PDX1 and keratoconus: Since 2003, the KrasG12D;Pdx1-Cre (KC) and KrasG12D;Trp53R172H;Pdx1-Cre (KPC) mouse models (Hingorani et al., 2003; Hingorani et al., 2005; Rachagani et al., 2012 b) have been used extensively to study the pathogenesis of pancreatic cancer (PC).