Concerted epithelial and stromal changes during progression of Barrett's Esophagus to invasive adenocarcinoma exposed by multi-scale, multi-omics analysis.

Esophageal adenocarcinoma arises from Barrett's esophagus, a precancerous metaplastic replacement of squamous by columnar epithelium in response to chronic inflammation. Multi-omics profiling, integrating single-cell transcriptomics, extracellular matrix proteomics, tissue-mechanics and spatial proteomics of 64 samples from 12 patients' paths of progression from squamous epithelium through metaplasia, dysplasia to adenocarcinoma, revealed shared and patient-specific progression characteristics. The classic metaplastic replacement of epithelial cells was paralleled by metaplastic changes in stromal cells, ECM and tissue stiffness. Strikingly, this change in tissue state at metaplasia was already accompanied by appearance of fibroblasts with characteristics of carcinoma-associated fibroblasts and of an NK cell-associated immunosuppressive microenvironment. Thus, Barrett's esophagus progresses as a coordinated multi-component system, supporting treatment paradigms that go beyond targeting cancerous cells to incorporating stromal reprogramming.

Apposition of Fibroblasts With Metaplastic Gastric Cells Promotes Dysplastic Transition.

BACKGROUND & AIMS: Elements of field cancerization, including atrophic gastritis, metaplasia, and dysplasia, promote gastric cancer development in association with chronic inflammation. However, it remains unclear how stroma changes during carcinogenesis and how the stroma contributes to progression of gastric preneoplasia. Here we investigated heterogeneity of fibroblasts, one of the most important elements in the stroma, and their roles in neoplastic transformation of metaplasia. METHODS: We used single-cell transcriptomics to evaluate the cellular heterogeneity of mucosal cells from patients with gastric cancer. Tissue sections from the same cohort and tissue microarrays were used to identify the geographical distribution of distinct fibroblast subsets. We further evaluated the role of fibroblasts from pathologic mucosa in dysplastic progression of metaplastic cells using patient-derived metaplastic gastroids and fibroblasts. RESULTS: We identified 4 subsets of fibroblasts within stromal cells defined by the differential expression of PDGFRA, FBLN2, ACTA2, or PDGFRB. Each subset was distributed distinctively throughout stomach tissues with different proportions at each pathologic stage. The PDGFRα+ subset expanded in metaplasia and cancer compared with normal, maintaining a close proximity with the epithelial compartment. Co-culture of metaplasia- or cancer-derived fibroblasts with gastroids showing the characteristics of spasmolytic polypeptide-expressing metaplasia-induced disordered growth, loss of metaplastic markers, and increases in markers of dysplasia. Culture of metaplastic gastroids with conditioned media from metaplasia- or cancer-derived fibroblasts also promoted dysplastic transition. CONCLUSIONS: These findings indicate that fibroblast associations with metaplastic epithelial cells can facilitate direct transition of metaplastic spasmolytic polypeptide-expressing metaplasia cell lineages into dysplastic lineages.

Hepatitis D virus (HDV) prevalence in Austria is low but causes considerable morbidity due to fast progression to cirrhosis.

BACKGROUND: Hepatitis D virus (HDV) coinfection aggravates the course of hepatitis B virus (HBV). The prevalence of HDV in Austria is unknown. OBJECTIVE: This national study aimed at (i) recording the prevalence of HDV-infection in Austria and (ii) characterizing the "active" HDV cohort in Austria. METHODS: A total of 10 hepatitis treatment centers in Austria participated in this multicenter study and retrospectively collected their HDV patients between Q1/2010 and Q4/2020. Positive anti-HDV and/or HDV-RNA-polymerase chain reaction (PCR) results were retrieved from local database queries. Disease severity was assessed by individual chart review. Viremic HDV patients with clinical visits in/after Q1/2019 were considered as the "active" HDV cohort. RESULTS: A total of 347 anti-HDV positive patients were identified. In 202 (58.2%) patients, HDV-RNA-PCR test was performed, and 126/202 (62.4%) had confirmed viremia. Hepatocellular carcinoma was diagnosed in 7 (5.6%) patients, 7 (5.6%) patients underwent liver transplantation, and 11 (8.7%) patients died during follow-up. The "active" Austrian HDV cohort included 74 (58.7%) patients: Evidence for advanced chronic liver disease (ACLD, i.e., histological F3/F4 fibrosis, liver stiffness ≥10 kPa, varices, or hepatic venous pressure gradient ≥6 mmHg) was detected in 38 (51.4%) patients, including 2 (5.3%) with decompensation (ascites/hepatic encephalopathy). About 37 (50.0%) patients of the "active" HDV cohort had previously received interferon treatment. Treatment with the sodium-taurocholate cotransporting polypeptide inhibitor bulevirtide was initiated in 20 (27.0%) patients. CONCLUSION: The number of confirmed HDV viremic cases in Austria is low (<1% of HBV patients) but potentially underestimated. Testing all HBV patients will increase the diagnostic yield. More than half of viremic HDV patients had ACLD. Improved HDV testing and workup strategies will facilitate access to novel antiviral therapies.

Liver-related Mortality is Increased in Lean Subjects with Non- alcoholic Fatty Liver Disease Compared to Overweight and Obese Subjects.

BACKGROUND AND AIMS: Although non-alcoholic fatty liver disease (NAFLD) is linked to obesity, a proportion of lean subjects also have NAFLD with potentially distinct clinical features. We studied the outcome of lean NAFLD subjects. METHODS: 299 consecutive patients (215 male, 84 female, 49.5 ± 13.5years) with biopsy-proven NAFLD and a follow-up of 8.4 years (±4.1; range: 0.9-18.0) were stratified by body mass index (BMI) at the time of liver biopsy: lean (BMI ≤25.0 kg/m, n=38), overweight (BMI 25.0-29.9 kg/m2, n=165), obese (BMI ≥30.0 kg/m2, n=93). A control group of 1,013 subjects (547 male, 52.4 ± 5.8) was used for comparison. The time to the event was recorded. Multivariable Cox regression analyses were performed to assess associations with 10-year-mortality. Hazard ratios (HR) and adjusted hazard ratios (aHR) with 95% confidence intervals (CI) were calculated. RESULTS: Age and gender were similar, while components of the metabolic syndrome were less frequent in lean subjects. The proportion of subjects with significant fibrosis and the number of subjects with cirrhosis was increased in lean subjects while the proportion of non-alcoholic steatohepatitis was not different. Mortality in the NAFLD groups was significantly higher than in the control group. Multivariable analysis adjusting for age, gender, and glucose confirmed lower mortality in overweight (aHR 0.21; 95% CI 0.07-0.62, p=0.005) and in obese (aHR 0.22; 95% CI 0.06-0.76, p=0.02) compared to lean subjects. Further adjustment for fibrosis weakened the difference between lean and obese (p=0.12) while the difference to overweight subjects remained intact (p=0.01). CONCLUSION: Lean subjects with NAFLD have a high risk of liver-related death. Our data support that lean NAFLD subjects deserve particular attention with regard to clinical follow-up.

Mesenchymal iron deposition is associated with adverse long-term outcome in non-alcoholic fatty liver disease.

BACKGROUND & AIMS: Approximately one-third of patients with non-alcoholic fatty liver disease (NAFLD) show signs of mild-to-moderate iron overload. The impact of histological iron deposition on the clinical course of patients with NAFLD has not been established. METHODS & RESULTS: For this retrospective study, 299 consecutive patients with biopsy-proven NAFLD and a mean follow-up of 8.4 (±4.1; range: 0.3-18.0) years were allocated to one of four groups according to presence of hepatic iron in the reticuloendothelial system (RES) and/or hepatocytes (HC): 156 subjects (52%) showed no stainable iron (NONE), 58 (19%) exclusively reticuloendothelial (xRES), 19 (6%) exclusively hepatocellular (xHC) and 66 (22%) showed a mixed (HC/RES) pattern of iron deposition. A long-term analysis for overall survival, hepatic, cardiovascular or extrahepatic-malignant events was conducted. Based on multivariate Cox proportional hazards models any reticuloendothelial iron was associated with fatal and non-fatal hepatic events. Specifically, xRES showed a cause-specific hazard ratio (csHR) of 2.4 (95%-CI, 1.0-5.8; P = .048) for hepatic as well as cardiovascular fatal and non-fatal events combined (csHR 3.2; 95%-CI, 1.2-8.2; P = .015). Furthermore, the mixed HC/RES iron pattern showed a higher rate of combined hepatic fatal and non-fatal events (csHR 3.6; 95%-CI, 1.4-9.5; P = .010), while xHC iron deposition was not associated with any defined events. CONCLUSIONS: The presence of reticuloendothelial-accentuated hepatic iron distribution patterns is associated with detrimental long-term outcomes reflected in a higher rate of both liver-related and cardiovascular fatal and non-fatal events.

Cancer cell population growth kinetics at low densities deviate from the exponential growth model and suggest an Allee effect.

Most models of cancer cell population expansion assume exponential growth kinetics at low cell densities, with deviations to account for observed slowing of growth rate only at higher densities due to limited resources such as space and nutrients. However, recent preclinical and clinical observations of tumor initiation or recurrence indicate the presence of tumor growth kinetics in which growth rates scale positively with cell numbers. These observations are analogous to the cooperative behavior of species in an ecosystem described by the ecological principle of the Allee effect. In preclinical and clinical models, however, tumor growth data are limited by the lower limit of detection (i.e., a measurable lesion) and confounding variables, such as tumor microenvironment, and immune responses may cause and mask deviations from exponential growth models. In this work, we present alternative growth models to investigate the presence of an Allee effect in cancer cells seeded at low cell densities in a controlled in vitro setting. We propose a stochastic modeling framework to disentangle expected deviations due to small population size stochastic effects from cooperative growth and use the moment approach for stochastic parameter estimation to calibrate the observed growth trajectories. We validate the framework on simulated data and apply this approach to longitudinal cell proliferation data of BT-474 luminal B breast cancer cells. We find that cell population growth kinetics are best described by a model structure that considers the Allee effect, in that the birth rate of tumor cells increases with cell number in the regime of small population size. This indicates a potentially critical role of cooperative behavior among tumor cells at low cell densities with relevance to early stage growth patterns of emerging and relapsed tumors.

Lean Patients with Non-Alcoholic Fatty Liver Disease Have a Severe Histological Phenotype Similar to Obese Patients.

A small proportion of lean patients develop non-alcoholic fatty liver disease (NAFLD). We aimed to report the histological picture of lean NAFLD in comparison to overweight and obese NAFLD patients. Biopsy and clinical data from 466 patients diagnosed with NAFLD were stratified to groups according to body mass index (BMI): lean (BMI ≤ 25.0 kg/m², n confirmed to be appropriate = 74), overweight (BMI > 25.0 ≤ 30.0 kg/m², n = 242) and obese (BMI > 30.0 kg/m², n = 150). Lean NAFLD patients had a higher rate of lobular inflammation compared to overweight patients (12/74; 16.2% vs. 19/242; 7.9%; p = 0.011) but were similar to obese patients (25/150; 16.7%). Ballooning was observed in fewer overweight patients (38/242; 15.7%) compared to lean (19/74; 25.7%; p = 0.014) and obese patients (38/150; 25.3%; p = 0.006). Overweight patients had a lower rate of portal and periportal fibrosis (32/242; 13.2%) than lean (19/74; 25.7%; p = 0.019) and obese patients (37/150; 24.7%; p = 0.016). The rate of cirrhosis was higher in lean patients (6/74; 8.1%) compared to overweight (4/242; 1.7%; p = 0.010) and obese patients (3/150; 2.0% p = 0.027). In total, 60/466; 12.9% patients were diagnosed with non-alcoholic steatohepatitis (NASH). The rate of NASH was higher in lean (14/74; 18.9% p = 0.01) and obese (26/150; 17.3%; p = 0.007) compared to overweight patients (20/242; 8.3%)). Among lean patients, fasting glucose, INR and use of thyroid hormone replacement therapy were independent predictors of NASH in a multivariate model. Lean NAFLD patients were characterized by a severe histological picture similar to obese patients but are more progressed compared to overweight patients. Fasting glucose, international normalized ratio (INR) and the use of thyroid hormone replacement may serve as indicators for NASH in lean patients.

Lineage marker synchrony in hematopoietic genealogies refutes the PU.1/GATA1 toggle switch paradigm.

Molecular regulation of cell fate decisions underlies health and disease. To identify molecules that are active or regulated during a decision, and not before or after, the decision time point is crucial. However, cell fate markers are usually delayed and the time of decision therefore unknown. Fortunately, dividing cells induce temporal correlations in their progeny, which allow for retrospective inference of the decision time point. We present a computational method to infer decision time points from correlated marker signals in genealogies and apply it to differentiating hematopoietic stem cells. We find that myeloid lineage decisions happen generations before lineage marker onsets. Inferred decision time points are in agreement with data from colony assay experiments. The levels of the myeloid transcription factor PU.1 do not change during, but long after the predicted lineage decision event, indicating  that the PU.1/GATA1 toggle switch paradigm cannot explain the initiation of early myeloid lineage choice.

Long-term follow-up of ribavirin-free DAA-based treatment in HCV recurrence after orthotopic liver transplantation.

BACKGROUND & AIMS: Excellent efficacy and safety profile of second-generation DAA combinations improved treatment of chronic hepatitis C (HCV) as well as in HCV recurrence after orthotopic liver transplantation (OLT). The need of ribavirin addition is under debate as anaemia and decreased renal function are prevalent in transplant cohorts. The aim of this study was thus to assess safety and long-term efficacy of RBV-free DAA combinations in HCV-recurrent patients after OLT. PATIENTS & METHODS: A total of 62 OLT recipients (male: 50%/81%; age: 60.7 ± 8.5 years [mean ± SD]; GT - 1: 48, GT - 3: 9, GT - 4: 5; cirrhosis: 34%/55% [7%/21% decompensated], fibrosing cholestatic hepatitis: 1%/2%) received RBV-free treatment with second-generation DAA combinations: sofosbuvir (SOF)/daclatasvir (DCV): 42%/68%, SOF/simeprevir (SMV): 10%/16%, SOF/ledipasvir (LDV): 6%/10% and PrOD: 4%/7%. RESULTS: Data of at least 96 weeks of FUP after treatment cessation (mean: 120; up to 167 weeks) were analysed. All patients showed on-treatment response. By intention-to-treat (ITT) analysis, SVR12 was 97% (60/62, GT-1a: 11/11 [100%]; 1b: 33/34 [97%]; 1g: 1/1 [100%]; subtype not specified: 2/2 [100%]; GT3a: 9/9 [100%]; GT4: 4/5 [80%]) compared to SVR96 of 89% (55/62). No late relapses occurred. In total, 16 severe adverse events occurred, including two newly diagnosed carcinoma (lung cancer, hepatocellular carcinoma). Six patients died; one at treatment week 24 (HCV-RNA undetectable) and five during treatment-free FUP and after achieving SVR (SVR4: N = 1, SVR12: N = 3, after SVR96: N = 1 respectively). Reasons for death were: multi-organ failure (N = 4), impaired graft function (N = 1) and unknown (N = 1). CONCLUSION: RBV-free DAA combinations for the treatment of HCV recurrence after OLT are highly efficacious and well tolerated. Our long-term data show that viral eradication is durable but not necessarily translated into beneficial long-term clinical outcome.

Follow-up of sustained virological responders with hepatitis C and advanced liver disease after interferon/ribavirin-free treatment.

BACKGROUND: The introduction of direct-acting antivirals (DAA) has increased sustained virological response (SVR) rates in patients with advanced liver disease and chronic hepatitis C(CHC)infection. At present, data on clinical outcome and long-term durability of viral eradication after successful DAA therapy are scarce. AIM: To evaluate the long-term success of viral eradication in patients with advanced fibrosis or cirrhosis treated with DAAs. METHODS: Five hundred and fifty-one patients with advanced fibrosis (n = 158) or cirrhosis (CPS-A:317,CPS-B/C:76) and SVR after interferon and ribavirin-free DAA therapy treated between October 2013 and April 2016 were studied with a median follow-up of 65.6 (13.0-155.3) weeks. Only patients without hepatocellular carcinoma (HCC) at baseline and without liver transplantation were included. RESULTS: Twelve patients (2.2%) died during follow-up: the mortality rate was 0.6% in F3, 2.2% in CPS-A and 5.3% in CPS-B/C patients (P = .08). During follow-up 36 patients with cirrhosis (9.1%) developed a liver related event, including 16 with de-novo HCC (4.1%). Seven patients were transplanted at a median of 9.7 (range 3.8-21.7) months after EOT. History of decompensation was significantly associated with liver related events during follow-up (HR 7.9; 95% CI 2.7-22.6; P < .001), and with mortality (HR 5.5; 95% CI 1.5-20.2, P = .01). CONCLUSIONS: Eradication of HCV by DAA therapy was durable irrespective of the DAA combination used. Most of the cured patients had an excellent long-term clinical prognosis. Nevertheless, the risk of new occurrence of HCC remains worrisome and thus regular surveillance is obligatory even after clinical stabilization and improvement of the patient.

Prospective identification of hematopoietic lineage choice by deep learning.

Differentiation alters molecular properties of stem and progenitor cells, leading to changes in their shape and movement characteristics. We present a deep neural network that prospectively predicts lineage choice in differentiating primary hematopoietic progenitors using image patches from brightfield microscopy and cellular movement. Surprisingly, lineage choice can be detected up to three generations before conventional molecular markers are observable. Our approach allows identification of cells with differentially expressed lineage-specifying genes without molecular labeling.

Metabolomic profiling identifies potential pathways involved in the interaction of iron homeostasis with glucose metabolism.

OBJECTIVE: Elevated serum ferritin has been linked to type 2 diabetes (T2D) and adverse health outcomes in subjects with the Metabolic Syndrome (MetS). As the mechanisms underlying the negative impact of excess iron have so far remained elusive, we aimed to identify potential links between iron homeostasis and metabolic pathways. METHODS: In a cross-sectional study, data were obtained from 163 patients, allocated to one of three groups: (1) lean, healthy controls (n = 53), (2) MetS without hyperferritinemia (n = 54) and (3) MetS with hyperferritinemia (n = 56). An additional phlebotomy study included 29 patients with biopsy-proven iron overload before and after iron removal. A detailed clinical and biochemical characterization was obtained and metabolomic profiling was performed via a targeted metabolomics approach. RESULTS: Subjects with MetS and elevated ferritin had higher fasting glucose (p < 0.001), HbA1c (p = 0.035) and 1 h glucose in oral glucose tolerance test (p = 0.002) compared to MetS subjects without iron overload, whereas other clinical and biochemical features of the MetS were not different. The metabolomic study revealed significant differences between MetS with high and low ferritin in the serum concentrations of sarcosine, citrulline and particularly long-chain phosphatidylcholines. Methionine, glutamate, and long-chain phosphatidylcholines were significantly different before and after phlebotomy (p < 0.05 for all metabolites). CONCLUSIONS: Our data suggest that high serum ferritin concentrations are linked to impaired glucose homeostasis in subjects with the MetS. Iron excess is associated to distinct changes in the serum concentrations of phosphatidylcholine subsets. A pathway involving sarcosine and citrulline also may be involved in iron-induced impairment of glucose metabolism.

Early myeloid lineage choice is not initiated by random PU.1 to GATA1 protein ratios.

The mechanisms underlying haematopoietic lineage decisions remain disputed. Lineage-affiliated transcription factors with the capacity for lineage reprogramming, positive auto-regulation and mutual inhibition have been described as being expressed in uncommitted cell populations. This led to the assumption that lineage choice is cell-intrinsically initiated and determined by stochastic switches of randomly fluctuating cross-antagonistic transcription factors. However, this hypothesis was developed on the basis of RNA expression data from snapshot and/or population-averaged analyses. Alternative models of lineage choice therefore cannot be excluded. Here we use novel reporter mouse lines and live imaging for continuous single-cell long-term quantification of the transcription factors GATA1 and PU.1 (also known as SPI1). We analyse individual haematopoietic stem cells throughout differentiation into megakaryocytic-erythroid and granulocytic-monocytic lineages. The observed expression dynamics are incompatible with the assumption that stochastic switching between PU.1 and GATA1 precedes and initiates megakaryocytic-erythroid versus granulocytic-monocytic lineage decision-making. Rather, our findings suggest that these transcription factors are only executing and reinforcing lineage choice once made. These results challenge the current prevailing model of early myeloid lineage choice.

Natural course of subjects with elevated liver tests and normal liver histology.

BACKGROUND & AIMS: Liver biopsy (LB) is performed if non-invasive work-up of liver disease is inconclusive. The examination of liver tissue occasionally reveals normal histology. Long-term follow-up of such patients has not been performed. METHODS: We identified a total 70 subjects from our LB database with elevated liver tests and normal liver histology after a mean of 90.5 ± 52.3 (range 15-216) months and conducted reassessment of medical history, physical examination, laboratory testing, ultrasound, transient elastography and LB if indicated. RESULTS: At follow-up examination, 15 (7 females (f)/8 males (m); 21.4%) subjects had normal liver tests and no further evidence of liver disease. A subset of 37 (29 f/8 m; 52.9%) subjects had persistently elevated liver tests without evidence indicating progressive liver disease but the cause thereof remained unexplained also at the follow-up visit. Three (0 f/3 m; 4.3%) subjects had consumed excessive alcohol with indicators of alcoholic liver disease. Eleven subjects (4 f/7 m; 15.7%) had developed steatosis on ultrasound examination along with weight gain and/or biochemical features of the metabolic syndrome. In addition, three (2 f/1 m) patients developed autoimmune hepatitis, one female presented with primary biliary cirrhosis. One male was diagnosed with cholangiocellular carcinoma 3 months after the initial evaluation. CONCLUSION: The clinical course of most patients was benign, but in approximately 20% of the subjects a liver disease developed. Particular attention should be given to autoimmune liver diseases in subjects with positive autoantibodies. In addition, lifestyle factors such as weight gain and alcohol consumption were associated with the manifestation of liver diseases.

Hepatic steatosis in Wilson disease--Role of copper and PNPLA3 mutations.

BACKGROUND & AIMS: The earliest characteristic alterations of the liver pathology in Wilson disease (WD) include steatosis, which is sometimes indistinguishable from non-alcoholic fatty liver disease (NAFLD). Steatosis in WD may reflect copper-induced mitochondrial dysfunction. A genetic polymorphism in rs738409, in the patatin-like phospholipase domain-containing 3 gene (PNPLA3), is strongly associated with appearance of in NAFLD. This study evaluated the role of PNPLA3 and hepatic copper content for development of steatosis in patients with WD. METHODS: Liver biopsies obtained at diagnosis and the PNPLA3 genotype were analyzed in 98 Caucasian patients with WD (male: 52 [53.1%]; mean age: 27.6 years [CI 95%: 24.8-30.4, range: 5.8-61.5]). Steatosis was graded as percentage of lipid containing hepatocytes by an expert hepatopathologist unaware of the results of genetic testing. RESULTS: Moderate/severe steatosis (>33% of hepatocytes) was observed in 28 patients (pediatric: n=13/26 [50.0%], adult: n=15/72 [20.8%]; p=0.01). Forty-six patients (46.9%; pediatric: n=7, adult: n=39; p=0.022) had cirrhosis. Multivariate logistic regression identified PNPLA3 G allele (OR: 2.469, CI 95%: 1.203-5.068; p=0.014) and pediatric age (OR: 4.348; 1.577-11.905; p=0.004) as independent variables associated with moderate/severe steatosis. In contrast, hepatic copper content did not impact on moderate/severe steatosis (OR: 1.000, CI 95%: 1.000-1.001; p=0.297). CONCLUSIONS: Steatosis is common in WD and the PNPLA3 G allele contributes to its pathogenesis. The role of hepatic copper concentration and ATP7B mutations in steatosis development deserve further investigations.

Liver toxicity during temozolomide chemotherapy caused by Chinese herbs.

BACKGROUND: Complementary and alternative medicine is often used by patients with malignant glioma. Although several interactions of various alternative agents with chemotherapy are known, none has been described for temozolomide so far. CASE PRESENTATION: We report the case of severe liver toxicity with jaundice during radiochemotherapy with temozolomide likely due to interaction with a popular Chinese herbal formula after surgery for glioblastoma. After cessation of the herbal formula as well as the chemotherapy liver enzymes slowly normalized. Due to tumor progression the patient was retreated with temozolomide for 5 cycles without toxicity. Because of further progression combination treatment of bevacizumab and irinotecan was started and again no liver toxicity was observed. CONCLUSIONS: We conclude that the observed toxicity with jaundice was probably caused by an interaction of this popular Chinese formula and temozolomide. This is the first report about a relevant interaction of temozolomide and any herbal formula.

Evaluation of genome-wide loci of iron metabolism in hereditary hemochromatosis identifies PCSK7 as a host risk factor of liver cirrhosis.

Genome-wide association studies (GWAS) have revealed genetic determinants of iron metabolism, but correlation of these with clinical phenotypes is pending. Homozygosity for HFE C282Y is the predominant genetic risk factor for hereditary hemochromatosis (HH) and may cause liver cirrhosis. However, this genotype has a low penetrance. Thus, detection of yet unknown genetic markers that identify patients at risk of developing severe liver disease is necessary for better prevention. Genetic loci associated with iron metabolism (TF, TMPRSS6, PCSK7, TFR2 and Chr2p14) in recent GWAS and liver fibrosis (PNPLA3) in recent meta-analysis were analyzed for association with either liver cirrhosis or advanced fibrosis in 148 German HFE C282Y homozygotes. Replication of associations was sought in additional 499 Austrian/Swiss and 112 HFE C282Y homozygotes from Sweden. Only variant rs236918 in the PCSK7 gene (proprotein convertase subtilisin/kexin type 7) was associated with cirrhosis or advanced fibrosis (P = 1.02 × 10(-5)) in the German cohort with genotypic odds ratios of 3.56 (95% CI 1.29-9.77) for CG heterozygotes and 5.38 (95% CI 2.39-12.10) for C allele carriers. Association between rs236918 and cirrhosis was confirmed in Austrian/Swiss HFE C282Y homozygotes (P = 0.014; ORallelic = 1.82 (95% CI 1.12-2.95) but not in Swedish patients. Post hoc combined analyses of German/Swiss/Austrian patients with available liver histology (N = 244, P = 0.00014, ORallelic = 2.84) and of males only (N = 431, P = 2.17 × 10(-5), ORallelic = 2.54) were consistent with the premier finding. Association between rs236918 and cirrhosis was not confirmed in alcoholic cirrhotics, suggesting specificity of this genetic risk factor for HH. PCSK7 variant rs236918 is a risk factor for cirrhosis in HH patients homozygous for the HFE C282Y mutation.

Role of FDFT1 polymorphism for fibrosis progression in patients with chronic hepatitis C.

BACKGROUND: In chronic hepatitis C (CHC), steatosis is associated with fibrosis and impaired response to antiviral therapy. Recently, a polymorphism of single nucleotide polymorphism SNP rs2645424 of farnesyl diphosphate farnesyl transferase 1 (FDFT1) was identified in NAFLD/NASH as a possible causal link to steatosis and fibrosis progression. SNP rs738409 in the adiponutrin gene (PNPLA3) is a well described factor for steatosis. This study evaluated the relation of these SNPs on steatosis, fibrosis and treatment response in CHC. METHODS: The SNPs rs738409478 and rs2645424 were determined by real-time PCR in 478 patients with CHC (m/f: 314/164; mean age: 44.9 ± 10.7; GT1: 387, GT4: 91) who completed treatment with peg-IFN-α-2a/ribavirin. All had a pretreatment liver biopsy. Steatosis and fibrosis were graded by board-certified pathologists according to Brunt and METAVIR respectively. RESULTS: The distribution of FDFT1 rs2645424 was GG: 186 (38.9%), AG: 222 (46.4%) and AA: 70 (14.6%) and of the rs738409 PNPLA3 allele: CC: 269 (56.3%), CG: 177 (37.0%) and GG: 32 (6.7%). Overall, FDTF1 polymorphism was not linked to the extent of steatosis or fibrosis. However, in patients without steatosis the AA genotype was associated with advanced fibrosis [AA: 8/20 (40.0%), AG: 6/70 (8.5%), GG: 9/57 (16.1%), P = 0.003]. In contrast, the minor PNPLA3 allele was associated with both steatosis and advanced fibrosis (P < 0.001). Both SNPs did not influence treatment response. CONCLUSION: The minor allele in FDFT1 was associated with advanced fibrosis in the non-steatotic but not in the steatotic subgroup. This may reflect different metabolic pathways in fibrosis progression for steatotic and non-steatotic patients with CHC.