Association between HBV Pre-S mutations and the intracellular HBV DNAs in HBsAg-positive hepatocellular carcinoma in China.

This study aimed to investigate the association between HBV mutations and intrahepatic HBV status and to determine the clinical features and the contribution of HBV mutations to postoperative prognosis for hepatocellular carcinoma (HCC) patients with HBsAg (+) in China. Using TaqMan fluorescent real-time PCR, HBV covalently closed circular DNA (cccDNA) and total DNA (tDNA) were both quantified in 106 pairs of tumor tissues (TT) and adjacent non-tumor tissues (ANTT) obtained from HCC patients who received no antiviral treatment before surgical treatment. The prevalence of 19 hot spot mutations was evaluated by Sanger sequencing. HBV cccDNA and tDNA were lower in TT than in ANTT. The loads of cccDNA and tDNA in ANTT were associated with serum HBV DNA and HBeAg. Three Pre-S mutants (A2962G and C2964A in Pre-S1 and C105T in Pre-S2) were associated with higher tumor cccDNA levels (P < 0.05), and A2962G/C2964A mutants were associated with higher AFP levels. This would assist to disclose the virological features, to implement a more clinically personalized therapy and to improve the prognosis of HBV-related HCC patients.

Monitoring fibrogenic progression in the liver.

The clinical course of chronic liver diseases is significantly dependent on the progression rate of fibrosis which is the unstructured replacement of injured parenchyma by extracellular matrix. Despite intensive studies, the clinical opportunities for patients with fibrosing liver diseases have not improved. This will be changed by increasing knowledge of new pathogenetic mechanisms, which complement the "canonical principle" of fibrogenesis. The latter is based on the activation of hepatic stellate cells and their transdifferentiation to myofibroblasts induced by hepatocellular injury and consecutive inflammatory mediators such as TGF-ß. Stellate cells express a broad spectrum of matrix components. New mechanisms indicate that the heterogeneous pool of (myo-)fibroblasts can be supplemented by epithelial-mesenchymal transition (EMT) from cholangiocytes and potentially also from hepatocytes to fibroblasts, by influx of bone marrow-derived fibrocytes in the damaged liver tissue and by differentiation of a subgroup of monocytes to fibroblasts after homing in the damaged tissue. These processes are regulated by the cytokines TGF-ß and BMP-7, chemokines, colony-stimulating factors, metalloproteinases and numerous trapping proteins. They offer innovative diagnostic and therapeutic options. As an example, modulation of TGF-ß/BMP-7 ratio changes the rate of EMT, and so the simultaneous determination of these parameters and of the connective tissue growth factor (CTGF) in serum might provide information on fibrogenic activity. Also, proteomic and glycomic approaches of serum are under investigation to set up specific protein profiles in patients with liver fibrosis. The aim of this article is to present the current pathogenetic concepts of liver fibrosis and to discuss established and novel diagnostic approaches to reflect the process of hepatic fibrogenesis in the medical laboratory.

Connective tissue growth factor (CTGF/CCN2) in serum is an indicator of fibrogenic progression and malignant transformation in patients with chronic hepatitis B infection.

Still a challenging medical problem is the non-invasive monitoring of patients with a variety of chronic liver diseases being on risk to develop fibrosis, cirrhosis, and, finally, primary liver cell carcinoma. Previously, we have shown that CTGF/CCN2, a down-stream mediator of TGF-ß, in serum might be a promising non-invasive biomarker of fibrosis, which is extended in the following study to cirrhosis and liver cell carcinoma. Healthy individuals (n=56), as well as fibrotic (n=77), cirrhotic (n=17), and HCC-patients (n=72) with chronic hepatitis B (HBV) infection, clinically, biochemically and histopathologically well characterized and classified, were included for the measurements of CTGF-concentrations in serum using a newly developed CTGF-enzyme immunoassay. A statistical significant increase of the mean serum CTGF-concentrations was associated with different stages of fibrosis, ranging from 15.9 µg/L (S0), 20.3 µg/L (S1/2) to 36.9 µg/L (S3/4). The highest CTGF-concentrations were measured in cirrhotic patients (43.6 µg/L), compared to healthy subjects (17.7 µg/L), followed by a decrease in cirrhotic HCC-patients (38.5 µg/L; p=0.001). Of note, HCC patients without underlying cirrhosis (n=8) had CTGF levels (13.5±13.2 µg/L) comparable to those in healthy controls. No statistical relation between CTGF levels and parameters of liver injury (e.g. AST, ALT) was noticed, but CTGF levels are correlated negatively with serum albumin levels (p=0.007) and platelet counts (p=0.0032), respectively. The latter was negatively correlated with the stage of fibrosis (p=0.025). In HCC patients, CTGF concentrations decreased with tumor progression and size, with lower levels in TNM stage II (30.5 µg/L) and stage III (33.6 µg/L) compared to TNM stage I (41.6 µg/L). Our data suggest a valuable diagnostic impact of CTGF in serum for the follow-up of patients suffering from chronic liver diseases developing fibrosis, cirrhosis and finally HCC. CTGF serum levels in HCC are most likely due to underlying fibrosis/cirrhosis but not due to malignancy per se.

Oral application of 1,7-dimethylxanthine (paraxanthine) attenuates the formation of experimental cholestatic liver fibrosis.

AIM: Several epidemiological studies suggest a beneficial effect of coffee consumption on the formation and progression of fibrogenic diseases, particularly of the liver. Recent data now point to a modulation of transforming growth factor-ß (TGF-ß) signaling by paraxanthine (1,7-dimethylxanthine [1,7-DMX]), the demethylated primary metabolite of caffeine METHODS: Twenty adult Sprague-Dawley rats were bile duct ligated (BDL) or sham operated with or without concomitant oral 1,7-DMX (1 mM) application. Serum was investigated by standard biochemical analysis, in-house connective tissue growth factor (CTGF), enzyme linked immunosorbent assay (ELISA) or liquid chromatography-mass spectrometry analysis. Liver tissue was stained using hematoxylin-eosin (HE) and Sirius-red staining. Whole liver lysates, primary rat hepatocytes (PC) and hepatic stellate cells (HSC) were investigated by CTGF, and total Smad2/3 Western blot analysis, CTGF reporter gene assay or an in-house malondialdehyde ELISA. RESULTS: The in vitro 50% inhibitory dose (ID50) of 1,7-DMX was 0.95 mM by for CTGF promoter activity and protein expression in PC and 1.25 mM for protein expression in HSC. Oral 1,7-DMX application (1 mM) attenuated cholestatic hepatocellular injury in vivo as determined by biochemical serum analysis and reduced intercellular collagen deposition in the cholestatic rat liver (HE- and Sirius-red staining). Western Blot analysis of whole liver lysates revealed a reduction of intrahepatic concentrations of Smad2/3 and CTGF following oral 1,7-DMX intake. However, serum CTGF concentrations were not reduced in 1,7-DMX treated BDL rats. Oral 1,7-DMX furthermore led to a reduction of intrahepatic lipid peroxidation (malondialdehyde concentrations) as markers of oxidative stress in BDL rats. CONCLUSION: Our pilot study warrants further studies of 1,7-DMX as a potential new drug to fight fibrotic processes, not just of the liver.

Intracrine signaling mechanisms of activin A and TGF-ß.

While autocrine stimulation of cells by Activin A and/or its family member transforming growth factor ß (TGF-ß) is a phenomenon observed in a variety of cell types, little is known of putative intracellular signaling loops of these cytokines. Intracellular actions of several peptide hormones, growth factors, as well as of extracellular signaling enzymes and DNA-binding proteins, either within target cells or within their cells of synthesis have been shown. Although these intracrine moieties are structurally diverse, they share certain characteristics of synthesis and function. Depending on the cell type, there are reports of stimulatory as well as inhibitory mechanisms induced by such intracrine mechanisms, and this also accounts for transforming growth factor ß (TGF-ß), whereas only stimulatory intracrine signaling of Activin A could be demonstrated so far. Stimulatory intracrine signaling loops of TGF-ß were shown following calpain-dependent intracellular proteolytic activation of the latent cytokine in hepatocytes under cellular stress conditions of this cytokine, leading to transcriptional activation of connective tissue growth factor (CTGF/CCN2) as a representative TGF-ß-sensitive reporter gene. In contrast to TGF-ß, increasing intrahepatocellular concentrations of Activin A are not the result of release from an intracellularly deposited latent complex, but of active de novo synthesis. The stimulatory intracrine signaling pathways of both, TGF-ß and Activin A, are proposed to occur via Alk4/Alk5 receptors and Smad2, whereas additional activation of Smad3 only seems to be involved in intracrine Activin A signaling. However, intracrine TGF-ß signaling may itself also be inhibitory as active TGF-ß is also able to bind to intracellular TGF-ß type II receptor, resulting in a ligand-induced impediment in receptor trafficking to the cell surface. Whether stimulatory or inhibitory modulation of the TGF-ß pathway takes place seems to depend on the cell type and environmental conditions. Future studies are necessary at this point.

Connective tissue growth factor reacts as an IL-6/STAT3-regulated hepatic negative acute phase protein.

AIM: To investigate the mechanisms involved in a possible modulator role of interleukin (IL)-6 signalling on CYR61-CTGF-NOV (CCN) 2/connective tissue growth factor (CTGF) expression in hepatocytes (PC) and to look for a relation between serum concentrations of these two parameters in patients with acute inflammation. METHODS: Expression of CCN2/CTGF, p-STAT3, p-Smad3/1 and p-Smad2 was examined in primary freshly isolated rat or cryo-preserved human PC exposed to various stimuli by Western blotting, electrophoretic mobility shift assay (EMSA), reporter-gene-assays and reverse-transcriptase polymerase chain reaction. RESULTS: IL-6 strongly down-regulated CCN2/CTGF protein and mRNA expression in PC, enhanceable by extracellular presence of the soluble IL-6 receptor gp80, and supported by an inverse relation between IL-6 and CCN2/CTGF concentrations in patients' sera. The inhibition of TGFß1 driven CCN2/CTGF expression by IL-6 did not involve a modulation of Smad2 (and Smad1/3) signalling. However, the STAT3 SH2 domain binding peptide, a selective inhibitor of STAT3 DNA binding activity, counteracted the inhibitory effect of IL-6 on CCN2/CTGF expression much more pronounced than pyrrolidine-dithiocarbamate, an inhibitor primarily of STAT3 phosphorylation. An EMSA confirmed STAT3 binding to the proposed proximal STAT binding site in the CCN2/CTGF promoter. CONCLUSION: CCN2/CTGF is identified as a hepatocellular negative acute phase protein which is down-regulated by IL-6 via the STAT3 pathway through interaction on the DNA binding level.

Lower copy numbers of the chemokine CCL3L1 gene in patients with chronic hepatitis C.

BACKGROUND & AIMS: Recently, variation of gene copy numbers was recognized as a novel type of common genetic diversity, but its impact on viral hepatitis is unknown. Here, we determine the influence of copy number variation on the susceptibility and disease severity in hepatitis C virus (HCV) infection, investigating copy number variants (CNVs) of the chemokine CCL3L1 gene, which encodes a potent CCR5 ligand. METHODS: CNVs were determined in 254 patients with chronic hepatitis C, 144 HCV/HIV co-infected patients, and 210 HCV negative controls, using quality-controlled real-time fluorescent dye-labeled quantitative PCR. Liver biopsies were obtained from HCV infected patients. RESULTS: Copy numbers of the CCL3L1 gene range from 0 to 12 (mean 2.7+/-1.4 copies). Patients with two or less copies are over-represented in the HCV infected cohort compared to HCV negative controls (odds ratio [OR] 1.54; p=0.02). CCL3L1 copies are shifted to lower numbers in HCV infected patients (means 2.6 vs. 2.9 in controls; p=0.011). HCV/HIV co-infected patients carry even lower CCL3L1 copy numbers compared to controls (means 2.2 vs. 2.9; p<0.001), with a higher proportion of patients possessing two or less copies (OR=3.42; p<0.001). No association was detected between CCL3L1 copy numbers and histological grades of inflammation or stages of fibrosis. CONCLUSIONS: Lower CCL3L1 gene copy number compared to the population median is associated with chronic hepatitis C. Copy number variation of host genes represents a novel class of genetic diversity associated with viral hepatitis.

Impact of quality control accepted inter-laboratory variations on calculated Fibrotest/Actitest scores for the non-invasive biochemical assessment of liver fibrosis.

INTRODUCTION: Non-invasive, i.e. serum-based assessment of liver fibrosis is still an important diagnostic challenge although multiple single and multiparametric panels of biomarkers have been suggested. AIM: Two approaches were followed to determine the diagnostic reliability of Fibrotest and Actitest, two commercially distributed non-invasive multiparametric tests for staging and grading of liver fibrosis. METHODS: (i) Haptoglobin, ALT, gamma GT, alpha-2-macroglobulin, apolipoprotein A1 and bilirubin, required for calculation of respective scores, were determined in sera of 4 patients with histologically defined stages of fibrosis (F1-F4) and activities of fibrogenesis (A1-A3). Analytes were determined by 6 quality controlled external laboratories. Inter-laboratory variations of the calculated Fibrotest score for staging and Actitest score for grading (BioPredictive), and their error ratios referred to histologic results were calculated. (ii) The variability of respective Fibrotest/Actitest scores depending on 64 selected combinations of analytes within the accepted ranges of analyte-specific maximum/minimum limits given by the external quality control of the German Association of Clinical Chemistry and Laboratory Medicine (DGKL) was calculated. RESULTS: (i) Fibrotest and Actitest scores were largely reproducible among the different laboratories. However, the error ratio was 77% for all results calculated by both, Fibrotest and Actitest when referred to histologic findings. (ii) Calculated scores of stages varied between F2 (9%), F3 (31%), F3-F4 (6%), and F4 (54%) (Fibrotest), and A1/A2 (48%), A2 (9%), A2-A3 (5%), and A3 (38%) for grades of fibrogenic activity. CONCLUSION: Despite reproducibility of Fibro- and Actitest scores among the six laboratories, large scale investigation displayed high levels of variability depending on inter-laboratory differences that were still in a quality controlled, analytically acceptable range. Calculated scores coincided with histologic findings in less than 25% of all cases. Thus, the diagnostic accuracy of these tests must be considered as low, if histology is accepted as reference standard.

Increased serum xylosyltransferase activity in patients with liver fibrosis.

BACKGROUND: We investigated the xylosyltransferase (XT) activity in the serum of liver fibrotic patients with hepatitis C virus induced liver fibrosis at different stages as determined according to the scoring system of Desmet and Scheuer. METHODS: Measurement of XT activity was performed by liquid chromatography-tandem mass spectrometry. RESULTS: We found that serum XT activity in males (n=59, median+/-SD, 27.2+/-2.8 mU/L, p<0.001) and females (n=54, 23.6+/-3.0 mU/L, p<0.01) with liver fibrosis is significantly elevated in comparison to a corresponding healthy control cohort of males (n=50, 23.9+/-2.8 mU/L) and females (n=52, 21.5+/-3.7 mU/L), respectively. Of note, independent from gender, serum XT activity positively correlated with the stage of fibrosis but declined again in patients with histologically proven cirrhosis. CONCLUSIONS: XT activity is increased in the serum of patients with liver fibrosis at different stages, pointing to a possible pathogenetic role in elevated proteoglycan biosynthesis in fibrotic remodeling of this organ during chronic injury.

Less Smad2 is good for you! A scientific update on coffee's liver benefits.

Scientists at the National Institutes of Health have reported that increased coffee consumption is associated with a slower progression of fibrogenesis in patients with chronic and particularly alcoholic liver disease and a reduced incidence of heptocellular carcinoma. However, a causal mechanistic explanation was pending. New results indicate that the methylxanthine caffeine--a major component of coffee and the most widely consumed pharmacologically active substance in the world--might be responsible for this phenomenon, because it inhibits the synthesis of connective tissue growth factor (CTGF/CCN2) in liver parenchymal and nonparenchymal cells, primarily by inducing degradation of Smad2 (and to a much lesser extent Smad3) and thus impairment of transforming growth factor beta (TGF-beta) signaling. CTGF and TGF-beta play crucial roles in the fibrotic remodeling of various organs, and, ultimately, carcinogenesis. This article summarizes the clinical-epidemiological observations as well as the pathophysiological background and provides suggestions for the therapeutic use of (methyl)xanthine derivatives in the management of fibro-/carcinogenic (liver) diseases.

BMP-7 as antagonist of organ fibrosis.

Fibrosis is a scarring process that is a common feature of chronic organ injury. It is characterized by elevated activity of transforming growth factor-beta resulting in increased and altered deposition of extracellular matrix and other fibrosis-associated proteins. Recent work has demonstrated that bone morphogenetic protein-7 blocks transforming growth factor-beta signaling. Moreover, member of the CCN family, Endoglin, Sclerostin, Sclerostin domain-containing proteins, Gremlin, Noggin, Chordin, and Kielin/Chordin-like protein influence the biological activity of both cytokines. As a consequence, they modulate cellular proliferation, migration, adhesion and extracellular matrix production. This tight protein network consisting of transforming growth factor-betas, bone morphogenetic proteins and various binding partners includes potential novel molecular targets and biomarkers useful for prognostication, disease monitoring and therapy. We here summarize recent advances in understanding bone morphogenetic protein-7 function and signaling and the current attempts to use this critical modulator as a pharmacological device to reverse transforming growth factor-beta-induced fibrogenesis.

Serum resistin levels in critically ill patients are associated with inflammation, organ dysfunction and metabolism and may predict survival of non-septic patients.

INTRODUCTION: Blood glucose levels and insulin resistance in critically ill patients on admission to intensive care units (ICUs) have been identified as factors influencing mortality. The pathogenesis of insulin resistance (IR) in critically ill patients is complex and not fully understood. Resistin is a hormone mainly derived from macrophages in humans and from adipose tissue in rodents, which regulates glucose metabolism and insulin sensitivity. In non-critically ill patients, resistin was found to be related to impaired glucose tolerance, insulin resistance, metabolic syndrome, obesity and type 2 diabetes. Therefore, resistin might represent a link between inflammation, acute phase response and insulin resistance in critically ill patients. We aimed to examine the correlation of serum resistin concentrations to parameters of inflammation, organ function, metabolism, disease severity and survival in critically ill patients. METHODS: On admission to the Medical ICU, 170 patients (122 with sepsis, 48 without sepsis) were studied prospectively and compared with 60 healthy non-diabetic controls. Clinical data, various laboratory parameters, metabolic and endocrine functions as well as investigational inflammatory cytokine profiles were assessed. Patients were followed for approximately three years. RESULTS: Resistin serum concentrations were significantly elevated in all critical care patients compared with healthy controls, and significantly higher in sepsis than in non-sepsis patients. Serum resistin concentrations were not associated with pre-existing type 2 diabetes or obesity. For all critically ill patients, a correlation to the homeostasis model assessment index of insulin resistance (HOMA-IR) was shown. Serum resistin concentrations were closely correlated to inflammatory parameters such as C-reactive protein, leukocytes, procalcitonin, and cytokines such as IL6 and TNF-alpha, as well as associated with renal failure and liver synthesis capacity. High resistin levels (> 10 ng/ml) were associated with an unfavourable outcome in non-sepsis patients on ICU and the overall survival. CONCLUSIONS: Serum resistin concentrations are elevated in acute inflammation due to sepsis or systemic inflammatory response syndrome (SIRS). The close correlation with other acute phase proteins suggests a predominant, clinically relevant resistin release from macrophages in ICU patients. Moreover, resistin could potentially serve as a prognostic biomarker in non-sepsis critically ill patients.

Non-invasive biomarkers for monitoring the fibrogenic process in liver: a short survey.

The clinical course of chronic liver diseases is significantly dependent on the progression rate and the extent of fibrosis, i.e. the non-structured replacement of necrotic parenchyma by extracellular matrix. Fibrogenesis, i.e. the development of fibrosis can be regarded as an unlimited wound healing process, which is based on matrix (connective tissue) synthesis in activated hepatic stellate cells, fibroblasts (fibrocytes), hepatocytes and biliary epithelial cells, which are converted to matrix-producing (myo-)fibroblasts by a process defined as epithelial-mesenchymal transition. Blood (non-invasive) biomarkers of fibrogenesis and fibrosis can be divided into class I and class II analytes. Class I biomarkers are those single tests, which are based on the pathophysiology of fibrosis, whereas class II biomarkers are mostly multiparametric algorithms, which have been statistically evaluated with regard to the detection and activity of ongoing fibrosis. Currently available markers fulfil the criteria of ideal clinical-chemical tests only partially, but increased understanding of the complex pathogenesis of fibrosis offers additional ways for pathophysiologically well based serum (plasma) biomarkers. They include TGF-beta-driven marker proteins, bone marrow-derived cells (fibrocytes), and cytokines, which govern pro- and anti-fibrotic activities. Proteomic and glycomic approaches of serum are under investigation to set up specific protein or carbohydrate profiles in patients with liver fibrosis. These and other novel parameters will supplement or eventually replace liver biopsy/histology, high resolution imaging analysis, and elastography for the detection and monitoring of patients at risk of developing liver fibrosis.

Connective tissue growth factor is a Smad2 regulated amplifier of transforming growth factor beta actions in hepatocytes--but without modulating bone morphogenetic protein 7 signaling.

UNLABELLED: In vivo knockdown of connective tissue growth factor (CTGF/CCN2) was recently shown to attenuate the formation of experimental liver fibrosis. The secreted, cysteine-rich growth factor is proposed to adversely modulate the binding of profibrogenic transforming growth factor beta (TGF-beta) and its natural antagonist bone morphogenetic protein (BMP) to their cognate receptors in several cellular systems, but the functionality of CTGF in modulation of the TGF-beta/BMP signaling pathways is still unknown. This study aims at characterizing a potentially differential modulating role of CTGF on TGF-beta- and BMP7-dependent transactivation of reporter gene [Ad-(CAGA)(12)-MLP-luc, Ad-hCTGF-luc, and Ad-(BRE)(2)-luc reporter gene] expression in rat hepatocytes. In this context, emphasis is also placed on the differential roles of Smad2 and Smad3 in the TGF-beta-dependent transactivation of the endogenous CTGF gene and the CTGF gene reporter, as investigated following adenoviral infection of wild-type and dominant negative Smad2/3 or treatment with the specific inhibitor of Smad3 or ALK5-specific (SB-431542) inhibitor. In this analysis, we found (1) a selective transcriptional activation of the CTGF promoter by Smad2 (but not Smad3); (2) the failure of BMP7 to inhibit the transcriptional activation of the Smad3-selective (CAGA)(12)-luc reporter by TGF-beta, as well as the failure of TGF-beta to inhibit the transcriptional activation of the Smad5-selective (BRE)(2)-luc reporter by BMP7; and (3) the sensitization of hepatocytes toward TGF-beta type I receptor (ALK5)/Smad2 and Smad3-mediated TGF-beta signaling by CTGF, whereas BMP type I receptor (ALK1)/Smad5-mediated BMP7 signaling is not modulated. CONCLUSION: CTGF acts as a Smad2-dependent sensitizer of TGF-beta actions that does not influence BMP7 signaling in hepatocytes.

Identification of paraxanthine as the most potent caffeine-derived inhibitor of connective tissue growth factor expression in liver parenchymal cells.

BACKGROUND: Recently, we identified hepatocytes as the major cellular source of profibrogenic connective tissue growth factor (CTGF/CCN2) in the liver. Based on reports of a hepatoprotective effect of coffee consumption, we were the first to provide evidence that caffeine suppresses transforming growth factor (TGF)-beta dependent and -independent CTGF expression in hepatocytes in vitro and in vivo, thus suggesting this xanthine-alkaloid as a potential therapeutic agent. AIM: This study aims at comparing the inhibitory capacities of caffeine and its three demethylated derivates paraxanthine, theophylline and theobromine on CTGF expression in hepatocytes and hepatic stellate cells (HSC). RESULTS: Our data suggest paraxanthine as the most important pharmacological repressor of hepatocellular CTGF expression among the caffeine-derived metabolic methylxanthines with an inhibitory dosage (ID)50 of 1.15 mM, i.e. 3.84-fold lower than what is observed for caffeine. In addition, paraxanthine displayed the least cell toxicity as proven by the water-soluble tetrazolium-1 cell vitality assay. However, caffeine or any of the metabolites did not inhibit CTGF expression in HSC. At the toxicological threshold concentration of 1 mM for paraxanthine, we observed an inhibition of hepatocellular CTGF synthesis by 44%, which was strongly reverted in the presence of the specific competitive cyclic adenosine monophosphate inhibitor Rp-adenosine 3',5-cyclic monophosphorothioate triethylammonium salt. Furthermore, CTGF protein expression induced by various concentrations of TGF-beta (0.13-1 ng/ml) is still reduced by, on average, 27%/45% in the presence of paraxanthine (1.25 mM/2.5 mM). CONCLUSION: Our data provide an evidence-based suggestion of the caffeine-derived primary metabolite paraxanthine as a potentially powerful antifibrotic drug by its inhibitory effect on (hepatocellular) CTGF synthesis.

Evaluation of serum percent trisialotransferrin as potential predictive biomarker of hepatocellular dedifferentiation in chronic liver disease.

BACKGROUND AND AIM: Chronic hepatitis induced liver fibrogenesis is characterized by epithelial-to-mesenchymal transition of liver parenchymal cells (hepatocytes) to fibroblast (-like cells), i.e. increasing hepatocellular dedifferentiation, ultimatively leading to the development of hepatocellular carcinoma (HCC). Up to now the spectrum of valid serum biomarkers for this process of hepatocellular dedifferentiation is very limited. We therefore investigated the dynamics of alterations in the serum transferrin isoform pattern in the pathogenetic sequence from liver fibrosis to hepatocellular carcinoma, to evaluate the suitability of one of the isoforms as potential biomarker for hepatocellular dedifferentiation in chronic liver disease. RESULTS: Our data on 252 patients with hepatitis C virus (HCV) induced fibrogenic liver disease and on 43 patients with HCV induced HCC demonstrate a dynamic alteration of serum % trisialotransferrin levels in the pathogenetic sequence from early stage hepatic fibrosis to fully developed hepatocellular carcinoma, whereas serum % di- and pentasialotransferrin values seem not to be affected. We show that patients with early stage fibrosis (METAVIR stage F1) and weak fibrogenic activitiy (METAVIR grade A1) display significantly lower values of serum % trisialotransferrin compared to healthy controls, and that serum % trisialotransferrin values increased steadily parallel to an increase of fibrotic stage and grade, respectively, while finally exceeding normal values in those patients with hepatocellular carcinoma. CONCLUSION: These findings propose a possible diagnostic value of serum % trisialotransferrin concentrations in the pathogenesis of hepatocellular dedifferentiation and the use of this parameter as possible predictive tumor marker in patients with chronic liver disease. Monitoring the pattern of transferrin bound sialic acid residues may thus be a helpful tool in assessing the risk of malignant degeneration in patients with chronic fibrogenic liver disease.

Questioning the role of actinfree Gc-Globulin as actin scavenger in neurodegenerative central nervous system disease: relationship to S-100B levels and blood-brain barrier function.

INTRODUCTION: Preliminary studies report on significantly higher levels of the major cytoskeleton protein actin in CSF of patients with neurodegenerative conditions and that the dynamics of these levels obviously correlates with disease progression and clinical disability. One of the primary functions of actinfree Gc-Globulin is to bind and neutralize extracellular monomeric actin, released into the circulation by necrotic or ruptured cells, and thus ameliorating the clinical outcome in situations of severe organ damage. AIM AND METHODS: This is the first study to investigate actinfree Gc-Globulin and S100-B levels (as reliable marker of neurodegeneration) in paired CSF and serum samples of patients with multietiological CNS diseases. RESULTS: 42% of all patients with CNS disease displayed serum concentrations of actinfree Gc-Globulin above the established reference range. CSF concentrations of actinfree Gc-Globulin and S100-B were positively correlated with the severity of blood-brain barrier (BBB) dysfunction. Furthermore, patients with severe BBB dysfunction presented a higher percentage of intrathecal synthesis of actinfree Gc-Globulin compared to patients with mild to moderate dysfunction and to patients with normal BBB function. Representative longitudinal data from selected patients demonstrated an inverse behaviour of actinfree Gc-Globulin and S100-B CSF concentrations, suggesting a consumption of the actin scavenger capacity of Gc-Globulin in times of increased neuronal damage. This presumption was supported by the fact that those conditions associated with a severe neuronal damage, in particular CNS trauma, and highest S100-B concentrations simultaneously displayed lowest actinfree Gc-Globulin levels, and thus residual actin binding capacity of Gc-Globulin. CONCLUSION: In summary, our data propose a function of actinfree Gc-Globulin also in the clearance of actin filaments from CSF of patients with neuronal damage. However, active recruitment of hepatic derived actinfree Gc-Globulin to the site of CNS injury is not observed. Much more, BBB leakage enables extraneuronally synthesized actinfree Gc-Globulin to extent its scavenger capacity for actin also to the subarachnoidal space. Furthermore, intrathecal synthesis of actinfree Gc-Globulin seems to be increased in patients with severe neurodegeneration.

Elevated concentrations of 15-deoxy-Delta12,14-prostaglandin J2 in chronic liver disease propose therapeutic trials with peroxisome proliferator activated receptor gamma-inducing drugs.

BACKGROUND/AIMS: Current knowledge confers a crucial role to connective tissue growth factor (CTGF/CCN2) in hepatic fibrogenesis. Hepatocytes are likely to be the major cellular source of CTGF in the liver in which CTGF is sensitively upregulated by TGF-beta. Recently, we demonstrated that the methylxanthine derivate caffeine leads to an upregulation of peroxisome proliferator activated receptor gamma (PPARgamma) expression in hepatocytes, thus sensitizing these cells to the well-known inhibitory effect of 15-deoxy-Delta(12,14)-prostaglandin J(2) (15-d-PGJ(2)) on CTGF expression. However, upregulation of the receptor alone is not sufficient per se; its physiological ligand 15-d-PGJ(2) is required to exert an inhibitory effect on transforming growth factor-beta (TGF-beta) target genes such as CTGF. METHODS: This study compared serum concentrations of 15-d-PGJ(2) in Caucasian patients with fibrotic liver diseases (n=289), Caucasian controls (n=136) and Caucasian non-liver disease (NLD) sick (n=307), as well as of Chinese patients with hepatocellular carcinoma (HCC) (n=43) and Chinese healthy controls (n=63) in order to characterize their suitability for therapeutic approaches with PPARgamma-inducing (i.e. CTGF inhibitory) drugs such as caffeine. RESULTS: The presented data showed that Caucasian patients with ongoing hepatic fibrogenesis (mean 6.2+/-5.9 microg/L) displayed strikingly higher serum concentrations of 15-d-PGJ(2) than healthy probands (mean 2.3+/-1.0) and Caucasian patients with NLD (mean 2.7+/-1.4 microg/L). Similar results were found in Chinese patients with fully developed HCC (mean 1.3+/-0.7 microg/L) compared with Chinese healthy controls (mean 0.4+/-0.2 microg/L). CONCLUSIONS: In conclusion, our data thus proposed an increased suitability of these patient groups for therapeutic approaches with drugs inducing PPARgamma expression, such as methylxanthine derivates.