title: Plasma glutathione S-transferase pi 1-1 AND alpha 1-1 levels in patients with bladder cancer.
abstract: OBJECTIVE
  Transitional cell carcinomas of the human bladder and many gastrointestinal tumors often contain high amounts of the detoxification enzyme glutathione S-transferase pi (GSTP1-1). Elevated levels of GSTP1-1 have been found in serum and plasma from patients with gastrointestinal, lung or head and neck cancer. GSTP1-1 and glutathione S-transferase alpha (GSTA1-1) have been reported to be increased in 10 of 15 patients (67%) with bladder cancer. We evaluate the role of GSTP1-1 and GSTA1-1 as plasma tumor markers in 50 patients with bladder cancer before and after treatment.
  
  
  METHODS
  Blood from patients with bladder cancer was sampled in ethylenediaminetetraacetic acid tubes. Plasma GSTA1-1 and GSTP1-1 were measured using the sensitive and specific sandwich enzyme-linked immunosorbent assay.
  
  
  RESULTS
  Respective plasma GSTA1-1 and GSTP1-1 levels were above the upper normal reference limit in 2 (4%) and 14 (28%) of the 50 patients with bladder cancer. No significant decrease in plasma GSTA1-1 or GSTP1-1 was noted in matched pairs of plasma samples collected before and after treatment.
  
  
  CONCLUSIONS
  In contrast to earlier reports, only a limited number of patients with bladder cancer had increased plasma GSTA1-1 or GSTP1-1, which did not decrease after tumor resection. These findings argue against the use of GSTP1-1 or GSTA1-1 as plasma markers for bladder cancer.
authors.affiliation: Department of Urology, Atrium Medical Center Heerlen, The Netherlands.
authors.forename: C L
authors.initials: CL
authors.lastname: Berendsen
authors.forename: T P
authors.initials: TP
authors.lastname: Mulder
authors.forename: W H
authors.initials: WH
authors.lastname: Peters
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D002295:Carcinoma, Transitional Cell / Q000175:diagnosis / Q000201:enzymology* / Q000628:therapy; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase / Q000097:blood*; D006801:Humans; D007527:Isoenzymes / Q000097:blood*; D008297:Male; D008875:Middle Aged; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis / Q000201:enzymology* / Q000628:therapy
chemical_list: D014408:Biomarkers, Tumor; D007527:Isoenzymes; C496556:GSTP1 protein, human; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase; C119995:glutathione S-transferase alpha