Macrophage co-culture stimulated neoplastic proliferation can be blocked by combined kinase inhibition. A-B: Neoplastic (A) LM2 or (B) JF32 cells were cultured alone (-MØ, white bars) or with primary BAL macrophages (+MØ, black bars). Co-culture media was supplemented with 0.05% DMSO (vehicle), 5 μM U0126 (U0) and/or 10 μM LY294002 (LY). Proliferation was determined by MTS and mean + SD plotted as fold-change from vehicle control. Data was pooled from 3 independent experiments. * P < 0.05 and ** P < 0.001 versus-MØ control for each treatment by 2-way ANOVA.