In the autochthonous PRP130 animals, p-CREB was highly expressed in SCLC compared to cells in the normal adjacent airway (Extended Data Fig. 10f); p-CREB was also expressed in the PDX models (Extended Data Fig. 10g) and showed a trend towards higher expression in advanced hSCLC tumours (Extended Data Fig. 10h). Here, CREB1 is linked to neoplasm.