The Hep293TT cell line  was kindly provided to us by Dr. Gail Tomlinson from the University of Texas Southwestern Medical Center. Hep293TT cells were cultured in Roswell Park Memorial Institute (RPMI) 1640 medium, 25mM Hepes, 10% fetal bovine serum (FBS) and 1% penicillin/ streptomycin (Gibco). HepG2 and SNU449 cells were purchased from ATCC and they were cultured in Dulbecco’s modified Eagle medium (DMEM) supplemented with 10% FBS and 1% penicillin/ streptomycin. To block mTORC1 signaling, MLN0128 (LC Laboratories), a second generation of mTOR kinase inhibitor was diluted to gradient concentration and added to the cells. Dimethyl sulfoxide (DMSO) was diluted and used as control. After 48 hours treatment, cells were stained with crystal violet or collected for protein analysis. Cell proliferation and apoptosis were assessed using the BrdU Cell Proliferation Assay Kit (Cell Signaling Technology Inc) and the Cell Death Detection Elisa Plus Kit (Roche Molecular Biochemicals, Indianapolis, IN), respectively, following the manufacturers’ instructions.