title: Liver-specific expressions of HBx and src in the p53 mutant trigger hepatocarcinogenesis in zebrafish.
abstract: Hepatocarcinogenesis is a multistep process that starts from fatty liver and transitions to fibrosis and, finally, into cancer. Many etiological factors, including hepatitis B virus X antigen (HBx) and p53 mutations, have been implicated in hepatocarcinogenesis. However, potential synergistic effects between these two factors and the underlying mechanisms by which they promote hepatocarcinogenesis are still unclear. In this report, we show that the synergistic action of HBx and p53 mutation triggers progressive hepatocellular carcinoma (HCC) formation via src activation in zebrafish. Liver-specific expression of HBx in wild-type zebrafish caused steatosis, fibrosis and glycogen accumulation. However, the induction of tumorigenesis by HBx was only observed in p53 mutant fish and occurred in association with the up-regulation and activation of the src tyrosine kinase pathway. Furthermore, the overexpression of src in p53 mutant zebrafish also caused hyperplasia, HCC, and sarcomatoid HCC, which were accompanied by increased levels of the signaling proteins p-erk, p-akt, myc, jnk1 and vegf. Increased expression levels of lipogenic factors and the genes involved in lipid metabolism and glycogen storage were detected during the early stages of hepatocarcinogenesis in the HBx and src transgenic zebrafish. The up-regulation of genes involved in cell cycle regulation, tumor progression and other molecular hallmarks of human liver cancer were found at later stages in both HBx and src transgenic, p53 mutant zebrafish. Together, our study demonstrates that HBx and src overexpression induced hepatocarcinogenesis in p53 mutant zebrafish. This phenomenon mimics human HCC formation and provides potential in vivo platforms for drug screening for therapies for human liver cancer.
authors.affiliation: Institute of Molecular and Genomic Medicine, National Health Research Institutes, Zhunan, Miaoli, Taiwan ; Department of Life Sciences, National Central University, Jhongli City, Taoyuan, Taiwan.
authors.forename: Jeng-Wei
authors.initials: JW
authors.lastname: Lu
authors.forename: Wan-Yu
authors.initials: WY
authors.lastname: Yang
authors.forename: Su-Mei
authors.initials: SM
authors.lastname: Tsai
authors.forename: Yueh-Min
authors.initials: YM
authors.lastname: Lin
authors.forename: Pen-Heng
authors.initials: PH
authors.lastname: Chang
authors.forename: Jim-Ray
authors.initials: JR
authors.lastname: Chen
authors.forename: Horng-Dar
authors.initials: HD
authors.lastname: Wang
authors.forename: Jen-Leih
authors.initials: JL
authors.lastname: Wu
authors.forename: Shiow-Lian Catherine
authors.initials: SL
authors.lastname: Jin
authors.forename: Chiou-Hwa
authors.initials: CH
authors.lastname: Yuh
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D017209:Apoptosis / Q000235:genetics; D014408:Biomarkers, Tumor / Q000378:metabolism; D000081247:CSK Tyrosine-Protein Kinase; D063646:Carcinogenesis / Q000235:genetics*; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D002453:Cell Cycle / Q000235:genetics; D004789:Enzyme Activation / Q000235:genetics; D005355:Fibrosis; D015870:Gene Expression; D006003:Glycogen / Q000378:metabolism; D006801:Humans; D006965:Hyperplasia / Q000235:genetics; D050155:Lipogenesis / Q000235:genetics; D008099:Liver / Q000378:metabolism* / Q000473:pathology; D008113:Liver Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology*; D009154:Mutation; D009362:Neoplasm Metastasis; D009928:Organ Specificity; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics; D015398:Signal Transduction / Q000235:genetics; D015534:Trans-Activators / Q000235:genetics*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*; D054334:Viral Regulatory and Accessory Proteins; D015027:Zebrafish / Q000235:genetics / Q000378:metabolism; D019061:src-Family Kinases / Q000235:genetics*
chemical_list: D014408:Biomarkers, Tumor; D018809:Proliferating Cell Nuclear Antigen; D011993:Recombinant Fusion Proteins; D015534:Trans-Activators; D016159:Tumor Suppressor Protein p53; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein; D006003:Glycogen; D000081247:CSK Tyrosine-Protein Kinase; D019061:src-Family Kinases; C000631346:CSK protein, human