Figure 7

cAMP effects are independent of ERK. Wild type H1944 cells were transfected with oligonucleotides directed against ERK1 or against control, NTC sequences for 48 h as described in Figure 5. The transfected cells were replated and treated with media containing vehicle, 200 µM phe-cAMP or 200 µM me-cAMP and assayed for growth over 5 days. ERK1 knockdown had no effect on the growth inhibitory effects of the cAMP analogs. Inhibition for phe-cAMP amounted to 50–60% compared to vehicle and roughly 40% for me-cAMP. ^‡P < 0.001. The graph on the right shows that the ERK1 siRNA reduced ERK1 expression by about 50%. **P < 0.01.