A and B: GBM1B cells were treated with +/− Erlotinib or Gefitinib (10 μM, 16 hours) in growth factor-depleted medium followed by EGF treatment for the indicated times. TAZ western blotting was performed using total protein lysates (A) or proteins from the nuclear and cytosol fractions (B).
C - E: GBM1B cells were treated with or without the inhibitors as marked for 16 hours in growth factor-depleted medium followed by 4-hour EGF stimulation (5,15-DPP: 100 μM; PD98059: 20 μM; Akti-1/2: 20 μM). Total protein lysates were subjected to western blotting for TAZ and other proteins.
F: ChIP-PCR using STAT3 antibody and control IgG showed the interaction between STAT3 and a putative STAT3-binding site on the TAZ promoter (−500bp to the TSS).
Protein fold expression normalized to β-Actin is shown below each lane. Data are represented as mean ± SEM (*: p < 0.01).