Inhibition of invasion and induction of apoptosis by selenium in human malignant brain tumour cells in vitro

Int J Oncol. 2007 May;30(5):1263-71.


Selenium is considered to be one of the most promising micronutrients for cancer prevention and therapy, based on evidence from epidemiological studies, laboratory-based research and clinical trial intervention. There are ample reports of selenium methionine and sodium selenite's ability to induce apoptosis in various cancers in vitro. There are a few reports in the literature on the effects of selenium on established glioma cell lines but none on biopsy-derived short-term brain tumour cultures. In this in vitro study the effects of a range of concentrations (2-10 microg/ml) of sodium selenite were investigated in one low-passage culture of biopsy-derived glioma cells (IPSB-18, an anaplastic astrocytoma, P 18-22) and a normal human brain cell culture (CC2565, P11). Results from 2 viability assays, 3[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) and sulphorodamine B (SRB) consistently showed that the IC50 for selenium in the astrocytoma was approximately 5 microg/ml whilst the normal brain cells were unaffected by selenium in the range of concentrations studied. Time-lapse video microscopy revealed that, while at 4 microg/ml selenium, the time taken to achieve 100% cell death was 17 h, with increasing concentrations of selenium from 6 to 8 microg/ml and finally at 10 microg/ml the IPSB-18 cells rounded up and died much more quickly. The time taken to achieve 100% cell death was 7 h, 7 h and 6 h, respectively, suggesting that the effect was similar at higher concentrations. Flow cytometry indicated that cell death was by apoptosis. RT-PCR results showed downregulation of the gene expression of 6 matrix metalloproteases (MMP2, 9, 14, 15, 16, 24), their inhibitors, TIMPs and epidermal growth factor receptor, in IPSB-18 cells treated with 2, 4 and 8 microg/ml of selenium. Collectively, the data in this study suggests that selenium, not only induces tumour cell-specific apoptosis but also has anti-invasive potential.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Antineoplastic Agents / pharmacology
  • Apoptosis*
  • Astrocytoma / drug therapy*
  • Astrocytoma / pathology
  • Brain Neoplasms / drug therapy*
  • Brain Neoplasms / pathology
  • Cell Line, Tumor
  • Cell Survival
  • Dose-Response Relationship, Drug
  • Humans
  • In Vitro Techniques
  • Inhibitory Concentration 50
  • Male
  • Neoplasm Invasiveness
  • RNA / metabolism
  • Selenium / pharmacology*
  • Tetrazolium Salts / pharmacology
  • Thiazoles / pharmacology


  • Antineoplastic Agents
  • Tetrazolium Salts
  • Thiazoles
  • RNA
  • thiazolyl blue
  • Selenium