title: Can selenium levels act as a marker of colorectal cancer risk?
abstract: BACKGROUND
  Selenium has attracted attention because of its antioxidant properties. Antioxidants protects cells from damage. Certain breakdown products of selenium are believed to prevent tumor growth by enhancing the immune cell activity and suppressing the development of tumor blood vessels. In this observational study, selenium level was measured in a series of patients from Poland and Estonia to determine a correlation between levels of this microelement and colorectal cancer risk.
  
  
  METHODS
  A total of 169 colorectal cancer patients and 169 healthy controls were enrolled in the study after obtaining their informed consent. Selenium level in the blood serum was measured using Graphite Furnace Atomic Absorption Spectrometry (GFAAS). The statistical analysis was performed by Fisher's exact test.
  
  
  RESULTS
  The threshold point of selenium level was 55 μg/l and 65 μg/l for Poland and Estonia respectively, for an increase in cancer risk. The lower levels of selenium were associated with greater risk of colorectal cancer.
  
  
  CONCLUSIONS
  The result reveals a significant strong association between low selenium level and the colorectal cancer risk in both Estonian and Polish populations.
authors.affiliation: Department of Genetics and Pathology, International Hereditary Cancer Center, Pomeranian Medical University, Połabska 4, 70-115 Szczecin, Poland. marcinlener@poczta.onet.pl
authors.forename: Marcin R
authors.initials: MR
authors.lastname: Lener
authors.forename: Satish
authors.initials: S
authors.lastname: Gupta
authors.forename: Rodney J
authors.initials: RJ
authors.lastname: Scott
authors.forename: Martin
authors.initials: M
authors.lastname: Tootsi
authors.forename: Maria
authors.initials: M
authors.lastname: Kulp
authors.forename: Mari-Liis
authors.initials: ML
authors.lastname: Tammesoo
authors.forename: Anu
authors.initials: A
authors.lastname: Viitak
authors.forename: Anders
authors.initials: A
authors.lastname: Metspalu
authors.forename: Pablo
authors.initials: P
authors.lastname: Serrano-Fernández
authors.forename: Józef
authors.initials: J
authors.lastname: Kładny
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Jaworska-Bieniek
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Durda
authors.forename: Magdalena
authors.initials: M
authors.lastname: Muszyńska
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Sukiennicki
authors.forename: Anna
authors.initials: A
authors.lastname: Jakubowska
authors.forename: Jan
authors.initials: J
authors.lastname: Lubiński
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D016022:Case-Control Studies; D015179:Colorectal Neoplasms / Q000097:blood*; D004957:Estonia; D006801:Humans; D008875:Middle Aged; D016017:Odds Ratio; D011044:Poland; D012307:Risk Factors; D012643:Selenium / Q000097:blood*
chemical_list: D014408:Biomarkers, Tumor; D012643:Selenium