title: Determination of gene expression and serum levels of MnSOD and GPX1 in colorectal cancer.
abstract: OBJECTIVE
  Oxidative stress plays a role on the development of colorectal cancer. Manganese superoxide dismutase (MnSOD) and glutathione peroxidase 1 (GPX1) are crucial in regulating oxidative balance and its stabilization. Possible mechanisms of action of these enzymes in various types of cancers require further investigation. We aimed to determine expression levels of these genes and their effects on protein levels in serum of patients with colorectal cancer.
  
  
  METHODS
  Expression levels of genes were determined using Real Time-Polymerase chain reaction in 35 patients with colorectal cancer. We used enzyme-linked immunosorbent assay to determine MnSOD and GPX1 levels.
  
  
  RESULTS
  We found significant differences in GPX1 expression between tumor and normal tissues, with a 2-fold decrease in tumor tissues (p<0.05). However, although no significant difference was found between the expression of MnSOD gene in tumor and that in normal tissues, there was a 1.13-fold change in expression. We observed no relationship between expressions of either gene and their levels in serum.
  
  
  CONCLUSIONS
  The GPX1 gene may play a critical role in the development of colorectal cancer.
authors.affiliation: Faculty of Medicine, Department of Medical Biology, Recep Tayyip Erdogan University, Rize, Turkey.
authors.forename: Ihsan
authors.initials: I
authors.lastname: Nalkiran
authors.affiliation: Department of Molecular Medicine, Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Saime
authors.initials: S
authors.lastname: Turan
authors.affiliation: General Surgery Clinic, Istanbul Education and Research Hospital, Istanbul, Turkey.
authors.forename: Soykan
authors.initials: S
authors.lastname: Arikan
authors.affiliation: Department of Molecular Medicine, Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Özlem Timirci
authors.initials: ÖT
authors.lastname: Kahraman
authors.affiliation: Department of Molecular Medicine, Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Leyla
authors.initials: L
authors.lastname: Acar
authors.affiliation: Department of Molecular Medicine, Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey.
authors.forename: Ilhan
authors.initials: I
authors.lastname: Yaylim
authors.affiliation: Department of Molecular Medicine, Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey a_ergen@yahoo.com.
authors.forename: Arzu
authors.initials: A
authors.lastname: Ergen
mesh_terms: D000368:Aged; D015179:Colorectal Neoplasms / Q000097:blood / Q000201:enzymology*; D005260:Female; D015870:Gene Expression; D005979:Glutathione Peroxidase / Q000097:blood* / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D013482:Superoxide Dismutase / Q000097:blood* / Q000235:genetics; D000094765:Glutathione Peroxidase GPX1; D000099156:Superoxide Dismutase 2
chemical_list: D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D000094765:Glutathione Peroxidase GPX1; D000099156:Superoxide Dismutase 2; C000722067:GPX1 protein, human
keywords: GPX1; MnSOD; antioxidants; colorectal cancer; oxidative stress