title: Selenium and selenomethionine levels in prostate cancer patients.
abstract: OBJECTIVE
  Selenium (Se) and selenomethionine (Se-Met) have been identified as potential chemopreventive agents of prostate cancer. Using an assay for the speciation (separation and identification) and quantification of selenoamino acids, Se-Met was profiled in serum and prostate tissue from prostate cancer patients. Total Se was measured also.
  
  
  METHODS
  Serum and prostate tissue samples were analyzed using high performance liquid chromatography ion channel plasma-mass spectrometry (HPLC ICP-MS). Samples were provided by 25 subjects undergoing radical prostatectomy for the treatment of prostate cancer.
  
  
  RESULTS
  The mean serum Se-Met concentration was 59.4 +/- 19.5 ng/ml. Mean total serum Se levels were 133.8 +/- 29.2 ng/ml. Total Se levels in paired samples from the transitional and peripheral zones of the prostate were also compared. Total mean Se levels in peripheral zone tissue was higher than in transitional zone tissue (0.432 +/- 0.212 microg/g versus 0.293 +/- 0.172 microg/g, P = 0.01). Se-Met was detected in the majority of prostate tissues.
  
  
  CONCLUSIONS
  This group of prostate cancer patients had total Se levels in serum and in prostate tissue in a range expected for normal Se intake. There was a significantly higher total Se level found in peripheral versus transitional zone tissues. This is the first time that Se-Met has been detected in prostate tissue.
authors.affiliation: Department of Pharmacology/Toxicology, University of Arizona Health Sciences Center, Tucson, AZ 85721-0207, USA. nyman@pharmacy.arizona.edu
authors.forename: David W
authors.initials: DW
authors.lastname: Nyman
authors.forename: M
authors.initials: M
authors.lastname: Suzanne Stratton
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Kopplin
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Dalkin
authors.forename: Raymond B
authors.initials: RB
authors.lastname: Nagle
authors.forename: A
authors.initials: A
authors.lastname: Jay Gandolfi
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis*; D001707:Biopsy, Needle; D002851:Chromatography, High Pressure Liquid; D003430:Cross-Sectional Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011468:Prostatectomy / Q000379:methods; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology* / Q000601:surgery; D012016:Reference Values; D012494:Sampling Studies; D012643:Selenium / Q000032:analysis / Q000378:metabolism*; D012645:Selenomethionine / Q000032:analysis / Q000378:metabolism*; D012680:Sensitivity and Specificity
chemical_list: D014408:Biomarkers, Tumor; D012645:Selenomethionine; D012643:Selenium