MiR-125a-5p functions as a tumour suppressor in breast cancer by downregulating BAP1

J Cell Biochem. 2018 Nov;119(11):8773-8783. doi: 10.1002/jcb.27124. Epub 2018 Aug 4.

Abstract

MicroRNAs (miRNAs) play an important role in the regulation of human cancers, including breast cancer (BC). In the current study, we examined the expression pattern of the miRNA miR-125a-5p in human BC tissues, tumorigenesis of BC progression. We found that miR-125a-5p was significantly downregulated in human BC tissues. Overexpression of miR-125a-5p in a xenograft mouse model indicated that miR-125a-5p may function as a tumour suppressor during carcinogenesis. To explore the molecular mechanism by which miR-125a-5p contributes to BC progression, we predicted the target genes of miR-125a-5p and identified BC susceptibility gene 1-associated protein 1 (BAP1) as a direct target. Finally, we demonstrated that BAP1 had opposing effects to those of miR-125a-5p on BC cells, suggesting that miR-125a-5p may inhibit cell proliferation and promote cell apoptosis by negatively regulating BAP1. Taken together, our findings provide the first clues regarding the role of miR-125a-5p as a tumour suppressor in BC via the inhibition of BAP1 translation.

Keywords: BAP1; breast cancer; miR-125a-5p.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis
  • Breast Neoplasms / genetics*
  • Breast Neoplasms / metabolism
  • Carcinogenesis / genetics
  • Carcinogenesis / metabolism
  • Cell Proliferation
  • Cell Survival
  • Down-Regulation*
  • Female
  • Gene Silencing
  • Genes, Tumor Suppressor*
  • Humans
  • MCF-7 Cells
  • Mice
  • Mice, Nude
  • MicroRNAs / chemistry
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Molecular Mimicry
  • Molecular Targeted Therapy
  • Transfection
  • Tumor Burden
  • Tumor Suppressor Proteins / genetics*
  • Tumor Suppressor Proteins / metabolism
  • Ubiquitin Thiolesterase / genetics*
  • Ubiquitin Thiolesterase / metabolism
  • Xenograft Model Antitumor Assays

Substances

  • BAP1 protein, human
  • MIRN125 microRNA, human
  • MicroRNAs
  • Tumor Suppressor Proteins
  • Ubiquitin Thiolesterase