title: Caco-2 cells - expression, regulation and function of drug transporters compared with human jejunal tissue.
abstract: BACKGROUND
  Induction or inhibition of drug transporting proteins by concomitantly administered drugs can cause serious drug-drug interactions (DDIs). However, in vitro assays currently available are mostly for studying the inhibitory potential of drugs on intestinal transporter proteins, rather than induction. Therefore, this study investigated the suitability of the frequently used intestinal Caco-2 cell line to predict transporter-mediated DDIs as caused by induction via activation of nuclear receptors.
  
  
  METHODS
  TaqMan® low density arrays and LC-MS/MS based targeted proteomics were used to evaluate transporter expression in Caco-2 cells in comparison with jejunal tissue, in culture-time dependence studies and after incubation with different known inducers of drug metabolism and transport. Additionally, studies on ABCB1 function were performed using Transwell® assays with [3H]-digoxin and [3H]-talinolol as substrates after incubation with the prototypical inducers rifampicin, St John's wort, carbamazepine and efavirenz.
  
  
  RESULTS
  The gene and protein expression pattern of drug transporters in Caco-2 cells and jejunal tissue differed considerably. For some transporters culture-time dependent differences in mRNA expression and/or protein abundance could be determined. Finally, none of the studied prototypical inducers showed an effect either on mRNA expression and protein abundance or on the function of ABCB1.
  
  
  CONCLUSIONS
  Differences in transporter expression in Caco-2 cells compared with jejunal tissue, as well as expression dependence on culture time must be considered in in vitro studies to avoid under- or overestimation of certain transporters. The Caco-2 cell model is not suitable for the evaluation of DDIs caused by transporter induction. Copyright © 2016 John Wiley & Sons, Ltd.
authors: Department of Clinical Pharmacology, Center of Drug Absorption and Transport, University Medicine, Greifswald, Germany.
authors: S
authors: S
authors: Brück
authors: Department of Clinical Pharmacology, Center of Drug Absorption and Transport, University Medicine, Greifswald, Germany.
authors: J
authors: J
authors: Strohmeier
authors: Department of Clinical Pharmacology, Center of Drug Absorption and Transport, University Medicine, Greifswald, Germany.
authors: D
authors: D
authors: Busch
authors: Department of Experimental and Clinical Pharmacology, Pomeranian Medical University, Szczecin, Poland.
authors: M
authors: M
authors: Drozdzik
authors: Department of Clinical Pharmacology, Center of Drug Absorption and Transport, University Medicine, Greifswald, Germany.
authors: S
authors: S
authors: Oswald
mesh_terms: D018435:ATP Binding Cassette Transporter, Subfamily B / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D000328:Adult; D001692:Biological Transport; D018938:Caco-2 Cells; D002853:Chromatography, Liquid; D003106:Colon / Q000187:drug effects / Q000378:metabolism*; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism*; D007583:Jejunum / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D049990:Membrane Transport Modulators / Q000494:pharmacology; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D004364:Pharmaceutical Preparations / Q000378:metabolism*; D010641:Phenotype; D016133:Polymerase Chain Reaction; D040901:Proteomics / Q000379:methods; D053719:Tandem Mass Spectrometry; D055815:Young Adult
chemical_list: C513055:ABCB1 protein, human; D018435:ATP Binding Cassette Transporter, Subfamily B; D049990:Membrane Transport Modulators; D026901:Membrane Transport Proteins; D004364:Pharmaceutical Preparations
keywords: Caco-2 cell model; drug transporters; jejunal tissue