MTOR and lung carcinoma: α7-nAChR antagonist and short interfering RNA against α7-nAChR as well as inhibitors of phosphatidylinositol 3-kinase (PI3K; wortmannin and LY294002) and mammalian target of rapamycin (mTOR; rapamycin) blocked the expression of PPARβ/δ protein demonstrating a novel mechanism by which nicotine could promote human lung carcinoma cell growth [69].