FIGURE 5.

NDRG1 expression inhibits MAPKK kinases that are downstream of EGFR signaling. PANC-1 (A) and HT-29 (B) vector control (VC) or NDRG1-overexpressing (NDRG1) cells were incubated with control media (Ctrl) or media containing EGF (10 ng/ml; 10 min/37 °C) and levels of MEK1, MEK2, pMEK1/2, and NDRG were examined by Western blot. β-Actin was used as a loading control. Western blots are typical of three independent experiments, with densitometric analysis representing mean ± S.D. (three experiments). Relative to untreated vector control cells: *, p < 0.05; **, p < 0.01; ***, p < 0.001. Relative to EGF-treated vector control cells: #, p < 0.05; ##, p < 0.01. Relative to untreated NDRG1 overexpressing cells: †, p < 0.05; ††, p < 0.01.