MicroRNAs regulate CYP3A4 expression via direct and indirect targeting

Drug Metab Dispos. 2009 Oct;37(10):2112-7. doi: 10.1124/dmd.109.027680. Epub 2009 Jul 6.


CYP3A4 metabolizes many drugs on the market. Although transcriptional regulation of CYP3A4 is known to be tightly controlled by some nuclear receptors (NR) including vitamin D receptor (VDR/NR1I1), posttranscriptional regulation of CYP3A4 remains elusive. In this study, we show that noncoding microRNAs (miRNAs) may control posttranscriptional and transcriptional regulation of CYP3A4 by directly targeting the 3'-untranslated region (3'UTR) of CYP3A4 and indirectly targeting the 3'UTR of VDR, respectively. Luciferase reporter assays showed that CYP3A4 3'UTR-luciferase activity was significantly decreased in human embryonic kidney 293 cells transfected with plasmid that expressed microRNA-27b (miR-27b) or mouse microRNA-298 (mmu-miR-298), whereas the activity was unchanged in cells transfected with plasmid that expressed microRNA-122a or microRNA-328. Disruption of the corresponding miRNA response element (MRE) within CYP3A4 3'UTR led to a 2- to 3-fold increase in luciferase activity. Immunoblot analyses indicated that CYP3A4 protein was down-regulated over 30% by miR-27b and mmu-miR-298 in LS-180 and PANC1 cells. The decrease in CYP3A4 protein expression was associated with significantly decreased CYP3A4 mRNA levels, as determined by quantitative real-time PCR (qPCR) analyses. Likewise, interactions of miR-27b or mmu-miR-298 with VDR 3'UTR were supported by luciferase reporter assays. The mmu-miR-298 MRE site is well conserved within the 3'UTR of mouse, rat, and human VDR. Down-regulation of VDR by the two miRNAs was supported by immunoblot and qPCR analyses. Furthermore, overexpression of miR-27b or mmu-miR-298 in PANC1 cells led to a lower sensitivity to cyclophosphamide. Together, these findings suggest that CYP3A4 gene expression may be regulated by miRNAs at both the transcriptional and posttranscriptional level.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cytochrome P-450 CYP3A / genetics
  • Cytochrome P-450 CYP3A / metabolism*
  • Gene Expression Regulation / drug effects*
  • Gene Expression Regulation / physiology
  • Gene Targeting / methods*
  • Humans
  • Male
  • Mice
  • MicroRNAs / genetics
  • MicroRNAs / pharmacology*
  • MicroRNAs / physiology
  • RNA, Messenger / metabolism
  • RNA, Messenger / pharmacology
  • Tumor Cells, Cultured


  • MicroRNAs
  • RNA, Messenger
  • Cytochrome P-450 CYP3A
  • CYP3A4 protein, human