RBFOX2 and Patent ductus arteriosus: To determine whether the splicing-regulatory activity of RBFOX2 is responsible for its effect on metastatic PDA, we attempted to rescue the phenotype of X50 metastatic PDA cells and BxPC3 primary PDA cells that express RBFOX2 EIJ sgRNA, using RBFOX2 cDNA that is deleted for the RRM (RBFOX2ΔRRM).