Next to the expression of synaptophysin in the isolated neuroendocrine cancer stem cells (Fig. 3E, 4C), we detected synaptophysin in neural crest-derived stem cells from the nasal cavity of a female donor[23,22] (Fig. 4A) and female adipose tissue-derived mesenchymal stem cells (Fig. 4B), suggesting a new role of synaptophysin as a stem cell marker. Here, SYP is linked to neuroendocrine carcinoma.