Neurodevelopmental and COSMIC-based transcript expression in SI NET samples. A. Enteroendocrine-related transcription factors in each of the data sets identified expression of 3 and 12 murine ortholog TFs, respectively. Commonly expressed TFs, involved in the regulation of neurodevelopment, included INSM1, NKX2-2 and ST18. B. QPCR analysis of transcripts predicted by COSMIC analysis to be decreased in small intestinal NETs. Both CEBPA and SDHD expressed levels ~50% of normal mucosa consistent with a decreased expression and potentially a loss of function as has been noted in hematological cancers  and paragangliomas . C. QPCR analysis of neurodevelopmental transcripts in the independent set confirmed elevated expression of INSM1, and NEUROD1 and elevated expression of BEX1 and NKX2-2 validating the transcriptome-based analyses. Mean ± SEM, *p < 0.05 vs. normal mucosa. Tumors n = 13, normal mucosa n = 8.