These divergent subtypes highlight the role of MYCN as a master regulator of chromatin dynamics, enabling NEPC cells to adopt diverse NE identities.145 In SCLC, NE transformation mechanisms are similarly complex, with tumors often displaying varying expression levels of lineage-defining markers such as ASCL1, NEUROD1, and POU2F3.146 A distinct subtype with YAP1 expression has been identified, demonstrating low levels of canonical NE markers. This evidence concerns the gene ASCL1 and small cell lung carcinoma.