MicroRNA hsa-miR-25-3p suppresses the expression and drug induction of CYP2B6 in human hepatocytes

Biochem Pharmacol. 2016 Aug 1;113:88-96. doi: 10.1016/j.bcp.2016.06.007. Epub 2016 Jun 14.

Abstract

Cytochrome P450 2B6 (CYP2B6), mainly expressed in the liver and brain, is important for processing a number of widely used drugs. Variations in CYP2B6 expression are associated with decreased drug efficacy or adverse effects in some patients. Although CYP2B6 genetic variants are associated with its differential expression, epigenetic mechanisms affecting CYP2B6 gene regulation have not been established. Sequence analysis identified 29 domains in the CYP2B6 mRNA transcript that could be subject to regulation by microRNAs. Inverse correlations were found in human hepatocytes for the levels of the microRNAs hsa-miR-504-5p and hsa-miR-25-3p compared with CYP2B6 mRNA. Reporter gene assays showed that hsa-miR-25-3p suppresses CYP2B6 expression by targeting a specific sequence in the 3'-untranslated region of the mRNA transcript. Electrophoretic mobility shift assays confirmed that hsa-miR-25-3p forms stable complexes with its cognate mRNA sequence and that it recruits cellular factors, including Ago-4. Transfection of HepaRG cells with hsa-miR-25-3p mimics inhibited expression of the endogenous CYP2B6 gene and it also decreased rifampicin-dependent induction of CYP2B6 at the mRNA and protein levels. In summary, in silico and in vitro analyses show that hsa-miR-25-3p suppresses CYP2B6 expression in human liver cells via an epigenetic mechanism.

Keywords: CYP2B6; Drug metabolizing enzymes; Inter-individual variability; Pharmacogenomics; hsa-miR-25-3p.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Binding Sites
  • Cell Culture Techniques
  • Cell Line, Tumor
  • Cytochrome P-450 CYP2B6 / genetics*
  • Cytochrome P-450 CYP2B6 / metabolism*
  • Cytochrome P-450 CYP2B6 Inhibitors / pharmacology
  • Electrophoretic Mobility Shift Assay
  • Epigenesis, Genetic*
  • Gene Expression Regulation, Enzymologic* / drug effects
  • Hepatocytes / drug effects
  • Hepatocytes / metabolism*
  • Humans
  • Liver / metabolism
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rifampin / pharmacology

Substances

  • Cytochrome P-450 CYP2B6 Inhibitors
  • MIRN25 microRNA, human
  • MicroRNAs
  • RNA, Messenger
  • CYP2B6 protein, human
  • Cytochrome P-450 CYP2B6
  • Rifampin