Genetic disruption or prolonged pharmacological inhibition of sonic hedgehog, a ligand that stimulates CAFs (Tian et al., 2009; Lee et al., 2014; Rhim et al., 2014), or depletion of αSMA-expressing cells (Özdemir et al., 2014), resulted in undifferentiated PDA tumors and decreased survival in mice. Here, ACTA1 is linked to Patent ductus arteriosus.