title: Investigation of Pokemon-regulated proteins in hepatocellular carcinoma using mass spectrometry-based multiplex quantitative proteomics.
abstract: Pokemon is a transcription regulator involved in embryonic development, cellular differentiation and oncogenesis. It is aberrantly overexpressed in multiple human cancers including Hepatocellular carcinoma (HCC) and is considered as a promising biomarker for HCC. In this work, the isobaric tags for relative and absolute quantitation (iTRAQ)-based quantitative proteomics strategy was used to investigate the proteomic profile associated with Pokemon in human HCC cell line QGY7703 and human hepatocyte line HL7702. Samples were labeled with four-plex iTRAQ reagents followed by two-dimensional liquid chromatography coupled with tandem mass spectrometry analysis. A total of 24 differentially expressed proteins were selected as significant. Nine proteins were potentially up-regulated by Pokemon while 15 proteins were potentially down-regulated and many proteins were previously identified as potential biomarkers for HCC. Gene ontology (GO) term enrichment revealed that the listed proteins were mainly involved in DNA metabolism and biosynthesis process. The changes of glucose-6-phosphate 1-dehydrogenase (G6PD, up-regulated) and ribonucleoside-diphosphate reductase large sub-unit (RIM1, down-regulated) were validated by Western blotting analysis and denoted as Pokemon's function of oncogenesis. We also found that Pokemon potentially repressed the expression of highly clustered proteins (MCM3, MCM5, MCM6, MCM7) which played key roles in promoting DNA replication. Altogether, our results may help better understand the role of Pokemon in HCC and promote the clinical applications.
authors.affiliation: Department of Chemistry, Tsinghua University, Beijing 100084, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Bi
authors.forename: Yibao
authors.initials: Y
authors.lastname: Jin
authors.forename: Xiang
authors.initials: X
authors.lastname: Gao
authors.forename: Feng
authors.initials: F
authors.lastname: Liu
authors.forename: Dan
authors.initials: D
authors.lastname: Gao
authors.forename: Yuyang
authors.initials: Y
authors.lastname: Jiang
authors.forename: Hongxia
authors.initials: H
authors.lastname: Liu
mesh_terms: D015153:Blotting, Western; D006528:Carcinoma, Hepatocellular / Q000737:chemistry*; D045744:Cell Line, Tumor; D004268:DNA-Binding Proteins / Q000737:chemistry*; D003627:Data Interpretation, Statistical; D019204:GTP-Binding Proteins / Q000096:biosynthesis / Q000235:genetics; D005954:Glucosephosphate Dehydrogenase / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D007202:Indicators and Reagents; D008113:Liver Neoplasms / Q000737:chemistry*; D013058:Mass Spectrometry; D010957:Plasmids / Q000235:genetics; D040901:Proteomics / Q000379:methods*; D034741:RNA, Small Interfering; D012262:Ribonucleoside Diphosphate Reductase / Q000096:biosynthesis / Q000235:genetics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014157:Transcription Factors / Q000737:chemistry*; D014158:Transcription, Genetic; D014162:Transfection; D009419:Nerve Tissue Proteins
chemical_list: D004268:DNA-Binding Proteins; D019204:GTP-Binding Proteins; D005954:Glucosephosphate Dehydrogenase; D007202:Indicators and Reagents; D034741:RNA, Small Interfering; D012262:Ribonucleoside Diphosphate Reductase; D014157:Transcription Factors; C485514:ZBTB7A protein, human; C491492:RIMS1 protein, human; D009419:Nerve Tissue Proteins