As a result, complete growth inhibition was observed after administering a TRAB against HER2 and human CD3 in a model engrafted with syngeneic tumor cells that express both human HER2 and human GPC3 (Fig. 10A), and several in vitro experiments demonstrated that the growth inhibition effect was via TDCC activity (Figs 8 and 9). The gene discussed is ERBB2; the disease is neoplasm.