In a preclinical study, Priceman et al. 2018 demonstrated that experimental breast cancer brain metastasis responded similarly in terms of tumor-infiltration and extended preclinical survival after i.c.v. or intratumoral locoregional administration of 0.5 × 106 HER2-directed BBζ CAR-T in BBM1 tumor-bearing mice [47]. The gene discussed is ERBB2; the disease is breast cancer.