Non-NE SCLC has been subdivided into SCLC-Y and SCLC-P based on elevated expression of the transcription factors YAP1, involved in HIPPO signaling, and POU2F3, which signifies tuft cell rather than pulmonary NE cell origin, respectively (Rudin et al., 2019 and references therein). Here, YAP1 is linked to small cell lung carcinoma.