Classical PDA is enriched for expression of epithelial differentiation genes, whereas basal-like PDA is characterized by laminin and basal keratin gene expression, stem cell and epithelial-to-mesenchymal transition (EMT) markers, analogous to the basal subtypes previously defined in bladder and breast cancers (Perou et al., 2000; Parker et al., 2009; Curtis et al., 2012; Cancer Genome Atlas Research Network, 2014; Damrauer et al., 2014). This evidence concerns the gene LAMB2 and Patent ductus arteriosus.