Silencing of NRAGE induces autophagy via AMPK/Ulk1/Atg13 signaling pathway in NSCLC cells

Tumour Biol. 2017 Jun;39(6):1010428317709676. doi: 10.1177/1010428317709676.

Abstract

NRAGE has been reported to be overexpressed in cancer cells, especially in lung cancer cells. To determine the role of NRAGE in non-small-cell lung cancer cells, we investigated the effects of NRAGE on autophagy in non-small-cell lung cancer cells. Human A549 and H1299 cells were transfected with NRAGE-specific small-interfering RNA. The Cell Counting Kit-8 and plate clone assay showed that downregulation of NRAGE could induce the proliferation in A549 and H1299 cells. In addition, our data suggested that downregulation of NRAGE enhances autophagosome formation by immunofluorescence. We found that knockdown of NRAGE induced autophagy, together with downregulation of P62 and upregulation of LC3-II protein. Furthermore, to elucidate the mechanism of NRAGE in suppressing autophagy, the protein expressions of AMPK, Ulk1, and Atg13 were assessed. Collectively, these results demonstrate the effective anti-autophagic of NRAGE in non-small-cell lung cancer cells through AMPK/Ulk1/Atg13 autophagy signaling pathways. Therefore, NRAGE could be used as a potential therapeutic target for lung cancer.

Keywords: AMPK/Ulk1/Atg13 signaling pathway; NRAGE; autophagy; non-small-cell lung cancer; proliferation.

MeSH terms

  • A549 Cells
  • AMP-Activated Protein Kinases / biosynthesis
  • AMP-Activated Protein Kinases / genetics*
  • Adaptor Proteins, Signal Transducing / biosynthesis
  • Adaptor Proteins, Signal Transducing / genetics*
  • Antigens, Neoplasm / genetics*
  • Autophagy / genetics
  • Autophagy-Related Protein-1 Homolog / biosynthesis
  • Autophagy-Related Protein-1 Homolog / genetics*
  • Autophagy-Related Proteins / biosynthesis
  • Autophagy-Related Proteins / genetics*
  • Carcinoma, Non-Small-Cell Lung / genetics*
  • Carcinoma, Non-Small-Cell Lung / pathology
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Intracellular Signaling Peptides and Proteins / biosynthesis
  • Intracellular Signaling Peptides and Proteins / genetics*
  • Neoplasm Proteins / antagonists & inhibitors
  • Neoplasm Proteins / genetics*
  • Phosphorylation
  • RNA, Small Interfering
  • Signal Transduction

Substances

  • ATG13 protein, human
  • Adaptor Proteins, Signal Transducing
  • Antigens, Neoplasm
  • Autophagy-Related Proteins
  • Intracellular Signaling Peptides and Proteins
  • MAGED1 protein, human
  • Neoplasm Proteins
  • RNA, Small Interfering
  • Autophagy-Related Protein-1 Homolog
  • ULK1 protein, human
  • AMP-Activated Protein Kinases