POU3F3 and neoplasm: The expression of POU3F3 is highly and widely observed in the central nervous system, where it plays a crucial role in neuronal development through its collaboration with SOX4.[16] Remarkably, the differentiation of lung cancer into a proneural/neuroendocrine phenotype has been observed in approximately one‐third of cases and likely exert a significant impact on tumor progression of lung cancer.