3D tumor spheroid culture alters basal EGFR and cMET phosphorylation and response to ligand stimulation.

Day four 2D monolayer cultures and 3D spheroid from eight lung tumor cell lines were stimulated with or without 100/ml of EGF or HGF for 15 minutes. Phosphorylation for EGFR and cMET was determined by MSD assay. N is equal to 4 replicates per condition. T-test comparing basal phosphorylation in 2D verses 3D cultures. (* indicates p<0.05 and ** indicates p<0.005).