POU2F3 and small cell lung carcinoma: Given that SCLC has been recently classified in four different transcriptional subtypes defined by ASCL1, NEUROD1, POU2F3 (SCLC-A, SCLC-N, and SCLC-P) or YAP1 (SCLC-Y; or characterized by low expression of ASCL1, NEUROD1, and POU2F3 and accompanied by an Inflammatory gene signature; SCLC-I; refs. 1, 29), we next evaluated the expression of TREX1 across these different SCLC molecular subtypes.