miRNA-205 affects infiltration and metastasis of breast cancer

Biochem Biophys Res Commun. 2013 Nov 8;441(1):139-43. doi: 10.1016/j.bbrc.2013.10.025. Epub 2013 Oct 12.

Abstract

Background: An increasing number of studies have shown that miRNAs are commonly deregulated in human malignancies, but little is known about the function of miRNA-205 (miR-205) in human breast cancer. The present study investigated the influence of miR-205 on breast cancer malignancy.

Methods: The expression level of miR-205 in the MCF7 breast cancer cell line was determined by quantitative (q)RT-PCR. We then analyzed the expression of miR-205 in breast cancer and paired non-tumor tissues. Finally, the roles of miR-205 in regulating tumor proliferation, apoptosis, migration, and target gene expression were studied by MTT assay, flow cytometry, qRT-PCR, Western blotting and luciferase assay.

Results: miR-205 was downregulated in breast cancer cells or tissues compared with normal breast cell lines or non-tumor tissues. Overexpression of miR-205 reduced the growth and colony-formation capacity of MCF7 cells by inducing apoptosis. Overexpression of miR-205 inhibited MCF7 cell migration and invasiveness. By bioinformation analysis, miR-205 was predicted to bind to the 3' untranslated regions of human epidermal growth factor receptor (HER)3 mRNA, and upregulation of miR-205 reduced HER3 protein expression.

Conclusion: miR-205 is a tumor suppressor in human breast cancer by post-transcriptional inhibition of HER3 expression.

Keywords: Breast cancer; Tumor suppressor; miRNA-205; miRNAs.

MeSH terms

  • Apoptosis / genetics
  • Breast Neoplasms / genetics*
  • Breast Neoplasms / pathology*
  • Cell Proliferation
  • Down-Regulation / genetics
  • Female
  • Gene Expression Regulation, Neoplastic
  • Humans
  • MCF-7 Cells
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Neoplasm Invasiveness
  • Neoplasm Metastasis
  • Receptor, ErbB-3 / metabolism
  • Tumor Stem Cell Assay

Substances

  • MIRN205 microRNA, human
  • MicroRNAs
  • ERBB3 protein, human
  • Receptor, ErbB-3