Figure 5.

Effect of Erk1/2, Akt, and P38 MAPK inhibition on NRP-1 and VEGF induction by EGF in NCI-N87 cells. The cells were incubated in 5% serum-containing medium overnight and then were pretreated with 50 μM PD98059, 10 μM U0126, 200 nM wortmannin, or 25 μM SB203580 for 1 h in 1% FBS-containing medium. EGF (50 ng ml⁻¹) was then added for 24 h. Control cells were not treated with EGF (lane 1) and cells treated with EGF without addition of signalling inhibitors served as another internal control (lane 2). Total RNA was extracted, and Northern blot analysis was performed. Blockade of the Erk1/2, Akt or P38 pathways all led variable decreases in NRP-1 and VEGF mRNA expression.