The Role of Peroxisome Proliferator-Activated Receptor-γ in Breast Cancer

Peroxisome Proliferator-Activated Receptor-gamma (PPAR gamma) is an extensively studied ligand-activated nuclear hormone receptor that functions as transcription factor and plays an important role in diverse biological processes, such as lipid metabolism and insulin sensitization. Recent studies have demonstrated that PPAR gamma is over-expressed in many tumor types, including breast cancer, suggesting a possible role in tumor development and/or progression and a putative prognostic value. Moreover, naturally-occurring and synthetic PPAR gamma agonists promote growth inhibition, apoptosis and differentiation of tumor cells. The present review summarizes the available information on PPAR gamma expression in breast tumors and the use of PPAR gamma ligands as anti-cancer agents for breast cancer treatment, both in vitro and in vivo. Considering the data so far, specific PPAR gamma agonists seem to exert beneficial effects against breast cancer and may therefore represent potential therapeutic agents.