Our group reported that trastuzumab modified with nuclear translocation sequence (NLS) peptides and modified with diethylenetriaminepentaacetic acid (DTPA) complexed to the Auger electron-emitting 111In ([111In]In-DTPA-trastuzumab-NLS) was more effective than trastuzumab for treatment of human HER2-positive BC tumours in mice (Costantini et al. 2010) and killed HER2-positive BC cells in vitro that were resistant to trastuzumab (Costantini et al. 2008). The gene discussed is ERBB2; the disease is breast cancer.