Our data demonstrated that interference with MIR503HG activated the MAPK and PI3K/AKT signaling pathways, while TMEFF1 silence rescued the effect of MIR503HG siRNA on the two pathways, suggesting that MIR503HG might regulate the MAPK and PI3K/AKT pathways by affecting the expression of TMEFF1, thereby participating in the progression of ovarian cancer. The gene discussed is MIR503HG; the disease is ovarian cancer.