Fig. 2
Cellular viability upon combined targeting of HER-2/HER-3. Cellular viability of LS513, LS1034, and SW837 cells was assessed 24 h (black curve), 48 h (red curve), and 72 h (blue curve) after treatment with various combinations of trastuzumab and pertuzumab. The inhibitory effect on downstream signaling was evaluated by Western blot analysis. All experiments were performed in triplicate, independently repeated three times. (a + b) Two different doses of pertuzumab were combined with increasing concentrations of trastuzumab. (c + d) Two different doses of trastuzumab were combined with increasing concentrations of pertuzumab. The respective P-values and the (estimated) EC50 for all drugs and time points are listed in Additional file 5: Table S1