title: [Role of oxidative stress and thioredoxin in gastric cancer].
abstract: OBJECTIVE
  To explore the role of oxidative stress and the antioxidant protein thioredoxin in the tumorigenesis and progression of gastric cancer.
  
  
  METHODS
  The plasma levels of adenosine deaminase (ADA), glutathione peroxidase (GPX), superoxide dismutase (SOD), and advanced oxidation protein products (AOPP) were determined by colorimetry, and the plasma levels of thioredoxin were determined by enzyme-linked immunosorbent assay (ELISA) in 48 gastric cancer patients and 30 healthy subjects. RT-PCR assay was employed to examine the expression levels of thioredoxin mRNA in the tissue samples of the patients.
  
  
  RESULTS
  Compared with the healthy controls, patients with gastric cancer had significantly increased plasma levels of ADA and AOPP (P<0.05), decreased plasma GPX level (P<0.05), and similar plasma SOD levels. The plasma levels of thioredoxin were significantly higher in patients with gastric cancer than in the healthy controls (P<0.05). Thioredoxin levels was not associated with gender, age, degree of tumor cell differentiation, invasion depth, or lymph node metastasis (P>0.05), but was correlated to distant tumor metastasis (P<0.05). The expression of Trx mRNA was significantly higher in gastric carcinoma than in normal gastric tissue (P<0.05).
  
  
  CONCLUSIONS
  Gastric cancer patients have high levels of oxidative stress and thioredoxin expression, and the latter is related to distant metastasis of the tumor.
authors.affiliation: Department of Clinical Oncology, Xi'an Jiaotong University College of Medicine, Xi'an 710061, China. tuhonglei2009@163.com
authors.forename: Hong-lei
authors.initials: HL
authors.lastname: Tu
authors.forename: Ju-xiang
authors.initials: JX
authors.lastname: Xiao
authors.forename: Hai-bing
authors.initials: HB
authors.lastname: Sun
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Lin
authors.forename: Yong-chang
authors.initials: YC
authors.lastname: Wei
mesh_terms: D000243:Adenosine Deaminase / Q000097:blood; D000328:Adult; D062107:Advanced Oxidation Protein Products / Q000097:blood; D000368:Aged; D016022:Case-Control Studies; D005260:Female; D005979:Glutathione Peroxidase / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D018384:Oxidative Stress; D012333:RNA, Messenger / Q000235:genetics; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000473:pathology; D013482:Superoxide Dismutase / Q000097:blood; D013879:Thioredoxins / Q000235:genetics / Q000378:metabolism*
chemical_list: D062107:Advanced Oxidation Protein Products; D012333:RNA, Messenger; D013879:Thioredoxins; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D000243:Adenosine Deaminase