DPF1 and neuroendocrine carcinoma: Transcription factor enrichment analysis of the DEGs showed that in 7 of the top 10 potential transcription factors of the DEGs: SCRT1, DPF1, ZnF488, PIN1, CUX2 previously promoted neural differentiation and neuroendocrine cancer progression, while EMX1 and MYRF were reported to promote the development of nervous system [27,28,29,30,31,32,33], implying that cluster 6 might be regulated by neural related genes (Figure 3I).