IRS2 and polycystic ovary syndrome: It has been suggested that PCOS patients have downregulated expression of miR-92a and miR-92b in theca cells, which regulate 17-hydroxylase/C17–20 lyase cytochrome P50 (CYP17), GATA-binding factor 6 (GATA6), and insulin receptor substrate proteins 2 (IRS-2) expression [45].