Vaccination of HLA-A2+ and HER-2/neu+ cancer patients with the helper peptide HER-2(15369), which contains the HER-2(9369) CTL epitope, resulted in increased frequencies of HER-2(9369) precursors and generated CD8+ CTL responses against tumour cell lines naturally expressing or pulsed to express HER-2(9369) (Knutson et al, 2001). Here, ERBB2 is linked to cancer.