PDX1 and pancreatic insulinoma: For example, PPARαδPdx-1 displays an protecting effect against GSIS insult in rat isolated pancreatic islets and rat insulinoma cells.31, 32 However, PPARγ improves Pdx-1 transcription accompanied by reducing insulinoma cell numbers without affecting Pdx-1 protein expression and GSIS function.31, 32 It implies that diverse regulating links may exist between different PPAR subtypes and Pdx-1.