Mixed function oxidase and UDP-glucuronyltransferase activities in the human Hep G2 hepatoma cell line

Biochem Pharmacol. 1988 Nov 1;37(21):4111-6. doi: 10.1016/0006-2952(88)90103-7.


In cultured human hepatoma cells phenolphthalein glucuronidation was increased 3-fold by 2 mM phenobarbitone (PB) in the culture medium but not by 25 microM benz(a)anthracene (BA), while 1-naphthol glucuronidation was not increased by either PB or BA. Ethoxyresorufin O-deethylation (EROD) was increased 15-fold by BA but not by PB, while the O-dealkylations of pentoxyresorufin (PROD) and benzyloxyresorufin (BROD) were increased by either PB or BA. The BROD activity increased by BA was sensitive to inhibition by alpha-naphthoflavone whereas that induced by PB was not. This suggests induction of different cytochrome P-450 isoenzymes. Control Hep G2 cells had similar glucuronide conjugation and cytochrome reductase activities to freshly isolated human adult hepatocytes, but had lower O-dealkylation and elevated microsomal epoxide hydrolase activities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carcinoma, Hepatocellular / enzymology*
  • Cytochrome P-450 CYP2B1
  • Epoxide Hydrolases / metabolism
  • Glucuronosyltransferase / metabolism*
  • Humans
  • Liver / enzymology
  • Liver Neoplasms
  • Mixed Function Oxygenases / metabolism*
  • Oxazines / metabolism
  • Oxidation-Reduction
  • Oxidoreductases / metabolism
  • Tumor Cells, Cultured


  • Oxazines
  • ethoxyresorufin
  • Mixed Function Oxygenases
  • Oxidoreductases
  • Cytochrome P-450 CYP2B1
  • Glucuronosyltransferase
  • Epoxide Hydrolases