger patients; p<0·0001). Older patients were predicted to have shorter survival without transplantation than younger patients (263 days [IQR 144-473] in older patients vs 861 days [448-1164] in younger patients; p<0·0001) but similar survival after transplantation (1599 days [1563-1628] vs 1573 days [1525-1614]; p<0·0001). Older patients could reach a TBS for which a liver offer was likely below minimum criteria for transplantation (UKELD <49), whereas many younger patients were required to have high-urgent disease (UKELD >60). US and Eurotransplant programmes did not prioritise according to age., Interpretation: The UK liver allocation algorithm prioritises older patients for transplantation by predicting that advancing age increases the benefit from liver transplantation. Restricted follow-up and biases in waiting list data might limit the accuracy of these benefit predictions. Measures beyond overall waiting list mortality are required to fully capture the benefits of liver transplantation., Funding: None., Competing Interests: Declaration of interests BMS reports receiving honoraria from Sandoz and Chiesi. All other authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background & Aims: Cystic Fibrosis related liver disease (CFLD) is the 3rd largest cause of death in Cystic Fibrosis (CF). As advances in pulmonary therapies have increased life-expectancy, CFLD has become more prevalent. Current guidelines may underdiagnose liver fibrosis, particularly in its early stages. Newer modalities for the assessment of fibrosis may provide a more accurate assessment. FibroScan is validated in assessing fibrosis for several aetiologies including alcohol and fatty liver, the CFLD cohort have an entirely different phenotype so the cut off values are not transferrable. We appraised fibrosis assessment tools to improve diagnosis of CFLD., Methods: A prospective cohort (n = 114) of patients from the Manchester Adult Cystic Fibrosis Centre, UK were identified at annual assessment. Demographic data including co-morbidity, CFTR genotyping, biochemistry and imaging were used alongside current guidelines to group into CFLD and CF without evidence of liver disease. All patients underwent liver stiffness measurement (LSM) and assessment of serum-based fibrosis biomarker panels. A new diagnostic criterion was created and validated in a second, independent cohort., Results: 12 of 114 patient classified as CFLD according to the European Cystic Fibrosis Society best practice guidelines. No specific risk factors for development of CFLD were identified. Liver enzymes were elevated in patients with CFLD. Serum biomarker panels did not improve diagnostic criteria. LSM accurately predicted CFLD. A new diagnostic criterion was proposed and validated in a separate cohort, accurately predicating CFLD in 10 of 32 patients (31 %)., Conclusion: We present a cohort of patients with CF assessed for the presence of liver fibrosis using blood biomarkers and LSM based platforms. We propose a new, simplified diagnostic criteria, capable of accurately predicting liver disease in patients with CF.Clinical trials number: NCT04277819., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Authors. Published by Elsevier Ltd.)

Background: Fontan-associated liver disease (FALD) is universal in patients with a Fontan circulation. Hepatocellular carcinoma (HCC) is one of its severe expressions, and, though rare, frequently fatal. The purpose of this study was to describe the clinical presentation, risk factors, and outcomes of HCC in patients with a Fontan circulation., Methods: A multicenter case series of Fontan patients with a diagnosis of HCC formed the basis of this study. The case series was extended by published cases and case reports. Clinical presentation, tumor characteristics, laboratory and hemodynamic findings as well as treatment types and outcomes, were described., Results: Fifty-four Fontan patients (50% female) with a diagnosis of HCC were included. Mean age at HCC diagnosis was 30 ± 9.4 years and mean duration from Fontan surgery to HCC diagnosis was 21.6 ± 7.4 years. Median HCC size at the time of diagnosis was 4 cm with a range of 1 to 22 cm. The tumor was located in the right hepatic lobe in 65% of the patients. Fifty-one percent had liver cirrhosis at the time of HCC diagnosis. Fifty percent of the patients had no symptoms related to HCC and alpha-fetoprotein was normal in 26% of the cases. Twenty-six patients (48%) died during a median follow-up duration of 10.6 (range 1-50) months., Conclusions: HCC in Fontan patients occurs at a young age with a 1-year survival rate of only 50%. Meticulous liver surveillance is crucial to detect small tumors in the early stage., (Crown Copyright © 2020. Published by Elsevier B.V. All rights reserved.)

Increasingly end-organ injury is being demonstrated late after institution of the Fontan circulation, particularly liver fibrosis and cirrhosis. The exact mechanisms for these late phenomena remain largely elusive. Hypothesizing that exercise induces precipitous systemic venous hypertension and insufficient cardiac output for the exercise demand, that is, a possible mechanism for end-organ injury, we sought to demonstrate the dynamic exercise responses in systemic venous perfusion (SVP) and concurrent end-organ perfusion. Ten stable Fontan patients and 9 control subjects underwent incremental cycle ergometry-based cardiopulmonary exercise testing. SVP was monitored in the right upper limb, and regional tissue oxygen saturation was monitored in the brain and kidney using near-infrared spectroscopy. SVP rose profoundly in concert with workload in the Fontan group, described by the regression equation 15.97 + 0.073 watts per mm Hg. In contrast, SVP did not change in healthy controls. Regional renal (p <0.01) and cerebral tissue saturations (p <0.001) were significantly lower and decrease more rapidly in Fontan patients. We conclude that in a stable group of adult patients with Fontan circulation, high-intensity exercise was associated with systemic venous hypertension and reduced systemic oxygen delivery. This physiological substrate has the potential to contribute to end-organ injury., (Copyright © 2016 Elsevier Inc. All rights reserved.)

We identified two homozygous missense mutations in the human type II 3beta-hydroxysteroid dehydrogenase (3/betaHSD) gene, the first in codon 6 of exon II [CTT (Leu) to TTT (Phe)] in a male infant with hyperpigmented scrotum and hypospadias, raised as a male and no apparent salt-wasting since neonatal age, and the second in codon 259 of exon IV [ACG (Thr) to ATG (Met)] in a male pseudohermaphrodite with labial scrotal folds, microphallus, chordee, and fourth degree hypospadias, raised as a female and with salt-wasting disorder since neonatal age. In vitro transient expression of mutant type II 3betaHSD complementary DNAs of L6F, T259M, as well as T259R for comparison was examined by a site-directed mutagenesis and transfection of construct into COS-1 and COS-7 cells. Northern blot analysis revealed expression of similar amounts of type II 3betaHSD messenger ribonucleic acid from the COS-1 cells transfected by L6F, T259M, T259R, and wild-type (WT) complementary DNAs. Western immunoblot analysis revealed a similar amount of L6F mutant protein compared to WT enzyme from COS-1 cells, but neither L6F from COS-7 cells nor T259M or T259R mutant protein in COS-1 or COS-7 cells was detectable. Enzyme activity in intact COS-1 cells using 1 micromol/L pregnenolone as substrate in the medium after 6 h revealed relative conversion rates of pregnenolone to progesterone of 46% by WT enzyme, 22% by L6F enzyme, and 8% by T259M enzyme and less than 4% activity by T259R enzyme. Using 1 micromol/L dehydroepiandrosterone as substrate, the relative conversion rate of dehydroepiandrosterone to androstenedione after 6 was 89% by WT enzyme, 35% by L6F enzyme, 5.1% by T259M enzyme and no activity by T259R enzyme. However, the L6F mutant 3betaHSD activity, despite its demonstration in the intact cells, was not detected in homogenates of COS-1 cells or in immunoblots of COS-7 cells, suggestive of the relatively unstable nature of this protein in vitro, possibly attributable to the decreased 3betaHSD activity. In the case of T259M and T259R mutations, consistently undetectable proteins in both COS cells despite detectable messenger ribonucleic acids indicate severely labile proteins resulting in either no or very little enzyme activity, and these data further substantiate the deleterious effect of a structural change in this predicted putative steroid-binding domain of the gene. In conclusion, the findings of the in vitro study of mutant type II 3betaHSD enzyme activities correlated with a less severe clinical phenotype of nonsalt-wasting and a lesser degree of genital ambiguity in the patient with homozygous L6F mutation compared to a more severe clinical phenotype of salt-wasting and severe degree of genital ambiguity in the patient with homozygous T259M mutation in the gene.