In a recent study, Cheng et al. generated a novel synthetic multivalent antibodies retargeted exosome (SMART-Exo) through cell engineering, which expressed monoclonal antibodies specific for T cell CD3 and cancer cell-associated epidermal growth factor receptor (EGFR) and was shown to induce cross-linking of T cells and EGFR-expressing breast cancer cells 55. This evidence concerns the gene EGFR and breast cancer.