Abstract
The effects of ligand activation of PPARbeta/delta were examined in the mouse mammary tumor cell line (C20). Expression of PPARbeta/delta was markedly lower in C20 cells as compared to the human non-tumorigenic mammary gland derived cell line (MCF10A) and mouse keratinocytes. Ligand activation of PPARbeta/delta in C20 cells caused upregulation of the PPARbeta/delta target gene angiopoietin-like 4 (Angptl4). Inhibition of C20 cell proliferation and clonogenicity was observed following treatment with GW0742 or GW501516, two highly specific PPARbeta/delta ligands. In addition, an increase in apoptosis was observed in C20 cells cultured with 10microM GW501516 that preceded the observed inhibition of cell proliferation. Results from this study show that proliferation of the C20 mouse mammary gland cancer cell line is inhibited by ligand activation of PPARbeta/delta due in part to increased apoptosis.