Table S1.
Antibodies used in this study
| Receptor | Phosphorylation site | Source |
| EGFR | Santa Cruz Biotechnology sc-03 | |
| pEGFR | Y1068 | Cell Signaling 2234 |
| Y1045 | Cell Signaling 2237 | |
| Y1173 | Cell Signaling 4407 | |
| HER3 | Cell Signaling XP D22C5 | |
| pHER3 | Y1289 | Cell Signaling 4791 |
| Y1197 | Cell Signaling 4561 | |
| Y1221/1222 | Cell Signaling 4784 | |
| HER2 | Santa Cruz Biotechnology sc-284 | |
| pHER2 | Y1221/1222 | Cell Signaling 2249 |
| AKT | Cell Signaling 2920 | |
| pAKT | S473 | Cell Signaling 4060 |
| ERK1/2 (MAPK) | p44/42 | Cell Signaling 4696 |
| pERK | T202/Y204 | Cell Signaling 4370 |