Simvastatin-induced down-regulation of Akt/PKB, p42/p44 Erk, and mTORC1 and up-regulation of cleaved caspase-3. TSC2-null cells were treated with 0, 0.5, 1.0, 5.0, and 10 μM of atorvastatin or simvastatin followed by immunoblot analyses with phospho-Ser473-Akt/PKB and Akt/PKB (A), phospho-S6 and ribosomal protein S6 (B), phospho-p42/p44 Erk and total p42/p44 Erk (C), and with cleaved caspase-3 (D) antibodies.