F11R and neoplasm: Indeed, an inhibitory monoclonal antibody directed against JAM-A has shown promise in reducing tumor progression in murine models of breast and skin cancer [54], a JAM-A peptide antagonist has reduced transendothelial migration of breast cancer cells [55], and an antibiotic that degrades JAM-A has displayed cytotoxicity against primary breast cells and inhibited growth in a chick embryo xenograft model of breast cancer [15].