MiR-26a inhibits proliferation and migration of breast cancer through repression of MCL-1

PLoS One. 2013 Jun 4;8(6):e65138. doi: 10.1371/journal.pone.0065138. Print 2013.


Breast cancer is the most commonly malignancies in women. MicroRNAs are a family of small non-coding RNAs 18-25 nucleotides in length that post-transcriptionally modulate gene expression. MiR-26a has been reported as a tumor suppressor microRNA in breast cancer, which is attributed mainly to targeting of MTDH and EZH2, however, the expression profile and therapeutic potential of miR-26a is still unclear. Here we demonstrate that miR-26a is down-regulated in breast cancer cells and clinical specimens and its modulation in breast cancer cells regulates cell proliferation, colony formation, migration and apoptosis. MCL-1, an anti-apoptotic member of the Bcl-2 family, as novel targets of miR-26a was found to be in reverse correlation with ectopic expression of miR-26a and knockdown of MCL-1 phenocopied the effect of miR-26a in breast cancer cell lines. It was further explored that miR-26a increased sensitivity of breast cancer cells to paclitaxel in which MCL-1 was involved. Thus, miR-26a impacts on cell proliferation and migration of breast cancer by regulating several carcinogenesis-related processes, including a novel mechanism involving the targeting of MCL-1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Animals
  • Apoptosis / drug effects
  • Apoptosis / genetics
  • Base Sequence
  • Breast Neoplasms / genetics*
  • Breast Neoplasms / pathology*
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • Cell Movement / genetics*
  • Cell Proliferation / drug effects
  • Cell Survival / drug effects
  • Cell Survival / genetics
  • Down-Regulation / drug effects
  • Down-Regulation / genetics*
  • Female
  • Humans
  • MicroRNAs / genetics*
  • Middle Aged
  • Myeloid Cell Leukemia Sequence 1 Protein / genetics*
  • Paclitaxel / pharmacology


  • MCL1 protein, human
  • MIRN26A microRNA, human
  • MicroRNAs
  • Myeloid Cell Leukemia Sequence 1 Protein
  • Paclitaxel

Grant support

This work was supported by funds from Key Program of National Natural Science Foundation of China number 31030061, National Natural Science Foundation of China number 81272514, National Natural Science Foundation of China (31100935), and the China Postdoctoral Science Foundation (2012M520075). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.