The three GEP-NEC cell lines (NEC-DUE1, NEC-DUE2 and A99) have been evaluated for their expression of neuroendocrine markers and for their high Ki67 index using xenograft models (Yachida et al., 2011; Krieg et al., 2014). The gene discussed is MKI67; the disease is neuroendocrine carcinoma.