Figure 3. Molecular inhibition of ERBB receptors recapitulates the effects of lapatinib. (A) GBM12 cells were transfected with scrambled control siRNA (siSCR, 20 nM) or with siRNA molecules to knock down expression of ERBB1-3. Twenty four h after transfection cells were treated with vehicle (DMSO) or with OSU-03012 (1 μM). Cells were isolated 48h later and viability determined by trypan blue exclusion assay (n = 3 ± SEM). (B) DAOY cells were transfected with scrambled control siRNA (siSCR, 20 nM) or with siRNA molecules to knock down expression of ERBB1–4. Twenty four h after transfection cells were treated with vehicle (DMSO) or with OSU-03012 (1 μM). Cells were isolated 48h later and viability determined by trypan blue exclusion assay (n = 3 ± SEM).