title: In vitro cellular response of retinoic acid treated human oral cancer cell lines.
abstract: BACKGROUND
  The purpose of this study is to identify the cellular response ofretinoic acid-treated human oral cancer cell lines.
  
  
  METHODS
  Seven human oral cancer cell lines KB, SCC4, SCC9, SCC15, SCC25, OEC-M1, OC1 and OC2 were used for cell culture experiments. Direct cell number counting method was utilized to evaluate cellular response of these human oral cancer cells at the presence or absence of all-trans RA at 1 mM.
  
  
  RESULTS
  Through 7-day observation, the cell population of SCC9, SCC15 and SCC25 of RA-treated groups decreased when compared with the non RA-treated groups. These three cell lines were further verified using [3H] thymidine incorporation DNA synthesis assay. KB, SCC4, OC1, OC2 and OEC-M1 cell lines did not show growth inhibition at the presence of RA at 1 mM.
  
  
  CONCLUSIONS
  The molecular event of how SCC9, SCC15 and SCC25 are inhibited by RA and how KB, OC1, OC2 and OECM1 are resistant to RA can be further explored on the basis of this study.
authors.affiliation: Department of Dentistry, Taipei Veterans General Hospital, Taiwan, ROC.
authors.forename: C C
authors.initials: CC
authors.lastname: Yang
authors.forename: S F
authors.initials: SF
authors.lastname: Tu
authors.forename: R C
authors.initials: RC
authors.lastname: Chang
authors.forename: S Y
authors.initials: SY
authors.lastname: Kao
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000188:drug therapy* / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D004247:DNA / Q000096:biosynthesis; D006801:Humans; D009062:Mouth Neoplasms / Q000188:drug therapy* / Q000473:pathology; D013936:Thymidine / Q000378:metabolism; D014212:Tretinoin / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
chemical_list: D014212:Tretinoin; D004247:DNA; D013936:Thymidine