STK11 and cancer: Because c-Myc is a downstream target of mTOR in many cancers, we evaluated c-Myc expression in the cells and found that c-Myc expression was increased in QGP-1/shPTEN and QGP-1/shLKB1 cells and was further enhanced in QGP-1/shPTEN/LKB1 cells as compared to QGP-1/shLuc cells as shown in Figure 3C.