Down-regulation of β-N-acetyl-D-glucosaminidase increases Akt1 activity in thyroid anaplastic cancer cells.

O-GlcNAcylation is a common and dynamic modification of intracellular proteins in which β-N-acetyl-glucosamine moieties are attached to hydroxyl groups of serine or threonine residues (O-GlcNAc). Accumulating evidence suggests the critical role of protein O-GlcNAcylation in signal transduction, transcriptional control, cell cycle regulation and protein degradation. However, the exact role of O-GlcNAc modification in tumor pathogenesis or progression remains to be established. In the present study, we investigated the effect of increased O-GlcNAcylation of cellular proteins on IGF‑1 signaling in 8305C thyroid anaplastic cancer cells. The global O-GlcNAc level in the 8305C cells was increased by down-regulation of β-N-acetyl-D-glucosaminidase (O-GlcNAcase) activity, an enzyme which removes O-GlcNAc moieties. We demonstrated here that IGF‑1 stimulates Akt1 activity in 8305C cells, and down-regulation of O-GlcNAcase activity by the chemical inhibitor PUGNAc or RNA interference method enhances this effect. Increased Akt1 activation increased cell proliferation. In cells with down-regulation of O-GlcNAcase activity, kinase GSK3β phosphorylation and cyclin D1 levels were higher than those in control cells. Our findings suggest that increased proliferation of 8305C cells treated with PUGNAc or RNAi against O-GlcNAcase at least partially depends on the IGF‑1-Akt1-GSK3β-cyclin D1 pathway.
AuthorsAnna Krześlak, Paweł Jóźwiak, Anna Lipińska
JournalOncology reports (Oncol Rep) Vol. 26 Issue 3 Pg. 743-9 (Sep 2011) ISSN: 1791-2431 [Electronic] Greece
PMID21637923 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
Chemical References
  • CCND1 protein, human
  • Oximes
  • Phenylcarbamates
  • N-acetylglucosaminono-1,5-lactone O-(phenylcarbamoyl)oxime
  • Cyclin D1
  • Insulin-Like Growth Factor I
  • AKT1 protein, human
  • Proto-Oncogene Proteins c-akt
  • glycogen synthase kinase 3 beta
  • Glycogen Synthase Kinase 3
  • beta-N-Acetylhexosaminidases
  • Acetylglucosamine
  • Acetylglucosamine (analogs & derivatives, pharmacology)
  • Cell Line, Tumor
  • Cell Proliferation
  • Cell Survival
  • Cyclin D1 (metabolism)
  • Down-Regulation
  • Glycogen Synthase Kinase 3 (metabolism)
  • Humans
  • Insulin-Like Growth Factor I (pharmacology, physiology)
  • Oximes (pharmacology)
  • Phenylcarbamates (pharmacology)
  • Phosphorylation
  • Proto-Oncogene Proteins c-akt (metabolism)
  • RNA Interference
  • Thyroid Neoplasms (metabolism)
  • beta-N-Acetylhexosaminidases (antagonists & inhibitors, genetics, metabolism)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research network!

Choose Username:
Verify Password: