To determine the interplay between oncogenic KRas and nuclear GSK-3β in PDA development, we generated Lox-STOP-Lox (LSL) nuclear-targeted GSK-3β animals and crossed them with LSL-KRasG12D mice under the control of the Pdx1-cre transgene—referred to as KNGC. Here, GSK3B is linked to Patent ductus arteriosus.