Keratin (K)19, a biliary/hepatic progenitor cell (HPC) marker, is expressed in a subset of hepatocellular carcinomas (HCC) with poor prognosis. The underlying mechanisms driving this phenotype of ...K19-positive HCC remain elusive.
Clinicopathological value of K19 was compared with EpCAM, and α-fetoprotein, in a Caucasian cohort of 242 consecutive patients (167 surgical specimens, 75 needle biopsies) with different underlying aetiologies. Using microarrays and microRNA profiling the molecular phenotype of K19-positive HCCs was identified. Clinical primary HCC samples were submitted to in vitro invasion assays and to side population analysis. HCC cell lines were transfected with synthetic siRNAs against KRT19 and submitted to invasion and cytotoxicity assays.
In the cohort of surgical specimens, K19 expression showed the strongest correlation with increased tumour size (p<0.01), decreased tumour differentiation (p<0.001), metastasis (p<0.05) and microvascular invasion (p<0.001). The prognostic value of K19 was also confirmed in a set of 75 needle biopsies. Profiling showed that K19-positive HCCs highly express invasion-related/metastasis-related markers (eg, VASP, TACSTD2, LAMB1, LAMC2, PDGFRA), biliary/HPC markers (eg, CD133, GSTP1, NOTCH2, JAG1) and members of the miRNA family 200 (eg, miR-141, miR-200c). In vitro, primary human K19-positive tumour cells showed increased invasiveness, and reside in the chemoresistant side population. Functionally, K19/KRT19 knockdown results in reduced invasion, loss of invadopodia formation and decreased resistance to doxorubicin, 5-fluorouracil and sorafenib.
Giving the distinct invasive properties, the different molecular profile and the poor prognostic outcome, K19-positive HCCs should be considered as a seperate entity of HCCs.
Transient elastography (TE) has received increasing attention as a means to evaluate disease progression in chronic liver disease patients. In this study, we assessed the value of TE for the ...prediction of fibrosis stage in a cohort of pediatric patients with nonalcoholic steatohepatitis. Furthermore, TE interobserver agreement was evaluated. TE was performed in 52 consecutive biopsy‐proven nonalcoholic steatohepatitis patients (32 males, 20 females, age 13.6 ± 2.44 years). The area under the receiver operating characteristic curves for the prediction of “any” (≥1), significant (≥2), or advanced fibrosis (≥3) were 0.977, 0.992, and 1, respectively. Calculation of multilevel likelihood ratios showed that TE values <5, <7, and <9 kPa, suggest the presence of “any” fibrosis, significant fibrosis, and advanced fibrosis, respectively. TE values between 5 and 7 kPa predict a fibrosis stage of 1, but with some degree of uncertainty. TE values between 7 and 9 kPa predict fibrosis stages 1 or 2, but cannot discriminate between these two stages. TE values of at least 9 kPa are associated with the presence of advanced fibrosis. The intraclass correlation coefficient for absolute agreement was 0.961. Conclusion: TE is an accurate and reproducible methodology to identify pediatric subjects without fibrosis or significant fibrosis, or with advanced fibrosis. In patients in which likelihood ratios are not optimal to provide a reliable indication of the disease stage, liver biopsy should be considered when clinically indicated. (HEPATOLOGY 2008.)
Fibrogenesis represents the main pathophysiological consequence of chronic liver disease and leads to life-threatening clinical consequences. The knowledge in this field has grown exponentially in ...the past 20 years and, currently, evaluation and treatment of liver fibrosis are central issues in hepatology. Classic mechanisms of liver fibrogenesis have been expanded and consolidated over the past few years. Concomitantly, novel mechanisms have been suggested and demonstrated. The aim of this article is to provide an update on these mechanisms with an attempt to integrate classic and novel pathways responsible for the evolution of the fibrogenic process and, potentially, for its regression.
Liver tissue alterations other than fibrosis may have an impact on liver stiffness measurement. In this study we evaluated 18 patients without a previous clinical history of liver disease, ...consecutively admitted for acute viral hepatitis. In each patient, aminotransferase determination and liver stiffness measurement were performed on the same study day, at 3 different points: (1) peak increase in aminotransferase; (2) aminotransferase 50% or less of the peak; (3) aminotransferase levels ≤2× the upper limit of normal. In all patients, the degree of liver stiffness at the time of the peak increase in aminotransferases exceeded the cutoff values proposed for the prediction of significant fibrosis or cirrhosis. A progressive significant reduction in liver stiffness values was observed (P < 0.0001) in the follow‐up period in parallel with the reduction of aminotransferase levels (P < 0.0001). Moreover, a statistically significant, positive correlation between aminotransferases and liver stiffness measurement (LSM) at the onset of acute viral hepatitis was found (r = 0.53, P = 0.02 and r = 0.51, P = 0.03 for alanine aminotransferase and aspartate aminotransferase, respectively). In conclusion, the extent of necroinflammatory activity needs to be carefully considered in future studies aimed at further validating transient elastography, particularly in patients with absent or low‐stage liver fibrosis (in other words, F0‐F2 METAVIR). LSM does not represent a reliable instrument to detect the presence of advanced fibrosis and cirrhosis in patients presenting with a clinical picture of acute hepatitis. (HEPATOLOGY 2007.)
Background
Although malnutrition and sarcopenia are prevalent in cirrhosis, their impact on outcomes following liver transplantation is not well documented.
Methods
The associations of nutritional ...status and sarcopenia with post‐transplant infections, requirement for mechanical ventilation, intensive care (ICU) and hospital stay, and 1 year mortality were assessed in 232 consecutive transplant recipients. Nutritional status and sarcopenia were assessed using the Royal Free Hospital‐Global Assessment (RFH‐GA) tool and the L3‐psoas muscle index (L3‐PMI) on CT, respectively.
Results
A wide range of RFH‐SGA and L3‐PMI were observed within similar Model for End‐stage Liver Disease (MELD) sub‐categories. Malnutrition and sarcopenia were independent predictors of all outcomes. Post‐transplant infections were associated with MELD (OR = 1.055, 95%CI = 1.002–1.11) and severe malnutrition (OR = 6.55, 95%CI = 1.99–21.5); ventilation > 24 h with MELD (OR = 1.1, 95%CI = 1.036–1.168), severe malnutrition (OR = 8.5, 95%CI = 1.48–48.87) and suboptimal donor liver (OR = 2.326, 95%CI = 1.056–5.12); ICU stay > 5 days, with age (OR = 1.054, 95%CI = 1.004–1.106), MELD (OR = 1.137, 95%CI = 1.057–1.223) and severe malnutrition (OR = 7.46, 95%CI = 1.57–35.43); hospital stay > 20 days with male sex (OR = 2.107, 95%CI = 1.004–4.419) and L3‐PMI (OR = 0.996, 95%CI = 0.994–0.999); 1 year mortality with L3‐PMI (OR = 0.996, 95%CI = 0.992–0.999). Patients at the lowest L3‐PMI receiving suboptimal grafts had longer ICU/hospital stay and higher incidence of infections.
Conclusions
Malnutrition and sarcopenia are associated with early post‐liver transplant morbidity/mortality. Allocation indices do not include nutritional status and may jeopardize outcomes in nutritionally compromised individuals.
The term “liver tissue engineering” summarizes one of the ultimate goals of modern biotechnology: the possibility of reproducing in total or in part the functions of the liver in order to treat acute ...or chronic liver disorders and, ultimately, create a fully functional organ to be transplanted or used as an extracorporeal device. All the technical approaches in the area of liver tissue engineering are based on allocating adult hepatocytes or stem cell‐derived hepatocyte‐like cells within a three‐dimensional structure able to ensure their survival and to maintain their functional phenotype. The hosting structure can be a construct in which hepatocytes are embedded in alginate and/or gelatin or are seeded in a pre‐arranged scaffold made with different types of biomaterials. According to a more advanced methodology termed three‐dimensional bioprinting, hepatocytes are mixed with a bio‐ink and the mixture is printed in different forms, such as tissue‐like layers or spheroids. In the last decade, efforts to engineer a cell microenvironment recapitulating the dynamic native extracellular matrix have become increasingly successful, leading to the hope of satisfying the clinical demand for tissue (or organ) repair and replacement within a reasonable timeframe. Indeed, the preclinical work performed in recent years has shown promising results, and the advancement in the biotechnology of bioreactors, ex vivo perfusion machines, and cell expansion systems associated with a better understanding of liver development and the extracellular matrix microenvironment will facilitate and expedite the translation to technical applications. (Hepatology Communications 2018;2:131–141)
The term “liver tissue engineering” summarizes one of the ultimate goals of modern biotechnology: the possibility of reproducing in total or in part the functions of the liver in order to treat acute or chronic liver disorders and, ultimately, create a fully functional organ to be transplanted or used as extracorporeal device.
Although histopathological analysis of liver tissue is still the reference standard for the evaluation of disease progression in patients with chronic liver disease, a distinct change in clinical ...practice is occurring. The tendency to substitute histopathological analysis of liver biopsies with complex, surrogate 'noninvasive' measures of disease progression has grown to such a level that clarification and guidance on their use is needed. This Review provides an overview of the proposed noninvasive diagnostic methodologies and their possible integration with the standard invasive procedures used for the evaluation of disease progression (i.e. liver biopsy and the measurement of portal pressure). A concise analysis of what has been proposed for the differentiation of simple fatty liver from nonalcoholic steatohepatitis and its possible fibrogenic evolution is also included. In particular, the Review focuses on the methods easily available as part of daily clinical practice in hepatology--biochemical markers and transient elastography (i.e. liver stiffness measurement).
Background & Aims Hepatic venous pressure gradient (HVPG) measurement represents the best predictor of clinical decompensation (CD) in cirrhotic patients. Recently data show that measurement of ...spleen stiffness (SS) has an excellent correlation with HVPG levels. Aim of the present prospective study was to assess SS predictive value for CD compared to HVPG, liver stiffness (LS), and other non-invasive tests for portal hypertension in a cohort of patients with HCV-related compensated cirrhosis. Methods From an initial cohort of 124 patients, 92 underwent baseline LS, SS, HVPG measurements and upper gastrointestinal endoscopy at enrolment and then followed-up for 2 years or until the occurrence of the first CD. Univariate and multivariate logistic regression models were used for determining judgement criteria associated parameters. Accuracy of predictive factors was evaluated using c statistic. The final model was internally validated using the bootstrap method. Results During follow-up, 30 out 92 (32.6%) patients developed CD. At univariate analysis varices at enrolment, all non-invasive parameters, HVPG, and model for end-stage liver disease (MELD) resulted clinical predictors of CD. At multivariate analysis only SS ( p = 0.0001) and MELD ( p = 0.014) resulted as predictive factors. A decision algorithm based on the results of a predictive model was proposed to detect patients with low risk of decompensation. Conclusions This study shows that in compensated cirrhotic patients a SS and MELD predictive model represents an accurate predictor of CD with accuracy at least equivalent to that of HVPG. If confirmed by further studies, SS and MELD could represent valid alternatives to HVPG as prognostic indicator of CD in HCV-related cirrhosis.
The development of human liver scaffolds retaining their 3-dimensional structure and extra-cellular matrix (ECM) composition is essential for the advancement of liver tissue engineering. We report ...the design and validation of a new methodology for the rapid and accurate production of human acellular liver tissue cubes (ALTCs) using normal liver tissue unsuitable for transplantation. The application of high shear stress is a key methodological determinant accelerating the process of tissue decellularization while maintaining ECM protein composition, 3D-architecture and physico-chemical properties of the native tissue. ALTCs were engineered with human parenchymal and non-parenchymal liver cell lines (HepG2 and LX2 cells, respectively), human umbilical vein endothelial cells (HUVEC), as well as primary human hepatocytes and hepatic stellate cells. Both parenchymal and non-parenchymal liver cells grown in ALTCs exhibited markedly different gene expression when compared to standard 2D cell cultures. Remarkably, HUVEC cells naturally migrated in the ECM scaffold and spontaneously repopulated the lining of decellularized vessels. The metabolic function and protein synthesis of engineered liver scaffolds with human primary hepatocytes reseeded under dynamic conditions were maintained. These results provide a solid basis for the establishment of effective protocols aimed at recreating human liver tissue in vitro.
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