SYP and neuroendocrine neoplasm: Furthermore, genes encoding canonical markers of neuroendocrine tumors—including CHGA (chromogranin A), SYP (synaptophysin), NCAM1 (CD56), and ENO2 (neuron-specific enolase)—were all differentially higher in s3 tumors (Figures 4A and S6 and Tables S3 and S4).