title: Differential expression of Rab27A/B correlates with clinical outcome in hepatocellular carcinoma.
abstract: OBJECTIVE
  To investigate the association of Rab27A and Rab27B expression with clinicopathological characteristics and prognosis of hepatocellular carcinoma (HCC).
  
  
  METHODS
  We used reverse transcription polymerase chain reaction (RT-PCR), real-time PCR, and Western blotting to detect Rab27A and Rab27B mRNA and protein expression in 5 human HCC lines and the immortalized hepatic HL-7702 cell line. We further examined 148 primary HCC samples matched with adjacent normal tissue and 80 non-HCC specimens by immunohistochemistry to evaluate the correlation of Rab27A and Rab27B expression with clinicopathological features and prognosis.
  
  
  RESULTS
  Our data showed that Rab27A and Rab27B were differentially expressed in cell lines and primary HCC tumors. Rab27A mRNA and protein were detected in 67% (4/6) of human cell lines and 80% (4/5) of HCC cell lines, while Rab27B was found in 50% (3/6) of human lines and 40% (2/5) of HCC lines. Rab27A expression was higher in primary HCC (46.2%, 66/143) than in matched adjacent tissue (24.3%, 33/136, P < 0.001), whereas immunopositivity for Rab27B was lower in primary HCC (57.4%, 81/141) than in matched adjacent tissue (87.5%, 119/136, P < 0.001). Analysis of clinicopathological characteristics of 148 HCC specimens revealed significant correlations between Rab27A and Rab27B expression and tumor tumor-node-metastasis (TNM) classification (P = 0.046 and P = 0.027, respectively), and between strong Rab27A expression and tumor differentiation grade (P = 0.008). Survival analyses revealed that patients with Rab27A(+) or Rab27B(+) tumors had significantly reduced overall survival compared with that of patients with Rab27A(-) or Rab27B(-) tumors (P = 0.015 and P = 0.005, respectively). Risk analyses revealed that Rab27B(+) and TNM III-IV were independent poor prognosis factors associated with a 3.36- and 3.37-fold higher relative risk of death, respectively.
  
  
  CONCLUSIONS
  Rab27A and Rab27B expression were closely correlated with tumor progression and can be valuable prognostic indicators for HCC patients.
authors.affiliation: Department of Oncology, the First Affiliated Hospital, the General Hospital of Chinese People's Liberation Army, Beijing 100048, China.
authors.forename: Wei-Wei
authors.initials: WW
authors.lastname: Dong
authors.forename: Quan
authors.initials: Q
authors.lastname: Mou
authors.forename: Jian
authors.initials: J
authors.lastname: Chen
authors.forename: Jian-Tao
authors.initials: JT
authors.lastname: Cui
authors.forename: Wen-Mei
authors.initials: WM
authors.lastname: Li
authors.forename: Wen-Hua
authors.initials: WH
authors.lastname: Xiao
mesh_terms: D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000737:chemistry* / Q000401:mortality / Q000473:pathology; D045744:Cell Line, Tumor; D018450:Disease Progression; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008113:Liver Neoplasms / Q000737:chemistry* / Q000401:mortality / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D020691:rab GTP-Binding Proteins / Q000032:analysis* / Q000235:genetics / Q000502:physiology; D000075745:rab27 GTP-Binding Proteins
chemical_list: D000075745:rab27 GTP-Binding Proteins; C066694:RAB27A protein, human; C512960:Rab27B protein, human; D020691:rab GTP-Binding Proteins