ErbB2-intronic microRNA-4728: a novel tumor suppressor and antagonist of oncogenic MAPK signaling.

Academic Article

Abstract

  • Although the role of the ErbB2/HER2 oncogene in cancers has been extensively studied, how ErbB2 is regulated remains poorly understood. A novel microRNA, mir-4728, was recently found within an intron of the ErbB2 gene. However, the function and clinical relevance of this intronic miRNA are completely unknown. Here, we demonstrate that mir-4728 is a negative regulator of MAPK signaling through directly targeting the ERK upstream kinase MST4 and exerts numerous tumor-suppressive properties in vitro and in animal models. Importantly, our patient sample study shows that mir-4728 was under-expressed in breast tumors compared with normal tissue, and loss of mir-4728 correlated with worse overall patient survival. These results strongly suggest that mir-4728 is a tumor-suppressive miRNA that controls MAPK signaling through targeting MST4, revealing mir-4728's significance as a potential prognostic factor and target for therapeutic intervention in cancer. Moreover, this study represents a conceptual advance by providing strong evidence that a tumor-suppressive miRNA can antagonize the canonical signaling of its host oncogene.
  • Published In

    Keywords

  • Breast Neoplasms, Cell Line, Tumor, Cell Proliferation, Female, Gene Expression Regulation, Neoplastic, Genes, Tumor Suppressor, HeLa Cells, Humans, Introns, MAP Kinase Signaling System, MicroRNAs, Mitogen-Activated Protein Kinase Kinases, Receptor, ErbB-2, Signal Transduction
  • Digital Object Identifier (doi)

    Author List

  • Schmitt DC; Madeira da Silva L; Zhang W; Liu Z; Arora R; Lim S; Schuler AM; McClellan S; Andrews JF; Kahn AG
  • Start Page

  • e1742
  • Volume

  • 6