Oxidative DNA damage and total antioxidant status in serum of patients with esophageal squamous cell carcinoma

Background/Aims: Oxidative stress is connected with activation of somatic mutations and rates of cell proliferation existing in cancer tissue. High level of reactive oxygen species is a mutagenic factor for DNA damage. Antioxidants are the components of the cellular defense mechanism against reactive oxygen molecules. The aim of our study was to analyze DNA peroxidation products' concentration and total antioxidant level in serum of the patients with esophageal squamous cell carcinoma before and after esophagectomy. We examined these parameters as markers of cancer development. Methodology: We tested 18 patients (2 woman and 16 men, mean age 59.4 years) with esophageal squamous cell cancer before and after esophagectomy and 12 healthy people as a control group. Concentrations of 8-OHdG and enzymatic antioxidants level were analyzed in serum. Data were statistically analyzed by Mann-Whitney test. Results: We observed statistically significant higher concentrations of 8-OHdG and significant lower levels of enzymatic antioxidants in the patients with cancer in comparison to the control group. After esophagectomy we observed normalization of these parameters. In four patients the level of total antioxidants was low and 8-OHdG concentration was high during the whole time of treatment. These patients had disease progression. Conclusions: Estimation of serum 8-OHdG concentration and total antioxidant status may be helpful for monitoring cancer therapy in patients with esophageal squamous cell cancer.