title: Multidrug resistance gene (MDR-1) expression as a useful prognostic factor in patients with human hepatocellular carcinoma after surgical resection.
abstract: BACKGROUND
  Multidrug resistance gene (MDR-1) overexpression has been correlated with tumor aggressiveness and worse prognosis in some human neoplasms. The aim of this study is to evaluate the clinical value of MDR-1 mRNA expression as a prognostic factor after surgical resection in human hepatocellular carcinoma (HCC).
  
  
  METHODS
  MDR-1 mRNA levels in tissue samples from 34 patients with HCC, who underwent surgical resection, were measured by quantitative northern blot analysis. We stratified these patients into two groups according to a ratio of MDR-1 mRNA levels of HCC to nontumorous tissue; MDR-1 mRNA ratio > or = 1.0 and < 1.0. The overall and disease-free survival rates were analyzed using multivariate regression analysis.
  
  
  RESULTS
  The median survival periods were 10.3 and 35.8 months for patients with the MDR-1 mRNA ratio > or = 1.0 and < 1.0, respectively, and the corresponding 5-year survival rates were 33 and 54%, respectively, P < 0.05. The multivariate analysis revealed that TNM stage and MDR-1 mRNA ratio were independent factors for predicting overall survival after surgical resection.
  
  
  CONCLUSIONS
  This study suggested that the measurement of the MDR-1 mRNA levels in HCC and nontumorous liver tissue might be a useful prognostic factor after surgical resection in patients with HCC.
authors.affiliation: First Department of Surgery, School of Medicine, Chiba University, Chuo-Ku, Chiba, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Kato
authors.forename: M
authors.initials: M
authors.lastname: Miyazaki
authors.forename: S
authors.initials: S
authors.lastname: Ambiru
authors.forename: H
authors.initials: H
authors.lastname: Yoshitomi
authors.forename: H
authors.initials: H
authors.lastname: Ito
authors.forename: K
authors.initials: K
authors.lastname: Nakagawa
authors.forename: H
authors.initials: H
authors.lastname: Shimizu
authors.forename: O
authors.initials: O
authors.lastname: Yokosuka
authors.forename: N
authors.initials: N
authors.lastname: Nakajima
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000096:biosynthesis* / Q000235:genetics; D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000235:genetics* / Q000601:surgery; D018572:Disease-Free Survival; D005260:Female; D019450:Genes, MDR; D006801:Humans; D008113:Liver Neoplasms / Q000235:genetics* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D012333:RNA, Messenger / Q000032:analysis; D016019:Survival Analysis
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D012333:RNA, Messenger