Fig 1. Lumretuzumab and pertuzumab both potently inhibit HER2/HER3 signaling.
MC7-7 cells (3 × 105 per six-well plate) were stimulated with or without HRG (5 ng/mL for 10 minutes) in vitro and treated with pertuzumab, trastuzumab, or lumretuzumab each at 10 μmol/L or vehicle control (PBS) for 1 hour, after which cell lysates were examined by Western blotting. Downregulation of pHER3, pMAPK, and pSHC was greater with pertuzumab than trastuzumab (A). Lumretuzumab monotherapy effectively inhibited HER2/HER3 signaling (B). All experiments were carried out in triplicate.