Although moststudies indicate that PPARδ activation results in stimulation of cellgrowth, mostly in human and mouse colon cancer cells [7, 36], there have beenprevious findings showing that PPARδ agonists, including GW501516, can hinder orhave no effect on cell growth in certain human breast cancer cells andmelanomas [37, 38]. The gene discussed is PPARD; the disease is breast carcinoma.