Crucial roles of RSK in cell motility by catalysing serine phosphorylation of EphA2

Nat Commun. 2015 Jul 9;6:7679. doi: 10.1038/ncomms8679.

Abstract

Crosstalk between inflammatory signalling pathways and receptor tyrosine kinases has been revealed as an indicator of cancer malignant progression. In the present study, we focus on EphA2 receptor tyrosine kinase, which is overexpressed in many human cancers. It has been reported that ligand-independent phosphorylation of EphA2 at Ser-897 is induced by Akt. We show that inflammatory cytokines promote RSK-, not Akt-, dependent phosphorylation of EphA2 at Ser-897. In addition, the RSK-EphA2 signalling pathway controls cell migration and invasion of metastatic breast cancer cells. Moreover, Ser-897-phosphorylated EphA2 co-localizes with phosphorylated active form of RSK in various human tumour specimens, and this double positivity is related to poor survival in lung cancer patients, especially those with a smoking history. Taken together, these results indicate that the phosphorylation of EphA2 at Ser-897 is controlled by RSK and the RSK-EphA2 axis might contribute to cell motility and promote tumour malignant progression.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Breast Neoplasms / genetics
  • Breast Neoplasms / metabolism
  • Carcinoma, Non-Small-Cell Lung / genetics
  • Carcinoma, Non-Small-Cell Lung / metabolism
  • Catalysis
  • Cell Line, Tumor
  • Cell Movement / genetics
  • Cytokines / metabolism*
  • Female
  • HEK293 Cells
  • HeLa Cells
  • Humans
  • Inflammation Mediators / metabolism
  • Liver Neoplasms / genetics
  • Liver Neoplasms / metabolism
  • Lung Neoplasms / genetics
  • Lung Neoplasms / metabolism
  • Male
  • Neoplasms / genetics
  • Neoplasms / metabolism
  • Phosphorylation
  • Prognosis
  • Prostatic Neoplasms / genetics
  • Prostatic Neoplasms / metabolism
  • Receptor, EphA2 / metabolism*
  • Ribosomal Protein S6 Kinases, 90-kDa / genetics*
  • Ribosomal Protein S6 Kinases, 90-kDa / metabolism
  • Serine / metabolism
  • Signal Transduction

Substances

  • Cytokines
  • Inflammation Mediators
  • Serine
  • Receptor, EphA2
  • RPS6KA1 protein, human
  • Ribosomal Protein S6 Kinases, 90-kDa
  • ribosomal protein S6 kinase, 90kDa, polypeptide 3