MTOR and cancer: A final issue compromising the efficacy of mTOR inhibitors is that a wide range72–76 of clinically relevant mutations in mTOR can increase the catalytic activity of mTOR and thus both mTORC1 and mTORC2, thereby reducing the effectiveness of such compounds toward the first two generations of mTOR inhibitors and dual PI3K/mTOR inhibitors in cancer cells72–76.