STEAP1 and Familial prostate cancer: In addition, six transmembrane epithelial antigen of the prostate 1 (STEAP1) is highly expressed in in metastatic state and demonstrated as a promising therapeutic target in prostate cancer, STEAP1-directed chimeric antigen receptor (CAR) T cells demonstrate effective antitumor activity, even in low antigen density, and exhibit safety in preclinical models.