title: Growth inhibition of epidermal growth factor-stimulated human glioblastoma cells by nicardipine in vitro.
abstract: BACKGROUND
  The objective of this work was to observe and analyze the effects of epidermal growth factor (EGF) and the calcium channel antagonist nicardipine on the growth of U251MG, a human malignant glioma cell line, which have high-affinity EGF receptors.
  
  
  METHODS
  The growth effects of EGF and nicardipine on U251MG cultured in serum-free and serum-supplemented (10% fetal bovine serum, FBS) medium respectively were observed by MTT colorimeritric analysis.
  
  
  RESULTS
  EGF significantly enhanced the growth of U251MG cells in a dose-dependent manner in serum-free medium. The maximal effect was seen at 20 ng/ml. The effects of EGF approximated those obtained in 10% FBS. Nicardipine decreased U251MG cell proliferation, especially in serum-supplemented medium, and completely blocked the growth-stimulated effects of EGF. The combined effects of EGF (10 ng/ml) and nicardipine equaled those of nicardipine alone.
  
  
  CONCLUSIONS
  When serum was absent, the U251MG cells showed a pronounced mitogenic response to EGF in a dose-dependent manner, which approximated that achieved with 10% FBS. The addition of serum obscured this effect. Nicardipine suppressed the growth of U251MG cells and completely blocked the growth-stimulated effects of EGF may suggest a possible role of this drug as adjuvant therapy for human malignant gliomas.
authors.affiliation: Department of Neurosurgery, Hainan Provincial, People's Hospital, Haikou, China.
authors.forename: C
authors.initials: C
authors.lastname: Huang
authors.forename: S
authors.initials: S
authors.lastname: Hu
authors.forename: B
authors.initials: B
authors.lastname: Chen
mesh_terms: D002121:Calcium Channel Blockers / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004815:Epidermal Growth Factor / Q000494:pharmacology*; D005909:Glioblastoma / Q000473:pathology*; D006801:Humans; D009529:Nicardipine / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
chemical_list: D002121:Calcium Channel Blockers; D004815:Epidermal Growth Factor; D009529:Nicardipine