Figure 3.

Effects of genistein and PD98059 on hGM-CSF-dependent signaling events, proliferation, and viability. (A) Activation of ERK2 and JNK1 through hGM-CSF wild-type receptor in BA/F3 cells in the presence of either genistein or PD98059 or both was analyzed by Western blotting (ERK2) or kinase assay (JNK1), as described in MATERIALS AND METHODS. The Western blot pattern of JNK1 is shown to indicate the amount of immunoprecipitated JNK1. (B) Effects of PD98059 (●), genistein (○), wortmannin (▴), or DMSO as a control (▪) on [³H]thymidine incorporation induced by hGM-CSF. BA/F-wild cells (1.2 × 10⁴ per well) were seeded in a 96-well plate in the presence of various doses of the indicated inhibitors and cultured for 24 h and then for an additional 4 h in the presence of [³H]thymidine. (C) Long-term proliferation and cell viability of BA/F-wild and -Fall cells in the presence of genistein (10 μg/ml), PD98059 (100 μM), or wortmannin. Viable cells were counted by trypan blue exclusion assay, and every 2 d cells were split and transferred to fresh media containing drugs.