Abstract #2313: Induced oxidative stress and cell death in the A549 lung adenocarcinoma cell line by ionizing radiation is enhanced by supplementation with docosahexaenoic acid

Both ionizing radiation and docosahexaenoic acid (DHA), an n-3 polyunsaturated fatty acid (PUFA), have been shown to inhibit tumor cell growth at least in part by increasing oxidative stress. In the current study, the effects of ionizing radiation, DHA, or a combination of the two on lipid peroxidation (TBARS), cell proliferation, apoptosis (Annexin V-FITC) and anchorage-independent cell growth (soft agar) in A549 lung adenocarcinoma cells were examined. While one previous report using a breast cancer xenograft did not show a significant enhancement to radiation therapy with DHA supplementation (Hardman et al ., 2005), most other studies have shown DHA is capable of improving tumor cell response to ionizing radiation. Significant decreases in cell proliferation and colony formation in soft agar were noted for ionizing radiation or DHA treatments, while a combination of the two showed significant reductions over either treatment alone. Conversely, lipid peroxidation and early and late stage apoptosis showed significant increases with ionizing radiation and DHA treatments, while cells receiving both treatments demonstrated further significant increases. These findings confirm the potential of DHA supplementation to enhance cancer treatments using ionizing radiation by increasing oxidative stress and enhancing tumor cell death. Citation Information: In: Proc Am Assoc Cancer Res; 2009 Apr 18-22; Denver, CO. Philadelphia (PA): AACR; 2009. Abstract nr 2313.