title: Superoxide dismutases and p53 protein levels in blood cells of breast cancer patients.
abstract: OBJECTIVE
  Radiation treatment of breast cancer (BC) often results in post-therapy complications. The undesired sequelae could be avoided by the diagnostic screening of biomarkers for prediction of ionizing radiation (IR)-linked injury of healthy tissues.
  
  
  METHODS
  The expression of antioxidative defence enzymes CuZn- and Mn-superoxide dismutase (CuZnSOD, MnSOD) and tumor suppressor protein p53 was measured in blood cells of 19 women with BC (age groups 30-45 and 46-60 years) and respective controls. The proteins were detected by specific immunostaining and quantified by laser-scanning densitometry.
  
  
  RESULTS
  Constitutive expression of CuZnSOD was significantly elevated in the group of BC patients (up to 254 arbitrary units, AU/mL) relative to the control group (105-130 AU/mL). The constitutive expression of MnSOD was elevated (up to 94 AU/mL) in the group of BC patients relative to the controls (53-56 AU/mL). p53 was also constitutively more expressed in BC patients (35-42 AU/mL) than in controls (32-33 AU/mL). Both MnSOD and p53 were inducible by (60)Co gamma-ray IR (up to 170 AU/mL and 51 AU/mL, respectively) in the BC patient group. The levels of IR-induced p53 correlated inversely with MnSOD levels.
  
  
  CONCLUSIONS
  The constitutive expression of all 3 proteins could be a useful biomarker for the presence of BC, but only MnSOD overexpression may be the predictive biomarker for selection of BC patients that would be less susceptible to IR-linked complications.
authors.affiliation: Laboratory of Molecular Biology and Endocrinology, VINCA Institute of Nuclear Sciences, Beograd, Serbia and Montenegro.
authors.forename: M
authors.initials: M
authors.lastname: Adzić
authors.forename: A
authors.initials: A
authors.lastname: Nićiforović
authors.forename: Z
authors.initials: Z
authors.lastname: Nesković-Konstantinović
authors.forename: M B
authors.initials: MB
authors.lastname: Radojcić