MiR-503 inhibited cell proliferation of human breast cancer cells by suppressing CCND1 expression

Tumour Biol. 2015 Nov;36(11):8697-702. doi: 10.1007/s13277-015-3623-8. Epub 2015 Jun 6.


Breast cancer is one of the most common malignancies and a major cause of cancer-related mortality all over the world. A growing body of reports revealed that microRNAs play essential roles in the progression of cancers. Aberrant expression of miR-503 has been reported in several kinds of cancer. The aim of the current study was to elucidate the role of miR-503 in the pathogenesis of breast cancer. In the present study, our results suggested that miR-503 expression was markedly downregulated in breast cancer tissues and cells. Overexpression of miR-503 in breast cancer cell lines reduced cell proliferation through inducing G0/G1 cell cycle arrest by targeting CCND1. Together, our findings provide new knowledge regarding the role of miR-503 in the progression of breast cancer and indicate the role of miR-503 as a tumor suppressor microRNA (miRNA) in breast cancer.

Keywords: Breast cancer; CCND1; Cell cycle; Cell proliferation; miR-503.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Breast Neoplasms / genetics*
  • Breast Neoplasms / pathology
  • Cell Proliferation / genetics*
  • Cyclin D1 / biosynthesis*
  • Cyclin D1 / genetics
  • Female
  • G1 Phase Cell Cycle Checkpoints / genetics
  • Gene Expression Regulation, Neoplastic
  • Humans
  • MCF-7 Cells
  • MicroRNAs / biosynthesis*
  • MicroRNAs / genetics


  • CCND1 protein, human
  • MIRN503 microRNA, human
  • MicroRNAs
  • Cyclin D1