Early reports identified that Smad4‐knockdown human pancreatic cancer cells or mouse keratinocytes with Smad4 gene knockout exhibited increased spontaneous DNA damage and reduced DNA repair.[15, 31] Consistent with the genetic knockout mouse model, the protein levels of classical DNA damage markers, γ‐H2AX and RAD51, were markedly increased in Smad4KO cells (Figure S5B,C, Supporting Information). Here, RAD51 is linked to familial pancreatic carcinoma.