ASCL1 and small cell lung carcinoma: Furthermore, the expression of DLL3 is closely related to neuroendocrine differentiation, and the expression of the transcription factor achaete-scute homolog 1 (ASCL1), which is an important oncogenic driver for SCLC [15], regulates growth and survival of the SCLC cells and is found in 75% of SCLC cells [16].