CYP17A1 and polycystic ovary syndrome: Based on previous studies and our study, we suggest that cryptotanshinone could be used to reduce the androgen excess of PCOS and that the mechanism of reducing the androgen excess with cryptotanshinone in PCOS patients possibly functions through increasing the expression of P-ERK1/2 and promoting the expression of c-Fos that then reduces the expression of CYP17 and results in decreased androgen levels in PCOS granulosa cells.