Myricetin induces apoptosis mediated by oxidative stress in 4T1 and E0771 mammary cancer cells

Background Myricetin is a polyphenolic compound that is cytostatic and/or cytotoxic for several cancer cell types; however, little is known about its effect on mammary carcinoma cells. Objective The objective of this study is to determine whether myricetin affects the growth of mammarycarcinoma cells. Results Myricetin inhibited the growth of 4T1 and E0771 mouse mammary carcinoma cells to a greater extent than either resveratrol or epigallocatechin-3-gallate, which are also present in red wine and green tea, respectively, and also have anti-cancer activities. Reduced growth of myricetin-treated 4T1 and E0771 cells was the result of apoptosis that was associated with disruption of the outer membrane of mitochondria. Myricetin-induced apoptosis of 4T1 and E0771 cells was prevented by the antioxidant N-acetyl cysteine, indicating that cytotoxicity was the result of oxidative stress caused by the accumulation of reactive oxygen species. Conclusion We conclude that the pro-oxidant action of myricetin and ensuing apoptosis of mammary carcinoma cells indicate that myricetin may be useful in breast cancer treatment.