CpG site methylation of HCV-cirrhotic, HCV-HCC, and normal liver tissues
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ABSTRACT: In this study we used a high-throughput method for assaying methylation of CpG sites simultaneously in a single sample for identifying differences in methylation observed in tissues ranging from normal liver to pre-neoplastic (cirrhosis) and neoplastic (HCC) states. Since there are important clinical and prognostic differences among HCC patients due to etiology, this study was designed to focus on HCC due to HCV-infection, a more common etiology of HCC among Western countries cross-sectional: 20 cirrhosis, 20 HCC, and 16 normal patients, 87 arrays
Project description:In this study we used a high-throughput method for assaying methylation of CpG sites simultaneously in a single sample for identifying differences in methylation observed in tissues ranging from normal liver to pre-neoplastic (cirrhosis) and neoplastic (HCC) states. Since there are important clinical and prognostic differences among HCC patients due to etiology, this study was designed to focus on HCC due to HCV-infection, a more common etiology of HCC among Western countries
Project description:In this study we used a high-throughput method for assaying methylation of CpG sites simultaneously in a single sample for identifying differences in methylation observed in tissues ranging from normal liver to pre-neoplastic (cirrhosis) and neoplastic (HCC) states. Since there are important clinical and prognostic differences among HCC patients due to etiology, this study was designed to focus on HCC due to HCV-infection, a more common etiology of HCC among Western countries cross-sectional: 20 cirrhosis, 20 HCC, and 16 normal patients, 87 arrays
Project description:Progression from chronic hepatitis C virus (HCV) infection to cirrhosis and hepatocellular carcinoma (HCC) results in protein changes in the peripheral blood. We evaluated global protein expression in plasma samples of HCV-cirrhotic and HCV-cirrhotic-HCC patients.Plasma samples from 25 HCV-cirrhotic-HCC and 10 HCV-cirrhotic patients were quantitatively evaluated for protein expression. Tryptic peptides were analyzed using Thermo linear ion-trap mass spectrometer (LTQ) coupled with a Surveyor HPLC system (Thermo). SEQUEST and X!Tandem database search algorithms were used for peptide sequence identification. Protein relative quantification was performed using the area under the curve from the select ion chromatogram. A significant fold change between groups was based on controlling the false discovery rate (FDR) at less than 5%.We identified and quantified 2320 proteins from the analysis of the different protein pattern between HCV-cirrhosis and HCV-HCC samples. Gene ontology terms classified the more important biologic process related to these proteins as signal transduction, regulation of transcription DNA-dependent, protein amino acid phosphorylation, cell adhesion, transport, and immune response. Seven proteins showed significant expression changes with a FDR less than 5% between cirrhosis and tumor groups. Moreover, 18 proteins showed significant expression changes (FDR <5%) when plasma samples from HCV-cirrhosis were compared with early HCV-HCC.Differential protein expression was observed between samples from HCV patients with cirrhosis with and without HCC. Also, differences were observed between early and advanced HCV-HCC samples. This study provides important information for discovery of potential biomarkers for early HCC diagnosis in HCV cirrhotic patients.
Project description:Prospective studies on predictors of liver-related events in cirrhotic subjects achieving SVR after DAAs are lacking. We prospectively enrolled HCV cirrhotic patients in four Italian centers between November 2015 and October 2017. SVR and no-SVR cases were compared according to the presence or absence of liver-related events during a 24-month follow-up. Independent predictors of liver-related events were evaluated by Cox regression analysis. A total of 706 subjects started DAAs therapy. SVR was confirmed in 687 (97.3%). A total of 61 subjects (8.9%) in the SVR group and 5 (26.3%) in the no-SVR group had liver-related events (p < 0.03). The incidence rate x 100 p/y was 1.6 for HCC, 1.7 for any liver decompensation, and 0.5 for hepatic death. Baseline liver stiffness (LSM) ≥ 20 kPa (HR 4.0; 95% CI 1.1-14.1) and genotype different from 1 (HR 7.5; 95% CI 2.1-27.3) were both independent predictors of liver decompensation. Baseline LSM > 20 KPa (HR 7.2; 95% CI 1.9-26.7) was the sole independent predictor of HCC. A decrease in liver stiffness (Delta LSM) by at least 20% at the end of follow-up was not associated with a decreased risk of liver-related events. Baseline LSM ≥ 20 kPa identifies HCV cirrhotic subjects at higher risk of liver-related events after SVR.
Project description:Methylation of promoter CpG islands has been associated with gene silencing and demonstrated to lead to chromosomal instability. Therefore, some postulate that aberrantly methylated CpG regions may be important biomarkers indicative of cancer development. In this study we used the Illumina GoldenGate Methylation BeadArray Cancer Panel I for simultaneously profiling methylation of 1,505 CpG sites in order to identify methylation differences in 76 liver tissues ranging from normal to pre-neoplastic and neoplastic states. CpG sites for ESR1, GSTM2, and MME were significantly differentially methylated when comparing the pre-neoplastic tissues from patients with concomitant hepatocellular carcinoma (HCC) to the pre-neoplastic tissues from patients without HCC. When comparing paired HCC tissues to their corresponding pre-neoplastic non-tumorous tissues, eight CpG sites, including one CpG site that was hypermethylated (APC) and seven (NOTCH4, EMR3, HDAC9, DCL1, HLA-DOA, HLA-DPA1, and ERN1) that were hypomethylated in HCC, were identified. Our study demonstrates that high-throughput methylation technologies may be used to identify differentially methylated CpG sites that may prove to be important molecular events involved in carcinogenesis.
Project description:The role of chronic hepatitis C virus (HCV) in the pathogenesis of HCV-associated hepatocellular carcinoma (HCC) is not completely understood, particularly at the molecular level. We studied gene expression in normal, pre-malignant (cirrhosis), and tumor (HCC) liver tissues using Affymetrix GeneChips. Keywords: cross-sectional
Project description:DNA methylation alterations are related to multiple molecular mechanisms. The DNA context of CpG sites plays a crucial role in the maintenance and stability of methylation patterns. The quantitative relationship between DNA composition and DNA methylation has been studied in normal as well as pathological conditions, showing that DNA methylation status is highly dependent on the local sequence context. In this work, we describe this relationship by analyzing the DNA sequence context associated to methylation profiles in both physiological and pathological conditions. In particular, we used DNA motifs to describe methylation stability patterns in normal tissues and aberrant methylation events in cancer lesions. In this manuscript, we show how different groups of DNA sequences can be related to specific epigenetic events, across normal and cancer tissues, and provide a thorough structural and functional characterization of these sequences.
Project description:Although most CpG islands are generally thought to remain unmethylated in all adult somatic tissues, recent genome-wide approaches have found that some CpG islands have distinct methylation patterns in various tissues, with most differences being seen between germ cells and somatic tissues. Few studies have addressed this among human somatic tissues and fewer still have studied the same sets of tissues from multiple individuals. In the current study, we used Restriction Landmark Genomic Scanning to study tissue specific methylation patterns in a set of twelve human tissues collected from multiple individuals. We identified 34 differentially methylated CpG islands among these tissues, many of which showed consistent patterns in multiple individuals. Of particular interest were striking differences in CpG island methylation, not only among brain regions, but also between white and grey matter of the same region. These findings were confirmed for selected loci by quantitative bisulfite sequencing. Cluster analysis of the RLGS data indicated that several tissues clustered together, but the strongest clustering was in brain. Tissues from different brain regions clustered together, and, as a group, brain tissues were distinct from either mesoderm or endoderm derived tissues which demonstrated limited clustering. These data demonstrate consistent tissue specific methylation for certain CpG islands, with clear differences between white and grey matter of the brain. Furthermore, there was an overall pattern of tissue specifically methylated CpG islands that distinguished neural tissues from non-neural.