AKT1 and breast carcinoma: Moreover, ERα physically interacts with PPARγ in a multiprotein complex involving p85, the regulatory subunit of the phosphatidylinositol 3-kinase (PI3K) survival pathway, even though ligand-activated PPARγ, exerting an opposite effect on the PI3K/AKT transduction pathway compared to ERα, induces breast cancer cell growth inhibition.