122. Psychological risk factors are related to higher levels of antioxidant enzyme activity in ovarian cancer patients

Abstract

Reactive oxygen species (ROS) are produced during mammalian metabolism. ROS are quenched by the action of antioxidant enzymes such as Manganese Superoxide Dismutase (MnSOD) and Glutathione Peroxidase (GPx). In healthy tissue, when ROS accumulate and cause damage to DNA, proteins, and lipid membranes, apoptosis can be triggered. In cancer tissue, cellular metabolism is upregulated, and it has been hypothesized that the activity of antioxidant enzymes may be upregulated, ultimately acting to protect cancer cells from reaching a ROS-derived apoptosis signal threshold. Relationships between psychosocial factors and antioxidant enzyme activity in human tumors have not previously been examined. Here, we examined associations of MnSOD and GPx in primary ovarian tumor tissues with indicators of psychological distress (CES-D) prior to surgery. Frozen tumor tissue was analyzed for MnSOD and GPx. Significantly higher levels of MnSOD were detected in higher grade tumors ( p < 0.001). In hierarchical linear regressions controlling for stage and age, higher levels of the CES-D depressed mood subscale ( n = 75, p = 0.01) were associated with significantly higher MnSOD levels in high grade tumors. In contrast, GPx was associated with lower levels of vegetative depression ( n = 74, p = 0.049) and marginally associated with greater positive mood ( N = 73, p = 0.056) but not with depressed mood ( p = 0.44). No relationships were seen between MnSOD and positive mood or vegetative depression (all p values >0.60). Ongoing research is examining the clinical relevance of these findings.