Let-7a inhibits proliferation and induces apoptosis by targeting EZH2 in nasopharyngeal carcinoma cells

Oncol Rep. 2012 Dec;28(6):2101-6. doi: 10.3892/or.2012.2027. Epub 2012 Sep 12.

Abstract

Let-7a is frequently downregulated in various types of human cancer including nasopharyngeal carcinoma. However, the underlying mechanism of let-7a action in nasopharyngeal carcinoma remains elusive. In this study, we show that the enhancer of zeste homolog 2 (EZH2) is a direct target of let-7a in human nasopharyngeal carcinoma cells. The inhibition of EZH2 in vitro by let-7a, EZH2 siRNA, attenuated nasopharyngeal carcinoma cell growth, inhibited cell proliferation and induced cell apoptosis. In addition, for each biological process we identified ontology-associated transcripts that significantly correlate with EZH2 expression. Finally, the expression of EZH2 significantly abrogated let-7a-mediated cell proliferation and apoptosis in the nasopharyngeal carcinoma cells. Taken together, our results suggest that let-7a and EZH2 may be potential therapeutic targets for nasopharyngeal carcinoma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis
  • Carcinoma
  • Cell Proliferation
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Enhancer of Zeste Homolog 2 Protein
  • Gene Expression Regulation, Neoplastic
  • Humans
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Nasopharyngeal Carcinoma
  • Nasopharyngeal Neoplasms / metabolism*
  • Nasopharyngeal Neoplasms / pathology
  • Polycomb Repressive Complex 2 / genetics*
  • Polycomb Repressive Complex 2 / metabolism*
  • RNA Interference
  • RNA, Small Interfering
  • Tumor Cells, Cultured

Substances

  • DNA-Binding Proteins
  • MicroRNAs
  • RNA, Small Interfering
  • mirnlet7 microRNA, human
  • EZH2 protein, human
  • Enhancer of Zeste Homolog 2 Protein
  • Polycomb Repressive Complex 2