title: Role of pretherapeutic biomarkers in predicting postoperative radiotherapy response in patients with advanced squamous cell carcinoma.
abstract: OBJECTIVE
  To assess the role of biomarker levels in predicting radiotherapy (RT) response in patients with squamous cell carcinoma of buccal mucosa treated with postoperative RT.
  
  
  METHODS
  Thirty-one patients with squamous cell carcinoma of buccal mucosa who received postoperative RT were enrolled for the study. Glutathione S-transferase (GST), glutathione reductase (GR), superoxide dismutase (SOD) and catalase activity were analysed from primary tumour and adjacent normal mucosa of the same patients before RT. p53 and p21ras were localized immunohistochemically.
  
  
  RESULTS
  Enzyme activation was predicted by comparing the levels of these enzymes in tumour and adjacent normal mucosa. Deactivation of GST, activation of GR, SOD and catalase were associated with poor response to RT. p53 immunoreactivity was associated with failure to respond to RT.
  
  
  CONCLUSIONS
  These markers may be useful in predicting treatment outcome in patients receiving postoperative RT, although this conclusion requires confirmation in a larger group of patients.
authors.affiliation: Biochemistry Research Division, Department of Cancer Biology, The Gujarat Cancer and Research Institute, NCH Campus, Asarwa, Ahmedabad-380 016, India.
authors.forename: R M
authors.initials: RM
authors.lastname: Rawal
authors.forename: P S
authors.initials: PS
authors.lastname: Patel
authors.forename: R K
authors.initials: RK
authors.lastname: Vyas
authors.forename: R N
authors.initials: RN
authors.lastname: Sainger
authors.forename: M H
authors.initials: MH
authors.lastname: Shah
authors.forename: H M
authors.initials: HM
authors.lastname: Peshavariya
authors.forename: D D
authors.initials: DD
authors.lastname: Patel
authors.forename: J M
authors.initials: JM
authors.lastname: Bhatavdekar
mesh_terms: D015415:Biomarkers / Q000032:analysis*; D002294:Carcinoma, Squamous Cell / Q000532:radiotherapy* / Q000601:surgery*; D002374:Catalase / Q000032:analysis; D003131:Combined Modality Therapy; D017868:Cyclic AMP-Dependent Protein Kinases / Q000032:analysis; D005980:Glutathione Reductase / Q000032:analysis; D005982:Glutathione Transferase / Q000032:analysis; D006801:Humans; D008297:Male; D009061:Mouth Mucosa / Q000378:metabolism; D009062:Mouth Neoplasms / Q000532:radiotherapy* / Q000601:surgery*; D015689:Oncogene Protein p21(ras) / Q000032:analysis; D011184:Postoperative Period; D011237:Predictive Value of Tests; D011493:Protein Kinase C / Q000032:analysis; D012016:Reference Values; D013482:Superoxide Dismutase / Q000032:analysis; D016159:Tumor Suppressor Protein p53 / Q000032:analysis
chemical_list: D015415:Biomarkers; D016159:Tumor Suppressor Protein p53; D002374:Catalase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D005982:Glutathione Transferase; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C; D015689:Oncogene Protein p21(ras)