Recently, it has been demonstrated that these subpopulations can coexist within the same tumor as a result of lineage plasticity, with the ASCL1 subtype evolving into the NEUROD1 subtype and the latter into the YAP1 subtype [17,36], implying that these phenotypes are different phases within the same evolutionary process rather than distinct subtypes. The gene discussed is ASCL1; the disease is neoplasm.