Relationship between expression level of P-glycoprotein and daunorubicin transport in LLC-PK1 cells transfected with human MDR1 gene

Biochem Pharmacol. 1997 Mar 7;53(5):741-6. doi: 10.1016/s0006-2952(96)00810-6.

Abstract

P-Glycoprotein-mediated transcellular transport and intracellular accumulation of [3H]daunorubicin were examined in cell monolayers with different levels of P-glycoprotein. The porcine kidney epithelial cell line LLC-PK1 was transfected with MDR1 cDNA, and four sublines, LLC-GA5, LLC-GA5-VLB4, LLC-GA5-COL10, and LLC-GA5-COL150, were obtained by culturing the cells in the absence or in the presence of 4 ng/mL vinblastine, 10 ng/mL colchicine, and 150 ng/mL colchicine, respectively. Western blot analysis showed a large difference in P-glycoprotein expression within these sublines. The degree of drug resistance was dependent on the expression level of P-glycoprotein. The amount of the unidirectional transport of [3H]daunorubicin by P-glycoprotein corresponded to the expression level of P-glycoprotein, which was followed by the decrease in intracellular accumulation of the agent. The concentration of cyclosporin A required for the inhibition of P-glycoprotein-mediated transport of [3H]daunorubicin was higher in cells with a high expression of P-glycoprotein. These findings suggest that the transport of daunorubicin by P-glycoprotein and its inhibition by cyclosporin A correspond to the expression level of P-glycoprotein.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / genetics
  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / physiology*
  • Animals
  • Antibiotics, Antineoplastic / pharmacokinetics*
  • Biological Transport
  • Cyclosporine / pharmacokinetics
  • Cyclosporine / pharmacology
  • Daunorubicin / pharmacokinetics*
  • Dose-Response Relationship, Drug
  • Humans
  • LLC-PK1 Cells
  • Swine
  • Transfection

Substances

  • ATP Binding Cassette Transporter, Subfamily B, Member 1
  • Antibiotics, Antineoplastic
  • Cyclosporine
  • Daunorubicin