CacyBP/SIP protein is important for the proliferation of human glioma cells

IUBMB Life. 2014 Apr;66(4):286-91. doi: 10.1002/iub.1263. Epub 2014 Apr 17.


Recently, calcyclin-binding protein or Siah-1-interacting protein (CacyBP/SIP), a component of a novel ubiquitinylation pathway, could regulate the β-catenin degradation (Fukushima et al., Immunity 2006, 24, 29-39). However, the potential role of CacyBP/SIP itself in human glioma cells has not been clarified. Here, we found that CacyBP/SIP was expressed highly in human glioma tissues. Silencing of CacyBP/SIP by short-hairpin RNA severely suppressed the proliferation of human glioma cell U251, which was at least partly mediated by downregulation of phospho-Akt (p-Akt) and phospho-β-catenin (p-β-catenin) as well as upregulation of p53 and p21. Furthermore, overexpression of CacyBP/SIP obviously promoted the proliferation of human glioma U251, which exhibited the exactly contrary trend in the expression of p-Akt, p-β-catenin, p53, and p21. Taken together, these findings suggest that CacyBP/SIP plays important roles in the proliferation of human glioma cell which might be involved in the development of human glioma.

Keywords: CacyBP/SIP; cell cycle; glioma; proliferation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blotting, Western
  • Brain / metabolism*
  • Brain Neoplasms / metabolism
  • Brain Neoplasms / pathology*
  • Calcium-Binding Proteins / antagonists & inhibitors
  • Calcium-Binding Proteins / genetics
  • Calcium-Binding Proteins / metabolism*
  • Cell Cycle
  • Cell Proliferation*
  • Flow Cytometry
  • Glioma / metabolism
  • Glioma / pathology*
  • Humans
  • RNA, Small Interfering / genetics
  • Tumor Cells, Cultured


  • CACYBP protein, human
  • Calcium-Binding Proteins
  • RNA, Small Interfering