The dietary phytochemical myricetin induces ROS-dependent breast cancer cell death

Abstract

Myricetin is a dietary phytochemical found in a variety of fruits and vegetables. Myricetin has several anti-cancer effects on human cancer cells, including bladder, pancreatic, and colorectal cancers; however, the effect of myricetin on breast cancer cells remains unclear. The goals of this study were to first determine if myricetin caused breast cancer cell death and then to establish the mechanisms underlying myricetin-induced breast cancer cell death. Myricetin decreased the viability of human mammary carcinoma cells, including triple-negative breast cancer cells. Myricetin induced cell death of triple-negative breast cancer cells in a reactive oxygen species (ROS)-dependent manner. Myricetin-induced ROS caused decreased mitochondrial membrane stability, increased DNA damage, and increased p38 MAPK phosphorylation. The myricetin-induced ROS was likely formed by myricetin autoxidation in cell culture medium to form H2O2. The potent anti-breast cancer effect of myricetin argues in favour of further investigation of myricetin as a potential breast cancer therapeutic.