Importantly, SCLC-A can be further divided into two subtypes: SCLC-Aα, which expresses NKX2-1 and SOX1 and maintains a strong NE phenotype; and SCLC-Aσ, which lacks these markers and may represent a transition state toward NE-low tumors [21]. The gene discussed is SOX1; the disease is small cell lung carcinoma.