Model of suppression of TGIF function by KrasG12D/MPK-mediated phosphorylation. In this model, acquisition of KrasG12D leads to constitutive activation of MAPK/ERK, which in turn phosphorylates TGIF1. Phosphorylation of TGIF1 disrupts its ability to inhibit Twist1 expression, thereby leading to suppression of CDH1 and p16INK4A expression and attendant PDAC formation and progression. 