title: [Effects of chloroquine in reversing multidrug resistance in HNE1/DDP cell line].
abstract: OBJECTIVE
  To investigate the effect of chloroquine in reversing multidrug resistance (MDR) of HNE1/DDP cell line and explore the mechanism.
  
  
  METHODS
  MTT assay was used to detect the cell viability of HNE1 and HNE1/DDP after exposure to different concentrations of DDP (2, 4, 8, 16 and 32 µmol/L) and different concentrations of chloroquine (5, 10, 20, 40, and 80 µmol/L). q-PCR was used to assess the expression of MDR1 mRNA and Western blotting was employed to detect P-glycoprotein (P-gp) expression in HNE1 and HNE1/DDP cells exposed to 5 and 10 µmol/L chloroquine. The cell apoptosis rate of HNE1 and HNE1/DDP cells exposed to 10 and 20 µmol<L chloroquine was determined by PI assay.
  
  
  RESULTS
  Chloroquine exposure caused dose-dependent suppression of the proliferation in both HNE1 and HNE1<DDP cells, and significantly reversed multidrug resistance in HNE1<DDP cells. The expressions of MDR1 mRNA and P-gp protein were significantly lowered in the cells treated with chloroquine.
  
  
  CONCLUSIONS
  Chloroquine can reverse multidrug resistance in HNE1<DDP cells possibly through down-regulation of MDR1 and inhibition of P-gp protein.
authors.affiliation: Department of Basic Medical Sciences, Bengbu Medical College, Bengbu 233030, China.E-mail: zhxww@foxmail.com.
authors.forename: Haoxuan
authors.initials: H
authors.lastname: Zhang
authors.forename: Xiaojin
authors.initials: X
authors.lastname: Sun
authors.forename: Yiming
authors.initials: Y
authors.lastname: Sun
authors.forename: Surong
authors.initials: S
authors.lastname: Zhao
authors.forename: Chenchen
authors.initials: C
authors.lastname: Jiang
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis; D045744:Cell Line, Tumor; D002738:Chloroquine / Q000494:pharmacology*; D015536:Down-Regulation; D018432:Drug Resistance, Multiple / Q000187:drug effects*; D019008:Drug Resistance, Neoplasm / Q000187:drug effects*; D006801:Humans
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D002738:Chloroquine