Restoring wild-type ARID1A or inhibiting EZH2, the catalytic subunit of polycomb repressive complex 2, inhibits Phosphoinositide 3-kinase/AKT signaling through up-regulation of PIK3IP1. Profiling of ARID1A-deficient tumors in a mouse ovarian cancer model showed enrichment for genes associated with mesenchymal-epithelial transition (21). Here, ARID1A is linked to ovarian cancer.