MTOR and cancer: In the current study, we found that both CaP-RR and CaP cells are more sensitive to four inhibitors than the normal prostate RWPE-1 cells, and that CaP cells are more sensitive than CaP-RR cells (Supplementary Table S1), suggesting that PI3K/mTOR inhibitors more selectively target cancer cells but not normal cells and that CaP-RR cells are more resistant to these inhibitors.