MTOR and breast carcinoma: The formation of breast cancer CSCs was accompanied with transcriptional repression of three mTOR suppressors (PKAA1, DDIT4/REDD1, and deptor) as well as upregulation of phosphorylated S6K protein levels, again signifying the activation of mTOR pathway in the acquisition of CSC-like cellular states (Corominas-Faja et al., 2013).