title: [Expressions of Bim and ERKs in multidrug-resistant hepatic carcinoma cells].
abstract: OBJECTIVE
  To investigate the expressions of extracellular signal-regulated kinase (ERK) and the BH3-only subgroup of Bcl-2 related proteins (Bim) in multidrug-resistant hepatocellular carcinoma (HCC) cells and their association with drug resistance in the cells.
  
  
  METHODS
  The multdrug-resistant HepG-2 cell line was established by treatment with gradually increasing doses of ADM. CCK-8 assay was used to determine the drug sensitivity of the cells, and the expressions of MRP-1, P-gp, ERK1, ERK2, ERK5, and Bim were detected with Western blot. Bim mRNA expression level was measured using quantitative real-time PCR.
  
  
  RESULTS
  The drug resistance indices to ADM, 5-FU and CDDP was 6.8, 4.10, and 4.5 in HepG-2/ADM cells, respectively. The drug-resistantcells showed marked up-regulation of MRP-1, P-gp, ERK1, ERK2 and ERK5 with down-regulated phosphorylated ERK2 protein expression but no significant changes in phosphorylated ERK1 protein expression to result in a decreased ratio of P-ERK1/2 and P-ERK1/2. Bim mRNA and protein expressions were both decreased in HepG-2/ADM cells.
  
  
  CONCLUSIONS
  ERK and Bim are related to multidrug resistance in HepG-2/ADM cells.
authors.affiliation: Department of Gastrointestinal Surgery, Zhongshan Hospital, Xiamen University, Xiamen 361004, China.E-mail: yanfeng@xmzsh.com.
authors.forename: Feng
authors.initials: F
authors.lastname: Yan
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Wang
authors.forename: Quanming
authors.initials: Q
authors.lastname: Ma
authors.forename: Sibo
authors.initials: S
authors.lastname: Yuan
authors.forename: Nan
authors.initials: N
authors.lastname: Jiang
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism; D006528:Carcinoma, Hepatocellular / Q000378:metabolism*; D015536:Down-Regulation; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D056945:Hep G2 Cells; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism*; D010766:Phosphorylation; D015854:Up-Regulation
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D048049:Extracellular Signal-Regulated MAP Kinases