Resistance to EGFR-Targeted Therapy: A Family Affair

The EGFR-directed antibody cetuximab has proven, albeit modest, clinical benefit as monotherapy in head and neck and colorectal cancers. In a recent study, Yonesaka et al. uncovered a new mechanism of cetuximab resistance mediated by increased ERBB2 signaling via amplification of ERBB2 or increased levels of the ERBB3/ERBB4 ligand heregulin.