POU2F3 and small cell lung carcinoma: Figure 3 also shows that the NEUROD1-positive regions in SCLC samples correspond to YAP1- and POU2F3-positive regions, as YAP1-positive regions correspond to POU2F3-positive regions. These results suggest that the four key molecules are coordinately and simultaneously expressed in SCLC cells. The co-expression of the four key molecules in SCLC samples suggests an interaction among these molecules. A recent study reported that SCLC-expressing ASCL1 shifted to the expression of NEUROD1 and YAP1 following the activation of MYC [29].