T cell-engaging bsAbs (TCEs) are specifically engineered to simultaneously bind to a predefined tumor-associated antigen (TAA) on the surface of cancer cells and to one of the extracellular CD3 subunits (usually CD3ε) of the T cell receptor (TCR) expressed on the surface of T cells, leading to the release of preformed cytotoxic proteins, such as perforin and granzymes, as well as cytokines [4,5]. This evidence concerns the gene CD3E and cancer.