In other studies, delphinidin inhibits HER‐2 and ERK1/2 signaling and induces apoptosis in breast cancer cell lines.32 Furthermore, delphinidin suppresses proliferation and migration of human ovarian clear cell carcinoma cells.43 In the present study, we performed a MTT assay to compare the cytotoxic effects of delphinidin treatment on OS cell lines (HOS, U2OS, and MG‐63 cells). The gene discussed is ERBB2; the disease is breast cancer.