Furthermore, we investigated the specific roles of the FGF15 and ERK pathways in PCOS in vitro and observed that FGF19 overexpression facilitated the viability of KGN cells while inhibiting their apoptosis; however, LY3214996 (an ERK inhibitor) reversed the action of FGF19 overexpression in KGN cells. The gene discussed is FGF19; the disease is polycystic ovary syndrome.