ERBB4 and neoplasm: When 3 of these tumor cell lines (SAS, HPC9Y and Calu-1) that expressed low levels of HER-3 were treated with an irreversible HER family broad inhibitor (dacomitinib, which inhibits EGFR, HER-2 and HER-4 but not HER-3), the expression of HER-3 was substantially increased (Fig. 1B,C).