Hepatocellular carcinoma (HCC) has a poor prognosis owing to aggressive phenotype. Gα12 gep oncogene product couples to G-protein-coupled receptors, whose ligand levels are frequently increased in tumor microenvironments. Here, we report Gα12 overexpression in human HCC and the resultant induction of zinc-finger E-box-binding homeobox 1 (ZEB1) as mediated by microRNA deregulation. Gα12 expression was higher in HCC than surrounding non-tumorous tissue. Transfection of Huh7 cell with an activated mutant of Gα12 (Gα12QL) deregulated microRNA (miRNA or miR)-200b/a/429, -194-2/192 and -194-1/215 clusters in the miRNome. cDNA microarray analyses disclosed the targets affected by Gα12 gene knockout. An integrative network of miRNAs and mRNA changes enabled us to predict ZEB1 as a key molecule governed by Gα12. Decreases of miR-200a/b, -192 and -215 by Gα12 caused ZEB1 induction. The ability of Gα12 to decrease p53 levels, as a result of activating protein-1 (AP-1)/c-Jun-mediated mouse double minute 2 homolog induction, contributed to transcriptional deregulation of the miRNAs. Gα12QL induced ZEB1 and other epithelial-mesenchymal transition markers with fibroblastoid phenotype change. Consistently, transfection with miR-200b, -192 or -215 mimic prevented the ability of Gα12QL to increase tumor cell migration/invasion. In xenograft studies, sustained knockdown of Gα12 decreased the overall growth rate and average volume of tumors derived from SK-Hep1 cell (mesenchymal-typed). In HCC patients, miR-192, -215 and/or -200a were deregulated with microvascular invasion or growth advantage. In the HCC samples with higher Gα12 level, a correlation existed in the comparison of relative changes of Gα12 and ZEB1. In conclusion, Gα12 overexpressed in HCC causes ZEB1 induction by deregulating p53-responsive miRNAs, which may facilitate epithelial-mesenchymal transition and growth of liver tumor. These findings highlight the significance of Gα12 upregulation in liver tumor progression, implicating Gα12 as an attractive therapeutic target.

A phase-field model for investigating the surface morphological evolution of a film is developed, taking into account the surface energies of film and substrate, the interfacial energy between the film and substrate, and the elastic energy associated with the lattice mismatch between the film and substrate. Using the lattice mismatch and the surface energies for the Ge/ Si heteroepitaxial system, the morphology of islands and the formation of a wetting layer are investigated using two-dimensional simulations. The results show that the wetting angle increases continuously with the increase in the lattice mismatch, and the surface angle of the island on wetting layer varies with the island size. It is demonstrated that the anisotropy of elastic interactions alone is not sufficient to cause surface angle discontinuity or faceting that is observed in experiments.

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Twenty-five koi (Cyprinus carpio haematopterus) bought from a wholesale fish market in Korea, showed lethargic behaviour and 100% mortality within 20 days. Carp oedema virus (CEV) was detected by PCR in all 25 koi. Results of detailed histopathological and clinical examinations of 17 koi indicated loss of body balance, severe infiltration of inflammatory cells into the inter-lamellar spaces of the gills and vacuolization and inclusion bodies in gill epithelial cells. Sequence analysis of PCR products of these koi showed up to 99% identity to the previously reported sequences, suggesting that the observed mass mortality resulted from koi sleepy disease (KSD) due to CEV infection. To the best of our knowledge, this study is the first report of KSD in the Republic of Korea. Partial sequences of 4a protein from the virus indicated that the present CEV detected in koi from Korea is more closely related to that from the UK and Poland than from Japan. The present findings indicate that the prevalence and spread of KSD must be closely monitored in both European and Asian countries to avoid potential economic losses to the global koi industry.

1. -Lipoic acid (-LA) activates antioxidant pathways and exerts insulin-like actions via phosphatidylinositol 3-kinase (PI3K), and previous studies from the authors' laboratory support the essential role of PI3K-dependent CCAAT/enhancer binding protein (C/EBP) activation in antioxidant defence responses. 2. The study investigated whether -LA treatment promoted phase II antioxidant gene induction through C/EBP activation and, if so, whether combined treatment of -LA and insulin synergistically increased target gene expression. 3. -LA treatment induced GSTA2 in H4IIE cells in a concentration-and time-dependent manner. In cells transfected with the regulatory region of the GSTA2 gene, -LA treatment increased luciferase reporter-gene activity. Immunoblot, immunocytochemistry, and gel shift assays identified the nuclear translocation and DNA binding of C/EBP and C/EBP, but not C/EBP, in -LA-treated cells.Deletion of the C/EBP binding site abolished the ability of -LA to promote the luciferase gene activity. 4. -LA, when combined with low concentrations of insulin, transactivated the GSTA2 gene to a greater extent compared with -LA or a higher concentration of insulin treatment alone. Combined treatment of -LA with insulin not only potentiated insulin signalling, but also enhanced PI3K-dependent activation of C/EBP and C/EBP forms. -LA in combination with insulin substantially increased haemoxygenase-1, microsomal epoxide hydrolase and -nicotinamide adenine dinucleotide phosphate (NADPH) quinone oxidoreductase expression, verifying the enhanced induction of other phase II enzymes. A dominant negative C/EBP transfection experiment indicated that GSTA2 gene induction by simultaneous treatment of -LA and insulin was also dependent on C/EBPs. 5. The results demonstrate that -LA induces phase II enzymes via PI3K-dependent C/EBP and C/EBP activation, and enhances the ability of insulin to promote target gene induction.