Figure 4.

The anti-HER3 D1 Abs 9F7-F11 (■) and 16D3-C1 (△) and the anti-HER3 D3 Ab H4B-121 (○) inhibit tumor growth (left panel) and increase survival time (right panel) compared to vehicle (NaCl; ◆) in mice xenografted with HER2 non-amplified pancreatic carcinoma BxPC3 cells (wild-type PIK3CA and p53) (A), NRG-addicted, HER2 non-amplified epidermoid carcinoma A431 cells (wild-type PIK3CA and mutant p53) (C), or triple-negative, EGFR-amplified breast carcinoma MDA-MB-468 cells (wild-type PIK3CA and mutant p53) (D). BxPC3 tumor lysates from vehicle- or Ab-treated mice were prepared 24 days after the beginning of the treatment (tumor sizes are indicated) and HER3 phosphorylation at Tyr¹²⁸⁹ was assessed by Western blot analysis (B). Tumor growth data are presented as the mean tumor volume ± SEM for each group of nude mice (n = 8 per condition, but for the MDA-MB-468 xenograft model, n = 7). Kaplan-Meier survival curves were calculated when tumors reached a volume of 2000 mm³ and mice were sacrificed.