METTL14 and breast cancer: Induced mature miR‐126 was finally identified as a tumour suppressor.50 It was also discovered that METTL14 presented a markedly decreased tendency in breast cancer50 and miR‐126 was also recognized as a metastasis suppressor of breast cancer,51 which indicated that METTL14 possibly regulated breast cancer by targeting miR‐126 in a m6A‐dependent manner.