title: Serum levels of selenium and smoking habits at age 50 influence long term prostate cancer risk; a 34 year ULSAM follow-up.
abstract: BACKGROUND
  Serum selenium level (s-Se) has been associated with prostate cancer (PrCa) risk. We investigated the relation between s-Se, smoking and non-screening detected PrCa and explored if polymorphisms in two DNA repair genes: OGG1 and MnSOD, influenced any effect of s-Se.
  
  
  METHODS
  ULSAM, a population based Swedish male cohort (n = 2322) investigated at age 50 for s-Se and s-Se influencing factors: serum cholesterol, erythrocyte sedimentation rate and smoking habits. At age 71 a subcohort, (n = 1005) was genotyped for OGG1 and MnSOD polymorphisms.
  
  
  RESULTS
  In a 34-year-follow-up, national registries identified 208 PrCa cases further confirmed in medical records. Participants with s-Se in the upper tertile had a non-significantly lower risk of PrCa. Smokers with s-Se in the two lower tertiles (≤80 μg/L) experienced a higher cumulative incidence of PrCa than smokers in the high selenium tertile (Hazard Ratio 2.39; 95% CI: 1.09-5.25). A high tertile selenium level in combination with non-wt rs125701 of the OGG1 gene in combination with smoking status or rs4880 related variation of MnSOD gene appeared to protect from PrCa.
  
  
  CONCLUSIONS
  S-Se levels and smoking habits influence long-term risk of PrCa. Smoking as a risk factor for PrCa in men with low s-Se is relevant to explore further. Exploratory analyses of variations in OGG1 and MnSOD genes indicate that hypotheses about patterns of exposure to selenium and smoking combined with data on genetic variation in genes involved in DNA repair can be valuable to pursue.
authors: Department of Surgical Sciences, Uppsala University, Uppsala, Sweden. birgitta.grundmark@surgsci.uu.se
authors: Birgitta
authors: B
authors: Grundmark
authors: Björn
authors: B
authors: Zethelius
authors: Hans
authors: H
authors: Garmo
authors: Lars
authors: L
authors: Holmberg
mesh_terms: D000368:Aged; D045647:DNA Glycosylases / Q000235:genetics; D005500:Follow-Up Studies; D005838:Genotype; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000235:genetics / Q000378:metabolism; D018570:Risk Assessment; D012643:Selenium / Q000097:blood*; D012907:Smoking; D013482:Superoxide Dismutase / Q000235:genetics
chemical_list: D013482:Superoxide Dismutase; D045647:DNA Glycosylases; C479058:oxoguanine glycosylase 1, human; D012643:Selenium