The co-expression of NEUROD1 with ASCL1 might drive malignant cells to a ‘variant’ subtype of SCLC, showing an enrichment of signatures involved in the hallmarks of angiogenesis and EMT (Supplementary Fig. S6b), which would promote tumor cell survival and metastasis.39 This ‘hybrid’ state might indicate biological plasticity between subtypes that is shaped by the microenvironment and tumor progression. Here, ASCL1 is linked to small cell lung carcinoma.