title: Synergistic effect of sorafenib with ionizing radiation on human oral cancer cells.
abstract: OBJECTIVE
  Although anticancer effects of sorafenib on renal, liver and colon carcinomas are well-known, its combination effect with ionizing radiation on oral squamous cell carcinoma (OSCC) is unclear. Herein human SAS cells, an OSCC cell line, were used in order to elucidate this combination effect.
  
  
  METHODS
  Both SAS and SAS/nuclear factor kappa-B-luciferase (SAS/NF-κB-luc2) cell lines were used in the study. Cell viability, NF-κB activation, and protein expression of NF-κB downstream effectors were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, NF-κB-luc2 reporter gene system, NF-κB/DNA binding activity and western blotting.
  
  
  RESULTS
  Sorafenib significantly increased radiation-induced cytotoxicity and apoptosis via both mitochondrial-dependent and independent pathways. In addition, NF-κB activity and downstream effector protein expression induced by radiation was suppressed by sorafenib in SAS/NF-κB-luc2 cells.
  
  
  CONCLUSIONS
  Combination of sorafenib with radiation for the treatment of human OSCC shows a synergistic effect via suppression of radiation-induced NF-κB activity and its regulated downstream effector proteins.
authors.affiliation: Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Bei-tou, Taipei, Taiwan, R.O.C.
authors.forename: Fei-Ting
authors.initials: FT
authors.lastname: Hsu
authors.affiliation: Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Bei-tou, Taipei, Taiwan, R.O.C.
authors.forename: Betty
authors.initials: B
authors.lastname: Chang
authors.affiliation: Department of Radiological Technology, Central Taiwan University of Science and Technology, Beitun, Taichung, Taiwan, R.O.C.
authors.forename: I-Tsang
authors.initials: IT
authors.lastname: Chiang
authors.affiliation: Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Bei-tou, Taipei, Taiwan, R.O.C.
authors.forename: Tai-Hsien
authors.initials: TH
authors.lastname: Wu
authors.affiliation: Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Bei-tou, Taipei, Taiwan, R.O.C. jjhwang@ym.edu.tw.
authors.forename: Jeng-Jong
authors.initials: JJ
authors.lastname: Hwang
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects / Q000528:radiation effects; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D009062:Mouth Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism; D009536:Niacinamide / Q000031:analogs & derivatives* / Q000494:pharmacology; D010671:Phenylurea Compounds / Q000494:pharmacology*; D010766:Phosphorylation / Q000187:drug effects; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D011836:Radiation Tolerance / Q000187:drug effects*; D011839:Radiation, Ionizing; D000077157:Sorafenib
chemical_list: D000970:Antineoplastic Agents; D016328:NF-kappa B; D010671:Phenylurea Compounds; D047428:Protein Kinase Inhibitors; D009536:Niacinamide; D000077157:Sorafenib
keywords: NF-κB; Sorafenib; human oral squamous cell carcinoma; radiation