ASCL1 and small cell lung carcinoma: Intratumoral heterogeneity coerces more complexity by establishing different molecular subtypes; for example, in small cell lung cancers (SCLC), these signatures are driven by transcription factor, which include achaete-scute family bHLH transcription factor 1 (ASCL1), neurogenic differentiation factor 1 (NeuroD1), POU domain class 2 transcription factor 3 (POU2F3), and yes-associated protein 1 (YAP1) (Borges et al., 1997; Huang et al., 2018; Rudin et al., 2019; Duplaquet et al., 2024; He et al., 2024).