POU3F2 and small cell lung carcinoma: POU2F3 (POU class 2 homeobox 3; also known as SKN-1a/OCT-11) is the master regulator of cell identity in the neuroendocrinelow variant of small cell lung cancer (SCLC).421 Co-immunoprecipitation assay performed by Zhou et al.422 revealed that the transcriptional co-activator COLCA2 (POU2AF3) and C11orf53 (POU2AF2) physically interacts with transcription factor POU2F3 to regulate tuft cell-like SCLC cell growth.