Project description:Purpose: To gain molecular insights of HBV integration that may contribute to HCC tumorigenesis, we performed whole transcriptome sequencing and whole genome copy number profiling of hepatocellular carcinoma (HCC) samples from 50 Chinese patients. Conclusions: This is the first report on the molecular basis of the MLL4 integration driving MLL4 over-expression. HBV-MLL4 integration occurred frequently in Chinese HCC patients, representing a unique molecular segment for HCC with HBV infection.
Project description:Purpose: To gain molecular insights of HBV integration that may contribute to HCC tumorigenesis, we performed whole transcriptome sequencing and whole genome copy number profiling of hepatocellular carcinoma (HCC) samples from 50 Chinese patients. Conclusions: This is the first report on the molecular basis of the MLL4 integration driving MLL4 over-expression. HBV-MLL4 integration occurred frequently in Chinese HCC patients, representing a unique molecular segment for HCC with HBV infection. We profiled 50 Chinese Hepatocellular Carcinoma patients and 14 adjacent tissues using Agilent 244K array CGH technology. 50 Tumor samples also did RNASeq profiling.
Project description:Purpose: To gain molecular insights of HBV integration that may contribute to HCC tumorigenesis, we performed whole transcriptome sequencing and whole genome copy number profiling of hepatocellular carcinoma (HCC) samples from 50 Chinese patients. Results: We identified a total of 33 HBV-human integration sites in 16 of 44 HBV-positive HCC tissues, which were enriched in HBV genotype C-infected patients. In addition, significantly recurrent HBV-MLL4 integration (18%; 8/44) was found in this cohort of patients. Conclusions: This is the first report on the molecular basis of the MLL4 integration driving MLL4 over-expression. HBV-MLL4 integration occurred frequently in Chinese HCC patients, representing a unique molecular segment for HCC with HBV infection.
Project description:Purpose: To gain molecular insights of HBV integration that may contribute to HCC tumorigenesis, we performed whole transcriptome sequencing and whole genome copy number profiling of hepatocellular carcinoma (HCC) samples from 50 Chinese patients. Results: We identified a total of 33 HBV-human integration sites in 16 of 44 HBV-positive HCC tissues, which were enriched in HBV genotype C-infected patients. In addition, significantly recurrent HBV-MLL4 integration (18%). This dataset is part of the TransQST collection.
Project description:Hepatitis B virus (HBV) mutations promote the occurrence of hepatocellular carcinoma (HCC). However, their association with postoperative prognosis remains obscure. Here, we aimed to characterize the evolution of HBV in different sources and identify viral mutation pattern that facilitates postoperative prognosis of HCC.
Project description:BACKGORUND & AIMS: Hepatocellular carcinoma (HCC) disproportionally affects Asian Americans due to the high prevalence of chronic hepatitis B virus (HBV) infection and among Asian ethnic groups. The Hmong are diagnosed with HCC at a younger age, with more advanced stage disease, and have the highest cause specific mortality of any Asian ethnic group. Poor survival from HCC has also been associated with differential gene expression in HCC tumors leading us to hypothesize that quantitative traits loci lead to differences in the expression of genes in Hmong which reduce their HCC survival. METHODS: We performed bulk RNA-sequencing of whole blood total RNA from HBV-infected Hmong (n=30) and non-Hmong Asians (Chinese (n=46), and Vietnamese (n=19)). RESULTS: No significant differences between groups were identified in demographic, clinical, or viral factors. A total of 1,491 differentially-expressed transcripts (DETs) were identified across the 3 ethnic groups. When restricted to those with an HBV viral load >2,000 IU/L, 768 DETs were identified and accurately separated individuals by ethincity. Among 273 DETs identified by functional enrichment and pathway analysis and associated with annotated sets of HCC-related genes, 9 were found in 2 gene sets highly expressed in HCC with poor survival. After adjusting for age and sex, expression levels of 4 of these, including CD164, ECT2, HDAC2, and UBE2T, remained significantly elevated in Hmong compared to Chinese and Vietnamese. CONCLUSIONS: These results suggest expression quantitative trait loci predispose Hmong to a more agrressive form of HCC and may explain the poor survival among this Asian ethnic group.
Project description:RNA-seq is a powerful tool for comprehensive characterization of whole transcriptome at both gene and exon levels and with a unique ability of identifying novel splicing variants. To date, RNA-seq analysis of HBV-related HCC has not been reported. In this study, we performed transcriptome analyses for 10 matched pairs of cancer and non-cancerous tissues from Chinese HBV-related hepatocelluar carcinoma patients using 36bp single-end sequencing approach on Solexa/Illumina GAII platform. On average, about 21.6 million sequencing reads and 10.6 million aligned reads were obtained for samples sequenced on each lane, which was able to identify > 50% of all the annotated genes for each sample. Furthermore, from by far the largest database of transcripts expressed in HCC tissues, we identified 1,378 significantly differently expressed genes (DEGs) and 24, 338 differentially expressed exons (DEEs). Comprehensive function analyses indicated that cell growth-related, metabolism-related and immune-related pathways were most significantly enriched by DEGs, pointing to a complex mechanism for HCC carcinogenesis. Positional gene enrichment analysis showed that DEGs were most significantly enriched at chromosome 8q21.3-24.3. The most interesting findings were from the analysis at exon levels where we characterized three major patterns of expression changes between gene levels and exon levels, implying a much complex landscape of transcript-specific differential expressions in HCC. Finally, we identified a novel highly up-regulated exon-exon junction in ATAD2 (ATPase family, AAA domain containing 2) gene in HCC tissues. Overall, to our best knowledge, our study represents the most comprehensive characterization of the HBV-related HCC transcriptome including exon level expression changes and novel splicing variants, which illustrated the power of RNA-seq and provided important clues for understanding the molecular mechanisms of HCC pathogenesis at system-wide levels. A comprehensive analysis of transcriptome for 10 match-paired HBV-related Chinese HCC and non-cancerous adjacent tissues. Processed data files: Exon-level results, gene-level results, differentially expressed exons, and differently expressed genes (DEGs).
Project description:The Eastern woodchuck (Marmota monax) is naturally infected with woodchuck hepatitis virus (WHV), a hepadnavirus closely related to the human hepatitis B virus (HBV). The woodchuck is used as an animal model for studying chronic hepatitis B (CHB) and HBV-associated hepatocellular carcinoma (HCC) in humans, but the lack of sequence information has hitherto precluded functional genomics analysis. To address this major limitation of the model, we report here the sequencing, assembly and annotation of the woodchuck transcriptome, together with the generation of custom woodchuck microarrays. Using this new platform, we characterized the transcriptional response to persistent WHV infection and WHV-induced HCC. This revealed that chronic WHV infection, like HBV, is associated with (i) a limited intrahepatic type I interferon response, (ii) intrahepatic induction of markers associated with T cell exhaustion, (iii) elevated levels of suppressor of cytokine signaling 3 (SOCS3) in the liver, and (iv) intrahepatic accumulation of neutrophils. Underscoring the translational value of the woodchuck model, this study also determined that WHV-induced HCC shares molecular characteristics with a subtype of human HCC with poor prognosis. Conclusion: Our data establish the translational value of the woodchuck model and provide new insights into immune pathways which may play a role either in the persistence of HBV infection or the sequelae of CHB. Custom microarrays, generated from sequences obtained in transcriptome sequencing of woodchuck liver and PBMCs, were used to examine non-tumor vs. tumor gene expression in liver samples obtained from animals chronically infected with WHV (n=13). Multiple technical replicates per woodchuck sample are included.
Project description:MicroRNAs (miRNAs) exhibit essential regulatory functions related to cell growth, apoptosis, development and differentiation. Dysregulated expression of miRNAs is associated with a wide variety of human diseases. As such miRNA signatures are valuable as biomarkers for disease and for making treatment decisions. Hepatitis B virus (HBV) is a major risk factor for hepatocellular carcinoma (HCC). Here we screened for miRNAs in chronic HBV associated HCC. To evaluate the effect of HBV infection on the change in expression of miRNAs, 12 pairs of samples from HCC and non-tumor tissues (including 6 HBV-positive HCC and 6 HBV-negative HCC and their non-tumor tissues) were collected. The extracted RNAs were evaluated to detect the expression of miRNAs. Using ANOVA to screen the differential expression of miRNAs at P-value ⤠0.01, fold change ⥠2 or ⤠0.5, 225 miRNAs were detected.
Project description:The molecular mechanisms whereby hepatitis B virus (HBV) induces hepatocellular carcinoma (HCC) remain elusive. We used genomic and molecular techniques to investigate host-virus interactions by mapping the entire liver of patients with HCC. We compared the gene signature of whole liver tissue (WLT) versus laser capture-microdissected (LCM) hepatocytes with intrahepatic expression of HBV. Gene expression profiling was performed on up to 17 WLT specimens obtained at various distances from the tumor center in individual livers of 11 patients with HCC and on selected LCM samples. HBV biomarkers were determined by real-time PCR and confocal immunofluorescence. Analysis of 5 areas of the liver showed a sharp change in gene expression between the immediate perilesional area and tumor periphery that correlated with a significant decrease in the intrahepatic expression of HBsAg. The tumor was characterized by a large preponderance of down-regulated genes, mostly involved in the metabolism of lipid and fatty acid, glucose, amino acids and drugs, with down-regulation of pathways involved in the activation of PXR/RXR and PPARa/RXRa nuclear receptors, comprising PGC1 and FOXO1, two key regulators of the hepatic metabolic functions and HBV transcription. These findings were confirmed by gene expression of microdissected hepatocytes. However, LCM of malignant hepatocytes also revealed up-regulation of unique genes associated with cancer and signaling pathways, including two novel HCC-associated cancer testis antigen (CTA) genes, NUF2 and TTK. HCC-associated with HBV is characterized by a metabolism switch-off and by a significant reduction in HBsAg. LCM proved to be a critical tool to validate gene signatures associated with HCC and to identify genes that may play a role in hepatocarcinogenesis opening new perspectives for the discovery of novel diagnostic markers and therapeutic targets. Samples were obtained at various distances from the tumor center in individual livers of 11 patients with HBV-associated HCC. Whole liver tissue samples were compared to LCM samples of malignant and non-malignant hepatocytes obtained from the same livers. This dataset is part of the TransQST collection.