In addition, Expi293F cells can also be designed to express CD3 and HER2 antibodies to secrete and express multivalent antibodies to redirect exosomes, dual target T cell CD3 and breast cancer-related HER2 receptors, and activate CTL cells to target HER2-positive breast cancer cells (Shi et al., 2020). This evidence concerns the gene ERBB2 and breast cancer.