(a)

(b)

Figure 7: Inhibition of HER2 tyrosine kinase activity (2.5 μM AG879) in addition to that of EGFR results in greater inhibition of ERK1/2 phosphorylation as compared to EGFR inhibition alone (10 μM) (a) in HT-29 cells. (b) is a loading control, 25 μM PD98058. Figure is representative of three separate experiments.