A vaccine composed of a phosphorylated peptide from the tumor-associated antigen breast cancer anti-estrogen resistance-3 (BCAR3) and a tetanus-derived peptide, with potential immunomodulating and antineoplastic activities. Upon administration of pBCAR3 phosphopeptide-tetanus peptide vaccine, the pBCAR3 phosphopeptide may stimulate the immune system to mount a cytotoxic T-lymphocyte (CTL) response against phosphopeptide-containing tumor cells. The tetanus peptide serves as an immunoadjuvant and induces a helper T-cell response, which may help stimulate an immune response against the pBCAR3-expressing melanoma tumor cells. BCAR3 is upregulated in a variety of cancer cells.