As a mammalian target of rapamycin (mTOR) inhibitor, rapamycin and its derivatives CCI-779, RAD001 and AP23573 can effectively inhibit the growth of a broad range of tumours, such as malignant glioma, breast cancer, renal cell carcinoma, non-small-cell lung cancer, mesothelioma, soft-tissue sarcoma, and cervical and uterine cancers40. Here, MTOR is linked to breast cancer.