title: Nogo-C contributes to HCC tumorigenesis via suppressing cell growth and its interactome analysis with comparative proteomics research.
abstract: OBJECTIVE
  Neurite outgrowth inhibitor proteins (Nogos) comprise a family of three major members and are characterized by a conserved RHD domain. Among all the members, Nogo-B was identified to be significantly elevated and to play an important role in liver cirrhosis while Nogo-C was the shortest one and received little attention. The aim of this study is to investigate the relevance and mechanism of Nogo-C involved in Hepatocellular carcinoma (HCC).
  
  
  METHODS
  The expression of Nogo-C in paired HCC specimens was measured with quantitative RT-PCR. The function of Nogo-C over expressing in SMMC-7721 and WRL-68 HCC cell lines were estimated through cell proliferation assay and colony formation assay. A proteome-wide identification of Nogo-C-binding proteins was performed using affinity purification combined with a highly sensitive mass spectrometric technique. The protein interactions were confirmed using co-IP and immunofluorescence confocal assays.
  
  
  RESULTS
  Compared with the neighboring pathologically normal tissues, the expression of Nogo-C mRNA was extremely down-regulated in HCC specimens and was significantly related to greater tumor size and worse prognosis. Overexpression of Nogo-C in HCC cell lines resulted in an inhibition of cell growth. A total of 73 proteins were detected and considered in association with Nogo-C, among which B-raf and Nogo-B were validated.
  
  
  CONCLUSIONS
  We identify Nogo-C as a tumor suppressor gene in HCC and B-raf as a novel interacting protein. These findings provide new directions for the mechanism research of Nogo family.
authors: State Key Laboratory of Genetic Engineering, Fudan University Shanghai, China ; National Engineering Center for Biochip at Shanghai Shanghai, China.
authors: Xing
authors: X
authors: Liu
authors: College of Bioscience and Biotechnology, Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, Yangzhou University Yangzhou, China.
authors: Shu-Jian
authors: SJ
authors: Cui
authors: Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University Suzhou, China.
authors: Shi-Jun
authors: SJ
authors: Zhu
authors: Department of Orthopaedic Surgery, The First Affiliated Hospital of Soochow University Suzhou, China.
authors: De-Chun
authors: DC
authors: Geng
authors: State Key Laboratory of Genetic Engineering, Fudan University Shanghai, China.
authors: Long
authors: L
authors: Yu
mesh_terms: D000595:Amino Acid Sequence; D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002846:Chromatography, Affinity; D056148:Chromatography, Reverse-Phase; D015536:Down-Regulation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D047468:Immunoprecipitation; D008113:Liver Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D008969:Molecular Sequence Data; D009185:Myelin Proteins / Q000235:genetics / Q000378:metabolism*; D000070798:Nogo Proteins; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D060066:Protein Interaction Maps; D040901:Proteomics / Q000379:methods; D048493:Proto-Oncogene Proteins B-raf / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D015398:Signal Transduction; D053719:Tandem Mass Spectrometry; D013997:Time Factors; D014162:Transfection; D047368:Tumor Burden
chemical_list: D009185:Myelin Proteins; D000070798:Nogo Proteins; D012333:RNA, Messenger; C000603199:RTN4 protein, human; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf
keywords: B-raf; HCC; Nogo-C; comparative proteomics; interactome; tumor suppressor gene