PPARG and prostate cancer: Additionally, an in vitro experiment suggested that peroxisome proliferator-activated receptor-γ (PPAR-γ) could be stimulated by repeated exposure to MEHP and that PPAR-γ plays a vital role in prostate cancer development and progression [28], while another animal study indicated that the risk of liver tumors was higher in PPARα-null mice exposed to DEHP than in wild-type mice, which suggested that DEHP could activate the PPARα pathway [32].