Mechanistic insights of O-GlcNAcylation that promote progression of cholangiocarcinoma cells via nuclear translocation of NF-κB

Sci Rep. 2016 Jun 13:6:27853. doi: 10.1038/srep27853.

Abstract

O-GlcNAcylation, an O-linked protein glycosylation with a single molecule of N-acetylglucosamine (GlcNAc), is reversibly controlled by O-GlcNAc transferase (OGT) and N-acetyl D-glucosaminidase (OGA). Aberrant O-GlcNAcylation contributes an important role in initiation and progression of many human cancers. Elevation of O-GlcNAcylation in tumor tissues and poor prognosis of cholangiocarcinoma (CCA) patients have been reported. In this study, the role of O-GlcNAcylation in promoting tumor progression was further investigated in CCA cell lines. Suppression of O-GlcNAcylation using small interfering RNAs of OGT (siOGT) significantly reduced cell migration and invasion of CCA cells whereas siOGA treated cells exhibited opposite effects. Manipulating levels of O-GlcNAcylation did affect the nuclear translocation of NF-κB and Akt-phosphorylation together with expression of matrix-metalloproteinases (MMPs). O-GlcNAcylation and nuclear translocation of NF-κB, the upstream signaling cascade of MMP activation were shown to be important for MMP activation. Immunoprecipitation revealed the elevation of O-GlcNAc-modified NF-κB with increased cellular O-GlcNAcylation. Involvement of O-GlcNAcylation in MMP-mediated migration and invasion of CCA cells was shown to be via O-GlcNAcylation and nuclear translocation of NF-κB. This information indicates the significance of O-GlcNAcylation in controlling the metastatic ability of CCA cells, hence, O-GlcNAcylation and its products may be new targets for treatment of metastatic CCA.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bile Duct Neoplasms / metabolism
  • Bile Duct Neoplasms / pathology
  • Cell Line, Tumor
  • Cell Movement
  • Cell Proliferation
  • Cholangiocarcinoma / metabolism
  • Cholangiocarcinoma / pathology
  • Glycosylation
  • Humans
  • Immunoprecipitation
  • Matrix Metalloproteinases / metabolism
  • N-Acetylglucosaminyltransferases / antagonists & inhibitors
  • N-Acetylglucosaminyltransferases / genetics
  • N-Acetylglucosaminyltransferases / metabolism
  • NF-kappa B / metabolism*
  • Phosphorylation
  • Proto-Oncogene Proteins c-akt / metabolism
  • RNA Interference
  • RNA, Small Interfering / metabolism
  • Transcription Factor RelA / metabolism

Substances

  • NF-kappa B
  • RNA, Small Interfering
  • Transcription Factor RelA
  • N-Acetylglucosaminyltransferases
  • O-GlcNAc transferase
  • Proto-Oncogene Proteins c-akt
  • Matrix Metalloproteinases