title: Effect of three fluoride compounds on the growth of oral normal and tumor cells.
abstract: OBJECTIVE
  Comparative study of the growth inhibition by different types of fluoride compounds used in dentistry has been limited. We investigated the effects of sodium fluoride (NaF), diammine silver fluoride [Ag(NH3)2F] and 5-fluorouracil (5-FU) on the growth of eleven human normal and tumor cells in total.
  
  
  METHODS
  Viable cell number was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis induction was evaluated by caspase-3 activation and DNA fragmentation. Fluoride was determined using a fluoride-specific electrode.
  
  
  RESULTS
  All compounds had little or no growth stimulating effect (hormesis) on all cells. Ag(NH3)2F exhibited the highest cytotoxicity towards both normal and tumor cells. 5-FU had the selective cytostatic activity towards oral squamous cell carcinoma cell lines, whereas NaF was selectively cytotoxic towards glioblastoma cell lines. None of the compounds induced internucleosomal DNA fragmentation and only 5-FU induced slight activation of caspase-3 in an oral squamous cell carcinoma cell line (HSC-2). Cytotoxicity of fluoride compounds was not reduced by superoxide dismutase and catalase, reducing the possibility of the involvement of reactive oxygen species in the mechanism of action. Approximately 0.01-0.09% initially added NaF was recovered from the cells, whereas the cellular uptake of Ag(NH3)2F and 5-FU was below the detection limit.
  
  
  CONCLUSIONS
  Cytotoxicity of fluoride compounds may not be directly linked to their tumor specificity nor to their apoptosis-inducing activity.
authors: Division of Pharmacology, Department of Diagnostic and Therapeutic Sciences, Meikai University School of Dentistry, Sakado, Saitama 350-0283, Japan. alexmenaacra@gmail.com
authors: Alejandro Mena
authors: AM
authors: Acra
authors: Hiroshi
authors: H
authors: Sakagami
authors: Tomohiko
authors: T
authors: Matsuta
authors: Kazunori
authors: K
authors: Adachi
authors: Sumiko
authors: S
authors: Otsuki
authors: Hiroshi
authors: H
authors: Nakajima
authors: Teho
authors: T
authors: Koh
authors: Mamoru
authors: M
authors: Machino
authors: Takashi
authors: T
authors: Ogihara
authors: Koji
authors: K
authors: Watanabe
authors: Shigeru
authors: S
authors: Watanabe
authors: Angel Visoso
authors: AV
authors: Salgado
authors: Norma M Montiel
authors: NM
authors: Bastida
mesh_terms: D002455:Cell Division / Q000187:drug effects*; D002478:Cells, Cultured; D005459:Fluorides / Q000494:pharmacology*; D006801:Humans; D009055:Mouth / Q000166:cytology / Q000187:drug effects*; D009062:Mouth Neoplasms / Q000473:pathology*; D014407:Tumor Cells, Cultured
chemical_list: D005459:Fluorides