microRNA-21 is upregulated in malignant melanoma and influences apoptosis of melanocytic cells

Exp Dermatol. 2012 Jul;21(7):509-14. doi: 10.1111/j.1600-0625.2012.01510.x.


Overexpression of microRNA-21 (miR-21) has been observed in various cancer types, but little is known about the role of miR-21 in melanoma. In this study, we demonstrate that levels of miR-21 are significantly increased in primary melanoma tissues as compared to benign nevi and in human melanoma cell lines as compared to melanocytic cell preparations. We show that downregulation of miR-21 in melanoma cell lines with high endogenous miR-21 expression induced apoptosis, whereas proliferation was not significantly altered. Upregulation of miR-21 in melanocytes resulted in increased proliferation and decreased apoptosis. However, in the MEWO melanoma cells with low endogenous miR-21 expression, upregulation of miR-21 had no functional effects. These findings indicate a potential pathogenetic role of miR-21 upregulation in a subgroup of melanomas.

MeSH terms

  • Apoptosis
  • Cell Line, Tumor
  • Cell Proliferation
  • Disease-Free Survival
  • Down-Regulation
  • Humans
  • Kaplan-Meier Estimate
  • Melanocytes / cytology
  • Melanocytes / metabolism*
  • Melanoma / metabolism*
  • MicroRNAs / metabolism*
  • Nevus, Pigmented / metabolism*
  • Retrospective Studies
  • Statistics, Nonparametric
  • Up-Regulation*


  • MIRN21 microRNA, human
  • MicroRNAs