To evaluate the biological functions of m6A regulators in breast cancer, a total of 15 m6A regulators including six writer complexes (METTL3, METTL14, METTL16, WTAP, VIRMA, RBM15), two erasers (FTO, ALKBH5), and seven readers (YTHDC1/2, YTHDF1/2/3, HNRNPA2B1, EIF3A) were investigated based on available TCGA dataset. The gene discussed is METTL3; the disease is breast cancer.