A fluorescent cell-based assay for cytochrome P-450 isozyme 1A2 induction and inhibition

J Biomol Screen. 2000 Aug;5(4):249-54. doi: 10.1177/108705710000500407.


High throughput lead optimization requires simple, homogeneous cell-based assays capable of defining the druglike properties of first-round screening hits. Induction and inhibition of the Phase I drug-metabolizing enzymes are central to this process. We report here an assay for induction and inhibition of cytochrome P-450 (CYP) isozyme 1A2 that meets these requirements. It utilizes HepG2/C3A, a human liver cell line, and ethoxyresorufin. Using methylcholanthrene, CYP1A2 can be induced dramatically, and it is inhibited by furafylline, a mechanism-based inhibitor of this enzyme.

Publication types

  • Evaluation Study

MeSH terms

  • Cell Line
  • Cytochrome P-450 CYP1A2 / analysis*
  • Cytochrome P-450 CYP1A2 / biosynthesis
  • Cytochrome P-450 CYP1A2 Inhibitors
  • Drug Evaluation, Preclinical / methods
  • Enzyme Induction / drug effects
  • Enzyme Inhibitors / pharmacology
  • Fluorescence
  • Humans
  • Methylcholanthrene / pharmacology
  • Oxazines
  • Theophylline / analogs & derivatives
  • Theophylline / pharmacology


  • Cytochrome P-450 CYP1A2 Inhibitors
  • Enzyme Inhibitors
  • Oxazines
  • Methylcholanthrene
  • ethoxyresorufin
  • Theophylline
  • furafylline
  • Cytochrome P-450 CYP1A2