ALCAM is indirectly modulated by miR-125b in MCF7 cells

Tumour Biol. 2015 May;36(5):3511-20. doi: 10.1007/s13277-014-2987-5. Epub 2014 Dec 25.

Abstract

MicroRNA (miRNA) deregulation is associated with various cancers. Among an expanding list of cancer-related miRNAs, deregulation of miR-125b has been well documented in many cancers including breast. Based on current knowledge, miR-125b is considered to be a tumor suppressor in breast cancers. While important messenger RNA (mRNA) targets have been defined for miR-125b, here, we aimed to further investigate direct/indirect consequences of miR-125b expression in breast cancer cells by using a transcriptome approach. Upon miR-125b expression, a total of 138 cancer-related genes were found to be differentially expressed in breast cancer cells. While only a few of these were predicted to be direct mRNA targets, majority of the gene expression changes were potentially downstream and indirect effects of miR-125b expression. Among these, activated leukocyte antigen molecule (ALCAM) mRNA and protein levels were found to be highly significantly increased upon miR-125b expression. Given the tumor suppressor role of miR-125b in our model system, upon silencing of ALCAM expression, cell proliferation rate re-increased in miR-125b-expressing cells. While ALCAM's possible context-dependent roles are not clear in breast cancer, a diverse expression pattern of ALCAM mRNA was detected in a panel of breast cancer patient samples. Differentially expressed/regulated cancer-related genes upon miR-125b expression along with the significant increase of ALCAM are of future interest to understand how deregulated expression of miR-125b may have a tumor suppressor role in breast and other cancers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, CD / biosynthesis*
  • Antigens, CD / genetics
  • Breast Neoplasms / genetics*
  • Breast Neoplasms / pathology
  • Cell Adhesion Molecules, Neuronal / biosynthesis*
  • Cell Adhesion Molecules, Neuronal / genetics
  • Female
  • Fetal Proteins / biosynthesis*
  • Fetal Proteins / genetics
  • Gene Expression Regulation, Neoplastic / genetics
  • Humans
  • MCF-7 Cells
  • MicroRNAs / biosynthesis*
  • MicroRNAs / genetics
  • RNA, Messenger / biosynthesis

Substances

  • ALCAM protein, human
  • Antigens, CD
  • Cell Adhesion Molecules, Neuronal
  • Fetal Proteins
  • MIRN125 microRNA, human
  • MicroRNAs
  • RNA, Messenger