MTOR and breast cancer: These mainly include the PI3K/Akt/mTOR and MAPK/ERK signal pathways, downregulating ER expression via phosphorylation of the PI3K/Akt/mTOR signal pathway and phosphorylating ER Ser118 via activation of the MAPK/ERK pathway, which correlates with the poor clinical outcomes of breast cancers[2,22,24,25].