title: Determinants of oxidative stress and DNA damage (8-OhdG) in squamous cell carcinoma of head and neck.
abstract: BACKGROUND
  Squamous cell carcinoma of head and neck (SCCHN) is a major concern of health risk in developing countries, such as India. Apart from genetic configuration, environmental and lifestyle factors, as well as poor oral hygiene, provide free radical-generating environment, which may contribute to the development of cancer through DNA damage.
  
  
  METHODS
  Here we ascertained the various oxidative stress determinants in diagnosed SCCHN patients with health risk addictions. This study further evaluated the incremental effects inflicted by these lifestyle factors on redox status. The study included 100 consenting SCCHN patients and 90 matched healthy controls. Salivary total antioxidant capacity (TAC), glutathione (GSH), free radicals: such as reactive nitrogen species (RNS) and reactive oxygen species (ROS) along with oxidative DNA adduct (8-OHdG) were monitored.
  
  
  RESULTS
  Our findings indicated altered salivary oxidant-antioxidant status in SCCHN. A substantial rise in ROS (~2.0 folds) and RNS (~1.4 folds), together with significant lowering in TAC (~1.2 folds) and GSH (~1.7 folds) was observed. The 8-OHdG levels were also found to be considerably higher (P < 0.001) in salivary cell's DNA of these patients.
  
  
  CONCLUSIONS
  Our results demonstrate significant redox imbalance in cancer patients suggesting their paramount importance in the development of SCCHN.
authors.affiliation: CSIR-Indian Institute of Toxicology Research, Lucknow, India.
authors.forename: A
authors.initials: A
authors.lastname: Kumar
authors.forename: M C
authors.initials: MC
authors.lastname: Pant
authors.forename: H S
authors.initials: HS
authors.lastname: Singh
authors.forename: S
authors.initials: S
authors.lastname: Khandelwal
mesh_terms: D000080242:8-Hydroxy-2'-Deoxyguanosine; D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism*; D063646:Carcinogenesis; D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology; D004249:DNA Damage; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000378:metabolism; D005260:Female; D005978:Glutathione / Q000378:metabolism; D006258:Head and Neck Neoplasms / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D007194:India; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D026361:Reactive Nitrogen Species / Q000378:metabolism; D018987:Salivary Ducts / Q000378:metabolism* / Q000473:pathology
chemical_list: D014408:Biomarkers, Tumor; D026361:Reactive Nitrogen Species; D000080242:8-Hydroxy-2'-Deoxyguanosine; D003849:Deoxyguanosine; D005978:Glutathione