High expression of miR-660-5p in breast cancer cells indicates its role in promoting proliferation and metastasis while suppressing apoptosis through direct binding to the transcription factor CP2 (TFCP2) [13], downregulation of tet-eleven translocation 2 (TET2), and activation of the PI3K/AKT/mTOR signaling pathway [14]. This evidence concerns the gene TET2 and breast cancer.