We have previously demonstrated the efficacy of a therapeutic directed against the juxtamembrane domain region 643–663 of HER1 (EGFR Juxtamembrane Peptide 1—EJ1), capable of inhibiting HER1-3 activation, reducing calcium/calmodulin-associated proliferation, promoting cell death through necrosis and apoptosis, and reducing tumor growth and metastasis in MMTV-pyMT mice with mammary tumors [19]. The gene discussed is EGFR; the disease is breast cancer.