Skip to main content
. 2011 Oct 10;121(11):4311–4321. doi: 10.1172/JCI57909

Figure 2. The increase in p-AKT induced by KRAS knockdown is consistent with loss of feedback inhibition from TORC1.

Figure 2

(A–C) SW620 cells infected with tetracycline-inducible KRAS shRNA were treated with 10 ng/ml doxycycline or vehicle for 72 hours. In parallel, parental SW620 cells were treated with DMSO, 50 nM rapamycin (Rap), or 1 μM MEK inhibitor AZD6244 (AZD) for 24 hours. (A and B) Protein lysates were probed with the indicated antibodies or (C) were subjected to immunoprecipitation with the anti-p85 antibody, followed by Western blot analyses with the indicated antibodies. KD, knockdown. (D) SW620 cells were treated with the indicated single-agent drug or drug combinations for 24 hours, and lysates were probed with the indicated antibodies. AZD, AZD6244 (1 μM); Gef/AZD, gefitinib (1 μM) and AZD6244 (1 μM); NVP/AZD, NVP-AEW541 (1 μM) and AZD6244 (1 μM); PHA/AZD, PHA-665752 (1 μM) and AZD6244 (1 μM). Note that the SW620 cells have undetectable EGFR, and no p-EGFR was detected. (E) Diagram of the feedback pathway from KRAS knockdown to PI3K activation.