Abiraterone acetate (hereafter referred to as abiraterone) is targeting the AR signaling axis by inhibiting cytochrome P450 17A1 (CYP17A1) – an enzyme involved in intracellular biosynthesis of androgens that enables prostate cancer cells to bypass androgen deprivation (Fig. 4B) (Montgomery et al. 2008, Attard et al. 2009, Helsen et al. 2014). The gene discussed is CYP17A1; the disease is prostate cancer.