MicroRNA-133a suppresses multiple oncogenic membrane receptors and cell invasion in non-small cell lung carcinoma

PLoS One. 2014 May 9;9(5):e96765. doi: 10.1371/journal.pone.0096765. eCollection 2014.

Abstract

Non-small cell lung cancers (NSCLCs) cause high mortality worldwide, and the cancer progression can be activated by several genetic events causing receptor dysregulation, including mutation or amplification. MicroRNAs are a group of small non-coding RNA molecules that function in gene silencing and have emerged as the fine-tuning regulators during cancer progression. MiR-133a is known as a key regulator in skeletal and cardiac myogenesis, and it acts as a tumor suppressor in various cancers. This study demonstrates that miR-133a expression negatively correlates with cell invasiveness in both transformed normal bronchial epithelial cells and lung cancer cell lines. The oncogenic receptors in lung cancer cells, including insulin-like growth factor 1 receptor (IGF-1R), TGF-beta receptor type-1 (TGFBR1), and epidermal growth factor receptor (EGFR), are direct targets of miR-133a. MiR-133a can inhibit cell invasiveness and cell growth through suppressing the expressions of IGF-1R, TGFBR1 and EGFR, which then influences the downstream signaling in lung cancer cell lines. The cell invasive ability is suppressed in IGF-1R- and TGFBR1-repressed cells and this phenomenon is mediated through AKT signaling in highly invasive cell lines. In addition, by using the in vivo animal model, we find that ectopically-expressing miR-133a dramatically suppresses the metastatic ability of lung cancer cells. Accordingly, patients with NSCLCs who have higher expression levels of miR-133a have longer survival rates compared with those who have lower miR-133a expression levels. In summary, we identified the tumor suppressor role of miR-133a in lung cancer outcome prognosis, and we demonstrated that it targets several membrane receptors, which generally produce an activating signaling network during the progression of lung cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carcinoma, Non-Small-Cell Lung / diagnosis
  • Carcinoma, Non-Small-Cell Lung / genetics
  • Carcinoma, Non-Small-Cell Lung / metabolism
  • Carcinoma, Non-Small-Cell Lung / pathology*
  • Cell Line, Tumor
  • Cell Proliferation
  • Down-Regulation / genetics
  • Gene Knockdown Techniques
  • Humans
  • Lung Neoplasms / diagnosis
  • Lung Neoplasms / genetics
  • Lung Neoplasms / metabolism
  • Lung Neoplasms / pathology*
  • MicroRNAs / genetics*
  • Neoplasm Invasiveness
  • Neoplasm Metastasis
  • Oncogene Proteins / genetics*
  • Prognosis
  • Proto-Oncogene Proteins c-akt / metabolism
  • Receptors, Cell Surface / genetics*
  • Signal Transduction / genetics

Substances

  • MIRN133 microRNA, human
  • MicroRNAs
  • Oncogene Proteins
  • Receptors, Cell Surface
  • Proto-Oncogene Proteins c-akt

Grants and funding

This work was supported by grants from the National Science Council (NSC101-2321-B-002-068-, NSC102-2321-B-002-053-, NSC102-2325-B-006-016-, and NSC99-2628-B-006-031-MY3, NSC102-2911-I-002-303). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.