title: Down-regulation of retinol binding protein 5 is associated with aggressive tumor features in hepatocellular carcinoma.
abstract: OBJECTIVE
  Acyclic retinoid (ACR) has been shown to be a promising chemopreventive agent for hepatocellular carcinoma (HCC) after curative resection. The effects of retinoid are mediated by retinol-binding proteins (RBPs) through regulating cell proliferation and differentiation.
  
  
  METHODS
  This study investigated the clinical significance of RBP5 in HCC. RBP5 mRNA level was examined by real-time quantitative PCR on 52 matched tumor and adjacent non-tumor liver tissues, and on ten normal livers. Expression of RBP5 protein was examined using Western blotting analysis and immunohistochemistry.
  
  
  RESULTS
  Down-regulation of RBP5 was found in HCC tissues at both mRNA and protein levels. Decreased RBP5 level was closely related to poor differentiation (P=0.02) and large tumor size (P=0.01). Low level of RPB5 was associated with poor overall survival (P=0.02), and was an independent prognostic factor for HCC.
  
  
  CONCLUSIONS
  Our study revealed that RBP5 down-regulation in HCC was associated with aggressive tumor features, suggesting an important role of RPB5 in HCC progression.
authors.affiliation: Department of Surgery, The University of Hong Kong, L9-55, Laboratory Block, Faculty of Medicine Building, 21 Sassoon Road Pokfulam, Hong Kong, China.
authors.forename: Jenny C Y
authors.initials: JC
authors.lastname: Ho
authors.forename: Siu Tim
authors.initials: ST
authors.lastname: Cheung
authors.forename: Wing Sem
authors.initials: WS
authors.lastname: Poon
authors.forename: Yuk Ting
authors.initials: YT
authors.lastname: Lee
authors.forename: Irene O L
authors.initials: IO
authors.lastname: Ng
authors.forename: Sheung Tat
authors.initials: ST
authors.lastname: Fan
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000235:genetics / Q000378:metabolism* / Q000401:mortality; D018450:Disease Progression; D015536:Down-Regulation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry; D008099:Liver; D008113:Liver Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000378:metabolism; D012177:Retinol-Binding Proteins / Q000378:metabolism*; D054840:Retinol-Binding Proteins, Cellular / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016019:Survival Analysis
chemical_list: C526967:RBP5 protein, human; D012333:RNA, Messenger; D012177:Retinol-Binding Proteins; D054840:Retinol-Binding Proteins, Cellular