PPARG and breast carcinoma: In the present study with the human breast cancer cell line MCF-7, we have compared the effects and interactions of both native and synthetic retinoids (ATRA and 4HPR) and PPARγ agonists (15-deoxy-delta 12,14-prostaglandin J2, 15d-PGJ2 and TGZ) on cell growth, survival and ceramide production.