DUSP1 and hepatocellular carcinoma: Exposure of formosanin C (diosgenin saponin) to HCC HepG2 and Huh-7 cells suppressed cell proliferation/migration/invasion by induction of cell apoptosis, and by upregulation of DUSP1 and activation of autophagy through AMPK/ULK1/Beclin1 axis.