CYP17A1 and polycystic ovary syndrome: As shown in our previous studies, the SET protein plays a positive role in regulating human ovarian androgen biosynthesis by increasing the transcription of the steroidogenic enzymes CYP17a1 and HSD3b1, and the SET‐initiated and PP2A‐mediated pathways lead to the increased lyase activity of CYP17a1 and T biosynthesis, which may contribute to hyperandrogenism in PCOS (Gao et al., 2013; Xu et al., 2013a,b).