PPARγ and Apoptosis in Cancer

Peroxisome proliferator-activated receptors (PPARs) are ligand binding transcription factors which function in many physiological roles including lipid metabolism, cell growth, differentiation, and apoptosis. PPARs and their ligands have been shown to play a role in cancer. In particular, PPAR gamma ligands including endogenous prostaglandins and the synthetic thiazolidinediones (TZDs) can induce apoptosis of cancer cells with antitumor activity. Thus, PPAR gamma ligands have a potential in both chemoprevention and therapy of several types of cancer either as single agents or in combination with other antitumor agents. Accordingly, the involvement of PPAR gamma and its ligands in regulation of apoptosis of cancer cells have been extensively studied. Depending on cell types or ligands, induction of apoptosis in cancer cells by PPAR gamma ligands can be either PPAR gamma-dependent or -independent. Through increasing our understanding of the mechanisms of PPAR gamma ligand-induced apoptosis, we can develop better strategies which may include combining other antitumor agents for PPAR gamma-targeted cancer chemoprevention and therapy. This review will highlight recent research advances on PPAR gamma and apoptosis in cancer. Copyright (C) 2008 H. A. Elrod and S.-Y. Sun.