The effect of dietary soyabean isoflavones on photodynamic therapy in K562 leukemia cells

The soyabean isoflavones genistein (GEN) and daidzein (DA) are popular presented in diet. Isoflavones have a variety of biological activities including antioxidant and anticancer properties. On account of its antioxidant activity, isoflavones might protect cancer cells from free radical damage in photodynamic (PDT) during which reactive oxygen species (ROS) production was stimulated leading to irreversible tumor cell injury. In this study, the influence of GEN and DA on K562 cells in 5-aminolevulinic acid (ALA)-based PDT was demonstrated. The results showed that GEN inhibited cell proliferation and enhance cell apoptosis, lipid peroxidation, and DNA damage in ALA-PDT on K562 cells. However, DA did not enhance cell apoptosis, lipid peroxidation, and DNA damage in ALA-PDT. In conclusion, the results suggested that soy consumption during PDT did not decrease the effectiveness of cancer therapy on malignant cells.