The Effect of Coenzyme Q10 Supplementation on Vascular Endothelial Growth Factor and Serum Levels of Interleukin 6 and 8 in Women with Breast Cancer: A Double-Blind, Placebo-Controlled, Randomized Clinical Trial

BACKGROUND: To better evaluate the efficacy of CoQ10 on the inflammatory markers in breast cancer patients, we conducted a clinical study of patients with breast cancer undergoing tamoxifen therapy. CoQ10 serves as an antioxidant and inhibits oxidation caused by reactive oxygen species. The aim of the current study was to assess the effect of coenzyme Q10 supplementation on serum levels of interleukin 6, 8, and vascular endothelial growth factor (VEGF) in patients with breast cancer undergoing tamoxifen therapy by a double-blind, placebo-controlled, randomized clinical trial. METHODS: In the study, 30 breast cancer patients and 29 healthy subjects were randomized into four groups. Two groups of intervention received 100 mg CoQ10, and two control groups took placebo once a day for 2 months. Blood draws were obtained at baseline and at the end of the study. Serum levels of IL-6, IL-8 and VEGF were analyzed using ELISA kits. RESULTS: The data of the 59 participants were analyzed. Supplementation with CoQ10 demonstrated a significant decrease in IL-8 and IL-6 serum levels compared to placebo (P< 0.05). Although the downward trend was evident, CoQ10 supplementation did not reveal any significant effect on serum VEGF concentration. The group of patients who received supplements showed the most reduction in serum levels of cytokines among other groups. CONCLUSION: CoQ10 supplementation could be effective in ameliorating inflammatory cytokine levels, thereby reducing the consequences of inflammation caused by breast cancer. To generalize the results, larger and longer intervention studies with higher safe doses are needed and should take account of possible costs and harms as well as benefits (registration number: IRCT2015042021874N1).