MiR-200c increases the radiosensitivity of non-small-cell lung cancer cell line A549 by targeting VEGF-VEGFR2 pathway

PLoS One. 2013 Oct 30;8(10):e78344. doi: 10.1371/journal.pone.0078344. eCollection 2013.

Abstract

MicroRNAs (miRNAs) have been demonstrated to participate in many important cellular processes including radiosensitization. VEGF family, an important regulator of angiogenesis, also plays a crucial role in the regulation of cancer cell radiosensitivity. VEGFR2 mediates the major growth and permeability actions of VEGF in a paracrine/autocrine manner. MiR-200c, at the nexus of epithelial-mesenchymal transition (EMT), is predicted to target VEGFR2. The purpose of this study is to test the hypothesis that regulation of VEGFR2 pathway by miR-200c could modulate the radiosensitivity of cancer cells. Bioinformatic analysis, luciferase reporter assays and biochemical assays were carried out to validate VEGFR2 as a direct target of miR-200c. The radiosensitizing effects of miR-200c on A549 cells were determined by clonogenic assays. The downstream regulating mechanism of miR-200c was explored with western blotting assays, FCM, tube formation assays and migration assays. We identified VEGFR2 as a novel target of miR-200c. The ectopic miR-200c increased the radiosensitivity of A549 while miR-200c down-regulation decreased it. Besides, we proved that miR-200c radiosensitized A549 cells by targeting VEGF-VEGFR2 pathway specifically, thus leading to inhibition of its downstream pro-survival signaling transduction and angiogenesis, and serves as a potential target for radiosensitizition research.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carcinoma, Non-Small-Cell Lung / genetics*
  • Cell Line, Tumor
  • Down-Regulation / genetics
  • Gene Expression Regulation, Neoplastic / genetics
  • Humans
  • Lung Neoplasms / genetics
  • MicroRNAs / genetics*
  • Radiation Tolerance / genetics*
  • Signal Transduction / genetics*
  • Vascular Endothelial Growth Factor A / genetics*
  • Vascular Endothelial Growth Factor Receptor-2 / genetics*

Substances

  • MIRN200 microRNA, human
  • MicroRNAs
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • KDR protein, human
  • Vascular Endothelial Growth Factor Receptor-2

Grants and funding

This work was supported by Hubei Provincial Natural Science Foundation project (No: 2009CDA061). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.