Effect of CpG island methylation on microRNA expression in the k-562 cell line

Biochem Genet. 2012 Feb;50(1-2):122-34. doi: 10.1007/s10528-011-9478-9. Epub 2011 Nov 17.

Abstract

To test the hypothesis that methylation of a CpG island is associated with regulation of microRNA expression, we investigated CpG islands in the upstream sequences of microRNA precursors (pre-miRNAs) through bioinformatic analysis and determined whether the CpG islands were methylated by methylation-specific PCR in the k-562 cell line. We used 5-azacytidine for DNA demethylation, and changes in microRNA expression were detected by microarray assay, RT-PCR, and real-time PCR after 5-azacytidine induction. We showed that the CpG islands in the upstream regions of 18 pre-miRNAs were methylated, including miR-663, miR-369, miR-615, and miR-410, and promoter activity was detected in the upstream region of pre-miR-663. We found that a decrease in methylation of a CpG island could up-regulate the expression of miR-663, suggesting that miR-663 could be regulated by DNA methylation. Expression levels of miR-369, miR-615, and miR-410 were not regulated by DNA methylation in this cell line.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Azacitidine / pharmacology
  • CpG Islands*
  • DNA Methylation* / drug effects
  • Gene Expression Regulation
  • Humans
  • K562 Cells
  • MicroRNAs / genetics*
  • Neoplasm Proteins
  • Promoter Regions, Genetic
  • RNA Precursors
  • Real-Time Polymerase Chain Reaction

Substances

  • MIRN369 microRNA, human
  • MIRN410 microRNA, human
  • MIRN615 microRNA, human
  • MIRN663 microRNA, human
  • MicroRNAs
  • Neoplasm Proteins
  • RNA Precursors
  • URGCP protein, human
  • Azacitidine