Our recent progress includes: (1) Cholangiocarcinoma is a heterogeneous disease with a poor outcome that accounts for 5%-10% of primary liver cancers. We characterized its genomic and genetic features and associated these with patient responses to therapy.We profiled the transcriptomes from 104 surgically resected cholangiocarcinoma samples collected from patients in Australia, Europe, and the United States;epithelial and stromal compartments from 23 tumors were laser capture microdissected. We analyzed mutations in KRAS, epidermal growth factor receptor (EGFR), and BRAF in samples from 69 tumors. Changes in gene expression were validated by immunoblotting and immunohistochemistry;integrative genomics combined data from the patients with data from 7 human cholangiocarcinoma cell lines, which were then exposed to trastuzumab and lapatinib. Patients were classified into 2 subclasses, based on 5-year survival rate (72% vs 30%;chi(2) = 11.61;P <.0007), time to recurrence (13.7 vs 22.7 months;P <.001), and the absence or presence of KRAS mutations (24.6%), respectively. Class comparison identified 4 survival subgroups (SGI-IV;chi(2) = 8.34;P <.03);SGIII was characterized by genes associated with proteasomal activity and the worst prognosis. The tumor epithelium was defined by deregulation of the HER2 network and frequent overexpression of EGFR, the hepatocyte growth factor receptor (MET), pRPS6, and Ki67, whereas stroma was enriched in inflammatory cytokines. Lapatinib, an inhibitor of HER2 and EGFR, was more effective in inhibiting growth of cholangiocarcinoma cell lines than trastuzumab. Our data provide insight into the pathogenesis of cholangiocarcinoma and identify previously unrecognized subclasses of patients, based on KRAS mutations and increased levels of EGFR and HER2 signaling, who might benefit from dual-target tyrosine kinase inhibitors. The group of patients with the worst prognosis was characterized by transcriptional enrichment of genes that regulate proteasome activity, indicating new therapeutic targets;(2) Hepatocellular carcinoma (HCC) is an aggressive malignancy;its mechanisms of development and progression are poorly understood. We used an integrative approach to identify HCC driver genes, defined as genes whose copy numbers associate with gene expression and cancer progression. We combined data from high-resolution, array-based comparative genomic hybridization and transcriptome analysis of HCC samples from 76 patients with hepatitis B virus infection with data on patient survival times. Candidate genes were functionally validated using in vitro and in vivo models. Unsupervised analyses of array comparative genomic hybridization data associated loss of chromosome 8p with poor outcome (reduced survival time);somatic copy number alterations correlated with expression of 27.3% of genes analyzed. We associated expression levels of 10 of these genes with patient survival times in 2 independent cohorts (comprising 319 cases of HCC with mixed etiology) and 3 breast cancer cohorts (637 cases). Among the 10-gene signature, a cluster of 6 genes on 8p, (DLC1, CCDC25, ELP3, PROSC, SH2D4A, and SORBS3) were deleted in HCCs from patients with poor outcomes. In vitro and in vivo analyses indicated that the products of PROSC, SH2D4A, and SORBS3 have tumor-suppressive activities, along with the known tumor suppressor gene DLC1. Here we have used an unbiased approach to identify 10 genes associated with HCC progression. These might be used in assisting diagnosis and to stage tumors based on gene expression patterns;(3)Clinical application of the prognostic gene expression signature has been delayed due to the large number of genes and complexity of prediction algorithms. In the current study we aimed to develop an easy-to-use risk score with a limited number of genes that can robustly predict prognosis of patients with hepatocellular carcinoma (HCC). The risk score was developed using Cox coefficient values of 65 genes in the training set (n = 139) and its robustness was validated in test sets (n = 292). The risk score was a highly significant predictor of overall survival (OS) in the first test cohort (P = 5.6 ? 10(-5), n = 100) and the second test cohort (P = 5.0 ? 10(-5) , n = 192). In multivariate analysis, the risk score was a significant risk factor among clinical variables examined together (hazard ratio [HR], 1.36;95% confidence interval [CI], 1.13-1.64;P = 0.001 for OS). CONCLUSION: The risk score classifier we have developed can identify two clinically distinct HCC subtypes at early and late stages of the disease in a simple and highly reproducible manner across multiple datasets;(4)Gene expression is suppressed by DNA methylation. The goal of this study was to identify genes whose CpG site methylation and mRNA expression are associated with recurrence after surgical resection for hepatocellular carcinoma (HCC). Sixty-two HCCs were examined by both whole genome DNA methylation and transcriptome analysis. The Cox model was used to select genes associated with recurrence. A validation was performed in an independent cohort of 66 HCC patients. Among fifty-nine common genes, increased CpG site methylation and decreased mRNA expression were associated with recurrence for 12 genes (Group A), whereas decreased CpG site methylation and increased mRNA expression were associated with recurrence for 25 genes (Group B). The remaining 22 genes were defined as Group C. Complement factor H (CFH) and myosin VIIA and Rab interacting protein (MYRIP) in Group A;proline/serine-rich coiled-coil 1 (PSRC1), meiotic recombination 11 homolog A (MRE11A), and myosin IE (MYO1E) in Group B;and autophagy-related protein LC3 A (MAP1LC3A), and NADH dehydrogenase 1 alpha subcomplex assembly factor 1 (NDUFAF1) in Group C were validated. In conclusion, potential tumor suppressor (CFH, MYRIP) and oncogenes (PSRC1, MRE11A, MYO1E) in HCC are reported. The regulation of individual genes by methylation in hepatocarcinogenesis needs to be validated.
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