MTOR and ovarian cancer: Moreover, re-expression of the tumor suppressor gene aplasia Ras homolog member I (ARHI; also known as DIRAS3), which is maternally imprinted, and is frequently downregulated in ovarian cancer, promoted autophagy through inhibition of phosphatidylinositol 3-kinase (PI3K) signaling and mammalian target of rapamycin (mTOR), and upregulation of ATG4 cysteine protease.